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 2001 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 /*
43  * Kernel TLI-like function to read a datagram off of a
44  * transport endpoints stream head.
45  *
46  * Returns:
47  * 	0	On success or positive error code.
48  * 		On sucess, type is set to:
49  * 	T_DATA		If normal data has been received
50  * 	T_UDERR		If an error indication has been received,
51  * 			in which case uderr contains the unitdata
52  * 			error number.
53  * 	T_ERROR
54  */
55 
56 #include <sys/param.h>
57 #include <sys/types.h>
58 #include <sys/user.h>
59 #include <sys/file.h>
60 #include <sys/errno.h>
61 #include <sys/stream.h>
62 #include <sys/strsubr.h>
63 #include <sys/vnode.h>
64 #include <sys/ioctl.h>
65 #include <sys/stropts.h>
66 #include <sys/tihdr.h>
67 #include <sys/timod.h>
68 #include <sys/tiuser.h>
69 #include <sys/t_kuser.h>
70 #include <sys/sysmacros.h>
71 
72 
73 int
74 t_krcvudata(TIUSER *tiptr, struct t_kunitdata *unitdata, int *type, int *uderr)
75 {
76 	int			len;
77 	size_t			hdrsz;
78 	union T_primitives	*pptr;
79 	struct file		*fp;
80 	mblk_t			*bp;
81 	mblk_t			*nbp;
82 	mblk_t			*mp;
83 	mblk_t			*tmp;
84 	int			error;
85 	int			flag;
86 
87 	fp = tiptr->fp;
88 
89 	if (type == NULL || uderr == NULL)
90 		return (EINVAL);
91 
92 	error = 0;
93 	unitdata->udata.buf = NULL;
94 
95 	if (unitdata->udata.udata_mp) {
96 		KTLILOG(2, "t_krcvudata: freeing existing message block\n", 0);
97 		freemsg(unitdata->udata.udata_mp);
98 		unitdata->udata.udata_mp = NULL;
99 	}
100 
101 	/*
102 	 * XXX	Grabbing a mutex to do an atomic operation seems pointless
103 	 */
104 	mutex_enter(&fp->f_tlock);
105 	flag = fp->f_flag;
106 	mutex_exit(&fp->f_tlock);
107 
108 	if ((error = tli_recv(tiptr, &bp, flag)) != 0)
109 		return (error);
110 
111 	/*
112 	 * Got something
113 	 */
114 	switch (bp->b_datap->db_type) {
115 	case M_PROTO:
116 		/* LINTED pointer alignment */
117 		pptr = (union T_primitives *)bp->b_rptr;
118 		switch (pptr->type) {
119 		case T_UNITDATA_IND:
120 			KTLILOG(2, "t_krcvudata: Got T_UNITDATA_IND\n", 0);
121 			hdrsz = bp->b_wptr - bp->b_rptr;
122 
123 			/*
124 			 * check everything for consistency
125 			 */
126 			if (hdrsz < TUNITDATAINDSZ ||
127 			    hdrsz < (pptr->unitdata_ind.OPT_length +
128 			    pptr->unitdata_ind.OPT_offset) ||
129 			    hdrsz < (pptr->unitdata_ind.SRC_length +
130 			    pptr->unitdata_ind.SRC_offset)) {
131 				error = EPROTO;
132 				freemsg(bp);
133 				break;
134 			}
135 
136 			/*
137 			 * okay, so now we copy them
138 			 */
139 			len = MIN(pptr->unitdata_ind.SRC_length,
140 			    unitdata->addr.maxlen);
141 			bcopy(bp->b_rptr + pptr->unitdata_ind.SRC_offset,
142 			    unitdata->addr.buf, len);
143 			unitdata->addr.len = len;
144 
145 			len = MIN(pptr->unitdata_ind.OPT_length,
146 			    unitdata->opt.maxlen);
147 			bcopy(bp->b_rptr + pptr->unitdata_ind.OPT_offset,
148 			    unitdata->opt.buf, len);
149 			unitdata->opt.len = len;
150 
151 			bp->b_rptr += hdrsz;
152 
153 			/*
154 			 * we assume that the client knows how to deal
155 			 * with a set of linked mblks, so all we do is
156 			 * make a pass and remove any that are zero
157 			 * length.
158 			 */
159 			nbp = NULL;
160 			mp = bp;
161 			while (mp) {
162 				if (!(bp->b_wptr-bp->b_rptr)) {
163 					KTLILOG(2,
164 					    "t_krcvudata: zero length block\n",
165 					    0);
166 					tmp = mp->b_cont;
167 					if (nbp)
168 						nbp->b_cont = tmp;
169 					else
170 						bp = tmp;
171 
172 					freeb(mp);
173 					mp = tmp;
174 				} else {
175 					nbp = mp;
176 					mp = mp->b_cont;
177 				}
178 			}
179 #ifdef KTLIDEBUG
180 {
181 	mblk_t *tp;
182 
183 	tp = bp;
184 	while (tp) {
185 		struct datab *dbp = tp->b_datap;
186 		frtn_t *frp = dbp->db_frtnp;
187 
188 		KTLILOG(2, "t_krcvudata: bp %x, ", tp);
189 		KTLILOG(2, "db_size %x, ", dbp->db_lim - dbp->db_base);
190 		KTLILOG(2, "db_ref %x", dbp->db_ref);
191 
192 		if (frp != NULL)
193 			KTLILOG(2, ", func: %x", frp->free_func);
194 			KTLILOG(2, ", arg %x\n", frp->free_arg);
195 		} else
196 			KTLILOG(2, "\n", 0);
197 		tp = tp->b_cont;
198 	}
199 }
200 #endif /* KTLIDEBUG */
201 			/*
202 			 * now just point the users mblk
203 			 * pointer to what we received.
204 			 */
205 			if (bp == NULL) {
206 				KTLILOG(2, "t_krcvudata: No data\n", 0);
207 				error = EPROTO;
208 				break;
209 			}
210 			if (bp->b_wptr != bp->b_rptr) {
211 			    if (!IS_P2ALIGNED(bp->b_rptr, sizeof (uint32_t)))
212 					if (!pullupmsg(bp,
213 					    bp->b_wptr - bp->b_rptr)) {
214 						KTLILOG(1,
215 					"t_krcvudata:  pullupmsg failed\n", 0);
216 						error = EIO;
217 						freemsg(bp);
218 						break;
219 					}
220 				unitdata->udata.buf = (char *)bp->b_rptr;
221 				unitdata->udata.len = (uint)(bp->b_wptr -
222 				    bp->b_rptr);
223 
224 				KTLILOG(2, "t_krcvudata: got %d bytes\n",
225 				    unitdata->udata.len);
226 				unitdata->udata.udata_mp = bp;
227 			} else {
228 				KTLILOG(2,
229 				    "t_krcvudata: 0 length data message\n", 0);
230 				freemsg(bp);
231 				unitdata->udata.len = 0;
232 			}
233 			*type = T_DATA;
234 			break;
235 
236 		case T_UDERROR_IND:
237 			KTLILOG(2, "t_krcvudata: Got T_UDERROR_IND\n", 0);
238 			hdrsz = bp->b_wptr - bp->b_rptr;
239 
240 			/*
241 			 * check everything for consistency
242 			 */
243 			if (hdrsz < TUDERRORINDSZ ||
244 			    hdrsz < (pptr->uderror_ind.OPT_length +
245 			    pptr->uderror_ind.OPT_offset) ||
246 			    hdrsz < (pptr->uderror_ind.DEST_length +
247 			    pptr->uderror_ind.DEST_offset)) {
248 				error = EPROTO;
249 				freemsg(bp);
250 				break;
251 			}
252 
253 			if (pptr->uderror_ind.DEST_length >
254 			    (int)unitdata->addr.maxlen ||
255 			    pptr->uderror_ind.OPT_length >
256 			    (int)unitdata->opt.maxlen) {
257 				error = EMSGSIZE;
258 				freemsg(bp);
259 				break;
260 			}
261 
262 			/*
263 			 * okay, so now we copy them
264 			 */
265 			bcopy(bp->b_rptr + pptr->uderror_ind.DEST_offset,
266 			    unitdata->addr.buf,
267 			    (size_t)pptr->uderror_ind.DEST_length);
268 			unitdata->addr.len = pptr->uderror_ind.DEST_length;
269 
270 			bcopy(bp->b_rptr + pptr->uderror_ind.OPT_offset,
271 			    unitdata->opt.buf,
272 			    (size_t)pptr->uderror_ind.OPT_length);
273 			unitdata->opt.len = pptr->uderror_ind.OPT_length;
274 
275 			*uderr = pptr->uderror_ind.ERROR_type;
276 
277 			unitdata->udata.buf = NULL;
278 			unitdata->udata.udata_mp = NULL;
279 			unitdata->udata.len = 0;
280 
281 			freemsg(bp);
282 
283 			*type = T_UDERR;
284 			break;
285 
286 		default:
287 			KTLILOG(1,
288 			    "t_krcvudata: Unknown transport primitive %d\n",
289 			    pptr->type);
290 			error = EPROTO;
291 			freemsg(bp);
292 			break;
293 		}
294 		break;
295 
296 	case M_FLUSH:
297 		KTLILOG(1, "t_krcvudata: tli_recv returned M_FLUSH\n", 0);
298 		freemsg(bp);
299 		*type = T_ERROR;
300 		break;
301 
302 	default:
303 		KTLILOG(1, "t_krcvudata: unknown message type %x\n",
304 		    bp->b_datap->db_type);
305 		freemsg(bp);
306 		*type = T_ERROR;
307 		break;
308 	}
309 
310 	return (error);
311 }
312