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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "telnet_locl.h" 35 36 RCSID("$Id$"); 37 38 Ring netoring, netiring; 39 size_t netobufsize = 64*1024; 40 size_t netibufsize = 64*1024; 41 42 /* 43 * Initialize internal network data structures. 44 */ 45 46 void 47 init_network(void) 48 { 49 void *obuf, *ibuf; 50 51 if ((obuf = malloc(netobufsize)) == NULL) 52 exit(1); 53 if ((ibuf = malloc(netibufsize)) == NULL) 54 exit(1); 55 56 if (ring_init(&netoring, obuf, netobufsize) != 1) { 57 exit(1); 58 } 59 if (ring_init(&netiring, ibuf, netibufsize) != 1) { 60 exit(1); 61 } 62 NetTrace = stdout; 63 } 64 65 66 /* 67 * Check to see if any out-of-band data exists on a socket (for 68 * Telnet "synch" processing). 69 */ 70 71 int 72 stilloob(void) 73 { 74 static struct timeval timeout = { 0 }; 75 fd_set excepts; 76 int value; 77 78 do { 79 FD_ZERO(&excepts); 80 if (net >= FD_SETSIZE) 81 errx (1, "fd too large"); 82 FD_SET(net, &excepts); 83 value = select(net+1, 0, 0, &excepts, &timeout); 84 } while ((value == -1) && (errno == EINTR)); 85 86 if (value < 0) { 87 perror("select"); 88 quit(); 89 /* NOTREACHED */ 90 } 91 if (FD_ISSET(net, &excepts)) { 92 return 1; 93 } else { 94 return 0; 95 } 96 } 97 98 99 /* 100 * setneturg() 101 * 102 * Sets "neturg" to the current location. 103 */ 104 105 void 106 setneturg(void) 107 { 108 ring_mark(&netoring); 109 } 110 111 112 /* 113 * netflush 114 * Send as much data as possible to the network, 115 * handling requests for urgent data. 116 * 117 * The return value indicates whether we did any 118 * useful work. 119 */ 120 121 122 int 123 netflush(void) 124 { 125 int n, n1; 126 127 #if defined(ENCRYPTION) 128 if (encrypt_output) 129 ring_encrypt(&netoring, encrypt_output); 130 #endif 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 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 netflush(); 168 } 169 return 1; 170 } else { 171 return 0; 172 } 173 } 174