xref: /illumos-gate/usr/src/lib/libnsl/nsl/t_rcvvudata.c (revision 1f5207b7604fb44407eb4342aff613f7c4508508)
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 /*
24  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 /*
31  * t_rcvudata.c and t_rcvvudata.c are very similar and contain common code.
32  * Any changes to either of them should be reviewed to see whether they
33  * are applicable to the other file.
34  */
35 #include "mt.h"
36 #include <string.h>
37 #include <stdlib.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 <syslog.h>
46 #include <assert.h>
47 #include "tx.h"
48 
49 
50 int
51 _tx_rcvvudata(
52 	int fd,
53 	struct t_unitdata *unitdata,
54 	struct t_iovec *tiov,
55 	unsigned int tiovcount,
56 	int *flags,
57 	int api_semantics
58 )
59 {
60 	struct strbuf ctlbuf;
61 	struct strbuf databuf;
62 	char *dataptr;
63 	int retval;
64 	union T_primitives *pptr;
65 	struct _ti_user *tiptr;
66 	int sv_errno;
67 	int didalloc;
68 	int flg = 0;
69 	unsigned int nbytes;
70 
71 	assert(api_semantics == TX_XTI_XNS5_API);
72 
73 	if (tiovcount == 0 || tiovcount > T_IOV_MAX) {
74 		t_errno = TBADDATA;
75 		return (-1);
76 	}
77 
78 	if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL)
79 		return (-1);
80 	sig_mutex_lock(&tiptr->ti_lock);
81 
82 	if (tiptr->ti_servtype != T_CLTS) {
83 		t_errno = TNOTSUPPORT;
84 		sig_mutex_unlock(&tiptr->ti_lock);
85 		return (-1);
86 	}
87 
88 	if (tiptr->ti_state != T_IDLE) {
89 		t_errno = TOUTSTATE;
90 		sig_mutex_unlock(&tiptr->ti_lock);
91 		return (-1);
92 	}
93 
94 	/*
95 	 * check if there is something in look buffer
96 	 */
97 	if (tiptr->ti_lookcnt > 0) {
98 		sig_mutex_unlock(&tiptr->ti_lock);
99 		t_errno = TLOOK;
100 		return (-1);
101 	}
102 
103 	/*
104 	 * Acquire ctlbuf for use in sending/receiving control part
105 	 * of the message.
106 	 */
107 	if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) {
108 		sv_errno = errno;
109 		sig_mutex_unlock(&tiptr->ti_lock);
110 		errno = sv_errno;
111 		return (-1);
112 	}
113 
114 	*flags = 0;
115 
116 	nbytes = _t_bytecount_upto_intmax(tiov, tiovcount);
117 	dataptr = NULL;
118 	if (nbytes != 0 && ((dataptr = malloc(nbytes)) == NULL)) {
119 		t_errno = TSYSERR;
120 		goto err_out;
121 	}
122 
123 	databuf.maxlen = nbytes;
124 	databuf.len = 0;
125 	databuf.buf = dataptr;
126 
127 	/*
128 	 * This is a call that may block indefinitely so we drop the
129 	 * lock and allow signals in MT case here and reacquire it.
130 	 * Error case should roll back state changes done above
131 	 * (happens to be no state change here)
132 	 */
133 	sig_mutex_unlock(&tiptr->ti_lock);
134 	if ((retval = getmsg(fd, &ctlbuf, &databuf, &flg)) < 0) {
135 		if (errno == EAGAIN)
136 			t_errno = TNODATA;
137 		else
138 			t_errno = TSYSERR;
139 		sv_errno = errno;
140 		sig_mutex_lock(&tiptr->ti_lock);
141 		errno = sv_errno;
142 		goto err_out;
143 	}
144 	sig_mutex_lock(&tiptr->ti_lock);
145 
146 	/*
147 	 * is there control piece with data?
148 	 */
149 	if (ctlbuf.len > 0) {
150 		if (ctlbuf.len < (int)sizeof (t_scalar_t)) {
151 			t_errno = TSYSERR;
152 			errno = EPROTO;
153 			goto err_out;
154 		}
155 
156 		/* LINTED pointer cast */
157 		pptr = (union T_primitives *)ctlbuf.buf;
158 
159 		switch (pptr->type) {
160 
161 		case T_UNITDATA_IND:
162 			if ((ctlbuf.len <
163 			    (int)sizeof (struct T_unitdata_ind)) ||
164 			    (pptr->unitdata_ind.OPT_length &&
165 			    (ctlbuf.len < (int)(pptr->unitdata_ind.OPT_length
166 			    + pptr->unitdata_ind.OPT_offset)))) {
167 				t_errno = TSYSERR;
168 				errno = EPROTO;
169 				goto err_out;
170 			}
171 
172 			if (unitdata->addr.maxlen > 0) {
173 				if (TLEN_GT_NLEN(pptr->unitdata_ind.SRC_length,
174 				    unitdata->addr.maxlen)) {
175 					t_errno = TBUFOVFLW;
176 					goto err_out;
177 				}
178 				(void) memcpy(unitdata->addr.buf,
179 				    ctlbuf.buf + pptr->unitdata_ind.SRC_offset,
180 				    (size_t)pptr->unitdata_ind.SRC_length);
181 				unitdata->addr.len =
182 				    pptr->unitdata_ind.SRC_length;
183 			}
184 			if (unitdata->opt.maxlen > 0) {
185 				if (TLEN_GT_NLEN(pptr->unitdata_ind.OPT_length,
186 				    unitdata->opt.maxlen)) {
187 					t_errno = TBUFOVFLW;
188 					goto err_out;
189 				}
190 				(void) memcpy(unitdata->opt.buf, ctlbuf.buf +
191 				    pptr->unitdata_ind.OPT_offset,
192 				    (size_t)pptr->unitdata_ind.OPT_length);
193 				unitdata->opt.len =
194 					pptr->unitdata_ind.OPT_length;
195 			}
196 			if (retval & MOREDATA)
197 				*flags |= T_MORE;
198 			/*
199 			 * No state changes happens on T_RCVUDATA
200 			 * event (NOOP). We do it only to log errors.
201 			 */
202 			_T_TX_NEXTSTATE(T_RCVUDATA, tiptr,
203 			    "t_rcvvudata: invalid state event T_RCVUDATA");
204 
205 			if (didalloc)
206 				free(ctlbuf.buf);
207 			else
208 				tiptr->ti_ctlbuf = ctlbuf.buf;
209 			_t_scatter(&databuf, tiov, tiovcount);
210 			if (dataptr != NULL)
211 				free(dataptr);
212 			sig_mutex_unlock(&tiptr->ti_lock);
213 			return (databuf.len);
214 
215 		case T_UDERROR_IND:
216 			if (_t_register_lookevent(tiptr, 0, 0, ctlbuf.buf,
217 				ctlbuf.len) < 0) {
218 				t_errno = TSYSERR;
219 				errno = ENOMEM;
220 				goto err_out;
221 			}
222 			t_errno = TLOOK;
223 			goto err_out;
224 
225 		default:
226 			break;
227 		}
228 
229 		t_errno = TSYSERR;
230 		errno = EPROTO;
231 		goto err_out;
232 
233 	} else {		/* else part of "if (ctlbuf.len > 0)" */
234 		unitdata->addr.len = 0;
235 		unitdata->opt.len = 0;
236 		/*
237 		 * only data in message no control piece
238 		 */
239 		if (retval & MOREDATA)
240 			*flags = T_MORE;
241 		/*
242 		 * No state transition occurs on
243 		 * event T_RCVUDATA. We do it only to
244 		 * log errors.
245 		 */
246 		_T_TX_NEXTSTATE(T_RCVUDATA, tiptr,
247 		    "t_rcvvudata: invalid state event T_RCVUDATA");
248 		if (didalloc)
249 			free(ctlbuf.buf);
250 		else
251 			tiptr->ti_ctlbuf = ctlbuf.buf;
252 		_t_scatter(&databuf, tiov, tiovcount);
253 		if (dataptr != NULL)
254 			free(dataptr);
255 		sig_mutex_unlock(&tiptr->ti_lock);
256 		return (databuf.len);
257 	}
258 	/* NOTREACHED */
259 err_out:
260 	sv_errno = errno;
261 	if (didalloc)
262 		free(ctlbuf.buf);
263 	else
264 		tiptr->ti_ctlbuf = ctlbuf.buf;
265 	if (dataptr != NULL)
266 		free(dataptr);
267 	sig_mutex_unlock(&tiptr->ti_lock);
268 	errno = sv_errno;
269 	return (-1);
270 }
271