xref: /openbmc/linux/net/core/filter.c (revision 7f964478)
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_CALL_4(bpf_skb_load_helper_8,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)214 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
215 	   data, int, headlen, int, offset)
216 {
217 	u8 tmp, *ptr;
218 	const int len = sizeof(tmp);
219 
220 	if (offset >= 0) {
221 		if (headlen - offset >= len)
222 			return *(u8 *)(data + offset);
223 		if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
224 			return tmp;
225 	} else {
226 		ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
227 		if (likely(ptr))
228 			return *(u8 *)ptr;
229 	}
230 
231 	return -EFAULT;
232 }
233 
BPF_CALL_2(bpf_skb_load_helper_8_no_cache,const struct sk_buff *,skb,int,offset)234 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
235 	   int, offset)
236 {
237 	return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
238 					 offset);
239 }
240 
BPF_CALL_4(bpf_skb_load_helper_16,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)241 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
242 	   data, int, headlen, int, offset)
243 {
244 	__be16 tmp, *ptr;
245 	const int len = sizeof(tmp);
246 
247 	if (offset >= 0) {
248 		if (headlen - offset >= len)
249 			return get_unaligned_be16(data + offset);
250 		if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
251 			return be16_to_cpu(tmp);
252 	} else {
253 		ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
254 		if (likely(ptr))
255 			return get_unaligned_be16(ptr);
256 	}
257 
258 	return -EFAULT;
259 }
260 
BPF_CALL_2(bpf_skb_load_helper_16_no_cache,const struct sk_buff *,skb,int,offset)261 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
262 	   int, offset)
263 {
264 	return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
265 					  offset);
266 }
267 
BPF_CALL_4(bpf_skb_load_helper_32,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)268 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
269 	   data, int, headlen, int, offset)
270 {
271 	__be32 tmp, *ptr;
272 	const int len = sizeof(tmp);
273 
274 	if (likely(offset >= 0)) {
275 		if (headlen - offset >= len)
276 			return get_unaligned_be32(data + offset);
277 		if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
278 			return be32_to_cpu(tmp);
279 	} else {
280 		ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
281 		if (likely(ptr))
282 			return get_unaligned_be32(ptr);
283 	}
284 
285 	return -EFAULT;
286 }
287 
BPF_CALL_2(bpf_skb_load_helper_32_no_cache,const struct sk_buff *,skb,int,offset)288 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
289 	   int, offset)
290 {
291 	return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
292 					  offset);
293 }
294 
convert_skb_access(int skb_field,int dst_reg,int src_reg,struct bpf_insn * insn_buf)295 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
296 			      struct bpf_insn *insn_buf)
297 {
298 	struct bpf_insn *insn = insn_buf;
299 
300 	switch (skb_field) {
301 	case SKF_AD_MARK:
302 		BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4);
303 
304 		*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
305 				      offsetof(struct sk_buff, mark));
306 		break;
307 
308 	case SKF_AD_PKTTYPE:
309 		*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET);
310 		*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
311 #ifdef __BIG_ENDIAN_BITFIELD
312 		*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
313 #endif
314 		break;
315 
316 	case SKF_AD_QUEUE:
317 		BUILD_BUG_ON(sizeof_field(struct sk_buff, queue_mapping) != 2);
318 
319 		*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
320 				      offsetof(struct sk_buff, queue_mapping));
321 		break;
322 
323 	case SKF_AD_VLAN_TAG:
324 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_tci) != 2);
325 
326 		/* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
327 		*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
328 				      offsetof(struct sk_buff, vlan_tci));
329 		break;
330 	case SKF_AD_VLAN_TAG_PRESENT:
331 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_all) != 4);
332 		*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
333 				      offsetof(struct sk_buff, vlan_all));
334 		*insn++ = BPF_JMP_IMM(BPF_JEQ, dst_reg, 0, 1);
335 		*insn++ = BPF_ALU32_IMM(BPF_MOV, dst_reg, 1);
336 		break;
337 	}
338 
339 	return insn - insn_buf;
340 }
341 
convert_bpf_extensions(struct sock_filter * fp,struct bpf_insn ** insnp)342 static bool convert_bpf_extensions(struct sock_filter *fp,
343 				   struct bpf_insn **insnp)
344 {
345 	struct bpf_insn *insn = *insnp;
346 	u32 cnt;
347 
348 	switch (fp->k) {
349 	case SKF_AD_OFF + SKF_AD_PROTOCOL:
350 		BUILD_BUG_ON(sizeof_field(struct sk_buff, protocol) != 2);
351 
352 		/* A = *(u16 *) (CTX + offsetof(protocol)) */
353 		*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
354 				      offsetof(struct sk_buff, protocol));
355 		/* A = ntohs(A) [emitting a nop or swap16] */
356 		*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
357 		break;
358 
359 	case SKF_AD_OFF + SKF_AD_PKTTYPE:
360 		cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
361 		insn += cnt - 1;
362 		break;
363 
364 	case SKF_AD_OFF + SKF_AD_IFINDEX:
365 	case SKF_AD_OFF + SKF_AD_HATYPE:
366 		BUILD_BUG_ON(sizeof_field(struct net_device, ifindex) != 4);
367 		BUILD_BUG_ON(sizeof_field(struct net_device, type) != 2);
368 
369 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
370 				      BPF_REG_TMP, BPF_REG_CTX,
371 				      offsetof(struct sk_buff, dev));
372 		/* if (tmp != 0) goto pc + 1 */
373 		*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
374 		*insn++ = BPF_EXIT_INSN();
375 		if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
376 			*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
377 					    offsetof(struct net_device, ifindex));
378 		else
379 			*insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
380 					    offsetof(struct net_device, type));
381 		break;
382 
383 	case SKF_AD_OFF + SKF_AD_MARK:
384 		cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
385 		insn += cnt - 1;
386 		break;
387 
388 	case SKF_AD_OFF + SKF_AD_RXHASH:
389 		BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4);
390 
391 		*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
392 				    offsetof(struct sk_buff, hash));
393 		break;
394 
395 	case SKF_AD_OFF + SKF_AD_QUEUE:
396 		cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
397 		insn += cnt - 1;
398 		break;
399 
400 	case SKF_AD_OFF + SKF_AD_VLAN_TAG:
401 		cnt = convert_skb_access(SKF_AD_VLAN_TAG,
402 					 BPF_REG_A, BPF_REG_CTX, insn);
403 		insn += cnt - 1;
404 		break;
405 
406 	case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
407 		cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
408 					 BPF_REG_A, BPF_REG_CTX, insn);
409 		insn += cnt - 1;
410 		break;
411 
412 	case SKF_AD_OFF + SKF_AD_VLAN_TPID:
413 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_proto) != 2);
414 
415 		/* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
416 		*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
417 				      offsetof(struct sk_buff, vlan_proto));
418 		/* A = ntohs(A) [emitting a nop or swap16] */
419 		*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
420 		break;
421 
422 	case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
423 	case SKF_AD_OFF + SKF_AD_NLATTR:
424 	case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
425 	case SKF_AD_OFF + SKF_AD_CPU:
426 	case SKF_AD_OFF + SKF_AD_RANDOM:
427 		/* arg1 = CTX */
428 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
429 		/* arg2 = A */
430 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
431 		/* arg3 = X */
432 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
433 		/* Emit call(arg1=CTX, arg2=A, arg3=X) */
434 		switch (fp->k) {
435 		case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
436 			*insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
437 			break;
438 		case SKF_AD_OFF + SKF_AD_NLATTR:
439 			*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
440 			break;
441 		case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
442 			*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
443 			break;
444 		case SKF_AD_OFF + SKF_AD_CPU:
445 			*insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
446 			break;
447 		case SKF_AD_OFF + SKF_AD_RANDOM:
448 			*insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
449 			bpf_user_rnd_init_once();
450 			break;
451 		}
452 		break;
453 
454 	case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
455 		/* A ^= X */
456 		*insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
457 		break;
458 
459 	default:
460 		/* This is just a dummy call to avoid letting the compiler
461 		 * evict __bpf_call_base() as an optimization. Placed here
462 		 * where no-one bothers.
463 		 */
464 		BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
465 		return false;
466 	}
467 
468 	*insnp = insn;
469 	return true;
470 }
471 
convert_bpf_ld_abs(struct sock_filter * fp,struct bpf_insn ** insnp)472 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
473 {
474 	const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
475 	int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
476 	bool endian = BPF_SIZE(fp->code) == BPF_H ||
477 		      BPF_SIZE(fp->code) == BPF_W;
478 	bool indirect = BPF_MODE(fp->code) == BPF_IND;
479 	const int ip_align = NET_IP_ALIGN;
480 	struct bpf_insn *insn = *insnp;
481 	int offset = fp->k;
482 
483 	if (!indirect &&
484 	    ((unaligned_ok && offset >= 0) ||
485 	     (!unaligned_ok && offset >= 0 &&
486 	      offset + ip_align >= 0 &&
487 	      offset + ip_align % size == 0))) {
488 		bool ldx_off_ok = offset <= S16_MAX;
489 
490 		*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
491 		if (offset)
492 			*insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
493 		*insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
494 				      size, 2 + endian + (!ldx_off_ok * 2));
495 		if (ldx_off_ok) {
496 			*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
497 					      BPF_REG_D, offset);
498 		} else {
499 			*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
500 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
501 			*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
502 					      BPF_REG_TMP, 0);
503 		}
504 		if (endian)
505 			*insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
506 		*insn++ = BPF_JMP_A(8);
507 	}
508 
509 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
510 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
511 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
512 	if (!indirect) {
513 		*insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
514 	} else {
515 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
516 		if (fp->k)
517 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
518 	}
519 
520 	switch (BPF_SIZE(fp->code)) {
521 	case BPF_B:
522 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
523 		break;
524 	case BPF_H:
525 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
526 		break;
527 	case BPF_W:
528 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
529 		break;
530 	default:
531 		return false;
532 	}
533 
534 	*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
535 	*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
536 	*insn   = BPF_EXIT_INSN();
537 
538 	*insnp = insn;
539 	return true;
540 }
541 
542 /**
543  *	bpf_convert_filter - convert filter program
544  *	@prog: the user passed filter program
545  *	@len: the length of the user passed filter program
546  *	@new_prog: allocated 'struct bpf_prog' or NULL
547  *	@new_len: pointer to store length of converted program
548  *	@seen_ld_abs: bool whether we've seen ld_abs/ind
549  *
550  * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
551  * style extended BPF (eBPF).
552  * Conversion workflow:
553  *
554  * 1) First pass for calculating the new program length:
555  *   bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
556  *
557  * 2) 2nd pass to remap in two passes: 1st pass finds new
558  *    jump offsets, 2nd pass remapping:
559  *   bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
560  */
bpf_convert_filter(struct sock_filter * prog,int len,struct bpf_prog * new_prog,int * new_len,bool * seen_ld_abs)561 static int bpf_convert_filter(struct sock_filter *prog, int len,
562 			      struct bpf_prog *new_prog, int *new_len,
563 			      bool *seen_ld_abs)
564 {
565 	int new_flen = 0, pass = 0, target, i, stack_off;
566 	struct bpf_insn *new_insn, *first_insn = NULL;
567 	struct sock_filter *fp;
568 	int *addrs = NULL;
569 	u8 bpf_src;
570 
571 	BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
572 	BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
573 
574 	if (len <= 0 || len > BPF_MAXINSNS)
575 		return -EINVAL;
576 
577 	if (new_prog) {
578 		first_insn = new_prog->insnsi;
579 		addrs = kcalloc(len, sizeof(*addrs),
580 				GFP_KERNEL | __GFP_NOWARN);
581 		if (!addrs)
582 			return -ENOMEM;
583 	}
584 
585 do_pass:
586 	new_insn = first_insn;
587 	fp = prog;
588 
589 	/* Classic BPF related prologue emission. */
590 	if (new_prog) {
591 		/* Classic BPF expects A and X to be reset first. These need
592 		 * to be guaranteed to be the first two instructions.
593 		 */
594 		*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
595 		*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
596 
597 		/* All programs must keep CTX in callee saved BPF_REG_CTX.
598 		 * In eBPF case it's done by the compiler, here we need to
599 		 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
600 		 */
601 		*new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
602 		if (*seen_ld_abs) {
603 			/* For packet access in classic BPF, cache skb->data
604 			 * in callee-saved BPF R8 and skb->len - skb->data_len
605 			 * (headlen) in BPF R9. Since classic BPF is read-only
606 			 * on CTX, we only need to cache it once.
607 			 */
608 			*new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
609 						  BPF_REG_D, BPF_REG_CTX,
610 						  offsetof(struct sk_buff, data));
611 			*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
612 						  offsetof(struct sk_buff, len));
613 			*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
614 						  offsetof(struct sk_buff, data_len));
615 			*new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
616 		}
617 	} else {
618 		new_insn += 3;
619 	}
620 
621 	for (i = 0; i < len; fp++, i++) {
622 		struct bpf_insn tmp_insns[32] = { };
623 		struct bpf_insn *insn = tmp_insns;
624 
625 		if (addrs)
626 			addrs[i] = new_insn - first_insn;
627 
628 		switch (fp->code) {
629 		/* All arithmetic insns and skb loads map as-is. */
630 		case BPF_ALU | BPF_ADD | BPF_X:
631 		case BPF_ALU | BPF_ADD | BPF_K:
632 		case BPF_ALU | BPF_SUB | BPF_X:
633 		case BPF_ALU | BPF_SUB | BPF_K:
634 		case BPF_ALU | BPF_AND | BPF_X:
635 		case BPF_ALU | BPF_AND | BPF_K:
636 		case BPF_ALU | BPF_OR | BPF_X:
637 		case BPF_ALU | BPF_OR | BPF_K:
638 		case BPF_ALU | BPF_LSH | BPF_X:
639 		case BPF_ALU | BPF_LSH | BPF_K:
640 		case BPF_ALU | BPF_RSH | BPF_X:
641 		case BPF_ALU | BPF_RSH | BPF_K:
642 		case BPF_ALU | BPF_XOR | BPF_X:
643 		case BPF_ALU | BPF_XOR | BPF_K:
644 		case BPF_ALU | BPF_MUL | BPF_X:
645 		case BPF_ALU | BPF_MUL | BPF_K:
646 		case BPF_ALU | BPF_DIV | BPF_X:
647 		case BPF_ALU | BPF_DIV | BPF_K:
648 		case BPF_ALU | BPF_MOD | BPF_X:
649 		case BPF_ALU | BPF_MOD | BPF_K:
650 		case BPF_ALU | BPF_NEG:
651 		case BPF_LD | BPF_ABS | BPF_W:
652 		case BPF_LD | BPF_ABS | BPF_H:
653 		case BPF_LD | BPF_ABS | BPF_B:
654 		case BPF_LD | BPF_IND | BPF_W:
655 		case BPF_LD | BPF_IND | BPF_H:
656 		case BPF_LD | BPF_IND | BPF_B:
657 			/* Check for overloaded BPF extension and
658 			 * directly convert it if found, otherwise
659 			 * just move on with mapping.
660 			 */
661 			if (BPF_CLASS(fp->code) == BPF_LD &&
662 			    BPF_MODE(fp->code) == BPF_ABS &&
663 			    convert_bpf_extensions(fp, &insn))
664 				break;
665 			if (BPF_CLASS(fp->code) == BPF_LD &&
666 			    convert_bpf_ld_abs(fp, &insn)) {
667 				*seen_ld_abs = true;
668 				break;
669 			}
670 
671 			if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
672 			    fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
673 				*insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
674 				/* Error with exception code on div/mod by 0.
675 				 * For cBPF programs, this was always return 0.
676 				 */
677 				*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
678 				*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
679 				*insn++ = BPF_EXIT_INSN();
680 			}
681 
682 			*insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
683 			break;
684 
685 		/* Jump transformation cannot use BPF block macros
686 		 * everywhere as offset calculation and target updates
687 		 * require a bit more work than the rest, i.e. jump
688 		 * opcodes map as-is, but offsets need adjustment.
689 		 */
690 
691 #define BPF_EMIT_JMP							\
692 	do {								\
693 		const s32 off_min = S16_MIN, off_max = S16_MAX;		\
694 		s32 off;						\
695 									\
696 		if (target >= len || target < 0)			\
697 			goto err;					\
698 		off = addrs ? addrs[target] - addrs[i] - 1 : 0;		\
699 		/* Adjust pc relative offset for 2nd or 3rd insn. */	\
700 		off -= insn - tmp_insns;				\
701 		/* Reject anything not fitting into insn->off. */	\
702 		if (off < off_min || off > off_max)			\
703 			goto err;					\
704 		insn->off = off;					\
705 	} while (0)
706 
707 		case BPF_JMP | BPF_JA:
708 			target = i + fp->k + 1;
709 			insn->code = fp->code;
710 			BPF_EMIT_JMP;
711 			break;
712 
713 		case BPF_JMP | BPF_JEQ | BPF_K:
714 		case BPF_JMP | BPF_JEQ | BPF_X:
715 		case BPF_JMP | BPF_JSET | BPF_K:
716 		case BPF_JMP | BPF_JSET | BPF_X:
717 		case BPF_JMP | BPF_JGT | BPF_K:
718 		case BPF_JMP | BPF_JGT | BPF_X:
719 		case BPF_JMP | BPF_JGE | BPF_K:
720 		case BPF_JMP | BPF_JGE | BPF_X:
721 			if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
722 				/* BPF immediates are signed, zero extend
723 				 * immediate into tmp register and use it
724 				 * in compare insn.
725 				 */
726 				*insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
727 
728 				insn->dst_reg = BPF_REG_A;
729 				insn->src_reg = BPF_REG_TMP;
730 				bpf_src = BPF_X;
731 			} else {
732 				insn->dst_reg = BPF_REG_A;
733 				insn->imm = fp->k;
734 				bpf_src = BPF_SRC(fp->code);
735 				insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
736 			}
737 
738 			/* Common case where 'jump_false' is next insn. */
739 			if (fp->jf == 0) {
740 				insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
741 				target = i + fp->jt + 1;
742 				BPF_EMIT_JMP;
743 				break;
744 			}
745 
746 			/* Convert some jumps when 'jump_true' is next insn. */
747 			if (fp->jt == 0) {
748 				switch (BPF_OP(fp->code)) {
749 				case BPF_JEQ:
750 					insn->code = BPF_JMP | BPF_JNE | bpf_src;
751 					break;
752 				case BPF_JGT:
753 					insn->code = BPF_JMP | BPF_JLE | bpf_src;
754 					break;
755 				case BPF_JGE:
756 					insn->code = BPF_JMP | BPF_JLT | bpf_src;
757 					break;
758 				default:
759 					goto jmp_rest;
760 				}
761 
762 				target = i + fp->jf + 1;
763 				BPF_EMIT_JMP;
764 				break;
765 			}
766 jmp_rest:
767 			/* Other jumps are mapped into two insns: Jxx and JA. */
768 			target = i + fp->jt + 1;
769 			insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
770 			BPF_EMIT_JMP;
771 			insn++;
772 
773 			insn->code = BPF_JMP | BPF_JA;
774 			target = i + fp->jf + 1;
775 			BPF_EMIT_JMP;
776 			break;
777 
778 		/* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
779 		case BPF_LDX | BPF_MSH | BPF_B: {
780 			struct sock_filter tmp = {
781 				.code	= BPF_LD | BPF_ABS | BPF_B,
782 				.k	= fp->k,
783 			};
784 
785 			*seen_ld_abs = true;
786 
787 			/* X = A */
788 			*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
789 			/* A = BPF_R0 = *(u8 *) (skb->data + K) */
790 			convert_bpf_ld_abs(&tmp, &insn);
791 			insn++;
792 			/* A &= 0xf */
793 			*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
794 			/* A <<= 2 */
795 			*insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
796 			/* tmp = X */
797 			*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
798 			/* X = A */
799 			*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
800 			/* A = tmp */
801 			*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
802 			break;
803 		}
804 		/* RET_K is remaped into 2 insns. RET_A case doesn't need an
805 		 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
806 		 */
807 		case BPF_RET | BPF_A:
808 		case BPF_RET | BPF_K:
809 			if (BPF_RVAL(fp->code) == BPF_K)
810 				*insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
811 							0, fp->k);
812 			*insn = BPF_EXIT_INSN();
813 			break;
814 
815 		/* Store to stack. */
816 		case BPF_ST:
817 		case BPF_STX:
818 			stack_off = fp->k * 4  + 4;
819 			*insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
820 					    BPF_ST ? BPF_REG_A : BPF_REG_X,
821 					    -stack_off);
822 			/* check_load_and_stores() verifies that classic BPF can
823 			 * load from stack only after write, so tracking
824 			 * stack_depth for ST|STX insns is enough
825 			 */
826 			if (new_prog && new_prog->aux->stack_depth < stack_off)
827 				new_prog->aux->stack_depth = stack_off;
828 			break;
829 
830 		/* Load from stack. */
831 		case BPF_LD | BPF_MEM:
832 		case BPF_LDX | BPF_MEM:
833 			stack_off = fp->k * 4  + 4;
834 			*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD  ?
835 					    BPF_REG_A : BPF_REG_X, BPF_REG_FP,
836 					    -stack_off);
837 			break;
838 
839 		/* A = K or X = K */
840 		case BPF_LD | BPF_IMM:
841 		case BPF_LDX | BPF_IMM:
842 			*insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
843 					      BPF_REG_A : BPF_REG_X, fp->k);
844 			break;
845 
846 		/* X = A */
847 		case BPF_MISC | BPF_TAX:
848 			*insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
849 			break;
850 
851 		/* A = X */
852 		case BPF_MISC | BPF_TXA:
853 			*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
854 			break;
855 
856 		/* A = skb->len or X = skb->len */
857 		case BPF_LD | BPF_W | BPF_LEN:
858 		case BPF_LDX | BPF_W | BPF_LEN:
859 			*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
860 					    BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
861 					    offsetof(struct sk_buff, len));
862 			break;
863 
864 		/* Access seccomp_data fields. */
865 		case BPF_LDX | BPF_ABS | BPF_W:
866 			/* A = *(u32 *) (ctx + K) */
867 			*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
868 			break;
869 
870 		/* Unknown instruction. */
871 		default:
872 			goto err;
873 		}
874 
875 		insn++;
876 		if (new_prog)
877 			memcpy(new_insn, tmp_insns,
878 			       sizeof(*insn) * (insn - tmp_insns));
879 		new_insn += insn - tmp_insns;
880 	}
881 
882 	if (!new_prog) {
883 		/* Only calculating new length. */
884 		*new_len = new_insn - first_insn;
885 		if (*seen_ld_abs)
886 			*new_len += 4; /* Prologue bits. */
887 		return 0;
888 	}
889 
890 	pass++;
891 	if (new_flen != new_insn - first_insn) {
892 		new_flen = new_insn - first_insn;
893 		if (pass > 2)
894 			goto err;
895 		goto do_pass;
896 	}
897 
898 	kfree(addrs);
899 	BUG_ON(*new_len != new_flen);
900 	return 0;
901 err:
902 	kfree(addrs);
903 	return -EINVAL;
904 }
905 
906 /* Security:
907  *
908  * As we dont want to clear mem[] array for each packet going through
909  * __bpf_prog_run(), we check that filter loaded by user never try to read
910  * a cell if not previously written, and we check all branches to be sure
911  * a malicious user doesn't try to abuse us.
912  */
check_load_and_stores(const struct sock_filter * filter,int flen)913 static int check_load_and_stores(const struct sock_filter *filter, int flen)
914 {
915 	u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
916 	int pc, ret = 0;
917 
918 	BUILD_BUG_ON(BPF_MEMWORDS > 16);
919 
920 	masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
921 	if (!masks)
922 		return -ENOMEM;
923 
924 	memset(masks, 0xff, flen * sizeof(*masks));
925 
926 	for (pc = 0; pc < flen; pc++) {
927 		memvalid &= masks[pc];
928 
929 		switch (filter[pc].code) {
930 		case BPF_ST:
931 		case BPF_STX:
932 			memvalid |= (1 << filter[pc].k);
933 			break;
934 		case BPF_LD | BPF_MEM:
935 		case BPF_LDX | BPF_MEM:
936 			if (!(memvalid & (1 << filter[pc].k))) {
937 				ret = -EINVAL;
938 				goto error;
939 			}
940 			break;
941 		case BPF_JMP | BPF_JA:
942 			/* A jump must set masks on target */
943 			masks[pc + 1 + filter[pc].k] &= memvalid;
944 			memvalid = ~0;
945 			break;
946 		case BPF_JMP | BPF_JEQ | BPF_K:
947 		case BPF_JMP | BPF_JEQ | BPF_X:
948 		case BPF_JMP | BPF_JGE | BPF_K:
949 		case BPF_JMP | BPF_JGE | BPF_X:
950 		case BPF_JMP | BPF_JGT | BPF_K:
951 		case BPF_JMP | BPF_JGT | BPF_X:
952 		case BPF_JMP | BPF_JSET | BPF_K:
953 		case BPF_JMP | BPF_JSET | BPF_X:
954 			/* A jump must set masks on targets */
955 			masks[pc + 1 + filter[pc].jt] &= memvalid;
956 			masks[pc + 1 + filter[pc].jf] &= memvalid;
957 			memvalid = ~0;
958 			break;
959 		}
960 	}
961 error:
962 	kfree(masks);
963 	return ret;
964 }
965 
chk_code_allowed(u16 code_to_probe)966 static bool chk_code_allowed(u16 code_to_probe)
967 {
968 	static const bool codes[] = {
969 		/* 32 bit ALU operations */
970 		[BPF_ALU | BPF_ADD | BPF_K] = true,
971 		[BPF_ALU | BPF_ADD | BPF_X] = true,
972 		[BPF_ALU | BPF_SUB | BPF_K] = true,
973 		[BPF_ALU | BPF_SUB | BPF_X] = true,
974 		[BPF_ALU | BPF_MUL | BPF_K] = true,
975 		[BPF_ALU | BPF_MUL | BPF_X] = true,
976 		[BPF_ALU | BPF_DIV | BPF_K] = true,
977 		[BPF_ALU | BPF_DIV | BPF_X] = true,
978 		[BPF_ALU | BPF_MOD | BPF_K] = true,
979 		[BPF_ALU | BPF_MOD | BPF_X] = true,
980 		[BPF_ALU | BPF_AND | BPF_K] = true,
981 		[BPF_ALU | BPF_AND | BPF_X] = true,
982 		[BPF_ALU | BPF_OR | BPF_K] = true,
983 		[BPF_ALU | BPF_OR | BPF_X] = true,
984 		[BPF_ALU | BPF_XOR | BPF_K] = true,
985 		[BPF_ALU | BPF_XOR | BPF_X] = true,
986 		[BPF_ALU | BPF_LSH | BPF_K] = true,
987 		[BPF_ALU | BPF_LSH | BPF_X] = true,
988 		[BPF_ALU | BPF_RSH | BPF_K] = true,
989 		[BPF_ALU | BPF_RSH | BPF_X] = true,
990 		[BPF_ALU | BPF_NEG] = true,
991 		/* Load instructions */
992 		[BPF_LD | BPF_W | BPF_ABS] = true,
993 		[BPF_LD | BPF_H | BPF_ABS] = true,
994 		[BPF_LD | BPF_B | BPF_ABS] = true,
995 		[BPF_LD | BPF_W | BPF_LEN] = true,
996 		[BPF_LD | BPF_W | BPF_IND] = true,
997 		[BPF_LD | BPF_H | BPF_IND] = true,
998 		[BPF_LD | BPF_B | BPF_IND] = true,
999 		[BPF_LD | BPF_IMM] = true,
1000 		[BPF_LD | BPF_MEM] = true,
1001 		[BPF_LDX | BPF_W | BPF_LEN] = true,
1002 		[BPF_LDX | BPF_B | BPF_MSH] = true,
1003 		[BPF_LDX | BPF_IMM] = true,
1004 		[BPF_LDX | BPF_MEM] = true,
1005 		/* Store instructions */
1006 		[BPF_ST] = true,
1007 		[BPF_STX] = true,
1008 		/* Misc instructions */
1009 		[BPF_MISC | BPF_TAX] = true,
1010 		[BPF_MISC | BPF_TXA] = true,
1011 		/* Return instructions */
1012 		[BPF_RET | BPF_K] = true,
1013 		[BPF_RET | BPF_A] = true,
1014 		/* Jump instructions */
1015 		[BPF_JMP | BPF_JA] = true,
1016 		[BPF_JMP | BPF_JEQ | BPF_K] = true,
1017 		[BPF_JMP | BPF_JEQ | BPF_X] = true,
1018 		[BPF_JMP | BPF_JGE | BPF_K] = true,
1019 		[BPF_JMP | BPF_JGE | BPF_X] = true,
1020 		[BPF_JMP | BPF_JGT | BPF_K] = true,
1021 		[BPF_JMP | BPF_JGT | BPF_X] = true,
1022 		[BPF_JMP | BPF_JSET | BPF_K] = true,
1023 		[BPF_JMP | BPF_JSET | BPF_X] = true,
1024 	};
1025 
1026 	if (code_to_probe >= ARRAY_SIZE(codes))
1027 		return false;
1028 
1029 	return codes[code_to_probe];
1030 }
1031 
bpf_check_basics_ok(const struct sock_filter * filter,unsigned int flen)1032 static bool bpf_check_basics_ok(const struct sock_filter *filter,
1033 				unsigned int flen)
1034 {
1035 	if (filter == NULL)
1036 		return false;
1037 	if (flen == 0 || flen > BPF_MAXINSNS)
1038 		return false;
1039 
1040 	return true;
1041 }
1042 
1043 /**
1044  *	bpf_check_classic - verify socket filter code
1045  *	@filter: filter to verify
1046  *	@flen: length of filter
1047  *
1048  * Check the user's filter code. If we let some ugly
1049  * filter code slip through kaboom! The filter must contain
1050  * no references or jumps that are out of range, no illegal
1051  * instructions, and must end with a RET instruction.
1052  *
1053  * All jumps are forward as they are not signed.
1054  *
1055  * Returns 0 if the rule set is legal or -EINVAL if not.
1056  */
bpf_check_classic(const struct sock_filter * filter,unsigned int flen)1057 static int bpf_check_classic(const struct sock_filter *filter,
1058 			     unsigned int flen)
1059 {
1060 	bool anc_found;
1061 	int pc;
1062 
1063 	/* Check the filter code now */
1064 	for (pc = 0; pc < flen; pc++) {
1065 		const struct sock_filter *ftest = &filter[pc];
1066 
1067 		/* May we actually operate on this code? */
1068 		if (!chk_code_allowed(ftest->code))
1069 			return -EINVAL;
1070 
1071 		/* Some instructions need special checks */
1072 		switch (ftest->code) {
1073 		case BPF_ALU | BPF_DIV | BPF_K:
1074 		case BPF_ALU | BPF_MOD | BPF_K:
1075 			/* Check for division by zero */
1076 			if (ftest->k == 0)
1077 				return -EINVAL;
1078 			break;
1079 		case BPF_ALU | BPF_LSH | BPF_K:
1080 		case BPF_ALU | BPF_RSH | BPF_K:
1081 			if (ftest->k >= 32)
1082 				return -EINVAL;
1083 			break;
1084 		case BPF_LD | BPF_MEM:
1085 		case BPF_LDX | BPF_MEM:
1086 		case BPF_ST:
1087 		case BPF_STX:
1088 			/* Check for invalid memory addresses */
1089 			if (ftest->k >= BPF_MEMWORDS)
1090 				return -EINVAL;
1091 			break;
1092 		case BPF_JMP | BPF_JA:
1093 			/* Note, the large ftest->k might cause loops.
1094 			 * Compare this with conditional jumps below,
1095 			 * where offsets are limited. --ANK (981016)
1096 			 */
1097 			if (ftest->k >= (unsigned int)(flen - pc - 1))
1098 				return -EINVAL;
1099 			break;
1100 		case BPF_JMP | BPF_JEQ | BPF_K:
1101 		case BPF_JMP | BPF_JEQ | BPF_X:
1102 		case BPF_JMP | BPF_JGE | BPF_K:
1103 		case BPF_JMP | BPF_JGE | BPF_X:
1104 		case BPF_JMP | BPF_JGT | BPF_K:
1105 		case BPF_JMP | BPF_JGT | BPF_X:
1106 		case BPF_JMP | BPF_JSET | BPF_K:
1107 		case BPF_JMP | BPF_JSET | BPF_X:
1108 			/* Both conditionals must be safe */
1109 			if (pc + ftest->jt + 1 >= flen ||
1110 			    pc + ftest->jf + 1 >= flen)
1111 				return -EINVAL;
1112 			break;
1113 		case BPF_LD | BPF_W | BPF_ABS:
1114 		case BPF_LD | BPF_H | BPF_ABS:
1115 		case BPF_LD | BPF_B | BPF_ABS:
1116 			anc_found = false;
1117 			if (bpf_anc_helper(ftest) & BPF_ANC)
1118 				anc_found = true;
1119 			/* Ancillary operation unknown or unsupported */
1120 			if (anc_found == false && ftest->k >= SKF_AD_OFF)
1121 				return -EINVAL;
1122 		}
1123 	}
1124 
1125 	/* Last instruction must be a RET code */
1126 	switch (filter[flen - 1].code) {
1127 	case BPF_RET | BPF_K:
1128 	case BPF_RET | BPF_A:
1129 		return check_load_and_stores(filter, flen);
1130 	}
1131 
1132 	return -EINVAL;
1133 }
1134 
bpf_prog_store_orig_filter(struct bpf_prog * fp,const struct sock_fprog * fprog)1135 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
1136 				      const struct sock_fprog *fprog)
1137 {
1138 	unsigned int fsize = bpf_classic_proglen(fprog);
1139 	struct sock_fprog_kern *fkprog;
1140 
1141 	fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
1142 	if (!fp->orig_prog)
1143 		return -ENOMEM;
1144 
1145 	fkprog = fp->orig_prog;
1146 	fkprog->len = fprog->len;
1147 
1148 	fkprog->filter = kmemdup(fp->insns, fsize,
1149 				 GFP_KERNEL | __GFP_NOWARN);
1150 	if (!fkprog->filter) {
1151 		kfree(fp->orig_prog);
1152 		return -ENOMEM;
1153 	}
1154 
1155 	return 0;
1156 }
1157 
bpf_release_orig_filter(struct bpf_prog * fp)1158 static void bpf_release_orig_filter(struct bpf_prog *fp)
1159 {
1160 	struct sock_fprog_kern *fprog = fp->orig_prog;
1161 
1162 	if (fprog) {
1163 		kfree(fprog->filter);
1164 		kfree(fprog);
1165 	}
1166 }
1167 
__bpf_prog_release(struct bpf_prog * prog)1168 static void __bpf_prog_release(struct bpf_prog *prog)
1169 {
1170 	if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
1171 		bpf_prog_put(prog);
1172 	} else {
1173 		bpf_release_orig_filter(prog);
1174 		bpf_prog_free(prog);
1175 	}
1176 }
1177 
__sk_filter_release(struct sk_filter * fp)1178 static void __sk_filter_release(struct sk_filter *fp)
1179 {
1180 	__bpf_prog_release(fp->prog);
1181 	kfree(fp);
1182 }
1183 
1184 /**
1185  * 	sk_filter_release_rcu - Release a socket filter by rcu_head
1186  *	@rcu: rcu_head that contains the sk_filter to free
1187  */
sk_filter_release_rcu(struct rcu_head * rcu)1188 static void sk_filter_release_rcu(struct rcu_head *rcu)
1189 {
1190 	struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
1191 
1192 	__sk_filter_release(fp);
1193 }
1194 
1195 /**
1196  *	sk_filter_release - release a socket filter
1197  *	@fp: filter to remove
1198  *
1199  *	Remove a filter from a socket and release its resources.
1200  */
sk_filter_release(struct sk_filter * fp)1201 static void sk_filter_release(struct sk_filter *fp)
1202 {
1203 	if (refcount_dec_and_test(&fp->refcnt))
1204 		call_rcu(&fp->rcu, sk_filter_release_rcu);
1205 }
1206 
sk_filter_uncharge(struct sock * sk,struct sk_filter * fp)1207 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1208 {
1209 	u32 filter_size = bpf_prog_size(fp->prog->len);
1210 
1211 	atomic_sub(filter_size, &sk->sk_omem_alloc);
1212 	sk_filter_release(fp);
1213 }
1214 
1215 /* try to charge the socket memory if there is space available
1216  * return true on success
1217  */
__sk_filter_charge(struct sock * sk,struct sk_filter * fp)1218 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1219 {
1220 	u32 filter_size = bpf_prog_size(fp->prog->len);
1221 	int optmem_max = READ_ONCE(sysctl_optmem_max);
1222 
1223 	/* same check as in sock_kmalloc() */
1224 	if (filter_size <= optmem_max &&
1225 	    atomic_read(&sk->sk_omem_alloc) + filter_size < optmem_max) {
1226 		atomic_add(filter_size, &sk->sk_omem_alloc);
1227 		return true;
1228 	}
1229 	return false;
1230 }
1231 
sk_filter_charge(struct sock * sk,struct sk_filter * fp)1232 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1233 {
1234 	if (!refcount_inc_not_zero(&fp->refcnt))
1235 		return false;
1236 
1237 	if (!__sk_filter_charge(sk, fp)) {
1238 		sk_filter_release(fp);
1239 		return false;
1240 	}
1241 	return true;
1242 }
1243 
bpf_migrate_filter(struct bpf_prog * fp)1244 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1245 {
1246 	struct sock_filter *old_prog;
1247 	struct bpf_prog *old_fp;
1248 	int err, new_len, old_len = fp->len;
1249 	bool seen_ld_abs = false;
1250 
1251 	/* We are free to overwrite insns et al right here as it won't be used at
1252 	 * this point in time anymore internally after the migration to the eBPF
1253 	 * instruction representation.
1254 	 */
1255 	BUILD_BUG_ON(sizeof(struct sock_filter) !=
1256 		     sizeof(struct bpf_insn));
1257 
1258 	/* Conversion cannot happen on overlapping memory areas,
1259 	 * so we need to keep the user BPF around until the 2nd
1260 	 * pass. At this time, the user BPF is stored in fp->insns.
1261 	 */
1262 	old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1263 			   GFP_KERNEL | __GFP_NOWARN);
1264 	if (!old_prog) {
1265 		err = -ENOMEM;
1266 		goto out_err;
1267 	}
1268 
1269 	/* 1st pass: calculate the new program length. */
1270 	err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
1271 				 &seen_ld_abs);
1272 	if (err)
1273 		goto out_err_free;
1274 
1275 	/* Expand fp for appending the new filter representation. */
1276 	old_fp = fp;
1277 	fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1278 	if (!fp) {
1279 		/* The old_fp is still around in case we couldn't
1280 		 * allocate new memory, so uncharge on that one.
1281 		 */
1282 		fp = old_fp;
1283 		err = -ENOMEM;
1284 		goto out_err_free;
1285 	}
1286 
1287 	fp->len = new_len;
1288 
1289 	/* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1290 	err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
1291 				 &seen_ld_abs);
1292 	if (err)
1293 		/* 2nd bpf_convert_filter() can fail only if it fails
1294 		 * to allocate memory, remapping must succeed. Note,
1295 		 * that at this time old_fp has already been released
1296 		 * by krealloc().
1297 		 */
1298 		goto out_err_free;
1299 
1300 	fp = bpf_prog_select_runtime(fp, &err);
1301 	if (err)
1302 		goto out_err_free;
1303 
1304 	kfree(old_prog);
1305 	return fp;
1306 
1307 out_err_free:
1308 	kfree(old_prog);
1309 out_err:
1310 	__bpf_prog_release(fp);
1311 	return ERR_PTR(err);
1312 }
1313 
bpf_prepare_filter(struct bpf_prog * fp,bpf_aux_classic_check_t trans)1314 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1315 					   bpf_aux_classic_check_t trans)
1316 {
1317 	int err;
1318 
1319 	fp->bpf_func = NULL;
1320 	fp->jited = 0;
1321 
1322 	err = bpf_check_classic(fp->insns, fp->len);
1323 	if (err) {
1324 		__bpf_prog_release(fp);
1325 		return ERR_PTR(err);
1326 	}
1327 
1328 	/* There might be additional checks and transformations
1329 	 * needed on classic filters, f.e. in case of seccomp.
1330 	 */
1331 	if (trans) {
1332 		err = trans(fp->insns, fp->len);
1333 		if (err) {
1334 			__bpf_prog_release(fp);
1335 			return ERR_PTR(err);
1336 		}
1337 	}
1338 
1339 	/* Probe if we can JIT compile the filter and if so, do
1340 	 * the compilation of the filter.
1341 	 */
1342 	bpf_jit_compile(fp);
1343 
1344 	/* JIT compiler couldn't process this filter, so do the eBPF translation
1345 	 * for the optimized interpreter.
1346 	 */
1347 	if (!fp->jited)
1348 		fp = bpf_migrate_filter(fp);
1349 
1350 	return fp;
1351 }
1352 
1353 /**
1354  *	bpf_prog_create - create an unattached filter
1355  *	@pfp: the unattached filter that is created
1356  *	@fprog: the filter program
1357  *
1358  * Create a filter independent of any socket. We first run some
1359  * sanity checks on it to make sure it does not explode on us later.
1360  * If an error occurs or there is insufficient memory for the filter
1361  * a negative errno code is returned. On success the return is zero.
1362  */
bpf_prog_create(struct bpf_prog ** pfp,struct sock_fprog_kern * fprog)1363 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1364 {
1365 	unsigned int fsize = bpf_classic_proglen(fprog);
1366 	struct bpf_prog *fp;
1367 
1368 	/* Make sure new filter is there and in the right amounts. */
1369 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1370 		return -EINVAL;
1371 
1372 	fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1373 	if (!fp)
1374 		return -ENOMEM;
1375 
1376 	memcpy(fp->insns, fprog->filter, fsize);
1377 
1378 	fp->len = fprog->len;
1379 	/* Since unattached filters are not copied back to user
1380 	 * space through sk_get_filter(), we do not need to hold
1381 	 * a copy here, and can spare us the work.
1382 	 */
1383 	fp->orig_prog = NULL;
1384 
1385 	/* bpf_prepare_filter() already takes care of freeing
1386 	 * memory in case something goes wrong.
1387 	 */
1388 	fp = bpf_prepare_filter(fp, NULL);
1389 	if (IS_ERR(fp))
1390 		return PTR_ERR(fp);
1391 
1392 	*pfp = fp;
1393 	return 0;
1394 }
1395 EXPORT_SYMBOL_GPL(bpf_prog_create);
1396 
1397 /**
1398  *	bpf_prog_create_from_user - create an unattached filter from user buffer
1399  *	@pfp: the unattached filter that is created
1400  *	@fprog: the filter program
1401  *	@trans: post-classic verifier transformation handler
1402  *	@save_orig: save classic BPF program
1403  *
1404  * This function effectively does the same as bpf_prog_create(), only
1405  * that it builds up its insns buffer from user space provided buffer.
1406  * It also allows for passing a bpf_aux_classic_check_t handler.
1407  */
bpf_prog_create_from_user(struct bpf_prog ** pfp,struct sock_fprog * fprog,bpf_aux_classic_check_t trans,bool save_orig)1408 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1409 			      bpf_aux_classic_check_t trans, bool save_orig)
1410 {
1411 	unsigned int fsize = bpf_classic_proglen(fprog);
1412 	struct bpf_prog *fp;
1413 	int err;
1414 
1415 	/* Make sure new filter is there and in the right amounts. */
1416 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1417 		return -EINVAL;
1418 
1419 	fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1420 	if (!fp)
1421 		return -ENOMEM;
1422 
1423 	if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1424 		__bpf_prog_free(fp);
1425 		return -EFAULT;
1426 	}
1427 
1428 	fp->len = fprog->len;
1429 	fp->orig_prog = NULL;
1430 
1431 	if (save_orig) {
1432 		err = bpf_prog_store_orig_filter(fp, fprog);
1433 		if (err) {
1434 			__bpf_prog_free(fp);
1435 			return -ENOMEM;
1436 		}
1437 	}
1438 
1439 	/* bpf_prepare_filter() already takes care of freeing
1440 	 * memory in case something goes wrong.
1441 	 */
1442 	fp = bpf_prepare_filter(fp, trans);
1443 	if (IS_ERR(fp))
1444 		return PTR_ERR(fp);
1445 
1446 	*pfp = fp;
1447 	return 0;
1448 }
1449 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1450 
bpf_prog_destroy(struct bpf_prog * fp)1451 void bpf_prog_destroy(struct bpf_prog *fp)
1452 {
1453 	__bpf_prog_release(fp);
1454 }
1455 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1456 
__sk_attach_prog(struct bpf_prog * prog,struct sock * sk)1457 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1458 {
1459 	struct sk_filter *fp, *old_fp;
1460 
1461 	fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1462 	if (!fp)
1463 		return -ENOMEM;
1464 
1465 	fp->prog = prog;
1466 
1467 	if (!__sk_filter_charge(sk, fp)) {
1468 		kfree(fp);
1469 		return -ENOMEM;
1470 	}
1471 	refcount_set(&fp->refcnt, 1);
1472 
1473 	old_fp = rcu_dereference_protected(sk->sk_filter,
1474 					   lockdep_sock_is_held(sk));
1475 	rcu_assign_pointer(sk->sk_filter, fp);
1476 
1477 	if (old_fp)
1478 		sk_filter_uncharge(sk, old_fp);
1479 
1480 	return 0;
1481 }
1482 
1483 static
__get_filter(struct sock_fprog * fprog,struct sock * sk)1484 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1485 {
1486 	unsigned int fsize = bpf_classic_proglen(fprog);
1487 	struct bpf_prog *prog;
1488 	int err;
1489 
1490 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1491 		return ERR_PTR(-EPERM);
1492 
1493 	/* Make sure new filter is there and in the right amounts. */
1494 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1495 		return ERR_PTR(-EINVAL);
1496 
1497 	prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1498 	if (!prog)
1499 		return ERR_PTR(-ENOMEM);
1500 
1501 	if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1502 		__bpf_prog_free(prog);
1503 		return ERR_PTR(-EFAULT);
1504 	}
1505 
1506 	prog->len = fprog->len;
1507 
1508 	err = bpf_prog_store_orig_filter(prog, fprog);
1509 	if (err) {
1510 		__bpf_prog_free(prog);
1511 		return ERR_PTR(-ENOMEM);
1512 	}
1513 
1514 	/* bpf_prepare_filter() already takes care of freeing
1515 	 * memory in case something goes wrong.
1516 	 */
1517 	return bpf_prepare_filter(prog, NULL);
1518 }
1519 
1520 /**
1521  *	sk_attach_filter - attach a socket filter
1522  *	@fprog: the filter program
1523  *	@sk: the socket to use
1524  *
1525  * Attach the user's filter code. We first run some sanity checks on
1526  * it to make sure it does not explode on us later. If an error
1527  * occurs or there is insufficient memory for the filter a negative
1528  * errno code is returned. On success the return is zero.
1529  */
sk_attach_filter(struct sock_fprog * fprog,struct sock * sk)1530 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1531 {
1532 	struct bpf_prog *prog = __get_filter(fprog, sk);
1533 	int err;
1534 
1535 	if (IS_ERR(prog))
1536 		return PTR_ERR(prog);
1537 
1538 	err = __sk_attach_prog(prog, sk);
1539 	if (err < 0) {
1540 		__bpf_prog_release(prog);
1541 		return err;
1542 	}
1543 
1544 	return 0;
1545 }
1546 EXPORT_SYMBOL_GPL(sk_attach_filter);
1547 
sk_reuseport_attach_filter(struct sock_fprog * fprog,struct sock * sk)1548 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1549 {
1550 	struct bpf_prog *prog = __get_filter(fprog, sk);
1551 	int err;
1552 
1553 	if (IS_ERR(prog))
1554 		return PTR_ERR(prog);
1555 
1556 	if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max))
1557 		err = -ENOMEM;
1558 	else
1559 		err = reuseport_attach_prog(sk, prog);
1560 
1561 	if (err)
1562 		__bpf_prog_release(prog);
1563 
1564 	return err;
1565 }
1566 
__get_bpf(u32 ufd,struct sock * sk)1567 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1568 {
1569 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1570 		return ERR_PTR(-EPERM);
1571 
1572 	return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1573 }
1574 
sk_attach_bpf(u32 ufd,struct sock * sk)1575 int sk_attach_bpf(u32 ufd, struct sock *sk)
1576 {
1577 	struct bpf_prog *prog = __get_bpf(ufd, sk);
1578 	int err;
1579 
1580 	if (IS_ERR(prog))
1581 		return PTR_ERR(prog);
1582 
1583 	err = __sk_attach_prog(prog, sk);
1584 	if (err < 0) {
1585 		bpf_prog_put(prog);
1586 		return err;
1587 	}
1588 
1589 	return 0;
1590 }
1591 
sk_reuseport_attach_bpf(u32 ufd,struct sock * sk)1592 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1593 {
1594 	struct bpf_prog *prog;
1595 	int err;
1596 
1597 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1598 		return -EPERM;
1599 
1600 	prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1601 	if (PTR_ERR(prog) == -EINVAL)
1602 		prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
1603 	if (IS_ERR(prog))
1604 		return PTR_ERR(prog);
1605 
1606 	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
1607 		/* Like other non BPF_PROG_TYPE_SOCKET_FILTER
1608 		 * bpf prog (e.g. sockmap).  It depends on the
1609 		 * limitation imposed by bpf_prog_load().
1610 		 * Hence, sysctl_optmem_max is not checked.
1611 		 */
1612 		if ((sk->sk_type != SOCK_STREAM &&
1613 		     sk->sk_type != SOCK_DGRAM) ||
1614 		    (sk->sk_protocol != IPPROTO_UDP &&
1615 		     sk->sk_protocol != IPPROTO_TCP) ||
1616 		    (sk->sk_family != AF_INET &&
1617 		     sk->sk_family != AF_INET6)) {
1618 			err = -ENOTSUPP;
1619 			goto err_prog_put;
1620 		}
1621 	} else {
1622 		/* BPF_PROG_TYPE_SOCKET_FILTER */
1623 		if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max)) {
1624 			err = -ENOMEM;
1625 			goto err_prog_put;
1626 		}
1627 	}
1628 
1629 	err = reuseport_attach_prog(sk, prog);
1630 err_prog_put:
1631 	if (err)
1632 		bpf_prog_put(prog);
1633 
1634 	return err;
1635 }
1636 
sk_reuseport_prog_free(struct bpf_prog * prog)1637 void sk_reuseport_prog_free(struct bpf_prog *prog)
1638 {
1639 	if (!prog)
1640 		return;
1641 
1642 	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
1643 		bpf_prog_put(prog);
1644 	else
1645 		bpf_prog_destroy(prog);
1646 }
1647 
1648 struct bpf_scratchpad {
1649 	union {
1650 		__be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1651 		u8     buff[MAX_BPF_STACK];
1652 	};
1653 };
1654 
1655 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1656 
__bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1657 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1658 					  unsigned int write_len)
1659 {
1660 #ifdef CONFIG_DEBUG_NET
1661 	/* Avoid a splat in pskb_may_pull_reason() */
1662 	if (write_len > INT_MAX)
1663 		return -EINVAL;
1664 #endif
1665 	return skb_ensure_writable(skb, write_len);
1666 }
1667 
bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1668 static inline int bpf_try_make_writable(struct sk_buff *skb,
1669 					unsigned int write_len)
1670 {
1671 	int err = __bpf_try_make_writable(skb, write_len);
1672 
1673 	bpf_compute_data_pointers(skb);
1674 	return err;
1675 }
1676 
bpf_try_make_head_writable(struct sk_buff * skb)1677 static int bpf_try_make_head_writable(struct sk_buff *skb)
1678 {
1679 	return bpf_try_make_writable(skb, skb_headlen(skb));
1680 }
1681 
bpf_push_mac_rcsum(struct sk_buff * skb)1682 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1683 {
1684 	if (skb_at_tc_ingress(skb))
1685 		skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1686 }
1687 
bpf_pull_mac_rcsum(struct sk_buff * skb)1688 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1689 {
1690 	if (skb_at_tc_ingress(skb))
1691 		skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1692 }
1693 
BPF_CALL_5(bpf_skb_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len,u64,flags)1694 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1695 	   const void *, from, u32, len, u64, flags)
1696 {
1697 	void *ptr;
1698 
1699 	if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1700 		return -EINVAL;
1701 	if (unlikely(offset > INT_MAX))
1702 		return -EFAULT;
1703 	if (unlikely(bpf_try_make_writable(skb, offset + len)))
1704 		return -EFAULT;
1705 
1706 	ptr = skb->data + offset;
1707 	if (flags & BPF_F_RECOMPUTE_CSUM)
1708 		__skb_postpull_rcsum(skb, ptr, len, offset);
1709 
1710 	memcpy(ptr, from, len);
1711 
1712 	if (flags & BPF_F_RECOMPUTE_CSUM)
1713 		__skb_postpush_rcsum(skb, ptr, len, offset);
1714 	if (flags & BPF_F_INVALIDATE_HASH)
1715 		skb_clear_hash(skb);
1716 
1717 	return 0;
1718 }
1719 
1720 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1721 	.func		= bpf_skb_store_bytes,
1722 	.gpl_only	= false,
1723 	.ret_type	= RET_INTEGER,
1724 	.arg1_type	= ARG_PTR_TO_CTX,
1725 	.arg2_type	= ARG_ANYTHING,
1726 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1727 	.arg4_type	= ARG_CONST_SIZE,
1728 	.arg5_type	= ARG_ANYTHING,
1729 };
1730 
__bpf_skb_store_bytes(struct sk_buff * skb,u32 offset,const void * from,u32 len,u64 flags)1731 int __bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from,
1732 			  u32 len, u64 flags)
1733 {
1734 	return ____bpf_skb_store_bytes(skb, offset, from, len, flags);
1735 }
1736 
BPF_CALL_4(bpf_skb_load_bytes,const struct sk_buff *,skb,u32,offset,void *,to,u32,len)1737 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1738 	   void *, to, u32, len)
1739 {
1740 	void *ptr;
1741 
1742 	if (unlikely(offset > INT_MAX))
1743 		goto err_clear;
1744 
1745 	ptr = skb_header_pointer(skb, offset, len, to);
1746 	if (unlikely(!ptr))
1747 		goto err_clear;
1748 	if (ptr != to)
1749 		memcpy(to, ptr, len);
1750 
1751 	return 0;
1752 err_clear:
1753 	memset(to, 0, len);
1754 	return -EFAULT;
1755 }
1756 
1757 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1758 	.func		= bpf_skb_load_bytes,
1759 	.gpl_only	= false,
1760 	.ret_type	= RET_INTEGER,
1761 	.arg1_type	= ARG_PTR_TO_CTX,
1762 	.arg2_type	= ARG_ANYTHING,
1763 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1764 	.arg4_type	= ARG_CONST_SIZE,
1765 };
1766 
__bpf_skb_load_bytes(const struct sk_buff * skb,u32 offset,void * to,u32 len)1767 int __bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
1768 {
1769 	return ____bpf_skb_load_bytes(skb, offset, to, len);
1770 }
1771 
BPF_CALL_4(bpf_flow_dissector_load_bytes,const struct bpf_flow_dissector *,ctx,u32,offset,void *,to,u32,len)1772 BPF_CALL_4(bpf_flow_dissector_load_bytes,
1773 	   const struct bpf_flow_dissector *, ctx, u32, offset,
1774 	   void *, to, u32, len)
1775 {
1776 	void *ptr;
1777 
1778 	if (unlikely(offset > 0xffff))
1779 		goto err_clear;
1780 
1781 	if (unlikely(!ctx->skb))
1782 		goto err_clear;
1783 
1784 	ptr = skb_header_pointer(ctx->skb, offset, len, to);
1785 	if (unlikely(!ptr))
1786 		goto err_clear;
1787 	if (ptr != to)
1788 		memcpy(to, ptr, len);
1789 
1790 	return 0;
1791 err_clear:
1792 	memset(to, 0, len);
1793 	return -EFAULT;
1794 }
1795 
1796 static const struct bpf_func_proto bpf_flow_dissector_load_bytes_proto = {
1797 	.func		= bpf_flow_dissector_load_bytes,
1798 	.gpl_only	= false,
1799 	.ret_type	= RET_INTEGER,
1800 	.arg1_type	= ARG_PTR_TO_CTX,
1801 	.arg2_type	= ARG_ANYTHING,
1802 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1803 	.arg4_type	= ARG_CONST_SIZE,
1804 };
1805 
BPF_CALL_5(bpf_skb_load_bytes_relative,const struct sk_buff *,skb,u32,offset,void *,to,u32,len,u32,start_header)1806 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
1807 	   u32, offset, void *, to, u32, len, u32, start_header)
1808 {
1809 	u8 *end = skb_tail_pointer(skb);
1810 	u8 *start, *ptr;
1811 
1812 	if (unlikely(offset > 0xffff))
1813 		goto err_clear;
1814 
1815 	switch (start_header) {
1816 	case BPF_HDR_START_MAC:
1817 		if (unlikely(!skb_mac_header_was_set(skb)))
1818 			goto err_clear;
1819 		start = skb_mac_header(skb);
1820 		break;
1821 	case BPF_HDR_START_NET:
1822 		start = skb_network_header(skb);
1823 		break;
1824 	default:
1825 		goto err_clear;
1826 	}
1827 
1828 	ptr = start + offset;
1829 
1830 	if (likely(ptr + len <= end)) {
1831 		memcpy(to, ptr, len);
1832 		return 0;
1833 	}
1834 
1835 err_clear:
1836 	memset(to, 0, len);
1837 	return -EFAULT;
1838 }
1839 
1840 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
1841 	.func		= bpf_skb_load_bytes_relative,
1842 	.gpl_only	= false,
1843 	.ret_type	= RET_INTEGER,
1844 	.arg1_type	= ARG_PTR_TO_CTX,
1845 	.arg2_type	= ARG_ANYTHING,
1846 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1847 	.arg4_type	= ARG_CONST_SIZE,
1848 	.arg5_type	= ARG_ANYTHING,
1849 };
1850 
BPF_CALL_2(bpf_skb_pull_data,struct sk_buff *,skb,u32,len)1851 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1852 {
1853 	/* Idea is the following: should the needed direct read/write
1854 	 * test fail during runtime, we can pull in more data and redo
1855 	 * again, since implicitly, we invalidate previous checks here.
1856 	 *
1857 	 * Or, since we know how much we need to make read/writeable,
1858 	 * this can be done once at the program beginning for direct
1859 	 * access case. By this we overcome limitations of only current
1860 	 * headroom being accessible.
1861 	 */
1862 	return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1863 }
1864 
1865 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1866 	.func		= bpf_skb_pull_data,
1867 	.gpl_only	= false,
1868 	.ret_type	= RET_INTEGER,
1869 	.arg1_type	= ARG_PTR_TO_CTX,
1870 	.arg2_type	= ARG_ANYTHING,
1871 };
1872 
BPF_CALL_1(bpf_sk_fullsock,struct sock *,sk)1873 BPF_CALL_1(bpf_sk_fullsock, struct sock *, sk)
1874 {
1875 	return sk_fullsock(sk) ? (unsigned long)sk : (unsigned long)NULL;
1876 }
1877 
1878 static const struct bpf_func_proto bpf_sk_fullsock_proto = {
1879 	.func		= bpf_sk_fullsock,
1880 	.gpl_only	= false,
1881 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
1882 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
1883 };
1884 
sk_skb_try_make_writable(struct sk_buff * skb,unsigned int write_len)1885 static inline int sk_skb_try_make_writable(struct sk_buff *skb,
1886 					   unsigned int write_len)
1887 {
1888 	return __bpf_try_make_writable(skb, write_len);
1889 }
1890 
BPF_CALL_2(sk_skb_pull_data,struct sk_buff *,skb,u32,len)1891 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
1892 {
1893 	/* Idea is the following: should the needed direct read/write
1894 	 * test fail during runtime, we can pull in more data and redo
1895 	 * again, since implicitly, we invalidate previous checks here.
1896 	 *
1897 	 * Or, since we know how much we need to make read/writeable,
1898 	 * this can be done once at the program beginning for direct
1899 	 * access case. By this we overcome limitations of only current
1900 	 * headroom being accessible.
1901 	 */
1902 	return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
1903 }
1904 
1905 static const struct bpf_func_proto sk_skb_pull_data_proto = {
1906 	.func		= sk_skb_pull_data,
1907 	.gpl_only	= false,
1908 	.ret_type	= RET_INTEGER,
1909 	.arg1_type	= ARG_PTR_TO_CTX,
1910 	.arg2_type	= ARG_ANYTHING,
1911 };
1912 
BPF_CALL_5(bpf_l3_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1913 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1914 	   u64, from, u64, to, u64, flags)
1915 {
1916 	__sum16 *ptr;
1917 
1918 	if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1919 		return -EINVAL;
1920 	if (unlikely(offset > 0xffff || offset & 1))
1921 		return -EFAULT;
1922 	if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1923 		return -EFAULT;
1924 
1925 	ptr = (__sum16 *)(skb->data + offset);
1926 	switch (flags & BPF_F_HDR_FIELD_MASK) {
1927 	case 0:
1928 		if (unlikely(from != 0))
1929 			return -EINVAL;
1930 
1931 		csum_replace_by_diff(ptr, to);
1932 		break;
1933 	case 2:
1934 		csum_replace2(ptr, from, to);
1935 		break;
1936 	case 4:
1937 		csum_replace4(ptr, from, to);
1938 		break;
1939 	default:
1940 		return -EINVAL;
1941 	}
1942 
1943 	return 0;
1944 }
1945 
1946 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1947 	.func		= bpf_l3_csum_replace,
1948 	.gpl_only	= false,
1949 	.ret_type	= RET_INTEGER,
1950 	.arg1_type	= ARG_PTR_TO_CTX,
1951 	.arg2_type	= ARG_ANYTHING,
1952 	.arg3_type	= ARG_ANYTHING,
1953 	.arg4_type	= ARG_ANYTHING,
1954 	.arg5_type	= ARG_ANYTHING,
1955 };
1956 
BPF_CALL_5(bpf_l4_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1957 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1958 	   u64, from, u64, to, u64, flags)
1959 {
1960 	bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1961 	bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1962 	bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1963 	__sum16 *ptr;
1964 
1965 	if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1966 			       BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1967 		return -EINVAL;
1968 	if (unlikely(offset > 0xffff || offset & 1))
1969 		return -EFAULT;
1970 	if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1971 		return -EFAULT;
1972 
1973 	ptr = (__sum16 *)(skb->data + offset);
1974 	if (is_mmzero && !do_mforce && !*ptr)
1975 		return 0;
1976 
1977 	switch (flags & BPF_F_HDR_FIELD_MASK) {
1978 	case 0:
1979 		if (unlikely(from != 0))
1980 			return -EINVAL;
1981 
1982 		inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1983 		break;
1984 	case 2:
1985 		inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1986 		break;
1987 	case 4:
1988 		inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1989 		break;
1990 	default:
1991 		return -EINVAL;
1992 	}
1993 
1994 	if (is_mmzero && !*ptr)
1995 		*ptr = CSUM_MANGLED_0;
1996 	return 0;
1997 }
1998 
1999 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
2000 	.func		= bpf_l4_csum_replace,
2001 	.gpl_only	= false,
2002 	.ret_type	= RET_INTEGER,
2003 	.arg1_type	= ARG_PTR_TO_CTX,
2004 	.arg2_type	= ARG_ANYTHING,
2005 	.arg3_type	= ARG_ANYTHING,
2006 	.arg4_type	= ARG_ANYTHING,
2007 	.arg5_type	= ARG_ANYTHING,
2008 };
2009 
BPF_CALL_5(bpf_csum_diff,__be32 *,from,u32,from_size,__be32 *,to,u32,to_size,__wsum,seed)2010 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
2011 	   __be32 *, to, u32, to_size, __wsum, seed)
2012 {
2013 	struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
2014 	u32 diff_size = from_size + to_size;
2015 	int i, j = 0;
2016 
2017 	/* This is quite flexible, some examples:
2018 	 *
2019 	 * from_size == 0, to_size > 0,  seed := csum --> pushing data
2020 	 * from_size > 0,  to_size == 0, seed := csum --> pulling data
2021 	 * from_size > 0,  to_size > 0,  seed := 0    --> diffing data
2022 	 *
2023 	 * Even for diffing, from_size and to_size don't need to be equal.
2024 	 */
2025 	if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
2026 		     diff_size > sizeof(sp->diff)))
2027 		return -EINVAL;
2028 
2029 	for (i = 0; i < from_size / sizeof(__be32); i++, j++)
2030 		sp->diff[j] = ~from[i];
2031 	for (i = 0; i <   to_size / sizeof(__be32); i++, j++)
2032 		sp->diff[j] = to[i];
2033 
2034 	return csum_partial(sp->diff, diff_size, seed);
2035 }
2036 
2037 static const struct bpf_func_proto bpf_csum_diff_proto = {
2038 	.func		= bpf_csum_diff,
2039 	.gpl_only	= false,
2040 	.pkt_access	= true,
2041 	.ret_type	= RET_INTEGER,
2042 	.arg1_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2043 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
2044 	.arg3_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2045 	.arg4_type	= ARG_CONST_SIZE_OR_ZERO,
2046 	.arg5_type	= ARG_ANYTHING,
2047 };
2048 
BPF_CALL_2(bpf_csum_update,struct sk_buff *,skb,__wsum,csum)2049 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
2050 {
2051 	/* The interface is to be used in combination with bpf_csum_diff()
2052 	 * for direct packet writes. csum rotation for alignment as well
2053 	 * as emulating csum_sub() can be done from the eBPF program.
2054 	 */
2055 	if (skb->ip_summed == CHECKSUM_COMPLETE)
2056 		return (skb->csum = csum_add(skb->csum, csum));
2057 
2058 	return -ENOTSUPP;
2059 }
2060 
2061 static const struct bpf_func_proto bpf_csum_update_proto = {
2062 	.func		= bpf_csum_update,
2063 	.gpl_only	= false,
2064 	.ret_type	= RET_INTEGER,
2065 	.arg1_type	= ARG_PTR_TO_CTX,
2066 	.arg2_type	= ARG_ANYTHING,
2067 };
2068 
BPF_CALL_2(bpf_csum_level,struct sk_buff *,skb,u64,level)2069 BPF_CALL_2(bpf_csum_level, struct sk_buff *, skb, u64, level)
2070 {
2071 	/* The interface is to be used in combination with bpf_skb_adjust_room()
2072 	 * for encap/decap of packet headers when BPF_F_ADJ_ROOM_NO_CSUM_RESET
2073 	 * is passed as flags, for example.
2074 	 */
2075 	switch (level) {
2076 	case BPF_CSUM_LEVEL_INC:
2077 		__skb_incr_checksum_unnecessary(skb);
2078 		break;
2079 	case BPF_CSUM_LEVEL_DEC:
2080 		__skb_decr_checksum_unnecessary(skb);
2081 		break;
2082 	case BPF_CSUM_LEVEL_RESET:
2083 		__skb_reset_checksum_unnecessary(skb);
2084 		break;
2085 	case BPF_CSUM_LEVEL_QUERY:
2086 		return skb->ip_summed == CHECKSUM_UNNECESSARY ?
2087 		       skb->csum_level : -EACCES;
2088 	default:
2089 		return -EINVAL;
2090 	}
2091 
2092 	return 0;
2093 }
2094 
2095 static const struct bpf_func_proto bpf_csum_level_proto = {
2096 	.func		= bpf_csum_level,
2097 	.gpl_only	= false,
2098 	.ret_type	= RET_INTEGER,
2099 	.arg1_type	= ARG_PTR_TO_CTX,
2100 	.arg2_type	= ARG_ANYTHING,
2101 };
2102 
__bpf_rx_skb(struct net_device * dev,struct sk_buff * skb)2103 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
2104 {
2105 	return dev_forward_skb_nomtu(dev, skb);
2106 }
2107 
__bpf_rx_skb_no_mac(struct net_device * dev,struct sk_buff * skb)2108 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
2109 				      struct sk_buff *skb)
2110 {
2111 	int ret = ____dev_forward_skb(dev, skb, false);
2112 
2113 	if (likely(!ret)) {
2114 		skb->dev = dev;
2115 		ret = netif_rx(skb);
2116 	}
2117 
2118 	return ret;
2119 }
2120 
__bpf_tx_skb(struct net_device * dev,struct sk_buff * skb)2121 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
2122 {
2123 	int ret;
2124 
2125 	if (dev_xmit_recursion()) {
2126 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2127 		kfree_skb(skb);
2128 		return -ENETDOWN;
2129 	}
2130 
2131 	skb->dev = dev;
2132 	skb_set_redirected_noclear(skb, skb_at_tc_ingress(skb));
2133 	skb_clear_tstamp(skb);
2134 
2135 	dev_xmit_recursion_inc();
2136 	ret = dev_queue_xmit(skb);
2137 	dev_xmit_recursion_dec();
2138 
2139 	return ret;
2140 }
2141 
__bpf_redirect_no_mac(struct sk_buff * skb,struct net_device * dev,u32 flags)2142 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
2143 				 u32 flags)
2144 {
2145 	unsigned int mlen = skb_network_offset(skb);
2146 
2147 	if (unlikely(skb->len <= mlen)) {
2148 		kfree_skb(skb);
2149 		return -ERANGE;
2150 	}
2151 
2152 	if (mlen) {
2153 		__skb_pull(skb, mlen);
2154 
2155 		/* At ingress, the mac header has already been pulled once.
2156 		 * At egress, skb_pospull_rcsum has to be done in case that
2157 		 * the skb is originated from ingress (i.e. a forwarded skb)
2158 		 * to ensure that rcsum starts at net header.
2159 		 */
2160 		if (!skb_at_tc_ingress(skb))
2161 			skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
2162 	}
2163 	skb_pop_mac_header(skb);
2164 	skb_reset_mac_len(skb);
2165 	return flags & BPF_F_INGRESS ?
2166 	       __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
2167 }
2168 
__bpf_redirect_common(struct sk_buff * skb,struct net_device * dev,u32 flags)2169 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
2170 				 u32 flags)
2171 {
2172 	/* Verify that a link layer header is carried */
2173 	if (unlikely(skb->mac_header >= skb->network_header || skb->len == 0)) {
2174 		kfree_skb(skb);
2175 		return -ERANGE;
2176 	}
2177 
2178 	bpf_push_mac_rcsum(skb);
2179 	return flags & BPF_F_INGRESS ?
2180 	       __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
2181 }
2182 
__bpf_redirect(struct sk_buff * skb,struct net_device * dev,u32 flags)2183 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
2184 			  u32 flags)
2185 {
2186 	if (dev_is_mac_header_xmit(dev))
2187 		return __bpf_redirect_common(skb, dev, flags);
2188 	else
2189 		return __bpf_redirect_no_mac(skb, dev, flags);
2190 }
2191 
2192 #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)2193 static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
2194 			    struct net_device *dev, struct bpf_nh_params *nh)
2195 {
2196 	u32 hh_len = LL_RESERVED_SPACE(dev);
2197 	const struct in6_addr *nexthop;
2198 	struct dst_entry *dst = NULL;
2199 	struct neighbour *neigh;
2200 
2201 	if (dev_xmit_recursion()) {
2202 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2203 		goto out_drop;
2204 	}
2205 
2206 	skb->dev = dev;
2207 	skb_clear_tstamp(skb);
2208 
2209 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2210 		skb = skb_expand_head(skb, hh_len);
2211 		if (!skb)
2212 			return -ENOMEM;
2213 	}
2214 
2215 	rcu_read_lock();
2216 	if (!nh) {
2217 		dst = skb_dst(skb);
2218 		nexthop = rt6_nexthop(container_of(dst, struct rt6_info, dst),
2219 				      &ipv6_hdr(skb)->daddr);
2220 	} else {
2221 		nexthop = &nh->ipv6_nh;
2222 	}
2223 	neigh = ip_neigh_gw6(dev, nexthop);
2224 	if (likely(!IS_ERR(neigh))) {
2225 		int ret;
2226 
2227 		sock_confirm_neigh(skb, neigh);
2228 		local_bh_disable();
2229 		dev_xmit_recursion_inc();
2230 		ret = neigh_output(neigh, skb, false);
2231 		dev_xmit_recursion_dec();
2232 		local_bh_enable();
2233 		rcu_read_unlock();
2234 		return ret;
2235 	}
2236 	rcu_read_unlock_bh();
2237 	if (dst)
2238 		IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
2239 out_drop:
2240 	kfree_skb(skb);
2241 	return -ENETDOWN;
2242 }
2243 
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2244 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2245 				   struct bpf_nh_params *nh)
2246 {
2247 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
2248 	struct net *net = dev_net(dev);
2249 	int err, ret = NET_XMIT_DROP;
2250 
2251 	if (!nh) {
2252 		struct dst_entry *dst;
2253 		struct flowi6 fl6 = {
2254 			.flowi6_flags = FLOWI_FLAG_ANYSRC,
2255 			.flowi6_mark  = skb->mark,
2256 			.flowlabel    = ip6_flowinfo(ip6h),
2257 			.flowi6_oif   = dev->ifindex,
2258 			.flowi6_proto = ip6h->nexthdr,
2259 			.daddr	      = ip6h->daddr,
2260 			.saddr	      = ip6h->saddr,
2261 		};
2262 
2263 		dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &fl6, NULL);
2264 		if (IS_ERR(dst))
2265 			goto out_drop;
2266 
2267 		skb_dst_set(skb, dst);
2268 	} else if (nh->nh_family != AF_INET6) {
2269 		goto out_drop;
2270 	}
2271 
2272 	err = bpf_out_neigh_v6(net, skb, dev, nh);
2273 	if (unlikely(net_xmit_eval(err)))
2274 		dev->stats.tx_errors++;
2275 	else
2276 		ret = NET_XMIT_SUCCESS;
2277 	goto out_xmit;
2278 out_drop:
2279 	dev->stats.tx_errors++;
2280 	kfree_skb(skb);
2281 out_xmit:
2282 	return ret;
2283 }
2284 #else
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2285 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2286 				   struct bpf_nh_params *nh)
2287 {
2288 	kfree_skb(skb);
2289 	return NET_XMIT_DROP;
2290 }
2291 #endif /* CONFIG_IPV6 */
2292 
2293 #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)2294 static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
2295 			    struct net_device *dev, struct bpf_nh_params *nh)
2296 {
2297 	u32 hh_len = LL_RESERVED_SPACE(dev);
2298 	struct neighbour *neigh;
2299 	bool is_v6gw = false;
2300 
2301 	if (dev_xmit_recursion()) {
2302 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2303 		goto out_drop;
2304 	}
2305 
2306 	skb->dev = dev;
2307 	skb_clear_tstamp(skb);
2308 
2309 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2310 		skb = skb_expand_head(skb, hh_len);
2311 		if (!skb)
2312 			return -ENOMEM;
2313 	}
2314 
2315 	rcu_read_lock();
2316 	if (!nh) {
2317 		struct dst_entry *dst = skb_dst(skb);
2318 		struct rtable *rt = container_of(dst, struct rtable, dst);
2319 
2320 		neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
2321 	} else if (nh->nh_family == AF_INET6) {
2322 		neigh = ip_neigh_gw6(dev, &nh->ipv6_nh);
2323 		is_v6gw = true;
2324 	} else if (nh->nh_family == AF_INET) {
2325 		neigh = ip_neigh_gw4(dev, nh->ipv4_nh);
2326 	} else {
2327 		rcu_read_unlock();
2328 		goto out_drop;
2329 	}
2330 
2331 	if (likely(!IS_ERR(neigh))) {
2332 		int ret;
2333 
2334 		sock_confirm_neigh(skb, neigh);
2335 		local_bh_disable();
2336 		dev_xmit_recursion_inc();
2337 		ret = neigh_output(neigh, skb, is_v6gw);
2338 		dev_xmit_recursion_dec();
2339 		local_bh_enable();
2340 		rcu_read_unlock();
2341 		return ret;
2342 	}
2343 	rcu_read_unlock();
2344 out_drop:
2345 	kfree_skb(skb);
2346 	return -ENETDOWN;
2347 }
2348 
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2349 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2350 				   struct bpf_nh_params *nh)
2351 {
2352 	const struct iphdr *ip4h = ip_hdr(skb);
2353 	struct net *net = dev_net(dev);
2354 	int err, ret = NET_XMIT_DROP;
2355 
2356 	if (!nh) {
2357 		struct flowi4 fl4 = {
2358 			.flowi4_flags = FLOWI_FLAG_ANYSRC,
2359 			.flowi4_mark  = skb->mark,
2360 			.flowi4_tos   = RT_TOS(ip4h->tos),
2361 			.flowi4_oif   = dev->ifindex,
2362 			.flowi4_proto = ip4h->protocol,
2363 			.daddr	      = ip4h->daddr,
2364 			.saddr	      = ip4h->saddr,
2365 		};
2366 		struct rtable *rt;
2367 
2368 		rt = ip_route_output_flow(net, &fl4, NULL);
2369 		if (IS_ERR(rt))
2370 			goto out_drop;
2371 		if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
2372 			ip_rt_put(rt);
2373 			goto out_drop;
2374 		}
2375 
2376 		skb_dst_set(skb, &rt->dst);
2377 	}
2378 
2379 	err = bpf_out_neigh_v4(net, skb, dev, nh);
2380 	if (unlikely(net_xmit_eval(err)))
2381 		dev->stats.tx_errors++;
2382 	else
2383 		ret = NET_XMIT_SUCCESS;
2384 	goto out_xmit;
2385 out_drop:
2386 	dev->stats.tx_errors++;
2387 	kfree_skb(skb);
2388 out_xmit:
2389 	return ret;
2390 }
2391 #else
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2392 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2393 				   struct bpf_nh_params *nh)
2394 {
2395 	kfree_skb(skb);
2396 	return NET_XMIT_DROP;
2397 }
2398 #endif /* CONFIG_INET */
2399 
__bpf_redirect_neigh(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2400 static int __bpf_redirect_neigh(struct sk_buff *skb, struct net_device *dev,
2401 				struct bpf_nh_params *nh)
2402 {
2403 	struct ethhdr *ethh = eth_hdr(skb);
2404 
2405 	if (unlikely(skb->mac_header >= skb->network_header))
2406 		goto out;
2407 	bpf_push_mac_rcsum(skb);
2408 	if (is_multicast_ether_addr(ethh->h_dest))
2409 		goto out;
2410 
2411 	skb_pull(skb, sizeof(*ethh));
2412 	skb_unset_mac_header(skb);
2413 	skb_reset_network_header(skb);
2414 
2415 	if (skb->protocol == htons(ETH_P_IP))
2416 		return __bpf_redirect_neigh_v4(skb, dev, nh);
2417 	else if (skb->protocol == htons(ETH_P_IPV6))
2418 		return __bpf_redirect_neigh_v6(skb, dev, nh);
2419 out:
2420 	kfree_skb(skb);
2421 	return -ENOTSUPP;
2422 }
2423 
2424 /* Internal, non-exposed redirect flags. */
2425 enum {
2426 	BPF_F_NEIGH	= (1ULL << 1),
2427 	BPF_F_PEER	= (1ULL << 2),
2428 	BPF_F_NEXTHOP	= (1ULL << 3),
2429 #define BPF_F_REDIRECT_INTERNAL	(BPF_F_NEIGH | BPF_F_PEER | BPF_F_NEXTHOP)
2430 };
2431 
BPF_CALL_3(bpf_clone_redirect,struct sk_buff *,skb,u32,ifindex,u64,flags)2432 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
2433 {
2434 	struct net_device *dev;
2435 	struct sk_buff *clone;
2436 	int ret;
2437 
2438 	if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2439 		return -EINVAL;
2440 
2441 	dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
2442 	if (unlikely(!dev))
2443 		return -EINVAL;
2444 
2445 	clone = skb_clone(skb, GFP_ATOMIC);
2446 	if (unlikely(!clone))
2447 		return -ENOMEM;
2448 
2449 	/* For direct write, we need to keep the invariant that the skbs
2450 	 * we're dealing with need to be uncloned. Should uncloning fail
2451 	 * here, we need to free the just generated clone to unclone once
2452 	 * again.
2453 	 */
2454 	ret = bpf_try_make_head_writable(skb);
2455 	if (unlikely(ret)) {
2456 		kfree_skb(clone);
2457 		return -ENOMEM;
2458 	}
2459 
2460 	return __bpf_redirect(clone, dev, flags);
2461 }
2462 
2463 static const struct bpf_func_proto bpf_clone_redirect_proto = {
2464 	.func           = bpf_clone_redirect,
2465 	.gpl_only       = false,
2466 	.ret_type       = RET_INTEGER,
2467 	.arg1_type      = ARG_PTR_TO_CTX,
2468 	.arg2_type      = ARG_ANYTHING,
2469 	.arg3_type      = ARG_ANYTHING,
2470 };
2471 
2472 DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
2473 EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info);
2474 
skb_do_redirect(struct sk_buff * skb)2475 int skb_do_redirect(struct sk_buff *skb)
2476 {
2477 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2478 	struct net *net = dev_net(skb->dev);
2479 	struct net_device *dev;
2480 	u32 flags = ri->flags;
2481 
2482 	dev = dev_get_by_index_rcu(net, ri->tgt_index);
2483 	ri->tgt_index = 0;
2484 	ri->flags = 0;
2485 	if (unlikely(!dev))
2486 		goto out_drop;
2487 	if (flags & BPF_F_PEER) {
2488 		const struct net_device_ops *ops = dev->netdev_ops;
2489 
2490 		if (unlikely(!ops->ndo_get_peer_dev ||
2491 			     !skb_at_tc_ingress(skb)))
2492 			goto out_drop;
2493 		dev = ops->ndo_get_peer_dev(dev);
2494 		if (unlikely(!dev ||
2495 			     !(dev->flags & IFF_UP) ||
2496 			     net_eq(net, dev_net(dev))))
2497 			goto out_drop;
2498 		skb->dev = dev;
2499 		dev_sw_netstats_rx_add(dev, skb->len);
2500 		return -EAGAIN;
2501 	}
2502 	return flags & BPF_F_NEIGH ?
2503 	       __bpf_redirect_neigh(skb, dev, flags & BPF_F_NEXTHOP ?
2504 				    &ri->nh : NULL) :
2505 	       __bpf_redirect(skb, dev, flags);
2506 out_drop:
2507 	kfree_skb(skb);
2508 	return -EINVAL;
2509 }
2510 
BPF_CALL_2(bpf_redirect,u32,ifindex,u64,flags)2511 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
2512 {
2513 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2514 
2515 	if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2516 		return TC_ACT_SHOT;
2517 
2518 	ri->flags = flags;
2519 	ri->tgt_index = ifindex;
2520 
2521 	return TC_ACT_REDIRECT;
2522 }
2523 
2524 static const struct bpf_func_proto bpf_redirect_proto = {
2525 	.func           = bpf_redirect,
2526 	.gpl_only       = false,
2527 	.ret_type       = RET_INTEGER,
2528 	.arg1_type      = ARG_ANYTHING,
2529 	.arg2_type      = ARG_ANYTHING,
2530 };
2531 
BPF_CALL_2(bpf_redirect_peer,u32,ifindex,u64,flags)2532 BPF_CALL_2(bpf_redirect_peer, u32, ifindex, u64, flags)
2533 {
2534 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2535 
2536 	if (unlikely(flags))
2537 		return TC_ACT_SHOT;
2538 
2539 	ri->flags = BPF_F_PEER;
2540 	ri->tgt_index = ifindex;
2541 
2542 	return TC_ACT_REDIRECT;
2543 }
2544 
2545 static const struct bpf_func_proto bpf_redirect_peer_proto = {
2546 	.func           = bpf_redirect_peer,
2547 	.gpl_only       = false,
2548 	.ret_type       = RET_INTEGER,
2549 	.arg1_type      = ARG_ANYTHING,
2550 	.arg2_type      = ARG_ANYTHING,
2551 };
2552 
BPF_CALL_4(bpf_redirect_neigh,u32,ifindex,struct bpf_redir_neigh *,params,int,plen,u64,flags)2553 BPF_CALL_4(bpf_redirect_neigh, u32, ifindex, struct bpf_redir_neigh *, params,
2554 	   int, plen, u64, flags)
2555 {
2556 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2557 
2558 	if (unlikely((plen && plen < sizeof(*params)) || flags))
2559 		return TC_ACT_SHOT;
2560 
2561 	ri->flags = BPF_F_NEIGH | (plen ? BPF_F_NEXTHOP : 0);
2562 	ri->tgt_index = ifindex;
2563 
2564 	BUILD_BUG_ON(sizeof(struct bpf_redir_neigh) != sizeof(struct bpf_nh_params));
2565 	if (plen)
2566 		memcpy(&ri->nh, params, sizeof(ri->nh));
2567 
2568 	return TC_ACT_REDIRECT;
2569 }
2570 
2571 static const struct bpf_func_proto bpf_redirect_neigh_proto = {
2572 	.func		= bpf_redirect_neigh,
2573 	.gpl_only	= false,
2574 	.ret_type	= RET_INTEGER,
2575 	.arg1_type	= ARG_ANYTHING,
2576 	.arg2_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2577 	.arg3_type      = ARG_CONST_SIZE_OR_ZERO,
2578 	.arg4_type	= ARG_ANYTHING,
2579 };
2580 
BPF_CALL_2(bpf_msg_apply_bytes,struct sk_msg *,msg,u32,bytes)2581 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes)
2582 {
2583 	msg->apply_bytes = bytes;
2584 	return 0;
2585 }
2586 
2587 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
2588 	.func           = bpf_msg_apply_bytes,
2589 	.gpl_only       = false,
2590 	.ret_type       = RET_INTEGER,
2591 	.arg1_type	= ARG_PTR_TO_CTX,
2592 	.arg2_type      = ARG_ANYTHING,
2593 };
2594 
BPF_CALL_2(bpf_msg_cork_bytes,struct sk_msg *,msg,u32,bytes)2595 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
2596 {
2597 	msg->cork_bytes = bytes;
2598 	return 0;
2599 }
2600 
sk_msg_reset_curr(struct sk_msg * msg)2601 static void sk_msg_reset_curr(struct sk_msg *msg)
2602 {
2603 	u32 i = msg->sg.start;
2604 	u32 len = 0;
2605 
2606 	do {
2607 		len += sk_msg_elem(msg, i)->length;
2608 		sk_msg_iter_var_next(i);
2609 		if (len >= msg->sg.size)
2610 			break;
2611 	} while (i != msg->sg.end);
2612 
2613 	msg->sg.curr = i;
2614 	msg->sg.copybreak = 0;
2615 }
2616 
2617 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
2618 	.func           = bpf_msg_cork_bytes,
2619 	.gpl_only       = false,
2620 	.ret_type       = RET_INTEGER,
2621 	.arg1_type	= ARG_PTR_TO_CTX,
2622 	.arg2_type      = ARG_ANYTHING,
2623 };
2624 
BPF_CALL_4(bpf_msg_pull_data,struct sk_msg *,msg,u32,start,u32,end,u64,flags)2625 BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
2626 	   u32, end, u64, flags)
2627 {
2628 	u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start;
2629 	u32 first_sge, last_sge, i, shift, bytes_sg_total;
2630 	struct scatterlist *sge;
2631 	u8 *raw, *to, *from;
2632 	struct page *page;
2633 
2634 	if (unlikely(flags || end <= start))
2635 		return -EINVAL;
2636 
2637 	/* First find the starting scatterlist element */
2638 	i = msg->sg.start;
2639 	do {
2640 		offset += len;
2641 		len = sk_msg_elem(msg, i)->length;
2642 		if (start < offset + len)
2643 			break;
2644 		sk_msg_iter_var_next(i);
2645 	} while (i != msg->sg.end);
2646 
2647 	if (unlikely(start >= offset + len))
2648 		return -EINVAL;
2649 
2650 	first_sge = i;
2651 	/* The start may point into the sg element so we need to also
2652 	 * account for the headroom.
2653 	 */
2654 	bytes_sg_total = start - offset + bytes;
2655 	if (!test_bit(i, msg->sg.copy) && bytes_sg_total <= len)
2656 		goto out;
2657 
2658 	/* At this point we need to linearize multiple scatterlist
2659 	 * elements or a single shared page. Either way we need to
2660 	 * copy into a linear buffer exclusively owned by BPF. Then
2661 	 * place the buffer in the scatterlist and fixup the original
2662 	 * entries by removing the entries now in the linear buffer
2663 	 * and shifting the remaining entries. For now we do not try
2664 	 * to copy partial entries to avoid complexity of running out
2665 	 * of sg_entry slots. The downside is reading a single byte
2666 	 * will copy the entire sg entry.
2667 	 */
2668 	do {
2669 		copy += sk_msg_elem(msg, i)->length;
2670 		sk_msg_iter_var_next(i);
2671 		if (bytes_sg_total <= copy)
2672 			break;
2673 	} while (i != msg->sg.end);
2674 	last_sge = i;
2675 
2676 	if (unlikely(bytes_sg_total > copy))
2677 		return -EINVAL;
2678 
2679 	page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2680 			   get_order(copy));
2681 	if (unlikely(!page))
2682 		return -ENOMEM;
2683 
2684 	raw = page_address(page);
2685 	i = first_sge;
2686 	do {
2687 		sge = sk_msg_elem(msg, i);
2688 		from = sg_virt(sge);
2689 		len = sge->length;
2690 		to = raw + poffset;
2691 
2692 		memcpy(to, from, len);
2693 		poffset += len;
2694 		sge->length = 0;
2695 		put_page(sg_page(sge));
2696 
2697 		sk_msg_iter_var_next(i);
2698 	} while (i != last_sge);
2699 
2700 	sg_set_page(&msg->sg.data[first_sge], page, copy, 0);
2701 
2702 	/* To repair sg ring we need to shift entries. If we only
2703 	 * had a single entry though we can just replace it and
2704 	 * be done. Otherwise walk the ring and shift the entries.
2705 	 */
2706 	WARN_ON_ONCE(last_sge == first_sge);
2707 	shift = last_sge > first_sge ?
2708 		last_sge - first_sge - 1 :
2709 		NR_MSG_FRAG_IDS - first_sge + last_sge - 1;
2710 	if (!shift)
2711 		goto out;
2712 
2713 	i = first_sge;
2714 	sk_msg_iter_var_next(i);
2715 	do {
2716 		u32 move_from;
2717 
2718 		if (i + shift >= NR_MSG_FRAG_IDS)
2719 			move_from = i + shift - NR_MSG_FRAG_IDS;
2720 		else
2721 			move_from = i + shift;
2722 		if (move_from == msg->sg.end)
2723 			break;
2724 
2725 		msg->sg.data[i] = msg->sg.data[move_from];
2726 		msg->sg.data[move_from].length = 0;
2727 		msg->sg.data[move_from].page_link = 0;
2728 		msg->sg.data[move_from].offset = 0;
2729 		sk_msg_iter_var_next(i);
2730 	} while (1);
2731 
2732 	msg->sg.end = msg->sg.end - shift > msg->sg.end ?
2733 		      msg->sg.end - shift + NR_MSG_FRAG_IDS :
2734 		      msg->sg.end - shift;
2735 out:
2736 	sk_msg_reset_curr(msg);
2737 	msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
2738 	msg->data_end = msg->data + bytes;
2739 	return 0;
2740 }
2741 
2742 static const struct bpf_func_proto bpf_msg_pull_data_proto = {
2743 	.func		= bpf_msg_pull_data,
2744 	.gpl_only	= false,
2745 	.ret_type	= RET_INTEGER,
2746 	.arg1_type	= ARG_PTR_TO_CTX,
2747 	.arg2_type	= ARG_ANYTHING,
2748 	.arg3_type	= ARG_ANYTHING,
2749 	.arg4_type	= ARG_ANYTHING,
2750 };
2751 
BPF_CALL_4(bpf_msg_push_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2752 BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
2753 	   u32, len, u64, flags)
2754 {
2755 	struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge;
2756 	u32 new, i = 0, l = 0, space, copy = 0, offset = 0;
2757 	u8 *raw, *to, *from;
2758 	struct page *page;
2759 
2760 	if (unlikely(flags))
2761 		return -EINVAL;
2762 
2763 	if (unlikely(len == 0))
2764 		return 0;
2765 
2766 	/* First find the starting scatterlist element */
2767 	i = msg->sg.start;
2768 	do {
2769 		offset += l;
2770 		l = sk_msg_elem(msg, i)->length;
2771 
2772 		if (start < offset + l)
2773 			break;
2774 		sk_msg_iter_var_next(i);
2775 	} while (i != msg->sg.end);
2776 
2777 	if (start >= offset + l)
2778 		return -EINVAL;
2779 
2780 	space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2781 
2782 	/* If no space available will fallback to copy, we need at
2783 	 * least one scatterlist elem available to push data into
2784 	 * when start aligns to the beginning of an element or two
2785 	 * when it falls inside an element. We handle the start equals
2786 	 * offset case because its the common case for inserting a
2787 	 * header.
2788 	 */
2789 	if (!space || (space == 1 && start != offset))
2790 		copy = msg->sg.data[i].length;
2791 
2792 	page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2793 			   get_order(copy + len));
2794 	if (unlikely(!page))
2795 		return -ENOMEM;
2796 
2797 	if (copy) {
2798 		int front, back;
2799 
2800 		raw = page_address(page);
2801 
2802 		psge = sk_msg_elem(msg, i);
2803 		front = start - offset;
2804 		back = psge->length - front;
2805 		from = sg_virt(psge);
2806 
2807 		if (front)
2808 			memcpy(raw, from, front);
2809 
2810 		if (back) {
2811 			from += front;
2812 			to = raw + front + len;
2813 
2814 			memcpy(to, from, back);
2815 		}
2816 
2817 		put_page(sg_page(psge));
2818 	} else if (start - offset) {
2819 		psge = sk_msg_elem(msg, i);
2820 		rsge = sk_msg_elem_cpy(msg, i);
2821 
2822 		psge->length = start - offset;
2823 		rsge.length -= psge->length;
2824 		rsge.offset += start;
2825 
2826 		sk_msg_iter_var_next(i);
2827 		sg_unmark_end(psge);
2828 		sg_unmark_end(&rsge);
2829 		sk_msg_iter_next(msg, end);
2830 	}
2831 
2832 	/* Slot(s) to place newly allocated data */
2833 	new = i;
2834 
2835 	/* Shift one or two slots as needed */
2836 	if (!copy) {
2837 		sge = sk_msg_elem_cpy(msg, i);
2838 
2839 		sk_msg_iter_var_next(i);
2840 		sg_unmark_end(&sge);
2841 		sk_msg_iter_next(msg, end);
2842 
2843 		nsge = sk_msg_elem_cpy(msg, i);
2844 		if (rsge.length) {
2845 			sk_msg_iter_var_next(i);
2846 			nnsge = sk_msg_elem_cpy(msg, i);
2847 		}
2848 
2849 		while (i != msg->sg.end) {
2850 			msg->sg.data[i] = sge;
2851 			sge = nsge;
2852 			sk_msg_iter_var_next(i);
2853 			if (rsge.length) {
2854 				nsge = nnsge;
2855 				nnsge = sk_msg_elem_cpy(msg, i);
2856 			} else {
2857 				nsge = sk_msg_elem_cpy(msg, i);
2858 			}
2859 		}
2860 	}
2861 
2862 	/* Place newly allocated data buffer */
2863 	sk_mem_charge(msg->sk, len);
2864 	msg->sg.size += len;
2865 	__clear_bit(new, msg->sg.copy);
2866 	sg_set_page(&msg->sg.data[new], page, len + copy, 0);
2867 	if (rsge.length) {
2868 		get_page(sg_page(&rsge));
2869 		sk_msg_iter_var_next(new);
2870 		msg->sg.data[new] = rsge;
2871 	}
2872 
2873 	sk_msg_reset_curr(msg);
2874 	sk_msg_compute_data_pointers(msg);
2875 	return 0;
2876 }
2877 
2878 static const struct bpf_func_proto bpf_msg_push_data_proto = {
2879 	.func		= bpf_msg_push_data,
2880 	.gpl_only	= false,
2881 	.ret_type	= RET_INTEGER,
2882 	.arg1_type	= ARG_PTR_TO_CTX,
2883 	.arg2_type	= ARG_ANYTHING,
2884 	.arg3_type	= ARG_ANYTHING,
2885 	.arg4_type	= ARG_ANYTHING,
2886 };
2887 
sk_msg_shift_left(struct sk_msg * msg,int i)2888 static void sk_msg_shift_left(struct sk_msg *msg, int i)
2889 {
2890 	int prev;
2891 
2892 	do {
2893 		prev = i;
2894 		sk_msg_iter_var_next(i);
2895 		msg->sg.data[prev] = msg->sg.data[i];
2896 	} while (i != msg->sg.end);
2897 
2898 	sk_msg_iter_prev(msg, end);
2899 }
2900 
sk_msg_shift_right(struct sk_msg * msg,int i)2901 static void sk_msg_shift_right(struct sk_msg *msg, int i)
2902 {
2903 	struct scatterlist tmp, sge;
2904 
2905 	sk_msg_iter_next(msg, end);
2906 	sge = sk_msg_elem_cpy(msg, i);
2907 	sk_msg_iter_var_next(i);
2908 	tmp = sk_msg_elem_cpy(msg, i);
2909 
2910 	while (i != msg->sg.end) {
2911 		msg->sg.data[i] = sge;
2912 		sk_msg_iter_var_next(i);
2913 		sge = tmp;
2914 		tmp = sk_msg_elem_cpy(msg, i);
2915 	}
2916 }
2917 
BPF_CALL_4(bpf_msg_pop_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2918 BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
2919 	   u32, len, u64, flags)
2920 {
2921 	u32 i = 0, l = 0, space, offset = 0;
2922 	u64 last = start + len;
2923 	int pop;
2924 
2925 	if (unlikely(flags))
2926 		return -EINVAL;
2927 
2928 	/* First find the starting scatterlist element */
2929 	i = msg->sg.start;
2930 	do {
2931 		offset += l;
2932 		l = sk_msg_elem(msg, i)->length;
2933 
2934 		if (start < offset + l)
2935 			break;
2936 		sk_msg_iter_var_next(i);
2937 	} while (i != msg->sg.end);
2938 
2939 	/* Bounds checks: start and pop must be inside message */
2940 	if (start >= offset + l || last >= msg->sg.size)
2941 		return -EINVAL;
2942 
2943 	space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2944 
2945 	pop = len;
2946 	/* --------------| offset
2947 	 * -| start      |-------- len -------|
2948 	 *
2949 	 *  |----- a ----|-------- pop -------|----- b ----|
2950 	 *  |______________________________________________| length
2951 	 *
2952 	 *
2953 	 * a:   region at front of scatter element to save
2954 	 * b:   region at back of scatter element to save when length > A + pop
2955 	 * pop: region to pop from element, same as input 'pop' here will be
2956 	 *      decremented below per iteration.
2957 	 *
2958 	 * Two top-level cases to handle when start != offset, first B is non
2959 	 * zero and second B is zero corresponding to when a pop includes more
2960 	 * than one element.
2961 	 *
2962 	 * Then if B is non-zero AND there is no space allocate space and
2963 	 * compact A, B regions into page. If there is space shift ring to
2964 	 * the rigth free'ing the next element in ring to place B, leaving
2965 	 * A untouched except to reduce length.
2966 	 */
2967 	if (start != offset) {
2968 		struct scatterlist *nsge, *sge = sk_msg_elem(msg, i);
2969 		int a = start;
2970 		int b = sge->length - pop - a;
2971 
2972 		sk_msg_iter_var_next(i);
2973 
2974 		if (pop < sge->length - a) {
2975 			if (space) {
2976 				sge->length = a;
2977 				sk_msg_shift_right(msg, i);
2978 				nsge = sk_msg_elem(msg, i);
2979 				get_page(sg_page(sge));
2980 				sg_set_page(nsge,
2981 					    sg_page(sge),
2982 					    b, sge->offset + pop + a);
2983 			} else {
2984 				struct page *page, *orig;
2985 				u8 *to, *from;
2986 
2987 				page = alloc_pages(__GFP_NOWARN |
2988 						   __GFP_COMP   | GFP_ATOMIC,
2989 						   get_order(a + b));
2990 				if (unlikely(!page))
2991 					return -ENOMEM;
2992 
2993 				sge->length = a;
2994 				orig = sg_page(sge);
2995 				from = sg_virt(sge);
2996 				to = page_address(page);
2997 				memcpy(to, from, a);
2998 				memcpy(to + a, from + a + pop, b);
2999 				sg_set_page(sge, page, a + b, 0);
3000 				put_page(orig);
3001 			}
3002 			pop = 0;
3003 		} else if (pop >= sge->length - a) {
3004 			pop -= (sge->length - a);
3005 			sge->length = a;
3006 		}
3007 	}
3008 
3009 	/* From above the current layout _must_ be as follows,
3010 	 *
3011 	 * -| offset
3012 	 * -| start
3013 	 *
3014 	 *  |---- pop ---|---------------- b ------------|
3015 	 *  |____________________________________________| length
3016 	 *
3017 	 * Offset and start of the current msg elem are equal because in the
3018 	 * previous case we handled offset != start and either consumed the
3019 	 * entire element and advanced to the next element OR pop == 0.
3020 	 *
3021 	 * Two cases to handle here are first pop is less than the length
3022 	 * leaving some remainder b above. Simply adjust the element's layout
3023 	 * in this case. Or pop >= length of the element so that b = 0. In this
3024 	 * case advance to next element decrementing pop.
3025 	 */
3026 	while (pop) {
3027 		struct scatterlist *sge = sk_msg_elem(msg, i);
3028 
3029 		if (pop < sge->length) {
3030 			sge->length -= pop;
3031 			sge->offset += pop;
3032 			pop = 0;
3033 		} else {
3034 			pop -= sge->length;
3035 			sk_msg_shift_left(msg, i);
3036 		}
3037 		sk_msg_iter_var_next(i);
3038 	}
3039 
3040 	sk_mem_uncharge(msg->sk, len - pop);
3041 	msg->sg.size -= (len - pop);
3042 	sk_msg_reset_curr(msg);
3043 	sk_msg_compute_data_pointers(msg);
3044 	return 0;
3045 }
3046 
3047 static const struct bpf_func_proto bpf_msg_pop_data_proto = {
3048 	.func		= bpf_msg_pop_data,
3049 	.gpl_only	= false,
3050 	.ret_type	= RET_INTEGER,
3051 	.arg1_type	= ARG_PTR_TO_CTX,
3052 	.arg2_type	= ARG_ANYTHING,
3053 	.arg3_type	= ARG_ANYTHING,
3054 	.arg4_type	= ARG_ANYTHING,
3055 };
3056 
3057 #ifdef CONFIG_CGROUP_NET_CLASSID
BPF_CALL_0(bpf_get_cgroup_classid_curr)3058 BPF_CALL_0(bpf_get_cgroup_classid_curr)
3059 {
3060 	return __task_get_classid(current);
3061 }
3062 
3063 const struct bpf_func_proto bpf_get_cgroup_classid_curr_proto = {
3064 	.func		= bpf_get_cgroup_classid_curr,
3065 	.gpl_only	= false,
3066 	.ret_type	= RET_INTEGER,
3067 };
3068 
BPF_CALL_1(bpf_skb_cgroup_classid,const struct sk_buff *,skb)3069 BPF_CALL_1(bpf_skb_cgroup_classid, const struct sk_buff *, skb)
3070 {
3071 	struct sock *sk = skb_to_full_sk(skb);
3072 
3073 	if (!sk || !sk_fullsock(sk))
3074 		return 0;
3075 
3076 	return sock_cgroup_classid(&sk->sk_cgrp_data);
3077 }
3078 
3079 static const struct bpf_func_proto bpf_skb_cgroup_classid_proto = {
3080 	.func		= bpf_skb_cgroup_classid,
3081 	.gpl_only	= false,
3082 	.ret_type	= RET_INTEGER,
3083 	.arg1_type	= ARG_PTR_TO_CTX,
3084 };
3085 #endif
3086 
BPF_CALL_1(bpf_get_cgroup_classid,const struct sk_buff *,skb)3087 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
3088 {
3089 	return task_get_classid(skb);
3090 }
3091 
3092 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
3093 	.func           = bpf_get_cgroup_classid,
3094 	.gpl_only       = false,
3095 	.ret_type       = RET_INTEGER,
3096 	.arg1_type      = ARG_PTR_TO_CTX,
3097 };
3098 
BPF_CALL_1(bpf_get_route_realm,const struct sk_buff *,skb)3099 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
3100 {
3101 	return dst_tclassid(skb);
3102 }
3103 
3104 static const struct bpf_func_proto bpf_get_route_realm_proto = {
3105 	.func           = bpf_get_route_realm,
3106 	.gpl_only       = false,
3107 	.ret_type       = RET_INTEGER,
3108 	.arg1_type      = ARG_PTR_TO_CTX,
3109 };
3110 
BPF_CALL_1(bpf_get_hash_recalc,struct sk_buff *,skb)3111 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
3112 {
3113 	/* If skb_clear_hash() was called due to mangling, we can
3114 	 * trigger SW recalculation here. Later access to hash
3115 	 * can then use the inline skb->hash via context directly
3116 	 * instead of calling this helper again.
3117 	 */
3118 	return skb_get_hash(skb);
3119 }
3120 
3121 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
3122 	.func		= bpf_get_hash_recalc,
3123 	.gpl_only	= false,
3124 	.ret_type	= RET_INTEGER,
3125 	.arg1_type	= ARG_PTR_TO_CTX,
3126 };
3127 
BPF_CALL_1(bpf_set_hash_invalid,struct sk_buff *,skb)3128 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
3129 {
3130 	/* After all direct packet write, this can be used once for
3131 	 * triggering a lazy recalc on next skb_get_hash() invocation.
3132 	 */
3133 	skb_clear_hash(skb);
3134 	return 0;
3135 }
3136 
3137 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
3138 	.func		= bpf_set_hash_invalid,
3139 	.gpl_only	= false,
3140 	.ret_type	= RET_INTEGER,
3141 	.arg1_type	= ARG_PTR_TO_CTX,
3142 };
3143 
BPF_CALL_2(bpf_set_hash,struct sk_buff *,skb,u32,hash)3144 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
3145 {
3146 	/* Set user specified hash as L4(+), so that it gets returned
3147 	 * on skb_get_hash() call unless BPF prog later on triggers a
3148 	 * skb_clear_hash().
3149 	 */
3150 	__skb_set_sw_hash(skb, hash, true);
3151 	return 0;
3152 }
3153 
3154 static const struct bpf_func_proto bpf_set_hash_proto = {
3155 	.func		= bpf_set_hash,
3156 	.gpl_only	= false,
3157 	.ret_type	= RET_INTEGER,
3158 	.arg1_type	= ARG_PTR_TO_CTX,
3159 	.arg2_type	= ARG_ANYTHING,
3160 };
3161 
BPF_CALL_3(bpf_skb_vlan_push,struct sk_buff *,skb,__be16,vlan_proto,u16,vlan_tci)3162 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
3163 	   u16, vlan_tci)
3164 {
3165 	int ret;
3166 
3167 	if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
3168 		     vlan_proto != htons(ETH_P_8021AD)))
3169 		vlan_proto = htons(ETH_P_8021Q);
3170 
3171 	bpf_push_mac_rcsum(skb);
3172 	ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
3173 	bpf_pull_mac_rcsum(skb);
3174 
3175 	bpf_compute_data_pointers(skb);
3176 	return ret;
3177 }
3178 
3179 static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
3180 	.func           = bpf_skb_vlan_push,
3181 	.gpl_only       = false,
3182 	.ret_type       = RET_INTEGER,
3183 	.arg1_type      = ARG_PTR_TO_CTX,
3184 	.arg2_type      = ARG_ANYTHING,
3185 	.arg3_type      = ARG_ANYTHING,
3186 };
3187 
BPF_CALL_1(bpf_skb_vlan_pop,struct sk_buff *,skb)3188 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
3189 {
3190 	int ret;
3191 
3192 	bpf_push_mac_rcsum(skb);
3193 	ret = skb_vlan_pop(skb);
3194 	bpf_pull_mac_rcsum(skb);
3195 
3196 	bpf_compute_data_pointers(skb);
3197 	return ret;
3198 }
3199 
3200 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
3201 	.func           = bpf_skb_vlan_pop,
3202 	.gpl_only       = false,
3203 	.ret_type       = RET_INTEGER,
3204 	.arg1_type      = ARG_PTR_TO_CTX,
3205 };
3206 
bpf_skb_generic_push(struct sk_buff * skb,u32 off,u32 len)3207 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
3208 {
3209 	/* Caller already did skb_cow() with len as headroom,
3210 	 * so no need to do it here.
3211 	 */
3212 	skb_push(skb, len);
3213 	memmove(skb->data, skb->data + len, off);
3214 	memset(skb->data + off, 0, len);
3215 
3216 	/* No skb_postpush_rcsum(skb, skb->data + off, len)
3217 	 * needed here as it does not change the skb->csum
3218 	 * result for checksum complete when summing over
3219 	 * zeroed blocks.
3220 	 */
3221 	return 0;
3222 }
3223 
bpf_skb_generic_pop(struct sk_buff * skb,u32 off,u32 len)3224 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
3225 {
3226 	void *old_data;
3227 
3228 	/* skb_ensure_writable() is not needed here, as we're
3229 	 * already working on an uncloned skb.
3230 	 */
3231 	if (unlikely(!pskb_may_pull(skb, off + len)))
3232 		return -ENOMEM;
3233 
3234 	old_data = skb->data;
3235 	__skb_pull(skb, len);
3236 	skb_postpull_rcsum(skb, old_data + off, len);
3237 	memmove(skb->data, old_data, off);
3238 
3239 	return 0;
3240 }
3241 
bpf_skb_net_hdr_push(struct sk_buff * skb,u32 off,u32 len)3242 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
3243 {
3244 	bool trans_same = skb->transport_header == skb->network_header;
3245 	int ret;
3246 
3247 	/* There's no need for __skb_push()/__skb_pull() pair to
3248 	 * get to the start of the mac header as we're guaranteed
3249 	 * to always start from here under eBPF.
3250 	 */
3251 	ret = bpf_skb_generic_push(skb, off, len);
3252 	if (likely(!ret)) {
3253 		skb->mac_header -= len;
3254 		skb->network_header -= len;
3255 		if (trans_same)
3256 			skb->transport_header = skb->network_header;
3257 	}
3258 
3259 	return ret;
3260 }
3261 
bpf_skb_net_hdr_pop(struct sk_buff * skb,u32 off,u32 len)3262 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
3263 {
3264 	bool trans_same = skb->transport_header == skb->network_header;
3265 	int ret;
3266 
3267 	/* Same here, __skb_push()/__skb_pull() pair not needed. */
3268 	ret = bpf_skb_generic_pop(skb, off, len);
3269 	if (likely(!ret)) {
3270 		skb->mac_header += len;
3271 		skb->network_header += len;
3272 		if (trans_same)
3273 			skb->transport_header = skb->network_header;
3274 	}
3275 
3276 	return ret;
3277 }
3278 
bpf_skb_proto_4_to_6(struct sk_buff * skb)3279 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
3280 {
3281 	const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3282 	u32 off = skb_mac_header_len(skb);
3283 	int ret;
3284 
3285 	ret = skb_cow(skb, len_diff);
3286 	if (unlikely(ret < 0))
3287 		return ret;
3288 
3289 	ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3290 	if (unlikely(ret < 0))
3291 		return ret;
3292 
3293 	if (skb_is_gso(skb)) {
3294 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3295 
3296 		/* SKB_GSO_TCPV4 needs to be changed into SKB_GSO_TCPV6. */
3297 		if (shinfo->gso_type & SKB_GSO_TCPV4) {
3298 			shinfo->gso_type &= ~SKB_GSO_TCPV4;
3299 			shinfo->gso_type |=  SKB_GSO_TCPV6;
3300 		}
3301 	}
3302 
3303 	skb->protocol = htons(ETH_P_IPV6);
3304 	skb_clear_hash(skb);
3305 
3306 	return 0;
3307 }
3308 
bpf_skb_proto_6_to_4(struct sk_buff * skb)3309 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
3310 {
3311 	const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3312 	u32 off = skb_mac_header_len(skb);
3313 	int ret;
3314 
3315 	ret = skb_unclone(skb, GFP_ATOMIC);
3316 	if (unlikely(ret < 0))
3317 		return ret;
3318 
3319 	ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3320 	if (unlikely(ret < 0))
3321 		return ret;
3322 
3323 	if (skb_is_gso(skb)) {
3324 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3325 
3326 		/* SKB_GSO_TCPV6 needs to be changed into SKB_GSO_TCPV4. */
3327 		if (shinfo->gso_type & SKB_GSO_TCPV6) {
3328 			shinfo->gso_type &= ~SKB_GSO_TCPV6;
3329 			shinfo->gso_type |=  SKB_GSO_TCPV4;
3330 		}
3331 	}
3332 
3333 	skb->protocol = htons(ETH_P_IP);
3334 	skb_clear_hash(skb);
3335 
3336 	return 0;
3337 }
3338 
bpf_skb_proto_xlat(struct sk_buff * skb,__be16 to_proto)3339 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
3340 {
3341 	__be16 from_proto = skb->protocol;
3342 
3343 	if (from_proto == htons(ETH_P_IP) &&
3344 	      to_proto == htons(ETH_P_IPV6))
3345 		return bpf_skb_proto_4_to_6(skb);
3346 
3347 	if (from_proto == htons(ETH_P_IPV6) &&
3348 	      to_proto == htons(ETH_P_IP))
3349 		return bpf_skb_proto_6_to_4(skb);
3350 
3351 	return -ENOTSUPP;
3352 }
3353 
BPF_CALL_3(bpf_skb_change_proto,struct sk_buff *,skb,__be16,proto,u64,flags)3354 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
3355 	   u64, flags)
3356 {
3357 	int ret;
3358 
3359 	if (unlikely(flags))
3360 		return -EINVAL;
3361 
3362 	/* General idea is that this helper does the basic groundwork
3363 	 * needed for changing the protocol, and eBPF program fills the
3364 	 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
3365 	 * and other helpers, rather than passing a raw buffer here.
3366 	 *
3367 	 * The rationale is to keep this minimal and without a need to
3368 	 * deal with raw packet data. F.e. even if we would pass buffers
3369 	 * here, the program still needs to call the bpf_lX_csum_replace()
3370 	 * helpers anyway. Plus, this way we keep also separation of
3371 	 * concerns, since f.e. bpf_skb_store_bytes() should only take
3372 	 * care of stores.
3373 	 *
3374 	 * Currently, additional options and extension header space are
3375 	 * not supported, but flags register is reserved so we can adapt
3376 	 * that. For offloads, we mark packet as dodgy, so that headers
3377 	 * need to be verified first.
3378 	 */
3379 	ret = bpf_skb_proto_xlat(skb, proto);
3380 	bpf_compute_data_pointers(skb);
3381 	return ret;
3382 }
3383 
3384 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
3385 	.func		= bpf_skb_change_proto,
3386 	.gpl_only	= false,
3387 	.ret_type	= RET_INTEGER,
3388 	.arg1_type	= ARG_PTR_TO_CTX,
3389 	.arg2_type	= ARG_ANYTHING,
3390 	.arg3_type	= ARG_ANYTHING,
3391 };
3392 
BPF_CALL_2(bpf_skb_change_type,struct sk_buff *,skb,u32,pkt_type)3393 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
3394 {
3395 	/* We only allow a restricted subset to be changed for now. */
3396 	if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
3397 		     !skb_pkt_type_ok(pkt_type)))
3398 		return -EINVAL;
3399 
3400 	skb->pkt_type = pkt_type;
3401 	return 0;
3402 }
3403 
3404 static const struct bpf_func_proto bpf_skb_change_type_proto = {
3405 	.func		= bpf_skb_change_type,
3406 	.gpl_only	= false,
3407 	.ret_type	= RET_INTEGER,
3408 	.arg1_type	= ARG_PTR_TO_CTX,
3409 	.arg2_type	= ARG_ANYTHING,
3410 };
3411 
bpf_skb_net_base_len(const struct sk_buff * skb)3412 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
3413 {
3414 	switch (skb->protocol) {
3415 	case htons(ETH_P_IP):
3416 		return sizeof(struct iphdr);
3417 	case htons(ETH_P_IPV6):
3418 		return sizeof(struct ipv6hdr);
3419 	default:
3420 		return ~0U;
3421 	}
3422 }
3423 
3424 #define BPF_F_ADJ_ROOM_ENCAP_L3_MASK	(BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | \
3425 					 BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3426 
3427 #define BPF_F_ADJ_ROOM_DECAP_L3_MASK	(BPF_F_ADJ_ROOM_DECAP_L3_IPV4 | \
3428 					 BPF_F_ADJ_ROOM_DECAP_L3_IPV6)
3429 
3430 #define BPF_F_ADJ_ROOM_MASK		(BPF_F_ADJ_ROOM_FIXED_GSO | \
3431 					 BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \
3432 					 BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \
3433 					 BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \
3434 					 BPF_F_ADJ_ROOM_ENCAP_L2_ETH | \
3435 					 BPF_F_ADJ_ROOM_ENCAP_L2( \
3436 					  BPF_ADJ_ROOM_ENCAP_L2_MASK) | \
3437 					 BPF_F_ADJ_ROOM_DECAP_L3_MASK)
3438 
bpf_skb_net_grow(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3439 static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff,
3440 			    u64 flags)
3441 {
3442 	u8 inner_mac_len = flags >> BPF_ADJ_ROOM_ENCAP_L2_SHIFT;
3443 	bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK;
3444 	u16 mac_len = 0, inner_net = 0, inner_trans = 0;
3445 	unsigned int gso_type = SKB_GSO_DODGY;
3446 	int ret;
3447 
3448 	if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3449 		/* udp gso_size delineates datagrams, only allow if fixed */
3450 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3451 		    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3452 			return -ENOTSUPP;
3453 	}
3454 
3455 	ret = skb_cow_head(skb, len_diff);
3456 	if (unlikely(ret < 0))
3457 		return ret;
3458 
3459 	if (encap) {
3460 		if (skb->protocol != htons(ETH_P_IP) &&
3461 		    skb->protocol != htons(ETH_P_IPV6))
3462 			return -ENOTSUPP;
3463 
3464 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 &&
3465 		    flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3466 			return -EINVAL;
3467 
3468 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE &&
3469 		    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3470 			return -EINVAL;
3471 
3472 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH &&
3473 		    inner_mac_len < ETH_HLEN)
3474 			return -EINVAL;
3475 
3476 		if (skb->encapsulation)
3477 			return -EALREADY;
3478 
3479 		mac_len = skb->network_header - skb->mac_header;
3480 		inner_net = skb->network_header;
3481 		if (inner_mac_len > len_diff)
3482 			return -EINVAL;
3483 		inner_trans = skb->transport_header;
3484 	}
3485 
3486 	ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3487 	if (unlikely(ret < 0))
3488 		return ret;
3489 
3490 	if (encap) {
3491 		skb->inner_mac_header = inner_net - inner_mac_len;
3492 		skb->inner_network_header = inner_net;
3493 		skb->inner_transport_header = inner_trans;
3494 
3495 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH)
3496 			skb_set_inner_protocol(skb, htons(ETH_P_TEB));
3497 		else
3498 			skb_set_inner_protocol(skb, skb->protocol);
3499 
3500 		skb->encapsulation = 1;
3501 		skb_set_network_header(skb, mac_len);
3502 
3503 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3504 			gso_type |= SKB_GSO_UDP_TUNNEL;
3505 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE)
3506 			gso_type |= SKB_GSO_GRE;
3507 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3508 			gso_type |= SKB_GSO_IPXIP6;
3509 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3510 			gso_type |= SKB_GSO_IPXIP4;
3511 
3512 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||
3513 		    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) {
3514 			int nh_len = flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 ?
3515 					sizeof(struct ipv6hdr) :
3516 					sizeof(struct iphdr);
3517 
3518 			skb_set_transport_header(skb, mac_len + nh_len);
3519 		}
3520 
3521 		/* Match skb->protocol to new outer l3 protocol */
3522 		if (skb->protocol == htons(ETH_P_IP) &&
3523 		    flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3524 			skb->protocol = htons(ETH_P_IPV6);
3525 		else if (skb->protocol == htons(ETH_P_IPV6) &&
3526 			 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3527 			skb->protocol = htons(ETH_P_IP);
3528 	}
3529 
3530 	if (skb_is_gso(skb)) {
3531 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3532 
3533 		/* Due to header grow, MSS needs to be downgraded. */
3534 		if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3535 			skb_decrease_gso_size(shinfo, len_diff);
3536 
3537 		/* Header must be checked, and gso_segs recomputed. */
3538 		shinfo->gso_type |= gso_type;
3539 		shinfo->gso_segs = 0;
3540 	}
3541 
3542 	return 0;
3543 }
3544 
bpf_skb_net_shrink(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3545 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff,
3546 			      u64 flags)
3547 {
3548 	int ret;
3549 
3550 	if (unlikely(flags & ~(BPF_F_ADJ_ROOM_FIXED_GSO |
3551 			       BPF_F_ADJ_ROOM_DECAP_L3_MASK |
3552 			       BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3553 		return -EINVAL;
3554 
3555 	if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3556 		/* udp gso_size delineates datagrams, only allow if fixed */
3557 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3558 		    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3559 			return -ENOTSUPP;
3560 	}
3561 
3562 	ret = skb_unclone(skb, GFP_ATOMIC);
3563 	if (unlikely(ret < 0))
3564 		return ret;
3565 
3566 	ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3567 	if (unlikely(ret < 0))
3568 		return ret;
3569 
3570 	/* Match skb->protocol to new outer l3 protocol */
3571 	if (skb->protocol == htons(ETH_P_IP) &&
3572 	    flags & BPF_F_ADJ_ROOM_DECAP_L3_IPV6)
3573 		skb->protocol = htons(ETH_P_IPV6);
3574 	else if (skb->protocol == htons(ETH_P_IPV6) &&
3575 		 flags & BPF_F_ADJ_ROOM_DECAP_L3_IPV4)
3576 		skb->protocol = htons(ETH_P_IP);
3577 
3578 	if (skb_is_gso(skb)) {
3579 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3580 
3581 		/* Due to header shrink, MSS can be upgraded. */
3582 		if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3583 			skb_increase_gso_size(shinfo, len_diff);
3584 
3585 		/* Header must be checked, and gso_segs recomputed. */
3586 		shinfo->gso_type |= SKB_GSO_DODGY;
3587 		shinfo->gso_segs = 0;
3588 	}
3589 
3590 	return 0;
3591 }
3592 
3593 #define BPF_SKB_MAX_LEN SKB_MAX_ALLOC
3594 
BPF_CALL_4(sk_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3595 BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3596 	   u32, mode, u64, flags)
3597 {
3598 	u32 len_diff_abs = abs(len_diff);
3599 	bool shrink = len_diff < 0;
3600 	int ret = 0;
3601 
3602 	if (unlikely(flags || mode))
3603 		return -EINVAL;
3604 	if (unlikely(len_diff_abs > 0xfffU))
3605 		return -EFAULT;
3606 
3607 	if (!shrink) {
3608 		ret = skb_cow(skb, len_diff);
3609 		if (unlikely(ret < 0))
3610 			return ret;
3611 		__skb_push(skb, len_diff_abs);
3612 		memset(skb->data, 0, len_diff_abs);
3613 	} else {
3614 		if (unlikely(!pskb_may_pull(skb, len_diff_abs)))
3615 			return -ENOMEM;
3616 		__skb_pull(skb, len_diff_abs);
3617 	}
3618 	if (tls_sw_has_ctx_rx(skb->sk)) {
3619 		struct strp_msg *rxm = strp_msg(skb);
3620 
3621 		rxm->full_len += len_diff;
3622 	}
3623 	return ret;
3624 }
3625 
3626 static const struct bpf_func_proto sk_skb_adjust_room_proto = {
3627 	.func		= sk_skb_adjust_room,
3628 	.gpl_only	= false,
3629 	.ret_type	= RET_INTEGER,
3630 	.arg1_type	= ARG_PTR_TO_CTX,
3631 	.arg2_type	= ARG_ANYTHING,
3632 	.arg3_type	= ARG_ANYTHING,
3633 	.arg4_type	= ARG_ANYTHING,
3634 };
3635 
BPF_CALL_4(bpf_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3636 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3637 	   u32, mode, u64, flags)
3638 {
3639 	u32 len_cur, len_diff_abs = abs(len_diff);
3640 	u32 len_min = bpf_skb_net_base_len(skb);
3641 	u32 len_max = BPF_SKB_MAX_LEN;
3642 	__be16 proto = skb->protocol;
3643 	bool shrink = len_diff < 0;
3644 	u32 off;
3645 	int ret;
3646 
3647 	if (unlikely(flags & ~(BPF_F_ADJ_ROOM_MASK |
3648 			       BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3649 		return -EINVAL;
3650 	if (unlikely(len_diff_abs > 0xfffU))
3651 		return -EFAULT;
3652 	if (unlikely(proto != htons(ETH_P_IP) &&
3653 		     proto != htons(ETH_P_IPV6)))
3654 		return -ENOTSUPP;
3655 
3656 	off = skb_mac_header_len(skb);
3657 	switch (mode) {
3658 	case BPF_ADJ_ROOM_NET:
3659 		off += bpf_skb_net_base_len(skb);
3660 		break;
3661 	case BPF_ADJ_ROOM_MAC:
3662 		break;
3663 	default:
3664 		return -ENOTSUPP;
3665 	}
3666 
3667 	if (flags & BPF_F_ADJ_ROOM_DECAP_L3_MASK) {
3668 		if (!shrink)
3669 			return -EINVAL;
3670 
3671 		switch (flags & BPF_F_ADJ_ROOM_DECAP_L3_MASK) {
3672 		case BPF_F_ADJ_ROOM_DECAP_L3_IPV4:
3673 			len_min = sizeof(struct iphdr);
3674 			break;
3675 		case BPF_F_ADJ_ROOM_DECAP_L3_IPV6:
3676 			len_min = sizeof(struct ipv6hdr);
3677 			break;
3678 		default:
3679 			return -EINVAL;
3680 		}
3681 	}
3682 
3683 	len_cur = skb->len - skb_network_offset(skb);
3684 	if ((shrink && (len_diff_abs >= len_cur ||
3685 			len_cur - len_diff_abs < len_min)) ||
3686 	    (!shrink && (skb->len + len_diff_abs > len_max &&
3687 			 !skb_is_gso(skb))))
3688 		return -ENOTSUPP;
3689 
3690 	ret = shrink ? bpf_skb_net_shrink(skb, off, len_diff_abs, flags) :
3691 		       bpf_skb_net_grow(skb, off, len_diff_abs, flags);
3692 	if (!ret && !(flags & BPF_F_ADJ_ROOM_NO_CSUM_RESET))
3693 		__skb_reset_checksum_unnecessary(skb);
3694 
3695 	bpf_compute_data_pointers(skb);
3696 	return ret;
3697 }
3698 
3699 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
3700 	.func		= bpf_skb_adjust_room,
3701 	.gpl_only	= false,
3702 	.ret_type	= RET_INTEGER,
3703 	.arg1_type	= ARG_PTR_TO_CTX,
3704 	.arg2_type	= ARG_ANYTHING,
3705 	.arg3_type	= ARG_ANYTHING,
3706 	.arg4_type	= ARG_ANYTHING,
3707 };
3708 
__bpf_skb_min_len(const struct sk_buff * skb)3709 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
3710 {
3711 	u32 min_len = skb_network_offset(skb);
3712 
3713 	if (skb_transport_header_was_set(skb))
3714 		min_len = skb_transport_offset(skb);
3715 	if (skb->ip_summed == CHECKSUM_PARTIAL)
3716 		min_len = skb_checksum_start_offset(skb) +
3717 			  skb->csum_offset + sizeof(__sum16);
3718 	return min_len;
3719 }
3720 
bpf_skb_grow_rcsum(struct sk_buff * skb,unsigned int new_len)3721 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
3722 {
3723 	unsigned int old_len = skb->len;
3724 	int ret;
3725 
3726 	ret = __skb_grow_rcsum(skb, new_len);
3727 	if (!ret)
3728 		memset(skb->data + old_len, 0, new_len - old_len);
3729 	return ret;
3730 }
3731 
bpf_skb_trim_rcsum(struct sk_buff * skb,unsigned int new_len)3732 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
3733 {
3734 	return __skb_trim_rcsum(skb, new_len);
3735 }
3736 
__bpf_skb_change_tail(struct sk_buff * skb,u32 new_len,u64 flags)3737 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
3738 					u64 flags)
3739 {
3740 	u32 max_len = BPF_SKB_MAX_LEN;
3741 	u32 min_len = __bpf_skb_min_len(skb);
3742 	int ret;
3743 
3744 	if (unlikely(flags || new_len > max_len || new_len < min_len))
3745 		return -EINVAL;
3746 	if (skb->encapsulation)
3747 		return -ENOTSUPP;
3748 
3749 	/* The basic idea of this helper is that it's performing the
3750 	 * needed work to either grow or trim an skb, and eBPF program
3751 	 * rewrites the rest via helpers like bpf_skb_store_bytes(),
3752 	 * bpf_lX_csum_replace() and others rather than passing a raw
3753 	 * buffer here. This one is a slow path helper and intended
3754 	 * for replies with control messages.
3755 	 *
3756 	 * Like in bpf_skb_change_proto(), we want to keep this rather
3757 	 * minimal and without protocol specifics so that we are able
3758 	 * to separate concerns as in bpf_skb_store_bytes() should only
3759 	 * be the one responsible for writing buffers.
3760 	 *
3761 	 * It's really expected to be a slow path operation here for
3762 	 * control message replies, so we're implicitly linearizing,
3763 	 * uncloning and drop offloads from the skb by this.
3764 	 */
3765 	ret = __bpf_try_make_writable(skb, skb->len);
3766 	if (!ret) {
3767 		if (new_len > skb->len)
3768 			ret = bpf_skb_grow_rcsum(skb, new_len);
3769 		else if (new_len < skb->len)
3770 			ret = bpf_skb_trim_rcsum(skb, new_len);
3771 		if (!ret && skb_is_gso(skb))
3772 			skb_gso_reset(skb);
3773 	}
3774 	return ret;
3775 }
3776 
BPF_CALL_3(bpf_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3777 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3778 	   u64, flags)
3779 {
3780 	int ret = __bpf_skb_change_tail(skb, new_len, flags);
3781 
3782 	bpf_compute_data_pointers(skb);
3783 	return ret;
3784 }
3785 
3786 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
3787 	.func		= bpf_skb_change_tail,
3788 	.gpl_only	= false,
3789 	.ret_type	= RET_INTEGER,
3790 	.arg1_type	= ARG_PTR_TO_CTX,
3791 	.arg2_type	= ARG_ANYTHING,
3792 	.arg3_type	= ARG_ANYTHING,
3793 };
3794 
BPF_CALL_3(sk_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3795 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3796 	   u64, flags)
3797 {
3798 	return __bpf_skb_change_tail(skb, new_len, flags);
3799 }
3800 
3801 static const struct bpf_func_proto sk_skb_change_tail_proto = {
3802 	.func		= sk_skb_change_tail,
3803 	.gpl_only	= false,
3804 	.ret_type	= RET_INTEGER,
3805 	.arg1_type	= ARG_PTR_TO_CTX,
3806 	.arg2_type	= ARG_ANYTHING,
3807 	.arg3_type	= ARG_ANYTHING,
3808 };
3809 
__bpf_skb_change_head(struct sk_buff * skb,u32 head_room,u64 flags)3810 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
3811 					u64 flags)
3812 {
3813 	u32 max_len = BPF_SKB_MAX_LEN;
3814 	u32 new_len = skb->len + head_room;
3815 	int ret;
3816 
3817 	if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
3818 		     new_len < skb->len))
3819 		return -EINVAL;
3820 
3821 	ret = skb_cow(skb, head_room);
3822 	if (likely(!ret)) {
3823 		/* Idea for this helper is that we currently only
3824 		 * allow to expand on mac header. This means that
3825 		 * skb->protocol network header, etc, stay as is.
3826 		 * Compared to bpf_skb_change_tail(), we're more
3827 		 * flexible due to not needing to linearize or
3828 		 * reset GSO. Intention for this helper is to be
3829 		 * used by an L3 skb that needs to push mac header
3830 		 * for redirection into L2 device.
3831 		 */
3832 		__skb_push(skb, head_room);
3833 		memset(skb->data, 0, head_room);
3834 		skb_reset_mac_header(skb);
3835 		skb_reset_mac_len(skb);
3836 	}
3837 
3838 	return ret;
3839 }
3840 
BPF_CALL_3(bpf_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3841 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
3842 	   u64, flags)
3843 {
3844 	int ret = __bpf_skb_change_head(skb, head_room, flags);
3845 
3846 	bpf_compute_data_pointers(skb);
3847 	return ret;
3848 }
3849 
3850 static const struct bpf_func_proto bpf_skb_change_head_proto = {
3851 	.func		= bpf_skb_change_head,
3852 	.gpl_only	= false,
3853 	.ret_type	= RET_INTEGER,
3854 	.arg1_type	= ARG_PTR_TO_CTX,
3855 	.arg2_type	= ARG_ANYTHING,
3856 	.arg3_type	= ARG_ANYTHING,
3857 };
3858 
BPF_CALL_3(sk_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3859 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
3860 	   u64, flags)
3861 {
3862 	return __bpf_skb_change_head(skb, head_room, flags);
3863 }
3864 
3865 static const struct bpf_func_proto sk_skb_change_head_proto = {
3866 	.func		= sk_skb_change_head,
3867 	.gpl_only	= false,
3868 	.ret_type	= RET_INTEGER,
3869 	.arg1_type	= ARG_PTR_TO_CTX,
3870 	.arg2_type	= ARG_ANYTHING,
3871 	.arg3_type	= ARG_ANYTHING,
3872 };
3873 
BPF_CALL_1(bpf_xdp_get_buff_len,struct xdp_buff *,xdp)3874 BPF_CALL_1(bpf_xdp_get_buff_len, struct xdp_buff*, xdp)
3875 {
3876 	return xdp_get_buff_len(xdp);
3877 }
3878 
3879 static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = {
3880 	.func		= bpf_xdp_get_buff_len,
3881 	.gpl_only	= false,
3882 	.ret_type	= RET_INTEGER,
3883 	.arg1_type	= ARG_PTR_TO_CTX,
3884 };
3885 
3886 BTF_ID_LIST_SINGLE(bpf_xdp_get_buff_len_bpf_ids, struct, xdp_buff)
3887 
3888 const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto = {
3889 	.func		= bpf_xdp_get_buff_len,
3890 	.gpl_only	= false,
3891 	.arg1_type	= ARG_PTR_TO_BTF_ID,
3892 	.arg1_btf_id	= &bpf_xdp_get_buff_len_bpf_ids[0],
3893 };
3894 
xdp_get_metalen(const struct xdp_buff * xdp)3895 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
3896 {
3897 	return xdp_data_meta_unsupported(xdp) ? 0 :
3898 	       xdp->data - xdp->data_meta;
3899 }
3900 
BPF_CALL_2(bpf_xdp_adjust_head,struct xdp_buff *,xdp,int,offset)3901 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
3902 {
3903 	void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3904 	unsigned long metalen = xdp_get_metalen(xdp);
3905 	void *data_start = xdp_frame_end + metalen;
3906 	void *data = xdp->data + offset;
3907 
3908 	if (unlikely(data < data_start ||
3909 		     data > xdp->data_end - ETH_HLEN))
3910 		return -EINVAL;
3911 
3912 	if (metalen)
3913 		memmove(xdp->data_meta + offset,
3914 			xdp->data_meta, metalen);
3915 	xdp->data_meta += offset;
3916 	xdp->data = data;
3917 
3918 	return 0;
3919 }
3920 
3921 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
3922 	.func		= bpf_xdp_adjust_head,
3923 	.gpl_only	= false,
3924 	.ret_type	= RET_INTEGER,
3925 	.arg1_type	= ARG_PTR_TO_CTX,
3926 	.arg2_type	= ARG_ANYTHING,
3927 };
3928 
bpf_xdp_copy_buf(struct xdp_buff * xdp,unsigned long off,void * buf,unsigned long len,bool flush)3929 void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
3930 		      void *buf, unsigned long len, bool flush)
3931 {
3932 	unsigned long ptr_len, ptr_off = 0;
3933 	skb_frag_t *next_frag, *end_frag;
3934 	struct skb_shared_info *sinfo;
3935 	void *src, *dst;
3936 	u8 *ptr_buf;
3937 
3938 	if (likely(xdp->data_end - xdp->data >= off + len)) {
3939 		src = flush ? buf : xdp->data + off;
3940 		dst = flush ? xdp->data + off : buf;
3941 		memcpy(dst, src, len);
3942 		return;
3943 	}
3944 
3945 	sinfo = xdp_get_shared_info_from_buff(xdp);
3946 	end_frag = &sinfo->frags[sinfo->nr_frags];
3947 	next_frag = &sinfo->frags[0];
3948 
3949 	ptr_len = xdp->data_end - xdp->data;
3950 	ptr_buf = xdp->data;
3951 
3952 	while (true) {
3953 		if (off < ptr_off + ptr_len) {
3954 			unsigned long copy_off = off - ptr_off;
3955 			unsigned long copy_len = min(len, ptr_len - copy_off);
3956 
3957 			src = flush ? buf : ptr_buf + copy_off;
3958 			dst = flush ? ptr_buf + copy_off : buf;
3959 			memcpy(dst, src, copy_len);
3960 
3961 			off += copy_len;
3962 			len -= copy_len;
3963 			buf += copy_len;
3964 		}
3965 
3966 		if (!len || next_frag == end_frag)
3967 			break;
3968 
3969 		ptr_off += ptr_len;
3970 		ptr_buf = skb_frag_address(next_frag);
3971 		ptr_len = skb_frag_size(next_frag);
3972 		next_frag++;
3973 	}
3974 }
3975 
bpf_xdp_pointer(struct xdp_buff * xdp,u32 offset,u32 len)3976 void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
3977 {
3978 	u32 size = xdp->data_end - xdp->data;
3979 	struct skb_shared_info *sinfo;
3980 	void *addr = xdp->data;
3981 	int i;
3982 
3983 	if (unlikely(offset > 0xffff || len > 0xffff))
3984 		return ERR_PTR(-EFAULT);
3985 
3986 	if (unlikely(offset + len > xdp_get_buff_len(xdp)))
3987 		return ERR_PTR(-EINVAL);
3988 
3989 	if (likely(offset < size)) /* linear area */
3990 		goto out;
3991 
3992 	sinfo = xdp_get_shared_info_from_buff(xdp);
3993 	offset -= size;
3994 	for (i = 0; i < sinfo->nr_frags; i++) { /* paged area */
3995 		u32 frag_size = skb_frag_size(&sinfo->frags[i]);
3996 
3997 		if  (offset < frag_size) {
3998 			addr = skb_frag_address(&sinfo->frags[i]);
3999 			size = frag_size;
4000 			break;
4001 		}
4002 		offset -= frag_size;
4003 	}
4004 out:
4005 	return offset + len <= size ? addr + offset : NULL;
4006 }
4007 
BPF_CALL_4(bpf_xdp_load_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)4008 BPF_CALL_4(bpf_xdp_load_bytes, struct xdp_buff *, xdp, u32, offset,
4009 	   void *, buf, u32, len)
4010 {
4011 	void *ptr;
4012 
4013 	ptr = bpf_xdp_pointer(xdp, offset, len);
4014 	if (IS_ERR(ptr))
4015 		return PTR_ERR(ptr);
4016 
4017 	if (!ptr)
4018 		bpf_xdp_copy_buf(xdp, offset, buf, len, false);
4019 	else
4020 		memcpy(buf, ptr, len);
4021 
4022 	return 0;
4023 }
4024 
4025 static const struct bpf_func_proto bpf_xdp_load_bytes_proto = {
4026 	.func		= bpf_xdp_load_bytes,
4027 	.gpl_only	= false,
4028 	.ret_type	= RET_INTEGER,
4029 	.arg1_type	= ARG_PTR_TO_CTX,
4030 	.arg2_type	= ARG_ANYTHING,
4031 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
4032 	.arg4_type	= ARG_CONST_SIZE,
4033 };
4034 
__bpf_xdp_load_bytes(struct xdp_buff * xdp,u32 offset,void * buf,u32 len)4035 int __bpf_xdp_load_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len)
4036 {
4037 	return ____bpf_xdp_load_bytes(xdp, offset, buf, len);
4038 }
4039 
BPF_CALL_4(bpf_xdp_store_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)4040 BPF_CALL_4(bpf_xdp_store_bytes, struct xdp_buff *, xdp, u32, offset,
4041 	   void *, buf, u32, len)
4042 {
4043 	void *ptr;
4044 
4045 	ptr = bpf_xdp_pointer(xdp, offset, len);
4046 	if (IS_ERR(ptr))
4047 		return PTR_ERR(ptr);
4048 
4049 	if (!ptr)
4050 		bpf_xdp_copy_buf(xdp, offset, buf, len, true);
4051 	else
4052 		memcpy(ptr, buf, len);
4053 
4054 	return 0;
4055 }
4056 
4057 static const struct bpf_func_proto bpf_xdp_store_bytes_proto = {
4058 	.func		= bpf_xdp_store_bytes,
4059 	.gpl_only	= false,
4060 	.ret_type	= RET_INTEGER,
4061 	.arg1_type	= ARG_PTR_TO_CTX,
4062 	.arg2_type	= ARG_ANYTHING,
4063 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
4064 	.arg4_type	= ARG_CONST_SIZE,
4065 };
4066 
__bpf_xdp_store_bytes(struct xdp_buff * xdp,u32 offset,void * buf,u32 len)4067 int __bpf_xdp_store_bytes(struct xdp_buff *xdp, u32 offset, void *buf, u32 len)
4068 {
4069 	return ____bpf_xdp_store_bytes(xdp, offset, buf, len);
4070 }
4071 
bpf_xdp_frags_increase_tail(struct xdp_buff * xdp,int offset)4072 static int bpf_xdp_frags_increase_tail(struct xdp_buff *xdp, int offset)
4073 {
4074 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
4075 	skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags - 1];
4076 	struct xdp_rxq_info *rxq = xdp->rxq;
4077 	unsigned int tailroom;
4078 
4079 	if (!rxq->frag_size || rxq->frag_size > xdp->frame_sz)
4080 		return -EOPNOTSUPP;
4081 
4082 	tailroom = rxq->frag_size - skb_frag_size(frag) - skb_frag_off(frag);
4083 	if (unlikely(offset > tailroom))
4084 		return -EINVAL;
4085 
4086 	memset(skb_frag_address(frag) + skb_frag_size(frag), 0, offset);
4087 	skb_frag_size_add(frag, offset);
4088 	sinfo->xdp_frags_size += offset;
4089 	if (rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL)
4090 		xsk_buff_get_tail(xdp)->data_end += offset;
4091 
4092 	return 0;
4093 }
4094 
bpf_xdp_shrink_data_zc(struct xdp_buff * xdp,int shrink,struct xdp_mem_info * mem_info,bool release)4095 static void bpf_xdp_shrink_data_zc(struct xdp_buff *xdp, int shrink,
4096 				   struct xdp_mem_info *mem_info, bool release)
4097 {
4098 	struct xdp_buff *zc_frag = xsk_buff_get_tail(xdp);
4099 
4100 	if (release) {
4101 		xsk_buff_del_tail(zc_frag);
4102 		__xdp_return(NULL, mem_info, false, zc_frag);
4103 	} else {
4104 		zc_frag->data_end -= shrink;
4105 	}
4106 }
4107 
bpf_xdp_shrink_data(struct xdp_buff * xdp,skb_frag_t * frag,int shrink)4108 static bool bpf_xdp_shrink_data(struct xdp_buff *xdp, skb_frag_t *frag,
4109 				int shrink)
4110 {
4111 	struct xdp_mem_info *mem_info = &xdp->rxq->mem;
4112 	bool release = skb_frag_size(frag) == shrink;
4113 
4114 	if (mem_info->type == MEM_TYPE_XSK_BUFF_POOL) {
4115 		bpf_xdp_shrink_data_zc(xdp, shrink, mem_info, release);
4116 		goto out;
4117 	}
4118 
4119 	if (release) {
4120 		struct page *page = skb_frag_page(frag);
4121 
4122 		__xdp_return(page_address(page), mem_info, false, NULL);
4123 	}
4124 
4125 out:
4126 	return release;
4127 }
4128 
bpf_xdp_frags_shrink_tail(struct xdp_buff * xdp,int offset)4129 static int bpf_xdp_frags_shrink_tail(struct xdp_buff *xdp, int offset)
4130 {
4131 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
4132 	int i, n_frags_free = 0, len_free = 0;
4133 
4134 	if (unlikely(offset > (int)xdp_get_buff_len(xdp) - ETH_HLEN))
4135 		return -EINVAL;
4136 
4137 	for (i = sinfo->nr_frags - 1; i >= 0 && offset > 0; i--) {
4138 		skb_frag_t *frag = &sinfo->frags[i];
4139 		int shrink = min_t(int, offset, skb_frag_size(frag));
4140 
4141 		len_free += shrink;
4142 		offset -= shrink;
4143 		if (bpf_xdp_shrink_data(xdp, frag, shrink)) {
4144 			n_frags_free++;
4145 		} else {
4146 			skb_frag_size_sub(frag, shrink);
4147 			break;
4148 		}
4149 	}
4150 	sinfo->nr_frags -= n_frags_free;
4151 	sinfo->xdp_frags_size -= len_free;
4152 
4153 	if (unlikely(!sinfo->nr_frags)) {
4154 		xdp_buff_clear_frags_flag(xdp);
4155 		xdp->data_end -= offset;
4156 	}
4157 
4158 	return 0;
4159 }
4160 
BPF_CALL_2(bpf_xdp_adjust_tail,struct xdp_buff *,xdp,int,offset)4161 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
4162 {
4163 	void *data_hard_end = xdp_data_hard_end(xdp); /* use xdp->frame_sz */
4164 	void *data_end = xdp->data_end + offset;
4165 
4166 	if (unlikely(xdp_buff_has_frags(xdp))) { /* non-linear xdp buff */
4167 		if (offset < 0)
4168 			return bpf_xdp_frags_shrink_tail(xdp, -offset);
4169 
4170 		return bpf_xdp_frags_increase_tail(xdp, offset);
4171 	}
4172 
4173 	/* Notice that xdp_data_hard_end have reserved some tailroom */
4174 	if (unlikely(data_end > data_hard_end))
4175 		return -EINVAL;
4176 
4177 	if (unlikely(data_end < xdp->data + ETH_HLEN))
4178 		return -EINVAL;
4179 
4180 	/* Clear memory area on grow, can contain uninit kernel memory */
4181 	if (offset > 0)
4182 		memset(xdp->data_end, 0, offset);
4183 
4184 	xdp->data_end = data_end;
4185 
4186 	return 0;
4187 }
4188 
4189 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
4190 	.func		= bpf_xdp_adjust_tail,
4191 	.gpl_only	= false,
4192 	.ret_type	= RET_INTEGER,
4193 	.arg1_type	= ARG_PTR_TO_CTX,
4194 	.arg2_type	= ARG_ANYTHING,
4195 };
4196 
BPF_CALL_2(bpf_xdp_adjust_meta,struct xdp_buff *,xdp,int,offset)4197 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
4198 {
4199 	void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
4200 	void *meta = xdp->data_meta + offset;
4201 	unsigned long metalen = xdp->data - meta;
4202 
4203 	if (xdp_data_meta_unsupported(xdp))
4204 		return -ENOTSUPP;
4205 	if (unlikely(meta < xdp_frame_end ||
4206 		     meta > xdp->data))
4207 		return -EINVAL;
4208 	if (unlikely(xdp_metalen_invalid(metalen)))
4209 		return -EACCES;
4210 
4211 	xdp->data_meta = meta;
4212 
4213 	return 0;
4214 }
4215 
4216 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
4217 	.func		= bpf_xdp_adjust_meta,
4218 	.gpl_only	= false,
4219 	.ret_type	= RET_INTEGER,
4220 	.arg1_type	= ARG_PTR_TO_CTX,
4221 	.arg2_type	= ARG_ANYTHING,
4222 };
4223 
4224 /**
4225  * DOC: xdp redirect
4226  *
4227  * XDP_REDIRECT works by a three-step process, implemented in the functions
4228  * below:
4229  *
4230  * 1. The bpf_redirect() and bpf_redirect_map() helpers will lookup the target
4231  *    of the redirect and store it (along with some other metadata) in a per-CPU
4232  *    struct bpf_redirect_info.
4233  *
4234  * 2. When the program returns the XDP_REDIRECT return code, the driver will
4235  *    call xdp_do_redirect() which will use the information in struct
4236  *    bpf_redirect_info to actually enqueue the frame into a map type-specific
4237  *    bulk queue structure.
4238  *
4239  * 3. Before exiting its NAPI poll loop, the driver will call
4240  *    xdp_do_flush(), which will flush all the different bulk queues,
4241  *    thus completing the redirect. Note that xdp_do_flush() must be
4242  *    called before napi_complete_done() in the driver, as the
4243  *    XDP_REDIRECT logic relies on being inside a single NAPI instance
4244  *    through to the xdp_do_flush() call for RCU protection of all
4245  *    in-kernel data structures.
4246  */
4247 /*
4248  * Pointers to the map entries will be kept around for this whole sequence of
4249  * steps, protected by RCU. However, there is no top-level rcu_read_lock() in
4250  * the core code; instead, the RCU protection relies on everything happening
4251  * inside a single NAPI poll sequence, which means it's between a pair of calls
4252  * to local_bh_disable()/local_bh_enable().
4253  *
4254  * The map entries are marked as __rcu and the map code makes sure to
4255  * dereference those pointers with rcu_dereference_check() in a way that works
4256  * for both sections that to hold an rcu_read_lock() and sections that are
4257  * called from NAPI without a separate rcu_read_lock(). The code below does not
4258  * use RCU annotations, but relies on those in the map code.
4259  */
xdp_do_flush(void)4260 void xdp_do_flush(void)
4261 {
4262 	__dev_flush();
4263 	__cpu_map_flush();
4264 	__xsk_map_flush();
4265 }
4266 EXPORT_SYMBOL_GPL(xdp_do_flush);
4267 
bpf_clear_redirect_map(struct bpf_map * map)4268 void bpf_clear_redirect_map(struct bpf_map *map)
4269 {
4270 	struct bpf_redirect_info *ri;
4271 	int cpu;
4272 
4273 	for_each_possible_cpu(cpu) {
4274 		ri = per_cpu_ptr(&bpf_redirect_info, cpu);
4275 		/* Avoid polluting remote cacheline due to writes if
4276 		 * not needed. Once we pass this test, we need the
4277 		 * cmpxchg() to make sure it hasn't been changed in
4278 		 * the meantime by remote CPU.
4279 		 */
4280 		if (unlikely(READ_ONCE(ri->map) == map))
4281 			cmpxchg(&ri->map, map, NULL);
4282 	}
4283 }
4284 
4285 DEFINE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
4286 EXPORT_SYMBOL_GPL(bpf_master_redirect_enabled_key);
4287 
xdp_master_redirect(struct xdp_buff * xdp)4288 u32 xdp_master_redirect(struct xdp_buff *xdp)
4289 {
4290 	struct net_device *master, *slave;
4291 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4292 
4293 	master = netdev_master_upper_dev_get_rcu(xdp->rxq->dev);
4294 	slave = master->netdev_ops->ndo_xdp_get_xmit_slave(master, xdp);
4295 	if (slave && slave != xdp->rxq->dev) {
4296 		/* The target device is different from the receiving device, so
4297 		 * redirect it to the new device.
4298 		 * Using XDP_REDIRECT gets the correct behaviour from XDP enabled
4299 		 * drivers to unmap the packet from their rx ring.
4300 		 */
4301 		ri->tgt_index = slave->ifindex;
4302 		ri->map_id = INT_MAX;
4303 		ri->map_type = BPF_MAP_TYPE_UNSPEC;
4304 		return XDP_REDIRECT;
4305 	}
4306 	return XDP_TX;
4307 }
4308 EXPORT_SYMBOL_GPL(xdp_master_redirect);
4309 
__xdp_do_redirect_xsk(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4310 static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri,
4311 					struct net_device *dev,
4312 					struct xdp_buff *xdp,
4313 					struct bpf_prog *xdp_prog)
4314 {
4315 	enum bpf_map_type map_type = ri->map_type;
4316 	void *fwd = ri->tgt_value;
4317 	u32 map_id = ri->map_id;
4318 	int err;
4319 
4320 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4321 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4322 
4323 	err = __xsk_map_redirect(fwd, xdp);
4324 	if (unlikely(err))
4325 		goto err;
4326 
4327 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4328 	return 0;
4329 err:
4330 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4331 	return err;
4332 }
4333 
__xdp_do_redirect_frame(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4334 static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
4335 						   struct net_device *dev,
4336 						   struct xdp_frame *xdpf,
4337 						   struct bpf_prog *xdp_prog)
4338 {
4339 	enum bpf_map_type map_type = ri->map_type;
4340 	void *fwd = ri->tgt_value;
4341 	u32 map_id = ri->map_id;
4342 	u32 flags = ri->flags;
4343 	struct bpf_map *map;
4344 	int err;
4345 
4346 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4347 	ri->flags = 0;
4348 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4349 
4350 	if (unlikely(!xdpf)) {
4351 		err = -EOVERFLOW;
4352 		goto err;
4353 	}
4354 
4355 	switch (map_type) {
4356 	case BPF_MAP_TYPE_DEVMAP:
4357 		fallthrough;
4358 	case BPF_MAP_TYPE_DEVMAP_HASH:
4359 		if (unlikely(flags & BPF_F_BROADCAST)) {
4360 			map = READ_ONCE(ri->map);
4361 
4362 			/* The map pointer is cleared when the map is being torn
4363 			 * down by bpf_clear_redirect_map()
4364 			 */
4365 			if (unlikely(!map)) {
4366 				err = -ENOENT;
4367 				break;
4368 			}
4369 
4370 			WRITE_ONCE(ri->map, NULL);
4371 			err = dev_map_enqueue_multi(xdpf, dev, map,
4372 						    flags & BPF_F_EXCLUDE_INGRESS);
4373 		} else {
4374 			err = dev_map_enqueue(fwd, xdpf, dev);
4375 		}
4376 		break;
4377 	case BPF_MAP_TYPE_CPUMAP:
4378 		err = cpu_map_enqueue(fwd, xdpf, dev);
4379 		break;
4380 	case BPF_MAP_TYPE_UNSPEC:
4381 		if (map_id == INT_MAX) {
4382 			fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4383 			if (unlikely(!fwd)) {
4384 				err = -EINVAL;
4385 				break;
4386 			}
4387 			err = dev_xdp_enqueue(fwd, xdpf, dev);
4388 			break;
4389 		}
4390 		fallthrough;
4391 	default:
4392 		err = -EBADRQC;
4393 	}
4394 
4395 	if (unlikely(err))
4396 		goto err;
4397 
4398 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4399 	return 0;
4400 err:
4401 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4402 	return err;
4403 }
4404 
xdp_do_redirect(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4405 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
4406 		    struct bpf_prog *xdp_prog)
4407 {
4408 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4409 	enum bpf_map_type map_type = ri->map_type;
4410 
4411 	if (map_type == BPF_MAP_TYPE_XSKMAP)
4412 		return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);
4413 
4414 	return __xdp_do_redirect_frame(ri, dev, xdp_convert_buff_to_frame(xdp),
4415 				       xdp_prog);
4416 }
4417 EXPORT_SYMBOL_GPL(xdp_do_redirect);
4418 
xdp_do_redirect_frame(struct net_device * dev,struct xdp_buff * xdp,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4419 int xdp_do_redirect_frame(struct net_device *dev, struct xdp_buff *xdp,
4420 			  struct xdp_frame *xdpf, struct bpf_prog *xdp_prog)
4421 {
4422 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4423 	enum bpf_map_type map_type = ri->map_type;
4424 
4425 	if (map_type == BPF_MAP_TYPE_XSKMAP)
4426 		return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);
4427 
4428 	return __xdp_do_redirect_frame(ri, dev, xdpf, xdp_prog);
4429 }
4430 EXPORT_SYMBOL_GPL(xdp_do_redirect_frame);
4431 
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)4432 static int xdp_do_generic_redirect_map(struct net_device *dev,
4433 				       struct sk_buff *skb,
4434 				       struct xdp_buff *xdp,
4435 				       struct bpf_prog *xdp_prog, void *fwd,
4436 				       enum bpf_map_type map_type, u32 map_id,
4437 				       u32 flags)
4438 {
4439 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4440 	struct bpf_map *map;
4441 	int err;
4442 
4443 	switch (map_type) {
4444 	case BPF_MAP_TYPE_DEVMAP:
4445 		fallthrough;
4446 	case BPF_MAP_TYPE_DEVMAP_HASH:
4447 		if (unlikely(flags & BPF_F_BROADCAST)) {
4448 			map = READ_ONCE(ri->map);
4449 
4450 			/* The map pointer is cleared when the map is being torn
4451 			 * down by bpf_clear_redirect_map()
4452 			 */
4453 			if (unlikely(!map)) {
4454 				err = -ENOENT;
4455 				break;
4456 			}
4457 
4458 			WRITE_ONCE(ri->map, NULL);
4459 			err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
4460 						     flags & BPF_F_EXCLUDE_INGRESS);
4461 		} else {
4462 			err = dev_map_generic_redirect(fwd, skb, xdp_prog);
4463 		}
4464 		if (unlikely(err))
4465 			goto err;
4466 		break;
4467 	case BPF_MAP_TYPE_XSKMAP:
4468 		err = xsk_generic_rcv(fwd, xdp);
4469 		if (err)
4470 			goto err;
4471 		consume_skb(skb);
4472 		break;
4473 	case BPF_MAP_TYPE_CPUMAP:
4474 		err = cpu_map_generic_redirect(fwd, skb);
4475 		if (unlikely(err))
4476 			goto err;
4477 		break;
4478 	default:
4479 		err = -EBADRQC;
4480 		goto err;
4481 	}
4482 
4483 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4484 	return 0;
4485 err:
4486 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4487 	return err;
4488 }
4489 
xdp_do_generic_redirect(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4490 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
4491 			    struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
4492 {
4493 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4494 	enum bpf_map_type map_type = ri->map_type;
4495 	void *fwd = ri->tgt_value;
4496 	u32 map_id = ri->map_id;
4497 	u32 flags = ri->flags;
4498 	int err;
4499 
4500 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4501 	ri->flags = 0;
4502 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4503 
4504 	if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
4505 		fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4506 		if (unlikely(!fwd)) {
4507 			err = -EINVAL;
4508 			goto err;
4509 		}
4510 
4511 		err = xdp_ok_fwd_dev(fwd, skb->len);
4512 		if (unlikely(err))
4513 			goto err;
4514 
4515 		skb->dev = fwd;
4516 		_trace_xdp_redirect(dev, xdp_prog, ri->tgt_index);
4517 		generic_xdp_tx(skb, xdp_prog);
4518 		return 0;
4519 	}
4520 
4521 	return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id, flags);
4522 err:
4523 	_trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
4524 	return err;
4525 }
4526 
BPF_CALL_2(bpf_xdp_redirect,u32,ifindex,u64,flags)4527 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
4528 {
4529 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4530 
4531 	if (unlikely(flags))
4532 		return XDP_ABORTED;
4533 
4534 	/* NB! Map type UNSPEC and map_id == INT_MAX (never generated
4535 	 * by map_idr) is used for ifindex based XDP redirect.
4536 	 */
4537 	ri->tgt_index = ifindex;
4538 	ri->map_id = INT_MAX;
4539 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4540 
4541 	return XDP_REDIRECT;
4542 }
4543 
4544 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
4545 	.func           = bpf_xdp_redirect,
4546 	.gpl_only       = false,
4547 	.ret_type       = RET_INTEGER,
4548 	.arg1_type      = ARG_ANYTHING,
4549 	.arg2_type      = ARG_ANYTHING,
4550 };
4551 
BPF_CALL_3(bpf_xdp_redirect_map,struct bpf_map *,map,u64,key,u64,flags)4552 BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u64, key,
4553 	   u64, flags)
4554 {
4555 	return map->ops->map_redirect(map, key, flags);
4556 }
4557 
4558 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
4559 	.func           = bpf_xdp_redirect_map,
4560 	.gpl_only       = false,
4561 	.ret_type       = RET_INTEGER,
4562 	.arg1_type      = ARG_CONST_MAP_PTR,
4563 	.arg2_type      = ARG_ANYTHING,
4564 	.arg3_type      = ARG_ANYTHING,
4565 };
4566 
bpf_skb_copy(void * dst_buff,const void * skb,unsigned long off,unsigned long len)4567 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
4568 				  unsigned long off, unsigned long len)
4569 {
4570 	void *ptr = skb_header_pointer(skb, off, len, dst_buff);
4571 
4572 	if (unlikely(!ptr))
4573 		return len;
4574 	if (ptr != dst_buff)
4575 		memcpy(dst_buff, ptr, len);
4576 
4577 	return 0;
4578 }
4579 
BPF_CALL_5(bpf_skb_event_output,struct sk_buff *,skb,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4580 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
4581 	   u64, flags, void *, meta, u64, meta_size)
4582 {
4583 	u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4584 
4585 	if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4586 		return -EINVAL;
4587 	if (unlikely(!skb || skb_size > skb->len))
4588 		return -EFAULT;
4589 
4590 	return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
4591 				bpf_skb_copy);
4592 }
4593 
4594 static const struct bpf_func_proto bpf_skb_event_output_proto = {
4595 	.func		= bpf_skb_event_output,
4596 	.gpl_only	= true,
4597 	.ret_type	= RET_INTEGER,
4598 	.arg1_type	= ARG_PTR_TO_CTX,
4599 	.arg2_type	= ARG_CONST_MAP_PTR,
4600 	.arg3_type	= ARG_ANYTHING,
4601 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4602 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4603 };
4604 
4605 BTF_ID_LIST_SINGLE(bpf_skb_output_btf_ids, struct, sk_buff)
4606 
4607 const struct bpf_func_proto bpf_skb_output_proto = {
4608 	.func		= bpf_skb_event_output,
4609 	.gpl_only	= true,
4610 	.ret_type	= RET_INTEGER,
4611 	.arg1_type	= ARG_PTR_TO_BTF_ID,
4612 	.arg1_btf_id	= &bpf_skb_output_btf_ids[0],
4613 	.arg2_type	= ARG_CONST_MAP_PTR,
4614 	.arg3_type	= ARG_ANYTHING,
4615 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4616 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4617 };
4618 
bpf_tunnel_key_af(u64 flags)4619 static unsigned short bpf_tunnel_key_af(u64 flags)
4620 {
4621 	return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
4622 }
4623 
BPF_CALL_4(bpf_skb_get_tunnel_key,struct sk_buff *,skb,struct bpf_tunnel_key *,to,u32,size,u64,flags)4624 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
4625 	   u32, size, u64, flags)
4626 {
4627 	const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4628 	u8 compat[sizeof(struct bpf_tunnel_key)];
4629 	void *to_orig = to;
4630 	int err;
4631 
4632 	if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6 |
4633 					 BPF_F_TUNINFO_FLAGS)))) {
4634 		err = -EINVAL;
4635 		goto err_clear;
4636 	}
4637 	if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
4638 		err = -EPROTO;
4639 		goto err_clear;
4640 	}
4641 	if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4642 		err = -EINVAL;
4643 		switch (size) {
4644 		case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4645 		case offsetof(struct bpf_tunnel_key, tunnel_label):
4646 		case offsetof(struct bpf_tunnel_key, tunnel_ext):
4647 			goto set_compat;
4648 		case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4649 			/* Fixup deprecated structure layouts here, so we have
4650 			 * a common path later on.
4651 			 */
4652 			if (ip_tunnel_info_af(info) != AF_INET)
4653 				goto err_clear;
4654 set_compat:
4655 			to = (struct bpf_tunnel_key *)compat;
4656 			break;
4657 		default:
4658 			goto err_clear;
4659 		}
4660 	}
4661 
4662 	to->tunnel_id = be64_to_cpu(info->key.tun_id);
4663 	to->tunnel_tos = info->key.tos;
4664 	to->tunnel_ttl = info->key.ttl;
4665 	if (flags & BPF_F_TUNINFO_FLAGS)
4666 		to->tunnel_flags = info->key.tun_flags;
4667 	else
4668 		to->tunnel_ext = 0;
4669 
4670 	if (flags & BPF_F_TUNINFO_IPV6) {
4671 		memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
4672 		       sizeof(to->remote_ipv6));
4673 		memcpy(to->local_ipv6, &info->key.u.ipv6.dst,
4674 		       sizeof(to->local_ipv6));
4675 		to->tunnel_label = be32_to_cpu(info->key.label);
4676 	} else {
4677 		to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
4678 		memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
4679 		to->local_ipv4 = be32_to_cpu(info->key.u.ipv4.dst);
4680 		memset(&to->local_ipv6[1], 0, sizeof(__u32) * 3);
4681 		to->tunnel_label = 0;
4682 	}
4683 
4684 	if (unlikely(size != sizeof(struct bpf_tunnel_key)))
4685 		memcpy(to_orig, to, size);
4686 
4687 	return 0;
4688 err_clear:
4689 	memset(to_orig, 0, size);
4690 	return err;
4691 }
4692 
4693 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
4694 	.func		= bpf_skb_get_tunnel_key,
4695 	.gpl_only	= false,
4696 	.ret_type	= RET_INTEGER,
4697 	.arg1_type	= ARG_PTR_TO_CTX,
4698 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
4699 	.arg3_type	= ARG_CONST_SIZE,
4700 	.arg4_type	= ARG_ANYTHING,
4701 };
4702 
BPF_CALL_3(bpf_skb_get_tunnel_opt,struct sk_buff *,skb,u8 *,to,u32,size)4703 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
4704 {
4705 	const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4706 	int err;
4707 
4708 	if (unlikely(!info ||
4709 		     !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
4710 		err = -ENOENT;
4711 		goto err_clear;
4712 	}
4713 	if (unlikely(size < info->options_len)) {
4714 		err = -ENOMEM;
4715 		goto err_clear;
4716 	}
4717 
4718 	ip_tunnel_info_opts_get(to, info);
4719 	if (size > info->options_len)
4720 		memset(to + info->options_len, 0, size - info->options_len);
4721 
4722 	return info->options_len;
4723 err_clear:
4724 	memset(to, 0, size);
4725 	return err;
4726 }
4727 
4728 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
4729 	.func		= bpf_skb_get_tunnel_opt,
4730 	.gpl_only	= false,
4731 	.ret_type	= RET_INTEGER,
4732 	.arg1_type	= ARG_PTR_TO_CTX,
4733 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
4734 	.arg3_type	= ARG_CONST_SIZE,
4735 };
4736 
4737 static struct metadata_dst __percpu *md_dst;
4738 
BPF_CALL_4(bpf_skb_set_tunnel_key,struct sk_buff *,skb,const struct bpf_tunnel_key *,from,u32,size,u64,flags)4739 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
4740 	   const struct bpf_tunnel_key *, from, u32, size, u64, flags)
4741 {
4742 	struct metadata_dst *md = this_cpu_ptr(md_dst);
4743 	u8 compat[sizeof(struct bpf_tunnel_key)];
4744 	struct ip_tunnel_info *info;
4745 
4746 	if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
4747 			       BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER |
4748 			       BPF_F_NO_TUNNEL_KEY)))
4749 		return -EINVAL;
4750 	if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4751 		switch (size) {
4752 		case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4753 		case offsetof(struct bpf_tunnel_key, tunnel_label):
4754 		case offsetof(struct bpf_tunnel_key, tunnel_ext):
4755 		case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4756 			/* Fixup deprecated structure layouts here, so we have
4757 			 * a common path later on.
4758 			 */
4759 			memcpy(compat, from, size);
4760 			memset(compat + size, 0, sizeof(compat) - size);
4761 			from = (const struct bpf_tunnel_key *) compat;
4762 			break;
4763 		default:
4764 			return -EINVAL;
4765 		}
4766 	}
4767 	if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
4768 		     from->tunnel_ext))
4769 		return -EINVAL;
4770 
4771 	skb_dst_drop(skb);
4772 	dst_hold((struct dst_entry *) md);
4773 	skb_dst_set(skb, (struct dst_entry *) md);
4774 
4775 	info = &md->u.tun_info;
4776 	memset(info, 0, sizeof(*info));
4777 	info->mode = IP_TUNNEL_INFO_TX;
4778 
4779 	info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
4780 	if (flags & BPF_F_DONT_FRAGMENT)
4781 		info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
4782 	if (flags & BPF_F_ZERO_CSUM_TX)
4783 		info->key.tun_flags &= ~TUNNEL_CSUM;
4784 	if (flags & BPF_F_SEQ_NUMBER)
4785 		info->key.tun_flags |= TUNNEL_SEQ;
4786 	if (flags & BPF_F_NO_TUNNEL_KEY)
4787 		info->key.tun_flags &= ~TUNNEL_KEY;
4788 
4789 	info->key.tun_id = cpu_to_be64(from->tunnel_id);
4790 	info->key.tos = from->tunnel_tos;
4791 	info->key.ttl = from->tunnel_ttl;
4792 
4793 	if (flags & BPF_F_TUNINFO_IPV6) {
4794 		info->mode |= IP_TUNNEL_INFO_IPV6;
4795 		memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
4796 		       sizeof(from->remote_ipv6));
4797 		memcpy(&info->key.u.ipv6.src, from->local_ipv6,
4798 		       sizeof(from->local_ipv6));
4799 		info->key.label = cpu_to_be32(from->tunnel_label) &
4800 				  IPV6_FLOWLABEL_MASK;
4801 	} else {
4802 		info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
4803 		info->key.u.ipv4.src = cpu_to_be32(from->local_ipv4);
4804 		info->key.flow_flags = FLOWI_FLAG_ANYSRC;
4805 	}
4806 
4807 	return 0;
4808 }
4809 
4810 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
4811 	.func		= bpf_skb_set_tunnel_key,
4812 	.gpl_only	= false,
4813 	.ret_type	= RET_INTEGER,
4814 	.arg1_type	= ARG_PTR_TO_CTX,
4815 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4816 	.arg3_type	= ARG_CONST_SIZE,
4817 	.arg4_type	= ARG_ANYTHING,
4818 };
4819 
BPF_CALL_3(bpf_skb_set_tunnel_opt,struct sk_buff *,skb,const u8 *,from,u32,size)4820 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
4821 	   const u8 *, from, u32, size)
4822 {
4823 	struct ip_tunnel_info *info = skb_tunnel_info(skb);
4824 	const struct metadata_dst *md = this_cpu_ptr(md_dst);
4825 
4826 	if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
4827 		return -EINVAL;
4828 	if (unlikely(size > IP_TUNNEL_OPTS_MAX))
4829 		return -ENOMEM;
4830 
4831 	ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT);
4832 
4833 	return 0;
4834 }
4835 
4836 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
4837 	.func		= bpf_skb_set_tunnel_opt,
4838 	.gpl_only	= false,
4839 	.ret_type	= RET_INTEGER,
4840 	.arg1_type	= ARG_PTR_TO_CTX,
4841 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4842 	.arg3_type	= ARG_CONST_SIZE,
4843 };
4844 
4845 static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)4846 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
4847 {
4848 	if (!md_dst) {
4849 		struct metadata_dst __percpu *tmp;
4850 
4851 		tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
4852 						METADATA_IP_TUNNEL,
4853 						GFP_KERNEL);
4854 		if (!tmp)
4855 			return NULL;
4856 		if (cmpxchg(&md_dst, NULL, tmp))
4857 			metadata_dst_free_percpu(tmp);
4858 	}
4859 
4860 	switch (which) {
4861 	case BPF_FUNC_skb_set_tunnel_key:
4862 		return &bpf_skb_set_tunnel_key_proto;
4863 	case BPF_FUNC_skb_set_tunnel_opt:
4864 		return &bpf_skb_set_tunnel_opt_proto;
4865 	default:
4866 		return NULL;
4867 	}
4868 }
4869 
BPF_CALL_3(bpf_skb_under_cgroup,struct sk_buff *,skb,struct bpf_map *,map,u32,idx)4870 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
4871 	   u32, idx)
4872 {
4873 	struct bpf_array *array = container_of(map, struct bpf_array, map);
4874 	struct cgroup *cgrp;
4875 	struct sock *sk;
4876 
4877 	sk = skb_to_full_sk(skb);
4878 	if (!sk || !sk_fullsock(sk))
4879 		return -ENOENT;
4880 	if (unlikely(idx >= array->map.max_entries))
4881 		return -E2BIG;
4882 
4883 	cgrp = READ_ONCE(array->ptrs[idx]);
4884 	if (unlikely(!cgrp))
4885 		return -EAGAIN;
4886 
4887 	return sk_under_cgroup_hierarchy(sk, cgrp);
4888 }
4889 
4890 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
4891 	.func		= bpf_skb_under_cgroup,
4892 	.gpl_only	= false,
4893 	.ret_type	= RET_INTEGER,
4894 	.arg1_type	= ARG_PTR_TO_CTX,
4895 	.arg2_type	= ARG_CONST_MAP_PTR,
4896 	.arg3_type	= ARG_ANYTHING,
4897 };
4898 
4899 #ifdef CONFIG_SOCK_CGROUP_DATA
__bpf_sk_cgroup_id(struct sock * sk)4900 static inline u64 __bpf_sk_cgroup_id(struct sock *sk)
4901 {
4902 	struct cgroup *cgrp;
4903 
4904 	sk = sk_to_full_sk(sk);
4905 	if (!sk || !sk_fullsock(sk))
4906 		return 0;
4907 
4908 	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4909 	return cgroup_id(cgrp);
4910 }
4911 
BPF_CALL_1(bpf_skb_cgroup_id,const struct sk_buff *,skb)4912 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
4913 {
4914 	return __bpf_sk_cgroup_id(skb->sk);
4915 }
4916 
4917 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
4918 	.func           = bpf_skb_cgroup_id,
4919 	.gpl_only       = false,
4920 	.ret_type       = RET_INTEGER,
4921 	.arg1_type      = ARG_PTR_TO_CTX,
4922 };
4923 
__bpf_sk_ancestor_cgroup_id(struct sock * sk,int ancestor_level)4924 static inline u64 __bpf_sk_ancestor_cgroup_id(struct sock *sk,
4925 					      int ancestor_level)
4926 {
4927 	struct cgroup *ancestor;
4928 	struct cgroup *cgrp;
4929 
4930 	sk = sk_to_full_sk(sk);
4931 	if (!sk || !sk_fullsock(sk))
4932 		return 0;
4933 
4934 	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4935 	ancestor = cgroup_ancestor(cgrp, ancestor_level);
4936 	if (!ancestor)
4937 		return 0;
4938 
4939 	return cgroup_id(ancestor);
4940 }
4941 
BPF_CALL_2(bpf_skb_ancestor_cgroup_id,const struct sk_buff *,skb,int,ancestor_level)4942 BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int,
4943 	   ancestor_level)
4944 {
4945 	return __bpf_sk_ancestor_cgroup_id(skb->sk, ancestor_level);
4946 }
4947 
4948 static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = {
4949 	.func           = bpf_skb_ancestor_cgroup_id,
4950 	.gpl_only       = false,
4951 	.ret_type       = RET_INTEGER,
4952 	.arg1_type      = ARG_PTR_TO_CTX,
4953 	.arg2_type      = ARG_ANYTHING,
4954 };
4955 
BPF_CALL_1(bpf_sk_cgroup_id,struct sock *,sk)4956 BPF_CALL_1(bpf_sk_cgroup_id, struct sock *, sk)
4957 {
4958 	return __bpf_sk_cgroup_id(sk);
4959 }
4960 
4961 static const struct bpf_func_proto bpf_sk_cgroup_id_proto = {
4962 	.func           = bpf_sk_cgroup_id,
4963 	.gpl_only       = false,
4964 	.ret_type       = RET_INTEGER,
4965 	.arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4966 };
4967 
BPF_CALL_2(bpf_sk_ancestor_cgroup_id,struct sock *,sk,int,ancestor_level)4968 BPF_CALL_2(bpf_sk_ancestor_cgroup_id, struct sock *, sk, int, ancestor_level)
4969 {
4970 	return __bpf_sk_ancestor_cgroup_id(sk, ancestor_level);
4971 }
4972 
4973 static const struct bpf_func_proto bpf_sk_ancestor_cgroup_id_proto = {
4974 	.func           = bpf_sk_ancestor_cgroup_id,
4975 	.gpl_only       = false,
4976 	.ret_type       = RET_INTEGER,
4977 	.arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4978 	.arg2_type      = ARG_ANYTHING,
4979 };
4980 #endif
4981 
bpf_xdp_copy(void * dst,const void * ctx,unsigned long off,unsigned long len)4982 static unsigned long bpf_xdp_copy(void *dst, const void *ctx,
4983 				  unsigned long off, unsigned long len)
4984 {
4985 	struct xdp_buff *xdp = (struct xdp_buff *)ctx;
4986 
4987 	bpf_xdp_copy_buf(xdp, off, dst, len, false);
4988 	return 0;
4989 }
4990 
BPF_CALL_5(bpf_xdp_event_output,struct xdp_buff *,xdp,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4991 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
4992 	   u64, flags, void *, meta, u64, meta_size)
4993 {
4994 	u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4995 
4996 	if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4997 		return -EINVAL;
4998 
4999 	if (unlikely(!xdp || xdp_size > xdp_get_buff_len(xdp)))
5000 		return -EFAULT;
5001 
5002 	return bpf_event_output(map, flags, meta, meta_size, xdp,
5003 				xdp_size, bpf_xdp_copy);
5004 }
5005 
5006 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
5007 	.func		= bpf_xdp_event_output,
5008 	.gpl_only	= true,
5009 	.ret_type	= RET_INTEGER,
5010 	.arg1_type	= ARG_PTR_TO_CTX,
5011 	.arg2_type	= ARG_CONST_MAP_PTR,
5012 	.arg3_type	= ARG_ANYTHING,
5013 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5014 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
5015 };
5016 
5017 BTF_ID_LIST_SINGLE(bpf_xdp_output_btf_ids, struct, xdp_buff)
5018 
5019 const struct bpf_func_proto bpf_xdp_output_proto = {
5020 	.func		= bpf_xdp_event_output,
5021 	.gpl_only	= true,
5022 	.ret_type	= RET_INTEGER,
5023 	.arg1_type	= ARG_PTR_TO_BTF_ID,
5024 	.arg1_btf_id	= &bpf_xdp_output_btf_ids[0],
5025 	.arg2_type	= ARG_CONST_MAP_PTR,
5026 	.arg3_type	= ARG_ANYTHING,
5027 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5028 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
5029 };
5030 
BPF_CALL_1(bpf_get_socket_cookie,struct sk_buff *,skb)5031 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
5032 {
5033 	return skb->sk ? __sock_gen_cookie(skb->sk) : 0;
5034 }
5035 
5036 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
5037 	.func           = bpf_get_socket_cookie,
5038 	.gpl_only       = false,
5039 	.ret_type       = RET_INTEGER,
5040 	.arg1_type      = ARG_PTR_TO_CTX,
5041 };
5042 
BPF_CALL_1(bpf_get_socket_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)5043 BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
5044 {
5045 	return __sock_gen_cookie(ctx->sk);
5046 }
5047 
5048 static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
5049 	.func		= bpf_get_socket_cookie_sock_addr,
5050 	.gpl_only	= false,
5051 	.ret_type	= RET_INTEGER,
5052 	.arg1_type	= ARG_PTR_TO_CTX,
5053 };
5054 
BPF_CALL_1(bpf_get_socket_cookie_sock,struct sock *,ctx)5055 BPF_CALL_1(bpf_get_socket_cookie_sock, struct sock *, ctx)
5056 {
5057 	return __sock_gen_cookie(ctx);
5058 }
5059 
5060 static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
5061 	.func		= bpf_get_socket_cookie_sock,
5062 	.gpl_only	= false,
5063 	.ret_type	= RET_INTEGER,
5064 	.arg1_type	= ARG_PTR_TO_CTX,
5065 };
5066 
BPF_CALL_1(bpf_get_socket_ptr_cookie,struct sock *,sk)5067 BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
5068 {
5069 	return sk ? sock_gen_cookie(sk) : 0;
5070 }
5071 
5072 const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
5073 	.func		= bpf_get_socket_ptr_cookie,
5074 	.gpl_only	= false,
5075 	.ret_type	= RET_INTEGER,
5076 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON | PTR_MAYBE_NULL,
5077 };
5078 
BPF_CALL_1(bpf_get_socket_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)5079 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
5080 {
5081 	return __sock_gen_cookie(ctx->sk);
5082 }
5083 
5084 static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
5085 	.func		= bpf_get_socket_cookie_sock_ops,
5086 	.gpl_only	= false,
5087 	.ret_type	= RET_INTEGER,
5088 	.arg1_type	= ARG_PTR_TO_CTX,
5089 };
5090 
__bpf_get_netns_cookie(struct sock * sk)5091 static u64 __bpf_get_netns_cookie(struct sock *sk)
5092 {
5093 	const struct net *net = sk ? sock_net(sk) : &init_net;
5094 
5095 	return net->net_cookie;
5096 }
5097 
BPF_CALL_1(bpf_get_netns_cookie_sock,struct sock *,ctx)5098 BPF_CALL_1(bpf_get_netns_cookie_sock, struct sock *, ctx)
5099 {
5100 	return __bpf_get_netns_cookie(ctx);
5101 }
5102 
5103 static const struct bpf_func_proto bpf_get_netns_cookie_sock_proto = {
5104 	.func		= bpf_get_netns_cookie_sock,
5105 	.gpl_only	= false,
5106 	.ret_type	= RET_INTEGER,
5107 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5108 };
5109 
BPF_CALL_1(bpf_get_netns_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)5110 BPF_CALL_1(bpf_get_netns_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
5111 {
5112 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
5113 }
5114 
5115 static const struct bpf_func_proto bpf_get_netns_cookie_sock_addr_proto = {
5116 	.func		= bpf_get_netns_cookie_sock_addr,
5117 	.gpl_only	= false,
5118 	.ret_type	= RET_INTEGER,
5119 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5120 };
5121 
BPF_CALL_1(bpf_get_netns_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)5122 BPF_CALL_1(bpf_get_netns_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
5123 {
5124 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
5125 }
5126 
5127 static const struct bpf_func_proto bpf_get_netns_cookie_sock_ops_proto = {
5128 	.func		= bpf_get_netns_cookie_sock_ops,
5129 	.gpl_only	= false,
5130 	.ret_type	= RET_INTEGER,
5131 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5132 };
5133 
BPF_CALL_1(bpf_get_netns_cookie_sk_msg,struct sk_msg *,ctx)5134 BPF_CALL_1(bpf_get_netns_cookie_sk_msg, struct sk_msg *, ctx)
5135 {
5136 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
5137 }
5138 
5139 static const struct bpf_func_proto bpf_get_netns_cookie_sk_msg_proto = {
5140 	.func		= bpf_get_netns_cookie_sk_msg,
5141 	.gpl_only	= false,
5142 	.ret_type	= RET_INTEGER,
5143 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5144 };
5145 
BPF_CALL_1(bpf_get_socket_uid,struct sk_buff *,skb)5146 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
5147 {
5148 	struct sock *sk = sk_to_full_sk(skb->sk);
5149 	kuid_t kuid;
5150 
5151 	if (!sk || !sk_fullsock(sk))
5152 		return overflowuid;
5153 	kuid = sock_net_uid(sock_net(sk), sk);
5154 	return from_kuid_munged(sock_net(sk)->user_ns, kuid);
5155 }
5156 
5157 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
5158 	.func           = bpf_get_socket_uid,
5159 	.gpl_only       = false,
5160 	.ret_type       = RET_INTEGER,
5161 	.arg1_type      = ARG_PTR_TO_CTX,
5162 };
5163 
sol_socket_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5164 static int sol_socket_sockopt(struct sock *sk, int optname,
5165 			      char *optval, int *optlen,
5166 			      bool getopt)
5167 {
5168 	switch (optname) {
5169 	case SO_REUSEADDR:
5170 	case SO_SNDBUF:
5171 	case SO_RCVBUF:
5172 	case SO_KEEPALIVE:
5173 	case SO_PRIORITY:
5174 	case SO_REUSEPORT:
5175 	case SO_RCVLOWAT:
5176 	case SO_MARK:
5177 	case SO_MAX_PACING_RATE:
5178 	case SO_BINDTOIFINDEX:
5179 	case SO_TXREHASH:
5180 		if (*optlen != sizeof(int))
5181 			return -EINVAL;
5182 		break;
5183 	case SO_BINDTODEVICE:
5184 		break;
5185 	default:
5186 		return -EINVAL;
5187 	}
5188 
5189 	if (getopt) {
5190 		if (optname == SO_BINDTODEVICE)
5191 			return -EINVAL;
5192 		return sk_getsockopt(sk, SOL_SOCKET, optname,
5193 				     KERNEL_SOCKPTR(optval),
5194 				     KERNEL_SOCKPTR(optlen));
5195 	}
5196 
5197 	return sk_setsockopt(sk, SOL_SOCKET, optname,
5198 			     KERNEL_SOCKPTR(optval), *optlen);
5199 }
5200 
bpf_sol_tcp_setsockopt(struct sock * sk,int optname,char * optval,int optlen)5201 static int bpf_sol_tcp_setsockopt(struct sock *sk, int optname,
5202 				  char *optval, int optlen)
5203 {
5204 	struct tcp_sock *tp = tcp_sk(sk);
5205 	unsigned long timeout;
5206 	int val;
5207 
5208 	if (optlen != sizeof(int))
5209 		return -EINVAL;
5210 
5211 	val = *(int *)optval;
5212 
5213 	/* Only some options are supported */
5214 	switch (optname) {
5215 	case TCP_BPF_IW:
5216 		if (val <= 0 || tp->data_segs_out > tp->syn_data)
5217 			return -EINVAL;
5218 		tcp_snd_cwnd_set(tp, val);
5219 		break;
5220 	case TCP_BPF_SNDCWND_CLAMP:
5221 		if (val <= 0)
5222 			return -EINVAL;
5223 		tp->snd_cwnd_clamp = val;
5224 		tp->snd_ssthresh = val;
5225 		break;
5226 	case TCP_BPF_DELACK_MAX:
5227 		timeout = usecs_to_jiffies(val);
5228 		if (timeout > TCP_DELACK_MAX ||
5229 		    timeout < TCP_TIMEOUT_MIN)
5230 			return -EINVAL;
5231 		inet_csk(sk)->icsk_delack_max = timeout;
5232 		break;
5233 	case TCP_BPF_RTO_MIN:
5234 		timeout = usecs_to_jiffies(val);
5235 		if (timeout > TCP_RTO_MIN ||
5236 		    timeout < TCP_TIMEOUT_MIN)
5237 			return -EINVAL;
5238 		inet_csk(sk)->icsk_rto_min = timeout;
5239 		break;
5240 	default:
5241 		return -EINVAL;
5242 	}
5243 
5244 	return 0;
5245 }
5246 
sol_tcp_sockopt_congestion(struct sock * sk,char * optval,int * optlen,bool getopt)5247 static int sol_tcp_sockopt_congestion(struct sock *sk, char *optval,
5248 				      int *optlen, bool getopt)
5249 {
5250 	struct tcp_sock *tp;
5251 	int ret;
5252 
5253 	if (*optlen < 2)
5254 		return -EINVAL;
5255 
5256 	if (getopt) {
5257 		if (!inet_csk(sk)->icsk_ca_ops)
5258 			return -EINVAL;
5259 		/* BPF expects NULL-terminated tcp-cc string */
5260 		optval[--(*optlen)] = '\0';
5261 		return do_tcp_getsockopt(sk, SOL_TCP, TCP_CONGESTION,
5262 					 KERNEL_SOCKPTR(optval),
5263 					 KERNEL_SOCKPTR(optlen));
5264 	}
5265 
5266 	/* "cdg" is the only cc that alloc a ptr
5267 	 * in inet_csk_ca area.  The bpf-tcp-cc may
5268 	 * overwrite this ptr after switching to cdg.
5269 	 */
5270 	if (*optlen >= sizeof("cdg") - 1 && !strncmp("cdg", optval, *optlen))
5271 		return -ENOTSUPP;
5272 
5273 	/* It stops this looping
5274 	 *
5275 	 * .init => bpf_setsockopt(tcp_cc) => .init =>
5276 	 * bpf_setsockopt(tcp_cc)" => .init => ....
5277 	 *
5278 	 * The second bpf_setsockopt(tcp_cc) is not allowed
5279 	 * in order to break the loop when both .init
5280 	 * are the same bpf prog.
5281 	 *
5282 	 * This applies even the second bpf_setsockopt(tcp_cc)
5283 	 * does not cause a loop.  This limits only the first
5284 	 * '.init' can call bpf_setsockopt(TCP_CONGESTION) to
5285 	 * pick a fallback cc (eg. peer does not support ECN)
5286 	 * and the second '.init' cannot fallback to
5287 	 * another.
5288 	 */
5289 	tp = tcp_sk(sk);
5290 	if (tp->bpf_chg_cc_inprogress)
5291 		return -EBUSY;
5292 
5293 	tp->bpf_chg_cc_inprogress = 1;
5294 	ret = do_tcp_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
5295 				KERNEL_SOCKPTR(optval), *optlen);
5296 	tp->bpf_chg_cc_inprogress = 0;
5297 	return ret;
5298 }
5299 
sol_tcp_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5300 static int sol_tcp_sockopt(struct sock *sk, int optname,
5301 			   char *optval, int *optlen,
5302 			   bool getopt)
5303 {
5304 	if (sk->sk_protocol != IPPROTO_TCP)
5305 		return -EINVAL;
5306 
5307 	switch (optname) {
5308 	case TCP_NODELAY:
5309 	case TCP_MAXSEG:
5310 	case TCP_KEEPIDLE:
5311 	case TCP_KEEPINTVL:
5312 	case TCP_KEEPCNT:
5313 	case TCP_SYNCNT:
5314 	case TCP_WINDOW_CLAMP:
5315 	case TCP_THIN_LINEAR_TIMEOUTS:
5316 	case TCP_USER_TIMEOUT:
5317 	case TCP_NOTSENT_LOWAT:
5318 	case TCP_SAVE_SYN:
5319 		if (*optlen != sizeof(int))
5320 			return -EINVAL;
5321 		break;
5322 	case TCP_CONGESTION:
5323 		return sol_tcp_sockopt_congestion(sk, optval, optlen, getopt);
5324 	case TCP_SAVED_SYN:
5325 		if (*optlen < 1)
5326 			return -EINVAL;
5327 		break;
5328 	default:
5329 		if (getopt)
5330 			return -EINVAL;
5331 		return bpf_sol_tcp_setsockopt(sk, optname, optval, *optlen);
5332 	}
5333 
5334 	if (getopt) {
5335 		if (optname == TCP_SAVED_SYN) {
5336 			struct tcp_sock *tp = tcp_sk(sk);
5337 
5338 			if (!tp->saved_syn ||
5339 			    *optlen > tcp_saved_syn_len(tp->saved_syn))
5340 				return -EINVAL;
5341 			memcpy(optval, tp->saved_syn->data, *optlen);
5342 			/* It cannot free tp->saved_syn here because it
5343 			 * does not know if the user space still needs it.
5344 			 */
5345 			return 0;
5346 		}
5347 
5348 		return do_tcp_getsockopt(sk, SOL_TCP, optname,
5349 					 KERNEL_SOCKPTR(optval),
5350 					 KERNEL_SOCKPTR(optlen));
5351 	}
5352 
5353 	return do_tcp_setsockopt(sk, SOL_TCP, optname,
5354 				 KERNEL_SOCKPTR(optval), *optlen);
5355 }
5356 
sol_ip_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5357 static int sol_ip_sockopt(struct sock *sk, int optname,
5358 			  char *optval, int *optlen,
5359 			  bool getopt)
5360 {
5361 	if (sk->sk_family != AF_INET)
5362 		return -EINVAL;
5363 
5364 	switch (optname) {
5365 	case IP_TOS:
5366 		if (*optlen != sizeof(int))
5367 			return -EINVAL;
5368 		break;
5369 	default:
5370 		return -EINVAL;
5371 	}
5372 
5373 	if (getopt)
5374 		return do_ip_getsockopt(sk, SOL_IP, optname,
5375 					KERNEL_SOCKPTR(optval),
5376 					KERNEL_SOCKPTR(optlen));
5377 
5378 	return do_ip_setsockopt(sk, SOL_IP, optname,
5379 				KERNEL_SOCKPTR(optval), *optlen);
5380 }
5381 
sol_ipv6_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5382 static int sol_ipv6_sockopt(struct sock *sk, int optname,
5383 			    char *optval, int *optlen,
5384 			    bool getopt)
5385 {
5386 	if (sk->sk_family != AF_INET6)
5387 		return -EINVAL;
5388 
5389 	switch (optname) {
5390 	case IPV6_TCLASS:
5391 	case IPV6_AUTOFLOWLABEL:
5392 		if (*optlen != sizeof(int))
5393 			return -EINVAL;
5394 		break;
5395 	default:
5396 		return -EINVAL;
5397 	}
5398 
5399 	if (getopt)
5400 		return ipv6_bpf_stub->ipv6_getsockopt(sk, SOL_IPV6, optname,
5401 						      KERNEL_SOCKPTR(optval),
5402 						      KERNEL_SOCKPTR(optlen));
5403 
5404 	return ipv6_bpf_stub->ipv6_setsockopt(sk, SOL_IPV6, optname,
5405 					      KERNEL_SOCKPTR(optval), *optlen);
5406 }
5407 
__bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5408 static int __bpf_setsockopt(struct sock *sk, int level, int optname,
5409 			    char *optval, int optlen)
5410 {
5411 	if (!sk_fullsock(sk))
5412 		return -EINVAL;
5413 
5414 	if (level == SOL_SOCKET)
5415 		return sol_socket_sockopt(sk, optname, optval, &optlen, false);
5416 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
5417 		return sol_ip_sockopt(sk, optname, optval, &optlen, false);
5418 	else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
5419 		return sol_ipv6_sockopt(sk, optname, optval, &optlen, false);
5420 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
5421 		return sol_tcp_sockopt(sk, optname, optval, &optlen, false);
5422 
5423 	return -EINVAL;
5424 }
5425 
_bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5426 static int _bpf_setsockopt(struct sock *sk, int level, int optname,
5427 			   char *optval, int optlen)
5428 {
5429 	if (sk_fullsock(sk))
5430 		sock_owned_by_me(sk);
5431 	return __bpf_setsockopt(sk, level, optname, optval, optlen);
5432 }
5433 
__bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5434 static int __bpf_getsockopt(struct sock *sk, int level, int optname,
5435 			    char *optval, int optlen)
5436 {
5437 	int err, saved_optlen = optlen;
5438 
5439 	if (!sk_fullsock(sk)) {
5440 		err = -EINVAL;
5441 		goto done;
5442 	}
5443 
5444 	if (level == SOL_SOCKET)
5445 		err = sol_socket_sockopt(sk, optname, optval, &optlen, true);
5446 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
5447 		err = sol_tcp_sockopt(sk, optname, optval, &optlen, true);
5448 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
5449 		err = sol_ip_sockopt(sk, optname, optval, &optlen, true);
5450 	else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
5451 		err = sol_ipv6_sockopt(sk, optname, optval, &optlen, true);
5452 	else
5453 		err = -EINVAL;
5454 
5455 done:
5456 	if (err)
5457 		optlen = 0;
5458 	if (optlen < saved_optlen)
5459 		memset(optval + optlen, 0, saved_optlen - optlen);
5460 	return err;
5461 }
5462 
_bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5463 static int _bpf_getsockopt(struct sock *sk, int level, int optname,
5464 			   char *optval, int optlen)
5465 {
5466 	if (sk_fullsock(sk))
5467 		sock_owned_by_me(sk);
5468 	return __bpf_getsockopt(sk, level, optname, optval, optlen);
5469 }
5470 
BPF_CALL_5(bpf_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5471 BPF_CALL_5(bpf_sk_setsockopt, struct sock *, sk, int, level,
5472 	   int, optname, char *, optval, int, optlen)
5473 {
5474 	return _bpf_setsockopt(sk, level, optname, optval, optlen);
5475 }
5476 
5477 const struct bpf_func_proto bpf_sk_setsockopt_proto = {
5478 	.func		= bpf_sk_setsockopt,
5479 	.gpl_only	= false,
5480 	.ret_type	= RET_INTEGER,
5481 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5482 	.arg2_type	= ARG_ANYTHING,
5483 	.arg3_type	= ARG_ANYTHING,
5484 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5485 	.arg5_type	= ARG_CONST_SIZE,
5486 };
5487 
BPF_CALL_5(bpf_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5488 BPF_CALL_5(bpf_sk_getsockopt, struct sock *, sk, int, level,
5489 	   int, optname, char *, optval, int, optlen)
5490 {
5491 	return _bpf_getsockopt(sk, level, optname, optval, optlen);
5492 }
5493 
5494 const struct bpf_func_proto bpf_sk_getsockopt_proto = {
5495 	.func		= bpf_sk_getsockopt,
5496 	.gpl_only	= false,
5497 	.ret_type	= RET_INTEGER,
5498 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5499 	.arg2_type	= ARG_ANYTHING,
5500 	.arg3_type	= ARG_ANYTHING,
5501 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5502 	.arg5_type	= ARG_CONST_SIZE,
5503 };
5504 
BPF_CALL_5(bpf_unlocked_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5505 BPF_CALL_5(bpf_unlocked_sk_setsockopt, struct sock *, sk, int, level,
5506 	   int, optname, char *, optval, int, optlen)
5507 {
5508 	return __bpf_setsockopt(sk, level, optname, optval, optlen);
5509 }
5510 
5511 const struct bpf_func_proto bpf_unlocked_sk_setsockopt_proto = {
5512 	.func		= bpf_unlocked_sk_setsockopt,
5513 	.gpl_only	= false,
5514 	.ret_type	= RET_INTEGER,
5515 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5516 	.arg2_type	= ARG_ANYTHING,
5517 	.arg3_type	= ARG_ANYTHING,
5518 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5519 	.arg5_type	= ARG_CONST_SIZE,
5520 };
5521 
BPF_CALL_5(bpf_unlocked_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5522 BPF_CALL_5(bpf_unlocked_sk_getsockopt, struct sock *, sk, int, level,
5523 	   int, optname, char *, optval, int, optlen)
5524 {
5525 	return __bpf_getsockopt(sk, level, optname, optval, optlen);
5526 }
5527 
5528 const struct bpf_func_proto bpf_unlocked_sk_getsockopt_proto = {
5529 	.func		= bpf_unlocked_sk_getsockopt,
5530 	.gpl_only	= false,
5531 	.ret_type	= RET_INTEGER,
5532 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5533 	.arg2_type	= ARG_ANYTHING,
5534 	.arg3_type	= ARG_ANYTHING,
5535 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5536 	.arg5_type	= ARG_CONST_SIZE,
5537 };
5538 
BPF_CALL_5(bpf_sock_addr_setsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5539 BPF_CALL_5(bpf_sock_addr_setsockopt, struct bpf_sock_addr_kern *, ctx,
5540 	   int, level, int, optname, char *, optval, int, optlen)
5541 {
5542 	return _bpf_setsockopt(ctx->sk, level, optname, optval, optlen);
5543 }
5544 
5545 static const struct bpf_func_proto bpf_sock_addr_setsockopt_proto = {
5546 	.func		= bpf_sock_addr_setsockopt,
5547 	.gpl_only	= false,
5548 	.ret_type	= RET_INTEGER,
5549 	.arg1_type	= ARG_PTR_TO_CTX,
5550 	.arg2_type	= ARG_ANYTHING,
5551 	.arg3_type	= ARG_ANYTHING,
5552 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5553 	.arg5_type	= ARG_CONST_SIZE,
5554 };
5555 
BPF_CALL_5(bpf_sock_addr_getsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5556 BPF_CALL_5(bpf_sock_addr_getsockopt, struct bpf_sock_addr_kern *, ctx,
5557 	   int, level, int, optname, char *, optval, int, optlen)
5558 {
5559 	return _bpf_getsockopt(ctx->sk, level, optname, optval, optlen);
5560 }
5561 
5562 static const struct bpf_func_proto bpf_sock_addr_getsockopt_proto = {
5563 	.func		= bpf_sock_addr_getsockopt,
5564 	.gpl_only	= false,
5565 	.ret_type	= RET_INTEGER,
5566 	.arg1_type	= ARG_PTR_TO_CTX,
5567 	.arg2_type	= ARG_ANYTHING,
5568 	.arg3_type	= ARG_ANYTHING,
5569 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5570 	.arg5_type	= ARG_CONST_SIZE,
5571 };
5572 
BPF_CALL_5(bpf_sock_ops_setsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5573 BPF_CALL_5(bpf_sock_ops_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5574 	   int, level, int, optname, char *, optval, int, optlen)
5575 {
5576 	return _bpf_setsockopt(bpf_sock->sk, level, optname, optval, optlen);
5577 }
5578 
5579 static const struct bpf_func_proto bpf_sock_ops_setsockopt_proto = {
5580 	.func		= bpf_sock_ops_setsockopt,
5581 	.gpl_only	= false,
5582 	.ret_type	= RET_INTEGER,
5583 	.arg1_type	= ARG_PTR_TO_CTX,
5584 	.arg2_type	= ARG_ANYTHING,
5585 	.arg3_type	= ARG_ANYTHING,
5586 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5587 	.arg5_type	= ARG_CONST_SIZE,
5588 };
5589 
bpf_sock_ops_get_syn(struct bpf_sock_ops_kern * bpf_sock,int optname,const u8 ** start)5590 static int bpf_sock_ops_get_syn(struct bpf_sock_ops_kern *bpf_sock,
5591 				int optname, const u8 **start)
5592 {
5593 	struct sk_buff *syn_skb = bpf_sock->syn_skb;
5594 	const u8 *hdr_start;
5595 	int ret;
5596 
5597 	if (syn_skb) {
5598 		/* sk is a request_sock here */
5599 
5600 		if (optname == TCP_BPF_SYN) {
5601 			hdr_start = syn_skb->data;
5602 			ret = tcp_hdrlen(syn_skb);
5603 		} else if (optname == TCP_BPF_SYN_IP) {
5604 			hdr_start = skb_network_header(syn_skb);
5605 			ret = skb_network_header_len(syn_skb) +
5606 				tcp_hdrlen(syn_skb);
5607 		} else {
5608 			/* optname == TCP_BPF_SYN_MAC */
5609 			hdr_start = skb_mac_header(syn_skb);
5610 			ret = skb_mac_header_len(syn_skb) +
5611 				skb_network_header_len(syn_skb) +
5612 				tcp_hdrlen(syn_skb);
5613 		}
5614 	} else {
5615 		struct sock *sk = bpf_sock->sk;
5616 		struct saved_syn *saved_syn;
5617 
5618 		if (sk->sk_state == TCP_NEW_SYN_RECV)
5619 			/* synack retransmit. bpf_sock->syn_skb will
5620 			 * not be available.  It has to resort to
5621 			 * saved_syn (if it is saved).
5622 			 */
5623 			saved_syn = inet_reqsk(sk)->saved_syn;
5624 		else
5625 			saved_syn = tcp_sk(sk)->saved_syn;
5626 
5627 		if (!saved_syn)
5628 			return -ENOENT;
5629 
5630 		if (optname == TCP_BPF_SYN) {
5631 			hdr_start = saved_syn->data +
5632 				saved_syn->mac_hdrlen +
5633 				saved_syn->network_hdrlen;
5634 			ret = saved_syn->tcp_hdrlen;
5635 		} else if (optname == TCP_BPF_SYN_IP) {
5636 			hdr_start = saved_syn->data +
5637 				saved_syn->mac_hdrlen;
5638 			ret = saved_syn->network_hdrlen +
5639 				saved_syn->tcp_hdrlen;
5640 		} else {
5641 			/* optname == TCP_BPF_SYN_MAC */
5642 
5643 			/* TCP_SAVE_SYN may not have saved the mac hdr */
5644 			if (!saved_syn->mac_hdrlen)
5645 				return -ENOENT;
5646 
5647 			hdr_start = saved_syn->data;
5648 			ret = saved_syn->mac_hdrlen +
5649 				saved_syn->network_hdrlen +
5650 				saved_syn->tcp_hdrlen;
5651 		}
5652 	}
5653 
5654 	*start = hdr_start;
5655 	return ret;
5656 }
5657 
BPF_CALL_5(bpf_sock_ops_getsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5658 BPF_CALL_5(bpf_sock_ops_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5659 	   int, level, int, optname, char *, optval, int, optlen)
5660 {
5661 	if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP &&
5662 	    optname >= TCP_BPF_SYN && optname <= TCP_BPF_SYN_MAC) {
5663 		int ret, copy_len = 0;
5664 		const u8 *start;
5665 
5666 		ret = bpf_sock_ops_get_syn(bpf_sock, optname, &start);
5667 		if (ret > 0) {
5668 			copy_len = ret;
5669 			if (optlen < copy_len) {
5670 				copy_len = optlen;
5671 				ret = -ENOSPC;
5672 			}
5673 
5674 			memcpy(optval, start, copy_len);
5675 		}
5676 
5677 		/* Zero out unused buffer at the end */
5678 		memset(optval + copy_len, 0, optlen - copy_len);
5679 
5680 		return ret;
5681 	}
5682 
5683 	return _bpf_getsockopt(bpf_sock->sk, level, optname, optval, optlen);
5684 }
5685 
5686 static const struct bpf_func_proto bpf_sock_ops_getsockopt_proto = {
5687 	.func		= bpf_sock_ops_getsockopt,
5688 	.gpl_only	= false,
5689 	.ret_type	= RET_INTEGER,
5690 	.arg1_type	= ARG_PTR_TO_CTX,
5691 	.arg2_type	= ARG_ANYTHING,
5692 	.arg3_type	= ARG_ANYTHING,
5693 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5694 	.arg5_type	= ARG_CONST_SIZE,
5695 };
5696 
BPF_CALL_2(bpf_sock_ops_cb_flags_set,struct bpf_sock_ops_kern *,bpf_sock,int,argval)5697 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
5698 	   int, argval)
5699 {
5700 	struct sock *sk = bpf_sock->sk;
5701 	int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
5702 
5703 	if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
5704 		return -EINVAL;
5705 
5706 	tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
5707 
5708 	return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
5709 }
5710 
5711 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
5712 	.func		= bpf_sock_ops_cb_flags_set,
5713 	.gpl_only	= false,
5714 	.ret_type	= RET_INTEGER,
5715 	.arg1_type	= ARG_PTR_TO_CTX,
5716 	.arg2_type	= ARG_ANYTHING,
5717 };
5718 
5719 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
5720 EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
5721 
BPF_CALL_3(bpf_bind,struct bpf_sock_addr_kern *,ctx,struct sockaddr *,addr,int,addr_len)5722 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
5723 	   int, addr_len)
5724 {
5725 #ifdef CONFIG_INET
5726 	struct sock *sk = ctx->sk;
5727 	u32 flags = BIND_FROM_BPF;
5728 	int err;
5729 
5730 	err = -EINVAL;
5731 	if (addr_len < offsetofend(struct sockaddr, sa_family))
5732 		return err;
5733 	if (addr->sa_family == AF_INET) {
5734 		if (addr_len < sizeof(struct sockaddr_in))
5735 			return err;
5736 		if (((struct sockaddr_in *)addr)->sin_port == htons(0))
5737 			flags |= BIND_FORCE_ADDRESS_NO_PORT;
5738 		return __inet_bind(sk, addr, addr_len, flags);
5739 #if IS_ENABLED(CONFIG_IPV6)
5740 	} else if (addr->sa_family == AF_INET6) {
5741 		if (addr_len < SIN6_LEN_RFC2133)
5742 			return err;
5743 		if (((struct sockaddr_in6 *)addr)->sin6_port == htons(0))
5744 			flags |= BIND_FORCE_ADDRESS_NO_PORT;
5745 		/* ipv6_bpf_stub cannot be NULL, since it's called from
5746 		 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded
5747 		 */
5748 		return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, flags);
5749 #endif /* CONFIG_IPV6 */
5750 	}
5751 #endif /* CONFIG_INET */
5752 
5753 	return -EAFNOSUPPORT;
5754 }
5755 
5756 static const struct bpf_func_proto bpf_bind_proto = {
5757 	.func		= bpf_bind,
5758 	.gpl_only	= false,
5759 	.ret_type	= RET_INTEGER,
5760 	.arg1_type	= ARG_PTR_TO_CTX,
5761 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5762 	.arg3_type	= ARG_CONST_SIZE,
5763 };
5764 
5765 #ifdef CONFIG_XFRM
5766 
5767 #if (IS_BUILTIN(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \
5768     (IS_MODULE(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))
5769 
5770 struct metadata_dst __percpu *xfrm_bpf_md_dst;
5771 EXPORT_SYMBOL_GPL(xfrm_bpf_md_dst);
5772 
5773 #endif
5774 
BPF_CALL_5(bpf_skb_get_xfrm_state,struct sk_buff *,skb,u32,index,struct bpf_xfrm_state *,to,u32,size,u64,flags)5775 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
5776 	   struct bpf_xfrm_state *, to, u32, size, u64, flags)
5777 {
5778 	const struct sec_path *sp = skb_sec_path(skb);
5779 	const struct xfrm_state *x;
5780 
5781 	if (!sp || unlikely(index >= sp->len || flags))
5782 		goto err_clear;
5783 
5784 	x = sp->xvec[index];
5785 
5786 	if (unlikely(size != sizeof(struct bpf_xfrm_state)))
5787 		goto err_clear;
5788 
5789 	to->reqid = x->props.reqid;
5790 	to->spi = x->id.spi;
5791 	to->family = x->props.family;
5792 	to->ext = 0;
5793 
5794 	if (to->family == AF_INET6) {
5795 		memcpy(to->remote_ipv6, x->props.saddr.a6,
5796 		       sizeof(to->remote_ipv6));
5797 	} else {
5798 		to->remote_ipv4 = x->props.saddr.a4;
5799 		memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
5800 	}
5801 
5802 	return 0;
5803 err_clear:
5804 	memset(to, 0, size);
5805 	return -EINVAL;
5806 }
5807 
5808 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
5809 	.func		= bpf_skb_get_xfrm_state,
5810 	.gpl_only	= false,
5811 	.ret_type	= RET_INTEGER,
5812 	.arg1_type	= ARG_PTR_TO_CTX,
5813 	.arg2_type	= ARG_ANYTHING,
5814 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
5815 	.arg4_type	= ARG_CONST_SIZE,
5816 	.arg5_type	= ARG_ANYTHING,
5817 };
5818 #endif
5819 
5820 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6)
bpf_fib_set_fwd_params(struct bpf_fib_lookup * params,u32 mtu)5821 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, u32 mtu)
5822 {
5823 	params->h_vlan_TCI = 0;
5824 	params->h_vlan_proto = 0;
5825 	if (mtu)
5826 		params->mtu_result = mtu; /* union with tot_len */
5827 
5828 	return 0;
5829 }
5830 #endif
5831 
5832 #if IS_ENABLED(CONFIG_INET)
bpf_ipv4_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5833 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5834 			       u32 flags, bool check_mtu)
5835 {
5836 	struct fib_nh_common *nhc;
5837 	struct in_device *in_dev;
5838 	struct neighbour *neigh;
5839 	struct net_device *dev;
5840 	struct fib_result res;
5841 	struct flowi4 fl4;
5842 	u32 mtu = 0;
5843 	int err;
5844 
5845 	dev = dev_get_by_index_rcu(net, params->ifindex);
5846 	if (unlikely(!dev))
5847 		return -ENODEV;
5848 
5849 	/* verify forwarding is enabled on this interface */
5850 	in_dev = __in_dev_get_rcu(dev);
5851 	if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
5852 		return BPF_FIB_LKUP_RET_FWD_DISABLED;
5853 
5854 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5855 		fl4.flowi4_iif = 1;
5856 		fl4.flowi4_oif = params->ifindex;
5857 	} else {
5858 		fl4.flowi4_iif = params->ifindex;
5859 		fl4.flowi4_oif = 0;
5860 	}
5861 	fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
5862 	fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
5863 	fl4.flowi4_flags = 0;
5864 
5865 	fl4.flowi4_proto = params->l4_protocol;
5866 	fl4.daddr = params->ipv4_dst;
5867 	fl4.saddr = params->ipv4_src;
5868 	fl4.fl4_sport = params->sport;
5869 	fl4.fl4_dport = params->dport;
5870 	fl4.flowi4_multipath_hash = 0;
5871 
5872 	if (flags & BPF_FIB_LOOKUP_DIRECT) {
5873 		u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5874 		struct fib_table *tb;
5875 
5876 		if (flags & BPF_FIB_LOOKUP_TBID) {
5877 			tbid = params->tbid;
5878 			/* zero out for vlan output */
5879 			params->tbid = 0;
5880 		}
5881 
5882 		tb = fib_get_table(net, tbid);
5883 		if (unlikely(!tb))
5884 			return BPF_FIB_LKUP_RET_NOT_FWDED;
5885 
5886 		err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
5887 	} else {
5888 		fl4.flowi4_mark = 0;
5889 		fl4.flowi4_secid = 0;
5890 		fl4.flowi4_tun_key.tun_id = 0;
5891 		fl4.flowi4_uid = sock_net_uid(net, NULL);
5892 
5893 		err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
5894 	}
5895 
5896 	if (err) {
5897 		/* map fib lookup errors to RTN_ type */
5898 		if (err == -EINVAL)
5899 			return BPF_FIB_LKUP_RET_BLACKHOLE;
5900 		if (err == -EHOSTUNREACH)
5901 			return BPF_FIB_LKUP_RET_UNREACHABLE;
5902 		if (err == -EACCES)
5903 			return BPF_FIB_LKUP_RET_PROHIBIT;
5904 
5905 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5906 	}
5907 
5908 	if (res.type != RTN_UNICAST)
5909 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5910 
5911 	if (fib_info_num_path(res.fi) > 1)
5912 		fib_select_path(net, &res, &fl4, NULL);
5913 
5914 	if (check_mtu) {
5915 		mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
5916 		if (params->tot_len > mtu) {
5917 			params->mtu_result = mtu; /* union with tot_len */
5918 			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5919 		}
5920 	}
5921 
5922 	nhc = res.nhc;
5923 
5924 	/* do not handle lwt encaps right now */
5925 	if (nhc->nhc_lwtstate)
5926 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5927 
5928 	dev = nhc->nhc_dev;
5929 
5930 	params->rt_metric = res.fi->fib_priority;
5931 	params->ifindex = dev->ifindex;
5932 
5933 	if (flags & BPF_FIB_LOOKUP_SRC)
5934 		params->ipv4_src = fib_result_prefsrc(net, &res);
5935 
5936 	/* xdp and cls_bpf programs are run in RCU-bh so
5937 	 * rcu_read_lock_bh is not needed here
5938 	 */
5939 	if (likely(nhc->nhc_gw_family != AF_INET6)) {
5940 		if (nhc->nhc_gw_family)
5941 			params->ipv4_dst = nhc->nhc_gw.ipv4;
5942 	} else {
5943 		struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;
5944 
5945 		params->family = AF_INET6;
5946 		*dst = nhc->nhc_gw.ipv6;
5947 	}
5948 
5949 	if (flags & BPF_FIB_LOOKUP_SKIP_NEIGH)
5950 		goto set_fwd_params;
5951 
5952 	if (likely(nhc->nhc_gw_family != AF_INET6))
5953 		neigh = __ipv4_neigh_lookup_noref(dev,
5954 						  (__force u32)params->ipv4_dst);
5955 	else
5956 		neigh = __ipv6_neigh_lookup_noref_stub(dev, params->ipv6_dst);
5957 
5958 	if (!neigh || !(READ_ONCE(neigh->nud_state) & NUD_VALID))
5959 		return BPF_FIB_LKUP_RET_NO_NEIGH;
5960 	memcpy(params->dmac, neigh->ha, ETH_ALEN);
5961 	memcpy(params->smac, dev->dev_addr, ETH_ALEN);
5962 
5963 set_fwd_params:
5964 	return bpf_fib_set_fwd_params(params, mtu);
5965 }
5966 #endif
5967 
5968 #if IS_ENABLED(CONFIG_IPV6)
bpf_ipv6_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5969 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5970 			       u32 flags, bool check_mtu)
5971 {
5972 	struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
5973 	struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
5974 	struct fib6_result res = {};
5975 	struct neighbour *neigh;
5976 	struct net_device *dev;
5977 	struct inet6_dev *idev;
5978 	struct flowi6 fl6;
5979 	int strict = 0;
5980 	int oif, err;
5981 	u32 mtu = 0;
5982 
5983 	/* link local addresses are never forwarded */
5984 	if (rt6_need_strict(dst) || rt6_need_strict(src))
5985 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5986 
5987 	dev = dev_get_by_index_rcu(net, params->ifindex);
5988 	if (unlikely(!dev))
5989 		return -ENODEV;
5990 
5991 	idev = __in6_dev_get_safely(dev);
5992 	if (unlikely(!idev || !idev->cnf.forwarding))
5993 		return BPF_FIB_LKUP_RET_FWD_DISABLED;
5994 
5995 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5996 		fl6.flowi6_iif = 1;
5997 		oif = fl6.flowi6_oif = params->ifindex;
5998 	} else {
5999 		oif = fl6.flowi6_iif = params->ifindex;
6000 		fl6.flowi6_oif = 0;
6001 		strict = RT6_LOOKUP_F_HAS_SADDR;
6002 	}
6003 	fl6.flowlabel = params->flowinfo;
6004 	fl6.flowi6_scope = 0;
6005 	fl6.flowi6_flags = 0;
6006 	fl6.mp_hash = 0;
6007 
6008 	fl6.flowi6_proto = params->l4_protocol;
6009 	fl6.daddr = *dst;
6010 	fl6.saddr = *src;
6011 	fl6.fl6_sport = params->sport;
6012 	fl6.fl6_dport = params->dport;
6013 
6014 	if (flags & BPF_FIB_LOOKUP_DIRECT) {
6015 		u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
6016 		struct fib6_table *tb;
6017 
6018 		if (flags & BPF_FIB_LOOKUP_TBID) {
6019 			tbid = params->tbid;
6020 			/* zero out for vlan output */
6021 			params->tbid = 0;
6022 		}
6023 
6024 		tb = ipv6_stub->fib6_get_table(net, tbid);
6025 		if (unlikely(!tb))
6026 			return BPF_FIB_LKUP_RET_NOT_FWDED;
6027 
6028 		err = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, &res,
6029 						   strict);
6030 	} else {
6031 		fl6.flowi6_mark = 0;
6032 		fl6.flowi6_secid = 0;
6033 		fl6.flowi6_tun_key.tun_id = 0;
6034 		fl6.flowi6_uid = sock_net_uid(net, NULL);
6035 
6036 		err = ipv6_stub->fib6_lookup(net, oif, &fl6, &res, strict);
6037 	}
6038 
6039 	if (unlikely(err || IS_ERR_OR_NULL(res.f6i) ||
6040 		     res.f6i == net->ipv6.fib6_null_entry))
6041 		return BPF_FIB_LKUP_RET_NOT_FWDED;
6042 
6043 	switch (res.fib6_type) {
6044 	/* only unicast is forwarded */
6045 	case RTN_UNICAST:
6046 		break;
6047 	case RTN_BLACKHOLE:
6048 		return BPF_FIB_LKUP_RET_BLACKHOLE;
6049 	case RTN_UNREACHABLE:
6050 		return BPF_FIB_LKUP_RET_UNREACHABLE;
6051 	case RTN_PROHIBIT:
6052 		return BPF_FIB_LKUP_RET_PROHIBIT;
6053 	default:
6054 		return BPF_FIB_LKUP_RET_NOT_FWDED;
6055 	}
6056 
6057 	ipv6_stub->fib6_select_path(net, &res, &fl6, fl6.flowi6_oif,
6058 				    fl6.flowi6_oif != 0, NULL, strict);
6059 
6060 	if (check_mtu) {
6061 		mtu = ipv6_stub->ip6_mtu_from_fib6(&res, dst, src);
6062 		if (params->tot_len > mtu) {
6063 			params->mtu_result = mtu; /* union with tot_len */
6064 			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
6065 		}
6066 	}
6067 
6068 	if (res.nh->fib_nh_lws)
6069 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
6070 
6071 	if (res.nh->fib_nh_gw_family)
6072 		*dst = res.nh->fib_nh_gw6;
6073 
6074 	dev = res.nh->fib_nh_dev;
6075 	params->rt_metric = res.f6i->fib6_metric;
6076 	params->ifindex = dev->ifindex;
6077 
6078 	if (flags & BPF_FIB_LOOKUP_SRC) {
6079 		if (res.f6i->fib6_prefsrc.plen) {
6080 			*src = res.f6i->fib6_prefsrc.addr;
6081 		} else {
6082 			err = ipv6_bpf_stub->ipv6_dev_get_saddr(net, dev,
6083 								&fl6.daddr, 0,
6084 								src);
6085 			if (err)
6086 				return BPF_FIB_LKUP_RET_NO_SRC_ADDR;
6087 		}
6088 	}
6089 
6090 	if (flags & BPF_FIB_LOOKUP_SKIP_NEIGH)
6091 		goto set_fwd_params;
6092 
6093 	/* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
6094 	 * not needed here.
6095 	 */
6096 	neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
6097 	if (!neigh || !(READ_ONCE(neigh->nud_state) & NUD_VALID))
6098 		return BPF_FIB_LKUP_RET_NO_NEIGH;
6099 	memcpy(params->dmac, neigh->ha, ETH_ALEN);
6100 	memcpy(params->smac, dev->dev_addr, ETH_ALEN);
6101 
6102 set_fwd_params:
6103 	return bpf_fib_set_fwd_params(params, mtu);
6104 }
6105 #endif
6106 
6107 #define BPF_FIB_LOOKUP_MASK (BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT | \
6108 			     BPF_FIB_LOOKUP_SKIP_NEIGH | BPF_FIB_LOOKUP_TBID | \
6109 			     BPF_FIB_LOOKUP_SRC)
6110 
BPF_CALL_4(bpf_xdp_fib_lookup,struct xdp_buff *,ctx,struct bpf_fib_lookup *,params,int,plen,u32,flags)6111 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
6112 	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
6113 {
6114 	if (plen < sizeof(*params))
6115 		return -EINVAL;
6116 
6117 	if (flags & ~BPF_FIB_LOOKUP_MASK)
6118 		return -EINVAL;
6119 
6120 	switch (params->family) {
6121 #if IS_ENABLED(CONFIG_INET)
6122 	case AF_INET:
6123 		return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
6124 					   flags, true);
6125 #endif
6126 #if IS_ENABLED(CONFIG_IPV6)
6127 	case AF_INET6:
6128 		return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
6129 					   flags, true);
6130 #endif
6131 	}
6132 	return -EAFNOSUPPORT;
6133 }
6134 
6135 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
6136 	.func		= bpf_xdp_fib_lookup,
6137 	.gpl_only	= true,
6138 	.ret_type	= RET_INTEGER,
6139 	.arg1_type      = ARG_PTR_TO_CTX,
6140 	.arg2_type      = ARG_PTR_TO_MEM,
6141 	.arg3_type      = ARG_CONST_SIZE,
6142 	.arg4_type	= ARG_ANYTHING,
6143 };
6144 
BPF_CALL_4(bpf_skb_fib_lookup,struct sk_buff *,skb,struct bpf_fib_lookup *,params,int,plen,u32,flags)6145 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
6146 	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
6147 {
6148 	struct net *net = dev_net(skb->dev);
6149 	int rc = -EAFNOSUPPORT;
6150 	bool check_mtu = false;
6151 
6152 	if (plen < sizeof(*params))
6153 		return -EINVAL;
6154 
6155 	if (flags & ~BPF_FIB_LOOKUP_MASK)
6156 		return -EINVAL;
6157 
6158 	if (params->tot_len)
6159 		check_mtu = true;
6160 
6161 	switch (params->family) {
6162 #if IS_ENABLED(CONFIG_INET)
6163 	case AF_INET:
6164 		rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu);
6165 		break;
6166 #endif
6167 #if IS_ENABLED(CONFIG_IPV6)
6168 	case AF_INET6:
6169 		rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu);
6170 		break;
6171 #endif
6172 	}
6173 
6174 	if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) {
6175 		struct net_device *dev;
6176 
6177 		/* When tot_len isn't provided by user, check skb
6178 		 * against MTU of FIB lookup resulting net_device
6179 		 */
6180 		dev = dev_get_by_index_rcu(net, params->ifindex);
6181 		if (!is_skb_forwardable(dev, skb))
6182 			rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
6183 
6184 		params->mtu_result = dev->mtu; /* union with tot_len */
6185 	}
6186 
6187 	return rc;
6188 }
6189 
6190 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
6191 	.func		= bpf_skb_fib_lookup,
6192 	.gpl_only	= true,
6193 	.ret_type	= RET_INTEGER,
6194 	.arg1_type      = ARG_PTR_TO_CTX,
6195 	.arg2_type      = ARG_PTR_TO_MEM,
6196 	.arg3_type      = ARG_CONST_SIZE,
6197 	.arg4_type	= ARG_ANYTHING,
6198 };
6199 
__dev_via_ifindex(struct net_device * dev_curr,u32 ifindex)6200 static struct net_device *__dev_via_ifindex(struct net_device *dev_curr,
6201 					    u32 ifindex)
6202 {
6203 	struct net *netns = dev_net(dev_curr);
6204 
6205 	/* Non-redirect use-cases can use ifindex=0 and save ifindex lookup */
6206 	if (ifindex == 0)
6207 		return dev_curr;
6208 
6209 	return dev_get_by_index_rcu(netns, ifindex);
6210 }
6211 
BPF_CALL_5(bpf_skb_check_mtu,struct sk_buff *,skb,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6212 BPF_CALL_5(bpf_skb_check_mtu, struct sk_buff *, skb,
6213 	   u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6214 {
6215 	int ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6216 	struct net_device *dev = skb->dev;
6217 	int skb_len, dev_len;
6218 	int mtu;
6219 
6220 	if (unlikely(flags & ~(BPF_MTU_CHK_SEGS)))
6221 		return -EINVAL;
6222 
6223 	if (unlikely(flags & BPF_MTU_CHK_SEGS && (len_diff || *mtu_len)))
6224 		return -EINVAL;
6225 
6226 	dev = __dev_via_ifindex(dev, ifindex);
6227 	if (unlikely(!dev))
6228 		return -ENODEV;
6229 
6230 	mtu = READ_ONCE(dev->mtu);
6231 
6232 	dev_len = mtu + dev->hard_header_len;
6233 
6234 	/* If set use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6235 	skb_len = *mtu_len ? *mtu_len + dev->hard_header_len : skb->len;
6236 
6237 	skb_len += len_diff; /* minus result pass check */
6238 	if (skb_len <= dev_len) {
6239 		ret = BPF_MTU_CHK_RET_SUCCESS;
6240 		goto out;
6241 	}
6242 	/* At this point, skb->len exceed MTU, but as it include length of all
6243 	 * segments, it can still be below MTU.  The SKB can possibly get
6244 	 * re-segmented in transmit path (see validate_xmit_skb).  Thus, user
6245 	 * must choose if segs are to be MTU checked.
6246 	 */
6247 	if (skb_is_gso(skb)) {
6248 		ret = BPF_MTU_CHK_RET_SUCCESS;
6249 
6250 		if (flags & BPF_MTU_CHK_SEGS &&
6251 		    !skb_gso_validate_network_len(skb, mtu))
6252 			ret = BPF_MTU_CHK_RET_SEGS_TOOBIG;
6253 	}
6254 out:
6255 	/* BPF verifier guarantees valid pointer */
6256 	*mtu_len = mtu;
6257 
6258 	return ret;
6259 }
6260 
BPF_CALL_5(bpf_xdp_check_mtu,struct xdp_buff *,xdp,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6261 BPF_CALL_5(bpf_xdp_check_mtu, struct xdp_buff *, xdp,
6262 	   u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6263 {
6264 	struct net_device *dev = xdp->rxq->dev;
6265 	int xdp_len = xdp->data_end - xdp->data;
6266 	int ret = BPF_MTU_CHK_RET_SUCCESS;
6267 	int mtu, dev_len;
6268 
6269 	/* XDP variant doesn't support multi-buffer segment check (yet) */
6270 	if (unlikely(flags))
6271 		return -EINVAL;
6272 
6273 	dev = __dev_via_ifindex(dev, ifindex);
6274 	if (unlikely(!dev))
6275 		return -ENODEV;
6276 
6277 	mtu = READ_ONCE(dev->mtu);
6278 
6279 	/* Add L2-header as dev MTU is L3 size */
6280 	dev_len = mtu + dev->hard_header_len;
6281 
6282 	/* Use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6283 	if (*mtu_len)
6284 		xdp_len = *mtu_len + dev->hard_header_len;
6285 
6286 	xdp_len += len_diff; /* minus result pass check */
6287 	if (xdp_len > dev_len)
6288 		ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6289 
6290 	/* BPF verifier guarantees valid pointer */
6291 	*mtu_len = mtu;
6292 
6293 	return ret;
6294 }
6295 
6296 static const struct bpf_func_proto bpf_skb_check_mtu_proto = {
6297 	.func		= bpf_skb_check_mtu,
6298 	.gpl_only	= true,
6299 	.ret_type	= RET_INTEGER,
6300 	.arg1_type      = ARG_PTR_TO_CTX,
6301 	.arg2_type      = ARG_ANYTHING,
6302 	.arg3_type      = ARG_PTR_TO_INT,
6303 	.arg4_type      = ARG_ANYTHING,
6304 	.arg5_type      = ARG_ANYTHING,
6305 };
6306 
6307 static const struct bpf_func_proto bpf_xdp_check_mtu_proto = {
6308 	.func		= bpf_xdp_check_mtu,
6309 	.gpl_only	= true,
6310 	.ret_type	= RET_INTEGER,
6311 	.arg1_type      = ARG_PTR_TO_CTX,
6312 	.arg2_type      = ARG_ANYTHING,
6313 	.arg3_type      = ARG_PTR_TO_INT,
6314 	.arg4_type      = ARG_ANYTHING,
6315 	.arg5_type      = ARG_ANYTHING,
6316 };
6317 
6318 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
bpf_push_seg6_encap(struct sk_buff * skb,u32 type,void * hdr,u32 len)6319 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
6320 {
6321 	int err;
6322 	struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
6323 
6324 	if (!seg6_validate_srh(srh, len, false))
6325 		return -EINVAL;
6326 
6327 	switch (type) {
6328 	case BPF_LWT_ENCAP_SEG6_INLINE:
6329 		if (skb->protocol != htons(ETH_P_IPV6))
6330 			return -EBADMSG;
6331 
6332 		err = seg6_do_srh_inline(skb, srh);
6333 		break;
6334 	case BPF_LWT_ENCAP_SEG6:
6335 		skb_reset_inner_headers(skb);
6336 		skb->encapsulation = 1;
6337 		err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
6338 		break;
6339 	default:
6340 		return -EINVAL;
6341 	}
6342 
6343 	bpf_compute_data_pointers(skb);
6344 	if (err)
6345 		return err;
6346 
6347 	skb_set_transport_header(skb, sizeof(struct ipv6hdr));
6348 
6349 	return seg6_lookup_nexthop(skb, NULL, 0);
6350 }
6351 #endif /* CONFIG_IPV6_SEG6_BPF */
6352 
6353 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
bpf_push_ip_encap(struct sk_buff * skb,void * hdr,u32 len,bool ingress)6354 static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
6355 			     bool ingress)
6356 {
6357 	return bpf_lwt_push_ip_encap(skb, hdr, len, ingress);
6358 }
6359 #endif
6360 
BPF_CALL_4(bpf_lwt_in_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6361 BPF_CALL_4(bpf_lwt_in_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
6362 	   u32, len)
6363 {
6364 	switch (type) {
6365 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
6366 	case BPF_LWT_ENCAP_SEG6:
6367 	case BPF_LWT_ENCAP_SEG6_INLINE:
6368 		return bpf_push_seg6_encap(skb, type, hdr, len);
6369 #endif
6370 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6371 	case BPF_LWT_ENCAP_IP:
6372 		return bpf_push_ip_encap(skb, hdr, len, true /* ingress */);
6373 #endif
6374 	default:
6375 		return -EINVAL;
6376 	}
6377 }
6378 
BPF_CALL_4(bpf_lwt_xmit_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6379 BPF_CALL_4(bpf_lwt_xmit_push_encap, struct sk_buff *, skb, u32, type,
6380 	   void *, hdr, u32, len)
6381 {
6382 	switch (type) {
6383 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6384 	case BPF_LWT_ENCAP_IP:
6385 		return bpf_push_ip_encap(skb, hdr, len, false /* egress */);
6386 #endif
6387 	default:
6388 		return -EINVAL;
6389 	}
6390 }
6391 
6392 static const struct bpf_func_proto bpf_lwt_in_push_encap_proto = {
6393 	.func		= bpf_lwt_in_push_encap,
6394 	.gpl_only	= false,
6395 	.ret_type	= RET_INTEGER,
6396 	.arg1_type	= ARG_PTR_TO_CTX,
6397 	.arg2_type	= ARG_ANYTHING,
6398 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6399 	.arg4_type	= ARG_CONST_SIZE
6400 };
6401 
6402 static const struct bpf_func_proto bpf_lwt_xmit_push_encap_proto = {
6403 	.func		= bpf_lwt_xmit_push_encap,
6404 	.gpl_only	= false,
6405 	.ret_type	= RET_INTEGER,
6406 	.arg1_type	= ARG_PTR_TO_CTX,
6407 	.arg2_type	= ARG_ANYTHING,
6408 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6409 	.arg4_type	= ARG_CONST_SIZE
6410 };
6411 
6412 #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)6413 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
6414 	   const void *, from, u32, len)
6415 {
6416 	struct seg6_bpf_srh_state *srh_state =
6417 		this_cpu_ptr(&seg6_bpf_srh_states);
6418 	struct ipv6_sr_hdr *srh = srh_state->srh;
6419 	void *srh_tlvs, *srh_end, *ptr;
6420 	int srhoff = 0;
6421 
6422 	if (srh == NULL)
6423 		return -EINVAL;
6424 
6425 	srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
6426 	srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
6427 
6428 	ptr = skb->data + offset;
6429 	if (ptr >= srh_tlvs && ptr + len <= srh_end)
6430 		srh_state->valid = false;
6431 	else if (ptr < (void *)&srh->flags ||
6432 		 ptr + len > (void *)&srh->segments)
6433 		return -EFAULT;
6434 
6435 	if (unlikely(bpf_try_make_writable(skb, offset + len)))
6436 		return -EFAULT;
6437 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6438 		return -EINVAL;
6439 	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6440 
6441 	memcpy(skb->data + offset, from, len);
6442 	return 0;
6443 }
6444 
6445 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
6446 	.func		= bpf_lwt_seg6_store_bytes,
6447 	.gpl_only	= false,
6448 	.ret_type	= RET_INTEGER,
6449 	.arg1_type	= ARG_PTR_TO_CTX,
6450 	.arg2_type	= ARG_ANYTHING,
6451 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6452 	.arg4_type	= ARG_CONST_SIZE
6453 };
6454 
bpf_update_srh_state(struct sk_buff * skb)6455 static void bpf_update_srh_state(struct sk_buff *skb)
6456 {
6457 	struct seg6_bpf_srh_state *srh_state =
6458 		this_cpu_ptr(&seg6_bpf_srh_states);
6459 	int srhoff = 0;
6460 
6461 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
6462 		srh_state->srh = NULL;
6463 	} else {
6464 		srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6465 		srh_state->hdrlen = srh_state->srh->hdrlen << 3;
6466 		srh_state->valid = true;
6467 	}
6468 }
6469 
BPF_CALL_4(bpf_lwt_seg6_action,struct sk_buff *,skb,u32,action,void *,param,u32,param_len)6470 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
6471 	   u32, action, void *, param, u32, param_len)
6472 {
6473 	struct seg6_bpf_srh_state *srh_state =
6474 		this_cpu_ptr(&seg6_bpf_srh_states);
6475 	int hdroff = 0;
6476 	int err;
6477 
6478 	switch (action) {
6479 	case SEG6_LOCAL_ACTION_END_X:
6480 		if (!seg6_bpf_has_valid_srh(skb))
6481 			return -EBADMSG;
6482 		if (param_len != sizeof(struct in6_addr))
6483 			return -EINVAL;
6484 		return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
6485 	case SEG6_LOCAL_ACTION_END_T:
6486 		if (!seg6_bpf_has_valid_srh(skb))
6487 			return -EBADMSG;
6488 		if (param_len != sizeof(int))
6489 			return -EINVAL;
6490 		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6491 	case SEG6_LOCAL_ACTION_END_DT6:
6492 		if (!seg6_bpf_has_valid_srh(skb))
6493 			return -EBADMSG;
6494 		if (param_len != sizeof(int))
6495 			return -EINVAL;
6496 
6497 		if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
6498 			return -EBADMSG;
6499 		if (!pskb_pull(skb, hdroff))
6500 			return -EBADMSG;
6501 
6502 		skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
6503 		skb_reset_network_header(skb);
6504 		skb_reset_transport_header(skb);
6505 		skb->encapsulation = 0;
6506 
6507 		bpf_compute_data_pointers(skb);
6508 		bpf_update_srh_state(skb);
6509 		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6510 	case SEG6_LOCAL_ACTION_END_B6:
6511 		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6512 			return -EBADMSG;
6513 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
6514 					  param, param_len);
6515 		if (!err)
6516 			bpf_update_srh_state(skb);
6517 
6518 		return err;
6519 	case SEG6_LOCAL_ACTION_END_B6_ENCAP:
6520 		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6521 			return -EBADMSG;
6522 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
6523 					  param, param_len);
6524 		if (!err)
6525 			bpf_update_srh_state(skb);
6526 
6527 		return err;
6528 	default:
6529 		return -EINVAL;
6530 	}
6531 }
6532 
6533 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
6534 	.func		= bpf_lwt_seg6_action,
6535 	.gpl_only	= false,
6536 	.ret_type	= RET_INTEGER,
6537 	.arg1_type	= ARG_PTR_TO_CTX,
6538 	.arg2_type	= ARG_ANYTHING,
6539 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6540 	.arg4_type	= ARG_CONST_SIZE
6541 };
6542 
BPF_CALL_3(bpf_lwt_seg6_adjust_srh,struct sk_buff *,skb,u32,offset,s32,len)6543 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
6544 	   s32, len)
6545 {
6546 	struct seg6_bpf_srh_state *srh_state =
6547 		this_cpu_ptr(&seg6_bpf_srh_states);
6548 	struct ipv6_sr_hdr *srh = srh_state->srh;
6549 	void *srh_end, *srh_tlvs, *ptr;
6550 	struct ipv6hdr *hdr;
6551 	int srhoff = 0;
6552 	int ret;
6553 
6554 	if (unlikely(srh == NULL))
6555 		return -EINVAL;
6556 
6557 	srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
6558 			((srh->first_segment + 1) << 4));
6559 	srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
6560 			srh_state->hdrlen);
6561 	ptr = skb->data + offset;
6562 
6563 	if (unlikely(ptr < srh_tlvs || ptr > srh_end))
6564 		return -EFAULT;
6565 	if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
6566 		return -EFAULT;
6567 
6568 	if (len > 0) {
6569 		ret = skb_cow_head(skb, len);
6570 		if (unlikely(ret < 0))
6571 			return ret;
6572 
6573 		ret = bpf_skb_net_hdr_push(skb, offset, len);
6574 	} else {
6575 		ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
6576 	}
6577 
6578 	bpf_compute_data_pointers(skb);
6579 	if (unlikely(ret < 0))
6580 		return ret;
6581 
6582 	hdr = (struct ipv6hdr *)skb->data;
6583 	hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
6584 
6585 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6586 		return -EINVAL;
6587 	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6588 	srh_state->hdrlen += len;
6589 	srh_state->valid = false;
6590 	return 0;
6591 }
6592 
6593 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
6594 	.func		= bpf_lwt_seg6_adjust_srh,
6595 	.gpl_only	= false,
6596 	.ret_type	= RET_INTEGER,
6597 	.arg1_type	= ARG_PTR_TO_CTX,
6598 	.arg2_type	= ARG_ANYTHING,
6599 	.arg3_type	= ARG_ANYTHING,
6600 };
6601 #endif /* CONFIG_IPV6_SEG6_BPF */
6602 
6603 #ifdef CONFIG_INET
sk_lookup(struct net * net,struct bpf_sock_tuple * tuple,int dif,int sdif,u8 family,u8 proto)6604 static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
6605 			      int dif, int sdif, u8 family, u8 proto)
6606 {
6607 	struct inet_hashinfo *hinfo = net->ipv4.tcp_death_row.hashinfo;
6608 	bool refcounted = false;
6609 	struct sock *sk = NULL;
6610 
6611 	if (family == AF_INET) {
6612 		__be32 src4 = tuple->ipv4.saddr;
6613 		__be32 dst4 = tuple->ipv4.daddr;
6614 
6615 		if (proto == IPPROTO_TCP)
6616 			sk = __inet_lookup(net, hinfo, NULL, 0,
6617 					   src4, tuple->ipv4.sport,
6618 					   dst4, tuple->ipv4.dport,
6619 					   dif, sdif, &refcounted);
6620 		else
6621 			sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
6622 					       dst4, tuple->ipv4.dport,
6623 					       dif, sdif, net->ipv4.udp_table, NULL);
6624 #if IS_ENABLED(CONFIG_IPV6)
6625 	} else {
6626 		struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
6627 		struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;
6628 
6629 		if (proto == IPPROTO_TCP)
6630 			sk = __inet6_lookup(net, hinfo, NULL, 0,
6631 					    src6, tuple->ipv6.sport,
6632 					    dst6, ntohs(tuple->ipv6.dport),
6633 					    dif, sdif, &refcounted);
6634 		else if (likely(ipv6_bpf_stub))
6635 			sk = ipv6_bpf_stub->udp6_lib_lookup(net,
6636 							    src6, tuple->ipv6.sport,
6637 							    dst6, tuple->ipv6.dport,
6638 							    dif, sdif,
6639 							    net->ipv4.udp_table, NULL);
6640 #endif
6641 	}
6642 
6643 	if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
6644 		WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6645 		sk = NULL;
6646 	}
6647 	return sk;
6648 }
6649 
6650 /* bpf_skc_lookup performs the core lookup for different types of sockets,
6651  * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
6652  */
6653 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)6654 __bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6655 		 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6656 		 u64 flags, int sdif)
6657 {
6658 	struct sock *sk = NULL;
6659 	struct net *net;
6660 	u8 family;
6661 
6662 	if (len == sizeof(tuple->ipv4))
6663 		family = AF_INET;
6664 	else if (len == sizeof(tuple->ipv6))
6665 		family = AF_INET6;
6666 	else
6667 		return NULL;
6668 
6669 	if (unlikely(flags || !((s32)netns_id < 0 || netns_id <= S32_MAX)))
6670 		goto out;
6671 
6672 	if (sdif < 0) {
6673 		if (family == AF_INET)
6674 			sdif = inet_sdif(skb);
6675 		else
6676 			sdif = inet6_sdif(skb);
6677 	}
6678 
6679 	if ((s32)netns_id < 0) {
6680 		net = caller_net;
6681 		sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6682 	} else {
6683 		net = get_net_ns_by_id(caller_net, netns_id);
6684 		if (unlikely(!net))
6685 			goto out;
6686 		sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6687 		put_net(net);
6688 	}
6689 
6690 out:
6691 	return sk;
6692 }
6693 
6694 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)6695 __bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6696 		struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6697 		u64 flags, int sdif)
6698 {
6699 	struct sock *sk = __bpf_skc_lookup(skb, tuple, len, caller_net,
6700 					   ifindex, proto, netns_id, flags,
6701 					   sdif);
6702 
6703 	if (sk) {
6704 		struct sock *sk2 = sk_to_full_sk(sk);
6705 
6706 		/* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6707 		 * sock refcnt is decremented to prevent a request_sock leak.
6708 		 */
6709 		if (!sk_fullsock(sk2))
6710 			sk2 = NULL;
6711 		if (sk2 != sk) {
6712 			sock_gen_put(sk);
6713 			/* Ensure there is no need to bump sk2 refcnt */
6714 			if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6715 				WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6716 				return NULL;
6717 			}
6718 			sk = sk2;
6719 		}
6720 	}
6721 
6722 	return sk;
6723 }
6724 
6725 static struct sock *
bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6726 bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6727 	       u8 proto, u64 netns_id, u64 flags)
6728 {
6729 	struct net *caller_net;
6730 	int ifindex;
6731 
6732 	if (skb->dev) {
6733 		caller_net = dev_net(skb->dev);
6734 		ifindex = skb->dev->ifindex;
6735 	} else {
6736 		caller_net = sock_net(skb->sk);
6737 		ifindex = 0;
6738 	}
6739 
6740 	return __bpf_skc_lookup(skb, tuple, len, caller_net, ifindex, proto,
6741 				netns_id, flags, -1);
6742 }
6743 
6744 static struct sock *
bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6745 bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6746 	      u8 proto, u64 netns_id, u64 flags)
6747 {
6748 	struct sock *sk = bpf_skc_lookup(skb, tuple, len, proto, netns_id,
6749 					 flags);
6750 
6751 	if (sk) {
6752 		struct sock *sk2 = sk_to_full_sk(sk);
6753 
6754 		/* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6755 		 * sock refcnt is decremented to prevent a request_sock leak.
6756 		 */
6757 		if (!sk_fullsock(sk2))
6758 			sk2 = NULL;
6759 		if (sk2 != sk) {
6760 			sock_gen_put(sk);
6761 			/* Ensure there is no need to bump sk2 refcnt */
6762 			if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6763 				WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6764 				return NULL;
6765 			}
6766 			sk = sk2;
6767 		}
6768 	}
6769 
6770 	return sk;
6771 }
6772 
BPF_CALL_5(bpf_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6773 BPF_CALL_5(bpf_skc_lookup_tcp, struct sk_buff *, skb,
6774 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6775 {
6776 	return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
6777 					     netns_id, flags);
6778 }
6779 
6780 static const struct bpf_func_proto bpf_skc_lookup_tcp_proto = {
6781 	.func		= bpf_skc_lookup_tcp,
6782 	.gpl_only	= false,
6783 	.pkt_access	= true,
6784 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
6785 	.arg1_type	= ARG_PTR_TO_CTX,
6786 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6787 	.arg3_type	= ARG_CONST_SIZE,
6788 	.arg4_type	= ARG_ANYTHING,
6789 	.arg5_type	= ARG_ANYTHING,
6790 };
6791 
BPF_CALL_5(bpf_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6792 BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
6793 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6794 {
6795 	return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
6796 					    netns_id, flags);
6797 }
6798 
6799 static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
6800 	.func		= bpf_sk_lookup_tcp,
6801 	.gpl_only	= false,
6802 	.pkt_access	= true,
6803 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6804 	.arg1_type	= ARG_PTR_TO_CTX,
6805 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6806 	.arg3_type	= ARG_CONST_SIZE,
6807 	.arg4_type	= ARG_ANYTHING,
6808 	.arg5_type	= ARG_ANYTHING,
6809 };
6810 
BPF_CALL_5(bpf_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6811 BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
6812 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6813 {
6814 	return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
6815 					    netns_id, flags);
6816 }
6817 
6818 static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
6819 	.func		= bpf_sk_lookup_udp,
6820 	.gpl_only	= false,
6821 	.pkt_access	= true,
6822 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6823 	.arg1_type	= ARG_PTR_TO_CTX,
6824 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6825 	.arg3_type	= ARG_CONST_SIZE,
6826 	.arg4_type	= ARG_ANYTHING,
6827 	.arg5_type	= ARG_ANYTHING,
6828 };
6829 
BPF_CALL_5(bpf_tc_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6830 BPF_CALL_5(bpf_tc_skc_lookup_tcp, struct sk_buff *, skb,
6831 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6832 {
6833 	struct net_device *dev = skb->dev;
6834 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6835 	struct net *caller_net = dev_net(dev);
6836 
6837 	return (unsigned long)__bpf_skc_lookup(skb, tuple, len, caller_net,
6838 					       ifindex, IPPROTO_TCP, netns_id,
6839 					       flags, sdif);
6840 }
6841 
6842 static const struct bpf_func_proto bpf_tc_skc_lookup_tcp_proto = {
6843 	.func		= bpf_tc_skc_lookup_tcp,
6844 	.gpl_only	= false,
6845 	.pkt_access	= true,
6846 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
6847 	.arg1_type	= ARG_PTR_TO_CTX,
6848 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6849 	.arg3_type	= ARG_CONST_SIZE,
6850 	.arg4_type	= ARG_ANYTHING,
6851 	.arg5_type	= ARG_ANYTHING,
6852 };
6853 
BPF_CALL_5(bpf_tc_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6854 BPF_CALL_5(bpf_tc_sk_lookup_tcp, struct sk_buff *, skb,
6855 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6856 {
6857 	struct net_device *dev = skb->dev;
6858 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6859 	struct net *caller_net = dev_net(dev);
6860 
6861 	return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
6862 					      ifindex, IPPROTO_TCP, netns_id,
6863 					      flags, sdif);
6864 }
6865 
6866 static const struct bpf_func_proto bpf_tc_sk_lookup_tcp_proto = {
6867 	.func		= bpf_tc_sk_lookup_tcp,
6868 	.gpl_only	= false,
6869 	.pkt_access	= true,
6870 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6871 	.arg1_type	= ARG_PTR_TO_CTX,
6872 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6873 	.arg3_type	= ARG_CONST_SIZE,
6874 	.arg4_type	= ARG_ANYTHING,
6875 	.arg5_type	= ARG_ANYTHING,
6876 };
6877 
BPF_CALL_5(bpf_tc_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6878 BPF_CALL_5(bpf_tc_sk_lookup_udp, struct sk_buff *, skb,
6879 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6880 {
6881 	struct net_device *dev = skb->dev;
6882 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6883 	struct net *caller_net = dev_net(dev);
6884 
6885 	return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
6886 					      ifindex, IPPROTO_UDP, netns_id,
6887 					      flags, sdif);
6888 }
6889 
6890 static const struct bpf_func_proto bpf_tc_sk_lookup_udp_proto = {
6891 	.func		= bpf_tc_sk_lookup_udp,
6892 	.gpl_only	= false,
6893 	.pkt_access	= true,
6894 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6895 	.arg1_type	= ARG_PTR_TO_CTX,
6896 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6897 	.arg3_type	= ARG_CONST_SIZE,
6898 	.arg4_type	= ARG_ANYTHING,
6899 	.arg5_type	= ARG_ANYTHING,
6900 };
6901 
BPF_CALL_1(bpf_sk_release,struct sock *,sk)6902 BPF_CALL_1(bpf_sk_release, struct sock *, sk)
6903 {
6904 	if (sk && sk_is_refcounted(sk))
6905 		sock_gen_put(sk);
6906 	return 0;
6907 }
6908 
6909 static const struct bpf_func_proto bpf_sk_release_proto = {
6910 	.func		= bpf_sk_release,
6911 	.gpl_only	= false,
6912 	.ret_type	= RET_INTEGER,
6913 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON | OBJ_RELEASE,
6914 };
6915 
BPF_CALL_5(bpf_xdp_sk_lookup_udp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6916 BPF_CALL_5(bpf_xdp_sk_lookup_udp, struct xdp_buff *, ctx,
6917 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6918 {
6919 	struct net_device *dev = ctx->rxq->dev;
6920 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6921 	struct net *caller_net = dev_net(dev);
6922 
6923 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6924 					      ifindex, IPPROTO_UDP, netns_id,
6925 					      flags, sdif);
6926 }
6927 
6928 static const struct bpf_func_proto bpf_xdp_sk_lookup_udp_proto = {
6929 	.func           = bpf_xdp_sk_lookup_udp,
6930 	.gpl_only       = false,
6931 	.pkt_access     = true,
6932 	.ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
6933 	.arg1_type      = ARG_PTR_TO_CTX,
6934 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6935 	.arg3_type      = ARG_CONST_SIZE,
6936 	.arg4_type      = ARG_ANYTHING,
6937 	.arg5_type      = ARG_ANYTHING,
6938 };
6939 
BPF_CALL_5(bpf_xdp_skc_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6940 BPF_CALL_5(bpf_xdp_skc_lookup_tcp, struct xdp_buff *, ctx,
6941 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6942 {
6943 	struct net_device *dev = ctx->rxq->dev;
6944 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6945 	struct net *caller_net = dev_net(dev);
6946 
6947 	return (unsigned long)__bpf_skc_lookup(NULL, tuple, len, caller_net,
6948 					       ifindex, IPPROTO_TCP, netns_id,
6949 					       flags, sdif);
6950 }
6951 
6952 static const struct bpf_func_proto bpf_xdp_skc_lookup_tcp_proto = {
6953 	.func           = bpf_xdp_skc_lookup_tcp,
6954 	.gpl_only       = false,
6955 	.pkt_access     = true,
6956 	.ret_type       = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6957 	.arg1_type      = ARG_PTR_TO_CTX,
6958 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6959 	.arg3_type      = ARG_CONST_SIZE,
6960 	.arg4_type      = ARG_ANYTHING,
6961 	.arg5_type      = ARG_ANYTHING,
6962 };
6963 
BPF_CALL_5(bpf_xdp_sk_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6964 BPF_CALL_5(bpf_xdp_sk_lookup_tcp, struct xdp_buff *, ctx,
6965 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6966 {
6967 	struct net_device *dev = ctx->rxq->dev;
6968 	int ifindex = dev->ifindex, sdif = dev_sdif(dev);
6969 	struct net *caller_net = dev_net(dev);
6970 
6971 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6972 					      ifindex, IPPROTO_TCP, netns_id,
6973 					      flags, sdif);
6974 }
6975 
6976 static const struct bpf_func_proto bpf_xdp_sk_lookup_tcp_proto = {
6977 	.func           = bpf_xdp_sk_lookup_tcp,
6978 	.gpl_only       = false,
6979 	.pkt_access     = true,
6980 	.ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
6981 	.arg1_type      = ARG_PTR_TO_CTX,
6982 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6983 	.arg3_type      = ARG_CONST_SIZE,
6984 	.arg4_type      = ARG_ANYTHING,
6985 	.arg5_type      = ARG_ANYTHING,
6986 };
6987 
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)6988 BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
6989 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6990 {
6991 	return (unsigned long)__bpf_skc_lookup(NULL, tuple, len,
6992 					       sock_net(ctx->sk), 0,
6993 					       IPPROTO_TCP, netns_id, flags,
6994 					       -1);
6995 }
6996 
6997 static const struct bpf_func_proto bpf_sock_addr_skc_lookup_tcp_proto = {
6998 	.func		= bpf_sock_addr_skc_lookup_tcp,
6999 	.gpl_only	= false,
7000 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
7001 	.arg1_type	= ARG_PTR_TO_CTX,
7002 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7003 	.arg3_type	= ARG_CONST_SIZE,
7004 	.arg4_type	= ARG_ANYTHING,
7005 	.arg5_type	= ARG_ANYTHING,
7006 };
7007 
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)7008 BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
7009 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
7010 {
7011 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
7012 					      sock_net(ctx->sk), 0, IPPROTO_TCP,
7013 					      netns_id, flags, -1);
7014 }
7015 
7016 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = {
7017 	.func		= bpf_sock_addr_sk_lookup_tcp,
7018 	.gpl_only	= false,
7019 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
7020 	.arg1_type	= ARG_PTR_TO_CTX,
7021 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7022 	.arg3_type	= ARG_CONST_SIZE,
7023 	.arg4_type	= ARG_ANYTHING,
7024 	.arg5_type	= ARG_ANYTHING,
7025 };
7026 
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)7027 BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx,
7028 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
7029 {
7030 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
7031 					      sock_net(ctx->sk), 0, IPPROTO_UDP,
7032 					      netns_id, flags, -1);
7033 }
7034 
7035 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = {
7036 	.func		= bpf_sock_addr_sk_lookup_udp,
7037 	.gpl_only	= false,
7038 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
7039 	.arg1_type	= ARG_PTR_TO_CTX,
7040 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7041 	.arg3_type	= ARG_CONST_SIZE,
7042 	.arg4_type	= ARG_ANYTHING,
7043 	.arg5_type	= ARG_ANYTHING,
7044 };
7045 
bpf_tcp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)7046 bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
7047 				  struct bpf_insn_access_aux *info)
7048 {
7049 	if (off < 0 || off >= offsetofend(struct bpf_tcp_sock,
7050 					  icsk_retransmits))
7051 		return false;
7052 
7053 	if (off % size != 0)
7054 		return false;
7055 
7056 	switch (off) {
7057 	case offsetof(struct bpf_tcp_sock, bytes_received):
7058 	case offsetof(struct bpf_tcp_sock, bytes_acked):
7059 		return size == sizeof(__u64);
7060 	default:
7061 		return size == sizeof(__u32);
7062 	}
7063 }
7064 
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)7065 u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
7066 				    const struct bpf_insn *si,
7067 				    struct bpf_insn *insn_buf,
7068 				    struct bpf_prog *prog, u32 *target_size)
7069 {
7070 	struct bpf_insn *insn = insn_buf;
7071 
7072 #define BPF_TCP_SOCK_GET_COMMON(FIELD)					\
7073 	do {								\
7074 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, FIELD) >	\
7075 			     sizeof_field(struct bpf_tcp_sock, FIELD));	\
7076 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_sock, FIELD),\
7077 				      si->dst_reg, si->src_reg,		\
7078 				      offsetof(struct tcp_sock, FIELD)); \
7079 	} while (0)
7080 
7081 #define BPF_INET_SOCK_GET_COMMON(FIELD)					\
7082 	do {								\
7083 		BUILD_BUG_ON(sizeof_field(struct inet_connection_sock,	\
7084 					  FIELD) >			\
7085 			     sizeof_field(struct bpf_tcp_sock, FIELD));	\
7086 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			\
7087 					struct inet_connection_sock,	\
7088 					FIELD),				\
7089 				      si->dst_reg, si->src_reg,		\
7090 				      offsetof(				\
7091 					struct inet_connection_sock,	\
7092 					FIELD));			\
7093 	} while (0)
7094 
7095 	BTF_TYPE_EMIT(struct bpf_tcp_sock);
7096 
7097 	switch (si->off) {
7098 	case offsetof(struct bpf_tcp_sock, rtt_min):
7099 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
7100 			     sizeof(struct minmax));
7101 		BUILD_BUG_ON(sizeof(struct minmax) <
7102 			     sizeof(struct minmax_sample));
7103 
7104 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
7105 				      offsetof(struct tcp_sock, rtt_min) +
7106 				      offsetof(struct minmax_sample, v));
7107 		break;
7108 	case offsetof(struct bpf_tcp_sock, snd_cwnd):
7109 		BPF_TCP_SOCK_GET_COMMON(snd_cwnd);
7110 		break;
7111 	case offsetof(struct bpf_tcp_sock, srtt_us):
7112 		BPF_TCP_SOCK_GET_COMMON(srtt_us);
7113 		break;
7114 	case offsetof(struct bpf_tcp_sock, snd_ssthresh):
7115 		BPF_TCP_SOCK_GET_COMMON(snd_ssthresh);
7116 		break;
7117 	case offsetof(struct bpf_tcp_sock, rcv_nxt):
7118 		BPF_TCP_SOCK_GET_COMMON(rcv_nxt);
7119 		break;
7120 	case offsetof(struct bpf_tcp_sock, snd_nxt):
7121 		BPF_TCP_SOCK_GET_COMMON(snd_nxt);
7122 		break;
7123 	case offsetof(struct bpf_tcp_sock, snd_una):
7124 		BPF_TCP_SOCK_GET_COMMON(snd_una);
7125 		break;
7126 	case offsetof(struct bpf_tcp_sock, mss_cache):
7127 		BPF_TCP_SOCK_GET_COMMON(mss_cache);
7128 		break;
7129 	case offsetof(struct bpf_tcp_sock, ecn_flags):
7130 		BPF_TCP_SOCK_GET_COMMON(ecn_flags);
7131 		break;
7132 	case offsetof(struct bpf_tcp_sock, rate_delivered):
7133 		BPF_TCP_SOCK_GET_COMMON(rate_delivered);
7134 		break;
7135 	case offsetof(struct bpf_tcp_sock, rate_interval_us):
7136 		BPF_TCP_SOCK_GET_COMMON(rate_interval_us);
7137 		break;
7138 	case offsetof(struct bpf_tcp_sock, packets_out):
7139 		BPF_TCP_SOCK_GET_COMMON(packets_out);
7140 		break;
7141 	case offsetof(struct bpf_tcp_sock, retrans_out):
7142 		BPF_TCP_SOCK_GET_COMMON(retrans_out);
7143 		break;
7144 	case offsetof(struct bpf_tcp_sock, total_retrans):
7145 		BPF_TCP_SOCK_GET_COMMON(total_retrans);
7146 		break;
7147 	case offsetof(struct bpf_tcp_sock, segs_in):
7148 		BPF_TCP_SOCK_GET_COMMON(segs_in);
7149 		break;
7150 	case offsetof(struct bpf_tcp_sock, data_segs_in):
7151 		BPF_TCP_SOCK_GET_COMMON(data_segs_in);
7152 		break;
7153 	case offsetof(struct bpf_tcp_sock, segs_out):
7154 		BPF_TCP_SOCK_GET_COMMON(segs_out);
7155 		break;
7156 	case offsetof(struct bpf_tcp_sock, data_segs_out):
7157 		BPF_TCP_SOCK_GET_COMMON(data_segs_out);
7158 		break;
7159 	case offsetof(struct bpf_tcp_sock, lost_out):
7160 		BPF_TCP_SOCK_GET_COMMON(lost_out);
7161 		break;
7162 	case offsetof(struct bpf_tcp_sock, sacked_out):
7163 		BPF_TCP_SOCK_GET_COMMON(sacked_out);
7164 		break;
7165 	case offsetof(struct bpf_tcp_sock, bytes_received):
7166 		BPF_TCP_SOCK_GET_COMMON(bytes_received);
7167 		break;
7168 	case offsetof(struct bpf_tcp_sock, bytes_acked):
7169 		BPF_TCP_SOCK_GET_COMMON(bytes_acked);
7170 		break;
7171 	case offsetof(struct bpf_tcp_sock, dsack_dups):
7172 		BPF_TCP_SOCK_GET_COMMON(dsack_dups);
7173 		break;
7174 	case offsetof(struct bpf_tcp_sock, delivered):
7175 		BPF_TCP_SOCK_GET_COMMON(delivered);
7176 		break;
7177 	case offsetof(struct bpf_tcp_sock, delivered_ce):
7178 		BPF_TCP_SOCK_GET_COMMON(delivered_ce);
7179 		break;
7180 	case offsetof(struct bpf_tcp_sock, icsk_retransmits):
7181 		BPF_INET_SOCK_GET_COMMON(icsk_retransmits);
7182 		break;
7183 	}
7184 
7185 	return insn - insn_buf;
7186 }
7187 
BPF_CALL_1(bpf_tcp_sock,struct sock *,sk)7188 BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
7189 {
7190 	if (sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
7191 		return (unsigned long)sk;
7192 
7193 	return (unsigned long)NULL;
7194 }
7195 
7196 const struct bpf_func_proto bpf_tcp_sock_proto = {
7197 	.func		= bpf_tcp_sock,
7198 	.gpl_only	= false,
7199 	.ret_type	= RET_PTR_TO_TCP_SOCK_OR_NULL,
7200 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
7201 };
7202 
BPF_CALL_1(bpf_get_listener_sock,struct sock *,sk)7203 BPF_CALL_1(bpf_get_listener_sock, struct sock *, sk)
7204 {
7205 	sk = sk_to_full_sk(sk);
7206 
7207 	if (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_RCU_FREE))
7208 		return (unsigned long)sk;
7209 
7210 	return (unsigned long)NULL;
7211 }
7212 
7213 static const struct bpf_func_proto bpf_get_listener_sock_proto = {
7214 	.func		= bpf_get_listener_sock,
7215 	.gpl_only	= false,
7216 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
7217 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
7218 };
7219 
BPF_CALL_1(bpf_skb_ecn_set_ce,struct sk_buff *,skb)7220 BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb)
7221 {
7222 	unsigned int iphdr_len;
7223 
7224 	switch (skb_protocol(skb, true)) {
7225 	case cpu_to_be16(ETH_P_IP):
7226 		iphdr_len = sizeof(struct iphdr);
7227 		break;
7228 	case cpu_to_be16(ETH_P_IPV6):
7229 		iphdr_len = sizeof(struct ipv6hdr);
7230 		break;
7231 	default:
7232 		return 0;
7233 	}
7234 
7235 	if (skb_headlen(skb) < iphdr_len)
7236 		return 0;
7237 
7238 	if (skb_cloned(skb) && !skb_clone_writable(skb, iphdr_len))
7239 		return 0;
7240 
7241 	return INET_ECN_set_ce(skb);
7242 }
7243 
bpf_xdp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)7244 bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
7245 				  struct bpf_insn_access_aux *info)
7246 {
7247 	if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id))
7248 		return false;
7249 
7250 	if (off % size != 0)
7251 		return false;
7252 
7253 	switch (off) {
7254 	default:
7255 		return size == sizeof(__u32);
7256 	}
7257 }
7258 
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)7259 u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
7260 				    const struct bpf_insn *si,
7261 				    struct bpf_insn *insn_buf,
7262 				    struct bpf_prog *prog, u32 *target_size)
7263 {
7264 	struct bpf_insn *insn = insn_buf;
7265 
7266 #define BPF_XDP_SOCK_GET(FIELD)						\
7267 	do {								\
7268 		BUILD_BUG_ON(sizeof_field(struct xdp_sock, FIELD) >	\
7269 			     sizeof_field(struct bpf_xdp_sock, FIELD));	\
7270 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\
7271 				      si->dst_reg, si->src_reg,		\
7272 				      offsetof(struct xdp_sock, FIELD)); \
7273 	} while (0)
7274 
7275 	switch (si->off) {
7276 	case offsetof(struct bpf_xdp_sock, queue_id):
7277 		BPF_XDP_SOCK_GET(queue_id);
7278 		break;
7279 	}
7280 
7281 	return insn - insn_buf;
7282 }
7283 
7284 static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = {
7285 	.func           = bpf_skb_ecn_set_ce,
7286 	.gpl_only       = false,
7287 	.ret_type       = RET_INTEGER,
7288 	.arg1_type      = ARG_PTR_TO_CTX,
7289 };
7290 
BPF_CALL_5(bpf_tcp_check_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7291 BPF_CALL_5(bpf_tcp_check_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7292 	   struct tcphdr *, th, u32, th_len)
7293 {
7294 #ifdef CONFIG_SYN_COOKIES
7295 	u32 cookie;
7296 	int ret;
7297 
7298 	if (unlikely(!sk || th_len < sizeof(*th)))
7299 		return -EINVAL;
7300 
7301 	/* sk_listener() allows TCP_NEW_SYN_RECV, which makes no sense here. */
7302 	if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7303 		return -EINVAL;
7304 
7305 	if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7306 		return -EINVAL;
7307 
7308 	if (!th->ack || th->rst || th->syn)
7309 		return -ENOENT;
7310 
7311 	if (unlikely(iph_len < sizeof(struct iphdr)))
7312 		return -EINVAL;
7313 
7314 	if (tcp_synq_no_recent_overflow(sk))
7315 		return -ENOENT;
7316 
7317 	cookie = ntohl(th->ack_seq) - 1;
7318 
7319 	/* Both struct iphdr and struct ipv6hdr have the version field at the
7320 	 * same offset so we can cast to the shorter header (struct iphdr).
7321 	 */
7322 	switch (((struct iphdr *)iph)->version) {
7323 	case 4:
7324 		if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7325 			return -EINVAL;
7326 
7327 		ret = __cookie_v4_check((struct iphdr *)iph, th, cookie);
7328 		break;
7329 
7330 #if IS_BUILTIN(CONFIG_IPV6)
7331 	case 6:
7332 		if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7333 			return -EINVAL;
7334 
7335 		if (sk->sk_family != AF_INET6)
7336 			return -EINVAL;
7337 
7338 		ret = __cookie_v6_check((struct ipv6hdr *)iph, th, cookie);
7339 		break;
7340 #endif /* CONFIG_IPV6 */
7341 
7342 	default:
7343 		return -EPROTONOSUPPORT;
7344 	}
7345 
7346 	if (ret > 0)
7347 		return 0;
7348 
7349 	return -ENOENT;
7350 #else
7351 	return -ENOTSUPP;
7352 #endif
7353 }
7354 
7355 static const struct bpf_func_proto bpf_tcp_check_syncookie_proto = {
7356 	.func		= bpf_tcp_check_syncookie,
7357 	.gpl_only	= true,
7358 	.pkt_access	= true,
7359 	.ret_type	= RET_INTEGER,
7360 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7361 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7362 	.arg3_type	= ARG_CONST_SIZE,
7363 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7364 	.arg5_type	= ARG_CONST_SIZE,
7365 };
7366 
BPF_CALL_5(bpf_tcp_gen_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7367 BPF_CALL_5(bpf_tcp_gen_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7368 	   struct tcphdr *, th, u32, th_len)
7369 {
7370 #ifdef CONFIG_SYN_COOKIES
7371 	u32 cookie;
7372 	u16 mss;
7373 
7374 	if (unlikely(!sk || th_len < sizeof(*th) || th_len != th->doff * 4))
7375 		return -EINVAL;
7376 
7377 	if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7378 		return -EINVAL;
7379 
7380 	if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7381 		return -ENOENT;
7382 
7383 	if (!th->syn || th->ack || th->fin || th->rst)
7384 		return -EINVAL;
7385 
7386 	if (unlikely(iph_len < sizeof(struct iphdr)))
7387 		return -EINVAL;
7388 
7389 	/* Both struct iphdr and struct ipv6hdr have the version field at the
7390 	 * same offset so we can cast to the shorter header (struct iphdr).
7391 	 */
7392 	switch (((struct iphdr *)iph)->version) {
7393 	case 4:
7394 		if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7395 			return -EINVAL;
7396 
7397 		mss = tcp_v4_get_syncookie(sk, iph, th, &cookie);
7398 		break;
7399 
7400 #if IS_BUILTIN(CONFIG_IPV6)
7401 	case 6:
7402 		if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7403 			return -EINVAL;
7404 
7405 		if (sk->sk_family != AF_INET6)
7406 			return -EINVAL;
7407 
7408 		mss = tcp_v6_get_syncookie(sk, iph, th, &cookie);
7409 		break;
7410 #endif /* CONFIG_IPV6 */
7411 
7412 	default:
7413 		return -EPROTONOSUPPORT;
7414 	}
7415 	if (mss == 0)
7416 		return -ENOENT;
7417 
7418 	return cookie | ((u64)mss << 32);
7419 #else
7420 	return -EOPNOTSUPP;
7421 #endif /* CONFIG_SYN_COOKIES */
7422 }
7423 
7424 static const struct bpf_func_proto bpf_tcp_gen_syncookie_proto = {
7425 	.func		= bpf_tcp_gen_syncookie,
7426 	.gpl_only	= true, /* __cookie_v*_init_sequence() is GPL */
7427 	.pkt_access	= true,
7428 	.ret_type	= RET_INTEGER,
7429 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7430 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7431 	.arg3_type	= ARG_CONST_SIZE,
7432 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7433 	.arg5_type	= ARG_CONST_SIZE,
7434 };
7435 
BPF_CALL_3(bpf_sk_assign,struct sk_buff *,skb,struct sock *,sk,u64,flags)7436 BPF_CALL_3(bpf_sk_assign, struct sk_buff *, skb, struct sock *, sk, u64, flags)
7437 {
7438 	if (!sk || flags != 0)
7439 		return -EINVAL;
7440 	if (!skb_at_tc_ingress(skb))
7441 		return -EOPNOTSUPP;
7442 	if (unlikely(dev_net(skb->dev) != sock_net(sk)))
7443 		return -ENETUNREACH;
7444 	if (sk_unhashed(sk))
7445 		return -EOPNOTSUPP;
7446 	if (sk_is_refcounted(sk) &&
7447 	    unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
7448 		return -ENOENT;
7449 
7450 	skb_orphan(skb);
7451 	skb->sk = sk;
7452 	skb->destructor = sock_pfree;
7453 
7454 	return 0;
7455 }
7456 
7457 static const struct bpf_func_proto bpf_sk_assign_proto = {
7458 	.func		= bpf_sk_assign,
7459 	.gpl_only	= false,
7460 	.ret_type	= RET_INTEGER,
7461 	.arg1_type      = ARG_PTR_TO_CTX,
7462 	.arg2_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7463 	.arg3_type	= ARG_ANYTHING,
7464 };
7465 
bpf_search_tcp_opt(const u8 * op,const u8 * opend,u8 search_kind,const u8 * magic,u8 magic_len,bool * eol)7466 static const u8 *bpf_search_tcp_opt(const u8 *op, const u8 *opend,
7467 				    u8 search_kind, const u8 *magic,
7468 				    u8 magic_len, bool *eol)
7469 {
7470 	u8 kind, kind_len;
7471 
7472 	*eol = false;
7473 
7474 	while (op < opend) {
7475 		kind = op[0];
7476 
7477 		if (kind == TCPOPT_EOL) {
7478 			*eol = true;
7479 			return ERR_PTR(-ENOMSG);
7480 		} else if (kind == TCPOPT_NOP) {
7481 			op++;
7482 			continue;
7483 		}
7484 
7485 		if (opend - op < 2 || opend - op < op[1] || op[1] < 2)
7486 			/* Something is wrong in the received header.
7487 			 * Follow the TCP stack's tcp_parse_options()
7488 			 * and just bail here.
7489 			 */
7490 			return ERR_PTR(-EFAULT);
7491 
7492 		kind_len = op[1];
7493 		if (search_kind == kind) {
7494 			if (!magic_len)
7495 				return op;
7496 
7497 			if (magic_len > kind_len - 2)
7498 				return ERR_PTR(-ENOMSG);
7499 
7500 			if (!memcmp(&op[2], magic, magic_len))
7501 				return op;
7502 		}
7503 
7504 		op += kind_len;
7505 	}
7506 
7507 	return ERR_PTR(-ENOMSG);
7508 }
7509 
BPF_CALL_4(bpf_sock_ops_load_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,void *,search_res,u32,len,u64,flags)7510 BPF_CALL_4(bpf_sock_ops_load_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7511 	   void *, search_res, u32, len, u64, flags)
7512 {
7513 	bool eol, load_syn = flags & BPF_LOAD_HDR_OPT_TCP_SYN;
7514 	const u8 *op, *opend, *magic, *search = search_res;
7515 	u8 search_kind, search_len, copy_len, magic_len;
7516 	int ret;
7517 
7518 	/* 2 byte is the minimal option len except TCPOPT_NOP and
7519 	 * TCPOPT_EOL which are useless for the bpf prog to learn
7520 	 * and this helper disallow loading them also.
7521 	 */
7522 	if (len < 2 || flags & ~BPF_LOAD_HDR_OPT_TCP_SYN)
7523 		return -EINVAL;
7524 
7525 	search_kind = search[0];
7526 	search_len = search[1];
7527 
7528 	if (search_len > len || search_kind == TCPOPT_NOP ||
7529 	    search_kind == TCPOPT_EOL)
7530 		return -EINVAL;
7531 
7532 	if (search_kind == TCPOPT_EXP || search_kind == 253) {
7533 		/* 16 or 32 bit magic.  +2 for kind and kind length */
7534 		if (search_len != 4 && search_len != 6)
7535 			return -EINVAL;
7536 		magic = &search[2];
7537 		magic_len = search_len - 2;
7538 	} else {
7539 		if (search_len)
7540 			return -EINVAL;
7541 		magic = NULL;
7542 		magic_len = 0;
7543 	}
7544 
7545 	if (load_syn) {
7546 		ret = bpf_sock_ops_get_syn(bpf_sock, TCP_BPF_SYN, &op);
7547 		if (ret < 0)
7548 			return ret;
7549 
7550 		opend = op + ret;
7551 		op += sizeof(struct tcphdr);
7552 	} else {
7553 		if (!bpf_sock->skb ||
7554 		    bpf_sock->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7555 			/* This bpf_sock->op cannot call this helper */
7556 			return -EPERM;
7557 
7558 		opend = bpf_sock->skb_data_end;
7559 		op = bpf_sock->skb->data + sizeof(struct tcphdr);
7560 	}
7561 
7562 	op = bpf_search_tcp_opt(op, opend, search_kind, magic, magic_len,
7563 				&eol);
7564 	if (IS_ERR(op))
7565 		return PTR_ERR(op);
7566 
7567 	copy_len = op[1];
7568 	ret = copy_len;
7569 	if (copy_len > len) {
7570 		ret = -ENOSPC;
7571 		copy_len = len;
7572 	}
7573 
7574 	memcpy(search_res, op, copy_len);
7575 	return ret;
7576 }
7577 
7578 static const struct bpf_func_proto bpf_sock_ops_load_hdr_opt_proto = {
7579 	.func		= bpf_sock_ops_load_hdr_opt,
7580 	.gpl_only	= false,
7581 	.ret_type	= RET_INTEGER,
7582 	.arg1_type	= ARG_PTR_TO_CTX,
7583 	.arg2_type	= ARG_PTR_TO_MEM,
7584 	.arg3_type	= ARG_CONST_SIZE,
7585 	.arg4_type	= ARG_ANYTHING,
7586 };
7587 
BPF_CALL_4(bpf_sock_ops_store_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,const void *,from,u32,len,u64,flags)7588 BPF_CALL_4(bpf_sock_ops_store_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7589 	   const void *, from, u32, len, u64, flags)
7590 {
7591 	u8 new_kind, new_kind_len, magic_len = 0, *opend;
7592 	const u8 *op, *new_op, *magic = NULL;
7593 	struct sk_buff *skb;
7594 	bool eol;
7595 
7596 	if (bpf_sock->op != BPF_SOCK_OPS_WRITE_HDR_OPT_CB)
7597 		return -EPERM;
7598 
7599 	if (len < 2 || flags)
7600 		return -EINVAL;
7601 
7602 	new_op = from;
7603 	new_kind = new_op[0];
7604 	new_kind_len = new_op[1];
7605 
7606 	if (new_kind_len > len || new_kind == TCPOPT_NOP ||
7607 	    new_kind == TCPOPT_EOL)
7608 		return -EINVAL;
7609 
7610 	if (new_kind_len > bpf_sock->remaining_opt_len)
7611 		return -ENOSPC;
7612 
7613 	/* 253 is another experimental kind */
7614 	if (new_kind == TCPOPT_EXP || new_kind == 253)  {
7615 		if (new_kind_len < 4)
7616 			return -EINVAL;
7617 		/* Match for the 2 byte magic also.
7618 		 * RFC 6994: the magic could be 2 or 4 bytes.
7619 		 * Hence, matching by 2 byte only is on the
7620 		 * conservative side but it is the right
7621 		 * thing to do for the 'search-for-duplication'
7622 		 * purpose.
7623 		 */
7624 		magic = &new_op[2];
7625 		magic_len = 2;
7626 	}
7627 
7628 	/* Check for duplication */
7629 	skb = bpf_sock->skb;
7630 	op = skb->data + sizeof(struct tcphdr);
7631 	opend = bpf_sock->skb_data_end;
7632 
7633 	op = bpf_search_tcp_opt(op, opend, new_kind, magic, magic_len,
7634 				&eol);
7635 	if (!IS_ERR(op))
7636 		return -EEXIST;
7637 
7638 	if (PTR_ERR(op) != -ENOMSG)
7639 		return PTR_ERR(op);
7640 
7641 	if (eol)
7642 		/* The option has been ended.  Treat it as no more
7643 		 * header option can be written.
7644 		 */
7645 		return -ENOSPC;
7646 
7647 	/* No duplication found.  Store the header option. */
7648 	memcpy(opend, from, new_kind_len);
7649 
7650 	bpf_sock->remaining_opt_len -= new_kind_len;
7651 	bpf_sock->skb_data_end += new_kind_len;
7652 
7653 	return 0;
7654 }
7655 
7656 static const struct bpf_func_proto bpf_sock_ops_store_hdr_opt_proto = {
7657 	.func		= bpf_sock_ops_store_hdr_opt,
7658 	.gpl_only	= false,
7659 	.ret_type	= RET_INTEGER,
7660 	.arg1_type	= ARG_PTR_TO_CTX,
7661 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7662 	.arg3_type	= ARG_CONST_SIZE,
7663 	.arg4_type	= ARG_ANYTHING,
7664 };
7665 
BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,u32,len,u64,flags)7666 BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7667 	   u32, len, u64, flags)
7668 {
7669 	if (bpf_sock->op != BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7670 		return -EPERM;
7671 
7672 	if (flags || len < 2)
7673 		return -EINVAL;
7674 
7675 	if (len > bpf_sock->remaining_opt_len)
7676 		return -ENOSPC;
7677 
7678 	bpf_sock->remaining_opt_len -= len;
7679 
7680 	return 0;
7681 }
7682 
7683 static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = {
7684 	.func		= bpf_sock_ops_reserve_hdr_opt,
7685 	.gpl_only	= false,
7686 	.ret_type	= RET_INTEGER,
7687 	.arg1_type	= ARG_PTR_TO_CTX,
7688 	.arg2_type	= ARG_ANYTHING,
7689 	.arg3_type	= ARG_ANYTHING,
7690 };
7691 
BPF_CALL_3(bpf_skb_set_tstamp,struct sk_buff *,skb,u64,tstamp,u32,tstamp_type)7692 BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb,
7693 	   u64, tstamp, u32, tstamp_type)
7694 {
7695 	/* skb_clear_delivery_time() is done for inet protocol */
7696 	if (skb->protocol != htons(ETH_P_IP) &&
7697 	    skb->protocol != htons(ETH_P_IPV6))
7698 		return -EOPNOTSUPP;
7699 
7700 	switch (tstamp_type) {
7701 	case BPF_SKB_TSTAMP_DELIVERY_MONO:
7702 		if (!tstamp)
7703 			return -EINVAL;
7704 		skb->tstamp = tstamp;
7705 		skb->mono_delivery_time = 1;
7706 		break;
7707 	case BPF_SKB_TSTAMP_UNSPEC:
7708 		if (tstamp)
7709 			return -EINVAL;
7710 		skb->tstamp = 0;
7711 		skb->mono_delivery_time = 0;
7712 		break;
7713 	default:
7714 		return -EINVAL;
7715 	}
7716 
7717 	return 0;
7718 }
7719 
7720 static const struct bpf_func_proto bpf_skb_set_tstamp_proto = {
7721 	.func           = bpf_skb_set_tstamp,
7722 	.gpl_only       = false,
7723 	.ret_type       = RET_INTEGER,
7724 	.arg1_type      = ARG_PTR_TO_CTX,
7725 	.arg2_type      = ARG_ANYTHING,
7726 	.arg3_type      = ARG_ANYTHING,
7727 };
7728 
7729 #ifdef CONFIG_SYN_COOKIES
BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv4,struct iphdr *,iph,struct tcphdr *,th,u32,th_len)7730 BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv4, struct iphdr *, iph,
7731 	   struct tcphdr *, th, u32, th_len)
7732 {
7733 	u32 cookie;
7734 	u16 mss;
7735 
7736 	if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
7737 		return -EINVAL;
7738 
7739 	mss = tcp_parse_mss_option(th, 0) ?: TCP_MSS_DEFAULT;
7740 	cookie = __cookie_v4_init_sequence(iph, th, &mss);
7741 
7742 	return cookie | ((u64)mss << 32);
7743 }
7744 
7745 static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv4_proto = {
7746 	.func		= bpf_tcp_raw_gen_syncookie_ipv4,
7747 	.gpl_only	= true, /* __cookie_v4_init_sequence() is GPL */
7748 	.pkt_access	= true,
7749 	.ret_type	= RET_INTEGER,
7750 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7751 	.arg1_size	= sizeof(struct iphdr),
7752 	.arg2_type	= ARG_PTR_TO_MEM,
7753 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
7754 };
7755 
BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv6,struct ipv6hdr *,iph,struct tcphdr *,th,u32,th_len)7756 BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv6, struct ipv6hdr *, iph,
7757 	   struct tcphdr *, th, u32, th_len)
7758 {
7759 #if IS_BUILTIN(CONFIG_IPV6)
7760 	const u16 mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) -
7761 		sizeof(struct ipv6hdr);
7762 	u32 cookie;
7763 	u16 mss;
7764 
7765 	if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
7766 		return -EINVAL;
7767 
7768 	mss = tcp_parse_mss_option(th, 0) ?: mss_clamp;
7769 	cookie = __cookie_v6_init_sequence(iph, th, &mss);
7770 
7771 	return cookie | ((u64)mss << 32);
7772 #else
7773 	return -EPROTONOSUPPORT;
7774 #endif
7775 }
7776 
7777 static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv6_proto = {
7778 	.func		= bpf_tcp_raw_gen_syncookie_ipv6,
7779 	.gpl_only	= true, /* __cookie_v6_init_sequence() is GPL */
7780 	.pkt_access	= true,
7781 	.ret_type	= RET_INTEGER,
7782 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7783 	.arg1_size	= sizeof(struct ipv6hdr),
7784 	.arg2_type	= ARG_PTR_TO_MEM,
7785 	.arg3_type	= ARG_CONST_SIZE_OR_ZERO,
7786 };
7787 
BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv4,struct iphdr *,iph,struct tcphdr *,th)7788 BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv4, struct iphdr *, iph,
7789 	   struct tcphdr *, th)
7790 {
7791 	u32 cookie = ntohl(th->ack_seq) - 1;
7792 
7793 	if (__cookie_v4_check(iph, th, cookie) > 0)
7794 		return 0;
7795 
7796 	return -EACCES;
7797 }
7798 
7799 static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv4_proto = {
7800 	.func		= bpf_tcp_raw_check_syncookie_ipv4,
7801 	.gpl_only	= true, /* __cookie_v4_check is GPL */
7802 	.pkt_access	= true,
7803 	.ret_type	= RET_INTEGER,
7804 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7805 	.arg1_size	= sizeof(struct iphdr),
7806 	.arg2_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7807 	.arg2_size	= sizeof(struct tcphdr),
7808 };
7809 
BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv6,struct ipv6hdr *,iph,struct tcphdr *,th)7810 BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv6, struct ipv6hdr *, iph,
7811 	   struct tcphdr *, th)
7812 {
7813 #if IS_BUILTIN(CONFIG_IPV6)
7814 	u32 cookie = ntohl(th->ack_seq) - 1;
7815 
7816 	if (__cookie_v6_check(iph, th, cookie) > 0)
7817 		return 0;
7818 
7819 	return -EACCES;
7820 #else
7821 	return -EPROTONOSUPPORT;
7822 #endif
7823 }
7824 
7825 static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv6_proto = {
7826 	.func		= bpf_tcp_raw_check_syncookie_ipv6,
7827 	.gpl_only	= true, /* __cookie_v6_check is GPL */
7828 	.pkt_access	= true,
7829 	.ret_type	= RET_INTEGER,
7830 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7831 	.arg1_size	= sizeof(struct ipv6hdr),
7832 	.arg2_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7833 	.arg2_size	= sizeof(struct tcphdr),
7834 };
7835 #endif /* CONFIG_SYN_COOKIES */
7836 
7837 #endif /* CONFIG_INET */
7838 
bpf_helper_changes_pkt_data(void * func)7839 bool bpf_helper_changes_pkt_data(void *func)
7840 {
7841 	if (func == bpf_skb_vlan_push ||
7842 	    func == bpf_skb_vlan_pop ||
7843 	    func == bpf_skb_store_bytes ||
7844 	    func == bpf_skb_change_proto ||
7845 	    func == bpf_skb_change_head ||
7846 	    func == sk_skb_change_head ||
7847 	    func == bpf_skb_change_tail ||
7848 	    func == sk_skb_change_tail ||
7849 	    func == bpf_skb_adjust_room ||
7850 	    func == sk_skb_adjust_room ||
7851 	    func == bpf_skb_pull_data ||
7852 	    func == sk_skb_pull_data ||
7853 	    func == bpf_clone_redirect ||
7854 	    func == bpf_l3_csum_replace ||
7855 	    func == bpf_l4_csum_replace ||
7856 	    func == bpf_xdp_adjust_head ||
7857 	    func == bpf_xdp_adjust_meta ||
7858 	    func == bpf_msg_pull_data ||
7859 	    func == bpf_msg_push_data ||
7860 	    func == bpf_msg_pop_data ||
7861 	    func == bpf_xdp_adjust_tail ||
7862 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
7863 	    func == bpf_lwt_seg6_store_bytes ||
7864 	    func == bpf_lwt_seg6_adjust_srh ||
7865 	    func == bpf_lwt_seg6_action ||
7866 #endif
7867 #ifdef CONFIG_INET
7868 	    func == bpf_sock_ops_store_hdr_opt ||
7869 #endif
7870 	    func == bpf_lwt_in_push_encap ||
7871 	    func == bpf_lwt_xmit_push_encap)
7872 		return true;
7873 
7874 	return false;
7875 }
7876 
7877 const struct bpf_func_proto bpf_event_output_data_proto __weak;
7878 const struct bpf_func_proto bpf_sk_storage_get_cg_sock_proto __weak;
7879 
7880 static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7881 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7882 {
7883 	const struct bpf_func_proto *func_proto;
7884 
7885 	func_proto = cgroup_common_func_proto(func_id, prog);
7886 	if (func_proto)
7887 		return func_proto;
7888 
7889 	func_proto = cgroup_current_func_proto(func_id, prog);
7890 	if (func_proto)
7891 		return func_proto;
7892 
7893 	switch (func_id) {
7894 	case BPF_FUNC_get_socket_cookie:
7895 		return &bpf_get_socket_cookie_sock_proto;
7896 	case BPF_FUNC_get_netns_cookie:
7897 		return &bpf_get_netns_cookie_sock_proto;
7898 	case BPF_FUNC_perf_event_output:
7899 		return &bpf_event_output_data_proto;
7900 	case BPF_FUNC_sk_storage_get:
7901 		return &bpf_sk_storage_get_cg_sock_proto;
7902 	case BPF_FUNC_ktime_get_coarse_ns:
7903 		return &bpf_ktime_get_coarse_ns_proto;
7904 	default:
7905 		return bpf_base_func_proto(func_id);
7906 	}
7907 }
7908 
7909 static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7910 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7911 {
7912 	const struct bpf_func_proto *func_proto;
7913 
7914 	func_proto = cgroup_common_func_proto(func_id, prog);
7915 	if (func_proto)
7916 		return func_proto;
7917 
7918 	func_proto = cgroup_current_func_proto(func_id, prog);
7919 	if (func_proto)
7920 		return func_proto;
7921 
7922 	switch (func_id) {
7923 	case BPF_FUNC_bind:
7924 		switch (prog->expected_attach_type) {
7925 		case BPF_CGROUP_INET4_CONNECT:
7926 		case BPF_CGROUP_INET6_CONNECT:
7927 			return &bpf_bind_proto;
7928 		default:
7929 			return NULL;
7930 		}
7931 	case BPF_FUNC_get_socket_cookie:
7932 		return &bpf_get_socket_cookie_sock_addr_proto;
7933 	case BPF_FUNC_get_netns_cookie:
7934 		return &bpf_get_netns_cookie_sock_addr_proto;
7935 	case BPF_FUNC_perf_event_output:
7936 		return &bpf_event_output_data_proto;
7937 #ifdef CONFIG_INET
7938 	case BPF_FUNC_sk_lookup_tcp:
7939 		return &bpf_sock_addr_sk_lookup_tcp_proto;
7940 	case BPF_FUNC_sk_lookup_udp:
7941 		return &bpf_sock_addr_sk_lookup_udp_proto;
7942 	case BPF_FUNC_sk_release:
7943 		return &bpf_sk_release_proto;
7944 	case BPF_FUNC_skc_lookup_tcp:
7945 		return &bpf_sock_addr_skc_lookup_tcp_proto;
7946 #endif /* CONFIG_INET */
7947 	case BPF_FUNC_sk_storage_get:
7948 		return &bpf_sk_storage_get_proto;
7949 	case BPF_FUNC_sk_storage_delete:
7950 		return &bpf_sk_storage_delete_proto;
7951 	case BPF_FUNC_setsockopt:
7952 		switch (prog->expected_attach_type) {
7953 		case BPF_CGROUP_INET4_BIND:
7954 		case BPF_CGROUP_INET6_BIND:
7955 		case BPF_CGROUP_INET4_CONNECT:
7956 		case BPF_CGROUP_INET6_CONNECT:
7957 		case BPF_CGROUP_UDP4_RECVMSG:
7958 		case BPF_CGROUP_UDP6_RECVMSG:
7959 		case BPF_CGROUP_UDP4_SENDMSG:
7960 		case BPF_CGROUP_UDP6_SENDMSG:
7961 		case BPF_CGROUP_INET4_GETPEERNAME:
7962 		case BPF_CGROUP_INET6_GETPEERNAME:
7963 		case BPF_CGROUP_INET4_GETSOCKNAME:
7964 		case BPF_CGROUP_INET6_GETSOCKNAME:
7965 			return &bpf_sock_addr_setsockopt_proto;
7966 		default:
7967 			return NULL;
7968 		}
7969 	case BPF_FUNC_getsockopt:
7970 		switch (prog->expected_attach_type) {
7971 		case BPF_CGROUP_INET4_BIND:
7972 		case BPF_CGROUP_INET6_BIND:
7973 		case BPF_CGROUP_INET4_CONNECT:
7974 		case BPF_CGROUP_INET6_CONNECT:
7975 		case BPF_CGROUP_UDP4_RECVMSG:
7976 		case BPF_CGROUP_UDP6_RECVMSG:
7977 		case BPF_CGROUP_UDP4_SENDMSG:
7978 		case BPF_CGROUP_UDP6_SENDMSG:
7979 		case BPF_CGROUP_INET4_GETPEERNAME:
7980 		case BPF_CGROUP_INET6_GETPEERNAME:
7981 		case BPF_CGROUP_INET4_GETSOCKNAME:
7982 		case BPF_CGROUP_INET6_GETSOCKNAME:
7983 			return &bpf_sock_addr_getsockopt_proto;
7984 		default:
7985 			return NULL;
7986 		}
7987 	default:
7988 		return bpf_sk_base_func_proto(func_id);
7989 	}
7990 }
7991 
7992 static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7993 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7994 {
7995 	switch (func_id) {
7996 	case BPF_FUNC_skb_load_bytes:
7997 		return &bpf_skb_load_bytes_proto;
7998 	case BPF_FUNC_skb_load_bytes_relative:
7999 		return &bpf_skb_load_bytes_relative_proto;
8000 	case BPF_FUNC_get_socket_cookie:
8001 		return &bpf_get_socket_cookie_proto;
8002 	case BPF_FUNC_get_socket_uid:
8003 		return &bpf_get_socket_uid_proto;
8004 	case BPF_FUNC_perf_event_output:
8005 		return &bpf_skb_event_output_proto;
8006 	default:
8007 		return bpf_sk_base_func_proto(func_id);
8008 	}
8009 }
8010 
8011 const struct bpf_func_proto bpf_sk_storage_get_proto __weak;
8012 const struct bpf_func_proto bpf_sk_storage_delete_proto __weak;
8013 
8014 static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8015 cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8016 {
8017 	const struct bpf_func_proto *func_proto;
8018 
8019 	func_proto = cgroup_common_func_proto(func_id, prog);
8020 	if (func_proto)
8021 		return func_proto;
8022 
8023 	switch (func_id) {
8024 	case BPF_FUNC_sk_fullsock:
8025 		return &bpf_sk_fullsock_proto;
8026 	case BPF_FUNC_sk_storage_get:
8027 		return &bpf_sk_storage_get_proto;
8028 	case BPF_FUNC_sk_storage_delete:
8029 		return &bpf_sk_storage_delete_proto;
8030 	case BPF_FUNC_perf_event_output:
8031 		return &bpf_skb_event_output_proto;
8032 #ifdef CONFIG_SOCK_CGROUP_DATA
8033 	case BPF_FUNC_skb_cgroup_id:
8034 		return &bpf_skb_cgroup_id_proto;
8035 	case BPF_FUNC_skb_ancestor_cgroup_id:
8036 		return &bpf_skb_ancestor_cgroup_id_proto;
8037 	case BPF_FUNC_sk_cgroup_id:
8038 		return &bpf_sk_cgroup_id_proto;
8039 	case BPF_FUNC_sk_ancestor_cgroup_id:
8040 		return &bpf_sk_ancestor_cgroup_id_proto;
8041 #endif
8042 #ifdef CONFIG_INET
8043 	case BPF_FUNC_sk_lookup_tcp:
8044 		return &bpf_sk_lookup_tcp_proto;
8045 	case BPF_FUNC_sk_lookup_udp:
8046 		return &bpf_sk_lookup_udp_proto;
8047 	case BPF_FUNC_sk_release:
8048 		return &bpf_sk_release_proto;
8049 	case BPF_FUNC_skc_lookup_tcp:
8050 		return &bpf_skc_lookup_tcp_proto;
8051 	case BPF_FUNC_tcp_sock:
8052 		return &bpf_tcp_sock_proto;
8053 	case BPF_FUNC_get_listener_sock:
8054 		return &bpf_get_listener_sock_proto;
8055 	case BPF_FUNC_skb_ecn_set_ce:
8056 		return &bpf_skb_ecn_set_ce_proto;
8057 #endif
8058 	default:
8059 		return sk_filter_func_proto(func_id, prog);
8060 	}
8061 }
8062 
8063 static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8064 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8065 {
8066 	switch (func_id) {
8067 	case BPF_FUNC_skb_store_bytes:
8068 		return &bpf_skb_store_bytes_proto;
8069 	case BPF_FUNC_skb_load_bytes:
8070 		return &bpf_skb_load_bytes_proto;
8071 	case BPF_FUNC_skb_load_bytes_relative:
8072 		return &bpf_skb_load_bytes_relative_proto;
8073 	case BPF_FUNC_skb_pull_data:
8074 		return &bpf_skb_pull_data_proto;
8075 	case BPF_FUNC_csum_diff:
8076 		return &bpf_csum_diff_proto;
8077 	case BPF_FUNC_csum_update:
8078 		return &bpf_csum_update_proto;
8079 	case BPF_FUNC_csum_level:
8080 		return &bpf_csum_level_proto;
8081 	case BPF_FUNC_l3_csum_replace:
8082 		return &bpf_l3_csum_replace_proto;
8083 	case BPF_FUNC_l4_csum_replace:
8084 		return &bpf_l4_csum_replace_proto;
8085 	case BPF_FUNC_clone_redirect:
8086 		return &bpf_clone_redirect_proto;
8087 	case BPF_FUNC_get_cgroup_classid:
8088 		return &bpf_get_cgroup_classid_proto;
8089 	case BPF_FUNC_skb_vlan_push:
8090 		return &bpf_skb_vlan_push_proto;
8091 	case BPF_FUNC_skb_vlan_pop:
8092 		return &bpf_skb_vlan_pop_proto;
8093 	case BPF_FUNC_skb_change_proto:
8094 		return &bpf_skb_change_proto_proto;
8095 	case BPF_FUNC_skb_change_type:
8096 		return &bpf_skb_change_type_proto;
8097 	case BPF_FUNC_skb_adjust_room:
8098 		return &bpf_skb_adjust_room_proto;
8099 	case BPF_FUNC_skb_change_tail:
8100 		return &bpf_skb_change_tail_proto;
8101 	case BPF_FUNC_skb_change_head:
8102 		return &bpf_skb_change_head_proto;
8103 	case BPF_FUNC_skb_get_tunnel_key:
8104 		return &bpf_skb_get_tunnel_key_proto;
8105 	case BPF_FUNC_skb_set_tunnel_key:
8106 		return bpf_get_skb_set_tunnel_proto(func_id);
8107 	case BPF_FUNC_skb_get_tunnel_opt:
8108 		return &bpf_skb_get_tunnel_opt_proto;
8109 	case BPF_FUNC_skb_set_tunnel_opt:
8110 		return bpf_get_skb_set_tunnel_proto(func_id);
8111 	case BPF_FUNC_redirect:
8112 		return &bpf_redirect_proto;
8113 	case BPF_FUNC_redirect_neigh:
8114 		return &bpf_redirect_neigh_proto;
8115 	case BPF_FUNC_redirect_peer:
8116 		return &bpf_redirect_peer_proto;
8117 	case BPF_FUNC_get_route_realm:
8118 		return &bpf_get_route_realm_proto;
8119 	case BPF_FUNC_get_hash_recalc:
8120 		return &bpf_get_hash_recalc_proto;
8121 	case BPF_FUNC_set_hash_invalid:
8122 		return &bpf_set_hash_invalid_proto;
8123 	case BPF_FUNC_set_hash:
8124 		return &bpf_set_hash_proto;
8125 	case BPF_FUNC_perf_event_output:
8126 		return &bpf_skb_event_output_proto;
8127 	case BPF_FUNC_get_smp_processor_id:
8128 		return &bpf_get_smp_processor_id_proto;
8129 	case BPF_FUNC_skb_under_cgroup:
8130 		return &bpf_skb_under_cgroup_proto;
8131 	case BPF_FUNC_get_socket_cookie:
8132 		return &bpf_get_socket_cookie_proto;
8133 	case BPF_FUNC_get_socket_uid:
8134 		return &bpf_get_socket_uid_proto;
8135 	case BPF_FUNC_fib_lookup:
8136 		return &bpf_skb_fib_lookup_proto;
8137 	case BPF_FUNC_check_mtu:
8138 		return &bpf_skb_check_mtu_proto;
8139 	case BPF_FUNC_sk_fullsock:
8140 		return &bpf_sk_fullsock_proto;
8141 	case BPF_FUNC_sk_storage_get:
8142 		return &bpf_sk_storage_get_proto;
8143 	case BPF_FUNC_sk_storage_delete:
8144 		return &bpf_sk_storage_delete_proto;
8145 #ifdef CONFIG_XFRM
8146 	case BPF_FUNC_skb_get_xfrm_state:
8147 		return &bpf_skb_get_xfrm_state_proto;
8148 #endif
8149 #ifdef CONFIG_CGROUP_NET_CLASSID
8150 	case BPF_FUNC_skb_cgroup_classid:
8151 		return &bpf_skb_cgroup_classid_proto;
8152 #endif
8153 #ifdef CONFIG_SOCK_CGROUP_DATA
8154 	case BPF_FUNC_skb_cgroup_id:
8155 		return &bpf_skb_cgroup_id_proto;
8156 	case BPF_FUNC_skb_ancestor_cgroup_id:
8157 		return &bpf_skb_ancestor_cgroup_id_proto;
8158 #endif
8159 #ifdef CONFIG_INET
8160 	case BPF_FUNC_sk_lookup_tcp:
8161 		return &bpf_tc_sk_lookup_tcp_proto;
8162 	case BPF_FUNC_sk_lookup_udp:
8163 		return &bpf_tc_sk_lookup_udp_proto;
8164 	case BPF_FUNC_sk_release:
8165 		return &bpf_sk_release_proto;
8166 	case BPF_FUNC_tcp_sock:
8167 		return &bpf_tcp_sock_proto;
8168 	case BPF_FUNC_get_listener_sock:
8169 		return &bpf_get_listener_sock_proto;
8170 	case BPF_FUNC_skc_lookup_tcp:
8171 		return &bpf_tc_skc_lookup_tcp_proto;
8172 	case BPF_FUNC_tcp_check_syncookie:
8173 		return &bpf_tcp_check_syncookie_proto;
8174 	case BPF_FUNC_skb_ecn_set_ce:
8175 		return &bpf_skb_ecn_set_ce_proto;
8176 	case BPF_FUNC_tcp_gen_syncookie:
8177 		return &bpf_tcp_gen_syncookie_proto;
8178 	case BPF_FUNC_sk_assign:
8179 		return &bpf_sk_assign_proto;
8180 	case BPF_FUNC_skb_set_tstamp:
8181 		return &bpf_skb_set_tstamp_proto;
8182 #ifdef CONFIG_SYN_COOKIES
8183 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
8184 		return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
8185 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
8186 		return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
8187 	case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
8188 		return &bpf_tcp_raw_check_syncookie_ipv4_proto;
8189 	case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
8190 		return &bpf_tcp_raw_check_syncookie_ipv6_proto;
8191 #endif
8192 #endif
8193 	default:
8194 		return bpf_sk_base_func_proto(func_id);
8195 	}
8196 }
8197 
8198 static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8199 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8200 {
8201 	switch (func_id) {
8202 	case BPF_FUNC_perf_event_output:
8203 		return &bpf_xdp_event_output_proto;
8204 	case BPF_FUNC_get_smp_processor_id:
8205 		return &bpf_get_smp_processor_id_proto;
8206 	case BPF_FUNC_csum_diff:
8207 		return &bpf_csum_diff_proto;
8208 	case BPF_FUNC_xdp_adjust_head:
8209 		return &bpf_xdp_adjust_head_proto;
8210 	case BPF_FUNC_xdp_adjust_meta:
8211 		return &bpf_xdp_adjust_meta_proto;
8212 	case BPF_FUNC_redirect:
8213 		return &bpf_xdp_redirect_proto;
8214 	case BPF_FUNC_redirect_map:
8215 		return &bpf_xdp_redirect_map_proto;
8216 	case BPF_FUNC_xdp_adjust_tail:
8217 		return &bpf_xdp_adjust_tail_proto;
8218 	case BPF_FUNC_xdp_get_buff_len:
8219 		return &bpf_xdp_get_buff_len_proto;
8220 	case BPF_FUNC_xdp_load_bytes:
8221 		return &bpf_xdp_load_bytes_proto;
8222 	case BPF_FUNC_xdp_store_bytes:
8223 		return &bpf_xdp_store_bytes_proto;
8224 	case BPF_FUNC_fib_lookup:
8225 		return &bpf_xdp_fib_lookup_proto;
8226 	case BPF_FUNC_check_mtu:
8227 		return &bpf_xdp_check_mtu_proto;
8228 #ifdef CONFIG_INET
8229 	case BPF_FUNC_sk_lookup_udp:
8230 		return &bpf_xdp_sk_lookup_udp_proto;
8231 	case BPF_FUNC_sk_lookup_tcp:
8232 		return &bpf_xdp_sk_lookup_tcp_proto;
8233 	case BPF_FUNC_sk_release:
8234 		return &bpf_sk_release_proto;
8235 	case BPF_FUNC_skc_lookup_tcp:
8236 		return &bpf_xdp_skc_lookup_tcp_proto;
8237 	case BPF_FUNC_tcp_check_syncookie:
8238 		return &bpf_tcp_check_syncookie_proto;
8239 	case BPF_FUNC_tcp_gen_syncookie:
8240 		return &bpf_tcp_gen_syncookie_proto;
8241 #ifdef CONFIG_SYN_COOKIES
8242 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
8243 		return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
8244 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
8245 		return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
8246 	case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
8247 		return &bpf_tcp_raw_check_syncookie_ipv4_proto;
8248 	case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
8249 		return &bpf_tcp_raw_check_syncookie_ipv6_proto;
8250 #endif
8251 #endif
8252 	default:
8253 		return bpf_sk_base_func_proto(func_id);
8254 	}
8255 
8256 #if IS_MODULE(CONFIG_NF_CONNTRACK) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)
8257 	/* The nf_conn___init type is used in the NF_CONNTRACK kfuncs. The
8258 	 * kfuncs are defined in two different modules, and we want to be able
8259 	 * to use them interchangably with the same BTF type ID. Because modules
8260 	 * can't de-duplicate BTF IDs between each other, we need the type to be
8261 	 * referenced in the vmlinux BTF or the verifier will get confused about
8262 	 * the different types. So we add this dummy type reference which will
8263 	 * be included in vmlinux BTF, allowing both modules to refer to the
8264 	 * same type ID.
8265 	 */
8266 	BTF_TYPE_EMIT(struct nf_conn___init);
8267 #endif
8268 }
8269 
8270 const struct bpf_func_proto bpf_sock_map_update_proto __weak;
8271 const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
8272 
8273 static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8274 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8275 {
8276 	const struct bpf_func_proto *func_proto;
8277 
8278 	func_proto = cgroup_common_func_proto(func_id, prog);
8279 	if (func_proto)
8280 		return func_proto;
8281 
8282 	switch (func_id) {
8283 	case BPF_FUNC_setsockopt:
8284 		return &bpf_sock_ops_setsockopt_proto;
8285 	case BPF_FUNC_getsockopt:
8286 		return &bpf_sock_ops_getsockopt_proto;
8287 	case BPF_FUNC_sock_ops_cb_flags_set:
8288 		return &bpf_sock_ops_cb_flags_set_proto;
8289 	case BPF_FUNC_sock_map_update:
8290 		return &bpf_sock_map_update_proto;
8291 	case BPF_FUNC_sock_hash_update:
8292 		return &bpf_sock_hash_update_proto;
8293 	case BPF_FUNC_get_socket_cookie:
8294 		return &bpf_get_socket_cookie_sock_ops_proto;
8295 	case BPF_FUNC_perf_event_output:
8296 		return &bpf_event_output_data_proto;
8297 	case BPF_FUNC_sk_storage_get:
8298 		return &bpf_sk_storage_get_proto;
8299 	case BPF_FUNC_sk_storage_delete:
8300 		return &bpf_sk_storage_delete_proto;
8301 	case BPF_FUNC_get_netns_cookie:
8302 		return &bpf_get_netns_cookie_sock_ops_proto;
8303 #ifdef CONFIG_INET
8304 	case BPF_FUNC_load_hdr_opt:
8305 		return &bpf_sock_ops_load_hdr_opt_proto;
8306 	case BPF_FUNC_store_hdr_opt:
8307 		return &bpf_sock_ops_store_hdr_opt_proto;
8308 	case BPF_FUNC_reserve_hdr_opt:
8309 		return &bpf_sock_ops_reserve_hdr_opt_proto;
8310 	case BPF_FUNC_tcp_sock:
8311 		return &bpf_tcp_sock_proto;
8312 #endif /* CONFIG_INET */
8313 	default:
8314 		return bpf_sk_base_func_proto(func_id);
8315 	}
8316 }
8317 
8318 const struct bpf_func_proto bpf_msg_redirect_map_proto __weak;
8319 const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak;
8320 
8321 static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8322 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8323 {
8324 	switch (func_id) {
8325 	case BPF_FUNC_msg_redirect_map:
8326 		return &bpf_msg_redirect_map_proto;
8327 	case BPF_FUNC_msg_redirect_hash:
8328 		return &bpf_msg_redirect_hash_proto;
8329 	case BPF_FUNC_msg_apply_bytes:
8330 		return &bpf_msg_apply_bytes_proto;
8331 	case BPF_FUNC_msg_cork_bytes:
8332 		return &bpf_msg_cork_bytes_proto;
8333 	case BPF_FUNC_msg_pull_data:
8334 		return &bpf_msg_pull_data_proto;
8335 	case BPF_FUNC_msg_push_data:
8336 		return &bpf_msg_push_data_proto;
8337 	case BPF_FUNC_msg_pop_data:
8338 		return &bpf_msg_pop_data_proto;
8339 	case BPF_FUNC_perf_event_output:
8340 		return &bpf_event_output_data_proto;
8341 	case BPF_FUNC_get_current_uid_gid:
8342 		return &bpf_get_current_uid_gid_proto;
8343 	case BPF_FUNC_get_current_pid_tgid:
8344 		return &bpf_get_current_pid_tgid_proto;
8345 	case BPF_FUNC_sk_storage_get:
8346 		return &bpf_sk_storage_get_proto;
8347 	case BPF_FUNC_sk_storage_delete:
8348 		return &bpf_sk_storage_delete_proto;
8349 	case BPF_FUNC_get_netns_cookie:
8350 		return &bpf_get_netns_cookie_sk_msg_proto;
8351 #ifdef CONFIG_CGROUP_NET_CLASSID
8352 	case BPF_FUNC_get_cgroup_classid:
8353 		return &bpf_get_cgroup_classid_curr_proto;
8354 #endif
8355 	default:
8356 		return bpf_sk_base_func_proto(func_id);
8357 	}
8358 }
8359 
8360 const struct bpf_func_proto bpf_sk_redirect_map_proto __weak;
8361 const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak;
8362 
8363 static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8364 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8365 {
8366 	switch (func_id) {
8367 	case BPF_FUNC_skb_store_bytes:
8368 		return &bpf_skb_store_bytes_proto;
8369 	case BPF_FUNC_skb_load_bytes:
8370 		return &bpf_skb_load_bytes_proto;
8371 	case BPF_FUNC_skb_pull_data:
8372 		return &sk_skb_pull_data_proto;
8373 	case BPF_FUNC_skb_change_tail:
8374 		return &sk_skb_change_tail_proto;
8375 	case BPF_FUNC_skb_change_head:
8376 		return &sk_skb_change_head_proto;
8377 	case BPF_FUNC_skb_adjust_room:
8378 		return &sk_skb_adjust_room_proto;
8379 	case BPF_FUNC_get_socket_cookie:
8380 		return &bpf_get_socket_cookie_proto;
8381 	case BPF_FUNC_get_socket_uid:
8382 		return &bpf_get_socket_uid_proto;
8383 	case BPF_FUNC_sk_redirect_map:
8384 		return &bpf_sk_redirect_map_proto;
8385 	case BPF_FUNC_sk_redirect_hash:
8386 		return &bpf_sk_redirect_hash_proto;
8387 	case BPF_FUNC_perf_event_output:
8388 		return &bpf_skb_event_output_proto;
8389 #ifdef CONFIG_INET
8390 	case BPF_FUNC_sk_lookup_tcp:
8391 		return &bpf_sk_lookup_tcp_proto;
8392 	case BPF_FUNC_sk_lookup_udp:
8393 		return &bpf_sk_lookup_udp_proto;
8394 	case BPF_FUNC_sk_release:
8395 		return &bpf_sk_release_proto;
8396 	case BPF_FUNC_skc_lookup_tcp:
8397 		return &bpf_skc_lookup_tcp_proto;
8398 #endif
8399 	default:
8400 		return bpf_sk_base_func_proto(func_id);
8401 	}
8402 }
8403 
8404 static const struct bpf_func_proto *
flow_dissector_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8405 flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8406 {
8407 	switch (func_id) {
8408 	case BPF_FUNC_skb_load_bytes:
8409 		return &bpf_flow_dissector_load_bytes_proto;
8410 	default:
8411 		return bpf_sk_base_func_proto(func_id);
8412 	}
8413 }
8414 
8415 static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8416 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8417 {
8418 	switch (func_id) {
8419 	case BPF_FUNC_skb_load_bytes:
8420 		return &bpf_skb_load_bytes_proto;
8421 	case BPF_FUNC_skb_pull_data:
8422 		return &bpf_skb_pull_data_proto;
8423 	case BPF_FUNC_csum_diff:
8424 		return &bpf_csum_diff_proto;
8425 	case BPF_FUNC_get_cgroup_classid:
8426 		return &bpf_get_cgroup_classid_proto;
8427 	case BPF_FUNC_get_route_realm:
8428 		return &bpf_get_route_realm_proto;
8429 	case BPF_FUNC_get_hash_recalc:
8430 		return &bpf_get_hash_recalc_proto;
8431 	case BPF_FUNC_perf_event_output:
8432 		return &bpf_skb_event_output_proto;
8433 	case BPF_FUNC_get_smp_processor_id:
8434 		return &bpf_get_smp_processor_id_proto;
8435 	case BPF_FUNC_skb_under_cgroup:
8436 		return &bpf_skb_under_cgroup_proto;
8437 	default:
8438 		return bpf_sk_base_func_proto(func_id);
8439 	}
8440 }
8441 
8442 static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8443 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8444 {
8445 	switch (func_id) {
8446 	case BPF_FUNC_lwt_push_encap:
8447 		return &bpf_lwt_in_push_encap_proto;
8448 	default:
8449 		return lwt_out_func_proto(func_id, prog);
8450 	}
8451 }
8452 
8453 static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8454 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8455 {
8456 	switch (func_id) {
8457 	case BPF_FUNC_skb_get_tunnel_key:
8458 		return &bpf_skb_get_tunnel_key_proto;
8459 	case BPF_FUNC_skb_set_tunnel_key:
8460 		return bpf_get_skb_set_tunnel_proto(func_id);
8461 	case BPF_FUNC_skb_get_tunnel_opt:
8462 		return &bpf_skb_get_tunnel_opt_proto;
8463 	case BPF_FUNC_skb_set_tunnel_opt:
8464 		return bpf_get_skb_set_tunnel_proto(func_id);
8465 	case BPF_FUNC_redirect:
8466 		return &bpf_redirect_proto;
8467 	case BPF_FUNC_clone_redirect:
8468 		return &bpf_clone_redirect_proto;
8469 	case BPF_FUNC_skb_change_tail:
8470 		return &bpf_skb_change_tail_proto;
8471 	case BPF_FUNC_skb_change_head:
8472 		return &bpf_skb_change_head_proto;
8473 	case BPF_FUNC_skb_store_bytes:
8474 		return &bpf_skb_store_bytes_proto;
8475 	case BPF_FUNC_csum_update:
8476 		return &bpf_csum_update_proto;
8477 	case BPF_FUNC_csum_level:
8478 		return &bpf_csum_level_proto;
8479 	case BPF_FUNC_l3_csum_replace:
8480 		return &bpf_l3_csum_replace_proto;
8481 	case BPF_FUNC_l4_csum_replace:
8482 		return &bpf_l4_csum_replace_proto;
8483 	case BPF_FUNC_set_hash_invalid:
8484 		return &bpf_set_hash_invalid_proto;
8485 	case BPF_FUNC_lwt_push_encap:
8486 		return &bpf_lwt_xmit_push_encap_proto;
8487 	default:
8488 		return lwt_out_func_proto(func_id, prog);
8489 	}
8490 }
8491 
8492 static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8493 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8494 {
8495 	switch (func_id) {
8496 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
8497 	case BPF_FUNC_lwt_seg6_store_bytes:
8498 		return &bpf_lwt_seg6_store_bytes_proto;
8499 	case BPF_FUNC_lwt_seg6_action:
8500 		return &bpf_lwt_seg6_action_proto;
8501 	case BPF_FUNC_lwt_seg6_adjust_srh:
8502 		return &bpf_lwt_seg6_adjust_srh_proto;
8503 #endif
8504 	default:
8505 		return lwt_out_func_proto(func_id, prog);
8506 	}
8507 }
8508 
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)8509 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
8510 				    const struct bpf_prog *prog,
8511 				    struct bpf_insn_access_aux *info)
8512 {
8513 	const int size_default = sizeof(__u32);
8514 
8515 	if (off < 0 || off >= sizeof(struct __sk_buff))
8516 		return false;
8517 
8518 	/* The verifier guarantees that size > 0. */
8519 	if (off % size != 0)
8520 		return false;
8521 
8522 	switch (off) {
8523 	case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8524 		if (off + size > offsetofend(struct __sk_buff, cb[4]))
8525 			return false;
8526 		break;
8527 	case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
8528 	case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
8529 	case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
8530 	case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
8531 	case bpf_ctx_range(struct __sk_buff, data):
8532 	case bpf_ctx_range(struct __sk_buff, data_meta):
8533 	case bpf_ctx_range(struct __sk_buff, data_end):
8534 		if (size != size_default)
8535 			return false;
8536 		break;
8537 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
8538 		return false;
8539 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8540 		if (type == BPF_WRITE || size != sizeof(__u64))
8541 			return false;
8542 		break;
8543 	case bpf_ctx_range(struct __sk_buff, tstamp):
8544 		if (size != sizeof(__u64))
8545 			return false;
8546 		break;
8547 	case offsetof(struct __sk_buff, sk):
8548 		if (type == BPF_WRITE || size != sizeof(__u64))
8549 			return false;
8550 		info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
8551 		break;
8552 	case offsetof(struct __sk_buff, tstamp_type):
8553 		return false;
8554 	case offsetofend(struct __sk_buff, tstamp_type) ... offsetof(struct __sk_buff, hwtstamp) - 1:
8555 		/* Explicitly prohibit access to padding in __sk_buff. */
8556 		return false;
8557 	default:
8558 		/* Only narrow read access allowed for now. */
8559 		if (type == BPF_WRITE) {
8560 			if (size != size_default)
8561 				return false;
8562 		} else {
8563 			bpf_ctx_record_field_size(info, size_default);
8564 			if (!bpf_ctx_narrow_access_ok(off, size, size_default))
8565 				return false;
8566 		}
8567 	}
8568 
8569 	return true;
8570 }
8571 
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)8572 static bool sk_filter_is_valid_access(int off, int size,
8573 				      enum bpf_access_type type,
8574 				      const struct bpf_prog *prog,
8575 				      struct bpf_insn_access_aux *info)
8576 {
8577 	switch (off) {
8578 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8579 	case bpf_ctx_range(struct __sk_buff, data):
8580 	case bpf_ctx_range(struct __sk_buff, data_meta):
8581 	case bpf_ctx_range(struct __sk_buff, data_end):
8582 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8583 	case bpf_ctx_range(struct __sk_buff, tstamp):
8584 	case bpf_ctx_range(struct __sk_buff, wire_len):
8585 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8586 		return false;
8587 	}
8588 
8589 	if (type == BPF_WRITE) {
8590 		switch (off) {
8591 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8592 			break;
8593 		default:
8594 			return false;
8595 		}
8596 	}
8597 
8598 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8599 }
8600 
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)8601 static bool cg_skb_is_valid_access(int off, int size,
8602 				   enum bpf_access_type type,
8603 				   const struct bpf_prog *prog,
8604 				   struct bpf_insn_access_aux *info)
8605 {
8606 	switch (off) {
8607 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8608 	case bpf_ctx_range(struct __sk_buff, data_meta):
8609 	case bpf_ctx_range(struct __sk_buff, wire_len):
8610 		return false;
8611 	case bpf_ctx_range(struct __sk_buff, data):
8612 	case bpf_ctx_range(struct __sk_buff, data_end):
8613 		if (!bpf_capable())
8614 			return false;
8615 		break;
8616 	}
8617 
8618 	if (type == BPF_WRITE) {
8619 		switch (off) {
8620 		case bpf_ctx_range(struct __sk_buff, mark):
8621 		case bpf_ctx_range(struct __sk_buff, priority):
8622 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8623 			break;
8624 		case bpf_ctx_range(struct __sk_buff, tstamp):
8625 			if (!bpf_capable())
8626 				return false;
8627 			break;
8628 		default:
8629 			return false;
8630 		}
8631 	}
8632 
8633 	switch (off) {
8634 	case bpf_ctx_range(struct __sk_buff, data):
8635 		info->reg_type = PTR_TO_PACKET;
8636 		break;
8637 	case bpf_ctx_range(struct __sk_buff, data_end):
8638 		info->reg_type = PTR_TO_PACKET_END;
8639 		break;
8640 	}
8641 
8642 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8643 }
8644 
lwt_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8645 static bool lwt_is_valid_access(int off, int size,
8646 				enum bpf_access_type type,
8647 				const struct bpf_prog *prog,
8648 				struct bpf_insn_access_aux *info)
8649 {
8650 	switch (off) {
8651 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8652 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8653 	case bpf_ctx_range(struct __sk_buff, data_meta):
8654 	case bpf_ctx_range(struct __sk_buff, tstamp):
8655 	case bpf_ctx_range(struct __sk_buff, wire_len):
8656 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8657 		return false;
8658 	}
8659 
8660 	if (type == BPF_WRITE) {
8661 		switch (off) {
8662 		case bpf_ctx_range(struct __sk_buff, mark):
8663 		case bpf_ctx_range(struct __sk_buff, priority):
8664 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8665 			break;
8666 		default:
8667 			return false;
8668 		}
8669 	}
8670 
8671 	switch (off) {
8672 	case bpf_ctx_range(struct __sk_buff, data):
8673 		info->reg_type = PTR_TO_PACKET;
8674 		break;
8675 	case bpf_ctx_range(struct __sk_buff, data_end):
8676 		info->reg_type = PTR_TO_PACKET_END;
8677 		break;
8678 	}
8679 
8680 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8681 }
8682 
8683 /* Attach type specific accesses */
__sock_filter_check_attach_type(int off,enum bpf_access_type access_type,enum bpf_attach_type attach_type)8684 static bool __sock_filter_check_attach_type(int off,
8685 					    enum bpf_access_type access_type,
8686 					    enum bpf_attach_type attach_type)
8687 {
8688 	switch (off) {
8689 	case offsetof(struct bpf_sock, bound_dev_if):
8690 	case offsetof(struct bpf_sock, mark):
8691 	case offsetof(struct bpf_sock, priority):
8692 		switch (attach_type) {
8693 		case BPF_CGROUP_INET_SOCK_CREATE:
8694 		case BPF_CGROUP_INET_SOCK_RELEASE:
8695 			goto full_access;
8696 		default:
8697 			return false;
8698 		}
8699 	case bpf_ctx_range(struct bpf_sock, src_ip4):
8700 		switch (attach_type) {
8701 		case BPF_CGROUP_INET4_POST_BIND:
8702 			goto read_only;
8703 		default:
8704 			return false;
8705 		}
8706 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8707 		switch (attach_type) {
8708 		case BPF_CGROUP_INET6_POST_BIND:
8709 			goto read_only;
8710 		default:
8711 			return false;
8712 		}
8713 	case bpf_ctx_range(struct bpf_sock, src_port):
8714 		switch (attach_type) {
8715 		case BPF_CGROUP_INET4_POST_BIND:
8716 		case BPF_CGROUP_INET6_POST_BIND:
8717 			goto read_only;
8718 		default:
8719 			return false;
8720 		}
8721 	}
8722 read_only:
8723 	return access_type == BPF_READ;
8724 full_access:
8725 	return true;
8726 }
8727 
bpf_sock_common_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8728 bool bpf_sock_common_is_valid_access(int off, int size,
8729 				     enum bpf_access_type type,
8730 				     struct bpf_insn_access_aux *info)
8731 {
8732 	switch (off) {
8733 	case bpf_ctx_range_till(struct bpf_sock, type, priority):
8734 		return false;
8735 	default:
8736 		return bpf_sock_is_valid_access(off, size, type, info);
8737 	}
8738 }
8739 
bpf_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8740 bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
8741 			      struct bpf_insn_access_aux *info)
8742 {
8743 	const int size_default = sizeof(__u32);
8744 	int field_size;
8745 
8746 	if (off < 0 || off >= sizeof(struct bpf_sock))
8747 		return false;
8748 	if (off % size != 0)
8749 		return false;
8750 
8751 	switch (off) {
8752 	case offsetof(struct bpf_sock, state):
8753 	case offsetof(struct bpf_sock, family):
8754 	case offsetof(struct bpf_sock, type):
8755 	case offsetof(struct bpf_sock, protocol):
8756 	case offsetof(struct bpf_sock, src_port):
8757 	case offsetof(struct bpf_sock, rx_queue_mapping):
8758 	case bpf_ctx_range(struct bpf_sock, src_ip4):
8759 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8760 	case bpf_ctx_range(struct bpf_sock, dst_ip4):
8761 	case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
8762 		bpf_ctx_record_field_size(info, size_default);
8763 		return bpf_ctx_narrow_access_ok(off, size, size_default);
8764 	case bpf_ctx_range(struct bpf_sock, dst_port):
8765 		field_size = size == size_default ?
8766 			size_default : sizeof_field(struct bpf_sock, dst_port);
8767 		bpf_ctx_record_field_size(info, field_size);
8768 		return bpf_ctx_narrow_access_ok(off, size, field_size);
8769 	case offsetofend(struct bpf_sock, dst_port) ...
8770 	     offsetof(struct bpf_sock, dst_ip4) - 1:
8771 		return false;
8772 	}
8773 
8774 	return size == size_default;
8775 }
8776 
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)8777 static bool sock_filter_is_valid_access(int off, int size,
8778 					enum bpf_access_type type,
8779 					const struct bpf_prog *prog,
8780 					struct bpf_insn_access_aux *info)
8781 {
8782 	if (!bpf_sock_is_valid_access(off, size, type, info))
8783 		return false;
8784 	return __sock_filter_check_attach_type(off, type,
8785 					       prog->expected_attach_type);
8786 }
8787 
bpf_noop_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8788 static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write,
8789 			     const struct bpf_prog *prog)
8790 {
8791 	/* Neither direct read nor direct write requires any preliminary
8792 	 * action.
8793 	 */
8794 	return 0;
8795 }
8796 
bpf_unclone_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog,int drop_verdict)8797 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
8798 				const struct bpf_prog *prog, int drop_verdict)
8799 {
8800 	struct bpf_insn *insn = insn_buf;
8801 
8802 	if (!direct_write)
8803 		return 0;
8804 
8805 	/* if (!skb->cloned)
8806 	 *       goto start;
8807 	 *
8808 	 * (Fast-path, otherwise approximation that we might be
8809 	 *  a clone, do the rest in helper.)
8810 	 */
8811 	*insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET);
8812 	*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
8813 	*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
8814 
8815 	/* ret = bpf_skb_pull_data(skb, 0); */
8816 	*insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
8817 	*insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
8818 	*insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
8819 			       BPF_FUNC_skb_pull_data);
8820 	/* if (!ret)
8821 	 *      goto restore;
8822 	 * return TC_ACT_SHOT;
8823 	 */
8824 	*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
8825 	*insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
8826 	*insn++ = BPF_EXIT_INSN();
8827 
8828 	/* restore: */
8829 	*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
8830 	/* start: */
8831 	*insn++ = prog->insnsi[0];
8832 
8833 	return insn - insn_buf;
8834 }
8835 
bpf_gen_ld_abs(const struct bpf_insn * orig,struct bpf_insn * insn_buf)8836 static int bpf_gen_ld_abs(const struct bpf_insn *orig,
8837 			  struct bpf_insn *insn_buf)
8838 {
8839 	bool indirect = BPF_MODE(orig->code) == BPF_IND;
8840 	struct bpf_insn *insn = insn_buf;
8841 
8842 	if (!indirect) {
8843 		*insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
8844 	} else {
8845 		*insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
8846 		if (orig->imm)
8847 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
8848 	}
8849 	/* We're guaranteed here that CTX is in R6. */
8850 	*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);
8851 
8852 	switch (BPF_SIZE(orig->code)) {
8853 	case BPF_B:
8854 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
8855 		break;
8856 	case BPF_H:
8857 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
8858 		break;
8859 	case BPF_W:
8860 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
8861 		break;
8862 	}
8863 
8864 	*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
8865 	*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
8866 	*insn++ = BPF_EXIT_INSN();
8867 
8868 	return insn - insn_buf;
8869 }
8870 
tc_cls_act_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8871 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
8872 			       const struct bpf_prog *prog)
8873 {
8874 	return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
8875 }
8876 
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)8877 static bool tc_cls_act_is_valid_access(int off, int size,
8878 				       enum bpf_access_type type,
8879 				       const struct bpf_prog *prog,
8880 				       struct bpf_insn_access_aux *info)
8881 {
8882 	if (type == BPF_WRITE) {
8883 		switch (off) {
8884 		case bpf_ctx_range(struct __sk_buff, mark):
8885 		case bpf_ctx_range(struct __sk_buff, tc_index):
8886 		case bpf_ctx_range(struct __sk_buff, priority):
8887 		case bpf_ctx_range(struct __sk_buff, tc_classid):
8888 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8889 		case bpf_ctx_range(struct __sk_buff, tstamp):
8890 		case bpf_ctx_range(struct __sk_buff, queue_mapping):
8891 			break;
8892 		default:
8893 			return false;
8894 		}
8895 	}
8896 
8897 	switch (off) {
8898 	case bpf_ctx_range(struct __sk_buff, data):
8899 		info->reg_type = PTR_TO_PACKET;
8900 		break;
8901 	case bpf_ctx_range(struct __sk_buff, data_meta):
8902 		info->reg_type = PTR_TO_PACKET_META;
8903 		break;
8904 	case bpf_ctx_range(struct __sk_buff, data_end):
8905 		info->reg_type = PTR_TO_PACKET_END;
8906 		break;
8907 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8908 		return false;
8909 	case offsetof(struct __sk_buff, tstamp_type):
8910 		/* The convert_ctx_access() on reading and writing
8911 		 * __sk_buff->tstamp depends on whether the bpf prog
8912 		 * has used __sk_buff->tstamp_type or not.
8913 		 * Thus, we need to set prog->tstamp_type_access
8914 		 * earlier during is_valid_access() here.
8915 		 */
8916 		((struct bpf_prog *)prog)->tstamp_type_access = 1;
8917 		return size == sizeof(__u8);
8918 	}
8919 
8920 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8921 }
8922 
8923 DEFINE_MUTEX(nf_conn_btf_access_lock);
8924 EXPORT_SYMBOL_GPL(nf_conn_btf_access_lock);
8925 
8926 int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
8927 			      const struct bpf_reg_state *reg,
8928 			      int off, int size);
8929 EXPORT_SYMBOL_GPL(nfct_btf_struct_access);
8930 
tc_cls_act_btf_struct_access(struct bpf_verifier_log * log,const struct bpf_reg_state * reg,int off,int size)8931 static int tc_cls_act_btf_struct_access(struct bpf_verifier_log *log,
8932 					const struct bpf_reg_state *reg,
8933 					int off, int size)
8934 {
8935 	int ret = -EACCES;
8936 
8937 	mutex_lock(&nf_conn_btf_access_lock);
8938 	if (nfct_btf_struct_access)
8939 		ret = nfct_btf_struct_access(log, reg, off, size);
8940 	mutex_unlock(&nf_conn_btf_access_lock);
8941 
8942 	return ret;
8943 }
8944 
__is_valid_xdp_access(int off,int size)8945 static bool __is_valid_xdp_access(int off, int size)
8946 {
8947 	if (off < 0 || off >= sizeof(struct xdp_md))
8948 		return false;
8949 	if (off % size != 0)
8950 		return false;
8951 	if (size != sizeof(__u32))
8952 		return false;
8953 
8954 	return true;
8955 }
8956 
xdp_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8957 static bool xdp_is_valid_access(int off, int size,
8958 				enum bpf_access_type type,
8959 				const struct bpf_prog *prog,
8960 				struct bpf_insn_access_aux *info)
8961 {
8962 	if (prog->expected_attach_type != BPF_XDP_DEVMAP) {
8963 		switch (off) {
8964 		case offsetof(struct xdp_md, egress_ifindex):
8965 			return false;
8966 		}
8967 	}
8968 
8969 	if (type == BPF_WRITE) {
8970 		if (bpf_prog_is_offloaded(prog->aux)) {
8971 			switch (off) {
8972 			case offsetof(struct xdp_md, rx_queue_index):
8973 				return __is_valid_xdp_access(off, size);
8974 			}
8975 		}
8976 		return false;
8977 	}
8978 
8979 	switch (off) {
8980 	case offsetof(struct xdp_md, data):
8981 		info->reg_type = PTR_TO_PACKET;
8982 		break;
8983 	case offsetof(struct xdp_md, data_meta):
8984 		info->reg_type = PTR_TO_PACKET_META;
8985 		break;
8986 	case offsetof(struct xdp_md, data_end):
8987 		info->reg_type = PTR_TO_PACKET_END;
8988 		break;
8989 	}
8990 
8991 	return __is_valid_xdp_access(off, size);
8992 }
8993 
bpf_warn_invalid_xdp_action(struct net_device * dev,struct bpf_prog * prog,u32 act)8994 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)
8995 {
8996 	const u32 act_max = XDP_REDIRECT;
8997 
8998 	pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
8999 		     act > act_max ? "Illegal" : "Driver unsupported",
9000 		     act, prog->aux->name, prog->aux->id, dev ? dev->name : "N/A");
9001 }
9002 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
9003 
xdp_btf_struct_access(struct bpf_verifier_log * log,const struct bpf_reg_state * reg,int off,int size)9004 static int xdp_btf_struct_access(struct bpf_verifier_log *log,
9005 				 const struct bpf_reg_state *reg,
9006 				 int off, int size)
9007 {
9008 	int ret = -EACCES;
9009 
9010 	mutex_lock(&nf_conn_btf_access_lock);
9011 	if (nfct_btf_struct_access)
9012 		ret = nfct_btf_struct_access(log, reg, off, size);
9013 	mutex_unlock(&nf_conn_btf_access_lock);
9014 
9015 	return ret;
9016 }
9017 
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)9018 static bool sock_addr_is_valid_access(int off, int size,
9019 				      enum bpf_access_type type,
9020 				      const struct bpf_prog *prog,
9021 				      struct bpf_insn_access_aux *info)
9022 {
9023 	const int size_default = sizeof(__u32);
9024 
9025 	if (off < 0 || off >= sizeof(struct bpf_sock_addr))
9026 		return false;
9027 	if (off % size != 0)
9028 		return false;
9029 
9030 	/* Disallow access to IPv6 fields from IPv4 contex and vise
9031 	 * versa.
9032 	 */
9033 	switch (off) {
9034 	case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
9035 		switch (prog->expected_attach_type) {
9036 		case BPF_CGROUP_INET4_BIND:
9037 		case BPF_CGROUP_INET4_CONNECT:
9038 		case BPF_CGROUP_INET4_GETPEERNAME:
9039 		case BPF_CGROUP_INET4_GETSOCKNAME:
9040 		case BPF_CGROUP_UDP4_SENDMSG:
9041 		case BPF_CGROUP_UDP4_RECVMSG:
9042 			break;
9043 		default:
9044 			return false;
9045 		}
9046 		break;
9047 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
9048 		switch (prog->expected_attach_type) {
9049 		case BPF_CGROUP_INET6_BIND:
9050 		case BPF_CGROUP_INET6_CONNECT:
9051 		case BPF_CGROUP_INET6_GETPEERNAME:
9052 		case BPF_CGROUP_INET6_GETSOCKNAME:
9053 		case BPF_CGROUP_UDP6_SENDMSG:
9054 		case BPF_CGROUP_UDP6_RECVMSG:
9055 			break;
9056 		default:
9057 			return false;
9058 		}
9059 		break;
9060 	case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
9061 		switch (prog->expected_attach_type) {
9062 		case BPF_CGROUP_UDP4_SENDMSG:
9063 			break;
9064 		default:
9065 			return false;
9066 		}
9067 		break;
9068 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
9069 				msg_src_ip6[3]):
9070 		switch (prog->expected_attach_type) {
9071 		case BPF_CGROUP_UDP6_SENDMSG:
9072 			break;
9073 		default:
9074 			return false;
9075 		}
9076 		break;
9077 	}
9078 
9079 	switch (off) {
9080 	case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
9081 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
9082 	case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
9083 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
9084 				msg_src_ip6[3]):
9085 	case bpf_ctx_range(struct bpf_sock_addr, user_port):
9086 		if (type == BPF_READ) {
9087 			bpf_ctx_record_field_size(info, size_default);
9088 
9089 			if (bpf_ctx_wide_access_ok(off, size,
9090 						   struct bpf_sock_addr,
9091 						   user_ip6))
9092 				return true;
9093 
9094 			if (bpf_ctx_wide_access_ok(off, size,
9095 						   struct bpf_sock_addr,
9096 						   msg_src_ip6))
9097 				return true;
9098 
9099 			if (!bpf_ctx_narrow_access_ok(off, size, size_default))
9100 				return false;
9101 		} else {
9102 			if (bpf_ctx_wide_access_ok(off, size,
9103 						   struct bpf_sock_addr,
9104 						   user_ip6))
9105 				return true;
9106 
9107 			if (bpf_ctx_wide_access_ok(off, size,
9108 						   struct bpf_sock_addr,
9109 						   msg_src_ip6))
9110 				return true;
9111 
9112 			if (size != size_default)
9113 				return false;
9114 		}
9115 		break;
9116 	case offsetof(struct bpf_sock_addr, sk):
9117 		if (type != BPF_READ)
9118 			return false;
9119 		if (size != sizeof(__u64))
9120 			return false;
9121 		info->reg_type = PTR_TO_SOCKET;
9122 		break;
9123 	default:
9124 		if (type == BPF_READ) {
9125 			if (size != size_default)
9126 				return false;
9127 		} else {
9128 			return false;
9129 		}
9130 	}
9131 
9132 	return true;
9133 }
9134 
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)9135 static bool sock_ops_is_valid_access(int off, int size,
9136 				     enum bpf_access_type type,
9137 				     const struct bpf_prog *prog,
9138 				     struct bpf_insn_access_aux *info)
9139 {
9140 	const int size_default = sizeof(__u32);
9141 
9142 	if (off < 0 || off >= sizeof(struct bpf_sock_ops))
9143 		return false;
9144 
9145 	/* The verifier guarantees that size > 0. */
9146 	if (off % size != 0)
9147 		return false;
9148 
9149 	if (type == BPF_WRITE) {
9150 		switch (off) {
9151 		case offsetof(struct bpf_sock_ops, reply):
9152 		case offsetof(struct bpf_sock_ops, sk_txhash):
9153 			if (size != size_default)
9154 				return false;
9155 			break;
9156 		default:
9157 			return false;
9158 		}
9159 	} else {
9160 		switch (off) {
9161 		case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
9162 					bytes_acked):
9163 			if (size != sizeof(__u64))
9164 				return false;
9165 			break;
9166 		case offsetof(struct bpf_sock_ops, sk):
9167 			if (size != sizeof(__u64))
9168 				return false;
9169 			info->reg_type = PTR_TO_SOCKET_OR_NULL;
9170 			break;
9171 		case offsetof(struct bpf_sock_ops, skb_data):
9172 			if (size != sizeof(__u64))
9173 				return false;
9174 			info->reg_type = PTR_TO_PACKET;
9175 			break;
9176 		case offsetof(struct bpf_sock_ops, skb_data_end):
9177 			if (size != sizeof(__u64))
9178 				return false;
9179 			info->reg_type = PTR_TO_PACKET_END;
9180 			break;
9181 		case offsetof(struct bpf_sock_ops, skb_tcp_flags):
9182 			bpf_ctx_record_field_size(info, size_default);
9183 			return bpf_ctx_narrow_access_ok(off, size,
9184 							size_default);
9185 		case offsetof(struct bpf_sock_ops, skb_hwtstamp):
9186 			if (size != sizeof(__u64))
9187 				return false;
9188 			break;
9189 		default:
9190 			if (size != size_default)
9191 				return false;
9192 			break;
9193 		}
9194 	}
9195 
9196 	return true;
9197 }
9198 
sk_skb_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)9199 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
9200 			   const struct bpf_prog *prog)
9201 {
9202 	return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
9203 }
9204 
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)9205 static bool sk_skb_is_valid_access(int off, int size,
9206 				   enum bpf_access_type type,
9207 				   const struct bpf_prog *prog,
9208 				   struct bpf_insn_access_aux *info)
9209 {
9210 	switch (off) {
9211 	case bpf_ctx_range(struct __sk_buff, tc_classid):
9212 	case bpf_ctx_range(struct __sk_buff, data_meta):
9213 	case bpf_ctx_range(struct __sk_buff, tstamp):
9214 	case bpf_ctx_range(struct __sk_buff, wire_len):
9215 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
9216 		return false;
9217 	}
9218 
9219 	if (type == BPF_WRITE) {
9220 		switch (off) {
9221 		case bpf_ctx_range(struct __sk_buff, tc_index):
9222 		case bpf_ctx_range(struct __sk_buff, priority):
9223 			break;
9224 		default:
9225 			return false;
9226 		}
9227 	}
9228 
9229 	switch (off) {
9230 	case bpf_ctx_range(struct __sk_buff, mark):
9231 		return false;
9232 	case bpf_ctx_range(struct __sk_buff, data):
9233 		info->reg_type = PTR_TO_PACKET;
9234 		break;
9235 	case bpf_ctx_range(struct __sk_buff, data_end):
9236 		info->reg_type = PTR_TO_PACKET_END;
9237 		break;
9238 	}
9239 
9240 	return bpf_skb_is_valid_access(off, size, type, prog, info);
9241 }
9242 
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)9243 static bool sk_msg_is_valid_access(int off, int size,
9244 				   enum bpf_access_type type,
9245 				   const struct bpf_prog *prog,
9246 				   struct bpf_insn_access_aux *info)
9247 {
9248 	if (type == BPF_WRITE)
9249 		return false;
9250 
9251 	if (off % size != 0)
9252 		return false;
9253 
9254 	switch (off) {
9255 	case offsetof(struct sk_msg_md, data):
9256 		info->reg_type = PTR_TO_PACKET;
9257 		if (size != sizeof(__u64))
9258 			return false;
9259 		break;
9260 	case offsetof(struct sk_msg_md, data_end):
9261 		info->reg_type = PTR_TO_PACKET_END;
9262 		if (size != sizeof(__u64))
9263 			return false;
9264 		break;
9265 	case offsetof(struct sk_msg_md, sk):
9266 		if (size != sizeof(__u64))
9267 			return false;
9268 		info->reg_type = PTR_TO_SOCKET;
9269 		break;
9270 	case bpf_ctx_range(struct sk_msg_md, family):
9271 	case bpf_ctx_range(struct sk_msg_md, remote_ip4):
9272 	case bpf_ctx_range(struct sk_msg_md, local_ip4):
9273 	case bpf_ctx_range_till(struct sk_msg_md, remote_ip6[0], remote_ip6[3]):
9274 	case bpf_ctx_range_till(struct sk_msg_md, local_ip6[0], local_ip6[3]):
9275 	case bpf_ctx_range(struct sk_msg_md, remote_port):
9276 	case bpf_ctx_range(struct sk_msg_md, local_port):
9277 	case bpf_ctx_range(struct sk_msg_md, size):
9278 		if (size != sizeof(__u32))
9279 			return false;
9280 		break;
9281 	default:
9282 		return false;
9283 	}
9284 	return true;
9285 }
9286 
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)9287 static bool flow_dissector_is_valid_access(int off, int size,
9288 					   enum bpf_access_type type,
9289 					   const struct bpf_prog *prog,
9290 					   struct bpf_insn_access_aux *info)
9291 {
9292 	const int size_default = sizeof(__u32);
9293 
9294 	if (off < 0 || off >= sizeof(struct __sk_buff))
9295 		return false;
9296 
9297 	if (type == BPF_WRITE)
9298 		return false;
9299 
9300 	switch (off) {
9301 	case bpf_ctx_range(struct __sk_buff, data):
9302 		if (size != size_default)
9303 			return false;
9304 		info->reg_type = PTR_TO_PACKET;
9305 		return true;
9306 	case bpf_ctx_range(struct __sk_buff, data_end):
9307 		if (size != size_default)
9308 			return false;
9309 		info->reg_type = PTR_TO_PACKET_END;
9310 		return true;
9311 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
9312 		if (size != sizeof(__u64))
9313 			return false;
9314 		info->reg_type = PTR_TO_FLOW_KEYS;
9315 		return true;
9316 	default:
9317 		return false;
9318 	}
9319 }
9320 
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)9321 static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type,
9322 					     const struct bpf_insn *si,
9323 					     struct bpf_insn *insn_buf,
9324 					     struct bpf_prog *prog,
9325 					     u32 *target_size)
9326 
9327 {
9328 	struct bpf_insn *insn = insn_buf;
9329 
9330 	switch (si->off) {
9331 	case offsetof(struct __sk_buff, data):
9332 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data),
9333 				      si->dst_reg, si->src_reg,
9334 				      offsetof(struct bpf_flow_dissector, data));
9335 		break;
9336 
9337 	case offsetof(struct __sk_buff, data_end):
9338 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data_end),
9339 				      si->dst_reg, si->src_reg,
9340 				      offsetof(struct bpf_flow_dissector, data_end));
9341 		break;
9342 
9343 	case offsetof(struct __sk_buff, flow_keys):
9344 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, flow_keys),
9345 				      si->dst_reg, si->src_reg,
9346 				      offsetof(struct bpf_flow_dissector, flow_keys));
9347 		break;
9348 	}
9349 
9350 	return insn - insn_buf;
9351 }
9352 
bpf_convert_tstamp_type_read(const struct bpf_insn * si,struct bpf_insn * insn)9353 static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si,
9354 						     struct bpf_insn *insn)
9355 {
9356 	__u8 value_reg = si->dst_reg;
9357 	__u8 skb_reg = si->src_reg;
9358 	/* AX is needed because src_reg and dst_reg could be the same */
9359 	__u8 tmp_reg = BPF_REG_AX;
9360 
9361 	*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg,
9362 			      SKB_BF_MONO_TC_OFFSET);
9363 	*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg,
9364 				SKB_MONO_DELIVERY_TIME_MASK, 2);
9365 	*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_UNSPEC);
9366 	*insn++ = BPF_JMP_A(1);
9367 	*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_DELIVERY_MONO);
9368 
9369 	return insn;
9370 }
9371 
bpf_convert_shinfo_access(__u8 dst_reg,__u8 skb_reg,struct bpf_insn * insn)9372 static struct bpf_insn *bpf_convert_shinfo_access(__u8 dst_reg, __u8 skb_reg,
9373 						  struct bpf_insn *insn)
9374 {
9375 	/* si->dst_reg = skb_shinfo(SKB); */
9376 #ifdef NET_SKBUFF_DATA_USES_OFFSET
9377 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
9378 			      BPF_REG_AX, skb_reg,
9379 			      offsetof(struct sk_buff, end));
9380 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, head),
9381 			      dst_reg, skb_reg,
9382 			      offsetof(struct sk_buff, head));
9383 	*insn++ = BPF_ALU64_REG(BPF_ADD, dst_reg, BPF_REG_AX);
9384 #else
9385 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
9386 			      dst_reg, skb_reg,
9387 			      offsetof(struct sk_buff, end));
9388 #endif
9389 
9390 	return insn;
9391 }
9392 
bpf_convert_tstamp_read(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)9393 static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog,
9394 						const struct bpf_insn *si,
9395 						struct bpf_insn *insn)
9396 {
9397 	__u8 value_reg = si->dst_reg;
9398 	__u8 skb_reg = si->src_reg;
9399 
9400 #ifdef CONFIG_NET_XGRESS
9401 	/* If the tstamp_type is read,
9402 	 * the bpf prog is aware the tstamp could have delivery time.
9403 	 * Thus, read skb->tstamp as is if tstamp_type_access is true.
9404 	 */
9405 	if (!prog->tstamp_type_access) {
9406 		/* AX is needed because src_reg and dst_reg could be the same */
9407 		__u8 tmp_reg = BPF_REG_AX;
9408 
9409 		*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
9410 		*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg,
9411 					TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK);
9412 		*insn++ = BPF_JMP32_IMM(BPF_JNE, tmp_reg,
9413 					TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK, 2);
9414 		/* skb->tc_at_ingress && skb->mono_delivery_time,
9415 		 * read 0 as the (rcv) timestamp.
9416 		 */
9417 		*insn++ = BPF_MOV64_IMM(value_reg, 0);
9418 		*insn++ = BPF_JMP_A(1);
9419 	}
9420 #endif
9421 
9422 	*insn++ = BPF_LDX_MEM(BPF_DW, value_reg, skb_reg,
9423 			      offsetof(struct sk_buff, tstamp));
9424 	return insn;
9425 }
9426 
bpf_convert_tstamp_write(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)9427 static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog,
9428 						 const struct bpf_insn *si,
9429 						 struct bpf_insn *insn)
9430 {
9431 	__u8 value_reg = si->src_reg;
9432 	__u8 skb_reg = si->dst_reg;
9433 
9434 #ifdef CONFIG_NET_XGRESS
9435 	/* If the tstamp_type is read,
9436 	 * the bpf prog is aware the tstamp could have delivery time.
9437 	 * Thus, write skb->tstamp as is if tstamp_type_access is true.
9438 	 * Otherwise, writing at ingress will have to clear the
9439 	 * mono_delivery_time bit also.
9440 	 */
9441 	if (!prog->tstamp_type_access) {
9442 		__u8 tmp_reg = BPF_REG_AX;
9443 
9444 		*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, SKB_BF_MONO_TC_OFFSET);
9445 		/* Writing __sk_buff->tstamp as ingress, goto <clear> */
9446 		*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, TC_AT_INGRESS_MASK, 1);
9447 		/* goto <store> */
9448 		*insn++ = BPF_JMP_A(2);
9449 		/* <clear>: mono_delivery_time */
9450 		*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_MONO_DELIVERY_TIME_MASK);
9451 		*insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, SKB_BF_MONO_TC_OFFSET);
9452 	}
9453 #endif
9454 
9455 	/* <store>: skb->tstamp = tstamp */
9456 	*insn++ = BPF_RAW_INSN(BPF_CLASS(si->code) | BPF_DW | BPF_MEM,
9457 			       skb_reg, value_reg, offsetof(struct sk_buff, tstamp), si->imm);
9458 	return insn;
9459 }
9460 
9461 #define BPF_EMIT_STORE(size, si, off)					\
9462 	BPF_RAW_INSN(BPF_CLASS((si)->code) | (size) | BPF_MEM,		\
9463 		     (si)->dst_reg, (si)->src_reg, (off), (si)->imm)
9464 
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)9465 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
9466 				  const struct bpf_insn *si,
9467 				  struct bpf_insn *insn_buf,
9468 				  struct bpf_prog *prog, u32 *target_size)
9469 {
9470 	struct bpf_insn *insn = insn_buf;
9471 	int off;
9472 
9473 	switch (si->off) {
9474 	case offsetof(struct __sk_buff, len):
9475 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9476 				      bpf_target_off(struct sk_buff, len, 4,
9477 						     target_size));
9478 		break;
9479 
9480 	case offsetof(struct __sk_buff, protocol):
9481 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9482 				      bpf_target_off(struct sk_buff, protocol, 2,
9483 						     target_size));
9484 		break;
9485 
9486 	case offsetof(struct __sk_buff, vlan_proto):
9487 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9488 				      bpf_target_off(struct sk_buff, vlan_proto, 2,
9489 						     target_size));
9490 		break;
9491 
9492 	case offsetof(struct __sk_buff, priority):
9493 		if (type == BPF_WRITE)
9494 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9495 						 bpf_target_off(struct sk_buff, priority, 4,
9496 								target_size));
9497 		else
9498 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9499 					      bpf_target_off(struct sk_buff, priority, 4,
9500 							     target_size));
9501 		break;
9502 
9503 	case offsetof(struct __sk_buff, ingress_ifindex):
9504 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9505 				      bpf_target_off(struct sk_buff, skb_iif, 4,
9506 						     target_size));
9507 		break;
9508 
9509 	case offsetof(struct __sk_buff, ifindex):
9510 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
9511 				      si->dst_reg, si->src_reg,
9512 				      offsetof(struct sk_buff, dev));
9513 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9514 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9515 				      bpf_target_off(struct net_device, ifindex, 4,
9516 						     target_size));
9517 		break;
9518 
9519 	case offsetof(struct __sk_buff, hash):
9520 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9521 				      bpf_target_off(struct sk_buff, hash, 4,
9522 						     target_size));
9523 		break;
9524 
9525 	case offsetof(struct __sk_buff, mark):
9526 		if (type == BPF_WRITE)
9527 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9528 						 bpf_target_off(struct sk_buff, mark, 4,
9529 								target_size));
9530 		else
9531 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9532 					      bpf_target_off(struct sk_buff, mark, 4,
9533 							     target_size));
9534 		break;
9535 
9536 	case offsetof(struct __sk_buff, pkt_type):
9537 		*target_size = 1;
9538 		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
9539 				      PKT_TYPE_OFFSET);
9540 		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
9541 #ifdef __BIG_ENDIAN_BITFIELD
9542 		*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
9543 #endif
9544 		break;
9545 
9546 	case offsetof(struct __sk_buff, queue_mapping):
9547 		if (type == BPF_WRITE) {
9548 			u32 off = bpf_target_off(struct sk_buff, queue_mapping, 2, target_size);
9549 
9550 			if (BPF_CLASS(si->code) == BPF_ST && si->imm >= NO_QUEUE_MAPPING) {
9551 				*insn++ = BPF_JMP_A(0); /* noop */
9552 				break;
9553 			}
9554 
9555 			if (BPF_CLASS(si->code) == BPF_STX)
9556 				*insn++ = BPF_JMP_IMM(BPF_JGE, si->src_reg, NO_QUEUE_MAPPING, 1);
9557 			*insn++ = BPF_EMIT_STORE(BPF_H, si, off);
9558 		} else {
9559 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9560 					      bpf_target_off(struct sk_buff,
9561 							     queue_mapping,
9562 							     2, target_size));
9563 		}
9564 		break;
9565 
9566 	case offsetof(struct __sk_buff, vlan_present):
9567 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9568 				      bpf_target_off(struct sk_buff,
9569 						     vlan_all, 4, target_size));
9570 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9571 		*insn++ = BPF_ALU32_IMM(BPF_MOV, si->dst_reg, 1);
9572 		break;
9573 
9574 	case offsetof(struct __sk_buff, vlan_tci):
9575 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9576 				      bpf_target_off(struct sk_buff, vlan_tci, 2,
9577 						     target_size));
9578 		break;
9579 
9580 	case offsetof(struct __sk_buff, cb[0]) ...
9581 	     offsetofend(struct __sk_buff, cb[4]) - 1:
9582 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, data) < 20);
9583 		BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
9584 			      offsetof(struct qdisc_skb_cb, data)) %
9585 			     sizeof(__u64));
9586 
9587 		prog->cb_access = 1;
9588 		off  = si->off;
9589 		off -= offsetof(struct __sk_buff, cb[0]);
9590 		off += offsetof(struct sk_buff, cb);
9591 		off += offsetof(struct qdisc_skb_cb, data);
9592 		if (type == BPF_WRITE)
9593 			*insn++ = BPF_EMIT_STORE(BPF_SIZE(si->code), si, off);
9594 		else
9595 			*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
9596 					      si->src_reg, off);
9597 		break;
9598 
9599 	case offsetof(struct __sk_buff, tc_classid):
9600 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, tc_classid) != 2);
9601 
9602 		off  = si->off;
9603 		off -= offsetof(struct __sk_buff, tc_classid);
9604 		off += offsetof(struct sk_buff, cb);
9605 		off += offsetof(struct qdisc_skb_cb, tc_classid);
9606 		*target_size = 2;
9607 		if (type == BPF_WRITE)
9608 			*insn++ = BPF_EMIT_STORE(BPF_H, si, off);
9609 		else
9610 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
9611 					      si->src_reg, off);
9612 		break;
9613 
9614 	case offsetof(struct __sk_buff, data):
9615 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
9616 				      si->dst_reg, si->src_reg,
9617 				      offsetof(struct sk_buff, data));
9618 		break;
9619 
9620 	case offsetof(struct __sk_buff, data_meta):
9621 		off  = si->off;
9622 		off -= offsetof(struct __sk_buff, data_meta);
9623 		off += offsetof(struct sk_buff, cb);
9624 		off += offsetof(struct bpf_skb_data_end, data_meta);
9625 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9626 				      si->src_reg, off);
9627 		break;
9628 
9629 	case offsetof(struct __sk_buff, data_end):
9630 		off  = si->off;
9631 		off -= offsetof(struct __sk_buff, data_end);
9632 		off += offsetof(struct sk_buff, cb);
9633 		off += offsetof(struct bpf_skb_data_end, data_end);
9634 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9635 				      si->src_reg, off);
9636 		break;
9637 
9638 	case offsetof(struct __sk_buff, tc_index):
9639 #ifdef CONFIG_NET_SCHED
9640 		if (type == BPF_WRITE)
9641 			*insn++ = BPF_EMIT_STORE(BPF_H, si,
9642 						 bpf_target_off(struct sk_buff, tc_index, 2,
9643 								target_size));
9644 		else
9645 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9646 					      bpf_target_off(struct sk_buff, tc_index, 2,
9647 							     target_size));
9648 #else
9649 		*target_size = 2;
9650 		if (type == BPF_WRITE)
9651 			*insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
9652 		else
9653 			*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9654 #endif
9655 		break;
9656 
9657 	case offsetof(struct __sk_buff, napi_id):
9658 #if defined(CONFIG_NET_RX_BUSY_POLL)
9659 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9660 				      bpf_target_off(struct sk_buff, napi_id, 4,
9661 						     target_size));
9662 		*insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
9663 		*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9664 #else
9665 		*target_size = 4;
9666 		*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9667 #endif
9668 		break;
9669 	case offsetof(struct __sk_buff, family):
9670 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
9671 
9672 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9673 				      si->dst_reg, si->src_reg,
9674 				      offsetof(struct sk_buff, sk));
9675 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9676 				      bpf_target_off(struct sock_common,
9677 						     skc_family,
9678 						     2, target_size));
9679 		break;
9680 	case offsetof(struct __sk_buff, remote_ip4):
9681 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
9682 
9683 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9684 				      si->dst_reg, si->src_reg,
9685 				      offsetof(struct sk_buff, sk));
9686 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9687 				      bpf_target_off(struct sock_common,
9688 						     skc_daddr,
9689 						     4, target_size));
9690 		break;
9691 	case offsetof(struct __sk_buff, local_ip4):
9692 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9693 					  skc_rcv_saddr) != 4);
9694 
9695 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9696 				      si->dst_reg, si->src_reg,
9697 				      offsetof(struct sk_buff, sk));
9698 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9699 				      bpf_target_off(struct sock_common,
9700 						     skc_rcv_saddr,
9701 						     4, target_size));
9702 		break;
9703 	case offsetof(struct __sk_buff, remote_ip6[0]) ...
9704 	     offsetof(struct __sk_buff, remote_ip6[3]):
9705 #if IS_ENABLED(CONFIG_IPV6)
9706 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9707 					  skc_v6_daddr.s6_addr32[0]) != 4);
9708 
9709 		off = si->off;
9710 		off -= offsetof(struct __sk_buff, remote_ip6[0]);
9711 
9712 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9713 				      si->dst_reg, si->src_reg,
9714 				      offsetof(struct sk_buff, sk));
9715 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9716 				      offsetof(struct sock_common,
9717 					       skc_v6_daddr.s6_addr32[0]) +
9718 				      off);
9719 #else
9720 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9721 #endif
9722 		break;
9723 	case offsetof(struct __sk_buff, local_ip6[0]) ...
9724 	     offsetof(struct __sk_buff, local_ip6[3]):
9725 #if IS_ENABLED(CONFIG_IPV6)
9726 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9727 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
9728 
9729 		off = si->off;
9730 		off -= offsetof(struct __sk_buff, local_ip6[0]);
9731 
9732 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9733 				      si->dst_reg, si->src_reg,
9734 				      offsetof(struct sk_buff, sk));
9735 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9736 				      offsetof(struct sock_common,
9737 					       skc_v6_rcv_saddr.s6_addr32[0]) +
9738 				      off);
9739 #else
9740 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9741 #endif
9742 		break;
9743 
9744 	case offsetof(struct __sk_buff, remote_port):
9745 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
9746 
9747 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9748 				      si->dst_reg, si->src_reg,
9749 				      offsetof(struct sk_buff, sk));
9750 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9751 				      bpf_target_off(struct sock_common,
9752 						     skc_dport,
9753 						     2, target_size));
9754 #ifndef __BIG_ENDIAN_BITFIELD
9755 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
9756 #endif
9757 		break;
9758 
9759 	case offsetof(struct __sk_buff, local_port):
9760 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
9761 
9762 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9763 				      si->dst_reg, si->src_reg,
9764 				      offsetof(struct sk_buff, sk));
9765 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9766 				      bpf_target_off(struct sock_common,
9767 						     skc_num, 2, target_size));
9768 		break;
9769 
9770 	case offsetof(struct __sk_buff, tstamp):
9771 		BUILD_BUG_ON(sizeof_field(struct sk_buff, tstamp) != 8);
9772 
9773 		if (type == BPF_WRITE)
9774 			insn = bpf_convert_tstamp_write(prog, si, insn);
9775 		else
9776 			insn = bpf_convert_tstamp_read(prog, si, insn);
9777 		break;
9778 
9779 	case offsetof(struct __sk_buff, tstamp_type):
9780 		insn = bpf_convert_tstamp_type_read(si, insn);
9781 		break;
9782 
9783 	case offsetof(struct __sk_buff, gso_segs):
9784 		insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
9785 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_segs),
9786 				      si->dst_reg, si->dst_reg,
9787 				      bpf_target_off(struct skb_shared_info,
9788 						     gso_segs, 2,
9789 						     target_size));
9790 		break;
9791 	case offsetof(struct __sk_buff, gso_size):
9792 		insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
9793 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_size),
9794 				      si->dst_reg, si->dst_reg,
9795 				      bpf_target_off(struct skb_shared_info,
9796 						     gso_size, 2,
9797 						     target_size));
9798 		break;
9799 	case offsetof(struct __sk_buff, wire_len):
9800 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, pkt_len) != 4);
9801 
9802 		off = si->off;
9803 		off -= offsetof(struct __sk_buff, wire_len);
9804 		off += offsetof(struct sk_buff, cb);
9805 		off += offsetof(struct qdisc_skb_cb, pkt_len);
9806 		*target_size = 4;
9807 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
9808 		break;
9809 
9810 	case offsetof(struct __sk_buff, sk):
9811 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9812 				      si->dst_reg, si->src_reg,
9813 				      offsetof(struct sk_buff, sk));
9814 		break;
9815 	case offsetof(struct __sk_buff, hwtstamp):
9816 		BUILD_BUG_ON(sizeof_field(struct skb_shared_hwtstamps, hwtstamp) != 8);
9817 		BUILD_BUG_ON(offsetof(struct skb_shared_hwtstamps, hwtstamp) != 0);
9818 
9819 		insn = bpf_convert_shinfo_access(si->dst_reg, si->src_reg, insn);
9820 		*insn++ = BPF_LDX_MEM(BPF_DW,
9821 				      si->dst_reg, si->dst_reg,
9822 				      bpf_target_off(struct skb_shared_info,
9823 						     hwtstamps, 8,
9824 						     target_size));
9825 		break;
9826 	}
9827 
9828 	return insn - insn_buf;
9829 }
9830 
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)9831 u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
9832 				const struct bpf_insn *si,
9833 				struct bpf_insn *insn_buf,
9834 				struct bpf_prog *prog, u32 *target_size)
9835 {
9836 	struct bpf_insn *insn = insn_buf;
9837 	int off;
9838 
9839 	switch (si->off) {
9840 	case offsetof(struct bpf_sock, bound_dev_if):
9841 		BUILD_BUG_ON(sizeof_field(struct sock, sk_bound_dev_if) != 4);
9842 
9843 		if (type == BPF_WRITE)
9844 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9845 						 offsetof(struct sock, sk_bound_dev_if));
9846 		else
9847 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9848 				      offsetof(struct sock, sk_bound_dev_if));
9849 		break;
9850 
9851 	case offsetof(struct bpf_sock, mark):
9852 		BUILD_BUG_ON(sizeof_field(struct sock, sk_mark) != 4);
9853 
9854 		if (type == BPF_WRITE)
9855 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9856 						 offsetof(struct sock, sk_mark));
9857 		else
9858 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9859 				      offsetof(struct sock, sk_mark));
9860 		break;
9861 
9862 	case offsetof(struct bpf_sock, priority):
9863 		BUILD_BUG_ON(sizeof_field(struct sock, sk_priority) != 4);
9864 
9865 		if (type == BPF_WRITE)
9866 			*insn++ = BPF_EMIT_STORE(BPF_W, si,
9867 						 offsetof(struct sock, sk_priority));
9868 		else
9869 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9870 				      offsetof(struct sock, sk_priority));
9871 		break;
9872 
9873 	case offsetof(struct bpf_sock, family):
9874 		*insn++ = BPF_LDX_MEM(
9875 			BPF_FIELD_SIZEOF(struct sock_common, skc_family),
9876 			si->dst_reg, si->src_reg,
9877 			bpf_target_off(struct sock_common,
9878 				       skc_family,
9879 				       sizeof_field(struct sock_common,
9880 						    skc_family),
9881 				       target_size));
9882 		break;
9883 
9884 	case offsetof(struct bpf_sock, type):
9885 		*insn++ = BPF_LDX_MEM(
9886 			BPF_FIELD_SIZEOF(struct sock, sk_type),
9887 			si->dst_reg, si->src_reg,
9888 			bpf_target_off(struct sock, sk_type,
9889 				       sizeof_field(struct sock, sk_type),
9890 				       target_size));
9891 		break;
9892 
9893 	case offsetof(struct bpf_sock, protocol):
9894 		*insn++ = BPF_LDX_MEM(
9895 			BPF_FIELD_SIZEOF(struct sock, sk_protocol),
9896 			si->dst_reg, si->src_reg,
9897 			bpf_target_off(struct sock, sk_protocol,
9898 				       sizeof_field(struct sock, sk_protocol),
9899 				       target_size));
9900 		break;
9901 
9902 	case offsetof(struct bpf_sock, src_ip4):
9903 		*insn++ = BPF_LDX_MEM(
9904 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9905 			bpf_target_off(struct sock_common, skc_rcv_saddr,
9906 				       sizeof_field(struct sock_common,
9907 						    skc_rcv_saddr),
9908 				       target_size));
9909 		break;
9910 
9911 	case offsetof(struct bpf_sock, dst_ip4):
9912 		*insn++ = BPF_LDX_MEM(
9913 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9914 			bpf_target_off(struct sock_common, skc_daddr,
9915 				       sizeof_field(struct sock_common,
9916 						    skc_daddr),
9917 				       target_size));
9918 		break;
9919 
9920 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
9921 #if IS_ENABLED(CONFIG_IPV6)
9922 		off = si->off;
9923 		off -= offsetof(struct bpf_sock, src_ip6[0]);
9924 		*insn++ = BPF_LDX_MEM(
9925 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9926 			bpf_target_off(
9927 				struct sock_common,
9928 				skc_v6_rcv_saddr.s6_addr32[0],
9929 				sizeof_field(struct sock_common,
9930 					     skc_v6_rcv_saddr.s6_addr32[0]),
9931 				target_size) + off);
9932 #else
9933 		(void)off;
9934 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9935 #endif
9936 		break;
9937 
9938 	case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
9939 #if IS_ENABLED(CONFIG_IPV6)
9940 		off = si->off;
9941 		off -= offsetof(struct bpf_sock, dst_ip6[0]);
9942 		*insn++ = BPF_LDX_MEM(
9943 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9944 			bpf_target_off(struct sock_common,
9945 				       skc_v6_daddr.s6_addr32[0],
9946 				       sizeof_field(struct sock_common,
9947 						    skc_v6_daddr.s6_addr32[0]),
9948 				       target_size) + off);
9949 #else
9950 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9951 		*target_size = 4;
9952 #endif
9953 		break;
9954 
9955 	case offsetof(struct bpf_sock, src_port):
9956 		*insn++ = BPF_LDX_MEM(
9957 			BPF_FIELD_SIZEOF(struct sock_common, skc_num),
9958 			si->dst_reg, si->src_reg,
9959 			bpf_target_off(struct sock_common, skc_num,
9960 				       sizeof_field(struct sock_common,
9961 						    skc_num),
9962 				       target_size));
9963 		break;
9964 
9965 	case offsetof(struct bpf_sock, dst_port):
9966 		*insn++ = BPF_LDX_MEM(
9967 			BPF_FIELD_SIZEOF(struct sock_common, skc_dport),
9968 			si->dst_reg, si->src_reg,
9969 			bpf_target_off(struct sock_common, skc_dport,
9970 				       sizeof_field(struct sock_common,
9971 						    skc_dport),
9972 				       target_size));
9973 		break;
9974 
9975 	case offsetof(struct bpf_sock, state):
9976 		*insn++ = BPF_LDX_MEM(
9977 			BPF_FIELD_SIZEOF(struct sock_common, skc_state),
9978 			si->dst_reg, si->src_reg,
9979 			bpf_target_off(struct sock_common, skc_state,
9980 				       sizeof_field(struct sock_common,
9981 						    skc_state),
9982 				       target_size));
9983 		break;
9984 	case offsetof(struct bpf_sock, rx_queue_mapping):
9985 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
9986 		*insn++ = BPF_LDX_MEM(
9987 			BPF_FIELD_SIZEOF(struct sock, sk_rx_queue_mapping),
9988 			si->dst_reg, si->src_reg,
9989 			bpf_target_off(struct sock, sk_rx_queue_mapping,
9990 				       sizeof_field(struct sock,
9991 						    sk_rx_queue_mapping),
9992 				       target_size));
9993 		*insn++ = BPF_JMP_IMM(BPF_JNE, si->dst_reg, NO_QUEUE_MAPPING,
9994 				      1);
9995 		*insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9996 #else
9997 		*insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9998 		*target_size = 2;
9999 #endif
10000 		break;
10001 	}
10002 
10003 	return insn - insn_buf;
10004 }
10005 
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)10006 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
10007 					 const struct bpf_insn *si,
10008 					 struct bpf_insn *insn_buf,
10009 					 struct bpf_prog *prog, u32 *target_size)
10010 {
10011 	struct bpf_insn *insn = insn_buf;
10012 
10013 	switch (si->off) {
10014 	case offsetof(struct __sk_buff, ifindex):
10015 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
10016 				      si->dst_reg, si->src_reg,
10017 				      offsetof(struct sk_buff, dev));
10018 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10019 				      bpf_target_off(struct net_device, ifindex, 4,
10020 						     target_size));
10021 		break;
10022 	default:
10023 		return bpf_convert_ctx_access(type, si, insn_buf, prog,
10024 					      target_size);
10025 	}
10026 
10027 	return insn - insn_buf;
10028 }
10029 
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)10030 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
10031 				  const struct bpf_insn *si,
10032 				  struct bpf_insn *insn_buf,
10033 				  struct bpf_prog *prog, u32 *target_size)
10034 {
10035 	struct bpf_insn *insn = insn_buf;
10036 
10037 	switch (si->off) {
10038 	case offsetof(struct xdp_md, data):
10039 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
10040 				      si->dst_reg, si->src_reg,
10041 				      offsetof(struct xdp_buff, data));
10042 		break;
10043 	case offsetof(struct xdp_md, data_meta):
10044 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
10045 				      si->dst_reg, si->src_reg,
10046 				      offsetof(struct xdp_buff, data_meta));
10047 		break;
10048 	case offsetof(struct xdp_md, data_end):
10049 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
10050 				      si->dst_reg, si->src_reg,
10051 				      offsetof(struct xdp_buff, data_end));
10052 		break;
10053 	case offsetof(struct xdp_md, ingress_ifindex):
10054 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
10055 				      si->dst_reg, si->src_reg,
10056 				      offsetof(struct xdp_buff, rxq));
10057 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
10058 				      si->dst_reg, si->dst_reg,
10059 				      offsetof(struct xdp_rxq_info, dev));
10060 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10061 				      offsetof(struct net_device, ifindex));
10062 		break;
10063 	case offsetof(struct xdp_md, rx_queue_index):
10064 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
10065 				      si->dst_reg, si->src_reg,
10066 				      offsetof(struct xdp_buff, rxq));
10067 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10068 				      offsetof(struct xdp_rxq_info,
10069 					       queue_index));
10070 		break;
10071 	case offsetof(struct xdp_md, egress_ifindex):
10072 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, txq),
10073 				      si->dst_reg, si->src_reg,
10074 				      offsetof(struct xdp_buff, txq));
10075 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_txq_info, dev),
10076 				      si->dst_reg, si->dst_reg,
10077 				      offsetof(struct xdp_txq_info, dev));
10078 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10079 				      offsetof(struct net_device, ifindex));
10080 		break;
10081 	}
10082 
10083 	return insn - insn_buf;
10084 }
10085 
10086 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
10087  * context Structure, F is Field in context structure that contains a pointer
10088  * to Nested Structure of type NS that has the field NF.
10089  *
10090  * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
10091  * sure that SIZE is not greater than actual size of S.F.NF.
10092  *
10093  * If offset OFF is provided, the load happens from that offset relative to
10094  * offset of NF.
10095  */
10096 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF)	       \
10097 	do {								       \
10098 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg,     \
10099 				      si->src_reg, offsetof(S, F));	       \
10100 		*insn++ = BPF_LDX_MEM(					       \
10101 			SIZE, si->dst_reg, si->dst_reg,			       \
10102 			bpf_target_off(NS, NF, sizeof_field(NS, NF),	       \
10103 				       target_size)			       \
10104 				+ OFF);					       \
10105 	} while (0)
10106 
10107 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF)			       \
10108 	SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF,		       \
10109 					     BPF_FIELD_SIZEOF(NS, NF), 0)
10110 
10111 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
10112  * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
10113  *
10114  * In addition it uses Temporary Field TF (member of struct S) as the 3rd
10115  * "register" since two registers available in convert_ctx_access are not
10116  * enough: we can't override neither SRC, since it contains value to store, nor
10117  * DST since it contains pointer to context that may be used by later
10118  * instructions. But we need a temporary place to save pointer to nested
10119  * structure whose field we want to store to.
10120  */
10121 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, OFF, TF)	       \
10122 	do {								       \
10123 		int tmp_reg = BPF_REG_9;				       \
10124 		if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)	       \
10125 			--tmp_reg;					       \
10126 		if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)	       \
10127 			--tmp_reg;					       \
10128 		*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg,	       \
10129 				      offsetof(S, TF));			       \
10130 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg,	       \
10131 				      si->dst_reg, offsetof(S, F));	       \
10132 		*insn++ = BPF_RAW_INSN(SIZE | BPF_MEM | BPF_CLASS(si->code),   \
10133 				       tmp_reg, si->src_reg,		       \
10134 			bpf_target_off(NS, NF, sizeof_field(NS, NF),	       \
10135 				       target_size)			       \
10136 				       + OFF,				       \
10137 				       si->imm);			       \
10138 		*insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg,	       \
10139 				      offsetof(S, TF));			       \
10140 	} while (0)
10141 
10142 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
10143 						      TF)		       \
10144 	do {								       \
10145 		if (type == BPF_WRITE) {				       \
10146 			SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE,   \
10147 							 OFF, TF);	       \
10148 		} else {						       \
10149 			SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(		       \
10150 				S, NS, F, NF, SIZE, OFF);  \
10151 		}							       \
10152 	} while (0)
10153 
10154 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF)		       \
10155 	SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(			       \
10156 		S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
10157 
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)10158 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
10159 					const struct bpf_insn *si,
10160 					struct bpf_insn *insn_buf,
10161 					struct bpf_prog *prog, u32 *target_size)
10162 {
10163 	int off, port_size = sizeof_field(struct sockaddr_in6, sin6_port);
10164 	struct bpf_insn *insn = insn_buf;
10165 
10166 	switch (si->off) {
10167 	case offsetof(struct bpf_sock_addr, user_family):
10168 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10169 					    struct sockaddr, uaddr, sa_family);
10170 		break;
10171 
10172 	case offsetof(struct bpf_sock_addr, user_ip4):
10173 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10174 			struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
10175 			sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
10176 		break;
10177 
10178 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
10179 		off = si->off;
10180 		off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
10181 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10182 			struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
10183 			sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
10184 			tmp_reg);
10185 		break;
10186 
10187 	case offsetof(struct bpf_sock_addr, user_port):
10188 		/* To get port we need to know sa_family first and then treat
10189 		 * sockaddr as either sockaddr_in or sockaddr_in6.
10190 		 * Though we can simplify since port field has same offset and
10191 		 * size in both structures.
10192 		 * Here we check this invariant and use just one of the
10193 		 * structures if it's true.
10194 		 */
10195 		BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
10196 			     offsetof(struct sockaddr_in6, sin6_port));
10197 		BUILD_BUG_ON(sizeof_field(struct sockaddr_in, sin_port) !=
10198 			     sizeof_field(struct sockaddr_in6, sin6_port));
10199 		/* Account for sin6_port being smaller than user_port. */
10200 		port_size = min(port_size, BPF_LDST_BYTES(si));
10201 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10202 			struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
10203 			sin6_port, bytes_to_bpf_size(port_size), 0, tmp_reg);
10204 		break;
10205 
10206 	case offsetof(struct bpf_sock_addr, family):
10207 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10208 					    struct sock, sk, sk_family);
10209 		break;
10210 
10211 	case offsetof(struct bpf_sock_addr, type):
10212 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10213 					    struct sock, sk, sk_type);
10214 		break;
10215 
10216 	case offsetof(struct bpf_sock_addr, protocol):
10217 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
10218 					    struct sock, sk, sk_protocol);
10219 		break;
10220 
10221 	case offsetof(struct bpf_sock_addr, msg_src_ip4):
10222 		/* Treat t_ctx as struct in_addr for msg_src_ip4. */
10223 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10224 			struct bpf_sock_addr_kern, struct in_addr, t_ctx,
10225 			s_addr, BPF_SIZE(si->code), 0, tmp_reg);
10226 		break;
10227 
10228 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
10229 				msg_src_ip6[3]):
10230 		off = si->off;
10231 		off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
10232 		/* Treat t_ctx as struct in6_addr for msg_src_ip6. */
10233 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
10234 			struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
10235 			s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
10236 		break;
10237 	case offsetof(struct bpf_sock_addr, sk):
10238 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk),
10239 				      si->dst_reg, si->src_reg,
10240 				      offsetof(struct bpf_sock_addr_kern, sk));
10241 		break;
10242 	}
10243 
10244 	return insn - insn_buf;
10245 }
10246 
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)10247 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
10248 				       const struct bpf_insn *si,
10249 				       struct bpf_insn *insn_buf,
10250 				       struct bpf_prog *prog,
10251 				       u32 *target_size)
10252 {
10253 	struct bpf_insn *insn = insn_buf;
10254 	int off;
10255 
10256 /* Helper macro for adding read access to tcp_sock or sock fields. */
10257 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)			      \
10258 	do {								      \
10259 		int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 2;     \
10260 		BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >		      \
10261 			     sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
10262 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10263 			reg--;						      \
10264 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10265 			reg--;						      \
10266 		if (si->dst_reg == si->src_reg) {			      \
10267 			*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,	      \
10268 					  offsetof(struct bpf_sock_ops_kern,  \
10269 					  temp));			      \
10270 			fullsock_reg = reg;				      \
10271 			jmp += 2;					      \
10272 		}							      \
10273 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10274 						struct bpf_sock_ops_kern,     \
10275 						is_fullsock),		      \
10276 				      fullsock_reg, si->src_reg,	      \
10277 				      offsetof(struct bpf_sock_ops_kern,      \
10278 					       is_fullsock));		      \
10279 		*insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);	      \
10280 		if (si->dst_reg == si->src_reg)				      \
10281 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10282 				      offsetof(struct bpf_sock_ops_kern,      \
10283 				      temp));				      \
10284 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10285 						struct bpf_sock_ops_kern, sk),\
10286 				      si->dst_reg, si->src_reg,		      \
10287 				      offsetof(struct bpf_sock_ops_kern, sk));\
10288 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ,		      \
10289 						       OBJ_FIELD),	      \
10290 				      si->dst_reg, si->dst_reg,		      \
10291 				      offsetof(OBJ, OBJ_FIELD));	      \
10292 		if (si->dst_reg == si->src_reg)	{			      \
10293 			*insn++ = BPF_JMP_A(1);				      \
10294 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10295 				      offsetof(struct bpf_sock_ops_kern,      \
10296 				      temp));				      \
10297 		}							      \
10298 	} while (0)
10299 
10300 #define SOCK_OPS_GET_SK()							      \
10301 	do {								      \
10302 		int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 1;     \
10303 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10304 			reg--;						      \
10305 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10306 			reg--;						      \
10307 		if (si->dst_reg == si->src_reg) {			      \
10308 			*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,	      \
10309 					  offsetof(struct bpf_sock_ops_kern,  \
10310 					  temp));			      \
10311 			fullsock_reg = reg;				      \
10312 			jmp += 2;					      \
10313 		}							      \
10314 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10315 						struct bpf_sock_ops_kern,     \
10316 						is_fullsock),		      \
10317 				      fullsock_reg, si->src_reg,	      \
10318 				      offsetof(struct bpf_sock_ops_kern,      \
10319 					       is_fullsock));		      \
10320 		*insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);	      \
10321 		if (si->dst_reg == si->src_reg)				      \
10322 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10323 				      offsetof(struct bpf_sock_ops_kern,      \
10324 				      temp));				      \
10325 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10326 						struct bpf_sock_ops_kern, sk),\
10327 				      si->dst_reg, si->src_reg,		      \
10328 				      offsetof(struct bpf_sock_ops_kern, sk));\
10329 		if (si->dst_reg == si->src_reg)	{			      \
10330 			*insn++ = BPF_JMP_A(1);				      \
10331 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10332 				      offsetof(struct bpf_sock_ops_kern,      \
10333 				      temp));				      \
10334 		}							      \
10335 	} while (0)
10336 
10337 #define SOCK_OPS_GET_TCP_SOCK_FIELD(FIELD) \
10338 		SOCK_OPS_GET_FIELD(FIELD, FIELD, struct tcp_sock)
10339 
10340 /* Helper macro for adding write access to tcp_sock or sock fields.
10341  * The macro is called with two registers, dst_reg which contains a pointer
10342  * to ctx (context) and src_reg which contains the value that should be
10343  * stored. However, we need an additional register since we cannot overwrite
10344  * dst_reg because it may be used later in the program.
10345  * Instead we "borrow" one of the other register. We first save its value
10346  * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
10347  * it at the end of the macro.
10348  */
10349 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)			      \
10350 	do {								      \
10351 		int reg = BPF_REG_9;					      \
10352 		BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >		      \
10353 			     sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
10354 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10355 			reg--;						      \
10356 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10357 			reg--;						      \
10358 		*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg,		      \
10359 				      offsetof(struct bpf_sock_ops_kern,      \
10360 					       temp));			      \
10361 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10362 						struct bpf_sock_ops_kern,     \
10363 						is_fullsock),		      \
10364 				      reg, si->dst_reg,			      \
10365 				      offsetof(struct bpf_sock_ops_kern,      \
10366 					       is_fullsock));		      \
10367 		*insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2);		      \
10368 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10369 						struct bpf_sock_ops_kern, sk),\
10370 				      reg, si->dst_reg,			      \
10371 				      offsetof(struct bpf_sock_ops_kern, sk));\
10372 		*insn++ = BPF_RAW_INSN(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD) |     \
10373 				       BPF_MEM | BPF_CLASS(si->code),	      \
10374 				       reg, si->src_reg,		      \
10375 				       offsetof(OBJ, OBJ_FIELD),	      \
10376 				       si->imm);			      \
10377 		*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg,		      \
10378 				      offsetof(struct bpf_sock_ops_kern,      \
10379 					       temp));			      \
10380 	} while (0)
10381 
10382 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE)	      \
10383 	do {								      \
10384 		if (TYPE == BPF_WRITE)					      \
10385 			SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
10386 		else							      \
10387 			SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
10388 	} while (0)
10389 
10390 	switch (si->off) {
10391 	case offsetof(struct bpf_sock_ops, op):
10392 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10393 						       op),
10394 				      si->dst_reg, si->src_reg,
10395 				      offsetof(struct bpf_sock_ops_kern, op));
10396 		break;
10397 
10398 	case offsetof(struct bpf_sock_ops, replylong[0]) ...
10399 	     offsetof(struct bpf_sock_ops, replylong[3]):
10400 		BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, reply) !=
10401 			     sizeof_field(struct bpf_sock_ops_kern, reply));
10402 		BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, replylong) !=
10403 			     sizeof_field(struct bpf_sock_ops_kern, replylong));
10404 		off = si->off;
10405 		off -= offsetof(struct bpf_sock_ops, replylong[0]);
10406 		off += offsetof(struct bpf_sock_ops_kern, replylong[0]);
10407 		if (type == BPF_WRITE)
10408 			*insn++ = BPF_EMIT_STORE(BPF_W, si, off);
10409 		else
10410 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
10411 					      off);
10412 		break;
10413 
10414 	case offsetof(struct bpf_sock_ops, family):
10415 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
10416 
10417 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10418 					      struct bpf_sock_ops_kern, sk),
10419 				      si->dst_reg, si->src_reg,
10420 				      offsetof(struct bpf_sock_ops_kern, sk));
10421 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10422 				      offsetof(struct sock_common, skc_family));
10423 		break;
10424 
10425 	case offsetof(struct bpf_sock_ops, remote_ip4):
10426 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10427 
10428 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10429 						struct bpf_sock_ops_kern, sk),
10430 				      si->dst_reg, si->src_reg,
10431 				      offsetof(struct bpf_sock_ops_kern, sk));
10432 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10433 				      offsetof(struct sock_common, skc_daddr));
10434 		break;
10435 
10436 	case offsetof(struct bpf_sock_ops, local_ip4):
10437 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10438 					  skc_rcv_saddr) != 4);
10439 
10440 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10441 					      struct bpf_sock_ops_kern, sk),
10442 				      si->dst_reg, si->src_reg,
10443 				      offsetof(struct bpf_sock_ops_kern, sk));
10444 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10445 				      offsetof(struct sock_common,
10446 					       skc_rcv_saddr));
10447 		break;
10448 
10449 	case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
10450 	     offsetof(struct bpf_sock_ops, remote_ip6[3]):
10451 #if IS_ENABLED(CONFIG_IPV6)
10452 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10453 					  skc_v6_daddr.s6_addr32[0]) != 4);
10454 
10455 		off = si->off;
10456 		off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
10457 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10458 						struct bpf_sock_ops_kern, sk),
10459 				      si->dst_reg, si->src_reg,
10460 				      offsetof(struct bpf_sock_ops_kern, sk));
10461 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10462 				      offsetof(struct sock_common,
10463 					       skc_v6_daddr.s6_addr32[0]) +
10464 				      off);
10465 #else
10466 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10467 #endif
10468 		break;
10469 
10470 	case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
10471 	     offsetof(struct bpf_sock_ops, local_ip6[3]):
10472 #if IS_ENABLED(CONFIG_IPV6)
10473 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10474 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10475 
10476 		off = si->off;
10477 		off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
10478 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10479 						struct bpf_sock_ops_kern, sk),
10480 				      si->dst_reg, si->src_reg,
10481 				      offsetof(struct bpf_sock_ops_kern, sk));
10482 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10483 				      offsetof(struct sock_common,
10484 					       skc_v6_rcv_saddr.s6_addr32[0]) +
10485 				      off);
10486 #else
10487 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10488 #endif
10489 		break;
10490 
10491 	case offsetof(struct bpf_sock_ops, remote_port):
10492 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10493 
10494 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10495 						struct bpf_sock_ops_kern, sk),
10496 				      si->dst_reg, si->src_reg,
10497 				      offsetof(struct bpf_sock_ops_kern, sk));
10498 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10499 				      offsetof(struct sock_common, skc_dport));
10500 #ifndef __BIG_ENDIAN_BITFIELD
10501 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10502 #endif
10503 		break;
10504 
10505 	case offsetof(struct bpf_sock_ops, local_port):
10506 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10507 
10508 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10509 						struct bpf_sock_ops_kern, sk),
10510 				      si->dst_reg, si->src_reg,
10511 				      offsetof(struct bpf_sock_ops_kern, sk));
10512 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10513 				      offsetof(struct sock_common, skc_num));
10514 		break;
10515 
10516 	case offsetof(struct bpf_sock_ops, is_fullsock):
10517 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10518 						struct bpf_sock_ops_kern,
10519 						is_fullsock),
10520 				      si->dst_reg, si->src_reg,
10521 				      offsetof(struct bpf_sock_ops_kern,
10522 					       is_fullsock));
10523 		break;
10524 
10525 	case offsetof(struct bpf_sock_ops, state):
10526 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_state) != 1);
10527 
10528 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10529 						struct bpf_sock_ops_kern, sk),
10530 				      si->dst_reg, si->src_reg,
10531 				      offsetof(struct bpf_sock_ops_kern, sk));
10532 		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
10533 				      offsetof(struct sock_common, skc_state));
10534 		break;
10535 
10536 	case offsetof(struct bpf_sock_ops, rtt_min):
10537 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
10538 			     sizeof(struct minmax));
10539 		BUILD_BUG_ON(sizeof(struct minmax) <
10540 			     sizeof(struct minmax_sample));
10541 
10542 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10543 						struct bpf_sock_ops_kern, sk),
10544 				      si->dst_reg, si->src_reg,
10545 				      offsetof(struct bpf_sock_ops_kern, sk));
10546 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10547 				      offsetof(struct tcp_sock, rtt_min) +
10548 				      sizeof_field(struct minmax_sample, t));
10549 		break;
10550 
10551 	case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
10552 		SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
10553 				   struct tcp_sock);
10554 		break;
10555 
10556 	case offsetof(struct bpf_sock_ops, sk_txhash):
10557 		SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
10558 					  struct sock, type);
10559 		break;
10560 	case offsetof(struct bpf_sock_ops, snd_cwnd):
10561 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_cwnd);
10562 		break;
10563 	case offsetof(struct bpf_sock_ops, srtt_us):
10564 		SOCK_OPS_GET_TCP_SOCK_FIELD(srtt_us);
10565 		break;
10566 	case offsetof(struct bpf_sock_ops, snd_ssthresh):
10567 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_ssthresh);
10568 		break;
10569 	case offsetof(struct bpf_sock_ops, rcv_nxt):
10570 		SOCK_OPS_GET_TCP_SOCK_FIELD(rcv_nxt);
10571 		break;
10572 	case offsetof(struct bpf_sock_ops, snd_nxt):
10573 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_nxt);
10574 		break;
10575 	case offsetof(struct bpf_sock_ops, snd_una):
10576 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_una);
10577 		break;
10578 	case offsetof(struct bpf_sock_ops, mss_cache):
10579 		SOCK_OPS_GET_TCP_SOCK_FIELD(mss_cache);
10580 		break;
10581 	case offsetof(struct bpf_sock_ops, ecn_flags):
10582 		SOCK_OPS_GET_TCP_SOCK_FIELD(ecn_flags);
10583 		break;
10584 	case offsetof(struct bpf_sock_ops, rate_delivered):
10585 		SOCK_OPS_GET_TCP_SOCK_FIELD(rate_delivered);
10586 		break;
10587 	case offsetof(struct bpf_sock_ops, rate_interval_us):
10588 		SOCK_OPS_GET_TCP_SOCK_FIELD(rate_interval_us);
10589 		break;
10590 	case offsetof(struct bpf_sock_ops, packets_out):
10591 		SOCK_OPS_GET_TCP_SOCK_FIELD(packets_out);
10592 		break;
10593 	case offsetof(struct bpf_sock_ops, retrans_out):
10594 		SOCK_OPS_GET_TCP_SOCK_FIELD(retrans_out);
10595 		break;
10596 	case offsetof(struct bpf_sock_ops, total_retrans):
10597 		SOCK_OPS_GET_TCP_SOCK_FIELD(total_retrans);
10598 		break;
10599 	case offsetof(struct bpf_sock_ops, segs_in):
10600 		SOCK_OPS_GET_TCP_SOCK_FIELD(segs_in);
10601 		break;
10602 	case offsetof(struct bpf_sock_ops, data_segs_in):
10603 		SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_in);
10604 		break;
10605 	case offsetof(struct bpf_sock_ops, segs_out):
10606 		SOCK_OPS_GET_TCP_SOCK_FIELD(segs_out);
10607 		break;
10608 	case offsetof(struct bpf_sock_ops, data_segs_out):
10609 		SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_out);
10610 		break;
10611 	case offsetof(struct bpf_sock_ops, lost_out):
10612 		SOCK_OPS_GET_TCP_SOCK_FIELD(lost_out);
10613 		break;
10614 	case offsetof(struct bpf_sock_ops, sacked_out):
10615 		SOCK_OPS_GET_TCP_SOCK_FIELD(sacked_out);
10616 		break;
10617 	case offsetof(struct bpf_sock_ops, bytes_received):
10618 		SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_received);
10619 		break;
10620 	case offsetof(struct bpf_sock_ops, bytes_acked):
10621 		SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_acked);
10622 		break;
10623 	case offsetof(struct bpf_sock_ops, sk):
10624 		SOCK_OPS_GET_SK();
10625 		break;
10626 	case offsetof(struct bpf_sock_ops, skb_data_end):
10627 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10628 						       skb_data_end),
10629 				      si->dst_reg, si->src_reg,
10630 				      offsetof(struct bpf_sock_ops_kern,
10631 					       skb_data_end));
10632 		break;
10633 	case offsetof(struct bpf_sock_ops, skb_data):
10634 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10635 						       skb),
10636 				      si->dst_reg, si->src_reg,
10637 				      offsetof(struct bpf_sock_ops_kern,
10638 					       skb));
10639 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10640 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10641 				      si->dst_reg, si->dst_reg,
10642 				      offsetof(struct sk_buff, data));
10643 		break;
10644 	case offsetof(struct bpf_sock_ops, skb_len):
10645 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10646 						       skb),
10647 				      si->dst_reg, si->src_reg,
10648 				      offsetof(struct bpf_sock_ops_kern,
10649 					       skb));
10650 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10651 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10652 				      si->dst_reg, si->dst_reg,
10653 				      offsetof(struct sk_buff, len));
10654 		break;
10655 	case offsetof(struct bpf_sock_ops, skb_tcp_flags):
10656 		off = offsetof(struct sk_buff, cb);
10657 		off += offsetof(struct tcp_skb_cb, tcp_flags);
10658 		*target_size = sizeof_field(struct tcp_skb_cb, tcp_flags);
10659 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10660 						       skb),
10661 				      si->dst_reg, si->src_reg,
10662 				      offsetof(struct bpf_sock_ops_kern,
10663 					       skb));
10664 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10665 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_skb_cb,
10666 						       tcp_flags),
10667 				      si->dst_reg, si->dst_reg, off);
10668 		break;
10669 	case offsetof(struct bpf_sock_ops, skb_hwtstamp): {
10670 		struct bpf_insn *jmp_on_null_skb;
10671 
10672 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10673 						       skb),
10674 				      si->dst_reg, si->src_reg,
10675 				      offsetof(struct bpf_sock_ops_kern,
10676 					       skb));
10677 		/* Reserve one insn to test skb == NULL */
10678 		jmp_on_null_skb = insn++;
10679 		insn = bpf_convert_shinfo_access(si->dst_reg, si->dst_reg, insn);
10680 		*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
10681 				      bpf_target_off(struct skb_shared_info,
10682 						     hwtstamps, 8,
10683 						     target_size));
10684 		*jmp_on_null_skb = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0,
10685 					       insn - jmp_on_null_skb - 1);
10686 		break;
10687 	}
10688 	}
10689 	return insn - insn_buf;
10690 }
10691 
10692 /* data_end = skb->data + skb_headlen() */
bpf_convert_data_end_access(const struct bpf_insn * si,struct bpf_insn * insn)10693 static struct bpf_insn *bpf_convert_data_end_access(const struct bpf_insn *si,
10694 						    struct bpf_insn *insn)
10695 {
10696 	int reg;
10697 	int temp_reg_off = offsetof(struct sk_buff, cb) +
10698 			   offsetof(struct sk_skb_cb, temp_reg);
10699 
10700 	if (si->src_reg == si->dst_reg) {
10701 		/* We need an extra register, choose and save a register. */
10702 		reg = BPF_REG_9;
10703 		if (si->src_reg == reg || si->dst_reg == reg)
10704 			reg--;
10705 		if (si->src_reg == reg || si->dst_reg == reg)
10706 			reg--;
10707 		*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, temp_reg_off);
10708 	} else {
10709 		reg = si->dst_reg;
10710 	}
10711 
10712 	/* reg = skb->data */
10713 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10714 			      reg, si->src_reg,
10715 			      offsetof(struct sk_buff, data));
10716 	/* AX = skb->len */
10717 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10718 			      BPF_REG_AX, si->src_reg,
10719 			      offsetof(struct sk_buff, len));
10720 	/* reg = skb->data + skb->len */
10721 	*insn++ = BPF_ALU64_REG(BPF_ADD, reg, BPF_REG_AX);
10722 	/* AX = skb->data_len */
10723 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data_len),
10724 			      BPF_REG_AX, si->src_reg,
10725 			      offsetof(struct sk_buff, data_len));
10726 
10727 	/* reg = skb->data + skb->len - skb->data_len */
10728 	*insn++ = BPF_ALU64_REG(BPF_SUB, reg, BPF_REG_AX);
10729 
10730 	if (si->src_reg == si->dst_reg) {
10731 		/* Restore the saved register */
10732 		*insn++ = BPF_MOV64_REG(BPF_REG_AX, si->src_reg);
10733 		*insn++ = BPF_MOV64_REG(si->dst_reg, reg);
10734 		*insn++ = BPF_LDX_MEM(BPF_DW, reg, BPF_REG_AX, temp_reg_off);
10735 	}
10736 
10737 	return insn;
10738 }
10739 
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)10740 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
10741 				     const struct bpf_insn *si,
10742 				     struct bpf_insn *insn_buf,
10743 				     struct bpf_prog *prog, u32 *target_size)
10744 {
10745 	struct bpf_insn *insn = insn_buf;
10746 	int off;
10747 
10748 	switch (si->off) {
10749 	case offsetof(struct __sk_buff, data_end):
10750 		insn = bpf_convert_data_end_access(si, insn);
10751 		break;
10752 	case offsetof(struct __sk_buff, cb[0]) ...
10753 	     offsetofend(struct __sk_buff, cb[4]) - 1:
10754 		BUILD_BUG_ON(sizeof_field(struct sk_skb_cb, data) < 20);
10755 		BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
10756 			      offsetof(struct sk_skb_cb, data)) %
10757 			     sizeof(__u64));
10758 
10759 		prog->cb_access = 1;
10760 		off  = si->off;
10761 		off -= offsetof(struct __sk_buff, cb[0]);
10762 		off += offsetof(struct sk_buff, cb);
10763 		off += offsetof(struct sk_skb_cb, data);
10764 		if (type == BPF_WRITE)
10765 			*insn++ = BPF_EMIT_STORE(BPF_SIZE(si->code), si, off);
10766 		else
10767 			*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
10768 					      si->src_reg, off);
10769 		break;
10770 
10771 
10772 	default:
10773 		return bpf_convert_ctx_access(type, si, insn_buf, prog,
10774 					      target_size);
10775 	}
10776 
10777 	return insn - insn_buf;
10778 }
10779 
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)10780 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
10781 				     const struct bpf_insn *si,
10782 				     struct bpf_insn *insn_buf,
10783 				     struct bpf_prog *prog, u32 *target_size)
10784 {
10785 	struct bpf_insn *insn = insn_buf;
10786 #if IS_ENABLED(CONFIG_IPV6)
10787 	int off;
10788 #endif
10789 
10790 	/* convert ctx uses the fact sg element is first in struct */
10791 	BUILD_BUG_ON(offsetof(struct sk_msg, sg) != 0);
10792 
10793 	switch (si->off) {
10794 	case offsetof(struct sk_msg_md, data):
10795 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data),
10796 				      si->dst_reg, si->src_reg,
10797 				      offsetof(struct sk_msg, data));
10798 		break;
10799 	case offsetof(struct sk_msg_md, data_end):
10800 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end),
10801 				      si->dst_reg, si->src_reg,
10802 				      offsetof(struct sk_msg, data_end));
10803 		break;
10804 	case offsetof(struct sk_msg_md, family):
10805 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
10806 
10807 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10808 					      struct sk_msg, sk),
10809 				      si->dst_reg, si->src_reg,
10810 				      offsetof(struct sk_msg, sk));
10811 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10812 				      offsetof(struct sock_common, skc_family));
10813 		break;
10814 
10815 	case offsetof(struct sk_msg_md, remote_ip4):
10816 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10817 
10818 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10819 						struct sk_msg, sk),
10820 				      si->dst_reg, si->src_reg,
10821 				      offsetof(struct sk_msg, sk));
10822 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10823 				      offsetof(struct sock_common, skc_daddr));
10824 		break;
10825 
10826 	case offsetof(struct sk_msg_md, local_ip4):
10827 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10828 					  skc_rcv_saddr) != 4);
10829 
10830 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10831 					      struct sk_msg, sk),
10832 				      si->dst_reg, si->src_reg,
10833 				      offsetof(struct sk_msg, sk));
10834 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10835 				      offsetof(struct sock_common,
10836 					       skc_rcv_saddr));
10837 		break;
10838 
10839 	case offsetof(struct sk_msg_md, remote_ip6[0]) ...
10840 	     offsetof(struct sk_msg_md, remote_ip6[3]):
10841 #if IS_ENABLED(CONFIG_IPV6)
10842 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10843 					  skc_v6_daddr.s6_addr32[0]) != 4);
10844 
10845 		off = si->off;
10846 		off -= offsetof(struct sk_msg_md, remote_ip6[0]);
10847 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10848 						struct sk_msg, sk),
10849 				      si->dst_reg, si->src_reg,
10850 				      offsetof(struct sk_msg, sk));
10851 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10852 				      offsetof(struct sock_common,
10853 					       skc_v6_daddr.s6_addr32[0]) +
10854 				      off);
10855 #else
10856 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10857 #endif
10858 		break;
10859 
10860 	case offsetof(struct sk_msg_md, local_ip6[0]) ...
10861 	     offsetof(struct sk_msg_md, local_ip6[3]):
10862 #if IS_ENABLED(CONFIG_IPV6)
10863 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10864 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10865 
10866 		off = si->off;
10867 		off -= offsetof(struct sk_msg_md, local_ip6[0]);
10868 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10869 						struct sk_msg, sk),
10870 				      si->dst_reg, si->src_reg,
10871 				      offsetof(struct sk_msg, sk));
10872 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10873 				      offsetof(struct sock_common,
10874 					       skc_v6_rcv_saddr.s6_addr32[0]) +
10875 				      off);
10876 #else
10877 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10878 #endif
10879 		break;
10880 
10881 	case offsetof(struct sk_msg_md, remote_port):
10882 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10883 
10884 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10885 						struct sk_msg, sk),
10886 				      si->dst_reg, si->src_reg,
10887 				      offsetof(struct sk_msg, sk));
10888 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10889 				      offsetof(struct sock_common, skc_dport));
10890 #ifndef __BIG_ENDIAN_BITFIELD
10891 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10892 #endif
10893 		break;
10894 
10895 	case offsetof(struct sk_msg_md, local_port):
10896 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10897 
10898 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10899 						struct sk_msg, sk),
10900 				      si->dst_reg, si->src_reg,
10901 				      offsetof(struct sk_msg, sk));
10902 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10903 				      offsetof(struct sock_common, skc_num));
10904 		break;
10905 
10906 	case offsetof(struct sk_msg_md, size):
10907 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
10908 				      si->dst_reg, si->src_reg,
10909 				      offsetof(struct sk_msg_sg, size));
10910 		break;
10911 
10912 	case offsetof(struct sk_msg_md, sk):
10913 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, sk),
10914 				      si->dst_reg, si->src_reg,
10915 				      offsetof(struct sk_msg, sk));
10916 		break;
10917 	}
10918 
10919 	return insn - insn_buf;
10920 }
10921 
10922 const struct bpf_verifier_ops sk_filter_verifier_ops = {
10923 	.get_func_proto		= sk_filter_func_proto,
10924 	.is_valid_access	= sk_filter_is_valid_access,
10925 	.convert_ctx_access	= bpf_convert_ctx_access,
10926 	.gen_ld_abs		= bpf_gen_ld_abs,
10927 };
10928 
10929 const struct bpf_prog_ops sk_filter_prog_ops = {
10930 	.test_run		= bpf_prog_test_run_skb,
10931 };
10932 
10933 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
10934 	.get_func_proto		= tc_cls_act_func_proto,
10935 	.is_valid_access	= tc_cls_act_is_valid_access,
10936 	.convert_ctx_access	= tc_cls_act_convert_ctx_access,
10937 	.gen_prologue		= tc_cls_act_prologue,
10938 	.gen_ld_abs		= bpf_gen_ld_abs,
10939 	.btf_struct_access	= tc_cls_act_btf_struct_access,
10940 };
10941 
10942 const struct bpf_prog_ops tc_cls_act_prog_ops = {
10943 	.test_run		= bpf_prog_test_run_skb,
10944 };
10945 
10946 const struct bpf_verifier_ops xdp_verifier_ops = {
10947 	.get_func_proto		= xdp_func_proto,
10948 	.is_valid_access	= xdp_is_valid_access,
10949 	.convert_ctx_access	= xdp_convert_ctx_access,
10950 	.gen_prologue		= bpf_noop_prologue,
10951 	.btf_struct_access	= xdp_btf_struct_access,
10952 };
10953 
10954 const struct bpf_prog_ops xdp_prog_ops = {
10955 	.test_run		= bpf_prog_test_run_xdp,
10956 };
10957 
10958 const struct bpf_verifier_ops cg_skb_verifier_ops = {
10959 	.get_func_proto		= cg_skb_func_proto,
10960 	.is_valid_access	= cg_skb_is_valid_access,
10961 	.convert_ctx_access	= bpf_convert_ctx_access,
10962 };
10963 
10964 const struct bpf_prog_ops cg_skb_prog_ops = {
10965 	.test_run		= bpf_prog_test_run_skb,
10966 };
10967 
10968 const struct bpf_verifier_ops lwt_in_verifier_ops = {
10969 	.get_func_proto		= lwt_in_func_proto,
10970 	.is_valid_access	= lwt_is_valid_access,
10971 	.convert_ctx_access	= bpf_convert_ctx_access,
10972 };
10973 
10974 const struct bpf_prog_ops lwt_in_prog_ops = {
10975 	.test_run		= bpf_prog_test_run_skb,
10976 };
10977 
10978 const struct bpf_verifier_ops lwt_out_verifier_ops = {
10979 	.get_func_proto		= lwt_out_func_proto,
10980 	.is_valid_access	= lwt_is_valid_access,
10981 	.convert_ctx_access	= bpf_convert_ctx_access,
10982 };
10983 
10984 const struct bpf_prog_ops lwt_out_prog_ops = {
10985 	.test_run		= bpf_prog_test_run_skb,
10986 };
10987 
10988 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
10989 	.get_func_proto		= lwt_xmit_func_proto,
10990 	.is_valid_access	= lwt_is_valid_access,
10991 	.convert_ctx_access	= bpf_convert_ctx_access,
10992 	.gen_prologue		= tc_cls_act_prologue,
10993 };
10994 
10995 const struct bpf_prog_ops lwt_xmit_prog_ops = {
10996 	.test_run		= bpf_prog_test_run_skb,
10997 };
10998 
10999 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
11000 	.get_func_proto		= lwt_seg6local_func_proto,
11001 	.is_valid_access	= lwt_is_valid_access,
11002 	.convert_ctx_access	= bpf_convert_ctx_access,
11003 };
11004 
11005 const struct bpf_prog_ops lwt_seg6local_prog_ops = {
11006 	.test_run		= bpf_prog_test_run_skb,
11007 };
11008 
11009 const struct bpf_verifier_ops cg_sock_verifier_ops = {
11010 	.get_func_proto		= sock_filter_func_proto,
11011 	.is_valid_access	= sock_filter_is_valid_access,
11012 	.convert_ctx_access	= bpf_sock_convert_ctx_access,
11013 };
11014 
11015 const struct bpf_prog_ops cg_sock_prog_ops = {
11016 };
11017 
11018 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
11019 	.get_func_proto		= sock_addr_func_proto,
11020 	.is_valid_access	= sock_addr_is_valid_access,
11021 	.convert_ctx_access	= sock_addr_convert_ctx_access,
11022 };
11023 
11024 const struct bpf_prog_ops cg_sock_addr_prog_ops = {
11025 };
11026 
11027 const struct bpf_verifier_ops sock_ops_verifier_ops = {
11028 	.get_func_proto		= sock_ops_func_proto,
11029 	.is_valid_access	= sock_ops_is_valid_access,
11030 	.convert_ctx_access	= sock_ops_convert_ctx_access,
11031 };
11032 
11033 const struct bpf_prog_ops sock_ops_prog_ops = {
11034 };
11035 
11036 const struct bpf_verifier_ops sk_skb_verifier_ops = {
11037 	.get_func_proto		= sk_skb_func_proto,
11038 	.is_valid_access	= sk_skb_is_valid_access,
11039 	.convert_ctx_access	= sk_skb_convert_ctx_access,
11040 	.gen_prologue		= sk_skb_prologue,
11041 };
11042 
11043 const struct bpf_prog_ops sk_skb_prog_ops = {
11044 };
11045 
11046 const struct bpf_verifier_ops sk_msg_verifier_ops = {
11047 	.get_func_proto		= sk_msg_func_proto,
11048 	.is_valid_access	= sk_msg_is_valid_access,
11049 	.convert_ctx_access	= sk_msg_convert_ctx_access,
11050 	.gen_prologue		= bpf_noop_prologue,
11051 };
11052 
11053 const struct bpf_prog_ops sk_msg_prog_ops = {
11054 };
11055 
11056 const struct bpf_verifier_ops flow_dissector_verifier_ops = {
11057 	.get_func_proto		= flow_dissector_func_proto,
11058 	.is_valid_access	= flow_dissector_is_valid_access,
11059 	.convert_ctx_access	= flow_dissector_convert_ctx_access,
11060 };
11061 
11062 const struct bpf_prog_ops flow_dissector_prog_ops = {
11063 	.test_run		= bpf_prog_test_run_flow_dissector,
11064 };
11065 
sk_detach_filter(struct sock * sk)11066 int sk_detach_filter(struct sock *sk)
11067 {
11068 	int ret = -ENOENT;
11069 	struct sk_filter *filter;
11070 
11071 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
11072 		return -EPERM;
11073 
11074 	filter = rcu_dereference_protected(sk->sk_filter,
11075 					   lockdep_sock_is_held(sk));
11076 	if (filter) {
11077 		RCU_INIT_POINTER(sk->sk_filter, NULL);
11078 		sk_filter_uncharge(sk, filter);
11079 		ret = 0;
11080 	}
11081 
11082 	return ret;
11083 }
11084 EXPORT_SYMBOL_GPL(sk_detach_filter);
11085 
sk_get_filter(struct sock * sk,sockptr_t optval,unsigned int len)11086 int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len)
11087 {
11088 	struct sock_fprog_kern *fprog;
11089 	struct sk_filter *filter;
11090 	int ret = 0;
11091 
11092 	sockopt_lock_sock(sk);
11093 	filter = rcu_dereference_protected(sk->sk_filter,
11094 					   lockdep_sock_is_held(sk));
11095 	if (!filter)
11096 		goto out;
11097 
11098 	/* We're copying the filter that has been originally attached,
11099 	 * so no conversion/decode needed anymore. eBPF programs that
11100 	 * have no original program cannot be dumped through this.
11101 	 */
11102 	ret = -EACCES;
11103 	fprog = filter->prog->orig_prog;
11104 	if (!fprog)
11105 		goto out;
11106 
11107 	ret = fprog->len;
11108 	if (!len)
11109 		/* User space only enquires number of filter blocks. */
11110 		goto out;
11111 
11112 	ret = -EINVAL;
11113 	if (len < fprog->len)
11114 		goto out;
11115 
11116 	ret = -EFAULT;
11117 	if (copy_to_sockptr(optval, fprog->filter, bpf_classic_proglen(fprog)))
11118 		goto out;
11119 
11120 	/* Instead of bytes, the API requests to return the number
11121 	 * of filter blocks.
11122 	 */
11123 	ret = fprog->len;
11124 out:
11125 	sockopt_release_sock(sk);
11126 	return ret;
11127 }
11128 
11129 #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)11130 static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
11131 				    struct sock_reuseport *reuse,
11132 				    struct sock *sk, struct sk_buff *skb,
11133 				    struct sock *migrating_sk,
11134 				    u32 hash)
11135 {
11136 	reuse_kern->skb = skb;
11137 	reuse_kern->sk = sk;
11138 	reuse_kern->selected_sk = NULL;
11139 	reuse_kern->migrating_sk = migrating_sk;
11140 	reuse_kern->data_end = skb->data + skb_headlen(skb);
11141 	reuse_kern->hash = hash;
11142 	reuse_kern->reuseport_id = reuse->reuseport_id;
11143 	reuse_kern->bind_inany = reuse->bind_inany;
11144 }
11145 
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)11146 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
11147 				  struct bpf_prog *prog, struct sk_buff *skb,
11148 				  struct sock *migrating_sk,
11149 				  u32 hash)
11150 {
11151 	struct sk_reuseport_kern reuse_kern;
11152 	enum sk_action action;
11153 
11154 	bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, migrating_sk, hash);
11155 	action = bpf_prog_run(prog, &reuse_kern);
11156 
11157 	if (action == SK_PASS)
11158 		return reuse_kern.selected_sk;
11159 	else
11160 		return ERR_PTR(-ECONNREFUSED);
11161 }
11162 
BPF_CALL_4(sk_select_reuseport,struct sk_reuseport_kern *,reuse_kern,struct bpf_map *,map,void *,key,u32,flags)11163 BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
11164 	   struct bpf_map *, map, void *, key, u32, flags)
11165 {
11166 	bool is_sockarray = map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY;
11167 	struct sock_reuseport *reuse;
11168 	struct sock *selected_sk;
11169 
11170 	selected_sk = map->ops->map_lookup_elem(map, key);
11171 	if (!selected_sk)
11172 		return -ENOENT;
11173 
11174 	reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
11175 	if (!reuse) {
11176 		/* Lookup in sock_map can return TCP ESTABLISHED sockets. */
11177 		if (sk_is_refcounted(selected_sk))
11178 			sock_put(selected_sk);
11179 
11180 		/* reuseport_array has only sk with non NULL sk_reuseport_cb.
11181 		 * The only (!reuse) case here is - the sk has already been
11182 		 * unhashed (e.g. by close()), so treat it as -ENOENT.
11183 		 *
11184 		 * Other maps (e.g. sock_map) do not provide this guarantee and
11185 		 * the sk may never be in the reuseport group to begin with.
11186 		 */
11187 		return is_sockarray ? -ENOENT : -EINVAL;
11188 	}
11189 
11190 	if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
11191 		struct sock *sk = reuse_kern->sk;
11192 
11193 		if (sk->sk_protocol != selected_sk->sk_protocol)
11194 			return -EPROTOTYPE;
11195 		else if (sk->sk_family != selected_sk->sk_family)
11196 			return -EAFNOSUPPORT;
11197 
11198 		/* Catch all. Likely bound to a different sockaddr. */
11199 		return -EBADFD;
11200 	}
11201 
11202 	reuse_kern->selected_sk = selected_sk;
11203 
11204 	return 0;
11205 }
11206 
11207 static const struct bpf_func_proto sk_select_reuseport_proto = {
11208 	.func           = sk_select_reuseport,
11209 	.gpl_only       = false,
11210 	.ret_type       = RET_INTEGER,
11211 	.arg1_type	= ARG_PTR_TO_CTX,
11212 	.arg2_type      = ARG_CONST_MAP_PTR,
11213 	.arg3_type      = ARG_PTR_TO_MAP_KEY,
11214 	.arg4_type	= ARG_ANYTHING,
11215 };
11216 
BPF_CALL_4(sk_reuseport_load_bytes,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len)11217 BPF_CALL_4(sk_reuseport_load_bytes,
11218 	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
11219 	   void *, to, u32, len)
11220 {
11221 	return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
11222 }
11223 
11224 static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
11225 	.func		= sk_reuseport_load_bytes,
11226 	.gpl_only	= false,
11227 	.ret_type	= RET_INTEGER,
11228 	.arg1_type	= ARG_PTR_TO_CTX,
11229 	.arg2_type	= ARG_ANYTHING,
11230 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
11231 	.arg4_type	= ARG_CONST_SIZE,
11232 };
11233 
BPF_CALL_5(sk_reuseport_load_bytes_relative,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len,u32,start_header)11234 BPF_CALL_5(sk_reuseport_load_bytes_relative,
11235 	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
11236 	   void *, to, u32, len, u32, start_header)
11237 {
11238 	return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
11239 					       len, start_header);
11240 }
11241 
11242 static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
11243 	.func		= sk_reuseport_load_bytes_relative,
11244 	.gpl_only	= false,
11245 	.ret_type	= RET_INTEGER,
11246 	.arg1_type	= ARG_PTR_TO_CTX,
11247 	.arg2_type	= ARG_ANYTHING,
11248 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
11249 	.arg4_type	= ARG_CONST_SIZE,
11250 	.arg5_type	= ARG_ANYTHING,
11251 };
11252 
11253 static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)11254 sk_reuseport_func_proto(enum bpf_func_id func_id,
11255 			const struct bpf_prog *prog)
11256 {
11257 	switch (func_id) {
11258 	case BPF_FUNC_sk_select_reuseport:
11259 		return &sk_select_reuseport_proto;
11260 	case BPF_FUNC_skb_load_bytes:
11261 		return &sk_reuseport_load_bytes_proto;
11262 	case BPF_FUNC_skb_load_bytes_relative:
11263 		return &sk_reuseport_load_bytes_relative_proto;
11264 	case BPF_FUNC_get_socket_cookie:
11265 		return &bpf_get_socket_ptr_cookie_proto;
11266 	case BPF_FUNC_ktime_get_coarse_ns:
11267 		return &bpf_ktime_get_coarse_ns_proto;
11268 	default:
11269 		return bpf_base_func_proto(func_id);
11270 	}
11271 }
11272 
11273 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)11274 sk_reuseport_is_valid_access(int off, int size,
11275 			     enum bpf_access_type type,
11276 			     const struct bpf_prog *prog,
11277 			     struct bpf_insn_access_aux *info)
11278 {
11279 	const u32 size_default = sizeof(__u32);
11280 
11281 	if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
11282 	    off % size || type != BPF_READ)
11283 		return false;
11284 
11285 	switch (off) {
11286 	case offsetof(struct sk_reuseport_md, data):
11287 		info->reg_type = PTR_TO_PACKET;
11288 		return size == sizeof(__u64);
11289 
11290 	case offsetof(struct sk_reuseport_md, data_end):
11291 		info->reg_type = PTR_TO_PACKET_END;
11292 		return size == sizeof(__u64);
11293 
11294 	case offsetof(struct sk_reuseport_md, hash):
11295 		return size == size_default;
11296 
11297 	case offsetof(struct sk_reuseport_md, sk):
11298 		info->reg_type = PTR_TO_SOCKET;
11299 		return size == sizeof(__u64);
11300 
11301 	case offsetof(struct sk_reuseport_md, migrating_sk):
11302 		info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
11303 		return size == sizeof(__u64);
11304 
11305 	/* Fields that allow narrowing */
11306 	case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
11307 		if (size < sizeof_field(struct sk_buff, protocol))
11308 			return false;
11309 		fallthrough;
11310 	case bpf_ctx_range(struct sk_reuseport_md, ip_protocol):
11311 	case bpf_ctx_range(struct sk_reuseport_md, bind_inany):
11312 	case bpf_ctx_range(struct sk_reuseport_md, len):
11313 		bpf_ctx_record_field_size(info, size_default);
11314 		return bpf_ctx_narrow_access_ok(off, size, size_default);
11315 
11316 	default:
11317 		return false;
11318 	}
11319 }
11320 
11321 #define SK_REUSEPORT_LOAD_FIELD(F) ({					\
11322 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
11323 			      si->dst_reg, si->src_reg,			\
11324 			      bpf_target_off(struct sk_reuseport_kern, F, \
11325 					     sizeof_field(struct sk_reuseport_kern, F), \
11326 					     target_size));		\
11327 	})
11328 
11329 #define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD)				\
11330 	SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,		\
11331 				    struct sk_buff,			\
11332 				    skb,				\
11333 				    SKB_FIELD)
11334 
11335 #define SK_REUSEPORT_LOAD_SK_FIELD(SK_FIELD)				\
11336 	SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,		\
11337 				    struct sock,			\
11338 				    sk,					\
11339 				    SK_FIELD)
11340 
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)11341 static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
11342 					   const struct bpf_insn *si,
11343 					   struct bpf_insn *insn_buf,
11344 					   struct bpf_prog *prog,
11345 					   u32 *target_size)
11346 {
11347 	struct bpf_insn *insn = insn_buf;
11348 
11349 	switch (si->off) {
11350 	case offsetof(struct sk_reuseport_md, data):
11351 		SK_REUSEPORT_LOAD_SKB_FIELD(data);
11352 		break;
11353 
11354 	case offsetof(struct sk_reuseport_md, len):
11355 		SK_REUSEPORT_LOAD_SKB_FIELD(len);
11356 		break;
11357 
11358 	case offsetof(struct sk_reuseport_md, eth_protocol):
11359 		SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
11360 		break;
11361 
11362 	case offsetof(struct sk_reuseport_md, ip_protocol):
11363 		SK_REUSEPORT_LOAD_SK_FIELD(sk_protocol);
11364 		break;
11365 
11366 	case offsetof(struct sk_reuseport_md, data_end):
11367 		SK_REUSEPORT_LOAD_FIELD(data_end);
11368 		break;
11369 
11370 	case offsetof(struct sk_reuseport_md, hash):
11371 		SK_REUSEPORT_LOAD_FIELD(hash);
11372 		break;
11373 
11374 	case offsetof(struct sk_reuseport_md, bind_inany):
11375 		SK_REUSEPORT_LOAD_FIELD(bind_inany);
11376 		break;
11377 
11378 	case offsetof(struct sk_reuseport_md, sk):
11379 		SK_REUSEPORT_LOAD_FIELD(sk);
11380 		break;
11381 
11382 	case offsetof(struct sk_reuseport_md, migrating_sk):
11383 		SK_REUSEPORT_LOAD_FIELD(migrating_sk);
11384 		break;
11385 	}
11386 
11387 	return insn - insn_buf;
11388 }
11389 
11390 const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
11391 	.get_func_proto		= sk_reuseport_func_proto,
11392 	.is_valid_access	= sk_reuseport_is_valid_access,
11393 	.convert_ctx_access	= sk_reuseport_convert_ctx_access,
11394 };
11395 
11396 const struct bpf_prog_ops sk_reuseport_prog_ops = {
11397 };
11398 
11399 DEFINE_STATIC_KEY_FALSE(bpf_sk_lookup_enabled);
11400 EXPORT_SYMBOL(bpf_sk_lookup_enabled);
11401 
BPF_CALL_3(bpf_sk_lookup_assign,struct bpf_sk_lookup_kern *,ctx,struct sock *,sk,u64,flags)11402 BPF_CALL_3(bpf_sk_lookup_assign, struct bpf_sk_lookup_kern *, ctx,
11403 	   struct sock *, sk, u64, flags)
11404 {
11405 	if (unlikely(flags & ~(BPF_SK_LOOKUP_F_REPLACE |
11406 			       BPF_SK_LOOKUP_F_NO_REUSEPORT)))
11407 		return -EINVAL;
11408 	if (unlikely(sk && sk_is_refcounted(sk)))
11409 		return -ESOCKTNOSUPPORT; /* reject non-RCU freed sockets */
11410 	if (unlikely(sk && sk_is_tcp(sk) && sk->sk_state != TCP_LISTEN))
11411 		return -ESOCKTNOSUPPORT; /* only accept TCP socket in LISTEN */
11412 	if (unlikely(sk && sk_is_udp(sk) && sk->sk_state != TCP_CLOSE))
11413 		return -ESOCKTNOSUPPORT; /* only accept UDP socket in CLOSE */
11414 
11415 	/* Check if socket is suitable for packet L3/L4 protocol */
11416 	if (sk && sk->sk_protocol != ctx->protocol)
11417 		return -EPROTOTYPE;
11418 	if (sk && sk->sk_family != ctx->family &&
11419 	    (sk->sk_family == AF_INET || ipv6_only_sock(sk)))
11420 		return -EAFNOSUPPORT;
11421 
11422 	if (ctx->selected_sk && !(flags & BPF_SK_LOOKUP_F_REPLACE))
11423 		return -EEXIST;
11424 
11425 	/* Select socket as lookup result */
11426 	ctx->selected_sk = sk;
11427 	ctx->no_reuseport = flags & BPF_SK_LOOKUP_F_NO_REUSEPORT;
11428 	return 0;
11429 }
11430 
11431 static const struct bpf_func_proto bpf_sk_lookup_assign_proto = {
11432 	.func		= bpf_sk_lookup_assign,
11433 	.gpl_only	= false,
11434 	.ret_type	= RET_INTEGER,
11435 	.arg1_type	= ARG_PTR_TO_CTX,
11436 	.arg2_type	= ARG_PTR_TO_SOCKET_OR_NULL,
11437 	.arg3_type	= ARG_ANYTHING,
11438 };
11439 
11440 static const struct bpf_func_proto *
sk_lookup_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)11441 sk_lookup_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
11442 {
11443 	switch (func_id) {
11444 	case BPF_FUNC_perf_event_output:
11445 		return &bpf_event_output_data_proto;
11446 	case BPF_FUNC_sk_assign:
11447 		return &bpf_sk_lookup_assign_proto;
11448 	case BPF_FUNC_sk_release:
11449 		return &bpf_sk_release_proto;
11450 	default:
11451 		return bpf_sk_base_func_proto(func_id);
11452 	}
11453 }
11454 
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)11455 static bool sk_lookup_is_valid_access(int off, int size,
11456 				      enum bpf_access_type type,
11457 				      const struct bpf_prog *prog,
11458 				      struct bpf_insn_access_aux *info)
11459 {
11460 	if (off < 0 || off >= sizeof(struct bpf_sk_lookup))
11461 		return false;
11462 	if (off % size != 0)
11463 		return false;
11464 	if (type != BPF_READ)
11465 		return false;
11466 
11467 	switch (off) {
11468 	case offsetof(struct bpf_sk_lookup, sk):
11469 		info->reg_type = PTR_TO_SOCKET_OR_NULL;
11470 		return size == sizeof(__u64);
11471 
11472 	case bpf_ctx_range(struct bpf_sk_lookup, family):
11473 	case bpf_ctx_range(struct bpf_sk_lookup, protocol):
11474 	case bpf_ctx_range(struct bpf_sk_lookup, remote_ip4):
11475 	case bpf_ctx_range(struct bpf_sk_lookup, local_ip4):
11476 	case bpf_ctx_range_till(struct bpf_sk_lookup, remote_ip6[0], remote_ip6[3]):
11477 	case bpf_ctx_range_till(struct bpf_sk_lookup, local_ip6[0], local_ip6[3]):
11478 	case bpf_ctx_range(struct bpf_sk_lookup, local_port):
11479 	case bpf_ctx_range(struct bpf_sk_lookup, ingress_ifindex):
11480 		bpf_ctx_record_field_size(info, sizeof(__u32));
11481 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__u32));
11482 
11483 	case bpf_ctx_range(struct bpf_sk_lookup, remote_port):
11484 		/* Allow 4-byte access to 2-byte field for backward compatibility */
11485 		if (size == sizeof(__u32))
11486 			return true;
11487 		bpf_ctx_record_field_size(info, sizeof(__be16));
11488 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__be16));
11489 
11490 	case offsetofend(struct bpf_sk_lookup, remote_port) ...
11491 	     offsetof(struct bpf_sk_lookup, local_ip4) - 1:
11492 		/* Allow access to zero padding for backward compatibility */
11493 		bpf_ctx_record_field_size(info, sizeof(__u16));
11494 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__u16));
11495 
11496 	default:
11497 		return false;
11498 	}
11499 }
11500 
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)11501 static u32 sk_lookup_convert_ctx_access(enum bpf_access_type type,
11502 					const struct bpf_insn *si,
11503 					struct bpf_insn *insn_buf,
11504 					struct bpf_prog *prog,
11505 					u32 *target_size)
11506 {
11507 	struct bpf_insn *insn = insn_buf;
11508 
11509 	switch (si->off) {
11510 	case offsetof(struct bpf_sk_lookup, sk):
11511 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11512 				      offsetof(struct bpf_sk_lookup_kern, selected_sk));
11513 		break;
11514 
11515 	case offsetof(struct bpf_sk_lookup, family):
11516 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11517 				      bpf_target_off(struct bpf_sk_lookup_kern,
11518 						     family, 2, target_size));
11519 		break;
11520 
11521 	case offsetof(struct bpf_sk_lookup, protocol):
11522 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11523 				      bpf_target_off(struct bpf_sk_lookup_kern,
11524 						     protocol, 2, target_size));
11525 		break;
11526 
11527 	case offsetof(struct bpf_sk_lookup, remote_ip4):
11528 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11529 				      bpf_target_off(struct bpf_sk_lookup_kern,
11530 						     v4.saddr, 4, target_size));
11531 		break;
11532 
11533 	case offsetof(struct bpf_sk_lookup, local_ip4):
11534 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11535 				      bpf_target_off(struct bpf_sk_lookup_kern,
11536 						     v4.daddr, 4, target_size));
11537 		break;
11538 
11539 	case bpf_ctx_range_till(struct bpf_sk_lookup,
11540 				remote_ip6[0], remote_ip6[3]): {
11541 #if IS_ENABLED(CONFIG_IPV6)
11542 		int off = si->off;
11543 
11544 		off -= offsetof(struct bpf_sk_lookup, remote_ip6[0]);
11545 		off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11546 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11547 				      offsetof(struct bpf_sk_lookup_kern, v6.saddr));
11548 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11549 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11550 #else
11551 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11552 #endif
11553 		break;
11554 	}
11555 	case bpf_ctx_range_till(struct bpf_sk_lookup,
11556 				local_ip6[0], local_ip6[3]): {
11557 #if IS_ENABLED(CONFIG_IPV6)
11558 		int off = si->off;
11559 
11560 		off -= offsetof(struct bpf_sk_lookup, local_ip6[0]);
11561 		off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11562 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11563 				      offsetof(struct bpf_sk_lookup_kern, v6.daddr));
11564 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11565 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11566 #else
11567 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11568 #endif
11569 		break;
11570 	}
11571 	case offsetof(struct bpf_sk_lookup, remote_port):
11572 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11573 				      bpf_target_off(struct bpf_sk_lookup_kern,
11574 						     sport, 2, target_size));
11575 		break;
11576 
11577 	case offsetofend(struct bpf_sk_lookup, remote_port):
11578 		*target_size = 2;
11579 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11580 		break;
11581 
11582 	case offsetof(struct bpf_sk_lookup, local_port):
11583 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11584 				      bpf_target_off(struct bpf_sk_lookup_kern,
11585 						     dport, 2, target_size));
11586 		break;
11587 
11588 	case offsetof(struct bpf_sk_lookup, ingress_ifindex):
11589 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11590 				      bpf_target_off(struct bpf_sk_lookup_kern,
11591 						     ingress_ifindex, 4, target_size));
11592 		break;
11593 	}
11594 
11595 	return insn - insn_buf;
11596 }
11597 
11598 const struct bpf_prog_ops sk_lookup_prog_ops = {
11599 	.test_run = bpf_prog_test_run_sk_lookup,
11600 };
11601 
11602 const struct bpf_verifier_ops sk_lookup_verifier_ops = {
11603 	.get_func_proto		= sk_lookup_func_proto,
11604 	.is_valid_access	= sk_lookup_is_valid_access,
11605 	.convert_ctx_access	= sk_lookup_convert_ctx_access,
11606 };
11607 
11608 #endif /* CONFIG_INET */
11609 
DEFINE_BPF_DISPATCHER(xdp)11610 DEFINE_BPF_DISPATCHER(xdp)
11611 
11612 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog)
11613 {
11614 	bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(xdp), prev_prog, prog);
11615 }
11616 
BTF_ID_LIST_GLOBAL(btf_sock_ids,MAX_BTF_SOCK_TYPE)11617 BTF_ID_LIST_GLOBAL(btf_sock_ids, MAX_BTF_SOCK_TYPE)
11618 #define BTF_SOCK_TYPE(name, type) BTF_ID(struct, type)
11619 BTF_SOCK_TYPE_xxx
11620 #undef BTF_SOCK_TYPE
11621 
11622 BPF_CALL_1(bpf_skc_to_tcp6_sock, struct sock *, sk)
11623 {
11624 	/* tcp6_sock type is not generated in dwarf and hence btf,
11625 	 * trigger an explicit type generation here.
11626 	 */
11627 	BTF_TYPE_EMIT(struct tcp6_sock);
11628 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP &&
11629 	    sk->sk_family == AF_INET6)
11630 		return (unsigned long)sk;
11631 
11632 	return (unsigned long)NULL;
11633 }
11634 
11635 const struct bpf_func_proto bpf_skc_to_tcp6_sock_proto = {
11636 	.func			= bpf_skc_to_tcp6_sock,
11637 	.gpl_only		= false,
11638 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11639 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11640 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP6],
11641 };
11642 
BPF_CALL_1(bpf_skc_to_tcp_sock,struct sock *,sk)11643 BPF_CALL_1(bpf_skc_to_tcp_sock, struct sock *, sk)
11644 {
11645 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
11646 		return (unsigned long)sk;
11647 
11648 	return (unsigned long)NULL;
11649 }
11650 
11651 const struct bpf_func_proto bpf_skc_to_tcp_sock_proto = {
11652 	.func			= bpf_skc_to_tcp_sock,
11653 	.gpl_only		= false,
11654 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11655 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11656 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP],
11657 };
11658 
BPF_CALL_1(bpf_skc_to_tcp_timewait_sock,struct sock *,sk)11659 BPF_CALL_1(bpf_skc_to_tcp_timewait_sock, struct sock *, sk)
11660 {
11661 	/* BTF types for tcp_timewait_sock and inet_timewait_sock are not
11662 	 * generated if CONFIG_INET=n. Trigger an explicit generation here.
11663 	 */
11664 	BTF_TYPE_EMIT(struct inet_timewait_sock);
11665 	BTF_TYPE_EMIT(struct tcp_timewait_sock);
11666 
11667 #ifdef CONFIG_INET
11668 	if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_TIME_WAIT)
11669 		return (unsigned long)sk;
11670 #endif
11671 
11672 #if IS_BUILTIN(CONFIG_IPV6)
11673 	if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_TIME_WAIT)
11674 		return (unsigned long)sk;
11675 #endif
11676 
11677 	return (unsigned long)NULL;
11678 }
11679 
11680 const struct bpf_func_proto bpf_skc_to_tcp_timewait_sock_proto = {
11681 	.func			= bpf_skc_to_tcp_timewait_sock,
11682 	.gpl_only		= false,
11683 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11684 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11685 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP_TW],
11686 };
11687 
BPF_CALL_1(bpf_skc_to_tcp_request_sock,struct sock *,sk)11688 BPF_CALL_1(bpf_skc_to_tcp_request_sock, struct sock *, sk)
11689 {
11690 #ifdef CONFIG_INET
11691 	if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11692 		return (unsigned long)sk;
11693 #endif
11694 
11695 #if IS_BUILTIN(CONFIG_IPV6)
11696 	if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11697 		return (unsigned long)sk;
11698 #endif
11699 
11700 	return (unsigned long)NULL;
11701 }
11702 
11703 const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto = {
11704 	.func			= bpf_skc_to_tcp_request_sock,
11705 	.gpl_only		= false,
11706 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11707 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11708 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP_REQ],
11709 };
11710 
BPF_CALL_1(bpf_skc_to_udp6_sock,struct sock *,sk)11711 BPF_CALL_1(bpf_skc_to_udp6_sock, struct sock *, sk)
11712 {
11713 	/* udp6_sock type is not generated in dwarf and hence btf,
11714 	 * trigger an explicit type generation here.
11715 	 */
11716 	BTF_TYPE_EMIT(struct udp6_sock);
11717 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_UDP &&
11718 	    sk->sk_type == SOCK_DGRAM && sk->sk_family == AF_INET6)
11719 		return (unsigned long)sk;
11720 
11721 	return (unsigned long)NULL;
11722 }
11723 
11724 const struct bpf_func_proto bpf_skc_to_udp6_sock_proto = {
11725 	.func			= bpf_skc_to_udp6_sock,
11726 	.gpl_only		= false,
11727 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11728 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11729 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_UDP6],
11730 };
11731 
BPF_CALL_1(bpf_skc_to_unix_sock,struct sock *,sk)11732 BPF_CALL_1(bpf_skc_to_unix_sock, struct sock *, sk)
11733 {
11734 	/* unix_sock type is not generated in dwarf and hence btf,
11735 	 * trigger an explicit type generation here.
11736 	 */
11737 	BTF_TYPE_EMIT(struct unix_sock);
11738 	if (sk && sk_fullsock(sk) && sk->sk_family == AF_UNIX)
11739 		return (unsigned long)sk;
11740 
11741 	return (unsigned long)NULL;
11742 }
11743 
11744 const struct bpf_func_proto bpf_skc_to_unix_sock_proto = {
11745 	.func			= bpf_skc_to_unix_sock,
11746 	.gpl_only		= false,
11747 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11748 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11749 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_UNIX],
11750 };
11751 
BPF_CALL_1(bpf_skc_to_mptcp_sock,struct sock *,sk)11752 BPF_CALL_1(bpf_skc_to_mptcp_sock, struct sock *, sk)
11753 {
11754 	BTF_TYPE_EMIT(struct mptcp_sock);
11755 	return (unsigned long)bpf_mptcp_sock_from_subflow(sk);
11756 }
11757 
11758 const struct bpf_func_proto bpf_skc_to_mptcp_sock_proto = {
11759 	.func		= bpf_skc_to_mptcp_sock,
11760 	.gpl_only	= false,
11761 	.ret_type	= RET_PTR_TO_BTF_ID_OR_NULL,
11762 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
11763 	.ret_btf_id	= &btf_sock_ids[BTF_SOCK_TYPE_MPTCP],
11764 };
11765 
BPF_CALL_1(bpf_sock_from_file,struct file *,file)11766 BPF_CALL_1(bpf_sock_from_file, struct file *, file)
11767 {
11768 	return (unsigned long)sock_from_file(file);
11769 }
11770 
11771 BTF_ID_LIST(bpf_sock_from_file_btf_ids)
11772 BTF_ID(struct, socket)
11773 BTF_ID(struct, file)
11774 
11775 const struct bpf_func_proto bpf_sock_from_file_proto = {
11776 	.func		= bpf_sock_from_file,
11777 	.gpl_only	= false,
11778 	.ret_type	= RET_PTR_TO_BTF_ID_OR_NULL,
11779 	.ret_btf_id	= &bpf_sock_from_file_btf_ids[0],
11780 	.arg1_type	= ARG_PTR_TO_BTF_ID,
11781 	.arg1_btf_id	= &bpf_sock_from_file_btf_ids[1],
11782 };
11783 
11784 static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id)11785 bpf_sk_base_func_proto(enum bpf_func_id func_id)
11786 {
11787 	const struct bpf_func_proto *func;
11788 
11789 	switch (func_id) {
11790 	case BPF_FUNC_skc_to_tcp6_sock:
11791 		func = &bpf_skc_to_tcp6_sock_proto;
11792 		break;
11793 	case BPF_FUNC_skc_to_tcp_sock:
11794 		func = &bpf_skc_to_tcp_sock_proto;
11795 		break;
11796 	case BPF_FUNC_skc_to_tcp_timewait_sock:
11797 		func = &bpf_skc_to_tcp_timewait_sock_proto;
11798 		break;
11799 	case BPF_FUNC_skc_to_tcp_request_sock:
11800 		func = &bpf_skc_to_tcp_request_sock_proto;
11801 		break;
11802 	case BPF_FUNC_skc_to_udp6_sock:
11803 		func = &bpf_skc_to_udp6_sock_proto;
11804 		break;
11805 	case BPF_FUNC_skc_to_unix_sock:
11806 		func = &bpf_skc_to_unix_sock_proto;
11807 		break;
11808 	case BPF_FUNC_skc_to_mptcp_sock:
11809 		func = &bpf_skc_to_mptcp_sock_proto;
11810 		break;
11811 	case BPF_FUNC_ktime_get_coarse_ns:
11812 		return &bpf_ktime_get_coarse_ns_proto;
11813 	default:
11814 		return bpf_base_func_proto(func_id);
11815 	}
11816 
11817 	if (!perfmon_capable())
11818 		return NULL;
11819 
11820 	return func;
11821 }
11822 
11823 __diag_push();
11824 __diag_ignore_all("-Wmissing-prototypes",
11825 		  "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)11826 __bpf_kfunc int bpf_dynptr_from_skb(struct sk_buff *skb, u64 flags,
11827 				    struct bpf_dynptr_kern *ptr__uninit)
11828 {
11829 	if (flags) {
11830 		bpf_dynptr_set_null(ptr__uninit);
11831 		return -EINVAL;
11832 	}
11833 
11834 	bpf_dynptr_init(ptr__uninit, skb, BPF_DYNPTR_TYPE_SKB, 0, skb->len);
11835 
11836 	return 0;
11837 }
11838 
bpf_dynptr_from_xdp(struct xdp_buff * xdp,u64 flags,struct bpf_dynptr_kern * ptr__uninit)11839 __bpf_kfunc int bpf_dynptr_from_xdp(struct xdp_buff *xdp, u64 flags,
11840 				    struct bpf_dynptr_kern *ptr__uninit)
11841 {
11842 	if (flags) {
11843 		bpf_dynptr_set_null(ptr__uninit);
11844 		return -EINVAL;
11845 	}
11846 
11847 	bpf_dynptr_init(ptr__uninit, xdp, BPF_DYNPTR_TYPE_XDP, 0, xdp_get_buff_len(xdp));
11848 
11849 	return 0;
11850 }
11851 
bpf_sock_addr_set_sun_path(struct bpf_sock_addr_kern * sa_kern,const u8 * sun_path,u32 sun_path__sz)11852 __bpf_kfunc int bpf_sock_addr_set_sun_path(struct bpf_sock_addr_kern *sa_kern,
11853 					   const u8 *sun_path, u32 sun_path__sz)
11854 {
11855 	struct sockaddr_un *un;
11856 
11857 	if (sa_kern->sk->sk_family != AF_UNIX)
11858 		return -EINVAL;
11859 
11860 	/* We do not allow changing the address to unnamed or larger than the
11861 	 * maximum allowed address size for a unix sockaddr.
11862 	 */
11863 	if (sun_path__sz == 0 || sun_path__sz > UNIX_PATH_MAX)
11864 		return -EINVAL;
11865 
11866 	un = (struct sockaddr_un *)sa_kern->uaddr;
11867 	memcpy(un->sun_path, sun_path, sun_path__sz);
11868 	sa_kern->uaddrlen = offsetof(struct sockaddr_un, sun_path) + sun_path__sz;
11869 
11870 	return 0;
11871 }
11872 __diag_pop();
11873 
bpf_dynptr_from_skb_rdonly(struct sk_buff * skb,u64 flags,struct bpf_dynptr_kern * ptr__uninit)11874 int bpf_dynptr_from_skb_rdonly(struct sk_buff *skb, u64 flags,
11875 			       struct bpf_dynptr_kern *ptr__uninit)
11876 {
11877 	int err;
11878 
11879 	err = bpf_dynptr_from_skb(skb, flags, ptr__uninit);
11880 	if (err)
11881 		return err;
11882 
11883 	bpf_dynptr_set_rdonly(ptr__uninit);
11884 
11885 	return 0;
11886 }
11887 
11888 BTF_SET8_START(bpf_kfunc_check_set_skb)
11889 BTF_ID_FLAGS(func, bpf_dynptr_from_skb)
11890 BTF_SET8_END(bpf_kfunc_check_set_skb)
11891 
11892 BTF_SET8_START(bpf_kfunc_check_set_xdp)
11893 BTF_ID_FLAGS(func, bpf_dynptr_from_xdp)
11894 BTF_SET8_END(bpf_kfunc_check_set_xdp)
11895 
11896 BTF_SET8_START(bpf_kfunc_check_set_sock_addr)
11897 BTF_ID_FLAGS(func, bpf_sock_addr_set_sun_path)
11898 BTF_SET8_END(bpf_kfunc_check_set_sock_addr)
11899 
11900 static const struct btf_kfunc_id_set bpf_kfunc_set_skb = {
11901 	.owner = THIS_MODULE,
11902 	.set = &bpf_kfunc_check_set_skb,
11903 };
11904 
11905 static const struct btf_kfunc_id_set bpf_kfunc_set_xdp = {
11906 	.owner = THIS_MODULE,
11907 	.set = &bpf_kfunc_check_set_xdp,
11908 };
11909 
11910 static const struct btf_kfunc_id_set bpf_kfunc_set_sock_addr = {
11911 	.owner = THIS_MODULE,
11912 	.set = &bpf_kfunc_check_set_sock_addr,
11913 };
11914 
bpf_kfunc_init(void)11915 static int __init bpf_kfunc_init(void)
11916 {
11917 	int ret;
11918 
11919 	ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_kfunc_set_skb);
11920 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_ACT, &bpf_kfunc_set_skb);
11921 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SK_SKB, &bpf_kfunc_set_skb);
11922 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SOCKET_FILTER, &bpf_kfunc_set_skb);
11923 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SKB, &bpf_kfunc_set_skb);
11924 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_OUT, &bpf_kfunc_set_skb);
11925 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_IN, &bpf_kfunc_set_skb);
11926 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_XMIT, &bpf_kfunc_set_skb);
11927 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_LWT_SEG6LOCAL, &bpf_kfunc_set_skb);
11928 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_NETFILTER, &bpf_kfunc_set_skb);
11929 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &bpf_kfunc_set_xdp);
11930 	return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
11931 						&bpf_kfunc_set_sock_addr);
11932 }
11933 late_initcall(bpf_kfunc_init);
11934 
11935 /* Disables missing prototype warnings */
11936 __diag_push();
11937 __diag_ignore_all("-Wmissing-prototypes",
11938 		  "Global functions as their definitions will be in vmlinux BTF");
11939 
11940 /* bpf_sock_destroy: Destroy the given socket with ECONNABORTED error code.
11941  *
11942  * The function expects a non-NULL pointer to a socket, and invokes the
11943  * protocol specific socket destroy handlers.
11944  *
11945  * The helper can only be called from BPF contexts that have acquired the socket
11946  * locks.
11947  *
11948  * Parameters:
11949  * @sock: Pointer to socket to be destroyed
11950  *
11951  * Return:
11952  * On error, may return EPROTONOSUPPORT, EINVAL.
11953  * EPROTONOSUPPORT if protocol specific destroy handler is not supported.
11954  * 0 otherwise
11955  */
bpf_sock_destroy(struct sock_common * sock)11956 __bpf_kfunc int bpf_sock_destroy(struct sock_common *sock)
11957 {
11958 	struct sock *sk = (struct sock *)sock;
11959 
11960 	/* The locking semantics that allow for synchronous execution of the
11961 	 * destroy handlers are only supported for TCP and UDP.
11962 	 * Supporting protocols will need to acquire sock lock in the BPF context
11963 	 * prior to invoking this kfunc.
11964 	 */
11965 	if (!sk->sk_prot->diag_destroy || (sk->sk_protocol != IPPROTO_TCP &&
11966 					   sk->sk_protocol != IPPROTO_UDP))
11967 		return -EOPNOTSUPP;
11968 
11969 	return sk->sk_prot->diag_destroy(sk, ECONNABORTED);
11970 }
11971 
11972 __diag_pop()
11973 
BTF_SET8_START(bpf_sk_iter_kfunc_ids)11974 BTF_SET8_START(bpf_sk_iter_kfunc_ids)
11975 BTF_ID_FLAGS(func, bpf_sock_destroy, KF_TRUSTED_ARGS)
11976 BTF_SET8_END(bpf_sk_iter_kfunc_ids)
11977 
11978 static int tracing_iter_filter(const struct bpf_prog *prog, u32 kfunc_id)
11979 {
11980 	if (btf_id_set8_contains(&bpf_sk_iter_kfunc_ids, kfunc_id) &&
11981 	    prog->expected_attach_type != BPF_TRACE_ITER)
11982 		return -EACCES;
11983 	return 0;
11984 }
11985 
11986 static const struct btf_kfunc_id_set bpf_sk_iter_kfunc_set = {
11987 	.owner = THIS_MODULE,
11988 	.set   = &bpf_sk_iter_kfunc_ids,
11989 	.filter = tracing_iter_filter,
11990 };
11991 
init_subsystem(void)11992 static int init_subsystem(void)
11993 {
11994 	return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_sk_iter_kfunc_set);
11995 }
11996 late_initcall(init_subsystem);
11997