1/*#define CHASE_CHAIN*/
2/*
3 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998
4 * The Regents of the University of California. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that: (1) source code distributions
8 * retain the above copyright notice and this paragraph in its entirety, (2)
--- 5 unchanged lines hidden (view full) ---
14 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
15 * the University nor the names of its contributors may be used to endorse
16 * or promote products derived from this software without specific prior
17 * written permission.
18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
19 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
21 *
22 * $FreeBSD: head/contrib/libpcap/gencode.c 147897 2005-07-11 03:43:25Z sam $
23 */
24#ifndef lint
25static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.24 2005/06/20 21:52:53 guy Exp $ (LBL)";
27#endif
28
29#ifdef HAVE_CONFIG_H
30#include "config.h"
31#endif
32
33#ifdef WIN32
34#include <pcap-stdinc.h>
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99
100#define JMP(c) ((c)|BPF_JMP|BPF_K)
101
102/* Locals */
103static jmp_buf top_ctx;
104static pcap_t *bpf_pcap;
105
106/* Hack for updating VLAN, MPLS offsets. */
107static u_int orig_linktype = -1U, orig_nl = -1U;
108
109/* XXX */
110#ifdef PCAP_FDDIPAD
111static int pcap_fddipad;
112#endif
113
114/* VARARGS */
115void
116bpf_error(const char *fmt, ...)
117{
118 va_list ap;
119
120 va_start(ap, fmt);
121 if (bpf_pcap != NULL)
122 (void)vsnprintf(pcap_geterr(bpf_pcap), PCAP_ERRBUF_SIZE,
123 fmt, ap);
124 va_end(ap);
--- 4 unchanged lines hidden (view full) ---
129static void init_linktype(pcap_t *);
130
131static int alloc_reg(void);
132static void free_reg(int);
133
134static struct block *root;
135
136/*
137 * Value passed to gen_load_a() to indicate what the offset argument
138 * is relative to.
139 */
140enum e_offrel {
141 OR_PACKET, /* relative to the beginning of the packet */
142 OR_LINK, /* relative to the link-layer header */
143 OR_NET, /* relative to the network-layer header */
144 OR_NET_NOSNAP, /* relative to the network-layer header, with no SNAP header at the link layer */
145 OR_TRAN_IPV4, /* relative to the transport-layer header, with IPv4 network layer */
146 OR_TRAN_IPV6 /* relative to the transport-layer header, with IPv6 network layer */
147};
148
149/*
150 * We divy out chunks of memory rather than call malloc each time so
151 * we don't have to worry about leaking memory. It's probably
152 * not a big deal if all this memory was wasted but if this ever
153 * goes into a library that would probably not be a good idea.
154 *
155 * XXX - this *is* in a library....
156 */
157#define NCHUNKS 16
--- 10 unchanged lines hidden (view full) ---
168static void freechunks(void);
169static inline struct block *new_block(int);
170static inline struct slist *new_stmt(int);
171static struct block *gen_retblk(int);
172static inline void syntax(void);
173
174static void backpatch(struct block *, struct block *);
175static void merge(struct block *, struct block *);
176static struct block *gen_cmp(enum e_offrel, u_int, u_int, bpf_int32);
177static struct block *gen_cmp_gt(enum e_offrel, u_int, u_int, bpf_int32);
178static struct block *gen_cmp_ge(enum e_offrel, u_int, u_int, bpf_int32);
179static struct block *gen_cmp_lt(enum e_offrel, u_int, u_int, bpf_int32);
180static struct block *gen_cmp_le(enum e_offrel, u_int, u_int, bpf_int32);
181static struct block *gen_mcmp(enum e_offrel, u_int, u_int, bpf_int32,
182 bpf_u_int32);
183static struct block *gen_bcmp(enum e_offrel, u_int, u_int, const u_char *);
184static struct block *gen_ncmp(enum e_offrel, bpf_u_int32, bpf_u_int32,
185 bpf_u_int32, bpf_u_int32, int, bpf_int32);
186static struct slist *gen_load_llrel(u_int, u_int);
187static struct slist *gen_load_a(enum e_offrel, u_int, u_int);
188static struct slist *gen_loadx_iphdrlen(void);
189static struct block *gen_uncond(int);
190static inline struct block *gen_true(void);
191static inline struct block *gen_false(void);
192static struct block *gen_ether_linktype(int);
193static struct block *gen_linux_sll_linktype(int);
194static void insert_radiotap_load_llprefixlen(struct block *);
195static void insert_load_llprefixlen(struct block *);
196static struct slist *gen_llprefixlen(void);
197static struct block *gen_linktype(int);
198static struct block *gen_snap(bpf_u_int32, bpf_u_int32, u_int);
199static struct block *gen_llc_linktype(int);
200static struct block *gen_hostop(bpf_u_int32, bpf_u_int32, int, int, u_int, u_int);
201#ifdef INET6
202static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int);
203#endif
204static struct block *gen_ahostop(const u_char *, int);
205static struct block *gen_ehostop(const u_char *, int);
206static struct block *gen_fhostop(const u_char *, int);
207static struct block *gen_thostop(const u_char *, int);
208static struct block *gen_wlanhostop(const u_char *, int);
209static struct block *gen_ipfchostop(const u_char *, int);
210static struct block *gen_dnhostop(bpf_u_int32, int);
211static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int);
212#ifdef INET6
213static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int);
214#endif
215#ifndef INET6
216static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int);
217#endif
218static struct block *gen_ipfrag(void);
219static struct block *gen_portatom(int, bpf_int32);
220static struct block *gen_portrangeatom(int, bpf_int32, bpf_int32);
221#ifdef INET6
222static struct block *gen_portatom6(int, bpf_int32);
223static struct block *gen_portrangeatom6(int, bpf_int32, bpf_int32);
224#endif
225struct block *gen_portop(int, int, int);
226static struct block *gen_port(int, int, int);
227struct block *gen_portrangeop(int, int, int, int);
228static struct block *gen_portrange(int, int, int, int);
229#ifdef INET6
230struct block *gen_portop6(int, int, int);
231static struct block *gen_port6(int, int, int);
232struct block *gen_portrangeop6(int, int, int, int);
233static struct block *gen_portrange6(int, int, int, int);
234#endif
235static int lookup_proto(const char *, int);
236static struct block *gen_protochain(int, int, int);
237static struct block *gen_proto(int, int, int);
238static struct slist *xfer_to_x(struct arth *);
239static struct slist *xfer_to_a(struct arth *);
240static struct block *gen_mac_multicast(int);
241static struct block *gen_len(int, int);
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477void
478finish_parse(p)
479 struct block *p;
480{
481 backpatch(p, gen_retblk(snaplen));
482 p->sense = !p->sense;
483 backpatch(p, gen_retblk(0));
484 root = p->head;
485
486 /*
487 * Insert before the statements of the first (root) block any
488 * statements needed to load the lengths of any variable-length
489 * headers into registers.
490 *
491 * XXX - a fancier strategy would be to insert those before the
492 * statements of all blocks that use those lengths and that
493 * have no predecessors that use them, so that we only compute
494 * the lengths if we need them. There might be even better
495 * approaches than that. However, as we're currently only
496 * handling variable-length radiotap headers, and as all
497 * filtering expressions other than raw link[M:N] tests
498 * require the length of that header, doing more for that
499 * header length isn't really worth the effort.
500 */
501 insert_load_llprefixlen(root);
502}
503
504void
505gen_and(b0, b1)
506 struct block *b0, *b1;
507{
508 backpatch(b0, b1->head);
509 b0->sense = !b0->sense;
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527void
528gen_not(b)
529 struct block *b;
530{
531 b->sense = !b->sense;
532}
533
534static struct block *
535gen_cmp(offrel, offset, size, v)
536 enum e_offrel offrel;
537 u_int offset, size;
538 bpf_int32 v;
539{
540 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JEQ, 0, v);
541}
542
543static struct block *
544gen_cmp_gt(offrel, offset, size, v)
545 enum e_offrel offrel;
546 u_int offset, size;
547 bpf_int32 v;
548{
549 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 0, v);
550}
551
552static struct block *
553gen_cmp_ge(offrel, offset, size, v)
554 enum e_offrel offrel;
555 u_int offset, size;
556 bpf_int32 v;
557{
558 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 0, v);
559}
560
561static struct block *
562gen_cmp_lt(offrel, offset, size, v)
563 enum e_offrel offrel;
564 u_int offset, size;
565 bpf_int32 v;
566{
567 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 1, v);
568}
569
570static struct block *
571gen_cmp_le(offrel, offset, size, v)
572 enum e_offrel offrel;
573 u_int offset, size;
574 bpf_int32 v;
575{
576 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 1, v);
577}
578
579static struct block *
580gen_mcmp(offrel, offset, size, v, mask)
581 enum e_offrel offrel;
582 u_int offset, size;
583 bpf_int32 v;
584 bpf_u_int32 mask;
585{
586 return gen_ncmp(offrel, offset, size, mask, BPF_JEQ, 0, v);
587}
588
589static struct block *
590gen_bcmp(offrel, offset, size, v)
591 enum e_offrel offrel;
592 register u_int offset, size;
593 register const u_char *v;
594{
595 register struct block *b, *tmp;
596
597 b = NULL;
598 while (size >= 4) {
599 register const u_char *p = &v[size - 4];
600 bpf_int32 w = ((bpf_int32)p[0] << 24) |
601 ((bpf_int32)p[1] << 16) | ((bpf_int32)p[2] << 8) | p[3];
602
603 tmp = gen_cmp(offrel, offset + size - 4, BPF_W, w);
604 if (b != NULL)
605 gen_and(b, tmp);
606 b = tmp;
607 size -= 4;
608 }
609 while (size >= 2) {
610 register const u_char *p = &v[size - 2];
611 bpf_int32 w = ((bpf_int32)p[0] << 8) | p[1];
612
613 tmp = gen_cmp(offrel, offset + size - 2, BPF_H, w);
614 if (b != NULL)
615 gen_and(b, tmp);
616 b = tmp;
617 size -= 2;
618 }
619 if (size > 0) {
620 tmp = gen_cmp(offrel, offset, BPF_B, (bpf_int32)v[0]);
621 if (b != NULL)
622 gen_and(b, tmp);
623 b = tmp;
624 }
625 return b;
626}
627
628/*
629 * AND the field of size "size" at offset "offset" relative to the header
630 * specified by "offrel" with "mask", and compare it with the value "v"
631 * with the test specified by "jtype"; if "reverse" is true, the test
632 * should test the opposite of "jtype".
633 */
634static struct block *
635gen_ncmp(offrel, offset, size, mask, jtype, reverse, v)
636 enum e_offrel offrel;
637 bpf_int32 v;
638 bpf_u_int32 offset, size, mask, jtype;
639 int reverse;
640{
641 struct slist *s, *s2;
642 struct block *b;
643
644 s = gen_load_a(offrel, offset, size);
645
646 if (mask != 0xffffffff) {
647 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
648 s2->s.k = mask;
649 sappend(s, s2);
650 }
651
652 b = new_block(JMP(jtype));
653 b->stmts = s;
654 b->s.k = v;
655 if (reverse && (jtype == BPF_JGT || jtype == BPF_JGE))
656 gen_not(b);
657 return b;
658}
659
660/*
661 * Various code constructs need to know the layout of the data link
662 * layer. These variables give the necessary offsets from the beginning
663 * of the packet data.
664 *
665 * If the link layer has variable_length headers, the offsets are offsets
666 * from the end of the link-link-layer header, and "reg_ll_size" is
667 * the register number for a register containing the length of the
668 * link-layer header. Otherwise, "reg_ll_size" is -1.
669 */
670static int reg_ll_size;
671
672/*
673 * This is the offset of the beginning of the link-layer header.
674 * It's usually 0, except for 802.11 with a fixed-length radio header.
675 */
676static u_int off_ll;
677
678/*
679 * This is the offset of the beginning of the MAC-layer header.
680 * It's usually 0, except for ATM LANE.
681 */
682static u_int off_mac;
683
684/*
685 * "off_linktype" is the offset to information in the link-layer header
686 * giving the packet type.
--- 29 unchanged lines hidden (view full) ---
716/*
717 * These are offsets for the ATM pseudo-header.
718 */
719static u_int off_vpi;
720static u_int off_vci;
721static u_int off_proto;
722
723/*
724 * These are offsets for the MTP3 fields.
725 */
726static u_int off_sio;
727static u_int off_opc;
728static u_int off_dpc;
729static u_int off_sls;
730
731/*
732 * This is the offset of the first byte after the ATM pseudo_header,
733 * or -1 if there is no ATM pseudo-header.
734 */
735static u_int off_payload;
736
737/*
738 * These are offsets to the beginning of the network-layer header.
739 *
--- 36 unchanged lines hidden (view full) ---
776 off_mac = 0;
777 is_atm = 0;
778 is_lane = 0;
779 off_vpi = -1;
780 off_vci = -1;
781 off_proto = -1;
782 off_payload = -1;
783
784 off_sio = -1;
785 off_opc = -1;
786 off_dpc = -1;
787 off_sls = -1;
788
789 /*
790 * Also assume it's not 802.11 with a fixed-length radio header.
791 */
792 off_ll = 0;
793
794 orig_linktype = -1;
795 orig_nl = -1;
796
797 reg_ll_size = -1;
798
799 switch (linktype) {
800
801 case DLT_ARCNET:
802 off_linktype = 2;
803 off_nl = 6; /* XXX in reality, variable! */
804 off_nl_nosnap = 6; /* no 802.2 LLC */
805 return;
806
--- 141 unchanged lines hidden (view full) ---
948 * the 802.11 header, containing a bunch of additional
949 * information including radio-level information.
950 *
951 * The header is 144 bytes long.
952 *
953 * XXX - same variable-length header problem; at least
954 * the Prism header is fixed-length.
955 */
956 off_ll = 144;
957 off_linktype = 144+24;
958 off_nl = 144+32; /* Prism+802.11+802.2+SNAP */
959 off_nl_nosnap = 144+27; /* Prism+802.11+802.2 */
960 return;
961
962 case DLT_IEEE802_11_RADIO_AVS:
963 /*
964 * Same as 802.11, but with an additional header before
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969 * current incarnation.
970 *
971 * XXX - same variable-length header problem, only
972 * more so; this header is also variable-length,
973 * with the length being the 32-bit big-endian
974 * number at an offset of 4 from the beginning
975 * of the radio header.
976 */
977 off_ll = 64;
978 off_linktype = 64+24;
979 off_nl = 64+32; /* Radio+802.11+802.2+SNAP */
980 off_nl_nosnap = 64+27; /* Radio+802.11+802.2 */
981 return;
982
983 case DLT_IEEE802_11_RADIO:
984 /*
985 * Same as 802.11, but with an additional header before
986 * the 802.11 header, containing a bunch of additional
987 * information including radio-level information.
988 *
989 * The radiotap header is variable length, and we
990 * generate code to compute its length and store it
991 * in a register. These offsets are relative to the
992 * beginning of the 802.11 header.
993 */
994 off_linktype = 24;
995 off_nl = 32; /* 802.11+802.2+SNAP */
996 off_nl_nosnap = 27; /* 802.11+802.2 */
997 return;
998
999 case DLT_ATM_RFC1483:
1000 case DLT_ATM_CLIP: /* Linux ATM defines this */
1001 /*
1002 * assume routed, non-ISO PDUs
1003 * (i.e., LLC = 0xAA-AA-03, OUT = 0x00-00-00)
1004 *
1005 * XXX - what about ISO PDUs, e.g. CLNP, ISIS, ESIS,
1006 * or PPP with the PPP NLPID (e.g., PPPoA)? The
1007 * latter would presumably be treated the way PPPoE
1008 * should be, so you can do "pppoe and udp port 2049"
1009 * or "pppoa and tcp port 80" and have it check for
1010 * PPPo{A,E} and a PPP protocol of IP and....
1011 */
1012 off_linktype = 0;
1013 off_nl = 8; /* 802.2+SNAP */
1014 off_nl_nosnap = 3; /* 802.2 */
1015 return;
1016
1017 case DLT_SUNATM:
1018 /*
--- 58 unchanged lines hidden (view full) ---
1077 off_linktype = -1;
1078 off_nl = 0;
1079 off_nl_nosnap = 0; /* no 802.2 LLC */
1080 return;
1081
1082 case DLT_APPLE_IP_OVER_IEEE1394:
1083 off_linktype = 16;
1084 off_nl = 18;
1085 off_nl_nosnap = 18; /* no 802.2 LLC */
1086 return;
1087
1088 case DLT_LINUX_IRDA:
1089 /*
1090 * Currently, only raw "link[N:M]" filtering is supported.
1091 */
1092 off_linktype = -1;
1093 off_nl = -1;
--- 12 unchanged lines hidden (view full) ---
1106 case DLT_SYMANTEC_FIREWALL:
1107 off_linktype = 6;
1108 off_nl = 44; /* Ethernet II */
1109 off_nl_nosnap = 44; /* XXX - what does it do with 802.3 packets? */
1110 return;
1111
1112 case DLT_PFLOG:
1113 off_linktype = 0;
1114 /* XXX read this from pf.h? */
1115 off_nl = PFLOG_HDRLEN;
1116 off_nl_nosnap = PFLOG_HDRLEN; /* no 802.2 LLC */
1117 return;
1118
1119 case DLT_JUNIPER_MLFR:
1120 case DLT_JUNIPER_MLPPP:
1121 off_linktype = 4;
1122 off_nl = 4;
1123 off_nl_nosnap = -1; /* no 802.2 LLC */
1124 return;
1125
1126 case DLT_JUNIPER_ATM1:
1127 off_linktype = 4; /* in reality variable between 4-8 */
1128 off_nl = 4;
1129 off_nl_nosnap = 14;
1130 return;
1131
1132 case DLT_JUNIPER_ATM2:
1133 off_linktype = 8; /* in reality variable between 8-12 */
1134 off_nl = 8;
1135 off_nl_nosnap = 18;
1136 return;
1137
1138 /* frames captured on a Juniper PPPoE service PIC
1139 * contain raw ethernet frames */
1140 case DLT_JUNIPER_PPPOE:
1141 off_linktype = 16;
1142 off_nl = 18; /* Ethernet II */
1143 off_nl_nosnap = 21; /* 802.3+802.2 */
1144 return;
1145
1146 case DLT_JUNIPER_PPPOE_ATM:
1147 off_linktype = 4;
1148 off_nl = 6;
1149 off_nl_nosnap = -1; /* no 802.2 LLC */
1150 return;
1151
1152 case DLT_JUNIPER_GGSN:
1153 off_linktype = 6;
1154 off_nl = 12;
1155 off_nl_nosnap = -1; /* no 802.2 LLC */
1156 return;
1157
1158 case DLT_JUNIPER_ES:
1159 off_linktype = 6;
1160 off_nl = -1; /* not really a network layer but raw IP adresses */
1161 off_nl_nosnap = -1; /* no 802.2 LLC */
1162 return;
1163
1164 case DLT_JUNIPER_MONITOR:
1165 off_linktype = 12;
1166 off_nl = 12; /* raw IP/IP6 header */
1167 off_nl_nosnap = -1; /* no 802.2 LLC */
1168 return;
1169
1170 case DLT_JUNIPER_SERVICES:
1171 off_linktype = 12;
1172 off_nl = -1; /* L3 proto location dep. on cookie type */
1173 off_nl_nosnap = -1; /* no 802.2 LLC */
1174 return;
1175
1176 case DLT_MTP2:
1177 off_sio = 3;
1178 off_opc = 4;
1179 off_dpc = 4;
1180 off_sls = 7;
1181 off_linktype = -1;
1182 off_nl = -1;
1183 off_nl_nosnap = -1;
1184 return;
1185
1186#ifdef DLT_PFSYNC
1187 case DLT_PFSYNC:
1188 off_linktype = -1;
1189 off_nl = 4;
1190 off_nl_nosnap = 4;
1191 return;
1192#endif
1193
1194 case DLT_LINUX_LAPD:
1195 /*
1196 * Currently, only raw "link[N:M]" filtering is supported.
1197 */
1198 off_linktype = -1;
1199 off_nl = -1;
1200 off_nl_nosnap = -1;
1201 return;
1202 }
1203 bpf_error("unknown data link type %d", linktype);
1204 /* NOTREACHED */
1205}
1206
1207/*
1208 * Load a value relative to the beginning of the link-layer header.
1209 * The link-layer header doesn't necessarily begin at the beginning
1210 * of the packet data; there might be a variable-length prefix containing
1211 * radio information.
1212 */
1213static struct slist *
1214gen_load_llrel(offset, size)
1215 u_int offset, size;
1216{
1217 struct slist *s, *s2;
1218
1219 s = gen_llprefixlen();
1220
1221 /*
1222 * If "s" is non-null, it has code to arrange that the X register
1223 * contains the length of the prefix preceding the link-layer
1224 * header.
1225 */
1226 if (s != NULL) {
1227 s2 = new_stmt(BPF_LD|BPF_IND|size);
1228 s2->s.k = offset;
1229 sappend(s, s2);
1230 } else {
1231 s = new_stmt(BPF_LD|BPF_ABS|size);
1232 s->s.k = offset;
1233 }
1234 return s;
1235}
1236
1237/*
1238 * Load a value relative to the beginning of the specified header.
1239 */
1240static struct slist *
1241gen_load_a(offrel, offset, size)
1242 enum e_offrel offrel;
1243 u_int offset, size;
1244{
1245 struct slist *s, *s2;
1246
1247 switch (offrel) {
1248
1249 case OR_PACKET:
1250 s = gen_load_llrel(offset, size);
1251 break;
1252
1253 case OR_LINK:
1254 s = gen_load_llrel(off_ll + offset, size);
1255 break;
1256
1257 case OR_NET:
1258 s = gen_load_llrel(off_nl + offset, size);
1259 break;
1260
1261 case OR_NET_NOSNAP:
1262 s = gen_load_llrel(off_nl_nosnap + offset, size);
1263 break;
1264
1265 case OR_TRAN_IPV4:
1266 /*
1267 * Load the X register with the length of the IPv4 header,
1268 * in bytes.
1269 */
1270 s = gen_loadx_iphdrlen();
1271
1272 /*
1273 * Load the item at {length of the link-layer header} +
1274 * {length of the IPv4 header} + {specified offset}.
1275 */
1276 s2 = new_stmt(BPF_LD|BPF_IND|size);
1277 s2->s.k = off_nl + offset;
1278 sappend(s, s2);
1279 break;
1280
1281 case OR_TRAN_IPV6:
1282 s = gen_load_llrel(off_nl + 40 + offset, size);
1283 break;
1284
1285 default:
1286 abort();
1287 return NULL;
1288 }
1289 return s;
1290}
1291
1292/*
1293 * Generate code to load into the X register the sum of the length of
1294 * the IPv4 header and any variable-length header preceding the link-layer
1295 * header.
1296 */
1297static struct slist *
1298gen_loadx_iphdrlen()
1299{
1300 struct slist *s, *s2;
1301
1302 s = gen_llprefixlen();
1303 if (s != NULL) {
1304 /*
1305 * There's a variable-length prefix preceding the
1306 * link-layer header. "s" points to a list of statements
1307 * that put the length of that prefix into the X register.
1308 * The 4*([k]&0xf) addressing mode can't be used, as we
1309 * don't have a constant offset, so we have to load the
1310 * value in question into the A register and add to it
1311 * the value from the X register.
1312 */
1313 s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
1314 s2->s.k = off_nl;
1315 sappend(s, s2);
1316 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
1317 s2->s.k = 0xf;
1318 sappend(s, s2);
1319 s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
1320 s2->s.k = 2;
1321 sappend(s, s2);
1322
1323 /*
1324 * The A register now contains the length of the
1325 * IP header. We need to add to it the length
1326 * of the prefix preceding the link-layer
1327 * header, which is still in the X register, and
1328 * move the result into the X register.
1329 */
1330 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
1331 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
1332 } else {
1333 /*
1334 * There is no variable-length header preceding the
1335 * link-layer header; if there's a fixed-length
1336 * header preceding it, its length is included in
1337 * the off_ variables, so it doesn't need to be added.
1338 */
1339 s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
1340 s->s.k = off_nl;
1341 }
1342 return s;
1343}
1344
1345static struct block *
1346gen_uncond(rsense)
1347 int rsense;
1348{
1349 struct block *b;
1350 struct slist *s;
1351
1352 s = new_stmt(BPF_LD|BPF_IMM);
--- 19 unchanged lines hidden (view full) ---
1372/*
1373 * Byte-swap a 32-bit number.
1374 * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
1375 * big-endian platforms.)
1376 */
1377#define SWAPLONG(y) \
1378((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
1379
1380/*
1381 * Generate code to match a particular packet type.
1382 *
1383 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
1384 * value, if <= ETHERMTU. We use that to determine whether to
1385 * match the type/length field or to check the type/length field for
1386 * a value <= ETHERMTU to see whether it's a type field and then do
1387 * the appropriate test.
1388 */
1389static struct block *
1390gen_ether_linktype(proto)
1391 register int proto;
1392{
1393 struct block *b0, *b1;
1394
1395 switch (proto) {
1396
1397 case LLCSAP_ISONS:
1398 case LLCSAP_IP:
1399 case LLCSAP_NETBEUI:
1400 /*
1401 * OSI protocols and NetBEUI always use 802.2 encapsulation,
1402 * so we check the DSAP and SSAP.
1403 *
1404 * LLCSAP_IP checks for IP-over-802.2, rather
1405 * than IP-over-Ethernet or IP-over-SNAP.
1406 *
1407 * XXX - should we check both the DSAP and the
1408 * SSAP, like this, or should we check just the
1409 * DSAP, as we do for other types <= ETHERMTU
1410 * (i.e., other SAP values)?
1411 */
1412 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1413 gen_not(b0);
1414 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H, (bpf_int32)
1415 ((proto << 8) | proto));
1416 gen_and(b0, b1);
1417 return b1;
1418
1419 case LLCSAP_IPX:
1420 /*
1421 * Check for;
1422 *
1423 * Ethernet_II frames, which are Ethernet
--- 20 unchanged lines hidden (view full) ---
1444 * XXX - should we generate the same code both
1445 * for tests for LLCSAP_IPX and for ETHERTYPE_IPX?
1446 */
1447
1448 /*
1449 * This generates code to check both for the
1450 * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3.
1451 */
1452 b0 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1453 (bpf_int32)LLCSAP_IPX);
1454 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H,
1455 (bpf_int32)0xFFFF);
1456 gen_or(b0, b1);
1457
1458 /*
1459 * Now we add code to check for SNAP frames with
1460 * ETHERTYPE_IPX, i.e. Ethernet_SNAP.
1461 */
1462 b0 = gen_snap(0x000000, ETHERTYPE_IPX, 14);
1463 gen_or(b0, b1);
1464
1465 /*
1466 * Now we generate code to check for 802.3
1467 * frames in general.
1468 */
1469 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1470 gen_not(b0);
1471
1472 /*
1473 * Now add the check for 802.3 frames before the
1474 * check for Ethernet_802.2 and Ethernet_802.3,
1475 * as those checks should only be done on 802.3
1476 * frames, not on Ethernet frames.
1477 */
1478 gen_and(b0, b1);
1479
1480 /*
1481 * Now add the check for Ethernet_II frames, and
1482 * do that before checking for the other frame
1483 * types.
1484 */
1485 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1486 (bpf_int32)ETHERTYPE_IPX);
1487 gen_or(b0, b1);
1488 return b1;
1489
1490 case ETHERTYPE_ATALK:
1491 case ETHERTYPE_AARP:
1492 /*
1493 * EtherTalk (AppleTalk protocols on Ethernet link
1494 * layer) may use 802.2 encapsulation.
1495 */
1496
1497 /*
1498 * Check for 802.2 encapsulation (EtherTalk phase 2?);
1499 * we check for an Ethernet type field less than
1500 * 1500, which means it's an 802.3 length field.
1501 */
1502 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1503 gen_not(b0);
1504
1505 /*
1506 * 802.2-encapsulated ETHERTYPE_ATALK packets are
1507 * SNAP packets with an organization code of
1508 * 0x080007 (Apple, for Appletalk) and a protocol
1509 * type of ETHERTYPE_ATALK (Appletalk).
1510 *
--- 8 unchanged lines hidden (view full) ---
1519 b1 = gen_snap(0x000000, ETHERTYPE_AARP, 14);
1520 gen_and(b0, b1);
1521
1522 /*
1523 * Check for Ethernet encapsulation (Ethertalk
1524 * phase 1?); we just check for the Ethernet
1525 * protocol type.
1526 */
1527 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
1528
1529 gen_or(b0, b1);
1530 return b1;
1531
1532 default:
1533 if (proto <= ETHERMTU) {
1534 /*
1535 * This is an LLC SAP value, so the frames
1536 * that match would be 802.2 frames.
1537 * Check that the frame is an 802.2 frame
1538 * (i.e., that the length/type field is
1539 * a length field, <= ETHERMTU) and
1540 * then check the DSAP.
1541 */
1542 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1543 gen_not(b0);
1544 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1545 (bpf_int32)proto);
1546 gen_and(b0, b1);
1547 return b1;
1548 } else {
1549 /*
1550 * This is an Ethernet type, so compare
1551 * the length/type field with it (if
1552 * the frame is an 802.2 frame, the length
1553 * field will be <= ETHERMTU, and, as
1554 * "proto" is > ETHERMTU, this test
1555 * will fail and the frame won't match,
1556 * which is what we want).
1557 */
1558 return gen_cmp(OR_LINK, off_linktype, BPF_H,
1559 (bpf_int32)proto);
1560 }
1561 }
1562}
1563
1564/*
1565 * Generate code to match a particular packet type.
1566 *
1567 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
1568 * value, if <= ETHERMTU. We use that to determine whether to
1569 * match the type field or to check the type field for the special
1570 * LINUX_SLL_P_802_2 value and then do the appropriate test.
1571 */
1572static struct block *
1573gen_linux_sll_linktype(proto)
1574 register int proto;
1575{
1576 struct block *b0, *b1;
1577
1578 switch (proto) {
1579
1580 case LLCSAP_ISONS:
1581 case LLCSAP_IP:
1582 case LLCSAP_NETBEUI:
1583 /*
1584 * OSI protocols and NetBEUI always use 802.2 encapsulation,
1585 * so we check the DSAP and SSAP.
1586 *
1587 * LLCSAP_IP checks for IP-over-802.2, rather
1588 * than IP-over-Ethernet or IP-over-SNAP.
1589 *
1590 * XXX - should we check both the DSAP and the
1591 * SSAP, like this, or should we check just the
1592 * DSAP, as we do for other types <= ETHERMTU
1593 * (i.e., other SAP values)?
1594 */
1595 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
1596 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H, (bpf_int32)
1597 ((proto << 8) | proto));
1598 gen_and(b0, b1);
1599 return b1;
1600
1601 case LLCSAP_IPX:
1602 /*
1603 * Ethernet_II frames, which are Ethernet
1604 * frames with a frame type of ETHERTYPE_IPX;
1605 *
1606 * Ethernet_802.3 frames, which have a frame
1607 * type of LINUX_SLL_P_802_3;
1608 *
--- 10 unchanged lines hidden (view full) ---
1619 * ID of ETHERTYPE_IPX in the SNAP header.
1620 *
1621 * First, do the checks on LINUX_SLL_P_802_2
1622 * frames; generate the check for either
1623 * Ethernet_802.2 or Ethernet_SNAP frames, and
1624 * then put a check for LINUX_SLL_P_802_2 frames
1625 * before it.
1626 */
1627 b0 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1628 (bpf_int32)LLCSAP_IPX);
1629 b1 = gen_snap(0x000000, ETHERTYPE_IPX,
1630 off_linktype + 2);
1631 gen_or(b0, b1);
1632 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
1633 gen_and(b0, b1);
1634
1635 /*
1636 * Now check for 802.3 frames and OR that with
1637 * the previous test.
1638 */
1639 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_3);
1640 gen_or(b0, b1);
1641
1642 /*
1643 * Now add the check for Ethernet_II frames, and
1644 * do that before checking for the other frame
1645 * types.
1646 */
1647 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1648 (bpf_int32)ETHERTYPE_IPX);
1649 gen_or(b0, b1);
1650 return b1;
1651
1652 case ETHERTYPE_ATALK:
1653 case ETHERTYPE_AARP:
1654 /*
1655 * EtherTalk (AppleTalk protocols on Ethernet link
1656 * layer) may use 802.2 encapsulation.
1657 */
1658
1659 /*
1660 * Check for 802.2 encapsulation (EtherTalk phase 2?);
1661 * we check for the 802.2 protocol type in the
1662 * "Ethernet type" field.
1663 */
1664 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
1665
1666 /*
1667 * 802.2-encapsulated ETHERTYPE_ATALK packets are
1668 * SNAP packets with an organization code of
1669 * 0x080007 (Apple, for Appletalk) and a protocol
1670 * type of ETHERTYPE_ATALK (Appletalk).
1671 *
1672 * 802.2-encapsulated ETHERTYPE_AARP packets are
--- 9 unchanged lines hidden (view full) ---
1682 off_linktype + 2);
1683 gen_and(b0, b1);
1684
1685 /*
1686 * Check for Ethernet encapsulation (Ethertalk
1687 * phase 1?); we just check for the Ethernet
1688 * protocol type.
1689 */
1690 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
1691
1692 gen_or(b0, b1);
1693 return b1;
1694
1695 default:
1696 if (proto <= ETHERMTU) {
1697 /*
1698 * This is an LLC SAP value, so the frames
1699 * that match would be 802.2 frames.
1700 * Check for the 802.2 protocol type
1701 * in the "Ethernet type" field, and
1702 * then check the DSAP.
1703 */
1704 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1705 LINUX_SLL_P_802_2);
1706 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1707 (bpf_int32)proto);
1708 gen_and(b0, b1);
1709 return b1;
1710 } else {
1711 /*
1712 * This is an Ethernet type, so compare
1713 * the length/type field with it (if
1714 * the frame is an 802.2 frame, the length
1715 * field will be <= ETHERMTU, and, as
1716 * "proto" is > ETHERMTU, this test
1717 * will fail and the frame won't match,
1718 * which is what we want).
1719 */
1720 return gen_cmp(OR_LINK, off_linktype, BPF_H,
1721 (bpf_int32)proto);
1722 }
1723 }
1724}
1725
1726static void
1727insert_radiotap_load_llprefixlen(b)
1728 struct block *b;
1729{
1730 struct slist *s1, *s2;
1731
1732 /*
1733 * Prepend to the statements in this block code to load the
1734 * length of the radiotap header into the register assigned
1735 * to hold that length, if one has been assigned.
1736 */
1737 if (reg_ll_size != -1) {
1738 /*
1739 * The 2 bytes at offsets of 2 and 3 from the beginning
1740 * of the radiotap header are the length of the radiotap
1741 * header; unfortunately, it's little-endian, so we have
1742 * to load it a byte at a time and construct the value.
1743 */
1744
1745 /*
1746 * Load the high-order byte, at an offset of 3, shift it
1747 * left a byte, and put the result in the X register.
1748 */
1749 s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
1750 s1->s.k = 3;
1751 s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
1752 sappend(s1, s2);
1753 s2->s.k = 8;
1754 s2 = new_stmt(BPF_MISC|BPF_TAX);
1755 sappend(s1, s2);
1756
1757 /*
1758 * Load the next byte, at an offset of 2, and OR the
1759 * value from the X register into it.
1760 */
1761 s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
1762 sappend(s1, s2);
1763 s2->s.k = 2;
1764 s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
1765 sappend(s1, s2);
1766
1767 /*
1768 * Now allocate a register to hold that value and store
1769 * it.
1770 */
1771 s2 = new_stmt(BPF_ST);
1772 s2->s.k = reg_ll_size;
1773 sappend(s1, s2);
1774
1775 /*
1776 * Now move it into the X register.
1777 */
1778 s2 = new_stmt(BPF_MISC|BPF_TAX);
1779 sappend(s1, s2);
1780
1781 /*
1782 * Now append all the existing statements in this
1783 * block to these statements.
1784 */
1785 sappend(s1, b->stmts);
1786 b->stmts = s1;
1787 }
1788}
1789
1790
1791static void
1792insert_load_llprefixlen(b)
1793 struct block *b;
1794{
1795 switch (linktype) {
1796
1797 case DLT_IEEE802_11_RADIO:
1798 insert_radiotap_load_llprefixlen(b);
1799 }
1800}
1801
1802
1803static struct slist *
1804gen_radiotap_llprefixlen(void)
1805{
1806 struct slist *s;
1807
1808 if (reg_ll_size == -1) {
1809 /*
1810 * We haven't yet assigned a register for the length
1811 * of the radiotap header; allocate one.
1812 */
1813 reg_ll_size = alloc_reg();
1814 }
1815
1816 /*
1817 * Load the register containing the radiotap length
1818 * into the X register.
1819 */
1820 s = new_stmt(BPF_LDX|BPF_MEM);
1821 s->s.k = reg_ll_size;
1822 return s;
1823}
1824
1825/*
1826 * Generate code to compute the link-layer header length, if necessary,
1827 * putting it into the X register, and to return either a pointer to a
1828 * "struct slist" for the list of statements in that code, or NULL if
1829 * no code is necessary.
1830 */
1831static struct slist *
1832gen_llprefixlen(void)
1833{
1834 switch (linktype) {
1835
1836 case DLT_IEEE802_11_RADIO:
1837 return gen_radiotap_llprefixlen();
1838
1839 default:
1840 return NULL;
1841 }
1842}
1843
1844/*
1845 * Generate code to match a particular packet type by matching the
1846 * link-layer type field or fields in the 802.2 LLC header.
1847 *
1848 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
1849 * value, if <= ETHERMTU.
1850 */
1851static struct block *
1852gen_linktype(proto)
1853 register int proto;
1854{
1855 struct block *b0, *b1, *b2;
1856
1857 switch (linktype) {
1858
--- 5 unchanged lines hidden (view full) ---
1864 case DLT_C_HDLC:
1865 switch (proto) {
1866
1867 case LLCSAP_ISONS:
1868 proto = (proto << 8 | LLCSAP_ISONS);
1869 /* fall through */
1870
1871 default:
1872 return gen_cmp(OR_LINK, off_linktype, BPF_H,
1873 (bpf_int32)proto);
1874 /*NOTREACHED*/
1875 break;
1876 }
1877 break;
1878
1879 case DLT_FDDI:
1880 case DLT_IEEE802:
1881 case DLT_IEEE802_11:
1882 case DLT_IEEE802_11_RADIO_AVS:
1883 case DLT_IEEE802_11_RADIO:
1884 case DLT_PRISM_HEADER:
1885 case DLT_ATM_RFC1483:
1886 case DLT_ATM_CLIP:
1887 case DLT_IP_OVER_FC:
1888 return gen_llc_linktype(proto);
1889 /*NOTREACHED*/
1890 break;
1891
1892 case DLT_SUNATM:
1893 /*
1894 * If "is_lane" is set, check for a LANE-encapsulated
1895 * version of this protocol, otherwise check for an
1896 * LLC-encapsulated version of this protocol.
1897 *
1898 * We assume LANE means Ethernet, not Token Ring.
1899 */
1900 if (is_lane) {
1901 /*
1902 * Check that the packet doesn't begin with an
1903 * LE Control marker. (We've already generated
1904 * a test for LANE.)
1905 */
1906 b0 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
1907 0xFF00);
1908 gen_not(b0);
1909
1910 /*
1911 * Now generate an Ethernet test.
1912 */
1913 b1 = gen_ether_linktype(proto);
1914 gen_and(b0, b1);
1915 return b1;
1916 } else {
1917 /*
1918 * Check for LLC encapsulation and then check the
1919 * protocol.
1920 */
1921 b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
1922 b1 = gen_llc_linktype(proto);
1923 gen_and(b0, b1);
1924 return b1;
1925 }
1926 /*NOTREACHED*/
1927 break;
1928
1929 case DLT_LINUX_SLL:
1930 return gen_linux_sll_linktype(proto);
1931 /*NOTREACHED*/
1932 break;
1933
1934 case DLT_SLIP:
1935 case DLT_SLIP_BSDOS:
--- 73 unchanged lines hidden (view full) ---
2009 case DLT_PPP_BSDOS:
2010 /*
2011 * We use Ethernet protocol types inside libpcap;
2012 * map them to the corresponding PPP protocol types.
2013 */
2014 switch (proto) {
2015
2016 case ETHERTYPE_IP:
2017 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_IP);
2018 b1 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJC);
2019 gen_or(b0, b1);
2020 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJNC);
2021 gen_or(b1, b0);
2022 return b0;
2023
2024#ifdef INET6
2025 case ETHERTYPE_IPV6:
2026 proto = PPP_IPV6;
2027 /* more to go? */
2028 break;
--- 89 unchanged lines hidden (view full) ---
2118 * Then we run it through "htonl()", and
2119 * generate code to compare against the result.
2120 */
2121 if (bpf_pcap->sf.rfile != NULL &&
2122 bpf_pcap->sf.swapped)
2123 proto = SWAPLONG(proto);
2124 proto = htonl(proto);
2125 }
2126 return (gen_cmp(OR_LINK, 0, BPF_W, (bpf_int32)proto));
2127
2128 case DLT_PFLOG:
2129 /*
2130 * af field is host byte order in contrast to the rest of
2131 * the packet.
2132 */
2133 if (proto == ETHERTYPE_IP)
2134 return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
2135 BPF_B, (bpf_int32)AF_INET));
2136#ifdef INET6
2137 else if (proto == ETHERTYPE_IPV6)
2138 return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
2139 BPF_B, (bpf_int32)AF_INET6));
2140#endif /* INET6 */
2141 else
2142 return gen_false();
2143 /*NOTREACHED*/
2144 break;
2145
2146 case DLT_ARCNET:
2147 case DLT_ARCNET_LINUX:
2148 /*
2149 * XXX should we check for first fragment if the protocol
2150 * uses PHDS?
2151 */
2152 switch (proto) {
2153
2154 default:
2155 return gen_false();
2156
2157#ifdef INET6
2158 case ETHERTYPE_IPV6:
2159 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
2160 (bpf_int32)ARCTYPE_INET6));
2161#endif /* INET6 */
2162
2163 case ETHERTYPE_IP:
2164 b0 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2165 (bpf_int32)ARCTYPE_IP);
2166 b1 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2167 (bpf_int32)ARCTYPE_IP_OLD);
2168 gen_or(b0, b1);
2169 return (b1);
2170
2171 case ETHERTYPE_ARP:
2172 b0 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2173 (bpf_int32)ARCTYPE_ARP);
2174 b1 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2175 (bpf_int32)ARCTYPE_ARP_OLD);
2176 gen_or(b0, b1);
2177 return (b1);
2178
2179 case ETHERTYPE_REVARP:
2180 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
2181 (bpf_int32)ARCTYPE_REVARP));
2182
2183 case ETHERTYPE_ATALK:
2184 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
2185 (bpf_int32)ARCTYPE_ATALK));
2186 }
2187 /*NOTREACHED*/
2188 break;
2189
2190 case DLT_LTALK:
2191 switch (proto) {
2192 case ETHERTYPE_ATALK:
--- 10 unchanged lines hidden (view full) ---
2203 * DLCI and flags. What if the address is longer?
2204 */
2205 switch (proto) {
2206
2207 case ETHERTYPE_IP:
2208 /*
2209 * Check for the special NLPID for IP.
2210 */
2211 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0xcc);
2212
2213#ifdef INET6
2214 case ETHERTYPE_IPV6:
2215 /*
2216 * Check for the special NLPID for IPv6.
2217 */
2218 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0x8e);
2219#endif
2220
2221 case LLCSAP_ISONS:
2222 /*
2223 * Check for several OSI protocols.
2224 *
2225 * Frame Relay packets typically have an OSI
2226 * NLPID at the beginning; we check for each
2227 * of them.
2228 *
2229 * What we check for is the NLPID and a frame
2230 * control field of UI, i.e. 0x03 followed
2231 * by the NLPID.
2232 */
2233 b0 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO8473_CLNP);
2234 b1 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO9542_ESIS);
2235 b2 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO10589_ISIS);
2236 gen_or(b1, b2);
2237 gen_or(b0, b2);
2238 return b2;
2239
2240 default:
2241 return gen_false();
2242 }
2243 /*NOTREACHED*/
2244 break;
2245
2246 case DLT_JUNIPER_MLFR:
2247 case DLT_JUNIPER_MLPPP:
2248 case DLT_JUNIPER_ATM1:
2249 case DLT_JUNIPER_ATM2:
2250 case DLT_JUNIPER_PPPOE:
2251 case DLT_JUNIPER_PPPOE_ATM:
2252 case DLT_JUNIPER_GGSN:
2253 case DLT_JUNIPER_ES:
2254 case DLT_JUNIPER_MONITOR:
2255 case DLT_JUNIPER_SERVICES:
2256 /* just lets verify the magic number for now -
2257 * on ATM we may have up to 6 different encapsulations on the wire
2258 * and need a lot of heuristics to figure out that the payload
2259 * might be;
2260 *
2261 * FIXME encapsulation specific BPF_ filters
2262 */
2263 return gen_mcmp(OR_LINK, 0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */
2264
2265 case DLT_LINUX_IRDA:
2266 bpf_error("IrDA link-layer type filtering not implemented");
2267
2268 case DLT_DOCSIS:
2269 bpf_error("DOCSIS link-layer type filtering not implemented");
2270
2271 case DLT_LINUX_LAPD:
2272 bpf_error("LAPD link-layer type filtering not implemented");
2273 }
2274
2275 /*
2276 * All the types that have no encapsulation should either be
2277 * handled as DLT_SLIP, DLT_SLIP_BSDOS, and DLT_RAW are, if
2278 * all packets are IP packets, or should be handled in some
2279 * special case, if none of them are (if some are and some
2280 * aren't, the lack of encapsulation is a problem, as we'd
--- 8 unchanged lines hidden (view full) ---
2289 * Any type not handled above should always have an Ethernet
2290 * type at an offset of "off_linktype". (PPP is partially
2291 * handled above - the protocol type is mapped from the
2292 * Ethernet and LLC types we use internally to the corresponding
2293 * PPP type - but the PPP type is always specified by a value
2294 * at "off_linktype", so we don't have to do the code generation
2295 * above.)
2296 */
2297 return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
2298}
2299
2300/*
2301 * Check for an LLC SNAP packet with a given organization code and
2302 * protocol type; we check the entire contents of the 802.2 LLC and
2303 * snap headers, checking for DSAP and SSAP of SNAP and a control
2304 * field of 0x03 in the LLC header, and for the specified organization
2305 * code and protocol type in the SNAP header.
--- 9 unchanged lines hidden (view full) ---
2315 snapblock[0] = LLCSAP_SNAP; /* DSAP = SNAP */
2316 snapblock[1] = LLCSAP_SNAP; /* SSAP = SNAP */
2317 snapblock[2] = 0x03; /* control = UI */
2318 snapblock[3] = (orgcode >> 16); /* upper 8 bits of organization code */
2319 snapblock[4] = (orgcode >> 8); /* middle 8 bits of organization code */
2320 snapblock[5] = (orgcode >> 0); /* lower 8 bits of organization code */
2321 snapblock[6] = (ptype >> 8); /* upper 8 bits of protocol type */
2322 snapblock[7] = (ptype >> 0); /* lower 8 bits of protocol type */
2323 return gen_bcmp(OR_LINK, offset, 8, snapblock);
2324}
2325
2326/*
2327 * Generate code to match a particular packet type, for link-layer types
2328 * using 802.2 LLC headers.
2329 *
2330 * This is *NOT* used for Ethernet; "gen_ether_linktype()" is used
2331 * for that - it handles the D/I/X Ethernet vs. 802.3+802.2 issues.
2332 *
2333 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
2334 * value, if <= ETHERMTU. We use that to determine whether to
2335 * match the DSAP or both DSAP and LSAP or to check the OUI and
2336 * protocol ID in a SNAP header.
2337 */
2338static struct block *
2339gen_llc_linktype(proto)
2340 int proto;
2341{
2342 /*
2343 * XXX - handle token-ring variable-length header.
2344 */
2345 switch (proto) {
2346
2347 case LLCSAP_IP:
2348 case LLCSAP_ISONS:
2349 case LLCSAP_NETBEUI:
2350 /*
2351 * XXX - should we check both the DSAP and the
2352 * SSAP, like this, or should we check just the
2353 * DSAP, as we do for other types <= ETHERMTU
2354 * (i.e., other SAP values)?
2355 */
2356 return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_u_int32)
2357 ((proto << 8) | proto));
2358
2359 case LLCSAP_IPX:
2360 /*
2361 * XXX - are there ever SNAP frames for IPX on
2362 * non-Ethernet 802.x networks?
2363 */
2364 return gen_cmp(OR_LINK, off_linktype, BPF_B,
2365 (bpf_int32)LLCSAP_IPX);
2366
2367 case ETHERTYPE_ATALK:
2368 /*
2369 * 802.2-encapsulated ETHERTYPE_ATALK packets are
2370 * SNAP packets with an organization code of
2371 * 0x080007 (Apple, for Appletalk) and a protocol
2372 * type of ETHERTYPE_ATALK (Appletalk).
2373 *
--- 7 unchanged lines hidden (view full) ---
2381 * XXX - we don't have to check for IPX 802.3
2382 * here, but should we check for the IPX Ethertype?
2383 */
2384 if (proto <= ETHERMTU) {
2385 /*
2386 * This is an LLC SAP value, so check
2387 * the DSAP.
2388 */
2389 return gen_cmp(OR_LINK, off_linktype, BPF_B,
2390 (bpf_int32)proto);
2391 } else {
2392 /*
2393 * This is an Ethernet type; we assume that it's
2394 * unlikely that it'll appear in the right place
2395 * at random, and therefore check only the
2396 * location that would hold the Ethernet type
2397 * in a SNAP frame with an organization code of
2398 * 0x000000 (encapsulated Ethernet).
--- 5 unchanged lines hidden (view full) ---
2404 *
2405 * return gen_snap(0x000000, proto,
2406 * off_linktype);
2407 *
2408 * here; for now, we don't, as per the above.
2409 * I don't know whether it's worth the extra CPU
2410 * time to do the right check or not.
2411 */
2412 return gen_cmp(OR_LINK, off_linktype+6, BPF_H,
2413 (bpf_int32)proto);
2414 }
2415 }
2416}
2417
2418static struct block *
2419gen_hostop(addr, mask, dir, proto, src_off, dst_off)
2420 bpf_u_int32 addr;
2421 bpf_u_int32 mask;
--- 25 unchanged lines hidden (view full) ---
2447 b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
2448 gen_or(b0, b1);
2449 return b1;
2450
2451 default:
2452 abort();
2453 }
2454 b0 = gen_linktype(proto);
2455 b1 = gen_mcmp(OR_NET, offset, BPF_W, (bpf_int32)addr, mask);
2456 gen_and(b0, b1);
2457 return b1;
2458}
2459
2460#ifdef INET6
2461static struct block *
2462gen_hostop6(addr, mask, dir, proto, src_off, dst_off)
2463 struct in6_addr *addr;
--- 29 unchanged lines hidden (view full) ---
2493 return b1;
2494
2495 default:
2496 abort();
2497 }
2498 /* this order is important */
2499 a = (u_int32_t *)addr;
2500 m = (u_int32_t *)mask;
2501 b1 = gen_mcmp(OR_NET, offset + 12, BPF_W, ntohl(a[3]), ntohl(m[3]));
2502 b0 = gen_mcmp(OR_NET, offset + 8, BPF_W, ntohl(a[2]), ntohl(m[2]));
2503 gen_and(b0, b1);
2504 b0 = gen_mcmp(OR_NET, offset + 4, BPF_W, ntohl(a[1]), ntohl(m[1]));
2505 gen_and(b0, b1);
2506 b0 = gen_mcmp(OR_NET, offset + 0, BPF_W, ntohl(a[0]), ntohl(m[0]));
2507 gen_and(b0, b1);
2508 b0 = gen_linktype(proto);
2509 gen_and(b0, b1);
2510 return b1;
2511}
2512#endif /*INET6*/
2513
2514static struct block *
2515gen_ehostop(eaddr, dir)
2516 register const u_char *eaddr;
2517 register int dir;
2518{
2519 register struct block *b0, *b1;
2520
2521 switch (dir) {
2522 case Q_SRC:
2523 return gen_bcmp(OR_LINK, off_mac + 6, 6, eaddr);
2524
2525 case Q_DST:
2526 return gen_bcmp(OR_LINK, off_mac + 0, 6, eaddr);
2527
2528 case Q_AND:
2529 b0 = gen_ehostop(eaddr, Q_SRC);
2530 b1 = gen_ehostop(eaddr, Q_DST);
2531 gen_and(b0, b1);
2532 return b1;
2533
2534 case Q_DEFAULT:
--- 15 unchanged lines hidden (view full) ---
2550 register const u_char *eaddr;
2551 register int dir;
2552{
2553 struct block *b0, *b1;
2554
2555 switch (dir) {
2556 case Q_SRC:
2557#ifdef PCAP_FDDIPAD
2558 return gen_bcmp(OR_LINK, 6 + 1 + pcap_fddipad, 6, eaddr);
2559#else
2560 return gen_bcmp(OR_LINK, 6 + 1, 6, eaddr);
2561#endif
2562
2563 case Q_DST:
2564#ifdef PCAP_FDDIPAD
2565 return gen_bcmp(OR_LINK, 0 + 1 + pcap_fddipad, 6, eaddr);
2566#else
2567 return gen_bcmp(OR_LINK, 0 + 1, 6, eaddr);
2568#endif
2569
2570 case Q_AND:
2571 b0 = gen_fhostop(eaddr, Q_SRC);
2572 b1 = gen_fhostop(eaddr, Q_DST);
2573 gen_and(b0, b1);
2574 return b1;
2575
--- 15 unchanged lines hidden (view full) ---
2591gen_thostop(eaddr, dir)
2592 register const u_char *eaddr;
2593 register int dir;
2594{
2595 register struct block *b0, *b1;
2596
2597 switch (dir) {
2598 case Q_SRC:
2599 return gen_bcmp(OR_LINK, 8, 6, eaddr);
2600
2601 case Q_DST:
2602 return gen_bcmp(OR_LINK, 2, 6, eaddr);
2603
2604 case Q_AND:
2605 b0 = gen_thostop(eaddr, Q_SRC);
2606 b1 = gen_thostop(eaddr, Q_DST);
2607 gen_and(b0, b1);
2608 return b1;
2609
2610 case Q_DEFAULT:
--- 40 unchanged lines hidden (view full) ---
2651 */
2652
2653 /*
2654 * Generate the tests to be done for data frames
2655 * with From DS set.
2656 *
2657 * First, check for To DS set, i.e. check "link[1] & 0x01".
2658 */
2659 s = gen_load_a(OR_LINK, 1, BPF_B);
2660 b1 = new_block(JMP(BPF_JSET));
2661 b1->s.k = 0x01; /* To DS */
2662 b1->stmts = s;
2663
2664 /*
2665 * If To DS is set, the SA is at 24.
2666 */
2667 b0 = gen_bcmp(OR_LINK, 24, 6, eaddr);
2668 gen_and(b1, b0);
2669
2670 /*
2671 * Now, check for To DS not set, i.e. check
2672 * "!(link[1] & 0x01)".
2673 */
2674 s = gen_load_a(OR_LINK, 1, BPF_B);
2675 b2 = new_block(JMP(BPF_JSET));
2676 b2->s.k = 0x01; /* To DS */
2677 b2->stmts = s;
2678 gen_not(b2);
2679
2680 /*
2681 * If To DS is not set, the SA is at 16.
2682 */
2683 b1 = gen_bcmp(OR_LINK, 16, 6, eaddr);
2684 gen_and(b2, b1);
2685
2686 /*
2687 * Now OR together the last two checks. That gives
2688 * the complete set of checks for data frames with
2689 * From DS set.
2690 */
2691 gen_or(b1, b0);
2692
2693 /*
2694 * Now check for From DS being set, and AND that with
2695 * the ORed-together checks.
2696 */
2697 s = gen_load_a(OR_LINK, 1, BPF_B);
2698 b1 = new_block(JMP(BPF_JSET));
2699 b1->s.k = 0x02; /* From DS */
2700 b1->stmts = s;
2701 gen_and(b1, b0);
2702
2703 /*
2704 * Now check for data frames with From DS not set.
2705 */
2706 s = gen_load_a(OR_LINK, 1, BPF_B);
2707 b2 = new_block(JMP(BPF_JSET));
2708 b2->s.k = 0x02; /* From DS */
2709 b2->stmts = s;
2710 gen_not(b2);
2711
2712 /*
2713 * If From DS isn't set, the SA is at 10.
2714 */
2715 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
2716 gen_and(b2, b1);
2717
2718 /*
2719 * Now OR together the checks for data frames with
2720 * From DS not set and for data frames with From DS
2721 * set; that gives the checks done for data frames.
2722 */
2723 gen_or(b1, b0);
2724
2725 /*
2726 * Now check for a data frame.
2727 * I.e, check "link[0] & 0x08".
2728 */
2729 gen_load_a(OR_LINK, 0, BPF_B);
2730 b1 = new_block(JMP(BPF_JSET));
2731 b1->s.k = 0x08;
2732 b1->stmts = s;
2733
2734 /*
2735 * AND that with the checks done for data frames.
2736 */
2737 gen_and(b1, b0);
2738
2739 /*
2740 * If the high-order bit of the type value is 0, this
2741 * is a management frame.
2742 * I.e, check "!(link[0] & 0x08)".
2743 */
2744 s = gen_load_a(OR_LINK, 0, BPF_B);
2745 b2 = new_block(JMP(BPF_JSET));
2746 b2->s.k = 0x08;
2747 b2->stmts = s;
2748 gen_not(b2);
2749
2750 /*
2751 * For management frames, the SA is at 10.
2752 */
2753 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
2754 gen_and(b2, b1);
2755
2756 /*
2757 * OR that with the checks done for data frames.
2758 * That gives the checks done for management and
2759 * data frames.
2760 */
2761 gen_or(b1, b0);
2762
2763 /*
2764 * If the low-order bit of the type value is 1,
2765 * this is either a control frame or a frame
2766 * with a reserved type, and thus not a
2767 * frame with an SA.
2768 *
2769 * I.e., check "!(link[0] & 0x04)".
2770 */
2771 s = gen_load_a(OR_LINK, 0, BPF_B);
2772 b1 = new_block(JMP(BPF_JSET));
2773 b1->s.k = 0x04;
2774 b1->stmts = s;
2775 gen_not(b1);
2776
2777 /*
2778 * AND that with the checks for data and management
2779 * frames.
--- 18 unchanged lines hidden (view full) ---
2798 * if To DS is set.
2799 */
2800
2801 /*
2802 * Generate the tests to be done for data frames.
2803 *
2804 * First, check for To DS set, i.e. "link[1] & 0x01".
2805 */
2806 s = gen_load_a(OR_LINK, 1, BPF_B);
2807 b1 = new_block(JMP(BPF_JSET));
2808 b1->s.k = 0x01; /* To DS */
2809 b1->stmts = s;
2810
2811 /*
2812 * If To DS is set, the DA is at 16.
2813 */
2814 b0 = gen_bcmp(OR_LINK, 16, 6, eaddr);
2815 gen_and(b1, b0);
2816
2817 /*
2818 * Now, check for To DS not set, i.e. check
2819 * "!(link[1] & 0x01)".
2820 */
2821 s = gen_load_a(OR_LINK, 1, BPF_B);
2822 b2 = new_block(JMP(BPF_JSET));
2823 b2->s.k = 0x01; /* To DS */
2824 b2->stmts = s;
2825 gen_not(b2);
2826
2827 /*
2828 * If To DS is not set, the DA is at 4.
2829 */
2830 b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
2831 gen_and(b2, b1);
2832
2833 /*
2834 * Now OR together the last two checks. That gives
2835 * the complete set of checks for data frames.
2836 */
2837 gen_or(b1, b0);
2838
2839 /*
2840 * Now check for a data frame.
2841 * I.e, check "link[0] & 0x08".
2842 */
2843 s = gen_load_a(OR_LINK, 0, BPF_B);
2844 b1 = new_block(JMP(BPF_JSET));
2845 b1->s.k = 0x08;
2846 b1->stmts = s;
2847
2848 /*
2849 * AND that with the checks done for data frames.
2850 */
2851 gen_and(b1, b0);
2852
2853 /*
2854 * If the high-order bit of the type value is 0, this
2855 * is a management frame.
2856 * I.e, check "!(link[0] & 0x08)".
2857 */
2858 s = gen_load_a(OR_LINK, 0, BPF_B);
2859 b2 = new_block(JMP(BPF_JSET));
2860 b2->s.k = 0x08;
2861 b2->stmts = s;
2862 gen_not(b2);
2863
2864 /*
2865 * For management frames, the DA is at 4.
2866 */
2867 b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
2868 gen_and(b2, b1);
2869
2870 /*
2871 * OR that with the checks done for data frames.
2872 * That gives the checks done for management and
2873 * data frames.
2874 */
2875 gen_or(b1, b0);
2876
2877 /*
2878 * If the low-order bit of the type value is 1,
2879 * this is either a control frame or a frame
2880 * with a reserved type, and thus not a
2881 * frame with an SA.
2882 *
2883 * I.e., check "!(link[0] & 0x04)".
2884 */
2885 s = gen_load_a(OR_LINK, 0, BPF_B);
2886 b1 = new_block(JMP(BPF_JSET));
2887 b1->s.k = 0x04;
2888 b1->stmts = s;
2889 gen_not(b1);
2890
2891 /*
2892 * AND that with the checks for data and management
2893 * frames.
--- 27 unchanged lines hidden (view full) ---
2921gen_ipfchostop(eaddr, dir)
2922 register const u_char *eaddr;
2923 register int dir;
2924{
2925 register struct block *b0, *b1;
2926
2927 switch (dir) {
2928 case Q_SRC:
2929 return gen_bcmp(OR_LINK, 10, 6, eaddr);
2930
2931 case Q_DST:
2932 return gen_bcmp(OR_LINK, 2, 6, eaddr);
2933
2934 case Q_AND:
2935 b0 = gen_ipfchostop(eaddr, Q_SRC);
2936 b1 = gen_ipfchostop(eaddr, Q_DST);
2937 gen_and(b0, b1);
2938 return b1;
2939
2940 case Q_DEFAULT:
--- 21 unchanged lines hidden (view full) ---
2962 * will require a lot more hacking.
2963 *
2964 * To add support for filtering on DECNET "areas" (network numbers)
2965 * one would want to add a "mask" argument to this routine. That would
2966 * make the filter even more inefficient, although one could be clever
2967 * and not generate masking instructions if the mask is 0xFFFF.
2968 */
2969static struct block *
2970gen_dnhostop(addr, dir)
2971 bpf_u_int32 addr;
2972 int dir;
2973{
2974 struct block *b0, *b1, *b2, *tmp;
2975 u_int offset_lh; /* offset if long header is received */
2976 u_int offset_sh; /* offset if short header is received */
2977
2978 switch (dir) {
2979
2980 case Q_DST:
2981 offset_sh = 1; /* follows flags */
2982 offset_lh = 7; /* flgs,darea,dsubarea,HIORD */
2983 break;
2984
2985 case Q_SRC:
2986 offset_sh = 3; /* follows flags, dstnode */
2987 offset_lh = 15; /* flgs,darea,dsubarea,did,sarea,ssub,HIORD */
2988 break;
2989
2990 case Q_AND:
2991 /* Inefficient because we do our Calvinball dance twice */
2992 b0 = gen_dnhostop(addr, Q_SRC);
2993 b1 = gen_dnhostop(addr, Q_DST);
2994 gen_and(b0, b1);
2995 return b1;
2996
2997 case Q_OR:
2998 case Q_DEFAULT:
2999 /* Inefficient because we do our Calvinball dance twice */
3000 b0 = gen_dnhostop(addr, Q_SRC);
3001 b1 = gen_dnhostop(addr, Q_DST);
3002 gen_or(b0, b1);
3003 return b1;
3004
3005 case Q_ISO:
3006 bpf_error("ISO host filtering not implemented");
3007
3008 default:
3009 abort();
3010 }
3011 b0 = gen_linktype(ETHERTYPE_DN);
3012 /* Check for pad = 1, long header case */
3013 tmp = gen_mcmp(OR_NET, 2, BPF_H,
3014 (bpf_int32)ntohs(0x0681), (bpf_int32)ntohs(0x07FF));
3015 b1 = gen_cmp(OR_NET, 2 + 1 + offset_lh,
3016 BPF_H, (bpf_int32)ntohs(addr));
3017 gen_and(tmp, b1);
3018 /* Check for pad = 0, long header case */
3019 tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x06, (bpf_int32)0x7);
3020 b2 = gen_cmp(OR_NET, 2 + offset_lh, BPF_H, (bpf_int32)ntohs(addr));
3021 gen_and(tmp, b2);
3022 gen_or(b2, b1);
3023 /* Check for pad = 1, short header case */
3024 tmp = gen_mcmp(OR_NET, 2, BPF_H,
3025 (bpf_int32)ntohs(0x0281), (bpf_int32)ntohs(0x07FF));
3026 b2 = gen_cmp(OR_NET, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs(addr));
3027 gen_and(tmp, b2);
3028 gen_or(b2, b1);
3029 /* Check for pad = 0, short header case */
3030 tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x02, (bpf_int32)0x7);
3031 b2 = gen_cmp(OR_NET, 2 + offset_sh, BPF_H, (bpf_int32)ntohs(addr));
3032 gen_and(tmp, b2);
3033 gen_or(b2, b1);
3034
3035 /* Combine with test for linktype */
3036 gen_and(b0, b1);
3037 return b1;
3038}
3039
--- 14 unchanged lines hidden (view full) ---
3054 b1 = gen_host(addr, mask, Q_ARP, dir);
3055 gen_or(b0, b1);
3056 b0 = gen_host(addr, mask, Q_RARP, dir);
3057 gen_or(b1, b0);
3058 }
3059 return b0;
3060
3061 case Q_IP:
3062 return gen_hostop(addr, mask, dir, ETHERTYPE_IP, 12, 16);
3063
3064 case Q_RARP:
3065 return gen_hostop(addr, mask, dir, ETHERTYPE_REVARP, 14, 24);
3066
3067 case Q_ARP:
3068 return gen_hostop(addr, mask, dir, ETHERTYPE_ARP, 14, 24);
3069
3070 case Q_TCP:
3071 bpf_error("'tcp' modifier applied to host");
3072
3073 case Q_SCTP:
3074 bpf_error("'sctp' modifier applied to host");
3075
3076 case Q_UDP:
--- 16 unchanged lines hidden (view full) ---
3093
3094 case Q_ATALK:
3095 bpf_error("ATALK host filtering not implemented");
3096
3097 case Q_AARP:
3098 bpf_error("AARP host filtering not implemented");
3099
3100 case Q_DECNET:
3101 return gen_dnhostop(addr, dir);
3102
3103 case Q_SCA:
3104 bpf_error("SCA host filtering not implemented");
3105
3106 case Q_LAT:
3107 bpf_error("LAT host filtering not implemented");
3108
3109 case Q_MOPDL:
--- 32 unchanged lines hidden (view full) ---
3142 bpf_error("'stp' modifier applied to host");
3143
3144 case Q_IPX:
3145 bpf_error("IPX host filtering not implemented");
3146
3147 case Q_NETBEUI:
3148 bpf_error("'netbeui' modifier applied to host");
3149
3150 case Q_RADIO:
3151 bpf_error("'radio' modifier applied to host");
3152
3153 default:
3154 abort();
3155 }
3156 /* NOTREACHED */
3157}
3158
3159#ifdef INET6
3160static struct block *
--- 58 unchanged lines hidden (view full) ---
3219
3220 case Q_MOPDL:
3221 bpf_error("MOPDL host filtering not implemented");
3222
3223 case Q_MOPRC:
3224 bpf_error("MOPRC host filtering not implemented");
3225
3226 case Q_IPV6:
3227 return gen_hostop6(addr, mask, dir, ETHERTYPE_IPV6, 8, 24);
3228
3229 case Q_ICMPV6:
3230 bpf_error("'icmp6' modifier applied to host");
3231
3232 case Q_AH:
3233 bpf_error("'ah' modifier applied to host");
3234
3235 case Q_ESP:
--- 15 unchanged lines hidden (view full) ---
3251 bpf_error("'stp' modifier applied to host");
3252
3253 case Q_IPX:
3254 bpf_error("IPX host filtering not implemented");
3255
3256 case Q_NETBEUI:
3257 bpf_error("'netbeui' modifier applied to host");
3258
3259 case Q_RADIO:
3260 bpf_error("'radio' modifier applied to host");
3261
3262 default:
3263 abort();
3264 }
3265 /* NOTREACHED */
3266}
3267#endif /*INET6*/
3268
3269#ifndef INET6
--- 15 unchanged lines hidden (view full) ---
3285 case Q_ARP:
3286 case Q_RARP:
3287 if (linktype == DLT_EN10MB)
3288 b0 = gen_ehostop(eaddr, Q_OR);
3289 else if (linktype == DLT_FDDI)
3290 b0 = gen_fhostop(eaddr, Q_OR);
3291 else if (linktype == DLT_IEEE802)
3292 b0 = gen_thostop(eaddr, Q_OR);
3293 else if (linktype == DLT_IEEE802_11 ||
3294 linktype == DLT_IEEE802_11_RADIO_AVS ||
3295 linktype == DLT_IEEE802_11_RADIO ||
3296 linktype == DLT_PRISM_HEADER)
3297 b0 = gen_wlanhostop(eaddr, Q_OR);
3298 else if (linktype == DLT_SUNATM && is_lane) {
3299 /*
3300 * Check that the packet doesn't begin with an
3301 * LE Control marker. (We've already generated
3302 * a test for LANE.)
3303 */
3304 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
3305 0xFF00);
3306 gen_not(b1);
3307
3308 /*
3309 * Now check the MAC address.
3310 */
3311 b0 = gen_ehostop(eaddr, Q_OR);
3312 gen_and(b1, b0);
3313 } else if (linktype == DLT_IP_OVER_FC)
--- 250 unchanged lines hidden (view full) ---
3564 case Q_IPX:
3565 b1 = gen_linktype(LLCSAP_IPX);
3566 break;
3567
3568 case Q_NETBEUI:
3569 b1 = gen_linktype(LLCSAP_NETBEUI);
3570 break;
3571
3572 case Q_RADIO:
3573 bpf_error("'radio' is not a valid protocol type");
3574
3575 default:
3576 abort();
3577 }
3578 return b1;
3579}
3580
3581static struct block *
3582gen_ipfrag()
3583{
3584 struct slist *s;
3585 struct block *b;
3586
3587 /* not ip frag */
3588 s = gen_load_a(OR_NET, 6, BPF_H);
3589 b = new_block(JMP(BPF_JSET));
3590 b->s.k = 0x1fff;
3591 b->stmts = s;
3592 gen_not(b);
3593
3594 return b;
3595}
3596
3597/*
3598 * Generate a comparison to a port value in the transport-layer header
3599 * at the specified offset from the beginning of that header.
3600 *
3601 * XXX - this handles a variable-length prefix preceding the link-layer
3602 * header, such as the radiotap or AVS radio prefix, but doesn't handle
3603 * variable-length link-layer headers (such as Token Ring or 802.11
3604 * headers).
3605 */
3606static struct block *
3607gen_portatom(off, v)
3608 int off;
3609 bpf_int32 v;
3610{
3611 return gen_cmp(OR_TRAN_IPV4, off, BPF_H, v);
3612}
3613
3614#ifdef INET6
3615static struct block *
3616gen_portatom6(off, v)
3617 int off;
3618 bpf_int32 v;
3619{
3620 return gen_cmp(OR_TRAN_IPV6, off, BPF_H, v);
3621}
3622#endif/*INET6*/
3623
3624struct block *
3625gen_portop(port, proto, dir)
3626 int port, proto, dir;
3627{
3628 struct block *b0, *b1, *tmp;
3629
3630 /* ip proto 'proto' */
3631 tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto);
3632 b0 = gen_ipfrag();
3633 gen_and(tmp, b0);
3634
3635 switch (dir) {
3636 case Q_SRC:
3637 b1 = gen_portatom(0, (bpf_int32)port);
3638 break;
3639
--- 73 unchanged lines hidden (view full) ---
3713
3714#ifdef INET6
3715struct block *
3716gen_portop6(port, proto, dir)
3717 int port, proto, dir;
3718{
3719 struct block *b0, *b1, *tmp;
3720
3721 /* ip6 proto 'proto' */
3722 b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto);
3723
3724 switch (dir) {
3725 case Q_SRC:
3726 b1 = gen_portatom6(0, (bpf_int32)port);
3727 break;
3728
3729 case Q_DST:
3730 b1 = gen_portatom6(2, (bpf_int32)port);
--- 23 unchanged lines hidden (view full) ---
3754static struct block *
3755gen_port6(port, ip_proto, dir)
3756 int port;
3757 int ip_proto;
3758 int dir;
3759{
3760 struct block *b0, *b1, *tmp;
3761
3762 /* link proto ip6 */
3763 b0 = gen_linktype(ETHERTYPE_IPV6);
3764
3765 switch (ip_proto) {
3766 case IPPROTO_UDP:
3767 case IPPROTO_TCP:
3768 case IPPROTO_SCTP:
3769 b1 = gen_portop6(port, ip_proto, dir);
3770 break;
--- 9 unchanged lines hidden (view full) ---
3780 default:
3781 abort();
3782 }
3783 gen_and(b0, b1);
3784 return b1;
3785}
3786#endif /* INET6 */
3787
3788/* gen_portrange code */
3789static struct block *
3790gen_portrangeatom(off, v1, v2)
3791 int off;
3792 bpf_int32 v1, v2;
3793{
3794 struct block *b1, *b2;
3795
3796 if (v1 > v2) {
3797 /*
3798 * Reverse the order of the ports, so v1 is the lower one.
3799 */
3800 bpf_int32 vtemp;
3801
3802 vtemp = v1;
3803 v1 = v2;
3804 v2 = vtemp;
3805 }
3806
3807 b1 = gen_cmp_ge(OR_TRAN_IPV4, off, BPF_H, v1);
3808 b2 = gen_cmp_le(OR_TRAN_IPV4, off, BPF_H, v2);
3809
3810 gen_and(b1, b2);
3811
3812 return b2;
3813}
3814
3815struct block *
3816gen_portrangeop(port1, port2, proto, dir)
3817 int port1, port2;
3818 int proto;
3819 int dir;
3820{
3821 struct block *b0, *b1, *tmp;
3822
3823 /* ip proto 'proto' */
3824 tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto);
3825 b0 = gen_ipfrag();
3826 gen_and(tmp, b0);
3827
3828 switch (dir) {
3829 case Q_SRC:
3830 b1 = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
3831 break;
3832
3833 case Q_DST:
3834 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
3835 break;
3836
3837 case Q_OR:
3838 case Q_DEFAULT:
3839 tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
3840 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
3841 gen_or(tmp, b1);
3842 break;
3843
3844 case Q_AND:
3845 tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
3846 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
3847 gen_and(tmp, b1);
3848 break;
3849
3850 default:
3851 abort();
3852 }
3853 gen_and(b0, b1);
3854
3855 return b1;
3856}
3857
3858static struct block *
3859gen_portrange(port1, port2, ip_proto, dir)
3860 int port1, port2;
3861 int ip_proto;
3862 int dir;
3863{
3864 struct block *b0, *b1, *tmp;
3865
3866 /* link proto ip */
3867 b0 = gen_linktype(ETHERTYPE_IP);
3868
3869 switch (ip_proto) {
3870 case IPPROTO_UDP:
3871 case IPPROTO_TCP:
3872 case IPPROTO_SCTP:
3873 b1 = gen_portrangeop(port1, port2, ip_proto, dir);
3874 break;
3875
3876 case PROTO_UNDEF:
3877 tmp = gen_portrangeop(port1, port2, IPPROTO_TCP, dir);
3878 b1 = gen_portrangeop(port1, port2, IPPROTO_UDP, dir);
3879 gen_or(tmp, b1);
3880 tmp = gen_portrangeop(port1, port2, IPPROTO_SCTP, dir);
3881 gen_or(tmp, b1);
3882 break;
3883
3884 default:
3885 abort();
3886 }
3887 gen_and(b0, b1);
3888 return b1;
3889}
3890
3891#ifdef INET6
3892static struct block *
3893gen_portrangeatom6(off, v1, v2)
3894 int off;
3895 bpf_int32 v1, v2;
3896{
3897 struct block *b1, *b2;
3898
3899 if (v1 > v2) {
3900 /*
3901 * Reverse the order of the ports, so v1 is the lower one.
3902 */
3903 bpf_int32 vtemp;
3904
3905 vtemp = v1;
3906 v1 = v2;
3907 v2 = vtemp;
3908 }
3909
3910 b1 = gen_cmp_ge(OR_TRAN_IPV6, off, BPF_H, v1);
3911 b2 = gen_cmp_le(OR_TRAN_IPV6, off, BPF_H, v2);
3912
3913 gen_and(b1, b2);
3914
3915 return b2;
3916}
3917
3918struct block *
3919gen_portrangeop6(port1, port2, proto, dir)
3920 int port1, port2;
3921 int proto;
3922 int dir;
3923{
3924 struct block *b0, *b1, *tmp;
3925
3926 /* ip6 proto 'proto' */
3927 b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto);
3928
3929 switch (dir) {
3930 case Q_SRC:
3931 b1 = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
3932 break;
3933
3934 case Q_DST:
3935 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
3936 break;
3937
3938 case Q_OR:
3939 case Q_DEFAULT:
3940 tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
3941 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
3942 gen_or(tmp, b1);
3943 break;
3944
3945 case Q_AND:
3946 tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
3947 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
3948 gen_and(tmp, b1);
3949 break;
3950
3951 default:
3952 abort();
3953 }
3954 gen_and(b0, b1);
3955
3956 return b1;
3957}
3958
3959static struct block *
3960gen_portrange6(port1, port2, ip_proto, dir)
3961 int port1, port2;
3962 int ip_proto;
3963 int dir;
3964{
3965 struct block *b0, *b1, *tmp;
3966
3967 /* link proto ip6 */
3968 b0 = gen_linktype(ETHERTYPE_IPV6);
3969
3970 switch (ip_proto) {
3971 case IPPROTO_UDP:
3972 case IPPROTO_TCP:
3973 case IPPROTO_SCTP:
3974 b1 = gen_portrangeop6(port1, port2, ip_proto, dir);
3975 break;
3976
3977 case PROTO_UNDEF:
3978 tmp = gen_portrangeop6(port1, port2, IPPROTO_TCP, dir);
3979 b1 = gen_portrangeop6(port1, port2, IPPROTO_UDP, dir);
3980 gen_or(tmp, b1);
3981 tmp = gen_portrangeop6(port1, port2, IPPROTO_SCTP, dir);
3982 gen_or(tmp, b1);
3983 break;
3984
3985 default:
3986 abort();
3987 }
3988 gen_and(b0, b1);
3989 return b1;
3990}
3991#endif /* INET6 */
3992
3993static int
3994lookup_proto(name, proto)
3995 register const char *name;
3996 register int proto;
3997{
3998 register int v;
3999
4000 switch (proto) {
--- 72 unchanged lines hidden (view full) ---
4073 b = gen_protochain(v, Q_IPV6, dir);
4074 gen_or(b0, b);
4075 return b;
4076 default:
4077 bpf_error("bad protocol applied for 'protochain'");
4078 /*NOTREACHED*/
4079 }
4080
4081 /*
4082 * We don't handle variable-length radiotap here headers yet.
4083 * We might want to add BPF instructions to do the protochain
4084 * work, to simplify that and, on platforms that have a BPF
4085 * interpreter with the new instructions, let the filtering
4086 * be done in the kernel. (We already require a modified BPF
4087 * engine to do the protochain stuff, to support backward
4088 * branches, and backward branch support is unlikely to appear
4089 * in kernel BPF engines.)
4090 */
4091 if (linktype == DLT_IEEE802_11_RADIO)
4092 bpf_error("'protochain' not supported with radiotap headers");
4093
4094 no_optimize = 1; /*this code is not compatible with optimzer yet */
4095
4096 /*
4097 * s[0] is a dummy entry to protect other BPF insn from damage
4098 * by s[fix] = foo with uninitialized variable "fix". It is somewhat
4099 * hard to find interdependency made by jump table fixup.
4100 */
4101 i = 0;
4102 s[i] = new_stmt(0); /*dummy*/
4103 i++;
4104
4105 switch (proto) {
--- 239 unchanged lines hidden (view full) ---
4345
4346 free_reg(reg2);
4347
4348 gen_and(b0, b);
4349 return b;
4350#endif
4351}
4352
4353/*
4354 * Generate code that checks whether the packet is a packet for protocol
4355 * <proto> and whether the type field in that protocol's header has
4356 * the value <v>, e.g. if <proto> is Q_IP, it checks whether it's an
4357 * IP packet and checks the protocol number in the IP header against <v>.
4358 *
4359 * If <proto> is Q_DEFAULT, i.e. just "proto" was specified, it checks
4360 * against Q_IP and Q_IPV6.
4361 */
4362static struct block *
4363gen_proto(v, proto, dir)
4364 int v;
4365 int proto;
4366 int dir;
4367{
4368 struct block *b0, *b1;
4369
--- 23 unchanged lines hidden (view full) ---
4393 * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and
4394 * RFC 2225 say that SNAP encapsulation is used, not LLC
4395 * encapsulation with LLCSAP_IP.
4396 *
4397 * So we always check for ETHERTYPE_IP.
4398 */
4399 b0 = gen_linktype(ETHERTYPE_IP);
4400#ifndef CHASE_CHAIN
4401 b1 = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)v);
4402#else
4403 b1 = gen_protochain(v, Q_IP);
4404#endif
4405 gen_and(b0, b1);
4406 return b1;
4407
4408 case Q_ISO:
4409 switch (linktype) {
--- 12 unchanged lines hidden (view full) ---
4422 * control field value of UI, i.e. 0x03 followed
4423 * by the NLPID.
4424 *
4425 * XXX - assumes a 2-byte Frame Relay header with
4426 * DLCI and flags. What if the address is longer?
4427 *
4428 * XXX - what about SNAP-encapsulated frames?
4429 */
4430 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | v);
4431 /*NOTREACHED*/
4432 break;
4433
4434 case DLT_C_HDLC:
4435 /*
4436 * Cisco uses an Ethertype lookalike - for OSI,
4437 * it's 0xfefe.
4438 */
4439 b0 = gen_linktype(LLCSAP_ISONS<<8 | LLCSAP_ISONS);
4440 /* OSI in C-HDLC is stuffed with a fudge byte */
4441 b1 = gen_cmp(OR_NET_NOSNAP, 1, BPF_B, (long)v);
4442 gen_and(b0, b1);
4443 return b1;
4444
4445 default:
4446 b0 = gen_linktype(LLCSAP_ISONS);
4447 b1 = gen_cmp(OR_NET_NOSNAP, 0, BPF_B, (long)v);
4448 gen_and(b0, b1);
4449 return b1;
4450 }
4451
4452 case Q_ISIS:
4453 b0 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
4454 /*
4455 * 4 is the offset of the PDU type relative to the IS-IS
4456 * header.
4457 */
4458 b1 = gen_cmp(OR_NET_NOSNAP, 4, BPF_B, (long)v);
4459 gen_and(b0, b1);
4460 return b1;
4461
4462 case Q_ARP:
4463 bpf_error("arp does not encapsulate another protocol");
4464 /* NOTREACHED */
4465
4466 case Q_RARP:
--- 58 unchanged lines hidden (view full) ---
4525 case Q_VRRP:
4526 bpf_error("'vrrp proto' is bogus");
4527 /* NOTREACHED */
4528
4529#ifdef INET6
4530 case Q_IPV6:
4531 b0 = gen_linktype(ETHERTYPE_IPV6);
4532#ifndef CHASE_CHAIN
4533 b1 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)v);
4534#else
4535 b1 = gen_protochain(v, Q_IPV6);
4536#endif
4537 gen_and(b0, b1);
4538 return b1;
4539
4540 case Q_ICMPV6:
4541 bpf_error("'icmp6 proto' is bogus");
--- 9 unchanged lines hidden (view full) ---
4551 bpf_error("'stp proto' is bogus");
4552
4553 case Q_IPX:
4554 bpf_error("'ipx proto' is bogus");
4555
4556 case Q_NETBEUI:
4557 bpf_error("'netbeui proto' is bogus");
4558
4559 case Q_RADIO:
4560 bpf_error("'radio proto' is bogus");
4561
4562 default:
4563 abort();
4564 /* NOTREACHED */
4565 }
4566 /* NOTREACHED */
4567}
4568
4569struct block *
--- 12 unchanged lines hidden (view full) ---
4582 int tproto6;
4583 struct sockaddr_in *sin;
4584 struct sockaddr_in6 *sin6;
4585 struct addrinfo *res, *res0;
4586 struct in6_addr mask128;
4587#endif /*INET6*/
4588 struct block *b, *tmp;
4589 int port, real_proto;
4590 int port1, port2;
4591
4592 switch (q.addr) {
4593
4594 case Q_NET:
4595 addr = pcap_nametonetaddr(name);
4596 if (addr == 0)
4597 bpf_error("unknown network '%s'", name);
4598 /* Left justify network addr and calculate its network mask */
--- 32 unchanged lines hidden (view full) ---
4631 if (eaddr == NULL)
4632 bpf_error(
4633 "unknown token ring host '%s'", name);
4634 b = gen_thostop(eaddr, dir);
4635 free(eaddr);
4636 return b;
4637
4638 case DLT_IEEE802_11:
4639 case DLT_IEEE802_11_RADIO_AVS:
4640 case DLT_IEEE802_11_RADIO:
4641 case DLT_PRISM_HEADER:
4642 eaddr = pcap_ether_hostton(name);
4643 if (eaddr == NULL)
4644 bpf_error(
4645 "unknown 802.11 host '%s'", name);
4646 b = gen_wlanhostop(eaddr, dir);
4647 free(eaddr);
4648 return b;
4649
--- 10 unchanged lines hidden (view full) ---
4660 if (!is_lane)
4661 break;
4662
4663 /*
4664 * Check that the packet doesn't begin
4665 * with an LE Control marker. (We've
4666 * already generated a test for LANE.)
4667 */
4668 tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS,
4669 BPF_H, 0xFF00);
4670 gen_not(tmp);
4671
4672 eaddr = pcap_ether_hostton(name);
4673 if (eaddr == NULL)
4674 bpf_error(
4675 "unknown ether host '%s'", name);
4676 b = gen_ehostop(eaddr, dir);
4677 gen_and(tmp, b);
--- 115 unchanged lines hidden (view full) ---
4793 {
4794 struct block *b;
4795 b = gen_port(port, real_proto, dir);
4796 gen_or(gen_port6(port, real_proto, dir), b);
4797 return b;
4798 }
4799#endif /* INET6 */
4800
4801 case Q_PORTRANGE:
4802 if (proto != Q_DEFAULT &&
4803 proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP)
4804 bpf_error("illegal qualifier of 'portrange'");
4805 if (pcap_nametoportrange(name, &port1, &port2, &real_proto) == 0)
4806 bpf_error("unknown port in range '%s'", name);
4807 if (proto == Q_UDP) {
4808 if (real_proto == IPPROTO_TCP)
4809 bpf_error("port in range '%s' is tcp", name);
4810 else if (real_proto == IPPROTO_SCTP)
4811 bpf_error("port in range '%s' is sctp", name);
4812 else
4813 /* override PROTO_UNDEF */
4814 real_proto = IPPROTO_UDP;
4815 }
4816 if (proto == Q_TCP) {
4817 if (real_proto == IPPROTO_UDP)
4818 bpf_error("port in range '%s' is udp", name);
4819 else if (real_proto == IPPROTO_SCTP)
4820 bpf_error("port in range '%s' is sctp", name);
4821 else
4822 /* override PROTO_UNDEF */
4823 real_proto = IPPROTO_TCP;
4824 }
4825 if (proto == Q_SCTP) {
4826 if (real_proto == IPPROTO_UDP)
4827 bpf_error("port in range '%s' is udp", name);
4828 else if (real_proto == IPPROTO_TCP)
4829 bpf_error("port in range '%s' is tcp", name);
4830 else
4831 /* override PROTO_UNDEF */
4832 real_proto = IPPROTO_SCTP;
4833 }
4834#ifndef INET6
4835 return gen_portrange(port1, port2, real_proto, dir);
4836#else
4837 {
4838 struct block *b;
4839 b = gen_portrange(port1, port2, real_proto, dir);
4840 gen_or(gen_portrange6(port1, port2, real_proto, dir), b);
4841 return b;
4842 }
4843#endif /* INET6 */
4844
4845 case Q_GATEWAY:
4846#ifndef INET6
4847 eaddr = pcap_ether_hostton(name);
4848 if (eaddr == NULL)
4849 bpf_error("unknown ether host: %s", name);
4850
4851 alist = pcap_nametoaddr(name);
4852 if (alist == NULL || *alist == NULL)
--- 131 unchanged lines hidden (view full) ---
4984 {
4985 struct block *b;
4986 b = gen_port((int)v, proto, dir);
4987 gen_or(gen_port6((int)v, proto, dir), b);
4988 return b;
4989 }
4990#endif /* INET6 */
4991
4992 case Q_PORTRANGE:
4993 if (proto == Q_UDP)
4994 proto = IPPROTO_UDP;
4995 else if (proto == Q_TCP)
4996 proto = IPPROTO_TCP;
4997 else if (proto == Q_SCTP)
4998 proto = IPPROTO_SCTP;
4999 else if (proto == Q_DEFAULT)
5000 proto = PROTO_UNDEF;
5001 else
5002 bpf_error("illegal qualifier of 'portrange'");
5003
5004#ifndef INET6
5005 return gen_portrange((int)v, (int)v, proto, dir);
5006#else
5007 {
5008 struct block *b;
5009 b = gen_portrange((int)v, (int)v, proto, dir);
5010 gen_or(gen_portrange6((int)v, (int)v, proto, dir), b);
5011 return b;
5012 }
5013#endif /* INET6 */
5014
5015 case Q_GATEWAY:
5016 bpf_error("'gateway' requires a name");
5017 /* NOTREACHED */
5018
5019 case Q_PROTO:
5020 return gen_proto((int)v, proto, dir);
5021
5022 case Q_PROTOCHAIN:
--- 78 unchanged lines hidden (view full) ---
5101
5102 if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) {
5103 if (linktype == DLT_EN10MB)
5104 return gen_ehostop(eaddr, (int)q.dir);
5105 if (linktype == DLT_FDDI)
5106 return gen_fhostop(eaddr, (int)q.dir);
5107 if (linktype == DLT_IEEE802)
5108 return gen_thostop(eaddr, (int)q.dir);
5109 if (linktype == DLT_IEEE802_11 ||
5110 linktype == DLT_IEEE802_11_RADIO_AVS ||
5111 linktype == DLT_IEEE802_11_RADIO ||
5112 linktype == DLT_PRISM_HEADER)
5113 return gen_wlanhostop(eaddr, (int)q.dir);
5114 if (linktype == DLT_SUNATM && is_lane) {
5115 /*
5116 * Check that the packet doesn't begin with an
5117 * LE Control marker. (We've already generated
5118 * a test for LANE.)
5119 */
5120 tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
5121 0xFF00);
5122 gen_not(tmp);
5123
5124 /*
5125 * Now check the MAC address.
5126 */
5127 b = gen_ehostop(eaddr, (int)q.dir);
5128 gen_and(tmp, b);
5129 return b;
--- 36 unchanged lines hidden (view full) ---
5166{
5167 struct slist *s;
5168
5169 s = new_stmt(BPF_LD|BPF_MEM);
5170 s->s.k = a->regno;
5171 return s;
5172}
5173
5174/*
5175 * Modify "index" to use the value stored into its register as an
5176 * offset relative to the beginning of the header for the protocol
5177 * "proto", and allocate a register and put an item "size" bytes long
5178 * (1, 2, or 4) at that offset into that register, making it the register
5179 * for "index".
5180 */
5181struct arth *
5182gen_load(proto, index, size)
5183 int proto;
5184 struct arth *index;
5185 int size;
5186{
5187 struct slist *s, *tmp;
5188 struct block *b;
--- 16 unchanged lines hidden (view full) ---
5205 case 4:
5206 size = BPF_W;
5207 break;
5208 }
5209 switch (proto) {
5210 default:
5211 bpf_error("unsupported index operation");
5212
5213 case Q_RADIO:
5214 /*
5215 * The offset is relative to the beginning of the packet
5216 * data, if we have a radio header. (If we don't, this
5217 * is an error.)
5218 */
5219 if (linktype != DLT_IEEE802_11_RADIO_AVS &&
5220 linktype != DLT_IEEE802_11_RADIO &&
5221 linktype != DLT_PRISM_HEADER)
5222 bpf_error("radio information not present in capture");
5223
5224 /*
5225 * Load into the X register the offset computed into the
5226 * register specifed by "index".
5227 */
5228 s = xfer_to_x(index);
5229
5230 /*
5231 * Load the item at that offset.
5232 */
5233 tmp = new_stmt(BPF_LD|BPF_IND|size);
5234 sappend(s, tmp);
5235 sappend(index->s, s);
5236 break;
5237
5238 case Q_LINK:
5239 /*
5240 * The offset is relative to the beginning of
5241 * the link-layer header.
5242 *
5243 * XXX - what about ATM LANE? Should the index be
5244 * relative to the beginning of the AAL5 frame, so
5245 * that 0 refers to the beginning of the LE Control
5246 * field, or relative to the beginning of the LAN
5247 * frame, so that 0 refers, for Ethernet LANE, to
5248 * the beginning of the destination address?
5249 */
5250 s = gen_llprefixlen();
5251
5252 /*
5253 * If "s" is non-null, it has code to arrange that the
5254 * X register contains the length of the prefix preceding
5255 * the link-layer header. Add to it the offset computed
5256 * into the register specified by "index", and move that
5257 * into the X register. Otherwise, just load into the X
5258 * register the offset computed into the register specifed
5259 * by "index".
5260 */
5261 if (s != NULL) {
5262 sappend(s, xfer_to_a(index));
5263 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
5264 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
5265 } else
5266 s = xfer_to_x(index);
5267
5268 /*
5269 * Load the item at the sum of the offset we've put in the
5270 * X register and the offset of the start of the link
5271 * layer header (which is 0 if the radio header is
5272 * variable-length; that header length is what we put
5273 * into the X register and then added to the index).
5274 */
5275 tmp = new_stmt(BPF_LD|BPF_IND|size);
5276 tmp->s.k = off_ll;
5277 sappend(s, tmp);
5278 sappend(index->s, s);
5279 break;
5280
5281 case Q_IP:
5282 case Q_ARP:
5283 case Q_RARP:
5284 case Q_ATALK:
5285 case Q_DECNET:
5286 case Q_SCA:
5287 case Q_LAT:
5288 case Q_MOPRC:
5289 case Q_MOPDL:
5290#ifdef INET6
5291 case Q_IPV6:
5292#endif
5293 /*
5294 * The offset is relative to the beginning of
5295 * the network-layer header.
5296 * XXX - are there any cases where we want
5297 * off_nl_nosnap?
5298 */
5299 s = gen_llprefixlen();
5300
5301 /*
5302 * If "s" is non-null, it has code to arrange that the
5303 * X register contains the length of the prefix preceding
5304 * the link-layer header. Add to it the offset computed
5305 * into the register specified by "index", and move that
5306 * into the X register. Otherwise, just load into the X
5307 * register the offset computed into the register specifed
5308 * by "index".
5309 */
5310 if (s != NULL) {
5311 sappend(s, xfer_to_a(index));
5312 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
5313 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
5314 } else
5315 s = xfer_to_x(index);
5316
5317 /*
5318 * Load the item at the sum of the offset we've put in the
5319 * X register and the offset of the start of the network
5320 * layer header.
5321 */
5322 tmp = new_stmt(BPF_LD|BPF_IND|size);
5323 tmp->s.k = off_nl;
5324 sappend(s, tmp);
5325 sappend(index->s, s);
5326
5327 /*
5328 * Do the computation only if the packet contains
5329 * the protocol in question.
5330 */
5331 b = gen_proto_abbrev(proto);
5332 if (index->b)
5333 gen_and(index->b, b);
5334 index->b = b;
5335 break;
5336
5337 case Q_SCTP:
5338 case Q_TCP:
5339 case Q_UDP:
5340 case Q_ICMP:
5341 case Q_IGMP:
5342 case Q_IGRP:
5343 case Q_PIM:
5344 case Q_VRRP:
5345 /*
5346 * The offset is relative to the beginning of
5347 * the transport-layer header.
5348 * XXX - are there any cases where we want
5349 * off_nl_nosnap?
5350 * XXX - we should, if we're built with
5351 * IPv6 support, generate code to load either
5352 * IPv4, IPv6, or both, as appropriate.
5353 */
5354 s = gen_loadx_iphdrlen();
5355
5356 /*
5357 * The X register now contains the sum of the offset
5358 * of the beginning of the link-layer header and
5359 * the length of the network-layer header. Load
5360 * into the A register the offset relative to
5361 * the beginning of the transport layer header,
5362 * add the X register to that, move that to the
5363 * X register, and load with an offset from the
5364 * X register equal to the offset of the network
5365 * layer header relative to the beginning of
5366 * the link-layer header.
5367 */
5368 sappend(s, xfer_to_a(index));
5369 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
5370 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
5371 sappend(s, tmp = new_stmt(BPF_LD|BPF_IND|size));
5372 tmp->s.k = off_nl;
5373 sappend(index->s, s);
5374
5375 /*
5376 * Do the computation only if the packet contains
5377 * the protocol in question - which is true only
5378 * if this is an IP datagram and is the first or
5379 * only fragment of that datagram.
5380 */
5381 gen_and(gen_proto_abbrev(proto), b = gen_ipfrag());
5382 if (index->b)
5383 gen_and(index->b, b);
5384#ifdef INET6
5385 gen_and(gen_proto_abbrev(Q_IP), b);
5386#endif
5387 index->b = b;
5388 break;
--- 209 unchanged lines hidden (view full) ---
5598 struct block *b;
5599
5600 b = gen_len(BPF_JGT, n);
5601 gen_not(b);
5602
5603 return b;
5604}
5605
5606/*
5607 * This is for "byte {idx} {op} {val}"; "idx" is treated as relative to
5608 * the beginning of the link-layer header.
5609 * XXX - that means you can't test values in the radiotap header, but
5610 * as that header is difficult if not impossible to parse generally
5611 * without a loop, that might not be a severe problem. A new keyword
5612 * "radio" could be added for that, although what you'd really want
5613 * would be a way of testing particular radio header values, which
5614 * would generate code appropriate to the radio header in question.
5615 */
5616struct block *
5617gen_byteop(op, idx, val)
5618 int op, idx, val;
5619{
5620 struct block *b;
5621 struct slist *s;
5622
5623 switch (op) {
5624 default:
5625 abort();
5626
5627 case '=':
5628 return gen_cmp(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
5629
5630 case '<':
5631 b = gen_cmp_lt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
5632 return b;
5633
5634 case '>':
5635 b = gen_cmp_gt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
5636 return b;
5637
5638 case '|':
5639 s = new_stmt(BPF_ALU|BPF_OR|BPF_K);
5640 break;
5641
5642 case '&':
5643 s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
--- 24 unchanged lines hidden (view full) ---
5668 if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX)
5669 return gen_ahostop(abroadcast, Q_DST);
5670 if (linktype == DLT_EN10MB)
5671 return gen_ehostop(ebroadcast, Q_DST);
5672 if (linktype == DLT_FDDI)
5673 return gen_fhostop(ebroadcast, Q_DST);
5674 if (linktype == DLT_IEEE802)
5675 return gen_thostop(ebroadcast, Q_DST);
5676 if (linktype == DLT_IEEE802_11 ||
5677 linktype == DLT_IEEE802_11_RADIO_AVS ||
5678 linktype == DLT_IEEE802_11_RADIO ||
5679 linktype == DLT_PRISM_HEADER)
5680 return gen_wlanhostop(ebroadcast, Q_DST);
5681 if (linktype == DLT_IP_OVER_FC)
5682 return gen_ipfchostop(ebroadcast, Q_DST);
5683 if (linktype == DLT_SUNATM && is_lane) {
5684 /*
5685 * Check that the packet doesn't begin with an
5686 * LE Control marker. (We've already generated
5687 * a test for LANE.)
5688 */
5689 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
5690 0xFF00);
5691 gen_not(b1);
5692
5693 /*
5694 * Now check the MAC address.
5695 */
5696 b0 = gen_ehostop(ebroadcast, Q_DST);
5697 gen_and(b1, b0);
5698 return b0;
5699 }
5700 bpf_error("not a broadcast link");
5701 break;
5702
5703 case Q_IP:
5704 b0 = gen_linktype(ETHERTYPE_IP);
5705 hostmask = ~netmask;
5706 b1 = gen_mcmp(OR_NET, 16, BPF_W, (bpf_int32)0, hostmask);
5707 b2 = gen_mcmp(OR_NET, 16, BPF_W,
5708 (bpf_int32)(~0 & hostmask), hostmask);
5709 gen_or(b1, b2);
5710 gen_and(b0, b2);
5711 return b2;
5712 }
5713 bpf_error("only link-layer/IP broadcast filters supported");
5714 /* NOTREACHED */
5715}
--- 5 unchanged lines hidden (view full) ---
5721static struct block *
5722gen_mac_multicast(offset)
5723 int offset;
5724{
5725 register struct block *b0;
5726 register struct slist *s;
5727
5728 /* link[offset] & 1 != 0 */
5729 s = gen_load_a(OR_LINK, offset, BPF_B);
5730 b0 = new_block(JMP(BPF_JSET));
5731 b0->s.k = 1;
5732 b0->stmts = s;
5733 return b0;
5734}
5735
5736struct block *
5737gen_multicast(proto)
--- 25 unchanged lines hidden (view full) ---
5763 return gen_mac_multicast(1);
5764 }
5765
5766 if (linktype == DLT_IEEE802) {
5767 /* tr[2] & 1 != 0 */
5768 return gen_mac_multicast(2);
5769 }
5770
5771 if (linktype == DLT_IEEE802_11 ||
5772 linktype == DLT_IEEE802_11_RADIO_AVS ||
5773 linktype == DLT_IEEE802_11_RADIO ||
5774 linktype == DLT_PRISM_HEADER) {
5775 /*
5776 * Oh, yuk.
5777 *
5778 * For control frames, there is no DA.
5779 *
5780 * For management frames, DA is at an
5781 * offset of 4 from the beginning of
5782 * the packet.
--- 5 unchanged lines hidden (view full) ---
5788 * if To DS is set.
5789 */
5790
5791 /*
5792 * Generate the tests to be done for data frames.
5793 *
5794 * First, check for To DS set, i.e. "link[1] & 0x01".
5795 */
5796 s = gen_load_a(OR_LINK, 1, BPF_B);
5797 b1 = new_block(JMP(BPF_JSET));
5798 b1->s.k = 0x01; /* To DS */
5799 b1->stmts = s;
5800
5801 /*
5802 * If To DS is set, the DA is at 16.
5803 */
5804 b0 = gen_mac_multicast(16);
5805 gen_and(b1, b0);
5806
5807 /*
5808 * Now, check for To DS not set, i.e. check
5809 * "!(link[1] & 0x01)".
5810 */
5811 s = gen_load_a(OR_LINK, 1, BPF_B);
5812 b2 = new_block(JMP(BPF_JSET));
5813 b2->s.k = 0x01; /* To DS */
5814 b2->stmts = s;
5815 gen_not(b2);
5816
5817 /*
5818 * If To DS is not set, the DA is at 4.
5819 */
--- 5 unchanged lines hidden (view full) ---
5825 * the complete set of checks for data frames.
5826 */
5827 gen_or(b1, b0);
5828
5829 /*
5830 * Now check for a data frame.
5831 * I.e, check "link[0] & 0x08".
5832 */
5833 s = gen_load_a(OR_LINK, 0, BPF_B);
5834 b1 = new_block(JMP(BPF_JSET));
5835 b1->s.k = 0x08;
5836 b1->stmts = s;
5837
5838 /*
5839 * AND that with the checks done for data frames.
5840 */
5841 gen_and(b1, b0);
5842
5843 /*
5844 * If the high-order bit of the type value is 0, this
5845 * is a management frame.
5846 * I.e, check "!(link[0] & 0x08)".
5847 */
5848 s = gen_load_a(OR_LINK, 0, BPF_B);
5849 b2 = new_block(JMP(BPF_JSET));
5850 b2->s.k = 0x08;
5851 b2->stmts = s;
5852 gen_not(b2);
5853
5854 /*
5855 * For management frames, the DA is at 4.
5856 */
--- 10 unchanged lines hidden (view full) ---
5867 /*
5868 * If the low-order bit of the type value is 1,
5869 * this is either a control frame or a frame
5870 * with a reserved type, and thus not a
5871 * frame with an SA.
5872 *
5873 * I.e., check "!(link[0] & 0x04)".
5874 */
5875 s = gen_load_a(OR_LINK, 0, BPF_B);
5876 b1 = new_block(JMP(BPF_JSET));
5877 b1->s.k = 0x04;
5878 b1->stmts = s;
5879 gen_not(b1);
5880
5881 /*
5882 * AND that with the checks for data and management
5883 * frames.
--- 8 unchanged lines hidden (view full) ---
5892 }
5893
5894 if (linktype == DLT_SUNATM && is_lane) {
5895 /*
5896 * Check that the packet doesn't begin with an
5897 * LE Control marker. (We've already generated
5898 * a test for LANE.)
5899 */
5900 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
5901 0xFF00);
5902 gen_not(b1);
5903
5904 /* ether[off_mac] & 1 != 0 */
5905 b0 = gen_mac_multicast(off_mac);
5906 gen_and(b1, b0);
5907 return b0;
5908 }
5909
5910 /* Link not known to support multicasts */
5911 break;
5912
5913 case Q_IP:
5914 b0 = gen_linktype(ETHERTYPE_IP);
5915 b1 = gen_cmp_ge(OR_NET, 16, BPF_B, (bpf_int32)224);
5916 gen_and(b0, b1);
5917 return b1;
5918
5919#ifdef INET6
5920 case Q_IPV6:
5921 b0 = gen_linktype(ETHERTYPE_IPV6);
5922 b1 = gen_cmp(OR_NET, 24, BPF_B, (bpf_int32)255);
5923 gen_and(b0, b1);
5924 return b1;
5925#endif /* INET6 */
5926 }
5927 bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel");
5928 /* NOTREACHED */
5929}
5930
--- 19 unchanged lines hidden (view full) ---
5950 dir);
5951 break;
5952
5953 case DLT_LINUX_SLL:
5954 if (dir) {
5955 /*
5956 * Match packets sent by this machine.
5957 */
5958 b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_OUTGOING);
5959 } else {
5960 /*
5961 * Match packets sent to this machine.
5962 * (No broadcast or multicast packets, or
5963 * packets sent to some other machine and
5964 * received promiscuously.)
5965 *
5966 * XXX - packets sent to other machines probably
5967 * shouldn't be matched, but what about broadcast
5968 * or multicast packets we received?
5969 */
5970 b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_HOST);
5971 }
5972 break;
5973
5974 case DLT_PFLOG:
5975 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, dir), BPF_B,
5976 (bpf_int32)((dir == 0) ? PF_IN : PF_OUT));
5977 break;
5978
5979 case DLT_PPP_PPPD:
5980 if (dir) {
5981 /* match outgoing packets */
5982 b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_OUT);
5983 } else {
5984 /* match incoming packets */
5985 b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_IN);
5986 }
5987 break;
5988
5989 case DLT_JUNIPER_MLFR:
5990 case DLT_JUNIPER_MLPPP:
5991 case DLT_JUNIPER_ATM1:
5992 case DLT_JUNIPER_ATM2:
5993 case DLT_JUNIPER_PPPOE:
5994 case DLT_JUNIPER_PPPOE_ATM:
5995 case DLT_JUNIPER_GGSN:
5996 case DLT_JUNIPER_ES:
5997 case DLT_JUNIPER_MONITOR:
5998 case DLT_JUNIPER_SERVICES:
5999 /* juniper flags (including direction) are stored
6000 * the byte after the 3-byte magic number */
6001 if (dir) {
6002 /* match outgoing packets */
6003 b0 = gen_mcmp(OR_LINK, 3, BPF_B, 0, 0x01);
6004 } else {
6005 /* match incoming packets */
6006 b0 = gen_mcmp(OR_LINK, 3, BPF_B, 1, 0x01);
6007 }
6008 break;
6009
6010 default:
6011 bpf_error("inbound/outbound not supported on linktype %d",
6012 linktype);
6013 b0 = NULL;
6014 /* NOTREACHED */
--- 15 unchanged lines hidden (view full) ---
6030 bpf_error("ifname not supported on linktype 0x%x", linktype);
6031 /* NOTREACHED */
6032 }
6033 if (strlen(ifname) >= len) {
6034 bpf_error("ifname interface names can only be %d characters",
6035 len-1);
6036 /* NOTREACHED */
6037 }
6038 b0 = gen_bcmp(OR_LINK, off, strlen(ifname), (const u_char *)ifname);
6039 return (b0);
6040}
6041
6042/* PF firewall log matched interface */
6043struct block *
6044gen_pf_ruleset(char *ruleset)
6045{
6046 struct block *b0;
6047
6048 if (linktype != DLT_PFLOG) {
6049 bpf_error("ruleset not supported on linktype 0x%x", linktype);
6050 /* NOTREACHED */
6051 }
6052 if (strlen(ruleset) >= sizeof(((struct pfloghdr *)0)->ruleset)) {
6053 bpf_error("ruleset names can only be %ld characters",
6054 (long)(sizeof(((struct pfloghdr *)0)->ruleset) - 1));
6055 /* NOTREACHED */
6056 }
6057 b0 = gen_bcmp(OR_LINK, offsetof(struct pfloghdr, ruleset),
6058 strlen(ruleset), (const u_char *)ruleset);
6059 return (b0);
6060}
6061
6062/* PF firewall log rule number */
6063struct block *
6064gen_pf_rnr(int rnr)
6065{
6066 struct block *b0;
6067
6068 if (linktype == DLT_PFLOG) {
6069 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, rulenr), BPF_W,
6070 (bpf_int32)rnr);
6071 } else {
6072 bpf_error("rnr not supported on linktype 0x%x", linktype);
6073 /* NOTREACHED */
6074 }
6075
6076 return (b0);
6077}
--- 4 unchanged lines hidden (view full) ---
6082{
6083 struct block *b0;
6084
6085 if (linktype != DLT_PFLOG) {
6086 bpf_error("srnr not supported on linktype 0x%x", linktype);
6087 /* NOTREACHED */
6088 }
6089
6090 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, subrulenr), BPF_W,
6091 (bpf_int32)srnr);
6092 return (b0);
6093}
6094
6095/* PF firewall log reason code */
6096struct block *
6097gen_pf_reason(int reason)
6098{
6099 struct block *b0;
6100
6101 if (linktype == DLT_PFLOG) {
6102 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, reason), BPF_B,
6103 (bpf_int32)reason);
6104 } else {
6105 bpf_error("reason not supported on linktype 0x%x", linktype);
6106 /* NOTREACHED */
6107 }
6108
6109 return (b0);
6110}
6111
6112/* PF firewall log action */
6113struct block *
6114gen_pf_action(int action)
6115{
6116 struct block *b0;
6117
6118 if (linktype == DLT_PFLOG) {
6119 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, action), BPF_B,
6120 (bpf_int32)action);
6121 } else {
6122 bpf_error("action not supported on linktype 0x%x", linktype);
6123 /* NOTREACHED */
6124 }
6125
6126 return (b0);
6127}
--- 16 unchanged lines hidden (view full) ---
6144 register const u_char *eaddr;
6145 register int dir;
6146{
6147 register struct block *b0, *b1;
6148
6149 switch (dir) {
6150 /* src comes first, different from Ethernet */
6151 case Q_SRC:
6152 return gen_bcmp(OR_LINK, 0, 1, eaddr);
6153
6154 case Q_DST:
6155 return gen_bcmp(OR_LINK, 1, 1, eaddr);
6156
6157 case Q_AND:
6158 b0 = gen_ahostop(eaddr, Q_SRC);
6159 b1 = gen_ahostop(eaddr, Q_DST);
6160 gen_and(b0, b1);
6161 return b1;
6162
6163 case Q_DEFAULT:
--- 13 unchanged lines hidden (view full) ---
6177struct block *
6178gen_vlan(vlan_num)
6179 int vlan_num;
6180{
6181 struct block *b0;
6182
6183 /*
6184 * Change the offsets to point to the type and data fields within
6185 * the VLAN packet. Just increment the offsets, so that we
6186 * can support a hierarchy, e.g. "vlan 300 && vlan 200" to
6187 * capture VLAN 200 encapsulated within VLAN 100.
6188 *
6189 * XXX - this is a bit of a kludge. If we were to split the
6190 * compiler into a parser that parses an expression and
6191 * generates an expression tree, and a code generator that
6192 * takes an expression tree (which could come from our
6193 * parser or from some other parser) and generates BPF code,
6194 * we could perhaps make the offsets parameters of routines
6195 * and, in the handler for an "AND" node, pass to subnodes
6196 * other than the VLAN node the adjusted offsets.
6197 *
6198 * This would mean that "vlan" would, instead of changing the
6199 * behavior of *all* tests after it, change only the behavior
6200 * of tests ANDed with it. That would change the documented
6201 * semantics of "vlan", which might break some expressions.
6202 * However, it would mean that "(vlan and ip) or ip" would check
6203 * both for VLAN-encapsulated IP and IP-over-Ethernet, rather than
6204 * checking only for VLAN-encapsulated IP, so that could still
6205 * be considered worth doing; it wouldn't break expressions
6206 * that are of the form "vlan and ..." or "vlan N and ...",
6207 * which I suspect are the most common expressions involving
6208 * "vlan". "vlan or ..." doesn't necessarily do what the user
6209 * would really want, now, as all the "or ..." tests would
6210 * be done assuming a VLAN, even though the "or" could be viewed
6211 * as meaning "or, if this isn't a VLAN packet...".
6212 */
6213 orig_linktype = off_linktype; /* save original values */
6214 orig_nl = off_nl;
6215
6216 switch (linktype) {
6217
6218 case DLT_EN10MB:
6219 off_linktype += 4;
6220 off_nl_nosnap += 4;
6221 off_nl += 4;
6222 break;
6223
6224 default:
6225 bpf_error("no VLAN support for data link type %d",
6226 linktype);
6227 /*NOTREACHED*/
6228 }
6229
6230 /* check for VLAN */
6231 b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H, (bpf_int32)ETHERTYPE_8021Q);
6232
6233 /* If a specific VLAN is requested, check VLAN id */
6234 if (vlan_num >= 0) {
6235 struct block *b1;
6236
6237 b1 = gen_mcmp(OR_LINK, orig_nl, BPF_H, (bpf_int32)vlan_num,
6238 0x0fff);
6239 gen_and(b0, b1);
6240 b0 = b1;
6241 }
6242
6243 return (b0);
6244}
6245
6246/*
6247 * support for MPLS
6248 */
6249struct block *
6250gen_mpls(label_num)
6251 int label_num;
6252{
6253 struct block *b0;
6254
6255 /*
6256 * Change the offsets to point to the type and data fields within
6257 * the MPLS packet. Just increment the offsets, so that we
6258 * can support a hierarchy, e.g. "mpls 100000 && mpls 1024" to
6259 * capture packets with an outer label of 100000 and an inner
6260 * label of 1024.
6261 *
6262 * XXX - this is a bit of a kludge. See comments in gen_vlan().
6263 */
6264 orig_linktype = off_linktype; /* save original values */
6265 orig_nl = off_nl;
6266
6267 switch (linktype) {
6268
6269 case DLT_C_HDLC: /* fall through */
6270 case DLT_EN10MB:
6271 off_nl_nosnap += 4;
6272 off_nl += 4;
6273
6274 b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H,
6275 (bpf_int32)ETHERTYPE_MPLS);
6276 break;
6277
6278 case DLT_PPP:
6279 off_nl_nosnap += 4;
6280 off_nl += 4;
6281
6282 b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H,
6283 (bpf_int32)PPP_MPLS_UCAST);
6284 break;
6285
6286 /* FIXME add other DLT_s ...
6287 * for Frame-Relay/and ATM this may get messy due to SNAP headers
6288 * leave it for now */
6289
6290 default:
6291 bpf_error("no MPLS support for data link type %d",
6292 linktype);
6293 b0 = NULL;
6294 /*NOTREACHED*/
6295 break;
6296 }
6297
6298 /* If a specific MPLS label is requested, check it */
6299 if (label_num >= 0) {
6300 struct block *b1;
6301
6302 label_num = label_num << 12; /* label is shifted 12 bits on the wire */
6303 b1 = gen_mcmp(OR_LINK, orig_nl, BPF_W, (bpf_int32)label_num,
6304 0xfffff000); /* only compare the first 20 bits */
6305 gen_and(b0, b1);
6306 b0 = b1;
6307 }
6308
6309 return (b0);
6310}
6311
6312struct block *
6313gen_atmfield_code(atmfield, jvalue, jtype, reverse)
6314 int atmfield;
6315 bpf_int32 jvalue;
6316 bpf_u_int32 jtype;
6317 int reverse;
6318{
6319 struct block *b0;
6320
6321 switch (atmfield) {
6322
6323 case A_VPI:
6324 if (!is_atm)
6325 bpf_error("'vpi' supported only on raw ATM");
6326 if (off_vpi == (u_int)-1)
6327 abort();
6328 b0 = gen_ncmp(OR_LINK, off_vpi, BPF_B, 0xffffffff, jtype,
6329 reverse, jvalue);
6330 break;
6331
6332 case A_VCI:
6333 if (!is_atm)
6334 bpf_error("'vci' supported only on raw ATM");
6335 if (off_vci == (u_int)-1)
6336 abort();
6337 b0 = gen_ncmp(OR_LINK, off_vci, BPF_H, 0xffffffff, jtype,
6338 reverse, jvalue);
6339 break;
6340
6341 case A_PROTOTYPE:
6342 if (off_proto == (u_int)-1)
6343 abort(); /* XXX - this isn't on FreeBSD */
6344 b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0x0f, jtype,
6345 reverse, jvalue);
6346 break;
6347
6348 case A_MSGTYPE:
6349 if (off_payload == (u_int)-1)
6350 abort();
6351 b0 = gen_ncmp(OR_LINK, off_payload + MSG_TYPE_POS, BPF_B,
6352 0xffffffff, jtype, reverse, jvalue);
6353 break;
6354
6355 case A_CALLREFTYPE:
6356 if (!is_atm)
6357 bpf_error("'callref' supported only on raw ATM");
6358 if (off_proto == (u_int)-1)
6359 abort();
6360 b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0xffffffff,
6361 jtype, reverse, jvalue);
6362 break;
6363
6364 default:
6365 abort();
6366 }
6367 return b0;
6368}
6369
--- 93 unchanged lines hidden (view full) ---
6463 break;
6464
6465 default:
6466 abort();
6467 }
6468 return b1;
6469}
6470
6471struct block *
6472gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
6473 int mtp3field;
6474 bpf_u_int32 jvalue;
6475 bpf_u_int32 jtype;
6476 int reverse;
6477{
6478 struct block *b0;
6479 bpf_u_int32 val1 , val2 , val3;
6480
6481 switch (mtp3field) {
6482
6483 case M_SIO:
6484 if (off_sio == (u_int)-1)
6485 bpf_error("'sio' supported only on SS7");
6486 /* sio coded on 1 byte so max value 255 */
6487 if(jvalue > 255)
6488 bpf_error("sio value %u too big; max value = 255",
6489 jvalue);
6490 b0 = gen_ncmp(OR_PACKET, off_sio, BPF_B, 0xffffffff,
6491 (u_int)jtype, reverse, (u_int)jvalue);
6492 break;
6493
6494 case M_OPC:
6495 if (off_opc == (u_int)-1)
6496 bpf_error("'opc' supported only on SS7");
6497 /* opc coded on 14 bits so max value 16383 */
6498 if (jvalue > 16383)
6499 bpf_error("opc value %u too big; max value = 16383",
6500 jvalue);
6501 /* the following instructions are made to convert jvalue
6502 * to the form used to write opc in an ss7 message*/
6503 val1 = jvalue & 0x00003c00;
6504 val1 = val1 >>10;
6505 val2 = jvalue & 0x000003fc;
6506 val2 = val2 <<6;
6507 val3 = jvalue & 0x00000003;
6508 val3 = val3 <<22;
6509 jvalue = val1 + val2 + val3;
6510 b0 = gen_ncmp(OR_PACKET, off_opc, BPF_W, 0x00c0ff0f,
6511 (u_int)jtype, reverse, (u_int)jvalue);
6512 break;
6513
6514 case M_DPC:
6515 if (off_dpc == (u_int)-1)
6516 bpf_error("'dpc' supported only on SS7");
6517 /* dpc coded on 14 bits so max value 16383 */
6518 if (jvalue > 16383)
6519 bpf_error("dpc value %u too big; max value = 16383",
6520 jvalue);
6521 /* the following instructions are made to convert jvalue
6522 * to the forme used to write dpc in an ss7 message*/
6523 val1 = jvalue & 0x000000ff;
6524 val1 = val1 << 24;
6525 val2 = jvalue & 0x00003f00;
6526 val2 = val2 << 8;
6527 jvalue = val1 + val2;
6528 b0 = gen_ncmp(OR_PACKET, off_dpc, BPF_W, 0xff3f0000,
6529 (u_int)jtype, reverse, (u_int)jvalue);
6530 break;
6531
6532 case M_SLS:
6533 if (off_sls == (u_int)-1)
6534 bpf_error("'sls' supported only on SS7");
6535 /* sls coded on 4 bits so max value 15 */
6536 if (jvalue > 15)
6537 bpf_error("sls value %u too big; max value = 15",
6538 jvalue);
6539 /* the following instruction is made to convert jvalue
6540 * to the forme used to write sls in an ss7 message*/
6541 jvalue = jvalue << 4;
6542 b0 = gen_ncmp(OR_PACKET, off_sls, BPF_B, 0xf0,
6543 (u_int)jtype,reverse, (u_int)jvalue);
6544 break;
6545
6546 default:
6547 abort();
6548 }
6549 return b0;
6550}
6551
6552static struct block *
6553gen_msg_abbrev(type)
6554 int type;
6555{
6556 struct block *b1;
6557
6558 /*
6559 * Q.2931 signalling protocol messages for handling virtual circuits
--- 102 unchanged lines hidden ---
2/*
3 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998
4 * The Regents of the University of California. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that: (1) source code distributions
8 * retain the above copyright notice and this paragraph in its entirety, (2)
--- 5 unchanged lines hidden (view full) ---
14 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
15 * the University nor the names of its contributors may be used to endorse
16 * or promote products derived from this software without specific prior
17 * written permission.
18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
19 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
21 *
22 * $FreeBSD: head/contrib/libpcap/gencode.c 147897 2005-07-11 03:43:25Z sam $
23 */
24#ifndef lint
25static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.24 2005/06/20 21:52:53 guy Exp $ (LBL)";
27#endif
28
29#ifdef HAVE_CONFIG_H
30#include "config.h"
31#endif
32
33#ifdef WIN32
34#include <pcap-stdinc.h>
--- 64 unchanged lines hidden (view full) ---
99
100#define JMP(c) ((c)|BPF_JMP|BPF_K)
101
102/* Locals */
103static jmp_buf top_ctx;
104static pcap_t *bpf_pcap;
105
106/* Hack for updating VLAN, MPLS offsets. */
107static u_int orig_linktype = -1U, orig_nl = -1U;
108
109/* XXX */
110#ifdef PCAP_FDDIPAD
111static int pcap_fddipad;
112#endif
113
114/* VARARGS */
115void
116bpf_error(const char *fmt, ...)
117{
118 va_list ap;
119
120 va_start(ap, fmt);
121 if (bpf_pcap != NULL)
122 (void)vsnprintf(pcap_geterr(bpf_pcap), PCAP_ERRBUF_SIZE,
123 fmt, ap);
124 va_end(ap);
--- 4 unchanged lines hidden (view full) ---
129static void init_linktype(pcap_t *);
130
131static int alloc_reg(void);
132static void free_reg(int);
133
134static struct block *root;
135
136/*
137 * Value passed to gen_load_a() to indicate what the offset argument
138 * is relative to.
139 */
140enum e_offrel {
141 OR_PACKET, /* relative to the beginning of the packet */
142 OR_LINK, /* relative to the link-layer header */
143 OR_NET, /* relative to the network-layer header */
144 OR_NET_NOSNAP, /* relative to the network-layer header, with no SNAP header at the link layer */
145 OR_TRAN_IPV4, /* relative to the transport-layer header, with IPv4 network layer */
146 OR_TRAN_IPV6 /* relative to the transport-layer header, with IPv6 network layer */
147};
148
149/*
150 * We divy out chunks of memory rather than call malloc each time so
151 * we don't have to worry about leaking memory. It's probably
152 * not a big deal if all this memory was wasted but if this ever
153 * goes into a library that would probably not be a good idea.
154 *
155 * XXX - this *is* in a library....
156 */
157#define NCHUNKS 16
--- 10 unchanged lines hidden (view full) ---
168static void freechunks(void);
169static inline struct block *new_block(int);
170static inline struct slist *new_stmt(int);
171static struct block *gen_retblk(int);
172static inline void syntax(void);
173
174static void backpatch(struct block *, struct block *);
175static void merge(struct block *, struct block *);
176static struct block *gen_cmp(enum e_offrel, u_int, u_int, bpf_int32);
177static struct block *gen_cmp_gt(enum e_offrel, u_int, u_int, bpf_int32);
178static struct block *gen_cmp_ge(enum e_offrel, u_int, u_int, bpf_int32);
179static struct block *gen_cmp_lt(enum e_offrel, u_int, u_int, bpf_int32);
180static struct block *gen_cmp_le(enum e_offrel, u_int, u_int, bpf_int32);
181static struct block *gen_mcmp(enum e_offrel, u_int, u_int, bpf_int32,
182 bpf_u_int32);
183static struct block *gen_bcmp(enum e_offrel, u_int, u_int, const u_char *);
184static struct block *gen_ncmp(enum e_offrel, bpf_u_int32, bpf_u_int32,
185 bpf_u_int32, bpf_u_int32, int, bpf_int32);
186static struct slist *gen_load_llrel(u_int, u_int);
187static struct slist *gen_load_a(enum e_offrel, u_int, u_int);
188static struct slist *gen_loadx_iphdrlen(void);
189static struct block *gen_uncond(int);
190static inline struct block *gen_true(void);
191static inline struct block *gen_false(void);
192static struct block *gen_ether_linktype(int);
193static struct block *gen_linux_sll_linktype(int);
194static void insert_radiotap_load_llprefixlen(struct block *);
195static void insert_load_llprefixlen(struct block *);
196static struct slist *gen_llprefixlen(void);
197static struct block *gen_linktype(int);
198static struct block *gen_snap(bpf_u_int32, bpf_u_int32, u_int);
199static struct block *gen_llc_linktype(int);
200static struct block *gen_hostop(bpf_u_int32, bpf_u_int32, int, int, u_int, u_int);
201#ifdef INET6
202static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int);
203#endif
204static struct block *gen_ahostop(const u_char *, int);
205static struct block *gen_ehostop(const u_char *, int);
206static struct block *gen_fhostop(const u_char *, int);
207static struct block *gen_thostop(const u_char *, int);
208static struct block *gen_wlanhostop(const u_char *, int);
209static struct block *gen_ipfchostop(const u_char *, int);
210static struct block *gen_dnhostop(bpf_u_int32, int);
211static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int);
212#ifdef INET6
213static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int);
214#endif
215#ifndef INET6
216static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int);
217#endif
218static struct block *gen_ipfrag(void);
219static struct block *gen_portatom(int, bpf_int32);
220static struct block *gen_portrangeatom(int, bpf_int32, bpf_int32);
221#ifdef INET6
222static struct block *gen_portatom6(int, bpf_int32);
223static struct block *gen_portrangeatom6(int, bpf_int32, bpf_int32);
224#endif
225struct block *gen_portop(int, int, int);
226static struct block *gen_port(int, int, int);
227struct block *gen_portrangeop(int, int, int, int);
228static struct block *gen_portrange(int, int, int, int);
229#ifdef INET6
230struct block *gen_portop6(int, int, int);
231static struct block *gen_port6(int, int, int);
232struct block *gen_portrangeop6(int, int, int, int);
233static struct block *gen_portrange6(int, int, int, int);
234#endif
235static int lookup_proto(const char *, int);
236static struct block *gen_protochain(int, int, int);
237static struct block *gen_proto(int, int, int);
238static struct slist *xfer_to_x(struct arth *);
239static struct slist *xfer_to_a(struct arth *);
240static struct block *gen_mac_multicast(int);
241static struct block *gen_len(int, int);
--- 235 unchanged lines hidden (view full) ---
477void
478finish_parse(p)
479 struct block *p;
480{
481 backpatch(p, gen_retblk(snaplen));
482 p->sense = !p->sense;
483 backpatch(p, gen_retblk(0));
484 root = p->head;
485
486 /*
487 * Insert before the statements of the first (root) block any
488 * statements needed to load the lengths of any variable-length
489 * headers into registers.
490 *
491 * XXX - a fancier strategy would be to insert those before the
492 * statements of all blocks that use those lengths and that
493 * have no predecessors that use them, so that we only compute
494 * the lengths if we need them. There might be even better
495 * approaches than that. However, as we're currently only
496 * handling variable-length radiotap headers, and as all
497 * filtering expressions other than raw link[M:N] tests
498 * require the length of that header, doing more for that
499 * header length isn't really worth the effort.
500 */
501 insert_load_llprefixlen(root);
502}
503
504void
505gen_and(b0, b1)
506 struct block *b0, *b1;
507{
508 backpatch(b0, b1->head);
509 b0->sense = !b0->sense;
--- 17 unchanged lines hidden (view full) ---
527void
528gen_not(b)
529 struct block *b;
530{
531 b->sense = !b->sense;
532}
533
534static struct block *
535gen_cmp(offrel, offset, size, v)
536 enum e_offrel offrel;
537 u_int offset, size;
538 bpf_int32 v;
539{
540 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JEQ, 0, v);
541}
542
543static struct block *
544gen_cmp_gt(offrel, offset, size, v)
545 enum e_offrel offrel;
546 u_int offset, size;
547 bpf_int32 v;
548{
549 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 0, v);
550}
551
552static struct block *
553gen_cmp_ge(offrel, offset, size, v)
554 enum e_offrel offrel;
555 u_int offset, size;
556 bpf_int32 v;
557{
558 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 0, v);
559}
560
561static struct block *
562gen_cmp_lt(offrel, offset, size, v)
563 enum e_offrel offrel;
564 u_int offset, size;
565 bpf_int32 v;
566{
567 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 1, v);
568}
569
570static struct block *
571gen_cmp_le(offrel, offset, size, v)
572 enum e_offrel offrel;
573 u_int offset, size;
574 bpf_int32 v;
575{
576 return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 1, v);
577}
578
579static struct block *
580gen_mcmp(offrel, offset, size, v, mask)
581 enum e_offrel offrel;
582 u_int offset, size;
583 bpf_int32 v;
584 bpf_u_int32 mask;
585{
586 return gen_ncmp(offrel, offset, size, mask, BPF_JEQ, 0, v);
587}
588
589static struct block *
590gen_bcmp(offrel, offset, size, v)
591 enum e_offrel offrel;
592 register u_int offset, size;
593 register const u_char *v;
594{
595 register struct block *b, *tmp;
596
597 b = NULL;
598 while (size >= 4) {
599 register const u_char *p = &v[size - 4];
600 bpf_int32 w = ((bpf_int32)p[0] << 24) |
601 ((bpf_int32)p[1] << 16) | ((bpf_int32)p[2] << 8) | p[3];
602
603 tmp = gen_cmp(offrel, offset + size - 4, BPF_W, w);
604 if (b != NULL)
605 gen_and(b, tmp);
606 b = tmp;
607 size -= 4;
608 }
609 while (size >= 2) {
610 register const u_char *p = &v[size - 2];
611 bpf_int32 w = ((bpf_int32)p[0] << 8) | p[1];
612
613 tmp = gen_cmp(offrel, offset + size - 2, BPF_H, w);
614 if (b != NULL)
615 gen_and(b, tmp);
616 b = tmp;
617 size -= 2;
618 }
619 if (size > 0) {
620 tmp = gen_cmp(offrel, offset, BPF_B, (bpf_int32)v[0]);
621 if (b != NULL)
622 gen_and(b, tmp);
623 b = tmp;
624 }
625 return b;
626}
627
628/*
629 * AND the field of size "size" at offset "offset" relative to the header
630 * specified by "offrel" with "mask", and compare it with the value "v"
631 * with the test specified by "jtype"; if "reverse" is true, the test
632 * should test the opposite of "jtype".
633 */
634static struct block *
635gen_ncmp(offrel, offset, size, mask, jtype, reverse, v)
636 enum e_offrel offrel;
637 bpf_int32 v;
638 bpf_u_int32 offset, size, mask, jtype;
639 int reverse;
640{
641 struct slist *s, *s2;
642 struct block *b;
643
644 s = gen_load_a(offrel, offset, size);
645
646 if (mask != 0xffffffff) {
647 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
648 s2->s.k = mask;
649 sappend(s, s2);
650 }
651
652 b = new_block(JMP(jtype));
653 b->stmts = s;
654 b->s.k = v;
655 if (reverse && (jtype == BPF_JGT || jtype == BPF_JGE))
656 gen_not(b);
657 return b;
658}
659
660/*
661 * Various code constructs need to know the layout of the data link
662 * layer. These variables give the necessary offsets from the beginning
663 * of the packet data.
664 *
665 * If the link layer has variable_length headers, the offsets are offsets
666 * from the end of the link-link-layer header, and "reg_ll_size" is
667 * the register number for a register containing the length of the
668 * link-layer header. Otherwise, "reg_ll_size" is -1.
669 */
670static int reg_ll_size;
671
672/*
673 * This is the offset of the beginning of the link-layer header.
674 * It's usually 0, except for 802.11 with a fixed-length radio header.
675 */
676static u_int off_ll;
677
678/*
679 * This is the offset of the beginning of the MAC-layer header.
680 * It's usually 0, except for ATM LANE.
681 */
682static u_int off_mac;
683
684/*
685 * "off_linktype" is the offset to information in the link-layer header
686 * giving the packet type.
--- 29 unchanged lines hidden (view full) ---
716/*
717 * These are offsets for the ATM pseudo-header.
718 */
719static u_int off_vpi;
720static u_int off_vci;
721static u_int off_proto;
722
723/*
724 * These are offsets for the MTP3 fields.
725 */
726static u_int off_sio;
727static u_int off_opc;
728static u_int off_dpc;
729static u_int off_sls;
730
731/*
732 * This is the offset of the first byte after the ATM pseudo_header,
733 * or -1 if there is no ATM pseudo-header.
734 */
735static u_int off_payload;
736
737/*
738 * These are offsets to the beginning of the network-layer header.
739 *
--- 36 unchanged lines hidden (view full) ---
776 off_mac = 0;
777 is_atm = 0;
778 is_lane = 0;
779 off_vpi = -1;
780 off_vci = -1;
781 off_proto = -1;
782 off_payload = -1;
783
784 off_sio = -1;
785 off_opc = -1;
786 off_dpc = -1;
787 off_sls = -1;
788
789 /*
790 * Also assume it's not 802.11 with a fixed-length radio header.
791 */
792 off_ll = 0;
793
794 orig_linktype = -1;
795 orig_nl = -1;
796
797 reg_ll_size = -1;
798
799 switch (linktype) {
800
801 case DLT_ARCNET:
802 off_linktype = 2;
803 off_nl = 6; /* XXX in reality, variable! */
804 off_nl_nosnap = 6; /* no 802.2 LLC */
805 return;
806
--- 141 unchanged lines hidden (view full) ---
948 * the 802.11 header, containing a bunch of additional
949 * information including radio-level information.
950 *
951 * The header is 144 bytes long.
952 *
953 * XXX - same variable-length header problem; at least
954 * the Prism header is fixed-length.
955 */
956 off_ll = 144;
957 off_linktype = 144+24;
958 off_nl = 144+32; /* Prism+802.11+802.2+SNAP */
959 off_nl_nosnap = 144+27; /* Prism+802.11+802.2 */
960 return;
961
962 case DLT_IEEE802_11_RADIO_AVS:
963 /*
964 * Same as 802.11, but with an additional header before
--- 4 unchanged lines hidden (view full) ---
969 * current incarnation.
970 *
971 * XXX - same variable-length header problem, only
972 * more so; this header is also variable-length,
973 * with the length being the 32-bit big-endian
974 * number at an offset of 4 from the beginning
975 * of the radio header.
976 */
977 off_ll = 64;
978 off_linktype = 64+24;
979 off_nl = 64+32; /* Radio+802.11+802.2+SNAP */
980 off_nl_nosnap = 64+27; /* Radio+802.11+802.2 */
981 return;
982
983 case DLT_IEEE802_11_RADIO:
984 /*
985 * Same as 802.11, but with an additional header before
986 * the 802.11 header, containing a bunch of additional
987 * information including radio-level information.
988 *
989 * The radiotap header is variable length, and we
990 * generate code to compute its length and store it
991 * in a register. These offsets are relative to the
992 * beginning of the 802.11 header.
993 */
994 off_linktype = 24;
995 off_nl = 32; /* 802.11+802.2+SNAP */
996 off_nl_nosnap = 27; /* 802.11+802.2 */
997 return;
998
999 case DLT_ATM_RFC1483:
1000 case DLT_ATM_CLIP: /* Linux ATM defines this */
1001 /*
1002 * assume routed, non-ISO PDUs
1003 * (i.e., LLC = 0xAA-AA-03, OUT = 0x00-00-00)
1004 *
1005 * XXX - what about ISO PDUs, e.g. CLNP, ISIS, ESIS,
1006 * or PPP with the PPP NLPID (e.g., PPPoA)? The
1007 * latter would presumably be treated the way PPPoE
1008 * should be, so you can do "pppoe and udp port 2049"
1009 * or "pppoa and tcp port 80" and have it check for
1010 * PPPo{A,E} and a PPP protocol of IP and....
1011 */
1012 off_linktype = 0;
1013 off_nl = 8; /* 802.2+SNAP */
1014 off_nl_nosnap = 3; /* 802.2 */
1015 return;
1016
1017 case DLT_SUNATM:
1018 /*
--- 58 unchanged lines hidden (view full) ---
1077 off_linktype = -1;
1078 off_nl = 0;
1079 off_nl_nosnap = 0; /* no 802.2 LLC */
1080 return;
1081
1082 case DLT_APPLE_IP_OVER_IEEE1394:
1083 off_linktype = 16;
1084 off_nl = 18;
1085 off_nl_nosnap = 18; /* no 802.2 LLC */
1086 return;
1087
1088 case DLT_LINUX_IRDA:
1089 /*
1090 * Currently, only raw "link[N:M]" filtering is supported.
1091 */
1092 off_linktype = -1;
1093 off_nl = -1;
--- 12 unchanged lines hidden (view full) ---
1106 case DLT_SYMANTEC_FIREWALL:
1107 off_linktype = 6;
1108 off_nl = 44; /* Ethernet II */
1109 off_nl_nosnap = 44; /* XXX - what does it do with 802.3 packets? */
1110 return;
1111
1112 case DLT_PFLOG:
1113 off_linktype = 0;
1114 /* XXX read this from pf.h? */
1115 off_nl = PFLOG_HDRLEN;
1116 off_nl_nosnap = PFLOG_HDRLEN; /* no 802.2 LLC */
1117 return;
1118
1119 case DLT_JUNIPER_MLFR:
1120 case DLT_JUNIPER_MLPPP:
1121 off_linktype = 4;
1122 off_nl = 4;
1123 off_nl_nosnap = -1; /* no 802.2 LLC */
1124 return;
1125
1126 case DLT_JUNIPER_ATM1:
1127 off_linktype = 4; /* in reality variable between 4-8 */
1128 off_nl = 4;
1129 off_nl_nosnap = 14;
1130 return;
1131
1132 case DLT_JUNIPER_ATM2:
1133 off_linktype = 8; /* in reality variable between 8-12 */
1134 off_nl = 8;
1135 off_nl_nosnap = 18;
1136 return;
1137
1138 /* frames captured on a Juniper PPPoE service PIC
1139 * contain raw ethernet frames */
1140 case DLT_JUNIPER_PPPOE:
1141 off_linktype = 16;
1142 off_nl = 18; /* Ethernet II */
1143 off_nl_nosnap = 21; /* 802.3+802.2 */
1144 return;
1145
1146 case DLT_JUNIPER_PPPOE_ATM:
1147 off_linktype = 4;
1148 off_nl = 6;
1149 off_nl_nosnap = -1; /* no 802.2 LLC */
1150 return;
1151
1152 case DLT_JUNIPER_GGSN:
1153 off_linktype = 6;
1154 off_nl = 12;
1155 off_nl_nosnap = -1; /* no 802.2 LLC */
1156 return;
1157
1158 case DLT_JUNIPER_ES:
1159 off_linktype = 6;
1160 off_nl = -1; /* not really a network layer but raw IP adresses */
1161 off_nl_nosnap = -1; /* no 802.2 LLC */
1162 return;
1163
1164 case DLT_JUNIPER_MONITOR:
1165 off_linktype = 12;
1166 off_nl = 12; /* raw IP/IP6 header */
1167 off_nl_nosnap = -1; /* no 802.2 LLC */
1168 return;
1169
1170 case DLT_JUNIPER_SERVICES:
1171 off_linktype = 12;
1172 off_nl = -1; /* L3 proto location dep. on cookie type */
1173 off_nl_nosnap = -1; /* no 802.2 LLC */
1174 return;
1175
1176 case DLT_MTP2:
1177 off_sio = 3;
1178 off_opc = 4;
1179 off_dpc = 4;
1180 off_sls = 7;
1181 off_linktype = -1;
1182 off_nl = -1;
1183 off_nl_nosnap = -1;
1184 return;
1185
1186#ifdef DLT_PFSYNC
1187 case DLT_PFSYNC:
1188 off_linktype = -1;
1189 off_nl = 4;
1190 off_nl_nosnap = 4;
1191 return;
1192#endif
1193
1194 case DLT_LINUX_LAPD:
1195 /*
1196 * Currently, only raw "link[N:M]" filtering is supported.
1197 */
1198 off_linktype = -1;
1199 off_nl = -1;
1200 off_nl_nosnap = -1;
1201 return;
1202 }
1203 bpf_error("unknown data link type %d", linktype);
1204 /* NOTREACHED */
1205}
1206
1207/*
1208 * Load a value relative to the beginning of the link-layer header.
1209 * The link-layer header doesn't necessarily begin at the beginning
1210 * of the packet data; there might be a variable-length prefix containing
1211 * radio information.
1212 */
1213static struct slist *
1214gen_load_llrel(offset, size)
1215 u_int offset, size;
1216{
1217 struct slist *s, *s2;
1218
1219 s = gen_llprefixlen();
1220
1221 /*
1222 * If "s" is non-null, it has code to arrange that the X register
1223 * contains the length of the prefix preceding the link-layer
1224 * header.
1225 */
1226 if (s != NULL) {
1227 s2 = new_stmt(BPF_LD|BPF_IND|size);
1228 s2->s.k = offset;
1229 sappend(s, s2);
1230 } else {
1231 s = new_stmt(BPF_LD|BPF_ABS|size);
1232 s->s.k = offset;
1233 }
1234 return s;
1235}
1236
1237/*
1238 * Load a value relative to the beginning of the specified header.
1239 */
1240static struct slist *
1241gen_load_a(offrel, offset, size)
1242 enum e_offrel offrel;
1243 u_int offset, size;
1244{
1245 struct slist *s, *s2;
1246
1247 switch (offrel) {
1248
1249 case OR_PACKET:
1250 s = gen_load_llrel(offset, size);
1251 break;
1252
1253 case OR_LINK:
1254 s = gen_load_llrel(off_ll + offset, size);
1255 break;
1256
1257 case OR_NET:
1258 s = gen_load_llrel(off_nl + offset, size);
1259 break;
1260
1261 case OR_NET_NOSNAP:
1262 s = gen_load_llrel(off_nl_nosnap + offset, size);
1263 break;
1264
1265 case OR_TRAN_IPV4:
1266 /*
1267 * Load the X register with the length of the IPv4 header,
1268 * in bytes.
1269 */
1270 s = gen_loadx_iphdrlen();
1271
1272 /*
1273 * Load the item at {length of the link-layer header} +
1274 * {length of the IPv4 header} + {specified offset}.
1275 */
1276 s2 = new_stmt(BPF_LD|BPF_IND|size);
1277 s2->s.k = off_nl + offset;
1278 sappend(s, s2);
1279 break;
1280
1281 case OR_TRAN_IPV6:
1282 s = gen_load_llrel(off_nl + 40 + offset, size);
1283 break;
1284
1285 default:
1286 abort();
1287 return NULL;
1288 }
1289 return s;
1290}
1291
1292/*
1293 * Generate code to load into the X register the sum of the length of
1294 * the IPv4 header and any variable-length header preceding the link-layer
1295 * header.
1296 */
1297static struct slist *
1298gen_loadx_iphdrlen()
1299{
1300 struct slist *s, *s2;
1301
1302 s = gen_llprefixlen();
1303 if (s != NULL) {
1304 /*
1305 * There's a variable-length prefix preceding the
1306 * link-layer header. "s" points to a list of statements
1307 * that put the length of that prefix into the X register.
1308 * The 4*([k]&0xf) addressing mode can't be used, as we
1309 * don't have a constant offset, so we have to load the
1310 * value in question into the A register and add to it
1311 * the value from the X register.
1312 */
1313 s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
1314 s2->s.k = off_nl;
1315 sappend(s, s2);
1316 s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
1317 s2->s.k = 0xf;
1318 sappend(s, s2);
1319 s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
1320 s2->s.k = 2;
1321 sappend(s, s2);
1322
1323 /*
1324 * The A register now contains the length of the
1325 * IP header. We need to add to it the length
1326 * of the prefix preceding the link-layer
1327 * header, which is still in the X register, and
1328 * move the result into the X register.
1329 */
1330 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
1331 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
1332 } else {
1333 /*
1334 * There is no variable-length header preceding the
1335 * link-layer header; if there's a fixed-length
1336 * header preceding it, its length is included in
1337 * the off_ variables, so it doesn't need to be added.
1338 */
1339 s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
1340 s->s.k = off_nl;
1341 }
1342 return s;
1343}
1344
1345static struct block *
1346gen_uncond(rsense)
1347 int rsense;
1348{
1349 struct block *b;
1350 struct slist *s;
1351
1352 s = new_stmt(BPF_LD|BPF_IMM);
--- 19 unchanged lines hidden (view full) ---
1372/*
1373 * Byte-swap a 32-bit number.
1374 * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
1375 * big-endian platforms.)
1376 */
1377#define SWAPLONG(y) \
1378((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
1379
1380/*
1381 * Generate code to match a particular packet type.
1382 *
1383 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
1384 * value, if <= ETHERMTU. We use that to determine whether to
1385 * match the type/length field or to check the type/length field for
1386 * a value <= ETHERMTU to see whether it's a type field and then do
1387 * the appropriate test.
1388 */
1389static struct block *
1390gen_ether_linktype(proto)
1391 register int proto;
1392{
1393 struct block *b0, *b1;
1394
1395 switch (proto) {
1396
1397 case LLCSAP_ISONS:
1398 case LLCSAP_IP:
1399 case LLCSAP_NETBEUI:
1400 /*
1401 * OSI protocols and NetBEUI always use 802.2 encapsulation,
1402 * so we check the DSAP and SSAP.
1403 *
1404 * LLCSAP_IP checks for IP-over-802.2, rather
1405 * than IP-over-Ethernet or IP-over-SNAP.
1406 *
1407 * XXX - should we check both the DSAP and the
1408 * SSAP, like this, or should we check just the
1409 * DSAP, as we do for other types <= ETHERMTU
1410 * (i.e., other SAP values)?
1411 */
1412 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1413 gen_not(b0);
1414 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H, (bpf_int32)
1415 ((proto << 8) | proto));
1416 gen_and(b0, b1);
1417 return b1;
1418
1419 case LLCSAP_IPX:
1420 /*
1421 * Check for;
1422 *
1423 * Ethernet_II frames, which are Ethernet
--- 20 unchanged lines hidden (view full) ---
1444 * XXX - should we generate the same code both
1445 * for tests for LLCSAP_IPX and for ETHERTYPE_IPX?
1446 */
1447
1448 /*
1449 * This generates code to check both for the
1450 * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3.
1451 */
1452 b0 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1453 (bpf_int32)LLCSAP_IPX);
1454 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H,
1455 (bpf_int32)0xFFFF);
1456 gen_or(b0, b1);
1457
1458 /*
1459 * Now we add code to check for SNAP frames with
1460 * ETHERTYPE_IPX, i.e. Ethernet_SNAP.
1461 */
1462 b0 = gen_snap(0x000000, ETHERTYPE_IPX, 14);
1463 gen_or(b0, b1);
1464
1465 /*
1466 * Now we generate code to check for 802.3
1467 * frames in general.
1468 */
1469 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1470 gen_not(b0);
1471
1472 /*
1473 * Now add the check for 802.3 frames before the
1474 * check for Ethernet_802.2 and Ethernet_802.3,
1475 * as those checks should only be done on 802.3
1476 * frames, not on Ethernet frames.
1477 */
1478 gen_and(b0, b1);
1479
1480 /*
1481 * Now add the check for Ethernet_II frames, and
1482 * do that before checking for the other frame
1483 * types.
1484 */
1485 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1486 (bpf_int32)ETHERTYPE_IPX);
1487 gen_or(b0, b1);
1488 return b1;
1489
1490 case ETHERTYPE_ATALK:
1491 case ETHERTYPE_AARP:
1492 /*
1493 * EtherTalk (AppleTalk protocols on Ethernet link
1494 * layer) may use 802.2 encapsulation.
1495 */
1496
1497 /*
1498 * Check for 802.2 encapsulation (EtherTalk phase 2?);
1499 * we check for an Ethernet type field less than
1500 * 1500, which means it's an 802.3 length field.
1501 */
1502 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1503 gen_not(b0);
1504
1505 /*
1506 * 802.2-encapsulated ETHERTYPE_ATALK packets are
1507 * SNAP packets with an organization code of
1508 * 0x080007 (Apple, for Appletalk) and a protocol
1509 * type of ETHERTYPE_ATALK (Appletalk).
1510 *
--- 8 unchanged lines hidden (view full) ---
1519 b1 = gen_snap(0x000000, ETHERTYPE_AARP, 14);
1520 gen_and(b0, b1);
1521
1522 /*
1523 * Check for Ethernet encapsulation (Ethertalk
1524 * phase 1?); we just check for the Ethernet
1525 * protocol type.
1526 */
1527 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
1528
1529 gen_or(b0, b1);
1530 return b1;
1531
1532 default:
1533 if (proto <= ETHERMTU) {
1534 /*
1535 * This is an LLC SAP value, so the frames
1536 * that match would be 802.2 frames.
1537 * Check that the frame is an 802.2 frame
1538 * (i.e., that the length/type field is
1539 * a length field, <= ETHERMTU) and
1540 * then check the DSAP.
1541 */
1542 b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
1543 gen_not(b0);
1544 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1545 (bpf_int32)proto);
1546 gen_and(b0, b1);
1547 return b1;
1548 } else {
1549 /*
1550 * This is an Ethernet type, so compare
1551 * the length/type field with it (if
1552 * the frame is an 802.2 frame, the length
1553 * field will be <= ETHERMTU, and, as
1554 * "proto" is > ETHERMTU, this test
1555 * will fail and the frame won't match,
1556 * which is what we want).
1557 */
1558 return gen_cmp(OR_LINK, off_linktype, BPF_H,
1559 (bpf_int32)proto);
1560 }
1561 }
1562}
1563
1564/*
1565 * Generate code to match a particular packet type.
1566 *
1567 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
1568 * value, if <= ETHERMTU. We use that to determine whether to
1569 * match the type field or to check the type field for the special
1570 * LINUX_SLL_P_802_2 value and then do the appropriate test.
1571 */
1572static struct block *
1573gen_linux_sll_linktype(proto)
1574 register int proto;
1575{
1576 struct block *b0, *b1;
1577
1578 switch (proto) {
1579
1580 case LLCSAP_ISONS:
1581 case LLCSAP_IP:
1582 case LLCSAP_NETBEUI:
1583 /*
1584 * OSI protocols and NetBEUI always use 802.2 encapsulation,
1585 * so we check the DSAP and SSAP.
1586 *
1587 * LLCSAP_IP checks for IP-over-802.2, rather
1588 * than IP-over-Ethernet or IP-over-SNAP.
1589 *
1590 * XXX - should we check both the DSAP and the
1591 * SSAP, like this, or should we check just the
1592 * DSAP, as we do for other types <= ETHERMTU
1593 * (i.e., other SAP values)?
1594 */
1595 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
1596 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H, (bpf_int32)
1597 ((proto << 8) | proto));
1598 gen_and(b0, b1);
1599 return b1;
1600
1601 case LLCSAP_IPX:
1602 /*
1603 * Ethernet_II frames, which are Ethernet
1604 * frames with a frame type of ETHERTYPE_IPX;
1605 *
1606 * Ethernet_802.3 frames, which have a frame
1607 * type of LINUX_SLL_P_802_3;
1608 *
--- 10 unchanged lines hidden (view full) ---
1619 * ID of ETHERTYPE_IPX in the SNAP header.
1620 *
1621 * First, do the checks on LINUX_SLL_P_802_2
1622 * frames; generate the check for either
1623 * Ethernet_802.2 or Ethernet_SNAP frames, and
1624 * then put a check for LINUX_SLL_P_802_2 frames
1625 * before it.
1626 */
1627 b0 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1628 (bpf_int32)LLCSAP_IPX);
1629 b1 = gen_snap(0x000000, ETHERTYPE_IPX,
1630 off_linktype + 2);
1631 gen_or(b0, b1);
1632 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
1633 gen_and(b0, b1);
1634
1635 /*
1636 * Now check for 802.3 frames and OR that with
1637 * the previous test.
1638 */
1639 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_3);
1640 gen_or(b0, b1);
1641
1642 /*
1643 * Now add the check for Ethernet_II frames, and
1644 * do that before checking for the other frame
1645 * types.
1646 */
1647 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1648 (bpf_int32)ETHERTYPE_IPX);
1649 gen_or(b0, b1);
1650 return b1;
1651
1652 case ETHERTYPE_ATALK:
1653 case ETHERTYPE_AARP:
1654 /*
1655 * EtherTalk (AppleTalk protocols on Ethernet link
1656 * layer) may use 802.2 encapsulation.
1657 */
1658
1659 /*
1660 * Check for 802.2 encapsulation (EtherTalk phase 2?);
1661 * we check for the 802.2 protocol type in the
1662 * "Ethernet type" field.
1663 */
1664 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
1665
1666 /*
1667 * 802.2-encapsulated ETHERTYPE_ATALK packets are
1668 * SNAP packets with an organization code of
1669 * 0x080007 (Apple, for Appletalk) and a protocol
1670 * type of ETHERTYPE_ATALK (Appletalk).
1671 *
1672 * 802.2-encapsulated ETHERTYPE_AARP packets are
--- 9 unchanged lines hidden (view full) ---
1682 off_linktype + 2);
1683 gen_and(b0, b1);
1684
1685 /*
1686 * Check for Ethernet encapsulation (Ethertalk
1687 * phase 1?); we just check for the Ethernet
1688 * protocol type.
1689 */
1690 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
1691
1692 gen_or(b0, b1);
1693 return b1;
1694
1695 default:
1696 if (proto <= ETHERMTU) {
1697 /*
1698 * This is an LLC SAP value, so the frames
1699 * that match would be 802.2 frames.
1700 * Check for the 802.2 protocol type
1701 * in the "Ethernet type" field, and
1702 * then check the DSAP.
1703 */
1704 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
1705 LINUX_SLL_P_802_2);
1706 b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
1707 (bpf_int32)proto);
1708 gen_and(b0, b1);
1709 return b1;
1710 } else {
1711 /*
1712 * This is an Ethernet type, so compare
1713 * the length/type field with it (if
1714 * the frame is an 802.2 frame, the length
1715 * field will be <= ETHERMTU, and, as
1716 * "proto" is > ETHERMTU, this test
1717 * will fail and the frame won't match,
1718 * which is what we want).
1719 */
1720 return gen_cmp(OR_LINK, off_linktype, BPF_H,
1721 (bpf_int32)proto);
1722 }
1723 }
1724}
1725
1726static void
1727insert_radiotap_load_llprefixlen(b)
1728 struct block *b;
1729{
1730 struct slist *s1, *s2;
1731
1732 /*
1733 * Prepend to the statements in this block code to load the
1734 * length of the radiotap header into the register assigned
1735 * to hold that length, if one has been assigned.
1736 */
1737 if (reg_ll_size != -1) {
1738 /*
1739 * The 2 bytes at offsets of 2 and 3 from the beginning
1740 * of the radiotap header are the length of the radiotap
1741 * header; unfortunately, it's little-endian, so we have
1742 * to load it a byte at a time and construct the value.
1743 */
1744
1745 /*
1746 * Load the high-order byte, at an offset of 3, shift it
1747 * left a byte, and put the result in the X register.
1748 */
1749 s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
1750 s1->s.k = 3;
1751 s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
1752 sappend(s1, s2);
1753 s2->s.k = 8;
1754 s2 = new_stmt(BPF_MISC|BPF_TAX);
1755 sappend(s1, s2);
1756
1757 /*
1758 * Load the next byte, at an offset of 2, and OR the
1759 * value from the X register into it.
1760 */
1761 s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
1762 sappend(s1, s2);
1763 s2->s.k = 2;
1764 s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
1765 sappend(s1, s2);
1766
1767 /*
1768 * Now allocate a register to hold that value and store
1769 * it.
1770 */
1771 s2 = new_stmt(BPF_ST);
1772 s2->s.k = reg_ll_size;
1773 sappend(s1, s2);
1774
1775 /*
1776 * Now move it into the X register.
1777 */
1778 s2 = new_stmt(BPF_MISC|BPF_TAX);
1779 sappend(s1, s2);
1780
1781 /*
1782 * Now append all the existing statements in this
1783 * block to these statements.
1784 */
1785 sappend(s1, b->stmts);
1786 b->stmts = s1;
1787 }
1788}
1789
1790
1791static void
1792insert_load_llprefixlen(b)
1793 struct block *b;
1794{
1795 switch (linktype) {
1796
1797 case DLT_IEEE802_11_RADIO:
1798 insert_radiotap_load_llprefixlen(b);
1799 }
1800}
1801
1802
1803static struct slist *
1804gen_radiotap_llprefixlen(void)
1805{
1806 struct slist *s;
1807
1808 if (reg_ll_size == -1) {
1809 /*
1810 * We haven't yet assigned a register for the length
1811 * of the radiotap header; allocate one.
1812 */
1813 reg_ll_size = alloc_reg();
1814 }
1815
1816 /*
1817 * Load the register containing the radiotap length
1818 * into the X register.
1819 */
1820 s = new_stmt(BPF_LDX|BPF_MEM);
1821 s->s.k = reg_ll_size;
1822 return s;
1823}
1824
1825/*
1826 * Generate code to compute the link-layer header length, if necessary,
1827 * putting it into the X register, and to return either a pointer to a
1828 * "struct slist" for the list of statements in that code, or NULL if
1829 * no code is necessary.
1830 */
1831static struct slist *
1832gen_llprefixlen(void)
1833{
1834 switch (linktype) {
1835
1836 case DLT_IEEE802_11_RADIO:
1837 return gen_radiotap_llprefixlen();
1838
1839 default:
1840 return NULL;
1841 }
1842}
1843
1844/*
1845 * Generate code to match a particular packet type by matching the
1846 * link-layer type field or fields in the 802.2 LLC header.
1847 *
1848 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
1849 * value, if <= ETHERMTU.
1850 */
1851static struct block *
1852gen_linktype(proto)
1853 register int proto;
1854{
1855 struct block *b0, *b1, *b2;
1856
1857 switch (linktype) {
1858
--- 5 unchanged lines hidden (view full) ---
1864 case DLT_C_HDLC:
1865 switch (proto) {
1866
1867 case LLCSAP_ISONS:
1868 proto = (proto << 8 | LLCSAP_ISONS);
1869 /* fall through */
1870
1871 default:
1872 return gen_cmp(OR_LINK, off_linktype, BPF_H,
1873 (bpf_int32)proto);
1874 /*NOTREACHED*/
1875 break;
1876 }
1877 break;
1878
1879 case DLT_FDDI:
1880 case DLT_IEEE802:
1881 case DLT_IEEE802_11:
1882 case DLT_IEEE802_11_RADIO_AVS:
1883 case DLT_IEEE802_11_RADIO:
1884 case DLT_PRISM_HEADER:
1885 case DLT_ATM_RFC1483:
1886 case DLT_ATM_CLIP:
1887 case DLT_IP_OVER_FC:
1888 return gen_llc_linktype(proto);
1889 /*NOTREACHED*/
1890 break;
1891
1892 case DLT_SUNATM:
1893 /*
1894 * If "is_lane" is set, check for a LANE-encapsulated
1895 * version of this protocol, otherwise check for an
1896 * LLC-encapsulated version of this protocol.
1897 *
1898 * We assume LANE means Ethernet, not Token Ring.
1899 */
1900 if (is_lane) {
1901 /*
1902 * Check that the packet doesn't begin with an
1903 * LE Control marker. (We've already generated
1904 * a test for LANE.)
1905 */
1906 b0 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
1907 0xFF00);
1908 gen_not(b0);
1909
1910 /*
1911 * Now generate an Ethernet test.
1912 */
1913 b1 = gen_ether_linktype(proto);
1914 gen_and(b0, b1);
1915 return b1;
1916 } else {
1917 /*
1918 * Check for LLC encapsulation and then check the
1919 * protocol.
1920 */
1921 b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
1922 b1 = gen_llc_linktype(proto);
1923 gen_and(b0, b1);
1924 return b1;
1925 }
1926 /*NOTREACHED*/
1927 break;
1928
1929 case DLT_LINUX_SLL:
1930 return gen_linux_sll_linktype(proto);
1931 /*NOTREACHED*/
1932 break;
1933
1934 case DLT_SLIP:
1935 case DLT_SLIP_BSDOS:
--- 73 unchanged lines hidden (view full) ---
2009 case DLT_PPP_BSDOS:
2010 /*
2011 * We use Ethernet protocol types inside libpcap;
2012 * map them to the corresponding PPP protocol types.
2013 */
2014 switch (proto) {
2015
2016 case ETHERTYPE_IP:
2017 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_IP);
2018 b1 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJC);
2019 gen_or(b0, b1);
2020 b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJNC);
2021 gen_or(b1, b0);
2022 return b0;
2023
2024#ifdef INET6
2025 case ETHERTYPE_IPV6:
2026 proto = PPP_IPV6;
2027 /* more to go? */
2028 break;
--- 89 unchanged lines hidden (view full) ---
2118 * Then we run it through "htonl()", and
2119 * generate code to compare against the result.
2120 */
2121 if (bpf_pcap->sf.rfile != NULL &&
2122 bpf_pcap->sf.swapped)
2123 proto = SWAPLONG(proto);
2124 proto = htonl(proto);
2125 }
2126 return (gen_cmp(OR_LINK, 0, BPF_W, (bpf_int32)proto));
2127
2128 case DLT_PFLOG:
2129 /*
2130 * af field is host byte order in contrast to the rest of
2131 * the packet.
2132 */
2133 if (proto == ETHERTYPE_IP)
2134 return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
2135 BPF_B, (bpf_int32)AF_INET));
2136#ifdef INET6
2137 else if (proto == ETHERTYPE_IPV6)
2138 return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
2139 BPF_B, (bpf_int32)AF_INET6));
2140#endif /* INET6 */
2141 else
2142 return gen_false();
2143 /*NOTREACHED*/
2144 break;
2145
2146 case DLT_ARCNET:
2147 case DLT_ARCNET_LINUX:
2148 /*
2149 * XXX should we check for first fragment if the protocol
2150 * uses PHDS?
2151 */
2152 switch (proto) {
2153
2154 default:
2155 return gen_false();
2156
2157#ifdef INET6
2158 case ETHERTYPE_IPV6:
2159 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
2160 (bpf_int32)ARCTYPE_INET6));
2161#endif /* INET6 */
2162
2163 case ETHERTYPE_IP:
2164 b0 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2165 (bpf_int32)ARCTYPE_IP);
2166 b1 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2167 (bpf_int32)ARCTYPE_IP_OLD);
2168 gen_or(b0, b1);
2169 return (b1);
2170
2171 case ETHERTYPE_ARP:
2172 b0 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2173 (bpf_int32)ARCTYPE_ARP);
2174 b1 = gen_cmp(OR_LINK, off_linktype, BPF_B,
2175 (bpf_int32)ARCTYPE_ARP_OLD);
2176 gen_or(b0, b1);
2177 return (b1);
2178
2179 case ETHERTYPE_REVARP:
2180 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
2181 (bpf_int32)ARCTYPE_REVARP));
2182
2183 case ETHERTYPE_ATALK:
2184 return (gen_cmp(OR_LINK, off_linktype, BPF_B,
2185 (bpf_int32)ARCTYPE_ATALK));
2186 }
2187 /*NOTREACHED*/
2188 break;
2189
2190 case DLT_LTALK:
2191 switch (proto) {
2192 case ETHERTYPE_ATALK:
--- 10 unchanged lines hidden (view full) ---
2203 * DLCI and flags. What if the address is longer?
2204 */
2205 switch (proto) {
2206
2207 case ETHERTYPE_IP:
2208 /*
2209 * Check for the special NLPID for IP.
2210 */
2211 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0xcc);
2212
2213#ifdef INET6
2214 case ETHERTYPE_IPV6:
2215 /*
2216 * Check for the special NLPID for IPv6.
2217 */
2218 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0x8e);
2219#endif
2220
2221 case LLCSAP_ISONS:
2222 /*
2223 * Check for several OSI protocols.
2224 *
2225 * Frame Relay packets typically have an OSI
2226 * NLPID at the beginning; we check for each
2227 * of them.
2228 *
2229 * What we check for is the NLPID and a frame
2230 * control field of UI, i.e. 0x03 followed
2231 * by the NLPID.
2232 */
2233 b0 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO8473_CLNP);
2234 b1 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO9542_ESIS);
2235 b2 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO10589_ISIS);
2236 gen_or(b1, b2);
2237 gen_or(b0, b2);
2238 return b2;
2239
2240 default:
2241 return gen_false();
2242 }
2243 /*NOTREACHED*/
2244 break;
2245
2246 case DLT_JUNIPER_MLFR:
2247 case DLT_JUNIPER_MLPPP:
2248 case DLT_JUNIPER_ATM1:
2249 case DLT_JUNIPER_ATM2:
2250 case DLT_JUNIPER_PPPOE:
2251 case DLT_JUNIPER_PPPOE_ATM:
2252 case DLT_JUNIPER_GGSN:
2253 case DLT_JUNIPER_ES:
2254 case DLT_JUNIPER_MONITOR:
2255 case DLT_JUNIPER_SERVICES:
2256 /* just lets verify the magic number for now -
2257 * on ATM we may have up to 6 different encapsulations on the wire
2258 * and need a lot of heuristics to figure out that the payload
2259 * might be;
2260 *
2261 * FIXME encapsulation specific BPF_ filters
2262 */
2263 return gen_mcmp(OR_LINK, 0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */
2264
2265 case DLT_LINUX_IRDA:
2266 bpf_error("IrDA link-layer type filtering not implemented");
2267
2268 case DLT_DOCSIS:
2269 bpf_error("DOCSIS link-layer type filtering not implemented");
2270
2271 case DLT_LINUX_LAPD:
2272 bpf_error("LAPD link-layer type filtering not implemented");
2273 }
2274
2275 /*
2276 * All the types that have no encapsulation should either be
2277 * handled as DLT_SLIP, DLT_SLIP_BSDOS, and DLT_RAW are, if
2278 * all packets are IP packets, or should be handled in some
2279 * special case, if none of them are (if some are and some
2280 * aren't, the lack of encapsulation is a problem, as we'd
--- 8 unchanged lines hidden (view full) ---
2289 * Any type not handled above should always have an Ethernet
2290 * type at an offset of "off_linktype". (PPP is partially
2291 * handled above - the protocol type is mapped from the
2292 * Ethernet and LLC types we use internally to the corresponding
2293 * PPP type - but the PPP type is always specified by a value
2294 * at "off_linktype", so we don't have to do the code generation
2295 * above.)
2296 */
2297 return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
2298}
2299
2300/*
2301 * Check for an LLC SNAP packet with a given organization code and
2302 * protocol type; we check the entire contents of the 802.2 LLC and
2303 * snap headers, checking for DSAP and SSAP of SNAP and a control
2304 * field of 0x03 in the LLC header, and for the specified organization
2305 * code and protocol type in the SNAP header.
--- 9 unchanged lines hidden (view full) ---
2315 snapblock[0] = LLCSAP_SNAP; /* DSAP = SNAP */
2316 snapblock[1] = LLCSAP_SNAP; /* SSAP = SNAP */
2317 snapblock[2] = 0x03; /* control = UI */
2318 snapblock[3] = (orgcode >> 16); /* upper 8 bits of organization code */
2319 snapblock[4] = (orgcode >> 8); /* middle 8 bits of organization code */
2320 snapblock[5] = (orgcode >> 0); /* lower 8 bits of organization code */
2321 snapblock[6] = (ptype >> 8); /* upper 8 bits of protocol type */
2322 snapblock[7] = (ptype >> 0); /* lower 8 bits of protocol type */
2323 return gen_bcmp(OR_LINK, offset, 8, snapblock);
2324}
2325
2326/*
2327 * Generate code to match a particular packet type, for link-layer types
2328 * using 802.2 LLC headers.
2329 *
2330 * This is *NOT* used for Ethernet; "gen_ether_linktype()" is used
2331 * for that - it handles the D/I/X Ethernet vs. 802.3+802.2 issues.
2332 *
2333 * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
2334 * value, if <= ETHERMTU. We use that to determine whether to
2335 * match the DSAP or both DSAP and LSAP or to check the OUI and
2336 * protocol ID in a SNAP header.
2337 */
2338static struct block *
2339gen_llc_linktype(proto)
2340 int proto;
2341{
2342 /*
2343 * XXX - handle token-ring variable-length header.
2344 */
2345 switch (proto) {
2346
2347 case LLCSAP_IP:
2348 case LLCSAP_ISONS:
2349 case LLCSAP_NETBEUI:
2350 /*
2351 * XXX - should we check both the DSAP and the
2352 * SSAP, like this, or should we check just the
2353 * DSAP, as we do for other types <= ETHERMTU
2354 * (i.e., other SAP values)?
2355 */
2356 return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_u_int32)
2357 ((proto << 8) | proto));
2358
2359 case LLCSAP_IPX:
2360 /*
2361 * XXX - are there ever SNAP frames for IPX on
2362 * non-Ethernet 802.x networks?
2363 */
2364 return gen_cmp(OR_LINK, off_linktype, BPF_B,
2365 (bpf_int32)LLCSAP_IPX);
2366
2367 case ETHERTYPE_ATALK:
2368 /*
2369 * 802.2-encapsulated ETHERTYPE_ATALK packets are
2370 * SNAP packets with an organization code of
2371 * 0x080007 (Apple, for Appletalk) and a protocol
2372 * type of ETHERTYPE_ATALK (Appletalk).
2373 *
--- 7 unchanged lines hidden (view full) ---
2381 * XXX - we don't have to check for IPX 802.3
2382 * here, but should we check for the IPX Ethertype?
2383 */
2384 if (proto <= ETHERMTU) {
2385 /*
2386 * This is an LLC SAP value, so check
2387 * the DSAP.
2388 */
2389 return gen_cmp(OR_LINK, off_linktype, BPF_B,
2390 (bpf_int32)proto);
2391 } else {
2392 /*
2393 * This is an Ethernet type; we assume that it's
2394 * unlikely that it'll appear in the right place
2395 * at random, and therefore check only the
2396 * location that would hold the Ethernet type
2397 * in a SNAP frame with an organization code of
2398 * 0x000000 (encapsulated Ethernet).
--- 5 unchanged lines hidden (view full) ---
2404 *
2405 * return gen_snap(0x000000, proto,
2406 * off_linktype);
2407 *
2408 * here; for now, we don't, as per the above.
2409 * I don't know whether it's worth the extra CPU
2410 * time to do the right check or not.
2411 */
2412 return gen_cmp(OR_LINK, off_linktype+6, BPF_H,
2413 (bpf_int32)proto);
2414 }
2415 }
2416}
2417
2418static struct block *
2419gen_hostop(addr, mask, dir, proto, src_off, dst_off)
2420 bpf_u_int32 addr;
2421 bpf_u_int32 mask;
--- 25 unchanged lines hidden (view full) ---
2447 b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
2448 gen_or(b0, b1);
2449 return b1;
2450
2451 default:
2452 abort();
2453 }
2454 b0 = gen_linktype(proto);
2455 b1 = gen_mcmp(OR_NET, offset, BPF_W, (bpf_int32)addr, mask);
2456 gen_and(b0, b1);
2457 return b1;
2458}
2459
2460#ifdef INET6
2461static struct block *
2462gen_hostop6(addr, mask, dir, proto, src_off, dst_off)
2463 struct in6_addr *addr;
--- 29 unchanged lines hidden (view full) ---
2493 return b1;
2494
2495 default:
2496 abort();
2497 }
2498 /* this order is important */
2499 a = (u_int32_t *)addr;
2500 m = (u_int32_t *)mask;
2501 b1 = gen_mcmp(OR_NET, offset + 12, BPF_W, ntohl(a[3]), ntohl(m[3]));
2502 b0 = gen_mcmp(OR_NET, offset + 8, BPF_W, ntohl(a[2]), ntohl(m[2]));
2503 gen_and(b0, b1);
2504 b0 = gen_mcmp(OR_NET, offset + 4, BPF_W, ntohl(a[1]), ntohl(m[1]));
2505 gen_and(b0, b1);
2506 b0 = gen_mcmp(OR_NET, offset + 0, BPF_W, ntohl(a[0]), ntohl(m[0]));
2507 gen_and(b0, b1);
2508 b0 = gen_linktype(proto);
2509 gen_and(b0, b1);
2510 return b1;
2511}
2512#endif /*INET6*/
2513
2514static struct block *
2515gen_ehostop(eaddr, dir)
2516 register const u_char *eaddr;
2517 register int dir;
2518{
2519 register struct block *b0, *b1;
2520
2521 switch (dir) {
2522 case Q_SRC:
2523 return gen_bcmp(OR_LINK, off_mac + 6, 6, eaddr);
2524
2525 case Q_DST:
2526 return gen_bcmp(OR_LINK, off_mac + 0, 6, eaddr);
2527
2528 case Q_AND:
2529 b0 = gen_ehostop(eaddr, Q_SRC);
2530 b1 = gen_ehostop(eaddr, Q_DST);
2531 gen_and(b0, b1);
2532 return b1;
2533
2534 case Q_DEFAULT:
--- 15 unchanged lines hidden (view full) ---
2550 register const u_char *eaddr;
2551 register int dir;
2552{
2553 struct block *b0, *b1;
2554
2555 switch (dir) {
2556 case Q_SRC:
2557#ifdef PCAP_FDDIPAD
2558 return gen_bcmp(OR_LINK, 6 + 1 + pcap_fddipad, 6, eaddr);
2559#else
2560 return gen_bcmp(OR_LINK, 6 + 1, 6, eaddr);
2561#endif
2562
2563 case Q_DST:
2564#ifdef PCAP_FDDIPAD
2565 return gen_bcmp(OR_LINK, 0 + 1 + pcap_fddipad, 6, eaddr);
2566#else
2567 return gen_bcmp(OR_LINK, 0 + 1, 6, eaddr);
2568#endif
2569
2570 case Q_AND:
2571 b0 = gen_fhostop(eaddr, Q_SRC);
2572 b1 = gen_fhostop(eaddr, Q_DST);
2573 gen_and(b0, b1);
2574 return b1;
2575
--- 15 unchanged lines hidden (view full) ---
2591gen_thostop(eaddr, dir)
2592 register const u_char *eaddr;
2593 register int dir;
2594{
2595 register struct block *b0, *b1;
2596
2597 switch (dir) {
2598 case Q_SRC:
2599 return gen_bcmp(OR_LINK, 8, 6, eaddr);
2600
2601 case Q_DST:
2602 return gen_bcmp(OR_LINK, 2, 6, eaddr);
2603
2604 case Q_AND:
2605 b0 = gen_thostop(eaddr, Q_SRC);
2606 b1 = gen_thostop(eaddr, Q_DST);
2607 gen_and(b0, b1);
2608 return b1;
2609
2610 case Q_DEFAULT:
--- 40 unchanged lines hidden (view full) ---
2651 */
2652
2653 /*
2654 * Generate the tests to be done for data frames
2655 * with From DS set.
2656 *
2657 * First, check for To DS set, i.e. check "link[1] & 0x01".
2658 */
2659 s = gen_load_a(OR_LINK, 1, BPF_B);
2660 b1 = new_block(JMP(BPF_JSET));
2661 b1->s.k = 0x01; /* To DS */
2662 b1->stmts = s;
2663
2664 /*
2665 * If To DS is set, the SA is at 24.
2666 */
2667 b0 = gen_bcmp(OR_LINK, 24, 6, eaddr);
2668 gen_and(b1, b0);
2669
2670 /*
2671 * Now, check for To DS not set, i.e. check
2672 * "!(link[1] & 0x01)".
2673 */
2674 s = gen_load_a(OR_LINK, 1, BPF_B);
2675 b2 = new_block(JMP(BPF_JSET));
2676 b2->s.k = 0x01; /* To DS */
2677 b2->stmts = s;
2678 gen_not(b2);
2679
2680 /*
2681 * If To DS is not set, the SA is at 16.
2682 */
2683 b1 = gen_bcmp(OR_LINK, 16, 6, eaddr);
2684 gen_and(b2, b1);
2685
2686 /*
2687 * Now OR together the last two checks. That gives
2688 * the complete set of checks for data frames with
2689 * From DS set.
2690 */
2691 gen_or(b1, b0);
2692
2693 /*
2694 * Now check for From DS being set, and AND that with
2695 * the ORed-together checks.
2696 */
2697 s = gen_load_a(OR_LINK, 1, BPF_B);
2698 b1 = new_block(JMP(BPF_JSET));
2699 b1->s.k = 0x02; /* From DS */
2700 b1->stmts = s;
2701 gen_and(b1, b0);
2702
2703 /*
2704 * Now check for data frames with From DS not set.
2705 */
2706 s = gen_load_a(OR_LINK, 1, BPF_B);
2707 b2 = new_block(JMP(BPF_JSET));
2708 b2->s.k = 0x02; /* From DS */
2709 b2->stmts = s;
2710 gen_not(b2);
2711
2712 /*
2713 * If From DS isn't set, the SA is at 10.
2714 */
2715 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
2716 gen_and(b2, b1);
2717
2718 /*
2719 * Now OR together the checks for data frames with
2720 * From DS not set and for data frames with From DS
2721 * set; that gives the checks done for data frames.
2722 */
2723 gen_or(b1, b0);
2724
2725 /*
2726 * Now check for a data frame.
2727 * I.e, check "link[0] & 0x08".
2728 */
2729 gen_load_a(OR_LINK, 0, BPF_B);
2730 b1 = new_block(JMP(BPF_JSET));
2731 b1->s.k = 0x08;
2732 b1->stmts = s;
2733
2734 /*
2735 * AND that with the checks done for data frames.
2736 */
2737 gen_and(b1, b0);
2738
2739 /*
2740 * If the high-order bit of the type value is 0, this
2741 * is a management frame.
2742 * I.e, check "!(link[0] & 0x08)".
2743 */
2744 s = gen_load_a(OR_LINK, 0, BPF_B);
2745 b2 = new_block(JMP(BPF_JSET));
2746 b2->s.k = 0x08;
2747 b2->stmts = s;
2748 gen_not(b2);
2749
2750 /*
2751 * For management frames, the SA is at 10.
2752 */
2753 b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
2754 gen_and(b2, b1);
2755
2756 /*
2757 * OR that with the checks done for data frames.
2758 * That gives the checks done for management and
2759 * data frames.
2760 */
2761 gen_or(b1, b0);
2762
2763 /*
2764 * If the low-order bit of the type value is 1,
2765 * this is either a control frame or a frame
2766 * with a reserved type, and thus not a
2767 * frame with an SA.
2768 *
2769 * I.e., check "!(link[0] & 0x04)".
2770 */
2771 s = gen_load_a(OR_LINK, 0, BPF_B);
2772 b1 = new_block(JMP(BPF_JSET));
2773 b1->s.k = 0x04;
2774 b1->stmts = s;
2775 gen_not(b1);
2776
2777 /*
2778 * AND that with the checks for data and management
2779 * frames.
--- 18 unchanged lines hidden (view full) ---
2798 * if To DS is set.
2799 */
2800
2801 /*
2802 * Generate the tests to be done for data frames.
2803 *
2804 * First, check for To DS set, i.e. "link[1] & 0x01".
2805 */
2806 s = gen_load_a(OR_LINK, 1, BPF_B);
2807 b1 = new_block(JMP(BPF_JSET));
2808 b1->s.k = 0x01; /* To DS */
2809 b1->stmts = s;
2810
2811 /*
2812 * If To DS is set, the DA is at 16.
2813 */
2814 b0 = gen_bcmp(OR_LINK, 16, 6, eaddr);
2815 gen_and(b1, b0);
2816
2817 /*
2818 * Now, check for To DS not set, i.e. check
2819 * "!(link[1] & 0x01)".
2820 */
2821 s = gen_load_a(OR_LINK, 1, BPF_B);
2822 b2 = new_block(JMP(BPF_JSET));
2823 b2->s.k = 0x01; /* To DS */
2824 b2->stmts = s;
2825 gen_not(b2);
2826
2827 /*
2828 * If To DS is not set, the DA is at 4.
2829 */
2830 b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
2831 gen_and(b2, b1);
2832
2833 /*
2834 * Now OR together the last two checks. That gives
2835 * the complete set of checks for data frames.
2836 */
2837 gen_or(b1, b0);
2838
2839 /*
2840 * Now check for a data frame.
2841 * I.e, check "link[0] & 0x08".
2842 */
2843 s = gen_load_a(OR_LINK, 0, BPF_B);
2844 b1 = new_block(JMP(BPF_JSET));
2845 b1->s.k = 0x08;
2846 b1->stmts = s;
2847
2848 /*
2849 * AND that with the checks done for data frames.
2850 */
2851 gen_and(b1, b0);
2852
2853 /*
2854 * If the high-order bit of the type value is 0, this
2855 * is a management frame.
2856 * I.e, check "!(link[0] & 0x08)".
2857 */
2858 s = gen_load_a(OR_LINK, 0, BPF_B);
2859 b2 = new_block(JMP(BPF_JSET));
2860 b2->s.k = 0x08;
2861 b2->stmts = s;
2862 gen_not(b2);
2863
2864 /*
2865 * For management frames, the DA is at 4.
2866 */
2867 b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
2868 gen_and(b2, b1);
2869
2870 /*
2871 * OR that with the checks done for data frames.
2872 * That gives the checks done for management and
2873 * data frames.
2874 */
2875 gen_or(b1, b0);
2876
2877 /*
2878 * If the low-order bit of the type value is 1,
2879 * this is either a control frame or a frame
2880 * with a reserved type, and thus not a
2881 * frame with an SA.
2882 *
2883 * I.e., check "!(link[0] & 0x04)".
2884 */
2885 s = gen_load_a(OR_LINK, 0, BPF_B);
2886 b1 = new_block(JMP(BPF_JSET));
2887 b1->s.k = 0x04;
2888 b1->stmts = s;
2889 gen_not(b1);
2890
2891 /*
2892 * AND that with the checks for data and management
2893 * frames.
--- 27 unchanged lines hidden (view full) ---
2921gen_ipfchostop(eaddr, dir)
2922 register const u_char *eaddr;
2923 register int dir;
2924{
2925 register struct block *b0, *b1;
2926
2927 switch (dir) {
2928 case Q_SRC:
2929 return gen_bcmp(OR_LINK, 10, 6, eaddr);
2930
2931 case Q_DST:
2932 return gen_bcmp(OR_LINK, 2, 6, eaddr);
2933
2934 case Q_AND:
2935 b0 = gen_ipfchostop(eaddr, Q_SRC);
2936 b1 = gen_ipfchostop(eaddr, Q_DST);
2937 gen_and(b0, b1);
2938 return b1;
2939
2940 case Q_DEFAULT:
--- 21 unchanged lines hidden (view full) ---
2962 * will require a lot more hacking.
2963 *
2964 * To add support for filtering on DECNET "areas" (network numbers)
2965 * one would want to add a "mask" argument to this routine. That would
2966 * make the filter even more inefficient, although one could be clever
2967 * and not generate masking instructions if the mask is 0xFFFF.
2968 */
2969static struct block *
2970gen_dnhostop(addr, dir)
2971 bpf_u_int32 addr;
2972 int dir;
2973{
2974 struct block *b0, *b1, *b2, *tmp;
2975 u_int offset_lh; /* offset if long header is received */
2976 u_int offset_sh; /* offset if short header is received */
2977
2978 switch (dir) {
2979
2980 case Q_DST:
2981 offset_sh = 1; /* follows flags */
2982 offset_lh = 7; /* flgs,darea,dsubarea,HIORD */
2983 break;
2984
2985 case Q_SRC:
2986 offset_sh = 3; /* follows flags, dstnode */
2987 offset_lh = 15; /* flgs,darea,dsubarea,did,sarea,ssub,HIORD */
2988 break;
2989
2990 case Q_AND:
2991 /* Inefficient because we do our Calvinball dance twice */
2992 b0 = gen_dnhostop(addr, Q_SRC);
2993 b1 = gen_dnhostop(addr, Q_DST);
2994 gen_and(b0, b1);
2995 return b1;
2996
2997 case Q_OR:
2998 case Q_DEFAULT:
2999 /* Inefficient because we do our Calvinball dance twice */
3000 b0 = gen_dnhostop(addr, Q_SRC);
3001 b1 = gen_dnhostop(addr, Q_DST);
3002 gen_or(b0, b1);
3003 return b1;
3004
3005 case Q_ISO:
3006 bpf_error("ISO host filtering not implemented");
3007
3008 default:
3009 abort();
3010 }
3011 b0 = gen_linktype(ETHERTYPE_DN);
3012 /* Check for pad = 1, long header case */
3013 tmp = gen_mcmp(OR_NET, 2, BPF_H,
3014 (bpf_int32)ntohs(0x0681), (bpf_int32)ntohs(0x07FF));
3015 b1 = gen_cmp(OR_NET, 2 + 1 + offset_lh,
3016 BPF_H, (bpf_int32)ntohs(addr));
3017 gen_and(tmp, b1);
3018 /* Check for pad = 0, long header case */
3019 tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x06, (bpf_int32)0x7);
3020 b2 = gen_cmp(OR_NET, 2 + offset_lh, BPF_H, (bpf_int32)ntohs(addr));
3021 gen_and(tmp, b2);
3022 gen_or(b2, b1);
3023 /* Check for pad = 1, short header case */
3024 tmp = gen_mcmp(OR_NET, 2, BPF_H,
3025 (bpf_int32)ntohs(0x0281), (bpf_int32)ntohs(0x07FF));
3026 b2 = gen_cmp(OR_NET, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs(addr));
3027 gen_and(tmp, b2);
3028 gen_or(b2, b1);
3029 /* Check for pad = 0, short header case */
3030 tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x02, (bpf_int32)0x7);
3031 b2 = gen_cmp(OR_NET, 2 + offset_sh, BPF_H, (bpf_int32)ntohs(addr));
3032 gen_and(tmp, b2);
3033 gen_or(b2, b1);
3034
3035 /* Combine with test for linktype */
3036 gen_and(b0, b1);
3037 return b1;
3038}
3039
--- 14 unchanged lines hidden (view full) ---
3054 b1 = gen_host(addr, mask, Q_ARP, dir);
3055 gen_or(b0, b1);
3056 b0 = gen_host(addr, mask, Q_RARP, dir);
3057 gen_or(b1, b0);
3058 }
3059 return b0;
3060
3061 case Q_IP:
3062 return gen_hostop(addr, mask, dir, ETHERTYPE_IP, 12, 16);
3063
3064 case Q_RARP:
3065 return gen_hostop(addr, mask, dir, ETHERTYPE_REVARP, 14, 24);
3066
3067 case Q_ARP:
3068 return gen_hostop(addr, mask, dir, ETHERTYPE_ARP, 14, 24);
3069
3070 case Q_TCP:
3071 bpf_error("'tcp' modifier applied to host");
3072
3073 case Q_SCTP:
3074 bpf_error("'sctp' modifier applied to host");
3075
3076 case Q_UDP:
--- 16 unchanged lines hidden (view full) ---
3093
3094 case Q_ATALK:
3095 bpf_error("ATALK host filtering not implemented");
3096
3097 case Q_AARP:
3098 bpf_error("AARP host filtering not implemented");
3099
3100 case Q_DECNET:
3101 return gen_dnhostop(addr, dir);
3102
3103 case Q_SCA:
3104 bpf_error("SCA host filtering not implemented");
3105
3106 case Q_LAT:
3107 bpf_error("LAT host filtering not implemented");
3108
3109 case Q_MOPDL:
--- 32 unchanged lines hidden (view full) ---
3142 bpf_error("'stp' modifier applied to host");
3143
3144 case Q_IPX:
3145 bpf_error("IPX host filtering not implemented");
3146
3147 case Q_NETBEUI:
3148 bpf_error("'netbeui' modifier applied to host");
3149
3150 case Q_RADIO:
3151 bpf_error("'radio' modifier applied to host");
3152
3153 default:
3154 abort();
3155 }
3156 /* NOTREACHED */
3157}
3158
3159#ifdef INET6
3160static struct block *
--- 58 unchanged lines hidden (view full) ---
3219
3220 case Q_MOPDL:
3221 bpf_error("MOPDL host filtering not implemented");
3222
3223 case Q_MOPRC:
3224 bpf_error("MOPRC host filtering not implemented");
3225
3226 case Q_IPV6:
3227 return gen_hostop6(addr, mask, dir, ETHERTYPE_IPV6, 8, 24);
3228
3229 case Q_ICMPV6:
3230 bpf_error("'icmp6' modifier applied to host");
3231
3232 case Q_AH:
3233 bpf_error("'ah' modifier applied to host");
3234
3235 case Q_ESP:
--- 15 unchanged lines hidden (view full) ---
3251 bpf_error("'stp' modifier applied to host");
3252
3253 case Q_IPX:
3254 bpf_error("IPX host filtering not implemented");
3255
3256 case Q_NETBEUI:
3257 bpf_error("'netbeui' modifier applied to host");
3258
3259 case Q_RADIO:
3260 bpf_error("'radio' modifier applied to host");
3261
3262 default:
3263 abort();
3264 }
3265 /* NOTREACHED */
3266}
3267#endif /*INET6*/
3268
3269#ifndef INET6
--- 15 unchanged lines hidden (view full) ---
3285 case Q_ARP:
3286 case Q_RARP:
3287 if (linktype == DLT_EN10MB)
3288 b0 = gen_ehostop(eaddr, Q_OR);
3289 else if (linktype == DLT_FDDI)
3290 b0 = gen_fhostop(eaddr, Q_OR);
3291 else if (linktype == DLT_IEEE802)
3292 b0 = gen_thostop(eaddr, Q_OR);
3293 else if (linktype == DLT_IEEE802_11 ||
3294 linktype == DLT_IEEE802_11_RADIO_AVS ||
3295 linktype == DLT_IEEE802_11_RADIO ||
3296 linktype == DLT_PRISM_HEADER)
3297 b0 = gen_wlanhostop(eaddr, Q_OR);
3298 else if (linktype == DLT_SUNATM && is_lane) {
3299 /*
3300 * Check that the packet doesn't begin with an
3301 * LE Control marker. (We've already generated
3302 * a test for LANE.)
3303 */
3304 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
3305 0xFF00);
3306 gen_not(b1);
3307
3308 /*
3309 * Now check the MAC address.
3310 */
3311 b0 = gen_ehostop(eaddr, Q_OR);
3312 gen_and(b1, b0);
3313 } else if (linktype == DLT_IP_OVER_FC)
--- 250 unchanged lines hidden (view full) ---
3564 case Q_IPX:
3565 b1 = gen_linktype(LLCSAP_IPX);
3566 break;
3567
3568 case Q_NETBEUI:
3569 b1 = gen_linktype(LLCSAP_NETBEUI);
3570 break;
3571
3572 case Q_RADIO:
3573 bpf_error("'radio' is not a valid protocol type");
3574
3575 default:
3576 abort();
3577 }
3578 return b1;
3579}
3580
3581static struct block *
3582gen_ipfrag()
3583{
3584 struct slist *s;
3585 struct block *b;
3586
3587 /* not ip frag */
3588 s = gen_load_a(OR_NET, 6, BPF_H);
3589 b = new_block(JMP(BPF_JSET));
3590 b->s.k = 0x1fff;
3591 b->stmts = s;
3592 gen_not(b);
3593
3594 return b;
3595}
3596
3597/*
3598 * Generate a comparison to a port value in the transport-layer header
3599 * at the specified offset from the beginning of that header.
3600 *
3601 * XXX - this handles a variable-length prefix preceding the link-layer
3602 * header, such as the radiotap or AVS radio prefix, but doesn't handle
3603 * variable-length link-layer headers (such as Token Ring or 802.11
3604 * headers).
3605 */
3606static struct block *
3607gen_portatom(off, v)
3608 int off;
3609 bpf_int32 v;
3610{
3611 return gen_cmp(OR_TRAN_IPV4, off, BPF_H, v);
3612}
3613
3614#ifdef INET6
3615static struct block *
3616gen_portatom6(off, v)
3617 int off;
3618 bpf_int32 v;
3619{
3620 return gen_cmp(OR_TRAN_IPV6, off, BPF_H, v);
3621}
3622#endif/*INET6*/
3623
3624struct block *
3625gen_portop(port, proto, dir)
3626 int port, proto, dir;
3627{
3628 struct block *b0, *b1, *tmp;
3629
3630 /* ip proto 'proto' */
3631 tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto);
3632 b0 = gen_ipfrag();
3633 gen_and(tmp, b0);
3634
3635 switch (dir) {
3636 case Q_SRC:
3637 b1 = gen_portatom(0, (bpf_int32)port);
3638 break;
3639
--- 73 unchanged lines hidden (view full) ---
3713
3714#ifdef INET6
3715struct block *
3716gen_portop6(port, proto, dir)
3717 int port, proto, dir;
3718{
3719 struct block *b0, *b1, *tmp;
3720
3721 /* ip6 proto 'proto' */
3722 b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto);
3723
3724 switch (dir) {
3725 case Q_SRC:
3726 b1 = gen_portatom6(0, (bpf_int32)port);
3727 break;
3728
3729 case Q_DST:
3730 b1 = gen_portatom6(2, (bpf_int32)port);
--- 23 unchanged lines hidden (view full) ---
3754static struct block *
3755gen_port6(port, ip_proto, dir)
3756 int port;
3757 int ip_proto;
3758 int dir;
3759{
3760 struct block *b0, *b1, *tmp;
3761
3762 /* link proto ip6 */
3763 b0 = gen_linktype(ETHERTYPE_IPV6);
3764
3765 switch (ip_proto) {
3766 case IPPROTO_UDP:
3767 case IPPROTO_TCP:
3768 case IPPROTO_SCTP:
3769 b1 = gen_portop6(port, ip_proto, dir);
3770 break;
--- 9 unchanged lines hidden (view full) ---
3780 default:
3781 abort();
3782 }
3783 gen_and(b0, b1);
3784 return b1;
3785}
3786#endif /* INET6 */
3787
3788/* gen_portrange code */
3789static struct block *
3790gen_portrangeatom(off, v1, v2)
3791 int off;
3792 bpf_int32 v1, v2;
3793{
3794 struct block *b1, *b2;
3795
3796 if (v1 > v2) {
3797 /*
3798 * Reverse the order of the ports, so v1 is the lower one.
3799 */
3800 bpf_int32 vtemp;
3801
3802 vtemp = v1;
3803 v1 = v2;
3804 v2 = vtemp;
3805 }
3806
3807 b1 = gen_cmp_ge(OR_TRAN_IPV4, off, BPF_H, v1);
3808 b2 = gen_cmp_le(OR_TRAN_IPV4, off, BPF_H, v2);
3809
3810 gen_and(b1, b2);
3811
3812 return b2;
3813}
3814
3815struct block *
3816gen_portrangeop(port1, port2, proto, dir)
3817 int port1, port2;
3818 int proto;
3819 int dir;
3820{
3821 struct block *b0, *b1, *tmp;
3822
3823 /* ip proto 'proto' */
3824 tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto);
3825 b0 = gen_ipfrag();
3826 gen_and(tmp, b0);
3827
3828 switch (dir) {
3829 case Q_SRC:
3830 b1 = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
3831 break;
3832
3833 case Q_DST:
3834 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
3835 break;
3836
3837 case Q_OR:
3838 case Q_DEFAULT:
3839 tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
3840 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
3841 gen_or(tmp, b1);
3842 break;
3843
3844 case Q_AND:
3845 tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
3846 b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
3847 gen_and(tmp, b1);
3848 break;
3849
3850 default:
3851 abort();
3852 }
3853 gen_and(b0, b1);
3854
3855 return b1;
3856}
3857
3858static struct block *
3859gen_portrange(port1, port2, ip_proto, dir)
3860 int port1, port2;
3861 int ip_proto;
3862 int dir;
3863{
3864 struct block *b0, *b1, *tmp;
3865
3866 /* link proto ip */
3867 b0 = gen_linktype(ETHERTYPE_IP);
3868
3869 switch (ip_proto) {
3870 case IPPROTO_UDP:
3871 case IPPROTO_TCP:
3872 case IPPROTO_SCTP:
3873 b1 = gen_portrangeop(port1, port2, ip_proto, dir);
3874 break;
3875
3876 case PROTO_UNDEF:
3877 tmp = gen_portrangeop(port1, port2, IPPROTO_TCP, dir);
3878 b1 = gen_portrangeop(port1, port2, IPPROTO_UDP, dir);
3879 gen_or(tmp, b1);
3880 tmp = gen_portrangeop(port1, port2, IPPROTO_SCTP, dir);
3881 gen_or(tmp, b1);
3882 break;
3883
3884 default:
3885 abort();
3886 }
3887 gen_and(b0, b1);
3888 return b1;
3889}
3890
3891#ifdef INET6
3892static struct block *
3893gen_portrangeatom6(off, v1, v2)
3894 int off;
3895 bpf_int32 v1, v2;
3896{
3897 struct block *b1, *b2;
3898
3899 if (v1 > v2) {
3900 /*
3901 * Reverse the order of the ports, so v1 is the lower one.
3902 */
3903 bpf_int32 vtemp;
3904
3905 vtemp = v1;
3906 v1 = v2;
3907 v2 = vtemp;
3908 }
3909
3910 b1 = gen_cmp_ge(OR_TRAN_IPV6, off, BPF_H, v1);
3911 b2 = gen_cmp_le(OR_TRAN_IPV6, off, BPF_H, v2);
3912
3913 gen_and(b1, b2);
3914
3915 return b2;
3916}
3917
3918struct block *
3919gen_portrangeop6(port1, port2, proto, dir)
3920 int port1, port2;
3921 int proto;
3922 int dir;
3923{
3924 struct block *b0, *b1, *tmp;
3925
3926 /* ip6 proto 'proto' */
3927 b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto);
3928
3929 switch (dir) {
3930 case Q_SRC:
3931 b1 = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
3932 break;
3933
3934 case Q_DST:
3935 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
3936 break;
3937
3938 case Q_OR:
3939 case Q_DEFAULT:
3940 tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
3941 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
3942 gen_or(tmp, b1);
3943 break;
3944
3945 case Q_AND:
3946 tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
3947 b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
3948 gen_and(tmp, b1);
3949 break;
3950
3951 default:
3952 abort();
3953 }
3954 gen_and(b0, b1);
3955
3956 return b1;
3957}
3958
3959static struct block *
3960gen_portrange6(port1, port2, ip_proto, dir)
3961 int port1, port2;
3962 int ip_proto;
3963 int dir;
3964{
3965 struct block *b0, *b1, *tmp;
3966
3967 /* link proto ip6 */
3968 b0 = gen_linktype(ETHERTYPE_IPV6);
3969
3970 switch (ip_proto) {
3971 case IPPROTO_UDP:
3972 case IPPROTO_TCP:
3973 case IPPROTO_SCTP:
3974 b1 = gen_portrangeop6(port1, port2, ip_proto, dir);
3975 break;
3976
3977 case PROTO_UNDEF:
3978 tmp = gen_portrangeop6(port1, port2, IPPROTO_TCP, dir);
3979 b1 = gen_portrangeop6(port1, port2, IPPROTO_UDP, dir);
3980 gen_or(tmp, b1);
3981 tmp = gen_portrangeop6(port1, port2, IPPROTO_SCTP, dir);
3982 gen_or(tmp, b1);
3983 break;
3984
3985 default:
3986 abort();
3987 }
3988 gen_and(b0, b1);
3989 return b1;
3990}
3991#endif /* INET6 */
3992
3993static int
3994lookup_proto(name, proto)
3995 register const char *name;
3996 register int proto;
3997{
3998 register int v;
3999
4000 switch (proto) {
--- 72 unchanged lines hidden (view full) ---
4073 b = gen_protochain(v, Q_IPV6, dir);
4074 gen_or(b0, b);
4075 return b;
4076 default:
4077 bpf_error("bad protocol applied for 'protochain'");
4078 /*NOTREACHED*/
4079 }
4080
4081 /*
4082 * We don't handle variable-length radiotap here headers yet.
4083 * We might want to add BPF instructions to do the protochain
4084 * work, to simplify that and, on platforms that have a BPF
4085 * interpreter with the new instructions, let the filtering
4086 * be done in the kernel. (We already require a modified BPF
4087 * engine to do the protochain stuff, to support backward
4088 * branches, and backward branch support is unlikely to appear
4089 * in kernel BPF engines.)
4090 */
4091 if (linktype == DLT_IEEE802_11_RADIO)
4092 bpf_error("'protochain' not supported with radiotap headers");
4093
4094 no_optimize = 1; /*this code is not compatible with optimzer yet */
4095
4096 /*
4097 * s[0] is a dummy entry to protect other BPF insn from damage
4098 * by s[fix] = foo with uninitialized variable "fix". It is somewhat
4099 * hard to find interdependency made by jump table fixup.
4100 */
4101 i = 0;
4102 s[i] = new_stmt(0); /*dummy*/
4103 i++;
4104
4105 switch (proto) {
--- 239 unchanged lines hidden (view full) ---
4345
4346 free_reg(reg2);
4347
4348 gen_and(b0, b);
4349 return b;
4350#endif
4351}
4352
4353/*
4354 * Generate code that checks whether the packet is a packet for protocol
4355 * <proto> and whether the type field in that protocol's header has
4356 * the value <v>, e.g. if <proto> is Q_IP, it checks whether it's an
4357 * IP packet and checks the protocol number in the IP header against <v>.
4358 *
4359 * If <proto> is Q_DEFAULT, i.e. just "proto" was specified, it checks
4360 * against Q_IP and Q_IPV6.
4361 */
4362static struct block *
4363gen_proto(v, proto, dir)
4364 int v;
4365 int proto;
4366 int dir;
4367{
4368 struct block *b0, *b1;
4369
--- 23 unchanged lines hidden (view full) ---
4393 * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and
4394 * RFC 2225 say that SNAP encapsulation is used, not LLC
4395 * encapsulation with LLCSAP_IP.
4396 *
4397 * So we always check for ETHERTYPE_IP.
4398 */
4399 b0 = gen_linktype(ETHERTYPE_IP);
4400#ifndef CHASE_CHAIN
4401 b1 = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)v);
4402#else
4403 b1 = gen_protochain(v, Q_IP);
4404#endif
4405 gen_and(b0, b1);
4406 return b1;
4407
4408 case Q_ISO:
4409 switch (linktype) {
--- 12 unchanged lines hidden (view full) ---
4422 * control field value of UI, i.e. 0x03 followed
4423 * by the NLPID.
4424 *
4425 * XXX - assumes a 2-byte Frame Relay header with
4426 * DLCI and flags. What if the address is longer?
4427 *
4428 * XXX - what about SNAP-encapsulated frames?
4429 */
4430 return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | v);
4431 /*NOTREACHED*/
4432 break;
4433
4434 case DLT_C_HDLC:
4435 /*
4436 * Cisco uses an Ethertype lookalike - for OSI,
4437 * it's 0xfefe.
4438 */
4439 b0 = gen_linktype(LLCSAP_ISONS<<8 | LLCSAP_ISONS);
4440 /* OSI in C-HDLC is stuffed with a fudge byte */
4441 b1 = gen_cmp(OR_NET_NOSNAP, 1, BPF_B, (long)v);
4442 gen_and(b0, b1);
4443 return b1;
4444
4445 default:
4446 b0 = gen_linktype(LLCSAP_ISONS);
4447 b1 = gen_cmp(OR_NET_NOSNAP, 0, BPF_B, (long)v);
4448 gen_and(b0, b1);
4449 return b1;
4450 }
4451
4452 case Q_ISIS:
4453 b0 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
4454 /*
4455 * 4 is the offset of the PDU type relative to the IS-IS
4456 * header.
4457 */
4458 b1 = gen_cmp(OR_NET_NOSNAP, 4, BPF_B, (long)v);
4459 gen_and(b0, b1);
4460 return b1;
4461
4462 case Q_ARP:
4463 bpf_error("arp does not encapsulate another protocol");
4464 /* NOTREACHED */
4465
4466 case Q_RARP:
--- 58 unchanged lines hidden (view full) ---
4525 case Q_VRRP:
4526 bpf_error("'vrrp proto' is bogus");
4527 /* NOTREACHED */
4528
4529#ifdef INET6
4530 case Q_IPV6:
4531 b0 = gen_linktype(ETHERTYPE_IPV6);
4532#ifndef CHASE_CHAIN
4533 b1 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)v);
4534#else
4535 b1 = gen_protochain(v, Q_IPV6);
4536#endif
4537 gen_and(b0, b1);
4538 return b1;
4539
4540 case Q_ICMPV6:
4541 bpf_error("'icmp6 proto' is bogus");
--- 9 unchanged lines hidden (view full) ---
4551 bpf_error("'stp proto' is bogus");
4552
4553 case Q_IPX:
4554 bpf_error("'ipx proto' is bogus");
4555
4556 case Q_NETBEUI:
4557 bpf_error("'netbeui proto' is bogus");
4558
4559 case Q_RADIO:
4560 bpf_error("'radio proto' is bogus");
4561
4562 default:
4563 abort();
4564 /* NOTREACHED */
4565 }
4566 /* NOTREACHED */
4567}
4568
4569struct block *
--- 12 unchanged lines hidden (view full) ---
4582 int tproto6;
4583 struct sockaddr_in *sin;
4584 struct sockaddr_in6 *sin6;
4585 struct addrinfo *res, *res0;
4586 struct in6_addr mask128;
4587#endif /*INET6*/
4588 struct block *b, *tmp;
4589 int port, real_proto;
4590 int port1, port2;
4591
4592 switch (q.addr) {
4593
4594 case Q_NET:
4595 addr = pcap_nametonetaddr(name);
4596 if (addr == 0)
4597 bpf_error("unknown network '%s'", name);
4598 /* Left justify network addr and calculate its network mask */
--- 32 unchanged lines hidden (view full) ---
4631 if (eaddr == NULL)
4632 bpf_error(
4633 "unknown token ring host '%s'", name);
4634 b = gen_thostop(eaddr, dir);
4635 free(eaddr);
4636 return b;
4637
4638 case DLT_IEEE802_11:
4639 case DLT_IEEE802_11_RADIO_AVS:
4640 case DLT_IEEE802_11_RADIO:
4641 case DLT_PRISM_HEADER:
4642 eaddr = pcap_ether_hostton(name);
4643 if (eaddr == NULL)
4644 bpf_error(
4645 "unknown 802.11 host '%s'", name);
4646 b = gen_wlanhostop(eaddr, dir);
4647 free(eaddr);
4648 return b;
4649
--- 10 unchanged lines hidden (view full) ---
4660 if (!is_lane)
4661 break;
4662
4663 /*
4664 * Check that the packet doesn't begin
4665 * with an LE Control marker. (We've
4666 * already generated a test for LANE.)
4667 */
4668 tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS,
4669 BPF_H, 0xFF00);
4670 gen_not(tmp);
4671
4672 eaddr = pcap_ether_hostton(name);
4673 if (eaddr == NULL)
4674 bpf_error(
4675 "unknown ether host '%s'", name);
4676 b = gen_ehostop(eaddr, dir);
4677 gen_and(tmp, b);
--- 115 unchanged lines hidden (view full) ---
4793 {
4794 struct block *b;
4795 b = gen_port(port, real_proto, dir);
4796 gen_or(gen_port6(port, real_proto, dir), b);
4797 return b;
4798 }
4799#endif /* INET6 */
4800
4801 case Q_PORTRANGE:
4802 if (proto != Q_DEFAULT &&
4803 proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP)
4804 bpf_error("illegal qualifier of 'portrange'");
4805 if (pcap_nametoportrange(name, &port1, &port2, &real_proto) == 0)
4806 bpf_error("unknown port in range '%s'", name);
4807 if (proto == Q_UDP) {
4808 if (real_proto == IPPROTO_TCP)
4809 bpf_error("port in range '%s' is tcp", name);
4810 else if (real_proto == IPPROTO_SCTP)
4811 bpf_error("port in range '%s' is sctp", name);
4812 else
4813 /* override PROTO_UNDEF */
4814 real_proto = IPPROTO_UDP;
4815 }
4816 if (proto == Q_TCP) {
4817 if (real_proto == IPPROTO_UDP)
4818 bpf_error("port in range '%s' is udp", name);
4819 else if (real_proto == IPPROTO_SCTP)
4820 bpf_error("port in range '%s' is sctp", name);
4821 else
4822 /* override PROTO_UNDEF */
4823 real_proto = IPPROTO_TCP;
4824 }
4825 if (proto == Q_SCTP) {
4826 if (real_proto == IPPROTO_UDP)
4827 bpf_error("port in range '%s' is udp", name);
4828 else if (real_proto == IPPROTO_TCP)
4829 bpf_error("port in range '%s' is tcp", name);
4830 else
4831 /* override PROTO_UNDEF */
4832 real_proto = IPPROTO_SCTP;
4833 }
4834#ifndef INET6
4835 return gen_portrange(port1, port2, real_proto, dir);
4836#else
4837 {
4838 struct block *b;
4839 b = gen_portrange(port1, port2, real_proto, dir);
4840 gen_or(gen_portrange6(port1, port2, real_proto, dir), b);
4841 return b;
4842 }
4843#endif /* INET6 */
4844
4845 case Q_GATEWAY:
4846#ifndef INET6
4847 eaddr = pcap_ether_hostton(name);
4848 if (eaddr == NULL)
4849 bpf_error("unknown ether host: %s", name);
4850
4851 alist = pcap_nametoaddr(name);
4852 if (alist == NULL || *alist == NULL)
--- 131 unchanged lines hidden (view full) ---
4984 {
4985 struct block *b;
4986 b = gen_port((int)v, proto, dir);
4987 gen_or(gen_port6((int)v, proto, dir), b);
4988 return b;
4989 }
4990#endif /* INET6 */
4991
4992 case Q_PORTRANGE:
4993 if (proto == Q_UDP)
4994 proto = IPPROTO_UDP;
4995 else if (proto == Q_TCP)
4996 proto = IPPROTO_TCP;
4997 else if (proto == Q_SCTP)
4998 proto = IPPROTO_SCTP;
4999 else if (proto == Q_DEFAULT)
5000 proto = PROTO_UNDEF;
5001 else
5002 bpf_error("illegal qualifier of 'portrange'");
5003
5004#ifndef INET6
5005 return gen_portrange((int)v, (int)v, proto, dir);
5006#else
5007 {
5008 struct block *b;
5009 b = gen_portrange((int)v, (int)v, proto, dir);
5010 gen_or(gen_portrange6((int)v, (int)v, proto, dir), b);
5011 return b;
5012 }
5013#endif /* INET6 */
5014
5015 case Q_GATEWAY:
5016 bpf_error("'gateway' requires a name");
5017 /* NOTREACHED */
5018
5019 case Q_PROTO:
5020 return gen_proto((int)v, proto, dir);
5021
5022 case Q_PROTOCHAIN:
--- 78 unchanged lines hidden (view full) ---
5101
5102 if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) {
5103 if (linktype == DLT_EN10MB)
5104 return gen_ehostop(eaddr, (int)q.dir);
5105 if (linktype == DLT_FDDI)
5106 return gen_fhostop(eaddr, (int)q.dir);
5107 if (linktype == DLT_IEEE802)
5108 return gen_thostop(eaddr, (int)q.dir);
5109 if (linktype == DLT_IEEE802_11 ||
5110 linktype == DLT_IEEE802_11_RADIO_AVS ||
5111 linktype == DLT_IEEE802_11_RADIO ||
5112 linktype == DLT_PRISM_HEADER)
5113 return gen_wlanhostop(eaddr, (int)q.dir);
5114 if (linktype == DLT_SUNATM && is_lane) {
5115 /*
5116 * Check that the packet doesn't begin with an
5117 * LE Control marker. (We've already generated
5118 * a test for LANE.)
5119 */
5120 tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
5121 0xFF00);
5122 gen_not(tmp);
5123
5124 /*
5125 * Now check the MAC address.
5126 */
5127 b = gen_ehostop(eaddr, (int)q.dir);
5128 gen_and(tmp, b);
5129 return b;
--- 36 unchanged lines hidden (view full) ---
5166{
5167 struct slist *s;
5168
5169 s = new_stmt(BPF_LD|BPF_MEM);
5170 s->s.k = a->regno;
5171 return s;
5172}
5173
5174/*
5175 * Modify "index" to use the value stored into its register as an
5176 * offset relative to the beginning of the header for the protocol
5177 * "proto", and allocate a register and put an item "size" bytes long
5178 * (1, 2, or 4) at that offset into that register, making it the register
5179 * for "index".
5180 */
5181struct arth *
5182gen_load(proto, index, size)
5183 int proto;
5184 struct arth *index;
5185 int size;
5186{
5187 struct slist *s, *tmp;
5188 struct block *b;
--- 16 unchanged lines hidden (view full) ---
5205 case 4:
5206 size = BPF_W;
5207 break;
5208 }
5209 switch (proto) {
5210 default:
5211 bpf_error("unsupported index operation");
5212
5213 case Q_RADIO:
5214 /*
5215 * The offset is relative to the beginning of the packet
5216 * data, if we have a radio header. (If we don't, this
5217 * is an error.)
5218 */
5219 if (linktype != DLT_IEEE802_11_RADIO_AVS &&
5220 linktype != DLT_IEEE802_11_RADIO &&
5221 linktype != DLT_PRISM_HEADER)
5222 bpf_error("radio information not present in capture");
5223
5224 /*
5225 * Load into the X register the offset computed into the
5226 * register specifed by "index".
5227 */
5228 s = xfer_to_x(index);
5229
5230 /*
5231 * Load the item at that offset.
5232 */
5233 tmp = new_stmt(BPF_LD|BPF_IND|size);
5234 sappend(s, tmp);
5235 sappend(index->s, s);
5236 break;
5237
5238 case Q_LINK:
5239 /*
5240 * The offset is relative to the beginning of
5241 * the link-layer header.
5242 *
5243 * XXX - what about ATM LANE? Should the index be
5244 * relative to the beginning of the AAL5 frame, so
5245 * that 0 refers to the beginning of the LE Control
5246 * field, or relative to the beginning of the LAN
5247 * frame, so that 0 refers, for Ethernet LANE, to
5248 * the beginning of the destination address?
5249 */
5250 s = gen_llprefixlen();
5251
5252 /*
5253 * If "s" is non-null, it has code to arrange that the
5254 * X register contains the length of the prefix preceding
5255 * the link-layer header. Add to it the offset computed
5256 * into the register specified by "index", and move that
5257 * into the X register. Otherwise, just load into the X
5258 * register the offset computed into the register specifed
5259 * by "index".
5260 */
5261 if (s != NULL) {
5262 sappend(s, xfer_to_a(index));
5263 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
5264 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
5265 } else
5266 s = xfer_to_x(index);
5267
5268 /*
5269 * Load the item at the sum of the offset we've put in the
5270 * X register and the offset of the start of the link
5271 * layer header (which is 0 if the radio header is
5272 * variable-length; that header length is what we put
5273 * into the X register and then added to the index).
5274 */
5275 tmp = new_stmt(BPF_LD|BPF_IND|size);
5276 tmp->s.k = off_ll;
5277 sappend(s, tmp);
5278 sappend(index->s, s);
5279 break;
5280
5281 case Q_IP:
5282 case Q_ARP:
5283 case Q_RARP:
5284 case Q_ATALK:
5285 case Q_DECNET:
5286 case Q_SCA:
5287 case Q_LAT:
5288 case Q_MOPRC:
5289 case Q_MOPDL:
5290#ifdef INET6
5291 case Q_IPV6:
5292#endif
5293 /*
5294 * The offset is relative to the beginning of
5295 * the network-layer header.
5296 * XXX - are there any cases where we want
5297 * off_nl_nosnap?
5298 */
5299 s = gen_llprefixlen();
5300
5301 /*
5302 * If "s" is non-null, it has code to arrange that the
5303 * X register contains the length of the prefix preceding
5304 * the link-layer header. Add to it the offset computed
5305 * into the register specified by "index", and move that
5306 * into the X register. Otherwise, just load into the X
5307 * register the offset computed into the register specifed
5308 * by "index".
5309 */
5310 if (s != NULL) {
5311 sappend(s, xfer_to_a(index));
5312 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
5313 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
5314 } else
5315 s = xfer_to_x(index);
5316
5317 /*
5318 * Load the item at the sum of the offset we've put in the
5319 * X register and the offset of the start of the network
5320 * layer header.
5321 */
5322 tmp = new_stmt(BPF_LD|BPF_IND|size);
5323 tmp->s.k = off_nl;
5324 sappend(s, tmp);
5325 sappend(index->s, s);
5326
5327 /*
5328 * Do the computation only if the packet contains
5329 * the protocol in question.
5330 */
5331 b = gen_proto_abbrev(proto);
5332 if (index->b)
5333 gen_and(index->b, b);
5334 index->b = b;
5335 break;
5336
5337 case Q_SCTP:
5338 case Q_TCP:
5339 case Q_UDP:
5340 case Q_ICMP:
5341 case Q_IGMP:
5342 case Q_IGRP:
5343 case Q_PIM:
5344 case Q_VRRP:
5345 /*
5346 * The offset is relative to the beginning of
5347 * the transport-layer header.
5348 * XXX - are there any cases where we want
5349 * off_nl_nosnap?
5350 * XXX - we should, if we're built with
5351 * IPv6 support, generate code to load either
5352 * IPv4, IPv6, or both, as appropriate.
5353 */
5354 s = gen_loadx_iphdrlen();
5355
5356 /*
5357 * The X register now contains the sum of the offset
5358 * of the beginning of the link-layer header and
5359 * the length of the network-layer header. Load
5360 * into the A register the offset relative to
5361 * the beginning of the transport layer header,
5362 * add the X register to that, move that to the
5363 * X register, and load with an offset from the
5364 * X register equal to the offset of the network
5365 * layer header relative to the beginning of
5366 * the link-layer header.
5367 */
5368 sappend(s, xfer_to_a(index));
5369 sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
5370 sappend(s, new_stmt(BPF_MISC|BPF_TAX));
5371 sappend(s, tmp = new_stmt(BPF_LD|BPF_IND|size));
5372 tmp->s.k = off_nl;
5373 sappend(index->s, s);
5374
5375 /*
5376 * Do the computation only if the packet contains
5377 * the protocol in question - which is true only
5378 * if this is an IP datagram and is the first or
5379 * only fragment of that datagram.
5380 */
5381 gen_and(gen_proto_abbrev(proto), b = gen_ipfrag());
5382 if (index->b)
5383 gen_and(index->b, b);
5384#ifdef INET6
5385 gen_and(gen_proto_abbrev(Q_IP), b);
5386#endif
5387 index->b = b;
5388 break;
--- 209 unchanged lines hidden (view full) ---
5598 struct block *b;
5599
5600 b = gen_len(BPF_JGT, n);
5601 gen_not(b);
5602
5603 return b;
5604}
5605
5606/*
5607 * This is for "byte {idx} {op} {val}"; "idx" is treated as relative to
5608 * the beginning of the link-layer header.
5609 * XXX - that means you can't test values in the radiotap header, but
5610 * as that header is difficult if not impossible to parse generally
5611 * without a loop, that might not be a severe problem. A new keyword
5612 * "radio" could be added for that, although what you'd really want
5613 * would be a way of testing particular radio header values, which
5614 * would generate code appropriate to the radio header in question.
5615 */
5616struct block *
5617gen_byteop(op, idx, val)
5618 int op, idx, val;
5619{
5620 struct block *b;
5621 struct slist *s;
5622
5623 switch (op) {
5624 default:
5625 abort();
5626
5627 case '=':
5628 return gen_cmp(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
5629
5630 case '<':
5631 b = gen_cmp_lt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
5632 return b;
5633
5634 case '>':
5635 b = gen_cmp_gt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
5636 return b;
5637
5638 case '|':
5639 s = new_stmt(BPF_ALU|BPF_OR|BPF_K);
5640 break;
5641
5642 case '&':
5643 s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
--- 24 unchanged lines hidden (view full) ---
5668 if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX)
5669 return gen_ahostop(abroadcast, Q_DST);
5670 if (linktype == DLT_EN10MB)
5671 return gen_ehostop(ebroadcast, Q_DST);
5672 if (linktype == DLT_FDDI)
5673 return gen_fhostop(ebroadcast, Q_DST);
5674 if (linktype == DLT_IEEE802)
5675 return gen_thostop(ebroadcast, Q_DST);
5676 if (linktype == DLT_IEEE802_11 ||
5677 linktype == DLT_IEEE802_11_RADIO_AVS ||
5678 linktype == DLT_IEEE802_11_RADIO ||
5679 linktype == DLT_PRISM_HEADER)
5680 return gen_wlanhostop(ebroadcast, Q_DST);
5681 if (linktype == DLT_IP_OVER_FC)
5682 return gen_ipfchostop(ebroadcast, Q_DST);
5683 if (linktype == DLT_SUNATM && is_lane) {
5684 /*
5685 * Check that the packet doesn't begin with an
5686 * LE Control marker. (We've already generated
5687 * a test for LANE.)
5688 */
5689 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
5690 0xFF00);
5691 gen_not(b1);
5692
5693 /*
5694 * Now check the MAC address.
5695 */
5696 b0 = gen_ehostop(ebroadcast, Q_DST);
5697 gen_and(b1, b0);
5698 return b0;
5699 }
5700 bpf_error("not a broadcast link");
5701 break;
5702
5703 case Q_IP:
5704 b0 = gen_linktype(ETHERTYPE_IP);
5705 hostmask = ~netmask;
5706 b1 = gen_mcmp(OR_NET, 16, BPF_W, (bpf_int32)0, hostmask);
5707 b2 = gen_mcmp(OR_NET, 16, BPF_W,
5708 (bpf_int32)(~0 & hostmask), hostmask);
5709 gen_or(b1, b2);
5710 gen_and(b0, b2);
5711 return b2;
5712 }
5713 bpf_error("only link-layer/IP broadcast filters supported");
5714 /* NOTREACHED */
5715}
--- 5 unchanged lines hidden (view full) ---
5721static struct block *
5722gen_mac_multicast(offset)
5723 int offset;
5724{
5725 register struct block *b0;
5726 register struct slist *s;
5727
5728 /* link[offset] & 1 != 0 */
5729 s = gen_load_a(OR_LINK, offset, BPF_B);
5730 b0 = new_block(JMP(BPF_JSET));
5731 b0->s.k = 1;
5732 b0->stmts = s;
5733 return b0;
5734}
5735
5736struct block *
5737gen_multicast(proto)
--- 25 unchanged lines hidden (view full) ---
5763 return gen_mac_multicast(1);
5764 }
5765
5766 if (linktype == DLT_IEEE802) {
5767 /* tr[2] & 1 != 0 */
5768 return gen_mac_multicast(2);
5769 }
5770
5771 if (linktype == DLT_IEEE802_11 ||
5772 linktype == DLT_IEEE802_11_RADIO_AVS ||
5773 linktype == DLT_IEEE802_11_RADIO ||
5774 linktype == DLT_PRISM_HEADER) {
5775 /*
5776 * Oh, yuk.
5777 *
5778 * For control frames, there is no DA.
5779 *
5780 * For management frames, DA is at an
5781 * offset of 4 from the beginning of
5782 * the packet.
--- 5 unchanged lines hidden (view full) ---
5788 * if To DS is set.
5789 */
5790
5791 /*
5792 * Generate the tests to be done for data frames.
5793 *
5794 * First, check for To DS set, i.e. "link[1] & 0x01".
5795 */
5796 s = gen_load_a(OR_LINK, 1, BPF_B);
5797 b1 = new_block(JMP(BPF_JSET));
5798 b1->s.k = 0x01; /* To DS */
5799 b1->stmts = s;
5800
5801 /*
5802 * If To DS is set, the DA is at 16.
5803 */
5804 b0 = gen_mac_multicast(16);
5805 gen_and(b1, b0);
5806
5807 /*
5808 * Now, check for To DS not set, i.e. check
5809 * "!(link[1] & 0x01)".
5810 */
5811 s = gen_load_a(OR_LINK, 1, BPF_B);
5812 b2 = new_block(JMP(BPF_JSET));
5813 b2->s.k = 0x01; /* To DS */
5814 b2->stmts = s;
5815 gen_not(b2);
5816
5817 /*
5818 * If To DS is not set, the DA is at 4.
5819 */
--- 5 unchanged lines hidden (view full) ---
5825 * the complete set of checks for data frames.
5826 */
5827 gen_or(b1, b0);
5828
5829 /*
5830 * Now check for a data frame.
5831 * I.e, check "link[0] & 0x08".
5832 */
5833 s = gen_load_a(OR_LINK, 0, BPF_B);
5834 b1 = new_block(JMP(BPF_JSET));
5835 b1->s.k = 0x08;
5836 b1->stmts = s;
5837
5838 /*
5839 * AND that with the checks done for data frames.
5840 */
5841 gen_and(b1, b0);
5842
5843 /*
5844 * If the high-order bit of the type value is 0, this
5845 * is a management frame.
5846 * I.e, check "!(link[0] & 0x08)".
5847 */
5848 s = gen_load_a(OR_LINK, 0, BPF_B);
5849 b2 = new_block(JMP(BPF_JSET));
5850 b2->s.k = 0x08;
5851 b2->stmts = s;
5852 gen_not(b2);
5853
5854 /*
5855 * For management frames, the DA is at 4.
5856 */
--- 10 unchanged lines hidden (view full) ---
5867 /*
5868 * If the low-order bit of the type value is 1,
5869 * this is either a control frame or a frame
5870 * with a reserved type, and thus not a
5871 * frame with an SA.
5872 *
5873 * I.e., check "!(link[0] & 0x04)".
5874 */
5875 s = gen_load_a(OR_LINK, 0, BPF_B);
5876 b1 = new_block(JMP(BPF_JSET));
5877 b1->s.k = 0x04;
5878 b1->stmts = s;
5879 gen_not(b1);
5880
5881 /*
5882 * AND that with the checks for data and management
5883 * frames.
--- 8 unchanged lines hidden (view full) ---
5892 }
5893
5894 if (linktype == DLT_SUNATM && is_lane) {
5895 /*
5896 * Check that the packet doesn't begin with an
5897 * LE Control marker. (We've already generated
5898 * a test for LANE.)
5899 */
5900 b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
5901 0xFF00);
5902 gen_not(b1);
5903
5904 /* ether[off_mac] & 1 != 0 */
5905 b0 = gen_mac_multicast(off_mac);
5906 gen_and(b1, b0);
5907 return b0;
5908 }
5909
5910 /* Link not known to support multicasts */
5911 break;
5912
5913 case Q_IP:
5914 b0 = gen_linktype(ETHERTYPE_IP);
5915 b1 = gen_cmp_ge(OR_NET, 16, BPF_B, (bpf_int32)224);
5916 gen_and(b0, b1);
5917 return b1;
5918
5919#ifdef INET6
5920 case Q_IPV6:
5921 b0 = gen_linktype(ETHERTYPE_IPV6);
5922 b1 = gen_cmp(OR_NET, 24, BPF_B, (bpf_int32)255);
5923 gen_and(b0, b1);
5924 return b1;
5925#endif /* INET6 */
5926 }
5927 bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel");
5928 /* NOTREACHED */
5929}
5930
--- 19 unchanged lines hidden (view full) ---
5950 dir);
5951 break;
5952
5953 case DLT_LINUX_SLL:
5954 if (dir) {
5955 /*
5956 * Match packets sent by this machine.
5957 */
5958 b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_OUTGOING);
5959 } else {
5960 /*
5961 * Match packets sent to this machine.
5962 * (No broadcast or multicast packets, or
5963 * packets sent to some other machine and
5964 * received promiscuously.)
5965 *
5966 * XXX - packets sent to other machines probably
5967 * shouldn't be matched, but what about broadcast
5968 * or multicast packets we received?
5969 */
5970 b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_HOST);
5971 }
5972 break;
5973
5974 case DLT_PFLOG:
5975 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, dir), BPF_B,
5976 (bpf_int32)((dir == 0) ? PF_IN : PF_OUT));
5977 break;
5978
5979 case DLT_PPP_PPPD:
5980 if (dir) {
5981 /* match outgoing packets */
5982 b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_OUT);
5983 } else {
5984 /* match incoming packets */
5985 b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_IN);
5986 }
5987 break;
5988
5989 case DLT_JUNIPER_MLFR:
5990 case DLT_JUNIPER_MLPPP:
5991 case DLT_JUNIPER_ATM1:
5992 case DLT_JUNIPER_ATM2:
5993 case DLT_JUNIPER_PPPOE:
5994 case DLT_JUNIPER_PPPOE_ATM:
5995 case DLT_JUNIPER_GGSN:
5996 case DLT_JUNIPER_ES:
5997 case DLT_JUNIPER_MONITOR:
5998 case DLT_JUNIPER_SERVICES:
5999 /* juniper flags (including direction) are stored
6000 * the byte after the 3-byte magic number */
6001 if (dir) {
6002 /* match outgoing packets */
6003 b0 = gen_mcmp(OR_LINK, 3, BPF_B, 0, 0x01);
6004 } else {
6005 /* match incoming packets */
6006 b0 = gen_mcmp(OR_LINK, 3, BPF_B, 1, 0x01);
6007 }
6008 break;
6009
6010 default:
6011 bpf_error("inbound/outbound not supported on linktype %d",
6012 linktype);
6013 b0 = NULL;
6014 /* NOTREACHED */
--- 15 unchanged lines hidden (view full) ---
6030 bpf_error("ifname not supported on linktype 0x%x", linktype);
6031 /* NOTREACHED */
6032 }
6033 if (strlen(ifname) >= len) {
6034 bpf_error("ifname interface names can only be %d characters",
6035 len-1);
6036 /* NOTREACHED */
6037 }
6038 b0 = gen_bcmp(OR_LINK, off, strlen(ifname), (const u_char *)ifname);
6039 return (b0);
6040}
6041
6042/* PF firewall log matched interface */
6043struct block *
6044gen_pf_ruleset(char *ruleset)
6045{
6046 struct block *b0;
6047
6048 if (linktype != DLT_PFLOG) {
6049 bpf_error("ruleset not supported on linktype 0x%x", linktype);
6050 /* NOTREACHED */
6051 }
6052 if (strlen(ruleset) >= sizeof(((struct pfloghdr *)0)->ruleset)) {
6053 bpf_error("ruleset names can only be %ld characters",
6054 (long)(sizeof(((struct pfloghdr *)0)->ruleset) - 1));
6055 /* NOTREACHED */
6056 }
6057 b0 = gen_bcmp(OR_LINK, offsetof(struct pfloghdr, ruleset),
6058 strlen(ruleset), (const u_char *)ruleset);
6059 return (b0);
6060}
6061
6062/* PF firewall log rule number */
6063struct block *
6064gen_pf_rnr(int rnr)
6065{
6066 struct block *b0;
6067
6068 if (linktype == DLT_PFLOG) {
6069 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, rulenr), BPF_W,
6070 (bpf_int32)rnr);
6071 } else {
6072 bpf_error("rnr not supported on linktype 0x%x", linktype);
6073 /* NOTREACHED */
6074 }
6075
6076 return (b0);
6077}
--- 4 unchanged lines hidden (view full) ---
6082{
6083 struct block *b0;
6084
6085 if (linktype != DLT_PFLOG) {
6086 bpf_error("srnr not supported on linktype 0x%x", linktype);
6087 /* NOTREACHED */
6088 }
6089
6090 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, subrulenr), BPF_W,
6091 (bpf_int32)srnr);
6092 return (b0);
6093}
6094
6095/* PF firewall log reason code */
6096struct block *
6097gen_pf_reason(int reason)
6098{
6099 struct block *b0;
6100
6101 if (linktype == DLT_PFLOG) {
6102 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, reason), BPF_B,
6103 (bpf_int32)reason);
6104 } else {
6105 bpf_error("reason not supported on linktype 0x%x", linktype);
6106 /* NOTREACHED */
6107 }
6108
6109 return (b0);
6110}
6111
6112/* PF firewall log action */
6113struct block *
6114gen_pf_action(int action)
6115{
6116 struct block *b0;
6117
6118 if (linktype == DLT_PFLOG) {
6119 b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, action), BPF_B,
6120 (bpf_int32)action);
6121 } else {
6122 bpf_error("action not supported on linktype 0x%x", linktype);
6123 /* NOTREACHED */
6124 }
6125
6126 return (b0);
6127}
--- 16 unchanged lines hidden (view full) ---
6144 register const u_char *eaddr;
6145 register int dir;
6146{
6147 register struct block *b0, *b1;
6148
6149 switch (dir) {
6150 /* src comes first, different from Ethernet */
6151 case Q_SRC:
6152 return gen_bcmp(OR_LINK, 0, 1, eaddr);
6153
6154 case Q_DST:
6155 return gen_bcmp(OR_LINK, 1, 1, eaddr);
6156
6157 case Q_AND:
6158 b0 = gen_ahostop(eaddr, Q_SRC);
6159 b1 = gen_ahostop(eaddr, Q_DST);
6160 gen_and(b0, b1);
6161 return b1;
6162
6163 case Q_DEFAULT:
--- 13 unchanged lines hidden (view full) ---
6177struct block *
6178gen_vlan(vlan_num)
6179 int vlan_num;
6180{
6181 struct block *b0;
6182
6183 /*
6184 * Change the offsets to point to the type and data fields within
6185 * the VLAN packet. Just increment the offsets, so that we
6186 * can support a hierarchy, e.g. "vlan 300 && vlan 200" to
6187 * capture VLAN 200 encapsulated within VLAN 100.
6188 *
6189 * XXX - this is a bit of a kludge. If we were to split the
6190 * compiler into a parser that parses an expression and
6191 * generates an expression tree, and a code generator that
6192 * takes an expression tree (which could come from our
6193 * parser or from some other parser) and generates BPF code,
6194 * we could perhaps make the offsets parameters of routines
6195 * and, in the handler for an "AND" node, pass to subnodes
6196 * other than the VLAN node the adjusted offsets.
6197 *
6198 * This would mean that "vlan" would, instead of changing the
6199 * behavior of *all* tests after it, change only the behavior
6200 * of tests ANDed with it. That would change the documented
6201 * semantics of "vlan", which might break some expressions.
6202 * However, it would mean that "(vlan and ip) or ip" would check
6203 * both for VLAN-encapsulated IP and IP-over-Ethernet, rather than
6204 * checking only for VLAN-encapsulated IP, so that could still
6205 * be considered worth doing; it wouldn't break expressions
6206 * that are of the form "vlan and ..." or "vlan N and ...",
6207 * which I suspect are the most common expressions involving
6208 * "vlan". "vlan or ..." doesn't necessarily do what the user
6209 * would really want, now, as all the "or ..." tests would
6210 * be done assuming a VLAN, even though the "or" could be viewed
6211 * as meaning "or, if this isn't a VLAN packet...".
6212 */
6213 orig_linktype = off_linktype; /* save original values */
6214 orig_nl = off_nl;
6215
6216 switch (linktype) {
6217
6218 case DLT_EN10MB:
6219 off_linktype += 4;
6220 off_nl_nosnap += 4;
6221 off_nl += 4;
6222 break;
6223
6224 default:
6225 bpf_error("no VLAN support for data link type %d",
6226 linktype);
6227 /*NOTREACHED*/
6228 }
6229
6230 /* check for VLAN */
6231 b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H, (bpf_int32)ETHERTYPE_8021Q);
6232
6233 /* If a specific VLAN is requested, check VLAN id */
6234 if (vlan_num >= 0) {
6235 struct block *b1;
6236
6237 b1 = gen_mcmp(OR_LINK, orig_nl, BPF_H, (bpf_int32)vlan_num,
6238 0x0fff);
6239 gen_and(b0, b1);
6240 b0 = b1;
6241 }
6242
6243 return (b0);
6244}
6245
6246/*
6247 * support for MPLS
6248 */
6249struct block *
6250gen_mpls(label_num)
6251 int label_num;
6252{
6253 struct block *b0;
6254
6255 /*
6256 * Change the offsets to point to the type and data fields within
6257 * the MPLS packet. Just increment the offsets, so that we
6258 * can support a hierarchy, e.g. "mpls 100000 && mpls 1024" to
6259 * capture packets with an outer label of 100000 and an inner
6260 * label of 1024.
6261 *
6262 * XXX - this is a bit of a kludge. See comments in gen_vlan().
6263 */
6264 orig_linktype = off_linktype; /* save original values */
6265 orig_nl = off_nl;
6266
6267 switch (linktype) {
6268
6269 case DLT_C_HDLC: /* fall through */
6270 case DLT_EN10MB:
6271 off_nl_nosnap += 4;
6272 off_nl += 4;
6273
6274 b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H,
6275 (bpf_int32)ETHERTYPE_MPLS);
6276 break;
6277
6278 case DLT_PPP:
6279 off_nl_nosnap += 4;
6280 off_nl += 4;
6281
6282 b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H,
6283 (bpf_int32)PPP_MPLS_UCAST);
6284 break;
6285
6286 /* FIXME add other DLT_s ...
6287 * for Frame-Relay/and ATM this may get messy due to SNAP headers
6288 * leave it for now */
6289
6290 default:
6291 bpf_error("no MPLS support for data link type %d",
6292 linktype);
6293 b0 = NULL;
6294 /*NOTREACHED*/
6295 break;
6296 }
6297
6298 /* If a specific MPLS label is requested, check it */
6299 if (label_num >= 0) {
6300 struct block *b1;
6301
6302 label_num = label_num << 12; /* label is shifted 12 bits on the wire */
6303 b1 = gen_mcmp(OR_LINK, orig_nl, BPF_W, (bpf_int32)label_num,
6304 0xfffff000); /* only compare the first 20 bits */
6305 gen_and(b0, b1);
6306 b0 = b1;
6307 }
6308
6309 return (b0);
6310}
6311
6312struct block *
6313gen_atmfield_code(atmfield, jvalue, jtype, reverse)
6314 int atmfield;
6315 bpf_int32 jvalue;
6316 bpf_u_int32 jtype;
6317 int reverse;
6318{
6319 struct block *b0;
6320
6321 switch (atmfield) {
6322
6323 case A_VPI:
6324 if (!is_atm)
6325 bpf_error("'vpi' supported only on raw ATM");
6326 if (off_vpi == (u_int)-1)
6327 abort();
6328 b0 = gen_ncmp(OR_LINK, off_vpi, BPF_B, 0xffffffff, jtype,
6329 reverse, jvalue);
6330 break;
6331
6332 case A_VCI:
6333 if (!is_atm)
6334 bpf_error("'vci' supported only on raw ATM");
6335 if (off_vci == (u_int)-1)
6336 abort();
6337 b0 = gen_ncmp(OR_LINK, off_vci, BPF_H, 0xffffffff, jtype,
6338 reverse, jvalue);
6339 break;
6340
6341 case A_PROTOTYPE:
6342 if (off_proto == (u_int)-1)
6343 abort(); /* XXX - this isn't on FreeBSD */
6344 b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0x0f, jtype,
6345 reverse, jvalue);
6346 break;
6347
6348 case A_MSGTYPE:
6349 if (off_payload == (u_int)-1)
6350 abort();
6351 b0 = gen_ncmp(OR_LINK, off_payload + MSG_TYPE_POS, BPF_B,
6352 0xffffffff, jtype, reverse, jvalue);
6353 break;
6354
6355 case A_CALLREFTYPE:
6356 if (!is_atm)
6357 bpf_error("'callref' supported only on raw ATM");
6358 if (off_proto == (u_int)-1)
6359 abort();
6360 b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0xffffffff,
6361 jtype, reverse, jvalue);
6362 break;
6363
6364 default:
6365 abort();
6366 }
6367 return b0;
6368}
6369
--- 93 unchanged lines hidden (view full) ---
6463 break;
6464
6465 default:
6466 abort();
6467 }
6468 return b1;
6469}
6470
6471struct block *
6472gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
6473 int mtp3field;
6474 bpf_u_int32 jvalue;
6475 bpf_u_int32 jtype;
6476 int reverse;
6477{
6478 struct block *b0;
6479 bpf_u_int32 val1 , val2 , val3;
6480
6481 switch (mtp3field) {
6482
6483 case M_SIO:
6484 if (off_sio == (u_int)-1)
6485 bpf_error("'sio' supported only on SS7");
6486 /* sio coded on 1 byte so max value 255 */
6487 if(jvalue > 255)
6488 bpf_error("sio value %u too big; max value = 255",
6489 jvalue);
6490 b0 = gen_ncmp(OR_PACKET, off_sio, BPF_B, 0xffffffff,
6491 (u_int)jtype, reverse, (u_int)jvalue);
6492 break;
6493
6494 case M_OPC:
6495 if (off_opc == (u_int)-1)
6496 bpf_error("'opc' supported only on SS7");
6497 /* opc coded on 14 bits so max value 16383 */
6498 if (jvalue > 16383)
6499 bpf_error("opc value %u too big; max value = 16383",
6500 jvalue);
6501 /* the following instructions are made to convert jvalue
6502 * to the form used to write opc in an ss7 message*/
6503 val1 = jvalue & 0x00003c00;
6504 val1 = val1 >>10;
6505 val2 = jvalue & 0x000003fc;
6506 val2 = val2 <<6;
6507 val3 = jvalue & 0x00000003;
6508 val3 = val3 <<22;
6509 jvalue = val1 + val2 + val3;
6510 b0 = gen_ncmp(OR_PACKET, off_opc, BPF_W, 0x00c0ff0f,
6511 (u_int)jtype, reverse, (u_int)jvalue);
6512 break;
6513
6514 case M_DPC:
6515 if (off_dpc == (u_int)-1)
6516 bpf_error("'dpc' supported only on SS7");
6517 /* dpc coded on 14 bits so max value 16383 */
6518 if (jvalue > 16383)
6519 bpf_error("dpc value %u too big; max value = 16383",
6520 jvalue);
6521 /* the following instructions are made to convert jvalue
6522 * to the forme used to write dpc in an ss7 message*/
6523 val1 = jvalue & 0x000000ff;
6524 val1 = val1 << 24;
6525 val2 = jvalue & 0x00003f00;
6526 val2 = val2 << 8;
6527 jvalue = val1 + val2;
6528 b0 = gen_ncmp(OR_PACKET, off_dpc, BPF_W, 0xff3f0000,
6529 (u_int)jtype, reverse, (u_int)jvalue);
6530 break;
6531
6532 case M_SLS:
6533 if (off_sls == (u_int)-1)
6534 bpf_error("'sls' supported only on SS7");
6535 /* sls coded on 4 bits so max value 15 */
6536 if (jvalue > 15)
6537 bpf_error("sls value %u too big; max value = 15",
6538 jvalue);
6539 /* the following instruction is made to convert jvalue
6540 * to the forme used to write sls in an ss7 message*/
6541 jvalue = jvalue << 4;
6542 b0 = gen_ncmp(OR_PACKET, off_sls, BPF_B, 0xf0,
6543 (u_int)jtype,reverse, (u_int)jvalue);
6544 break;
6545
6546 default:
6547 abort();
6548 }
6549 return b0;
6550}
6551
6552static struct block *
6553gen_msg_abbrev(type)
6554 int type;
6555{
6556 struct block *b1;
6557
6558 /*
6559 * Q.2931 signalling protocol messages for handling virtual circuits
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