xref: /illumos-gate/usr/src/uts/common/ktli/t_krcvudat.c (revision 09b0d01c5bc323b8ee7043100e09aded27cc12ab)
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 2014 Gary Mills
23  * Copyright 2008 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 /*
41  * Kernel TLI-like function to read a datagram off of a
42  * transport endpoints stream head.
43  *
44  * Returns:
45  * 	0	On success or positive error code.
46  * 		On sucess, type is set to:
47  * 	T_DATA		If normal data has been received
48  * 	T_UDERR		If an error indication has been received,
49  * 			in which case uderr contains the unitdata
50  * 			error number.
51  */
52 
53 #include <sys/param.h>
54 #include <sys/types.h>
55 #include <sys/user.h>
56 #include <sys/file.h>
57 #include <sys/errno.h>
58 #include <sys/stream.h>
59 #include <sys/strsubr.h>
60 #include <sys/vnode.h>
61 #include <sys/ioctl.h>
62 #include <sys/stropts.h>
63 #include <sys/tihdr.h>
64 #include <sys/timod.h>
65 #include <sys/tiuser.h>
66 #include <sys/t_kuser.h>
67 #include <sys/sysmacros.h>
68 #include <sys/strsun.h>
69 
70 
71 int
t_krcvudata(TIUSER * tiptr,struct t_kunitdata * unitdata,int * type,int * uderr)72 t_krcvudata(TIUSER *tiptr, struct t_kunitdata *unitdata, int *type, int *uderr)
73 {
74 	int			len;
75 	size_t			hdrsz;
76 	union T_primitives	*pptr;
77 	struct file		*fp;
78 	mblk_t			*bp;
79 	mblk_t			*nbp;
80 	mblk_t			*mp;
81 	mblk_t			*tmp;
82 	int			error;
83 	int			flag;
84 
85 	fp = tiptr->fp;
86 
87 	if (type == NULL || uderr == NULL)
88 		return (EINVAL);
89 
90 	error = 0;
91 	unitdata->udata.buf = NULL;
92 
93 	if (unitdata->udata.udata_mp) {
94 		KTLILOG(2, "t_krcvudata: freeing existing message block\n", 0);
95 		freemsg(unitdata->udata.udata_mp);
96 		unitdata->udata.udata_mp = NULL;
97 	}
98 
99 	/*
100 	 * XXX	Grabbing a mutex to do an atomic operation seems pointless
101 	 */
102 	mutex_enter(&fp->f_tlock);
103 	flag = fp->f_flag;
104 	mutex_exit(&fp->f_tlock);
105 
106 	if ((error = tli_recv(tiptr, &bp, flag)) != 0)
107 		return (error);
108 
109 	/*
110 	 * Got something
111 	 */
112 	switch (bp->b_datap->db_type) {
113 	case M_PROTO:
114 		/* LINTED pointer alignment */
115 		pptr = (union T_primitives *)bp->b_rptr;
116 		switch (pptr->type) {
117 		case T_UNITDATA_IND:
118 			KTLILOG(2, "t_krcvudata: Got T_UNITDATA_IND\n", 0);
119 			hdrsz = MBLKL(bp);
120 
121 			/*
122 			 * check everything for consistency
123 			 */
124 			if (hdrsz < TUNITDATAINDSZ ||
125 			    hdrsz < (pptr->unitdata_ind.OPT_length +
126 			    pptr->unitdata_ind.OPT_offset) ||
127 			    hdrsz < (pptr->unitdata_ind.SRC_length +
128 			    pptr->unitdata_ind.SRC_offset)) {
129 				error = EPROTO;
130 				freemsg(bp);
131 				break;
132 			}
133 
134 			/*
135 			 * okay, so now we copy them
136 			 */
137 			len = MIN(pptr->unitdata_ind.SRC_length,
138 			    unitdata->addr.maxlen);
139 			bcopy(bp->b_rptr + pptr->unitdata_ind.SRC_offset,
140 			    unitdata->addr.buf, len);
141 			unitdata->addr.len = len;
142 
143 			len = MIN(pptr->unitdata_ind.OPT_length,
144 			    unitdata->opt.maxlen);
145 			bcopy(bp->b_rptr + pptr->unitdata_ind.OPT_offset,
146 			    unitdata->opt.buf, len);
147 			unitdata->opt.len = len;
148 
149 			bp->b_rptr += hdrsz;
150 
151 			/*
152 			 * we assume that the client knows how to deal
153 			 * with a set of linked mblks, so all we do is
154 			 * make a pass and remove any that are zero
155 			 * length.
156 			 */
157 			nbp = NULL;
158 			mp = bp;
159 			while (mp) {
160 				if (bp->b_wptr == bp->b_rptr) {
161 					KTLILOG(2,
162 					    "t_krcvudata: zero length block\n",
163 					    0);
164 					tmp = mp->b_cont;
165 					if (nbp)
166 						nbp->b_cont = tmp;
167 					else
168 						bp = tmp;
169 
170 					freeb(mp);
171 					mp = tmp;
172 				} else {
173 					nbp = mp;
174 					mp = mp->b_cont;
175 				}
176 			}
177 #ifdef KTLIDEBUG
178 {
179 	mblk_t *tp;
180 
181 	tp = bp;
182 	while (tp) {
183 		struct datab *dbp = tp->b_datap;
184 		frtn_t *frp = dbp->db_frtnp;
185 
186 		KTLILOG(2, "t_krcvudata: bp %x, ", tp);
187 		KTLILOG(2, "db_size %x, ", dbp->db_lim - dbp->db_base);
188 		KTLILOG(2, "db_ref %x", dbp->db_ref);
189 
190 		if (frp != NULL)
191 			KTLILOG(2, ", func: %x", frp->free_func);
192 			KTLILOG(2, ", arg %x\n", frp->free_arg);
193 		} else
194 			KTLILOG(2, "\n", 0);
195 		tp = tp->b_cont;
196 	}
197 }
198 #endif /* KTLIDEBUG */
199 			/*
200 			 * now just point the users mblk
201 			 * pointer to what we received.
202 			 */
203 			if (bp == NULL) {
204 				KTLILOG(2, "t_krcvudata: No data\n", 0);
205 				error = EPROTO;
206 				break;
207 			}
208 			if (bp->b_wptr != bp->b_rptr) {
209 			    if (!IS_P2ALIGNED(bp->b_rptr, sizeof (uint32_t)))
210 					if (!pullupmsg(bp, MBLKL(bp))) {
211 						KTLILOG(1,
212 					"t_krcvudata:  pullupmsg failed\n", 0);
213 						error = EIO;
214 						freemsg(bp);
215 						break;
216 					}
217 				unitdata->udata.buf = (char *)bp->b_rptr;
218 				unitdata->udata.len = (uint_t)MBLKL(bp);
219 
220 				KTLILOG(2, "t_krcvudata: got %d bytes\n",
221 				    unitdata->udata.len);
222 				unitdata->udata.udata_mp = bp;
223 			} else {
224 				KTLILOG(2,
225 				    "t_krcvudata: 0 length data message\n", 0);
226 				freemsg(bp);
227 				unitdata->udata.len = 0;
228 			}
229 			*type = T_DATA;
230 			break;
231 
232 		case T_UDERROR_IND:
233 			KTLILOG(2, "t_krcvudata: Got T_UDERROR_IND\n", 0);
234 			hdrsz = MBLKL(bp);
235 
236 			/*
237 			 * check everything for consistency
238 			 */
239 			if (hdrsz < TUDERRORINDSZ ||
240 			    hdrsz < (pptr->uderror_ind.OPT_length +
241 			    pptr->uderror_ind.OPT_offset) ||
242 			    hdrsz < (pptr->uderror_ind.DEST_length +
243 			    pptr->uderror_ind.DEST_offset)) {
244 				error = EPROTO;
245 				freemsg(bp);
246 				break;
247 			}
248 
249 			if (pptr->uderror_ind.DEST_length >
250 			    (int)unitdata->addr.maxlen ||
251 			    pptr->uderror_ind.OPT_length >
252 			    (int)unitdata->opt.maxlen) {
253 				error = EMSGSIZE;
254 				freemsg(bp);
255 				break;
256 			}
257 
258 			/*
259 			 * okay, so now we copy them
260 			 */
261 			bcopy(bp->b_rptr + pptr->uderror_ind.DEST_offset,
262 			    unitdata->addr.buf,
263 			    (size_t)pptr->uderror_ind.DEST_length);
264 			unitdata->addr.len = pptr->uderror_ind.DEST_length;
265 
266 			bcopy(bp->b_rptr + pptr->uderror_ind.OPT_offset,
267 			    unitdata->opt.buf,
268 			    (size_t)pptr->uderror_ind.OPT_length);
269 			unitdata->opt.len = pptr->uderror_ind.OPT_length;
270 
271 			*uderr = pptr->uderror_ind.ERROR_type;
272 
273 			unitdata->udata.buf = NULL;
274 			unitdata->udata.udata_mp = NULL;
275 			unitdata->udata.len = 0;
276 
277 			freemsg(bp);
278 
279 			*type = T_UDERR;
280 			break;
281 
282 		default:
283 			KTLILOG(1,
284 			    "t_krcvudata: Unknown transport primitive %d\n",
285 			    pptr->type);
286 			error = EPROTO;
287 			freemsg(bp);
288 			break;
289 		}
290 		break;
291 
292 	case M_FLUSH:
293 		KTLILOG(1, "t_krcvudata: tli_recv returned M_FLUSH\n", 0);
294 		freemsg(bp);
295 		error = EBADMSG;
296 		break;
297 
298 	default:
299 		KTLILOG(1, "t_krcvudata: unknown message type %x\n",
300 		    bp->b_datap->db_type);
301 		freemsg(bp);
302 		error = EBADMSG;
303 		break;
304 	}
305 
306 	return (error);
307 }
308