1f503b4c4SSepherosa Ziehau #include <sys/types.h>
2f503b4c4SSepherosa Ziehau #include <sys/socket.h>
3f503b4c4SSepherosa Ziehau
4f503b4c4SSepherosa Ziehau #include <arpa/inet.h>
5f503b4c4SSepherosa Ziehau #include <netinet/in.h>
6f503b4c4SSepherosa Ziehau
7f503b4c4SSepherosa Ziehau #include <err.h>
8f503b4c4SSepherosa Ziehau #include <stdio.h>
9f503b4c4SSepherosa Ziehau #include <stdint.h>
10f503b4c4SSepherosa Ziehau #include <stdlib.h>
11f503b4c4SSepherosa Ziehau #include <string.h>
12f503b4c4SSepherosa Ziehau #include <unistd.h>
13f503b4c4SSepherosa Ziehau
14f503b4c4SSepherosa Ziehau static void
usage(const char * cmd)15f503b4c4SSepherosa Ziehau usage(const char *cmd)
16f503b4c4SSepherosa Ziehau {
17*c4122907SSepherosa Ziehau fprintf(stderr, "%s -4 ip4 -p port [-r]\n", cmd);
18f503b4c4SSepherosa Ziehau exit(1);
19f503b4c4SSepherosa Ziehau }
20f503b4c4SSepherosa Ziehau
21f503b4c4SSepherosa Ziehau int
main(int argc,char * argv[])22f503b4c4SSepherosa Ziehau main(int argc, char *argv[])
23f503b4c4SSepherosa Ziehau {
24f503b4c4SSepherosa Ziehau struct sockaddr_in in;
25*c4122907SSepherosa Ziehau int s, opt, n, reuseport;
26f503b4c4SSepherosa Ziehau uint8_t buf[18];
27f503b4c4SSepherosa Ziehau
28f503b4c4SSepherosa Ziehau memset(&in, 0, sizeof(in));
29f503b4c4SSepherosa Ziehau in.sin_family = AF_INET;
30f503b4c4SSepherosa Ziehau
31*c4122907SSepherosa Ziehau reuseport = 0;
32*c4122907SSepherosa Ziehau
33*c4122907SSepherosa Ziehau while ((opt = getopt(argc, argv, "4:p:r")) != -1) {
34f503b4c4SSepherosa Ziehau switch (opt) {
35f503b4c4SSepherosa Ziehau case '4':
36f503b4c4SSepherosa Ziehau if (inet_pton(AF_INET, optarg, &in.sin_addr) <= 0)
37f503b4c4SSepherosa Ziehau usage(argv[0]);
38f503b4c4SSepherosa Ziehau break;
39f503b4c4SSepherosa Ziehau
40f503b4c4SSepherosa Ziehau case 'p':
41f503b4c4SSepherosa Ziehau in.sin_port = strtol(optarg, NULL, 10);
42f503b4c4SSepherosa Ziehau in.sin_port = htons(in.sin_port);
43f503b4c4SSepherosa Ziehau break;
44f503b4c4SSepherosa Ziehau
45*c4122907SSepherosa Ziehau case 'r':
46*c4122907SSepherosa Ziehau reuseport = 1;
47*c4122907SSepherosa Ziehau break;
48*c4122907SSepherosa Ziehau
49f503b4c4SSepherosa Ziehau default:
50f503b4c4SSepherosa Ziehau usage(argv[0]);
51f503b4c4SSepherosa Ziehau }
52f503b4c4SSepherosa Ziehau }
53f503b4c4SSepherosa Ziehau
54f503b4c4SSepherosa Ziehau if (in.sin_addr.s_addr == INADDR_ANY || in.sin_port == 0)
55f503b4c4SSepherosa Ziehau usage(argv[0]);
56f503b4c4SSepherosa Ziehau
57f503b4c4SSepherosa Ziehau s = socket(AF_INET, SOCK_DGRAM, 0);
58f503b4c4SSepherosa Ziehau if (s < 0)
59f503b4c4SSepherosa Ziehau err(2, "socket failed");
60f503b4c4SSepherosa Ziehau
61*c4122907SSepherosa Ziehau if (reuseport) {
62*c4122907SSepherosa Ziehau if (setsockopt(s, SOL_SOCKET, SO_REUSEPORT,
63*c4122907SSepherosa Ziehau &reuseport, sizeof(reuseport)) < 0)
64*c4122907SSepherosa Ziehau err(2, "setsockopt SO_REUSEPORT failed");
65*c4122907SSepherosa Ziehau }
66*c4122907SSepherosa Ziehau
67f503b4c4SSepherosa Ziehau n = sendto(s, buf, sizeof(buf), 0,
68f503b4c4SSepherosa Ziehau (const struct sockaddr *)&in, sizeof(in));
69f503b4c4SSepherosa Ziehau if (n < 0)
70f503b4c4SSepherosa Ziehau err(2, "sendto failed");
71f503b4c4SSepherosa Ziehau else if (n != (int)sizeof(buf))
72f503b4c4SSepherosa Ziehau errx(2, "sent truncated data %d", n);
73f503b4c4SSepherosa Ziehau
74f503b4c4SSepherosa Ziehau n = read(s, buf, sizeof(buf));
75f503b4c4SSepherosa Ziehau if (n < 0)
76f503b4c4SSepherosa Ziehau err(2, "read failed");
77f503b4c4SSepherosa Ziehau printf("read %d, done\n", n);
78f503b4c4SSepherosa Ziehau
79f503b4c4SSepherosa Ziehau exit(0);
80f503b4c4SSepherosa Ziehau }
81