1 /* $OpenBSD: network.c,v 1.8 2003/06/03 02:56:18 millert Exp $ */ 2 /* $NetBSD: network.c,v 1.5 1996/02/28 21:04:06 thorpej Exp $ */ 3 4 /* 5 * Copyright (c) 1988, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include "telnet_locl.h" 34 #include <err.h> 35 36 Ring netoring, netiring; 37 unsigned char netobuf[2*BUFSIZ], netibuf[BUFSIZ]; 38 39 /* 40 * Initialize internal network data structures. 41 */ 42 43 void 44 init_network() 45 { 46 if (ring_init(&netoring, netobuf, sizeof netobuf) != 1) { 47 exit(1); 48 } 49 if (ring_init(&netiring, netibuf, sizeof netibuf) != 1) { 50 exit(1); 51 } 52 NetTrace = stdout; 53 } 54 55 56 /* 57 * Check to see if any out-of-band data exists on a socket (for 58 * Telnet "synch" processing). 59 */ 60 61 int 62 stilloob() 63 { 64 static struct timeval timeout = { 0 }; 65 fd_set *fdsp; 66 int fdsn; 67 int value; 68 69 fdsn = howmany(net+1, NFDBITS) * sizeof(fd_mask); 70 if ((fdsp = (fd_set *)malloc(fdsn)) == NULL) 71 err(1, "malloc"); 72 73 do { 74 memset(fdsp, 0, fdsn); 75 FD_SET(net, fdsp); 76 value = select(net+1, (fd_set *)0, (fd_set *)0, fdsp, &timeout); 77 } while ((value == -1) && (errno == EINTR)); 78 79 if (value < 0) { 80 perror("select"); 81 free(fdsp); 82 (void) quit(); 83 /* NOTREACHED */ 84 } 85 if (FD_ISSET(net, fdsp)) { 86 free(fdsp); 87 return 1; 88 } else { 89 free(fdsp); 90 return 0; 91 } 92 } 93 94 95 /* 96 * setneturg() 97 * 98 * Sets "neturg" to the current location. 99 */ 100 101 void 102 setneturg() 103 { 104 ring_mark(&netoring); 105 } 106 107 108 /* 109 * netflush 110 * Send as much data as possible to the network, 111 * handling requests for urgent data. 112 * 113 * The return value indicates whether we did any 114 * useful work. 115 */ 116 117 118 int 119 netflush() 120 { 121 int n, n1; 122 123 #if defined(ENCRYPTION) 124 if (encrypt_output) 125 ring_encrypt(&netoring, encrypt_output); 126 #endif 127 if ((n1 = n = ring_full_consecutive(&netoring)) > 0) { 128 if (!ring_at_mark(&netoring)) { 129 n = send(net, (char *)netoring.consume, n, 0); /* normal write */ 130 } else { 131 /* 132 * In 4.2 (and 4.3) systems, there is some question about 133 * what byte in a sendOOB operation is the "OOB" data. 134 * To make ourselves compatible, we only send ONE byte 135 * out of band, the one WE THINK should be OOB (though 136 * we really have more the TCP philosophy of urgent data 137 * rather than the Unix philosophy of OOB data). 138 */ 139 n = send(net, (char *)netoring.consume, 1, MSG_OOB);/* URGENT data */ 140 } 141 } 142 if (n < 0) { 143 if (errno != ENOBUFS && errno != EWOULDBLOCK) { 144 setcommandmode(); 145 perror(hostname); 146 (void)NetClose(net); 147 ring_clear_mark(&netoring); 148 longjmp(peerdied, -1); 149 /*NOTREACHED*/ 150 } 151 n = 0; 152 } 153 if (netdata && n) { 154 Dump('>', netoring.consume, n); 155 } 156 if (n) { 157 ring_consumed(&netoring, n); 158 /* 159 * If we sent all, and more to send, then recurse to pick 160 * up the other half. 161 */ 162 if ((n1 == n) && ring_full_consecutive(&netoring)) { 163 (void) netflush(); 164 } 165 return 1; 166 } else { 167 return 0; 168 } 169 } 170