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