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 #include "varattrs.h"
  23
  24 #ifndef lint
  25 static const char copyright[] _U_ =
  26     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
  27 The Regents of the University of California.  All rights reserved.\n";
  28 #endif
  29
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <stdarg.h>
  34 #include <limits.h>
  35 #ifdef _WIN32
  36   #include "getopt.h"
  37 #else
  38   #include <unistd.h>
  39 #endif
  40 #include <errno.h>
  41 #include <sys/types.h>
  42
  43 #include <pcap.h>
  44
  45 #include "pcap/funcattrs.h"
  46
  47 #ifdef _WIN32
  48   #include "portability.h"
  49 #endif
  50
  51 static char *program_name;
  52
  53 /* Forwards */
  54 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
  55 static void PCAP_NORETURN usage(void);
  56 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  57 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  58 static char *copy_argv(char **);
  59
  60 static pcap_t *pd;
  61
  62 int
  63 main(int argc, char **argv)
  64 {
  65         register int op;
  66         register char *cp, *cmdbuf, *device;
  67         long longarg;
  68         char *p;
  69         int timeout = 1000;
  70         int immediate = 0;
  71         int nonblock = 0;
  72         pcap_if_t *devlist;
  73         bpf_u_int32 localnet, netmask;
  74         struct bpf_program fcode;
  75         char ebuf[PCAP_ERRBUF_SIZE];
  76         int status;
  77         int packet_count;
  78
  79         device = NULL;
  80         if ((cp = strrchr(argv[0], '/')) != NULL)
  81                 program_name = cp + 1;
  82         else
  83                 program_name = argv[0];
  84
  85         opterr = 0;
  86         while ((op = getopt(argc, argv, "i:mnt:")) != -1) {
  87                 switch (op) {
  88
  89                 case 'i':
  90                         device = optarg;
  91                         break;
  92
  93                 case 'm':
  94                         immediate = 1;
  95                         break;
  96
  97                 case 'n':
  98                         nonblock = 1;
  99                         break;
 100
 101                 case 't':
 102                         longarg = strtol(optarg, &p, 10);
 103                         if (p == optarg || *p != '\0') {
 104                                 error("Timeout value \"%s\" is not a number",
 105                                     optarg);
 106                                 /* NOTREACHED */
 107                         }
 108                         if (longarg < 0) {
 109                                 error("Timeout value %ld is negative", longarg);
 110                                 /* NOTREACHED */
 111                         }
 112                         if (longarg > INT_MAX) {
 113                                 error("Timeout value %ld is too large (> %d)",
 114                                     longarg, INT_MAX);
 115                                 /* NOTREACHED */
 116                         }
 117                         timeout = (int)longarg;
 118                         break;
 119
 120                 default:
 121                         usage();
 122                         /* NOTREACHED */
 123                 }
 124         }
 125
 126         if (device == NULL) {
 127                 if (pcap_findalldevs(&devlist, ebuf) == -1)
 128                         error("%s", ebuf);
 129                 if (devlist == NULL)
 130                         error("no interfaces available for capture");
 131                 device = strdup(devlist->name);
 132                 pcap_freealldevs(devlist);
 133         }
 134         *ebuf = '\0';
 135         pd = pcap_create(device, ebuf);
 136         if (pd == NULL)
 137                 error("%s", ebuf);
 138         status = pcap_set_snaplen(pd, 65535);
 139         if (status != 0)
 140                 error("%s: pcap_set_snaplen failed: %s",
 141                             device, pcap_statustostr(status));
 142         if (immediate) {
 143                 status = pcap_set_immediate_mode(pd, 1);
 144                 if (status != 0)
 145                         error("%s: pcap_set_immediate_mode failed: %s",
 146                             device, pcap_statustostr(status));
 147         }
 148         status = pcap_set_timeout(pd, timeout);
 149         if (status != 0)
 150                 error("%s: pcap_set_timeout failed: %s",
 151                     device, pcap_statustostr(status));
 152         status = pcap_activate(pd);
 153         if (status < 0) {
 154                 /*
 155                  * pcap_activate() failed.
 156                  */
 157                 error("%s: %s\n(%s)", device,
 158                     pcap_statustostr(status), pcap_geterr(pd));
 159         } else if (status > 0) {
 160                 /*
 161                  * pcap_activate() succeeded, but it's warning us
 162                  * of a problem it had.
 163                  */
 164                 warning("%s: %s\n(%s)", device,
 165                     pcap_statustostr(status), pcap_geterr(pd));
 166         }
 167         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 168                 localnet = 0;
 169                 netmask = 0;
 170                 warning("%s", ebuf);
 171         }
 172         cmdbuf = copy_argv(&argv[optind]);
 173
 174         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 175                 error("%s", pcap_geterr(pd));
 176
 177         if (pcap_setfilter(pd, &fcode) < 0)
 178                 error("%s", pcap_geterr(pd));
 179         if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
 180                 error("pcap_setnonblock failed: %s", ebuf);
 181         printf("Listening on %s\n", device);
 182         for (;;) {
 183                 packet_count = 0;
 184                 status = pcap_dispatch(pd, -1, countme,
 185                     (u_char *)&packet_count);
 186                 if (status < 0)
 187                         break;
 188                 if (status != 0) {
 189                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 190                             status, packet_count);
 191                 }
 192         }
 193         if (status == -2) {
 194                 /*
 195                  * We got interrupted, so perhaps we didn't
 196                  * manage to finish a line we were printing.
 197                  * Print an extra newline, just in case.
 198                  */
 199                 putchar('\n');
 200         }
 201         (void)fflush(stdout);
 202         if (status == -1) {
 203                 /*
 204                  * Error.  Report it.
 205                  */
 206                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 207                     program_name, pcap_geterr(pd));
 208         }
 209         pcap_close(pd);
 210         pcap_freecode(&fcode);
 211         free(cmdbuf);
 212         exit(status == -1 ? 1 : 0);
 213 }
 214
 215 static void
 216 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 217 {
 218         int *counterp = (int *)user;
 219
 220         (*counterp)++;
 221 }
 222
 223 static void
 224 usage(void)
 225 {
 226         (void)fprintf(stderr, "Usage: %s [ -mn ] [ -i interface ] [ -t timeout] [expression]\n",
 227             program_name);
 228         exit(1);
 229 }
 230
 231 /* VARARGS */
 232 static void
 233 error(const char *fmt, ...)
 234 {
 235         va_list ap;
 236
 237         (void)fprintf(stderr, "%s: ", program_name);
 238         va_start(ap, fmt);
 239         (void)vfprintf(stderr, fmt, ap);
 240         va_end(ap);
 241         if (*fmt) {
 242                 fmt += strlen(fmt);
 243                 if (fmt[-1] != '\n')
 244                         (void)fputc('\n', stderr);
 245         }
 246         exit(1);
 247         /* NOTREACHED */
 248 }
 249
 250 /* VARARGS */
 251 static void
 252 warning(const char *fmt, ...)
 253 {
 254         va_list ap;
 255
 256         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 257         va_start(ap, fmt);
 258         (void)vfprintf(stderr, fmt, ap);
 259         va_end(ap);
 260         if (*fmt) {
 261                 fmt += strlen(fmt);
 262                 if (fmt[-1] != '\n')
 263                         (void)fputc('\n', stderr);
 264         }
 265 }
 266
 267 /*
 268  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 269  */
 270 static char *
 271 copy_argv(register char **argv)
 272 {
 273         register char **p;
 274         register u_int len = 0;
 275         char *buf;
 276         char *src, *dst;
 277
 278         p = argv;
 279         if (*p == 0)
 280                 return 0;
 281
 282         while (*p)
 283                 len += strlen(*p++) + 1;
 284
 285         buf = (char *)malloc(len);
 286         if (buf == NULL)
 287                 error("copy_argv: malloc");
 288
 289         p = argv;
 290         dst = buf;
 291         while ((src = *p++) != NULL) {
 292                 while ((*dst++ = *src++) != '\0')
 293                         ;
 294                 dst[-1] = ' ';
 295         }
 296         dst[-1] = '\0';
 297
 298         return buf;
 299 }