The Tcpdump Group git mirrors - libpcap/blob - testprogs/writecaptest.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 #ifndef _WIN32
  42   #include <signal.h>
  43 #endif
  44 #include <sys/types.h>
  45
  46 #include <pcap.h>
  47
  48 #include "pcap/funcattrs.h"
  49
  50 #ifdef _WIN32
  51   #include "portability.h"
  52 #endif
  53
  54 static char *program_name;
  55
  56 /* Forwards */
  57 static void PCAP_NORETURN usage(void);
  58 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  59 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  60 static char *copy_argv(char **);
  61
  62 static pcap_t *pd;
  63
  64 #ifdef _WIN32
  65 static BOOL WINAPI
  66 stop_capture(DWORD ctrltype _U_)
  67 {
  68         pcap_breakloop(pd);
  69         return TRUE;
  70 }
  71 #else
  72 static void
  73 stop_capture(int signum _U_)
  74 {
  75         pcap_breakloop(pd);
  76 }
  77 #endif
  78
  79 #define COMMAND_OPTIONS "Li:w:y:"
  80
  81 int
  82 main(int argc, char **argv)
  83 {
  84         register int op;
  85         register char *cp, *cmdbuf, *device, *savefile = NULL;
  86         pcap_if_t *devlist;
  87         int show_dlt_types = 0;
  88         int ndlts;
  89         int *dlts;
  90         bpf_u_int32 localnet, netmask;
  91         struct bpf_program fcode;
  92         char ebuf[PCAP_ERRBUF_SIZE];
  93 #ifndef _WIN32
  94         struct sigaction action;
  95 #endif
  96         int dlt;
  97         const char *dlt_name = NULL;
  98         int status;
  99         pcap_dumper_t *pdd;
 100
 101         device = NULL;
 102         if ((cp = strrchr(argv[0], '/')) != NULL)
 103                 program_name = cp + 1;
 104         else
 105                 program_name = argv[0];
 106
 107         opterr = 0;
 108         while ((op = getopt(argc, argv, COMMAND_OPTIONS)) != -1) {
 109                 switch (op) {
 110
 111                 case 'L':
 112                         show_dlt_types = 1;
 113                         break;
 114
 115                 case 'i':
 116                         device = optarg;
 117                         break;
 118
 119                 case 'w':
 120                         savefile = optarg;
 121                         break;
 122
 123                 case 'y':
 124                         dlt_name = optarg;
 125                         break;
 126
 127                 default:
 128                         usage();
 129                         /* NOTREACHED */
 130                 }
 131         }
 132
 133         if (device == NULL) {
 134                 if (pcap_findalldevs(&devlist, ebuf) == -1)
 135                         error("%s", ebuf);
 136                 if (devlist == NULL)
 137                         error("no interfaces available for capture");
 138                 device = strdup(devlist->name);
 139                 pcap_freealldevs(devlist);
 140         }
 141         if (show_dlt_types) {
 142                 pd = pcap_create(device, ebuf);
 143                 if (pd == NULL)
 144                         error("%s", ebuf);
 145                 status = pcap_activate(pd);
 146                 if (status < 0) {
 147                         /*
 148                          * pcap_activate() failed.
 149                          */
 150                         error("%s: %s\n(%s)", device,
 151                             pcap_statustostr(status), pcap_geterr(pd));
 152                 }
 153                 ndlts = pcap_list_datalinks(pd, &dlts);
 154                 if (ndlts < 0) {
 155                         /*
 156                          * pcap_list_datalinks() failed.
 157                          */
 158                         error("%s: %s\n(%s)", device,
 159                             pcap_statustostr(status), pcap_geterr(pd));
 160                 }
 161                 for (int i = 0; i < ndlts; i++) {
 162                         dlt_name = pcap_datalink_val_to_name(dlts[i]);
 163                         if (dlt_name == NULL)
 164                                 printf("DLT %d", dlts[i]);
 165                         else
 166                                 printf("%s", dlt_name);
 167                         printf("\n");
 168                 }
 169                 pcap_free_datalinks(dlts);
 170                 pcap_close(pd);
 171                 return 0;
 172         }
 173
 174         if (savefile == NULL)
 175                 error("no savefile specified");
 176
 177         *ebuf = '\0';
 178
 179         pd = pcap_create(device, ebuf);
 180         if (pd == NULL)
 181                 error("%s", ebuf);
 182         status = pcap_set_snaplen(pd, 262144);
 183         if (status != 0)
 184                 error("%s: pcap_set_snaplen failed: %s",
 185                             device, pcap_statustostr(status));
 186         status = pcap_set_timeout(pd, 100);
 187         if (status != 0)
 188                 error("%s: pcap_set_timeout failed: %s",
 189                     device, pcap_statustostr(status));
 190         status = pcap_activate(pd);
 191         if (status < 0) {
 192                 /*
 193                  * pcap_activate() failed.
 194                  */
 195                 error("%s: %s\n(%s)", device,
 196                     pcap_statustostr(status), pcap_geterr(pd));
 197         } else if (status > 0) {
 198                 /*
 199                  * pcap_activate() succeeded, but it's warning us
 200                  * of a problem it had.
 201                  */
 202                 warning("%s: %s\n(%s)", device,
 203                     pcap_statustostr(status), pcap_geterr(pd));
 204         }
 205         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 206                 localnet = 0;
 207                 netmask = 0;
 208                 warning("%s", ebuf);
 209         }
 210
 211         if (dlt_name != NULL) {
 212                 dlt = pcap_datalink_name_to_val(dlt_name);
 213                 if (dlt == PCAP_ERROR)
 214                         error("%s isn't a valid DLT name", dlt_name);
 215                 if (pcap_set_datalink(pd, dlt) == PCAP_ERROR)
 216                         error("%s: %s", device, pcap_geterr(pd));
 217         }
 218
 219         cmdbuf = copy_argv(&argv[optind]);
 220
 221         if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
 222                 error("%s", pcap_geterr(pd));
 223
 224         if (pcap_setfilter(pd, &fcode) < 0)
 225                 error("%s", pcap_geterr(pd));
 226
 227         pdd = pcap_dump_open(pd, savefile);
 228         if (pdd == NULL)
 229                 error("%s", pcap_geterr(pd));
 230
 231 #ifdef _WIN32
 232         SetConsoleCtrlHandler(stop_capture, TRUE);
 233 #else
 234         action.sa_handler = stop_capture;
 235         sigemptyset(&action.sa_mask);
 236         action.sa_flags = 0;
 237         if (sigaction(SIGINT, &action, NULL) == -1)
 238                 error("Can't catch SIGINT: %s\n", strerror(errno));
 239 #endif
 240
 241         printf("Listening on %s, link-type ", device);
 242         dlt = pcap_datalink(pd);
 243         dlt_name = pcap_datalink_val_to_name(dlt);
 244         if (dlt_name == NULL)
 245                 printf("DLT %d", dlt);
 246         else
 247                 printf("%s", dlt_name);
 248         printf("\n");
 249         for (;;) {
 250                 status = pcap_dispatch(pd, -1, pcap_dump, (u_char *)pdd);
 251                 if (status < 0)
 252                         break;
 253                 if (status != 0) {
 254                         printf("%d packets seen\n", status);
 255                         struct pcap_stat ps;
 256                         pcap_stats(pd, &ps);
 257                         printf("%d ps_recv, %d ps_drop, %d ps_ifdrop\n",
 258                             ps.ps_recv, ps.ps_drop, ps.ps_ifdrop);
 259                 }
 260         }
 261         if (status == -2) {
 262                 /*
 263                  * We got interrupted, so perhaps we didn't
 264                  * manage to finish a line we were printing.
 265                  * Print an extra newline, just in case.
 266                  */
 267                 putchar('\n');
 268                 printf("Broken out of loop from SIGINT handler\n");
 269         }
 270         (void)fflush(stdout);
 271         if (status == -1) {
 272                 /*
 273                  * Error.  Report it.
 274                  */
 275                 (void)fprintf(stderr, "%s: pcap_dispatch: %s\n",
 276                     program_name, pcap_geterr(pd));
 277         }
 278         pcap_close(pd);
 279         pcap_freecode(&fcode);
 280         free(cmdbuf);
 281         exit(status == -1 ? 1 : 0);
 282 }
 283
 284 static void
 285 usage(void)
 286 {
 287         (void)fprintf(stderr, "Usage: %s -L [ -i interface ] [ -w file ] [ -y dlt ] [expression]\n",
 288             program_name);
 289         exit(1);
 290 }
 291
 292 /* VARARGS */
 293 static void
 294 error(const char *fmt, ...)
 295 {
 296         va_list ap;
 297
 298         (void)fprintf(stderr, "%s: ", program_name);
 299         va_start(ap, fmt);
 300         (void)vfprintf(stderr, fmt, ap);
 301         va_end(ap);
 302         if (*fmt) {
 303                 fmt += strlen(fmt);
 304                 if (fmt[-1] != '\n')
 305                         (void)fputc('\n', stderr);
 306         }
 307         exit(1);
 308         /* NOTREACHED */
 309 }
 310
 311 /* VARARGS */
 312 static void
 313 warning(const char *fmt, ...)
 314 {
 315         va_list ap;
 316
 317         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 318         va_start(ap, fmt);
 319         (void)vfprintf(stderr, fmt, ap);
 320         va_end(ap);
 321         if (*fmt) {
 322                 fmt += strlen(fmt);
 323                 if (fmt[-1] != '\n')
 324                         (void)fputc('\n', stderr);
 325         }
 326 }
 327
 328 /*
 329  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 330  */
 331 static char *
 332 copy_argv(register char **argv)
 333 {
 334         register char **p;
 335         register size_t len = 0;
 336         char *buf;
 337         char *src, *dst;
 338
 339         p = argv;
 340         if (*p == 0)
 341                 return 0;
 342
 343         while (*p)
 344                 len += strlen(*p++) + 1;
 345
 346         buf = (char *)malloc(len);
 347         if (buf == NULL)
 348                 error("copy_argv: malloc");
 349
 350         p = argv;
 351         dst = buf;
 352         while ((src = *p++) != NULL) {
 353                 while ((*dst++ = *src++) != '\0')
 354                         ;
 355                 dst[-1] = ' ';
 356         }
 357         dst[-1] = '\0';
 358
 359         return buf;
 360 }