1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
/*
* Small pcap precompiler
* Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <sys/types.h>
#include <sys/time.h>
#include <string.h>
#include <stdlib.h>
#include <pcap.h>
int main (int argc, char ** argv)
{
struct bpf_program filter;
pcap_t *pc;
int i;
if (argc != 2)
{
printf ("Usage: %s <expression>\n", argv[0]);
return 1;
}
pc = pcap_open_dead(DLT_EN10MB, 1500);
if (pcap_compile(pc, &filter, argv[1], 1, 0) != 0) {
printf("error in active-filter expression: %s\n", pcap_geterr(pc));
return 1;
}
printf("/* precompiled expression: %s */\n\n"
"static struct bpf_insn pktfilter_insns[] = {\n",
argv[1]);
for (i = 0; i < filter.bf_len; i++) {
struct bpf_insn *in = &filter.bf_insns[i];
printf("\t{ .code = 0x%04x, .jt = 0x%02x, .jf = 0x%02x, .k = 0x%08x },\n", in->code, in->jt, in->jf, in->k);
}
printf("};\n\n"
"static struct bpf_program pktfilter = {\n"
"\t.bf_len = %d,\n"
"\t.bf_insns = pktfilter_insns,\n"
"};\n", filter.bf_len);
return 0;
}
|
