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authorIliyan Malchev <malchev@google.com>2009-04-28 14:09:07 -0700
committerIliyan Malchev <malchev@google.com>2009-04-28 14:09:07 -0700
commitf341270e30dd82bf004f2b87cacae1482ca4d50e (patch)
treed3f5b9a0008ddbf53ae3e623271a0ec0dda47072
parent478ab6c8b5bc982589be32eae1e5736efe721b58 (diff)
downloadlibpcap-f341270e30dd82bf004f2b87cacae1482ca4d50e.tar.gz
Signed-off-by: Iliyan Malchev <malchev@google.com>
-rw-r--r--gencode.c.orig7192
1 files changed, 0 insertions, 7192 deletions
diff --git a/gencode.c.orig b/gencode.c.orig
deleted file mode 100644
index 5067abc6..00000000
--- a/gencode.c.orig
+++ /dev/null
@@ -1,7192 +0,0 @@
-/*#define CHASE_CHAIN*/
-/*
- * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998
- * The Regents of the University of California. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that: (1) source code distributions
- * retain the above copyright notice and this paragraph in its entirety, (2)
- * distributions including binary code include the above copyright notice and
- * this paragraph in its entirety in the documentation or other materials
- * provided with the distribution, and (3) all advertising materials mentioning
- * features or use of this software display the following acknowledgement:
- * ``This product includes software developed by the University of California,
- * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
- * the University nor the names of its contributors may be used to endorse
- * or promote products derived from this software without specific prior
- * written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
- */
-#ifndef lint
-static const char rcsid[] _U_ =
- "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.52 2007/06/22 06:43:58 guy Exp $ (LBL)";
-#endif
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#ifdef WIN32
-#include <pcap-stdinc.h>
-#else /* WIN32 */
-#include <sys/types.h>
-#include <sys/socket.h>
-#endif /* WIN32 */
-
-/*
- * XXX - why was this included even on UNIX?
- */
-#ifdef __MINGW32__
-#include "IP6_misc.h"
-#endif
-
-#ifndef WIN32
-
-#ifdef __NetBSD__
-#include <sys/param.h>
-#endif
-
-#include <netinet/in.h>
-
-#endif /* WIN32 */
-
-#include <stdlib.h>
-#include <string.h>
-#include <memory.h>
-#include <setjmp.h>
-#include <stdarg.h>
-
-#ifdef MSDOS
-#include "pcap-dos.h"
-#endif
-
-#include "pcap-int.h"
-
-#include "ethertype.h"
-#include "nlpid.h"
-#include "llc.h"
-#include "gencode.h"
-#include "atmuni31.h"
-#include "sunatmpos.h"
-#include "ppp.h"
-#include "sll.h"
-#include "arcnet.h"
-#include "pf.h"
-#ifndef offsetof
-#define offsetof(s, e) ((size_t)&((s *)0)->e)
-#endif
-#ifdef INET6
-#ifndef WIN32
-#include <netdb.h> /* for "struct addrinfo" */
-#endif /* WIN32 */
-#endif /*INET6*/
-#include <pcap-namedb.h>
-
-#define ETHERMTU 1500
-
-#ifndef IPPROTO_SCTP
-#define IPPROTO_SCTP 132
-#endif
-
-#ifdef HAVE_OS_PROTO_H
-#include "os-proto.h"
-#endif
-
-#define JMP(c) ((c)|BPF_JMP|BPF_K)
-
-/* Locals */
-static jmp_buf top_ctx;
-static pcap_t *bpf_pcap;
-
-#ifdef WIN32
-/* Hack for updating VLAN, MPLS, and PPPoE offsets. */
-static u_int orig_linktype = (u_int)-1, orig_nl = (u_int)-1, label_stack_depth = (u_int)-1;
-#else
-static u_int orig_linktype = -1U, orig_nl = -1U, label_stack_depth = -1U;
-#endif
-
-/* XXX */
-#ifdef PCAP_FDDIPAD
-static int pcap_fddipad;
-#endif
-
-/* VARARGS */
-void
-bpf_error(const char *fmt, ...)
-{
- va_list ap;
-
- va_start(ap, fmt);
- if (bpf_pcap != NULL)
- (void)vsnprintf(pcap_geterr(bpf_pcap), PCAP_ERRBUF_SIZE,
- fmt, ap);
- va_end(ap);
- longjmp(top_ctx, 1);
- /* NOTREACHED */
-}
-
-static void init_linktype(pcap_t *);
-
-static int alloc_reg(void);
-static void free_reg(int);
-
-static struct block *root;
-
-/*
- * Value passed to gen_load_a() to indicate what the offset argument
- * is relative to.
- */
-enum e_offrel {
- OR_PACKET, /* relative to the beginning of the packet */
- OR_LINK, /* relative to the link-layer header */
- OR_NET, /* relative to the network-layer header */
- OR_NET_NOSNAP, /* relative to the network-layer header, with no SNAP header at the link layer */
- OR_TRAN_IPV4, /* relative to the transport-layer header, with IPv4 network layer */
- OR_TRAN_IPV6 /* relative to the transport-layer header, with IPv6 network layer */
-};
-
-/*
- * We divy out chunks of memory rather than call malloc each time so
- * we don't have to worry about leaking memory. It's probably
- * not a big deal if all this memory was wasted but if this ever
- * goes into a library that would probably not be a good idea.
- *
- * XXX - this *is* in a library....
- */
-#define NCHUNKS 16
-#define CHUNK0SIZE 1024
-struct chunk {
- u_int n_left;
- void *m;
-};
-
-static struct chunk chunks[NCHUNKS];
-static int cur_chunk;
-
-static void *newchunk(u_int);
-static void freechunks(void);
-static inline struct block *new_block(int);
-static inline struct slist *new_stmt(int);
-static struct block *gen_retblk(int);
-static inline void syntax(void);
-
-static void backpatch(struct block *, struct block *);
-static void merge(struct block *, struct block *);
-static struct block *gen_cmp(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_gt(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_ge(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_lt(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_cmp_le(enum e_offrel, u_int, u_int, bpf_int32);
-static struct block *gen_mcmp(enum e_offrel, u_int, u_int, bpf_int32,
- bpf_u_int32);
-static struct block *gen_bcmp(enum e_offrel, u_int, u_int, const u_char *);
-static struct block *gen_ncmp(enum e_offrel, bpf_u_int32, bpf_u_int32,
- bpf_u_int32, bpf_u_int32, int, bpf_int32);
-static struct slist *gen_load_llrel(u_int, u_int);
-static struct slist *gen_load_a(enum e_offrel, u_int, u_int);
-static struct slist *gen_loadx_iphdrlen(void);
-static struct block *gen_uncond(int);
-static inline struct block *gen_true(void);
-static inline struct block *gen_false(void);
-static struct block *gen_ether_linktype(int);
-static struct block *gen_linux_sll_linktype(int);
-static void insert_radiotap_load_llprefixlen(struct block *);
-static void insert_ppi_load_llprefixlen(struct block *);
-static void insert_load_llprefixlen(struct block *);
-static struct slist *gen_llprefixlen(void);
-static struct block *gen_linktype(int);
-static struct block *gen_snap(bpf_u_int32, bpf_u_int32, u_int);
-static struct block *gen_llc_linktype(int);
-static struct block *gen_hostop(bpf_u_int32, bpf_u_int32, int, int, u_int, u_int);
-#ifdef INET6
-static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int);
-#endif
-static struct block *gen_ahostop(const u_char *, int);
-static struct block *gen_ehostop(const u_char *, int);
-static struct block *gen_fhostop(const u_char *, int);
-static struct block *gen_thostop(const u_char *, int);
-static struct block *gen_wlanhostop(const u_char *, int);
-static struct block *gen_ipfchostop(const u_char *, int);
-static struct block *gen_dnhostop(bpf_u_int32, int);
-static struct block *gen_mpls_linktype(int);
-static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int, int);
-#ifdef INET6
-static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int, int);
-#endif
-#ifndef INET6
-static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int);
-#endif
-static struct block *gen_ipfrag(void);
-static struct block *gen_portatom(int, bpf_int32);
-static struct block *gen_portrangeatom(int, bpf_int32, bpf_int32);
-#ifdef INET6
-static struct block *gen_portatom6(int, bpf_int32);
-static struct block *gen_portrangeatom6(int, bpf_int32, bpf_int32);
-#endif
-struct block *gen_portop(int, int, int);
-static struct block *gen_port(int, int, int);
-struct block *gen_portrangeop(int, int, int, int);
-static struct block *gen_portrange(int, int, int, int);
-#ifdef INET6
-struct block *gen_portop6(int, int, int);
-static struct block *gen_port6(int, int, int);
-struct block *gen_portrangeop6(int, int, int, int);
-static struct block *gen_portrange6(int, int, int, int);
-#endif
-static int lookup_proto(const char *, int);
-static struct block *gen_protochain(int, int, int);
-static struct block *gen_proto(int, int, int);
-static struct slist *xfer_to_x(struct arth *);
-static struct slist *xfer_to_a(struct arth *);
-static struct block *gen_mac_multicast(int);
-static struct block *gen_len(int, int);
-
-static struct block *gen_ppi_dlt_check(void);
-static struct block *gen_msg_abbrev(int type);
-
-static void *
-newchunk(n)
- u_int n;
-{
- struct chunk *cp;
- int k;
- size_t size;
-
-#ifndef __NetBSD__
- /* XXX Round up to nearest long. */
- n = (n + sizeof(long) - 1) & ~(sizeof(long) - 1);
-#else
- /* XXX Round up to structure boundary. */
- n = ALIGN(n);
-#endif
-
- cp = &chunks[cur_chunk];
- if (n > cp->n_left) {
- ++cp, k = ++cur_chunk;
- if (k >= NCHUNKS)
- bpf_error("out of memory");
- size = CHUNK0SIZE << k;
- cp->m = (void *)malloc(size);
- if (cp->m == NULL)
- bpf_error("out of memory");
- memset((char *)cp->m, 0, size);
- cp->n_left = size;
- if (n > size)
- bpf_error("out of memory");
- }
- cp->n_left -= n;
- return (void *)((char *)cp->m + cp->n_left);
-}
-
-static void
-freechunks()
-{
- int i;
-
- cur_chunk = 0;
- for (i = 0; i < NCHUNKS; ++i)
- if (chunks[i].m != NULL) {
- free(chunks[i].m);
- chunks[i].m = NULL;
- }
-}
-
-/*
- * A strdup whose allocations are freed after code generation is over.
- */
-char *
-sdup(s)
- register const char *s;
-{
- int n = strlen(s) + 1;
- char *cp = newchunk(n);
-
- strlcpy(cp, s, n);
- return (cp);
-}
-
-static inline struct block *
-new_block(code)
- int code;
-{
- struct block *p;
-
- p = (struct block *)newchunk(sizeof(*p));
- p->s.code = code;
- p->head = p;
-
- return p;
-}
-
-static inline struct slist *
-new_stmt(code)
- int code;
-{
- struct slist *p;
-
- p = (struct slist *)newchunk(sizeof(*p));
- p->s.code = code;
-
- return p;
-}
-
-static struct block *
-gen_retblk(v)
- int v;
-{
- struct block *b = new_block(BPF_RET|BPF_K);
-
- b->s.k = v;
- return b;
-}
-
-static inline void
-syntax()
-{
- bpf_error("syntax error in filter expression");
-}
-
-static bpf_u_int32 netmask;
-static int snaplen;
-int no_optimize;
-
-int
-pcap_compile(pcap_t *p, struct bpf_program *program,
- const char *buf, int optimize, bpf_u_int32 mask)
-{
- extern int n_errors;
- const char * volatile xbuf = buf;
- int len;
-
- no_optimize = 0;
- n_errors = 0;
- root = NULL;
- bpf_pcap = p;
- if (setjmp(top_ctx)) {
- lex_cleanup();
- freechunks();
- return (-1);
- }
-
- netmask = mask;
-
- snaplen = pcap_snapshot(p);
- if (snaplen == 0) {
- snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
- "snaplen of 0 rejects all packets");
- return -1;
- }
-
- lex_init(xbuf ? xbuf : "");
- init_linktype(p);
- (void)pcap_parse();
-
- if (n_errors)
- syntax();
-
- if (root == NULL)
- root = gen_retblk(snaplen);
-
- if (optimize && !no_optimize) {
- bpf_optimize(&root);
- if (root == NULL ||
- (root->s.code == (BPF_RET|BPF_K) && root->s.k == 0))
- bpf_error("expression rejects all packets");
- }
- program->bf_insns = icode_to_fcode(root, &len);
- program->bf_len = len;
-
- lex_cleanup();
- freechunks();
- return (0);
-}
-
-/*
- * entry point for using the compiler with no pcap open
- * pass in all the stuff that is needed explicitly instead.
- */
-int
-pcap_compile_nopcap(int snaplen_arg, int linktype_arg,
- struct bpf_program *program,
- const char *buf, int optimize, bpf_u_int32 mask)
-{
- pcap_t *p;
- int ret;
-
- p = pcap_open_dead(linktype_arg, snaplen_arg);
- if (p == NULL)
- return (-1);
- ret = pcap_compile(p, program, buf, optimize, mask);
- pcap_close(p);
- return (ret);
-}
-
-/*
- * Clean up a "struct bpf_program" by freeing all the memory allocated
- * in it.
- */
-void
-pcap_freecode(struct bpf_program *program)
-{
- program->bf_len = 0;
- if (program->bf_insns != NULL) {
- free((char *)program->bf_insns);
- program->bf_insns = NULL;
- }
-}
-
-/*
- * Backpatch the blocks in 'list' to 'target'. The 'sense' field indicates
- * which of the jt and jf fields has been resolved and which is a pointer
- * back to another unresolved block (or nil). At least one of the fields
- * in each block is already resolved.
- */
-static void
-backpatch(list, target)
- struct block *list, *target;
-{
- struct block *next;
-
- while (list) {
- if (!list->sense) {
- next = JT(list);
- JT(list) = target;
- } else {
- next = JF(list);
- JF(list) = target;
- }
- list = next;
- }
-}
-
-/*
- * Merge the lists in b0 and b1, using the 'sense' field to indicate
- * which of jt and jf is the link.
- */
-static void
-merge(b0, b1)
- struct block *b0, *b1;
-{
- register struct block **p = &b0;
-
- /* Find end of list. */
- while (*p)
- p = !((*p)->sense) ? &JT(*p) : &JF(*p);
-
- /* Concatenate the lists. */
- *p = b1;
-}
-
-
-void
-finish_parse(p)
- struct block *p;
-{
- struct block *ppi_dlt_check;
-
- ppi_dlt_check = gen_ppi_dlt_check();
-
- if (ppi_dlt_check != NULL)
- {
- gen_and(ppi_dlt_check, p);
- }
-
- backpatch(p, gen_retblk(snaplen));
- p->sense = !p->sense;
- backpatch(p, gen_retblk(0));
- root = p->head;
-
- /*
- * Insert before the statements of the first (root) block any
- * statements needed to load the lengths of any variable-length
- * headers into registers.
- *
- * XXX - a fancier strategy would be to insert those before the
- * statements of all blocks that use those lengths and that
- * have no predecessors that use them, so that we only compute
- * the lengths if we need them. There might be even better
- * approaches than that. However, as we're currently only
- * handling variable-length radiotap headers, and as all
- * filtering expressions other than raw link[M:N] tests
- * require the length of that header, doing more for that
- * header length isn't really worth the effort.
- */
-
- insert_load_llprefixlen(root);
-}
-
-void
-gen_and(b0, b1)
- struct block *b0, *b1;
-{
- backpatch(b0, b1->head);
- b0->sense = !b0->sense;
- b1->sense = !b1->sense;
- merge(b1, b0);
- b1->sense = !b1->sense;
- b1->head = b0->head;
-}
-
-void
-gen_or(b0, b1)
- struct block *b0, *b1;
-{
- b0->sense = !b0->sense;
- backpatch(b0, b1->head);
- b0->sense = !b0->sense;
- merge(b1, b0);
- b1->head = b0->head;
-}
-
-void
-gen_not(b)
- struct block *b;
-{
- b->sense = !b->sense;
-}
-
-static struct block *
-gen_cmp(offrel, offset, size, v)
- enum e_offrel offrel;
- u_int offset, size;
- bpf_int32 v;
-{
- return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JEQ, 0, v);
-}
-
-static struct block *
-gen_cmp_gt(offrel, offset, size, v)
- enum e_offrel offrel;
- u_int offset, size;
- bpf_int32 v;
-{
- return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 0, v);
-}
-
-static struct block *
-gen_cmp_ge(offrel, offset, size, v)
- enum e_offrel offrel;
- u_int offset, size;
- bpf_int32 v;
-{
- return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 0, v);
-}
-
-static struct block *
-gen_cmp_lt(offrel, offset, size, v)
- enum e_offrel offrel;
- u_int offset, size;
- bpf_int32 v;
-{
- return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGE, 1, v);
-}
-
-static struct block *
-gen_cmp_le(offrel, offset, size, v)
- enum e_offrel offrel;
- u_int offset, size;
- bpf_int32 v;
-{
- return gen_ncmp(offrel, offset, size, 0xffffffff, BPF_JGT, 1, v);
-}
-
-static struct block *
-gen_mcmp(offrel, offset, size, v, mask)
- enum e_offrel offrel;
- u_int offset, size;
- bpf_int32 v;
- bpf_u_int32 mask;
-{
- return gen_ncmp(offrel, offset, size, mask, BPF_JEQ, 0, v);
-}
-
-static struct block *
-gen_bcmp(offrel, offset, size, v)
- enum e_offrel offrel;
- register u_int offset, size;
- register const u_char *v;
-{
- register struct block *b, *tmp;
-
- b = NULL;
- while (size >= 4) {
- register const u_char *p = &v[size - 4];
- bpf_int32 w = ((bpf_int32)p[0] << 24) |
- ((bpf_int32)p[1] << 16) | ((bpf_int32)p[2] << 8) | p[3];
-
- tmp = gen_cmp(offrel, offset + size - 4, BPF_W, w);
- if (b != NULL)
- gen_and(b, tmp);
- b = tmp;
- size -= 4;
- }
- while (size >= 2) {
- register const u_char *p = &v[size - 2];
- bpf_int32 w = ((bpf_int32)p[0] << 8) | p[1];
-
- tmp = gen_cmp(offrel, offset + size - 2, BPF_H, w);
- if (b != NULL)
- gen_and(b, tmp);
- b = tmp;
- size -= 2;
- }
- if (size > 0) {
- tmp = gen_cmp(offrel, offset, BPF_B, (bpf_int32)v[0]);
- if (b != NULL)
- gen_and(b, tmp);
- b = tmp;
- }
- return b;
-}
-
-/*
- * AND the field of size "size" at offset "offset" relative to the header
- * specified by "offrel" with "mask", and compare it with the value "v"
- * with the test specified by "jtype"; if "reverse" is true, the test
- * should test the opposite of "jtype".
- */
-static struct block *
-gen_ncmp(offrel, offset, size, mask, jtype, reverse, v)
- enum e_offrel offrel;
- bpf_int32 v;
- bpf_u_int32 offset, size, mask, jtype;
- int reverse;
-{
- struct slist *s, *s2;
- struct block *b;
-
- s = gen_load_a(offrel, offset, size);
-
- if (mask != 0xffffffff) {
- s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
- s2->s.k = mask;
- sappend(s, s2);
- }
-
- b = new_block(JMP(jtype));
- b->stmts = s;
- b->s.k = v;
- if (reverse && (jtype == BPF_JGT || jtype == BPF_JGE))
- gen_not(b);
- return b;
-}
-
-/*
- * Various code constructs need to know the layout of the data link
- * layer. These variables give the necessary offsets from the beginning
- * of the packet data.
- *
- * If the link layer has variable_length headers, the offsets are offsets
- * from the end of the link-link-layer header, and "reg_ll_size" is
- * the register number for a register containing the length of the
- * link-layer header. Otherwise, "reg_ll_size" is -1.
- */
-static int reg_ll_size;
-
-/*
- * This is the offset of the beginning of the link-layer header from
- * the beginning of the raw packet data.
- *
- * It's usually 0, except for 802.11 with a fixed-length radio header.
- * (For 802.11 with a variable-length radio header, we have to generate
- * code to compute that offset; off_ll is 0 in that case.)
- */
-static u_int off_ll;
-
-/*
- * This is the offset of the beginning of the MAC-layer header.
- * It's usually 0, except for ATM LANE, where it's the offset, relative
- * to the beginning of the raw packet data, of the Ethernet header.
- */
-static u_int off_mac;
-
-/*
- * "off_linktype" is the offset to information in the link-layer header
- * giving the packet type. This offset is relative to the beginning
- * of the link-layer header (i.e., it doesn't include off_ll).
- *
- * For Ethernet, it's the offset of the Ethernet type field.
- *
- * For link-layer types that always use 802.2 headers, it's the
- * offset of the LLC header.
- *
- * For PPP, it's the offset of the PPP type field.
- *
- * For Cisco HDLC, it's the offset of the CHDLC type field.
- *
- * For BSD loopback, it's the offset of the AF_ value.
- *
- * For Linux cooked sockets, it's the offset of the type field.
- *
- * It's set to -1 for no encapsulation, in which case, IP is assumed.
- */
-static u_int off_linktype;
-
-/*
- * TRUE if the link layer includes an ATM pseudo-header.
- */
-static int is_atm = 0;
-
-/*
- * TRUE if "lane" appeared in the filter; it causes us to generate
- * code that assumes LANE rather than LLC-encapsulated traffic in SunATM.
- */
-static int is_lane = 0;
-
-/*
- * These are offsets for the ATM pseudo-header.
- */
-static u_int off_vpi;
-static u_int off_vci;
-static u_int off_proto;
-
-/*
- * These are offsets for the MTP2 fields.
- */
-static u_int off_li;
-
-/*
- * These are offsets for the MTP3 fields.
- */
-static u_int off_sio;
-static u_int off_opc;
-static u_int off_dpc;
-static u_int off_sls;
-
-/*
- * This is the offset of the first byte after the ATM pseudo_header,
- * or -1 if there is no ATM pseudo-header.
- */
-static u_int off_payload;
-
-/*
- * These are offsets to the beginning of the network-layer header.
- * They are relative to the beginning of the link-layer header (i.e.,
- * they don't include off_ll).
- *
- * If the link layer never uses 802.2 LLC:
- *
- * "off_nl" and "off_nl_nosnap" are the same.
- *
- * If the link layer always uses 802.2 LLC:
- *
- * "off_nl" is the offset if there's a SNAP header following
- * the 802.2 header;
- *
- * "off_nl_nosnap" is the offset if there's no SNAP header.
- *
- * If the link layer is Ethernet:
- *
- * "off_nl" is the offset if the packet is an Ethernet II packet
- * (we assume no 802.3+802.2+SNAP);
- *
- * "off_nl_nosnap" is the offset if the packet is an 802.3 packet
- * with an 802.2 header following it.
- */
-static u_int off_nl;
-static u_int off_nl_nosnap;
-
-static int linktype;
-
-static void
-init_linktype(p)
- pcap_t *p;
-{
- linktype = pcap_datalink(p);
-#ifdef PCAP_FDDIPAD
- pcap_fddipad = p->fddipad;
-#endif
-
- /*
- * Assume it's not raw ATM with a pseudo-header, for now.
- */
- off_mac = 0;
- is_atm = 0;
- is_lane = 0;
- off_vpi = -1;
- off_vci = -1;
- off_proto = -1;
- off_payload = -1;
-
- /*
- * And assume we're not doing SS7.
- */
- off_li = -1;
- off_sio = -1;
- off_opc = -1;
- off_dpc = -1;
- off_sls = -1;
-
- /*
- * Also assume it's not 802.11 with a fixed-length radio header.
- */
- off_ll = 0;
-
- orig_linktype = -1;
- orig_nl = -1;
- label_stack_depth = 0;
-
- reg_ll_size = -1;
-
- switch (linktype) {
-
- case DLT_ARCNET:
- off_linktype = 2;
- off_nl = 6; /* XXX in reality, variable! */
- off_nl_nosnap = 6; /* no 802.2 LLC */
- return;
-
- case DLT_ARCNET_LINUX:
- off_linktype = 4;
- off_nl = 8; /* XXX in reality, variable! */
- off_nl_nosnap = 8; /* no 802.2 LLC */
- return;
-
- case DLT_EN10MB:
- off_linktype = 12;
- off_nl = 14; /* Ethernet II */
- off_nl_nosnap = 17; /* 802.3+802.2 */
- return;
-
- case DLT_SLIP:
- /*
- * SLIP doesn't have a link level type. The 16 byte
- * header is hacked into our SLIP driver.
- */
- off_linktype = -1;
- off_nl = 16;
- off_nl_nosnap = 16; /* no 802.2 LLC */
- return;
-
- case DLT_SLIP_BSDOS:
- /* XXX this may be the same as the DLT_PPP_BSDOS case */
- off_linktype = -1;
- /* XXX end */
- off_nl = 24;
- off_nl_nosnap = 24; /* no 802.2 LLC */
- return;
-
- case DLT_NULL:
- case DLT_LOOP:
- off_linktype = 0;
- off_nl = 4;
- off_nl_nosnap = 4; /* no 802.2 LLC */
- return;
-
- case DLT_ENC:
- off_linktype = 0;
- off_nl = 12;
- off_nl_nosnap = 12; /* no 802.2 LLC */
- return;
-
- case DLT_PPP:
- case DLT_PPP_PPPD:
- case DLT_C_HDLC: /* BSD/OS Cisco HDLC */
- case DLT_PPP_SERIAL: /* NetBSD sync/async serial PPP */
- off_linktype = 2;
- off_nl = 4;
- off_nl_nosnap = 4; /* no 802.2 LLC */
- return;
-
- case DLT_PPP_ETHER:
- /*
- * This does no include the Ethernet header, and
- * only covers session state.
- */
- off_linktype = 6;
- off_nl = 8;
- off_nl_nosnap = 8; /* no 802.2 LLC */
- return;
-
- case DLT_PPP_BSDOS:
- off_linktype = 5;
- off_nl = 24;
- off_nl_nosnap = 24; /* no 802.2 LLC */
- return;
-
- case DLT_FDDI:
- /*
- * FDDI doesn't really have a link-level type field.
- * We set "off_linktype" to the offset of the LLC header.
- *
- * To check for Ethernet types, we assume that SSAP = SNAP
- * is being used and pick out the encapsulated Ethernet type.
- * XXX - should we generate code to check for SNAP?
- */
- off_linktype = 13;
-#ifdef PCAP_FDDIPAD
- off_linktype += pcap_fddipad;
-#endif
- off_nl = 21; /* FDDI+802.2+SNAP */
- off_nl_nosnap = 16; /* FDDI+802.2 */
-#ifdef PCAP_FDDIPAD
- off_nl += pcap_fddipad;
- off_nl_nosnap += pcap_fddipad;
-#endif
- return;
-
- case DLT_IEEE802:
- /*
- * Token Ring doesn't really have a link-level type field.
- * We set "off_linktype" to the offset of the LLC header.
- *
- * To check for Ethernet types, we assume that SSAP = SNAP
- * is being used and pick out the encapsulated Ethernet type.
- * XXX - should we generate code to check for SNAP?
- *
- * XXX - the header is actually variable-length.
- * Some various Linux patched versions gave 38
- * as "off_linktype" and 40 as "off_nl"; however,
- * if a token ring packet has *no* routing
- * information, i.e. is not source-routed, the correct
- * values are 20 and 22, as they are in the vanilla code.
- *
- * A packet is source-routed iff the uppermost bit
- * of the first byte of the source address, at an
- * offset of 8, has the uppermost bit set. If the
- * packet is source-routed, the total number of bytes
- * of routing information is 2 plus bits 0x1F00 of
- * the 16-bit value at an offset of 14 (shifted right
- * 8 - figure out which byte that is).
- */
- off_linktype = 14;
- off_nl = 22; /* Token Ring+802.2+SNAP */
- off_nl_nosnap = 17; /* Token Ring+802.2 */
- return;
-
- case DLT_IEEE802_11:
- /*
- * 802.11 doesn't really have a link-level type field.
- * We set "off_linktype" to the offset of the LLC header.
- *
- * To check for Ethernet types, we assume that SSAP = SNAP
- * is being used and pick out the encapsulated Ethernet type.
- * XXX - should we generate code to check for SNAP?
- *
- * XXX - the header is actually variable-length. We
- * assume a 24-byte link-layer header, as appears in
- * data frames in networks with no bridges. If the
- * fromds and tods 802.11 header bits are both set,
- * it's actually supposed to be 30 bytes.
- */
- off_linktype = 24;
- off_nl = 32; /* 802.11+802.2+SNAP */
- off_nl_nosnap = 27; /* 802.11+802.2 */
- return;
-
- case DLT_PRISM_HEADER:
- /*
- * Same as 802.11, but with an additional header before
- * the 802.11 header, containing a bunch of additional
- * information including radio-level information.
- *
- * The header is 144 bytes long.
- *
- * XXX - same variable-length header problem; at least
- * the Prism header is fixed-length.
- */
- off_ll = 144;
- off_linktype = 24;
- off_nl = 32; /* Prism+802.11+802.2+SNAP */
- off_nl_nosnap = 27; /* Prism+802.11+802.2 */
- return;
-
- case DLT_IEEE802_11_RADIO_AVS:
- /*
- * Same as 802.11, but with an additional header before
- * the 802.11 header, containing a bunch of additional
- * information including radio-level information.
- *
- * The header is 64 bytes long, at least in its
- * current incarnation.
- *
- * XXX - same variable-length header problem, only
- * more so; this header is also variable-length,
- * with the length being the 32-bit big-endian
- * number at an offset of 4 from the beginning
- * of the radio header. We should handle that the
- * same way we handle the length at the beginning
- * of the radiotap header.
- *
- * XXX - in Linux, do any drivers that supply an AVS
- * header supply a link-layer type other than
- * ARPHRD_IEEE80211_PRISM? If so, we should map that
- * to DLT_IEEE802_11_RADIO_AVS; if not, or if there are
- * any drivers that supply an AVS header but supply
- * an ARPHRD value of ARPHRD_IEEE80211_PRISM, we'll
- * have to check the header in the generated code to
- * determine whether it's Prism or AVS.
- */
- off_ll = 64;
- off_linktype = 24;
- off_nl = 32; /* Radio+802.11+802.2+SNAP */
- off_nl_nosnap = 27; /* Radio+802.11+802.2 */
- return;
-
-
- /*
- * At the moment we treat PPI as normal Radiotap encoded
- * packets. The difference is in the function that generates
- * the code at the beginning to compute the header length.
- * Since this code generator of PPI supports bare 802.11
- * encapsulation only (i.e. the encapsulated DLT should be
- * DLT_IEEE802_11) we generate code to check for this too.
- */
- case DLT_PPI:
- case DLT_IEEE802_11_RADIO:
- /*
- * Same as 802.11, but with an additional header before
- * the 802.11 header, containing a bunch of additional
- * information including radio-level information.
- *
- * The radiotap header is variable length, and we
- * generate code to compute its length and store it
- * in a register. These offsets are relative to the
- * beginning of the 802.11 header.
- */
- off_linktype = 24;
- off_nl = 32; /* 802.11+802.2+SNAP */
- off_nl_nosnap = 27; /* 802.11+802.2 */
- return;
-
- case DLT_ATM_RFC1483:
- case DLT_ATM_CLIP: /* Linux ATM defines this */
- /*
- * assume routed, non-ISO PDUs
- * (i.e., LLC = 0xAA-AA-03, OUT = 0x00-00-00)
- *
- * XXX - what about ISO PDUs, e.g. CLNP, ISIS, ESIS,
- * or PPP with the PPP NLPID (e.g., PPPoA)? The
- * latter would presumably be treated the way PPPoE
- * should be, so you can do "pppoe and udp port 2049"
- * or "pppoa and tcp port 80" and have it check for
- * PPPo{A,E} and a PPP protocol of IP and....
- */
- off_linktype = 0;
- off_nl = 8; /* 802.2+SNAP */
- off_nl_nosnap = 3; /* 802.2 */
- return;
-
- case DLT_SUNATM:
- /*
- * Full Frontal ATM; you get AALn PDUs with an ATM
- * pseudo-header.
- */
- is_atm = 1;
- off_vpi = SUNATM_VPI_POS;
- off_vci = SUNATM_VCI_POS;
- off_proto = PROTO_POS;
- off_mac = -1; /* LLC-encapsulated, so no MAC-layer header */
- off_payload = SUNATM_PKT_BEGIN_POS;
- off_linktype = off_payload;
- off_nl = off_payload+8; /* 802.2+SNAP */
- off_nl_nosnap = off_payload+3; /* 802.2 */
- return;
-
- case DLT_RAW:
- off_linktype = -1;
- off_nl = 0;
- off_nl_nosnap = 0; /* no 802.2 LLC */
- return;
-
- case DLT_LINUX_SLL: /* fake header for Linux cooked socket */
- off_linktype = 14;
- off_nl = 16;
- off_nl_nosnap = 16; /* no 802.2 LLC */
- return;
-
- case DLT_LTALK:
- /*
- * LocalTalk does have a 1-byte type field in the LLAP header,
- * but really it just indicates whether there is a "short" or
- * "long" DDP packet following.
- */
- off_linktype = -1;
- off_nl = 0;
- off_nl_nosnap = 0; /* no 802.2 LLC */
- return;
-
- case DLT_IP_OVER_FC:
- /*
- * RFC 2625 IP-over-Fibre-Channel doesn't really have a
- * link-level type field. We set "off_linktype" to the
- * offset of the LLC header.
- *
- * To check for Ethernet types, we assume that SSAP = SNAP
- * is being used and pick out the encapsulated Ethernet type.
- * XXX - should we generate code to check for SNAP? RFC
- * 2625 says SNAP should be used.
- */
- off_linktype = 16;
- off_nl = 24; /* IPFC+802.2+SNAP */
- off_nl_nosnap = 19; /* IPFC+802.2 */
- return;
-
- case DLT_FRELAY:
- /*
- * XXX - we should set this to handle SNAP-encapsulated
- * frames (NLPID of 0x80).
- */
- off_linktype = -1;
- off_nl = 0;
- off_nl_nosnap = 0; /* no 802.2 LLC */
- return;
-
- /*
- * the only BPF-interesting FRF.16 frames are non-control frames;
- * Frame Relay has a variable length link-layer
- * so lets start with offset 4 for now and increments later on (FIXME);
- */
- case DLT_MFR:
- off_linktype = -1;
- off_nl = 4;
- off_nl_nosnap = 0; /* XXX - for now -> no 802.2 LLC */
- return;
-
- case DLT_APPLE_IP_OVER_IEEE1394:
- off_linktype = 16;
- off_nl = 18;
- off_nl_nosnap = 18; /* no 802.2 LLC */
- return;
-
- case DLT_LINUX_IRDA:
- /*
- * Currently, only raw "link[N:M]" filtering is supported.
- */
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
-
- case DLT_DOCSIS:
- /*
- * Currently, only raw "link[N:M]" filtering is supported.
- */
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
-
- case DLT_SYMANTEC_FIREWALL:
- off_linktype = 6;
- off_nl = 44; /* Ethernet II */
- off_nl_nosnap = 44; /* XXX - what does it do with 802.3 packets? */
- return;
-
- case DLT_PFLOG:
- off_linktype = 0;
- /* XXX read this from pf.h? */
- off_nl = PFLOG_HDRLEN;
- off_nl_nosnap = PFLOG_HDRLEN; /* no 802.2 LLC */
- return;
-
- case DLT_JUNIPER_MFR:
- case DLT_JUNIPER_MLFR:
- case DLT_JUNIPER_MLPPP:
- case DLT_JUNIPER_PPP:
- case DLT_JUNIPER_CHDLC:
- case DLT_JUNIPER_FRELAY:
- off_linktype = 4;
- off_nl = 4;
- off_nl_nosnap = -1; /* no 802.2 LLC */
- return;
-
- case DLT_JUNIPER_ATM1:
- off_linktype = 4; /* in reality variable between 4-8 */
- off_nl = 4;
- off_nl_nosnap = 14;
- return;
-
- case DLT_JUNIPER_ATM2:
- off_linktype = 8; /* in reality variable between 8-12 */
- off_nl = 8;
- off_nl_nosnap = 18;
- return;
-
- /* frames captured on a Juniper PPPoE service PIC
- * contain raw ethernet frames */
- case DLT_JUNIPER_PPPOE:
- case DLT_JUNIPER_ETHER:
- off_linktype = 16;
- off_nl = 18; /* Ethernet II */
- off_nl_nosnap = 21; /* 802.3+802.2 */
- return;
-
- case DLT_JUNIPER_PPPOE_ATM:
- off_linktype = 4;
- off_nl = 6;
- off_nl_nosnap = -1; /* no 802.2 LLC */
- return;
-
- case DLT_JUNIPER_GGSN:
- off_linktype = 6;
- off_nl = 12;
- off_nl_nosnap = -1; /* no 802.2 LLC */
- return;
-
- case DLT_JUNIPER_ES:
- off_linktype = 6;
- off_nl = -1; /* not really a network layer but raw IP adresses */
- off_nl_nosnap = -1; /* no 802.2 LLC */
- return;
-
- case DLT_JUNIPER_MONITOR:
- off_linktype = 12;
- off_nl = 12; /* raw IP/IP6 header */
- off_nl_nosnap = -1; /* no 802.2 LLC */
- return;
-
- case DLT_JUNIPER_SERVICES:
- off_linktype = 12;
- off_nl = -1; /* L3 proto location dep. on cookie type */
- off_nl_nosnap = -1; /* no 802.2 LLC */
- return;
-
- case DLT_JUNIPER_VP:
- off_linktype = 18;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
-
- case DLT_MTP2:
- off_li = 2;
- off_sio = 3;
- off_opc = 4;
- off_dpc = 4;
- off_sls = 7;
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
-
- case DLT_MTP2_WITH_PHDR:
- off_li = 6;
- off_sio = 7;
- off_opc = 8;
- off_dpc = 8;
- off_sls = 11;
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
-
-#ifdef DLT_PFSYNC
- case DLT_PFSYNC:
- off_linktype = -1;
- off_nl = 4;
- off_nl_nosnap = 4;
- return;
-#endif
-
- case DLT_LINUX_LAPD:
- /*
- * Currently, only raw "link[N:M]" filtering is supported.
- */
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
-
- case DLT_USB:
- /*
- * Currently, only raw "link[N:M]" filtering is supported.
- */
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
-
- case DLT_BLUETOOTH_HCI_H4:
- /*
- * Currently, only raw "link[N:M]" filtering is supported.
- */
- off_linktype = -1;
- off_nl = -1;
- off_nl_nosnap = -1;
- return;
- }
- bpf_error("unknown data link type %d", linktype);
- /* NOTREACHED */
-}
-
-/*
- * Load a value relative to the beginning of the link-layer header.
- * The link-layer header doesn't necessarily begin at the beginning
- * of the packet data; there might be a variable-length prefix containing
- * radio information.
- */
-static struct slist *
-gen_load_llrel(offset, size)
- u_int offset, size;
-{
- struct slist *s, *s2;
-
- s = gen_llprefixlen();
-
- /*
- * If "s" is non-null, it has code to arrange that the X register
- * contains the length of the prefix preceding the link-layer
- * header.
- *
- * Otherwise, the length of the prefix preceding the link-layer
- * header is "off_ll".
- */
- if (s != NULL) {
- /*
- * There's a variable-length prefix preceding the
- * link-layer header. "s" points to a list of statements
- * that put the length of that prefix into the X register.
- * do an indirect load, to use the X register as an offset.
- */
- s2 = new_stmt(BPF_LD|BPF_IND|size);
- s2->s.k = offset;
- sappend(s, s2);
- } else {
- /*
- * There is no variable-length header preceding the
- * link-layer header; add in off_ll, which, if there's
- * a fixed-length header preceding the link-layer header,
- * is the length of that header.
- */
- s = new_stmt(BPF_LD|BPF_ABS|size);
- s->s.k = offset + off_ll;
- }
- return s;
-}
-
-
-/*
- * Load a value relative to the beginning of the specified header.
- */
-static struct slist *
-gen_load_a(offrel, offset, size)
- enum e_offrel offrel;
- u_int offset, size;
-{
- struct slist *s, *s2;
-
- switch (offrel) {
-
- case OR_PACKET:
- s = new_stmt(BPF_LD|BPF_ABS|size);
- s->s.k = offset;
- break;
-
- case OR_LINK:
- s = gen_load_llrel(offset, size);
- break;
-
- case OR_NET:
- s = gen_load_llrel(off_nl + offset, size);
- break;
-
- case OR_NET_NOSNAP:
- s = gen_load_llrel(off_nl_nosnap + offset, size);
- break;
-
- case OR_TRAN_IPV4:
- /*
- * Load the X register with the length of the IPv4 header
- * (plus the offset of the link-layer header, if it's
- * preceded by a variable-length header such as a radio
- * header), in bytes.
- */
- s = gen_loadx_iphdrlen();
-
- /*
- * Load the item at {offset of the link-layer header} +
- * {offset, relative to the start of the link-layer
- * header, of the IPv4 header} + {length of the IPv4 header} +
- * {specified offset}.
- *
- * (If the link-layer is variable-length, it's included
- * in the value in the X register, and off_ll is 0.)
- */
- s2 = new_stmt(BPF_LD|BPF_IND|size);
- s2->s.k = off_ll + off_nl + offset;
- sappend(s, s2);
- break;
-
- case OR_TRAN_IPV6:
- s = gen_load_llrel(off_nl + 40 + offset, size);
- break;
-
- default:
- abort();
- return NULL;
- }
- return s;
-}
-
-/*
- * Generate code to load into the X register the sum of the length of
- * the IPv4 header and any variable-length header preceding the link-layer
- * header.
- */
-static struct slist *
-gen_loadx_iphdrlen()
-{
- struct slist *s, *s2;
-
- s = gen_llprefixlen();
- if (s != NULL) {
- /*
- * There's a variable-length prefix preceding the
- * link-layer header. "s" points to a list of statements
- * that put the length of that prefix into the X register.
- * The 4*([k]&0xf) addressing mode can't be used, as we
- * don't have a constant offset, so we have to load the
- * value in question into the A register and add to it
- * the value from the X register.
- */
- s2 = new_stmt(BPF_LD|BPF_IND|BPF_B);
- s2->s.k = off_nl;
- sappend(s, s2);
- s2 = new_stmt(BPF_ALU|BPF_AND|BPF_K);
- s2->s.k = 0xf;
- sappend(s, s2);
- s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
- s2->s.k = 2;
- sappend(s, s2);
-
- /*
- * The A register now contains the length of the
- * IP header. We need to add to it the length
- * of the prefix preceding the link-layer
- * header, which is still in the X register, and
- * move the result into the X register.
- */
- sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
- sappend(s, new_stmt(BPF_MISC|BPF_TAX));
- } else {
- /*
- * There is no variable-length header preceding the
- * link-layer header; add in off_ll, which, if there's
- * a fixed-length header preceding the link-layer header,
- * is the length of that header.
- */
- s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
- s->s.k = off_ll + off_nl;
- }
- return s;
-}
-
-static struct block *
-gen_uncond(rsense)
- int rsense;
-{
- struct block *b;
- struct slist *s;
-
- s = new_stmt(BPF_LD|BPF_IMM);
- s->s.k = !rsense;
- b = new_block(JMP(BPF_JEQ));
- b->stmts = s;
-
- return b;
-}
-
-static inline struct block *
-gen_true()
-{
- return gen_uncond(1);
-}
-
-static inline struct block *
-gen_false()
-{
- return gen_uncond(0);
-}
-
-/*
- * Byte-swap a 32-bit number.
- * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
- * big-endian platforms.)
- */
-#define SWAPLONG(y) \
-((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
-
-/*
- * Generate code to match a particular packet type.
- *
- * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
- * value, if <= ETHERMTU. We use that to determine whether to
- * match the type/length field or to check the type/length field for
- * a value <= ETHERMTU to see whether it's a type field and then do
- * the appropriate test.
- */
-static struct block *
-gen_ether_linktype(proto)
- register int proto;
-{
- struct block *b0, *b1;
-
- switch (proto) {
-
- case LLCSAP_ISONS:
- case LLCSAP_IP:
- case LLCSAP_NETBEUI:
- /*
- * OSI protocols and NetBEUI always use 802.2 encapsulation,
- * so we check the DSAP and SSAP.
- *
- * LLCSAP_IP checks for IP-over-802.2, rather
- * than IP-over-Ethernet or IP-over-SNAP.
- *
- * XXX - should we check both the DSAP and the
- * SSAP, like this, or should we check just the
- * DSAP, as we do for other types <= ETHERMTU
- * (i.e., other SAP values)?
- */
- b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
- b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H, (bpf_int32)
- ((proto << 8) | proto));
- gen_and(b0, b1);
- return b1;
-
- case LLCSAP_IPX:
- /*
- * Check for;
- *
- * Ethernet_II frames, which are Ethernet
- * frames with a frame type of ETHERTYPE_IPX;
- *
- * Ethernet_802.3 frames, which are 802.3
- * frames (i.e., the type/length field is
- * a length field, <= ETHERMTU, rather than
- * a type field) with the first two bytes
- * after the Ethernet/802.3 header being
- * 0xFFFF;
- *
- * Ethernet_802.2 frames, which are 802.3
- * frames with an 802.2 LLC header and
- * with the IPX LSAP as the DSAP in the LLC
- * header;
- *
- * Ethernet_SNAP frames, which are 802.3
- * frames with an LLC header and a SNAP
- * header and with an OUI of 0x000000
- * (encapsulated Ethernet) and a protocol
- * ID of ETHERTYPE_IPX in the SNAP header.
- *
- * XXX - should we generate the same code both
- * for tests for LLCSAP_IPX and for ETHERTYPE_IPX?
- */
-
- /*
- * This generates code to check both for the
- * IPX LSAP (Ethernet_802.2) and for Ethernet_802.3.
- */
- b0 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
- (bpf_int32)LLCSAP_IPX);
- b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H,
- (bpf_int32)0xFFFF);
- gen_or(b0, b1);
-
- /*
- * Now we add code to check for SNAP frames with
- * ETHERTYPE_IPX, i.e. Ethernet_SNAP.
- */
- b0 = gen_snap(0x000000, ETHERTYPE_IPX, 14);
- gen_or(b0, b1);
-
- /*
- * Now we generate code to check for 802.3
- * frames in general.
- */
- b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
-
- /*
- * Now add the check for 802.3 frames before the
- * check for Ethernet_802.2 and Ethernet_802.3,
- * as those checks should only be done on 802.3
- * frames, not on Ethernet frames.
- */
- gen_and(b0, b1);
-
- /*
- * Now add the check for Ethernet_II frames, and
- * do that before checking for the other frame
- * types.
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
- (bpf_int32)ETHERTYPE_IPX);
- gen_or(b0, b1);
- return b1;
-
- case ETHERTYPE_ATALK:
- case ETHERTYPE_AARP:
- /*
- * EtherTalk (AppleTalk protocols on Ethernet link
- * layer) may use 802.2 encapsulation.
- */
-
- /*
- * Check for 802.2 encapsulation (EtherTalk phase 2?);
- * we check for an Ethernet type field less than
- * 1500, which means it's an 802.3 length field.
- */
- b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
-
- /*
- * 802.2-encapsulated ETHERTYPE_ATALK packets are
- * SNAP packets with an organization code of
- * 0x080007 (Apple, for Appletalk) and a protocol
- * type of ETHERTYPE_ATALK (Appletalk).
- *
- * 802.2-encapsulated ETHERTYPE_AARP packets are
- * SNAP packets with an organization code of
- * 0x000000 (encapsulated Ethernet) and a protocol
- * type of ETHERTYPE_AARP (Appletalk ARP).
- */
- if (proto == ETHERTYPE_ATALK)
- b1 = gen_snap(0x080007, ETHERTYPE_ATALK, 14);
- else /* proto == ETHERTYPE_AARP */
- b1 = gen_snap(0x000000, ETHERTYPE_AARP, 14);
- gen_and(b0, b1);
-
- /*
- * Check for Ethernet encapsulation (Ethertalk
- * phase 1?); we just check for the Ethernet
- * protocol type.
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
-
- gen_or(b0, b1);
- return b1;
-
- default:
- if (proto <= ETHERMTU) {
- /*
- * This is an LLC SAP value, so the frames
- * that match would be 802.2 frames.
- * Check that the frame is an 802.2 frame
- * (i.e., that the length/type field is
- * a length field, <= ETHERMTU) and
- * then check the DSAP.
- */
- b0 = gen_cmp_gt(OR_LINK, off_linktype, BPF_H, ETHERMTU);
- gen_not(b0);
- b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
- (bpf_int32)proto);
- gen_and(b0, b1);
- return b1;
- } else {
- /*
- * This is an Ethernet type, so compare
- * the length/type field with it (if
- * the frame is an 802.2 frame, the length
- * field will be <= ETHERMTU, and, as
- * "proto" is > ETHERMTU, this test
- * will fail and the frame won't match,
- * which is what we want).
- */
- return gen_cmp(OR_LINK, off_linktype, BPF_H,
- (bpf_int32)proto);
- }
- }
-}
-
-/*
- * Generate code to match a particular packet type.
- *
- * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
- * value, if <= ETHERMTU. We use that to determine whether to
- * match the type field or to check the type field for the special
- * LINUX_SLL_P_802_2 value and then do the appropriate test.
- */
-static struct block *
-gen_linux_sll_linktype(proto)
- register int proto;
-{
- struct block *b0, *b1;
-
- switch (proto) {
-
- case LLCSAP_ISONS:
- case LLCSAP_IP:
- case LLCSAP_NETBEUI:
- /*
- * OSI protocols and NetBEUI always use 802.2 encapsulation,
- * so we check the DSAP and SSAP.
- *
- * LLCSAP_IP checks for IP-over-802.2, rather
- * than IP-over-Ethernet or IP-over-SNAP.
- *
- * XXX - should we check both the DSAP and the
- * SSAP, like this, or should we check just the
- * DSAP, as we do for other types <= ETHERMTU
- * (i.e., other SAP values)?
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
- b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_H, (bpf_int32)
- ((proto << 8) | proto));
- gen_and(b0, b1);
- return b1;
-
- case LLCSAP_IPX:
- /*
- * Ethernet_II frames, which are Ethernet
- * frames with a frame type of ETHERTYPE_IPX;
- *
- * Ethernet_802.3 frames, which have a frame
- * type of LINUX_SLL_P_802_3;
- *
- * Ethernet_802.2 frames, which are 802.3
- * frames with an 802.2 LLC header (i.e, have
- * a frame type of LINUX_SLL_P_802_2) and
- * with the IPX LSAP as the DSAP in the LLC
- * header;
- *
- * Ethernet_SNAP frames, which are 802.3
- * frames with an LLC header and a SNAP
- * header and with an OUI of 0x000000
- * (encapsulated Ethernet) and a protocol
- * ID of ETHERTYPE_IPX in the SNAP header.
- *
- * First, do the checks on LINUX_SLL_P_802_2
- * frames; generate the check for either
- * Ethernet_802.2 or Ethernet_SNAP frames, and
- * then put a check for LINUX_SLL_P_802_2 frames
- * before it.
- */
- b0 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
- (bpf_int32)LLCSAP_IPX);
- b1 = gen_snap(0x000000, ETHERTYPE_IPX,
- off_linktype + 2);
- gen_or(b0, b1);
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
- gen_and(b0, b1);
-
- /*
- * Now check for 802.3 frames and OR that with
- * the previous test.
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_3);
- gen_or(b0, b1);
-
- /*
- * Now add the check for Ethernet_II frames, and
- * do that before checking for the other frame
- * types.
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
- (bpf_int32)ETHERTYPE_IPX);
- gen_or(b0, b1);
- return b1;
-
- case ETHERTYPE_ATALK:
- case ETHERTYPE_AARP:
- /*
- * EtherTalk (AppleTalk protocols on Ethernet link
- * layer) may use 802.2 encapsulation.
- */
-
- /*
- * Check for 802.2 encapsulation (EtherTalk phase 2?);
- * we check for the 802.2 protocol type in the
- * "Ethernet type" field.
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, LINUX_SLL_P_802_2);
-
- /*
- * 802.2-encapsulated ETHERTYPE_ATALK packets are
- * SNAP packets with an organization code of
- * 0x080007 (Apple, for Appletalk) and a protocol
- * type of ETHERTYPE_ATALK (Appletalk).
- *
- * 802.2-encapsulated ETHERTYPE_AARP packets are
- * SNAP packets with an organization code of
- * 0x000000 (encapsulated Ethernet) and a protocol
- * type of ETHERTYPE_AARP (Appletalk ARP).
- */
- if (proto == ETHERTYPE_ATALK)
- b1 = gen_snap(0x080007, ETHERTYPE_ATALK,
- off_linktype + 2);
- else /* proto == ETHERTYPE_AARP */
- b1 = gen_snap(0x000000, ETHERTYPE_AARP,
- off_linktype + 2);
- gen_and(b0, b1);
-
- /*
- * Check for Ethernet encapsulation (Ethertalk
- * phase 1?); we just check for the Ethernet
- * protocol type.
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
-
- gen_or(b0, b1);
- return b1;
-
- default:
- if (proto <= ETHERMTU) {
- /*
- * This is an LLC SAP value, so the frames
- * that match would be 802.2 frames.
- * Check for the 802.2 protocol type
- * in the "Ethernet type" field, and
- * then check the DSAP.
- */
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
- LINUX_SLL_P_802_2);
- b1 = gen_cmp(OR_LINK, off_linktype + 2, BPF_B,
- (bpf_int32)proto);
- gen_and(b0, b1);
- return b1;
- } else {
- /*
- * This is an Ethernet type, so compare
- * the length/type field with it (if
- * the frame is an 802.2 frame, the length
- * field will be <= ETHERMTU, and, as
- * "proto" is > ETHERMTU, this test
- * will fail and the frame won't match,
- * which is what we want).
- */
- return gen_cmp(OR_LINK, off_linktype, BPF_H,
- (bpf_int32)proto);
- }
- }
-}
-
-static void
-insert_radiotap_load_llprefixlen(b)
- struct block *b;
-{
- struct slist *s1, *s2;
-
- /*
- * Prepend to the statements in this block code to load the
- * length of the radiotap header into the register assigned
- * to hold that length, if one has been assigned.
- */
- if (reg_ll_size != -1) {
- /*
- * The 2 bytes at offsets of 2 and 3 from the beginning
- * of the radiotap header are the length of the radiotap
- * header; unfortunately, it's little-endian, so we have
- * to load it a byte at a time and construct the value.
- */
-
- /*
- * Load the high-order byte, at an offset of 3, shift it
- * left a byte, and put the result in the X register.
- */
- s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
- s1->s.k = 3;
- s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
- sappend(s1, s2);
- s2->s.k = 8;
- s2 = new_stmt(BPF_MISC|BPF_TAX);
- sappend(s1, s2);
-
- /*
- * Load the next byte, at an offset of 2, and OR the
- * value from the X register into it.
- */
- s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
- sappend(s1, s2);
- s2->s.k = 2;
- s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
- sappend(s1, s2);
-
- /*
- * Now allocate a register to hold that value and store
- * it.
- */
- s2 = new_stmt(BPF_ST);
- s2->s.k = reg_ll_size;
- sappend(s1, s2);
-
- /*
- * Now move it into the X register.
- */
- s2 = new_stmt(BPF_MISC|BPF_TAX);
- sappend(s1, s2);
-
- /*
- * Now append all the existing statements in this
- * block to these statements.
- */
- sappend(s1, b->stmts);
- b->stmts = s1;
- }
-}
-
-/*
- * At the moment we treat PPI as normal Radiotap encoded
- * packets. The difference is in the function that generates
- * the code at the beginning to compute the header length.
- * Since this code generator of PPI supports bare 802.11
- * encapsulation only (i.e. the encapsulated DLT should be
- * DLT_IEEE802_11) we generate code to check for this too.
- */
-static void
-insert_ppi_load_llprefixlen(b)
- struct block *b;
-{
- struct slist *s1, *s2;
-
- /*
- * Prepend to the statements in this block code to load the
- * length of the radiotap header into the register assigned
- * to hold that length, if one has been assigned.
- */
- if (reg_ll_size != -1) {
- /*
- * The 2 bytes at offsets of 2 and 3 from the beginning
- * of the radiotap header are the length of the radiotap
- * header; unfortunately, it's little-endian, so we have
- * to load it a byte at a time and construct the value.
- */
-
- /*
- * Load the high-order byte, at an offset of 3, shift it
- * left a byte, and put the result in the X register.
- */
- s1 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
- s1->s.k = 3;
- s2 = new_stmt(BPF_ALU|BPF_LSH|BPF_K);
- sappend(s1, s2);
- s2->s.k = 8;
- s2 = new_stmt(BPF_MISC|BPF_TAX);
- sappend(s1, s2);
-
- /*
- * Load the next byte, at an offset of 2, and OR the
- * value from the X register into it.
- */
- s2 = new_stmt(BPF_LD|BPF_B|BPF_ABS);
- sappend(s1, s2);
- s2->s.k = 2;
- s2 = new_stmt(BPF_ALU|BPF_OR|BPF_X);
- sappend(s1, s2);
-
- /*
- * Now allocate a register to hold that value and store
- * it.
- */
- s2 = new_stmt(BPF_ST);
- s2->s.k = reg_ll_size;
- sappend(s1, s2);
-
- /*
- * Now move it into the X register.
- */
- s2 = new_stmt(BPF_MISC|BPF_TAX);
- sappend(s1, s2);
-
- /*
- * Now append all the existing statements in this
- * block to these statements.
- */
- sappend(s1, b->stmts);
- b->stmts = s1;
-
- }
-}
-
-static struct block *
-gen_ppi_dlt_check(void)
-{
- struct slist *s_load_dlt;
- struct block *b;
-
- if (linktype == DLT_PPI)
- {
- /* Create the statements that check for the DLT
- */
- s_load_dlt = new_stmt(BPF_LD|BPF_W|BPF_ABS);
- s_load_dlt->s.k = 4;
-
- b = new_block(JMP(BPF_JEQ));
-
- b->stmts = s_load_dlt;
- b->s.k = SWAPLONG(DLT_IEEE802_11);
- }
- else
- {
- b = NULL;
- }
-
- return b;
-}
-
-static void
-insert_load_llprefixlen(b)
- struct block *b;
-{
- switch (linktype) {
-
- /*
- * At the moment we treat PPI as normal Radiotap encoded
- * packets. The difference is in the function that generates
- * the code at the beginning to compute the header length.
- * Since this code generator of PPI supports bare 802.11
- * encapsulation only (i.e. the encapsulated DLT should be
- * DLT_IEEE802_11) we generate code to check for this too.
- */
- case DLT_PPI:
- insert_ppi_load_llprefixlen(b);
- break;
-
- case DLT_IEEE802_11_RADIO:
- insert_radiotap_load_llprefixlen(b);
- break;
- }
-}
-
-
-static struct slist *
-gen_radiotap_llprefixlen(void)
-{
- struct slist *s;
-
- if (reg_ll_size == -1) {
- /*
- * We haven't yet assigned a register for the length
- * of the radiotap header; allocate one.
- */
- reg_ll_size = alloc_reg();
- }
-
- /*
- * Load the register containing the radiotap length
- * into the X register.
- */
- s = new_stmt(BPF_LDX|BPF_MEM);
- s->s.k = reg_ll_size;
- return s;
-}
-
-/*
- * At the moment we treat PPI as normal Radiotap encoded
- * packets. The difference is in the function that generates
- * the code at the beginning to compute the header length.
- * Since this code generator of PPI supports bare 802.11
- * encapsulation only (i.e. the encapsulated DLT should be
- * DLT_IEEE802_11) we generate code to check for this too.
- */
-static struct slist *
-gen_ppi_llprefixlen(void)
-{
- struct slist *s;
-
- if (reg_ll_size == -1) {
- /*
- * We haven't yet assigned a register for the length
- * of the radiotap header; allocate one.
- */
- reg_ll_size = alloc_reg();
- }
-
- /*
- * Load the register containing the radiotap length
- * into the X register.
- */
- s = new_stmt(BPF_LDX|BPF_MEM);
- s->s.k = reg_ll_size;
- return s;
-}
-
-
-
-/*
- * Generate code to compute the link-layer header length, if necessary,
- * putting it into the X register, and to return either a pointer to a
- * "struct slist" for the list of statements in that code, or NULL if
- * no code is necessary.
- */
-static struct slist *
-gen_llprefixlen(void)
-{
- switch (linktype) {
-
- case DLT_PPI:
- return gen_ppi_llprefixlen();
-
-
- case DLT_IEEE802_11_RADIO:
- return gen_radiotap_llprefixlen();
-
- default:
- return NULL;
- }
-}
-
-/*
- * Generate code to match a particular packet type by matching the
- * link-layer type field or fields in the 802.2 LLC header.
- *
- * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
- * value, if <= ETHERMTU.
- */
-static struct block *
-gen_linktype(proto)
- register int proto;
-{
- struct block *b0, *b1, *b2;
-
- /* are we checking MPLS-encapsulated packets? */
- if (label_stack_depth > 0) {
- switch (proto) {
- case ETHERTYPE_IP:
- case PPP_IP:
- /* FIXME add other L3 proto IDs */
- return gen_mpls_linktype(Q_IP);
-
- case ETHERTYPE_IPV6:
- case PPP_IPV6:
- /* FIXME add other L3 proto IDs */
- return gen_mpls_linktype(Q_IPV6);
-
- default:
- bpf_error("unsupported protocol over mpls");
- /* NOTREACHED */
- }
- }
-
- switch (linktype) {
-
- case DLT_EN10MB:
- return gen_ether_linktype(proto);
- /*NOTREACHED*/
- break;
-
- case DLT_C_HDLC:
- switch (proto) {
-
- case LLCSAP_ISONS:
- proto = (proto << 8 | LLCSAP_ISONS);
- /* fall through */
-
- default:
- return gen_cmp(OR_LINK, off_linktype, BPF_H,
- (bpf_int32)proto);
- /*NOTREACHED*/
- break;
- }
- break;
-
- case DLT_PPI:
- case DLT_FDDI:
- case DLT_IEEE802:
- case DLT_IEEE802_11:
- case DLT_IEEE802_11_RADIO_AVS:
- case DLT_IEEE802_11_RADIO:
- case DLT_PRISM_HEADER:
- case DLT_ATM_RFC1483:
- case DLT_ATM_CLIP:
- case DLT_IP_OVER_FC:
- return gen_llc_linktype(proto);
- /*NOTREACHED*/
- break;
-
- case DLT_SUNATM:
- /*
- * If "is_lane" is set, check for a LANE-encapsulated
- * version of this protocol, otherwise check for an
- * LLC-encapsulated version of this protocol.
- *
- * We assume LANE means Ethernet, not Token Ring.
- */
- if (is_lane) {
- /*
- * Check that the packet doesn't begin with an
- * LE Control marker. (We've already generated
- * a test for LANE.)
- */
- b0 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
- 0xFF00);
- gen_not(b0);
-
- /*
- * Now generate an Ethernet test.
- */
- b1 = gen_ether_linktype(proto);
- gen_and(b0, b1);
- return b1;
- } else {
- /*
- * Check for LLC encapsulation and then check the
- * protocol.
- */
- b0 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
- b1 = gen_llc_linktype(proto);
- gen_and(b0, b1);
- return b1;
- }
- /*NOTREACHED*/
- break;
-
- case DLT_LINUX_SLL:
- return gen_linux_sll_linktype(proto);
- /*NOTREACHED*/
- break;
-
- case DLT_SLIP:
- case DLT_SLIP_BSDOS:
- case DLT_RAW:
- /*
- * These types don't provide any type field; packets
- * are always IPv4 or IPv6.
- *
- * XXX - for IPv4, check for a version number of 4, and,
- * for IPv6, check for a version number of 6?
- */
- switch (proto) {
-
- case ETHERTYPE_IP:
- /* Check for a version number of 4. */
- return gen_mcmp(OR_LINK, 0, BPF_B, 0x40, 0xF0);
-#ifdef INET6
- case ETHERTYPE_IPV6:
- /* Check for a version number of 6. */
- return gen_mcmp(OR_LINK, 0, BPF_B, 0x60, 0xF0);
-#endif
-
- default:
- return gen_false(); /* always false */
- }
- /*NOTREACHED*/
- break;
-
- case DLT_PPP:
- case DLT_PPP_PPPD:
- case DLT_PPP_SERIAL:
- case DLT_PPP_ETHER:
- /*
- * We use Ethernet protocol types inside libpcap;
- * map them to the corresponding PPP protocol types.
- */
- switch (proto) {
-
- case ETHERTYPE_IP:
- proto = PPP_IP;
- break;
-
-#ifdef INET6
- case ETHERTYPE_IPV6:
- proto = PPP_IPV6;
- break;
-#endif
-
- case ETHERTYPE_DN:
- proto = PPP_DECNET;
- break;
-
- case ETHERTYPE_ATALK:
- proto = PPP_APPLE;
- break;
-
- case ETHERTYPE_NS:
- proto = PPP_NS;
- break;
-
- case LLCSAP_ISONS:
- proto = PPP_OSI;
- break;
-
- case LLCSAP_8021D:
- /*
- * I'm assuming the "Bridging PDU"s that go
- * over PPP are Spanning Tree Protocol
- * Bridging PDUs.
- */
- proto = PPP_BRPDU;
- break;
-
- case LLCSAP_IPX:
- proto = PPP_IPX;
- break;
- }
- break;
-
- case DLT_PPP_BSDOS:
- /*
- * We use Ethernet protocol types inside libpcap;
- * map them to the corresponding PPP protocol types.
- */
- switch (proto) {
-
- case ETHERTYPE_IP:
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_IP);
- b1 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJC);
- gen_or(b0, b1);
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_H, PPP_VJNC);
- gen_or(b1, b0);
- return b0;
-
-#ifdef INET6
- case ETHERTYPE_IPV6:
- proto = PPP_IPV6;
- /* more to go? */
- break;
-#endif
-
- case ETHERTYPE_DN:
- proto = PPP_DECNET;
- break;
-
- case ETHERTYPE_ATALK:
- proto = PPP_APPLE;
- break;
-
- case ETHERTYPE_NS:
- proto = PPP_NS;
- break;
-
- case LLCSAP_ISONS:
- proto = PPP_OSI;
- break;
-
- case LLCSAP_8021D:
- /*
- * I'm assuming the "Bridging PDU"s that go
- * over PPP are Spanning Tree Protocol
- * Bridging PDUs.
- */
- proto = PPP_BRPDU;
- break;
-
- case LLCSAP_IPX:
- proto = PPP_IPX;
- break;
- }
- break;
-
- case DLT_NULL:
- case DLT_LOOP:
- case DLT_ENC:
- /*
- * For DLT_NULL, the link-layer header is a 32-bit
- * word containing an AF_ value in *host* byte order,
- * and for DLT_ENC, the link-layer header begins
- * with a 32-bit work containing an AF_ value in
- * host byte order.
- *
- * In addition, if we're reading a saved capture file,
- * the host byte order in the capture may not be the
- * same as the host byte order on this machine.
- *
- * For DLT_LOOP, the link-layer header is a 32-bit
- * word containing an AF_ value in *network* byte order.
- *
- * XXX - AF_ values may, unfortunately, be platform-
- * dependent; for example, FreeBSD's AF_INET6 is 24
- * whilst NetBSD's and OpenBSD's is 26.
- *
- * This means that, when reading a capture file, just
- * checking for our AF_INET6 value won't work if the
- * capture file came from another OS.
- */
- switch (proto) {
-
- case ETHERTYPE_IP:
- proto = AF_INET;
- break;
-
-#ifdef INET6
- case ETHERTYPE_IPV6:
- proto = AF_INET6;
- break;
-#endif
-
- default:
- /*
- * Not a type on which we support filtering.
- * XXX - support those that have AF_ values
- * #defined on this platform, at least?
- */
- return gen_false();
- }
-
- if (linktype == DLT_NULL || linktype == DLT_ENC) {
- /*
- * The AF_ value is in host byte order, but
- * the BPF interpreter will convert it to
- * network byte order.
- *
- * If this is a save file, and it's from a
- * machine with the opposite byte order to
- * ours, we byte-swap the AF_ value.
- *
- * Then we run it through "htonl()", and
- * generate code to compare against the result.
- */
- if (bpf_pcap->sf.rfile != NULL &&
- bpf_pcap->sf.swapped)
- proto = SWAPLONG(proto);
- proto = htonl(proto);
- }
- return (gen_cmp(OR_LINK, 0, BPF_W, (bpf_int32)proto));
-
- case DLT_PFLOG:
- /*
- * af field is host byte order in contrast to the rest of
- * the packet.
- */
- if (proto == ETHERTYPE_IP)
- return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
- BPF_B, (bpf_int32)AF_INET));
-#ifdef INET6
- else if (proto == ETHERTYPE_IPV6)
- return (gen_cmp(OR_LINK, offsetof(struct pfloghdr, af),
- BPF_B, (bpf_int32)AF_INET6));
-#endif /* INET6 */
- else
- return gen_false();
- /*NOTREACHED*/
- break;
-
- case DLT_ARCNET:
- case DLT_ARCNET_LINUX:
- /*
- * XXX should we check for first fragment if the protocol
- * uses PHDS?
- */
- switch (proto) {
-
- default:
- return gen_false();
-
-#ifdef INET6
- case ETHERTYPE_IPV6:
- return (gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)ARCTYPE_INET6));
-#endif /* INET6 */
-
- case ETHERTYPE_IP:
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)ARCTYPE_IP);
- b1 = gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)ARCTYPE_IP_OLD);
- gen_or(b0, b1);
- return (b1);
-
- case ETHERTYPE_ARP:
- b0 = gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)ARCTYPE_ARP);
- b1 = gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)ARCTYPE_ARP_OLD);
- gen_or(b0, b1);
- return (b1);
-
- case ETHERTYPE_REVARP:
- return (gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)ARCTYPE_REVARP));
-
- case ETHERTYPE_ATALK:
- return (gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)ARCTYPE_ATALK));
- }
- /*NOTREACHED*/
- break;
-
- case DLT_LTALK:
- switch (proto) {
- case ETHERTYPE_ATALK:
- return gen_true();
- default:
- return gen_false();
- }
- /*NOTREACHED*/
- break;
-
- case DLT_FRELAY:
- /*
- * XXX - assumes a 2-byte Frame Relay header with
- * DLCI and flags. What if the address is longer?
- */
- switch (proto) {
-
- case ETHERTYPE_IP:
- /*
- * Check for the special NLPID for IP.
- */
- return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0xcc);
-
-#ifdef INET6
- case ETHERTYPE_IPV6:
- /*
- * Check for the special NLPID for IPv6.
- */
- return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | 0x8e);
-#endif
-
- case LLCSAP_ISONS:
- /*
- * Check for several OSI protocols.
- *
- * Frame Relay packets typically have an OSI
- * NLPID at the beginning; we check for each
- * of them.
- *
- * What we check for is the NLPID and a frame
- * control field of UI, i.e. 0x03 followed
- * by the NLPID.
- */
- b0 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO8473_CLNP);
- b1 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO9542_ESIS);
- b2 = gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | ISO10589_ISIS);
- gen_or(b1, b2);
- gen_or(b0, b2);
- return b2;
-
- default:
- return gen_false();
- }
- /*NOTREACHED*/
- break;
-
- case DLT_JUNIPER_MFR:
- case DLT_JUNIPER_MLFR:
- case DLT_JUNIPER_MLPPP:
- case DLT_JUNIPER_ATM1:
- case DLT_JUNIPER_ATM2:
- case DLT_JUNIPER_PPPOE:
- case DLT_JUNIPER_PPPOE_ATM:
- case DLT_JUNIPER_GGSN:
- case DLT_JUNIPER_ES:
- case DLT_JUNIPER_MONITOR:
- case DLT_JUNIPER_SERVICES:
- case DLT_JUNIPER_ETHER:
- case DLT_JUNIPER_PPP:
- case DLT_JUNIPER_FRELAY:
- case DLT_JUNIPER_CHDLC:
- case DLT_JUNIPER_VP:
- /* just lets verify the magic number for now -
- * on ATM we may have up to 6 different encapsulations on the wire
- * and need a lot of heuristics to figure out that the payload
- * might be;
- *
- * FIXME encapsulation specific BPF_ filters
- */
- return gen_mcmp(OR_LINK, 0, BPF_W, 0x4d474300, 0xffffff00); /* compare the magic number */
-
- case DLT_LINUX_IRDA:
- bpf_error("IrDA link-layer type filtering not implemented");
-
- case DLT_DOCSIS:
- bpf_error("DOCSIS link-layer type filtering not implemented");
-
- case DLT_LINUX_LAPD:
- bpf_error("LAPD link-layer type filtering not implemented");
- }
-
- /*
- * All the types that have no encapsulation should either be
- * handled as DLT_SLIP, DLT_SLIP_BSDOS, and DLT_RAW are, if
- * all packets are IP packets, or should be handled in some
- * special case, if none of them are (if some are and some
- * aren't, the lack of encapsulation is a problem, as we'd
- * have to find some other way of determining the packet type).
- *
- * Therefore, if "off_linktype" is -1, there's an error.
- */
- if (off_linktype == (u_int)-1)
- abort();
-
- /*
- * Any type not handled above should always have an Ethernet
- * type at an offset of "off_linktype". (PPP is partially
- * handled above - the protocol type is mapped from the
- * Ethernet and LLC types we use internally to the corresponding
- * PPP type - but the PPP type is always specified by a value
- * at "off_linktype", so we don't have to do the code generation
- * above.)
- */
- return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_int32)proto);
-}
-
-/*
- * Check for an LLC SNAP packet with a given organization code and
- * protocol type; we check the entire contents of the 802.2 LLC and
- * snap headers, checking for DSAP and SSAP of SNAP and a control
- * field of 0x03 in the LLC header, and for the specified organization
- * code and protocol type in the SNAP header.
- */
-static struct block *
-gen_snap(orgcode, ptype, offset)
- bpf_u_int32 orgcode;
- bpf_u_int32 ptype;
- u_int offset;
-{
- u_char snapblock[8];
-
- snapblock[0] = LLCSAP_SNAP; /* DSAP = SNAP */
- snapblock[1] = LLCSAP_SNAP; /* SSAP = SNAP */
- snapblock[2] = 0x03; /* control = UI */
- snapblock[3] = (orgcode >> 16); /* upper 8 bits of organization code */
- snapblock[4] = (orgcode >> 8); /* middle 8 bits of organization code */
- snapblock[5] = (orgcode >> 0); /* lower 8 bits of organization code */
- snapblock[6] = (ptype >> 8); /* upper 8 bits of protocol type */
- snapblock[7] = (ptype >> 0); /* lower 8 bits of protocol type */
- return gen_bcmp(OR_LINK, offset, 8, snapblock);
-}
-
-/*
- * Generate code to match a particular packet type, for link-layer types
- * using 802.2 LLC headers.
- *
- * This is *NOT* used for Ethernet; "gen_ether_linktype()" is used
- * for that - it handles the D/I/X Ethernet vs. 802.3+802.2 issues.
- *
- * "proto" is an Ethernet type value, if > ETHERMTU, or an LLC SAP
- * value, if <= ETHERMTU. We use that to determine whether to
- * match the DSAP or both DSAP and LSAP or to check the OUI and
- * protocol ID in a SNAP header.
- */
-static struct block *
-gen_llc_linktype(proto)
- int proto;
-{
- /*
- * XXX - handle token-ring variable-length header.
- */
- switch (proto) {
-
- case LLCSAP_IP:
- case LLCSAP_ISONS:
- case LLCSAP_NETBEUI:
- /*
- * XXX - should we check both the DSAP and the
- * SSAP, like this, or should we check just the
- * DSAP, as we do for other types <= ETHERMTU
- * (i.e., other SAP values)?
- */
- return gen_cmp(OR_LINK, off_linktype, BPF_H, (bpf_u_int32)
- ((proto << 8) | proto));
-
- case LLCSAP_IPX:
- /*
- * XXX - are there ever SNAP frames for IPX on
- * non-Ethernet 802.x networks?
- */
- return gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)LLCSAP_IPX);
-
- case ETHERTYPE_ATALK:
- /*
- * 802.2-encapsulated ETHERTYPE_ATALK packets are
- * SNAP packets with an organization code of
- * 0x080007 (Apple, for Appletalk) and a protocol
- * type of ETHERTYPE_ATALK (Appletalk).
- *
- * XXX - check for an organization code of
- * encapsulated Ethernet as well?
- */
- return gen_snap(0x080007, ETHERTYPE_ATALK, off_linktype);
-
- default:
- /*
- * XXX - we don't have to check for IPX 802.3
- * here, but should we check for the IPX Ethertype?
- */
- if (proto <= ETHERMTU) {
- /*
- * This is an LLC SAP value, so check
- * the DSAP.
- */
- return gen_cmp(OR_LINK, off_linktype, BPF_B,
- (bpf_int32)proto);
- } else {
- /*
- * This is an Ethernet type; we assume that it's
- * unlikely that it'll appear in the right place
- * at random, and therefore check only the
- * location that would hold the Ethernet type
- * in a SNAP frame with an organization code of
- * 0x000000 (encapsulated Ethernet).
- *
- * XXX - if we were to check for the SNAP DSAP and
- * LSAP, as per XXX, and were also to check for an
- * organization code of 0x000000 (encapsulated
- * Ethernet), we'd do
- *
- * return gen_snap(0x000000, proto,
- * off_linktype);
- *
- * here; for now, we don't, as per the above.
- * I don't know whether it's worth the extra CPU
- * time to do the right check or not.
- */
- return gen_cmp(OR_LINK, off_linktype+6, BPF_H,
- (bpf_int32)proto);
- }
- }
-}
-
-static struct block *
-gen_hostop(addr, mask, dir, proto, src_off, dst_off)
- bpf_u_int32 addr;
- bpf_u_int32 mask;
- int dir, proto;
- u_int src_off, dst_off;
-{
- struct block *b0, *b1;
- u_int offset;
-
- switch (dir) {
-
- case Q_SRC:
- offset = src_off;
- break;
-
- case Q_DST:
- offset = dst_off;
- break;
-
- case Q_AND:
- b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off);
- b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
- gen_and(b0, b1);
- return b1;
-
- case Q_OR:
- case Q_DEFAULT:
- b0 = gen_hostop(addr, mask, Q_SRC, proto, src_off, dst_off);
- b1 = gen_hostop(addr, mask, Q_DST, proto, src_off, dst_off);
- gen_or(b0, b1);
- return b1;
-
- default:
- abort();
- }
- b0 = gen_linktype(proto);
- b1 = gen_mcmp(OR_NET, offset, BPF_W, (bpf_int32)addr, mask);
- gen_and(b0, b1);
- return b1;
-}
-
-#ifdef INET6
-static struct block *
-gen_hostop6(addr, mask, dir, proto, src_off, dst_off)
- struct in6_addr *addr;
- struct in6_addr *mask;
- int dir, proto;
- u_int src_off, dst_off;
-{
- struct block *b0, *b1;
- u_int offset;
- u_int32_t *a, *m;
-
- switch (dir) {
-
- case Q_SRC:
- offset = src_off;
- break;
-
- case Q_DST:
- offset = dst_off;
- break;
-
- case Q_AND:
- b0 = gen_hostop6(addr, mask, Q_SRC, proto, src_off, dst_off);
- b1 = gen_hostop6(addr, mask, Q_DST, proto, src_off, dst_off);
- gen_and(b0, b1);
- return b1;
-
- case Q_OR:
- case Q_DEFAULT:
- b0 = gen_hostop6(addr, mask, Q_SRC, proto, src_off, dst_off);
- b1 = gen_hostop6(addr, mask, Q_DST, proto, src_off, dst_off);
- gen_or(b0, b1);
- return b1;
-
- default:
- abort();
- }
- /* this order is important */
- a = (u_int32_t *)addr;
- m = (u_int32_t *)mask;
- b1 = gen_mcmp(OR_NET, offset + 12, BPF_W, ntohl(a[3]), ntohl(m[3]));
- b0 = gen_mcmp(OR_NET, offset + 8, BPF_W, ntohl(a[2]), ntohl(m[2]));
- gen_and(b0, b1);
- b0 = gen_mcmp(OR_NET, offset + 4, BPF_W, ntohl(a[1]), ntohl(m[1]));
- gen_and(b0, b1);
- b0 = gen_mcmp(OR_NET, offset + 0, BPF_W, ntohl(a[0]), ntohl(m[0]));
- gen_and(b0, b1);
- b0 = gen_linktype(proto);
- gen_and(b0, b1);
- return b1;
-}
-#endif /*INET6*/
-
-static struct block *
-gen_ehostop(eaddr, dir)
- register const u_char *eaddr;
- register int dir;
-{
- register struct block *b0, *b1;
-
- switch (dir) {
- case Q_SRC:
- return gen_bcmp(OR_LINK, off_mac + 6, 6, eaddr);
-
- case Q_DST:
- return gen_bcmp(OR_LINK, off_mac + 0, 6, eaddr);
-
- case Q_AND:
- b0 = gen_ehostop(eaddr, Q_SRC);
- b1 = gen_ehostop(eaddr, Q_DST);
- gen_and(b0, b1);
- return b1;
-
- case Q_DEFAULT:
- case Q_OR:
- b0 = gen_ehostop(eaddr, Q_SRC);
- b1 = gen_ehostop(eaddr, Q_DST);
- gen_or(b0, b1);
- return b1;
- }
- abort();
- /* NOTREACHED */
-}
-
-/*
- * Like gen_ehostop, but for DLT_FDDI
- */
-static struct block *
-gen_fhostop(eaddr, dir)
- register const u_char *eaddr;
- register int dir;
-{
- struct block *b0, *b1;
-
- switch (dir) {
- case Q_SRC:
-#ifdef PCAP_FDDIPAD
- return gen_bcmp(OR_LINK, 6 + 1 + pcap_fddipad, 6, eaddr);
-#else
- return gen_bcmp(OR_LINK, 6 + 1, 6, eaddr);
-#endif
-
- case Q_DST:
-#ifdef PCAP_FDDIPAD
- return gen_bcmp(OR_LINK, 0 + 1 + pcap_fddipad, 6, eaddr);
-#else
- return gen_bcmp(OR_LINK, 0 + 1, 6, eaddr);
-#endif
-
- case Q_AND:
- b0 = gen_fhostop(eaddr, Q_SRC);
- b1 = gen_fhostop(eaddr, Q_DST);
- gen_and(b0, b1);
- return b1;
-
- case Q_DEFAULT:
- case Q_OR:
- b0 = gen_fhostop(eaddr, Q_SRC);
- b1 = gen_fhostop(eaddr, Q_DST);
- gen_or(b0, b1);
- return b1;
- }
- abort();
- /* NOTREACHED */
-}
-
-/*
- * Like gen_ehostop, but for DLT_IEEE802 (Token Ring)
- */
-static struct block *
-gen_thostop(eaddr, dir)
- register const u_char *eaddr;
- register int dir;
-{
- register struct block *b0, *b1;
-
- switch (dir) {
- case Q_SRC:
- return gen_bcmp(OR_LINK, 8, 6, eaddr);
-
- case Q_DST:
- return gen_bcmp(OR_LINK, 2, 6, eaddr);
-
- case Q_AND:
- b0 = gen_thostop(eaddr, Q_SRC);
- b1 = gen_thostop(eaddr, Q_DST);
- gen_and(b0, b1);
- return b1;
-
- case Q_DEFAULT:
- case Q_OR:
- b0 = gen_thostop(eaddr, Q_SRC);
- b1 = gen_thostop(eaddr, Q_DST);
- gen_or(b0, b1);
- return b1;
- }
- abort();
- /* NOTREACHED */
-}
-
-/*
- * Like gen_ehostop, but for DLT_IEEE802_11 (802.11 wireless LAN)
- */
-static struct block *
-gen_wlanhostop(eaddr, dir)
- register const u_char *eaddr;
- register int dir;
-{
- register struct block *b0, *b1, *b2;
- register struct slist *s;
-
- switch (dir) {
- case Q_SRC:
- /*
- * Oh, yuk.
- *
- * For control frames, there is no SA.
- *
- * For management frames, SA is at an
- * offset of 10 from the beginning of
- * the packet.
- *
- * For data frames, SA is at an offset
- * of 10 from the beginning of the packet
- * if From DS is clear, at an offset of
- * 16 from the beginning of the packet
- * if From DS is set and To DS is clear,
- * and an offset of 24 from the beginning
- * of the packet if From DS is set and To DS
- * is set.
- */
-
- /*
- * Generate the tests to be done for data frames
- * with From DS set.
- *
- * First, check for To DS set, i.e. check "link[1] & 0x01".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x01; /* To DS */
- b1->stmts = s;
-
- /*
- * If To DS is set, the SA is at 24.
- */
- b0 = gen_bcmp(OR_LINK, 24, 6, eaddr);
- gen_and(b1, b0);
-
- /*
- * Now, check for To DS not set, i.e. check
- * "!(link[1] & 0x01)".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x01; /* To DS */
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * If To DS is not set, the SA is at 16.
- */
- b1 = gen_bcmp(OR_LINK, 16, 6, eaddr);
- gen_and(b2, b1);
-
- /*
- * Now OR together the last two checks. That gives
- * the complete set of checks for data frames with
- * From DS set.
- */
- gen_or(b1, b0);
-
- /*
- * Now check for From DS being set, and AND that with
- * the ORed-together checks.
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x02; /* From DS */
- b1->stmts = s;
- gen_and(b1, b0);
-
- /*
- * Now check for data frames with From DS not set.
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x02; /* From DS */
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * If From DS isn't set, the SA is at 10.
- */
- b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
- gen_and(b2, b1);
-
- /*
- * Now OR together the checks for data frames with
- * From DS not set and for data frames with From DS
- * set; that gives the checks done for data frames.
- */
- gen_or(b1, b0);
-
- /*
- * Now check for a data frame.
- * I.e, check "link[0] & 0x08".
- */
- gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x08;
- b1->stmts = s;
-
- /*
- * AND that with the checks done for data frames.
- */
- gen_and(b1, b0);
-
- /*
- * If the high-order bit of the type value is 0, this
- * is a management frame.
- * I.e, check "!(link[0] & 0x08)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x08;
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * For management frames, the SA is at 10.
- */
- b1 = gen_bcmp(OR_LINK, 10, 6, eaddr);
- gen_and(b2, b1);
-
- /*
- * OR that with the checks done for data frames.
- * That gives the checks done for management and
- * data frames.
- */
- gen_or(b1, b0);
-
- /*
- * If the low-order bit of the type value is 1,
- * this is either a control frame or a frame
- * with a reserved type, and thus not a
- * frame with an SA.
- *
- * I.e., check "!(link[0] & 0x04)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x04;
- b1->stmts = s;
- gen_not(b1);
-
- /*
- * AND that with the checks for data and management
- * frames.
- */
- gen_and(b1, b0);
- return b0;
-
- case Q_DST:
- /*
- * Oh, yuk.
- *
- * For control frames, there is no DA.
- *
- * For management frames, DA is at an
- * offset of 4 from the beginning of
- * the packet.
- *
- * For data frames, DA is at an offset
- * of 4 from the beginning of the packet
- * if To DS is clear and at an offset of
- * 16 from the beginning of the packet
- * if To DS is set.
- */
-
- /*
- * Generate the tests to be done for data frames.
- *
- * First, check for To DS set, i.e. "link[1] & 0x01".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x01; /* To DS */
- b1->stmts = s;
-
- /*
- * If To DS is set, the DA is at 16.
- */
- b0 = gen_bcmp(OR_LINK, 16, 6, eaddr);
- gen_and(b1, b0);
-
- /*
- * Now, check for To DS not set, i.e. check
- * "!(link[1] & 0x01)".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x01; /* To DS */
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * If To DS is not set, the DA is at 4.
- */
- b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
- gen_and(b2, b1);
-
- /*
- * Now OR together the last two checks. That gives
- * the complete set of checks for data frames.
- */
- gen_or(b1, b0);
-
- /*
- * Now check for a data frame.
- * I.e, check "link[0] & 0x08".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x08;
- b1->stmts = s;
-
- /*
- * AND that with the checks done for data frames.
- */
- gen_and(b1, b0);
-
- /*
- * If the high-order bit of the type value is 0, this
- * is a management frame.
- * I.e, check "!(link[0] & 0x08)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x08;
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * For management frames, the DA is at 4.
- */
- b1 = gen_bcmp(OR_LINK, 4, 6, eaddr);
- gen_and(b2, b1);
-
- /*
- * OR that with the checks done for data frames.
- * That gives the checks done for management and
- * data frames.
- */
- gen_or(b1, b0);
-
- /*
- * If the low-order bit of the type value is 1,
- * this is either a control frame or a frame
- * with a reserved type, and thus not a
- * frame with an SA.
- *
- * I.e., check "!(link[0] & 0x04)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x04;
- b1->stmts = s;
- gen_not(b1);
-
- /*
- * AND that with the checks for data and management
- * frames.
- */
- gen_and(b1, b0);
- return b0;
-
- case Q_AND:
- b0 = gen_wlanhostop(eaddr, Q_SRC);
- b1 = gen_wlanhostop(eaddr, Q_DST);
- gen_and(b0, b1);
- return b1;
-
- case Q_DEFAULT:
- case Q_OR:
- b0 = gen_wlanhostop(eaddr, Q_SRC);
- b1 = gen_wlanhostop(eaddr, Q_DST);
- gen_or(b0, b1);
- return b1;
- }
- abort();
- /* NOTREACHED */
-}
-
-/*
- * Like gen_ehostop, but for RFC 2625 IP-over-Fibre-Channel.
- * (We assume that the addresses are IEEE 48-bit MAC addresses,
- * as the RFC states.)
- */
-static struct block *
-gen_ipfchostop(eaddr, dir)
- register const u_char *eaddr;
- register int dir;
-{
- register struct block *b0, *b1;
-
- switch (dir) {
- case Q_SRC:
- return gen_bcmp(OR_LINK, 10, 6, eaddr);
-
- case Q_DST:
- return gen_bcmp(OR_LINK, 2, 6, eaddr);
-
- case Q_AND:
- b0 = gen_ipfchostop(eaddr, Q_SRC);
- b1 = gen_ipfchostop(eaddr, Q_DST);
- gen_and(b0, b1);
- return b1;
-
- case Q_DEFAULT:
- case Q_OR:
- b0 = gen_ipfchostop(eaddr, Q_SRC);
- b1 = gen_ipfchostop(eaddr, Q_DST);
- gen_or(b0, b1);
- return b1;
- }
- abort();
- /* NOTREACHED */
-}
-
-/*
- * This is quite tricky because there may be pad bytes in front of the
- * DECNET header, and then there are two possible data packet formats that
- * carry both src and dst addresses, plus 5 packet types in a format that
- * carries only the src node, plus 2 types that use a different format and
- * also carry just the src node.
- *
- * Yuck.
- *
- * Instead of doing those all right, we just look for data packets with
- * 0 or 1 bytes of padding. If you want to look at other packets, that
- * will require a lot more hacking.
- *
- * To add support for filtering on DECNET "areas" (network numbers)
- * one would want to add a "mask" argument to this routine. That would
- * make the filter even more inefficient, although one could be clever
- * and not generate masking instructions if the mask is 0xFFFF.
- */
-static struct block *
-gen_dnhostop(addr, dir)
- bpf_u_int32 addr;
- int dir;
-{
- struct block *b0, *b1, *b2, *tmp;
- u_int offset_lh; /* offset if long header is received */
- u_int offset_sh; /* offset if short header is received */
-
- switch (dir) {
-
- case Q_DST:
- offset_sh = 1; /* follows flags */
- offset_lh = 7; /* flgs,darea,dsubarea,HIORD */
- break;
-
- case Q_SRC:
- offset_sh = 3; /* follows flags, dstnode */
- offset_lh = 15; /* flgs,darea,dsubarea,did,sarea,ssub,HIORD */
- break;
-
- case Q_AND:
- /* Inefficient because we do our Calvinball dance twice */
- b0 = gen_dnhostop(addr, Q_SRC);
- b1 = gen_dnhostop(addr, Q_DST);
- gen_and(b0, b1);
- return b1;
-
- case Q_OR:
- case Q_DEFAULT:
- /* Inefficient because we do our Calvinball dance twice */
- b0 = gen_dnhostop(addr, Q_SRC);
- b1 = gen_dnhostop(addr, Q_DST);
- gen_or(b0, b1);
- return b1;
-
- case Q_ISO:
- bpf_error("ISO host filtering not implemented");
-
- default:
- abort();
- }
- b0 = gen_linktype(ETHERTYPE_DN);
- /* Check for pad = 1, long header case */
- tmp = gen_mcmp(OR_NET, 2, BPF_H,
- (bpf_int32)ntohs(0x0681), (bpf_int32)ntohs(0x07FF));
- b1 = gen_cmp(OR_NET, 2 + 1 + offset_lh,
- BPF_H, (bpf_int32)ntohs((u_short)addr));
- gen_and(tmp, b1);
- /* Check for pad = 0, long header case */
- tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x06, (bpf_int32)0x7);
- b2 = gen_cmp(OR_NET, 2 + offset_lh, BPF_H, (bpf_int32)ntohs((u_short)addr));
- gen_and(tmp, b2);
- gen_or(b2, b1);
- /* Check for pad = 1, short header case */
- tmp = gen_mcmp(OR_NET, 2, BPF_H,
- (bpf_int32)ntohs(0x0281), (bpf_int32)ntohs(0x07FF));
- b2 = gen_cmp(OR_NET, 2 + 1 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
- gen_and(tmp, b2);
- gen_or(b2, b1);
- /* Check for pad = 0, short header case */
- tmp = gen_mcmp(OR_NET, 2, BPF_B, (bpf_int32)0x02, (bpf_int32)0x7);
- b2 = gen_cmp(OR_NET, 2 + offset_sh, BPF_H, (bpf_int32)ntohs((u_short)addr));
- gen_and(tmp, b2);
- gen_or(b2, b1);
-
- /* Combine with test for linktype */
- gen_and(b0, b1);
- return b1;
-}
-
-/*
- * Generate a check for IPv4 or IPv6 for MPLS-encapsulated packets;
- * test the bottom-of-stack bit, and then check the version number
- * field in the IP header.
- */
-static struct block *
-gen_mpls_linktype(proto)
- int proto;
-{
- struct block *b0, *b1;
-
- switch (proto) {
-
- case Q_IP:
- /* match the bottom-of-stack bit */
- b0 = gen_mcmp(OR_NET, -2, BPF_B, 0x01, 0x01);
- /* match the IPv4 version number */
- b1 = gen_mcmp(OR_NET, 0, BPF_B, 0x40, 0xf0);
- gen_and(b0, b1);
- return b1;
-
- case Q_IPV6:
- /* match the bottom-of-stack bit */
- b0 = gen_mcmp(OR_NET, -2, BPF_B, 0x01, 0x01);
- /* match the IPv4 version number */
- b1 = gen_mcmp(OR_NET, 0, BPF_B, 0x60, 0xf0);
- gen_and(b0, b1);
- return b1;
-
- default:
- abort();
- }
-}
-
-static struct block *
-gen_host(addr, mask, proto, dir, type)
- bpf_u_int32 addr;
- bpf_u_int32 mask;
- int proto;
- int dir;
- int type;
-{
- struct block *b0, *b1;
- const char *typestr;
-
- if (type == Q_NET)
- typestr = "net";
- else
- typestr = "host";
-
- switch (proto) {
-
- case Q_DEFAULT:
- b0 = gen_host(addr, mask, Q_IP, dir, type);
- /*
- * Only check for non-IPv4 addresses if we're not
- * checking MPLS-encapsulated packets.
- */
- if (label_stack_depth == 0) {
- b1 = gen_host(addr, mask, Q_ARP, dir, type);
- gen_or(b0, b1);
- b0 = gen_host(addr, mask, Q_RARP, dir, type);
- gen_or(b1, b0);
- }
- return b0;
-
- case Q_IP:
- return gen_hostop(addr, mask, dir, ETHERTYPE_IP, 12, 16);
-
- case Q_RARP:
- return gen_hostop(addr, mask, dir, ETHERTYPE_REVARP, 14, 24);
-
- case Q_ARP:
- return gen_hostop(addr, mask, dir, ETHERTYPE_ARP, 14, 24);
-
- case Q_TCP:
- bpf_error("'tcp' modifier applied to %s", typestr);
-
- case Q_SCTP:
- bpf_error("'sctp' modifier applied to %s", typestr);
-
- case Q_UDP:
- bpf_error("'udp' modifier applied to %s", typestr);
-
- case Q_ICMP:
- bpf_error("'icmp' modifier applied to %s", typestr);
-
- case Q_IGMP:
- bpf_error("'igmp' modifier applied to %s", typestr);
-
- case Q_IGRP:
- bpf_error("'igrp' modifier applied to %s", typestr);
-
- case Q_PIM:
- bpf_error("'pim' modifier applied to %s", typestr);
-
- case Q_VRRP:
- bpf_error("'vrrp' modifier applied to %s", typestr);
-
- case Q_ATALK:
- bpf_error("ATALK host filtering not implemented");
-
- case Q_AARP:
- bpf_error("AARP host filtering not implemented");
-
- case Q_DECNET:
- return gen_dnhostop(addr, dir);
-
- case Q_SCA:
- bpf_error("SCA host filtering not implemented");
-
- case Q_LAT:
- bpf_error("LAT host filtering not implemented");
-
- case Q_MOPDL:
- bpf_error("MOPDL host filtering not implemented");
-
- case Q_MOPRC:
- bpf_error("MOPRC host filtering not implemented");
-
-#ifdef INET6
- case Q_IPV6:
- bpf_error("'ip6' modifier applied to ip host");
-
- case Q_ICMPV6:
- bpf_error("'icmp6' modifier applied to %s", typestr);
-#endif /* INET6 */
-
- case Q_AH:
- bpf_error("'ah' modifier applied to %s", typestr);
-
- case Q_ESP:
- bpf_error("'esp' modifier applied to %s", typestr);
-
- case Q_ISO:
- bpf_error("ISO host filtering not implemented");
-
- case Q_ESIS:
- bpf_error("'esis' modifier applied to %s", typestr);
-
- case Q_ISIS:
- bpf_error("'isis' modifier applied to %s", typestr);
-
- case Q_CLNP:
- bpf_error("'clnp' modifier applied to %s", typestr);
-
- case Q_STP:
- bpf_error("'stp' modifier applied to %s", typestr);
-
- case Q_IPX:
- bpf_error("IPX host filtering not implemented");
-
- case Q_NETBEUI:
- bpf_error("'netbeui' modifier applied to %s", typestr);
-
- case Q_RADIO:
- bpf_error("'radio' modifier applied to %s", typestr);
-
- default:
- abort();
- }
- /* NOTREACHED */
-}
-
-#ifdef INET6
-static struct block *
-gen_host6(addr, mask, proto, dir, type)
- struct in6_addr *addr;
- struct in6_addr *mask;
- int proto;
- int dir;
- int type;
-{
- const char *typestr;
-
- if (type == Q_NET)
- typestr = "net";
- else
- typestr = "host";
-
- switch (proto) {
-
- case Q_DEFAULT:
- return gen_host6(addr, mask, Q_IPV6, dir, type);
-
- case Q_IP:
- bpf_error("'ip' modifier applied to ip6 %s", typestr);
-
- case Q_RARP:
- bpf_error("'rarp' modifier applied to ip6 %s", typestr);
-
- case Q_ARP:
- bpf_error("'arp' modifier applied to ip6 %s", typestr);
-
- case Q_SCTP:
- bpf_error("'sctp' modifier applied to %s", typestr);
-
- case Q_TCP:
- bpf_error("'tcp' modifier applied to %s", typestr);
-
- case Q_UDP:
- bpf_error("'udp' modifier applied to %s", typestr);
-
- case Q_ICMP:
- bpf_error("'icmp' modifier applied to %s", typestr);
-
- case Q_IGMP:
- bpf_error("'igmp' modifier applied to %s", typestr);
-
- case Q_IGRP:
- bpf_error("'igrp' modifier applied to %s", typestr);
-
- case Q_PIM:
- bpf_error("'pim' modifier applied to %s", typestr);
-
- case Q_VRRP:
- bpf_error("'vrrp' modifier applied to %s", typestr);
-
- case Q_ATALK:
- bpf_error("ATALK host filtering not implemented");
-
- case Q_AARP:
- bpf_error("AARP host filtering not implemented");
-
- case Q_DECNET:
- bpf_error("'decnet' modifier applied to ip6 %s", typestr);
-
- case Q_SCA:
- bpf_error("SCA host filtering not implemented");
-
- case Q_LAT:
- bpf_error("LAT host filtering not implemented");
-
- case Q_MOPDL:
- bpf_error("MOPDL host filtering not implemented");
-
- case Q_MOPRC:
- bpf_error("MOPRC host filtering not implemented");
-
- case Q_IPV6:
- return gen_hostop6(addr, mask, dir, ETHERTYPE_IPV6, 8, 24);
-
- case Q_ICMPV6:
- bpf_error("'icmp6' modifier applied to %s", typestr);
-
- case Q_AH:
- bpf_error("'ah' modifier applied to %s", typestr);
-
- case Q_ESP:
- bpf_error("'esp' modifier applied to %s", typestr);
-
- case Q_ISO:
- bpf_error("ISO host filtering not implemented");
-
- case Q_ESIS:
- bpf_error("'esis' modifier applied to %s", typestr);
-
- case Q_ISIS:
- bpf_error("'isis' modifier applied to %s", typestr);
-
- case Q_CLNP:
- bpf_error("'clnp' modifier applied to %s", typestr);
-
- case Q_STP:
- bpf_error("'stp' modifier applied to %s", typestr);
-
- case Q_IPX:
- bpf_error("IPX host filtering not implemented");
-
- case Q_NETBEUI:
- bpf_error("'netbeui' modifier applied to %s", typestr);
-
- case Q_RADIO:
- bpf_error("'radio' modifier applied to %s", typestr);
-
- default:
- abort();
- }
- /* NOTREACHED */
-}
-#endif /*INET6*/
-
-#ifndef INET6
-static struct block *
-gen_gateway(eaddr, alist, proto, dir)
- const u_char *eaddr;
- bpf_u_int32 **alist;
- int proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- if (dir != 0)
- bpf_error("direction applied to 'gateway'");
-
- switch (proto) {
- case Q_DEFAULT:
- case Q_IP:
- case Q_ARP:
- case Q_RARP:
- switch (linktype) {
- case DLT_EN10MB:
- b0 = gen_ehostop(eaddr, Q_OR);
- break;
- case DLT_FDDI:
- b0 = gen_fhostop(eaddr, Q_OR);
- break;
- case DLT_IEEE802:
- b0 = gen_thostop(eaddr, Q_OR);
- break;
- case DLT_IEEE802_11:
- case DLT_IEEE802_11_RADIO_AVS:
- case DLT_PPI:
- case DLT_IEEE802_11_RADIO:
- case DLT_PRISM_HEADER:
- b0 = gen_wlanhostop(eaddr, Q_OR);
- break;
- case DLT_SUNATM:
- if (is_lane) {
- /*
- * Check that the packet doesn't begin with an
- * LE Control marker. (We've already generated
- * a test for LANE.)
- */
- b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
- 0xFF00);
- gen_not(b1);
-
- /*
- * Now check the MAC address.
- */
- b0 = gen_ehostop(eaddr, Q_OR);
- gen_and(b1, b0);
- }
- break;
- case DLT_IP_OVER_FC:
- b0 = gen_ipfchostop(eaddr, Q_OR);
- break;
- default:
- bpf_error(
- "'gateway' supported only on ethernet/FDDI/token ring/802.11/Fibre Channel");
- }
- b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR, Q_HOST);
- while (*alist) {
- tmp = gen_host(**alist++, 0xffffffff, proto, Q_OR,
- Q_HOST);
- gen_or(b1, tmp);
- b1 = tmp;
- }
- gen_not(b1);
- gen_and(b0, b1);
- return b1;
- }
- bpf_error("illegal modifier of 'gateway'");
- /* NOTREACHED */
-}
-#endif
-
-struct block *
-gen_proto_abbrev(proto)
- int proto;
-{
- struct block *b0;
- struct block *b1;
-
- switch (proto) {
-
- case Q_SCTP:
- b1 = gen_proto(IPPROTO_SCTP, Q_IP, Q_DEFAULT);
-#ifdef INET6
- b0 = gen_proto(IPPROTO_SCTP, Q_IPV6, Q_DEFAULT);
- gen_or(b0, b1);
-#endif
- break;
-
- case Q_TCP:
- b1 = gen_proto(IPPROTO_TCP, Q_IP, Q_DEFAULT);
-#ifdef INET6
- b0 = gen_proto(IPPROTO_TCP, Q_IPV6, Q_DEFAULT);
- gen_or(b0, b1);
-#endif
- break;
-
- case Q_UDP:
- b1 = gen_proto(IPPROTO_UDP, Q_IP, Q_DEFAULT);
-#ifdef INET6
- b0 = gen_proto(IPPROTO_UDP, Q_IPV6, Q_DEFAULT);
- gen_or(b0, b1);
-#endif
- break;
-
- case Q_ICMP:
- b1 = gen_proto(IPPROTO_ICMP, Q_IP, Q_DEFAULT);
- break;
-
-#ifndef IPPROTO_IGMP
-#define IPPROTO_IGMP 2
-#endif
-
- case Q_IGMP:
- b1 = gen_proto(IPPROTO_IGMP, Q_IP, Q_DEFAULT);
- break;
-
-#ifndef IPPROTO_IGRP
-#define IPPROTO_IGRP 9
-#endif
- case Q_IGRP:
- b1 = gen_proto(IPPROTO_IGRP, Q_IP, Q_DEFAULT);
- break;
-
-#ifndef IPPROTO_PIM
-#define IPPROTO_PIM 103
-#endif
-
- case Q_PIM:
- b1 = gen_proto(IPPROTO_PIM, Q_IP, Q_DEFAULT);
-#ifdef INET6
- b0 = gen_proto(IPPROTO_PIM, Q_IPV6, Q_DEFAULT);
- gen_or(b0, b1);
-#endif
- break;
-
-#ifndef IPPROTO_VRRP
-#define IPPROTO_VRRP 112
-#endif
-
- case Q_VRRP:
- b1 = gen_proto(IPPROTO_VRRP, Q_IP, Q_DEFAULT);
- break;
-
- case Q_IP:
- b1 = gen_linktype(ETHERTYPE_IP);
- break;
-
- case Q_ARP:
- b1 = gen_linktype(ETHERTYPE_ARP);
- break;
-
- case Q_RARP:
- b1 = gen_linktype(ETHERTYPE_REVARP);
- break;
-
- case Q_LINK:
- bpf_error("link layer applied in wrong context");
-
- case Q_ATALK:
- b1 = gen_linktype(ETHERTYPE_ATALK);
- break;
-
- case Q_AARP:
- b1 = gen_linktype(ETHERTYPE_AARP);
- break;
-
- case Q_DECNET:
- b1 = gen_linktype(ETHERTYPE_DN);
- break;
-
- case Q_SCA:
- b1 = gen_linktype(ETHERTYPE_SCA);
- break;
-
- case Q_LAT:
- b1 = gen_linktype(ETHERTYPE_LAT);
- break;
-
- case Q_MOPDL:
- b1 = gen_linktype(ETHERTYPE_MOPDL);
- break;
-
- case Q_MOPRC:
- b1 = gen_linktype(ETHERTYPE_MOPRC);
- break;
-
-#ifdef INET6
- case Q_IPV6:
- b1 = gen_linktype(ETHERTYPE_IPV6);
- break;
-
-#ifndef IPPROTO_ICMPV6
-#define IPPROTO_ICMPV6 58
-#endif
- case Q_ICMPV6:
- b1 = gen_proto(IPPROTO_ICMPV6, Q_IPV6, Q_DEFAULT);
- break;
-#endif /* INET6 */
-
-#ifndef IPPROTO_AH
-#define IPPROTO_AH 51
-#endif
- case Q_AH:
- b1 = gen_proto(IPPROTO_AH, Q_IP, Q_DEFAULT);
-#ifdef INET6
- b0 = gen_proto(IPPROTO_AH, Q_IPV6, Q_DEFAULT);
- gen_or(b0, b1);
-#endif
- break;
-
-#ifndef IPPROTO_ESP
-#define IPPROTO_ESP 50
-#endif
- case Q_ESP:
- b1 = gen_proto(IPPROTO_ESP, Q_IP, Q_DEFAULT);
-#ifdef INET6
- b0 = gen_proto(IPPROTO_ESP, Q_IPV6, Q_DEFAULT);
- gen_or(b0, b1);
-#endif
- break;
-
- case Q_ISO:
- b1 = gen_linktype(LLCSAP_ISONS);
- break;
-
- case Q_ESIS:
- b1 = gen_proto(ISO9542_ESIS, Q_ISO, Q_DEFAULT);
- break;
-
- case Q_ISIS:
- b1 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
- break;
-
- case Q_ISIS_L1: /* all IS-IS Level1 PDU-Types */
- b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT);
- b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- break;
-
- case Q_ISIS_L2: /* all IS-IS Level2 PDU-Types */
- b0 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT);
- b1 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT); /* FIXME extract the circuit-type bits */
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- break;
-
- case Q_ISIS_IIH: /* all IS-IS Hello PDU-Types */
- b0 = gen_proto(ISIS_L1_LAN_IIH, Q_ISIS, Q_DEFAULT);
- b1 = gen_proto(ISIS_L2_LAN_IIH, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_PTP_IIH, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- break;
-
- case Q_ISIS_LSP:
- b0 = gen_proto(ISIS_L1_LSP, Q_ISIS, Q_DEFAULT);
- b1 = gen_proto(ISIS_L2_LSP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- break;
-
- case Q_ISIS_SNP:
- b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
- b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- b0 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- break;
-
- case Q_ISIS_CSNP:
- b0 = gen_proto(ISIS_L1_CSNP, Q_ISIS, Q_DEFAULT);
- b1 = gen_proto(ISIS_L2_CSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- break;
-
- case Q_ISIS_PSNP:
- b0 = gen_proto(ISIS_L1_PSNP, Q_ISIS, Q_DEFAULT);
- b1 = gen_proto(ISIS_L2_PSNP, Q_ISIS, Q_DEFAULT);
- gen_or(b0, b1);
- break;
-
- case Q_CLNP:
- b1 = gen_proto(ISO8473_CLNP, Q_ISO, Q_DEFAULT);
- break;
-
- case Q_STP:
- b1 = gen_linktype(LLCSAP_8021D);
- break;
-
- case Q_IPX:
- b1 = gen_linktype(LLCSAP_IPX);
- break;
-
- case Q_NETBEUI:
- b1 = gen_linktype(LLCSAP_NETBEUI);
- break;
-
- case Q_RADIO:
- bpf_error("'radio' is not a valid protocol type");
-
- default:
- abort();
- }
- return b1;
-}
-
-static struct block *
-gen_ipfrag()
-{
- struct slist *s;
- struct block *b;
-
- /* not ip frag */
- s = gen_load_a(OR_NET, 6, BPF_H);
- b = new_block(JMP(BPF_JSET));
- b->s.k = 0x1fff;
- b->stmts = s;
- gen_not(b);
-
- return b;
-}
-
-/*
- * Generate a comparison to a port value in the transport-layer header
- * at the specified offset from the beginning of that header.
- *
- * XXX - this handles a variable-length prefix preceding the link-layer
- * header, such as the radiotap or AVS radio prefix, but doesn't handle
- * variable-length link-layer headers (such as Token Ring or 802.11
- * headers).
- */
-static struct block *
-gen_portatom(off, v)
- int off;
- bpf_int32 v;
-{
- return gen_cmp(OR_TRAN_IPV4, off, BPF_H, v);
-}
-
-#ifdef INET6
-static struct block *
-gen_portatom6(off, v)
- int off;
- bpf_int32 v;
-{
- return gen_cmp(OR_TRAN_IPV6, off, BPF_H, v);
-}
-#endif/*INET6*/
-
-struct block *
-gen_portop(port, proto, dir)
- int port, proto, dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* ip proto 'proto' */
- tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto);
- b0 = gen_ipfrag();
- gen_and(tmp, b0);
-
- switch (dir) {
- case Q_SRC:
- b1 = gen_portatom(0, (bpf_int32)port);
- break;
-
- case Q_DST:
- b1 = gen_portatom(2, (bpf_int32)port);
- break;
-
- case Q_OR:
- case Q_DEFAULT:
- tmp = gen_portatom(0, (bpf_int32)port);
- b1 = gen_portatom(2, (bpf_int32)port);
- gen_or(tmp, b1);
- break;
-
- case Q_AND:
- tmp = gen_portatom(0, (bpf_int32)port);
- b1 = gen_portatom(2, (bpf_int32)port);
- gen_and(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
-
- return b1;
-}
-
-static struct block *
-gen_port(port, ip_proto, dir)
- int port;
- int ip_proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /*
- * ether proto ip
- *
- * For FDDI, RFC 1188 says that SNAP encapsulation is used,
- * not LLC encapsulation with LLCSAP_IP.
- *
- * For IEEE 802 networks - which includes 802.5 token ring
- * (which is what DLT_IEEE802 means) and 802.11 - RFC 1042
- * says that SNAP encapsulation is used, not LLC encapsulation
- * with LLCSAP_IP.
- *
- * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and
- * RFC 2225 say that SNAP encapsulation is used, not LLC
- * encapsulation with LLCSAP_IP.
- *
- * So we always check for ETHERTYPE_IP.
- */
- b0 = gen_linktype(ETHERTYPE_IP);
-
- switch (ip_proto) {
- case IPPROTO_UDP:
- case IPPROTO_TCP:
- case IPPROTO_SCTP:
- b1 = gen_portop(port, ip_proto, dir);
- break;
-
- case PROTO_UNDEF:
- tmp = gen_portop(port, IPPROTO_TCP, dir);
- b1 = gen_portop(port, IPPROTO_UDP, dir);
- gen_or(tmp, b1);
- tmp = gen_portop(port, IPPROTO_SCTP, dir);
- gen_or(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
- return b1;
-}
-
-#ifdef INET6
-struct block *
-gen_portop6(port, proto, dir)
- int port, proto, dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* ip6 proto 'proto' */
- b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto);
-
- switch (dir) {
- case Q_SRC:
- b1 = gen_portatom6(0, (bpf_int32)port);
- break;
-
- case Q_DST:
- b1 = gen_portatom6(2, (bpf_int32)port);
- break;
-
- case Q_OR:
- case Q_DEFAULT:
- tmp = gen_portatom6(0, (bpf_int32)port);
- b1 = gen_portatom6(2, (bpf_int32)port);
- gen_or(tmp, b1);
- break;
-
- case Q_AND:
- tmp = gen_portatom6(0, (bpf_int32)port);
- b1 = gen_portatom6(2, (bpf_int32)port);
- gen_and(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
-
- return b1;
-}
-
-static struct block *
-gen_port6(port, ip_proto, dir)
- int port;
- int ip_proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* link proto ip6 */
- b0 = gen_linktype(ETHERTYPE_IPV6);
-
- switch (ip_proto) {
- case IPPROTO_UDP:
- case IPPROTO_TCP:
- case IPPROTO_SCTP:
- b1 = gen_portop6(port, ip_proto, dir);
- break;
-
- case PROTO_UNDEF:
- tmp = gen_portop6(port, IPPROTO_TCP, dir);
- b1 = gen_portop6(port, IPPROTO_UDP, dir);
- gen_or(tmp, b1);
- tmp = gen_portop6(port, IPPROTO_SCTP, dir);
- gen_or(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
- return b1;
-}
-#endif /* INET6 */
-
-/* gen_portrange code */
-static struct block *
-gen_portrangeatom(off, v1, v2)
- int off;
- bpf_int32 v1, v2;
-{
- struct block *b1, *b2;
-
- if (v1 > v2) {
- /*
- * Reverse the order of the ports, so v1 is the lower one.
- */
- bpf_int32 vtemp;
-
- vtemp = v1;
- v1 = v2;
- v2 = vtemp;
- }
-
- b1 = gen_cmp_ge(OR_TRAN_IPV4, off, BPF_H, v1);
- b2 = gen_cmp_le(OR_TRAN_IPV4, off, BPF_H, v2);
-
- gen_and(b1, b2);
-
- return b2;
-}
-
-struct block *
-gen_portrangeop(port1, port2, proto, dir)
- int port1, port2;
- int proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* ip proto 'proto' */
- tmp = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)proto);
- b0 = gen_ipfrag();
- gen_and(tmp, b0);
-
- switch (dir) {
- case Q_SRC:
- b1 = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
- break;
-
- case Q_DST:
- b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
- break;
-
- case Q_OR:
- case Q_DEFAULT:
- tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
- b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
- gen_or(tmp, b1);
- break;
-
- case Q_AND:
- tmp = gen_portrangeatom(0, (bpf_int32)port1, (bpf_int32)port2);
- b1 = gen_portrangeatom(2, (bpf_int32)port1, (bpf_int32)port2);
- gen_and(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
-
- return b1;
-}
-
-static struct block *
-gen_portrange(port1, port2, ip_proto, dir)
- int port1, port2;
- int ip_proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* link proto ip */
- b0 = gen_linktype(ETHERTYPE_IP);
-
- switch (ip_proto) {
- case IPPROTO_UDP:
- case IPPROTO_TCP:
- case IPPROTO_SCTP:
- b1 = gen_portrangeop(port1, port2, ip_proto, dir);
- break;
-
- case PROTO_UNDEF:
- tmp = gen_portrangeop(port1, port2, IPPROTO_TCP, dir);
- b1 = gen_portrangeop(port1, port2, IPPROTO_UDP, dir);
- gen_or(tmp, b1);
- tmp = gen_portrangeop(port1, port2, IPPROTO_SCTP, dir);
- gen_or(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
- return b1;
-}
-
-#ifdef INET6
-static struct block *
-gen_portrangeatom6(off, v1, v2)
- int off;
- bpf_int32 v1, v2;
-{
- struct block *b1, *b2;
-
- if (v1 > v2) {
- /*
- * Reverse the order of the ports, so v1 is the lower one.
- */
- bpf_int32 vtemp;
-
- vtemp = v1;
- v1 = v2;
- v2 = vtemp;
- }
-
- b1 = gen_cmp_ge(OR_TRAN_IPV6, off, BPF_H, v1);
- b2 = gen_cmp_le(OR_TRAN_IPV6, off, BPF_H, v2);
-
- gen_and(b1, b2);
-
- return b2;
-}
-
-struct block *
-gen_portrangeop6(port1, port2, proto, dir)
- int port1, port2;
- int proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* ip6 proto 'proto' */
- b0 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)proto);
-
- switch (dir) {
- case Q_SRC:
- b1 = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
- break;
-
- case Q_DST:
- b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
- break;
-
- case Q_OR:
- case Q_DEFAULT:
- tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
- b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
- gen_or(tmp, b1);
- break;
-
- case Q_AND:
- tmp = gen_portrangeatom6(0, (bpf_int32)port1, (bpf_int32)port2);
- b1 = gen_portrangeatom6(2, (bpf_int32)port1, (bpf_int32)port2);
- gen_and(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
-
- return b1;
-}
-
-static struct block *
-gen_portrange6(port1, port2, ip_proto, dir)
- int port1, port2;
- int ip_proto;
- int dir;
-{
- struct block *b0, *b1, *tmp;
-
- /* link proto ip6 */
- b0 = gen_linktype(ETHERTYPE_IPV6);
-
- switch (ip_proto) {
- case IPPROTO_UDP:
- case IPPROTO_TCP:
- case IPPROTO_SCTP:
- b1 = gen_portrangeop6(port1, port2, ip_proto, dir);
- break;
-
- case PROTO_UNDEF:
- tmp = gen_portrangeop6(port1, port2, IPPROTO_TCP, dir);
- b1 = gen_portrangeop6(port1, port2, IPPROTO_UDP, dir);
- gen_or(tmp, b1);
- tmp = gen_portrangeop6(port1, port2, IPPROTO_SCTP, dir);
- gen_or(tmp, b1);
- break;
-
- default:
- abort();
- }
- gen_and(b0, b1);
- return b1;
-}
-#endif /* INET6 */
-
-static int
-lookup_proto(name, proto)
- register const char *name;
- register int proto;
-{
- register int v;
-
- switch (proto) {
-
- case Q_DEFAULT:
- case Q_IP:
- case Q_IPV6:
- v = pcap_nametoproto(name);
- if (v == PROTO_UNDEF)
- bpf_error("unknown ip proto '%s'", name);
- break;
-
- case Q_LINK:
- /* XXX should look up h/w protocol type based on linktype */
- v = pcap_nametoeproto(name);
- if (v == PROTO_UNDEF) {
- v = pcap_nametollc(name);
- if (v == PROTO_UNDEF)
- bpf_error("unknown ether proto '%s'", name);
- }
- break;
-
- case Q_ISO:
- if (strcmp(name, "esis") == 0)
- v = ISO9542_ESIS;
- else if (strcmp(name, "isis") == 0)
- v = ISO10589_ISIS;
- else if (strcmp(name, "clnp") == 0)
- v = ISO8473_CLNP;
- else
- bpf_error("unknown osi proto '%s'", name);
- break;
-
- default:
- v = PROTO_UNDEF;
- break;
- }
- return v;
-}
-
-#if 0
-struct stmt *
-gen_joinsp(s, n)
- struct stmt **s;
- int n;
-{
- return NULL;
-}
-#endif
-
-static struct block *
-gen_protochain(v, proto, dir)
- int v;
- int proto;
- int dir;
-{
-#ifdef NO_PROTOCHAIN
- return gen_proto(v, proto, dir);
-#else
- struct block *b0, *b;
- struct slist *s[100];
- int fix2, fix3, fix4, fix5;
- int ahcheck, again, end;
- int i, max;
- int reg2 = alloc_reg();
-
- memset(s, 0, sizeof(s));
- fix2 = fix3 = fix4 = fix5 = 0;
-
- switch (proto) {
- case Q_IP:
- case Q_IPV6:
- break;
- case Q_DEFAULT:
- b0 = gen_protochain(v, Q_IP, dir);
- b = gen_protochain(v, Q_IPV6, dir);
- gen_or(b0, b);
- return b;
- default:
- bpf_error("bad protocol applied for 'protochain'");
- /*NOTREACHED*/
- }
-
- /*
- * We don't handle variable-length radiotap here headers yet.
- * We might want to add BPF instructions to do the protochain
- * work, to simplify that and, on platforms that have a BPF
- * interpreter with the new instructions, let the filtering
- * be done in the kernel. (We already require a modified BPF
- * engine to do the protochain stuff, to support backward
- * branches, and backward branch support is unlikely to appear
- * in kernel BPF engines.)
- */
- if (linktype == DLT_IEEE802_11_RADIO)
- bpf_error("'protochain' not supported with radiotap headers");
-
- if (linktype == DLT_PPI)
- bpf_error("'protochain' not supported with PPI headers");
-
- no_optimize = 1; /*this code is not compatible with optimzer yet */
-
- /*
- * s[0] is a dummy entry to protect other BPF insn from damage
- * by s[fix] = foo with uninitialized variable "fix". It is somewhat
- * hard to find interdependency made by jump table fixup.
- */
- i = 0;
- s[i] = new_stmt(0); /*dummy*/
- i++;
-
- switch (proto) {
- case Q_IP:
- b0 = gen_linktype(ETHERTYPE_IP);
-
- /* A = ip->ip_p */
- s[i] = new_stmt(BPF_LD|BPF_ABS|BPF_B);
- s[i]->s.k = off_ll + off_nl + 9;
- i++;
- /* X = ip->ip_hl << 2 */
- s[i] = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
- s[i]->s.k = off_ll + off_nl;
- i++;
- break;
-#ifdef INET6
- case Q_IPV6:
- b0 = gen_linktype(ETHERTYPE_IPV6);
-
- /* A = ip6->ip_nxt */
- s[i] = new_stmt(BPF_LD|BPF_ABS|BPF_B);
- s[i]->s.k = off_ll + off_nl + 6;
- i++;
- /* X = sizeof(struct ip6_hdr) */
- s[i] = new_stmt(BPF_LDX|BPF_IMM);
- s[i]->s.k = 40;
- i++;
- break;
-#endif
- default:
- bpf_error("unsupported proto to gen_protochain");
- /*NOTREACHED*/
- }
-
- /* again: if (A == v) goto end; else fall through; */
- again = i;
- s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
- s[i]->s.k = v;
- s[i]->s.jt = NULL; /*later*/
- s[i]->s.jf = NULL; /*update in next stmt*/
- fix5 = i;
- i++;
-
-#ifndef IPPROTO_NONE
-#define IPPROTO_NONE 59
-#endif
- /* if (A == IPPROTO_NONE) goto end */
- s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
- s[i]->s.jt = NULL; /*later*/
- s[i]->s.jf = NULL; /*update in next stmt*/
- s[i]->s.k = IPPROTO_NONE;
- s[fix5]->s.jf = s[i];
- fix2 = i;
- i++;
-
-#ifdef INET6
- if (proto == Q_IPV6) {
- int v6start, v6end, v6advance, j;
-
- v6start = i;
- /* if (A == IPPROTO_HOPOPTS) goto v6advance */
- s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
- s[i]->s.jt = NULL; /*later*/
- s[i]->s.jf = NULL; /*update in next stmt*/
- s[i]->s.k = IPPROTO_HOPOPTS;
- s[fix2]->s.jf = s[i];
- i++;
- /* if (A == IPPROTO_DSTOPTS) goto v6advance */
- s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
- s[i]->s.jt = NULL; /*later*/
- s[i]->s.jf = NULL; /*update in next stmt*/
- s[i]->s.k = IPPROTO_DSTOPTS;
- i++;
- /* if (A == IPPROTO_ROUTING) goto v6advance */
- s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
- s[i]->s.jt = NULL; /*later*/
- s[i]->s.jf = NULL; /*update in next stmt*/
- s[i]->s.k = IPPROTO_ROUTING;
- i++;
- /* if (A == IPPROTO_FRAGMENT) goto v6advance; else goto ahcheck; */
- s[i - 1]->s.jf = s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
- s[i]->s.jt = NULL; /*later*/
- s[i]->s.jf = NULL; /*later*/
- s[i]->s.k = IPPROTO_FRAGMENT;
- fix3 = i;
- v6end = i;
- i++;
-
- /* v6advance: */
- v6advance = i;
-
- /*
- * in short,
- * A = P[X];
- * X = X + (P[X + 1] + 1) * 8;
- */
- /* A = X */
- s[i] = new_stmt(BPF_MISC|BPF_TXA);
- i++;
- /* A = P[X + packet head] */
- s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
- s[i]->s.k = off_ll + off_nl;
- i++;
- /* MEM[reg2] = A */
- s[i] = new_stmt(BPF_ST);
- s[i]->s.k = reg2;
- i++;
- /* A = X */
- s[i] = new_stmt(BPF_MISC|BPF_TXA);
- i++;
- /* A += 1 */
- s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
- s[i]->s.k = 1;
- i++;
- /* X = A */
- s[i] = new_stmt(BPF_MISC|BPF_TAX);
- i++;
- /* A = P[X + packet head]; */
- s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
- s[i]->s.k = off_ll + off_nl;
- i++;
- /* A += 1 */
- s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
- s[i]->s.k = 1;
- i++;
- /* A *= 8 */
- s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K);
- s[i]->s.k = 8;
- i++;
- /* X = A; */
- s[i] = new_stmt(BPF_MISC|BPF_TAX);
- i++;
- /* A = MEM[reg2] */
- s[i] = new_stmt(BPF_LD|BPF_MEM);
- s[i]->s.k = reg2;
- i++;
-
- /* goto again; (must use BPF_JA for backward jump) */
- s[i] = new_stmt(BPF_JMP|BPF_JA);
- s[i]->s.k = again - i - 1;
- s[i - 1]->s.jf = s[i];
- i++;
-
- /* fixup */
- for (j = v6start; j <= v6end; j++)
- s[j]->s.jt = s[v6advance];
- } else
-#endif
- {
- /* nop */
- s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
- s[i]->s.k = 0;
- s[fix2]->s.jf = s[i];
- i++;
- }
-
- /* ahcheck: */
- ahcheck = i;
- /* if (A == IPPROTO_AH) then fall through; else goto end; */
- s[i] = new_stmt(BPF_JMP|BPF_JEQ|BPF_K);
- s[i]->s.jt = NULL; /*later*/
- s[i]->s.jf = NULL; /*later*/
- s[i]->s.k = IPPROTO_AH;
- if (fix3)
- s[fix3]->s.jf = s[ahcheck];
- fix4 = i;
- i++;
-
- /*
- * in short,
- * A = P[X];
- * X = X + (P[X + 1] + 2) * 4;
- */
- /* A = X */
- s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA);
- i++;
- /* A = P[X + packet head]; */
- s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
- s[i]->s.k = off_ll + off_nl;
- i++;
- /* MEM[reg2] = A */
- s[i] = new_stmt(BPF_ST);
- s[i]->s.k = reg2;
- i++;
- /* A = X */
- s[i - 1]->s.jt = s[i] = new_stmt(BPF_MISC|BPF_TXA);
- i++;
- /* A += 1 */
- s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
- s[i]->s.k = 1;
- i++;
- /* X = A */
- s[i] = new_stmt(BPF_MISC|BPF_TAX);
- i++;
- /* A = P[X + packet head] */
- s[i] = new_stmt(BPF_LD|BPF_IND|BPF_B);
- s[i]->s.k = off_ll + off_nl;
- i++;
- /* A += 2 */
- s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
- s[i]->s.k = 2;
- i++;
- /* A *= 4 */
- s[i] = new_stmt(BPF_ALU|BPF_MUL|BPF_K);
- s[i]->s.k = 4;
- i++;
- /* X = A; */
- s[i] = new_stmt(BPF_MISC|BPF_TAX);
- i++;
- /* A = MEM[reg2] */
- s[i] = new_stmt(BPF_LD|BPF_MEM);
- s[i]->s.k = reg2;
- i++;
-
- /* goto again; (must use BPF_JA for backward jump) */
- s[i] = new_stmt(BPF_JMP|BPF_JA);
- s[i]->s.k = again - i - 1;
- i++;
-
- /* end: nop */
- end = i;
- s[i] = new_stmt(BPF_ALU|BPF_ADD|BPF_K);
- s[i]->s.k = 0;
- s[fix2]->s.jt = s[end];
- s[fix4]->s.jf = s[end];
- s[fix5]->s.jt = s[end];
- i++;
-
- /*
- * make slist chain
- */
- max = i;
- for (i = 0; i < max - 1; i++)
- s[i]->next = s[i + 1];
- s[max - 1]->next = NULL;
-
- /*
- * emit final check
- */
- b = new_block(JMP(BPF_JEQ));
- b->stmts = s[1]; /*remember, s[0] is dummy*/
- b->s.k = v;
-
- free_reg(reg2);
-
- gen_and(b0, b);
- return b;
-#endif
-}
-
-
-/*
- * Generate code that checks whether the packet is a packet for protocol
- * <proto> and whether the type field in that protocol's header has
- * the value <v>, e.g. if <proto> is Q_IP, it checks whether it's an
- * IP packet and checks the protocol number in the IP header against <v>.
- *
- * If <proto> is Q_DEFAULT, i.e. just "proto" was specified, it checks
- * against Q_IP and Q_IPV6.
- */
-static struct block *
-gen_proto(v, proto, dir)
- int v;
- int proto;
- int dir;
-{
- struct block *b0, *b1;
-
- if (dir != Q_DEFAULT)
- bpf_error("direction applied to 'proto'");
-
- switch (proto) {
- case Q_DEFAULT:
-#ifdef INET6
- b0 = gen_proto(v, Q_IP, dir);
- b1 = gen_proto(v, Q_IPV6, dir);
- gen_or(b0, b1);
- return b1;
-#else
- /*FALLTHROUGH*/
-#endif
- case Q_IP:
- /*
- * For FDDI, RFC 1188 says that SNAP encapsulation is used,
- * not LLC encapsulation with LLCSAP_IP.
- *
- * For IEEE 802 networks - which includes 802.5 token ring
- * (which is what DLT_IEEE802 means) and 802.11 - RFC 1042
- * says that SNAP encapsulation is used, not LLC encapsulation
- * with LLCSAP_IP.
- *
- * For LLC-encapsulated ATM/"Classical IP", RFC 1483 and
- * RFC 2225 say that SNAP encapsulation is used, not LLC
- * encapsulation with LLCSAP_IP.
- *
- * So we always check for ETHERTYPE_IP.
- */
- b0 = gen_linktype(ETHERTYPE_IP);
-#ifndef CHASE_CHAIN
- b1 = gen_cmp(OR_NET, 9, BPF_B, (bpf_int32)v);
-#else
- b1 = gen_protochain(v, Q_IP);
-#endif
- gen_and(b0, b1);
- return b1;
-
- case Q_ISO:
- switch (linktype) {
-
- case DLT_FRELAY:
- /*
- * Frame Relay packets typically have an OSI
- * NLPID at the beginning; "gen_linktype(LLCSAP_ISONS)"
- * generates code to check for all the OSI
- * NLPIDs, so calling it and then adding a check
- * for the particular NLPID for which we're
- * looking is bogus, as we can just check for
- * the NLPID.
- *
- * What we check for is the NLPID and a frame
- * control field value of UI, i.e. 0x03 followed
- * by the NLPID.
- *
- * XXX - assumes a 2-byte Frame Relay header with
- * DLCI and flags. What if the address is longer?
- *
- * XXX - what about SNAP-encapsulated frames?
- */
- return gen_cmp(OR_LINK, 2, BPF_H, (0x03<<8) | v);
- /*NOTREACHED*/
- break;
-
- case DLT_C_HDLC:
- /*
- * Cisco uses an Ethertype lookalike - for OSI,
- * it's 0xfefe.
- */
- b0 = gen_linktype(LLCSAP_ISONS<<8 | LLCSAP_ISONS);
- /* OSI in C-HDLC is stuffed with a fudge byte */
- b1 = gen_cmp(OR_NET_NOSNAP, 1, BPF_B, (long)v);
- gen_and(b0, b1);
- return b1;
-
- default:
- b0 = gen_linktype(LLCSAP_ISONS);
- b1 = gen_cmp(OR_NET_NOSNAP, 0, BPF_B, (long)v);
- gen_and(b0, b1);
- return b1;
- }
-
- case Q_ISIS:
- b0 = gen_proto(ISO10589_ISIS, Q_ISO, Q_DEFAULT);
- /*
- * 4 is the offset of the PDU type relative to the IS-IS
- * header.
- */
- b1 = gen_cmp(OR_NET_NOSNAP, 4, BPF_B, (long)v);
- gen_and(b0, b1);
- return b1;
-
- case Q_ARP:
- bpf_error("arp does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_RARP:
- bpf_error("rarp does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_ATALK:
- bpf_error("atalk encapsulation is not specifiable");
- /* NOTREACHED */
-
- case Q_DECNET:
- bpf_error("decnet encapsulation is not specifiable");
- /* NOTREACHED */
-
- case Q_SCA:
- bpf_error("sca does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_LAT:
- bpf_error("lat does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_MOPRC:
- bpf_error("moprc does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_MOPDL:
- bpf_error("mopdl does not encapsulate another protocol");
- /* NOTREACHED */
-
- case Q_LINK:
- return gen_linktype(v);
-
- case Q_UDP:
- bpf_error("'udp proto' is bogus");
- /* NOTREACHED */
-
- case Q_TCP:
- bpf_error("'tcp proto' is bogus");
- /* NOTREACHED */
-
- case Q_SCTP:
- bpf_error("'sctp proto' is bogus");
- /* NOTREACHED */
-
- case Q_ICMP:
- bpf_error("'icmp proto' is bogus");
- /* NOTREACHED */
-
- case Q_IGMP:
- bpf_error("'igmp proto' is bogus");
- /* NOTREACHED */
-
- case Q_IGRP:
- bpf_error("'igrp proto' is bogus");
- /* NOTREACHED */
-
- case Q_PIM:
- bpf_error("'pim proto' is bogus");
- /* NOTREACHED */
-
- case Q_VRRP:
- bpf_error("'vrrp proto' is bogus");
- /* NOTREACHED */
-
-#ifdef INET6
- case Q_IPV6:
- b0 = gen_linktype(ETHERTYPE_IPV6);
-#ifndef CHASE_CHAIN
- b1 = gen_cmp(OR_NET, 6, BPF_B, (bpf_int32)v);
-#else
- b1 = gen_protochain(v, Q_IPV6);
-#endif
- gen_and(b0, b1);
- return b1;
-
- case Q_ICMPV6:
- bpf_error("'icmp6 proto' is bogus");
-#endif /* INET6 */
-
- case Q_AH:
- bpf_error("'ah proto' is bogus");
-
- case Q_ESP:
- bpf_error("'ah proto' is bogus");
-
- case Q_STP:
- bpf_error("'stp proto' is bogus");
-
- case Q_IPX:
- bpf_error("'ipx proto' is bogus");
-
- case Q_NETBEUI:
- bpf_error("'netbeui proto' is bogus");
-
- case Q_RADIO:
- bpf_error("'radio proto' is bogus");
-
- default:
- abort();
- /* NOTREACHED */
- }
- /* NOTREACHED */
-}
-
-struct block *
-gen_scode(name, q)
- register const char *name;
- struct qual q;
-{
- int proto = q.proto;
- int dir = q.dir;
- int tproto;
- u_char *eaddr;
- bpf_u_int32 mask, addr;
-#ifndef INET6
- bpf_u_int32 **alist;
-#else
- int tproto6;
- struct sockaddr_in *sin4;
- struct sockaddr_in6 *sin6;
- struct addrinfo *res, *res0;
- struct in6_addr mask128;
-#endif /*INET6*/
- struct block *b, *tmp;
- int port, real_proto;
- int port1, port2;
-
- switch (q.addr) {
-
- case Q_NET:
- addr = pcap_nametonetaddr(name);
- if (addr == 0)
- bpf_error("unknown network '%s'", name);
- /* Left justify network addr and calculate its network mask */
- mask = 0xffffffff;
- while (addr && (addr & 0xff000000) == 0) {
- addr <<= 8;
- mask <<= 8;
- }
- return gen_host(addr, mask, proto, dir, q.addr);
-
- case Q_DEFAULT:
- case Q_HOST:
- if (proto == Q_LINK) {
- switch (linktype) {
-
- case DLT_EN10MB:
- eaddr = pcap_ether_hostton(name);
- if (eaddr == NULL)
- bpf_error(
- "unknown ether host '%s'", name);
- b = gen_ehostop(eaddr, dir);
- free(eaddr);
- return b;
-
- case DLT_FDDI:
- eaddr = pcap_ether_hostton(name);
- if (eaddr == NULL)
- bpf_error(
- "unknown FDDI host '%s'", name);
- b = gen_fhostop(eaddr, dir);
- free(eaddr);
- return b;
-
- case DLT_IEEE802:
- eaddr = pcap_ether_hostton(name);
- if (eaddr == NULL)
- bpf_error(
- "unknown token ring host '%s'", name);
- b = gen_thostop(eaddr, dir);
- free(eaddr);
- return b;
-
- case DLT_IEEE802_11:
- case DLT_IEEE802_11_RADIO_AVS:
- case DLT_IEEE802_11_RADIO:
- case DLT_PRISM_HEADER:
- case DLT_PPI:
- eaddr = pcap_ether_hostton(name);
- if (eaddr == NULL)
- bpf_error(
- "unknown 802.11 host '%s'", name);
- b = gen_wlanhostop(eaddr, dir);
- free(eaddr);
- return b;
-
- case DLT_IP_OVER_FC:
- eaddr = pcap_ether_hostton(name);
- if (eaddr == NULL)
- bpf_error(
- "unknown Fibre Channel host '%s'", name);
- b = gen_ipfchostop(eaddr, dir);
- free(eaddr);
- return b;
-
- case DLT_SUNATM:
- if (!is_lane)
- break;
-
- /*
- * Check that the packet doesn't begin
- * with an LE Control marker. (We've
- * already generated a test for LANE.)
- */
- tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS,
- BPF_H, 0xFF00);
- gen_not(tmp);
-
- eaddr = pcap_ether_hostton(name);
- if (eaddr == NULL)
- bpf_error(
- "unknown ether host '%s'", name);
- b = gen_ehostop(eaddr, dir);
- gen_and(tmp, b);
- free(eaddr);
- return b;
- }
-
- bpf_error("only ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel supports link-level host name");
- } else if (proto == Q_DECNET) {
- unsigned short dn_addr = __pcap_nametodnaddr(name);
- /*
- * I don't think DECNET hosts can be multihomed, so
- * there is no need to build up a list of addresses
- */
- return (gen_host(dn_addr, 0, proto, dir, q.addr));
- } else {
-#ifndef INET6
- alist = pcap_nametoaddr(name);
- if (alist == NULL || *alist == NULL)
- bpf_error("unknown host '%s'", name);
- tproto = proto;
- if (off_linktype == (u_int)-1 && tproto == Q_DEFAULT)
- tproto = Q_IP;
- b = gen_host(**alist++, 0xffffffff, tproto, dir, q.addr);
- while (*alist) {
- tmp = gen_host(**alist++, 0xffffffff,
- tproto, dir, q.addr);
- gen_or(b, tmp);
- b = tmp;
- }
- return b;
-#else
- memset(&mask128, 0xff, sizeof(mask128));
- res0 = res = pcap_nametoaddrinfo(name);
- if (res == NULL)
- bpf_error("unknown host '%s'", name);
- b = tmp = NULL;
- tproto = tproto6 = proto;
- if (off_linktype == -1 && tproto == Q_DEFAULT) {
- tproto = Q_IP;
- tproto6 = Q_IPV6;
- }
- for (res = res0; res; res = res->ai_next) {
- switch (res->ai_family) {
- case AF_INET:
- if (tproto == Q_IPV6)
- continue;
-
- sin4 = (struct sockaddr_in *)
- res->ai_addr;
- tmp = gen_host(ntohl(sin4->sin_addr.s_addr),
- 0xffffffff, tproto, dir, q.addr);
- break;
- case AF_INET6:
- if (tproto6 == Q_IP)
- continue;
-
- sin6 = (struct sockaddr_in6 *)
- res->ai_addr;
- tmp = gen_host6(&sin6->sin6_addr,
- &mask128, tproto6, dir, q.addr);
- break;
- default:
- continue;
- }
- if (b)
- gen_or(b, tmp);
- b = tmp;
- }
- freeaddrinfo(res0);
- if (b == NULL) {
- bpf_error("unknown host '%s'%s", name,
- (proto == Q_DEFAULT)
- ? ""
- : " for specified address family");
- }
- return b;
-#endif /*INET6*/
- }
-
- case Q_PORT:
- if (proto != Q_DEFAULT &&
- proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP)
- bpf_error("illegal qualifier of 'port'");
- if (pcap_nametoport(name, &port, &real_proto) == 0)
- bpf_error("unknown port '%s'", name);
- if (proto == Q_UDP) {
- if (real_proto == IPPROTO_TCP)
- bpf_error("port '%s' is tcp", name);
- else if (real_proto == IPPROTO_SCTP)
- bpf_error("port '%s' is sctp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_UDP;
- }
- if (proto == Q_TCP) {
- if (real_proto == IPPROTO_UDP)
- bpf_error("port '%s' is udp", name);
-
- else if (real_proto == IPPROTO_SCTP)
- bpf_error("port '%s' is sctp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_TCP;
- }
- if (proto == Q_SCTP) {
- if (real_proto == IPPROTO_UDP)
- bpf_error("port '%s' is udp", name);
-
- else if (real_proto == IPPROTO_TCP)
- bpf_error("port '%s' is tcp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_SCTP;
- }
-#ifndef INET6
- return gen_port(port, real_proto, dir);
-#else
- b = gen_port(port, real_proto, dir);
- gen_or(gen_port6(port, real_proto, dir), b);
- return b;
-#endif /* INET6 */
-
- case Q_PORTRANGE:
- if (proto != Q_DEFAULT &&
- proto != Q_UDP && proto != Q_TCP && proto != Q_SCTP)
- bpf_error("illegal qualifier of 'portrange'");
- if (pcap_nametoportrange(name, &port1, &port2, &real_proto) == 0)
- bpf_error("unknown port in range '%s'", name);
- if (proto == Q_UDP) {
- if (real_proto == IPPROTO_TCP)
- bpf_error("port in range '%s' is tcp", name);
- else if (real_proto == IPPROTO_SCTP)
- bpf_error("port in range '%s' is sctp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_UDP;
- }
- if (proto == Q_TCP) {
- if (real_proto == IPPROTO_UDP)
- bpf_error("port in range '%s' is udp", name);
- else if (real_proto == IPPROTO_SCTP)
- bpf_error("port in range '%s' is sctp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_TCP;
- }
- if (proto == Q_SCTP) {
- if (real_proto == IPPROTO_UDP)
- bpf_error("port in range '%s' is udp", name);
- else if (real_proto == IPPROTO_TCP)
- bpf_error("port in range '%s' is tcp", name);
- else
- /* override PROTO_UNDEF */
- real_proto = IPPROTO_SCTP;
- }
-#ifndef INET6
- return gen_portrange(port1, port2, real_proto, dir);
-#else
- b = gen_portrange(port1, port2, real_proto, dir);
- gen_or(gen_portrange6(port1, port2, real_proto, dir), b);
- return b;
-#endif /* INET6 */
-
- case Q_GATEWAY:
-#ifndef INET6
- eaddr = pcap_ether_hostton(name);
- if (eaddr == NULL)
- bpf_error("unknown ether host: %s", name);
-
- alist = pcap_nametoaddr(name);
- if (alist == NULL || *alist == NULL)
- bpf_error("unknown host '%s'", name);
- b = gen_gateway(eaddr, alist, proto, dir);
- free(eaddr);
- return b;
-#else
- bpf_error("'gateway' not supported in this configuration");
-#endif /*INET6*/
-
- case Q_PROTO:
- real_proto = lookup_proto(name, proto);
- if (real_proto >= 0)
- return gen_proto(real_proto, proto, dir);
- else
- bpf_error("unknown protocol: %s", name);
-
- case Q_PROTOCHAIN:
- real_proto = lookup_proto(name, proto);
- if (real_proto >= 0)
- return gen_protochain(real_proto, proto, dir);
- else
- bpf_error("unknown protocol: %s", name);
-
-
- case Q_UNDEF:
- syntax();
- /* NOTREACHED */
- }
- abort();
- /* NOTREACHED */
-}
-
-struct block *
-gen_mcode(s1, s2, masklen, q)
- register const char *s1, *s2;
- register int masklen;
- struct qual q;
-{
- register int nlen, mlen;
- bpf_u_int32 n, m;
-
- nlen = __pcap_atoin(s1, &n);
- /* Promote short ipaddr */
- n <<= 32 - nlen;
-
- if (s2 != NULL) {
- mlen = __pcap_atoin(s2, &m);
- /* Promote short ipaddr */
- m <<= 32 - mlen;
- if ((n & ~m) != 0)
- bpf_error("non-network bits set in \"%s mask %s\"",
- s1, s2);
- } else {
- /* Convert mask len to mask */
- if (masklen > 32)
- bpf_error("mask length must be <= 32");
- if (masklen == 0) {
- /*
- * X << 32 is not guaranteed by C to be 0; it's
- * undefined.
- */
- m = 0;
- } else
- m = 0xffffffff << (32 - masklen);
- if ((n & ~m) != 0)
- bpf_error("non-network bits set in \"%s/%d\"",
- s1, masklen);
- }
-
- switch (q.addr) {
-
- case Q_NET:
- return gen_host(n, m, q.proto, q.dir, q.addr);
-
- default:
- bpf_error("Mask syntax for networks only");
- /* NOTREACHED */
- }
- /* NOTREACHED */
- return NULL;
-}
-
-struct block *
-gen_ncode(s, v, q)
- register const char *s;
- bpf_u_int32 v;
- struct qual q;
-{
- bpf_u_int32 mask;
- int proto = q.proto;
- int dir = q.dir;
- register int vlen;
-
- if (s == NULL)
- vlen = 32;
- else if (q.proto == Q_DECNET)
- vlen = __pcap_atodn(s, &v);
- else
- vlen = __pcap_atoin(s, &v);
-
- switch (q.addr) {
-
- case Q_DEFAULT:
- case Q_HOST:
- case Q_NET:
- if (proto == Q_DECNET)
- return gen_host(v, 0, proto, dir, q.addr);
- else if (proto == Q_LINK) {
- bpf_error("illegal link layer address");
- } else {
- mask = 0xffffffff;
- if (s == NULL && q.addr == Q_NET) {
- /* Promote short net number */
- while (v && (v & 0xff000000) == 0) {
- v <<= 8;
- mask <<= 8;
- }
- } else {
- /* Promote short ipaddr */
- v <<= 32 - vlen;
- mask <<= 32 - vlen;
- }
- return gen_host(v, mask, proto, dir, q.addr);
- }
-
- case Q_PORT:
- if (proto == Q_UDP)
- proto = IPPROTO_UDP;
- else if (proto == Q_TCP)
- proto = IPPROTO_TCP;
- else if (proto == Q_SCTP)
- proto = IPPROTO_SCTP;
- else if (proto == Q_DEFAULT)
- proto = PROTO_UNDEF;
- else
- bpf_error("illegal qualifier of 'port'");
-
-#ifndef INET6
- return gen_port((int)v, proto, dir);
-#else
- {
- struct block *b;
- b = gen_port((int)v, proto, dir);
- gen_or(gen_port6((int)v, proto, dir), b);
- return b;
- }
-#endif /* INET6 */
-
- case Q_PORTRANGE:
- if (proto == Q_UDP)
- proto = IPPROTO_UDP;
- else if (proto == Q_TCP)
- proto = IPPROTO_TCP;
- else if (proto == Q_SCTP)
- proto = IPPROTO_SCTP;
- else if (proto == Q_DEFAULT)
- proto = PROTO_UNDEF;
- else
- bpf_error("illegal qualifier of 'portrange'");
-
-#ifndef INET6
- return gen_portrange((int)v, (int)v, proto, dir);
-#else
- {
- struct block *b;
- b = gen_portrange((int)v, (int)v, proto, dir);
- gen_or(gen_portrange6((int)v, (int)v, proto, dir), b);
- return b;
- }
-#endif /* INET6 */
-
- case Q_GATEWAY:
- bpf_error("'gateway' requires a name");
- /* NOTREACHED */
-
- case Q_PROTO:
- return gen_proto((int)v, proto, dir);
-
- case Q_PROTOCHAIN:
- return gen_protochain((int)v, proto, dir);
-
- case Q_UNDEF:
- syntax();
- /* NOTREACHED */
-
- default:
- abort();
- /* NOTREACHED */
- }
- /* NOTREACHED */
-}
-
-#ifdef INET6
-struct block *
-gen_mcode6(s1, s2, masklen, q)
- register const char *s1, *s2;
- register int masklen;
- struct qual q;
-{
- struct addrinfo *res;
- struct in6_addr *addr;
- struct in6_addr mask;
- struct block *b;
- u_int32_t *a, *m;
-
- if (s2)
- bpf_error("no mask %s supported", s2);
-
- res = pcap_nametoaddrinfo(s1);
- if (!res)
- bpf_error("invalid ip6 address %s", s1);
- if (res->ai_next)
- bpf_error("%s resolved to multiple address", s1);
- addr = &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr;
-
- if (sizeof(mask) * 8 < masklen)
- bpf_error("mask length must be <= %u", (unsigned int)(sizeof(mask) * 8));
- memset(&mask, 0, sizeof(mask));
- memset(&mask, 0xff, masklen / 8);
- if (masklen % 8) {
- mask.s6_addr[masklen / 8] =
- (0xff << (8 - masklen % 8)) & 0xff;
- }
-
- a = (u_int32_t *)addr;
- m = (u_int32_t *)&mask;
- if ((a[0] & ~m[0]) || (a[1] & ~m[1])
- || (a[2] & ~m[2]) || (a[3] & ~m[3])) {
- bpf_error("non-network bits set in \"%s/%d\"", s1, masklen);
- }
-
- switch (q.addr) {
-
- case Q_DEFAULT:
- case Q_HOST:
- if (masklen != 128)
- bpf_error("Mask syntax for networks only");
- /* FALLTHROUGH */
-
- case Q_NET:
- b = gen_host6(addr, &mask, q.proto, q.dir, q.addr);
- freeaddrinfo(res);
- return b;
-
- default:
- bpf_error("invalid qualifier against IPv6 address");
- /* NOTREACHED */
- }
- return NULL;
-}
-#endif /*INET6*/
-
-struct block *
-gen_ecode(eaddr, q)
- register const u_char *eaddr;
- struct qual q;
-{
- struct block *b, *tmp;
-
- if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) {
- switch (linktype) {
- case DLT_EN10MB:
- return gen_ehostop(eaddr, (int)q.dir);
- case DLT_FDDI:
- return gen_fhostop(eaddr, (int)q.dir);
- case DLT_IEEE802:
- return gen_thostop(eaddr, (int)q.dir);
- case DLT_IEEE802_11:
- case DLT_IEEE802_11_RADIO_AVS:
- case DLT_IEEE802_11_RADIO:
- case DLT_PRISM_HEADER:
- case DLT_PPI:
- return gen_wlanhostop(eaddr, (int)q.dir);
- case DLT_SUNATM:
- if (is_lane) {
- /*
- * Check that the packet doesn't begin with an
- * LE Control marker. (We've already generated
- * a test for LANE.)
- */
- tmp = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
- 0xFF00);
- gen_not(tmp);
-
- /*
- * Now check the MAC address.
- */
- b = gen_ehostop(eaddr, (int)q.dir);
- gen_and(tmp, b);
- return b;
- }
- break;
- case DLT_IP_OVER_FC:
- return gen_ipfchostop(eaddr, (int)q.dir);
- default:
- bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
- break;
- }
- }
- bpf_error("ethernet address used in non-ether expression");
- /* NOTREACHED */
- return NULL;
-}
-
-void
-sappend(s0, s1)
- struct slist *s0, *s1;
-{
- /*
- * This is definitely not the best way to do this, but the
- * lists will rarely get long.
- */
- while (s0->next)
- s0 = s0->next;
- s0->next = s1;
-}
-
-static struct slist *
-xfer_to_x(a)
- struct arth *a;
-{
- struct slist *s;
-
- s = new_stmt(BPF_LDX|BPF_MEM);
- s->s.k = a->regno;
- return s;
-}
-
-static struct slist *
-xfer_to_a(a)
- struct arth *a;
-{
- struct slist *s;
-
- s = new_stmt(BPF_LD|BPF_MEM);
- s->s.k = a->regno;
- return s;
-}
-
-/*
- * Modify "index" to use the value stored into its register as an
- * offset relative to the beginning of the header for the protocol
- * "proto", and allocate a register and put an item "size" bytes long
- * (1, 2, or 4) at that offset into that register, making it the register
- * for "index".
- */
-struct arth *
-gen_load(proto, inst, size)
- int proto;
- struct arth *inst;
- int size;
-{
- struct slist *s, *tmp;
- struct block *b;
- int regno = alloc_reg();
-
- free_reg(inst->regno);
- switch (size) {
-
- default:
- bpf_error("data size must be 1, 2, or 4");
-
- case 1:
- size = BPF_B;
- break;
-
- case 2:
- size = BPF_H;
- break;
-
- case 4:
- size = BPF_W;
- break;
- }
- switch (proto) {
- default:
- bpf_error("unsupported index operation");
-
- case Q_RADIO:
- /*
- * The offset is relative to the beginning of the packet
- * data, if we have a radio header. (If we don't, this
- * is an error.)
- */
- if (linktype != DLT_IEEE802_11_RADIO_AVS &&
- linktype != DLT_IEEE802_11_RADIO &&
- linktype != DLT_PRISM_HEADER)
- bpf_error("radio information not present in capture");
-
- /*
- * Load into the X register the offset computed into the
- * register specifed by "index".
- */
- s = xfer_to_x(inst);
-
- /*
- * Load the item at that offset.
- */
- tmp = new_stmt(BPF_LD|BPF_IND|size);
- sappend(s, tmp);
- sappend(inst->s, s);
- break;
-
- case Q_LINK:
- /*
- * The offset is relative to the beginning of
- * the link-layer header.
- *
- * XXX - what about ATM LANE? Should the index be
- * relative to the beginning of the AAL5 frame, so
- * that 0 refers to the beginning of the LE Control
- * field, or relative to the beginning of the LAN
- * frame, so that 0 refers, for Ethernet LANE, to
- * the beginning of the destination address?
- */
- s = gen_llprefixlen();
-
- /*
- * If "s" is non-null, it has code to arrange that the
- * X register contains the length of the prefix preceding
- * the link-layer header. Add to it the offset computed
- * into the register specified by "index", and move that
- * into the X register. Otherwise, just load into the X
- * register the offset computed into the register specifed
- * by "index".
- */
- if (s != NULL) {
- sappend(s, xfer_to_a(inst));
- sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
- sappend(s, new_stmt(BPF_MISC|BPF_TAX));
- } else
- s = xfer_to_x(inst);
-
- /*
- * Load the item at the sum of the offset we've put in the
- * X register and the offset of the start of the link
- * layer header (which is 0 if the radio header is
- * variable-length; that header length is what we put
- * into the X register and then added to the index).
- */
- tmp = new_stmt(BPF_LD|BPF_IND|size);
- tmp->s.k = off_ll;
- sappend(s, tmp);
- sappend(inst->s, s);
- break;
-
- case Q_IP:
- case Q_ARP:
- case Q_RARP:
- case Q_ATALK:
- case Q_DECNET:
- case Q_SCA:
- case Q_LAT:
- case Q_MOPRC:
- case Q_MOPDL:
-#ifdef INET6
- case Q_IPV6:
-#endif
- /*
- * The offset is relative to the beginning of
- * the network-layer header.
- * XXX - are there any cases where we want
- * off_nl_nosnap?
- */
- s = gen_llprefixlen();
-
- /*
- * If "s" is non-null, it has code to arrange that the
- * X register contains the length of the prefix preceding
- * the link-layer header. Add to it the offset computed
- * into the register specified by "index", and move that
- * into the X register. Otherwise, just load into the X
- * register the offset computed into the register specifed
- * by "index".
- */
- if (s != NULL) {
- sappend(s, xfer_to_a(inst));
- sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
- sappend(s, new_stmt(BPF_MISC|BPF_TAX));
- } else
- s = xfer_to_x(inst);
-
- /*
- * Load the item at the sum of the offset we've put in the
- * X register, the offset of the start of the network
- * layer header, and the offset of the start of the link
- * layer header (which is 0 if the radio header is
- * variable-length; that header length is what we put
- * into the X register and then added to the index).
- */
- tmp = new_stmt(BPF_LD|BPF_IND|size);
- tmp->s.k = off_ll + off_nl;
- sappend(s, tmp);
- sappend(inst->s, s);
-
- /*
- * Do the computation only if the packet contains
- * the protocol in question.
- */
- b = gen_proto_abbrev(proto);
- if (inst->b)
- gen_and(inst->b, b);
- inst->b = b;
- break;
-
- case Q_SCTP:
- case Q_TCP:
- case Q_UDP:
- case Q_ICMP:
- case Q_IGMP:
- case Q_IGRP:
- case Q_PIM:
- case Q_VRRP:
- /*
- * The offset is relative to the beginning of
- * the transport-layer header.
- *
- * Load the X register with the length of the IPv4 header
- * (plus the offset of the link-layer header, if it's
- * a variable-length header), in bytes.
- *
- * XXX - are there any cases where we want
- * off_nl_nosnap?
- * XXX - we should, if we're built with
- * IPv6 support, generate code to load either
- * IPv4, IPv6, or both, as appropriate.
- */
- s = gen_loadx_iphdrlen();
-
- /*
- * The X register now contains the sum of the length
- * of any variable-length header preceding the link-layer
- * header and the length of the network-layer header.
- * Load into the A register the offset relative to
- * the beginning of the transport layer header,
- * add the X register to that, move that to the
- * X register, and load with an offset from the
- * X register equal to the offset of the network
- * layer header relative to the beginning of
- * the link-layer header plus the length of any
- * fixed-length header preceding the link-layer
- * header.
- */
- sappend(s, xfer_to_a(inst));
- sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
- sappend(s, new_stmt(BPF_MISC|BPF_TAX));
- sappend(s, tmp = new_stmt(BPF_LD|BPF_IND|size));
- tmp->s.k = off_ll + off_nl;
- sappend(inst->s, s);
-
- /*
- * Do the computation only if the packet contains
- * the protocol in question - which is true only
- * if this is an IP datagram and is the first or
- * only fragment of that datagram.
- */
- gen_and(gen_proto_abbrev(proto), b = gen_ipfrag());
- if (inst->b)
- gen_and(inst->b, b);
-#ifdef INET6
- gen_and(gen_proto_abbrev(Q_IP), b);
-#endif
- inst->b = b;
- break;
-#ifdef INET6
- case Q_ICMPV6:
- bpf_error("IPv6 upper-layer protocol is not supported by proto[x]");
- /*NOTREACHED*/
-#endif
- }
- inst->regno = regno;
- s = new_stmt(BPF_ST);
- s->s.k = regno;
- sappend(inst->s, s);
-
- return inst;
-}
-
-struct block *
-gen_relation(code, a0, a1, reversed)
- int code;
- struct arth *a0, *a1;
- int reversed;
-{
- struct slist *s0, *s1, *s2;
- struct block *b, *tmp;
-
- s0 = xfer_to_x(a1);
- s1 = xfer_to_a(a0);
- if (code == BPF_JEQ) {
- s2 = new_stmt(BPF_ALU|BPF_SUB|BPF_X);
- b = new_block(JMP(code));
- sappend(s1, s2);
- }
- else
- b = new_block(BPF_JMP|code|BPF_X);
- if (reversed)
- gen_not(b);
-
- sappend(s0, s1);
- sappend(a1->s, s0);
- sappend(a0->s, a1->s);
-
- b->stmts = a0->s;
-
- free_reg(a0->regno);
- free_reg(a1->regno);
-
- /* 'and' together protocol checks */
- if (a0->b) {
- if (a1->b) {
- gen_and(a0->b, tmp = a1->b);
- }
- else
- tmp = a0->b;
- } else
- tmp = a1->b;
-
- if (tmp)
- gen_and(tmp, b);
-
- return b;
-}
-
-struct arth *
-gen_loadlen()
-{
- int regno = alloc_reg();
- struct arth *a = (struct arth *)newchunk(sizeof(*a));
- struct slist *s;
-
- s = new_stmt(BPF_LD|BPF_LEN);
- s->next = new_stmt(BPF_ST);
- s->next->s.k = regno;
- a->s = s;
- a->regno = regno;
-
- return a;
-}
-
-struct arth *
-gen_loadi(val)
- int val;
-{
- struct arth *a;
- struct slist *s;
- int reg;
-
- a = (struct arth *)newchunk(sizeof(*a));
-
- reg = alloc_reg();
-
- s = new_stmt(BPF_LD|BPF_IMM);
- s->s.k = val;
- s->next = new_stmt(BPF_ST);
- s->next->s.k = reg;
- a->s = s;
- a->regno = reg;
-
- return a;
-}
-
-struct arth *
-gen_neg(a)
- struct arth *a;
-{
- struct slist *s;
-
- s = xfer_to_a(a);
- sappend(a->s, s);
- s = new_stmt(BPF_ALU|BPF_NEG);
- s->s.k = 0;
- sappend(a->s, s);
- s = new_stmt(BPF_ST);
- s->s.k = a->regno;
- sappend(a->s, s);
-
- return a;
-}
-
-struct arth *
-gen_arth(code, a0, a1)
- int code;
- struct arth *a0, *a1;
-{
- struct slist *s0, *s1, *s2;
-
- s0 = xfer_to_x(a1);
- s1 = xfer_to_a(a0);
- s2 = new_stmt(BPF_ALU|BPF_X|code);
-
- sappend(s1, s2);
- sappend(s0, s1);
- sappend(a1->s, s0);
- sappend(a0->s, a1->s);
-
- free_reg(a0->regno);
- free_reg(a1->regno);
-
- s0 = new_stmt(BPF_ST);
- a0->regno = s0->s.k = alloc_reg();
- sappend(a0->s, s0);
-
- return a0;
-}
-
-/*
- * Here we handle simple allocation of the scratch registers.
- * If too many registers are alloc'd, the allocator punts.
- */
-static int regused[BPF_MEMWORDS];
-static int curreg;
-
-/*
- * Return the next free register.
- */
-static int
-alloc_reg()
-{
- int n = BPF_MEMWORDS;
-
- while (--n >= 0) {
- if (regused[curreg])
- curreg = (curreg + 1) % BPF_MEMWORDS;
- else {
- regused[curreg] = 1;
- return curreg;
- }
- }
- bpf_error("too many registers needed to evaluate expression");
- /* NOTREACHED */
- return 0;
-}
-
-/*
- * Return a register to the table so it can
- * be used later.
- */
-static void
-free_reg(n)
- int n;
-{
- regused[n] = 0;
-}
-
-static struct block *
-gen_len(jmp, n)
- int jmp, n;
-{
- struct slist *s;
- struct block *b;
-
- s = new_stmt(BPF_LD|BPF_LEN);
- b = new_block(JMP(jmp));
- b->stmts = s;
- b->s.k = n;
-
- return b;
-}
-
-struct block *
-gen_greater(n)
- int n;
-{
- return gen_len(BPF_JGE, n);
-}
-
-/*
- * Actually, this is less than or equal.
- */
-struct block *
-gen_less(n)
- int n;
-{
- struct block *b;
-
- b = gen_len(BPF_JGT, n);
- gen_not(b);
-
- return b;
-}
-
-/*
- * This is for "byte {idx} {op} {val}"; "idx" is treated as relative to
- * the beginning of the link-layer header.
- * XXX - that means you can't test values in the radiotap header, but
- * as that header is difficult if not impossible to parse generally
- * without a loop, that might not be a severe problem. A new keyword
- * "radio" could be added for that, although what you'd really want
- * would be a way of testing particular radio header values, which
- * would generate code appropriate to the radio header in question.
- */
-struct block *
-gen_byteop(op, idx, val)
- int op, idx, val;
-{
- struct block *b;
- struct slist *s;
-
- switch (op) {
- default:
- abort();
-
- case '=':
- return gen_cmp(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
-
- case '<':
- b = gen_cmp_lt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
- return b;
-
- case '>':
- b = gen_cmp_gt(OR_LINK, (u_int)idx, BPF_B, (bpf_int32)val);
- return b;
-
- case '|':
- s = new_stmt(BPF_ALU|BPF_OR|BPF_K);
- break;
-
- case '&':
- s = new_stmt(BPF_ALU|BPF_AND|BPF_K);
- break;
- }
- s->s.k = val;
- b = new_block(JMP(BPF_JEQ));
- b->stmts = s;
- gen_not(b);
-
- return b;
-}
-
-static u_char abroadcast[] = { 0x0 };
-
-struct block *
-gen_broadcast(proto)
- int proto;
-{
- bpf_u_int32 hostmask;
- struct block *b0, *b1, *b2;
- static u_char ebroadcast[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
-
- switch (proto) {
-
- case Q_DEFAULT:
- case Q_LINK:
- switch (linktype) {
- case DLT_ARCNET:
- case DLT_ARCNET_LINUX:
- return gen_ahostop(abroadcast, Q_DST);
- case DLT_EN10MB:
- return gen_ehostop(ebroadcast, Q_DST);
- case DLT_FDDI:
- return gen_fhostop(ebroadcast, Q_DST);
- case DLT_IEEE802:
- return gen_thostop(ebroadcast, Q_DST);
- case DLT_IEEE802_11:
- case DLT_IEEE802_11_RADIO_AVS:
- case DLT_IEEE802_11_RADIO:
- case DLT_PPI:
- case DLT_PRISM_HEADER:
- return gen_wlanhostop(ebroadcast, Q_DST);
- case DLT_IP_OVER_FC:
- return gen_ipfchostop(ebroadcast, Q_DST);
- case DLT_SUNATM:
- if (is_lane) {
- /*
- * Check that the packet doesn't begin with an
- * LE Control marker. (We've already generated
- * a test for LANE.)
- */
- b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
- 0xFF00);
- gen_not(b1);
-
- /*
- * Now check the MAC address.
- */
- b0 = gen_ehostop(ebroadcast, Q_DST);
- gen_and(b1, b0);
- return b0;
- }
- break;
- default:
- bpf_error("not a broadcast link");
- }
- break;
-
- case Q_IP:
- b0 = gen_linktype(ETHERTYPE_IP);
- hostmask = ~netmask;
- b1 = gen_mcmp(OR_NET, 16, BPF_W, (bpf_int32)0, hostmask);
- b2 = gen_mcmp(OR_NET, 16, BPF_W,
- (bpf_int32)(~0 & hostmask), hostmask);
- gen_or(b1, b2);
- gen_and(b0, b2);
- return b2;
- }
- bpf_error("only link-layer/IP broadcast filters supported");
- /* NOTREACHED */
- return NULL;
-}
-
-/*
- * Generate code to test the low-order bit of a MAC address (that's
- * the bottom bit of the *first* byte).
- */
-static struct block *
-gen_mac_multicast(offset)
- int offset;
-{
- register struct block *b0;
- register struct slist *s;
-
- /* link[offset] & 1 != 0 */
- s = gen_load_a(OR_LINK, offset, BPF_B);
- b0 = new_block(JMP(BPF_JSET));
- b0->s.k = 1;
- b0->stmts = s;
- return b0;
-}
-
-struct block *
-gen_multicast(proto)
- int proto;
-{
- register struct block *b0, *b1, *b2;
- register struct slist *s;
-
- switch (proto) {
-
- case Q_DEFAULT:
- case Q_LINK:
- switch (linktype) {
- case DLT_ARCNET:
- case DLT_ARCNET_LINUX:
- /* all ARCnet multicasts use the same address */
- return gen_ahostop(abroadcast, Q_DST);
- case DLT_EN10MB:
- /* ether[0] & 1 != 0 */
- return gen_mac_multicast(0);
- case DLT_FDDI:
- /*
- * XXX TEST THIS: MIGHT NOT PORT PROPERLY XXX
- *
- * XXX - was that referring to bit-order issues?
- */
- /* fddi[1] & 1 != 0 */
- return gen_mac_multicast(1);
- case DLT_IEEE802:
- /* tr[2] & 1 != 0 */
- return gen_mac_multicast(2);
- case DLT_IEEE802_11:
- case DLT_IEEE802_11_RADIO_AVS:
- case DLT_PPI:
- case DLT_IEEE802_11_RADIO:
- case DLT_PRISM_HEADER:
- /*
- * Oh, yuk.
- *
- * For control frames, there is no DA.
- *
- * For management frames, DA is at an
- * offset of 4 from the beginning of
- * the packet.
- *
- * For data frames, DA is at an offset
- * of 4 from the beginning of the packet
- * if To DS is clear and at an offset of
- * 16 from the beginning of the packet
- * if To DS is set.
- */
-
- /*
- * Generate the tests to be done for data frames.
- *
- * First, check for To DS set, i.e. "link[1] & 0x01".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x01; /* To DS */
- b1->stmts = s;
-
- /*
- * If To DS is set, the DA is at 16.
- */
- b0 = gen_mac_multicast(16);
- gen_and(b1, b0);
-
- /*
- * Now, check for To DS not set, i.e. check
- * "!(link[1] & 0x01)".
- */
- s = gen_load_a(OR_LINK, 1, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x01; /* To DS */
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * If To DS is not set, the DA is at 4.
- */
- b1 = gen_mac_multicast(4);
- gen_and(b2, b1);
-
- /*
- * Now OR together the last two checks. That gives
- * the complete set of checks for data frames.
- */
- gen_or(b1, b0);
-
- /*
- * Now check for a data frame.
- * I.e, check "link[0] & 0x08".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x08;
- b1->stmts = s;
-
- /*
- * AND that with the checks done for data frames.
- */
- gen_and(b1, b0);
-
- /*
- * If the high-order bit of the type value is 0, this
- * is a management frame.
- * I.e, check "!(link[0] & 0x08)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b2 = new_block(JMP(BPF_JSET));
- b2->s.k = 0x08;
- b2->stmts = s;
- gen_not(b2);
-
- /*
- * For management frames, the DA is at 4.
- */
- b1 = gen_mac_multicast(4);
- gen_and(b2, b1);
-
- /*
- * OR that with the checks done for data frames.
- * That gives the checks done for management and
- * data frames.
- */
- gen_or(b1, b0);
-
- /*
- * If the low-order bit of the type value is 1,
- * this is either a control frame or a frame
- * with a reserved type, and thus not a
- * frame with an SA.
- *
- * I.e., check "!(link[0] & 0x04)".
- */
- s = gen_load_a(OR_LINK, 0, BPF_B);
- b1 = new_block(JMP(BPF_JSET));
- b1->s.k = 0x04;
- b1->stmts = s;
- gen_not(b1);
-
- /*
- * AND that with the checks for data and management
- * frames.
- */
- gen_and(b1, b0);
- return b0;
- case DLT_IP_OVER_FC:
- b0 = gen_mac_multicast(2);
- return b0;
- case DLT_SUNATM:
- if (is_lane) {
- /*
- * Check that the packet doesn't begin with an
- * LE Control marker. (We've already generated
- * a test for LANE.)
- */
- b1 = gen_cmp(OR_LINK, SUNATM_PKT_BEGIN_POS, BPF_H,
- 0xFF00);
- gen_not(b1);
-
- /* ether[off_mac] & 1 != 0 */
- b0 = gen_mac_multicast(off_mac);
- gen_and(b1, b0);
- return b0;
- }
- break;
- default:
- break;
- }
- /* Link not known to support multicasts */
- break;
-
- case Q_IP:
- b0 = gen_linktype(ETHERTYPE_IP);
- b1 = gen_cmp_ge(OR_NET, 16, BPF_B, (bpf_int32)224);
- gen_and(b0, b1);
- return b1;
-
-#ifdef INET6
- case Q_IPV6:
- b0 = gen_linktype(ETHERTYPE_IPV6);
- b1 = gen_cmp(OR_NET, 24, BPF_B, (bpf_int32)255);
- gen_and(b0, b1);
- return b1;
-#endif /* INET6 */
- }
- bpf_error("link-layer multicast filters supported only on ethernet/FDDI/token ring/ARCNET/802.11/ATM LANE/Fibre Channel");
- /* NOTREACHED */
- return NULL;
-}
-
-/*
- * generate command for inbound/outbound. It's here so we can
- * make it link-type specific. 'dir' = 0 implies "inbound",
- * = 1 implies "outbound".
- */
-struct block *
-gen_inbound(dir)
- int dir;
-{
- register struct block *b0;
-
- /*
- * Only some data link types support inbound/outbound qualifiers.
- */
- switch (linktype) {
- case DLT_SLIP:
- b0 = gen_relation(BPF_JEQ,
- gen_load(Q_LINK, gen_loadi(0), 1),
- gen_loadi(0),
- dir);
- break;
-
- case DLT_LINUX_SLL:
- if (dir) {
- /*
- * Match packets sent by this machine.
- */
- b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_OUTGOING);
- } else {
- /*
- * Match packets sent to this machine.
- * (No broadcast or multicast packets, or
- * packets sent to some other machine and
- * received promiscuously.)
- *
- * XXX - packets sent to other machines probably
- * shouldn't be matched, but what about broadcast
- * or multicast packets we received?
- */
- b0 = gen_cmp(OR_LINK, 0, BPF_H, LINUX_SLL_HOST);
- }
- break;
-
- case DLT_PFLOG:
- b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, dir), BPF_B,
- (bpf_int32)((dir == 0) ? PF_IN : PF_OUT));
- break;
-
- case DLT_PPP_PPPD:
- if (dir) {
- /* match outgoing packets */
- b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_OUT);
- } else {
- /* match incoming packets */
- b0 = gen_cmp(OR_LINK, 0, BPF_B, PPP_PPPD_IN);
- }
- break;
-
- case DLT_JUNIPER_MFR:
- case DLT_JUNIPER_MLFR:
- case DLT_JUNIPER_MLPPP:
- case DLT_JUNIPER_ATM1:
- case DLT_JUNIPER_ATM2:
- case DLT_JUNIPER_PPPOE:
- case DLT_JUNIPER_PPPOE_ATM:
- case DLT_JUNIPER_GGSN:
- case DLT_JUNIPER_ES:
- case DLT_JUNIPER_MONITOR:
- case DLT_JUNIPER_SERVICES:
- case DLT_JUNIPER_ETHER:
- case DLT_JUNIPER_PPP:
- case DLT_JUNIPER_FRELAY:
- case DLT_JUNIPER_CHDLC:
- case DLT_JUNIPER_VP:
- /* juniper flags (including direction) are stored
- * the byte after the 3-byte magic number */
- if (dir) {
- /* match outgoing packets */
- b0 = gen_mcmp(OR_LINK, 3, BPF_B, 0, 0x01);
- } else {
- /* match incoming packets */
- b0 = gen_mcmp(OR_LINK, 3, BPF_B, 1, 0x01);
- }
- break;
-
- default:
- bpf_error("inbound/outbound not supported on linktype %d",
- linktype);
- b0 = NULL;
- /* NOTREACHED */
- }
- return (b0);
-}
-
-/* PF firewall log matched interface */
-struct block *
-gen_pf_ifname(const char *ifname)
-{
- struct block *b0;
- u_int len, off;
-
- if (linktype == DLT_PFLOG) {
- len = sizeof(((struct pfloghdr *)0)->ifname);
- off = offsetof(struct pfloghdr, ifname);
- } else {
- bpf_error("ifname not supported on linktype 0x%x", linktype);
- /* NOTREACHED */
- }
- if (strlen(ifname) >= len) {
- bpf_error("ifname interface names can only be %d characters",
- len-1);
- /* NOTREACHED */
- }
- b0 = gen_bcmp(OR_LINK, off, strlen(ifname), (const u_char *)ifname);
- return (b0);
-}
-
-/* PF firewall log ruleset name */
-struct block *
-gen_pf_ruleset(char *ruleset)
-{
- struct block *b0;
-
- if (linktype != DLT_PFLOG) {
- bpf_error("ruleset not supported on linktype 0x%x", linktype);
- /* NOTREACHED */
- }
- if (strlen(ruleset) >= sizeof(((struct pfloghdr *)0)->ruleset)) {
- bpf_error("ruleset names can only be %ld characters",
- (long)(sizeof(((struct pfloghdr *)0)->ruleset) - 1));
- /* NOTREACHED */
- }
- b0 = gen_bcmp(OR_LINK, offsetof(struct pfloghdr, ruleset),
- strlen(ruleset), (const u_char *)ruleset);
- return (b0);
-}
-
-/* PF firewall log rule number */
-struct block *
-gen_pf_rnr(int rnr)
-{
- struct block *b0;
-
- if (linktype == DLT_PFLOG) {
- b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, rulenr), BPF_W,
- (bpf_int32)rnr);
- } else {
- bpf_error("rnr not supported on linktype 0x%x", linktype);
- /* NOTREACHED */
- }
-
- return (b0);
-}
-
-/* PF firewall log sub-rule number */
-struct block *
-gen_pf_srnr(int srnr)
-{
- struct block *b0;
-
- if (linktype != DLT_PFLOG) {
- bpf_error("srnr not supported on linktype 0x%x", linktype);
- /* NOTREACHED */
- }
-
- b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, subrulenr), BPF_W,
- (bpf_int32)srnr);
- return (b0);
-}
-
-/* PF firewall log reason code */
-struct block *
-gen_pf_reason(int reason)
-{
- struct block *b0;
-
- if (linktype == DLT_PFLOG) {
- b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, reason), BPF_B,
- (bpf_int32)reason);
- } else {
- bpf_error("reason not supported on linktype 0x%x", linktype);
- /* NOTREACHED */
- }
-
- return (b0);
-}
-
-/* PF firewall log action */
-struct block *
-gen_pf_action(int action)
-{
- struct block *b0;
-
- if (linktype == DLT_PFLOG) {
- b0 = gen_cmp(OR_LINK, offsetof(struct pfloghdr, action), BPF_B,
- (bpf_int32)action);
- } else {
- bpf_error("action not supported on linktype 0x%x", linktype);
- /* NOTREACHED */
- }
-
- return (b0);
-}
-
-struct block *
-gen_acode(eaddr, q)
- register const u_char *eaddr;
- struct qual q;
-{
- if ((q.addr == Q_HOST || q.addr == Q_DEFAULT) && q.proto == Q_LINK) {
- if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX)
- return gen_ahostop(eaddr, (int)q.dir);
- }
- bpf_error("ARCnet address used in non-arc expression");
- /* NOTREACHED */
- return NULL;
-}
-
-static struct block *
-gen_ahostop(eaddr, dir)
- register const u_char *eaddr;
- register int dir;
-{
- register struct block *b0, *b1;
-
- switch (dir) {
- /* src comes first, different from Ethernet */
- case Q_SRC:
- return gen_bcmp(OR_LINK, 0, 1, eaddr);
-
- case Q_DST:
- return gen_bcmp(OR_LINK, 1, 1, eaddr);
-
- case Q_AND:
- b0 = gen_ahostop(eaddr, Q_SRC);
- b1 = gen_ahostop(eaddr, Q_DST);
- gen_and(b0, b1);
- return b1;
-
- case Q_DEFAULT:
- case Q_OR:
- b0 = gen_ahostop(eaddr, Q_SRC);
- b1 = gen_ahostop(eaddr, Q_DST);
- gen_or(b0, b1);
- return b1;
- }
- abort();
- /* NOTREACHED */
-}
-
-/*
- * support IEEE 802.1Q VLAN trunk over ethernet
- */
-struct block *
-gen_vlan(vlan_num)
- int vlan_num;
-{
- struct block *b0, *b1;
-
- /* can't check for VLAN-encapsulated packets inside MPLS */
- if (label_stack_depth > 0)
- bpf_error("no VLAN match after MPLS");
-
- /*
- * Change the offsets to point to the type and data fields within
- * the VLAN packet. Just increment the offsets, so that we
- * can support a hierarchy, e.g. "vlan 300 && vlan 200" to
- * capture VLAN 200 encapsulated within VLAN 100.
- *
- * XXX - this is a bit of a kludge. If we were to split the
- * compiler into a parser that parses an expression and
- * generates an expression tree, and a code generator that
- * takes an expression tree (which could come from our
- * parser or from some other parser) and generates BPF code,
- * we could perhaps make the offsets parameters of routines
- * and, in the handler for an "AND" node, pass to subnodes
- * other than the VLAN node the adjusted offsets.
- *
- * This would mean that "vlan" would, instead of changing the
- * behavior of *all* tests after it, change only the behavior
- * of tests ANDed with it. That would change the documented
- * semantics of "vlan", which might break some expressions.
- * However, it would mean that "(vlan and ip) or ip" would check
- * both for VLAN-encapsulated IP and IP-over-Ethernet, rather than
- * checking only for VLAN-encapsulated IP, so that could still
- * be considered worth doing; it wouldn't break expressions
- * that are of the form "vlan and ..." or "vlan N and ...",
- * which I suspect are the most common expressions involving
- * "vlan". "vlan or ..." doesn't necessarily do what the user
- * would really want, now, as all the "or ..." tests would
- * be done assuming a VLAN, even though the "or" could be viewed
- * as meaning "or, if this isn't a VLAN packet...".
- */
- orig_linktype = off_linktype; /* save original values */
- orig_nl = off_nl;
-
- switch (linktype) {
-
- case DLT_EN10MB:
- off_linktype += 4;
- off_nl_nosnap += 4;
- off_nl += 4;
- break;
-
- default:
- bpf_error("no VLAN support for data link type %d",
- linktype);
- /*NOTREACHED*/
- }
-
- /* check for VLAN */
- b0 = gen_cmp(OR_LINK, orig_linktype, BPF_H, (bpf_int32)ETHERTYPE_8021Q);
-
- /* If a specific VLAN is requested, check VLAN id */
- if (vlan_num >= 0) {
- b1 = gen_mcmp(OR_LINK, orig_nl, BPF_H, (bpf_int32)vlan_num,
- 0x0fff);
- gen_and(b0, b1);
- b0 = b1;
- }
-
- return (b0);
-}
-
-/*
- * support for MPLS
- */
-struct block *
-gen_mpls(label_num)
- int label_num;
-{
- struct block *b0,*b1;
-
- /*
- * Change the offsets to point to the type and data fields within
- * the MPLS packet. Just increment the offsets, so that we
- * can support a hierarchy, e.g. "mpls 100000 && mpls 1024" to
- * capture packets with an outer label of 100000 and an inner
- * label of 1024.
- *
- * XXX - this is a bit of a kludge. See comments in gen_vlan().
- */
- orig_nl = off_nl;
-
- if (label_stack_depth > 0) {
- /* just match the bottom-of-stack bit clear */
- b0 = gen_mcmp(OR_LINK, orig_nl-2, BPF_B, 0, 0x01);
- } else {
- /*
- * Indicate that we're checking MPLS-encapsulated headers,
- * to make sure higher level code generators don't try to
- * match against IP-related protocols such as Q_ARP, Q_RARP
- * etc.
- */
- switch (linktype) {
-
- case DLT_C_HDLC: /* fall through */
- case DLT_EN10MB:
- b0 = gen_linktype(ETHERTYPE_MPLS);
- break;
-
- case DLT_PPP:
- b0 = gen_linktype(PPP_MPLS_UCAST);
- break;
-
- /* FIXME add other DLT_s ...
- * for Frame-Relay/and ATM this may get messy due to SNAP headers
- * leave it for now */
-
- default:
- bpf_error("no MPLS support for data link type %d",
- linktype);
- b0 = NULL;
- /*NOTREACHED*/
- break;
- }
- }
-
- /* If a specific MPLS label is requested, check it */
- if (label_num >= 0) {
- label_num = label_num << 12; /* label is shifted 12 bits on the wire */
- b1 = gen_mcmp(OR_LINK, orig_nl, BPF_W, (bpf_int32)label_num,
- 0xfffff000); /* only compare the first 20 bits */
- gen_and(b0, b1);
- b0 = b1;
- }
-
- off_nl_nosnap += 4;
- off_nl += 4;
- label_stack_depth++;
- return (b0);
-}
-
-/*
- * Support PPPOE discovery and session.
- */
-struct block *
-gen_pppoed()
-{
- /* check for PPPoE discovery */
- return gen_linktype((bpf_int32)ETHERTYPE_PPPOED);
-}
-
-struct block *
-gen_pppoes()
-{
- struct block *b0;
-
- /*
- * Test against the PPPoE session link-layer type.
- */
- b0 = gen_linktype((bpf_int32)ETHERTYPE_PPPOES);
-
- /*
- * Change the offsets to point to the type and data fields within
- * the PPP packet.
- *
- * XXX - this is a bit of a kludge. If we were to split the
- * compiler into a parser that parses an expression and
- * generates an expression tree, and a code generator that
- * takes an expression tree (which could come from our
- * parser or from some other parser) and generates BPF code,
- * we could perhaps make the offsets parameters of routines
- * and, in the handler for an "AND" node, pass to subnodes
- * other than the PPPoE node the adjusted offsets.
- *
- * This would mean that "pppoes" would, instead of changing the
- * behavior of *all* tests after it, change only the behavior
- * of tests ANDed with it. That would change the documented
- * semantics of "pppoes", which might break some expressions.
- * However, it would mean that "(pppoes and ip) or ip" would check
- * both for VLAN-encapsulated IP and IP-over-Ethernet, rather than
- * checking only for VLAN-encapsulated IP, so that could still
- * be considered worth doing; it wouldn't break expressions
- * that are of the form "pppoes and ..." which I suspect are the
- * most common expressions involving "pppoes". "pppoes or ..."
- * doesn't necessarily do what the user would really want, now,
- * as all the "or ..." tests would be done assuming PPPoE, even
- * though the "or" could be viewed as meaning "or, if this isn't
- * a PPPoE packet...".
- */
- orig_linktype = off_linktype; /* save original values */
- orig_nl = off_nl;
-
- /*
- * The "network-layer" protocol is PPPoE, which has a 6-byte
- * PPPoE header, followed by PPP payload, so we set the
- * offsets to the network layer offset plus 6 bytes for
- * the PPPoE header plus the values appropriate for PPP when
- * encapsulated in Ethernet (which means there's no HDLC
- * encapsulation).
- */
- off_linktype = orig_nl + 6;
- off_nl = orig_nl + 6 + 2;
- off_nl_nosnap = orig_nl + 6 + 2;
-
- /*
- * Set the link-layer type to PPP, as all subsequent tests will
- * be on the encapsulated PPP header.
- */
- linktype = DLT_PPP;
-
- return b0;
-}
-
-struct block *
-gen_atmfield_code(atmfield, jvalue, jtype, reverse)
- int atmfield;
- bpf_int32 jvalue;
- bpf_u_int32 jtype;
- int reverse;
-{
- struct block *b0;
-
- switch (atmfield) {
-
- case A_VPI:
- if (!is_atm)
- bpf_error("'vpi' supported only on raw ATM");
- if (off_vpi == (u_int)-1)
- abort();
- b0 = gen_ncmp(OR_LINK, off_vpi, BPF_B, 0xffffffff, jtype,
- reverse, jvalue);
- break;
-
- case A_VCI:
- if (!is_atm)
- bpf_error("'vci' supported only on raw ATM");
- if (off_vci == (u_int)-1)
- abort();
- b0 = gen_ncmp(OR_LINK, off_vci, BPF_H, 0xffffffff, jtype,
- reverse, jvalue);
- break;
-
- case A_PROTOTYPE:
- if (off_proto == (u_int)-1)
- abort(); /* XXX - this isn't on FreeBSD */
- b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0x0f, jtype,
- reverse, jvalue);
- break;
-
- case A_MSGTYPE:
- if (off_payload == (u_int)-1)
- abort();
- b0 = gen_ncmp(OR_LINK, off_payload + MSG_TYPE_POS, BPF_B,
- 0xffffffff, jtype, reverse, jvalue);
- break;
-
- case A_CALLREFTYPE:
- if (!is_atm)
- bpf_error("'callref' supported only on raw ATM");
- if (off_proto == (u_int)-1)
- abort();
- b0 = gen_ncmp(OR_LINK, off_proto, BPF_B, 0xffffffff,
- jtype, reverse, jvalue);
- break;
-
- default:
- abort();
- }
- return b0;
-}
-
-struct block *
-gen_atmtype_abbrev(type)
- int type;
-{
- struct block *b0, *b1;
-
- switch (type) {
-
- case A_METAC:
- /* Get all packets in Meta signalling Circuit */
- if (!is_atm)
- bpf_error("'metac' supported only on raw ATM");
- b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
- b1 = gen_atmfield_code(A_VCI, 1, BPF_JEQ, 0);
- gen_and(b0, b1);
- break;
-
- case A_BCC:
- /* Get all packets in Broadcast Circuit*/
- if (!is_atm)
- bpf_error("'bcc' supported only on raw ATM");
- b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
- b1 = gen_atmfield_code(A_VCI, 2, BPF_JEQ, 0);
- gen_and(b0, b1);
- break;
-
- case A_OAMF4SC:
- /* Get all cells in Segment OAM F4 circuit*/
- if (!is_atm)
- bpf_error("'oam4sc' supported only on raw ATM");
- b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
- b1 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0);
- gen_and(b0, b1);
- break;
-
- case A_OAMF4EC:
- /* Get all cells in End-to-End OAM F4 Circuit*/
- if (!is_atm)
- bpf_error("'oam4ec' supported only on raw ATM");
- b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
- b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0);
- gen_and(b0, b1);
- break;
-
- case A_SC:
- /* Get all packets in connection Signalling Circuit */
- if (!is_atm)
- bpf_error("'sc' supported only on raw ATM");
- b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
- b1 = gen_atmfield_code(A_VCI, 5, BPF_JEQ, 0);
- gen_and(b0, b1);
- break;
-
- case A_ILMIC:
- /* Get all packets in ILMI Circuit */
- if (!is_atm)
- bpf_error("'ilmic' supported only on raw ATM");
- b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
- b1 = gen_atmfield_code(A_VCI, 16, BPF_JEQ, 0);
- gen_and(b0, b1);
- break;
-
- case A_LANE:
- /* Get all LANE packets */
- if (!is_atm)
- bpf_error("'lane' supported only on raw ATM");
- b1 = gen_atmfield_code(A_PROTOTYPE, PT_LANE, BPF_JEQ, 0);
-
- /*
- * Arrange that all subsequent tests assume LANE
- * rather than LLC-encapsulated packets, and set
- * the offsets appropriately for LANE-encapsulated
- * Ethernet.
- *
- * "off_mac" is the offset of the Ethernet header,
- * which is 2 bytes past the ATM pseudo-header
- * (skipping the pseudo-header and 2-byte LE Client
- * field). The other offsets are Ethernet offsets
- * relative to "off_mac".
- */
- is_lane = 1;
- off_mac = off_payload + 2; /* MAC header */
- off_linktype = off_mac + 12;
- off_nl = off_mac + 14; /* Ethernet II */
- off_nl_nosnap = off_mac + 17; /* 802.3+802.2 */
- break;
-
- case A_LLC:
- /* Get all LLC-encapsulated packets */
- if (!is_atm)
- bpf_error("'llc' supported only on raw ATM");
- b1 = gen_atmfield_code(A_PROTOTYPE, PT_LLC, BPF_JEQ, 0);
- is_lane = 0;
- break;
-
- default:
- abort();
- }
- return b1;
-}
-
-/*
- * Filtering for MTP2 messages based on li value
- * FISU, length is null
- * LSSU, length is 1 or 2
- * MSU, length is 3 or more
- */
-struct block *
-gen_mtp2type_abbrev(type)
- int type;
-{
- struct block *b0, *b1;
-
- switch (type) {
-
- case M_FISU:
- if ( (linktype != DLT_MTP2) &&
- (linktype != DLT_MTP2_WITH_PHDR) )
- bpf_error("'fisu' supported only on MTP2");
- /* gen_ncmp(offrel, offset, size, mask, jtype, reverse, value) */
- b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JEQ, 0, 0);
- break;
-
- case M_LSSU:
- if ( (linktype != DLT_MTP2) &&
- (linktype != DLT_MTP2_WITH_PHDR) )
- bpf_error("'lssu' supported only on MTP2");
- b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 1, 2);
- b1 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 0, 0);
- gen_and(b1, b0);
- break;
-
- case M_MSU:
- if ( (linktype != DLT_MTP2) &&
- (linktype != DLT_MTP2_WITH_PHDR) )
- bpf_error("'msu' supported only on MTP2");
- b0 = gen_ncmp(OR_PACKET, off_li, BPF_B, 0x3f, BPF_JGT, 0, 2);
- break;
-
- default:
- abort();
- }
- return b0;
-}
-
-struct block *
-gen_mtp3field_code(mtp3field, jvalue, jtype, reverse)
- int mtp3field;
- bpf_u_int32 jvalue;
- bpf_u_int32 jtype;
- int reverse;
-{
- struct block *b0;
- bpf_u_int32 val1 , val2 , val3;
-
- switch (mtp3field) {
-
- case M_SIO:
- if (off_sio == (u_int)-1)
- bpf_error("'sio' supported only on SS7");
- /* sio coded on 1 byte so max value 255 */
- if(jvalue > 255)
- bpf_error("sio value %u too big; max value = 255",
- jvalue);
- b0 = gen_ncmp(OR_PACKET, off_sio, BPF_B, 0xffffffff,
- (u_int)jtype, reverse, (u_int)jvalue);
- break;
-
- case M_OPC:
- if (off_opc == (u_int)-1)
- bpf_error("'opc' supported only on SS7");
- /* opc coded on 14 bits so max value 16383 */
- if (jvalue > 16383)
- bpf_error("opc value %u too big; max value = 16383",
- jvalue);
- /* the following instructions are made to convert jvalue
- * to the form used to write opc in an ss7 message*/
- val1 = jvalue & 0x00003c00;
- val1 = val1 >>10;
- val2 = jvalue & 0x000003fc;
- val2 = val2 <<6;
- val3 = jvalue & 0x00000003;
- val3 = val3 <<22;
- jvalue = val1 + val2 + val3;
- b0 = gen_ncmp(OR_PACKET, off_opc, BPF_W, 0x00c0ff0f,
- (u_int)jtype, reverse, (u_int)jvalue);
- break;
-
- case M_DPC:
- if (off_dpc == (u_int)-1)
- bpf_error("'dpc' supported only on SS7");
- /* dpc coded on 14 bits so max value 16383 */
- if (jvalue > 16383)
- bpf_error("dpc value %u too big; max value = 16383",
- jvalue);
- /* the following instructions are made to convert jvalue
- * to the forme used to write dpc in an ss7 message*/
- val1 = jvalue & 0x000000ff;
- val1 = val1 << 24;
- val2 = jvalue & 0x00003f00;
- val2 = val2 << 8;
- jvalue = val1 + val2;
- b0 = gen_ncmp(OR_PACKET, off_dpc, BPF_W, 0xff3f0000,
- (u_int)jtype, reverse, (u_int)jvalue);
- break;
-
- case M_SLS:
- if (off_sls == (u_int)-1)
- bpf_error("'sls' supported only on SS7");
- /* sls coded on 4 bits so max value 15 */
- if (jvalue > 15)
- bpf_error("sls value %u too big; max value = 15",
- jvalue);
- /* the following instruction is made to convert jvalue
- * to the forme used to write sls in an ss7 message*/
- jvalue = jvalue << 4;
- b0 = gen_ncmp(OR_PACKET, off_sls, BPF_B, 0xf0,
- (u_int)jtype,reverse, (u_int)jvalue);
- break;
-
- default:
- abort();
- }
- return b0;
-}
-
-static struct block *
-gen_msg_abbrev(type)
- int type;
-{
- struct block *b1;
-
- /*
- * Q.2931 signalling protocol messages for handling virtual circuits
- * establishment and teardown
- */
- switch (type) {
-
- case A_SETUP:
- b1 = gen_atmfield_code(A_MSGTYPE, SETUP, BPF_JEQ, 0);
- break;
-
- case A_CALLPROCEED:
- b1 = gen_atmfield_code(A_MSGTYPE, CALL_PROCEED, BPF_JEQ, 0);
- break;
-
- case A_CONNECT:
- b1 = gen_atmfield_code(A_MSGTYPE, CONNECT, BPF_JEQ, 0);
- break;
-
- case A_CONNECTACK:
- b1 = gen_atmfield_code(A_MSGTYPE, CONNECT_ACK, BPF_JEQ, 0);
- break;
-
- case A_RELEASE:
- b1 = gen_atmfield_code(A_MSGTYPE, RELEASE, BPF_JEQ, 0);
- break;
-
- case A_RELEASE_DONE:
- b1 = gen_atmfield_code(A_MSGTYPE, RELEASE_DONE, BPF_JEQ, 0);
- break;
-
- default:
- abort();
- }
- return b1;
-}
-
-struct block *
-gen_atmmulti_abbrev(type)
- int type;
-{
- struct block *b0, *b1;
-
- switch (type) {
-
- case A_OAM:
- if (!is_atm)
- bpf_error("'oam' supported only on raw ATM");
- b1 = gen_atmmulti_abbrev(A_OAMF4);
- break;
-
- case A_OAMF4:
- if (!is_atm)
- bpf_error("'oamf4' supported only on raw ATM");
- /* OAM F4 type */
- b0 = gen_atmfield_code(A_VCI, 3, BPF_JEQ, 0);
- b1 = gen_atmfield_code(A_VCI, 4, BPF_JEQ, 0);
- gen_or(b0, b1);
- b0 = gen_atmfield_code(A_VPI, 0, BPF_JEQ, 0);
- gen_and(b0, b1);
- break;
-
- case A_CONNECTMSG:
- /*
- * Get Q.2931 signalling messages for switched
- * virtual connection
- */
- if (!is_atm)
- bpf_error("'connectmsg' supported only on raw ATM");
- b0 = gen_msg_abbrev(A_SETUP);
- b1 = gen_msg_abbrev(A_CALLPROCEED);
- gen_or(b0, b1);
- b0 = gen_msg_abbrev(A_CONNECT);
- gen_or(b0, b1);
- b0 = gen_msg_abbrev(A_CONNECTACK);
- gen_or(b0, b1);
- b0 = gen_msg_abbrev(A_RELEASE);
- gen_or(b0, b1);
- b0 = gen_msg_abbrev(A_RELEASE_DONE);
- gen_or(b0, b1);
- b0 = gen_atmtype_abbrev(A_SC);
- gen_and(b0, b1);
- break;
-
- case A_METACONNECT:
- if (!is_atm)
- bpf_error("'metaconnect' supported only on raw ATM");
- b0 = gen_msg_abbrev(A_SETUP);
- b1 = gen_msg_abbrev(A_CALLPROCEED);
- gen_or(b0, b1);
- b0 = gen_msg_abbrev(A_CONNECT);
- gen_or(b0, b1);
- b0 = gen_msg_abbrev(A_RELEASE);
- gen_or(b0, b1);
- b0 = gen_msg_abbrev(A_RELEASE_DONE);
- gen_or(b0, b1);
- b0 = gen_atmtype_abbrev(A_METAC);
- gen_and(b0, b1);
- break;
-
- default:
- abort();
- }
- return b1;
-}