1 /*#define CHASE_CHAIN*/
3 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998
4 * The Regents of the University of California. All rights reserved.
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
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.
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)";
32 #include <pcap-stdinc.h>
39 #ifdef HAVE_SYS_BITYPES_H
40 #include <sys/bitypes.h>
42 #include <sys/types.h>
43 #include <sys/socket.h>
47 * XXX - why was this included even on UNIX?
56 #include <sys/param.h>
59 #include <netinet/in.h>
60 #include <arpa/inet.h>
76 #include "ethertype.h"
80 #include "ieee80211.h"
82 #include "sunatmpos.h"
85 #include "pcap/ipnet.h"
87 #ifdef HAVE_NET_PFVAR_H
88 #include <sys/socket.h>
90 #include <net/pf/pfvar.h>
91 #include <net/pf/if_pflog.h>
94 #define offsetof(s, e) ((size_t)&((s *)0)->e)
98 #include <netdb.h> /* for "struct addrinfo" */
101 #include <pcap/namedb.h>
103 #define ETHERMTU 1500
106 #define IPPROTO_SCTP 132
109 #ifdef HAVE_OS_PROTO_H
110 #include "os-proto.h"
113 #define JMP(c) ((c)|BPF_JMP|BPF_K)
116 static jmp_buf top_ctx;
117 static pcap_t *bpf_pcap;
119 /* Hack for updating VLAN, MPLS, and PPPoE offsets. */
121 static u_int orig_linktype = (u_int)-1, orig_nl = (u_int)-1, label_stack_depth = (u_int)-1;
123 static u_int orig_linktype = -1U, orig_nl = -1U, label_stack_depth = -1U;
128 static int pcap_fddipad;
133 bpf_error(const char *fmt, ...)
138 if (bpf_pcap != NULL)
139 (void)vsnprintf(pcap_geterr(bpf_pcap), PCAP_ERRBUF_SIZE,
146 static void init_linktype(pcap_t *);
148 static void init_regs(void);
149 static int alloc_reg(void);
150 static void free_reg(int);
152 static struct block *root;
155 * Value passed to gen_load_a() to indicate what the offset argument
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 */
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.
176 static struct addrinfo *ai;
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.
185 * XXX - this *is* in a library....
188 #define CHUNK0SIZE 1024
194 static struct chunk chunks[NCHUNKS];
195 static int cur_chunk;
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);
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,
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);
239 static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int);
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);
251 static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int, int);
254 static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int);
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);
260 static struct block *gen_portatom6(int, bpf_int32);
261 static struct block *gen_portrangeatom6(int, bpf_int32, bpf_int32);
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);
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);
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);
282 static struct block *gen_ppi_dlt_check(void);
283 static struct block *gen_msg_abbrev(int type);
294 /* XXX Round up to nearest long. */
295 n = (n + sizeof(long) - 1) & ~(sizeof(long) - 1);
297 /* XXX Round up to structure boundary. */
301 cp = &chunks[cur_chunk];
302 if (n > cp->n_left) {
303 ++cp, k = ++cur_chunk;
305 bpf_error("out of memory");
306 size = CHUNK0SIZE << k;
307 cp->m = (void *)malloc(size);
309 bpf_error("out of memory");
310 memset((char *)cp->m, 0, size);
313 bpf_error("out of memory");
316 return (void *)((char *)cp->m + cp->n_left);
325 for (i = 0; i < NCHUNKS; ++i)
326 if (chunks[i].m != NULL) {
333 * A strdup whose allocations are freed after code generation is over.
337 register const char *s;
339 int n = strlen(s) + 1;
340 char *cp = newchunk(n);
346 static inline struct block *
352 p = (struct block *)newchunk(sizeof(*p));
359 static inline struct slist *
365 p = (struct slist *)newchunk(sizeof(*p));
371 static struct block *
375 struct block *b = new_block(BPF_RET|BPF_K);
384 bpf_error("syntax error in filter expression");
387 static bpf_u_int32 netmask;
392 pcap_compile_unsafe(pcap_t *p, struct bpf_program *program,
393 const char *buf, int optimize, bpf_u_int32 mask);
396 pcap_compile(pcap_t *p, struct bpf_program *program,
397 const char *buf, int optimize, bpf_u_int32 mask)
401 EnterCriticalSection(&g_PcapCompileCriticalSection);
403 result = pcap_compile_unsafe(p, program, buf, optimize, mask);
405 LeaveCriticalSection(&g_PcapCompileCriticalSection);
411 pcap_compile_unsafe(pcap_t *p, struct bpf_program *program,
412 const char *buf, int optimize, bpf_u_int32 mask)
415 pcap_compile(pcap_t *p, struct bpf_program *program,
416 const char *buf, int optimize, bpf_u_int32 mask)
420 const char * volatile xbuf = buf;
428 if (setjmp(top_ctx)) {
442 snaplen = pcap_snapshot(p);
444 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
445 "snaplen of 0 rejects all packets");
449 lex_init(xbuf ? xbuf : "");
457 root = gen_retblk(snaplen);
459 if (optimize && !no_optimize) {
462 (root->s.code == (BPF_RET|BPF_K) && root->s.k == 0))
463 bpf_error("expression rejects all packets");
465 program->bf_insns = icode_to_fcode(root, &len);
466 program->bf_len = len;
474 * entry point for using the compiler with no pcap open
475 * pass in all the stuff that is needed explicitly instead.
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)
485 p = pcap_open_dead(linktype_arg, snaplen_arg);
488 ret = pcap_compile(p, program, buf, optimize, mask);
494 * Clean up a "struct bpf_program" by freeing all the memory allocated
498 pcap_freecode(struct bpf_program *program)
501 if (program->bf_insns != NULL) {
502 free((char *)program->bf_insns);
503 program->bf_insns = NULL;
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.
514 backpatch(list, target)
515 struct block *list, *target;
532 * Merge the lists in b0 and b1, using the 'sense' field to indicate
533 * which of jt and jf is the link.
537 struct block *b0, *b1;
539 register struct block **p = &b0;
541 /* Find end of list. */
543 p = !((*p)->sense) ? &JT(*p) : &JF(*p);
545 /* Concatenate the lists. */
553 struct block *ppi_dlt_check;
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.
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.
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
574 insert_compute_vloffsets(p->head);
577 * For DLT_PPI captures, generate a check of the per-packet
578 * DLT value to make sure it's DLT_IEEE802_11.
580 ppi_dlt_check = gen_ppi_dlt_check();
581 if (ppi_dlt_check != NULL)
582 gen_and(ppi_dlt_check, p);
584 backpatch(p, gen_retblk(snaplen));
585 p->sense = !p->sense;
586 backpatch(p, gen_retblk(0));
592 struct block *b0, *b1;
594 backpatch(b0, b1->head);
595 b0->sense = !b0->sense;
596 b1->sense = !b1->sense;
598 b1->sense = !b1->sense;
604 struct block *b0, *b1;
606 b0->sense = !b0->sense;
607 backpatch(b0, b1->head);
608 b0->sense = !b0->sense;
617 b->sense = !b->sense;
620 static struct block *
621 gen_cmp(offrel, offset, size, v)
622 enum e_offrel offrel;
626 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JEQ, 0, v);
629 static struct block *
630 gen_cmp_gt(offrel, offset, size, v)
631 enum e_offrel offrel;
635 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 0, v);
638 static struct block *
639 gen_cmp_ge(offrel, offset, size, v)
640 enum e_offrel offrel;
644 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 0, v);
647 static struct block *
648 gen_cmp_lt(offrel, offset, size, v)
649 enum e_offrel offrel;
653 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 1, v);
656 static struct block *
657 gen_cmp_le(offrel, offset, size, v)
658 enum e_offrel offrel;
662 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 1, v);
665 static struct block *
666 gen_mcmp(offrel, offset, size, v, mask)
667 enum e_offrel offrel;
672 return gen_ncmp(offrel, offset, size, mask, BPF_JEQ, 0, v);
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;
681 register struct block *b, *tmp;
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];
689 tmp = gen_cmp(offrel, offset + size - 4, BPF_W, w);
696 register const u_char *p = &v[size - 2];
697 bpf_int32 w = ((bpf_int32)p[0] << 8) | p[1];
699 tmp = gen_cmp(offrel, offset + size - 2, BPF_H, w);
706 tmp = gen_cmp(offrel, offset, BPF_B, (bpf_int32)v[0]);
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".
720 static struct block *
721 gen_ncmp(offrel, offset, size, mask, jtype, reverse, v)
722 enum e_offrel offrel;
724 bpf_u_int32 offset, size, mask, jtype;
727 struct slist *s, *s2;
730 s = gen_load_a(offrel, offset, size);
732 if (mask != 0xffffffff) {
733 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
738 b = new_block(JMP(jtype));
741 if (reverse && (jtype == BPF_JGT || jtype == BPF_JGE))
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.
753 * This is the offset of the beginning of the link-layer header from
754 * the beginning of the raw packet data.
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.)
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.
769 static int reg_off_ll;
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.
778 static u_int off_mac;
781 * This is the offset of the beginning of the MAC-layer payload,
782 * from the beginning of the raw packet data.
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
789 static u_int off_macpl;
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.
795 static int off_macpl_is_variable;
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"
804 static int reg_off_macpl;
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).
811 * For Ethernet, it's the offset of the Ethernet type field.
813 * For link-layer types that always use 802.2 headers, it's the
814 * offset of the LLC header.
816 * For PPP, it's the offset of the PPP type field.
818 * For Cisco HDLC, it's the offset of the CHDLC type field.
820 * For BSD loopback, it's the offset of the AF_ value.
822 * For Linux cooked sockets, it's the offset of the type field.
824 * It's set to -1 for no encapsulation, in which case, IP is assumed.
826 static u_int off_linktype;
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.
833 static int is_pppoes = 0;
836 * TRUE if the link layer includes an ATM pseudo-header.
838 static int is_atm = 0;
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.
844 static int is_lane = 0;
847 * These are offsets for the ATM pseudo-header.
849 static u_int off_vpi;
850 static u_int off_vci;
851 static u_int off_proto;
854 * These are offsets for the MTP2 fields.
859 * These are offsets for the MTP3 fields.
861 static u_int off_sio;
862 static u_int off_opc;
863 static u_int off_dpc;
864 static u_int off_sls;
867 * This is the offset of the first byte after the ATM pseudo_header,
868 * or -1 if there is no ATM pseudo-header.
870 static u_int off_payload;
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).
877 * If the link layer never uses 802.2 LLC:
879 * "off_nl" and "off_nl_nosnap" are the same.
881 * If the link layer always uses 802.2 LLC:
883 * "off_nl" is the offset if there's a SNAP header following
886 * "off_nl_nosnap" is the offset if there's no SNAP header.
888 * If the link layer is Ethernet:
890 * "off_nl" is the offset if the packet is an Ethernet II packet
891 * (we assume no 802.3+802.2+SNAP);
893 * "off_nl_nosnap" is the offset if the packet is an 802.3 packet
894 * with an 802.2 header following it.
897 static u_int off_nl_nosnap;
905 linktype = pcap_datalink(p);
907 pcap_fddipad = p->fddipad;
911 * Assume it's not raw ATM with a pseudo-header, for now.
922 * And that we're not doing PPPoE.
927 * And assume we're not doing SS7.
936 * Also assume it's not 802.11.
940 off_macpl_is_variable = 0;
944 label_stack_depth = 0;
954 off_nl = 0; /* XXX in reality, variable! */
955 off_nl_nosnap = 0; /* no 802.2 LLC */
958 case DLT_ARCNET_LINUX:
961 off_nl = 0; /* XXX in reality, variable! */
962 off_nl_nosnap = 0; /* no 802.2 LLC */
967 off_macpl = 14; /* Ethernet header length */
968 off_nl = 0; /* Ethernet II */
969 off_nl_nosnap = 3; /* 802.3+802.2 */
974 * SLIP doesn't have a link level type. The 16 byte
975 * header is hacked into our SLIP driver.
980 off_nl_nosnap = 0; /* no 802.2 LLC */
984 /* XXX this may be the same as the DLT_PPP_BSDOS case */
989 off_nl_nosnap = 0; /* no 802.2 LLC */
997 off_nl_nosnap = 0; /* no 802.2 LLC */
1004 off_nl_nosnap = 0; /* no 802.2 LLC */
1009 case DLT_C_HDLC: /* BSD/OS Cisco HDLC */
1010 case DLT_PPP_SERIAL: /* NetBSD sync/async serial PPP */
1014 off_nl_nosnap = 0; /* no 802.2 LLC */
1019 * This does no include the Ethernet header, and
1020 * only covers session state.
1025 off_nl_nosnap = 0; /* no 802.2 LLC */
1032 off_nl_nosnap = 0; /* no 802.2 LLC */
1037 * FDDI doesn't really have a link-level type field.
1038 * We set "off_linktype" to the offset of the LLC header.
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?
1046 off_linktype += pcap_fddipad;
1048 off_macpl = 13; /* FDDI MAC header length */
1050 off_macpl += pcap_fddipad;
1052 off_nl = 8; /* 802.2+SNAP */
1053 off_nl_nosnap = 3; /* 802.2 */
1058 * Token Ring doesn't really have a link-level type field.
1059 * We set "off_linktype" to the offset of the LLC header.
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?
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.
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).
1081 off_macpl = 14; /* Token Ring MAC header length */
1082 off_nl = 8; /* 802.2+SNAP */
1083 off_nl_nosnap = 3; /* 802.2 */
1086 case DLT_IEEE802_11:
1087 case DLT_PRISM_HEADER:
1088 case DLT_IEEE802_11_RADIO_AVS:
1089 case DLT_IEEE802_11_RADIO:
1091 * 802.11 doesn't really have a link-level type field.
1092 * We set "off_linktype" to the offset of the LLC header.
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?
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
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 */
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.
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 */
1131 case DLT_ATM_RFC1483:
1132 case DLT_ATM_CLIP: /* Linux ATM defines this */
1134 * assume routed, non-ISO PDUs
1135 * (i.e., LLC = 0xAA-AA-03, OUT = 0x00-00-00)
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....
1145 off_macpl = 0; /* packet begins with LLC header */
1146 off_nl = 8; /* 802.2+SNAP */
1147 off_nl_nosnap = 3; /* 802.2 */
1152 * Full Frontal ATM; you get AALn PDUs with an ATM
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 */
1173 off_nl_nosnap = 0; /* no 802.2 LLC */
1176 case DLT_LINUX_SLL: /* fake header for Linux cooked socket */
1180 off_nl_nosnap = 0; /* no 802.2 LLC */
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.
1192 off_nl_nosnap = 0; /* no 802.2 LLC */
1195 case DLT_IP_OVER_FC:
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.
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.
1208 off_nl = 8; /* 802.2+SNAP */
1209 off_nl_nosnap = 3; /* 802.2 */
1214 * XXX - we should set this to handle SNAP-encapsulated
1215 * frames (NLPID of 0x80).
1220 off_nl_nosnap = 0; /* no 802.2 LLC */
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);
1232 off_nl_nosnap = 0; /* XXX - for now -> no 802.2 LLC */
1235 case DLT_APPLE_IP_OVER_IEEE1394:
1239 off_nl_nosnap = 0; /* no 802.2 LLC */
1242 case DLT_SYMANTEC_FIREWALL:
1245 off_nl = 0; /* Ethernet II */
1246 off_nl_nosnap = 0; /* XXX - what does it do with 802.3 packets? */
1249 #ifdef HAVE_NET_PFVAR_H
1252 off_macpl = PFLOG_HDRLEN;
1254 off_nl_nosnap = 0; /* no 802.2 LLC */
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:
1267 off_nl_nosnap = -1; /* no 802.2 LLC */
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 */
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 */
1284 /* frames captured on a Juniper PPPoE service PIC
1285 * contain raw ethernet frames */
1286 case DLT_JUNIPER_PPPOE:
1287 case DLT_JUNIPER_ETHER:
1290 off_nl = 18; /* Ethernet II */
1291 off_nl_nosnap = 21; /* 802.3+802.2 */
1294 case DLT_JUNIPER_PPPOE_ATM:
1298 off_nl_nosnap = -1; /* no 802.2 LLC */
1301 case DLT_JUNIPER_GGSN:
1305 off_nl_nosnap = -1; /* no 802.2 LLC */
1308 case DLT_JUNIPER_ES:
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 */
1315 case DLT_JUNIPER_MONITOR:
1318 off_nl = 0; /* raw IP/IP6 header */
1319 off_nl_nosnap = -1; /* no 802.2 LLC */
1322 case DLT_JUNIPER_SERVICES:
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 */
1329 case DLT_JUNIPER_VP:
1336 case DLT_JUNIPER_ST:
1343 case DLT_JUNIPER_ISM:
1350 case DLT_JUNIPER_VS:
1351 case DLT_JUNIPER_SRX_E2E:
1352 case DLT_JUNIPER_FIBRECHANNEL:
1353 case DLT_JUNIPER_ATM_CEMIC:
1372 case DLT_MTP2_WITH_PHDR:
1407 * Currently, only raw "link[N:M]" filtering is supported.
1409 off_linktype = -1; /* variable, min 15, max 71 steps of 7 */
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 */
1418 off_macpl = 24; /* ipnet header length */
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 */
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 */
1441 * For values in the range in which we've assigned new
1442 * DLT_ values, only raw "link[N:M]" filtering is supported.
1444 if (linktype >= DLT_MATCHING_MIN &&
1445 linktype <= DLT_MATCHING_MAX) {
1454 bpf_error("unknown data link type %d", linktype);
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.
1464 static struct slist *
1465 gen_load_llrel(offset, size)
1468 struct slist *s, *s2;
1470 s = gen_llprefixlen();
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
1477 * Otherwise, the length of the prefix preceding the link-layer
1478 * header is "off_ll".
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.
1487 s2 = new_stmt(BPF_LD|BPF_IND|size);
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.
1497 s = new_stmt(BPF_LD|BPF_ABS|size);
1498 s->s.k = offset + off_ll;
1504 * Load a value relative to the beginning of the MAC-layer payload.
1506 static struct slist *
1507 gen_load_macplrel(offset, size)
1510 struct slist *s, *s2;
1512 s = gen_off_macpl();
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.
1519 * Otherwise, the offset of the MAC-layer payload is constant,
1520 * and is in off_macpl.
1524 * The offset of the MAC-layer payload is in the X
1525 * register. Do an indirect load, to use the X register
1528 s2 = new_stmt(BPF_LD|BPF_IND|size);
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.
1537 s = new_stmt(BPF_LD|BPF_ABS|size);
1538 s->s.k = off_macpl + offset;
1544 * Load a value relative to the beginning of the specified header.
1546 static struct slist *
1547 gen_load_a(offrel, offset, size)
1548 enum e_offrel offrel;
1551 struct slist *s, *s2;
1556 s = new_stmt(BPF_LD|BPF_ABS|size);
1561 s = gen_load_llrel(offset, size);
1565 s = gen_load_macplrel(offset, size);
1569 s = gen_load_macplrel(off_nl + offset, size);
1573 s = gen_load_macplrel(off_nl_nosnap + offset, size);
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.
1583 s = gen_loadx_iphdrlen();
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}.
1591 * (If the offset of the MAC-layer payload is variable,
1592 * it's included in the value in the X register, and
1595 s2 = new_stmt(BPF_LD|BPF_IND|size);
1596 s2->s.k = off_macpl + off_nl + offset;
1601 s = gen_load_macplrel(off_nl + 40 + offset, size);
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
1616 static struct slist *
1617 gen_loadx_iphdrlen()
1619 struct slist *s, *s2;
1621 s = gen_off_macpl();
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
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.
1635 s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
1638 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
1641 s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
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.
1651 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
1652 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
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
1663 s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
1664 s->s.k = off_macpl + off_nl;
1669 static struct block *
1676 s = new_stmt(BPF_LD|BPF_IMM);
1678 b = new_block(JMP(BPF_JEQ));
1684 static inline struct block *
1687 return gen_uncond(1);
1690 static inline struct block *
1693 return gen_uncond(0);
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.)
1701 #define SWAPLONG(y) \
1702 ((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
1705 * Generate code to match a particular packet type.
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.
1713 static struct block *
1714 gen_ether_linktype(proto)
1717 struct block *b0, *b1;
1723 case LLCSAP_NETBEUI:
1725 * OSI protocols and NetBEUI always use 802.2 encapsulation,
1726 * so we check the DSAP and SSAP.
1728 * LLCSAP_IP checks for IP-over-802.2, rather
1729 * than IP-over-Ethernet or IP-over-SNAP.
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)?
1736 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1738 b1 = gen_cmp(OR_MACPL, 0, BPF_H, (bpf_int32)
1739 ((proto << 8) | proto));
1747 * Ethernet_II frames, which are Ethernet
1748 * frames with a frame type of ETHERTYPE_IPX;
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
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
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.
1768 * XXX - should we generate the same code both
1769 * for tests for LLCSAP_IPX and for ETHERTYPE_IPX?
1773 * This generates code to check both for the
1774 * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3.
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);
1781 * Now we add code to check for SNAP frames with
1782 * ETHERTYPE_IPX, i.e. Ethernet_SNAP.
1784 b0 = gen_snap(0x000000, ETHERTYPE_IPX);
1788 * Now we generate code to check for 802.3
1789 * frames in general.
1791 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
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.
1803 * Now add the check for Ethernet_II frames, and
1804 * do that before checking for the other frame
1807 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1808 (bpf_int32)ETHERTYPE_IPX);
1812 case ETHERTYPE_ATALK:
1813 case ETHERTYPE_AARP:
1815 * EtherTalk (AppleTalk protocols on Ethernet link
1816 * layer) may use 802.2 encapsulation.
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.
1824 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
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).
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).
1838 if (proto == ETHERTYPE_ATALK)
1839 b1 = gen_snap(0x080007, ETHERTYPE_ATALK);
1840 else /* proto == ETHERTYPE_AARP */
1841 b1 = gen_snap(0x000000, ETHERTYPE_AARP);
1845 * Check for Ethernet encapsulation (Ethertalk
1846 * phase 1?); we just check for the Ethernet
1849 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
1855 if (proto <= ETHERMTU) {
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.
1864 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1866 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
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).
1880 return gen_cmp(OR_LINK, off_linktype, BPF_H,
1887 * "proto" is an Ethernet type value and for IPNET, if it is not IPv4
1888 * or IPv6 then we have an error.
1890 static struct block *
1891 gen_ipnet_linktype(proto)
1897 return gen_cmp(OR_LINK, off_linktype, BPF_B,
1898 (bpf_int32)IPH_AF_INET);
1901 case ETHERTYPE_IPV6:
1902 return gen_cmp(OR_LINK, off_linktype, BPF_B,
1903 (bpf_int32)IPH_AF_INET6);
1914 * Generate code to match a particular packet type.
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.
1921 static struct block *
1922 gen_linux_sll_linktype(proto)
1925 struct block *b0, *b1;
1931 case LLCSAP_NETBEUI:
1933 * OSI protocols and NetBEUI always use 802.2 encapsulation,
1934 * so we check the DSAP and SSAP.
1936 * LLCSAP_IP checks for IP-over-802.2, rather
1937 * than IP-over-Ethernet or IP-over-SNAP.
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)?
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));
1952 * Ethernet_II frames, which are Ethernet
1953 * frames with a frame type of ETHERTYPE_IPX;
1955 * Ethernet_802.3 frames, which have a frame
1956 * type of LINUX_SLL_P_802_3;
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
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.
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
1976 b0 = gen_cmp(OR_MACPL, 0, BPF_B, (bpf_int32)LLCSAP_IPX);
1977 b1 = gen_snap(0x000000, ETHERTYPE_IPX);
1979 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
1983 * Now check for 802.3 frames and OR that with
1984 * the previous test.
1986 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_3);
1990 * Now add the check for Ethernet_II frames, and
1991 * do that before checking for the other frame
1994 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1995 (bpf_int32)ETHERTYPE_IPX);
1999 case ETHERTYPE_ATALK:
2000 case ETHERTYPE_AARP:
2002 * EtherTalk (AppleTalk protocols on Ethernet link
2003 * layer) may use 802.2 encapsulation.
2007 * Check for 802.2 encapsulation (EtherTalk phase 2?);
2008 * we check for the 802.2 protocol type in the
2009 * "Ethernet type" field.
2011 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
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).
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).
2024 if (proto == ETHERTYPE_ATALK)
2025 b1 = gen_snap(0x080007, ETHERTYPE_ATALK);
2026 else /* proto == ETHERTYPE_AARP */
2027 b1 = gen_snap(0x000000, ETHERTYPE_AARP);
2031 * Check for Ethernet encapsulation (Ethertalk
2032 * phase 1?); we just check for the Ethernet
2035 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
2041 if (proto <= ETHERMTU) {
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.
2049 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
2051 b1 = gen_cmp(OR_LINK, off_macpl, BPF_B,
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).
2065 return gen_cmp(OR_LINK, off_linktype, BPF_H,
2071 static struct slist *
2072 gen_load_prism_llprefixlen()
2074 struct slist *s1, *s2;
2075 struct slist *sjeq_avs_cookie;
2076 struct slist *sjcommon;
2079 * This code is not compatible with the optimizer, as
2080 * we are generating jmp instructions within a normal
2081 * slist of instructions
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
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.
2100 * XXX - the Prism header is also, in theory, variable-length,
2101 * but no known software generates headers that aren't 144
2104 if (reg_off_ll != -1) {
2108 s1 = new_stmt(BPF_LD|BPF_W|BPF_ABS);
2112 * AND it with 0xFFFFF000.
2114 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
2115 s2->s.k = 0xFFFFF000;
2119 * Compare with 0x80211000.
2121 sjeq_avs_cookie = new_stmt(JMP(BPF_JEQ));
2122 sjeq_avs_cookie->s.k = 0x80211000;
2123 sappend(s1, sjeq_avs_cookie);
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.
2132 s2 = new_stmt(BPF_LD|BPF_W|BPF_ABS);
2135 sjeq_avs_cookie->s.jt = s2;
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.)
2145 sjcommon = new_stmt(JMP(BPF_JA));
2147 sappend(s1, sjcommon);
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.
2155 s2 = new_stmt(BPF_LD|BPF_W|BPF_IMM);
2158 sjeq_avs_cookie->s.jf = s2;
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.
2165 s2 = new_stmt(BPF_ST);
2166 s2->s.k = reg_off_ll;
2168 sjcommon->s.jf = s2;
2171 * Now move it into the X register.
2173 s2 = new_stmt(BPF_MISC|BPF_TAX);
2181 static struct slist *
2182 gen_load_avs_llprefixlen()
2184 struct slist *s1, *s2;
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
2193 if (reg_off_ll != -1) {
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.
2199 s1 = new_stmt(BPF_LD|BPF_W|BPF_ABS);
2203 * Now allocate a register to hold that value and store
2206 s2 = new_stmt(BPF_ST);
2207 s2->s.k = reg_off_ll;
2211 * Now move it into the X register.
2213 s2 = new_stmt(BPF_MISC|BPF_TAX);
2221 static struct slist *
2222 gen_load_radiotap_llprefixlen()
2224 struct slist *s1, *s2;
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
2233 if (reg_off_ll != -1) {
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.
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.
2245 s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
2247 s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
2250 s2 = new_stmt(BPF_MISC|BPF_TAX);
2254 * Load the next byte, at an offset of 2, and OR the
2255 * value from the X register into it.
2257 s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
2260 s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
2264 * Now allocate a register to hold that value and store
2267 s2 = new_stmt(BPF_ST);
2268 s2->s.k = reg_off_ll;
2272 * Now move it into the X register.
2274 s2 = new_stmt(BPF_MISC|BPF_TAX);
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().
2291 static struct slist *
2292 gen_load_ppi_llprefixlen()
2294 struct slist *s1, *s2;
2297 * Generate code to load the length of the radiotap header
2298 * into the register assigned to hold that length, if one has
2301 if (reg_off_ll != -1) {
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.
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.
2313 s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
2315 s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
2318 s2 = new_stmt(BPF_MISC|BPF_TAX);
2322 * Load the next byte, at an offset of 2, and OR the
2323 * value from the X register into it.
2325 s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
2328 s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
2332 * Now allocate a register to hold that value and store
2335 s2 = new_stmt(BPF_ST);
2336 s2->s.k = reg_off_ll;
2340 * Now move it into the X register.
2342 s2 = new_stmt(BPF_MISC|BPF_TAX);
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.
2357 static struct slist *
2358 gen_load_802_11_header_len(struct slist *s, struct slist *snext)
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;
2369 if (reg_off_macpl == -1) {
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.
2380 * This code is not compatible with the optimizer, as
2381 * we are generating jmp instructions within a normal
2382 * slist of instructions
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
2391 * Otherwise, the length of the prefix preceding the link-layer
2392 * header is "off_ll".
2396 * There is no variable-length header preceding the
2397 * link-layer header.
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.
2404 s = new_stmt(BPF_LDX|BPF_IMM);
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.
2415 s2 = new_stmt(BPF_MISC|BPF_TXA);
2417 s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
2420 s2 = new_stmt(BPF_ST);
2421 s2->s.k = reg_off_macpl;
2424 s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
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.
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);
2438 * If b3 is set, test b2, otherwise go to the first statement of
2439 * the rest of the program.
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;
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
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);
2457 * If it's set, add 2 to reg_off_macpl, to skip the QoS
2459 * Otherwise, go to the first statement of the rest of the
2462 sjset_qos->s.jt = s2 = new_stmt(BPF_LD|BPF_MEM);
2463 s2->s.k = reg_off_macpl;
2465 s2 = new_stmt(BPF_ALU|BPF_ADD|BPF_IMM);
2468 s2 = new_stmt(BPF_ST);
2469 s2->s.k = reg_off_macpl;
2473 * If we have a radiotap header, look at it to see whether
2474 * there's Atheros padding between the MAC-layer header
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
2482 if (linktype == DLT_IEEE802_11_RADIO) {
2484 * Is the IEEE80211_RADIOTAP_FLAGS bit (0x0000002) set
2485 * in the presence flag?
2487 sjset_qos->s.jf = s2 = new_stmt(BPF_LD|BPF_ABS|BPF_W);
2491 sjset_radiotap_flags = new_stmt(JMP(BPF_JSET));
2492 sjset_radiotap_flags->s.k = SWAPLONG(0x00000002);
2493 sappend(s, sjset_radiotap_flags);
2496 * If not, skip all of this.
2498 sjset_radiotap_flags->s.jf = snext;
2501 * Otherwise, is the IEEE80211_RADIOTAP_TSFT bit set?
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);
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
2514 * Test whether the IEEE80211_RADIOTAP_F_DATAPAD bit (0x20)
2517 sjset_radiotap_tsft->s.jt = s2 = new_stmt(BPF_LD|BPF_ABS|BPF_B);
2521 sjset_tsft_datapad = new_stmt(JMP(BPF_JSET));
2522 sjset_tsft_datapad->s.k = 0x20;
2523 sappend(s, sjset_tsft_datapad);
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).
2530 * Test whether the IEEE80211_RADIOTAP_F_DATAPAD bit (0x20)
2533 sjset_radiotap_tsft->s.jf = s2 = new_stmt(BPF_LD|BPF_ABS|BPF_B);
2537 sjset_notsft_datapad = new_stmt(JMP(BPF_JSET));
2538 sjset_notsft_datapad->s.k = 0x20;
2539 sappend(s, sjset_notsft_datapad);
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
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);
2554 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_IMM);
2557 s2 = new_stmt(BPF_ST);
2558 s2->s.k = reg_off_macpl;
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;
2566 sjset_qos->s.jf = snext;
2572 insert_compute_vloffsets(b)
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.
2585 case DLT_PRISM_HEADER:
2586 s = gen_load_prism_llprefixlen();
2589 case DLT_IEEE802_11_RADIO_AVS:
2590 s = gen_load_avs_llprefixlen();
2593 case DLT_IEEE802_11_RADIO:
2594 s = gen_load_radiotap_llprefixlen();
2598 s = gen_load_ppi_llprefixlen();
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.
2613 case DLT_IEEE802_11:
2614 case DLT_PRISM_HEADER:
2615 case DLT_IEEE802_11_RADIO_AVS:
2616 case DLT_IEEE802_11_RADIO:
2618 s = gen_load_802_11_header_len(s, b->stmts);
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
2629 sappend(s, b->stmts);
2634 static struct block *
2635 gen_ppi_dlt_check(void)
2637 struct slist *s_load_dlt;
2640 if (linktype == DLT_PPI)
2642 /* Create the statements that check for the DLT
2644 s_load_dlt = new_stmt(BPF_LD|BPF_W|BPF_ABS);
2645 s_load_dlt->s.k = 4;
2647 b = new_block(JMP(BPF_JEQ));
2649 b->stmts = s_load_dlt;
2650 b->s.k = SWAPLONG(DLT_IEEE802_11);
2660 static struct slist *
2661 gen_prism_llprefixlen(void)
2665 if (reg_off_ll == -1) {
2667 * We haven't yet assigned a register for the length
2668 * of the radio header; allocate one.
2670 reg_off_ll = alloc_reg();
2674 * Load the register containing the radio length
2675 * into the X register.
2677 s = new_stmt(BPF_LDX|BPF_MEM);
2678 s->s.k = reg_off_ll;
2682 static struct slist *
2683 gen_avs_llprefixlen(void)
2687 if (reg_off_ll == -1) {
2689 * We haven't yet assigned a register for the length
2690 * of the AVS header; allocate one.
2692 reg_off_ll = alloc_reg();
2696 * Load the register containing the AVS length
2697 * into the X register.
2699 s = new_stmt(BPF_LDX|BPF_MEM);
2700 s->s.k = reg_off_ll;
2704 static struct slist *
2705 gen_radiotap_llprefixlen(void)
2709 if (reg_off_ll == -1) {
2711 * We haven't yet assigned a register for the length
2712 * of the radiotap header; allocate one.
2714 reg_off_ll = alloc_reg();
2718 * Load the register containing the radiotap length
2719 * into the X register.
2721 s = new_stmt(BPF_LDX|BPF_MEM);
2722 s->s.k = reg_off_ll;
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.
2734 static struct slist *
2735 gen_ppi_llprefixlen(void)
2739 if (reg_off_ll == -1) {
2741 * We haven't yet assigned a register for the length
2742 * of the radiotap header; allocate one.
2744 reg_off_ll = alloc_reg();
2748 * Load the register containing the PPI length
2749 * into the X register.
2751 s = new_stmt(BPF_LDX|BPF_MEM);
2752 s->s.k = reg_off_ll;
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.
2762 static struct slist *
2763 gen_llprefixlen(void)
2767 case DLT_PRISM_HEADER:
2768 return gen_prism_llprefixlen();
2770 case DLT_IEEE802_11_RADIO_AVS:
2771 return gen_avs_llprefixlen();
2773 case DLT_IEEE802_11_RADIO:
2774 return gen_radiotap_llprefixlen();
2777 return gen_ppi_llprefixlen();
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.
2789 static struct slist *
2794 if (off_macpl_is_variable) {
2795 if (reg_off_macpl == -1) {
2797 * We haven't yet assigned a register for the offset
2798 * of the MAC-layer payload; allocate one.
2800 reg_off_macpl = alloc_reg();
2804 * Load the register containing the offset of the MAC-layer
2805 * payload into the X register.
2807 s = new_stmt(BPF_LDX|BPF_MEM);
2808 s->s.k = reg_off_macpl;
2812 * That offset isn't variable, so we don't need to
2813 * generate any code.
2820 * Map an Ethernet type to the equivalent PPP type.
2823 ethertype_to_ppptype(proto)
2833 case ETHERTYPE_IPV6:
2842 case ETHERTYPE_ATALK:
2856 * I'm assuming the "Bridging PDU"s that go
2857 * over PPP are Spanning Tree Protocol
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.
2874 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
2875 * value, if <= ETHERMTU.
2877 static struct block *
2881 struct block *b0, *b1, *b2;
2883 /* are we checking MPLS-encapsulated packets? */
2884 if (label_stack_depth > 0) {
2888 /* FIXME add other L3 proto IDs */
2889 return gen_mpls_linktype(Q_IP);
2891 case ETHERTYPE_IPV6:
2893 /* FIXME add other L3 proto IDs */
2894 return gen_mpls_linktype(Q_IPV6);
2897 bpf_error("unsupported protocol over mpls");
2903 * Are we testing PPPoE packets?
2907 * The PPPoE session header is part of the
2908 * MAC-layer payload, so all references
2909 * should be relative to the beginning of
2914 * We use Ethernet protocol types inside libpcap;
2915 * map them to the corresponding PPP protocol types.
2917 proto = ethertype_to_ppptype(proto);
2918 return gen_cmp(OR_MACPL, off_linktype, BPF_H, (bpf_int32)proto);
2924 case DLT_NETANALYZER:
2925 case DLT_NETANALYZER_TRANSPARENT:
2926 return gen_ether_linktype(proto);
2934 proto = (proto << 8 | LLCSAP_ISONS);
2938 return gen_cmp(OR_LINK, off_linktype, BPF_H,
2945 case DLT_IEEE802_11:
2946 case DLT_PRISM_HEADER:
2947 case DLT_IEEE802_11_RADIO_AVS:
2948 case DLT_IEEE802_11_RADIO:
2951 * Check that we have a data frame.
2953 b0 = gen_check_802_11_data_frame();
2956 * Now check for the specified link-layer type.
2958 b1 = gen_llc_linktype(proto);
2966 * XXX - check for asynchronous frames, as per RFC 1103.
2968 return gen_llc_linktype(proto);
2974 * XXX - check for LLC PDUs, as per IEEE 802.5.
2976 return gen_llc_linktype(proto);
2980 case DLT_ATM_RFC1483:
2982 case DLT_IP_OVER_FC:
2983 return gen_llc_linktype(proto);
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.
2993 * We assume LANE means Ethernet, not Token Ring.
2997 * Check that the packet doesn't begin with an
2998 * LE Control marker. (We've already generated
3001 b0 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
3006 * Now generate an Ethernet test.
3008 b1 = gen_ether_linktype(proto);
3013 * Check for LLC encapsulation and then check the
3016 b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
3017 b1 = gen_llc_linktype(proto);
3025 return gen_linux_sll_linktype(proto);
3030 case DLT_SLIP_BSDOS:
3033 * These types don't provide any type field; packets
3034 * are always IPv4 or IPv6.
3036 * XXX - for IPv4, check for a version number of 4, and,
3037 * for IPv6, check for a version number of 6?
3042 /* Check for a version number of 4. */
3043 return gen_mcmp(OR_LINK, 0, BPF_B, 0x40, 0xF0);
3045 case ETHERTYPE_IPV6:
3046 /* Check for a version number of 6. */
3047 return gen_mcmp(OR_LINK, 0, BPF_B, 0x60, 0xF0);
3051 return gen_false(); /* always false */
3058 * Raw IPv4, so no type field.
3060 if (proto == ETHERTYPE_IP)
3061 return gen_true(); /* always true */
3063 /* Checking for something other than IPv4; always false */
3070 * Raw IPv6, so no type field.
3073 if (proto == ETHERTYPE_IPV6)
3074 return gen_true(); /* always true */
3077 /* Checking for something other than IPv6; always false */
3084 case DLT_PPP_SERIAL:
3087 * We use Ethernet protocol types inside libpcap;
3088 * map them to the corresponding PPP protocol types.
3090 proto = ethertype_to_ppptype(proto);
3091 return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
3097 * We use Ethernet protocol types inside libpcap;
3098 * map them to the corresponding PPP protocol types.
3104 * Also check for Van Jacobson-compressed IP.
3105 * XXX - do this for other forms of PPP?
3107 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_IP);
3108 b1 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJC);
3110 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJNC);
3115 proto = ethertype_to_ppptype(proto);
3116 return gen_cmp(OR_LINK, off_linktype, BPF_H,
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
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.
3136 * For DLT_LOOP, the link-layer header is a 32-bit
3137 * word containing an AF_ value in *network* byte order.
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.
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.
3154 case ETHERTYPE_IPV6:
3161 * Not a type on which we support filtering.
3162 * XXX - support those that have AF_ values
3163 * #defined on this platform, at least?
3168 if (linktype == DLT_NULL || linktype == DLT_ENC) {
3170 * The AF_ value is in host byte order, but
3171 * the BPF interpreter will convert it to
3172 * network byte order.
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.
3178 * Then we run it through "htonl()", and
3179 * generate code to compare against the result.
3181 if (bpf_pcap->sf.rfile != NULL &&
3182 bpf_pcap->sf.swapped)
3183 proto = SWAPLONG(proto);
3184 proto = htonl(proto);
3186 return (gen_cmp(OR_LINK, 0, BPF_W, (bpf_int32)proto));
3188 #ifdef HAVE_NET_PFVAR_H
3191 * af field is host byte order in contrast to the rest of
3194 if (proto == ETHERTYPE_IP)
3195 return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
3196 BPF_B, (bpf_int32)AF_INET));
3198 else if (proto == ETHERTYPE_IPV6)
3199 return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
3200 BPF_B, (bpf_int32)AF_INET6));
3206 #endif /* HAVE_NET_PFVAR_H */
3209 case DLT_ARCNET_LINUX:
3211 * XXX should we check for first fragment if the protocol
3220 case ETHERTYPE_IPV6:
3221 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
3222 (bpf_int32)ARCTYPE_INET6));
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);
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);
3241 case ETHERTYPE_REVARP:
3242 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
3243 (bpf_int32)ARCTYPE_REVARP));
3245 case ETHERTYPE_ATALK:
3246 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
3247 (bpf_int32)ARCTYPE_ATALK));
3254 case ETHERTYPE_ATALK:
3264 * XXX - assumes a 2-byte Frame Relay header with
3265 * DLCI and flags. What if the address is longer?
3271 * Check for the special NLPID for IP.
3273 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0xcc);
3276 case ETHERTYPE_IPV6:
3278 * Check for the special NLPID for IPv6.
3280 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0x8e);
3285 * Check for several OSI protocols.
3287 * Frame Relay packets typically have an OSI
3288 * NLPID at the beginning; we check for each
3291 * What we check for is the NLPID and a frame
3292 * control field of UI, i.e. 0x03 followed
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);
3309 bpf_error("Multi-link Frame Relay link-layer type filtering not implemented");
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:
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
3339 * FIXME encapsulation specific BPF_ filters
3341 return gen_mcmp(OR_LINK, 0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */
3344 return gen_ipnet_linktype(proto);
3346 case DLT_LINUX_IRDA:
3347 bpf_error("IrDA link-layer type filtering not implemented");
3350 bpf_error("DOCSIS link-layer type filtering not implemented");
3353 case DLT_MTP2_WITH_PHDR:
3354 bpf_error("MTP2 link-layer type filtering not implemented");
3357 bpf_error("ERF link-layer type filtering not implemented");
3361 bpf_error("PFSYNC link-layer type filtering not implemented");
3364 case DLT_LINUX_LAPD:
3365 bpf_error("LAPD link-layer type filtering not implemented");
3369 case DLT_USB_LINUX_MMAPPED:
3370 bpf_error("USB link-layer type filtering not implemented");
3372 case DLT_BLUETOOTH_HCI_H4:
3373 case DLT_BLUETOOTH_HCI_H4_WITH_PHDR:
3374 bpf_error("Bluetooth link-layer type filtering not implemented");
3377 case DLT_CAN_SOCKETCAN:
3378 bpf_error("CAN link-layer type filtering not implemented");
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");
3386 case DLT_IEEE802_16_MAC_CPS_RADIO:
3387 bpf_error("IEEE 802.16 link-layer type filtering not implemented");
3390 bpf_error("SITA link-layer type filtering not implemented");
3393 bpf_error("RAIF1 link-layer type filtering not implemented");
3396 bpf_error("IPMB link-layer type filtering not implemented");
3399 bpf_error("AX.25 link-layer type filtering not implemented");
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).
3410 * Therefore, if "off_linktype" is -1, there's an error.
3412 if (off_linktype == (u_int)-1)
3416 * Any type not handled above should always have an Ethernet
3417 * type at an offset of "off_linktype".
3419 return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
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.
3429 static struct block *
3430 gen_snap(orgcode, ptype)
3431 bpf_u_int32 orgcode;
3434 u_char snapblock[8];
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);
3448 * Generate code to match a particular packet type, for link-layer types
3449 * using 802.2 LLC headers.
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.
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.
3459 static struct block *
3460 gen_llc_linktype(proto)
3464 * XXX - handle token-ring variable-length header.
3470 case LLCSAP_NETBEUI:
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)?
3477 return gen_cmp(OR_MACPL, 0, BPF_H, (bpf_u_int32)
3478 ((proto << 8) | proto));
3482 * XXX - are there ever SNAP frames for IPX on
3483 * non-Ethernet 802.x networks?
3485 return gen_cmp(OR_MACPL, 0, BPF_B,
3486 (bpf_int32)LLCSAP_IPX);
3488 case ETHERTYPE_ATALK:
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).
3495 * XXX - check for an organization code of
3496 * encapsulated Ethernet as well?
3498 return gen_snap(0x080007, ETHERTYPE_ATALK);
3502 * XXX - we don't have to check for IPX 802.3
3503 * here, but should we check for the IPX Ethertype?
3505 if (proto <= ETHERMTU) {
3507 * This is an LLC SAP value, so check
3510 return gen_cmp(OR_MACPL, 0, BPF_B, (bpf_int32)proto);
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).
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
3525 * return gen_snap(0x000000, proto);
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.
3531 return gen_cmp(OR_MACPL, 6, BPF_H, (bpf_int32)proto);
3536 static struct block *
3537 gen_hostop(addr, mask, dir, proto, src_off, dst_off)
3541 u_int src_off, dst_off;
3543 struct block *b0, *b1;
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);
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);
3572 b0 = gen_linktype(proto);
3573 b1 = gen_mcmp(OR_NET, offset, BPF_W, (bpf_int32)addr, mask);
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;
3584 u_int src_off, dst_off;
3586 struct block *b0, *b1;
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);
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);
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]));
3622 b0 = gen_mcmp(OR_NET, offset + 4, BPF_W, ntohl(a[1]), ntohl(m[1]));
3624 b0 = gen_mcmp(OR_NET, offset + 0, BPF_W, ntohl(a[0]), ntohl(m[0]));
3626 b0 = gen_linktype(proto);
3632 static struct block *
3633 gen_ehostop(eaddr, dir)
3634 register const u_char *eaddr;
3637 register struct block *b0, *b1;
3641 return gen_bcmp(OR_LINK, off_mac + 6, 6, eaddr);
3644 return gen_bcmp(OR_LINK, off_mac + 0, 6, eaddr);
3647 b0 = gen_ehostop(eaddr, Q_SRC);
3648 b1 = gen_ehostop(eaddr, Q_DST);
3654 b0 = gen_ehostop(eaddr, Q_SRC);
3655 b1 = gen_ehostop(eaddr, Q_DST);
3660 bpf_error("'addr1' is only supported on 802.11 with 802.11 headers");
3664 bpf_error("'addr2' is only supported on 802.11 with 802.11 headers");
3668 bpf_error("'addr3' is only supported on 802.11 with 802.11 headers");
3672 bpf_error("'addr4' is only supported on 802.11 with 802.11 headers");
3676 bpf_error("'ra' is only supported on 802.11 with 802.11 headers");
3680 bpf_error("'ta' is only supported on 802.11 with 802.11 headers");
3688 * Like gen_ehostop, but for DLT_FDDI
3690 static struct block *
3691 gen_fhostop(eaddr, dir)
3692 register const u_char *eaddr;
3695 struct block *b0, *b1;
3700 return gen_bcmp(OR_LINK, 6 + 1 + pcap_fddipad, 6, eaddr);
3702 return gen_bcmp(OR_LINK, 6 + 1, 6, eaddr);
3707 return gen_bcmp(OR_LINK, 0 + 1 + pcap_fddipad, 6, eaddr);
3709 return gen_bcmp(OR_LINK, 0 + 1, 6, eaddr);
3713 b0 = gen_fhostop(eaddr, Q_SRC);
3714 b1 = gen_fhostop(eaddr, Q_DST);
3720 b0 = gen_fhostop(eaddr, Q_SRC);
3721 b1 = gen_fhostop(eaddr, Q_DST);
3726 bpf_error("'addr1' is only supported on 802.11");
3730 bpf_error("'addr2' is only supported on 802.11");
3734 bpf_error("'addr3' is only supported on 802.11");
3738 bpf_error("'addr4' is only supported on 802.11");
3742 bpf_error("'ra' is only supported on 802.11");
3746 bpf_error("'ta' is only supported on 802.11");
3754 * Like gen_ehostop, but for DLT_IEEE802 (Token Ring)
3756 static struct block *
3757 gen_thostop(eaddr, dir)
3758 register const u_char *eaddr;
3761 register struct block *b0, *b1;
3765 return gen_bcmp(OR_LINK, 8, 6, eaddr);
3768 return gen_bcmp(OR_LINK, 2, 6, eaddr);
3771 b0 = gen_thostop(eaddr, Q_SRC);
3772 b1 = gen_thostop(eaddr, Q_DST);
3778 b0 = gen_thostop(eaddr, Q_SRC);
3779 b1 = gen_thostop(eaddr, Q_DST);
3784 bpf_error("'addr1' is only supported on 802.11");
3788 bpf_error("'addr2' is only supported on 802.11");
3792 bpf_error("'addr3' is only supported on 802.11");
3796 bpf_error("'addr4' is only supported on 802.11");
3800 bpf_error("'ra' is only supported on 802.11");
3804 bpf_error("'ta' is only supported on 802.11");
3812 * Like gen_ehostop, but for DLT_IEEE802_11 (802.11 wireless LAN) and
3813 * various 802.11 + radio headers.
3815 static struct block *
3816 gen_wlanhostop(eaddr, dir)
3817 register const u_char *eaddr;
3820 register struct block *b0, *b1, *b2;
3821 register struct slist *s;
3823 #ifdef ENABLE_WLAN_FILTERING_PATCH
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
3831 #endif /* ENABLE_WLAN_FILTERING_PATCH */
3838 * For control frames, there is no SA.
3840 * For management frames, SA is at an
3841 * offset of 10 from the beginning of
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
3855 * Generate the tests to be done for data frames
3858 * First, check for To DS set, i.e. check "link[1] & 0x01".
3860 s = gen_load_a(OR_LINK, 1, BPF_B);
3861 b1 = new_block(JMP(BPF_JSET));
3862 b1->s.k = 0x01; /* To DS */
3866 * If To DS is set, the SA is at 24.
3868 b0 = gen_bcmp(OR_LINK, 24, 6, eaddr);
3872 * Now, check for To DS not set, i.e. check
3873 * "!(link[1] & 0x01)".
3875 s = gen_load_a(OR_LINK, 1, BPF_B);
3876 b2 = new_block(JMP(BPF_JSET));
3877 b2->s.k = 0x01; /* To DS */
3882 * If To DS is not set, the SA is at 16.
3884 b1 = gen_bcmp(OR_LINK, 16, 6, eaddr);
3888 * Now OR together the last two checks. That gives
3889 * the complete set of checks for data frames with
3895 * Now check for From DS being set, and AND that with
3896 * the ORed-together checks.
3898 s = gen_load_a(OR_LINK, 1, BPF_B);
3899 b1 = new_block(JMP(BPF_JSET));
3900 b1->s.k = 0x02; /* From DS */
3905 * Now check for data frames with From DS not set.
3907 s = gen_load_a(OR_LINK, 1, BPF_B);
3908 b2 = new_block(JMP(BPF_JSET));
3909 b2->s.k = 0x02; /* From DS */
3914 * If From DS isn't set, the SA is at 10.
3916 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
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.
3927 * Now check for a data frame.
3928 * I.e, check "link[0] & 0x08".
3930 s = gen_load_a(OR_LINK, 0, BPF_B);
3931 b1 = new_block(JMP(BPF_JSET));
3936 * AND that with the checks done for data frames.
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)".
3945 s = gen_load_a(OR_LINK, 0, BPF_B);
3946 b2 = new_block(JMP(BPF_JSET));
3952 * For management frames, the SA is at 10.
3954 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
3958 * OR that with the checks done for data frames.
3959 * That gives the checks done for management and
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
3970 * I.e., check "!(link[0] & 0x04)".
3972 s = gen_load_a(OR_LINK, 0, BPF_B);
3973 b1 = new_block(JMP(BPF_JSET));
3979 * AND that with the checks for data and management
3989 * For control frames, there is no DA.
3991 * For management frames, DA is at an
3992 * offset of 4 from the beginning of
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
4003 * Generate the tests to be done for data frames.
4005 * First, check for To DS set, i.e. "link[1] & 0x01".
4007 s = gen_load_a(OR_LINK, 1, BPF_B);
4008 b1 = new_block(JMP(BPF_JSET));
4009 b1->s.k = 0x01; /* To DS */
4013 * If To DS is set, the DA is at 16.
4015 b0 = gen_bcmp(OR_LINK, 16, 6, eaddr);
4019 * Now, check for To DS not set, i.e. check
4020 * "!(link[1] & 0x01)".
4022 s = gen_load_a(OR_LINK, 1, BPF_B);
4023 b2 = new_block(JMP(BPF_JSET));
4024 b2->s.k = 0x01; /* To DS */
4029 * If To DS is not set, the DA is at 4.
4031 b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
4035 * Now OR together the last two checks. That gives
4036 * the complete set of checks for data frames.
4041 * Now check for a data frame.
4042 * I.e, check "link[0] & 0x08".
4044 s = gen_load_a(OR_LINK, 0, BPF_B);
4045 b1 = new_block(JMP(BPF_JSET));
4050 * AND that with the checks done for data frames.
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)".
4059 s = gen_load_a(OR_LINK, 0, BPF_B);
4060 b2 = new_block(JMP(BPF_JSET));
4066 * For management frames, the DA is at 4.
4068 b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
4072 * OR that with the checks done for data frames.
4073 * That gives the checks done for management and
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
4084 * I.e., check "!(link[0] & 0x04)".
4086 s = gen_load_a(OR_LINK, 0, BPF_B);
4087 b1 = new_block(JMP(BPF_JSET));
4093 * AND that with the checks for data and management
4101 * Not present in management frames; addr1 in other
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)".
4110 s = gen_load_a(OR_LINK, 0, BPF_B);
4111 b1 = new_block(JMP(BPF_JSET));
4118 b0 = gen_bcmp(OR_LINK, 4, 6, eaddr);
4121 * AND that with the check of addr1.
4128 * Not present in management frames; addr2, if present,
4133 * Not present in CTS or ACK control frames.
4135 b0 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
4136 IEEE80211_FC0_TYPE_MASK);
4138 b1 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS,
4139 IEEE80211_FC0_SUBTYPE_MASK);
4141 b2 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK,
4142 IEEE80211_FC0_SUBTYPE_MASK);
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)".
4152 s = gen_load_a(OR_LINK, 0, BPF_B);
4153 b1 = new_block(JMP(BPF_JSET));
4158 * AND that with the check for frames other than
4159 * CTS and ACK frames.
4166 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
4171 * XXX - add BSSID keyword?
4174 return (gen_bcmp(OR_LINK, 4, 6, eaddr));
4178 * Not present in CTS or ACK control frames.
4180 b0 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
4181 IEEE80211_FC0_TYPE_MASK);
4183 b1 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_CTS,
4184 IEEE80211_FC0_SUBTYPE_MASK);
4186 b2 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_SUBTYPE_ACK,
4187 IEEE80211_FC0_SUBTYPE_MASK);
4191 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
4197 * Not present in control frames.
4199 b0 = gen_mcmp(OR_LINK, 0, BPF_B, IEEE80211_FC0_TYPE_CTL,
4200 IEEE80211_FC0_TYPE_MASK);
4202 b1 = gen_bcmp(OR_LINK, 16, 6, eaddr);
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.
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);
4220 b0 = gen_wlanhostop(eaddr, Q_SRC);
4221 b1 = gen_wlanhostop(eaddr, Q_DST);
4227 b0 = gen_wlanhostop(eaddr, Q_SRC);
4228 b1 = gen_wlanhostop(eaddr, Q_DST);
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.)
4241 static struct block *
4242 gen_ipfchostop(eaddr, dir)
4243 register const u_char *eaddr;
4246 register struct block *b0, *b1;
4250 return gen_bcmp(OR_LINK, 10, 6, eaddr);
4253 return gen_bcmp(OR_LINK, 2, 6, eaddr);
4256 b0 = gen_ipfchostop(eaddr, Q_SRC);
4257 b1 = gen_ipfchostop(eaddr, Q_DST);
4263 b0 = gen_ipfchostop(eaddr, Q_SRC);
4264 b1 = gen_ipfchostop(eaddr, Q_DST);
4269 bpf_error("'addr1' is only supported on 802.11");
4273 bpf_error("'addr2' is only supported on 802.11");
4277 bpf_error("'addr3' is only supported on 802.11");
4281 bpf_error("'addr4' is only supported on 802.11");
4285 bpf_error("'ra' is only supported on 802.11");
4289 bpf_error("'ta' is only supported on 802.11");
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.
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.
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.
4314 static struct block *
4315 gen_dnhostop(addr, dir)
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 */
4326 offset_sh = 1; /* follows flags */
4327 offset_lh = 7; /* flgs,darea,dsubarea,HIORD */
4331 offset_sh = 3; /* follows flags, dstnode */
4332 offset_lh = 15; /* flgs,darea,dsubarea,did,sarea,ssub,HIORD */
4336 /* Inefficient because we do our Calvinball dance twice */
4337 b0 = gen_dnhostop(addr, Q_SRC);
4338 b1 = gen_dnhostop(addr, Q_DST);
4344 /* Inefficient because we do our Calvinball dance twice */
4345 b0 = gen_dnhostop(addr, Q_SRC);
4346 b1 = gen_dnhostop(addr, Q_DST);
4351 bpf_error("ISO host filtering not implemented");
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));
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));
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));
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));
4380 /* Combine with test for linktype */
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.
4390 static struct block *
4391 gen_mpls_linktype(proto)
4394 struct block *b0, *b1;
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);
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);
4419 static struct block *
4420 gen_host(addr, mask, proto, dir, type)
4427 struct block *b0, *b1;
4428 const char *typestr;
4438 b0 = gen_host(addr, mask, Q_IP, dir, type);
4440 * Only check for non-IPv4 addresses if we're not
4441 * checking MPLS-encapsulated packets.
4443 if (label_stack_depth == 0) {
4444 b1 = gen_host(addr, mask, Q_ARP, dir, type);
4446 b0 = gen_host(addr, mask, Q_RARP, dir, type);
4452 return gen_hostop(addr, mask, dir, ETHERTYPE_IP, 12, 16);
4455 return gen_hostop(addr, mask, dir, ETHERTYPE_REVARP, 14, 24);
4458 return gen_hostop(addr, mask, dir, ETHERTYPE_ARP, 14, 24);
4461 bpf_error("'tcp' modifier applied to %s", typestr);
4464 bpf_error("'sctp' modifier applied to %s", typestr);
4467 bpf_error("'udp' modifier applied to %s", typestr);
4470 bpf_error("'icmp' modifier applied to %s", typestr);
4473 bpf_error("'igmp' modifier applied to %s", typestr);
4476 bpf_error("'igrp' modifier applied to %s", typestr);
4479 bpf_error("'pim' modifier applied to %s", typestr);
4482 bpf_error("'vrrp' modifier applied to %s", typestr);
4485 bpf_error("'carp' modifier applied to %s", typestr);
4488 bpf_error("ATALK host filtering not implemented");
4491 bpf_error("AARP host filtering not implemented");
4494 return gen_dnhostop(addr, dir);
4497 bpf_error("SCA host filtering not implemented");
4500 bpf_error("LAT host filtering not implemented");
4503 bpf_error("MOPDL host filtering not implemented");
4506 bpf_error("MOPRC host filtering not implemented");
4510 bpf_error("'ip6' modifier applied to ip host");
4513 bpf_error("'icmp6' modifier applied to %s", typestr);
4517 bpf_error("'ah' modifier applied to %s", typestr);
4520 bpf_error("'esp' modifier applied to %s", typestr);
4523 bpf_error("ISO host filtering not implemented");
4526 bpf_error("'esis' modifier applied to %s", typestr);
4529 bpf_error("'isis' modifier applied to %s", typestr);
4532 bpf_error("'clnp' modifier applied to %s", typestr);
4535 bpf_error("'stp' modifier applied to %s", typestr);
4538 bpf_error("IPX host filtering not implemented");
4541 bpf_error("'netbeui' modifier applied to %s", typestr);
4544 bpf_error("'radio' modifier applied to %s", typestr);
4553 static struct block *
4554 gen_host6(addr, mask, proto, dir, type)
4555 struct in6_addr *addr;
4556 struct in6_addr *mask;
4561 const char *typestr;
4571 return gen_host6(addr, mask, Q_IPV6, dir, type);
4574 bpf_error("'ip' modifier applied to ip6 %s", typestr);
4577 bpf_error("'rarp' modifier applied to ip6 %s", typestr);
4580 bpf_error("'arp' modifier applied to ip6 %s", typestr);
4583 bpf_error("'sctp' modifier applied to %s", typestr);
4586 bpf_error("'tcp' modifier applied to %s", typestr);
4589 bpf_error("'udp' modifier applied to %s", typestr);
4592 bpf_error("'icmp' modifier applied to %s", typestr);
4595 bpf_error("'igmp' modifier applied to %s", typestr);
4598 bpf_error("'igrp' modifier applied to %s", typestr);
4601 bpf_error("'pim' modifier applied to %s", typestr);
4604 bpf_error("'vrrp' modifier applied to %s", typestr);
4607 bpf_error("'carp' modifier applied to %s", typestr);
4610 bpf_error("ATALK host filtering not implemented");
4613 bpf_error("AARP host filtering not implemented");
4616 bpf_error("'decnet' modifier applied to ip6 %s", typestr);
4619 bpf_error("SCA host filtering not implemented");
4622 bpf_error("LAT host filtering not implemented");
4625 bpf_error("MOPDL host filtering not implemented");
4628 bpf_error("MOPRC host filtering not implemented");
4631 return gen_hostop6(addr, mask, dir, ETHERTYPE_IPV6, 8, 24);
4634 bpf_error("'icmp6' modifier applied to %s", typestr);
4637 bpf_error("'ah' modifier applied to %s", typestr);
4640 bpf_error("'esp' modifier applied to %s", typestr);
4643 bpf_error("ISO host filtering not implemented");
4646 bpf_error("'esis' modifier applied to %s", typestr);
4649 bpf_error("'isis' modifier applied to %s", typestr);
4652 bpf_error("'clnp' modifier applied to %s", typestr);
4655 bpf_error("'stp' modifier applied to %s", typestr);
4658 bpf_error("IPX host filtering not implemented");
4661 bpf_error("'netbeui' modifier applied to %s", typestr);
4664 bpf_error("'radio' modifier applied to %s", typestr);
4674 static struct block *
4675 gen_gateway(eaddr, alist, proto, dir)
4676 const u_char *eaddr;
4677 bpf_u_int32 **alist;
4681 struct block *b0, *b1, *tmp;
4684 bpf_error("direction applied to 'gateway'");
4693 case DLT_NETANALYZER:
4694 case DLT_NETANALYZER_TRANSPARENT:
4695 b0 = gen_ehostop(eaddr, Q_OR);
4698 b0 = gen_fhostop(eaddr, Q_OR);
4701 b0 = gen_thostop(eaddr, Q_OR);
4703 case DLT_IEEE802_11:
4704 case DLT_PRISM_HEADER:
4705 case DLT_IEEE802_11_RADIO_AVS:
4706 case DLT_IEEE802_11_RADIO:
4708 b0 = gen_wlanhostop(eaddr, Q_OR);
4713 "'gateway' supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
4715 * Check that the packet doesn't begin with an
4716 * LE Control marker. (We've already generated
4719 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS,
4724 * Now check the MAC address.
4726 b0 = gen_ehostop(eaddr, Q_OR);
4729 case DLT_IP_OVER_FC:
4730 b0 = gen_ipfchostop(eaddr, Q_OR);
4734 "'gateway' supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
4736 b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR, Q_HOST);
4738 tmp = gen_host(**alist++, 0xffffffff, proto, Q_OR,
4747 bpf_error("illegal modifier of 'gateway'");
4753 gen_proto_abbrev(proto)
4762 b1 = gen_proto(IPPROTO_SCTP, Q_IP, Q_DEFAULT);
4764 b0 = gen_proto(IPPROTO_SCTP, Q_IPV6, Q_DEFAULT);
4770 b1 = gen_proto(IPPROTO_TCP, Q_IP, Q_DEFAULT);
4772 b0 = gen_proto(IPPROTO_TCP, Q_IPV6, Q_DEFAULT);
4778 b1 = gen_proto(IPPROTO_UDP, Q_IP, Q_DEFAULT);
4780 b0 = gen_proto(IPPROTO_UDP, Q_IPV6, Q_DEFAULT);
4786 b1 = gen_proto(IPPROTO_ICMP, Q_IP, Q_DEFAULT);
4789 #ifndef IPPROTO_IGMP
4790 #define IPPROTO_IGMP 2
4794 b1 = gen_proto(IPPROTO_IGMP, Q_IP, Q_DEFAULT);
4797 #ifndef IPPROTO_IGRP
4798 #define IPPROTO_IGRP 9
4801 b1 = gen_proto(IPPROTO_IGRP, Q_IP, Q_DEFAULT);
4805 #define IPPROTO_PIM 103
4809 b1 = gen_proto(IPPROTO_PIM, Q_IP, Q_DEFAULT);
4811 b0 = gen_proto(IPPROTO_PIM, Q_IPV6, Q_DEFAULT);
4816 #ifndef IPPROTO_VRRP
4817 #define IPPROTO_VRRP 112
4821 b1 = gen_proto(IPPROTO_VRRP, Q_IP, Q_DEFAULT);
4824 #ifndef IPPROTO_CARP
4825 #define IPPROTO_CARP 112
4829 b1 = gen_proto(IPPROTO_CARP, Q_IP, Q_DEFAULT);
4833 b1 = gen_linktype(ETHERTYPE_IP);
4837 b1 = gen_linktype(ETHERTYPE_ARP);
4841 b1 = gen_linktype(ETHERTYPE_REVARP);
4845 bpf_error("link layer applied in wrong context");
4848 b1 = gen_linktype(ETHERTYPE_ATALK);
4852 b1 = gen_linktype(ETHERTYPE_AARP);
4856 b1 = gen_linktype(ETHERTYPE_DN);
4860 b1 = gen_linktype(ETHERTYPE_SCA);
4864 b1 = gen_linktype(ETHERTYPE_LAT);
4868 b1 = gen_linktype(ETHERTYPE_MOPDL);
4872 b1 = gen_linktype(ETHERTYPE_MOPRC);
4877 b1 = gen_linktype(ETHERTYPE_IPV6);
4880 #ifndef IPPROTO_ICMPV6
4881 #define IPPROTO_ICMPV6 58
4884 b1 = gen_proto(IPPROTO_ICMPV6, Q_IPV6, Q_DEFAULT);
4889 #define IPPROTO_AH 51
4892 b1 = gen_proto(IPPROTO_AH, Q_IP, Q_DEFAULT);
4894 b0 = gen_proto(IPPROTO_AH, Q_IPV6, Q_DEFAULT);
4900 #define IPPROTO_ESP 50
4903 b1 = gen_proto(IPPROTO_ESP, Q_IP, Q_DEFAULT);
4905 b0 = gen_proto(IPPROTO_ESP, Q_IPV6, Q_DEFAULT);
4911 b1 = gen_linktype(LLCSAP_ISONS);
4915 b1 = gen_proto(ISO9542_ESIS, Q_ISO, Q_DEFAULT);
4919 b1 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
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 */
4926 b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
4928 b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
4930 b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
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 */
4938 b0 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
4940 b0 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
4942 b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
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);
4950 b0 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT);
4955 b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
4956 b1 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
4961 b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
4962 b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
4964 b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
4966 b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
4971 b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
4972 b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
4977 b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
4978 b1 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
4983 b1 = gen_proto(ISO8473_CLNP, Q_ISO, Q_DEFAULT);
4987 b1 = gen_linktype(LLCSAP_8021D);
4991 b1 = gen_linktype(LLCSAP_IPX);
4995 b1 = gen_linktype(LLCSAP_NETBEUI);
4999 bpf_error("'radio' is not a valid protocol type");
5007 static struct block *
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));
5024 * Generate a comparison to a port value in the transport-layer header
5025 * at the specified offset from the beginning of that header.
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
5032 static struct block *
5033 gen_portatom(off, v)
5037 return gen_cmp(OR_TRAN_IPV4, off, BPF_H, v);
5041 static struct block *
5042 gen_portatom6(off, v)
5046 return gen_cmp(OR_TRAN_IPV6, off, BPF_H, v);
5051 gen_portop(port, proto, dir)
5052 int port, proto, dir;
5054 struct block *b0, *b1, *tmp;
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);
5063 b1 = gen_portatom(0, (bpf_int32)port);
5067 b1 = gen_portatom(2, (bpf_int32)port);
5072 tmp = gen_portatom(0, (bpf_int32)port);
5073 b1 = gen_portatom(2, (bpf_int32)port);
5078 tmp = gen_portatom(0, (bpf_int32)port);
5079 b1 = gen_portatom(2, (bpf_int32)port);
5091 static struct block *
5092 gen_port(port, ip_proto, dir)
5097 struct block *b0, *b1, *tmp;
5102 * For FDDI, RFC 1188 says that SNAP encapsulation is used,
5103 * not LLC encapsulation with LLCSAP_IP.
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
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.
5114 * So we always check for ETHERTYPE_IP.
5116 b0 = gen_linktype(ETHERTYPE_IP);
5122 b1 = gen_portop(port, ip_proto, dir);
5126 tmp = gen_portop(port, IPPROTO_TCP, dir);
5127 b1 = gen_portop(port, IPPROTO_UDP, dir);
5129 tmp = gen_portop(port, IPPROTO_SCTP, dir);
5142 gen_portop6(port, proto, dir)
5143 int port, proto, dir;
5145 struct block *b0, *b1, *tmp;
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);
5153 b1 = gen_portatom6(0, (bpf_int32)port);
5157 b1 = gen_portatom6(2, (bpf_int32)port);
5162 tmp = gen_portatom6(0, (bpf_int32)port);
5163 b1 = gen_portatom6(2, (bpf_int32)port);
5168 tmp = gen_portatom6(0, (bpf_int32)port);
5169 b1 = gen_portatom6(2, (bpf_int32)port);
5181 static struct block *
5182 gen_port6(port, ip_proto, dir)
5187 struct block *b0, *b1, *tmp;
5189 /* link proto ip6 */
5190 b0 = gen_linktype(ETHERTYPE_IPV6);
5196 b1 = gen_portop6(port, ip_proto, dir);
5200 tmp = gen_portop6(port, IPPROTO_TCP, dir);
5201 b1 = gen_portop6(port, IPPROTO_UDP, dir);
5203 tmp = gen_portop6(port, IPPROTO_SCTP, dir);
5215 /* gen_portrange code */
5216 static struct block *
5217 gen_portrangeatom(off, v1, v2)
5221 struct block *b1, *b2;
5225 * Reverse the order of the ports, so v1 is the lower one.
5234 b1 = gen_cmp_ge(OR_TRAN_IPV4, off, BPF_H, v1);
5235 b2 = gen_cmp_le(OR_TRAN_IPV4, off, BPF_H, v2);
5243 gen_portrangeop(port1, port2, proto, dir)
5248 struct block *b0, *b1, *tmp;
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);
5257 b1 = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
5261 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
5266 tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
5267 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
5272 tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
5273 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
5285 static struct block *
5286 gen_portrange(port1, port2, ip_proto, dir)
5291 struct block *b0, *b1, *tmp;
5294 b0 = gen_linktype(ETHERTYPE_IP);
5300 b1 = gen_portrangeop(port1, port2, ip_proto, dir);
5304 tmp = gen_portrangeop(port1, port2, IPPROTO_TCP, dir);
5305 b1 = gen_portrangeop(port1, port2, IPPROTO_UDP, dir);
5307 tmp = gen_portrangeop(port1, port2, IPPROTO_SCTP, dir);
5319 static struct block *
5320 gen_portrangeatom6(off, v1, v2)
5324 struct block *b1, *b2;
5328 * Reverse the order of the ports, so v1 is the lower one.
5337 b1 = gen_cmp_ge(OR_TRAN_IPV6, off, BPF_H, v1);
5338 b2 = gen_cmp_le(OR_TRAN_IPV6, off, BPF_H, v2);
5346 gen_portrangeop6(port1, port2, proto, dir)
5351 struct block *b0, *b1, *tmp;
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);
5359 b1 = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
5363 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
5368 tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
5369 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
5374 tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
5375 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
5387 static struct block *
5388 gen_portrange6(port1, port2, ip_proto, dir)
5393 struct block *b0, *b1, *tmp;
5395 /* link proto ip6 */
5396 b0 = gen_linktype(ETHERTYPE_IPV6);
5402 b1 = gen_portrangeop6(port1, port2, ip_proto, dir);
5406 tmp = gen_portrangeop6(port1, port2, IPPROTO_TCP, dir);
5407 b1 = gen_portrangeop6(port1, port2, IPPROTO_UDP, dir);
5409 tmp = gen_portrangeop6(port1, port2, IPPROTO_SCTP, dir);
5422 lookup_proto(name, proto)
5423 register const char *name;
5433 v = pcap_nametoproto(name);
5434 if (v == PROTO_UNDEF)
5435 bpf_error("unknown ip proto '%s'", name);
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);
5449 if (strcmp(name, "esis") == 0)
5451 else if (strcmp(name, "isis") == 0)
5453 else if (strcmp(name, "clnp") == 0)
5456 bpf_error("unknown osi proto '%s'", name);
5476 static struct block *
5477 gen_protochain(v, proto, dir)
5482 #ifdef NO_PROTOCHAIN
5483 return gen_proto(v, proto, dir);
5485 struct block *b0, *b;
5486 struct slist *s[100];
5487 int fix2, fix3, fix4, fix5;
5488 int ahcheck, again, end;
5490 int reg2 = alloc_reg();
5492 memset(s, 0, sizeof(s));
5493 fix2 = fix3 = fix4 = fix5 = 0;
5500 b0 = gen_protochain(v, Q_IP, dir);
5501 b = gen_protochain(v, Q_IPV6, dir);
5505 bpf_error("bad protocol applied for 'protochain'");
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.)
5522 case DLT_IEEE802_11:
5523 case DLT_PRISM_HEADER:
5524 case DLT_IEEE802_11_RADIO_AVS:
5525 case DLT_IEEE802_11_RADIO:
5527 bpf_error("'protochain' not supported with 802.11");
5530 no_optimize = 1; /*this code is not compatible with optimzer yet */
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.
5538 s[i] = new_stmt(0); /*dummy*/
5543 b0 = gen_linktype(ETHERTYPE_IP);
5546 s[i] = new_stmt(BPF_LD|BPF_ABS|BPF_B);
5547 s[i]->s.k = off_macpl + off_nl + 9;
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;
5556 b0 = gen_linktype(ETHERTYPE_IPV6);
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;
5562 /* X = sizeof(struct ip6_hdr) */
5563 s[i] = new_stmt(BPF_LDX|BPF_IMM);
5569 bpf_error("unsupported proto to gen_protochain");
5573 /* again: if (A == v) goto end; else fall through; */
5575 s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
5577 s[i]->s.jt = NULL; /*later*/
5578 s[i]->s.jf = NULL; /*update in next stmt*/
5582 #ifndef IPPROTO_NONE
5583 #define IPPROTO_NONE 59
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];
5595 if (proto == Q_IPV6) {
5596 int v6start, v6end, v6advance, j;
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];
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;
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;
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;
5632 * A = P[X + packet head];
5633 * X = X + (P[X + packet head + 1] + 1) * 8;
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;
5640 s[i] = new_stmt(BPF_ST);
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;
5648 s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
5652 s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K);
5656 s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_X);
5660 s[i] = new_stmt(BPF_MISC|BPF_TAX);
5663 s[i] = new_stmt(BPF_LD|BPF_MEM);
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];
5674 for (j = v6start; j <= v6end; j++)
5675 s[j]->s.jt = s[v6advance];
5680 s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
5682 s[fix2]->s.jf = s[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;
5694 s[fix3]->s.jf = s[ahcheck];
5701 * X = X + (P[X + 1] + 2) * 4;
5704 s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA);
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;
5711 s[i] = new_stmt(BPF_ST);
5715 s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA);
5718 s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
5722 s[i] = new_stmt(BPF_MISC|BPF_TAX);
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;
5729 s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
5733 s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K);
5737 s[i] = new_stmt(BPF_MISC|BPF_TAX);
5740 s[i] = new_stmt(BPF_LD|BPF_MEM);
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;
5751 s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
5753 s[fix2]->s.jt = s[end];
5754 s[fix4]->s.jf = s[end];
5755 s[fix5]->s.jt = s[end];
5762 for (i = 0; i < max - 1; i++)
5763 s[i]->next = s[i + 1];
5764 s[max - 1]->next = NULL;
5769 b = new_block(JMP(BPF_JEQ));
5770 b->stmts = s[1]; /*remember, s[0] is dummy*/
5780 static struct block *
5781 gen_check_802_11_data_frame()
5784 struct block *b0, *b1;
5787 * A data frame has the 0x08 bit (b3) in the frame control field set
5788 * and the 0x04 bit (b2) clear.
5790 s = gen_load_a(OR_LINK, 0, BPF_B);
5791 b0 = new_block(JMP(BPF_JSET));
5795 s = gen_load_a(OR_LINK, 0, BPF_B);
5796 b1 = new_block(JMP(BPF_JSET));
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>.
5812 * If <proto> is Q_DEFAULT, i.e. just "proto" was specified, it checks
5813 * against Q_IP and Q_IPV6.
5815 static struct block *
5816 gen_proto(v, proto, dir)
5821 struct block *b0, *b1;
5823 if (dir != Q_DEFAULT)
5824 bpf_error("direction applied to 'proto'");
5829 b0 = gen_proto(v, Q_IP, dir);
5830 b1 = gen_proto(v, Q_IPV6, dir);
5838 * For FDDI, RFC 1188 says that SNAP encapsulation is used,
5839 * not LLC encapsulation with LLCSAP_IP.
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
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.
5850 * So we always check for ETHERTYPE_IP.
5852 b0 = gen_linktype(ETHERTYPE_IP);
5854 b1 = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)v);
5856 b1 = gen_protochain(v, Q_IP);
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
5874 * What we check for is the NLPID and a frame
5875 * control field value of UI, i.e. 0x03 followed
5878 * XXX - assumes a 2-byte Frame Relay header with
5879 * DLCI and flags. What if the address is longer?
5881 * XXX - what about SNAP-encapsulated frames?
5883 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | v);
5889 * Cisco uses an Ethertype lookalike - for OSI,
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);
5899 b0 = gen_linktype(LLCSAP_ISONS);
5900 b1 = gen_cmp(OR_NET_NOSNAP, 0, BPF_B, (long)v);
5906 b0 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
5908 * 4 is the offset of the PDU type relative to the IS-IS
5911 b1 = gen_cmp(OR_NET_NOSNAP, 4, BPF_B, (long)v);
5916 bpf_error("arp does not encapsulate another protocol");
5920 bpf_error("rarp does not encapsulate another protocol");
5924 bpf_error("atalk encapsulation is not specifiable");
5928 bpf_error("decnet encapsulation is not specifiable");
5932 bpf_error("sca does not encapsulate another protocol");
5936 bpf_error("lat does not encapsulate another protocol");
5940 bpf_error("moprc does not encapsulate another protocol");
5944 bpf_error("mopdl does not encapsulate another protocol");
5948 return gen_linktype(v);
5951 bpf_error("'udp proto' is bogus");
5955 bpf_error("'tcp proto' is bogus");
5959 bpf_error("'sctp proto' is bogus");
5963 bpf_error("'icmp proto' is bogus");
5967 bpf_error("'igmp proto' is bogus");
5971 bpf_error("'igrp proto' is bogus");
5975 bpf_error("'pim proto' is bogus");
5979 bpf_error("'vrrp proto' is bogus");
5983 bpf_error("'carp proto' is bogus");
5988 b0 = gen_linktype(ETHERTYPE_IPV6);
5990 b1 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)v);
5992 b1 = gen_protochain(v, Q_IPV6);
5998 bpf_error("'icmp6 proto' is bogus");
6002 bpf_error("'ah proto' is bogus");
6005 bpf_error("'ah proto' is bogus");
6008 bpf_error("'stp proto' is bogus");
6011 bpf_error("'ipx proto' is bogus");
6014 bpf_error("'netbeui proto' is bogus");
6017 bpf_error("'radio proto' is bogus");
6028 register const char *name;
6031 int proto = q.proto;
6035 bpf_u_int32 mask, addr;
6037 bpf_u_int32 **alist;
6040 struct sockaddr_in *sin4;
6041 struct sockaddr_in6 *sin6;
6042 struct addrinfo *res, *res0;
6043 struct in6_addr mask128;
6045 struct block *b, *tmp;
6046 int port, real_proto;
6052 addr = pcap_nametonetaddr(name);
6054 bpf_error("unknown network '%s'", name);
6055 /* Left justify network addr and calculate its network mask */
6057 while (addr && (addr & 0xff000000) == 0) {
6061 return gen_host(addr, mask, proto, dir, q.addr);
6065 if (proto == Q_LINK) {
6069 case DLT_NETANALYZER:
6070 case DLT_NETANALYZER_TRANSPARENT:
6071 eaddr = pcap_ether_hostton(name);
6074 "unknown ether host '%s'", name);
6075 b = gen_ehostop(eaddr, dir);
6080 eaddr = pcap_ether_hostton(name);
6083 "unknown FDDI host '%s'", name);
6084 b = gen_fhostop(eaddr, dir);
6089 eaddr = pcap_ether_hostton(name);
6092 "unknown token ring host '%s'", name);
6093 b = gen_thostop(eaddr, dir);
6097 case DLT_IEEE802_11:
6098 case DLT_PRISM_HEADER:
6099 case DLT_IEEE802_11_RADIO_AVS:
6100 case DLT_IEEE802_11_RADIO:
6102 eaddr = pcap_ether_hostton(name);
6105 "unknown 802.11 host '%s'", name);
6106 b = gen_wlanhostop(eaddr, dir);
6110 case DLT_IP_OVER_FC:
6111 eaddr = pcap_ether_hostton(name);
6114 "unknown Fibre Channel host '%s'", name);
6115 b = gen_ipfchostop(eaddr, dir);
6124 * Check that the packet doesn't begin
6125 * with an LE Control marker. (We've
6126 * already generated a test for LANE.)
6128 tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS,
6132 eaddr = pcap_ether_hostton(name);
6135 "unknown ether host '%s'", name);
6136 b = gen_ehostop(eaddr, dir);
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);
6146 * I don't think DECNET hosts can be multihomed, so
6147 * there is no need to build up a list of addresses
6149 return (gen_host(dn_addr, 0, proto, dir, q.addr));
6152 alist = pcap_nametoaddr(name);
6153 if (alist == NULL || *alist == NULL)
6154 bpf_error("unknown host '%s'", name);
6156 if (off_linktype == (u_int)-1 && tproto == Q_DEFAULT)
6158 b = gen_host(**alist++, 0xffffffff, tproto, dir, q.addr);
6160 tmp = gen_host(**alist++, 0xffffffff,
6161 tproto, dir, q.addr);
6167 memset(&mask128, 0xff, sizeof(mask128));
6168 res0 = res = pcap_nametoaddrinfo(name);
6170 bpf_error("unknown host '%s'", name);
6173 tproto = tproto6 = proto;
6174 if (off_linktype == -1 && tproto == Q_DEFAULT) {
6178 for (res = res0; res; res = res->ai_next) {
6179 switch (res->ai_family) {
6181 if (tproto == Q_IPV6)
6184 sin4 = (struct sockaddr_in *)
6186 tmp = gen_host(ntohl(sin4->sin_addr.s_addr),
6187 0xffffffff, tproto, dir, q.addr);
6190 if (tproto6 == Q_IP)
6193 sin6 = (struct sockaddr_in6 *)
6195 tmp = gen_host6(&sin6->sin6_addr,
6196 &mask128, tproto6, dir, q.addr);
6208 bpf_error("unknown host '%s'%s", name,
6209 (proto == Q_DEFAULT)
6211 : " for specified address family");
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);
6229 /* override PROTO_UNDEF */
6230 real_proto = IPPROTO_UDP;
6232 if (proto == Q_TCP) {
6233 if (real_proto == IPPROTO_UDP)
6234 bpf_error("port '%s' is udp", name);
6236 else if (real_proto == IPPROTO_SCTP)
6237 bpf_error("port '%s' is sctp", name);
6239 /* override PROTO_UNDEF */
6240 real_proto = IPPROTO_TCP;
6242 if (proto == Q_SCTP) {
6243 if (real_proto == IPPROTO_UDP)
6244 bpf_error("port '%s' is udp", name);
6246 else if (real_proto == IPPROTO_TCP)
6247 bpf_error("port '%s' is tcp", name);
6249 /* override PROTO_UNDEF */
6250 real_proto = IPPROTO_SCTP;
6253 bpf_error("illegal port number %d < 0", port);
6255 bpf_error("illegal port number %d > 65535", port);
6257 return gen_port(port, real_proto, dir);
6259 b = gen_port(port, real_proto, dir);
6260 gen_or(gen_port6(port, real_proto, dir), b);
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);
6276 /* override PROTO_UNDEF */
6277 real_proto = IPPROTO_UDP;
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);
6285 /* override PROTO_UNDEF */
6286 real_proto = IPPROTO_TCP;
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);
6294 /* override PROTO_UNDEF */
6295 real_proto = IPPROTO_SCTP;
6298 bpf_error("illegal port number %d < 0", port1);
6300 bpf_error("illegal port number %d > 65535", port1);
6302 bpf_error("illegal port number %d < 0", port2);
6304 bpf_error("illegal port number %d > 65535", port2);
6307 return gen_portrange(port1, port2, real_proto, dir);
6309 b = gen_portrange(port1, port2, real_proto, dir);
6310 gen_or(gen_portrange6(port1, port2, real_proto, dir), b);
6316 eaddr = pcap_ether_hostton(name);
6318 bpf_error("unknown ether host: %s", name);
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);
6327 bpf_error("'gateway' not supported in this configuration");
6331 real_proto = lookup_proto(name, proto);
6332 if (real_proto >= 0)
6333 return gen_proto(real_proto, proto, dir);
6335 bpf_error("unknown protocol: %s", name);
6338 real_proto = lookup_proto(name, proto);
6339 if (real_proto >= 0)
6340 return gen_protochain(real_proto, proto, dir);
6342 bpf_error("unknown protocol: %s", name);
6353 gen_mcode(s1, s2, masklen, q)
6354 register const char *s1, *s2;
6355 register int masklen;
6358 register int nlen, mlen;
6361 nlen = __pcap_atoin(s1, &n);
6362 /* Promote short ipaddr */
6366 mlen = __pcap_atoin(s2, &m);
6367 /* Promote short ipaddr */
6370 bpf_error("non-network bits set in \"%s mask %s\"",
6373 /* Convert mask len to mask */
6375 bpf_error("mask length must be <= 32");
6378 * X << 32 is not guaranteed by C to be 0; it's
6383 m = 0xffffffff << (32 - masklen);
6385 bpf_error("non-network bits set in \"%s/%d\"",
6392 return gen_host(n, m, q.proto, q.dir, q.addr);
6395 bpf_error("Mask syntax for networks only");
6404 register const char *s;
6409 int proto = q.proto;
6415 else if (q.proto == Q_DECNET)
6416 vlen = __pcap_atodn(s, &v);
6418 vlen = __pcap_atoin(s, &v);
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");
6431 if (s == NULL && q.addr == Q_NET) {
6432 /* Promote short net number */
6433 while (v && (v & 0xff000000) == 0) {
6438 /* Promote short ipaddr */
6442 return gen_host(v, mask, proto, dir, q.addr);
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;
6455 bpf_error("illegal qualifier of 'port'");
6458 bpf_error("illegal port number %u > 65535", v);
6461 return gen_port((int)v, proto, dir);
6465 b = gen_port((int)v, proto, dir);
6466 gen_or(gen_port6((int)v, proto, dir), b);
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;
6481 bpf_error("illegal qualifier of 'portrange'");
6484 bpf_error("illegal port number %u > 65535", v);
6487 return gen_portrange((int)v, (int)v, proto, dir);
6491 b = gen_portrange((int)v, (int)v, proto, dir);
6492 gen_or(gen_portrange6((int)v, (int)v, proto, dir), b);
6498 bpf_error("'gateway' requires a name");
6502 return gen_proto((int)v, proto, dir);
6505 return gen_protochain((int)v, proto, dir);
6520 gen_mcode6(s1, s2, masklen, q)
6521 register const char *s1, *s2;
6522 register int masklen;
6525 struct addrinfo *res;
6526 struct in6_addr *addr;
6527 struct in6_addr mask;
6532 bpf_error("no mask %s supported", s2);
6534 res = pcap_nametoaddrinfo(s1);
6536 bpf_error("invalid ip6 address %s", s1);
6539 bpf_error("%s resolved to multiple address", s1);
6540 addr = &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr;
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);
6547 mask.s6_addr[masklen / 8] =
6548 (0xff << (8 - masklen % 8)) & 0xff;
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);
6563 bpf_error("Mask syntax for networks only");
6567 b = gen_host6(addr, &mask, q.proto, q.dir, q.addr);
6573 bpf_error("invalid qualifier against IPv6 address");
6582 register const u_char *eaddr;
6585 struct block *b, *tmp;
6587 if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) {
6590 case DLT_NETANALYZER:
6591 case DLT_NETANALYZER_TRANSPARENT:
6592 return gen_ehostop(eaddr, (int)q.dir);
6594 return gen_fhostop(eaddr, (int)q.dir);
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:
6602 return gen_wlanhostop(eaddr, (int)q.dir);
6606 * Check that the packet doesn't begin with an
6607 * LE Control marker. (We've already generated
6610 tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
6615 * Now check the MAC address.
6617 b = gen_ehostop(eaddr, (int)q.dir);
6622 case DLT_IP_OVER_FC:
6623 return gen_ipfchostop(eaddr, (int)q.dir);
6625 bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
6629 bpf_error("ethernet address used in non-ether expression");
6636 struct slist *s0, *s1;
6639 * This is definitely not the best way to do this, but the
6640 * lists will rarely get long.
6647 static struct slist *
6653 s = new_stmt(BPF_LDX|BPF_MEM);
6658 static struct slist *
6664 s = new_stmt(BPF_LD|BPF_MEM);
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
6677 gen_load(proto, inst, size)
6682 struct slist *s, *tmp;
6684 int regno = alloc_reg();
6686 free_reg(inst->regno);
6690 bpf_error("data size must be 1, 2, or 4");
6706 bpf_error("unsupported index operation");
6710 * The offset is relative to the beginning of the packet
6711 * data, if we have a radio header. (If we don't, this
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");
6720 * Load into the X register the offset computed into the
6721 * register specified by "index".
6723 s = xfer_to_x(inst);
6726 * Load the item at that offset.
6728 tmp = new_stmt(BPF_LD|BPF_IND|size);
6730 sappend(inst->s, s);
6735 * The offset is relative to the beginning of
6736 * the link-layer header.
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?
6745 s = gen_llprefixlen();
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
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));
6761 s = xfer_to_x(inst);
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).
6770 tmp = new_stmt(BPF_LD|BPF_IND|size);
6773 sappend(inst->s, s);
6789 * The offset is relative to the beginning of
6790 * the network-layer header.
6791 * XXX - are there any cases where we want
6794 s = gen_off_macpl();
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
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));
6810 s = xfer_to_x(inst);
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).
6824 tmp = new_stmt(BPF_LD|BPF_IND|size);
6825 tmp->s.k = off_macpl + off_nl;
6827 sappend(inst->s, s);
6830 * Do the computation only if the packet contains
6831 * the protocol in question.
6833 b = gen_proto_abbrev(proto);
6835 gen_and(inst->b, b);
6849 * The offset is relative to the beginning of
6850 * the transport-layer header.
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.
6856 * XXX - are there any cases where we want
6858 * XXX - we should, if we're built with
6859 * IPv6 support, generate code to load either
6860 * IPv4, IPv6, or both, as appropriate.
6862 s = gen_loadx_iphdrlen();
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.
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.
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);
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.
6893 gen_and(gen_proto_abbrev(proto), b = gen_ipfrag());
6895 gen_and(inst->b, b);
6897 gen_and(gen_proto_abbrev(Q_IP), b);
6903 bpf_error("IPv6 upper-layer protocol is not supported by proto[x]");
6907 inst->regno = regno;
6908 s = new_stmt(BPF_ST);
6910 sappend(inst->s, s);
6916 gen_relation(code, a0, a1, reversed)
6918 struct arth *a0, *a1;
6921 struct slist *s0, *s1, *s2;
6922 struct block *b, *tmp;
6926 if (code == BPF_JEQ) {
6927 s2 = new_stmt(BPF_ALU|BPF_SUB|BPF_X);
6928 b = new_block(JMP(code));
6932 b = new_block(BPF_JMP|code|BPF_X);
6938 sappend(a0->s, a1->s);
6942 free_reg(a0->regno);
6943 free_reg(a1->regno);
6945 /* 'and' together protocol checks */
6948 gen_and(a0->b, tmp = a1->b);
6964 int regno = alloc_reg();
6965 struct arth *a = (struct arth *)newchunk(sizeof(*a));
6968 s = new_stmt(BPF_LD|BPF_LEN);
6969 s->next = new_stmt(BPF_ST);
6970 s->next->s.k = regno;
6985 a = (struct arth *)newchunk(sizeof(*a));
6989 s = new_stmt(BPF_LD|BPF_IMM);
6991 s->next = new_stmt(BPF_ST);
7007 s = new_stmt(BPF_ALU|BPF_NEG);
7010 s = new_stmt(BPF_ST);
7018 gen_arth(code, a0, a1)
7020 struct arth *a0, *a1;
7022 struct slist *s0, *s1, *s2;
7026 s2 = new_stmt(BPF_ALU|BPF_X|code);
7031 sappend(a0->s, a1->s);
7033 free_reg(a0->regno);
7034 free_reg(a1->regno);
7036 s0 = new_stmt(BPF_ST);
7037 a0->regno = s0->s.k = alloc_reg();
7044 * Here we handle simple allocation of the scratch registers.
7045 * If too many registers are alloc'd, the allocator punts.
7047 static int regused[BPF_MEMWORDS];
7051 * Initialize the table of used registers and the current register.
7057 memset(regused, 0, sizeof regused);
7061 * Return the next free register.
7066 int n = BPF_MEMWORDS;
7069 if (regused[curreg])
7070 curreg = (curreg + 1) % BPF_MEMWORDS;
7072 regused[curreg] = 1;
7076 bpf_error("too many registers needed to evaluate expression");
7082 * Return a register to the table so it can
7092 static struct block *
7099 s = new_stmt(BPF_LD|BPF_LEN);
7100 b = new_block(JMP(jmp));
7111 return gen_len(BPF_JGE, n);
7115 * Actually, this is less than or equal.
7123 b = gen_len(BPF_JGT, n);
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.
7140 gen_byteop(op, idx, val)
7151 return gen_cmp(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
7154 b = gen_cmp_lt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
7158 b = gen_cmp_gt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
7162 s = new_stmt(BPF_ALU|BPF_OR|BPF_K);
7166 s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
7170 b = new_block(JMP(BPF_JEQ));
7177 static u_char abroadcast[] = { 0x0 };
7180 gen_broadcast(proto)
7183 bpf_u_int32 hostmask;
7184 struct block *b0, *b1, *b2;
7185 static u_char ebroadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
7193 case DLT_ARCNET_LINUX:
7194 return gen_ahostop(abroadcast, Q_DST);
7196 case DLT_NETANALYZER:
7197 case DLT_NETANALYZER_TRANSPARENT:
7198 return gen_ehostop(ebroadcast, Q_DST);
7200 return gen_fhostop(ebroadcast, Q_DST);
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:
7208 return gen_wlanhostop(ebroadcast, Q_DST);
7209 case DLT_IP_OVER_FC:
7210 return gen_ipfchostop(ebroadcast, Q_DST);
7214 * Check that the packet doesn't begin with an
7215 * LE Control marker. (We've already generated
7218 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS,
7223 * Now check the MAC address.
7225 b0 = gen_ehostop(ebroadcast, Q_DST);
7231 bpf_error("not a broadcast link");
7237 * We treat a netmask of PCAP_NETMASK_UNKNOWN (0xffffffff)
7238 * as an indication that we don't know the netmask, and fail
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);
7252 bpf_error("only link-layer/IP broadcast filters supported");
7258 * Generate code to test the low-order bit of a MAC address (that's
7259 * the bottom bit of the *first* byte).
7261 static struct block *
7262 gen_mac_multicast(offset)
7265 register struct block *b0;
7266 register struct slist *s;
7268 /* link[offset] & 1 != 0 */
7269 s = gen_load_a(OR_LINK, offset, BPF_B);
7270 b0 = new_block(JMP(BPF_JSET));
7277 gen_multicast(proto)
7280 register struct block *b0, *b1, *b2;
7281 register struct slist *s;
7289 case DLT_ARCNET_LINUX:
7290 /* all ARCnet multicasts use the same address */
7291 return gen_ahostop(abroadcast, Q_DST);
7293 case DLT_NETANALYZER:
7294 case DLT_NETANALYZER_TRANSPARENT:
7295 /* ether[0] & 1 != 0 */
7296 return gen_mac_multicast(0);
7299 * XXX TEST THIS: MIGHT NOT PORT PROPERLY XXX
7301 * XXX - was that referring to bit-order issues?
7303 /* fddi[1] & 1 != 0 */
7304 return gen_mac_multicast(1);
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:
7316 * For control frames, there is no DA.
7318 * For management frames, DA is at an
7319 * offset of 4 from the beginning of
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
7330 * Generate the tests to be done for data frames.
7332 * First, check for To DS set, i.e. "link[1] & 0x01".
7334 s = gen_load_a(OR_LINK, 1, BPF_B);
7335 b1 = new_block(JMP(BPF_JSET));
7336 b1->s.k = 0x01; /* To DS */
7340 * If To DS is set, the DA is at 16.
7342 b0 = gen_mac_multicast(16);
7346 * Now, check for To DS not set, i.e. check
7347 * "!(link[1] & 0x01)".
7349 s = gen_load_a(OR_LINK, 1, BPF_B);
7350 b2 = new_block(JMP(BPF_JSET));
7351 b2->s.k = 0x01; /* To DS */
7356 * If To DS is not set, the DA is at 4.
7358 b1 = gen_mac_multicast(4);
7362 * Now OR together the last two checks. That gives
7363 * the complete set of checks for data frames.
7368 * Now check for a data frame.
7369 * I.e, check "link[0] & 0x08".
7371 s = gen_load_a(OR_LINK, 0, BPF_B);
7372 b1 = new_block(JMP(BPF_JSET));
7377 * AND that with the checks done for data frames.
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)".
7386 s = gen_load_a(OR_LINK, 0, BPF_B);
7387 b2 = new_block(JMP(BPF_JSET));
7393 * For management frames, the DA is at 4.
7395 b1 = gen_mac_multicast(4);
7399 * OR that with the checks done for data frames.
7400 * That gives the checks done for management and
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
7411 * I.e., check "!(link[0] & 0x04)".
7413 s = gen_load_a(OR_LINK, 0, BPF_B);
7414 b1 = new_block(JMP(BPF_JSET));
7420 * AND that with the checks for data and management
7425 case DLT_IP_OVER_FC:
7426 b0 = gen_mac_multicast(2);
7431 * Check that the packet doesn't begin with an
7432 * LE Control marker. (We've already generated
7435 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS,
7439 /* ether[off_mac] & 1 != 0 */
7440 b0 = gen_mac_multicast(off_mac);
7448 /* Link not known to support multicasts */
7452 b0 = gen_linktype(ETHERTYPE_IP);
7453 b1 = gen_cmp_ge(OR_NET, 16, BPF_B, (bpf_int32)224);
7459 b0 = gen_linktype(ETHERTYPE_IPV6);
7460 b1 = gen_cmp(OR_NET, 24, BPF_B, (bpf_int32)255);
7465 bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel");
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".
7479 register struct block *b0;
7482 * Only some data link types support inbound/outbound qualifiers.
7486 b0 = gen_relation(BPF_JEQ,
7487 gen_load(Q_LINK, gen_loadi(0), 1),
7494 /* match outgoing packets */
7495 b0 = gen_cmp(OR_LINK, 2, BPF_H, IPNET_OUTBOUND);
7497 /* match incoming packets */
7498 b0 = gen_cmp(OR_LINK, 2, BPF_H, IPNET_INBOUND);
7505 * Match packets sent by this machine.
7507 b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_OUTGOING);
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.)
7515 * XXX - packets sent to other machines probably
7516 * shouldn't be matched, but what about broadcast
7517 * or multicast packets we received?
7519 b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_HOST);
7523 #ifdef HAVE_NET_PFVAR_H
7525 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, dir), BPF_B,
7526 (bpf_int32)((dir == 0) ? PF_IN : PF_OUT));
7532 /* match outgoing packets */
7533 b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_OUT);
7535 /* match incoming packets */
7536 b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_IN);
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:
7563 /* juniper flags (including direction) are stored
7564 * the byte after the 3-byte magic number */
7566 /* match outgoing packets */
7567 b0 = gen_mcmp(OR_LINK, 3, BPF_B, 0, 0x01);
7569 /* match incoming packets */
7570 b0 = gen_mcmp(OR_LINK, 3, BPF_B, 1, 0x01);
7575 bpf_error("inbound/outbound not supported on linktype %d",
7583 #ifdef HAVE_NET_PFVAR_H
7584 /* PF firewall log matched interface */
7586 gen_pf_ifname(const char *ifname)
7591 if (linktype != DLT_PFLOG) {
7592 bpf_error("ifname supported only on PF linktype");
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",
7602 b0 = gen_bcmp(OR_LINK, off, strlen(ifname), (const u_char *)ifname);
7606 /* PF firewall log ruleset name */
7608 gen_pf_ruleset(char *ruleset)
7612 if (linktype != DLT_PFLOG) {
7613 bpf_error("ruleset supported only on PF linktype");
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));
7623 b0 = gen_bcmp(OR_LINK, offsetof(struct pfloghdr, ruleset),
7624 strlen(ruleset), (const u_char *)ruleset);
7628 /* PF firewall log rule number */
7634 if (linktype != DLT_PFLOG) {
7635 bpf_error("rnr supported only on PF linktype");
7639 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, rulenr), BPF_W,
7644 /* PF firewall log sub-rule number */
7646 gen_pf_srnr(int srnr)
7650 if (linktype != DLT_PFLOG) {
7651 bpf_error("srnr supported only on PF linktype");
7655 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, subrulenr), BPF_W,
7660 /* PF firewall log reason code */
7662 gen_pf_reason(int reason)
7666 if (linktype != DLT_PFLOG) {
7667 bpf_error("reason supported only on PF linktype");
7671 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, reason), BPF_B,
7676 /* PF firewall log action */
7678 gen_pf_action(int action)
7682 if (linktype != DLT_PFLOG) {
7683 bpf_error("action supported only on PF linktype");
7687 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, action), BPF_B,
7691 #else /* !HAVE_NET_PFVAR_H */
7693 gen_pf_ifname(const char *ifname)
7695 bpf_error("libpcap was compiled without pf support");
7701 gen_pf_ruleset(char *ruleset)
7703 bpf_error("libpcap was compiled on a machine without pf support");
7711 bpf_error("libpcap was compiled on a machine without pf support");
7717 gen_pf_srnr(int srnr)
7719 bpf_error("libpcap was compiled on a machine without pf support");
7725 gen_pf_reason(int reason)
7727 bpf_error("libpcap was compiled on a machine without pf support");
7733 gen_pf_action(int action)
7735 bpf_error("libpcap was compiled on a machine without pf support");
7739 #endif /* HAVE_NET_PFVAR_H */
7741 /* IEEE 802.11 wireless header */
7743 gen_p80211_type(int type, int mask)
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,
7758 bpf_error("802.11 link-layer types supported only on 802.11");
7766 gen_p80211_fcdir(int fcdir)
7772 case DLT_IEEE802_11:
7773 case DLT_PRISM_HEADER:
7774 case DLT_IEEE802_11_RADIO_AVS:
7775 case DLT_IEEE802_11_RADIO:
7779 bpf_error("frame direction supported only with 802.11 headers");
7783 b0 = gen_mcmp(OR_LINK, 1, BPF_B, (bpf_int32)fcdir,
7784 (bpf_u_int32)IEEE80211_FC1_DIR_MASK);
7791 register const u_char *eaddr;
7797 case DLT_ARCNET_LINUX:
7798 if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) &&
7800 return (gen_ahostop(eaddr, (int)q.dir));
7802 bpf_error("ARCnet address used in non-arc expression");
7808 bpf_error("aid supported only on ARCnet");
7811 bpf_error("ARCnet address used in non-arc expression");
7816 static struct block *
7817 gen_ahostop(eaddr, dir)
7818 register const u_char *eaddr;
7821 register struct block *b0, *b1;
7824 /* src comes first, different from Ethernet */
7826 return gen_bcmp(OR_LINK, 0, 1, eaddr);
7829 return gen_bcmp(OR_LINK, 1, 1, eaddr);
7832 b0 = gen_ahostop(eaddr, Q_SRC);
7833 b1 = gen_ahostop(eaddr, Q_DST);
7839 b0 = gen_ahostop(eaddr, Q_SRC);
7840 b1 = gen_ahostop(eaddr, Q_DST);
7845 bpf_error("'addr1' is only supported on 802.11");
7849 bpf_error("'addr2' is only supported on 802.11");
7853 bpf_error("'addr3' is only supported on 802.11");
7857 bpf_error("'addr4' is only supported on 802.11");
7861 bpf_error("'ra' is only supported on 802.11");
7865 bpf_error("'ta' is only supported on 802.11");
7873 * support IEEE 802.1Q VLAN trunk over ethernet
7879 struct block *b0, *b1;
7881 /* can't check for VLAN-encapsulated packets inside MPLS */
7882 if (label_stack_depth > 0)
7883 bpf_error("no VLAN match after MPLS");
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
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.
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...".
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);
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);
7948 bpf_error("no VLAN support for data link type %d",
7963 struct block *b0,*b1;
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
7972 * XXX - this is a bit of a kludge. See comments in gen_vlan().
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);
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
7988 case DLT_C_HDLC: /* fall through */
7990 case DLT_NETANALYZER:
7991 case DLT_NETANALYZER_TRANSPARENT:
7992 b0 = gen_linktype(ETHERTYPE_MPLS);
7996 b0 = gen_linktype(PPP_MPLS_UCAST);
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 */
8004 bpf_error("no MPLS support for data link type %d",
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 */
8023 label_stack_depth++;
8028 * Support PPPOE discovery and session.
8033 /* check for PPPoE discovery */
8034 return gen_linktype((bpf_int32)ETHERTYPE_PPPOED);
8043 * Test against the PPPoE session link-layer type.
8045 b0 = gen_linktype((bpf_int32)ETHERTYPE_PPPOES);
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
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.
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...".
8076 orig_linktype = off_linktype; /* save original values */
8081 * The "network-layer" protocol is PPPoE, which has a 6-byte
8082 * PPPoE header, followed by a PPP packet.
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.
8091 off_linktype = off_nl + 6;
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.
8099 off_nl_nosnap = 6+2;
8105 gen_atmfield_code(atmfield, jvalue, jtype, reverse)
8117 bpf_error("'vpi' supported only on raw ATM");
8118 if (off_vpi == (u_int)-1)
8120 b0 = gen_ncmp(OR_LINK, off_vpi, BPF_B, 0xffffffff, jtype,
8126 bpf_error("'vci' supported only on raw ATM");
8127 if (off_vci == (u_int)-1)
8129 b0 = gen_ncmp(OR_LINK, off_vci, BPF_H, 0xffffffff, jtype,
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,
8141 if (off_payload == (u_int)-1)
8143 b0 = gen_ncmp(OR_LINK, off_payload + MSG_TYPE_POS, BPF_B,
8144 0xffffffff, jtype, reverse, jvalue);
8149 bpf_error("'callref' supported only on raw ATM");
8150 if (off_proto == (u_int)-1)
8152 b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0xffffffff,
8153 jtype, reverse, jvalue);
8163 gen_atmtype_abbrev(type)
8166 struct block *b0, *b1;
8171 /* Get all packets in Meta signalling Circuit */
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);
8180 /* Get all packets in Broadcast Circuit*/
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);
8189 /* Get all cells in Segment OAM F4 circuit*/
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);
8198 /* Get all cells in End-to-End OAM F4 Circuit*/
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);
8207 /* Get all packets in connection Signalling Circuit */
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);
8216 /* Get all packets in ILMI Circuit */
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);
8225 /* Get all LANE packets */
8227 bpf_error("'lane' supported only on raw ATM");
8228 b1 = gen_atmfield_code(A_PROTOTYPE, PT_LANE, BPF_JEQ, 0);
8231 * Arrange that all subsequent tests assume LANE
8232 * rather than LLC-encapsulated packets, and set
8233 * the offsets appropriately for LANE-encapsulated
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".
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 */
8251 /* Get all LLC-encapsulated packets */
8253 bpf_error("'llc' supported only on raw ATM");
8254 b1 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
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
8271 gen_mtp2type_abbrev(type)
8274 struct block *b0, *b1;
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);
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);
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);
8312 gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
8319 bpf_u_int32 val1 , val2 , val3;
8321 switch (mtp3field) {
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 */
8328 bpf_error("sio value %u too big; max value = 255",
8330 b0 = gen_ncmp(OR_PACKET, off_sio, BPF_B, 0xffffffff,
8331 (u_int)jtype, reverse, (u_int)jvalue);
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 */
8339 bpf_error("opc value %u too big; max value = 16383",
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;
8345 val2 = jvalue & 0x000003fc;
8347 val3 = jvalue & 0x00000003;
8349 jvalue = val1 + val2 + val3;
8350 b0 = gen_ncmp(OR_PACKET, off_opc, BPF_W, 0x00c0ff0f,
8351 (u_int)jtype, reverse, (u_int)jvalue);
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 */
8359 bpf_error("dpc value %u too big; max value = 16383",
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;
8365 val2 = jvalue & 0x00003f00;
8367 jvalue = val1 + val2;
8368 b0 = gen_ncmp(OR_PACKET, off_dpc, BPF_W, 0xff3f0000,
8369 (u_int)jtype, reverse, (u_int)jvalue);
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 */
8377 bpf_error("sls value %u too big; max value = 15",
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);
8392 static struct block *
8393 gen_msg_abbrev(type)
8399 * Q.2931 signalling protocol messages for handling virtual circuits
8400 * establishment and teardown
8405 b1 = gen_atmfield_code(A_MSGTYPE, SETUP, BPF_JEQ, 0);
8409 b1 = gen_atmfield_code(A_MSGTYPE, CALL_PROCEED, BPF_JEQ, 0);
8413 b1 = gen_atmfield_code(A_MSGTYPE, CONNECT, BPF_JEQ, 0);
8417 b1 = gen_atmfield_code(A_MSGTYPE, CONNECT_ACK, BPF_JEQ, 0);
8421 b1 = gen_atmfield_code(A_MSGTYPE, RELEASE, BPF_JEQ, 0);
8424 case A_RELEASE_DONE:
8425 b1 = gen_atmfield_code(A_MSGTYPE, RELEASE_DONE, BPF_JEQ, 0);
8435 gen_atmmulti_abbrev(type)
8438 struct block *b0, *b1;
8444 bpf_error("'oam' supported only on raw ATM");
8445 b1 = gen_atmmulti_abbrev(A_OAMF4);
8450 bpf_error("'oamf4' supported only on raw ATM");
8452 b0 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0);
8453 b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0);
8455 b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
8461 * Get Q.2931 signalling messages for switched
8462 * virtual connection
8465 bpf_error("'connectmsg' supported only on raw ATM");
8466 b0 = gen_msg_abbrev(A_SETUP);
8467 b1 = gen_msg_abbrev(A_CALLPROCEED);
8469 b0 = gen_msg_abbrev(A_CONNECT);
8471 b0 = gen_msg_abbrev(A_CONNECTACK);
8473 b0 = gen_msg_abbrev(A_RELEASE);
8475 b0 = gen_msg_abbrev(A_RELEASE_DONE);
8477 b0 = gen_atmtype_abbrev(A_SC);
8483 bpf_error("'metaconnect' supported only on raw ATM");
8484 b0 = gen_msg_abbrev(A_SETUP);
8485 b1 = gen_msg_abbrev(A_CALLPROCEED);
8487 b0 = gen_msg_abbrev(A_CONNECT);
8489 b0 = gen_msg_abbrev(A_RELEASE);
8491 b0 = gen_msg_abbrev(A_RELEASE_DONE);
8493 b0 = gen_atmtype_abbrev(A_METAC);