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/*
* netsniff-ng - the packet sniffing beast
* Copyright 2011 Daniel Borkmann <dborkma@tik.ee.ethz.ch>,
* Swiss federal institute of technology (ETH Zurich)
* Subject to the GPL, version 2.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <getopt.h>
#include <ctype.h>
#include <unistd.h>
#include <sys/fsuid.h>
#include "xmalloc.h"
#include "die.h"
#include "bpf.h"
#include "config.h"
#include "str.h"
static const char *short_options = "vhi:Vdbf:pD:";
static const struct option long_options[] = {
{"input", required_argument, NULL, 'i'},
{"format", required_argument, NULL, 'f'},
{"cpp", no_argument, NULL, 'p'},
{"define", required_argument, NULL, 'D'},
{"verbose", no_argument, NULL, 'V'},
{"bypass", no_argument, NULL, 'b'},
{"dump", no_argument, NULL, 'd'},
{"version", no_argument, NULL, 'v'},
{"help", no_argument, NULL, 'h'},
{NULL, 0, NULL, 0}
};
static const char *copyright = "Please report bugs to <netsniff-ng@googlegroups.com>\n"
"Copyright (C) 2011-2013 Daniel Borkmann <dborkma@tik.ee.ethz.ch>,\n"
"Swiss federal institute of technology (ETH Zurich)\n"
"License: GNU GPL version 2.0\n"
"This is free software: you are free to change and redistribute it.\n"
"There is NO WARRANTY, to the extent permitted by law.";
extern int compile_filter(char *file, int verbose, int bypass, int format,
bool invoke_cpp, char **cpp_argv);
static void __noreturn help(void)
{
printf("bpfc %s, a tiny BPF compiler\n", VERSION_STRING);
puts("http://www.netsniff-ng.org\n\n"
"Usage: bpfc [options] || bpfc <program>\n"
"Options:\n"
" -i|--input <program/-> Berkeley Packet Filter file/stdin\n"
" -p|--cpp Run bpf program through C preprocessor\n"
" -D|--define Add macro/define for C preprocessor\n"
" -f|--format <format> Output format: C|netsniff-ng|xt_bpf|tcpdump\n"
" -b|--bypass Bypass filter validation (e.g. for bug testing)\n"
" -V|--verbose Be more verbose\n"
" -d|--dump Dump supported instruction table\n"
" -v|--version Print version and exit\n"
" -h|--help Print this help and exit\n\n"
"Examples:\n"
" bpfc fubar\n"
" bpfc fubar > foo (bpfc -f C -i fubar > foo) --> netsniff-ng -f foo ...\n"
" bpfc -f tcpdump -i fubar > foo --> tcpdump -ddd like ...\n"
" bpfc -f xt_bpf -b -p -i fubar\n"
" iptables -A INPUT -m bpf --bytecode \"`./bpfc -f xt_bpf -i fubar`\" -j LOG\n"
" bpfc - (read from stdin)\n"
"Note:\n"
" Generation of seccomp-BPF filters are fully supported as well.\n");
puts(copyright);
die();
}
static void __noreturn version(void)
{
printf("bpfc %s, Git id: %s\n", VERSION_LONG, GITVERSION);
puts("a tiny BPF compiler\n"
"http://www.netsniff-ng.org\n");
puts(copyright);
die();
}
int main(int argc, char **argv)
{
int ret, verbose = 0, c, opt_index, bypass = 0, format = 0;
bool invoke_cpp = false;
char **cpp_argv = NULL;
size_t cpp_argc = 0;
char *file = NULL;
setfsuid(getuid());
setfsgid(getgid());
if (argc == 1)
help();
while ((c = getopt_long(argc, argv, short_options,
long_options, &opt_index)) != EOF) {
switch (c) {
case 'h':
help();
break;
case 'v':
version();
break;
case 'V':
verbose = 1;
break;
case 'p':
invoke_cpp = true;
break;
case 'D':
cpp_argv = argv_insert(cpp_argv, &cpp_argc, "-D");
cpp_argv = argv_insert(cpp_argv, &cpp_argc, optarg);
break;
case 'f':
if (!strncmp(optarg, "C", 1) ||
!strncmp(optarg, "netsniff-ng", 11))
format = 0;
else if (!strncmp(optarg, "tcpdump", 7))
format = 2;
else if (!strncmp(optarg, "xt_bpf", 6) ||
!strncmp(optarg, "tc", 2))
format = 1;
else
help();
break;
case 'b':
bypass = 1;
break;
case 'd':
bpf_dump_op_table();
die();
case 'i':
file = xstrdup(optarg);
break;
case '?':
switch (optopt) {
case 'i':
case 'f':
panic("Option -%c requires an argument!\n",
optopt);
default:
if (isprint(optopt))
printf("Unknown option character `0x%X\'!\n", optopt);
die();
}
default:
break;
}
}
if (argc == 2)
file = xstrdup(argv[1]);
if (!file)
panic("No Berkeley Packet Filter program specified!\n");
ret = compile_filter(file, verbose, bypass, format, invoke_cpp, cpp_argv);
argv_free(cpp_argv);
xfree(file);
return ret;
}
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