1 /* $NetBSD: network.c,v 1.17 2004/03/20 23:26:05 heas Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)network.c 8.2 (Berkeley) 12/15/93"; 36 #else 37 __RCSID("$NetBSD: network.c,v 1.17 2004/03/20 23:26:05 heas Exp $"); 38 #endif 39 #endif /* not lint */ 40 41 #include <sys/types.h> 42 #include <sys/socket.h> 43 #include <sys/time.h> 44 45 #include <errno.h> 46 #include <unistd.h> 47 #include <poll.h> 48 49 #include <arpa/telnet.h> 50 51 #include "ring.h" 52 #include "defines.h" 53 #include "externs.h" 54 55 Ring netoring, netiring; 56 unsigned char netobuf[2*BUFSIZ], netibuf[BUFSIZ]; 57 58 /* 59 * Initialize internal network data structures. 60 */ 61 62 void 63 init_network(void) 64 { 65 if (ring_init(&netoring, netobuf, sizeof netobuf) != 1) { 66 exit(1); 67 } 68 if (ring_init(&netiring, netibuf, sizeof netibuf) != 1) { 69 exit(1); 70 } 71 NetTrace = stdout; 72 } 73 74 75 /* 76 * Check to see if any out-of-band data exists on a socket (for 77 * Telnet "synch" processing). 78 */ 79 80 int 81 stilloob(void) 82 { 83 struct pollfd set[1]; 84 int value; 85 86 set[0].fd = net; 87 set[0].events = POLLPRI; 88 do { 89 value = poll(set, 1, 0); 90 } while ((value == -1) && (errno == EINTR)); 91 92 if (value < 0) { 93 perror("poll"); 94 (void) quit(0, NULL); 95 /* NOTREACHED */ 96 } 97 if (set[0].revents & POLLPRI) { 98 return 1; 99 } else { 100 return 0; 101 } 102 } 103 104 105 /* 106 * setneturg() 107 * 108 * Sets "neturg" to the current location. 109 */ 110 111 void 112 setneturg(void) 113 { 114 ring_mark(&netoring); 115 } 116 117 118 /* 119 * netflush 120 * Send as much data as possible to the network, 121 * handling requests for urgent data. 122 * 123 * The return value indicates whether we did any 124 * useful work. 125 */ 126 127 128 int 129 netflush(void) 130 { 131 int n, n1; 132 133 #ifdef ENCRYPTION 134 if (encrypt_output) 135 ring_encrypt(&netoring, encrypt_output); 136 #endif /* ENCRYPTION */ 137 if ((n1 = n = ring_full_consecutive(&netoring)) > 0) { 138 if (!ring_at_mark(&netoring)) { 139 n = send(net, (char *)netoring.consume, n, 0); /* normal write */ 140 } else { 141 /* 142 * In 4.2 (and 4.3) systems, there is some question about 143 * what byte in a sendOOB operation is the "OOB" data. 144 * To make ourselves compatible, we only send ONE byte 145 * out of band, the one WE THINK should be OOB (though 146 * we really have more the TCP philosophy of urgent data 147 * rather than the Unix philosophy of OOB data). 148 */ 149 n = send(net, (char *)netoring.consume, 1, MSG_OOB);/* URGENT data */ 150 } 151 } 152 if (n < 0) { 153 if (errno != ENOBUFS && errno != EWOULDBLOCK) { 154 setcommandmode(); 155 perror(hostname); 156 (void)NetClose(net); 157 ring_clear_mark(&netoring); 158 ExitString("Connection closed by foreign host.\n", 1); 159 /*NOTREACHED*/ 160 } 161 n = 0; 162 } 163 if (netdata && n) { 164 Dump('>', netoring.consume, n); 165 } 166 if (n) { 167 ring_consumed(&netoring, n); 168 /* 169 * If we sent all, and more to send, then recurse to pick 170 * up the other half. 171 */ 172 if ((n1 == n) && ring_full_consecutive(&netoring)) { 173 (void) netflush(); 174 } 175 return 1; 176 } else { 177 return 0; 178 } 179 } 180