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[] =
  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 #ifndef _WIN32
  34 #include <unistd.h>
  35 #endif
  36 #include <errno.h>
  37 #include <sys/types.h>
  38 #ifndef _WIN32
  39 #include <sys/select.h>
  40 #include <poll.h>
  41 #endif
  42
  43 #include <pcap.h>
  44
  45 static char *program_name;
  46
  47 #if defined( _MSC_VER )
  48 #  define PCAP_NORETURN __declspec(noreturn)
  49 #elif defined( __GNUC__ )
  50 #  define PCAP_NORETURN __attribute__((noreturn))
  51 #else
  52 #  define PCAP_NORETURN
  53 #endif
  54
  55 /* Forwards */
  56 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
  57 static void PCAP_NORETURN usage(void);
  58 static void error(const char *, ...);
  59 static void warning(const char *, ...);
  60 static char *copy_argv(char **);
  61
  62 static pcap_t *pd;
  63
  64 extern int optind;
  65 extern int opterr;
  66 extern char *optarg;
  67
  68 int
  69 main(int argc, char **argv)
  70 {
  71         register int op;
  72         register char *cp, *cmdbuf, *device;
  73         long longarg;
  74         char *p;
  75         int timeout = 1000;
  76         int immediate = 0;
  77         int nonblock = 0;
  78         bpf_u_int32 localnet, netmask;
  79         struct bpf_program fcode;
  80         char ebuf[PCAP_ERRBUF_SIZE];
  81         int status;
  82         int packet_count;
  83
  84         device = NULL;
  85         if ((cp = strrchr(argv[0], '/')) != NULL)
  86                 program_name = cp + 1;
  87         else
  88                 program_name = argv[0];
  89
  90         opterr = 0;
  91         while ((op = getopt(argc, argv, "i:mnt:")) != -1) {
  92                 switch (op) {
  93
  94                 case 'i':
  95                         device = optarg;
  96                         break;
  97
  98                 case 'm':
  99                         immediate = 1;
 100                         break;
 101
 102                 case 'n':
 103                         nonblock = 1;
 104                         break;
 105
 106                 case 't':
 107                         longarg = strtol(optarg, &p, 10);
 108                         if (p == optarg || *p != '\0') {
 109                                 error("Timeout value \"%s\" is not a number",
 110                                     optarg);
 111                                 /* NOTREACHED */
 112                         }
 113                         if (longarg < 0) {
 114                                 error("Timeout value %ld is negative", longarg);
 115                                 /* NOTREACHED */
 116                         }
 117                         if (longarg > INT_MAX) {
 118                                 error("Timeout value %ld is too large (> %d)",
 119                                     longarg, INT_MAX);
 120                                 /* NOTREACHED */
 121                         }
 122                         timeout = (int)longarg;
 123                         break;
 124
 125                 default:
 126                         usage();
 127                         /* NOTREACHED */
 128                 }
 129         }
 130
 131         if (device == NULL) {
 132                 device = pcap_lookupdev(ebuf);
 133                 if (device == NULL)
 134                         error("%s", ebuf);
 135         }
 136         *ebuf = '\0';
 137         pd = pcap_create(device, ebuf);
 138         if (pd == NULL)
 139                 error("%s", ebuf);
 140         status = pcap_set_snaplen(pd, 65535);
 141         if (status != 0)
 142                 error("%s: pcap_set_snaplen failed: %s",
 143                             device, pcap_statustostr(status));
 144         if (immediate) {
 145                 status = pcap_set_immediate_mode(pd, 1);
 146                 if (status != 0)
 147                         error("%s: pcap_set_immediate_mode failed: %s",
 148                             device, pcap_statustostr(status));
 149         }
 150         status = pcap_set_timeout(pd, timeout);
 151         if (status != 0)
 152                 error("%s: pcap_set_timeout failed: %s",
 153                     device, pcap_statustostr(status));
 154         status = pcap_activate(pd);
 155         if (status < 0) {
 156                 /*
 157                  * pcap_activate() failed.
 158                  */
 159                 error("%s: %s\n(%s)", device,
 160                     pcap_statustostr(status), pcap_geterr(pd));
 161         } else if (status > 0) {
 162                 /*
 163                  * pcap_activate() succeeded, but it's warning us
 164                  * of a problem it had.
 165                  */
 166                 warning("%s: %s\n(%s)", device,
 167                     pcap_statustostr(status), pcap_geterr(pd));
 168         }
 169         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 170                 localnet = 0;
 171                 netmask = 0;
 172                 warning("%s", ebuf);
 173         }
 174         cmdbuf = copy_argv(&argv[optind]);
 175
 176         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 177                 error("%s", pcap_geterr(pd));
 178
 179         if (pcap_setfilter(pd, &fcode) < 0)
 180                 error("%s", pcap_geterr(pd));
 181         if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
 182                 error("pcap_setnonblock failed: %s", ebuf);
 183         printf("Listening on %s\n", device);
 184         for (;;) {
 185                 packet_count = 0;
 186                 status = pcap_dispatch(pd, -1, countme,
 187                     (u_char *)&packet_count);
 188                 if (status < 0)
 189                         break;
 190                 if (status != 0) {
 191                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 192                             status, packet_count);
 193                 }
 194         }
 195         if (status == -2) {
 196                 /*
 197                  * We got interrupted, so perhaps we didn't
 198                  * manage to finish a line we were printing.
 199                  * Print an extra newline, just in case.
 200                  */
 201                 putchar('\n');
 202         }
 203         (void)fflush(stdout);
 204         if (status == -1) {
 205                 /*
 206                  * Error.  Report it.
 207                  */
 208                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 209                     program_name, pcap_geterr(pd));
 210         }
 211         pcap_close(pd);
 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 }