2 * Copyright (c) 2014 Spectra Logic Corporation
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions, and the following disclaimer,
10 * without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 * substantially similar to the "NO WARRANTY" disclaimer below
13 * ("Disclaimer") and any redistribution must be conditioned upon
14 * including a substantially similar Disclaimer requirement for further
15 * binary redistribution.
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGES.
30 * Authors: Alan Somers (Spectra Logic Corporation)
35 #include <arpa/inet.h>
36 #include <netinet/in.h>
37 #include <sys/types.h>
38 #include <sys/socket.h>
50 * Sends a single UDP packet to the provided address, with SO_DONTROUTE set
51 * I couldn't find a way to do this with builtin utilities like nc(1)
54 main(int argc, char **argv)
56 struct sockaddr_storage dst;
61 const char* sendbuf = "Hello, World!";
62 const size_t buflen = 80;
65 const char *addr, *tapdev;
66 const uint16_t port = 46120;
68 bzero(&dst, sizeof(dst));
69 if (argc < 3 || argc > 4) {
70 fprintf(stderr, "Usage: %s [-6] ip_address tapdev\n", argv[0]);
74 if (strcmp("-6", argv[1]) == 0) {
83 t = open(tapdev, O_RDWR | O_NONBLOCK);
85 err(EXIT_FAILURE, "open");
88 s = socket(PF_INET6, SOCK_DGRAM, 0);
90 s = socket(PF_INET, SOCK_DGRAM, 0);
92 err(EXIT_FAILURE, "socket");
95 ret = setsockopt(s, SOL_SOCKET, SO_DONTROUTE, &opt, sizeof(opt));
97 err(EXIT_FAILURE, "setsockopt(SO_DONTROUTE)");
100 struct sockaddr_in6 *dst6 = ((struct sockaddr_in6*)&dst);
102 dst.ss_len = sizeof(struct sockaddr_in6);
103 dst.ss_family = AF_INET6;
104 dst6->sin6_port = htons(port);
105 ret = inet_pton(AF_INET6, addr, &dst6->sin6_addr);
107 struct sockaddr_in *dst4 = ((struct sockaddr_in*)&dst);
109 dst.ss_len = sizeof(struct sockaddr_in);
110 dst.ss_family = AF_INET;
111 dst4->sin_port = htons(port);
112 ret = inet_pton(AF_INET, addr, &dst4->sin_addr);
115 err(EXIT_FAILURE, "inet_pton returned %d", ret);
117 ret = sendto(s, sendbuf, strlen(sendbuf), 0, (struct sockaddr*)&dst,
120 err(EXIT_FAILURE, "sendto");
122 /* Verify that the packet went to the desired tap device */
124 len = read(t, recvbuf, buflen);
126 errx(EXIT_FAILURE, "read returned EOF");
127 else if (len < 0 && errno == EAGAIN)
128 errx(EXIT_FAILURE, "Did not receive any packets");
130 err(EXIT_FAILURE, "read");
133 * If read returned anything at all, consider it a success. The packet
134 * should be an Ethernet frame containing an ARP request for
135 * ip_address. We won't bother to decode it