xref: /netbsd-src/lib/libc/rpc/clnt_vc.c (revision a4ddc2c8fb9af816efe3b1c375a5530aef0e89e9)
1 /*	$NetBSD: clnt_vc.c,v 1.21 2013/03/11 20:19:29 tron Exp $	*/
2 
3 /*
4  * Copyright (c) 2010, Oracle America, Inc.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are
8  * met:
9  *
10  *     * Redistributions of source code must retain the above copyright
11  *       notice, this list of conditions and the following disclaimer.
12  *     * Redistributions in binary form must reproduce the above
13  *       copyright notice, this list of conditions and the following
14  *       disclaimer in the documentation and/or other materials
15  *       provided with the distribution.
16  *     * Neither the name of the "Oracle America, Inc." nor the names of its
17  *       contributors may be used to endorse or promote products derived
18  *       from this software without specific prior written permission.
19  *
20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #if defined(LIBC_SCCS) && !defined(lint)
36 #if 0
37 static char *sccsid = "@(#)clnt_tcp.c 1.37 87/10/05 Copyr 1984 Sun Micro";
38 static char *sccsid = "@(#)clnt_tcp.c	2.2 88/08/01 4.0 RPCSRC";
39 static char sccsid[] = "@(#)clnt_vc.c 1.19 89/03/16 Copyr 1988 Sun Micro";
40 #else
41 __RCSID("$NetBSD: clnt_vc.c,v 1.21 2013/03/11 20:19:29 tron Exp $");
42 #endif
43 #endif
44 
45 /*
46  * clnt_tcp.c, Implements a TCP/IP based, client side RPC.
47  *
48  * Copyright (C) 1984, Sun Microsystems, Inc.
49  *
50  * TCP based RPC supports 'batched calls'.
51  * A sequence of calls may be batched-up in a send buffer.  The rpc call
52  * return immediately to the client even though the call was not necessarily
53  * sent.  The batching occurs if the results' xdr routine is NULL (0) AND
54  * the rpc timeout value is zero (see clnt.h, rpc).
55  *
56  * Clients should NOT casually batch calls that in fact return results; that is,
57  * the server side should be aware that a call is batched and not produce any
58  * return message.  Batched calls that produce many result messages can
59  * deadlock (netlock) the client and the server....
60  *
61  * Now go hang yourself.
62  */
63 
64 #include "namespace.h"
65 #include "reentrant.h"
66 #include <sys/types.h>
67 #include <sys/poll.h>
68 #include <sys/socket.h>
69 
70 #include <assert.h>
71 #include <err.h>
72 #include <errno.h>
73 #include <netdb.h>
74 #include <stdio.h>
75 #include <stdlib.h>
76 #include <string.h>
77 #include <unistd.h>
78 #include <signal.h>
79 
80 #include <rpc/rpc.h>
81 
82 #include "svc_fdset.h"
83 #include "rpc_internal.h"
84 
85 #ifdef __weak_alias
86 __weak_alias(clnt_vc_create,_clnt_vc_create)
87 #endif
88 
89 #define MCALL_MSG_SIZE 24
90 
91 static enum clnt_stat clnt_vc_call(CLIENT *, rpcproc_t, xdrproc_t,
92     const char *, xdrproc_t, caddr_t, struct timeval);
93 static void clnt_vc_geterr(CLIENT *, struct rpc_err *);
94 static bool_t clnt_vc_freeres(CLIENT *, xdrproc_t, caddr_t);
95 static void clnt_vc_abort(CLIENT *);
96 static bool_t clnt_vc_control(CLIENT *, u_int, char *);
97 static void clnt_vc_destroy(CLIENT *);
98 static struct clnt_ops *clnt_vc_ops(void);
99 static bool_t time_not_ok(struct timeval *);
100 static int read_vc(caddr_t, caddr_t, int);
101 static int write_vc(caddr_t, caddr_t, int);
102 
103 struct ct_data {
104 	int		ct_fd;
105 	bool_t		ct_closeit;
106 	struct timeval	ct_wait;
107 	bool_t          ct_waitset;       /* wait set by clnt_control? */
108 	struct netbuf	ct_addr;
109 	struct rpc_err	ct_error;
110 	union {
111 		char	ct_mcallc[MCALL_MSG_SIZE];	/* marshalled callmsg */
112 		u_int32_t ct_mcalli;
113 	} ct_u;
114 	u_int		ct_mpos;			/* pos after marshal */
115 	XDR		ct_xdrs;
116 };
117 
118 /*
119  *      This machinery implements per-fd locks for MT-safety.  It is not
120  *      sufficient to do per-CLIENT handle locks for MT-safety because a
121  *      user may create more than one CLIENT handle with the same fd behind
122  *      it.  Therfore, we allocate an array of flags (vc_fd_locks), protected
123  *      by the clnt_fd_lock mutex, and an array (vc_cv) of condition variables
124  *      similarly protected.  Vc_fd_lock[fd] == 1 => a call is activte on some
125  *      CLIENT handle created for that fd.
126  *      The current implementation holds locks across the entire RPC and reply.
127  *      Yes, this is silly, and as soon as this code is proven to work, this
128  *      should be the first thing fixed.  One step at a time.
129  */
130 #ifdef _REENTRANT
131 static int      *vc_fd_locks;
132 #define __rpc_lock_value __isthreaded;
133 extern mutex_t  clnt_fd_lock;
134 static cond_t   *vc_cv;
135 #define release_fd_lock(fd, mask) {             \
136 	mutex_lock(&clnt_fd_lock);      \
137 	vc_fd_locks[fd] = 0;            \
138 	mutex_unlock(&clnt_fd_lock);    \
139 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);        \
140 	cond_signal(&vc_cv[fd]);        \
141 }
142 #else
143 #define release_fd_lock(fd,mask)
144 #define __rpc_lock_value 0
145 #endif
146 
147 
148 /*
149  * Create a client handle for a connection.
150  * Default options are set, which the user can change using clnt_control()'s.
151  * The rpc/vc package does buffering similar to stdio, so the client
152  * must pick send and receive buffer sizes, 0 => use the default.
153  * NB: fd is copied into a private area.
154  * NB: The rpch->cl_auth is set null authentication. Caller may wish to
155  * set this something more useful.
156  *
157  * fd should be an open socket
158  */
159 CLIENT *
160 clnt_vc_create(
161 	int fd,
162 	const struct netbuf *raddr,
163 	rpcprog_t prog,
164 	rpcvers_t vers,
165 	u_int sendsz,
166 	u_int recvsz
167 )
168 {
169 	CLIENT *h;
170 	struct ct_data *ct = NULL;
171 	struct rpc_msg call_msg;
172 #ifdef _REENTRANT
173 	sigset_t mask;
174 #endif
175 	sigset_t newmask;
176 	struct sockaddr_storage ss;
177 	socklen_t slen;
178 	struct __rpc_sockinfo si;
179 
180 	_DIAGASSERT(raddr != NULL);
181 
182 	h  = mem_alloc(sizeof(*h));
183 	if (h == NULL) {
184 		warnx("clnt_vc_create: out of memory");
185 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
186 		rpc_createerr.cf_error.re_errno = errno;
187 		goto fooy;
188 	}
189 	ct = mem_alloc(sizeof(*ct));
190 	if (ct == NULL) {
191 		warnx("clnt_vc_create: out of memory");
192 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
193 		rpc_createerr.cf_error.re_errno = errno;
194 		goto fooy;
195 	}
196 
197 	sigfillset(&newmask);
198 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
199 #ifdef _REENTRANT
200 	mutex_lock(&clnt_fd_lock);
201 	if (vc_fd_locks == NULL) {
202 		size_t cv_allocsz, fd_allocsz;
203 		int dtbsize = __rpc_dtbsize();
204 
205 		fd_allocsz = dtbsize * sizeof (int);
206 		vc_fd_locks = mem_alloc(fd_allocsz);
207 		if (vc_fd_locks == NULL) {
208 			mutex_unlock(&clnt_fd_lock);
209 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
210 			goto fooy;
211 		} else
212 			memset(vc_fd_locks, '\0', fd_allocsz);
213 
214 		_DIAGASSERT(vc_cv == NULL);
215 		cv_allocsz = dtbsize * sizeof (cond_t);
216 		vc_cv = mem_alloc(cv_allocsz);
217 		if (vc_cv == NULL) {
218 			mem_free(vc_fd_locks, fd_allocsz);
219 			vc_fd_locks = NULL;
220 			mutex_unlock(&clnt_fd_lock);
221 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
222 			goto fooy;
223 		} else {
224 			int i;
225 
226 			for (i = 0; i < dtbsize; i++)
227 				cond_init(&vc_cv[i], 0, (void *) 0);
228 		}
229 	} else
230 		_DIAGASSERT(vc_cv != NULL);
231 #endif
232 
233 	/*
234 	 * XXX - fvdl connecting while holding a mutex?
235 	 */
236 	slen = sizeof ss;
237 	if (getpeername(fd, (struct sockaddr *)(void *)&ss, &slen) < 0) {
238 		if (errno != ENOTCONN) {
239 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
240 			rpc_createerr.cf_error.re_errno = errno;
241 			mutex_unlock(&clnt_fd_lock);
242 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
243 			goto fooy;
244 		}
245 		if (connect(fd, (struct sockaddr *)raddr->buf, raddr->len) < 0){
246 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
247 			rpc_createerr.cf_error.re_errno = errno;
248 			mutex_unlock(&clnt_fd_lock);
249 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
250 			goto fooy;
251 		}
252 	}
253 	mutex_unlock(&clnt_fd_lock);
254 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
255 	if (!__rpc_fd2sockinfo(fd, &si))
256 		goto fooy;
257 
258 	ct->ct_closeit = FALSE;
259 
260 	/*
261 	 * Set up private data struct
262 	 */
263 	ct->ct_fd = fd;
264 	ct->ct_wait.tv_usec = 0;
265 	ct->ct_waitset = FALSE;
266 	ct->ct_addr.buf = malloc((size_t)raddr->maxlen);
267 	if (ct->ct_addr.buf == NULL)
268 		goto fooy;
269 	memcpy(ct->ct_addr.buf, raddr->buf, (size_t)raddr->len);
270 	ct->ct_addr.len = raddr->len;
271 	ct->ct_addr.maxlen = raddr->maxlen;
272 
273 	/*
274 	 * Initialize call message
275 	 */
276 	call_msg.rm_xid = __RPC_GETXID();
277 	call_msg.rm_direction = CALL;
278 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
279 	call_msg.rm_call.cb_prog = (u_int32_t)prog;
280 	call_msg.rm_call.cb_vers = (u_int32_t)vers;
281 
282 	/*
283 	 * pre-serialize the static part of the call msg and stash it away
284 	 */
285 	xdrmem_create(&(ct->ct_xdrs), ct->ct_u.ct_mcallc, MCALL_MSG_SIZE,
286 	    XDR_ENCODE);
287 	if (! xdr_callhdr(&(ct->ct_xdrs), &call_msg)) {
288 		if (ct->ct_closeit) {
289 			(void)close(fd);
290 		}
291 		goto fooy;
292 	}
293 	ct->ct_mpos = XDR_GETPOS(&(ct->ct_xdrs));
294 	XDR_DESTROY(&(ct->ct_xdrs));
295 
296 	/*
297 	 * Create a client handle which uses xdrrec for serialization
298 	 * and authnone for authentication.
299 	 */
300 	h->cl_ops = clnt_vc_ops();
301 	h->cl_private = ct;
302 	h->cl_auth = authnone_create();
303 	sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
304 	recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
305 	xdrrec_create(&(ct->ct_xdrs), sendsz, recvsz,
306 	    h->cl_private, read_vc, write_vc);
307 	return (h);
308 
309 fooy:
310 	/*
311 	 * Something goofed, free stuff and barf
312 	 */
313 	if (ct)
314 		mem_free(ct, sizeof(struct ct_data));
315 	if (h)
316 		mem_free(h, sizeof(CLIENT));
317 	return (NULL);
318 }
319 
320 static enum clnt_stat
321 clnt_vc_call(
322 	CLIENT *h,
323 	rpcproc_t proc,
324 	xdrproc_t xdr_args,
325 	const char *args_ptr,
326 	xdrproc_t xdr_results,
327 	caddr_t results_ptr,
328 	struct timeval timeout
329 )
330 {
331 	struct ct_data *ct;
332 	XDR *xdrs;
333 	struct rpc_msg reply_msg;
334 	u_int32_t x_id;
335 	u_int32_t *msg_x_id;
336 	bool_t shipnow;
337 	int refreshes = 2;
338 #ifdef _REENTRANT
339 	sigset_t mask, newmask;
340 #endif
341 
342 	_DIAGASSERT(h != NULL);
343 
344 	ct = (struct ct_data *) h->cl_private;
345 
346 #ifdef _REENTRANT
347 	sigfillset(&newmask);
348 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
349 	mutex_lock(&clnt_fd_lock);
350 	while (vc_fd_locks[ct->ct_fd])
351 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
352 	vc_fd_locks[ct->ct_fd] = __rpc_lock_value;
353 	mutex_unlock(&clnt_fd_lock);
354 #endif
355 
356 	xdrs = &(ct->ct_xdrs);
357 	msg_x_id = &ct->ct_u.ct_mcalli;
358 
359 	if (!ct->ct_waitset) {
360 		if (time_not_ok(&timeout) == FALSE)
361 		ct->ct_wait = timeout;
362 	}
363 
364 	shipnow =
365 	    (xdr_results == NULL && timeout.tv_sec == 0
366 	    && timeout.tv_usec == 0) ? FALSE : TRUE;
367 
368 call_again:
369 	xdrs->x_op = XDR_ENCODE;
370 	ct->ct_error.re_status = RPC_SUCCESS;
371 	x_id = ntohl(--(*msg_x_id));
372 	if ((! XDR_PUTBYTES(xdrs, ct->ct_u.ct_mcallc, ct->ct_mpos)) ||
373 	    (! XDR_PUTINT32(xdrs, (int32_t *)&proc)) ||
374 	    (! AUTH_MARSHALL(h->cl_auth, xdrs)) ||
375 	    (! (*xdr_args)(xdrs, __UNCONST(args_ptr)))) {
376 		if (ct->ct_error.re_status == RPC_SUCCESS)
377 			ct->ct_error.re_status = RPC_CANTENCODEARGS;
378 		(void)xdrrec_endofrecord(xdrs, TRUE);
379 		release_fd_lock(ct->ct_fd, mask);
380 		return (ct->ct_error.re_status);
381 	}
382 	if (! xdrrec_endofrecord(xdrs, shipnow)) {
383 		release_fd_lock(ct->ct_fd, mask);
384 		return (ct->ct_error.re_status = RPC_CANTSEND);
385 	}
386 	if (! shipnow) {
387 		release_fd_lock(ct->ct_fd, mask);
388 		return (RPC_SUCCESS);
389 	}
390 	/*
391 	 * Hack to provide rpc-based message passing
392 	 */
393 	if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
394 		release_fd_lock(ct->ct_fd, mask);
395 		return(ct->ct_error.re_status = RPC_TIMEDOUT);
396 	}
397 
398 
399 	/*
400 	 * Keep receiving until we get a valid transaction id
401 	 */
402 	xdrs->x_op = XDR_DECODE;
403 	for (;;) {
404 		reply_msg.acpted_rply.ar_verf = _null_auth;
405 		reply_msg.acpted_rply.ar_results.where = NULL;
406 		reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
407 		if (! xdrrec_skiprecord(xdrs)) {
408 			release_fd_lock(ct->ct_fd, mask);
409 			return (ct->ct_error.re_status);
410 		}
411 		/* now decode and validate the response header */
412 		if (! xdr_replymsg(xdrs, &reply_msg)) {
413 			if (ct->ct_error.re_status == RPC_SUCCESS)
414 				continue;
415 			release_fd_lock(ct->ct_fd, mask);
416 			return (ct->ct_error.re_status);
417 		}
418 		if (reply_msg.rm_xid == x_id)
419 			break;
420 	}
421 
422 	/*
423 	 * process header
424 	 */
425 	_seterr_reply(&reply_msg, &(ct->ct_error));
426 	if (ct->ct_error.re_status == RPC_SUCCESS) {
427 		if (! AUTH_VALIDATE(h->cl_auth,
428 		    &reply_msg.acpted_rply.ar_verf)) {
429 			ct->ct_error.re_status = RPC_AUTHERROR;
430 			ct->ct_error.re_why = AUTH_INVALIDRESP;
431 		} else if (! (*xdr_results)(xdrs, results_ptr)) {
432 			if (ct->ct_error.re_status == RPC_SUCCESS)
433 				ct->ct_error.re_status = RPC_CANTDECODERES;
434 		}
435 		/* free verifier ... */
436 		if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
437 			xdrs->x_op = XDR_FREE;
438 			(void)xdr_opaque_auth(xdrs,
439 			    &(reply_msg.acpted_rply.ar_verf));
440 		}
441 	}  /* end successful completion */
442 	else {
443 		/* maybe our credentials need to be refreshed ... */
444 		if (refreshes-- && AUTH_REFRESH(h->cl_auth))
445 			goto call_again;
446 	}  /* end of unsuccessful completion */
447 	release_fd_lock(ct->ct_fd, mask);
448 	return (ct->ct_error.re_status);
449 }
450 
451 static void
452 clnt_vc_geterr(
453 	CLIENT *h,
454 	struct rpc_err *errp
455 )
456 {
457 	struct ct_data *ct;
458 
459 	_DIAGASSERT(h != NULL);
460 	_DIAGASSERT(errp != NULL);
461 
462 	ct = (struct ct_data *) h->cl_private;
463 	*errp = ct->ct_error;
464 }
465 
466 static bool_t
467 clnt_vc_freeres(
468 	CLIENT *cl,
469 	xdrproc_t xdr_res,
470 	caddr_t res_ptr
471 )
472 {
473 	struct ct_data *ct;
474 	XDR *xdrs;
475 	bool_t dummy;
476 #ifdef _REENTRANT
477 	sigset_t mask;
478 #endif
479 	sigset_t newmask;
480 
481 	_DIAGASSERT(cl != NULL);
482 
483 	ct = (struct ct_data *)cl->cl_private;
484 	xdrs = &(ct->ct_xdrs);
485 
486 	sigfillset(&newmask);
487 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
488 	mutex_lock(&clnt_fd_lock);
489 #ifdef _REENTRANT
490 	while (vc_fd_locks[ct->ct_fd])
491 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
492 #endif
493 
494 	xdrs->x_op = XDR_FREE;
495 	dummy = (*xdr_res)(xdrs, res_ptr);
496 	mutex_unlock(&clnt_fd_lock);
497 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
498 	cond_signal(&vc_cv[ct->ct_fd]);
499 
500 	return dummy;
501 }
502 
503 /*ARGSUSED*/
504 static void
505 clnt_vc_abort(CLIENT *cl)
506 {
507 }
508 
509 static bool_t
510 clnt_vc_control(
511 	CLIENT *cl,
512 	u_int request,
513 	char *info
514 )
515 {
516 	struct ct_data *ct;
517 	void *infop = info;
518 #ifdef _REENTRANT
519 	sigset_t mask;
520 #endif
521 	sigset_t newmask;
522 
523 	_DIAGASSERT(cl != NULL);
524 
525 	ct = (struct ct_data *)cl->cl_private;
526 
527 	sigfillset(&newmask);
528 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
529 	mutex_lock(&clnt_fd_lock);
530 #ifdef _REENTRANT
531 	while (vc_fd_locks[ct->ct_fd])
532 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
533 	vc_fd_locks[ct->ct_fd] = __rpc_lock_value;
534 #endif
535 	mutex_unlock(&clnt_fd_lock);
536 
537 	switch (request) {
538 	case CLSET_FD_CLOSE:
539 		ct->ct_closeit = TRUE;
540 		release_fd_lock(ct->ct_fd, mask);
541 		return (TRUE);
542 	case CLSET_FD_NCLOSE:
543 		ct->ct_closeit = FALSE;
544 		release_fd_lock(ct->ct_fd, mask);
545 		return (TRUE);
546 	default:
547 		break;
548 	}
549 
550 	/* for other requests which use info */
551 	if (info == NULL) {
552 		release_fd_lock(ct->ct_fd, mask);
553 		return (FALSE);
554 	}
555 	switch (request) {
556 	case CLSET_TIMEOUT:
557 		if (time_not_ok((struct timeval *)(void *)info)) {
558 			release_fd_lock(ct->ct_fd, mask);
559 			return (FALSE);
560 		}
561 		ct->ct_wait = *(struct timeval *)infop;
562 		ct->ct_waitset = TRUE;
563 		break;
564 	case CLGET_TIMEOUT:
565 		*(struct timeval *)infop = ct->ct_wait;
566 		break;
567 	case CLGET_SERVER_ADDR:
568 		(void) memcpy(info, ct->ct_addr.buf, (size_t)ct->ct_addr.len);
569 		break;
570 	case CLGET_FD:
571 		*(int *)(void *)info = ct->ct_fd;
572 		break;
573 	case CLGET_SVC_ADDR:
574 		/* The caller should not free this memory area */
575 		*(struct netbuf *)(void *)info = ct->ct_addr;
576 		break;
577 	case CLSET_SVC_ADDR:		/* set to new address */
578 		release_fd_lock(ct->ct_fd, mask);
579 		return (FALSE);
580 	case CLGET_XID:
581 		/*
582 		 * use the knowledge that xid is the
583 		 * first element in the call structure
584 		 * This will get the xid of the PREVIOUS call
585 		 */
586 		*(u_int32_t *)(void *)info =
587 		    ntohl(*(u_int32_t *)(void *)&ct->ct_u.ct_mcalli);
588 		break;
589 	case CLSET_XID:
590 		/* This will set the xid of the NEXT call */
591 		*(u_int32_t *)(void *)&ct->ct_u.ct_mcalli =
592 		    htonl(*((u_int32_t *)(void *)info) + 1);
593 		/* increment by 1 as clnt_vc_call() decrements once */
594 		break;
595 	case CLGET_VERS:
596 		/*
597 		 * This RELIES on the information that, in the call body,
598 		 * the version number field is the fifth field from the
599 		 * begining of the RPC header. MUST be changed if the
600 		 * call_struct is changed
601 		 */
602 		*(u_int32_t *)(void *)info =
603 		    ntohl(*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
604 		    4 * BYTES_PER_XDR_UNIT));
605 		break;
606 
607 	case CLSET_VERS:
608 		*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
609 		    4 * BYTES_PER_XDR_UNIT) =
610 		    htonl(*(u_int32_t *)(void *)info);
611 		break;
612 
613 	case CLGET_PROG:
614 		/*
615 		 * This RELIES on the information that, in the call body,
616 		 * the program number field is the fourth field from the
617 		 * begining of the RPC header. MUST be changed if the
618 		 * call_struct is changed
619 		 */
620 		*(u_int32_t *)(void *)info =
621 		    ntohl(*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
622 		    3 * BYTES_PER_XDR_UNIT));
623 		break;
624 
625 	case CLSET_PROG:
626 		*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
627 		    3 * BYTES_PER_XDR_UNIT) =
628 		    htonl(*(u_int32_t *)(void *)info);
629 		break;
630 
631 	default:
632 		release_fd_lock(ct->ct_fd, mask);
633 		return (FALSE);
634 	}
635 	release_fd_lock(ct->ct_fd, mask);
636 	return (TRUE);
637 }
638 
639 
640 static void
641 clnt_vc_destroy(CLIENT *cl)
642 {
643 	struct ct_data *ct;
644 #ifdef _REENTRANT
645 	int ct_fd;
646 	sigset_t mask;
647 #endif
648 	sigset_t newmask;
649 
650 	_DIAGASSERT(cl != NULL);
651 
652 	ct = (struct ct_data *) cl->cl_private;
653 	ct_fd = ct->ct_fd;
654 
655 	sigfillset(&newmask);
656 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
657 	mutex_lock(&clnt_fd_lock);
658 #ifdef _REENTRANT
659 	while (vc_fd_locks[ct_fd])
660 		cond_wait(&vc_cv[ct_fd], &clnt_fd_lock);
661 #endif
662 	if (ct->ct_closeit && ct->ct_fd != -1) {
663 		(void)close(ct->ct_fd);
664 	}
665 	XDR_DESTROY(&(ct->ct_xdrs));
666 	if (ct->ct_addr.buf)
667 		free(ct->ct_addr.buf);
668 	mem_free(ct, sizeof(struct ct_data));
669 	mem_free(cl, sizeof(CLIENT));
670 	mutex_unlock(&clnt_fd_lock);
671 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
672 
673 	cond_signal(&vc_cv[ct_fd]);
674 }
675 
676 /*
677  * Interface between xdr serializer and tcp connection.
678  * Behaves like the system calls, read & write, but keeps some error state
679  * around for the rpc level.
680  */
681 static int
682 read_vc(char *ctp, char *buf, int len)
683 {
684 	struct ct_data *ct = (struct ct_data *)(void *)ctp;
685 	struct pollfd fd;
686 	struct timespec ts;
687 	ssize_t nread;
688 
689 	if (len == 0)
690 		return (0);
691 
692 	TIMEVAL_TO_TIMESPEC(&ct->ct_wait, &ts);
693 	fd.fd = ct->ct_fd;
694 	fd.events = POLLIN;
695 	for (;;) {
696 		switch (pollts(&fd, 1, &ts, NULL)) {
697 		case 0:
698 			ct->ct_error.re_status = RPC_TIMEDOUT;
699 			return (-1);
700 
701 		case -1:
702 			if (errno == EINTR)
703 				continue;
704 			ct->ct_error.re_status = RPC_CANTRECV;
705 			ct->ct_error.re_errno = errno;
706 			return (-1);
707 		}
708 		break;
709 	}
710 	switch (nread = read(ct->ct_fd, buf, (size_t)len)) {
711 
712 	case 0:
713 		/* premature eof */
714 		ct->ct_error.re_errno = ECONNRESET;
715 		ct->ct_error.re_status = RPC_CANTRECV;
716 		len = -1;  /* it's really an error */
717 		break;
718 
719 	case -1:
720 		ct->ct_error.re_errno = errno;
721 		ct->ct_error.re_status = RPC_CANTRECV;
722 		break;
723 	}
724 	return (int)nread;
725 }
726 
727 static int
728 write_vc(char *ctp, char *buf, int len)
729 {
730 	struct ct_data *ct = (struct ct_data *)(void *)ctp;
731 	ssize_t i;
732 	size_t cnt;
733 
734 	for (cnt = len; cnt > 0; cnt -= i, buf += i) {
735 		if ((i = write(ct->ct_fd, buf, cnt)) == -1) {
736 			ct->ct_error.re_errno = errno;
737 			ct->ct_error.re_status = RPC_CANTSEND;
738 			return (-1);
739 		}
740 	}
741 	return len;
742 }
743 
744 static struct clnt_ops *
745 clnt_vc_ops(void)
746 {
747 	static struct clnt_ops ops;
748 #ifdef _REENTRANT
749 	extern mutex_t  ops_lock;
750 	sigset_t mask;
751 #endif
752 	sigset_t newmask;
753 
754 	/* VARIABLES PROTECTED BY ops_lock: ops */
755 
756 	sigfillset(&newmask);
757 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
758 	mutex_lock(&ops_lock);
759 	if (ops.cl_call == NULL) {
760 		ops.cl_call = clnt_vc_call;
761 		ops.cl_abort = clnt_vc_abort;
762 		ops.cl_geterr = clnt_vc_geterr;
763 		ops.cl_freeres = clnt_vc_freeres;
764 		ops.cl_destroy = clnt_vc_destroy;
765 		ops.cl_control = clnt_vc_control;
766 	}
767 	mutex_unlock(&ops_lock);
768 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
769 	return (&ops);
770 }
771 
772 /*
773  * Make sure that the time is not garbage.   -1 value is disallowed.
774  * Note this is different from time_not_ok in clnt_dg.c
775  */
776 static bool_t
777 time_not_ok(struct timeval *t)
778 {
779 
780 	_DIAGASSERT(t != NULL);
781 
782 	return (t->tv_sec <= -1 || t->tv_sec > 100000000 ||
783 		t->tv_usec <= -1 || t->tv_usec > 1000000);
784 }
785