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
init_network()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
stilloob()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
setneturg()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
netflush()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 }
190