xref: /illumos-gate/usr/src/uts/common/ktli/t_kconnect.c (revision 9b9d39d2a32ff806d2431dbcc50968ef1e6d46b2)
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 2009 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 /*
40  * Kernel TLI-like function to allow a trasnport endpoint to initiate a
41  * connection to another transport endpoint.  This function will wait for
42  * an ack and a T_CONN_CON before returning.
43  *
44  * Returns:
45  * 	0 on success, and if rcvcall is non-NULL it shall be
46  * 	filled with the connection confirm data.
47  * 	Otherwise a positive error code.
48  */
49 
50 #include <sys/param.h>
51 #include <sys/types.h>
52 #include <sys/user.h>
53 #include <sys/file.h>
54 #include <sys/vnode.h>
55 #include <sys/errno.h>
56 #include <sys/stream.h>
57 #include <sys/ioctl.h>
58 #include <sys/stropts.h>
59 #include <sys/tihdr.h>
60 #include <sys/timod.h>
61 #include <sys/tiuser.h>
62 #include <sys/t_kuser.h>
63 #include <sys/strsubr.h>
64 #include <sys/sysmacros.h>
65 #include <sys/strsun.h>
66 
67 
68 int
69 t_kconnect(TIUSER *tiptr, struct t_call *sndcall, struct t_call *rcvcall)
70 {
71 	int			len;
72 	int			msgsz;
73 	size_t			hdrsz;
74 	struct T_conn_req	*creq;
75 	union T_primitives	*pptr;
76 	mblk_t			*nbp;
77 	file_t			*fp;
78 	mblk_t			*bp;
79 	int			error;
80 	int			flag;
81 
82 	error = 0;
83 
84 	fp = tiptr->fp;
85 	msgsz = (int)TCONNREQSZ;
86 	/*
87 	 * Usually connect()s are performed with the credential of the caller;
88 	 * in this particular case we specifically use the credential of
89 	 * the opener as this call is typically done in the context of a user
90 	 * process but on behalf of the kernel, e.g., a client connection
91 	 * to a server which is later shared by different users.
92 	 * At open time, we make sure to set fp->f_cred to kcred if such is
93 	 * the case.
94 	 *
95 	 * Note: if the receiver uses SCM_UCRED/getpeerucred the pid will
96 	 * appear as -1.
97 	 */
98 	while (!(bp = allocb_cred(msgsz + sndcall->addr.len + sndcall->opt.len,
99 	    fp->f_cred, NOPID))) {
100 		if (strwaitbuf(msgsz + sndcall->addr.len + sndcall->opt.len,
101 		    BPRI_LO))
102 			return (ENOSR);
103 	}
104 
105 	/* LINTED pointer alignment */
106 	creq = (struct T_conn_req *)bp->b_wptr;
107 	creq->PRIM_type = T_CONN_REQ;
108 	creq->DEST_length = (t_scalar_t)sndcall->addr.len;
109 	creq->OPT_length = (t_scalar_t)sndcall->opt.len;
110 
111 	if (sndcall->addr.len) {
112 		bcopy(sndcall->addr.buf, (bp->b_wptr+msgsz), sndcall->addr.len);
113 		creq->DEST_offset = (t_scalar_t)msgsz;
114 		msgsz += sndcall->addr.len;
115 	} else
116 		creq->DEST_offset = (t_scalar_t)0;
117 
118 	if (sndcall->opt.len) {
119 		bcopy(sndcall->opt.buf, (bp->b_wptr+msgsz), sndcall->opt.len);
120 		creq->OPT_offset = (t_scalar_t)msgsz;
121 		msgsz += sndcall->opt.len;
122 	} else
123 		creq->OPT_offset = (t_scalar_t)0;
124 
125 	bp->b_datap->db_type = M_PROTO;
126 	bp->b_wptr += msgsz;
127 
128 	/*
129 	 * copy the users data, if any.
130 	 */
131 	if (sndcall->udata.len) {
132 		/*
133 		 * if CO then we would allocate a data block and
134 		 * put the users connect data into it.
135 		 */
136 		KTLILOG(1,
137 		    "Attempt to send connectionless data on T_CONN_REQ\n", 0);
138 		freemsg(bp);
139 		return (EPROTO);
140 	}
141 
142 	flag = fp->f_flag;
143 
144 	/*
145 	 * send it
146 	 */
147 	if ((error = tli_send(tiptr, bp, flag)) != 0)
148 		return (error);
149 
150 	/*
151 	 * wait for acknowledgment
152 	 */
153 	if ((error = get_ok_ack(tiptr, T_CONN_REQ, flag)) != 0)
154 		return (error);
155 
156 	bp = NULL;
157 	/*
158 	 * wait for CONfirm
159 	 */
160 	if ((error = tli_recv(tiptr, &bp, flag)) != 0)
161 		return (error);
162 
163 	if (bp->b_datap->db_type != M_PROTO) {
164 		freemsg(bp);
165 		return (EPROTO);
166 	}
167 
168 	/* LINTED pointer alignment */
169 	pptr = (union T_primitives *)bp->b_rptr;
170 	switch (pptr->type) {
171 	case T_CONN_CON:
172 		hdrsz = MBLKL(bp);
173 
174 		/*
175 		 * check everything for consistency
176 		 */
177 		if (hdrsz < TCONNCONSZ ||
178 		    hdrsz < (pptr->conn_con.OPT_length +
179 		    pptr->conn_con.OPT_offset) ||
180 		    hdrsz < (pptr->conn_con.RES_length +
181 		    pptr->conn_con.RES_offset)) {
182 			error = EPROTO;
183 			freemsg(bp);
184 			break;
185 		}
186 
187 		if (rcvcall != NULL) {
188 			/*
189 			 * okay, so now we copy them
190 			 */
191 			len = MIN(pptr->conn_con.RES_length,
192 			    rcvcall->addr.maxlen);
193 			bcopy(bp->b_rptr + pptr->conn_con.RES_offset,
194 			    rcvcall->addr.buf, len);
195 			rcvcall->addr.len = len;
196 
197 			len = MIN(pptr->conn_con.OPT_length,
198 			    rcvcall->opt.maxlen);
199 			bcopy(bp->b_rptr + pptr->conn_con.OPT_offset,
200 			    rcvcall->opt.buf, len);
201 			rcvcall->opt.len = len;
202 
203 			if (bp->b_cont) {
204 				nbp = bp;
205 				bp = bp->b_cont;
206 				msgsz = (int)MBLKL(bp);
207 				len = MIN(msgsz, rcvcall->udata.maxlen);
208 				bcopy(bp->b_rptr, rcvcall->udata.buf, len);
209 				rcvcall->udata.len = len;
210 				freemsg(nbp);
211 			}
212 		} else {
213 			freemsg(bp);
214 		}
215 		break;
216 
217 	case T_DISCON_IND:
218 		/*
219 		 * TCP puts the errno here, i.e.
220 		 * ETIMEDOUT, ECONNREFUSED
221 		 */
222 		error = pptr->discon_ind.DISCON_reason;
223 		freemsg(bp);
224 		break;
225 
226 	default:
227 		error = EPROTO;
228 		freemsg(bp);
229 		break;
230 	}
231 	return (error);
232 }
233