1 /* 2 * Linux Socket Filter - Kernel level socket filtering 3 * 4 * Based on the design of the Berkeley Packet Filter. The new 5 * internal format has been designed by PLUMgrid: 6 * 7 * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com 8 * 9 * Authors: 10 * 11 * Jay Schulist <jschlst@samba.org> 12 * Alexei Starovoitov <ast@plumgrid.com> 13 * Daniel Borkmann <dborkman@redhat.com> 14 * 15 * This program is free software; you can redistribute it and/or 16 * modify it under the terms of the GNU General Public License 17 * as published by the Free Software Foundation; either version 18 * 2 of the License, or (at your option) any later version. 19 * 20 * Andi Kleen - Fix a few bad bugs and races. 21 * Kris Katterjohn - Added many additional checks in bpf_check_classic() 22 */ 23 24 #include <linux/module.h> 25 #include <linux/types.h> 26 #include <linux/mm.h> 27 #include <linux/fcntl.h> 28 #include <linux/socket.h> 29 #include <linux/sock_diag.h> 30 #include <linux/in.h> 31 #include <linux/inet.h> 32 #include <linux/netdevice.h> 33 #include <linux/if_packet.h> 34 #include <linux/if_arp.h> 35 #include <linux/gfp.h> 36 #include <net/inet_common.h> 37 #include <net/ip.h> 38 #include <net/protocol.h> 39 #include <net/netlink.h> 40 #include <linux/skbuff.h> 41 #include <linux/skmsg.h> 42 #include <net/sock.h> 43 #include <net/flow_dissector.h> 44 #include <linux/errno.h> 45 #include <linux/timer.h> 46 #include <linux/uaccess.h> 47 #include <asm/unaligned.h> 48 #include <asm/cmpxchg.h> 49 #include <linux/filter.h> 50 #include <linux/ratelimit.h> 51 #include <linux/seccomp.h> 52 #include <linux/if_vlan.h> 53 #include <linux/bpf.h> 54 #include <net/sch_generic.h> 55 #include <net/cls_cgroup.h> 56 #include <net/dst_metadata.h> 57 #include <net/dst.h> 58 #include <net/sock_reuseport.h> 59 #include <net/busy_poll.h> 60 #include <net/tcp.h> 61 #include <net/xfrm.h> 62 #include <net/udp.h> 63 #include <linux/bpf_trace.h> 64 #include <net/xdp_sock.h> 65 #include <linux/inetdevice.h> 66 #include <net/inet_hashtables.h> 67 #include <net/inet6_hashtables.h> 68 #include <net/ip_fib.h> 69 #include <net/flow.h> 70 #include <net/arp.h> 71 #include <net/ipv6.h> 72 #include <net/net_namespace.h> 73 #include <linux/seg6_local.h> 74 #include <net/seg6.h> 75 #include <net/seg6_local.h> 76 77 /** 78 * sk_filter_trim_cap - run a packet through a socket filter 79 * @sk: sock associated with &sk_buff 80 * @skb: buffer to filter 81 * @cap: limit on how short the eBPF program may trim the packet 82 * 83 * Run the eBPF program and then cut skb->data to correct size returned by 84 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller 85 * than pkt_len we keep whole skb->data. This is the socket level 86 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should 87 * be accepted or -EPERM if the packet should be tossed. 88 * 89 */ 90 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap) 91 { 92 int err; 93 struct sk_filter *filter; 94 95 /* 96 * If the skb was allocated from pfmemalloc reserves, only 97 * allow SOCK_MEMALLOC sockets to use it as this socket is 98 * helping free memory 99 */ 100 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) { 101 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP); 102 return -ENOMEM; 103 } 104 err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb); 105 if (err) 106 return err; 107 108 err = security_sock_rcv_skb(sk, skb); 109 if (err) 110 return err; 111 112 rcu_read_lock(); 113 filter = rcu_dereference(sk->sk_filter); 114 if (filter) { 115 struct sock *save_sk = skb->sk; 116 unsigned int pkt_len; 117 118 skb->sk = sk; 119 pkt_len = bpf_prog_run_save_cb(filter->prog, skb); 120 skb->sk = save_sk; 121 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM; 122 } 123 rcu_read_unlock(); 124 125 return err; 126 } 127 EXPORT_SYMBOL(sk_filter_trim_cap); 128 129 BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb) 130 { 131 return skb_get_poff(skb); 132 } 133 134 BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x) 135 { 136 struct nlattr *nla; 137 138 if (skb_is_nonlinear(skb)) 139 return 0; 140 141 if (skb->len < sizeof(struct nlattr)) 142 return 0; 143 144 if (a > skb->len - sizeof(struct nlattr)) 145 return 0; 146 147 nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x); 148 if (nla) 149 return (void *) nla - (void *) skb->data; 150 151 return 0; 152 } 153 154 BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x) 155 { 156 struct nlattr *nla; 157 158 if (skb_is_nonlinear(skb)) 159 return 0; 160 161 if (skb->len < sizeof(struct nlattr)) 162 return 0; 163 164 if (a > skb->len - sizeof(struct nlattr)) 165 return 0; 166 167 nla = (struct nlattr *) &skb->data[a]; 168 if (nla->nla_len > skb->len - a) 169 return 0; 170 171 nla = nla_find_nested(nla, x); 172 if (nla) 173 return (void *) nla - (void *) skb->data; 174 175 return 0; 176 } 177 178 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *, 179 data, int, headlen, int, offset) 180 { 181 u8 tmp, *ptr; 182 const int len = sizeof(tmp); 183 184 if (offset >= 0) { 185 if (headlen - offset >= len) 186 return *(u8 *)(data + offset); 187 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp))) 188 return tmp; 189 } else { 190 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len); 191 if (likely(ptr)) 192 return *(u8 *)ptr; 193 } 194 195 return -EFAULT; 196 } 197 198 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb, 199 int, offset) 200 { 201 return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len, 202 offset); 203 } 204 205 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *, 206 data, int, headlen, int, offset) 207 { 208 u16 tmp, *ptr; 209 const int len = sizeof(tmp); 210 211 if (offset >= 0) { 212 if (headlen - offset >= len) 213 return get_unaligned_be16(data + offset); 214 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp))) 215 return be16_to_cpu(tmp); 216 } else { 217 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len); 218 if (likely(ptr)) 219 return get_unaligned_be16(ptr); 220 } 221 222 return -EFAULT; 223 } 224 225 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb, 226 int, offset) 227 { 228 return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len, 229 offset); 230 } 231 232 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *, 233 data, int, headlen, int, offset) 234 { 235 u32 tmp, *ptr; 236 const int len = sizeof(tmp); 237 238 if (likely(offset >= 0)) { 239 if (headlen - offset >= len) 240 return get_unaligned_be32(data + offset); 241 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp))) 242 return be32_to_cpu(tmp); 243 } else { 244 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len); 245 if (likely(ptr)) 246 return get_unaligned_be32(ptr); 247 } 248 249 return -EFAULT; 250 } 251 252 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb, 253 int, offset) 254 { 255 return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len, 256 offset); 257 } 258 259 BPF_CALL_0(bpf_get_raw_cpu_id) 260 { 261 return raw_smp_processor_id(); 262 } 263 264 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = { 265 .func = bpf_get_raw_cpu_id, 266 .gpl_only = false, 267 .ret_type = RET_INTEGER, 268 }; 269 270 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg, 271 struct bpf_insn *insn_buf) 272 { 273 struct bpf_insn *insn = insn_buf; 274 275 switch (skb_field) { 276 case SKF_AD_MARK: 277 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4); 278 279 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, 280 offsetof(struct sk_buff, mark)); 281 break; 282 283 case SKF_AD_PKTTYPE: 284 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET()); 285 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX); 286 #ifdef __BIG_ENDIAN_BITFIELD 287 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5); 288 #endif 289 break; 290 291 case SKF_AD_QUEUE: 292 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2); 293 294 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, 295 offsetof(struct sk_buff, queue_mapping)); 296 break; 297 298 case SKF_AD_VLAN_TAG: 299 case SKF_AD_VLAN_TAG_PRESENT: 300 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2); 301 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); 302 303 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */ 304 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, 305 offsetof(struct sk_buff, vlan_tci)); 306 if (skb_field == SKF_AD_VLAN_TAG) { 307 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 308 ~VLAN_TAG_PRESENT); 309 } else { 310 /* dst_reg >>= 12 */ 311 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12); 312 /* dst_reg &= 1 */ 313 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1); 314 } 315 break; 316 } 317 318 return insn - insn_buf; 319 } 320 321 static bool convert_bpf_extensions(struct sock_filter *fp, 322 struct bpf_insn **insnp) 323 { 324 struct bpf_insn *insn = *insnp; 325 u32 cnt; 326 327 switch (fp->k) { 328 case SKF_AD_OFF + SKF_AD_PROTOCOL: 329 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2); 330 331 /* A = *(u16 *) (CTX + offsetof(protocol)) */ 332 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX, 333 offsetof(struct sk_buff, protocol)); 334 /* A = ntohs(A) [emitting a nop or swap16] */ 335 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16); 336 break; 337 338 case SKF_AD_OFF + SKF_AD_PKTTYPE: 339 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn); 340 insn += cnt - 1; 341 break; 342 343 case SKF_AD_OFF + SKF_AD_IFINDEX: 344 case SKF_AD_OFF + SKF_AD_HATYPE: 345 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4); 346 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2); 347 348 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 349 BPF_REG_TMP, BPF_REG_CTX, 350 offsetof(struct sk_buff, dev)); 351 /* if (tmp != 0) goto pc + 1 */ 352 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1); 353 *insn++ = BPF_EXIT_INSN(); 354 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX) 355 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP, 356 offsetof(struct net_device, ifindex)); 357 else 358 *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP, 359 offsetof(struct net_device, type)); 360 break; 361 362 case SKF_AD_OFF + SKF_AD_MARK: 363 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn); 364 insn += cnt - 1; 365 break; 366 367 case SKF_AD_OFF + SKF_AD_RXHASH: 368 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4); 369 370 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, 371 offsetof(struct sk_buff, hash)); 372 break; 373 374 case SKF_AD_OFF + SKF_AD_QUEUE: 375 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn); 376 insn += cnt - 1; 377 break; 378 379 case SKF_AD_OFF + SKF_AD_VLAN_TAG: 380 cnt = convert_skb_access(SKF_AD_VLAN_TAG, 381 BPF_REG_A, BPF_REG_CTX, insn); 382 insn += cnt - 1; 383 break; 384 385 case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT: 386 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT, 387 BPF_REG_A, BPF_REG_CTX, insn); 388 insn += cnt - 1; 389 break; 390 391 case SKF_AD_OFF + SKF_AD_VLAN_TPID: 392 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2); 393 394 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */ 395 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX, 396 offsetof(struct sk_buff, vlan_proto)); 397 /* A = ntohs(A) [emitting a nop or swap16] */ 398 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16); 399 break; 400 401 case SKF_AD_OFF + SKF_AD_PAY_OFFSET: 402 case SKF_AD_OFF + SKF_AD_NLATTR: 403 case SKF_AD_OFF + SKF_AD_NLATTR_NEST: 404 case SKF_AD_OFF + SKF_AD_CPU: 405 case SKF_AD_OFF + SKF_AD_RANDOM: 406 /* arg1 = CTX */ 407 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX); 408 /* arg2 = A */ 409 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A); 410 /* arg3 = X */ 411 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X); 412 /* Emit call(arg1=CTX, arg2=A, arg3=X) */ 413 switch (fp->k) { 414 case SKF_AD_OFF + SKF_AD_PAY_OFFSET: 415 *insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset); 416 break; 417 case SKF_AD_OFF + SKF_AD_NLATTR: 418 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr); 419 break; 420 case SKF_AD_OFF + SKF_AD_NLATTR_NEST: 421 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest); 422 break; 423 case SKF_AD_OFF + SKF_AD_CPU: 424 *insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id); 425 break; 426 case SKF_AD_OFF + SKF_AD_RANDOM: 427 *insn = BPF_EMIT_CALL(bpf_user_rnd_u32); 428 bpf_user_rnd_init_once(); 429 break; 430 } 431 break; 432 433 case SKF_AD_OFF + SKF_AD_ALU_XOR_X: 434 /* A ^= X */ 435 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X); 436 break; 437 438 default: 439 /* This is just a dummy call to avoid letting the compiler 440 * evict __bpf_call_base() as an optimization. Placed here 441 * where no-one bothers. 442 */ 443 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0); 444 return false; 445 } 446 447 *insnp = insn; 448 return true; 449 } 450 451 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp) 452 { 453 const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS); 454 int size = bpf_size_to_bytes(BPF_SIZE(fp->code)); 455 bool endian = BPF_SIZE(fp->code) == BPF_H || 456 BPF_SIZE(fp->code) == BPF_W; 457 bool indirect = BPF_MODE(fp->code) == BPF_IND; 458 const int ip_align = NET_IP_ALIGN; 459 struct bpf_insn *insn = *insnp; 460 int offset = fp->k; 461 462 if (!indirect && 463 ((unaligned_ok && offset >= 0) || 464 (!unaligned_ok && offset >= 0 && 465 offset + ip_align >= 0 && 466 offset + ip_align % size == 0))) { 467 bool ldx_off_ok = offset <= S16_MAX; 468 469 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H); 470 *insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset); 471 *insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP, 472 size, 2 + endian + (!ldx_off_ok * 2)); 473 if (ldx_off_ok) { 474 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A, 475 BPF_REG_D, offset); 476 } else { 477 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D); 478 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset); 479 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A, 480 BPF_REG_TMP, 0); 481 } 482 if (endian) 483 *insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8); 484 *insn++ = BPF_JMP_A(8); 485 } 486 487 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX); 488 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D); 489 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H); 490 if (!indirect) { 491 *insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset); 492 } else { 493 *insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X); 494 if (fp->k) 495 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset); 496 } 497 498 switch (BPF_SIZE(fp->code)) { 499 case BPF_B: 500 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8); 501 break; 502 case BPF_H: 503 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16); 504 break; 505 case BPF_W: 506 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32); 507 break; 508 default: 509 return false; 510 } 511 512 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2); 513 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 514 *insn = BPF_EXIT_INSN(); 515 516 *insnp = insn; 517 return true; 518 } 519 520 /** 521 * bpf_convert_filter - convert filter program 522 * @prog: the user passed filter program 523 * @len: the length of the user passed filter program 524 * @new_prog: allocated 'struct bpf_prog' or NULL 525 * @new_len: pointer to store length of converted program 526 * @seen_ld_abs: bool whether we've seen ld_abs/ind 527 * 528 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn' 529 * style extended BPF (eBPF). 530 * Conversion workflow: 531 * 532 * 1) First pass for calculating the new program length: 533 * bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs) 534 * 535 * 2) 2nd pass to remap in two passes: 1st pass finds new 536 * jump offsets, 2nd pass remapping: 537 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs) 538 */ 539 static int bpf_convert_filter(struct sock_filter *prog, int len, 540 struct bpf_prog *new_prog, int *new_len, 541 bool *seen_ld_abs) 542 { 543 int new_flen = 0, pass = 0, target, i, stack_off; 544 struct bpf_insn *new_insn, *first_insn = NULL; 545 struct sock_filter *fp; 546 int *addrs = NULL; 547 u8 bpf_src; 548 549 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK); 550 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG); 551 552 if (len <= 0 || len > BPF_MAXINSNS) 553 return -EINVAL; 554 555 if (new_prog) { 556 first_insn = new_prog->insnsi; 557 addrs = kcalloc(len, sizeof(*addrs), 558 GFP_KERNEL | __GFP_NOWARN); 559 if (!addrs) 560 return -ENOMEM; 561 } 562 563 do_pass: 564 new_insn = first_insn; 565 fp = prog; 566 567 /* Classic BPF related prologue emission. */ 568 if (new_prog) { 569 /* Classic BPF expects A and X to be reset first. These need 570 * to be guaranteed to be the first two instructions. 571 */ 572 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 573 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X); 574 575 /* All programs must keep CTX in callee saved BPF_REG_CTX. 576 * In eBPF case it's done by the compiler, here we need to 577 * do this ourself. Initial CTX is present in BPF_REG_ARG1. 578 */ 579 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1); 580 if (*seen_ld_abs) { 581 /* For packet access in classic BPF, cache skb->data 582 * in callee-saved BPF R8 and skb->len - skb->data_len 583 * (headlen) in BPF R9. Since classic BPF is read-only 584 * on CTX, we only need to cache it once. 585 */ 586 *new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data), 587 BPF_REG_D, BPF_REG_CTX, 588 offsetof(struct sk_buff, data)); 589 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX, 590 offsetof(struct sk_buff, len)); 591 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX, 592 offsetof(struct sk_buff, data_len)); 593 *new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP); 594 } 595 } else { 596 new_insn += 3; 597 } 598 599 for (i = 0; i < len; fp++, i++) { 600 struct bpf_insn tmp_insns[32] = { }; 601 struct bpf_insn *insn = tmp_insns; 602 603 if (addrs) 604 addrs[i] = new_insn - first_insn; 605 606 switch (fp->code) { 607 /* All arithmetic insns and skb loads map as-is. */ 608 case BPF_ALU | BPF_ADD | BPF_X: 609 case BPF_ALU | BPF_ADD | BPF_K: 610 case BPF_ALU | BPF_SUB | BPF_X: 611 case BPF_ALU | BPF_SUB | BPF_K: 612 case BPF_ALU | BPF_AND | BPF_X: 613 case BPF_ALU | BPF_AND | BPF_K: 614 case BPF_ALU | BPF_OR | BPF_X: 615 case BPF_ALU | BPF_OR | BPF_K: 616 case BPF_ALU | BPF_LSH | BPF_X: 617 case BPF_ALU | BPF_LSH | BPF_K: 618 case BPF_ALU | BPF_RSH | BPF_X: 619 case BPF_ALU | BPF_RSH | BPF_K: 620 case BPF_ALU | BPF_XOR | BPF_X: 621 case BPF_ALU | BPF_XOR | BPF_K: 622 case BPF_ALU | BPF_MUL | BPF_X: 623 case BPF_ALU | BPF_MUL | BPF_K: 624 case BPF_ALU | BPF_DIV | BPF_X: 625 case BPF_ALU | BPF_DIV | BPF_K: 626 case BPF_ALU | BPF_MOD | BPF_X: 627 case BPF_ALU | BPF_MOD | BPF_K: 628 case BPF_ALU | BPF_NEG: 629 case BPF_LD | BPF_ABS | BPF_W: 630 case BPF_LD | BPF_ABS | BPF_H: 631 case BPF_LD | BPF_ABS | BPF_B: 632 case BPF_LD | BPF_IND | BPF_W: 633 case BPF_LD | BPF_IND | BPF_H: 634 case BPF_LD | BPF_IND | BPF_B: 635 /* Check for overloaded BPF extension and 636 * directly convert it if found, otherwise 637 * just move on with mapping. 638 */ 639 if (BPF_CLASS(fp->code) == BPF_LD && 640 BPF_MODE(fp->code) == BPF_ABS && 641 convert_bpf_extensions(fp, &insn)) 642 break; 643 if (BPF_CLASS(fp->code) == BPF_LD && 644 convert_bpf_ld_abs(fp, &insn)) { 645 *seen_ld_abs = true; 646 break; 647 } 648 649 if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) || 650 fp->code == (BPF_ALU | BPF_MOD | BPF_X)) { 651 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X); 652 /* Error with exception code on div/mod by 0. 653 * For cBPF programs, this was always return 0. 654 */ 655 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2); 656 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 657 *insn++ = BPF_EXIT_INSN(); 658 } 659 660 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k); 661 break; 662 663 /* Jump transformation cannot use BPF block macros 664 * everywhere as offset calculation and target updates 665 * require a bit more work than the rest, i.e. jump 666 * opcodes map as-is, but offsets need adjustment. 667 */ 668 669 #define BPF_EMIT_JMP \ 670 do { \ 671 const s32 off_min = S16_MIN, off_max = S16_MAX; \ 672 s32 off; \ 673 \ 674 if (target >= len || target < 0) \ 675 goto err; \ 676 off = addrs ? addrs[target] - addrs[i] - 1 : 0; \ 677 /* Adjust pc relative offset for 2nd or 3rd insn. */ \ 678 off -= insn - tmp_insns; \ 679 /* Reject anything not fitting into insn->off. */ \ 680 if (off < off_min || off > off_max) \ 681 goto err; \ 682 insn->off = off; \ 683 } while (0) 684 685 case BPF_JMP | BPF_JA: 686 target = i + fp->k + 1; 687 insn->code = fp->code; 688 BPF_EMIT_JMP; 689 break; 690 691 case BPF_JMP | BPF_JEQ | BPF_K: 692 case BPF_JMP | BPF_JEQ | BPF_X: 693 case BPF_JMP | BPF_JSET | BPF_K: 694 case BPF_JMP | BPF_JSET | BPF_X: 695 case BPF_JMP | BPF_JGT | BPF_K: 696 case BPF_JMP | BPF_JGT | BPF_X: 697 case BPF_JMP | BPF_JGE | BPF_K: 698 case BPF_JMP | BPF_JGE | BPF_X: 699 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) { 700 /* BPF immediates are signed, zero extend 701 * immediate into tmp register and use it 702 * in compare insn. 703 */ 704 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k); 705 706 insn->dst_reg = BPF_REG_A; 707 insn->src_reg = BPF_REG_TMP; 708 bpf_src = BPF_X; 709 } else { 710 insn->dst_reg = BPF_REG_A; 711 insn->imm = fp->k; 712 bpf_src = BPF_SRC(fp->code); 713 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0; 714 } 715 716 /* Common case where 'jump_false' is next insn. */ 717 if (fp->jf == 0) { 718 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; 719 target = i + fp->jt + 1; 720 BPF_EMIT_JMP; 721 break; 722 } 723 724 /* Convert some jumps when 'jump_true' is next insn. */ 725 if (fp->jt == 0) { 726 switch (BPF_OP(fp->code)) { 727 case BPF_JEQ: 728 insn->code = BPF_JMP | BPF_JNE | bpf_src; 729 break; 730 case BPF_JGT: 731 insn->code = BPF_JMP | BPF_JLE | bpf_src; 732 break; 733 case BPF_JGE: 734 insn->code = BPF_JMP | BPF_JLT | bpf_src; 735 break; 736 default: 737 goto jmp_rest; 738 } 739 740 target = i + fp->jf + 1; 741 BPF_EMIT_JMP; 742 break; 743 } 744 jmp_rest: 745 /* Other jumps are mapped into two insns: Jxx and JA. */ 746 target = i + fp->jt + 1; 747 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; 748 BPF_EMIT_JMP; 749 insn++; 750 751 insn->code = BPF_JMP | BPF_JA; 752 target = i + fp->jf + 1; 753 BPF_EMIT_JMP; 754 break; 755 756 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */ 757 case BPF_LDX | BPF_MSH | BPF_B: { 758 struct sock_filter tmp = { 759 .code = BPF_LD | BPF_ABS | BPF_B, 760 .k = fp->k, 761 }; 762 763 *seen_ld_abs = true; 764 765 /* X = A */ 766 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 767 /* A = BPF_R0 = *(u8 *) (skb->data + K) */ 768 convert_bpf_ld_abs(&tmp, &insn); 769 insn++; 770 /* A &= 0xf */ 771 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf); 772 /* A <<= 2 */ 773 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2); 774 /* tmp = X */ 775 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X); 776 /* X = A */ 777 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 778 /* A = tmp */ 779 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP); 780 break; 781 } 782 /* RET_K is remaped into 2 insns. RET_A case doesn't need an 783 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A. 784 */ 785 case BPF_RET | BPF_A: 786 case BPF_RET | BPF_K: 787 if (BPF_RVAL(fp->code) == BPF_K) 788 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0, 789 0, fp->k); 790 *insn = BPF_EXIT_INSN(); 791 break; 792 793 /* Store to stack. */ 794 case BPF_ST: 795 case BPF_STX: 796 stack_off = fp->k * 4 + 4; 797 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) == 798 BPF_ST ? BPF_REG_A : BPF_REG_X, 799 -stack_off); 800 /* check_load_and_stores() verifies that classic BPF can 801 * load from stack only after write, so tracking 802 * stack_depth for ST|STX insns is enough 803 */ 804 if (new_prog && new_prog->aux->stack_depth < stack_off) 805 new_prog->aux->stack_depth = stack_off; 806 break; 807 808 /* Load from stack. */ 809 case BPF_LD | BPF_MEM: 810 case BPF_LDX | BPF_MEM: 811 stack_off = fp->k * 4 + 4; 812 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? 813 BPF_REG_A : BPF_REG_X, BPF_REG_FP, 814 -stack_off); 815 break; 816 817 /* A = K or X = K */ 818 case BPF_LD | BPF_IMM: 819 case BPF_LDX | BPF_IMM: 820 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ? 821 BPF_REG_A : BPF_REG_X, fp->k); 822 break; 823 824 /* X = A */ 825 case BPF_MISC | BPF_TAX: 826 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 827 break; 828 829 /* A = X */ 830 case BPF_MISC | BPF_TXA: 831 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X); 832 break; 833 834 /* A = skb->len or X = skb->len */ 835 case BPF_LD | BPF_W | BPF_LEN: 836 case BPF_LDX | BPF_W | BPF_LEN: 837 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? 838 BPF_REG_A : BPF_REG_X, BPF_REG_CTX, 839 offsetof(struct sk_buff, len)); 840 break; 841 842 /* Access seccomp_data fields. */ 843 case BPF_LDX | BPF_ABS | BPF_W: 844 /* A = *(u32 *) (ctx + K) */ 845 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k); 846 break; 847 848 /* Unknown instruction. */ 849 default: 850 goto err; 851 } 852 853 insn++; 854 if (new_prog) 855 memcpy(new_insn, tmp_insns, 856 sizeof(*insn) * (insn - tmp_insns)); 857 new_insn += insn - tmp_insns; 858 } 859 860 if (!new_prog) { 861 /* Only calculating new length. */ 862 *new_len = new_insn - first_insn; 863 if (*seen_ld_abs) 864 *new_len += 4; /* Prologue bits. */ 865 return 0; 866 } 867 868 pass++; 869 if (new_flen != new_insn - first_insn) { 870 new_flen = new_insn - first_insn; 871 if (pass > 2) 872 goto err; 873 goto do_pass; 874 } 875 876 kfree(addrs); 877 BUG_ON(*new_len != new_flen); 878 return 0; 879 err: 880 kfree(addrs); 881 return -EINVAL; 882 } 883 884 /* Security: 885 * 886 * As we dont want to clear mem[] array for each packet going through 887 * __bpf_prog_run(), we check that filter loaded by user never try to read 888 * a cell if not previously written, and we check all branches to be sure 889 * a malicious user doesn't try to abuse us. 890 */ 891 static int check_load_and_stores(const struct sock_filter *filter, int flen) 892 { 893 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */ 894 int pc, ret = 0; 895 896 BUILD_BUG_ON(BPF_MEMWORDS > 16); 897 898 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL); 899 if (!masks) 900 return -ENOMEM; 901 902 memset(masks, 0xff, flen * sizeof(*masks)); 903 904 for (pc = 0; pc < flen; pc++) { 905 memvalid &= masks[pc]; 906 907 switch (filter[pc].code) { 908 case BPF_ST: 909 case BPF_STX: 910 memvalid |= (1 << filter[pc].k); 911 break; 912 case BPF_LD | BPF_MEM: 913 case BPF_LDX | BPF_MEM: 914 if (!(memvalid & (1 << filter[pc].k))) { 915 ret = -EINVAL; 916 goto error; 917 } 918 break; 919 case BPF_JMP | BPF_JA: 920 /* A jump must set masks on target */ 921 masks[pc + 1 + filter[pc].k] &= memvalid; 922 memvalid = ~0; 923 break; 924 case BPF_JMP | BPF_JEQ | BPF_K: 925 case BPF_JMP | BPF_JEQ | BPF_X: 926 case BPF_JMP | BPF_JGE | BPF_K: 927 case BPF_JMP | BPF_JGE | BPF_X: 928 case BPF_JMP | BPF_JGT | BPF_K: 929 case BPF_JMP | BPF_JGT | BPF_X: 930 case BPF_JMP | BPF_JSET | BPF_K: 931 case BPF_JMP | BPF_JSET | BPF_X: 932 /* A jump must set masks on targets */ 933 masks[pc + 1 + filter[pc].jt] &= memvalid; 934 masks[pc + 1 + filter[pc].jf] &= memvalid; 935 memvalid = ~0; 936 break; 937 } 938 } 939 error: 940 kfree(masks); 941 return ret; 942 } 943 944 static bool chk_code_allowed(u16 code_to_probe) 945 { 946 static const bool codes[] = { 947 /* 32 bit ALU operations */ 948 [BPF_ALU | BPF_ADD | BPF_K] = true, 949 [BPF_ALU | BPF_ADD | BPF_X] = true, 950 [BPF_ALU | BPF_SUB | BPF_K] = true, 951 [BPF_ALU | BPF_SUB | BPF_X] = true, 952 [BPF_ALU | BPF_MUL | BPF_K] = true, 953 [BPF_ALU | BPF_MUL | BPF_X] = true, 954 [BPF_ALU | BPF_DIV | BPF_K] = true, 955 [BPF_ALU | BPF_DIV | BPF_X] = true, 956 [BPF_ALU | BPF_MOD | BPF_K] = true, 957 [BPF_ALU | BPF_MOD | BPF_X] = true, 958 [BPF_ALU | BPF_AND | BPF_K] = true, 959 [BPF_ALU | BPF_AND | BPF_X] = true, 960 [BPF_ALU | BPF_OR | BPF_K] = true, 961 [BPF_ALU | BPF_OR | BPF_X] = true, 962 [BPF_ALU | BPF_XOR | BPF_K] = true, 963 [BPF_ALU | BPF_XOR | BPF_X] = true, 964 [BPF_ALU | BPF_LSH | BPF_K] = true, 965 [BPF_ALU | BPF_LSH | BPF_X] = true, 966 [BPF_ALU | BPF_RSH | BPF_K] = true, 967 [BPF_ALU | BPF_RSH | BPF_X] = true, 968 [BPF_ALU | BPF_NEG] = true, 969 /* Load instructions */ 970 [BPF_LD | BPF_W | BPF_ABS] = true, 971 [BPF_LD | BPF_H | BPF_ABS] = true, 972 [BPF_LD | BPF_B | BPF_ABS] = true, 973 [BPF_LD | BPF_W | BPF_LEN] = true, 974 [BPF_LD | BPF_W | BPF_IND] = true, 975 [BPF_LD | BPF_H | BPF_IND] = true, 976 [BPF_LD | BPF_B | BPF_IND] = true, 977 [BPF_LD | BPF_IMM] = true, 978 [BPF_LD | BPF_MEM] = true, 979 [BPF_LDX | BPF_W | BPF_LEN] = true, 980 [BPF_LDX | BPF_B | BPF_MSH] = true, 981 [BPF_LDX | BPF_IMM] = true, 982 [BPF_LDX | BPF_MEM] = true, 983 /* Store instructions */ 984 [BPF_ST] = true, 985 [BPF_STX] = true, 986 /* Misc instructions */ 987 [BPF_MISC | BPF_TAX] = true, 988 [BPF_MISC | BPF_TXA] = true, 989 /* Return instructions */ 990 [BPF_RET | BPF_K] = true, 991 [BPF_RET | BPF_A] = true, 992 /* Jump instructions */ 993 [BPF_JMP | BPF_JA] = true, 994 [BPF_JMP | BPF_JEQ | BPF_K] = true, 995 [BPF_JMP | BPF_JEQ | BPF_X] = true, 996 [BPF_JMP | BPF_JGE | BPF_K] = true, 997 [BPF_JMP | BPF_JGE | BPF_X] = true, 998 [BPF_JMP | BPF_JGT | BPF_K] = true, 999 [BPF_JMP | BPF_JGT | BPF_X] = true, 1000 [BPF_JMP | BPF_JSET | BPF_K] = true, 1001 [BPF_JMP | BPF_JSET | BPF_X] = true, 1002 }; 1003 1004 if (code_to_probe >= ARRAY_SIZE(codes)) 1005 return false; 1006 1007 return codes[code_to_probe]; 1008 } 1009 1010 static bool bpf_check_basics_ok(const struct sock_filter *filter, 1011 unsigned int flen) 1012 { 1013 if (filter == NULL) 1014 return false; 1015 if (flen == 0 || flen > BPF_MAXINSNS) 1016 return false; 1017 1018 return true; 1019 } 1020 1021 /** 1022 * bpf_check_classic - verify socket filter code 1023 * @filter: filter to verify 1024 * @flen: length of filter 1025 * 1026 * Check the user's filter code. If we let some ugly 1027 * filter code slip through kaboom! The filter must contain 1028 * no references or jumps that are out of range, no illegal 1029 * instructions, and must end with a RET instruction. 1030 * 1031 * All jumps are forward as they are not signed. 1032 * 1033 * Returns 0 if the rule set is legal or -EINVAL if not. 1034 */ 1035 static int bpf_check_classic(const struct sock_filter *filter, 1036 unsigned int flen) 1037 { 1038 bool anc_found; 1039 int pc; 1040 1041 /* Check the filter code now */ 1042 for (pc = 0; pc < flen; pc++) { 1043 const struct sock_filter *ftest = &filter[pc]; 1044 1045 /* May we actually operate on this code? */ 1046 if (!chk_code_allowed(ftest->code)) 1047 return -EINVAL; 1048 1049 /* Some instructions need special checks */ 1050 switch (ftest->code) { 1051 case BPF_ALU | BPF_DIV | BPF_K: 1052 case BPF_ALU | BPF_MOD | BPF_K: 1053 /* Check for division by zero */ 1054 if (ftest->k == 0) 1055 return -EINVAL; 1056 break; 1057 case BPF_ALU | BPF_LSH | BPF_K: 1058 case BPF_ALU | BPF_RSH | BPF_K: 1059 if (ftest->k >= 32) 1060 return -EINVAL; 1061 break; 1062 case BPF_LD | BPF_MEM: 1063 case BPF_LDX | BPF_MEM: 1064 case BPF_ST: 1065 case BPF_STX: 1066 /* Check for invalid memory addresses */ 1067 if (ftest->k >= BPF_MEMWORDS) 1068 return -EINVAL; 1069 break; 1070 case BPF_JMP | BPF_JA: 1071 /* Note, the large ftest->k might cause loops. 1072 * Compare this with conditional jumps below, 1073 * where offsets are limited. --ANK (981016) 1074 */ 1075 if (ftest->k >= (unsigned int)(flen - pc - 1)) 1076 return -EINVAL; 1077 break; 1078 case BPF_JMP | BPF_JEQ | BPF_K: 1079 case BPF_JMP | BPF_JEQ | BPF_X: 1080 case BPF_JMP | BPF_JGE | BPF_K: 1081 case BPF_JMP | BPF_JGE | BPF_X: 1082 case BPF_JMP | BPF_JGT | BPF_K: 1083 case BPF_JMP | BPF_JGT | BPF_X: 1084 case BPF_JMP | BPF_JSET | BPF_K: 1085 case BPF_JMP | BPF_JSET | BPF_X: 1086 /* Both conditionals must be safe */ 1087 if (pc + ftest->jt + 1 >= flen || 1088 pc + ftest->jf + 1 >= flen) 1089 return -EINVAL; 1090 break; 1091 case BPF_LD | BPF_W | BPF_ABS: 1092 case BPF_LD | BPF_H | BPF_ABS: 1093 case BPF_LD | BPF_B | BPF_ABS: 1094 anc_found = false; 1095 if (bpf_anc_helper(ftest) & BPF_ANC) 1096 anc_found = true; 1097 /* Ancillary operation unknown or unsupported */ 1098 if (anc_found == false && ftest->k >= SKF_AD_OFF) 1099 return -EINVAL; 1100 } 1101 } 1102 1103 /* Last instruction must be a RET code */ 1104 switch (filter[flen - 1].code) { 1105 case BPF_RET | BPF_K: 1106 case BPF_RET | BPF_A: 1107 return check_load_and_stores(filter, flen); 1108 } 1109 1110 return -EINVAL; 1111 } 1112 1113 static int bpf_prog_store_orig_filter(struct bpf_prog *fp, 1114 const struct sock_fprog *fprog) 1115 { 1116 unsigned int fsize = bpf_classic_proglen(fprog); 1117 struct sock_fprog_kern *fkprog; 1118 1119 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL); 1120 if (!fp->orig_prog) 1121 return -ENOMEM; 1122 1123 fkprog = fp->orig_prog; 1124 fkprog->len = fprog->len; 1125 1126 fkprog->filter = kmemdup(fp->insns, fsize, 1127 GFP_KERNEL | __GFP_NOWARN); 1128 if (!fkprog->filter) { 1129 kfree(fp->orig_prog); 1130 return -ENOMEM; 1131 } 1132 1133 return 0; 1134 } 1135 1136 static void bpf_release_orig_filter(struct bpf_prog *fp) 1137 { 1138 struct sock_fprog_kern *fprog = fp->orig_prog; 1139 1140 if (fprog) { 1141 kfree(fprog->filter); 1142 kfree(fprog); 1143 } 1144 } 1145 1146 static void __bpf_prog_release(struct bpf_prog *prog) 1147 { 1148 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) { 1149 bpf_prog_put(prog); 1150 } else { 1151 bpf_release_orig_filter(prog); 1152 bpf_prog_free(prog); 1153 } 1154 } 1155 1156 static void __sk_filter_release(struct sk_filter *fp) 1157 { 1158 __bpf_prog_release(fp->prog); 1159 kfree(fp); 1160 } 1161 1162 /** 1163 * sk_filter_release_rcu - Release a socket filter by rcu_head 1164 * @rcu: rcu_head that contains the sk_filter to free 1165 */ 1166 static void sk_filter_release_rcu(struct rcu_head *rcu) 1167 { 1168 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu); 1169 1170 __sk_filter_release(fp); 1171 } 1172 1173 /** 1174 * sk_filter_release - release a socket filter 1175 * @fp: filter to remove 1176 * 1177 * Remove a filter from a socket and release its resources. 1178 */ 1179 static void sk_filter_release(struct sk_filter *fp) 1180 { 1181 if (refcount_dec_and_test(&fp->refcnt)) 1182 call_rcu(&fp->rcu, sk_filter_release_rcu); 1183 } 1184 1185 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) 1186 { 1187 u32 filter_size = bpf_prog_size(fp->prog->len); 1188 1189 atomic_sub(filter_size, &sk->sk_omem_alloc); 1190 sk_filter_release(fp); 1191 } 1192 1193 /* try to charge the socket memory if there is space available 1194 * return true on success 1195 */ 1196 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1197 { 1198 u32 filter_size = bpf_prog_size(fp->prog->len); 1199 1200 /* same check as in sock_kmalloc() */ 1201 if (filter_size <= sysctl_optmem_max && 1202 atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) { 1203 atomic_add(filter_size, &sk->sk_omem_alloc); 1204 return true; 1205 } 1206 return false; 1207 } 1208 1209 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1210 { 1211 if (!refcount_inc_not_zero(&fp->refcnt)) 1212 return false; 1213 1214 if (!__sk_filter_charge(sk, fp)) { 1215 sk_filter_release(fp); 1216 return false; 1217 } 1218 return true; 1219 } 1220 1221 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp) 1222 { 1223 struct sock_filter *old_prog; 1224 struct bpf_prog *old_fp; 1225 int err, new_len, old_len = fp->len; 1226 bool seen_ld_abs = false; 1227 1228 /* We are free to overwrite insns et al right here as it 1229 * won't be used at this point in time anymore internally 1230 * after the migration to the internal BPF instruction 1231 * representation. 1232 */ 1233 BUILD_BUG_ON(sizeof(struct sock_filter) != 1234 sizeof(struct bpf_insn)); 1235 1236 /* Conversion cannot happen on overlapping memory areas, 1237 * so we need to keep the user BPF around until the 2nd 1238 * pass. At this time, the user BPF is stored in fp->insns. 1239 */ 1240 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter), 1241 GFP_KERNEL | __GFP_NOWARN); 1242 if (!old_prog) { 1243 err = -ENOMEM; 1244 goto out_err; 1245 } 1246 1247 /* 1st pass: calculate the new program length. */ 1248 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len, 1249 &seen_ld_abs); 1250 if (err) 1251 goto out_err_free; 1252 1253 /* Expand fp for appending the new filter representation. */ 1254 old_fp = fp; 1255 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0); 1256 if (!fp) { 1257 /* The old_fp is still around in case we couldn't 1258 * allocate new memory, so uncharge on that one. 1259 */ 1260 fp = old_fp; 1261 err = -ENOMEM; 1262 goto out_err_free; 1263 } 1264 1265 fp->len = new_len; 1266 1267 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */ 1268 err = bpf_convert_filter(old_prog, old_len, fp, &new_len, 1269 &seen_ld_abs); 1270 if (err) 1271 /* 2nd bpf_convert_filter() can fail only if it fails 1272 * to allocate memory, remapping must succeed. Note, 1273 * that at this time old_fp has already been released 1274 * by krealloc(). 1275 */ 1276 goto out_err_free; 1277 1278 fp = bpf_prog_select_runtime(fp, &err); 1279 if (err) 1280 goto out_err_free; 1281 1282 kfree(old_prog); 1283 return fp; 1284 1285 out_err_free: 1286 kfree(old_prog); 1287 out_err: 1288 __bpf_prog_release(fp); 1289 return ERR_PTR(err); 1290 } 1291 1292 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp, 1293 bpf_aux_classic_check_t trans) 1294 { 1295 int err; 1296 1297 fp->bpf_func = NULL; 1298 fp->jited = 0; 1299 1300 err = bpf_check_classic(fp->insns, fp->len); 1301 if (err) { 1302 __bpf_prog_release(fp); 1303 return ERR_PTR(err); 1304 } 1305 1306 /* There might be additional checks and transformations 1307 * needed on classic filters, f.e. in case of seccomp. 1308 */ 1309 if (trans) { 1310 err = trans(fp->insns, fp->len); 1311 if (err) { 1312 __bpf_prog_release(fp); 1313 return ERR_PTR(err); 1314 } 1315 } 1316 1317 /* Probe if we can JIT compile the filter and if so, do 1318 * the compilation of the filter. 1319 */ 1320 bpf_jit_compile(fp); 1321 1322 /* JIT compiler couldn't process this filter, so do the 1323 * internal BPF translation for the optimized interpreter. 1324 */ 1325 if (!fp->jited) 1326 fp = bpf_migrate_filter(fp); 1327 1328 return fp; 1329 } 1330 1331 /** 1332 * bpf_prog_create - create an unattached filter 1333 * @pfp: the unattached filter that is created 1334 * @fprog: the filter program 1335 * 1336 * Create a filter independent of any socket. We first run some 1337 * sanity checks on it to make sure it does not explode on us later. 1338 * If an error occurs or there is insufficient memory for the filter 1339 * a negative errno code is returned. On success the return is zero. 1340 */ 1341 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog) 1342 { 1343 unsigned int fsize = bpf_classic_proglen(fprog); 1344 struct bpf_prog *fp; 1345 1346 /* Make sure new filter is there and in the right amounts. */ 1347 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1348 return -EINVAL; 1349 1350 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1351 if (!fp) 1352 return -ENOMEM; 1353 1354 memcpy(fp->insns, fprog->filter, fsize); 1355 1356 fp->len = fprog->len; 1357 /* Since unattached filters are not copied back to user 1358 * space through sk_get_filter(), we do not need to hold 1359 * a copy here, and can spare us the work. 1360 */ 1361 fp->orig_prog = NULL; 1362 1363 /* bpf_prepare_filter() already takes care of freeing 1364 * memory in case something goes wrong. 1365 */ 1366 fp = bpf_prepare_filter(fp, NULL); 1367 if (IS_ERR(fp)) 1368 return PTR_ERR(fp); 1369 1370 *pfp = fp; 1371 return 0; 1372 } 1373 EXPORT_SYMBOL_GPL(bpf_prog_create); 1374 1375 /** 1376 * bpf_prog_create_from_user - create an unattached filter from user buffer 1377 * @pfp: the unattached filter that is created 1378 * @fprog: the filter program 1379 * @trans: post-classic verifier transformation handler 1380 * @save_orig: save classic BPF program 1381 * 1382 * This function effectively does the same as bpf_prog_create(), only 1383 * that it builds up its insns buffer from user space provided buffer. 1384 * It also allows for passing a bpf_aux_classic_check_t handler. 1385 */ 1386 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 1387 bpf_aux_classic_check_t trans, bool save_orig) 1388 { 1389 unsigned int fsize = bpf_classic_proglen(fprog); 1390 struct bpf_prog *fp; 1391 int err; 1392 1393 /* Make sure new filter is there and in the right amounts. */ 1394 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1395 return -EINVAL; 1396 1397 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1398 if (!fp) 1399 return -ENOMEM; 1400 1401 if (copy_from_user(fp->insns, fprog->filter, fsize)) { 1402 __bpf_prog_free(fp); 1403 return -EFAULT; 1404 } 1405 1406 fp->len = fprog->len; 1407 fp->orig_prog = NULL; 1408 1409 if (save_orig) { 1410 err = bpf_prog_store_orig_filter(fp, fprog); 1411 if (err) { 1412 __bpf_prog_free(fp); 1413 return -ENOMEM; 1414 } 1415 } 1416 1417 /* bpf_prepare_filter() already takes care of freeing 1418 * memory in case something goes wrong. 1419 */ 1420 fp = bpf_prepare_filter(fp, trans); 1421 if (IS_ERR(fp)) 1422 return PTR_ERR(fp); 1423 1424 *pfp = fp; 1425 return 0; 1426 } 1427 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user); 1428 1429 void bpf_prog_destroy(struct bpf_prog *fp) 1430 { 1431 __bpf_prog_release(fp); 1432 } 1433 EXPORT_SYMBOL_GPL(bpf_prog_destroy); 1434 1435 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk) 1436 { 1437 struct sk_filter *fp, *old_fp; 1438 1439 fp = kmalloc(sizeof(*fp), GFP_KERNEL); 1440 if (!fp) 1441 return -ENOMEM; 1442 1443 fp->prog = prog; 1444 1445 if (!__sk_filter_charge(sk, fp)) { 1446 kfree(fp); 1447 return -ENOMEM; 1448 } 1449 refcount_set(&fp->refcnt, 1); 1450 1451 old_fp = rcu_dereference_protected(sk->sk_filter, 1452 lockdep_sock_is_held(sk)); 1453 rcu_assign_pointer(sk->sk_filter, fp); 1454 1455 if (old_fp) 1456 sk_filter_uncharge(sk, old_fp); 1457 1458 return 0; 1459 } 1460 1461 static 1462 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk) 1463 { 1464 unsigned int fsize = bpf_classic_proglen(fprog); 1465 struct bpf_prog *prog; 1466 int err; 1467 1468 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 1469 return ERR_PTR(-EPERM); 1470 1471 /* Make sure new filter is there and in the right amounts. */ 1472 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1473 return ERR_PTR(-EINVAL); 1474 1475 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1476 if (!prog) 1477 return ERR_PTR(-ENOMEM); 1478 1479 if (copy_from_user(prog->insns, fprog->filter, fsize)) { 1480 __bpf_prog_free(prog); 1481 return ERR_PTR(-EFAULT); 1482 } 1483 1484 prog->len = fprog->len; 1485 1486 err = bpf_prog_store_orig_filter(prog, fprog); 1487 if (err) { 1488 __bpf_prog_free(prog); 1489 return ERR_PTR(-ENOMEM); 1490 } 1491 1492 /* bpf_prepare_filter() already takes care of freeing 1493 * memory in case something goes wrong. 1494 */ 1495 return bpf_prepare_filter(prog, NULL); 1496 } 1497 1498 /** 1499 * sk_attach_filter - attach a socket filter 1500 * @fprog: the filter program 1501 * @sk: the socket to use 1502 * 1503 * Attach the user's filter code. We first run some sanity checks on 1504 * it to make sure it does not explode on us later. If an error 1505 * occurs or there is insufficient memory for the filter a negative 1506 * errno code is returned. On success the return is zero. 1507 */ 1508 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk) 1509 { 1510 struct bpf_prog *prog = __get_filter(fprog, sk); 1511 int err; 1512 1513 if (IS_ERR(prog)) 1514 return PTR_ERR(prog); 1515 1516 err = __sk_attach_prog(prog, sk); 1517 if (err < 0) { 1518 __bpf_prog_release(prog); 1519 return err; 1520 } 1521 1522 return 0; 1523 } 1524 EXPORT_SYMBOL_GPL(sk_attach_filter); 1525 1526 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk) 1527 { 1528 struct bpf_prog *prog = __get_filter(fprog, sk); 1529 int err; 1530 1531 if (IS_ERR(prog)) 1532 return PTR_ERR(prog); 1533 1534 if (bpf_prog_size(prog->len) > sysctl_optmem_max) 1535 err = -ENOMEM; 1536 else 1537 err = reuseport_attach_prog(sk, prog); 1538 1539 if (err) 1540 __bpf_prog_release(prog); 1541 1542 return err; 1543 } 1544 1545 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk) 1546 { 1547 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 1548 return ERR_PTR(-EPERM); 1549 1550 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER); 1551 } 1552 1553 int sk_attach_bpf(u32 ufd, struct sock *sk) 1554 { 1555 struct bpf_prog *prog = __get_bpf(ufd, sk); 1556 int err; 1557 1558 if (IS_ERR(prog)) 1559 return PTR_ERR(prog); 1560 1561 err = __sk_attach_prog(prog, sk); 1562 if (err < 0) { 1563 bpf_prog_put(prog); 1564 return err; 1565 } 1566 1567 return 0; 1568 } 1569 1570 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk) 1571 { 1572 struct bpf_prog *prog; 1573 int err; 1574 1575 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 1576 return -EPERM; 1577 1578 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER); 1579 if (IS_ERR(prog) && PTR_ERR(prog) == -EINVAL) 1580 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT); 1581 if (IS_ERR(prog)) 1582 return PTR_ERR(prog); 1583 1584 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) { 1585 /* Like other non BPF_PROG_TYPE_SOCKET_FILTER 1586 * bpf prog (e.g. sockmap). It depends on the 1587 * limitation imposed by bpf_prog_load(). 1588 * Hence, sysctl_optmem_max is not checked. 1589 */ 1590 if ((sk->sk_type != SOCK_STREAM && 1591 sk->sk_type != SOCK_DGRAM) || 1592 (sk->sk_protocol != IPPROTO_UDP && 1593 sk->sk_protocol != IPPROTO_TCP) || 1594 (sk->sk_family != AF_INET && 1595 sk->sk_family != AF_INET6)) { 1596 err = -ENOTSUPP; 1597 goto err_prog_put; 1598 } 1599 } else { 1600 /* BPF_PROG_TYPE_SOCKET_FILTER */ 1601 if (bpf_prog_size(prog->len) > sysctl_optmem_max) { 1602 err = -ENOMEM; 1603 goto err_prog_put; 1604 } 1605 } 1606 1607 err = reuseport_attach_prog(sk, prog); 1608 err_prog_put: 1609 if (err) 1610 bpf_prog_put(prog); 1611 1612 return err; 1613 } 1614 1615 void sk_reuseport_prog_free(struct bpf_prog *prog) 1616 { 1617 if (!prog) 1618 return; 1619 1620 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) 1621 bpf_prog_put(prog); 1622 else 1623 bpf_prog_destroy(prog); 1624 } 1625 1626 struct bpf_scratchpad { 1627 union { 1628 __be32 diff[MAX_BPF_STACK / sizeof(__be32)]; 1629 u8 buff[MAX_BPF_STACK]; 1630 }; 1631 }; 1632 1633 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp); 1634 1635 static inline int __bpf_try_make_writable(struct sk_buff *skb, 1636 unsigned int write_len) 1637 { 1638 return skb_ensure_writable(skb, write_len); 1639 } 1640 1641 static inline int bpf_try_make_writable(struct sk_buff *skb, 1642 unsigned int write_len) 1643 { 1644 int err = __bpf_try_make_writable(skb, write_len); 1645 1646 bpf_compute_data_pointers(skb); 1647 return err; 1648 } 1649 1650 static int bpf_try_make_head_writable(struct sk_buff *skb) 1651 { 1652 return bpf_try_make_writable(skb, skb_headlen(skb)); 1653 } 1654 1655 static inline void bpf_push_mac_rcsum(struct sk_buff *skb) 1656 { 1657 if (skb_at_tc_ingress(skb)) 1658 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len); 1659 } 1660 1661 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb) 1662 { 1663 if (skb_at_tc_ingress(skb)) 1664 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len); 1665 } 1666 1667 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset, 1668 const void *, from, u32, len, u64, flags) 1669 { 1670 void *ptr; 1671 1672 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH))) 1673 return -EINVAL; 1674 if (unlikely(offset > 0xffff)) 1675 return -EFAULT; 1676 if (unlikely(bpf_try_make_writable(skb, offset + len))) 1677 return -EFAULT; 1678 1679 ptr = skb->data + offset; 1680 if (flags & BPF_F_RECOMPUTE_CSUM) 1681 __skb_postpull_rcsum(skb, ptr, len, offset); 1682 1683 memcpy(ptr, from, len); 1684 1685 if (flags & BPF_F_RECOMPUTE_CSUM) 1686 __skb_postpush_rcsum(skb, ptr, len, offset); 1687 if (flags & BPF_F_INVALIDATE_HASH) 1688 skb_clear_hash(skb); 1689 1690 return 0; 1691 } 1692 1693 static const struct bpf_func_proto bpf_skb_store_bytes_proto = { 1694 .func = bpf_skb_store_bytes, 1695 .gpl_only = false, 1696 .ret_type = RET_INTEGER, 1697 .arg1_type = ARG_PTR_TO_CTX, 1698 .arg2_type = ARG_ANYTHING, 1699 .arg3_type = ARG_PTR_TO_MEM, 1700 .arg4_type = ARG_CONST_SIZE, 1701 .arg5_type = ARG_ANYTHING, 1702 }; 1703 1704 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset, 1705 void *, to, u32, len) 1706 { 1707 void *ptr; 1708 1709 if (unlikely(offset > 0xffff)) 1710 goto err_clear; 1711 1712 ptr = skb_header_pointer(skb, offset, len, to); 1713 if (unlikely(!ptr)) 1714 goto err_clear; 1715 if (ptr != to) 1716 memcpy(to, ptr, len); 1717 1718 return 0; 1719 err_clear: 1720 memset(to, 0, len); 1721 return -EFAULT; 1722 } 1723 1724 static const struct bpf_func_proto bpf_skb_load_bytes_proto = { 1725 .func = bpf_skb_load_bytes, 1726 .gpl_only = false, 1727 .ret_type = RET_INTEGER, 1728 .arg1_type = ARG_PTR_TO_CTX, 1729 .arg2_type = ARG_ANYTHING, 1730 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 1731 .arg4_type = ARG_CONST_SIZE, 1732 }; 1733 1734 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb, 1735 u32, offset, void *, to, u32, len, u32, start_header) 1736 { 1737 u8 *end = skb_tail_pointer(skb); 1738 u8 *net = skb_network_header(skb); 1739 u8 *mac = skb_mac_header(skb); 1740 u8 *ptr; 1741 1742 if (unlikely(offset > 0xffff || len > (end - mac))) 1743 goto err_clear; 1744 1745 switch (start_header) { 1746 case BPF_HDR_START_MAC: 1747 ptr = mac + offset; 1748 break; 1749 case BPF_HDR_START_NET: 1750 ptr = net + offset; 1751 break; 1752 default: 1753 goto err_clear; 1754 } 1755 1756 if (likely(ptr >= mac && ptr + len <= end)) { 1757 memcpy(to, ptr, len); 1758 return 0; 1759 } 1760 1761 err_clear: 1762 memset(to, 0, len); 1763 return -EFAULT; 1764 } 1765 1766 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = { 1767 .func = bpf_skb_load_bytes_relative, 1768 .gpl_only = false, 1769 .ret_type = RET_INTEGER, 1770 .arg1_type = ARG_PTR_TO_CTX, 1771 .arg2_type = ARG_ANYTHING, 1772 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 1773 .arg4_type = ARG_CONST_SIZE, 1774 .arg5_type = ARG_ANYTHING, 1775 }; 1776 1777 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len) 1778 { 1779 /* Idea is the following: should the needed direct read/write 1780 * test fail during runtime, we can pull in more data and redo 1781 * again, since implicitly, we invalidate previous checks here. 1782 * 1783 * Or, since we know how much we need to make read/writeable, 1784 * this can be done once at the program beginning for direct 1785 * access case. By this we overcome limitations of only current 1786 * headroom being accessible. 1787 */ 1788 return bpf_try_make_writable(skb, len ? : skb_headlen(skb)); 1789 } 1790 1791 static const struct bpf_func_proto bpf_skb_pull_data_proto = { 1792 .func = bpf_skb_pull_data, 1793 .gpl_only = false, 1794 .ret_type = RET_INTEGER, 1795 .arg1_type = ARG_PTR_TO_CTX, 1796 .arg2_type = ARG_ANYTHING, 1797 }; 1798 1799 static inline int sk_skb_try_make_writable(struct sk_buff *skb, 1800 unsigned int write_len) 1801 { 1802 int err = __bpf_try_make_writable(skb, write_len); 1803 1804 bpf_compute_data_end_sk_skb(skb); 1805 return err; 1806 } 1807 1808 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len) 1809 { 1810 /* Idea is the following: should the needed direct read/write 1811 * test fail during runtime, we can pull in more data and redo 1812 * again, since implicitly, we invalidate previous checks here. 1813 * 1814 * Or, since we know how much we need to make read/writeable, 1815 * this can be done once at the program beginning for direct 1816 * access case. By this we overcome limitations of only current 1817 * headroom being accessible. 1818 */ 1819 return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb)); 1820 } 1821 1822 static const struct bpf_func_proto sk_skb_pull_data_proto = { 1823 .func = sk_skb_pull_data, 1824 .gpl_only = false, 1825 .ret_type = RET_INTEGER, 1826 .arg1_type = ARG_PTR_TO_CTX, 1827 .arg2_type = ARG_ANYTHING, 1828 }; 1829 1830 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset, 1831 u64, from, u64, to, u64, flags) 1832 { 1833 __sum16 *ptr; 1834 1835 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK))) 1836 return -EINVAL; 1837 if (unlikely(offset > 0xffff || offset & 1)) 1838 return -EFAULT; 1839 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) 1840 return -EFAULT; 1841 1842 ptr = (__sum16 *)(skb->data + offset); 1843 switch (flags & BPF_F_HDR_FIELD_MASK) { 1844 case 0: 1845 if (unlikely(from != 0)) 1846 return -EINVAL; 1847 1848 csum_replace_by_diff(ptr, to); 1849 break; 1850 case 2: 1851 csum_replace2(ptr, from, to); 1852 break; 1853 case 4: 1854 csum_replace4(ptr, from, to); 1855 break; 1856 default: 1857 return -EINVAL; 1858 } 1859 1860 return 0; 1861 } 1862 1863 static const struct bpf_func_proto bpf_l3_csum_replace_proto = { 1864 .func = bpf_l3_csum_replace, 1865 .gpl_only = false, 1866 .ret_type = RET_INTEGER, 1867 .arg1_type = ARG_PTR_TO_CTX, 1868 .arg2_type = ARG_ANYTHING, 1869 .arg3_type = ARG_ANYTHING, 1870 .arg4_type = ARG_ANYTHING, 1871 .arg5_type = ARG_ANYTHING, 1872 }; 1873 1874 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset, 1875 u64, from, u64, to, u64, flags) 1876 { 1877 bool is_pseudo = flags & BPF_F_PSEUDO_HDR; 1878 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0; 1879 bool do_mforce = flags & BPF_F_MARK_ENFORCE; 1880 __sum16 *ptr; 1881 1882 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE | 1883 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK))) 1884 return -EINVAL; 1885 if (unlikely(offset > 0xffff || offset & 1)) 1886 return -EFAULT; 1887 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) 1888 return -EFAULT; 1889 1890 ptr = (__sum16 *)(skb->data + offset); 1891 if (is_mmzero && !do_mforce && !*ptr) 1892 return 0; 1893 1894 switch (flags & BPF_F_HDR_FIELD_MASK) { 1895 case 0: 1896 if (unlikely(from != 0)) 1897 return -EINVAL; 1898 1899 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo); 1900 break; 1901 case 2: 1902 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo); 1903 break; 1904 case 4: 1905 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo); 1906 break; 1907 default: 1908 return -EINVAL; 1909 } 1910 1911 if (is_mmzero && !*ptr) 1912 *ptr = CSUM_MANGLED_0; 1913 return 0; 1914 } 1915 1916 static const struct bpf_func_proto bpf_l4_csum_replace_proto = { 1917 .func = bpf_l4_csum_replace, 1918 .gpl_only = false, 1919 .ret_type = RET_INTEGER, 1920 .arg1_type = ARG_PTR_TO_CTX, 1921 .arg2_type = ARG_ANYTHING, 1922 .arg3_type = ARG_ANYTHING, 1923 .arg4_type = ARG_ANYTHING, 1924 .arg5_type = ARG_ANYTHING, 1925 }; 1926 1927 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size, 1928 __be32 *, to, u32, to_size, __wsum, seed) 1929 { 1930 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp); 1931 u32 diff_size = from_size + to_size; 1932 int i, j = 0; 1933 1934 /* This is quite flexible, some examples: 1935 * 1936 * from_size == 0, to_size > 0, seed := csum --> pushing data 1937 * from_size > 0, to_size == 0, seed := csum --> pulling data 1938 * from_size > 0, to_size > 0, seed := 0 --> diffing data 1939 * 1940 * Even for diffing, from_size and to_size don't need to be equal. 1941 */ 1942 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) || 1943 diff_size > sizeof(sp->diff))) 1944 return -EINVAL; 1945 1946 for (i = 0; i < from_size / sizeof(__be32); i++, j++) 1947 sp->diff[j] = ~from[i]; 1948 for (i = 0; i < to_size / sizeof(__be32); i++, j++) 1949 sp->diff[j] = to[i]; 1950 1951 return csum_partial(sp->diff, diff_size, seed); 1952 } 1953 1954 static const struct bpf_func_proto bpf_csum_diff_proto = { 1955 .func = bpf_csum_diff, 1956 .gpl_only = false, 1957 .pkt_access = true, 1958 .ret_type = RET_INTEGER, 1959 .arg1_type = ARG_PTR_TO_MEM_OR_NULL, 1960 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 1961 .arg3_type = ARG_PTR_TO_MEM_OR_NULL, 1962 .arg4_type = ARG_CONST_SIZE_OR_ZERO, 1963 .arg5_type = ARG_ANYTHING, 1964 }; 1965 1966 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum) 1967 { 1968 /* The interface is to be used in combination with bpf_csum_diff() 1969 * for direct packet writes. csum rotation for alignment as well 1970 * as emulating csum_sub() can be done from the eBPF program. 1971 */ 1972 if (skb->ip_summed == CHECKSUM_COMPLETE) 1973 return (skb->csum = csum_add(skb->csum, csum)); 1974 1975 return -ENOTSUPP; 1976 } 1977 1978 static const struct bpf_func_proto bpf_csum_update_proto = { 1979 .func = bpf_csum_update, 1980 .gpl_only = false, 1981 .ret_type = RET_INTEGER, 1982 .arg1_type = ARG_PTR_TO_CTX, 1983 .arg2_type = ARG_ANYTHING, 1984 }; 1985 1986 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb) 1987 { 1988 return dev_forward_skb(dev, skb); 1989 } 1990 1991 static inline int __bpf_rx_skb_no_mac(struct net_device *dev, 1992 struct sk_buff *skb) 1993 { 1994 int ret = ____dev_forward_skb(dev, skb); 1995 1996 if (likely(!ret)) { 1997 skb->dev = dev; 1998 ret = netif_rx(skb); 1999 } 2000 2001 return ret; 2002 } 2003 2004 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) 2005 { 2006 int ret; 2007 2008 if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) { 2009 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n"); 2010 kfree_skb(skb); 2011 return -ENETDOWN; 2012 } 2013 2014 skb->dev = dev; 2015 2016 __this_cpu_inc(xmit_recursion); 2017 ret = dev_queue_xmit(skb); 2018 __this_cpu_dec(xmit_recursion); 2019 2020 return ret; 2021 } 2022 2023 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev, 2024 u32 flags) 2025 { 2026 /* skb->mac_len is not set on normal egress */ 2027 unsigned int mlen = skb->network_header - skb->mac_header; 2028 2029 __skb_pull(skb, mlen); 2030 2031 /* At ingress, the mac header has already been pulled once. 2032 * At egress, skb_pospull_rcsum has to be done in case that 2033 * the skb is originated from ingress (i.e. a forwarded skb) 2034 * to ensure that rcsum starts at net header. 2035 */ 2036 if (!skb_at_tc_ingress(skb)) 2037 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen); 2038 skb_pop_mac_header(skb); 2039 skb_reset_mac_len(skb); 2040 return flags & BPF_F_INGRESS ? 2041 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb); 2042 } 2043 2044 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev, 2045 u32 flags) 2046 { 2047 /* Verify that a link layer header is carried */ 2048 if (unlikely(skb->mac_header >= skb->network_header)) { 2049 kfree_skb(skb); 2050 return -ERANGE; 2051 } 2052 2053 bpf_push_mac_rcsum(skb); 2054 return flags & BPF_F_INGRESS ? 2055 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb); 2056 } 2057 2058 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev, 2059 u32 flags) 2060 { 2061 if (dev_is_mac_header_xmit(dev)) 2062 return __bpf_redirect_common(skb, dev, flags); 2063 else 2064 return __bpf_redirect_no_mac(skb, dev, flags); 2065 } 2066 2067 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags) 2068 { 2069 struct net_device *dev; 2070 struct sk_buff *clone; 2071 int ret; 2072 2073 if (unlikely(flags & ~(BPF_F_INGRESS))) 2074 return -EINVAL; 2075 2076 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex); 2077 if (unlikely(!dev)) 2078 return -EINVAL; 2079 2080 clone = skb_clone(skb, GFP_ATOMIC); 2081 if (unlikely(!clone)) 2082 return -ENOMEM; 2083 2084 /* For direct write, we need to keep the invariant that the skbs 2085 * we're dealing with need to be uncloned. Should uncloning fail 2086 * here, we need to free the just generated clone to unclone once 2087 * again. 2088 */ 2089 ret = bpf_try_make_head_writable(skb); 2090 if (unlikely(ret)) { 2091 kfree_skb(clone); 2092 return -ENOMEM; 2093 } 2094 2095 return __bpf_redirect(clone, dev, flags); 2096 } 2097 2098 static const struct bpf_func_proto bpf_clone_redirect_proto = { 2099 .func = bpf_clone_redirect, 2100 .gpl_only = false, 2101 .ret_type = RET_INTEGER, 2102 .arg1_type = ARG_PTR_TO_CTX, 2103 .arg2_type = ARG_ANYTHING, 2104 .arg3_type = ARG_ANYTHING, 2105 }; 2106 2107 DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info); 2108 EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info); 2109 2110 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags) 2111 { 2112 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 2113 2114 if (unlikely(flags & ~(BPF_F_INGRESS))) 2115 return TC_ACT_SHOT; 2116 2117 ri->ifindex = ifindex; 2118 ri->flags = flags; 2119 2120 return TC_ACT_REDIRECT; 2121 } 2122 2123 int skb_do_redirect(struct sk_buff *skb) 2124 { 2125 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 2126 struct net_device *dev; 2127 2128 dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex); 2129 ri->ifindex = 0; 2130 if (unlikely(!dev)) { 2131 kfree_skb(skb); 2132 return -EINVAL; 2133 } 2134 2135 return __bpf_redirect(skb, dev, ri->flags); 2136 } 2137 2138 static const struct bpf_func_proto bpf_redirect_proto = { 2139 .func = bpf_redirect, 2140 .gpl_only = false, 2141 .ret_type = RET_INTEGER, 2142 .arg1_type = ARG_ANYTHING, 2143 .arg2_type = ARG_ANYTHING, 2144 }; 2145 2146 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes) 2147 { 2148 msg->apply_bytes = bytes; 2149 return 0; 2150 } 2151 2152 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = { 2153 .func = bpf_msg_apply_bytes, 2154 .gpl_only = false, 2155 .ret_type = RET_INTEGER, 2156 .arg1_type = ARG_PTR_TO_CTX, 2157 .arg2_type = ARG_ANYTHING, 2158 }; 2159 2160 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes) 2161 { 2162 msg->cork_bytes = bytes; 2163 return 0; 2164 } 2165 2166 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = { 2167 .func = bpf_msg_cork_bytes, 2168 .gpl_only = false, 2169 .ret_type = RET_INTEGER, 2170 .arg1_type = ARG_PTR_TO_CTX, 2171 .arg2_type = ARG_ANYTHING, 2172 }; 2173 2174 BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start, 2175 u32, end, u64, flags) 2176 { 2177 u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start; 2178 u32 first_sge, last_sge, i, shift, bytes_sg_total; 2179 struct scatterlist *sge; 2180 u8 *raw, *to, *from; 2181 struct page *page; 2182 2183 if (unlikely(flags || end <= start)) 2184 return -EINVAL; 2185 2186 /* First find the starting scatterlist element */ 2187 i = msg->sg.start; 2188 do { 2189 len = sk_msg_elem(msg, i)->length; 2190 if (start < offset + len) 2191 break; 2192 offset += len; 2193 sk_msg_iter_var_next(i); 2194 } while (i != msg->sg.end); 2195 2196 if (unlikely(start >= offset + len)) 2197 return -EINVAL; 2198 2199 first_sge = i; 2200 /* The start may point into the sg element so we need to also 2201 * account for the headroom. 2202 */ 2203 bytes_sg_total = start - offset + bytes; 2204 if (!msg->sg.copy[i] && bytes_sg_total <= len) 2205 goto out; 2206 2207 /* At this point we need to linearize multiple scatterlist 2208 * elements or a single shared page. Either way we need to 2209 * copy into a linear buffer exclusively owned by BPF. Then 2210 * place the buffer in the scatterlist and fixup the original 2211 * entries by removing the entries now in the linear buffer 2212 * and shifting the remaining entries. For now we do not try 2213 * to copy partial entries to avoid complexity of running out 2214 * of sg_entry slots. The downside is reading a single byte 2215 * will copy the entire sg entry. 2216 */ 2217 do { 2218 copy += sk_msg_elem(msg, i)->length; 2219 sk_msg_iter_var_next(i); 2220 if (bytes_sg_total <= copy) 2221 break; 2222 } while (i != msg->sg.end); 2223 last_sge = i; 2224 2225 if (unlikely(bytes_sg_total > copy)) 2226 return -EINVAL; 2227 2228 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP, 2229 get_order(copy)); 2230 if (unlikely(!page)) 2231 return -ENOMEM; 2232 2233 raw = page_address(page); 2234 i = first_sge; 2235 do { 2236 sge = sk_msg_elem(msg, i); 2237 from = sg_virt(sge); 2238 len = sge->length; 2239 to = raw + poffset; 2240 2241 memcpy(to, from, len); 2242 poffset += len; 2243 sge->length = 0; 2244 put_page(sg_page(sge)); 2245 2246 sk_msg_iter_var_next(i); 2247 } while (i != last_sge); 2248 2249 sg_set_page(&msg->sg.data[first_sge], page, copy, 0); 2250 2251 /* To repair sg ring we need to shift entries. If we only 2252 * had a single entry though we can just replace it and 2253 * be done. Otherwise walk the ring and shift the entries. 2254 */ 2255 WARN_ON_ONCE(last_sge == first_sge); 2256 shift = last_sge > first_sge ? 2257 last_sge - first_sge - 1 : 2258 MAX_SKB_FRAGS - first_sge + last_sge - 1; 2259 if (!shift) 2260 goto out; 2261 2262 i = first_sge; 2263 sk_msg_iter_var_next(i); 2264 do { 2265 u32 move_from; 2266 2267 if (i + shift >= MAX_MSG_FRAGS) 2268 move_from = i + shift - MAX_MSG_FRAGS; 2269 else 2270 move_from = i + shift; 2271 if (move_from == msg->sg.end) 2272 break; 2273 2274 msg->sg.data[i] = msg->sg.data[move_from]; 2275 msg->sg.data[move_from].length = 0; 2276 msg->sg.data[move_from].page_link = 0; 2277 msg->sg.data[move_from].offset = 0; 2278 sk_msg_iter_var_next(i); 2279 } while (1); 2280 2281 msg->sg.end = msg->sg.end - shift > msg->sg.end ? 2282 msg->sg.end - shift + MAX_MSG_FRAGS : 2283 msg->sg.end - shift; 2284 out: 2285 msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset; 2286 msg->data_end = msg->data + bytes; 2287 return 0; 2288 } 2289 2290 static const struct bpf_func_proto bpf_msg_pull_data_proto = { 2291 .func = bpf_msg_pull_data, 2292 .gpl_only = false, 2293 .ret_type = RET_INTEGER, 2294 .arg1_type = ARG_PTR_TO_CTX, 2295 .arg2_type = ARG_ANYTHING, 2296 .arg3_type = ARG_ANYTHING, 2297 .arg4_type = ARG_ANYTHING, 2298 }; 2299 2300 BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start, 2301 u32, len, u64, flags) 2302 { 2303 struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge; 2304 u32 new, i = 0, l, space, copy = 0, offset = 0; 2305 u8 *raw, *to, *from; 2306 struct page *page; 2307 2308 if (unlikely(flags)) 2309 return -EINVAL; 2310 2311 /* First find the starting scatterlist element */ 2312 i = msg->sg.start; 2313 do { 2314 l = sk_msg_elem(msg, i)->length; 2315 2316 if (start < offset + l) 2317 break; 2318 offset += l; 2319 sk_msg_iter_var_next(i); 2320 } while (i != msg->sg.end); 2321 2322 if (start >= offset + l) 2323 return -EINVAL; 2324 2325 space = MAX_MSG_FRAGS - sk_msg_elem_used(msg); 2326 2327 /* If no space available will fallback to copy, we need at 2328 * least one scatterlist elem available to push data into 2329 * when start aligns to the beginning of an element or two 2330 * when it falls inside an element. We handle the start equals 2331 * offset case because its the common case for inserting a 2332 * header. 2333 */ 2334 if (!space || (space == 1 && start != offset)) 2335 copy = msg->sg.data[i].length; 2336 2337 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP, 2338 get_order(copy + len)); 2339 if (unlikely(!page)) 2340 return -ENOMEM; 2341 2342 if (copy) { 2343 int front, back; 2344 2345 raw = page_address(page); 2346 2347 psge = sk_msg_elem(msg, i); 2348 front = start - offset; 2349 back = psge->length - front; 2350 from = sg_virt(psge); 2351 2352 if (front) 2353 memcpy(raw, from, front); 2354 2355 if (back) { 2356 from += front; 2357 to = raw + front + len; 2358 2359 memcpy(to, from, back); 2360 } 2361 2362 put_page(sg_page(psge)); 2363 } else if (start - offset) { 2364 psge = sk_msg_elem(msg, i); 2365 rsge = sk_msg_elem_cpy(msg, i); 2366 2367 psge->length = start - offset; 2368 rsge.length -= psge->length; 2369 rsge.offset += start; 2370 2371 sk_msg_iter_var_next(i); 2372 sg_unmark_end(psge); 2373 sk_msg_iter_next(msg, end); 2374 } 2375 2376 /* Slot(s) to place newly allocated data */ 2377 new = i; 2378 2379 /* Shift one or two slots as needed */ 2380 if (!copy) { 2381 sge = sk_msg_elem_cpy(msg, i); 2382 2383 sk_msg_iter_var_next(i); 2384 sg_unmark_end(&sge); 2385 sk_msg_iter_next(msg, end); 2386 2387 nsge = sk_msg_elem_cpy(msg, i); 2388 if (rsge.length) { 2389 sk_msg_iter_var_next(i); 2390 nnsge = sk_msg_elem_cpy(msg, i); 2391 } 2392 2393 while (i != msg->sg.end) { 2394 msg->sg.data[i] = sge; 2395 sge = nsge; 2396 sk_msg_iter_var_next(i); 2397 if (rsge.length) { 2398 nsge = nnsge; 2399 nnsge = sk_msg_elem_cpy(msg, i); 2400 } else { 2401 nsge = sk_msg_elem_cpy(msg, i); 2402 } 2403 } 2404 } 2405 2406 /* Place newly allocated data buffer */ 2407 sk_mem_charge(msg->sk, len); 2408 msg->sg.size += len; 2409 msg->sg.copy[new] = false; 2410 sg_set_page(&msg->sg.data[new], page, len + copy, 0); 2411 if (rsge.length) { 2412 get_page(sg_page(&rsge)); 2413 sk_msg_iter_var_next(new); 2414 msg->sg.data[new] = rsge; 2415 } 2416 2417 sk_msg_compute_data_pointers(msg); 2418 return 0; 2419 } 2420 2421 static const struct bpf_func_proto bpf_msg_push_data_proto = { 2422 .func = bpf_msg_push_data, 2423 .gpl_only = false, 2424 .ret_type = RET_INTEGER, 2425 .arg1_type = ARG_PTR_TO_CTX, 2426 .arg2_type = ARG_ANYTHING, 2427 .arg3_type = ARG_ANYTHING, 2428 .arg4_type = ARG_ANYTHING, 2429 }; 2430 2431 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb) 2432 { 2433 return task_get_classid(skb); 2434 } 2435 2436 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = { 2437 .func = bpf_get_cgroup_classid, 2438 .gpl_only = false, 2439 .ret_type = RET_INTEGER, 2440 .arg1_type = ARG_PTR_TO_CTX, 2441 }; 2442 2443 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb) 2444 { 2445 return dst_tclassid(skb); 2446 } 2447 2448 static const struct bpf_func_proto bpf_get_route_realm_proto = { 2449 .func = bpf_get_route_realm, 2450 .gpl_only = false, 2451 .ret_type = RET_INTEGER, 2452 .arg1_type = ARG_PTR_TO_CTX, 2453 }; 2454 2455 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb) 2456 { 2457 /* If skb_clear_hash() was called due to mangling, we can 2458 * trigger SW recalculation here. Later access to hash 2459 * can then use the inline skb->hash via context directly 2460 * instead of calling this helper again. 2461 */ 2462 return skb_get_hash(skb); 2463 } 2464 2465 static const struct bpf_func_proto bpf_get_hash_recalc_proto = { 2466 .func = bpf_get_hash_recalc, 2467 .gpl_only = false, 2468 .ret_type = RET_INTEGER, 2469 .arg1_type = ARG_PTR_TO_CTX, 2470 }; 2471 2472 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb) 2473 { 2474 /* After all direct packet write, this can be used once for 2475 * triggering a lazy recalc on next skb_get_hash() invocation. 2476 */ 2477 skb_clear_hash(skb); 2478 return 0; 2479 } 2480 2481 static const struct bpf_func_proto bpf_set_hash_invalid_proto = { 2482 .func = bpf_set_hash_invalid, 2483 .gpl_only = false, 2484 .ret_type = RET_INTEGER, 2485 .arg1_type = ARG_PTR_TO_CTX, 2486 }; 2487 2488 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash) 2489 { 2490 /* Set user specified hash as L4(+), so that it gets returned 2491 * on skb_get_hash() call unless BPF prog later on triggers a 2492 * skb_clear_hash(). 2493 */ 2494 __skb_set_sw_hash(skb, hash, true); 2495 return 0; 2496 } 2497 2498 static const struct bpf_func_proto bpf_set_hash_proto = { 2499 .func = bpf_set_hash, 2500 .gpl_only = false, 2501 .ret_type = RET_INTEGER, 2502 .arg1_type = ARG_PTR_TO_CTX, 2503 .arg2_type = ARG_ANYTHING, 2504 }; 2505 2506 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto, 2507 u16, vlan_tci) 2508 { 2509 int ret; 2510 2511 if (unlikely(vlan_proto != htons(ETH_P_8021Q) && 2512 vlan_proto != htons(ETH_P_8021AD))) 2513 vlan_proto = htons(ETH_P_8021Q); 2514 2515 bpf_push_mac_rcsum(skb); 2516 ret = skb_vlan_push(skb, vlan_proto, vlan_tci); 2517 bpf_pull_mac_rcsum(skb); 2518 2519 bpf_compute_data_pointers(skb); 2520 return ret; 2521 } 2522 2523 static const struct bpf_func_proto bpf_skb_vlan_push_proto = { 2524 .func = bpf_skb_vlan_push, 2525 .gpl_only = false, 2526 .ret_type = RET_INTEGER, 2527 .arg1_type = ARG_PTR_TO_CTX, 2528 .arg2_type = ARG_ANYTHING, 2529 .arg3_type = ARG_ANYTHING, 2530 }; 2531 2532 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb) 2533 { 2534 int ret; 2535 2536 bpf_push_mac_rcsum(skb); 2537 ret = skb_vlan_pop(skb); 2538 bpf_pull_mac_rcsum(skb); 2539 2540 bpf_compute_data_pointers(skb); 2541 return ret; 2542 } 2543 2544 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = { 2545 .func = bpf_skb_vlan_pop, 2546 .gpl_only = false, 2547 .ret_type = RET_INTEGER, 2548 .arg1_type = ARG_PTR_TO_CTX, 2549 }; 2550 2551 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len) 2552 { 2553 /* Caller already did skb_cow() with len as headroom, 2554 * so no need to do it here. 2555 */ 2556 skb_push(skb, len); 2557 memmove(skb->data, skb->data + len, off); 2558 memset(skb->data + off, 0, len); 2559 2560 /* No skb_postpush_rcsum(skb, skb->data + off, len) 2561 * needed here as it does not change the skb->csum 2562 * result for checksum complete when summing over 2563 * zeroed blocks. 2564 */ 2565 return 0; 2566 } 2567 2568 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len) 2569 { 2570 /* skb_ensure_writable() is not needed here, as we're 2571 * already working on an uncloned skb. 2572 */ 2573 if (unlikely(!pskb_may_pull(skb, off + len))) 2574 return -ENOMEM; 2575 2576 skb_postpull_rcsum(skb, skb->data + off, len); 2577 memmove(skb->data + len, skb->data, off); 2578 __skb_pull(skb, len); 2579 2580 return 0; 2581 } 2582 2583 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len) 2584 { 2585 bool trans_same = skb->transport_header == skb->network_header; 2586 int ret; 2587 2588 /* There's no need for __skb_push()/__skb_pull() pair to 2589 * get to the start of the mac header as we're guaranteed 2590 * to always start from here under eBPF. 2591 */ 2592 ret = bpf_skb_generic_push(skb, off, len); 2593 if (likely(!ret)) { 2594 skb->mac_header -= len; 2595 skb->network_header -= len; 2596 if (trans_same) 2597 skb->transport_header = skb->network_header; 2598 } 2599 2600 return ret; 2601 } 2602 2603 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len) 2604 { 2605 bool trans_same = skb->transport_header == skb->network_header; 2606 int ret; 2607 2608 /* Same here, __skb_push()/__skb_pull() pair not needed. */ 2609 ret = bpf_skb_generic_pop(skb, off, len); 2610 if (likely(!ret)) { 2611 skb->mac_header += len; 2612 skb->network_header += len; 2613 if (trans_same) 2614 skb->transport_header = skb->network_header; 2615 } 2616 2617 return ret; 2618 } 2619 2620 static int bpf_skb_proto_4_to_6(struct sk_buff *skb) 2621 { 2622 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); 2623 u32 off = skb_mac_header_len(skb); 2624 int ret; 2625 2626 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2627 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2628 return -ENOTSUPP; 2629 2630 ret = skb_cow(skb, len_diff); 2631 if (unlikely(ret < 0)) 2632 return ret; 2633 2634 ret = bpf_skb_net_hdr_push(skb, off, len_diff); 2635 if (unlikely(ret < 0)) 2636 return ret; 2637 2638 if (skb_is_gso(skb)) { 2639 struct skb_shared_info *shinfo = skb_shinfo(skb); 2640 2641 /* SKB_GSO_TCPV4 needs to be changed into 2642 * SKB_GSO_TCPV6. 2643 */ 2644 if (shinfo->gso_type & SKB_GSO_TCPV4) { 2645 shinfo->gso_type &= ~SKB_GSO_TCPV4; 2646 shinfo->gso_type |= SKB_GSO_TCPV6; 2647 } 2648 2649 /* Due to IPv6 header, MSS needs to be downgraded. */ 2650 skb_decrease_gso_size(shinfo, len_diff); 2651 /* Header must be checked, and gso_segs recomputed. */ 2652 shinfo->gso_type |= SKB_GSO_DODGY; 2653 shinfo->gso_segs = 0; 2654 } 2655 2656 skb->protocol = htons(ETH_P_IPV6); 2657 skb_clear_hash(skb); 2658 2659 return 0; 2660 } 2661 2662 static int bpf_skb_proto_6_to_4(struct sk_buff *skb) 2663 { 2664 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); 2665 u32 off = skb_mac_header_len(skb); 2666 int ret; 2667 2668 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2669 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2670 return -ENOTSUPP; 2671 2672 ret = skb_unclone(skb, GFP_ATOMIC); 2673 if (unlikely(ret < 0)) 2674 return ret; 2675 2676 ret = bpf_skb_net_hdr_pop(skb, off, len_diff); 2677 if (unlikely(ret < 0)) 2678 return ret; 2679 2680 if (skb_is_gso(skb)) { 2681 struct skb_shared_info *shinfo = skb_shinfo(skb); 2682 2683 /* SKB_GSO_TCPV6 needs to be changed into 2684 * SKB_GSO_TCPV4. 2685 */ 2686 if (shinfo->gso_type & SKB_GSO_TCPV6) { 2687 shinfo->gso_type &= ~SKB_GSO_TCPV6; 2688 shinfo->gso_type |= SKB_GSO_TCPV4; 2689 } 2690 2691 /* Due to IPv4 header, MSS can be upgraded. */ 2692 skb_increase_gso_size(shinfo, len_diff); 2693 /* Header must be checked, and gso_segs recomputed. */ 2694 shinfo->gso_type |= SKB_GSO_DODGY; 2695 shinfo->gso_segs = 0; 2696 } 2697 2698 skb->protocol = htons(ETH_P_IP); 2699 skb_clear_hash(skb); 2700 2701 return 0; 2702 } 2703 2704 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto) 2705 { 2706 __be16 from_proto = skb->protocol; 2707 2708 if (from_proto == htons(ETH_P_IP) && 2709 to_proto == htons(ETH_P_IPV6)) 2710 return bpf_skb_proto_4_to_6(skb); 2711 2712 if (from_proto == htons(ETH_P_IPV6) && 2713 to_proto == htons(ETH_P_IP)) 2714 return bpf_skb_proto_6_to_4(skb); 2715 2716 return -ENOTSUPP; 2717 } 2718 2719 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto, 2720 u64, flags) 2721 { 2722 int ret; 2723 2724 if (unlikely(flags)) 2725 return -EINVAL; 2726 2727 /* General idea is that this helper does the basic groundwork 2728 * needed for changing the protocol, and eBPF program fills the 2729 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace() 2730 * and other helpers, rather than passing a raw buffer here. 2731 * 2732 * The rationale is to keep this minimal and without a need to 2733 * deal with raw packet data. F.e. even if we would pass buffers 2734 * here, the program still needs to call the bpf_lX_csum_replace() 2735 * helpers anyway. Plus, this way we keep also separation of 2736 * concerns, since f.e. bpf_skb_store_bytes() should only take 2737 * care of stores. 2738 * 2739 * Currently, additional options and extension header space are 2740 * not supported, but flags register is reserved so we can adapt 2741 * that. For offloads, we mark packet as dodgy, so that headers 2742 * need to be verified first. 2743 */ 2744 ret = bpf_skb_proto_xlat(skb, proto); 2745 bpf_compute_data_pointers(skb); 2746 return ret; 2747 } 2748 2749 static const struct bpf_func_proto bpf_skb_change_proto_proto = { 2750 .func = bpf_skb_change_proto, 2751 .gpl_only = false, 2752 .ret_type = RET_INTEGER, 2753 .arg1_type = ARG_PTR_TO_CTX, 2754 .arg2_type = ARG_ANYTHING, 2755 .arg3_type = ARG_ANYTHING, 2756 }; 2757 2758 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type) 2759 { 2760 /* We only allow a restricted subset to be changed for now. */ 2761 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) || 2762 !skb_pkt_type_ok(pkt_type))) 2763 return -EINVAL; 2764 2765 skb->pkt_type = pkt_type; 2766 return 0; 2767 } 2768 2769 static const struct bpf_func_proto bpf_skb_change_type_proto = { 2770 .func = bpf_skb_change_type, 2771 .gpl_only = false, 2772 .ret_type = RET_INTEGER, 2773 .arg1_type = ARG_PTR_TO_CTX, 2774 .arg2_type = ARG_ANYTHING, 2775 }; 2776 2777 static u32 bpf_skb_net_base_len(const struct sk_buff *skb) 2778 { 2779 switch (skb->protocol) { 2780 case htons(ETH_P_IP): 2781 return sizeof(struct iphdr); 2782 case htons(ETH_P_IPV6): 2783 return sizeof(struct ipv6hdr); 2784 default: 2785 return ~0U; 2786 } 2787 } 2788 2789 static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff) 2790 { 2791 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); 2792 int ret; 2793 2794 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2795 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2796 return -ENOTSUPP; 2797 2798 ret = skb_cow(skb, len_diff); 2799 if (unlikely(ret < 0)) 2800 return ret; 2801 2802 ret = bpf_skb_net_hdr_push(skb, off, len_diff); 2803 if (unlikely(ret < 0)) 2804 return ret; 2805 2806 if (skb_is_gso(skb)) { 2807 struct skb_shared_info *shinfo = skb_shinfo(skb); 2808 2809 /* Due to header grow, MSS needs to be downgraded. */ 2810 skb_decrease_gso_size(shinfo, len_diff); 2811 /* Header must be checked, and gso_segs recomputed. */ 2812 shinfo->gso_type |= SKB_GSO_DODGY; 2813 shinfo->gso_segs = 0; 2814 } 2815 2816 return 0; 2817 } 2818 2819 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff) 2820 { 2821 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); 2822 int ret; 2823 2824 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2825 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2826 return -ENOTSUPP; 2827 2828 ret = skb_unclone(skb, GFP_ATOMIC); 2829 if (unlikely(ret < 0)) 2830 return ret; 2831 2832 ret = bpf_skb_net_hdr_pop(skb, off, len_diff); 2833 if (unlikely(ret < 0)) 2834 return ret; 2835 2836 if (skb_is_gso(skb)) { 2837 struct skb_shared_info *shinfo = skb_shinfo(skb); 2838 2839 /* Due to header shrink, MSS can be upgraded. */ 2840 skb_increase_gso_size(shinfo, len_diff); 2841 /* Header must be checked, and gso_segs recomputed. */ 2842 shinfo->gso_type |= SKB_GSO_DODGY; 2843 shinfo->gso_segs = 0; 2844 } 2845 2846 return 0; 2847 } 2848 2849 static u32 __bpf_skb_max_len(const struct sk_buff *skb) 2850 { 2851 return skb->dev ? skb->dev->mtu + skb->dev->hard_header_len : 2852 SKB_MAX_ALLOC; 2853 } 2854 2855 static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff) 2856 { 2857 bool trans_same = skb->transport_header == skb->network_header; 2858 u32 len_cur, len_diff_abs = abs(len_diff); 2859 u32 len_min = bpf_skb_net_base_len(skb); 2860 u32 len_max = __bpf_skb_max_len(skb); 2861 __be16 proto = skb->protocol; 2862 bool shrink = len_diff < 0; 2863 int ret; 2864 2865 if (unlikely(len_diff_abs > 0xfffU)) 2866 return -EFAULT; 2867 if (unlikely(proto != htons(ETH_P_IP) && 2868 proto != htons(ETH_P_IPV6))) 2869 return -ENOTSUPP; 2870 2871 len_cur = skb->len - skb_network_offset(skb); 2872 if (skb_transport_header_was_set(skb) && !trans_same) 2873 len_cur = skb_network_header_len(skb); 2874 if ((shrink && (len_diff_abs >= len_cur || 2875 len_cur - len_diff_abs < len_min)) || 2876 (!shrink && (skb->len + len_diff_abs > len_max && 2877 !skb_is_gso(skb)))) 2878 return -ENOTSUPP; 2879 2880 ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) : 2881 bpf_skb_net_grow(skb, len_diff_abs); 2882 2883 bpf_compute_data_pointers(skb); 2884 return ret; 2885 } 2886 2887 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff, 2888 u32, mode, u64, flags) 2889 { 2890 if (unlikely(flags)) 2891 return -EINVAL; 2892 if (likely(mode == BPF_ADJ_ROOM_NET)) 2893 return bpf_skb_adjust_net(skb, len_diff); 2894 2895 return -ENOTSUPP; 2896 } 2897 2898 static const struct bpf_func_proto bpf_skb_adjust_room_proto = { 2899 .func = bpf_skb_adjust_room, 2900 .gpl_only = false, 2901 .ret_type = RET_INTEGER, 2902 .arg1_type = ARG_PTR_TO_CTX, 2903 .arg2_type = ARG_ANYTHING, 2904 .arg3_type = ARG_ANYTHING, 2905 .arg4_type = ARG_ANYTHING, 2906 }; 2907 2908 static u32 __bpf_skb_min_len(const struct sk_buff *skb) 2909 { 2910 u32 min_len = skb_network_offset(skb); 2911 2912 if (skb_transport_header_was_set(skb)) 2913 min_len = skb_transport_offset(skb); 2914 if (skb->ip_summed == CHECKSUM_PARTIAL) 2915 min_len = skb_checksum_start_offset(skb) + 2916 skb->csum_offset + sizeof(__sum16); 2917 return min_len; 2918 } 2919 2920 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len) 2921 { 2922 unsigned int old_len = skb->len; 2923 int ret; 2924 2925 ret = __skb_grow_rcsum(skb, new_len); 2926 if (!ret) 2927 memset(skb->data + old_len, 0, new_len - old_len); 2928 return ret; 2929 } 2930 2931 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len) 2932 { 2933 return __skb_trim_rcsum(skb, new_len); 2934 } 2935 2936 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len, 2937 u64 flags) 2938 { 2939 u32 max_len = __bpf_skb_max_len(skb); 2940 u32 min_len = __bpf_skb_min_len(skb); 2941 int ret; 2942 2943 if (unlikely(flags || new_len > max_len || new_len < min_len)) 2944 return -EINVAL; 2945 if (skb->encapsulation) 2946 return -ENOTSUPP; 2947 2948 /* The basic idea of this helper is that it's performing the 2949 * needed work to either grow or trim an skb, and eBPF program 2950 * rewrites the rest via helpers like bpf_skb_store_bytes(), 2951 * bpf_lX_csum_replace() and others rather than passing a raw 2952 * buffer here. This one is a slow path helper and intended 2953 * for replies with control messages. 2954 * 2955 * Like in bpf_skb_change_proto(), we want to keep this rather 2956 * minimal and without protocol specifics so that we are able 2957 * to separate concerns as in bpf_skb_store_bytes() should only 2958 * be the one responsible for writing buffers. 2959 * 2960 * It's really expected to be a slow path operation here for 2961 * control message replies, so we're implicitly linearizing, 2962 * uncloning and drop offloads from the skb by this. 2963 */ 2964 ret = __bpf_try_make_writable(skb, skb->len); 2965 if (!ret) { 2966 if (new_len > skb->len) 2967 ret = bpf_skb_grow_rcsum(skb, new_len); 2968 else if (new_len < skb->len) 2969 ret = bpf_skb_trim_rcsum(skb, new_len); 2970 if (!ret && skb_is_gso(skb)) 2971 skb_gso_reset(skb); 2972 } 2973 return ret; 2974 } 2975 2976 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len, 2977 u64, flags) 2978 { 2979 int ret = __bpf_skb_change_tail(skb, new_len, flags); 2980 2981 bpf_compute_data_pointers(skb); 2982 return ret; 2983 } 2984 2985 static const struct bpf_func_proto bpf_skb_change_tail_proto = { 2986 .func = bpf_skb_change_tail, 2987 .gpl_only = false, 2988 .ret_type = RET_INTEGER, 2989 .arg1_type = ARG_PTR_TO_CTX, 2990 .arg2_type = ARG_ANYTHING, 2991 .arg3_type = ARG_ANYTHING, 2992 }; 2993 2994 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len, 2995 u64, flags) 2996 { 2997 int ret = __bpf_skb_change_tail(skb, new_len, flags); 2998 2999 bpf_compute_data_end_sk_skb(skb); 3000 return ret; 3001 } 3002 3003 static const struct bpf_func_proto sk_skb_change_tail_proto = { 3004 .func = sk_skb_change_tail, 3005 .gpl_only = false, 3006 .ret_type = RET_INTEGER, 3007 .arg1_type = ARG_PTR_TO_CTX, 3008 .arg2_type = ARG_ANYTHING, 3009 .arg3_type = ARG_ANYTHING, 3010 }; 3011 3012 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room, 3013 u64 flags) 3014 { 3015 u32 max_len = __bpf_skb_max_len(skb); 3016 u32 new_len = skb->len + head_room; 3017 int ret; 3018 3019 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) || 3020 new_len < skb->len)) 3021 return -EINVAL; 3022 3023 ret = skb_cow(skb, head_room); 3024 if (likely(!ret)) { 3025 /* Idea for this helper is that we currently only 3026 * allow to expand on mac header. This means that 3027 * skb->protocol network header, etc, stay as is. 3028 * Compared to bpf_skb_change_tail(), we're more 3029 * flexible due to not needing to linearize or 3030 * reset GSO. Intention for this helper is to be 3031 * used by an L3 skb that needs to push mac header 3032 * for redirection into L2 device. 3033 */ 3034 __skb_push(skb, head_room); 3035 memset(skb->data, 0, head_room); 3036 skb_reset_mac_header(skb); 3037 } 3038 3039 return ret; 3040 } 3041 3042 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room, 3043 u64, flags) 3044 { 3045 int ret = __bpf_skb_change_head(skb, head_room, flags); 3046 3047 bpf_compute_data_pointers(skb); 3048 return ret; 3049 } 3050 3051 static const struct bpf_func_proto bpf_skb_change_head_proto = { 3052 .func = bpf_skb_change_head, 3053 .gpl_only = false, 3054 .ret_type = RET_INTEGER, 3055 .arg1_type = ARG_PTR_TO_CTX, 3056 .arg2_type = ARG_ANYTHING, 3057 .arg3_type = ARG_ANYTHING, 3058 }; 3059 3060 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room, 3061 u64, flags) 3062 { 3063 int ret = __bpf_skb_change_head(skb, head_room, flags); 3064 3065 bpf_compute_data_end_sk_skb(skb); 3066 return ret; 3067 } 3068 3069 static const struct bpf_func_proto sk_skb_change_head_proto = { 3070 .func = sk_skb_change_head, 3071 .gpl_only = false, 3072 .ret_type = RET_INTEGER, 3073 .arg1_type = ARG_PTR_TO_CTX, 3074 .arg2_type = ARG_ANYTHING, 3075 .arg3_type = ARG_ANYTHING, 3076 }; 3077 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp) 3078 { 3079 return xdp_data_meta_unsupported(xdp) ? 0 : 3080 xdp->data - xdp->data_meta; 3081 } 3082 3083 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset) 3084 { 3085 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); 3086 unsigned long metalen = xdp_get_metalen(xdp); 3087 void *data_start = xdp_frame_end + metalen; 3088 void *data = xdp->data + offset; 3089 3090 if (unlikely(data < data_start || 3091 data > xdp->data_end - ETH_HLEN)) 3092 return -EINVAL; 3093 3094 if (metalen) 3095 memmove(xdp->data_meta + offset, 3096 xdp->data_meta, metalen); 3097 xdp->data_meta += offset; 3098 xdp->data = data; 3099 3100 return 0; 3101 } 3102 3103 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = { 3104 .func = bpf_xdp_adjust_head, 3105 .gpl_only = false, 3106 .ret_type = RET_INTEGER, 3107 .arg1_type = ARG_PTR_TO_CTX, 3108 .arg2_type = ARG_ANYTHING, 3109 }; 3110 3111 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset) 3112 { 3113 void *data_end = xdp->data_end + offset; 3114 3115 /* only shrinking is allowed for now. */ 3116 if (unlikely(offset >= 0)) 3117 return -EINVAL; 3118 3119 if (unlikely(data_end < xdp->data + ETH_HLEN)) 3120 return -EINVAL; 3121 3122 xdp->data_end = data_end; 3123 3124 return 0; 3125 } 3126 3127 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = { 3128 .func = bpf_xdp_adjust_tail, 3129 .gpl_only = false, 3130 .ret_type = RET_INTEGER, 3131 .arg1_type = ARG_PTR_TO_CTX, 3132 .arg2_type = ARG_ANYTHING, 3133 }; 3134 3135 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset) 3136 { 3137 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); 3138 void *meta = xdp->data_meta + offset; 3139 unsigned long metalen = xdp->data - meta; 3140 3141 if (xdp_data_meta_unsupported(xdp)) 3142 return -ENOTSUPP; 3143 if (unlikely(meta < xdp_frame_end || 3144 meta > xdp->data)) 3145 return -EINVAL; 3146 if (unlikely((metalen & (sizeof(__u32) - 1)) || 3147 (metalen > 32))) 3148 return -EACCES; 3149 3150 xdp->data_meta = meta; 3151 3152 return 0; 3153 } 3154 3155 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = { 3156 .func = bpf_xdp_adjust_meta, 3157 .gpl_only = false, 3158 .ret_type = RET_INTEGER, 3159 .arg1_type = ARG_PTR_TO_CTX, 3160 .arg2_type = ARG_ANYTHING, 3161 }; 3162 3163 static int __bpf_tx_xdp(struct net_device *dev, 3164 struct bpf_map *map, 3165 struct xdp_buff *xdp, 3166 u32 index) 3167 { 3168 struct xdp_frame *xdpf; 3169 int err, sent; 3170 3171 if (!dev->netdev_ops->ndo_xdp_xmit) { 3172 return -EOPNOTSUPP; 3173 } 3174 3175 err = xdp_ok_fwd_dev(dev, xdp->data_end - xdp->data); 3176 if (unlikely(err)) 3177 return err; 3178 3179 xdpf = convert_to_xdp_frame(xdp); 3180 if (unlikely(!xdpf)) 3181 return -EOVERFLOW; 3182 3183 sent = dev->netdev_ops->ndo_xdp_xmit(dev, 1, &xdpf, XDP_XMIT_FLUSH); 3184 if (sent <= 0) 3185 return sent; 3186 return 0; 3187 } 3188 3189 static noinline int 3190 xdp_do_redirect_slow(struct net_device *dev, struct xdp_buff *xdp, 3191 struct bpf_prog *xdp_prog, struct bpf_redirect_info *ri) 3192 { 3193 struct net_device *fwd; 3194 u32 index = ri->ifindex; 3195 int err; 3196 3197 fwd = dev_get_by_index_rcu(dev_net(dev), index); 3198 ri->ifindex = 0; 3199 if (unlikely(!fwd)) { 3200 err = -EINVAL; 3201 goto err; 3202 } 3203 3204 err = __bpf_tx_xdp(fwd, NULL, xdp, 0); 3205 if (unlikely(err)) 3206 goto err; 3207 3208 _trace_xdp_redirect(dev, xdp_prog, index); 3209 return 0; 3210 err: 3211 _trace_xdp_redirect_err(dev, xdp_prog, index, err); 3212 return err; 3213 } 3214 3215 static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, 3216 struct bpf_map *map, 3217 struct xdp_buff *xdp, 3218 u32 index) 3219 { 3220 int err; 3221 3222 switch (map->map_type) { 3223 case BPF_MAP_TYPE_DEVMAP: { 3224 struct bpf_dtab_netdev *dst = fwd; 3225 3226 err = dev_map_enqueue(dst, xdp, dev_rx); 3227 if (unlikely(err)) 3228 return err; 3229 __dev_map_insert_ctx(map, index); 3230 break; 3231 } 3232 case BPF_MAP_TYPE_CPUMAP: { 3233 struct bpf_cpu_map_entry *rcpu = fwd; 3234 3235 err = cpu_map_enqueue(rcpu, xdp, dev_rx); 3236 if (unlikely(err)) 3237 return err; 3238 __cpu_map_insert_ctx(map, index); 3239 break; 3240 } 3241 case BPF_MAP_TYPE_XSKMAP: { 3242 struct xdp_sock *xs = fwd; 3243 3244 err = __xsk_map_redirect(map, xdp, xs); 3245 return err; 3246 } 3247 default: 3248 break; 3249 } 3250 return 0; 3251 } 3252 3253 void xdp_do_flush_map(void) 3254 { 3255 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 3256 struct bpf_map *map = ri->map_to_flush; 3257 3258 ri->map_to_flush = NULL; 3259 if (map) { 3260 switch (map->map_type) { 3261 case BPF_MAP_TYPE_DEVMAP: 3262 __dev_map_flush(map); 3263 break; 3264 case BPF_MAP_TYPE_CPUMAP: 3265 __cpu_map_flush(map); 3266 break; 3267 case BPF_MAP_TYPE_XSKMAP: 3268 __xsk_map_flush(map); 3269 break; 3270 default: 3271 break; 3272 } 3273 } 3274 } 3275 EXPORT_SYMBOL_GPL(xdp_do_flush_map); 3276 3277 static inline void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index) 3278 { 3279 switch (map->map_type) { 3280 case BPF_MAP_TYPE_DEVMAP: 3281 return __dev_map_lookup_elem(map, index); 3282 case BPF_MAP_TYPE_CPUMAP: 3283 return __cpu_map_lookup_elem(map, index); 3284 case BPF_MAP_TYPE_XSKMAP: 3285 return __xsk_map_lookup_elem(map, index); 3286 default: 3287 return NULL; 3288 } 3289 } 3290 3291 void bpf_clear_redirect_map(struct bpf_map *map) 3292 { 3293 struct bpf_redirect_info *ri; 3294 int cpu; 3295 3296 for_each_possible_cpu(cpu) { 3297 ri = per_cpu_ptr(&bpf_redirect_info, cpu); 3298 /* Avoid polluting remote cacheline due to writes if 3299 * not needed. Once we pass this test, we need the 3300 * cmpxchg() to make sure it hasn't been changed in 3301 * the meantime by remote CPU. 3302 */ 3303 if (unlikely(READ_ONCE(ri->map) == map)) 3304 cmpxchg(&ri->map, map, NULL); 3305 } 3306 } 3307 3308 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, 3309 struct bpf_prog *xdp_prog, struct bpf_map *map, 3310 struct bpf_redirect_info *ri) 3311 { 3312 u32 index = ri->ifindex; 3313 void *fwd = NULL; 3314 int err; 3315 3316 ri->ifindex = 0; 3317 WRITE_ONCE(ri->map, NULL); 3318 3319 fwd = __xdp_map_lookup_elem(map, index); 3320 if (unlikely(!fwd)) { 3321 err = -EINVAL; 3322 goto err; 3323 } 3324 if (ri->map_to_flush && unlikely(ri->map_to_flush != map)) 3325 xdp_do_flush_map(); 3326 3327 err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index); 3328 if (unlikely(err)) 3329 goto err; 3330 3331 ri->map_to_flush = map; 3332 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); 3333 return 0; 3334 err: 3335 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); 3336 return err; 3337 } 3338 3339 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, 3340 struct bpf_prog *xdp_prog) 3341 { 3342 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 3343 struct bpf_map *map = READ_ONCE(ri->map); 3344 3345 if (likely(map)) 3346 return xdp_do_redirect_map(dev, xdp, xdp_prog, map, ri); 3347 3348 return xdp_do_redirect_slow(dev, xdp, xdp_prog, ri); 3349 } 3350 EXPORT_SYMBOL_GPL(xdp_do_redirect); 3351 3352 static int xdp_do_generic_redirect_map(struct net_device *dev, 3353 struct sk_buff *skb, 3354 struct xdp_buff *xdp, 3355 struct bpf_prog *xdp_prog, 3356 struct bpf_map *map) 3357 { 3358 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 3359 u32 index = ri->ifindex; 3360 void *fwd = NULL; 3361 int err = 0; 3362 3363 ri->ifindex = 0; 3364 WRITE_ONCE(ri->map, NULL); 3365 3366 fwd = __xdp_map_lookup_elem(map, index); 3367 if (unlikely(!fwd)) { 3368 err = -EINVAL; 3369 goto err; 3370 } 3371 3372 if (map->map_type == BPF_MAP_TYPE_DEVMAP) { 3373 struct bpf_dtab_netdev *dst = fwd; 3374 3375 err = dev_map_generic_redirect(dst, skb, xdp_prog); 3376 if (unlikely(err)) 3377 goto err; 3378 } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) { 3379 struct xdp_sock *xs = fwd; 3380 3381 err = xsk_generic_rcv(xs, xdp); 3382 if (err) 3383 goto err; 3384 consume_skb(skb); 3385 } else { 3386 /* TODO: Handle BPF_MAP_TYPE_CPUMAP */ 3387 err = -EBADRQC; 3388 goto err; 3389 } 3390 3391 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); 3392 return 0; 3393 err: 3394 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); 3395 return err; 3396 } 3397 3398 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, 3399 struct xdp_buff *xdp, struct bpf_prog *xdp_prog) 3400 { 3401 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 3402 struct bpf_map *map = READ_ONCE(ri->map); 3403 u32 index = ri->ifindex; 3404 struct net_device *fwd; 3405 int err = 0; 3406 3407 if (map) 3408 return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, 3409 map); 3410 ri->ifindex = 0; 3411 fwd = dev_get_by_index_rcu(dev_net(dev), index); 3412 if (unlikely(!fwd)) { 3413 err = -EINVAL; 3414 goto err; 3415 } 3416 3417 err = xdp_ok_fwd_dev(fwd, skb->len); 3418 if (unlikely(err)) 3419 goto err; 3420 3421 skb->dev = fwd; 3422 _trace_xdp_redirect(dev, xdp_prog, index); 3423 generic_xdp_tx(skb, xdp_prog); 3424 return 0; 3425 err: 3426 _trace_xdp_redirect_err(dev, xdp_prog, index, err); 3427 return err; 3428 } 3429 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect); 3430 3431 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags) 3432 { 3433 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 3434 3435 if (unlikely(flags)) 3436 return XDP_ABORTED; 3437 3438 ri->ifindex = ifindex; 3439 ri->flags = flags; 3440 WRITE_ONCE(ri->map, NULL); 3441 3442 return XDP_REDIRECT; 3443 } 3444 3445 static const struct bpf_func_proto bpf_xdp_redirect_proto = { 3446 .func = bpf_xdp_redirect, 3447 .gpl_only = false, 3448 .ret_type = RET_INTEGER, 3449 .arg1_type = ARG_ANYTHING, 3450 .arg2_type = ARG_ANYTHING, 3451 }; 3452 3453 BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, 3454 u64, flags) 3455 { 3456 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); 3457 3458 if (unlikely(flags)) 3459 return XDP_ABORTED; 3460 3461 ri->ifindex = ifindex; 3462 ri->flags = flags; 3463 WRITE_ONCE(ri->map, map); 3464 3465 return XDP_REDIRECT; 3466 } 3467 3468 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = { 3469 .func = bpf_xdp_redirect_map, 3470 .gpl_only = false, 3471 .ret_type = RET_INTEGER, 3472 .arg1_type = ARG_CONST_MAP_PTR, 3473 .arg2_type = ARG_ANYTHING, 3474 .arg3_type = ARG_ANYTHING, 3475 }; 3476 3477 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb, 3478 unsigned long off, unsigned long len) 3479 { 3480 void *ptr = skb_header_pointer(skb, off, len, dst_buff); 3481 3482 if (unlikely(!ptr)) 3483 return len; 3484 if (ptr != dst_buff) 3485 memcpy(dst_buff, ptr, len); 3486 3487 return 0; 3488 } 3489 3490 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map, 3491 u64, flags, void *, meta, u64, meta_size) 3492 { 3493 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32; 3494 3495 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) 3496 return -EINVAL; 3497 if (unlikely(skb_size > skb->len)) 3498 return -EFAULT; 3499 3500 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size, 3501 bpf_skb_copy); 3502 } 3503 3504 static const struct bpf_func_proto bpf_skb_event_output_proto = { 3505 .func = bpf_skb_event_output, 3506 .gpl_only = true, 3507 .ret_type = RET_INTEGER, 3508 .arg1_type = ARG_PTR_TO_CTX, 3509 .arg2_type = ARG_CONST_MAP_PTR, 3510 .arg3_type = ARG_ANYTHING, 3511 .arg4_type = ARG_PTR_TO_MEM, 3512 .arg5_type = ARG_CONST_SIZE_OR_ZERO, 3513 }; 3514 3515 static unsigned short bpf_tunnel_key_af(u64 flags) 3516 { 3517 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET; 3518 } 3519 3520 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to, 3521 u32, size, u64, flags) 3522 { 3523 const struct ip_tunnel_info *info = skb_tunnel_info(skb); 3524 u8 compat[sizeof(struct bpf_tunnel_key)]; 3525 void *to_orig = to; 3526 int err; 3527 3528 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) { 3529 err = -EINVAL; 3530 goto err_clear; 3531 } 3532 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) { 3533 err = -EPROTO; 3534 goto err_clear; 3535 } 3536 if (unlikely(size != sizeof(struct bpf_tunnel_key))) { 3537 err = -EINVAL; 3538 switch (size) { 3539 case offsetof(struct bpf_tunnel_key, tunnel_label): 3540 case offsetof(struct bpf_tunnel_key, tunnel_ext): 3541 goto set_compat; 3542 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): 3543 /* Fixup deprecated structure layouts here, so we have 3544 * a common path later on. 3545 */ 3546 if (ip_tunnel_info_af(info) != AF_INET) 3547 goto err_clear; 3548 set_compat: 3549 to = (struct bpf_tunnel_key *)compat; 3550 break; 3551 default: 3552 goto err_clear; 3553 } 3554 } 3555 3556 to->tunnel_id = be64_to_cpu(info->key.tun_id); 3557 to->tunnel_tos = info->key.tos; 3558 to->tunnel_ttl = info->key.ttl; 3559 to->tunnel_ext = 0; 3560 3561 if (flags & BPF_F_TUNINFO_IPV6) { 3562 memcpy(to->remote_ipv6, &info->key.u.ipv6.src, 3563 sizeof(to->remote_ipv6)); 3564 to->tunnel_label = be32_to_cpu(info->key.label); 3565 } else { 3566 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src); 3567 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3); 3568 to->tunnel_label = 0; 3569 } 3570 3571 if (unlikely(size != sizeof(struct bpf_tunnel_key))) 3572 memcpy(to_orig, to, size); 3573 3574 return 0; 3575 err_clear: 3576 memset(to_orig, 0, size); 3577 return err; 3578 } 3579 3580 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = { 3581 .func = bpf_skb_get_tunnel_key, 3582 .gpl_only = false, 3583 .ret_type = RET_INTEGER, 3584 .arg1_type = ARG_PTR_TO_CTX, 3585 .arg2_type = ARG_PTR_TO_UNINIT_MEM, 3586 .arg3_type = ARG_CONST_SIZE, 3587 .arg4_type = ARG_ANYTHING, 3588 }; 3589 3590 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size) 3591 { 3592 const struct ip_tunnel_info *info = skb_tunnel_info(skb); 3593 int err; 3594 3595 if (unlikely(!info || 3596 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) { 3597 err = -ENOENT; 3598 goto err_clear; 3599 } 3600 if (unlikely(size < info->options_len)) { 3601 err = -ENOMEM; 3602 goto err_clear; 3603 } 3604 3605 ip_tunnel_info_opts_get(to, info); 3606 if (size > info->options_len) 3607 memset(to + info->options_len, 0, size - info->options_len); 3608 3609 return info->options_len; 3610 err_clear: 3611 memset(to, 0, size); 3612 return err; 3613 } 3614 3615 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = { 3616 .func = bpf_skb_get_tunnel_opt, 3617 .gpl_only = false, 3618 .ret_type = RET_INTEGER, 3619 .arg1_type = ARG_PTR_TO_CTX, 3620 .arg2_type = ARG_PTR_TO_UNINIT_MEM, 3621 .arg3_type = ARG_CONST_SIZE, 3622 }; 3623 3624 static struct metadata_dst __percpu *md_dst; 3625 3626 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb, 3627 const struct bpf_tunnel_key *, from, u32, size, u64, flags) 3628 { 3629 struct metadata_dst *md = this_cpu_ptr(md_dst); 3630 u8 compat[sizeof(struct bpf_tunnel_key)]; 3631 struct ip_tunnel_info *info; 3632 3633 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX | 3634 BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER))) 3635 return -EINVAL; 3636 if (unlikely(size != sizeof(struct bpf_tunnel_key))) { 3637 switch (size) { 3638 case offsetof(struct bpf_tunnel_key, tunnel_label): 3639 case offsetof(struct bpf_tunnel_key, tunnel_ext): 3640 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): 3641 /* Fixup deprecated structure layouts here, so we have 3642 * a common path later on. 3643 */ 3644 memcpy(compat, from, size); 3645 memset(compat + size, 0, sizeof(compat) - size); 3646 from = (const struct bpf_tunnel_key *) compat; 3647 break; 3648 default: 3649 return -EINVAL; 3650 } 3651 } 3652 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) || 3653 from->tunnel_ext)) 3654 return -EINVAL; 3655 3656 skb_dst_drop(skb); 3657 dst_hold((struct dst_entry *) md); 3658 skb_dst_set(skb, (struct dst_entry *) md); 3659 3660 info = &md->u.tun_info; 3661 memset(info, 0, sizeof(*info)); 3662 info->mode = IP_TUNNEL_INFO_TX; 3663 3664 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE; 3665 if (flags & BPF_F_DONT_FRAGMENT) 3666 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT; 3667 if (flags & BPF_F_ZERO_CSUM_TX) 3668 info->key.tun_flags &= ~TUNNEL_CSUM; 3669 if (flags & BPF_F_SEQ_NUMBER) 3670 info->key.tun_flags |= TUNNEL_SEQ; 3671 3672 info->key.tun_id = cpu_to_be64(from->tunnel_id); 3673 info->key.tos = from->tunnel_tos; 3674 info->key.ttl = from->tunnel_ttl; 3675 3676 if (flags & BPF_F_TUNINFO_IPV6) { 3677 info->mode |= IP_TUNNEL_INFO_IPV6; 3678 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6, 3679 sizeof(from->remote_ipv6)); 3680 info->key.label = cpu_to_be32(from->tunnel_label) & 3681 IPV6_FLOWLABEL_MASK; 3682 } else { 3683 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4); 3684 } 3685 3686 return 0; 3687 } 3688 3689 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = { 3690 .func = bpf_skb_set_tunnel_key, 3691 .gpl_only = false, 3692 .ret_type = RET_INTEGER, 3693 .arg1_type = ARG_PTR_TO_CTX, 3694 .arg2_type = ARG_PTR_TO_MEM, 3695 .arg3_type = ARG_CONST_SIZE, 3696 .arg4_type = ARG_ANYTHING, 3697 }; 3698 3699 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb, 3700 const u8 *, from, u32, size) 3701 { 3702 struct ip_tunnel_info *info = skb_tunnel_info(skb); 3703 const struct metadata_dst *md = this_cpu_ptr(md_dst); 3704 3705 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1)))) 3706 return -EINVAL; 3707 if (unlikely(size > IP_TUNNEL_OPTS_MAX)) 3708 return -ENOMEM; 3709 3710 ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT); 3711 3712 return 0; 3713 } 3714 3715 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = { 3716 .func = bpf_skb_set_tunnel_opt, 3717 .gpl_only = false, 3718 .ret_type = RET_INTEGER, 3719 .arg1_type = ARG_PTR_TO_CTX, 3720 .arg2_type = ARG_PTR_TO_MEM, 3721 .arg3_type = ARG_CONST_SIZE, 3722 }; 3723 3724 static const struct bpf_func_proto * 3725 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which) 3726 { 3727 if (!md_dst) { 3728 struct metadata_dst __percpu *tmp; 3729 3730 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX, 3731 METADATA_IP_TUNNEL, 3732 GFP_KERNEL); 3733 if (!tmp) 3734 return NULL; 3735 if (cmpxchg(&md_dst, NULL, tmp)) 3736 metadata_dst_free_percpu(tmp); 3737 } 3738 3739 switch (which) { 3740 case BPF_FUNC_skb_set_tunnel_key: 3741 return &bpf_skb_set_tunnel_key_proto; 3742 case BPF_FUNC_skb_set_tunnel_opt: 3743 return &bpf_skb_set_tunnel_opt_proto; 3744 default: 3745 return NULL; 3746 } 3747 } 3748 3749 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map, 3750 u32, idx) 3751 { 3752 struct bpf_array *array = container_of(map, struct bpf_array, map); 3753 struct cgroup *cgrp; 3754 struct sock *sk; 3755 3756 sk = skb_to_full_sk(skb); 3757 if (!sk || !sk_fullsock(sk)) 3758 return -ENOENT; 3759 if (unlikely(idx >= array->map.max_entries)) 3760 return -E2BIG; 3761 3762 cgrp = READ_ONCE(array->ptrs[idx]); 3763 if (unlikely(!cgrp)) 3764 return -EAGAIN; 3765 3766 return sk_under_cgroup_hierarchy(sk, cgrp); 3767 } 3768 3769 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = { 3770 .func = bpf_skb_under_cgroup, 3771 .gpl_only = false, 3772 .ret_type = RET_INTEGER, 3773 .arg1_type = ARG_PTR_TO_CTX, 3774 .arg2_type = ARG_CONST_MAP_PTR, 3775 .arg3_type = ARG_ANYTHING, 3776 }; 3777 3778 #ifdef CONFIG_SOCK_CGROUP_DATA 3779 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb) 3780 { 3781 struct sock *sk = skb_to_full_sk(skb); 3782 struct cgroup *cgrp; 3783 3784 if (!sk || !sk_fullsock(sk)) 3785 return 0; 3786 3787 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data); 3788 return cgrp->kn->id.id; 3789 } 3790 3791 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = { 3792 .func = bpf_skb_cgroup_id, 3793 .gpl_only = false, 3794 .ret_type = RET_INTEGER, 3795 .arg1_type = ARG_PTR_TO_CTX, 3796 }; 3797 3798 BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int, 3799 ancestor_level) 3800 { 3801 struct sock *sk = skb_to_full_sk(skb); 3802 struct cgroup *ancestor; 3803 struct cgroup *cgrp; 3804 3805 if (!sk || !sk_fullsock(sk)) 3806 return 0; 3807 3808 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data); 3809 ancestor = cgroup_ancestor(cgrp, ancestor_level); 3810 if (!ancestor) 3811 return 0; 3812 3813 return ancestor->kn->id.id; 3814 } 3815 3816 static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = { 3817 .func = bpf_skb_ancestor_cgroup_id, 3818 .gpl_only = false, 3819 .ret_type = RET_INTEGER, 3820 .arg1_type = ARG_PTR_TO_CTX, 3821 .arg2_type = ARG_ANYTHING, 3822 }; 3823 #endif 3824 3825 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff, 3826 unsigned long off, unsigned long len) 3827 { 3828 memcpy(dst_buff, src_buff + off, len); 3829 return 0; 3830 } 3831 3832 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map, 3833 u64, flags, void *, meta, u64, meta_size) 3834 { 3835 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32; 3836 3837 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) 3838 return -EINVAL; 3839 if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data))) 3840 return -EFAULT; 3841 3842 return bpf_event_output(map, flags, meta, meta_size, xdp->data, 3843 xdp_size, bpf_xdp_copy); 3844 } 3845 3846 static const struct bpf_func_proto bpf_xdp_event_output_proto = { 3847 .func = bpf_xdp_event_output, 3848 .gpl_only = true, 3849 .ret_type = RET_INTEGER, 3850 .arg1_type = ARG_PTR_TO_CTX, 3851 .arg2_type = ARG_CONST_MAP_PTR, 3852 .arg3_type = ARG_ANYTHING, 3853 .arg4_type = ARG_PTR_TO_MEM, 3854 .arg5_type = ARG_CONST_SIZE_OR_ZERO, 3855 }; 3856 3857 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb) 3858 { 3859 return skb->sk ? sock_gen_cookie(skb->sk) : 0; 3860 } 3861 3862 static const struct bpf_func_proto bpf_get_socket_cookie_proto = { 3863 .func = bpf_get_socket_cookie, 3864 .gpl_only = false, 3865 .ret_type = RET_INTEGER, 3866 .arg1_type = ARG_PTR_TO_CTX, 3867 }; 3868 3869 BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx) 3870 { 3871 return sock_gen_cookie(ctx->sk); 3872 } 3873 3874 static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = { 3875 .func = bpf_get_socket_cookie_sock_addr, 3876 .gpl_only = false, 3877 .ret_type = RET_INTEGER, 3878 .arg1_type = ARG_PTR_TO_CTX, 3879 }; 3880 3881 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx) 3882 { 3883 return sock_gen_cookie(ctx->sk); 3884 } 3885 3886 static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = { 3887 .func = bpf_get_socket_cookie_sock_ops, 3888 .gpl_only = false, 3889 .ret_type = RET_INTEGER, 3890 .arg1_type = ARG_PTR_TO_CTX, 3891 }; 3892 3893 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb) 3894 { 3895 struct sock *sk = sk_to_full_sk(skb->sk); 3896 kuid_t kuid; 3897 3898 if (!sk || !sk_fullsock(sk)) 3899 return overflowuid; 3900 kuid = sock_net_uid(sock_net(sk), sk); 3901 return from_kuid_munged(sock_net(sk)->user_ns, kuid); 3902 } 3903 3904 static const struct bpf_func_proto bpf_get_socket_uid_proto = { 3905 .func = bpf_get_socket_uid, 3906 .gpl_only = false, 3907 .ret_type = RET_INTEGER, 3908 .arg1_type = ARG_PTR_TO_CTX, 3909 }; 3910 3911 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, 3912 int, level, int, optname, char *, optval, int, optlen) 3913 { 3914 struct sock *sk = bpf_sock->sk; 3915 int ret = 0; 3916 int val; 3917 3918 if (!sk_fullsock(sk)) 3919 return -EINVAL; 3920 3921 if (level == SOL_SOCKET) { 3922 if (optlen != sizeof(int)) 3923 return -EINVAL; 3924 val = *((int *)optval); 3925 3926 /* Only some socketops are supported */ 3927 switch (optname) { 3928 case SO_RCVBUF: 3929 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 3930 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF); 3931 break; 3932 case SO_SNDBUF: 3933 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 3934 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF); 3935 break; 3936 case SO_MAX_PACING_RATE: /* 32bit version */ 3937 sk->sk_max_pacing_rate = (val == ~0U) ? ~0UL : val; 3938 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 3939 sk->sk_max_pacing_rate); 3940 break; 3941 case SO_PRIORITY: 3942 sk->sk_priority = val; 3943 break; 3944 case SO_RCVLOWAT: 3945 if (val < 0) 3946 val = INT_MAX; 3947 sk->sk_rcvlowat = val ? : 1; 3948 break; 3949 case SO_MARK: 3950 sk->sk_mark = val; 3951 break; 3952 default: 3953 ret = -EINVAL; 3954 } 3955 #ifdef CONFIG_INET 3956 } else if (level == SOL_IP) { 3957 if (optlen != sizeof(int) || sk->sk_family != AF_INET) 3958 return -EINVAL; 3959 3960 val = *((int *)optval); 3961 /* Only some options are supported */ 3962 switch (optname) { 3963 case IP_TOS: 3964 if (val < -1 || val > 0xff) { 3965 ret = -EINVAL; 3966 } else { 3967 struct inet_sock *inet = inet_sk(sk); 3968 3969 if (val == -1) 3970 val = 0; 3971 inet->tos = val; 3972 } 3973 break; 3974 default: 3975 ret = -EINVAL; 3976 } 3977 #if IS_ENABLED(CONFIG_IPV6) 3978 } else if (level == SOL_IPV6) { 3979 if (optlen != sizeof(int) || sk->sk_family != AF_INET6) 3980 return -EINVAL; 3981 3982 val = *((int *)optval); 3983 /* Only some options are supported */ 3984 switch (optname) { 3985 case IPV6_TCLASS: 3986 if (val < -1 || val > 0xff) { 3987 ret = -EINVAL; 3988 } else { 3989 struct ipv6_pinfo *np = inet6_sk(sk); 3990 3991 if (val == -1) 3992 val = 0; 3993 np->tclass = val; 3994 } 3995 break; 3996 default: 3997 ret = -EINVAL; 3998 } 3999 #endif 4000 } else if (level == SOL_TCP && 4001 sk->sk_prot->setsockopt == tcp_setsockopt) { 4002 if (optname == TCP_CONGESTION) { 4003 char name[TCP_CA_NAME_MAX]; 4004 bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN; 4005 4006 strncpy(name, optval, min_t(long, optlen, 4007 TCP_CA_NAME_MAX-1)); 4008 name[TCP_CA_NAME_MAX-1] = 0; 4009 ret = tcp_set_congestion_control(sk, name, false, 4010 reinit); 4011 } else { 4012 struct tcp_sock *tp = tcp_sk(sk); 4013 4014 if (optlen != sizeof(int)) 4015 return -EINVAL; 4016 4017 val = *((int *)optval); 4018 /* Only some options are supported */ 4019 switch (optname) { 4020 case TCP_BPF_IW: 4021 if (val <= 0 || tp->data_segs_out > 0) 4022 ret = -EINVAL; 4023 else 4024 tp->snd_cwnd = val; 4025 break; 4026 case TCP_BPF_SNDCWND_CLAMP: 4027 if (val <= 0) { 4028 ret = -EINVAL; 4029 } else { 4030 tp->snd_cwnd_clamp = val; 4031 tp->snd_ssthresh = val; 4032 } 4033 break; 4034 case TCP_SAVE_SYN: 4035 if (val < 0 || val > 1) 4036 ret = -EINVAL; 4037 else 4038 tp->save_syn = val; 4039 break; 4040 default: 4041 ret = -EINVAL; 4042 } 4043 } 4044 #endif 4045 } else { 4046 ret = -EINVAL; 4047 } 4048 return ret; 4049 } 4050 4051 static const struct bpf_func_proto bpf_setsockopt_proto = { 4052 .func = bpf_setsockopt, 4053 .gpl_only = false, 4054 .ret_type = RET_INTEGER, 4055 .arg1_type = ARG_PTR_TO_CTX, 4056 .arg2_type = ARG_ANYTHING, 4057 .arg3_type = ARG_ANYTHING, 4058 .arg4_type = ARG_PTR_TO_MEM, 4059 .arg5_type = ARG_CONST_SIZE, 4060 }; 4061 4062 BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock, 4063 int, level, int, optname, char *, optval, int, optlen) 4064 { 4065 struct sock *sk = bpf_sock->sk; 4066 4067 if (!sk_fullsock(sk)) 4068 goto err_clear; 4069 #ifdef CONFIG_INET 4070 if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) { 4071 struct inet_connection_sock *icsk; 4072 struct tcp_sock *tp; 4073 4074 switch (optname) { 4075 case TCP_CONGESTION: 4076 icsk = inet_csk(sk); 4077 4078 if (!icsk->icsk_ca_ops || optlen <= 1) 4079 goto err_clear; 4080 strncpy(optval, icsk->icsk_ca_ops->name, optlen); 4081 optval[optlen - 1] = 0; 4082 break; 4083 case TCP_SAVED_SYN: 4084 tp = tcp_sk(sk); 4085 4086 if (optlen <= 0 || !tp->saved_syn || 4087 optlen > tp->saved_syn[0]) 4088 goto err_clear; 4089 memcpy(optval, tp->saved_syn + 1, optlen); 4090 break; 4091 default: 4092 goto err_clear; 4093 } 4094 } else if (level == SOL_IP) { 4095 struct inet_sock *inet = inet_sk(sk); 4096 4097 if (optlen != sizeof(int) || sk->sk_family != AF_INET) 4098 goto err_clear; 4099 4100 /* Only some options are supported */ 4101 switch (optname) { 4102 case IP_TOS: 4103 *((int *)optval) = (int)inet->tos; 4104 break; 4105 default: 4106 goto err_clear; 4107 } 4108 #if IS_ENABLED(CONFIG_IPV6) 4109 } else if (level == SOL_IPV6) { 4110 struct ipv6_pinfo *np = inet6_sk(sk); 4111 4112 if (optlen != sizeof(int) || sk->sk_family != AF_INET6) 4113 goto err_clear; 4114 4115 /* Only some options are supported */ 4116 switch (optname) { 4117 case IPV6_TCLASS: 4118 *((int *)optval) = (int)np->tclass; 4119 break; 4120 default: 4121 goto err_clear; 4122 } 4123 #endif 4124 } else { 4125 goto err_clear; 4126 } 4127 return 0; 4128 #endif 4129 err_clear: 4130 memset(optval, 0, optlen); 4131 return -EINVAL; 4132 } 4133 4134 static const struct bpf_func_proto bpf_getsockopt_proto = { 4135 .func = bpf_getsockopt, 4136 .gpl_only = false, 4137 .ret_type = RET_INTEGER, 4138 .arg1_type = ARG_PTR_TO_CTX, 4139 .arg2_type = ARG_ANYTHING, 4140 .arg3_type = ARG_ANYTHING, 4141 .arg4_type = ARG_PTR_TO_UNINIT_MEM, 4142 .arg5_type = ARG_CONST_SIZE, 4143 }; 4144 4145 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock, 4146 int, argval) 4147 { 4148 struct sock *sk = bpf_sock->sk; 4149 int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS; 4150 4151 if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk)) 4152 return -EINVAL; 4153 4154 if (val) 4155 tcp_sk(sk)->bpf_sock_ops_cb_flags = val; 4156 4157 return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS); 4158 } 4159 4160 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = { 4161 .func = bpf_sock_ops_cb_flags_set, 4162 .gpl_only = false, 4163 .ret_type = RET_INTEGER, 4164 .arg1_type = ARG_PTR_TO_CTX, 4165 .arg2_type = ARG_ANYTHING, 4166 }; 4167 4168 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly; 4169 EXPORT_SYMBOL_GPL(ipv6_bpf_stub); 4170 4171 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr, 4172 int, addr_len) 4173 { 4174 #ifdef CONFIG_INET 4175 struct sock *sk = ctx->sk; 4176 int err; 4177 4178 /* Binding to port can be expensive so it's prohibited in the helper. 4179 * Only binding to IP is supported. 4180 */ 4181 err = -EINVAL; 4182 if (addr->sa_family == AF_INET) { 4183 if (addr_len < sizeof(struct sockaddr_in)) 4184 return err; 4185 if (((struct sockaddr_in *)addr)->sin_port != htons(0)) 4186 return err; 4187 return __inet_bind(sk, addr, addr_len, true, false); 4188 #if IS_ENABLED(CONFIG_IPV6) 4189 } else if (addr->sa_family == AF_INET6) { 4190 if (addr_len < SIN6_LEN_RFC2133) 4191 return err; 4192 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) 4193 return err; 4194 /* ipv6_bpf_stub cannot be NULL, since it's called from 4195 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded 4196 */ 4197 return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, true, false); 4198 #endif /* CONFIG_IPV6 */ 4199 } 4200 #endif /* CONFIG_INET */ 4201 4202 return -EAFNOSUPPORT; 4203 } 4204 4205 static const struct bpf_func_proto bpf_bind_proto = { 4206 .func = bpf_bind, 4207 .gpl_only = false, 4208 .ret_type = RET_INTEGER, 4209 .arg1_type = ARG_PTR_TO_CTX, 4210 .arg2_type = ARG_PTR_TO_MEM, 4211 .arg3_type = ARG_CONST_SIZE, 4212 }; 4213 4214 #ifdef CONFIG_XFRM 4215 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index, 4216 struct bpf_xfrm_state *, to, u32, size, u64, flags) 4217 { 4218 const struct sec_path *sp = skb_sec_path(skb); 4219 const struct xfrm_state *x; 4220 4221 if (!sp || unlikely(index >= sp->len || flags)) 4222 goto err_clear; 4223 4224 x = sp->xvec[index]; 4225 4226 if (unlikely(size != sizeof(struct bpf_xfrm_state))) 4227 goto err_clear; 4228 4229 to->reqid = x->props.reqid; 4230 to->spi = x->id.spi; 4231 to->family = x->props.family; 4232 to->ext = 0; 4233 4234 if (to->family == AF_INET6) { 4235 memcpy(to->remote_ipv6, x->props.saddr.a6, 4236 sizeof(to->remote_ipv6)); 4237 } else { 4238 to->remote_ipv4 = x->props.saddr.a4; 4239 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3); 4240 } 4241 4242 return 0; 4243 err_clear: 4244 memset(to, 0, size); 4245 return -EINVAL; 4246 } 4247 4248 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = { 4249 .func = bpf_skb_get_xfrm_state, 4250 .gpl_only = false, 4251 .ret_type = RET_INTEGER, 4252 .arg1_type = ARG_PTR_TO_CTX, 4253 .arg2_type = ARG_ANYTHING, 4254 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 4255 .arg4_type = ARG_CONST_SIZE, 4256 .arg5_type = ARG_ANYTHING, 4257 }; 4258 #endif 4259 4260 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6) 4261 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, 4262 const struct neighbour *neigh, 4263 const struct net_device *dev) 4264 { 4265 memcpy(params->dmac, neigh->ha, ETH_ALEN); 4266 memcpy(params->smac, dev->dev_addr, ETH_ALEN); 4267 params->h_vlan_TCI = 0; 4268 params->h_vlan_proto = 0; 4269 params->ifindex = dev->ifindex; 4270 4271 return 0; 4272 } 4273 #endif 4274 4275 #if IS_ENABLED(CONFIG_INET) 4276 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, 4277 u32 flags, bool check_mtu) 4278 { 4279 struct in_device *in_dev; 4280 struct neighbour *neigh; 4281 struct net_device *dev; 4282 struct fib_result res; 4283 struct fib_nh *nh; 4284 struct flowi4 fl4; 4285 int err; 4286 u32 mtu; 4287 4288 dev = dev_get_by_index_rcu(net, params->ifindex); 4289 if (unlikely(!dev)) 4290 return -ENODEV; 4291 4292 /* verify forwarding is enabled on this interface */ 4293 in_dev = __in_dev_get_rcu(dev); 4294 if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev))) 4295 return BPF_FIB_LKUP_RET_FWD_DISABLED; 4296 4297 if (flags & BPF_FIB_LOOKUP_OUTPUT) { 4298 fl4.flowi4_iif = 1; 4299 fl4.flowi4_oif = params->ifindex; 4300 } else { 4301 fl4.flowi4_iif = params->ifindex; 4302 fl4.flowi4_oif = 0; 4303 } 4304 fl4.flowi4_tos = params->tos & IPTOS_RT_MASK; 4305 fl4.flowi4_scope = RT_SCOPE_UNIVERSE; 4306 fl4.flowi4_flags = 0; 4307 4308 fl4.flowi4_proto = params->l4_protocol; 4309 fl4.daddr = params->ipv4_dst; 4310 fl4.saddr = params->ipv4_src; 4311 fl4.fl4_sport = params->sport; 4312 fl4.fl4_dport = params->dport; 4313 4314 if (flags & BPF_FIB_LOOKUP_DIRECT) { 4315 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN; 4316 struct fib_table *tb; 4317 4318 tb = fib_get_table(net, tbid); 4319 if (unlikely(!tb)) 4320 return BPF_FIB_LKUP_RET_NOT_FWDED; 4321 4322 err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); 4323 } else { 4324 fl4.flowi4_mark = 0; 4325 fl4.flowi4_secid = 0; 4326 fl4.flowi4_tun_key.tun_id = 0; 4327 fl4.flowi4_uid = sock_net_uid(net, NULL); 4328 4329 err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF); 4330 } 4331 4332 if (err) { 4333 /* map fib lookup errors to RTN_ type */ 4334 if (err == -EINVAL) 4335 return BPF_FIB_LKUP_RET_BLACKHOLE; 4336 if (err == -EHOSTUNREACH) 4337 return BPF_FIB_LKUP_RET_UNREACHABLE; 4338 if (err == -EACCES) 4339 return BPF_FIB_LKUP_RET_PROHIBIT; 4340 4341 return BPF_FIB_LKUP_RET_NOT_FWDED; 4342 } 4343 4344 if (res.type != RTN_UNICAST) 4345 return BPF_FIB_LKUP_RET_NOT_FWDED; 4346 4347 if (res.fi->fib_nhs > 1) 4348 fib_select_path(net, &res, &fl4, NULL); 4349 4350 if (check_mtu) { 4351 mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst); 4352 if (params->tot_len > mtu) 4353 return BPF_FIB_LKUP_RET_FRAG_NEEDED; 4354 } 4355 4356 nh = &res.fi->fib_nh[res.nh_sel]; 4357 4358 /* do not handle lwt encaps right now */ 4359 if (nh->nh_lwtstate) 4360 return BPF_FIB_LKUP_RET_UNSUPP_LWT; 4361 4362 dev = nh->nh_dev; 4363 if (nh->nh_gw) 4364 params->ipv4_dst = nh->nh_gw; 4365 4366 params->rt_metric = res.fi->fib_priority; 4367 4368 /* xdp and cls_bpf programs are run in RCU-bh so 4369 * rcu_read_lock_bh is not needed here 4370 */ 4371 neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)params->ipv4_dst); 4372 if (!neigh) 4373 return BPF_FIB_LKUP_RET_NO_NEIGH; 4374 4375 return bpf_fib_set_fwd_params(params, neigh, dev); 4376 } 4377 #endif 4378 4379 #if IS_ENABLED(CONFIG_IPV6) 4380 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, 4381 u32 flags, bool check_mtu) 4382 { 4383 struct in6_addr *src = (struct in6_addr *) params->ipv6_src; 4384 struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst; 4385 struct neighbour *neigh; 4386 struct net_device *dev; 4387 struct inet6_dev *idev; 4388 struct fib6_info *f6i; 4389 struct flowi6 fl6; 4390 int strict = 0; 4391 int oif; 4392 u32 mtu; 4393 4394 /* link local addresses are never forwarded */ 4395 if (rt6_need_strict(dst) || rt6_need_strict(src)) 4396 return BPF_FIB_LKUP_RET_NOT_FWDED; 4397 4398 dev = dev_get_by_index_rcu(net, params->ifindex); 4399 if (unlikely(!dev)) 4400 return -ENODEV; 4401 4402 idev = __in6_dev_get_safely(dev); 4403 if (unlikely(!idev || !net->ipv6.devconf_all->forwarding)) 4404 return BPF_FIB_LKUP_RET_FWD_DISABLED; 4405 4406 if (flags & BPF_FIB_LOOKUP_OUTPUT) { 4407 fl6.flowi6_iif = 1; 4408 oif = fl6.flowi6_oif = params->ifindex; 4409 } else { 4410 oif = fl6.flowi6_iif = params->ifindex; 4411 fl6.flowi6_oif = 0; 4412 strict = RT6_LOOKUP_F_HAS_SADDR; 4413 } 4414 fl6.flowlabel = params->flowinfo; 4415 fl6.flowi6_scope = 0; 4416 fl6.flowi6_flags = 0; 4417 fl6.mp_hash = 0; 4418 4419 fl6.flowi6_proto = params->l4_protocol; 4420 fl6.daddr = *dst; 4421 fl6.saddr = *src; 4422 fl6.fl6_sport = params->sport; 4423 fl6.fl6_dport = params->dport; 4424 4425 if (flags & BPF_FIB_LOOKUP_DIRECT) { 4426 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN; 4427 struct fib6_table *tb; 4428 4429 tb = ipv6_stub->fib6_get_table(net, tbid); 4430 if (unlikely(!tb)) 4431 return BPF_FIB_LKUP_RET_NOT_FWDED; 4432 4433 f6i = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, strict); 4434 } else { 4435 fl6.flowi6_mark = 0; 4436 fl6.flowi6_secid = 0; 4437 fl6.flowi6_tun_key.tun_id = 0; 4438 fl6.flowi6_uid = sock_net_uid(net, NULL); 4439 4440 f6i = ipv6_stub->fib6_lookup(net, oif, &fl6, strict); 4441 } 4442 4443 if (unlikely(IS_ERR_OR_NULL(f6i) || f6i == net->ipv6.fib6_null_entry)) 4444 return BPF_FIB_LKUP_RET_NOT_FWDED; 4445 4446 if (unlikely(f6i->fib6_flags & RTF_REJECT)) { 4447 switch (f6i->fib6_type) { 4448 case RTN_BLACKHOLE: 4449 return BPF_FIB_LKUP_RET_BLACKHOLE; 4450 case RTN_UNREACHABLE: 4451 return BPF_FIB_LKUP_RET_UNREACHABLE; 4452 case RTN_PROHIBIT: 4453 return BPF_FIB_LKUP_RET_PROHIBIT; 4454 default: 4455 return BPF_FIB_LKUP_RET_NOT_FWDED; 4456 } 4457 } 4458 4459 if (f6i->fib6_type != RTN_UNICAST) 4460 return BPF_FIB_LKUP_RET_NOT_FWDED; 4461 4462 if (f6i->fib6_nsiblings && fl6.flowi6_oif == 0) 4463 f6i = ipv6_stub->fib6_multipath_select(net, f6i, &fl6, 4464 fl6.flowi6_oif, NULL, 4465 strict); 4466 4467 if (check_mtu) { 4468 mtu = ipv6_stub->ip6_mtu_from_fib6(f6i, dst, src); 4469 if (params->tot_len > mtu) 4470 return BPF_FIB_LKUP_RET_FRAG_NEEDED; 4471 } 4472 4473 if (f6i->fib6_nh.nh_lwtstate) 4474 return BPF_FIB_LKUP_RET_UNSUPP_LWT; 4475 4476 if (f6i->fib6_flags & RTF_GATEWAY) 4477 *dst = f6i->fib6_nh.nh_gw; 4478 4479 dev = f6i->fib6_nh.nh_dev; 4480 params->rt_metric = f6i->fib6_metric; 4481 4482 /* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is 4483 * not needed here. Can not use __ipv6_neigh_lookup_noref here 4484 * because we need to get nd_tbl via the stub 4485 */ 4486 neigh = ___neigh_lookup_noref(ipv6_stub->nd_tbl, neigh_key_eq128, 4487 ndisc_hashfn, dst, dev); 4488 if (!neigh) 4489 return BPF_FIB_LKUP_RET_NO_NEIGH; 4490 4491 return bpf_fib_set_fwd_params(params, neigh, dev); 4492 } 4493 #endif 4494 4495 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx, 4496 struct bpf_fib_lookup *, params, int, plen, u32, flags) 4497 { 4498 if (plen < sizeof(*params)) 4499 return -EINVAL; 4500 4501 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT)) 4502 return -EINVAL; 4503 4504 switch (params->family) { 4505 #if IS_ENABLED(CONFIG_INET) 4506 case AF_INET: 4507 return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params, 4508 flags, true); 4509 #endif 4510 #if IS_ENABLED(CONFIG_IPV6) 4511 case AF_INET6: 4512 return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params, 4513 flags, true); 4514 #endif 4515 } 4516 return -EAFNOSUPPORT; 4517 } 4518 4519 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = { 4520 .func = bpf_xdp_fib_lookup, 4521 .gpl_only = true, 4522 .ret_type = RET_INTEGER, 4523 .arg1_type = ARG_PTR_TO_CTX, 4524 .arg2_type = ARG_PTR_TO_MEM, 4525 .arg3_type = ARG_CONST_SIZE, 4526 .arg4_type = ARG_ANYTHING, 4527 }; 4528 4529 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb, 4530 struct bpf_fib_lookup *, params, int, plen, u32, flags) 4531 { 4532 struct net *net = dev_net(skb->dev); 4533 int rc = -EAFNOSUPPORT; 4534 4535 if (plen < sizeof(*params)) 4536 return -EINVAL; 4537 4538 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT)) 4539 return -EINVAL; 4540 4541 switch (params->family) { 4542 #if IS_ENABLED(CONFIG_INET) 4543 case AF_INET: 4544 rc = bpf_ipv4_fib_lookup(net, params, flags, false); 4545 break; 4546 #endif 4547 #if IS_ENABLED(CONFIG_IPV6) 4548 case AF_INET6: 4549 rc = bpf_ipv6_fib_lookup(net, params, flags, false); 4550 break; 4551 #endif 4552 } 4553 4554 if (!rc) { 4555 struct net_device *dev; 4556 4557 dev = dev_get_by_index_rcu(net, params->ifindex); 4558 if (!is_skb_forwardable(dev, skb)) 4559 rc = BPF_FIB_LKUP_RET_FRAG_NEEDED; 4560 } 4561 4562 return rc; 4563 } 4564 4565 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = { 4566 .func = bpf_skb_fib_lookup, 4567 .gpl_only = true, 4568 .ret_type = RET_INTEGER, 4569 .arg1_type = ARG_PTR_TO_CTX, 4570 .arg2_type = ARG_PTR_TO_MEM, 4571 .arg3_type = ARG_CONST_SIZE, 4572 .arg4_type = ARG_ANYTHING, 4573 }; 4574 4575 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4576 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len) 4577 { 4578 int err; 4579 struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr; 4580 4581 if (!seg6_validate_srh(srh, len)) 4582 return -EINVAL; 4583 4584 switch (type) { 4585 case BPF_LWT_ENCAP_SEG6_INLINE: 4586 if (skb->protocol != htons(ETH_P_IPV6)) 4587 return -EBADMSG; 4588 4589 err = seg6_do_srh_inline(skb, srh); 4590 break; 4591 case BPF_LWT_ENCAP_SEG6: 4592 skb_reset_inner_headers(skb); 4593 skb->encapsulation = 1; 4594 err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6); 4595 break; 4596 default: 4597 return -EINVAL; 4598 } 4599 4600 bpf_compute_data_pointers(skb); 4601 if (err) 4602 return err; 4603 4604 ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 4605 skb_set_transport_header(skb, sizeof(struct ipv6hdr)); 4606 4607 return seg6_lookup_nexthop(skb, NULL, 0); 4608 } 4609 #endif /* CONFIG_IPV6_SEG6_BPF */ 4610 4611 BPF_CALL_4(bpf_lwt_push_encap, struct sk_buff *, skb, u32, type, void *, hdr, 4612 u32, len) 4613 { 4614 switch (type) { 4615 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4616 case BPF_LWT_ENCAP_SEG6: 4617 case BPF_LWT_ENCAP_SEG6_INLINE: 4618 return bpf_push_seg6_encap(skb, type, hdr, len); 4619 #endif 4620 default: 4621 return -EINVAL; 4622 } 4623 } 4624 4625 static const struct bpf_func_proto bpf_lwt_push_encap_proto = { 4626 .func = bpf_lwt_push_encap, 4627 .gpl_only = false, 4628 .ret_type = RET_INTEGER, 4629 .arg1_type = ARG_PTR_TO_CTX, 4630 .arg2_type = ARG_ANYTHING, 4631 .arg3_type = ARG_PTR_TO_MEM, 4632 .arg4_type = ARG_CONST_SIZE 4633 }; 4634 4635 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4636 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset, 4637 const void *, from, u32, len) 4638 { 4639 struct seg6_bpf_srh_state *srh_state = 4640 this_cpu_ptr(&seg6_bpf_srh_states); 4641 struct ipv6_sr_hdr *srh = srh_state->srh; 4642 void *srh_tlvs, *srh_end, *ptr; 4643 int srhoff = 0; 4644 4645 if (srh == NULL) 4646 return -EINVAL; 4647 4648 srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4)); 4649 srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen); 4650 4651 ptr = skb->data + offset; 4652 if (ptr >= srh_tlvs && ptr + len <= srh_end) 4653 srh_state->valid = false; 4654 else if (ptr < (void *)&srh->flags || 4655 ptr + len > (void *)&srh->segments) 4656 return -EFAULT; 4657 4658 if (unlikely(bpf_try_make_writable(skb, offset + len))) 4659 return -EFAULT; 4660 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4661 return -EINVAL; 4662 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4663 4664 memcpy(skb->data + offset, from, len); 4665 return 0; 4666 } 4667 4668 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = { 4669 .func = bpf_lwt_seg6_store_bytes, 4670 .gpl_only = false, 4671 .ret_type = RET_INTEGER, 4672 .arg1_type = ARG_PTR_TO_CTX, 4673 .arg2_type = ARG_ANYTHING, 4674 .arg3_type = ARG_PTR_TO_MEM, 4675 .arg4_type = ARG_CONST_SIZE 4676 }; 4677 4678 static void bpf_update_srh_state(struct sk_buff *skb) 4679 { 4680 struct seg6_bpf_srh_state *srh_state = 4681 this_cpu_ptr(&seg6_bpf_srh_states); 4682 int srhoff = 0; 4683 4684 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) { 4685 srh_state->srh = NULL; 4686 } else { 4687 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4688 srh_state->hdrlen = srh_state->srh->hdrlen << 3; 4689 srh_state->valid = true; 4690 } 4691 } 4692 4693 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb, 4694 u32, action, void *, param, u32, param_len) 4695 { 4696 struct seg6_bpf_srh_state *srh_state = 4697 this_cpu_ptr(&seg6_bpf_srh_states); 4698 int hdroff = 0; 4699 int err; 4700 4701 switch (action) { 4702 case SEG6_LOCAL_ACTION_END_X: 4703 if (!seg6_bpf_has_valid_srh(skb)) 4704 return -EBADMSG; 4705 if (param_len != sizeof(struct in6_addr)) 4706 return -EINVAL; 4707 return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0); 4708 case SEG6_LOCAL_ACTION_END_T: 4709 if (!seg6_bpf_has_valid_srh(skb)) 4710 return -EBADMSG; 4711 if (param_len != sizeof(int)) 4712 return -EINVAL; 4713 return seg6_lookup_nexthop(skb, NULL, *(int *)param); 4714 case SEG6_LOCAL_ACTION_END_DT6: 4715 if (!seg6_bpf_has_valid_srh(skb)) 4716 return -EBADMSG; 4717 if (param_len != sizeof(int)) 4718 return -EINVAL; 4719 4720 if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0) 4721 return -EBADMSG; 4722 if (!pskb_pull(skb, hdroff)) 4723 return -EBADMSG; 4724 4725 skb_postpull_rcsum(skb, skb_network_header(skb), hdroff); 4726 skb_reset_network_header(skb); 4727 skb_reset_transport_header(skb); 4728 skb->encapsulation = 0; 4729 4730 bpf_compute_data_pointers(skb); 4731 bpf_update_srh_state(skb); 4732 return seg6_lookup_nexthop(skb, NULL, *(int *)param); 4733 case SEG6_LOCAL_ACTION_END_B6: 4734 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb)) 4735 return -EBADMSG; 4736 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE, 4737 param, param_len); 4738 if (!err) 4739 bpf_update_srh_state(skb); 4740 4741 return err; 4742 case SEG6_LOCAL_ACTION_END_B6_ENCAP: 4743 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb)) 4744 return -EBADMSG; 4745 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6, 4746 param, param_len); 4747 if (!err) 4748 bpf_update_srh_state(skb); 4749 4750 return err; 4751 default: 4752 return -EINVAL; 4753 } 4754 } 4755 4756 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = { 4757 .func = bpf_lwt_seg6_action, 4758 .gpl_only = false, 4759 .ret_type = RET_INTEGER, 4760 .arg1_type = ARG_PTR_TO_CTX, 4761 .arg2_type = ARG_ANYTHING, 4762 .arg3_type = ARG_PTR_TO_MEM, 4763 .arg4_type = ARG_CONST_SIZE 4764 }; 4765 4766 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset, 4767 s32, len) 4768 { 4769 struct seg6_bpf_srh_state *srh_state = 4770 this_cpu_ptr(&seg6_bpf_srh_states); 4771 struct ipv6_sr_hdr *srh = srh_state->srh; 4772 void *srh_end, *srh_tlvs, *ptr; 4773 struct ipv6hdr *hdr; 4774 int srhoff = 0; 4775 int ret; 4776 4777 if (unlikely(srh == NULL)) 4778 return -EINVAL; 4779 4780 srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) + 4781 ((srh->first_segment + 1) << 4)); 4782 srh_end = (void *)((unsigned char *)srh + sizeof(*srh) + 4783 srh_state->hdrlen); 4784 ptr = skb->data + offset; 4785 4786 if (unlikely(ptr < srh_tlvs || ptr > srh_end)) 4787 return -EFAULT; 4788 if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end)) 4789 return -EFAULT; 4790 4791 if (len > 0) { 4792 ret = skb_cow_head(skb, len); 4793 if (unlikely(ret < 0)) 4794 return ret; 4795 4796 ret = bpf_skb_net_hdr_push(skb, offset, len); 4797 } else { 4798 ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len); 4799 } 4800 4801 bpf_compute_data_pointers(skb); 4802 if (unlikely(ret < 0)) 4803 return ret; 4804 4805 hdr = (struct ipv6hdr *)skb->data; 4806 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 4807 4808 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4809 return -EINVAL; 4810 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4811 srh_state->hdrlen += len; 4812 srh_state->valid = false; 4813 return 0; 4814 } 4815 4816 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = { 4817 .func = bpf_lwt_seg6_adjust_srh, 4818 .gpl_only = false, 4819 .ret_type = RET_INTEGER, 4820 .arg1_type = ARG_PTR_TO_CTX, 4821 .arg2_type = ARG_ANYTHING, 4822 .arg3_type = ARG_ANYTHING, 4823 }; 4824 #endif /* CONFIG_IPV6_SEG6_BPF */ 4825 4826 #ifdef CONFIG_INET 4827 static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple, 4828 struct sk_buff *skb, u8 family, u8 proto) 4829 { 4830 bool refcounted = false; 4831 struct sock *sk = NULL; 4832 int dif = 0; 4833 4834 if (skb->dev) 4835 dif = skb->dev->ifindex; 4836 4837 if (family == AF_INET) { 4838 __be32 src4 = tuple->ipv4.saddr; 4839 __be32 dst4 = tuple->ipv4.daddr; 4840 int sdif = inet_sdif(skb); 4841 4842 if (proto == IPPROTO_TCP) 4843 sk = __inet_lookup(net, &tcp_hashinfo, skb, 0, 4844 src4, tuple->ipv4.sport, 4845 dst4, tuple->ipv4.dport, 4846 dif, sdif, &refcounted); 4847 else 4848 sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport, 4849 dst4, tuple->ipv4.dport, 4850 dif, sdif, &udp_table, skb); 4851 #if IS_ENABLED(CONFIG_IPV6) 4852 } else { 4853 struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr; 4854 struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr; 4855 u16 hnum = ntohs(tuple->ipv6.dport); 4856 int sdif = inet6_sdif(skb); 4857 4858 if (proto == IPPROTO_TCP) 4859 sk = __inet6_lookup(net, &tcp_hashinfo, skb, 0, 4860 src6, tuple->ipv6.sport, 4861 dst6, hnum, 4862 dif, sdif, &refcounted); 4863 else if (likely(ipv6_bpf_stub)) 4864 sk = ipv6_bpf_stub->udp6_lib_lookup(net, 4865 src6, tuple->ipv6.sport, 4866 dst6, hnum, 4867 dif, sdif, 4868 &udp_table, skb); 4869 #endif 4870 } 4871 4872 if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) { 4873 WARN_ONCE(1, "Found non-RCU, unreferenced socket!"); 4874 sk = NULL; 4875 } 4876 return sk; 4877 } 4878 4879 /* bpf_sk_lookup performs the core lookup for different types of sockets, 4880 * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE. 4881 * Returns the socket as an 'unsigned long' to simplify the casting in the 4882 * callers to satisfy BPF_CALL declarations. 4883 */ 4884 static unsigned long 4885 bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len, 4886 u8 proto, u64 netns_id, u64 flags) 4887 { 4888 struct net *caller_net; 4889 struct sock *sk = NULL; 4890 u8 family = AF_UNSPEC; 4891 struct net *net; 4892 4893 family = len == sizeof(tuple->ipv4) ? AF_INET : AF_INET6; 4894 if (unlikely(family == AF_UNSPEC || netns_id > U32_MAX || flags)) 4895 goto out; 4896 4897 if (skb->dev) 4898 caller_net = dev_net(skb->dev); 4899 else 4900 caller_net = sock_net(skb->sk); 4901 if (netns_id) { 4902 net = get_net_ns_by_id(caller_net, netns_id); 4903 if (unlikely(!net)) 4904 goto out; 4905 sk = sk_lookup(net, tuple, skb, family, proto); 4906 put_net(net); 4907 } else { 4908 net = caller_net; 4909 sk = sk_lookup(net, tuple, skb, family, proto); 4910 } 4911 4912 if (sk) 4913 sk = sk_to_full_sk(sk); 4914 out: 4915 return (unsigned long) sk; 4916 } 4917 4918 BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb, 4919 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags) 4920 { 4921 return bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP, netns_id, flags); 4922 } 4923 4924 static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = { 4925 .func = bpf_sk_lookup_tcp, 4926 .gpl_only = false, 4927 .pkt_access = true, 4928 .ret_type = RET_PTR_TO_SOCKET_OR_NULL, 4929 .arg1_type = ARG_PTR_TO_CTX, 4930 .arg2_type = ARG_PTR_TO_MEM, 4931 .arg3_type = ARG_CONST_SIZE, 4932 .arg4_type = ARG_ANYTHING, 4933 .arg5_type = ARG_ANYTHING, 4934 }; 4935 4936 BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb, 4937 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags) 4938 { 4939 return bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP, netns_id, flags); 4940 } 4941 4942 static const struct bpf_func_proto bpf_sk_lookup_udp_proto = { 4943 .func = bpf_sk_lookup_udp, 4944 .gpl_only = false, 4945 .pkt_access = true, 4946 .ret_type = RET_PTR_TO_SOCKET_OR_NULL, 4947 .arg1_type = ARG_PTR_TO_CTX, 4948 .arg2_type = ARG_PTR_TO_MEM, 4949 .arg3_type = ARG_CONST_SIZE, 4950 .arg4_type = ARG_ANYTHING, 4951 .arg5_type = ARG_ANYTHING, 4952 }; 4953 4954 BPF_CALL_1(bpf_sk_release, struct sock *, sk) 4955 { 4956 if (!sock_flag(sk, SOCK_RCU_FREE)) 4957 sock_gen_put(sk); 4958 return 0; 4959 } 4960 4961 static const struct bpf_func_proto bpf_sk_release_proto = { 4962 .func = bpf_sk_release, 4963 .gpl_only = false, 4964 .ret_type = RET_INTEGER, 4965 .arg1_type = ARG_PTR_TO_SOCKET, 4966 }; 4967 #endif /* CONFIG_INET */ 4968 4969 bool bpf_helper_changes_pkt_data(void *func) 4970 { 4971 if (func == bpf_skb_vlan_push || 4972 func == bpf_skb_vlan_pop || 4973 func == bpf_skb_store_bytes || 4974 func == bpf_skb_change_proto || 4975 func == bpf_skb_change_head || 4976 func == sk_skb_change_head || 4977 func == bpf_skb_change_tail || 4978 func == sk_skb_change_tail || 4979 func == bpf_skb_adjust_room || 4980 func == bpf_skb_pull_data || 4981 func == sk_skb_pull_data || 4982 func == bpf_clone_redirect || 4983 func == bpf_l3_csum_replace || 4984 func == bpf_l4_csum_replace || 4985 func == bpf_xdp_adjust_head || 4986 func == bpf_xdp_adjust_meta || 4987 func == bpf_msg_pull_data || 4988 func == bpf_msg_push_data || 4989 func == bpf_xdp_adjust_tail || 4990 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4991 func == bpf_lwt_seg6_store_bytes || 4992 func == bpf_lwt_seg6_adjust_srh || 4993 func == bpf_lwt_seg6_action || 4994 #endif 4995 func == bpf_lwt_push_encap) 4996 return true; 4997 4998 return false; 4999 } 5000 5001 static const struct bpf_func_proto * 5002 bpf_base_func_proto(enum bpf_func_id func_id) 5003 { 5004 switch (func_id) { 5005 case BPF_FUNC_map_lookup_elem: 5006 return &bpf_map_lookup_elem_proto; 5007 case BPF_FUNC_map_update_elem: 5008 return &bpf_map_update_elem_proto; 5009 case BPF_FUNC_map_delete_elem: 5010 return &bpf_map_delete_elem_proto; 5011 case BPF_FUNC_map_push_elem: 5012 return &bpf_map_push_elem_proto; 5013 case BPF_FUNC_map_pop_elem: 5014 return &bpf_map_pop_elem_proto; 5015 case BPF_FUNC_map_peek_elem: 5016 return &bpf_map_peek_elem_proto; 5017 case BPF_FUNC_get_prandom_u32: 5018 return &bpf_get_prandom_u32_proto; 5019 case BPF_FUNC_get_smp_processor_id: 5020 return &bpf_get_raw_smp_processor_id_proto; 5021 case BPF_FUNC_get_numa_node_id: 5022 return &bpf_get_numa_node_id_proto; 5023 case BPF_FUNC_tail_call: 5024 return &bpf_tail_call_proto; 5025 case BPF_FUNC_ktime_get_ns: 5026 return &bpf_ktime_get_ns_proto; 5027 case BPF_FUNC_trace_printk: 5028 if (capable(CAP_SYS_ADMIN)) 5029 return bpf_get_trace_printk_proto(); 5030 /* else: fall through */ 5031 default: 5032 return NULL; 5033 } 5034 } 5035 5036 static const struct bpf_func_proto * 5037 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5038 { 5039 switch (func_id) { 5040 /* inet and inet6 sockets are created in a process 5041 * context so there is always a valid uid/gid 5042 */ 5043 case BPF_FUNC_get_current_uid_gid: 5044 return &bpf_get_current_uid_gid_proto; 5045 case BPF_FUNC_get_local_storage: 5046 return &bpf_get_local_storage_proto; 5047 default: 5048 return bpf_base_func_proto(func_id); 5049 } 5050 } 5051 5052 static const struct bpf_func_proto * 5053 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5054 { 5055 switch (func_id) { 5056 /* inet and inet6 sockets are created in a process 5057 * context so there is always a valid uid/gid 5058 */ 5059 case BPF_FUNC_get_current_uid_gid: 5060 return &bpf_get_current_uid_gid_proto; 5061 case BPF_FUNC_bind: 5062 switch (prog->expected_attach_type) { 5063 case BPF_CGROUP_INET4_CONNECT: 5064 case BPF_CGROUP_INET6_CONNECT: 5065 return &bpf_bind_proto; 5066 default: 5067 return NULL; 5068 } 5069 case BPF_FUNC_get_socket_cookie: 5070 return &bpf_get_socket_cookie_sock_addr_proto; 5071 case BPF_FUNC_get_local_storage: 5072 return &bpf_get_local_storage_proto; 5073 default: 5074 return bpf_base_func_proto(func_id); 5075 } 5076 } 5077 5078 static const struct bpf_func_proto * 5079 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5080 { 5081 switch (func_id) { 5082 case BPF_FUNC_skb_load_bytes: 5083 return &bpf_skb_load_bytes_proto; 5084 case BPF_FUNC_skb_load_bytes_relative: 5085 return &bpf_skb_load_bytes_relative_proto; 5086 case BPF_FUNC_get_socket_cookie: 5087 return &bpf_get_socket_cookie_proto; 5088 case BPF_FUNC_get_socket_uid: 5089 return &bpf_get_socket_uid_proto; 5090 default: 5091 return bpf_base_func_proto(func_id); 5092 } 5093 } 5094 5095 static const struct bpf_func_proto * 5096 cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5097 { 5098 switch (func_id) { 5099 case BPF_FUNC_get_local_storage: 5100 return &bpf_get_local_storage_proto; 5101 default: 5102 return sk_filter_func_proto(func_id, prog); 5103 } 5104 } 5105 5106 static const struct bpf_func_proto * 5107 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5108 { 5109 switch (func_id) { 5110 case BPF_FUNC_skb_store_bytes: 5111 return &bpf_skb_store_bytes_proto; 5112 case BPF_FUNC_skb_load_bytes: 5113 return &bpf_skb_load_bytes_proto; 5114 case BPF_FUNC_skb_load_bytes_relative: 5115 return &bpf_skb_load_bytes_relative_proto; 5116 case BPF_FUNC_skb_pull_data: 5117 return &bpf_skb_pull_data_proto; 5118 case BPF_FUNC_csum_diff: 5119 return &bpf_csum_diff_proto; 5120 case BPF_FUNC_csum_update: 5121 return &bpf_csum_update_proto; 5122 case BPF_FUNC_l3_csum_replace: 5123 return &bpf_l3_csum_replace_proto; 5124 case BPF_FUNC_l4_csum_replace: 5125 return &bpf_l4_csum_replace_proto; 5126 case BPF_FUNC_clone_redirect: 5127 return &bpf_clone_redirect_proto; 5128 case BPF_FUNC_get_cgroup_classid: 5129 return &bpf_get_cgroup_classid_proto; 5130 case BPF_FUNC_skb_vlan_push: 5131 return &bpf_skb_vlan_push_proto; 5132 case BPF_FUNC_skb_vlan_pop: 5133 return &bpf_skb_vlan_pop_proto; 5134 case BPF_FUNC_skb_change_proto: 5135 return &bpf_skb_change_proto_proto; 5136 case BPF_FUNC_skb_change_type: 5137 return &bpf_skb_change_type_proto; 5138 case BPF_FUNC_skb_adjust_room: 5139 return &bpf_skb_adjust_room_proto; 5140 case BPF_FUNC_skb_change_tail: 5141 return &bpf_skb_change_tail_proto; 5142 case BPF_FUNC_skb_get_tunnel_key: 5143 return &bpf_skb_get_tunnel_key_proto; 5144 case BPF_FUNC_skb_set_tunnel_key: 5145 return bpf_get_skb_set_tunnel_proto(func_id); 5146 case BPF_FUNC_skb_get_tunnel_opt: 5147 return &bpf_skb_get_tunnel_opt_proto; 5148 case BPF_FUNC_skb_set_tunnel_opt: 5149 return bpf_get_skb_set_tunnel_proto(func_id); 5150 case BPF_FUNC_redirect: 5151 return &bpf_redirect_proto; 5152 case BPF_FUNC_get_route_realm: 5153 return &bpf_get_route_realm_proto; 5154 case BPF_FUNC_get_hash_recalc: 5155 return &bpf_get_hash_recalc_proto; 5156 case BPF_FUNC_set_hash_invalid: 5157 return &bpf_set_hash_invalid_proto; 5158 case BPF_FUNC_set_hash: 5159 return &bpf_set_hash_proto; 5160 case BPF_FUNC_perf_event_output: 5161 return &bpf_skb_event_output_proto; 5162 case BPF_FUNC_get_smp_processor_id: 5163 return &bpf_get_smp_processor_id_proto; 5164 case BPF_FUNC_skb_under_cgroup: 5165 return &bpf_skb_under_cgroup_proto; 5166 case BPF_FUNC_get_socket_cookie: 5167 return &bpf_get_socket_cookie_proto; 5168 case BPF_FUNC_get_socket_uid: 5169 return &bpf_get_socket_uid_proto; 5170 case BPF_FUNC_fib_lookup: 5171 return &bpf_skb_fib_lookup_proto; 5172 #ifdef CONFIG_XFRM 5173 case BPF_FUNC_skb_get_xfrm_state: 5174 return &bpf_skb_get_xfrm_state_proto; 5175 #endif 5176 #ifdef CONFIG_SOCK_CGROUP_DATA 5177 case BPF_FUNC_skb_cgroup_id: 5178 return &bpf_skb_cgroup_id_proto; 5179 case BPF_FUNC_skb_ancestor_cgroup_id: 5180 return &bpf_skb_ancestor_cgroup_id_proto; 5181 #endif 5182 #ifdef CONFIG_INET 5183 case BPF_FUNC_sk_lookup_tcp: 5184 return &bpf_sk_lookup_tcp_proto; 5185 case BPF_FUNC_sk_lookup_udp: 5186 return &bpf_sk_lookup_udp_proto; 5187 case BPF_FUNC_sk_release: 5188 return &bpf_sk_release_proto; 5189 #endif 5190 default: 5191 return bpf_base_func_proto(func_id); 5192 } 5193 } 5194 5195 static const struct bpf_func_proto * 5196 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5197 { 5198 switch (func_id) { 5199 case BPF_FUNC_perf_event_output: 5200 return &bpf_xdp_event_output_proto; 5201 case BPF_FUNC_get_smp_processor_id: 5202 return &bpf_get_smp_processor_id_proto; 5203 case BPF_FUNC_csum_diff: 5204 return &bpf_csum_diff_proto; 5205 case BPF_FUNC_xdp_adjust_head: 5206 return &bpf_xdp_adjust_head_proto; 5207 case BPF_FUNC_xdp_adjust_meta: 5208 return &bpf_xdp_adjust_meta_proto; 5209 case BPF_FUNC_redirect: 5210 return &bpf_xdp_redirect_proto; 5211 case BPF_FUNC_redirect_map: 5212 return &bpf_xdp_redirect_map_proto; 5213 case BPF_FUNC_xdp_adjust_tail: 5214 return &bpf_xdp_adjust_tail_proto; 5215 case BPF_FUNC_fib_lookup: 5216 return &bpf_xdp_fib_lookup_proto; 5217 default: 5218 return bpf_base_func_proto(func_id); 5219 } 5220 } 5221 5222 const struct bpf_func_proto bpf_sock_map_update_proto __weak; 5223 const struct bpf_func_proto bpf_sock_hash_update_proto __weak; 5224 5225 static const struct bpf_func_proto * 5226 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5227 { 5228 switch (func_id) { 5229 case BPF_FUNC_setsockopt: 5230 return &bpf_setsockopt_proto; 5231 case BPF_FUNC_getsockopt: 5232 return &bpf_getsockopt_proto; 5233 case BPF_FUNC_sock_ops_cb_flags_set: 5234 return &bpf_sock_ops_cb_flags_set_proto; 5235 case BPF_FUNC_sock_map_update: 5236 return &bpf_sock_map_update_proto; 5237 case BPF_FUNC_sock_hash_update: 5238 return &bpf_sock_hash_update_proto; 5239 case BPF_FUNC_get_socket_cookie: 5240 return &bpf_get_socket_cookie_sock_ops_proto; 5241 case BPF_FUNC_get_local_storage: 5242 return &bpf_get_local_storage_proto; 5243 default: 5244 return bpf_base_func_proto(func_id); 5245 } 5246 } 5247 5248 const struct bpf_func_proto bpf_msg_redirect_map_proto __weak; 5249 const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak; 5250 5251 static const struct bpf_func_proto * 5252 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5253 { 5254 switch (func_id) { 5255 case BPF_FUNC_msg_redirect_map: 5256 return &bpf_msg_redirect_map_proto; 5257 case BPF_FUNC_msg_redirect_hash: 5258 return &bpf_msg_redirect_hash_proto; 5259 case BPF_FUNC_msg_apply_bytes: 5260 return &bpf_msg_apply_bytes_proto; 5261 case BPF_FUNC_msg_cork_bytes: 5262 return &bpf_msg_cork_bytes_proto; 5263 case BPF_FUNC_msg_pull_data: 5264 return &bpf_msg_pull_data_proto; 5265 case BPF_FUNC_msg_push_data: 5266 return &bpf_msg_push_data_proto; 5267 default: 5268 return bpf_base_func_proto(func_id); 5269 } 5270 } 5271 5272 const struct bpf_func_proto bpf_sk_redirect_map_proto __weak; 5273 const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak; 5274 5275 static const struct bpf_func_proto * 5276 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5277 { 5278 switch (func_id) { 5279 case BPF_FUNC_skb_store_bytes: 5280 return &bpf_skb_store_bytes_proto; 5281 case BPF_FUNC_skb_load_bytes: 5282 return &bpf_skb_load_bytes_proto; 5283 case BPF_FUNC_skb_pull_data: 5284 return &sk_skb_pull_data_proto; 5285 case BPF_FUNC_skb_change_tail: 5286 return &sk_skb_change_tail_proto; 5287 case BPF_FUNC_skb_change_head: 5288 return &sk_skb_change_head_proto; 5289 case BPF_FUNC_get_socket_cookie: 5290 return &bpf_get_socket_cookie_proto; 5291 case BPF_FUNC_get_socket_uid: 5292 return &bpf_get_socket_uid_proto; 5293 case BPF_FUNC_sk_redirect_map: 5294 return &bpf_sk_redirect_map_proto; 5295 case BPF_FUNC_sk_redirect_hash: 5296 return &bpf_sk_redirect_hash_proto; 5297 #ifdef CONFIG_INET 5298 case BPF_FUNC_sk_lookup_tcp: 5299 return &bpf_sk_lookup_tcp_proto; 5300 case BPF_FUNC_sk_lookup_udp: 5301 return &bpf_sk_lookup_udp_proto; 5302 case BPF_FUNC_sk_release: 5303 return &bpf_sk_release_proto; 5304 #endif 5305 default: 5306 return bpf_base_func_proto(func_id); 5307 } 5308 } 5309 5310 static const struct bpf_func_proto * 5311 flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5312 { 5313 switch (func_id) { 5314 case BPF_FUNC_skb_load_bytes: 5315 return &bpf_skb_load_bytes_proto; 5316 default: 5317 return bpf_base_func_proto(func_id); 5318 } 5319 } 5320 5321 static const struct bpf_func_proto * 5322 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5323 { 5324 switch (func_id) { 5325 case BPF_FUNC_skb_load_bytes: 5326 return &bpf_skb_load_bytes_proto; 5327 case BPF_FUNC_skb_pull_data: 5328 return &bpf_skb_pull_data_proto; 5329 case BPF_FUNC_csum_diff: 5330 return &bpf_csum_diff_proto; 5331 case BPF_FUNC_get_cgroup_classid: 5332 return &bpf_get_cgroup_classid_proto; 5333 case BPF_FUNC_get_route_realm: 5334 return &bpf_get_route_realm_proto; 5335 case BPF_FUNC_get_hash_recalc: 5336 return &bpf_get_hash_recalc_proto; 5337 case BPF_FUNC_perf_event_output: 5338 return &bpf_skb_event_output_proto; 5339 case BPF_FUNC_get_smp_processor_id: 5340 return &bpf_get_smp_processor_id_proto; 5341 case BPF_FUNC_skb_under_cgroup: 5342 return &bpf_skb_under_cgroup_proto; 5343 default: 5344 return bpf_base_func_proto(func_id); 5345 } 5346 } 5347 5348 static const struct bpf_func_proto * 5349 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5350 { 5351 switch (func_id) { 5352 case BPF_FUNC_lwt_push_encap: 5353 return &bpf_lwt_push_encap_proto; 5354 default: 5355 return lwt_out_func_proto(func_id, prog); 5356 } 5357 } 5358 5359 static const struct bpf_func_proto * 5360 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5361 { 5362 switch (func_id) { 5363 case BPF_FUNC_skb_get_tunnel_key: 5364 return &bpf_skb_get_tunnel_key_proto; 5365 case BPF_FUNC_skb_set_tunnel_key: 5366 return bpf_get_skb_set_tunnel_proto(func_id); 5367 case BPF_FUNC_skb_get_tunnel_opt: 5368 return &bpf_skb_get_tunnel_opt_proto; 5369 case BPF_FUNC_skb_set_tunnel_opt: 5370 return bpf_get_skb_set_tunnel_proto(func_id); 5371 case BPF_FUNC_redirect: 5372 return &bpf_redirect_proto; 5373 case BPF_FUNC_clone_redirect: 5374 return &bpf_clone_redirect_proto; 5375 case BPF_FUNC_skb_change_tail: 5376 return &bpf_skb_change_tail_proto; 5377 case BPF_FUNC_skb_change_head: 5378 return &bpf_skb_change_head_proto; 5379 case BPF_FUNC_skb_store_bytes: 5380 return &bpf_skb_store_bytes_proto; 5381 case BPF_FUNC_csum_update: 5382 return &bpf_csum_update_proto; 5383 case BPF_FUNC_l3_csum_replace: 5384 return &bpf_l3_csum_replace_proto; 5385 case BPF_FUNC_l4_csum_replace: 5386 return &bpf_l4_csum_replace_proto; 5387 case BPF_FUNC_set_hash_invalid: 5388 return &bpf_set_hash_invalid_proto; 5389 default: 5390 return lwt_out_func_proto(func_id, prog); 5391 } 5392 } 5393 5394 static const struct bpf_func_proto * 5395 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5396 { 5397 switch (func_id) { 5398 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 5399 case BPF_FUNC_lwt_seg6_store_bytes: 5400 return &bpf_lwt_seg6_store_bytes_proto; 5401 case BPF_FUNC_lwt_seg6_action: 5402 return &bpf_lwt_seg6_action_proto; 5403 case BPF_FUNC_lwt_seg6_adjust_srh: 5404 return &bpf_lwt_seg6_adjust_srh_proto; 5405 #endif 5406 default: 5407 return lwt_out_func_proto(func_id, prog); 5408 } 5409 } 5410 5411 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type, 5412 const struct bpf_prog *prog, 5413 struct bpf_insn_access_aux *info) 5414 { 5415 const int size_default = sizeof(__u32); 5416 5417 if (off < 0 || off >= sizeof(struct __sk_buff)) 5418 return false; 5419 5420 /* The verifier guarantees that size > 0. */ 5421 if (off % size != 0) 5422 return false; 5423 5424 switch (off) { 5425 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5426 if (off + size > offsetofend(struct __sk_buff, cb[4])) 5427 return false; 5428 break; 5429 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]): 5430 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]): 5431 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4): 5432 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4): 5433 case bpf_ctx_range(struct __sk_buff, data): 5434 case bpf_ctx_range(struct __sk_buff, data_meta): 5435 case bpf_ctx_range(struct __sk_buff, data_end): 5436 if (size != size_default) 5437 return false; 5438 break; 5439 case bpf_ctx_range(struct __sk_buff, flow_keys): 5440 if (size != sizeof(struct bpf_flow_keys *)) 5441 return false; 5442 break; 5443 default: 5444 /* Only narrow read access allowed for now. */ 5445 if (type == BPF_WRITE) { 5446 if (size != size_default) 5447 return false; 5448 } else { 5449 bpf_ctx_record_field_size(info, size_default); 5450 if (!bpf_ctx_narrow_access_ok(off, size, size_default)) 5451 return false; 5452 } 5453 } 5454 5455 return true; 5456 } 5457 5458 static bool sk_filter_is_valid_access(int off, int size, 5459 enum bpf_access_type type, 5460 const struct bpf_prog *prog, 5461 struct bpf_insn_access_aux *info) 5462 { 5463 switch (off) { 5464 case bpf_ctx_range(struct __sk_buff, tc_classid): 5465 case bpf_ctx_range(struct __sk_buff, data): 5466 case bpf_ctx_range(struct __sk_buff, data_meta): 5467 case bpf_ctx_range(struct __sk_buff, data_end): 5468 case bpf_ctx_range(struct __sk_buff, flow_keys): 5469 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5470 return false; 5471 } 5472 5473 if (type == BPF_WRITE) { 5474 switch (off) { 5475 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5476 break; 5477 default: 5478 return false; 5479 } 5480 } 5481 5482 return bpf_skb_is_valid_access(off, size, type, prog, info); 5483 } 5484 5485 static bool cg_skb_is_valid_access(int off, int size, 5486 enum bpf_access_type type, 5487 const struct bpf_prog *prog, 5488 struct bpf_insn_access_aux *info) 5489 { 5490 switch (off) { 5491 case bpf_ctx_range(struct __sk_buff, tc_classid): 5492 case bpf_ctx_range(struct __sk_buff, data_meta): 5493 case bpf_ctx_range(struct __sk_buff, flow_keys): 5494 return false; 5495 case bpf_ctx_range(struct __sk_buff, data): 5496 case bpf_ctx_range(struct __sk_buff, data_end): 5497 if (!capable(CAP_SYS_ADMIN)) 5498 return false; 5499 break; 5500 } 5501 5502 if (type == BPF_WRITE) { 5503 switch (off) { 5504 case bpf_ctx_range(struct __sk_buff, mark): 5505 case bpf_ctx_range(struct __sk_buff, priority): 5506 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5507 break; 5508 default: 5509 return false; 5510 } 5511 } 5512 5513 switch (off) { 5514 case bpf_ctx_range(struct __sk_buff, data): 5515 info->reg_type = PTR_TO_PACKET; 5516 break; 5517 case bpf_ctx_range(struct __sk_buff, data_end): 5518 info->reg_type = PTR_TO_PACKET_END; 5519 break; 5520 } 5521 5522 return bpf_skb_is_valid_access(off, size, type, prog, info); 5523 } 5524 5525 static bool lwt_is_valid_access(int off, int size, 5526 enum bpf_access_type type, 5527 const struct bpf_prog *prog, 5528 struct bpf_insn_access_aux *info) 5529 { 5530 switch (off) { 5531 case bpf_ctx_range(struct __sk_buff, tc_classid): 5532 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5533 case bpf_ctx_range(struct __sk_buff, data_meta): 5534 case bpf_ctx_range(struct __sk_buff, flow_keys): 5535 return false; 5536 } 5537 5538 if (type == BPF_WRITE) { 5539 switch (off) { 5540 case bpf_ctx_range(struct __sk_buff, mark): 5541 case bpf_ctx_range(struct __sk_buff, priority): 5542 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5543 break; 5544 default: 5545 return false; 5546 } 5547 } 5548 5549 switch (off) { 5550 case bpf_ctx_range(struct __sk_buff, data): 5551 info->reg_type = PTR_TO_PACKET; 5552 break; 5553 case bpf_ctx_range(struct __sk_buff, data_end): 5554 info->reg_type = PTR_TO_PACKET_END; 5555 break; 5556 } 5557 5558 return bpf_skb_is_valid_access(off, size, type, prog, info); 5559 } 5560 5561 /* Attach type specific accesses */ 5562 static bool __sock_filter_check_attach_type(int off, 5563 enum bpf_access_type access_type, 5564 enum bpf_attach_type attach_type) 5565 { 5566 switch (off) { 5567 case offsetof(struct bpf_sock, bound_dev_if): 5568 case offsetof(struct bpf_sock, mark): 5569 case offsetof(struct bpf_sock, priority): 5570 switch (attach_type) { 5571 case BPF_CGROUP_INET_SOCK_CREATE: 5572 goto full_access; 5573 default: 5574 return false; 5575 } 5576 case bpf_ctx_range(struct bpf_sock, src_ip4): 5577 switch (attach_type) { 5578 case BPF_CGROUP_INET4_POST_BIND: 5579 goto read_only; 5580 default: 5581 return false; 5582 } 5583 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5584 switch (attach_type) { 5585 case BPF_CGROUP_INET6_POST_BIND: 5586 goto read_only; 5587 default: 5588 return false; 5589 } 5590 case bpf_ctx_range(struct bpf_sock, src_port): 5591 switch (attach_type) { 5592 case BPF_CGROUP_INET4_POST_BIND: 5593 case BPF_CGROUP_INET6_POST_BIND: 5594 goto read_only; 5595 default: 5596 return false; 5597 } 5598 } 5599 read_only: 5600 return access_type == BPF_READ; 5601 full_access: 5602 return true; 5603 } 5604 5605 static bool __sock_filter_check_size(int off, int size, 5606 struct bpf_insn_access_aux *info) 5607 { 5608 const int size_default = sizeof(__u32); 5609 5610 switch (off) { 5611 case bpf_ctx_range(struct bpf_sock, src_ip4): 5612 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5613 bpf_ctx_record_field_size(info, size_default); 5614 return bpf_ctx_narrow_access_ok(off, size, size_default); 5615 } 5616 5617 return size == size_default; 5618 } 5619 5620 bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type, 5621 struct bpf_insn_access_aux *info) 5622 { 5623 if (off < 0 || off >= sizeof(struct bpf_sock)) 5624 return false; 5625 if (off % size != 0) 5626 return false; 5627 if (!__sock_filter_check_size(off, size, info)) 5628 return false; 5629 return true; 5630 } 5631 5632 static bool sock_filter_is_valid_access(int off, int size, 5633 enum bpf_access_type type, 5634 const struct bpf_prog *prog, 5635 struct bpf_insn_access_aux *info) 5636 { 5637 if (!bpf_sock_is_valid_access(off, size, type, info)) 5638 return false; 5639 return __sock_filter_check_attach_type(off, type, 5640 prog->expected_attach_type); 5641 } 5642 5643 static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write, 5644 const struct bpf_prog *prog) 5645 { 5646 /* Neither direct read nor direct write requires any preliminary 5647 * action. 5648 */ 5649 return 0; 5650 } 5651 5652 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write, 5653 const struct bpf_prog *prog, int drop_verdict) 5654 { 5655 struct bpf_insn *insn = insn_buf; 5656 5657 if (!direct_write) 5658 return 0; 5659 5660 /* if (!skb->cloned) 5661 * goto start; 5662 * 5663 * (Fast-path, otherwise approximation that we might be 5664 * a clone, do the rest in helper.) 5665 */ 5666 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET()); 5667 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK); 5668 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7); 5669 5670 /* ret = bpf_skb_pull_data(skb, 0); */ 5671 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1); 5672 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2); 5673 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, 5674 BPF_FUNC_skb_pull_data); 5675 /* if (!ret) 5676 * goto restore; 5677 * return TC_ACT_SHOT; 5678 */ 5679 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2); 5680 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict); 5681 *insn++ = BPF_EXIT_INSN(); 5682 5683 /* restore: */ 5684 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6); 5685 /* start: */ 5686 *insn++ = prog->insnsi[0]; 5687 5688 return insn - insn_buf; 5689 } 5690 5691 static int bpf_gen_ld_abs(const struct bpf_insn *orig, 5692 struct bpf_insn *insn_buf) 5693 { 5694 bool indirect = BPF_MODE(orig->code) == BPF_IND; 5695 struct bpf_insn *insn = insn_buf; 5696 5697 /* We're guaranteed here that CTX is in R6. */ 5698 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX); 5699 if (!indirect) { 5700 *insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm); 5701 } else { 5702 *insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg); 5703 if (orig->imm) 5704 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm); 5705 } 5706 5707 switch (BPF_SIZE(orig->code)) { 5708 case BPF_B: 5709 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache); 5710 break; 5711 case BPF_H: 5712 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache); 5713 break; 5714 case BPF_W: 5715 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache); 5716 break; 5717 } 5718 5719 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2); 5720 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0); 5721 *insn++ = BPF_EXIT_INSN(); 5722 5723 return insn - insn_buf; 5724 } 5725 5726 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, 5727 const struct bpf_prog *prog) 5728 { 5729 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT); 5730 } 5731 5732 static bool tc_cls_act_is_valid_access(int off, int size, 5733 enum bpf_access_type type, 5734 const struct bpf_prog *prog, 5735 struct bpf_insn_access_aux *info) 5736 { 5737 if (type == BPF_WRITE) { 5738 switch (off) { 5739 case bpf_ctx_range(struct __sk_buff, mark): 5740 case bpf_ctx_range(struct __sk_buff, tc_index): 5741 case bpf_ctx_range(struct __sk_buff, priority): 5742 case bpf_ctx_range(struct __sk_buff, tc_classid): 5743 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5744 break; 5745 default: 5746 return false; 5747 } 5748 } 5749 5750 switch (off) { 5751 case bpf_ctx_range(struct __sk_buff, data): 5752 info->reg_type = PTR_TO_PACKET; 5753 break; 5754 case bpf_ctx_range(struct __sk_buff, data_meta): 5755 info->reg_type = PTR_TO_PACKET_META; 5756 break; 5757 case bpf_ctx_range(struct __sk_buff, data_end): 5758 info->reg_type = PTR_TO_PACKET_END; 5759 break; 5760 case bpf_ctx_range(struct __sk_buff, flow_keys): 5761 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5762 return false; 5763 } 5764 5765 return bpf_skb_is_valid_access(off, size, type, prog, info); 5766 } 5767 5768 static bool __is_valid_xdp_access(int off, int size) 5769 { 5770 if (off < 0 || off >= sizeof(struct xdp_md)) 5771 return false; 5772 if (off % size != 0) 5773 return false; 5774 if (size != sizeof(__u32)) 5775 return false; 5776 5777 return true; 5778 } 5779 5780 static bool xdp_is_valid_access(int off, int size, 5781 enum bpf_access_type type, 5782 const struct bpf_prog *prog, 5783 struct bpf_insn_access_aux *info) 5784 { 5785 if (type == BPF_WRITE) { 5786 if (bpf_prog_is_dev_bound(prog->aux)) { 5787 switch (off) { 5788 case offsetof(struct xdp_md, rx_queue_index): 5789 return __is_valid_xdp_access(off, size); 5790 } 5791 } 5792 return false; 5793 } 5794 5795 switch (off) { 5796 case offsetof(struct xdp_md, data): 5797 info->reg_type = PTR_TO_PACKET; 5798 break; 5799 case offsetof(struct xdp_md, data_meta): 5800 info->reg_type = PTR_TO_PACKET_META; 5801 break; 5802 case offsetof(struct xdp_md, data_end): 5803 info->reg_type = PTR_TO_PACKET_END; 5804 break; 5805 } 5806 5807 return __is_valid_xdp_access(off, size); 5808 } 5809 5810 void bpf_warn_invalid_xdp_action(u32 act) 5811 { 5812 const u32 act_max = XDP_REDIRECT; 5813 5814 WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n", 5815 act > act_max ? "Illegal" : "Driver unsupported", 5816 act); 5817 } 5818 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action); 5819 5820 static bool sock_addr_is_valid_access(int off, int size, 5821 enum bpf_access_type type, 5822 const struct bpf_prog *prog, 5823 struct bpf_insn_access_aux *info) 5824 { 5825 const int size_default = sizeof(__u32); 5826 5827 if (off < 0 || off >= sizeof(struct bpf_sock_addr)) 5828 return false; 5829 if (off % size != 0) 5830 return false; 5831 5832 /* Disallow access to IPv6 fields from IPv4 contex and vise 5833 * versa. 5834 */ 5835 switch (off) { 5836 case bpf_ctx_range(struct bpf_sock_addr, user_ip4): 5837 switch (prog->expected_attach_type) { 5838 case BPF_CGROUP_INET4_BIND: 5839 case BPF_CGROUP_INET4_CONNECT: 5840 case BPF_CGROUP_UDP4_SENDMSG: 5841 break; 5842 default: 5843 return false; 5844 } 5845 break; 5846 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 5847 switch (prog->expected_attach_type) { 5848 case BPF_CGROUP_INET6_BIND: 5849 case BPF_CGROUP_INET6_CONNECT: 5850 case BPF_CGROUP_UDP6_SENDMSG: 5851 break; 5852 default: 5853 return false; 5854 } 5855 break; 5856 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4): 5857 switch (prog->expected_attach_type) { 5858 case BPF_CGROUP_UDP4_SENDMSG: 5859 break; 5860 default: 5861 return false; 5862 } 5863 break; 5864 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 5865 msg_src_ip6[3]): 5866 switch (prog->expected_attach_type) { 5867 case BPF_CGROUP_UDP6_SENDMSG: 5868 break; 5869 default: 5870 return false; 5871 } 5872 break; 5873 } 5874 5875 switch (off) { 5876 case bpf_ctx_range(struct bpf_sock_addr, user_ip4): 5877 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 5878 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4): 5879 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 5880 msg_src_ip6[3]): 5881 /* Only narrow read access allowed for now. */ 5882 if (type == BPF_READ) { 5883 bpf_ctx_record_field_size(info, size_default); 5884 if (!bpf_ctx_narrow_access_ok(off, size, size_default)) 5885 return false; 5886 } else { 5887 if (size != size_default) 5888 return false; 5889 } 5890 break; 5891 case bpf_ctx_range(struct bpf_sock_addr, user_port): 5892 if (size != size_default) 5893 return false; 5894 break; 5895 default: 5896 if (type == BPF_READ) { 5897 if (size != size_default) 5898 return false; 5899 } else { 5900 return false; 5901 } 5902 } 5903 5904 return true; 5905 } 5906 5907 static bool sock_ops_is_valid_access(int off, int size, 5908 enum bpf_access_type type, 5909 const struct bpf_prog *prog, 5910 struct bpf_insn_access_aux *info) 5911 { 5912 const int size_default = sizeof(__u32); 5913 5914 if (off < 0 || off >= sizeof(struct bpf_sock_ops)) 5915 return false; 5916 5917 /* The verifier guarantees that size > 0. */ 5918 if (off % size != 0) 5919 return false; 5920 5921 if (type == BPF_WRITE) { 5922 switch (off) { 5923 case offsetof(struct bpf_sock_ops, reply): 5924 case offsetof(struct bpf_sock_ops, sk_txhash): 5925 if (size != size_default) 5926 return false; 5927 break; 5928 default: 5929 return false; 5930 } 5931 } else { 5932 switch (off) { 5933 case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received, 5934 bytes_acked): 5935 if (size != sizeof(__u64)) 5936 return false; 5937 break; 5938 default: 5939 if (size != size_default) 5940 return false; 5941 break; 5942 } 5943 } 5944 5945 return true; 5946 } 5947 5948 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write, 5949 const struct bpf_prog *prog) 5950 { 5951 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP); 5952 } 5953 5954 static bool sk_skb_is_valid_access(int off, int size, 5955 enum bpf_access_type type, 5956 const struct bpf_prog *prog, 5957 struct bpf_insn_access_aux *info) 5958 { 5959 switch (off) { 5960 case bpf_ctx_range(struct __sk_buff, tc_classid): 5961 case bpf_ctx_range(struct __sk_buff, data_meta): 5962 case bpf_ctx_range(struct __sk_buff, flow_keys): 5963 return false; 5964 } 5965 5966 if (type == BPF_WRITE) { 5967 switch (off) { 5968 case bpf_ctx_range(struct __sk_buff, tc_index): 5969 case bpf_ctx_range(struct __sk_buff, priority): 5970 break; 5971 default: 5972 return false; 5973 } 5974 } 5975 5976 switch (off) { 5977 case bpf_ctx_range(struct __sk_buff, mark): 5978 return false; 5979 case bpf_ctx_range(struct __sk_buff, data): 5980 info->reg_type = PTR_TO_PACKET; 5981 break; 5982 case bpf_ctx_range(struct __sk_buff, data_end): 5983 info->reg_type = PTR_TO_PACKET_END; 5984 break; 5985 } 5986 5987 return bpf_skb_is_valid_access(off, size, type, prog, info); 5988 } 5989 5990 static bool sk_msg_is_valid_access(int off, int size, 5991 enum bpf_access_type type, 5992 const struct bpf_prog *prog, 5993 struct bpf_insn_access_aux *info) 5994 { 5995 if (type == BPF_WRITE) 5996 return false; 5997 5998 switch (off) { 5999 case offsetof(struct sk_msg_md, data): 6000 info->reg_type = PTR_TO_PACKET; 6001 if (size != sizeof(__u64)) 6002 return false; 6003 break; 6004 case offsetof(struct sk_msg_md, data_end): 6005 info->reg_type = PTR_TO_PACKET_END; 6006 if (size != sizeof(__u64)) 6007 return false; 6008 break; 6009 default: 6010 if (size != sizeof(__u32)) 6011 return false; 6012 } 6013 6014 if (off < 0 || off >= sizeof(struct sk_msg_md)) 6015 return false; 6016 if (off % size != 0) 6017 return false; 6018 6019 return true; 6020 } 6021 6022 static bool flow_dissector_is_valid_access(int off, int size, 6023 enum bpf_access_type type, 6024 const struct bpf_prog *prog, 6025 struct bpf_insn_access_aux *info) 6026 { 6027 if (type == BPF_WRITE) { 6028 switch (off) { 6029 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 6030 break; 6031 default: 6032 return false; 6033 } 6034 } 6035 6036 switch (off) { 6037 case bpf_ctx_range(struct __sk_buff, data): 6038 info->reg_type = PTR_TO_PACKET; 6039 break; 6040 case bpf_ctx_range(struct __sk_buff, data_end): 6041 info->reg_type = PTR_TO_PACKET_END; 6042 break; 6043 case bpf_ctx_range(struct __sk_buff, flow_keys): 6044 info->reg_type = PTR_TO_FLOW_KEYS; 6045 break; 6046 case bpf_ctx_range(struct __sk_buff, tc_classid): 6047 case bpf_ctx_range(struct __sk_buff, data_meta): 6048 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 6049 return false; 6050 } 6051 6052 return bpf_skb_is_valid_access(off, size, type, prog, info); 6053 } 6054 6055 static u32 bpf_convert_ctx_access(enum bpf_access_type type, 6056 const struct bpf_insn *si, 6057 struct bpf_insn *insn_buf, 6058 struct bpf_prog *prog, u32 *target_size) 6059 { 6060 struct bpf_insn *insn = insn_buf; 6061 int off; 6062 6063 switch (si->off) { 6064 case offsetof(struct __sk_buff, len): 6065 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6066 bpf_target_off(struct sk_buff, len, 4, 6067 target_size)); 6068 break; 6069 6070 case offsetof(struct __sk_buff, protocol): 6071 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 6072 bpf_target_off(struct sk_buff, protocol, 2, 6073 target_size)); 6074 break; 6075 6076 case offsetof(struct __sk_buff, vlan_proto): 6077 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 6078 bpf_target_off(struct sk_buff, vlan_proto, 2, 6079 target_size)); 6080 break; 6081 6082 case offsetof(struct __sk_buff, priority): 6083 if (type == BPF_WRITE) 6084 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6085 bpf_target_off(struct sk_buff, priority, 4, 6086 target_size)); 6087 else 6088 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6089 bpf_target_off(struct sk_buff, priority, 4, 6090 target_size)); 6091 break; 6092 6093 case offsetof(struct __sk_buff, ingress_ifindex): 6094 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6095 bpf_target_off(struct sk_buff, skb_iif, 4, 6096 target_size)); 6097 break; 6098 6099 case offsetof(struct __sk_buff, ifindex): 6100 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 6101 si->dst_reg, si->src_reg, 6102 offsetof(struct sk_buff, dev)); 6103 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1); 6104 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6105 bpf_target_off(struct net_device, ifindex, 4, 6106 target_size)); 6107 break; 6108 6109 case offsetof(struct __sk_buff, hash): 6110 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6111 bpf_target_off(struct sk_buff, hash, 4, 6112 target_size)); 6113 break; 6114 6115 case offsetof(struct __sk_buff, mark): 6116 if (type == BPF_WRITE) 6117 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6118 bpf_target_off(struct sk_buff, mark, 4, 6119 target_size)); 6120 else 6121 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6122 bpf_target_off(struct sk_buff, mark, 4, 6123 target_size)); 6124 break; 6125 6126 case offsetof(struct __sk_buff, pkt_type): 6127 *target_size = 1; 6128 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg, 6129 PKT_TYPE_OFFSET()); 6130 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX); 6131 #ifdef __BIG_ENDIAN_BITFIELD 6132 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5); 6133 #endif 6134 break; 6135 6136 case offsetof(struct __sk_buff, queue_mapping): 6137 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 6138 bpf_target_off(struct sk_buff, queue_mapping, 2, 6139 target_size)); 6140 break; 6141 6142 case offsetof(struct __sk_buff, vlan_present): 6143 case offsetof(struct __sk_buff, vlan_tci): 6144 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); 6145 6146 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 6147 bpf_target_off(struct sk_buff, vlan_tci, 2, 6148 target_size)); 6149 if (si->off == offsetof(struct __sk_buff, vlan_tci)) { 6150 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 6151 ~VLAN_TAG_PRESENT); 6152 } else { 6153 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12); 6154 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1); 6155 } 6156 break; 6157 6158 case offsetof(struct __sk_buff, cb[0]) ... 6159 offsetofend(struct __sk_buff, cb[4]) - 1: 6160 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20); 6161 BUILD_BUG_ON((offsetof(struct sk_buff, cb) + 6162 offsetof(struct qdisc_skb_cb, data)) % 6163 sizeof(__u64)); 6164 6165 prog->cb_access = 1; 6166 off = si->off; 6167 off -= offsetof(struct __sk_buff, cb[0]); 6168 off += offsetof(struct sk_buff, cb); 6169 off += offsetof(struct qdisc_skb_cb, data); 6170 if (type == BPF_WRITE) 6171 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg, 6172 si->src_reg, off); 6173 else 6174 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg, 6175 si->src_reg, off); 6176 break; 6177 6178 case offsetof(struct __sk_buff, tc_classid): 6179 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2); 6180 6181 off = si->off; 6182 off -= offsetof(struct __sk_buff, tc_classid); 6183 off += offsetof(struct sk_buff, cb); 6184 off += offsetof(struct qdisc_skb_cb, tc_classid); 6185 *target_size = 2; 6186 if (type == BPF_WRITE) 6187 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, 6188 si->src_reg, off); 6189 else 6190 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, 6191 si->src_reg, off); 6192 break; 6193 6194 case offsetof(struct __sk_buff, data): 6195 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data), 6196 si->dst_reg, si->src_reg, 6197 offsetof(struct sk_buff, data)); 6198 break; 6199 6200 case offsetof(struct __sk_buff, data_meta): 6201 off = si->off; 6202 off -= offsetof(struct __sk_buff, data_meta); 6203 off += offsetof(struct sk_buff, cb); 6204 off += offsetof(struct bpf_skb_data_end, data_meta); 6205 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 6206 si->src_reg, off); 6207 break; 6208 6209 case offsetof(struct __sk_buff, data_end): 6210 off = si->off; 6211 off -= offsetof(struct __sk_buff, data_end); 6212 off += offsetof(struct sk_buff, cb); 6213 off += offsetof(struct bpf_skb_data_end, data_end); 6214 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 6215 si->src_reg, off); 6216 break; 6217 6218 case offsetof(struct __sk_buff, tc_index): 6219 #ifdef CONFIG_NET_SCHED 6220 if (type == BPF_WRITE) 6221 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg, 6222 bpf_target_off(struct sk_buff, tc_index, 2, 6223 target_size)); 6224 else 6225 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 6226 bpf_target_off(struct sk_buff, tc_index, 2, 6227 target_size)); 6228 #else 6229 *target_size = 2; 6230 if (type == BPF_WRITE) 6231 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg); 6232 else 6233 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 6234 #endif 6235 break; 6236 6237 case offsetof(struct __sk_buff, napi_id): 6238 #if defined(CONFIG_NET_RX_BUSY_POLL) 6239 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6240 bpf_target_off(struct sk_buff, napi_id, 4, 6241 target_size)); 6242 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1); 6243 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 6244 #else 6245 *target_size = 4; 6246 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 6247 #endif 6248 break; 6249 case offsetof(struct __sk_buff, family): 6250 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 6251 6252 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 6253 si->dst_reg, si->src_reg, 6254 offsetof(struct sk_buff, sk)); 6255 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6256 bpf_target_off(struct sock_common, 6257 skc_family, 6258 2, target_size)); 6259 break; 6260 case offsetof(struct __sk_buff, remote_ip4): 6261 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 6262 6263 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 6264 si->dst_reg, si->src_reg, 6265 offsetof(struct sk_buff, sk)); 6266 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6267 bpf_target_off(struct sock_common, 6268 skc_daddr, 6269 4, target_size)); 6270 break; 6271 case offsetof(struct __sk_buff, local_ip4): 6272 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6273 skc_rcv_saddr) != 4); 6274 6275 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 6276 si->dst_reg, si->src_reg, 6277 offsetof(struct sk_buff, sk)); 6278 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6279 bpf_target_off(struct sock_common, 6280 skc_rcv_saddr, 6281 4, target_size)); 6282 break; 6283 case offsetof(struct __sk_buff, remote_ip6[0]) ... 6284 offsetof(struct __sk_buff, remote_ip6[3]): 6285 #if IS_ENABLED(CONFIG_IPV6) 6286 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6287 skc_v6_daddr.s6_addr32[0]) != 4); 6288 6289 off = si->off; 6290 off -= offsetof(struct __sk_buff, remote_ip6[0]); 6291 6292 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 6293 si->dst_reg, si->src_reg, 6294 offsetof(struct sk_buff, sk)); 6295 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6296 offsetof(struct sock_common, 6297 skc_v6_daddr.s6_addr32[0]) + 6298 off); 6299 #else 6300 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6301 #endif 6302 break; 6303 case offsetof(struct __sk_buff, local_ip6[0]) ... 6304 offsetof(struct __sk_buff, local_ip6[3]): 6305 #if IS_ENABLED(CONFIG_IPV6) 6306 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6307 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 6308 6309 off = si->off; 6310 off -= offsetof(struct __sk_buff, local_ip6[0]); 6311 6312 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 6313 si->dst_reg, si->src_reg, 6314 offsetof(struct sk_buff, sk)); 6315 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6316 offsetof(struct sock_common, 6317 skc_v6_rcv_saddr.s6_addr32[0]) + 6318 off); 6319 #else 6320 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6321 #endif 6322 break; 6323 6324 case offsetof(struct __sk_buff, remote_port): 6325 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 6326 6327 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 6328 si->dst_reg, si->src_reg, 6329 offsetof(struct sk_buff, sk)); 6330 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6331 bpf_target_off(struct sock_common, 6332 skc_dport, 6333 2, target_size)); 6334 #ifndef __BIG_ENDIAN_BITFIELD 6335 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 6336 #endif 6337 break; 6338 6339 case offsetof(struct __sk_buff, local_port): 6340 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 6341 6342 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 6343 si->dst_reg, si->src_reg, 6344 offsetof(struct sk_buff, sk)); 6345 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6346 bpf_target_off(struct sock_common, 6347 skc_num, 2, target_size)); 6348 break; 6349 6350 case offsetof(struct __sk_buff, flow_keys): 6351 off = si->off; 6352 off -= offsetof(struct __sk_buff, flow_keys); 6353 off += offsetof(struct sk_buff, cb); 6354 off += offsetof(struct qdisc_skb_cb, flow_keys); 6355 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 6356 si->src_reg, off); 6357 break; 6358 } 6359 6360 return insn - insn_buf; 6361 } 6362 6363 u32 bpf_sock_convert_ctx_access(enum bpf_access_type type, 6364 const struct bpf_insn *si, 6365 struct bpf_insn *insn_buf, 6366 struct bpf_prog *prog, u32 *target_size) 6367 { 6368 struct bpf_insn *insn = insn_buf; 6369 int off; 6370 6371 switch (si->off) { 6372 case offsetof(struct bpf_sock, bound_dev_if): 6373 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4); 6374 6375 if (type == BPF_WRITE) 6376 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6377 offsetof(struct sock, sk_bound_dev_if)); 6378 else 6379 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6380 offsetof(struct sock, sk_bound_dev_if)); 6381 break; 6382 6383 case offsetof(struct bpf_sock, mark): 6384 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4); 6385 6386 if (type == BPF_WRITE) 6387 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6388 offsetof(struct sock, sk_mark)); 6389 else 6390 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6391 offsetof(struct sock, sk_mark)); 6392 break; 6393 6394 case offsetof(struct bpf_sock, priority): 6395 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4); 6396 6397 if (type == BPF_WRITE) 6398 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6399 offsetof(struct sock, sk_priority)); 6400 else 6401 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6402 offsetof(struct sock, sk_priority)); 6403 break; 6404 6405 case offsetof(struct bpf_sock, family): 6406 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2); 6407 6408 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 6409 offsetof(struct sock, sk_family)); 6410 break; 6411 6412 case offsetof(struct bpf_sock, type): 6413 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6414 offsetof(struct sock, __sk_flags_offset)); 6415 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK); 6416 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT); 6417 break; 6418 6419 case offsetof(struct bpf_sock, protocol): 6420 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6421 offsetof(struct sock, __sk_flags_offset)); 6422 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK); 6423 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT); 6424 break; 6425 6426 case offsetof(struct bpf_sock, src_ip4): 6427 *insn++ = BPF_LDX_MEM( 6428 BPF_SIZE(si->code), si->dst_reg, si->src_reg, 6429 bpf_target_off(struct sock_common, skc_rcv_saddr, 6430 FIELD_SIZEOF(struct sock_common, 6431 skc_rcv_saddr), 6432 target_size)); 6433 break; 6434 6435 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 6436 #if IS_ENABLED(CONFIG_IPV6) 6437 off = si->off; 6438 off -= offsetof(struct bpf_sock, src_ip6[0]); 6439 *insn++ = BPF_LDX_MEM( 6440 BPF_SIZE(si->code), si->dst_reg, si->src_reg, 6441 bpf_target_off( 6442 struct sock_common, 6443 skc_v6_rcv_saddr.s6_addr32[0], 6444 FIELD_SIZEOF(struct sock_common, 6445 skc_v6_rcv_saddr.s6_addr32[0]), 6446 target_size) + off); 6447 #else 6448 (void)off; 6449 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6450 #endif 6451 break; 6452 6453 case offsetof(struct bpf_sock, src_port): 6454 *insn++ = BPF_LDX_MEM( 6455 BPF_FIELD_SIZEOF(struct sock_common, skc_num), 6456 si->dst_reg, si->src_reg, 6457 bpf_target_off(struct sock_common, skc_num, 6458 FIELD_SIZEOF(struct sock_common, 6459 skc_num), 6460 target_size)); 6461 break; 6462 } 6463 6464 return insn - insn_buf; 6465 } 6466 6467 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type, 6468 const struct bpf_insn *si, 6469 struct bpf_insn *insn_buf, 6470 struct bpf_prog *prog, u32 *target_size) 6471 { 6472 struct bpf_insn *insn = insn_buf; 6473 6474 switch (si->off) { 6475 case offsetof(struct __sk_buff, ifindex): 6476 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 6477 si->dst_reg, si->src_reg, 6478 offsetof(struct sk_buff, dev)); 6479 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6480 bpf_target_off(struct net_device, ifindex, 4, 6481 target_size)); 6482 break; 6483 default: 6484 return bpf_convert_ctx_access(type, si, insn_buf, prog, 6485 target_size); 6486 } 6487 6488 return insn - insn_buf; 6489 } 6490 6491 static u32 xdp_convert_ctx_access(enum bpf_access_type type, 6492 const struct bpf_insn *si, 6493 struct bpf_insn *insn_buf, 6494 struct bpf_prog *prog, u32 *target_size) 6495 { 6496 struct bpf_insn *insn = insn_buf; 6497 6498 switch (si->off) { 6499 case offsetof(struct xdp_md, data): 6500 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data), 6501 si->dst_reg, si->src_reg, 6502 offsetof(struct xdp_buff, data)); 6503 break; 6504 case offsetof(struct xdp_md, data_meta): 6505 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta), 6506 si->dst_reg, si->src_reg, 6507 offsetof(struct xdp_buff, data_meta)); 6508 break; 6509 case offsetof(struct xdp_md, data_end): 6510 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end), 6511 si->dst_reg, si->src_reg, 6512 offsetof(struct xdp_buff, data_end)); 6513 break; 6514 case offsetof(struct xdp_md, ingress_ifindex): 6515 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq), 6516 si->dst_reg, si->src_reg, 6517 offsetof(struct xdp_buff, rxq)); 6518 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev), 6519 si->dst_reg, si->dst_reg, 6520 offsetof(struct xdp_rxq_info, dev)); 6521 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6522 offsetof(struct net_device, ifindex)); 6523 break; 6524 case offsetof(struct xdp_md, rx_queue_index): 6525 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq), 6526 si->dst_reg, si->src_reg, 6527 offsetof(struct xdp_buff, rxq)); 6528 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6529 offsetof(struct xdp_rxq_info, 6530 queue_index)); 6531 break; 6532 } 6533 6534 return insn - insn_buf; 6535 } 6536 6537 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of 6538 * context Structure, F is Field in context structure that contains a pointer 6539 * to Nested Structure of type NS that has the field NF. 6540 * 6541 * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make 6542 * sure that SIZE is not greater than actual size of S.F.NF. 6543 * 6544 * If offset OFF is provided, the load happens from that offset relative to 6545 * offset of NF. 6546 */ 6547 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF) \ 6548 do { \ 6549 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg, \ 6550 si->src_reg, offsetof(S, F)); \ 6551 *insn++ = BPF_LDX_MEM( \ 6552 SIZE, si->dst_reg, si->dst_reg, \ 6553 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \ 6554 target_size) \ 6555 + OFF); \ 6556 } while (0) 6557 6558 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF) \ 6559 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, \ 6560 BPF_FIELD_SIZEOF(NS, NF), 0) 6561 6562 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to 6563 * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation. 6564 * 6565 * It doesn't support SIZE argument though since narrow stores are not 6566 * supported for now. 6567 * 6568 * In addition it uses Temporary Field TF (member of struct S) as the 3rd 6569 * "register" since two registers available in convert_ctx_access are not 6570 * enough: we can't override neither SRC, since it contains value to store, nor 6571 * DST since it contains pointer to context that may be used by later 6572 * instructions. But we need a temporary place to save pointer to nested 6573 * structure whose field we want to store to. 6574 */ 6575 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, TF) \ 6576 do { \ 6577 int tmp_reg = BPF_REG_9; \ 6578 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \ 6579 --tmp_reg; \ 6580 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \ 6581 --tmp_reg; \ 6582 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg, \ 6583 offsetof(S, TF)); \ 6584 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg, \ 6585 si->dst_reg, offsetof(S, F)); \ 6586 *insn++ = BPF_STX_MEM( \ 6587 BPF_FIELD_SIZEOF(NS, NF), tmp_reg, si->src_reg, \ 6588 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \ 6589 target_size) \ 6590 + OFF); \ 6591 *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg, \ 6592 offsetof(S, TF)); \ 6593 } while (0) 6594 6595 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \ 6596 TF) \ 6597 do { \ 6598 if (type == BPF_WRITE) { \ 6599 SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, \ 6600 TF); \ 6601 } else { \ 6602 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( \ 6603 S, NS, F, NF, SIZE, OFF); \ 6604 } \ 6605 } while (0) 6606 6607 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF) \ 6608 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( \ 6609 S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF) 6610 6611 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type, 6612 const struct bpf_insn *si, 6613 struct bpf_insn *insn_buf, 6614 struct bpf_prog *prog, u32 *target_size) 6615 { 6616 struct bpf_insn *insn = insn_buf; 6617 int off; 6618 6619 switch (si->off) { 6620 case offsetof(struct bpf_sock_addr, user_family): 6621 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern, 6622 struct sockaddr, uaddr, sa_family); 6623 break; 6624 6625 case offsetof(struct bpf_sock_addr, user_ip4): 6626 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6627 struct bpf_sock_addr_kern, struct sockaddr_in, uaddr, 6628 sin_addr, BPF_SIZE(si->code), 0, tmp_reg); 6629 break; 6630 6631 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 6632 off = si->off; 6633 off -= offsetof(struct bpf_sock_addr, user_ip6[0]); 6634 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6635 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr, 6636 sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off, 6637 tmp_reg); 6638 break; 6639 6640 case offsetof(struct bpf_sock_addr, user_port): 6641 /* To get port we need to know sa_family first and then treat 6642 * sockaddr as either sockaddr_in or sockaddr_in6. 6643 * Though we can simplify since port field has same offset and 6644 * size in both structures. 6645 * Here we check this invariant and use just one of the 6646 * structures if it's true. 6647 */ 6648 BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) != 6649 offsetof(struct sockaddr_in6, sin6_port)); 6650 BUILD_BUG_ON(FIELD_SIZEOF(struct sockaddr_in, sin_port) != 6651 FIELD_SIZEOF(struct sockaddr_in6, sin6_port)); 6652 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(struct bpf_sock_addr_kern, 6653 struct sockaddr_in6, uaddr, 6654 sin6_port, tmp_reg); 6655 break; 6656 6657 case offsetof(struct bpf_sock_addr, family): 6658 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern, 6659 struct sock, sk, sk_family); 6660 break; 6661 6662 case offsetof(struct bpf_sock_addr, type): 6663 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( 6664 struct bpf_sock_addr_kern, struct sock, sk, 6665 __sk_flags_offset, BPF_W, 0); 6666 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK); 6667 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT); 6668 break; 6669 6670 case offsetof(struct bpf_sock_addr, protocol): 6671 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( 6672 struct bpf_sock_addr_kern, struct sock, sk, 6673 __sk_flags_offset, BPF_W, 0); 6674 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK); 6675 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 6676 SK_FL_PROTO_SHIFT); 6677 break; 6678 6679 case offsetof(struct bpf_sock_addr, msg_src_ip4): 6680 /* Treat t_ctx as struct in_addr for msg_src_ip4. */ 6681 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6682 struct bpf_sock_addr_kern, struct in_addr, t_ctx, 6683 s_addr, BPF_SIZE(si->code), 0, tmp_reg); 6684 break; 6685 6686 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 6687 msg_src_ip6[3]): 6688 off = si->off; 6689 off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]); 6690 /* Treat t_ctx as struct in6_addr for msg_src_ip6. */ 6691 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6692 struct bpf_sock_addr_kern, struct in6_addr, t_ctx, 6693 s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg); 6694 break; 6695 } 6696 6697 return insn - insn_buf; 6698 } 6699 6700 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, 6701 const struct bpf_insn *si, 6702 struct bpf_insn *insn_buf, 6703 struct bpf_prog *prog, 6704 u32 *target_size) 6705 { 6706 struct bpf_insn *insn = insn_buf; 6707 int off; 6708 6709 switch (si->off) { 6710 case offsetof(struct bpf_sock_ops, op) ... 6711 offsetof(struct bpf_sock_ops, replylong[3]): 6712 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) != 6713 FIELD_SIZEOF(struct bpf_sock_ops_kern, op)); 6714 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) != 6715 FIELD_SIZEOF(struct bpf_sock_ops_kern, reply)); 6716 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) != 6717 FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong)); 6718 off = si->off; 6719 off -= offsetof(struct bpf_sock_ops, op); 6720 off += offsetof(struct bpf_sock_ops_kern, op); 6721 if (type == BPF_WRITE) 6722 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6723 off); 6724 else 6725 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6726 off); 6727 break; 6728 6729 case offsetof(struct bpf_sock_ops, family): 6730 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 6731 6732 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6733 struct bpf_sock_ops_kern, sk), 6734 si->dst_reg, si->src_reg, 6735 offsetof(struct bpf_sock_ops_kern, sk)); 6736 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6737 offsetof(struct sock_common, skc_family)); 6738 break; 6739 6740 case offsetof(struct bpf_sock_ops, remote_ip4): 6741 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 6742 6743 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6744 struct bpf_sock_ops_kern, sk), 6745 si->dst_reg, si->src_reg, 6746 offsetof(struct bpf_sock_ops_kern, sk)); 6747 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6748 offsetof(struct sock_common, skc_daddr)); 6749 break; 6750 6751 case offsetof(struct bpf_sock_ops, local_ip4): 6752 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6753 skc_rcv_saddr) != 4); 6754 6755 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6756 struct bpf_sock_ops_kern, sk), 6757 si->dst_reg, si->src_reg, 6758 offsetof(struct bpf_sock_ops_kern, sk)); 6759 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6760 offsetof(struct sock_common, 6761 skc_rcv_saddr)); 6762 break; 6763 6764 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ... 6765 offsetof(struct bpf_sock_ops, remote_ip6[3]): 6766 #if IS_ENABLED(CONFIG_IPV6) 6767 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6768 skc_v6_daddr.s6_addr32[0]) != 4); 6769 6770 off = si->off; 6771 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]); 6772 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6773 struct bpf_sock_ops_kern, sk), 6774 si->dst_reg, si->src_reg, 6775 offsetof(struct bpf_sock_ops_kern, sk)); 6776 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6777 offsetof(struct sock_common, 6778 skc_v6_daddr.s6_addr32[0]) + 6779 off); 6780 #else 6781 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6782 #endif 6783 break; 6784 6785 case offsetof(struct bpf_sock_ops, local_ip6[0]) ... 6786 offsetof(struct bpf_sock_ops, local_ip6[3]): 6787 #if IS_ENABLED(CONFIG_IPV6) 6788 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6789 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 6790 6791 off = si->off; 6792 off -= offsetof(struct bpf_sock_ops, local_ip6[0]); 6793 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6794 struct bpf_sock_ops_kern, sk), 6795 si->dst_reg, si->src_reg, 6796 offsetof(struct bpf_sock_ops_kern, sk)); 6797 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6798 offsetof(struct sock_common, 6799 skc_v6_rcv_saddr.s6_addr32[0]) + 6800 off); 6801 #else 6802 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6803 #endif 6804 break; 6805 6806 case offsetof(struct bpf_sock_ops, remote_port): 6807 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 6808 6809 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6810 struct bpf_sock_ops_kern, sk), 6811 si->dst_reg, si->src_reg, 6812 offsetof(struct bpf_sock_ops_kern, sk)); 6813 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6814 offsetof(struct sock_common, skc_dport)); 6815 #ifndef __BIG_ENDIAN_BITFIELD 6816 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 6817 #endif 6818 break; 6819 6820 case offsetof(struct bpf_sock_ops, local_port): 6821 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 6822 6823 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6824 struct bpf_sock_ops_kern, sk), 6825 si->dst_reg, si->src_reg, 6826 offsetof(struct bpf_sock_ops_kern, sk)); 6827 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6828 offsetof(struct sock_common, skc_num)); 6829 break; 6830 6831 case offsetof(struct bpf_sock_ops, is_fullsock): 6832 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6833 struct bpf_sock_ops_kern, 6834 is_fullsock), 6835 si->dst_reg, si->src_reg, 6836 offsetof(struct bpf_sock_ops_kern, 6837 is_fullsock)); 6838 break; 6839 6840 case offsetof(struct bpf_sock_ops, state): 6841 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_state) != 1); 6842 6843 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6844 struct bpf_sock_ops_kern, sk), 6845 si->dst_reg, si->src_reg, 6846 offsetof(struct bpf_sock_ops_kern, sk)); 6847 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg, 6848 offsetof(struct sock_common, skc_state)); 6849 break; 6850 6851 case offsetof(struct bpf_sock_ops, rtt_min): 6852 BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, rtt_min) != 6853 sizeof(struct minmax)); 6854 BUILD_BUG_ON(sizeof(struct minmax) < 6855 sizeof(struct minmax_sample)); 6856 6857 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6858 struct bpf_sock_ops_kern, sk), 6859 si->dst_reg, si->src_reg, 6860 offsetof(struct bpf_sock_ops_kern, sk)); 6861 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6862 offsetof(struct tcp_sock, rtt_min) + 6863 FIELD_SIZEOF(struct minmax_sample, t)); 6864 break; 6865 6866 /* Helper macro for adding read access to tcp_sock or sock fields. */ 6867 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \ 6868 do { \ 6869 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \ 6870 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \ 6871 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6872 struct bpf_sock_ops_kern, \ 6873 is_fullsock), \ 6874 si->dst_reg, si->src_reg, \ 6875 offsetof(struct bpf_sock_ops_kern, \ 6876 is_fullsock)); \ 6877 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 2); \ 6878 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6879 struct bpf_sock_ops_kern, sk),\ 6880 si->dst_reg, si->src_reg, \ 6881 offsetof(struct bpf_sock_ops_kern, sk));\ 6882 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ, \ 6883 OBJ_FIELD), \ 6884 si->dst_reg, si->dst_reg, \ 6885 offsetof(OBJ, OBJ_FIELD)); \ 6886 } while (0) 6887 6888 /* Helper macro for adding write access to tcp_sock or sock fields. 6889 * The macro is called with two registers, dst_reg which contains a pointer 6890 * to ctx (context) and src_reg which contains the value that should be 6891 * stored. However, we need an additional register since we cannot overwrite 6892 * dst_reg because it may be used later in the program. 6893 * Instead we "borrow" one of the other register. We first save its value 6894 * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore 6895 * it at the end of the macro. 6896 */ 6897 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \ 6898 do { \ 6899 int reg = BPF_REG_9; \ 6900 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \ 6901 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \ 6902 if (si->dst_reg == reg || si->src_reg == reg) \ 6903 reg--; \ 6904 if (si->dst_reg == reg || si->src_reg == reg) \ 6905 reg--; \ 6906 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg, \ 6907 offsetof(struct bpf_sock_ops_kern, \ 6908 temp)); \ 6909 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6910 struct bpf_sock_ops_kern, \ 6911 is_fullsock), \ 6912 reg, si->dst_reg, \ 6913 offsetof(struct bpf_sock_ops_kern, \ 6914 is_fullsock)); \ 6915 *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2); \ 6916 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6917 struct bpf_sock_ops_kern, sk),\ 6918 reg, si->dst_reg, \ 6919 offsetof(struct bpf_sock_ops_kern, sk));\ 6920 *insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD), \ 6921 reg, si->src_reg, \ 6922 offsetof(OBJ, OBJ_FIELD)); \ 6923 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg, \ 6924 offsetof(struct bpf_sock_ops_kern, \ 6925 temp)); \ 6926 } while (0) 6927 6928 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE) \ 6929 do { \ 6930 if (TYPE == BPF_WRITE) \ 6931 SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \ 6932 else \ 6933 SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \ 6934 } while (0) 6935 6936 case offsetof(struct bpf_sock_ops, snd_cwnd): 6937 SOCK_OPS_GET_FIELD(snd_cwnd, snd_cwnd, struct tcp_sock); 6938 break; 6939 6940 case offsetof(struct bpf_sock_ops, srtt_us): 6941 SOCK_OPS_GET_FIELD(srtt_us, srtt_us, struct tcp_sock); 6942 break; 6943 6944 case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags): 6945 SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags, 6946 struct tcp_sock); 6947 break; 6948 6949 case offsetof(struct bpf_sock_ops, snd_ssthresh): 6950 SOCK_OPS_GET_FIELD(snd_ssthresh, snd_ssthresh, struct tcp_sock); 6951 break; 6952 6953 case offsetof(struct bpf_sock_ops, rcv_nxt): 6954 SOCK_OPS_GET_FIELD(rcv_nxt, rcv_nxt, struct tcp_sock); 6955 break; 6956 6957 case offsetof(struct bpf_sock_ops, snd_nxt): 6958 SOCK_OPS_GET_FIELD(snd_nxt, snd_nxt, struct tcp_sock); 6959 break; 6960 6961 case offsetof(struct bpf_sock_ops, snd_una): 6962 SOCK_OPS_GET_FIELD(snd_una, snd_una, struct tcp_sock); 6963 break; 6964 6965 case offsetof(struct bpf_sock_ops, mss_cache): 6966 SOCK_OPS_GET_FIELD(mss_cache, mss_cache, struct tcp_sock); 6967 break; 6968 6969 case offsetof(struct bpf_sock_ops, ecn_flags): 6970 SOCK_OPS_GET_FIELD(ecn_flags, ecn_flags, struct tcp_sock); 6971 break; 6972 6973 case offsetof(struct bpf_sock_ops, rate_delivered): 6974 SOCK_OPS_GET_FIELD(rate_delivered, rate_delivered, 6975 struct tcp_sock); 6976 break; 6977 6978 case offsetof(struct bpf_sock_ops, rate_interval_us): 6979 SOCK_OPS_GET_FIELD(rate_interval_us, rate_interval_us, 6980 struct tcp_sock); 6981 break; 6982 6983 case offsetof(struct bpf_sock_ops, packets_out): 6984 SOCK_OPS_GET_FIELD(packets_out, packets_out, struct tcp_sock); 6985 break; 6986 6987 case offsetof(struct bpf_sock_ops, retrans_out): 6988 SOCK_OPS_GET_FIELD(retrans_out, retrans_out, struct tcp_sock); 6989 break; 6990 6991 case offsetof(struct bpf_sock_ops, total_retrans): 6992 SOCK_OPS_GET_FIELD(total_retrans, total_retrans, 6993 struct tcp_sock); 6994 break; 6995 6996 case offsetof(struct bpf_sock_ops, segs_in): 6997 SOCK_OPS_GET_FIELD(segs_in, segs_in, struct tcp_sock); 6998 break; 6999 7000 case offsetof(struct bpf_sock_ops, data_segs_in): 7001 SOCK_OPS_GET_FIELD(data_segs_in, data_segs_in, struct tcp_sock); 7002 break; 7003 7004 case offsetof(struct bpf_sock_ops, segs_out): 7005 SOCK_OPS_GET_FIELD(segs_out, segs_out, struct tcp_sock); 7006 break; 7007 7008 case offsetof(struct bpf_sock_ops, data_segs_out): 7009 SOCK_OPS_GET_FIELD(data_segs_out, data_segs_out, 7010 struct tcp_sock); 7011 break; 7012 7013 case offsetof(struct bpf_sock_ops, lost_out): 7014 SOCK_OPS_GET_FIELD(lost_out, lost_out, struct tcp_sock); 7015 break; 7016 7017 case offsetof(struct bpf_sock_ops, sacked_out): 7018 SOCK_OPS_GET_FIELD(sacked_out, sacked_out, struct tcp_sock); 7019 break; 7020 7021 case offsetof(struct bpf_sock_ops, sk_txhash): 7022 SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash, 7023 struct sock, type); 7024 break; 7025 7026 case offsetof(struct bpf_sock_ops, bytes_received): 7027 SOCK_OPS_GET_FIELD(bytes_received, bytes_received, 7028 struct tcp_sock); 7029 break; 7030 7031 case offsetof(struct bpf_sock_ops, bytes_acked): 7032 SOCK_OPS_GET_FIELD(bytes_acked, bytes_acked, struct tcp_sock); 7033 break; 7034 7035 } 7036 return insn - insn_buf; 7037 } 7038 7039 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type, 7040 const struct bpf_insn *si, 7041 struct bpf_insn *insn_buf, 7042 struct bpf_prog *prog, u32 *target_size) 7043 { 7044 struct bpf_insn *insn = insn_buf; 7045 int off; 7046 7047 switch (si->off) { 7048 case offsetof(struct __sk_buff, data_end): 7049 off = si->off; 7050 off -= offsetof(struct __sk_buff, data_end); 7051 off += offsetof(struct sk_buff, cb); 7052 off += offsetof(struct tcp_skb_cb, bpf.data_end); 7053 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 7054 si->src_reg, off); 7055 break; 7056 default: 7057 return bpf_convert_ctx_access(type, si, insn_buf, prog, 7058 target_size); 7059 } 7060 7061 return insn - insn_buf; 7062 } 7063 7064 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type, 7065 const struct bpf_insn *si, 7066 struct bpf_insn *insn_buf, 7067 struct bpf_prog *prog, u32 *target_size) 7068 { 7069 struct bpf_insn *insn = insn_buf; 7070 #if IS_ENABLED(CONFIG_IPV6) 7071 int off; 7072 #endif 7073 7074 switch (si->off) { 7075 case offsetof(struct sk_msg_md, data): 7076 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data), 7077 si->dst_reg, si->src_reg, 7078 offsetof(struct sk_msg, data)); 7079 break; 7080 case offsetof(struct sk_msg_md, data_end): 7081 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end), 7082 si->dst_reg, si->src_reg, 7083 offsetof(struct sk_msg, data_end)); 7084 break; 7085 case offsetof(struct sk_msg_md, family): 7086 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 7087 7088 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 7089 struct sk_msg, sk), 7090 si->dst_reg, si->src_reg, 7091 offsetof(struct sk_msg, sk)); 7092 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 7093 offsetof(struct sock_common, skc_family)); 7094 break; 7095 7096 case offsetof(struct sk_msg_md, remote_ip4): 7097 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 7098 7099 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 7100 struct sk_msg, sk), 7101 si->dst_reg, si->src_reg, 7102 offsetof(struct sk_msg, sk)); 7103 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 7104 offsetof(struct sock_common, skc_daddr)); 7105 break; 7106 7107 case offsetof(struct sk_msg_md, local_ip4): 7108 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 7109 skc_rcv_saddr) != 4); 7110 7111 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 7112 struct sk_msg, sk), 7113 si->dst_reg, si->src_reg, 7114 offsetof(struct sk_msg, sk)); 7115 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 7116 offsetof(struct sock_common, 7117 skc_rcv_saddr)); 7118 break; 7119 7120 case offsetof(struct sk_msg_md, remote_ip6[0]) ... 7121 offsetof(struct sk_msg_md, remote_ip6[3]): 7122 #if IS_ENABLED(CONFIG_IPV6) 7123 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 7124 skc_v6_daddr.s6_addr32[0]) != 4); 7125 7126 off = si->off; 7127 off -= offsetof(struct sk_msg_md, remote_ip6[0]); 7128 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 7129 struct sk_msg, sk), 7130 si->dst_reg, si->src_reg, 7131 offsetof(struct sk_msg, sk)); 7132 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 7133 offsetof(struct sock_common, 7134 skc_v6_daddr.s6_addr32[0]) + 7135 off); 7136 #else 7137 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 7138 #endif 7139 break; 7140 7141 case offsetof(struct sk_msg_md, local_ip6[0]) ... 7142 offsetof(struct sk_msg_md, local_ip6[3]): 7143 #if IS_ENABLED(CONFIG_IPV6) 7144 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 7145 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 7146 7147 off = si->off; 7148 off -= offsetof(struct sk_msg_md, local_ip6[0]); 7149 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 7150 struct sk_msg, sk), 7151 si->dst_reg, si->src_reg, 7152 offsetof(struct sk_msg, sk)); 7153 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 7154 offsetof(struct sock_common, 7155 skc_v6_rcv_saddr.s6_addr32[0]) + 7156 off); 7157 #else 7158 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 7159 #endif 7160 break; 7161 7162 case offsetof(struct sk_msg_md, remote_port): 7163 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 7164 7165 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 7166 struct sk_msg, sk), 7167 si->dst_reg, si->src_reg, 7168 offsetof(struct sk_msg, sk)); 7169 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 7170 offsetof(struct sock_common, skc_dport)); 7171 #ifndef __BIG_ENDIAN_BITFIELD 7172 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 7173 #endif 7174 break; 7175 7176 case offsetof(struct sk_msg_md, local_port): 7177 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 7178 7179 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 7180 struct sk_msg, sk), 7181 si->dst_reg, si->src_reg, 7182 offsetof(struct sk_msg, sk)); 7183 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 7184 offsetof(struct sock_common, skc_num)); 7185 break; 7186 } 7187 7188 return insn - insn_buf; 7189 } 7190 7191 const struct bpf_verifier_ops sk_filter_verifier_ops = { 7192 .get_func_proto = sk_filter_func_proto, 7193 .is_valid_access = sk_filter_is_valid_access, 7194 .convert_ctx_access = bpf_convert_ctx_access, 7195 .gen_ld_abs = bpf_gen_ld_abs, 7196 }; 7197 7198 const struct bpf_prog_ops sk_filter_prog_ops = { 7199 .test_run = bpf_prog_test_run_skb, 7200 }; 7201 7202 const struct bpf_verifier_ops tc_cls_act_verifier_ops = { 7203 .get_func_proto = tc_cls_act_func_proto, 7204 .is_valid_access = tc_cls_act_is_valid_access, 7205 .convert_ctx_access = tc_cls_act_convert_ctx_access, 7206 .gen_prologue = tc_cls_act_prologue, 7207 .gen_ld_abs = bpf_gen_ld_abs, 7208 }; 7209 7210 const struct bpf_prog_ops tc_cls_act_prog_ops = { 7211 .test_run = bpf_prog_test_run_skb, 7212 }; 7213 7214 const struct bpf_verifier_ops xdp_verifier_ops = { 7215 .get_func_proto = xdp_func_proto, 7216 .is_valid_access = xdp_is_valid_access, 7217 .convert_ctx_access = xdp_convert_ctx_access, 7218 .gen_prologue = bpf_noop_prologue, 7219 }; 7220 7221 const struct bpf_prog_ops xdp_prog_ops = { 7222 .test_run = bpf_prog_test_run_xdp, 7223 }; 7224 7225 const struct bpf_verifier_ops cg_skb_verifier_ops = { 7226 .get_func_proto = cg_skb_func_proto, 7227 .is_valid_access = cg_skb_is_valid_access, 7228 .convert_ctx_access = bpf_convert_ctx_access, 7229 }; 7230 7231 const struct bpf_prog_ops cg_skb_prog_ops = { 7232 .test_run = bpf_prog_test_run_skb, 7233 }; 7234 7235 const struct bpf_verifier_ops lwt_in_verifier_ops = { 7236 .get_func_proto = lwt_in_func_proto, 7237 .is_valid_access = lwt_is_valid_access, 7238 .convert_ctx_access = bpf_convert_ctx_access, 7239 }; 7240 7241 const struct bpf_prog_ops lwt_in_prog_ops = { 7242 .test_run = bpf_prog_test_run_skb, 7243 }; 7244 7245 const struct bpf_verifier_ops lwt_out_verifier_ops = { 7246 .get_func_proto = lwt_out_func_proto, 7247 .is_valid_access = lwt_is_valid_access, 7248 .convert_ctx_access = bpf_convert_ctx_access, 7249 }; 7250 7251 const struct bpf_prog_ops lwt_out_prog_ops = { 7252 .test_run = bpf_prog_test_run_skb, 7253 }; 7254 7255 const struct bpf_verifier_ops lwt_xmit_verifier_ops = { 7256 .get_func_proto = lwt_xmit_func_proto, 7257 .is_valid_access = lwt_is_valid_access, 7258 .convert_ctx_access = bpf_convert_ctx_access, 7259 .gen_prologue = tc_cls_act_prologue, 7260 }; 7261 7262 const struct bpf_prog_ops lwt_xmit_prog_ops = { 7263 .test_run = bpf_prog_test_run_skb, 7264 }; 7265 7266 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = { 7267 .get_func_proto = lwt_seg6local_func_proto, 7268 .is_valid_access = lwt_is_valid_access, 7269 .convert_ctx_access = bpf_convert_ctx_access, 7270 }; 7271 7272 const struct bpf_prog_ops lwt_seg6local_prog_ops = { 7273 .test_run = bpf_prog_test_run_skb, 7274 }; 7275 7276 const struct bpf_verifier_ops cg_sock_verifier_ops = { 7277 .get_func_proto = sock_filter_func_proto, 7278 .is_valid_access = sock_filter_is_valid_access, 7279 .convert_ctx_access = bpf_sock_convert_ctx_access, 7280 }; 7281 7282 const struct bpf_prog_ops cg_sock_prog_ops = { 7283 }; 7284 7285 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = { 7286 .get_func_proto = sock_addr_func_proto, 7287 .is_valid_access = sock_addr_is_valid_access, 7288 .convert_ctx_access = sock_addr_convert_ctx_access, 7289 }; 7290 7291 const struct bpf_prog_ops cg_sock_addr_prog_ops = { 7292 }; 7293 7294 const struct bpf_verifier_ops sock_ops_verifier_ops = { 7295 .get_func_proto = sock_ops_func_proto, 7296 .is_valid_access = sock_ops_is_valid_access, 7297 .convert_ctx_access = sock_ops_convert_ctx_access, 7298 }; 7299 7300 const struct bpf_prog_ops sock_ops_prog_ops = { 7301 }; 7302 7303 const struct bpf_verifier_ops sk_skb_verifier_ops = { 7304 .get_func_proto = sk_skb_func_proto, 7305 .is_valid_access = sk_skb_is_valid_access, 7306 .convert_ctx_access = sk_skb_convert_ctx_access, 7307 .gen_prologue = sk_skb_prologue, 7308 }; 7309 7310 const struct bpf_prog_ops sk_skb_prog_ops = { 7311 }; 7312 7313 const struct bpf_verifier_ops sk_msg_verifier_ops = { 7314 .get_func_proto = sk_msg_func_proto, 7315 .is_valid_access = sk_msg_is_valid_access, 7316 .convert_ctx_access = sk_msg_convert_ctx_access, 7317 .gen_prologue = bpf_noop_prologue, 7318 }; 7319 7320 const struct bpf_prog_ops sk_msg_prog_ops = { 7321 }; 7322 7323 const struct bpf_verifier_ops flow_dissector_verifier_ops = { 7324 .get_func_proto = flow_dissector_func_proto, 7325 .is_valid_access = flow_dissector_is_valid_access, 7326 .convert_ctx_access = bpf_convert_ctx_access, 7327 }; 7328 7329 const struct bpf_prog_ops flow_dissector_prog_ops = { 7330 }; 7331 7332 int sk_detach_filter(struct sock *sk) 7333 { 7334 int ret = -ENOENT; 7335 struct sk_filter *filter; 7336 7337 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 7338 return -EPERM; 7339 7340 filter = rcu_dereference_protected(sk->sk_filter, 7341 lockdep_sock_is_held(sk)); 7342 if (filter) { 7343 RCU_INIT_POINTER(sk->sk_filter, NULL); 7344 sk_filter_uncharge(sk, filter); 7345 ret = 0; 7346 } 7347 7348 return ret; 7349 } 7350 EXPORT_SYMBOL_GPL(sk_detach_filter); 7351 7352 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf, 7353 unsigned int len) 7354 { 7355 struct sock_fprog_kern *fprog; 7356 struct sk_filter *filter; 7357 int ret = 0; 7358 7359 lock_sock(sk); 7360 filter = rcu_dereference_protected(sk->sk_filter, 7361 lockdep_sock_is_held(sk)); 7362 if (!filter) 7363 goto out; 7364 7365 /* We're copying the filter that has been originally attached, 7366 * so no conversion/decode needed anymore. eBPF programs that 7367 * have no original program cannot be dumped through this. 7368 */ 7369 ret = -EACCES; 7370 fprog = filter->prog->orig_prog; 7371 if (!fprog) 7372 goto out; 7373 7374 ret = fprog->len; 7375 if (!len) 7376 /* User space only enquires number of filter blocks. */ 7377 goto out; 7378 7379 ret = -EINVAL; 7380 if (len < fprog->len) 7381 goto out; 7382 7383 ret = -EFAULT; 7384 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog))) 7385 goto out; 7386 7387 /* Instead of bytes, the API requests to return the number 7388 * of filter blocks. 7389 */ 7390 ret = fprog->len; 7391 out: 7392 release_sock(sk); 7393 return ret; 7394 } 7395 7396 #ifdef CONFIG_INET 7397 struct sk_reuseport_kern { 7398 struct sk_buff *skb; 7399 struct sock *sk; 7400 struct sock *selected_sk; 7401 void *data_end; 7402 u32 hash; 7403 u32 reuseport_id; 7404 bool bind_inany; 7405 }; 7406 7407 static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern, 7408 struct sock_reuseport *reuse, 7409 struct sock *sk, struct sk_buff *skb, 7410 u32 hash) 7411 { 7412 reuse_kern->skb = skb; 7413 reuse_kern->sk = sk; 7414 reuse_kern->selected_sk = NULL; 7415 reuse_kern->data_end = skb->data + skb_headlen(skb); 7416 reuse_kern->hash = hash; 7417 reuse_kern->reuseport_id = reuse->reuseport_id; 7418 reuse_kern->bind_inany = reuse->bind_inany; 7419 } 7420 7421 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk, 7422 struct bpf_prog *prog, struct sk_buff *skb, 7423 u32 hash) 7424 { 7425 struct sk_reuseport_kern reuse_kern; 7426 enum sk_action action; 7427 7428 bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, hash); 7429 action = BPF_PROG_RUN(prog, &reuse_kern); 7430 7431 if (action == SK_PASS) 7432 return reuse_kern.selected_sk; 7433 else 7434 return ERR_PTR(-ECONNREFUSED); 7435 } 7436 7437 BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern, 7438 struct bpf_map *, map, void *, key, u32, flags) 7439 { 7440 struct sock_reuseport *reuse; 7441 struct sock *selected_sk; 7442 7443 selected_sk = map->ops->map_lookup_elem(map, key); 7444 if (!selected_sk) 7445 return -ENOENT; 7446 7447 reuse = rcu_dereference(selected_sk->sk_reuseport_cb); 7448 if (!reuse) 7449 /* selected_sk is unhashed (e.g. by close()) after the 7450 * above map_lookup_elem(). Treat selected_sk has already 7451 * been removed from the map. 7452 */ 7453 return -ENOENT; 7454 7455 if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) { 7456 struct sock *sk; 7457 7458 if (unlikely(!reuse_kern->reuseport_id)) 7459 /* There is a small race between adding the 7460 * sk to the map and setting the 7461 * reuse_kern->reuseport_id. 7462 * Treat it as the sk has not been added to 7463 * the bpf map yet. 7464 */ 7465 return -ENOENT; 7466 7467 sk = reuse_kern->sk; 7468 if (sk->sk_protocol != selected_sk->sk_protocol) 7469 return -EPROTOTYPE; 7470 else if (sk->sk_family != selected_sk->sk_family) 7471 return -EAFNOSUPPORT; 7472 7473 /* Catch all. Likely bound to a different sockaddr. */ 7474 return -EBADFD; 7475 } 7476 7477 reuse_kern->selected_sk = selected_sk; 7478 7479 return 0; 7480 } 7481 7482 static const struct bpf_func_proto sk_select_reuseport_proto = { 7483 .func = sk_select_reuseport, 7484 .gpl_only = false, 7485 .ret_type = RET_INTEGER, 7486 .arg1_type = ARG_PTR_TO_CTX, 7487 .arg2_type = ARG_CONST_MAP_PTR, 7488 .arg3_type = ARG_PTR_TO_MAP_KEY, 7489 .arg4_type = ARG_ANYTHING, 7490 }; 7491 7492 BPF_CALL_4(sk_reuseport_load_bytes, 7493 const struct sk_reuseport_kern *, reuse_kern, u32, offset, 7494 void *, to, u32, len) 7495 { 7496 return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len); 7497 } 7498 7499 static const struct bpf_func_proto sk_reuseport_load_bytes_proto = { 7500 .func = sk_reuseport_load_bytes, 7501 .gpl_only = false, 7502 .ret_type = RET_INTEGER, 7503 .arg1_type = ARG_PTR_TO_CTX, 7504 .arg2_type = ARG_ANYTHING, 7505 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 7506 .arg4_type = ARG_CONST_SIZE, 7507 }; 7508 7509 BPF_CALL_5(sk_reuseport_load_bytes_relative, 7510 const struct sk_reuseport_kern *, reuse_kern, u32, offset, 7511 void *, to, u32, len, u32, start_header) 7512 { 7513 return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to, 7514 len, start_header); 7515 } 7516 7517 static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = { 7518 .func = sk_reuseport_load_bytes_relative, 7519 .gpl_only = false, 7520 .ret_type = RET_INTEGER, 7521 .arg1_type = ARG_PTR_TO_CTX, 7522 .arg2_type = ARG_ANYTHING, 7523 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 7524 .arg4_type = ARG_CONST_SIZE, 7525 .arg5_type = ARG_ANYTHING, 7526 }; 7527 7528 static const struct bpf_func_proto * 7529 sk_reuseport_func_proto(enum bpf_func_id func_id, 7530 const struct bpf_prog *prog) 7531 { 7532 switch (func_id) { 7533 case BPF_FUNC_sk_select_reuseport: 7534 return &sk_select_reuseport_proto; 7535 case BPF_FUNC_skb_load_bytes: 7536 return &sk_reuseport_load_bytes_proto; 7537 case BPF_FUNC_skb_load_bytes_relative: 7538 return &sk_reuseport_load_bytes_relative_proto; 7539 default: 7540 return bpf_base_func_proto(func_id); 7541 } 7542 } 7543 7544 static bool 7545 sk_reuseport_is_valid_access(int off, int size, 7546 enum bpf_access_type type, 7547 const struct bpf_prog *prog, 7548 struct bpf_insn_access_aux *info) 7549 { 7550 const u32 size_default = sizeof(__u32); 7551 7552 if (off < 0 || off >= sizeof(struct sk_reuseport_md) || 7553 off % size || type != BPF_READ) 7554 return false; 7555 7556 switch (off) { 7557 case offsetof(struct sk_reuseport_md, data): 7558 info->reg_type = PTR_TO_PACKET; 7559 return size == sizeof(__u64); 7560 7561 case offsetof(struct sk_reuseport_md, data_end): 7562 info->reg_type = PTR_TO_PACKET_END; 7563 return size == sizeof(__u64); 7564 7565 case offsetof(struct sk_reuseport_md, hash): 7566 return size == size_default; 7567 7568 /* Fields that allow narrowing */ 7569 case offsetof(struct sk_reuseport_md, eth_protocol): 7570 if (size < FIELD_SIZEOF(struct sk_buff, protocol)) 7571 return false; 7572 /* fall through */ 7573 case offsetof(struct sk_reuseport_md, ip_protocol): 7574 case offsetof(struct sk_reuseport_md, bind_inany): 7575 case offsetof(struct sk_reuseport_md, len): 7576 bpf_ctx_record_field_size(info, size_default); 7577 return bpf_ctx_narrow_access_ok(off, size, size_default); 7578 7579 default: 7580 return false; 7581 } 7582 } 7583 7584 #define SK_REUSEPORT_LOAD_FIELD(F) ({ \ 7585 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \ 7586 si->dst_reg, si->src_reg, \ 7587 bpf_target_off(struct sk_reuseport_kern, F, \ 7588 FIELD_SIZEOF(struct sk_reuseport_kern, F), \ 7589 target_size)); \ 7590 }) 7591 7592 #define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD) \ 7593 SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern, \ 7594 struct sk_buff, \ 7595 skb, \ 7596 SKB_FIELD) 7597 7598 #define SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(SK_FIELD, BPF_SIZE, EXTRA_OFF) \ 7599 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(struct sk_reuseport_kern, \ 7600 struct sock, \ 7601 sk, \ 7602 SK_FIELD, BPF_SIZE, EXTRA_OFF) 7603 7604 static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type, 7605 const struct bpf_insn *si, 7606 struct bpf_insn *insn_buf, 7607 struct bpf_prog *prog, 7608 u32 *target_size) 7609 { 7610 struct bpf_insn *insn = insn_buf; 7611 7612 switch (si->off) { 7613 case offsetof(struct sk_reuseport_md, data): 7614 SK_REUSEPORT_LOAD_SKB_FIELD(data); 7615 break; 7616 7617 case offsetof(struct sk_reuseport_md, len): 7618 SK_REUSEPORT_LOAD_SKB_FIELD(len); 7619 break; 7620 7621 case offsetof(struct sk_reuseport_md, eth_protocol): 7622 SK_REUSEPORT_LOAD_SKB_FIELD(protocol); 7623 break; 7624 7625 case offsetof(struct sk_reuseport_md, ip_protocol): 7626 BUILD_BUG_ON(HWEIGHT32(SK_FL_PROTO_MASK) != BITS_PER_BYTE); 7627 SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(__sk_flags_offset, 7628 BPF_W, 0); 7629 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK); 7630 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 7631 SK_FL_PROTO_SHIFT); 7632 /* SK_FL_PROTO_MASK and SK_FL_PROTO_SHIFT are endian 7633 * aware. No further narrowing or masking is needed. 7634 */ 7635 *target_size = 1; 7636 break; 7637 7638 case offsetof(struct sk_reuseport_md, data_end): 7639 SK_REUSEPORT_LOAD_FIELD(data_end); 7640 break; 7641 7642 case offsetof(struct sk_reuseport_md, hash): 7643 SK_REUSEPORT_LOAD_FIELD(hash); 7644 break; 7645 7646 case offsetof(struct sk_reuseport_md, bind_inany): 7647 SK_REUSEPORT_LOAD_FIELD(bind_inany); 7648 break; 7649 } 7650 7651 return insn - insn_buf; 7652 } 7653 7654 const struct bpf_verifier_ops sk_reuseport_verifier_ops = { 7655 .get_func_proto = sk_reuseport_func_proto, 7656 .is_valid_access = sk_reuseport_is_valid_access, 7657 .convert_ctx_access = sk_reuseport_convert_ctx_access, 7658 }; 7659 7660 const struct bpf_prog_ops sk_reuseport_prog_ops = { 7661 }; 7662 #endif /* CONFIG_INET */ 7663