xref: /illumos-gate/usr/src/lib/libnsl/nsl/t_optmgmt.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
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 (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
24 /*	  All Rights Reserved  	*/
25 
26 /*
27  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #include "mt.h"
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include <errno.h>
36 #include <sys/stream.h>
37 #define	_SUN_TPI_VERSION 2
38 #include <sys/tihdr.h>
39 #include <sys/timod.h>
40 #include <xti.h>
41 #include <signal.h>
42 #include <syslog.h>
43 #include <stropts.h>
44 #include "tx.h"
45 
46 /*
47  * The following is based on XTI standard.
48  */
49 #define	ALIGN_XTI_opthdr_size	(sizeof (t_uscalar_t))
50 
51 #define	ROUNDUP_XTI_opthdr(p)	(((p) +\
52 		(ALIGN_XTI_opthdr_size-1)) & ~(ALIGN_XTI_opthdr_size-1))
53 #define	ISALIGNED_XTI_opthdr(p)	\
54 	(((ulong_t)(p) & (ALIGN_XTI_opthdr_size - 1)) == 0)
55 
56 int
57 _tx_optmgmt(
58 	int fd,
59 	const struct t_optmgmt *req,
60 	struct t_optmgmt *ret,
61 	int api_semantics
62 )
63 {
64 	int size, sv_errno;
65 	struct strbuf ctlbuf;
66 	struct T_optmgmt_req *optreq;
67 	struct T_optmgmt_ack *optack;
68 	struct _ti_user *tiptr;
69 	sigset_t mask;
70 	int didalloc, retlen;
71 	struct t_opthdr *opt, *next_opt;
72 	struct t_opthdr *opt_start, *opt_end;
73 	t_uscalar_t first_opt_level;
74 	t_scalar_t optlen;
75 
76 	if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL)
77 		return (-1);
78 
79 	/*
80 	 * We block all signals during the TI_OPTMGMT operation
81 	 * as option change being done could potentially be a
82 	 * non-idempotent operation.
83 	 * Note that sig_mutex_lock() only defers signals, it does not
84 	 * block them, so interruptible syscalls could still get EINTR.
85 	 */
86 	(void) thr_sigsetmask(SIG_SETMASK, &fillset, &mask);
87 	sig_mutex_lock(&tiptr->ti_lock);
88 
89 	/*
90 	 * Acquire buf for use in sending/receiving of the message.
91 	 * Note: assumes (correctly) that ti_ctlsize is large enough
92 	 * to hold sizeof (struct T_bind_req)
93 	 */
94 	if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) {
95 		sv_errno = errno;
96 		sig_mutex_unlock(&tiptr->ti_lock);
97 		(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
98 		errno = sv_errno;
99 		return (-1);
100 	}
101 
102 	/*
103 	 * effective option length in local variable "optlen"
104 	 * Note: can change for XTI for T_ALLOPT. XTI spec states
105 	 * that options after the T_ALLOPT option are to be ignored
106 	 * therefore we trncate the option buffer there and modify
107 	 * the effective length accordingly later.
108 	 */
109 	optlen = req->opt.len;
110 
111 	if (_T_IS_XTI(api_semantics) && (optlen > 0)) {
112 		/*
113 		 * Verify integrity of option buffer according to
114 		 * XTI t_optmgmt() semantics.
115 		 */
116 
117 		if (req->opt.buf == NULL ||
118 		    optlen < (t_scalar_t)sizeof (struct t_opthdr)) {
119 			/* option buffer should atleast have an t_opthdr */
120 			t_errno = TBADOPT;
121 			goto err_out;
122 		}
123 
124 		/* LINTED pointer cast */
125 		opt_start = (struct t_opthdr *)req->opt.buf;
126 
127 		/*
128 		 * XXX We interpret that an option has to start on an
129 		 * aligned buffer boundary. This is not very explcit in
130 		 * XTI spec in text but the picture in Section 6.2 shows
131 		 * "opt.buf" at start of buffer and in combination with
132 		 * text can be construed to be restricting it to start
133 		 * on an aligned boundary. [Whether similar restriction
134 		 * applies to output buffer "ret->opt.buf" is an "interesting
135 		 * question" but we ignore it for now as that is the problem
136 		 * for the application not our implementation which will
137 		 * does not enforce any alignment requirement.]
138 		 *
139 		 * If start of buffer is not aligned, we signal an error.
140 		 */
141 		if (!(ISALIGNED_XTI_opthdr(opt_start))) {
142 			t_errno = TBADOPT;
143 			goto err_out;
144 		}
145 
146 		/* LINTED pointer cast */
147 		opt_end = (struct t_opthdr *)((char *)opt_start +
148 						optlen);
149 
150 		/*
151 		 * Make sure we have enough in the message to dereference
152 		 * the option header.
153 		 */
154 		if ((uchar_t *)opt_start + sizeof (struct t_opthdr)
155 		    > (uchar_t *)opt_end) {
156 			t_errno = TBADOPT;
157 			goto err_out;
158 		}
159 		/*
160 		 * If there are multiple options, they all have to be
161 		 * the same level (so says XTI semantics).
162 		 */
163 		first_opt_level = opt_start->level;
164 
165 		for (opt = opt_start; opt < opt_end; opt = next_opt) {
166 			/*
167 			 * Make sure we have enough in the message to
168 			 * dereference the option header.
169 			 */
170 			if ((uchar_t *)opt_start + sizeof (struct t_opthdr)
171 			    > (uchar_t *)opt_end) {
172 				t_errno = TBADOPT;
173 				goto err_out;
174 			}
175 			/*
176 			 * We now compute pointer to next option in buffer
177 			 * 'next_opt' the next_opt computation above below
178 			 * 'opt->len' initialized by application which cannot
179 			 * be trusted. The usual value too large will be
180 			 * captured by the loop termination condition above.
181 			 * We check for the following which it will miss.
182 			 *	(1)pointer space wraparound arithmetic overflow
183 			 *	(2)last option in buffer with 'opt->len' being
184 			 *	  too large
185 			 *	(only reason 'next_opt' should equal or exceed
186 			 *	'opt_end' for last option is roundup unless
187 			 *	length is too-large/invalid)
188 			 *	(3) we also enforce the XTI restriction that
189 			 *	   all options in the buffer have to be the
190 			 *	   same level.
191 			 */
192 			/* LINTED pointer cast */
193 			next_opt = (struct t_opthdr *)((uchar_t *)opt +
194 			    ROUNDUP_XTI_opthdr(opt->len));
195 
196 			if ((uchar_t *)next_opt < (uchar_t *)opt || /* (1) */
197 			    ((next_opt >= opt_end) &&
198 				(((uchar_t *)next_opt - (uchar_t *)opt_end) >=
199 				    ALIGN_XTI_opthdr_size)) || /* (2) */
200 			    (opt->level != first_opt_level)) { /* (3) */
201 				t_errno = TBADOPT;
202 				goto err_out;
203 			}
204 
205 			/*
206 			 * XTI semantics: options in the buffer after
207 			 * the T_ALLOPT option can be ignored
208 			 */
209 			if (opt->name == T_ALLOPT) {
210 				if (next_opt < opt_end) {
211 					/*
212 					 * there are options following, ignore
213 					 * them and truncate input
214 					 */
215 					optlen = (t_scalar_t)((uchar_t *)
216 					    next_opt - (uchar_t *)opt_start);
217 					opt_end = next_opt;
218 				}
219 			}
220 		}
221 	}
222 
223 	/* LINTED pointer cast */
224 	optreq = (struct T_optmgmt_req *)ctlbuf.buf;
225 	if (_T_IS_XTI(api_semantics))
226 		optreq->PRIM_type = T_OPTMGMT_REQ;
227 	else
228 		optreq->PRIM_type = T_SVR4_OPTMGMT_REQ;
229 
230 	optreq->OPT_length = optlen;
231 	optreq->OPT_offset = 0;
232 	optreq->MGMT_flags = req->flags;
233 	size = (int)sizeof (struct T_optmgmt_req);
234 
235 	if (optlen) {
236 		if (_t_aligned_copy(&ctlbuf, optlen, size,
237 		    req->opt.buf, &optreq->OPT_offset) < 0) {
238 			/*
239 			 * Aligned copy will overflow buffer allocated
240 			 * based on maximum transport option size information
241 			 */
242 			t_errno = TBADOPT;
243 			goto err_out;
244 		}
245 		size = optreq->OPT_offset + optreq->OPT_length;
246 	}
247 
248 	if (_t_do_ioctl(fd, ctlbuf.buf, size, TI_OPTMGMT, &retlen) < 0)
249 		goto err_out;
250 
251 	if (retlen < (int)sizeof (struct T_optmgmt_ack)) {
252 		t_errno = TSYSERR;
253 		errno = EIO;
254 		goto err_out;
255 	}
256 
257 	/* LINTED pointer cast */
258 	optack = (struct T_optmgmt_ack *)ctlbuf.buf;
259 
260 	if (_T_IS_TLI(api_semantics) || ret->opt.maxlen > 0) {
261 		if (TLEN_GT_NLEN(optack->OPT_length, ret->opt.maxlen)) {
262 			t_errno = TBUFOVFLW;
263 			goto err_out;
264 		}
265 		(void) memcpy(ret->opt.buf,
266 		    (char *)(ctlbuf.buf + optack->OPT_offset),
267 		    (unsigned int) optack->OPT_length);
268 		ret->opt.len = optack->OPT_length;
269 	}
270 
271 	/*
272 	 * Note: TPI is not clear about what really is carries in the
273 	 * T_OPTMGMT_ACK MGMT_flags fields. For T_OPTMGMT_ACK in response
274 	 * to T_SVR4_OPTMGMT_REQ, the Internet protocols in Solaris 2.X return
275 	 * the result code only (T_SUCCESS). For T_OPTMGMT_ACK in response
276 	 * to T_OPTMGMT_REQ, currently "worst status" code required for
277 	 * XTI is carried from the set of options OR'd with request flag.
278 	 * (This can change in future and "worst status" computation done
279 	 * with a scan in this routine.
280 	 *
281 	 * Note: Even for T_OPTMGMT_ACK is response to T_SVR4_OPTMGMT_REQ,
282 	 * removing request flag should be OK though it will not be set.
283 	 */
284 	ret->flags = optack->MGMT_flags & ~req->flags;
285 
286 	/*
287 	 * NOTE:
288 	 * There is no real change of state in state table for option
289 	 * management. The state change macro is used below only for its
290 	 * debugging and logging capabilities.
291 	 * The TLI "(mis)feature" (option management only in T_IDLE state)
292 	 * has been deprecated in XTI and our state table reflect updated for
293 	 * both TLI and XTI to reflect that.
294 	 * TLI semantics can be enforced by the transport providers that
295 	 * desire it at TPI level.
296 	 * There is no need to enforce this in the library since
297 	 * sane transport providers that do allow it (e.g TCP and it *needs*
298 	 * to allow it) should be allowed to work fine.
299 	 * The only transport providers that return TOUTSTATE for TLI
300 	 * t_optmgmt() are the drivers used for conformance testing to the
301 	 * broken TLI standard.
302 	 * These are /dev/{ticots,ticotsord,ticlts} used by the Sparc ABI test
303 	 * suite. Others are /dev/{tivc,tidg} used by the SVVS test suite.
304 	 */
305 
306 	_T_TX_NEXTSTATE(T_OPTMGMT, tiptr,
307 	    "t_optmgmt: invalid state event T_OPTMGMT");
308 
309 	if (didalloc)
310 		free(ctlbuf.buf);
311 	else
312 		tiptr->ti_ctlbuf = ctlbuf.buf;
313 	sig_mutex_unlock(&tiptr->ti_lock);
314 	(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
315 	return (0);
316 	/* NOTREACHED */
317 
318 err_out:
319 	sv_errno = errno;
320 	if (didalloc)
321 		free(ctlbuf.buf);
322 	else
323 		tiptr->ti_ctlbuf = ctlbuf.buf;
324 	sig_mutex_unlock(&tiptr->ti_lock);
325 	(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
326 	errno = sv_errno;
327 	return (-1);
328 }
329