xref: /openbmc/linux/net/core/filter.c (revision 098c0a373cdd51d3a735da7394acd6e57fae45a0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Linux Socket Filter - Kernel level socket filtering
4  *
5  * Based on the design of the Berkeley Packet Filter. The new
6  * internal format has been designed by PLUMgrid:
7  *
8  *	Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
9  *
10  * Authors:
11  *
12  *	Jay Schulist <jschlst@samba.org>
13  *	Alexei Starovoitov <ast@plumgrid.com>
14  *	Daniel Borkmann <dborkman@redhat.com>
15  *
16  * Andi Kleen - Fix a few bad bugs and races.
17  * Kris Katterjohn - Added many additional checks in bpf_check_classic()
18  */
19 
20 #include <linux/atomic.h>
21 #include <linux/bpf_verifier.h>
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/mm.h>
25 #include <linux/fcntl.h>
26 #include <linux/socket.h>
27 #include <linux/sock_diag.h>
28 #include <linux/in.h>
29 #include <linux/inet.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_packet.h>
32 #include <linux/if_arp.h>
33 #include <linux/gfp.h>
34 #include <net/inet_common.h>
35 #include <net/ip.h>
36 #include <net/protocol.h>
37 #include <net/netlink.h>
38 #include <linux/skbuff.h>
39 #include <linux/skmsg.h>
40 #include <net/sock.h>
41 #include <net/flow_dissector.h>
42 #include <linux/errno.h>
43 #include <linux/timer.h>
44 #include <linux/uaccess.h>
45 #include <asm/unaligned.h>
46 #include <linux/filter.h>
47 #include <linux/ratelimit.h>
48 #include <linux/seccomp.h>
49 #include <linux/if_vlan.h>
50 #include <linux/bpf.h>
51 #include <linux/btf.h>
52 #include <net/sch_generic.h>
53 #include <net/cls_cgroup.h>
54 #include <net/dst_metadata.h>
55 #include <net/dst.h>
56 #include <net/sock_reuseport.h>
57 #include <net/busy_poll.h>
58 #include <net/tcp.h>
59 #include <net/xfrm.h>
60 #include <net/udp.h>
61 #include <linux/bpf_trace.h>
62 #include <net/xdp_sock.h>
63 #include <linux/inetdevice.h>
64 #include <net/inet_hashtables.h>
65 #include <net/inet6_hashtables.h>
66 #include <net/ip_fib.h>
67 #include <net/nexthop.h>
68 #include <net/flow.h>
69 #include <net/arp.h>
70 #include <net/ipv6.h>
71 #include <net/net_namespace.h>
72 #include <linux/seg6_local.h>
73 #include <net/seg6.h>
74 #include <net/seg6_local.h>
75 #include <net/lwtunnel.h>
76 #include <net/ipv6_stubs.h>
77 #include <net/bpf_sk_storage.h>
78 #include <net/transp_v6.h>
79 #include <linux/btf_ids.h>
80 #include <net/tls.h>
81 #include <net/xdp.h>
82 #include <net/mptcp.h>
83 #include <net/netfilter/nf_conntrack_bpf.h>
84 #include <linux/un.h>
85 #include <net/xdp_sock_drv.h>
86 
87 static const struct bpf_func_proto *
88 bpf_sk_base_func_proto(enum bpf_func_id func_id);
89 
copy_bpf_fprog_from_user(struct sock_fprog * dst,sockptr_t src,int len)90 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len)
91 {
92 	if (in_compat_syscall()) {
93 		struct compat_sock_fprog f32;
94 
95 		if (len != sizeof(f32))
96 			return -EINVAL;
97 		if (copy_from_sockptr(&f32, src, sizeof(f32)))
98 			return -EFAULT;
99 		memset(dst, 0, sizeof(*dst));
100 		dst->len = f32.len;
101 		dst->filter = compat_ptr(f32.filter);
102 	} else {
103 		if (len != sizeof(*dst))
104 			return -EINVAL;
105 		if (copy_from_sockptr(dst, src, sizeof(*dst)))
106 			return -EFAULT;
107 	}
108 
109 	return 0;
110 }
111 EXPORT_SYMBOL_GPL(copy_bpf_fprog_from_user);
112 
113 /**
114  *	sk_filter_trim_cap - run a packet through a socket filter
115  *	@sk: sock associated with &sk_buff
116  *	@skb: buffer to filter
117  *	@cap: limit on how short the eBPF program may trim the packet
118  *
119  * Run the eBPF program and then cut skb->data to correct size returned by
120  * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
121  * than pkt_len we keep whole skb->data. This is the socket level
122  * wrapper to bpf_prog_run. It returns 0 if the packet should
123  * be accepted or -EPERM if the packet should be tossed.
124  *
125  */
sk_filter_trim_cap(struct sock * sk,struct sk_buff * skb,unsigned int cap)126 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
127 {
128 	int err;
129 	struct sk_filter *filter;
130 
131 	/*
132 	 * If the skb was allocated from pfmemalloc reserves, only
133 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
134 	 * helping free memory
135 	 */
136 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
137 		NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
138 		return -ENOMEM;
139 	}
140 	err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
141 	if (err)
142 		return err;
143 
144 	err = security_sock_rcv_skb(sk, skb);
145 	if (err)
146 		return err;
147 
148 	rcu_read_lock();
149 	filter = rcu_dereference(sk->sk_filter);
150 	if (filter) {
151 		struct sock *save_sk = skb->sk;
152 		unsigned int pkt_len;
153 
154 		skb->sk = sk;
155 		pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
156 		skb->sk = save_sk;
157 		err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
158 	}
159 	rcu_read_unlock();
160 
161 	return err;
162 }
163 EXPORT_SYMBOL(sk_filter_trim_cap);
164 
BPF_CALL_1(bpf_skb_get_pay_offset,struct sk_buff *,skb)165 BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb)
166 {
167 	return skb_get_poff(skb);
168 }
169 
BPF_CALL_3(bpf_skb_get_nlattr,struct sk_buff *,skb,u32,a,u32,x)170 BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
171 {
172 	struct nlattr *nla;
173 
174 	if (skb_is_nonlinear(skb))
175 		return 0;
176 
177 	if (skb->len < sizeof(struct nlattr))
178 		return 0;
179 
180 	if (a > skb->len - sizeof(struct nlattr))
181 		return 0;
182 
183 	nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
184 	if (nla)
185 		return (void *) nla - (void *) skb->data;
186 
187 	return 0;
188 }
189 
BPF_CALL_3(bpf_skb_get_nlattr_nest,struct sk_buff *,skb,u32,a,u32,x)190 BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
191 {
192 	struct nlattr *nla;
193 
194 	if (skb_is_nonlinear(skb))
195 		return 0;
196 
197 	if (skb->len < sizeof(struct nlattr))
198 		return 0;
199 
200 	if (a > skb->len - sizeof(struct nlattr))
201 		return 0;
202 
203 	nla = (struct nlattr *) &skb->data[a];
204 	if (nla->nla_len > skb->len - a)
205 		return 0;
206 
207 	nla = nla_find_nested(nla, x);
208 	if (nla)
209 		return (void *) nla - (void *) skb->data;
210 
211 	return 0;
212 }
213 
bpf_skb_load_helper_convert_offset(const struct sk_buff * skb,int offset)214 static int bpf_skb_load_helper_convert_offset(const struct sk_buff *skb, int offset)
215 {
216 	if (likely(offset >= 0))
217 		return offset;
218 
219 	if (offset >= SKF_NET_OFF)
220 		return offset - SKF_NET_OFF + skb_network_offset(skb);
221 
222 	if (offset >= SKF_LL_OFF && skb_mac_header_was_set(skb))
223 		return offset - SKF_LL_OFF + skb_mac_offset(skb);
224 
225 	return INT_MIN;
226 }
227 
BPF_CALL_4(bpf_skb_load_helper_8,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)228 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
229 	   data, int, headlen, int, offset)
230 {
231 	u8 tmp;
232 	const int len = sizeof(tmp);
233 
234 	offset = bpf_skb_load_helper_convert_offset(skb, offset);
235 	if (offset == INT_MIN)
236 		return -EFAULT;
237 
238 	if (headlen - offset >= len)
239 		return *(u8 *)(data + offset);
240 	if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
241 		return tmp;
242 	else
243 		return -EFAULT;
244 }
245 
BPF_CALL_2(bpf_skb_load_helper_8_no_cache,const struct sk_buff *,skb,int,offset)246 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
247 	   int, offset)
248 {
249 	return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
250 					 offset);
251 }
252 
BPF_CALL_4(bpf_skb_load_helper_16,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)253 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
254 	   data, int, headlen, int, offset)
255 {
256 	__be16 tmp;
257 	const int len = sizeof(tmp);
258 
259 	offset = bpf_skb_load_helper_convert_offset(skb, offset);
260 	if (offset == INT_MIN)
261 		return -EFAULT;
262 
263 	if (headlen - offset >= len)
264 		return get_unaligned_be16(data + offset);
265 	if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
266 		return be16_to_cpu(tmp);
267 	else
268 		return -EFAULT;
269 }
270 
BPF_CALL_2(bpf_skb_load_helper_16_no_cache,const struct sk_buff *,skb,int,offset)271 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
272 	   int, offset)
273 {
274 	return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
275 					  offset);
276 }
277 
BPF_CALL_4(bpf_skb_load_helper_32,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)278 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
279 	   data, int, headlen, int, offset)
280 {
281 	__be32 tmp;
282 	const int len = sizeof(tmp);
283 
284 	offset = bpf_skb_load_helper_convert_offset(skb, offset);
285 	if (offset == INT_MIN)
286 		return -EFAULT;
287 
288 	if (headlen - offset >= len)
289 		return get_unaligned_be32(data + offset);
290 	if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
291 		return be32_to_cpu(tmp);
292 	else
293 		return -EFAULT;
294 }
295 
BPF_CALL_2(bpf_skb_load_helper_32_no_cache,const struct sk_buff *,skb,int,offset)296 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
297 	   int, offset)
298 {
299 	return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
300 					  offset);
301 }
302 
convert_skb_access(int skb_field,int dst_reg,int src_reg,struct bpf_insn * insn_buf)303 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
304 			      struct bpf_insn *insn_buf)
305 {
306 	struct bpf_insn *insn = insn_buf;
307 
308 	switch (skb_field) {
309 	case SKF_AD_MARK:
310 		BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4);
311 
312 		*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
313 				      offsetof(struct sk_buff, mark));
314 		break;
315 
316 	case SKF_AD_PKTTYPE:
317 		*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET);
318 		*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
319 #ifdef __BIG_ENDIAN_BITFIELD
320 		*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
321 #endif
322 		break;
323 
324 	case SKF_AD_QUEUE:
325 		BUILD_BUG_ON(sizeof_field(struct sk_buff, queue_mapping) != 2);
326 
327 		*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
328 				      offsetof(struct sk_buff, queue_mapping));
329 		break;
330 
331 	case SKF_AD_VLAN_TAG:
332 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_tci) != 2);
333 
334 		/* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
335 		*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
336 				      offsetof(struct sk_buff, vlan_tci));
337 		break;
338 	case SKF_AD_VLAN_TAG_PRESENT:
339 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_all) != 4);
340 		*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
341 				      offsetof(struct sk_buff, vlan_all));
342 		*insn++ = BPF_JMP_IMM(BPF_JEQ, dst_reg, 0, 1);
343 		*insn++ = BPF_ALU32_IMM(BPF_MOV, dst_reg, 1);
344 		break;
345 	}
346 
347 	return insn - insn_buf;
348 }
349 
convert_bpf_extensions(struct sock_filter * fp,struct bpf_insn ** insnp)350 static bool convert_bpf_extensions(struct sock_filter *fp,
351 				   struct bpf_insn **insnp)
352 {
353 	struct bpf_insn *insn = *insnp;
354 	u32 cnt;
355 
356 	switch (fp->k) {
357 	case SKF_AD_OFF + SKF_AD_PROTOCOL:
358 		BUILD_BUG_ON(sizeof_field(struct sk_buff, protocol) != 2);
359 
360 		/* A = *(u16 *) (CTX + offsetof(protocol)) */
361 		*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
362 				      offsetof(struct sk_buff, protocol));
363 		/* A = ntohs(A) [emitting a nop or swap16] */
364 		*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
365 		break;
366 
367 	case SKF_AD_OFF + SKF_AD_PKTTYPE:
368 		cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
369 		insn += cnt - 1;
370 		break;
371 
372 	case SKF_AD_OFF + SKF_AD_IFINDEX:
373 	case SKF_AD_OFF + SKF_AD_HATYPE:
374 		BUILD_BUG_ON(sizeof_field(struct net_device, ifindex) != 4);
375 		BUILD_BUG_ON(sizeof_field(struct net_device, type) != 2);
376 
377 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
378 				      BPF_REG_TMP, BPF_REG_CTX,
379 				      offsetof(struct sk_buff, dev));
380 		/* if (tmp != 0) goto pc + 1 */
381 		*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
382 		*insn++ = BPF_EXIT_INSN();
383 		if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
384 			*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
385 					    offsetof(struct net_device, ifindex));
386 		else
387 			*insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
388 					    offsetof(struct net_device, type));
389 		break;
390 
391 	case SKF_AD_OFF + SKF_AD_MARK:
392 		cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
393 		insn += cnt - 1;
394 		break;
395 
396 	case SKF_AD_OFF + SKF_AD_RXHASH:
397 		BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4);
398 
399 		*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
400 				    offsetof(struct sk_buff, hash));
401 		break;
402 
403 	case SKF_AD_OFF + SKF_AD_QUEUE:
404 		cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
405 		insn += cnt - 1;
406 		break;
407 
408 	case SKF_AD_OFF + SKF_AD_VLAN_TAG:
409 		cnt = convert_skb_access(SKF_AD_VLAN_TAG,
410 					 BPF_REG_A, BPF_REG_CTX, insn);
411 		insn += cnt - 1;
412 		break;
413 
414 	case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
415 		cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
416 					 BPF_REG_A, BPF_REG_CTX, insn);
417 		insn += cnt - 1;
418 		break;
419 
420 	case SKF_AD_OFF + SKF_AD_VLAN_TPID:
421 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_proto) != 2);
422 
423 		/* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
424 		*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
425 				      offsetof(struct sk_buff, vlan_proto));
426 		/* A = ntohs(A) [emitting a nop or swap16] */
427 		*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
428 		break;
429 
430 	case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
431 	case SKF_AD_OFF + SKF_AD_NLATTR:
432 	case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
433 	case SKF_AD_OFF + SKF_AD_CPU:
434 	case SKF_AD_OFF + SKF_AD_RANDOM:
435 		/* arg1 = CTX */
436 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
437 		/* arg2 = A */
438 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
439 		/* arg3 = X */
440 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
441 		/* Emit call(arg1=CTX, arg2=A, arg3=X) */
442 		switch (fp->k) {
443 		case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
444 			*insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
445 			break;
446 		case SKF_AD_OFF + SKF_AD_NLATTR:
447 			*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
448 			break;
449 		case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
450 			*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
451 			break;
452 		case SKF_AD_OFF + SKF_AD_CPU:
453 			*insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
454 			break;
455 		case SKF_AD_OFF + SKF_AD_RANDOM:
456 			*insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
457 			bpf_user_rnd_init_once();
458 			break;
459 		}
460 		break;
461 
462 	case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
463 		/* A ^= X */
464 		*insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
465 		break;
466 
467 	default:
468 		/* This is just a dummy call to avoid letting the compiler
469 		 * evict __bpf_call_base() as an optimization. Placed here
470 		 * where no-one bothers.
471 		 */
472 		BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
473 		return false;
474 	}
475 
476 	*insnp = insn;
477 	return true;
478 }
479 
convert_bpf_ld_abs(struct sock_filter * fp,struct bpf_insn ** insnp)480 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
481 {
482 	const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
483 	int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
484 	bool endian = BPF_SIZE(fp->code) == BPF_H ||
485 		      BPF_SIZE(fp->code) == BPF_W;
486 	bool indirect = BPF_MODE(fp->code) == BPF_IND;
487 	const int ip_align = NET_IP_ALIGN;
488 	struct bpf_insn *insn = *insnp;
489 	int offset = fp->k;
490 
491 	if (!indirect &&
492 	    ((unaligned_ok && offset >= 0) ||
493 	     (!unaligned_ok && offset >= 0 &&
494 	      offset + ip_align >= 0 &&
495 	      offset + ip_align % size == 0))) {
496 		bool ldx_off_ok = offset <= S16_MAX;
497 
498 		*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
499 		if (offset)
500 			*insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
501 		*insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
502 				      size, 2 + endian + (!ldx_off_ok * 2));
503 		if (ldx_off_ok) {
504 			*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
505 					      BPF_REG_D, offset);
506 		} else {
507 			*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
508 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
509 			*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
510 					      BPF_REG_TMP, 0);
511 		}
512 		if (endian)
513 			*insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
514 		*insn++ = BPF_JMP_A(8);
515 	}
516 
517 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
518 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
519 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
520 	if (!indirect) {
521 		*insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
522 	} else {
523 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
524 		if (fp->k)
525 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
526 	}
527 
528 	switch (BPF_SIZE(fp->code)) {
529 	case BPF_B:
530 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
531 		break;
532 	case BPF_H:
533 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
534 		break;
535 	case BPF_W:
536 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
537 		break;
538 	default:
539 		return false;
540 	}
541 
542 	*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
543 	*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
544 	*insn   = BPF_EXIT_INSN();
545 
546 	*insnp = insn;
547 	return true;
548 }
549 
550 /**
551  *	bpf_convert_filter - convert filter program
552  *	@prog: the user passed filter program
553  *	@len: the length of the user passed filter program
554  *	@new_prog: allocated 'struct bpf_prog' or NULL
555  *	@new_len: pointer to store length of converted program
556  *	@seen_ld_abs: bool whether we've seen ld_abs/ind
557  *
558  * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
559  * style extended BPF (eBPF).
560  * Conversion workflow:
561  *
562  * 1) First pass for calculating the new program length:
563  *   bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
564  *
565  * 2) 2nd pass to remap in two passes: 1st pass finds new
566  *    jump offsets, 2nd pass remapping:
567  *   bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
568  */
bpf_convert_filter(struct sock_filter * prog,int len,struct bpf_prog * new_prog,int * new_len,bool * seen_ld_abs)569 static int bpf_convert_filter(struct sock_filter *prog, int len,
570 			      struct bpf_prog *new_prog, int *new_len,
571 			      bool *seen_ld_abs)
572 {
573 	int new_flen = 0, pass = 0, target, i, stack_off;
574 	struct bpf_insn *new_insn, *first_insn = NULL;
575 	struct sock_filter *fp;
576 	int *addrs = NULL;
577 	u8 bpf_src;
578 
579 	BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
580 	BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
581 
582 	if (len <= 0 || len > BPF_MAXINSNS)
583 		return -EINVAL;
584 
585 	if (new_prog) {
586 		first_insn = new_prog->insnsi;
587 		addrs = kcalloc(len, sizeof(*addrs),
588 				GFP_KERNEL | __GFP_NOWARN);
589 		if (!addrs)
590 			return -ENOMEM;
591 	}
592 
593 do_pass:
594 	new_insn = first_insn;
595 	fp = prog;
596 
597 	/* Classic BPF related prologue emission. */
598 	if (new_prog) {
599 		/* Classic BPF expects A and X to be reset first. These need
600 		 * to be guaranteed to be the first two instructions.
601 		 */
602 		*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
603 		*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
604 
605 		/* All programs must keep CTX in callee saved BPF_REG_CTX.
606 		 * In eBPF case it's done by the compiler, here we need to
607 		 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
608 		 */
609 		*new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
610 		if (*seen_ld_abs) {
611 			/* For packet access in classic BPF, cache skb->data
612 			 * in callee-saved BPF R8 and skb->len - skb->data_len
613 			 * (headlen) in BPF R9. Since classic BPF is read-only
614 			 * on CTX, we only need to cache it once.
615 			 */
616 			*new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
617 						  BPF_REG_D, BPF_REG_CTX,
618 						  offsetof(struct sk_buff, data));
619 			*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
620 						  offsetof(struct sk_buff, len));
621 			*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
622 						  offsetof(struct sk_buff, data_len));
623 			*new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
624 		}
625 	} else {
626 		new_insn += 3;
627 	}
628 
629 	for (i = 0; i < len; fp++, i++) {
630 		struct bpf_insn tmp_insns[32] = { };
631 		struct bpf_insn *insn = tmp_insns;
632 
633 		if (addrs)
634 			addrs[i] = new_insn - first_insn;
635 
636 		switch (fp->code) {
637 		/* All arithmetic insns and skb loads map as-is. */
638 		case BPF_ALU | BPF_ADD | BPF_X:
639 		case BPF_ALU | BPF_ADD | BPF_K:
640 		case BPF_ALU | BPF_SUB | BPF_X:
641 		case BPF_ALU | BPF_SUB | BPF_K:
642 		case BPF_ALU | BPF_AND | BPF_X:
643 		case BPF_ALU | BPF_AND | BPF_K:
644 		case BPF_ALU | BPF_OR | BPF_X:
645 		case BPF_ALU | BPF_OR | BPF_K:
646 		case BPF_ALU | BPF_LSH | BPF_X:
647 		case BPF_ALU | BPF_LSH | BPF_K:
648 		case BPF_ALU | BPF_RSH | BPF_X:
649 		case BPF_ALU | BPF_RSH | BPF_K:
650 		case BPF_ALU | BPF_XOR | BPF_X:
651 		case BPF_ALU | BPF_XOR | BPF_K:
652 		case BPF_ALU | BPF_MUL | BPF_X:
653 		case BPF_ALU | BPF_MUL | BPF_K:
654 		case BPF_ALU | BPF_DIV | BPF_X:
655 		case BPF_ALU | BPF_DIV | BPF_K:
656 		case BPF_ALU | BPF_MOD | BPF_X:
657 		case BPF_ALU | BPF_MOD | BPF_K:
658 		case BPF_ALU | BPF_NEG:
659 		case BPF_LD | BPF_ABS | BPF_W:
660 		case BPF_LD | BPF_ABS | BPF_H:
661 		case BPF_LD | BPF_ABS | BPF_B:
662 		case BPF_LD | BPF_IND | BPF_W:
663 		case BPF_LD | BPF_IND | BPF_H:
664 		case BPF_LD | BPF_IND | BPF_B:
665 			/* Check for overloaded BPF extension and
666 			 * directly convert it if found, otherwise
667 			 * just move on with mapping.
668 			 */
669 			if (BPF_CLASS(fp->code) == BPF_LD &&
670 			    BPF_MODE(fp->code) == BPF_ABS &&
671 			    convert_bpf_extensions(fp, &insn))
672 				break;
673 			if (BPF_CLASS(fp->code) == BPF_LD &&
674 			    convert_bpf_ld_abs(fp, &insn)) {
675 				*seen_ld_abs = true;
676 				break;
677 			}
678 
679 			if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
680 			    fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
681 				*insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
682 				/* Error with exception code on div/mod by 0.
683 				 * For cBPF programs, this was always return 0.
684 				 */
685 				*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
686 				*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
687 				*insn++ = BPF_EXIT_INSN();
688 			}
689 
690 			*insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
691 			break;
692 
693 		/* Jump transformation cannot use BPF block macros
694 		 * everywhere as offset calculation and target updates
695 		 * require a bit more work than the rest, i.e. jump
696 		 * opcodes map as-is, but offsets need adjustment.
697 		 */
698 
699 #define BPF_EMIT_JMP							\
700 	do {								\
701 		const s32 off_min = S16_MIN, off_max = S16_MAX;		\
702 		s32 off;						\
703 									\
704 		if (target >= len || target < 0)			\
705 			goto err;					\
706 		off = addrs ? addrs[target] - addrs[i] - 1 : 0;		\
707 		/* Adjust pc relative offset for 2nd or 3rd insn. */	\
708 		off -= insn - tmp_insns;				\
709 		/* Reject anything not fitting into insn->off. */	\
710 		if (off < off_min || off > off_max)			\
711 			goto err;					\
712 		insn->off = off;					\
713 	} while (0)
714 
715 		case BPF_JMP | BPF_JA:
716 			target = i + fp->k + 1;
717 			insn->code = fp->code;
718 			BPF_EMIT_JMP;
719 			break;
720 
721 		case BPF_JMP | BPF_JEQ | BPF_K:
722 		case BPF_JMP | BPF_JEQ | BPF_X:
723 		case BPF_JMP | BPF_JSET | BPF_K:
724 		case BPF_JMP | BPF_JSET | BPF_X:
725 		case BPF_JMP | BPF_JGT | BPF_K:
726 		case BPF_JMP | BPF_JGT | BPF_X:
727 		case BPF_JMP | BPF_JGE | BPF_K:
728 		case BPF_JMP | BPF_JGE | BPF_X:
729 			if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
730 				/* BPF immediates are signed, zero extend
731 				 * immediate into tmp register and use it
732 				 * in compare insn.
733 				 */
734 				*insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
735 
736 				insn->dst_reg = BPF_REG_A;
737 				insn->src_reg = BPF_REG_TMP;
738 				bpf_src = BPF_X;
739 			} else {
740 				insn->dst_reg = BPF_REG_A;
741 				insn->imm = fp->k;
742 				bpf_src = BPF_SRC(fp->code);
743 				insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
744 			}
745 
746 			/* Common case where 'jump_false' is next insn. */
747 			if (fp->jf == 0) {
748 				insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
749 				target = i + fp->jt + 1;
750 				BPF_EMIT_JMP;
751 				break;
752 			}
753 
754 			/* Convert some jumps when 'jump_true' is next insn. */
755 			if (fp->jt == 0) {
756 				switch (BPF_OP(fp->code)) {
757 				case BPF_JEQ:
758 					insn->code = BPF_JMP | BPF_JNE | bpf_src;
759 					break;
760 				case BPF_JGT:
761 					insn->code = BPF_JMP | BPF_JLE | bpf_src;
762 					break;
763 				case BPF_JGE:
764 					insn->code = BPF_JMP | BPF_JLT | bpf_src;
765 					break;
766 				default:
767 					goto jmp_rest;
768 				}
769 
770 				target = i + fp->jf + 1;
771 				BPF_EMIT_JMP;
772 				break;
773 			}
774 jmp_rest:
775 			/* Other jumps are mapped into two insns: Jxx and JA. */
776 			target = i + fp->jt + 1;
777 			insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
778 			BPF_EMIT_JMP;
779 			insn++;
780 
781 			insn->code = BPF_JMP | BPF_JA;
782 			target = i + fp->jf + 1;
783 			BPF_EMIT_JMP;
784 			break;
785 
786 		/* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
787 		case BPF_LDX | BPF_MSH | BPF_B: {
788 			struct sock_filter tmp = {
789 				.code	= BPF_LD | BPF_ABS | BPF_B,
790 				.k	= fp->k,
791 			};
792 
793 			*seen_ld_abs = true;
794 
795 			/* X = A */
796 			*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
797 			/* A = BPF_R0 = *(u8 *) (skb->data + K) */
798 			convert_bpf_ld_abs(&tmp, &insn);
799 			insn++;
800 			/* A &= 0xf */
801 			*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
802 			/* A <<= 2 */
803 			*insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
804 			/* tmp = X */
805 			*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
806 			/* X = A */
807 			*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
808 			/* A = tmp */
809 			*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
810 			break;
811 		}
812 		/* RET_K is remaped into 2 insns. RET_A case doesn't need an
813 		 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
814 		 */
815 		case BPF_RET | BPF_A:
816 		case BPF_RET | BPF_K:
817 			if (BPF_RVAL(fp->code) == BPF_K)
818 				*insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
819 							0, fp->k);
820 			*insn = BPF_EXIT_INSN();
821 			break;
822 
823 		/* Store to stack. */
824 		case BPF_ST:
825 		case BPF_STX:
826 			stack_off = fp->k * 4  + 4;
827 			*insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
828 					    BPF_ST ? BPF_REG_A : BPF_REG_X,
829 					    -stack_off);
830 			/* check_load_and_stores() verifies that classic BPF can
831 			 * load from stack only after write, so tracking
832 			 * stack_depth for ST|STX insns is enough
833 			 */
834 			if (new_prog && new_prog->aux->stack_depth < stack_off)
835 				new_prog->aux->stack_depth = stack_off;
836 			break;
837 
838 		/* Load from stack. */
839 		case BPF_LD | BPF_MEM:
840 		case BPF_LDX | BPF_MEM:
841 			stack_off = fp->k * 4  + 4;
842 			*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD  ?
843 					    BPF_REG_A : BPF_REG_X, BPF_REG_FP,
844 					    -stack_off);
845 			break;
846 
847 		/* A = K or X = K */
848 		case BPF_LD | BPF_IMM:
849 		case BPF_LDX | BPF_IMM:
850 			*insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
851 					      BPF_REG_A : BPF_REG_X, fp->k);
852 			break;
853 
854 		/* X = A */
855 		case BPF_MISC | BPF_TAX:
856 			*insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
857 			break;
858 
859 		/* A = X */
860 		case BPF_MISC | BPF_TXA:
861 			*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
862 			break;
863 
864 		/* A = skb->len or X = skb->len */
865 		case BPF_LD | BPF_W | BPF_LEN:
866 		case BPF_LDX | BPF_W | BPF_LEN:
867 			*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
868 					    BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
869 					    offsetof(struct sk_buff, len));
870 			break;
871 
872 		/* Access seccomp_data fields. */
873 		case BPF_LDX | BPF_ABS | BPF_W:
874 			/* A = *(u32 *) (ctx + K) */
875 			*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
876 			break;
877 
878 		/* Unknown instruction. */
879 		default:
880 			goto err;
881 		}
882 
883 		insn++;
884 		if (new_prog)
885 			memcpy(new_insn, tmp_insns,
886 			       sizeof(*insn) * (insn - tmp_insns));
887 		new_insn += insn - tmp_insns;
888 	}
889 
890 	if (!new_prog) {
891 		/* Only calculating new length. */
892 		*new_len = new_insn - first_insn;
893 		if (*seen_ld_abs)
894 			*new_len += 4; /* Prologue bits. */
895 		return 0;
896 	}
897 
898 	pass++;
899 	if (new_flen != new_insn - first_insn) {
900 		new_flen = new_insn - first_insn;
901 		if (pass > 2)
902 			goto err;
903 		goto do_pass;
904 	}
905 
906 	kfree(addrs);
907 	BUG_ON(*new_len != new_flen);
908 	return 0;
909 err:
910 	kfree(addrs);
911 	return -EINVAL;
912 }
913 
914 /* Security:
915  *
916  * As we dont want to clear mem[] array for each packet going through
917  * __bpf_prog_run(), we check that filter loaded by user never try to read
918  * a cell if not previously written, and we check all branches to be sure
919  * a malicious user doesn't try to abuse us.
920  */
check_load_and_stores(const struct sock_filter * filter,int flen)921 static int check_load_and_stores(const struct sock_filter *filter, int flen)
922 {
923 	u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
924 	int pc, ret = 0;
925 
926 	BUILD_BUG_ON(BPF_MEMWORDS > 16);
927 
928 	masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
929 	if (!masks)
930 		return -ENOMEM;
931 
932 	memset(masks, 0xff, flen * sizeof(*masks));
933 
934 	for (pc = 0; pc < flen; pc++) {
935 		memvalid &= masks[pc];
936 
937 		switch (filter[pc].code) {
938 		case BPF_ST:
939 		case BPF_STX:
940 			memvalid |= (1 << filter[pc].k);
941 			break;
942 		case BPF_LD | BPF_MEM:
943 		case BPF_LDX | BPF_MEM:
944 			if (!(memvalid & (1 << filter[pc].k))) {
945 				ret = -EINVAL;
946 				goto error;
947 			}
948 			break;
949 		case BPF_JMP | BPF_JA:
950 			/* A jump must set masks on target */
951 			masks[pc + 1 + filter[pc].k] &= memvalid;
952 			memvalid = ~0;
953 			break;
954 		case BPF_JMP | BPF_JEQ | BPF_K:
955 		case BPF_JMP | BPF_JEQ | BPF_X:
956 		case BPF_JMP | BPF_JGE | BPF_K:
957 		case BPF_JMP | BPF_JGE | BPF_X:
958 		case BPF_JMP | BPF_JGT | BPF_K:
959 		case BPF_JMP | BPF_JGT | BPF_X:
960 		case BPF_JMP | BPF_JSET | BPF_K:
961 		case BPF_JMP | BPF_JSET | BPF_X:
962 			/* A jump must set masks on targets */
963 			masks[pc + 1 + filter[pc].jt] &= memvalid;
964 			masks[pc + 1 + filter[pc].jf] &= memvalid;
965 			memvalid = ~0;
966 			break;
967 		}
968 	}
969 error:
970 	kfree(masks);
971 	return ret;
972 }
973 
chk_code_allowed(u16 code_to_probe)974 static bool chk_code_allowed(u16 code_to_probe)
975 {
976 	static const bool codes[] = {
977 		/* 32 bit ALU operations */
978 		[BPF_ALU | BPF_ADD | BPF_K] = true,
979 		[BPF_ALU | BPF_ADD | BPF_X] = true,
980 		[BPF_ALU | BPF_SUB | BPF_K] = true,
981 		[BPF_ALU | BPF_SUB | BPF_X] = true,
982 		[BPF_ALU | BPF_MUL | BPF_K] = true,
983 		[BPF_ALU | BPF_MUL | BPF_X] = true,
984 		[BPF_ALU | BPF_DIV | BPF_K] = true,
985 		[BPF_ALU | BPF_DIV | BPF_X] = true,
986 		[BPF_ALU | BPF_MOD | BPF_K] = true,
987 		[BPF_ALU | BPF_MOD | BPF_X] = true,
988 		[BPF_ALU | BPF_AND | BPF_K] = true,
989 		[BPF_ALU | BPF_AND | BPF_X] = true,
990 		[BPF_ALU | BPF_OR | BPF_K] = true,
991 		[BPF_ALU | BPF_OR | BPF_X] = true,
992 		[BPF_ALU | BPF_XOR | BPF_K] = true,
993 		[BPF_ALU | BPF_XOR | BPF_X] = true,
994 		[BPF_ALU | BPF_LSH | BPF_K] = true,
995 		[BPF_ALU | BPF_LSH | BPF_X] = true,
996 		[BPF_ALU | BPF_RSH | BPF_K] = true,
997 		[BPF_ALU | BPF_RSH | BPF_X] = true,
998 		[BPF_ALU | BPF_NEG] = true,
999 		/* Load instructions */
1000 		[BPF_LD | BPF_W | BPF_ABS] = true,
1001 		[BPF_LD | BPF_H | BPF_ABS] = true,
1002 		[BPF_LD | BPF_B | BPF_ABS] = true,
1003 		[BPF_LD | BPF_W | BPF_LEN] = true,
1004 		[BPF_LD | BPF_W | BPF_IND] = true,
1005 		[BPF_LD | BPF_H | BPF_IND] = true,
1006 		[BPF_LD | BPF_B | BPF_IND] = true,
1007 		[BPF_LD | BPF_IMM] = true,
1008 		[BPF_LD | BPF_MEM] = true,
1009 		[BPF_LDX | BPF_W | BPF_LEN] = true,
1010 		[BPF_LDX | BPF_B | BPF_MSH] = true,
1011 		[BPF_LDX | BPF_IMM] = true,
1012 		[BPF_LDX | BPF_MEM] = true,
1013 		/* Store instructions */
1014 		[BPF_ST] = true,
1015 		[BPF_STX] = true,
1016 		/* Misc instructions */
1017 		[BPF_MISC | BPF_TAX] = true,
1018 		[BPF_MISC | BPF_TXA] = true,
1019 		/* Return instructions */
1020 		[BPF_RET | BPF_K] = true,
1021 		[BPF_RET | BPF_A] = true,
1022 		/* Jump instructions */
1023 		[BPF_JMP | BPF_JA] = true,
1024 		[BPF_JMP | BPF_JEQ | BPF_K] = true,
1025 		[BPF_JMP | BPF_JEQ | BPF_X] = true,
1026 		[BPF_JMP | BPF_JGE | BPF_K] = true,
1027 		[BPF_JMP | BPF_JGE | BPF_X] = true,
1028 		[BPF_JMP | BPF_JGT | BPF_K] = true,
1029 		[BPF_JMP | BPF_JGT | BPF_X] = true,
1030 		[BPF_JMP | BPF_JSET | BPF_K] = true,
1031 		[BPF_JMP | BPF_JSET | BPF_X] = true,
1032 	};
1033 
1034 	if (code_to_probe >= ARRAY_SIZE(codes))
1035 		return false;
1036 
1037 	return codes[code_to_probe];
1038 }
1039 
bpf_check_basics_ok(const struct sock_filter * filter,unsigned int flen)1040 static bool bpf_check_basics_ok(const struct sock_filter *filter,
1041 				unsigned int flen)
1042 {
1043 	if (filter == NULL)
1044 		return false;
1045 	if (flen == 0 || flen > BPF_MAXINSNS)
1046 		return false;
1047 
1048 	return true;
1049 }
1050 
1051 /**
1052  *	bpf_check_classic - verify socket filter code
1053  *	@filter: filter to verify
1054  *	@flen: length of filter
1055  *
1056  * Check the user's filter code. If we let some ugly
1057  * filter code slip through kaboom! The filter must contain
1058  * no references or jumps that are out of range, no illegal
1059  * instructions, and must end with a RET instruction.
1060  *
1061  * All jumps are forward as they are not signed.
1062  *
1063  * Returns 0 if the rule set is legal or -EINVAL if not.
1064  */
bpf_check_classic(const struct sock_filter * filter,unsigned int flen)1065 static int bpf_check_classic(const struct sock_filter *filter,
1066 			     unsigned int flen)
1067 {
1068 	bool anc_found;
1069 	int pc;
1070 
1071 	/* Check the filter code now */
1072 	for (pc = 0; pc < flen; pc++) {
1073 		const struct sock_filter *ftest = &filter[pc];
1074 
1075 		/* May we actually operate on this code? */
1076 		if (!chk_code_allowed(ftest->code))
1077 			return -EINVAL;
1078 
1079 		/* Some instructions need special checks */
1080 		switch (ftest->code) {
1081 		case BPF_ALU | BPF_DIV | BPF_K:
1082 		case BPF_ALU | BPF_MOD | BPF_K:
1083 			/* Check for division by zero */
1084 			if (ftest->k == 0)
1085 				return -EINVAL;
1086 			break;
1087 		case BPF_ALU | BPF_LSH | BPF_K:
1088 		case BPF_ALU | BPF_RSH | BPF_K:
1089 			if (ftest->k >= 32)
1090 				return -EINVAL;
1091 			break;
1092 		case BPF_LD | BPF_MEM:
1093 		case BPF_LDX | BPF_MEM:
1094 		case BPF_ST:
1095 		case BPF_STX:
1096 			/* Check for invalid memory addresses */
1097 			if (ftest->k >= BPF_MEMWORDS)
1098 				return -EINVAL;
1099 			break;
1100 		case BPF_JMP | BPF_JA:
1101 			/* Note, the large ftest->k might cause loops.
1102 			 * Compare this with conditional jumps below,
1103 			 * where offsets are limited. --ANK (981016)
1104 			 */
1105 			if (ftest->k >= (unsigned int)(flen - pc - 1))
1106 				return -EINVAL;
1107 			break;
1108 		case BPF_JMP | BPF_JEQ | BPF_K:
1109 		case BPF_JMP | BPF_JEQ | BPF_X:
1110 		case BPF_JMP | BPF_JGE | BPF_K:
1111 		case BPF_JMP | BPF_JGE | BPF_X:
1112 		case BPF_JMP | BPF_JGT | BPF_K:
1113 		case BPF_JMP | BPF_JGT | BPF_X:
1114 		case BPF_JMP | BPF_JSET | BPF_K:
1115 		case BPF_JMP | BPF_JSET | BPF_X:
1116 			/* Both conditionals must be safe */
1117 			if (pc + ftest->jt + 1 >= flen ||
1118 			    pc + ftest->jf + 1 >= flen)
1119 				return -EINVAL;
1120 			break;
1121 		case BPF_LD | BPF_W | BPF_ABS:
1122 		case BPF_LD | BPF_H | BPF_ABS:
1123 		case BPF_LD | BPF_B | BPF_ABS:
1124 			anc_found = false;
1125 			if (bpf_anc_helper(ftest) & BPF_ANC)
1126 				anc_found = true;
1127 			/* Ancillary operation unknown or unsupported */
1128 			if (anc_found == false && ftest->k >= SKF_AD_OFF)
1129 				return -EINVAL;
1130 		}
1131 	}
1132 
1133 	/* Last instruction must be a RET code */
1134 	switch (filter[flen - 1].code) {
1135 	case BPF_RET | BPF_K:
1136 	case BPF_RET | BPF_A:
1137 		return check_load_and_stores(filter, flen);
1138 	}
1139 
1140 	return -EINVAL;
1141 }
1142 
bpf_prog_store_orig_filter(struct bpf_prog * fp,const struct sock_fprog * fprog)1143 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
1144 				      const struct sock_fprog *fprog)
1145 {
1146 	unsigned int fsize = bpf_classic_proglen(fprog);
1147 	struct sock_fprog_kern *fkprog;
1148 
1149 	fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
1150 	if (!fp->orig_prog)
1151 		return -ENOMEM;
1152 
1153 	fkprog = fp->orig_prog;
1154 	fkprog->len = fprog->len;
1155 
1156 	fkprog->filter = kmemdup(fp->insns, fsize,
1157 				 GFP_KERNEL | __GFP_NOWARN);
1158 	if (!fkprog->filter) {
1159 		kfree(fp->orig_prog);
1160 		return -ENOMEM;
1161 	}
1162 
1163 	return 0;
1164 }
1165 
bpf_release_orig_filter(struct bpf_prog * fp)1166 static void bpf_release_orig_filter(struct bpf_prog *fp)
1167 {
1168 	struct sock_fprog_kern *fprog = fp->orig_prog;
1169 
1170 	if (fprog) {
1171 		kfree(fprog->filter);
1172 		kfree(fprog);
1173 	}
1174 }
1175 
__bpf_prog_release(struct bpf_prog * prog)1176 static void __bpf_prog_release(struct bpf_prog *prog)
1177 {
1178 	if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
1179 		bpf_prog_put(prog);
1180 	} else {
1181 		bpf_release_orig_filter(prog);
1182 		bpf_prog_free(prog);
1183 	}
1184 }
1185 
__sk_filter_release(struct sk_filter * fp)1186 static void __sk_filter_release(struct sk_filter *fp)
1187 {
1188 	__bpf_prog_release(fp->prog);
1189 	kfree(fp);
1190 }
1191 
1192 /**
1193  * 	sk_filter_release_rcu - Release a socket filter by rcu_head
1194  *	@rcu: rcu_head that contains the sk_filter to free
1195  */
sk_filter_release_rcu(struct rcu_head * rcu)1196 static void sk_filter_release_rcu(struct rcu_head *rcu)
1197 {
1198 	struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
1199 
1200 	__sk_filter_release(fp);
1201 }
1202 
1203 /**
1204  *	sk_filter_release - release a socket filter
1205  *	@fp: filter to remove
1206  *
1207  *	Remove a filter from a socket and release its resources.
1208  */
sk_filter_release(struct sk_filter * fp)1209 static void sk_filter_release(struct sk_filter *fp)
1210 {
1211 	if (refcount_dec_and_test(&fp->refcnt))
1212 		call_rcu(&fp->rcu, sk_filter_release_rcu);
1213 }
1214 
sk_filter_uncharge(struct sock * sk,struct sk_filter * fp)1215 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1216 {
1217 	u32 filter_size = bpf_prog_size(fp->prog->len);
1218 
1219 	atomic_sub(filter_size, &sk->sk_omem_alloc);
1220 	sk_filter_release(fp);
1221 }
1222 
1223 /* try to charge the socket memory if there is space available
1224  * return true on success
1225  */
__sk_filter_charge(struct sock * sk,struct sk_filter * fp)1226 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1227 {
1228 	u32 filter_size = bpf_prog_size(fp->prog->len);
1229 	int optmem_max = READ_ONCE(sysctl_optmem_max);
1230 
1231 	/* same check as in sock_kmalloc() */
1232 	if (filter_size <= optmem_max &&
1233 	    atomic_read(&sk->sk_omem_alloc) + filter_size < optmem_max) {
1234 		atomic_add(filter_size, &sk->sk_omem_alloc);
1235 		return true;
1236 	}
1237 	return false;
1238 }
1239 
sk_filter_charge(struct sock * sk,struct sk_filter * fp)1240 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1241 {
1242 	if (!refcount_inc_not_zero(&fp->refcnt))
1243 		return false;
1244 
1245 	if (!__sk_filter_charge(sk, fp)) {
1246 		sk_filter_release(fp);
1247 		return false;
1248 	}
1249 	return true;
1250 }
1251 
bpf_migrate_filter(struct bpf_prog * fp)1252 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1253 {
1254 	struct sock_filter *old_prog;
1255 	struct bpf_prog *old_fp;
1256 	int err, new_len, old_len = fp->len;
1257 	bool seen_ld_abs = false;
1258 
1259 	/* We are free to overwrite insns et al right here as it won't be used at
1260 	 * this point in time anymore internally after the migration to the eBPF
1261 	 * instruction representation.
1262 	 */
1263 	BUILD_BUG_ON(sizeof(struct sock_filter) !=
1264 		     sizeof(struct bpf_insn));
1265 
1266 	/* Conversion cannot happen on overlapping memory areas,
1267 	 * so we need to keep the user BPF around until the 2nd
1268 	 * pass. At this time, the user BPF is stored in fp->insns.
1269 	 */
1270 	old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1271 			   GFP_KERNEL | __GFP_NOWARN);
1272 	if (!old_prog) {
1273 		err = -ENOMEM;
1274 		goto out_err;
1275 	}
1276 
1277 	/* 1st pass: calculate the new program length. */
1278 	err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
1279 				 &seen_ld_abs);
1280 	if (err)
1281 		goto out_err_free;
1282 
1283 	/* Expand fp for appending the new filter representation. */
1284 	old_fp = fp;
1285 	fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1286 	if (!fp) {
1287 		/* The old_fp is still around in case we couldn't
1288 		 * allocate new memory, so uncharge on that one.
1289 		 */
1290 		fp = old_fp;
1291 		err = -ENOMEM;
1292 		goto out_err_free;
1293 	}
1294 
1295 	fp->len = new_len;
1296 
1297 	/* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1298 	err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
1299 				 &seen_ld_abs);
1300 	if (err)
1301 		/* 2nd bpf_convert_filter() can fail only if it fails
1302 		 * to allocate memory, remapping must succeed. Note,
1303 		 * that at this time old_fp has already been released
1304 		 * by krealloc().
1305 		 */
1306 		goto out_err_free;
1307 
1308 	fp = bpf_prog_select_runtime(fp, &err);
1309 	if (err)
1310 		goto out_err_free;
1311 
1312 	kfree(old_prog);
1313 	return fp;
1314 
1315 out_err_free:
1316 	kfree(old_prog);
1317 out_err:
1318 	__bpf_prog_release(fp);
1319 	return ERR_PTR(err);
1320 }
1321 
bpf_prepare_filter(struct bpf_prog * fp,bpf_aux_classic_check_t trans)1322 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1323 					   bpf_aux_classic_check_t trans)
1324 {
1325 	int err;
1326 
1327 	fp->bpf_func = NULL;
1328 	fp->jited = 0;
1329 
1330 	err = bpf_check_classic(fp->insns, fp->len);
1331 	if (err) {
1332 		__bpf_prog_release(fp);
1333 		return ERR_PTR(err);
1334 	}
1335 
1336 	/* There might be additional checks and transformations
1337 	 * needed on classic filters, f.e. in case of seccomp.
1338 	 */
1339 	if (trans) {
1340 		err = trans(fp->insns, fp->len);
1341 		if (err) {
1342 			__bpf_prog_release(fp);
1343 			return ERR_PTR(err);
1344 		}
1345 	}
1346 
1347 	/* Probe if we can JIT compile the filter and if so, do
1348 	 * the compilation of the filter.
1349 	 */
1350 	bpf_jit_compile(fp);
1351 
1352 	/* JIT compiler couldn't process this filter, so do the eBPF translation
1353 	 * for the optimized interpreter.
1354 	 */
1355 	if (!fp->jited)
1356 		fp = bpf_migrate_filter(fp);
1357 
1358 	return fp;
1359 }
1360 
1361 /**
1362  *	bpf_prog_create - create an unattached filter
1363  *	@pfp: the unattached filter that is created
1364  *	@fprog: the filter program
1365  *
1366  * Create a filter independent of any socket. We first run some
1367  * sanity checks on it to make sure it does not explode on us later.
1368  * If an error occurs or there is insufficient memory for the filter
1369  * a negative errno code is returned. On success the return is zero.
1370  */
bpf_prog_create(struct bpf_prog ** pfp,struct sock_fprog_kern * fprog)1371 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1372 {
1373 	unsigned int fsize = bpf_classic_proglen(fprog);
1374 	struct bpf_prog *fp;
1375 
1376 	/* Make sure new filter is there and in the right amounts. */
1377 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1378 		return -EINVAL;
1379 
1380 	fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1381 	if (!fp)
1382 		return -ENOMEM;
1383 
1384 	memcpy(fp->insns, fprog->filter, fsize);
1385 
1386 	fp->len = fprog->len;
1387 	/* Since unattached filters are not copied back to user
1388 	 * space through sk_get_filter(), we do not need to hold
1389 	 * a copy here, and can spare us the work.
1390 	 */
1391 	fp->orig_prog = NULL;
1392 
1393 	/* bpf_prepare_filter() already takes care of freeing
1394 	 * memory in case something goes wrong.
1395 	 */
1396 	fp = bpf_prepare_filter(fp, NULL);
1397 	if (IS_ERR(fp))
1398 		return PTR_ERR(fp);
1399 
1400 	*pfp = fp;
1401 	return 0;
1402 }
1403 EXPORT_SYMBOL_GPL(bpf_prog_create);
1404 
1405 /**
1406  *	bpf_prog_create_from_user - create an unattached filter from user buffer
1407  *	@pfp: the unattached filter that is created
1408  *	@fprog: the filter program
1409  *	@trans: post-classic verifier transformation handler
1410  *	@save_orig: save classic BPF program
1411  *
1412  * This function effectively does the same as bpf_prog_create(), only
1413  * that it builds up its insns buffer from user space provided buffer.
1414  * It also allows for passing a bpf_aux_classic_check_t handler.
1415  */
bpf_prog_create_from_user(struct bpf_prog ** pfp,struct sock_fprog * fprog,bpf_aux_classic_check_t trans,bool save_orig)1416 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1417 			      bpf_aux_classic_check_t trans, bool save_orig)
1418 {
1419 	unsigned int fsize = bpf_classic_proglen(fprog);
1420 	struct bpf_prog *fp;
1421 	int err;
1422 
1423 	/* Make sure new filter is there and in the right amounts. */
1424 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1425 		return -EINVAL;
1426 
1427 	fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1428 	if (!fp)
1429 		return -ENOMEM;
1430 
1431 	if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1432 		__bpf_prog_free(fp);
1433 		return -EFAULT;
1434 	}
1435 
1436 	fp->len = fprog->len;
1437 	fp->orig_prog = NULL;
1438 
1439 	if (save_orig) {
1440 		err = bpf_prog_store_orig_filter(fp, fprog);
1441 		if (err) {
1442 			__bpf_prog_free(fp);
1443 			return -ENOMEM;
1444 		}
1445 	}
1446 
1447 	/* bpf_prepare_filter() already takes care of freeing
1448 	 * memory in case something goes wrong.
1449 	 */
1450 	fp = bpf_prepare_filter(fp, trans);
1451 	if (IS_ERR(fp))
1452 		return PTR_ERR(fp);
1453 
1454 	*pfp = fp;
1455 	return 0;
1456 }
1457 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1458 
bpf_prog_destroy(struct bpf_prog * fp)1459 void bpf_prog_destroy(struct bpf_prog *fp)
1460 {
1461 	__bpf_prog_release(fp);
1462 }
1463 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1464 
__sk_attach_prog(struct bpf_prog * prog,struct sock * sk)1465 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1466 {
1467 	struct sk_filter *fp, *old_fp;
1468 
1469 	fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1470 	if (!fp)
1471 		return -ENOMEM;
1472 
1473 	fp->prog = prog;
1474 
1475 	if (!__sk_filter_charge(sk, fp)) {
1476 		kfree(fp);
1477 		return -ENOMEM;
1478 	}
1479 	refcount_set(&fp->refcnt, 1);
1480 
1481 	old_fp = rcu_dereference_protected(sk->sk_filter,
1482 					   lockdep_sock_is_held(sk));
1483 	rcu_assign_pointer(sk->sk_filter, fp);
1484 
1485 	if (old_fp)
1486 		sk_filter_uncharge(sk, old_fp);
1487 
1488 	return 0;
1489 }
1490 
1491 static
__get_filter(struct sock_fprog * fprog,struct sock * sk)1492 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1493 {
1494 	unsigned int fsize = bpf_classic_proglen(fprog);
1495 	struct bpf_prog *prog;
1496 	int err;
1497 
1498 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1499 		return ERR_PTR(-EPERM);
1500 
1501 	/* Make sure new filter is there and in the right amounts. */
1502 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1503 		return ERR_PTR(-EINVAL);
1504 
1505 	prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1506 	if (!prog)
1507 		return ERR_PTR(-ENOMEM);
1508 
1509 	if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1510 		__bpf_prog_free(prog);
1511 		return ERR_PTR(-EFAULT);
1512 	}
1513 
1514 	prog->len = fprog->len;
1515 
1516 	err = bpf_prog_store_orig_filter(prog, fprog);
1517 	if (err) {
1518 		__bpf_prog_free(prog);
1519 		return ERR_PTR(-ENOMEM);
1520 	}
1521 
1522 	/* bpf_prepare_filter() already takes care of freeing
1523 	 * memory in case something goes wrong.
1524 	 */
1525 	return bpf_prepare_filter(prog, NULL);
1526 }
1527 
1528 /**
1529  *	sk_attach_filter - attach a socket filter
1530  *	@fprog: the filter program
1531  *	@sk: the socket to use
1532  *
1533  * Attach the user's filter code. We first run some sanity checks on
1534  * it to make sure it does not explode on us later. If an error
1535  * occurs or there is insufficient memory for the filter a negative
1536  * errno code is returned. On success the return is zero.
1537  */
sk_attach_filter(struct sock_fprog * fprog,struct sock * sk)1538 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1539 {
1540 	struct bpf_prog *prog = __get_filter(fprog, sk);
1541 	int err;
1542 
1543 	if (IS_ERR(prog))
1544 		return PTR_ERR(prog);
1545 
1546 	err = __sk_attach_prog(prog, sk);
1547 	if (err < 0) {
1548 		__bpf_prog_release(prog);
1549 		return err;
1550 	}
1551 
1552 	return 0;
1553 }
1554 EXPORT_SYMBOL_GPL(sk_attach_filter);
1555 
sk_reuseport_attach_filter(struct sock_fprog * fprog,struct sock * sk)1556 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1557 {
1558 	struct bpf_prog *prog = __get_filter(fprog, sk);
1559 	int err;
1560 
1561 	if (IS_ERR(prog))
1562 		return PTR_ERR(prog);
1563 
1564 	if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max))
1565 		err = -ENOMEM;
1566 	else
1567 		err = reuseport_attach_prog(sk, prog);
1568 
1569 	if (err)
1570 		__bpf_prog_release(prog);
1571 
1572 	return err;
1573 }
1574 
__get_bpf(u32 ufd,struct sock * sk)1575 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1576 {
1577 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1578 		return ERR_PTR(-EPERM);
1579 
1580 	return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1581 }
1582 
sk_attach_bpf(u32 ufd,struct sock * sk)1583 int sk_attach_bpf(u32 ufd, struct sock *sk)
1584 {
1585 	struct bpf_prog *prog = __get_bpf(ufd, sk);
1586 	int err;
1587 
1588 	if (IS_ERR(prog))
1589 		return PTR_ERR(prog);
1590 
1591 	err = __sk_attach_prog(prog, sk);
1592 	if (err < 0) {
1593 		bpf_prog_put(prog);
1594 		return err;
1595 	}
1596 
1597 	return 0;
1598 }
1599 
sk_reuseport_attach_bpf(u32 ufd,struct sock * sk)1600 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1601 {
1602 	struct bpf_prog *prog;
1603 	int err;
1604 
1605 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1606 		return -EPERM;
1607 
1608 	prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1609 	if (PTR_ERR(prog) == -EINVAL)
1610 		prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
1611 	if (IS_ERR(prog))
1612 		return PTR_ERR(prog);
1613 
1614 	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
1615 		/* Like other non BPF_PROG_TYPE_SOCKET_FILTER
1616 		 * bpf prog (e.g. sockmap).  It depends on the
1617 		 * limitation imposed by bpf_prog_load().
1618 		 * Hence, sysctl_optmem_max is not checked.
1619 		 */
1620 		if ((sk->sk_type != SOCK_STREAM &&
1621 		     sk->sk_type != SOCK_DGRAM) ||
1622 		    (sk->sk_protocol != IPPROTO_UDP &&
1623 		     sk->sk_protocol != IPPROTO_TCP) ||
1624 		    (sk->sk_family != AF_INET &&
1625 		     sk->sk_family != AF_INET6)) {
1626 			err = -ENOTSUPP;
1627 			goto err_prog_put;
1628 		}
1629 	} else {
1630 		/* BPF_PROG_TYPE_SOCKET_FILTER */
1631 		if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max)) {
1632 			err = -ENOMEM;
1633 			goto err_prog_put;
1634 		}
1635 	}
1636 
1637 	err = reuseport_attach_prog(sk, prog);
1638 err_prog_put:
1639 	if (err)
1640 		bpf_prog_put(prog);
1641 
1642 	return err;
1643 }
1644 
sk_reuseport_prog_free(struct bpf_prog * prog)1645 void sk_reuseport_prog_free(struct bpf_prog *prog)
1646 {
1647 	if (!prog)
1648 		return;
1649 
1650 	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
1651 		bpf_prog_put(prog);
1652 	else
1653 		bpf_prog_destroy(prog);
1654 }
1655 
1656 struct bpf_scratchpad {
1657 	union {
1658 		__be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1659 		u8     buff[MAX_BPF_STACK];
1660 	};
1661 };
1662 
1663 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1664 
__bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1665 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1666 					  unsigned int write_len)
1667 {
1668 #ifdef CONFIG_DEBUG_NET
1669 	/* Avoid a splat in pskb_may_pull_reason() */
1670 	if (write_len > INT_MAX)
1671 		return -EINVAL;
1672 #endif
1673 	return skb_ensure_writable(skb, write_len);
1674 }
1675 
bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1676 static inline int bpf_try_make_writable(struct sk_buff *skb,
1677 					unsigned int write_len)
1678 {
1679 	int err = __bpf_try_make_writable(skb, write_len);
1680 
1681 	bpf_compute_data_pointers(skb);
1682 	return err;
1683 }
1684 
bpf_try_make_head_writable(struct sk_buff * skb)1685 static int bpf_try_make_head_writable(struct sk_buff *skb)
1686 {
1687 	return bpf_try_make_writable(skb, skb_headlen(skb));
1688 }
1689 
bpf_push_mac_rcsum(struct sk_buff * skb)1690 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1691 {
1692 	if (skb_at_tc_ingress(skb))
1693 		skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1694 }
1695 
bpf_pull_mac_rcsum(struct sk_buff * skb)1696 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1697 {
1698 	if (skb_at_tc_ingress(skb))
1699 		skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1700 }
1701 
BPF_CALL_5(bpf_skb_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len,u64,flags)1702 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1703 	   const void *, from, u32, len, u64, flags)
1704 {
1705 	void *ptr;
1706 
1707 	if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1708 		return -EINVAL;
1709 	if (unlikely(offset > INT_MAX))
1710 		return -EFAULT;
1711 	if (unlikely(bpf_try_make_writable(skb, offset + len)))
1712 		return -EFAULT;
1713 
1714 	ptr = skb->data + offset;
1715 	if (flags & BPF_F_RECOMPUTE_CSUM)
1716 		__skb_postpull_rcsum(skb, ptr, len, offset);
1717 
1718 	memcpy(ptr, from, len);
1719 
1720 	if (flags & BPF_F_RECOMPUTE_CSUM)
1721 		__skb_postpush_rcsum(skb, ptr, len, offset);
1722 	if (flags & BPF_F_INVALIDATE_HASH)
1723 		skb_clear_hash(skb);
1724 
1725 	return 0;
1726 }
1727 
1728 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1729 	.func		= bpf_skb_store_bytes,
1730 	.gpl_only	= false,
1731 	.ret_type	= RET_INTEGER,
1732 	.arg1_type	= ARG_PTR_TO_CTX,
1733 	.arg2_type	= ARG_ANYTHING,
1734 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1735 	.arg4_type	= ARG_CONST_SIZE,
1736 	.arg5_type	= ARG_ANYTHING,
1737 };
1738 
__bpf_skb_store_bytes(struct sk_buff * skb,u32 offset,const void * from,u32 len,u64 flags)1739 int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from,
1740 			  u32 len, u64 flags)
1741 {
1742 	return ____bpf_skb_store_bytes(skb, offset, from, len, flags);
1743 }
1744 
BPF_CALL_4(bpf_skb_load_bytes,const struct sk_buff *,skb,u32,offset,void *,to,u32,len)1745 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1746 	   void *, to, u32, len)
1747 {
1748 	void *ptr;
1749 
1750 	if (unlikely(offset > INT_MAX))
1751 		goto err_clear;
1752 
1753 	ptr = skb_header_pointer(skb, offset, len, to);
1754 	if (unlikely(!ptr))
1755 		goto err_clear;
1756 	if (ptr != to)
1757 		memcpy(to, ptr, len);
1758 
1759 	return 0;
1760 err_clear:
1761 	memset(to, 0, len);
1762 	return -EFAULT;
1763 }
1764 
1765 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1766 	.func		= bpf_skb_load_bytes,
1767 	.gpl_only	= false,
1768 	.ret_type	= RET_INTEGER,
1769 	.arg1_type	= ARG_PTR_TO_CTX,
1770 	.arg2_type	= ARG_ANYTHING,
1771 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1772 	.arg4_type	= ARG_CONST_SIZE,
1773 };
1774 
__bpf_skb_load_bytes(const struct sk_buff * skb,u32 offset,void * to,u32 len)1775 int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
1776 {
1777 	return ____bpf_skb_load_bytes(skb, offset, to, len);
1778 }
1779 
BPF_CALL_4(bpf_flow_dissector_load_bytes,const struct bpf_flow_dissector *,ctx,u32,offset,void *,to,u32,len)1780 BPF_CALL_4(bpf_flow_dissector_load_bytes,
1781 	   const struct bpf_flow_dissector *, ctx, u32, offset,
1782 	   void *, to, u32, len)
1783 {
1784 	void *ptr;
1785 
1786 	if (unlikely(offset > 0xffff))
1787 		goto err_clear;
1788 
1789 	if (unlikely(!ctx->skb))
1790 		goto err_clear;
1791 
1792 	ptr = skb_header_pointer(ctx->skb, offset, len, to);
1793 	if (unlikely(!ptr))
1794 		goto err_clear;
1795 	if (ptr != to)
1796 		memcpy(to, ptr, len);
1797 
1798 	return 0;
1799 err_clear:
1800 	memset(to, 0, len);
1801 	return -EFAULT;
1802 }
1803 
1804 static const struct bpf_func_proto bpf_flow_dissector_load_bytes_proto = {
1805 	.func		= bpf_flow_dissector_load_bytes,
1806 	.gpl_only	= false,
1807 	.ret_type	= RET_INTEGER,
1808 	.arg1_type	= ARG_PTR_TO_CTX,
1809 	.arg2_type	= ARG_ANYTHING,
1810 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1811 	.arg4_type	= ARG_CONST_SIZE,
1812 };
1813 
BPF_CALL_5(bpf_skb_load_bytes_relative,const struct sk_buff *,skb,u32,offset,void *,to,u32,len,u32,start_header)1814 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
1815 	   u32, offset, void *, to, u32, len, u32, start_header)
1816 {
1817 	u8 *end = skb_tail_pointer(skb);
1818 	u8 *start, *ptr;
1819 
1820 	if (unlikely(offset > 0xffff))
1821 		goto err_clear;
1822 
1823 	switch (start_header) {
1824 	case BPF_HDR_START_MAC:
1825 		if (unlikely(!skb_mac_header_was_set(skb)))
1826 			goto err_clear;
1827 		start = skb_mac_header(skb);
1828 		break;
1829 	case BPF_HDR_START_NET:
1830 		start = skb_network_header(skb);
1831 		break;
1832 	default:
1833 		goto err_clear;
1834 	}
1835 
1836 	ptr = start + offset;
1837 
1838 	if (likely(ptr + len <= end)) {
1839 		memcpy(to, ptr, len);
1840 		return 0;
1841 	}
1842 
1843 err_clear:
1844 	memset(to, 0, len);
1845 	return -EFAULT;
1846 }
1847 
1848 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
1849 	.func		= bpf_skb_load_bytes_relative,
1850 	.gpl_only	= false,
1851 	.ret_type	= RET_INTEGER,
1852 	.arg1_type	= ARG_PTR_TO_CTX,
1853 	.arg2_type	= ARG_ANYTHING,
1854 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1855 	.arg4_type	= ARG_CONST_SIZE,
1856 	.arg5_type	= ARG_ANYTHING,
1857 };
1858 
BPF_CALL_2(bpf_skb_pull_data,struct sk_buff *,skb,u32,len)1859 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1860 {
1861 	/* Idea is the following: should the needed direct read/write
1862 	 * test fail during runtime, we can pull in more data and redo
1863 	 * again, since implicitly, we invalidate previous checks here.
1864 	 *
1865 	 * Or, since we know how much we need to make read/writeable,
1866 	 * this can be done once at the program beginning for direct
1867 	 * access case. By this we overcome limitations of only current
1868 	 * headroom being accessible.
1869 	 */
1870 	return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1871 }
1872 
1873 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1874 	.func		= bpf_skb_pull_data,
1875 	.gpl_only	= false,
1876 	.ret_type	= RET_INTEGER,
1877 	.arg1_type	= ARG_PTR_TO_CTX,
1878 	.arg2_type	= ARG_ANYTHING,
1879 };
1880 
BPF_CALL_1(bpf_sk_fullsock,struct sock *,sk)1881 BPF_CALL_1(bpf_sk_fullsock, struct sock *, sk)
1882 {
1883 	return sk_fullsock(sk) ? (unsigned long)sk : (unsigned long)NULL;
1884 }
1885 
1886 static const struct bpf_func_proto bpf_sk_fullsock_proto = {
1887 	.func		= bpf_sk_fullsock,
1888 	.gpl_only	= false,
1889 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
1890 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
1891 };
1892 
sk_skb_try_make_writable(struct sk_buff * skb,unsigned int write_len)1893 static inline int sk_skb_try_make_writable(struct sk_buff *skb,
1894 					   unsigned int write_len)
1895 {
1896 	return __bpf_try_make_writable(skb, write_len);
1897 }
1898 
BPF_CALL_2(sk_skb_pull_data,struct sk_buff *,skb,u32,len)1899 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
1900 {
1901 	/* Idea is the following: should the needed direct read/write
1902 	 * test fail during runtime, we can pull in more data and redo
1903 	 * again, since implicitly, we invalidate previous checks here.
1904 	 *
1905 	 * Or, since we know how much we need to make read/writeable,
1906 	 * this can be done once at the program beginning for direct
1907 	 * access case. By this we overcome limitations of only current
1908 	 * headroom being accessible.
1909 	 */
1910 	return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
1911 }
1912 
1913 static const struct bpf_func_proto sk_skb_pull_data_proto = {
1914 	.func		= sk_skb_pull_data,
1915 	.gpl_only	= false,
1916 	.ret_type	= RET_INTEGER,
1917 	.arg1_type	= ARG_PTR_TO_CTX,
1918 	.arg2_type	= ARG_ANYTHING,
1919 };
1920 
BPF_CALL_5(bpf_l3_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1921 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1922 	   u64, from, u64, to, u64, flags)
1923 {
1924 	__sum16 *ptr;
1925 
1926 	if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1927 		return -EINVAL;
1928 	if (unlikely(offset > 0xffff || offset & 1))
1929 		return -EFAULT;
1930 	if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1931 		return -EFAULT;
1932 
1933 	ptr = (__sum16 *)(skb->data + offset);
1934 	switch (flags & BPF_F_HDR_FIELD_MASK) {
1935 	case 0:
1936 		if (unlikely(from != 0))
1937 			return -EINVAL;
1938 
1939 		csum_replace_by_diff(ptr, to);
1940 		break;
1941 	case 2:
1942 		csum_replace2(ptr, from, to);
1943 		break;
1944 	case 4:
1945 		csum_replace4(ptr, from, to);
1946 		break;
1947 	default:
1948 		return -EINVAL;
1949 	}
1950 
1951 	return 0;
1952 }
1953 
1954 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1955 	.func		= bpf_l3_csum_replace,
1956 	.gpl_only	= false,
1957 	.ret_type	= RET_INTEGER,
1958 	.arg1_type	= ARG_PTR_TO_CTX,
1959 	.arg2_type	= ARG_ANYTHING,
1960 	.arg3_type	= ARG_ANYTHING,
1961 	.arg4_type	= ARG_ANYTHING,
1962 	.arg5_type	= ARG_ANYTHING,
1963 };
1964 
BPF_CALL_5(bpf_l4_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1965 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1966 	   u64, from, u64, to, u64, flags)
1967 {
1968 	bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1969 	bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1970 	bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1971 	__sum16 *ptr;
1972 
1973 	if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1974 			       BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1975 		return -EINVAL;
1976 	if (unlikely(offset > 0xffff || offset & 1))
1977 		return -EFAULT;
1978 	if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1979 		return -EFAULT;
1980 
1981 	ptr = (__sum16 *)(skb->data + offset);
1982 	if (is_mmzero && !do_mforce && !*ptr)
1983 		return 0;
1984 
1985 	switch (flags & BPF_F_HDR_FIELD_MASK) {
1986 	case 0:
1987 		if (unlikely(from != 0))
1988 			return -EINVAL;
1989 
1990 		inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1991 		break;
1992 	case 2:
1993 		inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1994 		break;
1995 	case 4:
1996 		inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1997 		break;
1998 	default:
1999 		return -EINVAL;
2000 	}
2001 
2002 	if (is_mmzero && !*ptr)
2003 		*ptr = CSUM_MANGLED_0;
2004 	return 0;
2005 }
2006 
2007 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
2008 	.func		= bpf_l4_csum_replace,
2009 	.gpl_only	= false,
2010 	.ret_type	= RET_INTEGER,
2011 	.arg1_type	= ARG_PTR_TO_CTX,
2012 	.arg2_type	= ARG_ANYTHING,
2013 	.arg3_type	= ARG_ANYTHING,
2014 	.arg4_type	= ARG_ANYTHING,
2015 	.arg5_type	= ARG_ANYTHING,
2016 };
2017 
BPF_CALL_5(bpf_csum_diff,__be32 *,from,u32,from_size,__be32 *,to,u32,to_size,__wsum,seed)2018 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
2019 	   __be32 *, to, u32, to_size, __wsum, seed)
2020 {
2021 	struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
2022 	u32 diff_size = from_size + to_size;
2023 	int i, j = 0;
2024 
2025 	/* This is quite flexible, some examples:
2026 	 *
2027 	 * from_size == 0, to_size > 0,  seed := csum --> pushing data
2028 	 * from_size > 0,  to_size == 0, seed := csum --> pulling data
2029 	 * from_size > 0,  to_size > 0,  seed := 0    --> diffing data
2030 	 *
2031 	 * Even for diffing, from_size and to_size don't need to be equal.
2032 	 */
2033 	if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
2034 		     diff_size > sizeof(sp->diff)))
2035 		return -EINVAL;
2036 
2037 	for (i = 0; i < from_size / sizeof(__be32); i++, j++)
2038 		sp->diff[j] = ~from[i];
2039 	for (i = 0; i <   to_size / sizeof(__be32); i++, j++)
2040 		sp->diff[j] = to[i];
2041 
2042 	return csum_partial(sp->diff, diff_size, seed);
2043 }
2044 
2045 static const struct bpf_func_proto bpf_csum_diff_proto = {
2046 	.func		= bpf_csum_diff,
2047 	.gpl_only	= false,
2048 	.pkt_access	= true,
2049 	.ret_type	= RET_INTEGER,
2050 	.arg1_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2051 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
2052 	.arg3_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2053 	.arg4_type	= ARG_CONST_SIZE_OR_ZERO,
2054 	.arg5_type	= ARG_ANYTHING,
2055 };
2056 
BPF_CALL_2(bpf_csum_update,struct sk_buff *,skb,__wsum,csum)2057 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
2058 {
2059 	/* The interface is to be used in combination with bpf_csum_diff()
2060 	 * for direct packet writes. csum rotation for alignment as well
2061 	 * as emulating csum_sub() can be done from the eBPF program.
2062 	 */
2063 	if (skb->ip_summed == CHECKSUM_COMPLETE)
2064 		return (skb->csum = csum_add(skb->csum, csum));
2065 
2066 	return -ENOTSUPP;
2067 }
2068 
2069 static const struct bpf_func_proto bpf_csum_update_proto = {
2070 	.func		= bpf_csum_update,
2071 	.gpl_only	= false,
2072 	.ret_type	= RET_INTEGER,
2073 	.arg1_type	= ARG_PTR_TO_CTX,
2074 	.arg2_type	= ARG_ANYTHING,
2075 };
2076 
BPF_CALL_2(bpf_csum_level,struct sk_buff *,skb,u64,level)2077 BPF_CALL_2(bpf_csum_level, struct sk_buff *, skb, u64, level)
2078 {
2079 	/* The interface is to be used in combination with bpf_skb_adjust_room()
2080 	 * for encap/decap of packet headers when BPF_F_ADJ_ROOM_NO_CSUM_RESET
2081 	 * is passed as flags, for example.
2082 	 */
2083 	switch (level) {
2084 	case BPF_CSUM_LEVEL_INC:
2085 		__skb_incr_checksum_unnecessary(skb);
2086 		break;
2087 	case BPF_CSUM_LEVEL_DEC:
2088 		__skb_decr_checksum_unnecessary(skb);
2089 		break;
2090 	case BPF_CSUM_LEVEL_RESET:
2091 		__skb_reset_checksum_unnecessary(skb);
2092 		break;
2093 	case BPF_CSUM_LEVEL_QUERY:
2094 		return skb->ip_summed == CHECKSUM_UNNECESSARY ?
2095 		       skb->csum_level : -EACCES;
2096 	default:
2097 		return -EINVAL;
2098 	}
2099 
2100 	return 0;
2101 }
2102 
2103 static const struct bpf_func_proto bpf_csum_level_proto = {
2104 	.func		= bpf_csum_level,
2105 	.gpl_only	= false,
2106 	.ret_type	= RET_INTEGER,
2107 	.arg1_type	= ARG_PTR_TO_CTX,
2108 	.arg2_type	= ARG_ANYTHING,
2109 };
2110 
__bpf_rx_skb(struct net_device * dev,struct sk_buff * skb)2111 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
2112 {
2113 	return dev_forward_skb_nomtu(dev, skb);
2114 }
2115 
__bpf_rx_skb_no_mac(struct net_device * dev,struct sk_buff * skb)2116 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
2117 				      struct sk_buff *skb)
2118 {
2119 	int ret = ____dev_forward_skb(dev, skb, false);
2120 
2121 	if (likely(!ret)) {
2122 		skb->dev = dev;
2123 		ret = netif_rx(skb);
2124 	}
2125 
2126 	return ret;
2127 }
2128 
__bpf_tx_skb(struct net_device * dev,struct sk_buff * skb)2129 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
2130 {
2131 	int ret;
2132 
2133 	if (dev_xmit_recursion()) {
2134 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2135 		kfree_skb(skb);
2136 		return -ENETDOWN;
2137 	}
2138 
2139 	skb->dev = dev;
2140 	skb_set_redirected_noclear(skb, skb_at_tc_ingress(skb));
2141 	skb_clear_tstamp(skb);
2142 
2143 	dev_xmit_recursion_inc();
2144 	ret = dev_queue_xmit(skb);
2145 	dev_xmit_recursion_dec();
2146 
2147 	return ret;
2148 }
2149 
__bpf_redirect_no_mac(struct sk_buff * skb,struct net_device * dev,u32 flags)2150 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
2151 				 u32 flags)
2152 {
2153 	unsigned int mlen = skb_network_offset(skb);
2154 
2155 	if (unlikely(skb->len <= mlen)) {
2156 		kfree_skb(skb);
2157 		return -ERANGE;
2158 	}
2159 
2160 	if (mlen) {
2161 		__skb_pull(skb, mlen);
2162 
2163 		/* At ingress, the mac header has already been pulled once.
2164 		 * At egress, skb_pospull_rcsum has to be done in case that
2165 		 * the skb is originated from ingress (i.e. a forwarded skb)
2166 		 * to ensure that rcsum starts at net header.
2167 		 */
2168 		if (!skb_at_tc_ingress(skb))
2169 			skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
2170 	}
2171 	skb_pop_mac_header(skb);
2172 	skb_reset_mac_len(skb);
2173 	return flags & BPF_F_INGRESS ?
2174 	       __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
2175 }
2176 
__bpf_redirect_common(struct sk_buff * skb,struct net_device * dev,u32 flags)2177 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
2178 				 u32 flags)
2179 {
2180 	/* Verify that a link layer header is carried */
2181 	if (unlikely(skb->mac_header >= skb->network_header || skb->len == 0)) {
2182 		kfree_skb(skb);
2183 		return -ERANGE;
2184 	}
2185 
2186 	bpf_push_mac_rcsum(skb);
2187 	return flags & BPF_F_INGRESS ?
2188 	       __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
2189 }
2190 
__bpf_redirect(struct sk_buff * skb,struct net_device * dev,u32 flags)2191 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
2192 			  u32 flags)
2193 {
2194 	if (dev_is_mac_header_xmit(dev))
2195 		return __bpf_redirect_common(skb, dev, flags);
2196 	else
2197 		return __bpf_redirect_no_mac(skb, dev, flags);
2198 }
2199 
2200 #if IS_ENABLED(CONFIG_IPV6)
bpf_out_neigh_v6(struct net * net,struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2201 static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
2202 			    struct net_device *dev, struct bpf_nh_params *nh)
2203 {
2204 	u32 hh_len = LL_RESERVED_SPACE(dev);
2205 	const struct in6_addr *nexthop;
2206 	struct dst_entry *dst = NULL;
2207 	struct neighbour *neigh;
2208 
2209 	if (dev_xmit_recursion()) {
2210 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2211 		goto out_drop;
2212 	}
2213 
2214 	skb->dev = dev;
2215 	skb_clear_tstamp(skb);
2216 
2217 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2218 		skb = skb_expand_head(skb, hh_len);
2219 		if (!skb)
2220 			return -ENOMEM;
2221 	}
2222 
2223 	rcu_read_lock();
2224 	if (!nh) {
2225 		dst = skb_dst(skb);
2226 		nexthop = rt6_nexthop(dst_rt6_info(dst),
2227 				      &ipv6_hdr(skb)->daddr);
2228 	} else {
2229 		nexthop = &nh->ipv6_nh;
2230 	}
2231 	neigh = ip_neigh_gw6(dev, nexthop);
2232 	if (likely(!IS_ERR(neigh))) {
2233 		int ret;
2234 
2235 		sock_confirm_neigh(skb, neigh);
2236 		local_bh_disable();
2237 		dev_xmit_recursion_inc();
2238 		ret = neigh_output(neigh, skb, false);
2239 		dev_xmit_recursion_dec();
2240 		local_bh_enable();
2241 		rcu_read_unlock();
2242 		return ret;
2243 	}
2244 	rcu_read_unlock();
2245 	if (dst)
2246 		IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
2247 out_drop:
2248 	kfree_skb(skb);
2249 	return -ENETDOWN;
2250 }
2251 
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2252 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2253 				   struct bpf_nh_params *nh)
2254 {
2255 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
2256 	struct net *net = dev_net(dev);
2257 	int err, ret = NET_XMIT_DROP;
2258 
2259 	if (!nh) {
2260 		struct dst_entry *dst;
2261 		struct flowi6 fl6 = {
2262 			.flowi6_flags = FLOWI_FLAG_ANYSRC,
2263 			.flowi6_mark  = skb->mark,
2264 			.flowlabel    = ip6_flowinfo(ip6h),
2265 			.flowi6_oif   = dev->ifindex,
2266 			.flowi6_proto = ip6h->nexthdr,
2267 			.daddr	      = ip6h->daddr,
2268 			.saddr	      = ip6h->saddr,
2269 		};
2270 
2271 		dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &fl6, NULL);
2272 		if (IS_ERR(dst))
2273 			goto out_drop;
2274 
2275 		skb_dst_set(skb, dst);
2276 	} else if (nh->nh_family != AF_INET6) {
2277 		goto out_drop;
2278 	}
2279 
2280 	err = bpf_out_neigh_v6(net, skb, dev, nh);
2281 	if (unlikely(net_xmit_eval(err)))
2282 		DEV_STATS_INC(dev, tx_errors);
2283 	else
2284 		ret = NET_XMIT_SUCCESS;
2285 	goto out_xmit;
2286 out_drop:
2287 	DEV_STATS_INC(dev, tx_errors);
2288 	kfree_skb(skb);
2289 out_xmit:
2290 	return ret;
2291 }
2292 #else
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2293 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2294 				   struct bpf_nh_params *nh)
2295 {
2296 	kfree_skb(skb);
2297 	return NET_XMIT_DROP;
2298 }
2299 #endif /* CONFIG_IPV6 */
2300 
2301 #if IS_ENABLED(CONFIG_INET)
bpf_out_neigh_v4(struct net * net,struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2302 static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
2303 			    struct net_device *dev, struct bpf_nh_params *nh)
2304 {
2305 	u32 hh_len = LL_RESERVED_SPACE(dev);
2306 	struct neighbour *neigh;
2307 	bool is_v6gw = false;
2308 
2309 	if (dev_xmit_recursion()) {
2310 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2311 		goto out_drop;
2312 	}
2313 
2314 	skb->dev = dev;
2315 	skb_clear_tstamp(skb);
2316 
2317 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2318 		skb = skb_expand_head(skb, hh_len);
2319 		if (!skb)
2320 			return -ENOMEM;
2321 	}
2322 
2323 	rcu_read_lock();
2324 	if (!nh) {
2325 		struct dst_entry *dst = skb_dst(skb);
2326 		struct rtable *rt = container_of(dst, struct rtable, dst);
2327 
2328 		neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
2329 	} else if (nh->nh_family == AF_INET6) {
2330 		neigh = ip_neigh_gw6(dev, &nh->ipv6_nh);
2331 		is_v6gw = true;
2332 	} else if (nh->nh_family == AF_INET) {
2333 		neigh = ip_neigh_gw4(dev, nh->ipv4_nh);
2334 	} else {
2335 		rcu_read_unlock();
2336 		goto out_drop;
2337 	}
2338 
2339 	if (likely(!IS_ERR(neigh))) {
2340 		int ret;
2341 
2342 		sock_confirm_neigh(skb, neigh);
2343 		local_bh_disable();
2344 		dev_xmit_recursion_inc();
2345 		ret = neigh_output(neigh, skb, is_v6gw);
2346 		dev_xmit_recursion_dec();
2347 		local_bh_enable();
2348 		rcu_read_unlock();
2349 		return ret;
2350 	}
2351 	rcu_read_unlock();
2352 out_drop:
2353 	kfree_skb(skb);
2354 	return -ENETDOWN;
2355 }
2356 
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2357 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2358 				   struct bpf_nh_params *nh)
2359 {
2360 	const struct iphdr *ip4h = ip_hdr(skb);
2361 	struct net *net = dev_net(dev);
2362 	int err, ret = NET_XMIT_DROP;
2363 
2364 	if (!nh) {
2365 		struct flowi4 fl4 = {
2366 			.flowi4_flags = FLOWI_FLAG_ANYSRC,
2367 			.flowi4_mark  = skb->mark,
2368 			.flowi4_tos   = RT_TOS(ip4h->tos),
2369 			.flowi4_oif   = dev->ifindex,
2370 			.flowi4_proto = ip4h->protocol,
2371 			.daddr	      = ip4h->daddr,
2372 			.saddr	      = ip4h->saddr,
2373 		};
2374 		struct rtable *rt;
2375 
2376 		rt = ip_route_output_flow(net, &fl4, NULL);
2377 		if (IS_ERR(rt))
2378 			goto out_drop;
2379 		if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
2380 			ip_rt_put(rt);
2381 			goto out_drop;
2382 		}
2383 
2384 		skb_dst_set(skb, &rt->dst);
2385 	}
2386 
2387 	err = bpf_out_neigh_v4(net, skb, dev, nh);
2388 	if (unlikely(net_xmit_eval(err)))
2389 		DEV_STATS_INC(dev, tx_errors);
2390 	else
2391 		ret = NET_XMIT_SUCCESS;
2392 	goto out_xmit;
2393 out_drop:
2394 	DEV_STATS_INC(dev, tx_errors);
2395 	kfree_skb(skb);
2396 out_xmit:
2397 	return ret;
2398 }
2399 #else
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2400 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2401 				   struct bpf_nh_params *nh)
2402 {
2403 	kfree_skb(skb);
2404 	return NET_XMIT_DROP;
2405 }
2406 #endif /* CONFIG_INET */
2407 
__bpf_redirect_neigh(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2408 static int __bpf_redirect_neigh(struct sk_buff *skb, struct net_device *dev,
2409 				struct bpf_nh_params *nh)
2410 {
2411 	struct ethhdr *ethh = eth_hdr(skb);
2412 
2413 	if (unlikely(skb->mac_header >= skb->network_header))
2414 		goto out;
2415 	bpf_push_mac_rcsum(skb);
2416 	if (is_multicast_ether_addr(ethh->h_dest))
2417 		goto out;
2418 
2419 	skb_pull(skb, sizeof(*ethh));
2420 	skb_unset_mac_header(skb);
2421 	skb_reset_network_header(skb);
2422 
2423 	if (skb->protocol == htons(ETH_P_IP))
2424 		return __bpf_redirect_neigh_v4(skb, dev, nh);
2425 	else if (skb->protocol == htons(ETH_P_IPV6))
2426 		return __bpf_redirect_neigh_v6(skb, dev, nh);
2427 out:
2428 	kfree_skb(skb);
2429 	return -ENOTSUPP;
2430 }
2431 
2432 /* Internal, non-exposed redirect flags. */
2433 enum {
2434 	BPF_F_NEIGH	= (1ULL << 16),
2435 	BPF_F_PEER	= (1ULL << 17),
2436 	BPF_F_NEXTHOP	= (1ULL << 18),
2437 #define BPF_F_REDIRECT_INTERNAL	(BPF_F_NEIGH | BPF_F_PEER | BPF_F_NEXTHOP)
2438 };
2439 
BPF_CALL_3(bpf_clone_redirect,struct sk_buff *,skb,u32,ifindex,u64,flags)2440 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
2441 {
2442 	struct net_device *dev;
2443 	struct sk_buff *clone;
2444 	int ret;
2445 
2446 	BUILD_BUG_ON(BPF_F_REDIRECT_INTERNAL & BPF_F_REDIRECT_FLAGS);
2447 
2448 	if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2449 		return -EINVAL;
2450 
2451 	dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
2452 	if (unlikely(!dev))
2453 		return -EINVAL;
2454 
2455 	clone = skb_clone(skb, GFP_ATOMIC);
2456 	if (unlikely(!clone))
2457 		return -ENOMEM;
2458 
2459 	/* For direct write, we need to keep the invariant that the skbs
2460 	 * we're dealing with need to be uncloned. Should uncloning fail
2461 	 * here, we need to free the just generated clone to unclone once
2462 	 * again.
2463 	 */
2464 	ret = bpf_try_make_head_writable(skb);
2465 	if (unlikely(ret)) {
2466 		kfree_skb(clone);
2467 		return -ENOMEM;
2468 	}
2469 
2470 	return __bpf_redirect(clone, dev, flags);
2471 }
2472 
2473 static const struct bpf_func_proto bpf_clone_redirect_proto = {
2474 	.func           = bpf_clone_redirect,
2475 	.gpl_only       = false,
2476 	.ret_type       = RET_INTEGER,
2477 	.arg1_type      = ARG_PTR_TO_CTX,
2478 	.arg2_type      = ARG_ANYTHING,
2479 	.arg3_type      = ARG_ANYTHING,
2480 };
2481 
2482 DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
2483 EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info);
2484 
skb_do_redirect(struct sk_buff * skb)2485 int skb_do_redirect(struct sk_buff *skb)
2486 {
2487 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2488 	struct net *net = dev_net(skb->dev);
2489 	struct net_device *dev;
2490 	u32 flags = ri->flags;
2491 
2492 	dev = dev_get_by_index_rcu(net, ri->tgt_index);
2493 	ri->tgt_index = 0;
2494 	ri->flags = 0;
2495 	if (unlikely(!dev))
2496 		goto out_drop;
2497 	if (flags & BPF_F_PEER) {
2498 		const struct net_device_ops *ops = dev->netdev_ops;
2499 
2500 		if (unlikely(!ops->ndo_get_peer_dev ||
2501 			     !skb_at_tc_ingress(skb)))
2502 			goto out_drop;
2503 		dev = ops->ndo_get_peer_dev(dev);
2504 		if (unlikely(!dev ||
2505 			     !(dev->flags & IFF_UP) ||
2506 			     net_eq(net, dev_net(dev))))
2507 			goto out_drop;
2508 		skb->dev = dev;
2509 		dev_sw_netstats_rx_add(dev, skb->len);
2510 		skb_scrub_packet(skb, false);
2511 		return -EAGAIN;
2512 	}
2513 	return flags & BPF_F_NEIGH ?
2514 	       __bpf_redirect_neigh(skb, dev, flags & BPF_F_NEXTHOP ?
2515 				    &ri->nh : NULL) :
2516 	       __bpf_redirect(skb, dev, flags);
2517 out_drop:
2518 	kfree_skb(skb);
2519 	return -EINVAL;
2520 }
2521 
BPF_CALL_2(bpf_redirect,u32,ifindex,u64,flags)2522 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
2523 {
2524 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2525 
2526 	if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2527 		return TC_ACT_SHOT;
2528 
2529 	ri->flags = flags;
2530 	ri->tgt_index = ifindex;
2531 
2532 	return TC_ACT_REDIRECT;
2533 }
2534 
2535 static const struct bpf_func_proto bpf_redirect_proto = {
2536 	.func           = bpf_redirect,
2537 	.gpl_only       = false,
2538 	.ret_type       = RET_INTEGER,
2539 	.arg1_type      = ARG_ANYTHING,
2540 	.arg2_type      = ARG_ANYTHING,
2541 };
2542 
BPF_CALL_2(bpf_redirect_peer,u32,ifindex,u64,flags)2543 BPF_CALL_2(bpf_redirect_peer, u32, ifindex, u64, flags)
2544 {
2545 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2546 
2547 	if (unlikely(flags))
2548 		return TC_ACT_SHOT;
2549 
2550 	ri->flags = BPF_F_PEER;
2551 	ri->tgt_index = ifindex;
2552 
2553 	return TC_ACT_REDIRECT;
2554 }
2555 
2556 static const struct bpf_func_proto bpf_redirect_peer_proto = {
2557 	.func           = bpf_redirect_peer,
2558 	.gpl_only       = false,
2559 	.ret_type       = RET_INTEGER,
2560 	.arg1_type      = ARG_ANYTHING,
2561 	.arg2_type      = ARG_ANYTHING,
2562 };
2563 
BPF_CALL_4(bpf_redirect_neigh,u32,ifindex,struct bpf_redir_neigh *,params,int,plen,u64,flags)2564 BPF_CALL_4(bpf_redirect_neigh, u32, ifindex, struct bpf_redir_neigh *, params,
2565 	   int, plen, u64, flags)
2566 {
2567 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2568 
2569 	if (unlikely((plen && plen < sizeof(*params)) || flags))
2570 		return TC_ACT_SHOT;
2571 
2572 	ri->flags = BPF_F_NEIGH | (plen ? BPF_F_NEXTHOP : 0);
2573 	ri->tgt_index = ifindex;
2574 
2575 	BUILD_BUG_ON(sizeof(struct bpf_redir_neigh) != sizeof(struct bpf_nh_params));
2576 	if (plen)
2577 		memcpy(&ri->nh, params, sizeof(ri->nh));
2578 
2579 	return TC_ACT_REDIRECT;
2580 }
2581 
2582 static const struct bpf_func_proto bpf_redirect_neigh_proto = {
2583 	.func		= bpf_redirect_neigh,
2584 	.gpl_only	= false,
2585 	.ret_type	= RET_INTEGER,
2586 	.arg1_type	= ARG_ANYTHING,
2587 	.arg2_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2588 	.arg3_type      = ARG_CONST_SIZE_OR_ZERO,
2589 	.arg4_type	= ARG_ANYTHING,
2590 };
2591 
BPF_CALL_2(bpf_msg_apply_bytes,struct sk_msg *,msg,u32,bytes)2592 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes)
2593 {
2594 	msg->apply_bytes = bytes;
2595 	return 0;
2596 }
2597 
2598 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
2599 	.func           = bpf_msg_apply_bytes,
2600 	.gpl_only       = false,
2601 	.ret_type       = RET_INTEGER,
2602 	.arg1_type	= ARG_PTR_TO_CTX,
2603 	.arg2_type      = ARG_ANYTHING,
2604 };
2605 
BPF_CALL_2(bpf_msg_cork_bytes,struct sk_msg *,msg,u32,bytes)2606 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
2607 {
2608 	msg->cork_bytes = bytes;
2609 	return 0;
2610 }
2611 
sk_msg_reset_curr(struct sk_msg * msg)2612 static void sk_msg_reset_curr(struct sk_msg *msg)
2613 {
2614 	if (!msg->sg.size) {
2615 		msg->sg.curr = msg->sg.start;
2616 		msg->sg.copybreak = 0;
2617 	} else {
2618 		u32 i = msg->sg.end;
2619 
2620 		sk_msg_iter_var_prev(i);
2621 		msg->sg.curr = i;
2622 		msg->sg.copybreak = msg->sg.data[i].length;
2623 	}
2624 }
2625 
2626 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
2627 	.func           = bpf_msg_cork_bytes,
2628 	.gpl_only       = false,
2629 	.ret_type       = RET_INTEGER,
2630 	.arg1_type	= ARG_PTR_TO_CTX,
2631 	.arg2_type      = ARG_ANYTHING,
2632 };
2633 
BPF_CALL_4(bpf_msg_pull_data,struct sk_msg *,msg,u32,start,u32,end,u64,flags)2634 BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
2635 	   u32, end, u64, flags)
2636 {
2637 	u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start;
2638 	u32 first_sge, last_sge, i, shift, bytes_sg_total;
2639 	struct scatterlist *sge;
2640 	u8 *raw, *to, *from;
2641 	struct page *page;
2642 
2643 	if (unlikely(flags || end <= start))
2644 		return -EINVAL;
2645 
2646 	/* First find the starting scatterlist element */
2647 	i = msg->sg.start;
2648 	do {
2649 		offset += len;
2650 		len = sk_msg_elem(msg, i)->length;
2651 		if (start < offset + len)
2652 			break;
2653 		sk_msg_iter_var_next(i);
2654 	} while (i != msg->sg.end);
2655 
2656 	if (unlikely(start >= offset + len))
2657 		return -EINVAL;
2658 
2659 	first_sge = i;
2660 	/* The start may point into the sg element so we need to also
2661 	 * account for the headroom.
2662 	 */
2663 	bytes_sg_total = start - offset + bytes;
2664 	if (!test_bit(i, msg->sg.copy) && bytes_sg_total <= len)
2665 		goto out;
2666 
2667 	/* At this point we need to linearize multiple scatterlist
2668 	 * elements or a single shared page. Either way we need to
2669 	 * copy into a linear buffer exclusively owned by BPF. Then
2670 	 * place the buffer in the scatterlist and fixup the original
2671 	 * entries by removing the entries now in the linear buffer
2672 	 * and shifting the remaining entries. For now we do not try
2673 	 * to copy partial entries to avoid complexity of running out
2674 	 * of sg_entry slots. The downside is reading a single byte
2675 	 * will copy the entire sg entry.
2676 	 */
2677 	do {
2678 		copy += sk_msg_elem(msg, i)->length;
2679 		sk_msg_iter_var_next(i);
2680 		if (bytes_sg_total <= copy)
2681 			break;
2682 	} while (i != msg->sg.end);
2683 	last_sge = i;
2684 
2685 	if (unlikely(bytes_sg_total > copy))
2686 		return -EINVAL;
2687 
2688 	page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2689 			   get_order(copy));
2690 	if (unlikely(!page))
2691 		return -ENOMEM;
2692 
2693 	raw = page_address(page);
2694 	i = first_sge;
2695 	do {
2696 		sge = sk_msg_elem(msg, i);
2697 		from = sg_virt(sge);
2698 		len = sge->length;
2699 		to = raw + poffset;
2700 
2701 		memcpy(to, from, len);
2702 		poffset += len;
2703 		sge->length = 0;
2704 		put_page(sg_page(sge));
2705 
2706 		sk_msg_iter_var_next(i);
2707 	} while (i != last_sge);
2708 
2709 	sg_set_page(&msg->sg.data[first_sge], page, copy, 0);
2710 
2711 	/* To repair sg ring we need to shift entries. If we only
2712 	 * had a single entry though we can just replace it and
2713 	 * be done. Otherwise walk the ring and shift the entries.
2714 	 */
2715 	WARN_ON_ONCE(last_sge == first_sge);
2716 	shift = last_sge > first_sge ?
2717 		last_sge - first_sge - 1 :
2718 		NR_MSG_FRAG_IDS - first_sge + last_sge - 1;
2719 	if (!shift)
2720 		goto out;
2721 
2722 	i = first_sge;
2723 	sk_msg_iter_var_next(i);
2724 	do {
2725 		u32 move_from;
2726 
2727 		if (i + shift >= NR_MSG_FRAG_IDS)
2728 			move_from = i + shift - NR_MSG_FRAG_IDS;
2729 		else
2730 			move_from = i + shift;
2731 		if (move_from == msg->sg.end)
2732 			break;
2733 
2734 		msg->sg.data[i] = msg->sg.data[move_from];
2735 		msg->sg.data[move_from].length = 0;
2736 		msg->sg.data[move_from].page_link = 0;
2737 		msg->sg.data[move_from].offset = 0;
2738 		sk_msg_iter_var_next(i);
2739 	} while (1);
2740 
2741 	msg->sg.end = msg->sg.end - shift > msg->sg.end ?
2742 		      msg->sg.end - shift + NR_MSG_FRAG_IDS :
2743 		      msg->sg.end - shift;
2744 out:
2745 	sk_msg_reset_curr(msg);
2746 	msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
2747 	msg->data_end = msg->data + bytes;
2748 	return 0;
2749 }
2750 
2751 static const struct bpf_func_proto bpf_msg_pull_data_proto = {
2752 	.func		= bpf_msg_pull_data,
2753 	.gpl_only	= false,
2754 	.ret_type	= RET_INTEGER,
2755 	.arg1_type	= ARG_PTR_TO_CTX,
2756 	.arg2_type	= ARG_ANYTHING,
2757 	.arg3_type	= ARG_ANYTHING,
2758 	.arg4_type	= ARG_ANYTHING,
2759 };
2760 
BPF_CALL_4(bpf_msg_push_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2761 BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
2762 	   u32, len, u64, flags)
2763 {
2764 	struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge;
2765 	u32 new, i = 0, l = 0, space, copy = 0, offset = 0;
2766 	u8 *raw, *to, *from;
2767 	struct page *page;
2768 
2769 	if (unlikely(flags))
2770 		return -EINVAL;
2771 
2772 	if (unlikely(len == 0))
2773 		return 0;
2774 
2775 	/* First find the starting scatterlist element */
2776 	i = msg->sg.start;
2777 	do {
2778 		offset += l;
2779 		l = sk_msg_elem(msg, i)->length;
2780 
2781 		if (start < offset + l)
2782 			break;
2783 		sk_msg_iter_var_next(i);
2784 	} while (i != msg->sg.end);
2785 
2786 	if (start > offset + l)
2787 		return -EINVAL;
2788 
2789 	space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2790 
2791 	/* If no space available will fallback to copy, we need at
2792 	 * least one scatterlist elem available to push data into
2793 	 * when start aligns to the beginning of an element or two
2794 	 * when it falls inside an element. We handle the start equals
2795 	 * offset case because its the common case for inserting a
2796 	 * header.
2797 	 */
2798 	if (!space || (space == 1 && start != offset))
2799 		copy = msg->sg.data[i].length;
2800 
2801 	page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2802 			   get_order(copy + len));
2803 	if (unlikely(!page))
2804 		return -ENOMEM;
2805 
2806 	if (copy) {
2807 		int front, back;
2808 
2809 		raw = page_address(page);
2810 
2811 		if (i == msg->sg.end)
2812 			sk_msg_iter_var_prev(i);
2813 		psge = sk_msg_elem(msg, i);
2814 		front = start - offset;
2815 		back = psge->length - front;
2816 		from = sg_virt(psge);
2817 
2818 		if (front)
2819 			memcpy(raw, from, front);
2820 
2821 		if (back) {
2822 			from += front;
2823 			to = raw + front + len;
2824 
2825 			memcpy(to, from, back);
2826 		}
2827 
2828 		put_page(sg_page(psge));
2829 		new = i;
2830 		goto place_new;
2831 	}
2832 
2833 	if (start - offset) {
2834 		if (i == msg->sg.end)
2835 			sk_msg_iter_var_prev(i);
2836 		psge = sk_msg_elem(msg, i);
2837 		rsge = sk_msg_elem_cpy(msg, i);
2838 
2839 		psge->length = start - offset;
2840 		rsge.length -= psge->length;
2841 		rsge.offset += start;
2842 
2843 		sk_msg_iter_var_next(i);
2844 		sg_unmark_end(psge);
2845 		sg_unmark_end(&rsge);
2846 	}
2847 
2848 	/* Slot(s) to place newly allocated data */
2849 	sk_msg_iter_next(msg, end);
2850 	new = i;
2851 	sk_msg_iter_var_next(i);
2852 
2853 	if (i == msg->sg.end) {
2854 		if (!rsge.length)
2855 			goto place_new;
2856 		sk_msg_iter_next(msg, end);
2857 		goto place_new;
2858 	}
2859 
2860 	/* Shift one or two slots as needed */
2861 	sge = sk_msg_elem_cpy(msg, new);
2862 	sg_unmark_end(&sge);
2863 
2864 	nsge = sk_msg_elem_cpy(msg, i);
2865 	if (rsge.length) {
2866 		sk_msg_iter_var_next(i);
2867 		nnsge = sk_msg_elem_cpy(msg, i);
2868 		sk_msg_iter_next(msg, end);
2869 	}
2870 
2871 	while (i != msg->sg.end) {
2872 		msg->sg.data[i] = sge;
2873 		sge = nsge;
2874 		sk_msg_iter_var_next(i);
2875 		if (rsge.length) {
2876 			nsge = nnsge;
2877 			nnsge = sk_msg_elem_cpy(msg, i);
2878 		} else {
2879 			nsge = sk_msg_elem_cpy(msg, i);
2880 		}
2881 	}
2882 
2883 place_new:
2884 	/* Place newly allocated data buffer */
2885 	sk_mem_charge(msg->sk, len);
2886 	msg->sg.size += len;
2887 	__clear_bit(new, msg->sg.copy);
2888 	sg_set_page(&msg->sg.data[new], page, len + copy, 0);
2889 	if (rsge.length) {
2890 		get_page(sg_page(&rsge));
2891 		sk_msg_iter_var_next(new);
2892 		msg->sg.data[new] = rsge;
2893 	}
2894 
2895 	sk_msg_reset_curr(msg);
2896 	sk_msg_compute_data_pointers(msg);
2897 	return 0;
2898 }
2899 
2900 static const struct bpf_func_proto bpf_msg_push_data_proto = {
2901 	.func		= bpf_msg_push_data,
2902 	.gpl_only	= false,
2903 	.ret_type	= RET_INTEGER,
2904 	.arg1_type	= ARG_PTR_TO_CTX,
2905 	.arg2_type	= ARG_ANYTHING,
2906 	.arg3_type	= ARG_ANYTHING,
2907 	.arg4_type	= ARG_ANYTHING,
2908 };
2909 
sk_msg_shift_left(struct sk_msg * msg,int i)2910 static void sk_msg_shift_left(struct sk_msg *msg, int i)
2911 {
2912 	struct scatterlist *sge = sk_msg_elem(msg, i);
2913 	int prev;
2914 
2915 	put_page(sg_page(sge));
2916 	do {
2917 		prev = i;
2918 		sk_msg_iter_var_next(i);
2919 		msg->sg.data[prev] = msg->sg.data[i];
2920 	} while (i != msg->sg.end);
2921 
2922 	sk_msg_iter_prev(msg, end);
2923 }
2924 
sk_msg_shift_right(struct sk_msg * msg,int i)2925 static void sk_msg_shift_right(struct sk_msg *msg, int i)
2926 {
2927 	struct scatterlist tmp, sge;
2928 
2929 	sk_msg_iter_next(msg, end);
2930 	sge = sk_msg_elem_cpy(msg, i);
2931 	sk_msg_iter_var_next(i);
2932 	tmp = sk_msg_elem_cpy(msg, i);
2933 
2934 	while (i != msg->sg.end) {
2935 		msg->sg.data[i] = sge;
2936 		sk_msg_iter_var_next(i);
2937 		sge = tmp;
2938 		tmp = sk_msg_elem_cpy(msg, i);
2939 	}
2940 }
2941 
BPF_CALL_4(bpf_msg_pop_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2942 BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
2943 	   u32, len, u64, flags)
2944 {
2945 	u32 i = 0, l = 0, space, offset = 0;
2946 	u64 last = start + len;
2947 	int pop;
2948 
2949 	if (unlikely(flags))
2950 		return -EINVAL;
2951 
2952 	if (unlikely(len == 0))
2953 		return 0;
2954 
2955 	/* First find the starting scatterlist element */
2956 	i = msg->sg.start;
2957 	do {
2958 		offset += l;
2959 		l = sk_msg_elem(msg, i)->length;
2960 
2961 		if (start < offset + l)
2962 			break;
2963 		sk_msg_iter_var_next(i);
2964 	} while (i != msg->sg.end);
2965 
2966 	/* Bounds checks: start and pop must be inside message */
2967 	if (start >= offset + l || last > msg->sg.size)
2968 		return -EINVAL;
2969 
2970 	space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2971 
2972 	pop = len;
2973 	/* --------------| offset
2974 	 * -| start      |-------- len -------|
2975 	 *
2976 	 *  |----- a ----|-------- pop -------|----- b ----|
2977 	 *  |______________________________________________| length
2978 	 *
2979 	 *
2980 	 * a:   region at front of scatter element to save
2981 	 * b:   region at back of scatter element to save when length > A + pop
2982 	 * pop: region to pop from element, same as input 'pop' here will be
2983 	 *      decremented below per iteration.
2984 	 *
2985 	 * Two top-level cases to handle when start != offset, first B is non
2986 	 * zero and second B is zero corresponding to when a pop includes more
2987 	 * than one element.
2988 	 *
2989 	 * Then if B is non-zero AND there is no space allocate space and
2990 	 * compact A, B regions into page. If there is space shift ring to
2991 	 * the rigth free'ing the next element in ring to place B, leaving
2992 	 * A untouched except to reduce length.
2993 	 */
2994 	if (start != offset) {
2995 		struct scatterlist *nsge, *sge = sk_msg_elem(msg, i);
2996 		int a = start - offset;
2997 		int b = sge->length - pop - a;
2998 
2999 		sk_msg_iter_var_next(i);
3000 
3001 		if (b > 0) {
3002 			if (space) {
3003 				sge->length = a;
3004 				sk_msg_shift_right(msg, i);
3005 				nsge = sk_msg_elem(msg, i);
3006 				get_page(sg_page(sge));
3007 				sg_set_page(nsge,
3008 					    sg_page(sge),
3009 					    b, sge->offset + pop + a);
3010 			} else {
3011 				struct page *page, *orig;
3012 				u8 *to, *from;
3013 
3014 				page = alloc_pages(__GFP_NOWARN |
3015 						   __GFP_COMP   | GFP_ATOMIC,
3016 						   get_order(a + b));
3017 				if (unlikely(!page))
3018 					return -ENOMEM;
3019 
3020 				orig = sg_page(sge);
3021 				from = sg_virt(sge);
3022 				to = page_address(page);
3023 				memcpy(to, from, a);
3024 				memcpy(to + a, from + a + pop, b);
3025 				sg_set_page(sge, page, a + b, 0);
3026 				put_page(orig);
3027 			}
3028 			pop = 0;
3029 		} else {
3030 			pop -= (sge->length - a);
3031 			sge->length = a;
3032 		}
3033 	}
3034 
3035 	/* From above the current layout _must_ be as follows,
3036 	 *
3037 	 * -| offset
3038 	 * -| start
3039 	 *
3040 	 *  |---- pop ---|---------------- b ------------|
3041 	 *  |____________________________________________| length
3042 	 *
3043 	 * Offset and start of the current msg elem are equal because in the
3044 	 * previous case we handled offset != start and either consumed the
3045 	 * entire element and advanced to the next element OR pop == 0.
3046 	 *
3047 	 * Two cases to handle here are first pop is less than the length
3048 	 * leaving some remainder b above. Simply adjust the element's layout
3049 	 * in this case. Or pop >= length of the element so that b = 0. In this
3050 	 * case advance to next element decrementing pop.
3051 	 */
3052 	while (pop) {
3053 		struct scatterlist *sge = sk_msg_elem(msg, i);
3054 
3055 		if (pop < sge->length) {
3056 			sge->length -= pop;
3057 			sge->offset += pop;
3058 			pop = 0;
3059 		} else {
3060 			pop -= sge->length;
3061 			sk_msg_shift_left(msg, i);
3062 		}
3063 	}
3064 
3065 	sk_mem_uncharge(msg->sk, len - pop);
3066 	msg->sg.size -= (len - pop);
3067 	sk_msg_reset_curr(msg);
3068 	sk_msg_compute_data_pointers(msg);
3069 	return 0;
3070 }
3071 
3072 static const struct bpf_func_proto bpf_msg_pop_data_proto = {
3073 	.func		= bpf_msg_pop_data,
3074 	.gpl_only	= false,
3075 	.ret_type	= RET_INTEGER,
3076 	.arg1_type	= ARG_PTR_TO_CTX,
3077 	.arg2_type	= ARG_ANYTHING,
3078 	.arg3_type	= ARG_ANYTHING,
3079 	.arg4_type	= ARG_ANYTHING,
3080 };
3081 
3082 #ifdef CONFIG_CGROUP_NET_CLASSID
BPF_CALL_0(bpf_get_cgroup_classid_curr)3083 BPF_CALL_0(bpf_get_cgroup_classid_curr)
3084 {
3085 	return __task_get_classid(current);
3086 }
3087 
3088 const struct bpf_func_proto bpf_get_cgroup_classid_curr_proto = {
3089 	.func		= bpf_get_cgroup_classid_curr,
3090 	.gpl_only	= false,
3091 	.ret_type	= RET_INTEGER,
3092 };
3093 
BPF_CALL_1(bpf_skb_cgroup_classid,const struct sk_buff *,skb)3094 BPF_CALL_1(bpf_skb_cgroup_classid, const struct sk_buff *, skb)
3095 {
3096 	struct sock *sk = skb_to_full_sk(skb);
3097 
3098 	if (!sk || !sk_fullsock(sk))
3099 		return 0;
3100 
3101 	return sock_cgroup_classid(&sk->sk_cgrp_data);
3102 }
3103 
3104 static const struct bpf_func_proto bpf_skb_cgroup_classid_proto = {
3105 	.func		= bpf_skb_cgroup_classid,
3106 	.gpl_only	= false,
3107 	.ret_type	= RET_INTEGER,
3108 	.arg1_type	= ARG_PTR_TO_CTX,
3109 };
3110 #endif
3111 
BPF_CALL_1(bpf_get_cgroup_classid,const struct sk_buff *,skb)3112 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
3113 {
3114 	return task_get_classid(skb);
3115 }
3116 
3117 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
3118 	.func           = bpf_get_cgroup_classid,
3119 	.gpl_only       = false,
3120 	.ret_type       = RET_INTEGER,
3121 	.arg1_type      = ARG_PTR_TO_CTX,
3122 };
3123 
BPF_CALL_1(bpf_get_route_realm,const struct sk_buff *,skb)3124 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
3125 {
3126 	return dst_tclassid(skb);
3127 }
3128 
3129 static const struct bpf_func_proto bpf_get_route_realm_proto = {
3130 	.func           = bpf_get_route_realm,
3131 	.gpl_only       = false,
3132 	.ret_type       = RET_INTEGER,
3133 	.arg1_type      = ARG_PTR_TO_CTX,
3134 };
3135 
BPF_CALL_1(bpf_get_hash_recalc,struct sk_buff *,skb)3136 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
3137 {
3138 	/* If skb_clear_hash() was called due to mangling, we can
3139 	 * trigger SW recalculation here. Later access to hash
3140 	 * can then use the inline skb->hash via context directly
3141 	 * instead of calling this helper again.
3142 	 */
3143 	return skb_get_hash(skb);
3144 }
3145 
3146 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
3147 	.func		= bpf_get_hash_recalc,
3148 	.gpl_only	= false,
3149 	.ret_type	= RET_INTEGER,
3150 	.arg1_type	= ARG_PTR_TO_CTX,
3151 };
3152 
BPF_CALL_1(bpf_set_hash_invalid,struct sk_buff *,skb)3153 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
3154 {
3155 	/* After all direct packet write, this can be used once for
3156 	 * triggering a lazy recalc on next skb_get_hash() invocation.
3157 	 */
3158 	skb_clear_hash(skb);
3159 	return 0;
3160 }
3161 
3162 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
3163 	.func		= bpf_set_hash_invalid,
3164 	.gpl_only	= false,
3165 	.ret_type	= RET_INTEGER,
3166 	.arg1_type	= ARG_PTR_TO_CTX,
3167 };
3168 
BPF_CALL_2(bpf_set_hash,struct sk_buff *,skb,u32,hash)3169 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
3170 {
3171 	/* Set user specified hash as L4(+), so that it gets returned
3172 	 * on skb_get_hash() call unless BPF prog later on triggers a
3173 	 * skb_clear_hash().
3174 	 */
3175 	__skb_set_sw_hash(skb, hash, true);
3176 	return 0;
3177 }
3178 
3179 static const struct bpf_func_proto bpf_set_hash_proto = {
3180 	.func		= bpf_set_hash,
3181 	.gpl_only	= false,
3182 	.ret_type	= RET_INTEGER,
3183 	.arg1_type	= ARG_PTR_TO_CTX,
3184 	.arg2_type	= ARG_ANYTHING,
3185 };
3186 
BPF_CALL_3(bpf_skb_vlan_push,struct sk_buff *,skb,__be16,vlan_proto,u16,vlan_tci)3187 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
3188 	   u16, vlan_tci)
3189 {
3190 	int ret;
3191 
3192 	if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
3193 		     vlan_proto != htons(ETH_P_8021AD)))
3194 		vlan_proto = htons(ETH_P_8021Q);
3195 
3196 	bpf_push_mac_rcsum(skb);
3197 	ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
3198 	bpf_pull_mac_rcsum(skb);
3199 
3200 	bpf_compute_data_pointers(skb);
3201 	return ret;
3202 }
3203 
3204 static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
3205 	.func           = bpf_skb_vlan_push,
3206 	.gpl_only       = false,
3207 	.ret_type       = RET_INTEGER,
3208 	.arg1_type      = ARG_PTR_TO_CTX,
3209 	.arg2_type      = ARG_ANYTHING,
3210 	.arg3_type      = ARG_ANYTHING,
3211 };
3212 
BPF_CALL_1(bpf_skb_vlan_pop,struct sk_buff *,skb)3213 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
3214 {
3215 	int ret;
3216 
3217 	bpf_push_mac_rcsum(skb);
3218 	ret = skb_vlan_pop(skb);
3219 	bpf_pull_mac_rcsum(skb);
3220 
3221 	bpf_compute_data_pointers(skb);
3222 	return ret;
3223 }
3224 
3225 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
3226 	.func           = bpf_skb_vlan_pop,
3227 	.gpl_only       = false,
3228 	.ret_type       = RET_INTEGER,
3229 	.arg1_type      = ARG_PTR_TO_CTX,
3230 };
3231 
bpf_skb_generic_push(struct sk_buff * skb,u32 off,u32 len)3232 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
3233 {
3234 	/* Caller already did skb_cow() with len as headroom,
3235 	 * so no need to do it here.
3236 	 */
3237 	skb_push(skb, len);
3238 	memmove(skb->data, skb->data + len, off);
3239 	memset(skb->data + off, 0, len);
3240 
3241 	/* No skb_postpush_rcsum(skb, skb->data + off, len)
3242 	 * needed here as it does not change the skb->csum
3243 	 * result for checksum complete when summing over
3244 	 * zeroed blocks.
3245 	 */
3246 	return 0;
3247 }
3248 
bpf_skb_generic_pop(struct sk_buff * skb,u32 off,u32 len)3249 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
3250 {
3251 	void *old_data;
3252 
3253 	/* skb_ensure_writable() is not needed here, as we're
3254 	 * already working on an uncloned skb.
3255 	 */
3256 	if (unlikely(!pskb_may_pull(skb, off + len)))
3257 		return -ENOMEM;
3258 
3259 	old_data = skb->data;
3260 	__skb_pull(skb, len);
3261 	skb_postpull_rcsum(skb, old_data + off, len);
3262 	memmove(skb->data, old_data, off);
3263 
3264 	return 0;
3265 }
3266 
bpf_skb_net_hdr_push(struct sk_buff * skb,u32 off,u32 len)3267 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
3268 {
3269 	bool trans_same = skb->transport_header == skb->network_header;
3270 	int ret;
3271 
3272 	/* There's no need for __skb_push()/__skb_pull() pair to
3273 	 * get to the start of the mac header as we're guaranteed
3274 	 * to always start from here under eBPF.
3275 	 */
3276 	ret = bpf_skb_generic_push(skb, off, len);
3277 	if (likely(!ret)) {
3278 		skb->mac_header -= len;
3279 		skb->network_header -= len;
3280 		if (trans_same)
3281 			skb->transport_header = skb->network_header;
3282 	}
3283 
3284 	return ret;
3285 }
3286 
bpf_skb_net_hdr_pop(struct sk_buff * skb,u32 off,u32 len)3287 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
3288 {
3289 	bool trans_same = skb->transport_header == skb->network_header;
3290 	int ret;
3291 
3292 	/* Same here, __skb_push()/__skb_pull() pair not needed. */
3293 	ret = bpf_skb_generic_pop(skb, off, len);
3294 	if (likely(!ret)) {
3295 		skb->mac_header += len;
3296 		skb->network_header += len;
3297 		if (trans_same)
3298 			skb->transport_header = skb->network_header;
3299 	}
3300 
3301 	return ret;
3302 }
3303 
bpf_skb_proto_4_to_6(struct sk_buff * skb)3304 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
3305 {
3306 	const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3307 	u32 off = skb_mac_header_len(skb);
3308 	int ret;
3309 
3310 	ret = skb_cow(skb, len_diff);
3311 	if (unlikely(ret < 0))
3312 		return ret;
3313 
3314 	ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3315 	if (unlikely(ret < 0))
3316 		return ret;
3317 
3318 	if (skb_is_gso(skb)) {
3319 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3320 
3321 		/* SKB_GSO_TCPV4 needs to be changed into SKB_GSO_TCPV6. */
3322 		if (shinfo->gso_type & SKB_GSO_TCPV4) {
3323 			shinfo->gso_type &= ~SKB_GSO_TCPV4;
3324 			shinfo->gso_type |=  SKB_GSO_TCPV6;
3325 		}
3326 	}
3327 
3328 	skb->protocol = htons(ETH_P_IPV6);
3329 	skb_clear_hash(skb);
3330 
3331 	return 0;
3332 }
3333 
bpf_skb_proto_6_to_4(struct sk_buff * skb)3334 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
3335 {
3336 	const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3337 	u32 off = skb_mac_header_len(skb);
3338 	int ret;
3339 
3340 	ret = skb_unclone(skb, GFP_ATOMIC);
3341 	if (unlikely(ret < 0))
3342 		return ret;
3343 
3344 	ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3345 	if (unlikely(ret < 0))
3346 		return ret;
3347 
3348 	if (skb_is_gso(skb)) {
3349 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3350 
3351 		/* SKB_GSO_TCPV6 needs to be changed into SKB_GSO_TCPV4. */
3352 		if (shinfo->gso_type & SKB_GSO_TCPV6) {
3353 			shinfo->gso_type &= ~SKB_GSO_TCPV6;
3354 			shinfo->gso_type |=  SKB_GSO_TCPV4;
3355 		}
3356 	}
3357 
3358 	skb->protocol = htons(ETH_P_IP);
3359 	skb_clear_hash(skb);
3360 
3361 	return 0;
3362 }
3363 
bpf_skb_proto_xlat(struct sk_buff * skb,__be16 to_proto)3364 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
3365 {
3366 	__be16 from_proto = skb->protocol;
3367 
3368 	if (from_proto == htons(ETH_P_IP) &&
3369 	      to_proto == htons(ETH_P_IPV6))
3370 		return bpf_skb_proto_4_to_6(skb);
3371 
3372 	if (from_proto == htons(ETH_P_IPV6) &&
3373 	      to_proto == htons(ETH_P_IP))
3374 		return bpf_skb_proto_6_to_4(skb);
3375 
3376 	return -ENOTSUPP;
3377 }
3378 
BPF_CALL_3(bpf_skb_change_proto,struct sk_buff *,skb,__be16,proto,u64,flags)3379 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
3380 	   u64, flags)
3381 {
3382 	int ret;
3383 
3384 	if (unlikely(flags))
3385 		return -EINVAL;
3386 
3387 	/* General idea is that this helper does the basic groundwork
3388 	 * needed for changing the protocol, and eBPF program fills the
3389 	 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
3390 	 * and other helpers, rather than passing a raw buffer here.
3391 	 *
3392 	 * The rationale is to keep this minimal and without a need to
3393 	 * deal with raw packet data. F.e. even if we would pass buffers
3394 	 * here, the program still needs to call the bpf_lX_csum_replace()
3395 	 * helpers anyway. Plus, this way we keep also separation of
3396 	 * concerns, since f.e. bpf_skb_store_bytes() should only take
3397 	 * care of stores.
3398 	 *
3399 	 * Currently, additional options and extension header space are
3400 	 * not supported, but flags register is reserved so we can adapt
3401 	 * that. For offloads, we mark packet as dodgy, so that headers
3402 	 * need to be verified first.
3403 	 */
3404 	ret = bpf_skb_proto_xlat(skb, proto);
3405 	bpf_compute_data_pointers(skb);
3406 	return ret;
3407 }
3408 
3409 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
3410 	.func		= bpf_skb_change_proto,
3411 	.gpl_only	= false,
3412 	.ret_type	= RET_INTEGER,
3413 	.arg1_type	= ARG_PTR_TO_CTX,
3414 	.arg2_type	= ARG_ANYTHING,
3415 	.arg3_type	= ARG_ANYTHING,
3416 };
3417 
BPF_CALL_2(bpf_skb_change_type,struct sk_buff *,skb,u32,pkt_type)3418 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
3419 {
3420 	/* We only allow a restricted subset to be changed for now. */
3421 	if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
3422 		     !skb_pkt_type_ok(pkt_type)))
3423 		return -EINVAL;
3424 
3425 	skb->pkt_type = pkt_type;
3426 	return 0;
3427 }
3428 
3429 static const struct bpf_func_proto bpf_skb_change_type_proto = {
3430 	.func		= bpf_skb_change_type,
3431 	.gpl_only	= false,
3432 	.ret_type	= RET_INTEGER,
3433 	.arg1_type	= ARG_PTR_TO_CTX,
3434 	.arg2_type	= ARG_ANYTHING,
3435 };
3436 
bpf_skb_net_base_len(const struct sk_buff * skb)3437 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
3438 {
3439 	switch (skb->protocol) {
3440 	case htons(ETH_P_IP):
3441 		return sizeof(struct iphdr);
3442 	case htons(ETH_P_IPV6):
3443 		return sizeof(struct ipv6hdr);
3444 	default:
3445 		return ~0U;
3446 	}
3447 }
3448 
3449 #define BPF_F_ADJ_ROOM_ENCAP_L3_MASK	(BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | \
3450 					 BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3451 
3452 #define BPF_F_ADJ_ROOM_DECAP_L3_MASK	(BPF_F_ADJ_ROOM_DECAP_L3_IPV4 | \
3453 					 BPF_F_ADJ_ROOM_DECAP_L3_IPV6)
3454 
3455 #define BPF_F_ADJ_ROOM_MASK		(BPF_F_ADJ_ROOM_FIXED_GSO | \
3456 					 BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \
3457 					 BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \
3458 					 BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \
3459 					 BPF_F_ADJ_ROOM_ENCAP_L2_ETH | \
3460 					 BPF_F_ADJ_ROOM_ENCAP_L2( \
3461 					  BPF_ADJ_ROOM_ENCAP_L2_MASK) | \
3462 					 BPF_F_ADJ_ROOM_DECAP_L3_MASK)
3463 
bpf_skb_net_grow(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3464 static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff,
3465 			    u64 flags)
3466 {
3467 	u8 inner_mac_len = flags >> BPF_ADJ_ROOM_ENCAP_L2_SHIFT;
3468 	bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK;
3469 	u16 mac_len = 0, inner_net = 0, inner_trans = 0;
3470 	unsigned int gso_type = SKB_GSO_DODGY;
3471 	int ret;
3472 
3473 	if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3474 		/* udp gso_size delineates datagrams, only allow if fixed */
3475 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3476 		    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3477 			return -ENOTSUPP;
3478 	}
3479 
3480 	ret = skb_cow_head(skb, len_diff);
3481 	if (unlikely(ret < 0))
3482 		return ret;
3483 
3484 	if (encap) {
3485 		if (skb->protocol != htons(ETH_P_IP) &&
3486 		    skb->protocol != htons(ETH_P_IPV6))
3487 			return -ENOTSUPP;
3488 
3489 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 &&
3490 		    flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3491 			return -EINVAL;
3492 
3493 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE &&
3494 		    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3495 			return -EINVAL;
3496 
3497 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH &&
3498 		    inner_mac_len < ETH_HLEN)
3499 			return -EINVAL;
3500 
3501 		if (skb->encapsulation)
3502 			return -EALREADY;
3503 
3504 		mac_len = skb->network_header - skb->mac_header;
3505 		inner_net = skb->network_header;
3506 		if (inner_mac_len > len_diff)
3507 			return -EINVAL;
3508 		inner_trans = skb->transport_header;
3509 	}
3510 
3511 	ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3512 	if (unlikely(ret < 0))
3513 		return ret;
3514 
3515 	if (encap) {
3516 		skb->inner_mac_header = inner_net - inner_mac_len;
3517 		skb->inner_network_header = inner_net;
3518 		skb->inner_transport_header = inner_trans;
3519 
3520 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH)
3521 			skb_set_inner_protocol(skb, htons(ETH_P_TEB));
3522 		else
3523 			skb_set_inner_protocol(skb, skb->protocol);
3524 
3525 		skb->encapsulation = 1;
3526 		skb_set_network_header(skb, mac_len);
3527 
3528 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3529 			gso_type |= SKB_GSO_UDP_TUNNEL;
3530 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE)
3531 			gso_type |= SKB_GSO_GRE;
3532 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3533 			gso_type |= SKB_GSO_IPXIP6;
3534 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3535 			gso_type |= SKB_GSO_IPXIP4;
3536 
3537 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||
3538 		    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) {
3539 			int nh_len = flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 ?
3540 					sizeof(struct ipv6hdr) :
3541 					sizeof(struct iphdr);
3542 
3543 			skb_set_transport_header(skb, mac_len + nh_len);
3544 		}
3545 
3546 		/* Match skb->protocol to new outer l3 protocol */
3547 		if (skb->protocol == htons(ETH_P_IP) &&
3548 		    flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3549 			skb->protocol = htons(ETH_P_IPV6);
3550 		else if (skb->protocol == htons(ETH_P_IPV6) &&
3551 			 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3552 			skb->protocol = htons(ETH_P_IP);
3553 	}
3554 
3555 	if (skb_is_gso(skb)) {
3556 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3557 
3558 		/* Header must be checked, and gso_segs recomputed. */
3559 		shinfo->gso_type |= gso_type;
3560 		shinfo->gso_segs = 0;
3561 
3562 		/* Due to header growth, MSS needs to be downgraded.
3563 		 * There is a BUG_ON() when segmenting the frag_list with
3564 		 * head_frag true, so linearize the skb after downgrading
3565 		 * the MSS.
3566 		 */
3567 		if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO)) {
3568 			skb_decrease_gso_size(shinfo, len_diff);
3569 			if (shinfo->frag_list)
3570 				return skb_linearize(skb);
3571 		}
3572 	}
3573 
3574 	return 0;
3575 }
3576 
bpf_skb_net_shrink(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3577 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff,
3578 			      u64 flags)
3579 {
3580 	int ret;
3581 
3582 	if (unlikely(flags & ~(BPF_F_ADJ_ROOM_FIXED_GSO |
3583 			       BPF_F_ADJ_ROOM_DECAP_L3_MASK |
3584 			       BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3585 		return -EINVAL;
3586 
3587 	if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3588 		/* udp gso_size delineates datagrams, only allow if fixed */
3589 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3590 		    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3591 			return -ENOTSUPP;
3592 	}
3593 
3594 	ret = skb_unclone(skb, GFP_ATOMIC);
3595 	if (unlikely(ret < 0))
3596 		return ret;
3597 
3598 	ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3599 	if (unlikely(ret < 0))
3600 		return ret;
3601 
3602 	/* Match skb->protocol to new outer l3 protocol */
3603 	if (skb->protocol == htons(ETH_P_IP) &&
3604 	    flags & BPF_F_ADJ_ROOM_DECAP_L3_IPV6)
3605 		skb->protocol = htons(ETH_P_IPV6);
3606 	else if (skb->protocol == htons(ETH_P_IPV6) &&
3607 		 flags & BPF_F_ADJ_ROOM_DECAP_L3_IPV4)
3608 		skb->protocol = htons(ETH_P_IP);
3609 
3610 	if (skb_is_gso(skb)) {
3611 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3612 
3613 		/* Due to header shrink, MSS can be upgraded. */
3614 		if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3615 			skb_increase_gso_size(shinfo, len_diff);
3616 
3617 		/* Header must be checked, and gso_segs recomputed. */
3618 		shinfo->gso_type |= SKB_GSO_DODGY;
3619 		shinfo->gso_segs = 0;
3620 	}
3621 
3622 	return 0;
3623 }
3624 
3625 #define BPF_SKB_MAX_LEN SKB_MAX_ALLOC
3626 
BPF_CALL_4(sk_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3627 BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3628 	   u32, mode, u64, flags)
3629 {
3630 	u32 len_diff_abs = abs(len_diff);
3631 	bool shrink = len_diff < 0;
3632 	int ret = 0;
3633 
3634 	if (unlikely(flags || mode))
3635 		return -EINVAL;
3636 	if (unlikely(len_diff_abs > 0xfffU))
3637 		return -EFAULT;
3638 
3639 	if (!shrink) {
3640 		ret = skb_cow(skb, len_diff);
3641 		if (unlikely(ret < 0))
3642 			return ret;
3643 		__skb_push(skb, len_diff_abs);
3644 		memset(skb->data, 0, len_diff_abs);
3645 	} else {
3646 		if (unlikely(!pskb_may_pull(skb, len_diff_abs)))
3647 			return -ENOMEM;
3648 		__skb_pull(skb, len_diff_abs);
3649 	}
3650 	if (tls_sw_has_ctx_rx(skb->sk)) {
3651 		struct strp_msg *rxm = strp_msg(skb);
3652 
3653 		rxm->full_len += len_diff;
3654 	}
3655 	return ret;
3656 }
3657 
3658 static const struct bpf_func_proto sk_skb_adjust_room_proto = {
3659 	.func		= sk_skb_adjust_room,
3660 	.gpl_only	= false,
3661 	.ret_type	= RET_INTEGER,
3662 	.arg1_type	= ARG_PTR_TO_CTX,
3663 	.arg2_type	= ARG_ANYTHING,
3664 	.arg3_type	= ARG_ANYTHING,
3665 	.arg4_type	= ARG_ANYTHING,
3666 };
3667 
BPF_CALL_4(bpf_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3668 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3669 	   u32, mode, u64, flags)
3670 {
3671 	u32 len_cur, len_diff_abs = abs(len_diff);
3672 	u32 len_min = bpf_skb_net_base_len(skb);
3673 	u32 len_max = BPF_SKB_MAX_LEN;
3674 	__be16 proto = skb->protocol;
3675 	bool shrink = len_diff < 0;
3676 	u32 off;
3677 	int ret;
3678 
3679 	if (unlikely(flags & ~(BPF_F_ADJ_ROOM_MASK |
3680 			       BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3681 		return -EINVAL;
3682 	if (unlikely(len_diff_abs > 0xfffU))
3683 		return -EFAULT;
3684 	if (unlikely(proto != htons(ETH_P_IP) &&
3685 		     proto != htons(ETH_P_IPV6)))
3686 		return -ENOTSUPP;
3687 
3688 	off = skb_mac_header_len(skb);
3689 	switch (mode) {
3690 	case BPF_ADJ_ROOM_NET:
3691 		off += bpf_skb_net_base_len(skb);
3692 		break;
3693 	case BPF_ADJ_ROOM_MAC:
3694 		break;
3695 	default:
3696 		return -ENOTSUPP;
3697 	}
3698 
3699 	if (flags & BPF_F_ADJ_ROOM_DECAP_L3_MASK) {
3700 		if (!shrink)
3701 			return -EINVAL;
3702 
3703 		switch (flags & BPF_F_ADJ_ROOM_DECAP_L3_MASK) {
3704 		case BPF_F_ADJ_ROOM_DECAP_L3_IPV4:
3705 			len_min = sizeof(struct iphdr);
3706 			break;
3707 		case BPF_F_ADJ_ROOM_DECAP_L3_IPV6:
3708 			len_min = sizeof(struct ipv6hdr);
3709 			break;
3710 		default:
3711 			return -EINVAL;
3712 		}
3713 	}
3714 
3715 	len_cur = skb->len - skb_network_offset(skb);
3716 	if ((shrink && (len_diff_abs >= len_cur ||
3717 			len_cur - len_diff_abs < len_min)) ||
3718 	    (!shrink && (skb->len + len_diff_abs > len_max &&
3719 			 !skb_is_gso(skb))))
3720 		return -ENOTSUPP;
3721 
3722 	ret = shrink ? bpf_skb_net_shrink(skb, off, len_diff_abs, flags) :
3723 		       bpf_skb_net_grow(skb, off, len_diff_abs, flags);
3724 	if (!ret && !(flags & BPF_F_ADJ_ROOM_NO_CSUM_RESET))
3725 		__skb_reset_checksum_unnecessary(skb);
3726 
3727 	bpf_compute_data_pointers(skb);
3728 	return ret;
3729 }
3730 
3731 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
3732 	.func		= bpf_skb_adjust_room,
3733 	.gpl_only	= false,
3734 	.ret_type	= RET_INTEGER,
3735 	.arg1_type	= ARG_PTR_TO_CTX,
3736 	.arg2_type	= ARG_ANYTHING,
3737 	.arg3_type	= ARG_ANYTHING,
3738 	.arg4_type	= ARG_ANYTHING,
3739 };
3740 
__bpf_skb_min_len(const struct sk_buff * skb)3741 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
3742 {
3743 	int offset = skb_network_offset(skb);
3744 	u32 min_len = 0;
3745 
3746 	if (offset > 0)
3747 		min_len = offset;
3748 	if (skb_transport_header_was_set(skb)) {
3749 		offset = skb_transport_offset(skb);
3750 		if (offset > 0)
3751 			min_len = offset;
3752 	}
3753 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
3754 		offset = skb_checksum_start_offset(skb) +
3755 			 skb->csum_offset + sizeof(__sum16);
3756 		if (offset > 0)
3757 			min_len = offset;
3758 	}
3759 	return min_len;
3760 }
3761 
bpf_skb_grow_rcsum(struct sk_buff * skb,unsigned int new_len)3762 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
3763 {
3764 	unsigned int old_len = skb->len;
3765 	int ret;
3766 
3767 	ret = __skb_grow_rcsum(skb, new_len);
3768 	if (!ret)
3769 		memset(skb->data + old_len, 0, new_len - old_len);
3770 	return ret;
3771 }
3772 
bpf_skb_trim_rcsum(struct sk_buff * skb,unsigned int new_len)3773 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
3774 {
3775 	return __skb_trim_rcsum(skb, new_len);
3776 }
3777 
__bpf_skb_change_tail(struct sk_buff * skb,u32 new_len,u64 flags)3778 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
3779 					u64 flags)
3780 {
3781 	u32 max_len = BPF_SKB_MAX_LEN;
3782 	u32 min_len = __bpf_skb_min_len(skb);
3783 	int ret;
3784 
3785 	if (unlikely(flags || new_len > max_len || new_len < min_len))
3786 		return -EINVAL;
3787 	if (skb->encapsulation)
3788 		return -ENOTSUPP;
3789 
3790 	/* The basic idea of this helper is that it's performing the
3791 	 * needed work to either grow or trim an skb, and eBPF program
3792 	 * rewrites the rest via helpers like bpf_skb_store_bytes(),
3793 	 * bpf_lX_csum_replace() and others rather than passing a raw
3794 	 * buffer here. This one is a slow path helper and intended
3795 	 * for replies with control messages.
3796 	 *
3797 	 * Like in bpf_skb_change_proto(), we want to keep this rather
3798 	 * minimal and without protocol specifics so that we are able
3799 	 * to separate concerns as in bpf_skb_store_bytes() should only
3800 	 * be the one responsible for writing buffers.
3801 	 *
3802 	 * It's really expected to be a slow path operation here for
3803 	 * control message replies, so we're implicitly linearizing,
3804 	 * uncloning and drop offloads from the skb by this.
3805 	 */
3806 	ret = __bpf_try_make_writable(skb, skb->len);
3807 	if (!ret) {
3808 		if (new_len > skb->len)
3809 			ret = bpf_skb_grow_rcsum(skb, new_len);
3810 		else if (new_len < skb->len)
3811 			ret = bpf_skb_trim_rcsum(skb, new_len);
3812 		if (!ret && skb_is_gso(skb))
3813 			skb_gso_reset(skb);
3814 	}
3815 	return ret;
3816 }
3817 
BPF_CALL_3(bpf_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3818 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3819 	   u64, flags)
3820 {
3821 	int ret = __bpf_skb_change_tail(skb, new_len, flags);
3822 
3823 	bpf_compute_data_pointers(skb);
3824 	return ret;
3825 }
3826 
3827 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
3828 	.func		= bpf_skb_change_tail,
3829 	.gpl_only	= false,
3830 	.ret_type	= RET_INTEGER,
3831 	.arg1_type	= ARG_PTR_TO_CTX,
3832 	.arg2_type	= ARG_ANYTHING,
3833 	.arg3_type	= ARG_ANYTHING,
3834 };
3835 
BPF_CALL_3(sk_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3836 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3837 	   u64, flags)
3838 {
3839 	return __bpf_skb_change_tail(skb, new_len, flags);
3840 }
3841 
3842 static const struct bpf_func_proto sk_skb_change_tail_proto = {
3843 	.func		= sk_skb_change_tail,
3844 	.gpl_only	= false,
3845 	.ret_type	= RET_INTEGER,
3846 	.arg1_type	= ARG_PTR_TO_CTX,
3847 	.arg2_type	= ARG_ANYTHING,
3848 	.arg3_type	= ARG_ANYTHING,
3849 };
3850 
__bpf_skb_change_head(struct sk_buff * skb,u32 head_room,u64 flags)3851 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
3852 					u64 flags)
3853 {
3854 	u32 max_len = BPF_SKB_MAX_LEN;
3855 	u32 new_len = skb->len + head_room;
3856 	int ret;
3857 
3858 	if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
3859 		     new_len < skb->len))
3860 		return -EINVAL;
3861 
3862 	ret = skb_cow(skb, head_room);
3863 	if (likely(!ret)) {
3864 		/* Idea for this helper is that we currently only
3865 		 * allow to expand on mac header. This means that
3866 		 * skb->protocol network header, etc, stay as is.
3867 		 * Compared to bpf_skb_change_tail(), we're more
3868 		 * flexible due to not needing to linearize or
3869 		 * reset GSO. Intention for this helper is to be
3870 		 * used by an L3 skb that needs to push mac header
3871 		 * for redirection into L2 device.
3872 		 */
3873 		__skb_push(skb, head_room);
3874 		memset(skb->data, 0, head_room);
3875 		skb_reset_mac_header(skb);
3876 		skb_reset_mac_len(skb);
3877 	}
3878 
3879 	return ret;
3880 }
3881 
BPF_CALL_3(bpf_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3882 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
3883 	   u64, flags)
3884 {
3885 	int ret = __bpf_skb_change_head(skb, head_room, flags);
3886 
3887 	bpf_compute_data_pointers(skb);
3888 	return ret;
3889 }
3890 
3891 static const struct bpf_func_proto bpf_skb_change_head_proto = {
3892 	.func		= bpf_skb_change_head,
3893 	.gpl_only	= false,
3894 	.ret_type	= RET_INTEGER,
3895 	.arg1_type	= ARG_PTR_TO_CTX,
3896 	.arg2_type	= ARG_ANYTHING,
3897 	.arg3_type	= ARG_ANYTHING,
3898 };
3899 
BPF_CALL_3(sk_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3900 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
3901 	   u64, flags)
3902 {
3903 	return __bpf_skb_change_head(skb, head_room, flags);
3904 }
3905 
3906 static const struct bpf_func_proto sk_skb_change_head_proto = {
3907 	.func		= sk_skb_change_head,
3908 	.gpl_only	= false,
3909 	.ret_type	= RET_INTEGER,
3910 	.arg1_type	= ARG_PTR_TO_CTX,
3911 	.arg2_type	= ARG_ANYTHING,
3912 	.arg3_type	= ARG_ANYTHING,
3913 };
3914 
BPF_CALL_1(bpf_xdp_get_buff_len,struct xdp_buff *,xdp)3915 BPF_CALL_1(bpf_xdp_get_buff_len, struct xdp_buff*, xdp)
3916 {
3917 	return xdp_get_buff_len(xdp);
3918 }
3919 
3920 static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = {
3921 	.func		= bpf_xdp_get_buff_len,
3922 	.gpl_only	= false,
3923 	.ret_type	= RET_INTEGER,
3924 	.arg1_type	= ARG_PTR_TO_CTX,
3925 };
3926 
3927 BTF_ID_LIST_SINGLE(bpf_xdp_get_buff_len_bpf_ids, struct, xdp_buff)
3928 
3929 const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto = {
3930 	.func		= bpf_xdp_get_buff_len,
3931 	.gpl_only	= false,
3932 	.arg1_type	= ARG_PTR_TO_BTF_ID,
3933 	.arg1_btf_id	= &bpf_xdp_get_buff_len_bpf_ids[0],
3934 };
3935 
xdp_get_metalen(const struct xdp_buff * xdp)3936 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
3937 {
3938 	return xdp_data_meta_unsupported(xdp) ? 0 :
3939 	       xdp->data - xdp->data_meta;
3940 }
3941 
BPF_CALL_2(bpf_xdp_adjust_head,struct xdp_buff *,xdp,int,offset)3942 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
3943 {
3944 	void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3945 	unsigned long metalen = xdp_get_metalen(xdp);
3946 	void *data_start = xdp_frame_end + metalen;
3947 	void *data = xdp->data + offset;
3948 
3949 	if (unlikely(data < data_start ||
3950 		     data > xdp->data_end - ETH_HLEN))
3951 		return -EINVAL;
3952 
3953 	if (metalen)
3954 		memmove(xdp->data_meta + offset,
3955 			xdp->data_meta, metalen);
3956 	xdp->data_meta += offset;
3957 	xdp->data = data;
3958 
3959 	return 0;
3960 }
3961 
3962 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
3963 	.func		= bpf_xdp_adjust_head,
3964 	.gpl_only	= false,
3965 	.ret_type	= RET_INTEGER,
3966 	.arg1_type	= ARG_PTR_TO_CTX,
3967 	.arg2_type	= ARG_ANYTHING,
3968 };
3969 
bpf_xdp_copy_buf(struct xdp_buff * xdp,unsigned long off,void * buf,unsigned long len,bool flush)3970 void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
3971 		      void *buf, unsigned long len, bool flush)
3972 {
3973 	unsigned long ptr_len, ptr_off = 0;
3974 	skb_frag_t *next_frag, *end_frag;
3975 	struct skb_shared_info *sinfo;
3976 	void *src, *dst;
3977 	u8 *ptr_buf;
3978 
3979 	if (likely(xdp->data_end - xdp->data >= off + len)) {
3980 		src = flush ? buf : xdp->data + off;
3981 		dst = flush ? xdp->data + off : buf;
3982 		memcpy(dst, src, len);
3983 		return;
3984 	}
3985 
3986 	sinfo = xdp_get_shared_info_from_buff(xdp);
3987 	end_frag = &sinfo->frags[sinfo->nr_frags];
3988 	next_frag = &sinfo->frags[0];
3989 
3990 	ptr_len = xdp->data_end - xdp->data;
3991 	ptr_buf = xdp->data;
3992 
3993 	while (true) {
3994 		if (off < ptr_off + ptr_len) {
3995 			unsigned long copy_off = off - ptr_off;
3996 			unsigned long copy_len = min(len, ptr_len - copy_off);
3997 
3998 			src = flush ? buf : ptr_buf + copy_off;
3999 			dst = flush ? ptr_buf + copy_off : buf;
4000 			memcpy(dst, src, copy_len);
4001 
4002 			off += copy_len;
4003 			len -= copy_len;
4004 			buf += copy_len;
4005 		}
4006 
4007 		if (!len || next_frag == end_frag)
4008 			break;
4009 
4010 		ptr_off += ptr_len;
4011 		ptr_buf = skb_frag_address(next_frag);
4012 		ptr_len = skb_frag_size(next_frag);
4013 		next_frag++;
4014 	}
4015 }
4016 
bpf_xdp_pointer(struct xdp_buff * xdp,u32 offset,u32 len)4017 void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
4018 {
4019 	u32 size = xdp->data_end - xdp->data;
4020 	struct skb_shared_info *sinfo;
4021 	void *addr = xdp->data;
4022 	int i;
4023 
4024 	if (unlikely(offset > 0xffff || len > 0xffff))
4025 		return ERR_PTR(-EFAULT);
4026 
4027 	if (unlikely(offset + len > xdp_get_buff_len(xdp)))
4028 		return ERR_PTR(-EINVAL);
4029 
4030 	if (likely(offset < size)) /* linear area */
4031 		goto out;
4032 
4033 	sinfo = xdp_get_shared_info_from_buff(xdp);
4034 	offset -= size;
4035 	for (i = 0; i < sinfo->nr_frags; i++) { /* paged area */
4036 		u32 frag_size = skb_frag_size(&sinfo->frags[i]);
4037 
4038 		if  (offset < frag_size) {
4039 			addr = skb_frag_address(&sinfo->frags[i]);
4040 			size = frag_size;
4041 			break;
4042 		}
4043 		offset -= frag_size;
4044 	}
4045 out:
4046 	return offset + len <= size ? addr + offset : NULL;
4047 }
4048 
BPF_CALL_4(bpf_xdp_load_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)4049 BPF_CALL_4(bpf_xdp_load_bytes, struct xdp_buff *, xdp, u32, offset,
4050 	   void *, buf, u32, len)
4051 {
4052 	void *ptr;
4053 
4054 	ptr = bpf_xdp_pointer(xdp, offset, len);
4055 	if (IS_ERR(ptr))
4056 		return PTR_ERR(ptr);
4057 
4058 	if (!ptr)
4059 		bpf_xdp_copy_buf(xdp, offset, buf, len, false);
4060 	else
4061 		memcpy(buf, ptr, len);
4062 
4063 	return 0;
4064 }
4065 
4066 static const struct bpf_func_proto bpf_xdp_load_bytes_proto = {
4067 	.func		= bpf_xdp_load_bytes,
4068 	.gpl_only	= false,
4069 	.ret_type	= RET_INTEGER,
4070 	.arg1_type	= ARG_PTR_TO_CTX,
4071 	.arg2_type	= ARG_ANYTHING,
4072 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
4073 	.arg4_type	= ARG_CONST_SIZE,
4074 };
4075 
__bpf_xdp_load_bytes(struct xdp_buff * xdp,u32 offset,void * buf,u32 len)4076 int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len)
4077 {
4078 	return ____bpf_xdp_load_bytes(xdp, offset, buf, len);
4079 }
4080 
BPF_CALL_4(bpf_xdp_store_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)4081 BPF_CALL_4(bpf_xdp_store_bytes, struct xdp_buff *, xdp, u32, offset,
4082 	   void *, buf, u32, len)
4083 {
4084 	void *ptr;
4085 
4086 	ptr = bpf_xdp_pointer(xdp, offset, len);
4087 	if (IS_ERR(ptr))
4088 		return PTR_ERR(ptr);
4089 
4090 	if (!ptr)
4091 		bpf_xdp_copy_buf(xdp, offset, buf, len, true);
4092 	else
4093 		memcpy(ptr, buf, len);
4094 
4095 	return 0;
4096 }
4097 
4098 static const struct bpf_func_proto bpf_xdp_store_bytes_proto = {
4099 	.func		= bpf_xdp_store_bytes,
4100 	.gpl_only	= false,
4101 	.ret_type	= RET_INTEGER,
4102 	.arg1_type	= ARG_PTR_TO_CTX,
4103 	.arg2_type	= ARG_ANYTHING,
4104 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
4105 	.arg4_type	= ARG_CONST_SIZE,
4106 };
4107 
__bpf_xdp_store_bytes(struct xdp_buff * xdp,u32 offset,void * buf,u32 len)4108 int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len)
4109 {
4110 	return ____bpf_xdp_store_bytes(xdp, offset, buf, len);
4111 }
4112 
bpf_xdp_frags_increase_tail(struct xdp_buff * xdp,int offset)4113 static int bpf_xdp_frags_increase_tail(struct xdp_buff *xdp, int offset)
4114 {
4115 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
4116 	skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags - 1];
4117 	struct xdp_rxq_info *rxq = xdp->rxq;
4118 	unsigned int tailroom;
4119 
4120 	if (!rxq->frag_size || rxq->frag_size > xdp->frame_sz)
4121 		return -EOPNOTSUPP;
4122 
4123 	tailroom = rxq->frag_size - skb_frag_size(frag) - skb_frag_off(frag);
4124 	if (unlikely(offset > tailroom))
4125 		return -EINVAL;
4126 
4127 	memset(skb_frag_address(frag) + skb_frag_size(frag), 0, offset);
4128 	skb_frag_size_add(frag, offset);
4129 	sinfo->xdp_frags_size += offset;
4130 	if (rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL)
4131 		xsk_buff_get_tail(xdp)->data_end += offset;
4132 
4133 	return 0;
4134 }
4135 
bpf_xdp_shrink_data_zc(struct xdp_buff * xdp,int shrink,struct xdp_mem_info * mem_info,bool release)4136 static void bpf_xdp_shrink_data_zc(struct xdp_buff *xdp, int shrink,
4137 				   struct xdp_mem_info *mem_info, bool release)
4138 {
4139 	struct xdp_buff *zc_frag = xsk_buff_get_tail(xdp);
4140 
4141 	if (release) {
4142 		xsk_buff_del_tail(zc_frag);
4143 		__xdp_return(NULL, mem_info, false, zc_frag);
4144 	} else {
4145 		zc_frag->data_end -= shrink;
4146 	}
4147 }
4148 
bpf_xdp_shrink_data(struct xdp_buff * xdp,skb_frag_t * frag,int shrink)4149 static bool bpf_xdp_shrink_data(struct xdp_buff *xdp, skb_frag_t *frag,
4150 				int shrink)
4151 {
4152 	struct xdp_mem_info *mem_info = &xdp->rxq->mem;
4153 	bool release = skb_frag_size(frag) == shrink;
4154 
4155 	if (mem_info->type == MEM_TYPE_XSK_BUFF_POOL) {
4156 		bpf_xdp_shrink_data_zc(xdp, shrink, mem_info, release);
4157 		goto out;
4158 	}
4159 
4160 	if (release) {
4161 		struct page *page = skb_frag_page(frag);
4162 
4163 		__xdp_return(page_address(page), mem_info, false, NULL);
4164 	}
4165 
4166 out:
4167 	return release;
4168 }
4169 
bpf_xdp_frags_shrink_tail(struct xdp_buff * xdp,int offset)4170 static int bpf_xdp_frags_shrink_tail(struct xdp_buff *xdp, int offset)
4171 {
4172 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
4173 	int i, n_frags_free = 0, len_free = 0;
4174 
4175 	if (unlikely(offset > (int)xdp_get_buff_len(xdp) - ETH_HLEN))
4176 		return -EINVAL;
4177 
4178 	for (i = sinfo->nr_frags - 1; i >= 0 && offset > 0; i--) {
4179 		skb_frag_t *frag = &sinfo->frags[i];
4180 		int shrink = min_t(int, offset, skb_frag_size(frag));
4181 
4182 		len_free += shrink;
4183 		offset -= shrink;
4184 		if (bpf_xdp_shrink_data(xdp, frag, shrink)) {
4185 			n_frags_free++;
4186 		} else {
4187 			skb_frag_size_sub(frag, shrink);
4188 			break;
4189 		}
4190 	}
4191 	sinfo->nr_frags -= n_frags_free;
4192 	sinfo->xdp_frags_size -= len_free;
4193 
4194 	if (unlikely(!sinfo->nr_frags)) {
4195 		xdp_buff_clear_frags_flag(xdp);
4196 		xdp->data_end -= offset;
4197 	}
4198 
4199 	return 0;
4200 }
4201 
BPF_CALL_2(bpf_xdp_adjust_tail,struct xdp_buff *,xdp,int,offset)4202 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
4203 {
4204 	void *data_hard_end = xdp_data_hard_end(xdp); /* use xdp->frame_sz */
4205 	void *data_end = xdp->data_end + offset;
4206 
4207 	if (unlikely(xdp_buff_has_frags(xdp))) { /* non-linear xdp buff */
4208 		if (offset < 0)
4209 			return bpf_xdp_frags_shrink_tail(xdp, -offset);
4210 
4211 		return bpf_xdp_frags_increase_tail(xdp, offset);
4212 	}
4213 
4214 	/* Notice that xdp_data_hard_end have reserved some tailroom */
4215 	if (unlikely(data_end > data_hard_end))
4216 		return -EINVAL;
4217 
4218 	if (unlikely(data_end < xdp->data + ETH_HLEN))
4219 		return -EINVAL;
4220 
4221 	/* Clear memory area on grow, can contain uninit kernel memory */
4222 	if (offset > 0)
4223 		memset(xdp->data_end, 0, offset);
4224 
4225 	xdp->data_end = data_end;
4226 
4227 	return 0;
4228 }
4229 
4230 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
4231 	.func		= bpf_xdp_adjust_tail,
4232 	.gpl_only	= false,
4233 	.ret_type	= RET_INTEGER,
4234 	.arg1_type	= ARG_PTR_TO_CTX,
4235 	.arg2_type	= ARG_ANYTHING,
4236 };
4237 
BPF_CALL_2(bpf_xdp_adjust_meta,struct xdp_buff *,xdp,int,offset)4238 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
4239 {
4240 	void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
4241 	void *meta = xdp->data_meta + offset;
4242 	unsigned long metalen = xdp->data - meta;
4243 
4244 	if (xdp_data_meta_unsupported(xdp))
4245 		return -ENOTSUPP;
4246 	if (unlikely(meta < xdp_frame_end ||
4247 		     meta > xdp->data))
4248 		return -EINVAL;
4249 	if (unlikely(xdp_metalen_invalid(metalen)))
4250 		return -EACCES;
4251 
4252 	xdp->data_meta = meta;
4253 
4254 	return 0;
4255 }
4256 
4257 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
4258 	.func		= bpf_xdp_adjust_meta,
4259 	.gpl_only	= false,
4260 	.ret_type	= RET_INTEGER,
4261 	.arg1_type	= ARG_PTR_TO_CTX,
4262 	.arg2_type	= ARG_ANYTHING,
4263 };
4264 
4265 /**
4266  * DOC: xdp redirect
4267  *
4268  * XDP_REDIRECT works by a three-step process, implemented in the functions
4269  * below:
4270  *
4271  * 1. The bpf_redirect() and bpf_redirect_map() helpers will lookup the target
4272  *    of the redirect and store it (along with some other metadata) in a per-CPU
4273  *    struct bpf_redirect_info.
4274  *
4275  * 2. When the program returns the XDP_REDIRECT return code, the driver will
4276  *    call xdp_do_redirect() which will use the information in struct
4277  *    bpf_redirect_info to actually enqueue the frame into a map type-specific
4278  *    bulk queue structure.
4279  *
4280  * 3. Before exiting its NAPI poll loop, the driver will call
4281  *    xdp_do_flush(), which will flush all the different bulk queues,
4282  *    thus completing the redirect. Note that xdp_do_flush() must be
4283  *    called before napi_complete_done() in the driver, as the
4284  *    XDP_REDIRECT logic relies on being inside a single NAPI instance
4285  *    through to the xdp_do_flush() call for RCU protection of all
4286  *    in-kernel data structures.
4287  */
4288 /*
4289  * Pointers to the map entries will be kept around for this whole sequence of
4290  * steps, protected by RCU. However, there is no top-level rcu_read_lock() in
4291  * the core code; instead, the RCU protection relies on everything happening
4292  * inside a single NAPI poll sequence, which means it's between a pair of calls
4293  * to local_bh_disable()/local_bh_enable().
4294  *
4295  * The map entries are marked as __rcu and the map code makes sure to
4296  * dereference those pointers with rcu_dereference_check() in a way that works
4297  * for both sections that to hold an rcu_read_lock() and sections that are
4298  * called from NAPI without a separate rcu_read_lock(). The code below does not
4299  * use RCU annotations, but relies on those in the map code.
4300  */
xdp_do_flush(void)4301 void xdp_do_flush(void)
4302 {
4303 	__dev_flush();
4304 	__cpu_map_flush();
4305 	__xsk_map_flush();
4306 }
4307 EXPORT_SYMBOL_GPL(xdp_do_flush);
4308 
bpf_clear_redirect_map(struct bpf_map * map)4309 void bpf_clear_redirect_map(struct bpf_map *map)
4310 {
4311 	struct bpf_redirect_info *ri;
4312 	int cpu;
4313 
4314 	for_each_possible_cpu(cpu) {
4315 		ri = per_cpu_ptr(&bpf_redirect_info, cpu);
4316 		/* Avoid polluting remote cacheline due to writes if
4317 		 * not needed. Once we pass this test, we need the
4318 		 * cmpxchg() to make sure it hasn't been changed in
4319 		 * the meantime by remote CPU.
4320 		 */
4321 		if (unlikely(READ_ONCE(ri->map) == map))
4322 			cmpxchg(&ri->map, map, NULL);
4323 	}
4324 }
4325 
4326 DEFINE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
4327 EXPORT_SYMBOL_GPL(bpf_master_redirect_enabled_key);
4328 
xdp_master_redirect(struct xdp_buff * xdp)4329 u32 xdp_master_redirect(struct xdp_buff *xdp)
4330 {
4331 	struct net_device *master, *slave;
4332 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4333 
4334 	master = netdev_master_upper_dev_get_rcu(xdp->rxq->dev);
4335 	slave = master->netdev_ops->ndo_xdp_get_xmit_slave(master, xdp);
4336 	if (slave && slave != xdp->rxq->dev) {
4337 		/* The target device is different from the receiving device, so
4338 		 * redirect it to the new device.
4339 		 * Using XDP_REDIRECT gets the correct behaviour from XDP enabled
4340 		 * drivers to unmap the packet from their rx ring.
4341 		 */
4342 		ri->tgt_index = slave->ifindex;
4343 		ri->map_id = INT_MAX;
4344 		ri->map_type = BPF_MAP_TYPE_UNSPEC;
4345 		return XDP_REDIRECT;
4346 	}
4347 	return XDP_TX;
4348 }
4349 EXPORT_SYMBOL_GPL(xdp_master_redirect);
4350 
__xdp_do_redirect_xsk(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4351 static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri,
4352 					struct net_device *dev,
4353 					struct xdp_buff *xdp,
4354 					struct bpf_prog *xdp_prog)
4355 {
4356 	enum bpf_map_type map_type = ri->map_type;
4357 	void *fwd = ri->tgt_value;
4358 	u32 map_id = ri->map_id;
4359 	int err;
4360 
4361 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4362 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4363 
4364 	err = __xsk_map_redirect(fwd, xdp);
4365 	if (unlikely(err))
4366 		goto err;
4367 
4368 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4369 	return 0;
4370 err:
4371 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4372 	return err;
4373 }
4374 
__xdp_do_redirect_frame(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4375 static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
4376 						   struct net_device *dev,
4377 						   struct xdp_frame *xdpf,
4378 						   struct bpf_prog *xdp_prog)
4379 {
4380 	enum bpf_map_type map_type = ri->map_type;
4381 	void *fwd = ri->tgt_value;
4382 	u32 map_id = ri->map_id;
4383 	u32 flags = ri->flags;
4384 	struct bpf_map *map;
4385 	int err;
4386 
4387 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4388 	ri->flags = 0;
4389 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4390 
4391 	if (unlikely(!xdpf)) {
4392 		err = -EOVERFLOW;
4393 		goto err;
4394 	}
4395 
4396 	switch (map_type) {
4397 	case BPF_MAP_TYPE_DEVMAP:
4398 		fallthrough;
4399 	case BPF_MAP_TYPE_DEVMAP_HASH:
4400 		if (unlikely(flags & BPF_F_BROADCAST)) {
4401 			map = READ_ONCE(ri->map);
4402 
4403 			/* The map pointer is cleared when the map is being torn
4404 			 * down by bpf_clear_redirect_map()
4405 			 */
4406 			if (unlikely(!map)) {
4407 				err = -ENOENT;
4408 				break;
4409 			}
4410 
4411 			WRITE_ONCE(ri->map, NULL);
4412 			err = dev_map_enqueue_multi(xdpf, dev, map,
4413 						    flags & BPF_F_EXCLUDE_INGRESS);
4414 		} else {
4415 			err = dev_map_enqueue(fwd, xdpf, dev);
4416 		}
4417 		break;
4418 	case BPF_MAP_TYPE_CPUMAP:
4419 		err = cpu_map_enqueue(fwd, xdpf, dev);
4420 		break;
4421 	case BPF_MAP_TYPE_UNSPEC:
4422 		if (map_id == INT_MAX) {
4423 			fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4424 			if (unlikely(!fwd)) {
4425 				err = -EINVAL;
4426 				break;
4427 			}
4428 			err = dev_xdp_enqueue(fwd, xdpf, dev);
4429 			break;
4430 		}
4431 		fallthrough;
4432 	default:
4433 		err = -EBADRQC;
4434 	}
4435 
4436 	if (unlikely(err))
4437 		goto err;
4438 
4439 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4440 	return 0;
4441 err:
4442 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4443 	return err;
4444 }
4445 
xdp_do_redirect(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4446 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
4447 		    struct bpf_prog *xdp_prog)
4448 {
4449 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4450 	enum bpf_map_type map_type = ri->map_type;
4451 
4452 	if (map_type == BPF_MAP_TYPE_XSKMAP)
4453 		return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);
4454 
4455 	return __xdp_do_redirect_frame(ri, dev, xdp_convert_buff_to_frame(xdp),
4456 				       xdp_prog);
4457 }
4458 EXPORT_SYMBOL_GPL(xdp_do_redirect);
4459 
xdp_do_redirect_frame(struct net_device * dev,struct xdp_buff * xdp,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4460 int xdp_do_redirect_frame(struct net_device *dev, struct xdp_buff *xdp,
4461 			  struct xdp_frame *xdpf, struct bpf_prog *xdp_prog)
4462 {
4463 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4464 	enum bpf_map_type map_type = ri->map_type;
4465 
4466 	if (map_type == BPF_MAP_TYPE_XSKMAP)
4467 		return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);
4468 
4469 	return __xdp_do_redirect_frame(ri, dev, xdpf, xdp_prog);
4470 }
4471 EXPORT_SYMBOL_GPL(xdp_do_redirect_frame);
4472 
xdp_do_generic_redirect_map(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog,void * fwd,enum bpf_map_type map_type,u32 map_id,u32 flags)4473 static int xdp_do_generic_redirect_map(struct net_device *dev,
4474 				       struct sk_buff *skb,
4475 				       struct xdp_buff *xdp,
4476 				       struct bpf_prog *xdp_prog, void *fwd,
4477 				       enum bpf_map_type map_type, u32 map_id,
4478 				       u32 flags)
4479 {
4480 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4481 	struct bpf_map *map;
4482 	int err;
4483 
4484 	switch (map_type) {
4485 	case BPF_MAP_TYPE_DEVMAP:
4486 		fallthrough;
4487 	case BPF_MAP_TYPE_DEVMAP_HASH:
4488 		if (unlikely(flags & BPF_F_BROADCAST)) {
4489 			map = READ_ONCE(ri->map);
4490 
4491 			/* The map pointer is cleared when the map is being torn
4492 			 * down by bpf_clear_redirect_map()
4493 			 */
4494 			if (unlikely(!map)) {
4495 				err = -ENOENT;
4496 				break;
4497 			}
4498 
4499 			WRITE_ONCE(ri->map, NULL);
4500 			err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
4501 						     flags & BPF_F_EXCLUDE_INGRESS);
4502 		} else {
4503 			err = dev_map_generic_redirect(fwd, skb, xdp_prog);
4504 		}
4505 		if (unlikely(err))
4506 			goto err;
4507 		break;
4508 	case BPF_MAP_TYPE_XSKMAP:
4509 		err = xsk_generic_rcv(fwd, xdp);
4510 		if (err)
4511 			goto err;
4512 		consume_skb(skb);
4513 		break;
4514 	case BPF_MAP_TYPE_CPUMAP:
4515 		err = cpu_map_generic_redirect(fwd, skb);
4516 		if (unlikely(err))
4517 			goto err;
4518 		break;
4519 	default:
4520 		err = -EBADRQC;
4521 		goto err;
4522 	}
4523 
4524 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4525 	return 0;
4526 err:
4527 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4528 	return err;
4529 }
4530 
xdp_do_generic_redirect(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4531 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
4532 			    struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
4533 {
4534 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4535 	enum bpf_map_type map_type = ri->map_type;
4536 	void *fwd = ri->tgt_value;
4537 	u32 map_id = ri->map_id;
4538 	u32 flags = ri->flags;
4539 	int err;
4540 
4541 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4542 	ri->flags = 0;
4543 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4544 
4545 	if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
4546 		fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4547 		if (unlikely(!fwd)) {
4548 			err = -EINVAL;
4549 			goto err;
4550 		}
4551 
4552 		err = xdp_ok_fwd_dev(fwd, skb->len);
4553 		if (unlikely(err))
4554 			goto err;
4555 
4556 		skb->dev = fwd;
4557 		_trace_xdp_redirect(dev, xdp_prog, ri->tgt_index);
4558 		generic_xdp_tx(skb, xdp_prog);
4559 		return 0;
4560 	}
4561 
4562 	return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id, flags);
4563 err:
4564 	_trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
4565 	return err;
4566 }
4567 
BPF_CALL_2(bpf_xdp_redirect,u32,ifindex,u64,flags)4568 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
4569 {
4570 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4571 
4572 	if (unlikely(flags))
4573 		return XDP_ABORTED;
4574 
4575 	/* NB! Map type UNSPEC and map_id == INT_MAX (never generated
4576 	 * by map_idr) is used for ifindex based XDP redirect.
4577 	 */
4578 	ri->tgt_index = ifindex;
4579 	ri->map_id = INT_MAX;
4580 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4581 
4582 	return XDP_REDIRECT;
4583 }
4584 
4585 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
4586 	.func           = bpf_xdp_redirect,
4587 	.gpl_only       = false,
4588 	.ret_type       = RET_INTEGER,
4589 	.arg1_type      = ARG_ANYTHING,
4590 	.arg2_type      = ARG_ANYTHING,
4591 };
4592 
BPF_CALL_3(bpf_xdp_redirect_map,struct bpf_map *,map,u64,key,u64,flags)4593 BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u64, key,
4594 	   u64, flags)
4595 {
4596 	return map->ops->map_redirect(map, key, flags);
4597 }
4598 
4599 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
4600 	.func           = bpf_xdp_redirect_map,
4601 	.gpl_only       = false,
4602 	.ret_type       = RET_INTEGER,
4603 	.arg1_type      = ARG_CONST_MAP_PTR,
4604 	.arg2_type      = ARG_ANYTHING,
4605 	.arg3_type      = ARG_ANYTHING,
4606 };
4607 
bpf_skb_copy(void * dst_buff,const void * skb,unsigned long off,unsigned long len)4608 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
4609 				  unsigned long off, unsigned long len)
4610 {
4611 	void *ptr = skb_header_pointer(skb, off, len, dst_buff);
4612 
4613 	if (unlikely(!ptr))
4614 		return len;
4615 	if (ptr != dst_buff)
4616 		memcpy(dst_buff, ptr, len);
4617 
4618 	return 0;
4619 }
4620 
BPF_CALL_5(bpf_skb_event_output,struct sk_buff *,skb,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4621 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
4622 	   u64, flags, void *, meta, u64, meta_size)
4623 {
4624 	u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4625 
4626 	if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4627 		return -EINVAL;
4628 	if (unlikely(!skb || skb_size > skb->len))
4629 		return -EFAULT;
4630 
4631 	return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
4632 				bpf_skb_copy);
4633 }
4634 
4635 static const struct bpf_func_proto bpf_skb_event_output_proto = {
4636 	.func		= bpf_skb_event_output,
4637 	.gpl_only	= true,
4638 	.ret_type	= RET_INTEGER,
4639 	.arg1_type	= ARG_PTR_TO_CTX,
4640 	.arg2_type	= ARG_CONST_MAP_PTR,
4641 	.arg3_type	= ARG_ANYTHING,
4642 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4643 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4644 };
4645 
4646 BTF_ID_LIST_SINGLE(bpf_skb_output_btf_ids, struct, sk_buff)
4647 
4648 const struct bpf_func_proto bpf_skb_output_proto = {
4649 	.func		= bpf_skb_event_output,
4650 	.gpl_only	= true,
4651 	.ret_type	= RET_INTEGER,
4652 	.arg1_type	= ARG_PTR_TO_BTF_ID,
4653 	.arg1_btf_id	= &bpf_skb_output_btf_ids[0],
4654 	.arg2_type	= ARG_CONST_MAP_PTR,
4655 	.arg3_type	= ARG_ANYTHING,
4656 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4657 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4658 };
4659 
bpf_tunnel_key_af(u64 flags)4660 static unsigned short bpf_tunnel_key_af(u64 flags)
4661 {
4662 	return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
4663 }
4664 
BPF_CALL_4(bpf_skb_get_tunnel_key,struct sk_buff *,skb,struct bpf_tunnel_key *,to,u32,size,u64,flags)4665 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
4666 	   u32, size, u64, flags)
4667 {
4668 	const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4669 	u8 compat[sizeof(struct bpf_tunnel_key)];
4670 	void *to_orig = to;
4671 	int err;
4672 
4673 	if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6 |
4674 					 BPF_F_TUNINFO_FLAGS)))) {
4675 		err = -EINVAL;
4676 		goto err_clear;
4677 	}
4678 	if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
4679 		err = -EPROTO;
4680 		goto err_clear;
4681 	}
4682 	if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4683 		err = -EINVAL;
4684 		switch (size) {
4685 		case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4686 		case offsetof(struct bpf_tunnel_key, tunnel_label):
4687 		case offsetof(struct bpf_tunnel_key, tunnel_ext):
4688 			goto set_compat;
4689 		case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4690 			/* Fixup deprecated structure layouts here, so we have
4691 			 * a common path later on.
4692 			 */
4693 			if (ip_tunnel_info_af(info) != AF_INET)
4694 				goto err_clear;
4695 set_compat:
4696 			to = (struct bpf_tunnel_key *)compat;
4697 			break;
4698 		default:
4699 			goto err_clear;
4700 		}
4701 	}
4702 
4703 	to->tunnel_id = be64_to_cpu(info->key.tun_id);
4704 	to->tunnel_tos = info->key.tos;
4705 	to->tunnel_ttl = info->key.ttl;
4706 	if (flags & BPF_F_TUNINFO_FLAGS)
4707 		to->tunnel_flags = info->key.tun_flags;
4708 	else
4709 		to->tunnel_ext = 0;
4710 
4711 	if (flags & BPF_F_TUNINFO_IPV6) {
4712 		memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
4713 		       sizeof(to->remote_ipv6));
4714 		memcpy(to->local_ipv6, &info->key.u.ipv6.dst,
4715 		       sizeof(to->local_ipv6));
4716 		to->tunnel_label = be32_to_cpu(info->key.label);
4717 	} else {
4718 		to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
4719 		memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
4720 		to->local_ipv4 = be32_to_cpu(info->key.u.ipv4.dst);
4721 		memset(&to->local_ipv6[1], 0, sizeof(__u32) * 3);
4722 		to->tunnel_label = 0;
4723 	}
4724 
4725 	if (unlikely(size != sizeof(struct bpf_tunnel_key)))
4726 		memcpy(to_orig, to, size);
4727 
4728 	return 0;
4729 err_clear:
4730 	memset(to_orig, 0, size);
4731 	return err;
4732 }
4733 
4734 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
4735 	.func		= bpf_skb_get_tunnel_key,
4736 	.gpl_only	= false,
4737 	.ret_type	= RET_INTEGER,
4738 	.arg1_type	= ARG_PTR_TO_CTX,
4739 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
4740 	.arg3_type	= ARG_CONST_SIZE,
4741 	.arg4_type	= ARG_ANYTHING,
4742 };
4743 
BPF_CALL_3(bpf_skb_get_tunnel_opt,struct sk_buff *,skb,u8 *,to,u32,size)4744 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
4745 {
4746 	const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4747 	int err;
4748 
4749 	if (unlikely(!info ||
4750 		     !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
4751 		err = -ENOENT;
4752 		goto err_clear;
4753 	}
4754 	if (unlikely(size < info->options_len)) {
4755 		err = -ENOMEM;
4756 		goto err_clear;
4757 	}
4758 
4759 	ip_tunnel_info_opts_get(to, info);
4760 	if (size > info->options_len)
4761 		memset(to + info->options_len, 0, size - info->options_len);
4762 
4763 	return info->options_len;
4764 err_clear:
4765 	memset(to, 0, size);
4766 	return err;
4767 }
4768 
4769 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
4770 	.func		= bpf_skb_get_tunnel_opt,
4771 	.gpl_only	= false,
4772 	.ret_type	= RET_INTEGER,
4773 	.arg1_type	= ARG_PTR_TO_CTX,
4774 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
4775 	.arg3_type	= ARG_CONST_SIZE,
4776 };
4777 
4778 static struct metadata_dst __percpu *md_dst;
4779 
BPF_CALL_4(bpf_skb_set_tunnel_key,struct sk_buff *,skb,const struct bpf_tunnel_key *,from,u32,size,u64,flags)4780 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
4781 	   const struct bpf_tunnel_key *, from, u32, size, u64, flags)
4782 {
4783 	struct metadata_dst *md = this_cpu_ptr(md_dst);
4784 	u8 compat[sizeof(struct bpf_tunnel_key)];
4785 	struct ip_tunnel_info *info;
4786 
4787 	if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
4788 			       BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER |
4789 			       BPF_F_NO_TUNNEL_KEY)))
4790 		return -EINVAL;
4791 	if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4792 		switch (size) {
4793 		case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4794 		case offsetof(struct bpf_tunnel_key, tunnel_label):
4795 		case offsetof(struct bpf_tunnel_key, tunnel_ext):
4796 		case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4797 			/* Fixup deprecated structure layouts here, so we have
4798 			 * a common path later on.
4799 			 */
4800 			memcpy(compat, from, size);
4801 			memset(compat + size, 0, sizeof(compat) - size);
4802 			from = (const struct bpf_tunnel_key *) compat;
4803 			break;
4804 		default:
4805 			return -EINVAL;
4806 		}
4807 	}
4808 	if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
4809 		     from->tunnel_ext))
4810 		return -EINVAL;
4811 
4812 	skb_dst_drop(skb);
4813 	dst_hold((struct dst_entry *) md);
4814 	skb_dst_set(skb, (struct dst_entry *) md);
4815 
4816 	info = &md->u.tun_info;
4817 	memset(info, 0, sizeof(*info));
4818 	info->mode = IP_TUNNEL_INFO_TX;
4819 
4820 	info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
4821 	if (flags & BPF_F_DONT_FRAGMENT)
4822 		info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
4823 	if (flags & BPF_F_ZERO_CSUM_TX)
4824 		info->key.tun_flags &= ~TUNNEL_CSUM;
4825 	if (flags & BPF_F_SEQ_NUMBER)
4826 		info->key.tun_flags |= TUNNEL_SEQ;
4827 	if (flags & BPF_F_NO_TUNNEL_KEY)
4828 		info->key.tun_flags &= ~TUNNEL_KEY;
4829 
4830 	info->key.tun_id = cpu_to_be64(from->tunnel_id);
4831 	info->key.tos = from->tunnel_tos;
4832 	info->key.ttl = from->tunnel_ttl;
4833 
4834 	if (flags & BPF_F_TUNINFO_IPV6) {
4835 		info->mode |= IP_TUNNEL_INFO_IPV6;
4836 		memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
4837 		       sizeof(from->remote_ipv6));
4838 		memcpy(&info->key.u.ipv6.src, from->local_ipv6,
4839 		       sizeof(from->local_ipv6));
4840 		info->key.label = cpu_to_be32(from->tunnel_label) &
4841 				  IPV6_FLOWLABEL_MASK;
4842 	} else {
4843 		info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
4844 		info->key.u.ipv4.src = cpu_to_be32(from->local_ipv4);
4845 		info->key.flow_flags = FLOWI_FLAG_ANYSRC;
4846 	}
4847 
4848 	return 0;
4849 }
4850 
4851 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
4852 	.func		= bpf_skb_set_tunnel_key,
4853 	.gpl_only	= false,
4854 	.ret_type	= RET_INTEGER,
4855 	.arg1_type	= ARG_PTR_TO_CTX,
4856 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4857 	.arg3_type	= ARG_CONST_SIZE,
4858 	.arg4_type	= ARG_ANYTHING,
4859 };
4860 
BPF_CALL_3(bpf_skb_set_tunnel_opt,struct sk_buff *,skb,const u8 *,from,u32,size)4861 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
4862 	   const u8 *, from, u32, size)
4863 {
4864 	struct ip_tunnel_info *info = skb_tunnel_info(skb);
4865 	const struct metadata_dst *md = this_cpu_ptr(md_dst);
4866 
4867 	if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
4868 		return -EINVAL;
4869 	if (unlikely(size > IP_TUNNEL_OPTS_MAX))
4870 		return -ENOMEM;
4871 
4872 	ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT);
4873 
4874 	return 0;
4875 }
4876 
4877 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
4878 	.func		= bpf_skb_set_tunnel_opt,
4879 	.gpl_only	= false,
4880 	.ret_type	= RET_INTEGER,
4881 	.arg1_type	= ARG_PTR_TO_CTX,
4882 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4883 	.arg3_type	= ARG_CONST_SIZE,
4884 };
4885 
4886 static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)4887 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
4888 {
4889 	if (!md_dst) {
4890 		struct metadata_dst __percpu *tmp;
4891 
4892 		tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
4893 						METADATA_IP_TUNNEL,
4894 						GFP_KERNEL);
4895 		if (!tmp)
4896 			return NULL;
4897 		if (cmpxchg(&md_dst, NULL, tmp))
4898 			metadata_dst_free_percpu(tmp);
4899 	}
4900 
4901 	switch (which) {
4902 	case BPF_FUNC_skb_set_tunnel_key:
4903 		return &bpf_skb_set_tunnel_key_proto;
4904 	case BPF_FUNC_skb_set_tunnel_opt:
4905 		return &bpf_skb_set_tunnel_opt_proto;
4906 	default:
4907 		return NULL;
4908 	}
4909 }
4910 
BPF_CALL_3(bpf_skb_under_cgroup,struct sk_buff *,skb,struct bpf_map *,map,u32,idx)4911 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
4912 	   u32, idx)
4913 {
4914 	struct bpf_array *array = container_of(map, struct bpf_array, map);
4915 	struct cgroup *cgrp;
4916 	struct sock *sk;
4917 
4918 	sk = skb_to_full_sk(skb);
4919 	if (!sk || !sk_fullsock(sk))
4920 		return -ENOENT;
4921 	if (unlikely(idx >= array->map.max_entries))
4922 		return -E2BIG;
4923 
4924 	cgrp = READ_ONCE(array->ptrs[idx]);
4925 	if (unlikely(!cgrp))
4926 		return -EAGAIN;
4927 
4928 	return sk_under_cgroup_hierarchy(sk, cgrp);
4929 }
4930 
4931 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
4932 	.func		= bpf_skb_under_cgroup,
4933 	.gpl_only	= false,
4934 	.ret_type	= RET_INTEGER,
4935 	.arg1_type	= ARG_PTR_TO_CTX,
4936 	.arg2_type	= ARG_CONST_MAP_PTR,
4937 	.arg3_type	= ARG_ANYTHING,
4938 };
4939 
4940 #ifdef CONFIG_SOCK_CGROUP_DATA
__bpf_sk_cgroup_id(struct sock * sk)4941 static inline u64 __bpf_sk_cgroup_id(struct sock *sk)
4942 {
4943 	struct cgroup *cgrp;
4944 
4945 	sk = sk_to_full_sk(sk);
4946 	if (!sk || !sk_fullsock(sk))
4947 		return 0;
4948 
4949 	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4950 	return cgroup_id(cgrp);
4951 }
4952 
BPF_CALL_1(bpf_skb_cgroup_id,const struct sk_buff *,skb)4953 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
4954 {
4955 	return __bpf_sk_cgroup_id(skb->sk);
4956 }
4957 
4958 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
4959 	.func           = bpf_skb_cgroup_id,
4960 	.gpl_only       = false,
4961 	.ret_type       = RET_INTEGER,
4962 	.arg1_type      = ARG_PTR_TO_CTX,
4963 };
4964 
__bpf_sk_ancestor_cgroup_id(struct sock * sk,int ancestor_level)4965 static inline u64 __bpf_sk_ancestor_cgroup_id(struct sock *sk,
4966 					      int ancestor_level)
4967 {
4968 	struct cgroup *ancestor;
4969 	struct cgroup *cgrp;
4970 
4971 	sk = sk_to_full_sk(sk);
4972 	if (!sk || !sk_fullsock(sk))
4973 		return 0;
4974 
4975 	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4976 	ancestor = cgroup_ancestor(cgrp, ancestor_level);
4977 	if (!ancestor)
4978 		return 0;
4979 
4980 	return cgroup_id(ancestor);
4981 }
4982 
BPF_CALL_2(bpf_skb_ancestor_cgroup_id,const struct sk_buff *,skb,int,ancestor_level)4983 BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int,
4984 	   ancestor_level)
4985 {
4986 	return __bpf_sk_ancestor_cgroup_id(skb->sk, ancestor_level);
4987 }
4988 
4989 static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = {
4990 	.func           = bpf_skb_ancestor_cgroup_id,
4991 	.gpl_only       = false,
4992 	.ret_type       = RET_INTEGER,
4993 	.arg1_type      = ARG_PTR_TO_CTX,
4994 	.arg2_type      = ARG_ANYTHING,
4995 };
4996 
BPF_CALL_1(bpf_sk_cgroup_id,struct sock *,sk)4997 BPF_CALL_1(bpf_sk_cgroup_id, struct sock *, sk)
4998 {
4999 	return __bpf_sk_cgroup_id(sk);
5000 }
5001 
5002 static const struct bpf_func_proto bpf_sk_cgroup_id_proto = {
5003 	.func           = bpf_sk_cgroup_id,
5004 	.gpl_only       = false,
5005 	.ret_type       = RET_INTEGER,
5006 	.arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5007 };
5008 
BPF_CALL_2(bpf_sk_ancestor_cgroup_id,struct sock *,sk,int,ancestor_level)5009 BPF_CALL_2(bpf_sk_ancestor_cgroup_id, struct sock *, sk, int, ancestor_level)
5010 {
5011 	return __bpf_sk_ancestor_cgroup_id(sk, ancestor_level);
5012 }
5013 
5014 static const struct bpf_func_proto bpf_sk_ancestor_cgroup_id_proto = {
5015 	.func           = bpf_sk_ancestor_cgroup_id,
5016 	.gpl_only       = false,
5017 	.ret_type       = RET_INTEGER,
5018 	.arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5019 	.arg2_type      = ARG_ANYTHING,
5020 };
5021 #endif
5022 
bpf_xdp_copy(void * dst,const void * ctx,unsigned long off,unsigned long len)5023 static unsigned long bpf_xdp_copy(void *dst, const void *ctx,
5024 				  unsigned long off, unsigned long len)
5025 {
5026 	struct xdp_buff *xdp = (struct xdp_buff *)ctx;
5027 
5028 	bpf_xdp_copy_buf(xdp, off, dst, len, false);
5029 	return 0;
5030 }
5031 
BPF_CALL_5(bpf_xdp_event_output,struct xdp_buff *,xdp,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)5032 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
5033 	   u64, flags, void *, meta, u64, meta_size)
5034 {
5035 	u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
5036 
5037 	if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
5038 		return -EINVAL;
5039 
5040 	if (unlikely(!xdp || xdp_size > xdp_get_buff_len(xdp)))
5041 		return -EFAULT;
5042 
5043 	return bpf_event_output(map, flags, meta, meta_size, xdp,
5044 				xdp_size, bpf_xdp_copy);
5045 }
5046 
5047 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
5048 	.func		= bpf_xdp_event_output,
5049 	.gpl_only	= true,
5050 	.ret_type	= RET_INTEGER,
5051 	.arg1_type	= ARG_PTR_TO_CTX,
5052 	.arg2_type	= ARG_CONST_MAP_PTR,
5053 	.arg3_type	= ARG_ANYTHING,
5054 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5055 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
5056 };
5057 
5058 BTF_ID_LIST_SINGLE(bpf_xdp_output_btf_ids, struct, xdp_buff)
5059 
5060 const struct bpf_func_proto bpf_xdp_output_proto = {
5061 	.func		= bpf_xdp_event_output,
5062 	.gpl_only	= true,
5063 	.ret_type	= RET_INTEGER,
5064 	.arg1_type	= ARG_PTR_TO_BTF_ID,
5065 	.arg1_btf_id	= &bpf_xdp_output_btf_ids[0],
5066 	.arg2_type	= ARG_CONST_MAP_PTR,
5067 	.arg3_type	= ARG_ANYTHING,
5068 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5069 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
5070 };
5071 
BPF_CALL_1(bpf_get_socket_cookie,struct sk_buff *,skb)5072 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
5073 {
5074 	return skb->sk ? __sock_gen_cookie(skb->sk) : 0;
5075 }
5076 
5077 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
5078 	.func           = bpf_get_socket_cookie,
5079 	.gpl_only       = false,
5080 	.ret_type       = RET_INTEGER,
5081 	.arg1_type      = ARG_PTR_TO_CTX,
5082 };
5083 
BPF_CALL_1(bpf_get_socket_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)5084 BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
5085 {
5086 	return __sock_gen_cookie(ctx->sk);
5087 }
5088 
5089 static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
5090 	.func		= bpf_get_socket_cookie_sock_addr,
5091 	.gpl_only	= false,
5092 	.ret_type	= RET_INTEGER,
5093 	.arg1_type	= ARG_PTR_TO_CTX,
5094 };
5095 
BPF_CALL_1(bpf_get_socket_cookie_sock,struct sock *,ctx)5096 BPF_CALL_1(bpf_get_socket_cookie_sock, struct sock *, ctx)
5097 {
5098 	return __sock_gen_cookie(ctx);
5099 }
5100 
5101 static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
5102 	.func		= bpf_get_socket_cookie_sock,
5103 	.gpl_only	= false,
5104 	.ret_type	= RET_INTEGER,
5105 	.arg1_type	= ARG_PTR_TO_CTX,
5106 };
5107 
BPF_CALL_1(bpf_get_socket_ptr_cookie,struct sock *,sk)5108 BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
5109 {
5110 	return sk ? sock_gen_cookie(sk) : 0;
5111 }
5112 
5113 const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
5114 	.func		= bpf_get_socket_ptr_cookie,
5115 	.gpl_only	= false,
5116 	.ret_type	= RET_INTEGER,
5117 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON | PTR_MAYBE_NULL,
5118 };
5119 
BPF_CALL_1(bpf_get_socket_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)5120 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
5121 {
5122 	return __sock_gen_cookie(ctx->sk);
5123 }
5124 
5125 static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
5126 	.func		= bpf_get_socket_cookie_sock_ops,
5127 	.gpl_only	= false,
5128 	.ret_type	= RET_INTEGER,
5129 	.arg1_type	= ARG_PTR_TO_CTX,
5130 };
5131 
__bpf_get_netns_cookie(struct sock * sk)5132 static u64 __bpf_get_netns_cookie(struct sock *sk)
5133 {
5134 	const struct net *net = sk ? sock_net(sk) : &init_net;
5135 
5136 	return net->net_cookie;
5137 }
5138 
BPF_CALL_1(bpf_get_netns_cookie_sock,struct sock *,ctx)5139 BPF_CALL_1(bpf_get_netns_cookie_sock, struct sock *, ctx)
5140 {
5141 	return __bpf_get_netns_cookie(ctx);
5142 }
5143 
5144 static const struct bpf_func_proto bpf_get_netns_cookie_sock_proto = {
5145 	.func		= bpf_get_netns_cookie_sock,
5146 	.gpl_only	= false,
5147 	.ret_type	= RET_INTEGER,
5148 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5149 };
5150 
BPF_CALL_1(bpf_get_netns_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)5151 BPF_CALL_1(bpf_get_netns_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
5152 {
5153 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
5154 }
5155 
5156 static const struct bpf_func_proto bpf_get_netns_cookie_sock_addr_proto = {
5157 	.func		= bpf_get_netns_cookie_sock_addr,
5158 	.gpl_only	= false,
5159 	.ret_type	= RET_INTEGER,
5160 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5161 };
5162 
BPF_CALL_1(bpf_get_netns_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)5163 BPF_CALL_1(bpf_get_netns_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
5164 {
5165 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
5166 }
5167 
5168 static const struct bpf_func_proto bpf_get_netns_cookie_sock_ops_proto = {
5169 	.func		= bpf_get_netns_cookie_sock_ops,
5170 	.gpl_only	= false,
5171 	.ret_type	= RET_INTEGER,
5172 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5173 };
5174 
BPF_CALL_1(bpf_get_netns_cookie_sk_msg,struct sk_msg *,ctx)5175 BPF_CALL_1(bpf_get_netns_cookie_sk_msg, struct sk_msg *, ctx)
5176 {
5177 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
5178 }
5179 
5180 static const struct bpf_func_proto bpf_get_netns_cookie_sk_msg_proto = {
5181 	.func		= bpf_get_netns_cookie_sk_msg,
5182 	.gpl_only	= false,
5183 	.ret_type	= RET_INTEGER,
5184 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5185 };
5186 
BPF_CALL_1(bpf_get_socket_uid,struct sk_buff *,skb)5187 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
5188 {
5189 	struct sock *sk = sk_to_full_sk(skb->sk);
5190 	kuid_t kuid;
5191 
5192 	if (!sk || !sk_fullsock(sk))
5193 		return overflowuid;
5194 	kuid = sock_net_uid(sock_net(sk), sk);
5195 	return from_kuid_munged(sock_net(sk)->user_ns, kuid);
5196 }
5197 
5198 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
5199 	.func           = bpf_get_socket_uid,
5200 	.gpl_only       = false,
5201 	.ret_type       = RET_INTEGER,
5202 	.arg1_type      = ARG_PTR_TO_CTX,
5203 };
5204 
sol_socket_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5205 static int sol_socket_sockopt(struct sock *sk, int optname,
5206 			      char *optval, int *optlen,
5207 			      bool getopt)
5208 {
5209 	switch (optname) {
5210 	case SO_REUSEADDR:
5211 	case SO_SNDBUF:
5212 	case SO_RCVBUF:
5213 	case SO_KEEPALIVE:
5214 	case SO_PRIORITY:
5215 	case SO_REUSEPORT:
5216 	case SO_RCVLOWAT:
5217 	case SO_MARK:
5218 	case SO_MAX_PACING_RATE:
5219 	case SO_BINDTOIFINDEX:
5220 	case SO_TXREHASH:
5221 		if (*optlen != sizeof(int))
5222 			return -EINVAL;
5223 		break;
5224 	case SO_BINDTODEVICE:
5225 		break;
5226 	default:
5227 		return -EINVAL;
5228 	}
5229 
5230 	if (getopt) {
5231 		if (optname == SO_BINDTODEVICE)
5232 			return -EINVAL;
5233 		return sk_getsockopt(sk, SOL_SOCKET, optname,
5234 				     KERNEL_SOCKPTR(optval),
5235 				     KERNEL_SOCKPTR(optlen));
5236 	}
5237 
5238 	return sk_setsockopt(sk, SOL_SOCKET, optname,
5239 			     KERNEL_SOCKPTR(optval), *optlen);
5240 }
5241 
bpf_sol_tcp_setsockopt(struct sock * sk,int optname,char * optval,int optlen)5242 static int bpf_sol_tcp_setsockopt(struct sock *sk, int optname,
5243 				  char *optval, int optlen)
5244 {
5245 	struct tcp_sock *tp = tcp_sk(sk);
5246 	unsigned long timeout;
5247 	int val;
5248 
5249 	if (optlen != sizeof(int))
5250 		return -EINVAL;
5251 
5252 	val = *(int *)optval;
5253 
5254 	/* Only some options are supported */
5255 	switch (optname) {
5256 	case TCP_BPF_IW:
5257 		if (val <= 0 || tp->data_segs_out > tp->syn_data)
5258 			return -EINVAL;
5259 		tcp_snd_cwnd_set(tp, val);
5260 		break;
5261 	case TCP_BPF_SNDCWND_CLAMP:
5262 		if (val <= 0)
5263 			return -EINVAL;
5264 		tp->snd_cwnd_clamp = val;
5265 		tp->snd_ssthresh = val;
5266 		break;
5267 	case TCP_BPF_DELACK_MAX:
5268 		timeout = usecs_to_jiffies(val);
5269 		if (timeout > TCP_DELACK_MAX ||
5270 		    timeout < TCP_TIMEOUT_MIN)
5271 			return -EINVAL;
5272 		inet_csk(sk)->icsk_delack_max = timeout;
5273 		break;
5274 	case TCP_BPF_RTO_MIN:
5275 		timeout = usecs_to_jiffies(val);
5276 		if (timeout > TCP_RTO_MIN ||
5277 		    timeout < TCP_TIMEOUT_MIN)
5278 			return -EINVAL;
5279 		inet_csk(sk)->icsk_rto_min = timeout;
5280 		break;
5281 	default:
5282 		return -EINVAL;
5283 	}
5284 
5285 	return 0;
5286 }
5287 
sol_tcp_sockopt_congestion(struct sock * sk,char * optval,int * optlen,bool getopt)5288 static int sol_tcp_sockopt_congestion(struct sock *sk, char *optval,
5289 				      int *optlen, bool getopt)
5290 {
5291 	struct tcp_sock *tp;
5292 	int ret;
5293 
5294 	if (*optlen < 2)
5295 		return -EINVAL;
5296 
5297 	if (getopt) {
5298 		if (!inet_csk(sk)->icsk_ca_ops)
5299 			return -EINVAL;
5300 		/* BPF expects NULL-terminated tcp-cc string */
5301 		optval[--(*optlen)] = '\0';
5302 		return do_tcp_getsockopt(sk, SOL_TCP, TCP_CONGESTION,
5303 					 KERNEL_SOCKPTR(optval),
5304 					 KERNEL_SOCKPTR(optlen));
5305 	}
5306 
5307 	/* "cdg" is the only cc that alloc a ptr
5308 	 * in inet_csk_ca area.  The bpf-tcp-cc may
5309 	 * overwrite this ptr after switching to cdg.
5310 	 */
5311 	if (*optlen >= sizeof("cdg") - 1 && !strncmp("cdg", optval, *optlen))
5312 		return -ENOTSUPP;
5313 
5314 	/* It stops this looping
5315 	 *
5316 	 * .init => bpf_setsockopt(tcp_cc) => .init =>
5317 	 * bpf_setsockopt(tcp_cc)" => .init => ....
5318 	 *
5319 	 * The second bpf_setsockopt(tcp_cc) is not allowed
5320 	 * in order to break the loop when both .init
5321 	 * are the same bpf prog.
5322 	 *
5323 	 * This applies even the second bpf_setsockopt(tcp_cc)
5324 	 * does not cause a loop.  This limits only the first
5325 	 * '.init' can call bpf_setsockopt(TCP_CONGESTION) to
5326 	 * pick a fallback cc (eg. peer does not support ECN)
5327 	 * and the second '.init' cannot fallback to
5328 	 * another.
5329 	 */
5330 	tp = tcp_sk(sk);
5331 	if (tp->bpf_chg_cc_inprogress)
5332 		return -EBUSY;
5333 
5334 	tp->bpf_chg_cc_inprogress = 1;
5335 	ret = do_tcp_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
5336 				KERNEL_SOCKPTR(optval), *optlen);
5337 	tp->bpf_chg_cc_inprogress = 0;
5338 	return ret;
5339 }
5340 
sol_tcp_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5341 static int sol_tcp_sockopt(struct sock *sk, int optname,
5342 			   char *optval, int *optlen,
5343 			   bool getopt)
5344 {
5345 	if (sk->sk_protocol != IPPROTO_TCP)
5346 		return -EINVAL;
5347 
5348 	switch (optname) {
5349 	case TCP_NODELAY:
5350 	case TCP_MAXSEG:
5351 	case TCP_KEEPIDLE:
5352 	case TCP_KEEPINTVL:
5353 	case TCP_KEEPCNT:
5354 	case TCP_SYNCNT:
5355 	case TCP_WINDOW_CLAMP:
5356 	case TCP_THIN_LINEAR_TIMEOUTS:
5357 	case TCP_USER_TIMEOUT:
5358 	case TCP_NOTSENT_LOWAT:
5359 	case TCP_SAVE_SYN:
5360 		if (*optlen != sizeof(int))
5361 			return -EINVAL;
5362 		break;
5363 	case TCP_CONGESTION:
5364 		return sol_tcp_sockopt_congestion(sk, optval, optlen, getopt);
5365 	case TCP_SAVED_SYN:
5366 		if (*optlen < 1)
5367 			return -EINVAL;
5368 		break;
5369 	default:
5370 		if (getopt)
5371 			return -EINVAL;
5372 		return bpf_sol_tcp_setsockopt(sk, optname, optval, *optlen);
5373 	}
5374 
5375 	if (getopt) {
5376 		if (optname == TCP_SAVED_SYN) {
5377 			struct tcp_sock *tp = tcp_sk(sk);
5378 
5379 			if (!tp->saved_syn ||
5380 			    *optlen > tcp_saved_syn_len(tp->saved_syn))
5381 				return -EINVAL;
5382 			memcpy(optval, tp->saved_syn->data, *optlen);
5383 			/* It cannot free tp->saved_syn here because it
5384 			 * does not know if the user space still needs it.
5385 			 */
5386 			return 0;
5387 		}
5388 
5389 		return do_tcp_getsockopt(sk, SOL_TCP, optname,
5390 					 KERNEL_SOCKPTR(optval),
5391 					 KERNEL_SOCKPTR(optlen));
5392 	}
5393 
5394 	return do_tcp_setsockopt(sk, SOL_TCP, optname,
5395 				 KERNEL_SOCKPTR(optval), *optlen);
5396 }
5397 
sol_ip_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5398 static int sol_ip_sockopt(struct sock *sk, int optname,
5399 			  char *optval, int *optlen,
5400 			  bool getopt)
5401 {
5402 	if (sk->sk_family != AF_INET)
5403 		return -EINVAL;
5404 
5405 	switch (optname) {
5406 	case IP_TOS:
5407 		if (*optlen != sizeof(int))
5408 			return -EINVAL;
5409 		break;
5410 	default:
5411 		return -EINVAL;
5412 	}
5413 
5414 	if (getopt)
5415 		return do_ip_getsockopt(sk, SOL_IP, optname,
5416 					KERNEL_SOCKPTR(optval),
5417 					KERNEL_SOCKPTR(optlen));
5418 
5419 	return do_ip_setsockopt(sk, SOL_IP, optname,
5420 				KERNEL_SOCKPTR(optval), *optlen);
5421 }
5422 
sol_ipv6_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5423 static int sol_ipv6_sockopt(struct sock *sk, int optname,
5424 			    char *optval, int *optlen,
5425 			    bool getopt)
5426 {
5427 	if (sk->sk_family != AF_INET6)
5428 		return -EINVAL;
5429 
5430 	switch (optname) {
5431 	case IPV6_TCLASS:
5432 	case IPV6_AUTOFLOWLABEL:
5433 		if (*optlen != sizeof(int))
5434 			return -EINVAL;
5435 		break;
5436 	default:
5437 		return -EINVAL;
5438 	}
5439 
5440 	if (getopt)
5441 		return ipv6_bpf_stub->ipv6_getsockopt(sk, SOL_IPV6, optname,
5442 						      KERNEL_SOCKPTR(optval),
5443 						      KERNEL_SOCKPTR(optlen));
5444 
5445 	return ipv6_bpf_stub->ipv6_setsockopt(sk, SOL_IPV6, optname,
5446 					      KERNEL_SOCKPTR(optval), *optlen);
5447 }
5448 
__bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5449 static int __bpf_setsockopt(struct sock *sk, int level, int optname,
5450 			    char *optval, int optlen)
5451 {
5452 	if (!sk_fullsock(sk))
5453 		return -EINVAL;
5454 
5455 	if (level == SOL_SOCKET)
5456 		return sol_socket_sockopt(sk, optname, optval, &optlen, false);
5457 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
5458 		return sol_ip_sockopt(sk, optname, optval, &optlen, false);
5459 	else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
5460 		return sol_ipv6_sockopt(sk, optname, optval, &optlen, false);
5461 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
5462 		return sol_tcp_sockopt(sk, optname, optval, &optlen, false);
5463 
5464 	return -EINVAL;
5465 }
5466 
_bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5467 static int _bpf_setsockopt(struct sock *sk, int level, int optname,
5468 			   char *optval, int optlen)
5469 {
5470 	if (sk_fullsock(sk))
5471 		sock_owned_by_me(sk);
5472 	return __bpf_setsockopt(sk, level, optname, optval, optlen);
5473 }
5474 
__bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5475 static int __bpf_getsockopt(struct sock *sk, int level, int optname,
5476 			    char *optval, int optlen)
5477 {
5478 	int err, saved_optlen = optlen;
5479 
5480 	if (!sk_fullsock(sk)) {
5481 		err = -EINVAL;
5482 		goto done;
5483 	}
5484 
5485 	if (level == SOL_SOCKET)
5486 		err = sol_socket_sockopt(sk, optname, optval, &optlen, true);
5487 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
5488 		err = sol_tcp_sockopt(sk, optname, optval, &optlen, true);
5489 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
5490 		err = sol_ip_sockopt(sk, optname, optval, &optlen, true);
5491 	else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
5492 		err = sol_ipv6_sockopt(sk, optname, optval, &optlen, true);
5493 	else
5494 		err = -EINVAL;
5495 
5496 done:
5497 	if (err)
5498 		optlen = 0;
5499 	if (optlen < saved_optlen)
5500 		memset(optval + optlen, 0, saved_optlen - optlen);
5501 	return err;
5502 }
5503 
_bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5504 static int _bpf_getsockopt(struct sock *sk, int level, int optname,
5505 			   char *optval, int optlen)
5506 {
5507 	if (sk_fullsock(sk))
5508 		sock_owned_by_me(sk);
5509 	return __bpf_getsockopt(sk, level, optname, optval, optlen);
5510 }
5511 
BPF_CALL_5(bpf_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5512 BPF_CALL_5(bpf_sk_setsockopt, struct sock *, sk, int, level,
5513 	   int, optname, char *, optval, int, optlen)
5514 {
5515 	return _bpf_setsockopt(sk, level, optname, optval, optlen);
5516 }
5517 
5518 const struct bpf_func_proto bpf_sk_setsockopt_proto = {
5519 	.func		= bpf_sk_setsockopt,
5520 	.gpl_only	= false,
5521 	.ret_type	= RET_INTEGER,
5522 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5523 	.arg2_type	= ARG_ANYTHING,
5524 	.arg3_type	= ARG_ANYTHING,
5525 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5526 	.arg5_type	= ARG_CONST_SIZE,
5527 };
5528 
BPF_CALL_5(bpf_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5529 BPF_CALL_5(bpf_sk_getsockopt, struct sock *, sk, int, level,
5530 	   int, optname, char *, optval, int, optlen)
5531 {
5532 	return _bpf_getsockopt(sk, level, optname, optval, optlen);
5533 }
5534 
5535 const struct bpf_func_proto bpf_sk_getsockopt_proto = {
5536 	.func		= bpf_sk_getsockopt,
5537 	.gpl_only	= false,
5538 	.ret_type	= RET_INTEGER,
5539 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5540 	.arg2_type	= ARG_ANYTHING,
5541 	.arg3_type	= ARG_ANYTHING,
5542 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5543 	.arg5_type	= ARG_CONST_SIZE,
5544 };
5545 
BPF_CALL_5(bpf_unlocked_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5546 BPF_CALL_5(bpf_unlocked_sk_setsockopt, struct sock *, sk, int, level,
5547 	   int, optname, char *, optval, int, optlen)
5548 {
5549 	return __bpf_setsockopt(sk, level, optname, optval, optlen);
5550 }
5551 
5552 const struct bpf_func_proto bpf_unlocked_sk_setsockopt_proto = {
5553 	.func		= bpf_unlocked_sk_setsockopt,
5554 	.gpl_only	= false,
5555 	.ret_type	= RET_INTEGER,
5556 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5557 	.arg2_type	= ARG_ANYTHING,
5558 	.arg3_type	= ARG_ANYTHING,
5559 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5560 	.arg5_type	= ARG_CONST_SIZE,
5561 };
5562 
BPF_CALL_5(bpf_unlocked_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5563 BPF_CALL_5(bpf_unlocked_sk_getsockopt, struct sock *, sk, int, level,
5564 	   int, optname, char *, optval, int, optlen)
5565 {
5566 	return __bpf_getsockopt(sk, level, optname, optval, optlen);
5567 }
5568 
5569 const struct bpf_func_proto bpf_unlocked_sk_getsockopt_proto = {
5570 	.func		= bpf_unlocked_sk_getsockopt,
5571 	.gpl_only	= false,
5572 	.ret_type	= RET_INTEGER,
5573 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5574 	.arg2_type	= ARG_ANYTHING,
5575 	.arg3_type	= ARG_ANYTHING,
5576 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5577 	.arg5_type	= ARG_CONST_SIZE,
5578 };
5579 
BPF_CALL_5(bpf_sock_addr_setsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5580 BPF_CALL_5(bpf_sock_addr_setsockopt, struct bpf_sock_addr_kern *, ctx,
5581 	   int, level, int, optname, char *, optval, int, optlen)
5582 {
5583 	return _bpf_setsockopt(ctx->sk, level, optname, optval, optlen);
5584 }
5585 
5586 static const struct bpf_func_proto bpf_sock_addr_setsockopt_proto = {
5587 	.func		= bpf_sock_addr_setsockopt,
5588 	.gpl_only	= false,
5589 	.ret_type	= RET_INTEGER,
5590 	.arg1_type	= ARG_PTR_TO_CTX,
5591 	.arg2_type	= ARG_ANYTHING,
5592 	.arg3_type	= ARG_ANYTHING,
5593 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5594 	.arg5_type	= ARG_CONST_SIZE,
5595 };
5596 
BPF_CALL_5(bpf_sock_addr_getsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5597 BPF_CALL_5(bpf_sock_addr_getsockopt, struct bpf_sock_addr_kern *, ctx,
5598 	   int, level, int, optname, char *, optval, int, optlen)
5599 {
5600 	return _bpf_getsockopt(ctx->sk, level, optname, optval, optlen);
5601 }
5602 
5603 static const struct bpf_func_proto bpf_sock_addr_getsockopt_proto = {
5604 	.func		= bpf_sock_addr_getsockopt,
5605 	.gpl_only	= false,
5606 	.ret_type	= RET_INTEGER,
5607 	.arg1_type	= ARG_PTR_TO_CTX,
5608 	.arg2_type	= ARG_ANYTHING,
5609 	.arg3_type	= ARG_ANYTHING,
5610 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5611 	.arg5_type	= ARG_CONST_SIZE,
5612 };
5613 
BPF_CALL_5(bpf_sock_ops_setsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5614 BPF_CALL_5(bpf_sock_ops_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5615 	   int, level, int, optname, char *, optval, int, optlen)
5616 {
5617 	return _bpf_setsockopt(bpf_sock->sk, level, optname, optval, optlen);
5618 }
5619 
5620 static const struct bpf_func_proto bpf_sock_ops_setsockopt_proto = {
5621 	.func		= bpf_sock_ops_setsockopt,
5622 	.gpl_only	= false,
5623 	.ret_type	= RET_INTEGER,
5624 	.arg1_type	= ARG_PTR_TO_CTX,
5625 	.arg2_type	= ARG_ANYTHING,
5626 	.arg3_type	= ARG_ANYTHING,
5627 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5628 	.arg5_type	= ARG_CONST_SIZE,
5629 };
5630 
bpf_sock_ops_get_syn(struct bpf_sock_ops_kern * bpf_sock,int optname,const u8 ** start)5631 static int bpf_sock_ops_get_syn(struct bpf_sock_ops_kern *bpf_sock,
5632 				int optname, const u8 **start)
5633 {
5634 	struct sk_buff *syn_skb = bpf_sock->syn_skb;
5635 	const u8 *hdr_start;
5636 	int ret;
5637 
5638 	if (syn_skb) {
5639 		/* sk is a request_sock here */
5640 
5641 		if (optname == TCP_BPF_SYN) {
5642 			hdr_start = syn_skb->data;
5643 			ret = tcp_hdrlen(syn_skb);
5644 		} else if (optname == TCP_BPF_SYN_IP) {
5645 			hdr_start = skb_network_header(syn_skb);
5646 			ret = skb_network_header_len(syn_skb) +
5647 				tcp_hdrlen(syn_skb);
5648 		} else {
5649 			/* optname == TCP_BPF_SYN_MAC */
5650 			hdr_start = skb_mac_header(syn_skb);
5651 			ret = skb_mac_header_len(syn_skb) +
5652 				skb_network_header_len(syn_skb) +
5653 				tcp_hdrlen(syn_skb);
5654 		}
5655 	} else {
5656 		struct sock *sk = bpf_sock->sk;
5657 		struct saved_syn *saved_syn;
5658 
5659 		if (sk->sk_state == TCP_NEW_SYN_RECV)
5660 			/* synack retransmit. bpf_sock->syn_skb will
5661 			 * not be available.  It has to resort to
5662 			 * saved_syn (if it is saved).
5663 			 */
5664 			saved_syn = inet_reqsk(sk)->saved_syn;
5665 		else
5666 			saved_syn = tcp_sk(sk)->saved_syn;
5667 
5668 		if (!saved_syn)
5669 			return -ENOENT;
5670 
5671 		if (optname == TCP_BPF_SYN) {
5672 			hdr_start = saved_syn->data +
5673 				saved_syn->mac_hdrlen +
5674 				saved_syn->network_hdrlen;
5675 			ret = saved_syn->tcp_hdrlen;
5676 		} else if (optname == TCP_BPF_SYN_IP) {
5677 			hdr_start = saved_syn->data +
5678 				saved_syn->mac_hdrlen;
5679 			ret = saved_syn->network_hdrlen +
5680 				saved_syn->tcp_hdrlen;
5681 		} else {
5682 			/* optname == TCP_BPF_SYN_MAC */
5683 
5684 			/* TCP_SAVE_SYN may not have saved the mac hdr */
5685 			if (!saved_syn->mac_hdrlen)
5686 				return -ENOENT;
5687 
5688 			hdr_start = saved_syn->data;
5689 			ret = saved_syn->mac_hdrlen +
5690 				saved_syn->network_hdrlen +
5691 				saved_syn->tcp_hdrlen;
5692 		}
5693 	}
5694 
5695 	*start = hdr_start;
5696 	return ret;
5697 }
5698 
BPF_CALL_5(bpf_sock_ops_getsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5699 BPF_CALL_5(bpf_sock_ops_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5700 	   int, level, int, optname, char *, optval, int, optlen)
5701 {
5702 	if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP &&
5703 	    optname >= TCP_BPF_SYN && optname <= TCP_BPF_SYN_MAC) {
5704 		int ret, copy_len = 0;
5705 		const u8 *start;
5706 
5707 		ret = bpf_sock_ops_get_syn(bpf_sock, optname, &start);
5708 		if (ret > 0) {
5709 			copy_len = ret;
5710 			if (optlen < copy_len) {
5711 				copy_len = optlen;
5712 				ret = -ENOSPC;
5713 			}
5714 
5715 			memcpy(optval, start, copy_len);
5716 		}
5717 
5718 		/* Zero out unused buffer at the end */
5719 		memset(optval + copy_len, 0, optlen - copy_len);
5720 
5721 		return ret;
5722 	}
5723 
5724 	return _bpf_getsockopt(bpf_sock->sk, level, optname, optval, optlen);
5725 }
5726 
5727 static const struct bpf_func_proto bpf_sock_ops_getsockopt_proto = {
5728 	.func		= bpf_sock_ops_getsockopt,
5729 	.gpl_only	= false,
5730 	.ret_type	= RET_INTEGER,
5731 	.arg1_type	= ARG_PTR_TO_CTX,
5732 	.arg2_type	= ARG_ANYTHING,
5733 	.arg3_type	= ARG_ANYTHING,
5734 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5735 	.arg5_type	= ARG_CONST_SIZE,
5736 };
5737 
BPF_CALL_2(bpf_sock_ops_cb_flags_set,struct bpf_sock_ops_kern *,bpf_sock,int,argval)5738 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
5739 	   int, argval)
5740 {
5741 	struct sock *sk = bpf_sock->sk;
5742 	int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
5743 
5744 	if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
5745 		return -EINVAL;
5746 
5747 	tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
5748 
5749 	return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
5750 }
5751 
5752 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
5753 	.func		= bpf_sock_ops_cb_flags_set,
5754 	.gpl_only	= false,
5755 	.ret_type	= RET_INTEGER,
5756 	.arg1_type	= ARG_PTR_TO_CTX,
5757 	.arg2_type	= ARG_ANYTHING,
5758 };
5759 
5760 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
5761 EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
5762 
BPF_CALL_3(bpf_bind,struct bpf_sock_addr_kern *,ctx,struct sockaddr *,addr,int,addr_len)5763 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
5764 	   int, addr_len)
5765 {
5766 #ifdef CONFIG_INET
5767 	struct sock *sk = ctx->sk;
5768 	u32 flags = BIND_FROM_BPF;
5769 	int err;
5770 
5771 	err = -EINVAL;
5772 	if (addr_len < offsetofend(struct sockaddr, sa_family))
5773 		return err;
5774 	if (addr->sa_family == AF_INET) {
5775 		if (addr_len < sizeof(struct sockaddr_in))
5776 			return err;
5777 		if (((struct sockaddr_in *)addr)->sin_port == htons(0))
5778 			flags |= BIND_FORCE_ADDRESS_NO_PORT;
5779 		return __inet_bind(sk, addr, addr_len, flags);
5780 #if IS_ENABLED(CONFIG_IPV6)
5781 	} else if (addr->sa_family == AF_INET6) {
5782 		if (addr_len < SIN6_LEN_RFC2133)
5783 			return err;
5784 		if (((struct sockaddr_in6 *)addr)->sin6_port == htons(0))
5785 			flags |= BIND_FORCE_ADDRESS_NO_PORT;
5786 		/* ipv6_bpf_stub cannot be NULL, since it's called from
5787 		 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded
5788 		 */
5789 		return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, flags);
5790 #endif /* CONFIG_IPV6 */
5791 	}
5792 #endif /* CONFIG_INET */
5793 
5794 	return -EAFNOSUPPORT;
5795 }
5796 
5797 static const struct bpf_func_proto bpf_bind_proto = {
5798 	.func		= bpf_bind,
5799 	.gpl_only	= false,
5800 	.ret_type	= RET_INTEGER,
5801 	.arg1_type	= ARG_PTR_TO_CTX,
5802 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5803 	.arg3_type	= ARG_CONST_SIZE,
5804 };
5805 
5806 #ifdef CONFIG_XFRM
5807 
5808 #if (IS_BUILTIN(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \
5809     (IS_MODULE(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))
5810 
5811 struct metadata_dst __percpu *xfrm_bpf_md_dst;
5812 EXPORT_SYMBOL_GPL(xfrm_bpf_md_dst);
5813 
5814 #endif
5815 
BPF_CALL_5(bpf_skb_get_xfrm_state,struct sk_buff *,skb,u32,index,struct bpf_xfrm_state *,to,u32,size,u64,flags)5816 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
5817 	   struct bpf_xfrm_state *, to, u32, size, u64, flags)
5818 {
5819 	const struct sec_path *sp = skb_sec_path(skb);
5820 	const struct xfrm_state *x;
5821 
5822 	if (!sp || unlikely(index >= sp->len || flags))
5823 		goto err_clear;
5824 
5825 	x = sp->xvec[index];
5826 
5827 	if (unlikely(size != sizeof(struct bpf_xfrm_state)))
5828 		goto err_clear;
5829 
5830 	to->reqid = x->props.reqid;
5831 	to->spi = x->id.spi;
5832 	to->family = x->props.family;
5833 	to->ext = 0;
5834 
5835 	if (to->family == AF_INET6) {
5836 		memcpy(to->remote_ipv6, x->props.saddr.a6,
5837 		       sizeof(to->remote_ipv6));
5838 	} else {
5839 		to->remote_ipv4 = x->props.saddr.a4;
5840 		memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
5841 	}
5842 
5843 	return 0;
5844 err_clear:
5845 	memset(to, 0, size);
5846 	return -EINVAL;
5847 }
5848 
5849 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
5850 	.func		= bpf_skb_get_xfrm_state,
5851 	.gpl_only	= false,
5852 	.ret_type	= RET_INTEGER,
5853 	.arg1_type	= ARG_PTR_TO_CTX,
5854 	.arg2_type	= ARG_ANYTHING,
5855 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
5856 	.arg4_type	= ARG_CONST_SIZE,
5857 	.arg5_type	= ARG_ANYTHING,
5858 };
5859 #endif
5860 
5861 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6)
bpf_fib_set_fwd_params(struct bpf_fib_lookup * params,u32 mtu)5862 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, u32 mtu)
5863 {
5864 	params->h_vlan_TCI = 0;
5865 	params->h_vlan_proto = 0;
5866 	if (mtu)
5867 		params->mtu_result = mtu; /* union with tot_len */
5868 
5869 	return 0;
5870 }
5871 #endif
5872 
5873 #if IS_ENABLED(CONFIG_INET)
bpf_ipv4_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5874 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5875 			       u32 flags, bool check_mtu)
5876 {
5877 	struct fib_nh_common *nhc;
5878 	struct in_device *in_dev;
5879 	struct neighbour *neigh;
5880 	struct net_device *dev;
5881 	struct fib_result res;
5882 	struct flowi4 fl4;
5883 	u32 mtu = 0;
5884 	int err;
5885 
5886 	dev = dev_get_by_index_rcu(net, params->ifindex);
5887 	if (unlikely(!dev))
5888 		return -ENODEV;
5889 
5890 	/* verify forwarding is enabled on this interface */
5891 	in_dev = __in_dev_get_rcu(dev);
5892 	if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
5893 		return BPF_FIB_LKUP_RET_FWD_DISABLED;
5894 
5895 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5896 		fl4.flowi4_iif = 1;
5897 		fl4.flowi4_oif = params->ifindex;
5898 	} else {
5899 		fl4.flowi4_iif = params->ifindex;
5900 		fl4.flowi4_oif = 0;
5901 	}
5902 	fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
5903 	fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
5904 	fl4.flowi4_flags = 0;
5905 
5906 	fl4.flowi4_proto = params->l4_protocol;
5907 	fl4.daddr = params->ipv4_dst;
5908 	fl4.saddr = params->ipv4_src;
5909 	fl4.fl4_sport = params->sport;
5910 	fl4.fl4_dport = params->dport;
5911 	fl4.flowi4_multipath_hash = 0;
5912 
5913 	if (flags & BPF_FIB_LOOKUP_DIRECT) {
5914 		u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5915 		struct fib_table *tb;
5916 
5917 		if (flags & BPF_FIB_LOOKUP_TBID) {
5918 			tbid = params->tbid;
5919 			/* zero out for vlan output */
5920 			params->tbid = 0;
5921 		}
5922 
5923 		tb = fib_get_table(net, tbid);
5924 		if (unlikely(!tb))
5925 			return BPF_FIB_LKUP_RET_NOT_FWDED;
5926 
5927 		err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
5928 	} else {
5929 		fl4.flowi4_mark = 0;
5930 		fl4.flowi4_secid = 0;
5931 		fl4.flowi4_tun_key.tun_id = 0;
5932 		fl4.flowi4_uid = sock_net_uid(net, NULL);
5933 
5934 		err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
5935 	}
5936 
5937 	if (err) {
5938 		/* map fib lookup errors to RTN_ type */
5939 		if (err == -EINVAL)
5940 			return BPF_FIB_LKUP_RET_BLACKHOLE;
5941 		if (err == -EHOSTUNREACH)
5942 			return BPF_FIB_LKUP_RET_UNREACHABLE;
5943 		if (err == -EACCES)
5944 			return BPF_FIB_LKUP_RET_PROHIBIT;
5945 
5946 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5947 	}
5948 
5949 	if (res.type != RTN_UNICAST)
5950 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5951 
5952 	if (fib_info_num_path(res.fi) > 1)
5953 		fib_select_path(net, &res, &fl4, NULL);
5954 
5955 	if (check_mtu) {
5956 		mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
5957 		if (params->tot_len > mtu) {
5958 			params->mtu_result = mtu; /* union with tot_len */
5959 			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5960 		}
5961 	}
5962 
5963 	nhc = res.nhc;
5964 
5965 	/* do not handle lwt encaps right now */
5966 	if (nhc->nhc_lwtstate)
5967 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5968 
5969 	dev = nhc->nhc_dev;
5970 
5971 	params->rt_metric = res.fi->fib_priority;
5972 	params->ifindex = dev->ifindex;
5973 
5974 	if (flags & BPF_FIB_LOOKUP_SRC)
5975 		params->ipv4_src = fib_result_prefsrc(net, &res);
5976 
5977 	/* xdp and cls_bpf programs are run in RCU-bh so
5978 	 * rcu_read_lock_bh is not needed here
5979 	 */
5980 	if (likely(nhc->nhc_gw_family != AF_INET6)) {
5981 		if (nhc->nhc_gw_family)
5982 			params->ipv4_dst = nhc->nhc_gw.ipv4;
5983 	} else {
5984 		struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;
5985 
5986 		params->family = AF_INET6;
5987 		*dst = nhc->nhc_gw.ipv6;
5988 	}
5989 
5990 	if (flags & BPF_FIB_LOOKUP_SKIP_NEIGH)
5991 		goto set_fwd_params;
5992 
5993 	if (likely(nhc->nhc_gw_family != AF_INET6))
5994 		neigh = __ipv4_neigh_lookup_noref(dev,
5995 						  (__force u32)params->ipv4_dst);
5996 	else
5997 		neigh = __ipv6_neigh_lookup_noref_stub(dev, params->ipv6_dst);
5998 
5999 	if (!neigh || !(READ_ONCE(neigh->nud_state) & NUD_VALID))
6000 		return BPF_FIB_LKUP_RET_NO_NEIGH;
6001 	memcpy(params->dmac, neigh->ha, ETH_ALEN);
6002 	memcpy(params->smac, dev->dev_addr, ETH_ALEN);
6003 
6004 set_fwd_params:
6005 	return bpf_fib_set_fwd_params(params, mtu);
6006 }
6007 #endif
6008 
6009 #if IS_ENABLED(CONFIG_IPV6)
bpf_ipv6_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)6010 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
6011 			       u32 flags, bool check_mtu)
6012 {
6013 	struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
6014 	struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
6015 	struct fib6_result res = {};
6016 	struct neighbour *neigh;
6017 	struct net_device *dev;
6018 	struct inet6_dev *idev;
6019 	struct flowi6 fl6;
6020 	int strict = 0;
6021 	int oif, err;
6022 	u32 mtu = 0;
6023 
6024 	/* link local addresses are never forwarded */
6025 	if (rt6_need_strict(dst) || rt6_need_strict(src))
6026 		return BPF_FIB_LKUP_RET_NOT_FWDED;
6027 
6028 	dev = dev_get_by_index_rcu(net, params->ifindex);
6029 	if (unlikely(!dev))
6030 		return -ENODEV;
6031 
6032 	idev = __in6_dev_get_safely(dev);
6033 	if (unlikely(!idev || !idev->cnf.forwarding))
6034 		return BPF_FIB_LKUP_RET_FWD_DISABLED;
6035 
6036 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
6037 		fl6.flowi6_iif = 1;
6038 		oif = fl6.flowi6_oif = params->ifindex;
6039 	} else {
6040 		oif = fl6.flowi6_iif = params->ifindex;
6041 		fl6.flowi6_oif = 0;
6042 		strict = RT6_LOOKUP_F_HAS_SADDR;
6043 	}
6044 	fl6.flowlabel = params->flowinfo;
6045 	fl6.flowi6_scope = 0;
6046 	fl6.flowi6_flags = 0;
6047 	fl6.mp_hash = 0;
6048 
6049 	fl6.flowi6_proto = params->l4_protocol;
6050 	fl6.daddr = *dst;
6051 	fl6.saddr = *src;
6052 	fl6.fl6_sport = params->sport;
6053 	fl6.fl6_dport = params->dport;
6054 
6055 	if (flags & BPF_FIB_LOOKUP_DIRECT) {
6056 		u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
6057 		struct fib6_table *tb;
6058 
6059 		if (flags & BPF_FIB_LOOKUP_TBID) {
6060 			tbid = params->tbid;
6061 			/* zero out for vlan output */
6062 			params->tbid = 0;
6063 		}
6064 
6065 		tb = ipv6_stub->fib6_get_table(net, tbid);
6066 		if (unlikely(!tb))
6067 			return BPF_FIB_LKUP_RET_NOT_FWDED;
6068 
6069 		err = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, &res,
6070 						   strict);
6071 	} else {
6072 		fl6.flowi6_mark = 0;
6073 		fl6.flowi6_secid = 0;
6074 		fl6.flowi6_tun_key.tun_id = 0;
6075 		fl6.flowi6_uid = sock_net_uid(net, NULL);
6076 
6077 		err = ipv6_stub->fib6_lookup(net, oif, &fl6, &res, strict);
6078 	}
6079 
6080 	if (unlikely(err || IS_ERR_OR_NULL(res.f6i) ||
6081 		     res.f6i == net->ipv6.fib6_null_entry))
6082 		return BPF_FIB_LKUP_RET_NOT_FWDED;
6083 
6084 	switch (res.fib6_type) {
6085 	/* only unicast is forwarded */
6086 	case RTN_UNICAST:
6087 		break;
6088 	case RTN_BLACKHOLE:
6089 		return BPF_FIB_LKUP_RET_BLACKHOLE;
6090 	case RTN_UNREACHABLE:
6091 		return BPF_FIB_LKUP_RET_UNREACHABLE;
6092 	case RTN_PROHIBIT:
6093 		return BPF_FIB_LKUP_RET_PROHIBIT;
6094 	default:
6095 		return BPF_FIB_LKUP_RET_NOT_FWDED;
6096 	}
6097 
6098 	ipv6_stub->fib6_select_path(net, &res, &fl6, fl6.flowi6_oif,
6099 				    fl6.flowi6_oif != 0, NULL, strict);
6100 
6101 	if (check_mtu) {
6102 		mtu = ipv6_stub->ip6_mtu_from_fib6(&res, dst, src);
6103 		if (params->tot_len > mtu) {
6104 			params->mtu_result = mtu; /* union with tot_len */
6105 			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
6106 		}
6107 	}
6108 
6109 	if (res.nh->fib_nh_lws)
6110 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
6111 
6112 	if (res.nh->fib_nh_gw_family)
6113 		*dst = res.nh->fib_nh_gw6;
6114 
6115 	dev = res.nh->fib_nh_dev;
6116 	params->rt_metric = res.f6i->fib6_metric;
6117 	params->ifindex = dev->ifindex;
6118 
6119 	if (flags & BPF_FIB_LOOKUP_SRC) {
6120 		if (res.f6i->fib6_prefsrc.plen) {
6121 			*src = res.f6i->fib6_prefsrc.addr;
6122 		} else {
6123 			err = ipv6_bpf_stub->ipv6_dev_get_saddr(net, dev,
6124 								&fl6.daddr, 0,
6125 								src);
6126 			if (err)
6127 				return BPF_FIB_LKUP_RET_NO_SRC_ADDR;
6128 		}
6129 	}
6130 
6131 	if (flags & BPF_FIB_LOOKUP_SKIP_NEIGH)
6132 		goto set_fwd_params;
6133 
6134 	/* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
6135 	 * not needed here.
6136 	 */
6137 	neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
6138 	if (!neigh || !(READ_ONCE(neigh->nud_state) & NUD_VALID))
6139 		return BPF_FIB_LKUP_RET_NO_NEIGH;
6140 	memcpy(params->dmac, neigh->ha, ETH_ALEN);
6141 	memcpy(params->smac, dev->dev_addr, ETH_ALEN);
6142 
6143 set_fwd_params:
6144 	return bpf_fib_set_fwd_params(params, mtu);
6145 }
6146 #endif
6147 
6148 #define BPF_FIB_LOOKUP_MASK (BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT | \
6149 			     BPF_FIB_LOOKUP_SKIP_NEIGH | BPF_FIB_LOOKUP_TBID | \
6150 			     BPF_FIB_LOOKUP_SRC)
6151 
BPF_CALL_4(bpf_xdp_fib_lookup,struct xdp_buff *,ctx,struct bpf_fib_lookup *,params,int,plen,u32,flags)6152 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
6153 	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
6154 {
6155 	if (plen < sizeof(*params))
6156 		return -EINVAL;
6157 
6158 	if (flags & ~BPF_FIB_LOOKUP_MASK)
6159 		return -EINVAL;
6160 
6161 	switch (params->family) {
6162 #if IS_ENABLED(CONFIG_INET)
6163 	case AF_INET:
6164 		return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
6165 					   flags, true);
6166 #endif
6167 #if IS_ENABLED(CONFIG_IPV6)
6168 	case AF_INET6:
6169 		return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
6170 					   flags, true);
6171 #endif
6172 	}
6173 	return -EAFNOSUPPORT;
6174 }
6175 
6176 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
6177 	.func		= bpf_xdp_fib_lookup,
6178 	.gpl_only	= true,
6179 	.ret_type	= RET_INTEGER,
6180 	.arg1_type      = ARG_PTR_TO_CTX,
6181 	.arg2_type      = ARG_PTR_TO_MEM,
6182 	.arg3_type      = ARG_CONST_SIZE,
6183 	.arg4_type	= ARG_ANYTHING,
6184 };
6185 
BPF_CALL_4(bpf_skb_fib_lookup,struct sk_buff *,skb,struct bpf_fib_lookup *,params,int,plen,u32,flags)6186 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
6187 	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
6188 {
6189 	struct net *net = dev_net(skb->dev);
6190 	int rc = -EAFNOSUPPORT;
6191 	bool check_mtu = false;
6192 
6193 	if (plen < sizeof(*params))
6194 		return -EINVAL;
6195 
6196 	if (flags & ~BPF_FIB_LOOKUP_MASK)
6197 		return -EINVAL;
6198 
6199 	if (params->tot_len)
6200 		check_mtu = true;
6201 
6202 	switch (params->family) {
6203 #if IS_ENABLED(CONFIG_INET)
6204 	case AF_INET:
6205 		rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu);
6206 		break;
6207 #endif
6208 #if IS_ENABLED(CONFIG_IPV6)
6209 	case AF_INET6:
6210 		rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu);
6211 		break;
6212 #endif
6213 	}
6214 
6215 	if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) {
6216 		struct net_device *dev;
6217 
6218 		/* When tot_len isn't provided by user, check skb
6219 		 * against MTU of FIB lookup resulting net_device
6220 		 */
6221 		dev = dev_get_by_index_rcu(net, params->ifindex);
6222 		if (!is_skb_forwardable(dev, skb))
6223 			rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
6224 
6225 		params->mtu_result = dev->mtu; /* union with tot_len */
6226 	}
6227 
6228 	return rc;
6229 }
6230 
6231 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
6232 	.func		= bpf_skb_fib_lookup,
6233 	.gpl_only	= true,
6234 	.ret_type	= RET_INTEGER,
6235 	.arg1_type      = ARG_PTR_TO_CTX,
6236 	.arg2_type      = ARG_PTR_TO_MEM,
6237 	.arg3_type      = ARG_CONST_SIZE,
6238 	.arg4_type	= ARG_ANYTHING,
6239 };
6240 
__dev_via_ifindex(struct net_device * dev_curr,u32 ifindex)6241 static struct net_device *__dev_via_ifindex(struct net_device *dev_curr,
6242 					    u32 ifindex)
6243 {
6244 	struct net *netns = dev_net(dev_curr);
6245 
6246 	/* Non-redirect use-cases can use ifindex=0 and save ifindex lookup */
6247 	if (ifindex == 0)
6248 		return dev_curr;
6249 
6250 	return dev_get_by_index_rcu(netns, ifindex);
6251 }
6252 
BPF_CALL_5(bpf_skb_check_mtu,struct sk_buff *,skb,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6253 BPF_CALL_5(bpf_skb_check_mtu, struct sk_buff *, skb,
6254 	   u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6255 {
6256 	int ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6257 	struct net_device *dev = skb->dev;
6258 	int mtu, dev_len, skb_len;
6259 
6260 	if (unlikely(flags & ~(BPF_MTU_CHK_SEGS)))
6261 		return -EINVAL;
6262 	if (unlikely(flags & BPF_MTU_CHK_SEGS && (len_diff || *mtu_len)))
6263 		return -EINVAL;
6264 
6265 	dev = __dev_via_ifindex(dev, ifindex);
6266 	if (unlikely(!dev))
6267 		return -ENODEV;
6268 
6269 	mtu = READ_ONCE(dev->mtu);
6270 	dev_len = mtu + dev->hard_header_len;
6271 
6272 	/* If set use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6273 	skb_len = *mtu_len ? *mtu_len + dev->hard_header_len : skb->len;
6274 
6275 	skb_len += len_diff; /* minus result pass check */
6276 	if (skb_len <= dev_len) {
6277 		ret = BPF_MTU_CHK_RET_SUCCESS;
6278 		goto out;
6279 	}
6280 	/* At this point, skb->len exceed MTU, but as it include length of all
6281 	 * segments, it can still be below MTU.  The SKB can possibly get
6282 	 * re-segmented in transmit path (see validate_xmit_skb).  Thus, user
6283 	 * must choose if segs are to be MTU checked.
6284 	 */
6285 	if (skb_is_gso(skb)) {
6286 		ret = BPF_MTU_CHK_RET_SUCCESS;
6287 		if (flags & BPF_MTU_CHK_SEGS &&
6288 		    !skb_gso_validate_network_len(skb, mtu))
6289 			ret = BPF_MTU_CHK_RET_SEGS_TOOBIG;
6290 	}
6291 out:
6292 	*mtu_len = mtu;
6293 	return ret;
6294 }
6295 
BPF_CALL_5(bpf_xdp_check_mtu,struct xdp_buff *,xdp,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6296 BPF_CALL_5(bpf_xdp_check_mtu, struct xdp_buff *, xdp,
6297 	   u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6298 {
6299 	struct net_device *dev = xdp->rxq->dev;
6300 	int xdp_len = xdp->data_end - xdp->data;
6301 	int ret = BPF_MTU_CHK_RET_SUCCESS;
6302 	int mtu, dev_len;
6303 
6304 	/* XDP variant doesn't support multi-buffer segment check (yet) */
6305 	if (unlikely(flags))
6306 		return -EINVAL;
6307 
6308 	dev = __dev_via_ifindex(dev, ifindex);
6309 	if (unlikely(!dev))
6310 		return -ENODEV;
6311 
6312 	mtu = READ_ONCE(dev->mtu);
6313 	dev_len = mtu + dev->hard_header_len;
6314 
6315 	/* Use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6316 	if (*mtu_len)
6317 		xdp_len = *mtu_len + dev->hard_header_len;
6318 
6319 	xdp_len += len_diff; /* minus result pass check */
6320 	if (xdp_len > dev_len)
6321 		ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6322 
6323 	*mtu_len = mtu;
6324 	return ret;
6325 }
6326 
6327 static const struct bpf_func_proto bpf_skb_check_mtu_proto = {
6328 	.func		= bpf_skb_check_mtu,
6329 	.gpl_only	= true,
6330 	.ret_type	= RET_INTEGER,
6331 	.arg1_type      = ARG_PTR_TO_CTX,
6332 	.arg2_type      = ARG_ANYTHING,
6333 	.arg3_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_WRITE | MEM_ALIGNED,
6334 	.arg3_size	= sizeof(u32),
6335 	.arg4_type      = ARG_ANYTHING,
6336 	.arg5_type      = ARG_ANYTHING,
6337 };
6338 
6339 static const struct bpf_func_proto bpf_xdp_check_mtu_proto = {
6340 	.func		= bpf_xdp_check_mtu,
6341 	.gpl_only	= true,
6342 	.ret_type	= RET_INTEGER,
6343 	.arg1_type      = ARG_PTR_TO_CTX,
6344 	.arg2_type      = ARG_ANYTHING,
6345 	.arg3_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_WRITE | MEM_ALIGNED,
6346 	.arg3_size	= sizeof(u32),
6347 	.arg4_type      = ARG_ANYTHING,
6348 	.arg5_type      = ARG_ANYTHING,
6349 };
6350 
6351 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
bpf_push_seg6_encap(struct sk_buff * skb,u32 type,void * hdr,u32 len)6352 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
6353 {
6354 	int err;
6355 	struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
6356 
6357 	if (!seg6_validate_srh(srh, len, false))
6358 		return -EINVAL;
6359 
6360 	switch (type) {
6361 	case BPF_LWT_ENCAP_SEG6_INLINE:
6362 		if (skb->protocol != htons(ETH_P_IPV6))
6363 			return -EBADMSG;
6364 
6365 		err = seg6_do_srh_inline(skb, srh);
6366 		break;
6367 	case BPF_LWT_ENCAP_SEG6:
6368 		skb_reset_inner_headers(skb);
6369 		skb->encapsulation = 1;
6370 		err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
6371 		break;
6372 	default:
6373 		return -EINVAL;
6374 	}
6375 
6376 	bpf_compute_data_pointers(skb);
6377 	if (err)
6378 		return err;
6379 
6380 	skb_set_transport_header(skb, sizeof(struct ipv6hdr));
6381 
6382 	return seg6_lookup_nexthop(skb, NULL, 0);
6383 }
6384 #endif /* CONFIG_IPV6_SEG6_BPF */
6385 
6386 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
bpf_push_ip_encap(struct sk_buff * skb,void * hdr,u32 len,bool ingress)6387 static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
6388 			     bool ingress)
6389 {
6390 	return bpf_lwt_push_ip_encap(skb, hdr, len, ingress);
6391 }
6392 #endif
6393 
BPF_CALL_4(bpf_lwt_in_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6394 BPF_CALL_4(bpf_lwt_in_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
6395 	   u32, len)
6396 {
6397 	switch (type) {
6398 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
6399 	case BPF_LWT_ENCAP_SEG6:
6400 	case BPF_LWT_ENCAP_SEG6_INLINE:
6401 		return bpf_push_seg6_encap(skb, type, hdr, len);
6402 #endif
6403 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6404 	case BPF_LWT_ENCAP_IP:
6405 		return bpf_push_ip_encap(skb, hdr, len, true /* ingress */);
6406 #endif
6407 	default:
6408 		return -EINVAL;
6409 	}
6410 }
6411 
BPF_CALL_4(bpf_lwt_xmit_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6412 BPF_CALL_4(bpf_lwt_xmit_push_encap, struct sk_buff *, skb, u32, type,
6413 	   void *, hdr, u32, len)
6414 {
6415 	switch (type) {
6416 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6417 	case BPF_LWT_ENCAP_IP:
6418 		return bpf_push_ip_encap(skb, hdr, len, false /* egress */);
6419 #endif
6420 	default:
6421 		return -EINVAL;
6422 	}
6423 }
6424 
6425 static const struct bpf_func_proto bpf_lwt_in_push_encap_proto = {
6426 	.func		= bpf_lwt_in_push_encap,
6427 	.gpl_only	= false,
6428 	.ret_type	= RET_INTEGER,
6429 	.arg1_type	= ARG_PTR_TO_CTX,
6430 	.arg2_type	= ARG_ANYTHING,
6431 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6432 	.arg4_type	= ARG_CONST_SIZE
6433 };
6434 
6435 static const struct bpf_func_proto bpf_lwt_xmit_push_encap_proto = {
6436 	.func		= bpf_lwt_xmit_push_encap,
6437 	.gpl_only	= false,
6438 	.ret_type	= RET_INTEGER,
6439 	.arg1_type	= ARG_PTR_TO_CTX,
6440 	.arg2_type	= ARG_ANYTHING,
6441 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6442 	.arg4_type	= ARG_CONST_SIZE
6443 };
6444 
6445 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
BPF_CALL_4(bpf_lwt_seg6_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len)6446 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
6447 	   const void *, from, u32, len)
6448 {
6449 	struct seg6_bpf_srh_state *srh_state =
6450 		this_cpu_ptr(&seg6_bpf_srh_states);
6451 	struct ipv6_sr_hdr *srh = srh_state->srh;
6452 	void *srh_tlvs, *srh_end, *ptr;
6453 	int srhoff = 0;
6454 
6455 	if (srh == NULL)
6456 		return -EINVAL;
6457 
6458 	srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
6459 	srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
6460 
6461 	ptr = skb->data + offset;
6462 	if (ptr >= srh_tlvs && ptr + len <= srh_end)
6463 		srh_state->valid = false;
6464 	else if (ptr < (void *)&srh->flags ||
6465 		 ptr + len > (void *)&srh->segments)
6466 		return -EFAULT;
6467 
6468 	if (unlikely(bpf_try_make_writable(skb, offset + len)))
6469 		return -EFAULT;
6470 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6471 		return -EINVAL;
6472 	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6473 
6474 	memcpy(skb->data + offset, from, len);
6475 	return 0;
6476 }
6477 
6478 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
6479 	.func		= bpf_lwt_seg6_store_bytes,
6480 	.gpl_only	= false,
6481 	.ret_type	= RET_INTEGER,
6482 	.arg1_type	= ARG_PTR_TO_CTX,
6483 	.arg2_type	= ARG_ANYTHING,
6484 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6485 	.arg4_type	= ARG_CONST_SIZE
6486 };
6487 
bpf_update_srh_state(struct sk_buff * skb)6488 static void bpf_update_srh_state(struct sk_buff *skb)
6489 {
6490 	struct seg6_bpf_srh_state *srh_state =
6491 		this_cpu_ptr(&seg6_bpf_srh_states);
6492 	int srhoff = 0;
6493 
6494 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
6495 		srh_state->srh = NULL;
6496 	} else {
6497 		srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6498 		srh_state->hdrlen = srh_state->srh->hdrlen << 3;
6499 		srh_state->valid = true;
6500 	}
6501 }
6502 
BPF_CALL_4(bpf_lwt_seg6_action,struct sk_buff *,skb,u32,action,void *,param,u32,param_len)6503 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
6504 	   u32, action, void *, param, u32, param_len)
6505 {
6506 	struct seg6_bpf_srh_state *srh_state =
6507 		this_cpu_ptr(&seg6_bpf_srh_states);
6508 	int hdroff = 0;
6509 	int err;
6510 
6511 	switch (action) {
6512 	case SEG6_LOCAL_ACTION_END_X:
6513 		if (!seg6_bpf_has_valid_srh(skb))
6514 			return -EBADMSG;
6515 		if (param_len != sizeof(struct in6_addr))
6516 			return -EINVAL;
6517 		return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
6518 	case SEG6_LOCAL_ACTION_END_T:
6519 		if (!seg6_bpf_has_valid_srh(skb))
6520 			return -EBADMSG;
6521 		if (param_len != sizeof(int))
6522 			return -EINVAL;
6523 		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6524 	case SEG6_LOCAL_ACTION_END_DT6:
6525 		if (!seg6_bpf_has_valid_srh(skb))
6526 			return -EBADMSG;
6527 		if (param_len != sizeof(int))
6528 			return -EINVAL;
6529 
6530 		if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
6531 			return -EBADMSG;
6532 		if (!pskb_pull(skb, hdroff))
6533 			return -EBADMSG;
6534 
6535 		skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
6536 		skb_reset_network_header(skb);
6537 		skb_reset_transport_header(skb);
6538 		skb->encapsulation = 0;
6539 
6540 		bpf_compute_data_pointers(skb);
6541 		bpf_update_srh_state(skb);
6542 		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6543 	case SEG6_LOCAL_ACTION_END_B6:
6544 		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6545 			return -EBADMSG;
6546 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
6547 					  param, param_len);
6548 		if (!err)
6549 			bpf_update_srh_state(skb);
6550 
6551 		return err;
6552 	case SEG6_LOCAL_ACTION_END_B6_ENCAP:
6553 		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6554 			return -EBADMSG;
6555 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
6556 					  param, param_len);
6557 		if (!err)
6558 			bpf_update_srh_state(skb);
6559 
6560 		return err;
6561 	default:
6562 		return -EINVAL;
6563 	}
6564 }
6565 
6566 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
6567 	.func		= bpf_lwt_seg6_action,
6568 	.gpl_only	= false,
6569 	.ret_type	= RET_INTEGER,
6570 	.arg1_type	= ARG_PTR_TO_CTX,
6571 	.arg2_type	= ARG_ANYTHING,
6572 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6573 	.arg4_type	= ARG_CONST_SIZE
6574 };
6575 
BPF_CALL_3(bpf_lwt_seg6_adjust_srh,struct sk_buff *,skb,u32,offset,s32,len)6576 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
6577 	   s32, len)
6578 {
6579 	struct seg6_bpf_srh_state *srh_state =
6580 		this_cpu_ptr(&seg6_bpf_srh_states);
6581 	struct ipv6_sr_hdr *srh = srh_state->srh;
6582 	void *srh_end, *srh_tlvs, *ptr;
6583 	struct ipv6hdr *hdr;
6584 	int srhoff = 0;
6585 	int ret;
6586 
6587 	if (unlikely(srh == NULL))
6588 		return -EINVAL;
6589 
6590 	srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
6591 			((srh->first_segment + 1) << 4));
6592 	srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
6593 			srh_state->hdrlen);
6594 	ptr = skb->data + offset;
6595 
6596 	if (unlikely(ptr < srh_tlvs || ptr > srh_end))
6597 		return -EFAULT;
6598 	if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
6599 		return -EFAULT;
6600 
6601 	if (len > 0) {
6602 		ret = skb_cow_head(skb, len);
6603 		if (unlikely(ret < 0))
6604 			return ret;
6605 
6606 		ret = bpf_skb_net_hdr_push(skb, offset, len);
6607 	} else {
6608 		ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
6609 	}
6610 
6611 	bpf_compute_data_pointers(skb);
6612 	if (unlikely(ret < 0))
6613 		return ret;
6614 
6615 	hdr = (struct ipv6hdr *)skb->data;
6616 	hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
6617 
6618 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6619 		return -EINVAL;
6620 	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6621 	srh_state->hdrlen += len;
6622 	srh_state->valid = false;
6623 	return 0;
6624 }
6625 
6626 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
6627 	.func		= bpf_lwt_seg6_adjust_srh,
6628 	.gpl_only	= false,
6629 	.ret_type	= RET_INTEGER,
6630 	.arg1_type	= ARG_PTR_TO_CTX,
6631 	.arg2_type	= ARG_ANYTHING,
6632 	.arg3_type	= ARG_ANYTHING,
6633 };
6634 #endif /* CONFIG_IPV6_SEG6_BPF */
6635 
6636 #ifdef CONFIG_INET
sk_lookup(struct net * net,struct bpf_sock_tuple * tuple,int dif,int sdif,u8 family,u8 proto)6637 static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
6638 			      int dif, int sdif, u8 family, u8 proto)
6639 {
6640 	struct inet_hashinfo *hinfo = net->ipv4.tcp_death_row.hashinfo;
6641 	bool refcounted = false;
6642 	struct sock *sk = NULL;
6643 
6644 	if (family == AF_INET) {
6645 		__be32 src4 = tuple->ipv4.saddr;
6646 		__be32 dst4 = tuple->ipv4.daddr;
6647 
6648 		if (proto == IPPROTO_TCP)
6649 			sk = __inet_lookup(net, hinfo, NULL, 0,
6650 					   src4, tuple->ipv4.sport,
6651 					   dst4, tuple->ipv4.dport,
6652 					   dif, sdif, &refcounted);
6653 		else
6654 			sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
6655 					       dst4, tuple->ipv4.dport,
6656 					       dif, sdif, net->ipv4.udp_table, NULL);
6657 #if IS_ENABLED(CONFIG_IPV6)
6658 	} else {
6659 		struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
6660 		struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;
6661 
6662 		if (proto == IPPROTO_TCP)
6663 			sk = __inet6_lookup(net, hinfo, NULL, 0,
6664 					    src6, tuple->ipv6.sport,
6665 					    dst6, ntohs(tuple->ipv6.dport),
6666 					    dif, sdif, &refcounted);
6667 		else if (likely(ipv6_bpf_stub))
6668 			sk = ipv6_bpf_stub->udp6_lib_lookup(net,
6669 							    src6, tuple->ipv6.sport,
6670 							    dst6, tuple->ipv6.dport,
6671 							    dif, sdif,
6672 							    net->ipv4.udp_table, NULL);
6673 #endif
6674 	}
6675 
6676 	if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
6677 		WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6678 		sk = NULL;
6679 	}
6680 	return sk;
6681 }
6682 
6683 /* bpf_skc_lookup performs the core lookup for different types of sockets,
6684  * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
6685  */
6686 static struct sock *
__bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags,int sdif)6687 __bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6688 		 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6689 		 u64 flags, int sdif)
6690 {
6691 	struct sock *sk = NULL;
6692 	struct net *net;
6693 	u8 family;
6694 
6695 	if (len == sizeof(tuple->ipv4))
6696 		family = AF_INET;
6697 	else if (len == sizeof(tuple->ipv6))
6698 		family = AF_INET6;
6699 	else
6700 		return NULL;
6701 
6702 	if (unlikely(flags || !((s32)netns_id < 0 || netns_id <= S32_MAX)))
6703 		goto out;
6704 
6705 	if (sdif < 0) {
6706 		if (family == AF_INET)
6707 			sdif = inet_sdif(skb);
6708 		else
6709 			sdif = inet6_sdif(skb);
6710 	}
6711 
6712 	if ((s32)netns_id < 0) {
6713 		net = caller_net;
6714 		sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6715 	} else {
6716 		net = get_net_ns_by_id(caller_net, netns_id);
6717 		if (unlikely(!net))
6718 			goto out;
6719 		sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6720 		put_net(net);
6721 	}
6722 
6723 out:
6724 	return sk;
6725 }
6726 
6727 static struct sock *
__bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags,int sdif)6728 __bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6729 		struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6730 		u64 flags, int sdif)
6731 {
6732 	struct sock *sk = __bpf_skc_lookup(skb, tuple, len, caller_net,
6733 					   ifindex, proto, netns_id, flags,
6734 					   sdif);
6735 
6736 	if (sk) {
6737 		struct sock *sk2 = sk_to_full_sk(sk);
6738 
6739 		/* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6740 		 * sock refcnt is decremented to prevent a request_sock leak.
6741 		 */
6742 		if (!sk_fullsock(sk2))
6743 			sk2 = NULL;
6744 		if (sk2 != sk) {
6745 			sock_gen_put(sk);
6746 			/* Ensure there is no need to bump sk2 refcnt */
6747 			if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6748 				WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6749 				return NULL;
6750 			}
6751 			sk = sk2;
6752 		}
6753 	}
6754 
6755 	return sk;
6756 }
6757 
6758 static struct sock *
bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6759 bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6760 	       u8 proto, u64 netns_id, u64 flags)
6761 {
6762 	struct net *caller_net;
6763 	int ifindex;
6764 
6765 	if (skb->dev) {
6766 		caller_net = dev_net(skb->dev);
6767 		ifindex = skb->dev->ifindex;
6768 	} else {
6769 		caller_net = sock_net(skb->sk);
6770 		ifindex = 0;
6771 	}
6772 
6773 	return __bpf_skc_lookup(skb, tuple, len, caller_net, ifindex, proto,
6774 				netns_id, flags, -1);
6775 }
6776 
6777 static struct sock *
bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6778 bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6779 	      u8 proto, u64 netns_id, u64 flags)
6780 {
6781 	struct sock *sk = bpf_skc_lookup(skb, tuple, len, proto, netns_id,
6782 					 flags);
6783 
6784 	if (sk) {
6785 		struct sock *sk2 = sk_to_full_sk(sk);
6786 
6787 		/* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6788 		 * sock refcnt is decremented to prevent a request_sock leak.
6789 		 */
6790 		if (!sk_fullsock(sk2))
6791 			sk2 = NULL;
6792 		if (sk2 != sk) {
6793 			sock_gen_put(sk);
6794 			/* Ensure there is no need to bump sk2 refcnt */
6795 			if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6796 				WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6797 				return NULL;
6798 			}
6799 			sk = sk2;
6800 		}
6801 	}
6802 
6803 	return sk;
6804 }
6805 
BPF_CALL_5(bpf_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6806 BPF_CALL_5(bpf_skc_lookup_tcp, struct sk_buff *, skb,
6807 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6808 {
6809 	return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
6810 					     netns_id, flags);
6811 }
6812 
6813 static const struct bpf_func_proto bpf_skc_lookup_tcp_proto = {
6814 	.func		= bpf_skc_lookup_tcp,
6815 	.gpl_only	= false,
6816 	.pkt_access	= true,
6817 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
6818 	.arg1_type	= ARG_PTR_TO_CTX,
6819 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6820 	.arg3_type	= ARG_CONST_SIZE,
6821 	.arg4_type	= ARG_ANYTHING,
6822 	.arg5_type	= ARG_ANYTHING,
6823 };
6824 
BPF_CALL_5(bpf_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6825 BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
6826 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6827 {
6828 	return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
6829 					    netns_id, flags);
6830 }
6831 
6832 static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
6833 	.func		= bpf_sk_lookup_tcp,
6834 	.gpl_only	= false,
6835 	.pkt_access	= true,
6836 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6837 	.arg1_type	= ARG_PTR_TO_CTX,
6838 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6839 	.arg3_type	= ARG_CONST_SIZE,
6840 	.arg4_type	= ARG_ANYTHING,
6841 	.arg5_type	= ARG_ANYTHING,
6842 };
6843 
BPF_CALL_5(bpf_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6844 BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
6845 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6846 {
6847 	return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
6848 					    netns_id, flags);
6849 }
6850 
6851 static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
6852 	.func		= bpf_sk_lookup_udp,
6853 	.gpl_only	= false,
6854 	.pkt_access	= true,
6855 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6856 	.arg1_type	= ARG_PTR_TO_CTX,
6857 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6858 	.arg3_type	= ARG_CONST_SIZE,
6859 	.arg4_type	= ARG_ANYTHING,
6860 	.arg5_type	= ARG_ANYTHING,
6861 };
6862 
BPF_CALL_5(bpf_tc_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6863 BPF_CALL_5(bpf_tc_skc_lookup_tcp, struct sk_buff *, skb,
6864 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6865 {
6866 	struct net_device *dev = skb->dev;
6867 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6868 	struct net *caller_net = dev_net(dev);
6869 
6870 	return (unsigned long)__bpf_skc_lookup(skb, tuple, len, caller_net,
6871 					       ifindex, IPPROTO_TCP, netns_id,
6872 					       flags, sdif);
6873 }
6874 
6875 static const struct bpf_func_proto bpf_tc_skc_lookup_tcp_proto = {
6876 	.func		= bpf_tc_skc_lookup_tcp,
6877 	.gpl_only	= false,
6878 	.pkt_access	= true,
6879 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
6880 	.arg1_type	= ARG_PTR_TO_CTX,
6881 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6882 	.arg3_type	= ARG_CONST_SIZE,
6883 	.arg4_type	= ARG_ANYTHING,
6884 	.arg5_type	= ARG_ANYTHING,
6885 };
6886 
BPF_CALL_5(bpf_tc_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6887 BPF_CALL_5(bpf_tc_sk_lookup_tcp, struct sk_buff *, skb,
6888 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6889 {
6890 	struct net_device *dev = skb->dev;
6891 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6892 	struct net *caller_net = dev_net(dev);
6893 
6894 	return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
6895 					      ifindex, IPPROTO_TCP, netns_id,
6896 					      flags, sdif);
6897 }
6898 
6899 static const struct bpf_func_proto bpf_tc_sk_lookup_tcp_proto = {
6900 	.func		= bpf_tc_sk_lookup_tcp,
6901 	.gpl_only	= false,
6902 	.pkt_access	= true,
6903 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6904 	.arg1_type	= ARG_PTR_TO_CTX,
6905 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6906 	.arg3_type	= ARG_CONST_SIZE,
6907 	.arg4_type	= ARG_ANYTHING,
6908 	.arg5_type	= ARG_ANYTHING,
6909 };
6910 
BPF_CALL_5(bpf_tc_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6911 BPF_CALL_5(bpf_tc_sk_lookup_udp, struct sk_buff *, skb,
6912 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6913 {
6914 	struct net_device *dev = skb->dev;
6915 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6916 	struct net *caller_net = dev_net(dev);
6917 
6918 	return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
6919 					      ifindex, IPPROTO_UDP, netns_id,
6920 					      flags, sdif);
6921 }
6922 
6923 static const struct bpf_func_proto bpf_tc_sk_lookup_udp_proto = {
6924 	.func		= bpf_tc_sk_lookup_udp,
6925 	.gpl_only	= false,
6926 	.pkt_access	= true,
6927 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6928 	.arg1_type	= ARG_PTR_TO_CTX,
6929 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6930 	.arg3_type	= ARG_CONST_SIZE,
6931 	.arg4_type	= ARG_ANYTHING,
6932 	.arg5_type	= ARG_ANYTHING,
6933 };
6934 
BPF_CALL_1(bpf_sk_release,struct sock *,sk)6935 BPF_CALL_1(bpf_sk_release, struct sock *, sk)
6936 {
6937 	if (sk && sk_is_refcounted(sk))
6938 		sock_gen_put(sk);
6939 	return 0;
6940 }
6941 
6942 static const struct bpf_func_proto bpf_sk_release_proto = {
6943 	.func		= bpf_sk_release,
6944 	.gpl_only	= false,
6945 	.ret_type	= RET_INTEGER,
6946 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON | OBJ_RELEASE,
6947 };
6948 
BPF_CALL_5(bpf_xdp_sk_lookup_udp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6949 BPF_CALL_5(bpf_xdp_sk_lookup_udp, struct xdp_buff *, ctx,
6950 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6951 {
6952 	struct net_device *dev = ctx->rxq->dev;
6953 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6954 	struct net *caller_net = dev_net(dev);
6955 
6956 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6957 					      ifindex, IPPROTO_UDP, netns_id,
6958 					      flags, sdif);
6959 }
6960 
6961 static const struct bpf_func_proto bpf_xdp_sk_lookup_udp_proto = {
6962 	.func           = bpf_xdp_sk_lookup_udp,
6963 	.gpl_only       = false,
6964 	.pkt_access     = true,
6965 	.ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
6966 	.arg1_type      = ARG_PTR_TO_CTX,
6967 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6968 	.arg3_type      = ARG_CONST_SIZE,
6969 	.arg4_type      = ARG_ANYTHING,
6970 	.arg5_type      = ARG_ANYTHING,
6971 };
6972 
BPF_CALL_5(bpf_xdp_skc_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6973 BPF_CALL_5(bpf_xdp_skc_lookup_tcp, struct xdp_buff *, ctx,
6974 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6975 {
6976 	struct net_device *dev = ctx->rxq->dev;
6977 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6978 	struct net *caller_net = dev_net(dev);
6979 
6980 	return (unsigned long)__bpf_skc_lookup(NULL, tuple, len, caller_net,
6981 					       ifindex, IPPROTO_TCP, netns_id,
6982 					       flags, sdif);
6983 }
6984 
6985 static const struct bpf_func_proto bpf_xdp_skc_lookup_tcp_proto = {
6986 	.func           = bpf_xdp_skc_lookup_tcp,
6987 	.gpl_only       = false,
6988 	.pkt_access     = true,
6989 	.ret_type       = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6990 	.arg1_type      = ARG_PTR_TO_CTX,
6991 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6992 	.arg3_type      = ARG_CONST_SIZE,
6993 	.arg4_type      = ARG_ANYTHING,
6994 	.arg5_type      = ARG_ANYTHING,
6995 };
6996 
BPF_CALL_5(bpf_xdp_sk_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6997 BPF_CALL_5(bpf_xdp_sk_lookup_tcp, struct xdp_buff *, ctx,
6998 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6999 {
7000 	struct net_device *dev = ctx->rxq->dev;
7001 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
7002 	struct net *caller_net = dev_net(dev);
7003 
7004 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
7005 					      ifindex, IPPROTO_TCP, netns_id,
7006 					      flags, sdif);
7007 }
7008 
7009 static const struct bpf_func_proto bpf_xdp_sk_lookup_tcp_proto = {
7010 	.func           = bpf_xdp_sk_lookup_tcp,
7011 	.gpl_only       = false,
7012 	.pkt_access     = true,
7013 	.ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
7014 	.arg1_type      = ARG_PTR_TO_CTX,
7015 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
7016 	.arg3_type      = ARG_CONST_SIZE,
7017 	.arg4_type      = ARG_ANYTHING,
7018 	.arg5_type      = ARG_ANYTHING,
7019 };
7020 
BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)7021 BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
7022 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
7023 {
7024 	return (unsigned long)__bpf_skc_lookup(NULL, tuple, len,
7025 					       sock_net(ctx->sk), 0,
7026 					       IPPROTO_TCP, netns_id, flags,
7027 					       -1);
7028 }
7029 
7030 static const struct bpf_func_proto bpf_sock_addr_skc_lookup_tcp_proto = {
7031 	.func		= bpf_sock_addr_skc_lookup_tcp,
7032 	.gpl_only	= false,
7033 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
7034 	.arg1_type	= ARG_PTR_TO_CTX,
7035 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7036 	.arg3_type	= ARG_CONST_SIZE,
7037 	.arg4_type	= ARG_ANYTHING,
7038 	.arg5_type	= ARG_ANYTHING,
7039 };
7040 
BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)7041 BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
7042 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
7043 {
7044 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
7045 					      sock_net(ctx->sk), 0, IPPROTO_TCP,
7046 					      netns_id, flags, -1);
7047 }
7048 
7049 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = {
7050 	.func		= bpf_sock_addr_sk_lookup_tcp,
7051 	.gpl_only	= false,
7052 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
7053 	.arg1_type	= ARG_PTR_TO_CTX,
7054 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7055 	.arg3_type	= ARG_CONST_SIZE,
7056 	.arg4_type	= ARG_ANYTHING,
7057 	.arg5_type	= ARG_ANYTHING,
7058 };
7059 
BPF_CALL_5(bpf_sock_addr_sk_lookup_udp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)7060 BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx,
7061 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
7062 {
7063 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
7064 					      sock_net(ctx->sk), 0, IPPROTO_UDP,
7065 					      netns_id, flags, -1);
7066 }
7067 
7068 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = {
7069 	.func		= bpf_sock_addr_sk_lookup_udp,
7070 	.gpl_only	= false,
7071 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
7072 	.arg1_type	= ARG_PTR_TO_CTX,
7073 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7074 	.arg3_type	= ARG_CONST_SIZE,
7075 	.arg4_type	= ARG_ANYTHING,
7076 	.arg5_type	= ARG_ANYTHING,
7077 };
7078 
bpf_tcp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)7079 bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
7080 				  struct bpf_insn_access_aux *info)
7081 {
7082 	if (off < 0 || off >= offsetofend(struct bpf_tcp_sock,
7083 					  icsk_retransmits))
7084 		return false;
7085 
7086 	if (off % size != 0)
7087 		return false;
7088 
7089 	switch (off) {
7090 	case offsetof(struct bpf_tcp_sock, bytes_received):
7091 	case offsetof(struct bpf_tcp_sock, bytes_acked):
7092 		return size == sizeof(__u64);
7093 	default:
7094 		return size == sizeof(__u32);
7095 	}
7096 }
7097 
bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7098 u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
7099 				    const struct bpf_insn *si,
7100 				    struct bpf_insn *insn_buf,
7101 				    struct bpf_prog *prog, u32 *target_size)
7102 {
7103 	struct bpf_insn *insn = insn_buf;
7104 
7105 #define BPF_TCP_SOCK_GET_COMMON(FIELD)					\
7106 	do {								\
7107 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, FIELD) >	\
7108 			     sizeof_field(struct bpf_tcp_sock, FIELD));	\
7109 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_sock, FIELD),\
7110 				      si->dst_reg, si->src_reg,		\
7111 				      offsetof(struct tcp_sock, FIELD)); \
7112 	} while (0)
7113 
7114 #define BPF_INET_SOCK_GET_COMMON(FIELD)					\
7115 	do {								\
7116 		BUILD_BUG_ON(sizeof_field(struct inet_connection_sock,	\
7117 					  FIELD) >			\
7118 			     sizeof_field(struct bpf_tcp_sock, FIELD));	\
7119 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			\
7120 					struct inet_connection_sock,	\
7121 					FIELD),				\
7122 				      si->dst_reg, si->src_reg,		\
7123 				      offsetof(				\
7124 					struct inet_connection_sock,	\
7125 					FIELD));			\
7126 	} while (0)
7127 
7128 	BTF_TYPE_EMIT(struct bpf_tcp_sock);
7129 
7130 	switch (si->off) {
7131 	case offsetof(struct bpf_tcp_sock, rtt_min):
7132 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
7133 			     sizeof(struct minmax));
7134 		BUILD_BUG_ON(sizeof(struct minmax) <
7135 			     sizeof(struct minmax_sample));
7136 
7137 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7138 				      offsetof(struct tcp_sock, rtt_min) +
7139 				      offsetof(struct minmax_sample, v));
7140 		break;
7141 	case offsetof(struct bpf_tcp_sock, snd_cwnd):
7142 		BPF_TCP_SOCK_GET_COMMON(snd_cwnd);
7143 		break;
7144 	case offsetof(struct bpf_tcp_sock, srtt_us):
7145 		BPF_TCP_SOCK_GET_COMMON(srtt_us);
7146 		break;
7147 	case offsetof(struct bpf_tcp_sock, snd_ssthresh):
7148 		BPF_TCP_SOCK_GET_COMMON(snd_ssthresh);
7149 		break;
7150 	case offsetof(struct bpf_tcp_sock, rcv_nxt):
7151 		BPF_TCP_SOCK_GET_COMMON(rcv_nxt);
7152 		break;
7153 	case offsetof(struct bpf_tcp_sock, snd_nxt):
7154 		BPF_TCP_SOCK_GET_COMMON(snd_nxt);
7155 		break;
7156 	case offsetof(struct bpf_tcp_sock, snd_una):
7157 		BPF_TCP_SOCK_GET_COMMON(snd_una);
7158 		break;
7159 	case offsetof(struct bpf_tcp_sock, mss_cache):
7160 		BPF_TCP_SOCK_GET_COMMON(mss_cache);
7161 		break;
7162 	case offsetof(struct bpf_tcp_sock, ecn_flags):
7163 		BPF_TCP_SOCK_GET_COMMON(ecn_flags);
7164 		break;
7165 	case offsetof(struct bpf_tcp_sock, rate_delivered):
7166 		BPF_TCP_SOCK_GET_COMMON(rate_delivered);
7167 		break;
7168 	case offsetof(struct bpf_tcp_sock, rate_interval_us):
7169 		BPF_TCP_SOCK_GET_COMMON(rate_interval_us);
7170 		break;
7171 	case offsetof(struct bpf_tcp_sock, packets_out):
7172 		BPF_TCP_SOCK_GET_COMMON(packets_out);
7173 		break;
7174 	case offsetof(struct bpf_tcp_sock, retrans_out):
7175 		BPF_TCP_SOCK_GET_COMMON(retrans_out);
7176 		break;
7177 	case offsetof(struct bpf_tcp_sock, total_retrans):
7178 		BPF_TCP_SOCK_GET_COMMON(total_retrans);
7179 		break;
7180 	case offsetof(struct bpf_tcp_sock, segs_in):
7181 		BPF_TCP_SOCK_GET_COMMON(segs_in);
7182 		break;
7183 	case offsetof(struct bpf_tcp_sock, data_segs_in):
7184 		BPF_TCP_SOCK_GET_COMMON(data_segs_in);
7185 		break;
7186 	case offsetof(struct bpf_tcp_sock, segs_out):
7187 		BPF_TCP_SOCK_GET_COMMON(segs_out);
7188 		break;
7189 	case offsetof(struct bpf_tcp_sock, data_segs_out):
7190 		BPF_TCP_SOCK_GET_COMMON(data_segs_out);
7191 		break;
7192 	case offsetof(struct bpf_tcp_sock, lost_out):
7193 		BPF_TCP_SOCK_GET_COMMON(lost_out);
7194 		break;
7195 	case offsetof(struct bpf_tcp_sock, sacked_out):
7196 		BPF_TCP_SOCK_GET_COMMON(sacked_out);
7197 		break;
7198 	case offsetof(struct bpf_tcp_sock, bytes_received):
7199 		BPF_TCP_SOCK_GET_COMMON(bytes_received);
7200 		break;
7201 	case offsetof(struct bpf_tcp_sock, bytes_acked):
7202 		BPF_TCP_SOCK_GET_COMMON(bytes_acked);
7203 		break;
7204 	case offsetof(struct bpf_tcp_sock, dsack_dups):
7205 		BPF_TCP_SOCK_GET_COMMON(dsack_dups);
7206 		break;
7207 	case offsetof(struct bpf_tcp_sock, delivered):
7208 		BPF_TCP_SOCK_GET_COMMON(delivered);
7209 		break;
7210 	case offsetof(struct bpf_tcp_sock, delivered_ce):
7211 		BPF_TCP_SOCK_GET_COMMON(delivered_ce);
7212 		break;
7213 	case offsetof(struct bpf_tcp_sock, icsk_retransmits):
7214 		BPF_INET_SOCK_GET_COMMON(icsk_retransmits);
7215 		break;
7216 	}
7217 
7218 	return insn - insn_buf;
7219 }
7220 
BPF_CALL_1(bpf_tcp_sock,struct sock *,sk)7221 BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
7222 {
7223 	if (sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
7224 		return (unsigned long)sk;
7225 
7226 	return (unsigned long)NULL;
7227 }
7228 
7229 const struct bpf_func_proto bpf_tcp_sock_proto = {
7230 	.func		= bpf_tcp_sock,
7231 	.gpl_only	= false,
7232 	.ret_type	= RET_PTR_TO_TCP_SOCK_OR_NULL,
7233 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
7234 };
7235 
BPF_CALL_1(bpf_get_listener_sock,struct sock *,sk)7236 BPF_CALL_1(bpf_get_listener_sock, struct sock *, sk)
7237 {
7238 	sk = sk_to_full_sk(sk);
7239 
7240 	if (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_RCU_FREE))
7241 		return (unsigned long)sk;
7242 
7243 	return (unsigned long)NULL;
7244 }
7245 
7246 static const struct bpf_func_proto bpf_get_listener_sock_proto = {
7247 	.func		= bpf_get_listener_sock,
7248 	.gpl_only	= false,
7249 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
7250 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
7251 };
7252 
BPF_CALL_1(bpf_skb_ecn_set_ce,struct sk_buff *,skb)7253 BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb)
7254 {
7255 	unsigned int iphdr_len;
7256 
7257 	switch (skb_protocol(skb, true)) {
7258 	case cpu_to_be16(ETH_P_IP):
7259 		iphdr_len = sizeof(struct iphdr);
7260 		break;
7261 	case cpu_to_be16(ETH_P_IPV6):
7262 		iphdr_len = sizeof(struct ipv6hdr);
7263 		break;
7264 	default:
7265 		return 0;
7266 	}
7267 
7268 	if (skb_headlen(skb) < iphdr_len)
7269 		return 0;
7270 
7271 	if (skb_cloned(skb) && !skb_clone_writable(skb, iphdr_len))
7272 		return 0;
7273 
7274 	return INET_ECN_set_ce(skb);
7275 }
7276 
bpf_xdp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)7277 bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
7278 				  struct bpf_insn_access_aux *info)
7279 {
7280 	if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id))
7281 		return false;
7282 
7283 	if (off % size != 0)
7284 		return false;
7285 
7286 	switch (off) {
7287 	default:
7288 		return size == sizeof(__u32);
7289 	}
7290 }
7291 
bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7292 u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
7293 				    const struct bpf_insn *si,
7294 				    struct bpf_insn *insn_buf,
7295 				    struct bpf_prog *prog, u32 *target_size)
7296 {
7297 	struct bpf_insn *insn = insn_buf;
7298 
7299 #define BPF_XDP_SOCK_GET(FIELD)						\
7300 	do {								\
7301 		BUILD_BUG_ON(sizeof_field(struct xdp_sock, FIELD) >	\
7302 			     sizeof_field(struct bpf_xdp_sock, FIELD));	\
7303 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\
7304 				      si->dst_reg, si->src_reg,		\
7305 				      offsetof(struct xdp_sock, FIELD)); \
7306 	} while (0)
7307 
7308 	switch (si->off) {
7309 	case offsetof(struct bpf_xdp_sock, queue_id):
7310 		BPF_XDP_SOCK_GET(queue_id);
7311 		break;
7312 	}
7313 
7314 	return insn - insn_buf;
7315 }
7316 
7317 static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = {
7318 	.func           = bpf_skb_ecn_set_ce,
7319 	.gpl_only       = false,
7320 	.ret_type       = RET_INTEGER,
7321 	.arg1_type      = ARG_PTR_TO_CTX,
7322 };
7323 
BPF_CALL_5(bpf_tcp_check_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7324 BPF_CALL_5(bpf_tcp_check_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7325 	   struct tcphdr *, th, u32, th_len)
7326 {
7327 #ifdef CONFIG_SYN_COOKIES
7328 	u32 cookie;
7329 	int ret;
7330 
7331 	if (unlikely(!sk || th_len < sizeof(*th)))
7332 		return -EINVAL;
7333 
7334 	/* sk_listener() allows TCP_NEW_SYN_RECV, which makes no sense here. */
7335 	if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7336 		return -EINVAL;
7337 
7338 	if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7339 		return -EINVAL;
7340 
7341 	if (!th->ack || th->rst || th->syn)
7342 		return -ENOENT;
7343 
7344 	if (unlikely(iph_len < sizeof(struct iphdr)))
7345 		return -EINVAL;
7346 
7347 	if (tcp_synq_no_recent_overflow(sk))
7348 		return -ENOENT;
7349 
7350 	cookie = ntohl(th->ack_seq) - 1;
7351 
7352 	/* Both struct iphdr and struct ipv6hdr have the version field at the
7353 	 * same offset so we can cast to the shorter header (struct iphdr).
7354 	 */
7355 	switch (((struct iphdr *)iph)->version) {
7356 	case 4:
7357 		if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7358 			return -EINVAL;
7359 
7360 		ret = __cookie_v4_check((struct iphdr *)iph, th, cookie);
7361 		break;
7362 
7363 #if IS_BUILTIN(CONFIG_IPV6)
7364 	case 6:
7365 		if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7366 			return -EINVAL;
7367 
7368 		if (sk->sk_family != AF_INET6)
7369 			return -EINVAL;
7370 
7371 		ret = __cookie_v6_check((struct ipv6hdr *)iph, th, cookie);
7372 		break;
7373 #endif /* CONFIG_IPV6 */
7374 
7375 	default:
7376 		return -EPROTONOSUPPORT;
7377 	}
7378 
7379 	if (ret > 0)
7380 		return 0;
7381 
7382 	return -ENOENT;
7383 #else
7384 	return -ENOTSUPP;
7385 #endif
7386 }
7387 
7388 static const struct bpf_func_proto bpf_tcp_check_syncookie_proto = {
7389 	.func		= bpf_tcp_check_syncookie,
7390 	.gpl_only	= true,
7391 	.pkt_access	= true,
7392 	.ret_type	= RET_INTEGER,
7393 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7394 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7395 	.arg3_type	= ARG_CONST_SIZE,
7396 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7397 	.arg5_type	= ARG_CONST_SIZE,
7398 };
7399 
BPF_CALL_5(bpf_tcp_gen_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7400 BPF_CALL_5(bpf_tcp_gen_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7401 	   struct tcphdr *, th, u32, th_len)
7402 {
7403 #ifdef CONFIG_SYN_COOKIES
7404 	u32 cookie;
7405 	u16 mss;
7406 
7407 	if (unlikely(!sk || th_len < sizeof(*th) || th_len != th->doff * 4))
7408 		return -EINVAL;
7409 
7410 	if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7411 		return -EINVAL;
7412 
7413 	if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7414 		return -ENOENT;
7415 
7416 	if (!th->syn || th->ack || th->fin || th->rst)
7417 		return -EINVAL;
7418 
7419 	if (unlikely(iph_len < sizeof(struct iphdr)))
7420 		return -EINVAL;
7421 
7422 	/* Both struct iphdr and struct ipv6hdr have the version field at the
7423 	 * same offset so we can cast to the shorter header (struct iphdr).
7424 	 */
7425 	switch (((struct iphdr *)iph)->version) {
7426 	case 4:
7427 		if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7428 			return -EINVAL;
7429 
7430 		mss = tcp_v4_get_syncookie(sk, iph, th, &cookie);
7431 		break;
7432 
7433 #if IS_BUILTIN(CONFIG_IPV6)
7434 	case 6:
7435 		if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7436 			return -EINVAL;
7437 
7438 		if (sk->sk_family != AF_INET6)
7439 			return -EINVAL;
7440 
7441 		mss = tcp_v6_get_syncookie(sk, iph, th, &cookie);
7442 		break;
7443 #endif /* CONFIG_IPV6 */
7444 
7445 	default:
7446 		return -EPROTONOSUPPORT;
7447 	}
7448 	if (mss == 0)
7449 		return -ENOENT;
7450 
7451 	return cookie | ((u64)mss << 32);
7452 #else
7453 	return -EOPNOTSUPP;
7454 #endif /* CONFIG_SYN_COOKIES */
7455 }
7456 
7457 static const struct bpf_func_proto bpf_tcp_gen_syncookie_proto = {
7458 	.func		= bpf_tcp_gen_syncookie,
7459 	.gpl_only	= true, /* __cookie_v*_init_sequence() is GPL */
7460 	.pkt_access	= true,
7461 	.ret_type	= RET_INTEGER,
7462 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7463 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7464 	.arg3_type	= ARG_CONST_SIZE,
7465 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7466 	.arg5_type	= ARG_CONST_SIZE,
7467 };
7468 
BPF_CALL_3(bpf_sk_assign,struct sk_buff *,skb,struct sock *,sk,u64,flags)7469 BPF_CALL_3(bpf_sk_assign, struct sk_buff *, skb, struct sock *, sk, u64, flags)
7470 {
7471 	if (!sk || flags != 0)
7472 		return -EINVAL;
7473 	if (!skb_at_tc_ingress(skb))
7474 		return -EOPNOTSUPP;
7475 	if (unlikely(dev_net(skb->dev) != sock_net(sk)))
7476 		return -ENETUNREACH;
7477 	if (sk_unhashed(sk))
7478 		return -EOPNOTSUPP;
7479 	if (sk_is_refcounted(sk) &&
7480 	    unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
7481 		return -ENOENT;
7482 
7483 	skb_orphan(skb);
7484 	skb->sk = sk;
7485 	skb->destructor = sock_pfree;
7486 
7487 	return 0;
7488 }
7489 
7490 static const struct bpf_func_proto bpf_sk_assign_proto = {
7491 	.func		= bpf_sk_assign,
7492 	.gpl_only	= false,
7493 	.ret_type	= RET_INTEGER,
7494 	.arg1_type      = ARG_PTR_TO_CTX,
7495 	.arg2_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7496 	.arg3_type	= ARG_ANYTHING,
7497 };
7498 
bpf_search_tcp_opt(const u8 * op,const u8 * opend,u8 search_kind,const u8 * magic,u8 magic_len,bool * eol)7499 static const u8 *bpf_search_tcp_opt(const u8 *op, const u8 *opend,
7500 				    u8 search_kind, const u8 *magic,
7501 				    u8 magic_len, bool *eol)
7502 {
7503 	u8 kind, kind_len;
7504 
7505 	*eol = false;
7506 
7507 	while (op < opend) {
7508 		kind = op[0];
7509 
7510 		if (kind == TCPOPT_EOL) {
7511 			*eol = true;
7512 			return ERR_PTR(-ENOMSG);
7513 		} else if (kind == TCPOPT_NOP) {
7514 			op++;
7515 			continue;
7516 		}
7517 
7518 		if (opend - op < 2 || opend - op < op[1] || op[1] < 2)
7519 			/* Something is wrong in the received header.
7520 			 * Follow the TCP stack's tcp_parse_options()
7521 			 * and just bail here.
7522 			 */
7523 			return ERR_PTR(-EFAULT);
7524 
7525 		kind_len = op[1];
7526 		if (search_kind == kind) {
7527 			if (!magic_len)
7528 				return op;
7529 
7530 			if (magic_len > kind_len - 2)
7531 				return ERR_PTR(-ENOMSG);
7532 
7533 			if (!memcmp(&op[2], magic, magic_len))
7534 				return op;
7535 		}
7536 
7537 		op += kind_len;
7538 	}
7539 
7540 	return ERR_PTR(-ENOMSG);
7541 }
7542 
BPF_CALL_4(bpf_sock_ops_load_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,void *,search_res,u32,len,u64,flags)7543 BPF_CALL_4(bpf_sock_ops_load_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7544 	   void *, search_res, u32, len, u64, flags)
7545 {
7546 	bool eol, load_syn = flags & BPF_LOAD_HDR_OPT_TCP_SYN;
7547 	const u8 *op, *opend, *magic, *search = search_res;
7548 	u8 search_kind, search_len, copy_len, magic_len;
7549 	int ret;
7550 
7551 	/* 2 byte is the minimal option len except TCPOPT_NOP and
7552 	 * TCPOPT_EOL which are useless for the bpf prog to learn
7553 	 * and this helper disallow loading them also.
7554 	 */
7555 	if (len < 2 || flags & ~BPF_LOAD_HDR_OPT_TCP_SYN)
7556 		return -EINVAL;
7557 
7558 	search_kind = search[0];
7559 	search_len = search[1];
7560 
7561 	if (search_len > len || search_kind == TCPOPT_NOP ||
7562 	    search_kind == TCPOPT_EOL)
7563 		return -EINVAL;
7564 
7565 	if (search_kind == TCPOPT_EXP || search_kind == 253) {
7566 		/* 16 or 32 bit magic.  +2 for kind and kind length */
7567 		if (search_len != 4 && search_len != 6)
7568 			return -EINVAL;
7569 		magic = &search[2];
7570 		magic_len = search_len - 2;
7571 	} else {
7572 		if (search_len)
7573 			return -EINVAL;
7574 		magic = NULL;
7575 		magic_len = 0;
7576 	}
7577 
7578 	if (load_syn) {
7579 		ret = bpf_sock_ops_get_syn(bpf_sock, TCP_BPF_SYN, &op);
7580 		if (ret < 0)
7581 			return ret;
7582 
7583 		opend = op + ret;
7584 		op += sizeof(struct tcphdr);
7585 	} else {
7586 		if (!bpf_sock->skb ||
7587 		    bpf_sock->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7588 			/* This bpf_sock->op cannot call this helper */
7589 			return -EPERM;
7590 
7591 		opend = bpf_sock->skb_data_end;
7592 		op = bpf_sock->skb->data + sizeof(struct tcphdr);
7593 	}
7594 
7595 	op = bpf_search_tcp_opt(op, opend, search_kind, magic, magic_len,
7596 				&eol);
7597 	if (IS_ERR(op))
7598 		return PTR_ERR(op);
7599 
7600 	copy_len = op[1];
7601 	ret = copy_len;
7602 	if (copy_len > len) {
7603 		ret = -ENOSPC;
7604 		copy_len = len;
7605 	}
7606 
7607 	memcpy(search_res, op, copy_len);
7608 	return ret;
7609 }
7610 
7611 static const struct bpf_func_proto bpf_sock_ops_load_hdr_opt_proto = {
7612 	.func		= bpf_sock_ops_load_hdr_opt,
7613 	.gpl_only	= false,
7614 	.ret_type	= RET_INTEGER,
7615 	.arg1_type	= ARG_PTR_TO_CTX,
7616 	.arg2_type	= ARG_PTR_TO_MEM | MEM_WRITE,
7617 	.arg3_type	= ARG_CONST_SIZE,
7618 	.arg4_type	= ARG_ANYTHING,
7619 };
7620 
BPF_CALL_4(bpf_sock_ops_store_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,const void *,from,u32,len,u64,flags)7621 BPF_CALL_4(bpf_sock_ops_store_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7622 	   const void *, from, u32, len, u64, flags)
7623 {
7624 	u8 new_kind, new_kind_len, magic_len = 0, *opend;
7625 	const u8 *op, *new_op, *magic = NULL;
7626 	struct sk_buff *skb;
7627 	bool eol;
7628 
7629 	if (bpf_sock->op != BPF_SOCK_OPS_WRITE_HDR_OPT_CB)
7630 		return -EPERM;
7631 
7632 	if (len < 2 || flags)
7633 		return -EINVAL;
7634 
7635 	new_op = from;
7636 	new_kind = new_op[0];
7637 	new_kind_len = new_op[1];
7638 
7639 	if (new_kind_len > len || new_kind == TCPOPT_NOP ||
7640 	    new_kind == TCPOPT_EOL)
7641 		return -EINVAL;
7642 
7643 	if (new_kind_len > bpf_sock->remaining_opt_len)
7644 		return -ENOSPC;
7645 
7646 	/* 253 is another experimental kind */
7647 	if (new_kind == TCPOPT_EXP || new_kind == 253)  {
7648 		if (new_kind_len < 4)
7649 			return -EINVAL;
7650 		/* Match for the 2 byte magic also.
7651 		 * RFC 6994: the magic could be 2 or 4 bytes.
7652 		 * Hence, matching by 2 byte only is on the
7653 		 * conservative side but it is the right
7654 		 * thing to do for the 'search-for-duplication'
7655 		 * purpose.
7656 		 */
7657 		magic = &new_op[2];
7658 		magic_len = 2;
7659 	}
7660 
7661 	/* Check for duplication */
7662 	skb = bpf_sock->skb;
7663 	op = skb->data + sizeof(struct tcphdr);
7664 	opend = bpf_sock->skb_data_end;
7665 
7666 	op = bpf_search_tcp_opt(op, opend, new_kind, magic, magic_len,
7667 				&eol);
7668 	if (!IS_ERR(op))
7669 		return -EEXIST;
7670 
7671 	if (PTR_ERR(op) != -ENOMSG)
7672 		return PTR_ERR(op);
7673 
7674 	if (eol)
7675 		/* The option has been ended.  Treat it as no more
7676 		 * header option can be written.
7677 		 */
7678 		return -ENOSPC;
7679 
7680 	/* No duplication found.  Store the header option. */
7681 	memcpy(opend, from, new_kind_len);
7682 
7683 	bpf_sock->remaining_opt_len -= new_kind_len;
7684 	bpf_sock->skb_data_end += new_kind_len;
7685 
7686 	return 0;
7687 }
7688 
7689 static const struct bpf_func_proto bpf_sock_ops_store_hdr_opt_proto = {
7690 	.func		= bpf_sock_ops_store_hdr_opt,
7691 	.gpl_only	= false,
7692 	.ret_type	= RET_INTEGER,
7693 	.arg1_type	= ARG_PTR_TO_CTX,
7694 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7695 	.arg3_type	= ARG_CONST_SIZE,
7696 	.arg4_type	= ARG_ANYTHING,
7697 };
7698 
BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,u32,len,u64,flags)7699 BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7700 	   u32, len, u64, flags)
7701 {
7702 	if (bpf_sock->op != BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7703 		return -EPERM;
7704 
7705 	if (flags || len < 2)
7706 		return -EINVAL;
7707 
7708 	if (len > bpf_sock->remaining_opt_len)
7709 		return -ENOSPC;
7710 
7711 	bpf_sock->remaining_opt_len -= len;
7712 
7713 	return 0;
7714 }
7715 
7716 static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = {
7717 	.func		= bpf_sock_ops_reserve_hdr_opt,
7718 	.gpl_only	= false,
7719 	.ret_type	= RET_INTEGER,
7720 	.arg1_type	= ARG_PTR_TO_CTX,
7721 	.arg2_type	= ARG_ANYTHING,
7722 	.arg3_type	= ARG_ANYTHING,
7723 };
7724 
BPF_CALL_3(bpf_skb_set_tstamp,struct sk_buff *,skb,u64,tstamp,u32,tstamp_type)7725 BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb,
7726 	   u64, tstamp, u32, tstamp_type)
7727 {
7728 	/* skb_clear_delivery_time() is done for inet protocol */
7729 	if (skb->protocol != htons(ETH_P_IP) &&
7730 	    skb->protocol != htons(ETH_P_IPV6))
7731 		return -EOPNOTSUPP;
7732 
7733 	switch (tstamp_type) {
7734 	case BPF_SKB_TSTAMP_DELIVERY_MONO:
7735 		if (!tstamp)
7736 			return -EINVAL;
7737 		skb->tstamp = tstamp;
7738 		skb->tstamp_type = SKB_CLOCK_MONOTONIC;
7739 		break;
7740 	case BPF_SKB_TSTAMP_UNSPEC:
7741 		if (tstamp)
7742 			return -EINVAL;
7743 		skb->tstamp = 0;
7744 		skb->tstamp_type = SKB_CLOCK_REALTIME;
7745 		break;
7746 	default:
7747 		return -EINVAL;
7748 	}
7749 
7750 	return 0;
7751 }
7752 
7753 static const struct bpf_func_proto bpf_skb_set_tstamp_proto = {
7754 	.func           = bpf_skb_set_tstamp,
7755 	.gpl_only       = false,
7756 	.ret_type       = RET_INTEGER,
7757 	.arg1_type      = ARG_PTR_TO_CTX,
7758 	.arg2_type      = ARG_ANYTHING,
7759 	.arg3_type      = ARG_ANYTHING,
7760 };
7761 
7762 #ifdef CONFIG_SYN_COOKIES
BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv4,struct iphdr *,iph,struct tcphdr *,th,u32,th_len)7763 BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv4, struct iphdr *, iph,
7764 	   struct tcphdr *, th, u32, th_len)
7765 {
7766 	u32 cookie;
7767 	u16 mss;
7768 
7769 	if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
7770 		return -EINVAL;
7771 
7772 	mss = tcp_parse_mss_option(th, 0) ?: TCP_MSS_DEFAULT;
7773 	cookie = __cookie_v4_init_sequence(iph, th, &mss);
7774 
7775 	return cookie | ((u64)mss << 32);
7776 }
7777 
7778 static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv4_proto = {
7779 	.func		= bpf_tcp_raw_gen_syncookie_ipv4,
7780 	.gpl_only	= true, /* __cookie_v4_init_sequence() is GPL */
7781 	.pkt_access	= true,
7782 	.ret_type	= RET_INTEGER,
7783 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7784 	.arg1_size	= sizeof(struct iphdr),
7785 	.arg2_type	= ARG_PTR_TO_MEM,
7786 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
7787 };
7788 
BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv6,struct ipv6hdr *,iph,struct tcphdr *,th,u32,th_len)7789 BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv6, struct ipv6hdr *, iph,
7790 	   struct tcphdr *, th, u32, th_len)
7791 {
7792 #if IS_BUILTIN(CONFIG_IPV6)
7793 	const u16 mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) -
7794 		sizeof(struct ipv6hdr);
7795 	u32 cookie;
7796 	u16 mss;
7797 
7798 	if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
7799 		return -EINVAL;
7800 
7801 	mss = tcp_parse_mss_option(th, 0) ?: mss_clamp;
7802 	cookie = __cookie_v6_init_sequence(iph, th, &mss);
7803 
7804 	return cookie | ((u64)mss << 32);
7805 #else
7806 	return -EPROTONOSUPPORT;
7807 #endif
7808 }
7809 
7810 static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv6_proto = {
7811 	.func		= bpf_tcp_raw_gen_syncookie_ipv6,
7812 	.gpl_only	= true, /* __cookie_v6_init_sequence() is GPL */
7813 	.pkt_access	= true,
7814 	.ret_type	= RET_INTEGER,
7815 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7816 	.arg1_size	= sizeof(struct ipv6hdr),
7817 	.arg2_type	= ARG_PTR_TO_MEM,
7818 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
7819 };
7820 
BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv4,struct iphdr *,iph,struct tcphdr *,th)7821 BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv4, struct iphdr *, iph,
7822 	   struct tcphdr *, th)
7823 {
7824 	u32 cookie = ntohl(th->ack_seq) - 1;
7825 
7826 	if (__cookie_v4_check(iph, th, cookie) > 0)
7827 		return 0;
7828 
7829 	return -EACCES;
7830 }
7831 
7832 static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv4_proto = {
7833 	.func		= bpf_tcp_raw_check_syncookie_ipv4,
7834 	.gpl_only	= true, /* __cookie_v4_check is GPL */
7835 	.pkt_access	= true,
7836 	.ret_type	= RET_INTEGER,
7837 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7838 	.arg1_size	= sizeof(struct iphdr),
7839 	.arg2_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7840 	.arg2_size	= sizeof(struct tcphdr),
7841 };
7842 
BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv6,struct ipv6hdr *,iph,struct tcphdr *,th)7843 BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv6, struct ipv6hdr *, iph,
7844 	   struct tcphdr *, th)
7845 {
7846 #if IS_BUILTIN(CONFIG_IPV6)
7847 	u32 cookie = ntohl(th->ack_seq) - 1;
7848 
7849 	if (__cookie_v6_check(iph, th, cookie) > 0)
7850 		return 0;
7851 
7852 	return -EACCES;
7853 #else
7854 	return -EPROTONOSUPPORT;
7855 #endif
7856 }
7857 
7858 static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv6_proto = {
7859 	.func		= bpf_tcp_raw_check_syncookie_ipv6,
7860 	.gpl_only	= true, /* __cookie_v6_check is GPL */
7861 	.pkt_access	= true,
7862 	.ret_type	= RET_INTEGER,
7863 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7864 	.arg1_size	= sizeof(struct ipv6hdr),
7865 	.arg2_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7866 	.arg2_size	= sizeof(struct tcphdr),
7867 };
7868 #endif /* CONFIG_SYN_COOKIES */
7869 
7870 #endif /* CONFIG_INET */
7871 
bpf_helper_changes_pkt_data(enum bpf_func_id func_id)7872 bool bpf_helper_changes_pkt_data(enum bpf_func_id func_id)
7873 {
7874 	switch (func_id) {
7875 	case BPF_FUNC_clone_redirect:
7876 	case BPF_FUNC_l3_csum_replace:
7877 	case BPF_FUNC_l4_csum_replace:
7878 	case BPF_FUNC_lwt_push_encap:
7879 	case BPF_FUNC_lwt_seg6_action:
7880 	case BPF_FUNC_lwt_seg6_adjust_srh:
7881 	case BPF_FUNC_lwt_seg6_store_bytes:
7882 	case BPF_FUNC_msg_pop_data:
7883 	case BPF_FUNC_msg_pull_data:
7884 	case BPF_FUNC_msg_push_data:
7885 	case BPF_FUNC_skb_adjust_room:
7886 	case BPF_FUNC_skb_change_head:
7887 	case BPF_FUNC_skb_change_proto:
7888 	case BPF_FUNC_skb_change_tail:
7889 	case BPF_FUNC_skb_pull_data:
7890 	case BPF_FUNC_skb_store_bytes:
7891 	case BPF_FUNC_skb_vlan_pop:
7892 	case BPF_FUNC_skb_vlan_push:
7893 	case BPF_FUNC_store_hdr_opt:
7894 	case BPF_FUNC_xdp_adjust_head:
7895 	case BPF_FUNC_xdp_adjust_meta:
7896 	case BPF_FUNC_xdp_adjust_tail:
7897 	/* tail-called program could call any of the above */
7898 	case BPF_FUNC_tail_call:
7899 		return true;
7900 	default:
7901 		return false;
7902 	}
7903 }
7904 
7905 const struct bpf_func_proto bpf_event_output_data_proto __weak;
7906 const struct bpf_func_proto bpf_sk_storage_get_cg_sock_proto __weak;
7907 
7908 static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7909 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7910 {
7911 	const struct bpf_func_proto *func_proto;
7912 
7913 	func_proto = cgroup_common_func_proto(func_id, prog);
7914 	if (func_proto)
7915 		return func_proto;
7916 
7917 	func_proto = cgroup_current_func_proto(func_id, prog);
7918 	if (func_proto)
7919 		return func_proto;
7920 
7921 	switch (func_id) {
7922 	case BPF_FUNC_get_socket_cookie:
7923 		return &bpf_get_socket_cookie_sock_proto;
7924 	case BPF_FUNC_get_netns_cookie:
7925 		return &bpf_get_netns_cookie_sock_proto;
7926 	case BPF_FUNC_perf_event_output:
7927 		return &bpf_event_output_data_proto;
7928 	case BPF_FUNC_sk_storage_get:
7929 		return &bpf_sk_storage_get_cg_sock_proto;
7930 	case BPF_FUNC_ktime_get_coarse_ns:
7931 		return &bpf_ktime_get_coarse_ns_proto;
7932 	default:
7933 		return bpf_base_func_proto(func_id);
7934 	}
7935 }
7936 
7937 static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7938 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7939 {
7940 	const struct bpf_func_proto *func_proto;
7941 
7942 	func_proto = cgroup_common_func_proto(func_id, prog);
7943 	if (func_proto)
7944 		return func_proto;
7945 
7946 	func_proto = cgroup_current_func_proto(func_id, prog);
7947 	if (func_proto)
7948 		return func_proto;
7949 
7950 	switch (func_id) {
7951 	case BPF_FUNC_bind:
7952 		switch (prog->expected_attach_type) {
7953 		case BPF_CGROUP_INET4_CONNECT:
7954 		case BPF_CGROUP_INET6_CONNECT:
7955 			return &bpf_bind_proto;
7956 		default:
7957 			return NULL;
7958 		}
7959 	case BPF_FUNC_get_socket_cookie:
7960 		return &bpf_get_socket_cookie_sock_addr_proto;
7961 	case BPF_FUNC_get_netns_cookie:
7962 		return &bpf_get_netns_cookie_sock_addr_proto;
7963 	case BPF_FUNC_perf_event_output:
7964 		return &bpf_event_output_data_proto;
7965 #ifdef CONFIG_INET
7966 	case BPF_FUNC_sk_lookup_tcp:
7967 		return &bpf_sock_addr_sk_lookup_tcp_proto;
7968 	case BPF_FUNC_sk_lookup_udp:
7969 		return &bpf_sock_addr_sk_lookup_udp_proto;
7970 	case BPF_FUNC_sk_release:
7971 		return &bpf_sk_release_proto;
7972 	case BPF_FUNC_skc_lookup_tcp:
7973 		return &bpf_sock_addr_skc_lookup_tcp_proto;
7974 #endif /* CONFIG_INET */
7975 	case BPF_FUNC_sk_storage_get:
7976 		return &bpf_sk_storage_get_proto;
7977 	case BPF_FUNC_sk_storage_delete:
7978 		return &bpf_sk_storage_delete_proto;
7979 	case BPF_FUNC_setsockopt:
7980 		switch (prog->expected_attach_type) {
7981 		case BPF_CGROUP_INET4_BIND:
7982 		case BPF_CGROUP_INET6_BIND:
7983 		case BPF_CGROUP_INET4_CONNECT:
7984 		case BPF_CGROUP_INET6_CONNECT:
7985 		case BPF_CGROUP_UDP4_RECVMSG:
7986 		case BPF_CGROUP_UDP6_RECVMSG:
7987 		case BPF_CGROUP_UDP4_SENDMSG:
7988 		case BPF_CGROUP_UDP6_SENDMSG:
7989 		case BPF_CGROUP_INET4_GETPEERNAME:
7990 		case BPF_CGROUP_INET6_GETPEERNAME:
7991 		case BPF_CGROUP_INET4_GETSOCKNAME:
7992 		case BPF_CGROUP_INET6_GETSOCKNAME:
7993 			return &bpf_sock_addr_setsockopt_proto;
7994 		default:
7995 			return NULL;
7996 		}
7997 	case BPF_FUNC_getsockopt:
7998 		switch (prog->expected_attach_type) {
7999 		case BPF_CGROUP_INET4_BIND:
8000 		case BPF_CGROUP_INET6_BIND:
8001 		case BPF_CGROUP_INET4_CONNECT:
8002 		case BPF_CGROUP_INET6_CONNECT:
8003 		case BPF_CGROUP_UDP4_RECVMSG:
8004 		case BPF_CGROUP_UDP6_RECVMSG:
8005 		case BPF_CGROUP_UDP4_SENDMSG:
8006 		case BPF_CGROUP_UDP6_SENDMSG:
8007 		case BPF_CGROUP_INET4_GETPEERNAME:
8008 		case BPF_CGROUP_INET6_GETPEERNAME:
8009 		case BPF_CGROUP_INET4_GETSOCKNAME:
8010 		case BPF_CGROUP_INET6_GETSOCKNAME:
8011 			return &bpf_sock_addr_getsockopt_proto;
8012 		default:
8013 			return NULL;
8014 		}
8015 	default:
8016 		return bpf_sk_base_func_proto(func_id);
8017 	}
8018 }
8019 
8020 static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8021 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8022 {
8023 	switch (func_id) {
8024 	case BPF_FUNC_skb_load_bytes:
8025 		return &bpf_skb_load_bytes_proto;
8026 	case BPF_FUNC_skb_load_bytes_relative:
8027 		return &bpf_skb_load_bytes_relative_proto;
8028 	case BPF_FUNC_get_socket_cookie:
8029 		return &bpf_get_socket_cookie_proto;
8030 	case BPF_FUNC_get_socket_uid:
8031 		return &bpf_get_socket_uid_proto;
8032 	case BPF_FUNC_perf_event_output:
8033 		return &bpf_skb_event_output_proto;
8034 	default:
8035 		return bpf_sk_base_func_proto(func_id);
8036 	}
8037 }
8038 
8039 const struct bpf_func_proto bpf_sk_storage_get_proto __weak;
8040 const struct bpf_func_proto bpf_sk_storage_delete_proto __weak;
8041 
8042 static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8043 cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8044 {
8045 	const struct bpf_func_proto *func_proto;
8046 
8047 	func_proto = cgroup_common_func_proto(func_id, prog);
8048 	if (func_proto)
8049 		return func_proto;
8050 
8051 	switch (func_id) {
8052 	case BPF_FUNC_sk_fullsock:
8053 		return &bpf_sk_fullsock_proto;
8054 	case BPF_FUNC_sk_storage_get:
8055 		return &bpf_sk_storage_get_proto;
8056 	case BPF_FUNC_sk_storage_delete:
8057 		return &bpf_sk_storage_delete_proto;
8058 	case BPF_FUNC_perf_event_output:
8059 		return &bpf_skb_event_output_proto;
8060 #ifdef CONFIG_SOCK_CGROUP_DATA
8061 	case BPF_FUNC_skb_cgroup_id:
8062 		return &bpf_skb_cgroup_id_proto;
8063 	case BPF_FUNC_skb_ancestor_cgroup_id:
8064 		return &bpf_skb_ancestor_cgroup_id_proto;
8065 	case BPF_FUNC_sk_cgroup_id:
8066 		return &bpf_sk_cgroup_id_proto;
8067 	case BPF_FUNC_sk_ancestor_cgroup_id:
8068 		return &bpf_sk_ancestor_cgroup_id_proto;
8069 #endif
8070 #ifdef CONFIG_INET
8071 	case BPF_FUNC_sk_lookup_tcp:
8072 		return &bpf_sk_lookup_tcp_proto;
8073 	case BPF_FUNC_sk_lookup_udp:
8074 		return &bpf_sk_lookup_udp_proto;
8075 	case BPF_FUNC_sk_release:
8076 		return &bpf_sk_release_proto;
8077 	case BPF_FUNC_skc_lookup_tcp:
8078 		return &bpf_skc_lookup_tcp_proto;
8079 	case BPF_FUNC_tcp_sock:
8080 		return &bpf_tcp_sock_proto;
8081 	case BPF_FUNC_get_listener_sock:
8082 		return &bpf_get_listener_sock_proto;
8083 	case BPF_FUNC_skb_ecn_set_ce:
8084 		return &bpf_skb_ecn_set_ce_proto;
8085 #endif
8086 	default:
8087 		return sk_filter_func_proto(func_id, prog);
8088 	}
8089 }
8090 
8091 static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8092 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8093 {
8094 	switch (func_id) {
8095 	case BPF_FUNC_skb_store_bytes:
8096 		return &bpf_skb_store_bytes_proto;
8097 	case BPF_FUNC_skb_load_bytes:
8098 		return &bpf_skb_load_bytes_proto;
8099 	case BPF_FUNC_skb_load_bytes_relative:
8100 		return &bpf_skb_load_bytes_relative_proto;
8101 	case BPF_FUNC_skb_pull_data:
8102 		return &bpf_skb_pull_data_proto;
8103 	case BPF_FUNC_csum_diff:
8104 		return &bpf_csum_diff_proto;
8105 	case BPF_FUNC_csum_update:
8106 		return &bpf_csum_update_proto;
8107 	case BPF_FUNC_csum_level:
8108 		return &bpf_csum_level_proto;
8109 	case BPF_FUNC_l3_csum_replace:
8110 		return &bpf_l3_csum_replace_proto;
8111 	case BPF_FUNC_l4_csum_replace:
8112 		return &bpf_l4_csum_replace_proto;
8113 	case BPF_FUNC_clone_redirect:
8114 		return &bpf_clone_redirect_proto;
8115 	case BPF_FUNC_get_cgroup_classid:
8116 		return &bpf_get_cgroup_classid_proto;
8117 	case BPF_FUNC_skb_vlan_push:
8118 		return &bpf_skb_vlan_push_proto;
8119 	case BPF_FUNC_skb_vlan_pop:
8120 		return &bpf_skb_vlan_pop_proto;
8121 	case BPF_FUNC_skb_change_proto:
8122 		return &bpf_skb_change_proto_proto;
8123 	case BPF_FUNC_skb_change_type:
8124 		return &bpf_skb_change_type_proto;
8125 	case BPF_FUNC_skb_adjust_room:
8126 		return &bpf_skb_adjust_room_proto;
8127 	case BPF_FUNC_skb_change_tail:
8128 		return &bpf_skb_change_tail_proto;
8129 	case BPF_FUNC_skb_change_head:
8130 		return &bpf_skb_change_head_proto;
8131 	case BPF_FUNC_skb_get_tunnel_key:
8132 		return &bpf_skb_get_tunnel_key_proto;
8133 	case BPF_FUNC_skb_set_tunnel_key:
8134 		return bpf_get_skb_set_tunnel_proto(func_id);
8135 	case BPF_FUNC_skb_get_tunnel_opt:
8136 		return &bpf_skb_get_tunnel_opt_proto;
8137 	case BPF_FUNC_skb_set_tunnel_opt:
8138 		return bpf_get_skb_set_tunnel_proto(func_id);
8139 	case BPF_FUNC_redirect:
8140 		return &bpf_redirect_proto;
8141 	case BPF_FUNC_redirect_neigh:
8142 		return &bpf_redirect_neigh_proto;
8143 	case BPF_FUNC_redirect_peer:
8144 		return &bpf_redirect_peer_proto;
8145 	case BPF_FUNC_get_route_realm:
8146 		return &bpf_get_route_realm_proto;
8147 	case BPF_FUNC_get_hash_recalc:
8148 		return &bpf_get_hash_recalc_proto;
8149 	case BPF_FUNC_set_hash_invalid:
8150 		return &bpf_set_hash_invalid_proto;
8151 	case BPF_FUNC_set_hash:
8152 		return &bpf_set_hash_proto;
8153 	case BPF_FUNC_perf_event_output:
8154 		return &bpf_skb_event_output_proto;
8155 	case BPF_FUNC_get_smp_processor_id:
8156 		return &bpf_get_smp_processor_id_proto;
8157 	case BPF_FUNC_skb_under_cgroup:
8158 		return &bpf_skb_under_cgroup_proto;
8159 	case BPF_FUNC_get_socket_cookie:
8160 		return &bpf_get_socket_cookie_proto;
8161 	case BPF_FUNC_get_socket_uid:
8162 		return &bpf_get_socket_uid_proto;
8163 	case BPF_FUNC_fib_lookup:
8164 		return &bpf_skb_fib_lookup_proto;
8165 	case BPF_FUNC_check_mtu:
8166 		return &bpf_skb_check_mtu_proto;
8167 	case BPF_FUNC_sk_fullsock:
8168 		return &bpf_sk_fullsock_proto;
8169 	case BPF_FUNC_sk_storage_get:
8170 		return &bpf_sk_storage_get_proto;
8171 	case BPF_FUNC_sk_storage_delete:
8172 		return &bpf_sk_storage_delete_proto;
8173 #ifdef CONFIG_XFRM
8174 	case BPF_FUNC_skb_get_xfrm_state:
8175 		return &bpf_skb_get_xfrm_state_proto;
8176 #endif
8177 #ifdef CONFIG_CGROUP_NET_CLASSID
8178 	case BPF_FUNC_skb_cgroup_classid:
8179 		return &bpf_skb_cgroup_classid_proto;
8180 #endif
8181 #ifdef CONFIG_SOCK_CGROUP_DATA
8182 	case BPF_FUNC_skb_cgroup_id:
8183 		return &bpf_skb_cgroup_id_proto;
8184 	case BPF_FUNC_skb_ancestor_cgroup_id:
8185 		return &bpf_skb_ancestor_cgroup_id_proto;
8186 #endif
8187 #ifdef CONFIG_INET
8188 	case BPF_FUNC_sk_lookup_tcp:
8189 		return &bpf_tc_sk_lookup_tcp_proto;
8190 	case BPF_FUNC_sk_lookup_udp:
8191 		return &bpf_tc_sk_lookup_udp_proto;
8192 	case BPF_FUNC_sk_release:
8193 		return &bpf_sk_release_proto;
8194 	case BPF_FUNC_tcp_sock:
8195 		return &bpf_tcp_sock_proto;
8196 	case BPF_FUNC_get_listener_sock:
8197 		return &bpf_get_listener_sock_proto;
8198 	case BPF_FUNC_skc_lookup_tcp:
8199 		return &bpf_tc_skc_lookup_tcp_proto;
8200 	case BPF_FUNC_tcp_check_syncookie:
8201 		return &bpf_tcp_check_syncookie_proto;
8202 	case BPF_FUNC_skb_ecn_set_ce:
8203 		return &bpf_skb_ecn_set_ce_proto;
8204 	case BPF_FUNC_tcp_gen_syncookie:
8205 		return &bpf_tcp_gen_syncookie_proto;
8206 	case BPF_FUNC_sk_assign:
8207 		return &bpf_sk_assign_proto;
8208 	case BPF_FUNC_skb_set_tstamp:
8209 		return &bpf_skb_set_tstamp_proto;
8210 #ifdef CONFIG_SYN_COOKIES
8211 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
8212 		return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
8213 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
8214 		return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
8215 	case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
8216 		return &bpf_tcp_raw_check_syncookie_ipv4_proto;
8217 	case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
8218 		return &bpf_tcp_raw_check_syncookie_ipv6_proto;
8219 #endif
8220 #endif
8221 	default:
8222 		return bpf_sk_base_func_proto(func_id);
8223 	}
8224 }
8225 
8226 static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8227 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8228 {
8229 	switch (func_id) {
8230 	case BPF_FUNC_perf_event_output:
8231 		return &bpf_xdp_event_output_proto;
8232 	case BPF_FUNC_get_smp_processor_id:
8233 		return &bpf_get_smp_processor_id_proto;
8234 	case BPF_FUNC_csum_diff:
8235 		return &bpf_csum_diff_proto;
8236 	case BPF_FUNC_xdp_adjust_head:
8237 		return &bpf_xdp_adjust_head_proto;
8238 	case BPF_FUNC_xdp_adjust_meta:
8239 		return &bpf_xdp_adjust_meta_proto;
8240 	case BPF_FUNC_redirect:
8241 		return &bpf_xdp_redirect_proto;
8242 	case BPF_FUNC_redirect_map:
8243 		return &bpf_xdp_redirect_map_proto;
8244 	case BPF_FUNC_xdp_adjust_tail:
8245 		return &bpf_xdp_adjust_tail_proto;
8246 	case BPF_FUNC_xdp_get_buff_len:
8247 		return &bpf_xdp_get_buff_len_proto;
8248 	case BPF_FUNC_xdp_load_bytes:
8249 		return &bpf_xdp_load_bytes_proto;
8250 	case BPF_FUNC_xdp_store_bytes:
8251 		return &bpf_xdp_store_bytes_proto;
8252 	case BPF_FUNC_fib_lookup:
8253 		return &bpf_xdp_fib_lookup_proto;
8254 	case BPF_FUNC_check_mtu:
8255 		return &bpf_xdp_check_mtu_proto;
8256 #ifdef CONFIG_INET
8257 	case BPF_FUNC_sk_lookup_udp:
8258 		return &bpf_xdp_sk_lookup_udp_proto;
8259 	case BPF_FUNC_sk_lookup_tcp:
8260 		return &bpf_xdp_sk_lookup_tcp_proto;
8261 	case BPF_FUNC_sk_release:
8262 		return &bpf_sk_release_proto;
8263 	case BPF_FUNC_skc_lookup_tcp:
8264 		return &bpf_xdp_skc_lookup_tcp_proto;
8265 	case BPF_FUNC_tcp_check_syncookie:
8266 		return &bpf_tcp_check_syncookie_proto;
8267 	case BPF_FUNC_tcp_gen_syncookie:
8268 		return &bpf_tcp_gen_syncookie_proto;
8269 #ifdef CONFIG_SYN_COOKIES
8270 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
8271 		return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
8272 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
8273 		return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
8274 	case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
8275 		return &bpf_tcp_raw_check_syncookie_ipv4_proto;
8276 	case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
8277 		return &bpf_tcp_raw_check_syncookie_ipv6_proto;
8278 #endif
8279 #endif
8280 	default:
8281 		return bpf_sk_base_func_proto(func_id);
8282 	}
8283 
8284 #if IS_MODULE(CONFIG_NF_CONNTRACK) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)
8285 	/* The nf_conn___init type is used in the NF_CONNTRACK kfuncs. The
8286 	 * kfuncs are defined in two different modules, and we want to be able
8287 	 * to use them interchangably with the same BTF type ID. Because modules
8288 	 * can't de-duplicate BTF IDs between each other, we need the type to be
8289 	 * referenced in the vmlinux BTF or the verifier will get confused about
8290 	 * the different types. So we add this dummy type reference which will
8291 	 * be included in vmlinux BTF, allowing both modules to refer to the
8292 	 * same type ID.
8293 	 */
8294 	BTF_TYPE_EMIT(struct nf_conn___init);
8295 #endif
8296 }
8297 
8298 const struct bpf_func_proto bpf_sock_map_update_proto __weak;
8299 const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
8300 
8301 static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8302 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8303 {
8304 	const struct bpf_func_proto *func_proto;
8305 
8306 	func_proto = cgroup_common_func_proto(func_id, prog);
8307 	if (func_proto)
8308 		return func_proto;
8309 
8310 	switch (func_id) {
8311 	case BPF_FUNC_setsockopt:
8312 		return &bpf_sock_ops_setsockopt_proto;
8313 	case BPF_FUNC_getsockopt:
8314 		return &bpf_sock_ops_getsockopt_proto;
8315 	case BPF_FUNC_sock_ops_cb_flags_set:
8316 		return &bpf_sock_ops_cb_flags_set_proto;
8317 	case BPF_FUNC_sock_map_update:
8318 		return &bpf_sock_map_update_proto;
8319 	case BPF_FUNC_sock_hash_update:
8320 		return &bpf_sock_hash_update_proto;
8321 	case BPF_FUNC_get_socket_cookie:
8322 		return &bpf_get_socket_cookie_sock_ops_proto;
8323 	case BPF_FUNC_perf_event_output:
8324 		return &bpf_event_output_data_proto;
8325 	case BPF_FUNC_sk_storage_get:
8326 		return &bpf_sk_storage_get_proto;
8327 	case BPF_FUNC_sk_storage_delete:
8328 		return &bpf_sk_storage_delete_proto;
8329 	case BPF_FUNC_get_netns_cookie:
8330 		return &bpf_get_netns_cookie_sock_ops_proto;
8331 #ifdef CONFIG_INET
8332 	case BPF_FUNC_load_hdr_opt:
8333 		return &bpf_sock_ops_load_hdr_opt_proto;
8334 	case BPF_FUNC_store_hdr_opt:
8335 		return &bpf_sock_ops_store_hdr_opt_proto;
8336 	case BPF_FUNC_reserve_hdr_opt:
8337 		return &bpf_sock_ops_reserve_hdr_opt_proto;
8338 	case BPF_FUNC_tcp_sock:
8339 		return &bpf_tcp_sock_proto;
8340 #endif /* CONFIG_INET */
8341 	default:
8342 		return bpf_sk_base_func_proto(func_id);
8343 	}
8344 }
8345 
8346 const struct bpf_func_proto bpf_msg_redirect_map_proto __weak;
8347 const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak;
8348 
8349 static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8350 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8351 {
8352 	switch (func_id) {
8353 	case BPF_FUNC_msg_redirect_map:
8354 		return &bpf_msg_redirect_map_proto;
8355 	case BPF_FUNC_msg_redirect_hash:
8356 		return &bpf_msg_redirect_hash_proto;
8357 	case BPF_FUNC_msg_apply_bytes:
8358 		return &bpf_msg_apply_bytes_proto;
8359 	case BPF_FUNC_msg_cork_bytes:
8360 		return &bpf_msg_cork_bytes_proto;
8361 	case BPF_FUNC_msg_pull_data:
8362 		return &bpf_msg_pull_data_proto;
8363 	case BPF_FUNC_msg_push_data:
8364 		return &bpf_msg_push_data_proto;
8365 	case BPF_FUNC_msg_pop_data:
8366 		return &bpf_msg_pop_data_proto;
8367 	case BPF_FUNC_perf_event_output:
8368 		return &bpf_event_output_data_proto;
8369 	case BPF_FUNC_get_current_uid_gid:
8370 		return &bpf_get_current_uid_gid_proto;
8371 	case BPF_FUNC_get_current_pid_tgid:
8372 		return &bpf_get_current_pid_tgid_proto;
8373 	case BPF_FUNC_sk_storage_get:
8374 		return &bpf_sk_storage_get_proto;
8375 	case BPF_FUNC_sk_storage_delete:
8376 		return &bpf_sk_storage_delete_proto;
8377 	case BPF_FUNC_get_netns_cookie:
8378 		return &bpf_get_netns_cookie_sk_msg_proto;
8379 #ifdef CONFIG_CGROUP_NET_CLASSID
8380 	case BPF_FUNC_get_cgroup_classid:
8381 		return &bpf_get_cgroup_classid_curr_proto;
8382 #endif
8383 	default:
8384 		return bpf_sk_base_func_proto(func_id);
8385 	}
8386 }
8387 
8388 const struct bpf_func_proto bpf_sk_redirect_map_proto __weak;
8389 const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak;
8390 
8391 static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8392 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8393 {
8394 	switch (func_id) {
8395 	case BPF_FUNC_skb_store_bytes:
8396 		return &bpf_skb_store_bytes_proto;
8397 	case BPF_FUNC_skb_load_bytes:
8398 		return &bpf_skb_load_bytes_proto;
8399 	case BPF_FUNC_skb_pull_data:
8400 		return &sk_skb_pull_data_proto;
8401 	case BPF_FUNC_skb_change_tail:
8402 		return &sk_skb_change_tail_proto;
8403 	case BPF_FUNC_skb_change_head:
8404 		return &sk_skb_change_head_proto;
8405 	case BPF_FUNC_skb_adjust_room:
8406 		return &sk_skb_adjust_room_proto;
8407 	case BPF_FUNC_get_socket_cookie:
8408 		return &bpf_get_socket_cookie_proto;
8409 	case BPF_FUNC_get_socket_uid:
8410 		return &bpf_get_socket_uid_proto;
8411 	case BPF_FUNC_sk_redirect_map:
8412 		return &bpf_sk_redirect_map_proto;
8413 	case BPF_FUNC_sk_redirect_hash:
8414 		return &bpf_sk_redirect_hash_proto;
8415 	case BPF_FUNC_perf_event_output:
8416 		return &bpf_skb_event_output_proto;
8417 #ifdef CONFIG_INET
8418 	case BPF_FUNC_sk_lookup_tcp:
8419 		return &bpf_sk_lookup_tcp_proto;
8420 	case BPF_FUNC_sk_lookup_udp:
8421 		return &bpf_sk_lookup_udp_proto;
8422 	case BPF_FUNC_sk_release:
8423 		return &bpf_sk_release_proto;
8424 	case BPF_FUNC_skc_lookup_tcp:
8425 		return &bpf_skc_lookup_tcp_proto;
8426 #endif
8427 	default:
8428 		return bpf_sk_base_func_proto(func_id);
8429 	}
8430 }
8431 
8432 static const struct bpf_func_proto *
flow_dissector_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8433 flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8434 {
8435 	switch (func_id) {
8436 	case BPF_FUNC_skb_load_bytes:
8437 		return &bpf_flow_dissector_load_bytes_proto;
8438 	default:
8439 		return bpf_sk_base_func_proto(func_id);
8440 	}
8441 }
8442 
8443 static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8444 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8445 {
8446 	switch (func_id) {
8447 	case BPF_FUNC_skb_load_bytes:
8448 		return &bpf_skb_load_bytes_proto;
8449 	case BPF_FUNC_skb_pull_data:
8450 		return &bpf_skb_pull_data_proto;
8451 	case BPF_FUNC_csum_diff:
8452 		return &bpf_csum_diff_proto;
8453 	case BPF_FUNC_get_cgroup_classid:
8454 		return &bpf_get_cgroup_classid_proto;
8455 	case BPF_FUNC_get_route_realm:
8456 		return &bpf_get_route_realm_proto;
8457 	case BPF_FUNC_get_hash_recalc:
8458 		return &bpf_get_hash_recalc_proto;
8459 	case BPF_FUNC_perf_event_output:
8460 		return &bpf_skb_event_output_proto;
8461 	case BPF_FUNC_get_smp_processor_id:
8462 		return &bpf_get_smp_processor_id_proto;
8463 	case BPF_FUNC_skb_under_cgroup:
8464 		return &bpf_skb_under_cgroup_proto;
8465 	default:
8466 		return bpf_sk_base_func_proto(func_id);
8467 	}
8468 }
8469 
8470 static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8471 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8472 {
8473 	switch (func_id) {
8474 	case BPF_FUNC_lwt_push_encap:
8475 		return &bpf_lwt_in_push_encap_proto;
8476 	default:
8477 		return lwt_out_func_proto(func_id, prog);
8478 	}
8479 }
8480 
8481 static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8482 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8483 {
8484 	switch (func_id) {
8485 	case BPF_FUNC_skb_get_tunnel_key:
8486 		return &bpf_skb_get_tunnel_key_proto;
8487 	case BPF_FUNC_skb_set_tunnel_key:
8488 		return bpf_get_skb_set_tunnel_proto(func_id);
8489 	case BPF_FUNC_skb_get_tunnel_opt:
8490 		return &bpf_skb_get_tunnel_opt_proto;
8491 	case BPF_FUNC_skb_set_tunnel_opt:
8492 		return bpf_get_skb_set_tunnel_proto(func_id);
8493 	case BPF_FUNC_redirect:
8494 		return &bpf_redirect_proto;
8495 	case BPF_FUNC_clone_redirect:
8496 		return &bpf_clone_redirect_proto;
8497 	case BPF_FUNC_skb_change_tail:
8498 		return &bpf_skb_change_tail_proto;
8499 	case BPF_FUNC_skb_change_head:
8500 		return &bpf_skb_change_head_proto;
8501 	case BPF_FUNC_skb_store_bytes:
8502 		return &bpf_skb_store_bytes_proto;
8503 	case BPF_FUNC_csum_update:
8504 		return &bpf_csum_update_proto;
8505 	case BPF_FUNC_csum_level:
8506 		return &bpf_csum_level_proto;
8507 	case BPF_FUNC_l3_csum_replace:
8508 		return &bpf_l3_csum_replace_proto;
8509 	case BPF_FUNC_l4_csum_replace:
8510 		return &bpf_l4_csum_replace_proto;
8511 	case BPF_FUNC_set_hash_invalid:
8512 		return &bpf_set_hash_invalid_proto;
8513 	case BPF_FUNC_lwt_push_encap:
8514 		return &bpf_lwt_xmit_push_encap_proto;
8515 	default:
8516 		return lwt_out_func_proto(func_id, prog);
8517 	}
8518 }
8519 
8520 static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8521 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8522 {
8523 	switch (func_id) {
8524 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
8525 	case BPF_FUNC_lwt_seg6_store_bytes:
8526 		return &bpf_lwt_seg6_store_bytes_proto;
8527 	case BPF_FUNC_lwt_seg6_action:
8528 		return &bpf_lwt_seg6_action_proto;
8529 	case BPF_FUNC_lwt_seg6_adjust_srh:
8530 		return &bpf_lwt_seg6_adjust_srh_proto;
8531 #endif
8532 	default:
8533 		return lwt_out_func_proto(func_id, prog);
8534 	}
8535 }
8536 
bpf_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8537 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
8538 				    const struct bpf_prog *prog,
8539 				    struct bpf_insn_access_aux *info)
8540 {
8541 	const int size_default = sizeof(__u32);
8542 
8543 	if (off < 0 || off >= sizeof(struct __sk_buff))
8544 		return false;
8545 
8546 	/* The verifier guarantees that size > 0. */
8547 	if (off % size != 0)
8548 		return false;
8549 
8550 	switch (off) {
8551 	case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8552 		if (off + size > offsetofend(struct __sk_buff, cb[4]))
8553 			return false;
8554 		break;
8555 	case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
8556 	case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
8557 	case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
8558 	case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
8559 	case bpf_ctx_range(struct __sk_buff, data):
8560 	case bpf_ctx_range(struct __sk_buff, data_meta):
8561 	case bpf_ctx_range(struct __sk_buff, data_end):
8562 		if (size != size_default)
8563 			return false;
8564 		break;
8565 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
8566 		return false;
8567 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8568 		if (type == BPF_WRITE || size != sizeof(__u64))
8569 			return false;
8570 		break;
8571 	case bpf_ctx_range(struct __sk_buff, tstamp):
8572 		if (size != sizeof(__u64))
8573 			return false;
8574 		break;
8575 	case offsetof(struct __sk_buff, sk):
8576 		if (type == BPF_WRITE || size != sizeof(__u64))
8577 			return false;
8578 		info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
8579 		break;
8580 	case offsetof(struct __sk_buff, tstamp_type):
8581 		return false;
8582 	case offsetofend(struct __sk_buff, tstamp_type) ... offsetof(struct __sk_buff, hwtstamp) - 1:
8583 		/* Explicitly prohibit access to padding in __sk_buff. */
8584 		return false;
8585 	default:
8586 		/* Only narrow read access allowed for now. */
8587 		if (type == BPF_WRITE) {
8588 			if (size != size_default)
8589 				return false;
8590 		} else {
8591 			bpf_ctx_record_field_size(info, size_default);
8592 			if (!bpf_ctx_narrow_access_ok(off, size, size_default))
8593 				return false;
8594 		}
8595 	}
8596 
8597 	return true;
8598 }
8599 
sk_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8600 static bool sk_filter_is_valid_access(int off, int size,
8601 				      enum bpf_access_type type,
8602 				      const struct bpf_prog *prog,
8603 				      struct bpf_insn_access_aux *info)
8604 {
8605 	switch (off) {
8606 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8607 	case bpf_ctx_range(struct __sk_buff, data):
8608 	case bpf_ctx_range(struct __sk_buff, data_meta):
8609 	case bpf_ctx_range(struct __sk_buff, data_end):
8610 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8611 	case bpf_ctx_range(struct __sk_buff, tstamp):
8612 	case bpf_ctx_range(struct __sk_buff, wire_len):
8613 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8614 		return false;
8615 	}
8616 
8617 	if (type == BPF_WRITE) {
8618 		switch (off) {
8619 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8620 			break;
8621 		default:
8622 			return false;
8623 		}
8624 	}
8625 
8626 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8627 }
8628 
cg_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8629 static bool cg_skb_is_valid_access(int off, int size,
8630 				   enum bpf_access_type type,
8631 				   const struct bpf_prog *prog,
8632 				   struct bpf_insn_access_aux *info)
8633 {
8634 	switch (off) {
8635 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8636 	case bpf_ctx_range(struct __sk_buff, data_meta):
8637 	case bpf_ctx_range(struct __sk_buff, wire_len):
8638 		return false;
8639 	case bpf_ctx_range(struct __sk_buff, data):
8640 	case bpf_ctx_range(struct __sk_buff, data_end):
8641 		if (!bpf_capable())
8642 			return false;
8643 		break;
8644 	}
8645 
8646 	if (type == BPF_WRITE) {
8647 		switch (off) {
8648 		case bpf_ctx_range(struct __sk_buff, mark):
8649 		case bpf_ctx_range(struct __sk_buff, priority):
8650 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8651 			break;
8652 		case bpf_ctx_range(struct __sk_buff, tstamp):
8653 			if (!bpf_capable())
8654 				return false;
8655 			break;
8656 		default:
8657 			return false;
8658 		}
8659 	}
8660 
8661 	switch (off) {
8662 	case bpf_ctx_range(struct __sk_buff, data):
8663 		info->reg_type = PTR_TO_PACKET;
8664 		break;
8665 	case bpf_ctx_range(struct __sk_buff, data_end):
8666 		info->reg_type = PTR_TO_PACKET_END;
8667 		break;
8668 	}
8669 
8670 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8671 }
8672 
lwt_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8673 static bool lwt_is_valid_access(int off, int size,
8674 				enum bpf_access_type type,
8675 				const struct bpf_prog *prog,
8676 				struct bpf_insn_access_aux *info)
8677 {
8678 	switch (off) {
8679 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8680 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8681 	case bpf_ctx_range(struct __sk_buff, data_meta):
8682 	case bpf_ctx_range(struct __sk_buff, tstamp):
8683 	case bpf_ctx_range(struct __sk_buff, wire_len):
8684 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8685 		return false;
8686 	}
8687 
8688 	if (type == BPF_WRITE) {
8689 		switch (off) {
8690 		case bpf_ctx_range(struct __sk_buff, mark):
8691 		case bpf_ctx_range(struct __sk_buff, priority):
8692 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8693 			break;
8694 		default:
8695 			return false;
8696 		}
8697 	}
8698 
8699 	switch (off) {
8700 	case bpf_ctx_range(struct __sk_buff, data):
8701 		info->reg_type = PTR_TO_PACKET;
8702 		break;
8703 	case bpf_ctx_range(struct __sk_buff, data_end):
8704 		info->reg_type = PTR_TO_PACKET_END;
8705 		break;
8706 	}
8707 
8708 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8709 }
8710 
8711 /* Attach type specific accesses */
__sock_filter_check_attach_type(int off,enum bpf_access_type access_type,enum bpf_attach_type attach_type)8712 static bool __sock_filter_check_attach_type(int off,
8713 					    enum bpf_access_type access_type,
8714 					    enum bpf_attach_type attach_type)
8715 {
8716 	switch (off) {
8717 	case offsetof(struct bpf_sock, bound_dev_if):
8718 	case offsetof(struct bpf_sock, mark):
8719 	case offsetof(struct bpf_sock, priority):
8720 		switch (attach_type) {
8721 		case BPF_CGROUP_INET_SOCK_CREATE:
8722 		case BPF_CGROUP_INET_SOCK_RELEASE:
8723 			goto full_access;
8724 		default:
8725 			return false;
8726 		}
8727 	case bpf_ctx_range(struct bpf_sock, src_ip4):
8728 		switch (attach_type) {
8729 		case BPF_CGROUP_INET4_POST_BIND:
8730 			goto read_only;
8731 		default:
8732 			return false;
8733 		}
8734 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8735 		switch (attach_type) {
8736 		case BPF_CGROUP_INET6_POST_BIND:
8737 			goto read_only;
8738 		default:
8739 			return false;
8740 		}
8741 	case bpf_ctx_range(struct bpf_sock, src_port):
8742 		switch (attach_type) {
8743 		case BPF_CGROUP_INET4_POST_BIND:
8744 		case BPF_CGROUP_INET6_POST_BIND:
8745 			goto read_only;
8746 		default:
8747 			return false;
8748 		}
8749 	}
8750 read_only:
8751 	return access_type == BPF_READ;
8752 full_access:
8753 	return true;
8754 }
8755 
bpf_sock_common_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8756 bool bpf_sock_common_is_valid_access(int off, int size,
8757 				     enum bpf_access_type type,
8758 				     struct bpf_insn_access_aux *info)
8759 {
8760 	switch (off) {
8761 	case bpf_ctx_range_till(struct bpf_sock, type, priority):
8762 		return false;
8763 	default:
8764 		return bpf_sock_is_valid_access(off, size, type, info);
8765 	}
8766 }
8767 
bpf_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8768 bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
8769 			      struct bpf_insn_access_aux *info)
8770 {
8771 	const int size_default = sizeof(__u32);
8772 	int field_size;
8773 
8774 	if (off < 0 || off >= sizeof(struct bpf_sock))
8775 		return false;
8776 	if (off % size != 0)
8777 		return false;
8778 
8779 	switch (off) {
8780 	case offsetof(struct bpf_sock, state):
8781 	case offsetof(struct bpf_sock, family):
8782 	case offsetof(struct bpf_sock, type):
8783 	case offsetof(struct bpf_sock, protocol):
8784 	case offsetof(struct bpf_sock, src_port):
8785 	case offsetof(struct bpf_sock, rx_queue_mapping):
8786 	case bpf_ctx_range(struct bpf_sock, src_ip4):
8787 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8788 	case bpf_ctx_range(struct bpf_sock, dst_ip4):
8789 	case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
8790 		bpf_ctx_record_field_size(info, size_default);
8791 		return bpf_ctx_narrow_access_ok(off, size, size_default);
8792 	case bpf_ctx_range(struct bpf_sock, dst_port):
8793 		field_size = size == size_default ?
8794 			size_default : sizeof_field(struct bpf_sock, dst_port);
8795 		bpf_ctx_record_field_size(info, field_size);
8796 		return bpf_ctx_narrow_access_ok(off, size, field_size);
8797 	case offsetofend(struct bpf_sock, dst_port) ...
8798 	     offsetof(struct bpf_sock, dst_ip4) - 1:
8799 		return false;
8800 	}
8801 
8802 	return size == size_default;
8803 }
8804 
sock_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8805 static bool sock_filter_is_valid_access(int off, int size,
8806 					enum bpf_access_type type,
8807 					const struct bpf_prog *prog,
8808 					struct bpf_insn_access_aux *info)
8809 {
8810 	if (!bpf_sock_is_valid_access(off, size, type, info))
8811 		return false;
8812 	return __sock_filter_check_attach_type(off, type,
8813 					       prog->expected_attach_type);
8814 }
8815 
bpf_noop_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8816 static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write,
8817 			     const struct bpf_prog *prog)
8818 {
8819 	/* Neither direct read nor direct write requires any preliminary
8820 	 * action.
8821 	 */
8822 	return 0;
8823 }
8824 
bpf_unclone_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog,int drop_verdict)8825 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
8826 				const struct bpf_prog *prog, int drop_verdict)
8827 {
8828 	struct bpf_insn *insn = insn_buf;
8829 
8830 	if (!direct_write)
8831 		return 0;
8832 
8833 	/* if (!skb->cloned)
8834 	 *       goto start;
8835 	 *
8836 	 * (Fast-path, otherwise approximation that we might be
8837 	 *  a clone, do the rest in helper.)
8838 	 */
8839 	*insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET);
8840 	*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
8841 	*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
8842 
8843 	/* ret = bpf_skb_pull_data(skb, 0); */
8844 	*insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
8845 	*insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
8846 	*insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
8847 			       BPF_FUNC_skb_pull_data);
8848 	/* if (!ret)
8849 	 *      goto restore;
8850 	 * return TC_ACT_SHOT;
8851 	 */
8852 	*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
8853 	*insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
8854 	*insn++ = BPF_EXIT_INSN();
8855 
8856 	/* restore: */
8857 	*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
8858 	/* start: */
8859 	*insn++ = prog->insnsi[0];
8860 
8861 	return insn - insn_buf;
8862 }
8863 
bpf_gen_ld_abs(const struct bpf_insn * orig,struct bpf_insn * insn_buf)8864 static int bpf_gen_ld_abs(const struct bpf_insn *orig,
8865 			  struct bpf_insn *insn_buf)
8866 {
8867 	bool indirect = BPF_MODE(orig->code) == BPF_IND;
8868 	struct bpf_insn *insn = insn_buf;
8869 
8870 	if (!indirect) {
8871 		*insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
8872 	} else {
8873 		*insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
8874 		if (orig->imm)
8875 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
8876 	}
8877 	/* We're guaranteed here that CTX is in R6. */
8878 	*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);
8879 
8880 	switch (BPF_SIZE(orig->code)) {
8881 	case BPF_B:
8882 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
8883 		break;
8884 	case BPF_H:
8885 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
8886 		break;
8887 	case BPF_W:
8888 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
8889 		break;
8890 	}
8891 
8892 	*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
8893 	*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
8894 	*insn++ = BPF_EXIT_INSN();
8895 
8896 	return insn - insn_buf;
8897 }
8898 
tc_cls_act_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8899 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
8900 			       const struct bpf_prog *prog)
8901 {
8902 	return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
8903 }
8904 
tc_cls_act_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8905 static bool tc_cls_act_is_valid_access(int off, int size,
8906 				       enum bpf_access_type type,
8907 				       const struct bpf_prog *prog,
8908 				       struct bpf_insn_access_aux *info)
8909 {
8910 	if (type == BPF_WRITE) {
8911 		switch (off) {
8912 		case bpf_ctx_range(struct __sk_buff, mark):
8913 		case bpf_ctx_range(struct __sk_buff, tc_index):
8914 		case bpf_ctx_range(struct __sk_buff, priority):
8915 		case bpf_ctx_range(struct __sk_buff, tc_classid):
8916 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8917 		case bpf_ctx_range(struct __sk_buff, tstamp):
8918 		case bpf_ctx_range(struct __sk_buff, queue_mapping):
8919 			break;
8920 		default:
8921 			return false;
8922 		}
8923 	}
8924 
8925 	switch (off) {
8926 	case bpf_ctx_range(struct __sk_buff, data):
8927 		info->reg_type = PTR_TO_PACKET;
8928 		break;
8929 	case bpf_ctx_range(struct __sk_buff, data_meta):
8930 		info->reg_type = PTR_TO_PACKET_META;
8931 		break;
8932 	case bpf_ctx_range(struct __sk_buff, data_end):
8933 		info->reg_type = PTR_TO_PACKET_END;
8934 		break;
8935 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8936 		return false;
8937 	case offsetof(struct __sk_buff, tstamp_type):
8938 		/* The convert_ctx_access() on reading and writing
8939 		 * __sk_buff->tstamp depends on whether the bpf prog
8940 		 * has used __sk_buff->tstamp_type or not.
8941 		 * Thus, we need to set prog->tstamp_type_access
8942 		 * earlier during is_valid_access() here.
8943 		 */
8944 		((struct bpf_prog *)prog)->tstamp_type_access = 1;
8945 		return size == sizeof(__u8);
8946 	}
8947 
8948 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8949 }
8950 
8951 DEFINE_MUTEX(nf_conn_btf_access_lock);
8952 EXPORT_SYMBOL_GPL(nf_conn_btf_access_lock);
8953 
8954 int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
8955 			      const struct bpf_reg_state *reg,
8956 			      int off, int size);
8957 EXPORT_SYMBOL_GPL(nfct_btf_struct_access);
8958 
tc_cls_act_btf_struct_access(struct bpf_verifier_log * log,const struct bpf_reg_state * reg,int off,int size)8959 static int tc_cls_act_btf_struct_access(struct bpf_verifier_log *log,
8960 					const struct bpf_reg_state *reg,
8961 					int off, int size)
8962 {
8963 	int ret = -EACCES;
8964 
8965 	mutex_lock(&nf_conn_btf_access_lock);
8966 	if (nfct_btf_struct_access)
8967 		ret = nfct_btf_struct_access(log, reg, off, size);
8968 	mutex_unlock(&nf_conn_btf_access_lock);
8969 
8970 	return ret;
8971 }
8972 
__is_valid_xdp_access(int off,int size)8973 static bool __is_valid_xdp_access(int off, int size)
8974 {
8975 	if (off < 0 || off >= sizeof(struct xdp_md))
8976 		return false;
8977 	if (off % size != 0)
8978 		return false;
8979 	if (size != sizeof(__u32))
8980 		return false;
8981 
8982 	return true;
8983 }
8984 
xdp_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8985 static bool xdp_is_valid_access(int off, int size,
8986 				enum bpf_access_type type,
8987 				const struct bpf_prog *prog,
8988 				struct bpf_insn_access_aux *info)
8989 {
8990 	if (prog->expected_attach_type != BPF_XDP_DEVMAP) {
8991 		switch (off) {
8992 		case offsetof(struct xdp_md, egress_ifindex):
8993 			return false;
8994 		}
8995 	}
8996 
8997 	if (type == BPF_WRITE) {
8998 		if (bpf_prog_is_offloaded(prog->aux)) {
8999 			switch (off) {
9000 			case offsetof(struct xdp_md, rx_queue_index):
9001 				return __is_valid_xdp_access(off, size);
9002 			}
9003 		}
9004 		return false;
9005 	}
9006 
9007 	switch (off) {
9008 	case offsetof(struct xdp_md, data):
9009 		info->reg_type = PTR_TO_PACKET;
9010 		break;
9011 	case offsetof(struct xdp_md, data_meta):
9012 		info->reg_type = PTR_TO_PACKET_META;
9013 		break;
9014 	case offsetof(struct xdp_md, data_end):
9015 		info->reg_type = PTR_TO_PACKET_END;
9016 		break;
9017 	}
9018 
9019 	return __is_valid_xdp_access(off, size);
9020 }
9021 
bpf_warn_invalid_xdp_action(struct net_device * dev,struct bpf_prog * prog,u32 act)9022 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)
9023 {
9024 	const u32 act_max = XDP_REDIRECT;
9025 
9026 	pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
9027 		     act > act_max ? "Illegal" : "Driver unsupported",
9028 		     act, prog->aux->name, prog->aux->id, dev ? dev->name : "N/A");
9029 }
9030 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
9031 
xdp_btf_struct_access(struct bpf_verifier_log * log,const struct bpf_reg_state * reg,int off,int size)9032 static int xdp_btf_struct_access(struct bpf_verifier_log *log,
9033 				 const struct bpf_reg_state *reg,
9034 				 int off, int size)
9035 {
9036 	int ret = -EACCES;
9037 
9038 	mutex_lock(&nf_conn_btf_access_lock);
9039 	if (nfct_btf_struct_access)
9040 		ret = nfct_btf_struct_access(log, reg, off, size);
9041 	mutex_unlock(&nf_conn_btf_access_lock);
9042 
9043 	return ret;
9044 }
9045 
sock_addr_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)9046 static bool sock_addr_is_valid_access(int off, int size,
9047 				      enum bpf_access_type type,
9048 				      const struct bpf_prog *prog,
9049 				      struct bpf_insn_access_aux *info)
9050 {
9051 	const int size_default = sizeof(__u32);
9052 
9053 	if (off < 0 || off >= sizeof(struct bpf_sock_addr))
9054 		return false;
9055 	if (off % size != 0)
9056 		return false;
9057 
9058 	/* Disallow access to IPv6 fields from IPv4 contex and vise
9059 	 * versa.
9060 	 */
9061 	switch (off) {
9062 	case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
9063 		switch (prog->expected_attach_type) {
9064 		case BPF_CGROUP_INET4_BIND:
9065 		case BPF_CGROUP_INET4_CONNECT:
9066 		case BPF_CGROUP_INET4_GETPEERNAME:
9067 		case BPF_CGROUP_INET4_GETSOCKNAME:
9068 		case BPF_CGROUP_UDP4_SENDMSG:
9069 		case BPF_CGROUP_UDP4_RECVMSG:
9070 			break;
9071 		default:
9072 			return false;
9073 		}
9074 		break;
9075 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
9076 		switch (prog->expected_attach_type) {
9077 		case BPF_CGROUP_INET6_BIND:
9078 		case BPF_CGROUP_INET6_CONNECT:
9079 		case BPF_CGROUP_INET6_GETPEERNAME:
9080 		case BPF_CGROUP_INET6_GETSOCKNAME:
9081 		case BPF_CGROUP_UDP6_SENDMSG:
9082 		case BPF_CGROUP_UDP6_RECVMSG:
9083 			break;
9084 		default:
9085 			return false;
9086 		}
9087 		break;
9088 	case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
9089 		switch (prog->expected_attach_type) {
9090 		case BPF_CGROUP_UDP4_SENDMSG:
9091 			break;
9092 		default:
9093 			return false;
9094 		}
9095 		break;
9096 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
9097 				msg_src_ip6[3]):
9098 		switch (prog->expected_attach_type) {
9099 		case BPF_CGROUP_UDP6_SENDMSG:
9100 			break;
9101 		default:
9102 			return false;
9103 		}
9104 		break;
9105 	}
9106 
9107 	switch (off) {
9108 	case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
9109 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
9110 	case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
9111 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
9112 				msg_src_ip6[3]):
9113 	case bpf_ctx_range(struct bpf_sock_addr, user_port):
9114 		if (type == BPF_READ) {
9115 			bpf_ctx_record_field_size(info, size_default);
9116 
9117 			if (bpf_ctx_wide_access_ok(off, size,
9118 						   struct bpf_sock_addr,
9119 						   user_ip6))
9120 				return true;
9121 
9122 			if (bpf_ctx_wide_access_ok(off, size,
9123 						   struct bpf_sock_addr,
9124 						   msg_src_ip6))
9125 				return true;
9126 
9127 			if (!bpf_ctx_narrow_access_ok(off, size, size_default))
9128 				return false;
9129 		} else {
9130 			if (bpf_ctx_wide_access_ok(off, size,
9131 						   struct bpf_sock_addr,
9132 						   user_ip6))
9133 				return true;
9134 
9135 			if (bpf_ctx_wide_access_ok(off, size,
9136 						   struct bpf_sock_addr,
9137 						   msg_src_ip6))
9138 				return true;
9139 
9140 			if (size != size_default)
9141 				return false;
9142 		}
9143 		break;
9144 	case offsetof(struct bpf_sock_addr, sk):
9145 		if (type != BPF_READ)
9146 			return false;
9147 		if (size != sizeof(__u64))
9148 			return false;
9149 		info->reg_type = PTR_TO_SOCKET;
9150 		break;
9151 	default:
9152 		if (type == BPF_READ) {
9153 			if (size != size_default)
9154 				return false;
9155 		} else {
9156 			return false;
9157 		}
9158 	}
9159 
9160 	return true;
9161 }
9162 
sock_ops_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)9163 static bool sock_ops_is_valid_access(int off, int size,
9164 				     enum bpf_access_type type,
9165 				     const struct bpf_prog *prog,
9166 				     struct bpf_insn_access_aux *info)
9167 {
9168 	const int size_default = sizeof(__u32);
9169 
9170 	if (off < 0 || off >= sizeof(struct bpf_sock_ops))
9171 		return false;
9172 
9173 	/* The verifier guarantees that size > 0. */
9174 	if (off % size != 0)
9175 		return false;
9176 
9177 	if (type == BPF_WRITE) {
9178 		switch (off) {
9179 		case offsetof(struct bpf_sock_ops, reply):
9180 		case offsetof(struct bpf_sock_ops, sk_txhash):
9181 			if (size != size_default)
9182 				return false;
9183 			break;
9184 		default:
9185 			return false;
9186 		}
9187 	} else {
9188 		switch (off) {
9189 		case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
9190 					bytes_acked):
9191 			if (size != sizeof(__u64))
9192 				return false;
9193 			break;
9194 		case offsetof(struct bpf_sock_ops, sk):
9195 			if (size != sizeof(__u64))
9196 				return false;
9197 			info->reg_type = PTR_TO_SOCKET_OR_NULL;
9198 			break;
9199 		case offsetof(struct bpf_sock_ops, skb_data):
9200 			if (size != sizeof(__u64))
9201 				return false;
9202 			info->reg_type = PTR_TO_PACKET;
9203 			break;
9204 		case offsetof(struct bpf_sock_ops, skb_data_end):
9205 			if (size != sizeof(__u64))
9206 				return false;
9207 			info->reg_type = PTR_TO_PACKET_END;
9208 			break;
9209 		case offsetof(struct bpf_sock_ops, skb_tcp_flags):
9210 			bpf_ctx_record_field_size(info, size_default);
9211 			return bpf_ctx_narrow_access_ok(off, size,
9212 							size_default);
9213 		case offsetof(struct bpf_sock_ops, skb_hwtstamp):
9214 			if (size != sizeof(__u64))
9215 				return false;
9216 			break;
9217 		default:
9218 			if (size != size_default)
9219 				return false;
9220 			break;
9221 		}
9222 	}
9223 
9224 	return true;
9225 }
9226 
sk_skb_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)9227 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
9228 			   const struct bpf_prog *prog)
9229 {
9230 	return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
9231 }
9232 
sk_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)9233 static bool sk_skb_is_valid_access(int off, int size,
9234 				   enum bpf_access_type type,
9235 				   const struct bpf_prog *prog,
9236 				   struct bpf_insn_access_aux *info)
9237 {
9238 	switch (off) {
9239 	case bpf_ctx_range(struct __sk_buff, tc_classid):
9240 	case bpf_ctx_range(struct __sk_buff, data_meta):
9241 	case bpf_ctx_range(struct __sk_buff, tstamp):
9242 	case bpf_ctx_range(struct __sk_buff, wire_len):
9243 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
9244 		return false;
9245 	}
9246 
9247 	if (type == BPF_WRITE) {
9248 		switch (off) {
9249 		case bpf_ctx_range(struct __sk_buff, tc_index):
9250 		case bpf_ctx_range(struct __sk_buff, priority):
9251 			break;
9252 		default:
9253 			return false;
9254 		}
9255 	}
9256 
9257 	switch (off) {
9258 	case bpf_ctx_range(struct __sk_buff, mark):
9259 		return false;
9260 	case bpf_ctx_range(struct __sk_buff, data):
9261 		info->reg_type = PTR_TO_PACKET;
9262 		break;
9263 	case bpf_ctx_range(struct __sk_buff, data_end):
9264 		info->reg_type = PTR_TO_PACKET_END;
9265 		break;
9266 	}
9267 
9268 	return bpf_skb_is_valid_access(off, size, type, prog, info);
9269 }
9270 
sk_msg_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)9271 static bool sk_msg_is_valid_access(int off, int size,
9272 				   enum bpf_access_type type,
9273 				   const struct bpf_prog *prog,
9274 				   struct bpf_insn_access_aux *info)
9275 {
9276 	if (type == BPF_WRITE)
9277 		return false;
9278 
9279 	if (off % size != 0)
9280 		return false;
9281 
9282 	switch (off) {
9283 	case offsetof(struct sk_msg_md, data):
9284 		info->reg_type = PTR_TO_PACKET;
9285 		if (size != sizeof(__u64))
9286 			return false;
9287 		break;
9288 	case offsetof(struct sk_msg_md, data_end):
9289 		info->reg_type = PTR_TO_PACKET_END;
9290 		if (size != sizeof(__u64))
9291 			return false;
9292 		break;
9293 	case offsetof(struct sk_msg_md, sk):
9294 		if (size != sizeof(__u64))
9295 			return false;
9296 		info->reg_type = PTR_TO_SOCKET;
9297 		break;
9298 	case bpf_ctx_range(struct sk_msg_md, family):
9299 	case bpf_ctx_range(struct sk_msg_md, remote_ip4):
9300 	case bpf_ctx_range(struct sk_msg_md, local_ip4):
9301 	case bpf_ctx_range_till(struct sk_msg_md, remote_ip6[0], remote_ip6[3]):
9302 	case bpf_ctx_range_till(struct sk_msg_md, local_ip6[0], local_ip6[3]):
9303 	case bpf_ctx_range(struct sk_msg_md, remote_port):
9304 	case bpf_ctx_range(struct sk_msg_md, local_port):
9305 	case bpf_ctx_range(struct sk_msg_md, size):
9306 		if (size != sizeof(__u32))
9307 			return false;
9308 		break;
9309 	default:
9310 		return false;
9311 	}
9312 	return true;
9313 }
9314 
flow_dissector_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)9315 static bool flow_dissector_is_valid_access(int off, int size,
9316 					   enum bpf_access_type type,
9317 					   const struct bpf_prog *prog,
9318 					   struct bpf_insn_access_aux *info)
9319 {
9320 	const int size_default = sizeof(__u32);
9321 
9322 	if (off < 0 || off >= sizeof(struct __sk_buff))
9323 		return false;
9324 
9325 	if (type == BPF_WRITE)
9326 		return false;
9327 
9328 	switch (off) {
9329 	case bpf_ctx_range(struct __sk_buff, data):
9330 		if (size != size_default)
9331 			return false;
9332 		info->reg_type = PTR_TO_PACKET;
9333 		return true;
9334 	case bpf_ctx_range(struct __sk_buff, data_end):
9335 		if (size != size_default)
9336 			return false;
9337 		info->reg_type = PTR_TO_PACKET_END;
9338 		return true;
9339 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
9340 		if (size != sizeof(__u64))
9341 			return false;
9342 		info->reg_type = PTR_TO_FLOW_KEYS;
9343 		return true;
9344 	default:
9345 		return false;
9346 	}
9347 }
9348 
flow_dissector_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9349 static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type,
9350 					     const struct bpf_insn *si,
9351 					     struct bpf_insn *insn_buf,
9352 					     struct bpf_prog *prog,
9353 					     u32 *target_size)
9354 
9355 {
9356 	struct bpf_insn *insn = insn_buf;
9357 
9358 	switch (si->off) {
9359 	case offsetof(struct __sk_buff, data):
9360 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data),
9361 				      si->dst_reg, si->src_reg,
9362 				      offsetof(struct bpf_flow_dissector, data));
9363 		break;
9364 
9365 	case offsetof(struct __sk_buff, data_end):
9366 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data_end),
9367 				      si->dst_reg, si->src_reg,
9368 				      offsetof(struct bpf_flow_dissector, data_end));
9369 		break;
9370 
9371 	case offsetof(struct __sk_buff, flow_keys):
9372 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, flow_keys),
9373 				      si->dst_reg, si->src_reg,
9374 				      offsetof(struct bpf_flow_dissector, flow_keys));
9375 		break;
9376 	}
9377 
9378 	return insn - insn_buf;
9379 }
9380 
bpf_convert_tstamp_type_read(const struct bpf_insn * si,struct bpf_insn * insn)9381 static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si,
9382 						     struct bpf_insn *insn)
9383 {
9384 	__u8 value_reg = si->dst_reg;
9385 	__u8 skb_reg = si->src_reg;
9386 	/* AX is needed because src_reg and dst_reg could be the same */
9387 	__u8 tmp_reg = BPF_REG_AX;
9388 
9389 	*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg,
9390 			      SKB_BF_MONO_TC_OFFSET);
9391 	*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg,
9392 				SKB_MONO_DELIVERY_TIME_MASK, 2);
9393 	*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_UNSPEC);
9394 	*insn++ = BPF_JMP_A(1);
9395 	*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_DELIVERY_MONO);
9396 
9397 	return insn;
9398 }
9399 
bpf_convert_shinfo_access(__u8 dst_reg,__u8 skb_reg,struct bpf_insn * insn)9400 static struct bpf_insn *bpf_convert_shinfo_access(__u8 dst_reg, __u8 skb_reg,
9401 						  struct bpf_insn *insn)
9402 {
9403 	/* si->dst_reg = skb_shinfo(SKB); */
9404 #ifdef NET_SKBUFF_DATA_USES_OFFSET
9405 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
9406 			      BPF_REG_AX, skb_reg,
9407 			      offsetof(struct sk_buff, end));
9408 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, head),
9409 			      dst_reg, skb_reg,
9410 			      offsetof(struct sk_buff, head));
9411 	*insn++ = BPF_ALU64_REG(BPF_ADD, dst_reg, BPF_REG_AX);
9412 #else
9413 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
9414 			      dst_reg, skb_reg,
9415 			      offsetof(struct sk_buff, end));
9416 #endif
9417 
9418 	return insn;
9419 }
9420 
bpf_convert_tstamp_read(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)9421 static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog,
9422 						const struct bpf_insn *si,
9423 						struct bpf_insn *insn)
9424 {
9425 	__u8 value_reg = si->dst_reg;
9426 	__u8 skb_reg = si->src_reg;
9427 
9428 #ifdef CONFIG_NET_XGRESS
9429 	/* If the tstamp_type is read,
9430 	 * the bpf prog is aware the tstamp could have delivery time.
9431 	 * Thus, read skb->tstamp as is if tstamp_type_access is true.
9432 	 */
9433 	if (!prog->tstamp_type_access) {
9434 		/* AX is needed because src_reg and dst_reg could be the same */
9435 		__u8 tmp_reg = BPF_REG_AX;
9436 
9437 		*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
9438 		*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg,
9439 					TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK);
9440 		*insn++ = BPF_JMP32_IMM(BPF_JNE, tmp_reg,
9441 					TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK, 2);
9442 		/* skb->tc_at_ingress && skb->tstamp_type,
9443 		 * read 0 as the (rcv) timestamp.
9444 		 */
9445 		*insn++ = BPF_MOV64_IMM(value_reg, 0);
9446 		*insn++ = BPF_JMP_A(1);
9447 	}
9448 #endif
9449 
9450 	*insn++ = BPF_LDX_MEM(BPF_DW, value_reg, skb_reg,
9451 			      offsetof(struct sk_buff, tstamp));
9452 	return insn;
9453 }
9454 
bpf_convert_tstamp_write(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)9455 static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog,
9456 						 const struct bpf_insn *si,
9457 						 struct bpf_insn *insn)
9458 {
9459 	__u8 value_reg = si->src_reg;
9460 	__u8 skb_reg = si->dst_reg;
9461 
9462 #ifdef CONFIG_NET_XGRESS
9463 	/* If the tstamp_type is read,
9464 	 * the bpf prog is aware the tstamp could have delivery time.
9465 	 * Thus, write skb->tstamp as is if tstamp_type_access is true.
9466 	 * Otherwise, writing at ingress will have to clear the
9467 	 * skb->tstamp_type bit also.
9468 	 */
9469 	if (!prog->tstamp_type_access) {
9470 		__u8 tmp_reg = BPF_REG_AX;
9471 
9472 		*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
9473 		/* Writing __sk_buff->tstamp as ingress, goto <clear> */
9474 		*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, TC_AT_INGRESS_MASK, 1);
9475 		/* goto <store> */
9476 		*insn++ = BPF_JMP_A(2);
9477 		/* <clear>: skb->tstamp_type */
9478 		*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_MONO_DELIVERY_TIME_MASK);
9479 		*insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, SKB_BF_MONO_TC_OFFSET);
9480 	}
9481 #endif
9482 
9483 	/* <store>: skb->tstamp = tstamp */
9484 	*insn++ = BPF_RAW_INSN(BPF_CLASS(si->code) | BPF_DW | BPF_MEM,
9485 			       skb_reg, value_reg, offsetof(struct sk_buff, tstamp), si->imm);
9486 	return insn;
9487 }
9488 
9489 #define BPF_EMIT_STORE(size, si, off)					\
9490 	BPF_RAW_INSN(BPF_CLASS((si)->code) | (size) | BPF_MEM,		\
9491 		     (si)->dst_reg, (si)->src_reg, (off), (si)->imm)
9492 
bpf_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9493 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
9494 				  const struct bpf_insn *si,
9495 				  struct bpf_insn *insn_buf,
9496 				  struct bpf_prog *prog, u32 *target_size)
9497 {
9498 	struct bpf_insn *insn = insn_buf;
9499 	int off;
9500 
9501 	switch (si->off) {
9502 	case offsetof(struct __sk_buff, len):
9503 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9504 				      bpf_target_off(struct sk_buff, len, 4,
9505 						     target_size));
9506 		break;
9507 
9508 	case offsetof(struct __sk_buff, protocol):
9509 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9510 				      bpf_target_off(struct sk_buff, protocol, 2,
9511 						     target_size));
9512 		break;
9513 
9514 	case offsetof(struct __sk_buff, vlan_proto):
9515 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9516 				      bpf_target_off(struct sk_buff, vlan_proto, 2,
9517 						     target_size));
9518 		break;
9519 
9520 	case offsetof(struct __sk_buff, priority):
9521 		if (type == BPF_WRITE)
9522 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9523 						 bpf_target_off(struct sk_buff, priority, 4,
9524 								target_size));
9525 		else
9526 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9527 					      bpf_target_off(struct sk_buff, priority, 4,
9528 							     target_size));
9529 		break;
9530 
9531 	case offsetof(struct __sk_buff, ingress_ifindex):
9532 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9533 				      bpf_target_off(struct sk_buff, skb_iif, 4,
9534 						     target_size));
9535 		break;
9536 
9537 	case offsetof(struct __sk_buff, ifindex):
9538 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
9539 				      si->dst_reg, si->src_reg,
9540 				      offsetof(struct sk_buff, dev));
9541 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9542 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9543 				      bpf_target_off(struct net_device, ifindex, 4,
9544 						     target_size));
9545 		break;
9546 
9547 	case offsetof(struct __sk_buff, hash):
9548 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9549 				      bpf_target_off(struct sk_buff, hash, 4,
9550 						     target_size));
9551 		break;
9552 
9553 	case offsetof(struct __sk_buff, mark):
9554 		if (type == BPF_WRITE)
9555 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9556 						 bpf_target_off(struct sk_buff, mark, 4,
9557 								target_size));
9558 		else
9559 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9560 					      bpf_target_off(struct sk_buff, mark, 4,
9561 							     target_size));
9562 		break;
9563 
9564 	case offsetof(struct __sk_buff, pkt_type):
9565 		*target_size = 1;
9566 		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
9567 				      PKT_TYPE_OFFSET);
9568 		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
9569 #ifdef __BIG_ENDIAN_BITFIELD
9570 		*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
9571 #endif
9572 		break;
9573 
9574 	case offsetof(struct __sk_buff, queue_mapping):
9575 		if (type == BPF_WRITE) {
9576 			u32 off = bpf_target_off(struct sk_buff, queue_mapping, 2, target_size);
9577 
9578 			if (BPF_CLASS(si->code) == BPF_ST && si->imm >= NO_QUEUE_MAPPING) {
9579 				*insn++ = BPF_JMP_A(0); /* noop */
9580 				break;
9581 			}
9582 
9583 			if (BPF_CLASS(si->code) == BPF_STX)
9584 				*insn++ = BPF_JMP_IMM(BPF_JGE, si->src_reg, NO_QUEUE_MAPPING, 1);
9585 			*insn++ = BPF_EMIT_STORE(BPF_H, si, off);
9586 		} else {
9587 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9588 					      bpf_target_off(struct sk_buff,
9589 							     queue_mapping,
9590 							     2, target_size));
9591 		}
9592 		break;
9593 
9594 	case offsetof(struct __sk_buff, vlan_present):
9595 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9596 				      bpf_target_off(struct sk_buff,
9597 						     vlan_all, 4, target_size));
9598 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9599 		*insn++ = BPF_ALU32_IMM(BPF_MOV, si->dst_reg, 1);
9600 		break;
9601 
9602 	case offsetof(struct __sk_buff, vlan_tci):
9603 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9604 				      bpf_target_off(struct sk_buff, vlan_tci, 2,
9605 						     target_size));
9606 		break;
9607 
9608 	case offsetof(struct __sk_buff, cb[0]) ...
9609 	     offsetofend(struct __sk_buff, cb[4]) - 1:
9610 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, data) < 20);
9611 		BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
9612 			      offsetof(struct qdisc_skb_cb, data)) %
9613 			     sizeof(__u64));
9614 
9615 		prog->cb_access = 1;
9616 		off  = si->off;
9617 		off -= offsetof(struct __sk_buff, cb[0]);
9618 		off += offsetof(struct sk_buff, cb);
9619 		off += offsetof(struct qdisc_skb_cb, data);
9620 		if (type == BPF_WRITE)
9621 			*insn++ = BPF_EMIT_STORE(BPF_SIZE(si->code), si, off);
9622 		else
9623 			*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
9624 					      si->src_reg, off);
9625 		break;
9626 
9627 	case offsetof(struct __sk_buff, tc_classid):
9628 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, tc_classid) != 2);
9629 
9630 		off  = si->off;
9631 		off -= offsetof(struct __sk_buff, tc_classid);
9632 		off += offsetof(struct sk_buff, cb);
9633 		off += offsetof(struct qdisc_skb_cb, tc_classid);
9634 		*target_size = 2;
9635 		if (type == BPF_WRITE)
9636 			*insn++ = BPF_EMIT_STORE(BPF_H, si, off);
9637 		else
9638 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
9639 					      si->src_reg, off);
9640 		break;
9641 
9642 	case offsetof(struct __sk_buff, data):
9643 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
9644 				      si->dst_reg, si->src_reg,
9645 				      offsetof(struct sk_buff, data));
9646 		break;
9647 
9648 	case offsetof(struct __sk_buff, data_meta):
9649 		off  = si->off;
9650 		off -= offsetof(struct __sk_buff, data_meta);
9651 		off += offsetof(struct sk_buff, cb);
9652 		off += offsetof(struct bpf_skb_data_end, data_meta);
9653 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9654 				      si->src_reg, off);
9655 		break;
9656 
9657 	case offsetof(struct __sk_buff, data_end):
9658 		off  = si->off;
9659 		off -= offsetof(struct __sk_buff, data_end);
9660 		off += offsetof(struct sk_buff, cb);
9661 		off += offsetof(struct bpf_skb_data_end, data_end);
9662 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9663 				      si->src_reg, off);
9664 		break;
9665 
9666 	case offsetof(struct __sk_buff, tc_index):
9667 #ifdef CONFIG_NET_SCHED
9668 		if (type == BPF_WRITE)
9669 			*insn++ = BPF_EMIT_STORE(BPF_H, si,
9670 						 bpf_target_off(struct sk_buff, tc_index, 2,
9671 								target_size));
9672 		else
9673 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9674 					      bpf_target_off(struct sk_buff, tc_index, 2,
9675 							     target_size));
9676 #else
9677 		*target_size = 2;
9678 		if (type == BPF_WRITE)
9679 			*insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
9680 		else
9681 			*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9682 #endif
9683 		break;
9684 
9685 	case offsetof(struct __sk_buff, napi_id):
9686 #if defined(CONFIG_NET_RX_BUSY_POLL)
9687 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9688 				      bpf_target_off(struct sk_buff, napi_id, 4,
9689 						     target_size));
9690 		*insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
9691 		*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9692 #else
9693 		*target_size = 4;
9694 		*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9695 #endif
9696 		break;
9697 	case offsetof(struct __sk_buff, family):
9698 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
9699 
9700 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9701 				      si->dst_reg, si->src_reg,
9702 				      offsetof(struct sk_buff, sk));
9703 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9704 				      bpf_target_off(struct sock_common,
9705 						     skc_family,
9706 						     2, target_size));
9707 		break;
9708 	case offsetof(struct __sk_buff, remote_ip4):
9709 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
9710 
9711 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9712 				      si->dst_reg, si->src_reg,
9713 				      offsetof(struct sk_buff, sk));
9714 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9715 				      bpf_target_off(struct sock_common,
9716 						     skc_daddr,
9717 						     4, target_size));
9718 		break;
9719 	case offsetof(struct __sk_buff, local_ip4):
9720 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9721 					  skc_rcv_saddr) != 4);
9722 
9723 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9724 				      si->dst_reg, si->src_reg,
9725 				      offsetof(struct sk_buff, sk));
9726 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9727 				      bpf_target_off(struct sock_common,
9728 						     skc_rcv_saddr,
9729 						     4, target_size));
9730 		break;
9731 	case offsetof(struct __sk_buff, remote_ip6[0]) ...
9732 	     offsetof(struct __sk_buff, remote_ip6[3]):
9733 #if IS_ENABLED(CONFIG_IPV6)
9734 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9735 					  skc_v6_daddr.s6_addr32[0]) != 4);
9736 
9737 		off = si->off;
9738 		off -= offsetof(struct __sk_buff, remote_ip6[0]);
9739 
9740 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9741 				      si->dst_reg, si->src_reg,
9742 				      offsetof(struct sk_buff, sk));
9743 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9744 				      offsetof(struct sock_common,
9745 					       skc_v6_daddr.s6_addr32[0]) +
9746 				      off);
9747 #else
9748 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9749 #endif
9750 		break;
9751 	case offsetof(struct __sk_buff, local_ip6[0]) ...
9752 	     offsetof(struct __sk_buff, local_ip6[3]):
9753 #if IS_ENABLED(CONFIG_IPV6)
9754 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9755 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
9756 
9757 		off = si->off;
9758 		off -= offsetof(struct __sk_buff, local_ip6[0]);
9759 
9760 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9761 				      si->dst_reg, si->src_reg,
9762 				      offsetof(struct sk_buff, sk));
9763 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9764 				      offsetof(struct sock_common,
9765 					       skc_v6_rcv_saddr.s6_addr32[0]) +
9766 				      off);
9767 #else
9768 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9769 #endif
9770 		break;
9771 
9772 	case offsetof(struct __sk_buff, remote_port):
9773 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
9774 
9775 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9776 				      si->dst_reg, si->src_reg,
9777 				      offsetof(struct sk_buff, sk));
9778 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9779 				      bpf_target_off(struct sock_common,
9780 						     skc_dport,
9781 						     2, target_size));
9782 #ifndef __BIG_ENDIAN_BITFIELD
9783 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
9784 #endif
9785 		break;
9786 
9787 	case offsetof(struct __sk_buff, local_port):
9788 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
9789 
9790 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9791 				      si->dst_reg, si->src_reg,
9792 				      offsetof(struct sk_buff, sk));
9793 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9794 				      bpf_target_off(struct sock_common,
9795 						     skc_num, 2, target_size));
9796 		break;
9797 
9798 	case offsetof(struct __sk_buff, tstamp):
9799 		BUILD_BUG_ON(sizeof_field(struct sk_buff, tstamp) != 8);
9800 
9801 		if (type == BPF_WRITE)
9802 			insn = bpf_convert_tstamp_write(prog, si, insn);
9803 		else
9804 			insn = bpf_convert_tstamp_read(prog, si, insn);
9805 		break;
9806 
9807 	case offsetof(struct __sk_buff, tstamp_type):
9808 		insn = bpf_convert_tstamp_type_read(si, insn);
9809 		break;
9810 
9811 	case offsetof(struct __sk_buff, gso_segs):
9812 		insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
9813 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_segs),
9814 				      si->dst_reg, si->dst_reg,
9815 				      bpf_target_off(struct skb_shared_info,
9816 						     gso_segs, 2,
9817 						     target_size));
9818 		break;
9819 	case offsetof(struct __sk_buff, gso_size):
9820 		insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
9821 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_size),
9822 				      si->dst_reg, si->dst_reg,
9823 				      bpf_target_off(struct skb_shared_info,
9824 						     gso_size, 2,
9825 						     target_size));
9826 		break;
9827 	case offsetof(struct __sk_buff, wire_len):
9828 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, pkt_len) != 4);
9829 
9830 		off = si->off;
9831 		off -= offsetof(struct __sk_buff, wire_len);
9832 		off += offsetof(struct sk_buff, cb);
9833 		off += offsetof(struct qdisc_skb_cb, pkt_len);
9834 		*target_size = 4;
9835 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
9836 		break;
9837 
9838 	case offsetof(struct __sk_buff, sk):
9839 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9840 				      si->dst_reg, si->src_reg,
9841 				      offsetof(struct sk_buff, sk));
9842 		break;
9843 	case offsetof(struct __sk_buff, hwtstamp):
9844 		BUILD_BUG_ON(sizeof_field(struct skb_shared_hwtstamps, hwtstamp) != 8);
9845 		BUILD_BUG_ON(offsetof(struct skb_shared_hwtstamps, hwtstamp) != 0);
9846 
9847 		insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
9848 		*insn++ = BPF_LDX_MEM(BPF_DW,
9849 				      si->dst_reg, si->dst_reg,
9850 				      bpf_target_off(struct skb_shared_info,
9851 						     hwtstamps, 8,
9852 						     target_size));
9853 		break;
9854 	}
9855 
9856 	return insn - insn_buf;
9857 }
9858 
bpf_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9859 u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
9860 				const struct bpf_insn *si,
9861 				struct bpf_insn *insn_buf,
9862 				struct bpf_prog *prog, u32 *target_size)
9863 {
9864 	struct bpf_insn *insn = insn_buf;
9865 	int off;
9866 
9867 	switch (si->off) {
9868 	case offsetof(struct bpf_sock, bound_dev_if):
9869 		BUILD_BUG_ON(sizeof_field(struct sock, sk_bound_dev_if) != 4);
9870 
9871 		if (type == BPF_WRITE)
9872 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9873 						 offsetof(struct sock, sk_bound_dev_if));
9874 		else
9875 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9876 				      offsetof(struct sock, sk_bound_dev_if));
9877 		break;
9878 
9879 	case offsetof(struct bpf_sock, mark):
9880 		BUILD_BUG_ON(sizeof_field(struct sock, sk_mark) != 4);
9881 
9882 		if (type == BPF_WRITE)
9883 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9884 						 offsetof(struct sock, sk_mark));
9885 		else
9886 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9887 				      offsetof(struct sock, sk_mark));
9888 		break;
9889 
9890 	case offsetof(struct bpf_sock, priority):
9891 		BUILD_BUG_ON(sizeof_field(struct sock, sk_priority) != 4);
9892 
9893 		if (type == BPF_WRITE)
9894 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9895 						 offsetof(struct sock, sk_priority));
9896 		else
9897 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9898 				      offsetof(struct sock, sk_priority));
9899 		break;
9900 
9901 	case offsetof(struct bpf_sock, family):
9902 		*insn++ = BPF_LDX_MEM(
9903 			BPF_FIELD_SIZEOF(struct sock_common, skc_family),
9904 			si->dst_reg, si->src_reg,
9905 			bpf_target_off(struct sock_common,
9906 				       skc_family,
9907 				       sizeof_field(struct sock_common,
9908 						    skc_family),
9909 				       target_size));
9910 		break;
9911 
9912 	case offsetof(struct bpf_sock, type):
9913 		*insn++ = BPF_LDX_MEM(
9914 			BPF_FIELD_SIZEOF(struct sock, sk_type),
9915 			si->dst_reg, si->src_reg,
9916 			bpf_target_off(struct sock, sk_type,
9917 				       sizeof_field(struct sock, sk_type),
9918 				       target_size));
9919 		break;
9920 
9921 	case offsetof(struct bpf_sock, protocol):
9922 		*insn++ = BPF_LDX_MEM(
9923 			BPF_FIELD_SIZEOF(struct sock, sk_protocol),
9924 			si->dst_reg, si->src_reg,
9925 			bpf_target_off(struct sock, sk_protocol,
9926 				       sizeof_field(struct sock, sk_protocol),
9927 				       target_size));
9928 		break;
9929 
9930 	case offsetof(struct bpf_sock, src_ip4):
9931 		*insn++ = BPF_LDX_MEM(
9932 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9933 			bpf_target_off(struct sock_common, skc_rcv_saddr,
9934 				       sizeof_field(struct sock_common,
9935 						    skc_rcv_saddr),
9936 				       target_size));
9937 		break;
9938 
9939 	case offsetof(struct bpf_sock, dst_ip4):
9940 		*insn++ = BPF_LDX_MEM(
9941 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9942 			bpf_target_off(struct sock_common, skc_daddr,
9943 				       sizeof_field(struct sock_common,
9944 						    skc_daddr),
9945 				       target_size));
9946 		break;
9947 
9948 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
9949 #if IS_ENABLED(CONFIG_IPV6)
9950 		off = si->off;
9951 		off -= offsetof(struct bpf_sock, src_ip6[0]);
9952 		*insn++ = BPF_LDX_MEM(
9953 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9954 			bpf_target_off(
9955 				struct sock_common,
9956 				skc_v6_rcv_saddr.s6_addr32[0],
9957 				sizeof_field(struct sock_common,
9958 					     skc_v6_rcv_saddr.s6_addr32[0]),
9959 				target_size) + off);
9960 #else
9961 		(void)off;
9962 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9963 #endif
9964 		break;
9965 
9966 	case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
9967 #if IS_ENABLED(CONFIG_IPV6)
9968 		off = si->off;
9969 		off -= offsetof(struct bpf_sock, dst_ip6[0]);
9970 		*insn++ = BPF_LDX_MEM(
9971 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9972 			bpf_target_off(struct sock_common,
9973 				       skc_v6_daddr.s6_addr32[0],
9974 				       sizeof_field(struct sock_common,
9975 						    skc_v6_daddr.s6_addr32[0]),
9976 				       target_size) + off);
9977 #else
9978 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9979 		*target_size = 4;
9980 #endif
9981 		break;
9982 
9983 	case offsetof(struct bpf_sock, src_port):
9984 		*insn++ = BPF_LDX_MEM(
9985 			BPF_FIELD_SIZEOF(struct sock_common, skc_num),
9986 			si->dst_reg, si->src_reg,
9987 			bpf_target_off(struct sock_common, skc_num,
9988 				       sizeof_field(struct sock_common,
9989 						    skc_num),
9990 				       target_size));
9991 		break;
9992 
9993 	case offsetof(struct bpf_sock, dst_port):
9994 		*insn++ = BPF_LDX_MEM(
9995 			BPF_FIELD_SIZEOF(struct sock_common, skc_dport),
9996 			si->dst_reg, si->src_reg,
9997 			bpf_target_off(struct sock_common, skc_dport,
9998 				       sizeof_field(struct sock_common,
9999 						    skc_dport),
10000 				       target_size));
10001 		break;
10002 
10003 	case offsetof(struct bpf_sock, state):
10004 		*insn++ = BPF_LDX_MEM(
10005 			BPF_FIELD_SIZEOF(struct sock_common, skc_state),
10006 			si->dst_reg, si->src_reg,
10007 			bpf_target_off(struct sock_common, skc_state,
10008 				       sizeof_field(struct sock_common,
10009 						    skc_state),
10010 				       target_size));
10011 		break;
10012 	case offsetof(struct bpf_sock, rx_queue_mapping):
10013 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
10014 		*insn++ = BPF_LDX_MEM(
10015 			BPF_FIELD_SIZEOF(struct sock, sk_rx_queue_mapping),
10016 			si->dst_reg, si->src_reg,
10017 			bpf_target_off(struct sock, sk_rx_queue_mapping,
10018 				       sizeof_field(struct sock,
10019 						    sk_rx_queue_mapping),
10020 				       target_size));
10021 		*insn++ = BPF_JMP_IMM(BPF_JNE, si->dst_reg, NO_QUEUE_MAPPING,
10022 				      1);
10023 		*insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
10024 #else
10025 		*insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
10026 		*target_size = 2;
10027 #endif
10028 		break;
10029 	}
10030 
10031 	return insn - insn_buf;
10032 }
10033 
tc_cls_act_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10034 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
10035 					 const struct bpf_insn *si,
10036 					 struct bpf_insn *insn_buf,
10037 					 struct bpf_prog *prog, u32 *target_size)
10038 {
10039 	struct bpf_insn *insn = insn_buf;
10040 
10041 	switch (si->off) {
10042 	case offsetof(struct __sk_buff, ifindex):
10043 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
10044 				      si->dst_reg, si->src_reg,
10045 				      offsetof(struct sk_buff, dev));
10046 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10047 				      bpf_target_off(struct net_device, ifindex, 4,
10048 						     target_size));
10049 		break;
10050 	default:
10051 		return bpf_convert_ctx_access(type, si, insn_buf, prog,
10052 					      target_size);
10053 	}
10054 
10055 	return insn - insn_buf;
10056 }
10057 
xdp_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10058 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
10059 				  const struct bpf_insn *si,
10060 				  struct bpf_insn *insn_buf,
10061 				  struct bpf_prog *prog, u32 *target_size)
10062 {
10063 	struct bpf_insn *insn = insn_buf;
10064 
10065 	switch (si->off) {
10066 	case offsetof(struct xdp_md, data):
10067 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
10068 				      si->dst_reg, si->src_reg,
10069 				      offsetof(struct xdp_buff, data));
10070 		break;
10071 	case offsetof(struct xdp_md, data_meta):
10072 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
10073 				      si->dst_reg, si->src_reg,
10074 				      offsetof(struct xdp_buff, data_meta));
10075 		break;
10076 	case offsetof(struct xdp_md, data_end):
10077 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
10078 				      si->dst_reg, si->src_reg,
10079 				      offsetof(struct xdp_buff, data_end));
10080 		break;
10081 	case offsetof(struct xdp_md, ingress_ifindex):
10082 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
10083 				      si->dst_reg, si->src_reg,
10084 				      offsetof(struct xdp_buff, rxq));
10085 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
10086 				      si->dst_reg, si->dst_reg,
10087 				      offsetof(struct xdp_rxq_info, dev));
10088 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10089 				      offsetof(struct net_device, ifindex));
10090 		break;
10091 	case offsetof(struct xdp_md, rx_queue_index):
10092 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
10093 				      si->dst_reg, si->src_reg,
10094 				      offsetof(struct xdp_buff, rxq));
10095 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10096 				      offsetof(struct xdp_rxq_info,
10097 					       queue_index));
10098 		break;
10099 	case offsetof(struct xdp_md, egress_ifindex):
10100 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, txq),
10101 				      si->dst_reg, si->src_reg,
10102 				      offsetof(struct xdp_buff, txq));
10103 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_txq_info, dev),
10104 				      si->dst_reg, si->dst_reg,
10105 				      offsetof(struct xdp_txq_info, dev));
10106 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10107 				      offsetof(struct net_device, ifindex));
10108 		break;
10109 	}
10110 
10111 	return insn - insn_buf;
10112 }
10113 
10114 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
10115  * context Structure, F is Field in context structure that contains a pointer
10116  * to Nested Structure of type NS that has the field NF.
10117  *
10118  * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
10119  * sure that SIZE is not greater than actual size of S.F.NF.
10120  *
10121  * If offset OFF is provided, the load happens from that offset relative to
10122  * offset of NF.
10123  */
10124 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF)	       \
10125 	do {								       \
10126 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg,     \
10127 				      si->src_reg, offsetof(S, F));	       \
10128 		*insn++ = BPF_LDX_MEM(					       \
10129 			SIZE, si->dst_reg, si->dst_reg,			       \
10130 			bpf_target_off(NS, NF, sizeof_field(NS, NF),	       \
10131 				       target_size)			       \
10132 				+ OFF);					       \
10133 	} while (0)
10134 
10135 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF)			       \
10136 	SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF,		       \
10137 					     BPF_FIELD_SIZEOF(NS, NF), 0)
10138 
10139 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
10140  * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
10141  *
10142  * In addition it uses Temporary Field TF (member of struct S) as the 3rd
10143  * "register" since two registers available in convert_ctx_access are not
10144  * enough: we can't override neither SRC, since it contains value to store, nor
10145  * DST since it contains pointer to context that may be used by later
10146  * instructions. But we need a temporary place to save pointer to nested
10147  * structure whose field we want to store to.
10148  */
10149 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, OFF, TF)	       \
10150 	do {								       \
10151 		int tmp_reg = BPF_REG_9;				       \
10152 		if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)	       \
10153 			--tmp_reg;					       \
10154 		if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)	       \
10155 			--tmp_reg;					       \
10156 		*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg,	       \
10157 				      offsetof(S, TF));			       \
10158 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg,	       \
10159 				      si->dst_reg, offsetof(S, F));	       \
10160 		*insn++ = BPF_RAW_INSN(SIZE | BPF_MEM | BPF_CLASS(si->code),   \
10161 				       tmp_reg, si->src_reg,		       \
10162 			bpf_target_off(NS, NF, sizeof_field(NS, NF),	       \
10163 				       target_size)			       \
10164 				       + OFF,				       \
10165 				       si->imm);			       \
10166 		*insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg,	       \
10167 				      offsetof(S, TF));			       \
10168 	} while (0)
10169 
10170 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
10171 						      TF)		       \
10172 	do {								       \
10173 		if (type == BPF_WRITE) {				       \
10174 			SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE,   \
10175 							 OFF, TF);	       \
10176 		} else {						       \
10177 			SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(		       \
10178 				S, NS, F, NF, SIZE, OFF);  \
10179 		}							       \
10180 	} while (0)
10181 
10182 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF)		       \
10183 	SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(			       \
10184 		S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
10185 
sock_addr_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10186 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
10187 					const struct bpf_insn *si,
10188 					struct bpf_insn *insn_buf,
10189 					struct bpf_prog *prog, u32 *target_size)
10190 {
10191 	int off, port_size = sizeof_field(struct sockaddr_in6, sin6_port);
10192 	struct bpf_insn *insn = insn_buf;
10193 
10194 	switch (si->off) {
10195 	case offsetof(struct bpf_sock_addr, user_family):
10196 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10197 					    struct sockaddr, uaddr, sa_family);
10198 		break;
10199 
10200 	case offsetof(struct bpf_sock_addr, user_ip4):
10201 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10202 			struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
10203 			sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
10204 		break;
10205 
10206 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
10207 		off = si->off;
10208 		off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
10209 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10210 			struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
10211 			sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
10212 			tmp_reg);
10213 		break;
10214 
10215 	case offsetof(struct bpf_sock_addr, user_port):
10216 		/* To get port we need to know sa_family first and then treat
10217 		 * sockaddr as either sockaddr_in or sockaddr_in6.
10218 		 * Though we can simplify since port field has same offset and
10219 		 * size in both structures.
10220 		 * Here we check this invariant and use just one of the
10221 		 * structures if it's true.
10222 		 */
10223 		BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
10224 			     offsetof(struct sockaddr_in6, sin6_port));
10225 		BUILD_BUG_ON(sizeof_field(struct sockaddr_in, sin_port) !=
10226 			     sizeof_field(struct sockaddr_in6, sin6_port));
10227 		/* Account for sin6_port being smaller than user_port. */
10228 		port_size = min(port_size, BPF_LDST_BYTES(si));
10229 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10230 			struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
10231 			sin6_port, bytes_to_bpf_size(port_size), 0, tmp_reg);
10232 		break;
10233 
10234 	case offsetof(struct bpf_sock_addr, family):
10235 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10236 					    struct sock, sk, sk_family);
10237 		break;
10238 
10239 	case offsetof(struct bpf_sock_addr, type):
10240 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10241 					    struct sock, sk, sk_type);
10242 		break;
10243 
10244 	case offsetof(struct bpf_sock_addr, protocol):
10245 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10246 					    struct sock, sk, sk_protocol);
10247 		break;
10248 
10249 	case offsetof(struct bpf_sock_addr, msg_src_ip4):
10250 		/* Treat t_ctx as struct in_addr for msg_src_ip4. */
10251 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10252 			struct bpf_sock_addr_kern, struct in_addr, t_ctx,
10253 			s_addr, BPF_SIZE(si->code), 0, tmp_reg);
10254 		break;
10255 
10256 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
10257 				msg_src_ip6[3]):
10258 		off = si->off;
10259 		off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
10260 		/* Treat t_ctx as struct in6_addr for msg_src_ip6. */
10261 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10262 			struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
10263 			s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
10264 		break;
10265 	case offsetof(struct bpf_sock_addr, sk):
10266 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk),
10267 				      si->dst_reg, si->src_reg,
10268 				      offsetof(struct bpf_sock_addr_kern, sk));
10269 		break;
10270 	}
10271 
10272 	return insn - insn_buf;
10273 }
10274 
sock_ops_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10275 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
10276 				       const struct bpf_insn *si,
10277 				       struct bpf_insn *insn_buf,
10278 				       struct bpf_prog *prog,
10279 				       u32 *target_size)
10280 {
10281 	struct bpf_insn *insn = insn_buf;
10282 	int off;
10283 
10284 /* Helper macro for adding read access to tcp_sock or sock fields. */
10285 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)			      \
10286 	do {								      \
10287 		int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 2;     \
10288 		BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >		      \
10289 			     sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
10290 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10291 			reg--;						      \
10292 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10293 			reg--;						      \
10294 		if (si->dst_reg == si->src_reg) {			      \
10295 			*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,	      \
10296 					  offsetof(struct bpf_sock_ops_kern,  \
10297 					  temp));			      \
10298 			fullsock_reg = reg;				      \
10299 			jmp += 2;					      \
10300 		}							      \
10301 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10302 						struct bpf_sock_ops_kern,     \
10303 						is_fullsock),		      \
10304 				      fullsock_reg, si->src_reg,	      \
10305 				      offsetof(struct bpf_sock_ops_kern,      \
10306 					       is_fullsock));		      \
10307 		*insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);	      \
10308 		if (si->dst_reg == si->src_reg)				      \
10309 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10310 				      offsetof(struct bpf_sock_ops_kern,      \
10311 				      temp));				      \
10312 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10313 						struct bpf_sock_ops_kern, sk),\
10314 				      si->dst_reg, si->src_reg,		      \
10315 				      offsetof(struct bpf_sock_ops_kern, sk));\
10316 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ,		      \
10317 						       OBJ_FIELD),	      \
10318 				      si->dst_reg, si->dst_reg,		      \
10319 				      offsetof(OBJ, OBJ_FIELD));	      \
10320 		if (si->dst_reg == si->src_reg)	{			      \
10321 			*insn++ = BPF_JMP_A(1);				      \
10322 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10323 				      offsetof(struct bpf_sock_ops_kern,      \
10324 				      temp));				      \
10325 		}							      \
10326 	} while (0)
10327 
10328 #define SOCK_OPS_GET_SK()							      \
10329 	do {								      \
10330 		int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 1;     \
10331 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10332 			reg--;						      \
10333 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10334 			reg--;						      \
10335 		if (si->dst_reg == si->src_reg) {			      \
10336 			*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,	      \
10337 					  offsetof(struct bpf_sock_ops_kern,  \
10338 					  temp));			      \
10339 			fullsock_reg = reg;				      \
10340 			jmp += 2;					      \
10341 		}							      \
10342 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10343 						struct bpf_sock_ops_kern,     \
10344 						is_fullsock),		      \
10345 				      fullsock_reg, si->src_reg,	      \
10346 				      offsetof(struct bpf_sock_ops_kern,      \
10347 					       is_fullsock));		      \
10348 		*insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);	      \
10349 		if (si->dst_reg == si->src_reg)				      \
10350 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10351 				      offsetof(struct bpf_sock_ops_kern,      \
10352 				      temp));				      \
10353 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10354 						struct bpf_sock_ops_kern, sk),\
10355 				      si->dst_reg, si->src_reg,		      \
10356 				      offsetof(struct bpf_sock_ops_kern, sk));\
10357 		if (si->dst_reg == si->src_reg)	{			      \
10358 			*insn++ = BPF_JMP_A(1);				      \
10359 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10360 				      offsetof(struct bpf_sock_ops_kern,      \
10361 				      temp));				      \
10362 		}							      \
10363 	} while (0)
10364 
10365 #define SOCK_OPS_GET_TCP_SOCK_FIELD(FIELD) \
10366 		SOCK_OPS_GET_FIELD(FIELD, FIELD, struct tcp_sock)
10367 
10368 /* Helper macro for adding write access to tcp_sock or sock fields.
10369  * The macro is called with two registers, dst_reg which contains a pointer
10370  * to ctx (context) and src_reg which contains the value that should be
10371  * stored. However, we need an additional register since we cannot overwrite
10372  * dst_reg because it may be used later in the program.
10373  * Instead we "borrow" one of the other register. We first save its value
10374  * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
10375  * it at the end of the macro.
10376  */
10377 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)			      \
10378 	do {								      \
10379 		int reg = BPF_REG_9;					      \
10380 		BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >		      \
10381 			     sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
10382 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10383 			reg--;						      \
10384 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10385 			reg--;						      \
10386 		*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg,		      \
10387 				      offsetof(struct bpf_sock_ops_kern,      \
10388 					       temp));			      \
10389 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10390 						struct bpf_sock_ops_kern,     \
10391 						is_fullsock),		      \
10392 				      reg, si->dst_reg,			      \
10393 				      offsetof(struct bpf_sock_ops_kern,      \
10394 					       is_fullsock));		      \
10395 		*insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2);		      \
10396 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10397 						struct bpf_sock_ops_kern, sk),\
10398 				      reg, si->dst_reg,			      \
10399 				      offsetof(struct bpf_sock_ops_kern, sk));\
10400 		*insn++ = BPF_RAW_INSN(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD) |     \
10401 				       BPF_MEM | BPF_CLASS(si->code),	      \
10402 				       reg, si->src_reg,		      \
10403 				       offsetof(OBJ, OBJ_FIELD),	      \
10404 				       si->imm);			      \
10405 		*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg,		      \
10406 				      offsetof(struct bpf_sock_ops_kern,      \
10407 					       temp));			      \
10408 	} while (0)
10409 
10410 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE)	      \
10411 	do {								      \
10412 		if (TYPE == BPF_WRITE)					      \
10413 			SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
10414 		else							      \
10415 			SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
10416 	} while (0)
10417 
10418 	switch (si->off) {
10419 	case offsetof(struct bpf_sock_ops, op):
10420 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10421 						       op),
10422 				      si->dst_reg, si->src_reg,
10423 				      offsetof(struct bpf_sock_ops_kern, op));
10424 		break;
10425 
10426 	case offsetof(struct bpf_sock_ops, replylong[0]) ...
10427 	     offsetof(struct bpf_sock_ops, replylong[3]):
10428 		BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, reply) !=
10429 			     sizeof_field(struct bpf_sock_ops_kern, reply));
10430 		BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, replylong) !=
10431 			     sizeof_field(struct bpf_sock_ops_kern, replylong));
10432 		off = si->off;
10433 		off -= offsetof(struct bpf_sock_ops, replylong[0]);
10434 		off += offsetof(struct bpf_sock_ops_kern, replylong[0]);
10435 		if (type == BPF_WRITE)
10436 			*insn++ = BPF_EMIT_STORE(BPF_W, si, off);
10437 		else
10438 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
10439 					      off);
10440 		break;
10441 
10442 	case offsetof(struct bpf_sock_ops, family):
10443 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
10444 
10445 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10446 					      struct bpf_sock_ops_kern, sk),
10447 				      si->dst_reg, si->src_reg,
10448 				      offsetof(struct bpf_sock_ops_kern, sk));
10449 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10450 				      offsetof(struct sock_common, skc_family));
10451 		break;
10452 
10453 	case offsetof(struct bpf_sock_ops, remote_ip4):
10454 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10455 
10456 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10457 						struct bpf_sock_ops_kern, sk),
10458 				      si->dst_reg, si->src_reg,
10459 				      offsetof(struct bpf_sock_ops_kern, sk));
10460 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10461 				      offsetof(struct sock_common, skc_daddr));
10462 		break;
10463 
10464 	case offsetof(struct bpf_sock_ops, local_ip4):
10465 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10466 					  skc_rcv_saddr) != 4);
10467 
10468 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10469 					      struct bpf_sock_ops_kern, sk),
10470 				      si->dst_reg, si->src_reg,
10471 				      offsetof(struct bpf_sock_ops_kern, sk));
10472 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10473 				      offsetof(struct sock_common,
10474 					       skc_rcv_saddr));
10475 		break;
10476 
10477 	case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
10478 	     offsetof(struct bpf_sock_ops, remote_ip6[3]):
10479 #if IS_ENABLED(CONFIG_IPV6)
10480 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10481 					  skc_v6_daddr.s6_addr32[0]) != 4);
10482 
10483 		off = si->off;
10484 		off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
10485 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10486 						struct bpf_sock_ops_kern, sk),
10487 				      si->dst_reg, si->src_reg,
10488 				      offsetof(struct bpf_sock_ops_kern, sk));
10489 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10490 				      offsetof(struct sock_common,
10491 					       skc_v6_daddr.s6_addr32[0]) +
10492 				      off);
10493 #else
10494 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10495 #endif
10496 		break;
10497 
10498 	case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
10499 	     offsetof(struct bpf_sock_ops, local_ip6[3]):
10500 #if IS_ENABLED(CONFIG_IPV6)
10501 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10502 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10503 
10504 		off = si->off;
10505 		off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
10506 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10507 						struct bpf_sock_ops_kern, sk),
10508 				      si->dst_reg, si->src_reg,
10509 				      offsetof(struct bpf_sock_ops_kern, sk));
10510 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10511 				      offsetof(struct sock_common,
10512 					       skc_v6_rcv_saddr.s6_addr32[0]) +
10513 				      off);
10514 #else
10515 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10516 #endif
10517 		break;
10518 
10519 	case offsetof(struct bpf_sock_ops, remote_port):
10520 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10521 
10522 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10523 						struct bpf_sock_ops_kern, sk),
10524 				      si->dst_reg, si->src_reg,
10525 				      offsetof(struct bpf_sock_ops_kern, sk));
10526 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10527 				      offsetof(struct sock_common, skc_dport));
10528 #ifndef __BIG_ENDIAN_BITFIELD
10529 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10530 #endif
10531 		break;
10532 
10533 	case offsetof(struct bpf_sock_ops, local_port):
10534 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10535 
10536 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10537 						struct bpf_sock_ops_kern, sk),
10538 				      si->dst_reg, si->src_reg,
10539 				      offsetof(struct bpf_sock_ops_kern, sk));
10540 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10541 				      offsetof(struct sock_common, skc_num));
10542 		break;
10543 
10544 	case offsetof(struct bpf_sock_ops, is_fullsock):
10545 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10546 						struct bpf_sock_ops_kern,
10547 						is_fullsock),
10548 				      si->dst_reg, si->src_reg,
10549 				      offsetof(struct bpf_sock_ops_kern,
10550 					       is_fullsock));
10551 		break;
10552 
10553 	case offsetof(struct bpf_sock_ops, state):
10554 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_state) != 1);
10555 
10556 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10557 						struct bpf_sock_ops_kern, sk),
10558 				      si->dst_reg, si->src_reg,
10559 				      offsetof(struct bpf_sock_ops_kern, sk));
10560 		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
10561 				      offsetof(struct sock_common, skc_state));
10562 		break;
10563 
10564 	case offsetof(struct bpf_sock_ops, rtt_min):
10565 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
10566 			     sizeof(struct minmax));
10567 		BUILD_BUG_ON(sizeof(struct minmax) <
10568 			     sizeof(struct minmax_sample));
10569 
10570 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10571 						struct bpf_sock_ops_kern, sk),
10572 				      si->dst_reg, si->src_reg,
10573 				      offsetof(struct bpf_sock_ops_kern, sk));
10574 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10575 				      offsetof(struct tcp_sock, rtt_min) +
10576 				      sizeof_field(struct minmax_sample, t));
10577 		break;
10578 
10579 	case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
10580 		SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
10581 				   struct tcp_sock);
10582 		break;
10583 
10584 	case offsetof(struct bpf_sock_ops, sk_txhash):
10585 		SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
10586 					  struct sock, type);
10587 		break;
10588 	case offsetof(struct bpf_sock_ops, snd_cwnd):
10589 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_cwnd);
10590 		break;
10591 	case offsetof(struct bpf_sock_ops, srtt_us):
10592 		SOCK_OPS_GET_TCP_SOCK_FIELD(srtt_us);
10593 		break;
10594 	case offsetof(struct bpf_sock_ops, snd_ssthresh):
10595 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_ssthresh);
10596 		break;
10597 	case offsetof(struct bpf_sock_ops, rcv_nxt):
10598 		SOCK_OPS_GET_TCP_SOCK_FIELD(rcv_nxt);
10599 		break;
10600 	case offsetof(struct bpf_sock_ops, snd_nxt):
10601 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_nxt);
10602 		break;
10603 	case offsetof(struct bpf_sock_ops, snd_una):
10604 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_una);
10605 		break;
10606 	case offsetof(struct bpf_sock_ops, mss_cache):
10607 		SOCK_OPS_GET_TCP_SOCK_FIELD(mss_cache);
10608 		break;
10609 	case offsetof(struct bpf_sock_ops, ecn_flags):
10610 		SOCK_OPS_GET_TCP_SOCK_FIELD(ecn_flags);
10611 		break;
10612 	case offsetof(struct bpf_sock_ops, rate_delivered):
10613 		SOCK_OPS_GET_TCP_SOCK_FIELD(rate_delivered);
10614 		break;
10615 	case offsetof(struct bpf_sock_ops, rate_interval_us):
10616 		SOCK_OPS_GET_TCP_SOCK_FIELD(rate_interval_us);
10617 		break;
10618 	case offsetof(struct bpf_sock_ops, packets_out):
10619 		SOCK_OPS_GET_TCP_SOCK_FIELD(packets_out);
10620 		break;
10621 	case offsetof(struct bpf_sock_ops, retrans_out):
10622 		SOCK_OPS_GET_TCP_SOCK_FIELD(retrans_out);
10623 		break;
10624 	case offsetof(struct bpf_sock_ops, total_retrans):
10625 		SOCK_OPS_GET_TCP_SOCK_FIELD(total_retrans);
10626 		break;
10627 	case offsetof(struct bpf_sock_ops, segs_in):
10628 		SOCK_OPS_GET_TCP_SOCK_FIELD(segs_in);
10629 		break;
10630 	case offsetof(struct bpf_sock_ops, data_segs_in):
10631 		SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_in);
10632 		break;
10633 	case offsetof(struct bpf_sock_ops, segs_out):
10634 		SOCK_OPS_GET_TCP_SOCK_FIELD(segs_out);
10635 		break;
10636 	case offsetof(struct bpf_sock_ops, data_segs_out):
10637 		SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_out);
10638 		break;
10639 	case offsetof(struct bpf_sock_ops, lost_out):
10640 		SOCK_OPS_GET_TCP_SOCK_FIELD(lost_out);
10641 		break;
10642 	case offsetof(struct bpf_sock_ops, sacked_out):
10643 		SOCK_OPS_GET_TCP_SOCK_FIELD(sacked_out);
10644 		break;
10645 	case offsetof(struct bpf_sock_ops, bytes_received):
10646 		SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_received);
10647 		break;
10648 	case offsetof(struct bpf_sock_ops, bytes_acked):
10649 		SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_acked);
10650 		break;
10651 	case offsetof(struct bpf_sock_ops, sk):
10652 		SOCK_OPS_GET_SK();
10653 		break;
10654 	case offsetof(struct bpf_sock_ops, skb_data_end):
10655 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10656 						       skb_data_end),
10657 				      si->dst_reg, si->src_reg,
10658 				      offsetof(struct bpf_sock_ops_kern,
10659 					       skb_data_end));
10660 		break;
10661 	case offsetof(struct bpf_sock_ops, skb_data):
10662 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10663 						       skb),
10664 				      si->dst_reg, si->src_reg,
10665 				      offsetof(struct bpf_sock_ops_kern,
10666 					       skb));
10667 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10668 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10669 				      si->dst_reg, si->dst_reg,
10670 				      offsetof(struct sk_buff, data));
10671 		break;
10672 	case offsetof(struct bpf_sock_ops, skb_len):
10673 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10674 						       skb),
10675 				      si->dst_reg, si->src_reg,
10676 				      offsetof(struct bpf_sock_ops_kern,
10677 					       skb));
10678 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10679 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10680 				      si->dst_reg, si->dst_reg,
10681 				      offsetof(struct sk_buff, len));
10682 		break;
10683 	case offsetof(struct bpf_sock_ops, skb_tcp_flags):
10684 		off = offsetof(struct sk_buff, cb);
10685 		off += offsetof(struct tcp_skb_cb, tcp_flags);
10686 		*target_size = sizeof_field(struct tcp_skb_cb, tcp_flags);
10687 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10688 						       skb),
10689 				      si->dst_reg, si->src_reg,
10690 				      offsetof(struct bpf_sock_ops_kern,
10691 					       skb));
10692 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10693 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_skb_cb,
10694 						       tcp_flags),
10695 				      si->dst_reg, si->dst_reg, off);
10696 		break;
10697 	case offsetof(struct bpf_sock_ops, skb_hwtstamp): {
10698 		struct bpf_insn *jmp_on_null_skb;
10699 
10700 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10701 						       skb),
10702 				      si->dst_reg, si->src_reg,
10703 				      offsetof(struct bpf_sock_ops_kern,
10704 					       skb));
10705 		/* Reserve one insn to test skb == NULL */
10706 		jmp_on_null_skb = insn++;
10707 		insn = bpf_convert_shinfo_access(si->dst_reg, si->dst_reg, insn);
10708 		*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
10709 				      bpf_target_off(struct skb_shared_info,
10710 						     hwtstamps, 8,
10711 						     target_size));
10712 		*jmp_on_null_skb = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0,
10713 					       insn - jmp_on_null_skb - 1);
10714 		break;
10715 	}
10716 	}
10717 	return insn - insn_buf;
10718 }
10719 
10720 /* data_end = skb->data + skb_headlen() */
bpf_convert_data_end_access(const struct bpf_insn * si,struct bpf_insn * insn)10721 static struct bpf_insn *bpf_convert_data_end_access(const struct bpf_insn *si,
10722 						    struct bpf_insn *insn)
10723 {
10724 	int reg;
10725 	int temp_reg_off = offsetof(struct sk_buff, cb) +
10726 			   offsetof(struct sk_skb_cb, temp_reg);
10727 
10728 	if (si->src_reg == si->dst_reg) {
10729 		/* We need an extra register, choose and save a register. */
10730 		reg = BPF_REG_9;
10731 		if (si->src_reg == reg || si->dst_reg == reg)
10732 			reg--;
10733 		if (si->src_reg == reg || si->dst_reg == reg)
10734 			reg--;
10735 		*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, temp_reg_off);
10736 	} else {
10737 		reg = si->dst_reg;
10738 	}
10739 
10740 	/* reg = skb->data */
10741 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10742 			      reg, si->src_reg,
10743 			      offsetof(struct sk_buff, data));
10744 	/* AX = skb->len */
10745 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10746 			      BPF_REG_AX, si->src_reg,
10747 			      offsetof(struct sk_buff, len));
10748 	/* reg = skb->data + skb->len */
10749 	*insn++ = BPF_ALU64_REG(BPF_ADD, reg, BPF_REG_AX);
10750 	/* AX = skb->data_len */
10751 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data_len),
10752 			      BPF_REG_AX, si->src_reg,
10753 			      offsetof(struct sk_buff, data_len));
10754 
10755 	/* reg = skb->data + skb->len - skb->data_len */
10756 	*insn++ = BPF_ALU64_REG(BPF_SUB, reg, BPF_REG_AX);
10757 
10758 	if (si->src_reg == si->dst_reg) {
10759 		/* Restore the saved register */
10760 		*insn++ = BPF_MOV64_REG(BPF_REG_AX, si->src_reg);
10761 		*insn++ = BPF_MOV64_REG(si->dst_reg, reg);
10762 		*insn++ = BPF_LDX_MEM(BPF_DW, reg, BPF_REG_AX, temp_reg_off);
10763 	}
10764 
10765 	return insn;
10766 }
10767 
sk_skb_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10768 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
10769 				     const struct bpf_insn *si,
10770 				     struct bpf_insn *insn_buf,
10771 				     struct bpf_prog *prog, u32 *target_size)
10772 {
10773 	struct bpf_insn *insn = insn_buf;
10774 	int off;
10775 
10776 	switch (si->off) {
10777 	case offsetof(struct __sk_buff, data_end):
10778 		insn = bpf_convert_data_end_access(si, insn);
10779 		break;
10780 	case offsetof(struct __sk_buff, cb[0]) ...
10781 	     offsetofend(struct __sk_buff, cb[4]) - 1:
10782 		BUILD_BUG_ON(sizeof_field(struct sk_skb_cb, data) < 20);
10783 		BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
10784 			      offsetof(struct sk_skb_cb, data)) %
10785 			     sizeof(__u64));
10786 
10787 		prog->cb_access = 1;
10788 		off  = si->off;
10789 		off -= offsetof(struct __sk_buff, cb[0]);
10790 		off += offsetof(struct sk_buff, cb);
10791 		off += offsetof(struct sk_skb_cb, data);
10792 		if (type == BPF_WRITE)
10793 			*insn++ = BPF_EMIT_STORE(BPF_SIZE(si->code), si, off);
10794 		else
10795 			*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
10796 					      si->src_reg, off);
10797 		break;
10798 
10799 
10800 	default:
10801 		return bpf_convert_ctx_access(type, si, insn_buf, prog,
10802 					      target_size);
10803 	}
10804 
10805 	return insn - insn_buf;
10806 }
10807 
sk_msg_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10808 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
10809 				     const struct bpf_insn *si,
10810 				     struct bpf_insn *insn_buf,
10811 				     struct bpf_prog *prog, u32 *target_size)
10812 {
10813 	struct bpf_insn *insn = insn_buf;
10814 #if IS_ENABLED(CONFIG_IPV6)
10815 	int off;
10816 #endif
10817 
10818 	/* convert ctx uses the fact sg element is first in struct */
10819 	BUILD_BUG_ON(offsetof(struct sk_msg, sg) != 0);
10820 
10821 	switch (si->off) {
10822 	case offsetof(struct sk_msg_md, data):
10823 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data),
10824 				      si->dst_reg, si->src_reg,
10825 				      offsetof(struct sk_msg, data));
10826 		break;
10827 	case offsetof(struct sk_msg_md, data_end):
10828 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end),
10829 				      si->dst_reg, si->src_reg,
10830 				      offsetof(struct sk_msg, data_end));
10831 		break;
10832 	case offsetof(struct sk_msg_md, family):
10833 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
10834 
10835 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10836 					      struct sk_msg, sk),
10837 				      si->dst_reg, si->src_reg,
10838 				      offsetof(struct sk_msg, sk));
10839 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10840 				      offsetof(struct sock_common, skc_family));
10841 		break;
10842 
10843 	case offsetof(struct sk_msg_md, remote_ip4):
10844 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10845 
10846 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10847 						struct sk_msg, sk),
10848 				      si->dst_reg, si->src_reg,
10849 				      offsetof(struct sk_msg, sk));
10850 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10851 				      offsetof(struct sock_common, skc_daddr));
10852 		break;
10853 
10854 	case offsetof(struct sk_msg_md, local_ip4):
10855 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10856 					  skc_rcv_saddr) != 4);
10857 
10858 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10859 					      struct sk_msg, sk),
10860 				      si->dst_reg, si->src_reg,
10861 				      offsetof(struct sk_msg, sk));
10862 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10863 				      offsetof(struct sock_common,
10864 					       skc_rcv_saddr));
10865 		break;
10866 
10867 	case offsetof(struct sk_msg_md, remote_ip6[0]) ...
10868 	     offsetof(struct sk_msg_md, remote_ip6[3]):
10869 #if IS_ENABLED(CONFIG_IPV6)
10870 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10871 					  skc_v6_daddr.s6_addr32[0]) != 4);
10872 
10873 		off = si->off;
10874 		off -= offsetof(struct sk_msg_md, remote_ip6[0]);
10875 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10876 						struct sk_msg, sk),
10877 				      si->dst_reg, si->src_reg,
10878 				      offsetof(struct sk_msg, sk));
10879 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10880 				      offsetof(struct sock_common,
10881 					       skc_v6_daddr.s6_addr32[0]) +
10882 				      off);
10883 #else
10884 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10885 #endif
10886 		break;
10887 
10888 	case offsetof(struct sk_msg_md, local_ip6[0]) ...
10889 	     offsetof(struct sk_msg_md, local_ip6[3]):
10890 #if IS_ENABLED(CONFIG_IPV6)
10891 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10892 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10893 
10894 		off = si->off;
10895 		off -= offsetof(struct sk_msg_md, local_ip6[0]);
10896 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10897 						struct sk_msg, sk),
10898 				      si->dst_reg, si->src_reg,
10899 				      offsetof(struct sk_msg, sk));
10900 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10901 				      offsetof(struct sock_common,
10902 					       skc_v6_rcv_saddr.s6_addr32[0]) +
10903 				      off);
10904 #else
10905 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10906 #endif
10907 		break;
10908 
10909 	case offsetof(struct sk_msg_md, remote_port):
10910 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10911 
10912 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10913 						struct sk_msg, sk),
10914 				      si->dst_reg, si->src_reg,
10915 				      offsetof(struct sk_msg, sk));
10916 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10917 				      offsetof(struct sock_common, skc_dport));
10918 #ifndef __BIG_ENDIAN_BITFIELD
10919 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10920 #endif
10921 		break;
10922 
10923 	case offsetof(struct sk_msg_md, local_port):
10924 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10925 
10926 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10927 						struct sk_msg, sk),
10928 				      si->dst_reg, si->src_reg,
10929 				      offsetof(struct sk_msg, sk));
10930 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10931 				      offsetof(struct sock_common, skc_num));
10932 		break;
10933 
10934 	case offsetof(struct sk_msg_md, size):
10935 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
10936 				      si->dst_reg, si->src_reg,
10937 				      offsetof(struct sk_msg_sg, size));
10938 		break;
10939 
10940 	case offsetof(struct sk_msg_md, sk):
10941 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, sk),
10942 				      si->dst_reg, si->src_reg,
10943 				      offsetof(struct sk_msg, sk));
10944 		break;
10945 	}
10946 
10947 	return insn - insn_buf;
10948 }
10949 
10950 const struct bpf_verifier_ops sk_filter_verifier_ops = {
10951 	.get_func_proto		= sk_filter_func_proto,
10952 	.is_valid_access	= sk_filter_is_valid_access,
10953 	.convert_ctx_access	= bpf_convert_ctx_access,
10954 	.gen_ld_abs		= bpf_gen_ld_abs,
10955 };
10956 
10957 const struct bpf_prog_ops sk_filter_prog_ops = {
10958 	.test_run		= bpf_prog_test_run_skb,
10959 };
10960 
10961 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
10962 	.get_func_proto		= tc_cls_act_func_proto,
10963 	.is_valid_access	= tc_cls_act_is_valid_access,
10964 	.convert_ctx_access	= tc_cls_act_convert_ctx_access,
10965 	.gen_prologue		= tc_cls_act_prologue,
10966 	.gen_ld_abs		= bpf_gen_ld_abs,
10967 	.btf_struct_access	= tc_cls_act_btf_struct_access,
10968 };
10969 
10970 const struct bpf_prog_ops tc_cls_act_prog_ops = {
10971 	.test_run		= bpf_prog_test_run_skb,
10972 };
10973 
10974 const struct bpf_verifier_ops xdp_verifier_ops = {
10975 	.get_func_proto		= xdp_func_proto,
10976 	.is_valid_access	= xdp_is_valid_access,
10977 	.convert_ctx_access	= xdp_convert_ctx_access,
10978 	.gen_prologue		= bpf_noop_prologue,
10979 	.btf_struct_access	= xdp_btf_struct_access,
10980 };
10981 
10982 const struct bpf_prog_ops xdp_prog_ops = {
10983 	.test_run		= bpf_prog_test_run_xdp,
10984 };
10985 
10986 const struct bpf_verifier_ops cg_skb_verifier_ops = {
10987 	.get_func_proto		= cg_skb_func_proto,
10988 	.is_valid_access	= cg_skb_is_valid_access,
10989 	.convert_ctx_access	= bpf_convert_ctx_access,
10990 };
10991 
10992 const struct bpf_prog_ops cg_skb_prog_ops = {
10993 	.test_run		= bpf_prog_test_run_skb,
10994 };
10995 
10996 const struct bpf_verifier_ops lwt_in_verifier_ops = {
10997 	.get_func_proto		= lwt_in_func_proto,
10998 	.is_valid_access	= lwt_is_valid_access,
10999 	.convert_ctx_access	= bpf_convert_ctx_access,
11000 };
11001 
11002 const struct bpf_prog_ops lwt_in_prog_ops = {
11003 	.test_run		= bpf_prog_test_run_skb,
11004 };
11005 
11006 const struct bpf_verifier_ops lwt_out_verifier_ops = {
11007 	.get_func_proto		= lwt_out_func_proto,
11008 	.is_valid_access	= lwt_is_valid_access,
11009 	.convert_ctx_access	= bpf_convert_ctx_access,
11010 };
11011 
11012 const struct bpf_prog_ops lwt_out_prog_ops = {
11013 	.test_run		= bpf_prog_test_run_skb,
11014 };
11015 
11016 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
11017 	.get_func_proto		= lwt_xmit_func_proto,
11018 	.is_valid_access	= lwt_is_valid_access,
11019 	.convert_ctx_access	= bpf_convert_ctx_access,
11020 	.gen_prologue		= tc_cls_act_prologue,
11021 };
11022 
11023 const struct bpf_prog_ops lwt_xmit_prog_ops = {
11024 	.test_run		= bpf_prog_test_run_skb,
11025 };
11026 
11027 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
11028 	.get_func_proto		= lwt_seg6local_func_proto,
11029 	.is_valid_access	= lwt_is_valid_access,
11030 	.convert_ctx_access	= bpf_convert_ctx_access,
11031 };
11032 
11033 const struct bpf_prog_ops lwt_seg6local_prog_ops = {
11034 	.test_run		= bpf_prog_test_run_skb,
11035 };
11036 
11037 const struct bpf_verifier_ops cg_sock_verifier_ops = {
11038 	.get_func_proto		= sock_filter_func_proto,
11039 	.is_valid_access	= sock_filter_is_valid_access,
11040 	.convert_ctx_access	= bpf_sock_convert_ctx_access,
11041 };
11042 
11043 const struct bpf_prog_ops cg_sock_prog_ops = {
11044 };
11045 
11046 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
11047 	.get_func_proto		= sock_addr_func_proto,
11048 	.is_valid_access	= sock_addr_is_valid_access,
11049 	.convert_ctx_access	= sock_addr_convert_ctx_access,
11050 };
11051 
11052 const struct bpf_prog_ops cg_sock_addr_prog_ops = {
11053 };
11054 
11055 const struct bpf_verifier_ops sock_ops_verifier_ops = {
11056 	.get_func_proto		= sock_ops_func_proto,
11057 	.is_valid_access	= sock_ops_is_valid_access,
11058 	.convert_ctx_access	= sock_ops_convert_ctx_access,
11059 };
11060 
11061 const struct bpf_prog_ops sock_ops_prog_ops = {
11062 };
11063 
11064 const struct bpf_verifier_ops sk_skb_verifier_ops = {
11065 	.get_func_proto		= sk_skb_func_proto,
11066 	.is_valid_access	= sk_skb_is_valid_access,
11067 	.convert_ctx_access	= sk_skb_convert_ctx_access,
11068 	.gen_prologue		= sk_skb_prologue,
11069 };
11070 
11071 const struct bpf_prog_ops sk_skb_prog_ops = {
11072 };
11073 
11074 const struct bpf_verifier_ops sk_msg_verifier_ops = {
11075 	.get_func_proto		= sk_msg_func_proto,
11076 	.is_valid_access	= sk_msg_is_valid_access,
11077 	.convert_ctx_access	= sk_msg_convert_ctx_access,
11078 	.gen_prologue		= bpf_noop_prologue,
11079 };
11080 
11081 const struct bpf_prog_ops sk_msg_prog_ops = {
11082 };
11083 
11084 const struct bpf_verifier_ops flow_dissector_verifier_ops = {
11085 	.get_func_proto		= flow_dissector_func_proto,
11086 	.is_valid_access	= flow_dissector_is_valid_access,
11087 	.convert_ctx_access	= flow_dissector_convert_ctx_access,
11088 };
11089 
11090 const struct bpf_prog_ops flow_dissector_prog_ops = {
11091 	.test_run		= bpf_prog_test_run_flow_dissector,
11092 };
11093 
sk_detach_filter(struct sock * sk)11094 int sk_detach_filter(struct sock *sk)
11095 {
11096 	int ret = -ENOENT;
11097 	struct sk_filter *filter;
11098 
11099 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
11100 		return -EPERM;
11101 
11102 	filter = rcu_dereference_protected(sk->sk_filter,
11103 					   lockdep_sock_is_held(sk));
11104 	if (filter) {
11105 		RCU_INIT_POINTER(sk->sk_filter, NULL);
11106 		sk_filter_uncharge(sk, filter);
11107 		ret = 0;
11108 	}
11109 
11110 	return ret;
11111 }
11112 EXPORT_SYMBOL_GPL(sk_detach_filter);
11113 
sk_get_filter(struct sock * sk,sockptr_t optval,unsigned int len)11114 int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len)
11115 {
11116 	struct sock_fprog_kern *fprog;
11117 	struct sk_filter *filter;
11118 	int ret = 0;
11119 
11120 	sockopt_lock_sock(sk);
11121 	filter = rcu_dereference_protected(sk->sk_filter,
11122 					   lockdep_sock_is_held(sk));
11123 	if (!filter)
11124 		goto out;
11125 
11126 	/* We're copying the filter that has been originally attached,
11127 	 * so no conversion/decode needed anymore. eBPF programs that
11128 	 * have no original program cannot be dumped through this.
11129 	 */
11130 	ret = -EACCES;
11131 	fprog = filter->prog->orig_prog;
11132 	if (!fprog)
11133 		goto out;
11134 
11135 	ret = fprog->len;
11136 	if (!len)
11137 		/* User space only enquires number of filter blocks. */
11138 		goto out;
11139 
11140 	ret = -EINVAL;
11141 	if (len < fprog->len)
11142 		goto out;
11143 
11144 	ret = -EFAULT;
11145 	if (copy_to_sockptr(optval, fprog->filter, bpf_classic_proglen(fprog)))
11146 		goto out;
11147 
11148 	/* Instead of bytes, the API requests to return the number
11149 	 * of filter blocks.
11150 	 */
11151 	ret = fprog->len;
11152 out:
11153 	sockopt_release_sock(sk);
11154 	return ret;
11155 }
11156 
11157 #ifdef CONFIG_INET
bpf_init_reuseport_kern(struct sk_reuseport_kern * reuse_kern,struct sock_reuseport * reuse,struct sock * sk,struct sk_buff * skb,struct sock * migrating_sk,u32 hash)11158 static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
11159 				    struct sock_reuseport *reuse,
11160 				    struct sock *sk, struct sk_buff *skb,
11161 				    struct sock *migrating_sk,
11162 				    u32 hash)
11163 {
11164 	reuse_kern->skb = skb;
11165 	reuse_kern->sk = sk;
11166 	reuse_kern->selected_sk = NULL;
11167 	reuse_kern->migrating_sk = migrating_sk;
11168 	reuse_kern->data_end = skb->data + skb_headlen(skb);
11169 	reuse_kern->hash = hash;
11170 	reuse_kern->reuseport_id = reuse->reuseport_id;
11171 	reuse_kern->bind_inany = reuse->bind_inany;
11172 }
11173 
bpf_run_sk_reuseport(struct sock_reuseport * reuse,struct sock * sk,struct bpf_prog * prog,struct sk_buff * skb,struct sock * migrating_sk,u32 hash)11174 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
11175 				  struct bpf_prog *prog, struct sk_buff *skb,
11176 				  struct sock *migrating_sk,
11177 				  u32 hash)
11178 {
11179 	struct sk_reuseport_kern reuse_kern;
11180 	enum sk_action action;
11181 
11182 	bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, migrating_sk, hash);
11183 	action = bpf_prog_run(prog, &reuse_kern);
11184 
11185 	if (action == SK_PASS)
11186 		return reuse_kern.selected_sk;
11187 	else
11188 		return ERR_PTR(-ECONNREFUSED);
11189 }
11190 
BPF_CALL_4(sk_select_reuseport,struct sk_reuseport_kern *,reuse_kern,struct bpf_map *,map,void *,key,u32,flags)11191 BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
11192 	   struct bpf_map *, map, void *, key, u32, flags)
11193 {
11194 	bool is_sockarray = map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY;
11195 	struct sock_reuseport *reuse;
11196 	struct sock *selected_sk;
11197 	int err;
11198 
11199 	selected_sk = map->ops->map_lookup_elem(map, key);
11200 	if (!selected_sk)
11201 		return -ENOENT;
11202 
11203 	reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
11204 	if (!reuse) {
11205 		/* reuseport_array has only sk with non NULL sk_reuseport_cb.
11206 		 * The only (!reuse) case here is - the sk has already been
11207 		 * unhashed (e.g. by close()), so treat it as -ENOENT.
11208 		 *
11209 		 * Other maps (e.g. sock_map) do not provide this guarantee and
11210 		 * the sk may never be in the reuseport group to begin with.
11211 		 */
11212 		err = is_sockarray ? -ENOENT : -EINVAL;
11213 		goto error;
11214 	}
11215 
11216 	if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
11217 		struct sock *sk = reuse_kern->sk;
11218 
11219 		if (sk->sk_protocol != selected_sk->sk_protocol) {
11220 			err = -EPROTOTYPE;
11221 		} else if (sk->sk_family != selected_sk->sk_family) {
11222 			err = -EAFNOSUPPORT;
11223 		} else {
11224 			/* Catch all. Likely bound to a different sockaddr. */
11225 			err = -EBADFD;
11226 		}
11227 		goto error;
11228 	}
11229 
11230 	reuse_kern->selected_sk = selected_sk;
11231 
11232 	return 0;
11233 error:
11234 	/* Lookup in sock_map can return TCP ESTABLISHED sockets. */
11235 	if (sk_is_refcounted(selected_sk))
11236 		sock_put(selected_sk);
11237 
11238 	return err;
11239 }
11240 
11241 static const struct bpf_func_proto sk_select_reuseport_proto = {
11242 	.func           = sk_select_reuseport,
11243 	.gpl_only       = false,
11244 	.ret_type       = RET_INTEGER,
11245 	.arg1_type	= ARG_PTR_TO_CTX,
11246 	.arg2_type      = ARG_CONST_MAP_PTR,
11247 	.arg3_type      = ARG_PTR_TO_MAP_KEY,
11248 	.arg4_type	= ARG_ANYTHING,
11249 };
11250 
BPF_CALL_4(sk_reuseport_load_bytes,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len)11251 BPF_CALL_4(sk_reuseport_load_bytes,
11252 	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
11253 	   void *, to, u32, len)
11254 {
11255 	return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
11256 }
11257 
11258 static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
11259 	.func		= sk_reuseport_load_bytes,
11260 	.gpl_only	= false,
11261 	.ret_type	= RET_INTEGER,
11262 	.arg1_type	= ARG_PTR_TO_CTX,
11263 	.arg2_type	= ARG_ANYTHING,
11264 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
11265 	.arg4_type	= ARG_CONST_SIZE,
11266 };
11267 
BPF_CALL_5(sk_reuseport_load_bytes_relative,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len,u32,start_header)11268 BPF_CALL_5(sk_reuseport_load_bytes_relative,
11269 	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
11270 	   void *, to, u32, len, u32, start_header)
11271 {
11272 	return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
11273 					       len, start_header);
11274 }
11275 
11276 static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
11277 	.func		= sk_reuseport_load_bytes_relative,
11278 	.gpl_only	= false,
11279 	.ret_type	= RET_INTEGER,
11280 	.arg1_type	= ARG_PTR_TO_CTX,
11281 	.arg2_type	= ARG_ANYTHING,
11282 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
11283 	.arg4_type	= ARG_CONST_SIZE,
11284 	.arg5_type	= ARG_ANYTHING,
11285 };
11286 
11287 static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)11288 sk_reuseport_func_proto(enum bpf_func_id func_id,
11289 			const struct bpf_prog *prog)
11290 {
11291 	switch (func_id) {
11292 	case BPF_FUNC_sk_select_reuseport:
11293 		return &sk_select_reuseport_proto;
11294 	case BPF_FUNC_skb_load_bytes:
11295 		return &sk_reuseport_load_bytes_proto;
11296 	case BPF_FUNC_skb_load_bytes_relative:
11297 		return &sk_reuseport_load_bytes_relative_proto;
11298 	case BPF_FUNC_get_socket_cookie:
11299 		return &bpf_get_socket_ptr_cookie_proto;
11300 	case BPF_FUNC_ktime_get_coarse_ns:
11301 		return &bpf_ktime_get_coarse_ns_proto;
11302 	default:
11303 		return bpf_base_func_proto(func_id);
11304 	}
11305 }
11306 
11307 static bool
sk_reuseport_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)11308 sk_reuseport_is_valid_access(int off, int size,
11309 			     enum bpf_access_type type,
11310 			     const struct bpf_prog *prog,
11311 			     struct bpf_insn_access_aux *info)
11312 {
11313 	const u32 size_default = sizeof(__u32);
11314 
11315 	if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
11316 	    off % size || type != BPF_READ)
11317 		return false;
11318 
11319 	switch (off) {
11320 	case offsetof(struct sk_reuseport_md, data):
11321 		info->reg_type = PTR_TO_PACKET;
11322 		return size == sizeof(__u64);
11323 
11324 	case offsetof(struct sk_reuseport_md, data_end):
11325 		info->reg_type = PTR_TO_PACKET_END;
11326 		return size == sizeof(__u64);
11327 
11328 	case offsetof(struct sk_reuseport_md, hash):
11329 		return size == size_default;
11330 
11331 	case offsetof(struct sk_reuseport_md, sk):
11332 		info->reg_type = PTR_TO_SOCKET;
11333 		return size == sizeof(__u64);
11334 
11335 	case offsetof(struct sk_reuseport_md, migrating_sk):
11336 		info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
11337 		return size == sizeof(__u64);
11338 
11339 	/* Fields that allow narrowing */
11340 	case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
11341 		if (size < sizeof_field(struct sk_buff, protocol))
11342 			return false;
11343 		fallthrough;
11344 	case bpf_ctx_range(struct sk_reuseport_md, ip_protocol):
11345 	case bpf_ctx_range(struct sk_reuseport_md, bind_inany):
11346 	case bpf_ctx_range(struct sk_reuseport_md, len):
11347 		bpf_ctx_record_field_size(info, size_default);
11348 		return bpf_ctx_narrow_access_ok(off, size, size_default);
11349 
11350 	default:
11351 		return false;
11352 	}
11353 }
11354 
11355 #define SK_REUSEPORT_LOAD_FIELD(F) ({					\
11356 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
11357 			      si->dst_reg, si->src_reg,			\
11358 			      bpf_target_off(struct sk_reuseport_kern, F, \
11359 					     sizeof_field(struct sk_reuseport_kern, F), \
11360 					     target_size));		\
11361 	})
11362 
11363 #define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD)				\
11364 	SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,		\
11365 				    struct sk_buff,			\
11366 				    skb,				\
11367 				    SKB_FIELD)
11368 
11369 #define SK_REUSEPORT_LOAD_SK_FIELD(SK_FIELD)				\
11370 	SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,		\
11371 				    struct sock,			\
11372 				    sk,					\
11373 				    SK_FIELD)
11374 
sk_reuseport_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)11375 static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
11376 					   const struct bpf_insn *si,
11377 					   struct bpf_insn *insn_buf,
11378 					   struct bpf_prog *prog,
11379 					   u32 *target_size)
11380 {
11381 	struct bpf_insn *insn = insn_buf;
11382 
11383 	switch (si->off) {
11384 	case offsetof(struct sk_reuseport_md, data):
11385 		SK_REUSEPORT_LOAD_SKB_FIELD(data);
11386 		break;
11387 
11388 	case offsetof(struct sk_reuseport_md, len):
11389 		SK_REUSEPORT_LOAD_SKB_FIELD(len);
11390 		break;
11391 
11392 	case offsetof(struct sk_reuseport_md, eth_protocol):
11393 		SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
11394 		break;
11395 
11396 	case offsetof(struct sk_reuseport_md, ip_protocol):
11397 		SK_REUSEPORT_LOAD_SK_FIELD(sk_protocol);
11398 		break;
11399 
11400 	case offsetof(struct sk_reuseport_md, data_end):
11401 		SK_REUSEPORT_LOAD_FIELD(data_end);
11402 		break;
11403 
11404 	case offsetof(struct sk_reuseport_md, hash):
11405 		SK_REUSEPORT_LOAD_FIELD(hash);
11406 		break;
11407 
11408 	case offsetof(struct sk_reuseport_md, bind_inany):
11409 		SK_REUSEPORT_LOAD_FIELD(bind_inany);
11410 		break;
11411 
11412 	case offsetof(struct sk_reuseport_md, sk):
11413 		SK_REUSEPORT_LOAD_FIELD(sk);
11414 		break;
11415 
11416 	case offsetof(struct sk_reuseport_md, migrating_sk):
11417 		SK_REUSEPORT_LOAD_FIELD(migrating_sk);
11418 		break;
11419 	}
11420 
11421 	return insn - insn_buf;
11422 }
11423 
11424 const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
11425 	.get_func_proto		= sk_reuseport_func_proto,
11426 	.is_valid_access	= sk_reuseport_is_valid_access,
11427 	.convert_ctx_access	= sk_reuseport_convert_ctx_access,
11428 };
11429 
11430 const struct bpf_prog_ops sk_reuseport_prog_ops = {
11431 };
11432 
11433 DEFINE_STATIC_KEY_FALSE(bpf_sk_lookup_enabled);
11434 EXPORT_SYMBOL(bpf_sk_lookup_enabled);
11435 
BPF_CALL_3(bpf_sk_lookup_assign,struct bpf_sk_lookup_kern *,ctx,struct sock *,sk,u64,flags)11436 BPF_CALL_3(bpf_sk_lookup_assign, struct bpf_sk_lookup_kern *, ctx,
11437 	   struct sock *, sk, u64, flags)
11438 {
11439 	if (unlikely(flags & ~(BPF_SK_LOOKUP_F_REPLACE |
11440 			       BPF_SK_LOOKUP_F_NO_REUSEPORT)))
11441 		return -EINVAL;
11442 	if (unlikely(sk && sk_is_refcounted(sk)))
11443 		return -ESOCKTNOSUPPORT; /* reject non-RCU freed sockets */
11444 	if (unlikely(sk && sk_is_tcp(sk) && sk->sk_state != TCP_LISTEN))
11445 		return -ESOCKTNOSUPPORT; /* only accept TCP socket in LISTEN */
11446 	if (unlikely(sk && sk_is_udp(sk) && sk->sk_state != TCP_CLOSE))
11447 		return -ESOCKTNOSUPPORT; /* only accept UDP socket in CLOSE */
11448 
11449 	/* Check if socket is suitable for packet L3/L4 protocol */
11450 	if (sk && sk->sk_protocol != ctx->protocol)
11451 		return -EPROTOTYPE;
11452 	if (sk && sk->sk_family != ctx->family &&
11453 	    (sk->sk_family == AF_INET || ipv6_only_sock(sk)))
11454 		return -EAFNOSUPPORT;
11455 
11456 	if (ctx->selected_sk && !(flags & BPF_SK_LOOKUP_F_REPLACE))
11457 		return -EEXIST;
11458 
11459 	/* Select socket as lookup result */
11460 	ctx->selected_sk = sk;
11461 	ctx->no_reuseport = flags & BPF_SK_LOOKUP_F_NO_REUSEPORT;
11462 	return 0;
11463 }
11464 
11465 static const struct bpf_func_proto bpf_sk_lookup_assign_proto = {
11466 	.func		= bpf_sk_lookup_assign,
11467 	.gpl_only	= false,
11468 	.ret_type	= RET_INTEGER,
11469 	.arg1_type	= ARG_PTR_TO_CTX,
11470 	.arg2_type	= ARG_PTR_TO_SOCKET_OR_NULL,
11471 	.arg3_type	= ARG_ANYTHING,
11472 };
11473 
11474 static const struct bpf_func_proto *
sk_lookup_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)11475 sk_lookup_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
11476 {
11477 	switch (func_id) {
11478 	case BPF_FUNC_perf_event_output:
11479 		return &bpf_event_output_data_proto;
11480 	case BPF_FUNC_sk_assign:
11481 		return &bpf_sk_lookup_assign_proto;
11482 	case BPF_FUNC_sk_release:
11483 		return &bpf_sk_release_proto;
11484 	default:
11485 		return bpf_sk_base_func_proto(func_id);
11486 	}
11487 }
11488 
sk_lookup_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)11489 static bool sk_lookup_is_valid_access(int off, int size,
11490 				      enum bpf_access_type type,
11491 				      const struct bpf_prog *prog,
11492 				      struct bpf_insn_access_aux *info)
11493 {
11494 	if (off < 0 || off >= sizeof(struct bpf_sk_lookup))
11495 		return false;
11496 	if (off % size != 0)
11497 		return false;
11498 	if (type != BPF_READ)
11499 		return false;
11500 
11501 	switch (off) {
11502 	case offsetof(struct bpf_sk_lookup, sk):
11503 		info->reg_type = PTR_TO_SOCKET_OR_NULL;
11504 		return size == sizeof(__u64);
11505 
11506 	case bpf_ctx_range(struct bpf_sk_lookup, family):
11507 	case bpf_ctx_range(struct bpf_sk_lookup, protocol):
11508 	case bpf_ctx_range(struct bpf_sk_lookup, remote_ip4):
11509 	case bpf_ctx_range(struct bpf_sk_lookup, local_ip4):
11510 	case bpf_ctx_range_till(struct bpf_sk_lookup, remote_ip6[0], remote_ip6[3]):
11511 	case bpf_ctx_range_till(struct bpf_sk_lookup, local_ip6[0], local_ip6[3]):
11512 	case bpf_ctx_range(struct bpf_sk_lookup, local_port):
11513 	case bpf_ctx_range(struct bpf_sk_lookup, ingress_ifindex):
11514 		bpf_ctx_record_field_size(info, sizeof(__u32));
11515 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__u32));
11516 
11517 	case bpf_ctx_range(struct bpf_sk_lookup, remote_port):
11518 		/* Allow 4-byte access to 2-byte field for backward compatibility */
11519 		if (size == sizeof(__u32))
11520 			return true;
11521 		bpf_ctx_record_field_size(info, sizeof(__be16));
11522 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__be16));
11523 
11524 	case offsetofend(struct bpf_sk_lookup, remote_port) ...
11525 	     offsetof(struct bpf_sk_lookup, local_ip4) - 1:
11526 		/* Allow access to zero padding for backward compatibility */
11527 		bpf_ctx_record_field_size(info, sizeof(__u16));
11528 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__u16));
11529 
11530 	default:
11531 		return false;
11532 	}
11533 }
11534 
sk_lookup_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)11535 static u32 sk_lookup_convert_ctx_access(enum bpf_access_type type,
11536 					const struct bpf_insn *si,
11537 					struct bpf_insn *insn_buf,
11538 					struct bpf_prog *prog,
11539 					u32 *target_size)
11540 {
11541 	struct bpf_insn *insn = insn_buf;
11542 
11543 	switch (si->off) {
11544 	case offsetof(struct bpf_sk_lookup, sk):
11545 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11546 				      offsetof(struct bpf_sk_lookup_kern, selected_sk));
11547 		break;
11548 
11549 	case offsetof(struct bpf_sk_lookup, family):
11550 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11551 				      bpf_target_off(struct bpf_sk_lookup_kern,
11552 						     family, 2, target_size));
11553 		break;
11554 
11555 	case offsetof(struct bpf_sk_lookup, protocol):
11556 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11557 				      bpf_target_off(struct bpf_sk_lookup_kern,
11558 						     protocol, 2, target_size));
11559 		break;
11560 
11561 	case offsetof(struct bpf_sk_lookup, remote_ip4):
11562 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11563 				      bpf_target_off(struct bpf_sk_lookup_kern,
11564 						     v4.saddr, 4, target_size));
11565 		break;
11566 
11567 	case offsetof(struct bpf_sk_lookup, local_ip4):
11568 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11569 				      bpf_target_off(struct bpf_sk_lookup_kern,
11570 						     v4.daddr, 4, target_size));
11571 		break;
11572 
11573 	case bpf_ctx_range_till(struct bpf_sk_lookup,
11574 				remote_ip6[0], remote_ip6[3]): {
11575 #if IS_ENABLED(CONFIG_IPV6)
11576 		int off = si->off;
11577 
11578 		off -= offsetof(struct bpf_sk_lookup, remote_ip6[0]);
11579 		off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11580 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11581 				      offsetof(struct bpf_sk_lookup_kern, v6.saddr));
11582 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11583 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11584 #else
11585 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11586 #endif
11587 		break;
11588 	}
11589 	case bpf_ctx_range_till(struct bpf_sk_lookup,
11590 				local_ip6[0], local_ip6[3]): {
11591 #if IS_ENABLED(CONFIG_IPV6)
11592 		int off = si->off;
11593 
11594 		off -= offsetof(struct bpf_sk_lookup, local_ip6[0]);
11595 		off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11596 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11597 				      offsetof(struct bpf_sk_lookup_kern, v6.daddr));
11598 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11599 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11600 #else
11601 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11602 #endif
11603 		break;
11604 	}
11605 	case offsetof(struct bpf_sk_lookup, remote_port):
11606 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11607 				      bpf_target_off(struct bpf_sk_lookup_kern,
11608 						     sport, 2, target_size));
11609 		break;
11610 
11611 	case offsetofend(struct bpf_sk_lookup, remote_port):
11612 		*target_size = 2;
11613 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11614 		break;
11615 
11616 	case offsetof(struct bpf_sk_lookup, local_port):
11617 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11618 				      bpf_target_off(struct bpf_sk_lookup_kern,
11619 						     dport, 2, target_size));
11620 		break;
11621 
11622 	case offsetof(struct bpf_sk_lookup, ingress_ifindex):
11623 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11624 				      bpf_target_off(struct bpf_sk_lookup_kern,
11625 						     ingress_ifindex, 4, target_size));
11626 		break;
11627 	}
11628 
11629 	return insn - insn_buf;
11630 }
11631 
11632 const struct bpf_prog_ops sk_lookup_prog_ops = {
11633 	.test_run = bpf_prog_test_run_sk_lookup,
11634 };
11635 
11636 const struct bpf_verifier_ops sk_lookup_verifier_ops = {
11637 	.get_func_proto		= sk_lookup_func_proto,
11638 	.is_valid_access	= sk_lookup_is_valid_access,
11639 	.convert_ctx_access	= sk_lookup_convert_ctx_access,
11640 };
11641 
11642 #endif /* CONFIG_INET */
11643 
DEFINE_BPF_DISPATCHER(xdp)11644 DEFINE_BPF_DISPATCHER(xdp)
11645 
11646 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog)
11647 {
11648 	bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(xdp), prev_prog, prog);
11649 }
11650 
BTF_ID_LIST_GLOBAL(btf_sock_ids,MAX_BTF_SOCK_TYPE)11651 BTF_ID_LIST_GLOBAL(btf_sock_ids, MAX_BTF_SOCK_TYPE)
11652 #define BTF_SOCK_TYPE(name, type) BTF_ID(struct, type)
11653 BTF_SOCK_TYPE_xxx
11654 #undef BTF_SOCK_TYPE
11655 
11656 BPF_CALL_1(bpf_skc_to_tcp6_sock, struct sock *, sk)
11657 {
11658 	/* tcp6_sock type is not generated in dwarf and hence btf,
11659 	 * trigger an explicit type generation here.
11660 	 */
11661 	BTF_TYPE_EMIT(struct tcp6_sock);
11662 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP &&
11663 	    sk->sk_family == AF_INET6)
11664 		return (unsigned long)sk;
11665 
11666 	return (unsigned long)NULL;
11667 }
11668 
11669 const struct bpf_func_proto bpf_skc_to_tcp6_sock_proto = {
11670 	.func			= bpf_skc_to_tcp6_sock,
11671 	.gpl_only		= false,
11672 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11673 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11674 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP6],
11675 };
11676 
BPF_CALL_1(bpf_skc_to_tcp_sock,struct sock *,sk)11677 BPF_CALL_1(bpf_skc_to_tcp_sock, struct sock *, sk)
11678 {
11679 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
11680 		return (unsigned long)sk;
11681 
11682 	return (unsigned long)NULL;
11683 }
11684 
11685 const struct bpf_func_proto bpf_skc_to_tcp_sock_proto = {
11686 	.func			= bpf_skc_to_tcp_sock,
11687 	.gpl_only		= false,
11688 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11689 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11690 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP],
11691 };
11692 
BPF_CALL_1(bpf_skc_to_tcp_timewait_sock,struct sock *,sk)11693 BPF_CALL_1(bpf_skc_to_tcp_timewait_sock, struct sock *, sk)
11694 {
11695 	/* BTF types for tcp_timewait_sock and inet_timewait_sock are not
11696 	 * generated if CONFIG_INET=n. Trigger an explicit generation here.
11697 	 */
11698 	BTF_TYPE_EMIT(struct inet_timewait_sock);
11699 	BTF_TYPE_EMIT(struct tcp_timewait_sock);
11700 
11701 #ifdef CONFIG_INET
11702 	if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_TIME_WAIT)
11703 		return (unsigned long)sk;
11704 #endif
11705 
11706 #if IS_BUILTIN(CONFIG_IPV6)
11707 	if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_TIME_WAIT)
11708 		return (unsigned long)sk;
11709 #endif
11710 
11711 	return (unsigned long)NULL;
11712 }
11713 
11714 const struct bpf_func_proto bpf_skc_to_tcp_timewait_sock_proto = {
11715 	.func			= bpf_skc_to_tcp_timewait_sock,
11716 	.gpl_only		= false,
11717 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11718 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11719 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP_TW],
11720 };
11721 
BPF_CALL_1(bpf_skc_to_tcp_request_sock,struct sock *,sk)11722 BPF_CALL_1(bpf_skc_to_tcp_request_sock, struct sock *, sk)
11723 {
11724 #ifdef CONFIG_INET
11725 	if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11726 		return (unsigned long)sk;
11727 #endif
11728 
11729 #if IS_BUILTIN(CONFIG_IPV6)
11730 	if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11731 		return (unsigned long)sk;
11732 #endif
11733 
11734 	return (unsigned long)NULL;
11735 }
11736 
11737 const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto = {
11738 	.func			= bpf_skc_to_tcp_request_sock,
11739 	.gpl_only		= false,
11740 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11741 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11742 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP_REQ],
11743 };
11744 
BPF_CALL_1(bpf_skc_to_udp6_sock,struct sock *,sk)11745 BPF_CALL_1(bpf_skc_to_udp6_sock, struct sock *, sk)
11746 {
11747 	/* udp6_sock type is not generated in dwarf and hence btf,
11748 	 * trigger an explicit type generation here.
11749 	 */
11750 	BTF_TYPE_EMIT(struct udp6_sock);
11751 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_UDP &&
11752 	    sk->sk_type == SOCK_DGRAM && sk->sk_family == AF_INET6)
11753 		return (unsigned long)sk;
11754 
11755 	return (unsigned long)NULL;
11756 }
11757 
11758 const struct bpf_func_proto bpf_skc_to_udp6_sock_proto = {
11759 	.func			= bpf_skc_to_udp6_sock,
11760 	.gpl_only		= false,
11761 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11762 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11763 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_UDP6],
11764 };
11765 
BPF_CALL_1(bpf_skc_to_unix_sock,struct sock *,sk)11766 BPF_CALL_1(bpf_skc_to_unix_sock, struct sock *, sk)
11767 {
11768 	/* unix_sock type is not generated in dwarf and hence btf,
11769 	 * trigger an explicit type generation here.
11770 	 */
11771 	BTF_TYPE_EMIT(struct unix_sock);
11772 	if (sk && sk_fullsock(sk) && sk->sk_family == AF_UNIX)
11773 		return (unsigned long)sk;
11774 
11775 	return (unsigned long)NULL;
11776 }
11777 
11778 const struct bpf_func_proto bpf_skc_to_unix_sock_proto = {
11779 	.func			= bpf_skc_to_unix_sock,
11780 	.gpl_only		= false,
11781 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11782 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11783 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_UNIX],
11784 };
11785 
BPF_CALL_1(bpf_skc_to_mptcp_sock,struct sock *,sk)11786 BPF_CALL_1(bpf_skc_to_mptcp_sock, struct sock *, sk)
11787 {
11788 	BTF_TYPE_EMIT(struct mptcp_sock);
11789 	return (unsigned long)bpf_mptcp_sock_from_subflow(sk);
11790 }
11791 
11792 const struct bpf_func_proto bpf_skc_to_mptcp_sock_proto = {
11793 	.func		= bpf_skc_to_mptcp_sock,
11794 	.gpl_only	= false,
11795 	.ret_type	= RET_PTR_TO_BTF_ID_OR_NULL,
11796 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
11797 	.ret_btf_id	= &btf_sock_ids[BTF_SOCK_TYPE_MPTCP],
11798 };
11799 
BPF_CALL_1(bpf_sock_from_file,struct file *,file)11800 BPF_CALL_1(bpf_sock_from_file, struct file *, file)
11801 {
11802 	return (unsigned long)sock_from_file(file);
11803 }
11804 
11805 BTF_ID_LIST(bpf_sock_from_file_btf_ids)
11806 BTF_ID(struct, socket)
11807 BTF_ID(struct, file)
11808 
11809 const struct bpf_func_proto bpf_sock_from_file_proto = {
11810 	.func		= bpf_sock_from_file,
11811 	.gpl_only	= false,
11812 	.ret_type	= RET_PTR_TO_BTF_ID_OR_NULL,
11813 	.ret_btf_id	= &bpf_sock_from_file_btf_ids[0],
11814 	.arg1_type	= ARG_PTR_TO_BTF_ID,
11815 	.arg1_btf_id	= &bpf_sock_from_file_btf_ids[1],
11816 };
11817 
11818 static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id)11819 bpf_sk_base_func_proto(enum bpf_func_id func_id)
11820 {
11821 	const struct bpf_func_proto *func;
11822 
11823 	switch (func_id) {
11824 	case BPF_FUNC_skc_to_tcp6_sock:
11825 		func = &bpf_skc_to_tcp6_sock_proto;
11826 		break;
11827 	case BPF_FUNC_skc_to_tcp_sock:
11828 		func = &bpf_skc_to_tcp_sock_proto;
11829 		break;
11830 	case BPF_FUNC_skc_to_tcp_timewait_sock:
11831 		func = &bpf_skc_to_tcp_timewait_sock_proto;
11832 		break;
11833 	case BPF_FUNC_skc_to_tcp_request_sock:
11834 		func = &bpf_skc_to_tcp_request_sock_proto;
11835 		break;
11836 	case BPF_FUNC_skc_to_udp6_sock:
11837 		func = &bpf_skc_to_udp6_sock_proto;
11838 		break;
11839 	case BPF_FUNC_skc_to_unix_sock:
11840 		func = &bpf_skc_to_unix_sock_proto;
11841 		break;
11842 	case BPF_FUNC_skc_to_mptcp_sock:
11843 		func = &bpf_skc_to_mptcp_sock_proto;
11844 		break;
11845 	case BPF_FUNC_ktime_get_coarse_ns:
11846 		return &bpf_ktime_get_coarse_ns_proto;
11847 	default:
11848 		return bpf_base_func_proto(func_id);
11849 	}
11850 
11851 	if (!perfmon_capable())
11852 		return NULL;
11853 
11854 	return func;
11855 }
11856 
11857 __diag_push();
11858 __diag_ignore_all("-Wmissing-prototypes",
11859 		  "Global functions as their definitions will be in vmlinux BTF");
bpf_dynptr_from_skb(struct sk_buff * skb,u64 flags,struct bpf_dynptr_kern * ptr__uninit)11860 __bpf_kfunc int bpf_dynptr_from_skb(struct sk_buff *skb, u64 flags,
11861 				    struct bpf_dynptr_kern *ptr__uninit)
11862 {
11863 	if (flags) {
11864 		bpf_dynptr_set_null(ptr__uninit);
11865 		return -EINVAL;
11866 	}
11867 
11868 	bpf_dynptr_init(ptr__uninit, skb, BPF_DYNPTR_TYPE_SKB, 0, skb->len);
11869 
11870 	return 0;
11871 }
11872 
bpf_dynptr_from_xdp(struct xdp_buff * xdp,u64 flags,struct bpf_dynptr_kern * ptr__uninit)11873 __bpf_kfunc int bpf_dynptr_from_xdp(struct xdp_buff *xdp, u64 flags,
11874 				    struct bpf_dynptr_kern *ptr__uninit)
11875 {
11876 	if (flags) {
11877 		bpf_dynptr_set_null(ptr__uninit);
11878 		return -EINVAL;
11879 	}
11880 
11881 	bpf_dynptr_init(ptr__uninit, xdp, BPF_DYNPTR_TYPE_XDP, 0, xdp_get_buff_len(xdp));
11882 
11883 	return 0;
11884 }
11885 
bpf_sock_addr_set_sun_path(struct bpf_sock_addr_kern * sa_kern,const u8 * sun_path,u32 sun_path__sz)11886 __bpf_kfunc int bpf_sock_addr_set_sun_path(struct bpf_sock_addr_kern *sa_kern,
11887 					   const u8 *sun_path, u32 sun_path__sz)
11888 {
11889 	struct sockaddr_un *un;
11890 
11891 	if (sa_kern->sk->sk_family != AF_UNIX)
11892 		return -EINVAL;
11893 
11894 	/* We do not allow changing the address to unnamed or larger than the
11895 	 * maximum allowed address size for a unix sockaddr.
11896 	 */
11897 	if (sun_path__sz == 0 || sun_path__sz > UNIX_PATH_MAX)
11898 		return -EINVAL;
11899 
11900 	un = (struct sockaddr_un *)sa_kern->uaddr;
11901 	memcpy(un->sun_path, sun_path, sun_path__sz);
11902 	sa_kern->uaddrlen = offsetof(struct sockaddr_un, sun_path) + sun_path__sz;
11903 
11904 	return 0;
11905 }
11906 __diag_pop();
11907 
bpf_dynptr_from_skb_rdonly(struct sk_buff * skb,u64 flags,struct bpf_dynptr_kern * ptr__uninit)11908 int bpf_dynptr_from_skb_rdonly(struct sk_buff *skb, u64 flags,
11909 			       struct bpf_dynptr_kern *ptr__uninit)
11910 {
11911 	int err;
11912 
11913 	err = bpf_dynptr_from_skb(skb, flags, ptr__uninit);
11914 	if (err)
11915 		return err;
11916 
11917 	bpf_dynptr_set_rdonly(ptr__uninit);
11918 
11919 	return 0;
11920 }
11921 
11922 BTF_SET8_START(bpf_kfunc_check_set_skb)
11923 BTF_ID_FLAGS(func, bpf_dynptr_from_skb)
11924 BTF_SET8_END(bpf_kfunc_check_set_skb)
11925 
11926 BTF_SET8_START(bpf_kfunc_check_set_xdp)
11927 BTF_ID_FLAGS(func, bpf_dynptr_from_xdp)
11928 BTF_SET8_END(bpf_kfunc_check_set_xdp)
11929 
11930 BTF_SET8_START(bpf_kfunc_check_set_sock_addr)
11931 BTF_ID_FLAGS(func, bpf_sock_addr_set_sun_path)
11932 BTF_SET8_END(bpf_kfunc_check_set_sock_addr)
11933 
11934 static const struct btf_kfunc_id_set bpf_kfunc_set_skb = {
11935 	.owner = THIS_MODULE,
11936 	.set = &bpf_kfunc_check_set_skb,
11937 };
11938 
11939 static const struct btf_kfunc_id_set bpf_kfunc_set_xdp = {
11940 	.owner = THIS_MODULE,
11941 	.set = &bpf_kfunc_check_set_xdp,
11942 };
11943 
11944 static const struct btf_kfunc_id_set bpf_kfunc_set_sock_addr = {
11945 	.owner = THIS_MODULE,
11946 	.set = &bpf_kfunc_check_set_sock_addr,
11947 };
11948 
bpf_kfunc_init(void)11949 static int __init bpf_kfunc_init(void)
11950 {
11951 	int ret;
11952 
11953 	ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_kfunc_set_skb);
11954 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_ACT, &bpf_kfunc_set_skb);
11955 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SK_SKB, &bpf_kfunc_set_skb);
11956 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SOCKET_FILTER, &bpf_kfunc_set_skb);
11957 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SKB, &bpf_kfunc_set_skb);
11958 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_OUT, &bpf_kfunc_set_skb);
11959 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_IN, &bpf_kfunc_set_skb);
11960 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_XMIT, &bpf_kfunc_set_skb);
11961 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_SEG6LOCAL, &bpf_kfunc_set_skb);
11962 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_NETFILTER, &bpf_kfunc_set_skb);
11963 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &bpf_kfunc_set_xdp);
11964 	return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
11965 						&bpf_kfunc_set_sock_addr);
11966 }
11967 late_initcall(bpf_kfunc_init);
11968 
11969 /* Disables missing prototype warnings */
11970 __diag_push();
11971 __diag_ignore_all("-Wmissing-prototypes",
11972 		  "Global functions as their definitions will be in vmlinux BTF");
11973 
11974 /* bpf_sock_destroy: Destroy the given socket with ECONNABORTED error code.
11975  *
11976  * The function expects a non-NULL pointer to a socket, and invokes the
11977  * protocol specific socket destroy handlers.
11978  *
11979  * The helper can only be called from BPF contexts that have acquired the socket
11980  * locks.
11981  *
11982  * Parameters:
11983  * @sock: Pointer to socket to be destroyed
11984  *
11985  * Return:
11986  * On error, may return EPROTONOSUPPORT, EINVAL.
11987  * EPROTONOSUPPORT if protocol specific destroy handler is not supported.
11988  * 0 otherwise
11989  */
bpf_sock_destroy(struct sock_common * sock)11990 __bpf_kfunc int bpf_sock_destroy(struct sock_common *sock)
11991 {
11992 	struct sock *sk = (struct sock *)sock;
11993 
11994 	/* The locking semantics that allow for synchronous execution of the
11995 	 * destroy handlers are only supported for TCP and UDP.
11996 	 * Supporting protocols will need to acquire sock lock in the BPF context
11997 	 * prior to invoking this kfunc.
11998 	 */
11999 	if (!sk->sk_prot->diag_destroy || (sk->sk_protocol != IPPROTO_TCP &&
12000 					   sk->sk_protocol != IPPROTO_UDP))
12001 		return -EOPNOTSUPP;
12002 
12003 	return sk->sk_prot->diag_destroy(sk, ECONNABORTED);
12004 }
12005 
12006 __diag_pop()
12007 
BTF_SET8_START(bpf_sk_iter_kfunc_ids)12008 BTF_SET8_START(bpf_sk_iter_kfunc_ids)
12009 BTF_ID_FLAGS(func, bpf_sock_destroy, KF_TRUSTED_ARGS)
12010 BTF_SET8_END(bpf_sk_iter_kfunc_ids)
12011 
12012 static int tracing_iter_filter(const struct bpf_prog *prog, u32 kfunc_id)
12013 {
12014 	if (btf_id_set8_contains(&bpf_sk_iter_kfunc_ids, kfunc_id) &&
12015 	    prog->expected_attach_type != BPF_TRACE_ITER)
12016 		return -EACCES;
12017 	return 0;
12018 }
12019 
12020 static const struct btf_kfunc_id_set bpf_sk_iter_kfunc_set = {
12021 	.owner = THIS_MODULE,
12022 	.set   = &bpf_sk_iter_kfunc_ids,
12023 	.filter = tracing_iter_filter,
12024 };
12025 
init_subsystem(void)12026 static int init_subsystem(void)
12027 {
12028 	return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_sk_iter_kfunc_set);
12029 }
12030 late_initcall(init_subsystem);
12031