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Upgrade libpcap to version 1.0.0.

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This commit is contained in:
david
2009-10-27 19:33:50 +00:00
parent a56ff60c50
commit 9a1ec98da3
145 changed files with 22384 additions and 17731 deletions
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169
libpcap/bpf/net/bpf_filter.c
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@@ -40,7 +40,7 @@
#if !(defined(lint) || defined(KERNEL) || defined(_KERNEL))
static const char rcsid[] _U_ =
"@(#) $Header: /tcpdump/master/libpcap/bpf/net/bpf_filter.c,v 1.44 2003/11/15 23:24:07 guy Exp $ (LBL)";
"@(#) $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
@@ -71,7 +71,7 @@ static const char rcsid[] _U_ =
#endif /* WIN32 */
#include <pcap-bpf.h>
#include <pcap/bpf.h>
#if !defined(KERNEL) && !defined(_KERNEL)
#include <stdlib.h>
@@ -200,8 +200,8 @@ m_xhalf(m, k, err)
*/
u_int
bpf_filter(pc, p, wirelen, buflen)
register struct bpf_insn *pc;
register u_char *p;
register const struct bpf_insn *pc;
register const u_char *p;
u_int wirelen;
register u_int buflen;
{
@@ -512,54 +512,155 @@ bpf_filter(pc, p, wirelen, buflen)
}
}
/*
* Return true if the 'fcode' is a valid filter program.
* The constraints are that each jump be forward and to a valid
* code. The code must terminate with either an accept or reject.
* 'valid' is an array for use by the routine (it must be at least
* 'len' bytes long).
* 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)
struct bpf_insn *f;
const struct bpf_insn *f;
int len;
{
register int i;
register struct bpf_insn *p;
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) {
/*
* Check that that jumps are forward, and within
* the code block.
*/
p = &f[i];
if (BPF_CLASS(p->code) == BPF_JMP) {
register int from = i + 1;
if (BPF_OP(p->code) == BPF_JA) {
if (from + p->k >= (unsigned)len)
return 0;
}
else if (from + p->jt >= len || from + p->jf >= len)
return 0;
}
switch (BPF_CLASS(p->code)) {
/*
* Check that memory operations use valid addresses.
*/
if ((BPF_CLASS(p->code) == BPF_ST ||
(BPF_CLASS(p->code) == BPF_LD &&
(p->code & 0xe0) == BPF_MEM)) &&
(p->k >= BPF_MEMWORDS || p->k < 0))
return 0;
/*
* Check for constant division by 0.
*/
if (p->code == (BPF_ALU|BPF_DIV|BPF_K) && p->k == 0)
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;
}