6818 lines
154 KiB
C
6818 lines
154 KiB
C
/*#define CHASE_CHAIN*/
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/*
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* Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that: (1) source code distributions
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* retain the above copyright notice and this paragraph in its entirety, (2)
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* distributions including binary code include the above copyright notice and
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* this paragraph in its entirety in the documentation or other materials
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* provided with the distribution, and (3) all advertising materials mentioning
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* features or use of this software display the following acknowledgement:
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* ``This product includes software developed by the University of California,
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* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
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* the University nor the names of its contributors may be used to endorse
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* or promote products derived from this software without specific prior
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* written permission.
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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*
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* $FreeBSD$
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*/
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#ifndef lint
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static const char rcsid[] _U_ =
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"@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.221.2.34 2005/09/05 09:08:04 guy Exp $ (LBL)";
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#endif
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#ifdef WIN32
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#include <pcap-stdinc.h>
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#else /* WIN32 */
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#include <sys/types.h>
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#include <sys/socket.h>
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#endif /* WIN32 */
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/*
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* XXX - why was this included even on UNIX?
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*/
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#ifdef __MINGW32__
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#include "IP6_misc.h"
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#endif
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#ifndef WIN32
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#ifdef __NetBSD__
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#include <sys/param.h>
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#endif
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#include <netinet/in.h>
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#endif /* WIN32 */
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#include <stdlib.h>
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#include <string.h>
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#include <memory.h>
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#include <setjmp.h>
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#include <stdarg.h>
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#ifdef MSDOS
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#include "pcap-dos.h"
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#endif
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#include "pcap-int.h"
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#include "ethertype.h"
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#include "nlpid.h"
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#include "llc.h"
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#include "gencode.h"
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#include "atmuni31.h"
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#include "sunatmpos.h"
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#include "ppp.h"
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#include "sll.h"
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#include "arcnet.h"
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#include "pf.h"
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#ifndef offsetof
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#define offsetof(s, e) ((size_t)&((s *)0)->e)
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#endif
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#ifdef INET6
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#ifndef WIN32
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#include <netdb.h> /* for "struct addrinfo" */
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#endif /* WIN32 */
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#endif /*INET6*/
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#include <pcap-namedb.h>
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#define ETHERMTU 1500
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#ifndef IPPROTO_SCTP
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#define IPPROTO_SCTP 132
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#endif
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#ifdef HAVE_OS_PROTO_H
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#include "os-proto.h"
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#endif
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#define JMP(c) ((c)|BPF_JMP|BPF_K)
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/* Locals */
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static jmp_buf top_ctx;
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static pcap_t *bpf_pcap;
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/* Hack for updating VLAN, MPLS, and PPPoE offsets. */
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static u_int orig_linktype = -1U, orig_nl = -1U, label_stack_depth = -1U;
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/* XXX */
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#ifdef PCAP_FDDIPAD
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static int pcap_fddipad;
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#endif
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/* VARARGS */
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void
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bpf_error(const char *fmt, ...)
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{
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va_list ap;
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va_start(ap, fmt);
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if (bpf_pcap != NULL)
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(void)vsnprintf(pcap_geterr(bpf_pcap), PCAP_ERRBUF_SIZE,
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fmt, ap);
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va_end(ap);
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longjmp(top_ctx, 1);
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/* NOTREACHED */
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}
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static void init_linktype(pcap_t *);
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static int alloc_reg(void);
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static void free_reg(int);
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static struct block *root;
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/*
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* Value passed to gen_load_a() to indicate what the offset argument
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* is relative to.
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*/
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enum e_offrel {
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OR_PACKET, /* relative to the beginning of the packet */
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OR_LINK, /* relative to the link-layer header */
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OR_NET, /* relative to the network-layer header */
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OR_NET_NOSNAP, /* relative to the network-layer header, with no SNAP header at the link layer */
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OR_TRAN_IPV4, /* relative to the transport-layer header, with IPv4 network layer */
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OR_TRAN_IPV6 /* relative to the transport-layer header, with IPv6 network layer */
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};
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/*
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* We divy out chunks of memory rather than call malloc each time so
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* we don't have to worry about leaking memory. It's probably
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* not a big deal if all this memory was wasted but if this ever
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* goes into a library that would probably not be a good idea.
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*
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* XXX - this *is* in a library....
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*/
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#define NCHUNKS 16
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#define CHUNK0SIZE 1024
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struct chunk {
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u_int n_left;
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void *m;
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};
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static struct chunk chunks[NCHUNKS];
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static int cur_chunk;
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static void *newchunk(u_int);
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static void freechunks(void);
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static inline struct block *new_block(int);
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static inline struct slist *new_stmt(int);
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static struct block *gen_retblk(int);
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static inline void syntax(void);
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static void backpatch(struct block *, struct block *);
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static void merge(struct block *, struct block *);
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static struct block *gen_cmp(enum e_offrel, u_int, u_int, bpf_int32);
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static struct block *gen_cmp_gt(enum e_offrel, u_int, u_int, bpf_int32);
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static struct block *gen_cmp_ge(enum e_offrel, u_int, u_int, bpf_int32);
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static struct block *gen_cmp_lt(enum e_offrel, u_int, u_int, bpf_int32);
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static struct block *gen_cmp_le(enum e_offrel, u_int, u_int, bpf_int32);
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static struct block *gen_mcmp(enum e_offrel, u_int, u_int, bpf_int32,
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bpf_u_int32);
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static struct block *gen_bcmp(enum e_offrel, u_int, u_int, const u_char *);
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static struct block *gen_ncmp(enum e_offrel, bpf_u_int32, bpf_u_int32,
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bpf_u_int32, bpf_u_int32, int, bpf_int32);
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static struct slist *gen_load_llrel(u_int, u_int);
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static struct slist *gen_load_a(enum e_offrel, u_int, u_int);
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static struct slist *gen_loadx_iphdrlen(void);
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static struct block *gen_uncond(int);
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static inline struct block *gen_true(void);
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static inline struct block *gen_false(void);
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static struct block *gen_ether_linktype(int);
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static struct block *gen_linux_sll_linktype(int);
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static void insert_radiotap_load_llprefixlen(struct block *);
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static void insert_load_llprefixlen(struct block *);
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static struct slist *gen_llprefixlen(void);
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static struct block *gen_linktype(int);
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static struct block *gen_snap(bpf_u_int32, bpf_u_int32, u_int);
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static struct block *gen_llc_linktype(int);
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static struct block *gen_hostop(bpf_u_int32, bpf_u_int32, int, int, u_int, u_int);
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#ifdef INET6
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static struct block *gen_hostop6(struct in6_addr *, struct in6_addr *, int, int, u_int, u_int);
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#endif
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static struct block *gen_ahostop(const u_char *, int);
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static struct block *gen_ehostop(const u_char *, int);
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static struct block *gen_fhostop(const u_char *, int);
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static struct block *gen_thostop(const u_char *, int);
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static struct block *gen_wlanhostop(const u_char *, int);
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static struct block *gen_ipfchostop(const u_char *, int);
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static struct block *gen_dnhostop(bpf_u_int32, int);
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static struct block *gen_mpls_linktype(int);
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static struct block *gen_host(bpf_u_int32, bpf_u_int32, int, int);
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#ifdef INET6
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static struct block *gen_host6(struct in6_addr *, struct in6_addr *, int, int);
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#endif
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#ifndef INET6
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static struct block *gen_gateway(const u_char *, bpf_u_int32 **, int, int);
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#endif
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static struct block *gen_ipfrag(void);
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static struct block *gen_portatom(int, bpf_int32);
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static struct block *gen_portrangeatom(int, bpf_int32, bpf_int32);
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#ifdef INET6
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static struct block *gen_portatom6(int, bpf_int32);
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static struct block *gen_portrangeatom6(int, bpf_int32, bpf_int32);
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#endif
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struct block *gen_portop(int, int, int);
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static struct block *gen_port(int, int, int);
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struct block *gen_portrangeop(int, int, int, int);
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static struct block *gen_portrange(int, int, int, int);
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#ifdef INET6
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struct block *gen_portop6(int, int, int);
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static struct block *gen_port6(int, int, int);
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struct block *gen_portrangeop6(int, int, int, int);
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static struct block *gen_portrange6(int, int, int, int);
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#endif
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static int lookup_proto(const char *, int);
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static struct block *gen_protochain(int, int, int);
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static struct block *gen_proto(int, int, int);
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static struct slist *xfer_to_x(struct arth *);
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static struct slist *xfer_to_a(struct arth *);
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static struct block *gen_mac_multicast(int);
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static struct block *gen_len(int, int);
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static struct block *gen_msg_abbrev(int type);
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static void *
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newchunk(n)
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u_int n;
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{
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struct chunk *cp;
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int k;
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size_t size;
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#ifndef __NetBSD__
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/* XXX Round up to nearest long. */
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n = (n + sizeof(long) - 1) & ~(sizeof(long) - 1);
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#else
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/* XXX Round up to structure boundary. */
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n = ALIGN(n);
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#endif
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cp = &chunks[cur_chunk];
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if (n > cp->n_left) {
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++cp, k = ++cur_chunk;
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if (k >= NCHUNKS)
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bpf_error("out of memory");
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size = CHUNK0SIZE << k;
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cp->m = (void *)malloc(size);
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if (cp->m == NULL)
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bpf_error("out of memory");
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memset((char *)cp->m, 0, size);
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cp->n_left = size;
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if (n > size)
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bpf_error("out of memory");
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}
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cp->n_left -= n;
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return (void *)((char *)cp->m + cp->n_left);
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}
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static void
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freechunks()
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{
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int i;
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cur_chunk = 0;
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for (i = 0; i < NCHUNKS; ++i)
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if (chunks[i].m != NULL) {
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free(chunks[i].m);
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chunks[i].m = NULL;
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}
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}
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/*
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* A strdup whose allocations are freed after code generation is over.
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*/
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char *
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sdup(s)
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register const char *s;
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{
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int n = strlen(s) + 1;
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char *cp = newchunk(n);
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strlcpy(cp, s, n);
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return (cp);
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}
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static inline struct block *
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new_block(code)
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int code;
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{
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struct block *p;
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p = (struct block *)newchunk(sizeof(*p));
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p->s.code = code;
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p->head = p;
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return p;
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}
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static inline struct slist *
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new_stmt(code)
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int code;
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{
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struct slist *p;
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p = (struct slist *)newchunk(sizeof(*p));
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p->s.code = code;
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return p;
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}
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static struct block *
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gen_retblk(v)
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int v;
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{
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struct block *b = new_block(BPF_RET|BPF_K);
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b->s.k = v;
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return b;
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}
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static inline void
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syntax()
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{
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bpf_error("syntax error in filter expression");
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}
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static bpf_u_int32 netmask;
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static int snaplen;
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int no_optimize;
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int
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pcap_compile(pcap_t *p, struct bpf_program *program,
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char *buf, int optimize, bpf_u_int32 mask)
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{
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extern int n_errors;
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int len;
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no_optimize = 0;
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n_errors = 0;
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root = NULL;
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bpf_pcap = p;
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if (setjmp(top_ctx)) {
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lex_cleanup();
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freechunks();
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return (-1);
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}
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netmask = mask;
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snaplen = pcap_snapshot(p);
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if (snaplen == 0) {
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snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
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"snaplen of 0 rejects all packets");
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return -1;
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}
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lex_init(buf ? buf : "");
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init_linktype(p);
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(void)pcap_parse();
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if (n_errors)
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syntax();
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if (root == NULL)
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root = gen_retblk(snaplen);
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if (optimize && !no_optimize) {
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bpf_optimize(&root);
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if (root == NULL ||
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(root->s.code == (BPF_RET|BPF_K) && root->s.k == 0))
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bpf_error("expression rejects all packets");
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}
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program->bf_insns = icode_to_fcode(root, &len);
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program->bf_len = len;
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lex_cleanup();
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freechunks();
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return (0);
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}
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/*
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* entry point for using the compiler with no pcap open
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* pass in all the stuff that is needed explicitly instead.
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*/
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int
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pcap_compile_nopcap(int snaplen_arg, int linktype_arg,
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struct bpf_program *program,
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char *buf, int optimize, bpf_u_int32 mask)
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{
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pcap_t *p;
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int ret;
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p = pcap_open_dead(linktype_arg, snaplen_arg);
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if (p == NULL)
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return (-1);
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ret = pcap_compile(p, program, buf, optimize, mask);
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pcap_close(p);
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return (ret);
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}
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/*
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* Clean up a "struct bpf_program" by freeing all the memory allocated
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* in it.
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*/
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void
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pcap_freecode(struct bpf_program *program)
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{
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program->bf_len = 0;
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if (program->bf_insns != NULL) {
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free((char *)program->bf_insns);
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program->bf_insns = NULL;
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}
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}
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/*
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* Backpatch the blocks in 'list' to 'target'. The 'sense' field indicates
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* which of the jt and jf fields has been resolved and which is a pointer
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* back to another unresolved block (or nil). At least one of the fields
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* in each block is already resolved.
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*/
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static void
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backpatch(list, target)
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struct block *list, *target;
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{
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struct block *next;
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while (list) {
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if (!list->sense) {
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next = JT(list);
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JT(list) = target;
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} else {
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next = JF(list);
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JF(list) = target;
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}
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list = next;
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}
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}
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/*
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* Merge the lists in b0 and b1, using the 'sense' field to indicate
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* which of jt and jf is the link.
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*/
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static void
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merge(b0, b1)
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struct block *b0, *b1;
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{
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register struct block **p = &b0;
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/* Find end of list. */
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while (*p)
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p = !((*p)->sense) ? &JT(*p) : &JF(*p);
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/* Concatenate the lists. */
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*p = b1;
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}
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void
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finish_parse(p)
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struct block *p;
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{
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backpatch(p, gen_retblk(snaplen));
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p->sense = !p->sense;
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backpatch(p, gen_retblk(0));
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root = p->head;
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/*
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* Insert before the statements of the first (root) block any
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* statements needed to load the lengths of any variable-length
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* headers into registers.
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*
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* XXX - a fancier strategy would be to insert those before the
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* statements of all blocks that use those lengths and that
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* have no predecessors that use them, so that we only compute
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* the lengths if we need them. There might be even better
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|
* approaches than that. However, as we're currently only
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* handling variable-length radiotap headers, and as all
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* filtering expressions other than raw link[M:N] tests
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* require the length of that header, doing more for that
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|
* header length isn't really worth the effort.
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*/
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insert_load_llprefixlen(root);
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}
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|
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void
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gen_and(b0, b1)
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struct block *b0, *b1;
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{
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backpatch(b0, b1->head);
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b0->sense = !b0->sense;
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b1->sense = !b1->sense;
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merge(b1, b0);
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b1->sense = !b1->sense;
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b1->head = b0->head;
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}
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void
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gen_or(b0, b1)
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struct block *b0, *b1;
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{
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|
b0->sense = !b0->sense;
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|
backpatch(b0, b1->head);
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|
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.
|
|
* It's usually 0, except for 802.11 with a fixed-length radio header.
|
|
*/
|
|
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.
|
|
*/
|
|
static u_int off_mac;
|
|
|
|
/*
|
|
* "off_linktype" is the offset to information in the link-layer header
|
|
* giving the packet type.
|
|
*
|
|
* 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 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.
|
|
*
|
|
* 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_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 = 144+24;
|
|
off_nl = 144+32; /* Prism+802.11+802.2+SNAP */
|
|
off_nl_nosnap = 144+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.
|
|
*/
|
|
off_ll = 64;
|
|
off_linktype = 64+24;
|
|
off_nl = 64+32; /* Radio+802.11+802.2+SNAP */
|
|
off_nl_nosnap = 64+27; /* Radio+802.11+802.2 */
|
|
return;
|
|
|
|
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;
|
|
|
|
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_MTP2:
|
|
off_sio = 3;
|
|
off_opc = 4;
|
|
off_dpc = 4;
|
|
off_sls = 7;
|
|
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;
|
|
}
|
|
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.
|
|
*/
|
|
if (s != NULL) {
|
|
s2 = new_stmt(BPF_LD|BPF_IND|size);
|
|
s2->s.k = offset;
|
|
sappend(s, s2);
|
|
} else {
|
|
s = new_stmt(BPF_LD|BPF_ABS|size);
|
|
s->s.k = offset;
|
|
}
|
|
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 = gen_load_llrel(offset, size);
|
|
break;
|
|
|
|
case OR_LINK:
|
|
s = gen_load_llrel(off_ll + 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,
|
|
* in bytes.
|
|
*/
|
|
s = gen_loadx_iphdrlen();
|
|
|
|
/*
|
|
* Load the item at {length of the link-layer header} +
|
|
* {length of the IPv4 header} + {specified offset}.
|
|
*/
|
|
s2 = new_stmt(BPF_LD|BPF_IND|size);
|
|
s2->s.k = 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; if there's a fixed-length
|
|
* header preceding it, its length is included in
|
|
* the off_ variables, so it doesn't need to be added.
|
|
*/
|
|
s = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
|
|
s->s.k = 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;
|
|
}
|
|
}
|
|
|
|
|
|
static void
|
|
insert_load_llprefixlen(b)
|
|
struct block *b;
|
|
{
|
|
switch (linktype) {
|
|
|
|
case DLT_IEEE802_11_RADIO:
|
|
insert_radiotap_load_llprefixlen(b);
|
|
}
|
|
}
|
|
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* 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_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_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 IP.
|
|
*
|
|
* 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:
|
|
#ifdef INET6
|
|
case ETHERTYPE_IPV6:
|
|
#endif
|
|
return gen_true(); /* always true */
|
|
|
|
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:
|
|
/* 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(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(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(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(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)
|
|
bpf_u_int32 addr;
|
|
bpf_u_int32 mask;
|
|
int proto;
|
|
int dir;
|
|
{
|
|
struct block *b0, *b1;
|
|
|
|
switch (proto) {
|
|
|
|
case Q_DEFAULT:
|
|
b0 = gen_host(addr, mask, Q_IP, dir);
|
|
/*
|
|
* 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);
|
|
gen_or(b0, b1);
|
|
b0 = gen_host(addr, mask, Q_RARP, dir);
|
|
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 host");
|
|
|
|
case Q_SCTP:
|
|
bpf_error("'sctp' modifier applied to host");
|
|
|
|
case Q_UDP:
|
|
bpf_error("'udp' modifier applied to host");
|
|
|
|
case Q_ICMP:
|
|
bpf_error("'icmp' modifier applied to host");
|
|
|
|
case Q_IGMP:
|
|
bpf_error("'igmp' modifier applied to host");
|
|
|
|
case Q_IGRP:
|
|
bpf_error("'igrp' modifier applied to host");
|
|
|
|
case Q_PIM:
|
|
bpf_error("'pim' modifier applied to host");
|
|
|
|
case Q_VRRP:
|
|
bpf_error("'vrrp' modifier applied to host");
|
|
|
|
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 host");
|
|
#endif /* INET6 */
|
|
|
|
case Q_AH:
|
|
bpf_error("'ah' modifier applied to host");
|
|
|
|
case Q_ESP:
|
|
bpf_error("'esp' modifier applied to host");
|
|
|
|
case Q_ISO:
|
|
bpf_error("ISO host filtering not implemented");
|
|
|
|
case Q_ESIS:
|
|
bpf_error("'esis' modifier applied to host");
|
|
|
|
case Q_ISIS:
|
|
bpf_error("'isis' modifier applied to host");
|
|
|
|
case Q_CLNP:
|
|
bpf_error("'clnp' modifier applied to host");
|
|
|
|
case Q_STP:
|
|
bpf_error("'stp' modifier applied to host");
|
|
|
|
case Q_IPX:
|
|
bpf_error("IPX host filtering not implemented");
|
|
|
|
case Q_NETBEUI:
|
|
bpf_error("'netbeui' modifier applied to host");
|
|
|
|
case Q_RADIO:
|
|
bpf_error("'radio' modifier applied to host");
|
|
|
|
default:
|
|
abort();
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
#ifdef INET6
|
|
static struct block *
|
|
gen_host6(addr, mask, proto, dir)
|
|
struct in6_addr *addr;
|
|
struct in6_addr *mask;
|
|
int proto;
|
|
int dir;
|
|
{
|
|
switch (proto) {
|
|
|
|
case Q_DEFAULT:
|
|
return gen_host6(addr, mask, Q_IPV6, dir);
|
|
|
|
case Q_IP:
|
|
bpf_error("'ip' modifier applied to ip6 host");
|
|
|
|
case Q_RARP:
|
|
bpf_error("'rarp' modifier applied to ip6 host");
|
|
|
|
case Q_ARP:
|
|
bpf_error("'arp' modifier applied to ip6 host");
|
|
|
|
case Q_SCTP:
|
|
bpf_error("'sctp' modifier applied to host");
|
|
|
|
case Q_TCP:
|
|
bpf_error("'tcp' modifier applied to host");
|
|
|
|
case Q_UDP:
|
|
bpf_error("'udp' modifier applied to host");
|
|
|
|
case Q_ICMP:
|
|
bpf_error("'icmp' modifier applied to host");
|
|
|
|
case Q_IGMP:
|
|
bpf_error("'igmp' modifier applied to host");
|
|
|
|
case Q_IGRP:
|
|
bpf_error("'igrp' modifier applied to host");
|
|
|
|
case Q_PIM:
|
|
bpf_error("'pim' modifier applied to host");
|
|
|
|
case Q_VRRP:
|
|
bpf_error("'vrrp' modifier applied to host");
|
|
|
|
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 host");
|
|
|
|
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 host");
|
|
|
|
case Q_AH:
|
|
bpf_error("'ah' modifier applied to host");
|
|
|
|
case Q_ESP:
|
|
bpf_error("'esp' modifier applied to host");
|
|
|
|
case Q_ISO:
|
|
bpf_error("ISO host filtering not implemented");
|
|
|
|
case Q_ESIS:
|
|
bpf_error("'esis' modifier applied to host");
|
|
|
|
case Q_ISIS:
|
|
bpf_error("'isis' modifier applied to host");
|
|
|
|
case Q_CLNP:
|
|
bpf_error("'clnp' modifier applied to host");
|
|
|
|
case Q_STP:
|
|
bpf_error("'stp' modifier applied to host");
|
|
|
|
case Q_IPX:
|
|
bpf_error("IPX host filtering not implemented");
|
|
|
|
case Q_NETBEUI:
|
|
bpf_error("'netbeui' modifier applied to host");
|
|
|
|
case Q_RADIO:
|
|
bpf_error("'radio' modifier applied to host");
|
|
|
|
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:
|
|
if (linktype == DLT_EN10MB)
|
|
b0 = gen_ehostop(eaddr, Q_OR);
|
|
else if (linktype == DLT_FDDI)
|
|
b0 = gen_fhostop(eaddr, Q_OR);
|
|
else if (linktype == DLT_IEEE802)
|
|
b0 = gen_thostop(eaddr, Q_OR);
|
|
else if (linktype == DLT_IEEE802_11 ||
|
|
linktype == DLT_IEEE802_11_RADIO_AVS ||
|
|
linktype == DLT_IEEE802_11_RADIO ||
|
|
linktype == DLT_PRISM_HEADER)
|
|
b0 = gen_wlanhostop(eaddr, Q_OR);
|
|
else if (linktype == DLT_SUNATM && 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);
|
|
} else if (linktype == DLT_IP_OVER_FC)
|
|
b0 = gen_ipfchostop(eaddr, Q_OR);
|
|
else
|
|
bpf_error(
|
|
"'gateway' supported only on ethernet/FDDI/token ring/802.11/Fibre Channel");
|
|
|
|
b1 = gen_host(**alist++, 0xffffffff, proto, Q_OR);
|
|
while (*alist) {
|
|
tmp = gen_host(**alist++, 0xffffffff, proto, Q_OR);
|
|
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");
|
|
|
|
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_nl + 9;
|
|
i++;
|
|
/* X = ip->ip_hl << 2 */
|
|
s[i] = new_stmt(BPF_LDX|BPF_MSH|BPF_B);
|
|
s[i]->s.k = 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_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_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_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_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_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 *sin;
|
|
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);
|
|
|
|
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:
|
|
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));
|
|
} 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);
|
|
while (*alist) {
|
|
tmp = gen_host(**alist++, 0xffffffff,
|
|
tproto, dir);
|
|
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;
|
|
|
|
sin = (struct sockaddr_in *)
|
|
res->ai_addr;
|
|
tmp = gen_host(ntohl(sin->sin_addr.s_addr),
|
|
0xffffffff, tproto, dir);
|
|
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);
|
|
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
|
|
{
|
|
struct block *b;
|
|
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
|
|
{
|
|
struct block *b;
|
|
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");
|
|
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);
|
|
|
|
default:
|
|
bpf_error("Mask syntax for networks only");
|
|
/* NOTREACHED */
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
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);
|
|
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);
|
|
}
|
|
|
|
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);
|
|
freeaddrinfo(res);
|
|
return b;
|
|
|
|
default:
|
|
bpf_error("invalid qualifier against IPv6 address");
|
|
/* NOTREACHED */
|
|
}
|
|
}
|
|
#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) {
|
|
if (linktype == DLT_EN10MB)
|
|
return gen_ehostop(eaddr, (int)q.dir);
|
|
if (linktype == DLT_FDDI)
|
|
return gen_fhostop(eaddr, (int)q.dir);
|
|
if (linktype == DLT_IEEE802)
|
|
return gen_thostop(eaddr, (int)q.dir);
|
|
if (linktype == DLT_IEEE802_11 ||
|
|
linktype == DLT_IEEE802_11_RADIO_AVS ||
|
|
linktype == DLT_IEEE802_11_RADIO ||
|
|
linktype == DLT_PRISM_HEADER)
|
|
return gen_wlanhostop(eaddr, (int)q.dir);
|
|
if (linktype == DLT_SUNATM && 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;
|
|
}
|
|
if (linktype == DLT_IP_OVER_FC)
|
|
return gen_ipfchostop(eaddr, (int)q.dir);
|
|
bpf_error("ethernet addresses supported only on ethernet/FDDI/token ring/802.11/ATM LANE/Fibre Channel");
|
|
}
|
|
bpf_error("ethernet address used in non-ether expression");
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
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, index, size)
|
|
int proto;
|
|
struct arth *index;
|
|
int size;
|
|
{
|
|
struct slist *s, *tmp;
|
|
struct block *b;
|
|
int regno = alloc_reg();
|
|
|
|
free_reg(index->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(index);
|
|
|
|
/*
|
|
* Load the item at that offset.
|
|
*/
|
|
tmp = new_stmt(BPF_LD|BPF_IND|size);
|
|
sappend(s, tmp);
|
|
sappend(index->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(index));
|
|
sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
|
|
sappend(s, new_stmt(BPF_MISC|BPF_TAX));
|
|
} else
|
|
s = xfer_to_x(index);
|
|
|
|
/*
|
|
* 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(index->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(index));
|
|
sappend(s, new_stmt(BPF_ALU|BPF_ADD|BPF_X));
|
|
sappend(s, new_stmt(BPF_MISC|BPF_TAX));
|
|
} else
|
|
s = xfer_to_x(index);
|
|
|
|
/*
|
|
* Load the item at the sum of the offset we've put in the
|
|
* X register and the offset of the start of the network
|
|
* layer header.
|
|
*/
|
|
tmp = new_stmt(BPF_LD|BPF_IND|size);
|
|
tmp->s.k = off_nl;
|
|
sappend(s, tmp);
|
|
sappend(index->s, s);
|
|
|
|
/*
|
|
* Do the computation only if the packet contains
|
|
* the protocol in question.
|
|
*/
|
|
b = gen_proto_abbrev(proto);
|
|
if (index->b)
|
|
gen_and(index->b, b);
|
|
index->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.
|
|
* 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 offset
|
|
* of the beginning of 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.
|
|
*/
|
|
sappend(s, xfer_to_a(index));
|
|
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_nl;
|
|
sappend(index->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 (index->b)
|
|
gen_and(index->b, b);
|
|
#ifdef INET6
|
|
gen_and(gen_proto_abbrev(Q_IP), b);
|
|
#endif
|
|
index->b = b;
|
|
break;
|
|
#ifdef INET6
|
|
case Q_ICMPV6:
|
|
bpf_error("IPv6 upper-layer protocol is not supported by proto[x]");
|
|
/*NOTREACHED*/
|
|
#endif
|
|
}
|
|
index->regno = regno;
|
|
s = new_stmt(BPF_ST);
|
|
s->s.k = regno;
|
|
sappend(index->s, s);
|
|
|
|
return index;
|
|
}
|
|
|
|
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 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:
|
|
if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX)
|
|
return gen_ahostop(abroadcast, Q_DST);
|
|
if (linktype == DLT_EN10MB)
|
|
return gen_ehostop(ebroadcast, Q_DST);
|
|
if (linktype == DLT_FDDI)
|
|
return gen_fhostop(ebroadcast, Q_DST);
|
|
if (linktype == DLT_IEEE802)
|
|
return gen_thostop(ebroadcast, Q_DST);
|
|
if (linktype == DLT_IEEE802_11 ||
|
|
linktype == DLT_IEEE802_11_RADIO_AVS ||
|
|
linktype == DLT_IEEE802_11_RADIO ||
|
|
linktype == DLT_PRISM_HEADER)
|
|
return gen_wlanhostop(ebroadcast, Q_DST);
|
|
if (linktype == DLT_IP_OVER_FC)
|
|
return gen_ipfchostop(ebroadcast, Q_DST);
|
|
if (linktype == DLT_SUNATM && 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;
|
|
}
|
|
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 */
|
|
}
|
|
|
|
/*
|
|
* 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:
|
|
if (linktype == DLT_ARCNET || linktype == DLT_ARCNET_LINUX)
|
|
/* all ARCnet multicasts use the same address */
|
|
return gen_ahostop(abroadcast, Q_DST);
|
|
|
|
if (linktype == DLT_EN10MB) {
|
|
/* ether[0] & 1 != 0 */
|
|
return gen_mac_multicast(0);
|
|
}
|
|
|
|
if (linktype == 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);
|
|
}
|
|
|
|
if (linktype == DLT_IEEE802) {
|
|
/* tr[2] & 1 != 0 */
|
|
return gen_mac_multicast(2);
|
|
}
|
|
|
|
if (linktype == DLT_IEEE802_11 ||
|
|
linktype == DLT_IEEE802_11_RADIO_AVS ||
|
|
linktype == DLT_IEEE802_11_RADIO ||
|
|
linktype == 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;
|
|
}
|
|
|
|
if (linktype == DLT_IP_OVER_FC) {
|
|
b0 = gen_mac_multicast(2);
|
|
return b0;
|
|
}
|
|
|
|
if (linktype == DLT_SUNATM && 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;
|
|
}
|
|
|
|
/* 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 */
|
|
}
|
|
|
|
/*
|
|
* 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:
|
|
/* 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 */
|
|
}
|
|
|
|
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_cmp(OR_LINK, off_linktype, BPF_H,
|
|
(bpf_int32)ETHERTYPE_MPLS);
|
|
break;
|
|
|
|
case DLT_PPP:
|
|
b0 = gen_cmp(OR_LINK, off_linktype, BPF_H,
|
|
(bpf_int32)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;
|
|
}
|
|
|
|
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;
|
|
}
|