1 /* $NetBSD: bpf_filter.c,v 1.74 2026/09/07 15:47:16 tls Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from the Stanford/CMU enet packet filter, 8 * (net/enet.c) distributed as part of 4.3BSD, and code contributed 9 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 10 * Berkeley Laboratory. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)bpf_filter.c 8.1 (Berkeley) 6/10/93 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: bpf_filter.c,v 1.74 2026/09/07 15:47:16 tls Exp $"); 41 42 #if 0 43 #if !(defined(lint) || defined(KERNEL)) 44 static const char rcsid[] = 45 "@(#) Header: bpf_filter.c,v 1.33 97/04/26 13:37:18 leres Exp (LBL)"; 46 #endif 47 #endif 48 49 #include <sys/param.h> 50 #include <sys/atomic.h> 51 52 #include <sys/time.h> 53 #include <sys/kmem.h> 54 #include <sys/endian.h> 55 56 #ifdef _KERNEL 57 #include <sys/module.h> 58 #endif 59 60 #define __BPF_PRIVATE 61 #include <net/bpf.h> 62 63 #ifdef _KERNEL 64 65 bpf_ctx_t * 66 bpf_create(void) 67 { 68 return kmem_zalloc(sizeof(bpf_ctx_t), KM_SLEEP); 69 } 70 71 void 72 bpf_destroy(bpf_ctx_t *bc) 73 { 74 kmem_free(bc, sizeof(bpf_ctx_t)); 75 } 76 77 int 78 bpf_set_cop(bpf_ctx_t *bc, const bpf_copfunc_t *funcs, size_t n) 79 { 80 bc->copfuncs = funcs; 81 bc->nfuncs = n; 82 return 0; 83 } 84 85 int 86 bpf_set_extmem(bpf_ctx_t *bc, size_t nwords, bpf_memword_init_t preinited) 87 { 88 if (nwords > BPF_MAX_MEMWORDS || (preinited >> nwords) != 0) { 89 return EINVAL; 90 } 91 bc->extwords = nwords; 92 bc->preinited = preinited; 93 return 0; 94 } 95 96 #endif 97 98 #define EXTRACT_SHORT(p) be16dec(p) 99 #define EXTRACT_LONG(p) be32dec(p) 100 101 #ifdef _KERNEL 102 #include <sys/mbuf.h> 103 #define MINDEX(len, m, k) \ 104 { \ 105 len = m->m_len; \ 106 while (k >= len) { \ 107 k -= len; \ 108 m = m->m_next; \ 109 if (m == 0) \ 110 return 0; \ 111 len = m->m_len; \ 112 } \ 113 } 114 115 uint32_t m_xword(const struct mbuf *, uint32_t, int *); 116 uint32_t m_xhalf(const struct mbuf *, uint32_t, int *); 117 uint32_t m_xbyte(const struct mbuf *, uint32_t, int *); 118 119 #define xword(p, k, err) m_xword((const struct mbuf *)(p), (k), (err)) 120 #define xhalf(p, k, err) m_xhalf((const struct mbuf *)(p), (k), (err)) 121 #define xbyte(p, k, err) m_xbyte((const struct mbuf *)(p), (k), (err)) 122 123 uint32_t 124 m_xword(const struct mbuf *m, uint32_t k, int *err) 125 { 126 int len; 127 u_char *cp, *np; 128 struct mbuf *m0; 129 130 *err = 1; 131 MINDEX(len, m, k); 132 cp = mtod(m, u_char *) + k; 133 if (len - k >= 4) { 134 *err = 0; 135 return EXTRACT_LONG(cp); 136 } 137 m0 = m->m_next; 138 if (m0 == 0 || (len - k) + m0->m_len < 4) 139 return 0; 140 *err = 0; 141 np = mtod(m0, u_char *); 142 143 switch (len - k) { 144 case 1: 145 return (cp[0] << 24) | (np[0] << 16) | (np[1] << 8) | np[2]; 146 case 2: 147 return (cp[0] << 24) | (cp[1] << 16) | (np[0] << 8) | np[1]; 148 default: 149 return (cp[0] << 24) | (cp[1] << 16) | (cp[2] << 8) | np[0]; 150 } 151 } 152 153 uint32_t 154 m_xhalf(const struct mbuf *m, uint32_t k, int *err) 155 { 156 int len; 157 u_char *cp; 158 struct mbuf *m0; 159 160 *err = 1; 161 MINDEX(len, m, k); 162 cp = mtod(m, u_char *) + k; 163 if (len - k >= 2) { 164 *err = 0; 165 return EXTRACT_SHORT(cp); 166 } 167 m0 = m->m_next; 168 if (m0 == 0) 169 return 0; 170 *err = 0; 171 return (cp[0] << 8) | mtod(m0, u_char *)[0]; 172 } 173 174 uint32_t 175 m_xbyte(const struct mbuf *m, uint32_t k, int *err) 176 { 177 int len; 178 179 *err = 1; 180 MINDEX(len, m, k); 181 *err = 0; 182 return mtod(m, u_char *)[k]; 183 } 184 #else /* _KERNEL */ 185 #include <stdlib.h> 186 #endif /* !_KERNEL */ 187 188 #include <net/bpf.h> 189 190 /* 191 * Execute the filter program starting at pc on the packet p 192 * wirelen is the length of the original packet 193 * buflen is the amount of data present 194 */ 195 #ifdef _KERNEL 196 197 u_int 198 bpf_filter(const struct bpf_insn *pc, const u_char *p, u_int wirelen, 199 u_int buflen) 200 { 201 uint32_t mem[BPF_MEMWORDS]; 202 bpf_args_t args = { 203 .pkt = p, 204 .wirelen = wirelen, 205 .buflen = buflen, 206 .mem = mem, 207 .arg = NULL 208 }; 209 210 return bpf_filter_ext(NULL, pc, &args); 211 } 212 213 u_int 214 bpf_filter_ext(const bpf_ctx_t *bc, const struct bpf_insn *pc, bpf_args_t *args) 215 #else 216 __strong_alias(pcapint_filter, bpf_filter) 217 u_int 218 bpf_filter(const struct bpf_insn *pc, const u_char *p, u_int wirelen, 219 u_int buflen) 220 #endif 221 { 222 uint32_t A, X, k; 223 #ifndef _KERNEL 224 uint32_t mem[BPF_MEMWORDS]; 225 bpf_args_t args_store = { 226 .pkt = p, 227 .wirelen = wirelen, 228 .buflen = buflen, 229 .mem = mem, 230 .arg = NULL 231 }; 232 bpf_args_t * const args = &args_store; 233 #else 234 const uint8_t * const p = args->pkt; 235 #endif 236 if (pc == 0) { 237 /* 238 * No filter means accept all. 239 */ 240 return (u_int)-1; 241 } 242 243 /* 244 * Note: safe to leave memwords uninitialised, as the validation 245 * step ensures that it will not be read, if it was not written. 246 */ 247 A = 0; 248 X = 0; 249 --pc; 250 251 for (;;) { 252 ++pc; 253 switch (pc->code) { 254 255 default: 256 #ifdef _KERNEL 257 return 0; 258 #else 259 abort(); 260 /*NOTREACHED*/ 261 #endif 262 case BPF_RET|BPF_K: 263 return (u_int)pc->k; 264 265 case BPF_RET|BPF_A: 266 return (u_int)A; 267 268 case BPF_LD|BPF_W|BPF_ABS: 269 k = pc->k; 270 if (k > args->buflen || 271 sizeof(int32_t) > args->buflen - k) { 272 #ifdef _KERNEL 273 int merr; 274 275 if (args->buflen != 0) 276 return 0; 277 A = xword(args->pkt, k, &merr); 278 if (merr != 0) 279 return 0; 280 continue; 281 #else 282 return 0; 283 #endif 284 } 285 A = EXTRACT_LONG(&p[k]); 286 continue; 287 288 case BPF_LD|BPF_H|BPF_ABS: 289 k = pc->k; 290 if (k > args->buflen || 291 sizeof(int16_t) > args->buflen - k) { 292 #ifdef _KERNEL 293 int merr; 294 295 if (args->buflen != 0) 296 return 0; 297 A = xhalf(args->pkt, k, &merr); 298 if (merr != 0) 299 return 0; 300 continue; 301 #else 302 return 0; 303 #endif 304 } 305 A = EXTRACT_SHORT(&p[k]); 306 continue; 307 308 case BPF_LD|BPF_B|BPF_ABS: 309 k = pc->k; 310 if (k >= args->buflen) { 311 #ifdef _KERNEL 312 int merr; 313 314 if (args->buflen != 0) 315 return 0; 316 A = xbyte(args->pkt, k, &merr); 317 if (merr != 0) 318 return 0; 319 continue; 320 #else 321 return 0; 322 #endif 323 } 324 A = p[k]; 325 continue; 326 327 case BPF_LD|BPF_W|BPF_LEN: 328 A = args->wirelen; 329 continue; 330 331 case BPF_LDX|BPF_W|BPF_LEN: 332 X = args->wirelen; 333 continue; 334 335 case BPF_LD|BPF_W|BPF_IND: 336 k = X + pc->k; 337 if (k < X || k >= args->buflen || 338 sizeof(int32_t) > args->buflen - k) { 339 #ifdef _KERNEL 340 int merr; 341 342 if (k < X || args->buflen != 0) 343 return 0; 344 A = xword(args->pkt, k, &merr); 345 if (merr != 0) 346 return 0; 347 continue; 348 #else 349 return 0; 350 #endif 351 } 352 A = EXTRACT_LONG(&p[k]); 353 continue; 354 355 case BPF_LD|BPF_H|BPF_IND: 356 k = X + pc->k; 357 if (k < X || k >= args->buflen || 358 sizeof(int16_t) > args->buflen - k) { 359 #ifdef _KERNEL 360 int merr; 361 362 if (k < X || args->buflen != 0) 363 return 0; 364 A = xhalf(args->pkt, k, &merr); 365 if (merr != 0) 366 return 0; 367 continue; 368 #else 369 return 0; 370 #endif 371 } 372 A = EXTRACT_SHORT(&p[k]); 373 continue; 374 375 case BPF_LD|BPF_B|BPF_IND: 376 k = X + pc->k; 377 if (k < X || k >= args->buflen) { 378 #ifdef _KERNEL 379 int merr; 380 381 if (k < X || args->buflen != 0) 382 return 0; 383 A = xbyte(args->pkt, k, &merr); 384 if (merr != 0) 385 return 0; 386 continue; 387 #else 388 return 0; 389 #endif 390 } 391 A = p[k]; 392 continue; 393 394 case BPF_LDX|BPF_MSH|BPF_B: 395 k = pc->k; 396 if (k >= args->buflen) { 397 #ifdef _KERNEL 398 int merr; 399 400 if (args->buflen != 0) 401 return 0; 402 X = (xbyte(args->pkt, k, &merr) & 0xf) << 2; 403 if (merr != 0) 404 return 0; 405 continue; 406 #else 407 return 0; 408 #endif 409 } 410 X = (p[pc->k] & 0xf) << 2; 411 continue; 412 413 case BPF_LD|BPF_IMM: 414 A = pc->k; 415 continue; 416 417 case BPF_LDX|BPF_IMM: 418 X = pc->k; 419 continue; 420 421 case BPF_LD|BPF_MEM: 422 A = args->mem[pc->k]; 423 continue; 424 425 case BPF_LDX|BPF_MEM: 426 X = args->mem[pc->k]; 427 continue; 428 429 case BPF_ST: 430 args->mem[pc->k] = A; 431 continue; 432 433 case BPF_STX: 434 args->mem[pc->k] = X; 435 continue; 436 437 case BPF_JMP|BPF_JA: 438 pc += pc->k; 439 continue; 440 441 case BPF_JMP|BPF_JGT|BPF_K: 442 pc += (A > pc->k) ? pc->jt : pc->jf; 443 continue; 444 445 case BPF_JMP|BPF_JGE|BPF_K: 446 pc += (A >= pc->k) ? pc->jt : pc->jf; 447 continue; 448 449 case BPF_JMP|BPF_JEQ|BPF_K: 450 pc += (A == pc->k) ? pc->jt : pc->jf; 451 continue; 452 453 case BPF_JMP|BPF_JSET|BPF_K: 454 pc += (A & pc->k) ? pc->jt : pc->jf; 455 continue; 456 457 case BPF_JMP|BPF_JGT|BPF_X: 458 pc += (A > X) ? pc->jt : pc->jf; 459 continue; 460 461 case BPF_JMP|BPF_JGE|BPF_X: 462 pc += (A >= X) ? pc->jt : pc->jf; 463 continue; 464 465 case BPF_JMP|BPF_JEQ|BPF_X: 466 pc += (A == X) ? pc->jt : pc->jf; 467 continue; 468 469 case BPF_JMP|BPF_JSET|BPF_X: 470 pc += (A & X) ? pc->jt : pc->jf; 471 continue; 472 473 case BPF_ALU|BPF_ADD|BPF_X: 474 A += X; 475 continue; 476 477 case BPF_ALU|BPF_SUB|BPF_X: 478 A -= X; 479 continue; 480 481 case BPF_ALU|BPF_MUL|BPF_X: 482 A *= X; 483 continue; 484 485 case BPF_ALU|BPF_DIV|BPF_X: 486 if (X == 0) 487 return 0; 488 A /= X; 489 continue; 490 491 case BPF_ALU|BPF_MOD|BPF_X: 492 if (X == 0) 493 return 0; 494 A %= X; 495 continue; 496 497 case BPF_ALU|BPF_AND|BPF_X: 498 A &= X; 499 continue; 500 501 case BPF_ALU|BPF_OR|BPF_X: 502 A |= X; 503 continue; 504 505 case BPF_ALU|BPF_XOR|BPF_X: 506 A ^= X; 507 continue; 508 509 case BPF_ALU|BPF_LSH|BPF_X: 510 A <<= X; 511 continue; 512 513 case BPF_ALU|BPF_RSH|BPF_X: 514 A >>= X; 515 continue; 516 517 case BPF_ALU|BPF_ADD|BPF_K: 518 A += pc->k; 519 continue; 520 521 case BPF_ALU|BPF_SUB|BPF_K: 522 A -= pc->k; 523 continue; 524 525 case BPF_ALU|BPF_MUL|BPF_K: 526 A *= pc->k; 527 continue; 528 529 case BPF_ALU|BPF_DIV|BPF_K: 530 A /= pc->k; 531 continue; 532 533 case BPF_ALU|BPF_MOD|BPF_K: 534 A %= pc->k; 535 continue; 536 537 case BPF_ALU|BPF_AND|BPF_K: 538 A &= pc->k; 539 continue; 540 541 case BPF_ALU|BPF_OR|BPF_K: 542 A |= pc->k; 543 continue; 544 545 case BPF_ALU|BPF_XOR|BPF_K: 546 A ^= pc->k; 547 continue; 548 549 case BPF_ALU|BPF_LSH|BPF_K: 550 A <<= pc->k; 551 continue; 552 553 case BPF_ALU|BPF_RSH|BPF_K: 554 A >>= pc->k; 555 continue; 556 557 case BPF_ALU|BPF_NEG: 558 A = -A; 559 continue; 560 561 case BPF_MISC|BPF_TAX: 562 X = A; 563 continue; 564 565 case BPF_MISC|BPF_TXA: 566 A = X; 567 continue; 568 569 case BPF_MISC|BPF_COP: 570 #ifdef _KERNEL 571 if (pc->k < bc->nfuncs) { 572 const bpf_copfunc_t fn = bc->copfuncs[pc->k]; 573 A = fn(bc, args, A); 574 continue; 575 } 576 #endif 577 return 0; 578 579 case BPF_MISC|BPF_COPX: 580 #ifdef _KERNEL 581 if (X < bc->nfuncs) { 582 const bpf_copfunc_t fn = bc->copfuncs[X]; 583 A = fn(bc, args, A); 584 continue; 585 } 586 #endif 587 return 0; 588 } 589 } 590 } 591 592 /* 593 * Return true if the 'fcode' is a valid filter program. 594 * The constraints are that each jump be forward and to a valid 595 * code, that memory accesses are within valid ranges (to the 596 * extent that this can be checked statically; loads of packet 597 * data have to be, and are, also checked at run time), and that 598 * the code terminates with either an accept or reject. 599 * 600 * The kernel needs to be able to verify an application's filter code. 601 * Otherwise, a bogus program could easily crash the system. 602 */ 603 604 #if defined(KERNEL) || defined(_KERNEL) 605 606 int 607 bpf_validate(const struct bpf_insn *f, int signed_len) 608 { 609 return bpf_validate_ext(NULL, f, signed_len); 610 } 611 612 int 613 bpf_validate_ext(const bpf_ctx_t *bc, const struct bpf_insn *f, int signed_len) 614 #else 615 __strong_alias(pcapint_validate_filter, bpf_validate) 616 int 617 bpf_validate(const struct bpf_insn *f, int signed_len) 618 #endif 619 { 620 u_int i, from, len, ok = 0; 621 const struct bpf_insn *p; 622 #if defined(KERNEL) || defined(_KERNEL) 623 bpf_memword_init_t *mem, invalid; 624 size_t size; 625 const size_t extwords = bc ? bc->extwords : 0; 626 const size_t memwords = extwords ? extwords : BPF_MEMWORDS; 627 const bpf_memword_init_t preinited = extwords ? bc->preinited : 0; 628 #else 629 const size_t memwords = BPF_MEMWORDS; 630 #endif 631 632 len = (u_int)signed_len; 633 if (len < 1) 634 return 0; 635 #if defined(KERNEL) || defined(_KERNEL) 636 if (len > BPF_MAXINSNS) 637 return 0; 638 #endif 639 if (f[len - 1].code != (BPF_RET|BPF_K) && 640 f[len - 1].code != (BPF_RET|BPF_A)) { 641 return 0; 642 } 643 644 #if defined(KERNEL) || defined(_KERNEL) 645 /* Note: only the pre-initialised is valid on startup */ 646 mem = kmem_zalloc(size = sizeof(*mem) * len, KM_SLEEP); 647 invalid = ~preinited; 648 #endif 649 650 for (i = 0; i < len; ++i) { 651 #if defined(KERNEL) || defined(_KERNEL) 652 /* blend in any invalid bits for current pc */ 653 invalid |= mem[i]; 654 #endif 655 p = &f[i]; 656 switch (BPF_CLASS(p->code)) { 657 /* 658 * Check that memory operations use valid addresses. 659 */ 660 case BPF_LD: 661 case BPF_LDX: 662 switch (BPF_MODE(p->code)) { 663 case BPF_MEM: 664 /* 665 * There's no maximum packet data size 666 * in userland. The runtime packet length 667 * check suffices. 668 */ 669 #if defined(KERNEL) || defined(_KERNEL) 670 /* 671 * More strict check with actual packet length 672 * is done runtime. 673 */ 674 if (p->k >= memwords) 675 goto out; 676 /* check for current memory invalid */ 677 if (invalid & BPF_MEMWORD_INIT(p->k)) 678 goto out; 679 #endif 680 break; 681 case BPF_ABS: 682 case BPF_IND: 683 case BPF_MSH: 684 case BPF_IMM: 685 case BPF_LEN: 686 break; 687 default: 688 goto out; 689 } 690 break; 691 case BPF_ST: 692 case BPF_STX: 693 if (p->k >= memwords) 694 goto out; 695 #if defined(KERNEL) || defined(_KERNEL) 696 /* validate the memory word */ 697 invalid &= ~BPF_MEMWORD_INIT(p->k); 698 #endif 699 break; 700 case BPF_ALU: 701 switch (BPF_OP(p->code)) { 702 case BPF_ADD: 703 case BPF_SUB: 704 case BPF_MUL: 705 case BPF_OR: 706 case BPF_XOR: 707 case BPF_AND: 708 case BPF_LSH: 709 case BPF_RSH: 710 case BPF_NEG: 711 break; 712 case BPF_DIV: 713 case BPF_MOD: 714 /* 715 * Check for constant division by 0. 716 */ 717 if (BPF_SRC(p->code) == BPF_K && p->k == 0) 718 goto out; 719 break; 720 default: 721 goto out; 722 } 723 break; 724 case BPF_JMP: 725 /* 726 * Check that jumps are within the code block, 727 * and that unconditional branches don't go 728 * backwards as a result of an overflow. 729 * Unconditional branches have a 32-bit offset, 730 * so they could overflow; we check to make 731 * sure they don't. Conditional branches have 732 * an 8-bit offset, and the from address is <= 733 * BPF_MAXINSNS, and we assume that BPF_MAXINSNS 734 * is sufficiently small that adding 255 to it 735 * won't overflow. 736 * 737 * We know that len is <= BPF_MAXINSNS, and we 738 * assume that BPF_MAXINSNS is < the maximum size 739 * of a u_int, so that i + 1 doesn't overflow. 740 * 741 * For userland, we don't know that the from 742 * or len are <= BPF_MAXINSNS, but we know that 743 * from <= len, and, except on a 64-bit system, 744 * it's unlikely that len, if it truly reflects 745 * the size of the program we've been handed, 746 * will be anywhere near the maximum size of 747 * a u_int. We also don't check for backward 748 * branches, as we currently support them in 749 * userland for the protochain operation. 750 */ 751 from = i + 1; 752 switch (BPF_OP(p->code)) { 753 case BPF_JA: 754 if (from + p->k >= len) 755 goto out; 756 #if defined(KERNEL) || defined(_KERNEL) 757 if (from + p->k < from) 758 goto out; 759 /* 760 * mark the currently invalid bits for the 761 * destination 762 */ 763 mem[from + p->k] |= invalid; 764 invalid = 0; 765 #endif 766 break; 767 case BPF_JEQ: 768 case BPF_JGT: 769 case BPF_JGE: 770 case BPF_JSET: 771 if (from + p->jt >= len || from + p->jf >= len) 772 goto out; 773 #if defined(KERNEL) || defined(_KERNEL) 774 /* 775 * mark the currently invalid bits for both 776 * possible jump destinations 777 */ 778 mem[from + p->jt] |= invalid; 779 mem[from + p->jf] |= invalid; 780 invalid = 0; 781 #endif 782 break; 783 default: 784 goto out; 785 } 786 break; 787 case BPF_RET: 788 break; 789 case BPF_MISC: 790 switch (BPF_MISCOP(p->code)) { 791 case BPF_COP: 792 case BPF_COPX: 793 /* In-kernel COP use only. */ 794 #if defined(KERNEL) || defined(_KERNEL) 795 if (bc == NULL || bc->copfuncs == NULL) 796 goto out; 797 if (BPF_MISCOP(p->code) == BPF_COP && 798 p->k >= bc->nfuncs) { 799 goto out; 800 } 801 break; 802 #else 803 goto out; 804 #endif 805 default: 806 break; 807 } 808 break; 809 default: 810 goto out; 811 } 812 } 813 ok = 1; 814 out: 815 #if defined(KERNEL) || defined(_KERNEL) 816 kmem_free(mem, size); 817 #endif 818 return ok; 819 } 820 821 #ifdef _KERNEL 822 /* 823 * bpfjit is used by other in-kernel callers, such as npf, so define 824 * its hooks and accessors here, not in the bpf.c device node interface. 825 */ 826 struct bpfjit_ops bpfjit_module_ops = { 827 .bj_generate_code = NULL, 828 .bj_free_code = NULL 829 }; 830 831 bpfjit_func_t 832 bpf_jit_generate(bpf_ctx_t *bc, void *code, size_t size) 833 { 834 struct bpfjit_ops *ops = &bpfjit_module_ops; 835 bpfjit_func_t (*generate_code)(const bpf_ctx_t *, 836 const struct bpf_insn *, size_t); 837 838 generate_code = atomic_load_acquire(&ops->bj_generate_code); 839 if (generate_code != NULL) { 840 return generate_code(bc, code, size); 841 } 842 return NULL; 843 } 844 845 void 846 bpf_jit_freecode(bpfjit_func_t jcode) 847 { 848 KASSERT(bpfjit_module_ops.bj_free_code != NULL); 849 bpfjit_module_ops.bj_free_code(jcode); 850 } 851 #endif 852 853 /* Kernel module interface */ 854 855 #ifdef _KERNEL 856 MODULE(MODULE_CLASS_MISC, bpf_filter, NULL); 857 858 static int 859 bpf_filter_modcmd(modcmd_t cmd, void *opaque) 860 { 861 862 switch (cmd) { 863 case MODULE_CMD_INIT: 864 case MODULE_CMD_FINI: 865 return 0; 866 default: 867 return ENOTTY; 868 } 869 } 870 #endif 871
Indexes created Tue Sep 08 00:25:21 UTC 2026