1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
5 * Authors: Doug Rabson <dfr@rabson.org>
6 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/limits.h>
34 #include <sys/lock.h>
35 #include <sys/malloc.h>
36 #include <sys/mbuf.h>
37 #include <sys/mutex.h>
38 #include <sys/pcpu.h>
39 #include <sys/proc.h>
40 #include <sys/socket.h>
41 #include <sys/socketvar.h>
42 #include <sys/time.h>
43 #include <sys/uio.h>
44
45 #include <netinet/tcp.h>
46
47 #include <rpc/rpc.h>
48 #include <rpc/rpc_com.h>
49 #include <rpc/krpc.h>
50 #include <rpc/rpcsec_tls.h>
51
52 static enum clnt_stat clnt_reconnect_call(CLIENT *, struct rpc_callextra *,
53 rpcproc_t, struct mbuf *, struct mbuf **, struct timeval);
54 static void clnt_reconnect_geterr(CLIENT *, struct rpc_err *);
55 static bool_t clnt_reconnect_freeres(CLIENT *, xdrproc_t, void *);
56 static void clnt_reconnect_abort(CLIENT *);
57 static bool_t clnt_reconnect_control(CLIENT *, u_int, void *);
58 static void clnt_reconnect_close(CLIENT *);
59 static void clnt_reconnect_destroy(CLIENT *);
60
61 static const struct clnt_ops clnt_reconnect_ops = {
62 .cl_call = clnt_reconnect_call,
63 .cl_abort = clnt_reconnect_abort,
64 .cl_geterr = clnt_reconnect_geterr,
65 .cl_freeres = clnt_reconnect_freeres,
66 .cl_close = clnt_reconnect_close,
67 .cl_destroy = clnt_reconnect_destroy,
68 .cl_control = clnt_reconnect_control
69 };
70
71 static int fake_wchan;
72
73 CLIENT *
clnt_reconnect_create(struct netconfig * nconf,struct sockaddr * svcaddr,rpcprog_t program,rpcvers_t version,size_t sendsz,size_t recvsz)74 clnt_reconnect_create(
75 struct netconfig *nconf, /* network type */
76 struct sockaddr *svcaddr, /* servers address */
77 rpcprog_t program, /* program number */
78 rpcvers_t version, /* version number */
79 size_t sendsz, /* buffer recv size */
80 size_t recvsz) /* buffer send size */
81 {
82 CLIENT *cl = NULL; /* client handle */
83 struct rc_data *rc = NULL; /* private data */
84
85 if (svcaddr == NULL) {
86 rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
87 return (NULL);
88 }
89
90 cl = mem_alloc(sizeof (CLIENT));
91 rc = mem_alloc(sizeof (*rc));
92 mtx_init(&rc->rc_lock, "rc->rc_lock", NULL, MTX_DEF);
93 (void) memcpy(&rc->rc_addr, svcaddr, (size_t)svcaddr->sa_len);
94 rc->rc_nconf = nconf;
95 rc->rc_prog = program;
96 rc->rc_vers = version;
97 rc->rc_sendsz = sendsz;
98 rc->rc_recvsz = recvsz;
99 rc->rc_timeout.tv_sec = -1;
100 rc->rc_timeout.tv_usec = -1;
101 rc->rc_retry.tv_sec = 3;
102 rc->rc_retry.tv_usec = 0;
103 rc->rc_retries = INT_MAX;
104 rc->rc_privport = FALSE;
105 rc->rc_waitchan = "rpcrecv";
106 rc->rc_intr = 0;
107 rc->rc_connecting = FALSE;
108 rc->rc_closed = FALSE;
109 rc->rc_ucred = crdup(curthread->td_ucred);
110 rc->rc_client = NULL;
111 rc->rc_tls = false;
112 rc->rc_tlscertname = NULL;
113 rc->rc_reconcall = NULL;
114 rc->rc_reconarg = NULL;
115
116 cl->cl_refs = 1;
117 cl->cl_ops = &clnt_reconnect_ops;
118 cl->cl_private = (caddr_t)(void *)rc;
119 cl->cl_auth = authnone_create();
120 cl->cl_tp = NULL;
121 cl->cl_netid = NULL;
122 return (cl);
123 }
124
125 static enum clnt_stat
clnt_reconnect_connect(CLIENT * cl)126 clnt_reconnect_connect(CLIENT *cl)
127 {
128 struct thread *td = curthread;
129 struct rc_data *rc = (struct rc_data *)cl->cl_private;
130 struct socket *so;
131 enum clnt_stat stat;
132 int error;
133 int one = 1;
134 struct ucred *oldcred;
135 CLIENT *newclient = NULL;
136 uint64_t ssl[3];
137 uint32_t reterr;
138
139 mtx_lock(&rc->rc_lock);
140 while (rc->rc_connecting) {
141 error = msleep(rc, &rc->rc_lock,
142 rc->rc_intr ? PCATCH : 0, "rpcrecon", 0);
143 if (error) {
144 mtx_unlock(&rc->rc_lock);
145 return (RPC_INTR);
146 }
147 }
148 if (rc->rc_closed) {
149 mtx_unlock(&rc->rc_lock);
150 return (RPC_CANTSEND);
151 }
152 if (rc->rc_client) {
153 mtx_unlock(&rc->rc_lock);
154 return (RPC_SUCCESS);
155 }
156
157 /*
158 * My turn to attempt a connect. The rc_connecting variable
159 * serializes the following code sequence, so it is guaranteed
160 * that rc_client will still be NULL after it is re-locked below,
161 * since that is the only place it is set non-NULL.
162 */
163 rc->rc_connecting = TRUE;
164 mtx_unlock(&rc->rc_lock);
165
166 oldcred = td->td_ucred;
167 td->td_ucred = rc->rc_ucred;
168 so = __rpc_nconf2socket(rc->rc_nconf);
169 if (!so) {
170 stat = rpc_createerr.cf_stat = RPC_TLIERROR;
171 rpc_createerr.cf_error.re_errno = 0;
172 td->td_ucred = oldcred;
173 goto out;
174 }
175
176 if (rc->rc_privport)
177 bindresvport(so, NULL);
178
179 if (rc->rc_nconf->nc_semantics == NC_TPI_CLTS)
180 newclient = clnt_dg_create(so,
181 (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
182 rc->rc_sendsz, rc->rc_recvsz);
183 else {
184 /*
185 * I do not believe a timeout of less than 1sec would make
186 * sense here since short delays can occur when a server is
187 * temporarily overloaded.
188 */
189 if (rc->rc_timeout.tv_sec > 0 && rc->rc_timeout.tv_usec >= 0) {
190 error = so_setsockopt(so, SOL_SOCKET, SO_SNDTIMEO,
191 &rc->rc_timeout, sizeof(struct timeval));
192 if (error != 0) {
193 stat = rpc_createerr.cf_stat = RPC_CANTSEND;
194 rpc_createerr.cf_error.re_errno = error;
195 td->td_ucred = oldcred;
196 goto out;
197 }
198 }
199 newclient = clnt_vc_create(so,
200 (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers,
201 rc->rc_sendsz, rc->rc_recvsz, rc->rc_intr);
202 if (rc->rc_tls && newclient != NULL) {
203 stat = rpctls_connect(newclient, rc->rc_tlscertname, so,
204 ssl, &reterr);
205 if (stat != RPC_SUCCESS || reterr != RPCTLSERR_OK) {
206 if (stat == RPC_SUCCESS)
207 stat = RPC_FAILED;
208 stat = rpc_createerr.cf_stat = stat;
209 rpc_createerr.cf_error.re_errno = 0;
210 CLNT_CLOSE(newclient);
211 CLNT_RELEASE(newclient);
212 newclient = NULL;
213 td->td_ucred = oldcred;
214 goto out;
215 }
216 }
217 if (newclient != NULL) {
218 int optval = 1;
219
220 (void)so_setsockopt(so, IPPROTO_TCP, TCP_USE_DDP,
221 &optval, sizeof(optval));
222 }
223 if (newclient != NULL && rc->rc_reconcall != NULL)
224 (*rc->rc_reconcall)(newclient, rc->rc_reconarg,
225 rc->rc_ucred);
226 }
227 td->td_ucred = oldcred;
228
229 if (!newclient) {
230 soclose(so);
231 rc->rc_err = rpc_createerr.cf_error;
232 stat = rpc_createerr.cf_stat;
233 goto out;
234 }
235
236 CLNT_CONTROL(newclient, CLSET_FD_CLOSE, 0);
237 CLNT_CONTROL(newclient, CLSET_CONNECT, &one);
238 CLNT_CONTROL(newclient, CLSET_TIMEOUT, &rc->rc_timeout);
239 CLNT_CONTROL(newclient, CLSET_RETRY_TIMEOUT, &rc->rc_retry);
240 CLNT_CONTROL(newclient, CLSET_WAITCHAN, rc->rc_waitchan);
241 CLNT_CONTROL(newclient, CLSET_INTERRUPTIBLE, &rc->rc_intr);
242 if (rc->rc_tls)
243 CLNT_CONTROL(newclient, CLSET_TLS, ssl);
244 if (rc->rc_backchannel != NULL)
245 CLNT_CONTROL(newclient, CLSET_BACKCHANNEL, rc->rc_backchannel);
246 stat = RPC_SUCCESS;
247
248 out:
249 mtx_lock(&rc->rc_lock);
250 KASSERT(rc->rc_client == NULL, ("rc_client not null"));
251 if (!rc->rc_closed) {
252 rc->rc_client = newclient;
253 newclient = NULL;
254 }
255 rc->rc_connecting = FALSE;
256 wakeup(rc);
257 mtx_unlock(&rc->rc_lock);
258
259 if (newclient) {
260 /*
261 * It has been closed, so discard the new client.
262 * nb: clnt_[dg|vc]_close()/clnt_[dg|vc]_destroy() cannot
263 * be called with the rc_lock mutex held, since they may
264 * msleep() while holding a different mutex.
265 */
266 CLNT_CLOSE(newclient);
267 CLNT_RELEASE(newclient);
268 }
269
270 return (stat);
271 }
272
273 static enum clnt_stat
clnt_reconnect_call(CLIENT * cl,struct rpc_callextra * ext,rpcproc_t proc,struct mbuf * args,struct mbuf ** resultsp,struct timeval utimeout)274 clnt_reconnect_call(
275 CLIENT *cl, /* client handle */
276 struct rpc_callextra *ext, /* call metadata */
277 rpcproc_t proc, /* procedure number */
278 struct mbuf *args, /* pointer to args */
279 struct mbuf **resultsp, /* pointer to results */
280 struct timeval utimeout)
281 {
282 struct rc_data *rc = (struct rc_data *)cl->cl_private;
283 CLIENT *client;
284 enum clnt_stat stat;
285 int tries, error;
286
287 tries = 0;
288 do {
289 mtx_lock(&rc->rc_lock);
290 if (rc->rc_closed) {
291 mtx_unlock(&rc->rc_lock);
292 return (RPC_CANTSEND);
293 }
294
295 if (!rc->rc_client) {
296 mtx_unlock(&rc->rc_lock);
297 stat = clnt_reconnect_connect(cl);
298 if (stat == RPC_SYSTEMERROR) {
299 error = tsleep(&fake_wchan,
300 rc->rc_intr ? PCATCH : 0, "rpccon", hz);
301 if (error == EINTR || error == ERESTART)
302 return (RPC_INTR);
303 tries++;
304 if (tries >= rc->rc_retries)
305 return (stat);
306 continue;
307 }
308 if (stat != RPC_SUCCESS)
309 return (stat);
310 mtx_lock(&rc->rc_lock);
311 }
312
313 if (!rc->rc_client) {
314 mtx_unlock(&rc->rc_lock);
315 stat = RPC_FAILED;
316 continue;
317 }
318 CLNT_ACQUIRE(rc->rc_client);
319 client = rc->rc_client;
320 mtx_unlock(&rc->rc_lock);
321 stat = CLNT_CALL_MBUF(client, ext, proc, args,
322 resultsp, utimeout);
323
324 if (stat != RPC_SUCCESS) {
325 if (!ext)
326 CLNT_GETERR(client, &rc->rc_err);
327 }
328
329 if (stat == RPC_TIMEDOUT) {
330 /*
331 * Check for async send misfeature for NLM
332 * protocol.
333 */
334 if ((rc->rc_timeout.tv_sec == 0
335 && rc->rc_timeout.tv_usec == 0)
336 || (rc->rc_timeout.tv_sec == -1
337 && utimeout.tv_sec == 0
338 && utimeout.tv_usec == 0)) {
339 CLNT_RELEASE(client);
340 break;
341 }
342 }
343
344 if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND
345 || stat == RPC_CANTRECV) {
346 tries++;
347 if (tries >= rc->rc_retries) {
348 CLNT_RELEASE(client);
349 break;
350 }
351
352 if (ext && ext->rc_feedback)
353 ext->rc_feedback(FEEDBACK_RECONNECT, proc,
354 ext->rc_feedback_arg);
355
356 mtx_lock(&rc->rc_lock);
357 /*
358 * Make sure that someone else hasn't already
359 * reconnected by checking if rc_client has changed.
360 * If not, we are done with the client and must
361 * do CLNT_RELEASE(client) twice to dispose of it,
362 * because there is both an initial refcnt and one
363 * acquired by CLNT_ACQUIRE() above.
364 */
365 if (rc->rc_client == client) {
366 rc->rc_client = NULL;
367 mtx_unlock(&rc->rc_lock);
368 CLNT_RELEASE(client);
369 } else {
370 mtx_unlock(&rc->rc_lock);
371 }
372 CLNT_RELEASE(client);
373 } else {
374 CLNT_RELEASE(client);
375 break;
376 }
377 } while (stat != RPC_SUCCESS);
378
379 KASSERT(stat != RPC_SUCCESS || *resultsp,
380 ("RPC_SUCCESS without reply"));
381
382 return (stat);
383 }
384
385 static void
clnt_reconnect_geterr(CLIENT * cl,struct rpc_err * errp)386 clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp)
387 {
388 struct rc_data *rc = (struct rc_data *)cl->cl_private;
389
390 *errp = rc->rc_err;
391 }
392
393 /*
394 * Since this function requires that rc_client be valid, it can
395 * only be called when that is guaranteed to be the case.
396 */
397 static bool_t
clnt_reconnect_freeres(CLIENT * cl,xdrproc_t xdr_res,void * res_ptr)398 clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr)
399 {
400 struct rc_data *rc = (struct rc_data *)cl->cl_private;
401
402 return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr));
403 }
404
405 /*ARGSUSED*/
406 static void
clnt_reconnect_abort(CLIENT * h)407 clnt_reconnect_abort(CLIENT *h)
408 {
409 }
410
411 /*
412 * CLNT_CONTROL() on the client returned by clnt_reconnect_create() must
413 * always be called before CLNT_CALL_MBUF() by a single thread only.
414 */
415 static bool_t
clnt_reconnect_control(CLIENT * cl,u_int request,void * info)416 clnt_reconnect_control(CLIENT *cl, u_int request, void *info)
417 {
418 struct rc_data *rc = (struct rc_data *)cl->cl_private;
419 SVCXPRT *xprt;
420 size_t slen;
421 struct rpc_reconupcall *upcp;
422
423 if (info == NULL) {
424 return (FALSE);
425 }
426 switch (request) {
427 case CLSET_TIMEOUT:
428 rc->rc_timeout = *(struct timeval *)info;
429 if (rc->rc_client)
430 CLNT_CONTROL(rc->rc_client, request, info);
431 break;
432
433 case CLGET_TIMEOUT:
434 *(struct timeval *)info = rc->rc_timeout;
435 break;
436
437 case CLSET_RETRY_TIMEOUT:
438 rc->rc_retry = *(struct timeval *)info;
439 if (rc->rc_client)
440 CLNT_CONTROL(rc->rc_client, request, info);
441 break;
442
443 case CLGET_RETRY_TIMEOUT:
444 *(struct timeval *)info = rc->rc_retry;
445 break;
446
447 case CLGET_VERS:
448 *(uint32_t *)info = rc->rc_vers;
449 break;
450
451 case CLSET_VERS:
452 rc->rc_vers = *(uint32_t *) info;
453 if (rc->rc_client)
454 CLNT_CONTROL(rc->rc_client, CLSET_VERS, info);
455 break;
456
457 case CLGET_PROG:
458 *(uint32_t *)info = rc->rc_prog;
459 break;
460
461 case CLSET_PROG:
462 rc->rc_prog = *(uint32_t *) info;
463 if (rc->rc_client)
464 CLNT_CONTROL(rc->rc_client, request, info);
465 break;
466
467 case CLSET_WAITCHAN:
468 rc->rc_waitchan = (char *)info;
469 if (rc->rc_client)
470 CLNT_CONTROL(rc->rc_client, request, info);
471 break;
472
473 case CLGET_WAITCHAN:
474 *(const char **) info = rc->rc_waitchan;
475 break;
476
477 case CLSET_INTERRUPTIBLE:
478 rc->rc_intr = *(int *) info;
479 if (rc->rc_client)
480 CLNT_CONTROL(rc->rc_client, request, info);
481 break;
482
483 case CLGET_INTERRUPTIBLE:
484 *(int *) info = rc->rc_intr;
485 break;
486
487 case CLSET_RETRIES:
488 rc->rc_retries = *(int *) info;
489 break;
490
491 case CLGET_RETRIES:
492 *(int *) info = rc->rc_retries;
493 break;
494
495 case CLSET_PRIVPORT:
496 rc->rc_privport = *(int *) info;
497 break;
498
499 case CLGET_PRIVPORT:
500 *(int *) info = rc->rc_privport;
501 break;
502
503 case CLSET_BACKCHANNEL:
504 xprt = (SVCXPRT *)info;
505 xprt_register(xprt);
506 rc->rc_backchannel = info;
507 break;
508
509 case CLSET_TLS:
510 rc->rc_tls = true;
511 break;
512
513 case CLSET_TLSCERTNAME:
514 slen = strlen(info) + 1;
515 /*
516 * tlscertname with "key.pem" appended to it forms a file
517 * name. As such, the maximum allowable strlen(info) is
518 * NAME_MAX - 7. However, "slen" includes the nul termination
519 * byte so it can be up to NAME_MAX - 6.
520 */
521 if (slen <= 1 || slen > NAME_MAX - 6)
522 return (FALSE);
523 rc->rc_tlscertname = mem_alloc(slen);
524 strlcpy(rc->rc_tlscertname, info, slen);
525 break;
526
527 case CLSET_RECONUPCALL:
528 upcp = (struct rpc_reconupcall *)info;
529 rc->rc_reconcall = upcp->call;
530 rc->rc_reconarg = upcp->arg;
531 break;
532
533 default:
534 return (FALSE);
535 }
536
537 return (TRUE);
538 }
539
540 static void
clnt_reconnect_close(CLIENT * cl)541 clnt_reconnect_close(CLIENT *cl)
542 {
543 struct rc_data *rc = (struct rc_data *)cl->cl_private;
544 CLIENT *client;
545
546 mtx_lock(&rc->rc_lock);
547
548 if (rc->rc_closed) {
549 mtx_unlock(&rc->rc_lock);
550 return;
551 }
552
553 rc->rc_closed = TRUE;
554 client = rc->rc_client;
555 rc->rc_client = NULL;
556
557 mtx_unlock(&rc->rc_lock);
558
559 if (client) {
560 CLNT_CLOSE(client);
561 CLNT_RELEASE(client);
562 }
563 }
564
565 static void
clnt_reconnect_destroy(CLIENT * cl)566 clnt_reconnect_destroy(CLIENT *cl)
567 {
568 struct rc_data *rc = (struct rc_data *)cl->cl_private;
569 SVCXPRT *xprt;
570
571 if (rc->rc_client)
572 CLNT_DESTROY(rc->rc_client);
573 if (rc->rc_backchannel) {
574 xprt = (SVCXPRT *)rc->rc_backchannel;
575 KASSERT(xprt->xp_socket == NULL,
576 ("clnt_reconnect_destroy: xp_socket not NULL"));
577 xprt_unregister(xprt);
578 SVC_RELEASE(xprt);
579 }
580 crfree(rc->rc_ucred);
581 mtx_destroy(&rc->rc_lock);
582 mem_free(rc->rc_tlscertname, 0); /* 0 ok, since arg. ignored. */
583 mem_free(rc->rc_reconarg, 0);
584 mem_free(rc, sizeof(*rc));
585 mem_free(cl, sizeof (CLIENT));
586 }
587