1/*
2 * clnt_udp.c, Implements a UDP/IP based, client side RPC.
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 <stdio.h>
35#include <unistd.h>
36#include <libintl.h>
37#include <rpc/rpc.h>
38#include <rpc/xdr.h>
39#include <rpc/clnt.h>
40#include <sys/poll.h>
41#include <sys/socket.h>
42#include <sys/ioctl.h>
43#include <netdb.h>
44#include <errno.h>
45#include <stdint.h>
46#include <rpc/pmap_clnt.h>
47#include <net/if.h>
48#include <ifaddrs.h>
49#include <wchar.h>
50#include <fcntl.h>
51
52#ifdef IP_RECVERR
53#include <errqueue.h>
54#include <sys/uio.h>
55#endif
56
57#include <kernel-features.h>
58
59extern u_long _create_xid (void);
60
61/*
62 * UDP bases client side rpc operations
63 */
64static enum clnt_stat clntudp_call (CLIENT *, u_long, xdrproc_t, caddr_t,
65 xdrproc_t, caddr_t, struct timeval);
66static void clntudp_abort (void);
67static void clntudp_geterr (CLIENT *, struct rpc_err *);
68static bool_t clntudp_freeres (CLIENT *, xdrproc_t, caddr_t);
69static bool_t clntudp_control (CLIENT *, int, char *);
70static void clntudp_destroy (CLIENT *);
71
72static const struct clnt_ops udp_ops =
73{
74 clntudp_call,
75 clntudp_abort,
76 clntudp_geterr,
77 clntudp_freeres,
78 clntudp_destroy,
79 clntudp_control
80};
81
82/*
83 * Private data kept per client handle
84 */
85struct cu_data
86 {
87 int cu_sock;
88 bool_t cu_closeit;
89 struct sockaddr_in cu_raddr;
90 int cu_rlen;
91 struct timeval cu_wait;
92 struct timeval cu_total;
93 struct rpc_err cu_error;
94 XDR cu_outxdrs;
95 u_int cu_xdrpos;
96 u_int cu_sendsz;
97 char *cu_outbuf;
98 u_int cu_recvsz;
99 char cu_inbuf[1];
100 };
101
102/*
103 * Create a UDP based client handle.
104 * If *sockp<0, *sockp is set to a newly created UPD socket.
105 * If raddr->sin_port is 0 a binder on the remote machine
106 * is consulted for the correct port number.
107 * NB: It is the clients responsibility to close *sockp.
108 * NB: The rpch->cl_auth is initialized to null authentication.
109 * Caller may wish to set this something more useful.
110 *
111 * wait is the amount of time used between retransmitting a call if
112 * no response has been heard; retransmission occurs until the actual
113 * rpc call times out.
114 *
115 * sendsz and recvsz are the maximum allowable packet sizes that can be
116 * sent and received.
117 */
118CLIENT *
119__libc_clntudp_bufcreate (struct sockaddr_in *raddr, u_long program,
120 u_long version, struct timeval wait, int *sockp,
121 u_int sendsz, u_int recvsz, int flags)
122{
123 CLIENT *cl;
124 struct cu_data *cu = NULL;
125 struct rpc_msg call_msg;
126
127 cl = (CLIENT *) mem_alloc (sizeof (CLIENT));
128 sendsz = ((sendsz + 3) / 4) * 4;
129 recvsz = ((recvsz + 3) / 4) * 4;
130 cu = (struct cu_data *) mem_alloc (sizeof (*cu) + sendsz + recvsz);
131 if (cl == NULL || cu == NULL)
132 {
133 struct rpc_createerr *ce = &get_rpc_createerr ();
134 (void) __fxprintf (NULL, "%s: %s",
135 "clntudp_create", _("out of memory\n"));
136 ce->cf_stat = RPC_SYSTEMERROR;
137 ce->cf_error.re_errno = ENOMEM;
138 goto fooy;
139 }
140 cu->cu_outbuf = &cu->cu_inbuf[recvsz];
141
142 if (raddr->sin_port == 0)
143 {
144 u_short port;
145 if ((port =
146 pmap_getport (raddr, program, version, IPPROTO_UDP)) == 0)
147 {
148 goto fooy;
149 }
150 raddr->sin_port = htons (port);
151 }
152 cl->cl_ops = (struct clnt_ops *) &udp_ops;
153 cl->cl_private = (caddr_t) cu;
154 cu->cu_raddr = *raddr;
155 cu->cu_rlen = sizeof (cu->cu_raddr);
156 cu->cu_wait = wait;
157 cu->cu_total.tv_sec = -1;
158 cu->cu_total.tv_usec = -1;
159 cu->cu_sendsz = sendsz;
160 cu->cu_recvsz = recvsz;
161 call_msg.rm_xid = _create_xid ();
162 call_msg.rm_direction = CALL;
163 call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
164 call_msg.rm_call.cb_prog = program;
165 call_msg.rm_call.cb_vers = version;
166 xdrmem_create (&(cu->cu_outxdrs), cu->cu_outbuf, sendsz, XDR_ENCODE);
167 if (!xdr_callhdr (&(cu->cu_outxdrs), &call_msg))
168 {
169 goto fooy;
170 }
171 cu->cu_xdrpos = XDR_GETPOS (&(cu->cu_outxdrs));
172 if (*sockp < 0)
173 {
174 *sockp = __socket (AF_INET, SOCK_DGRAM|SOCK_NONBLOCK|flags, IPPROTO_UDP);
175 if (__glibc_unlikely (*sockp < 0))
176 {
177 struct rpc_createerr *ce = &get_rpc_createerr ();
178 ce->cf_stat = RPC_SYSTEMERROR;
179 ce->cf_error.re_errno = errno;
180 goto fooy;
181 }
182 /* attempt to bind to prov port */
183 (void) bindresvport (*sockp, (struct sockaddr_in *) 0);
184#ifdef IP_RECVERR
185 {
186 int on = 1;
187 __setsockopt (*sockp, SOL_IP, IP_RECVERR, &on, sizeof(on));
188 }
189#endif
190 cu->cu_closeit = TRUE;
191 }
192 else
193 {
194 cu->cu_closeit = FALSE;
195 }
196 cu->cu_sock = *sockp;
197 cl->cl_auth = authnone_create ();
198 return cl;
199fooy:
200 if (cu)
201 mem_free ((caddr_t) cu, sizeof (*cu) + sendsz + recvsz);
202 if (cl)
203 mem_free ((caddr_t) cl, sizeof (CLIENT));
204 return (CLIENT *) NULL;
205}
206#ifdef EXPORT_RPC_SYMBOLS
207libc_hidden_def (__libc_clntudp_bufcreate)
208#else
209libc_hidden_nolink_sunrpc (__libc_clntudp_bufcreate, GLIBC_PRIVATE)
210#endif
211
212CLIENT *
213clntudp_bufcreate (struct sockaddr_in *raddr, u_long program, u_long version,
214 struct timeval wait, int *sockp, u_int sendsz,
215 u_int recvsz)
216{
217 return __libc_clntudp_bufcreate (raddr, program, version, wait,
218 sockp, sendsz, recvsz, 0);
219}
220libc_hidden_nolink_sunrpc (clntudp_bufcreate, GLIBC_2_0)
221
222CLIENT *
223clntudp_create (struct sockaddr_in *raddr, u_long program, u_long version,
224 struct timeval wait, int *sockp)
225{
226 return __libc_clntudp_bufcreate (raddr, program, version, wait,
227 sockp, UDPMSGSIZE, UDPMSGSIZE, 0);
228}
229#ifdef EXPORT_RPC_SYMBOLS
230libc_hidden_def (clntudp_create)
231#else
232libc_hidden_nolink_sunrpc (clntudp_create, GLIBC_2_0)
233#endif
234
235static int
236is_network_up (int sock)
237{
238 struct ifaddrs *ifa;
239
240 if (getifaddrs (&ifa) != 0)
241 return 0;
242
243 struct ifaddrs *run = ifa;
244 while (run != NULL)
245 {
246 if ((run->ifa_flags & IFF_UP) != 0
247 && run->ifa_addr != NULL
248 && run->ifa_addr->sa_family == AF_INET)
249 break;
250
251 run = run->ifa_next;
252 }
253
254 freeifaddrs (ifa);
255
256 return run != NULL;
257}
258
259static enum clnt_stat
260clntudp_call (/* client handle */
261 CLIENT *cl,
262 /* procedure number */
263 u_long proc,
264 /* xdr routine for args */
265 xdrproc_t xargs,
266 /* pointer to args */
267 caddr_t argsp,
268 /* xdr routine for results */
269 xdrproc_t xresults,
270 /* pointer to results */
271 caddr_t resultsp,
272 /* seconds to wait before giving up */
273 struct timeval utimeout)
274{
275 struct cu_data *cu = (struct cu_data *) cl->cl_private;
276 XDR *xdrs;
277 int outlen = 0;
278 int inlen;
279 socklen_t fromlen;
280 struct pollfd fd;
281 int milliseconds = (cu->cu_wait.tv_sec * 1000) +
282 (cu->cu_wait.tv_usec / 1000);
283 struct sockaddr_in from;
284 struct rpc_msg reply_msg;
285 XDR reply_xdrs;
286 struct timeval time_waited;
287 bool_t ok;
288 int nrefreshes = 2; /* number of times to refresh cred */
289 struct timeval timeout;
290 int anyup; /* any network interface up */
291
292 if (cu->cu_total.tv_usec == -1)
293 {
294 timeout = utimeout; /* use supplied timeout */
295 }
296 else
297 {
298 timeout = cu->cu_total; /* use default timeout */
299 }
300
301 time_waited.tv_sec = 0;
302 time_waited.tv_usec = 0;
303call_again:
304 xdrs = &(cu->cu_outxdrs);
305 if (xargs == NULL)
306 goto get_reply;
307 xdrs->x_op = XDR_ENCODE;
308 XDR_SETPOS (xdrs, cu->cu_xdrpos);
309 /*
310 * the transaction is the first thing in the out buffer
311 */
312 (*(uint32_t *) (cu->cu_outbuf))++;
313 if ((!XDR_PUTLONG (xdrs, (long *) &proc)) ||
314 (!AUTH_MARSHALL (cl->cl_auth, xdrs)) ||
315 (!(*xargs) (xdrs, argsp)))
316 return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
317 outlen = (int) XDR_GETPOS (xdrs);
318
319send_again:
320 if (__sendto (cu->cu_sock, cu->cu_outbuf, outlen, 0,
321 (struct sockaddr *) &(cu->cu_raddr), cu->cu_rlen)
322 != outlen)
323 {
324 cu->cu_error.re_errno = errno;
325 return (cu->cu_error.re_status = RPC_CANTSEND);
326 }
327
328 /*
329 * Hack to provide rpc-based message passing
330 */
331 if (timeout.tv_sec == 0 && timeout.tv_usec == 0)
332 {
333 return (cu->cu_error.re_status = RPC_TIMEDOUT);
334 }
335 get_reply:
336 /*
337 * sub-optimal code appears here because we have
338 * some clock time to spare while the packets are in flight.
339 * (We assume that this is actually only executed once.)
340 */
341 reply_msg.acpted_rply.ar_verf = _null_auth;
342 reply_msg.acpted_rply.ar_results.where = resultsp;
343 reply_msg.acpted_rply.ar_results.proc = xresults;
344 fd.fd = cu->cu_sock;
345 fd.events = POLLIN;
346 anyup = 0;
347 for (;;)
348 {
349 switch (__poll (&fd, 1, milliseconds))
350 {
351
352 case 0:
353 if (anyup == 0)
354 {
355 anyup = is_network_up (cu->cu_sock);
356 if (!anyup)
357 return (cu->cu_error.re_status = RPC_CANTRECV);
358 }
359
360 time_waited.tv_sec += cu->cu_wait.tv_sec;
361 time_waited.tv_usec += cu->cu_wait.tv_usec;
362 while (time_waited.tv_usec >= 1000000)
363 {
364 time_waited.tv_sec++;
365 time_waited.tv_usec -= 1000000;
366 }
367 if ((time_waited.tv_sec < timeout.tv_sec) ||
368 ((time_waited.tv_sec == timeout.tv_sec) &&
369 (time_waited.tv_usec < timeout.tv_usec)))
370 goto send_again;
371 return (cu->cu_error.re_status = RPC_TIMEDOUT);
372
373 /*
374 * buggy in other cases because time_waited is not being
375 * updated.
376 */
377 case -1:
378 if (errno == EINTR)
379 continue;
380 cu->cu_error.re_errno = errno;
381 return (cu->cu_error.re_status = RPC_CANTRECV);
382 }
383#ifdef IP_RECVERR
384 if (fd.revents & POLLERR)
385 {
386 struct msghdr msg;
387 struct cmsghdr *cmsg;
388 struct sock_extended_err *e;
389 struct sockaddr_in err_addr;
390 struct iovec iov;
391 char *cbuf = (char *) alloca (outlen + 256);
392 int ret;
393
394 iov.iov_base = cbuf + 256;
395 iov.iov_len = outlen;
396 msg.msg_name = (void *) &err_addr;
397 msg.msg_namelen = sizeof (err_addr);
398 msg.msg_iov = &iov;
399 msg.msg_iovlen = 1;
400 msg.msg_flags = 0;
401 msg.msg_control = cbuf;
402 msg.msg_controllen = 256;
403 ret = __recvmsg (cu->cu_sock, &msg, MSG_ERRQUEUE);
404 if (ret >= 0
405 && memcmp (cbuf + 256, cu->cu_outbuf, ret) == 0
406 && (msg.msg_flags & MSG_ERRQUEUE)
407 && ((msg.msg_namelen == 0
408 && ret >= 12)
409 || (msg.msg_namelen == sizeof (err_addr)
410 && err_addr.sin_family == AF_INET
411 && memcmp (&err_addr.sin_addr, &cu->cu_raddr.sin_addr,
412 sizeof (err_addr.sin_addr)) == 0
413 && err_addr.sin_port == cu->cu_raddr.sin_port)))
414 for (cmsg = CMSG_FIRSTHDR (&msg); cmsg;
415 cmsg = CMSG_NXTHDR (&msg, cmsg))
416 if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_RECVERR)
417 {
418 e = (struct sock_extended_err *) CMSG_DATA(cmsg);
419 cu->cu_error.re_errno = e->ee_errno;
420 return (cu->cu_error.re_status = RPC_CANTRECV);
421 }
422 }
423#endif
424 do
425 {
426 fromlen = sizeof (struct sockaddr);
427 inlen = __recvfrom (cu->cu_sock, cu->cu_inbuf,
428 (int) cu->cu_recvsz, MSG_DONTWAIT,
429 (struct sockaddr *) &from, &fromlen);
430 }
431 while (inlen < 0 && errno == EINTR);
432 if (inlen < 0)
433 {
434 if (errno == EWOULDBLOCK)
435 continue;
436 cu->cu_error.re_errno = errno;
437 return (cu->cu_error.re_status = RPC_CANTRECV);
438 }
439 if (inlen < 4)
440 continue;
441
442 /* see if reply transaction id matches sent id.
443 Don't do this if we only wait for a replay */
444 if (xargs != NULL
445 && memcmp (cu->cu_inbuf, cu->cu_outbuf, sizeof (u_int32_t)) != 0)
446 continue;
447 /* we now assume we have the proper reply */
448 break;
449 }
450
451 /*
452 * now decode and validate the response
453 */
454 xdrmem_create (&reply_xdrs, cu->cu_inbuf, (u_int) inlen, XDR_DECODE);
455 ok = xdr_replymsg (&reply_xdrs, &reply_msg);
456 /* XDR_DESTROY(&reply_xdrs); save a few cycles on noop destroy */
457 if (ok)
458 {
459 _seterr_reply (&reply_msg, &(cu->cu_error));
460 if (cu->cu_error.re_status == RPC_SUCCESS)
461 {
462 if (!AUTH_VALIDATE (cl->cl_auth,
463 &reply_msg.acpted_rply.ar_verf))
464 {
465 cu->cu_error.re_status = RPC_AUTHERROR;
466 cu->cu_error.re_why = AUTH_INVALIDRESP;
467 }
468 if (reply_msg.acpted_rply.ar_verf.oa_base != NULL)
469 {
470 xdrs->x_op = XDR_FREE;
471 (void) xdr_opaque_auth (xdrs, &(reply_msg.acpted_rply.ar_verf));
472 }
473 } /* end successful completion */
474 else
475 {
476 /* maybe our credentials need to be refreshed ... */
477 if (nrefreshes > 0 && AUTH_REFRESH (cl->cl_auth))
478 {
479 nrefreshes--;
480 goto call_again;
481 }
482 } /* end of unsuccessful completion */
483 } /* end of valid reply message */
484 else
485 {
486 cu->cu_error.re_status = RPC_CANTDECODERES;
487 }
488 return cu->cu_error.re_status;
489}
490
491static void
492clntudp_geterr (CLIENT *cl, struct rpc_err *errp)
493{
494 struct cu_data *cu = (struct cu_data *) cl->cl_private;
495
496 *errp = cu->cu_error;
497}
498
499
500static bool_t
501clntudp_freeres (CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
502{
503 struct cu_data *cu = (struct cu_data *) cl->cl_private;
504 XDR *xdrs = &(cu->cu_outxdrs);
505
506 xdrs->x_op = XDR_FREE;
507 return (*xdr_res) (xdrs, res_ptr);
508}
509
510static void
511clntudp_abort (void)
512{
513}
514
515static bool_t
516clntudp_control (CLIENT *cl, int request, char *info)
517{
518 struct cu_data *cu = (struct cu_data *) cl->cl_private;
519 u_long ul;
520 u_int32_t ui32;
521
522 switch (request)
523 {
524 case CLSET_FD_CLOSE:
525 cu->cu_closeit = TRUE;
526 break;
527 case CLSET_FD_NCLOSE:
528 cu->cu_closeit = FALSE;
529 break;
530 case CLSET_TIMEOUT:
531 cu->cu_total = *(struct timeval *) info;
532 break;
533 case CLGET_TIMEOUT:
534 *(struct timeval *) info = cu->cu_total;
535 break;
536 case CLSET_RETRY_TIMEOUT:
537 cu->cu_wait = *(struct timeval *) info;
538 break;
539 case CLGET_RETRY_TIMEOUT:
540 *(struct timeval *) info = cu->cu_wait;
541 break;
542 case CLGET_SERVER_ADDR:
543 *(struct sockaddr_in *) info = cu->cu_raddr;
544 break;
545 case CLGET_FD:
546 *(int *)info = cu->cu_sock;
547 break;
548 case CLGET_XID:
549 /*
550 * use the knowledge that xid is the
551 * first element in the call structure *.
552 * This will get the xid of the PREVIOUS call
553 */
554 memcpy (&ui32, cu->cu_outbuf, sizeof (ui32));
555 ul = ntohl (ui32);
556 memcpy (info, &ul, sizeof (ul));
557 break;
558 case CLSET_XID:
559 /* This will set the xid of the NEXT call */
560 memcpy (&ul, info, sizeof (ul));
561 ui32 = htonl (ul - 1);
562 memcpy (cu->cu_outbuf, &ui32, sizeof (ui32));
563 /* decrement by 1 as clntudp_call() increments once */
564 break;
565 case CLGET_VERS:
566 /*
567 * This RELIES on the information that, in the call body,
568 * the version number field is the fifth field from the
569 * beginning of the RPC header. MUST be changed if the
570 * call_struct is changed
571 */
572 memcpy (&ui32, cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT, sizeof (ui32));
573 ul = ntohl (ui32);
574 memcpy (info, &ul, sizeof (ul));
575 break;
576 case CLSET_VERS:
577 memcpy (&ul, info, sizeof (ul));
578 ui32 = htonl (ul);
579 memcpy (cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32));
580 break;
581 case CLGET_PROG:
582 /*
583 * This RELIES on the information that, in the call body,
584 * the program number field is the field from the
585 * beginning of the RPC header. MUST be changed if the
586 * call_struct is changed
587 */
588 memcpy (&ui32, cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT, sizeof (ui32));
589 ul = ntohl (ui32);
590 memcpy (info, &ul, sizeof (ul));
591 break;
592 case CLSET_PROG:
593 memcpy (&ul, info, sizeof (ul));
594 ui32 = htonl (ul);
595 memcpy (cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32));
596 break;
597 /* The following are only possible with TI-RPC */
598 case CLGET_SVC_ADDR:
599 case CLSET_SVC_ADDR:
600 case CLSET_PUSH_TIMOD:
601 case CLSET_POP_TIMOD:
602 default:
603 return FALSE;
604 }
605 return TRUE;
606}
607
608static void
609clntudp_destroy (CLIENT *cl)
610{
611 struct cu_data *cu = (struct cu_data *) cl->cl_private;
612
613 if (cu->cu_closeit)
614 {
615 (void) __close (cu->cu_sock);
616 }
617 XDR_DESTROY (&(cu->cu_outxdrs));
618 mem_free ((caddr_t) cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
619 mem_free ((caddr_t) cl, sizeof (CLIENT));
620}
621