usr/src/cmd/cmd-inet/usr.bin/telnet/network.c

   1 #pragma ident   "%Z%%M% %I%     %E% SMI"
   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. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  36  * Use is subject to license terms.
  37  */
  38
  39 #ifndef lint
  40 static char sccsid[] = "@(#)network.c   8.1 (Berkeley) 6/6/93";
  41 #endif /* not lint */
  42
  43 #include <sys/types.h>
  44 #include <sys/socket.h>
  45 #include <sys/time.h>
  46
  47 #include <errno.h>
  48
  49 #include <arpa/telnet.h>
  50
  51 #include "ring.h"
  52
  53 #include "defines.h"
  54 #include "externs.h"
  55
  56 Ring    netoring;
  57 Ring    netiring;
  58
  59 /*
  60  * Use large buffers to handle larger tickets when doing
  61  * Kerberos authentication.  Microsoft generates large
  62  * tickets that exceed the buffer size which causes authentication
  63  * to fail.
  64  */
  65 static unsigned char netobuf[10*BUFSIZ];
  66 static unsigned char netibuf[10*BUFSIZ];
  67
  68 /*
  69  * Initialize internal network data structures.
  70  */
  71
  72 void
  73 init_network()
  74 {
  75         if (ring_init(&netoring, netobuf, sizeof (netobuf)) != 1) {
  76                 exit(1);
  77         }
  78         if (ring_init(&netiring, netibuf, sizeof (netibuf)) != 1) {
  79                 exit(1);
  80         }
  81         NetTrace = stdout;
  82 }
  83
  84
  85 /*
  86  * Check to see if any out-of-band data exists on a socket (for
  87  * Telnet "synch" processing).
  88  */
  89
  90 int
  91 stilloob()
  92 {
  93         static struct timeval timeout = { 0 };
  94         fd_set  excepts;
  95         int value;
  96
  97         do {
  98                 FD_ZERO(&excepts);
  99                 FD_SET(net, &excepts);
 100                 value = select(net+1, NULL, NULL, &excepts, &timeout);
 101         } while ((value == -1) && (errno == EINTR));
 102
 103         if (value < 0) {
 104                 perror("select");
 105                 (void) quit();
 106                 /* NOTREACHED */
 107         }
 108         if (FD_ISSET(net, &excepts)) {
 109                 return (1);
 110         } else {
 111                 return (0);
 112         }
 113 }
 114
 115
 116 /*
 117  *  setneturg()
 118  *
 119  *      Sets "neturg" to the current location.
 120  */
 121
 122 void
 123 setneturg()
 124 {
 125         ring_mark(&netoring);
 126 }
 127
 128
 129 /*
 130  *  netflush
 131  *              Send as much data as possible to the network,
 132  *      handling requests for urgent data.
 133  *
 134  *              The return value indicates whether we did any
 135  *      useful work.
 136  */
 137
 138
 139 int
 140 netflush()
 141 {
 142         register int n, n1;
 143
 144         if (encrypt_output)
 145                 ring_encrypt(&netoring, encrypt_output);
 146
 147         if ((n1 = n = ring_full_consecutive(&netoring)) > 0) {
 148                 if (!ring_at_mark(&netoring)) {
 149                         /* normal write */
 150                         n = send(net, netoring.consume, n, 0);
 151                 } else {
 152                         /*
 153                          * In 4.2(and 4.3) systems, there is some question about
 154                          * what byte in a sendOOB operation is the "OOB" data.
 155                          * To make ourselves compatible, we only send ONE byte
 156                          * out of band, the one WE THINK should be OOB (though
 157                          * we really have more the TCP philosophy of urgent data
 158                          * rather than the Unix philosophy of OOB data).
 159                          */
 160                         n = send(net, netoring.consume, 1, MSG_OOB);
 161                 }
 162         }
 163         if (n < 0) {
 164                 if (errno != ENOBUFS && errno != EWOULDBLOCK) {
 165                         setcommandmode();
 166                         perror(hostname);
 167                         ring_clear_mark(&netoring);
 168                         longjmp(peerdied, -1);
 169                         /*NOTREACHED*/
 170                 }
 171                 n = 0;
 172         }
 173         if (netdata && n) {
 174                 Dump('>', netoring.consume, n);
 175         }
 176         if (n) {
 177                 ring_consumed(&netoring, n);
 178                 /*
 179                  * If we sent all, and more to send, then recurse to pick
 180                  * up the other half.
 181                  */
 182                 if ((n1 == n) && ring_full_consecutive(&netoring)) {
 183                         (void) netflush();
 184                 }
 185                 return (1);
 186         } else {
 187                 return (0);
 188         }
 189 }