1 /* 2 * Copyright (c) 1988, 1993 3 * The Regents of the University of California. 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 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)network.c 8.2 (Berkeley) 12/15/93 30 * $FreeBSD: src/crypto/telnet/telnet/network.c,v 1.2.8.2 2002/04/13 10:59:08 markm Exp $ 31 * $DragonFly: src/crypto/telnet/telnet/network.c,v 1.2 2003/06/17 04:24:37 dillon Exp $ 32 */ 33 34 #include <sys/types.h> 35 #include <sys/socket.h> 36 #include <sys/time.h> 37 38 #include <errno.h> 39 40 #include <arpa/telnet.h> 41 #include <stdlib.h> 42 #include <unistd.h> 43 44 #include "ring.h" 45 46 #include "defines.h" 47 #include "externs.h" 48 #include "fdset.h" 49 50 Ring netoring, netiring; 51 unsigned char netobuf[2*BUFSIZ], netibuf[BUFSIZ]; 52 53 /* 54 * Initialize internal network data structures. 55 */ 56 57 void 58 init_network(void) 59 { 60 if (ring_init(&netoring, netobuf, sizeof netobuf) != 1) { 61 exit(1); 62 } 63 if (ring_init(&netiring, netibuf, sizeof netibuf) != 1) { 64 exit(1); 65 } 66 NetTrace = stdout; 67 } 68 69 70 /* 71 * Check to see if any out-of-band data exists on a socket (for 72 * Telnet "synch" processing). 73 */ 74 75 int 76 stilloob(void) 77 { 78 static struct timeval timeout = { 0, 0 }; 79 fd_set excepts; 80 int value; 81 82 do { 83 FD_ZERO(&excepts); 84 FD_SET(net, &excepts); 85 value = select(net+1, NULL, NULL, &excepts, &timeout); 86 } while ((value == -1) && (errno == EINTR)); 87 88 if (value < 0) { 89 perror("select"); 90 (void) quit(); 91 /* NOTREACHED */ 92 } 93 if (FD_ISSET(net, &excepts)) { 94 return 1; 95 } else { 96 return 0; 97 } 98 } 99 100 101 /* 102 * setneturg() 103 * 104 * Sets "neturg" to the current location. 105 */ 106 107 void 108 setneturg(void) 109 { 110 ring_mark(&netoring); 111 } 112 113 114 /* 115 * netflush 116 * Send as much data as possible to the network, 117 * handling requests for urgent data. 118 * 119 * The return value indicates whether we did any 120 * useful work. 121 */ 122 123 int 124 netflush(void) 125 { 126 int n, n1; 127 128 #ifdef ENCRYPTION 129 if (encrypt_output) 130 ring_encrypt(&netoring, encrypt_output); 131 #endif /* ENCRYPTION */ 132 if ((n1 = n = ring_full_consecutive(&netoring)) > 0) { 133 if (!ring_at_mark(&netoring)) { 134 n = send(net, (char *)netoring.consume, n, 0); /* normal write */ 135 } else { 136 /* 137 * In 4.2 (and 4.3) systems, there is some question about 138 * what byte in a sendOOB operation is the "OOB" data. 139 * To make ourselves compatible, we only send ONE byte 140 * out of band, the one WE THINK should be OOB (though 141 * we really have more the TCP philosophy of urgent data 142 * rather than the Unix philosophy of OOB data). 143 */ 144 n = send(net, (char *)netoring.consume, 1, MSG_OOB);/* URGENT data */ 145 } 146 } 147 if (n < 0) { 148 if (errno != ENOBUFS && errno != EWOULDBLOCK) { 149 setcommandmode(); 150 perror(hostname); 151 (void)NetClose(net); 152 ring_clear_mark(&netoring); 153 longjmp(peerdied, -1); 154 /*NOTREACHED*/ 155 } 156 n = 0; 157 } 158 if (netdata && n) { 159 Dump('>', netoring.consume, n); 160 } 161 if (n) { 162 ring_consumed(&netoring, n); 163 /* 164 * If we sent all, and more to send, then recurse to pick 165 * up the other half. 166 */ 167 if ((n1 == n) && ring_full_consecutive(&netoring)) { 168 (void) netflush(); 169 } 170 return 1; 171 } else { 172 return 0; 173 } 174 } 175