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; 113 114 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, so, ssl, &reterr); 202 if (stat != RPC_SUCCESS || reterr != RPCTLSERR_OK) { 203 if (stat == RPC_SUCCESS) 204 stat = RPC_FAILED; 205 stat = rpc_createerr.cf_stat = stat; 206 rpc_createerr.cf_error.re_errno = 0; 207 CLNT_CLOSE(newclient); 208 CLNT_RELEASE(newclient); 209 newclient = NULL; 210 td->td_ucred = oldcred; 211 goto out; 212 } 213 } 214 } 215 td->td_ucred = oldcred; 216 217 if (!newclient) { 218 soclose(so); 219 rc->rc_err = rpc_createerr.cf_error; 220 stat = rpc_createerr.cf_stat; 221 goto out; 222 } 223 224 CLNT_CONTROL(newclient, CLSET_FD_CLOSE, 0); 225 CLNT_CONTROL(newclient, CLSET_CONNECT, &one); 226 CLNT_CONTROL(newclient, CLSET_TIMEOUT, &rc->rc_timeout); 227 CLNT_CONTROL(newclient, CLSET_RETRY_TIMEOUT, &rc->rc_retry); 228 CLNT_CONTROL(newclient, CLSET_WAITCHAN, rc->rc_waitchan); 229 CLNT_CONTROL(newclient, CLSET_INTERRUPTIBLE, &rc->rc_intr); 230 if (rc->rc_tls) 231 CLNT_CONTROL(newclient, CLSET_TLS, ssl); 232 if (rc->rc_backchannel != NULL) 233 CLNT_CONTROL(newclient, CLSET_BACKCHANNEL, rc->rc_backchannel); 234 stat = RPC_SUCCESS; 235 236 out: 237 mtx_lock(&rc->rc_lock); 238 KASSERT(rc->rc_client == NULL, ("rc_client not null")); 239 if (!rc->rc_closed) { 240 rc->rc_client = newclient; 241 newclient = NULL; 242 } 243 rc->rc_connecting = FALSE; 244 wakeup(rc); 245 mtx_unlock(&rc->rc_lock); 246 247 if (newclient) { 248 /* 249 * It has been closed, so discard the new client. 250 * nb: clnt_[dg|vc]_close()/clnt_[dg|vc]_destroy() cannot 251 * be called with the rc_lock mutex held, since they may 252 * msleep() while holding a different mutex. 253 */ 254 CLNT_CLOSE(newclient); 255 CLNT_RELEASE(newclient); 256 } 257 258 return (stat); 259 } 260 261 static enum clnt_stat 262 clnt_reconnect_call( 263 CLIENT *cl, /* client handle */ 264 struct rpc_callextra *ext, /* call metadata */ 265 rpcproc_t proc, /* procedure number */ 266 struct mbuf *args, /* pointer to args */ 267 struct mbuf **resultsp, /* pointer to results */ 268 struct timeval utimeout) 269 { 270 struct rc_data *rc = (struct rc_data *)cl->cl_private; 271 CLIENT *client; 272 enum clnt_stat stat; 273 int tries, error; 274 275 tries = 0; 276 do { 277 mtx_lock(&rc->rc_lock); 278 if (rc->rc_closed) { 279 mtx_unlock(&rc->rc_lock); 280 return (RPC_CANTSEND); 281 } 282 283 if (!rc->rc_client) { 284 mtx_unlock(&rc->rc_lock); 285 stat = clnt_reconnect_connect(cl); 286 if (stat == RPC_SYSTEMERROR) { 287 error = tsleep(&fake_wchan, 288 rc->rc_intr ? PCATCH : 0, "rpccon", hz); 289 if (error == EINTR || error == ERESTART) 290 return (RPC_INTR); 291 tries++; 292 if (tries >= rc->rc_retries) 293 return (stat); 294 continue; 295 } 296 if (stat != RPC_SUCCESS) 297 return (stat); 298 mtx_lock(&rc->rc_lock); 299 } 300 301 if (!rc->rc_client) { 302 mtx_unlock(&rc->rc_lock); 303 stat = RPC_FAILED; 304 continue; 305 } 306 CLNT_ACQUIRE(rc->rc_client); 307 client = rc->rc_client; 308 mtx_unlock(&rc->rc_lock); 309 stat = CLNT_CALL_MBUF(client, ext, proc, args, 310 resultsp, utimeout); 311 312 if (stat != RPC_SUCCESS) { 313 if (!ext) 314 CLNT_GETERR(client, &rc->rc_err); 315 } 316 317 if (stat == RPC_TIMEDOUT) { 318 /* 319 * Check for async send misfeature for NLM 320 * protocol. 321 */ 322 if ((rc->rc_timeout.tv_sec == 0 323 && rc->rc_timeout.tv_usec == 0) 324 || (rc->rc_timeout.tv_sec == -1 325 && utimeout.tv_sec == 0 326 && utimeout.tv_usec == 0)) { 327 CLNT_RELEASE(client); 328 break; 329 } 330 } 331 332 if (stat == RPC_TIMEDOUT || stat == RPC_CANTSEND 333 || stat == RPC_CANTRECV) { 334 tries++; 335 if (tries >= rc->rc_retries) { 336 CLNT_RELEASE(client); 337 break; 338 } 339 340 if (ext && ext->rc_feedback) 341 ext->rc_feedback(FEEDBACK_RECONNECT, proc, 342 ext->rc_feedback_arg); 343 344 mtx_lock(&rc->rc_lock); 345 /* 346 * Make sure that someone else hasn't already 347 * reconnected by checking if rc_client has changed. 348 * If not, we are done with the client and must 349 * do CLNT_RELEASE(client) twice to dispose of it, 350 * because there is both an initial refcnt and one 351 * acquired by CLNT_ACQUIRE() above. 352 */ 353 if (rc->rc_client == client) { 354 rc->rc_client = NULL; 355 mtx_unlock(&rc->rc_lock); 356 CLNT_RELEASE(client); 357 } else { 358 mtx_unlock(&rc->rc_lock); 359 } 360 CLNT_RELEASE(client); 361 } else { 362 CLNT_RELEASE(client); 363 break; 364 } 365 } while (stat != RPC_SUCCESS); 366 367 KASSERT(stat != RPC_SUCCESS || *resultsp, 368 ("RPC_SUCCESS without reply")); 369 370 return (stat); 371 } 372 373 static void 374 clnt_reconnect_geterr(CLIENT *cl, struct rpc_err *errp) 375 { 376 struct rc_data *rc = (struct rc_data *)cl->cl_private; 377 378 *errp = rc->rc_err; 379 } 380 381 /* 382 * Since this function requires that rc_client be valid, it can 383 * only be called when that is guaranteed to be the case. 384 */ 385 static bool_t 386 clnt_reconnect_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr) 387 { 388 struct rc_data *rc = (struct rc_data *)cl->cl_private; 389 390 return (CLNT_FREERES(rc->rc_client, xdr_res, res_ptr)); 391 } 392 393 /*ARGSUSED*/ 394 static void 395 clnt_reconnect_abort(CLIENT *h) 396 { 397 } 398 399 /* 400 * CLNT_CONTROL() on the client returned by clnt_reconnect_create() must 401 * always be called before CLNT_CALL_MBUF() by a single thread only. 402 */ 403 static bool_t 404 clnt_reconnect_control(CLIENT *cl, u_int request, void *info) 405 { 406 struct rc_data *rc = (struct rc_data *)cl->cl_private; 407 SVCXPRT *xprt; 408 409 if (info == NULL) { 410 return (FALSE); 411 } 412 switch (request) { 413 case CLSET_TIMEOUT: 414 rc->rc_timeout = *(struct timeval *)info; 415 if (rc->rc_client) 416 CLNT_CONTROL(rc->rc_client, request, info); 417 break; 418 419 case CLGET_TIMEOUT: 420 *(struct timeval *)info = rc->rc_timeout; 421 break; 422 423 case CLSET_RETRY_TIMEOUT: 424 rc->rc_retry = *(struct timeval *)info; 425 if (rc->rc_client) 426 CLNT_CONTROL(rc->rc_client, request, info); 427 break; 428 429 case CLGET_RETRY_TIMEOUT: 430 *(struct timeval *)info = rc->rc_retry; 431 break; 432 433 case CLGET_VERS: 434 *(uint32_t *)info = rc->rc_vers; 435 break; 436 437 case CLSET_VERS: 438 rc->rc_vers = *(uint32_t *) info; 439 if (rc->rc_client) 440 CLNT_CONTROL(rc->rc_client, CLSET_VERS, info); 441 break; 442 443 case CLGET_PROG: 444 *(uint32_t *)info = rc->rc_prog; 445 break; 446 447 case CLSET_PROG: 448 rc->rc_prog = *(uint32_t *) info; 449 if (rc->rc_client) 450 CLNT_CONTROL(rc->rc_client, request, info); 451 break; 452 453 case CLSET_WAITCHAN: 454 rc->rc_waitchan = (char *)info; 455 if (rc->rc_client) 456 CLNT_CONTROL(rc->rc_client, request, info); 457 break; 458 459 case CLGET_WAITCHAN: 460 *(const char **) info = rc->rc_waitchan; 461 break; 462 463 case CLSET_INTERRUPTIBLE: 464 rc->rc_intr = *(int *) info; 465 if (rc->rc_client) 466 CLNT_CONTROL(rc->rc_client, request, info); 467 break; 468 469 case CLGET_INTERRUPTIBLE: 470 *(int *) info = rc->rc_intr; 471 break; 472 473 case CLSET_RETRIES: 474 rc->rc_retries = *(int *) info; 475 break; 476 477 case CLGET_RETRIES: 478 *(int *) info = rc->rc_retries; 479 break; 480 481 case CLSET_PRIVPORT: 482 rc->rc_privport = *(int *) info; 483 break; 484 485 case CLGET_PRIVPORT: 486 *(int *) info = rc->rc_privport; 487 break; 488 489 case CLSET_BACKCHANNEL: 490 xprt = (SVCXPRT *)info; 491 xprt_register(xprt); 492 rc->rc_backchannel = info; 493 break; 494 495 case CLSET_TLS: 496 rc->rc_tls = true; 497 break; 498 499 default: 500 return (FALSE); 501 } 502 503 return (TRUE); 504 } 505 506 static void 507 clnt_reconnect_close(CLIENT *cl) 508 { 509 struct rc_data *rc = (struct rc_data *)cl->cl_private; 510 CLIENT *client; 511 512 mtx_lock(&rc->rc_lock); 513 514 if (rc->rc_closed) { 515 mtx_unlock(&rc->rc_lock); 516 return; 517 } 518 519 rc->rc_closed = TRUE; 520 client = rc->rc_client; 521 rc->rc_client = NULL; 522 523 mtx_unlock(&rc->rc_lock); 524 525 if (client) { 526 CLNT_CLOSE(client); 527 CLNT_RELEASE(client); 528 } 529 } 530 531 static void 532 clnt_reconnect_destroy(CLIENT *cl) 533 { 534 struct rc_data *rc = (struct rc_data *)cl->cl_private; 535 SVCXPRT *xprt; 536 537 if (rc->rc_client) 538 CLNT_DESTROY(rc->rc_client); 539 if (rc->rc_backchannel) { 540 xprt = (SVCXPRT *)rc->rc_backchannel; 541 xprt_unregister(xprt); 542 SVC_RELEASE(xprt); 543 } 544 crfree(rc->rc_ucred); 545 mtx_destroy(&rc->rc_lock); 546 mem_free(rc, sizeof(*rc)); 547 mem_free(cl, sizeof (CLIENT)); 548 } 549