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 <net/sock.h> 42 #include <net/flow_dissector.h> 43 #include <linux/errno.h> 44 #include <linux/timer.h> 45 #include <linux/uaccess.h> 46 #include <asm/unaligned.h> 47 #include <asm/cmpxchg.h> 48 #include <linux/filter.h> 49 #include <linux/ratelimit.h> 50 #include <linux/seccomp.h> 51 #include <linux/if_vlan.h> 52 #include <linux/bpf.h> 53 #include <net/sch_generic.h> 54 #include <net/cls_cgroup.h> 55 #include <net/dst_metadata.h> 56 #include <net/dst.h> 57 #include <net/sock_reuseport.h> 58 #include <net/busy_poll.h> 59 #include <net/tcp.h> 60 #include <net/xfrm.h> 61 #include <linux/bpf_trace.h> 62 #include <net/xdp_sock.h> 63 #include <linux/inetdevice.h> 64 #include <net/ip_fib.h> 65 #include <net/flow.h> 66 #include <net/arp.h> 67 #include <net/ipv6.h> 68 #include <linux/seg6_local.h> 69 #include <net/seg6.h> 70 #include <net/seg6_local.h> 71 72 /** 73 * sk_filter_trim_cap - run a packet through a socket filter 74 * @sk: sock associated with &sk_buff 75 * @skb: buffer to filter 76 * @cap: limit on how short the eBPF program may trim the packet 77 * 78 * Run the eBPF program and then cut skb->data to correct size returned by 79 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller 80 * than pkt_len we keep whole skb->data. This is the socket level 81 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should 82 * be accepted or -EPERM if the packet should be tossed. 83 * 84 */ 85 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap) 86 { 87 int err; 88 struct sk_filter *filter; 89 90 /* 91 * If the skb was allocated from pfmemalloc reserves, only 92 * allow SOCK_MEMALLOC sockets to use it as this socket is 93 * helping free memory 94 */ 95 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) { 96 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP); 97 return -ENOMEM; 98 } 99 err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb); 100 if (err) 101 return err; 102 103 err = security_sock_rcv_skb(sk, skb); 104 if (err) 105 return err; 106 107 rcu_read_lock(); 108 filter = rcu_dereference(sk->sk_filter); 109 if (filter) { 110 struct sock *save_sk = skb->sk; 111 unsigned int pkt_len; 112 113 skb->sk = sk; 114 pkt_len = bpf_prog_run_save_cb(filter->prog, skb); 115 skb->sk = save_sk; 116 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM; 117 } 118 rcu_read_unlock(); 119 120 return err; 121 } 122 EXPORT_SYMBOL(sk_filter_trim_cap); 123 124 BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb) 125 { 126 return skb_get_poff(skb); 127 } 128 129 BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x) 130 { 131 struct nlattr *nla; 132 133 if (skb_is_nonlinear(skb)) 134 return 0; 135 136 if (skb->len < sizeof(struct nlattr)) 137 return 0; 138 139 if (a > skb->len - sizeof(struct nlattr)) 140 return 0; 141 142 nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x); 143 if (nla) 144 return (void *) nla - (void *) skb->data; 145 146 return 0; 147 } 148 149 BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x) 150 { 151 struct nlattr *nla; 152 153 if (skb_is_nonlinear(skb)) 154 return 0; 155 156 if (skb->len < sizeof(struct nlattr)) 157 return 0; 158 159 if (a > skb->len - sizeof(struct nlattr)) 160 return 0; 161 162 nla = (struct nlattr *) &skb->data[a]; 163 if (nla->nla_len > skb->len - a) 164 return 0; 165 166 nla = nla_find_nested(nla, x); 167 if (nla) 168 return (void *) nla - (void *) skb->data; 169 170 return 0; 171 } 172 173 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *, 174 data, int, headlen, int, offset) 175 { 176 u8 tmp, *ptr; 177 const int len = sizeof(tmp); 178 179 if (offset >= 0) { 180 if (headlen - offset >= len) 181 return *(u8 *)(data + offset); 182 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp))) 183 return tmp; 184 } else { 185 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len); 186 if (likely(ptr)) 187 return *(u8 *)ptr; 188 } 189 190 return -EFAULT; 191 } 192 193 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb, 194 int, offset) 195 { 196 return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len, 197 offset); 198 } 199 200 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *, 201 data, int, headlen, int, offset) 202 { 203 u16 tmp, *ptr; 204 const int len = sizeof(tmp); 205 206 if (offset >= 0) { 207 if (headlen - offset >= len) 208 return get_unaligned_be16(data + offset); 209 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp))) 210 return be16_to_cpu(tmp); 211 } else { 212 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len); 213 if (likely(ptr)) 214 return get_unaligned_be16(ptr); 215 } 216 217 return -EFAULT; 218 } 219 220 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb, 221 int, offset) 222 { 223 return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len, 224 offset); 225 } 226 227 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *, 228 data, int, headlen, int, offset) 229 { 230 u32 tmp, *ptr; 231 const int len = sizeof(tmp); 232 233 if (likely(offset >= 0)) { 234 if (headlen - offset >= len) 235 return get_unaligned_be32(data + offset); 236 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp))) 237 return be32_to_cpu(tmp); 238 } else { 239 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len); 240 if (likely(ptr)) 241 return get_unaligned_be32(ptr); 242 } 243 244 return -EFAULT; 245 } 246 247 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb, 248 int, offset) 249 { 250 return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len, 251 offset); 252 } 253 254 BPF_CALL_0(bpf_get_raw_cpu_id) 255 { 256 return raw_smp_processor_id(); 257 } 258 259 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = { 260 .func = bpf_get_raw_cpu_id, 261 .gpl_only = false, 262 .ret_type = RET_INTEGER, 263 }; 264 265 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg, 266 struct bpf_insn *insn_buf) 267 { 268 struct bpf_insn *insn = insn_buf; 269 270 switch (skb_field) { 271 case SKF_AD_MARK: 272 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4); 273 274 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, 275 offsetof(struct sk_buff, mark)); 276 break; 277 278 case SKF_AD_PKTTYPE: 279 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET()); 280 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX); 281 #ifdef __BIG_ENDIAN_BITFIELD 282 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5); 283 #endif 284 break; 285 286 case SKF_AD_QUEUE: 287 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2); 288 289 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, 290 offsetof(struct sk_buff, queue_mapping)); 291 break; 292 293 case SKF_AD_VLAN_TAG: 294 case SKF_AD_VLAN_TAG_PRESENT: 295 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2); 296 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); 297 298 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */ 299 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, 300 offsetof(struct sk_buff, vlan_tci)); 301 if (skb_field == SKF_AD_VLAN_TAG) { 302 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 303 ~VLAN_TAG_PRESENT); 304 } else { 305 /* dst_reg >>= 12 */ 306 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12); 307 /* dst_reg &= 1 */ 308 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1); 309 } 310 break; 311 } 312 313 return insn - insn_buf; 314 } 315 316 static bool convert_bpf_extensions(struct sock_filter *fp, 317 struct bpf_insn **insnp) 318 { 319 struct bpf_insn *insn = *insnp; 320 u32 cnt; 321 322 switch (fp->k) { 323 case SKF_AD_OFF + SKF_AD_PROTOCOL: 324 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2); 325 326 /* A = *(u16 *) (CTX + offsetof(protocol)) */ 327 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX, 328 offsetof(struct sk_buff, protocol)); 329 /* A = ntohs(A) [emitting a nop or swap16] */ 330 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16); 331 break; 332 333 case SKF_AD_OFF + SKF_AD_PKTTYPE: 334 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn); 335 insn += cnt - 1; 336 break; 337 338 case SKF_AD_OFF + SKF_AD_IFINDEX: 339 case SKF_AD_OFF + SKF_AD_HATYPE: 340 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4); 341 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2); 342 343 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 344 BPF_REG_TMP, BPF_REG_CTX, 345 offsetof(struct sk_buff, dev)); 346 /* if (tmp != 0) goto pc + 1 */ 347 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1); 348 *insn++ = BPF_EXIT_INSN(); 349 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX) 350 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP, 351 offsetof(struct net_device, ifindex)); 352 else 353 *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP, 354 offsetof(struct net_device, type)); 355 break; 356 357 case SKF_AD_OFF + SKF_AD_MARK: 358 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn); 359 insn += cnt - 1; 360 break; 361 362 case SKF_AD_OFF + SKF_AD_RXHASH: 363 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4); 364 365 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, 366 offsetof(struct sk_buff, hash)); 367 break; 368 369 case SKF_AD_OFF + SKF_AD_QUEUE: 370 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn); 371 insn += cnt - 1; 372 break; 373 374 case SKF_AD_OFF + SKF_AD_VLAN_TAG: 375 cnt = convert_skb_access(SKF_AD_VLAN_TAG, 376 BPF_REG_A, BPF_REG_CTX, insn); 377 insn += cnt - 1; 378 break; 379 380 case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT: 381 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT, 382 BPF_REG_A, BPF_REG_CTX, insn); 383 insn += cnt - 1; 384 break; 385 386 case SKF_AD_OFF + SKF_AD_VLAN_TPID: 387 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2); 388 389 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */ 390 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX, 391 offsetof(struct sk_buff, vlan_proto)); 392 /* A = ntohs(A) [emitting a nop or swap16] */ 393 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16); 394 break; 395 396 case SKF_AD_OFF + SKF_AD_PAY_OFFSET: 397 case SKF_AD_OFF + SKF_AD_NLATTR: 398 case SKF_AD_OFF + SKF_AD_NLATTR_NEST: 399 case SKF_AD_OFF + SKF_AD_CPU: 400 case SKF_AD_OFF + SKF_AD_RANDOM: 401 /* arg1 = CTX */ 402 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX); 403 /* arg2 = A */ 404 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A); 405 /* arg3 = X */ 406 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X); 407 /* Emit call(arg1=CTX, arg2=A, arg3=X) */ 408 switch (fp->k) { 409 case SKF_AD_OFF + SKF_AD_PAY_OFFSET: 410 *insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset); 411 break; 412 case SKF_AD_OFF + SKF_AD_NLATTR: 413 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr); 414 break; 415 case SKF_AD_OFF + SKF_AD_NLATTR_NEST: 416 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest); 417 break; 418 case SKF_AD_OFF + SKF_AD_CPU: 419 *insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id); 420 break; 421 case SKF_AD_OFF + SKF_AD_RANDOM: 422 *insn = BPF_EMIT_CALL(bpf_user_rnd_u32); 423 bpf_user_rnd_init_once(); 424 break; 425 } 426 break; 427 428 case SKF_AD_OFF + SKF_AD_ALU_XOR_X: 429 /* A ^= X */ 430 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X); 431 break; 432 433 default: 434 /* This is just a dummy call to avoid letting the compiler 435 * evict __bpf_call_base() as an optimization. Placed here 436 * where no-one bothers. 437 */ 438 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0); 439 return false; 440 } 441 442 *insnp = insn; 443 return true; 444 } 445 446 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp) 447 { 448 const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS); 449 int size = bpf_size_to_bytes(BPF_SIZE(fp->code)); 450 bool endian = BPF_SIZE(fp->code) == BPF_H || 451 BPF_SIZE(fp->code) == BPF_W; 452 bool indirect = BPF_MODE(fp->code) == BPF_IND; 453 const int ip_align = NET_IP_ALIGN; 454 struct bpf_insn *insn = *insnp; 455 int offset = fp->k; 456 457 if (!indirect && 458 ((unaligned_ok && offset >= 0) || 459 (!unaligned_ok && offset >= 0 && 460 offset + ip_align >= 0 && 461 offset + ip_align % size == 0))) { 462 bool ldx_off_ok = offset <= S16_MAX; 463 464 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H); 465 *insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset); 466 *insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP, 467 size, 2 + endian + (!ldx_off_ok * 2)); 468 if (ldx_off_ok) { 469 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A, 470 BPF_REG_D, offset); 471 } else { 472 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D); 473 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset); 474 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A, 475 BPF_REG_TMP, 0); 476 } 477 if (endian) 478 *insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8); 479 *insn++ = BPF_JMP_A(8); 480 } 481 482 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX); 483 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D); 484 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H); 485 if (!indirect) { 486 *insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset); 487 } else { 488 *insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X); 489 if (fp->k) 490 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset); 491 } 492 493 switch (BPF_SIZE(fp->code)) { 494 case BPF_B: 495 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8); 496 break; 497 case BPF_H: 498 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16); 499 break; 500 case BPF_W: 501 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32); 502 break; 503 default: 504 return false; 505 } 506 507 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2); 508 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 509 *insn = BPF_EXIT_INSN(); 510 511 *insnp = insn; 512 return true; 513 } 514 515 /** 516 * bpf_convert_filter - convert filter program 517 * @prog: the user passed filter program 518 * @len: the length of the user passed filter program 519 * @new_prog: allocated 'struct bpf_prog' or NULL 520 * @new_len: pointer to store length of converted program 521 * @seen_ld_abs: bool whether we've seen ld_abs/ind 522 * 523 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn' 524 * style extended BPF (eBPF). 525 * Conversion workflow: 526 * 527 * 1) First pass for calculating the new program length: 528 * bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs) 529 * 530 * 2) 2nd pass to remap in two passes: 1st pass finds new 531 * jump offsets, 2nd pass remapping: 532 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs) 533 */ 534 static int bpf_convert_filter(struct sock_filter *prog, int len, 535 struct bpf_prog *new_prog, int *new_len, 536 bool *seen_ld_abs) 537 { 538 int new_flen = 0, pass = 0, target, i, stack_off; 539 struct bpf_insn *new_insn, *first_insn = NULL; 540 struct sock_filter *fp; 541 int *addrs = NULL; 542 u8 bpf_src; 543 544 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK); 545 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG); 546 547 if (len <= 0 || len > BPF_MAXINSNS) 548 return -EINVAL; 549 550 if (new_prog) { 551 first_insn = new_prog->insnsi; 552 addrs = kcalloc(len, sizeof(*addrs), 553 GFP_KERNEL | __GFP_NOWARN); 554 if (!addrs) 555 return -ENOMEM; 556 } 557 558 do_pass: 559 new_insn = first_insn; 560 fp = prog; 561 562 /* Classic BPF related prologue emission. */ 563 if (new_prog) { 564 /* Classic BPF expects A and X to be reset first. These need 565 * to be guaranteed to be the first two instructions. 566 */ 567 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 568 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X); 569 570 /* All programs must keep CTX in callee saved BPF_REG_CTX. 571 * In eBPF case it's done by the compiler, here we need to 572 * do this ourself. Initial CTX is present in BPF_REG_ARG1. 573 */ 574 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1); 575 if (*seen_ld_abs) { 576 /* For packet access in classic BPF, cache skb->data 577 * in callee-saved BPF R8 and skb->len - skb->data_len 578 * (headlen) in BPF R9. Since classic BPF is read-only 579 * on CTX, we only need to cache it once. 580 */ 581 *new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data), 582 BPF_REG_D, BPF_REG_CTX, 583 offsetof(struct sk_buff, data)); 584 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX, 585 offsetof(struct sk_buff, len)); 586 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX, 587 offsetof(struct sk_buff, data_len)); 588 *new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP); 589 } 590 } else { 591 new_insn += 3; 592 } 593 594 for (i = 0; i < len; fp++, i++) { 595 struct bpf_insn tmp_insns[32] = { }; 596 struct bpf_insn *insn = tmp_insns; 597 598 if (addrs) 599 addrs[i] = new_insn - first_insn; 600 601 switch (fp->code) { 602 /* All arithmetic insns and skb loads map as-is. */ 603 case BPF_ALU | BPF_ADD | BPF_X: 604 case BPF_ALU | BPF_ADD | BPF_K: 605 case BPF_ALU | BPF_SUB | BPF_X: 606 case BPF_ALU | BPF_SUB | BPF_K: 607 case BPF_ALU | BPF_AND | BPF_X: 608 case BPF_ALU | BPF_AND | BPF_K: 609 case BPF_ALU | BPF_OR | BPF_X: 610 case BPF_ALU | BPF_OR | BPF_K: 611 case BPF_ALU | BPF_LSH | BPF_X: 612 case BPF_ALU | BPF_LSH | BPF_K: 613 case BPF_ALU | BPF_RSH | BPF_X: 614 case BPF_ALU | BPF_RSH | BPF_K: 615 case BPF_ALU | BPF_XOR | BPF_X: 616 case BPF_ALU | BPF_XOR | BPF_K: 617 case BPF_ALU | BPF_MUL | BPF_X: 618 case BPF_ALU | BPF_MUL | BPF_K: 619 case BPF_ALU | BPF_DIV | BPF_X: 620 case BPF_ALU | BPF_DIV | BPF_K: 621 case BPF_ALU | BPF_MOD | BPF_X: 622 case BPF_ALU | BPF_MOD | BPF_K: 623 case BPF_ALU | BPF_NEG: 624 case BPF_LD | BPF_ABS | BPF_W: 625 case BPF_LD | BPF_ABS | BPF_H: 626 case BPF_LD | BPF_ABS | BPF_B: 627 case BPF_LD | BPF_IND | BPF_W: 628 case BPF_LD | BPF_IND | BPF_H: 629 case BPF_LD | BPF_IND | BPF_B: 630 /* Check for overloaded BPF extension and 631 * directly convert it if found, otherwise 632 * just move on with mapping. 633 */ 634 if (BPF_CLASS(fp->code) == BPF_LD && 635 BPF_MODE(fp->code) == BPF_ABS && 636 convert_bpf_extensions(fp, &insn)) 637 break; 638 if (BPF_CLASS(fp->code) == BPF_LD && 639 convert_bpf_ld_abs(fp, &insn)) { 640 *seen_ld_abs = true; 641 break; 642 } 643 644 if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) || 645 fp->code == (BPF_ALU | BPF_MOD | BPF_X)) { 646 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X); 647 /* Error with exception code on div/mod by 0. 648 * For cBPF programs, this was always return 0. 649 */ 650 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2); 651 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 652 *insn++ = BPF_EXIT_INSN(); 653 } 654 655 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k); 656 break; 657 658 /* Jump transformation cannot use BPF block macros 659 * everywhere as offset calculation and target updates 660 * require a bit more work than the rest, i.e. jump 661 * opcodes map as-is, but offsets need adjustment. 662 */ 663 664 #define BPF_EMIT_JMP \ 665 do { \ 666 const s32 off_min = S16_MIN, off_max = S16_MAX; \ 667 s32 off; \ 668 \ 669 if (target >= len || target < 0) \ 670 goto err; \ 671 off = addrs ? addrs[target] - addrs[i] - 1 : 0; \ 672 /* Adjust pc relative offset for 2nd or 3rd insn. */ \ 673 off -= insn - tmp_insns; \ 674 /* Reject anything not fitting into insn->off. */ \ 675 if (off < off_min || off > off_max) \ 676 goto err; \ 677 insn->off = off; \ 678 } while (0) 679 680 case BPF_JMP | BPF_JA: 681 target = i + fp->k + 1; 682 insn->code = fp->code; 683 BPF_EMIT_JMP; 684 break; 685 686 case BPF_JMP | BPF_JEQ | BPF_K: 687 case BPF_JMP | BPF_JEQ | BPF_X: 688 case BPF_JMP | BPF_JSET | BPF_K: 689 case BPF_JMP | BPF_JSET | BPF_X: 690 case BPF_JMP | BPF_JGT | BPF_K: 691 case BPF_JMP | BPF_JGT | BPF_X: 692 case BPF_JMP | BPF_JGE | BPF_K: 693 case BPF_JMP | BPF_JGE | BPF_X: 694 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) { 695 /* BPF immediates are signed, zero extend 696 * immediate into tmp register and use it 697 * in compare insn. 698 */ 699 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k); 700 701 insn->dst_reg = BPF_REG_A; 702 insn->src_reg = BPF_REG_TMP; 703 bpf_src = BPF_X; 704 } else { 705 insn->dst_reg = BPF_REG_A; 706 insn->imm = fp->k; 707 bpf_src = BPF_SRC(fp->code); 708 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0; 709 } 710 711 /* Common case where 'jump_false' is next insn. */ 712 if (fp->jf == 0) { 713 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; 714 target = i + fp->jt + 1; 715 BPF_EMIT_JMP; 716 break; 717 } 718 719 /* Convert some jumps when 'jump_true' is next insn. */ 720 if (fp->jt == 0) { 721 switch (BPF_OP(fp->code)) { 722 case BPF_JEQ: 723 insn->code = BPF_JMP | BPF_JNE | bpf_src; 724 break; 725 case BPF_JGT: 726 insn->code = BPF_JMP | BPF_JLE | bpf_src; 727 break; 728 case BPF_JGE: 729 insn->code = BPF_JMP | BPF_JLT | bpf_src; 730 break; 731 default: 732 goto jmp_rest; 733 } 734 735 target = i + fp->jf + 1; 736 BPF_EMIT_JMP; 737 break; 738 } 739 jmp_rest: 740 /* Other jumps are mapped into two insns: Jxx and JA. */ 741 target = i + fp->jt + 1; 742 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; 743 BPF_EMIT_JMP; 744 insn++; 745 746 insn->code = BPF_JMP | BPF_JA; 747 target = i + fp->jf + 1; 748 BPF_EMIT_JMP; 749 break; 750 751 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */ 752 case BPF_LDX | BPF_MSH | BPF_B: { 753 struct sock_filter tmp = { 754 .code = BPF_LD | BPF_ABS | BPF_B, 755 .k = fp->k, 756 }; 757 758 *seen_ld_abs = true; 759 760 /* X = A */ 761 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 762 /* A = BPF_R0 = *(u8 *) (skb->data + K) */ 763 convert_bpf_ld_abs(&tmp, &insn); 764 insn++; 765 /* A &= 0xf */ 766 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf); 767 /* A <<= 2 */ 768 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2); 769 /* tmp = X */ 770 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X); 771 /* X = A */ 772 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 773 /* A = tmp */ 774 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP); 775 break; 776 } 777 /* RET_K is remaped into 2 insns. RET_A case doesn't need an 778 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A. 779 */ 780 case BPF_RET | BPF_A: 781 case BPF_RET | BPF_K: 782 if (BPF_RVAL(fp->code) == BPF_K) 783 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0, 784 0, fp->k); 785 *insn = BPF_EXIT_INSN(); 786 break; 787 788 /* Store to stack. */ 789 case BPF_ST: 790 case BPF_STX: 791 stack_off = fp->k * 4 + 4; 792 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) == 793 BPF_ST ? BPF_REG_A : BPF_REG_X, 794 -stack_off); 795 /* check_load_and_stores() verifies that classic BPF can 796 * load from stack only after write, so tracking 797 * stack_depth for ST|STX insns is enough 798 */ 799 if (new_prog && new_prog->aux->stack_depth < stack_off) 800 new_prog->aux->stack_depth = stack_off; 801 break; 802 803 /* Load from stack. */ 804 case BPF_LD | BPF_MEM: 805 case BPF_LDX | BPF_MEM: 806 stack_off = fp->k * 4 + 4; 807 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? 808 BPF_REG_A : BPF_REG_X, BPF_REG_FP, 809 -stack_off); 810 break; 811 812 /* A = K or X = K */ 813 case BPF_LD | BPF_IMM: 814 case BPF_LDX | BPF_IMM: 815 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ? 816 BPF_REG_A : BPF_REG_X, fp->k); 817 break; 818 819 /* X = A */ 820 case BPF_MISC | BPF_TAX: 821 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 822 break; 823 824 /* A = X */ 825 case BPF_MISC | BPF_TXA: 826 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X); 827 break; 828 829 /* A = skb->len or X = skb->len */ 830 case BPF_LD | BPF_W | BPF_LEN: 831 case BPF_LDX | BPF_W | BPF_LEN: 832 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? 833 BPF_REG_A : BPF_REG_X, BPF_REG_CTX, 834 offsetof(struct sk_buff, len)); 835 break; 836 837 /* Access seccomp_data fields. */ 838 case BPF_LDX | BPF_ABS | BPF_W: 839 /* A = *(u32 *) (ctx + K) */ 840 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k); 841 break; 842 843 /* Unknown instruction. */ 844 default: 845 goto err; 846 } 847 848 insn++; 849 if (new_prog) 850 memcpy(new_insn, tmp_insns, 851 sizeof(*insn) * (insn - tmp_insns)); 852 new_insn += insn - tmp_insns; 853 } 854 855 if (!new_prog) { 856 /* Only calculating new length. */ 857 *new_len = new_insn - first_insn; 858 if (*seen_ld_abs) 859 *new_len += 4; /* Prologue bits. */ 860 return 0; 861 } 862 863 pass++; 864 if (new_flen != new_insn - first_insn) { 865 new_flen = new_insn - first_insn; 866 if (pass > 2) 867 goto err; 868 goto do_pass; 869 } 870 871 kfree(addrs); 872 BUG_ON(*new_len != new_flen); 873 return 0; 874 err: 875 kfree(addrs); 876 return -EINVAL; 877 } 878 879 /* Security: 880 * 881 * As we dont want to clear mem[] array for each packet going through 882 * __bpf_prog_run(), we check that filter loaded by user never try to read 883 * a cell if not previously written, and we check all branches to be sure 884 * a malicious user doesn't try to abuse us. 885 */ 886 static int check_load_and_stores(const struct sock_filter *filter, int flen) 887 { 888 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */ 889 int pc, ret = 0; 890 891 BUILD_BUG_ON(BPF_MEMWORDS > 16); 892 893 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL); 894 if (!masks) 895 return -ENOMEM; 896 897 memset(masks, 0xff, flen * sizeof(*masks)); 898 899 for (pc = 0; pc < flen; pc++) { 900 memvalid &= masks[pc]; 901 902 switch (filter[pc].code) { 903 case BPF_ST: 904 case BPF_STX: 905 memvalid |= (1 << filter[pc].k); 906 break; 907 case BPF_LD | BPF_MEM: 908 case BPF_LDX | BPF_MEM: 909 if (!(memvalid & (1 << filter[pc].k))) { 910 ret = -EINVAL; 911 goto error; 912 } 913 break; 914 case BPF_JMP | BPF_JA: 915 /* A jump must set masks on target */ 916 masks[pc + 1 + filter[pc].k] &= memvalid; 917 memvalid = ~0; 918 break; 919 case BPF_JMP | BPF_JEQ | BPF_K: 920 case BPF_JMP | BPF_JEQ | BPF_X: 921 case BPF_JMP | BPF_JGE | BPF_K: 922 case BPF_JMP | BPF_JGE | BPF_X: 923 case BPF_JMP | BPF_JGT | BPF_K: 924 case BPF_JMP | BPF_JGT | BPF_X: 925 case BPF_JMP | BPF_JSET | BPF_K: 926 case BPF_JMP | BPF_JSET | BPF_X: 927 /* A jump must set masks on targets */ 928 masks[pc + 1 + filter[pc].jt] &= memvalid; 929 masks[pc + 1 + filter[pc].jf] &= memvalid; 930 memvalid = ~0; 931 break; 932 } 933 } 934 error: 935 kfree(masks); 936 return ret; 937 } 938 939 static bool chk_code_allowed(u16 code_to_probe) 940 { 941 static const bool codes[] = { 942 /* 32 bit ALU operations */ 943 [BPF_ALU | BPF_ADD | BPF_K] = true, 944 [BPF_ALU | BPF_ADD | BPF_X] = true, 945 [BPF_ALU | BPF_SUB | BPF_K] = true, 946 [BPF_ALU | BPF_SUB | BPF_X] = true, 947 [BPF_ALU | BPF_MUL | BPF_K] = true, 948 [BPF_ALU | BPF_MUL | BPF_X] = true, 949 [BPF_ALU | BPF_DIV | BPF_K] = true, 950 [BPF_ALU | BPF_DIV | BPF_X] = true, 951 [BPF_ALU | BPF_MOD | BPF_K] = true, 952 [BPF_ALU | BPF_MOD | BPF_X] = true, 953 [BPF_ALU | BPF_AND | BPF_K] = true, 954 [BPF_ALU | BPF_AND | BPF_X] = true, 955 [BPF_ALU | BPF_OR | BPF_K] = true, 956 [BPF_ALU | BPF_OR | BPF_X] = true, 957 [BPF_ALU | BPF_XOR | BPF_K] = true, 958 [BPF_ALU | BPF_XOR | BPF_X] = true, 959 [BPF_ALU | BPF_LSH | BPF_K] = true, 960 [BPF_ALU | BPF_LSH | BPF_X] = true, 961 [BPF_ALU | BPF_RSH | BPF_K] = true, 962 [BPF_ALU | BPF_RSH | BPF_X] = true, 963 [BPF_ALU | BPF_NEG] = true, 964 /* Load instructions */ 965 [BPF_LD | BPF_W | BPF_ABS] = true, 966 [BPF_LD | BPF_H | BPF_ABS] = true, 967 [BPF_LD | BPF_B | BPF_ABS] = true, 968 [BPF_LD | BPF_W | BPF_LEN] = true, 969 [BPF_LD | BPF_W | BPF_IND] = true, 970 [BPF_LD | BPF_H | BPF_IND] = true, 971 [BPF_LD | BPF_B | BPF_IND] = true, 972 [BPF_LD | BPF_IMM] = true, 973 [BPF_LD | BPF_MEM] = true, 974 [BPF_LDX | BPF_W | BPF_LEN] = true, 975 [BPF_LDX | BPF_B | BPF_MSH] = true, 976 [BPF_LDX | BPF_IMM] = true, 977 [BPF_LDX | BPF_MEM] = true, 978 /* Store instructions */ 979 [BPF_ST] = true, 980 [BPF_STX] = true, 981 /* Misc instructions */ 982 [BPF_MISC | BPF_TAX] = true, 983 [BPF_MISC | BPF_TXA] = true, 984 /* Return instructions */ 985 [BPF_RET | BPF_K] = true, 986 [BPF_RET | BPF_A] = true, 987 /* Jump instructions */ 988 [BPF_JMP | BPF_JA] = true, 989 [BPF_JMP | BPF_JEQ | BPF_K] = true, 990 [BPF_JMP | BPF_JEQ | BPF_X] = true, 991 [BPF_JMP | BPF_JGE | BPF_K] = true, 992 [BPF_JMP | BPF_JGE | BPF_X] = true, 993 [BPF_JMP | BPF_JGT | BPF_K] = true, 994 [BPF_JMP | BPF_JGT | BPF_X] = true, 995 [BPF_JMP | BPF_JSET | BPF_K] = true, 996 [BPF_JMP | BPF_JSET | BPF_X] = true, 997 }; 998 999 if (code_to_probe >= ARRAY_SIZE(codes)) 1000 return false; 1001 1002 return codes[code_to_probe]; 1003 } 1004 1005 static bool bpf_check_basics_ok(const struct sock_filter *filter, 1006 unsigned int flen) 1007 { 1008 if (filter == NULL) 1009 return false; 1010 if (flen == 0 || flen > BPF_MAXINSNS) 1011 return false; 1012 1013 return true; 1014 } 1015 1016 /** 1017 * bpf_check_classic - verify socket filter code 1018 * @filter: filter to verify 1019 * @flen: length of filter 1020 * 1021 * Check the user's filter code. If we let some ugly 1022 * filter code slip through kaboom! The filter must contain 1023 * no references or jumps that are out of range, no illegal 1024 * instructions, and must end with a RET instruction. 1025 * 1026 * All jumps are forward as they are not signed. 1027 * 1028 * Returns 0 if the rule set is legal or -EINVAL if not. 1029 */ 1030 static int bpf_check_classic(const struct sock_filter *filter, 1031 unsigned int flen) 1032 { 1033 bool anc_found; 1034 int pc; 1035 1036 /* Check the filter code now */ 1037 for (pc = 0; pc < flen; pc++) { 1038 const struct sock_filter *ftest = &filter[pc]; 1039 1040 /* May we actually operate on this code? */ 1041 if (!chk_code_allowed(ftest->code)) 1042 return -EINVAL; 1043 1044 /* Some instructions need special checks */ 1045 switch (ftest->code) { 1046 case BPF_ALU | BPF_DIV | BPF_K: 1047 case BPF_ALU | BPF_MOD | BPF_K: 1048 /* Check for division by zero */ 1049 if (ftest->k == 0) 1050 return -EINVAL; 1051 break; 1052 case BPF_ALU | BPF_LSH | BPF_K: 1053 case BPF_ALU | BPF_RSH | BPF_K: 1054 if (ftest->k >= 32) 1055 return -EINVAL; 1056 break; 1057 case BPF_LD | BPF_MEM: 1058 case BPF_LDX | BPF_MEM: 1059 case BPF_ST: 1060 case BPF_STX: 1061 /* Check for invalid memory addresses */ 1062 if (ftest->k >= BPF_MEMWORDS) 1063 return -EINVAL; 1064 break; 1065 case BPF_JMP | BPF_JA: 1066 /* Note, the large ftest->k might cause loops. 1067 * Compare this with conditional jumps below, 1068 * where offsets are limited. --ANK (981016) 1069 */ 1070 if (ftest->k >= (unsigned int)(flen - pc - 1)) 1071 return -EINVAL; 1072 break; 1073 case BPF_JMP | BPF_JEQ | BPF_K: 1074 case BPF_JMP | BPF_JEQ | BPF_X: 1075 case BPF_JMP | BPF_JGE | BPF_K: 1076 case BPF_JMP | BPF_JGE | BPF_X: 1077 case BPF_JMP | BPF_JGT | BPF_K: 1078 case BPF_JMP | BPF_JGT | BPF_X: 1079 case BPF_JMP | BPF_JSET | BPF_K: 1080 case BPF_JMP | BPF_JSET | BPF_X: 1081 /* Both conditionals must be safe */ 1082 if (pc + ftest->jt + 1 >= flen || 1083 pc + ftest->jf + 1 >= flen) 1084 return -EINVAL; 1085 break; 1086 case BPF_LD | BPF_W | BPF_ABS: 1087 case BPF_LD | BPF_H | BPF_ABS: 1088 case BPF_LD | BPF_B | BPF_ABS: 1089 anc_found = false; 1090 if (bpf_anc_helper(ftest) & BPF_ANC) 1091 anc_found = true; 1092 /* Ancillary operation unknown or unsupported */ 1093 if (anc_found == false && ftest->k >= SKF_AD_OFF) 1094 return -EINVAL; 1095 } 1096 } 1097 1098 /* Last instruction must be a RET code */ 1099 switch (filter[flen - 1].code) { 1100 case BPF_RET | BPF_K: 1101 case BPF_RET | BPF_A: 1102 return check_load_and_stores(filter, flen); 1103 } 1104 1105 return -EINVAL; 1106 } 1107 1108 static int bpf_prog_store_orig_filter(struct bpf_prog *fp, 1109 const struct sock_fprog *fprog) 1110 { 1111 unsigned int fsize = bpf_classic_proglen(fprog); 1112 struct sock_fprog_kern *fkprog; 1113 1114 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL); 1115 if (!fp->orig_prog) 1116 return -ENOMEM; 1117 1118 fkprog = fp->orig_prog; 1119 fkprog->len = fprog->len; 1120 1121 fkprog->filter = kmemdup(fp->insns, fsize, 1122 GFP_KERNEL | __GFP_NOWARN); 1123 if (!fkprog->filter) { 1124 kfree(fp->orig_prog); 1125 return -ENOMEM; 1126 } 1127 1128 return 0; 1129 } 1130 1131 static void bpf_release_orig_filter(struct bpf_prog *fp) 1132 { 1133 struct sock_fprog_kern *fprog = fp->orig_prog; 1134 1135 if (fprog) { 1136 kfree(fprog->filter); 1137 kfree(fprog); 1138 } 1139 } 1140 1141 static void __bpf_prog_release(struct bpf_prog *prog) 1142 { 1143 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) { 1144 bpf_prog_put(prog); 1145 } else { 1146 bpf_release_orig_filter(prog); 1147 bpf_prog_free(prog); 1148 } 1149 } 1150 1151 static void __sk_filter_release(struct sk_filter *fp) 1152 { 1153 __bpf_prog_release(fp->prog); 1154 kfree(fp); 1155 } 1156 1157 /** 1158 * sk_filter_release_rcu - Release a socket filter by rcu_head 1159 * @rcu: rcu_head that contains the sk_filter to free 1160 */ 1161 static void sk_filter_release_rcu(struct rcu_head *rcu) 1162 { 1163 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu); 1164 1165 __sk_filter_release(fp); 1166 } 1167 1168 /** 1169 * sk_filter_release - release a socket filter 1170 * @fp: filter to remove 1171 * 1172 * Remove a filter from a socket and release its resources. 1173 */ 1174 static void sk_filter_release(struct sk_filter *fp) 1175 { 1176 if (refcount_dec_and_test(&fp->refcnt)) 1177 call_rcu(&fp->rcu, sk_filter_release_rcu); 1178 } 1179 1180 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) 1181 { 1182 u32 filter_size = bpf_prog_size(fp->prog->len); 1183 1184 atomic_sub(filter_size, &sk->sk_omem_alloc); 1185 sk_filter_release(fp); 1186 } 1187 1188 /* try to charge the socket memory if there is space available 1189 * return true on success 1190 */ 1191 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1192 { 1193 u32 filter_size = bpf_prog_size(fp->prog->len); 1194 1195 /* same check as in sock_kmalloc() */ 1196 if (filter_size <= sysctl_optmem_max && 1197 atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) { 1198 atomic_add(filter_size, &sk->sk_omem_alloc); 1199 return true; 1200 } 1201 return false; 1202 } 1203 1204 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1205 { 1206 if (!refcount_inc_not_zero(&fp->refcnt)) 1207 return false; 1208 1209 if (!__sk_filter_charge(sk, fp)) { 1210 sk_filter_release(fp); 1211 return false; 1212 } 1213 return true; 1214 } 1215 1216 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp) 1217 { 1218 struct sock_filter *old_prog; 1219 struct bpf_prog *old_fp; 1220 int err, new_len, old_len = fp->len; 1221 bool seen_ld_abs = false; 1222 1223 /* We are free to overwrite insns et al right here as it 1224 * won't be used at this point in time anymore internally 1225 * after the migration to the internal BPF instruction 1226 * representation. 1227 */ 1228 BUILD_BUG_ON(sizeof(struct sock_filter) != 1229 sizeof(struct bpf_insn)); 1230 1231 /* Conversion cannot happen on overlapping memory areas, 1232 * so we need to keep the user BPF around until the 2nd 1233 * pass. At this time, the user BPF is stored in fp->insns. 1234 */ 1235 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter), 1236 GFP_KERNEL | __GFP_NOWARN); 1237 if (!old_prog) { 1238 err = -ENOMEM; 1239 goto out_err; 1240 } 1241 1242 /* 1st pass: calculate the new program length. */ 1243 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len, 1244 &seen_ld_abs); 1245 if (err) 1246 goto out_err_free; 1247 1248 /* Expand fp for appending the new filter representation. */ 1249 old_fp = fp; 1250 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0); 1251 if (!fp) { 1252 /* The old_fp is still around in case we couldn't 1253 * allocate new memory, so uncharge on that one. 1254 */ 1255 fp = old_fp; 1256 err = -ENOMEM; 1257 goto out_err_free; 1258 } 1259 1260 fp->len = new_len; 1261 1262 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */ 1263 err = bpf_convert_filter(old_prog, old_len, fp, &new_len, 1264 &seen_ld_abs); 1265 if (err) 1266 /* 2nd bpf_convert_filter() can fail only if it fails 1267 * to allocate memory, remapping must succeed. Note, 1268 * that at this time old_fp has already been released 1269 * by krealloc(). 1270 */ 1271 goto out_err_free; 1272 1273 fp = bpf_prog_select_runtime(fp, &err); 1274 if (err) 1275 goto out_err_free; 1276 1277 kfree(old_prog); 1278 return fp; 1279 1280 out_err_free: 1281 kfree(old_prog); 1282 out_err: 1283 __bpf_prog_release(fp); 1284 return ERR_PTR(err); 1285 } 1286 1287 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp, 1288 bpf_aux_classic_check_t trans) 1289 { 1290 int err; 1291 1292 fp->bpf_func = NULL; 1293 fp->jited = 0; 1294 1295 err = bpf_check_classic(fp->insns, fp->len); 1296 if (err) { 1297 __bpf_prog_release(fp); 1298 return ERR_PTR(err); 1299 } 1300 1301 /* There might be additional checks and transformations 1302 * needed on classic filters, f.e. in case of seccomp. 1303 */ 1304 if (trans) { 1305 err = trans(fp->insns, fp->len); 1306 if (err) { 1307 __bpf_prog_release(fp); 1308 return ERR_PTR(err); 1309 } 1310 } 1311 1312 /* Probe if we can JIT compile the filter and if so, do 1313 * the compilation of the filter. 1314 */ 1315 bpf_jit_compile(fp); 1316 1317 /* JIT compiler couldn't process this filter, so do the 1318 * internal BPF translation for the optimized interpreter. 1319 */ 1320 if (!fp->jited) 1321 fp = bpf_migrate_filter(fp); 1322 1323 return fp; 1324 } 1325 1326 /** 1327 * bpf_prog_create - create an unattached filter 1328 * @pfp: the unattached filter that is created 1329 * @fprog: the filter program 1330 * 1331 * Create a filter independent of any socket. We first run some 1332 * sanity checks on it to make sure it does not explode on us later. 1333 * If an error occurs or there is insufficient memory for the filter 1334 * a negative errno code is returned. On success the return is zero. 1335 */ 1336 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog) 1337 { 1338 unsigned int fsize = bpf_classic_proglen(fprog); 1339 struct bpf_prog *fp; 1340 1341 /* Make sure new filter is there and in the right amounts. */ 1342 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1343 return -EINVAL; 1344 1345 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1346 if (!fp) 1347 return -ENOMEM; 1348 1349 memcpy(fp->insns, fprog->filter, fsize); 1350 1351 fp->len = fprog->len; 1352 /* Since unattached filters are not copied back to user 1353 * space through sk_get_filter(), we do not need to hold 1354 * a copy here, and can spare us the work. 1355 */ 1356 fp->orig_prog = NULL; 1357 1358 /* bpf_prepare_filter() already takes care of freeing 1359 * memory in case something goes wrong. 1360 */ 1361 fp = bpf_prepare_filter(fp, NULL); 1362 if (IS_ERR(fp)) 1363 return PTR_ERR(fp); 1364 1365 *pfp = fp; 1366 return 0; 1367 } 1368 EXPORT_SYMBOL_GPL(bpf_prog_create); 1369 1370 /** 1371 * bpf_prog_create_from_user - create an unattached filter from user buffer 1372 * @pfp: the unattached filter that is created 1373 * @fprog: the filter program 1374 * @trans: post-classic verifier transformation handler 1375 * @save_orig: save classic BPF program 1376 * 1377 * This function effectively does the same as bpf_prog_create(), only 1378 * that it builds up its insns buffer from user space provided buffer. 1379 * It also allows for passing a bpf_aux_classic_check_t handler. 1380 */ 1381 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 1382 bpf_aux_classic_check_t trans, bool save_orig) 1383 { 1384 unsigned int fsize = bpf_classic_proglen(fprog); 1385 struct bpf_prog *fp; 1386 int err; 1387 1388 /* Make sure new filter is there and in the right amounts. */ 1389 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1390 return -EINVAL; 1391 1392 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1393 if (!fp) 1394 return -ENOMEM; 1395 1396 if (copy_from_user(fp->insns, fprog->filter, fsize)) { 1397 __bpf_prog_free(fp); 1398 return -EFAULT; 1399 } 1400 1401 fp->len = fprog->len; 1402 fp->orig_prog = NULL; 1403 1404 if (save_orig) { 1405 err = bpf_prog_store_orig_filter(fp, fprog); 1406 if (err) { 1407 __bpf_prog_free(fp); 1408 return -ENOMEM; 1409 } 1410 } 1411 1412 /* bpf_prepare_filter() already takes care of freeing 1413 * memory in case something goes wrong. 1414 */ 1415 fp = bpf_prepare_filter(fp, trans); 1416 if (IS_ERR(fp)) 1417 return PTR_ERR(fp); 1418 1419 *pfp = fp; 1420 return 0; 1421 } 1422 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user); 1423 1424 void bpf_prog_destroy(struct bpf_prog *fp) 1425 { 1426 __bpf_prog_release(fp); 1427 } 1428 EXPORT_SYMBOL_GPL(bpf_prog_destroy); 1429 1430 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk) 1431 { 1432 struct sk_filter *fp, *old_fp; 1433 1434 fp = kmalloc(sizeof(*fp), GFP_KERNEL); 1435 if (!fp) 1436 return -ENOMEM; 1437 1438 fp->prog = prog; 1439 1440 if (!__sk_filter_charge(sk, fp)) { 1441 kfree(fp); 1442 return -ENOMEM; 1443 } 1444 refcount_set(&fp->refcnt, 1); 1445 1446 old_fp = rcu_dereference_protected(sk->sk_filter, 1447 lockdep_sock_is_held(sk)); 1448 rcu_assign_pointer(sk->sk_filter, fp); 1449 1450 if (old_fp) 1451 sk_filter_uncharge(sk, old_fp); 1452 1453 return 0; 1454 } 1455 1456 static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk) 1457 { 1458 struct bpf_prog *old_prog; 1459 int err; 1460 1461 if (bpf_prog_size(prog->len) > sysctl_optmem_max) 1462 return -ENOMEM; 1463 1464 if (sk_unhashed(sk) && sk->sk_reuseport) { 1465 err = reuseport_alloc(sk); 1466 if (err) 1467 return err; 1468 } else if (!rcu_access_pointer(sk->sk_reuseport_cb)) { 1469 /* The socket wasn't bound with SO_REUSEPORT */ 1470 return -EINVAL; 1471 } 1472 1473 old_prog = reuseport_attach_prog(sk, prog); 1474 if (old_prog) 1475 bpf_prog_destroy(old_prog); 1476 1477 return 0; 1478 } 1479 1480 static 1481 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk) 1482 { 1483 unsigned int fsize = bpf_classic_proglen(fprog); 1484 struct bpf_prog *prog; 1485 int err; 1486 1487 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 1488 return ERR_PTR(-EPERM); 1489 1490 /* Make sure new filter is there and in the right amounts. */ 1491 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1492 return ERR_PTR(-EINVAL); 1493 1494 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1495 if (!prog) 1496 return ERR_PTR(-ENOMEM); 1497 1498 if (copy_from_user(prog->insns, fprog->filter, fsize)) { 1499 __bpf_prog_free(prog); 1500 return ERR_PTR(-EFAULT); 1501 } 1502 1503 prog->len = fprog->len; 1504 1505 err = bpf_prog_store_orig_filter(prog, fprog); 1506 if (err) { 1507 __bpf_prog_free(prog); 1508 return ERR_PTR(-ENOMEM); 1509 } 1510 1511 /* bpf_prepare_filter() already takes care of freeing 1512 * memory in case something goes wrong. 1513 */ 1514 return bpf_prepare_filter(prog, NULL); 1515 } 1516 1517 /** 1518 * sk_attach_filter - attach a socket filter 1519 * @fprog: the filter program 1520 * @sk: the socket to use 1521 * 1522 * Attach the user's filter code. We first run some sanity checks on 1523 * it to make sure it does not explode on us later. If an error 1524 * occurs or there is insufficient memory for the filter a negative 1525 * errno code is returned. On success the return is zero. 1526 */ 1527 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk) 1528 { 1529 struct bpf_prog *prog = __get_filter(fprog, sk); 1530 int err; 1531 1532 if (IS_ERR(prog)) 1533 return PTR_ERR(prog); 1534 1535 err = __sk_attach_prog(prog, sk); 1536 if (err < 0) { 1537 __bpf_prog_release(prog); 1538 return err; 1539 } 1540 1541 return 0; 1542 } 1543 EXPORT_SYMBOL_GPL(sk_attach_filter); 1544 1545 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk) 1546 { 1547 struct bpf_prog *prog = __get_filter(fprog, sk); 1548 int err; 1549 1550 if (IS_ERR(prog)) 1551 return PTR_ERR(prog); 1552 1553 err = __reuseport_attach_prog(prog, sk); 1554 if (err < 0) { 1555 __bpf_prog_release(prog); 1556 return err; 1557 } 1558 1559 return 0; 1560 } 1561 1562 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk) 1563 { 1564 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 1565 return ERR_PTR(-EPERM); 1566 1567 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER); 1568 } 1569 1570 int sk_attach_bpf(u32 ufd, struct sock *sk) 1571 { 1572 struct bpf_prog *prog = __get_bpf(ufd, sk); 1573 int err; 1574 1575 if (IS_ERR(prog)) 1576 return PTR_ERR(prog); 1577 1578 err = __sk_attach_prog(prog, sk); 1579 if (err < 0) { 1580 bpf_prog_put(prog); 1581 return err; 1582 } 1583 1584 return 0; 1585 } 1586 1587 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk) 1588 { 1589 struct bpf_prog *prog = __get_bpf(ufd, sk); 1590 int err; 1591 1592 if (IS_ERR(prog)) 1593 return PTR_ERR(prog); 1594 1595 err = __reuseport_attach_prog(prog, sk); 1596 if (err < 0) { 1597 bpf_prog_put(prog); 1598 return err; 1599 } 1600 1601 return 0; 1602 } 1603 1604 struct bpf_scratchpad { 1605 union { 1606 __be32 diff[MAX_BPF_STACK / sizeof(__be32)]; 1607 u8 buff[MAX_BPF_STACK]; 1608 }; 1609 }; 1610 1611 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp); 1612 1613 static inline int __bpf_try_make_writable(struct sk_buff *skb, 1614 unsigned int write_len) 1615 { 1616 return skb_ensure_writable(skb, write_len); 1617 } 1618 1619 static inline int bpf_try_make_writable(struct sk_buff *skb, 1620 unsigned int write_len) 1621 { 1622 int err = __bpf_try_make_writable(skb, write_len); 1623 1624 bpf_compute_data_pointers(skb); 1625 return err; 1626 } 1627 1628 static int bpf_try_make_head_writable(struct sk_buff *skb) 1629 { 1630 return bpf_try_make_writable(skb, skb_headlen(skb)); 1631 } 1632 1633 static inline void bpf_push_mac_rcsum(struct sk_buff *skb) 1634 { 1635 if (skb_at_tc_ingress(skb)) 1636 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len); 1637 } 1638 1639 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb) 1640 { 1641 if (skb_at_tc_ingress(skb)) 1642 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len); 1643 } 1644 1645 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset, 1646 const void *, from, u32, len, u64, flags) 1647 { 1648 void *ptr; 1649 1650 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH))) 1651 return -EINVAL; 1652 if (unlikely(offset > 0xffff)) 1653 return -EFAULT; 1654 if (unlikely(bpf_try_make_writable(skb, offset + len))) 1655 return -EFAULT; 1656 1657 ptr = skb->data + offset; 1658 if (flags & BPF_F_RECOMPUTE_CSUM) 1659 __skb_postpull_rcsum(skb, ptr, len, offset); 1660 1661 memcpy(ptr, from, len); 1662 1663 if (flags & BPF_F_RECOMPUTE_CSUM) 1664 __skb_postpush_rcsum(skb, ptr, len, offset); 1665 if (flags & BPF_F_INVALIDATE_HASH) 1666 skb_clear_hash(skb); 1667 1668 return 0; 1669 } 1670 1671 static const struct bpf_func_proto bpf_skb_store_bytes_proto = { 1672 .func = bpf_skb_store_bytes, 1673 .gpl_only = false, 1674 .ret_type = RET_INTEGER, 1675 .arg1_type = ARG_PTR_TO_CTX, 1676 .arg2_type = ARG_ANYTHING, 1677 .arg3_type = ARG_PTR_TO_MEM, 1678 .arg4_type = ARG_CONST_SIZE, 1679 .arg5_type = ARG_ANYTHING, 1680 }; 1681 1682 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset, 1683 void *, to, u32, len) 1684 { 1685 void *ptr; 1686 1687 if (unlikely(offset > 0xffff)) 1688 goto err_clear; 1689 1690 ptr = skb_header_pointer(skb, offset, len, to); 1691 if (unlikely(!ptr)) 1692 goto err_clear; 1693 if (ptr != to) 1694 memcpy(to, ptr, len); 1695 1696 return 0; 1697 err_clear: 1698 memset(to, 0, len); 1699 return -EFAULT; 1700 } 1701 1702 static const struct bpf_func_proto bpf_skb_load_bytes_proto = { 1703 .func = bpf_skb_load_bytes, 1704 .gpl_only = false, 1705 .ret_type = RET_INTEGER, 1706 .arg1_type = ARG_PTR_TO_CTX, 1707 .arg2_type = ARG_ANYTHING, 1708 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 1709 .arg4_type = ARG_CONST_SIZE, 1710 }; 1711 1712 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb, 1713 u32, offset, void *, to, u32, len, u32, start_header) 1714 { 1715 u8 *end = skb_tail_pointer(skb); 1716 u8 *net = skb_network_header(skb); 1717 u8 *mac = skb_mac_header(skb); 1718 u8 *ptr; 1719 1720 if (unlikely(offset > 0xffff || len > (end - mac))) 1721 goto err_clear; 1722 1723 switch (start_header) { 1724 case BPF_HDR_START_MAC: 1725 ptr = mac + offset; 1726 break; 1727 case BPF_HDR_START_NET: 1728 ptr = net + offset; 1729 break; 1730 default: 1731 goto err_clear; 1732 } 1733 1734 if (likely(ptr >= mac && ptr + len <= end)) { 1735 memcpy(to, ptr, len); 1736 return 0; 1737 } 1738 1739 err_clear: 1740 memset(to, 0, len); 1741 return -EFAULT; 1742 } 1743 1744 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = { 1745 .func = bpf_skb_load_bytes_relative, 1746 .gpl_only = false, 1747 .ret_type = RET_INTEGER, 1748 .arg1_type = ARG_PTR_TO_CTX, 1749 .arg2_type = ARG_ANYTHING, 1750 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 1751 .arg4_type = ARG_CONST_SIZE, 1752 .arg5_type = ARG_ANYTHING, 1753 }; 1754 1755 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len) 1756 { 1757 /* Idea is the following: should the needed direct read/write 1758 * test fail during runtime, we can pull in more data and redo 1759 * again, since implicitly, we invalidate previous checks here. 1760 * 1761 * Or, since we know how much we need to make read/writeable, 1762 * this can be done once at the program beginning for direct 1763 * access case. By this we overcome limitations of only current 1764 * headroom being accessible. 1765 */ 1766 return bpf_try_make_writable(skb, len ? : skb_headlen(skb)); 1767 } 1768 1769 static const struct bpf_func_proto bpf_skb_pull_data_proto = { 1770 .func = bpf_skb_pull_data, 1771 .gpl_only = false, 1772 .ret_type = RET_INTEGER, 1773 .arg1_type = ARG_PTR_TO_CTX, 1774 .arg2_type = ARG_ANYTHING, 1775 }; 1776 1777 static inline int sk_skb_try_make_writable(struct sk_buff *skb, 1778 unsigned int write_len) 1779 { 1780 int err = __bpf_try_make_writable(skb, write_len); 1781 1782 bpf_compute_data_end_sk_skb(skb); 1783 return err; 1784 } 1785 1786 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len) 1787 { 1788 /* Idea is the following: should the needed direct read/write 1789 * test fail during runtime, we can pull in more data and redo 1790 * again, since implicitly, we invalidate previous checks here. 1791 * 1792 * Or, since we know how much we need to make read/writeable, 1793 * this can be done once at the program beginning for direct 1794 * access case. By this we overcome limitations of only current 1795 * headroom being accessible. 1796 */ 1797 return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb)); 1798 } 1799 1800 static const struct bpf_func_proto sk_skb_pull_data_proto = { 1801 .func = sk_skb_pull_data, 1802 .gpl_only = false, 1803 .ret_type = RET_INTEGER, 1804 .arg1_type = ARG_PTR_TO_CTX, 1805 .arg2_type = ARG_ANYTHING, 1806 }; 1807 1808 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset, 1809 u64, from, u64, to, u64, flags) 1810 { 1811 __sum16 *ptr; 1812 1813 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK))) 1814 return -EINVAL; 1815 if (unlikely(offset > 0xffff || offset & 1)) 1816 return -EFAULT; 1817 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) 1818 return -EFAULT; 1819 1820 ptr = (__sum16 *)(skb->data + offset); 1821 switch (flags & BPF_F_HDR_FIELD_MASK) { 1822 case 0: 1823 if (unlikely(from != 0)) 1824 return -EINVAL; 1825 1826 csum_replace_by_diff(ptr, to); 1827 break; 1828 case 2: 1829 csum_replace2(ptr, from, to); 1830 break; 1831 case 4: 1832 csum_replace4(ptr, from, to); 1833 break; 1834 default: 1835 return -EINVAL; 1836 } 1837 1838 return 0; 1839 } 1840 1841 static const struct bpf_func_proto bpf_l3_csum_replace_proto = { 1842 .func = bpf_l3_csum_replace, 1843 .gpl_only = false, 1844 .ret_type = RET_INTEGER, 1845 .arg1_type = ARG_PTR_TO_CTX, 1846 .arg2_type = ARG_ANYTHING, 1847 .arg3_type = ARG_ANYTHING, 1848 .arg4_type = ARG_ANYTHING, 1849 .arg5_type = ARG_ANYTHING, 1850 }; 1851 1852 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset, 1853 u64, from, u64, to, u64, flags) 1854 { 1855 bool is_pseudo = flags & BPF_F_PSEUDO_HDR; 1856 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0; 1857 bool do_mforce = flags & BPF_F_MARK_ENFORCE; 1858 __sum16 *ptr; 1859 1860 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE | 1861 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK))) 1862 return -EINVAL; 1863 if (unlikely(offset > 0xffff || offset & 1)) 1864 return -EFAULT; 1865 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) 1866 return -EFAULT; 1867 1868 ptr = (__sum16 *)(skb->data + offset); 1869 if (is_mmzero && !do_mforce && !*ptr) 1870 return 0; 1871 1872 switch (flags & BPF_F_HDR_FIELD_MASK) { 1873 case 0: 1874 if (unlikely(from != 0)) 1875 return -EINVAL; 1876 1877 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo); 1878 break; 1879 case 2: 1880 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo); 1881 break; 1882 case 4: 1883 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo); 1884 break; 1885 default: 1886 return -EINVAL; 1887 } 1888 1889 if (is_mmzero && !*ptr) 1890 *ptr = CSUM_MANGLED_0; 1891 return 0; 1892 } 1893 1894 static const struct bpf_func_proto bpf_l4_csum_replace_proto = { 1895 .func = bpf_l4_csum_replace, 1896 .gpl_only = false, 1897 .ret_type = RET_INTEGER, 1898 .arg1_type = ARG_PTR_TO_CTX, 1899 .arg2_type = ARG_ANYTHING, 1900 .arg3_type = ARG_ANYTHING, 1901 .arg4_type = ARG_ANYTHING, 1902 .arg5_type = ARG_ANYTHING, 1903 }; 1904 1905 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size, 1906 __be32 *, to, u32, to_size, __wsum, seed) 1907 { 1908 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp); 1909 u32 diff_size = from_size + to_size; 1910 int i, j = 0; 1911 1912 /* This is quite flexible, some examples: 1913 * 1914 * from_size == 0, to_size > 0, seed := csum --> pushing data 1915 * from_size > 0, to_size == 0, seed := csum --> pulling data 1916 * from_size > 0, to_size > 0, seed := 0 --> diffing data 1917 * 1918 * Even for diffing, from_size and to_size don't need to be equal. 1919 */ 1920 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) || 1921 diff_size > sizeof(sp->diff))) 1922 return -EINVAL; 1923 1924 for (i = 0; i < from_size / sizeof(__be32); i++, j++) 1925 sp->diff[j] = ~from[i]; 1926 for (i = 0; i < to_size / sizeof(__be32); i++, j++) 1927 sp->diff[j] = to[i]; 1928 1929 return csum_partial(sp->diff, diff_size, seed); 1930 } 1931 1932 static const struct bpf_func_proto bpf_csum_diff_proto = { 1933 .func = bpf_csum_diff, 1934 .gpl_only = false, 1935 .pkt_access = true, 1936 .ret_type = RET_INTEGER, 1937 .arg1_type = ARG_PTR_TO_MEM_OR_NULL, 1938 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 1939 .arg3_type = ARG_PTR_TO_MEM_OR_NULL, 1940 .arg4_type = ARG_CONST_SIZE_OR_ZERO, 1941 .arg5_type = ARG_ANYTHING, 1942 }; 1943 1944 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum) 1945 { 1946 /* The interface is to be used in combination with bpf_csum_diff() 1947 * for direct packet writes. csum rotation for alignment as well 1948 * as emulating csum_sub() can be done from the eBPF program. 1949 */ 1950 if (skb->ip_summed == CHECKSUM_COMPLETE) 1951 return (skb->csum = csum_add(skb->csum, csum)); 1952 1953 return -ENOTSUPP; 1954 } 1955 1956 static const struct bpf_func_proto bpf_csum_update_proto = { 1957 .func = bpf_csum_update, 1958 .gpl_only = false, 1959 .ret_type = RET_INTEGER, 1960 .arg1_type = ARG_PTR_TO_CTX, 1961 .arg2_type = ARG_ANYTHING, 1962 }; 1963 1964 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb) 1965 { 1966 return dev_forward_skb(dev, skb); 1967 } 1968 1969 static inline int __bpf_rx_skb_no_mac(struct net_device *dev, 1970 struct sk_buff *skb) 1971 { 1972 int ret = ____dev_forward_skb(dev, skb); 1973 1974 if (likely(!ret)) { 1975 skb->dev = dev; 1976 ret = netif_rx(skb); 1977 } 1978 1979 return ret; 1980 } 1981 1982 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) 1983 { 1984 int ret; 1985 1986 if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) { 1987 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n"); 1988 kfree_skb(skb); 1989 return -ENETDOWN; 1990 } 1991 1992 skb->dev = dev; 1993 1994 __this_cpu_inc(xmit_recursion); 1995 ret = dev_queue_xmit(skb); 1996 __this_cpu_dec(xmit_recursion); 1997 1998 return ret; 1999 } 2000 2001 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev, 2002 u32 flags) 2003 { 2004 /* skb->mac_len is not set on normal egress */ 2005 unsigned int mlen = skb->network_header - skb->mac_header; 2006 2007 __skb_pull(skb, mlen); 2008 2009 /* At ingress, the mac header has already been pulled once. 2010 * At egress, skb_pospull_rcsum has to be done in case that 2011 * the skb is originated from ingress (i.e. a forwarded skb) 2012 * to ensure that rcsum starts at net header. 2013 */ 2014 if (!skb_at_tc_ingress(skb)) 2015 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen); 2016 skb_pop_mac_header(skb); 2017 skb_reset_mac_len(skb); 2018 return flags & BPF_F_INGRESS ? 2019 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb); 2020 } 2021 2022 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev, 2023 u32 flags) 2024 { 2025 /* Verify that a link layer header is carried */ 2026 if (unlikely(skb->mac_header >= skb->network_header)) { 2027 kfree_skb(skb); 2028 return -ERANGE; 2029 } 2030 2031 bpf_push_mac_rcsum(skb); 2032 return flags & BPF_F_INGRESS ? 2033 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb); 2034 } 2035 2036 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev, 2037 u32 flags) 2038 { 2039 if (dev_is_mac_header_xmit(dev)) 2040 return __bpf_redirect_common(skb, dev, flags); 2041 else 2042 return __bpf_redirect_no_mac(skb, dev, flags); 2043 } 2044 2045 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags) 2046 { 2047 struct net_device *dev; 2048 struct sk_buff *clone; 2049 int ret; 2050 2051 if (unlikely(flags & ~(BPF_F_INGRESS))) 2052 return -EINVAL; 2053 2054 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex); 2055 if (unlikely(!dev)) 2056 return -EINVAL; 2057 2058 clone = skb_clone(skb, GFP_ATOMIC); 2059 if (unlikely(!clone)) 2060 return -ENOMEM; 2061 2062 /* For direct write, we need to keep the invariant that the skbs 2063 * we're dealing with need to be uncloned. Should uncloning fail 2064 * here, we need to free the just generated clone to unclone once 2065 * again. 2066 */ 2067 ret = bpf_try_make_head_writable(skb); 2068 if (unlikely(ret)) { 2069 kfree_skb(clone); 2070 return -ENOMEM; 2071 } 2072 2073 return __bpf_redirect(clone, dev, flags); 2074 } 2075 2076 static const struct bpf_func_proto bpf_clone_redirect_proto = { 2077 .func = bpf_clone_redirect, 2078 .gpl_only = false, 2079 .ret_type = RET_INTEGER, 2080 .arg1_type = ARG_PTR_TO_CTX, 2081 .arg2_type = ARG_ANYTHING, 2082 .arg3_type = ARG_ANYTHING, 2083 }; 2084 2085 struct redirect_info { 2086 u32 ifindex; 2087 u32 flags; 2088 struct bpf_map *map; 2089 struct bpf_map *map_to_flush; 2090 unsigned long map_owner; 2091 }; 2092 2093 static DEFINE_PER_CPU(struct redirect_info, redirect_info); 2094 2095 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags) 2096 { 2097 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 2098 2099 if (unlikely(flags & ~(BPF_F_INGRESS))) 2100 return TC_ACT_SHOT; 2101 2102 ri->ifindex = ifindex; 2103 ri->flags = flags; 2104 2105 return TC_ACT_REDIRECT; 2106 } 2107 2108 int skb_do_redirect(struct sk_buff *skb) 2109 { 2110 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 2111 struct net_device *dev; 2112 2113 dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex); 2114 ri->ifindex = 0; 2115 if (unlikely(!dev)) { 2116 kfree_skb(skb); 2117 return -EINVAL; 2118 } 2119 2120 return __bpf_redirect(skb, dev, ri->flags); 2121 } 2122 2123 static const struct bpf_func_proto bpf_redirect_proto = { 2124 .func = bpf_redirect, 2125 .gpl_only = false, 2126 .ret_type = RET_INTEGER, 2127 .arg1_type = ARG_ANYTHING, 2128 .arg2_type = ARG_ANYTHING, 2129 }; 2130 2131 BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb, 2132 struct bpf_map *, map, void *, key, u64, flags) 2133 { 2134 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); 2135 2136 /* If user passes invalid input drop the packet. */ 2137 if (unlikely(flags & ~(BPF_F_INGRESS))) 2138 return SK_DROP; 2139 2140 tcb->bpf.flags = flags; 2141 tcb->bpf.sk_redir = __sock_hash_lookup_elem(map, key); 2142 if (!tcb->bpf.sk_redir) 2143 return SK_DROP; 2144 2145 return SK_PASS; 2146 } 2147 2148 static const struct bpf_func_proto bpf_sk_redirect_hash_proto = { 2149 .func = bpf_sk_redirect_hash, 2150 .gpl_only = false, 2151 .ret_type = RET_INTEGER, 2152 .arg1_type = ARG_PTR_TO_CTX, 2153 .arg2_type = ARG_CONST_MAP_PTR, 2154 .arg3_type = ARG_PTR_TO_MAP_KEY, 2155 .arg4_type = ARG_ANYTHING, 2156 }; 2157 2158 BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb, 2159 struct bpf_map *, map, u32, key, u64, flags) 2160 { 2161 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); 2162 2163 /* If user passes invalid input drop the packet. */ 2164 if (unlikely(flags & ~(BPF_F_INGRESS))) 2165 return SK_DROP; 2166 2167 tcb->bpf.flags = flags; 2168 tcb->bpf.sk_redir = __sock_map_lookup_elem(map, key); 2169 if (!tcb->bpf.sk_redir) 2170 return SK_DROP; 2171 2172 return SK_PASS; 2173 } 2174 2175 struct sock *do_sk_redirect_map(struct sk_buff *skb) 2176 { 2177 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); 2178 2179 return tcb->bpf.sk_redir; 2180 } 2181 2182 static const struct bpf_func_proto bpf_sk_redirect_map_proto = { 2183 .func = bpf_sk_redirect_map, 2184 .gpl_only = false, 2185 .ret_type = RET_INTEGER, 2186 .arg1_type = ARG_PTR_TO_CTX, 2187 .arg2_type = ARG_CONST_MAP_PTR, 2188 .arg3_type = ARG_ANYTHING, 2189 .arg4_type = ARG_ANYTHING, 2190 }; 2191 2192 BPF_CALL_4(bpf_msg_redirect_hash, struct sk_msg_buff *, msg, 2193 struct bpf_map *, map, void *, key, u64, flags) 2194 { 2195 /* If user passes invalid input drop the packet. */ 2196 if (unlikely(flags & ~(BPF_F_INGRESS))) 2197 return SK_DROP; 2198 2199 msg->flags = flags; 2200 msg->sk_redir = __sock_hash_lookup_elem(map, key); 2201 if (!msg->sk_redir) 2202 return SK_DROP; 2203 2204 return SK_PASS; 2205 } 2206 2207 static const struct bpf_func_proto bpf_msg_redirect_hash_proto = { 2208 .func = bpf_msg_redirect_hash, 2209 .gpl_only = false, 2210 .ret_type = RET_INTEGER, 2211 .arg1_type = ARG_PTR_TO_CTX, 2212 .arg2_type = ARG_CONST_MAP_PTR, 2213 .arg3_type = ARG_PTR_TO_MAP_KEY, 2214 .arg4_type = ARG_ANYTHING, 2215 }; 2216 2217 BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg_buff *, msg, 2218 struct bpf_map *, map, u32, key, u64, flags) 2219 { 2220 /* If user passes invalid input drop the packet. */ 2221 if (unlikely(flags & ~(BPF_F_INGRESS))) 2222 return SK_DROP; 2223 2224 msg->flags = flags; 2225 msg->sk_redir = __sock_map_lookup_elem(map, key); 2226 if (!msg->sk_redir) 2227 return SK_DROP; 2228 2229 return SK_PASS; 2230 } 2231 2232 struct sock *do_msg_redirect_map(struct sk_msg_buff *msg) 2233 { 2234 return msg->sk_redir; 2235 } 2236 2237 static const struct bpf_func_proto bpf_msg_redirect_map_proto = { 2238 .func = bpf_msg_redirect_map, 2239 .gpl_only = false, 2240 .ret_type = RET_INTEGER, 2241 .arg1_type = ARG_PTR_TO_CTX, 2242 .arg2_type = ARG_CONST_MAP_PTR, 2243 .arg3_type = ARG_ANYTHING, 2244 .arg4_type = ARG_ANYTHING, 2245 }; 2246 2247 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg_buff *, msg, u32, bytes) 2248 { 2249 msg->apply_bytes = bytes; 2250 return 0; 2251 } 2252 2253 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = { 2254 .func = bpf_msg_apply_bytes, 2255 .gpl_only = false, 2256 .ret_type = RET_INTEGER, 2257 .arg1_type = ARG_PTR_TO_CTX, 2258 .arg2_type = ARG_ANYTHING, 2259 }; 2260 2261 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg_buff *, msg, u32, bytes) 2262 { 2263 msg->cork_bytes = bytes; 2264 return 0; 2265 } 2266 2267 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = { 2268 .func = bpf_msg_cork_bytes, 2269 .gpl_only = false, 2270 .ret_type = RET_INTEGER, 2271 .arg1_type = ARG_PTR_TO_CTX, 2272 .arg2_type = ARG_ANYTHING, 2273 }; 2274 2275 BPF_CALL_4(bpf_msg_pull_data, 2276 struct sk_msg_buff *, msg, u32, start, u32, end, u64, flags) 2277 { 2278 unsigned int len = 0, offset = 0, copy = 0; 2279 struct scatterlist *sg = msg->sg_data; 2280 int first_sg, last_sg, i, shift; 2281 unsigned char *p, *to, *from; 2282 int bytes = end - start; 2283 struct page *page; 2284 2285 if (unlikely(flags || end <= start)) 2286 return -EINVAL; 2287 2288 /* First find the starting scatterlist element */ 2289 i = msg->sg_start; 2290 do { 2291 len = sg[i].length; 2292 offset += len; 2293 if (start < offset + len) 2294 break; 2295 i++; 2296 if (i == MAX_SKB_FRAGS) 2297 i = 0; 2298 } while (i != msg->sg_end); 2299 2300 if (unlikely(start >= offset + len)) 2301 return -EINVAL; 2302 2303 if (!msg->sg_copy[i] && bytes <= len) 2304 goto out; 2305 2306 first_sg = i; 2307 2308 /* At this point we need to linearize multiple scatterlist 2309 * elements or a single shared page. Either way we need to 2310 * copy into a linear buffer exclusively owned by BPF. Then 2311 * place the buffer in the scatterlist and fixup the original 2312 * entries by removing the entries now in the linear buffer 2313 * and shifting the remaining entries. For now we do not try 2314 * to copy partial entries to avoid complexity of running out 2315 * of sg_entry slots. The downside is reading a single byte 2316 * will copy the entire sg entry. 2317 */ 2318 do { 2319 copy += sg[i].length; 2320 i++; 2321 if (i == MAX_SKB_FRAGS) 2322 i = 0; 2323 if (bytes < copy) 2324 break; 2325 } while (i != msg->sg_end); 2326 last_sg = i; 2327 2328 if (unlikely(copy < end - start)) 2329 return -EINVAL; 2330 2331 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC, get_order(copy)); 2332 if (unlikely(!page)) 2333 return -ENOMEM; 2334 p = page_address(page); 2335 offset = 0; 2336 2337 i = first_sg; 2338 do { 2339 from = sg_virt(&sg[i]); 2340 len = sg[i].length; 2341 to = p + offset; 2342 2343 memcpy(to, from, len); 2344 offset += len; 2345 sg[i].length = 0; 2346 put_page(sg_page(&sg[i])); 2347 2348 i++; 2349 if (i == MAX_SKB_FRAGS) 2350 i = 0; 2351 } while (i != last_sg); 2352 2353 sg[first_sg].length = copy; 2354 sg_set_page(&sg[first_sg], page, copy, 0); 2355 2356 /* To repair sg ring we need to shift entries. If we only 2357 * had a single entry though we can just replace it and 2358 * be done. Otherwise walk the ring and shift the entries. 2359 */ 2360 shift = last_sg - first_sg - 1; 2361 if (!shift) 2362 goto out; 2363 2364 i = first_sg + 1; 2365 do { 2366 int move_from; 2367 2368 if (i + shift >= MAX_SKB_FRAGS) 2369 move_from = i + shift - MAX_SKB_FRAGS; 2370 else 2371 move_from = i + shift; 2372 2373 if (move_from == msg->sg_end) 2374 break; 2375 2376 sg[i] = sg[move_from]; 2377 sg[move_from].length = 0; 2378 sg[move_from].page_link = 0; 2379 sg[move_from].offset = 0; 2380 2381 i++; 2382 if (i == MAX_SKB_FRAGS) 2383 i = 0; 2384 } while (1); 2385 msg->sg_end -= shift; 2386 if (msg->sg_end < 0) 2387 msg->sg_end += MAX_SKB_FRAGS; 2388 out: 2389 msg->data = sg_virt(&sg[i]) + start - offset; 2390 msg->data_end = msg->data + bytes; 2391 2392 return 0; 2393 } 2394 2395 static const struct bpf_func_proto bpf_msg_pull_data_proto = { 2396 .func = bpf_msg_pull_data, 2397 .gpl_only = false, 2398 .ret_type = RET_INTEGER, 2399 .arg1_type = ARG_PTR_TO_CTX, 2400 .arg2_type = ARG_ANYTHING, 2401 .arg3_type = ARG_ANYTHING, 2402 .arg4_type = ARG_ANYTHING, 2403 }; 2404 2405 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb) 2406 { 2407 return task_get_classid(skb); 2408 } 2409 2410 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = { 2411 .func = bpf_get_cgroup_classid, 2412 .gpl_only = false, 2413 .ret_type = RET_INTEGER, 2414 .arg1_type = ARG_PTR_TO_CTX, 2415 }; 2416 2417 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb) 2418 { 2419 return dst_tclassid(skb); 2420 } 2421 2422 static const struct bpf_func_proto bpf_get_route_realm_proto = { 2423 .func = bpf_get_route_realm, 2424 .gpl_only = false, 2425 .ret_type = RET_INTEGER, 2426 .arg1_type = ARG_PTR_TO_CTX, 2427 }; 2428 2429 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb) 2430 { 2431 /* If skb_clear_hash() was called due to mangling, we can 2432 * trigger SW recalculation here. Later access to hash 2433 * can then use the inline skb->hash via context directly 2434 * instead of calling this helper again. 2435 */ 2436 return skb_get_hash(skb); 2437 } 2438 2439 static const struct bpf_func_proto bpf_get_hash_recalc_proto = { 2440 .func = bpf_get_hash_recalc, 2441 .gpl_only = false, 2442 .ret_type = RET_INTEGER, 2443 .arg1_type = ARG_PTR_TO_CTX, 2444 }; 2445 2446 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb) 2447 { 2448 /* After all direct packet write, this can be used once for 2449 * triggering a lazy recalc on next skb_get_hash() invocation. 2450 */ 2451 skb_clear_hash(skb); 2452 return 0; 2453 } 2454 2455 static const struct bpf_func_proto bpf_set_hash_invalid_proto = { 2456 .func = bpf_set_hash_invalid, 2457 .gpl_only = false, 2458 .ret_type = RET_INTEGER, 2459 .arg1_type = ARG_PTR_TO_CTX, 2460 }; 2461 2462 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash) 2463 { 2464 /* Set user specified hash as L4(+), so that it gets returned 2465 * on skb_get_hash() call unless BPF prog later on triggers a 2466 * skb_clear_hash(). 2467 */ 2468 __skb_set_sw_hash(skb, hash, true); 2469 return 0; 2470 } 2471 2472 static const struct bpf_func_proto bpf_set_hash_proto = { 2473 .func = bpf_set_hash, 2474 .gpl_only = false, 2475 .ret_type = RET_INTEGER, 2476 .arg1_type = ARG_PTR_TO_CTX, 2477 .arg2_type = ARG_ANYTHING, 2478 }; 2479 2480 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto, 2481 u16, vlan_tci) 2482 { 2483 int ret; 2484 2485 if (unlikely(vlan_proto != htons(ETH_P_8021Q) && 2486 vlan_proto != htons(ETH_P_8021AD))) 2487 vlan_proto = htons(ETH_P_8021Q); 2488 2489 bpf_push_mac_rcsum(skb); 2490 ret = skb_vlan_push(skb, vlan_proto, vlan_tci); 2491 bpf_pull_mac_rcsum(skb); 2492 2493 bpf_compute_data_pointers(skb); 2494 return ret; 2495 } 2496 2497 static const struct bpf_func_proto bpf_skb_vlan_push_proto = { 2498 .func = bpf_skb_vlan_push, 2499 .gpl_only = false, 2500 .ret_type = RET_INTEGER, 2501 .arg1_type = ARG_PTR_TO_CTX, 2502 .arg2_type = ARG_ANYTHING, 2503 .arg3_type = ARG_ANYTHING, 2504 }; 2505 2506 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb) 2507 { 2508 int ret; 2509 2510 bpf_push_mac_rcsum(skb); 2511 ret = skb_vlan_pop(skb); 2512 bpf_pull_mac_rcsum(skb); 2513 2514 bpf_compute_data_pointers(skb); 2515 return ret; 2516 } 2517 2518 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = { 2519 .func = bpf_skb_vlan_pop, 2520 .gpl_only = false, 2521 .ret_type = RET_INTEGER, 2522 .arg1_type = ARG_PTR_TO_CTX, 2523 }; 2524 2525 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len) 2526 { 2527 /* Caller already did skb_cow() with len as headroom, 2528 * so no need to do it here. 2529 */ 2530 skb_push(skb, len); 2531 memmove(skb->data, skb->data + len, off); 2532 memset(skb->data + off, 0, len); 2533 2534 /* No skb_postpush_rcsum(skb, skb->data + off, len) 2535 * needed here as it does not change the skb->csum 2536 * result for checksum complete when summing over 2537 * zeroed blocks. 2538 */ 2539 return 0; 2540 } 2541 2542 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len) 2543 { 2544 /* skb_ensure_writable() is not needed here, as we're 2545 * already working on an uncloned skb. 2546 */ 2547 if (unlikely(!pskb_may_pull(skb, off + len))) 2548 return -ENOMEM; 2549 2550 skb_postpull_rcsum(skb, skb->data + off, len); 2551 memmove(skb->data + len, skb->data, off); 2552 __skb_pull(skb, len); 2553 2554 return 0; 2555 } 2556 2557 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len) 2558 { 2559 bool trans_same = skb->transport_header == skb->network_header; 2560 int ret; 2561 2562 /* There's no need for __skb_push()/__skb_pull() pair to 2563 * get to the start of the mac header as we're guaranteed 2564 * to always start from here under eBPF. 2565 */ 2566 ret = bpf_skb_generic_push(skb, off, len); 2567 if (likely(!ret)) { 2568 skb->mac_header -= len; 2569 skb->network_header -= len; 2570 if (trans_same) 2571 skb->transport_header = skb->network_header; 2572 } 2573 2574 return ret; 2575 } 2576 2577 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len) 2578 { 2579 bool trans_same = skb->transport_header == skb->network_header; 2580 int ret; 2581 2582 /* Same here, __skb_push()/__skb_pull() pair not needed. */ 2583 ret = bpf_skb_generic_pop(skb, off, len); 2584 if (likely(!ret)) { 2585 skb->mac_header += len; 2586 skb->network_header += len; 2587 if (trans_same) 2588 skb->transport_header = skb->network_header; 2589 } 2590 2591 return ret; 2592 } 2593 2594 static int bpf_skb_proto_4_to_6(struct sk_buff *skb) 2595 { 2596 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); 2597 u32 off = skb_mac_header_len(skb); 2598 int ret; 2599 2600 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2601 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2602 return -ENOTSUPP; 2603 2604 ret = skb_cow(skb, len_diff); 2605 if (unlikely(ret < 0)) 2606 return ret; 2607 2608 ret = bpf_skb_net_hdr_push(skb, off, len_diff); 2609 if (unlikely(ret < 0)) 2610 return ret; 2611 2612 if (skb_is_gso(skb)) { 2613 struct skb_shared_info *shinfo = skb_shinfo(skb); 2614 2615 /* SKB_GSO_TCPV4 needs to be changed into 2616 * SKB_GSO_TCPV6. 2617 */ 2618 if (shinfo->gso_type & SKB_GSO_TCPV4) { 2619 shinfo->gso_type &= ~SKB_GSO_TCPV4; 2620 shinfo->gso_type |= SKB_GSO_TCPV6; 2621 } 2622 2623 /* Due to IPv6 header, MSS needs to be downgraded. */ 2624 skb_decrease_gso_size(shinfo, len_diff); 2625 /* Header must be checked, and gso_segs recomputed. */ 2626 shinfo->gso_type |= SKB_GSO_DODGY; 2627 shinfo->gso_segs = 0; 2628 } 2629 2630 skb->protocol = htons(ETH_P_IPV6); 2631 skb_clear_hash(skb); 2632 2633 return 0; 2634 } 2635 2636 static int bpf_skb_proto_6_to_4(struct sk_buff *skb) 2637 { 2638 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); 2639 u32 off = skb_mac_header_len(skb); 2640 int ret; 2641 2642 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2643 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2644 return -ENOTSUPP; 2645 2646 ret = skb_unclone(skb, GFP_ATOMIC); 2647 if (unlikely(ret < 0)) 2648 return ret; 2649 2650 ret = bpf_skb_net_hdr_pop(skb, off, len_diff); 2651 if (unlikely(ret < 0)) 2652 return ret; 2653 2654 if (skb_is_gso(skb)) { 2655 struct skb_shared_info *shinfo = skb_shinfo(skb); 2656 2657 /* SKB_GSO_TCPV6 needs to be changed into 2658 * SKB_GSO_TCPV4. 2659 */ 2660 if (shinfo->gso_type & SKB_GSO_TCPV6) { 2661 shinfo->gso_type &= ~SKB_GSO_TCPV6; 2662 shinfo->gso_type |= SKB_GSO_TCPV4; 2663 } 2664 2665 /* Due to IPv4 header, MSS can be upgraded. */ 2666 skb_increase_gso_size(shinfo, len_diff); 2667 /* Header must be checked, and gso_segs recomputed. */ 2668 shinfo->gso_type |= SKB_GSO_DODGY; 2669 shinfo->gso_segs = 0; 2670 } 2671 2672 skb->protocol = htons(ETH_P_IP); 2673 skb_clear_hash(skb); 2674 2675 return 0; 2676 } 2677 2678 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto) 2679 { 2680 __be16 from_proto = skb->protocol; 2681 2682 if (from_proto == htons(ETH_P_IP) && 2683 to_proto == htons(ETH_P_IPV6)) 2684 return bpf_skb_proto_4_to_6(skb); 2685 2686 if (from_proto == htons(ETH_P_IPV6) && 2687 to_proto == htons(ETH_P_IP)) 2688 return bpf_skb_proto_6_to_4(skb); 2689 2690 return -ENOTSUPP; 2691 } 2692 2693 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto, 2694 u64, flags) 2695 { 2696 int ret; 2697 2698 if (unlikely(flags)) 2699 return -EINVAL; 2700 2701 /* General idea is that this helper does the basic groundwork 2702 * needed for changing the protocol, and eBPF program fills the 2703 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace() 2704 * and other helpers, rather than passing a raw buffer here. 2705 * 2706 * The rationale is to keep this minimal and without a need to 2707 * deal with raw packet data. F.e. even if we would pass buffers 2708 * here, the program still needs to call the bpf_lX_csum_replace() 2709 * helpers anyway. Plus, this way we keep also separation of 2710 * concerns, since f.e. bpf_skb_store_bytes() should only take 2711 * care of stores. 2712 * 2713 * Currently, additional options and extension header space are 2714 * not supported, but flags register is reserved so we can adapt 2715 * that. For offloads, we mark packet as dodgy, so that headers 2716 * need to be verified first. 2717 */ 2718 ret = bpf_skb_proto_xlat(skb, proto); 2719 bpf_compute_data_pointers(skb); 2720 return ret; 2721 } 2722 2723 static const struct bpf_func_proto bpf_skb_change_proto_proto = { 2724 .func = bpf_skb_change_proto, 2725 .gpl_only = false, 2726 .ret_type = RET_INTEGER, 2727 .arg1_type = ARG_PTR_TO_CTX, 2728 .arg2_type = ARG_ANYTHING, 2729 .arg3_type = ARG_ANYTHING, 2730 }; 2731 2732 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type) 2733 { 2734 /* We only allow a restricted subset to be changed for now. */ 2735 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) || 2736 !skb_pkt_type_ok(pkt_type))) 2737 return -EINVAL; 2738 2739 skb->pkt_type = pkt_type; 2740 return 0; 2741 } 2742 2743 static const struct bpf_func_proto bpf_skb_change_type_proto = { 2744 .func = bpf_skb_change_type, 2745 .gpl_only = false, 2746 .ret_type = RET_INTEGER, 2747 .arg1_type = ARG_PTR_TO_CTX, 2748 .arg2_type = ARG_ANYTHING, 2749 }; 2750 2751 static u32 bpf_skb_net_base_len(const struct sk_buff *skb) 2752 { 2753 switch (skb->protocol) { 2754 case htons(ETH_P_IP): 2755 return sizeof(struct iphdr); 2756 case htons(ETH_P_IPV6): 2757 return sizeof(struct ipv6hdr); 2758 default: 2759 return ~0U; 2760 } 2761 } 2762 2763 static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff) 2764 { 2765 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); 2766 int ret; 2767 2768 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2769 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2770 return -ENOTSUPP; 2771 2772 ret = skb_cow(skb, len_diff); 2773 if (unlikely(ret < 0)) 2774 return ret; 2775 2776 ret = bpf_skb_net_hdr_push(skb, off, len_diff); 2777 if (unlikely(ret < 0)) 2778 return ret; 2779 2780 if (skb_is_gso(skb)) { 2781 struct skb_shared_info *shinfo = skb_shinfo(skb); 2782 2783 /* Due to header grow, MSS needs to be downgraded. */ 2784 skb_decrease_gso_size(shinfo, len_diff); 2785 /* Header must be checked, and gso_segs recomputed. */ 2786 shinfo->gso_type |= SKB_GSO_DODGY; 2787 shinfo->gso_segs = 0; 2788 } 2789 2790 return 0; 2791 } 2792 2793 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff) 2794 { 2795 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); 2796 int ret; 2797 2798 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2799 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2800 return -ENOTSUPP; 2801 2802 ret = skb_unclone(skb, GFP_ATOMIC); 2803 if (unlikely(ret < 0)) 2804 return ret; 2805 2806 ret = bpf_skb_net_hdr_pop(skb, off, len_diff); 2807 if (unlikely(ret < 0)) 2808 return ret; 2809 2810 if (skb_is_gso(skb)) { 2811 struct skb_shared_info *shinfo = skb_shinfo(skb); 2812 2813 /* Due to header shrink, MSS can be upgraded. */ 2814 skb_increase_gso_size(shinfo, len_diff); 2815 /* Header must be checked, and gso_segs recomputed. */ 2816 shinfo->gso_type |= SKB_GSO_DODGY; 2817 shinfo->gso_segs = 0; 2818 } 2819 2820 return 0; 2821 } 2822 2823 static u32 __bpf_skb_max_len(const struct sk_buff *skb) 2824 { 2825 return skb->dev ? skb->dev->mtu + skb->dev->hard_header_len : 2826 SKB_MAX_ALLOC; 2827 } 2828 2829 static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff) 2830 { 2831 bool trans_same = skb->transport_header == skb->network_header; 2832 u32 len_cur, len_diff_abs = abs(len_diff); 2833 u32 len_min = bpf_skb_net_base_len(skb); 2834 u32 len_max = __bpf_skb_max_len(skb); 2835 __be16 proto = skb->protocol; 2836 bool shrink = len_diff < 0; 2837 int ret; 2838 2839 if (unlikely(len_diff_abs > 0xfffU)) 2840 return -EFAULT; 2841 if (unlikely(proto != htons(ETH_P_IP) && 2842 proto != htons(ETH_P_IPV6))) 2843 return -ENOTSUPP; 2844 2845 len_cur = skb->len - skb_network_offset(skb); 2846 if (skb_transport_header_was_set(skb) && !trans_same) 2847 len_cur = skb_network_header_len(skb); 2848 if ((shrink && (len_diff_abs >= len_cur || 2849 len_cur - len_diff_abs < len_min)) || 2850 (!shrink && (skb->len + len_diff_abs > len_max && 2851 !skb_is_gso(skb)))) 2852 return -ENOTSUPP; 2853 2854 ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) : 2855 bpf_skb_net_grow(skb, len_diff_abs); 2856 2857 bpf_compute_data_pointers(skb); 2858 return ret; 2859 } 2860 2861 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff, 2862 u32, mode, u64, flags) 2863 { 2864 if (unlikely(flags)) 2865 return -EINVAL; 2866 if (likely(mode == BPF_ADJ_ROOM_NET)) 2867 return bpf_skb_adjust_net(skb, len_diff); 2868 2869 return -ENOTSUPP; 2870 } 2871 2872 static const struct bpf_func_proto bpf_skb_adjust_room_proto = { 2873 .func = bpf_skb_adjust_room, 2874 .gpl_only = false, 2875 .ret_type = RET_INTEGER, 2876 .arg1_type = ARG_PTR_TO_CTX, 2877 .arg2_type = ARG_ANYTHING, 2878 .arg3_type = ARG_ANYTHING, 2879 .arg4_type = ARG_ANYTHING, 2880 }; 2881 2882 static u32 __bpf_skb_min_len(const struct sk_buff *skb) 2883 { 2884 u32 min_len = skb_network_offset(skb); 2885 2886 if (skb_transport_header_was_set(skb)) 2887 min_len = skb_transport_offset(skb); 2888 if (skb->ip_summed == CHECKSUM_PARTIAL) 2889 min_len = skb_checksum_start_offset(skb) + 2890 skb->csum_offset + sizeof(__sum16); 2891 return min_len; 2892 } 2893 2894 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len) 2895 { 2896 unsigned int old_len = skb->len; 2897 int ret; 2898 2899 ret = __skb_grow_rcsum(skb, new_len); 2900 if (!ret) 2901 memset(skb->data + old_len, 0, new_len - old_len); 2902 return ret; 2903 } 2904 2905 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len) 2906 { 2907 return __skb_trim_rcsum(skb, new_len); 2908 } 2909 2910 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len, 2911 u64 flags) 2912 { 2913 u32 max_len = __bpf_skb_max_len(skb); 2914 u32 min_len = __bpf_skb_min_len(skb); 2915 int ret; 2916 2917 if (unlikely(flags || new_len > max_len || new_len < min_len)) 2918 return -EINVAL; 2919 if (skb->encapsulation) 2920 return -ENOTSUPP; 2921 2922 /* The basic idea of this helper is that it's performing the 2923 * needed work to either grow or trim an skb, and eBPF program 2924 * rewrites the rest via helpers like bpf_skb_store_bytes(), 2925 * bpf_lX_csum_replace() and others rather than passing a raw 2926 * buffer here. This one is a slow path helper and intended 2927 * for replies with control messages. 2928 * 2929 * Like in bpf_skb_change_proto(), we want to keep this rather 2930 * minimal and without protocol specifics so that we are able 2931 * to separate concerns as in bpf_skb_store_bytes() should only 2932 * be the one responsible for writing buffers. 2933 * 2934 * It's really expected to be a slow path operation here for 2935 * control message replies, so we're implicitly linearizing, 2936 * uncloning and drop offloads from the skb by this. 2937 */ 2938 ret = __bpf_try_make_writable(skb, skb->len); 2939 if (!ret) { 2940 if (new_len > skb->len) 2941 ret = bpf_skb_grow_rcsum(skb, new_len); 2942 else if (new_len < skb->len) 2943 ret = bpf_skb_trim_rcsum(skb, new_len); 2944 if (!ret && skb_is_gso(skb)) 2945 skb_gso_reset(skb); 2946 } 2947 return ret; 2948 } 2949 2950 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len, 2951 u64, flags) 2952 { 2953 int ret = __bpf_skb_change_tail(skb, new_len, flags); 2954 2955 bpf_compute_data_pointers(skb); 2956 return ret; 2957 } 2958 2959 static const struct bpf_func_proto bpf_skb_change_tail_proto = { 2960 .func = bpf_skb_change_tail, 2961 .gpl_only = false, 2962 .ret_type = RET_INTEGER, 2963 .arg1_type = ARG_PTR_TO_CTX, 2964 .arg2_type = ARG_ANYTHING, 2965 .arg3_type = ARG_ANYTHING, 2966 }; 2967 2968 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len, 2969 u64, flags) 2970 { 2971 int ret = __bpf_skb_change_tail(skb, new_len, flags); 2972 2973 bpf_compute_data_end_sk_skb(skb); 2974 return ret; 2975 } 2976 2977 static const struct bpf_func_proto sk_skb_change_tail_proto = { 2978 .func = sk_skb_change_tail, 2979 .gpl_only = false, 2980 .ret_type = RET_INTEGER, 2981 .arg1_type = ARG_PTR_TO_CTX, 2982 .arg2_type = ARG_ANYTHING, 2983 .arg3_type = ARG_ANYTHING, 2984 }; 2985 2986 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room, 2987 u64 flags) 2988 { 2989 u32 max_len = __bpf_skb_max_len(skb); 2990 u32 new_len = skb->len + head_room; 2991 int ret; 2992 2993 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) || 2994 new_len < skb->len)) 2995 return -EINVAL; 2996 2997 ret = skb_cow(skb, head_room); 2998 if (likely(!ret)) { 2999 /* Idea for this helper is that we currently only 3000 * allow to expand on mac header. This means that 3001 * skb->protocol network header, etc, stay as is. 3002 * Compared to bpf_skb_change_tail(), we're more 3003 * flexible due to not needing to linearize or 3004 * reset GSO. Intention for this helper is to be 3005 * used by an L3 skb that needs to push mac header 3006 * for redirection into L2 device. 3007 */ 3008 __skb_push(skb, head_room); 3009 memset(skb->data, 0, head_room); 3010 skb_reset_mac_header(skb); 3011 } 3012 3013 return ret; 3014 } 3015 3016 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room, 3017 u64, flags) 3018 { 3019 int ret = __bpf_skb_change_head(skb, head_room, flags); 3020 3021 bpf_compute_data_pointers(skb); 3022 return ret; 3023 } 3024 3025 static const struct bpf_func_proto bpf_skb_change_head_proto = { 3026 .func = bpf_skb_change_head, 3027 .gpl_only = false, 3028 .ret_type = RET_INTEGER, 3029 .arg1_type = ARG_PTR_TO_CTX, 3030 .arg2_type = ARG_ANYTHING, 3031 .arg3_type = ARG_ANYTHING, 3032 }; 3033 3034 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room, 3035 u64, flags) 3036 { 3037 int ret = __bpf_skb_change_head(skb, head_room, flags); 3038 3039 bpf_compute_data_end_sk_skb(skb); 3040 return ret; 3041 } 3042 3043 static const struct bpf_func_proto sk_skb_change_head_proto = { 3044 .func = sk_skb_change_head, 3045 .gpl_only = false, 3046 .ret_type = RET_INTEGER, 3047 .arg1_type = ARG_PTR_TO_CTX, 3048 .arg2_type = ARG_ANYTHING, 3049 .arg3_type = ARG_ANYTHING, 3050 }; 3051 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp) 3052 { 3053 return xdp_data_meta_unsupported(xdp) ? 0 : 3054 xdp->data - xdp->data_meta; 3055 } 3056 3057 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset) 3058 { 3059 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); 3060 unsigned long metalen = xdp_get_metalen(xdp); 3061 void *data_start = xdp_frame_end + metalen; 3062 void *data = xdp->data + offset; 3063 3064 if (unlikely(data < data_start || 3065 data > xdp->data_end - ETH_HLEN)) 3066 return -EINVAL; 3067 3068 if (metalen) 3069 memmove(xdp->data_meta + offset, 3070 xdp->data_meta, metalen); 3071 xdp->data_meta += offset; 3072 xdp->data = data; 3073 3074 return 0; 3075 } 3076 3077 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = { 3078 .func = bpf_xdp_adjust_head, 3079 .gpl_only = false, 3080 .ret_type = RET_INTEGER, 3081 .arg1_type = ARG_PTR_TO_CTX, 3082 .arg2_type = ARG_ANYTHING, 3083 }; 3084 3085 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset) 3086 { 3087 void *data_end = xdp->data_end + offset; 3088 3089 /* only shrinking is allowed for now. */ 3090 if (unlikely(offset >= 0)) 3091 return -EINVAL; 3092 3093 if (unlikely(data_end < xdp->data + ETH_HLEN)) 3094 return -EINVAL; 3095 3096 xdp->data_end = data_end; 3097 3098 return 0; 3099 } 3100 3101 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = { 3102 .func = bpf_xdp_adjust_tail, 3103 .gpl_only = false, 3104 .ret_type = RET_INTEGER, 3105 .arg1_type = ARG_PTR_TO_CTX, 3106 .arg2_type = ARG_ANYTHING, 3107 }; 3108 3109 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset) 3110 { 3111 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); 3112 void *meta = xdp->data_meta + offset; 3113 unsigned long metalen = xdp->data - meta; 3114 3115 if (xdp_data_meta_unsupported(xdp)) 3116 return -ENOTSUPP; 3117 if (unlikely(meta < xdp_frame_end || 3118 meta > xdp->data)) 3119 return -EINVAL; 3120 if (unlikely((metalen & (sizeof(__u32) - 1)) || 3121 (metalen > 32))) 3122 return -EACCES; 3123 3124 xdp->data_meta = meta; 3125 3126 return 0; 3127 } 3128 3129 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = { 3130 .func = bpf_xdp_adjust_meta, 3131 .gpl_only = false, 3132 .ret_type = RET_INTEGER, 3133 .arg1_type = ARG_PTR_TO_CTX, 3134 .arg2_type = ARG_ANYTHING, 3135 }; 3136 3137 static int __bpf_tx_xdp(struct net_device *dev, 3138 struct bpf_map *map, 3139 struct xdp_buff *xdp, 3140 u32 index) 3141 { 3142 struct xdp_frame *xdpf; 3143 int err, sent; 3144 3145 if (!dev->netdev_ops->ndo_xdp_xmit) { 3146 return -EOPNOTSUPP; 3147 } 3148 3149 err = xdp_ok_fwd_dev(dev, xdp->data_end - xdp->data); 3150 if (unlikely(err)) 3151 return err; 3152 3153 xdpf = convert_to_xdp_frame(xdp); 3154 if (unlikely(!xdpf)) 3155 return -EOVERFLOW; 3156 3157 sent = dev->netdev_ops->ndo_xdp_xmit(dev, 1, &xdpf, XDP_XMIT_FLUSH); 3158 if (sent <= 0) 3159 return sent; 3160 return 0; 3161 } 3162 3163 static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, 3164 struct bpf_map *map, 3165 struct xdp_buff *xdp, 3166 u32 index) 3167 { 3168 int err; 3169 3170 switch (map->map_type) { 3171 case BPF_MAP_TYPE_DEVMAP: { 3172 struct bpf_dtab_netdev *dst = fwd; 3173 3174 err = dev_map_enqueue(dst, xdp, dev_rx); 3175 if (err) 3176 return err; 3177 __dev_map_insert_ctx(map, index); 3178 break; 3179 } 3180 case BPF_MAP_TYPE_CPUMAP: { 3181 struct bpf_cpu_map_entry *rcpu = fwd; 3182 3183 err = cpu_map_enqueue(rcpu, xdp, dev_rx); 3184 if (err) 3185 return err; 3186 __cpu_map_insert_ctx(map, index); 3187 break; 3188 } 3189 case BPF_MAP_TYPE_XSKMAP: { 3190 struct xdp_sock *xs = fwd; 3191 3192 err = __xsk_map_redirect(map, xdp, xs); 3193 return err; 3194 } 3195 default: 3196 break; 3197 } 3198 return 0; 3199 } 3200 3201 void xdp_do_flush_map(void) 3202 { 3203 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3204 struct bpf_map *map = ri->map_to_flush; 3205 3206 ri->map_to_flush = NULL; 3207 if (map) { 3208 switch (map->map_type) { 3209 case BPF_MAP_TYPE_DEVMAP: 3210 __dev_map_flush(map); 3211 break; 3212 case BPF_MAP_TYPE_CPUMAP: 3213 __cpu_map_flush(map); 3214 break; 3215 case BPF_MAP_TYPE_XSKMAP: 3216 __xsk_map_flush(map); 3217 break; 3218 default: 3219 break; 3220 } 3221 } 3222 } 3223 EXPORT_SYMBOL_GPL(xdp_do_flush_map); 3224 3225 static void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index) 3226 { 3227 switch (map->map_type) { 3228 case BPF_MAP_TYPE_DEVMAP: 3229 return __dev_map_lookup_elem(map, index); 3230 case BPF_MAP_TYPE_CPUMAP: 3231 return __cpu_map_lookup_elem(map, index); 3232 case BPF_MAP_TYPE_XSKMAP: 3233 return __xsk_map_lookup_elem(map, index); 3234 default: 3235 return NULL; 3236 } 3237 } 3238 3239 static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog, 3240 unsigned long aux) 3241 { 3242 return (unsigned long)xdp_prog->aux != aux; 3243 } 3244 3245 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, 3246 struct bpf_prog *xdp_prog) 3247 { 3248 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3249 unsigned long map_owner = ri->map_owner; 3250 struct bpf_map *map = ri->map; 3251 u32 index = ri->ifindex; 3252 void *fwd = NULL; 3253 int err; 3254 3255 ri->ifindex = 0; 3256 ri->map = NULL; 3257 ri->map_owner = 0; 3258 3259 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) { 3260 err = -EFAULT; 3261 map = NULL; 3262 goto err; 3263 } 3264 3265 fwd = __xdp_map_lookup_elem(map, index); 3266 if (!fwd) { 3267 err = -EINVAL; 3268 goto err; 3269 } 3270 if (ri->map_to_flush && ri->map_to_flush != map) 3271 xdp_do_flush_map(); 3272 3273 err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index); 3274 if (unlikely(err)) 3275 goto err; 3276 3277 ri->map_to_flush = map; 3278 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); 3279 return 0; 3280 err: 3281 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); 3282 return err; 3283 } 3284 3285 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, 3286 struct bpf_prog *xdp_prog) 3287 { 3288 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3289 struct net_device *fwd; 3290 u32 index = ri->ifindex; 3291 int err; 3292 3293 if (ri->map) 3294 return xdp_do_redirect_map(dev, xdp, xdp_prog); 3295 3296 fwd = dev_get_by_index_rcu(dev_net(dev), index); 3297 ri->ifindex = 0; 3298 if (unlikely(!fwd)) { 3299 err = -EINVAL; 3300 goto err; 3301 } 3302 3303 err = __bpf_tx_xdp(fwd, NULL, xdp, 0); 3304 if (unlikely(err)) 3305 goto err; 3306 3307 _trace_xdp_redirect(dev, xdp_prog, index); 3308 return 0; 3309 err: 3310 _trace_xdp_redirect_err(dev, xdp_prog, index, err); 3311 return err; 3312 } 3313 EXPORT_SYMBOL_GPL(xdp_do_redirect); 3314 3315 static int xdp_do_generic_redirect_map(struct net_device *dev, 3316 struct sk_buff *skb, 3317 struct xdp_buff *xdp, 3318 struct bpf_prog *xdp_prog) 3319 { 3320 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3321 unsigned long map_owner = ri->map_owner; 3322 struct bpf_map *map = ri->map; 3323 u32 index = ri->ifindex; 3324 void *fwd = NULL; 3325 int err = 0; 3326 3327 ri->ifindex = 0; 3328 ri->map = NULL; 3329 ri->map_owner = 0; 3330 3331 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) { 3332 err = -EFAULT; 3333 map = NULL; 3334 goto err; 3335 } 3336 fwd = __xdp_map_lookup_elem(map, index); 3337 if (unlikely(!fwd)) { 3338 err = -EINVAL; 3339 goto err; 3340 } 3341 3342 if (map->map_type == BPF_MAP_TYPE_DEVMAP) { 3343 struct bpf_dtab_netdev *dst = fwd; 3344 3345 err = dev_map_generic_redirect(dst, skb, xdp_prog); 3346 if (unlikely(err)) 3347 goto err; 3348 } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) { 3349 struct xdp_sock *xs = fwd; 3350 3351 err = xsk_generic_rcv(xs, xdp); 3352 if (err) 3353 goto err; 3354 consume_skb(skb); 3355 } else { 3356 /* TODO: Handle BPF_MAP_TYPE_CPUMAP */ 3357 err = -EBADRQC; 3358 goto err; 3359 } 3360 3361 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); 3362 return 0; 3363 err: 3364 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); 3365 return err; 3366 } 3367 3368 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, 3369 struct xdp_buff *xdp, struct bpf_prog *xdp_prog) 3370 { 3371 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3372 u32 index = ri->ifindex; 3373 struct net_device *fwd; 3374 int err = 0; 3375 3376 if (ri->map) 3377 return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog); 3378 3379 ri->ifindex = 0; 3380 fwd = dev_get_by_index_rcu(dev_net(dev), index); 3381 if (unlikely(!fwd)) { 3382 err = -EINVAL; 3383 goto err; 3384 } 3385 3386 err = xdp_ok_fwd_dev(fwd, skb->len); 3387 if (unlikely(err)) 3388 goto err; 3389 3390 skb->dev = fwd; 3391 _trace_xdp_redirect(dev, xdp_prog, index); 3392 generic_xdp_tx(skb, xdp_prog); 3393 return 0; 3394 err: 3395 _trace_xdp_redirect_err(dev, xdp_prog, index, err); 3396 return err; 3397 } 3398 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect); 3399 3400 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags) 3401 { 3402 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3403 3404 if (unlikely(flags)) 3405 return XDP_ABORTED; 3406 3407 ri->ifindex = ifindex; 3408 ri->flags = flags; 3409 ri->map = NULL; 3410 ri->map_owner = 0; 3411 3412 return XDP_REDIRECT; 3413 } 3414 3415 static const struct bpf_func_proto bpf_xdp_redirect_proto = { 3416 .func = bpf_xdp_redirect, 3417 .gpl_only = false, 3418 .ret_type = RET_INTEGER, 3419 .arg1_type = ARG_ANYTHING, 3420 .arg2_type = ARG_ANYTHING, 3421 }; 3422 3423 BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags, 3424 unsigned long, map_owner) 3425 { 3426 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3427 3428 if (unlikely(flags)) 3429 return XDP_ABORTED; 3430 3431 ri->ifindex = ifindex; 3432 ri->flags = flags; 3433 ri->map = map; 3434 ri->map_owner = map_owner; 3435 3436 return XDP_REDIRECT; 3437 } 3438 3439 /* Note, arg4 is hidden from users and populated by the verifier 3440 * with the right pointer. 3441 */ 3442 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = { 3443 .func = bpf_xdp_redirect_map, 3444 .gpl_only = false, 3445 .ret_type = RET_INTEGER, 3446 .arg1_type = ARG_CONST_MAP_PTR, 3447 .arg2_type = ARG_ANYTHING, 3448 .arg3_type = ARG_ANYTHING, 3449 }; 3450 3451 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb, 3452 unsigned long off, unsigned long len) 3453 { 3454 void *ptr = skb_header_pointer(skb, off, len, dst_buff); 3455 3456 if (unlikely(!ptr)) 3457 return len; 3458 if (ptr != dst_buff) 3459 memcpy(dst_buff, ptr, len); 3460 3461 return 0; 3462 } 3463 3464 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map, 3465 u64, flags, void *, meta, u64, meta_size) 3466 { 3467 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32; 3468 3469 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) 3470 return -EINVAL; 3471 if (unlikely(skb_size > skb->len)) 3472 return -EFAULT; 3473 3474 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size, 3475 bpf_skb_copy); 3476 } 3477 3478 static const struct bpf_func_proto bpf_skb_event_output_proto = { 3479 .func = bpf_skb_event_output, 3480 .gpl_only = true, 3481 .ret_type = RET_INTEGER, 3482 .arg1_type = ARG_PTR_TO_CTX, 3483 .arg2_type = ARG_CONST_MAP_PTR, 3484 .arg3_type = ARG_ANYTHING, 3485 .arg4_type = ARG_PTR_TO_MEM, 3486 .arg5_type = ARG_CONST_SIZE_OR_ZERO, 3487 }; 3488 3489 static unsigned short bpf_tunnel_key_af(u64 flags) 3490 { 3491 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET; 3492 } 3493 3494 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to, 3495 u32, size, u64, flags) 3496 { 3497 const struct ip_tunnel_info *info = skb_tunnel_info(skb); 3498 u8 compat[sizeof(struct bpf_tunnel_key)]; 3499 void *to_orig = to; 3500 int err; 3501 3502 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) { 3503 err = -EINVAL; 3504 goto err_clear; 3505 } 3506 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) { 3507 err = -EPROTO; 3508 goto err_clear; 3509 } 3510 if (unlikely(size != sizeof(struct bpf_tunnel_key))) { 3511 err = -EINVAL; 3512 switch (size) { 3513 case offsetof(struct bpf_tunnel_key, tunnel_label): 3514 case offsetof(struct bpf_tunnel_key, tunnel_ext): 3515 goto set_compat; 3516 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): 3517 /* Fixup deprecated structure layouts here, so we have 3518 * a common path later on. 3519 */ 3520 if (ip_tunnel_info_af(info) != AF_INET) 3521 goto err_clear; 3522 set_compat: 3523 to = (struct bpf_tunnel_key *)compat; 3524 break; 3525 default: 3526 goto err_clear; 3527 } 3528 } 3529 3530 to->tunnel_id = be64_to_cpu(info->key.tun_id); 3531 to->tunnel_tos = info->key.tos; 3532 to->tunnel_ttl = info->key.ttl; 3533 to->tunnel_ext = 0; 3534 3535 if (flags & BPF_F_TUNINFO_IPV6) { 3536 memcpy(to->remote_ipv6, &info->key.u.ipv6.src, 3537 sizeof(to->remote_ipv6)); 3538 to->tunnel_label = be32_to_cpu(info->key.label); 3539 } else { 3540 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src); 3541 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3); 3542 to->tunnel_label = 0; 3543 } 3544 3545 if (unlikely(size != sizeof(struct bpf_tunnel_key))) 3546 memcpy(to_orig, to, size); 3547 3548 return 0; 3549 err_clear: 3550 memset(to_orig, 0, size); 3551 return err; 3552 } 3553 3554 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = { 3555 .func = bpf_skb_get_tunnel_key, 3556 .gpl_only = false, 3557 .ret_type = RET_INTEGER, 3558 .arg1_type = ARG_PTR_TO_CTX, 3559 .arg2_type = ARG_PTR_TO_UNINIT_MEM, 3560 .arg3_type = ARG_CONST_SIZE, 3561 .arg4_type = ARG_ANYTHING, 3562 }; 3563 3564 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size) 3565 { 3566 const struct ip_tunnel_info *info = skb_tunnel_info(skb); 3567 int err; 3568 3569 if (unlikely(!info || 3570 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) { 3571 err = -ENOENT; 3572 goto err_clear; 3573 } 3574 if (unlikely(size < info->options_len)) { 3575 err = -ENOMEM; 3576 goto err_clear; 3577 } 3578 3579 ip_tunnel_info_opts_get(to, info); 3580 if (size > info->options_len) 3581 memset(to + info->options_len, 0, size - info->options_len); 3582 3583 return info->options_len; 3584 err_clear: 3585 memset(to, 0, size); 3586 return err; 3587 } 3588 3589 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = { 3590 .func = bpf_skb_get_tunnel_opt, 3591 .gpl_only = false, 3592 .ret_type = RET_INTEGER, 3593 .arg1_type = ARG_PTR_TO_CTX, 3594 .arg2_type = ARG_PTR_TO_UNINIT_MEM, 3595 .arg3_type = ARG_CONST_SIZE, 3596 }; 3597 3598 static struct metadata_dst __percpu *md_dst; 3599 3600 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb, 3601 const struct bpf_tunnel_key *, from, u32, size, u64, flags) 3602 { 3603 struct metadata_dst *md = this_cpu_ptr(md_dst); 3604 u8 compat[sizeof(struct bpf_tunnel_key)]; 3605 struct ip_tunnel_info *info; 3606 3607 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX | 3608 BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER))) 3609 return -EINVAL; 3610 if (unlikely(size != sizeof(struct bpf_tunnel_key))) { 3611 switch (size) { 3612 case offsetof(struct bpf_tunnel_key, tunnel_label): 3613 case offsetof(struct bpf_tunnel_key, tunnel_ext): 3614 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): 3615 /* Fixup deprecated structure layouts here, so we have 3616 * a common path later on. 3617 */ 3618 memcpy(compat, from, size); 3619 memset(compat + size, 0, sizeof(compat) - size); 3620 from = (const struct bpf_tunnel_key *) compat; 3621 break; 3622 default: 3623 return -EINVAL; 3624 } 3625 } 3626 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) || 3627 from->tunnel_ext)) 3628 return -EINVAL; 3629 3630 skb_dst_drop(skb); 3631 dst_hold((struct dst_entry *) md); 3632 skb_dst_set(skb, (struct dst_entry *) md); 3633 3634 info = &md->u.tun_info; 3635 memset(info, 0, sizeof(*info)); 3636 info->mode = IP_TUNNEL_INFO_TX; 3637 3638 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE; 3639 if (flags & BPF_F_DONT_FRAGMENT) 3640 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT; 3641 if (flags & BPF_F_ZERO_CSUM_TX) 3642 info->key.tun_flags &= ~TUNNEL_CSUM; 3643 if (flags & BPF_F_SEQ_NUMBER) 3644 info->key.tun_flags |= TUNNEL_SEQ; 3645 3646 info->key.tun_id = cpu_to_be64(from->tunnel_id); 3647 info->key.tos = from->tunnel_tos; 3648 info->key.ttl = from->tunnel_ttl; 3649 3650 if (flags & BPF_F_TUNINFO_IPV6) { 3651 info->mode |= IP_TUNNEL_INFO_IPV6; 3652 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6, 3653 sizeof(from->remote_ipv6)); 3654 info->key.label = cpu_to_be32(from->tunnel_label) & 3655 IPV6_FLOWLABEL_MASK; 3656 } else { 3657 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4); 3658 } 3659 3660 return 0; 3661 } 3662 3663 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = { 3664 .func = bpf_skb_set_tunnel_key, 3665 .gpl_only = false, 3666 .ret_type = RET_INTEGER, 3667 .arg1_type = ARG_PTR_TO_CTX, 3668 .arg2_type = ARG_PTR_TO_MEM, 3669 .arg3_type = ARG_CONST_SIZE, 3670 .arg4_type = ARG_ANYTHING, 3671 }; 3672 3673 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb, 3674 const u8 *, from, u32, size) 3675 { 3676 struct ip_tunnel_info *info = skb_tunnel_info(skb); 3677 const struct metadata_dst *md = this_cpu_ptr(md_dst); 3678 3679 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1)))) 3680 return -EINVAL; 3681 if (unlikely(size > IP_TUNNEL_OPTS_MAX)) 3682 return -ENOMEM; 3683 3684 ip_tunnel_info_opts_set(info, from, size); 3685 3686 return 0; 3687 } 3688 3689 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = { 3690 .func = bpf_skb_set_tunnel_opt, 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 }; 3697 3698 static const struct bpf_func_proto * 3699 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which) 3700 { 3701 if (!md_dst) { 3702 struct metadata_dst __percpu *tmp; 3703 3704 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX, 3705 METADATA_IP_TUNNEL, 3706 GFP_KERNEL); 3707 if (!tmp) 3708 return NULL; 3709 if (cmpxchg(&md_dst, NULL, tmp)) 3710 metadata_dst_free_percpu(tmp); 3711 } 3712 3713 switch (which) { 3714 case BPF_FUNC_skb_set_tunnel_key: 3715 return &bpf_skb_set_tunnel_key_proto; 3716 case BPF_FUNC_skb_set_tunnel_opt: 3717 return &bpf_skb_set_tunnel_opt_proto; 3718 default: 3719 return NULL; 3720 } 3721 } 3722 3723 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map, 3724 u32, idx) 3725 { 3726 struct bpf_array *array = container_of(map, struct bpf_array, map); 3727 struct cgroup *cgrp; 3728 struct sock *sk; 3729 3730 sk = skb_to_full_sk(skb); 3731 if (!sk || !sk_fullsock(sk)) 3732 return -ENOENT; 3733 if (unlikely(idx >= array->map.max_entries)) 3734 return -E2BIG; 3735 3736 cgrp = READ_ONCE(array->ptrs[idx]); 3737 if (unlikely(!cgrp)) 3738 return -EAGAIN; 3739 3740 return sk_under_cgroup_hierarchy(sk, cgrp); 3741 } 3742 3743 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = { 3744 .func = bpf_skb_under_cgroup, 3745 .gpl_only = false, 3746 .ret_type = RET_INTEGER, 3747 .arg1_type = ARG_PTR_TO_CTX, 3748 .arg2_type = ARG_CONST_MAP_PTR, 3749 .arg3_type = ARG_ANYTHING, 3750 }; 3751 3752 #ifdef CONFIG_SOCK_CGROUP_DATA 3753 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb) 3754 { 3755 struct sock *sk = skb_to_full_sk(skb); 3756 struct cgroup *cgrp; 3757 3758 if (!sk || !sk_fullsock(sk)) 3759 return 0; 3760 3761 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data); 3762 return cgrp->kn->id.id; 3763 } 3764 3765 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = { 3766 .func = bpf_skb_cgroup_id, 3767 .gpl_only = false, 3768 .ret_type = RET_INTEGER, 3769 .arg1_type = ARG_PTR_TO_CTX, 3770 }; 3771 #endif 3772 3773 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff, 3774 unsigned long off, unsigned long len) 3775 { 3776 memcpy(dst_buff, src_buff + off, len); 3777 return 0; 3778 } 3779 3780 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map, 3781 u64, flags, void *, meta, u64, meta_size) 3782 { 3783 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32; 3784 3785 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) 3786 return -EINVAL; 3787 if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data))) 3788 return -EFAULT; 3789 3790 return bpf_event_output(map, flags, meta, meta_size, xdp->data, 3791 xdp_size, bpf_xdp_copy); 3792 } 3793 3794 static const struct bpf_func_proto bpf_xdp_event_output_proto = { 3795 .func = bpf_xdp_event_output, 3796 .gpl_only = true, 3797 .ret_type = RET_INTEGER, 3798 .arg1_type = ARG_PTR_TO_CTX, 3799 .arg2_type = ARG_CONST_MAP_PTR, 3800 .arg3_type = ARG_ANYTHING, 3801 .arg4_type = ARG_PTR_TO_MEM, 3802 .arg5_type = ARG_CONST_SIZE_OR_ZERO, 3803 }; 3804 3805 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb) 3806 { 3807 return skb->sk ? sock_gen_cookie(skb->sk) : 0; 3808 } 3809 3810 static const struct bpf_func_proto bpf_get_socket_cookie_proto = { 3811 .func = bpf_get_socket_cookie, 3812 .gpl_only = false, 3813 .ret_type = RET_INTEGER, 3814 .arg1_type = ARG_PTR_TO_CTX, 3815 }; 3816 3817 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb) 3818 { 3819 struct sock *sk = sk_to_full_sk(skb->sk); 3820 kuid_t kuid; 3821 3822 if (!sk || !sk_fullsock(sk)) 3823 return overflowuid; 3824 kuid = sock_net_uid(sock_net(sk), sk); 3825 return from_kuid_munged(sock_net(sk)->user_ns, kuid); 3826 } 3827 3828 static const struct bpf_func_proto bpf_get_socket_uid_proto = { 3829 .func = bpf_get_socket_uid, 3830 .gpl_only = false, 3831 .ret_type = RET_INTEGER, 3832 .arg1_type = ARG_PTR_TO_CTX, 3833 }; 3834 3835 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, 3836 int, level, int, optname, char *, optval, int, optlen) 3837 { 3838 struct sock *sk = bpf_sock->sk; 3839 int ret = 0; 3840 int val; 3841 3842 if (!sk_fullsock(sk)) 3843 return -EINVAL; 3844 3845 if (level == SOL_SOCKET) { 3846 if (optlen != sizeof(int)) 3847 return -EINVAL; 3848 val = *((int *)optval); 3849 3850 /* Only some socketops are supported */ 3851 switch (optname) { 3852 case SO_RCVBUF: 3853 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 3854 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF); 3855 break; 3856 case SO_SNDBUF: 3857 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 3858 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF); 3859 break; 3860 case SO_MAX_PACING_RATE: 3861 sk->sk_max_pacing_rate = val; 3862 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 3863 sk->sk_max_pacing_rate); 3864 break; 3865 case SO_PRIORITY: 3866 sk->sk_priority = val; 3867 break; 3868 case SO_RCVLOWAT: 3869 if (val < 0) 3870 val = INT_MAX; 3871 sk->sk_rcvlowat = val ? : 1; 3872 break; 3873 case SO_MARK: 3874 sk->sk_mark = val; 3875 break; 3876 default: 3877 ret = -EINVAL; 3878 } 3879 #ifdef CONFIG_INET 3880 } else if (level == SOL_IP) { 3881 if (optlen != sizeof(int) || sk->sk_family != AF_INET) 3882 return -EINVAL; 3883 3884 val = *((int *)optval); 3885 /* Only some options are supported */ 3886 switch (optname) { 3887 case IP_TOS: 3888 if (val < -1 || val > 0xff) { 3889 ret = -EINVAL; 3890 } else { 3891 struct inet_sock *inet = inet_sk(sk); 3892 3893 if (val == -1) 3894 val = 0; 3895 inet->tos = val; 3896 } 3897 break; 3898 default: 3899 ret = -EINVAL; 3900 } 3901 #if IS_ENABLED(CONFIG_IPV6) 3902 } else if (level == SOL_IPV6) { 3903 if (optlen != sizeof(int) || sk->sk_family != AF_INET6) 3904 return -EINVAL; 3905 3906 val = *((int *)optval); 3907 /* Only some options are supported */ 3908 switch (optname) { 3909 case IPV6_TCLASS: 3910 if (val < -1 || val > 0xff) { 3911 ret = -EINVAL; 3912 } else { 3913 struct ipv6_pinfo *np = inet6_sk(sk); 3914 3915 if (val == -1) 3916 val = 0; 3917 np->tclass = val; 3918 } 3919 break; 3920 default: 3921 ret = -EINVAL; 3922 } 3923 #endif 3924 } else if (level == SOL_TCP && 3925 sk->sk_prot->setsockopt == tcp_setsockopt) { 3926 if (optname == TCP_CONGESTION) { 3927 char name[TCP_CA_NAME_MAX]; 3928 bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN; 3929 3930 strncpy(name, optval, min_t(long, optlen, 3931 TCP_CA_NAME_MAX-1)); 3932 name[TCP_CA_NAME_MAX-1] = 0; 3933 ret = tcp_set_congestion_control(sk, name, false, 3934 reinit); 3935 } else { 3936 struct tcp_sock *tp = tcp_sk(sk); 3937 3938 if (optlen != sizeof(int)) 3939 return -EINVAL; 3940 3941 val = *((int *)optval); 3942 /* Only some options are supported */ 3943 switch (optname) { 3944 case TCP_BPF_IW: 3945 if (val <= 0 || tp->data_segs_out > 0) 3946 ret = -EINVAL; 3947 else 3948 tp->snd_cwnd = val; 3949 break; 3950 case TCP_BPF_SNDCWND_CLAMP: 3951 if (val <= 0) { 3952 ret = -EINVAL; 3953 } else { 3954 tp->snd_cwnd_clamp = val; 3955 tp->snd_ssthresh = val; 3956 } 3957 break; 3958 default: 3959 ret = -EINVAL; 3960 } 3961 } 3962 #endif 3963 } else { 3964 ret = -EINVAL; 3965 } 3966 return ret; 3967 } 3968 3969 static const struct bpf_func_proto bpf_setsockopt_proto = { 3970 .func = bpf_setsockopt, 3971 .gpl_only = false, 3972 .ret_type = RET_INTEGER, 3973 .arg1_type = ARG_PTR_TO_CTX, 3974 .arg2_type = ARG_ANYTHING, 3975 .arg3_type = ARG_ANYTHING, 3976 .arg4_type = ARG_PTR_TO_MEM, 3977 .arg5_type = ARG_CONST_SIZE, 3978 }; 3979 3980 BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock, 3981 int, level, int, optname, char *, optval, int, optlen) 3982 { 3983 struct sock *sk = bpf_sock->sk; 3984 3985 if (!sk_fullsock(sk)) 3986 goto err_clear; 3987 3988 #ifdef CONFIG_INET 3989 if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) { 3990 if (optname == TCP_CONGESTION) { 3991 struct inet_connection_sock *icsk = inet_csk(sk); 3992 3993 if (!icsk->icsk_ca_ops || optlen <= 1) 3994 goto err_clear; 3995 strncpy(optval, icsk->icsk_ca_ops->name, optlen); 3996 optval[optlen - 1] = 0; 3997 } else { 3998 goto err_clear; 3999 } 4000 } else if (level == SOL_IP) { 4001 struct inet_sock *inet = inet_sk(sk); 4002 4003 if (optlen != sizeof(int) || sk->sk_family != AF_INET) 4004 goto err_clear; 4005 4006 /* Only some options are supported */ 4007 switch (optname) { 4008 case IP_TOS: 4009 *((int *)optval) = (int)inet->tos; 4010 break; 4011 default: 4012 goto err_clear; 4013 } 4014 #if IS_ENABLED(CONFIG_IPV6) 4015 } else if (level == SOL_IPV6) { 4016 struct ipv6_pinfo *np = inet6_sk(sk); 4017 4018 if (optlen != sizeof(int) || sk->sk_family != AF_INET6) 4019 goto err_clear; 4020 4021 /* Only some options are supported */ 4022 switch (optname) { 4023 case IPV6_TCLASS: 4024 *((int *)optval) = (int)np->tclass; 4025 break; 4026 default: 4027 goto err_clear; 4028 } 4029 #endif 4030 } else { 4031 goto err_clear; 4032 } 4033 return 0; 4034 #endif 4035 err_clear: 4036 memset(optval, 0, optlen); 4037 return -EINVAL; 4038 } 4039 4040 static const struct bpf_func_proto bpf_getsockopt_proto = { 4041 .func = bpf_getsockopt, 4042 .gpl_only = false, 4043 .ret_type = RET_INTEGER, 4044 .arg1_type = ARG_PTR_TO_CTX, 4045 .arg2_type = ARG_ANYTHING, 4046 .arg3_type = ARG_ANYTHING, 4047 .arg4_type = ARG_PTR_TO_UNINIT_MEM, 4048 .arg5_type = ARG_CONST_SIZE, 4049 }; 4050 4051 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock, 4052 int, argval) 4053 { 4054 struct sock *sk = bpf_sock->sk; 4055 int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS; 4056 4057 if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk)) 4058 return -EINVAL; 4059 4060 if (val) 4061 tcp_sk(sk)->bpf_sock_ops_cb_flags = val; 4062 4063 return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS); 4064 } 4065 4066 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = { 4067 .func = bpf_sock_ops_cb_flags_set, 4068 .gpl_only = false, 4069 .ret_type = RET_INTEGER, 4070 .arg1_type = ARG_PTR_TO_CTX, 4071 .arg2_type = ARG_ANYTHING, 4072 }; 4073 4074 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly; 4075 EXPORT_SYMBOL_GPL(ipv6_bpf_stub); 4076 4077 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr, 4078 int, addr_len) 4079 { 4080 #ifdef CONFIG_INET 4081 struct sock *sk = ctx->sk; 4082 int err; 4083 4084 /* Binding to port can be expensive so it's prohibited in the helper. 4085 * Only binding to IP is supported. 4086 */ 4087 err = -EINVAL; 4088 if (addr->sa_family == AF_INET) { 4089 if (addr_len < sizeof(struct sockaddr_in)) 4090 return err; 4091 if (((struct sockaddr_in *)addr)->sin_port != htons(0)) 4092 return err; 4093 return __inet_bind(sk, addr, addr_len, true, false); 4094 #if IS_ENABLED(CONFIG_IPV6) 4095 } else if (addr->sa_family == AF_INET6) { 4096 if (addr_len < SIN6_LEN_RFC2133) 4097 return err; 4098 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) 4099 return err; 4100 /* ipv6_bpf_stub cannot be NULL, since it's called from 4101 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded 4102 */ 4103 return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, true, false); 4104 #endif /* CONFIG_IPV6 */ 4105 } 4106 #endif /* CONFIG_INET */ 4107 4108 return -EAFNOSUPPORT; 4109 } 4110 4111 static const struct bpf_func_proto bpf_bind_proto = { 4112 .func = bpf_bind, 4113 .gpl_only = false, 4114 .ret_type = RET_INTEGER, 4115 .arg1_type = ARG_PTR_TO_CTX, 4116 .arg2_type = ARG_PTR_TO_MEM, 4117 .arg3_type = ARG_CONST_SIZE, 4118 }; 4119 4120 #ifdef CONFIG_XFRM 4121 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index, 4122 struct bpf_xfrm_state *, to, u32, size, u64, flags) 4123 { 4124 const struct sec_path *sp = skb_sec_path(skb); 4125 const struct xfrm_state *x; 4126 4127 if (!sp || unlikely(index >= sp->len || flags)) 4128 goto err_clear; 4129 4130 x = sp->xvec[index]; 4131 4132 if (unlikely(size != sizeof(struct bpf_xfrm_state))) 4133 goto err_clear; 4134 4135 to->reqid = x->props.reqid; 4136 to->spi = x->id.spi; 4137 to->family = x->props.family; 4138 to->ext = 0; 4139 4140 if (to->family == AF_INET6) { 4141 memcpy(to->remote_ipv6, x->props.saddr.a6, 4142 sizeof(to->remote_ipv6)); 4143 } else { 4144 to->remote_ipv4 = x->props.saddr.a4; 4145 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3); 4146 } 4147 4148 return 0; 4149 err_clear: 4150 memset(to, 0, size); 4151 return -EINVAL; 4152 } 4153 4154 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = { 4155 .func = bpf_skb_get_xfrm_state, 4156 .gpl_only = false, 4157 .ret_type = RET_INTEGER, 4158 .arg1_type = ARG_PTR_TO_CTX, 4159 .arg2_type = ARG_ANYTHING, 4160 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 4161 .arg4_type = ARG_CONST_SIZE, 4162 .arg5_type = ARG_ANYTHING, 4163 }; 4164 #endif 4165 4166 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6) 4167 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, 4168 const struct neighbour *neigh, 4169 const struct net_device *dev) 4170 { 4171 memcpy(params->dmac, neigh->ha, ETH_ALEN); 4172 memcpy(params->smac, dev->dev_addr, ETH_ALEN); 4173 params->h_vlan_TCI = 0; 4174 params->h_vlan_proto = 0; 4175 params->ifindex = dev->ifindex; 4176 4177 return 0; 4178 } 4179 #endif 4180 4181 #if IS_ENABLED(CONFIG_INET) 4182 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, 4183 u32 flags, bool check_mtu) 4184 { 4185 struct in_device *in_dev; 4186 struct neighbour *neigh; 4187 struct net_device *dev; 4188 struct fib_result res; 4189 struct fib_nh *nh; 4190 struct flowi4 fl4; 4191 int err; 4192 u32 mtu; 4193 4194 dev = dev_get_by_index_rcu(net, params->ifindex); 4195 if (unlikely(!dev)) 4196 return -ENODEV; 4197 4198 /* verify forwarding is enabled on this interface */ 4199 in_dev = __in_dev_get_rcu(dev); 4200 if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev))) 4201 return BPF_FIB_LKUP_RET_FWD_DISABLED; 4202 4203 if (flags & BPF_FIB_LOOKUP_OUTPUT) { 4204 fl4.flowi4_iif = 1; 4205 fl4.flowi4_oif = params->ifindex; 4206 } else { 4207 fl4.flowi4_iif = params->ifindex; 4208 fl4.flowi4_oif = 0; 4209 } 4210 fl4.flowi4_tos = params->tos & IPTOS_RT_MASK; 4211 fl4.flowi4_scope = RT_SCOPE_UNIVERSE; 4212 fl4.flowi4_flags = 0; 4213 4214 fl4.flowi4_proto = params->l4_protocol; 4215 fl4.daddr = params->ipv4_dst; 4216 fl4.saddr = params->ipv4_src; 4217 fl4.fl4_sport = params->sport; 4218 fl4.fl4_dport = params->dport; 4219 4220 if (flags & BPF_FIB_LOOKUP_DIRECT) { 4221 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN; 4222 struct fib_table *tb; 4223 4224 tb = fib_get_table(net, tbid); 4225 if (unlikely(!tb)) 4226 return BPF_FIB_LKUP_RET_NOT_FWDED; 4227 4228 err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); 4229 } else { 4230 fl4.flowi4_mark = 0; 4231 fl4.flowi4_secid = 0; 4232 fl4.flowi4_tun_key.tun_id = 0; 4233 fl4.flowi4_uid = sock_net_uid(net, NULL); 4234 4235 err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF); 4236 } 4237 4238 if (err) { 4239 /* map fib lookup errors to RTN_ type */ 4240 if (err == -EINVAL) 4241 return BPF_FIB_LKUP_RET_BLACKHOLE; 4242 if (err == -EHOSTUNREACH) 4243 return BPF_FIB_LKUP_RET_UNREACHABLE; 4244 if (err == -EACCES) 4245 return BPF_FIB_LKUP_RET_PROHIBIT; 4246 4247 return BPF_FIB_LKUP_RET_NOT_FWDED; 4248 } 4249 4250 if (res.type != RTN_UNICAST) 4251 return BPF_FIB_LKUP_RET_NOT_FWDED; 4252 4253 if (res.fi->fib_nhs > 1) 4254 fib_select_path(net, &res, &fl4, NULL); 4255 4256 if (check_mtu) { 4257 mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst); 4258 if (params->tot_len > mtu) 4259 return BPF_FIB_LKUP_RET_FRAG_NEEDED; 4260 } 4261 4262 nh = &res.fi->fib_nh[res.nh_sel]; 4263 4264 /* do not handle lwt encaps right now */ 4265 if (nh->nh_lwtstate) 4266 return BPF_FIB_LKUP_RET_UNSUPP_LWT; 4267 4268 dev = nh->nh_dev; 4269 if (nh->nh_gw) 4270 params->ipv4_dst = nh->nh_gw; 4271 4272 params->rt_metric = res.fi->fib_priority; 4273 4274 /* xdp and cls_bpf programs are run in RCU-bh so 4275 * rcu_read_lock_bh is not needed here 4276 */ 4277 neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)params->ipv4_dst); 4278 if (!neigh) 4279 return BPF_FIB_LKUP_RET_NO_NEIGH; 4280 4281 return bpf_fib_set_fwd_params(params, neigh, dev); 4282 } 4283 #endif 4284 4285 #if IS_ENABLED(CONFIG_IPV6) 4286 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, 4287 u32 flags, bool check_mtu) 4288 { 4289 struct in6_addr *src = (struct in6_addr *) params->ipv6_src; 4290 struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst; 4291 struct neighbour *neigh; 4292 struct net_device *dev; 4293 struct inet6_dev *idev; 4294 struct fib6_info *f6i; 4295 struct flowi6 fl6; 4296 int strict = 0; 4297 int oif; 4298 u32 mtu; 4299 4300 /* link local addresses are never forwarded */ 4301 if (rt6_need_strict(dst) || rt6_need_strict(src)) 4302 return BPF_FIB_LKUP_RET_NOT_FWDED; 4303 4304 dev = dev_get_by_index_rcu(net, params->ifindex); 4305 if (unlikely(!dev)) 4306 return -ENODEV; 4307 4308 idev = __in6_dev_get_safely(dev); 4309 if (unlikely(!idev || !net->ipv6.devconf_all->forwarding)) 4310 return BPF_FIB_LKUP_RET_FWD_DISABLED; 4311 4312 if (flags & BPF_FIB_LOOKUP_OUTPUT) { 4313 fl6.flowi6_iif = 1; 4314 oif = fl6.flowi6_oif = params->ifindex; 4315 } else { 4316 oif = fl6.flowi6_iif = params->ifindex; 4317 fl6.flowi6_oif = 0; 4318 strict = RT6_LOOKUP_F_HAS_SADDR; 4319 } 4320 fl6.flowlabel = params->flowinfo; 4321 fl6.flowi6_scope = 0; 4322 fl6.flowi6_flags = 0; 4323 fl6.mp_hash = 0; 4324 4325 fl6.flowi6_proto = params->l4_protocol; 4326 fl6.daddr = *dst; 4327 fl6.saddr = *src; 4328 fl6.fl6_sport = params->sport; 4329 fl6.fl6_dport = params->dport; 4330 4331 if (flags & BPF_FIB_LOOKUP_DIRECT) { 4332 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN; 4333 struct fib6_table *tb; 4334 4335 tb = ipv6_stub->fib6_get_table(net, tbid); 4336 if (unlikely(!tb)) 4337 return BPF_FIB_LKUP_RET_NOT_FWDED; 4338 4339 f6i = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, strict); 4340 } else { 4341 fl6.flowi6_mark = 0; 4342 fl6.flowi6_secid = 0; 4343 fl6.flowi6_tun_key.tun_id = 0; 4344 fl6.flowi6_uid = sock_net_uid(net, NULL); 4345 4346 f6i = ipv6_stub->fib6_lookup(net, oif, &fl6, strict); 4347 } 4348 4349 if (unlikely(IS_ERR_OR_NULL(f6i) || f6i == net->ipv6.fib6_null_entry)) 4350 return BPF_FIB_LKUP_RET_NOT_FWDED; 4351 4352 if (unlikely(f6i->fib6_flags & RTF_REJECT)) { 4353 switch (f6i->fib6_type) { 4354 case RTN_BLACKHOLE: 4355 return BPF_FIB_LKUP_RET_BLACKHOLE; 4356 case RTN_UNREACHABLE: 4357 return BPF_FIB_LKUP_RET_UNREACHABLE; 4358 case RTN_PROHIBIT: 4359 return BPF_FIB_LKUP_RET_PROHIBIT; 4360 default: 4361 return BPF_FIB_LKUP_RET_NOT_FWDED; 4362 } 4363 } 4364 4365 if (f6i->fib6_type != RTN_UNICAST) 4366 return BPF_FIB_LKUP_RET_NOT_FWDED; 4367 4368 if (f6i->fib6_nsiblings && fl6.flowi6_oif == 0) 4369 f6i = ipv6_stub->fib6_multipath_select(net, f6i, &fl6, 4370 fl6.flowi6_oif, NULL, 4371 strict); 4372 4373 if (check_mtu) { 4374 mtu = ipv6_stub->ip6_mtu_from_fib6(f6i, dst, src); 4375 if (params->tot_len > mtu) 4376 return BPF_FIB_LKUP_RET_FRAG_NEEDED; 4377 } 4378 4379 if (f6i->fib6_nh.nh_lwtstate) 4380 return BPF_FIB_LKUP_RET_UNSUPP_LWT; 4381 4382 if (f6i->fib6_flags & RTF_GATEWAY) 4383 *dst = f6i->fib6_nh.nh_gw; 4384 4385 dev = f6i->fib6_nh.nh_dev; 4386 params->rt_metric = f6i->fib6_metric; 4387 4388 /* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is 4389 * not needed here. Can not use __ipv6_neigh_lookup_noref here 4390 * because we need to get nd_tbl via the stub 4391 */ 4392 neigh = ___neigh_lookup_noref(ipv6_stub->nd_tbl, neigh_key_eq128, 4393 ndisc_hashfn, dst, dev); 4394 if (!neigh) 4395 return BPF_FIB_LKUP_RET_NO_NEIGH; 4396 4397 return bpf_fib_set_fwd_params(params, neigh, dev); 4398 } 4399 #endif 4400 4401 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx, 4402 struct bpf_fib_lookup *, params, int, plen, u32, flags) 4403 { 4404 if (plen < sizeof(*params)) 4405 return -EINVAL; 4406 4407 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT)) 4408 return -EINVAL; 4409 4410 switch (params->family) { 4411 #if IS_ENABLED(CONFIG_INET) 4412 case AF_INET: 4413 return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params, 4414 flags, true); 4415 #endif 4416 #if IS_ENABLED(CONFIG_IPV6) 4417 case AF_INET6: 4418 return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params, 4419 flags, true); 4420 #endif 4421 } 4422 return -EAFNOSUPPORT; 4423 } 4424 4425 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = { 4426 .func = bpf_xdp_fib_lookup, 4427 .gpl_only = true, 4428 .ret_type = RET_INTEGER, 4429 .arg1_type = ARG_PTR_TO_CTX, 4430 .arg2_type = ARG_PTR_TO_MEM, 4431 .arg3_type = ARG_CONST_SIZE, 4432 .arg4_type = ARG_ANYTHING, 4433 }; 4434 4435 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb, 4436 struct bpf_fib_lookup *, params, int, plen, u32, flags) 4437 { 4438 struct net *net = dev_net(skb->dev); 4439 int rc = -EAFNOSUPPORT; 4440 4441 if (plen < sizeof(*params)) 4442 return -EINVAL; 4443 4444 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT)) 4445 return -EINVAL; 4446 4447 switch (params->family) { 4448 #if IS_ENABLED(CONFIG_INET) 4449 case AF_INET: 4450 rc = bpf_ipv4_fib_lookup(net, params, flags, false); 4451 break; 4452 #endif 4453 #if IS_ENABLED(CONFIG_IPV6) 4454 case AF_INET6: 4455 rc = bpf_ipv6_fib_lookup(net, params, flags, false); 4456 break; 4457 #endif 4458 } 4459 4460 if (!rc) { 4461 struct net_device *dev; 4462 4463 dev = dev_get_by_index_rcu(net, params->ifindex); 4464 if (!is_skb_forwardable(dev, skb)) 4465 rc = BPF_FIB_LKUP_RET_FRAG_NEEDED; 4466 } 4467 4468 return rc; 4469 } 4470 4471 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = { 4472 .func = bpf_skb_fib_lookup, 4473 .gpl_only = true, 4474 .ret_type = RET_INTEGER, 4475 .arg1_type = ARG_PTR_TO_CTX, 4476 .arg2_type = ARG_PTR_TO_MEM, 4477 .arg3_type = ARG_CONST_SIZE, 4478 .arg4_type = ARG_ANYTHING, 4479 }; 4480 4481 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4482 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len) 4483 { 4484 int err; 4485 struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr; 4486 4487 if (!seg6_validate_srh(srh, len)) 4488 return -EINVAL; 4489 4490 switch (type) { 4491 case BPF_LWT_ENCAP_SEG6_INLINE: 4492 if (skb->protocol != htons(ETH_P_IPV6)) 4493 return -EBADMSG; 4494 4495 err = seg6_do_srh_inline(skb, srh); 4496 break; 4497 case BPF_LWT_ENCAP_SEG6: 4498 skb_reset_inner_headers(skb); 4499 skb->encapsulation = 1; 4500 err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6); 4501 break; 4502 default: 4503 return -EINVAL; 4504 } 4505 4506 bpf_compute_data_pointers(skb); 4507 if (err) 4508 return err; 4509 4510 ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 4511 skb_set_transport_header(skb, sizeof(struct ipv6hdr)); 4512 4513 return seg6_lookup_nexthop(skb, NULL, 0); 4514 } 4515 #endif /* CONFIG_IPV6_SEG6_BPF */ 4516 4517 BPF_CALL_4(bpf_lwt_push_encap, struct sk_buff *, skb, u32, type, void *, hdr, 4518 u32, len) 4519 { 4520 switch (type) { 4521 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4522 case BPF_LWT_ENCAP_SEG6: 4523 case BPF_LWT_ENCAP_SEG6_INLINE: 4524 return bpf_push_seg6_encap(skb, type, hdr, len); 4525 #endif 4526 default: 4527 return -EINVAL; 4528 } 4529 } 4530 4531 static const struct bpf_func_proto bpf_lwt_push_encap_proto = { 4532 .func = bpf_lwt_push_encap, 4533 .gpl_only = false, 4534 .ret_type = RET_INTEGER, 4535 .arg1_type = ARG_PTR_TO_CTX, 4536 .arg2_type = ARG_ANYTHING, 4537 .arg3_type = ARG_PTR_TO_MEM, 4538 .arg4_type = ARG_CONST_SIZE 4539 }; 4540 4541 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4542 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset, 4543 const void *, from, u32, len) 4544 { 4545 struct seg6_bpf_srh_state *srh_state = 4546 this_cpu_ptr(&seg6_bpf_srh_states); 4547 void *srh_tlvs, *srh_end, *ptr; 4548 struct ipv6_sr_hdr *srh; 4549 int srhoff = 0; 4550 4551 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4552 return -EINVAL; 4553 4554 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4555 srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4)); 4556 srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen); 4557 4558 ptr = skb->data + offset; 4559 if (ptr >= srh_tlvs && ptr + len <= srh_end) 4560 srh_state->valid = 0; 4561 else if (ptr < (void *)&srh->flags || 4562 ptr + len > (void *)&srh->segments) 4563 return -EFAULT; 4564 4565 if (unlikely(bpf_try_make_writable(skb, offset + len))) 4566 return -EFAULT; 4567 4568 memcpy(skb->data + offset, from, len); 4569 return 0; 4570 } 4571 4572 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = { 4573 .func = bpf_lwt_seg6_store_bytes, 4574 .gpl_only = false, 4575 .ret_type = RET_INTEGER, 4576 .arg1_type = ARG_PTR_TO_CTX, 4577 .arg2_type = ARG_ANYTHING, 4578 .arg3_type = ARG_PTR_TO_MEM, 4579 .arg4_type = ARG_CONST_SIZE 4580 }; 4581 4582 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb, 4583 u32, action, void *, param, u32, param_len) 4584 { 4585 struct seg6_bpf_srh_state *srh_state = 4586 this_cpu_ptr(&seg6_bpf_srh_states); 4587 struct ipv6_sr_hdr *srh; 4588 int srhoff = 0; 4589 int err; 4590 4591 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4592 return -EINVAL; 4593 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4594 4595 if (!srh_state->valid) { 4596 if (unlikely((srh_state->hdrlen & 7) != 0)) 4597 return -EBADMSG; 4598 4599 srh->hdrlen = (u8)(srh_state->hdrlen >> 3); 4600 if (unlikely(!seg6_validate_srh(srh, (srh->hdrlen + 1) << 3))) 4601 return -EBADMSG; 4602 4603 srh_state->valid = 1; 4604 } 4605 4606 switch (action) { 4607 case SEG6_LOCAL_ACTION_END_X: 4608 if (param_len != sizeof(struct in6_addr)) 4609 return -EINVAL; 4610 return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0); 4611 case SEG6_LOCAL_ACTION_END_T: 4612 if (param_len != sizeof(int)) 4613 return -EINVAL; 4614 return seg6_lookup_nexthop(skb, NULL, *(int *)param); 4615 case SEG6_LOCAL_ACTION_END_B6: 4616 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE, 4617 param, param_len); 4618 if (!err) 4619 srh_state->hdrlen = 4620 ((struct ipv6_sr_hdr *)param)->hdrlen << 3; 4621 return err; 4622 case SEG6_LOCAL_ACTION_END_B6_ENCAP: 4623 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6, 4624 param, param_len); 4625 if (!err) 4626 srh_state->hdrlen = 4627 ((struct ipv6_sr_hdr *)param)->hdrlen << 3; 4628 return err; 4629 default: 4630 return -EINVAL; 4631 } 4632 } 4633 4634 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = { 4635 .func = bpf_lwt_seg6_action, 4636 .gpl_only = false, 4637 .ret_type = RET_INTEGER, 4638 .arg1_type = ARG_PTR_TO_CTX, 4639 .arg2_type = ARG_ANYTHING, 4640 .arg3_type = ARG_PTR_TO_MEM, 4641 .arg4_type = ARG_CONST_SIZE 4642 }; 4643 4644 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset, 4645 s32, len) 4646 { 4647 struct seg6_bpf_srh_state *srh_state = 4648 this_cpu_ptr(&seg6_bpf_srh_states); 4649 void *srh_end, *srh_tlvs, *ptr; 4650 struct ipv6_sr_hdr *srh; 4651 struct ipv6hdr *hdr; 4652 int srhoff = 0; 4653 int ret; 4654 4655 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4656 return -EINVAL; 4657 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4658 4659 srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) + 4660 ((srh->first_segment + 1) << 4)); 4661 srh_end = (void *)((unsigned char *)srh + sizeof(*srh) + 4662 srh_state->hdrlen); 4663 ptr = skb->data + offset; 4664 4665 if (unlikely(ptr < srh_tlvs || ptr > srh_end)) 4666 return -EFAULT; 4667 if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end)) 4668 return -EFAULT; 4669 4670 if (len > 0) { 4671 ret = skb_cow_head(skb, len); 4672 if (unlikely(ret < 0)) 4673 return ret; 4674 4675 ret = bpf_skb_net_hdr_push(skb, offset, len); 4676 } else { 4677 ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len); 4678 } 4679 4680 bpf_compute_data_pointers(skb); 4681 if (unlikely(ret < 0)) 4682 return ret; 4683 4684 hdr = (struct ipv6hdr *)skb->data; 4685 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 4686 4687 srh_state->hdrlen += len; 4688 srh_state->valid = 0; 4689 return 0; 4690 } 4691 4692 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = { 4693 .func = bpf_lwt_seg6_adjust_srh, 4694 .gpl_only = false, 4695 .ret_type = RET_INTEGER, 4696 .arg1_type = ARG_PTR_TO_CTX, 4697 .arg2_type = ARG_ANYTHING, 4698 .arg3_type = ARG_ANYTHING, 4699 }; 4700 #endif /* CONFIG_IPV6_SEG6_BPF */ 4701 4702 bool bpf_helper_changes_pkt_data(void *func) 4703 { 4704 if (func == bpf_skb_vlan_push || 4705 func == bpf_skb_vlan_pop || 4706 func == bpf_skb_store_bytes || 4707 func == bpf_skb_change_proto || 4708 func == bpf_skb_change_head || 4709 func == sk_skb_change_head || 4710 func == bpf_skb_change_tail || 4711 func == sk_skb_change_tail || 4712 func == bpf_skb_adjust_room || 4713 func == bpf_skb_pull_data || 4714 func == sk_skb_pull_data || 4715 func == bpf_clone_redirect || 4716 func == bpf_l3_csum_replace || 4717 func == bpf_l4_csum_replace || 4718 func == bpf_xdp_adjust_head || 4719 func == bpf_xdp_adjust_meta || 4720 func == bpf_msg_pull_data || 4721 func == bpf_xdp_adjust_tail || 4722 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4723 func == bpf_lwt_seg6_store_bytes || 4724 func == bpf_lwt_seg6_adjust_srh || 4725 func == bpf_lwt_seg6_action || 4726 #endif 4727 func == bpf_lwt_push_encap) 4728 return true; 4729 4730 return false; 4731 } 4732 4733 static const struct bpf_func_proto * 4734 bpf_base_func_proto(enum bpf_func_id func_id) 4735 { 4736 switch (func_id) { 4737 case BPF_FUNC_map_lookup_elem: 4738 return &bpf_map_lookup_elem_proto; 4739 case BPF_FUNC_map_update_elem: 4740 return &bpf_map_update_elem_proto; 4741 case BPF_FUNC_map_delete_elem: 4742 return &bpf_map_delete_elem_proto; 4743 case BPF_FUNC_get_prandom_u32: 4744 return &bpf_get_prandom_u32_proto; 4745 case BPF_FUNC_get_smp_processor_id: 4746 return &bpf_get_raw_smp_processor_id_proto; 4747 case BPF_FUNC_get_numa_node_id: 4748 return &bpf_get_numa_node_id_proto; 4749 case BPF_FUNC_tail_call: 4750 return &bpf_tail_call_proto; 4751 case BPF_FUNC_ktime_get_ns: 4752 return &bpf_ktime_get_ns_proto; 4753 case BPF_FUNC_trace_printk: 4754 if (capable(CAP_SYS_ADMIN)) 4755 return bpf_get_trace_printk_proto(); 4756 default: 4757 return NULL; 4758 } 4759 } 4760 4761 static const struct bpf_func_proto * 4762 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4763 { 4764 switch (func_id) { 4765 /* inet and inet6 sockets are created in a process 4766 * context so there is always a valid uid/gid 4767 */ 4768 case BPF_FUNC_get_current_uid_gid: 4769 return &bpf_get_current_uid_gid_proto; 4770 default: 4771 return bpf_base_func_proto(func_id); 4772 } 4773 } 4774 4775 static const struct bpf_func_proto * 4776 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4777 { 4778 switch (func_id) { 4779 /* inet and inet6 sockets are created in a process 4780 * context so there is always a valid uid/gid 4781 */ 4782 case BPF_FUNC_get_current_uid_gid: 4783 return &bpf_get_current_uid_gid_proto; 4784 case BPF_FUNC_bind: 4785 switch (prog->expected_attach_type) { 4786 case BPF_CGROUP_INET4_CONNECT: 4787 case BPF_CGROUP_INET6_CONNECT: 4788 return &bpf_bind_proto; 4789 default: 4790 return NULL; 4791 } 4792 default: 4793 return bpf_base_func_proto(func_id); 4794 } 4795 } 4796 4797 static const struct bpf_func_proto * 4798 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4799 { 4800 switch (func_id) { 4801 case BPF_FUNC_skb_load_bytes: 4802 return &bpf_skb_load_bytes_proto; 4803 case BPF_FUNC_skb_load_bytes_relative: 4804 return &bpf_skb_load_bytes_relative_proto; 4805 case BPF_FUNC_get_socket_cookie: 4806 return &bpf_get_socket_cookie_proto; 4807 case BPF_FUNC_get_socket_uid: 4808 return &bpf_get_socket_uid_proto; 4809 default: 4810 return bpf_base_func_proto(func_id); 4811 } 4812 } 4813 4814 static const struct bpf_func_proto * 4815 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4816 { 4817 switch (func_id) { 4818 case BPF_FUNC_skb_store_bytes: 4819 return &bpf_skb_store_bytes_proto; 4820 case BPF_FUNC_skb_load_bytes: 4821 return &bpf_skb_load_bytes_proto; 4822 case BPF_FUNC_skb_load_bytes_relative: 4823 return &bpf_skb_load_bytes_relative_proto; 4824 case BPF_FUNC_skb_pull_data: 4825 return &bpf_skb_pull_data_proto; 4826 case BPF_FUNC_csum_diff: 4827 return &bpf_csum_diff_proto; 4828 case BPF_FUNC_csum_update: 4829 return &bpf_csum_update_proto; 4830 case BPF_FUNC_l3_csum_replace: 4831 return &bpf_l3_csum_replace_proto; 4832 case BPF_FUNC_l4_csum_replace: 4833 return &bpf_l4_csum_replace_proto; 4834 case BPF_FUNC_clone_redirect: 4835 return &bpf_clone_redirect_proto; 4836 case BPF_FUNC_get_cgroup_classid: 4837 return &bpf_get_cgroup_classid_proto; 4838 case BPF_FUNC_skb_vlan_push: 4839 return &bpf_skb_vlan_push_proto; 4840 case BPF_FUNC_skb_vlan_pop: 4841 return &bpf_skb_vlan_pop_proto; 4842 case BPF_FUNC_skb_change_proto: 4843 return &bpf_skb_change_proto_proto; 4844 case BPF_FUNC_skb_change_type: 4845 return &bpf_skb_change_type_proto; 4846 case BPF_FUNC_skb_adjust_room: 4847 return &bpf_skb_adjust_room_proto; 4848 case BPF_FUNC_skb_change_tail: 4849 return &bpf_skb_change_tail_proto; 4850 case BPF_FUNC_skb_get_tunnel_key: 4851 return &bpf_skb_get_tunnel_key_proto; 4852 case BPF_FUNC_skb_set_tunnel_key: 4853 return bpf_get_skb_set_tunnel_proto(func_id); 4854 case BPF_FUNC_skb_get_tunnel_opt: 4855 return &bpf_skb_get_tunnel_opt_proto; 4856 case BPF_FUNC_skb_set_tunnel_opt: 4857 return bpf_get_skb_set_tunnel_proto(func_id); 4858 case BPF_FUNC_redirect: 4859 return &bpf_redirect_proto; 4860 case BPF_FUNC_get_route_realm: 4861 return &bpf_get_route_realm_proto; 4862 case BPF_FUNC_get_hash_recalc: 4863 return &bpf_get_hash_recalc_proto; 4864 case BPF_FUNC_set_hash_invalid: 4865 return &bpf_set_hash_invalid_proto; 4866 case BPF_FUNC_set_hash: 4867 return &bpf_set_hash_proto; 4868 case BPF_FUNC_perf_event_output: 4869 return &bpf_skb_event_output_proto; 4870 case BPF_FUNC_get_smp_processor_id: 4871 return &bpf_get_smp_processor_id_proto; 4872 case BPF_FUNC_skb_under_cgroup: 4873 return &bpf_skb_under_cgroup_proto; 4874 case BPF_FUNC_get_socket_cookie: 4875 return &bpf_get_socket_cookie_proto; 4876 case BPF_FUNC_get_socket_uid: 4877 return &bpf_get_socket_uid_proto; 4878 case BPF_FUNC_fib_lookup: 4879 return &bpf_skb_fib_lookup_proto; 4880 #ifdef CONFIG_XFRM 4881 case BPF_FUNC_skb_get_xfrm_state: 4882 return &bpf_skb_get_xfrm_state_proto; 4883 #endif 4884 #ifdef CONFIG_SOCK_CGROUP_DATA 4885 case BPF_FUNC_skb_cgroup_id: 4886 return &bpf_skb_cgroup_id_proto; 4887 #endif 4888 default: 4889 return bpf_base_func_proto(func_id); 4890 } 4891 } 4892 4893 static const struct bpf_func_proto * 4894 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4895 { 4896 switch (func_id) { 4897 case BPF_FUNC_perf_event_output: 4898 return &bpf_xdp_event_output_proto; 4899 case BPF_FUNC_get_smp_processor_id: 4900 return &bpf_get_smp_processor_id_proto; 4901 case BPF_FUNC_csum_diff: 4902 return &bpf_csum_diff_proto; 4903 case BPF_FUNC_xdp_adjust_head: 4904 return &bpf_xdp_adjust_head_proto; 4905 case BPF_FUNC_xdp_adjust_meta: 4906 return &bpf_xdp_adjust_meta_proto; 4907 case BPF_FUNC_redirect: 4908 return &bpf_xdp_redirect_proto; 4909 case BPF_FUNC_redirect_map: 4910 return &bpf_xdp_redirect_map_proto; 4911 case BPF_FUNC_xdp_adjust_tail: 4912 return &bpf_xdp_adjust_tail_proto; 4913 case BPF_FUNC_fib_lookup: 4914 return &bpf_xdp_fib_lookup_proto; 4915 default: 4916 return bpf_base_func_proto(func_id); 4917 } 4918 } 4919 4920 static const struct bpf_func_proto * 4921 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4922 { 4923 switch (func_id) { 4924 case BPF_FUNC_setsockopt: 4925 return &bpf_setsockopt_proto; 4926 case BPF_FUNC_getsockopt: 4927 return &bpf_getsockopt_proto; 4928 case BPF_FUNC_sock_ops_cb_flags_set: 4929 return &bpf_sock_ops_cb_flags_set_proto; 4930 case BPF_FUNC_sock_map_update: 4931 return &bpf_sock_map_update_proto; 4932 case BPF_FUNC_sock_hash_update: 4933 return &bpf_sock_hash_update_proto; 4934 default: 4935 return bpf_base_func_proto(func_id); 4936 } 4937 } 4938 4939 static const struct bpf_func_proto * 4940 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4941 { 4942 switch (func_id) { 4943 case BPF_FUNC_msg_redirect_map: 4944 return &bpf_msg_redirect_map_proto; 4945 case BPF_FUNC_msg_redirect_hash: 4946 return &bpf_msg_redirect_hash_proto; 4947 case BPF_FUNC_msg_apply_bytes: 4948 return &bpf_msg_apply_bytes_proto; 4949 case BPF_FUNC_msg_cork_bytes: 4950 return &bpf_msg_cork_bytes_proto; 4951 case BPF_FUNC_msg_pull_data: 4952 return &bpf_msg_pull_data_proto; 4953 default: 4954 return bpf_base_func_proto(func_id); 4955 } 4956 } 4957 4958 static const struct bpf_func_proto * 4959 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4960 { 4961 switch (func_id) { 4962 case BPF_FUNC_skb_store_bytes: 4963 return &bpf_skb_store_bytes_proto; 4964 case BPF_FUNC_skb_load_bytes: 4965 return &bpf_skb_load_bytes_proto; 4966 case BPF_FUNC_skb_pull_data: 4967 return &sk_skb_pull_data_proto; 4968 case BPF_FUNC_skb_change_tail: 4969 return &sk_skb_change_tail_proto; 4970 case BPF_FUNC_skb_change_head: 4971 return &sk_skb_change_head_proto; 4972 case BPF_FUNC_get_socket_cookie: 4973 return &bpf_get_socket_cookie_proto; 4974 case BPF_FUNC_get_socket_uid: 4975 return &bpf_get_socket_uid_proto; 4976 case BPF_FUNC_sk_redirect_map: 4977 return &bpf_sk_redirect_map_proto; 4978 case BPF_FUNC_sk_redirect_hash: 4979 return &bpf_sk_redirect_hash_proto; 4980 default: 4981 return bpf_base_func_proto(func_id); 4982 } 4983 } 4984 4985 static const struct bpf_func_proto * 4986 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4987 { 4988 switch (func_id) { 4989 case BPF_FUNC_skb_load_bytes: 4990 return &bpf_skb_load_bytes_proto; 4991 case BPF_FUNC_skb_pull_data: 4992 return &bpf_skb_pull_data_proto; 4993 case BPF_FUNC_csum_diff: 4994 return &bpf_csum_diff_proto; 4995 case BPF_FUNC_get_cgroup_classid: 4996 return &bpf_get_cgroup_classid_proto; 4997 case BPF_FUNC_get_route_realm: 4998 return &bpf_get_route_realm_proto; 4999 case BPF_FUNC_get_hash_recalc: 5000 return &bpf_get_hash_recalc_proto; 5001 case BPF_FUNC_perf_event_output: 5002 return &bpf_skb_event_output_proto; 5003 case BPF_FUNC_get_smp_processor_id: 5004 return &bpf_get_smp_processor_id_proto; 5005 case BPF_FUNC_skb_under_cgroup: 5006 return &bpf_skb_under_cgroup_proto; 5007 default: 5008 return bpf_base_func_proto(func_id); 5009 } 5010 } 5011 5012 static const struct bpf_func_proto * 5013 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5014 { 5015 switch (func_id) { 5016 case BPF_FUNC_lwt_push_encap: 5017 return &bpf_lwt_push_encap_proto; 5018 default: 5019 return lwt_out_func_proto(func_id, prog); 5020 } 5021 } 5022 5023 static const struct bpf_func_proto * 5024 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5025 { 5026 switch (func_id) { 5027 case BPF_FUNC_skb_get_tunnel_key: 5028 return &bpf_skb_get_tunnel_key_proto; 5029 case BPF_FUNC_skb_set_tunnel_key: 5030 return bpf_get_skb_set_tunnel_proto(func_id); 5031 case BPF_FUNC_skb_get_tunnel_opt: 5032 return &bpf_skb_get_tunnel_opt_proto; 5033 case BPF_FUNC_skb_set_tunnel_opt: 5034 return bpf_get_skb_set_tunnel_proto(func_id); 5035 case BPF_FUNC_redirect: 5036 return &bpf_redirect_proto; 5037 case BPF_FUNC_clone_redirect: 5038 return &bpf_clone_redirect_proto; 5039 case BPF_FUNC_skb_change_tail: 5040 return &bpf_skb_change_tail_proto; 5041 case BPF_FUNC_skb_change_head: 5042 return &bpf_skb_change_head_proto; 5043 case BPF_FUNC_skb_store_bytes: 5044 return &bpf_skb_store_bytes_proto; 5045 case BPF_FUNC_csum_update: 5046 return &bpf_csum_update_proto; 5047 case BPF_FUNC_l3_csum_replace: 5048 return &bpf_l3_csum_replace_proto; 5049 case BPF_FUNC_l4_csum_replace: 5050 return &bpf_l4_csum_replace_proto; 5051 case BPF_FUNC_set_hash_invalid: 5052 return &bpf_set_hash_invalid_proto; 5053 default: 5054 return lwt_out_func_proto(func_id, prog); 5055 } 5056 } 5057 5058 static const struct bpf_func_proto * 5059 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 5060 { 5061 switch (func_id) { 5062 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 5063 case BPF_FUNC_lwt_seg6_store_bytes: 5064 return &bpf_lwt_seg6_store_bytes_proto; 5065 case BPF_FUNC_lwt_seg6_action: 5066 return &bpf_lwt_seg6_action_proto; 5067 case BPF_FUNC_lwt_seg6_adjust_srh: 5068 return &bpf_lwt_seg6_adjust_srh_proto; 5069 #endif 5070 default: 5071 return lwt_out_func_proto(func_id, prog); 5072 } 5073 } 5074 5075 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type, 5076 const struct bpf_prog *prog, 5077 struct bpf_insn_access_aux *info) 5078 { 5079 const int size_default = sizeof(__u32); 5080 5081 if (off < 0 || off >= sizeof(struct __sk_buff)) 5082 return false; 5083 5084 /* The verifier guarantees that size > 0. */ 5085 if (off % size != 0) 5086 return false; 5087 5088 switch (off) { 5089 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5090 if (off + size > offsetofend(struct __sk_buff, cb[4])) 5091 return false; 5092 break; 5093 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]): 5094 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]): 5095 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4): 5096 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4): 5097 case bpf_ctx_range(struct __sk_buff, data): 5098 case bpf_ctx_range(struct __sk_buff, data_meta): 5099 case bpf_ctx_range(struct __sk_buff, data_end): 5100 if (size != size_default) 5101 return false; 5102 break; 5103 default: 5104 /* Only narrow read access allowed for now. */ 5105 if (type == BPF_WRITE) { 5106 if (size != size_default) 5107 return false; 5108 } else { 5109 bpf_ctx_record_field_size(info, size_default); 5110 if (!bpf_ctx_narrow_access_ok(off, size, size_default)) 5111 return false; 5112 } 5113 } 5114 5115 return true; 5116 } 5117 5118 static bool sk_filter_is_valid_access(int off, int size, 5119 enum bpf_access_type type, 5120 const struct bpf_prog *prog, 5121 struct bpf_insn_access_aux *info) 5122 { 5123 switch (off) { 5124 case bpf_ctx_range(struct __sk_buff, tc_classid): 5125 case bpf_ctx_range(struct __sk_buff, data): 5126 case bpf_ctx_range(struct __sk_buff, data_meta): 5127 case bpf_ctx_range(struct __sk_buff, data_end): 5128 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5129 return false; 5130 } 5131 5132 if (type == BPF_WRITE) { 5133 switch (off) { 5134 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5135 break; 5136 default: 5137 return false; 5138 } 5139 } 5140 5141 return bpf_skb_is_valid_access(off, size, type, prog, info); 5142 } 5143 5144 static bool lwt_is_valid_access(int off, int size, 5145 enum bpf_access_type type, 5146 const struct bpf_prog *prog, 5147 struct bpf_insn_access_aux *info) 5148 { 5149 switch (off) { 5150 case bpf_ctx_range(struct __sk_buff, tc_classid): 5151 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5152 case bpf_ctx_range(struct __sk_buff, data_meta): 5153 return false; 5154 } 5155 5156 if (type == BPF_WRITE) { 5157 switch (off) { 5158 case bpf_ctx_range(struct __sk_buff, mark): 5159 case bpf_ctx_range(struct __sk_buff, priority): 5160 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5161 break; 5162 default: 5163 return false; 5164 } 5165 } 5166 5167 switch (off) { 5168 case bpf_ctx_range(struct __sk_buff, data): 5169 info->reg_type = PTR_TO_PACKET; 5170 break; 5171 case bpf_ctx_range(struct __sk_buff, data_end): 5172 info->reg_type = PTR_TO_PACKET_END; 5173 break; 5174 } 5175 5176 return bpf_skb_is_valid_access(off, size, type, prog, info); 5177 } 5178 5179 /* Attach type specific accesses */ 5180 static bool __sock_filter_check_attach_type(int off, 5181 enum bpf_access_type access_type, 5182 enum bpf_attach_type attach_type) 5183 { 5184 switch (off) { 5185 case offsetof(struct bpf_sock, bound_dev_if): 5186 case offsetof(struct bpf_sock, mark): 5187 case offsetof(struct bpf_sock, priority): 5188 switch (attach_type) { 5189 case BPF_CGROUP_INET_SOCK_CREATE: 5190 goto full_access; 5191 default: 5192 return false; 5193 } 5194 case bpf_ctx_range(struct bpf_sock, src_ip4): 5195 switch (attach_type) { 5196 case BPF_CGROUP_INET4_POST_BIND: 5197 goto read_only; 5198 default: 5199 return false; 5200 } 5201 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5202 switch (attach_type) { 5203 case BPF_CGROUP_INET6_POST_BIND: 5204 goto read_only; 5205 default: 5206 return false; 5207 } 5208 case bpf_ctx_range(struct bpf_sock, src_port): 5209 switch (attach_type) { 5210 case BPF_CGROUP_INET4_POST_BIND: 5211 case BPF_CGROUP_INET6_POST_BIND: 5212 goto read_only; 5213 default: 5214 return false; 5215 } 5216 } 5217 read_only: 5218 return access_type == BPF_READ; 5219 full_access: 5220 return true; 5221 } 5222 5223 static bool __sock_filter_check_size(int off, int size, 5224 struct bpf_insn_access_aux *info) 5225 { 5226 const int size_default = sizeof(__u32); 5227 5228 switch (off) { 5229 case bpf_ctx_range(struct bpf_sock, src_ip4): 5230 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5231 bpf_ctx_record_field_size(info, size_default); 5232 return bpf_ctx_narrow_access_ok(off, size, size_default); 5233 } 5234 5235 return size == size_default; 5236 } 5237 5238 static bool sock_filter_is_valid_access(int off, int size, 5239 enum bpf_access_type type, 5240 const struct bpf_prog *prog, 5241 struct bpf_insn_access_aux *info) 5242 { 5243 if (off < 0 || off >= sizeof(struct bpf_sock)) 5244 return false; 5245 if (off % size != 0) 5246 return false; 5247 if (!__sock_filter_check_attach_type(off, type, 5248 prog->expected_attach_type)) 5249 return false; 5250 if (!__sock_filter_check_size(off, size, info)) 5251 return false; 5252 return true; 5253 } 5254 5255 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write, 5256 const struct bpf_prog *prog, int drop_verdict) 5257 { 5258 struct bpf_insn *insn = insn_buf; 5259 5260 if (!direct_write) 5261 return 0; 5262 5263 /* if (!skb->cloned) 5264 * goto start; 5265 * 5266 * (Fast-path, otherwise approximation that we might be 5267 * a clone, do the rest in helper.) 5268 */ 5269 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET()); 5270 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK); 5271 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7); 5272 5273 /* ret = bpf_skb_pull_data(skb, 0); */ 5274 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1); 5275 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2); 5276 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, 5277 BPF_FUNC_skb_pull_data); 5278 /* if (!ret) 5279 * goto restore; 5280 * return TC_ACT_SHOT; 5281 */ 5282 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2); 5283 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict); 5284 *insn++ = BPF_EXIT_INSN(); 5285 5286 /* restore: */ 5287 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6); 5288 /* start: */ 5289 *insn++ = prog->insnsi[0]; 5290 5291 return insn - insn_buf; 5292 } 5293 5294 static int bpf_gen_ld_abs(const struct bpf_insn *orig, 5295 struct bpf_insn *insn_buf) 5296 { 5297 bool indirect = BPF_MODE(orig->code) == BPF_IND; 5298 struct bpf_insn *insn = insn_buf; 5299 5300 /* We're guaranteed here that CTX is in R6. */ 5301 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX); 5302 if (!indirect) { 5303 *insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm); 5304 } else { 5305 *insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg); 5306 if (orig->imm) 5307 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm); 5308 } 5309 5310 switch (BPF_SIZE(orig->code)) { 5311 case BPF_B: 5312 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache); 5313 break; 5314 case BPF_H: 5315 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache); 5316 break; 5317 case BPF_W: 5318 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache); 5319 break; 5320 } 5321 5322 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2); 5323 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0); 5324 *insn++ = BPF_EXIT_INSN(); 5325 5326 return insn - insn_buf; 5327 } 5328 5329 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, 5330 const struct bpf_prog *prog) 5331 { 5332 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT); 5333 } 5334 5335 static bool tc_cls_act_is_valid_access(int off, int size, 5336 enum bpf_access_type type, 5337 const struct bpf_prog *prog, 5338 struct bpf_insn_access_aux *info) 5339 { 5340 if (type == BPF_WRITE) { 5341 switch (off) { 5342 case bpf_ctx_range(struct __sk_buff, mark): 5343 case bpf_ctx_range(struct __sk_buff, tc_index): 5344 case bpf_ctx_range(struct __sk_buff, priority): 5345 case bpf_ctx_range(struct __sk_buff, tc_classid): 5346 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5347 break; 5348 default: 5349 return false; 5350 } 5351 } 5352 5353 switch (off) { 5354 case bpf_ctx_range(struct __sk_buff, data): 5355 info->reg_type = PTR_TO_PACKET; 5356 break; 5357 case bpf_ctx_range(struct __sk_buff, data_meta): 5358 info->reg_type = PTR_TO_PACKET_META; 5359 break; 5360 case bpf_ctx_range(struct __sk_buff, data_end): 5361 info->reg_type = PTR_TO_PACKET_END; 5362 break; 5363 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5364 return false; 5365 } 5366 5367 return bpf_skb_is_valid_access(off, size, type, prog, info); 5368 } 5369 5370 static bool __is_valid_xdp_access(int off, int size) 5371 { 5372 if (off < 0 || off >= sizeof(struct xdp_md)) 5373 return false; 5374 if (off % size != 0) 5375 return false; 5376 if (size != sizeof(__u32)) 5377 return false; 5378 5379 return true; 5380 } 5381 5382 static bool xdp_is_valid_access(int off, int size, 5383 enum bpf_access_type type, 5384 const struct bpf_prog *prog, 5385 struct bpf_insn_access_aux *info) 5386 { 5387 if (type == BPF_WRITE) { 5388 if (bpf_prog_is_dev_bound(prog->aux)) { 5389 switch (off) { 5390 case offsetof(struct xdp_md, rx_queue_index): 5391 return __is_valid_xdp_access(off, size); 5392 } 5393 } 5394 return false; 5395 } 5396 5397 switch (off) { 5398 case offsetof(struct xdp_md, data): 5399 info->reg_type = PTR_TO_PACKET; 5400 break; 5401 case offsetof(struct xdp_md, data_meta): 5402 info->reg_type = PTR_TO_PACKET_META; 5403 break; 5404 case offsetof(struct xdp_md, data_end): 5405 info->reg_type = PTR_TO_PACKET_END; 5406 break; 5407 } 5408 5409 return __is_valid_xdp_access(off, size); 5410 } 5411 5412 void bpf_warn_invalid_xdp_action(u32 act) 5413 { 5414 const u32 act_max = XDP_REDIRECT; 5415 5416 WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n", 5417 act > act_max ? "Illegal" : "Driver unsupported", 5418 act); 5419 } 5420 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action); 5421 5422 static bool sock_addr_is_valid_access(int off, int size, 5423 enum bpf_access_type type, 5424 const struct bpf_prog *prog, 5425 struct bpf_insn_access_aux *info) 5426 { 5427 const int size_default = sizeof(__u32); 5428 5429 if (off < 0 || off >= sizeof(struct bpf_sock_addr)) 5430 return false; 5431 if (off % size != 0) 5432 return false; 5433 5434 /* Disallow access to IPv6 fields from IPv4 contex and vise 5435 * versa. 5436 */ 5437 switch (off) { 5438 case bpf_ctx_range(struct bpf_sock_addr, user_ip4): 5439 switch (prog->expected_attach_type) { 5440 case BPF_CGROUP_INET4_BIND: 5441 case BPF_CGROUP_INET4_CONNECT: 5442 case BPF_CGROUP_UDP4_SENDMSG: 5443 break; 5444 default: 5445 return false; 5446 } 5447 break; 5448 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 5449 switch (prog->expected_attach_type) { 5450 case BPF_CGROUP_INET6_BIND: 5451 case BPF_CGROUP_INET6_CONNECT: 5452 case BPF_CGROUP_UDP6_SENDMSG: 5453 break; 5454 default: 5455 return false; 5456 } 5457 break; 5458 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4): 5459 switch (prog->expected_attach_type) { 5460 case BPF_CGROUP_UDP4_SENDMSG: 5461 break; 5462 default: 5463 return false; 5464 } 5465 break; 5466 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 5467 msg_src_ip6[3]): 5468 switch (prog->expected_attach_type) { 5469 case BPF_CGROUP_UDP6_SENDMSG: 5470 break; 5471 default: 5472 return false; 5473 } 5474 break; 5475 } 5476 5477 switch (off) { 5478 case bpf_ctx_range(struct bpf_sock_addr, user_ip4): 5479 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 5480 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4): 5481 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 5482 msg_src_ip6[3]): 5483 /* Only narrow read access allowed for now. */ 5484 if (type == BPF_READ) { 5485 bpf_ctx_record_field_size(info, size_default); 5486 if (!bpf_ctx_narrow_access_ok(off, size, size_default)) 5487 return false; 5488 } else { 5489 if (size != size_default) 5490 return false; 5491 } 5492 break; 5493 case bpf_ctx_range(struct bpf_sock_addr, user_port): 5494 if (size != size_default) 5495 return false; 5496 break; 5497 default: 5498 if (type == BPF_READ) { 5499 if (size != size_default) 5500 return false; 5501 } else { 5502 return false; 5503 } 5504 } 5505 5506 return true; 5507 } 5508 5509 static bool sock_ops_is_valid_access(int off, int size, 5510 enum bpf_access_type type, 5511 const struct bpf_prog *prog, 5512 struct bpf_insn_access_aux *info) 5513 { 5514 const int size_default = sizeof(__u32); 5515 5516 if (off < 0 || off >= sizeof(struct bpf_sock_ops)) 5517 return false; 5518 5519 /* The verifier guarantees that size > 0. */ 5520 if (off % size != 0) 5521 return false; 5522 5523 if (type == BPF_WRITE) { 5524 switch (off) { 5525 case offsetof(struct bpf_sock_ops, reply): 5526 case offsetof(struct bpf_sock_ops, sk_txhash): 5527 if (size != size_default) 5528 return false; 5529 break; 5530 default: 5531 return false; 5532 } 5533 } else { 5534 switch (off) { 5535 case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received, 5536 bytes_acked): 5537 if (size != sizeof(__u64)) 5538 return false; 5539 break; 5540 default: 5541 if (size != size_default) 5542 return false; 5543 break; 5544 } 5545 } 5546 5547 return true; 5548 } 5549 5550 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write, 5551 const struct bpf_prog *prog) 5552 { 5553 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP); 5554 } 5555 5556 static bool sk_skb_is_valid_access(int off, int size, 5557 enum bpf_access_type type, 5558 const struct bpf_prog *prog, 5559 struct bpf_insn_access_aux *info) 5560 { 5561 switch (off) { 5562 case bpf_ctx_range(struct __sk_buff, tc_classid): 5563 case bpf_ctx_range(struct __sk_buff, data_meta): 5564 return false; 5565 } 5566 5567 if (type == BPF_WRITE) { 5568 switch (off) { 5569 case bpf_ctx_range(struct __sk_buff, tc_index): 5570 case bpf_ctx_range(struct __sk_buff, priority): 5571 break; 5572 default: 5573 return false; 5574 } 5575 } 5576 5577 switch (off) { 5578 case bpf_ctx_range(struct __sk_buff, mark): 5579 return false; 5580 case bpf_ctx_range(struct __sk_buff, data): 5581 info->reg_type = PTR_TO_PACKET; 5582 break; 5583 case bpf_ctx_range(struct __sk_buff, data_end): 5584 info->reg_type = PTR_TO_PACKET_END; 5585 break; 5586 } 5587 5588 return bpf_skb_is_valid_access(off, size, type, prog, info); 5589 } 5590 5591 static bool sk_msg_is_valid_access(int off, int size, 5592 enum bpf_access_type type, 5593 const struct bpf_prog *prog, 5594 struct bpf_insn_access_aux *info) 5595 { 5596 if (type == BPF_WRITE) 5597 return false; 5598 5599 switch (off) { 5600 case offsetof(struct sk_msg_md, data): 5601 info->reg_type = PTR_TO_PACKET; 5602 if (size != sizeof(__u64)) 5603 return false; 5604 break; 5605 case offsetof(struct sk_msg_md, data_end): 5606 info->reg_type = PTR_TO_PACKET_END; 5607 if (size != sizeof(__u64)) 5608 return false; 5609 break; 5610 default: 5611 if (size != sizeof(__u32)) 5612 return false; 5613 } 5614 5615 if (off < 0 || off >= sizeof(struct sk_msg_md)) 5616 return false; 5617 if (off % size != 0) 5618 return false; 5619 5620 return true; 5621 } 5622 5623 static u32 bpf_convert_ctx_access(enum bpf_access_type type, 5624 const struct bpf_insn *si, 5625 struct bpf_insn *insn_buf, 5626 struct bpf_prog *prog, u32 *target_size) 5627 { 5628 struct bpf_insn *insn = insn_buf; 5629 int off; 5630 5631 switch (si->off) { 5632 case offsetof(struct __sk_buff, len): 5633 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5634 bpf_target_off(struct sk_buff, len, 4, 5635 target_size)); 5636 break; 5637 5638 case offsetof(struct __sk_buff, protocol): 5639 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5640 bpf_target_off(struct sk_buff, protocol, 2, 5641 target_size)); 5642 break; 5643 5644 case offsetof(struct __sk_buff, vlan_proto): 5645 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5646 bpf_target_off(struct sk_buff, vlan_proto, 2, 5647 target_size)); 5648 break; 5649 5650 case offsetof(struct __sk_buff, priority): 5651 if (type == BPF_WRITE) 5652 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5653 bpf_target_off(struct sk_buff, priority, 4, 5654 target_size)); 5655 else 5656 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5657 bpf_target_off(struct sk_buff, priority, 4, 5658 target_size)); 5659 break; 5660 5661 case offsetof(struct __sk_buff, ingress_ifindex): 5662 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5663 bpf_target_off(struct sk_buff, skb_iif, 4, 5664 target_size)); 5665 break; 5666 5667 case offsetof(struct __sk_buff, ifindex): 5668 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 5669 si->dst_reg, si->src_reg, 5670 offsetof(struct sk_buff, dev)); 5671 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1); 5672 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5673 bpf_target_off(struct net_device, ifindex, 4, 5674 target_size)); 5675 break; 5676 5677 case offsetof(struct __sk_buff, hash): 5678 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5679 bpf_target_off(struct sk_buff, hash, 4, 5680 target_size)); 5681 break; 5682 5683 case offsetof(struct __sk_buff, mark): 5684 if (type == BPF_WRITE) 5685 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5686 bpf_target_off(struct sk_buff, mark, 4, 5687 target_size)); 5688 else 5689 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5690 bpf_target_off(struct sk_buff, mark, 4, 5691 target_size)); 5692 break; 5693 5694 case offsetof(struct __sk_buff, pkt_type): 5695 *target_size = 1; 5696 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg, 5697 PKT_TYPE_OFFSET()); 5698 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX); 5699 #ifdef __BIG_ENDIAN_BITFIELD 5700 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5); 5701 #endif 5702 break; 5703 5704 case offsetof(struct __sk_buff, queue_mapping): 5705 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5706 bpf_target_off(struct sk_buff, queue_mapping, 2, 5707 target_size)); 5708 break; 5709 5710 case offsetof(struct __sk_buff, vlan_present): 5711 case offsetof(struct __sk_buff, vlan_tci): 5712 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); 5713 5714 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5715 bpf_target_off(struct sk_buff, vlan_tci, 2, 5716 target_size)); 5717 if (si->off == offsetof(struct __sk_buff, vlan_tci)) { 5718 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 5719 ~VLAN_TAG_PRESENT); 5720 } else { 5721 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12); 5722 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1); 5723 } 5724 break; 5725 5726 case offsetof(struct __sk_buff, cb[0]) ... 5727 offsetofend(struct __sk_buff, cb[4]) - 1: 5728 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20); 5729 BUILD_BUG_ON((offsetof(struct sk_buff, cb) + 5730 offsetof(struct qdisc_skb_cb, data)) % 5731 sizeof(__u64)); 5732 5733 prog->cb_access = 1; 5734 off = si->off; 5735 off -= offsetof(struct __sk_buff, cb[0]); 5736 off += offsetof(struct sk_buff, cb); 5737 off += offsetof(struct qdisc_skb_cb, data); 5738 if (type == BPF_WRITE) 5739 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg, 5740 si->src_reg, off); 5741 else 5742 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg, 5743 si->src_reg, off); 5744 break; 5745 5746 case offsetof(struct __sk_buff, tc_classid): 5747 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2); 5748 5749 off = si->off; 5750 off -= offsetof(struct __sk_buff, tc_classid); 5751 off += offsetof(struct sk_buff, cb); 5752 off += offsetof(struct qdisc_skb_cb, tc_classid); 5753 *target_size = 2; 5754 if (type == BPF_WRITE) 5755 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, 5756 si->src_reg, off); 5757 else 5758 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, 5759 si->src_reg, off); 5760 break; 5761 5762 case offsetof(struct __sk_buff, data): 5763 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data), 5764 si->dst_reg, si->src_reg, 5765 offsetof(struct sk_buff, data)); 5766 break; 5767 5768 case offsetof(struct __sk_buff, data_meta): 5769 off = si->off; 5770 off -= offsetof(struct __sk_buff, data_meta); 5771 off += offsetof(struct sk_buff, cb); 5772 off += offsetof(struct bpf_skb_data_end, data_meta); 5773 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 5774 si->src_reg, off); 5775 break; 5776 5777 case offsetof(struct __sk_buff, data_end): 5778 off = si->off; 5779 off -= offsetof(struct __sk_buff, data_end); 5780 off += offsetof(struct sk_buff, cb); 5781 off += offsetof(struct bpf_skb_data_end, data_end); 5782 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 5783 si->src_reg, off); 5784 break; 5785 5786 case offsetof(struct __sk_buff, tc_index): 5787 #ifdef CONFIG_NET_SCHED 5788 if (type == BPF_WRITE) 5789 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg, 5790 bpf_target_off(struct sk_buff, tc_index, 2, 5791 target_size)); 5792 else 5793 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5794 bpf_target_off(struct sk_buff, tc_index, 2, 5795 target_size)); 5796 #else 5797 *target_size = 2; 5798 if (type == BPF_WRITE) 5799 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg); 5800 else 5801 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 5802 #endif 5803 break; 5804 5805 case offsetof(struct __sk_buff, napi_id): 5806 #if defined(CONFIG_NET_RX_BUSY_POLL) 5807 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5808 bpf_target_off(struct sk_buff, napi_id, 4, 5809 target_size)); 5810 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1); 5811 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 5812 #else 5813 *target_size = 4; 5814 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 5815 #endif 5816 break; 5817 case offsetof(struct __sk_buff, family): 5818 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 5819 5820 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5821 si->dst_reg, si->src_reg, 5822 offsetof(struct sk_buff, sk)); 5823 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 5824 bpf_target_off(struct sock_common, 5825 skc_family, 5826 2, target_size)); 5827 break; 5828 case offsetof(struct __sk_buff, remote_ip4): 5829 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 5830 5831 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5832 si->dst_reg, si->src_reg, 5833 offsetof(struct sk_buff, sk)); 5834 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5835 bpf_target_off(struct sock_common, 5836 skc_daddr, 5837 4, target_size)); 5838 break; 5839 case offsetof(struct __sk_buff, local_ip4): 5840 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 5841 skc_rcv_saddr) != 4); 5842 5843 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5844 si->dst_reg, si->src_reg, 5845 offsetof(struct sk_buff, sk)); 5846 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5847 bpf_target_off(struct sock_common, 5848 skc_rcv_saddr, 5849 4, target_size)); 5850 break; 5851 case offsetof(struct __sk_buff, remote_ip6[0]) ... 5852 offsetof(struct __sk_buff, remote_ip6[3]): 5853 #if IS_ENABLED(CONFIG_IPV6) 5854 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 5855 skc_v6_daddr.s6_addr32[0]) != 4); 5856 5857 off = si->off; 5858 off -= offsetof(struct __sk_buff, remote_ip6[0]); 5859 5860 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5861 si->dst_reg, si->src_reg, 5862 offsetof(struct sk_buff, sk)); 5863 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5864 offsetof(struct sock_common, 5865 skc_v6_daddr.s6_addr32[0]) + 5866 off); 5867 #else 5868 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 5869 #endif 5870 break; 5871 case offsetof(struct __sk_buff, local_ip6[0]) ... 5872 offsetof(struct __sk_buff, local_ip6[3]): 5873 #if IS_ENABLED(CONFIG_IPV6) 5874 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 5875 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 5876 5877 off = si->off; 5878 off -= offsetof(struct __sk_buff, local_ip6[0]); 5879 5880 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5881 si->dst_reg, si->src_reg, 5882 offsetof(struct sk_buff, sk)); 5883 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5884 offsetof(struct sock_common, 5885 skc_v6_rcv_saddr.s6_addr32[0]) + 5886 off); 5887 #else 5888 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 5889 #endif 5890 break; 5891 5892 case offsetof(struct __sk_buff, remote_port): 5893 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 5894 5895 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5896 si->dst_reg, si->src_reg, 5897 offsetof(struct sk_buff, sk)); 5898 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 5899 bpf_target_off(struct sock_common, 5900 skc_dport, 5901 2, target_size)); 5902 #ifndef __BIG_ENDIAN_BITFIELD 5903 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 5904 #endif 5905 break; 5906 5907 case offsetof(struct __sk_buff, local_port): 5908 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 5909 5910 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5911 si->dst_reg, si->src_reg, 5912 offsetof(struct sk_buff, sk)); 5913 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 5914 bpf_target_off(struct sock_common, 5915 skc_num, 2, target_size)); 5916 break; 5917 } 5918 5919 return insn - insn_buf; 5920 } 5921 5922 static u32 sock_filter_convert_ctx_access(enum bpf_access_type type, 5923 const struct bpf_insn *si, 5924 struct bpf_insn *insn_buf, 5925 struct bpf_prog *prog, u32 *target_size) 5926 { 5927 struct bpf_insn *insn = insn_buf; 5928 int off; 5929 5930 switch (si->off) { 5931 case offsetof(struct bpf_sock, bound_dev_if): 5932 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4); 5933 5934 if (type == BPF_WRITE) 5935 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5936 offsetof(struct sock, sk_bound_dev_if)); 5937 else 5938 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5939 offsetof(struct sock, sk_bound_dev_if)); 5940 break; 5941 5942 case offsetof(struct bpf_sock, mark): 5943 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4); 5944 5945 if (type == BPF_WRITE) 5946 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5947 offsetof(struct sock, sk_mark)); 5948 else 5949 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5950 offsetof(struct sock, sk_mark)); 5951 break; 5952 5953 case offsetof(struct bpf_sock, priority): 5954 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4); 5955 5956 if (type == BPF_WRITE) 5957 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5958 offsetof(struct sock, sk_priority)); 5959 else 5960 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5961 offsetof(struct sock, sk_priority)); 5962 break; 5963 5964 case offsetof(struct bpf_sock, family): 5965 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2); 5966 5967 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5968 offsetof(struct sock, sk_family)); 5969 break; 5970 5971 case offsetof(struct bpf_sock, type): 5972 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5973 offsetof(struct sock, __sk_flags_offset)); 5974 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK); 5975 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT); 5976 break; 5977 5978 case offsetof(struct bpf_sock, protocol): 5979 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5980 offsetof(struct sock, __sk_flags_offset)); 5981 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK); 5982 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT); 5983 break; 5984 5985 case offsetof(struct bpf_sock, src_ip4): 5986 *insn++ = BPF_LDX_MEM( 5987 BPF_SIZE(si->code), si->dst_reg, si->src_reg, 5988 bpf_target_off(struct sock_common, skc_rcv_saddr, 5989 FIELD_SIZEOF(struct sock_common, 5990 skc_rcv_saddr), 5991 target_size)); 5992 break; 5993 5994 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5995 #if IS_ENABLED(CONFIG_IPV6) 5996 off = si->off; 5997 off -= offsetof(struct bpf_sock, src_ip6[0]); 5998 *insn++ = BPF_LDX_MEM( 5999 BPF_SIZE(si->code), si->dst_reg, si->src_reg, 6000 bpf_target_off( 6001 struct sock_common, 6002 skc_v6_rcv_saddr.s6_addr32[0], 6003 FIELD_SIZEOF(struct sock_common, 6004 skc_v6_rcv_saddr.s6_addr32[0]), 6005 target_size) + off); 6006 #else 6007 (void)off; 6008 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6009 #endif 6010 break; 6011 6012 case offsetof(struct bpf_sock, src_port): 6013 *insn++ = BPF_LDX_MEM( 6014 BPF_FIELD_SIZEOF(struct sock_common, skc_num), 6015 si->dst_reg, si->src_reg, 6016 bpf_target_off(struct sock_common, skc_num, 6017 FIELD_SIZEOF(struct sock_common, 6018 skc_num), 6019 target_size)); 6020 break; 6021 } 6022 6023 return insn - insn_buf; 6024 } 6025 6026 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type, 6027 const struct bpf_insn *si, 6028 struct bpf_insn *insn_buf, 6029 struct bpf_prog *prog, u32 *target_size) 6030 { 6031 struct bpf_insn *insn = insn_buf; 6032 6033 switch (si->off) { 6034 case offsetof(struct __sk_buff, ifindex): 6035 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 6036 si->dst_reg, si->src_reg, 6037 offsetof(struct sk_buff, dev)); 6038 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6039 bpf_target_off(struct net_device, ifindex, 4, 6040 target_size)); 6041 break; 6042 default: 6043 return bpf_convert_ctx_access(type, si, insn_buf, prog, 6044 target_size); 6045 } 6046 6047 return insn - insn_buf; 6048 } 6049 6050 static u32 xdp_convert_ctx_access(enum bpf_access_type type, 6051 const struct bpf_insn *si, 6052 struct bpf_insn *insn_buf, 6053 struct bpf_prog *prog, u32 *target_size) 6054 { 6055 struct bpf_insn *insn = insn_buf; 6056 6057 switch (si->off) { 6058 case offsetof(struct xdp_md, data): 6059 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data), 6060 si->dst_reg, si->src_reg, 6061 offsetof(struct xdp_buff, data)); 6062 break; 6063 case offsetof(struct xdp_md, data_meta): 6064 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta), 6065 si->dst_reg, si->src_reg, 6066 offsetof(struct xdp_buff, data_meta)); 6067 break; 6068 case offsetof(struct xdp_md, data_end): 6069 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end), 6070 si->dst_reg, si->src_reg, 6071 offsetof(struct xdp_buff, data_end)); 6072 break; 6073 case offsetof(struct xdp_md, ingress_ifindex): 6074 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq), 6075 si->dst_reg, si->src_reg, 6076 offsetof(struct xdp_buff, rxq)); 6077 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev), 6078 si->dst_reg, si->dst_reg, 6079 offsetof(struct xdp_rxq_info, dev)); 6080 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6081 offsetof(struct net_device, ifindex)); 6082 break; 6083 case offsetof(struct xdp_md, rx_queue_index): 6084 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq), 6085 si->dst_reg, si->src_reg, 6086 offsetof(struct xdp_buff, rxq)); 6087 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6088 offsetof(struct xdp_rxq_info, 6089 queue_index)); 6090 break; 6091 } 6092 6093 return insn - insn_buf; 6094 } 6095 6096 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of 6097 * context Structure, F is Field in context structure that contains a pointer 6098 * to Nested Structure of type NS that has the field NF. 6099 * 6100 * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make 6101 * sure that SIZE is not greater than actual size of S.F.NF. 6102 * 6103 * If offset OFF is provided, the load happens from that offset relative to 6104 * offset of NF. 6105 */ 6106 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF) \ 6107 do { \ 6108 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg, \ 6109 si->src_reg, offsetof(S, F)); \ 6110 *insn++ = BPF_LDX_MEM( \ 6111 SIZE, si->dst_reg, si->dst_reg, \ 6112 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \ 6113 target_size) \ 6114 + OFF); \ 6115 } while (0) 6116 6117 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF) \ 6118 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, \ 6119 BPF_FIELD_SIZEOF(NS, NF), 0) 6120 6121 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to 6122 * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation. 6123 * 6124 * It doesn't support SIZE argument though since narrow stores are not 6125 * supported for now. 6126 * 6127 * In addition it uses Temporary Field TF (member of struct S) as the 3rd 6128 * "register" since two registers available in convert_ctx_access are not 6129 * enough: we can't override neither SRC, since it contains value to store, nor 6130 * DST since it contains pointer to context that may be used by later 6131 * instructions. But we need a temporary place to save pointer to nested 6132 * structure whose field we want to store to. 6133 */ 6134 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, TF) \ 6135 do { \ 6136 int tmp_reg = BPF_REG_9; \ 6137 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \ 6138 --tmp_reg; \ 6139 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \ 6140 --tmp_reg; \ 6141 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg, \ 6142 offsetof(S, TF)); \ 6143 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg, \ 6144 si->dst_reg, offsetof(S, F)); \ 6145 *insn++ = BPF_STX_MEM( \ 6146 BPF_FIELD_SIZEOF(NS, NF), tmp_reg, si->src_reg, \ 6147 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \ 6148 target_size) \ 6149 + OFF); \ 6150 *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg, \ 6151 offsetof(S, TF)); \ 6152 } while (0) 6153 6154 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \ 6155 TF) \ 6156 do { \ 6157 if (type == BPF_WRITE) { \ 6158 SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, \ 6159 TF); \ 6160 } else { \ 6161 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( \ 6162 S, NS, F, NF, SIZE, OFF); \ 6163 } \ 6164 } while (0) 6165 6166 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF) \ 6167 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( \ 6168 S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF) 6169 6170 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type, 6171 const struct bpf_insn *si, 6172 struct bpf_insn *insn_buf, 6173 struct bpf_prog *prog, u32 *target_size) 6174 { 6175 struct bpf_insn *insn = insn_buf; 6176 int off; 6177 6178 switch (si->off) { 6179 case offsetof(struct bpf_sock_addr, user_family): 6180 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern, 6181 struct sockaddr, uaddr, sa_family); 6182 break; 6183 6184 case offsetof(struct bpf_sock_addr, user_ip4): 6185 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6186 struct bpf_sock_addr_kern, struct sockaddr_in, uaddr, 6187 sin_addr, BPF_SIZE(si->code), 0, tmp_reg); 6188 break; 6189 6190 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 6191 off = si->off; 6192 off -= offsetof(struct bpf_sock_addr, user_ip6[0]); 6193 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6194 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr, 6195 sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off, 6196 tmp_reg); 6197 break; 6198 6199 case offsetof(struct bpf_sock_addr, user_port): 6200 /* To get port we need to know sa_family first and then treat 6201 * sockaddr as either sockaddr_in or sockaddr_in6. 6202 * Though we can simplify since port field has same offset and 6203 * size in both structures. 6204 * Here we check this invariant and use just one of the 6205 * structures if it's true. 6206 */ 6207 BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) != 6208 offsetof(struct sockaddr_in6, sin6_port)); 6209 BUILD_BUG_ON(FIELD_SIZEOF(struct sockaddr_in, sin_port) != 6210 FIELD_SIZEOF(struct sockaddr_in6, sin6_port)); 6211 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(struct bpf_sock_addr_kern, 6212 struct sockaddr_in6, uaddr, 6213 sin6_port, tmp_reg); 6214 break; 6215 6216 case offsetof(struct bpf_sock_addr, family): 6217 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern, 6218 struct sock, sk, sk_family); 6219 break; 6220 6221 case offsetof(struct bpf_sock_addr, type): 6222 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( 6223 struct bpf_sock_addr_kern, struct sock, sk, 6224 __sk_flags_offset, BPF_W, 0); 6225 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK); 6226 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT); 6227 break; 6228 6229 case offsetof(struct bpf_sock_addr, protocol): 6230 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( 6231 struct bpf_sock_addr_kern, struct sock, sk, 6232 __sk_flags_offset, BPF_W, 0); 6233 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK); 6234 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 6235 SK_FL_PROTO_SHIFT); 6236 break; 6237 6238 case offsetof(struct bpf_sock_addr, msg_src_ip4): 6239 /* Treat t_ctx as struct in_addr for msg_src_ip4. */ 6240 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6241 struct bpf_sock_addr_kern, struct in_addr, t_ctx, 6242 s_addr, BPF_SIZE(si->code), 0, tmp_reg); 6243 break; 6244 6245 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 6246 msg_src_ip6[3]): 6247 off = si->off; 6248 off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]); 6249 /* Treat t_ctx as struct in6_addr for msg_src_ip6. */ 6250 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6251 struct bpf_sock_addr_kern, struct in6_addr, t_ctx, 6252 s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg); 6253 break; 6254 } 6255 6256 return insn - insn_buf; 6257 } 6258 6259 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, 6260 const struct bpf_insn *si, 6261 struct bpf_insn *insn_buf, 6262 struct bpf_prog *prog, 6263 u32 *target_size) 6264 { 6265 struct bpf_insn *insn = insn_buf; 6266 int off; 6267 6268 switch (si->off) { 6269 case offsetof(struct bpf_sock_ops, op) ... 6270 offsetof(struct bpf_sock_ops, replylong[3]): 6271 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) != 6272 FIELD_SIZEOF(struct bpf_sock_ops_kern, op)); 6273 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) != 6274 FIELD_SIZEOF(struct bpf_sock_ops_kern, reply)); 6275 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) != 6276 FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong)); 6277 off = si->off; 6278 off -= offsetof(struct bpf_sock_ops, op); 6279 off += offsetof(struct bpf_sock_ops_kern, op); 6280 if (type == BPF_WRITE) 6281 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6282 off); 6283 else 6284 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6285 off); 6286 break; 6287 6288 case offsetof(struct bpf_sock_ops, family): 6289 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 6290 6291 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6292 struct bpf_sock_ops_kern, sk), 6293 si->dst_reg, si->src_reg, 6294 offsetof(struct bpf_sock_ops_kern, sk)); 6295 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6296 offsetof(struct sock_common, skc_family)); 6297 break; 6298 6299 case offsetof(struct bpf_sock_ops, remote_ip4): 6300 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 6301 6302 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6303 struct bpf_sock_ops_kern, sk), 6304 si->dst_reg, si->src_reg, 6305 offsetof(struct bpf_sock_ops_kern, sk)); 6306 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6307 offsetof(struct sock_common, skc_daddr)); 6308 break; 6309 6310 case offsetof(struct bpf_sock_ops, local_ip4): 6311 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6312 skc_rcv_saddr) != 4); 6313 6314 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6315 struct bpf_sock_ops_kern, sk), 6316 si->dst_reg, si->src_reg, 6317 offsetof(struct bpf_sock_ops_kern, sk)); 6318 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6319 offsetof(struct sock_common, 6320 skc_rcv_saddr)); 6321 break; 6322 6323 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ... 6324 offsetof(struct bpf_sock_ops, remote_ip6[3]): 6325 #if IS_ENABLED(CONFIG_IPV6) 6326 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6327 skc_v6_daddr.s6_addr32[0]) != 4); 6328 6329 off = si->off; 6330 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]); 6331 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6332 struct bpf_sock_ops_kern, sk), 6333 si->dst_reg, si->src_reg, 6334 offsetof(struct bpf_sock_ops_kern, sk)); 6335 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6336 offsetof(struct sock_common, 6337 skc_v6_daddr.s6_addr32[0]) + 6338 off); 6339 #else 6340 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6341 #endif 6342 break; 6343 6344 case offsetof(struct bpf_sock_ops, local_ip6[0]) ... 6345 offsetof(struct bpf_sock_ops, local_ip6[3]): 6346 #if IS_ENABLED(CONFIG_IPV6) 6347 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6348 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 6349 6350 off = si->off; 6351 off -= offsetof(struct bpf_sock_ops, local_ip6[0]); 6352 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6353 struct bpf_sock_ops_kern, sk), 6354 si->dst_reg, si->src_reg, 6355 offsetof(struct bpf_sock_ops_kern, sk)); 6356 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6357 offsetof(struct sock_common, 6358 skc_v6_rcv_saddr.s6_addr32[0]) + 6359 off); 6360 #else 6361 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6362 #endif 6363 break; 6364 6365 case offsetof(struct bpf_sock_ops, remote_port): 6366 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 6367 6368 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6369 struct bpf_sock_ops_kern, sk), 6370 si->dst_reg, si->src_reg, 6371 offsetof(struct bpf_sock_ops_kern, sk)); 6372 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6373 offsetof(struct sock_common, skc_dport)); 6374 #ifndef __BIG_ENDIAN_BITFIELD 6375 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 6376 #endif 6377 break; 6378 6379 case offsetof(struct bpf_sock_ops, local_port): 6380 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 6381 6382 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6383 struct bpf_sock_ops_kern, sk), 6384 si->dst_reg, si->src_reg, 6385 offsetof(struct bpf_sock_ops_kern, sk)); 6386 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6387 offsetof(struct sock_common, skc_num)); 6388 break; 6389 6390 case offsetof(struct bpf_sock_ops, is_fullsock): 6391 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6392 struct bpf_sock_ops_kern, 6393 is_fullsock), 6394 si->dst_reg, si->src_reg, 6395 offsetof(struct bpf_sock_ops_kern, 6396 is_fullsock)); 6397 break; 6398 6399 case offsetof(struct bpf_sock_ops, state): 6400 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_state) != 1); 6401 6402 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6403 struct bpf_sock_ops_kern, sk), 6404 si->dst_reg, si->src_reg, 6405 offsetof(struct bpf_sock_ops_kern, sk)); 6406 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg, 6407 offsetof(struct sock_common, skc_state)); 6408 break; 6409 6410 case offsetof(struct bpf_sock_ops, rtt_min): 6411 BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, rtt_min) != 6412 sizeof(struct minmax)); 6413 BUILD_BUG_ON(sizeof(struct minmax) < 6414 sizeof(struct minmax_sample)); 6415 6416 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6417 struct bpf_sock_ops_kern, sk), 6418 si->dst_reg, si->src_reg, 6419 offsetof(struct bpf_sock_ops_kern, sk)); 6420 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6421 offsetof(struct tcp_sock, rtt_min) + 6422 FIELD_SIZEOF(struct minmax_sample, t)); 6423 break; 6424 6425 /* Helper macro for adding read access to tcp_sock or sock fields. */ 6426 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \ 6427 do { \ 6428 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \ 6429 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \ 6430 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6431 struct bpf_sock_ops_kern, \ 6432 is_fullsock), \ 6433 si->dst_reg, si->src_reg, \ 6434 offsetof(struct bpf_sock_ops_kern, \ 6435 is_fullsock)); \ 6436 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 2); \ 6437 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6438 struct bpf_sock_ops_kern, sk),\ 6439 si->dst_reg, si->src_reg, \ 6440 offsetof(struct bpf_sock_ops_kern, sk));\ 6441 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ, \ 6442 OBJ_FIELD), \ 6443 si->dst_reg, si->dst_reg, \ 6444 offsetof(OBJ, OBJ_FIELD)); \ 6445 } while (0) 6446 6447 /* Helper macro for adding write access to tcp_sock or sock fields. 6448 * The macro is called with two registers, dst_reg which contains a pointer 6449 * to ctx (context) and src_reg which contains the value that should be 6450 * stored. However, we need an additional register since we cannot overwrite 6451 * dst_reg because it may be used later in the program. 6452 * Instead we "borrow" one of the other register. We first save its value 6453 * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore 6454 * it at the end of the macro. 6455 */ 6456 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \ 6457 do { \ 6458 int reg = BPF_REG_9; \ 6459 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \ 6460 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \ 6461 if (si->dst_reg == reg || si->src_reg == reg) \ 6462 reg--; \ 6463 if (si->dst_reg == reg || si->src_reg == reg) \ 6464 reg--; \ 6465 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg, \ 6466 offsetof(struct bpf_sock_ops_kern, \ 6467 temp)); \ 6468 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6469 struct bpf_sock_ops_kern, \ 6470 is_fullsock), \ 6471 reg, si->dst_reg, \ 6472 offsetof(struct bpf_sock_ops_kern, \ 6473 is_fullsock)); \ 6474 *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2); \ 6475 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6476 struct bpf_sock_ops_kern, sk),\ 6477 reg, si->dst_reg, \ 6478 offsetof(struct bpf_sock_ops_kern, sk));\ 6479 *insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD), \ 6480 reg, si->src_reg, \ 6481 offsetof(OBJ, OBJ_FIELD)); \ 6482 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg, \ 6483 offsetof(struct bpf_sock_ops_kern, \ 6484 temp)); \ 6485 } while (0) 6486 6487 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE) \ 6488 do { \ 6489 if (TYPE == BPF_WRITE) \ 6490 SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \ 6491 else \ 6492 SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \ 6493 } while (0) 6494 6495 case offsetof(struct bpf_sock_ops, snd_cwnd): 6496 SOCK_OPS_GET_FIELD(snd_cwnd, snd_cwnd, struct tcp_sock); 6497 break; 6498 6499 case offsetof(struct bpf_sock_ops, srtt_us): 6500 SOCK_OPS_GET_FIELD(srtt_us, srtt_us, struct tcp_sock); 6501 break; 6502 6503 case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags): 6504 SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags, 6505 struct tcp_sock); 6506 break; 6507 6508 case offsetof(struct bpf_sock_ops, snd_ssthresh): 6509 SOCK_OPS_GET_FIELD(snd_ssthresh, snd_ssthresh, struct tcp_sock); 6510 break; 6511 6512 case offsetof(struct bpf_sock_ops, rcv_nxt): 6513 SOCK_OPS_GET_FIELD(rcv_nxt, rcv_nxt, struct tcp_sock); 6514 break; 6515 6516 case offsetof(struct bpf_sock_ops, snd_nxt): 6517 SOCK_OPS_GET_FIELD(snd_nxt, snd_nxt, struct tcp_sock); 6518 break; 6519 6520 case offsetof(struct bpf_sock_ops, snd_una): 6521 SOCK_OPS_GET_FIELD(snd_una, snd_una, struct tcp_sock); 6522 break; 6523 6524 case offsetof(struct bpf_sock_ops, mss_cache): 6525 SOCK_OPS_GET_FIELD(mss_cache, mss_cache, struct tcp_sock); 6526 break; 6527 6528 case offsetof(struct bpf_sock_ops, ecn_flags): 6529 SOCK_OPS_GET_FIELD(ecn_flags, ecn_flags, struct tcp_sock); 6530 break; 6531 6532 case offsetof(struct bpf_sock_ops, rate_delivered): 6533 SOCK_OPS_GET_FIELD(rate_delivered, rate_delivered, 6534 struct tcp_sock); 6535 break; 6536 6537 case offsetof(struct bpf_sock_ops, rate_interval_us): 6538 SOCK_OPS_GET_FIELD(rate_interval_us, rate_interval_us, 6539 struct tcp_sock); 6540 break; 6541 6542 case offsetof(struct bpf_sock_ops, packets_out): 6543 SOCK_OPS_GET_FIELD(packets_out, packets_out, struct tcp_sock); 6544 break; 6545 6546 case offsetof(struct bpf_sock_ops, retrans_out): 6547 SOCK_OPS_GET_FIELD(retrans_out, retrans_out, struct tcp_sock); 6548 break; 6549 6550 case offsetof(struct bpf_sock_ops, total_retrans): 6551 SOCK_OPS_GET_FIELD(total_retrans, total_retrans, 6552 struct tcp_sock); 6553 break; 6554 6555 case offsetof(struct bpf_sock_ops, segs_in): 6556 SOCK_OPS_GET_FIELD(segs_in, segs_in, struct tcp_sock); 6557 break; 6558 6559 case offsetof(struct bpf_sock_ops, data_segs_in): 6560 SOCK_OPS_GET_FIELD(data_segs_in, data_segs_in, struct tcp_sock); 6561 break; 6562 6563 case offsetof(struct bpf_sock_ops, segs_out): 6564 SOCK_OPS_GET_FIELD(segs_out, segs_out, struct tcp_sock); 6565 break; 6566 6567 case offsetof(struct bpf_sock_ops, data_segs_out): 6568 SOCK_OPS_GET_FIELD(data_segs_out, data_segs_out, 6569 struct tcp_sock); 6570 break; 6571 6572 case offsetof(struct bpf_sock_ops, lost_out): 6573 SOCK_OPS_GET_FIELD(lost_out, lost_out, struct tcp_sock); 6574 break; 6575 6576 case offsetof(struct bpf_sock_ops, sacked_out): 6577 SOCK_OPS_GET_FIELD(sacked_out, sacked_out, struct tcp_sock); 6578 break; 6579 6580 case offsetof(struct bpf_sock_ops, sk_txhash): 6581 SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash, 6582 struct sock, type); 6583 break; 6584 6585 case offsetof(struct bpf_sock_ops, bytes_received): 6586 SOCK_OPS_GET_FIELD(bytes_received, bytes_received, 6587 struct tcp_sock); 6588 break; 6589 6590 case offsetof(struct bpf_sock_ops, bytes_acked): 6591 SOCK_OPS_GET_FIELD(bytes_acked, bytes_acked, struct tcp_sock); 6592 break; 6593 6594 } 6595 return insn - insn_buf; 6596 } 6597 6598 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type, 6599 const struct bpf_insn *si, 6600 struct bpf_insn *insn_buf, 6601 struct bpf_prog *prog, u32 *target_size) 6602 { 6603 struct bpf_insn *insn = insn_buf; 6604 int off; 6605 6606 switch (si->off) { 6607 case offsetof(struct __sk_buff, data_end): 6608 off = si->off; 6609 off -= offsetof(struct __sk_buff, data_end); 6610 off += offsetof(struct sk_buff, cb); 6611 off += offsetof(struct tcp_skb_cb, bpf.data_end); 6612 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 6613 si->src_reg, off); 6614 break; 6615 default: 6616 return bpf_convert_ctx_access(type, si, insn_buf, prog, 6617 target_size); 6618 } 6619 6620 return insn - insn_buf; 6621 } 6622 6623 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type, 6624 const struct bpf_insn *si, 6625 struct bpf_insn *insn_buf, 6626 struct bpf_prog *prog, u32 *target_size) 6627 { 6628 struct bpf_insn *insn = insn_buf; 6629 #if IS_ENABLED(CONFIG_IPV6) 6630 int off; 6631 #endif 6632 6633 switch (si->off) { 6634 case offsetof(struct sk_msg_md, data): 6635 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data), 6636 si->dst_reg, si->src_reg, 6637 offsetof(struct sk_msg_buff, data)); 6638 break; 6639 case offsetof(struct sk_msg_md, data_end): 6640 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data_end), 6641 si->dst_reg, si->src_reg, 6642 offsetof(struct sk_msg_buff, data_end)); 6643 break; 6644 case offsetof(struct sk_msg_md, family): 6645 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 6646 6647 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6648 struct sk_msg_buff, sk), 6649 si->dst_reg, si->src_reg, 6650 offsetof(struct sk_msg_buff, sk)); 6651 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6652 offsetof(struct sock_common, skc_family)); 6653 break; 6654 6655 case offsetof(struct sk_msg_md, remote_ip4): 6656 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 6657 6658 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6659 struct sk_msg_buff, sk), 6660 si->dst_reg, si->src_reg, 6661 offsetof(struct sk_msg_buff, sk)); 6662 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6663 offsetof(struct sock_common, skc_daddr)); 6664 break; 6665 6666 case offsetof(struct sk_msg_md, local_ip4): 6667 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6668 skc_rcv_saddr) != 4); 6669 6670 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6671 struct sk_msg_buff, sk), 6672 si->dst_reg, si->src_reg, 6673 offsetof(struct sk_msg_buff, sk)); 6674 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6675 offsetof(struct sock_common, 6676 skc_rcv_saddr)); 6677 break; 6678 6679 case offsetof(struct sk_msg_md, remote_ip6[0]) ... 6680 offsetof(struct sk_msg_md, remote_ip6[3]): 6681 #if IS_ENABLED(CONFIG_IPV6) 6682 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6683 skc_v6_daddr.s6_addr32[0]) != 4); 6684 6685 off = si->off; 6686 off -= offsetof(struct sk_msg_md, remote_ip6[0]); 6687 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6688 struct sk_msg_buff, sk), 6689 si->dst_reg, si->src_reg, 6690 offsetof(struct sk_msg_buff, sk)); 6691 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6692 offsetof(struct sock_common, 6693 skc_v6_daddr.s6_addr32[0]) + 6694 off); 6695 #else 6696 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6697 #endif 6698 break; 6699 6700 case offsetof(struct sk_msg_md, local_ip6[0]) ... 6701 offsetof(struct sk_msg_md, local_ip6[3]): 6702 #if IS_ENABLED(CONFIG_IPV6) 6703 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6704 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 6705 6706 off = si->off; 6707 off -= offsetof(struct sk_msg_md, local_ip6[0]); 6708 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6709 struct sk_msg_buff, sk), 6710 si->dst_reg, si->src_reg, 6711 offsetof(struct sk_msg_buff, sk)); 6712 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6713 offsetof(struct sock_common, 6714 skc_v6_rcv_saddr.s6_addr32[0]) + 6715 off); 6716 #else 6717 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6718 #endif 6719 break; 6720 6721 case offsetof(struct sk_msg_md, remote_port): 6722 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 6723 6724 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6725 struct sk_msg_buff, sk), 6726 si->dst_reg, si->src_reg, 6727 offsetof(struct sk_msg_buff, sk)); 6728 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6729 offsetof(struct sock_common, skc_dport)); 6730 #ifndef __BIG_ENDIAN_BITFIELD 6731 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 6732 #endif 6733 break; 6734 6735 case offsetof(struct sk_msg_md, local_port): 6736 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 6737 6738 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6739 struct sk_msg_buff, sk), 6740 si->dst_reg, si->src_reg, 6741 offsetof(struct sk_msg_buff, sk)); 6742 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6743 offsetof(struct sock_common, skc_num)); 6744 break; 6745 } 6746 6747 return insn - insn_buf; 6748 } 6749 6750 const struct bpf_verifier_ops sk_filter_verifier_ops = { 6751 .get_func_proto = sk_filter_func_proto, 6752 .is_valid_access = sk_filter_is_valid_access, 6753 .convert_ctx_access = bpf_convert_ctx_access, 6754 .gen_ld_abs = bpf_gen_ld_abs, 6755 }; 6756 6757 const struct bpf_prog_ops sk_filter_prog_ops = { 6758 .test_run = bpf_prog_test_run_skb, 6759 }; 6760 6761 const struct bpf_verifier_ops tc_cls_act_verifier_ops = { 6762 .get_func_proto = tc_cls_act_func_proto, 6763 .is_valid_access = tc_cls_act_is_valid_access, 6764 .convert_ctx_access = tc_cls_act_convert_ctx_access, 6765 .gen_prologue = tc_cls_act_prologue, 6766 .gen_ld_abs = bpf_gen_ld_abs, 6767 }; 6768 6769 const struct bpf_prog_ops tc_cls_act_prog_ops = { 6770 .test_run = bpf_prog_test_run_skb, 6771 }; 6772 6773 const struct bpf_verifier_ops xdp_verifier_ops = { 6774 .get_func_proto = xdp_func_proto, 6775 .is_valid_access = xdp_is_valid_access, 6776 .convert_ctx_access = xdp_convert_ctx_access, 6777 }; 6778 6779 const struct bpf_prog_ops xdp_prog_ops = { 6780 .test_run = bpf_prog_test_run_xdp, 6781 }; 6782 6783 const struct bpf_verifier_ops cg_skb_verifier_ops = { 6784 .get_func_proto = sk_filter_func_proto, 6785 .is_valid_access = sk_filter_is_valid_access, 6786 .convert_ctx_access = bpf_convert_ctx_access, 6787 }; 6788 6789 const struct bpf_prog_ops cg_skb_prog_ops = { 6790 .test_run = bpf_prog_test_run_skb, 6791 }; 6792 6793 const struct bpf_verifier_ops lwt_in_verifier_ops = { 6794 .get_func_proto = lwt_in_func_proto, 6795 .is_valid_access = lwt_is_valid_access, 6796 .convert_ctx_access = bpf_convert_ctx_access, 6797 }; 6798 6799 const struct bpf_prog_ops lwt_in_prog_ops = { 6800 .test_run = bpf_prog_test_run_skb, 6801 }; 6802 6803 const struct bpf_verifier_ops lwt_out_verifier_ops = { 6804 .get_func_proto = lwt_out_func_proto, 6805 .is_valid_access = lwt_is_valid_access, 6806 .convert_ctx_access = bpf_convert_ctx_access, 6807 }; 6808 6809 const struct bpf_prog_ops lwt_out_prog_ops = { 6810 .test_run = bpf_prog_test_run_skb, 6811 }; 6812 6813 const struct bpf_verifier_ops lwt_xmit_verifier_ops = { 6814 .get_func_proto = lwt_xmit_func_proto, 6815 .is_valid_access = lwt_is_valid_access, 6816 .convert_ctx_access = bpf_convert_ctx_access, 6817 .gen_prologue = tc_cls_act_prologue, 6818 }; 6819 6820 const struct bpf_prog_ops lwt_xmit_prog_ops = { 6821 .test_run = bpf_prog_test_run_skb, 6822 }; 6823 6824 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = { 6825 .get_func_proto = lwt_seg6local_func_proto, 6826 .is_valid_access = lwt_is_valid_access, 6827 .convert_ctx_access = bpf_convert_ctx_access, 6828 }; 6829 6830 const struct bpf_prog_ops lwt_seg6local_prog_ops = { 6831 .test_run = bpf_prog_test_run_skb, 6832 }; 6833 6834 const struct bpf_verifier_ops cg_sock_verifier_ops = { 6835 .get_func_proto = sock_filter_func_proto, 6836 .is_valid_access = sock_filter_is_valid_access, 6837 .convert_ctx_access = sock_filter_convert_ctx_access, 6838 }; 6839 6840 const struct bpf_prog_ops cg_sock_prog_ops = { 6841 }; 6842 6843 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = { 6844 .get_func_proto = sock_addr_func_proto, 6845 .is_valid_access = sock_addr_is_valid_access, 6846 .convert_ctx_access = sock_addr_convert_ctx_access, 6847 }; 6848 6849 const struct bpf_prog_ops cg_sock_addr_prog_ops = { 6850 }; 6851 6852 const struct bpf_verifier_ops sock_ops_verifier_ops = { 6853 .get_func_proto = sock_ops_func_proto, 6854 .is_valid_access = sock_ops_is_valid_access, 6855 .convert_ctx_access = sock_ops_convert_ctx_access, 6856 }; 6857 6858 const struct bpf_prog_ops sock_ops_prog_ops = { 6859 }; 6860 6861 const struct bpf_verifier_ops sk_skb_verifier_ops = { 6862 .get_func_proto = sk_skb_func_proto, 6863 .is_valid_access = sk_skb_is_valid_access, 6864 .convert_ctx_access = sk_skb_convert_ctx_access, 6865 .gen_prologue = sk_skb_prologue, 6866 }; 6867 6868 const struct bpf_prog_ops sk_skb_prog_ops = { 6869 }; 6870 6871 const struct bpf_verifier_ops sk_msg_verifier_ops = { 6872 .get_func_proto = sk_msg_func_proto, 6873 .is_valid_access = sk_msg_is_valid_access, 6874 .convert_ctx_access = sk_msg_convert_ctx_access, 6875 }; 6876 6877 const struct bpf_prog_ops sk_msg_prog_ops = { 6878 }; 6879 6880 int sk_detach_filter(struct sock *sk) 6881 { 6882 int ret = -ENOENT; 6883 struct sk_filter *filter; 6884 6885 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 6886 return -EPERM; 6887 6888 filter = rcu_dereference_protected(sk->sk_filter, 6889 lockdep_sock_is_held(sk)); 6890 if (filter) { 6891 RCU_INIT_POINTER(sk->sk_filter, NULL); 6892 sk_filter_uncharge(sk, filter); 6893 ret = 0; 6894 } 6895 6896 return ret; 6897 } 6898 EXPORT_SYMBOL_GPL(sk_detach_filter); 6899 6900 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf, 6901 unsigned int len) 6902 { 6903 struct sock_fprog_kern *fprog; 6904 struct sk_filter *filter; 6905 int ret = 0; 6906 6907 lock_sock(sk); 6908 filter = rcu_dereference_protected(sk->sk_filter, 6909 lockdep_sock_is_held(sk)); 6910 if (!filter) 6911 goto out; 6912 6913 /* We're copying the filter that has been originally attached, 6914 * so no conversion/decode needed anymore. eBPF programs that 6915 * have no original program cannot be dumped through this. 6916 */ 6917 ret = -EACCES; 6918 fprog = filter->prog->orig_prog; 6919 if (!fprog) 6920 goto out; 6921 6922 ret = fprog->len; 6923 if (!len) 6924 /* User space only enquires number of filter blocks. */ 6925 goto out; 6926 6927 ret = -EINVAL; 6928 if (len < fprog->len) 6929 goto out; 6930 6931 ret = -EFAULT; 6932 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog))) 6933 goto out; 6934 6935 /* Instead of bytes, the API requests to return the number 6936 * of filter blocks. 6937 */ 6938 ret = fprog->len; 6939 out: 6940 release_sock(sk); 6941 return ret; 6942 } 6943