xref: /illumos-gate/usr/src/lib/libnsl/nsl/t_rcvudata.c (revision 8b80e8cb6855118d46f605e91b5ed4ce83417395)
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 
23 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
24 /*	  All Rights Reserved  	*/
25 
26 /*
27  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SVr4.0 1.5 */
32 
33 /*
34  * t_rcvudata.c and t_rcvvudata.c are very similar and contain common code.
35  * Any changes to either of them should be reviewed to see whether they
36  * are applicable to the other file.
37  */
38 #include "mt.h"
39 #include <string.h>
40 #include <stdlib.h>
41 #include <errno.h>
42 #include <stropts.h>
43 #include <sys/stream.h>
44 #define	_SUN_TPI_VERSION 2
45 #include <sys/tihdr.h>
46 #include <sys/timod.h>
47 #include <xti.h>
48 #include <syslog.h>
49 #include "tx.h"
50 
51 
52 int
53 _tx_rcvudata(
54 	int fd,
55 	struct t_unitdata *unitdata,
56 	int *flags,
57 	int api_semantics
58 )
59 {
60 	struct strbuf ctlbuf;
61 	int retval;
62 	union T_primitives *pptr;
63 	struct _ti_user *tiptr;
64 	int sv_errno;
65 	int didalloc;
66 	int flg = 0;
67 
68 	if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL)
69 		return (-1);
70 	sig_mutex_lock(&tiptr->ti_lock);
71 
72 	if (tiptr->ti_servtype != T_CLTS) {
73 		t_errno = TNOTSUPPORT;
74 		sig_mutex_unlock(&tiptr->ti_lock);
75 		return (-1);
76 	}
77 
78 	if (_T_IS_XTI(api_semantics)) {
79 		/*
80 		 * User level state verification only done for XTI
81 		 * because doing for TLI may break existing applications
82 		 */
83 		if (tiptr->ti_state != T_IDLE) {
84 			t_errno = TOUTSTATE;
85 			sig_mutex_unlock(&tiptr->ti_lock);
86 			return (-1);
87 		}
88 	}
89 
90 
91 	/*
92 	 * check if there is something in look buffer
93 	 */
94 	if (tiptr->ti_lookcnt > 0) {
95 		sig_mutex_unlock(&tiptr->ti_lock);
96 		t_errno = TLOOK;
97 		return (-1);
98 	}
99 
100 	/*
101 	 * Acquire ctlbuf for use in sending/receiving control part
102 	 * of the message.
103 	 */
104 	if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) {
105 		sv_errno = errno;
106 		sig_mutex_unlock(&tiptr->ti_lock);
107 		errno = sv_errno;
108 		return (-1);
109 	}
110 
111 	*flags = 0;
112 
113 	/*
114 	 * This is a call that may block indefinitely so we drop the
115 	 * lock and allow signals in MT case here and reacquire it.
116 	 * Error case should roll back state changes done above
117 	 * (happens to be no state change here)
118 	 */
119 	sig_mutex_unlock(&tiptr->ti_lock);
120 	if ((retval = getmsg(fd, &ctlbuf, (struct strbuf *)&unitdata->udata,
121 				&flg)) < 0) {
122 		if (errno == EAGAIN)
123 			t_errno = TNODATA;
124 		else
125 			t_errno = TSYSERR;
126 		sv_errno = errno;
127 		sig_mutex_lock(&tiptr->ti_lock);
128 		errno = sv_errno;
129 		goto err_out;
130 	}
131 	sig_mutex_lock(&tiptr->ti_lock);
132 
133 	if (((struct strbuf *)&unitdata->udata)->len == -1)
134 		unitdata->udata.len = 0;
135 
136 	/*
137 	 * is there control piece with data?
138 	 */
139 	if (ctlbuf.len > 0) {
140 		if (ctlbuf.len < (int)sizeof (t_scalar_t)) {
141 			unitdata->udata.len = 0;
142 			t_errno = TSYSERR;
143 			errno = EPROTO;
144 			goto err_out;
145 		}
146 
147 		/* LINTED pointer cast */
148 		pptr = (union T_primitives *)ctlbuf.buf;
149 
150 		switch (pptr->type) {
151 
152 		case T_UNITDATA_IND:
153 			if ((ctlbuf.len <
154 			    (int)sizeof (struct T_unitdata_ind)) ||
155 			    (pptr->unitdata_ind.OPT_length &&
156 			    (ctlbuf.len < (int)(pptr->unitdata_ind.OPT_length
157 			    + pptr->unitdata_ind.OPT_offset)))) {
158 				t_errno = TSYSERR;
159 				unitdata->udata.len = 0;
160 				errno = EPROTO;
161 				goto err_out;
162 			}
163 
164 			if (_T_IS_TLI(api_semantics) ||
165 			    unitdata->addr.maxlen > 0) {
166 				if (TLEN_GT_NLEN(pptr->unitdata_ind.SRC_length,
167 				    unitdata->addr.maxlen)) {
168 					t_errno = TBUFOVFLW;
169 					unitdata->udata.len = 0;
170 					goto err_out;
171 				}
172 				(void) memcpy(unitdata->addr.buf,
173 				    ctlbuf.buf + pptr->unitdata_ind.SRC_offset,
174 				    (size_t)pptr->unitdata_ind.SRC_length);
175 				unitdata->addr.len =
176 				    pptr->unitdata_ind.SRC_length;
177 			}
178 			if (_T_IS_TLI(api_semantics) ||
179 			    unitdata->opt.maxlen > 0) {
180 				if (TLEN_GT_NLEN(pptr->unitdata_ind.OPT_length,
181 				    unitdata->opt.maxlen)) {
182 					t_errno = TBUFOVFLW;
183 					unitdata->udata.len = 0;
184 					goto err_out;
185 				}
186 				(void) memcpy(unitdata->opt.buf, ctlbuf.buf +
187 				    pptr->unitdata_ind.OPT_offset,
188 				    (size_t)pptr->unitdata_ind.OPT_length);
189 				unitdata->opt.len =
190 					pptr->unitdata_ind.OPT_length;
191 			}
192 			if (retval & MOREDATA)
193 				*flags |= T_MORE;
194 			/*
195 			 * No state changes happens on T_RCVUDATA
196 			 * event (NOOP). We do it only to log errors.
197 			 */
198 			_T_TX_NEXTSTATE(T_RCVUDATA, tiptr,
199 			    "t_rcvudata: invalid state event T_RCVUDATA");
200 
201 			if (didalloc)
202 				free(ctlbuf.buf);
203 			else
204 				tiptr->ti_ctlbuf = ctlbuf.buf;
205 
206 			sig_mutex_unlock(&tiptr->ti_lock);
207 			return (0);
208 
209 		case T_UDERROR_IND:
210 			if (_t_register_lookevent(tiptr, 0, 0, ctlbuf.buf,
211 				ctlbuf.len) < 0) {
212 				t_errno = TSYSERR;
213 				errno = ENOMEM;
214 				goto err_out;
215 			}
216 			unitdata->udata.len = 0;
217 			t_errno = TLOOK;
218 			goto err_out;
219 
220 		default:
221 			break;
222 		}
223 
224 		t_errno = TSYSERR;
225 		errno = EPROTO;
226 		goto err_out;
227 
228 	} else {		/* else part of "if (ctlbuf.len > 0)" */
229 		unitdata->addr.len = 0;
230 		unitdata->opt.len = 0;
231 		/*
232 		 * only data in message no control piece
233 		 */
234 		if (retval & MOREDATA)
235 			*flags = T_MORE;
236 		/*
237 		 * No state transition occurs on
238 		 * event T_RCVUDATA. We do it only to
239 		 * log errors.
240 		 */
241 		_T_TX_NEXTSTATE(T_RCVUDATA, tiptr,
242 		    "t_rcvudata: invalid state event T_RCVUDATA");
243 		if (didalloc)
244 			free(ctlbuf.buf);
245 		else
246 			tiptr->ti_ctlbuf = ctlbuf.buf;
247 		sig_mutex_unlock(&tiptr->ti_lock);
248 		return (0);
249 	}
250 	/* NOTREACHED */
251 err_out:
252 	sv_errno = errno;
253 	if (didalloc)
254 		free(ctlbuf.buf);
255 	else
256 		tiptr->ti_ctlbuf = ctlbuf.buf;
257 	sig_mutex_unlock(&tiptr->ti_lock);
258 	errno = sv_errno;
259 	return (-1);
260 }
261