xref: /illumos-gate/usr/src/lib/libnsl/nsl/t_rcvdis.c (revision 7c478bd9)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 
26 /*
27  * Copyright 1993-2003 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 
32 #pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SVr4.0 1.10 */
33 
34 #include "mt.h"
35 #include <rpc/trace.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <errno.h>
39 #include <stropts.h>
40 #include <sys/stream.h>
41 #define	_SUN_TPI_VERSION 2
42 #include <sys/tihdr.h>
43 #include <sys/timod.h>
44 #include <xti.h>
45 #include <signal.h>
46 #include <syslog.h>
47 #include "tx.h"
48 
49 int
50 _tx_rcvdis(int fd, struct t_discon *discon, int api_semantics)
51 {
52 	struct strbuf ctlbuf;
53 	struct strbuf databuf;
54 	int retval;
55 	union T_primitives *pptr;
56 	struct _ti_user *tiptr;
57 	int sv_errno;
58 	int flg = 0;
59 	int didalloc, didralloc;
60 	int use_lookbufs = 0;
61 
62 	trace2(TR_t_rcvdis, 0, fd);
63 	if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL) {
64 		sv_errno = errno;
65 		trace2(TR_t_rcvdis, 1, fd);
66 		errno = sv_errno;
67 		return (-1);
68 	}
69 
70 	/*
71 	 * Acquire per thread lock.
72 	 * Note: Lock is held across most of this routine
73 	 * including the blocking getmsg() call. This is fine
74 	 * because it is first verfied that an event is pending
75 	 */
76 	sig_mutex_lock(&tiptr->ti_lock);
77 
78 	if (tiptr->ti_servtype == T_CLTS) {
79 		t_errno = TNOTSUPPORT;
80 		sig_mutex_unlock(&tiptr->ti_lock);
81 		trace2(TR_t_rcvdis, 1, fd);
82 		return (-1);
83 	}
84 
85 	if (_T_IS_XTI(api_semantics)) {
86 		/*
87 		 * User level state verification only done for XTI
88 		 * because doing for TLI may break existing applications
89 		 */
90 		if (! (tiptr->ti_state == T_DATAXFER ||
91 		    tiptr->ti_state == T_OUTCON ||
92 		    tiptr->ti_state == T_OUTREL ||
93 		    tiptr->ti_state == T_INREL ||
94 		    (tiptr->ti_state == T_INCON && tiptr->ti_ocnt > 0))) {
95 			t_errno = TOUTSTATE;
96 			sig_mutex_unlock(&tiptr->ti_lock);
97 			trace2(TR_t_rcvdis, 1, fd);
98 			return (-1);
99 		}
100 	}
101 	/*
102 	 * Handle likely scenario as special case:
103 	 * Is there a discon in look buffer as the first
104 	 * event in the lookbuffer, is so just get it.
105 	 */
106 	if ((tiptr->ti_lookcnt > 0) &&
107 	    (*((t_scalar_t *)tiptr->ti_lookbufs.tl_lookcbuf) == T_DISCON_IND)) {
108 		/*
109 		 * The T_DISCON_IND is already in the look buffer
110 		 */
111 		ctlbuf.len = tiptr->ti_lookbufs.tl_lookclen;
112 		ctlbuf.buf = tiptr->ti_lookbufs.tl_lookcbuf;
113 		/* Note: ctlbuf.maxlen not used in this case */
114 
115 		databuf.len = tiptr->ti_lookbufs.tl_lookdlen;
116 		databuf.buf = tiptr->ti_lookbufs.tl_lookdbuf;
117 		/* Note databuf.maxlen not used in this case */
118 
119 		use_lookbufs = 1;
120 
121 	} else {
122 
123 		if ((retval = _t_look_locked(fd, tiptr, 0,
124 		    api_semantics)) < 0) {
125 			sv_errno = errno;
126 			sig_mutex_unlock(&tiptr->ti_lock);
127 			trace2(TR_t_rcvdis, 1, fd);
128 			errno = sv_errno;
129 			return (-1);
130 		}
131 
132 		if (retval != T_DISCONNECT) {
133 			t_errno = TNODIS;
134 			sig_mutex_unlock(&tiptr->ti_lock);
135 			trace2(TR_t_rcvdis, 1, fd);
136 			return (-1);
137 		}
138 
139 		/*
140 		 * get disconnect off read queue.
141 		 * use ctl and rcv buffers
142 		 *
143 		 * Acquire ctlbuf for use in sending/receiving control part
144 		 * of the message.
145 		 */
146 		if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) {
147 			sv_errno = errno;
148 			sig_mutex_unlock(&tiptr->ti_lock);
149 			trace2(TR_t_rcvdis, 1, fd);
150 			errno = sv_errno;
151 			return (-1);
152 		}
153 
154 		/*
155 		 * Acquire databuf for use in sending/receiving data part
156 		 */
157 		if (_t_acquire_databuf(tiptr, &databuf, &didralloc) < 0) {
158 			sv_errno = errno;
159 			if (didalloc)
160 				free(ctlbuf.buf);
161 			else
162 				tiptr->ti_ctlbuf = ctlbuf.buf;
163 			sig_mutex_unlock(&tiptr->ti_lock);
164 			trace2(TR_t_rcvdis, 1, fd);
165 			errno = sv_errno;
166 			return (-1);
167 		}
168 
169 		/*
170 		 * Since we already verified that a disconnect event
171 		 * is present, we assume that this getmsg() cannot
172 		 * block indefinitely
173 		 */
174 		do {
175 			retval = getmsg(fd, &ctlbuf, &databuf, &flg);
176 		} while (retval < 0 && errno == EINTR);
177 
178 		if (retval  < 0) {
179 			t_errno = TSYSERR;
180 			goto err_out;
181 		}
182 		if (databuf.len == -1) databuf.len = 0;
183 
184 		/*
185 		 * did I get entire message?
186 		 */
187 		if (retval > 0) {
188 			t_errno = TSYSERR;
189 			errno = EIO;
190 			goto err_out;
191 		}
192 	}
193 
194 
195 	pptr = (union T_primitives *)ctlbuf.buf;
196 
197 	if ((ctlbuf.len < (int)sizeof (struct T_discon_ind)) ||
198 	    (pptr->type != T_DISCON_IND)) {
199 		t_errno = TSYSERR;
200 		errno = EPROTO;
201 		goto err_out;
202 	}
203 
204 	/*
205 	 * clear more and expedited flags
206 	 */
207 	tiptr->ti_flags &= ~(MORE | EXPEDITED);
208 
209 	if (tiptr->ti_ocnt <= 0) {
210 		_T_TX_NEXTSTATE(T_RCVDIS1, tiptr,
211 				"t_rcvdis: invalid state event T_RCVDIS1");
212 	} else {
213 		if (tiptr->ti_ocnt == 1) {
214 			_T_TX_NEXTSTATE(T_RCVDIS2, tiptr,
215 				"t_rcvdis: invalid state event T_RCVDIS2");
216 		} else {
217 			_T_TX_NEXTSTATE(T_RCVDIS3, tiptr,
218 				"t_rcvdis: invalid state event T_RCVDIS3");
219 		}
220 		tiptr->ti_ocnt--;
221 		tiptr->ti_flags &= ~TX_TQFULL_NOTIFIED;
222 	}
223 
224 	if (discon != NULL) {
225 		if (_T_IS_TLI(api_semantics) || discon->udata.maxlen > 0) {
226 			if (databuf.len > (int)discon->udata.maxlen) {
227 				t_errno = TBUFOVFLW;
228 				goto err_out;
229 			}
230 			(void) memcpy(discon->udata.buf, databuf.buf,
231 			    (size_t)databuf.len);
232 			discon->udata.len = databuf.len;
233 		}
234 		discon->reason = pptr->discon_ind.DISCON_reason;
235 		discon->sequence = pptr->discon_ind.SEQ_number;
236 	}
237 	if (use_lookbufs)
238 		_t_free_looklist_head(tiptr);
239 	else {
240 		if (didalloc)
241 			free(ctlbuf.buf);
242 		else
243 			tiptr->ti_ctlbuf = ctlbuf.buf;
244 		if (didralloc)
245 			free(databuf.buf);
246 		else
247 			tiptr->ti_rcvbuf = databuf.buf;
248 	}
249 	sig_mutex_unlock(&tiptr->ti_lock);
250 	trace2(TR_t_rcvdis, 1, fd);
251 	return (0);
252 
253 err_out:
254 	sv_errno = errno;
255 
256 	if (use_lookbufs)
257 		_t_free_looklist_head(tiptr);
258 	else {
259 		if (didalloc)
260 			free(ctlbuf.buf);
261 		else
262 			tiptr->ti_ctlbuf = ctlbuf.buf;
263 		if (didralloc)
264 			free(databuf.buf);
265 		else
266 			tiptr->ti_rcvbuf = databuf.buf;
267 	}
268 	sig_mutex_unlock(&tiptr->ti_lock);
269 	trace2(TR_t_rcvdis, 1, fd);
270 	errno = sv_errno;
271 	return (-1);
272 }
273