about summary refs log tree commit diff
path: root/sunrpc/clnt_udp.c
blob: 6ce16eb2988c64b5178d0ce6a1cc28271774e023 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
/*
 * clnt_udp.c, Implements a UDP/IP based, client side RPC.
 *
 * Copyright (c) 2010, Oracle America, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials
 *       provided with the distribution.
 *     * Neither the name of the "Oracle America, Inc." nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <unistd.h>
#include <libintl.h>
#include <rpc/rpc.h>
#include <rpc/xdr.h>
#include <rpc/clnt.h>
#include <sys/poll.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netdb.h>
#include <errno.h>
#include <stdint.h>
#include <rpc/pmap_clnt.h>
#include <net/if.h>
#include <ifaddrs.h>
#include <wchar.h>
#include <fcntl.h>

#ifdef IP_RECVERR
#include <errqueue.h>
#include <sys/uio.h>
#endif

#include <kernel-features.h>
#include <inet/net-internal.h>

extern u_long _create_xid (void);

/*
 * UDP bases client side rpc operations
 */
static enum clnt_stat clntudp_call (CLIENT *, u_long, xdrproc_t, caddr_t,
				    xdrproc_t, caddr_t, struct timeval);
static void clntudp_abort (void);
static void clntudp_geterr (CLIENT *, struct rpc_err *);
static bool_t clntudp_freeres (CLIENT *, xdrproc_t, caddr_t);
static bool_t clntudp_control (CLIENT *, int, char *);
static void clntudp_destroy (CLIENT *);

static const struct clnt_ops udp_ops =
{
  clntudp_call,
  clntudp_abort,
  clntudp_geterr,
  clntudp_freeres,
  clntudp_destroy,
  clntudp_control
};

/*
 * Private data kept per client handle.  This private struct is
 * unfortunately part of the ABI; ypbind contains a copy of it and
 * accesses it through CLIENT::cl_private field.
 */
struct cu_data
  {
    int cu_sock;
    bool_t cu_closeit;
    struct sockaddr_in cu_raddr;
    int cu_rlen;
    struct timeval cu_wait;
    struct timeval cu_total;
    struct rpc_err cu_error;
    XDR cu_outxdrs;
    u_int cu_xdrpos;
    u_int cu_sendsz;
    char *cu_outbuf;
    u_int cu_recvsz;
    char cu_inbuf[1];
  };

/*
 * Create a UDP based client handle.
 * If *sockp<0, *sockp is set to a newly created UPD socket.
 * If raddr->sin_port is 0 a binder on the remote machine
 * is consulted for the correct port number.
 * NB: It is the clients responsibility to close *sockp.
 * NB: The rpch->cl_auth is initialized to null authentication.
 *     Caller may wish to set this something more useful.
 *
 * wait is the amount of time used between retransmitting a call if
 * no response has been heard; retransmission occurs until the actual
 * rpc call times out.
 *
 * sendsz and recvsz are the maximum allowable packet sizes that can be
 * sent and received.
 */
CLIENT *
__libc_clntudp_bufcreate (struct sockaddr_in *raddr, u_long program,
			  u_long version, struct timeval wait, int *sockp,
			  u_int sendsz, u_int recvsz, int flags)
{
  CLIENT *cl;
  struct cu_data *cu = NULL;
  struct rpc_msg call_msg;

  cl = (CLIENT *) mem_alloc (sizeof (CLIENT));
  sendsz = ((sendsz + 3) / 4) * 4;
  recvsz = ((recvsz + 3) / 4) * 4;
  cu = (struct cu_data *) mem_alloc (sizeof (*cu) + sendsz + recvsz);
  if (cl == NULL || cu == NULL)
    {
      struct rpc_createerr *ce = &get_rpc_createerr ();
      (void) __fxprintf (NULL, "%s: %s",
			 "clntudp_create", _("out of memory\n"));
      ce->cf_stat = RPC_SYSTEMERROR;
      ce->cf_error.re_errno = ENOMEM;
      goto fooy;
    }
  cu->cu_outbuf = &cu->cu_inbuf[recvsz];

  if (raddr->sin_port == 0)
    {
      u_short port;
      if ((port =
	   pmap_getport (raddr, program, version, IPPROTO_UDP)) == 0)
	{
	  goto fooy;
	}
      raddr->sin_port = htons (port);
    }
  cl->cl_ops = (struct clnt_ops *) &udp_ops;
  cl->cl_private = (caddr_t) cu;
  cu->cu_raddr = *raddr;
  cu->cu_rlen = sizeof (cu->cu_raddr);
  cu->cu_wait = wait;
  cu->cu_total.tv_sec = -1;
  cu->cu_total.tv_usec = -1;
  cu->cu_sendsz = sendsz;
  cu->cu_recvsz = recvsz;
  call_msg.rm_xid = _create_xid ();
  call_msg.rm_direction = CALL;
  call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
  call_msg.rm_call.cb_prog = program;
  call_msg.rm_call.cb_vers = version;
  xdrmem_create (&(cu->cu_outxdrs), cu->cu_outbuf, sendsz, XDR_ENCODE);
  if (!xdr_callhdr (&(cu->cu_outxdrs), &call_msg))
    {
      goto fooy;
    }
  cu->cu_xdrpos = XDR_GETPOS (&(cu->cu_outxdrs));
  if (*sockp < 0)
    {
      *sockp = __socket (AF_INET, SOCK_DGRAM|SOCK_NONBLOCK|flags, IPPROTO_UDP);
      if (__glibc_unlikely (*sockp < 0))
	{
	  struct rpc_createerr *ce = &get_rpc_createerr ();
	  ce->cf_stat = RPC_SYSTEMERROR;
	  ce->cf_error.re_errno = errno;
	  goto fooy;
	}
      /* attempt to bind to prov port */
      (void) bindresvport (*sockp, (struct sockaddr_in *) 0);
#ifdef IP_RECVERR
      {
	int on = 1;
	__setsockopt (*sockp, SOL_IP, IP_RECVERR, &on, sizeof(on));
      }
#endif
      cu->cu_closeit = TRUE;
    }
  else
    {
      cu->cu_closeit = FALSE;
    }
  cu->cu_sock = *sockp;
  cl->cl_auth = authnone_create ();
  return cl;
fooy:
  if (cu)
    mem_free ((caddr_t) cu, sizeof (*cu) + sendsz + recvsz);
  if (cl)
    mem_free ((caddr_t) cl, sizeof (CLIENT));
  return (CLIENT *) NULL;
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (__libc_clntudp_bufcreate)
#else
libc_hidden_nolink_sunrpc (__libc_clntudp_bufcreate, GLIBC_PRIVATE)
#endif

CLIENT *
clntudp_bufcreate (struct sockaddr_in *raddr, u_long program, u_long version,
		   struct timeval wait, int *sockp, u_int sendsz,
		   u_int recvsz)
{
  return __libc_clntudp_bufcreate (raddr, program, version, wait,
				   sockp, sendsz, recvsz, 0);
}
libc_hidden_nolink_sunrpc (clntudp_bufcreate, GLIBC_2_0)

CLIENT *
clntudp_create (struct sockaddr_in *raddr, u_long program, u_long version,
		struct timeval wait, int *sockp)
{
  return __libc_clntudp_bufcreate (raddr, program, version, wait,
				   sockp, UDPMSGSIZE, UDPMSGSIZE, 0);
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (clntudp_create)
#else
libc_hidden_nolink_sunrpc (clntudp_create, GLIBC_2_0)
#endif

static int
is_network_up (int sock)
{
  struct ifaddrs *ifa;

  if (getifaddrs (&ifa) != 0)
    return 0;

  struct ifaddrs *run = ifa;
  while (run != NULL)
    {
      if ((run->ifa_flags & IFF_UP) != 0
	  && run->ifa_addr != NULL
	  && run->ifa_addr->sa_family == AF_INET)
	break;

      run = run->ifa_next;
    }

  freeifaddrs (ifa);

  return run != NULL;
}

static enum clnt_stat
clntudp_call (/* client handle */
	      CLIENT *cl,
	      /* procedure number */
	      u_long proc,
	      /* xdr routine for args */
	      xdrproc_t xargs,
	      /* pointer to args */
	      caddr_t argsp,
	      /* xdr routine for results */
	      xdrproc_t xresults,
	      /* pointer to results */
	      caddr_t resultsp,
	      /* seconds to wait before giving up */
	      struct timeval utimeout)
{
  struct cu_data *cu = (struct cu_data *) cl->cl_private;
  XDR *xdrs;
  int outlen = 0;
  int inlen;
  socklen_t fromlen;
  struct pollfd fd;
  struct sockaddr_in from;
  struct rpc_msg reply_msg;
  XDR reply_xdrs;
  bool_t ok;
  int nrefreshes = 2;		/* number of times to refresh cred */
  int anyup;			/* any network interface up */

  struct deadline_current_time current_time = __deadline_current_time ();
  struct deadline total_deadline; /* Determined once by overall timeout.  */
  struct deadline response_deadline; /* Determined anew for each query.  */

  /* Choose the timeout value.  For non-sending usage (xargs == NULL),
     the total deadline does not matter, only cu->cu_wait is used
     below.  */
  if (xargs != NULL)
    {
      struct timeval tv;
      if (cu->cu_total.tv_usec == -1)
	/* Use supplied timeout.  */
	tv = utimeout;
      else
	/* Use default timeout.  */
	tv = cu->cu_total;
      if (!__is_timeval_valid_timeout (tv))
	return (cu->cu_error.re_status = RPC_TIMEDOUT);
      total_deadline = __deadline_from_timeval (current_time, tv);
    }

  /* Guard against bad timeout specification.  */
  if (!__is_timeval_valid_timeout (cu->cu_wait))
    return (cu->cu_error.re_status = RPC_TIMEDOUT);

call_again:
  xdrs = &(cu->cu_outxdrs);
  if (xargs == NULL)
    goto get_reply;
  xdrs->x_op = XDR_ENCODE;
  XDR_SETPOS (xdrs, cu->cu_xdrpos);
  /*
   * the transaction is the first thing in the out buffer
   */
  (*(uint32_t *) (cu->cu_outbuf))++;
  if ((!XDR_PUTLONG (xdrs, (long *) &proc)) ||
      (!AUTH_MARSHALL (cl->cl_auth, xdrs)) ||
      (!(*xargs) (xdrs, argsp)))
    return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
  outlen = (int) XDR_GETPOS (xdrs);

send_again:
  if (__sendto (cu->cu_sock, cu->cu_outbuf, outlen, 0,
		(struct sockaddr *) &(cu->cu_raddr), cu->cu_rlen)
      != outlen)
    {
      cu->cu_error.re_errno = errno;
      return (cu->cu_error.re_status = RPC_CANTSEND);
    }

  /* sendto may have blocked, so recompute the current time.  */
  current_time = __deadline_current_time ();
 get_reply:
  response_deadline = __deadline_from_timeval (current_time, cu->cu_wait);

  reply_msg.acpted_rply.ar_verf = _null_auth;
  reply_msg.acpted_rply.ar_results.where = resultsp;
  reply_msg.acpted_rply.ar_results.proc = xresults;
  fd.fd = cu->cu_sock;
  fd.events = POLLIN;
  anyup = 0;

  /* Per-response retry loop.  current_time must be up-to-date at the
     top of the loop.  */
  for (;;)
    {
      int milliseconds;
      if (xargs != NULL)
	{
	  if (__deadline_elapsed (current_time, total_deadline))
	    /* Overall timeout expired.  */
	    return (cu->cu_error.re_status = RPC_TIMEDOUT);
	  milliseconds = __deadline_to_ms
	    (current_time, __deadline_first (total_deadline,
					     response_deadline));
	  if (milliseconds == 0)
	    /* Per-query timeout expired.  */
	    goto send_again;
	}
      else
	{
	  /* xatgs == NULL.  Collect a response without sending a
	     query.  In this mode, we need to ignore the total
	     deadline.  */
	  milliseconds = __deadline_to_ms (current_time, response_deadline);
	  if (milliseconds == 0)
	    /* Cannot send again, so bail out.  */
	    return (cu->cu_error.re_status = RPC_CANTSEND);
	}

      switch (__poll (&fd, 1, milliseconds))
	{

	case 0:
	  if (anyup == 0)
	    {
	      anyup = is_network_up (cu->cu_sock);
	      if (!anyup)
		return (cu->cu_error.re_status = RPC_CANTRECV);
	    }
	  goto next_response;
	case -1:
	  if (errno == EINTR)
	    goto next_response;
	  cu->cu_error.re_errno = errno;
	  return (cu->cu_error.re_status = RPC_CANTRECV);
	}
#ifdef IP_RECVERR
      if (fd.revents & POLLERR)
	{
	  struct msghdr msg;
	  struct cmsghdr *cmsg;
	  struct sock_extended_err *e;
	  struct sockaddr_in err_addr;
	  struct iovec iov;
	  char *cbuf = malloc (outlen + 256);
	  int ret;

	  if (cbuf == NULL)
	    {
	      cu->cu_error.re_errno = errno;
	      return (cu->cu_error.re_status = RPC_CANTRECV);
	    }

	  iov.iov_base = cbuf + 256;
	  iov.iov_len = outlen;
	  msg.msg_name = (void *) &err_addr;
	  msg.msg_namelen = sizeof (err_addr);
	  msg.msg_iov = &iov;
	  msg.msg_iovlen = 1;
	  msg.msg_flags = 0;
	  msg.msg_control = cbuf;
	  msg.msg_controllen = 256;
	  ret = __recvmsg (cu->cu_sock, &msg, MSG_ERRQUEUE);
	  if (ret >= 0
	      && memcmp (cbuf + 256, cu->cu_outbuf, ret) == 0
	      && (msg.msg_flags & MSG_ERRQUEUE)
	      && ((msg.msg_namelen == 0
		   && ret >= 12)
		  || (msg.msg_namelen == sizeof (err_addr)
		      && err_addr.sin_family == AF_INET
		      && memcmp (&err_addr.sin_addr, &cu->cu_raddr.sin_addr,
				 sizeof (err_addr.sin_addr)) == 0
		      && err_addr.sin_port == cu->cu_raddr.sin_port)))
	    for (cmsg = CMSG_FIRSTHDR (&msg); cmsg;
		 cmsg = CMSG_NXTHDR (&msg, cmsg))
	      if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_RECVERR)
		{
		  e = (struct sock_extended_err *) CMSG_DATA(cmsg);
		  cu->cu_error.re_errno = e->ee_errno;
		  free (cbuf);
		  return (cu->cu_error.re_status = RPC_CANTRECV);
		}
	  free (cbuf);
	}
#endif
      do
	{
	  fromlen = sizeof (struct sockaddr);
	  inlen = __recvfrom (cu->cu_sock, cu->cu_inbuf,
			      (int) cu->cu_recvsz, MSG_DONTWAIT,
			      (struct sockaddr *) &from, &fromlen);
	}
      while (inlen < 0 && errno == EINTR);
      if (inlen < 0)
	{
	  if (errno == EWOULDBLOCK)
	    goto next_response;
	  cu->cu_error.re_errno = errno;
	  return (cu->cu_error.re_status = RPC_CANTRECV);
	}
      /* Accept the response if the packet is sufficiently long and
	 the transaction ID matches the query (if available).  */
      if (inlen >= 4
	  && (xargs == NULL
	      || memcmp (cu->cu_inbuf, cu->cu_outbuf,
			 sizeof (u_int32_t)) == 0))
	break;

    next_response:
      /* Update the current time because poll and recvmsg waited for
	 an unknown time.  */
      current_time = __deadline_current_time ();
    }

  /*
   * now decode and validate the response
   */
  xdrmem_create (&reply_xdrs, cu->cu_inbuf, (u_int) inlen, XDR_DECODE);
  ok = xdr_replymsg (&reply_xdrs, &reply_msg);
  /* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
  if (ok)
    {
      _seterr_reply (&reply_msg, &(cu->cu_error));
      if (cu->cu_error.re_status == RPC_SUCCESS)
	{
	  if (!AUTH_VALIDATE (cl->cl_auth,
			      &reply_msg.acpted_rply.ar_verf))
	    {
	      cu->cu_error.re_status = RPC_AUTHERROR;
	      cu->cu_error.re_why = AUTH_INVALIDRESP;
	    }
	  if (reply_msg.acpted_rply.ar_verf.oa_base != NULL)
	    {
	      xdrs->x_op = XDR_FREE;
	      (void) xdr_opaque_auth (xdrs, &(reply_msg.acpted_rply.ar_verf));
	    }
	}			/* end successful completion */
      else
	{
	  /* maybe our credentials need to be refreshed ... */
	  if (nrefreshes > 0 && AUTH_REFRESH (cl->cl_auth))
	    {
	      nrefreshes--;
	      goto call_again;
	    }
	}			/* end of unsuccessful completion */
    }				/* end of valid reply message */
  else
    {
      cu->cu_error.re_status = RPC_CANTDECODERES;
    }
  return cu->cu_error.re_status;
}

static void
clntudp_geterr (CLIENT *cl, struct rpc_err *errp)
{
  struct cu_data *cu = (struct cu_data *) cl->cl_private;

  *errp = cu->cu_error;
}


static bool_t
clntudp_freeres (CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
{
  struct cu_data *cu = (struct cu_data *) cl->cl_private;
  XDR *xdrs = &(cu->cu_outxdrs);

  xdrs->x_op = XDR_FREE;
  return (*xdr_res) (xdrs, res_ptr);
}

static void
clntudp_abort (void)
{
}

static bool_t
clntudp_control (CLIENT *cl, int request, char *info)
{
  struct cu_data *cu = (struct cu_data *) cl->cl_private;
  u_long ul;
  u_int32_t ui32;

  switch (request)
    {
    case CLSET_FD_CLOSE:
      cu->cu_closeit = TRUE;
      break;
    case CLSET_FD_NCLOSE:
      cu->cu_closeit = FALSE;
      break;
    case CLSET_TIMEOUT:
      cu->cu_total = *(struct timeval *) info;
      break;
    case CLGET_TIMEOUT:
      *(struct timeval *) info = cu->cu_total;
      break;
    case CLSET_RETRY_TIMEOUT:
      cu->cu_wait = *(struct timeval *) info;
      break;
    case CLGET_RETRY_TIMEOUT:
      *(struct timeval *) info = cu->cu_wait;
      break;
    case CLGET_SERVER_ADDR:
      *(struct sockaddr_in *) info = cu->cu_raddr;
      break;
    case CLGET_FD:
      *(int *)info = cu->cu_sock;
      break;
    case CLGET_XID:
      /*
       * use the knowledge that xid is the
       * first element in the call structure *.
       * This will get the xid of the PREVIOUS call
       */
      memcpy (&ui32, cu->cu_outbuf, sizeof (ui32));
      ul = ntohl (ui32);
      memcpy (info, &ul, sizeof (ul));
      break;
    case CLSET_XID:
      /* This will set the xid of the NEXT call */
      memcpy (&ul, info, sizeof (ul));
      ui32 = htonl (ul - 1);
      memcpy (cu->cu_outbuf, &ui32, sizeof (ui32));
      /* decrement by 1 as clntudp_call() increments once */
      break;
    case CLGET_VERS:
      /*
       * This RELIES on the information that, in the call body,
       * the version number field is the fifth field from the
       * beginning of the RPC header. MUST be changed if the
       * call_struct is changed
       */
      memcpy (&ui32, cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT, sizeof (ui32));
      ul = ntohl (ui32);
      memcpy (info, &ul, sizeof (ul));
      break;
    case CLSET_VERS:
      memcpy (&ul, info, sizeof (ul));
      ui32 = htonl (ul);
      memcpy (cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32));
      break;
    case CLGET_PROG:
      /*
       * This RELIES on the information that, in the call body,
       * the program number field is the  field from the
       * beginning of the RPC header. MUST be changed if the
       * call_struct is changed
       */
      memcpy (&ui32, cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT, sizeof (ui32));
      ul = ntohl (ui32);
      memcpy (info, &ul, sizeof (ul));
      break;
    case CLSET_PROG:
      memcpy (&ul, info, sizeof (ul));
      ui32 = htonl (ul);
      memcpy (cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32));
      break;
    /* The following are only possible with TI-RPC */
    case CLGET_SVC_ADDR:
    case CLSET_SVC_ADDR:
    case CLSET_PUSH_TIMOD:
    case CLSET_POP_TIMOD:
    default:
      return FALSE;
    }
  return TRUE;
}

static void
clntudp_destroy (CLIENT *cl)
{
  struct cu_data *cu = (struct cu_data *) cl->cl_private;

  if (cu->cu_closeit)
    {
      (void) __close (cu->cu_sock);
    }
  XDR_DESTROY (&(cu->cu_outxdrs));
  mem_free ((caddr_t) cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
  mem_free ((caddr_t) cl, sizeof (CLIENT));
}