xref: /minix3/lib/libc/rpc/clnt_vc.c (revision f14fb602092e015ff630df58e17c2a9cd57d29b3)
1 /*	$NetBSD: clnt_vc.c,v 1.18 2012/03/13 21:13:44 christos Exp $	*/
2 
3 /*
4  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5  * unrestricted use provided that this legend is included on all tape
6  * media and as a part of the software program in whole or part.  Users
7  * may copy or modify Sun RPC without charge, but are not authorized
8  * to license or distribute it to anyone else except as part of a product or
9  * program developed by the user.
10  *
11  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14  *
15  * Sun RPC is provided with no support and without any obligation on the
16  * part of Sun Microsystems, Inc. to assist in its use, correction,
17  * modification or enhancement.
18  *
19  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21  * OR ANY PART THEREOF.
22  *
23  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24  * or profits or other special, indirect and consequential damages, even if
25  * Sun has been advised of the possibility of such damages.
26  *
27  * Sun Microsystems, Inc.
28  * 2550 Garcia Avenue
29  * Mountain View, California  94043
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char *sccsid = "@(#)clnt_tcp.c 1.37 87/10/05 Copyr 1984 Sun Micro";
36 static char *sccsid = "@(#)clnt_tcp.c	2.2 88/08/01 4.0 RPCSRC";
37 static char sccsid[] = "@(#)clnt_vc.c 1.19 89/03/16 Copyr 1988 Sun Micro";
38 #else
39 __RCSID("$NetBSD: clnt_vc.c,v 1.18 2012/03/13 21:13:44 christos Exp $");
40 #endif
41 #endif
42 
43 /*
44  * clnt_tcp.c, Implements a TCP/IP based, client side RPC.
45  *
46  * Copyright (C) 1984, Sun Microsystems, Inc.
47  *
48  * TCP based RPC supports 'batched calls'.
49  * A sequence of calls may be batched-up in a send buffer.  The rpc call
50  * return immediately to the client even though the call was not necessarily
51  * sent.  The batching occurs if the results' xdr routine is NULL (0) AND
52  * the rpc timeout value is zero (see clnt.h, rpc).
53  *
54  * Clients should NOT casually batch calls that in fact return results; that is,
55  * the server side should be aware that a call is batched and not produce any
56  * return message.  Batched calls that produce many result messages can
57  * deadlock (netlock) the client and the server....
58  *
59  * Now go hang yourself.
60  */
61 
62 #include "namespace.h"
63 #include "reentrant.h"
64 #include <sys/types.h>
65 #include <sys/poll.h>
66 #include <sys/socket.h>
67 
68 #include <assert.h>
69 #include <err.h>
70 #include <errno.h>
71 #include <netdb.h>
72 #include <stdio.h>
73 #include <stdlib.h>
74 #include <string.h>
75 #include <unistd.h>
76 #include <signal.h>
77 
78 #include <rpc/rpc.h>
79 
80 #include "rpc_internal.h"
81 
82 #ifdef __weak_alias
83 __weak_alias(clnt_vc_create,_clnt_vc_create)
84 #endif
85 
86 #define MCALL_MSG_SIZE 24
87 
88 static enum clnt_stat clnt_vc_call(CLIENT *, rpcproc_t, xdrproc_t,
89     const char *, xdrproc_t, caddr_t, struct timeval);
90 static void clnt_vc_geterr(CLIENT *, struct rpc_err *);
91 static bool_t clnt_vc_freeres(CLIENT *, xdrproc_t, caddr_t);
92 static void clnt_vc_abort(CLIENT *);
93 static bool_t clnt_vc_control(CLIENT *, u_int, char *);
94 static void clnt_vc_destroy(CLIENT *);
95 static struct clnt_ops *clnt_vc_ops(void);
96 static bool_t time_not_ok(struct timeval *);
97 static int read_vc(caddr_t, caddr_t, int);
98 static int write_vc(caddr_t, caddr_t, int);
99 
100 struct ct_data {
101 	int		ct_fd;
102 	bool_t		ct_closeit;
103 	struct timeval	ct_wait;
104 	bool_t          ct_waitset;       /* wait set by clnt_control? */
105 	struct netbuf	ct_addr;
106 	struct rpc_err	ct_error;
107 	union {
108 		char	ct_mcallc[MCALL_MSG_SIZE];	/* marshalled callmsg */
109 		u_int32_t ct_mcalli;
110 	} ct_u;
111 	u_int		ct_mpos;			/* pos after marshal */
112 	XDR		ct_xdrs;
113 };
114 
115 /*
116  *      This machinery implements per-fd locks for MT-safety.  It is not
117  *      sufficient to do per-CLIENT handle locks for MT-safety because a
118  *      user may create more than one CLIENT handle with the same fd behind
119  *      it.  Therfore, we allocate an array of flags (vc_fd_locks), protected
120  *      by the clnt_fd_lock mutex, and an array (vc_cv) of condition variables
121  *      similarly protected.  Vc_fd_lock[fd] == 1 => a call is activte on some
122  *      CLIENT handle created for that fd.
123  *      The current implementation holds locks across the entire RPC and reply.
124  *      Yes, this is silly, and as soon as this code is proven to work, this
125  *      should be the first thing fixed.  One step at a time.
126  */
127 #ifdef _REENTRANT
128 static int      *vc_fd_locks;
129 #define __rpc_lock_value __isthreaded;
130 extern mutex_t  clnt_fd_lock;
131 static cond_t   *vc_cv;
132 #define release_fd_lock(fd, mask) {             \
133 	mutex_lock(&clnt_fd_lock);      \
134 	vc_fd_locks[fd] = 0;            \
135 	mutex_unlock(&clnt_fd_lock);    \
136 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);        \
137 	cond_signal(&vc_cv[fd]);        \
138 }
139 #else
140 #define release_fd_lock(fd,mask)
141 #define __rpc_lock_value 0
142 #endif
143 
144 
145 /*
146  * Create a client handle for a connection.
147  * Default options are set, which the user can change using clnt_control()'s.
148  * The rpc/vc package does buffering similar to stdio, so the client
149  * must pick send and receive buffer sizes, 0 => use the default.
150  * NB: fd is copied into a private area.
151  * NB: The rpch->cl_auth is set null authentication. Caller may wish to
152  * set this something more useful.
153  *
154  * fd should be an open socket
155  */
156 CLIENT *
157 clnt_vc_create(
158 	int fd,
159 	const struct netbuf *raddr,
160 	rpcprog_t prog,
161 	rpcvers_t vers,
162 	u_int sendsz,
163 	u_int recvsz
164 )
165 {
166 	CLIENT *h;
167 	struct ct_data *ct = NULL;
168 	struct rpc_msg call_msg;
169 #ifdef _REENTRANT
170 	sigset_t mask;
171 #endif
172 	sigset_t newmask;
173 	struct sockaddr_storage ss;
174 	socklen_t slen;
175 	struct __rpc_sockinfo si;
176 
177 	_DIAGASSERT(raddr != NULL);
178 
179 	h  = mem_alloc(sizeof(*h));
180 	if (h == NULL) {
181 		warnx("clnt_vc_create: out of memory");
182 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
183 		rpc_createerr.cf_error.re_errno = errno;
184 		goto fooy;
185 	}
186 	ct = mem_alloc(sizeof(*ct));
187 	if (ct == NULL) {
188 		warnx("clnt_vc_create: out of memory");
189 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
190 		rpc_createerr.cf_error.re_errno = errno;
191 		goto fooy;
192 	}
193 
194 	sigfillset(&newmask);
195 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
196 #ifdef _REENTRANT
197 	mutex_lock(&clnt_fd_lock);
198 	if (vc_fd_locks == NULL) {
199 		size_t cv_allocsz, fd_allocsz;
200 		int dtbsize = __rpc_dtbsize();
201 
202 		fd_allocsz = dtbsize * sizeof (int);
203 		vc_fd_locks = mem_alloc(fd_allocsz);
204 		if (vc_fd_locks == NULL) {
205 			mutex_unlock(&clnt_fd_lock);
206 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
207 			goto fooy;
208 		} else
209 			memset(vc_fd_locks, '\0', fd_allocsz);
210 
211 		_DIAGASSERT(vc_cv == NULL);
212 		cv_allocsz = dtbsize * sizeof (cond_t);
213 		vc_cv = mem_alloc(cv_allocsz);
214 		if (vc_cv == NULL) {
215 			mem_free(vc_fd_locks, fd_allocsz);
216 			vc_fd_locks = NULL;
217 			mutex_unlock(&clnt_fd_lock);
218 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
219 			goto fooy;
220 		} else {
221 			int i;
222 
223 			for (i = 0; i < dtbsize; i++)
224 				cond_init(&vc_cv[i], 0, (void *) 0);
225 		}
226 	} else
227 		_DIAGASSERT(vc_cv != NULL);
228 #endif
229 
230 	/*
231 	 * XXX - fvdl connecting while holding a mutex?
232 	 */
233 	slen = sizeof ss;
234 	if (getpeername(fd, (struct sockaddr *)(void *)&ss, &slen) < 0) {
235 		if (errno != ENOTCONN) {
236 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
237 			rpc_createerr.cf_error.re_errno = errno;
238 			mutex_unlock(&clnt_fd_lock);
239 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
240 			goto fooy;
241 		}
242 		if (connect(fd, (struct sockaddr *)raddr->buf, raddr->len) < 0){
243 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
244 			rpc_createerr.cf_error.re_errno = errno;
245 			mutex_unlock(&clnt_fd_lock);
246 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
247 			goto fooy;
248 		}
249 	}
250 	mutex_unlock(&clnt_fd_lock);
251 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
252 	if (!__rpc_fd2sockinfo(fd, &si))
253 		goto fooy;
254 
255 	ct->ct_closeit = FALSE;
256 
257 	/*
258 	 * Set up private data struct
259 	 */
260 	ct->ct_fd = fd;
261 	ct->ct_wait.tv_usec = 0;
262 	ct->ct_waitset = FALSE;
263 	ct->ct_addr.buf = malloc((size_t)raddr->maxlen);
264 	if (ct->ct_addr.buf == NULL)
265 		goto fooy;
266 	memcpy(ct->ct_addr.buf, &raddr->buf, (size_t)raddr->len);
267 	ct->ct_addr.len = raddr->maxlen;
268 	ct->ct_addr.maxlen = raddr->maxlen;
269 
270 	/*
271 	 * Initialize call message
272 	 */
273 	call_msg.rm_xid = __RPC_GETXID();
274 	call_msg.rm_direction = CALL;
275 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
276 	call_msg.rm_call.cb_prog = (u_int32_t)prog;
277 	call_msg.rm_call.cb_vers = (u_int32_t)vers;
278 
279 	/*
280 	 * pre-serialize the static part of the call msg and stash it away
281 	 */
282 	xdrmem_create(&(ct->ct_xdrs), ct->ct_u.ct_mcallc, MCALL_MSG_SIZE,
283 	    XDR_ENCODE);
284 	if (! xdr_callhdr(&(ct->ct_xdrs), &call_msg)) {
285 		if (ct->ct_closeit) {
286 			(void)close(fd);
287 		}
288 		goto fooy;
289 	}
290 	ct->ct_mpos = XDR_GETPOS(&(ct->ct_xdrs));
291 	XDR_DESTROY(&(ct->ct_xdrs));
292 
293 	/*
294 	 * Create a client handle which uses xdrrec for serialization
295 	 * and authnone for authentication.
296 	 */
297 	h->cl_ops = clnt_vc_ops();
298 	h->cl_private = ct;
299 	h->cl_auth = authnone_create();
300 	sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
301 	recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
302 	xdrrec_create(&(ct->ct_xdrs), sendsz, recvsz,
303 	    h->cl_private, read_vc, write_vc);
304 	return (h);
305 
306 fooy:
307 	/*
308 	 * Something goofed, free stuff and barf
309 	 */
310 	if (ct)
311 		mem_free(ct, sizeof(struct ct_data));
312 	if (h)
313 		mem_free(h, sizeof(CLIENT));
314 	return (NULL);
315 }
316 
317 static enum clnt_stat
318 clnt_vc_call(
319 	CLIENT *h,
320 	rpcproc_t proc,
321 	xdrproc_t xdr_args,
322 	const char *args_ptr,
323 	xdrproc_t xdr_results,
324 	caddr_t results_ptr,
325 	struct timeval timeout
326 )
327 {
328 	struct ct_data *ct;
329 	XDR *xdrs;
330 	struct rpc_msg reply_msg;
331 	u_int32_t x_id;
332 	u_int32_t *msg_x_id;
333 	bool_t shipnow;
334 	int refreshes = 2;
335 #ifdef _REENTRANT
336 	sigset_t mask, newmask;
337 #endif
338 
339 	_DIAGASSERT(h != NULL);
340 
341 	ct = (struct ct_data *) h->cl_private;
342 
343 #ifdef _REENTRANT
344 	sigfillset(&newmask);
345 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
346 	mutex_lock(&clnt_fd_lock);
347 	while (vc_fd_locks[ct->ct_fd])
348 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
349 	vc_fd_locks[ct->ct_fd] = __rpc_lock_value;
350 	mutex_unlock(&clnt_fd_lock);
351 #endif
352 
353 	xdrs = &(ct->ct_xdrs);
354 	msg_x_id = &ct->ct_u.ct_mcalli;
355 
356 	if (!ct->ct_waitset) {
357 		if (time_not_ok(&timeout) == FALSE)
358 		ct->ct_wait = timeout;
359 	}
360 
361 	shipnow =
362 	    (xdr_results == NULL && timeout.tv_sec == 0
363 	    && timeout.tv_usec == 0) ? FALSE : TRUE;
364 
365 call_again:
366 	xdrs->x_op = XDR_ENCODE;
367 	ct->ct_error.re_status = RPC_SUCCESS;
368 	x_id = ntohl(--(*msg_x_id));
369 	if ((! XDR_PUTBYTES(xdrs, ct->ct_u.ct_mcallc, ct->ct_mpos)) ||
370 	    (! XDR_PUTINT32(xdrs, (int32_t *)&proc)) ||
371 	    (! AUTH_MARSHALL(h->cl_auth, xdrs)) ||
372 	    (! (*xdr_args)(xdrs, __UNCONST(args_ptr)))) {
373 		if (ct->ct_error.re_status == RPC_SUCCESS)
374 			ct->ct_error.re_status = RPC_CANTENCODEARGS;
375 		(void)xdrrec_endofrecord(xdrs, TRUE);
376 		release_fd_lock(ct->ct_fd, mask);
377 		return (ct->ct_error.re_status);
378 	}
379 	if (! xdrrec_endofrecord(xdrs, shipnow)) {
380 		release_fd_lock(ct->ct_fd, mask);
381 		return (ct->ct_error.re_status = RPC_CANTSEND);
382 	}
383 	if (! shipnow) {
384 		release_fd_lock(ct->ct_fd, mask);
385 		return (RPC_SUCCESS);
386 	}
387 	/*
388 	 * Hack to provide rpc-based message passing
389 	 */
390 	if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
391 		release_fd_lock(ct->ct_fd, mask);
392 		return(ct->ct_error.re_status = RPC_TIMEDOUT);
393 	}
394 
395 
396 	/*
397 	 * Keep receiving until we get a valid transaction id
398 	 */
399 	xdrs->x_op = XDR_DECODE;
400 	for (;;) {
401 		reply_msg.acpted_rply.ar_verf = _null_auth;
402 		reply_msg.acpted_rply.ar_results.where = NULL;
403 		reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
404 		if (! xdrrec_skiprecord(xdrs)) {
405 			release_fd_lock(ct->ct_fd, mask);
406 			return (ct->ct_error.re_status);
407 		}
408 		/* now decode and validate the response header */
409 		if (! xdr_replymsg(xdrs, &reply_msg)) {
410 			if (ct->ct_error.re_status == RPC_SUCCESS)
411 				continue;
412 			release_fd_lock(ct->ct_fd, mask);
413 			return (ct->ct_error.re_status);
414 		}
415 		if (reply_msg.rm_xid == x_id)
416 			break;
417 	}
418 
419 	/*
420 	 * process header
421 	 */
422 	_seterr_reply(&reply_msg, &(ct->ct_error));
423 	if (ct->ct_error.re_status == RPC_SUCCESS) {
424 		if (! AUTH_VALIDATE(h->cl_auth,
425 		    &reply_msg.acpted_rply.ar_verf)) {
426 			ct->ct_error.re_status = RPC_AUTHERROR;
427 			ct->ct_error.re_why = AUTH_INVALIDRESP;
428 		} else if (! (*xdr_results)(xdrs, results_ptr)) {
429 			if (ct->ct_error.re_status == RPC_SUCCESS)
430 				ct->ct_error.re_status = RPC_CANTDECODERES;
431 		}
432 		/* free verifier ... */
433 		if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
434 			xdrs->x_op = XDR_FREE;
435 			(void)xdr_opaque_auth(xdrs,
436 			    &(reply_msg.acpted_rply.ar_verf));
437 		}
438 	}  /* end successful completion */
439 	else {
440 		/* maybe our credentials need to be refreshed ... */
441 		if (refreshes-- && AUTH_REFRESH(h->cl_auth))
442 			goto call_again;
443 	}  /* end of unsuccessful completion */
444 	release_fd_lock(ct->ct_fd, mask);
445 	return (ct->ct_error.re_status);
446 }
447 
448 static void
449 clnt_vc_geterr(
450 	CLIENT *h,
451 	struct rpc_err *errp
452 )
453 {
454 	struct ct_data *ct;
455 
456 	_DIAGASSERT(h != NULL);
457 	_DIAGASSERT(errp != NULL);
458 
459 	ct = (struct ct_data *) h->cl_private;
460 	*errp = ct->ct_error;
461 }
462 
463 static bool_t
464 clnt_vc_freeres(
465 	CLIENT *cl,
466 	xdrproc_t xdr_res,
467 	caddr_t res_ptr
468 )
469 {
470 	struct ct_data *ct;
471 	XDR *xdrs;
472 	bool_t dummy;
473 #ifdef _REENTRANT
474 	sigset_t mask;
475 #endif
476 	sigset_t newmask;
477 
478 	_DIAGASSERT(cl != NULL);
479 
480 	ct = (struct ct_data *)cl->cl_private;
481 	xdrs = &(ct->ct_xdrs);
482 
483 	sigfillset(&newmask);
484 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
485 	mutex_lock(&clnt_fd_lock);
486 #ifdef _REENTRANT
487 	while (vc_fd_locks[ct->ct_fd])
488 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
489 #endif
490 
491 	xdrs->x_op = XDR_FREE;
492 	dummy = (*xdr_res)(xdrs, res_ptr);
493 	mutex_unlock(&clnt_fd_lock);
494 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
495 	cond_signal(&vc_cv[ct->ct_fd]);
496 
497 	return dummy;
498 }
499 
500 /*ARGSUSED*/
501 static void
502 clnt_vc_abort(CLIENT *cl)
503 {
504 }
505 
506 static bool_t
507 clnt_vc_control(
508 	CLIENT *cl,
509 	u_int request,
510 	char *info
511 )
512 {
513 	struct ct_data *ct;
514 	void *infop = info;
515 #ifdef _REENTRANT
516 	sigset_t mask;
517 #endif
518 	sigset_t newmask;
519 
520 	_DIAGASSERT(cl != NULL);
521 
522 	ct = (struct ct_data *)cl->cl_private;
523 
524 	sigfillset(&newmask);
525 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
526 	mutex_lock(&clnt_fd_lock);
527 #ifdef _REENTRANT
528 	while (vc_fd_locks[ct->ct_fd])
529 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
530 	vc_fd_locks[ct->ct_fd] = __rpc_lock_value;
531 #endif
532 	mutex_unlock(&clnt_fd_lock);
533 
534 	switch (request) {
535 	case CLSET_FD_CLOSE:
536 		ct->ct_closeit = TRUE;
537 		release_fd_lock(ct->ct_fd, mask);
538 		return (TRUE);
539 	case CLSET_FD_NCLOSE:
540 		ct->ct_closeit = FALSE;
541 		release_fd_lock(ct->ct_fd, mask);
542 		return (TRUE);
543 	default:
544 		break;
545 	}
546 
547 	/* for other requests which use info */
548 	if (info == NULL) {
549 		release_fd_lock(ct->ct_fd, mask);
550 		return (FALSE);
551 	}
552 	switch (request) {
553 	case CLSET_TIMEOUT:
554 		if (time_not_ok((struct timeval *)(void *)info)) {
555 			release_fd_lock(ct->ct_fd, mask);
556 			return (FALSE);
557 		}
558 		ct->ct_wait = *(struct timeval *)infop;
559 		ct->ct_waitset = TRUE;
560 		break;
561 	case CLGET_TIMEOUT:
562 		*(struct timeval *)infop = ct->ct_wait;
563 		break;
564 	case CLGET_SERVER_ADDR:
565 		(void) memcpy(info, ct->ct_addr.buf, (size_t)ct->ct_addr.len);
566 		break;
567 	case CLGET_FD:
568 		*(int *)(void *)info = ct->ct_fd;
569 		break;
570 	case CLGET_SVC_ADDR:
571 		/* The caller should not free this memory area */
572 		*(struct netbuf *)(void *)info = ct->ct_addr;
573 		break;
574 	case CLSET_SVC_ADDR:		/* set to new address */
575 		release_fd_lock(ct->ct_fd, mask);
576 		return (FALSE);
577 	case CLGET_XID:
578 		/*
579 		 * use the knowledge that xid is the
580 		 * first element in the call structure
581 		 * This will get the xid of the PREVIOUS call
582 		 */
583 		*(u_int32_t *)(void *)info =
584 		    ntohl(*(u_int32_t *)(void *)&ct->ct_u.ct_mcalli);
585 		break;
586 	case CLSET_XID:
587 		/* This will set the xid of the NEXT call */
588 		*(u_int32_t *)(void *)&ct->ct_u.ct_mcalli =
589 		    htonl(*((u_int32_t *)(void *)info) + 1);
590 		/* increment by 1 as clnt_vc_call() decrements once */
591 		break;
592 	case CLGET_VERS:
593 		/*
594 		 * This RELIES on the information that, in the call body,
595 		 * the version number field is the fifth field from the
596 		 * begining of the RPC header. MUST be changed if the
597 		 * call_struct is changed
598 		 */
599 		*(u_int32_t *)(void *)info =
600 		    ntohl(*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
601 		    4 * BYTES_PER_XDR_UNIT));
602 		break;
603 
604 	case CLSET_VERS:
605 		*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
606 		    4 * BYTES_PER_XDR_UNIT) =
607 		    htonl(*(u_int32_t *)(void *)info);
608 		break;
609 
610 	case CLGET_PROG:
611 		/*
612 		 * This RELIES on the information that, in the call body,
613 		 * the program number field is the fourth field from the
614 		 * begining of the RPC header. MUST be changed if the
615 		 * call_struct is changed
616 		 */
617 		*(u_int32_t *)(void *)info =
618 		    ntohl(*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
619 		    3 * BYTES_PER_XDR_UNIT));
620 		break;
621 
622 	case CLSET_PROG:
623 		*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
624 		    3 * BYTES_PER_XDR_UNIT) =
625 		    htonl(*(u_int32_t *)(void *)info);
626 		break;
627 
628 	default:
629 		release_fd_lock(ct->ct_fd, mask);
630 		return (FALSE);
631 	}
632 	release_fd_lock(ct->ct_fd, mask);
633 	return (TRUE);
634 }
635 
636 
637 static void
638 clnt_vc_destroy(CLIENT *cl)
639 {
640 	struct ct_data *ct;
641 #ifdef _REENTRANT
642 	int ct_fd;
643 	sigset_t mask;
644 #endif
645 	sigset_t newmask;
646 
647 	_DIAGASSERT(cl != NULL);
648 
649 	ct = (struct ct_data *) cl->cl_private;
650 	ct_fd = ct->ct_fd;
651 
652 	sigfillset(&newmask);
653 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
654 	mutex_lock(&clnt_fd_lock);
655 #ifdef _REENTRANT
656 	while (vc_fd_locks[ct_fd])
657 		cond_wait(&vc_cv[ct_fd], &clnt_fd_lock);
658 #endif
659 	if (ct->ct_closeit && ct->ct_fd != -1) {
660 		(void)close(ct->ct_fd);
661 	}
662 	XDR_DESTROY(&(ct->ct_xdrs));
663 	if (ct->ct_addr.buf)
664 		free(ct->ct_addr.buf);
665 	mem_free(ct, sizeof(struct ct_data));
666 	mem_free(cl, sizeof(CLIENT));
667 	mutex_unlock(&clnt_fd_lock);
668 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
669 
670 	cond_signal(&vc_cv[ct_fd]);
671 }
672 
673 /*
674  * Interface between xdr serializer and tcp connection.
675  * Behaves like the system calls, read & write, but keeps some error state
676  * around for the rpc level.
677  */
678 static int
679 read_vc(char *ctp, char *buf, int len)
680 {
681 	struct ct_data *ct = (struct ct_data *)(void *)ctp;
682 	struct pollfd fd;
683 	struct timespec ts;
684 	ssize_t nread;
685 
686 	if (len == 0)
687 		return (0);
688 
689 	TIMEVAL_TO_TIMESPEC(&ct->ct_wait, &ts);
690 	fd.fd = ct->ct_fd;
691 	fd.events = POLLIN;
692 	for (;;) {
693 		switch (pollts(&fd, 1, &ts, NULL)) {
694 		case 0:
695 			ct->ct_error.re_status = RPC_TIMEDOUT;
696 			return (-1);
697 
698 		case -1:
699 			if (errno == EINTR)
700 				continue;
701 			ct->ct_error.re_status = RPC_CANTRECV;
702 			ct->ct_error.re_errno = errno;
703 			return (-1);
704 		}
705 		break;
706 	}
707 	switch (nread = read(ct->ct_fd, buf, (size_t)len)) {
708 
709 	case 0:
710 		/* premature eof */
711 		ct->ct_error.re_errno = ECONNRESET;
712 		ct->ct_error.re_status = RPC_CANTRECV;
713 		len = -1;  /* it's really an error */
714 		break;
715 
716 	case -1:
717 		ct->ct_error.re_errno = errno;
718 		ct->ct_error.re_status = RPC_CANTRECV;
719 		break;
720 	}
721 	return (int)nread;
722 }
723 
724 static int
725 write_vc(char *ctp, char *buf, int len)
726 {
727 	struct ct_data *ct = (struct ct_data *)(void *)ctp;
728 	ssize_t i;
729 	size_t cnt;
730 
731 	for (cnt = len; cnt > 0; cnt -= i, buf += i) {
732 		if ((i = write(ct->ct_fd, buf, cnt)) == -1) {
733 			ct->ct_error.re_errno = errno;
734 			ct->ct_error.re_status = RPC_CANTSEND;
735 			return (-1);
736 		}
737 	}
738 	return len;
739 }
740 
741 static struct clnt_ops *
742 clnt_vc_ops(void)
743 {
744 	static struct clnt_ops ops;
745 #ifdef _REENTRANT
746 	extern mutex_t  ops_lock;
747 	sigset_t mask;
748 #endif
749 	sigset_t newmask;
750 
751 	/* VARIABLES PROTECTED BY ops_lock: ops */
752 
753 	sigfillset(&newmask);
754 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
755 	mutex_lock(&ops_lock);
756 	if (ops.cl_call == NULL) {
757 		ops.cl_call = clnt_vc_call;
758 		ops.cl_abort = clnt_vc_abort;
759 		ops.cl_geterr = clnt_vc_geterr;
760 		ops.cl_freeres = clnt_vc_freeres;
761 		ops.cl_destroy = clnt_vc_destroy;
762 		ops.cl_control = clnt_vc_control;
763 	}
764 	mutex_unlock(&ops_lock);
765 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
766 	return (&ops);
767 }
768 
769 /*
770  * Make sure that the time is not garbage.   -1 value is disallowed.
771  * Note this is different from time_not_ok in clnt_dg.c
772  */
773 static bool_t
774 time_not_ok(struct timeval *t)
775 {
776 
777 	_DIAGASSERT(t != NULL);
778 
779 	return (t->tv_sec <= -1 || t->tv_sec > 100000000 ||
780 		t->tv_usec <= -1 || t->tv_usec > 1000000);
781 }
782