xref: /illumos-gate/usr/src/uts/common/ktli/t_krcvudat.c (revision 581cede61ac9c14d8d4ea452562a567189eead78)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
27 /*	  All Rights Reserved  	*/
28 
29 /*
30  * University Copyright- Copyright (c) 1982, 1986, 1988
31  * The Regents of the University of California
32  * All Rights Reserved
33  *
34  * University Acknowledgment- Portions of this document are derived from
35  * software developed by the University of California, Berkeley, and its
36  * contributors.
37  */
38 
39 #pragma ident	"%Z%%M%	%I%	%E% SMI"
40 
41 /*
42  * Kernel TLI-like function to read a datagram off of a
43  * transport endpoints stream head.
44  *
45  * Returns:
46  * 	0	On success or positive error code.
47  * 		On sucess, type is set to:
48  * 	T_DATA		If normal data has been received
49  * 	T_UDERR		If an error indication has been received,
50  * 			in which case uderr contains the unitdata
51  * 			error number.
52  * 	T_ERROR
53  */
54 
55 #include <sys/param.h>
56 #include <sys/types.h>
57 #include <sys/user.h>
58 #include <sys/file.h>
59 #include <sys/errno.h>
60 #include <sys/stream.h>
61 #include <sys/strsubr.h>
62 #include <sys/vnode.h>
63 #include <sys/ioctl.h>
64 #include <sys/stropts.h>
65 #include <sys/tihdr.h>
66 #include <sys/timod.h>
67 #include <sys/tiuser.h>
68 #include <sys/t_kuser.h>
69 #include <sys/sysmacros.h>
70 #include <sys/strsun.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 = MBLKL(bp);
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, MBLKL(bp))) {
213 						KTLILOG(1,
214 					"t_krcvudata:  pullupmsg failed\n", 0);
215 						error = EIO;
216 						freemsg(bp);
217 						break;
218 					}
219 				unitdata->udata.buf = (char *)bp->b_rptr;
220 				unitdata->udata.len = (uint_t)MBLKL(bp);
221 
222 				KTLILOG(2, "t_krcvudata: got %d bytes\n",
223 				    unitdata->udata.len);
224 				unitdata->udata.udata_mp = bp;
225 			} else {
226 				KTLILOG(2,
227 				    "t_krcvudata: 0 length data message\n", 0);
228 				freemsg(bp);
229 				unitdata->udata.len = 0;
230 			}
231 			*type = T_DATA;
232 			break;
233 
234 		case T_UDERROR_IND:
235 			KTLILOG(2, "t_krcvudata: Got T_UDERROR_IND\n", 0);
236 			hdrsz = MBLKL(bp);
237 
238 			/*
239 			 * check everything for consistency
240 			 */
241 			if (hdrsz < TUDERRORINDSZ ||
242 			    hdrsz < (pptr->uderror_ind.OPT_length +
243 			    pptr->uderror_ind.OPT_offset) ||
244 			    hdrsz < (pptr->uderror_ind.DEST_length +
245 			    pptr->uderror_ind.DEST_offset)) {
246 				error = EPROTO;
247 				freemsg(bp);
248 				break;
249 			}
250 
251 			if (pptr->uderror_ind.DEST_length >
252 			    (int)unitdata->addr.maxlen ||
253 			    pptr->uderror_ind.OPT_length >
254 			    (int)unitdata->opt.maxlen) {
255 				error = EMSGSIZE;
256 				freemsg(bp);
257 				break;
258 			}
259 
260 			/*
261 			 * okay, so now we copy them
262 			 */
263 			bcopy(bp->b_rptr + pptr->uderror_ind.DEST_offset,
264 			    unitdata->addr.buf,
265 			    (size_t)pptr->uderror_ind.DEST_length);
266 			unitdata->addr.len = pptr->uderror_ind.DEST_length;
267 
268 			bcopy(bp->b_rptr + pptr->uderror_ind.OPT_offset,
269 			    unitdata->opt.buf,
270 			    (size_t)pptr->uderror_ind.OPT_length);
271 			unitdata->opt.len = pptr->uderror_ind.OPT_length;
272 
273 			*uderr = pptr->uderror_ind.ERROR_type;
274 
275 			unitdata->udata.buf = NULL;
276 			unitdata->udata.udata_mp = NULL;
277 			unitdata->udata.len = 0;
278 
279 			freemsg(bp);
280 
281 			*type = T_UDERR;
282 			break;
283 
284 		default:
285 			KTLILOG(1,
286 			    "t_krcvudata: Unknown transport primitive %d\n",
287 			    pptr->type);
288 			error = EPROTO;
289 			freemsg(bp);
290 			break;
291 		}
292 		break;
293 
294 	case M_FLUSH:
295 		KTLILOG(1, "t_krcvudata: tli_recv returned M_FLUSH\n", 0);
296 		freemsg(bp);
297 		*type = T_ERROR;
298 		break;
299 
300 	default:
301 		KTLILOG(1, "t_krcvudata: unknown message type %x\n",
302 		    bp->b_datap->db_type);
303 		freemsg(bp);
304 		*type = T_ERROR;
305 		break;
306 	}
307 
308 	return (error);
309 }
310