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 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; 114 115 cl->cl_refs = 1; 116 cl->cl_ops = &clnt_reconnect_ops; 117 cl->cl_private = (caddr_t)(void *)rc; 118 cl->cl_auth = authnone_create(); 119 cl->cl_tp = NULL; 120 cl->cl_netid = NULL; 121 return (cl); 122 } 123 124 static enum clnt_stat 125 clnt_reconnect_connect(CLIENT *cl) 126 { 127 struct thread *td = curthread; 128 struct rc_data *rc = (struct rc_data *)cl->cl_private; 129 struct socket *so; 130 enum clnt_stat stat; 131 int error; 132 int one = 1; 133 struct ucred *oldcred; 134 CLIENT *newclient = NULL; 135 uint64_t ssl[3]; 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 if (rc->rc_tls && newclient != NULL) { 202 stat = rpctls_connect(newclient, rc->rc_tlscertname, so, 203 ssl, &reterr); 204 if (stat != RPC_SUCCESS || reterr != RPCTLSERR_OK) { 205 if (stat == RPC_SUCCESS) 206 stat = RPC_FAILED; 207 stat = rpc_createerr.cf_stat = stat; 208 rpc_createerr.cf_error.re_errno = 0; 209 CLNT_CLOSE(newclient); 210 CLNT_RELEASE(newclient); 211 newclient = NULL; 212 td->td_ucred = oldcred; 213 goto out; 214 } 215 } 216 } 217 td->td_ucred = oldcred; 218 219 if (!newclient) { 220 soclose(so); 221 rc->rc_err = rpc_createerr.cf_error; 222 stat = rpc_createerr.cf_stat; 223 goto out; 224 } 225 226 CLNT_CONTROL(newclient, CLSET_FD_CLOSE, 0); 227 CLNT_CONTROL(newclient, CLSET_CONNECT, &one); 228 CLNT_CONTROL(newclient, CLSET_TIMEOUT, &rc->rc_timeout); 229 CLNT_CONTROL(newclient, CLSET_RETRY_TIMEOUT, &rc->rc_retry); 230 CLNT_CONTROL(newclient, CLSET_WAITCHAN, rc->rc_waitchan); 231 CLNT_CONTROL(newclient, CLSET_INTERRUPTIBLE, &rc->rc_intr); 232 if (rc->rc_tls) 233 CLNT_CONTROL(newclient, CLSET_TLS, ssl); 234 if (rc->rc_backchannel != NULL) 235 CLNT_CONTROL(newclient, CLSET_BACKCHANNEL, rc->rc_backchannel); 236 stat = RPC_SUCCESS; 237 238 out: 239 mtx_lock(&rc->rc_lock); 240 KASSERT(rc->rc_client == NULL, ("rc_client not null")); 241 if (!rc->rc_closed) { 242 rc->rc_client = newclient; 243 newclient = NULL; 244 } 245 rc->rc_connecting = FALSE; 246 wakeup(rc); 247 mtx_unlock(&rc->rc_lock); 248 249 if (newclient) { 250 /* 251 * It has been closed, so discard the new client. 252 * nb: clnt_[dg|vc]_close()/clnt_[dg|vc]_destroy() cannot 253 * be called with the rc_lock mutex held, since they may 254 * msleep() while holding a different mutex. 255 */ 256 CLNT_CLOSE(newclient); 257 CLNT_RELEASE(newclient); 258 } 259 260 return (stat); 261 } 262 263 static enum clnt_stat 264 clnt_reconnect_call( 265 CLIENT *cl, /* client handle */ 266 struct rpc_callextra *ext, /* call metadata */ 267 rpcproc_t proc, /* procedure number */ 268 struct mbuf *args, /* pointer to args */ 269 struct mbuf **resultsp, /* pointer to results */ 270 struct timeval utimeout) 271 { 272 struct rc_data *rc = (struct rc_data *)cl->cl_private; 273 CLIENT *client; 274 enum clnt_stat stat; 275 int tries, error; 276 277 tries = 0; 278 do { 279 mtx_lock(&rc->rc_lock); 280 if (rc->rc_closed) { 281 mtx_unlock(&rc->rc_lock); 282 return (RPC_CANTSEND); 283 } 284 285 if (!rc->rc_client) { 286 mtx_unlock(&rc->rc_lock); 287 stat = clnt_reconnect_connect(cl); 288 if (stat == RPC_SYSTEMERROR) { 289 error = tsleep(&fake_wchan, 290 rc->rc_intr ? PCATCH : 0, "rpccon", hz); 291 if (error == EINTR || error == ERESTART) 292 return (RPC_INTR); 293 tries++; 294 if (tries >= rc->rc_retries) 295 return (stat); 296 continue; 297 } 298 if (stat != RPC_SUCCESS) 299 return (stat); 300 mtx_lock(&rc->rc_lock); 301 } 302 303 if (!rc->rc_client) { 304 mtx_unlock(&rc->rc_lock); 305 stat = RPC_FAILED; 306 continue; 307 } 308 CLNT_ACQUIRE(rc->rc_client); 309 client = rc->rc_client; 310 mtx_unlock(&rc->rc_lock); 311 stat = CLNT_CALL_MBUF(client, ext, proc, args, 312 resultsp, utimeout); 313 314 if (stat != RPC_SUCCESS) { 315 if (!ext) 316 CLNT_GETERR(client, &rc->rc_err); 317 } 318 319 if (stat == RPC_TIMEDOUT) { 320 /* 321 * Check for async send misfeature for NLM 322 * protocol. 323 */ 324 if ((rc->rc_timeout.tv_sec == 0 325 && rc->rc_timeout.tv_usec == 0) 326 || (rc->rc_timeout.tv_sec == -1 327 && utimeout.tv_sec == 0 328 && utimeout.tv_usec == 0)) { 329 CLNT_RELEASE(client); 330 break; 331 } 332 } 333 334 if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND 335 || stat == RPC_CANTRECV) { 336 tries++; 337 if (tries >= rc->rc_retries) { 338 CLNT_RELEASE(client); 339 break; 340 } 341 342 if (ext && ext->rc_feedback) 343 ext->rc_feedback(FEEDBACK_RECONNECT, proc, 344 ext->rc_feedback_arg); 345 346 mtx_lock(&rc->rc_lock); 347 /* 348 * Make sure that someone else hasn't already 349 * reconnected by checking if rc_client has changed. 350 * If not, we are done with the client and must 351 * do CLNT_RELEASE(client) twice to dispose of it, 352 * because there is both an initial refcnt and one 353 * acquired by CLNT_ACQUIRE() above. 354 */ 355 if (rc->rc_client == client) { 356 rc->rc_client = NULL; 357 mtx_unlock(&rc->rc_lock); 358 CLNT_RELEASE(client); 359 } else { 360 mtx_unlock(&rc->rc_lock); 361 } 362 CLNT_RELEASE(client); 363 } else { 364 CLNT_RELEASE(client); 365 break; 366 } 367 } while (stat != RPC_SUCCESS); 368 369 KASSERT(stat != RPC_SUCCESS || *resultsp, 370 ("RPC_SUCCESS without reply")); 371 372 return (stat); 373 } 374 375 static void 376 clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp) 377 { 378 struct rc_data *rc = (struct rc_data *)cl->cl_private; 379 380 *errp = rc->rc_err; 381 } 382 383 /* 384 * Since this function requires that rc_client be valid, it can 385 * only be called when that is guaranteed to be the case. 386 */ 387 static bool_t 388 clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr) 389 { 390 struct rc_data *rc = (struct rc_data *)cl->cl_private; 391 392 return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr)); 393 } 394 395 /*ARGSUSED*/ 396 static void 397 clnt_reconnect_abort(CLIENT *h) 398 { 399 } 400 401 /* 402 * CLNT_CONTROL() on the client returned by clnt_reconnect_create() must 403 * always be called before CLNT_CALL_MBUF() by a single thread only. 404 */ 405 static bool_t 406 clnt_reconnect_control(CLIENT *cl, u_int request, void *info) 407 { 408 struct rc_data *rc = (struct rc_data *)cl->cl_private; 409 SVCXPRT *xprt; 410 size_t slen; 411 412 if (info == NULL) { 413 return (FALSE); 414 } 415 switch (request) { 416 case CLSET_TIMEOUT: 417 rc->rc_timeout = *(struct timeval *)info; 418 if (rc->rc_client) 419 CLNT_CONTROL(rc->rc_client, request, info); 420 break; 421 422 case CLGET_TIMEOUT: 423 *(struct timeval *)info = rc->rc_timeout; 424 break; 425 426 case CLSET_RETRY_TIMEOUT: 427 rc->rc_retry = *(struct timeval *)info; 428 if (rc->rc_client) 429 CLNT_CONTROL(rc->rc_client, request, info); 430 break; 431 432 case CLGET_RETRY_TIMEOUT: 433 *(struct timeval *)info = rc->rc_retry; 434 break; 435 436 case CLGET_VERS: 437 *(uint32_t *)info = rc->rc_vers; 438 break; 439 440 case CLSET_VERS: 441 rc->rc_vers = *(uint32_t *) info; 442 if (rc->rc_client) 443 CLNT_CONTROL(rc->rc_client, CLSET_VERS, info); 444 break; 445 446 case CLGET_PROG: 447 *(uint32_t *)info = rc->rc_prog; 448 break; 449 450 case CLSET_PROG: 451 rc->rc_prog = *(uint32_t *) info; 452 if (rc->rc_client) 453 CLNT_CONTROL(rc->rc_client, request, info); 454 break; 455 456 case CLSET_WAITCHAN: 457 rc->rc_waitchan = (char *)info; 458 if (rc->rc_client) 459 CLNT_CONTROL(rc->rc_client, request, info); 460 break; 461 462 case CLGET_WAITCHAN: 463 *(const char **) info = rc->rc_waitchan; 464 break; 465 466 case CLSET_INTERRUPTIBLE: 467 rc->rc_intr = *(int *) info; 468 if (rc->rc_client) 469 CLNT_CONTROL(rc->rc_client, request, info); 470 break; 471 472 case CLGET_INTERRUPTIBLE: 473 *(int *) info = rc->rc_intr; 474 break; 475 476 case CLSET_RETRIES: 477 rc->rc_retries = *(int *) info; 478 break; 479 480 case CLGET_RETRIES: 481 *(int *) info = rc->rc_retries; 482 break; 483 484 case CLSET_PRIVPORT: 485 rc->rc_privport = *(int *) info; 486 break; 487 488 case CLGET_PRIVPORT: 489 *(int *) info = rc->rc_privport; 490 break; 491 492 case CLSET_BACKCHANNEL: 493 xprt = (SVCXPRT *)info; 494 xprt_register(xprt); 495 rc->rc_backchannel = info; 496 break; 497 498 case CLSET_TLS: 499 rc->rc_tls = true; 500 break; 501 502 case CLSET_TLSCERTNAME: 503 slen = strlen(info) + 1; 504 /* 505 * tlscertname with "key.pem" appended to it forms a file 506 * name. As such, the maximum allowable strlen(info) is 507 * NAME_MAX - 7. However, "slen" includes the nul termination 508 * byte so it can be up to NAME_MAX - 6. 509 */ 510 if (slen <= 1 || slen > NAME_MAX - 6) 511 return (FALSE); 512 rc->rc_tlscertname = mem_alloc(slen); 513 strlcpy(rc->rc_tlscertname, info, slen); 514 break; 515 516 default: 517 return (FALSE); 518 } 519 520 return (TRUE); 521 } 522 523 static void 524 clnt_reconnect_close(CLIENT *cl) 525 { 526 struct rc_data *rc = (struct rc_data *)cl->cl_private; 527 CLIENT *client; 528 529 mtx_lock(&rc->rc_lock); 530 531 if (rc->rc_closed) { 532 mtx_unlock(&rc->rc_lock); 533 return; 534 } 535 536 rc->rc_closed = TRUE; 537 client = rc->rc_client; 538 rc->rc_client = NULL; 539 540 mtx_unlock(&rc->rc_lock); 541 542 if (client) { 543 CLNT_CLOSE(client); 544 CLNT_RELEASE(client); 545 } 546 } 547 548 static void 549 clnt_reconnect_destroy(CLIENT *cl) 550 { 551 struct rc_data *rc = (struct rc_data *)cl->cl_private; 552 SVCXPRT *xprt; 553 554 if (rc->rc_client) 555 CLNT_DESTROY(rc->rc_client); 556 if (rc->rc_backchannel) { 557 xprt = (SVCXPRT *)rc->rc_backchannel; 558 xprt_unregister(xprt); 559 SVC_RELEASE(xprt); 560 } 561 crfree(rc->rc_ucred); 562 mtx_destroy(&rc->rc_lock); 563 mem_free(rc->rc_tlscertname, 0); /* 0 ok, since arg. ignored. */ 564 mem_free(rc, sizeof(*rc)); 565 mem_free(cl, sizeof (CLIENT)); 566 } 567