| 1 | /*#define CHASE_CHAIN*/ |
| 2 | /* |
| 3 | * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998 |
| 4 | * The Regents of the University of California. All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that: (1) source code distributions |
| 8 | * retain the above copyright notice and this paragraph in its entirety, (2) |
| 9 | * distributions including binary code include the above copyright notice and |
| 10 | * this paragraph in its entirety in the documentation or other materials |
| 11 | * provided with the distribution, and (3) all advertising materials mentioning |
| 12 | * features or use of this software display the following acknowledgement: |
| 13 | * ``This product includes software developed by the University of California, |
| 14 | * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| 15 | * the University nor the names of its contributors may be used to endorse |
| 16 | * or promote products derived from this software without specific prior |
| 17 | * written permission. |
| 18 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| 19 | * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| 20 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 21 | */ |
| 22 | #ifndef lint |
| 23 | static const char rcsid[] _U_ = |
| 24 | "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.309 2008-12-23 20:13:29 guy Exp $ (LBL)"; |
| 25 | #endif |
| 26 | |
| 27 | #ifdef HAVE_CONFIG_H |
| 28 | #include "config.h" |
| 29 | #endif |
| 30 | |
| 31 | #ifdef WIN32 |
| 32 | #include <pcap-stdinc.h> |
| 33 | #else /* WIN32 */ |
| 34 | #if HAVE_INTTYPES_H |
| 35 | #include <inttypes.h> |
| 36 | #elif HAVE_STDINT_H |
| 37 | #include <stdint.h> |
| 38 | #endif |
| 39 | #ifdef HAVE_SYS_BITYPES_H |
| 40 | #include <sys/bitypes.h> |
| 41 | #endif |
| 42 | #include <sys/types.h> |
| 43 | #include <sys/socket.h> |
| 44 | #endif /* WIN32 */ |
| 45 | |
| 46 | /* |
| 47 | * XXX - why was this included even on UNIX? |
| 48 | */ |
| 49 | #ifdef __MINGW32__ |
| 50 | #include "ip6_misc.h" |
| 51 | #endif |
| 52 | |
| 53 | #ifndef WIN32 |
| 54 | |
| 55 | #ifdef __NetBSD__ |
| 56 | #include <sys/param.h> |
| 57 | #endif |
| 58 | |
| 59 | #include <netinet/in.h> |
| 60 | #include <arpa/inet.h> |
| 61 | |
| 62 | #endif /* WIN32 */ |
| 63 | |
| 64 | #include <stdlib.h> |
| 65 | #include <string.h> |
| 66 | #include <memory.h> |
| 67 | #include <setjmp.h> |
| 68 | #include <stdarg.h> |
| 69 | |
| 70 | #ifdef MSDOS |
| 71 | #include "pcap-dos.h" |
| 72 | #endif |
| 73 | |
| 74 | #include "pcap-int.h" |
| 75 | |
| 76 | #include "ethertype.h" |
| 77 | #include "nlpid.h" |
| 78 | #include "llc.h" |
| 79 | #include "gencode.h" |
| 80 | #include "ieee80211.h" |
| 81 | #include "atmuni31.h" |
| 82 | #include "sunatmpos.h" |
| 83 | #include "ppp.h" |
| 84 | #include "pcap/sll.h" |
| 85 | #include "pcap/ipnet.h" |
| 86 | #include "arcnet.h" |
| 87 | #ifdef HAVE_NET_PFVAR_H |
| 88 | #include <sys/socket.h> |
| 89 | #include <net/if.h> |
| 90 | #include <net/pf/pfvar.h> |
| 91 | #include <net/pf/if_pflog.h> |
| 92 | #endif |
| 93 | #ifndef offsetof |
| 94 | #define offsetof(s, e) ((size_t)&((s *)0)->e) |
| 95 | #endif |
| 96 | #ifdef INET6 |
| 97 | #ifndef WIN32 |
| 98 | #include <netdb.h> /* for "struct addrinfo" */ |
| 99 | #endif /* WIN32 */ |
| 100 | #endif /*INET6*/ |
| 101 | #include <pcap/namedb.h> |
| 102 | |
| 103 | #define ETHERMTU 1500 |
| 104 | |
| 105 | #ifndef IPPROTO_SCTP |
| 106 | #define IPPROTO_SCTP 132 |
| 107 | #endif |
| 108 | |
| 109 | #ifdef HAVE_OS_PROTO_H |
| 110 | #include "os-proto.h" |
| 111 | #endif |
| 112 | |
| 113 | #define JMP(c) ((c)|BPF_JMP|BPF_K) |
| 114 | |
| 115 | /* Locals */ |
| 116 | static jmp_buf top_ctx; |
| 117 | static pcap_t *bpf_pcap; |
| 118 | |
| 119 | /* Hack for updating VLAN, MPLS, and PPPoE offsets. */ |
| 120 | #ifdef WIN32 |
| 121 | static u_int orig_linktype = (u_int)-1, orig_nl = (u_int)-1, label_stack_depth = (u_int)-1; |
| 122 | #else |
| 123 | static u_int orig_linktype = -1U, orig_nl = -1U, label_stack_depth = -1U; |
| 124 | #endif |
| 125 | |
| 126 | /* XXX */ |
| 127 | #ifdef PCAP_FDDIPAD |
| 128 | static int pcap_fddipad; |
| 129 | #endif |
| 130 | |
| 131 | /* VARARGS */ |
| 132 | void |
| 133 | bpf_error(const char *fmt, ...) |
| 134 | { |
| 135 | va_list ap; |
| 136 | |
| 137 | va_start(ap, fmt); |
| 138 | if (bpf_pcap != NULL) |
| 139 | (void)vsnprintf(pcap_geterr(bpf_pcap), PCAP_ERRBUF_SIZE, |
| 140 | fmt, ap); |
| 141 | va_end(ap); |
| 142 | longjmp(top_ctx, 1); |
| 143 | /* NOTREACHED */ |
| 144 | } |
| 145 | |
| 146 | static void init_linktype(pcap_t *); |
| 147 | |
| 148 | static void init_regs(void); |
| 149 | static int alloc_reg(void); |
| 150 | static void free_reg(int); |
| 151 | |
| 152 | static struct block *root; |
| 153 | |
| 154 | /* |
| 155 | * Value passed to gen_load_a() to indicate what the offset argument |
| 156 | * is relative to. |
| 157 | */ |
| 158 | enum e_offrel { |
| 159 | OR_PACKET, /* relative to the beginning of the packet */ |
| 160 | OR_LINK, /* relative to the beginning of the link-layer header */ |
| 161 | OR_MACPL, /* relative to the end of the MAC-layer header */ |
| 162 | OR_NET, /* relative to the network-layer header */ |
| 163 | OR_NET_NOSNAP, /* relative to the network-layer header, with no SNAP header at the link layer */ |
| 164 | OR_TRAN_IPV4, /* relative to the transport-layer header, with IPv4 network layer */ |
| 165 | OR_TRAN_IPV6 /* relative to the transport-layer header, with IPv6 network layer */ |
| 166 | }; |
| 167 | |
| 168 | #ifdef INET6 |
| 169 | /* |
| 170 | * As errors are handled by a longjmp, anything allocated must be freed |
| 171 | * in the longjmp handler, so it must be reachable from that handler. |
| 172 | * One thing that's allocated is the result of pcap_nametoaddrinfo(); |
| 173 | * it must be freed with freeaddrinfo(). This variable points to any |
| 174 | * addrinfo structure that would need to be freed. |
| 175 | */ |
| 176 | static struct addrinfo *ai; |
| 177 | #endif |
| 178 | |
| 179 | /* |
| 180 | * We divy out chunks of memory rather than call malloc each time so |
| 181 | * we don't have to worry about leaking memory. It's probably |
| 182 | * not a big deal if all this memory was wasted but if this ever |
| 183 | * goes into a library that would probably not be a good idea. |
| 184 | * |
| 185 | * XXX - this *is* in a library.... |
| 186 | */ |
| 187 | #define NCHUNKS 16 |
| 188 | #define CHUNK0SIZE 1024 |
| 189 | struct chunk { |
| 190 | u_int n_left; |
| 191 | void *m; |
| 192 | }; |
| 193 | |
| 194 | static struct chunk chunks[NCHUNKS]; |
| 195 | static int cur_chunk; |
| 196 | |
| 197 | static void *newchunk(u_int); |
| 198 | static void freechunks(void); |
| 199 | static inline struct block *new_block(int); |
| 200 | static inline struct slist *new_stmt(int); |
| 201 | static struct block *gen_retblk(int); |
| 202 | static inline void syntax(void); |
| 203 | |
| 204 | static void backpatch(struct block *, struct block *); |
| 205 | static void merge(struct block *, struct block *); |
| 206 | static struct block *gen_cmp(enum e_offrel, u_int, u_int, bpf_int32); |
| 207 | static struct block *gen_cmp_gt(enum e_offrel, u_int, u_int, bpf_int32); |
| 208 | static struct block *gen_cmp_ge(enum e_offrel, u_int, u_int, bpf_int32); |
| 209 | static struct block *gen_cmp_lt(enum e_offrel, u_int, u_int, bpf_int32); |
| 210 | static struct block *gen_cmp_le(enum e_offrel, u_int, u_int, bpf_int32); |
| 211 | static struct block *gen_mcmp(enum e_offrel, u_int, u_int, bpf_int32, |
| 212 | bpf_u_int32); |
| 213 | static struct block *gen_bcmp(enum e_offrel, u_int, u_int, const u_char *); |
| 214 | static struct block *gen_ncmp(enum e_offrel, bpf_u_int32, bpf_u_int32, |
| 215 | bpf_u_int32, bpf_u_int32, int, bpf_int32); |
| 216 | static struct slist *gen_load_llrel(u_int, u_int); |
| 217 | static struct slist *gen_load_macplrel(u_int, u_int); |
| 218 | static struct slist *gen_load_a(enum e_offrel, u_int, u_int); |
| 219 | static struct slist *gen_loadx_iphdrlen(void); |
| 220 | static struct block *gen_uncond(int); |
| 221 | static inline struct block *gen_true(void); |
| 222 | static inline struct block *gen_false(void); |
| 223 | static struct block *gen_ether_linktype(int); |
| 224 | static struct block *gen_ipnet_linktype(int); |
| 225 | static struct block *gen_linux_sll_linktype(int); |
| 226 | static struct slist *gen_load_prism_llprefixlen(void); |
| 227 | static struct slist *gen_load_avs_llprefixlen(void); |
| 228 | static struct slist *gen_load_radiotap_llprefixlen(void); |
| 229 | static struct slist *gen_load_ppi_llprefixlen(void); |
| 230 | static void insert_compute_vloffsets(struct block *); |
| 231 | static struct slist *gen_llprefixlen(void); |
| 232 | static struct slist *gen_off_macpl(void); |
| 233 | static int ethertype_to_ppptype(int); |
| 234 | static struct block *gen_linktype(int); |
| 235 | static struct block *gen_snap(bpf_u_int32, bpf_u_int32); |
| 236 | static struct block *gen_llc_linktype(int); |
| 237 | static struct block *gen_hostop(bpf_u_int32, bpf_u_int32, int, int, u_int, u_int); |
| 238 | #ifdef INET6 |
| 239 | static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int); |
| 240 | #endif |
| 241 | static struct block *gen_ahostop(const u_char *, int); |
| 242 | static struct block *gen_ehostop(const u_char *, int); |
| 243 | static struct block *gen_fhostop(const u_char *, int); |
| 244 | static struct block *gen_thostop(const u_char *, int); |
| 245 | static struct block *gen_wlanhostop(const u_char *, int); |
| 246 | static struct block *gen_ipfchostop(const u_char *, int); |
| 247 | static struct block *gen_dnhostop(bpf_u_int32, int); |
| 248 | static struct block *gen_mpls_linktype(int); |
| 249 | static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int, int); |
| 250 | #ifdef INET6 |
| 251 | static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int, int); |
| 252 | #endif |
| 253 | #ifndef INET6 |
| 254 | static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int); |
| 255 | #endif |
| 256 | static struct block *gen_ipfrag(void); |
| 257 | static struct block *gen_portatom(int, bpf_int32); |
| 258 | static struct block *gen_portrangeatom(int, bpf_int32, bpf_int32); |
| 259 | #ifdef INET6 |
| 260 | static struct block *gen_portatom6(int, bpf_int32); |
| 261 | static struct block *gen_portrangeatom6(int, bpf_int32, bpf_int32); |
| 262 | #endif |
| 263 | struct block *gen_portop(int, int, int); |
| 264 | static struct block *gen_port(int, int, int); |
| 265 | struct block *gen_portrangeop(int, int, int, int); |
| 266 | static struct block *gen_portrange(int, int, int, int); |
| 267 | #ifdef INET6 |
| 268 | struct block *gen_portop6(int, int, int); |
| 269 | static struct block *gen_port6(int, int, int); |
| 270 | struct block *gen_portrangeop6(int, int, int, int); |
| 271 | static struct block *gen_portrange6(int, int, int, int); |
| 272 | #endif |
| 273 | static int lookup_proto(const char *, int); |
| 274 | static struct block *gen_protochain(int, int, int); |
| 275 | static struct block *gen_proto(int, int, int); |
| 276 | static struct slist *xfer_to_x(struct arth *); |
| 277 | static struct slist *xfer_to_a(struct arth *); |
| 278 | static struct block *gen_mac_multicast(int); |
| 279 | static struct block *gen_len(int, int); |
| 280 | static struct block *gen_check_802_11_data_frame(void); |
| 281 | |
| 282 | static struct block *gen_ppi_dlt_check(void); |
| 283 | static struct block *gen_msg_abbrev(int type); |
| 284 | |
| 285 | static void * |
| 286 | newchunk(n) |
| 287 | u_int n; |
| 288 | { |
| 289 | struct chunk *cp; |
| 290 | int k; |
| 291 | size_t size; |
| 292 | |
| 293 | #ifndef __NetBSD__ |
| 294 | /* XXX Round up to nearest long. */ |
| 295 | n = (n + sizeof(long) - 1) & ~(sizeof(long) - 1); |
| 296 | #else |
| 297 | /* XXX Round up to structure boundary. */ |
| 298 | n = ALIGN(n); |
| 299 | #endif |
| 300 | |
| 301 | cp = &chunks[cur_chunk]; |
| 302 | if (n > cp->n_left) { |
| 303 | ++cp, k = ++cur_chunk; |
| 304 | if (k >= NCHUNKS) |
| 305 | bpf_error("out of memory"); |
| 306 | size = CHUNK0SIZE << k; |
| 307 | cp->m = (void *)malloc(size); |
| 308 | if (cp->m == NULL) |
| 309 | bpf_error("out of memory"); |
| 310 | memset((char *)cp->m, 0, size); |
| 311 | cp->n_left = size; |
| 312 | if (n > size) |
| 313 | bpf_error("out of memory"); |
| 314 | } |
| 315 | cp->n_left -= n; |
| 316 | return (void *)((char *)cp->m + cp->n_left); |
| 317 | } |
| 318 | |
| 319 | static void |
| 320 | freechunks() |
| 321 | { |
| 322 | int i; |
| 323 | |
| 324 | cur_chunk = 0; |
| 325 | for (i = 0; i < NCHUNKS; ++i) |
| 326 | if (chunks[i].m != NULL) { |
| 327 | free(chunks[i].m); |
| 328 | chunks[i].m = NULL; |
| 329 | } |
| 330 | } |
| 331 | |
| 332 | /* |
| 333 | * A strdup whose allocations are freed after code generation is over. |
| 334 | */ |
| 335 | char * |
| 336 | sdup(s) |
| 337 | register const char *s; |
| 338 | { |
| 339 | int n = strlen(s) + 1; |
| 340 | char *cp = newchunk(n); |
| 341 | |
| 342 | strlcpy(cp, s, n); |
| 343 | return (cp); |
| 344 | } |
| 345 | |
| 346 | static inline struct block * |
| 347 | new_block(code) |
| 348 | int code; |
| 349 | { |
| 350 | struct block *p; |
| 351 | |
| 352 | p = (struct block *)newchunk(sizeof(*p)); |
| 353 | p->s.code = code; |
| 354 | p->head = p; |
| 355 | |
| 356 | return p; |
| 357 | } |
| 358 | |
| 359 | static inline struct slist * |
| 360 | new_stmt(code) |
| 361 | int code; |
| 362 | { |
| 363 | struct slist *p; |
| 364 | |
| 365 | p = (struct slist *)newchunk(sizeof(*p)); |
| 366 | p->s.code = code; |
| 367 | |
| 368 | return p; |
| 369 | } |
| 370 | |
| 371 | static struct block * |
| 372 | gen_retblk(v) |
| 373 | int v; |
| 374 | { |
| 375 | struct block *b = new_block(BPF_RET|BPF_K); |
| 376 | |
| 377 | b->s.k = v; |
| 378 | return b; |
| 379 | } |
| 380 | |
| 381 | static inline void |
| 382 | syntax() |
| 383 | { |
| 384 | bpf_error("syntax error in filter expression"); |
| 385 | } |
| 386 | |
| 387 | static bpf_u_int32 netmask; |
| 388 | static int snaplen; |
| 389 | int no_optimize; |
| 390 | #ifdef WIN32 |
| 391 | static int |
| 392 | pcap_compile_unsafe(pcap_t *p, struct bpf_program *program, |
| 393 | const char *buf, int optimize, bpf_u_int32 mask); |
| 394 | |
| 395 | int |
| 396 | pcap_compile(pcap_t *p, struct bpf_program *program, |
| 397 | const char *buf, int optimize, bpf_u_int32 mask) |
| 398 | { |
| 399 | int result; |
| 400 | |
| 401 | EnterCriticalSection(&g_PcapCompileCriticalSection); |
| 402 | |
| 403 | result = pcap_compile_unsafe(p, program, buf, optimize, mask); |
| 404 | |
| 405 | LeaveCriticalSection(&g_PcapCompileCriticalSection); |
| 406 | |
| 407 | return result; |
| 408 | } |
| 409 | |
| 410 | static int |
| 411 | pcap_compile_unsafe(pcap_t *p, struct bpf_program *program, |
| 412 | const char *buf, int optimize, bpf_u_int32 mask) |
| 413 | #else /* WIN32 */ |
| 414 | int |
| 415 | pcap_compile(pcap_t *p, struct bpf_program *program, |
| 416 | const char *buf, int optimize, bpf_u_int32 mask) |
| 417 | #endif /* WIN32 */ |
| 418 | { |
| 419 | extern int n_errors; |
| 420 | const char * volatile xbuf = buf; |
| 421 | int len; |
| 422 | |
| 423 | no_optimize = 0; |
| 424 | n_errors = 0; |
| 425 | root = NULL; |
| 426 | bpf_pcap = p; |
| 427 | init_regs(); |
| 428 | if (setjmp(top_ctx)) { |
| 429 | #ifdef INET6 |
| 430 | if (ai != NULL) { |
| 431 | freeaddrinfo(ai); |
| 432 | ai = NULL; |
| 433 | } |
| 434 | #endif |
| 435 | lex_cleanup(); |
| 436 | freechunks(); |
| 437 | return (-1); |
| 438 | } |
| 439 | |
| 440 | netmask = mask; |
| 441 | |
| 442 | snaplen = pcap_snapshot(p); |
| 443 | if (snaplen == 0) { |
| 444 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| 445 | "snaplen of 0 rejects all packets"); |
| 446 | return -1; |
| 447 | } |
| 448 | |
| 449 | lex_init(xbuf ? xbuf : ""); |
| 450 | init_linktype(p); |
| 451 | (void)pcap_parse(); |
| 452 | |
| 453 | if (n_errors) |
| 454 | syntax(); |
| 455 | |
| 456 | if (root == NULL) |
| 457 | root = gen_retblk(snaplen); |
| 458 | |
| 459 | if (optimize && !no_optimize) { |
| 460 | bpf_optimize(&root); |
| 461 | if (root == NULL || |
| 462 | (root->s.code == (BPF_RET|BPF_K) && root->s.k == 0)) |
| 463 | bpf_error("expression rejects all packets"); |
| 464 | } |
| 465 | program->bf_insns = icode_to_fcode(root, &len); |
| 466 | program->bf_len = len; |
| 467 | |
| 468 | lex_cleanup(); |
| 469 | freechunks(); |
| 470 | return (0); |
| 471 | } |
| 472 | |
| 473 | /* |
| 474 | * entry point for using the compiler with no pcap open |
| 475 | * pass in all the stuff that is needed explicitly instead. |
| 476 | */ |
| 477 | int |
| 478 | pcap_compile_nopcap(int snaplen_arg, int linktype_arg, |
| 479 | struct bpf_program *program, |
| 480 | const char *buf, int optimize, bpf_u_int32 mask) |
| 481 | { |
| 482 | pcap_t *p; |
| 483 | int ret; |
| 484 | |
| 485 | p = pcap_open_dead(linktype_arg, snaplen_arg); |
| 486 | if (p == NULL) |
| 487 | return (-1); |
| 488 | ret = pcap_compile(p, program, buf, optimize, mask); |
| 489 | pcap_close(p); |
| 490 | return (ret); |
| 491 | } |
| 492 | |
| 493 | /* |
| 494 | * Clean up a "struct bpf_program" by freeing all the memory allocated |
| 495 | * in it. |
| 496 | */ |
| 497 | void |
| 498 | pcap_freecode(struct bpf_program *program) |
| 499 | { |
| 500 | program->bf_len = 0; |
| 501 | if (program->bf_insns != NULL) { |
| 502 | free((char *)program->bf_insns); |
| 503 | program->bf_insns = NULL; |
| 504 | } |
| 505 | } |
| 506 | |
| 507 | /* |
| 508 | * Backpatch the blocks in 'list' to 'target'. The 'sense' field indicates |
| 509 | * which of the jt and jf fields has been resolved and which is a pointer |
| 510 | * back to another unresolved block (or nil). At least one of the fields |
| 511 | * in each block is already resolved. |
| 512 | */ |
| 513 | static void |
| 514 | backpatch(list, target) |
| 515 | struct block *list, *target; |
| 516 | { |
| 517 | struct block *next; |
| 518 | |
| 519 | while (list) { |
| 520 | if (!list->sense) { |
| 521 | next = JT(list); |
| 522 | JT(list) = target; |
| 523 | } else { |
| 524 | next = JF(list); |
| 525 | JF(list) = target; |
| 526 | } |
| 527 | list = next; |
| 528 | } |
| 529 | } |
| 530 | |
| 531 | /* |
| 532 | * Merge the lists in b0 and b1, using the 'sense' field to indicate |
| 533 | * which of jt and jf is the link. |
| 534 | */ |
| 535 | static void |
| 536 | merge(b0, b1) |
| 537 | struct block *b0, *b1; |
| 538 | { |
| 539 | register struct block **p = &b0; |
| 540 | |
| 541 | /* Find end of list. */ |
| 542 | while (*p) |
| 543 | p = !((*p)->sense) ? &JT(*p) : &JF(*p); |
| 544 | |
| 545 | /* Concatenate the lists. */ |
| 546 | *p = b1; |
| 547 | } |
| 548 | |
| 549 | void |
| 550 | finish_parse(p) |
| 551 | struct block *p; |
| 552 | { |
| 553 | struct block *ppi_dlt_check; |
| 554 | |
| 555 | /* |
| 556 | * Insert before the statements of the first (root) block any |
| 557 | * statements needed to load the lengths of any variable-length |
| 558 | * headers into registers. |
| 559 | * |
| 560 | * XXX - a fancier strategy would be to insert those before the |
| 561 | * statements of all blocks that use those lengths and that |
| 562 | * have no predecessors that use them, so that we only compute |
| 563 | * the lengths if we need them. There might be even better |
| 564 | * approaches than that. |
| 565 | * |
| 566 | * However, those strategies would be more complicated, and |
| 567 | * as we don't generate code to compute a length if the |
| 568 | * program has no tests that use the length, and as most |
| 569 | * tests will probably use those lengths, we would just |
| 570 | * postpone computing the lengths so that it's not done |
| 571 | * for tests that fail early, and it's not clear that's |
| 572 | * worth the effort. |
| 573 | */ |
| 574 | insert_compute_vloffsets(p->head); |
| 575 | |
| 576 | /* |
| 577 | * For DLT_PPI captures, generate a check of the per-packet |
| 578 | * DLT value to make sure it's DLT_IEEE802_11. |
| 579 | */ |
| 580 | ppi_dlt_check = gen_ppi_dlt_check(); |
| 581 | if (ppi_dlt_check != NULL) |
| 582 | gen_and(ppi_dlt_check, p); |
| 583 | |
| 584 | backpatch(p, gen_retblk(snaplen)); |
| 585 | p->sense = !p->sense; |
| 586 | backpatch(p, gen_retblk(0)); |
| 587 | root = p->head; |
| 588 | } |
| 589 | |
| 590 | void |
| 591 | gen_and(b0, b1) |
| 592 | struct block *b0, *b1; |
| 593 | { |
| 594 | backpatch(b0, b1->head); |
| 595 | b0->sense = !b0->sense; |
| 596 | b1->sense = !b1->sense; |
| 597 | merge(b1, b0); |
| 598 | b1->sense = !b1->sense; |
| 599 | b1->head = b0->head; |
| 600 | } |
| 601 | |
| 602 | void |
| 603 | gen_or(b0, b1) |
| 604 | struct block *b0, *b1; |
| 605 | { |
| 606 | b0->sense = !b0->sense; |
| 607 | backpatch(b0, b1->head); |
| 608 | b0->sense = !b0->sense; |
| 609 | merge(b1, b0); |
| 610 | b1->head = b0->head; |
| 611 | } |
| 612 | |
| 613 | void |
| 614 | gen_not(b) |
| 615 | struct block *b; |
| 616 | { |
| 617 | b->sense = !b->sense; |
| 618 | } |
| 619 | |
| 620 | static struct block * |
| 621 | gen_cmp(offrel, offset, size, v) |
| 622 | enum e_offrel offrel; |
| 623 | u_int offset, size; |
| 624 | bpf_int32 v; |
| 625 | { |
| 626 | return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JEQ, 0, v); |
| 627 | } |
| 628 | |
| 629 | static struct block * |
| 630 | gen_cmp_gt(offrel, offset, size, v) |
| 631 | enum e_offrel offrel; |
| 632 | u_int offset, size; |
| 633 | bpf_int32 v; |
| 634 | { |
| 635 | return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 0, v); |
| 636 | } |
| 637 | |
| 638 | static struct block * |
| 639 | gen_cmp_ge(offrel, offset, size, v) |
| 640 | enum e_offrel offrel; |
| 641 | u_int offset, size; |
| 642 | bpf_int32 v; |
| 643 | { |
| 644 | return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 0, v); |
| 645 | } |
| 646 | |
| 647 | static struct block * |
| 648 | gen_cmp_lt(offrel, offset, size, v) |
| 649 | enum e_offrel offrel; |
| 650 | u_int offset, size; |
| 651 | bpf_int32 v; |
| 652 | { |
| 653 | return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 1, v); |
| 654 | } |
| 655 | |
| 656 | static struct block * |
| 657 | gen_cmp_le(offrel, offset, size, v) |
| 658 | enum e_offrel offrel; |
| 659 | u_int offset, size; |
| 660 | bpf_int32 v; |
| 661 | { |
| 662 | return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 1, v); |
| 663 | } |
| 664 | |
| 665 | static struct block * |
| 666 | gen_mcmp(offrel, offset, size, v, mask) |
| 667 | enum e_offrel offrel; |
| 668 | u_int offset, size; |
| 669 | bpf_int32 v; |
| 670 | bpf_u_int32 mask; |
| 671 | { |
| 672 | return gen_ncmp(offrel, offset, size, mask, BPF_JEQ, 0, v); |
| 673 | } |
| 674 | |
| 675 | static struct block * |
| 676 | gen_bcmp(offrel, offset, size, v) |
| 677 | enum e_offrel offrel; |
| 678 | register u_int offset, size; |
| 679 | register const u_char *v; |
| 680 | { |
| 681 | register struct block *b, *tmp; |
| 682 | |
| 683 | b = NULL; |
| 684 | while (size >= 4) { |
| 685 | register const u_char *p = &v[size - 4]; |
| 686 | bpf_int32 w = ((bpf_int32)p[0] << 24) | |
| 687 | ((bpf_int32)p[1] << 16) | ((bpf_int32)p[2] << 8) | p[3]; |
| 688 | |
| 689 | tmp = gen_cmp(offrel, offset + size - 4, BPF_W, w); |
| 690 | if (b != NULL) |
| 691 | gen_and(b, tmp); |
| 692 | b = tmp; |
| 693 | size -= 4; |
| 694 | } |
| 695 | while (size >= 2) { |
| 696 | register const u_char *p = &v[size - 2]; |
| 697 | bpf_int32 w = ((bpf_int32)p[0] << 8) | p[1]; |
| 698 | |
| 699 | tmp = gen_cmp(offrel, offset + size - 2, BPF_H, w); |
| 700 | if (b != NULL) |
| 701 | gen_and(b, tmp); |
| 702 | b = tmp; |
| 703 | size -= 2; |
| 704 | } |
| 705 | if (size > 0) { |
| 706 | tmp = gen_cmp(offrel, offset, BPF_B, (bpf_int32)v[0]); |
| 707 | if (b != NULL) |
| 708 | gen_and(b, tmp); |
| 709 | b = tmp; |
| 710 | } |
| 711 | return b; |
| 712 | } |
| 713 | |
| 714 | /* |
| 715 | * AND the field of size "size" at offset "offset" relative to the header |
| 716 | * specified by "offrel" with "mask", and compare it with the value "v" |
| 717 | * with the test specified by "jtype"; if "reverse" is true, the test |
| 718 | * should test the opposite of "jtype". |
| 719 | */ |
| 720 | static struct block * |
| 721 | gen_ncmp(offrel, offset, size, mask, jtype, reverse, v) |
| 722 | enum e_offrel offrel; |
| 723 | bpf_int32 v; |
| 724 | bpf_u_int32 offset, size, mask, jtype; |
| 725 | int reverse; |
| 726 | { |
| 727 | struct slist *s, *s2; |
| 728 | struct block *b; |
| 729 | |
| 730 | s = gen_load_a(offrel, offset, size); |
| 731 | |
| 732 | if (mask != 0xffffffff) { |
| 733 | s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K); |
| 734 | s2->s.k = mask; |
| 735 | sappend(s, s2); |
| 736 | } |
| 737 | |
| 738 | b = new_block(JMP(jtype)); |
| 739 | b->stmts = s; |
| 740 | b->s.k = v; |
| 741 | if (reverse && (jtype == BPF_JGT || jtype == BPF_JGE)) |
| 742 | gen_not(b); |
| 743 | return b; |
| 744 | } |
| 745 | |
| 746 | /* |
| 747 | * Various code constructs need to know the layout of the data link |
| 748 | * layer. These variables give the necessary offsets from the beginning |
| 749 | * of the packet data. |
| 750 | */ |
| 751 | |
| 752 | /* |
| 753 | * This is the offset of the beginning of the link-layer header from |
| 754 | * the beginning of the raw packet data. |
| 755 | * |
| 756 | * It's usually 0, except for 802.11 with a fixed-length radio header. |
| 757 | * (For 802.11 with a variable-length radio header, we have to generate |
| 758 | * code to compute that offset; off_ll is 0 in that case.) |
| 759 | */ |
| 760 | static u_int off_ll; |
| 761 | |
| 762 | /* |
| 763 | * If there's a variable-length header preceding the link-layer header, |
| 764 | * "reg_off_ll" is the register number for a register containing the |
| 765 | * length of that header, and therefore the offset of the link-layer |
| 766 | * header from the beginning of the raw packet data. Otherwise, |
| 767 | * "reg_off_ll" is -1. |
| 768 | */ |
| 769 | static int reg_off_ll; |
| 770 | |
| 771 | /* |
| 772 | * This is the offset of the beginning of the MAC-layer header from |
| 773 | * the beginning of the link-layer header. |
| 774 | * It's usually 0, except for ATM LANE, where it's the offset, relative |
| 775 | * to the beginning of the raw packet data, of the Ethernet header, and |
| 776 | * for Ethernet with various additional information. |
| 777 | */ |
| 778 | static u_int off_mac; |
| 779 | |
| 780 | /* |
| 781 | * This is the offset of the beginning of the MAC-layer payload, |
| 782 | * from the beginning of the raw packet data. |
| 783 | * |
| 784 | * I.e., it's the sum of the length of the link-layer header (without, |
| 785 | * for example, any 802.2 LLC header, so it's the MAC-layer |
| 786 | * portion of that header), plus any prefix preceding the |
| 787 | * link-layer header. |
| 788 | */ |
| 789 | static u_int off_macpl; |
| 790 | |
| 791 | /* |
| 792 | * This is 1 if the offset of the beginning of the MAC-layer payload |
| 793 | * from the beginning of the link-layer header is variable-length. |
| 794 | */ |
| 795 | static int off_macpl_is_variable; |
| 796 | |
| 797 | /* |
| 798 | * If the link layer has variable_length headers, "reg_off_macpl" |
| 799 | * is the register number for a register containing the length of the |
| 800 | * link-layer header plus the length of any variable-length header |
| 801 | * preceding the link-layer header. Otherwise, "reg_off_macpl" |
| 802 | * is -1. |
| 803 | */ |
| 804 | static int reg_off_macpl; |
| 805 | |
| 806 | /* |
| 807 | * "off_linktype" is the offset to information in the link-layer header |
| 808 | * giving the packet type. This offset is relative to the beginning |
| 809 | * of the link-layer header (i.e., it doesn't include off_ll). |
| 810 | * |
| 811 | * For Ethernet, it's the offset of the Ethernet type field. |
| 812 | * |
| 813 | * For link-layer types that always use 802.2 headers, it's the |
| 814 | * offset of the LLC header. |
| 815 | * |
| 816 | * For PPP, it's the offset of the PPP type field. |
| 817 | * |
| 818 | * For Cisco HDLC, it's the offset of the CHDLC type field. |
| 819 | * |
| 820 | * For BSD loopback, it's the offset of the AF_ value. |
| 821 | * |
| 822 | * For Linux cooked sockets, it's the offset of the type field. |
| 823 | * |
| 824 | * It's set to -1 for no encapsulation, in which case, IP is assumed. |
| 825 | */ |
| 826 | static u_int off_linktype; |
| 827 | |
| 828 | /* |
| 829 | * TRUE if "pppoes" appeared in the filter; it causes link-layer type |
| 830 | * checks to check the PPP header, assumed to follow a LAN-style link- |
| 831 | * layer header and a PPPoE session header. |
| 832 | */ |
| 833 | static int is_pppoes = 0; |
| 834 | |
| 835 | /* |
| 836 | * TRUE if the link layer includes an ATM pseudo-header. |
| 837 | */ |
| 838 | static int is_atm = 0; |
| 839 | |
| 840 | /* |
| 841 | * TRUE if "lane" appeared in the filter; it causes us to generate |
| 842 | * code that assumes LANE rather than LLC-encapsulated traffic in SunATM. |
| 843 | */ |
| 844 | static int is_lane = 0; |
| 845 | |
| 846 | /* |
| 847 | * These are offsets for the ATM pseudo-header. |
| 848 | */ |
| 849 | static u_int off_vpi; |
| 850 | static u_int off_vci; |
| 851 | static u_int off_proto; |
| 852 | |
| 853 | /* |
| 854 | * These are offsets for the MTP2 fields. |
| 855 | */ |
| 856 | static u_int off_li; |
| 857 | |
| 858 | /* |
| 859 | * These are offsets for the MTP3 fields. |
| 860 | */ |
| 861 | static u_int off_sio; |
| 862 | static u_int off_opc; |
| 863 | static u_int off_dpc; |
| 864 | static u_int off_sls; |
| 865 | |
| 866 | /* |
| 867 | * This is the offset of the first byte after the ATM pseudo_header, |
| 868 | * or -1 if there is no ATM pseudo-header. |
| 869 | */ |
| 870 | static u_int off_payload; |
| 871 | |
| 872 | /* |
| 873 | * These are offsets to the beginning of the network-layer header. |
| 874 | * They are relative to the beginning of the MAC-layer payload (i.e., |
| 875 | * they don't include off_ll or off_macpl). |
| 876 | * |
| 877 | * If the link layer never uses 802.2 LLC: |
| 878 | * |
| 879 | * "off_nl" and "off_nl_nosnap" are the same. |
| 880 | * |
| 881 | * If the link layer always uses 802.2 LLC: |
| 882 | * |
| 883 | * "off_nl" is the offset if there's a SNAP header following |
| 884 | * the 802.2 header; |
| 885 | * |
| 886 | * "off_nl_nosnap" is the offset if there's no SNAP header. |
| 887 | * |
| 888 | * If the link layer is Ethernet: |
| 889 | * |
| 890 | * "off_nl" is the offset if the packet is an Ethernet II packet |
| 891 | * (we assume no 802.3+802.2+SNAP); |
| 892 | * |
| 893 | * "off_nl_nosnap" is the offset if the packet is an 802.3 packet |
| 894 | * with an 802.2 header following it. |
| 895 | */ |
| 896 | static u_int off_nl; |
| 897 | static u_int off_nl_nosnap; |
| 898 | |
| 899 | static int linktype; |
| 900 | |
| 901 | static void |
| 902 | init_linktype(p) |
| 903 | pcap_t *p; |
| 904 | { |
| 905 | linktype = pcap_datalink(p); |
| 906 | #ifdef PCAP_FDDIPAD |
| 907 | pcap_fddipad = p->fddipad; |
| 908 | #endif |
| 909 | |
| 910 | /* |
| 911 | * Assume it's not raw ATM with a pseudo-header, for now. |
| 912 | */ |
| 913 | off_mac = 0; |
| 914 | is_atm = 0; |
| 915 | is_lane = 0; |
| 916 | off_vpi = -1; |
| 917 | off_vci = -1; |
| 918 | off_proto = -1; |
| 919 | off_payload = -1; |
| 920 | |
| 921 | /* |
| 922 | * And that we're not doing PPPoE. |
| 923 | */ |
| 924 | is_pppoes = 0; |
| 925 | |
| 926 | /* |
| 927 | * And assume we're not doing SS7. |
| 928 | */ |
| 929 | off_li = -1; |
| 930 | off_sio = -1; |
| 931 | off_opc = -1; |
| 932 | off_dpc = -1; |
| 933 | off_sls = -1; |
| 934 | |
| 935 | /* |
| 936 | * Also assume it's not 802.11. |
| 937 | */ |
| 938 | off_ll = 0; |
| 939 | off_macpl = 0; |
| 940 | off_macpl_is_variable = 0; |
| 941 | |
| 942 | orig_linktype = -1; |
| 943 | orig_nl = -1; |
| 944 | label_stack_depth = 0; |
| 945 | |
| 946 | reg_off_ll = -1; |
| 947 | reg_off_macpl = -1; |
| 948 | |
| 949 | switch (linktype) { |
| 950 | |
| 951 | case DLT_ARCNET: |
| 952 | off_linktype = 2; |
| 953 | off_macpl = 6; |
| 954 | off_nl = 0; /* XXX in reality, variable! */ |
| 955 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 956 | return; |
| 957 | |
| 958 | case DLT_ARCNET_LINUX: |
| 959 | off_linktype = 4; |
| 960 | off_macpl = 8; |
| 961 | off_nl = 0; /* XXX in reality, variable! */ |
| 962 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 963 | return; |
| 964 | |
| 965 | case DLT_EN10MB: |
| 966 | off_linktype = 12; |
| 967 | off_macpl = 14; /* Ethernet header length */ |
| 968 | off_nl = 0; /* Ethernet II */ |
| 969 | off_nl_nosnap = 3; /* 802.3+802.2 */ |
| 970 | return; |
| 971 | |
| 972 | case DLT_SLIP: |
| 973 | /* |
| 974 | * SLIP doesn't have a link level type. The 16 byte |
| 975 | * header is hacked into our SLIP driver. |
| 976 | */ |
| 977 | off_linktype = -1; |
| 978 | off_macpl = 16; |
| 979 | off_nl = 0; |
| 980 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 981 | return; |
| 982 | |
| 983 | case DLT_SLIP_BSDOS: |
| 984 | /* XXX this may be the same as the DLT_PPP_BSDOS case */ |
| 985 | off_linktype = -1; |
| 986 | /* XXX end */ |
| 987 | off_macpl = 24; |
| 988 | off_nl = 0; |
| 989 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 990 | return; |
| 991 | |
| 992 | case DLT_NULL: |
| 993 | case DLT_LOOP: |
| 994 | off_linktype = 0; |
| 995 | off_macpl = 4; |
| 996 | off_nl = 0; |
| 997 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 998 | return; |
| 999 | |
| 1000 | case DLT_ENC: |
| 1001 | off_linktype = 0; |
| 1002 | off_macpl = 12; |
| 1003 | off_nl = 0; |
| 1004 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1005 | return; |
| 1006 | |
| 1007 | case DLT_PPP: |
| 1008 | case DLT_PPP_PPPD: |
| 1009 | case DLT_C_HDLC: /* BSD/OS Cisco HDLC */ |
| 1010 | case DLT_PPP_SERIAL: /* NetBSD sync/async serial PPP */ |
| 1011 | off_linktype = 2; |
| 1012 | off_macpl = 4; |
| 1013 | off_nl = 0; |
| 1014 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1015 | return; |
| 1016 | |
| 1017 | case DLT_PPP_ETHER: |
| 1018 | /* |
| 1019 | * This does no include the Ethernet header, and |
| 1020 | * only covers session state. |
| 1021 | */ |
| 1022 | off_linktype = 6; |
| 1023 | off_macpl = 8; |
| 1024 | off_nl = 0; |
| 1025 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1026 | return; |
| 1027 | |
| 1028 | case DLT_PPP_BSDOS: |
| 1029 | off_linktype = 5; |
| 1030 | off_macpl = 24; |
| 1031 | off_nl = 0; |
| 1032 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1033 | return; |
| 1034 | |
| 1035 | case DLT_FDDI: |
| 1036 | /* |
| 1037 | * FDDI doesn't really have a link-level type field. |
| 1038 | * We set "off_linktype" to the offset of the LLC header. |
| 1039 | * |
| 1040 | * To check for Ethernet types, we assume that SSAP = SNAP |
| 1041 | * is being used and pick out the encapsulated Ethernet type. |
| 1042 | * XXX - should we generate code to check for SNAP? |
| 1043 | */ |
| 1044 | off_linktype = 13; |
| 1045 | #ifdef PCAP_FDDIPAD |
| 1046 | off_linktype += pcap_fddipad; |
| 1047 | #endif |
| 1048 | off_macpl = 13; /* FDDI MAC header length */ |
| 1049 | #ifdef PCAP_FDDIPAD |
| 1050 | off_macpl += pcap_fddipad; |
| 1051 | #endif |
| 1052 | off_nl = 8; /* 802.2+SNAP */ |
| 1053 | off_nl_nosnap = 3; /* 802.2 */ |
| 1054 | return; |
| 1055 | |
| 1056 | case DLT_IEEE802: |
| 1057 | /* |
| 1058 | * Token Ring doesn't really have a link-level type field. |
| 1059 | * We set "off_linktype" to the offset of the LLC header. |
| 1060 | * |
| 1061 | * To check for Ethernet types, we assume that SSAP = SNAP |
| 1062 | * is being used and pick out the encapsulated Ethernet type. |
| 1063 | * XXX - should we generate code to check for SNAP? |
| 1064 | * |
| 1065 | * XXX - the header is actually variable-length. |
| 1066 | * Some various Linux patched versions gave 38 |
| 1067 | * as "off_linktype" and 40 as "off_nl"; however, |
| 1068 | * if a token ring packet has *no* routing |
| 1069 | * information, i.e. is not source-routed, the correct |
| 1070 | * values are 20 and 22, as they are in the vanilla code. |
| 1071 | * |
| 1072 | * A packet is source-routed iff the uppermost bit |
| 1073 | * of the first byte of the source address, at an |
| 1074 | * offset of 8, has the uppermost bit set. If the |
| 1075 | * packet is source-routed, the total number of bytes |
| 1076 | * of routing information is 2 plus bits 0x1F00 of |
| 1077 | * the 16-bit value at an offset of 14 (shifted right |
| 1078 | * 8 - figure out which byte that is). |
| 1079 | */ |
| 1080 | off_linktype = 14; |
| 1081 | off_macpl = 14; /* Token Ring MAC header length */ |
| 1082 | off_nl = 8; /* 802.2+SNAP */ |
| 1083 | off_nl_nosnap = 3; /* 802.2 */ |
| 1084 | return; |
| 1085 | |
| 1086 | case DLT_IEEE802_11: |
| 1087 | case DLT_PRISM_HEADER: |
| 1088 | case DLT_IEEE802_11_RADIO_AVS: |
| 1089 | case DLT_IEEE802_11_RADIO: |
| 1090 | /* |
| 1091 | * 802.11 doesn't really have a link-level type field. |
| 1092 | * We set "off_linktype" to the offset of the LLC header. |
| 1093 | * |
| 1094 | * To check for Ethernet types, we assume that SSAP = SNAP |
| 1095 | * is being used and pick out the encapsulated Ethernet type. |
| 1096 | * XXX - should we generate code to check for SNAP? |
| 1097 | * |
| 1098 | * We also handle variable-length radio headers here. |
| 1099 | * The Prism header is in theory variable-length, but in |
| 1100 | * practice it's always 144 bytes long. However, some |
| 1101 | * drivers on Linux use ARPHRD_IEEE80211_PRISM, but |
| 1102 | * sometimes or always supply an AVS header, so we |
| 1103 | * have to check whether the radio header is a Prism |
| 1104 | * header or an AVS header, so, in practice, it's |
| 1105 | * variable-length. |
| 1106 | */ |
| 1107 | off_linktype = 24; |
| 1108 | off_macpl = 0; /* link-layer header is variable-length */ |
| 1109 | off_macpl_is_variable = 1; |
| 1110 | off_nl = 8; /* 802.2+SNAP */ |
| 1111 | off_nl_nosnap = 3; /* 802.2 */ |
| 1112 | return; |
| 1113 | |
| 1114 | case DLT_PPI: |
| 1115 | /* |
| 1116 | * At the moment we treat PPI the same way that we treat |
| 1117 | * normal Radiotap encoded packets. The difference is in |
| 1118 | * the function that generates the code at the beginning |
| 1119 | * to compute the header length. Since this code generator |
| 1120 | * of PPI supports bare 802.11 encapsulation only (i.e. |
| 1121 | * the encapsulated DLT should be DLT_IEEE802_11) we |
| 1122 | * generate code to check for this too. |
| 1123 | */ |
| 1124 | off_linktype = 24; |
| 1125 | off_macpl = 0; /* link-layer header is variable-length */ |
| 1126 | off_macpl_is_variable = 1; |
| 1127 | off_nl = 8; /* 802.2+SNAP */ |
| 1128 | off_nl_nosnap = 3; /* 802.2 */ |
| 1129 | return; |
| 1130 | |
| 1131 | case DLT_ATM_RFC1483: |
| 1132 | case DLT_ATM_CLIP: /* Linux ATM defines this */ |
| 1133 | /* |
| 1134 | * assume routed, non-ISO PDUs |
| 1135 | * (i.e., LLC = 0xAA-AA-03, OUT = 0x00-00-00) |
| 1136 | * |
| 1137 | * XXX - what about ISO PDUs, e.g. CLNP, ISIS, ESIS, |
| 1138 | * or PPP with the PPP NLPID (e.g., PPPoA)? The |
| 1139 | * latter would presumably be treated the way PPPoE |
| 1140 | * should be, so you can do "pppoe and udp port 2049" |
| 1141 | * or "pppoa and tcp port 80" and have it check for |
| 1142 | * PPPo{A,E} and a PPP protocol of IP and.... |
| 1143 | */ |
| 1144 | off_linktype = 0; |
| 1145 | off_macpl = 0; /* packet begins with LLC header */ |
| 1146 | off_nl = 8; /* 802.2+SNAP */ |
| 1147 | off_nl_nosnap = 3; /* 802.2 */ |
| 1148 | return; |
| 1149 | |
| 1150 | case DLT_SUNATM: |
| 1151 | /* |
| 1152 | * Full Frontal ATM; you get AALn PDUs with an ATM |
| 1153 | * pseudo-header. |
| 1154 | */ |
| 1155 | is_atm = 1; |
| 1156 | off_vpi = SUNATM_VPI_POS; |
| 1157 | off_vci = SUNATM_VCI_POS; |
| 1158 | off_proto = PROTO_POS; |
| 1159 | off_mac = -1; /* assume LLC-encapsulated, so no MAC-layer header */ |
| 1160 | off_payload = SUNATM_PKT_BEGIN_POS; |
| 1161 | off_linktype = off_payload; |
| 1162 | off_macpl = off_payload; /* if LLC-encapsulated */ |
| 1163 | off_nl = 8; /* 802.2+SNAP */ |
| 1164 | off_nl_nosnap = 3; /* 802.2 */ |
| 1165 | return; |
| 1166 | |
| 1167 | case DLT_RAW: |
| 1168 | case DLT_IPV4: |
| 1169 | case DLT_IPV6: |
| 1170 | off_linktype = -1; |
| 1171 | off_macpl = 0; |
| 1172 | off_nl = 0; |
| 1173 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1174 | return; |
| 1175 | |
| 1176 | case DLT_LINUX_SLL: /* fake header for Linux cooked socket */ |
| 1177 | off_linktype = 14; |
| 1178 | off_macpl = 16; |
| 1179 | off_nl = 0; |
| 1180 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1181 | return; |
| 1182 | |
| 1183 | case DLT_LTALK: |
| 1184 | /* |
| 1185 | * LocalTalk does have a 1-byte type field in the LLAP header, |
| 1186 | * but really it just indicates whether there is a "short" or |
| 1187 | * "long" DDP packet following. |
| 1188 | */ |
| 1189 | off_linktype = -1; |
| 1190 | off_macpl = 0; |
| 1191 | off_nl = 0; |
| 1192 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1193 | return; |
| 1194 | |
| 1195 | case DLT_IP_OVER_FC: |
| 1196 | /* |
| 1197 | * RFC 2625 IP-over-Fibre-Channel doesn't really have a |
| 1198 | * link-level type field. We set "off_linktype" to the |
| 1199 | * offset of the LLC header. |
| 1200 | * |
| 1201 | * To check for Ethernet types, we assume that SSAP = SNAP |
| 1202 | * is being used and pick out the encapsulated Ethernet type. |
| 1203 | * XXX - should we generate code to check for SNAP? RFC |
| 1204 | * 2625 says SNAP should be used. |
| 1205 | */ |
| 1206 | off_linktype = 16; |
| 1207 | off_macpl = 16; |
| 1208 | off_nl = 8; /* 802.2+SNAP */ |
| 1209 | off_nl_nosnap = 3; /* 802.2 */ |
| 1210 | return; |
| 1211 | |
| 1212 | case DLT_FRELAY: |
| 1213 | /* |
| 1214 | * XXX - we should set this to handle SNAP-encapsulated |
| 1215 | * frames (NLPID of 0x80). |
| 1216 | */ |
| 1217 | off_linktype = -1; |
| 1218 | off_macpl = 0; |
| 1219 | off_nl = 0; |
| 1220 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1221 | return; |
| 1222 | |
| 1223 | /* |
| 1224 | * the only BPF-interesting FRF.16 frames are non-control frames; |
| 1225 | * Frame Relay has a variable length link-layer |
| 1226 | * so lets start with offset 4 for now and increments later on (FIXME); |
| 1227 | */ |
| 1228 | case DLT_MFR: |
| 1229 | off_linktype = -1; |
| 1230 | off_macpl = 0; |
| 1231 | off_nl = 4; |
| 1232 | off_nl_nosnap = 0; /* XXX - for now -> no 802.2 LLC */ |
| 1233 | return; |
| 1234 | |
| 1235 | case DLT_APPLE_IP_OVER_IEEE1394: |
| 1236 | off_linktype = 16; |
| 1237 | off_macpl = 18; |
| 1238 | off_nl = 0; |
| 1239 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1240 | return; |
| 1241 | |
| 1242 | case DLT_SYMANTEC_FIREWALL: |
| 1243 | off_linktype = 6; |
| 1244 | off_macpl = 44; |
| 1245 | off_nl = 0; /* Ethernet II */ |
| 1246 | off_nl_nosnap = 0; /* XXX - what does it do with 802.3 packets? */ |
| 1247 | return; |
| 1248 | |
| 1249 | #ifdef HAVE_NET_PFVAR_H |
| 1250 | case DLT_PFLOG: |
| 1251 | off_linktype = 0; |
| 1252 | off_macpl = PFLOG_HDRLEN; |
| 1253 | off_nl = 0; |
| 1254 | off_nl_nosnap = 0; /* no 802.2 LLC */ |
| 1255 | return; |
| 1256 | #endif |
| 1257 | |
| 1258 | case DLT_JUNIPER_MFR: |
| 1259 | case DLT_JUNIPER_MLFR: |
| 1260 | case DLT_JUNIPER_MLPPP: |
| 1261 | case DLT_JUNIPER_PPP: |
| 1262 | case DLT_JUNIPER_CHDLC: |
| 1263 | case DLT_JUNIPER_FRELAY: |
| 1264 | off_linktype = 4; |
| 1265 | off_macpl = 4; |
| 1266 | off_nl = 0; |
| 1267 | off_nl_nosnap = -1; /* no 802.2 LLC */ |
| 1268 | return; |
| 1269 | |
| 1270 | case DLT_JUNIPER_ATM1: |
| 1271 | off_linktype = 4; /* in reality variable between 4-8 */ |
| 1272 | off_macpl = 4; /* in reality variable between 4-8 */ |
| 1273 | off_nl = 0; |
| 1274 | off_nl_nosnap = 10; |
| 1275 | return; |
| 1276 | |
| 1277 | case DLT_JUNIPER_ATM2: |
| 1278 | off_linktype = 8; /* in reality variable between 8-12 */ |
| 1279 | off_macpl = 8; /* in reality variable between 8-12 */ |
| 1280 | off_nl = 0; |
| 1281 | off_nl_nosnap = 10; |
| 1282 | return; |
| 1283 | |
| 1284 | /* frames captured on a Juniper PPPoE service PIC |
| 1285 | * contain raw ethernet frames */ |
| 1286 | case DLT_JUNIPER_PPPOE: |
| 1287 | case DLT_JUNIPER_ETHER: |
| 1288 | off_macpl = 14; |
| 1289 | off_linktype = 16; |
| 1290 | off_nl = 18; /* Ethernet II */ |
| 1291 | off_nl_nosnap = 21; /* 802.3+802.2 */ |
| 1292 | return; |
| 1293 | |
| 1294 | case DLT_JUNIPER_PPPOE_ATM: |
| 1295 | off_linktype = 4; |
| 1296 | off_macpl = 6; |
| 1297 | off_nl = 0; |
| 1298 | off_nl_nosnap = -1; /* no 802.2 LLC */ |
| 1299 | return; |
| 1300 | |
| 1301 | case DLT_JUNIPER_GGSN: |
| 1302 | off_linktype = 6; |
| 1303 | off_macpl = 12; |
| 1304 | off_nl = 0; |
| 1305 | off_nl_nosnap = -1; /* no 802.2 LLC */ |
| 1306 | return; |
| 1307 | |
| 1308 | case DLT_JUNIPER_ES: |
| 1309 | off_linktype = 6; |
| 1310 | off_macpl = -1; /* not really a network layer but raw IP addresses */ |
| 1311 | off_nl = -1; /* not really a network layer but raw IP addresses */ |
| 1312 | off_nl_nosnap = -1; /* no 802.2 LLC */ |
| 1313 | return; |
| 1314 | |
| 1315 | case DLT_JUNIPER_MONITOR: |
| 1316 | off_linktype = 12; |
| 1317 | off_macpl = 12; |
| 1318 | off_nl = 0; /* raw IP/IP6 header */ |
| 1319 | off_nl_nosnap = -1; /* no 802.2 LLC */ |
| 1320 | return; |
| 1321 | |
| 1322 | case DLT_JUNIPER_SERVICES: |
| 1323 | off_linktype = 12; |
| 1324 | off_macpl = -1; /* L3 proto location dep. on cookie type */ |
| 1325 | off_nl = -1; /* L3 proto location dep. on cookie type */ |
| 1326 | off_nl_nosnap = -1; /* no 802.2 LLC */ |
| 1327 | return; |
| 1328 | |
| 1329 | case DLT_JUNIPER_VP: |
| 1330 | off_linktype = 18; |
| 1331 | off_macpl = -1; |
| 1332 | off_nl = -1; |
| 1333 | off_nl_nosnap = -1; |
| 1334 | return; |
| 1335 | |
| 1336 | case DLT_JUNIPER_ST: |
| 1337 | off_linktype = 18; |
| 1338 | off_macpl = -1; |
| 1339 | off_nl = -1; |
| 1340 | off_nl_nosnap = -1; |
| 1341 | return; |
| 1342 | |
| 1343 | case DLT_JUNIPER_ISM: |
| 1344 | off_linktype = 8; |
| 1345 | off_macpl = -1; |
| 1346 | off_nl = -1; |
| 1347 | off_nl_nosnap = -1; |
| 1348 | return; |
| 1349 | |
| 1350 | case DLT_JUNIPER_VS: |
| 1351 | case DLT_JUNIPER_SRX_E2E: |
| 1352 | case DLT_JUNIPER_FIBRECHANNEL: |
| 1353 | case DLT_JUNIPER_ATM_CEMIC: |
| 1354 | off_linktype = 8; |
| 1355 | off_macpl = -1; |
| 1356 | off_nl = -1; |
| 1357 | off_nl_nosnap = -1; |
| 1358 | return; |
| 1359 | |
| 1360 | case DLT_MTP2: |
| 1361 | off_li = 2; |
| 1362 | off_sio = 3; |
| 1363 | off_opc = 4; |
| 1364 | off_dpc = 4; |
| 1365 | off_sls = 7; |
| 1366 | off_linktype = -1; |
| 1367 | off_macpl = -1; |
| 1368 | off_nl = -1; |
| 1369 | off_nl_nosnap = -1; |
| 1370 | return; |
| 1371 | |
| 1372 | case DLT_MTP2_WITH_PHDR: |
| 1373 | off_li = 6; |
| 1374 | off_sio = 7; |
| 1375 | off_opc = 8; |
| 1376 | off_dpc = 8; |
| 1377 | off_sls = 11; |
| 1378 | off_linktype = -1; |
| 1379 | off_macpl = -1; |
| 1380 | off_nl = -1; |
| 1381 | off_nl_nosnap = -1; |
| 1382 | return; |
| 1383 | |
| 1384 | case DLT_ERF: |
| 1385 | off_li = 22; |
| 1386 | off_sio = 23; |
| 1387 | off_opc = 24; |
| 1388 | off_dpc = 24; |
| 1389 | off_sls = 27; |
| 1390 | off_linktype = -1; |
| 1391 | off_macpl = -1; |
| 1392 | off_nl = -1; |
| 1393 | off_nl_nosnap = -1; |
| 1394 | return; |
| 1395 | |
| 1396 | #ifdef DLT_PFSYNC |
| 1397 | case DLT_PFSYNC: |
| 1398 | off_linktype = -1; |
| 1399 | off_macpl = 4; |
| 1400 | off_nl = 0; |
| 1401 | off_nl_nosnap = 0; |
| 1402 | return; |
| 1403 | #endif |
| 1404 | |
| 1405 | case DLT_AX25_KISS: |
| 1406 | /* |
| 1407 | * Currently, only raw "link[N:M]" filtering is supported. |
| 1408 | */ |
| 1409 | off_linktype = -1; /* variable, min 15, max 71 steps of 7 */ |
| 1410 | off_macpl = -1; |
| 1411 | off_nl = -1; /* variable, min 16, max 71 steps of 7 */ |
| 1412 | off_nl_nosnap = -1; /* no 802.2 LLC */ |
| 1413 | off_mac = 1; /* step over the kiss length byte */ |
| 1414 | return; |
| 1415 | |
| 1416 | case DLT_IPNET: |
| 1417 | off_linktype = 1; |
| 1418 | off_macpl = 24; /* ipnet header length */ |
| 1419 | off_nl = 0; |
| 1420 | off_nl_nosnap = -1; |
| 1421 | return; |
| 1422 | |
| 1423 | case DLT_NETANALYZER: |
| 1424 | off_mac = 4; /* MAC header is past 4-byte pseudo-header */ |
| 1425 | off_linktype = 16; /* includes 4-byte pseudo-header */ |
| 1426 | off_macpl = 18; /* pseudo-header+Ethernet header length */ |
| 1427 | off_nl = 0; /* Ethernet II */ |
| 1428 | off_nl_nosnap = 3; /* 802.3+802.2 */ |
| 1429 | return; |
| 1430 | |
| 1431 | case DLT_NETANALYZER_TRANSPARENT: |
| 1432 | off_mac = 12; /* MAC header is past 4-byte pseudo-header, preamble, and SFD */ |
| 1433 | off_linktype = 24; /* includes 4-byte pseudo-header+preamble+SFD */ |
| 1434 | off_macpl = 26; /* pseudo-header+preamble+SFD+Ethernet header length */ |
| 1435 | off_nl = 0; /* Ethernet II */ |
| 1436 | off_nl_nosnap = 3; /* 802.3+802.2 */ |
| 1437 | return; |
| 1438 | |
| 1439 | default: |
| 1440 | /* |
| 1441 | * For values in the range in which we've assigned new |
| 1442 | * DLT_ values, only raw "link[N:M]" filtering is supported. |
| 1443 | */ |
| 1444 | if (linktype >= DLT_MATCHING_MIN && |
| 1445 | linktype <= DLT_MATCHING_MAX) { |
| 1446 | off_linktype = -1; |
| 1447 | off_macpl = -1; |
| 1448 | off_nl = -1; |
| 1449 | off_nl_nosnap = -1; |
| 1450 | return; |
| 1451 | } |
| 1452 | |
| 1453 | } |
| 1454 | bpf_error("unknown data link type %d", linktype); |
| 1455 | /* NOTREACHED */ |
| 1456 | } |
| 1457 | |
| 1458 | /* |
| 1459 | * Load a value relative to the beginning of the link-layer header. |
| 1460 | * The link-layer header doesn't necessarily begin at the beginning |
| 1461 | * of the packet data; there might be a variable-length prefix containing |
| 1462 | * radio information. |
| 1463 | */ |
| 1464 | static struct slist * |
| 1465 | gen_load_llrel(offset, size) |
| 1466 | u_int offset, size; |
| 1467 | { |
| 1468 | struct slist *s, *s2; |
| 1469 | |
| 1470 | s = gen_llprefixlen(); |
| 1471 | |
| 1472 | /* |
| 1473 | * If "s" is non-null, it has code to arrange that the X register |
| 1474 | * contains the length of the prefix preceding the link-layer |
| 1475 | * header. |
| 1476 | * |
| 1477 | * Otherwise, the length of the prefix preceding the link-layer |
| 1478 | * header is "off_ll". |
| 1479 | */ |
| 1480 | if (s != NULL) { |
| 1481 | /* |
| 1482 | * There's a variable-length prefix preceding the |
| 1483 | * link-layer header. "s" points to a list of statements |
| 1484 | * that put the length of that prefix into the X register. |
| 1485 | * do an indirect load, to use the X register as an offset. |
| 1486 | */ |
| 1487 | s2 = new_stmt(BPF_LD|BPF_IND|size); |
| 1488 | s2->s.k = offset; |
| 1489 | sappend(s, s2); |
| 1490 | } else { |
| 1491 | /* |
| 1492 | * There is no variable-length header preceding the |
| 1493 | * link-layer header; add in off_ll, which, if there's |
| 1494 | * a fixed-length header preceding the link-layer header, |
| 1495 | * is the length of that header. |
| 1496 | */ |
| 1497 | s = new_stmt(BPF_LD|BPF_ABS|size); |
| 1498 | s->s.k = offset + off_ll; |
| 1499 | } |
| 1500 | return s; |
| 1501 | } |
| 1502 | |
| 1503 | /* |
| 1504 | * Load a value relative to the beginning of the MAC-layer payload. |
| 1505 | */ |
| 1506 | static struct slist * |
| 1507 | gen_load_macplrel(offset, size) |
| 1508 | u_int offset, size; |
| 1509 | { |
| 1510 | struct slist *s, *s2; |
| 1511 | |
| 1512 | s = gen_off_macpl(); |
| 1513 | |
| 1514 | /* |
| 1515 | * If s is non-null, the offset of the MAC-layer payload is |
| 1516 | * variable, and s points to a list of instructions that |
| 1517 | * arrange that the X register contains that offset. |
| 1518 | * |
| 1519 | * Otherwise, the offset of the MAC-layer payload is constant, |
| 1520 | * and is in off_macpl. |
| 1521 | */ |
| 1522 | if (s != NULL) { |
| 1523 | /* |
| 1524 | * The offset of the MAC-layer payload is in the X |
| 1525 | * register. Do an indirect load, to use the X register |
| 1526 | * as an offset. |
| 1527 | */ |
| 1528 | s2 = new_stmt(BPF_LD|BPF_IND|size); |
| 1529 | s2->s.k = offset; |
| 1530 | sappend(s, s2); |
| 1531 | } else { |
| 1532 | /* |
| 1533 | * The offset of the MAC-layer payload is constant, |
| 1534 | * and is in off_macpl; load the value at that offset |
| 1535 | * plus the specified offset. |
| 1536 | */ |
| 1537 | s = new_stmt(BPF_LD|BPF_ABS|size); |
| 1538 | s->s.k = off_macpl + offset; |
| 1539 | } |
| 1540 | return s; |
| 1541 | } |
| 1542 | |
| 1543 | /* |
| 1544 | * Load a value relative to the beginning of the specified header. |
| 1545 | */ |
| 1546 | static struct slist * |
| 1547 | gen_load_a(offrel, offset, size) |
| 1548 | enum e_offrel offrel; |
| 1549 | u_int offset, size; |
| 1550 | { |
| 1551 | struct slist *s, *s2; |
| 1552 | |
| 1553 | switch (offrel) { |
| 1554 | |
| 1555 | case OR_PACKET: |
| 1556 | s = new_stmt(BPF_LD|BPF_ABS|size); |
| 1557 | s->s.k = offset; |
| 1558 | break; |
| 1559 | |
| 1560 | case OR_LINK: |
| 1561 | s = gen_load_llrel(offset, size); |
| 1562 | break; |
| 1563 | |
| 1564 | case OR_MACPL: |
| 1565 | s = gen_load_macplrel(offset, size); |
| 1566 | break; |
| 1567 | |
| 1568 | case OR_NET: |
| 1569 | s = gen_load_macplrel(off_nl + offset, size); |
| 1570 | break; |
| 1571 | |
| 1572 | case OR_NET_NOSNAP: |
| 1573 | s = gen_load_macplrel(off_nl_nosnap + offset, size); |
| 1574 | break; |
| 1575 | |
| 1576 | case OR_TRAN_IPV4: |
| 1577 | /* |
| 1578 | * Load the X register with the length of the IPv4 header |
| 1579 | * (plus the offset of the link-layer header, if it's |
| 1580 | * preceded by a variable-length header such as a radio |
| 1581 | * header), in bytes. |
| 1582 | */ |
| 1583 | s = gen_loadx_iphdrlen(); |
| 1584 | |
| 1585 | /* |
| 1586 | * Load the item at {offset of the MAC-layer payload} + |
| 1587 | * {offset, relative to the start of the MAC-layer |
| 1588 | * paylod, of the IPv4 header} + {length of the IPv4 header} + |
| 1589 | * {specified offset}. |
| 1590 | * |
| 1591 | * (If the offset of the MAC-layer payload is variable, |
| 1592 | * it's included in the value in the X register, and |
| 1593 | * off_macpl is 0.) |
| 1594 | */ |
| 1595 | s2 = new_stmt(BPF_LD|BPF_IND|size); |
| 1596 | s2->s.k = off_macpl + off_nl + offset; |
| 1597 | sappend(s, s2); |
| 1598 | break; |
| 1599 | |
| 1600 | case OR_TRAN_IPV6: |
| 1601 | s = gen_load_macplrel(off_nl + 40 + offset, size); |
| 1602 | break; |
| 1603 | |
| 1604 | default: |
| 1605 | abort(); |
| 1606 | return NULL; |
| 1607 | } |
| 1608 | return s; |
| 1609 | } |
| 1610 | |
| 1611 | /* |
| 1612 | * Generate code to load into the X register the sum of the length of |
| 1613 | * the IPv4 header and any variable-length header preceding the link-layer |
| 1614 | * header. |
| 1615 | */ |
| 1616 | static struct slist * |
| 1617 | gen_loadx_iphdrlen() |
| 1618 | { |
| 1619 | struct slist *s, *s2; |
| 1620 | |
| 1621 | s = gen_off_macpl(); |
| 1622 | if (s != NULL) { |
| 1623 | /* |
| 1624 | * There's a variable-length prefix preceding the |
| 1625 | * link-layer header, or the link-layer header is itself |
| 1626 | * variable-length. "s" points to a list of statements |
| 1627 | * that put the offset of the MAC-layer payload into |
| 1628 | * the X register. |
| 1629 | * |
| 1630 | * The 4*([k]&0xf) addressing mode can't be used, as we |
| 1631 | * don't have a constant offset, so we have to load the |
| 1632 | * value in question into the A register and add to it |
| 1633 | * the value from the X register. |
| 1634 | */ |
| 1635 | s2 = new_stmt(BPF_LD|BPF_IND|BPF_B); |
| 1636 | s2->s.k = off_nl; |
| 1637 | sappend(s, s2); |
| 1638 | s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K); |
| 1639 | s2->s.k = 0xf; |
| 1640 | sappend(s, s2); |
| 1641 | s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K); |
| 1642 | s2->s.k = 2; |
| 1643 | sappend(s, s2); |
| 1644 | |
| 1645 | /* |
| 1646 | * The A register now contains the length of the |
| 1647 | * IP header. We need to add to it the offset of |
| 1648 | * the MAC-layer payload, which is still in the X |
| 1649 | * register, and move the result into the X register. |
| 1650 | */ |
| 1651 | sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X)); |
| 1652 | sappend(s, new_stmt(BPF_MISC|BPF_TAX)); |
| 1653 | } else { |
| 1654 | /* |
| 1655 | * There is no variable-length header preceding the |
| 1656 | * link-layer header, and the link-layer header is |
| 1657 | * fixed-length; load the length of the IPv4 header, |
| 1658 | * which is at an offset of off_nl from the beginning |
| 1659 | * of the MAC-layer payload, and thus at an offset |
| 1660 | * of off_mac_pl + off_nl from the beginning of the |
| 1661 | * raw packet data. |
| 1662 | */ |
| 1663 | s = new_stmt(BPF_LDX|BPF_MSH|BPF_B); |
| 1664 | s->s.k = off_macpl + off_nl; |
| 1665 | } |
| 1666 | return s; |
| 1667 | } |
| 1668 | |
| 1669 | static struct block * |
| 1670 | gen_uncond(rsense) |
| 1671 | int rsense; |
| 1672 | { |
| 1673 | struct block *b; |
| 1674 | struct slist *s; |
| 1675 | |
| 1676 | s = new_stmt(BPF_LD|BPF_IMM); |
| 1677 | s->s.k = !rsense; |
| 1678 | b = new_block(JMP(BPF_JEQ)); |
| 1679 | b->stmts = s; |
| 1680 | |
| 1681 | return b; |
| 1682 | } |
| 1683 | |
| 1684 | static inline struct block * |
| 1685 | gen_true() |
| 1686 | { |
| 1687 | return gen_uncond(1); |
| 1688 | } |
| 1689 | |
| 1690 | static inline struct block * |
| 1691 | gen_false() |
| 1692 | { |
| 1693 | return gen_uncond(0); |
| 1694 | } |
| 1695 | |
| 1696 | /* |
| 1697 | * Byte-swap a 32-bit number. |
| 1698 | * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on |
| 1699 | * big-endian platforms.) |
| 1700 | */ |
| 1701 | #define SWAPLONG(y) \ |
| 1702 | ((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff)) |
| 1703 | |
| 1704 | /* |
| 1705 | * Generate code to match a particular packet type. |
| 1706 | * |
| 1707 | * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP |
| 1708 | * value, if <= ETHERMTU. We use that to determine whether to |
| 1709 | * match the type/length field or to check the type/length field for |
| 1710 | * a value <= ETHERMTU to see whether it's a type field and then do |
| 1711 | * the appropriate test. |
| 1712 | */ |
| 1713 | static struct block * |
| 1714 | gen_ether_linktype(proto) |
| 1715 | register int proto; |
| 1716 | { |
| 1717 | struct block *b0, *b1; |
| 1718 | |
| 1719 | switch (proto) { |
| 1720 | |
| 1721 | case LLCSAP_ISONS: |
| 1722 | case LLCSAP_IP: |
| 1723 | case LLCSAP_NETBEUI: |
| 1724 | /* |
| 1725 | * OSI protocols and NetBEUI always use 802.2 encapsulation, |
| 1726 | * so we check the DSAP and SSAP. |
| 1727 | * |
| 1728 | * LLCSAP_IP checks for IP-over-802.2, rather |
| 1729 | * than IP-over-Ethernet or IP-over-SNAP. |
| 1730 | * |
| 1731 | * XXX - should we check both the DSAP and the |
| 1732 | * SSAP, like this, or should we check just the |
| 1733 | * DSAP, as we do for other types <= ETHERMTU |
| 1734 | * (i.e., other SAP values)? |
| 1735 | */ |
| 1736 | b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU); |
| 1737 | gen_not(b0); |
| 1738 | b1 = gen_cmp(OR_MACPL, 0, BPF_H, (bpf_int32) |
| 1739 | ((proto << 8) | proto)); |
| 1740 | gen_and(b0, b1); |
| 1741 | return b1; |
| 1742 | |
| 1743 | case LLCSAP_IPX: |
| 1744 | /* |
| 1745 | * Check for; |
| 1746 | * |
| 1747 | * Ethernet_II frames, which are Ethernet |
| 1748 | * frames with a frame type of ETHERTYPE_IPX; |
| 1749 | * |
| 1750 | * Ethernet_802.3 frames, which are 802.3 |
| 1751 | * frames (i.e., the type/length field is |
| 1752 | * a length field, <= ETHERMTU, rather than |
| 1753 | * a type field) with the first two bytes |
| 1754 | * after the Ethernet/802.3 header being |
| 1755 | * 0xFFFF; |
| 1756 | * |
| 1757 | * Ethernet_802.2 frames, which are 802.3 |
| 1758 | * frames with an 802.2 LLC header and |
| 1759 | * with the IPX LSAP as the DSAP in the LLC |
| 1760 | * header; |
| 1761 | * |
| 1762 | * Ethernet_SNAP frames, which are 802.3 |
| 1763 | * frames with an LLC header and a SNAP |
| 1764 | * header and with an OUI of 0x000000 |
| 1765 | * (encapsulated Ethernet) and a protocol |
| 1766 | * ID of ETHERTYPE_IPX in the SNAP header. |
| 1767 | * |
| 1768 | * XXX - should we generate the same code both |
| 1769 | * for tests for LLCSAP_IPX and for ETHERTYPE_IPX? |
| 1770 | */ |
| 1771 | |
| 1772 | /* |
| 1773 | * This generates code to check both for the |
| 1774 | * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3. |
| 1775 | */ |
| 1776 | b0 = gen_cmp(OR_MACPL, 0, BPF_B, (bpf_int32)LLCSAP_IPX); |
| 1777 | b1 = gen_cmp(OR_MACPL, 0, BPF_H, (bpf_int32)0xFFFF); |
| 1778 | gen_or(b0, b1); |
| 1779 | |
| 1780 | /* |
| 1781 | * Now we add code to check for SNAP frames with |
| 1782 | * ETHERTYPE_IPX, i.e. Ethernet_SNAP. |
| 1783 | */ |
| 1784 | b0 = gen_snap(0x000000, ETHERTYPE_IPX); |
| 1785 | gen_or(b0, b1); |
| 1786 | |
| 1787 | /* |
| 1788 | * Now we generate code to check for 802.3 |
| 1789 | * frames in general. |
| 1790 | */ |
| 1791 | b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU); |
| 1792 | gen_not(b0); |
| 1793 | |
| 1794 | /* |
| 1795 | * Now add the check for 802.3 frames before the |
| 1796 | * check for Ethernet_802.2 and Ethernet_802.3, |
| 1797 | * as those checks should only be done on 802.3 |
| 1798 | * frames, not on Ethernet frames. |
| 1799 | */ |
| 1800 | gen_and(b0, b1); |
| 1801 | |
| 1802 | /* |
| 1803 | * Now add the check for Ethernet_II frames, and |
| 1804 | * do that before checking for the other frame |
| 1805 | * types. |
| 1806 | */ |
| 1807 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 1808 | (bpf_int32)ETHERTYPE_IPX); |
| 1809 | gen_or(b0, b1); |
| 1810 | return b1; |
| 1811 | |
| 1812 | case ETHERTYPE_ATALK: |
| 1813 | case ETHERTYPE_AARP: |
| 1814 | /* |
| 1815 | * EtherTalk (AppleTalk protocols on Ethernet link |
| 1816 | * layer) may use 802.2 encapsulation. |
| 1817 | */ |
| 1818 | |
| 1819 | /* |
| 1820 | * Check for 802.2 encapsulation (EtherTalk phase 2?); |
| 1821 | * we check for an Ethernet type field less than |
| 1822 | * 1500, which means it's an 802.3 length field. |
| 1823 | */ |
| 1824 | b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU); |
| 1825 | gen_not(b0); |
| 1826 | |
| 1827 | /* |
| 1828 | * 802.2-encapsulated ETHERTYPE_ATALK packets are |
| 1829 | * SNAP packets with an organization code of |
| 1830 | * 0x080007 (Apple, for Appletalk) and a protocol |
| 1831 | * type of ETHERTYPE_ATALK (Appletalk). |
| 1832 | * |
| 1833 | * 802.2-encapsulated ETHERTYPE_AARP packets are |
| 1834 | * SNAP packets with an organization code of |
| 1835 | * 0x000000 (encapsulated Ethernet) and a protocol |
| 1836 | * type of ETHERTYPE_AARP (Appletalk ARP). |
| 1837 | */ |
| 1838 | if (proto == ETHERTYPE_ATALK) |
| 1839 | b1 = gen_snap(0x080007, ETHERTYPE_ATALK); |
| 1840 | else /* proto == ETHERTYPE_AARP */ |
| 1841 | b1 = gen_snap(0x000000, ETHERTYPE_AARP); |
| 1842 | gen_and(b0, b1); |
| 1843 | |
| 1844 | /* |
| 1845 | * Check for Ethernet encapsulation (Ethertalk |
| 1846 | * phase 1?); we just check for the Ethernet |
| 1847 | * protocol type. |
| 1848 | */ |
| 1849 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto); |
| 1850 | |
| 1851 | gen_or(b0, b1); |
| 1852 | return b1; |
| 1853 | |
| 1854 | default: |
| 1855 | if (proto <= ETHERMTU) { |
| 1856 | /* |
| 1857 | * This is an LLC SAP value, so the frames |
| 1858 | * that match would be 802.2 frames. |
| 1859 | * Check that the frame is an 802.2 frame |
| 1860 | * (i.e., that the length/type field is |
| 1861 | * a length field, <= ETHERMTU) and |
| 1862 | * then check the DSAP. |
| 1863 | */ |
| 1864 | b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU); |
| 1865 | gen_not(b0); |
| 1866 | b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B, |
| 1867 | (bpf_int32)proto); |
| 1868 | gen_and(b0, b1); |
| 1869 | return b1; |
| 1870 | } else { |
| 1871 | /* |
| 1872 | * This is an Ethernet type, so compare |
| 1873 | * the length/type field with it (if |
| 1874 | * the frame is an 802.2 frame, the length |
| 1875 | * field will be <= ETHERMTU, and, as |
| 1876 | * "proto" is > ETHERMTU, this test |
| 1877 | * will fail and the frame won't match, |
| 1878 | * which is what we want). |
| 1879 | */ |
| 1880 | return gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 1881 | (bpf_int32)proto); |
| 1882 | } |
| 1883 | } |
| 1884 | } |
| 1885 | |
| 1886 | /* |
| 1887 | * "proto" is an Ethernet type value and for IPNET, if it is not IPv4 |
| 1888 | * or IPv6 then we have an error. |
| 1889 | */ |
| 1890 | static struct block * |
| 1891 | gen_ipnet_linktype(proto) |
| 1892 | register int proto; |
| 1893 | { |
| 1894 | switch (proto) { |
| 1895 | |
| 1896 | case ETHERTYPE_IP: |
| 1897 | return gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 1898 | (bpf_int32)IPH_AF_INET); |
| 1899 | /* NOTREACHED */ |
| 1900 | |
| 1901 | case ETHERTYPE_IPV6: |
| 1902 | return gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 1903 | (bpf_int32)IPH_AF_INET6); |
| 1904 | /* NOTREACHED */ |
| 1905 | |
| 1906 | default: |
| 1907 | break; |
| 1908 | } |
| 1909 | |
| 1910 | return gen_false(); |
| 1911 | } |
| 1912 | |
| 1913 | /* |
| 1914 | * Generate code to match a particular packet type. |
| 1915 | * |
| 1916 | * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP |
| 1917 | * value, if <= ETHERMTU. We use that to determine whether to |
| 1918 | * match the type field or to check the type field for the special |
| 1919 | * LINUX_SLL_P_802_2 value and then do the appropriate test. |
| 1920 | */ |
| 1921 | static struct block * |
| 1922 | gen_linux_sll_linktype(proto) |
| 1923 | register int proto; |
| 1924 | { |
| 1925 | struct block *b0, *b1; |
| 1926 | |
| 1927 | switch (proto) { |
| 1928 | |
| 1929 | case LLCSAP_ISONS: |
| 1930 | case LLCSAP_IP: |
| 1931 | case LLCSAP_NETBEUI: |
| 1932 | /* |
| 1933 | * OSI protocols and NetBEUI always use 802.2 encapsulation, |
| 1934 | * so we check the DSAP and SSAP. |
| 1935 | * |
| 1936 | * LLCSAP_IP checks for IP-over-802.2, rather |
| 1937 | * than IP-over-Ethernet or IP-over-SNAP. |
| 1938 | * |
| 1939 | * XXX - should we check both the DSAP and the |
| 1940 | * SSAP, like this, or should we check just the |
| 1941 | * DSAP, as we do for other types <= ETHERMTU |
| 1942 | * (i.e., other SAP values)? |
| 1943 | */ |
| 1944 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2); |
| 1945 | b1 = gen_cmp(OR_MACPL, 0, BPF_H, (bpf_int32) |
| 1946 | ((proto << 8) | proto)); |
| 1947 | gen_and(b0, b1); |
| 1948 | return b1; |
| 1949 | |
| 1950 | case LLCSAP_IPX: |
| 1951 | /* |
| 1952 | * Ethernet_II frames, which are Ethernet |
| 1953 | * frames with a frame type of ETHERTYPE_IPX; |
| 1954 | * |
| 1955 | * Ethernet_802.3 frames, which have a frame |
| 1956 | * type of LINUX_SLL_P_802_3; |
| 1957 | * |
| 1958 | * Ethernet_802.2 frames, which are 802.3 |
| 1959 | * frames with an 802.2 LLC header (i.e, have |
| 1960 | * a frame type of LINUX_SLL_P_802_2) and |
| 1961 | * with the IPX LSAP as the DSAP in the LLC |
| 1962 | * header; |
| 1963 | * |
| 1964 | * Ethernet_SNAP frames, which are 802.3 |
| 1965 | * frames with an LLC header and a SNAP |
| 1966 | * header and with an OUI of 0x000000 |
| 1967 | * (encapsulated Ethernet) and a protocol |
| 1968 | * ID of ETHERTYPE_IPX in the SNAP header. |
| 1969 | * |
| 1970 | * First, do the checks on LINUX_SLL_P_802_2 |
| 1971 | * frames; generate the check for either |
| 1972 | * Ethernet_802.2 or Ethernet_SNAP frames, and |
| 1973 | * then put a check for LINUX_SLL_P_802_2 frames |
| 1974 | * before it. |
| 1975 | */ |
| 1976 | b0 = gen_cmp(OR_MACPL, 0, BPF_B, (bpf_int32)LLCSAP_IPX); |
| 1977 | b1 = gen_snap(0x000000, ETHERTYPE_IPX); |
| 1978 | gen_or(b0, b1); |
| 1979 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2); |
| 1980 | gen_and(b0, b1); |
| 1981 | |
| 1982 | /* |
| 1983 | * Now check for 802.3 frames and OR that with |
| 1984 | * the previous test. |
| 1985 | */ |
| 1986 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_3); |
| 1987 | gen_or(b0, b1); |
| 1988 | |
| 1989 | /* |
| 1990 | * Now add the check for Ethernet_II frames, and |
| 1991 | * do that before checking for the other frame |
| 1992 | * types. |
| 1993 | */ |
| 1994 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 1995 | (bpf_int32)ETHERTYPE_IPX); |
| 1996 | gen_or(b0, b1); |
| 1997 | return b1; |
| 1998 | |
| 1999 | case ETHERTYPE_ATALK: |
| 2000 | case ETHERTYPE_AARP: |
| 2001 | /* |
| 2002 | * EtherTalk (AppleTalk protocols on Ethernet link |
| 2003 | * layer) may use 802.2 encapsulation. |
| 2004 | */ |
| 2005 | |
| 2006 | /* |
| 2007 | * Check for 802.2 encapsulation (EtherTalk phase 2?); |
| 2008 | * we check for the 802.2 protocol type in the |
| 2009 | * "Ethernet type" field. |
| 2010 | */ |
| 2011 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2); |
| 2012 | |
| 2013 | /* |
| 2014 | * 802.2-encapsulated ETHERTYPE_ATALK packets are |
| 2015 | * SNAP packets with an organization code of |
| 2016 | * 0x080007 (Apple, for Appletalk) and a protocol |
| 2017 | * type of ETHERTYPE_ATALK (Appletalk). |
| 2018 | * |
| 2019 | * 802.2-encapsulated ETHERTYPE_AARP packets are |
| 2020 | * SNAP packets with an organization code of |
| 2021 | * 0x000000 (encapsulated Ethernet) and a protocol |
| 2022 | * type of ETHERTYPE_AARP (Appletalk ARP). |
| 2023 | */ |
| 2024 | if (proto == ETHERTYPE_ATALK) |
| 2025 | b1 = gen_snap(0x080007, ETHERTYPE_ATALK); |
| 2026 | else /* proto == ETHERTYPE_AARP */ |
| 2027 | b1 = gen_snap(0x000000, ETHERTYPE_AARP); |
| 2028 | gen_and(b0, b1); |
| 2029 | |
| 2030 | /* |
| 2031 | * Check for Ethernet encapsulation (Ethertalk |
| 2032 | * phase 1?); we just check for the Ethernet |
| 2033 | * protocol type. |
| 2034 | */ |
| 2035 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto); |
| 2036 | |
| 2037 | gen_or(b0, b1); |
| 2038 | return b1; |
| 2039 | |
| 2040 | default: |
| 2041 | if (proto <= ETHERMTU) { |
| 2042 | /* |
| 2043 | * This is an LLC SAP value, so the frames |
| 2044 | * that match would be 802.2 frames. |
| 2045 | * Check for the 802.2 protocol type |
| 2046 | * in the "Ethernet type" field, and |
| 2047 | * then check the DSAP. |
| 2048 | */ |
| 2049 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 2050 | LINUX_SLL_P_802_2); |
| 2051 | b1 = gen_cmp(OR_LINK, off_macpl, BPF_B, |
| 2052 | (bpf_int32)proto); |
| 2053 | gen_and(b0, b1); |
| 2054 | return b1; |
| 2055 | } else { |
| 2056 | /* |
| 2057 | * This is an Ethernet type, so compare |
| 2058 | * the length/type field with it (if |
| 2059 | * the frame is an 802.2 frame, the length |
| 2060 | * field will be <= ETHERMTU, and, as |
| 2061 | * "proto" is > ETHERMTU, this test |
| 2062 | * will fail and the frame won't match, |
| 2063 | * which is what we want). |
| 2064 | */ |
| 2065 | return gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 2066 | (bpf_int32)proto); |
| 2067 | } |
| 2068 | } |
| 2069 | } |
| 2070 | |
| 2071 | static struct slist * |
| 2072 | gen_load_prism_llprefixlen() |
| 2073 | { |
| 2074 | struct slist *s1, *s2; |
| 2075 | struct slist *sjeq_avs_cookie; |
| 2076 | struct slist *sjcommon; |
| 2077 | |
| 2078 | /* |
| 2079 | * This code is not compatible with the optimizer, as |
| 2080 | * we are generating jmp instructions within a normal |
| 2081 | * slist of instructions |
| 2082 | */ |
| 2083 | no_optimize = 1; |
| 2084 | |
| 2085 | /* |
| 2086 | * Generate code to load the length of the radio header into |
| 2087 | * the register assigned to hold that length, if one has been |
| 2088 | * assigned. (If one hasn't been assigned, no code we've |
| 2089 | * generated uses that prefix, so we don't need to generate any |
| 2090 | * code to load it.) |
| 2091 | * |
| 2092 | * Some Linux drivers use ARPHRD_IEEE80211_PRISM but sometimes |
| 2093 | * or always use the AVS header rather than the Prism header. |
| 2094 | * We load a 4-byte big-endian value at the beginning of the |
| 2095 | * raw packet data, and see whether, when masked with 0xFFFFF000, |
| 2096 | * it's equal to 0x80211000. If so, that indicates that it's |
| 2097 | * an AVS header (the masked-out bits are the version number). |
| 2098 | * Otherwise, it's a Prism header. |
| 2099 | * |
| 2100 | * XXX - the Prism header is also, in theory, variable-length, |
| 2101 | * but no known software generates headers that aren't 144 |
| 2102 | * bytes long. |
| 2103 | */ |
| 2104 | if (reg_off_ll != -1) { |
| 2105 | /* |
| 2106 | * Load the cookie. |
| 2107 | */ |
| 2108 | s1 = new_stmt(BPF_LD|BPF_W|BPF_ABS); |
| 2109 | s1->s.k = 0; |
| 2110 | |
| 2111 | /* |
| 2112 | * AND it with 0xFFFFF000. |
| 2113 | */ |
| 2114 | s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K); |
| 2115 | s2->s.k = 0xFFFFF000; |
| 2116 | sappend(s1, s2); |
| 2117 | |
| 2118 | /* |
| 2119 | * Compare with 0x80211000. |
| 2120 | */ |
| 2121 | sjeq_avs_cookie = new_stmt(JMP(BPF_JEQ)); |
| 2122 | sjeq_avs_cookie->s.k = 0x80211000; |
| 2123 | sappend(s1, sjeq_avs_cookie); |
| 2124 | |
| 2125 | /* |
| 2126 | * If it's AVS: |
| 2127 | * |
| 2128 | * The 4 bytes at an offset of 4 from the beginning of |
| 2129 | * the AVS header are the length of the AVS header. |
| 2130 | * That field is big-endian. |
| 2131 | */ |
| 2132 | s2 = new_stmt(BPF_LD|BPF_W|BPF_ABS); |
| 2133 | s2->s.k = 4; |
| 2134 | sappend(s1, s2); |
| 2135 | sjeq_avs_cookie->s.jt = s2; |
| 2136 | |
| 2137 | /* |
| 2138 | * Now jump to the code to allocate a register |
| 2139 | * into which to save the header length and |
| 2140 | * store the length there. (The "jump always" |
| 2141 | * instruction needs to have the k field set; |
| 2142 | * it's added to the PC, so, as we're jumping |
| 2143 | * over a single instruction, it should be 1.) |
| 2144 | */ |
| 2145 | sjcommon = new_stmt(JMP(BPF_JA)); |
| 2146 | sjcommon->s.k = 1; |
| 2147 | sappend(s1, sjcommon); |
| 2148 | |
| 2149 | /* |
| 2150 | * Now for the code that handles the Prism header. |
| 2151 | * Just load the length of the Prism header (144) |
| 2152 | * into the A register. Have the test for an AVS |
| 2153 | * header branch here if we don't have an AVS header. |
| 2154 | */ |
| 2155 | s2 = new_stmt(BPF_LD|BPF_W|BPF_IMM); |
| 2156 | s2->s.k = 144; |
| 2157 | sappend(s1, s2); |
| 2158 | sjeq_avs_cookie->s.jf = s2; |
| 2159 | |
| 2160 | /* |
| 2161 | * Now allocate a register to hold that value and store |
| 2162 | * it. The code for the AVS header will jump here after |
| 2163 | * loading the length of the AVS header. |
| 2164 | */ |
| 2165 | s2 = new_stmt(BPF_ST); |
| 2166 | s2->s.k = reg_off_ll; |
| 2167 | sappend(s1, s2); |
| 2168 | sjcommon->s.jf = s2; |
| 2169 | |
| 2170 | /* |
| 2171 | * Now move it into the X register. |
| 2172 | */ |
| 2173 | s2 = new_stmt(BPF_MISC|BPF_TAX); |
| 2174 | sappend(s1, s2); |
| 2175 | |
| 2176 | return (s1); |
| 2177 | } else |
| 2178 | return (NULL); |
| 2179 | } |
| 2180 | |
| 2181 | static struct slist * |
| 2182 | gen_load_avs_llprefixlen() |
| 2183 | { |
| 2184 | struct slist *s1, *s2; |
| 2185 | |
| 2186 | /* |
| 2187 | * Generate code to load the length of the AVS header into |
| 2188 | * the register assigned to hold that length, if one has been |
| 2189 | * assigned. (If one hasn't been assigned, no code we've |
| 2190 | * generated uses that prefix, so we don't need to generate any |
| 2191 | * code to load it.) |
| 2192 | */ |
| 2193 | if (reg_off_ll != -1) { |
| 2194 | /* |
| 2195 | * The 4 bytes at an offset of 4 from the beginning of |
| 2196 | * the AVS header are the length of the AVS header. |
| 2197 | * That field is big-endian. |
| 2198 | */ |
| 2199 | s1 = new_stmt(BPF_LD|BPF_W|BPF_ABS); |
| 2200 | s1->s.k = 4; |
| 2201 | |
| 2202 | /* |
| 2203 | * Now allocate a register to hold that value and store |
| 2204 | * it. |
| 2205 | */ |
| 2206 | s2 = new_stmt(BPF_ST); |
| 2207 | s2->s.k = reg_off_ll; |
| 2208 | sappend(s1, s2); |
| 2209 | |
| 2210 | /* |
| 2211 | * Now move it into the X register. |
| 2212 | */ |
| 2213 | s2 = new_stmt(BPF_MISC|BPF_TAX); |
| 2214 | sappend(s1, s2); |
| 2215 | |
| 2216 | return (s1); |
| 2217 | } else |
| 2218 | return (NULL); |
| 2219 | } |
| 2220 | |
| 2221 | static struct slist * |
| 2222 | gen_load_radiotap_llprefixlen() |
| 2223 | { |
| 2224 | struct slist *s1, *s2; |
| 2225 | |
| 2226 | /* |
| 2227 | * Generate code to load the length of the radiotap header into |
| 2228 | * the register assigned to hold that length, if one has been |
| 2229 | * assigned. (If one hasn't been assigned, no code we've |
| 2230 | * generated uses that prefix, so we don't need to generate any |
| 2231 | * code to load it.) |
| 2232 | */ |
| 2233 | if (reg_off_ll != -1) { |
| 2234 | /* |
| 2235 | * The 2 bytes at offsets of 2 and 3 from the beginning |
| 2236 | * of the radiotap header are the length of the radiotap |
| 2237 | * header; unfortunately, it's little-endian, so we have |
| 2238 | * to load it a byte at a time and construct the value. |
| 2239 | */ |
| 2240 | |
| 2241 | /* |
| 2242 | * Load the high-order byte, at an offset of 3, shift it |
| 2243 | * left a byte, and put the result in the X register. |
| 2244 | */ |
| 2245 | s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS); |
| 2246 | s1->s.k = 3; |
| 2247 | s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K); |
| 2248 | sappend(s1, s2); |
| 2249 | s2->s.k = 8; |
| 2250 | s2 = new_stmt(BPF_MISC|BPF_TAX); |
| 2251 | sappend(s1, s2); |
| 2252 | |
| 2253 | /* |
| 2254 | * Load the next byte, at an offset of 2, and OR the |
| 2255 | * value from the X register into it. |
| 2256 | */ |
| 2257 | s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS); |
| 2258 | sappend(s1, s2); |
| 2259 | s2->s.k = 2; |
| 2260 | s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X); |
| 2261 | sappend(s1, s2); |
| 2262 | |
| 2263 | /* |
| 2264 | * Now allocate a register to hold that value and store |
| 2265 | * it. |
| 2266 | */ |
| 2267 | s2 = new_stmt(BPF_ST); |
| 2268 | s2->s.k = reg_off_ll; |
| 2269 | sappend(s1, s2); |
| 2270 | |
| 2271 | /* |
| 2272 | * Now move it into the X register. |
| 2273 | */ |
| 2274 | s2 = new_stmt(BPF_MISC|BPF_TAX); |
| 2275 | sappend(s1, s2); |
| 2276 | |
| 2277 | return (s1); |
| 2278 | } else |
| 2279 | return (NULL); |
| 2280 | } |
| 2281 | |
| 2282 | /* |
| 2283 | * At the moment we treat PPI as normal Radiotap encoded |
| 2284 | * packets. The difference is in the function that generates |
| 2285 | * the code at the beginning to compute the header length. |
| 2286 | * Since this code generator of PPI supports bare 802.11 |
| 2287 | * encapsulation only (i.e. the encapsulated DLT should be |
| 2288 | * DLT_IEEE802_11) we generate code to check for this too; |
| 2289 | * that's done in finish_parse(). |
| 2290 | */ |
| 2291 | static struct slist * |
| 2292 | gen_load_ppi_llprefixlen() |
| 2293 | { |
| 2294 | struct slist *s1, *s2; |
| 2295 | |
| 2296 | /* |
| 2297 | * Generate code to load the length of the radiotap header |
| 2298 | * into the register assigned to hold that length, if one has |
| 2299 | * been assigned. |
| 2300 | */ |
| 2301 | if (reg_off_ll != -1) { |
| 2302 | /* |
| 2303 | * The 2 bytes at offsets of 2 and 3 from the beginning |
| 2304 | * of the radiotap header are the length of the radiotap |
| 2305 | * header; unfortunately, it's little-endian, so we have |
| 2306 | * to load it a byte at a time and construct the value. |
| 2307 | */ |
| 2308 | |
| 2309 | /* |
| 2310 | * Load the high-order byte, at an offset of 3, shift it |
| 2311 | * left a byte, and put the result in the X register. |
| 2312 | */ |
| 2313 | s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS); |
| 2314 | s1->s.k = 3; |
| 2315 | s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K); |
| 2316 | sappend(s1, s2); |
| 2317 | s2->s.k = 8; |
| 2318 | s2 = new_stmt(BPF_MISC|BPF_TAX); |
| 2319 | sappend(s1, s2); |
| 2320 | |
| 2321 | /* |
| 2322 | * Load the next byte, at an offset of 2, and OR the |
| 2323 | * value from the X register into it. |
| 2324 | */ |
| 2325 | s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS); |
| 2326 | sappend(s1, s2); |
| 2327 | s2->s.k = 2; |
| 2328 | s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X); |
| 2329 | sappend(s1, s2); |
| 2330 | |
| 2331 | /* |
| 2332 | * Now allocate a register to hold that value and store |
| 2333 | * it. |
| 2334 | */ |
| 2335 | s2 = new_stmt(BPF_ST); |
| 2336 | s2->s.k = reg_off_ll; |
| 2337 | sappend(s1, s2); |
| 2338 | |
| 2339 | /* |
| 2340 | * Now move it into the X register. |
| 2341 | */ |
| 2342 | s2 = new_stmt(BPF_MISC|BPF_TAX); |
| 2343 | sappend(s1, s2); |
| 2344 | |
| 2345 | return (s1); |
| 2346 | } else |
| 2347 | return (NULL); |
| 2348 | } |
| 2349 | |
| 2350 | /* |
| 2351 | * Load a value relative to the beginning of the link-layer header after the 802.11 |
| 2352 | * header, i.e. LLC_SNAP. |
| 2353 | * The link-layer header doesn't necessarily begin at the beginning |
| 2354 | * of the packet data; there might be a variable-length prefix containing |
| 2355 | * radio information. |
| 2356 | */ |
| 2357 | static struct slist * |
| 2358 | gen_load_802_11_header_len(struct slist *s, struct slist *snext) |
| 2359 | { |
| 2360 | struct slist *s2; |
| 2361 | struct slist *sjset_data_frame_1; |
| 2362 | struct slist *sjset_data_frame_2; |
| 2363 | struct slist *sjset_qos; |
| 2364 | struct slist *sjset_radiotap_flags; |
| 2365 | struct slist *sjset_radiotap_tsft; |
| 2366 | struct slist *sjset_tsft_datapad, *sjset_notsft_datapad; |
| 2367 | struct slist *s_roundup; |
| 2368 | |
| 2369 | if (reg_off_macpl == -1) { |
| 2370 | /* |
| 2371 | * No register has been assigned to the offset of |
| 2372 | * the MAC-layer payload, which means nobody needs |
| 2373 | * it; don't bother computing it - just return |
| 2374 | * what we already have. |
| 2375 | */ |
| 2376 | return (s); |
| 2377 | } |
| 2378 | |
| 2379 | /* |
| 2380 | * This code is not compatible with the optimizer, as |
| 2381 | * we are generating jmp instructions within a normal |
| 2382 | * slist of instructions |
| 2383 | */ |
| 2384 | no_optimize = 1; |
| 2385 | |
| 2386 | /* |
| 2387 | * If "s" is non-null, it has code to arrange that the X register |
| 2388 | * contains the length of the prefix preceding the link-layer |
| 2389 | * header. |
| 2390 | * |
| 2391 | * Otherwise, the length of the prefix preceding the link-layer |
| 2392 | * header is "off_ll". |
| 2393 | */ |
| 2394 | if (s == NULL) { |
| 2395 | /* |
| 2396 | * There is no variable-length header preceding the |
| 2397 | * link-layer header. |
| 2398 | * |
| 2399 | * Load the length of the fixed-length prefix preceding |
| 2400 | * the link-layer header (if any) into the X register, |
| 2401 | * and store it in the reg_off_macpl register. |
| 2402 | * That length is off_ll. |
| 2403 | */ |
| 2404 | s = new_stmt(BPF_LDX|BPF_IMM); |
| 2405 | s->s.k = off_ll; |
| 2406 | } |
| 2407 | |
| 2408 | /* |
| 2409 | * The X register contains the offset of the beginning of the |
| 2410 | * link-layer header; add 24, which is the minimum length |
| 2411 | * of the MAC header for a data frame, to that, and store it |
| 2412 | * in reg_off_macpl, and then load the Frame Control field, |
| 2413 | * which is at the offset in the X register, with an indexed load. |
| 2414 | */ |
| 2415 | s2 = new_stmt(BPF_MISC|BPF_TXA); |
| 2416 | sappend(s, s2); |
| 2417 | s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_K); |
| 2418 | s2->s.k = 24; |
| 2419 | sappend(s, s2); |
| 2420 | s2 = new_stmt(BPF_ST); |
| 2421 | s2->s.k = reg_off_macpl; |
| 2422 | sappend(s, s2); |
| 2423 | |
| 2424 | s2 = new_stmt(BPF_LD|BPF_IND|BPF_B); |
| 2425 | s2->s.k = 0; |
| 2426 | sappend(s, s2); |
| 2427 | |
| 2428 | /* |
| 2429 | * Check the Frame Control field to see if this is a data frame; |
| 2430 | * a data frame has the 0x08 bit (b3) in that field set and the |
| 2431 | * 0x04 bit (b2) clear. |
| 2432 | */ |
| 2433 | sjset_data_frame_1 = new_stmt(JMP(BPF_JSET)); |
| 2434 | sjset_data_frame_1->s.k = 0x08; |
| 2435 | sappend(s, sjset_data_frame_1); |
| 2436 | |
| 2437 | /* |
| 2438 | * If b3 is set, test b2, otherwise go to the first statement of |
| 2439 | * the rest of the program. |
| 2440 | */ |
| 2441 | sjset_data_frame_1->s.jt = sjset_data_frame_2 = new_stmt(JMP(BPF_JSET)); |
| 2442 | sjset_data_frame_2->s.k = 0x04; |
| 2443 | sappend(s, sjset_data_frame_2); |
| 2444 | sjset_data_frame_1->s.jf = snext; |
| 2445 | |
| 2446 | /* |
| 2447 | * If b2 is not set, this is a data frame; test the QoS bit. |
| 2448 | * Otherwise, go to the first statement of the rest of the |
| 2449 | * program. |
| 2450 | */ |
| 2451 | sjset_data_frame_2->s.jt = snext; |
| 2452 | sjset_data_frame_2->s.jf = sjset_qos = new_stmt(JMP(BPF_JSET)); |
| 2453 | sjset_qos->s.k = 0x80; /* QoS bit */ |
| 2454 | sappend(s, sjset_qos); |
| 2455 | |
| 2456 | /* |
| 2457 | * If it's set, add 2 to reg_off_macpl, to skip the QoS |
| 2458 | * field. |
| 2459 | * Otherwise, go to the first statement of the rest of the |
| 2460 | * program. |
| 2461 | */ |
| 2462 | sjset_qos->s.jt = s2 = new_stmt(BPF_LD|BPF_MEM); |
| 2463 | s2->s.k = reg_off_macpl; |
| 2464 | sappend(s, s2); |
| 2465 | s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_IMM); |
| 2466 | s2->s.k = 2; |
| 2467 | sappend(s, s2); |
| 2468 | s2 = new_stmt(BPF_ST); |
| 2469 | s2->s.k = reg_off_macpl; |
| 2470 | sappend(s, s2); |
| 2471 | |
| 2472 | /* |
| 2473 | * If we have a radiotap header, look at it to see whether |
| 2474 | * there's Atheros padding between the MAC-layer header |
| 2475 | * and the payload. |
| 2476 | * |
| 2477 | * Note: all of the fields in the radiotap header are |
| 2478 | * little-endian, so we byte-swap all of the values |
| 2479 | * we test against, as they will be loaded as big-endian |
| 2480 | * values. |
| 2481 | */ |
| 2482 | if (linktype == DLT_IEEE802_11_RADIO) { |
| 2483 | /* |
| 2484 | * Is the IEEE80211_RADIOTAP_FLAGS bit (0x0000002) set |
| 2485 | * in the presence flag? |
| 2486 | */ |
| 2487 | sjset_qos->s.jf = s2 = new_stmt(BPF_LD|BPF_ABS|BPF_W); |
| 2488 | s2->s.k = 4; |
| 2489 | sappend(s, s2); |
| 2490 | |
| 2491 | sjset_radiotap_flags = new_stmt(JMP(BPF_JSET)); |
| 2492 | sjset_radiotap_flags->s.k = SWAPLONG(0x00000002); |
| 2493 | sappend(s, sjset_radiotap_flags); |
| 2494 | |
| 2495 | /* |
| 2496 | * If not, skip all of this. |
| 2497 | */ |
| 2498 | sjset_radiotap_flags->s.jf = snext; |
| 2499 | |
| 2500 | /* |
| 2501 | * Otherwise, is the IEEE80211_RADIOTAP_TSFT bit set? |
| 2502 | */ |
| 2503 | sjset_radiotap_tsft = sjset_radiotap_flags->s.jt = |
| 2504 | new_stmt(JMP(BPF_JSET)); |
| 2505 | sjset_radiotap_tsft->s.k = SWAPLONG(0x00000001); |
| 2506 | sappend(s, sjset_radiotap_tsft); |
| 2507 | |
| 2508 | /* |
| 2509 | * If IEEE80211_RADIOTAP_TSFT is set, the flags field is |
| 2510 | * at an offset of 16 from the beginning of the raw packet |
| 2511 | * data (8 bytes for the radiotap header and 8 bytes for |
| 2512 | * the TSFT field). |
| 2513 | * |
| 2514 | * Test whether the IEEE80211_RADIOTAP_F_DATAPAD bit (0x20) |
| 2515 | * is set. |
| 2516 | */ |
| 2517 | sjset_radiotap_tsft->s.jt = s2 = new_stmt(BPF_LD|BPF_ABS|BPF_B); |
| 2518 | s2->s.k = 16; |
| 2519 | sappend(s, s2); |
| 2520 | |
| 2521 | sjset_tsft_datapad = new_stmt(JMP(BPF_JSET)); |
| 2522 | sjset_tsft_datapad->s.k = 0x20; |
| 2523 | sappend(s, sjset_tsft_datapad); |
| 2524 | |
| 2525 | /* |
| 2526 | * If IEEE80211_RADIOTAP_TSFT is not set, the flags field is |
| 2527 | * at an offset of 8 from the beginning of the raw packet |
| 2528 | * data (8 bytes for the radiotap header). |
| 2529 | * |
| 2530 | * Test whether the IEEE80211_RADIOTAP_F_DATAPAD bit (0x20) |
| 2531 | * is set. |
| 2532 | */ |
| 2533 | sjset_radiotap_tsft->s.jf = s2 = new_stmt(BPF_LD|BPF_ABS|BPF_B); |
| 2534 | s2->s.k = 8; |
| 2535 | sappend(s, s2); |
| 2536 | |
| 2537 | sjset_notsft_datapad = new_stmt(JMP(BPF_JSET)); |
| 2538 | sjset_notsft_datapad->s.k = 0x20; |
| 2539 | sappend(s, sjset_notsft_datapad); |
| 2540 | |
| 2541 | /* |
| 2542 | * In either case, if IEEE80211_RADIOTAP_F_DATAPAD is |
| 2543 | * set, round the length of the 802.11 header to |
| 2544 | * a multiple of 4. Do that by adding 3 and then |
| 2545 | * dividing by and multiplying by 4, which we do by |
| 2546 | * ANDing with ~3. |
| 2547 | */ |
| 2548 | s_roundup = new_stmt(BPF_LD|BPF_MEM); |
| 2549 | s_roundup->s.k = reg_off_macpl; |
| 2550 | sappend(s, s_roundup); |
| 2551 | s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_IMM); |
| 2552 | s2->s.k = 3; |
| 2553 | sappend(s, s2); |
| 2554 | s2 = new_stmt(BPF_ALU|BPF_AND|BPF_IMM); |
| 2555 | s2->s.k = ~3; |
| 2556 | sappend(s, s2); |
| 2557 | s2 = new_stmt(BPF_ST); |
| 2558 | s2->s.k = reg_off_macpl; |
| 2559 | sappend(s, s2); |
| 2560 | |
| 2561 | sjset_tsft_datapad->s.jt = s_roundup; |
| 2562 | sjset_tsft_datapad->s.jf = snext; |
| 2563 | sjset_notsft_datapad->s.jt = s_roundup; |
| 2564 | sjset_notsft_datapad->s.jf = snext; |
| 2565 | } else |
| 2566 | sjset_qos->s.jf = snext; |
| 2567 | |
| 2568 | return s; |
| 2569 | } |
| 2570 | |
| 2571 | static void |
| 2572 | insert_compute_vloffsets(b) |
| 2573 | struct block *b; |
| 2574 | { |
| 2575 | struct slist *s; |
| 2576 | |
| 2577 | /* |
| 2578 | * For link-layer types that have a variable-length header |
| 2579 | * preceding the link-layer header, generate code to load |
| 2580 | * the offset of the link-layer header into the register |
| 2581 | * assigned to that offset, if any. |
| 2582 | */ |
| 2583 | switch (linktype) { |
| 2584 | |
| 2585 | case DLT_PRISM_HEADER: |
| 2586 | s = gen_load_prism_llprefixlen(); |
| 2587 | break; |
| 2588 | |
| 2589 | case DLT_IEEE802_11_RADIO_AVS: |
| 2590 | s = gen_load_avs_llprefixlen(); |
| 2591 | break; |
| 2592 | |
| 2593 | case DLT_IEEE802_11_RADIO: |
| 2594 | s = gen_load_radiotap_llprefixlen(); |
| 2595 | break; |
| 2596 | |
| 2597 | case DLT_PPI: |
| 2598 | s = gen_load_ppi_llprefixlen(); |
| 2599 | break; |
| 2600 | |
| 2601 | default: |
| 2602 | s = NULL; |
| 2603 | break; |
| 2604 | } |
| 2605 | |
| 2606 | /* |
| 2607 | * For link-layer types that have a variable-length link-layer |
| 2608 | * header, generate code to load the offset of the MAC-layer |
| 2609 | * payload into the register assigned to that offset, if any. |
| 2610 | */ |
| 2611 | switch (linktype) { |
| 2612 | |
| 2613 | case DLT_IEEE802_11: |
| 2614 | case DLT_PRISM_HEADER: |
| 2615 | case DLT_IEEE802_11_RADIO_AVS: |
| 2616 | case DLT_IEEE802_11_RADIO: |
| 2617 | case DLT_PPI: |
| 2618 | s = gen_load_802_11_header_len(s, b->stmts); |
| 2619 | break; |
| 2620 | } |
| 2621 | |
| 2622 | /* |
| 2623 | * If we have any offset-loading code, append all the |
| 2624 | * existing statements in the block to those statements, |
| 2625 | * and make the resulting list the list of statements |
| 2626 | * for the block. |
| 2627 | */ |
| 2628 | if (s != NULL) { |
| 2629 | sappend(s, b->stmts); |
| 2630 | b->stmts = s; |
| 2631 | } |
| 2632 | } |
| 2633 | |
| 2634 | static struct block * |
| 2635 | gen_ppi_dlt_check(void) |
| 2636 | { |
| 2637 | struct slist *s_load_dlt; |
| 2638 | struct block *b; |
| 2639 | |
| 2640 | if (linktype == DLT_PPI) |
| 2641 | { |
| 2642 | /* Create the statements that check for the DLT |
| 2643 | */ |
| 2644 | s_load_dlt = new_stmt(BPF_LD|BPF_W|BPF_ABS); |
| 2645 | s_load_dlt->s.k = 4; |
| 2646 | |
| 2647 | b = new_block(JMP(BPF_JEQ)); |
| 2648 | |
| 2649 | b->stmts = s_load_dlt; |
| 2650 | b->s.k = SWAPLONG(DLT_IEEE802_11); |
| 2651 | } |
| 2652 | else |
| 2653 | { |
| 2654 | b = NULL; |
| 2655 | } |
| 2656 | |
| 2657 | return b; |
| 2658 | } |
| 2659 | |
| 2660 | static struct slist * |
| 2661 | gen_prism_llprefixlen(void) |
| 2662 | { |
| 2663 | struct slist *s; |
| 2664 | |
| 2665 | if (reg_off_ll == -1) { |
| 2666 | /* |
| 2667 | * We haven't yet assigned a register for the length |
| 2668 | * of the radio header; allocate one. |
| 2669 | */ |
| 2670 | reg_off_ll = alloc_reg(); |
| 2671 | } |
| 2672 | |
| 2673 | /* |
| 2674 | * Load the register containing the radio length |
| 2675 | * into the X register. |
| 2676 | */ |
| 2677 | s = new_stmt(BPF_LDX|BPF_MEM); |
| 2678 | s->s.k = reg_off_ll; |
| 2679 | return s; |
| 2680 | } |
| 2681 | |
| 2682 | static struct slist * |
| 2683 | gen_avs_llprefixlen(void) |
| 2684 | { |
| 2685 | struct slist *s; |
| 2686 | |
| 2687 | if (reg_off_ll == -1) { |
| 2688 | /* |
| 2689 | * We haven't yet assigned a register for the length |
| 2690 | * of the AVS header; allocate one. |
| 2691 | */ |
| 2692 | reg_off_ll = alloc_reg(); |
| 2693 | } |
| 2694 | |
| 2695 | /* |
| 2696 | * Load the register containing the AVS length |
| 2697 | * into the X register. |
| 2698 | */ |
| 2699 | s = new_stmt(BPF_LDX|BPF_MEM); |
| 2700 | s->s.k = reg_off_ll; |
| 2701 | return s; |
| 2702 | } |
| 2703 | |
| 2704 | static struct slist * |
| 2705 | gen_radiotap_llprefixlen(void) |
| 2706 | { |
| 2707 | struct slist *s; |
| 2708 | |
| 2709 | if (reg_off_ll == -1) { |
| 2710 | /* |
| 2711 | * We haven't yet assigned a register for the length |
| 2712 | * of the radiotap header; allocate one. |
| 2713 | */ |
| 2714 | reg_off_ll = alloc_reg(); |
| 2715 | } |
| 2716 | |
| 2717 | /* |
| 2718 | * Load the register containing the radiotap length |
| 2719 | * into the X register. |
| 2720 | */ |
| 2721 | s = new_stmt(BPF_LDX|BPF_MEM); |
| 2722 | s->s.k = reg_off_ll; |
| 2723 | return s; |
| 2724 | } |
| 2725 | |
| 2726 | /* |
| 2727 | * At the moment we treat PPI as normal Radiotap encoded |
| 2728 | * packets. The difference is in the function that generates |
| 2729 | * the code at the beginning to compute the header length. |
| 2730 | * Since this code generator of PPI supports bare 802.11 |
| 2731 | * encapsulation only (i.e. the encapsulated DLT should be |
| 2732 | * DLT_IEEE802_11) we generate code to check for this too. |
| 2733 | */ |
| 2734 | static struct slist * |
| 2735 | gen_ppi_llprefixlen(void) |
| 2736 | { |
| 2737 | struct slist *s; |
| 2738 | |
| 2739 | if (reg_off_ll == -1) { |
| 2740 | /* |
| 2741 | * We haven't yet assigned a register for the length |
| 2742 | * of the radiotap header; allocate one. |
| 2743 | */ |
| 2744 | reg_off_ll = alloc_reg(); |
| 2745 | } |
| 2746 | |
| 2747 | /* |
| 2748 | * Load the register containing the PPI length |
| 2749 | * into the X register. |
| 2750 | */ |
| 2751 | s = new_stmt(BPF_LDX|BPF_MEM); |
| 2752 | s->s.k = reg_off_ll; |
| 2753 | return s; |
| 2754 | } |
| 2755 | |
| 2756 | /* |
| 2757 | * Generate code to compute the link-layer header length, if necessary, |
| 2758 | * putting it into the X register, and to return either a pointer to a |
| 2759 | * "struct slist" for the list of statements in that code, or NULL if |
| 2760 | * no code is necessary. |
| 2761 | */ |
| 2762 | static struct slist * |
| 2763 | gen_llprefixlen(void) |
| 2764 | { |
| 2765 | switch (linktype) { |
| 2766 | |
| 2767 | case DLT_PRISM_HEADER: |
| 2768 | return gen_prism_llprefixlen(); |
| 2769 | |
| 2770 | case DLT_IEEE802_11_RADIO_AVS: |
| 2771 | return gen_avs_llprefixlen(); |
| 2772 | |
| 2773 | case DLT_IEEE802_11_RADIO: |
| 2774 | return gen_radiotap_llprefixlen(); |
| 2775 | |
| 2776 | case DLT_PPI: |
| 2777 | return gen_ppi_llprefixlen(); |
| 2778 | |
| 2779 | default: |
| 2780 | return NULL; |
| 2781 | } |
| 2782 | } |
| 2783 | |
| 2784 | /* |
| 2785 | * Generate code to load the register containing the offset of the |
| 2786 | * MAC-layer payload into the X register; if no register for that offset |
| 2787 | * has been allocated, allocate it first. |
| 2788 | */ |
| 2789 | static struct slist * |
| 2790 | gen_off_macpl(void) |
| 2791 | { |
| 2792 | struct slist *s; |
| 2793 | |
| 2794 | if (off_macpl_is_variable) { |
| 2795 | if (reg_off_macpl == -1) { |
| 2796 | /* |
| 2797 | * We haven't yet assigned a register for the offset |
| 2798 | * of the MAC-layer payload; allocate one. |
| 2799 | */ |
| 2800 | reg_off_macpl = alloc_reg(); |
| 2801 | } |
| 2802 | |
| 2803 | /* |
| 2804 | * Load the register containing the offset of the MAC-layer |
| 2805 | * payload into the X register. |
| 2806 | */ |
| 2807 | s = new_stmt(BPF_LDX|BPF_MEM); |
| 2808 | s->s.k = reg_off_macpl; |
| 2809 | return s; |
| 2810 | } else { |
| 2811 | /* |
| 2812 | * That offset isn't variable, so we don't need to |
| 2813 | * generate any code. |
| 2814 | */ |
| 2815 | return NULL; |
| 2816 | } |
| 2817 | } |
| 2818 | |
| 2819 | /* |
| 2820 | * Map an Ethernet type to the equivalent PPP type. |
| 2821 | */ |
| 2822 | static int |
| 2823 | ethertype_to_ppptype(proto) |
| 2824 | int proto; |
| 2825 | { |
| 2826 | switch (proto) { |
| 2827 | |
| 2828 | case ETHERTYPE_IP: |
| 2829 | proto = PPP_IP; |
| 2830 | break; |
| 2831 | |
| 2832 | #ifdef INET6 |
| 2833 | case ETHERTYPE_IPV6: |
| 2834 | proto = PPP_IPV6; |
| 2835 | break; |
| 2836 | #endif |
| 2837 | |
| 2838 | case ETHERTYPE_DN: |
| 2839 | proto = PPP_DECNET; |
| 2840 | break; |
| 2841 | |
| 2842 | case ETHERTYPE_ATALK: |
| 2843 | proto = PPP_APPLE; |
| 2844 | break; |
| 2845 | |
| 2846 | case ETHERTYPE_NS: |
| 2847 | proto = PPP_NS; |
| 2848 | break; |
| 2849 | |
| 2850 | case LLCSAP_ISONS: |
| 2851 | proto = PPP_OSI; |
| 2852 | break; |
| 2853 | |
| 2854 | case LLCSAP_8021D: |
| 2855 | /* |
| 2856 | * I'm assuming the "Bridging PDU"s that go |
| 2857 | * over PPP are Spanning Tree Protocol |
| 2858 | * Bridging PDUs. |
| 2859 | */ |
| 2860 | proto = PPP_BRPDU; |
| 2861 | break; |
| 2862 | |
| 2863 | case LLCSAP_IPX: |
| 2864 | proto = PPP_IPX; |
| 2865 | break; |
| 2866 | } |
| 2867 | return (proto); |
| 2868 | } |
| 2869 | |
| 2870 | /* |
| 2871 | * Generate code to match a particular packet type by matching the |
| 2872 | * link-layer type field or fields in the 802.2 LLC header. |
| 2873 | * |
| 2874 | * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP |
| 2875 | * value, if <= ETHERMTU. |
| 2876 | */ |
| 2877 | static struct block * |
| 2878 | gen_linktype(proto) |
| 2879 | register int proto; |
| 2880 | { |
| 2881 | struct block *b0, *b1, *b2; |
| 2882 | |
| 2883 | /* are we checking MPLS-encapsulated packets? */ |
| 2884 | if (label_stack_depth > 0) { |
| 2885 | switch (proto) { |
| 2886 | case ETHERTYPE_IP: |
| 2887 | case PPP_IP: |
| 2888 | /* FIXME add other L3 proto IDs */ |
| 2889 | return gen_mpls_linktype(Q_IP); |
| 2890 | |
| 2891 | case ETHERTYPE_IPV6: |
| 2892 | case PPP_IPV6: |
| 2893 | /* FIXME add other L3 proto IDs */ |
| 2894 | return gen_mpls_linktype(Q_IPV6); |
| 2895 | |
| 2896 | default: |
| 2897 | bpf_error("unsupported protocol over mpls"); |
| 2898 | /* NOTREACHED */ |
| 2899 | } |
| 2900 | } |
| 2901 | |
| 2902 | /* |
| 2903 | * Are we testing PPPoE packets? |
| 2904 | */ |
| 2905 | if (is_pppoes) { |
| 2906 | /* |
| 2907 | * The PPPoE session header is part of the |
| 2908 | * MAC-layer payload, so all references |
| 2909 | * should be relative to the beginning of |
| 2910 | * that payload. |
| 2911 | */ |
| 2912 | |
| 2913 | /* |
| 2914 | * We use Ethernet protocol types inside libpcap; |
| 2915 | * map them to the corresponding PPP protocol types. |
| 2916 | */ |
| 2917 | proto = ethertype_to_ppptype(proto); |
| 2918 | return gen_cmp(OR_MACPL, off_linktype, BPF_H, (bpf_int32)proto); |
| 2919 | } |
| 2920 | |
| 2921 | switch (linktype) { |
| 2922 | |
| 2923 | case DLT_EN10MB: |
| 2924 | case DLT_NETANALYZER: |
| 2925 | case DLT_NETANALYZER_TRANSPARENT: |
| 2926 | return gen_ether_linktype(proto); |
| 2927 | /*NOTREACHED*/ |
| 2928 | break; |
| 2929 | |
| 2930 | case DLT_C_HDLC: |
| 2931 | switch (proto) { |
| 2932 | |
| 2933 | case LLCSAP_ISONS: |
| 2934 | proto = (proto << 8 | LLCSAP_ISONS); |
| 2935 | /* fall through */ |
| 2936 | |
| 2937 | default: |
| 2938 | return gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 2939 | (bpf_int32)proto); |
| 2940 | /*NOTREACHED*/ |
| 2941 | break; |
| 2942 | } |
| 2943 | break; |
| 2944 | |
| 2945 | case DLT_IEEE802_11: |
| 2946 | case DLT_PRISM_HEADER: |
| 2947 | case DLT_IEEE802_11_RADIO_AVS: |
| 2948 | case DLT_IEEE802_11_RADIO: |
| 2949 | case DLT_PPI: |
| 2950 | /* |
| 2951 | * Check that we have a data frame. |
| 2952 | */ |
| 2953 | b0 = gen_check_802_11_data_frame(); |
| 2954 | |
| 2955 | /* |
| 2956 | * Now check for the specified link-layer type. |
| 2957 | */ |
| 2958 | b1 = gen_llc_linktype(proto); |
| 2959 | gen_and(b0, b1); |
| 2960 | return b1; |
| 2961 | /*NOTREACHED*/ |
| 2962 | break; |
| 2963 | |
| 2964 | case DLT_FDDI: |
| 2965 | /* |
| 2966 | * XXX - check for asynchronous frames, as per RFC 1103. |
| 2967 | */ |
| 2968 | return gen_llc_linktype(proto); |
| 2969 | /*NOTREACHED*/ |
| 2970 | break; |
| 2971 | |
| 2972 | case DLT_IEEE802: |
| 2973 | /* |
| 2974 | * XXX - check for LLC PDUs, as per IEEE 802.5. |
| 2975 | */ |
| 2976 | return gen_llc_linktype(proto); |
| 2977 | /*NOTREACHED*/ |
| 2978 | break; |
| 2979 | |
| 2980 | case DLT_ATM_RFC1483: |
| 2981 | case DLT_ATM_CLIP: |
| 2982 | case DLT_IP_OVER_FC: |
| 2983 | return gen_llc_linktype(proto); |
| 2984 | /*NOTREACHED*/ |
| 2985 | break; |
| 2986 | |
| 2987 | case DLT_SUNATM: |
| 2988 | /* |
| 2989 | * If "is_lane" is set, check for a LANE-encapsulated |
| 2990 | * version of this protocol, otherwise check for an |
| 2991 | * LLC-encapsulated version of this protocol. |
| 2992 | * |
| 2993 | * We assume LANE means Ethernet, not Token Ring. |
| 2994 | */ |
| 2995 | if (is_lane) { |
| 2996 | /* |
| 2997 | * Check that the packet doesn't begin with an |
| 2998 | * LE Control marker. (We've already generated |
| 2999 | * a test for LANE.) |
| 3000 | */ |
| 3001 | b0 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H, |
| 3002 | 0xFF00); |
| 3003 | gen_not(b0); |
| 3004 | |
| 3005 | /* |
| 3006 | * Now generate an Ethernet test. |
| 3007 | */ |
| 3008 | b1 = gen_ether_linktype(proto); |
| 3009 | gen_and(b0, b1); |
| 3010 | return b1; |
| 3011 | } else { |
| 3012 | /* |
| 3013 | * Check for LLC encapsulation and then check the |
| 3014 | * protocol. |
| 3015 | */ |
| 3016 | b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0); |
| 3017 | b1 = gen_llc_linktype(proto); |
| 3018 | gen_and(b0, b1); |
| 3019 | return b1; |
| 3020 | } |
| 3021 | /*NOTREACHED*/ |
| 3022 | break; |
| 3023 | |
| 3024 | case DLT_LINUX_SLL: |
| 3025 | return gen_linux_sll_linktype(proto); |
| 3026 | /*NOTREACHED*/ |
| 3027 | break; |
| 3028 | |
| 3029 | case DLT_SLIP: |
| 3030 | case DLT_SLIP_BSDOS: |
| 3031 | case DLT_RAW: |
| 3032 | /* |
| 3033 | * These types don't provide any type field; packets |
| 3034 | * are always IPv4 or IPv6. |
| 3035 | * |
| 3036 | * XXX - for IPv4, check for a version number of 4, and, |
| 3037 | * for IPv6, check for a version number of 6? |
| 3038 | */ |
| 3039 | switch (proto) { |
| 3040 | |
| 3041 | case ETHERTYPE_IP: |
| 3042 | /* Check for a version number of 4. */ |
| 3043 | return gen_mcmp(OR_LINK, 0, BPF_B, 0x40, 0xF0); |
| 3044 | #ifdef INET6 |
| 3045 | case ETHERTYPE_IPV6: |
| 3046 | /* Check for a version number of 6. */ |
| 3047 | return gen_mcmp(OR_LINK, 0, BPF_B, 0x60, 0xF0); |
| 3048 | #endif |
| 3049 | |
| 3050 | default: |
| 3051 | return gen_false(); /* always false */ |
| 3052 | } |
| 3053 | /*NOTREACHED*/ |
| 3054 | break; |
| 3055 | |
| 3056 | case DLT_IPV4: |
| 3057 | /* |
| 3058 | * Raw IPv4, so no type field. |
| 3059 | */ |
| 3060 | if (proto == ETHERTYPE_IP) |
| 3061 | return gen_true(); /* always true */ |
| 3062 | |
| 3063 | /* Checking for something other than IPv4; always false */ |
| 3064 | return gen_false(); |
| 3065 | /*NOTREACHED*/ |
| 3066 | break; |
| 3067 | |
| 3068 | case DLT_IPV6: |
| 3069 | /* |
| 3070 | * Raw IPv6, so no type field. |
| 3071 | */ |
| 3072 | #ifdef INET6 |
| 3073 | if (proto == ETHERTYPE_IPV6) |
| 3074 | return gen_true(); /* always true */ |
| 3075 | #endif |
| 3076 | |
| 3077 | /* Checking for something other than IPv6; always false */ |
| 3078 | return gen_false(); |
| 3079 | /*NOTREACHED*/ |
| 3080 | break; |
| 3081 | |
| 3082 | case DLT_PPP: |
| 3083 | case DLT_PPP_PPPD: |
| 3084 | case DLT_PPP_SERIAL: |
| 3085 | case DLT_PPP_ETHER: |
| 3086 | /* |
| 3087 | * We use Ethernet protocol types inside libpcap; |
| 3088 | * map them to the corresponding PPP protocol types. |
| 3089 | */ |
| 3090 | proto = ethertype_to_ppptype(proto); |
| 3091 | return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto); |
| 3092 | /*NOTREACHED*/ |
| 3093 | break; |
| 3094 | |
| 3095 | case DLT_PPP_BSDOS: |
| 3096 | /* |
| 3097 | * We use Ethernet protocol types inside libpcap; |
| 3098 | * map them to the corresponding PPP protocol types. |
| 3099 | */ |
| 3100 | switch (proto) { |
| 3101 | |
| 3102 | case ETHERTYPE_IP: |
| 3103 | /* |
| 3104 | * Also check for Van Jacobson-compressed IP. |
| 3105 | * XXX - do this for other forms of PPP? |
| 3106 | */ |
| 3107 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_IP); |
| 3108 | b1 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJC); |
| 3109 | gen_or(b0, b1); |
| 3110 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJNC); |
| 3111 | gen_or(b1, b0); |
| 3112 | return b0; |
| 3113 | |
| 3114 | default: |
| 3115 | proto = ethertype_to_ppptype(proto); |
| 3116 | return gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 3117 | (bpf_int32)proto); |
| 3118 | } |
| 3119 | /*NOTREACHED*/ |
| 3120 | break; |
| 3121 | |
| 3122 | case DLT_NULL: |
| 3123 | case DLT_LOOP: |
| 3124 | case DLT_ENC: |
| 3125 | /* |
| 3126 | * For DLT_NULL, the link-layer header is a 32-bit |
| 3127 | * word containing an AF_ value in *host* byte order, |
| 3128 | * and for DLT_ENC, the link-layer header begins |
| 3129 | * with a 32-bit work containing an AF_ value in |
| 3130 | * host byte order. |
| 3131 | * |
| 3132 | * In addition, if we're reading a saved capture file, |
| 3133 | * the host byte order in the capture may not be the |
| 3134 | * same as the host byte order on this machine. |
| 3135 | * |
| 3136 | * For DLT_LOOP, the link-layer header is a 32-bit |
| 3137 | * word containing an AF_ value in *network* byte order. |
| 3138 | * |
| 3139 | * XXX - AF_ values may, unfortunately, be platform- |
| 3140 | * dependent; for example, FreeBSD's AF_INET6 is 24 |
| 3141 | * whilst NetBSD's and OpenBSD's is 26. |
| 3142 | * |
| 3143 | * This means that, when reading a capture file, just |
| 3144 | * checking for our AF_INET6 value won't work if the |
| 3145 | * capture file came from another OS. |
| 3146 | */ |
| 3147 | switch (proto) { |
| 3148 | |
| 3149 | case ETHERTYPE_IP: |
| 3150 | proto = AF_INET; |
| 3151 | break; |
| 3152 | |
| 3153 | #ifdef INET6 |
| 3154 | case ETHERTYPE_IPV6: |
| 3155 | proto = AF_INET6; |
| 3156 | break; |
| 3157 | #endif |
| 3158 | |
| 3159 | default: |
| 3160 | /* |
| 3161 | * Not a type on which we support filtering. |
| 3162 | * XXX - support those that have AF_ values |
| 3163 | * #defined on this platform, at least? |
| 3164 | */ |
| 3165 | return gen_false(); |
| 3166 | } |
| 3167 | |
| 3168 | if (linktype == DLT_NULL || linktype == DLT_ENC) { |
| 3169 | /* |
| 3170 | * The AF_ value is in host byte order, but |
| 3171 | * the BPF interpreter will convert it to |
| 3172 | * network byte order. |
| 3173 | * |
| 3174 | * If this is a save file, and it's from a |
| 3175 | * machine with the opposite byte order to |
| 3176 | * ours, we byte-swap the AF_ value. |
| 3177 | * |
| 3178 | * Then we run it through "htonl()", and |
| 3179 | * generate code to compare against the result. |
| 3180 | */ |
| 3181 | if (bpf_pcap->sf.rfile != NULL && |
| 3182 | bpf_pcap->sf.swapped) |
| 3183 | proto = SWAPLONG(proto); |
| 3184 | proto = htonl(proto); |
| 3185 | } |
| 3186 | return (gen_cmp(OR_LINK, 0, BPF_W, (bpf_int32)proto)); |
| 3187 | |
| 3188 | #ifdef HAVE_NET_PFVAR_H |
| 3189 | case DLT_PFLOG: |
| 3190 | /* |
| 3191 | * af field is host byte order in contrast to the rest of |
| 3192 | * the packet. |
| 3193 | */ |
| 3194 | if (proto == ETHERTYPE_IP) |
| 3195 | return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af), |
| 3196 | BPF_B, (bpf_int32)AF_INET)); |
| 3197 | #ifdef INET6 |
| 3198 | else if (proto == ETHERTYPE_IPV6) |
| 3199 | return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af), |
| 3200 | BPF_B, (bpf_int32)AF_INET6)); |
| 3201 | #endif /* INET6 */ |
| 3202 | else |
| 3203 | return gen_false(); |
| 3204 | /*NOTREACHED*/ |
| 3205 | break; |
| 3206 | #endif /* HAVE_NET_PFVAR_H */ |
| 3207 | |
| 3208 | case DLT_ARCNET: |
| 3209 | case DLT_ARCNET_LINUX: |
| 3210 | /* |
| 3211 | * XXX should we check for first fragment if the protocol |
| 3212 | * uses PHDS? |
| 3213 | */ |
| 3214 | switch (proto) { |
| 3215 | |
| 3216 | default: |
| 3217 | return gen_false(); |
| 3218 | |
| 3219 | #ifdef INET6 |
| 3220 | case ETHERTYPE_IPV6: |
| 3221 | return (gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 3222 | (bpf_int32)ARCTYPE_INET6)); |
| 3223 | #endif /* INET6 */ |
| 3224 | |
| 3225 | case ETHERTYPE_IP: |
| 3226 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 3227 | (bpf_int32)ARCTYPE_IP); |
| 3228 | b1 = gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 3229 | (bpf_int32)ARCTYPE_IP_OLD); |
| 3230 | gen_or(b0, b1); |
| 3231 | return (b1); |
| 3232 | |
| 3233 | case ETHERTYPE_ARP: |
| 3234 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 3235 | (bpf_int32)ARCTYPE_ARP); |
| 3236 | b1 = gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 3237 | (bpf_int32)ARCTYPE_ARP_OLD); |
| 3238 | gen_or(b0, b1); |
| 3239 | return (b1); |
| 3240 | |
| 3241 | case ETHERTYPE_REVARP: |
| 3242 | return (gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 3243 | (bpf_int32)ARCTYPE_REVARP)); |
| 3244 | |
| 3245 | case ETHERTYPE_ATALK: |
| 3246 | return (gen_cmp(OR_LINK, off_linktype, BPF_B, |
| 3247 | (bpf_int32)ARCTYPE_ATALK)); |
| 3248 | } |
| 3249 | /*NOTREACHED*/ |
| 3250 | break; |
| 3251 | |
| 3252 | case DLT_LTALK: |
| 3253 | switch (proto) { |
| 3254 | case ETHERTYPE_ATALK: |
| 3255 | return gen_true(); |
| 3256 | default: |
| 3257 | return gen_false(); |
| 3258 | } |
| 3259 | /*NOTREACHED*/ |
| 3260 | break; |
| 3261 | |
| 3262 | case DLT_FRELAY: |
| 3263 | /* |
| 3264 | * XXX - assumes a 2-byte Frame Relay header with |
| 3265 | * DLCI and flags. What if the address is longer? |
| 3266 | */ |
| 3267 | switch (proto) { |
| 3268 | |
| 3269 | case ETHERTYPE_IP: |
| 3270 | /* |
| 3271 | * Check for the special NLPID for IP. |
| 3272 | */ |
| 3273 | return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0xcc); |
| 3274 | |
| 3275 | #ifdef INET6 |
| 3276 | case ETHERTYPE_IPV6: |
| 3277 | /* |
| 3278 | * Check for the special NLPID for IPv6. |
| 3279 | */ |
| 3280 | return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0x8e); |
| 3281 | #endif |
| 3282 | |
| 3283 | case LLCSAP_ISONS: |
| 3284 | /* |
| 3285 | * Check for several OSI protocols. |
| 3286 | * |
| 3287 | * Frame Relay packets typically have an OSI |
| 3288 | * NLPID at the beginning; we check for each |
| 3289 | * of them. |
| 3290 | * |
| 3291 | * What we check for is the NLPID and a frame |
| 3292 | * control field of UI, i.e. 0x03 followed |
| 3293 | * by the NLPID. |
| 3294 | */ |
| 3295 | b0 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO8473_CLNP); |
| 3296 | b1 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO9542_ESIS); |
| 3297 | b2 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO10589_ISIS); |
| 3298 | gen_or(b1, b2); |
| 3299 | gen_or(b0, b2); |
| 3300 | return b2; |
| 3301 | |
| 3302 | default: |
| 3303 | return gen_false(); |
| 3304 | } |
| 3305 | /*NOTREACHED*/ |
| 3306 | break; |
| 3307 | |
| 3308 | case DLT_MFR: |
| 3309 | bpf_error("Multi-link Frame Relay link-layer type filtering not implemented"); |
| 3310 | |
| 3311 | case DLT_JUNIPER_MFR: |
| 3312 | case DLT_JUNIPER_MLFR: |
| 3313 | case DLT_JUNIPER_MLPPP: |
| 3314 | case DLT_JUNIPER_ATM1: |
| 3315 | case DLT_JUNIPER_ATM2: |
| 3316 | case DLT_JUNIPER_PPPOE: |
| 3317 | case DLT_JUNIPER_PPPOE_ATM: |
| 3318 | case DLT_JUNIPER_GGSN: |
| 3319 | case DLT_JUNIPER_ES: |
| 3320 | case DLT_JUNIPER_MONITOR: |
| 3321 | case DLT_JUNIPER_SERVICES: |
| 3322 | case DLT_JUNIPER_ETHER: |
| 3323 | case DLT_JUNIPER_PPP: |
| 3324 | case DLT_JUNIPER_FRELAY: |
| 3325 | case DLT_JUNIPER_CHDLC: |
| 3326 | case DLT_JUNIPER_VP: |
| 3327 | case DLT_JUNIPER_ST: |
| 3328 | case DLT_JUNIPER_ISM: |
| 3329 | case DLT_JUNIPER_VS: |
| 3330 | case DLT_JUNIPER_SRX_E2E: |
| 3331 | case DLT_JUNIPER_FIBRECHANNEL: |
| 3332 | case DLT_JUNIPER_ATM_CEMIC: |
| 3333 | |
| 3334 | /* just lets verify the magic number for now - |
| 3335 | * on ATM we may have up to 6 different encapsulations on the wire |
| 3336 | * and need a lot of heuristics to figure out that the payload |
| 3337 | * might be; |
| 3338 | * |
| 3339 | * FIXME encapsulation specific BPF_ filters |
| 3340 | */ |
| 3341 | return gen_mcmp(OR_LINK, 0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */ |
| 3342 | |
| 3343 | case DLT_IPNET: |
| 3344 | return gen_ipnet_linktype(proto); |
| 3345 | |
| 3346 | case DLT_LINUX_IRDA: |
| 3347 | bpf_error("IrDA link-layer type filtering not implemented"); |
| 3348 | |
| 3349 | case DLT_DOCSIS: |
| 3350 | bpf_error("DOCSIS link-layer type filtering not implemented"); |
| 3351 | |
| 3352 | case DLT_MTP2: |
| 3353 | case DLT_MTP2_WITH_PHDR: |
| 3354 | bpf_error("MTP2 link-layer type filtering not implemented"); |
| 3355 | |
| 3356 | case DLT_ERF: |
| 3357 | bpf_error("ERF link-layer type filtering not implemented"); |
| 3358 | |
| 3359 | #ifdef DLT_PFSYNC |
| 3360 | case DLT_PFSYNC: |
| 3361 | bpf_error("PFSYNC link-layer type filtering not implemented"); |
| 3362 | #endif |
| 3363 | |
| 3364 | case DLT_LINUX_LAPD: |
| 3365 | bpf_error("LAPD link-layer type filtering not implemented"); |
| 3366 | |
| 3367 | case DLT_USB: |
| 3368 | case DLT_USB_LINUX: |
| 3369 | case DLT_USB_LINUX_MMAPPED: |
| 3370 | bpf_error("USB link-layer type filtering not implemented"); |
| 3371 | |
| 3372 | case DLT_BLUETOOTH_HCI_H4: |
| 3373 | case DLT_BLUETOOTH_HCI_H4_WITH_PHDR: |
| 3374 | bpf_error("Bluetooth link-layer type filtering not implemented"); |
| 3375 | |
| 3376 | case DLT_CAN20B: |
| 3377 | case DLT_CAN_SOCKETCAN: |
| 3378 | bpf_error("CAN link-layer type filtering not implemented"); |
| 3379 | |
| 3380 | case DLT_IEEE802_15_4: |
| 3381 | case DLT_IEEE802_15_4_LINUX: |
| 3382 | case DLT_IEEE802_15_4_NONASK_PHY: |
| 3383 | case DLT_IEEE802_15_4_NOFCS: |
| 3384 | bpf_error("IEEE 802.15.4 link-layer type filtering not implemented"); |
| 3385 | |
| 3386 | case DLT_IEEE802_16_MAC_CPS_RADIO: |
| 3387 | bpf_error("IEEE 802.16 link-layer type filtering not implemented"); |
| 3388 | |
| 3389 | case DLT_SITA: |
| 3390 | bpf_error("SITA link-layer type filtering not implemented"); |
| 3391 | |
| 3392 | case DLT_RAIF1: |
| 3393 | bpf_error("RAIF1 link-layer type filtering not implemented"); |
| 3394 | |
| 3395 | case DLT_IPMB: |
| 3396 | bpf_error("IPMB link-layer type filtering not implemented"); |
| 3397 | |
| 3398 | case DLT_AX25_KISS: |
| 3399 | bpf_error("AX.25 link-layer type filtering not implemented"); |
| 3400 | } |
| 3401 | |
| 3402 | /* |
| 3403 | * All the types that have no encapsulation should either be |
| 3404 | * handled as DLT_SLIP, DLT_SLIP_BSDOS, and DLT_RAW are, if |
| 3405 | * all packets are IP packets, or should be handled in some |
| 3406 | * special case, if none of them are (if some are and some |
| 3407 | * aren't, the lack of encapsulation is a problem, as we'd |
| 3408 | * have to find some other way of determining the packet type). |
| 3409 | * |
| 3410 | * Therefore, if "off_linktype" is -1, there's an error. |
| 3411 | */ |
| 3412 | if (off_linktype == (u_int)-1) |
| 3413 | abort(); |
| 3414 | |
| 3415 | /* |
| 3416 | * Any type not handled above should always have an Ethernet |
| 3417 | * type at an offset of "off_linktype". |
| 3418 | */ |
| 3419 | return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto); |
| 3420 | } |
| 3421 | |
| 3422 | /* |
| 3423 | * Check for an LLC SNAP packet with a given organization code and |
| 3424 | * protocol type; we check the entire contents of the 802.2 LLC and |
| 3425 | * snap headers, checking for DSAP and SSAP of SNAP and a control |
| 3426 | * field of 0x03 in the LLC header, and for the specified organization |
| 3427 | * code and protocol type in the SNAP header. |
| 3428 | */ |
| 3429 | static struct block * |
| 3430 | gen_snap(orgcode, ptype) |
| 3431 | bpf_u_int32 orgcode; |
| 3432 | bpf_u_int32 ptype; |
| 3433 | { |
| 3434 | u_char snapblock[8]; |
| 3435 | |
| 3436 | snapblock[0] = LLCSAP_SNAP; /* DSAP = SNAP */ |
| 3437 | snapblock[1] = LLCSAP_SNAP; /* SSAP = SNAP */ |
| 3438 | snapblock[2] = 0x03; /* control = UI */ |
| 3439 | snapblock[3] = (orgcode >> 16); /* upper 8 bits of organization code */ |
| 3440 | snapblock[4] = (orgcode >> 8); /* middle 8 bits of organization code */ |
| 3441 | snapblock[5] = (orgcode >> 0); /* lower 8 bits of organization code */ |
| 3442 | snapblock[6] = (ptype >> 8); /* upper 8 bits of protocol type */ |
| 3443 | snapblock[7] = (ptype >> 0); /* lower 8 bits of protocol type */ |
| 3444 | return gen_bcmp(OR_MACPL, 0, 8, snapblock); |
| 3445 | } |
| 3446 | |
| 3447 | /* |
| 3448 | * Generate code to match a particular packet type, for link-layer types |
| 3449 | * using 802.2 LLC headers. |
| 3450 | * |
| 3451 | * This is *NOT* used for Ethernet; "gen_ether_linktype()" is used |
| 3452 | * for that - it handles the D/I/X Ethernet vs. 802.3+802.2 issues. |
| 3453 | * |
| 3454 | * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP |
| 3455 | * value, if <= ETHERMTU. We use that to determine whether to |
| 3456 | * match the DSAP or both DSAP and LSAP or to check the OUI and |
| 3457 | * protocol ID in a SNAP header. |
| 3458 | */ |
| 3459 | static struct block * |
| 3460 | gen_llc_linktype(proto) |
| 3461 | int proto; |
| 3462 | { |
| 3463 | /* |
| 3464 | * XXX - handle token-ring variable-length header. |
| 3465 | */ |
| 3466 | switch (proto) { |
| 3467 | |
| 3468 | case LLCSAP_IP: |
| 3469 | case LLCSAP_ISONS: |
| 3470 | case LLCSAP_NETBEUI: |
| 3471 | /* |
| 3472 | * XXX - should we check both the DSAP and the |
| 3473 | * SSAP, like this, or should we check just the |
| 3474 | * DSAP, as we do for other types <= ETHERMTU |
| 3475 | * (i.e., other SAP values)? |
| 3476 | */ |
| 3477 | return gen_cmp(OR_MACPL, 0, BPF_H, (bpf_u_int32) |
| 3478 | ((proto << 8) | proto)); |
| 3479 | |
| 3480 | case LLCSAP_IPX: |
| 3481 | /* |
| 3482 | * XXX - are there ever SNAP frames for IPX on |
| 3483 | * non-Ethernet 802.x networks? |
| 3484 | */ |
| 3485 | return gen_cmp(OR_MACPL, 0, BPF_B, |
| 3486 | (bpf_int32)LLCSAP_IPX); |
| 3487 | |
| 3488 | case ETHERTYPE_ATALK: |
| 3489 | /* |
| 3490 | * 802.2-encapsulated ETHERTYPE_ATALK packets are |
| 3491 | * SNAP packets with an organization code of |
| 3492 | * 0x080007 (Apple, for Appletalk) and a protocol |
| 3493 | * type of ETHERTYPE_ATALK (Appletalk). |
| 3494 | * |
| 3495 | * XXX - check for an organization code of |
| 3496 | * encapsulated Ethernet as well? |
| 3497 | */ |
| 3498 | return gen_snap(0x080007, ETHERTYPE_ATALK); |
| 3499 | |
| 3500 | default: |
| 3501 | /* |
| 3502 | * XXX - we don't have to check for IPX 802.3 |
| 3503 | * here, but should we check for the IPX Ethertype? |
| 3504 | */ |
| 3505 | if (proto <= ETHERMTU) { |
| 3506 | /* |
| 3507 | * This is an LLC SAP value, so check |
| 3508 | * the DSAP. |
| 3509 | */ |
| 3510 | return gen_cmp(OR_MACPL, 0, BPF_B, (bpf_int32)proto); |
| 3511 | } else { |
| 3512 | /* |
| 3513 | * This is an Ethernet type; we assume that it's |
| 3514 | * unlikely that it'll appear in the right place |
| 3515 | * at random, and therefore check only the |
| 3516 | * location that would hold the Ethernet type |
| 3517 | * in a SNAP frame with an organization code of |
| 3518 | * 0x000000 (encapsulated Ethernet). |
| 3519 | * |
| 3520 | * XXX - if we were to check for the SNAP DSAP and |
| 3521 | * LSAP, as per XXX, and were also to check for an |
| 3522 | * organization code of 0x000000 (encapsulated |
| 3523 | * Ethernet), we'd do |
| 3524 | * |
| 3525 | * return gen_snap(0x000000, proto); |
| 3526 | * |
| 3527 | * here; for now, we don't, as per the above. |
| 3528 | * I don't know whether it's worth the extra CPU |
| 3529 | * time to do the right check or not. |
| 3530 | */ |
| 3531 | return gen_cmp(OR_MACPL, 6, BPF_H, (bpf_int32)proto); |
| 3532 | } |
| 3533 | } |
| 3534 | } |
| 3535 | |
| 3536 | static struct block * |
| 3537 | gen_hostop(addr, mask, dir, proto, src_off, dst_off) |
| 3538 | bpf_u_int32 addr; |
| 3539 | bpf_u_int32 mask; |
| 3540 | int dir, proto; |
| 3541 | u_int src_off, dst_off; |
| 3542 | { |
| 3543 | struct block *b0, *b1; |
| 3544 | u_int offset; |
| 3545 | |
| 3546 | switch (dir) { |
| 3547 | |
| 3548 | case Q_SRC: |
| 3549 | offset = src_off; |
| 3550 | break; |
| 3551 | |
| 3552 | case Q_DST: |
| 3553 | offset = dst_off; |
| 3554 | break; |
| 3555 | |
| 3556 | case Q_AND: |
| 3557 | b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off); |
| 3558 | b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off); |
| 3559 | gen_and(b0, b1); |
| 3560 | return b1; |
| 3561 | |
| 3562 | case Q_OR: |
| 3563 | case Q_DEFAULT: |
| 3564 | b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off); |
| 3565 | b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off); |
| 3566 | gen_or(b0, b1); |
| 3567 | return b1; |
| 3568 | |
| 3569 | default: |
| 3570 | abort(); |
| 3571 | } |
| 3572 | b0 = gen_linktype(proto); |
| 3573 | b1 = gen_mcmp(OR_NET, offset, BPF_W, (bpf_int32)addr, mask); |
| 3574 | gen_and(b0, b1); |
| 3575 | return b1; |
| 3576 | } |
| 3577 | |
| 3578 | #ifdef INET6 |
| 3579 | static struct block * |
| 3580 | gen_hostop6(addr, mask, dir, proto, src_off, dst_off) |
| 3581 | struct in6_addr *addr; |
| 3582 | struct in6_addr *mask; |
| 3583 | int dir, proto; |
| 3584 | u_int src_off, dst_off; |
| 3585 | { |
| 3586 | struct block *b0, *b1; |
| 3587 | u_int offset; |
| 3588 | u_int32_t *a, *m; |
| 3589 | |
| 3590 | switch (dir) { |
| 3591 | |
| 3592 | case Q_SRC: |
| 3593 | offset = src_off; |
| 3594 | break; |
| 3595 | |
| 3596 | case Q_DST: |
| 3597 | offset = dst_off; |
| 3598 | break; |
| 3599 | |
| 3600 | case Q_AND: |
| 3601 | b0 = gen_hostop6(addr, mask, Q_SRC, proto, src_off, dst_off); |
| 3602 | b1 = gen_hostop6(addr, mask, Q_DST, proto, src_off, dst_off); |
| 3603 | gen_and(b0, b1); |
| 3604 | return b1; |
| 3605 | |
| 3606 | case Q_OR: |
| 3607 | case Q_DEFAULT: |
| 3608 | b0 = gen_hostop6(addr, mask, Q_SRC, proto, src_off, dst_off); |
| 3609 | b1 = gen_hostop6(addr, mask, Q_DST, proto, src_off, dst_off); |
| 3610 | gen_or(b0, b1); |
| 3611 | return b1; |
| 3612 | |
| 3613 | default: |
| 3614 | abort(); |
| 3615 | } |
| 3616 | /* this order is important */ |
| 3617 | a = (u_int32_t *)addr; |
| 3618 | m = (u_int32_t *)mask; |
| 3619 | b1 = gen_mcmp(OR_NET, offset + 12, BPF_W, ntohl(a[3]), ntohl(m[3])); |
| 3620 | b0 = gen_mcmp(OR_NET, offset + 8, BPF_W, ntohl(a[2]), ntohl(m[2])); |
| 3621 | gen_and(b0, b1); |
| 3622 | b0 = gen_mcmp(OR_NET, offset + 4, BPF_W, ntohl(a[1]), ntohl(m[1])); |
| 3623 | gen_and(b0, b1); |
| 3624 | b0 = gen_mcmp(OR_NET, offset + 0, BPF_W, ntohl(a[0]), ntohl(m[0])); |
| 3625 | gen_and(b0, b1); |
| 3626 | b0 = gen_linktype(proto); |
| 3627 | gen_and(b0, b1); |
| 3628 | return b1; |
| 3629 | } |
| 3630 | #endif /*INET6*/ |
| 3631 | |
| 3632 | static struct block * |
| 3633 | gen_ehostop(eaddr, dir) |
| 3634 | register const u_char *eaddr; |
| 3635 | register int dir; |
| 3636 | { |
| 3637 | register struct block *b0, *b1; |
| 3638 | |
| 3639 | switch (dir) { |
| 3640 | case Q_SRC: |
| 3641 | return gen_bcmp(OR_LINK, off_mac + 6, 6, eaddr); |
| 3642 | |
| 3643 | case Q_DST: |
| 3644 | return gen_bcmp(OR_LINK, off_mac + 0, 6, eaddr); |
| 3645 | |
| 3646 | case Q_AND: |
| 3647 | b0 = gen_ehostop(eaddr, Q_SRC); |
| 3648 | b1 = gen_ehostop(eaddr, Q_DST); |
| 3649 | gen_and(b0, b1); |
| 3650 | return b1; |
| 3651 | |
| 3652 | case Q_DEFAULT: |
| 3653 | case Q_OR: |
| 3654 | b0 = gen_ehostop(eaddr, Q_SRC); |
| 3655 | b1 = gen_ehostop(eaddr, Q_DST); |
| 3656 | gen_or(b0, b1); |
| 3657 | return b1; |
| 3658 | |
| 3659 | case Q_ADDR1: |
| 3660 | bpf_error("'addr1' is only supported on 802.11 with 802.11 headers"); |
| 3661 | break; |
| 3662 | |
| 3663 | case Q_ADDR2: |
| 3664 | bpf_error("'addr2' is only supported on 802.11 with 802.11 headers"); |
| 3665 | break; |
| 3666 | |
| 3667 | case Q_ADDR3: |
| 3668 | bpf_error("'addr3' is only supported on 802.11 with 802.11 headers"); |
| 3669 | break; |
| 3670 | |
| 3671 | case Q_ADDR4: |
| 3672 | bpf_error("'addr4' is only supported on 802.11 with 802.11 headers"); |
| 3673 | break; |
| 3674 | |
| 3675 | case Q_RA: |
| 3676 | bpf_error("'ra' is only supported on 802.11 with 802.11 headers"); |
| 3677 | break; |
| 3678 | |
| 3679 | case Q_TA: |
| 3680 | bpf_error("'ta' is only supported on 802.11 with 802.11 headers"); |
| 3681 | break; |
| 3682 | } |
| 3683 | abort(); |
| 3684 | /* NOTREACHED */ |
| 3685 | } |
| 3686 | |
| 3687 | /* |
| 3688 | * Like gen_ehostop, but for DLT_FDDI |
| 3689 | */ |
| 3690 | static struct block * |
| 3691 | gen_fhostop(eaddr, dir) |
| 3692 | register const u_char *eaddr; |
| 3693 | register int dir; |
| 3694 | { |
| 3695 | struct block *b0, *b1; |
| 3696 | |
| 3697 | switch (dir) { |
| 3698 | case Q_SRC: |
| 3699 | #ifdef PCAP_FDDIPAD |
| 3700 | return gen_bcmp(OR_LINK, 6 + 1 + pcap_fddipad, 6, eaddr); |
| 3701 | #else |
| 3702 | return gen_bcmp(OR_LINK, 6 + 1, 6, eaddr); |
| 3703 | #endif |
| 3704 | |
| 3705 | case Q_DST: |
| 3706 | #ifdef PCAP_FDDIPAD |
| 3707 | return gen_bcmp(OR_LINK, 0 + 1 + pcap_fddipad, 6, eaddr); |
| 3708 | #else |
| 3709 | return gen_bcmp(OR_LINK, 0 + 1, 6, eaddr); |
| 3710 | #endif |
| 3711 | |
| 3712 | case Q_AND: |
| 3713 | b0 = gen_fhostop(eaddr, Q_SRC); |
| 3714 | b1 = gen_fhostop(eaddr, Q_DST); |
| 3715 | gen_and(b0, b1); |
| 3716 | return b1; |
| 3717 | |
| 3718 | case Q_DEFAULT: |
| 3719 | case Q_OR: |
| 3720 | b0 = gen_fhostop(eaddr, Q_SRC); |
| 3721 | b1 = gen_fhostop(eaddr, Q_DST); |
| 3722 | gen_or(b0, b1); |
| 3723 | return b1; |
| 3724 | |
| 3725 | case Q_ADDR1: |
| 3726 | bpf_error("'addr1' is only supported on 802.11"); |
| 3727 | break; |
| 3728 | |
| 3729 | case Q_ADDR2: |
| 3730 | bpf_error("'addr2' is only supported on 802.11"); |
| 3731 | break; |
| 3732 | |
| 3733 | case Q_ADDR3: |
| 3734 | bpf_error("'addr3' is only supported on 802.11"); |
| 3735 | break; |
| 3736 | |
| 3737 | case Q_ADDR4: |
| 3738 | bpf_error("'addr4' is only supported on 802.11"); |
| 3739 | break; |
| 3740 | |
| 3741 | case Q_RA: |
| 3742 | bpf_error("'ra' is only supported on 802.11"); |
| 3743 | break; |
| 3744 | |
| 3745 | case Q_TA: |
| 3746 | bpf_error("'ta' is only supported on 802.11"); |
| 3747 | break; |
| 3748 | } |
| 3749 | abort(); |
| 3750 | /* NOTREACHED */ |
| 3751 | } |
| 3752 | |
| 3753 | /* |
| 3754 | * Like gen_ehostop, but for DLT_IEEE802 (Token Ring) |
| 3755 | */ |
| 3756 | static struct block * |
| 3757 | gen_thostop(eaddr, dir) |
| 3758 | register const u_char *eaddr; |
| 3759 | register int dir; |
| 3760 | { |
| 3761 | register struct block *b0, *b1; |
| 3762 | |
| 3763 | switch (dir) { |
| 3764 | case Q_SRC: |
| 3765 | return gen_bcmp(OR_LINK, 8, 6, eaddr); |
| 3766 | |
| 3767 | case Q_DST: |
| 3768 | return gen_bcmp(OR_LINK, 2, 6, eaddr); |
| 3769 | |
| 3770 | case Q_AND: |
| 3771 | b0 = gen_thostop(eaddr, Q_SRC); |
| 3772 | b1 = gen_thostop(eaddr, Q_DST); |
| 3773 | gen_and(b0, b1); |
| 3774 | return b1; |
| 3775 | |
| 3776 | case Q_DEFAULT: |
| 3777 | case Q_OR: |
| 3778 | b0 = gen_thostop(eaddr, Q_SRC); |
| 3779 | b1 = gen_thostop(eaddr, Q_DST); |
| 3780 | gen_or(b0, b1); |
| 3781 | return b1; |
| 3782 | |
| 3783 | case Q_ADDR1: |
| 3784 | bpf_error("'addr1' is only supported on 802.11"); |
| 3785 | break; |
| 3786 | |
| 3787 | case Q_ADDR2: |
| 3788 | bpf_error("'addr2' is only supported on 802.11"); |
| 3789 | break; |
| 3790 | |
| 3791 | case Q_ADDR3: |
| 3792 | bpf_error("'addr3' is only supported on 802.11"); |
| 3793 | break; |
| 3794 | |
| 3795 | case Q_ADDR4: |
| 3796 | bpf_error("'addr4' is only supported on 802.11"); |
| 3797 | break; |
| 3798 | |
| 3799 | case Q_RA: |
| 3800 | bpf_error("'ra' is only supported on 802.11"); |
| 3801 | break; |
| 3802 | |
| 3803 | case Q_TA: |
| 3804 | bpf_error("'ta' is only supported on 802.11"); |
| 3805 | break; |
| 3806 | } |
| 3807 | abort(); |
| 3808 | /* NOTREACHED */ |
| 3809 | } |
| 3810 | |
| 3811 | /* |
| 3812 | * Like gen_ehostop, but for DLT_IEEE802_11 (802.11 wireless LAN) and |
| 3813 | * various 802.11 + radio headers. |
| 3814 | */ |
| 3815 | static struct block * |
| 3816 | gen_wlanhostop(eaddr, dir) |
| 3817 | register const u_char *eaddr; |
| 3818 | register int dir; |
| 3819 | { |
| 3820 | register struct block *b0, *b1, *b2; |
| 3821 | register struct slist *s; |
| 3822 | |
| 3823 | #ifdef ENABLE_WLAN_FILTERING_PATCH |
| 3824 | /* |
| 3825 | * TODO GV 20070613 |
| 3826 | * We need to disable the optimizer because the optimizer is buggy |
| 3827 | * and wipes out some LD instructions generated by the below |
| 3828 | * code to validate the Frame Control bits |
| 3829 | */ |
| 3830 | no_optimize = 1; |
| 3831 | #endif /* ENABLE_WLAN_FILTERING_PATCH */ |
| 3832 | |
| 3833 | switch (dir) { |
| 3834 | case Q_SRC: |
| 3835 | /* |
| 3836 | * Oh, yuk. |
| 3837 | * |
| 3838 | * For control frames, there is no SA. |
| 3839 | * |
| 3840 | * For management frames, SA is at an |
| 3841 | * offset of 10 from the beginning of |
| 3842 | * the packet. |
| 3843 | * |
| 3844 | * For data frames, SA is at an offset |
| 3845 | * of 10 from the beginning of the packet |
| 3846 | * if From DS is clear, at an offset of |
| 3847 | * 16 from the beginning of the packet |
| 3848 | * if From DS is set and To DS is clear, |
| 3849 | * and an offset of 24 from the beginning |
| 3850 | * of the packet if From DS is set and To DS |
| 3851 | * is set. |
| 3852 | */ |
| 3853 | |
| 3854 | /* |
| 3855 | * Generate the tests to be done for data frames |
| 3856 | * with From DS set. |
| 3857 | * |
| 3858 | * First, check for To DS set, i.e. check "link[1] & 0x01". |
| 3859 | */ |
| 3860 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 3861 | b1 = new_block(JMP(BPF_JSET)); |
| 3862 | b1->s.k = 0x01; /* To DS */ |
| 3863 | b1->stmts = s; |
| 3864 | |
| 3865 | /* |
| 3866 | * If To DS is set, the SA is at 24. |
| 3867 | */ |
| 3868 | b0 = gen_bcmp(OR_LINK, 24, 6, eaddr); |
| 3869 | gen_and(b1, b0); |
| 3870 | |
| 3871 | /* |
| 3872 | * Now, check for To DS not set, i.e. check |
| 3873 | * "!(link[1] & 0x01)". |
| 3874 | */ |
| 3875 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 3876 | b2 = new_block(JMP(BPF_JSET)); |
| 3877 | b2->s.k = 0x01; /* To DS */ |
| 3878 | b2->stmts = s; |
| 3879 | gen_not(b2); |
| 3880 | |
| 3881 | /* |
| 3882 | * If To DS is not set, the SA is at 16. |
| 3883 | */ |
| 3884 | b1 = gen_bcmp(OR_LINK, 16, 6, eaddr); |
| 3885 | gen_and(b2, b1); |
| 3886 | |
| 3887 | /* |
| 3888 | * Now OR together the last two checks. That gives |
| 3889 | * the complete set of checks for data frames with |
| 3890 | * From DS set. |
| 3891 | */ |
| 3892 | gen_or(b1, b0); |
| 3893 | |
| 3894 | /* |
| 3895 | * Now check for From DS being set, and AND that with |
| 3896 | * the ORed-together checks. |
| 3897 | */ |
| 3898 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 3899 | b1 = new_block(JMP(BPF_JSET)); |
| 3900 | b1->s.k = 0x02; /* From DS */ |
| 3901 | b1->stmts = s; |
| 3902 | gen_and(b1, b0); |
| 3903 | |
| 3904 | /* |
| 3905 | * Now check for data frames with From DS not set. |
| 3906 | */ |
| 3907 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 3908 | b2 = new_block(JMP(BPF_JSET)); |
| 3909 | b2->s.k = 0x02; /* From DS */ |
| 3910 | b2->stmts = s; |
| 3911 | gen_not(b2); |
| 3912 | |
| 3913 | /* |
| 3914 | * If From DS isn't set, the SA is at 10. |
| 3915 | */ |
| 3916 | b1 = gen_bcmp(OR_LINK, 10, 6, eaddr); |
| 3917 | gen_and(b2, b1); |
| 3918 | |
| 3919 | /* |
| 3920 | * Now OR together the checks for data frames with |
| 3921 | * From DS not set and for data frames with From DS |
| 3922 | * set; that gives the checks done for data frames. |
| 3923 | */ |
| 3924 | gen_or(b1, b0); |
| 3925 | |
| 3926 | /* |
| 3927 | * Now check for a data frame. |
| 3928 | * I.e, check "link[0] & 0x08". |
| 3929 | */ |
| 3930 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 3931 | b1 = new_block(JMP(BPF_JSET)); |
| 3932 | b1->s.k = 0x08; |
| 3933 | b1->stmts = s; |
| 3934 | |
| 3935 | /* |
| 3936 | * AND that with the checks done for data frames. |
| 3937 | */ |
| 3938 | gen_and(b1, b0); |
| 3939 | |
| 3940 | /* |
| 3941 | * If the high-order bit of the type value is 0, this |
| 3942 | * is a management frame. |
| 3943 | * I.e, check "!(link[0] & 0x08)". |
| 3944 | */ |
| 3945 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 3946 | b2 = new_block(JMP(BPF_JSET)); |
| 3947 | b2->s.k = 0x08; |
| 3948 | b2->stmts = s; |
| 3949 | gen_not(b2); |
| 3950 | |
| 3951 | /* |
| 3952 | * For management frames, the SA is at 10. |
| 3953 | */ |
| 3954 | b1 = gen_bcmp(OR_LINK, 10, 6, eaddr); |
| 3955 | gen_and(b2, b1); |
| 3956 | |
| 3957 | /* |
| 3958 | * OR that with the checks done for data frames. |
| 3959 | * That gives the checks done for management and |
| 3960 | * data frames. |
| 3961 | */ |
| 3962 | gen_or(b1, b0); |
| 3963 | |
| 3964 | /* |
| 3965 | * If the low-order bit of the type value is 1, |
| 3966 | * this is either a control frame or a frame |
| 3967 | * with a reserved type, and thus not a |
| 3968 | * frame with an SA. |
| 3969 | * |
| 3970 | * I.e., check "!(link[0] & 0x04)". |
| 3971 | */ |
| 3972 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 3973 | b1 = new_block(JMP(BPF_JSET)); |
| 3974 | b1->s.k = 0x04; |
| 3975 | b1->stmts = s; |
| 3976 | gen_not(b1); |
| 3977 | |
| 3978 | /* |
| 3979 | * AND that with the checks for data and management |
| 3980 | * frames. |
| 3981 | */ |
| 3982 | gen_and(b1, b0); |
| 3983 | return b0; |
| 3984 | |
| 3985 | case Q_DST: |
| 3986 | /* |
| 3987 | * Oh, yuk. |
| 3988 | * |
| 3989 | * For control frames, there is no DA. |
| 3990 | * |
| 3991 | * For management frames, DA is at an |
| 3992 | * offset of 4 from the beginning of |
| 3993 | * the packet. |
| 3994 | * |
| 3995 | * For data frames, DA is at an offset |
| 3996 | * of 4 from the beginning of the packet |
| 3997 | * if To DS is clear and at an offset of |
| 3998 | * 16 from the beginning of the packet |
| 3999 | * if To DS is set. |
| 4000 | */ |
| 4001 | |
| 4002 | /* |
| 4003 | * Generate the tests to be done for data frames. |
| 4004 | * |
| 4005 | * First, check for To DS set, i.e. "link[1] & 0x01". |
| 4006 | */ |
| 4007 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 4008 | b1 = new_block(JMP(BPF_JSET)); |
| 4009 | b1->s.k = 0x01; /* To DS */ |
| 4010 | b1->stmts = s; |
| 4011 | |
| 4012 | /* |
| 4013 | * If To DS is set, the DA is at 16. |
| 4014 | */ |
| 4015 | b0 = gen_bcmp(OR_LINK, 16, 6, eaddr); |
| 4016 | gen_and(b1, b0); |
| 4017 | |
| 4018 | /* |
| 4019 | * Now, check for To DS not set, i.e. check |
| 4020 | * "!(link[1] & 0x01)". |
| 4021 | */ |
| 4022 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 4023 | b2 = new_block(JMP(BPF_JSET)); |
| 4024 | b2->s.k = 0x01; /* To DS */ |
| 4025 | b2->stmts = s; |
| 4026 | gen_not(b2); |
| 4027 | |
| 4028 | /* |
| 4029 | * If To DS is not set, the DA is at 4. |
| 4030 | */ |
| 4031 | b1 = gen_bcmp(OR_LINK, 4, 6, eaddr); |
| 4032 | gen_and(b2, b1); |
| 4033 | |
| 4034 | /* |
| 4035 | * Now OR together the last two checks. That gives |
| 4036 | * the complete set of checks for data frames. |
| 4037 | */ |
| 4038 | gen_or(b1, b0); |
| 4039 | |
| 4040 | /* |
| 4041 | * Now check for a data frame. |
| 4042 | * I.e, check "link[0] & 0x08". |
| 4043 | */ |
| 4044 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 4045 | b1 = new_block(JMP(BPF_JSET)); |
| 4046 | b1->s.k = 0x08; |
| 4047 | b1->stmts = s; |
| 4048 | |
| 4049 | /* |
| 4050 | * AND that with the checks done for data frames. |
| 4051 | */ |
| 4052 | gen_and(b1, b0); |
| 4053 | |
| 4054 | /* |
| 4055 | * If the high-order bit of the type value is 0, this |
| 4056 | * is a management frame. |
| 4057 | * I.e, check "!(link[0] & 0x08)". |
| 4058 | */ |
| 4059 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 4060 | b2 = new_block(JMP(BPF_JSET)); |
| 4061 | b2->s.k = 0x08; |
| 4062 | b2->stmts = s; |
| 4063 | gen_not(b2); |
| 4064 | |
| 4065 | /* |
| 4066 | * For management frames, the DA is at 4. |
| 4067 | */ |
| 4068 | b1 = gen_bcmp(OR_LINK, 4, 6, eaddr); |
| 4069 | gen_and(b2, b1); |
| 4070 | |
| 4071 | /* |
| 4072 | * OR that with the checks done for data frames. |
| 4073 | * That gives the checks done for management and |
| 4074 | * data frames. |
| 4075 | */ |
| 4076 | gen_or(b1, b0); |
| 4077 | |
| 4078 | /* |
| 4079 | * If the low-order bit of the type value is 1, |
| 4080 | * this is either a control frame or a frame |
| 4081 | * with a reserved type, and thus not a |
| 4082 | * frame with an SA. |
| 4083 | * |
| 4084 | * I.e., check "!(link[0] & 0x04)". |
| 4085 | */ |
| 4086 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 4087 | b1 = new_block(JMP(BPF_JSET)); |
| 4088 | b1->s.k = 0x04; |
| 4089 | b1->stmts = s; |
| 4090 | gen_not(b1); |
| 4091 | |
| 4092 | /* |
| 4093 | * AND that with the checks for data and management |
| 4094 | * frames. |
| 4095 | */ |
| 4096 | gen_and(b1, b0); |
| 4097 | return b0; |
| 4098 | |
| 4099 | case Q_RA: |
| 4100 | /* |
| 4101 | * Not present in management frames; addr1 in other |
| 4102 | * frames. |
| 4103 | */ |
| 4104 | |
| 4105 | /* |
| 4106 | * If the high-order bit of the type value is 0, this |
| 4107 | * is a management frame. |
| 4108 | * I.e, check "(link[0] & 0x08)". |
| 4109 | */ |
| 4110 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 4111 | b1 = new_block(JMP(BPF_JSET)); |
| 4112 | b1->s.k = 0x08; |
| 4113 | b1->stmts = s; |
| 4114 | |
| 4115 | /* |
| 4116 | * Check addr1. |
| 4117 | */ |
| 4118 | b0 = gen_bcmp(OR_LINK, 4, 6, eaddr); |
| 4119 | |
| 4120 | /* |
| 4121 | * AND that with the check of addr1. |
| 4122 | */ |
| 4123 | gen_and(b1, b0); |
| 4124 | return (b0); |
| 4125 | |
| 4126 | case Q_TA: |
| 4127 | /* |
| 4128 | * Not present in management frames; addr2, if present, |
| 4129 | * in other frames. |
| 4130 | */ |
| 4131 | |
| 4132 | /* |
| 4133 | * Not present in CTS or ACK control frames. |
| 4134 | */ |
| 4135 | b0 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_TYPE_CTL, |
| 4136 | IEEE80211_FC0_TYPE_MASK); |
| 4137 | gen_not(b0); |
| 4138 | b1 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS, |
| 4139 | IEEE80211_FC0_SUBTYPE_MASK); |
| 4140 | gen_not(b1); |
| 4141 | b2 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK, |
| 4142 | IEEE80211_FC0_SUBTYPE_MASK); |
| 4143 | gen_not(b2); |
| 4144 | gen_and(b1, b2); |
| 4145 | gen_or(b0, b2); |
| 4146 | |
| 4147 | /* |
| 4148 | * If the high-order bit of the type value is 0, this |
| 4149 | * is a management frame. |
| 4150 | * I.e, check "(link[0] & 0x08)". |
| 4151 | */ |
| 4152 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 4153 | b1 = new_block(JMP(BPF_JSET)); |
| 4154 | b1->s.k = 0x08; |
| 4155 | b1->stmts = s; |
| 4156 | |
| 4157 | /* |
| 4158 | * AND that with the check for frames other than |
| 4159 | * CTS and ACK frames. |
| 4160 | */ |
| 4161 | gen_and(b1, b2); |
| 4162 | |
| 4163 | /* |
| 4164 | * Check addr2. |
| 4165 | */ |
| 4166 | b1 = gen_bcmp(OR_LINK, 10, 6, eaddr); |
| 4167 | gen_and(b2, b1); |
| 4168 | return b1; |
| 4169 | |
| 4170 | /* |
| 4171 | * XXX - add BSSID keyword? |
| 4172 | */ |
| 4173 | case Q_ADDR1: |
| 4174 | return (gen_bcmp(OR_LINK, 4, 6, eaddr)); |
| 4175 | |
| 4176 | case Q_ADDR2: |
| 4177 | /* |
| 4178 | * Not present in CTS or ACK control frames. |
| 4179 | */ |
| 4180 | b0 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_TYPE_CTL, |
| 4181 | IEEE80211_FC0_TYPE_MASK); |
| 4182 | gen_not(b0); |
| 4183 | b1 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS, |
| 4184 | IEEE80211_FC0_SUBTYPE_MASK); |
| 4185 | gen_not(b1); |
| 4186 | b2 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK, |
| 4187 | IEEE80211_FC0_SUBTYPE_MASK); |
| 4188 | gen_not(b2); |
| 4189 | gen_and(b1, b2); |
| 4190 | gen_or(b0, b2); |
| 4191 | b1 = gen_bcmp(OR_LINK, 10, 6, eaddr); |
| 4192 | gen_and(b2, b1); |
| 4193 | return b1; |
| 4194 | |
| 4195 | case Q_ADDR3: |
| 4196 | /* |
| 4197 | * Not present in control frames. |
| 4198 | */ |
| 4199 | b0 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_TYPE_CTL, |
| 4200 | IEEE80211_FC0_TYPE_MASK); |
| 4201 | gen_not(b0); |
| 4202 | b1 = gen_bcmp(OR_LINK, 16, 6, eaddr); |
| 4203 | gen_and(b0, b1); |
| 4204 | return b1; |
| 4205 | |
| 4206 | case Q_ADDR4: |
| 4207 | /* |
| 4208 | * Present only if the direction mask has both "From DS" |
| 4209 | * and "To DS" set. Neither control frames nor management |
| 4210 | * frames should have both of those set, so we don't |
| 4211 | * check the frame type. |
| 4212 | */ |
| 4213 | b0 = gen_mcmp(OR_LINK, 1, BPF_B, |
| 4214 | IEEE80211_FC1_DIR_DSTODS, IEEE80211_FC1_DIR_MASK); |
| 4215 | b1 = gen_bcmp(OR_LINK, 24, 6, eaddr); |
| 4216 | gen_and(b0, b1); |
| 4217 | return b1; |
| 4218 | |
| 4219 | case Q_AND: |
| 4220 | b0 = gen_wlanhostop(eaddr, Q_SRC); |
| 4221 | b1 = gen_wlanhostop(eaddr, Q_DST); |
| 4222 | gen_and(b0, b1); |
| 4223 | return b1; |
| 4224 | |
| 4225 | case Q_DEFAULT: |
| 4226 | case Q_OR: |
| 4227 | b0 = gen_wlanhostop(eaddr, Q_SRC); |
| 4228 | b1 = gen_wlanhostop(eaddr, Q_DST); |
| 4229 | gen_or(b0, b1); |
| 4230 | return b1; |
| 4231 | } |
| 4232 | abort(); |
| 4233 | /* NOTREACHED */ |
| 4234 | } |
| 4235 | |
| 4236 | /* |
| 4237 | * Like gen_ehostop, but for RFC 2625 IP-over-Fibre-Channel. |
| 4238 | * (We assume that the addresses are IEEE 48-bit MAC addresses, |
| 4239 | * as the RFC states.) |
| 4240 | */ |
| 4241 | static struct block * |
| 4242 | gen_ipfchostop(eaddr, dir) |
| 4243 | register const u_char *eaddr; |
| 4244 | register int dir; |
| 4245 | { |
| 4246 | register struct block *b0, *b1; |
| 4247 | |
| 4248 | switch (dir) { |
| 4249 | case Q_SRC: |
| 4250 | return gen_bcmp(OR_LINK, 10, 6, eaddr); |
| 4251 | |
| 4252 | case Q_DST: |
| 4253 | return gen_bcmp(OR_LINK, 2, 6, eaddr); |
| 4254 | |
| 4255 | case Q_AND: |
| 4256 | b0 = gen_ipfchostop(eaddr, Q_SRC); |
| 4257 | b1 = gen_ipfchostop(eaddr, Q_DST); |
| 4258 | gen_and(b0, b1); |
| 4259 | return b1; |
| 4260 | |
| 4261 | case Q_DEFAULT: |
| 4262 | case Q_OR: |
| 4263 | b0 = gen_ipfchostop(eaddr, Q_SRC); |
| 4264 | b1 = gen_ipfchostop(eaddr, Q_DST); |
| 4265 | gen_or(b0, b1); |
| 4266 | return b1; |
| 4267 | |
| 4268 | case Q_ADDR1: |
| 4269 | bpf_error("'addr1' is only supported on 802.11"); |
| 4270 | break; |
| 4271 | |
| 4272 | case Q_ADDR2: |
| 4273 | bpf_error("'addr2' is only supported on 802.11"); |
| 4274 | break; |
| 4275 | |
| 4276 | case Q_ADDR3: |
| 4277 | bpf_error("'addr3' is only supported on 802.11"); |
| 4278 | break; |
| 4279 | |
| 4280 | case Q_ADDR4: |
| 4281 | bpf_error("'addr4' is only supported on 802.11"); |
| 4282 | break; |
| 4283 | |
| 4284 | case Q_RA: |
| 4285 | bpf_error("'ra' is only supported on 802.11"); |
| 4286 | break; |
| 4287 | |
| 4288 | case Q_TA: |
| 4289 | bpf_error("'ta' is only supported on 802.11"); |
| 4290 | break; |
| 4291 | } |
| 4292 | abort(); |
| 4293 | /* NOTREACHED */ |
| 4294 | } |
| 4295 | |
| 4296 | /* |
| 4297 | * This is quite tricky because there may be pad bytes in front of the |
| 4298 | * DECNET header, and then there are two possible data packet formats that |
| 4299 | * carry both src and dst addresses, plus 5 packet types in a format that |
| 4300 | * carries only the src node, plus 2 types that use a different format and |
| 4301 | * also carry just the src node. |
| 4302 | * |
| 4303 | * Yuck. |
| 4304 | * |
| 4305 | * Instead of doing those all right, we just look for data packets with |
| 4306 | * 0 or 1 bytes of padding. If you want to look at other packets, that |
| 4307 | * will require a lot more hacking. |
| 4308 | * |
| 4309 | * To add support for filtering on DECNET "areas" (network numbers) |
| 4310 | * one would want to add a "mask" argument to this routine. That would |
| 4311 | * make the filter even more inefficient, although one could be clever |
| 4312 | * and not generate masking instructions if the mask is 0xFFFF. |
| 4313 | */ |
| 4314 | static struct block * |
| 4315 | gen_dnhostop(addr, dir) |
| 4316 | bpf_u_int32 addr; |
| 4317 | int dir; |
| 4318 | { |
| 4319 | struct block *b0, *b1, *b2, *tmp; |
| 4320 | u_int offset_lh; /* offset if long header is received */ |
| 4321 | u_int offset_sh; /* offset if short header is received */ |
| 4322 | |
| 4323 | switch (dir) { |
| 4324 | |
| 4325 | case Q_DST: |
| 4326 | offset_sh = 1; /* follows flags */ |
| 4327 | offset_lh = 7; /* flgs,darea,dsubarea,HIORD */ |
| 4328 | break; |
| 4329 | |
| 4330 | case Q_SRC: |
| 4331 | offset_sh = 3; /* follows flags, dstnode */ |
| 4332 | offset_lh = 15; /* flgs,darea,dsubarea,did,sarea,ssub,HIORD */ |
| 4333 | break; |
| 4334 | |
| 4335 | case Q_AND: |
| 4336 | /* Inefficient because we do our Calvinball dance twice */ |
| 4337 | b0 = gen_dnhostop(addr, Q_SRC); |
| 4338 | b1 = gen_dnhostop(addr, Q_DST); |
| 4339 | gen_and(b0, b1); |
| 4340 | return b1; |
| 4341 | |
| 4342 | case Q_OR: |
| 4343 | case Q_DEFAULT: |
| 4344 | /* Inefficient because we do our Calvinball dance twice */ |
| 4345 | b0 = gen_dnhostop(addr, Q_SRC); |
| 4346 | b1 = gen_dnhostop(addr, Q_DST); |
| 4347 | gen_or(b0, b1); |
| 4348 | return b1; |
| 4349 | |
| 4350 | case Q_ISO: |
| 4351 | bpf_error("ISO host filtering not implemented"); |
| 4352 | |
| 4353 | default: |
| 4354 | abort(); |
| 4355 | } |
| 4356 | b0 = gen_linktype(ETHERTYPE_DN); |
| 4357 | /* Check for pad = 1, long header case */ |
| 4358 | tmp = gen_mcmp(OR_NET, 2, BPF_H, |
| 4359 | (bpf_int32)ntohs(0x0681), (bpf_int32)ntohs(0x07FF)); |
| 4360 | b1 = gen_cmp(OR_NET, 2 + 1 + offset_lh, |
| 4361 | BPF_H, (bpf_int32)ntohs((u_short)addr)); |
| 4362 | gen_and(tmp, b1); |
| 4363 | /* Check for pad = 0, long header case */ |
| 4364 | tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x06, (bpf_int32)0x7); |
| 4365 | b2 = gen_cmp(OR_NET, 2 + offset_lh, BPF_H, (bpf_int32)ntohs((u_short)addr)); |
| 4366 | gen_and(tmp, b2); |
| 4367 | gen_or(b2, b1); |
| 4368 | /* Check for pad = 1, short header case */ |
| 4369 | tmp = gen_mcmp(OR_NET, 2, BPF_H, |
| 4370 | (bpf_int32)ntohs(0x0281), (bpf_int32)ntohs(0x07FF)); |
| 4371 | b2 = gen_cmp(OR_NET, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr)); |
| 4372 | gen_and(tmp, b2); |
| 4373 | gen_or(b2, b1); |
| 4374 | /* Check for pad = 0, short header case */ |
| 4375 | tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x02, (bpf_int32)0x7); |
| 4376 | b2 = gen_cmp(OR_NET, 2 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr)); |
| 4377 | gen_and(tmp, b2); |
| 4378 | gen_or(b2, b1); |
| 4379 | |
| 4380 | /* Combine with test for linktype */ |
| 4381 | gen_and(b0, b1); |
| 4382 | return b1; |
| 4383 | } |
| 4384 | |
| 4385 | /* |
| 4386 | * Generate a check for IPv4 or IPv6 for MPLS-encapsulated packets; |
| 4387 | * test the bottom-of-stack bit, and then check the version number |
| 4388 | * field in the IP header. |
| 4389 | */ |
| 4390 | static struct block * |
| 4391 | gen_mpls_linktype(proto) |
| 4392 | int proto; |
| 4393 | { |
| 4394 | struct block *b0, *b1; |
| 4395 | |
| 4396 | switch (proto) { |
| 4397 | |
| 4398 | case Q_IP: |
| 4399 | /* match the bottom-of-stack bit */ |
| 4400 | b0 = gen_mcmp(OR_NET, -2, BPF_B, 0x01, 0x01); |
| 4401 | /* match the IPv4 version number */ |
| 4402 | b1 = gen_mcmp(OR_NET, 0, BPF_B, 0x40, 0xf0); |
| 4403 | gen_and(b0, b1); |
| 4404 | return b1; |
| 4405 | |
| 4406 | case Q_IPV6: |
| 4407 | /* match the bottom-of-stack bit */ |
| 4408 | b0 = gen_mcmp(OR_NET, -2, BPF_B, 0x01, 0x01); |
| 4409 | /* match the IPv4 version number */ |
| 4410 | b1 = gen_mcmp(OR_NET, 0, BPF_B, 0x60, 0xf0); |
| 4411 | gen_and(b0, b1); |
| 4412 | return b1; |
| 4413 | |
| 4414 | default: |
| 4415 | abort(); |
| 4416 | } |
| 4417 | } |
| 4418 | |
| 4419 | static struct block * |
| 4420 | gen_host(addr, mask, proto, dir, type) |
| 4421 | bpf_u_int32 addr; |
| 4422 | bpf_u_int32 mask; |
| 4423 | int proto; |
| 4424 | int dir; |
| 4425 | int type; |
| 4426 | { |
| 4427 | struct block *b0, *b1; |
| 4428 | const char *typestr; |
| 4429 | |
| 4430 | if (type == Q_NET) |
| 4431 | typestr = "net"; |
| 4432 | else |
| 4433 | typestr = "host"; |
| 4434 | |
| 4435 | switch (proto) { |
| 4436 | |
| 4437 | case Q_DEFAULT: |
| 4438 | b0 = gen_host(addr, mask, Q_IP, dir, type); |
| 4439 | /* |
| 4440 | * Only check for non-IPv4 addresses if we're not |
| 4441 | * checking MPLS-encapsulated packets. |
| 4442 | */ |
| 4443 | if (label_stack_depth == 0) { |
| 4444 | b1 = gen_host(addr, mask, Q_ARP, dir, type); |
| 4445 | gen_or(b0, b1); |
| 4446 | b0 = gen_host(addr, mask, Q_RARP, dir, type); |
| 4447 | gen_or(b1, b0); |
| 4448 | } |
| 4449 | return b0; |
| 4450 | |
| 4451 | case Q_IP: |
| 4452 | return gen_hostop(addr, mask, dir, ETHERTYPE_IP, 12, 16); |
| 4453 | |
| 4454 | case Q_RARP: |
| 4455 | return gen_hostop(addr, mask, dir, ETHERTYPE_REVARP, 14, 24); |
| 4456 | |
| 4457 | case Q_ARP: |
| 4458 | return gen_hostop(addr, mask, dir, ETHERTYPE_ARP, 14, 24); |
| 4459 | |
| 4460 | case Q_TCP: |
| 4461 | bpf_error("'tcp' modifier applied to %s", typestr); |
| 4462 | |
| 4463 | case Q_SCTP: |
| 4464 | bpf_error("'sctp' modifier applied to %s", typestr); |
| 4465 | |
| 4466 | case Q_UDP: |
| 4467 | bpf_error("'udp' modifier applied to %s", typestr); |
| 4468 | |
| 4469 | case Q_ICMP: |
| 4470 | bpf_error("'icmp' modifier applied to %s", typestr); |
| 4471 | |
| 4472 | case Q_IGMP: |
| 4473 | bpf_error("'igmp' modifier applied to %s", typestr); |
| 4474 | |
| 4475 | case Q_IGRP: |
| 4476 | bpf_error("'igrp' modifier applied to %s", typestr); |
| 4477 | |
| 4478 | case Q_PIM: |
| 4479 | bpf_error("'pim' modifier applied to %s", typestr); |
| 4480 | |
| 4481 | case Q_VRRP: |
| 4482 | bpf_error("'vrrp' modifier applied to %s", typestr); |
| 4483 | |
| 4484 | case Q_CARP: |
| 4485 | bpf_error("'carp' modifier applied to %s", typestr); |
| 4486 | |
| 4487 | case Q_ATALK: |
| 4488 | bpf_error("ATALK host filtering not implemented"); |
| 4489 | |
| 4490 | case Q_AARP: |
| 4491 | bpf_error("AARP host filtering not implemented"); |
| 4492 | |
| 4493 | case Q_DECNET: |
| 4494 | return gen_dnhostop(addr, dir); |
| 4495 | |
| 4496 | case Q_SCA: |
| 4497 | bpf_error("SCA host filtering not implemented"); |
| 4498 | |
| 4499 | case Q_LAT: |
| 4500 | bpf_error("LAT host filtering not implemented"); |
| 4501 | |
| 4502 | case Q_MOPDL: |
| 4503 | bpf_error("MOPDL host filtering not implemented"); |
| 4504 | |
| 4505 | case Q_MOPRC: |
| 4506 | bpf_error("MOPRC host filtering not implemented"); |
| 4507 | |
| 4508 | #ifdef INET6 |
| 4509 | case Q_IPV6: |
| 4510 | bpf_error("'ip6' modifier applied to ip host"); |
| 4511 | |
| 4512 | case Q_ICMPV6: |
| 4513 | bpf_error("'icmp6' modifier applied to %s", typestr); |
| 4514 | #endif /* INET6 */ |
| 4515 | |
| 4516 | case Q_AH: |
| 4517 | bpf_error("'ah' modifier applied to %s", typestr); |
| 4518 | |
| 4519 | case Q_ESP: |
| 4520 | bpf_error("'esp' modifier applied to %s", typestr); |
| 4521 | |
| 4522 | case Q_ISO: |
| 4523 | bpf_error("ISO host filtering not implemented"); |
| 4524 | |
| 4525 | case Q_ESIS: |
| 4526 | bpf_error("'esis' modifier applied to %s", typestr); |
| 4527 | |
| 4528 | case Q_ISIS: |
| 4529 | bpf_error("'isis' modifier applied to %s", typestr); |
| 4530 | |
| 4531 | case Q_CLNP: |
| 4532 | bpf_error("'clnp' modifier applied to %s", typestr); |
| 4533 | |
| 4534 | case Q_STP: |
| 4535 | bpf_error("'stp' modifier applied to %s", typestr); |
| 4536 | |
| 4537 | case Q_IPX: |
| 4538 | bpf_error("IPX host filtering not implemented"); |
| 4539 | |
| 4540 | case Q_NETBEUI: |
| 4541 | bpf_error("'netbeui' modifier applied to %s", typestr); |
| 4542 | |
| 4543 | case Q_RADIO: |
| 4544 | bpf_error("'radio' modifier applied to %s", typestr); |
| 4545 | |
| 4546 | default: |
| 4547 | abort(); |
| 4548 | } |
| 4549 | /* NOTREACHED */ |
| 4550 | } |
| 4551 | |
| 4552 | #ifdef INET6 |
| 4553 | static struct block * |
| 4554 | gen_host6(addr, mask, proto, dir, type) |
| 4555 | struct in6_addr *addr; |
| 4556 | struct in6_addr *mask; |
| 4557 | int proto; |
| 4558 | int dir; |
| 4559 | int type; |
| 4560 | { |
| 4561 | const char *typestr; |
| 4562 | |
| 4563 | if (type == Q_NET) |
| 4564 | typestr = "net"; |
| 4565 | else |
| 4566 | typestr = "host"; |
| 4567 | |
| 4568 | switch (proto) { |
| 4569 | |
| 4570 | case Q_DEFAULT: |
| 4571 | return gen_host6(addr, mask, Q_IPV6, dir, type); |
| 4572 | |
| 4573 | case Q_IP: |
| 4574 | bpf_error("'ip' modifier applied to ip6 %s", typestr); |
| 4575 | |
| 4576 | case Q_RARP: |
| 4577 | bpf_error("'rarp' modifier applied to ip6 %s", typestr); |
| 4578 | |
| 4579 | case Q_ARP: |
| 4580 | bpf_error("'arp' modifier applied to ip6 %s", typestr); |
| 4581 | |
| 4582 | case Q_SCTP: |
| 4583 | bpf_error("'sctp' modifier applied to %s", typestr); |
| 4584 | |
| 4585 | case Q_TCP: |
| 4586 | bpf_error("'tcp' modifier applied to %s", typestr); |
| 4587 | |
| 4588 | case Q_UDP: |
| 4589 | bpf_error("'udp' modifier applied to %s", typestr); |
| 4590 | |
| 4591 | case Q_ICMP: |
| 4592 | bpf_error("'icmp' modifier applied to %s", typestr); |
| 4593 | |
| 4594 | case Q_IGMP: |
| 4595 | bpf_error("'igmp' modifier applied to %s", typestr); |
| 4596 | |
| 4597 | case Q_IGRP: |
| 4598 | bpf_error("'igrp' modifier applied to %s", typestr); |
| 4599 | |
| 4600 | case Q_PIM: |
| 4601 | bpf_error("'pim' modifier applied to %s", typestr); |
| 4602 | |
| 4603 | case Q_VRRP: |
| 4604 | bpf_error("'vrrp' modifier applied to %s", typestr); |
| 4605 | |
| 4606 | case Q_CARP: |
| 4607 | bpf_error("'carp' modifier applied to %s", typestr); |
| 4608 | |
| 4609 | case Q_ATALK: |
| 4610 | bpf_error("ATALK host filtering not implemented"); |
| 4611 | |
| 4612 | case Q_AARP: |
| 4613 | bpf_error("AARP host filtering not implemented"); |
| 4614 | |
| 4615 | case Q_DECNET: |
| 4616 | bpf_error("'decnet' modifier applied to ip6 %s", typestr); |
| 4617 | |
| 4618 | case Q_SCA: |
| 4619 | bpf_error("SCA host filtering not implemented"); |
| 4620 | |
| 4621 | case Q_LAT: |
| 4622 | bpf_error("LAT host filtering not implemented"); |
| 4623 | |
| 4624 | case Q_MOPDL: |
| 4625 | bpf_error("MOPDL host filtering not implemented"); |
| 4626 | |
| 4627 | case Q_MOPRC: |
| 4628 | bpf_error("MOPRC host filtering not implemented"); |
| 4629 | |
| 4630 | case Q_IPV6: |
| 4631 | return gen_hostop6(addr, mask, dir, ETHERTYPE_IPV6, 8, 24); |
| 4632 | |
| 4633 | case Q_ICMPV6: |
| 4634 | bpf_error("'icmp6' modifier applied to %s", typestr); |
| 4635 | |
| 4636 | case Q_AH: |
| 4637 | bpf_error("'ah' modifier applied to %s", typestr); |
| 4638 | |
| 4639 | case Q_ESP: |
| 4640 | bpf_error("'esp' modifier applied to %s", typestr); |
| 4641 | |
| 4642 | case Q_ISO: |
| 4643 | bpf_error("ISO host filtering not implemented"); |
| 4644 | |
| 4645 | case Q_ESIS: |
| 4646 | bpf_error("'esis' modifier applied to %s", typestr); |
| 4647 | |
| 4648 | case Q_ISIS: |
| 4649 | bpf_error("'isis' modifier applied to %s", typestr); |
| 4650 | |
| 4651 | case Q_CLNP: |
| 4652 | bpf_error("'clnp' modifier applied to %s", typestr); |
| 4653 | |
| 4654 | case Q_STP: |
| 4655 | bpf_error("'stp' modifier applied to %s", typestr); |
| 4656 | |
| 4657 | case Q_IPX: |
| 4658 | bpf_error("IPX host filtering not implemented"); |
| 4659 | |
| 4660 | case Q_NETBEUI: |
| 4661 | bpf_error("'netbeui' modifier applied to %s", typestr); |
| 4662 | |
| 4663 | case Q_RADIO: |
| 4664 | bpf_error("'radio' modifier applied to %s", typestr); |
| 4665 | |
| 4666 | default: |
| 4667 | abort(); |
| 4668 | } |
| 4669 | /* NOTREACHED */ |
| 4670 | } |
| 4671 | #endif /*INET6*/ |
| 4672 | |
| 4673 | #ifndef INET6 |
| 4674 | static struct block * |
| 4675 | gen_gateway(eaddr, alist, proto, dir) |
| 4676 | const u_char *eaddr; |
| 4677 | bpf_u_int32 **alist; |
| 4678 | int proto; |
| 4679 | int dir; |
| 4680 | { |
| 4681 | struct block *b0, *b1, *tmp; |
| 4682 | |
| 4683 | if (dir != 0) |
| 4684 | bpf_error("direction applied to 'gateway'"); |
| 4685 | |
| 4686 | switch (proto) { |
| 4687 | case Q_DEFAULT: |
| 4688 | case Q_IP: |
| 4689 | case Q_ARP: |
| 4690 | case Q_RARP: |
| 4691 | switch (linktype) { |
| 4692 | case DLT_EN10MB: |
| 4693 | case DLT_NETANALYZER: |
| 4694 | case DLT_NETANALYZER_TRANSPARENT: |
| 4695 | b0 = gen_ehostop(eaddr, Q_OR); |
| 4696 | break; |
| 4697 | case DLT_FDDI: |
| 4698 | b0 = gen_fhostop(eaddr, Q_OR); |
| 4699 | break; |
| 4700 | case DLT_IEEE802: |
| 4701 | b0 = gen_thostop(eaddr, Q_OR); |
| 4702 | break; |
| 4703 | case DLT_IEEE802_11: |
| 4704 | case DLT_PRISM_HEADER: |
| 4705 | case DLT_IEEE802_11_RADIO_AVS: |
| 4706 | case DLT_IEEE802_11_RADIO: |
| 4707 | case DLT_PPI: |
| 4708 | b0 = gen_wlanhostop(eaddr, Q_OR); |
| 4709 | break; |
| 4710 | case DLT_SUNATM: |
| 4711 | if (!is_lane) |
| 4712 | bpf_error( |
| 4713 | "'gateway' supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel"); |
| 4714 | /* |
| 4715 | * Check that the packet doesn't begin with an |
| 4716 | * LE Control marker. (We've already generated |
| 4717 | * a test for LANE.) |
| 4718 | */ |
| 4719 | b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, |
| 4720 | BPF_H, 0xFF00); |
| 4721 | gen_not(b1); |
| 4722 | |
| 4723 | /* |
| 4724 | * Now check the MAC address. |
| 4725 | */ |
| 4726 | b0 = gen_ehostop(eaddr, Q_OR); |
| 4727 | gen_and(b1, b0); |
| 4728 | break; |
| 4729 | case DLT_IP_OVER_FC: |
| 4730 | b0 = gen_ipfchostop(eaddr, Q_OR); |
| 4731 | break; |
| 4732 | default: |
| 4733 | bpf_error( |
| 4734 | "'gateway' supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel"); |
| 4735 | } |
| 4736 | b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR, Q_HOST); |
| 4737 | while (*alist) { |
| 4738 | tmp = gen_host(**alist++, 0xffffffff, proto, Q_OR, |
| 4739 | Q_HOST); |
| 4740 | gen_or(b1, tmp); |
| 4741 | b1 = tmp; |
| 4742 | } |
| 4743 | gen_not(b1); |
| 4744 | gen_and(b0, b1); |
| 4745 | return b1; |
| 4746 | } |
| 4747 | bpf_error("illegal modifier of 'gateway'"); |
| 4748 | /* NOTREACHED */ |
| 4749 | } |
| 4750 | #endif |
| 4751 | |
| 4752 | struct block * |
| 4753 | gen_proto_abbrev(proto) |
| 4754 | int proto; |
| 4755 | { |
| 4756 | struct block *b0; |
| 4757 | struct block *b1; |
| 4758 | |
| 4759 | switch (proto) { |
| 4760 | |
| 4761 | case Q_SCTP: |
| 4762 | b1 = gen_proto(IPPROTO_SCTP, Q_IP, Q_DEFAULT); |
| 4763 | #ifdef INET6 |
| 4764 | b0 = gen_proto(IPPROTO_SCTP, Q_IPV6, Q_DEFAULT); |
| 4765 | gen_or(b0, b1); |
| 4766 | #endif |
| 4767 | break; |
| 4768 | |
| 4769 | case Q_TCP: |
| 4770 | b1 = gen_proto(IPPROTO_TCP, Q_IP, Q_DEFAULT); |
| 4771 | #ifdef INET6 |
| 4772 | b0 = gen_proto(IPPROTO_TCP, Q_IPV6, Q_DEFAULT); |
| 4773 | gen_or(b0, b1); |
| 4774 | #endif |
| 4775 | break; |
| 4776 | |
| 4777 | case Q_UDP: |
| 4778 | b1 = gen_proto(IPPROTO_UDP, Q_IP, Q_DEFAULT); |
| 4779 | #ifdef INET6 |
| 4780 | b0 = gen_proto(IPPROTO_UDP, Q_IPV6, Q_DEFAULT); |
| 4781 | gen_or(b0, b1); |
| 4782 | #endif |
| 4783 | break; |
| 4784 | |
| 4785 | case Q_ICMP: |
| 4786 | b1 = gen_proto(IPPROTO_ICMP, Q_IP, Q_DEFAULT); |
| 4787 | break; |
| 4788 | |
| 4789 | #ifndef IPPROTO_IGMP |
| 4790 | #define IPPROTO_IGMP 2 |
| 4791 | #endif |
| 4792 | |
| 4793 | case Q_IGMP: |
| 4794 | b1 = gen_proto(IPPROTO_IGMP, Q_IP, Q_DEFAULT); |
| 4795 | break; |
| 4796 | |
| 4797 | #ifndef IPPROTO_IGRP |
| 4798 | #define IPPROTO_IGRP 9 |
| 4799 | #endif |
| 4800 | case Q_IGRP: |
| 4801 | b1 = gen_proto(IPPROTO_IGRP, Q_IP, Q_DEFAULT); |
| 4802 | break; |
| 4803 | |
| 4804 | #ifndef IPPROTO_PIM |
| 4805 | #define IPPROTO_PIM 103 |
| 4806 | #endif |
| 4807 | |
| 4808 | case Q_PIM: |
| 4809 | b1 = gen_proto(IPPROTO_PIM, Q_IP, Q_DEFAULT); |
| 4810 | #ifdef INET6 |
| 4811 | b0 = gen_proto(IPPROTO_PIM, Q_IPV6, Q_DEFAULT); |
| 4812 | gen_or(b0, b1); |
| 4813 | #endif |
| 4814 | break; |
| 4815 | |
| 4816 | #ifndef IPPROTO_VRRP |
| 4817 | #define IPPROTO_VRRP 112 |
| 4818 | #endif |
| 4819 | |
| 4820 | case Q_VRRP: |
| 4821 | b1 = gen_proto(IPPROTO_VRRP, Q_IP, Q_DEFAULT); |
| 4822 | break; |
| 4823 | |
| 4824 | #ifndef IPPROTO_CARP |
| 4825 | #define IPPROTO_CARP 112 |
| 4826 | #endif |
| 4827 | |
| 4828 | case Q_CARP: |
| 4829 | b1 = gen_proto(IPPROTO_CARP, Q_IP, Q_DEFAULT); |
| 4830 | break; |
| 4831 | |
| 4832 | case Q_IP: |
| 4833 | b1 = gen_linktype(ETHERTYPE_IP); |
| 4834 | break; |
| 4835 | |
| 4836 | case Q_ARP: |
| 4837 | b1 = gen_linktype(ETHERTYPE_ARP); |
| 4838 | break; |
| 4839 | |
| 4840 | case Q_RARP: |
| 4841 | b1 = gen_linktype(ETHERTYPE_REVARP); |
| 4842 | break; |
| 4843 | |
| 4844 | case Q_LINK: |
| 4845 | bpf_error("link layer applied in wrong context"); |
| 4846 | |
| 4847 | case Q_ATALK: |
| 4848 | b1 = gen_linktype(ETHERTYPE_ATALK); |
| 4849 | break; |
| 4850 | |
| 4851 | case Q_AARP: |
| 4852 | b1 = gen_linktype(ETHERTYPE_AARP); |
| 4853 | break; |
| 4854 | |
| 4855 | case Q_DECNET: |
| 4856 | b1 = gen_linktype(ETHERTYPE_DN); |
| 4857 | break; |
| 4858 | |
| 4859 | case Q_SCA: |
| 4860 | b1 = gen_linktype(ETHERTYPE_SCA); |
| 4861 | break; |
| 4862 | |
| 4863 | case Q_LAT: |
| 4864 | b1 = gen_linktype(ETHERTYPE_LAT); |
| 4865 | break; |
| 4866 | |
| 4867 | case Q_MOPDL: |
| 4868 | b1 = gen_linktype(ETHERTYPE_MOPDL); |
| 4869 | break; |
| 4870 | |
| 4871 | case Q_MOPRC: |
| 4872 | b1 = gen_linktype(ETHERTYPE_MOPRC); |
| 4873 | break; |
| 4874 | |
| 4875 | #ifdef INET6 |
| 4876 | case Q_IPV6: |
| 4877 | b1 = gen_linktype(ETHERTYPE_IPV6); |
| 4878 | break; |
| 4879 | |
| 4880 | #ifndef IPPROTO_ICMPV6 |
| 4881 | #define IPPROTO_ICMPV6 58 |
| 4882 | #endif |
| 4883 | case Q_ICMPV6: |
| 4884 | b1 = gen_proto(IPPROTO_ICMPV6, Q_IPV6, Q_DEFAULT); |
| 4885 | break; |
| 4886 | #endif /* INET6 */ |
| 4887 | |
| 4888 | #ifndef IPPROTO_AH |
| 4889 | #define IPPROTO_AH 51 |
| 4890 | #endif |
| 4891 | case Q_AH: |
| 4892 | b1 = gen_proto(IPPROTO_AH, Q_IP, Q_DEFAULT); |
| 4893 | #ifdef INET6 |
| 4894 | b0 = gen_proto(IPPROTO_AH, Q_IPV6, Q_DEFAULT); |
| 4895 | gen_or(b0, b1); |
| 4896 | #endif |
| 4897 | break; |
| 4898 | |
| 4899 | #ifndef IPPROTO_ESP |
| 4900 | #define IPPROTO_ESP 50 |
| 4901 | #endif |
| 4902 | case Q_ESP: |
| 4903 | b1 = gen_proto(IPPROTO_ESP, Q_IP, Q_DEFAULT); |
| 4904 | #ifdef INET6 |
| 4905 | b0 = gen_proto(IPPROTO_ESP, Q_IPV6, Q_DEFAULT); |
| 4906 | gen_or(b0, b1); |
| 4907 | #endif |
| 4908 | break; |
| 4909 | |
| 4910 | case Q_ISO: |
| 4911 | b1 = gen_linktype(LLCSAP_ISONS); |
| 4912 | break; |
| 4913 | |
| 4914 | case Q_ESIS: |
| 4915 | b1 = gen_proto(ISO9542_ESIS, Q_ISO, Q_DEFAULT); |
| 4916 | break; |
| 4917 | |
| 4918 | case Q_ISIS: |
| 4919 | b1 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT); |
| 4920 | break; |
| 4921 | |
| 4922 | case Q_ISIS_L1: /* all IS-IS Level1 PDU-Types */ |
| 4923 | b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT); |
| 4924 | b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */ |
| 4925 | gen_or(b0, b1); |
| 4926 | b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT); |
| 4927 | gen_or(b0, b1); |
| 4928 | b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT); |
| 4929 | gen_or(b0, b1); |
| 4930 | b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT); |
| 4931 | gen_or(b0, b1); |
| 4932 | break; |
| 4933 | |
| 4934 | case Q_ISIS_L2: /* all IS-IS Level2 PDU-Types */ |
| 4935 | b0 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT); |
| 4936 | b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */ |
| 4937 | gen_or(b0, b1); |
| 4938 | b0 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT); |
| 4939 | gen_or(b0, b1); |
| 4940 | b0 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT); |
| 4941 | gen_or(b0, b1); |
| 4942 | b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT); |
| 4943 | gen_or(b0, b1); |
| 4944 | break; |
| 4945 | |
| 4946 | case Q_ISIS_IIH: /* all IS-IS Hello PDU-Types */ |
| 4947 | b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT); |
| 4948 | b1 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT); |
| 4949 | gen_or(b0, b1); |
| 4950 | b0 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); |
| 4951 | gen_or(b0, b1); |
| 4952 | break; |
| 4953 | |
| 4954 | case Q_ISIS_LSP: |
| 4955 | b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT); |
| 4956 | b1 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT); |
| 4957 | gen_or(b0, b1); |
| 4958 | break; |
| 4959 | |
| 4960 | case Q_ISIS_SNP: |
| 4961 | b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT); |
| 4962 | b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT); |
| 4963 | gen_or(b0, b1); |
| 4964 | b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT); |
| 4965 | gen_or(b0, b1); |
| 4966 | b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT); |
| 4967 | gen_or(b0, b1); |
| 4968 | break; |
| 4969 | |
| 4970 | case Q_ISIS_CSNP: |
| 4971 | b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT); |
| 4972 | b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT); |
| 4973 | gen_or(b0, b1); |
| 4974 | break; |
| 4975 | |
| 4976 | case Q_ISIS_PSNP: |
| 4977 | b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT); |
| 4978 | b1 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT); |
| 4979 | gen_or(b0, b1); |
| 4980 | break; |
| 4981 | |
| 4982 | case Q_CLNP: |
| 4983 | b1 = gen_proto(ISO8473_CLNP, Q_ISO, Q_DEFAULT); |
| 4984 | break; |
| 4985 | |
| 4986 | case Q_STP: |
| 4987 | b1 = gen_linktype(LLCSAP_8021D); |
| 4988 | break; |
| 4989 | |
| 4990 | case Q_IPX: |
| 4991 | b1 = gen_linktype(LLCSAP_IPX); |
| 4992 | break; |
| 4993 | |
| 4994 | case Q_NETBEUI: |
| 4995 | b1 = gen_linktype(LLCSAP_NETBEUI); |
| 4996 | break; |
| 4997 | |
| 4998 | case Q_RADIO: |
| 4999 | bpf_error("'radio' is not a valid protocol type"); |
| 5000 | |
| 5001 | default: |
| 5002 | abort(); |
| 5003 | } |
| 5004 | return b1; |
| 5005 | } |
| 5006 | |
| 5007 | static struct block * |
| 5008 | gen_ipfrag() |
| 5009 | { |
| 5010 | struct slist *s; |
| 5011 | struct block *b; |
| 5012 | |
| 5013 | /* not IPv4 frag other than the first frag */ |
| 5014 | s = gen_load_a(OR_NET, 6, BPF_H); |
| 5015 | b = new_block(JMP(BPF_JSET)); |
| 5016 | b->s.k = 0x1fff; |
| 5017 | b->stmts = s; |
| 5018 | gen_not(b); |
| 5019 | |
| 5020 | return b; |
| 5021 | } |
| 5022 | |
| 5023 | /* |
| 5024 | * Generate a comparison to a port value in the transport-layer header |
| 5025 | * at the specified offset from the beginning of that header. |
| 5026 | * |
| 5027 | * XXX - this handles a variable-length prefix preceding the link-layer |
| 5028 | * header, such as the radiotap or AVS radio prefix, but doesn't handle |
| 5029 | * variable-length link-layer headers (such as Token Ring or 802.11 |
| 5030 | * headers). |
| 5031 | */ |
| 5032 | static struct block * |
| 5033 | gen_portatom(off, v) |
| 5034 | int off; |
| 5035 | bpf_int32 v; |
| 5036 | { |
| 5037 | return gen_cmp(OR_TRAN_IPV4, off, BPF_H, v); |
| 5038 | } |
| 5039 | |
| 5040 | #ifdef INET6 |
| 5041 | static struct block * |
| 5042 | gen_portatom6(off, v) |
| 5043 | int off; |
| 5044 | bpf_int32 v; |
| 5045 | { |
| 5046 | return gen_cmp(OR_TRAN_IPV6, off, BPF_H, v); |
| 5047 | } |
| 5048 | #endif/*INET6*/ |
| 5049 | |
| 5050 | struct block * |
| 5051 | gen_portop(port, proto, dir) |
| 5052 | int port, proto, dir; |
| 5053 | { |
| 5054 | struct block *b0, *b1, *tmp; |
| 5055 | |
| 5056 | /* ip proto 'proto' and not a fragment other than the first fragment */ |
| 5057 | tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto); |
| 5058 | b0 = gen_ipfrag(); |
| 5059 | gen_and(tmp, b0); |
| 5060 | |
| 5061 | switch (dir) { |
| 5062 | case Q_SRC: |
| 5063 | b1 = gen_portatom(0, (bpf_int32)port); |
| 5064 | break; |
| 5065 | |
| 5066 | case Q_DST: |
| 5067 | b1 = gen_portatom(2, (bpf_int32)port); |
| 5068 | break; |
| 5069 | |
| 5070 | case Q_OR: |
| 5071 | case Q_DEFAULT: |
| 5072 | tmp = gen_portatom(0, (bpf_int32)port); |
| 5073 | b1 = gen_portatom(2, (bpf_int32)port); |
| 5074 | gen_or(tmp, b1); |
| 5075 | break; |
| 5076 | |
| 5077 | case Q_AND: |
| 5078 | tmp = gen_portatom(0, (bpf_int32)port); |
| 5079 | b1 = gen_portatom(2, (bpf_int32)port); |
| 5080 | gen_and(tmp, b1); |
| 5081 | break; |
| 5082 | |
| 5083 | default: |
| 5084 | abort(); |
| 5085 | } |
| 5086 | gen_and(b0, b1); |
| 5087 | |
| 5088 | return b1; |
| 5089 | } |
| 5090 | |
| 5091 | static struct block * |
| 5092 | gen_port(port, ip_proto, dir) |
| 5093 | int port; |
| 5094 | int ip_proto; |
| 5095 | int dir; |
| 5096 | { |
| 5097 | struct block *b0, *b1, *tmp; |
| 5098 | |
| 5099 | /* |
| 5100 | * ether proto ip |
| 5101 | * |
| 5102 | * For FDDI, RFC 1188 says that SNAP encapsulation is used, |
| 5103 | * not LLC encapsulation with LLCSAP_IP. |
| 5104 | * |
| 5105 | * For IEEE 802 networks - which includes 802.5 token ring |
| 5106 | * (which is what DLT_IEEE802 means) and 802.11 - RFC 1042 |
| 5107 | * says that SNAP encapsulation is used, not LLC encapsulation |
| 5108 | * with LLCSAP_IP. |
| 5109 | * |
| 5110 | * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and |
| 5111 | * RFC 2225 say that SNAP encapsulation is used, not LLC |
| 5112 | * encapsulation with LLCSAP_IP. |
| 5113 | * |
| 5114 | * So we always check for ETHERTYPE_IP. |
| 5115 | */ |
| 5116 | b0 = gen_linktype(ETHERTYPE_IP); |
| 5117 | |
| 5118 | switch (ip_proto) { |
| 5119 | case IPPROTO_UDP: |
| 5120 | case IPPROTO_TCP: |
| 5121 | case IPPROTO_SCTP: |
| 5122 | b1 = gen_portop(port, ip_proto, dir); |
| 5123 | break; |
| 5124 | |
| 5125 | case PROTO_UNDEF: |
| 5126 | tmp = gen_portop(port, IPPROTO_TCP, dir); |
| 5127 | b1 = gen_portop(port, IPPROTO_UDP, dir); |
| 5128 | gen_or(tmp, b1); |
| 5129 | tmp = gen_portop(port, IPPROTO_SCTP, dir); |
| 5130 | gen_or(tmp, b1); |
| 5131 | break; |
| 5132 | |
| 5133 | default: |
| 5134 | abort(); |
| 5135 | } |
| 5136 | gen_and(b0, b1); |
| 5137 | return b1; |
| 5138 | } |
| 5139 | |
| 5140 | #ifdef INET6 |
| 5141 | struct block * |
| 5142 | gen_portop6(port, proto, dir) |
| 5143 | int port, proto, dir; |
| 5144 | { |
| 5145 | struct block *b0, *b1, *tmp; |
| 5146 | |
| 5147 | /* ip6 proto 'proto' */ |
| 5148 | /* XXX - catch the first fragment of a fragmented packet? */ |
| 5149 | b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto); |
| 5150 | |
| 5151 | switch (dir) { |
| 5152 | case Q_SRC: |
| 5153 | b1 = gen_portatom6(0, (bpf_int32)port); |
| 5154 | break; |
| 5155 | |
| 5156 | case Q_DST: |
| 5157 | b1 = gen_portatom6(2, (bpf_int32)port); |
| 5158 | break; |
| 5159 | |
| 5160 | case Q_OR: |
| 5161 | case Q_DEFAULT: |
| 5162 | tmp = gen_portatom6(0, (bpf_int32)port); |
| 5163 | b1 = gen_portatom6(2, (bpf_int32)port); |
| 5164 | gen_or(tmp, b1); |
| 5165 | break; |
| 5166 | |
| 5167 | case Q_AND: |
| 5168 | tmp = gen_portatom6(0, (bpf_int32)port); |
| 5169 | b1 = gen_portatom6(2, (bpf_int32)port); |
| 5170 | gen_and(tmp, b1); |
| 5171 | break; |
| 5172 | |
| 5173 | default: |
| 5174 | abort(); |
| 5175 | } |
| 5176 | gen_and(b0, b1); |
| 5177 | |
| 5178 | return b1; |
| 5179 | } |
| 5180 | |
| 5181 | static struct block * |
| 5182 | gen_port6(port, ip_proto, dir) |
| 5183 | int port; |
| 5184 | int ip_proto; |
| 5185 | int dir; |
| 5186 | { |
| 5187 | struct block *b0, *b1, *tmp; |
| 5188 | |
| 5189 | /* link proto ip6 */ |
| 5190 | b0 = gen_linktype(ETHERTYPE_IPV6); |
| 5191 | |
| 5192 | switch (ip_proto) { |
| 5193 | case IPPROTO_UDP: |
| 5194 | case IPPROTO_TCP: |
| 5195 | case IPPROTO_SCTP: |
| 5196 | b1 = gen_portop6(port, ip_proto, dir); |
| 5197 | break; |
| 5198 | |
| 5199 | case PROTO_UNDEF: |
| 5200 | tmp = gen_portop6(port, IPPROTO_TCP, dir); |
| 5201 | b1 = gen_portop6(port, IPPROTO_UDP, dir); |
| 5202 | gen_or(tmp, b1); |
| 5203 | tmp = gen_portop6(port, IPPROTO_SCTP, dir); |
| 5204 | gen_or(tmp, b1); |
| 5205 | break; |
| 5206 | |
| 5207 | default: |
| 5208 | abort(); |
| 5209 | } |
| 5210 | gen_and(b0, b1); |
| 5211 | return b1; |
| 5212 | } |
| 5213 | #endif /* INET6 */ |
| 5214 | |
| 5215 | /* gen_portrange code */ |
| 5216 | static struct block * |
| 5217 | gen_portrangeatom(off, v1, v2) |
| 5218 | int off; |
| 5219 | bpf_int32 v1, v2; |
| 5220 | { |
| 5221 | struct block *b1, *b2; |
| 5222 | |
| 5223 | if (v1 > v2) { |
| 5224 | /* |
| 5225 | * Reverse the order of the ports, so v1 is the lower one. |
| 5226 | */ |
| 5227 | bpf_int32 vtemp; |
| 5228 | |
| 5229 | vtemp = v1; |
| 5230 | v1 = v2; |
| 5231 | v2 = vtemp; |
| 5232 | } |
| 5233 | |
| 5234 | b1 = gen_cmp_ge(OR_TRAN_IPV4, off, BPF_H, v1); |
| 5235 | b2 = gen_cmp_le(OR_TRAN_IPV4, off, BPF_H, v2); |
| 5236 | |
| 5237 | gen_and(b1, b2); |
| 5238 | |
| 5239 | return b2; |
| 5240 | } |
| 5241 | |
| 5242 | struct block * |
| 5243 | gen_portrangeop(port1, port2, proto, dir) |
| 5244 | int port1, port2; |
| 5245 | int proto; |
| 5246 | int dir; |
| 5247 | { |
| 5248 | struct block *b0, *b1, *tmp; |
| 5249 | |
| 5250 | /* ip proto 'proto' and not a fragment other than the first fragment */ |
| 5251 | tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto); |
| 5252 | b0 = gen_ipfrag(); |
| 5253 | gen_and(tmp, b0); |
| 5254 | |
| 5255 | switch (dir) { |
| 5256 | case Q_SRC: |
| 5257 | b1 = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2); |
| 5258 | break; |
| 5259 | |
| 5260 | case Q_DST: |
| 5261 | b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2); |
| 5262 | break; |
| 5263 | |
| 5264 | case Q_OR: |
| 5265 | case Q_DEFAULT: |
| 5266 | tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2); |
| 5267 | b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2); |
| 5268 | gen_or(tmp, b1); |
| 5269 | break; |
| 5270 | |
| 5271 | case Q_AND: |
| 5272 | tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2); |
| 5273 | b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2); |
| 5274 | gen_and(tmp, b1); |
| 5275 | break; |
| 5276 | |
| 5277 | default: |
| 5278 | abort(); |
| 5279 | } |
| 5280 | gen_and(b0, b1); |
| 5281 | |
| 5282 | return b1; |
| 5283 | } |
| 5284 | |
| 5285 | static struct block * |
| 5286 | gen_portrange(port1, port2, ip_proto, dir) |
| 5287 | int port1, port2; |
| 5288 | int ip_proto; |
| 5289 | int dir; |
| 5290 | { |
| 5291 | struct block *b0, *b1, *tmp; |
| 5292 | |
| 5293 | /* link proto ip */ |
| 5294 | b0 = gen_linktype(ETHERTYPE_IP); |
| 5295 | |
| 5296 | switch (ip_proto) { |
| 5297 | case IPPROTO_UDP: |
| 5298 | case IPPROTO_TCP: |
| 5299 | case IPPROTO_SCTP: |
| 5300 | b1 = gen_portrangeop(port1, port2, ip_proto, dir); |
| 5301 | break; |
| 5302 | |
| 5303 | case PROTO_UNDEF: |
| 5304 | tmp = gen_portrangeop(port1, port2, IPPROTO_TCP, dir); |
| 5305 | b1 = gen_portrangeop(port1, port2, IPPROTO_UDP, dir); |
| 5306 | gen_or(tmp, b1); |
| 5307 | tmp = gen_portrangeop(port1, port2, IPPROTO_SCTP, dir); |
| 5308 | gen_or(tmp, b1); |
| 5309 | break; |
| 5310 | |
| 5311 | default: |
| 5312 | abort(); |
| 5313 | } |
| 5314 | gen_and(b0, b1); |
| 5315 | return b1; |
| 5316 | } |
| 5317 | |
| 5318 | #ifdef INET6 |
| 5319 | static struct block * |
| 5320 | gen_portrangeatom6(off, v1, v2) |
| 5321 | int off; |
| 5322 | bpf_int32 v1, v2; |
| 5323 | { |
| 5324 | struct block *b1, *b2; |
| 5325 | |
| 5326 | if (v1 > v2) { |
| 5327 | /* |
| 5328 | * Reverse the order of the ports, so v1 is the lower one. |
| 5329 | */ |
| 5330 | bpf_int32 vtemp; |
| 5331 | |
| 5332 | vtemp = v1; |
| 5333 | v1 = v2; |
| 5334 | v2 = vtemp; |
| 5335 | } |
| 5336 | |
| 5337 | b1 = gen_cmp_ge(OR_TRAN_IPV6, off, BPF_H, v1); |
| 5338 | b2 = gen_cmp_le(OR_TRAN_IPV6, off, BPF_H, v2); |
| 5339 | |
| 5340 | gen_and(b1, b2); |
| 5341 | |
| 5342 | return b2; |
| 5343 | } |
| 5344 | |
| 5345 | struct block * |
| 5346 | gen_portrangeop6(port1, port2, proto, dir) |
| 5347 | int port1, port2; |
| 5348 | int proto; |
| 5349 | int dir; |
| 5350 | { |
| 5351 | struct block *b0, *b1, *tmp; |
| 5352 | |
| 5353 | /* ip6 proto 'proto' */ |
| 5354 | /* XXX - catch the first fragment of a fragmented packet? */ |
| 5355 | b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto); |
| 5356 | |
| 5357 | switch (dir) { |
| 5358 | case Q_SRC: |
| 5359 | b1 = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2); |
| 5360 | break; |
| 5361 | |
| 5362 | case Q_DST: |
| 5363 | b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2); |
| 5364 | break; |
| 5365 | |
| 5366 | case Q_OR: |
| 5367 | case Q_DEFAULT: |
| 5368 | tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2); |
| 5369 | b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2); |
| 5370 | gen_or(tmp, b1); |
| 5371 | break; |
| 5372 | |
| 5373 | case Q_AND: |
| 5374 | tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2); |
| 5375 | b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2); |
| 5376 | gen_and(tmp, b1); |
| 5377 | break; |
| 5378 | |
| 5379 | default: |
| 5380 | abort(); |
| 5381 | } |
| 5382 | gen_and(b0, b1); |
| 5383 | |
| 5384 | return b1; |
| 5385 | } |
| 5386 | |
| 5387 | static struct block * |
| 5388 | gen_portrange6(port1, port2, ip_proto, dir) |
| 5389 | int port1, port2; |
| 5390 | int ip_proto; |
| 5391 | int dir; |
| 5392 | { |
| 5393 | struct block *b0, *b1, *tmp; |
| 5394 | |
| 5395 | /* link proto ip6 */ |
| 5396 | b0 = gen_linktype(ETHERTYPE_IPV6); |
| 5397 | |
| 5398 | switch (ip_proto) { |
| 5399 | case IPPROTO_UDP: |
| 5400 | case IPPROTO_TCP: |
| 5401 | case IPPROTO_SCTP: |
| 5402 | b1 = gen_portrangeop6(port1, port2, ip_proto, dir); |
| 5403 | break; |
| 5404 | |
| 5405 | case PROTO_UNDEF: |
| 5406 | tmp = gen_portrangeop6(port1, port2, IPPROTO_TCP, dir); |
| 5407 | b1 = gen_portrangeop6(port1, port2, IPPROTO_UDP, dir); |
| 5408 | gen_or(tmp, b1); |
| 5409 | tmp = gen_portrangeop6(port1, port2, IPPROTO_SCTP, dir); |
| 5410 | gen_or(tmp, b1); |
| 5411 | break; |
| 5412 | |
| 5413 | default: |
| 5414 | abort(); |
| 5415 | } |
| 5416 | gen_and(b0, b1); |
| 5417 | return b1; |
| 5418 | } |
| 5419 | #endif /* INET6 */ |
| 5420 | |
| 5421 | static int |
| 5422 | lookup_proto(name, proto) |
| 5423 | register const char *name; |
| 5424 | register int proto; |
| 5425 | { |
| 5426 | register int v; |
| 5427 | |
| 5428 | switch (proto) { |
| 5429 | |
| 5430 | case Q_DEFAULT: |
| 5431 | case Q_IP: |
| 5432 | case Q_IPV6: |
| 5433 | v = pcap_nametoproto(name); |
| 5434 | if (v == PROTO_UNDEF) |
| 5435 | bpf_error("unknown ip proto '%s'", name); |
| 5436 | break; |
| 5437 | |
| 5438 | case Q_LINK: |
| 5439 | /* XXX should look up h/w protocol type based on linktype */ |
| 5440 | v = pcap_nametoeproto(name); |
| 5441 | if (v == PROTO_UNDEF) { |
| 5442 | v = pcap_nametollc(name); |
| 5443 | if (v == PROTO_UNDEF) |
| 5444 | bpf_error("unknown ether proto '%s'", name); |
| 5445 | } |
| 5446 | break; |
| 5447 | |
| 5448 | case Q_ISO: |
| 5449 | if (strcmp(name, "esis") == 0) |
| 5450 | v = ISO9542_ESIS; |
| 5451 | else if (strcmp(name, "isis") == 0) |
| 5452 | v = ISO10589_ISIS; |
| 5453 | else if (strcmp(name, "clnp") == 0) |
| 5454 | v = ISO8473_CLNP; |
| 5455 | else |
| 5456 | bpf_error("unknown osi proto '%s'", name); |
| 5457 | break; |
| 5458 | |
| 5459 | default: |
| 5460 | v = PROTO_UNDEF; |
| 5461 | break; |
| 5462 | } |
| 5463 | return v; |
| 5464 | } |
| 5465 | |
| 5466 | #if 0 |
| 5467 | struct stmt * |
| 5468 | gen_joinsp(s, n) |
| 5469 | struct stmt **s; |
| 5470 | int n; |
| 5471 | { |
| 5472 | return NULL; |
| 5473 | } |
| 5474 | #endif |
| 5475 | |
| 5476 | static struct block * |
| 5477 | gen_protochain(v, proto, dir) |
| 5478 | int v; |
| 5479 | int proto; |
| 5480 | int dir; |
| 5481 | { |
| 5482 | #ifdef NO_PROTOCHAIN |
| 5483 | return gen_proto(v, proto, dir); |
| 5484 | #else |
| 5485 | struct block *b0, *b; |
| 5486 | struct slist *s[100]; |
| 5487 | int fix2, fix3, fix4, fix5; |
| 5488 | int ahcheck, again, end; |
| 5489 | int i, max; |
| 5490 | int reg2 = alloc_reg(); |
| 5491 | |
| 5492 | memset(s, 0, sizeof(s)); |
| 5493 | fix2 = fix3 = fix4 = fix5 = 0; |
| 5494 | |
| 5495 | switch (proto) { |
| 5496 | case Q_IP: |
| 5497 | case Q_IPV6: |
| 5498 | break; |
| 5499 | case Q_DEFAULT: |
| 5500 | b0 = gen_protochain(v, Q_IP, dir); |
| 5501 | b = gen_protochain(v, Q_IPV6, dir); |
| 5502 | gen_or(b0, b); |
| 5503 | return b; |
| 5504 | default: |
| 5505 | bpf_error("bad protocol applied for 'protochain'"); |
| 5506 | /*NOTREACHED*/ |
| 5507 | } |
| 5508 | |
| 5509 | /* |
| 5510 | * We don't handle variable-length prefixes before the link-layer |
| 5511 | * header, or variable-length link-layer headers, here yet. |
| 5512 | * We might want to add BPF instructions to do the protochain |
| 5513 | * work, to simplify that and, on platforms that have a BPF |
| 5514 | * interpreter with the new instructions, let the filtering |
| 5515 | * be done in the kernel. (We already require a modified BPF |
| 5516 | * engine to do the protochain stuff, to support backward |
| 5517 | * branches, and backward branch support is unlikely to appear |
| 5518 | * in kernel BPF engines.) |
| 5519 | */ |
| 5520 | switch (linktype) { |
| 5521 | |
| 5522 | case DLT_IEEE802_11: |
| 5523 | case DLT_PRISM_HEADER: |
| 5524 | case DLT_IEEE802_11_RADIO_AVS: |
| 5525 | case DLT_IEEE802_11_RADIO: |
| 5526 | case DLT_PPI: |
| 5527 | bpf_error("'protochain' not supported with 802.11"); |
| 5528 | } |
| 5529 | |
| 5530 | no_optimize = 1; /*this code is not compatible with optimzer yet */ |
| 5531 | |
| 5532 | /* |
| 5533 | * s[0] is a dummy entry to protect other BPF insn from damage |
| 5534 | * by s[fix] = foo with uninitialized variable "fix". It is somewhat |
| 5535 | * hard to find interdependency made by jump table fixup. |
| 5536 | */ |
| 5537 | i = 0; |
| 5538 | s[i] = new_stmt(0); /*dummy*/ |
| 5539 | i++; |
| 5540 | |
| 5541 | switch (proto) { |
| 5542 | case Q_IP: |
| 5543 | b0 = gen_linktype(ETHERTYPE_IP); |
| 5544 | |
| 5545 | /* A = ip->ip_p */ |
| 5546 | s[i] = new_stmt(BPF_LD|BPF_ABS|BPF_B); |
| 5547 | s[i]->s.k = off_macpl + off_nl + 9; |
| 5548 | i++; |
| 5549 | /* X = ip->ip_hl << 2 */ |
| 5550 | s[i] = new_stmt(BPF_LDX|BPF_MSH|BPF_B); |
| 5551 | s[i]->s.k = off_macpl + off_nl; |
| 5552 | i++; |
| 5553 | break; |
| 5554 | #ifdef INET6 |
| 5555 | case Q_IPV6: |
| 5556 | b0 = gen_linktype(ETHERTYPE_IPV6); |
| 5557 | |
| 5558 | /* A = ip6->ip_nxt */ |
| 5559 | s[i] = new_stmt(BPF_LD|BPF_ABS|BPF_B); |
| 5560 | s[i]->s.k = off_macpl + off_nl + 6; |
| 5561 | i++; |
| 5562 | /* X = sizeof(struct ip6_hdr) */ |
| 5563 | s[i] = new_stmt(BPF_LDX|BPF_IMM); |
| 5564 | s[i]->s.k = 40; |
| 5565 | i++; |
| 5566 | break; |
| 5567 | #endif |
| 5568 | default: |
| 5569 | bpf_error("unsupported proto to gen_protochain"); |
| 5570 | /*NOTREACHED*/ |
| 5571 | } |
| 5572 | |
| 5573 | /* again: if (A == v) goto end; else fall through; */ |
| 5574 | again = i; |
| 5575 | s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K); |
| 5576 | s[i]->s.k = v; |
| 5577 | s[i]->s.jt = NULL; /*later*/ |
| 5578 | s[i]->s.jf = NULL; /*update in next stmt*/ |
| 5579 | fix5 = i; |
| 5580 | i++; |
| 5581 | |
| 5582 | #ifndef IPPROTO_NONE |
| 5583 | #define IPPROTO_NONE 59 |
| 5584 | #endif |
| 5585 | /* if (A == IPPROTO_NONE) goto end */ |
| 5586 | s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K); |
| 5587 | s[i]->s.jt = NULL; /*later*/ |
| 5588 | s[i]->s.jf = NULL; /*update in next stmt*/ |
| 5589 | s[i]->s.k = IPPROTO_NONE; |
| 5590 | s[fix5]->s.jf = s[i]; |
| 5591 | fix2 = i; |
| 5592 | i++; |
| 5593 | |
| 5594 | #ifdef INET6 |
| 5595 | if (proto == Q_IPV6) { |
| 5596 | int v6start, v6end, v6advance, j; |
| 5597 | |
| 5598 | v6start = i; |
| 5599 | /* if (A == IPPROTO_HOPOPTS) goto v6advance */ |
| 5600 | s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K); |
| 5601 | s[i]->s.jt = NULL; /*later*/ |
| 5602 | s[i]->s.jf = NULL; /*update in next stmt*/ |
| 5603 | s[i]->s.k = IPPROTO_HOPOPTS; |
| 5604 | s[fix2]->s.jf = s[i]; |
| 5605 | i++; |
| 5606 | /* if (A == IPPROTO_DSTOPTS) goto v6advance */ |
| 5607 | s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K); |
| 5608 | s[i]->s.jt = NULL; /*later*/ |
| 5609 | s[i]->s.jf = NULL; /*update in next stmt*/ |
| 5610 | s[i]->s.k = IPPROTO_DSTOPTS; |
| 5611 | i++; |
| 5612 | /* if (A == IPPROTO_ROUTING) goto v6advance */ |
| 5613 | s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K); |
| 5614 | s[i]->s.jt = NULL; /*later*/ |
| 5615 | s[i]->s.jf = NULL; /*update in next stmt*/ |
| 5616 | s[i]->s.k = IPPROTO_ROUTING; |
| 5617 | i++; |
| 5618 | /* if (A == IPPROTO_FRAGMENT) goto v6advance; else goto ahcheck; */ |
| 5619 | s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K); |
| 5620 | s[i]->s.jt = NULL; /*later*/ |
| 5621 | s[i]->s.jf = NULL; /*later*/ |
| 5622 | s[i]->s.k = IPPROTO_FRAGMENT; |
| 5623 | fix3 = i; |
| 5624 | v6end = i; |
| 5625 | i++; |
| 5626 | |
| 5627 | /* v6advance: */ |
| 5628 | v6advance = i; |
| 5629 | |
| 5630 | /* |
| 5631 | * in short, |
| 5632 | * A = P[X + packet head]; |
| 5633 | * X = X + (P[X + packet head + 1] + 1) * 8; |
| 5634 | */ |
| 5635 | /* A = P[X + packet head] */ |
| 5636 | s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); |
| 5637 | s[i]->s.k = off_macpl + off_nl; |
| 5638 | i++; |
| 5639 | /* MEM[reg2] = A */ |
| 5640 | s[i] = new_stmt(BPF_ST); |
| 5641 | s[i]->s.k = reg2; |
| 5642 | i++; |
| 5643 | /* A = P[X + packet head + 1]; */ |
| 5644 | s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); |
| 5645 | s[i]->s.k = off_macpl + off_nl + 1; |
| 5646 | i++; |
| 5647 | /* A += 1 */ |
| 5648 | s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); |
| 5649 | s[i]->s.k = 1; |
| 5650 | i++; |
| 5651 | /* A *= 8 */ |
| 5652 | s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K); |
| 5653 | s[i]->s.k = 8; |
| 5654 | i++; |
| 5655 | /* A += X */ |
| 5656 | s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_X); |
| 5657 | s[i]->s.k = 0; |
| 5658 | i++; |
| 5659 | /* X = A; */ |
| 5660 | s[i] = new_stmt(BPF_MISC|BPF_TAX); |
| 5661 | i++; |
| 5662 | /* A = MEM[reg2] */ |
| 5663 | s[i] = new_stmt(BPF_LD|BPF_MEM); |
| 5664 | s[i]->s.k = reg2; |
| 5665 | i++; |
| 5666 | |
| 5667 | /* goto again; (must use BPF_JA for backward jump) */ |
| 5668 | s[i] = new_stmt(BPF_JMP|BPF_JA); |
| 5669 | s[i]->s.k = again - i - 1; |
| 5670 | s[i - 1]->s.jf = s[i]; |
| 5671 | i++; |
| 5672 | |
| 5673 | /* fixup */ |
| 5674 | for (j = v6start; j <= v6end; j++) |
| 5675 | s[j]->s.jt = s[v6advance]; |
| 5676 | } else |
| 5677 | #endif |
| 5678 | { |
| 5679 | /* nop */ |
| 5680 | s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); |
| 5681 | s[i]->s.k = 0; |
| 5682 | s[fix2]->s.jf = s[i]; |
| 5683 | i++; |
| 5684 | } |
| 5685 | |
| 5686 | /* ahcheck: */ |
| 5687 | ahcheck = i; |
| 5688 | /* if (A == IPPROTO_AH) then fall through; else goto end; */ |
| 5689 | s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K); |
| 5690 | s[i]->s.jt = NULL; /*later*/ |
| 5691 | s[i]->s.jf = NULL; /*later*/ |
| 5692 | s[i]->s.k = IPPROTO_AH; |
| 5693 | if (fix3) |
| 5694 | s[fix3]->s.jf = s[ahcheck]; |
| 5695 | fix4 = i; |
| 5696 | i++; |
| 5697 | |
| 5698 | /* |
| 5699 | * in short, |
| 5700 | * A = P[X]; |
| 5701 | * X = X + (P[X + 1] + 2) * 4; |
| 5702 | */ |
| 5703 | /* A = X */ |
| 5704 | s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA); |
| 5705 | i++; |
| 5706 | /* A = P[X + packet head]; */ |
| 5707 | s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); |
| 5708 | s[i]->s.k = off_macpl + off_nl; |
| 5709 | i++; |
| 5710 | /* MEM[reg2] = A */ |
| 5711 | s[i] = new_stmt(BPF_ST); |
| 5712 | s[i]->s.k = reg2; |
| 5713 | i++; |
| 5714 | /* A = X */ |
| 5715 | s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA); |
| 5716 | i++; |
| 5717 | /* A += 1 */ |
| 5718 | s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); |
| 5719 | s[i]->s.k = 1; |
| 5720 | i++; |
| 5721 | /* X = A */ |
| 5722 | s[i] = new_stmt(BPF_MISC|BPF_TAX); |
| 5723 | i++; |
| 5724 | /* A = P[X + packet head] */ |
| 5725 | s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B); |
| 5726 | s[i]->s.k = off_macpl + off_nl; |
| 5727 | i++; |
| 5728 | /* A += 2 */ |
| 5729 | s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); |
| 5730 | s[i]->s.k = 2; |
| 5731 | i++; |
| 5732 | /* A *= 4 */ |
| 5733 | s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K); |
| 5734 | s[i]->s.k = 4; |
| 5735 | i++; |
| 5736 | /* X = A; */ |
| 5737 | s[i] = new_stmt(BPF_MISC|BPF_TAX); |
| 5738 | i++; |
| 5739 | /* A = MEM[reg2] */ |
| 5740 | s[i] = new_stmt(BPF_LD|BPF_MEM); |
| 5741 | s[i]->s.k = reg2; |
| 5742 | i++; |
| 5743 | |
| 5744 | /* goto again; (must use BPF_JA for backward jump) */ |
| 5745 | s[i] = new_stmt(BPF_JMP|BPF_JA); |
| 5746 | s[i]->s.k = again - i - 1; |
| 5747 | i++; |
| 5748 | |
| 5749 | /* end: nop */ |
| 5750 | end = i; |
| 5751 | s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K); |
| 5752 | s[i]->s.k = 0; |
| 5753 | s[fix2]->s.jt = s[end]; |
| 5754 | s[fix4]->s.jf = s[end]; |
| 5755 | s[fix5]->s.jt = s[end]; |
| 5756 | i++; |
| 5757 | |
| 5758 | /* |
| 5759 | * make slist chain |
| 5760 | */ |
| 5761 | max = i; |
| 5762 | for (i = 0; i < max - 1; i++) |
| 5763 | s[i]->next = s[i + 1]; |
| 5764 | s[max - 1]->next = NULL; |
| 5765 | |
| 5766 | /* |
| 5767 | * emit final check |
| 5768 | */ |
| 5769 | b = new_block(JMP(BPF_JEQ)); |
| 5770 | b->stmts = s[1]; /*remember, s[0] is dummy*/ |
| 5771 | b->s.k = v; |
| 5772 | |
| 5773 | free_reg(reg2); |
| 5774 | |
| 5775 | gen_and(b0, b); |
| 5776 | return b; |
| 5777 | #endif |
| 5778 | } |
| 5779 | |
| 5780 | static struct block * |
| 5781 | gen_check_802_11_data_frame() |
| 5782 | { |
| 5783 | struct slist *s; |
| 5784 | struct block *b0, *b1; |
| 5785 | |
| 5786 | /* |
| 5787 | * A data frame has the 0x08 bit (b3) in the frame control field set |
| 5788 | * and the 0x04 bit (b2) clear. |
| 5789 | */ |
| 5790 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 5791 | b0 = new_block(JMP(BPF_JSET)); |
| 5792 | b0->s.k = 0x08; |
| 5793 | b0->stmts = s; |
| 5794 | |
| 5795 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 5796 | b1 = new_block(JMP(BPF_JSET)); |
| 5797 | b1->s.k = 0x04; |
| 5798 | b1->stmts = s; |
| 5799 | gen_not(b1); |
| 5800 | |
| 5801 | gen_and(b1, b0); |
| 5802 | |
| 5803 | return b0; |
| 5804 | } |
| 5805 | |
| 5806 | /* |
| 5807 | * Generate code that checks whether the packet is a packet for protocol |
| 5808 | * <proto> and whether the type field in that protocol's header has |
| 5809 | * the value <v>, e.g. if <proto> is Q_IP, it checks whether it's an |
| 5810 | * IP packet and checks the protocol number in the IP header against <v>. |
| 5811 | * |
| 5812 | * If <proto> is Q_DEFAULT, i.e. just "proto" was specified, it checks |
| 5813 | * against Q_IP and Q_IPV6. |
| 5814 | */ |
| 5815 | static struct block * |
| 5816 | gen_proto(v, proto, dir) |
| 5817 | int v; |
| 5818 | int proto; |
| 5819 | int dir; |
| 5820 | { |
| 5821 | struct block *b0, *b1; |
| 5822 | |
| 5823 | if (dir != Q_DEFAULT) |
| 5824 | bpf_error("direction applied to 'proto'"); |
| 5825 | |
| 5826 | switch (proto) { |
| 5827 | case Q_DEFAULT: |
| 5828 | #ifdef INET6 |
| 5829 | b0 = gen_proto(v, Q_IP, dir); |
| 5830 | b1 = gen_proto(v, Q_IPV6, dir); |
| 5831 | gen_or(b0, b1); |
| 5832 | return b1; |
| 5833 | #else |
| 5834 | /*FALLTHROUGH*/ |
| 5835 | #endif |
| 5836 | case Q_IP: |
| 5837 | /* |
| 5838 | * For FDDI, RFC 1188 says that SNAP encapsulation is used, |
| 5839 | * not LLC encapsulation with LLCSAP_IP. |
| 5840 | * |
| 5841 | * For IEEE 802 networks - which includes 802.5 token ring |
| 5842 | * (which is what DLT_IEEE802 means) and 802.11 - RFC 1042 |
| 5843 | * says that SNAP encapsulation is used, not LLC encapsulation |
| 5844 | * with LLCSAP_IP. |
| 5845 | * |
| 5846 | * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and |
| 5847 | * RFC 2225 say that SNAP encapsulation is used, not LLC |
| 5848 | * encapsulation with LLCSAP_IP. |
| 5849 | * |
| 5850 | * So we always check for ETHERTYPE_IP. |
| 5851 | */ |
| 5852 | b0 = gen_linktype(ETHERTYPE_IP); |
| 5853 | #ifndef CHASE_CHAIN |
| 5854 | b1 = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)v); |
| 5855 | #else |
| 5856 | b1 = gen_protochain(v, Q_IP); |
| 5857 | #endif |
| 5858 | gen_and(b0, b1); |
| 5859 | return b1; |
| 5860 | |
| 5861 | case Q_ISO: |
| 5862 | switch (linktype) { |
| 5863 | |
| 5864 | case DLT_FRELAY: |
| 5865 | /* |
| 5866 | * Frame Relay packets typically have an OSI |
| 5867 | * NLPID at the beginning; "gen_linktype(LLCSAP_ISONS)" |
| 5868 | * generates code to check for all the OSI |
| 5869 | * NLPIDs, so calling it and then adding a check |
| 5870 | * for the particular NLPID for which we're |
| 5871 | * looking is bogus, as we can just check for |
| 5872 | * the NLPID. |
| 5873 | * |
| 5874 | * What we check for is the NLPID and a frame |
| 5875 | * control field value of UI, i.e. 0x03 followed |
| 5876 | * by the NLPID. |
| 5877 | * |
| 5878 | * XXX - assumes a 2-byte Frame Relay header with |
| 5879 | * DLCI and flags. What if the address is longer? |
| 5880 | * |
| 5881 | * XXX - what about SNAP-encapsulated frames? |
| 5882 | */ |
| 5883 | return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | v); |
| 5884 | /*NOTREACHED*/ |
| 5885 | break; |
| 5886 | |
| 5887 | case DLT_C_HDLC: |
| 5888 | /* |
| 5889 | * Cisco uses an Ethertype lookalike - for OSI, |
| 5890 | * it's 0xfefe. |
| 5891 | */ |
| 5892 | b0 = gen_linktype(LLCSAP_ISONS<<8 | LLCSAP_ISONS); |
| 5893 | /* OSI in C-HDLC is stuffed with a fudge byte */ |
| 5894 | b1 = gen_cmp(OR_NET_NOSNAP, 1, BPF_B, (long)v); |
| 5895 | gen_and(b0, b1); |
| 5896 | return b1; |
| 5897 | |
| 5898 | default: |
| 5899 | b0 = gen_linktype(LLCSAP_ISONS); |
| 5900 | b1 = gen_cmp(OR_NET_NOSNAP, 0, BPF_B, (long)v); |
| 5901 | gen_and(b0, b1); |
| 5902 | return b1; |
| 5903 | } |
| 5904 | |
| 5905 | case Q_ISIS: |
| 5906 | b0 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT); |
| 5907 | /* |
| 5908 | * 4 is the offset of the PDU type relative to the IS-IS |
| 5909 | * header. |
| 5910 | */ |
| 5911 | b1 = gen_cmp(OR_NET_NOSNAP, 4, BPF_B, (long)v); |
| 5912 | gen_and(b0, b1); |
| 5913 | return b1; |
| 5914 | |
| 5915 | case Q_ARP: |
| 5916 | bpf_error("arp does not encapsulate another protocol"); |
| 5917 | /* NOTREACHED */ |
| 5918 | |
| 5919 | case Q_RARP: |
| 5920 | bpf_error("rarp does not encapsulate another protocol"); |
| 5921 | /* NOTREACHED */ |
| 5922 | |
| 5923 | case Q_ATALK: |
| 5924 | bpf_error("atalk encapsulation is not specifiable"); |
| 5925 | /* NOTREACHED */ |
| 5926 | |
| 5927 | case Q_DECNET: |
| 5928 | bpf_error("decnet encapsulation is not specifiable"); |
| 5929 | /* NOTREACHED */ |
| 5930 | |
| 5931 | case Q_SCA: |
| 5932 | bpf_error("sca does not encapsulate another protocol"); |
| 5933 | /* NOTREACHED */ |
| 5934 | |
| 5935 | case Q_LAT: |
| 5936 | bpf_error("lat does not encapsulate another protocol"); |
| 5937 | /* NOTREACHED */ |
| 5938 | |
| 5939 | case Q_MOPRC: |
| 5940 | bpf_error("moprc does not encapsulate another protocol"); |
| 5941 | /* NOTREACHED */ |
| 5942 | |
| 5943 | case Q_MOPDL: |
| 5944 | bpf_error("mopdl does not encapsulate another protocol"); |
| 5945 | /* NOTREACHED */ |
| 5946 | |
| 5947 | case Q_LINK: |
| 5948 | return gen_linktype(v); |
| 5949 | |
| 5950 | case Q_UDP: |
| 5951 | bpf_error("'udp proto' is bogus"); |
| 5952 | /* NOTREACHED */ |
| 5953 | |
| 5954 | case Q_TCP: |
| 5955 | bpf_error("'tcp proto' is bogus"); |
| 5956 | /* NOTREACHED */ |
| 5957 | |
| 5958 | case Q_SCTP: |
| 5959 | bpf_error("'sctp proto' is bogus"); |
| 5960 | /* NOTREACHED */ |
| 5961 | |
| 5962 | case Q_ICMP: |
| 5963 | bpf_error("'icmp proto' is bogus"); |
| 5964 | /* NOTREACHED */ |
| 5965 | |
| 5966 | case Q_IGMP: |
| 5967 | bpf_error("'igmp proto' is bogus"); |
| 5968 | /* NOTREACHED */ |
| 5969 | |
| 5970 | case Q_IGRP: |
| 5971 | bpf_error("'igrp proto' is bogus"); |
| 5972 | /* NOTREACHED */ |
| 5973 | |
| 5974 | case Q_PIM: |
| 5975 | bpf_error("'pim proto' is bogus"); |
| 5976 | /* NOTREACHED */ |
| 5977 | |
| 5978 | case Q_VRRP: |
| 5979 | bpf_error("'vrrp proto' is bogus"); |
| 5980 | /* NOTREACHED */ |
| 5981 | |
| 5982 | case Q_CARP: |
| 5983 | bpf_error("'carp proto' is bogus"); |
| 5984 | /* NOTREACHED */ |
| 5985 | |
| 5986 | #ifdef INET6 |
| 5987 | case Q_IPV6: |
| 5988 | b0 = gen_linktype(ETHERTYPE_IPV6); |
| 5989 | #ifndef CHASE_CHAIN |
| 5990 | b1 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)v); |
| 5991 | #else |
| 5992 | b1 = gen_protochain(v, Q_IPV6); |
| 5993 | #endif |
| 5994 | gen_and(b0, b1); |
| 5995 | return b1; |
| 5996 | |
| 5997 | case Q_ICMPV6: |
| 5998 | bpf_error("'icmp6 proto' is bogus"); |
| 5999 | #endif /* INET6 */ |
| 6000 | |
| 6001 | case Q_AH: |
| 6002 | bpf_error("'ah proto' is bogus"); |
| 6003 | |
| 6004 | case Q_ESP: |
| 6005 | bpf_error("'ah proto' is bogus"); |
| 6006 | |
| 6007 | case Q_STP: |
| 6008 | bpf_error("'stp proto' is bogus"); |
| 6009 | |
| 6010 | case Q_IPX: |
| 6011 | bpf_error("'ipx proto' is bogus"); |
| 6012 | |
| 6013 | case Q_NETBEUI: |
| 6014 | bpf_error("'netbeui proto' is bogus"); |
| 6015 | |
| 6016 | case Q_RADIO: |
| 6017 | bpf_error("'radio proto' is bogus"); |
| 6018 | |
| 6019 | default: |
| 6020 | abort(); |
| 6021 | /* NOTREACHED */ |
| 6022 | } |
| 6023 | /* NOTREACHED */ |
| 6024 | } |
| 6025 | |
| 6026 | struct block * |
| 6027 | gen_scode(name, q) |
| 6028 | register const char *name; |
| 6029 | struct qual q; |
| 6030 | { |
| 6031 | int proto = q.proto; |
| 6032 | int dir = q.dir; |
| 6033 | int tproto; |
| 6034 | u_char *eaddr; |
| 6035 | bpf_u_int32 mask, addr; |
| 6036 | #ifndef INET6 |
| 6037 | bpf_u_int32 **alist; |
| 6038 | #else |
| 6039 | int tproto6; |
| 6040 | struct sockaddr_in *sin4; |
| 6041 | struct sockaddr_in6 *sin6; |
| 6042 | struct addrinfo *res, *res0; |
| 6043 | struct in6_addr mask128; |
| 6044 | #endif /*INET6*/ |
| 6045 | struct block *b, *tmp; |
| 6046 | int port, real_proto; |
| 6047 | int port1, port2; |
| 6048 | |
| 6049 | switch (q.addr) { |
| 6050 | |
| 6051 | case Q_NET: |
| 6052 | addr = pcap_nametonetaddr(name); |
| 6053 | if (addr == 0) |
| 6054 | bpf_error("unknown network '%s'", name); |
| 6055 | /* Left justify network addr and calculate its network mask */ |
| 6056 | mask = 0xffffffff; |
| 6057 | while (addr && (addr & 0xff000000) == 0) { |
| 6058 | addr <<= 8; |
| 6059 | mask <<= 8; |
| 6060 | } |
| 6061 | return gen_host(addr, mask, proto, dir, q.addr); |
| 6062 | |
| 6063 | case Q_DEFAULT: |
| 6064 | case Q_HOST: |
| 6065 | if (proto == Q_LINK) { |
| 6066 | switch (linktype) { |
| 6067 | |
| 6068 | case DLT_EN10MB: |
| 6069 | case DLT_NETANALYZER: |
| 6070 | case DLT_NETANALYZER_TRANSPARENT: |
| 6071 | eaddr = pcap_ether_hostton(name); |
| 6072 | if (eaddr == NULL) |
| 6073 | bpf_error( |
| 6074 | "unknown ether host '%s'", name); |
| 6075 | b = gen_ehostop(eaddr, dir); |
| 6076 | free(eaddr); |
| 6077 | return b; |
| 6078 | |
| 6079 | case DLT_FDDI: |
| 6080 | eaddr = pcap_ether_hostton(name); |
| 6081 | if (eaddr == NULL) |
| 6082 | bpf_error( |
| 6083 | "unknown FDDI host '%s'", name); |
| 6084 | b = gen_fhostop(eaddr, dir); |
| 6085 | free(eaddr); |
| 6086 | return b; |
| 6087 | |
| 6088 | case DLT_IEEE802: |
| 6089 | eaddr = pcap_ether_hostton(name); |
| 6090 | if (eaddr == NULL) |
| 6091 | bpf_error( |
| 6092 | "unknown token ring host '%s'", name); |
| 6093 | b = gen_thostop(eaddr, dir); |
| 6094 | free(eaddr); |
| 6095 | return b; |
| 6096 | |
| 6097 | case DLT_IEEE802_11: |
| 6098 | case DLT_PRISM_HEADER: |
| 6099 | case DLT_IEEE802_11_RADIO_AVS: |
| 6100 | case DLT_IEEE802_11_RADIO: |
| 6101 | case DLT_PPI: |
| 6102 | eaddr = pcap_ether_hostton(name); |
| 6103 | if (eaddr == NULL) |
| 6104 | bpf_error( |
| 6105 | "unknown 802.11 host '%s'", name); |
| 6106 | b = gen_wlanhostop(eaddr, dir); |
| 6107 | free(eaddr); |
| 6108 | return b; |
| 6109 | |
| 6110 | case DLT_IP_OVER_FC: |
| 6111 | eaddr = pcap_ether_hostton(name); |
| 6112 | if (eaddr == NULL) |
| 6113 | bpf_error( |
| 6114 | "unknown Fibre Channel host '%s'", name); |
| 6115 | b = gen_ipfchostop(eaddr, dir); |
| 6116 | free(eaddr); |
| 6117 | return b; |
| 6118 | |
| 6119 | case DLT_SUNATM: |
| 6120 | if (!is_lane) |
| 6121 | break; |
| 6122 | |
| 6123 | /* |
| 6124 | * Check that the packet doesn't begin |
| 6125 | * with an LE Control marker. (We've |
| 6126 | * already generated a test for LANE.) |
| 6127 | */ |
| 6128 | tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, |
| 6129 | BPF_H, 0xFF00); |
| 6130 | gen_not(tmp); |
| 6131 | |
| 6132 | eaddr = pcap_ether_hostton(name); |
| 6133 | if (eaddr == NULL) |
| 6134 | bpf_error( |
| 6135 | "unknown ether host '%s'", name); |
| 6136 | b = gen_ehostop(eaddr, dir); |
| 6137 | gen_and(tmp, b); |
| 6138 | free(eaddr); |
| 6139 | return b; |
| 6140 | } |
| 6141 | |
| 6142 | bpf_error("only ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel supports link-level host name"); |
| 6143 | } else if (proto == Q_DECNET) { |
| 6144 | unsigned short dn_addr = __pcap_nametodnaddr(name); |
| 6145 | /* |
| 6146 | * I don't think DECNET hosts can be multihomed, so |
| 6147 | * there is no need to build up a list of addresses |
| 6148 | */ |
| 6149 | return (gen_host(dn_addr, 0, proto, dir, q.addr)); |
| 6150 | } else { |
| 6151 | #ifndef INET6 |
| 6152 | alist = pcap_nametoaddr(name); |
| 6153 | if (alist == NULL || *alist == NULL) |
| 6154 | bpf_error("unknown host '%s'", name); |
| 6155 | tproto = proto; |
| 6156 | if (off_linktype == (u_int)-1 && tproto == Q_DEFAULT) |
| 6157 | tproto = Q_IP; |
| 6158 | b = gen_host(**alist++, 0xffffffff, tproto, dir, q.addr); |
| 6159 | while (*alist) { |
| 6160 | tmp = gen_host(**alist++, 0xffffffff, |
| 6161 | tproto, dir, q.addr); |
| 6162 | gen_or(b, tmp); |
| 6163 | b = tmp; |
| 6164 | } |
| 6165 | return b; |
| 6166 | #else |
| 6167 | memset(&mask128, 0xff, sizeof(mask128)); |
| 6168 | res0 = res = pcap_nametoaddrinfo(name); |
| 6169 | if (res == NULL) |
| 6170 | bpf_error("unknown host '%s'", name); |
| 6171 | ai = res; |
| 6172 | b = tmp = NULL; |
| 6173 | tproto = tproto6 = proto; |
| 6174 | if (off_linktype == -1 && tproto == Q_DEFAULT) { |
| 6175 | tproto = Q_IP; |
| 6176 | tproto6 = Q_IPV6; |
| 6177 | } |
| 6178 | for (res = res0; res; res = res->ai_next) { |
| 6179 | switch (res->ai_family) { |
| 6180 | case AF_INET: |
| 6181 | if (tproto == Q_IPV6) |
| 6182 | continue; |
| 6183 | |
| 6184 | sin4 = (struct sockaddr_in *) |
| 6185 | res->ai_addr; |
| 6186 | tmp = gen_host(ntohl(sin4->sin_addr.s_addr), |
| 6187 | 0xffffffff, tproto, dir, q.addr); |
| 6188 | break; |
| 6189 | case AF_INET6: |
| 6190 | if (tproto6 == Q_IP) |
| 6191 | continue; |
| 6192 | |
| 6193 | sin6 = (struct sockaddr_in6 *) |
| 6194 | res->ai_addr; |
| 6195 | tmp = gen_host6(&sin6->sin6_addr, |
| 6196 | &mask128, tproto6, dir, q.addr); |
| 6197 | break; |
| 6198 | default: |
| 6199 | continue; |
| 6200 | } |
| 6201 | if (b) |
| 6202 | gen_or(b, tmp); |
| 6203 | b = tmp; |
| 6204 | } |
| 6205 | ai = NULL; |
| 6206 | freeaddrinfo(res0); |
| 6207 | if (b == NULL) { |
| 6208 | bpf_error("unknown host '%s'%s", name, |
| 6209 | (proto == Q_DEFAULT) |
| 6210 | ? "" |
| 6211 | : " for specified address family"); |
| 6212 | } |
| 6213 | return b; |
| 6214 | #endif /*INET6*/ |
| 6215 | } |
| 6216 | |
| 6217 | case Q_PORT: |
| 6218 | if (proto != Q_DEFAULT && |
| 6219 | proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP) |
| 6220 | bpf_error("illegal qualifier of 'port'"); |
| 6221 | if (pcap_nametoport(name, &port, &real_proto) == 0) |
| 6222 | bpf_error("unknown port '%s'", name); |
| 6223 | if (proto == Q_UDP) { |
| 6224 | if (real_proto == IPPROTO_TCP) |
| 6225 | bpf_error("port '%s' is tcp", name); |
| 6226 | else if (real_proto == IPPROTO_SCTP) |
| 6227 | bpf_error("port '%s' is sctp", name); |
| 6228 | else |
| 6229 | /* override PROTO_UNDEF */ |
| 6230 | real_proto = IPPROTO_UDP; |
| 6231 | } |
| 6232 | if (proto == Q_TCP) { |
| 6233 | if (real_proto == IPPROTO_UDP) |
| 6234 | bpf_error("port '%s' is udp", name); |
| 6235 | |
| 6236 | else if (real_proto == IPPROTO_SCTP) |
| 6237 | bpf_error("port '%s' is sctp", name); |
| 6238 | else |
| 6239 | /* override PROTO_UNDEF */ |
| 6240 | real_proto = IPPROTO_TCP; |
| 6241 | } |
| 6242 | if (proto == Q_SCTP) { |
| 6243 | if (real_proto == IPPROTO_UDP) |
| 6244 | bpf_error("port '%s' is udp", name); |
| 6245 | |
| 6246 | else if (real_proto == IPPROTO_TCP) |
| 6247 | bpf_error("port '%s' is tcp", name); |
| 6248 | else |
| 6249 | /* override PROTO_UNDEF */ |
| 6250 | real_proto = IPPROTO_SCTP; |
| 6251 | } |
| 6252 | if (port < 0) |
| 6253 | bpf_error("illegal port number %d < 0", port); |
| 6254 | if (port > 65535) |
| 6255 | bpf_error("illegal port number %d > 65535", port); |
| 6256 | #ifndef INET6 |
| 6257 | return gen_port(port, real_proto, dir); |
| 6258 | #else |
| 6259 | b = gen_port(port, real_proto, dir); |
| 6260 | gen_or(gen_port6(port, real_proto, dir), b); |
| 6261 | return b; |
| 6262 | #endif /* INET6 */ |
| 6263 | |
| 6264 | case Q_PORTRANGE: |
| 6265 | if (proto != Q_DEFAULT && |
| 6266 | proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP) |
| 6267 | bpf_error("illegal qualifier of 'portrange'"); |
| 6268 | if (pcap_nametoportrange(name, &port1, &port2, &real_proto) == 0) |
| 6269 | bpf_error("unknown port in range '%s'", name); |
| 6270 | if (proto == Q_UDP) { |
| 6271 | if (real_proto == IPPROTO_TCP) |
| 6272 | bpf_error("port in range '%s' is tcp", name); |
| 6273 | else if (real_proto == IPPROTO_SCTP) |
| 6274 | bpf_error("port in range '%s' is sctp", name); |
| 6275 | else |
| 6276 | /* override PROTO_UNDEF */ |
| 6277 | real_proto = IPPROTO_UDP; |
| 6278 | } |
| 6279 | if (proto == Q_TCP) { |
| 6280 | if (real_proto == IPPROTO_UDP) |
| 6281 | bpf_error("port in range '%s' is udp", name); |
| 6282 | else if (real_proto == IPPROTO_SCTP) |
| 6283 | bpf_error("port in range '%s' is sctp", name); |
| 6284 | else |
| 6285 | /* override PROTO_UNDEF */ |
| 6286 | real_proto = IPPROTO_TCP; |
| 6287 | } |
| 6288 | if (proto == Q_SCTP) { |
| 6289 | if (real_proto == IPPROTO_UDP) |
| 6290 | bpf_error("port in range '%s' is udp", name); |
| 6291 | else if (real_proto == IPPROTO_TCP) |
| 6292 | bpf_error("port in range '%s' is tcp", name); |
| 6293 | else |
| 6294 | /* override PROTO_UNDEF */ |
| 6295 | real_proto = IPPROTO_SCTP; |
| 6296 | } |
| 6297 | if (port1 < 0) |
| 6298 | bpf_error("illegal port number %d < 0", port1); |
| 6299 | if (port1 > 65535) |
| 6300 | bpf_error("illegal port number %d > 65535", port1); |
| 6301 | if (port2 < 0) |
| 6302 | bpf_error("illegal port number %d < 0", port2); |
| 6303 | if (port2 > 65535) |
| 6304 | bpf_error("illegal port number %d > 65535", port2); |
| 6305 | |
| 6306 | #ifndef INET6 |
| 6307 | return gen_portrange(port1, port2, real_proto, dir); |
| 6308 | #else |
| 6309 | b = gen_portrange(port1, port2, real_proto, dir); |
| 6310 | gen_or(gen_portrange6(port1, port2, real_proto, dir), b); |
| 6311 | return b; |
| 6312 | #endif /* INET6 */ |
| 6313 | |
| 6314 | case Q_GATEWAY: |
| 6315 | #ifndef INET6 |
| 6316 | eaddr = pcap_ether_hostton(name); |
| 6317 | if (eaddr == NULL) |
| 6318 | bpf_error("unknown ether host: %s", name); |
| 6319 | |
| 6320 | alist = pcap_nametoaddr(name); |
| 6321 | if (alist == NULL || *alist == NULL) |
| 6322 | bpf_error("unknown host '%s'", name); |
| 6323 | b = gen_gateway(eaddr, alist, proto, dir); |
| 6324 | free(eaddr); |
| 6325 | return b; |
| 6326 | #else |
| 6327 | bpf_error("'gateway' not supported in this configuration"); |
| 6328 | #endif /*INET6*/ |
| 6329 | |
| 6330 | case Q_PROTO: |
| 6331 | real_proto = lookup_proto(name, proto); |
| 6332 | if (real_proto >= 0) |
| 6333 | return gen_proto(real_proto, proto, dir); |
| 6334 | else |
| 6335 | bpf_error("unknown protocol: %s", name); |
| 6336 | |
| 6337 | case Q_PROTOCHAIN: |
| 6338 | real_proto = lookup_proto(name, proto); |
| 6339 | if (real_proto >= 0) |
| 6340 | return gen_protochain(real_proto, proto, dir); |
| 6341 | else |
| 6342 | bpf_error("unknown protocol: %s", name); |
| 6343 | |
| 6344 | case Q_UNDEF: |
| 6345 | syntax(); |
| 6346 | /* NOTREACHED */ |
| 6347 | } |
| 6348 | abort(); |
| 6349 | /* NOTREACHED */ |
| 6350 | } |
| 6351 | |
| 6352 | struct block * |
| 6353 | gen_mcode(s1, s2, masklen, q) |
| 6354 | register const char *s1, *s2; |
| 6355 | register int masklen; |
| 6356 | struct qual q; |
| 6357 | { |
| 6358 | register int nlen, mlen; |
| 6359 | bpf_u_int32 n, m; |
| 6360 | |
| 6361 | nlen = __pcap_atoin(s1, &n); |
| 6362 | /* Promote short ipaddr */ |
| 6363 | n <<= 32 - nlen; |
| 6364 | |
| 6365 | if (s2 != NULL) { |
| 6366 | mlen = __pcap_atoin(s2, &m); |
| 6367 | /* Promote short ipaddr */ |
| 6368 | m <<= 32 - mlen; |
| 6369 | if ((n & ~m) != 0) |
| 6370 | bpf_error("non-network bits set in \"%s mask %s\"", |
| 6371 | s1, s2); |
| 6372 | } else { |
| 6373 | /* Convert mask len to mask */ |
| 6374 | if (masklen > 32) |
| 6375 | bpf_error("mask length must be <= 32"); |
| 6376 | if (masklen == 0) { |
| 6377 | /* |
| 6378 | * X << 32 is not guaranteed by C to be 0; it's |
| 6379 | * undefined. |
| 6380 | */ |
| 6381 | m = 0; |
| 6382 | } else |
| 6383 | m = 0xffffffff << (32 - masklen); |
| 6384 | if ((n & ~m) != 0) |
| 6385 | bpf_error("non-network bits set in \"%s/%d\"", |
| 6386 | s1, masklen); |
| 6387 | } |
| 6388 | |
| 6389 | switch (q.addr) { |
| 6390 | |
| 6391 | case Q_NET: |
| 6392 | return gen_host(n, m, q.proto, q.dir, q.addr); |
| 6393 | |
| 6394 | default: |
| 6395 | bpf_error("Mask syntax for networks only"); |
| 6396 | /* NOTREACHED */ |
| 6397 | } |
| 6398 | /* NOTREACHED */ |
| 6399 | return NULL; |
| 6400 | } |
| 6401 | |
| 6402 | struct block * |
| 6403 | gen_ncode(s, v, q) |
| 6404 | register const char *s; |
| 6405 | bpf_u_int32 v; |
| 6406 | struct qual q; |
| 6407 | { |
| 6408 | bpf_u_int32 mask; |
| 6409 | int proto = q.proto; |
| 6410 | int dir = q.dir; |
| 6411 | register int vlen; |
| 6412 | |
| 6413 | if (s == NULL) |
| 6414 | vlen = 32; |
| 6415 | else if (q.proto == Q_DECNET) |
| 6416 | vlen = __pcap_atodn(s, &v); |
| 6417 | else |
| 6418 | vlen = __pcap_atoin(s, &v); |
| 6419 | |
| 6420 | switch (q.addr) { |
| 6421 | |
| 6422 | case Q_DEFAULT: |
| 6423 | case Q_HOST: |
| 6424 | case Q_NET: |
| 6425 | if (proto == Q_DECNET) |
| 6426 | return gen_host(v, 0, proto, dir, q.addr); |
| 6427 | else if (proto == Q_LINK) { |
| 6428 | bpf_error("illegal link layer address"); |
| 6429 | } else { |
| 6430 | mask = 0xffffffff; |
| 6431 | if (s == NULL && q.addr == Q_NET) { |
| 6432 | /* Promote short net number */ |
| 6433 | while (v && (v & 0xff000000) == 0) { |
| 6434 | v <<= 8; |
| 6435 | mask <<= 8; |
| 6436 | } |
| 6437 | } else { |
| 6438 | /* Promote short ipaddr */ |
| 6439 | v <<= 32 - vlen; |
| 6440 | mask <<= 32 - vlen; |
| 6441 | } |
| 6442 | return gen_host(v, mask, proto, dir, q.addr); |
| 6443 | } |
| 6444 | |
| 6445 | case Q_PORT: |
| 6446 | if (proto == Q_UDP) |
| 6447 | proto = IPPROTO_UDP; |
| 6448 | else if (proto == Q_TCP) |
| 6449 | proto = IPPROTO_TCP; |
| 6450 | else if (proto == Q_SCTP) |
| 6451 | proto = IPPROTO_SCTP; |
| 6452 | else if (proto == Q_DEFAULT) |
| 6453 | proto = PROTO_UNDEF; |
| 6454 | else |
| 6455 | bpf_error("illegal qualifier of 'port'"); |
| 6456 | |
| 6457 | if (v > 65535) |
| 6458 | bpf_error("illegal port number %u > 65535", v); |
| 6459 | |
| 6460 | #ifndef INET6 |
| 6461 | return gen_port((int)v, proto, dir); |
| 6462 | #else |
| 6463 | { |
| 6464 | struct block *b; |
| 6465 | b = gen_port((int)v, proto, dir); |
| 6466 | gen_or(gen_port6((int)v, proto, dir), b); |
| 6467 | return b; |
| 6468 | } |
| 6469 | #endif /* INET6 */ |
| 6470 | |
| 6471 | case Q_PORTRANGE: |
| 6472 | if (proto == Q_UDP) |
| 6473 | proto = IPPROTO_UDP; |
| 6474 | else if (proto == Q_TCP) |
| 6475 | proto = IPPROTO_TCP; |
| 6476 | else if (proto == Q_SCTP) |
| 6477 | proto = IPPROTO_SCTP; |
| 6478 | else if (proto == Q_DEFAULT) |
| 6479 | proto = PROTO_UNDEF; |
| 6480 | else |
| 6481 | bpf_error("illegal qualifier of 'portrange'"); |
| 6482 | |
| 6483 | if (v > 65535) |
| 6484 | bpf_error("illegal port number %u > 65535", v); |
| 6485 | |
| 6486 | #ifndef INET6 |
| 6487 | return gen_portrange((int)v, (int)v, proto, dir); |
| 6488 | #else |
| 6489 | { |
| 6490 | struct block *b; |
| 6491 | b = gen_portrange((int)v, (int)v, proto, dir); |
| 6492 | gen_or(gen_portrange6((int)v, (int)v, proto, dir), b); |
| 6493 | return b; |
| 6494 | } |
| 6495 | #endif /* INET6 */ |
| 6496 | |
| 6497 | case Q_GATEWAY: |
| 6498 | bpf_error("'gateway' requires a name"); |
| 6499 | /* NOTREACHED */ |
| 6500 | |
| 6501 | case Q_PROTO: |
| 6502 | return gen_proto((int)v, proto, dir); |
| 6503 | |
| 6504 | case Q_PROTOCHAIN: |
| 6505 | return gen_protochain((int)v, proto, dir); |
| 6506 | |
| 6507 | case Q_UNDEF: |
| 6508 | syntax(); |
| 6509 | /* NOTREACHED */ |
| 6510 | |
| 6511 | default: |
| 6512 | abort(); |
| 6513 | /* NOTREACHED */ |
| 6514 | } |
| 6515 | /* NOTREACHED */ |
| 6516 | } |
| 6517 | |
| 6518 | #ifdef INET6 |
| 6519 | struct block * |
| 6520 | gen_mcode6(s1, s2, masklen, q) |
| 6521 | register const char *s1, *s2; |
| 6522 | register int masklen; |
| 6523 | struct qual q; |
| 6524 | { |
| 6525 | struct addrinfo *res; |
| 6526 | struct in6_addr *addr; |
| 6527 | struct in6_addr mask; |
| 6528 | struct block *b; |
| 6529 | u_int32_t *a, *m; |
| 6530 | |
| 6531 | if (s2) |
| 6532 | bpf_error("no mask %s supported", s2); |
| 6533 | |
| 6534 | res = pcap_nametoaddrinfo(s1); |
| 6535 | if (!res) |
| 6536 | bpf_error("invalid ip6 address %s", s1); |
| 6537 | ai = res; |
| 6538 | if (res->ai_next) |
| 6539 | bpf_error("%s resolved to multiple address", s1); |
| 6540 | addr = &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr; |
| 6541 | |
| 6542 | if (sizeof(mask) * 8 < masklen) |
| 6543 | bpf_error("mask length must be <= %u", (unsigned int)(sizeof(mask) * 8)); |
| 6544 | memset(&mask, 0, sizeof(mask)); |
| 6545 | memset(&mask, 0xff, masklen / 8); |
| 6546 | if (masklen % 8) { |
| 6547 | mask.s6_addr[masklen / 8] = |
| 6548 | (0xff << (8 - masklen % 8)) & 0xff; |
| 6549 | } |
| 6550 | |
| 6551 | a = (u_int32_t *)addr; |
| 6552 | m = (u_int32_t *)&mask; |
| 6553 | if ((a[0] & ~m[0]) || (a[1] & ~m[1]) |
| 6554 | || (a[2] & ~m[2]) || (a[3] & ~m[3])) { |
| 6555 | bpf_error("non-network bits set in \"%s/%d\"", s1, masklen); |
| 6556 | } |
| 6557 | |
| 6558 | switch (q.addr) { |
| 6559 | |
| 6560 | case Q_DEFAULT: |
| 6561 | case Q_HOST: |
| 6562 | if (masklen != 128) |
| 6563 | bpf_error("Mask syntax for networks only"); |
| 6564 | /* FALLTHROUGH */ |
| 6565 | |
| 6566 | case Q_NET: |
| 6567 | b = gen_host6(addr, &mask, q.proto, q.dir, q.addr); |
| 6568 | ai = NULL; |
| 6569 | freeaddrinfo(res); |
| 6570 | return b; |
| 6571 | |
| 6572 | default: |
| 6573 | bpf_error("invalid qualifier against IPv6 address"); |
| 6574 | /* NOTREACHED */ |
| 6575 | } |
| 6576 | return NULL; |
| 6577 | } |
| 6578 | #endif /*INET6*/ |
| 6579 | |
| 6580 | struct block * |
| 6581 | gen_ecode(eaddr, q) |
| 6582 | register const u_char *eaddr; |
| 6583 | struct qual q; |
| 6584 | { |
| 6585 | struct block *b, *tmp; |
| 6586 | |
| 6587 | if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) { |
| 6588 | switch (linktype) { |
| 6589 | case DLT_EN10MB: |
| 6590 | case DLT_NETANALYZER: |
| 6591 | case DLT_NETANALYZER_TRANSPARENT: |
| 6592 | return gen_ehostop(eaddr, (int)q.dir); |
| 6593 | case DLT_FDDI: |
| 6594 | return gen_fhostop(eaddr, (int)q.dir); |
| 6595 | case DLT_IEEE802: |
| 6596 | return gen_thostop(eaddr, (int)q.dir); |
| 6597 | case DLT_IEEE802_11: |
| 6598 | case DLT_PRISM_HEADER: |
| 6599 | case DLT_IEEE802_11_RADIO_AVS: |
| 6600 | case DLT_IEEE802_11_RADIO: |
| 6601 | case DLT_PPI: |
| 6602 | return gen_wlanhostop(eaddr, (int)q.dir); |
| 6603 | case DLT_SUNATM: |
| 6604 | if (is_lane) { |
| 6605 | /* |
| 6606 | * Check that the packet doesn't begin with an |
| 6607 | * LE Control marker. (We've already generated |
| 6608 | * a test for LANE.) |
| 6609 | */ |
| 6610 | tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H, |
| 6611 | 0xFF00); |
| 6612 | gen_not(tmp); |
| 6613 | |
| 6614 | /* |
| 6615 | * Now check the MAC address. |
| 6616 | */ |
| 6617 | b = gen_ehostop(eaddr, (int)q.dir); |
| 6618 | gen_and(tmp, b); |
| 6619 | return b; |
| 6620 | } |
| 6621 | break; |
| 6622 | case DLT_IP_OVER_FC: |
| 6623 | return gen_ipfchostop(eaddr, (int)q.dir); |
| 6624 | default: |
| 6625 | bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel"); |
| 6626 | break; |
| 6627 | } |
| 6628 | } |
| 6629 | bpf_error("ethernet address used in non-ether expression"); |
| 6630 | /* NOTREACHED */ |
| 6631 | return NULL; |
| 6632 | } |
| 6633 | |
| 6634 | void |
| 6635 | sappend(s0, s1) |
| 6636 | struct slist *s0, *s1; |
| 6637 | { |
| 6638 | /* |
| 6639 | * This is definitely not the best way to do this, but the |
| 6640 | * lists will rarely get long. |
| 6641 | */ |
| 6642 | while (s0->next) |
| 6643 | s0 = s0->next; |
| 6644 | s0->next = s1; |
| 6645 | } |
| 6646 | |
| 6647 | static struct slist * |
| 6648 | xfer_to_x(a) |
| 6649 | struct arth *a; |
| 6650 | { |
| 6651 | struct slist *s; |
| 6652 | |
| 6653 | s = new_stmt(BPF_LDX|BPF_MEM); |
| 6654 | s->s.k = a->regno; |
| 6655 | return s; |
| 6656 | } |
| 6657 | |
| 6658 | static struct slist * |
| 6659 | xfer_to_a(a) |
| 6660 | struct arth *a; |
| 6661 | { |
| 6662 | struct slist *s; |
| 6663 | |
| 6664 | s = new_stmt(BPF_LD|BPF_MEM); |
| 6665 | s->s.k = a->regno; |
| 6666 | return s; |
| 6667 | } |
| 6668 | |
| 6669 | /* |
| 6670 | * Modify "index" to use the value stored into its register as an |
| 6671 | * offset relative to the beginning of the header for the protocol |
| 6672 | * "proto", and allocate a register and put an item "size" bytes long |
| 6673 | * (1, 2, or 4) at that offset into that register, making it the register |
| 6674 | * for "index". |
| 6675 | */ |
| 6676 | struct arth * |
| 6677 | gen_load(proto, inst, size) |
| 6678 | int proto; |
| 6679 | struct arth *inst; |
| 6680 | int size; |
| 6681 | { |
| 6682 | struct slist *s, *tmp; |
| 6683 | struct block *b; |
| 6684 | int regno = alloc_reg(); |
| 6685 | |
| 6686 | free_reg(inst->regno); |
| 6687 | switch (size) { |
| 6688 | |
| 6689 | default: |
| 6690 | bpf_error("data size must be 1, 2, or 4"); |
| 6691 | |
| 6692 | case 1: |
| 6693 | size = BPF_B; |
| 6694 | break; |
| 6695 | |
| 6696 | case 2: |
| 6697 | size = BPF_H; |
| 6698 | break; |
| 6699 | |
| 6700 | case 4: |
| 6701 | size = BPF_W; |
| 6702 | break; |
| 6703 | } |
| 6704 | switch (proto) { |
| 6705 | default: |
| 6706 | bpf_error("unsupported index operation"); |
| 6707 | |
| 6708 | case Q_RADIO: |
| 6709 | /* |
| 6710 | * The offset is relative to the beginning of the packet |
| 6711 | * data, if we have a radio header. (If we don't, this |
| 6712 | * is an error.) |
| 6713 | */ |
| 6714 | if (linktype != DLT_IEEE802_11_RADIO_AVS && |
| 6715 | linktype != DLT_IEEE802_11_RADIO && |
| 6716 | linktype != DLT_PRISM_HEADER) |
| 6717 | bpf_error("radio information not present in capture"); |
| 6718 | |
| 6719 | /* |
| 6720 | * Load into the X register the offset computed into the |
| 6721 | * register specified by "index". |
| 6722 | */ |
| 6723 | s = xfer_to_x(inst); |
| 6724 | |
| 6725 | /* |
| 6726 | * Load the item at that offset. |
| 6727 | */ |
| 6728 | tmp = new_stmt(BPF_LD|BPF_IND|size); |
| 6729 | sappend(s, tmp); |
| 6730 | sappend(inst->s, s); |
| 6731 | break; |
| 6732 | |
| 6733 | case Q_LINK: |
| 6734 | /* |
| 6735 | * The offset is relative to the beginning of |
| 6736 | * the link-layer header. |
| 6737 | * |
| 6738 | * XXX - what about ATM LANE? Should the index be |
| 6739 | * relative to the beginning of the AAL5 frame, so |
| 6740 | * that 0 refers to the beginning of the LE Control |
| 6741 | * field, or relative to the beginning of the LAN |
| 6742 | * frame, so that 0 refers, for Ethernet LANE, to |
| 6743 | * the beginning of the destination address? |
| 6744 | */ |
| 6745 | s = gen_llprefixlen(); |
| 6746 | |
| 6747 | /* |
| 6748 | * If "s" is non-null, it has code to arrange that the |
| 6749 | * X register contains the length of the prefix preceding |
| 6750 | * the link-layer header. Add to it the offset computed |
| 6751 | * into the register specified by "index", and move that |
| 6752 | * into the X register. Otherwise, just load into the X |
| 6753 | * register the offset computed into the register specified |
| 6754 | * by "index". |
| 6755 | */ |
| 6756 | if (s != NULL) { |
| 6757 | sappend(s, xfer_to_a(inst)); |
| 6758 | sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X)); |
| 6759 | sappend(s, new_stmt(BPF_MISC|BPF_TAX)); |
| 6760 | } else |
| 6761 | s = xfer_to_x(inst); |
| 6762 | |
| 6763 | /* |
| 6764 | * Load the item at the sum of the offset we've put in the |
| 6765 | * X register and the offset of the start of the link |
| 6766 | * layer header (which is 0 if the radio header is |
| 6767 | * variable-length; that header length is what we put |
| 6768 | * into the X register and then added to the index). |
| 6769 | */ |
| 6770 | tmp = new_stmt(BPF_LD|BPF_IND|size); |
| 6771 | tmp->s.k = off_ll; |
| 6772 | sappend(s, tmp); |
| 6773 | sappend(inst->s, s); |
| 6774 | break; |
| 6775 | |
| 6776 | case Q_IP: |
| 6777 | case Q_ARP: |
| 6778 | case Q_RARP: |
| 6779 | case Q_ATALK: |
| 6780 | case Q_DECNET: |
| 6781 | case Q_SCA: |
| 6782 | case Q_LAT: |
| 6783 | case Q_MOPRC: |
| 6784 | case Q_MOPDL: |
| 6785 | #ifdef INET6 |
| 6786 | case Q_IPV6: |
| 6787 | #endif |
| 6788 | /* |
| 6789 | * The offset is relative to the beginning of |
| 6790 | * the network-layer header. |
| 6791 | * XXX - are there any cases where we want |
| 6792 | * off_nl_nosnap? |
| 6793 | */ |
| 6794 | s = gen_off_macpl(); |
| 6795 | |
| 6796 | /* |
| 6797 | * If "s" is non-null, it has code to arrange that the |
| 6798 | * X register contains the offset of the MAC-layer |
| 6799 | * payload. Add to it the offset computed into the |
| 6800 | * register specified by "index", and move that into |
| 6801 | * the X register. Otherwise, just load into the X |
| 6802 | * register the offset computed into the register specified |
| 6803 | * by "index". |
| 6804 | */ |
| 6805 | if (s != NULL) { |
| 6806 | sappend(s, xfer_to_a(inst)); |
| 6807 | sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X)); |
| 6808 | sappend(s, new_stmt(BPF_MISC|BPF_TAX)); |
| 6809 | } else |
| 6810 | s = xfer_to_x(inst); |
| 6811 | |
| 6812 | /* |
| 6813 | * Load the item at the sum of the offset we've put in the |
| 6814 | * X register, the offset of the start of the network |
| 6815 | * layer header from the beginning of the MAC-layer |
| 6816 | * payload, and the purported offset of the start of the |
| 6817 | * MAC-layer payload (which might be 0 if there's a |
| 6818 | * variable-length prefix before the link-layer header |
| 6819 | * or the link-layer header itself is variable-length; |
| 6820 | * the variable-length offset of the start of the |
| 6821 | * MAC-layer payload is what we put into the X register |
| 6822 | * and then added to the index). |
| 6823 | */ |
| 6824 | tmp = new_stmt(BPF_LD|BPF_IND|size); |
| 6825 | tmp->s.k = off_macpl + off_nl; |
| 6826 | sappend(s, tmp); |
| 6827 | sappend(inst->s, s); |
| 6828 | |
| 6829 | /* |
| 6830 | * Do the computation only if the packet contains |
| 6831 | * the protocol in question. |
| 6832 | */ |
| 6833 | b = gen_proto_abbrev(proto); |
| 6834 | if (inst->b) |
| 6835 | gen_and(inst->b, b); |
| 6836 | inst->b = b; |
| 6837 | break; |
| 6838 | |
| 6839 | case Q_SCTP: |
| 6840 | case Q_TCP: |
| 6841 | case Q_UDP: |
| 6842 | case Q_ICMP: |
| 6843 | case Q_IGMP: |
| 6844 | case Q_IGRP: |
| 6845 | case Q_PIM: |
| 6846 | case Q_VRRP: |
| 6847 | case Q_CARP: |
| 6848 | /* |
| 6849 | * The offset is relative to the beginning of |
| 6850 | * the transport-layer header. |
| 6851 | * |
| 6852 | * Load the X register with the length of the IPv4 header |
| 6853 | * (plus the offset of the link-layer header, if it's |
| 6854 | * a variable-length header), in bytes. |
| 6855 | * |
| 6856 | * XXX - are there any cases where we want |
| 6857 | * off_nl_nosnap? |
| 6858 | * XXX - we should, if we're built with |
| 6859 | * IPv6 support, generate code to load either |
| 6860 | * IPv4, IPv6, or both, as appropriate. |
| 6861 | */ |
| 6862 | s = gen_loadx_iphdrlen(); |
| 6863 | |
| 6864 | /* |
| 6865 | * The X register now contains the sum of the length |
| 6866 | * of any variable-length header preceding the link-layer |
| 6867 | * header, any variable-length link-layer header, and the |
| 6868 | * length of the network-layer header. |
| 6869 | * |
| 6870 | * Load into the A register the offset relative to |
| 6871 | * the beginning of the transport layer header, |
| 6872 | * add the X register to that, move that to the |
| 6873 | * X register, and load with an offset from the |
| 6874 | * X register equal to the offset of the network |
| 6875 | * layer header relative to the beginning of |
| 6876 | * the MAC-layer payload plus the fixed-length |
| 6877 | * portion of the offset of the MAC-layer payload |
| 6878 | * from the beginning of the raw packet data. |
| 6879 | */ |
| 6880 | sappend(s, xfer_to_a(inst)); |
| 6881 | sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X)); |
| 6882 | sappend(s, new_stmt(BPF_MISC|BPF_TAX)); |
| 6883 | sappend(s, tmp = new_stmt(BPF_LD|BPF_IND|size)); |
| 6884 | tmp->s.k = off_macpl + off_nl; |
| 6885 | sappend(inst->s, s); |
| 6886 | |
| 6887 | /* |
| 6888 | * Do the computation only if the packet contains |
| 6889 | * the protocol in question - which is true only |
| 6890 | * if this is an IP datagram and is the first or |
| 6891 | * only fragment of that datagram. |
| 6892 | */ |
| 6893 | gen_and(gen_proto_abbrev(proto), b = gen_ipfrag()); |
| 6894 | if (inst->b) |
| 6895 | gen_and(inst->b, b); |
| 6896 | #ifdef INET6 |
| 6897 | gen_and(gen_proto_abbrev(Q_IP), b); |
| 6898 | #endif |
| 6899 | inst->b = b; |
| 6900 | break; |
| 6901 | #ifdef INET6 |
| 6902 | case Q_ICMPV6: |
| 6903 | bpf_error("IPv6 upper-layer protocol is not supported by proto[x]"); |
| 6904 | /*NOTREACHED*/ |
| 6905 | #endif |
| 6906 | } |
| 6907 | inst->regno = regno; |
| 6908 | s = new_stmt(BPF_ST); |
| 6909 | s->s.k = regno; |
| 6910 | sappend(inst->s, s); |
| 6911 | |
| 6912 | return inst; |
| 6913 | } |
| 6914 | |
| 6915 | struct block * |
| 6916 | gen_relation(code, a0, a1, reversed) |
| 6917 | int code; |
| 6918 | struct arth *a0, *a1; |
| 6919 | int reversed; |
| 6920 | { |
| 6921 | struct slist *s0, *s1, *s2; |
| 6922 | struct block *b, *tmp; |
| 6923 | |
| 6924 | s0 = xfer_to_x(a1); |
| 6925 | s1 = xfer_to_a(a0); |
| 6926 | if (code == BPF_JEQ) { |
| 6927 | s2 = new_stmt(BPF_ALU|BPF_SUB|BPF_X); |
| 6928 | b = new_block(JMP(code)); |
| 6929 | sappend(s1, s2); |
| 6930 | } |
| 6931 | else |
| 6932 | b = new_block(BPF_JMP|code|BPF_X); |
| 6933 | if (reversed) |
| 6934 | gen_not(b); |
| 6935 | |
| 6936 | sappend(s0, s1); |
| 6937 | sappend(a1->s, s0); |
| 6938 | sappend(a0->s, a1->s); |
| 6939 | |
| 6940 | b->stmts = a0->s; |
| 6941 | |
| 6942 | free_reg(a0->regno); |
| 6943 | free_reg(a1->regno); |
| 6944 | |
| 6945 | /* 'and' together protocol checks */ |
| 6946 | if (a0->b) { |
| 6947 | if (a1->b) { |
| 6948 | gen_and(a0->b, tmp = a1->b); |
| 6949 | } |
| 6950 | else |
| 6951 | tmp = a0->b; |
| 6952 | } else |
| 6953 | tmp = a1->b; |
| 6954 | |
| 6955 | if (tmp) |
| 6956 | gen_and(tmp, b); |
| 6957 | |
| 6958 | return b; |
| 6959 | } |
| 6960 | |
| 6961 | struct arth * |
| 6962 | gen_loadlen() |
| 6963 | { |
| 6964 | int regno = alloc_reg(); |
| 6965 | struct arth *a = (struct arth *)newchunk(sizeof(*a)); |
| 6966 | struct slist *s; |
| 6967 | |
| 6968 | s = new_stmt(BPF_LD|BPF_LEN); |
| 6969 | s->next = new_stmt(BPF_ST); |
| 6970 | s->next->s.k = regno; |
| 6971 | a->s = s; |
| 6972 | a->regno = regno; |
| 6973 | |
| 6974 | return a; |
| 6975 | } |
| 6976 | |
| 6977 | struct arth * |
| 6978 | gen_loadi(val) |
| 6979 | int val; |
| 6980 | { |
| 6981 | struct arth *a; |
| 6982 | struct slist *s; |
| 6983 | int reg; |
| 6984 | |
| 6985 | a = (struct arth *)newchunk(sizeof(*a)); |
| 6986 | |
| 6987 | reg = alloc_reg(); |
| 6988 | |
| 6989 | s = new_stmt(BPF_LD|BPF_IMM); |
| 6990 | s->s.k = val; |
| 6991 | s->next = new_stmt(BPF_ST); |
| 6992 | s->next->s.k = reg; |
| 6993 | a->s = s; |
| 6994 | a->regno = reg; |
| 6995 | |
| 6996 | return a; |
| 6997 | } |
| 6998 | |
| 6999 | struct arth * |
| 7000 | gen_neg(a) |
| 7001 | struct arth *a; |
| 7002 | { |
| 7003 | struct slist *s; |
| 7004 | |
| 7005 | s = xfer_to_a(a); |
| 7006 | sappend(a->s, s); |
| 7007 | s = new_stmt(BPF_ALU|BPF_NEG); |
| 7008 | s->s.k = 0; |
| 7009 | sappend(a->s, s); |
| 7010 | s = new_stmt(BPF_ST); |
| 7011 | s->s.k = a->regno; |
| 7012 | sappend(a->s, s); |
| 7013 | |
| 7014 | return a; |
| 7015 | } |
| 7016 | |
| 7017 | struct arth * |
| 7018 | gen_arth(code, a0, a1) |
| 7019 | int code; |
| 7020 | struct arth *a0, *a1; |
| 7021 | { |
| 7022 | struct slist *s0, *s1, *s2; |
| 7023 | |
| 7024 | s0 = xfer_to_x(a1); |
| 7025 | s1 = xfer_to_a(a0); |
| 7026 | s2 = new_stmt(BPF_ALU|BPF_X|code); |
| 7027 | |
| 7028 | sappend(s1, s2); |
| 7029 | sappend(s0, s1); |
| 7030 | sappend(a1->s, s0); |
| 7031 | sappend(a0->s, a1->s); |
| 7032 | |
| 7033 | free_reg(a0->regno); |
| 7034 | free_reg(a1->regno); |
| 7035 | |
| 7036 | s0 = new_stmt(BPF_ST); |
| 7037 | a0->regno = s0->s.k = alloc_reg(); |
| 7038 | sappend(a0->s, s0); |
| 7039 | |
| 7040 | return a0; |
| 7041 | } |
| 7042 | |
| 7043 | /* |
| 7044 | * Here we handle simple allocation of the scratch registers. |
| 7045 | * If too many registers are alloc'd, the allocator punts. |
| 7046 | */ |
| 7047 | static int regused[BPF_MEMWORDS]; |
| 7048 | static int curreg; |
| 7049 | |
| 7050 | /* |
| 7051 | * Initialize the table of used registers and the current register. |
| 7052 | */ |
| 7053 | static void |
| 7054 | init_regs() |
| 7055 | { |
| 7056 | curreg = 0; |
| 7057 | memset(regused, 0, sizeof regused); |
| 7058 | } |
| 7059 | |
| 7060 | /* |
| 7061 | * Return the next free register. |
| 7062 | */ |
| 7063 | static int |
| 7064 | alloc_reg() |
| 7065 | { |
| 7066 | int n = BPF_MEMWORDS; |
| 7067 | |
| 7068 | while (--n >= 0) { |
| 7069 | if (regused[curreg]) |
| 7070 | curreg = (curreg + 1) % BPF_MEMWORDS; |
| 7071 | else { |
| 7072 | regused[curreg] = 1; |
| 7073 | return curreg; |
| 7074 | } |
| 7075 | } |
| 7076 | bpf_error("too many registers needed to evaluate expression"); |
| 7077 | /* NOTREACHED */ |
| 7078 | return 0; |
| 7079 | } |
| 7080 | |
| 7081 | /* |
| 7082 | * Return a register to the table so it can |
| 7083 | * be used later. |
| 7084 | */ |
| 7085 | static void |
| 7086 | free_reg(n) |
| 7087 | int n; |
| 7088 | { |
| 7089 | regused[n] = 0; |
| 7090 | } |
| 7091 | |
| 7092 | static struct block * |
| 7093 | gen_len(jmp, n) |
| 7094 | int jmp, n; |
| 7095 | { |
| 7096 | struct slist *s; |
| 7097 | struct block *b; |
| 7098 | |
| 7099 | s = new_stmt(BPF_LD|BPF_LEN); |
| 7100 | b = new_block(JMP(jmp)); |
| 7101 | b->stmts = s; |
| 7102 | b->s.k = n; |
| 7103 | |
| 7104 | return b; |
| 7105 | } |
| 7106 | |
| 7107 | struct block * |
| 7108 | gen_greater(n) |
| 7109 | int n; |
| 7110 | { |
| 7111 | return gen_len(BPF_JGE, n); |
| 7112 | } |
| 7113 | |
| 7114 | /* |
| 7115 | * Actually, this is less than or equal. |
| 7116 | */ |
| 7117 | struct block * |
| 7118 | gen_less(n) |
| 7119 | int n; |
| 7120 | { |
| 7121 | struct block *b; |
| 7122 | |
| 7123 | b = gen_len(BPF_JGT, n); |
| 7124 | gen_not(b); |
| 7125 | |
| 7126 | return b; |
| 7127 | } |
| 7128 | |
| 7129 | /* |
| 7130 | * This is for "byte {idx} {op} {val}"; "idx" is treated as relative to |
| 7131 | * the beginning of the link-layer header. |
| 7132 | * XXX - that means you can't test values in the radiotap header, but |
| 7133 | * as that header is difficult if not impossible to parse generally |
| 7134 | * without a loop, that might not be a severe problem. A new keyword |
| 7135 | * "radio" could be added for that, although what you'd really want |
| 7136 | * would be a way of testing particular radio header values, which |
| 7137 | * would generate code appropriate to the radio header in question. |
| 7138 | */ |
| 7139 | struct block * |
| 7140 | gen_byteop(op, idx, val) |
| 7141 | int op, idx, val; |
| 7142 | { |
| 7143 | struct block *b; |
| 7144 | struct slist *s; |
| 7145 | |
| 7146 | switch (op) { |
| 7147 | default: |
| 7148 | abort(); |
| 7149 | |
| 7150 | case '=': |
| 7151 | return gen_cmp(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val); |
| 7152 | |
| 7153 | case '<': |
| 7154 | b = gen_cmp_lt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val); |
| 7155 | return b; |
| 7156 | |
| 7157 | case '>': |
| 7158 | b = gen_cmp_gt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val); |
| 7159 | return b; |
| 7160 | |
| 7161 | case '|': |
| 7162 | s = new_stmt(BPF_ALU|BPF_OR|BPF_K); |
| 7163 | break; |
| 7164 | |
| 7165 | case '&': |
| 7166 | s = new_stmt(BPF_ALU|BPF_AND|BPF_K); |
| 7167 | break; |
| 7168 | } |
| 7169 | s->s.k = val; |
| 7170 | b = new_block(JMP(BPF_JEQ)); |
| 7171 | b->stmts = s; |
| 7172 | gen_not(b); |
| 7173 | |
| 7174 | return b; |
| 7175 | } |
| 7176 | |
| 7177 | static u_char abroadcast[] = { 0x0 }; |
| 7178 | |
| 7179 | struct block * |
| 7180 | gen_broadcast(proto) |
| 7181 | int proto; |
| 7182 | { |
| 7183 | bpf_u_int32 hostmask; |
| 7184 | struct block *b0, *b1, *b2; |
| 7185 | static u_char ebroadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; |
| 7186 | |
| 7187 | switch (proto) { |
| 7188 | |
| 7189 | case Q_DEFAULT: |
| 7190 | case Q_LINK: |
| 7191 | switch (linktype) { |
| 7192 | case DLT_ARCNET: |
| 7193 | case DLT_ARCNET_LINUX: |
| 7194 | return gen_ahostop(abroadcast, Q_DST); |
| 7195 | case DLT_EN10MB: |
| 7196 | case DLT_NETANALYZER: |
| 7197 | case DLT_NETANALYZER_TRANSPARENT: |
| 7198 | return gen_ehostop(ebroadcast, Q_DST); |
| 7199 | case DLT_FDDI: |
| 7200 | return gen_fhostop(ebroadcast, Q_DST); |
| 7201 | case DLT_IEEE802: |
| 7202 | return gen_thostop(ebroadcast, Q_DST); |
| 7203 | case DLT_IEEE802_11: |
| 7204 | case DLT_PRISM_HEADER: |
| 7205 | case DLT_IEEE802_11_RADIO_AVS: |
| 7206 | case DLT_IEEE802_11_RADIO: |
| 7207 | case DLT_PPI: |
| 7208 | return gen_wlanhostop(ebroadcast, Q_DST); |
| 7209 | case DLT_IP_OVER_FC: |
| 7210 | return gen_ipfchostop(ebroadcast, Q_DST); |
| 7211 | case DLT_SUNATM: |
| 7212 | if (is_lane) { |
| 7213 | /* |
| 7214 | * Check that the packet doesn't begin with an |
| 7215 | * LE Control marker. (We've already generated |
| 7216 | * a test for LANE.) |
| 7217 | */ |
| 7218 | b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, |
| 7219 | BPF_H, 0xFF00); |
| 7220 | gen_not(b1); |
| 7221 | |
| 7222 | /* |
| 7223 | * Now check the MAC address. |
| 7224 | */ |
| 7225 | b0 = gen_ehostop(ebroadcast, Q_DST); |
| 7226 | gen_and(b1, b0); |
| 7227 | return b0; |
| 7228 | } |
| 7229 | break; |
| 7230 | default: |
| 7231 | bpf_error("not a broadcast link"); |
| 7232 | } |
| 7233 | break; |
| 7234 | |
| 7235 | case Q_IP: |
| 7236 | /* |
| 7237 | * We treat a netmask of PCAP_NETMASK_UNKNOWN (0xffffffff) |
| 7238 | * as an indication that we don't know the netmask, and fail |
| 7239 | * in that case. |
| 7240 | */ |
| 7241 | if (netmask == PCAP_NETMASK_UNKNOWN) |
| 7242 | bpf_error("netmask not known, so 'ip broadcast' not supported"); |
| 7243 | b0 = gen_linktype(ETHERTYPE_IP); |
| 7244 | hostmask = ~netmask; |
| 7245 | b1 = gen_mcmp(OR_NET, 16, BPF_W, (bpf_int32)0, hostmask); |
| 7246 | b2 = gen_mcmp(OR_NET, 16, BPF_W, |
| 7247 | (bpf_int32)(~0 & hostmask), hostmask); |
| 7248 | gen_or(b1, b2); |
| 7249 | gen_and(b0, b2); |
| 7250 | return b2; |
| 7251 | } |
| 7252 | bpf_error("only link-layer/IP broadcast filters supported"); |
| 7253 | /* NOTREACHED */ |
| 7254 | return NULL; |
| 7255 | } |
| 7256 | |
| 7257 | /* |
| 7258 | * Generate code to test the low-order bit of a MAC address (that's |
| 7259 | * the bottom bit of the *first* byte). |
| 7260 | */ |
| 7261 | static struct block * |
| 7262 | gen_mac_multicast(offset) |
| 7263 | int offset; |
| 7264 | { |
| 7265 | register struct block *b0; |
| 7266 | register struct slist *s; |
| 7267 | |
| 7268 | /* link[offset] & 1 != 0 */ |
| 7269 | s = gen_load_a(OR_LINK, offset, BPF_B); |
| 7270 | b0 = new_block(JMP(BPF_JSET)); |
| 7271 | b0->s.k = 1; |
| 7272 | b0->stmts = s; |
| 7273 | return b0; |
| 7274 | } |
| 7275 | |
| 7276 | struct block * |
| 7277 | gen_multicast(proto) |
| 7278 | int proto; |
| 7279 | { |
| 7280 | register struct block *b0, *b1, *b2; |
| 7281 | register struct slist *s; |
| 7282 | |
| 7283 | switch (proto) { |
| 7284 | |
| 7285 | case Q_DEFAULT: |
| 7286 | case Q_LINK: |
| 7287 | switch (linktype) { |
| 7288 | case DLT_ARCNET: |
| 7289 | case DLT_ARCNET_LINUX: |
| 7290 | /* all ARCnet multicasts use the same address */ |
| 7291 | return gen_ahostop(abroadcast, Q_DST); |
| 7292 | case DLT_EN10MB: |
| 7293 | case DLT_NETANALYZER: |
| 7294 | case DLT_NETANALYZER_TRANSPARENT: |
| 7295 | /* ether[0] & 1 != 0 */ |
| 7296 | return gen_mac_multicast(0); |
| 7297 | case DLT_FDDI: |
| 7298 | /* |
| 7299 | * XXX TEST THIS: MIGHT NOT PORT PROPERLY XXX |
| 7300 | * |
| 7301 | * XXX - was that referring to bit-order issues? |
| 7302 | */ |
| 7303 | /* fddi[1] & 1 != 0 */ |
| 7304 | return gen_mac_multicast(1); |
| 7305 | case DLT_IEEE802: |
| 7306 | /* tr[2] & 1 != 0 */ |
| 7307 | return gen_mac_multicast(2); |
| 7308 | case DLT_IEEE802_11: |
| 7309 | case DLT_PRISM_HEADER: |
| 7310 | case DLT_IEEE802_11_RADIO_AVS: |
| 7311 | case DLT_IEEE802_11_RADIO: |
| 7312 | case DLT_PPI: |
| 7313 | /* |
| 7314 | * Oh, yuk. |
| 7315 | * |
| 7316 | * For control frames, there is no DA. |
| 7317 | * |
| 7318 | * For management frames, DA is at an |
| 7319 | * offset of 4 from the beginning of |
| 7320 | * the packet. |
| 7321 | * |
| 7322 | * For data frames, DA is at an offset |
| 7323 | * of 4 from the beginning of the packet |
| 7324 | * if To DS is clear and at an offset of |
| 7325 | * 16 from the beginning of the packet |
| 7326 | * if To DS is set. |
| 7327 | */ |
| 7328 | |
| 7329 | /* |
| 7330 | * Generate the tests to be done for data frames. |
| 7331 | * |
| 7332 | * First, check for To DS set, i.e. "link[1] & 0x01". |
| 7333 | */ |
| 7334 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 7335 | b1 = new_block(JMP(BPF_JSET)); |
| 7336 | b1->s.k = 0x01; /* To DS */ |
| 7337 | b1->stmts = s; |
| 7338 | |
| 7339 | /* |
| 7340 | * If To DS is set, the DA is at 16. |
| 7341 | */ |
| 7342 | b0 = gen_mac_multicast(16); |
| 7343 | gen_and(b1, b0); |
| 7344 | |
| 7345 | /* |
| 7346 | * Now, check for To DS not set, i.e. check |
| 7347 | * "!(link[1] & 0x01)". |
| 7348 | */ |
| 7349 | s = gen_load_a(OR_LINK, 1, BPF_B); |
| 7350 | b2 = new_block(JMP(BPF_JSET)); |
| 7351 | b2->s.k = 0x01; /* To DS */ |
| 7352 | b2->stmts = s; |
| 7353 | gen_not(b2); |
| 7354 | |
| 7355 | /* |
| 7356 | * If To DS is not set, the DA is at 4. |
| 7357 | */ |
| 7358 | b1 = gen_mac_multicast(4); |
| 7359 | gen_and(b2, b1); |
| 7360 | |
| 7361 | /* |
| 7362 | * Now OR together the last two checks. That gives |
| 7363 | * the complete set of checks for data frames. |
| 7364 | */ |
| 7365 | gen_or(b1, b0); |
| 7366 | |
| 7367 | /* |
| 7368 | * Now check for a data frame. |
| 7369 | * I.e, check "link[0] & 0x08". |
| 7370 | */ |
| 7371 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 7372 | b1 = new_block(JMP(BPF_JSET)); |
| 7373 | b1->s.k = 0x08; |
| 7374 | b1->stmts = s; |
| 7375 | |
| 7376 | /* |
| 7377 | * AND that with the checks done for data frames. |
| 7378 | */ |
| 7379 | gen_and(b1, b0); |
| 7380 | |
| 7381 | /* |
| 7382 | * If the high-order bit of the type value is 0, this |
| 7383 | * is a management frame. |
| 7384 | * I.e, check "!(link[0] & 0x08)". |
| 7385 | */ |
| 7386 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 7387 | b2 = new_block(JMP(BPF_JSET)); |
| 7388 | b2->s.k = 0x08; |
| 7389 | b2->stmts = s; |
| 7390 | gen_not(b2); |
| 7391 | |
| 7392 | /* |
| 7393 | * For management frames, the DA is at 4. |
| 7394 | */ |
| 7395 | b1 = gen_mac_multicast(4); |
| 7396 | gen_and(b2, b1); |
| 7397 | |
| 7398 | /* |
| 7399 | * OR that with the checks done for data frames. |
| 7400 | * That gives the checks done for management and |
| 7401 | * data frames. |
| 7402 | */ |
| 7403 | gen_or(b1, b0); |
| 7404 | |
| 7405 | /* |
| 7406 | * If the low-order bit of the type value is 1, |
| 7407 | * this is either a control frame or a frame |
| 7408 | * with a reserved type, and thus not a |
| 7409 | * frame with an SA. |
| 7410 | * |
| 7411 | * I.e., check "!(link[0] & 0x04)". |
| 7412 | */ |
| 7413 | s = gen_load_a(OR_LINK, 0, BPF_B); |
| 7414 | b1 = new_block(JMP(BPF_JSET)); |
| 7415 | b1->s.k = 0x04; |
| 7416 | b1->stmts = s; |
| 7417 | gen_not(b1); |
| 7418 | |
| 7419 | /* |
| 7420 | * AND that with the checks for data and management |
| 7421 | * frames. |
| 7422 | */ |
| 7423 | gen_and(b1, b0); |
| 7424 | return b0; |
| 7425 | case DLT_IP_OVER_FC: |
| 7426 | b0 = gen_mac_multicast(2); |
| 7427 | return b0; |
| 7428 | case DLT_SUNATM: |
| 7429 | if (is_lane) { |
| 7430 | /* |
| 7431 | * Check that the packet doesn't begin with an |
| 7432 | * LE Control marker. (We've already generated |
| 7433 | * a test for LANE.) |
| 7434 | */ |
| 7435 | b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, |
| 7436 | BPF_H, 0xFF00); |
| 7437 | gen_not(b1); |
| 7438 | |
| 7439 | /* ether[off_mac] & 1 != 0 */ |
| 7440 | b0 = gen_mac_multicast(off_mac); |
| 7441 | gen_and(b1, b0); |
| 7442 | return b0; |
| 7443 | } |
| 7444 | break; |
| 7445 | default: |
| 7446 | break; |
| 7447 | } |
| 7448 | /* Link not known to support multicasts */ |
| 7449 | break; |
| 7450 | |
| 7451 | case Q_IP: |
| 7452 | b0 = gen_linktype(ETHERTYPE_IP); |
| 7453 | b1 = gen_cmp_ge(OR_NET, 16, BPF_B, (bpf_int32)224); |
| 7454 | gen_and(b0, b1); |
| 7455 | return b1; |
| 7456 | |
| 7457 | #ifdef INET6 |
| 7458 | case Q_IPV6: |
| 7459 | b0 = gen_linktype(ETHERTYPE_IPV6); |
| 7460 | b1 = gen_cmp(OR_NET, 24, BPF_B, (bpf_int32)255); |
| 7461 | gen_and(b0, b1); |
| 7462 | return b1; |
| 7463 | #endif /* INET6 */ |
| 7464 | } |
| 7465 | bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel"); |
| 7466 | /* NOTREACHED */ |
| 7467 | return NULL; |
| 7468 | } |
| 7469 | |
| 7470 | /* |
| 7471 | * generate command for inbound/outbound. It's here so we can |
| 7472 | * make it link-type specific. 'dir' = 0 implies "inbound", |
| 7473 | * = 1 implies "outbound". |
| 7474 | */ |
| 7475 | struct block * |
| 7476 | gen_inbound(dir) |
| 7477 | int dir; |
| 7478 | { |
| 7479 | register struct block *b0; |
| 7480 | |
| 7481 | /* |
| 7482 | * Only some data link types support inbound/outbound qualifiers. |
| 7483 | */ |
| 7484 | switch (linktype) { |
| 7485 | case DLT_SLIP: |
| 7486 | b0 = gen_relation(BPF_JEQ, |
| 7487 | gen_load(Q_LINK, gen_loadi(0), 1), |
| 7488 | gen_loadi(0), |
| 7489 | dir); |
| 7490 | break; |
| 7491 | |
| 7492 | case DLT_IPNET: |
| 7493 | if (dir) { |
| 7494 | /* match outgoing packets */ |
| 7495 | b0 = gen_cmp(OR_LINK, 2, BPF_H, IPNET_OUTBOUND); |
| 7496 | } else { |
| 7497 | /* match incoming packets */ |
| 7498 | b0 = gen_cmp(OR_LINK, 2, BPF_H, IPNET_INBOUND); |
| 7499 | } |
| 7500 | break; |
| 7501 | |
| 7502 | case DLT_LINUX_SLL: |
| 7503 | if (dir) { |
| 7504 | /* |
| 7505 | * Match packets sent by this machine. |
| 7506 | */ |
| 7507 | b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_OUTGOING); |
| 7508 | } else { |
| 7509 | /* |
| 7510 | * Match packets sent to this machine. |
| 7511 | * (No broadcast or multicast packets, or |
| 7512 | * packets sent to some other machine and |
| 7513 | * received promiscuously.) |
| 7514 | * |
| 7515 | * XXX - packets sent to other machines probably |
| 7516 | * shouldn't be matched, but what about broadcast |
| 7517 | * or multicast packets we received? |
| 7518 | */ |
| 7519 | b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_HOST); |
| 7520 | } |
| 7521 | break; |
| 7522 | |
| 7523 | #ifdef HAVE_NET_PFVAR_H |
| 7524 | case DLT_PFLOG: |
| 7525 | b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, dir), BPF_B, |
| 7526 | (bpf_int32)((dir == 0) ? PF_IN : PF_OUT)); |
| 7527 | break; |
| 7528 | #endif |
| 7529 | |
| 7530 | case DLT_PPP_PPPD: |
| 7531 | if (dir) { |
| 7532 | /* match outgoing packets */ |
| 7533 | b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_OUT); |
| 7534 | } else { |
| 7535 | /* match incoming packets */ |
| 7536 | b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_IN); |
| 7537 | } |
| 7538 | break; |
| 7539 | |
| 7540 | case DLT_JUNIPER_MFR: |
| 7541 | case DLT_JUNIPER_MLFR: |
| 7542 | case DLT_JUNIPER_MLPPP: |
| 7543 | case DLT_JUNIPER_ATM1: |
| 7544 | case DLT_JUNIPER_ATM2: |
| 7545 | case DLT_JUNIPER_PPPOE: |
| 7546 | case DLT_JUNIPER_PPPOE_ATM: |
| 7547 | case DLT_JUNIPER_GGSN: |
| 7548 | case DLT_JUNIPER_ES: |
| 7549 | case DLT_JUNIPER_MONITOR: |
| 7550 | case DLT_JUNIPER_SERVICES: |
| 7551 | case DLT_JUNIPER_ETHER: |
| 7552 | case DLT_JUNIPER_PPP: |
| 7553 | case DLT_JUNIPER_FRELAY: |
| 7554 | case DLT_JUNIPER_CHDLC: |
| 7555 | case DLT_JUNIPER_VP: |
| 7556 | case DLT_JUNIPER_ST: |
| 7557 | case DLT_JUNIPER_ISM: |
| 7558 | case DLT_JUNIPER_VS: |
| 7559 | case DLT_JUNIPER_SRX_E2E: |
| 7560 | case DLT_JUNIPER_FIBRECHANNEL: |
| 7561 | case DLT_JUNIPER_ATM_CEMIC: |
| 7562 | |
| 7563 | /* juniper flags (including direction) are stored |
| 7564 | * the byte after the 3-byte magic number */ |
| 7565 | if (dir) { |
| 7566 | /* match outgoing packets */ |
| 7567 | b0 = gen_mcmp(OR_LINK, 3, BPF_B, 0, 0x01); |
| 7568 | } else { |
| 7569 | /* match incoming packets */ |
| 7570 | b0 = gen_mcmp(OR_LINK, 3, BPF_B, 1, 0x01); |
| 7571 | } |
| 7572 | break; |
| 7573 | |
| 7574 | default: |
| 7575 | bpf_error("inbound/outbound not supported on linktype %d", |
| 7576 | linktype); |
| 7577 | b0 = NULL; |
| 7578 | /* NOTREACHED */ |
| 7579 | } |
| 7580 | return (b0); |
| 7581 | } |
| 7582 | |
| 7583 | #ifdef HAVE_NET_PFVAR_H |
| 7584 | /* PF firewall log matched interface */ |
| 7585 | struct block * |
| 7586 | gen_pf_ifname(const char *ifname) |
| 7587 | { |
| 7588 | struct block *b0; |
| 7589 | u_int len, off; |
| 7590 | |
| 7591 | if (linktype != DLT_PFLOG) { |
| 7592 | bpf_error("ifname supported only on PF linktype"); |
| 7593 | /* NOTREACHED */ |
| 7594 | } |
| 7595 | len = sizeof(((struct pfloghdr *)0)->ifname); |
| 7596 | off = offsetof(struct pfloghdr, ifname); |
| 7597 | if (strlen(ifname) >= len) { |
| 7598 | bpf_error("ifname interface names can only be %d characters", |
| 7599 | len-1); |
| 7600 | /* NOTREACHED */ |
| 7601 | } |
| 7602 | b0 = gen_bcmp(OR_LINK, off, strlen(ifname), (const u_char *)ifname); |
| 7603 | return (b0); |
| 7604 | } |
| 7605 | |
| 7606 | /* PF firewall log ruleset name */ |
| 7607 | struct block * |
| 7608 | gen_pf_ruleset(char *ruleset) |
| 7609 | { |
| 7610 | struct block *b0; |
| 7611 | |
| 7612 | if (linktype != DLT_PFLOG) { |
| 7613 | bpf_error("ruleset supported only on PF linktype"); |
| 7614 | /* NOTREACHED */ |
| 7615 | } |
| 7616 | |
| 7617 | if (strlen(ruleset) >= sizeof(((struct pfloghdr *)0)->ruleset)) { |
| 7618 | bpf_error("ruleset names can only be %ld characters", |
| 7619 | (long)(sizeof(((struct pfloghdr *)0)->ruleset) - 1)); |
| 7620 | /* NOTREACHED */ |
| 7621 | } |
| 7622 | |
| 7623 | b0 = gen_bcmp(OR_LINK, offsetof(struct pfloghdr, ruleset), |
| 7624 | strlen(ruleset), (const u_char *)ruleset); |
| 7625 | return (b0); |
| 7626 | } |
| 7627 | |
| 7628 | /* PF firewall log rule number */ |
| 7629 | struct block * |
| 7630 | gen_pf_rnr(int rnr) |
| 7631 | { |
| 7632 | struct block *b0; |
| 7633 | |
| 7634 | if (linktype != DLT_PFLOG) { |
| 7635 | bpf_error("rnr supported only on PF linktype"); |
| 7636 | /* NOTREACHED */ |
| 7637 | } |
| 7638 | |
| 7639 | b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, rulenr), BPF_W, |
| 7640 | (bpf_int32)rnr); |
| 7641 | return (b0); |
| 7642 | } |
| 7643 | |
| 7644 | /* PF firewall log sub-rule number */ |
| 7645 | struct block * |
| 7646 | gen_pf_srnr(int srnr) |
| 7647 | { |
| 7648 | struct block *b0; |
| 7649 | |
| 7650 | if (linktype != DLT_PFLOG) { |
| 7651 | bpf_error("srnr supported only on PF linktype"); |
| 7652 | /* NOTREACHED */ |
| 7653 | } |
| 7654 | |
| 7655 | b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, subrulenr), BPF_W, |
| 7656 | (bpf_int32)srnr); |
| 7657 | return (b0); |
| 7658 | } |
| 7659 | |
| 7660 | /* PF firewall log reason code */ |
| 7661 | struct block * |
| 7662 | gen_pf_reason(int reason) |
| 7663 | { |
| 7664 | struct block *b0; |
| 7665 | |
| 7666 | if (linktype != DLT_PFLOG) { |
| 7667 | bpf_error("reason supported only on PF linktype"); |
| 7668 | /* NOTREACHED */ |
| 7669 | } |
| 7670 | |
| 7671 | b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, reason), BPF_B, |
| 7672 | (bpf_int32)reason); |
| 7673 | return (b0); |
| 7674 | } |
| 7675 | |
| 7676 | /* PF firewall log action */ |
| 7677 | struct block * |
| 7678 | gen_pf_action(int action) |
| 7679 | { |
| 7680 | struct block *b0; |
| 7681 | |
| 7682 | if (linktype != DLT_PFLOG) { |
| 7683 | bpf_error("action supported only on PF linktype"); |
| 7684 | /* NOTREACHED */ |
| 7685 | } |
| 7686 | |
| 7687 | b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, action), BPF_B, |
| 7688 | (bpf_int32)action); |
| 7689 | return (b0); |
| 7690 | } |
| 7691 | #else /* !HAVE_NET_PFVAR_H */ |
| 7692 | struct block * |
| 7693 | gen_pf_ifname(const char *ifname) |
| 7694 | { |
| 7695 | bpf_error("libpcap was compiled without pf support"); |
| 7696 | /* NOTREACHED */ |
| 7697 | return (NULL); |
| 7698 | } |
| 7699 | |
| 7700 | struct block * |
| 7701 | gen_pf_ruleset(char *ruleset) |
| 7702 | { |
| 7703 | bpf_error("libpcap was compiled on a machine without pf support"); |
| 7704 | /* NOTREACHED */ |
| 7705 | return (NULL); |
| 7706 | } |
| 7707 | |
| 7708 | struct block * |
| 7709 | gen_pf_rnr(int rnr) |
| 7710 | { |
| 7711 | bpf_error("libpcap was compiled on a machine without pf support"); |
| 7712 | /* NOTREACHED */ |
| 7713 | return (NULL); |
| 7714 | } |
| 7715 | |
| 7716 | struct block * |
| 7717 | gen_pf_srnr(int srnr) |
| 7718 | { |
| 7719 | bpf_error("libpcap was compiled on a machine without pf support"); |
| 7720 | /* NOTREACHED */ |
| 7721 | return (NULL); |
| 7722 | } |
| 7723 | |
| 7724 | struct block * |
| 7725 | gen_pf_reason(int reason) |
| 7726 | { |
| 7727 | bpf_error("libpcap was compiled on a machine without pf support"); |
| 7728 | /* NOTREACHED */ |
| 7729 | return (NULL); |
| 7730 | } |
| 7731 | |
| 7732 | struct block * |
| 7733 | gen_pf_action(int action) |
| 7734 | { |
| 7735 | bpf_error("libpcap was compiled on a machine without pf support"); |
| 7736 | /* NOTREACHED */ |
| 7737 | return (NULL); |
| 7738 | } |
| 7739 | #endif /* HAVE_NET_PFVAR_H */ |
| 7740 | |
| 7741 | /* IEEE 802.11 wireless header */ |
| 7742 | struct block * |
| 7743 | gen_p80211_type(int type, int mask) |
| 7744 | { |
| 7745 | struct block *b0; |
| 7746 | |
| 7747 | switch (linktype) { |
| 7748 | |
| 7749 | case DLT_IEEE802_11: |
| 7750 | case DLT_PRISM_HEADER: |
| 7751 | case DLT_IEEE802_11_RADIO_AVS: |
| 7752 | case DLT_IEEE802_11_RADIO: |
| 7753 | b0 = gen_mcmp(OR_LINK, 0, BPF_B, (bpf_int32)type, |
| 7754 | (bpf_int32)mask); |
| 7755 | break; |
| 7756 | |
| 7757 | default: |
| 7758 | bpf_error("802.11 link-layer types supported only on 802.11"); |
| 7759 | /* NOTREACHED */ |
| 7760 | } |
| 7761 | |
| 7762 | return (b0); |
| 7763 | } |
| 7764 | |
| 7765 | struct block * |
| 7766 | gen_p80211_fcdir(int fcdir) |
| 7767 | { |
| 7768 | struct block *b0; |
| 7769 | |
| 7770 | switch (linktype) { |
| 7771 | |
| 7772 | case DLT_IEEE802_11: |
| 7773 | case DLT_PRISM_HEADER: |
| 7774 | case DLT_IEEE802_11_RADIO_AVS: |
| 7775 | case DLT_IEEE802_11_RADIO: |
| 7776 | break; |
| 7777 | |
| 7778 | default: |
| 7779 | bpf_error("frame direction supported only with 802.11 headers"); |
| 7780 | /* NOTREACHED */ |
| 7781 | } |
| 7782 | |
| 7783 | b0 = gen_mcmp(OR_LINK, 1, BPF_B, (bpf_int32)fcdir, |
| 7784 | (bpf_u_int32)IEEE80211_FC1_DIR_MASK); |
| 7785 | |
| 7786 | return (b0); |
| 7787 | } |
| 7788 | |
| 7789 | struct block * |
| 7790 | gen_acode(eaddr, q) |
| 7791 | register const u_char *eaddr; |
| 7792 | struct qual q; |
| 7793 | { |
| 7794 | switch (linktype) { |
| 7795 | |
| 7796 | case DLT_ARCNET: |
| 7797 | case DLT_ARCNET_LINUX: |
| 7798 | if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && |
| 7799 | q.proto == Q_LINK) |
| 7800 | return (gen_ahostop(eaddr, (int)q.dir)); |
| 7801 | else { |
| 7802 | bpf_error("ARCnet address used in non-arc expression"); |
| 7803 | /* NOTREACHED */ |
| 7804 | } |
| 7805 | break; |
| 7806 | |
| 7807 | default: |
| 7808 | bpf_error("aid supported only on ARCnet"); |
| 7809 | /* NOTREACHED */ |
| 7810 | } |
| 7811 | bpf_error("ARCnet address used in non-arc expression"); |
| 7812 | /* NOTREACHED */ |
| 7813 | return NULL; |
| 7814 | } |
| 7815 | |
| 7816 | static struct block * |
| 7817 | gen_ahostop(eaddr, dir) |
| 7818 | register const u_char *eaddr; |
| 7819 | register int dir; |
| 7820 | { |
| 7821 | register struct block *b0, *b1; |
| 7822 | |
| 7823 | switch (dir) { |
| 7824 | /* src comes first, different from Ethernet */ |
| 7825 | case Q_SRC: |
| 7826 | return gen_bcmp(OR_LINK, 0, 1, eaddr); |
| 7827 | |
| 7828 | case Q_DST: |
| 7829 | return gen_bcmp(OR_LINK, 1, 1, eaddr); |
| 7830 | |
| 7831 | case Q_AND: |
| 7832 | b0 = gen_ahostop(eaddr, Q_SRC); |
| 7833 | b1 = gen_ahostop(eaddr, Q_DST); |
| 7834 | gen_and(b0, b1); |
| 7835 | return b1; |
| 7836 | |
| 7837 | case Q_DEFAULT: |
| 7838 | case Q_OR: |
| 7839 | b0 = gen_ahostop(eaddr, Q_SRC); |
| 7840 | b1 = gen_ahostop(eaddr, Q_DST); |
| 7841 | gen_or(b0, b1); |
| 7842 | return b1; |
| 7843 | |
| 7844 | case Q_ADDR1: |
| 7845 | bpf_error("'addr1' is only supported on 802.11"); |
| 7846 | break; |
| 7847 | |
| 7848 | case Q_ADDR2: |
| 7849 | bpf_error("'addr2' is only supported on 802.11"); |
| 7850 | break; |
| 7851 | |
| 7852 | case Q_ADDR3: |
| 7853 | bpf_error("'addr3' is only supported on 802.11"); |
| 7854 | break; |
| 7855 | |
| 7856 | case Q_ADDR4: |
| 7857 | bpf_error("'addr4' is only supported on 802.11"); |
| 7858 | break; |
| 7859 | |
| 7860 | case Q_RA: |
| 7861 | bpf_error("'ra' is only supported on 802.11"); |
| 7862 | break; |
| 7863 | |
| 7864 | case Q_TA: |
| 7865 | bpf_error("'ta' is only supported on 802.11"); |
| 7866 | break; |
| 7867 | } |
| 7868 | abort(); |
| 7869 | /* NOTREACHED */ |
| 7870 | } |
| 7871 | |
| 7872 | /* |
| 7873 | * support IEEE 802.1Q VLAN trunk over ethernet |
| 7874 | */ |
| 7875 | struct block * |
| 7876 | gen_vlan(vlan_num) |
| 7877 | int vlan_num; |
| 7878 | { |
| 7879 | struct block *b0, *b1; |
| 7880 | |
| 7881 | /* can't check for VLAN-encapsulated packets inside MPLS */ |
| 7882 | if (label_stack_depth > 0) |
| 7883 | bpf_error("no VLAN match after MPLS"); |
| 7884 | |
| 7885 | /* |
| 7886 | * Check for a VLAN packet, and then change the offsets to point |
| 7887 | * to the type and data fields within the VLAN packet. Just |
| 7888 | * increment the offsets, so that we can support a hierarchy, e.g. |
| 7889 | * "vlan 300 && vlan 200" to capture VLAN 200 encapsulated within |
| 7890 | * VLAN 100. |
| 7891 | * |
| 7892 | * XXX - this is a bit of a kludge. If we were to split the |
| 7893 | * compiler into a parser that parses an expression and |
| 7894 | * generates an expression tree, and a code generator that |
| 7895 | * takes an expression tree (which could come from our |
| 7896 | * parser or from some other parser) and generates BPF code, |
| 7897 | * we could perhaps make the offsets parameters of routines |
| 7898 | * and, in the handler for an "AND" node, pass to subnodes |
| 7899 | * other than the VLAN node the adjusted offsets. |
| 7900 | * |
| 7901 | * This would mean that "vlan" would, instead of changing the |
| 7902 | * behavior of *all* tests after it, change only the behavior |
| 7903 | * of tests ANDed with it. That would change the documented |
| 7904 | * semantics of "vlan", which might break some expressions. |
| 7905 | * However, it would mean that "(vlan and ip) or ip" would check |
| 7906 | * both for VLAN-encapsulated IP and IP-over-Ethernet, rather than |
| 7907 | * checking only for VLAN-encapsulated IP, so that could still |
| 7908 | * be considered worth doing; it wouldn't break expressions |
| 7909 | * that are of the form "vlan and ..." or "vlan N and ...", |
| 7910 | * which I suspect are the most common expressions involving |
| 7911 | * "vlan". "vlan or ..." doesn't necessarily do what the user |
| 7912 | * would really want, now, as all the "or ..." tests would |
| 7913 | * be done assuming a VLAN, even though the "or" could be viewed |
| 7914 | * as meaning "or, if this isn't a VLAN packet...". |
| 7915 | */ |
| 7916 | orig_nl = off_nl; |
| 7917 | |
| 7918 | switch (linktype) { |
| 7919 | |
| 7920 | case DLT_EN10MB: |
| 7921 | case DLT_NETANALYZER: |
| 7922 | case DLT_NETANALYZER_TRANSPARENT: |
| 7923 | /* check for VLAN, including QinQ */ |
| 7924 | b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 7925 | (bpf_int32)ETHERTYPE_8021Q); |
| 7926 | b1 = gen_cmp(OR_LINK, off_linktype, BPF_H, |
| 7927 | (bpf_int32)ETHERTYPE_8021QINQ); |
| 7928 | gen_or(b0,b1); |
| 7929 | b0 = b1; |
| 7930 | |
| 7931 | /* If a specific VLAN is requested, check VLAN id */ |
| 7932 | if (vlan_num >= 0) { |
| 7933 | b1 = gen_mcmp(OR_MACPL, 0, BPF_H, |
| 7934 | (bpf_int32)vlan_num, 0x0fff); |
| 7935 | gen_and(b0, b1); |
| 7936 | b0 = b1; |
| 7937 | } |
| 7938 | |
| 7939 | off_macpl += 4; |
| 7940 | off_linktype += 4; |
| 7941 | #if 0 |
| 7942 | off_nl_nosnap += 4; |
| 7943 | off_nl += 4; |
| 7944 | #endif |
| 7945 | break; |
| 7946 | |
| 7947 | default: |
| 7948 | bpf_error("no VLAN support for data link type %d", |
| 7949 | linktype); |
| 7950 | /*NOTREACHED*/ |
| 7951 | } |
| 7952 | |
| 7953 | return (b0); |
| 7954 | } |
| 7955 | |
| 7956 | /* |
| 7957 | * support for MPLS |
| 7958 | */ |
| 7959 | struct block * |
| 7960 | gen_mpls(label_num) |
| 7961 | int label_num; |
| 7962 | { |
| 7963 | struct block *b0,*b1; |
| 7964 | |
| 7965 | /* |
| 7966 | * Change the offsets to point to the type and data fields within |
| 7967 | * the MPLS packet. Just increment the offsets, so that we |
| 7968 | * can support a hierarchy, e.g. "mpls 100000 && mpls 1024" to |
| 7969 | * capture packets with an outer label of 100000 and an inner |
| 7970 | * label of 1024. |
| 7971 | * |
| 7972 | * XXX - this is a bit of a kludge. See comments in gen_vlan(). |
| 7973 | */ |
| 7974 | orig_nl = off_nl; |
| 7975 | |
| 7976 | if (label_stack_depth > 0) { |
| 7977 | /* just match the bottom-of-stack bit clear */ |
| 7978 | b0 = gen_mcmp(OR_MACPL, orig_nl-2, BPF_B, 0, 0x01); |
| 7979 | } else { |
| 7980 | /* |
| 7981 | * Indicate that we're checking MPLS-encapsulated headers, |
| 7982 | * to make sure higher level code generators don't try to |
| 7983 | * match against IP-related protocols such as Q_ARP, Q_RARP |
| 7984 | * etc. |
| 7985 | */ |
| 7986 | switch (linktype) { |
| 7987 | |
| 7988 | case DLT_C_HDLC: /* fall through */ |
| 7989 | case DLT_EN10MB: |
| 7990 | case DLT_NETANALYZER: |
| 7991 | case DLT_NETANALYZER_TRANSPARENT: |
| 7992 | b0 = gen_linktype(ETHERTYPE_MPLS); |
| 7993 | break; |
| 7994 | |
| 7995 | case DLT_PPP: |
| 7996 | b0 = gen_linktype(PPP_MPLS_UCAST); |
| 7997 | break; |
| 7998 | |
| 7999 | /* FIXME add other DLT_s ... |
| 8000 | * for Frame-Relay/and ATM this may get messy due to SNAP headers |
| 8001 | * leave it for now */ |
| 8002 | |
| 8003 | default: |
| 8004 | bpf_error("no MPLS support for data link type %d", |
| 8005 | linktype); |
| 8006 | b0 = NULL; |
| 8007 | /*NOTREACHED*/ |
| 8008 | break; |
| 8009 | } |
| 8010 | } |
| 8011 | |
| 8012 | /* If a specific MPLS label is requested, check it */ |
| 8013 | if (label_num >= 0) { |
| 8014 | label_num = label_num << 12; /* label is shifted 12 bits on the wire */ |
| 8015 | b1 = gen_mcmp(OR_MACPL, orig_nl, BPF_W, (bpf_int32)label_num, |
| 8016 | 0xfffff000); /* only compare the first 20 bits */ |
| 8017 | gen_and(b0, b1); |
| 8018 | b0 = b1; |
| 8019 | } |
| 8020 | |
| 8021 | off_nl_nosnap += 4; |
| 8022 | off_nl += 4; |
| 8023 | label_stack_depth++; |
| 8024 | return (b0); |
| 8025 | } |
| 8026 | |
| 8027 | /* |
| 8028 | * Support PPPOE discovery and session. |
| 8029 | */ |
| 8030 | struct block * |
| 8031 | gen_pppoed() |
| 8032 | { |
| 8033 | /* check for PPPoE discovery */ |
| 8034 | return gen_linktype((bpf_int32)ETHERTYPE_PPPOED); |
| 8035 | } |
| 8036 | |
| 8037 | struct block * |
| 8038 | gen_pppoes() |
| 8039 | { |
| 8040 | struct block *b0; |
| 8041 | |
| 8042 | /* |
| 8043 | * Test against the PPPoE session link-layer type. |
| 8044 | */ |
| 8045 | b0 = gen_linktype((bpf_int32)ETHERTYPE_PPPOES); |
| 8046 | |
| 8047 | /* |
| 8048 | * Change the offsets to point to the type and data fields within |
| 8049 | * the PPP packet, and note that this is PPPoE rather than |
| 8050 | * raw PPP. |
| 8051 | * |
| 8052 | * XXX - this is a bit of a kludge. If we were to split the |
| 8053 | * compiler into a parser that parses an expression and |
| 8054 | * generates an expression tree, and a code generator that |
| 8055 | * takes an expression tree (which could come from our |
| 8056 | * parser or from some other parser) and generates BPF code, |
| 8057 | * we could perhaps make the offsets parameters of routines |
| 8058 | * and, in the handler for an "AND" node, pass to subnodes |
| 8059 | * other than the PPPoE node the adjusted offsets. |
| 8060 | * |
| 8061 | * This would mean that "pppoes" would, instead of changing the |
| 8062 | * behavior of *all* tests after it, change only the behavior |
| 8063 | * of tests ANDed with it. That would change the documented |
| 8064 | * semantics of "pppoes", which might break some expressions. |
| 8065 | * However, it would mean that "(pppoes and ip) or ip" would check |
| 8066 | * both for VLAN-encapsulated IP and IP-over-Ethernet, rather than |
| 8067 | * checking only for VLAN-encapsulated IP, so that could still |
| 8068 | * be considered worth doing; it wouldn't break expressions |
| 8069 | * that are of the form "pppoes and ..." which I suspect are the |
| 8070 | * most common expressions involving "pppoes". "pppoes or ..." |
| 8071 | * doesn't necessarily do what the user would really want, now, |
| 8072 | * as all the "or ..." tests would be done assuming PPPoE, even |
| 8073 | * though the "or" could be viewed as meaning "or, if this isn't |
| 8074 | * a PPPoE packet...". |
| 8075 | */ |
| 8076 | orig_linktype = off_linktype; /* save original values */ |
| 8077 | orig_nl = off_nl; |
| 8078 | is_pppoes = 1; |
| 8079 | |
| 8080 | /* |
| 8081 | * The "network-layer" protocol is PPPoE, which has a 6-byte |
| 8082 | * PPPoE header, followed by a PPP packet. |
| 8083 | * |
| 8084 | * There is no HDLC encapsulation for the PPP packet (it's |
| 8085 | * encapsulated in PPPoES instead), so the link-layer type |
| 8086 | * starts at the first byte of the PPP packet. For PPPoE, |
| 8087 | * that offset is relative to the beginning of the total |
| 8088 | * link-layer payload, including any 802.2 LLC header, so |
| 8089 | * it's 6 bytes past off_nl. |
| 8090 | */ |
| 8091 | off_linktype = off_nl + 6; |
| 8092 | |
| 8093 | /* |
| 8094 | * The network-layer offsets are relative to the beginning |
| 8095 | * of the MAC-layer payload; that's past the 6-byte |
| 8096 | * PPPoE header and the 2-byte PPP header. |
| 8097 | */ |
| 8098 | off_nl = 6+2; |
| 8099 | off_nl_nosnap = 6+2; |
| 8100 | |
| 8101 | return b0; |
| 8102 | } |
| 8103 | |
| 8104 | struct block * |
| 8105 | gen_atmfield_code(atmfield, jvalue, jtype, reverse) |
| 8106 | int atmfield; |
| 8107 | bpf_int32 jvalue; |
| 8108 | bpf_u_int32 jtype; |
| 8109 | int reverse; |
| 8110 | { |
| 8111 | struct block *b0; |
| 8112 | |
| 8113 | switch (atmfield) { |
| 8114 | |
| 8115 | case A_VPI: |
| 8116 | if (!is_atm) |
| 8117 | bpf_error("'vpi' supported only on raw ATM"); |
| 8118 | if (off_vpi == (u_int)-1) |
| 8119 | abort(); |
| 8120 | b0 = gen_ncmp(OR_LINK, off_vpi, BPF_B, 0xffffffff, jtype, |
| 8121 | reverse, jvalue); |
| 8122 | break; |
| 8123 | |
| 8124 | case A_VCI: |
| 8125 | if (!is_atm) |
| 8126 | bpf_error("'vci' supported only on raw ATM"); |
| 8127 | if (off_vci == (u_int)-1) |
| 8128 | abort(); |
| 8129 | b0 = gen_ncmp(OR_LINK, off_vci, BPF_H, 0xffffffff, jtype, |
| 8130 | reverse, jvalue); |
| 8131 | break; |
| 8132 | |
| 8133 | case A_PROTOTYPE: |
| 8134 | if (off_proto == (u_int)-1) |
| 8135 | abort(); /* XXX - this isn't on FreeBSD */ |
| 8136 | b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0x0f, jtype, |
| 8137 | reverse, jvalue); |
| 8138 | break; |
| 8139 | |
| 8140 | case A_MSGTYPE: |
| 8141 | if (off_payload == (u_int)-1) |
| 8142 | abort(); |
| 8143 | b0 = gen_ncmp(OR_LINK, off_payload + MSG_TYPE_POS, BPF_B, |
| 8144 | 0xffffffff, jtype, reverse, jvalue); |
| 8145 | break; |
| 8146 | |
| 8147 | case A_CALLREFTYPE: |
| 8148 | if (!is_atm) |
| 8149 | bpf_error("'callref' supported only on raw ATM"); |
| 8150 | if (off_proto == (u_int)-1) |
| 8151 | abort(); |
| 8152 | b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0xffffffff, |
| 8153 | jtype, reverse, jvalue); |
| 8154 | break; |
| 8155 | |
| 8156 | default: |
| 8157 | abort(); |
| 8158 | } |
| 8159 | return b0; |
| 8160 | } |
| 8161 | |
| 8162 | struct block * |
| 8163 | gen_atmtype_abbrev(type) |
| 8164 | int type; |
| 8165 | { |
| 8166 | struct block *b0, *b1; |
| 8167 | |
| 8168 | switch (type) { |
| 8169 | |
| 8170 | case A_METAC: |
| 8171 | /* Get all packets in Meta signalling Circuit */ |
| 8172 | if (!is_atm) |
| 8173 | bpf_error("'metac' supported only on raw ATM"); |
| 8174 | b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); |
| 8175 | b1 = gen_atmfield_code(A_VCI, 1, BPF_JEQ, 0); |
| 8176 | gen_and(b0, b1); |
| 8177 | break; |
| 8178 | |
| 8179 | case A_BCC: |
| 8180 | /* Get all packets in Broadcast Circuit*/ |
| 8181 | if (!is_atm) |
| 8182 | bpf_error("'bcc' supported only on raw ATM"); |
| 8183 | b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); |
| 8184 | b1 = gen_atmfield_code(A_VCI, 2, BPF_JEQ, 0); |
| 8185 | gen_and(b0, b1); |
| 8186 | break; |
| 8187 | |
| 8188 | case A_OAMF4SC: |
| 8189 | /* Get all cells in Segment OAM F4 circuit*/ |
| 8190 | if (!is_atm) |
| 8191 | bpf_error("'oam4sc' supported only on raw ATM"); |
| 8192 | b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); |
| 8193 | b1 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0); |
| 8194 | gen_and(b0, b1); |
| 8195 | break; |
| 8196 | |
| 8197 | case A_OAMF4EC: |
| 8198 | /* Get all cells in End-to-End OAM F4 Circuit*/ |
| 8199 | if (!is_atm) |
| 8200 | bpf_error("'oam4ec' supported only on raw ATM"); |
| 8201 | b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); |
| 8202 | b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0); |
| 8203 | gen_and(b0, b1); |
| 8204 | break; |
| 8205 | |
| 8206 | case A_SC: |
| 8207 | /* Get all packets in connection Signalling Circuit */ |
| 8208 | if (!is_atm) |
| 8209 | bpf_error("'sc' supported only on raw ATM"); |
| 8210 | b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); |
| 8211 | b1 = gen_atmfield_code(A_VCI, 5, BPF_JEQ, 0); |
| 8212 | gen_and(b0, b1); |
| 8213 | break; |
| 8214 | |
| 8215 | case A_ILMIC: |
| 8216 | /* Get all packets in ILMI Circuit */ |
| 8217 | if (!is_atm) |
| 8218 | bpf_error("'ilmic' supported only on raw ATM"); |
| 8219 | b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); |
| 8220 | b1 = gen_atmfield_code(A_VCI, 16, BPF_JEQ, 0); |
| 8221 | gen_and(b0, b1); |
| 8222 | break; |
| 8223 | |
| 8224 | case A_LANE: |
| 8225 | /* Get all LANE packets */ |
| 8226 | if (!is_atm) |
| 8227 | bpf_error("'lane' supported only on raw ATM"); |
| 8228 | b1 = gen_atmfield_code(A_PROTOTYPE, PT_LANE, BPF_JEQ, 0); |
| 8229 | |
| 8230 | /* |
| 8231 | * Arrange that all subsequent tests assume LANE |
| 8232 | * rather than LLC-encapsulated packets, and set |
| 8233 | * the offsets appropriately for LANE-encapsulated |
| 8234 | * Ethernet. |
| 8235 | * |
| 8236 | * "off_mac" is the offset of the Ethernet header, |
| 8237 | * which is 2 bytes past the ATM pseudo-header |
| 8238 | * (skipping the pseudo-header and 2-byte LE Client |
| 8239 | * field). The other offsets are Ethernet offsets |
| 8240 | * relative to "off_mac". |
| 8241 | */ |
| 8242 | is_lane = 1; |
| 8243 | off_mac = off_payload + 2; /* MAC header */ |
| 8244 | off_linktype = off_mac + 12; |
| 8245 | off_macpl = off_mac + 14; /* Ethernet */ |
| 8246 | off_nl = 0; /* Ethernet II */ |
| 8247 | off_nl_nosnap = 3; /* 802.3+802.2 */ |
| 8248 | break; |
| 8249 | |
| 8250 | case A_LLC: |
| 8251 | /* Get all LLC-encapsulated packets */ |
| 8252 | if (!is_atm) |
| 8253 | bpf_error("'llc' supported only on raw ATM"); |
| 8254 | b1 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0); |
| 8255 | is_lane = 0; |
| 8256 | break; |
| 8257 | |
| 8258 | default: |
| 8259 | abort(); |
| 8260 | } |
| 8261 | return b1; |
| 8262 | } |
| 8263 | |
| 8264 | /* |
| 8265 | * Filtering for MTP2 messages based on li value |
| 8266 | * FISU, length is null |
| 8267 | * LSSU, length is 1 or 2 |
| 8268 | * MSU, length is 3 or more |
| 8269 | */ |
| 8270 | struct block * |
| 8271 | gen_mtp2type_abbrev(type) |
| 8272 | int type; |
| 8273 | { |
| 8274 | struct block *b0, *b1; |
| 8275 | |
| 8276 | switch (type) { |
| 8277 | |
| 8278 | case M_FISU: |
| 8279 | if ( (linktype != DLT_MTP2) && |
| 8280 | (linktype != DLT_ERF) && |
| 8281 | (linktype != DLT_MTP2_WITH_PHDR) ) |
| 8282 | bpf_error("'fisu' supported only on MTP2"); |
| 8283 | /* gen_ncmp(offrel, offset, size, mask, jtype, reverse, value) */ |
| 8284 | b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JEQ, 0, 0); |
| 8285 | break; |
| 8286 | |
| 8287 | case M_LSSU: |
| 8288 | if ( (linktype != DLT_MTP2) && |
| 8289 | (linktype != DLT_ERF) && |
| 8290 | (linktype != DLT_MTP2_WITH_PHDR) ) |
| 8291 | bpf_error("'lssu' supported only on MTP2"); |
| 8292 | b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 1, 2); |
| 8293 | b1 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 0, 0); |
| 8294 | gen_and(b1, b0); |
| 8295 | break; |
| 8296 | |
| 8297 | case M_MSU: |
| 8298 | if ( (linktype != DLT_MTP2) && |
| 8299 | (linktype != DLT_ERF) && |
| 8300 | (linktype != DLT_MTP2_WITH_PHDR) ) |
| 8301 | bpf_error("'msu' supported only on MTP2"); |
| 8302 | b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 0, 2); |
| 8303 | break; |
| 8304 | |
| 8305 | default: |
| 8306 | abort(); |
| 8307 | } |
| 8308 | return b0; |
| 8309 | } |
| 8310 | |
| 8311 | struct block * |
| 8312 | gen_mtp3field_code(mtp3field, jvalue, jtype, reverse) |
| 8313 | int mtp3field; |
| 8314 | bpf_u_int32 jvalue; |
| 8315 | bpf_u_int32 jtype; |
| 8316 | int reverse; |
| 8317 | { |
| 8318 | struct block *b0; |
| 8319 | bpf_u_int32 val1 , val2 , val3; |
| 8320 | |
| 8321 | switch (mtp3field) { |
| 8322 | |
| 8323 | case M_SIO: |
| 8324 | if (off_sio == (u_int)-1) |
| 8325 | bpf_error("'sio' supported only on SS7"); |
| 8326 | /* sio coded on 1 byte so max value 255 */ |
| 8327 | if(jvalue > 255) |
| 8328 | bpf_error("sio value %u too big; max value = 255", |
| 8329 | jvalue); |
| 8330 | b0 = gen_ncmp(OR_PACKET, off_sio, BPF_B, 0xffffffff, |
| 8331 | (u_int)jtype, reverse, (u_int)jvalue); |
| 8332 | break; |
| 8333 | |
| 8334 | case M_OPC: |
| 8335 | if (off_opc == (u_int)-1) |
| 8336 | bpf_error("'opc' supported only on SS7"); |
| 8337 | /* opc coded on 14 bits so max value 16383 */ |
| 8338 | if (jvalue > 16383) |
| 8339 | bpf_error("opc value %u too big; max value = 16383", |
| 8340 | jvalue); |
| 8341 | /* the following instructions are made to convert jvalue |
| 8342 | * to the form used to write opc in an ss7 message*/ |
| 8343 | val1 = jvalue & 0x00003c00; |
| 8344 | val1 = val1 >>10; |
| 8345 | val2 = jvalue & 0x000003fc; |
| 8346 | val2 = val2 <<6; |
| 8347 | val3 = jvalue & 0x00000003; |
| 8348 | val3 = val3 <<22; |
| 8349 | jvalue = val1 + val2 + val3; |
| 8350 | b0 = gen_ncmp(OR_PACKET, off_opc, BPF_W, 0x00c0ff0f, |
| 8351 | (u_int)jtype, reverse, (u_int)jvalue); |
| 8352 | break; |
| 8353 | |
| 8354 | case M_DPC: |
| 8355 | if (off_dpc == (u_int)-1) |
| 8356 | bpf_error("'dpc' supported only on SS7"); |
| 8357 | /* dpc coded on 14 bits so max value 16383 */ |
| 8358 | if (jvalue > 16383) |
| 8359 | bpf_error("dpc value %u too big; max value = 16383", |
| 8360 | jvalue); |
| 8361 | /* the following instructions are made to convert jvalue |
| 8362 | * to the forme used to write dpc in an ss7 message*/ |
| 8363 | val1 = jvalue & 0x000000ff; |
| 8364 | val1 = val1 << 24; |
| 8365 | val2 = jvalue & 0x00003f00; |
| 8366 | val2 = val2 << 8; |
| 8367 | jvalue = val1 + val2; |
| 8368 | b0 = gen_ncmp(OR_PACKET, off_dpc, BPF_W, 0xff3f0000, |
| 8369 | (u_int)jtype, reverse, (u_int)jvalue); |
| 8370 | break; |
| 8371 | |
| 8372 | case M_SLS: |
| 8373 | if (off_sls == (u_int)-1) |
| 8374 | bpf_error("'sls' supported only on SS7"); |
| 8375 | /* sls coded on 4 bits so max value 15 */ |
| 8376 | if (jvalue > 15) |
| 8377 | bpf_error("sls value %u too big; max value = 15", |
| 8378 | jvalue); |
| 8379 | /* the following instruction is made to convert jvalue |
| 8380 | * to the forme used to write sls in an ss7 message*/ |
| 8381 | jvalue = jvalue << 4; |
| 8382 | b0 = gen_ncmp(OR_PACKET, off_sls, BPF_B, 0xf0, |
| 8383 | (u_int)jtype,reverse, (u_int)jvalue); |
| 8384 | break; |
| 8385 | |
| 8386 | default: |
| 8387 | abort(); |
| 8388 | } |
| 8389 | return b0; |
| 8390 | } |
| 8391 | |
| 8392 | static struct block * |
| 8393 | gen_msg_abbrev(type) |
| 8394 | int type; |
| 8395 | { |
| 8396 | struct block *b1; |
| 8397 | |
| 8398 | /* |
| 8399 | * Q.2931 signalling protocol messages for handling virtual circuits |
| 8400 | * establishment and teardown |
| 8401 | */ |
| 8402 | switch (type) { |
| 8403 | |
| 8404 | case A_SETUP: |
| 8405 | b1 = gen_atmfield_code(A_MSGTYPE, SETUP, BPF_JEQ, 0); |
| 8406 | break; |
| 8407 | |
| 8408 | case A_CALLPROCEED: |
| 8409 | b1 = gen_atmfield_code(A_MSGTYPE, CALL_PROCEED, BPF_JEQ, 0); |
| 8410 | break; |
| 8411 | |
| 8412 | case A_CONNECT: |
| 8413 | b1 = gen_atmfield_code(A_MSGTYPE, CONNECT, BPF_JEQ, 0); |
| 8414 | break; |
| 8415 | |
| 8416 | case A_CONNECTACK: |
| 8417 | b1 = gen_atmfield_code(A_MSGTYPE, CONNECT_ACK, BPF_JEQ, 0); |
| 8418 | break; |
| 8419 | |
| 8420 | case A_RELEASE: |
| 8421 | b1 = gen_atmfield_code(A_MSGTYPE, RELEASE, BPF_JEQ, 0); |
| 8422 | break; |
| 8423 | |
| 8424 | case A_RELEASE_DONE: |
| 8425 | b1 = gen_atmfield_code(A_MSGTYPE, RELEASE_DONE, BPF_JEQ, 0); |
| 8426 | break; |
| 8427 | |
| 8428 | default: |
| 8429 | abort(); |
| 8430 | } |
| 8431 | return b1; |
| 8432 | } |
| 8433 | |
| 8434 | struct block * |
| 8435 | gen_atmmulti_abbrev(type) |
| 8436 | int type; |
| 8437 | { |
| 8438 | struct block *b0, *b1; |
| 8439 | |
| 8440 | switch (type) { |
| 8441 | |
| 8442 | case A_OAM: |
| 8443 | if (!is_atm) |
| 8444 | bpf_error("'oam' supported only on raw ATM"); |
| 8445 | b1 = gen_atmmulti_abbrev(A_OAMF4); |
| 8446 | break; |
| 8447 | |
| 8448 | case A_OAMF4: |
| 8449 | if (!is_atm) |
| 8450 | bpf_error("'oamf4' supported only on raw ATM"); |
| 8451 | /* OAM F4 type */ |
| 8452 | b0 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0); |
| 8453 | b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0); |
| 8454 | gen_or(b0, b1); |
| 8455 | b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0); |
| 8456 | gen_and(b0, b1); |
| 8457 | break; |
| 8458 | |
| 8459 | case A_CONNECTMSG: |
| 8460 | /* |
| 8461 | * Get Q.2931 signalling messages for switched |
| 8462 | * virtual connection |
| 8463 | */ |
| 8464 | if (!is_atm) |
| 8465 | bpf_error("'connectmsg' supported only on raw ATM"); |
| 8466 | b0 = gen_msg_abbrev(A_SETUP); |
| 8467 | b1 = gen_msg_abbrev(A_CALLPROCEED); |
| 8468 | gen_or(b0, b1); |
| 8469 | b0 = gen_msg_abbrev(A_CONNECT); |
| 8470 | gen_or(b0, b1); |
| 8471 | b0 = gen_msg_abbrev(A_CONNECTACK); |
| 8472 | gen_or(b0, b1); |
| 8473 | b0 = gen_msg_abbrev(A_RELEASE); |
| 8474 | gen_or(b0, b1); |
| 8475 | b0 = gen_msg_abbrev(A_RELEASE_DONE); |
| 8476 | gen_or(b0, b1); |
| 8477 | b0 = gen_atmtype_abbrev(A_SC); |
| 8478 | gen_and(b0, b1); |
| 8479 | break; |
| 8480 | |
| 8481 | case A_METACONNECT: |
| 8482 | if (!is_atm) |
| 8483 | bpf_error("'metaconnect' supported only on raw ATM"); |
| 8484 | b0 = gen_msg_abbrev(A_SETUP); |
| 8485 | b1 = gen_msg_abbrev(A_CALLPROCEED); |
| 8486 | gen_or(b0, b1); |
| 8487 | b0 = gen_msg_abbrev(A_CONNECT); |
| 8488 | gen_or(b0, b1); |
| 8489 | b0 = gen_msg_abbrev(A_RELEASE); |
| 8490 | gen_or(b0, b1); |
| 8491 | b0 = gen_msg_abbrev(A_RELEASE_DONE); |
| 8492 | gen_or(b0, b1); |
| 8493 | b0 = gen_atmtype_abbrev(A_METAC); |
| 8494 | gen_and(b0, b1); |
| 8495 | break; |
| 8496 | |
| 8497 | default: |
| 8498 | abort(); |
| 8499 | } |
| 8500 | return b1; |
| 8501 | } |