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>
49 * Sends a single UDP packet to the provided address, with SO_DONTROUTE set
50 * I couldn't find a way to do this with builtin utilities like nc(1)
53 main(int argc, char **argv)
55 struct sockaddr_in dst;
60 const char* sendbuf = "Hello, World!";
61 const size_t buflen = 80;
65 fprintf(stderr, "Usage: %s ip_address tapdev\n", argv[0]);
69 t = open(argv[2], O_RDWR | O_NONBLOCK);
71 err(EXIT_FAILURE, "open");
73 s = socket(PF_INET, SOCK_DGRAM, 0);
75 err(EXIT_FAILURE, "socket");
78 ret = setsockopt(s, SOL_SOCKET, SO_DONTROUTE, &opt, sizeof(opt));
80 err(EXIT_FAILURE, "setsockopt(SO_DONTROUTE)");
82 dst.sin_len = sizeof(dst);
83 dst.sin_family = AF_INET;
84 dst.sin_port = htons(46120);
85 dst.sin_addr.s_addr = inet_addr(argv[1]);
86 if (dst.sin_addr.s_addr == htonl(INADDR_NONE)) {
87 fprintf(stderr, "Invalid address: %s\n", argv[1]);
90 ret = sendto(s, sendbuf, strlen(sendbuf), 0, (struct sockaddr*)&dst,
93 err(EXIT_FAILURE, "sendto");
95 /* Verify that the packet went to the desired tap device */
97 len = read(t, recvbuf, buflen);
99 errx(EXIT_FAILURE, "read returned EOF");
100 else if (len < 0 && errno == EAGAIN)
101 errx(EXIT_FAILURE, "Did not receive any packets");
103 err(EXIT_FAILURE, "read");
106 * If read returned anything at all, consider it a success. The packet
107 * should be an Ethernet frame containing an ARP request for
108 * ip_address. We won't bother to decode it