xref: /netbsd-src/lib/libc/rpc/clnt_vc.c (revision da5f4674a3fc214be3572d358b66af40ab9401e7)
1 /*	$NetBSD: clnt_vc.c,v 1.9 2003/01/18 11:29:04 thorpej 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 1.9 2003/01/18 11:29:04 thorpej 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 __P((CLIENT *, rpcproc_t, xdrproc_t, caddr_t,
89     xdrproc_t, caddr_t, struct timeval));
90 static void clnt_vc_geterr __P((CLIENT *, struct rpc_err *));
91 static bool_t clnt_vc_freeres __P((CLIENT *, xdrproc_t, caddr_t));
92 static void clnt_vc_abort __P((CLIENT *));
93 static bool_t clnt_vc_control __P((CLIENT *, u_int, char *));
94 static void clnt_vc_destroy __P((CLIENT *));
95 static struct clnt_ops *clnt_vc_ops __P((void));
96 static bool_t time_not_ok __P((struct timeval *));
97 static int read_vc __P((caddr_t, caddr_t, int));
98 static int write_vc __P((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 extern int __isthreaded;
130 #define __rpc_lock_value __isthreaded;
131 extern mutex_t  clnt_fd_lock;
132 static cond_t   *vc_cv;
133 #define release_fd_lock(fd, mask) {             \
134 	mutex_lock(&clnt_fd_lock);      \
135 	vc_fd_locks[fd] = 0;            \
136 	mutex_unlock(&clnt_fd_lock);    \
137 	thr_sigsetmask(SIG_SETMASK, &(mask), (sigset_t *) NULL);        \
138 	cond_signal(&vc_cv[fd]);        \
139 }
140 #else
141 #define release_fd_lock(fd,mask)
142 #define __rpc_lock_value 0
143 #endif
144 
145 
146 /*
147  * Create a client handle for a connection.
148  * Default options are set, which the user can change using clnt_control()'s.
149  * The rpc/vc package does buffering similar to stdio, so the client
150  * must pick send and receive buffer sizes, 0 => use the default.
151  * NB: fd is copied into a private area.
152  * NB: The rpch->cl_auth is set null authentication. Caller may wish to
153  * set this something more useful.
154  *
155  * fd should be an open socket
156  */
157 CLIENT *
158 clnt_vc_create(fd, raddr, prog, vers, sendsz, recvsz)
159 	int fd;
160 	const struct netbuf *raddr;
161 	rpcprog_t prog;
162 	rpcvers_t vers;
163 	u_int sendsz;
164 	u_int recvsz;
165 {
166 	CLIENT *h;
167 	struct ct_data *ct = NULL;
168 	struct timeval now;
169 	struct rpc_msg call_msg;
170 	static u_int32_t disrupt;
171 #ifdef _REENTRANT
172 	sigset_t mask;
173 #endif
174 	sigset_t newmask;
175 	struct sockaddr_storage ss;
176 	socklen_t slen;
177 	struct __rpc_sockinfo si;
178 
179 	_DIAGASSERT(raddr != NULL);
180 
181 	if (disrupt == 0)
182 		disrupt = (u_int32_t)(long)raddr;
183 
184 	h  = mem_alloc(sizeof(*h));
185 	if (h == NULL) {
186 		warnx("clnt_vc_create: out of memory");
187 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
188 		rpc_createerr.cf_error.re_errno = errno;
189 		goto fooy;
190 	}
191 	ct = mem_alloc(sizeof(*ct));
192 	if (ct == NULL) {
193 		warnx("clnt_vc_create: out of memory");
194 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
195 		rpc_createerr.cf_error.re_errno = errno;
196 		goto fooy;
197 	}
198 
199 	sigfillset(&newmask);
200 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
201 #ifdef _REENTRANT
202 	mutex_lock(&clnt_fd_lock);
203 	if (vc_fd_locks == (int *) NULL) {
204 		size_t cv_allocsz, fd_allocsz;
205 		int dtbsize = __rpc_dtbsize();
206 
207 		fd_allocsz = dtbsize * sizeof (int);
208 		vc_fd_locks = (int *) mem_alloc(fd_allocsz);
209 		if (vc_fd_locks == (int *) NULL) {
210 			mutex_unlock(&clnt_fd_lock);
211 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
212 			goto fooy;
213 		} else
214 			memset(vc_fd_locks, '\0', fd_allocsz);
215 
216 		assert(vc_cv == (cond_t *) NULL);
217 		cv_allocsz = dtbsize * sizeof (cond_t);
218 		vc_cv = (cond_t *) mem_alloc(cv_allocsz);
219 		if (vc_cv == (cond_t *) NULL) {
220 			mem_free(vc_fd_locks, fd_allocsz);
221 			vc_fd_locks = (int *) NULL;
222 			mutex_unlock(&clnt_fd_lock);
223 			thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
224 			goto fooy;
225 		} else {
226 			int i;
227 
228 			for (i = 0; i < dtbsize; i++)
229 				cond_init(&vc_cv[i], 0, (void *) 0);
230 		}
231 	} else
232 		assert(vc_cv != (cond_t *) NULL);
233 #endif
234 
235 	/*
236 	 * XXX - fvdl connecting while holding a mutex?
237 	 */
238 	slen = sizeof ss;
239 	if (getpeername(fd, (struct sockaddr *)(void *)&ss, &slen) < 0) {
240 		if (errno != ENOTCONN) {
241 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
242 			rpc_createerr.cf_error.re_errno = errno;
243 			mutex_unlock(&clnt_fd_lock);
244 			goto fooy;
245 		}
246 		if (connect(fd, (struct sockaddr *)raddr->buf, raddr->len) < 0){
247 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
248 			rpc_createerr.cf_error.re_errno = errno;
249 			mutex_unlock(&clnt_fd_lock);
250 			goto fooy;
251 		}
252 	}
253 	mutex_unlock(&clnt_fd_lock);
254 	if (!__rpc_fd2sockinfo(fd, &si))
255 		goto fooy;
256 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
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(raddr->maxlen);
267 	if (ct->ct_addr.buf == NULL)
268 		goto fooy;
269 	memcpy(ct->ct_addr.buf, &raddr->buf, raddr->len);
270 	ct->ct_addr.len = raddr->maxlen;
271 	ct->ct_addr.maxlen = raddr->maxlen;
272 
273 	/*
274 	 * Initialize call message
275 	 */
276 	(void)gettimeofday(&now, NULL);
277 	call_msg.rm_xid = ((u_int32_t)++disrupt) ^ __RPC_GETXID(&now);
278 	call_msg.rm_direction = CALL;
279 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
280 	call_msg.rm_call.cb_prog = (u_int32_t)prog;
281 	call_msg.rm_call.cb_vers = (u_int32_t)vers;
282 
283 	/*
284 	 * pre-serialize the static part of the call msg and stash it away
285 	 */
286 	xdrmem_create(&(ct->ct_xdrs), ct->ct_u.ct_mcallc, MCALL_MSG_SIZE,
287 	    XDR_ENCODE);
288 	if (! xdr_callhdr(&(ct->ct_xdrs), &call_msg)) {
289 		if (ct->ct_closeit) {
290 			(void)close(fd);
291 		}
292 		goto fooy;
293 	}
294 	ct->ct_mpos = XDR_GETPOS(&(ct->ct_xdrs));
295 	XDR_DESTROY(&(ct->ct_xdrs));
296 
297 	/*
298 	 * Create a client handle which uses xdrrec for serialization
299 	 * and authnone for authentication.
300 	 */
301 	h->cl_ops = clnt_vc_ops();
302 	h->cl_private = ct;
303 	h->cl_auth = authnone_create();
304 	sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
305 	recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
306 	xdrrec_create(&(ct->ct_xdrs), sendsz, recvsz,
307 	    h->cl_private, read_vc, write_vc);
308 	return (h);
309 
310 fooy:
311 	/*
312 	 * Something goofed, free stuff and barf
313 	 */
314 	if (ct)
315 		mem_free(ct, sizeof(struct ct_data));
316 	if (h)
317 		mem_free(h, sizeof(CLIENT));
318 	return (NULL);
319 }
320 
321 static enum clnt_stat
322 clnt_vc_call(h, proc, xdr_args, args_ptr, xdr_results, results_ptr, timeout)
323 	CLIENT *h;
324 	rpcproc_t proc;
325 	xdrproc_t xdr_args;
326 	caddr_t args_ptr;
327 	xdrproc_t xdr_results;
328 	caddr_t results_ptr;
329 	struct timeval timeout;
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, 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(h, errp)
453 	CLIENT *h;
454 	struct rpc_err *errp;
455 {
456 	struct ct_data *ct;
457 
458 	_DIAGASSERT(h != NULL);
459 	_DIAGASSERT(errp != NULL);
460 
461 	ct = (struct ct_data *) h->cl_private;
462 	*errp = ct->ct_error;
463 }
464 
465 static bool_t
466 clnt_vc_freeres(cl, xdr_res, res_ptr)
467 	CLIENT *cl;
468 	xdrproc_t xdr_res;
469 	caddr_t res_ptr;
470 {
471 	struct ct_data *ct;
472 	XDR *xdrs;
473 	bool_t dummy;
474 #ifdef _REENTRANT
475 	sigset_t mask;
476 #endif
477 	sigset_t newmask;
478 
479 	_DIAGASSERT(cl != NULL);
480 
481 	ct = (struct ct_data *)cl->cl_private;
482 	xdrs = &(ct->ct_xdrs);
483 
484 	sigfillset(&newmask);
485 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
486 	mutex_lock(&clnt_fd_lock);
487 #ifdef _REENTRANT
488 	while (vc_fd_locks[ct->ct_fd])
489 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
490 #endif
491 
492 	xdrs->x_op = XDR_FREE;
493 	dummy = (*xdr_res)(xdrs, res_ptr);
494 	mutex_unlock(&clnt_fd_lock);
495 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
496 	cond_signal(&vc_cv[ct->ct_fd]);
497 
498 	return dummy;
499 }
500 
501 /*ARGSUSED*/
502 static void
503 clnt_vc_abort(cl)
504 	CLIENT *cl;
505 {
506 }
507 
508 static bool_t
509 clnt_vc_control(cl, request, info)
510 	CLIENT *cl;
511 	u_int request;
512 	char *info;
513 {
514 	struct ct_data *ct;
515 	void *infop = info;
516 #ifdef _REENTRANT
517 	sigset_t mask;
518 #endif
519 	sigset_t newmask;
520 
521 	_DIAGASSERT(cl != NULL);
522 
523 	ct = (struct ct_data *)cl->cl_private;
524 
525 	sigfillset(&newmask);
526 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
527 	mutex_lock(&clnt_fd_lock);
528 #ifdef _REENTRANT
529 	while (vc_fd_locks[ct->ct_fd])
530 		cond_wait(&vc_cv[ct->ct_fd], &clnt_fd_lock);
531 	vc_fd_locks[ct->ct_fd] = __rpc_lock_value;
532 #endif
533 	mutex_unlock(&clnt_fd_lock);
534 
535 	switch (request) {
536 	case CLSET_FD_CLOSE:
537 		ct->ct_closeit = TRUE;
538 		release_fd_lock(ct->ct_fd, mask);
539 		return (TRUE);
540 	case CLSET_FD_NCLOSE:
541 		ct->ct_closeit = FALSE;
542 		release_fd_lock(ct->ct_fd, mask);
543 		return (TRUE);
544 	default:
545 		break;
546 	}
547 
548 	/* for other requests which use info */
549 	if (info == NULL) {
550 		release_fd_lock(ct->ct_fd, mask);
551 		return (FALSE);
552 	}
553 	switch (request) {
554 	case CLSET_TIMEOUT:
555 		if (time_not_ok((struct timeval *)(void *)info)) {
556 			release_fd_lock(ct->ct_fd, mask);
557 			return (FALSE);
558 		}
559 		ct->ct_wait = *(struct timeval *)infop;
560 		ct->ct_waitset = TRUE;
561 		break;
562 	case CLGET_TIMEOUT:
563 		*(struct timeval *)infop = ct->ct_wait;
564 		break;
565 	case CLGET_SERVER_ADDR:
566 		(void) memcpy(info, ct->ct_addr.buf, (size_t)ct->ct_addr.len);
567 		break;
568 	case CLGET_FD:
569 		*(int *)(void *)info = ct->ct_fd;
570 		break;
571 	case CLGET_SVC_ADDR:
572 		/* The caller should not free this memory area */
573 		*(struct netbuf *)(void *)info = ct->ct_addr;
574 		break;
575 	case CLSET_SVC_ADDR:		/* set to new address */
576 		release_fd_lock(ct->ct_fd, mask);
577 		return (FALSE);
578 	case CLGET_XID:
579 		/*
580 		 * use the knowledge that xid is the
581 		 * first element in the call structure
582 		 * This will get the xid of the PREVIOUS call
583 		 */
584 		*(u_int32_t *)(void *)info =
585 		    ntohl(*(u_int32_t *)(void *)&ct->ct_u.ct_mcalli);
586 		break;
587 	case CLSET_XID:
588 		/* This will set the xid of the NEXT call */
589 		*(u_int32_t *)(void *)&ct->ct_u.ct_mcalli =
590 		    htonl(*((u_int32_t *)(void *)info) + 1);
591 		/* increment by 1 as clnt_vc_call() decrements once */
592 		break;
593 	case CLGET_VERS:
594 		/*
595 		 * This RELIES on the information that, in the call body,
596 		 * the version number field is the fifth field from the
597 		 * begining of the RPC header. MUST be changed if the
598 		 * call_struct is changed
599 		 */
600 		*(u_int32_t *)(void *)info =
601 		    ntohl(*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
602 		    4 * BYTES_PER_XDR_UNIT));
603 		break;
604 
605 	case CLSET_VERS:
606 		*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
607 		    4 * BYTES_PER_XDR_UNIT) =
608 		    htonl(*(u_int32_t *)(void *)info);
609 		break;
610 
611 	case CLGET_PROG:
612 		/*
613 		 * This RELIES on the information that, in the call body,
614 		 * the program number field is the fourth field from the
615 		 * begining of the RPC header. MUST be changed if the
616 		 * call_struct is changed
617 		 */
618 		*(u_int32_t *)(void *)info =
619 		    ntohl(*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
620 		    3 * BYTES_PER_XDR_UNIT));
621 		break;
622 
623 	case CLSET_PROG:
624 		*(u_int32_t *)(void *)(ct->ct_u.ct_mcallc +
625 		    3 * BYTES_PER_XDR_UNIT) =
626 		    htonl(*(u_int32_t *)(void *)info);
627 		break;
628 
629 	default:
630 		release_fd_lock(ct->ct_fd, mask);
631 		return (FALSE);
632 	}
633 	release_fd_lock(ct->ct_fd, mask);
634 	return (TRUE);
635 }
636 
637 
638 static void
639 clnt_vc_destroy(cl)
640 	CLIENT *cl;
641 {
642 	struct ct_data *ct;
643 #ifdef _REENTRANT
644 	int ct_fd;
645 	sigset_t mask;
646 #endif
647 	sigset_t newmask;
648 
649 	_DIAGASSERT(cl != NULL);
650 
651 	ct = (struct ct_data *) cl->cl_private;
652 	ct_fd = ct->ct_fd;
653 
654 	sigfillset(&newmask);
655 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
656 	mutex_lock(&clnt_fd_lock);
657 #ifdef _REENTRANT
658 	while (vc_fd_locks[ct_fd])
659 		cond_wait(&vc_cv[ct_fd], &clnt_fd_lock);
660 #endif
661 	if (ct->ct_closeit && ct->ct_fd != -1) {
662 		(void)close(ct->ct_fd);
663 	}
664 	XDR_DESTROY(&(ct->ct_xdrs));
665 	if (ct->ct_addr.buf)
666 		free(ct->ct_addr.buf);
667 	mem_free(ct, sizeof(struct ct_data));
668 	mem_free(cl, sizeof(CLIENT));
669 	mutex_unlock(&clnt_fd_lock);
670 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
671 
672 	cond_signal(&vc_cv[ct_fd]);
673 }
674 
675 /*
676  * Interface between xdr serializer and tcp connection.
677  * Behaves like the system calls, read & write, but keeps some error state
678  * around for the rpc level.
679  */
680 static int
681 read_vc(ctp, buf, len)
682 	caddr_t ctp;
683 	caddr_t buf;
684 	int len;
685 {
686 	struct ct_data *ct = (struct ct_data *)(void *)ctp;
687 	struct pollfd fd;
688 	int milliseconds = (int)((ct->ct_wait.tv_sec * 1000) +
689 	    (ct->ct_wait.tv_usec / 1000));
690 
691 	if (len == 0)
692 		return (0);
693 	fd.fd = ct->ct_fd;
694 	fd.events = POLLIN;
695 	for (;;) {
696 		switch (poll(&fd, 1, milliseconds)) {
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 (len = 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 (len);
725 }
726 
727 static int
728 write_vc(ctp, buf, len)
729 	caddr_t ctp;
730 	caddr_t buf;
731 	int len;
732 {
733 	struct ct_data *ct = (struct ct_data *)(void *)ctp;
734 	int i, cnt;
735 
736 	for (cnt = len; cnt > 0; cnt -= i, buf += i) {
737 		if ((i = write(ct->ct_fd, buf, (size_t)cnt)) == -1) {
738 			ct->ct_error.re_errno = errno;
739 			ct->ct_error.re_status = RPC_CANTSEND;
740 			return (-1);
741 		}
742 	}
743 	return (len);
744 }
745 
746 static struct clnt_ops *
747 clnt_vc_ops()
748 {
749 	static struct clnt_ops ops;
750 #ifdef _REENTRANT
751 	extern mutex_t  ops_lock;
752 	sigset_t mask;
753 #endif
754 	sigset_t newmask;
755 
756 	/* VARIABLES PROTECTED BY ops_lock: ops */
757 
758 	sigfillset(&newmask);
759 	thr_sigsetmask(SIG_SETMASK, &newmask, &mask);
760 	mutex_lock(&ops_lock);
761 	if (ops.cl_call == NULL) {
762 		ops.cl_call = clnt_vc_call;
763 		ops.cl_abort = clnt_vc_abort;
764 		ops.cl_geterr = clnt_vc_geterr;
765 		ops.cl_freeres = clnt_vc_freeres;
766 		ops.cl_destroy = clnt_vc_destroy;
767 		ops.cl_control = clnt_vc_control;
768 	}
769 	mutex_unlock(&ops_lock);
770 	thr_sigsetmask(SIG_SETMASK, &(mask), NULL);
771 	return (&ops);
772 }
773 
774 /*
775  * Make sure that the time is not garbage.   -1 value is disallowed.
776  * Note this is different from time_not_ok in clnt_dg.c
777  */
778 static bool_t
779 time_not_ok(t)
780 	struct timeval *t;
781 {
782 
783 	_DIAGASSERT(t != NULL);
784 
785 	return (t->tv_sec <= -1 || t->tv_sec > 100000000 ||
786 		t->tv_usec <= -1 || t->tv_usec > 1000000);
787 }
788