test/udp/mcastsend/mcastsend.c

   1 #include <sys/types.h>
   2 #include <sys/socket.h>
   3
   4 #include <arpa/inet.h>
   5 #include <netinet/in.h>
   6
   7 #include <err.h>
   8 #include <stdint.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <unistd.h>
  13
  14 static void
  15 usage(const char *cmd)
  16 {
  17         fprintf(stderr, "%s -p port -d dst -i addr [-P bind_port]\n", cmd);
  18         exit(1);
  19 }
  20
  21 int
  22 main(int argc, char *argv[])
  23 {
  24         struct sockaddr_in dst, local_in;
  25         struct in_addr iface;
  26         int s, opt, n, loop = 0;
  27         uint8_t buf[18];
  28
  29         memset(&dst, 0, sizeof(dst));
  30         dst.sin_family = AF_INET;
  31
  32         memset(&local_in, 0, sizeof(local_in));
  33         local_in.sin_family = AF_INET;
  34
  35         memset(&iface, 0, sizeof(iface));
  36
  37         while ((opt = getopt(argc, argv, "P:d:i:p:")) != -1) {
  38                 switch (opt) {
  39                 case 'P':
  40                         local_in.sin_port = strtol(optarg, NULL, 10);
  41                         local_in.sin_port = htons(local_in.sin_port);
  42                         break;
  43
  44                 case 'd':
  45                         if (inet_pton(AF_INET, optarg, &dst.sin_addr) <= 0)
  46                                 usage(argv[0]);
  47                         break;
  48
  49                 case 'i':
  50                         if (inet_pton(AF_INET, optarg, &iface) <= 0)
  51                                 usage(argv[0]);
  52                         break;
  53
  54                 case 'p':
  55                         dst.sin_port = strtol(optarg, NULL, 10);
  56                         dst.sin_port = htons(dst.sin_port);
  57                         break;
  58
  59                 default:
  60                         usage(argv[0]);
  61                 }
  62         }
  63
  64         if (iface.s_addr == INADDR_ANY ||
  65             dst.sin_addr.s_addr == INADDR_ANY || dst.sin_port == 0)
  66                 usage(argv[0]);
  67
  68         s = socket(AF_INET, SOCK_DGRAM, 0);
  69         if (s < 0)
  70                 err(2, "socket failed");
  71
  72         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF,
  73             &iface, sizeof(iface)) < 0)
  74                 err(2, "setsockopt IP_MULTICAST_IF failed");
  75
  76         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_LOOP,
  77             &loop, sizeof(loop)) < 0)
  78                 err(2, "setsockopt IP_MULTICAST_LOOP failed");
  79
  80         if (local_in.sin_port != 0) {
  81                 local_in.sin_addr = iface;
  82                 if (bind(s, (const struct sockaddr *)&local_in,
  83                     sizeof(local_in)) < 0)
  84                         err(2, "bind failed");
  85         }
  86
  87         n = sendto(s, buf, sizeof(buf), 0,
  88             (const struct sockaddr *)&dst, sizeof(dst));
  89         if (n < 0)
  90                 err(2, "sendto failed");
  91         else if (n < (int)sizeof(buf))
  92                 errx(2, "sent truncated data %d", n);
  93
  94         exit(0);
  95 }