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 */ 32 33 #include <sys/types.h> 34 #include <sys/socket.h> 35 #include <sys/time.h> 36 37 #include <errno.h> 38 39 #include <arpa/telnet.h> 40 #include <stdlib.h> 41 #include <unistd.h> 42 43 #include "ring.h" 44 45 #include "defines.h" 46 #include "externs.h" 47 #include "fdset.h" 48 49 Ring netoring, netiring; 50 unsigned char netobuf[2*BUFSIZ], netibuf[BUFSIZ]; 51 52 /* 53 * Initialize internal network data structures. 54 */ 55 56 void 57 init_network(void) 58 { 59 if (ring_init(&netoring, netobuf, sizeof netobuf) != 1) { 60 exit(1); 61 } 62 if (ring_init(&netiring, netibuf, sizeof netibuf) != 1) { 63 exit(1); 64 } 65 NetTrace = stdout; 66 } 67 68 69 /* 70 * Check to see if any out-of-band data exists on a socket (for 71 * Telnet "synch" processing). 72 */ 73 74 int 75 stilloob(void) 76 { 77 static struct timeval timeout = { 0, 0 }; 78 fd_set excepts; 79 int value; 80 81 do { 82 FD_ZERO(&excepts); 83 FD_SET(net, &excepts); 84 value = select(net+1, NULL, NULL, &excepts, &timeout); 85 } while ((value == -1) && (errno == EINTR)); 86 87 if (value < 0) { 88 perror("select"); 89 (void) quit(); 90 /* NOTREACHED */ 91 } 92 if (FD_ISSET(net, &excepts)) { 93 return 1; 94 } else { 95 return 0; 96 } 97 } 98 99 100 /* 101 * setneturg() 102 * 103 * Sets "neturg" to the current location. 104 */ 105 106 void 107 setneturg(void) 108 { 109 ring_mark(&netoring); 110 } 111 112 113 /* 114 * netflush 115 * Send as much data as possible to the network, 116 * handling requests for urgent data. 117 * 118 * The return value indicates whether we did any 119 * useful work. 120 */ 121 122 int 123 netflush(void) 124 { 125 int n, n1; 126 127 #ifdef ENCRYPTION 128 if (encrypt_output) 129 ring_encrypt(&netoring, encrypt_output); 130 #endif /* ENCRYPTION */ 131 if ((n1 = n = ring_full_consecutive(&netoring)) > 0) { 132 if (!ring_at_mark(&netoring)) { 133 n = send(net, (char *)netoring.consume, n, 0); /* normal write */ 134 } else { 135 /* 136 * In 4.2 (and 4.3) systems, there is some question about 137 * what byte in a sendOOB operation is the "OOB" data. 138 * To make ourselves compatible, we only send ONE byte 139 * out of band, the one WE THINK should be OOB (though 140 * we really have more the TCP philosophy of urgent data 141 * rather than the Unix philosophy of OOB data). 142 */ 143 n = send(net, (char *)netoring.consume, 1, MSG_OOB);/* URGENT data */ 144 } 145 } 146 if (n < 0) { 147 if (errno != ENOBUFS && errno != EWOULDBLOCK) { 148 setcommandmode(); 149 perror(hostname); 150 (void)NetClose(net); 151 ring_clear_mark(&netoring); 152 longjmp(peerdied, -1); 153 /*NOTREACHED*/ 154 } 155 n = 0; 156 } 157 if (netdata && n) { 158 Dump('>', netoring.consume, n); 159 } 160 if (n) { 161 ring_consumed(&netoring, n); 162 /* 163 * If we sent all, and more to send, then recurse to pick 164 * up the other half. 165 */ 166 if ((n1 == n) && ring_full_consecutive(&netoring)) { 167 (void) netflush(); 168 } 169 return 1; 170 } else { 171 return 0; 172 } 173 } 174