#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
The Regents of the University of California. All rights reserved.\n";
#endif
#include <pcap.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/select.h>
#include <poll.h>
char *program_name;
static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
static void usage(void) __attribute__((noreturn));
static void error(const char *, ...);
static void warning(const char *, ...);
static char *copy_argv(char **);
static pcap_t *pd;
extern int optind;
extern int opterr;
extern char *optarg;
int
main(int argc, char **argv)
{
register int op;
bpf_u_int32 localnet, netmask;
register char *cp, *cmdbuf, *device;
struct bpf_program fcode;
char ebuf[PCAP_ERRBUF_SIZE];
int status;
int packet_count;
device = NULL;
if ((cp = strrchr(argv[0], '/')) != NULL)
program_name = cp + 1;
else
program_name = argv[0];
opterr = 0;
while ((op = getopt(argc, argv, "i:")) != -1) {
switch (op) {
case 'i':
device = optarg;
break;
default:
usage();
}
}
if (device == NULL) {
device = pcap_lookupdev(ebuf);
if (device == NULL)
error("%s", ebuf);
}
*ebuf = '\0';
pd = pcap_open_live(device, 65535, 0, 1000, ebuf);
if (pd == NULL)
error("%s", ebuf);
else if (*ebuf)
warning("%s", ebuf);
if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
localnet = 0;
netmask = 0;
warning("%s", ebuf);
}
cmdbuf = copy_argv(&argv[optind]);
if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
error("%s", pcap_geterr(pd));
if (pcap_setfilter(pd, &fcode) < 0)
error("%s", pcap_geterr(pd));
if (pcap_setnonblock(pd, 1, ebuf) == -1)
error("pcap_setnonblock failed: %s", ebuf);
printf("Listening on %s\n", device);
for (;;) {
packet_count = 0;
status = pcap_dispatch(pd, -1, countme,
(u_char *)&packet_count);
if (status < 0)
break;
if (status != 0) {
printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
status, packet_count);
}
}
if (status == -2) {
putchar('\n');
}
(void)fflush(stdout);
if (status == -1) {
(void)fprintf(stderr, "%s: pcap_loop: %s\n",
program_name, pcap_geterr(pd));
}
pcap_close(pd);
exit(status == -1 ? 1 : 0);
}
static void
countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
{
int *counterp = (int *)user;
(*counterp)++;
}
static void
usage(void)
{
(void)fprintf(stderr, "Usage: %s [ -sptn ] [ -i interface ] [expression]\n",
program_name);
exit(1);
}
static void
error(const char *fmt, ...)
{
va_list ap;
(void)fprintf(stderr, "%s: ", program_name);
va_start(ap, fmt);
(void)vfprintf(stderr, fmt, ap);
va_end(ap);
if (*fmt) {
fmt += strlen(fmt);
if (fmt[-1] != '\n')
(void)fputc('\n', stderr);
}
exit(1);
}
static void
warning(const char *fmt, ...)
{
va_list ap;
(void)fprintf(stderr, "%s: WARNING: ", program_name);
va_start(ap, fmt);
(void)vfprintf(stderr, fmt, ap);
va_end(ap);
if (*fmt) {
fmt += strlen(fmt);
if (fmt[-1] != '\n')
(void)fputc('\n', stderr);
}
}
static char *
copy_argv(register char **argv)
{
register char **p;
register u_int len = 0;
char *buf;
char *src, *dst;
p = argv;
if (*p == 0)
return 0;
while (*p)
len += strlen(*p++) + 1;
buf = (char *)malloc(len);
if (buf == NULL)
error("copy_argv: malloc");
p = argv;
dst = buf;
while ((src = *p++) != NULL) {
while ((*dst++ = *src++) != '\0')
;
dst[-1] = ' ';
}
dst[-1] = '\0';
return buf;
}