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-rw-r--r--net/bpf_filter.c666
1 files changed, 0 insertions, 666 deletions
diff --git a/net/bpf_filter.c b/net/bpf_filter.c
deleted file mode 100644
index a2733d1..0000000
--- a/net/bpf_filter.c
+++ /dev/null
@@ -1,666 +0,0 @@
-/*-
- * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from the Stanford/CMU enet packet filter,
- * (net/enet.c) distributed as part of 4.3BSD, and code contributed
- * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
- * Berkeley Laboratory.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- * @(#)bpf.c 7.5 (Berkeley) 7/15/91
- */
-
-#if !(defined(lint) || defined(KERNEL) || defined(_KERNEL))
-static const char rcsid[] _U_ =
- "@(#) $Header: /tcpdump/master/libpcap/bpf/net/bpf_filter.c,v 1.45.2.1 2008/01/02 04:22:16 guy Exp $ (LBL)";
-#endif
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#ifdef WIN32
-
-#include <pcap-stdinc.h>
-
-#else /* WIN32 */
-
-#include <sys/param.h>
-#include <sys/types.h>
-#include <sys/time.h>
-
-#define SOLARIS (defined(sun) && (defined(__SVR4) || defined(__svr4__)))
-#if defined(__hpux) || SOLARIS
-# include <sys/sysmacros.h>
-# include <sys/stream.h>
-# define mbuf msgb
-# define m_next b_cont
-# define MLEN(m) ((m)->b_wptr - (m)->b_rptr)
-# define mtod(m,t) ((t)(m)->b_rptr)
-#else
-# define MLEN(m) ((m)->m_len)
-#endif
-
-#endif /* WIN32 */
-
-#include <pcap/bpf.h>
-
-#if !defined(KERNEL) && !defined(_KERNEL)
-#include <stdlib.h>
-#endif
-
-#define int32 bpf_int32
-#define u_int32 bpf_u_int32
-
-#ifndef LBL_ALIGN
-/*
- * XXX - IA-64? If not, this probably won't work on Win64 IA-64
- * systems, unless LBL_ALIGN is defined elsewhere for them.
- * XXX - SuperH? If not, this probably won't work on WinCE SuperH
- * systems, unless LBL_ALIGN is defined elsewhere for them.
- */
-#if defined(sparc) || defined(__sparc__) || defined(mips) || \
- defined(ibm032) || defined(__alpha) || defined(__hpux) || \
- defined(__arm__)
-#define LBL_ALIGN
-#endif
-#endif
-
-#ifndef LBL_ALIGN
-#ifndef WIN32
-#include <netinet/in.h>
-#endif
-
-#define EXTRACT_SHORT(p) ((u_short)ntohs(*(u_short *)p))
-#define EXTRACT_LONG(p) (ntohl(*(u_int32 *)p))
-#else
-#define EXTRACT_SHORT(p)\
- ((u_short)\
- ((u_short)*((u_char *)p+0)<<8|\
- (u_short)*((u_char *)p+1)<<0))
-#define EXTRACT_LONG(p)\
- ((u_int32)*((u_char *)p+0)<<24|\
- (u_int32)*((u_char *)p+1)<<16|\
- (u_int32)*((u_char *)p+2)<<8|\
- (u_int32)*((u_char *)p+3)<<0)
-#endif
-
-#if defined(KERNEL) || defined(_KERNEL)
-# if !defined(__hpux) && !SOLARIS
-#include <sys/mbuf.h>
-# endif
-#define MINDEX(len, _m, _k) \
-{ \
- len = MLEN(m); \
- while ((_k) >= len) { \
- (_k) -= len; \
- (_m) = (_m)->m_next; \
- if ((_m) == 0) \
- return 0; \
- len = MLEN(m); \
- } \
-}
-
-static int
-m_xword(m, k, err)
- register struct mbuf *m;
- register int k, *err;
-{
- register int len;
- register u_char *cp, *np;
- register struct mbuf *m0;
-
- MINDEX(len, m, k);
- cp = mtod(m, u_char *) + k;
- if (len - k >= 4) {
- *err = 0;
- return EXTRACT_LONG(cp);
- }
- m0 = m->m_next;
- if (m0 == 0 || MLEN(m0) + len - k < 4)
- goto bad;
- *err = 0;
- np = mtod(m0, u_char *);
- switch (len - k) {
-
- case 1:
- return (cp[0] << 24) | (np[0] << 16) | (np[1] << 8) | np[2];
-
- case 2:
- return (cp[0] << 24) | (cp[1] << 16) | (np[0] << 8) | np[1];
-
- default:
- return (cp[0] << 24) | (cp[1] << 16) | (cp[2] << 8) | np[0];
- }
- bad:
- *err = 1;
- return 0;
-}
-
-static int
-m_xhalf(m, k, err)
- register struct mbuf *m;
- register int k, *err;
-{
- register int len;
- register u_char *cp;
- register struct mbuf *m0;
-
- MINDEX(len, m, k);
- cp = mtod(m, u_char *) + k;
- if (len - k >= 2) {
- *err = 0;
- return EXTRACT_SHORT(cp);
- }
- m0 = m->m_next;
- if (m0 == 0)
- goto bad;
- *err = 0;
- return (cp[0] << 8) | mtod(m0, u_char *)[0];
- bad:
- *err = 1;
- return 0;
-}
-#endif
-
-/*
- * Execute the filter program starting at pc on the packet p
- * wirelen is the length of the original packet
- * buflen is the amount of data present
- * For the kernel, p is assumed to be a pointer to an mbuf if buflen is 0,
- * in all other cases, p is a pointer to a buffer and buflen is its size.
- */
-u_int
-bpf_filter(pc, p, wirelen, buflen)
- register const struct bpf_insn *pc;
- register const u_char *p;
- u_int wirelen;
- register u_int buflen;
-{
- register u_int32 A, X;
- register int k;
- int32 mem[BPF_MEMWORDS];
-#if defined(KERNEL) || defined(_KERNEL)
- struct mbuf *m, *n;
- int merr, len;
-
- if (buflen == 0) {
- m = (struct mbuf *)p;
- p = mtod(m, u_char *);
- buflen = MLEN(m);
- } else
- m = NULL;
-#endif
-
- if (pc == 0)
- /*
- * No filter means accept all.
- */
- return (u_int)-1;
- A = 0;
- X = 0;
- --pc;
- while (1) {
- ++pc;
- switch (pc->code) {
-
- default:
-#if defined(KERNEL) || defined(_KERNEL)
- return 0;
-#else
- abort();
-#endif
- case BPF_RET|BPF_K:
- return (u_int)pc->k;
-
- case BPF_RET|BPF_A:
- return (u_int)A;
-
- case BPF_LD|BPF_W|BPF_ABS:
- k = pc->k;
- if (k + sizeof(int32) > buflen) {
-#if defined(KERNEL) || defined(_KERNEL)
- if (m == NULL)
- return 0;
- A = m_xword(m, k, &merr);
- if (merr != 0)
- return 0;
- continue;
-#else
- return 0;
-#endif
- }
- A = EXTRACT_LONG(&p[k]);
- continue;
-
- case BPF_LD|BPF_H|BPF_ABS:
- k = pc->k;
- if (k + sizeof(short) > buflen) {
-#if defined(KERNEL) || defined(_KERNEL)
- if (m == NULL)
- return 0;
- A = m_xhalf(m, k, &merr);
- if (merr != 0)
- return 0;
- continue;
-#else
- return 0;
-#endif
- }
- A = EXTRACT_SHORT(&p[k]);
- continue;
-
- case BPF_LD|BPF_B|BPF_ABS:
- k = pc->k;
- if (k >= buflen) {
-#if defined(KERNEL) || defined(_KERNEL)
- if (m == NULL)
- return 0;
- n = m;
- MINDEX(len, n, k);
- A = mtod(n, u_char *)[k];
- continue;
-#else
- return 0;
-#endif
- }
- A = p[k];
- continue;
-
- case BPF_LD|BPF_W|BPF_LEN:
- A = wirelen;
- continue;
-
- case BPF_LDX|BPF_W|BPF_LEN:
- X = wirelen;
- continue;
-
- case BPF_LD|BPF_W|BPF_IND:
- k = X + pc->k;
- if (k + sizeof(int32) > buflen) {
-#if defined(KERNEL) || defined(_KERNEL)
- if (m == NULL)
- return 0;
- A = m_xword(m, k, &merr);
- if (merr != 0)
- return 0;
- continue;
-#else
- return 0;
-#endif
- }
- A = EXTRACT_LONG(&p[k]);
- continue;
-
- case BPF_LD|BPF_H|BPF_IND:
- k = X + pc->k;
- if (k + sizeof(short) > buflen) {
-#if defined(KERNEL) || defined(_KERNEL)
- if (m == NULL)
- return 0;
- A = m_xhalf(m, k, &merr);
- if (merr != 0)
- return 0;
- continue;
-#else
- return 0;
-#endif
- }
- A = EXTRACT_SHORT(&p[k]);
- continue;
-
- case BPF_LD|BPF_B|BPF_IND:
- k = X + pc->k;
- if (k >= buflen) {
-#if defined(KERNEL) || defined(_KERNEL)
- if (m == NULL)
- return 0;
- n = m;
- MINDEX(len, n, k);
- A = mtod(n, u_char *)[k];
- continue;
-#else
- return 0;
-#endif
- }
- A = p[k];
- continue;
-
- case BPF_LDX|BPF_MSH|BPF_B:
- k = pc->k;
- if (k >= buflen) {
-#if defined(KERNEL) || defined(_KERNEL)
- if (m == NULL)
- return 0;
- n = m;
- MINDEX(len, n, k);
- X = (mtod(n, char *)[k] & 0xf) << 2;
- continue;
-#else
- return 0;
-#endif
- }
- X = (p[pc->k] & 0xf) << 2;
- continue;
-
- case BPF_LD|BPF_IMM:
- A = pc->k;
- continue;
-
- case BPF_LDX|BPF_IMM:
- X = pc->k;
- continue;
-
- case BPF_LD|BPF_MEM:
- A = mem[pc->k];
- continue;
-
- case BPF_LDX|BPF_MEM:
- X = mem[pc->k];
- continue;
-
- case BPF_ST:
- mem[pc->k] = A;
- continue;
-
- case BPF_STX:
- mem[pc->k] = X;
- continue;
-
- case BPF_JMP|BPF_JA:
- pc += pc->k;
- continue;
-
- case BPF_JMP|BPF_JGT|BPF_K:
- pc += (A > pc->k) ? pc->jt : pc->jf;
- continue;
-
- case BPF_JMP|BPF_JGE|BPF_K:
- pc += (A >= pc->k) ? pc->jt : pc->jf;
- continue;
-
- case BPF_JMP|BPF_JEQ|BPF_K:
- pc += (A == pc->k) ? pc->jt : pc->jf;
- continue;
-
- case BPF_JMP|BPF_JSET|BPF_K:
- pc += (A & pc->k) ? pc->jt : pc->jf;
- continue;
-
- case BPF_JMP|BPF_JGT|BPF_X:
- pc += (A > X) ? pc->jt : pc->jf;
- continue;
-
- case BPF_JMP|BPF_JGE|BPF_X:
- pc += (A >= X) ? pc->jt : pc->jf;
- continue;
-
- case BPF_JMP|BPF_JEQ|BPF_X:
- pc += (A == X) ? pc->jt : pc->jf;
- continue;
-
- case BPF_JMP|BPF_JSET|BPF_X:
- pc += (A & X) ? pc->jt : pc->jf;
- continue;
-
- case BPF_ALU|BPF_ADD|BPF_X:
- A += X;
- continue;
-
- case BPF_ALU|BPF_SUB|BPF_X:
- A -= X;
- continue;
-
- case BPF_ALU|BPF_MUL|BPF_X:
- A *= X;
- continue;
-
- case BPF_ALU|BPF_DIV|BPF_X:
- if (X == 0)
- return 0;
- A /= X;
- continue;
-
- case BPF_ALU|BPF_AND|BPF_X:
- A &= X;
- continue;
-
- case BPF_ALU|BPF_OR|BPF_X:
- A |= X;
- continue;
-
- case BPF_ALU|BPF_LSH|BPF_X:
- A <<= X;
- continue;
-
- case BPF_ALU|BPF_RSH|BPF_X:
- A >>= X;
- continue;
-
- case BPF_ALU|BPF_ADD|BPF_K:
- A += pc->k;
- continue;
-
- case BPF_ALU|BPF_SUB|BPF_K:
- A -= pc->k;
- continue;
-
- case BPF_ALU|BPF_MUL|BPF_K:
- A *= pc->k;
- continue;
-
- case BPF_ALU|BPF_DIV|BPF_K:
- A /= pc->k;
- continue;
-
- case BPF_ALU|BPF_AND|BPF_K:
- A &= pc->k;
- continue;
-
- case BPF_ALU|BPF_OR|BPF_K:
- A |= pc->k;
- continue;
-
- case BPF_ALU|BPF_LSH|BPF_K:
- A <<= pc->k;
- continue;
-
- case BPF_ALU|BPF_RSH|BPF_K:
- A >>= pc->k;
- continue;
-
- case BPF_ALU|BPF_NEG:
- A = -A;
- continue;
-
- case BPF_MISC|BPF_TAX:
- X = A;
- continue;
-
- case BPF_MISC|BPF_TXA:
- A = X;
- continue;
- }
- }
-}
-
-/*
- * Return true if the 'fcode' is a valid filter program.
- * The constraints are that each jump be forward and to a valid
- * code, that memory accesses are within valid ranges (to the
- * extent that this can be checked statically; loads of packet
- * data have to be, and are, also checked at run time), and that
- * the code terminates with either an accept or reject.
- *
- * The kernel needs to be able to verify an application's filter code.
- * Otherwise, a bogus program could easily crash the system.
- */
-int
-bpf_validate(f, len)
- const struct bpf_insn *f;
- int len;
-{
- u_int i, from;
- const struct bpf_insn *p;
-
- if (len < 1)
- return 0;
- /*
- * There's no maximum program length in userland.
- */
-#if defined(KERNEL) || defined(_KERNEL)
- if (len > BPF_MAXINSNS)
- return 0;
-#endif
-
- for (i = 0; i < len; ++i) {
- p = &f[i];
- switch (BPF_CLASS(p->code)) {
- /*
- * Check that memory operations use valid addresses.
- */
- case BPF_LD:
- case BPF_LDX:
- switch (BPF_MODE(p->code)) {
- case BPF_IMM:
- break;
- case BPF_ABS:
- case BPF_IND:
- case BPF_MSH:
- /*
- * There's no maximum packet data size
- * in userland. The runtime packet length
- * check suffices.
- */
-#if defined(KERNEL) || defined(_KERNEL)
- /*
- * More strict check with actual packet length
- * is done runtime.
- */
- if (p->k >= bpf_maxbufsize)
- return 0;
-#endif
- break;
- case BPF_MEM:
- if (p->k >= BPF_MEMWORDS)
- return 0;
- break;
- case BPF_LEN:
- break;
- default:
- return 0;
- }
- break;
- case BPF_ST:
- case BPF_STX:
- if (p->k >= BPF_MEMWORDS)
- return 0;
- break;
- case BPF_ALU:
- switch (BPF_OP(p->code)) {
- case BPF_ADD:
- case BPF_SUB:
- case BPF_MUL:
- case BPF_OR:
- case BPF_AND:
- case BPF_LSH:
- case BPF_RSH:
- case BPF_NEG:
- break;
- case BPF_DIV:
- /*
- * Check for constant division by 0.
- */
- if (BPF_RVAL(p->code) == BPF_K && p->k == 0)
- return 0;
- break;
- default:
- return 0;
- }
- break;
- case BPF_JMP:
- /*
- * Check that jumps are within the code block,
- * and that unconditional branches don't go
- * backwards as a result of an overflow.
- * Unconditional branches have a 32-bit offset,
- * so they could overflow; we check to make
- * sure they don't. Conditional branches have
- * an 8-bit offset, and the from address is <=
- * BPF_MAXINSNS, and we assume that BPF_MAXINSNS
- * is sufficiently small that adding 255 to it
- * won't overflow.
- *
- * We know that len is <= BPF_MAXINSNS, and we
- * assume that BPF_MAXINSNS is < the maximum size
- * of a u_int, so that i + 1 doesn't overflow.
- *
- * For userland, we don't know that the from
- * or len are <= BPF_MAXINSNS, but we know that
- * from <= len, and, except on a 64-bit system,
- * it's unlikely that len, if it truly reflects
- * the size of the program we've been handed,
- * will be anywhere near the maximum size of
- * a u_int. We also don't check for backward
- * branches, as we currently support them in
- * userland for the protochain operation.
- */
- from = i + 1;
- switch (BPF_OP(p->code)) {
- case BPF_JA:
-#if defined(KERNEL) || defined(_KERNEL)
- if (from + p->k < from || from + p->k >= len)
-#else
- if (from + p->k >= len)
-#endif
- return 0;
- break;
- case BPF_JEQ:
- case BPF_JGT:
- case BPF_JGE:
- case BPF_JSET:
- if (from + p->jt >= len || from + p->jf >= len)
- return 0;
- break;
- default:
- return 0;
- }
- break;
- case BPF_RET:
- break;
- case BPF_MISC:
- break;
- default:
- return 0;
- }
- }
- return BPF_CLASS(f[len - 1].code) == BPF_RET;
-}
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