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 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H); 463 *insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset); 464 *insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP, size, 2 + endian); 465 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A, BPF_REG_D, 466 offset); 467 if (endian) 468 *insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8); 469 *insn++ = BPF_JMP_A(8); 470 } 471 472 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX); 473 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D); 474 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H); 475 if (!indirect) { 476 *insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset); 477 } else { 478 *insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X); 479 if (fp->k) 480 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset); 481 } 482 483 switch (BPF_SIZE(fp->code)) { 484 case BPF_B: 485 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8); 486 break; 487 case BPF_H: 488 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16); 489 break; 490 case BPF_W: 491 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32); 492 break; 493 default: 494 return false; 495 } 496 497 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2); 498 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 499 *insn = BPF_EXIT_INSN(); 500 501 *insnp = insn; 502 return true; 503 } 504 505 /** 506 * bpf_convert_filter - convert filter program 507 * @prog: the user passed filter program 508 * @len: the length of the user passed filter program 509 * @new_prog: allocated 'struct bpf_prog' or NULL 510 * @new_len: pointer to store length of converted program 511 * @seen_ld_abs: bool whether we've seen ld_abs/ind 512 * 513 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn' 514 * style extended BPF (eBPF). 515 * Conversion workflow: 516 * 517 * 1) First pass for calculating the new program length: 518 * bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs) 519 * 520 * 2) 2nd pass to remap in two passes: 1st pass finds new 521 * jump offsets, 2nd pass remapping: 522 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs) 523 */ 524 static int bpf_convert_filter(struct sock_filter *prog, int len, 525 struct bpf_prog *new_prog, int *new_len, 526 bool *seen_ld_abs) 527 { 528 int new_flen = 0, pass = 0, target, i, stack_off; 529 struct bpf_insn *new_insn, *first_insn = NULL; 530 struct sock_filter *fp; 531 int *addrs = NULL; 532 u8 bpf_src; 533 534 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK); 535 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG); 536 537 if (len <= 0 || len > BPF_MAXINSNS) 538 return -EINVAL; 539 540 if (new_prog) { 541 first_insn = new_prog->insnsi; 542 addrs = kcalloc(len, sizeof(*addrs), 543 GFP_KERNEL | __GFP_NOWARN); 544 if (!addrs) 545 return -ENOMEM; 546 } 547 548 do_pass: 549 new_insn = first_insn; 550 fp = prog; 551 552 /* Classic BPF related prologue emission. */ 553 if (new_prog) { 554 /* Classic BPF expects A and X to be reset first. These need 555 * to be guaranteed to be the first two instructions. 556 */ 557 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 558 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X); 559 560 /* All programs must keep CTX in callee saved BPF_REG_CTX. 561 * In eBPF case it's done by the compiler, here we need to 562 * do this ourself. Initial CTX is present in BPF_REG_ARG1. 563 */ 564 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1); 565 if (*seen_ld_abs) { 566 /* For packet access in classic BPF, cache skb->data 567 * in callee-saved BPF R8 and skb->len - skb->data_len 568 * (headlen) in BPF R9. Since classic BPF is read-only 569 * on CTX, we only need to cache it once. 570 */ 571 *new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data), 572 BPF_REG_D, BPF_REG_CTX, 573 offsetof(struct sk_buff, data)); 574 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX, 575 offsetof(struct sk_buff, len)); 576 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX, 577 offsetof(struct sk_buff, data_len)); 578 *new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP); 579 } 580 } else { 581 new_insn += 3; 582 } 583 584 for (i = 0; i < len; fp++, i++) { 585 struct bpf_insn tmp_insns[32] = { }; 586 struct bpf_insn *insn = tmp_insns; 587 588 if (addrs) 589 addrs[i] = new_insn - first_insn; 590 591 switch (fp->code) { 592 /* All arithmetic insns and skb loads map as-is. */ 593 case BPF_ALU | BPF_ADD | BPF_X: 594 case BPF_ALU | BPF_ADD | BPF_K: 595 case BPF_ALU | BPF_SUB | BPF_X: 596 case BPF_ALU | BPF_SUB | BPF_K: 597 case BPF_ALU | BPF_AND | BPF_X: 598 case BPF_ALU | BPF_AND | BPF_K: 599 case BPF_ALU | BPF_OR | BPF_X: 600 case BPF_ALU | BPF_OR | BPF_K: 601 case BPF_ALU | BPF_LSH | BPF_X: 602 case BPF_ALU | BPF_LSH | BPF_K: 603 case BPF_ALU | BPF_RSH | BPF_X: 604 case BPF_ALU | BPF_RSH | BPF_K: 605 case BPF_ALU | BPF_XOR | BPF_X: 606 case BPF_ALU | BPF_XOR | BPF_K: 607 case BPF_ALU | BPF_MUL | BPF_X: 608 case BPF_ALU | BPF_MUL | BPF_K: 609 case BPF_ALU | BPF_DIV | BPF_X: 610 case BPF_ALU | BPF_DIV | BPF_K: 611 case BPF_ALU | BPF_MOD | BPF_X: 612 case BPF_ALU | BPF_MOD | BPF_K: 613 case BPF_ALU | BPF_NEG: 614 case BPF_LD | BPF_ABS | BPF_W: 615 case BPF_LD | BPF_ABS | BPF_H: 616 case BPF_LD | BPF_ABS | BPF_B: 617 case BPF_LD | BPF_IND | BPF_W: 618 case BPF_LD | BPF_IND | BPF_H: 619 case BPF_LD | BPF_IND | BPF_B: 620 /* Check for overloaded BPF extension and 621 * directly convert it if found, otherwise 622 * just move on with mapping. 623 */ 624 if (BPF_CLASS(fp->code) == BPF_LD && 625 BPF_MODE(fp->code) == BPF_ABS && 626 convert_bpf_extensions(fp, &insn)) 627 break; 628 if (BPF_CLASS(fp->code) == BPF_LD && 629 convert_bpf_ld_abs(fp, &insn)) { 630 *seen_ld_abs = true; 631 break; 632 } 633 634 if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) || 635 fp->code == (BPF_ALU | BPF_MOD | BPF_X)) { 636 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X); 637 /* Error with exception code on div/mod by 0. 638 * For cBPF programs, this was always return 0. 639 */ 640 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2); 641 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); 642 *insn++ = BPF_EXIT_INSN(); 643 } 644 645 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k); 646 break; 647 648 /* Jump transformation cannot use BPF block macros 649 * everywhere as offset calculation and target updates 650 * require a bit more work than the rest, i.e. jump 651 * opcodes map as-is, but offsets need adjustment. 652 */ 653 654 #define BPF_EMIT_JMP \ 655 do { \ 656 const s32 off_min = S16_MIN, off_max = S16_MAX; \ 657 s32 off; \ 658 \ 659 if (target >= len || target < 0) \ 660 goto err; \ 661 off = addrs ? addrs[target] - addrs[i] - 1 : 0; \ 662 /* Adjust pc relative offset for 2nd or 3rd insn. */ \ 663 off -= insn - tmp_insns; \ 664 /* Reject anything not fitting into insn->off. */ \ 665 if (off < off_min || off > off_max) \ 666 goto err; \ 667 insn->off = off; \ 668 } while (0) 669 670 case BPF_JMP | BPF_JA: 671 target = i + fp->k + 1; 672 insn->code = fp->code; 673 BPF_EMIT_JMP; 674 break; 675 676 case BPF_JMP | BPF_JEQ | BPF_K: 677 case BPF_JMP | BPF_JEQ | BPF_X: 678 case BPF_JMP | BPF_JSET | BPF_K: 679 case BPF_JMP | BPF_JSET | BPF_X: 680 case BPF_JMP | BPF_JGT | BPF_K: 681 case BPF_JMP | BPF_JGT | BPF_X: 682 case BPF_JMP | BPF_JGE | BPF_K: 683 case BPF_JMP | BPF_JGE | BPF_X: 684 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) { 685 /* BPF immediates are signed, zero extend 686 * immediate into tmp register and use it 687 * in compare insn. 688 */ 689 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k); 690 691 insn->dst_reg = BPF_REG_A; 692 insn->src_reg = BPF_REG_TMP; 693 bpf_src = BPF_X; 694 } else { 695 insn->dst_reg = BPF_REG_A; 696 insn->imm = fp->k; 697 bpf_src = BPF_SRC(fp->code); 698 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0; 699 } 700 701 /* Common case where 'jump_false' is next insn. */ 702 if (fp->jf == 0) { 703 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; 704 target = i + fp->jt + 1; 705 BPF_EMIT_JMP; 706 break; 707 } 708 709 /* Convert some jumps when 'jump_true' is next insn. */ 710 if (fp->jt == 0) { 711 switch (BPF_OP(fp->code)) { 712 case BPF_JEQ: 713 insn->code = BPF_JMP | BPF_JNE | bpf_src; 714 break; 715 case BPF_JGT: 716 insn->code = BPF_JMP | BPF_JLE | bpf_src; 717 break; 718 case BPF_JGE: 719 insn->code = BPF_JMP | BPF_JLT | bpf_src; 720 break; 721 default: 722 goto jmp_rest; 723 } 724 725 target = i + fp->jf + 1; 726 BPF_EMIT_JMP; 727 break; 728 } 729 jmp_rest: 730 /* Other jumps are mapped into two insns: Jxx and JA. */ 731 target = i + fp->jt + 1; 732 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; 733 BPF_EMIT_JMP; 734 insn++; 735 736 insn->code = BPF_JMP | BPF_JA; 737 target = i + fp->jf + 1; 738 BPF_EMIT_JMP; 739 break; 740 741 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */ 742 case BPF_LDX | BPF_MSH | BPF_B: { 743 struct sock_filter tmp = { 744 .code = BPF_LD | BPF_ABS | BPF_B, 745 .k = fp->k, 746 }; 747 748 *seen_ld_abs = true; 749 750 /* X = A */ 751 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 752 /* A = BPF_R0 = *(u8 *) (skb->data + K) */ 753 convert_bpf_ld_abs(&tmp, &insn); 754 insn++; 755 /* A &= 0xf */ 756 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf); 757 /* A <<= 2 */ 758 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2); 759 /* tmp = X */ 760 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X); 761 /* X = A */ 762 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 763 /* A = tmp */ 764 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP); 765 break; 766 } 767 /* RET_K is remaped into 2 insns. RET_A case doesn't need an 768 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A. 769 */ 770 case BPF_RET | BPF_A: 771 case BPF_RET | BPF_K: 772 if (BPF_RVAL(fp->code) == BPF_K) 773 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0, 774 0, fp->k); 775 *insn = BPF_EXIT_INSN(); 776 break; 777 778 /* Store to stack. */ 779 case BPF_ST: 780 case BPF_STX: 781 stack_off = fp->k * 4 + 4; 782 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) == 783 BPF_ST ? BPF_REG_A : BPF_REG_X, 784 -stack_off); 785 /* check_load_and_stores() verifies that classic BPF can 786 * load from stack only after write, so tracking 787 * stack_depth for ST|STX insns is enough 788 */ 789 if (new_prog && new_prog->aux->stack_depth < stack_off) 790 new_prog->aux->stack_depth = stack_off; 791 break; 792 793 /* Load from stack. */ 794 case BPF_LD | BPF_MEM: 795 case BPF_LDX | BPF_MEM: 796 stack_off = fp->k * 4 + 4; 797 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? 798 BPF_REG_A : BPF_REG_X, BPF_REG_FP, 799 -stack_off); 800 break; 801 802 /* A = K or X = K */ 803 case BPF_LD | BPF_IMM: 804 case BPF_LDX | BPF_IMM: 805 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ? 806 BPF_REG_A : BPF_REG_X, fp->k); 807 break; 808 809 /* X = A */ 810 case BPF_MISC | BPF_TAX: 811 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); 812 break; 813 814 /* A = X */ 815 case BPF_MISC | BPF_TXA: 816 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X); 817 break; 818 819 /* A = skb->len or X = skb->len */ 820 case BPF_LD | BPF_W | BPF_LEN: 821 case BPF_LDX | BPF_W | BPF_LEN: 822 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? 823 BPF_REG_A : BPF_REG_X, BPF_REG_CTX, 824 offsetof(struct sk_buff, len)); 825 break; 826 827 /* Access seccomp_data fields. */ 828 case BPF_LDX | BPF_ABS | BPF_W: 829 /* A = *(u32 *) (ctx + K) */ 830 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k); 831 break; 832 833 /* Unknown instruction. */ 834 default: 835 goto err; 836 } 837 838 insn++; 839 if (new_prog) 840 memcpy(new_insn, tmp_insns, 841 sizeof(*insn) * (insn - tmp_insns)); 842 new_insn += insn - tmp_insns; 843 } 844 845 if (!new_prog) { 846 /* Only calculating new length. */ 847 *new_len = new_insn - first_insn; 848 if (*seen_ld_abs) 849 *new_len += 4; /* Prologue bits. */ 850 return 0; 851 } 852 853 pass++; 854 if (new_flen != new_insn - first_insn) { 855 new_flen = new_insn - first_insn; 856 if (pass > 2) 857 goto err; 858 goto do_pass; 859 } 860 861 kfree(addrs); 862 BUG_ON(*new_len != new_flen); 863 return 0; 864 err: 865 kfree(addrs); 866 return -EINVAL; 867 } 868 869 /* Security: 870 * 871 * As we dont want to clear mem[] array for each packet going through 872 * __bpf_prog_run(), we check that filter loaded by user never try to read 873 * a cell if not previously written, and we check all branches to be sure 874 * a malicious user doesn't try to abuse us. 875 */ 876 static int check_load_and_stores(const struct sock_filter *filter, int flen) 877 { 878 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */ 879 int pc, ret = 0; 880 881 BUILD_BUG_ON(BPF_MEMWORDS > 16); 882 883 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL); 884 if (!masks) 885 return -ENOMEM; 886 887 memset(masks, 0xff, flen * sizeof(*masks)); 888 889 for (pc = 0; pc < flen; pc++) { 890 memvalid &= masks[pc]; 891 892 switch (filter[pc].code) { 893 case BPF_ST: 894 case BPF_STX: 895 memvalid |= (1 << filter[pc].k); 896 break; 897 case BPF_LD | BPF_MEM: 898 case BPF_LDX | BPF_MEM: 899 if (!(memvalid & (1 << filter[pc].k))) { 900 ret = -EINVAL; 901 goto error; 902 } 903 break; 904 case BPF_JMP | BPF_JA: 905 /* A jump must set masks on target */ 906 masks[pc + 1 + filter[pc].k] &= memvalid; 907 memvalid = ~0; 908 break; 909 case BPF_JMP | BPF_JEQ | BPF_K: 910 case BPF_JMP | BPF_JEQ | BPF_X: 911 case BPF_JMP | BPF_JGE | BPF_K: 912 case BPF_JMP | BPF_JGE | BPF_X: 913 case BPF_JMP | BPF_JGT | BPF_K: 914 case BPF_JMP | BPF_JGT | BPF_X: 915 case BPF_JMP | BPF_JSET | BPF_K: 916 case BPF_JMP | BPF_JSET | BPF_X: 917 /* A jump must set masks on targets */ 918 masks[pc + 1 + filter[pc].jt] &= memvalid; 919 masks[pc + 1 + filter[pc].jf] &= memvalid; 920 memvalid = ~0; 921 break; 922 } 923 } 924 error: 925 kfree(masks); 926 return ret; 927 } 928 929 static bool chk_code_allowed(u16 code_to_probe) 930 { 931 static const bool codes[] = { 932 /* 32 bit ALU operations */ 933 [BPF_ALU | BPF_ADD | BPF_K] = true, 934 [BPF_ALU | BPF_ADD | BPF_X] = true, 935 [BPF_ALU | BPF_SUB | BPF_K] = true, 936 [BPF_ALU | BPF_SUB | BPF_X] = true, 937 [BPF_ALU | BPF_MUL | BPF_K] = true, 938 [BPF_ALU | BPF_MUL | BPF_X] = true, 939 [BPF_ALU | BPF_DIV | BPF_K] = true, 940 [BPF_ALU | BPF_DIV | BPF_X] = true, 941 [BPF_ALU | BPF_MOD | BPF_K] = true, 942 [BPF_ALU | BPF_MOD | BPF_X] = true, 943 [BPF_ALU | BPF_AND | BPF_K] = true, 944 [BPF_ALU | BPF_AND | BPF_X] = true, 945 [BPF_ALU | BPF_OR | BPF_K] = true, 946 [BPF_ALU | BPF_OR | BPF_X] = true, 947 [BPF_ALU | BPF_XOR | BPF_K] = true, 948 [BPF_ALU | BPF_XOR | BPF_X] = true, 949 [BPF_ALU | BPF_LSH | BPF_K] = true, 950 [BPF_ALU | BPF_LSH | BPF_X] = true, 951 [BPF_ALU | BPF_RSH | BPF_K] = true, 952 [BPF_ALU | BPF_RSH | BPF_X] = true, 953 [BPF_ALU | BPF_NEG] = true, 954 /* Load instructions */ 955 [BPF_LD | BPF_W | BPF_ABS] = true, 956 [BPF_LD | BPF_H | BPF_ABS] = true, 957 [BPF_LD | BPF_B | BPF_ABS] = true, 958 [BPF_LD | BPF_W | BPF_LEN] = true, 959 [BPF_LD | BPF_W | BPF_IND] = true, 960 [BPF_LD | BPF_H | BPF_IND] = true, 961 [BPF_LD | BPF_B | BPF_IND] = true, 962 [BPF_LD | BPF_IMM] = true, 963 [BPF_LD | BPF_MEM] = true, 964 [BPF_LDX | BPF_W | BPF_LEN] = true, 965 [BPF_LDX | BPF_B | BPF_MSH] = true, 966 [BPF_LDX | BPF_IMM] = true, 967 [BPF_LDX | BPF_MEM] = true, 968 /* Store instructions */ 969 [BPF_ST] = true, 970 [BPF_STX] = true, 971 /* Misc instructions */ 972 [BPF_MISC | BPF_TAX] = true, 973 [BPF_MISC | BPF_TXA] = true, 974 /* Return instructions */ 975 [BPF_RET | BPF_K] = true, 976 [BPF_RET | BPF_A] = true, 977 /* Jump instructions */ 978 [BPF_JMP | BPF_JA] = true, 979 [BPF_JMP | BPF_JEQ | BPF_K] = true, 980 [BPF_JMP | BPF_JEQ | BPF_X] = true, 981 [BPF_JMP | BPF_JGE | BPF_K] = true, 982 [BPF_JMP | BPF_JGE | BPF_X] = true, 983 [BPF_JMP | BPF_JGT | BPF_K] = true, 984 [BPF_JMP | BPF_JGT | BPF_X] = true, 985 [BPF_JMP | BPF_JSET | BPF_K] = true, 986 [BPF_JMP | BPF_JSET | BPF_X] = true, 987 }; 988 989 if (code_to_probe >= ARRAY_SIZE(codes)) 990 return false; 991 992 return codes[code_to_probe]; 993 } 994 995 static bool bpf_check_basics_ok(const struct sock_filter *filter, 996 unsigned int flen) 997 { 998 if (filter == NULL) 999 return false; 1000 if (flen == 0 || flen > BPF_MAXINSNS) 1001 return false; 1002 1003 return true; 1004 } 1005 1006 /** 1007 * bpf_check_classic - verify socket filter code 1008 * @filter: filter to verify 1009 * @flen: length of filter 1010 * 1011 * Check the user's filter code. If we let some ugly 1012 * filter code slip through kaboom! The filter must contain 1013 * no references or jumps that are out of range, no illegal 1014 * instructions, and must end with a RET instruction. 1015 * 1016 * All jumps are forward as they are not signed. 1017 * 1018 * Returns 0 if the rule set is legal or -EINVAL if not. 1019 */ 1020 static int bpf_check_classic(const struct sock_filter *filter, 1021 unsigned int flen) 1022 { 1023 bool anc_found; 1024 int pc; 1025 1026 /* Check the filter code now */ 1027 for (pc = 0; pc < flen; pc++) { 1028 const struct sock_filter *ftest = &filter[pc]; 1029 1030 /* May we actually operate on this code? */ 1031 if (!chk_code_allowed(ftest->code)) 1032 return -EINVAL; 1033 1034 /* Some instructions need special checks */ 1035 switch (ftest->code) { 1036 case BPF_ALU | BPF_DIV | BPF_K: 1037 case BPF_ALU | BPF_MOD | BPF_K: 1038 /* Check for division by zero */ 1039 if (ftest->k == 0) 1040 return -EINVAL; 1041 break; 1042 case BPF_ALU | BPF_LSH | BPF_K: 1043 case BPF_ALU | BPF_RSH | BPF_K: 1044 if (ftest->k >= 32) 1045 return -EINVAL; 1046 break; 1047 case BPF_LD | BPF_MEM: 1048 case BPF_LDX | BPF_MEM: 1049 case BPF_ST: 1050 case BPF_STX: 1051 /* Check for invalid memory addresses */ 1052 if (ftest->k >= BPF_MEMWORDS) 1053 return -EINVAL; 1054 break; 1055 case BPF_JMP | BPF_JA: 1056 /* Note, the large ftest->k might cause loops. 1057 * Compare this with conditional jumps below, 1058 * where offsets are limited. --ANK (981016) 1059 */ 1060 if (ftest->k >= (unsigned int)(flen - pc - 1)) 1061 return -EINVAL; 1062 break; 1063 case BPF_JMP | BPF_JEQ | BPF_K: 1064 case BPF_JMP | BPF_JEQ | BPF_X: 1065 case BPF_JMP | BPF_JGE | BPF_K: 1066 case BPF_JMP | BPF_JGE | BPF_X: 1067 case BPF_JMP | BPF_JGT | BPF_K: 1068 case BPF_JMP | BPF_JGT | BPF_X: 1069 case BPF_JMP | BPF_JSET | BPF_K: 1070 case BPF_JMP | BPF_JSET | BPF_X: 1071 /* Both conditionals must be safe */ 1072 if (pc + ftest->jt + 1 >= flen || 1073 pc + ftest->jf + 1 >= flen) 1074 return -EINVAL; 1075 break; 1076 case BPF_LD | BPF_W | BPF_ABS: 1077 case BPF_LD | BPF_H | BPF_ABS: 1078 case BPF_LD | BPF_B | BPF_ABS: 1079 anc_found = false; 1080 if (bpf_anc_helper(ftest) & BPF_ANC) 1081 anc_found = true; 1082 /* Ancillary operation unknown or unsupported */ 1083 if (anc_found == false && ftest->k >= SKF_AD_OFF) 1084 return -EINVAL; 1085 } 1086 } 1087 1088 /* Last instruction must be a RET code */ 1089 switch (filter[flen - 1].code) { 1090 case BPF_RET | BPF_K: 1091 case BPF_RET | BPF_A: 1092 return check_load_and_stores(filter, flen); 1093 } 1094 1095 return -EINVAL; 1096 } 1097 1098 static int bpf_prog_store_orig_filter(struct bpf_prog *fp, 1099 const struct sock_fprog *fprog) 1100 { 1101 unsigned int fsize = bpf_classic_proglen(fprog); 1102 struct sock_fprog_kern *fkprog; 1103 1104 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL); 1105 if (!fp->orig_prog) 1106 return -ENOMEM; 1107 1108 fkprog = fp->orig_prog; 1109 fkprog->len = fprog->len; 1110 1111 fkprog->filter = kmemdup(fp->insns, fsize, 1112 GFP_KERNEL | __GFP_NOWARN); 1113 if (!fkprog->filter) { 1114 kfree(fp->orig_prog); 1115 return -ENOMEM; 1116 } 1117 1118 return 0; 1119 } 1120 1121 static void bpf_release_orig_filter(struct bpf_prog *fp) 1122 { 1123 struct sock_fprog_kern *fprog = fp->orig_prog; 1124 1125 if (fprog) { 1126 kfree(fprog->filter); 1127 kfree(fprog); 1128 } 1129 } 1130 1131 static void __bpf_prog_release(struct bpf_prog *prog) 1132 { 1133 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) { 1134 bpf_prog_put(prog); 1135 } else { 1136 bpf_release_orig_filter(prog); 1137 bpf_prog_free(prog); 1138 } 1139 } 1140 1141 static void __sk_filter_release(struct sk_filter *fp) 1142 { 1143 __bpf_prog_release(fp->prog); 1144 kfree(fp); 1145 } 1146 1147 /** 1148 * sk_filter_release_rcu - Release a socket filter by rcu_head 1149 * @rcu: rcu_head that contains the sk_filter to free 1150 */ 1151 static void sk_filter_release_rcu(struct rcu_head *rcu) 1152 { 1153 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu); 1154 1155 __sk_filter_release(fp); 1156 } 1157 1158 /** 1159 * sk_filter_release - release a socket filter 1160 * @fp: filter to remove 1161 * 1162 * Remove a filter from a socket and release its resources. 1163 */ 1164 static void sk_filter_release(struct sk_filter *fp) 1165 { 1166 if (refcount_dec_and_test(&fp->refcnt)) 1167 call_rcu(&fp->rcu, sk_filter_release_rcu); 1168 } 1169 1170 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) 1171 { 1172 u32 filter_size = bpf_prog_size(fp->prog->len); 1173 1174 atomic_sub(filter_size, &sk->sk_omem_alloc); 1175 sk_filter_release(fp); 1176 } 1177 1178 /* try to charge the socket memory if there is space available 1179 * return true on success 1180 */ 1181 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1182 { 1183 u32 filter_size = bpf_prog_size(fp->prog->len); 1184 1185 /* same check as in sock_kmalloc() */ 1186 if (filter_size <= sysctl_optmem_max && 1187 atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) { 1188 atomic_add(filter_size, &sk->sk_omem_alloc); 1189 return true; 1190 } 1191 return false; 1192 } 1193 1194 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1195 { 1196 if (!refcount_inc_not_zero(&fp->refcnt)) 1197 return false; 1198 1199 if (!__sk_filter_charge(sk, fp)) { 1200 sk_filter_release(fp); 1201 return false; 1202 } 1203 return true; 1204 } 1205 1206 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp) 1207 { 1208 struct sock_filter *old_prog; 1209 struct bpf_prog *old_fp; 1210 int err, new_len, old_len = fp->len; 1211 bool seen_ld_abs = false; 1212 1213 /* We are free to overwrite insns et al right here as it 1214 * won't be used at this point in time anymore internally 1215 * after the migration to the internal BPF instruction 1216 * representation. 1217 */ 1218 BUILD_BUG_ON(sizeof(struct sock_filter) != 1219 sizeof(struct bpf_insn)); 1220 1221 /* Conversion cannot happen on overlapping memory areas, 1222 * so we need to keep the user BPF around until the 2nd 1223 * pass. At this time, the user BPF is stored in fp->insns. 1224 */ 1225 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter), 1226 GFP_KERNEL | __GFP_NOWARN); 1227 if (!old_prog) { 1228 err = -ENOMEM; 1229 goto out_err; 1230 } 1231 1232 /* 1st pass: calculate the new program length. */ 1233 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len, 1234 &seen_ld_abs); 1235 if (err) 1236 goto out_err_free; 1237 1238 /* Expand fp for appending the new filter representation. */ 1239 old_fp = fp; 1240 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0); 1241 if (!fp) { 1242 /* The old_fp is still around in case we couldn't 1243 * allocate new memory, so uncharge on that one. 1244 */ 1245 fp = old_fp; 1246 err = -ENOMEM; 1247 goto out_err_free; 1248 } 1249 1250 fp->len = new_len; 1251 1252 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */ 1253 err = bpf_convert_filter(old_prog, old_len, fp, &new_len, 1254 &seen_ld_abs); 1255 if (err) 1256 /* 2nd bpf_convert_filter() can fail only if it fails 1257 * to allocate memory, remapping must succeed. Note, 1258 * that at this time old_fp has already been released 1259 * by krealloc(). 1260 */ 1261 goto out_err_free; 1262 1263 fp = bpf_prog_select_runtime(fp, &err); 1264 if (err) 1265 goto out_err_free; 1266 1267 kfree(old_prog); 1268 return fp; 1269 1270 out_err_free: 1271 kfree(old_prog); 1272 out_err: 1273 __bpf_prog_release(fp); 1274 return ERR_PTR(err); 1275 } 1276 1277 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp, 1278 bpf_aux_classic_check_t trans) 1279 { 1280 int err; 1281 1282 fp->bpf_func = NULL; 1283 fp->jited = 0; 1284 1285 err = bpf_check_classic(fp->insns, fp->len); 1286 if (err) { 1287 __bpf_prog_release(fp); 1288 return ERR_PTR(err); 1289 } 1290 1291 /* There might be additional checks and transformations 1292 * needed on classic filters, f.e. in case of seccomp. 1293 */ 1294 if (trans) { 1295 err = trans(fp->insns, fp->len); 1296 if (err) { 1297 __bpf_prog_release(fp); 1298 return ERR_PTR(err); 1299 } 1300 } 1301 1302 /* Probe if we can JIT compile the filter and if so, do 1303 * the compilation of the filter. 1304 */ 1305 bpf_jit_compile(fp); 1306 1307 /* JIT compiler couldn't process this filter, so do the 1308 * internal BPF translation for the optimized interpreter. 1309 */ 1310 if (!fp->jited) 1311 fp = bpf_migrate_filter(fp); 1312 1313 return fp; 1314 } 1315 1316 /** 1317 * bpf_prog_create - create an unattached filter 1318 * @pfp: the unattached filter that is created 1319 * @fprog: the filter program 1320 * 1321 * Create a filter independent of any socket. We first run some 1322 * sanity checks on it to make sure it does not explode on us later. 1323 * If an error occurs or there is insufficient memory for the filter 1324 * a negative errno code is returned. On success the return is zero. 1325 */ 1326 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog) 1327 { 1328 unsigned int fsize = bpf_classic_proglen(fprog); 1329 struct bpf_prog *fp; 1330 1331 /* Make sure new filter is there and in the right amounts. */ 1332 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1333 return -EINVAL; 1334 1335 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1336 if (!fp) 1337 return -ENOMEM; 1338 1339 memcpy(fp->insns, fprog->filter, fsize); 1340 1341 fp->len = fprog->len; 1342 /* Since unattached filters are not copied back to user 1343 * space through sk_get_filter(), we do not need to hold 1344 * a copy here, and can spare us the work. 1345 */ 1346 fp->orig_prog = NULL; 1347 1348 /* bpf_prepare_filter() already takes care of freeing 1349 * memory in case something goes wrong. 1350 */ 1351 fp = bpf_prepare_filter(fp, NULL); 1352 if (IS_ERR(fp)) 1353 return PTR_ERR(fp); 1354 1355 *pfp = fp; 1356 return 0; 1357 } 1358 EXPORT_SYMBOL_GPL(bpf_prog_create); 1359 1360 /** 1361 * bpf_prog_create_from_user - create an unattached filter from user buffer 1362 * @pfp: the unattached filter that is created 1363 * @fprog: the filter program 1364 * @trans: post-classic verifier transformation handler 1365 * @save_orig: save classic BPF program 1366 * 1367 * This function effectively does the same as bpf_prog_create(), only 1368 * that it builds up its insns buffer from user space provided buffer. 1369 * It also allows for passing a bpf_aux_classic_check_t handler. 1370 */ 1371 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, 1372 bpf_aux_classic_check_t trans, bool save_orig) 1373 { 1374 unsigned int fsize = bpf_classic_proglen(fprog); 1375 struct bpf_prog *fp; 1376 int err; 1377 1378 /* Make sure new filter is there and in the right amounts. */ 1379 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1380 return -EINVAL; 1381 1382 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1383 if (!fp) 1384 return -ENOMEM; 1385 1386 if (copy_from_user(fp->insns, fprog->filter, fsize)) { 1387 __bpf_prog_free(fp); 1388 return -EFAULT; 1389 } 1390 1391 fp->len = fprog->len; 1392 fp->orig_prog = NULL; 1393 1394 if (save_orig) { 1395 err = bpf_prog_store_orig_filter(fp, fprog); 1396 if (err) { 1397 __bpf_prog_free(fp); 1398 return -ENOMEM; 1399 } 1400 } 1401 1402 /* bpf_prepare_filter() already takes care of freeing 1403 * memory in case something goes wrong. 1404 */ 1405 fp = bpf_prepare_filter(fp, trans); 1406 if (IS_ERR(fp)) 1407 return PTR_ERR(fp); 1408 1409 *pfp = fp; 1410 return 0; 1411 } 1412 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user); 1413 1414 void bpf_prog_destroy(struct bpf_prog *fp) 1415 { 1416 __bpf_prog_release(fp); 1417 } 1418 EXPORT_SYMBOL_GPL(bpf_prog_destroy); 1419 1420 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk) 1421 { 1422 struct sk_filter *fp, *old_fp; 1423 1424 fp = kmalloc(sizeof(*fp), GFP_KERNEL); 1425 if (!fp) 1426 return -ENOMEM; 1427 1428 fp->prog = prog; 1429 1430 if (!__sk_filter_charge(sk, fp)) { 1431 kfree(fp); 1432 return -ENOMEM; 1433 } 1434 refcount_set(&fp->refcnt, 1); 1435 1436 old_fp = rcu_dereference_protected(sk->sk_filter, 1437 lockdep_sock_is_held(sk)); 1438 rcu_assign_pointer(sk->sk_filter, fp); 1439 1440 if (old_fp) 1441 sk_filter_uncharge(sk, old_fp); 1442 1443 return 0; 1444 } 1445 1446 static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk) 1447 { 1448 struct bpf_prog *old_prog; 1449 int err; 1450 1451 if (bpf_prog_size(prog->len) > sysctl_optmem_max) 1452 return -ENOMEM; 1453 1454 if (sk_unhashed(sk) && sk->sk_reuseport) { 1455 err = reuseport_alloc(sk); 1456 if (err) 1457 return err; 1458 } else if (!rcu_access_pointer(sk->sk_reuseport_cb)) { 1459 /* The socket wasn't bound with SO_REUSEPORT */ 1460 return -EINVAL; 1461 } 1462 1463 old_prog = reuseport_attach_prog(sk, prog); 1464 if (old_prog) 1465 bpf_prog_destroy(old_prog); 1466 1467 return 0; 1468 } 1469 1470 static 1471 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk) 1472 { 1473 unsigned int fsize = bpf_classic_proglen(fprog); 1474 struct bpf_prog *prog; 1475 int err; 1476 1477 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 1478 return ERR_PTR(-EPERM); 1479 1480 /* Make sure new filter is there and in the right amounts. */ 1481 if (!bpf_check_basics_ok(fprog->filter, fprog->len)) 1482 return ERR_PTR(-EINVAL); 1483 1484 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); 1485 if (!prog) 1486 return ERR_PTR(-ENOMEM); 1487 1488 if (copy_from_user(prog->insns, fprog->filter, fsize)) { 1489 __bpf_prog_free(prog); 1490 return ERR_PTR(-EFAULT); 1491 } 1492 1493 prog->len = fprog->len; 1494 1495 err = bpf_prog_store_orig_filter(prog, fprog); 1496 if (err) { 1497 __bpf_prog_free(prog); 1498 return ERR_PTR(-ENOMEM); 1499 } 1500 1501 /* bpf_prepare_filter() already takes care of freeing 1502 * memory in case something goes wrong. 1503 */ 1504 return bpf_prepare_filter(prog, NULL); 1505 } 1506 1507 /** 1508 * sk_attach_filter - attach a socket filter 1509 * @fprog: the filter program 1510 * @sk: the socket to use 1511 * 1512 * Attach the user's filter code. We first run some sanity checks on 1513 * it to make sure it does not explode on us later. If an error 1514 * occurs or there is insufficient memory for the filter a negative 1515 * errno code is returned. On success the return is zero. 1516 */ 1517 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk) 1518 { 1519 struct bpf_prog *prog = __get_filter(fprog, sk); 1520 int err; 1521 1522 if (IS_ERR(prog)) 1523 return PTR_ERR(prog); 1524 1525 err = __sk_attach_prog(prog, sk); 1526 if (err < 0) { 1527 __bpf_prog_release(prog); 1528 return err; 1529 } 1530 1531 return 0; 1532 } 1533 EXPORT_SYMBOL_GPL(sk_attach_filter); 1534 1535 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk) 1536 { 1537 struct bpf_prog *prog = __get_filter(fprog, sk); 1538 int err; 1539 1540 if (IS_ERR(prog)) 1541 return PTR_ERR(prog); 1542 1543 err = __reuseport_attach_prog(prog, sk); 1544 if (err < 0) { 1545 __bpf_prog_release(prog); 1546 return err; 1547 } 1548 1549 return 0; 1550 } 1551 1552 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk) 1553 { 1554 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 1555 return ERR_PTR(-EPERM); 1556 1557 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER); 1558 } 1559 1560 int sk_attach_bpf(u32 ufd, struct sock *sk) 1561 { 1562 struct bpf_prog *prog = __get_bpf(ufd, sk); 1563 int err; 1564 1565 if (IS_ERR(prog)) 1566 return PTR_ERR(prog); 1567 1568 err = __sk_attach_prog(prog, sk); 1569 if (err < 0) { 1570 bpf_prog_put(prog); 1571 return err; 1572 } 1573 1574 return 0; 1575 } 1576 1577 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk) 1578 { 1579 struct bpf_prog *prog = __get_bpf(ufd, sk); 1580 int err; 1581 1582 if (IS_ERR(prog)) 1583 return PTR_ERR(prog); 1584 1585 err = __reuseport_attach_prog(prog, sk); 1586 if (err < 0) { 1587 bpf_prog_put(prog); 1588 return err; 1589 } 1590 1591 return 0; 1592 } 1593 1594 struct bpf_scratchpad { 1595 union { 1596 __be32 diff[MAX_BPF_STACK / sizeof(__be32)]; 1597 u8 buff[MAX_BPF_STACK]; 1598 }; 1599 }; 1600 1601 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp); 1602 1603 static inline int __bpf_try_make_writable(struct sk_buff *skb, 1604 unsigned int write_len) 1605 { 1606 return skb_ensure_writable(skb, write_len); 1607 } 1608 1609 static inline int bpf_try_make_writable(struct sk_buff *skb, 1610 unsigned int write_len) 1611 { 1612 int err = __bpf_try_make_writable(skb, write_len); 1613 1614 bpf_compute_data_pointers(skb); 1615 return err; 1616 } 1617 1618 static int bpf_try_make_head_writable(struct sk_buff *skb) 1619 { 1620 return bpf_try_make_writable(skb, skb_headlen(skb)); 1621 } 1622 1623 static inline void bpf_push_mac_rcsum(struct sk_buff *skb) 1624 { 1625 if (skb_at_tc_ingress(skb)) 1626 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len); 1627 } 1628 1629 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb) 1630 { 1631 if (skb_at_tc_ingress(skb)) 1632 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len); 1633 } 1634 1635 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset, 1636 const void *, from, u32, len, u64, flags) 1637 { 1638 void *ptr; 1639 1640 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH))) 1641 return -EINVAL; 1642 if (unlikely(offset > 0xffff)) 1643 return -EFAULT; 1644 if (unlikely(bpf_try_make_writable(skb, offset + len))) 1645 return -EFAULT; 1646 1647 ptr = skb->data + offset; 1648 if (flags & BPF_F_RECOMPUTE_CSUM) 1649 __skb_postpull_rcsum(skb, ptr, len, offset); 1650 1651 memcpy(ptr, from, len); 1652 1653 if (flags & BPF_F_RECOMPUTE_CSUM) 1654 __skb_postpush_rcsum(skb, ptr, len, offset); 1655 if (flags & BPF_F_INVALIDATE_HASH) 1656 skb_clear_hash(skb); 1657 1658 return 0; 1659 } 1660 1661 static const struct bpf_func_proto bpf_skb_store_bytes_proto = { 1662 .func = bpf_skb_store_bytes, 1663 .gpl_only = false, 1664 .ret_type = RET_INTEGER, 1665 .arg1_type = ARG_PTR_TO_CTX, 1666 .arg2_type = ARG_ANYTHING, 1667 .arg3_type = ARG_PTR_TO_MEM, 1668 .arg4_type = ARG_CONST_SIZE, 1669 .arg5_type = ARG_ANYTHING, 1670 }; 1671 1672 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset, 1673 void *, to, u32, len) 1674 { 1675 void *ptr; 1676 1677 if (unlikely(offset > 0xffff)) 1678 goto err_clear; 1679 1680 ptr = skb_header_pointer(skb, offset, len, to); 1681 if (unlikely(!ptr)) 1682 goto err_clear; 1683 if (ptr != to) 1684 memcpy(to, ptr, len); 1685 1686 return 0; 1687 err_clear: 1688 memset(to, 0, len); 1689 return -EFAULT; 1690 } 1691 1692 static const struct bpf_func_proto bpf_skb_load_bytes_proto = { 1693 .func = bpf_skb_load_bytes, 1694 .gpl_only = false, 1695 .ret_type = RET_INTEGER, 1696 .arg1_type = ARG_PTR_TO_CTX, 1697 .arg2_type = ARG_ANYTHING, 1698 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 1699 .arg4_type = ARG_CONST_SIZE, 1700 }; 1701 1702 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb, 1703 u32, offset, void *, to, u32, len, u32, start_header) 1704 { 1705 u8 *ptr; 1706 1707 if (unlikely(offset > 0xffff || len > skb_headlen(skb))) 1708 goto err_clear; 1709 1710 switch (start_header) { 1711 case BPF_HDR_START_MAC: 1712 ptr = skb_mac_header(skb) + offset; 1713 break; 1714 case BPF_HDR_START_NET: 1715 ptr = skb_network_header(skb) + offset; 1716 break; 1717 default: 1718 goto err_clear; 1719 } 1720 1721 if (likely(ptr >= skb_mac_header(skb) && 1722 ptr + len <= skb_tail_pointer(skb))) { 1723 memcpy(to, ptr, len); 1724 return 0; 1725 } 1726 1727 err_clear: 1728 memset(to, 0, len); 1729 return -EFAULT; 1730 } 1731 1732 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = { 1733 .func = bpf_skb_load_bytes_relative, 1734 .gpl_only = false, 1735 .ret_type = RET_INTEGER, 1736 .arg1_type = ARG_PTR_TO_CTX, 1737 .arg2_type = ARG_ANYTHING, 1738 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 1739 .arg4_type = ARG_CONST_SIZE, 1740 .arg5_type = ARG_ANYTHING, 1741 }; 1742 1743 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len) 1744 { 1745 /* Idea is the following: should the needed direct read/write 1746 * test fail during runtime, we can pull in more data and redo 1747 * again, since implicitly, we invalidate previous checks here. 1748 * 1749 * Or, since we know how much we need to make read/writeable, 1750 * this can be done once at the program beginning for direct 1751 * access case. By this we overcome limitations of only current 1752 * headroom being accessible. 1753 */ 1754 return bpf_try_make_writable(skb, len ? : skb_headlen(skb)); 1755 } 1756 1757 static const struct bpf_func_proto bpf_skb_pull_data_proto = { 1758 .func = bpf_skb_pull_data, 1759 .gpl_only = false, 1760 .ret_type = RET_INTEGER, 1761 .arg1_type = ARG_PTR_TO_CTX, 1762 .arg2_type = ARG_ANYTHING, 1763 }; 1764 1765 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset, 1766 u64, from, u64, to, u64, flags) 1767 { 1768 __sum16 *ptr; 1769 1770 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK))) 1771 return -EINVAL; 1772 if (unlikely(offset > 0xffff || offset & 1)) 1773 return -EFAULT; 1774 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) 1775 return -EFAULT; 1776 1777 ptr = (__sum16 *)(skb->data + offset); 1778 switch (flags & BPF_F_HDR_FIELD_MASK) { 1779 case 0: 1780 if (unlikely(from != 0)) 1781 return -EINVAL; 1782 1783 csum_replace_by_diff(ptr, to); 1784 break; 1785 case 2: 1786 csum_replace2(ptr, from, to); 1787 break; 1788 case 4: 1789 csum_replace4(ptr, from, to); 1790 break; 1791 default: 1792 return -EINVAL; 1793 } 1794 1795 return 0; 1796 } 1797 1798 static const struct bpf_func_proto bpf_l3_csum_replace_proto = { 1799 .func = bpf_l3_csum_replace, 1800 .gpl_only = false, 1801 .ret_type = RET_INTEGER, 1802 .arg1_type = ARG_PTR_TO_CTX, 1803 .arg2_type = ARG_ANYTHING, 1804 .arg3_type = ARG_ANYTHING, 1805 .arg4_type = ARG_ANYTHING, 1806 .arg5_type = ARG_ANYTHING, 1807 }; 1808 1809 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset, 1810 u64, from, u64, to, u64, flags) 1811 { 1812 bool is_pseudo = flags & BPF_F_PSEUDO_HDR; 1813 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0; 1814 bool do_mforce = flags & BPF_F_MARK_ENFORCE; 1815 __sum16 *ptr; 1816 1817 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE | 1818 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK))) 1819 return -EINVAL; 1820 if (unlikely(offset > 0xffff || offset & 1)) 1821 return -EFAULT; 1822 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) 1823 return -EFAULT; 1824 1825 ptr = (__sum16 *)(skb->data + offset); 1826 if (is_mmzero && !do_mforce && !*ptr) 1827 return 0; 1828 1829 switch (flags & BPF_F_HDR_FIELD_MASK) { 1830 case 0: 1831 if (unlikely(from != 0)) 1832 return -EINVAL; 1833 1834 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo); 1835 break; 1836 case 2: 1837 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo); 1838 break; 1839 case 4: 1840 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo); 1841 break; 1842 default: 1843 return -EINVAL; 1844 } 1845 1846 if (is_mmzero && !*ptr) 1847 *ptr = CSUM_MANGLED_0; 1848 return 0; 1849 } 1850 1851 static const struct bpf_func_proto bpf_l4_csum_replace_proto = { 1852 .func = bpf_l4_csum_replace, 1853 .gpl_only = false, 1854 .ret_type = RET_INTEGER, 1855 .arg1_type = ARG_PTR_TO_CTX, 1856 .arg2_type = ARG_ANYTHING, 1857 .arg3_type = ARG_ANYTHING, 1858 .arg4_type = ARG_ANYTHING, 1859 .arg5_type = ARG_ANYTHING, 1860 }; 1861 1862 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size, 1863 __be32 *, to, u32, to_size, __wsum, seed) 1864 { 1865 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp); 1866 u32 diff_size = from_size + to_size; 1867 int i, j = 0; 1868 1869 /* This is quite flexible, some examples: 1870 * 1871 * from_size == 0, to_size > 0, seed := csum --> pushing data 1872 * from_size > 0, to_size == 0, seed := csum --> pulling data 1873 * from_size > 0, to_size > 0, seed := 0 --> diffing data 1874 * 1875 * Even for diffing, from_size and to_size don't need to be equal. 1876 */ 1877 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) || 1878 diff_size > sizeof(sp->diff))) 1879 return -EINVAL; 1880 1881 for (i = 0; i < from_size / sizeof(__be32); i++, j++) 1882 sp->diff[j] = ~from[i]; 1883 for (i = 0; i < to_size / sizeof(__be32); i++, j++) 1884 sp->diff[j] = to[i]; 1885 1886 return csum_partial(sp->diff, diff_size, seed); 1887 } 1888 1889 static const struct bpf_func_proto bpf_csum_diff_proto = { 1890 .func = bpf_csum_diff, 1891 .gpl_only = false, 1892 .pkt_access = true, 1893 .ret_type = RET_INTEGER, 1894 .arg1_type = ARG_PTR_TO_MEM_OR_NULL, 1895 .arg2_type = ARG_CONST_SIZE_OR_ZERO, 1896 .arg3_type = ARG_PTR_TO_MEM_OR_NULL, 1897 .arg4_type = ARG_CONST_SIZE_OR_ZERO, 1898 .arg5_type = ARG_ANYTHING, 1899 }; 1900 1901 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum) 1902 { 1903 /* The interface is to be used in combination with bpf_csum_diff() 1904 * for direct packet writes. csum rotation for alignment as well 1905 * as emulating csum_sub() can be done from the eBPF program. 1906 */ 1907 if (skb->ip_summed == CHECKSUM_COMPLETE) 1908 return (skb->csum = csum_add(skb->csum, csum)); 1909 1910 return -ENOTSUPP; 1911 } 1912 1913 static const struct bpf_func_proto bpf_csum_update_proto = { 1914 .func = bpf_csum_update, 1915 .gpl_only = false, 1916 .ret_type = RET_INTEGER, 1917 .arg1_type = ARG_PTR_TO_CTX, 1918 .arg2_type = ARG_ANYTHING, 1919 }; 1920 1921 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb) 1922 { 1923 return dev_forward_skb(dev, skb); 1924 } 1925 1926 static inline int __bpf_rx_skb_no_mac(struct net_device *dev, 1927 struct sk_buff *skb) 1928 { 1929 int ret = ____dev_forward_skb(dev, skb); 1930 1931 if (likely(!ret)) { 1932 skb->dev = dev; 1933 ret = netif_rx(skb); 1934 } 1935 1936 return ret; 1937 } 1938 1939 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) 1940 { 1941 int ret; 1942 1943 if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) { 1944 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n"); 1945 kfree_skb(skb); 1946 return -ENETDOWN; 1947 } 1948 1949 skb->dev = dev; 1950 1951 __this_cpu_inc(xmit_recursion); 1952 ret = dev_queue_xmit(skb); 1953 __this_cpu_dec(xmit_recursion); 1954 1955 return ret; 1956 } 1957 1958 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev, 1959 u32 flags) 1960 { 1961 /* skb->mac_len is not set on normal egress */ 1962 unsigned int mlen = skb->network_header - skb->mac_header; 1963 1964 __skb_pull(skb, mlen); 1965 1966 /* At ingress, the mac header has already been pulled once. 1967 * At egress, skb_pospull_rcsum has to be done in case that 1968 * the skb is originated from ingress (i.e. a forwarded skb) 1969 * to ensure that rcsum starts at net header. 1970 */ 1971 if (!skb_at_tc_ingress(skb)) 1972 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen); 1973 skb_pop_mac_header(skb); 1974 skb_reset_mac_len(skb); 1975 return flags & BPF_F_INGRESS ? 1976 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb); 1977 } 1978 1979 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev, 1980 u32 flags) 1981 { 1982 /* Verify that a link layer header is carried */ 1983 if (unlikely(skb->mac_header >= skb->network_header)) { 1984 kfree_skb(skb); 1985 return -ERANGE; 1986 } 1987 1988 bpf_push_mac_rcsum(skb); 1989 return flags & BPF_F_INGRESS ? 1990 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb); 1991 } 1992 1993 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev, 1994 u32 flags) 1995 { 1996 if (dev_is_mac_header_xmit(dev)) 1997 return __bpf_redirect_common(skb, dev, flags); 1998 else 1999 return __bpf_redirect_no_mac(skb, dev, flags); 2000 } 2001 2002 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags) 2003 { 2004 struct net_device *dev; 2005 struct sk_buff *clone; 2006 int ret; 2007 2008 if (unlikely(flags & ~(BPF_F_INGRESS))) 2009 return -EINVAL; 2010 2011 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex); 2012 if (unlikely(!dev)) 2013 return -EINVAL; 2014 2015 clone = skb_clone(skb, GFP_ATOMIC); 2016 if (unlikely(!clone)) 2017 return -ENOMEM; 2018 2019 /* For direct write, we need to keep the invariant that the skbs 2020 * we're dealing with need to be uncloned. Should uncloning fail 2021 * here, we need to free the just generated clone to unclone once 2022 * again. 2023 */ 2024 ret = bpf_try_make_head_writable(skb); 2025 if (unlikely(ret)) { 2026 kfree_skb(clone); 2027 return -ENOMEM; 2028 } 2029 2030 return __bpf_redirect(clone, dev, flags); 2031 } 2032 2033 static const struct bpf_func_proto bpf_clone_redirect_proto = { 2034 .func = bpf_clone_redirect, 2035 .gpl_only = false, 2036 .ret_type = RET_INTEGER, 2037 .arg1_type = ARG_PTR_TO_CTX, 2038 .arg2_type = ARG_ANYTHING, 2039 .arg3_type = ARG_ANYTHING, 2040 }; 2041 2042 struct redirect_info { 2043 u32 ifindex; 2044 u32 flags; 2045 struct bpf_map *map; 2046 struct bpf_map *map_to_flush; 2047 unsigned long map_owner; 2048 }; 2049 2050 static DEFINE_PER_CPU(struct redirect_info, redirect_info); 2051 2052 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags) 2053 { 2054 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 2055 2056 if (unlikely(flags & ~(BPF_F_INGRESS))) 2057 return TC_ACT_SHOT; 2058 2059 ri->ifindex = ifindex; 2060 ri->flags = flags; 2061 2062 return TC_ACT_REDIRECT; 2063 } 2064 2065 int skb_do_redirect(struct sk_buff *skb) 2066 { 2067 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 2068 struct net_device *dev; 2069 2070 dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex); 2071 ri->ifindex = 0; 2072 if (unlikely(!dev)) { 2073 kfree_skb(skb); 2074 return -EINVAL; 2075 } 2076 2077 return __bpf_redirect(skb, dev, ri->flags); 2078 } 2079 2080 static const struct bpf_func_proto bpf_redirect_proto = { 2081 .func = bpf_redirect, 2082 .gpl_only = false, 2083 .ret_type = RET_INTEGER, 2084 .arg1_type = ARG_ANYTHING, 2085 .arg2_type = ARG_ANYTHING, 2086 }; 2087 2088 BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb, 2089 struct bpf_map *, map, void *, key, u64, flags) 2090 { 2091 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); 2092 2093 /* If user passes invalid input drop the packet. */ 2094 if (unlikely(flags & ~(BPF_F_INGRESS))) 2095 return SK_DROP; 2096 2097 tcb->bpf.flags = flags; 2098 tcb->bpf.sk_redir = __sock_hash_lookup_elem(map, key); 2099 if (!tcb->bpf.sk_redir) 2100 return SK_DROP; 2101 2102 return SK_PASS; 2103 } 2104 2105 static const struct bpf_func_proto bpf_sk_redirect_hash_proto = { 2106 .func = bpf_sk_redirect_hash, 2107 .gpl_only = false, 2108 .ret_type = RET_INTEGER, 2109 .arg1_type = ARG_PTR_TO_CTX, 2110 .arg2_type = ARG_CONST_MAP_PTR, 2111 .arg3_type = ARG_PTR_TO_MAP_KEY, 2112 .arg4_type = ARG_ANYTHING, 2113 }; 2114 2115 BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb, 2116 struct bpf_map *, map, u32, key, u64, flags) 2117 { 2118 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); 2119 2120 /* If user passes invalid input drop the packet. */ 2121 if (unlikely(flags & ~(BPF_F_INGRESS))) 2122 return SK_DROP; 2123 2124 tcb->bpf.flags = flags; 2125 tcb->bpf.sk_redir = __sock_map_lookup_elem(map, key); 2126 if (!tcb->bpf.sk_redir) 2127 return SK_DROP; 2128 2129 return SK_PASS; 2130 } 2131 2132 struct sock *do_sk_redirect_map(struct sk_buff *skb) 2133 { 2134 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); 2135 2136 return tcb->bpf.sk_redir; 2137 } 2138 2139 static const struct bpf_func_proto bpf_sk_redirect_map_proto = { 2140 .func = bpf_sk_redirect_map, 2141 .gpl_only = false, 2142 .ret_type = RET_INTEGER, 2143 .arg1_type = ARG_PTR_TO_CTX, 2144 .arg2_type = ARG_CONST_MAP_PTR, 2145 .arg3_type = ARG_ANYTHING, 2146 .arg4_type = ARG_ANYTHING, 2147 }; 2148 2149 BPF_CALL_4(bpf_msg_redirect_hash, struct sk_msg_buff *, msg, 2150 struct bpf_map *, map, void *, key, u64, flags) 2151 { 2152 /* If user passes invalid input drop the packet. */ 2153 if (unlikely(flags & ~(BPF_F_INGRESS))) 2154 return SK_DROP; 2155 2156 msg->flags = flags; 2157 msg->sk_redir = __sock_hash_lookup_elem(map, key); 2158 if (!msg->sk_redir) 2159 return SK_DROP; 2160 2161 return SK_PASS; 2162 } 2163 2164 static const struct bpf_func_proto bpf_msg_redirect_hash_proto = { 2165 .func = bpf_msg_redirect_hash, 2166 .gpl_only = false, 2167 .ret_type = RET_INTEGER, 2168 .arg1_type = ARG_PTR_TO_CTX, 2169 .arg2_type = ARG_CONST_MAP_PTR, 2170 .arg3_type = ARG_PTR_TO_MAP_KEY, 2171 .arg4_type = ARG_ANYTHING, 2172 }; 2173 2174 BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg_buff *, msg, 2175 struct bpf_map *, map, u32, key, u64, flags) 2176 { 2177 /* If user passes invalid input drop the packet. */ 2178 if (unlikely(flags & ~(BPF_F_INGRESS))) 2179 return SK_DROP; 2180 2181 msg->flags = flags; 2182 msg->sk_redir = __sock_map_lookup_elem(map, key); 2183 if (!msg->sk_redir) 2184 return SK_DROP; 2185 2186 return SK_PASS; 2187 } 2188 2189 struct sock *do_msg_redirect_map(struct sk_msg_buff *msg) 2190 { 2191 return msg->sk_redir; 2192 } 2193 2194 static const struct bpf_func_proto bpf_msg_redirect_map_proto = { 2195 .func = bpf_msg_redirect_map, 2196 .gpl_only = false, 2197 .ret_type = RET_INTEGER, 2198 .arg1_type = ARG_PTR_TO_CTX, 2199 .arg2_type = ARG_CONST_MAP_PTR, 2200 .arg3_type = ARG_ANYTHING, 2201 .arg4_type = ARG_ANYTHING, 2202 }; 2203 2204 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg_buff *, msg, u32, bytes) 2205 { 2206 msg->apply_bytes = bytes; 2207 return 0; 2208 } 2209 2210 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = { 2211 .func = bpf_msg_apply_bytes, 2212 .gpl_only = false, 2213 .ret_type = RET_INTEGER, 2214 .arg1_type = ARG_PTR_TO_CTX, 2215 .arg2_type = ARG_ANYTHING, 2216 }; 2217 2218 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg_buff *, msg, u32, bytes) 2219 { 2220 msg->cork_bytes = bytes; 2221 return 0; 2222 } 2223 2224 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = { 2225 .func = bpf_msg_cork_bytes, 2226 .gpl_only = false, 2227 .ret_type = RET_INTEGER, 2228 .arg1_type = ARG_PTR_TO_CTX, 2229 .arg2_type = ARG_ANYTHING, 2230 }; 2231 2232 BPF_CALL_4(bpf_msg_pull_data, 2233 struct sk_msg_buff *, msg, u32, start, u32, end, u64, flags) 2234 { 2235 unsigned int len = 0, offset = 0, copy = 0; 2236 struct scatterlist *sg = msg->sg_data; 2237 int first_sg, last_sg, i, shift; 2238 unsigned char *p, *to, *from; 2239 int bytes = end - start; 2240 struct page *page; 2241 2242 if (unlikely(flags || end <= start)) 2243 return -EINVAL; 2244 2245 /* First find the starting scatterlist element */ 2246 i = msg->sg_start; 2247 do { 2248 len = sg[i].length; 2249 offset += len; 2250 if (start < offset + len) 2251 break; 2252 i++; 2253 if (i == MAX_SKB_FRAGS) 2254 i = 0; 2255 } while (i != msg->sg_end); 2256 2257 if (unlikely(start >= offset + len)) 2258 return -EINVAL; 2259 2260 if (!msg->sg_copy[i] && bytes <= len) 2261 goto out; 2262 2263 first_sg = i; 2264 2265 /* At this point we need to linearize multiple scatterlist 2266 * elements or a single shared page. Either way we need to 2267 * copy into a linear buffer exclusively owned by BPF. Then 2268 * place the buffer in the scatterlist and fixup the original 2269 * entries by removing the entries now in the linear buffer 2270 * and shifting the remaining entries. For now we do not try 2271 * to copy partial entries to avoid complexity of running out 2272 * of sg_entry slots. The downside is reading a single byte 2273 * will copy the entire sg entry. 2274 */ 2275 do { 2276 copy += sg[i].length; 2277 i++; 2278 if (i == MAX_SKB_FRAGS) 2279 i = 0; 2280 if (bytes < copy) 2281 break; 2282 } while (i != msg->sg_end); 2283 last_sg = i; 2284 2285 if (unlikely(copy < end - start)) 2286 return -EINVAL; 2287 2288 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC, get_order(copy)); 2289 if (unlikely(!page)) 2290 return -ENOMEM; 2291 p = page_address(page); 2292 offset = 0; 2293 2294 i = first_sg; 2295 do { 2296 from = sg_virt(&sg[i]); 2297 len = sg[i].length; 2298 to = p + offset; 2299 2300 memcpy(to, from, len); 2301 offset += len; 2302 sg[i].length = 0; 2303 put_page(sg_page(&sg[i])); 2304 2305 i++; 2306 if (i == MAX_SKB_FRAGS) 2307 i = 0; 2308 } while (i != last_sg); 2309 2310 sg[first_sg].length = copy; 2311 sg_set_page(&sg[first_sg], page, copy, 0); 2312 2313 /* To repair sg ring we need to shift entries. If we only 2314 * had a single entry though we can just replace it and 2315 * be done. Otherwise walk the ring and shift the entries. 2316 */ 2317 shift = last_sg - first_sg - 1; 2318 if (!shift) 2319 goto out; 2320 2321 i = first_sg + 1; 2322 do { 2323 int move_from; 2324 2325 if (i + shift >= MAX_SKB_FRAGS) 2326 move_from = i + shift - MAX_SKB_FRAGS; 2327 else 2328 move_from = i + shift; 2329 2330 if (move_from == msg->sg_end) 2331 break; 2332 2333 sg[i] = sg[move_from]; 2334 sg[move_from].length = 0; 2335 sg[move_from].page_link = 0; 2336 sg[move_from].offset = 0; 2337 2338 i++; 2339 if (i == MAX_SKB_FRAGS) 2340 i = 0; 2341 } while (1); 2342 msg->sg_end -= shift; 2343 if (msg->sg_end < 0) 2344 msg->sg_end += MAX_SKB_FRAGS; 2345 out: 2346 msg->data = sg_virt(&sg[i]) + start - offset; 2347 msg->data_end = msg->data + bytes; 2348 2349 return 0; 2350 } 2351 2352 static const struct bpf_func_proto bpf_msg_pull_data_proto = { 2353 .func = bpf_msg_pull_data, 2354 .gpl_only = false, 2355 .ret_type = RET_INTEGER, 2356 .arg1_type = ARG_PTR_TO_CTX, 2357 .arg2_type = ARG_ANYTHING, 2358 .arg3_type = ARG_ANYTHING, 2359 .arg4_type = ARG_ANYTHING, 2360 }; 2361 2362 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb) 2363 { 2364 return task_get_classid(skb); 2365 } 2366 2367 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = { 2368 .func = bpf_get_cgroup_classid, 2369 .gpl_only = false, 2370 .ret_type = RET_INTEGER, 2371 .arg1_type = ARG_PTR_TO_CTX, 2372 }; 2373 2374 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb) 2375 { 2376 return dst_tclassid(skb); 2377 } 2378 2379 static const struct bpf_func_proto bpf_get_route_realm_proto = { 2380 .func = bpf_get_route_realm, 2381 .gpl_only = false, 2382 .ret_type = RET_INTEGER, 2383 .arg1_type = ARG_PTR_TO_CTX, 2384 }; 2385 2386 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb) 2387 { 2388 /* If skb_clear_hash() was called due to mangling, we can 2389 * trigger SW recalculation here. Later access to hash 2390 * can then use the inline skb->hash via context directly 2391 * instead of calling this helper again. 2392 */ 2393 return skb_get_hash(skb); 2394 } 2395 2396 static const struct bpf_func_proto bpf_get_hash_recalc_proto = { 2397 .func = bpf_get_hash_recalc, 2398 .gpl_only = false, 2399 .ret_type = RET_INTEGER, 2400 .arg1_type = ARG_PTR_TO_CTX, 2401 }; 2402 2403 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb) 2404 { 2405 /* After all direct packet write, this can be used once for 2406 * triggering a lazy recalc on next skb_get_hash() invocation. 2407 */ 2408 skb_clear_hash(skb); 2409 return 0; 2410 } 2411 2412 static const struct bpf_func_proto bpf_set_hash_invalid_proto = { 2413 .func = bpf_set_hash_invalid, 2414 .gpl_only = false, 2415 .ret_type = RET_INTEGER, 2416 .arg1_type = ARG_PTR_TO_CTX, 2417 }; 2418 2419 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash) 2420 { 2421 /* Set user specified hash as L4(+), so that it gets returned 2422 * on skb_get_hash() call unless BPF prog later on triggers a 2423 * skb_clear_hash(). 2424 */ 2425 __skb_set_sw_hash(skb, hash, true); 2426 return 0; 2427 } 2428 2429 static const struct bpf_func_proto bpf_set_hash_proto = { 2430 .func = bpf_set_hash, 2431 .gpl_only = false, 2432 .ret_type = RET_INTEGER, 2433 .arg1_type = ARG_PTR_TO_CTX, 2434 .arg2_type = ARG_ANYTHING, 2435 }; 2436 2437 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto, 2438 u16, vlan_tci) 2439 { 2440 int ret; 2441 2442 if (unlikely(vlan_proto != htons(ETH_P_8021Q) && 2443 vlan_proto != htons(ETH_P_8021AD))) 2444 vlan_proto = htons(ETH_P_8021Q); 2445 2446 bpf_push_mac_rcsum(skb); 2447 ret = skb_vlan_push(skb, vlan_proto, vlan_tci); 2448 bpf_pull_mac_rcsum(skb); 2449 2450 bpf_compute_data_pointers(skb); 2451 return ret; 2452 } 2453 2454 static const struct bpf_func_proto bpf_skb_vlan_push_proto = { 2455 .func = bpf_skb_vlan_push, 2456 .gpl_only = false, 2457 .ret_type = RET_INTEGER, 2458 .arg1_type = ARG_PTR_TO_CTX, 2459 .arg2_type = ARG_ANYTHING, 2460 .arg3_type = ARG_ANYTHING, 2461 }; 2462 2463 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb) 2464 { 2465 int ret; 2466 2467 bpf_push_mac_rcsum(skb); 2468 ret = skb_vlan_pop(skb); 2469 bpf_pull_mac_rcsum(skb); 2470 2471 bpf_compute_data_pointers(skb); 2472 return ret; 2473 } 2474 2475 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = { 2476 .func = bpf_skb_vlan_pop, 2477 .gpl_only = false, 2478 .ret_type = RET_INTEGER, 2479 .arg1_type = ARG_PTR_TO_CTX, 2480 }; 2481 2482 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len) 2483 { 2484 /* Caller already did skb_cow() with len as headroom, 2485 * so no need to do it here. 2486 */ 2487 skb_push(skb, len); 2488 memmove(skb->data, skb->data + len, off); 2489 memset(skb->data + off, 0, len); 2490 2491 /* No skb_postpush_rcsum(skb, skb->data + off, len) 2492 * needed here as it does not change the skb->csum 2493 * result for checksum complete when summing over 2494 * zeroed blocks. 2495 */ 2496 return 0; 2497 } 2498 2499 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len) 2500 { 2501 /* skb_ensure_writable() is not needed here, as we're 2502 * already working on an uncloned skb. 2503 */ 2504 if (unlikely(!pskb_may_pull(skb, off + len))) 2505 return -ENOMEM; 2506 2507 skb_postpull_rcsum(skb, skb->data + off, len); 2508 memmove(skb->data + len, skb->data, off); 2509 __skb_pull(skb, len); 2510 2511 return 0; 2512 } 2513 2514 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len) 2515 { 2516 bool trans_same = skb->transport_header == skb->network_header; 2517 int ret; 2518 2519 /* There's no need for __skb_push()/__skb_pull() pair to 2520 * get to the start of the mac header as we're guaranteed 2521 * to always start from here under eBPF. 2522 */ 2523 ret = bpf_skb_generic_push(skb, off, len); 2524 if (likely(!ret)) { 2525 skb->mac_header -= len; 2526 skb->network_header -= len; 2527 if (trans_same) 2528 skb->transport_header = skb->network_header; 2529 } 2530 2531 return ret; 2532 } 2533 2534 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len) 2535 { 2536 bool trans_same = skb->transport_header == skb->network_header; 2537 int ret; 2538 2539 /* Same here, __skb_push()/__skb_pull() pair not needed. */ 2540 ret = bpf_skb_generic_pop(skb, off, len); 2541 if (likely(!ret)) { 2542 skb->mac_header += len; 2543 skb->network_header += len; 2544 if (trans_same) 2545 skb->transport_header = skb->network_header; 2546 } 2547 2548 return ret; 2549 } 2550 2551 static int bpf_skb_proto_4_to_6(struct sk_buff *skb) 2552 { 2553 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); 2554 u32 off = skb_mac_header_len(skb); 2555 int ret; 2556 2557 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2558 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2559 return -ENOTSUPP; 2560 2561 ret = skb_cow(skb, len_diff); 2562 if (unlikely(ret < 0)) 2563 return ret; 2564 2565 ret = bpf_skb_net_hdr_push(skb, off, len_diff); 2566 if (unlikely(ret < 0)) 2567 return ret; 2568 2569 if (skb_is_gso(skb)) { 2570 struct skb_shared_info *shinfo = skb_shinfo(skb); 2571 2572 /* SKB_GSO_TCPV4 needs to be changed into 2573 * SKB_GSO_TCPV6. 2574 */ 2575 if (shinfo->gso_type & SKB_GSO_TCPV4) { 2576 shinfo->gso_type &= ~SKB_GSO_TCPV4; 2577 shinfo->gso_type |= SKB_GSO_TCPV6; 2578 } 2579 2580 /* Due to IPv6 header, MSS needs to be downgraded. */ 2581 skb_decrease_gso_size(shinfo, len_diff); 2582 /* Header must be checked, and gso_segs recomputed. */ 2583 shinfo->gso_type |= SKB_GSO_DODGY; 2584 shinfo->gso_segs = 0; 2585 } 2586 2587 skb->protocol = htons(ETH_P_IPV6); 2588 skb_clear_hash(skb); 2589 2590 return 0; 2591 } 2592 2593 static int bpf_skb_proto_6_to_4(struct sk_buff *skb) 2594 { 2595 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); 2596 u32 off = skb_mac_header_len(skb); 2597 int ret; 2598 2599 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2600 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2601 return -ENOTSUPP; 2602 2603 ret = skb_unclone(skb, GFP_ATOMIC); 2604 if (unlikely(ret < 0)) 2605 return ret; 2606 2607 ret = bpf_skb_net_hdr_pop(skb, off, len_diff); 2608 if (unlikely(ret < 0)) 2609 return ret; 2610 2611 if (skb_is_gso(skb)) { 2612 struct skb_shared_info *shinfo = skb_shinfo(skb); 2613 2614 /* SKB_GSO_TCPV6 needs to be changed into 2615 * SKB_GSO_TCPV4. 2616 */ 2617 if (shinfo->gso_type & SKB_GSO_TCPV6) { 2618 shinfo->gso_type &= ~SKB_GSO_TCPV6; 2619 shinfo->gso_type |= SKB_GSO_TCPV4; 2620 } 2621 2622 /* Due to IPv4 header, MSS can be upgraded. */ 2623 skb_increase_gso_size(shinfo, len_diff); 2624 /* Header must be checked, and gso_segs recomputed. */ 2625 shinfo->gso_type |= SKB_GSO_DODGY; 2626 shinfo->gso_segs = 0; 2627 } 2628 2629 skb->protocol = htons(ETH_P_IP); 2630 skb_clear_hash(skb); 2631 2632 return 0; 2633 } 2634 2635 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto) 2636 { 2637 __be16 from_proto = skb->protocol; 2638 2639 if (from_proto == htons(ETH_P_IP) && 2640 to_proto == htons(ETH_P_IPV6)) 2641 return bpf_skb_proto_4_to_6(skb); 2642 2643 if (from_proto == htons(ETH_P_IPV6) && 2644 to_proto == htons(ETH_P_IP)) 2645 return bpf_skb_proto_6_to_4(skb); 2646 2647 return -ENOTSUPP; 2648 } 2649 2650 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto, 2651 u64, flags) 2652 { 2653 int ret; 2654 2655 if (unlikely(flags)) 2656 return -EINVAL; 2657 2658 /* General idea is that this helper does the basic groundwork 2659 * needed for changing the protocol, and eBPF program fills the 2660 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace() 2661 * and other helpers, rather than passing a raw buffer here. 2662 * 2663 * The rationale is to keep this minimal and without a need to 2664 * deal with raw packet data. F.e. even if we would pass buffers 2665 * here, the program still needs to call the bpf_lX_csum_replace() 2666 * helpers anyway. Plus, this way we keep also separation of 2667 * concerns, since f.e. bpf_skb_store_bytes() should only take 2668 * care of stores. 2669 * 2670 * Currently, additional options and extension header space are 2671 * not supported, but flags register is reserved so we can adapt 2672 * that. For offloads, we mark packet as dodgy, so that headers 2673 * need to be verified first. 2674 */ 2675 ret = bpf_skb_proto_xlat(skb, proto); 2676 bpf_compute_data_pointers(skb); 2677 return ret; 2678 } 2679 2680 static const struct bpf_func_proto bpf_skb_change_proto_proto = { 2681 .func = bpf_skb_change_proto, 2682 .gpl_only = false, 2683 .ret_type = RET_INTEGER, 2684 .arg1_type = ARG_PTR_TO_CTX, 2685 .arg2_type = ARG_ANYTHING, 2686 .arg3_type = ARG_ANYTHING, 2687 }; 2688 2689 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type) 2690 { 2691 /* We only allow a restricted subset to be changed for now. */ 2692 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) || 2693 !skb_pkt_type_ok(pkt_type))) 2694 return -EINVAL; 2695 2696 skb->pkt_type = pkt_type; 2697 return 0; 2698 } 2699 2700 static const struct bpf_func_proto bpf_skb_change_type_proto = { 2701 .func = bpf_skb_change_type, 2702 .gpl_only = false, 2703 .ret_type = RET_INTEGER, 2704 .arg1_type = ARG_PTR_TO_CTX, 2705 .arg2_type = ARG_ANYTHING, 2706 }; 2707 2708 static u32 bpf_skb_net_base_len(const struct sk_buff *skb) 2709 { 2710 switch (skb->protocol) { 2711 case htons(ETH_P_IP): 2712 return sizeof(struct iphdr); 2713 case htons(ETH_P_IPV6): 2714 return sizeof(struct ipv6hdr); 2715 default: 2716 return ~0U; 2717 } 2718 } 2719 2720 static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff) 2721 { 2722 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); 2723 int ret; 2724 2725 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2726 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2727 return -ENOTSUPP; 2728 2729 ret = skb_cow(skb, len_diff); 2730 if (unlikely(ret < 0)) 2731 return ret; 2732 2733 ret = bpf_skb_net_hdr_push(skb, off, len_diff); 2734 if (unlikely(ret < 0)) 2735 return ret; 2736 2737 if (skb_is_gso(skb)) { 2738 struct skb_shared_info *shinfo = skb_shinfo(skb); 2739 2740 /* Due to header grow, MSS needs to be downgraded. */ 2741 skb_decrease_gso_size(shinfo, len_diff); 2742 /* Header must be checked, and gso_segs recomputed. */ 2743 shinfo->gso_type |= SKB_GSO_DODGY; 2744 shinfo->gso_segs = 0; 2745 } 2746 2747 return 0; 2748 } 2749 2750 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff) 2751 { 2752 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); 2753 int ret; 2754 2755 /* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */ 2756 if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb))) 2757 return -ENOTSUPP; 2758 2759 ret = skb_unclone(skb, GFP_ATOMIC); 2760 if (unlikely(ret < 0)) 2761 return ret; 2762 2763 ret = bpf_skb_net_hdr_pop(skb, off, len_diff); 2764 if (unlikely(ret < 0)) 2765 return ret; 2766 2767 if (skb_is_gso(skb)) { 2768 struct skb_shared_info *shinfo = skb_shinfo(skb); 2769 2770 /* Due to header shrink, MSS can be upgraded. */ 2771 skb_increase_gso_size(shinfo, len_diff); 2772 /* Header must be checked, and gso_segs recomputed. */ 2773 shinfo->gso_type |= SKB_GSO_DODGY; 2774 shinfo->gso_segs = 0; 2775 } 2776 2777 return 0; 2778 } 2779 2780 static u32 __bpf_skb_max_len(const struct sk_buff *skb) 2781 { 2782 return skb->dev->mtu + skb->dev->hard_header_len; 2783 } 2784 2785 static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff) 2786 { 2787 bool trans_same = skb->transport_header == skb->network_header; 2788 u32 len_cur, len_diff_abs = abs(len_diff); 2789 u32 len_min = bpf_skb_net_base_len(skb); 2790 u32 len_max = __bpf_skb_max_len(skb); 2791 __be16 proto = skb->protocol; 2792 bool shrink = len_diff < 0; 2793 int ret; 2794 2795 if (unlikely(len_diff_abs > 0xfffU)) 2796 return -EFAULT; 2797 if (unlikely(proto != htons(ETH_P_IP) && 2798 proto != htons(ETH_P_IPV6))) 2799 return -ENOTSUPP; 2800 2801 len_cur = skb->len - skb_network_offset(skb); 2802 if (skb_transport_header_was_set(skb) && !trans_same) 2803 len_cur = skb_network_header_len(skb); 2804 if ((shrink && (len_diff_abs >= len_cur || 2805 len_cur - len_diff_abs < len_min)) || 2806 (!shrink && (skb->len + len_diff_abs > len_max && 2807 !skb_is_gso(skb)))) 2808 return -ENOTSUPP; 2809 2810 ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) : 2811 bpf_skb_net_grow(skb, len_diff_abs); 2812 2813 bpf_compute_data_pointers(skb); 2814 return ret; 2815 } 2816 2817 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff, 2818 u32, mode, u64, flags) 2819 { 2820 if (unlikely(flags)) 2821 return -EINVAL; 2822 if (likely(mode == BPF_ADJ_ROOM_NET)) 2823 return bpf_skb_adjust_net(skb, len_diff); 2824 2825 return -ENOTSUPP; 2826 } 2827 2828 static const struct bpf_func_proto bpf_skb_adjust_room_proto = { 2829 .func = bpf_skb_adjust_room, 2830 .gpl_only = false, 2831 .ret_type = RET_INTEGER, 2832 .arg1_type = ARG_PTR_TO_CTX, 2833 .arg2_type = ARG_ANYTHING, 2834 .arg3_type = ARG_ANYTHING, 2835 .arg4_type = ARG_ANYTHING, 2836 }; 2837 2838 static u32 __bpf_skb_min_len(const struct sk_buff *skb) 2839 { 2840 u32 min_len = skb_network_offset(skb); 2841 2842 if (skb_transport_header_was_set(skb)) 2843 min_len = skb_transport_offset(skb); 2844 if (skb->ip_summed == CHECKSUM_PARTIAL) 2845 min_len = skb_checksum_start_offset(skb) + 2846 skb->csum_offset + sizeof(__sum16); 2847 return min_len; 2848 } 2849 2850 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len) 2851 { 2852 unsigned int old_len = skb->len; 2853 int ret; 2854 2855 ret = __skb_grow_rcsum(skb, new_len); 2856 if (!ret) 2857 memset(skb->data + old_len, 0, new_len - old_len); 2858 return ret; 2859 } 2860 2861 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len) 2862 { 2863 return __skb_trim_rcsum(skb, new_len); 2864 } 2865 2866 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len, 2867 u64, flags) 2868 { 2869 u32 max_len = __bpf_skb_max_len(skb); 2870 u32 min_len = __bpf_skb_min_len(skb); 2871 int ret; 2872 2873 if (unlikely(flags || new_len > max_len || new_len < min_len)) 2874 return -EINVAL; 2875 if (skb->encapsulation) 2876 return -ENOTSUPP; 2877 2878 /* The basic idea of this helper is that it's performing the 2879 * needed work to either grow or trim an skb, and eBPF program 2880 * rewrites the rest via helpers like bpf_skb_store_bytes(), 2881 * bpf_lX_csum_replace() and others rather than passing a raw 2882 * buffer here. This one is a slow path helper and intended 2883 * for replies with control messages. 2884 * 2885 * Like in bpf_skb_change_proto(), we want to keep this rather 2886 * minimal and without protocol specifics so that we are able 2887 * to separate concerns as in bpf_skb_store_bytes() should only 2888 * be the one responsible for writing buffers. 2889 * 2890 * It's really expected to be a slow path operation here for 2891 * control message replies, so we're implicitly linearizing, 2892 * uncloning and drop offloads from the skb by this. 2893 */ 2894 ret = __bpf_try_make_writable(skb, skb->len); 2895 if (!ret) { 2896 if (new_len > skb->len) 2897 ret = bpf_skb_grow_rcsum(skb, new_len); 2898 else if (new_len < skb->len) 2899 ret = bpf_skb_trim_rcsum(skb, new_len); 2900 if (!ret && skb_is_gso(skb)) 2901 skb_gso_reset(skb); 2902 } 2903 2904 bpf_compute_data_pointers(skb); 2905 return ret; 2906 } 2907 2908 static const struct bpf_func_proto bpf_skb_change_tail_proto = { 2909 .func = bpf_skb_change_tail, 2910 .gpl_only = false, 2911 .ret_type = RET_INTEGER, 2912 .arg1_type = ARG_PTR_TO_CTX, 2913 .arg2_type = ARG_ANYTHING, 2914 .arg3_type = ARG_ANYTHING, 2915 }; 2916 2917 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room, 2918 u64, flags) 2919 { 2920 u32 max_len = __bpf_skb_max_len(skb); 2921 u32 new_len = skb->len + head_room; 2922 int ret; 2923 2924 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) || 2925 new_len < skb->len)) 2926 return -EINVAL; 2927 2928 ret = skb_cow(skb, head_room); 2929 if (likely(!ret)) { 2930 /* Idea for this helper is that we currently only 2931 * allow to expand on mac header. This means that 2932 * skb->protocol network header, etc, stay as is. 2933 * Compared to bpf_skb_change_tail(), we're more 2934 * flexible due to not needing to linearize or 2935 * reset GSO. Intention for this helper is to be 2936 * used by an L3 skb that needs to push mac header 2937 * for redirection into L2 device. 2938 */ 2939 __skb_push(skb, head_room); 2940 memset(skb->data, 0, head_room); 2941 skb_reset_mac_header(skb); 2942 } 2943 2944 bpf_compute_data_pointers(skb); 2945 return 0; 2946 } 2947 2948 static const struct bpf_func_proto bpf_skb_change_head_proto = { 2949 .func = bpf_skb_change_head, 2950 .gpl_only = false, 2951 .ret_type = RET_INTEGER, 2952 .arg1_type = ARG_PTR_TO_CTX, 2953 .arg2_type = ARG_ANYTHING, 2954 .arg3_type = ARG_ANYTHING, 2955 }; 2956 2957 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp) 2958 { 2959 return xdp_data_meta_unsupported(xdp) ? 0 : 2960 xdp->data - xdp->data_meta; 2961 } 2962 2963 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset) 2964 { 2965 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); 2966 unsigned long metalen = xdp_get_metalen(xdp); 2967 void *data_start = xdp_frame_end + metalen; 2968 void *data = xdp->data + offset; 2969 2970 if (unlikely(data < data_start || 2971 data > xdp->data_end - ETH_HLEN)) 2972 return -EINVAL; 2973 2974 if (metalen) 2975 memmove(xdp->data_meta + offset, 2976 xdp->data_meta, metalen); 2977 xdp->data_meta += offset; 2978 xdp->data = data; 2979 2980 return 0; 2981 } 2982 2983 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = { 2984 .func = bpf_xdp_adjust_head, 2985 .gpl_only = false, 2986 .ret_type = RET_INTEGER, 2987 .arg1_type = ARG_PTR_TO_CTX, 2988 .arg2_type = ARG_ANYTHING, 2989 }; 2990 2991 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset) 2992 { 2993 void *data_end = xdp->data_end + offset; 2994 2995 /* only shrinking is allowed for now. */ 2996 if (unlikely(offset >= 0)) 2997 return -EINVAL; 2998 2999 if (unlikely(data_end < xdp->data + ETH_HLEN)) 3000 return -EINVAL; 3001 3002 xdp->data_end = data_end; 3003 3004 return 0; 3005 } 3006 3007 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = { 3008 .func = bpf_xdp_adjust_tail, 3009 .gpl_only = false, 3010 .ret_type = RET_INTEGER, 3011 .arg1_type = ARG_PTR_TO_CTX, 3012 .arg2_type = ARG_ANYTHING, 3013 }; 3014 3015 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset) 3016 { 3017 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); 3018 void *meta = xdp->data_meta + offset; 3019 unsigned long metalen = xdp->data - meta; 3020 3021 if (xdp_data_meta_unsupported(xdp)) 3022 return -ENOTSUPP; 3023 if (unlikely(meta < xdp_frame_end || 3024 meta > xdp->data)) 3025 return -EINVAL; 3026 if (unlikely((metalen & (sizeof(__u32) - 1)) || 3027 (metalen > 32))) 3028 return -EACCES; 3029 3030 xdp->data_meta = meta; 3031 3032 return 0; 3033 } 3034 3035 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = { 3036 .func = bpf_xdp_adjust_meta, 3037 .gpl_only = false, 3038 .ret_type = RET_INTEGER, 3039 .arg1_type = ARG_PTR_TO_CTX, 3040 .arg2_type = ARG_ANYTHING, 3041 }; 3042 3043 static int __bpf_tx_xdp(struct net_device *dev, 3044 struct bpf_map *map, 3045 struct xdp_buff *xdp, 3046 u32 index) 3047 { 3048 struct xdp_frame *xdpf; 3049 int sent; 3050 3051 if (!dev->netdev_ops->ndo_xdp_xmit) { 3052 return -EOPNOTSUPP; 3053 } 3054 3055 xdpf = convert_to_xdp_frame(xdp); 3056 if (unlikely(!xdpf)) 3057 return -EOVERFLOW; 3058 3059 sent = dev->netdev_ops->ndo_xdp_xmit(dev, 1, &xdpf, XDP_XMIT_FLUSH); 3060 if (sent <= 0) 3061 return sent; 3062 return 0; 3063 } 3064 3065 static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, 3066 struct bpf_map *map, 3067 struct xdp_buff *xdp, 3068 u32 index) 3069 { 3070 int err; 3071 3072 switch (map->map_type) { 3073 case BPF_MAP_TYPE_DEVMAP: { 3074 struct bpf_dtab_netdev *dst = fwd; 3075 3076 err = dev_map_enqueue(dst, xdp, dev_rx); 3077 if (err) 3078 return err; 3079 __dev_map_insert_ctx(map, index); 3080 break; 3081 } 3082 case BPF_MAP_TYPE_CPUMAP: { 3083 struct bpf_cpu_map_entry *rcpu = fwd; 3084 3085 err = cpu_map_enqueue(rcpu, xdp, dev_rx); 3086 if (err) 3087 return err; 3088 __cpu_map_insert_ctx(map, index); 3089 break; 3090 } 3091 case BPF_MAP_TYPE_XSKMAP: { 3092 struct xdp_sock *xs = fwd; 3093 3094 err = __xsk_map_redirect(map, xdp, xs); 3095 return err; 3096 } 3097 default: 3098 break; 3099 } 3100 return 0; 3101 } 3102 3103 void xdp_do_flush_map(void) 3104 { 3105 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3106 struct bpf_map *map = ri->map_to_flush; 3107 3108 ri->map_to_flush = NULL; 3109 if (map) { 3110 switch (map->map_type) { 3111 case BPF_MAP_TYPE_DEVMAP: 3112 __dev_map_flush(map); 3113 break; 3114 case BPF_MAP_TYPE_CPUMAP: 3115 __cpu_map_flush(map); 3116 break; 3117 case BPF_MAP_TYPE_XSKMAP: 3118 __xsk_map_flush(map); 3119 break; 3120 default: 3121 break; 3122 } 3123 } 3124 } 3125 EXPORT_SYMBOL_GPL(xdp_do_flush_map); 3126 3127 static void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index) 3128 { 3129 switch (map->map_type) { 3130 case BPF_MAP_TYPE_DEVMAP: 3131 return __dev_map_lookup_elem(map, index); 3132 case BPF_MAP_TYPE_CPUMAP: 3133 return __cpu_map_lookup_elem(map, index); 3134 case BPF_MAP_TYPE_XSKMAP: 3135 return __xsk_map_lookup_elem(map, index); 3136 default: 3137 return NULL; 3138 } 3139 } 3140 3141 static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog, 3142 unsigned long aux) 3143 { 3144 return (unsigned long)xdp_prog->aux != aux; 3145 } 3146 3147 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, 3148 struct bpf_prog *xdp_prog) 3149 { 3150 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3151 unsigned long map_owner = ri->map_owner; 3152 struct bpf_map *map = ri->map; 3153 u32 index = ri->ifindex; 3154 void *fwd = NULL; 3155 int err; 3156 3157 ri->ifindex = 0; 3158 ri->map = NULL; 3159 ri->map_owner = 0; 3160 3161 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) { 3162 err = -EFAULT; 3163 map = NULL; 3164 goto err; 3165 } 3166 3167 fwd = __xdp_map_lookup_elem(map, index); 3168 if (!fwd) { 3169 err = -EINVAL; 3170 goto err; 3171 } 3172 if (ri->map_to_flush && ri->map_to_flush != map) 3173 xdp_do_flush_map(); 3174 3175 err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index); 3176 if (unlikely(err)) 3177 goto err; 3178 3179 ri->map_to_flush = map; 3180 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); 3181 return 0; 3182 err: 3183 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); 3184 return err; 3185 } 3186 3187 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, 3188 struct bpf_prog *xdp_prog) 3189 { 3190 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3191 struct net_device *fwd; 3192 u32 index = ri->ifindex; 3193 int err; 3194 3195 if (ri->map) 3196 return xdp_do_redirect_map(dev, xdp, xdp_prog); 3197 3198 fwd = dev_get_by_index_rcu(dev_net(dev), index); 3199 ri->ifindex = 0; 3200 if (unlikely(!fwd)) { 3201 err = -EINVAL; 3202 goto err; 3203 } 3204 3205 err = __bpf_tx_xdp(fwd, NULL, xdp, 0); 3206 if (unlikely(err)) 3207 goto err; 3208 3209 _trace_xdp_redirect(dev, xdp_prog, index); 3210 return 0; 3211 err: 3212 _trace_xdp_redirect_err(dev, xdp_prog, index, err); 3213 return err; 3214 } 3215 EXPORT_SYMBOL_GPL(xdp_do_redirect); 3216 3217 static int xdp_do_generic_redirect_map(struct net_device *dev, 3218 struct sk_buff *skb, 3219 struct xdp_buff *xdp, 3220 struct bpf_prog *xdp_prog) 3221 { 3222 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3223 unsigned long map_owner = ri->map_owner; 3224 struct bpf_map *map = ri->map; 3225 u32 index = ri->ifindex; 3226 void *fwd = NULL; 3227 int err = 0; 3228 3229 ri->ifindex = 0; 3230 ri->map = NULL; 3231 ri->map_owner = 0; 3232 3233 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) { 3234 err = -EFAULT; 3235 map = NULL; 3236 goto err; 3237 } 3238 fwd = __xdp_map_lookup_elem(map, index); 3239 if (unlikely(!fwd)) { 3240 err = -EINVAL; 3241 goto err; 3242 } 3243 3244 if (map->map_type == BPF_MAP_TYPE_DEVMAP) { 3245 struct bpf_dtab_netdev *dst = fwd; 3246 3247 err = dev_map_generic_redirect(dst, skb, xdp_prog); 3248 if (unlikely(err)) 3249 goto err; 3250 } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) { 3251 struct xdp_sock *xs = fwd; 3252 3253 err = xsk_generic_rcv(xs, xdp); 3254 if (err) 3255 goto err; 3256 consume_skb(skb); 3257 } else { 3258 /* TODO: Handle BPF_MAP_TYPE_CPUMAP */ 3259 err = -EBADRQC; 3260 goto err; 3261 } 3262 3263 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); 3264 return 0; 3265 err: 3266 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); 3267 return err; 3268 } 3269 3270 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, 3271 struct xdp_buff *xdp, struct bpf_prog *xdp_prog) 3272 { 3273 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3274 u32 index = ri->ifindex; 3275 struct net_device *fwd; 3276 int err = 0; 3277 3278 if (ri->map) 3279 return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog); 3280 3281 ri->ifindex = 0; 3282 fwd = dev_get_by_index_rcu(dev_net(dev), index); 3283 if (unlikely(!fwd)) { 3284 err = -EINVAL; 3285 goto err; 3286 } 3287 3288 if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd)))) 3289 goto err; 3290 3291 skb->dev = fwd; 3292 _trace_xdp_redirect(dev, xdp_prog, index); 3293 generic_xdp_tx(skb, xdp_prog); 3294 return 0; 3295 err: 3296 _trace_xdp_redirect_err(dev, xdp_prog, index, err); 3297 return err; 3298 } 3299 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect); 3300 3301 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags) 3302 { 3303 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3304 3305 if (unlikely(flags)) 3306 return XDP_ABORTED; 3307 3308 ri->ifindex = ifindex; 3309 ri->flags = flags; 3310 ri->map = NULL; 3311 ri->map_owner = 0; 3312 3313 return XDP_REDIRECT; 3314 } 3315 3316 static const struct bpf_func_proto bpf_xdp_redirect_proto = { 3317 .func = bpf_xdp_redirect, 3318 .gpl_only = false, 3319 .ret_type = RET_INTEGER, 3320 .arg1_type = ARG_ANYTHING, 3321 .arg2_type = ARG_ANYTHING, 3322 }; 3323 3324 BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags, 3325 unsigned long, map_owner) 3326 { 3327 struct redirect_info *ri = this_cpu_ptr(&redirect_info); 3328 3329 if (unlikely(flags)) 3330 return XDP_ABORTED; 3331 3332 ri->ifindex = ifindex; 3333 ri->flags = flags; 3334 ri->map = map; 3335 ri->map_owner = map_owner; 3336 3337 return XDP_REDIRECT; 3338 } 3339 3340 /* Note, arg4 is hidden from users and populated by the verifier 3341 * with the right pointer. 3342 */ 3343 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = { 3344 .func = bpf_xdp_redirect_map, 3345 .gpl_only = false, 3346 .ret_type = RET_INTEGER, 3347 .arg1_type = ARG_CONST_MAP_PTR, 3348 .arg2_type = ARG_ANYTHING, 3349 .arg3_type = ARG_ANYTHING, 3350 }; 3351 3352 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb, 3353 unsigned long off, unsigned long len) 3354 { 3355 void *ptr = skb_header_pointer(skb, off, len, dst_buff); 3356 3357 if (unlikely(!ptr)) 3358 return len; 3359 if (ptr != dst_buff) 3360 memcpy(dst_buff, ptr, len); 3361 3362 return 0; 3363 } 3364 3365 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map, 3366 u64, flags, void *, meta, u64, meta_size) 3367 { 3368 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32; 3369 3370 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) 3371 return -EINVAL; 3372 if (unlikely(skb_size > skb->len)) 3373 return -EFAULT; 3374 3375 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size, 3376 bpf_skb_copy); 3377 } 3378 3379 static const struct bpf_func_proto bpf_skb_event_output_proto = { 3380 .func = bpf_skb_event_output, 3381 .gpl_only = true, 3382 .ret_type = RET_INTEGER, 3383 .arg1_type = ARG_PTR_TO_CTX, 3384 .arg2_type = ARG_CONST_MAP_PTR, 3385 .arg3_type = ARG_ANYTHING, 3386 .arg4_type = ARG_PTR_TO_MEM, 3387 .arg5_type = ARG_CONST_SIZE_OR_ZERO, 3388 }; 3389 3390 static unsigned short bpf_tunnel_key_af(u64 flags) 3391 { 3392 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET; 3393 } 3394 3395 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to, 3396 u32, size, u64, flags) 3397 { 3398 const struct ip_tunnel_info *info = skb_tunnel_info(skb); 3399 u8 compat[sizeof(struct bpf_tunnel_key)]; 3400 void *to_orig = to; 3401 int err; 3402 3403 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) { 3404 err = -EINVAL; 3405 goto err_clear; 3406 } 3407 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) { 3408 err = -EPROTO; 3409 goto err_clear; 3410 } 3411 if (unlikely(size != sizeof(struct bpf_tunnel_key))) { 3412 err = -EINVAL; 3413 switch (size) { 3414 case offsetof(struct bpf_tunnel_key, tunnel_label): 3415 case offsetof(struct bpf_tunnel_key, tunnel_ext): 3416 goto set_compat; 3417 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): 3418 /* Fixup deprecated structure layouts here, so we have 3419 * a common path later on. 3420 */ 3421 if (ip_tunnel_info_af(info) != AF_INET) 3422 goto err_clear; 3423 set_compat: 3424 to = (struct bpf_tunnel_key *)compat; 3425 break; 3426 default: 3427 goto err_clear; 3428 } 3429 } 3430 3431 to->tunnel_id = be64_to_cpu(info->key.tun_id); 3432 to->tunnel_tos = info->key.tos; 3433 to->tunnel_ttl = info->key.ttl; 3434 to->tunnel_ext = 0; 3435 3436 if (flags & BPF_F_TUNINFO_IPV6) { 3437 memcpy(to->remote_ipv6, &info->key.u.ipv6.src, 3438 sizeof(to->remote_ipv6)); 3439 to->tunnel_label = be32_to_cpu(info->key.label); 3440 } else { 3441 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src); 3442 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3); 3443 to->tunnel_label = 0; 3444 } 3445 3446 if (unlikely(size != sizeof(struct bpf_tunnel_key))) 3447 memcpy(to_orig, to, size); 3448 3449 return 0; 3450 err_clear: 3451 memset(to_orig, 0, size); 3452 return err; 3453 } 3454 3455 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = { 3456 .func = bpf_skb_get_tunnel_key, 3457 .gpl_only = false, 3458 .ret_type = RET_INTEGER, 3459 .arg1_type = ARG_PTR_TO_CTX, 3460 .arg2_type = ARG_PTR_TO_UNINIT_MEM, 3461 .arg3_type = ARG_CONST_SIZE, 3462 .arg4_type = ARG_ANYTHING, 3463 }; 3464 3465 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size) 3466 { 3467 const struct ip_tunnel_info *info = skb_tunnel_info(skb); 3468 int err; 3469 3470 if (unlikely(!info || 3471 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) { 3472 err = -ENOENT; 3473 goto err_clear; 3474 } 3475 if (unlikely(size < info->options_len)) { 3476 err = -ENOMEM; 3477 goto err_clear; 3478 } 3479 3480 ip_tunnel_info_opts_get(to, info); 3481 if (size > info->options_len) 3482 memset(to + info->options_len, 0, size - info->options_len); 3483 3484 return info->options_len; 3485 err_clear: 3486 memset(to, 0, size); 3487 return err; 3488 } 3489 3490 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = { 3491 .func = bpf_skb_get_tunnel_opt, 3492 .gpl_only = false, 3493 .ret_type = RET_INTEGER, 3494 .arg1_type = ARG_PTR_TO_CTX, 3495 .arg2_type = ARG_PTR_TO_UNINIT_MEM, 3496 .arg3_type = ARG_CONST_SIZE, 3497 }; 3498 3499 static struct metadata_dst __percpu *md_dst; 3500 3501 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb, 3502 const struct bpf_tunnel_key *, from, u32, size, u64, flags) 3503 { 3504 struct metadata_dst *md = this_cpu_ptr(md_dst); 3505 u8 compat[sizeof(struct bpf_tunnel_key)]; 3506 struct ip_tunnel_info *info; 3507 3508 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX | 3509 BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER))) 3510 return -EINVAL; 3511 if (unlikely(size != sizeof(struct bpf_tunnel_key))) { 3512 switch (size) { 3513 case offsetof(struct bpf_tunnel_key, tunnel_label): 3514 case offsetof(struct bpf_tunnel_key, tunnel_ext): 3515 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): 3516 /* Fixup deprecated structure layouts here, so we have 3517 * a common path later on. 3518 */ 3519 memcpy(compat, from, size); 3520 memset(compat + size, 0, sizeof(compat) - size); 3521 from = (const struct bpf_tunnel_key *) compat; 3522 break; 3523 default: 3524 return -EINVAL; 3525 } 3526 } 3527 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) || 3528 from->tunnel_ext)) 3529 return -EINVAL; 3530 3531 skb_dst_drop(skb); 3532 dst_hold((struct dst_entry *) md); 3533 skb_dst_set(skb, (struct dst_entry *) md); 3534 3535 info = &md->u.tun_info; 3536 memset(info, 0, sizeof(*info)); 3537 info->mode = IP_TUNNEL_INFO_TX; 3538 3539 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE; 3540 if (flags & BPF_F_DONT_FRAGMENT) 3541 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT; 3542 if (flags & BPF_F_ZERO_CSUM_TX) 3543 info->key.tun_flags &= ~TUNNEL_CSUM; 3544 if (flags & BPF_F_SEQ_NUMBER) 3545 info->key.tun_flags |= TUNNEL_SEQ; 3546 3547 info->key.tun_id = cpu_to_be64(from->tunnel_id); 3548 info->key.tos = from->tunnel_tos; 3549 info->key.ttl = from->tunnel_ttl; 3550 3551 if (flags & BPF_F_TUNINFO_IPV6) { 3552 info->mode |= IP_TUNNEL_INFO_IPV6; 3553 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6, 3554 sizeof(from->remote_ipv6)); 3555 info->key.label = cpu_to_be32(from->tunnel_label) & 3556 IPV6_FLOWLABEL_MASK; 3557 } else { 3558 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4); 3559 } 3560 3561 return 0; 3562 } 3563 3564 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = { 3565 .func = bpf_skb_set_tunnel_key, 3566 .gpl_only = false, 3567 .ret_type = RET_INTEGER, 3568 .arg1_type = ARG_PTR_TO_CTX, 3569 .arg2_type = ARG_PTR_TO_MEM, 3570 .arg3_type = ARG_CONST_SIZE, 3571 .arg4_type = ARG_ANYTHING, 3572 }; 3573 3574 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb, 3575 const u8 *, from, u32, size) 3576 { 3577 struct ip_tunnel_info *info = skb_tunnel_info(skb); 3578 const struct metadata_dst *md = this_cpu_ptr(md_dst); 3579 3580 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1)))) 3581 return -EINVAL; 3582 if (unlikely(size > IP_TUNNEL_OPTS_MAX)) 3583 return -ENOMEM; 3584 3585 ip_tunnel_info_opts_set(info, from, size); 3586 3587 return 0; 3588 } 3589 3590 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = { 3591 .func = bpf_skb_set_tunnel_opt, 3592 .gpl_only = false, 3593 .ret_type = RET_INTEGER, 3594 .arg1_type = ARG_PTR_TO_CTX, 3595 .arg2_type = ARG_PTR_TO_MEM, 3596 .arg3_type = ARG_CONST_SIZE, 3597 }; 3598 3599 static const struct bpf_func_proto * 3600 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which) 3601 { 3602 if (!md_dst) { 3603 struct metadata_dst __percpu *tmp; 3604 3605 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX, 3606 METADATA_IP_TUNNEL, 3607 GFP_KERNEL); 3608 if (!tmp) 3609 return NULL; 3610 if (cmpxchg(&md_dst, NULL, tmp)) 3611 metadata_dst_free_percpu(tmp); 3612 } 3613 3614 switch (which) { 3615 case BPF_FUNC_skb_set_tunnel_key: 3616 return &bpf_skb_set_tunnel_key_proto; 3617 case BPF_FUNC_skb_set_tunnel_opt: 3618 return &bpf_skb_set_tunnel_opt_proto; 3619 default: 3620 return NULL; 3621 } 3622 } 3623 3624 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map, 3625 u32, idx) 3626 { 3627 struct bpf_array *array = container_of(map, struct bpf_array, map); 3628 struct cgroup *cgrp; 3629 struct sock *sk; 3630 3631 sk = skb_to_full_sk(skb); 3632 if (!sk || !sk_fullsock(sk)) 3633 return -ENOENT; 3634 if (unlikely(idx >= array->map.max_entries)) 3635 return -E2BIG; 3636 3637 cgrp = READ_ONCE(array->ptrs[idx]); 3638 if (unlikely(!cgrp)) 3639 return -EAGAIN; 3640 3641 return sk_under_cgroup_hierarchy(sk, cgrp); 3642 } 3643 3644 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = { 3645 .func = bpf_skb_under_cgroup, 3646 .gpl_only = false, 3647 .ret_type = RET_INTEGER, 3648 .arg1_type = ARG_PTR_TO_CTX, 3649 .arg2_type = ARG_CONST_MAP_PTR, 3650 .arg3_type = ARG_ANYTHING, 3651 }; 3652 3653 #ifdef CONFIG_SOCK_CGROUP_DATA 3654 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb) 3655 { 3656 struct sock *sk = skb_to_full_sk(skb); 3657 struct cgroup *cgrp; 3658 3659 if (!sk || !sk_fullsock(sk)) 3660 return 0; 3661 3662 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data); 3663 return cgrp->kn->id.id; 3664 } 3665 3666 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = { 3667 .func = bpf_skb_cgroup_id, 3668 .gpl_only = false, 3669 .ret_type = RET_INTEGER, 3670 .arg1_type = ARG_PTR_TO_CTX, 3671 }; 3672 #endif 3673 3674 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff, 3675 unsigned long off, unsigned long len) 3676 { 3677 memcpy(dst_buff, src_buff + off, len); 3678 return 0; 3679 } 3680 3681 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map, 3682 u64, flags, void *, meta, u64, meta_size) 3683 { 3684 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32; 3685 3686 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) 3687 return -EINVAL; 3688 if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data))) 3689 return -EFAULT; 3690 3691 return bpf_event_output(map, flags, meta, meta_size, xdp->data, 3692 xdp_size, bpf_xdp_copy); 3693 } 3694 3695 static const struct bpf_func_proto bpf_xdp_event_output_proto = { 3696 .func = bpf_xdp_event_output, 3697 .gpl_only = true, 3698 .ret_type = RET_INTEGER, 3699 .arg1_type = ARG_PTR_TO_CTX, 3700 .arg2_type = ARG_CONST_MAP_PTR, 3701 .arg3_type = ARG_ANYTHING, 3702 .arg4_type = ARG_PTR_TO_MEM, 3703 .arg5_type = ARG_CONST_SIZE_OR_ZERO, 3704 }; 3705 3706 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb) 3707 { 3708 return skb->sk ? sock_gen_cookie(skb->sk) : 0; 3709 } 3710 3711 static const struct bpf_func_proto bpf_get_socket_cookie_proto = { 3712 .func = bpf_get_socket_cookie, 3713 .gpl_only = false, 3714 .ret_type = RET_INTEGER, 3715 .arg1_type = ARG_PTR_TO_CTX, 3716 }; 3717 3718 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb) 3719 { 3720 struct sock *sk = sk_to_full_sk(skb->sk); 3721 kuid_t kuid; 3722 3723 if (!sk || !sk_fullsock(sk)) 3724 return overflowuid; 3725 kuid = sock_net_uid(sock_net(sk), sk); 3726 return from_kuid_munged(sock_net(sk)->user_ns, kuid); 3727 } 3728 3729 static const struct bpf_func_proto bpf_get_socket_uid_proto = { 3730 .func = bpf_get_socket_uid, 3731 .gpl_only = false, 3732 .ret_type = RET_INTEGER, 3733 .arg1_type = ARG_PTR_TO_CTX, 3734 }; 3735 3736 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, 3737 int, level, int, optname, char *, optval, int, optlen) 3738 { 3739 struct sock *sk = bpf_sock->sk; 3740 int ret = 0; 3741 int val; 3742 3743 if (!sk_fullsock(sk)) 3744 return -EINVAL; 3745 3746 if (level == SOL_SOCKET) { 3747 if (optlen != sizeof(int)) 3748 return -EINVAL; 3749 val = *((int *)optval); 3750 3751 /* Only some socketops are supported */ 3752 switch (optname) { 3753 case SO_RCVBUF: 3754 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 3755 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF); 3756 break; 3757 case SO_SNDBUF: 3758 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 3759 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF); 3760 break; 3761 case SO_MAX_PACING_RATE: 3762 sk->sk_max_pacing_rate = val; 3763 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 3764 sk->sk_max_pacing_rate); 3765 break; 3766 case SO_PRIORITY: 3767 sk->sk_priority = val; 3768 break; 3769 case SO_RCVLOWAT: 3770 if (val < 0) 3771 val = INT_MAX; 3772 sk->sk_rcvlowat = val ? : 1; 3773 break; 3774 case SO_MARK: 3775 sk->sk_mark = val; 3776 break; 3777 default: 3778 ret = -EINVAL; 3779 } 3780 #ifdef CONFIG_INET 3781 } else if (level == SOL_IP) { 3782 if (optlen != sizeof(int) || sk->sk_family != AF_INET) 3783 return -EINVAL; 3784 3785 val = *((int *)optval); 3786 /* Only some options are supported */ 3787 switch (optname) { 3788 case IP_TOS: 3789 if (val < -1 || val > 0xff) { 3790 ret = -EINVAL; 3791 } else { 3792 struct inet_sock *inet = inet_sk(sk); 3793 3794 if (val == -1) 3795 val = 0; 3796 inet->tos = val; 3797 } 3798 break; 3799 default: 3800 ret = -EINVAL; 3801 } 3802 #if IS_ENABLED(CONFIG_IPV6) 3803 } else if (level == SOL_IPV6) { 3804 if (optlen != sizeof(int) || sk->sk_family != AF_INET6) 3805 return -EINVAL; 3806 3807 val = *((int *)optval); 3808 /* Only some options are supported */ 3809 switch (optname) { 3810 case IPV6_TCLASS: 3811 if (val < -1 || val > 0xff) { 3812 ret = -EINVAL; 3813 } else { 3814 struct ipv6_pinfo *np = inet6_sk(sk); 3815 3816 if (val == -1) 3817 val = 0; 3818 np->tclass = val; 3819 } 3820 break; 3821 default: 3822 ret = -EINVAL; 3823 } 3824 #endif 3825 } else if (level == SOL_TCP && 3826 sk->sk_prot->setsockopt == tcp_setsockopt) { 3827 if (optname == TCP_CONGESTION) { 3828 char name[TCP_CA_NAME_MAX]; 3829 bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN; 3830 3831 strncpy(name, optval, min_t(long, optlen, 3832 TCP_CA_NAME_MAX-1)); 3833 name[TCP_CA_NAME_MAX-1] = 0; 3834 ret = tcp_set_congestion_control(sk, name, false, 3835 reinit); 3836 } else { 3837 struct tcp_sock *tp = tcp_sk(sk); 3838 3839 if (optlen != sizeof(int)) 3840 return -EINVAL; 3841 3842 val = *((int *)optval); 3843 /* Only some options are supported */ 3844 switch (optname) { 3845 case TCP_BPF_IW: 3846 if (val <= 0 || tp->data_segs_out > 0) 3847 ret = -EINVAL; 3848 else 3849 tp->snd_cwnd = val; 3850 break; 3851 case TCP_BPF_SNDCWND_CLAMP: 3852 if (val <= 0) { 3853 ret = -EINVAL; 3854 } else { 3855 tp->snd_cwnd_clamp = val; 3856 tp->snd_ssthresh = val; 3857 } 3858 break; 3859 default: 3860 ret = -EINVAL; 3861 } 3862 } 3863 #endif 3864 } else { 3865 ret = -EINVAL; 3866 } 3867 return ret; 3868 } 3869 3870 static const struct bpf_func_proto bpf_setsockopt_proto = { 3871 .func = bpf_setsockopt, 3872 .gpl_only = false, 3873 .ret_type = RET_INTEGER, 3874 .arg1_type = ARG_PTR_TO_CTX, 3875 .arg2_type = ARG_ANYTHING, 3876 .arg3_type = ARG_ANYTHING, 3877 .arg4_type = ARG_PTR_TO_MEM, 3878 .arg5_type = ARG_CONST_SIZE, 3879 }; 3880 3881 BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock, 3882 int, level, int, optname, char *, optval, int, optlen) 3883 { 3884 struct sock *sk = bpf_sock->sk; 3885 3886 if (!sk_fullsock(sk)) 3887 goto err_clear; 3888 3889 #ifdef CONFIG_INET 3890 if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) { 3891 if (optname == TCP_CONGESTION) { 3892 struct inet_connection_sock *icsk = inet_csk(sk); 3893 3894 if (!icsk->icsk_ca_ops || optlen <= 1) 3895 goto err_clear; 3896 strncpy(optval, icsk->icsk_ca_ops->name, optlen); 3897 optval[optlen - 1] = 0; 3898 } else { 3899 goto err_clear; 3900 } 3901 } else if (level == SOL_IP) { 3902 struct inet_sock *inet = inet_sk(sk); 3903 3904 if (optlen != sizeof(int) || sk->sk_family != AF_INET) 3905 goto err_clear; 3906 3907 /* Only some options are supported */ 3908 switch (optname) { 3909 case IP_TOS: 3910 *((int *)optval) = (int)inet->tos; 3911 break; 3912 default: 3913 goto err_clear; 3914 } 3915 #if IS_ENABLED(CONFIG_IPV6) 3916 } else if (level == SOL_IPV6) { 3917 struct ipv6_pinfo *np = inet6_sk(sk); 3918 3919 if (optlen != sizeof(int) || sk->sk_family != AF_INET6) 3920 goto err_clear; 3921 3922 /* Only some options are supported */ 3923 switch (optname) { 3924 case IPV6_TCLASS: 3925 *((int *)optval) = (int)np->tclass; 3926 break; 3927 default: 3928 goto err_clear; 3929 } 3930 #endif 3931 } else { 3932 goto err_clear; 3933 } 3934 return 0; 3935 #endif 3936 err_clear: 3937 memset(optval, 0, optlen); 3938 return -EINVAL; 3939 } 3940 3941 static const struct bpf_func_proto bpf_getsockopt_proto = { 3942 .func = bpf_getsockopt, 3943 .gpl_only = false, 3944 .ret_type = RET_INTEGER, 3945 .arg1_type = ARG_PTR_TO_CTX, 3946 .arg2_type = ARG_ANYTHING, 3947 .arg3_type = ARG_ANYTHING, 3948 .arg4_type = ARG_PTR_TO_UNINIT_MEM, 3949 .arg5_type = ARG_CONST_SIZE, 3950 }; 3951 3952 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock, 3953 int, argval) 3954 { 3955 struct sock *sk = bpf_sock->sk; 3956 int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS; 3957 3958 if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk)) 3959 return -EINVAL; 3960 3961 if (val) 3962 tcp_sk(sk)->bpf_sock_ops_cb_flags = val; 3963 3964 return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS); 3965 } 3966 3967 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = { 3968 .func = bpf_sock_ops_cb_flags_set, 3969 .gpl_only = false, 3970 .ret_type = RET_INTEGER, 3971 .arg1_type = ARG_PTR_TO_CTX, 3972 .arg2_type = ARG_ANYTHING, 3973 }; 3974 3975 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly; 3976 EXPORT_SYMBOL_GPL(ipv6_bpf_stub); 3977 3978 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr, 3979 int, addr_len) 3980 { 3981 #ifdef CONFIG_INET 3982 struct sock *sk = ctx->sk; 3983 int err; 3984 3985 /* Binding to port can be expensive so it's prohibited in the helper. 3986 * Only binding to IP is supported. 3987 */ 3988 err = -EINVAL; 3989 if (addr->sa_family == AF_INET) { 3990 if (addr_len < sizeof(struct sockaddr_in)) 3991 return err; 3992 if (((struct sockaddr_in *)addr)->sin_port != htons(0)) 3993 return err; 3994 return __inet_bind(sk, addr, addr_len, true, false); 3995 #if IS_ENABLED(CONFIG_IPV6) 3996 } else if (addr->sa_family == AF_INET6) { 3997 if (addr_len < SIN6_LEN_RFC2133) 3998 return err; 3999 if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0)) 4000 return err; 4001 /* ipv6_bpf_stub cannot be NULL, since it's called from 4002 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded 4003 */ 4004 return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, true, false); 4005 #endif /* CONFIG_IPV6 */ 4006 } 4007 #endif /* CONFIG_INET */ 4008 4009 return -EAFNOSUPPORT; 4010 } 4011 4012 static const struct bpf_func_proto bpf_bind_proto = { 4013 .func = bpf_bind, 4014 .gpl_only = false, 4015 .ret_type = RET_INTEGER, 4016 .arg1_type = ARG_PTR_TO_CTX, 4017 .arg2_type = ARG_PTR_TO_MEM, 4018 .arg3_type = ARG_CONST_SIZE, 4019 }; 4020 4021 #ifdef CONFIG_XFRM 4022 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index, 4023 struct bpf_xfrm_state *, to, u32, size, u64, flags) 4024 { 4025 const struct sec_path *sp = skb_sec_path(skb); 4026 const struct xfrm_state *x; 4027 4028 if (!sp || unlikely(index >= sp->len || flags)) 4029 goto err_clear; 4030 4031 x = sp->xvec[index]; 4032 4033 if (unlikely(size != sizeof(struct bpf_xfrm_state))) 4034 goto err_clear; 4035 4036 to->reqid = x->props.reqid; 4037 to->spi = x->id.spi; 4038 to->family = x->props.family; 4039 to->ext = 0; 4040 4041 if (to->family == AF_INET6) { 4042 memcpy(to->remote_ipv6, x->props.saddr.a6, 4043 sizeof(to->remote_ipv6)); 4044 } else { 4045 to->remote_ipv4 = x->props.saddr.a4; 4046 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3); 4047 } 4048 4049 return 0; 4050 err_clear: 4051 memset(to, 0, size); 4052 return -EINVAL; 4053 } 4054 4055 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = { 4056 .func = bpf_skb_get_xfrm_state, 4057 .gpl_only = false, 4058 .ret_type = RET_INTEGER, 4059 .arg1_type = ARG_PTR_TO_CTX, 4060 .arg2_type = ARG_ANYTHING, 4061 .arg3_type = ARG_PTR_TO_UNINIT_MEM, 4062 .arg4_type = ARG_CONST_SIZE, 4063 .arg5_type = ARG_ANYTHING, 4064 }; 4065 #endif 4066 4067 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6) 4068 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, 4069 const struct neighbour *neigh, 4070 const struct net_device *dev) 4071 { 4072 memcpy(params->dmac, neigh->ha, ETH_ALEN); 4073 memcpy(params->smac, dev->dev_addr, ETH_ALEN); 4074 params->h_vlan_TCI = 0; 4075 params->h_vlan_proto = 0; 4076 4077 return dev->ifindex; 4078 } 4079 #endif 4080 4081 #if IS_ENABLED(CONFIG_INET) 4082 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, 4083 u32 flags, bool check_mtu) 4084 { 4085 struct in_device *in_dev; 4086 struct neighbour *neigh; 4087 struct net_device *dev; 4088 struct fib_result res; 4089 struct fib_nh *nh; 4090 struct flowi4 fl4; 4091 int err; 4092 u32 mtu; 4093 4094 dev = dev_get_by_index_rcu(net, params->ifindex); 4095 if (unlikely(!dev)) 4096 return -ENODEV; 4097 4098 /* verify forwarding is enabled on this interface */ 4099 in_dev = __in_dev_get_rcu(dev); 4100 if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev))) 4101 return 0; 4102 4103 if (flags & BPF_FIB_LOOKUP_OUTPUT) { 4104 fl4.flowi4_iif = 1; 4105 fl4.flowi4_oif = params->ifindex; 4106 } else { 4107 fl4.flowi4_iif = params->ifindex; 4108 fl4.flowi4_oif = 0; 4109 } 4110 fl4.flowi4_tos = params->tos & IPTOS_RT_MASK; 4111 fl4.flowi4_scope = RT_SCOPE_UNIVERSE; 4112 fl4.flowi4_flags = 0; 4113 4114 fl4.flowi4_proto = params->l4_protocol; 4115 fl4.daddr = params->ipv4_dst; 4116 fl4.saddr = params->ipv4_src; 4117 fl4.fl4_sport = params->sport; 4118 fl4.fl4_dport = params->dport; 4119 4120 if (flags & BPF_FIB_LOOKUP_DIRECT) { 4121 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN; 4122 struct fib_table *tb; 4123 4124 tb = fib_get_table(net, tbid); 4125 if (unlikely(!tb)) 4126 return 0; 4127 4128 err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); 4129 } else { 4130 fl4.flowi4_mark = 0; 4131 fl4.flowi4_secid = 0; 4132 fl4.flowi4_tun_key.tun_id = 0; 4133 fl4.flowi4_uid = sock_net_uid(net, NULL); 4134 4135 err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF); 4136 } 4137 4138 if (err || res.type != RTN_UNICAST) 4139 return 0; 4140 4141 if (res.fi->fib_nhs > 1) 4142 fib_select_path(net, &res, &fl4, NULL); 4143 4144 if (check_mtu) { 4145 mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst); 4146 if (params->tot_len > mtu) 4147 return 0; 4148 } 4149 4150 nh = &res.fi->fib_nh[res.nh_sel]; 4151 4152 /* do not handle lwt encaps right now */ 4153 if (nh->nh_lwtstate) 4154 return 0; 4155 4156 dev = nh->nh_dev; 4157 if (unlikely(!dev)) 4158 return 0; 4159 4160 if (nh->nh_gw) 4161 params->ipv4_dst = nh->nh_gw; 4162 4163 params->rt_metric = res.fi->fib_priority; 4164 4165 /* xdp and cls_bpf programs are run in RCU-bh so 4166 * rcu_read_lock_bh is not needed here 4167 */ 4168 neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)params->ipv4_dst); 4169 if (neigh) 4170 return bpf_fib_set_fwd_params(params, neigh, dev); 4171 4172 return 0; 4173 } 4174 #endif 4175 4176 #if IS_ENABLED(CONFIG_IPV6) 4177 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, 4178 u32 flags, bool check_mtu) 4179 { 4180 struct in6_addr *src = (struct in6_addr *) params->ipv6_src; 4181 struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst; 4182 struct neighbour *neigh; 4183 struct net_device *dev; 4184 struct inet6_dev *idev; 4185 struct fib6_info *f6i; 4186 struct flowi6 fl6; 4187 int strict = 0; 4188 int oif; 4189 u32 mtu; 4190 4191 /* link local addresses are never forwarded */ 4192 if (rt6_need_strict(dst) || rt6_need_strict(src)) 4193 return 0; 4194 4195 dev = dev_get_by_index_rcu(net, params->ifindex); 4196 if (unlikely(!dev)) 4197 return -ENODEV; 4198 4199 idev = __in6_dev_get_safely(dev); 4200 if (unlikely(!idev || !net->ipv6.devconf_all->forwarding)) 4201 return 0; 4202 4203 if (flags & BPF_FIB_LOOKUP_OUTPUT) { 4204 fl6.flowi6_iif = 1; 4205 oif = fl6.flowi6_oif = params->ifindex; 4206 } else { 4207 oif = fl6.flowi6_iif = params->ifindex; 4208 fl6.flowi6_oif = 0; 4209 strict = RT6_LOOKUP_F_HAS_SADDR; 4210 } 4211 fl6.flowlabel = params->flowinfo; 4212 fl6.flowi6_scope = 0; 4213 fl6.flowi6_flags = 0; 4214 fl6.mp_hash = 0; 4215 4216 fl6.flowi6_proto = params->l4_protocol; 4217 fl6.daddr = *dst; 4218 fl6.saddr = *src; 4219 fl6.fl6_sport = params->sport; 4220 fl6.fl6_dport = params->dport; 4221 4222 if (flags & BPF_FIB_LOOKUP_DIRECT) { 4223 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN; 4224 struct fib6_table *tb; 4225 4226 tb = ipv6_stub->fib6_get_table(net, tbid); 4227 if (unlikely(!tb)) 4228 return 0; 4229 4230 f6i = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, strict); 4231 } else { 4232 fl6.flowi6_mark = 0; 4233 fl6.flowi6_secid = 0; 4234 fl6.flowi6_tun_key.tun_id = 0; 4235 fl6.flowi6_uid = sock_net_uid(net, NULL); 4236 4237 f6i = ipv6_stub->fib6_lookup(net, oif, &fl6, strict); 4238 } 4239 4240 if (unlikely(IS_ERR_OR_NULL(f6i) || f6i == net->ipv6.fib6_null_entry)) 4241 return 0; 4242 4243 if (unlikely(f6i->fib6_flags & RTF_REJECT || 4244 f6i->fib6_type != RTN_UNICAST)) 4245 return 0; 4246 4247 if (f6i->fib6_nsiblings && fl6.flowi6_oif == 0) 4248 f6i = ipv6_stub->fib6_multipath_select(net, f6i, &fl6, 4249 fl6.flowi6_oif, NULL, 4250 strict); 4251 4252 if (check_mtu) { 4253 mtu = ipv6_stub->ip6_mtu_from_fib6(f6i, dst, src); 4254 if (params->tot_len > mtu) 4255 return 0; 4256 } 4257 4258 if (f6i->fib6_nh.nh_lwtstate) 4259 return 0; 4260 4261 if (f6i->fib6_flags & RTF_GATEWAY) 4262 *dst = f6i->fib6_nh.nh_gw; 4263 4264 dev = f6i->fib6_nh.nh_dev; 4265 params->rt_metric = f6i->fib6_metric; 4266 4267 /* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is 4268 * not needed here. Can not use __ipv6_neigh_lookup_noref here 4269 * because we need to get nd_tbl via the stub 4270 */ 4271 neigh = ___neigh_lookup_noref(ipv6_stub->nd_tbl, neigh_key_eq128, 4272 ndisc_hashfn, dst, dev); 4273 if (neigh) 4274 return bpf_fib_set_fwd_params(params, neigh, dev); 4275 4276 return 0; 4277 } 4278 #endif 4279 4280 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx, 4281 struct bpf_fib_lookup *, params, int, plen, u32, flags) 4282 { 4283 if (plen < sizeof(*params)) 4284 return -EINVAL; 4285 4286 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT)) 4287 return -EINVAL; 4288 4289 switch (params->family) { 4290 #if IS_ENABLED(CONFIG_INET) 4291 case AF_INET: 4292 return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params, 4293 flags, true); 4294 #endif 4295 #if IS_ENABLED(CONFIG_IPV6) 4296 case AF_INET6: 4297 return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params, 4298 flags, true); 4299 #endif 4300 } 4301 return -EAFNOSUPPORT; 4302 } 4303 4304 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = { 4305 .func = bpf_xdp_fib_lookup, 4306 .gpl_only = true, 4307 .ret_type = RET_INTEGER, 4308 .arg1_type = ARG_PTR_TO_CTX, 4309 .arg2_type = ARG_PTR_TO_MEM, 4310 .arg3_type = ARG_CONST_SIZE, 4311 .arg4_type = ARG_ANYTHING, 4312 }; 4313 4314 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb, 4315 struct bpf_fib_lookup *, params, int, plen, u32, flags) 4316 { 4317 struct net *net = dev_net(skb->dev); 4318 int index = -EAFNOSUPPORT; 4319 4320 if (plen < sizeof(*params)) 4321 return -EINVAL; 4322 4323 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT)) 4324 return -EINVAL; 4325 4326 switch (params->family) { 4327 #if IS_ENABLED(CONFIG_INET) 4328 case AF_INET: 4329 index = bpf_ipv4_fib_lookup(net, params, flags, false); 4330 break; 4331 #endif 4332 #if IS_ENABLED(CONFIG_IPV6) 4333 case AF_INET6: 4334 index = bpf_ipv6_fib_lookup(net, params, flags, false); 4335 break; 4336 #endif 4337 } 4338 4339 if (index > 0) { 4340 struct net_device *dev; 4341 4342 dev = dev_get_by_index_rcu(net, index); 4343 if (!is_skb_forwardable(dev, skb)) 4344 index = 0; 4345 } 4346 4347 return index; 4348 } 4349 4350 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = { 4351 .func = bpf_skb_fib_lookup, 4352 .gpl_only = true, 4353 .ret_type = RET_INTEGER, 4354 .arg1_type = ARG_PTR_TO_CTX, 4355 .arg2_type = ARG_PTR_TO_MEM, 4356 .arg3_type = ARG_CONST_SIZE, 4357 .arg4_type = ARG_ANYTHING, 4358 }; 4359 4360 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4361 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len) 4362 { 4363 int err; 4364 struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr; 4365 4366 if (!seg6_validate_srh(srh, len)) 4367 return -EINVAL; 4368 4369 switch (type) { 4370 case BPF_LWT_ENCAP_SEG6_INLINE: 4371 if (skb->protocol != htons(ETH_P_IPV6)) 4372 return -EBADMSG; 4373 4374 err = seg6_do_srh_inline(skb, srh); 4375 break; 4376 case BPF_LWT_ENCAP_SEG6: 4377 skb_reset_inner_headers(skb); 4378 skb->encapsulation = 1; 4379 err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6); 4380 break; 4381 default: 4382 return -EINVAL; 4383 } 4384 4385 bpf_compute_data_pointers(skb); 4386 if (err) 4387 return err; 4388 4389 ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 4390 skb_set_transport_header(skb, sizeof(struct ipv6hdr)); 4391 4392 return seg6_lookup_nexthop(skb, NULL, 0); 4393 } 4394 #endif /* CONFIG_IPV6_SEG6_BPF */ 4395 4396 BPF_CALL_4(bpf_lwt_push_encap, struct sk_buff *, skb, u32, type, void *, hdr, 4397 u32, len) 4398 { 4399 switch (type) { 4400 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4401 case BPF_LWT_ENCAP_SEG6: 4402 case BPF_LWT_ENCAP_SEG6_INLINE: 4403 return bpf_push_seg6_encap(skb, type, hdr, len); 4404 #endif 4405 default: 4406 return -EINVAL; 4407 } 4408 } 4409 4410 static const struct bpf_func_proto bpf_lwt_push_encap_proto = { 4411 .func = bpf_lwt_push_encap, 4412 .gpl_only = false, 4413 .ret_type = RET_INTEGER, 4414 .arg1_type = ARG_PTR_TO_CTX, 4415 .arg2_type = ARG_ANYTHING, 4416 .arg3_type = ARG_PTR_TO_MEM, 4417 .arg4_type = ARG_CONST_SIZE 4418 }; 4419 4420 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset, 4421 const void *, from, u32, len) 4422 { 4423 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4424 struct seg6_bpf_srh_state *srh_state = 4425 this_cpu_ptr(&seg6_bpf_srh_states); 4426 void *srh_tlvs, *srh_end, *ptr; 4427 struct ipv6_sr_hdr *srh; 4428 int srhoff = 0; 4429 4430 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4431 return -EINVAL; 4432 4433 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4434 srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4)); 4435 srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen); 4436 4437 ptr = skb->data + offset; 4438 if (ptr >= srh_tlvs && ptr + len <= srh_end) 4439 srh_state->valid = 0; 4440 else if (ptr < (void *)&srh->flags || 4441 ptr + len > (void *)&srh->segments) 4442 return -EFAULT; 4443 4444 if (unlikely(bpf_try_make_writable(skb, offset + len))) 4445 return -EFAULT; 4446 4447 memcpy(skb->data + offset, from, len); 4448 return 0; 4449 #else /* CONFIG_IPV6_SEG6_BPF */ 4450 return -EOPNOTSUPP; 4451 #endif 4452 } 4453 4454 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = { 4455 .func = bpf_lwt_seg6_store_bytes, 4456 .gpl_only = false, 4457 .ret_type = RET_INTEGER, 4458 .arg1_type = ARG_PTR_TO_CTX, 4459 .arg2_type = ARG_ANYTHING, 4460 .arg3_type = ARG_PTR_TO_MEM, 4461 .arg4_type = ARG_CONST_SIZE 4462 }; 4463 4464 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb, 4465 u32, action, void *, param, u32, param_len) 4466 { 4467 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4468 struct seg6_bpf_srh_state *srh_state = 4469 this_cpu_ptr(&seg6_bpf_srh_states); 4470 struct ipv6_sr_hdr *srh; 4471 int srhoff = 0; 4472 int err; 4473 4474 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4475 return -EINVAL; 4476 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4477 4478 if (!srh_state->valid) { 4479 if (unlikely((srh_state->hdrlen & 7) != 0)) 4480 return -EBADMSG; 4481 4482 srh->hdrlen = (u8)(srh_state->hdrlen >> 3); 4483 if (unlikely(!seg6_validate_srh(srh, (srh->hdrlen + 1) << 3))) 4484 return -EBADMSG; 4485 4486 srh_state->valid = 1; 4487 } 4488 4489 switch (action) { 4490 case SEG6_LOCAL_ACTION_END_X: 4491 if (param_len != sizeof(struct in6_addr)) 4492 return -EINVAL; 4493 return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0); 4494 case SEG6_LOCAL_ACTION_END_T: 4495 if (param_len != sizeof(int)) 4496 return -EINVAL; 4497 return seg6_lookup_nexthop(skb, NULL, *(int *)param); 4498 case SEG6_LOCAL_ACTION_END_B6: 4499 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE, 4500 param, param_len); 4501 if (!err) 4502 srh_state->hdrlen = 4503 ((struct ipv6_sr_hdr *)param)->hdrlen << 3; 4504 return err; 4505 case SEG6_LOCAL_ACTION_END_B6_ENCAP: 4506 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6, 4507 param, param_len); 4508 if (!err) 4509 srh_state->hdrlen = 4510 ((struct ipv6_sr_hdr *)param)->hdrlen << 3; 4511 return err; 4512 default: 4513 return -EINVAL; 4514 } 4515 #else /* CONFIG_IPV6_SEG6_BPF */ 4516 return -EOPNOTSUPP; 4517 #endif 4518 } 4519 4520 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = { 4521 .func = bpf_lwt_seg6_action, 4522 .gpl_only = false, 4523 .ret_type = RET_INTEGER, 4524 .arg1_type = ARG_PTR_TO_CTX, 4525 .arg2_type = ARG_ANYTHING, 4526 .arg3_type = ARG_PTR_TO_MEM, 4527 .arg4_type = ARG_CONST_SIZE 4528 }; 4529 4530 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset, 4531 s32, len) 4532 { 4533 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF) 4534 struct seg6_bpf_srh_state *srh_state = 4535 this_cpu_ptr(&seg6_bpf_srh_states); 4536 void *srh_end, *srh_tlvs, *ptr; 4537 struct ipv6_sr_hdr *srh; 4538 struct ipv6hdr *hdr; 4539 int srhoff = 0; 4540 int ret; 4541 4542 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) 4543 return -EINVAL; 4544 srh = (struct ipv6_sr_hdr *)(skb->data + srhoff); 4545 4546 srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) + 4547 ((srh->first_segment + 1) << 4)); 4548 srh_end = (void *)((unsigned char *)srh + sizeof(*srh) + 4549 srh_state->hdrlen); 4550 ptr = skb->data + offset; 4551 4552 if (unlikely(ptr < srh_tlvs || ptr > srh_end)) 4553 return -EFAULT; 4554 if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end)) 4555 return -EFAULT; 4556 4557 if (len > 0) { 4558 ret = skb_cow_head(skb, len); 4559 if (unlikely(ret < 0)) 4560 return ret; 4561 4562 ret = bpf_skb_net_hdr_push(skb, offset, len); 4563 } else { 4564 ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len); 4565 } 4566 4567 bpf_compute_data_pointers(skb); 4568 if (unlikely(ret < 0)) 4569 return ret; 4570 4571 hdr = (struct ipv6hdr *)skb->data; 4572 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 4573 4574 srh_state->hdrlen += len; 4575 srh_state->valid = 0; 4576 return 0; 4577 #else /* CONFIG_IPV6_SEG6_BPF */ 4578 return -EOPNOTSUPP; 4579 #endif 4580 } 4581 4582 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = { 4583 .func = bpf_lwt_seg6_adjust_srh, 4584 .gpl_only = false, 4585 .ret_type = RET_INTEGER, 4586 .arg1_type = ARG_PTR_TO_CTX, 4587 .arg2_type = ARG_ANYTHING, 4588 .arg3_type = ARG_ANYTHING, 4589 }; 4590 4591 bool bpf_helper_changes_pkt_data(void *func) 4592 { 4593 if (func == bpf_skb_vlan_push || 4594 func == bpf_skb_vlan_pop || 4595 func == bpf_skb_store_bytes || 4596 func == bpf_skb_change_proto || 4597 func == bpf_skb_change_head || 4598 func == bpf_skb_change_tail || 4599 func == bpf_skb_adjust_room || 4600 func == bpf_skb_pull_data || 4601 func == bpf_clone_redirect || 4602 func == bpf_l3_csum_replace || 4603 func == bpf_l4_csum_replace || 4604 func == bpf_xdp_adjust_head || 4605 func == bpf_xdp_adjust_meta || 4606 func == bpf_msg_pull_data || 4607 func == bpf_xdp_adjust_tail || 4608 func == bpf_lwt_push_encap || 4609 func == bpf_lwt_seg6_store_bytes || 4610 func == bpf_lwt_seg6_adjust_srh || 4611 func == bpf_lwt_seg6_action 4612 ) 4613 return true; 4614 4615 return false; 4616 } 4617 4618 static const struct bpf_func_proto * 4619 bpf_base_func_proto(enum bpf_func_id func_id) 4620 { 4621 switch (func_id) { 4622 case BPF_FUNC_map_lookup_elem: 4623 return &bpf_map_lookup_elem_proto; 4624 case BPF_FUNC_map_update_elem: 4625 return &bpf_map_update_elem_proto; 4626 case BPF_FUNC_map_delete_elem: 4627 return &bpf_map_delete_elem_proto; 4628 case BPF_FUNC_get_prandom_u32: 4629 return &bpf_get_prandom_u32_proto; 4630 case BPF_FUNC_get_smp_processor_id: 4631 return &bpf_get_raw_smp_processor_id_proto; 4632 case BPF_FUNC_get_numa_node_id: 4633 return &bpf_get_numa_node_id_proto; 4634 case BPF_FUNC_tail_call: 4635 return &bpf_tail_call_proto; 4636 case BPF_FUNC_ktime_get_ns: 4637 return &bpf_ktime_get_ns_proto; 4638 case BPF_FUNC_trace_printk: 4639 if (capable(CAP_SYS_ADMIN)) 4640 return bpf_get_trace_printk_proto(); 4641 default: 4642 return NULL; 4643 } 4644 } 4645 4646 static const struct bpf_func_proto * 4647 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4648 { 4649 switch (func_id) { 4650 /* inet and inet6 sockets are created in a process 4651 * context so there is always a valid uid/gid 4652 */ 4653 case BPF_FUNC_get_current_uid_gid: 4654 return &bpf_get_current_uid_gid_proto; 4655 default: 4656 return bpf_base_func_proto(func_id); 4657 } 4658 } 4659 4660 static const struct bpf_func_proto * 4661 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4662 { 4663 switch (func_id) { 4664 /* inet and inet6 sockets are created in a process 4665 * context so there is always a valid uid/gid 4666 */ 4667 case BPF_FUNC_get_current_uid_gid: 4668 return &bpf_get_current_uid_gid_proto; 4669 case BPF_FUNC_bind: 4670 switch (prog->expected_attach_type) { 4671 case BPF_CGROUP_INET4_CONNECT: 4672 case BPF_CGROUP_INET6_CONNECT: 4673 return &bpf_bind_proto; 4674 default: 4675 return NULL; 4676 } 4677 default: 4678 return bpf_base_func_proto(func_id); 4679 } 4680 } 4681 4682 static const struct bpf_func_proto * 4683 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4684 { 4685 switch (func_id) { 4686 case BPF_FUNC_skb_load_bytes: 4687 return &bpf_skb_load_bytes_proto; 4688 case BPF_FUNC_skb_load_bytes_relative: 4689 return &bpf_skb_load_bytes_relative_proto; 4690 case BPF_FUNC_get_socket_cookie: 4691 return &bpf_get_socket_cookie_proto; 4692 case BPF_FUNC_get_socket_uid: 4693 return &bpf_get_socket_uid_proto; 4694 default: 4695 return bpf_base_func_proto(func_id); 4696 } 4697 } 4698 4699 static const struct bpf_func_proto * 4700 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4701 { 4702 switch (func_id) { 4703 case BPF_FUNC_skb_store_bytes: 4704 return &bpf_skb_store_bytes_proto; 4705 case BPF_FUNC_skb_load_bytes: 4706 return &bpf_skb_load_bytes_proto; 4707 case BPF_FUNC_skb_load_bytes_relative: 4708 return &bpf_skb_load_bytes_relative_proto; 4709 case BPF_FUNC_skb_pull_data: 4710 return &bpf_skb_pull_data_proto; 4711 case BPF_FUNC_csum_diff: 4712 return &bpf_csum_diff_proto; 4713 case BPF_FUNC_csum_update: 4714 return &bpf_csum_update_proto; 4715 case BPF_FUNC_l3_csum_replace: 4716 return &bpf_l3_csum_replace_proto; 4717 case BPF_FUNC_l4_csum_replace: 4718 return &bpf_l4_csum_replace_proto; 4719 case BPF_FUNC_clone_redirect: 4720 return &bpf_clone_redirect_proto; 4721 case BPF_FUNC_get_cgroup_classid: 4722 return &bpf_get_cgroup_classid_proto; 4723 case BPF_FUNC_skb_vlan_push: 4724 return &bpf_skb_vlan_push_proto; 4725 case BPF_FUNC_skb_vlan_pop: 4726 return &bpf_skb_vlan_pop_proto; 4727 case BPF_FUNC_skb_change_proto: 4728 return &bpf_skb_change_proto_proto; 4729 case BPF_FUNC_skb_change_type: 4730 return &bpf_skb_change_type_proto; 4731 case BPF_FUNC_skb_adjust_room: 4732 return &bpf_skb_adjust_room_proto; 4733 case BPF_FUNC_skb_change_tail: 4734 return &bpf_skb_change_tail_proto; 4735 case BPF_FUNC_skb_get_tunnel_key: 4736 return &bpf_skb_get_tunnel_key_proto; 4737 case BPF_FUNC_skb_set_tunnel_key: 4738 return bpf_get_skb_set_tunnel_proto(func_id); 4739 case BPF_FUNC_skb_get_tunnel_opt: 4740 return &bpf_skb_get_tunnel_opt_proto; 4741 case BPF_FUNC_skb_set_tunnel_opt: 4742 return bpf_get_skb_set_tunnel_proto(func_id); 4743 case BPF_FUNC_redirect: 4744 return &bpf_redirect_proto; 4745 case BPF_FUNC_get_route_realm: 4746 return &bpf_get_route_realm_proto; 4747 case BPF_FUNC_get_hash_recalc: 4748 return &bpf_get_hash_recalc_proto; 4749 case BPF_FUNC_set_hash_invalid: 4750 return &bpf_set_hash_invalid_proto; 4751 case BPF_FUNC_set_hash: 4752 return &bpf_set_hash_proto; 4753 case BPF_FUNC_perf_event_output: 4754 return &bpf_skb_event_output_proto; 4755 case BPF_FUNC_get_smp_processor_id: 4756 return &bpf_get_smp_processor_id_proto; 4757 case BPF_FUNC_skb_under_cgroup: 4758 return &bpf_skb_under_cgroup_proto; 4759 case BPF_FUNC_get_socket_cookie: 4760 return &bpf_get_socket_cookie_proto; 4761 case BPF_FUNC_get_socket_uid: 4762 return &bpf_get_socket_uid_proto; 4763 case BPF_FUNC_fib_lookup: 4764 return &bpf_skb_fib_lookup_proto; 4765 #ifdef CONFIG_XFRM 4766 case BPF_FUNC_skb_get_xfrm_state: 4767 return &bpf_skb_get_xfrm_state_proto; 4768 #endif 4769 #ifdef CONFIG_SOCK_CGROUP_DATA 4770 case BPF_FUNC_skb_cgroup_id: 4771 return &bpf_skb_cgroup_id_proto; 4772 #endif 4773 default: 4774 return bpf_base_func_proto(func_id); 4775 } 4776 } 4777 4778 static const struct bpf_func_proto * 4779 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4780 { 4781 switch (func_id) { 4782 case BPF_FUNC_perf_event_output: 4783 return &bpf_xdp_event_output_proto; 4784 case BPF_FUNC_get_smp_processor_id: 4785 return &bpf_get_smp_processor_id_proto; 4786 case BPF_FUNC_csum_diff: 4787 return &bpf_csum_diff_proto; 4788 case BPF_FUNC_xdp_adjust_head: 4789 return &bpf_xdp_adjust_head_proto; 4790 case BPF_FUNC_xdp_adjust_meta: 4791 return &bpf_xdp_adjust_meta_proto; 4792 case BPF_FUNC_redirect: 4793 return &bpf_xdp_redirect_proto; 4794 case BPF_FUNC_redirect_map: 4795 return &bpf_xdp_redirect_map_proto; 4796 case BPF_FUNC_xdp_adjust_tail: 4797 return &bpf_xdp_adjust_tail_proto; 4798 case BPF_FUNC_fib_lookup: 4799 return &bpf_xdp_fib_lookup_proto; 4800 default: 4801 return bpf_base_func_proto(func_id); 4802 } 4803 } 4804 4805 static const struct bpf_func_proto * 4806 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4807 { 4808 switch (func_id) { 4809 case BPF_FUNC_setsockopt: 4810 return &bpf_setsockopt_proto; 4811 case BPF_FUNC_getsockopt: 4812 return &bpf_getsockopt_proto; 4813 case BPF_FUNC_sock_ops_cb_flags_set: 4814 return &bpf_sock_ops_cb_flags_set_proto; 4815 case BPF_FUNC_sock_map_update: 4816 return &bpf_sock_map_update_proto; 4817 case BPF_FUNC_sock_hash_update: 4818 return &bpf_sock_hash_update_proto; 4819 default: 4820 return bpf_base_func_proto(func_id); 4821 } 4822 } 4823 4824 static const struct bpf_func_proto * 4825 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4826 { 4827 switch (func_id) { 4828 case BPF_FUNC_msg_redirect_map: 4829 return &bpf_msg_redirect_map_proto; 4830 case BPF_FUNC_msg_redirect_hash: 4831 return &bpf_msg_redirect_hash_proto; 4832 case BPF_FUNC_msg_apply_bytes: 4833 return &bpf_msg_apply_bytes_proto; 4834 case BPF_FUNC_msg_cork_bytes: 4835 return &bpf_msg_cork_bytes_proto; 4836 case BPF_FUNC_msg_pull_data: 4837 return &bpf_msg_pull_data_proto; 4838 default: 4839 return bpf_base_func_proto(func_id); 4840 } 4841 } 4842 4843 static const struct bpf_func_proto * 4844 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4845 { 4846 switch (func_id) { 4847 case BPF_FUNC_skb_store_bytes: 4848 return &bpf_skb_store_bytes_proto; 4849 case BPF_FUNC_skb_load_bytes: 4850 return &bpf_skb_load_bytes_proto; 4851 case BPF_FUNC_skb_pull_data: 4852 return &bpf_skb_pull_data_proto; 4853 case BPF_FUNC_skb_change_tail: 4854 return &bpf_skb_change_tail_proto; 4855 case BPF_FUNC_skb_change_head: 4856 return &bpf_skb_change_head_proto; 4857 case BPF_FUNC_get_socket_cookie: 4858 return &bpf_get_socket_cookie_proto; 4859 case BPF_FUNC_get_socket_uid: 4860 return &bpf_get_socket_uid_proto; 4861 case BPF_FUNC_sk_redirect_map: 4862 return &bpf_sk_redirect_map_proto; 4863 case BPF_FUNC_sk_redirect_hash: 4864 return &bpf_sk_redirect_hash_proto; 4865 default: 4866 return bpf_base_func_proto(func_id); 4867 } 4868 } 4869 4870 static const struct bpf_func_proto * 4871 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4872 { 4873 switch (func_id) { 4874 case BPF_FUNC_skb_load_bytes: 4875 return &bpf_skb_load_bytes_proto; 4876 case BPF_FUNC_skb_pull_data: 4877 return &bpf_skb_pull_data_proto; 4878 case BPF_FUNC_csum_diff: 4879 return &bpf_csum_diff_proto; 4880 case BPF_FUNC_get_cgroup_classid: 4881 return &bpf_get_cgroup_classid_proto; 4882 case BPF_FUNC_get_route_realm: 4883 return &bpf_get_route_realm_proto; 4884 case BPF_FUNC_get_hash_recalc: 4885 return &bpf_get_hash_recalc_proto; 4886 case BPF_FUNC_perf_event_output: 4887 return &bpf_skb_event_output_proto; 4888 case BPF_FUNC_get_smp_processor_id: 4889 return &bpf_get_smp_processor_id_proto; 4890 case BPF_FUNC_skb_under_cgroup: 4891 return &bpf_skb_under_cgroup_proto; 4892 default: 4893 return bpf_base_func_proto(func_id); 4894 } 4895 } 4896 4897 static const struct bpf_func_proto * 4898 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4899 { 4900 switch (func_id) { 4901 case BPF_FUNC_lwt_push_encap: 4902 return &bpf_lwt_push_encap_proto; 4903 default: 4904 return lwt_out_func_proto(func_id, prog); 4905 } 4906 } 4907 4908 static const struct bpf_func_proto * 4909 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4910 { 4911 switch (func_id) { 4912 case BPF_FUNC_skb_get_tunnel_key: 4913 return &bpf_skb_get_tunnel_key_proto; 4914 case BPF_FUNC_skb_set_tunnel_key: 4915 return bpf_get_skb_set_tunnel_proto(func_id); 4916 case BPF_FUNC_skb_get_tunnel_opt: 4917 return &bpf_skb_get_tunnel_opt_proto; 4918 case BPF_FUNC_skb_set_tunnel_opt: 4919 return bpf_get_skb_set_tunnel_proto(func_id); 4920 case BPF_FUNC_redirect: 4921 return &bpf_redirect_proto; 4922 case BPF_FUNC_clone_redirect: 4923 return &bpf_clone_redirect_proto; 4924 case BPF_FUNC_skb_change_tail: 4925 return &bpf_skb_change_tail_proto; 4926 case BPF_FUNC_skb_change_head: 4927 return &bpf_skb_change_head_proto; 4928 case BPF_FUNC_skb_store_bytes: 4929 return &bpf_skb_store_bytes_proto; 4930 case BPF_FUNC_csum_update: 4931 return &bpf_csum_update_proto; 4932 case BPF_FUNC_l3_csum_replace: 4933 return &bpf_l3_csum_replace_proto; 4934 case BPF_FUNC_l4_csum_replace: 4935 return &bpf_l4_csum_replace_proto; 4936 case BPF_FUNC_set_hash_invalid: 4937 return &bpf_set_hash_invalid_proto; 4938 default: 4939 return lwt_out_func_proto(func_id, prog); 4940 } 4941 } 4942 4943 static const struct bpf_func_proto * 4944 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 4945 { 4946 switch (func_id) { 4947 case BPF_FUNC_lwt_seg6_store_bytes: 4948 return &bpf_lwt_seg6_store_bytes_proto; 4949 case BPF_FUNC_lwt_seg6_action: 4950 return &bpf_lwt_seg6_action_proto; 4951 case BPF_FUNC_lwt_seg6_adjust_srh: 4952 return &bpf_lwt_seg6_adjust_srh_proto; 4953 default: 4954 return lwt_out_func_proto(func_id, prog); 4955 } 4956 } 4957 4958 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type, 4959 const struct bpf_prog *prog, 4960 struct bpf_insn_access_aux *info) 4961 { 4962 const int size_default = sizeof(__u32); 4963 4964 if (off < 0 || off >= sizeof(struct __sk_buff)) 4965 return false; 4966 4967 /* The verifier guarantees that size > 0. */ 4968 if (off % size != 0) 4969 return false; 4970 4971 switch (off) { 4972 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 4973 if (off + size > offsetofend(struct __sk_buff, cb[4])) 4974 return false; 4975 break; 4976 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]): 4977 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]): 4978 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4): 4979 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4): 4980 case bpf_ctx_range(struct __sk_buff, data): 4981 case bpf_ctx_range(struct __sk_buff, data_meta): 4982 case bpf_ctx_range(struct __sk_buff, data_end): 4983 if (size != size_default) 4984 return false; 4985 break; 4986 default: 4987 /* Only narrow read access allowed for now. */ 4988 if (type == BPF_WRITE) { 4989 if (size != size_default) 4990 return false; 4991 } else { 4992 bpf_ctx_record_field_size(info, size_default); 4993 if (!bpf_ctx_narrow_access_ok(off, size, size_default)) 4994 return false; 4995 } 4996 } 4997 4998 return true; 4999 } 5000 5001 static bool sk_filter_is_valid_access(int off, int size, 5002 enum bpf_access_type type, 5003 const struct bpf_prog *prog, 5004 struct bpf_insn_access_aux *info) 5005 { 5006 switch (off) { 5007 case bpf_ctx_range(struct __sk_buff, tc_classid): 5008 case bpf_ctx_range(struct __sk_buff, data): 5009 case bpf_ctx_range(struct __sk_buff, data_meta): 5010 case bpf_ctx_range(struct __sk_buff, data_end): 5011 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5012 return false; 5013 } 5014 5015 if (type == BPF_WRITE) { 5016 switch (off) { 5017 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5018 break; 5019 default: 5020 return false; 5021 } 5022 } 5023 5024 return bpf_skb_is_valid_access(off, size, type, prog, info); 5025 } 5026 5027 static bool lwt_is_valid_access(int off, int size, 5028 enum bpf_access_type type, 5029 const struct bpf_prog *prog, 5030 struct bpf_insn_access_aux *info) 5031 { 5032 switch (off) { 5033 case bpf_ctx_range(struct __sk_buff, tc_classid): 5034 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5035 case bpf_ctx_range(struct __sk_buff, data_meta): 5036 return false; 5037 } 5038 5039 if (type == BPF_WRITE) { 5040 switch (off) { 5041 case bpf_ctx_range(struct __sk_buff, mark): 5042 case bpf_ctx_range(struct __sk_buff, priority): 5043 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5044 break; 5045 default: 5046 return false; 5047 } 5048 } 5049 5050 switch (off) { 5051 case bpf_ctx_range(struct __sk_buff, data): 5052 info->reg_type = PTR_TO_PACKET; 5053 break; 5054 case bpf_ctx_range(struct __sk_buff, data_end): 5055 info->reg_type = PTR_TO_PACKET_END; 5056 break; 5057 } 5058 5059 return bpf_skb_is_valid_access(off, size, type, prog, info); 5060 } 5061 5062 /* Attach type specific accesses */ 5063 static bool __sock_filter_check_attach_type(int off, 5064 enum bpf_access_type access_type, 5065 enum bpf_attach_type attach_type) 5066 { 5067 switch (off) { 5068 case offsetof(struct bpf_sock, bound_dev_if): 5069 case offsetof(struct bpf_sock, mark): 5070 case offsetof(struct bpf_sock, priority): 5071 switch (attach_type) { 5072 case BPF_CGROUP_INET_SOCK_CREATE: 5073 goto full_access; 5074 default: 5075 return false; 5076 } 5077 case bpf_ctx_range(struct bpf_sock, src_ip4): 5078 switch (attach_type) { 5079 case BPF_CGROUP_INET4_POST_BIND: 5080 goto read_only; 5081 default: 5082 return false; 5083 } 5084 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5085 switch (attach_type) { 5086 case BPF_CGROUP_INET6_POST_BIND: 5087 goto read_only; 5088 default: 5089 return false; 5090 } 5091 case bpf_ctx_range(struct bpf_sock, src_port): 5092 switch (attach_type) { 5093 case BPF_CGROUP_INET4_POST_BIND: 5094 case BPF_CGROUP_INET6_POST_BIND: 5095 goto read_only; 5096 default: 5097 return false; 5098 } 5099 } 5100 read_only: 5101 return access_type == BPF_READ; 5102 full_access: 5103 return true; 5104 } 5105 5106 static bool __sock_filter_check_size(int off, int size, 5107 struct bpf_insn_access_aux *info) 5108 { 5109 const int size_default = sizeof(__u32); 5110 5111 switch (off) { 5112 case bpf_ctx_range(struct bpf_sock, src_ip4): 5113 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5114 bpf_ctx_record_field_size(info, size_default); 5115 return bpf_ctx_narrow_access_ok(off, size, size_default); 5116 } 5117 5118 return size == size_default; 5119 } 5120 5121 static bool sock_filter_is_valid_access(int off, int size, 5122 enum bpf_access_type type, 5123 const struct bpf_prog *prog, 5124 struct bpf_insn_access_aux *info) 5125 { 5126 if (off < 0 || off >= sizeof(struct bpf_sock)) 5127 return false; 5128 if (off % size != 0) 5129 return false; 5130 if (!__sock_filter_check_attach_type(off, type, 5131 prog->expected_attach_type)) 5132 return false; 5133 if (!__sock_filter_check_size(off, size, info)) 5134 return false; 5135 return true; 5136 } 5137 5138 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write, 5139 const struct bpf_prog *prog, int drop_verdict) 5140 { 5141 struct bpf_insn *insn = insn_buf; 5142 5143 if (!direct_write) 5144 return 0; 5145 5146 /* if (!skb->cloned) 5147 * goto start; 5148 * 5149 * (Fast-path, otherwise approximation that we might be 5150 * a clone, do the rest in helper.) 5151 */ 5152 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET()); 5153 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK); 5154 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7); 5155 5156 /* ret = bpf_skb_pull_data(skb, 0); */ 5157 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1); 5158 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2); 5159 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, 5160 BPF_FUNC_skb_pull_data); 5161 /* if (!ret) 5162 * goto restore; 5163 * return TC_ACT_SHOT; 5164 */ 5165 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2); 5166 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict); 5167 *insn++ = BPF_EXIT_INSN(); 5168 5169 /* restore: */ 5170 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6); 5171 /* start: */ 5172 *insn++ = prog->insnsi[0]; 5173 5174 return insn - insn_buf; 5175 } 5176 5177 static int bpf_gen_ld_abs(const struct bpf_insn *orig, 5178 struct bpf_insn *insn_buf) 5179 { 5180 bool indirect = BPF_MODE(orig->code) == BPF_IND; 5181 struct bpf_insn *insn = insn_buf; 5182 5183 /* We're guaranteed here that CTX is in R6. */ 5184 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX); 5185 if (!indirect) { 5186 *insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm); 5187 } else { 5188 *insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg); 5189 if (orig->imm) 5190 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm); 5191 } 5192 5193 switch (BPF_SIZE(orig->code)) { 5194 case BPF_B: 5195 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache); 5196 break; 5197 case BPF_H: 5198 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache); 5199 break; 5200 case BPF_W: 5201 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache); 5202 break; 5203 } 5204 5205 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2); 5206 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0); 5207 *insn++ = BPF_EXIT_INSN(); 5208 5209 return insn - insn_buf; 5210 } 5211 5212 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, 5213 const struct bpf_prog *prog) 5214 { 5215 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT); 5216 } 5217 5218 static bool tc_cls_act_is_valid_access(int off, int size, 5219 enum bpf_access_type type, 5220 const struct bpf_prog *prog, 5221 struct bpf_insn_access_aux *info) 5222 { 5223 if (type == BPF_WRITE) { 5224 switch (off) { 5225 case bpf_ctx_range(struct __sk_buff, mark): 5226 case bpf_ctx_range(struct __sk_buff, tc_index): 5227 case bpf_ctx_range(struct __sk_buff, priority): 5228 case bpf_ctx_range(struct __sk_buff, tc_classid): 5229 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]): 5230 break; 5231 default: 5232 return false; 5233 } 5234 } 5235 5236 switch (off) { 5237 case bpf_ctx_range(struct __sk_buff, data): 5238 info->reg_type = PTR_TO_PACKET; 5239 break; 5240 case bpf_ctx_range(struct __sk_buff, data_meta): 5241 info->reg_type = PTR_TO_PACKET_META; 5242 break; 5243 case bpf_ctx_range(struct __sk_buff, data_end): 5244 info->reg_type = PTR_TO_PACKET_END; 5245 break; 5246 case bpf_ctx_range_till(struct __sk_buff, family, local_port): 5247 return false; 5248 } 5249 5250 return bpf_skb_is_valid_access(off, size, type, prog, info); 5251 } 5252 5253 static bool __is_valid_xdp_access(int off, int size) 5254 { 5255 if (off < 0 || off >= sizeof(struct xdp_md)) 5256 return false; 5257 if (off % size != 0) 5258 return false; 5259 if (size != sizeof(__u32)) 5260 return false; 5261 5262 return true; 5263 } 5264 5265 static bool xdp_is_valid_access(int off, int size, 5266 enum bpf_access_type type, 5267 const struct bpf_prog *prog, 5268 struct bpf_insn_access_aux *info) 5269 { 5270 if (type == BPF_WRITE) { 5271 if (bpf_prog_is_dev_bound(prog->aux)) { 5272 switch (off) { 5273 case offsetof(struct xdp_md, rx_queue_index): 5274 return __is_valid_xdp_access(off, size); 5275 } 5276 } 5277 return false; 5278 } 5279 5280 switch (off) { 5281 case offsetof(struct xdp_md, data): 5282 info->reg_type = PTR_TO_PACKET; 5283 break; 5284 case offsetof(struct xdp_md, data_meta): 5285 info->reg_type = PTR_TO_PACKET_META; 5286 break; 5287 case offsetof(struct xdp_md, data_end): 5288 info->reg_type = PTR_TO_PACKET_END; 5289 break; 5290 } 5291 5292 return __is_valid_xdp_access(off, size); 5293 } 5294 5295 void bpf_warn_invalid_xdp_action(u32 act) 5296 { 5297 const u32 act_max = XDP_REDIRECT; 5298 5299 WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n", 5300 act > act_max ? "Illegal" : "Driver unsupported", 5301 act); 5302 } 5303 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action); 5304 5305 static bool sock_addr_is_valid_access(int off, int size, 5306 enum bpf_access_type type, 5307 const struct bpf_prog *prog, 5308 struct bpf_insn_access_aux *info) 5309 { 5310 const int size_default = sizeof(__u32); 5311 5312 if (off < 0 || off >= sizeof(struct bpf_sock_addr)) 5313 return false; 5314 if (off % size != 0) 5315 return false; 5316 5317 /* Disallow access to IPv6 fields from IPv4 contex and vise 5318 * versa. 5319 */ 5320 switch (off) { 5321 case bpf_ctx_range(struct bpf_sock_addr, user_ip4): 5322 switch (prog->expected_attach_type) { 5323 case BPF_CGROUP_INET4_BIND: 5324 case BPF_CGROUP_INET4_CONNECT: 5325 case BPF_CGROUP_UDP4_SENDMSG: 5326 break; 5327 default: 5328 return false; 5329 } 5330 break; 5331 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 5332 switch (prog->expected_attach_type) { 5333 case BPF_CGROUP_INET6_BIND: 5334 case BPF_CGROUP_INET6_CONNECT: 5335 case BPF_CGROUP_UDP6_SENDMSG: 5336 break; 5337 default: 5338 return false; 5339 } 5340 break; 5341 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4): 5342 switch (prog->expected_attach_type) { 5343 case BPF_CGROUP_UDP4_SENDMSG: 5344 break; 5345 default: 5346 return false; 5347 } 5348 break; 5349 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 5350 msg_src_ip6[3]): 5351 switch (prog->expected_attach_type) { 5352 case BPF_CGROUP_UDP6_SENDMSG: 5353 break; 5354 default: 5355 return false; 5356 } 5357 break; 5358 } 5359 5360 switch (off) { 5361 case bpf_ctx_range(struct bpf_sock_addr, user_ip4): 5362 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 5363 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4): 5364 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 5365 msg_src_ip6[3]): 5366 /* Only narrow read access allowed for now. */ 5367 if (type == BPF_READ) { 5368 bpf_ctx_record_field_size(info, size_default); 5369 if (!bpf_ctx_narrow_access_ok(off, size, size_default)) 5370 return false; 5371 } else { 5372 if (size != size_default) 5373 return false; 5374 } 5375 break; 5376 case bpf_ctx_range(struct bpf_sock_addr, user_port): 5377 if (size != size_default) 5378 return false; 5379 break; 5380 default: 5381 if (type == BPF_READ) { 5382 if (size != size_default) 5383 return false; 5384 } else { 5385 return false; 5386 } 5387 } 5388 5389 return true; 5390 } 5391 5392 static bool sock_ops_is_valid_access(int off, int size, 5393 enum bpf_access_type type, 5394 const struct bpf_prog *prog, 5395 struct bpf_insn_access_aux *info) 5396 { 5397 const int size_default = sizeof(__u32); 5398 5399 if (off < 0 || off >= sizeof(struct bpf_sock_ops)) 5400 return false; 5401 5402 /* The verifier guarantees that size > 0. */ 5403 if (off % size != 0) 5404 return false; 5405 5406 if (type == BPF_WRITE) { 5407 switch (off) { 5408 case offsetof(struct bpf_sock_ops, reply): 5409 case offsetof(struct bpf_sock_ops, sk_txhash): 5410 if (size != size_default) 5411 return false; 5412 break; 5413 default: 5414 return false; 5415 } 5416 } else { 5417 switch (off) { 5418 case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received, 5419 bytes_acked): 5420 if (size != sizeof(__u64)) 5421 return false; 5422 break; 5423 default: 5424 if (size != size_default) 5425 return false; 5426 break; 5427 } 5428 } 5429 5430 return true; 5431 } 5432 5433 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write, 5434 const struct bpf_prog *prog) 5435 { 5436 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP); 5437 } 5438 5439 static bool sk_skb_is_valid_access(int off, int size, 5440 enum bpf_access_type type, 5441 const struct bpf_prog *prog, 5442 struct bpf_insn_access_aux *info) 5443 { 5444 switch (off) { 5445 case bpf_ctx_range(struct __sk_buff, tc_classid): 5446 case bpf_ctx_range(struct __sk_buff, data_meta): 5447 return false; 5448 } 5449 5450 if (type == BPF_WRITE) { 5451 switch (off) { 5452 case bpf_ctx_range(struct __sk_buff, tc_index): 5453 case bpf_ctx_range(struct __sk_buff, priority): 5454 break; 5455 default: 5456 return false; 5457 } 5458 } 5459 5460 switch (off) { 5461 case bpf_ctx_range(struct __sk_buff, mark): 5462 return false; 5463 case bpf_ctx_range(struct __sk_buff, data): 5464 info->reg_type = PTR_TO_PACKET; 5465 break; 5466 case bpf_ctx_range(struct __sk_buff, data_end): 5467 info->reg_type = PTR_TO_PACKET_END; 5468 break; 5469 } 5470 5471 return bpf_skb_is_valid_access(off, size, type, prog, info); 5472 } 5473 5474 static bool sk_msg_is_valid_access(int off, int size, 5475 enum bpf_access_type type, 5476 const struct bpf_prog *prog, 5477 struct bpf_insn_access_aux *info) 5478 { 5479 if (type == BPF_WRITE) 5480 return false; 5481 5482 switch (off) { 5483 case offsetof(struct sk_msg_md, data): 5484 info->reg_type = PTR_TO_PACKET; 5485 if (size != sizeof(__u64)) 5486 return false; 5487 break; 5488 case offsetof(struct sk_msg_md, data_end): 5489 info->reg_type = PTR_TO_PACKET_END; 5490 if (size != sizeof(__u64)) 5491 return false; 5492 break; 5493 default: 5494 if (size != sizeof(__u32)) 5495 return false; 5496 } 5497 5498 if (off < 0 || off >= sizeof(struct sk_msg_md)) 5499 return false; 5500 if (off % size != 0) 5501 return false; 5502 5503 return true; 5504 } 5505 5506 static u32 bpf_convert_ctx_access(enum bpf_access_type type, 5507 const struct bpf_insn *si, 5508 struct bpf_insn *insn_buf, 5509 struct bpf_prog *prog, u32 *target_size) 5510 { 5511 struct bpf_insn *insn = insn_buf; 5512 int off; 5513 5514 switch (si->off) { 5515 case offsetof(struct __sk_buff, len): 5516 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5517 bpf_target_off(struct sk_buff, len, 4, 5518 target_size)); 5519 break; 5520 5521 case offsetof(struct __sk_buff, protocol): 5522 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5523 bpf_target_off(struct sk_buff, protocol, 2, 5524 target_size)); 5525 break; 5526 5527 case offsetof(struct __sk_buff, vlan_proto): 5528 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5529 bpf_target_off(struct sk_buff, vlan_proto, 2, 5530 target_size)); 5531 break; 5532 5533 case offsetof(struct __sk_buff, priority): 5534 if (type == BPF_WRITE) 5535 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5536 bpf_target_off(struct sk_buff, priority, 4, 5537 target_size)); 5538 else 5539 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5540 bpf_target_off(struct sk_buff, priority, 4, 5541 target_size)); 5542 break; 5543 5544 case offsetof(struct __sk_buff, ingress_ifindex): 5545 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5546 bpf_target_off(struct sk_buff, skb_iif, 4, 5547 target_size)); 5548 break; 5549 5550 case offsetof(struct __sk_buff, ifindex): 5551 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 5552 si->dst_reg, si->src_reg, 5553 offsetof(struct sk_buff, dev)); 5554 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1); 5555 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5556 bpf_target_off(struct net_device, ifindex, 4, 5557 target_size)); 5558 break; 5559 5560 case offsetof(struct __sk_buff, hash): 5561 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5562 bpf_target_off(struct sk_buff, hash, 4, 5563 target_size)); 5564 break; 5565 5566 case offsetof(struct __sk_buff, mark): 5567 if (type == BPF_WRITE) 5568 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5569 bpf_target_off(struct sk_buff, mark, 4, 5570 target_size)); 5571 else 5572 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5573 bpf_target_off(struct sk_buff, mark, 4, 5574 target_size)); 5575 break; 5576 5577 case offsetof(struct __sk_buff, pkt_type): 5578 *target_size = 1; 5579 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg, 5580 PKT_TYPE_OFFSET()); 5581 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX); 5582 #ifdef __BIG_ENDIAN_BITFIELD 5583 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5); 5584 #endif 5585 break; 5586 5587 case offsetof(struct __sk_buff, queue_mapping): 5588 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5589 bpf_target_off(struct sk_buff, queue_mapping, 2, 5590 target_size)); 5591 break; 5592 5593 case offsetof(struct __sk_buff, vlan_present): 5594 case offsetof(struct __sk_buff, vlan_tci): 5595 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); 5596 5597 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5598 bpf_target_off(struct sk_buff, vlan_tci, 2, 5599 target_size)); 5600 if (si->off == offsetof(struct __sk_buff, vlan_tci)) { 5601 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 5602 ~VLAN_TAG_PRESENT); 5603 } else { 5604 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12); 5605 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1); 5606 } 5607 break; 5608 5609 case offsetof(struct __sk_buff, cb[0]) ... 5610 offsetofend(struct __sk_buff, cb[4]) - 1: 5611 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20); 5612 BUILD_BUG_ON((offsetof(struct sk_buff, cb) + 5613 offsetof(struct qdisc_skb_cb, data)) % 5614 sizeof(__u64)); 5615 5616 prog->cb_access = 1; 5617 off = si->off; 5618 off -= offsetof(struct __sk_buff, cb[0]); 5619 off += offsetof(struct sk_buff, cb); 5620 off += offsetof(struct qdisc_skb_cb, data); 5621 if (type == BPF_WRITE) 5622 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg, 5623 si->src_reg, off); 5624 else 5625 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg, 5626 si->src_reg, off); 5627 break; 5628 5629 case offsetof(struct __sk_buff, tc_classid): 5630 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2); 5631 5632 off = si->off; 5633 off -= offsetof(struct __sk_buff, tc_classid); 5634 off += offsetof(struct sk_buff, cb); 5635 off += offsetof(struct qdisc_skb_cb, tc_classid); 5636 *target_size = 2; 5637 if (type == BPF_WRITE) 5638 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, 5639 si->src_reg, off); 5640 else 5641 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, 5642 si->src_reg, off); 5643 break; 5644 5645 case offsetof(struct __sk_buff, data): 5646 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data), 5647 si->dst_reg, si->src_reg, 5648 offsetof(struct sk_buff, data)); 5649 break; 5650 5651 case offsetof(struct __sk_buff, data_meta): 5652 off = si->off; 5653 off -= offsetof(struct __sk_buff, data_meta); 5654 off += offsetof(struct sk_buff, cb); 5655 off += offsetof(struct bpf_skb_data_end, data_meta); 5656 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 5657 si->src_reg, off); 5658 break; 5659 5660 case offsetof(struct __sk_buff, data_end): 5661 off = si->off; 5662 off -= offsetof(struct __sk_buff, data_end); 5663 off += offsetof(struct sk_buff, cb); 5664 off += offsetof(struct bpf_skb_data_end, data_end); 5665 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 5666 si->src_reg, off); 5667 break; 5668 5669 case offsetof(struct __sk_buff, tc_index): 5670 #ifdef CONFIG_NET_SCHED 5671 if (type == BPF_WRITE) 5672 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg, 5673 bpf_target_off(struct sk_buff, tc_index, 2, 5674 target_size)); 5675 else 5676 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5677 bpf_target_off(struct sk_buff, tc_index, 2, 5678 target_size)); 5679 #else 5680 *target_size = 2; 5681 if (type == BPF_WRITE) 5682 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg); 5683 else 5684 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 5685 #endif 5686 break; 5687 5688 case offsetof(struct __sk_buff, napi_id): 5689 #if defined(CONFIG_NET_RX_BUSY_POLL) 5690 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5691 bpf_target_off(struct sk_buff, napi_id, 4, 5692 target_size)); 5693 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1); 5694 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 5695 #else 5696 *target_size = 4; 5697 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0); 5698 #endif 5699 break; 5700 case offsetof(struct __sk_buff, family): 5701 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 5702 5703 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5704 si->dst_reg, si->src_reg, 5705 offsetof(struct sk_buff, sk)); 5706 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 5707 bpf_target_off(struct sock_common, 5708 skc_family, 5709 2, target_size)); 5710 break; 5711 case offsetof(struct __sk_buff, remote_ip4): 5712 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 5713 5714 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5715 si->dst_reg, si->src_reg, 5716 offsetof(struct sk_buff, sk)); 5717 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5718 bpf_target_off(struct sock_common, 5719 skc_daddr, 5720 4, target_size)); 5721 break; 5722 case offsetof(struct __sk_buff, local_ip4): 5723 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 5724 skc_rcv_saddr) != 4); 5725 5726 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5727 si->dst_reg, si->src_reg, 5728 offsetof(struct sk_buff, sk)); 5729 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5730 bpf_target_off(struct sock_common, 5731 skc_rcv_saddr, 5732 4, target_size)); 5733 break; 5734 case offsetof(struct __sk_buff, remote_ip6[0]) ... 5735 offsetof(struct __sk_buff, remote_ip6[3]): 5736 #if IS_ENABLED(CONFIG_IPV6) 5737 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 5738 skc_v6_daddr.s6_addr32[0]) != 4); 5739 5740 off = si->off; 5741 off -= offsetof(struct __sk_buff, remote_ip6[0]); 5742 5743 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5744 si->dst_reg, si->src_reg, 5745 offsetof(struct sk_buff, sk)); 5746 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5747 offsetof(struct sock_common, 5748 skc_v6_daddr.s6_addr32[0]) + 5749 off); 5750 #else 5751 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 5752 #endif 5753 break; 5754 case offsetof(struct __sk_buff, local_ip6[0]) ... 5755 offsetof(struct __sk_buff, local_ip6[3]): 5756 #if IS_ENABLED(CONFIG_IPV6) 5757 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 5758 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 5759 5760 off = si->off; 5761 off -= offsetof(struct __sk_buff, local_ip6[0]); 5762 5763 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5764 si->dst_reg, si->src_reg, 5765 offsetof(struct sk_buff, sk)); 5766 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5767 offsetof(struct sock_common, 5768 skc_v6_rcv_saddr.s6_addr32[0]) + 5769 off); 5770 #else 5771 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 5772 #endif 5773 break; 5774 5775 case offsetof(struct __sk_buff, remote_port): 5776 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 5777 5778 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5779 si->dst_reg, si->src_reg, 5780 offsetof(struct sk_buff, sk)); 5781 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 5782 bpf_target_off(struct sock_common, 5783 skc_dport, 5784 2, target_size)); 5785 #ifndef __BIG_ENDIAN_BITFIELD 5786 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 5787 #endif 5788 break; 5789 5790 case offsetof(struct __sk_buff, local_port): 5791 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 5792 5793 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk), 5794 si->dst_reg, si->src_reg, 5795 offsetof(struct sk_buff, sk)); 5796 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 5797 bpf_target_off(struct sock_common, 5798 skc_num, 2, target_size)); 5799 break; 5800 } 5801 5802 return insn - insn_buf; 5803 } 5804 5805 static u32 sock_filter_convert_ctx_access(enum bpf_access_type type, 5806 const struct bpf_insn *si, 5807 struct bpf_insn *insn_buf, 5808 struct bpf_prog *prog, u32 *target_size) 5809 { 5810 struct bpf_insn *insn = insn_buf; 5811 int off; 5812 5813 switch (si->off) { 5814 case offsetof(struct bpf_sock, bound_dev_if): 5815 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4); 5816 5817 if (type == BPF_WRITE) 5818 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5819 offsetof(struct sock, sk_bound_dev_if)); 5820 else 5821 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5822 offsetof(struct sock, sk_bound_dev_if)); 5823 break; 5824 5825 case offsetof(struct bpf_sock, mark): 5826 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4); 5827 5828 if (type == BPF_WRITE) 5829 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5830 offsetof(struct sock, sk_mark)); 5831 else 5832 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5833 offsetof(struct sock, sk_mark)); 5834 break; 5835 5836 case offsetof(struct bpf_sock, priority): 5837 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4); 5838 5839 if (type == BPF_WRITE) 5840 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 5841 offsetof(struct sock, sk_priority)); 5842 else 5843 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5844 offsetof(struct sock, sk_priority)); 5845 break; 5846 5847 case offsetof(struct bpf_sock, family): 5848 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2); 5849 5850 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, 5851 offsetof(struct sock, sk_family)); 5852 break; 5853 5854 case offsetof(struct bpf_sock, type): 5855 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5856 offsetof(struct sock, __sk_flags_offset)); 5857 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK); 5858 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT); 5859 break; 5860 5861 case offsetof(struct bpf_sock, protocol): 5862 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 5863 offsetof(struct sock, __sk_flags_offset)); 5864 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK); 5865 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT); 5866 break; 5867 5868 case offsetof(struct bpf_sock, src_ip4): 5869 *insn++ = BPF_LDX_MEM( 5870 BPF_SIZE(si->code), si->dst_reg, si->src_reg, 5871 bpf_target_off(struct sock_common, skc_rcv_saddr, 5872 FIELD_SIZEOF(struct sock_common, 5873 skc_rcv_saddr), 5874 target_size)); 5875 break; 5876 5877 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]): 5878 #if IS_ENABLED(CONFIG_IPV6) 5879 off = si->off; 5880 off -= offsetof(struct bpf_sock, src_ip6[0]); 5881 *insn++ = BPF_LDX_MEM( 5882 BPF_SIZE(si->code), si->dst_reg, si->src_reg, 5883 bpf_target_off( 5884 struct sock_common, 5885 skc_v6_rcv_saddr.s6_addr32[0], 5886 FIELD_SIZEOF(struct sock_common, 5887 skc_v6_rcv_saddr.s6_addr32[0]), 5888 target_size) + off); 5889 #else 5890 (void)off; 5891 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 5892 #endif 5893 break; 5894 5895 case offsetof(struct bpf_sock, src_port): 5896 *insn++ = BPF_LDX_MEM( 5897 BPF_FIELD_SIZEOF(struct sock_common, skc_num), 5898 si->dst_reg, si->src_reg, 5899 bpf_target_off(struct sock_common, skc_num, 5900 FIELD_SIZEOF(struct sock_common, 5901 skc_num), 5902 target_size)); 5903 break; 5904 } 5905 5906 return insn - insn_buf; 5907 } 5908 5909 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type, 5910 const struct bpf_insn *si, 5911 struct bpf_insn *insn_buf, 5912 struct bpf_prog *prog, u32 *target_size) 5913 { 5914 struct bpf_insn *insn = insn_buf; 5915 5916 switch (si->off) { 5917 case offsetof(struct __sk_buff, ifindex): 5918 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), 5919 si->dst_reg, si->src_reg, 5920 offsetof(struct sk_buff, dev)); 5921 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5922 bpf_target_off(struct net_device, ifindex, 4, 5923 target_size)); 5924 break; 5925 default: 5926 return bpf_convert_ctx_access(type, si, insn_buf, prog, 5927 target_size); 5928 } 5929 5930 return insn - insn_buf; 5931 } 5932 5933 static u32 xdp_convert_ctx_access(enum bpf_access_type type, 5934 const struct bpf_insn *si, 5935 struct bpf_insn *insn_buf, 5936 struct bpf_prog *prog, u32 *target_size) 5937 { 5938 struct bpf_insn *insn = insn_buf; 5939 5940 switch (si->off) { 5941 case offsetof(struct xdp_md, data): 5942 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data), 5943 si->dst_reg, si->src_reg, 5944 offsetof(struct xdp_buff, data)); 5945 break; 5946 case offsetof(struct xdp_md, data_meta): 5947 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta), 5948 si->dst_reg, si->src_reg, 5949 offsetof(struct xdp_buff, data_meta)); 5950 break; 5951 case offsetof(struct xdp_md, data_end): 5952 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end), 5953 si->dst_reg, si->src_reg, 5954 offsetof(struct xdp_buff, data_end)); 5955 break; 5956 case offsetof(struct xdp_md, ingress_ifindex): 5957 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq), 5958 si->dst_reg, si->src_reg, 5959 offsetof(struct xdp_buff, rxq)); 5960 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev), 5961 si->dst_reg, si->dst_reg, 5962 offsetof(struct xdp_rxq_info, dev)); 5963 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5964 offsetof(struct net_device, ifindex)); 5965 break; 5966 case offsetof(struct xdp_md, rx_queue_index): 5967 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq), 5968 si->dst_reg, si->src_reg, 5969 offsetof(struct xdp_buff, rxq)); 5970 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 5971 offsetof(struct xdp_rxq_info, 5972 queue_index)); 5973 break; 5974 } 5975 5976 return insn - insn_buf; 5977 } 5978 5979 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of 5980 * context Structure, F is Field in context structure that contains a pointer 5981 * to Nested Structure of type NS that has the field NF. 5982 * 5983 * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make 5984 * sure that SIZE is not greater than actual size of S.F.NF. 5985 * 5986 * If offset OFF is provided, the load happens from that offset relative to 5987 * offset of NF. 5988 */ 5989 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF) \ 5990 do { \ 5991 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg, \ 5992 si->src_reg, offsetof(S, F)); \ 5993 *insn++ = BPF_LDX_MEM( \ 5994 SIZE, si->dst_reg, si->dst_reg, \ 5995 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \ 5996 target_size) \ 5997 + OFF); \ 5998 } while (0) 5999 6000 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF) \ 6001 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, \ 6002 BPF_FIELD_SIZEOF(NS, NF), 0) 6003 6004 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to 6005 * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation. 6006 * 6007 * It doesn't support SIZE argument though since narrow stores are not 6008 * supported for now. 6009 * 6010 * In addition it uses Temporary Field TF (member of struct S) as the 3rd 6011 * "register" since two registers available in convert_ctx_access are not 6012 * enough: we can't override neither SRC, since it contains value to store, nor 6013 * DST since it contains pointer to context that may be used by later 6014 * instructions. But we need a temporary place to save pointer to nested 6015 * structure whose field we want to store to. 6016 */ 6017 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, TF) \ 6018 do { \ 6019 int tmp_reg = BPF_REG_9; \ 6020 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \ 6021 --tmp_reg; \ 6022 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \ 6023 --tmp_reg; \ 6024 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg, \ 6025 offsetof(S, TF)); \ 6026 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg, \ 6027 si->dst_reg, offsetof(S, F)); \ 6028 *insn++ = BPF_STX_MEM( \ 6029 BPF_FIELD_SIZEOF(NS, NF), tmp_reg, si->src_reg, \ 6030 bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \ 6031 target_size) \ 6032 + OFF); \ 6033 *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg, \ 6034 offsetof(S, TF)); \ 6035 } while (0) 6036 6037 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \ 6038 TF) \ 6039 do { \ 6040 if (type == BPF_WRITE) { \ 6041 SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, \ 6042 TF); \ 6043 } else { \ 6044 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( \ 6045 S, NS, F, NF, SIZE, OFF); \ 6046 } \ 6047 } while (0) 6048 6049 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF) \ 6050 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( \ 6051 S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF) 6052 6053 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type, 6054 const struct bpf_insn *si, 6055 struct bpf_insn *insn_buf, 6056 struct bpf_prog *prog, u32 *target_size) 6057 { 6058 struct bpf_insn *insn = insn_buf; 6059 int off; 6060 6061 switch (si->off) { 6062 case offsetof(struct bpf_sock_addr, user_family): 6063 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern, 6064 struct sockaddr, uaddr, sa_family); 6065 break; 6066 6067 case offsetof(struct bpf_sock_addr, user_ip4): 6068 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6069 struct bpf_sock_addr_kern, struct sockaddr_in, uaddr, 6070 sin_addr, BPF_SIZE(si->code), 0, tmp_reg); 6071 break; 6072 6073 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]): 6074 off = si->off; 6075 off -= offsetof(struct bpf_sock_addr, user_ip6[0]); 6076 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6077 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr, 6078 sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off, 6079 tmp_reg); 6080 break; 6081 6082 case offsetof(struct bpf_sock_addr, user_port): 6083 /* To get port we need to know sa_family first and then treat 6084 * sockaddr as either sockaddr_in or sockaddr_in6. 6085 * Though we can simplify since port field has same offset and 6086 * size in both structures. 6087 * Here we check this invariant and use just one of the 6088 * structures if it's true. 6089 */ 6090 BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) != 6091 offsetof(struct sockaddr_in6, sin6_port)); 6092 BUILD_BUG_ON(FIELD_SIZEOF(struct sockaddr_in, sin_port) != 6093 FIELD_SIZEOF(struct sockaddr_in6, sin6_port)); 6094 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(struct bpf_sock_addr_kern, 6095 struct sockaddr_in6, uaddr, 6096 sin6_port, tmp_reg); 6097 break; 6098 6099 case offsetof(struct bpf_sock_addr, family): 6100 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern, 6101 struct sock, sk, sk_family); 6102 break; 6103 6104 case offsetof(struct bpf_sock_addr, type): 6105 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( 6106 struct bpf_sock_addr_kern, struct sock, sk, 6107 __sk_flags_offset, BPF_W, 0); 6108 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK); 6109 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT); 6110 break; 6111 6112 case offsetof(struct bpf_sock_addr, protocol): 6113 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( 6114 struct bpf_sock_addr_kern, struct sock, sk, 6115 __sk_flags_offset, BPF_W, 0); 6116 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK); 6117 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 6118 SK_FL_PROTO_SHIFT); 6119 break; 6120 6121 case offsetof(struct bpf_sock_addr, msg_src_ip4): 6122 /* Treat t_ctx as struct in_addr for msg_src_ip4. */ 6123 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6124 struct bpf_sock_addr_kern, struct in_addr, t_ctx, 6125 s_addr, BPF_SIZE(si->code), 0, tmp_reg); 6126 break; 6127 6128 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0], 6129 msg_src_ip6[3]): 6130 off = si->off; 6131 off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]); 6132 /* Treat t_ctx as struct in6_addr for msg_src_ip6. */ 6133 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( 6134 struct bpf_sock_addr_kern, struct in6_addr, t_ctx, 6135 s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg); 6136 break; 6137 } 6138 6139 return insn - insn_buf; 6140 } 6141 6142 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, 6143 const struct bpf_insn *si, 6144 struct bpf_insn *insn_buf, 6145 struct bpf_prog *prog, 6146 u32 *target_size) 6147 { 6148 struct bpf_insn *insn = insn_buf; 6149 int off; 6150 6151 switch (si->off) { 6152 case offsetof(struct bpf_sock_ops, op) ... 6153 offsetof(struct bpf_sock_ops, replylong[3]): 6154 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) != 6155 FIELD_SIZEOF(struct bpf_sock_ops_kern, op)); 6156 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) != 6157 FIELD_SIZEOF(struct bpf_sock_ops_kern, reply)); 6158 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) != 6159 FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong)); 6160 off = si->off; 6161 off -= offsetof(struct bpf_sock_ops, op); 6162 off += offsetof(struct bpf_sock_ops_kern, op); 6163 if (type == BPF_WRITE) 6164 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg, 6165 off); 6166 else 6167 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, 6168 off); 6169 break; 6170 6171 case offsetof(struct bpf_sock_ops, family): 6172 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 6173 6174 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6175 struct bpf_sock_ops_kern, sk), 6176 si->dst_reg, si->src_reg, 6177 offsetof(struct bpf_sock_ops_kern, sk)); 6178 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6179 offsetof(struct sock_common, skc_family)); 6180 break; 6181 6182 case offsetof(struct bpf_sock_ops, remote_ip4): 6183 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 6184 6185 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6186 struct bpf_sock_ops_kern, sk), 6187 si->dst_reg, si->src_reg, 6188 offsetof(struct bpf_sock_ops_kern, sk)); 6189 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6190 offsetof(struct sock_common, skc_daddr)); 6191 break; 6192 6193 case offsetof(struct bpf_sock_ops, local_ip4): 6194 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6195 skc_rcv_saddr) != 4); 6196 6197 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6198 struct bpf_sock_ops_kern, sk), 6199 si->dst_reg, si->src_reg, 6200 offsetof(struct bpf_sock_ops_kern, sk)); 6201 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6202 offsetof(struct sock_common, 6203 skc_rcv_saddr)); 6204 break; 6205 6206 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ... 6207 offsetof(struct bpf_sock_ops, remote_ip6[3]): 6208 #if IS_ENABLED(CONFIG_IPV6) 6209 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6210 skc_v6_daddr.s6_addr32[0]) != 4); 6211 6212 off = si->off; 6213 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]); 6214 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6215 struct bpf_sock_ops_kern, sk), 6216 si->dst_reg, si->src_reg, 6217 offsetof(struct bpf_sock_ops_kern, sk)); 6218 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6219 offsetof(struct sock_common, 6220 skc_v6_daddr.s6_addr32[0]) + 6221 off); 6222 #else 6223 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6224 #endif 6225 break; 6226 6227 case offsetof(struct bpf_sock_ops, local_ip6[0]) ... 6228 offsetof(struct bpf_sock_ops, local_ip6[3]): 6229 #if IS_ENABLED(CONFIG_IPV6) 6230 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6231 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 6232 6233 off = si->off; 6234 off -= offsetof(struct bpf_sock_ops, local_ip6[0]); 6235 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6236 struct bpf_sock_ops_kern, sk), 6237 si->dst_reg, si->src_reg, 6238 offsetof(struct bpf_sock_ops_kern, sk)); 6239 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6240 offsetof(struct sock_common, 6241 skc_v6_rcv_saddr.s6_addr32[0]) + 6242 off); 6243 #else 6244 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6245 #endif 6246 break; 6247 6248 case offsetof(struct bpf_sock_ops, remote_port): 6249 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 6250 6251 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6252 struct bpf_sock_ops_kern, sk), 6253 si->dst_reg, si->src_reg, 6254 offsetof(struct bpf_sock_ops_kern, sk)); 6255 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6256 offsetof(struct sock_common, skc_dport)); 6257 #ifndef __BIG_ENDIAN_BITFIELD 6258 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 6259 #endif 6260 break; 6261 6262 case offsetof(struct bpf_sock_ops, local_port): 6263 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 6264 6265 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6266 struct bpf_sock_ops_kern, sk), 6267 si->dst_reg, si->src_reg, 6268 offsetof(struct bpf_sock_ops_kern, sk)); 6269 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6270 offsetof(struct sock_common, skc_num)); 6271 break; 6272 6273 case offsetof(struct bpf_sock_ops, is_fullsock): 6274 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6275 struct bpf_sock_ops_kern, 6276 is_fullsock), 6277 si->dst_reg, si->src_reg, 6278 offsetof(struct bpf_sock_ops_kern, 6279 is_fullsock)); 6280 break; 6281 6282 case offsetof(struct bpf_sock_ops, state): 6283 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_state) != 1); 6284 6285 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6286 struct bpf_sock_ops_kern, sk), 6287 si->dst_reg, si->src_reg, 6288 offsetof(struct bpf_sock_ops_kern, sk)); 6289 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg, 6290 offsetof(struct sock_common, skc_state)); 6291 break; 6292 6293 case offsetof(struct bpf_sock_ops, rtt_min): 6294 BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, rtt_min) != 6295 sizeof(struct minmax)); 6296 BUILD_BUG_ON(sizeof(struct minmax) < 6297 sizeof(struct minmax_sample)); 6298 6299 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6300 struct bpf_sock_ops_kern, sk), 6301 si->dst_reg, si->src_reg, 6302 offsetof(struct bpf_sock_ops_kern, sk)); 6303 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6304 offsetof(struct tcp_sock, rtt_min) + 6305 FIELD_SIZEOF(struct minmax_sample, t)); 6306 break; 6307 6308 /* Helper macro for adding read access to tcp_sock or sock fields. */ 6309 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \ 6310 do { \ 6311 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \ 6312 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \ 6313 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6314 struct bpf_sock_ops_kern, \ 6315 is_fullsock), \ 6316 si->dst_reg, si->src_reg, \ 6317 offsetof(struct bpf_sock_ops_kern, \ 6318 is_fullsock)); \ 6319 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 2); \ 6320 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6321 struct bpf_sock_ops_kern, sk),\ 6322 si->dst_reg, si->src_reg, \ 6323 offsetof(struct bpf_sock_ops_kern, sk));\ 6324 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ, \ 6325 OBJ_FIELD), \ 6326 si->dst_reg, si->dst_reg, \ 6327 offsetof(OBJ, OBJ_FIELD)); \ 6328 } while (0) 6329 6330 /* Helper macro for adding write access to tcp_sock or sock fields. 6331 * The macro is called with two registers, dst_reg which contains a pointer 6332 * to ctx (context) and src_reg which contains the value that should be 6333 * stored. However, we need an additional register since we cannot overwrite 6334 * dst_reg because it may be used later in the program. 6335 * Instead we "borrow" one of the other register. We first save its value 6336 * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore 6337 * it at the end of the macro. 6338 */ 6339 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \ 6340 do { \ 6341 int reg = BPF_REG_9; \ 6342 BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \ 6343 FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \ 6344 if (si->dst_reg == reg || si->src_reg == reg) \ 6345 reg--; \ 6346 if (si->dst_reg == reg || si->src_reg == reg) \ 6347 reg--; \ 6348 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg, \ 6349 offsetof(struct bpf_sock_ops_kern, \ 6350 temp)); \ 6351 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6352 struct bpf_sock_ops_kern, \ 6353 is_fullsock), \ 6354 reg, si->dst_reg, \ 6355 offsetof(struct bpf_sock_ops_kern, \ 6356 is_fullsock)); \ 6357 *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2); \ 6358 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \ 6359 struct bpf_sock_ops_kern, sk),\ 6360 reg, si->dst_reg, \ 6361 offsetof(struct bpf_sock_ops_kern, sk));\ 6362 *insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD), \ 6363 reg, si->src_reg, \ 6364 offsetof(OBJ, OBJ_FIELD)); \ 6365 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg, \ 6366 offsetof(struct bpf_sock_ops_kern, \ 6367 temp)); \ 6368 } while (0) 6369 6370 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE) \ 6371 do { \ 6372 if (TYPE == BPF_WRITE) \ 6373 SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \ 6374 else \ 6375 SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \ 6376 } while (0) 6377 6378 case offsetof(struct bpf_sock_ops, snd_cwnd): 6379 SOCK_OPS_GET_FIELD(snd_cwnd, snd_cwnd, struct tcp_sock); 6380 break; 6381 6382 case offsetof(struct bpf_sock_ops, srtt_us): 6383 SOCK_OPS_GET_FIELD(srtt_us, srtt_us, struct tcp_sock); 6384 break; 6385 6386 case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags): 6387 SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags, 6388 struct tcp_sock); 6389 break; 6390 6391 case offsetof(struct bpf_sock_ops, snd_ssthresh): 6392 SOCK_OPS_GET_FIELD(snd_ssthresh, snd_ssthresh, struct tcp_sock); 6393 break; 6394 6395 case offsetof(struct bpf_sock_ops, rcv_nxt): 6396 SOCK_OPS_GET_FIELD(rcv_nxt, rcv_nxt, struct tcp_sock); 6397 break; 6398 6399 case offsetof(struct bpf_sock_ops, snd_nxt): 6400 SOCK_OPS_GET_FIELD(snd_nxt, snd_nxt, struct tcp_sock); 6401 break; 6402 6403 case offsetof(struct bpf_sock_ops, snd_una): 6404 SOCK_OPS_GET_FIELD(snd_una, snd_una, struct tcp_sock); 6405 break; 6406 6407 case offsetof(struct bpf_sock_ops, mss_cache): 6408 SOCK_OPS_GET_FIELD(mss_cache, mss_cache, struct tcp_sock); 6409 break; 6410 6411 case offsetof(struct bpf_sock_ops, ecn_flags): 6412 SOCK_OPS_GET_FIELD(ecn_flags, ecn_flags, struct tcp_sock); 6413 break; 6414 6415 case offsetof(struct bpf_sock_ops, rate_delivered): 6416 SOCK_OPS_GET_FIELD(rate_delivered, rate_delivered, 6417 struct tcp_sock); 6418 break; 6419 6420 case offsetof(struct bpf_sock_ops, rate_interval_us): 6421 SOCK_OPS_GET_FIELD(rate_interval_us, rate_interval_us, 6422 struct tcp_sock); 6423 break; 6424 6425 case offsetof(struct bpf_sock_ops, packets_out): 6426 SOCK_OPS_GET_FIELD(packets_out, packets_out, struct tcp_sock); 6427 break; 6428 6429 case offsetof(struct bpf_sock_ops, retrans_out): 6430 SOCK_OPS_GET_FIELD(retrans_out, retrans_out, struct tcp_sock); 6431 break; 6432 6433 case offsetof(struct bpf_sock_ops, total_retrans): 6434 SOCK_OPS_GET_FIELD(total_retrans, total_retrans, 6435 struct tcp_sock); 6436 break; 6437 6438 case offsetof(struct bpf_sock_ops, segs_in): 6439 SOCK_OPS_GET_FIELD(segs_in, segs_in, struct tcp_sock); 6440 break; 6441 6442 case offsetof(struct bpf_sock_ops, data_segs_in): 6443 SOCK_OPS_GET_FIELD(data_segs_in, data_segs_in, struct tcp_sock); 6444 break; 6445 6446 case offsetof(struct bpf_sock_ops, segs_out): 6447 SOCK_OPS_GET_FIELD(segs_out, segs_out, struct tcp_sock); 6448 break; 6449 6450 case offsetof(struct bpf_sock_ops, data_segs_out): 6451 SOCK_OPS_GET_FIELD(data_segs_out, data_segs_out, 6452 struct tcp_sock); 6453 break; 6454 6455 case offsetof(struct bpf_sock_ops, lost_out): 6456 SOCK_OPS_GET_FIELD(lost_out, lost_out, struct tcp_sock); 6457 break; 6458 6459 case offsetof(struct bpf_sock_ops, sacked_out): 6460 SOCK_OPS_GET_FIELD(sacked_out, sacked_out, struct tcp_sock); 6461 break; 6462 6463 case offsetof(struct bpf_sock_ops, sk_txhash): 6464 SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash, 6465 struct sock, type); 6466 break; 6467 6468 case offsetof(struct bpf_sock_ops, bytes_received): 6469 SOCK_OPS_GET_FIELD(bytes_received, bytes_received, 6470 struct tcp_sock); 6471 break; 6472 6473 case offsetof(struct bpf_sock_ops, bytes_acked): 6474 SOCK_OPS_GET_FIELD(bytes_acked, bytes_acked, struct tcp_sock); 6475 break; 6476 6477 } 6478 return insn - insn_buf; 6479 } 6480 6481 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type, 6482 const struct bpf_insn *si, 6483 struct bpf_insn *insn_buf, 6484 struct bpf_prog *prog, u32 *target_size) 6485 { 6486 struct bpf_insn *insn = insn_buf; 6487 int off; 6488 6489 switch (si->off) { 6490 case offsetof(struct __sk_buff, data_end): 6491 off = si->off; 6492 off -= offsetof(struct __sk_buff, data_end); 6493 off += offsetof(struct sk_buff, cb); 6494 off += offsetof(struct tcp_skb_cb, bpf.data_end); 6495 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, 6496 si->src_reg, off); 6497 break; 6498 default: 6499 return bpf_convert_ctx_access(type, si, insn_buf, prog, 6500 target_size); 6501 } 6502 6503 return insn - insn_buf; 6504 } 6505 6506 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type, 6507 const struct bpf_insn *si, 6508 struct bpf_insn *insn_buf, 6509 struct bpf_prog *prog, u32 *target_size) 6510 { 6511 struct bpf_insn *insn = insn_buf; 6512 #if IS_ENABLED(CONFIG_IPV6) 6513 int off; 6514 #endif 6515 6516 switch (si->off) { 6517 case offsetof(struct sk_msg_md, data): 6518 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data), 6519 si->dst_reg, si->src_reg, 6520 offsetof(struct sk_msg_buff, data)); 6521 break; 6522 case offsetof(struct sk_msg_md, data_end): 6523 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data_end), 6524 si->dst_reg, si->src_reg, 6525 offsetof(struct sk_msg_buff, data_end)); 6526 break; 6527 case offsetof(struct sk_msg_md, family): 6528 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2); 6529 6530 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6531 struct sk_msg_buff, sk), 6532 si->dst_reg, si->src_reg, 6533 offsetof(struct sk_msg_buff, sk)); 6534 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6535 offsetof(struct sock_common, skc_family)); 6536 break; 6537 6538 case offsetof(struct sk_msg_md, remote_ip4): 6539 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4); 6540 6541 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6542 struct sk_msg_buff, sk), 6543 si->dst_reg, si->src_reg, 6544 offsetof(struct sk_msg_buff, sk)); 6545 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6546 offsetof(struct sock_common, skc_daddr)); 6547 break; 6548 6549 case offsetof(struct sk_msg_md, local_ip4): 6550 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6551 skc_rcv_saddr) != 4); 6552 6553 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6554 struct sk_msg_buff, sk), 6555 si->dst_reg, si->src_reg, 6556 offsetof(struct sk_msg_buff, sk)); 6557 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6558 offsetof(struct sock_common, 6559 skc_rcv_saddr)); 6560 break; 6561 6562 case offsetof(struct sk_msg_md, remote_ip6[0]) ... 6563 offsetof(struct sk_msg_md, remote_ip6[3]): 6564 #if IS_ENABLED(CONFIG_IPV6) 6565 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6566 skc_v6_daddr.s6_addr32[0]) != 4); 6567 6568 off = si->off; 6569 off -= offsetof(struct sk_msg_md, remote_ip6[0]); 6570 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6571 struct sk_msg_buff, sk), 6572 si->dst_reg, si->src_reg, 6573 offsetof(struct sk_msg_buff, sk)); 6574 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6575 offsetof(struct sock_common, 6576 skc_v6_daddr.s6_addr32[0]) + 6577 off); 6578 #else 6579 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6580 #endif 6581 break; 6582 6583 case offsetof(struct sk_msg_md, local_ip6[0]) ... 6584 offsetof(struct sk_msg_md, local_ip6[3]): 6585 #if IS_ENABLED(CONFIG_IPV6) 6586 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, 6587 skc_v6_rcv_saddr.s6_addr32[0]) != 4); 6588 6589 off = si->off; 6590 off -= offsetof(struct sk_msg_md, local_ip6[0]); 6591 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6592 struct sk_msg_buff, sk), 6593 si->dst_reg, si->src_reg, 6594 offsetof(struct sk_msg_buff, sk)); 6595 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, 6596 offsetof(struct sock_common, 6597 skc_v6_rcv_saddr.s6_addr32[0]) + 6598 off); 6599 #else 6600 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0); 6601 #endif 6602 break; 6603 6604 case offsetof(struct sk_msg_md, remote_port): 6605 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2); 6606 6607 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6608 struct sk_msg_buff, sk), 6609 si->dst_reg, si->src_reg, 6610 offsetof(struct sk_msg_buff, sk)); 6611 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6612 offsetof(struct sock_common, skc_dport)); 6613 #ifndef __BIG_ENDIAN_BITFIELD 6614 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16); 6615 #endif 6616 break; 6617 6618 case offsetof(struct sk_msg_md, local_port): 6619 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2); 6620 6621 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( 6622 struct sk_msg_buff, sk), 6623 si->dst_reg, si->src_reg, 6624 offsetof(struct sk_msg_buff, sk)); 6625 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg, 6626 offsetof(struct sock_common, skc_num)); 6627 break; 6628 } 6629 6630 return insn - insn_buf; 6631 } 6632 6633 const struct bpf_verifier_ops sk_filter_verifier_ops = { 6634 .get_func_proto = sk_filter_func_proto, 6635 .is_valid_access = sk_filter_is_valid_access, 6636 .convert_ctx_access = bpf_convert_ctx_access, 6637 .gen_ld_abs = bpf_gen_ld_abs, 6638 }; 6639 6640 const struct bpf_prog_ops sk_filter_prog_ops = { 6641 .test_run = bpf_prog_test_run_skb, 6642 }; 6643 6644 const struct bpf_verifier_ops tc_cls_act_verifier_ops = { 6645 .get_func_proto = tc_cls_act_func_proto, 6646 .is_valid_access = tc_cls_act_is_valid_access, 6647 .convert_ctx_access = tc_cls_act_convert_ctx_access, 6648 .gen_prologue = tc_cls_act_prologue, 6649 .gen_ld_abs = bpf_gen_ld_abs, 6650 }; 6651 6652 const struct bpf_prog_ops tc_cls_act_prog_ops = { 6653 .test_run = bpf_prog_test_run_skb, 6654 }; 6655 6656 const struct bpf_verifier_ops xdp_verifier_ops = { 6657 .get_func_proto = xdp_func_proto, 6658 .is_valid_access = xdp_is_valid_access, 6659 .convert_ctx_access = xdp_convert_ctx_access, 6660 }; 6661 6662 const struct bpf_prog_ops xdp_prog_ops = { 6663 .test_run = bpf_prog_test_run_xdp, 6664 }; 6665 6666 const struct bpf_verifier_ops cg_skb_verifier_ops = { 6667 .get_func_proto = sk_filter_func_proto, 6668 .is_valid_access = sk_filter_is_valid_access, 6669 .convert_ctx_access = bpf_convert_ctx_access, 6670 }; 6671 6672 const struct bpf_prog_ops cg_skb_prog_ops = { 6673 .test_run = bpf_prog_test_run_skb, 6674 }; 6675 6676 const struct bpf_verifier_ops lwt_in_verifier_ops = { 6677 .get_func_proto = lwt_in_func_proto, 6678 .is_valid_access = lwt_is_valid_access, 6679 .convert_ctx_access = bpf_convert_ctx_access, 6680 }; 6681 6682 const struct bpf_prog_ops lwt_in_prog_ops = { 6683 .test_run = bpf_prog_test_run_skb, 6684 }; 6685 6686 const struct bpf_verifier_ops lwt_out_verifier_ops = { 6687 .get_func_proto = lwt_out_func_proto, 6688 .is_valid_access = lwt_is_valid_access, 6689 .convert_ctx_access = bpf_convert_ctx_access, 6690 }; 6691 6692 const struct bpf_prog_ops lwt_out_prog_ops = { 6693 .test_run = bpf_prog_test_run_skb, 6694 }; 6695 6696 const struct bpf_verifier_ops lwt_xmit_verifier_ops = { 6697 .get_func_proto = lwt_xmit_func_proto, 6698 .is_valid_access = lwt_is_valid_access, 6699 .convert_ctx_access = bpf_convert_ctx_access, 6700 .gen_prologue = tc_cls_act_prologue, 6701 }; 6702 6703 const struct bpf_prog_ops lwt_xmit_prog_ops = { 6704 .test_run = bpf_prog_test_run_skb, 6705 }; 6706 6707 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = { 6708 .get_func_proto = lwt_seg6local_func_proto, 6709 .is_valid_access = lwt_is_valid_access, 6710 .convert_ctx_access = bpf_convert_ctx_access, 6711 }; 6712 6713 const struct bpf_prog_ops lwt_seg6local_prog_ops = { 6714 .test_run = bpf_prog_test_run_skb, 6715 }; 6716 6717 const struct bpf_verifier_ops cg_sock_verifier_ops = { 6718 .get_func_proto = sock_filter_func_proto, 6719 .is_valid_access = sock_filter_is_valid_access, 6720 .convert_ctx_access = sock_filter_convert_ctx_access, 6721 }; 6722 6723 const struct bpf_prog_ops cg_sock_prog_ops = { 6724 }; 6725 6726 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = { 6727 .get_func_proto = sock_addr_func_proto, 6728 .is_valid_access = sock_addr_is_valid_access, 6729 .convert_ctx_access = sock_addr_convert_ctx_access, 6730 }; 6731 6732 const struct bpf_prog_ops cg_sock_addr_prog_ops = { 6733 }; 6734 6735 const struct bpf_verifier_ops sock_ops_verifier_ops = { 6736 .get_func_proto = sock_ops_func_proto, 6737 .is_valid_access = sock_ops_is_valid_access, 6738 .convert_ctx_access = sock_ops_convert_ctx_access, 6739 }; 6740 6741 const struct bpf_prog_ops sock_ops_prog_ops = { 6742 }; 6743 6744 const struct bpf_verifier_ops sk_skb_verifier_ops = { 6745 .get_func_proto = sk_skb_func_proto, 6746 .is_valid_access = sk_skb_is_valid_access, 6747 .convert_ctx_access = sk_skb_convert_ctx_access, 6748 .gen_prologue = sk_skb_prologue, 6749 }; 6750 6751 const struct bpf_prog_ops sk_skb_prog_ops = { 6752 }; 6753 6754 const struct bpf_verifier_ops sk_msg_verifier_ops = { 6755 .get_func_proto = sk_msg_func_proto, 6756 .is_valid_access = sk_msg_is_valid_access, 6757 .convert_ctx_access = sk_msg_convert_ctx_access, 6758 }; 6759 6760 const struct bpf_prog_ops sk_msg_prog_ops = { 6761 }; 6762 6763 int sk_detach_filter(struct sock *sk) 6764 { 6765 int ret = -ENOENT; 6766 struct sk_filter *filter; 6767 6768 if (sock_flag(sk, SOCK_FILTER_LOCKED)) 6769 return -EPERM; 6770 6771 filter = rcu_dereference_protected(sk->sk_filter, 6772 lockdep_sock_is_held(sk)); 6773 if (filter) { 6774 RCU_INIT_POINTER(sk->sk_filter, NULL); 6775 sk_filter_uncharge(sk, filter); 6776 ret = 0; 6777 } 6778 6779 return ret; 6780 } 6781 EXPORT_SYMBOL_GPL(sk_detach_filter); 6782 6783 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf, 6784 unsigned int len) 6785 { 6786 struct sock_fprog_kern *fprog; 6787 struct sk_filter *filter; 6788 int ret = 0; 6789 6790 lock_sock(sk); 6791 filter = rcu_dereference_protected(sk->sk_filter, 6792 lockdep_sock_is_held(sk)); 6793 if (!filter) 6794 goto out; 6795 6796 /* We're copying the filter that has been originally attached, 6797 * so no conversion/decode needed anymore. eBPF programs that 6798 * have no original program cannot be dumped through this. 6799 */ 6800 ret = -EACCES; 6801 fprog = filter->prog->orig_prog; 6802 if (!fprog) 6803 goto out; 6804 6805 ret = fprog->len; 6806 if (!len) 6807 /* User space only enquires number of filter blocks. */ 6808 goto out; 6809 6810 ret = -EINVAL; 6811 if (len < fprog->len) 6812 goto out; 6813 6814 ret = -EFAULT; 6815 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog))) 6816 goto out; 6817 6818 /* Instead of bytes, the API requests to return the number 6819 * of filter blocks. 6820 */ 6821 ret = fprog->len; 6822 out: 6823 release_sock(sk); 6824 return ret; 6825 } 6826