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 #ifdef _WIN32
  46   #include "portability.h"
  47 #endif
  48
  49 static char *program_name;
  50
  51 /* Forwards */
  52 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
  53 static void PCAP_NORETURN usage(void);
  54 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  55 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  56 static char *copy_argv(char **);
  57
  58 static pcap_t *pd;
  59
  60 int
  61 main(int argc, char **argv)
  62 {
  63         register int op;
  64         register char *cp, *cmdbuf, *device;
  65         long longarg;
  66         char *p;
  67         int timeout = 1000;
  68         int immediate = 0;
  69         int nonblock = 0;
  70         pcap_if_t *devlist;
  71         bpf_u_int32 localnet, netmask;
  72         struct bpf_program fcode;
  73         char ebuf[PCAP_ERRBUF_SIZE];
  74         int status;
  75         int packet_count;
  76
  77         device = NULL;
  78         if ((cp = strrchr(argv[0], '/')) != NULL)
  79                 program_name = cp + 1;
  80         else
  81                 program_name = argv[0];
  82
  83         opterr = 0;
  84         while ((op = getopt(argc, argv, "i:mnt:")) != -1) {
  85                 switch (op) {
  86
  87                 case 'i':
  88                         device = optarg;
  89                         break;
  90
  91                 case 'm':
  92                         immediate = 1;
  93                         break;
  94
  95                 case 'n':
  96                         nonblock = 1;
  97                         break;
  98
  99                 case 't':
 100                         longarg = strtol(optarg, &p, 10);
 101                         if (p == optarg || *p != '\0') {
 102                                 error("Timeout value \"%s\" is not a number",
 103                                     optarg);
 104                                 /* NOTREACHED */
 105                         }
 106                         if (longarg < 0) {
 107                                 error("Timeout value %ld is negative", longarg);
 108                                 /* NOTREACHED */
 109                         }
 110                         if (longarg > INT_MAX) {
 111                                 error("Timeout value %ld is too large (> %d)",
 112                                     longarg, INT_MAX);
 113                                 /* NOTREACHED */
 114                         }
 115                         timeout = (int)longarg;
 116                         break;
 117
 118                 default:
 119                         usage();
 120                         /* NOTREACHED */
 121                 }
 122         }
 123
 124         if (device == NULL) {
 125                 if (pcap_findalldevs(&devlist, ebuf) == -1)
 126                         error("%s", ebuf);
 127                 if (devlist == NULL)
 128                         error("no interfaces available for capture");
 129                 device = strdup(devlist->name);
 130                 pcap_freealldevs(devlist);
 131         }
 132         *ebuf = '\0';
 133         pd = pcap_create(device, ebuf);
 134         if (pd == NULL)
 135                 error("%s", ebuf);
 136         status = pcap_set_snaplen(pd, 65535);
 137         if (status != 0)
 138                 error("%s: pcap_set_snaplen failed: %s",
 139                             device, pcap_statustostr(status));
 140         if (immediate) {
 141                 status = pcap_set_immediate_mode(pd, 1);
 142                 if (status != 0)
 143                         error("%s: pcap_set_immediate_mode failed: %s",
 144                             device, pcap_statustostr(status));
 145         }
 146         status = pcap_set_timeout(pd, timeout);
 147         if (status != 0)
 148                 error("%s: pcap_set_timeout failed: %s",
 149                     device, pcap_statustostr(status));
 150         status = pcap_activate(pd);
 151         if (status < 0) {
 152                 /*
 153                  * pcap_activate() failed.
 154                  */
 155                 error("%s: %s\n(%s)", device,
 156                     pcap_statustostr(status), pcap_geterr(pd));
 157         } else if (status > 0) {
 158                 /*
 159                  * pcap_activate() succeeded, but it's warning us
 160                  * of a problem it had.
 161                  */
 162                 warning("%s: %s\n(%s)", device,
 163                     pcap_statustostr(status), pcap_geterr(pd));
 164         }
 165         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 166                 localnet = 0;
 167                 netmask = 0;
 168                 warning("%s", ebuf);
 169         }
 170         cmdbuf = copy_argv(&argv[optind]);
 171
 172         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 173                 error("%s", pcap_geterr(pd));
 174
 175         if (pcap_setfilter(pd, &fcode) < 0)
 176                 error("%s", pcap_geterr(pd));
 177         if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
 178                 error("pcap_setnonblock failed: %s", ebuf);
 179         printf("Listening on %s\n", device);
 180         for (;;) {
 181                 packet_count = 0;
 182                 status = pcap_dispatch(pd, -1, countme,
 183                     (u_char *)&packet_count);
 184                 if (status < 0)
 185                         break;
 186                 if (status != 0) {
 187                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 188                             status, packet_count);
 189                 }
 190         }
 191         if (status == -2) {
 192                 /*
 193                  * We got interrupted, so perhaps we didn't
 194                  * manage to finish a line we were printing.
 195                  * Print an extra newline, just in case.
 196                  */
 197                 putchar('\n');
 198         }
 199         (void)fflush(stdout);
 200         if (status == -1) {
 201                 /*
 202                  * Error.  Report it.
 203                  */
 204                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 205                     program_name, pcap_geterr(pd));
 206         }
 207         pcap_close(pd);
 208         pcap_freecode(&fcode);
 209         free(cmdbuf);
 210         exit(status == -1 ? 1 : 0);
 211 }
 212
 213 static void
 214 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 215 {
 216         int *counterp = (int *)user;
 217
 218         (*counterp)++;
 219 }
 220
 221 static void
 222 usage(void)
 223 {
 224         (void)fprintf(stderr, "Usage: %s [ -mn ] [ -i interface ] [ -t timeout] [expression]\n",
 225             program_name);
 226         exit(1);
 227 }
 228
 229 /* VARARGS */
 230 static void
 231 error(const char *fmt, ...)
 232 {
 233         va_list ap;
 234
 235         (void)fprintf(stderr, "%s: ", program_name);
 236         va_start(ap, fmt);
 237         (void)vfprintf(stderr, fmt, ap);
 238         va_end(ap);
 239         if (*fmt) {
 240                 fmt += strlen(fmt);
 241                 if (fmt[-1] != '\n')
 242                         (void)fputc('\n', stderr);
 243         }
 244         exit(1);
 245         /* NOTREACHED */
 246 }
 247
 248 /* VARARGS */
 249 static void
 250 warning(const char *fmt, ...)
 251 {
 252         va_list ap;
 253
 254         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 255         va_start(ap, fmt);
 256         (void)vfprintf(stderr, fmt, ap);
 257         va_end(ap);
 258         if (*fmt) {
 259                 fmt += strlen(fmt);
 260                 if (fmt[-1] != '\n')
 261                         (void)fputc('\n', stderr);
 262         }
 263 }
 264
 265 /*
 266  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 267  */
 268 static char *
 269 copy_argv(register char **argv)
 270 {
 271         register char **p;
 272         register u_int len = 0;
 273         char *buf;
 274         char *src, *dst;
 275
 276         p = argv;
 277         if (*p == 0)
 278                 return 0;
 279
 280         while (*p)
 281                 len += strlen(*p++) + 1;
 282
 283         buf = (char *)malloc(len);
 284         if (buf == NULL)
 285                 error("copy_argv: malloc");
 286
 287         p = argv;
 288         dst = buf;
 289         while ((src = *p++) != NULL) {
 290                 while ((*dst++ = *src++) != '\0')
 291                         ;
 292                 dst[-1] = ' ';
 293         }
 294         dst[-1] = '\0';
 295
 296         return buf;
 297 }