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 * 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 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 uint32_t reterr; 137 138 mtx_lock(&rc->rc_lock); 139 while (rc->rc_connecting) { 140 error = msleep(rc, &rc->rc_lock, 141 rc->rc_intr ? PCATCH : 0, "rpcrecon", 0); 142 if (error) { 143 mtx_unlock(&rc->rc_lock); 144 return (RPC_INTR); 145 } 146 } 147 if (rc->rc_closed) { 148 mtx_unlock(&rc->rc_lock); 149 return (RPC_CANTSEND); 150 } 151 if (rc->rc_client) { 152 mtx_unlock(&rc->rc_lock); 153 return (RPC_SUCCESS); 154 } 155 156 /* 157 * My turn to attempt a connect. The rc_connecting variable 158 * serializes the following code sequence, so it is guaranteed 159 * that rc_client will still be NULL after it is re-locked below, 160 * since that is the only place it is set non-NULL. 161 */ 162 rc->rc_connecting = TRUE; 163 mtx_unlock(&rc->rc_lock); 164 165 oldcred = td->td_ucred; 166 td->td_ucred = rc->rc_ucred; 167 so = __rpc_nconf2socket(rc->rc_nconf); 168 if (!so) { 169 stat = rpc_createerr.cf_stat = RPC_TLIERROR; 170 rpc_createerr.cf_error.re_errno = 0; 171 td->td_ucred = oldcred; 172 goto out; 173 } 174 175 if (rc->rc_privport) 176 bindresvport(so, NULL); 177 178 if (rc->rc_nconf->nc_semantics == NC_TPI_CLTS) 179 newclient = clnt_dg_create(so, 180 (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers, 181 rc->rc_sendsz, rc->rc_recvsz); 182 else { 183 /* 184 * I do not believe a timeout of less than 1sec would make 185 * sense here since short delays can occur when a server is 186 * temporarily overloaded. 187 */ 188 if (rc->rc_timeout.tv_sec > 0 && rc->rc_timeout.tv_usec >= 0) { 189 error = so_setsockopt(so, SOL_SOCKET, SO_SNDTIMEO, 190 &rc->rc_timeout, sizeof(struct timeval)); 191 if (error != 0) { 192 stat = rpc_createerr.cf_stat = RPC_CANTSEND; 193 rpc_createerr.cf_error.re_errno = error; 194 td->td_ucred = oldcred; 195 goto out; 196 } 197 } 198 newclient = clnt_vc_create(so, 199 (struct sockaddr *) &rc->rc_addr, rc->rc_prog, rc->rc_vers, 200 rc->rc_sendsz, rc->rc_recvsz, rc->rc_intr); 201 /* 202 * CLSET_FD_CLOSE must be done now, in case rpctls_connect() 203 * fails just below. 204 */ 205 if (newclient != NULL) 206 CLNT_CONTROL(newclient, CLSET_FD_CLOSE, 0); 207 if (rc->rc_tls && newclient != NULL) { 208 CURVNET_SET(so->so_vnet); 209 stat = rpctls_connect(newclient, rc->rc_tlscertname, so, 210 &reterr); 211 CURVNET_RESTORE(); 212 if (stat != RPC_SUCCESS || reterr != RPCTLSERR_OK) { 213 if (stat == RPC_SUCCESS) 214 stat = RPC_FAILED; 215 stat = rpc_createerr.cf_stat = stat; 216 rpc_createerr.cf_error.re_errno = 0; 217 CLNT_CLOSE(newclient); 218 CLNT_RELEASE(newclient); 219 newclient = NULL; 220 td->td_ucred = oldcred; 221 goto out; 222 } 223 CLNT_CONTROL(newclient, CLSET_TLS, 224 &(int){RPCTLS_COMPLETE}); 225 } 226 if (newclient != NULL) { 227 int optval = 1; 228 229 (void)so_setsockopt(so, IPPROTO_TCP, TCP_USE_DDP, 230 &optval, sizeof(optval)); 231 } 232 if (newclient != NULL && rc->rc_reconcall != NULL) 233 (*rc->rc_reconcall)(newclient, rc->rc_reconarg, 234 rc->rc_ucred); 235 } 236 td->td_ucred = oldcred; 237 238 if (!newclient) { 239 soclose(so); 240 rc->rc_err = rpc_createerr.cf_error; 241 stat = rpc_createerr.cf_stat; 242 goto out; 243 } 244 245 CLNT_CONTROL(newclient, CLSET_CONNECT, &one); 246 CLNT_CONTROL(newclient, CLSET_TIMEOUT, &rc->rc_timeout); 247 CLNT_CONTROL(newclient, CLSET_RETRY_TIMEOUT, &rc->rc_retry); 248 CLNT_CONTROL(newclient, CLSET_WAITCHAN, rc->rc_waitchan); 249 CLNT_CONTROL(newclient, CLSET_INTERRUPTIBLE, &rc->rc_intr); 250 if (rc->rc_backchannel != NULL) 251 CLNT_CONTROL(newclient, CLSET_BACKCHANNEL, rc->rc_backchannel); 252 stat = RPC_SUCCESS; 253 254 out: 255 mtx_lock(&rc->rc_lock); 256 KASSERT(rc->rc_client == NULL, ("rc_client not null")); 257 if (!rc->rc_closed) { 258 rc->rc_client = newclient; 259 newclient = NULL; 260 } 261 rc->rc_connecting = FALSE; 262 wakeup(rc); 263 mtx_unlock(&rc->rc_lock); 264 265 if (newclient) { 266 /* 267 * It has been closed, so discard the new client. 268 * nb: clnt_[dg|vc]_close()/clnt_[dg|vc]_destroy() cannot 269 * be called with the rc_lock mutex held, since they may 270 * msleep() while holding a different mutex. 271 */ 272 CLNT_CLOSE(newclient); 273 CLNT_RELEASE(newclient); 274 } 275 276 return (stat); 277 } 278 279 static enum clnt_stat 280 clnt_reconnect_call( 281 CLIENT *cl, /* client handle */ 282 struct rpc_callextra *ext, /* call metadata */ 283 rpcproc_t proc, /* procedure number */ 284 struct mbuf *args, /* pointer to args */ 285 struct mbuf **resultsp, /* pointer to results */ 286 struct timeval utimeout) 287 { 288 struct rc_data *rc = (struct rc_data *)cl->cl_private; 289 CLIENT *client; 290 enum clnt_stat stat; 291 int tries, error; 292 293 tries = 0; 294 do { 295 mtx_lock(&rc->rc_lock); 296 if (rc->rc_closed) { 297 mtx_unlock(&rc->rc_lock); 298 return (RPC_CANTSEND); 299 } 300 301 if (!rc->rc_client) { 302 mtx_unlock(&rc->rc_lock); 303 stat = clnt_reconnect_connect(cl); 304 if (stat == RPC_SYSTEMERROR) { 305 error = tsleep(&fake_wchan, 306 rc->rc_intr ? PCATCH : 0, "rpccon", hz); 307 if (error == EINTR || error == ERESTART) 308 return (RPC_INTR); 309 tries++; 310 if (tries >= rc->rc_retries) 311 return (stat); 312 continue; 313 } 314 if (stat != RPC_SUCCESS) 315 return (stat); 316 mtx_lock(&rc->rc_lock); 317 } 318 319 if (!rc->rc_client) { 320 mtx_unlock(&rc->rc_lock); 321 stat = RPC_FAILED; 322 continue; 323 } 324 CLNT_ACQUIRE(rc->rc_client); 325 client = rc->rc_client; 326 mtx_unlock(&rc->rc_lock); 327 stat = CLNT_CALL_MBUF(client, ext, proc, args, 328 resultsp, utimeout); 329 330 if (stat != RPC_SUCCESS) { 331 if (!ext) 332 CLNT_GETERR(client, &rc->rc_err); 333 } 334 335 if (stat == RPC_TIMEDOUT) { 336 /* 337 * Check for async send misfeature for NLM 338 * protocol. 339 */ 340 if ((rc->rc_timeout.tv_sec == 0 341 && rc->rc_timeout.tv_usec == 0) 342 || (rc->rc_timeout.tv_sec == -1 343 && utimeout.tv_sec == 0 344 && utimeout.tv_usec == 0)) { 345 CLNT_RELEASE(client); 346 break; 347 } 348 } 349 350 if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND 351 || stat == RPC_CANTRECV) { 352 tries++; 353 if (tries >= rc->rc_retries) { 354 CLNT_RELEASE(client); 355 break; 356 } 357 358 if (ext && ext->rc_feedback) 359 ext->rc_feedback(FEEDBACK_RECONNECT, proc, 360 ext->rc_feedback_arg); 361 362 mtx_lock(&rc->rc_lock); 363 /* 364 * Make sure that someone else hasn't already 365 * reconnected by checking if rc_client has changed. 366 * If not, we are done with the client and must 367 * do CLNT_RELEASE(client) twice to dispose of it, 368 * because there is both an initial refcnt and one 369 * acquired by CLNT_ACQUIRE() above. 370 */ 371 if (rc->rc_client == client) { 372 rc->rc_client = NULL; 373 mtx_unlock(&rc->rc_lock); 374 CLNT_RELEASE(client); 375 } else { 376 mtx_unlock(&rc->rc_lock); 377 } 378 CLNT_RELEASE(client); 379 } else { 380 CLNT_RELEASE(client); 381 break; 382 } 383 } while (stat != RPC_SUCCESS); 384 385 KASSERT(stat != RPC_SUCCESS || *resultsp, 386 ("RPC_SUCCESS without reply")); 387 388 return (stat); 389 } 390 391 static void 392 clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp) 393 { 394 struct rc_data *rc = (struct rc_data *)cl->cl_private; 395 396 *errp = rc->rc_err; 397 } 398 399 /* 400 * Since this function requires that rc_client be valid, it can 401 * only be called when that is guaranteed to be the case. 402 */ 403 static bool_t 404 clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr) 405 { 406 struct rc_data *rc = (struct rc_data *)cl->cl_private; 407 408 return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr)); 409 } 410 411 /*ARGSUSED*/ 412 static void 413 clnt_reconnect_abort(CLIENT *h) 414 { 415 } 416 417 /* 418 * CLNT_CONTROL() on the client returned by clnt_reconnect_create() must 419 * always be called before CLNT_CALL_MBUF() by a single thread only. 420 */ 421 static bool_t 422 clnt_reconnect_control(CLIENT *cl, u_int request, void *info) 423 { 424 struct rc_data *rc = (struct rc_data *)cl->cl_private; 425 SVCXPRT *xprt; 426 size_t slen; 427 struct rpc_reconupcall *upcp; 428 429 if (info == NULL) { 430 return (FALSE); 431 } 432 switch (request) { 433 case CLSET_TIMEOUT: 434 rc->rc_timeout = *(struct timeval *)info; 435 if (rc->rc_client) 436 CLNT_CONTROL(rc->rc_client, request, info); 437 break; 438 439 case CLGET_TIMEOUT: 440 *(struct timeval *)info = rc->rc_timeout; 441 break; 442 443 case CLSET_RETRY_TIMEOUT: 444 rc->rc_retry = *(struct timeval *)info; 445 if (rc->rc_client) 446 CLNT_CONTROL(rc->rc_client, request, info); 447 break; 448 449 case CLGET_RETRY_TIMEOUT: 450 *(struct timeval *)info = rc->rc_retry; 451 break; 452 453 case CLGET_VERS: 454 *(uint32_t *)info = rc->rc_vers; 455 break; 456 457 case CLSET_VERS: 458 rc->rc_vers = *(uint32_t *) info; 459 if (rc->rc_client) 460 CLNT_CONTROL(rc->rc_client, CLSET_VERS, info); 461 break; 462 463 case CLGET_PROG: 464 *(uint32_t *)info = rc->rc_prog; 465 break; 466 467 case CLSET_PROG: 468 rc->rc_prog = *(uint32_t *) info; 469 if (rc->rc_client) 470 CLNT_CONTROL(rc->rc_client, request, info); 471 break; 472 473 case CLSET_WAITCHAN: 474 rc->rc_waitchan = (char *)info; 475 if (rc->rc_client) 476 CLNT_CONTROL(rc->rc_client, request, info); 477 break; 478 479 case CLGET_WAITCHAN: 480 *(const char **) info = rc->rc_waitchan; 481 break; 482 483 case CLSET_INTERRUPTIBLE: 484 rc->rc_intr = *(int *) info; 485 if (rc->rc_client) 486 CLNT_CONTROL(rc->rc_client, request, info); 487 break; 488 489 case CLGET_INTERRUPTIBLE: 490 *(int *) info = rc->rc_intr; 491 break; 492 493 case CLSET_RETRIES: 494 rc->rc_retries = *(int *) info; 495 break; 496 497 case CLGET_RETRIES: 498 *(int *) info = rc->rc_retries; 499 break; 500 501 case CLSET_PRIVPORT: 502 rc->rc_privport = *(int *) info; 503 break; 504 505 case CLGET_PRIVPORT: 506 *(int *) info = rc->rc_privport; 507 break; 508 509 case CLSET_BACKCHANNEL: 510 xprt = (SVCXPRT *)info; 511 xprt_register(xprt); 512 rc->rc_backchannel = info; 513 break; 514 515 case CLSET_TLS: 516 rc->rc_tls = true; 517 break; 518 519 case CLSET_TLSCERTNAME: 520 slen = strlen(info) + 1; 521 /* 522 * tlscertname with "key.pem" appended to it forms a file 523 * name. As such, the maximum allowable strlen(info) is 524 * NAME_MAX - 7. However, "slen" includes the nul termination 525 * byte so it can be up to NAME_MAX - 6. 526 */ 527 if (slen <= 1 || slen > NAME_MAX - 6) 528 return (FALSE); 529 rc->rc_tlscertname = mem_alloc(slen); 530 strlcpy(rc->rc_tlscertname, info, slen); 531 break; 532 533 case CLSET_RECONUPCALL: 534 upcp = (struct rpc_reconupcall *)info; 535 rc->rc_reconcall = upcp->call; 536 rc->rc_reconarg = upcp->arg; 537 break; 538 539 default: 540 return (FALSE); 541 } 542 543 return (TRUE); 544 } 545 546 static void 547 clnt_reconnect_close(CLIENT *cl) 548 { 549 struct rc_data *rc = (struct rc_data *)cl->cl_private; 550 CLIENT *client; 551 552 mtx_lock(&rc->rc_lock); 553 554 if (rc->rc_closed) { 555 mtx_unlock(&rc->rc_lock); 556 return; 557 } 558 559 rc->rc_closed = TRUE; 560 client = rc->rc_client; 561 rc->rc_client = NULL; 562 563 mtx_unlock(&rc->rc_lock); 564 565 if (client) { 566 CLNT_CLOSE(client); 567 CLNT_RELEASE(client); 568 } 569 } 570 571 static void 572 clnt_reconnect_destroy(CLIENT *cl) 573 { 574 struct rc_data *rc = (struct rc_data *)cl->cl_private; 575 SVCXPRT *xprt; 576 577 if (rc->rc_client) 578 CLNT_DESTROY(rc->rc_client); 579 if (rc->rc_backchannel) { 580 xprt = (SVCXPRT *)rc->rc_backchannel; 581 KASSERT(xprt->xp_socket == NULL, 582 ("clnt_reconnect_destroy: xp_socket not NULL")); 583 xprt_unregister(xprt); 584 SVC_RELEASE(xprt); 585 } 586 crfree(rc->rc_ucred); 587 mtx_destroy(&rc->rc_lock); 588 mem_free(rc->rc_tlscertname, 0); /* 0 ok, since arg. ignored. */ 589 mem_free(rc->rc_reconarg, 0); 590 mem_free(rc, sizeof(*rc)); 591 mem_free(cl, sizeof (CLIENT)); 592 } 593