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 /*
  46  * This was introduced by Clang:
  47  *
  48  *     http://clang.llvm.org/docs/LanguageExtensions.html#has-attribute
  49  *
  50  * in some version (which version?); it has been picked up by GCC 5.0.
  51  */
  52 #ifndef __has_attribute
  53   /*
  54    * It's a macro, so you can check whether it's defined to check
  55    * whether it's supported.
  56    *
  57    * If it's not, define it to always return 0, so that we move on to
  58    * the fallback checks.
  59    */
  60   #define __has_attribute(x) 0
  61 #endif
  62
  63 #if __has_attribute(noreturn) \
  64     || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 205)) \
  65     || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590)) \
  66     || (defined(__xlC__) && __xlC__ >= 0x0A01) \
  67     || (defined(__HP_aCC) && __HP_aCC >= 61000)
  68   /*
  69    * Compiler with support for it, or GCC 2.5 and later, or Solaris Studio 12
  70    * (Sun C 5.9) and later, or IBM XL C 10.1 and later (do any earlier
  71    * versions of XL C support this?), or HP aCC A.06.10 and later.
  72    */
  73   #define PCAP_NORETURN __attribute((noreturn))
  74 #elif defined( _MSC_VER )
  75   #define PCAP_NORETURN __declspec(noreturn)
  76 #else
  77   #define PCAP_NORETURN
  78 #endif
  79
  80 #if __has_attribute(__format__) \
  81     || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 203)) \
  82     || (defined(__xlC__) && __xlC__ >= 0x0A01) \
  83     || (defined(__HP_aCC) && __HP_aCC >= 61000)
  84   /*
  85    * Compiler with support for it, or GCC 2.3 and later, or IBM XL C 10.1
  86    * and later (do any earlier versions of XL C support this?),
  87    * or HP aCC A.06.10 and later.
  88    */
  89   #define PCAP_PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y)))
  90 #else
  91   #define PCAP_PRINTFLIKE(x,y)
  92 #endif
  93
  94 /* Forwards */
  95 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);
  96 static void PCAP_NORETURN usage(void);
  97 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  98 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  99 static char *copy_argv(char **);
 100
 101 static pcap_t *pd;
 102
 103 int
 104 main(int argc, char **argv)
 105 {
 106         register int op;
 107         register char *cp, *cmdbuf, *device;
 108         long longarg;
 109         char *p;
 110         int timeout = 1000;
 111         int immediate = 0;
 112         int nonblock = 0;
 113         bpf_u_int32 localnet, netmask;
 114         struct bpf_program fcode;
 115         char ebuf[PCAP_ERRBUF_SIZE];
 116         int status;
 117         int packet_count;
 118
 119         device = NULL;
 120         if ((cp = strrchr(argv[0], '/')) != NULL)
 121                 program_name = cp + 1;
 122         else
 123                 program_name = argv[0];
 124
 125         opterr = 0;
 126         while ((op = getopt(argc, argv, "i:mnt:")) != -1) {
 127                 switch (op) {
 128
 129                 case 'i':
 130                         device = optarg;
 131                         break;
 132
 133                 case 'm':
 134                         immediate = 1;
 135                         break;
 136
 137                 case 'n':
 138                         nonblock = 1;
 139                         break;
 140
 141                 case 't':
 142                         longarg = strtol(optarg, &p, 10);
 143                         if (p == optarg || *p != '\0') {
 144                                 error("Timeout value \"%s\" is not a number",
 145                                     optarg);
 146                                 /* NOTREACHED */
 147                         }
 148                         if (longarg < 0) {
 149                                 error("Timeout value %ld is negative", longarg);
 150                                 /* NOTREACHED */
 151                         }
 152                         if (longarg > INT_MAX) {
 153                                 error("Timeout value %ld is too large (> %d)",
 154                                     longarg, INT_MAX);
 155                                 /* NOTREACHED */
 156                         }
 157                         timeout = (int)longarg;
 158                         break;
 159
 160                 default:
 161                         usage();
 162                         /* NOTREACHED */
 163                 }
 164         }
 165
 166         if (device == NULL) {
 167                 device = pcap_lookupdev(ebuf);
 168                 if (device == NULL)
 169                         error("%s", ebuf);
 170         }
 171         *ebuf = '\0';
 172         pd = pcap_create(device, ebuf);
 173         if (pd == NULL)
 174                 error("%s", ebuf);
 175         status = pcap_set_snaplen(pd, 65535);
 176         if (status != 0)
 177                 error("%s: pcap_set_snaplen failed: %s",
 178                             device, pcap_statustostr(status));
 179         if (immediate) {
 180                 status = pcap_set_immediate_mode(pd, 1);
 181                 if (status != 0)
 182                         error("%s: pcap_set_immediate_mode failed: %s",
 183                             device, pcap_statustostr(status));
 184         }
 185         status = pcap_set_timeout(pd, timeout);
 186         if (status != 0)
 187                 error("%s: pcap_set_timeout failed: %s",
 188                     device, pcap_statustostr(status));
 189         status = pcap_activate(pd);
 190         if (status < 0) {
 191                 /*
 192                  * pcap_activate() failed.
 193                  */
 194                 error("%s: %s\n(%s)", device,
 195                     pcap_statustostr(status), pcap_geterr(pd));
 196         } else if (status > 0) {
 197                 /*
 198                  * pcap_activate() succeeded, but it's warning us
 199                  * of a problem it had.
 200                  */
 201                 warning("%s: %s\n(%s)", device,
 202                     pcap_statustostr(status), pcap_geterr(pd));
 203         }
 204         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 205                 localnet = 0;
 206                 netmask = 0;
 207                 warning("%s", ebuf);
 208         }
 209         cmdbuf = copy_argv(&argv[optind]);
 210
 211         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 212                 error("%s", pcap_geterr(pd));
 213
 214         if (pcap_setfilter(pd, &fcode) < 0)
 215                 error("%s", pcap_geterr(pd));
 216         if (pcap_setnonblock(pd, nonblock, ebuf) == -1)
 217                 error("pcap_setnonblock failed: %s", ebuf);
 218         printf("Listening on %s\n", device);
 219         for (;;) {
 220                 packet_count = 0;
 221                 status = pcap_dispatch(pd, -1, countme,
 222                     (u_char *)&packet_count);
 223                 if (status < 0)
 224                         break;
 225                 if (status != 0) {
 226                         printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",
 227                             status, packet_count);
 228                 }
 229         }
 230         if (status == -2) {
 231                 /*
 232                  * We got interrupted, so perhaps we didn't
 233                  * manage to finish a line we were printing.
 234                  * Print an extra newline, just in case.
 235                  */
 236                 putchar('\n');
 237         }
 238         (void)fflush(stdout);
 239         if (status == -1) {
 240                 /*
 241                  * Error.  Report it.
 242                  */
 243                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 244                     program_name, pcap_geterr(pd));
 245         }
 246         pcap_close(pd);
 247         exit(status == -1 ? 1 : 0);
 248 }
 249
 250 static void
 251 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 252 {
 253         int *counterp = (int *)user;
 254
 255         (*counterp)++;
 256 }
 257
 258 static void
 259 usage(void)
 260 {
 261         (void)fprintf(stderr, "Usage: %s [ -mn ] [ -i interface ] [ -t timeout] [expression]\n",
 262             program_name);
 263         exit(1);
 264 }
 265
 266 /* VARARGS */
 267 static void
 268 error(const char *fmt, ...)
 269 {
 270         va_list ap;
 271
 272         (void)fprintf(stderr, "%s: ", program_name);
 273         va_start(ap, fmt);
 274         (void)vfprintf(stderr, fmt, ap);
 275         va_end(ap);
 276         if (*fmt) {
 277                 fmt += strlen(fmt);
 278                 if (fmt[-1] != '\n')
 279                         (void)fputc('\n', stderr);
 280         }
 281         exit(1);
 282         /* NOTREACHED */
 283 }
 284
 285 /* VARARGS */
 286 static void
 287 warning(const char *fmt, ...)
 288 {
 289         va_list ap;
 290
 291         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 292         va_start(ap, fmt);
 293         (void)vfprintf(stderr, fmt, ap);
 294         va_end(ap);
 295         if (*fmt) {
 296                 fmt += strlen(fmt);
 297                 if (fmt[-1] != '\n')
 298                         (void)fputc('\n', stderr);
 299         }
 300 }
 301
 302 /*
 303  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 304  */
 305 static char *
 306 copy_argv(register char **argv)
 307 {
 308         register char **p;
 309         register u_int len = 0;
 310         char *buf;
 311         char *src, *dst;
 312
 313         p = argv;
 314         if (*p == 0)
 315                 return 0;
 316
 317         while (*p)
 318                 len += strlen(*p++) + 1;
 319
 320         buf = (char *)malloc(len);
 321         if (buf == NULL)
 322                 error("copy_argv: malloc");
 323
 324         p = argv;
 325         dst = buf;
 326         while ((src = *p++) != NULL) {
 327                 while ((*dst++ = *src++) != '\0')
 328                         ;
 329                 dst[-1] = ' ';
 330         }
 331         dst[-1] = '\0';
 332
 333         return buf;
 334 }