xref: /illumos-gate/usr/src/lib/libnsl/nsl/t_optmgmt.c (revision 61961e0f)
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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
32 
33 #include "mt.h"
34 #include <stdlib.h>
35 #include <stdio.h>
36 #include <string.h>
37 #include <errno.h>
38 #include <sys/stream.h>
39 #define	_SUN_TPI_VERSION 2
40 #include <sys/tihdr.h>
41 #include <sys/timod.h>
42 #include <xti.h>
43 #include <signal.h>
44 #include <syslog.h>
45 #include <stropts.h>
46 #include "tx.h"
47 
48 /*
49  * The following is based on XTI standard.
50  */
51 #define	ALIGN_XTI_opthdr_size	(sizeof (t_uscalar_t))
52 
53 #define	ROUNDUP_XTI_opthdr(p)	(((p) +\
54 		(ALIGN_XTI_opthdr_size-1)) & ~(ALIGN_XTI_opthdr_size-1))
55 #define	ISALIGNED_XTI_opthdr(p)	\
56 	(((ulong_t)(p) & (ALIGN_XTI_opthdr_size - 1)) == 0)
57 
58 int
59 _tx_optmgmt(
60 	int fd,
61 	const struct t_optmgmt *req,
62 	struct t_optmgmt *ret,
63 	int api_semantics
64 )
65 {
66 	int size, sv_errno;
67 	struct strbuf ctlbuf;
68 	struct T_optmgmt_req *optreq;
69 	struct T_optmgmt_ack *optack;
70 	struct _ti_user *tiptr;
71 	sigset_t mask;
72 	int didalloc, retlen;
73 	struct t_opthdr *opt, *next_opt;
74 	struct t_opthdr *opt_start, *opt_end;
75 	t_uscalar_t first_opt_level;
76 	t_scalar_t optlen;
77 
78 	if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL)
79 		return (-1);
80 
81 	/*
82 	 * We block all signals during the TI_OPTMGMT operation
83 	 * as option change being done could potentially be a
84 	 * non-idempotent operation.
85 	 * Note that sig_mutex_lock() only defers signals, it does not
86 	 * block them, so interruptible syscalls could still get EINTR.
87 	 */
88 	(void) thr_sigsetmask(SIG_SETMASK, &fillset, &mask);
89 	sig_mutex_lock(&tiptr->ti_lock);
90 
91 	/*
92 	 * Acquire buf for use in sending/receiving of the message.
93 	 * Note: assumes (correctly) that ti_ctlsize is large enough
94 	 * to hold sizeof (struct T_bind_req)
95 	 */
96 	if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) {
97 		sv_errno = errno;
98 		sig_mutex_unlock(&tiptr->ti_lock);
99 		(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
100 		errno = sv_errno;
101 		return (-1);
102 	}
103 
104 	/*
105 	 * effective option length in local variable "optlen"
106 	 * Note: can change for XTI for T_ALLOPT. XTI spec states
107 	 * that options after the T_ALLOPT option are to be ignored
108 	 * therefore we trncate the option buffer there and modify
109 	 * the effective length accordingly later.
110 	 */
111 	optlen = req->opt.len;
112 
113 	if (_T_IS_XTI(api_semantics) && (optlen > 0)) {
114 		/*
115 		 * Verify integrity of option buffer according to
116 		 * XTI t_optmgmt() semantics.
117 		 */
118 
119 		if (req->opt.buf == NULL ||
120 		    optlen < (t_scalar_t)sizeof (struct t_opthdr)) {
121 			/* option buffer should atleast have an t_opthdr */
122 			t_errno = TBADOPT;
123 			goto err_out;
124 		}
125 
126 		/* LINTED pointer cast */
127 		opt_start = (struct t_opthdr *)req->opt.buf;
128 
129 		/*
130 		 * XXX We interpret that an option has to start on an
131 		 * aligned buffer boundary. This is not very explcit in
132 		 * XTI spec in text but the picture in Section 6.2 shows
133 		 * "opt.buf" at start of buffer and in combination with
134 		 * text can be construed to be restricting it to start
135 		 * on an aligned boundary. [Whether similar restriction
136 		 * applies to output buffer "ret->opt.buf" is an "interesting
137 		 * question" but we ignore it for now as that is the problem
138 		 * for the application not our implementation which will
139 		 * does not enforce any alignment requirement.]
140 		 *
141 		 * If start of buffer is not aligned, we signal an error.
142 		 */
143 		if (!(ISALIGNED_XTI_opthdr(opt_start))) {
144 			t_errno = TBADOPT;
145 			goto err_out;
146 		}
147 
148 		/* LINTED pointer cast */
149 		opt_end = (struct t_opthdr *)((char *)opt_start +
150 						optlen);
151 
152 		/*
153 		 * Make sure we have enough in the message to dereference
154 		 * the option header.
155 		 */
156 		if ((uchar_t *)opt_start + sizeof (struct t_opthdr)
157 		    > (uchar_t *)opt_end) {
158 			t_errno = TBADOPT;
159 			goto err_out;
160 		}
161 		/*
162 		 * If there are multiple options, they all have to be
163 		 * the same level (so says XTI semantics).
164 		 */
165 		first_opt_level = opt_start->level;
166 
167 		for (opt = opt_start; opt < opt_end; opt = next_opt) {
168 			/*
169 			 * Make sure we have enough in the message to
170 			 * dereference the option header.
171 			 */
172 			if ((uchar_t *)opt_start + sizeof (struct t_opthdr)
173 			    > (uchar_t *)opt_end) {
174 				t_errno = TBADOPT;
175 				goto err_out;
176 			}
177 			/*
178 			 * We now compute pointer to next option in buffer
179 			 * 'next_opt' the next_opt computation above below
180 			 * 'opt->len' initialized by application which cannot
181 			 * be trusted. The usual value too large will be
182 			 * captured by the loop termination condition above.
183 			 * We check for the following which it will miss.
184 			 *	(1)pointer space wraparound arithmetic overflow
185 			 *	(2)last option in buffer with 'opt->len' being
186 			 *	  too large
187 			 *	(only reason 'next_opt' should equal or exceed
188 			 *	'opt_end' for last option is roundup unless
189 			 *	length is too-large/invalid)
190 			 *	(3) we also enforce the XTI restriction that
191 			 *	   all options in the buffer have to be the
192 			 *	   same level.
193 			 */
194 			/* LINTED pointer cast */
195 			next_opt = (struct t_opthdr *)((uchar_t *)opt +
196 			    ROUNDUP_XTI_opthdr(opt->len));
197 
198 			if ((uchar_t *)next_opt < (uchar_t *)opt || /* (1) */
199 			    ((next_opt >= opt_end) &&
200 				(((uchar_t *)next_opt - (uchar_t *)opt_end) >=
201 				    ALIGN_XTI_opthdr_size)) || /* (2) */
202 			    (opt->level != first_opt_level)) { /* (3) */
203 				t_errno = TBADOPT;
204 				goto err_out;
205 			}
206 
207 			/*
208 			 * XTI semantics: options in the buffer after
209 			 * the T_ALLOPT option can be ignored
210 			 */
211 			if (opt->name == T_ALLOPT) {
212 				if (next_opt < opt_end) {
213 					/*
214 					 * there are options following, ignore
215 					 * them and truncate input
216 					 */
217 					optlen = (t_scalar_t)((uchar_t *)
218 					    next_opt - (uchar_t *)opt_start);
219 					opt_end = next_opt;
220 				}
221 			}
222 		}
223 	}
224 
225 	/* LINTED pointer cast */
226 	optreq = (struct T_optmgmt_req *)ctlbuf.buf;
227 	if (_T_IS_XTI(api_semantics))
228 		optreq->PRIM_type = T_OPTMGMT_REQ;
229 	else
230 		optreq->PRIM_type = T_SVR4_OPTMGMT_REQ;
231 
232 	optreq->OPT_length = optlen;
233 	optreq->OPT_offset = 0;
234 	optreq->MGMT_flags = req->flags;
235 	size = (int)sizeof (struct T_optmgmt_req);
236 
237 	if (optlen) {
238 		if (_t_aligned_copy(&ctlbuf, optlen, size,
239 		    req->opt.buf, &optreq->OPT_offset) < 0) {
240 			/*
241 			 * Aligned copy will overflow buffer allocated
242 			 * based on maximum transport option size information
243 			 */
244 			t_errno = TBADOPT;
245 			goto err_out;
246 		}
247 		size = optreq->OPT_offset + optreq->OPT_length;
248 	}
249 
250 	if (_t_do_ioctl(fd, ctlbuf.buf, size, TI_OPTMGMT, &retlen) < 0)
251 		goto err_out;
252 
253 	if (retlen < (int)sizeof (struct T_optmgmt_ack)) {
254 		t_errno = TSYSERR;
255 		errno = EIO;
256 		goto err_out;
257 	}
258 
259 	/* LINTED pointer cast */
260 	optack = (struct T_optmgmt_ack *)ctlbuf.buf;
261 
262 	if (_T_IS_TLI(api_semantics) || ret->opt.maxlen > 0) {
263 		if (TLEN_GT_NLEN(optack->OPT_length, ret->opt.maxlen)) {
264 			t_errno = TBUFOVFLW;
265 			goto err_out;
266 		}
267 		(void) memcpy(ret->opt.buf,
268 		    (char *)(ctlbuf.buf + optack->OPT_offset),
269 		    (unsigned int) optack->OPT_length);
270 		ret->opt.len = optack->OPT_length;
271 	}
272 
273 	/*
274 	 * Note: TPI is not clear about what really is carries in the
275 	 * T_OPTMGMT_ACK MGMT_flags fields. For T_OPTMGMT_ACK in response
276 	 * to T_SVR4_OPTMGMT_REQ, the Internet protocols in Solaris 2.X return
277 	 * the result code only (T_SUCCESS). For T_OPTMGMT_ACK in response
278 	 * to T_OPTMGMT_REQ, currently "worst status" code required for
279 	 * XTI is carried from the set of options OR'd with request flag.
280 	 * (This can change in future and "worst status" computation done
281 	 * with a scan in this routine.
282 	 *
283 	 * Note: Even for T_OPTMGMT_ACK is response to T_SVR4_OPTMGMT_REQ,
284 	 * removing request flag should be OK though it will not be set.
285 	 */
286 	ret->flags = optack->MGMT_flags & ~req->flags;
287 
288 	/*
289 	 * NOTE:
290 	 * There is no real change of state in state table for option
291 	 * management. The state change macro is used below only for its
292 	 * debugging and logging capabilities.
293 	 * The TLI "(mis)feature" (option management only in T_IDLE state)
294 	 * has been deprecated in XTI and our state table reflect updated for
295 	 * both TLI and XTI to reflect that.
296 	 * TLI semantics can be enforced by the transport providers that
297 	 * desire it at TPI level.
298 	 * There is no need to enforce this in the library since
299 	 * sane transport providers that do allow it (e.g TCP and it *needs*
300 	 * to allow it) should be allowed to work fine.
301 	 * The only transport providers that return TOUTSTATE for TLI
302 	 * t_optmgmt() are the drivers used for conformance testing to the
303 	 * broken TLI standard.
304 	 * These are /dev/{ticots,ticotsord,ticlts} used by the Sparc ABI test
305 	 * suite. Others are /dev/{tivc,tidg} used by the SVVS test suite.
306 	 */
307 
308 	_T_TX_NEXTSTATE(T_OPTMGMT, tiptr,
309 	    "t_optmgmt: invalid state event T_OPTMGMT");
310 
311 	if (didalloc)
312 		free(ctlbuf.buf);
313 	else
314 		tiptr->ti_ctlbuf = ctlbuf.buf;
315 	sig_mutex_unlock(&tiptr->ti_lock);
316 	(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
317 	return (0);
318 	/* NOTREACHED */
319 
320 err_out:
321 	sv_errno = errno;
322 	if (didalloc)
323 		free(ctlbuf.buf);
324 	else
325 		tiptr->ti_ctlbuf = ctlbuf.buf;
326 	sig_mutex_unlock(&tiptr->ti_lock);
327 	(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
328 	errno = sv_errno;
329 	return (-1);
330 }
331