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