1 /*- 2 * Copyright (c) 2006, Andrea Bittau <a.bittau@cs.ucl.ac.uk> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: src/tools/tools/net80211/w00t/redir/buddy.c,v 1.1 2006/08/05 05:18:03 sam Exp $ 27 */ 28 #include <sys/uio.h> 29 #include <sys/types.h> 30 #include <sys/socket.h> 31 #include <netinet/in_systm.h> 32 #include <netinet/in.h> 33 #include <arpa/inet.h> 34 #include <netinet/ip.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #include <unistd.h> 39 #include <fcntl.h> 40 #include <errno.h> 41 #include <signal.h> 42 #include <err.h> 43 44 void hexdump(void *b, int len) 45 { 46 unsigned char *p = (unsigned char*) b; 47 48 while (len--) 49 printf("%.2X ", *p++); 50 printf("\n"); 51 } 52 53 int handle_data(int dude, char *buf, int len) 54 { 55 struct ip *ih; 56 unsigned short id; 57 char tmp[4]; 58 struct iovec iov[2]; 59 struct msghdr mh; 60 61 ih = (struct ip*) buf; 62 63 /* XXX IP FRAGS */ 64 65 /* filter */ 66 if (ih->ip_p != 0) 67 return 0; 68 69 if (ih->ip_hl != 5) 70 return 0; 71 72 /* get info */ 73 id = ih->ip_id; 74 len -= 20; 75 buf += 20; 76 printf("Got %d bytes [%d]\n", len, ntohs(id)); 77 #if 0 78 hexdump(buf, len); 79 #endif 80 81 /* prepare packet */ 82 memcpy(tmp, &id, 2); 83 id = htons(len); 84 memcpy(&tmp[2], &id, 2); 85 86 iov[0].iov_base = tmp; 87 iov[0].iov_len = 4; 88 iov[1].iov_base = buf; 89 iov[1].iov_len = len; 90 91 memset(&mh, 0, sizeof(mh)); 92 mh.msg_iov = iov; 93 mh.msg_iovlen = sizeof(iov)/sizeof(struct iovec); 94 95 /* write */ 96 if (sendmsg(dude, &mh, 0) != (4 + len)) 97 return -1; 98 return 0; 99 } 100 101 void handle_dude(int dude, int raw) 102 { 103 char buf[4096]; 104 int rd; 105 106 while (1) { 107 rd = recv(raw, buf, sizeof(buf), 0); 108 if (rd == -1) 109 err(1, "recv()"); 110 111 if (handle_data(dude, buf, rd) == -1) 112 return; 113 } 114 } 115 116 void hand(int s) 117 { 118 printf("sigpipe\n"); 119 } 120 121 int main(int argc, char *argv[]) 122 { 123 int s, dude; 124 struct sockaddr_in s_in; 125 int len; 126 int raw; 127 128 memset(&s_in, 0, sizeof(s_in)); 129 s_in.sin_family = PF_INET; 130 s_in.sin_port = htons(666); 131 s_in.sin_addr.s_addr = INADDR_ANY; 132 133 if ((raw = socket(PF_INET, SOCK_RAW, 0)) == -1) 134 err(1, "socket()"); 135 136 if ((s = socket(s_in.sin_family, SOCK_STREAM, IPPROTO_TCP)) == -1) 137 err(1, "socket()"); 138 139 if (bind(s, (struct sockaddr*)&s_in, sizeof(s_in)) == -1) 140 err(1, "bind()"); 141 142 if (listen(s, 5) == -1) 143 err(1, "listen()"); 144 145 if (signal(SIGPIPE, hand) == SIG_ERR) 146 err(1, "signal()"); 147 148 while (1) { 149 len = sizeof(s_in); 150 dude = accept(s, (struct sockaddr*)&s_in, &len); 151 if (dude == -1) 152 err(1, "accept()"); 153 154 printf("Got dude %s\n", inet_ntoa(s_in.sin_addr)); 155 handle_dude(dude, raw); 156 printf("Done\n"); 157 } 158 } 159