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 static char *program_name;
  44
  45 #if defined( _MSC_VER )
  46 #  define PCAP_NORETURN __declspec(noreturn)
  47 #elif defined( __GNUC__ )
  48 #  define PCAP_NORETURN __attribute__((noreturn))
  49 #else
  50 #  define PCAP_NORETURN
  51 #endif
  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 error(const char *, ...);
  57 static void warning(const char *, ...);
  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         bpf_u_int32 localnet, netmask;
  73         struct bpf_program fcode;
  74         char ebuf[PCAP_ERRBUF_SIZE];
  75         int status;
  76         int packet_count;
  77
  78         device = NULL;
  79         if ((cp = strrchr(argv[0], '/')) != NULL)
  80                 program_name = cp + 1;
  81         else
  82                 program_name = argv[0];
  83
  84         opterr = 0;
  85         while ((op = getopt(argc, argv, "i:mnt:")) != -1) {
  86                 switch (op) {
  87
  88                 case 'i':
  89                         device = optarg;
  90                         break;
  91
  92                 case 'm':
  93                         immediate = 1;
  94                         break;
  95
  96                 case 'n':
  97                         nonblock = 1;
  98                         break;
  99
 100                 case 't':
 101                         longarg = strtol(optarg, &p, 10);
 102                         if (p == optarg || *p != '\0') {
 103                                 error("Timeout value \"%s\" is not a number",
 104                                     optarg);
 105                                 /* NOTREACHED */
 106                         }
 107                         if (longarg < 0) {
 108                                 error("Timeout value %ld is negative", longarg);
 109                                 /* NOTREACHED */
 110                         }
 111                         if (longarg > INT_MAX) {
 112                                 error("Timeout value %ld is too large (> %d)",
 113                                     longarg, INT_MAX);
 114                                 /* NOTREACHED */
 115                         }
 116                         timeout = (int)longarg;
 117                         break;
 118
 119                 default:
 120                         usage();
 121                         /* NOTREACHED */
 122                 }
 123         }
 124
 125         if (device == NULL) {
 126                 device = pcap_lookupdev(ebuf);
 127                 if (device == NULL)
 128                         error("%s", ebuf);
 129         }
 130         *ebuf = '\0';
 131         pd = pcap_create(device, ebuf);
 132         if (pd == NULL)
 133                 error("%s", ebuf);
 134         status = pcap_set_snaplen(pd, 65535);
 135         if (status != 0)
 136                 error("%s: pcap_set_snaplen failed: %s",
 137                             device, pcap_statustostr(status));
 138         if (immediate) {
 139                 status = pcap_set_immediate_mode(pd, 1);
 140                 if (status != 0)
 141                         error("%s: pcap_set_immediate_mode failed: %s",
 142                             device, pcap_statustostr(status));
 143         }
 144         status = pcap_set_timeout(pd, timeout);
 145         if (status != 0)
 146                 error("%s: pcap_set_timeout failed: %s",
 147                     device, pcap_statustostr(status));
 148         status = pcap_activate(pd);
 149         if (status < 0) {
 150                 /*
 151                  * pcap_activate() failed.
 152                  */
 153                 error("%s: %s\n(%s)", device,
 154                     pcap_statustostr(status), pcap_geterr(pd));
 155         } else if (status > 0) {
 156                 /*
 157                  * pcap_activate() succeeded, but it's warning us
 158                  * of a problem it had.
 159                  */
 160                 warning("%s: %s\n(%s)", device,
 161                     pcap_statustostr(status), pcap_geterr(pd));
 162         }
 163         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 164                 localnet = 0;
 165                 netmask = 0;
 166                 warning("%s", ebuf);
 167         }
 168         cmdbuf = copy_argv(&argv[optind]);
 169
 170         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 171                 error("%s", pcap_geterr(pd));
 172
 173         if (pcap_setfilter(pd, &fcode) < 0)
 174                 error("%s", pcap_geterr(pd));
 175         if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
 176                 error("pcap_setnonblock failed: %s", ebuf);
 177         printf("Listening on %s\n", device);
 178         for (;;) {
 179                 packet_count = 0;
 180                 status = pcap_dispatch(pd, -1, countme,
 181                     (u_char *)&packet_count);
 182                 if (status < 0)
 183                         break;
 184                 if (status != 0) {
 185                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 186                             status, packet_count);
 187                 }
 188         }
 189         if (status == -2) {
 190                 /*
 191                  * We got interrupted, so perhaps we didn't
 192                  * manage to finish a line we were printing.
 193                  * Print an extra newline, just in case.
 194                  */
 195                 putchar('\n');
 196         }
 197         (void)fflush(stdout);
 198         if (status == -1) {
 199                 /*
 200                  * Error.  Report it.
 201                  */
 202                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 203                     program_name, pcap_geterr(pd));
 204         }
 205         pcap_close(pd);
 206         exit(status == -1 ? 1 : 0);
 207 }
 208
 209 static void
 210 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 211 {
 212         int *counterp = (int *)user;
 213
 214         (*counterp)++;
 215 }
 216
 217 static void
 218 usage(void)
 219 {
 220         (void)fprintf(stderr, "Usage: %s [ -mn ] [ -i interface ] [ -t timeout] [expression]\n",
 221             program_name);
 222         exit(1);
 223 }
 224
 225 /* VARARGS */
 226 static void
 227 error(const char *fmt, ...)
 228 {
 229         va_list ap;
 230
 231         (void)fprintf(stderr, "%s: ", program_name);
 232         va_start(ap, fmt);
 233         (void)vfprintf(stderr, fmt, ap);
 234         va_end(ap);
 235         if (*fmt) {
 236                 fmt += strlen(fmt);
 237                 if (fmt[-1] != '\n')
 238                         (void)fputc('\n', stderr);
 239         }
 240         exit(1);
 241         /* NOTREACHED */
 242 }
 243
 244 /* VARARGS */
 245 static void
 246 warning(const char *fmt, ...)
 247 {
 248         va_list ap;
 249
 250         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 251         va_start(ap, fmt);
 252         (void)vfprintf(stderr, fmt, ap);
 253         va_end(ap);
 254         if (*fmt) {
 255                 fmt += strlen(fmt);
 256                 if (fmt[-1] != '\n')
 257                         (void)fputc('\n', stderr);
 258         }
 259 }
 260
 261 /*
 262  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 263  */
 264 static char *
 265 copy_argv(register char **argv)
 266 {
 267         register char **p;
 268         register u_int len = 0;
 269         char *buf;
 270         char *src, *dst;
 271
 272         p = argv;
 273         if (*p == 0)
 274                 return 0;
 275
 276         while (*p)
 277                 len += strlen(*p++) + 1;
 278
 279         buf = (char *)malloc(len);
 280         if (buf == NULL)
 281                 error("copy_argv: malloc");
 282
 283         p = argv;
 284         dst = buf;
 285         while ((src = *p++) != NULL) {
 286                 while ((*dst++ = *src++) != '\0')
 287                         ;
 288                 dst[-1] = ' ';
 289         }
 290         dst[-1] = '\0';
 291
 292         return buf;
 293 }