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 2006 Sun Microsystems, Inc.  All rights reserved.
28 * Use is subject to license terms.
29 */
30
31#pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SVr4.0 1.5.2.1 */
32
33#include "mt.h"
34#include <stdlib.h>
35#include <errno.h>
36#include <unistd.h>
37#include <stropts.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 <assert.h>
46#include "tx.h"
47
48int
49_tx_accept(
50	int fd,
51	int resfd,
52	const struct t_call *call,
53	int api_semantics
54)
55{
56	struct T_conn_res *cres;
57	struct strfdinsert strfdinsert;
58	int size, retval, sv_errno;
59	struct _ti_user *tiptr;
60	struct _ti_user *restiptr;
61	sigset_t mask;
62	struct strbuf ctlbuf;
63	int didalloc;
64	t_scalar_t conn_res_prim;
65
66	if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL)
67		return (-1);
68	if ((restiptr = _t_checkfd(resfd, 0, api_semantics)) == NULL)
69		return (-1);
70
71	/*
72	 * We need to block signals to perform the I_FDINSERT operation
73	 * (sending T_CONN_RES downstream) which is non-idempotent.
74	 * Note that sig_mutex_lock() only defers signals, it does not
75	 * block them, so interruptible syscalls could still get EINTR.
76	 */
77	(void) thr_sigsetmask(SIG_SETMASK, &fillset, &mask);
78	sig_mutex_lock(&tiptr->ti_lock);
79
80	if (tiptr->ti_servtype == T_CLTS) {
81		t_errno = TNOTSUPPORT;
82		sig_mutex_unlock(&tiptr->ti_lock);
83		(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
84		return (-1);
85	}
86
87	if (_T_IS_XTI(api_semantics)) {
88		/*
89		 * User level state verification only done for XTI
90		 * because doing for TLI may break existing applications
91		 *
92		 * For fd == resfd, state should be T_INCON
93		 * For fd != resfd,
94		 *	    fd state should be T_INCON
95		 *	    resfd state should be T_IDLE (bound endpoint) or
96		 *	    it can be T_UNBND. The T_UNBND case is not (yet?)
97		 *	    allowed in the published XTI spec but fixed by the
98		 *	    corrigenda.
99		 */
100		if ((fd == resfd && tiptr->ti_state != T_INCON) ||
101		    (fd != resfd &&
102			((tiptr->ti_state != T_INCON) ||
103		    !(restiptr->ti_state == T_IDLE ||
104			restiptr->ti_state == T_UNBND)))) {
105			t_errno = TOUTSTATE;
106			sig_mutex_unlock(&tiptr->ti_lock);
107			(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
108			return (-1);
109		}
110
111		/*
112		 * XTI says:
113		 * If fd != resfd, and a resfd bound to a protocol address is
114		 * passed, then it better not have a qlen > 0.
115		 * That is, an endpoint bound as if it will be a listener
116		 * cannot be used as an acceptor.
117		 */
118		if (fd != resfd && restiptr->ti_state == T_IDLE &&
119		    restiptr->ti_qlen > 0) {
120			t_errno = TRESQLEN;
121			sig_mutex_unlock(&tiptr->ti_lock);
122			(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
123			return (-1);
124		}
125
126		if (fd == resfd && tiptr->ti_ocnt > 1) {
127			t_errno = TINDOUT;
128			sig_mutex_unlock(&tiptr->ti_lock);
129			(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
130			return (-1);
131		}
132
133		/*
134		 * Note: TRESADDR error is specified by XTI. It happens
135		 * when resfd is bound and fd and resfd are not BOUND to
136		 * the same protocol address. TCP obviously does allow
137		 * two endpoints to bind to the same address. Why is the
138		 * need for this error considering there is an address switch
139		 * that can be done for the endpoint at accept time ? Go
140		 * figure and ask the XTI folks.
141		 * We interpret this to be a transport specific error condition
142		 * to be be coveyed by the transport provider in T_ERROR_ACK
143		 * to T_CONN_RES on transports that allow two endpoints to
144		 * be bound to the same address and have trouble with the
145		 * idea of accepting connections on a resfd that has a qlen > 0
146		 */
147	}
148
149	if (fd != resfd) {
150		if ((retval = ioctl(resfd, I_NREAD, &size)) < 0) {
151			sv_errno = errno;
152
153			t_errno = TSYSERR;
154			sig_mutex_unlock(&tiptr->ti_lock);
155			(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
156			errno = sv_errno;
157			return (-1);
158		}
159		if (retval > 0) {
160			t_errno = TBADF;
161			sig_mutex_unlock(&tiptr->ti_lock);
162			(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
163			return (-1);
164		}
165	}
166
167	/*
168	 * Acquire ctlbuf for use in sending/receiving control part
169	 * of the message.
170	 */
171	if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) {
172		sv_errno = errno;
173		sig_mutex_unlock(&tiptr->ti_lock);
174		(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
175		errno = sv_errno;
176		return (-1);
177	}
178
179	/*
180	 * In Unix98 t_accept() need not return [TLOOK] if connect/disconnect
181	 * indications are present. TLI and Unix95 need to return error.
182	 */
183	if (_T_API_VER_LT(api_semantics, TX_XTI_XNS5_API)) {
184		if (_t_is_event(fd, tiptr) < 0)
185			goto err_out;
186	}
187
188	/* LINTED pointer cast */
189	cres = (struct T_conn_res *)ctlbuf.buf;
190	cres->OPT_length = call->opt.len;
191	cres->OPT_offset = 0;
192	cres->SEQ_number = call->sequence;
193	if ((restiptr->ti_flags & V_ACCEPTOR_ID) != 0) {
194		cres->ACCEPTOR_id = restiptr->acceptor_id;
195		cres->PRIM_type = conn_res_prim = T_CONN_RES;
196	} else {
197		/* I_FDINSERT should use O_T_CONN_RES. */
198		cres->ACCEPTOR_id = 0;
199		cres->PRIM_type = conn_res_prim = O_T_CONN_RES;
200	}
201
202	size = (int)sizeof (struct T_conn_res);
203
204	if (call->opt.len) {
205		if (_t_aligned_copy(&ctlbuf, call->opt.len, size,
206		    call->opt.buf, &cres->OPT_offset) < 0) {
207			/*
208			 * Aligned copy will overflow buffer allocated based
209			 * transport maximum options length.
210			 * return error.
211			 */
212			t_errno = TBADOPT;
213			goto err_out;
214		}
215		size = cres->OPT_offset + cres->OPT_length;
216	}
217
218	if (call->udata.len) {
219		if ((tiptr->ti_cdatasize == T_INVALID /* -2 */) ||
220		    ((tiptr->ti_cdatasize != T_INFINITE /* -1 */) &&
221			(call->udata.len > (uint32_t)tiptr->ti_cdatasize))) {
222			/*
223			 * user data not valid with connect or it
224			 * exceeds the limits specified by the transport
225			 * provider
226			 */
227			t_errno = TBADDATA;
228			goto err_out;
229		}
230	}
231
232
233	ctlbuf.len = size;
234
235	/*
236	 * Assumes signals are blocked so putmsg() will not block
237	 * indefinitely
238	 */
239	if ((restiptr->ti_flags & V_ACCEPTOR_ID) != 0) {
240		/*
241		 * Assumes signals are blocked so putmsg() will not block
242		 * indefinitely
243		 */
244		if (putmsg(fd, &ctlbuf,
245		    (struct strbuf *)(call->udata.len? &call->udata: NULL), 0) <
246		    0) {
247			if (errno == EAGAIN)
248				t_errno = TFLOW;
249			else
250				t_errno = TSYSERR;
251			goto err_out;
252		}
253	} else {
254		strfdinsert.ctlbuf.maxlen = ctlbuf.maxlen;
255		strfdinsert.ctlbuf.len = ctlbuf.len;
256		strfdinsert.ctlbuf.buf = ctlbuf.buf;
257
258		strfdinsert.databuf.maxlen = call->udata.maxlen;
259		strfdinsert.databuf.len =
260		    (call->udata.len? call->udata.len: -1);
261		strfdinsert.databuf.buf = call->udata.buf;
262		strfdinsert.fildes = resfd;
263		strfdinsert.offset = (int)sizeof (t_scalar_t);
264		strfdinsert.flags = 0;		/* could be EXPEDITED also */
265
266		if (ioctl(fd, I_FDINSERT, &strfdinsert) < 0) {
267			if (errno == EAGAIN)
268				t_errno = TFLOW;
269			else
270				t_errno = TSYSERR;
271			goto err_out;
272		}
273	}
274
275	if (_t_is_ok(fd, tiptr, conn_res_prim) < 0) {
276		/*
277		 * At the TPI level, the error returned in a T_ERROR_ACK
278		 * received in response to a T_CONN_RES for a listener and
279		 * acceptor endpoints not being the same kind of endpoints
280		 * has changed to a new t_errno code introduced with
281		 * XTI (TPROVMISMATCH). We need to adjust TLI error code
282		 * to be same as before.
283		 */
284		if (_T_IS_TLI(api_semantics) && t_errno == TPROVMISMATCH) {
285			/* TLI only */
286			t_errno = TBADF;
287		}
288		goto err_out;
289	}
290
291	if (tiptr->ti_ocnt == 1) {
292		if (fd == resfd) {
293			_T_TX_NEXTSTATE(T_ACCEPT1, tiptr,
294				"t_accept: invalid state event T_ACCEPT1");
295		} else {
296			_T_TX_NEXTSTATE(T_ACCEPT2, tiptr,
297				"t_accept: invalid state event T_ACCEPT2");
298			/*
299			 * XXX Here we lock the resfd lock also. This
300			 * is an instance of holding two locks without
301			 * any enforcement of a locking hiararchy.
302			 * There is potential for deadlock in incorrect
303			 * or buggy programs here but this is the safer
304			 * choice in this case. Correct programs will not
305			 * deadlock.
306			 */
307			sig_mutex_lock(&restiptr->ti_lock);
308			_T_TX_NEXTSTATE(T_PASSCON, restiptr,
309				"t_accept: invalid state event T_PASSCON");
310			sig_mutex_unlock(&restiptr->ti_lock);
311		}
312	} else {
313		_T_TX_NEXTSTATE(T_ACCEPT3, tiptr,
314				"t_accept: invalid state event T_ACCEPT3");
315		if (fd != resfd)
316			sig_mutex_lock(&restiptr->ti_lock);
317		_T_TX_NEXTSTATE(T_PASSCON, restiptr,
318				"t_accept: invalid state event T_PASSCON");
319		if (fd != resfd)
320			sig_mutex_unlock(&restiptr->ti_lock);
321	}
322
323	tiptr->ti_ocnt--;
324	tiptr->ti_flags &= ~TX_TQFULL_NOTIFIED;
325
326	/*
327	 * Update attributes which may have been negotiated during
328	 * connection establishment for protocols where we suspect
329	 * such negotiation is likely (e.g. OSI). We do not do it for
330	 * all endpoints for performance reasons. Also, this code is
331	 * deliberately done after user level state changes so even
332	 * the (unlikely) failure case reflects a connected endpoint.
333	 */
334	if (restiptr->ti_tsdusize != 0) {
335		if (_t_do_postconn_sync(resfd, restiptr) < 0)
336			goto err_out;
337	}
338
339	if (didalloc)
340		free(ctlbuf.buf);
341	else
342		tiptr->ti_ctlbuf = ctlbuf.buf;
343	sig_mutex_unlock(&tiptr->ti_lock);
344	(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
345	return (0);
346	/* NOTREACHED */
347err_out:
348	sv_errno = errno;
349	if (didalloc)
350		free(ctlbuf.buf);
351	else
352		tiptr->ti_ctlbuf = ctlbuf.buf;
353	sig_mutex_unlock(&tiptr->ti_lock);
354	(void) thr_sigsetmask(SIG_SETMASK, &mask, NULL);
355	errno = sv_errno;
356	return (-1);
357}
358