src/capture-pkt.c

   1 /* For terms of usage/redistribution/modification see the LICENSE file */
   2 /* For authors and contributors see the AUTHORS file */
   3
   4 #include "iptraf-ng-compat.h"
   5
   6 #include "built-in.h"
   7 #include "parse-options.h"
   8 #include "ifaces.h"
   9 #include "packet.h"
  10 #include "capt.h"
  11
  12 static const char *const capture_usage[] = {
  13         IPTRAF_NAME " capture [-c] <device>",
  14         NULL
  15 };
  16
  17 static int cap_nr_pkt = 1, help_opt;
  18 static char *ofilename;
  19
  20 static struct options capture_options[] = {
  21         OPT__HELP(&help_opt),
  22         OPT_GROUP(""),
  23         OPT_INTEGER('c', "capture", &cap_nr_pkt, "capture <n> packets"),
  24         OPT_STRING('o', "output", &ofilename, "file", "save captured packet into <file>"),
  25         OPT_END()
  26 };
  27
  28 int cmd_capture(int argc, char **argv)
  29 {
  30         parse_opts(argc, argv, capture_options, capture_usage);
  31         argv += optind;
  32         if (help_opt || !*argv || argv[1])
  33                 parse_usage_and_die(capture_usage, capture_options);
  34
  35         char *dev = argv[0];
  36
  37         struct capt capt;
  38         if (capt_init(&capt, dev) == -1)
  39                 die_errno("Unable to initialize packet capture interface");
  40
  41         FILE *fp = NULL;
  42         if (ofilename) {
  43                 fp = fopen(ofilename, "wb");
  44                 if (!fp)
  45                         die_errno("fopen");
  46         }
  47
  48         struct pkt_hdr pkt;
  49         packet_init(&pkt);
  50
  51         int captured = 0;
  52         for (;;) {
  53                 if (capt_get_packet(&capt, &pkt, NULL, NULL) == -1)
  54                         die_errno("fail to get packet");
  55
  56                 if (!pkt.pkt_len)
  57                         continue;
  58
  59                 printf(".");
  60                 fflush(stdout);
  61
  62                 if (fp)
  63                         fwrite(&pkt, sizeof(pkt), 1, fp);
  64
  65                 capt_put_packet(&capt, &pkt);
  66
  67                 if (++captured == cap_nr_pkt)
  68                         break;
  69         }
  70         printf("\n");
  71
  72         packet_destroy(&pkt);
  73
  74         if (fp)
  75                 fclose(fp);
  76
  77         capt_destroy(&capt);
  78
  79         return 0;
  80 }