The Tcpdump Group git mirrors - libpcap/blob - tests/capturetest.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 #ifndef lint
  23 static const char copyright[] _U_ =
  24     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
  25 The Regents of the University of California.  All rights reserved.\n";
  26 #endif
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <stdarg.h>
  32 #include <limits.h>
  33 #ifdef _WIN32
  34 #include "getopt.h"
  35 #else
  36 #include <unistd.h>
  37 #endif
  38 #include <errno.h>
  39 #include <sys/types.h>
  40
  41 #include <pcap.h>
  42
  43 #include "pcap/funcattrs.h"
  44
  45 static char *program_name;
  46
  47 /* Forwards */
  48 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
  49 static void PCAP_NORETURN usage(void);
  50 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  51 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  52 static char *copy_argv(char **);
  53
  54 static pcap_t *pd;
  55
  56 int
  57 main(int argc, char **argv)
  58 {
  59         register int op;
  60         register char *cp, *cmdbuf, *device;
  61         long longarg;
  62         char *p;
  63         int timeout = 1000;
  64         int immediate = 0;
  65         int nonblock = 0;
  66         pcap_if_t *devlist;
  67         bpf_u_int32 localnet, netmask;
  68         struct bpf_program fcode;
  69         char ebuf[PCAP_ERRBUF_SIZE];
  70         int status;
  71         int packet_count;
  72
  73         device = NULL;
  74         if ((cp = strrchr(argv[0], '/')) != NULL)
  75                 program_name = cp + 1;
  76         else
  77                 program_name = argv[0];
  78
  79         opterr = 0;
  80         while ((op = getopt(argc, argv, "i:mnt:")) != -1) {
  81                 switch (op) {
  82
  83                 case 'i':
  84                         device = optarg;
  85                         break;
  86
  87                 case 'm':
  88                         immediate = 1;
  89                         break;
  90
  91                 case 'n':
  92                         nonblock = 1;
  93                         break;
  94
  95                 case 't':
  96                         longarg = strtol(optarg, &p, 10);
  97                         if (p == optarg || *p != '\0') {
  98                                 error("Timeout value \"%s\" is not a number",
  99                                     optarg);
 100                                 /* NOTREACHED */
 101                         }
 102                         if (longarg < 0) {
 103                                 error("Timeout value %ld is negative", longarg);
 104                                 /* NOTREACHED */
 105                         }
 106                         if (longarg > INT_MAX) {
 107                                 error("Timeout value %ld is too large (> %d)",
 108                                     longarg, INT_MAX);
 109                                 /* NOTREACHED */
 110                         }
 111                         timeout = (int)longarg;
 112                         break;
 113
 114                 default:
 115                         usage();
 116                         /* NOTREACHED */
 117                 }
 118         }
 119
 120         if (device == NULL) {
 121                 if (pcap_findalldevs(&devlist, ebuf) == -1)
 122                         error("%s", ebuf);
 123                 if (devlist == NULL)
 124                         error("no interfaces available for capture");
 125                 device = strdup(devlist->name);
 126                 pcap_freealldevs(devlist);
 127         }
 128         *ebuf = '\0';
 129         pd = pcap_create(device, ebuf);
 130         if (pd == NULL)
 131                 error("%s", ebuf);
 132         status = pcap_set_snaplen(pd, 65535);
 133         if (status != 0)
 134                 error("%s: pcap_set_snaplen failed: %s",
 135                             device, pcap_statustostr(status));
 136         if (immediate) {
 137                 status = pcap_set_immediate_mode(pd, 1);
 138                 if (status != 0)
 139                         error("%s: pcap_set_immediate_mode failed: %s",
 140                             device, pcap_statustostr(status));
 141         }
 142         status = pcap_set_timeout(pd, timeout);
 143         if (status != 0)
 144                 error("%s: pcap_set_timeout failed: %s",
 145                     device, pcap_statustostr(status));
 146         status = pcap_activate(pd);
 147         if (status < 0) {
 148                 /*
 149                  * pcap_activate() failed.
 150                  */
 151                 error("%s: %s\n(%s)", device,
 152                     pcap_statustostr(status), pcap_geterr(pd));
 153         } else if (status > 0) {
 154                 /*
 155                  * pcap_activate() succeeded, but it's warning us
 156                  * of a problem it had.
 157                  */
 158                 warning("%s: %s\n(%s)", device,
 159                     pcap_statustostr(status), pcap_geterr(pd));
 160         }
 161         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 162                 localnet = 0;
 163                 netmask = 0;
 164                 warning("%s", ebuf);
 165         }
 166         cmdbuf = copy_argv(&argv[optind]);
 167
 168         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 169                 error("%s", pcap_geterr(pd));
 170
 171         if (pcap_setfilter(pd, &fcode) < 0)
 172                 error("%s", pcap_geterr(pd));
 173         if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
 174                 error("pcap_setnonblock failed: %s", ebuf);
 175         printf("Listening on %s\n", device);
 176         for (;;) {
 177                 packet_count = 0;
 178                 status = pcap_dispatch(pd, -1, countme,
 179                     (u_char *)&packet_count);
 180                 if (status < 0)
 181                         break;
 182                 if (status != 0) {
 183                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 184                             status, packet_count);
 185                 }
 186         }
 187         if (status == -2) {
 188                 /*
 189                  * We got interrupted, so perhaps we didn't
 190                  * manage to finish a line we were printing.
 191                  * Print an extra newline, just in case.
 192                  */
 193                 putchar('\n');
 194         }
 195         (void)fflush(stdout);
 196         if (status == -1) {
 197                 /*
 198                  * Error.  Report it.
 199                  */
 200                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 201                     program_name, pcap_geterr(pd));
 202         }
 203         pcap_close(pd);
 204         exit(status == -1 ? 1 : 0);
 205 }
 206
 207 static void
 208 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 209 {
 210         int *counterp = (int *)user;
 211
 212         (*counterp)++;
 213 }
 214
 215 static void
 216 usage(void)
 217 {
 218         (void)fprintf(stderr, "Usage: %s [ -mn ] [ -i interface ] [ -t timeout] [expression]\n",
 219             program_name);
 220         exit(1);
 221 }
 222
 223 /* VARARGS */
 224 static void
 225 error(const char *fmt, ...)
 226 {
 227         va_list ap;
 228
 229         (void)fprintf(stderr, "%s: ", program_name);
 230         va_start(ap, fmt);
 231         (void)vfprintf(stderr, fmt, ap);
 232         va_end(ap);
 233         if (*fmt) {
 234                 fmt += strlen(fmt);
 235                 if (fmt[-1] != '\n')
 236                         (void)fputc('\n', stderr);
 237         }
 238         exit(1);
 239         /* NOTREACHED */
 240 }
 241
 242 /* VARARGS */
 243 static void
 244 warning(const char *fmt, ...)
 245 {
 246         va_list ap;
 247
 248         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 249         va_start(ap, fmt);
 250         (void)vfprintf(stderr, fmt, ap);
 251         va_end(ap);
 252         if (*fmt) {
 253                 fmt += strlen(fmt);
 254                 if (fmt[-1] != '\n')
 255                         (void)fputc('\n', stderr);
 256         }
 257 }
 258
 259 /*
 260  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 261  */
 262 static char *
 263 copy_argv(register char **argv)
 264 {
 265         register char **p;
 266         register u_int len = 0;
 267         char *buf;
 268         char *src, *dst;
 269
 270         p = argv;
 271         if (*p == 0)
 272                 return 0;
 273
 274         while (*p)
 275                 len += strlen(*p++) + 1;
 276
 277         buf = (char *)malloc(len);
 278         if (buf == NULL)
 279                 error("copy_argv: malloc");
 280
 281         p = argv;
 282         dst = buf;
 283         while ((src = *p++) != NULL) {
 284                 while ((*dst++ = *src++) != '\0')
 285                         ;
 286                 dst[-1] = ' ';
 287         }
 288         dst[-1] = '\0';
 289
 290         return buf;
 291 }