1 /* 2 * linux/net/sunrpc/clnt.c 3 * 4 * This file contains the high-level RPC interface. 5 * It is modeled as a finite state machine to support both synchronous 6 * and asynchronous requests. 7 * 8 * - RPC header generation and argument serialization. 9 * - Credential refresh. 10 * - TCP connect handling. 11 * - Retry of operation when it is suspected the operation failed because 12 * of uid squashing on the server, or when the credentials were stale 13 * and need to be refreshed, or when a packet was damaged in transit. 14 * This may be have to be moved to the VFS layer. 15 * 16 * NB: BSD uses a more intelligent approach to guessing when a request 17 * or reply has been lost by keeping the RTO estimate for each procedure. 18 * We currently make do with a constant timeout value. 19 * 20 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 21 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 22 */ 23 24 #include <asm/system.h> 25 26 #include <linux/module.h> 27 #include <linux/types.h> 28 #include <linux/mm.h> 29 #include <linux/slab.h> 30 #include <linux/utsname.h> 31 32 #include <linux/sunrpc/clnt.h> 33 #include <linux/workqueue.h> 34 #include <linux/sunrpc/rpc_pipe_fs.h> 35 36 #include <linux/nfs.h> 37 38 39 #define RPC_SLACK_SPACE (1024) /* total overkill */ 40 41 #ifdef RPC_DEBUG 42 # define RPCDBG_FACILITY RPCDBG_CALL 43 #endif 44 45 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 46 47 48 static void call_start(struct rpc_task *task); 49 static void call_reserve(struct rpc_task *task); 50 static void call_reserveresult(struct rpc_task *task); 51 static void call_allocate(struct rpc_task *task); 52 static void call_encode(struct rpc_task *task); 53 static void call_decode(struct rpc_task *task); 54 static void call_bind(struct rpc_task *task); 55 static void call_bind_status(struct rpc_task *task); 56 static void call_transmit(struct rpc_task *task); 57 static void call_status(struct rpc_task *task); 58 static void call_refresh(struct rpc_task *task); 59 static void call_refreshresult(struct rpc_task *task); 60 static void call_timeout(struct rpc_task *task); 61 static void call_connect(struct rpc_task *task); 62 static void call_connect_status(struct rpc_task *task); 63 static u32 * call_header(struct rpc_task *task); 64 static u32 * call_verify(struct rpc_task *task); 65 66 67 static int 68 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name) 69 { 70 static uint32_t clntid; 71 int error; 72 73 if (dir_name == NULL) 74 return 0; 75 for (;;) { 76 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname), 77 "%s/clnt%x", dir_name, 78 (unsigned int)clntid++); 79 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0'; 80 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt); 81 if (!IS_ERR(clnt->cl_dentry)) 82 return 0; 83 error = PTR_ERR(clnt->cl_dentry); 84 if (error != -EEXIST) { 85 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n", 86 clnt->cl_pathname, error); 87 return error; 88 } 89 } 90 } 91 92 /* 93 * Create an RPC client 94 * FIXME: This should also take a flags argument (as in task->tk_flags). 95 * It's called (among others) from pmap_create_client, which may in 96 * turn be called by an async task. In this case, rpciod should not be 97 * made to sleep too long. 98 */ 99 struct rpc_clnt * 100 rpc_new_client(struct rpc_xprt *xprt, char *servname, 101 struct rpc_program *program, u32 vers, 102 rpc_authflavor_t flavor) 103 { 104 struct rpc_version *version; 105 struct rpc_clnt *clnt = NULL; 106 struct rpc_auth *auth; 107 int err; 108 int len; 109 110 dprintk("RPC: creating %s client for %s (xprt %p)\n", 111 program->name, servname, xprt); 112 113 err = -EINVAL; 114 if (!xprt) 115 goto out_err; 116 if (vers >= program->nrvers || !(version = program->version[vers])) 117 goto out_err; 118 119 err = -ENOMEM; 120 clnt = (struct rpc_clnt *) kmalloc(sizeof(*clnt), GFP_KERNEL); 121 if (!clnt) 122 goto out_err; 123 memset(clnt, 0, sizeof(*clnt)); 124 atomic_set(&clnt->cl_users, 0); 125 atomic_set(&clnt->cl_count, 1); 126 clnt->cl_parent = clnt; 127 128 clnt->cl_server = clnt->cl_inline_name; 129 len = strlen(servname) + 1; 130 if (len > sizeof(clnt->cl_inline_name)) { 131 char *buf = kmalloc(len, GFP_KERNEL); 132 if (buf != 0) 133 clnt->cl_server = buf; 134 else 135 len = sizeof(clnt->cl_inline_name); 136 } 137 strlcpy(clnt->cl_server, servname, len); 138 139 clnt->cl_xprt = xprt; 140 clnt->cl_procinfo = version->procs; 141 clnt->cl_maxproc = version->nrprocs; 142 clnt->cl_protname = program->name; 143 clnt->cl_pmap = &clnt->cl_pmap_default; 144 clnt->cl_port = xprt->addr.sin_port; 145 clnt->cl_prog = program->number; 146 clnt->cl_vers = version->number; 147 clnt->cl_prot = xprt->prot; 148 clnt->cl_stats = program->stats; 149 rpc_init_wait_queue(&clnt->cl_pmap_default.pm_bindwait, "bindwait"); 150 151 if (!clnt->cl_port) 152 clnt->cl_autobind = 1; 153 154 clnt->cl_rtt = &clnt->cl_rtt_default; 155 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval); 156 157 err = rpc_setup_pipedir(clnt, program->pipe_dir_name); 158 if (err < 0) 159 goto out_no_path; 160 161 auth = rpcauth_create(flavor, clnt); 162 if (IS_ERR(auth)) { 163 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", 164 flavor); 165 err = PTR_ERR(auth); 166 goto out_no_auth; 167 } 168 169 /* save the nodename */ 170 clnt->cl_nodelen = strlen(system_utsname.nodename); 171 if (clnt->cl_nodelen > UNX_MAXNODENAME) 172 clnt->cl_nodelen = UNX_MAXNODENAME; 173 memcpy(clnt->cl_nodename, system_utsname.nodename, clnt->cl_nodelen); 174 return clnt; 175 176 out_no_auth: 177 rpc_rmdir(clnt->cl_pathname); 178 out_no_path: 179 if (clnt->cl_server != clnt->cl_inline_name) 180 kfree(clnt->cl_server); 181 kfree(clnt); 182 out_err: 183 xprt_destroy(xprt); 184 return ERR_PTR(err); 185 } 186 187 /** 188 * Create an RPC client 189 * @xprt - pointer to xprt struct 190 * @servname - name of server 191 * @info - rpc_program 192 * @version - rpc_program version 193 * @authflavor - rpc_auth flavour to use 194 * 195 * Creates an RPC client structure, then pings the server in order to 196 * determine if it is up, and if it supports this program and version. 197 * 198 * This function should never be called by asynchronous tasks such as 199 * the portmapper. 200 */ 201 struct rpc_clnt *rpc_create_client(struct rpc_xprt *xprt, char *servname, 202 struct rpc_program *info, u32 version, rpc_authflavor_t authflavor) 203 { 204 struct rpc_clnt *clnt; 205 int err; 206 207 clnt = rpc_new_client(xprt, servname, info, version, authflavor); 208 if (IS_ERR(clnt)) 209 return clnt; 210 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); 211 if (err == 0) 212 return clnt; 213 rpc_shutdown_client(clnt); 214 return ERR_PTR(err); 215 } 216 217 /* 218 * This function clones the RPC client structure. It allows us to share the 219 * same transport while varying parameters such as the authentication 220 * flavour. 221 */ 222 struct rpc_clnt * 223 rpc_clone_client(struct rpc_clnt *clnt) 224 { 225 struct rpc_clnt *new; 226 227 new = (struct rpc_clnt *)kmalloc(sizeof(*new), GFP_KERNEL); 228 if (!new) 229 goto out_no_clnt; 230 memcpy(new, clnt, sizeof(*new)); 231 atomic_set(&new->cl_count, 1); 232 atomic_set(&new->cl_users, 0); 233 new->cl_parent = clnt; 234 atomic_inc(&clnt->cl_count); 235 /* Duplicate portmapper */ 236 rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait"); 237 /* Turn off autobind on clones */ 238 new->cl_autobind = 0; 239 new->cl_oneshot = 0; 240 new->cl_dead = 0; 241 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval); 242 if (new->cl_auth) 243 atomic_inc(&new->cl_auth->au_count); 244 new->cl_pmap = &new->cl_pmap_default; 245 rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait"); 246 return new; 247 out_no_clnt: 248 printk(KERN_INFO "RPC: out of memory in %s\n", __FUNCTION__); 249 return ERR_PTR(-ENOMEM); 250 } 251 252 /* 253 * Properly shut down an RPC client, terminating all outstanding 254 * requests. Note that we must be certain that cl_oneshot and 255 * cl_dead are cleared, or else the client would be destroyed 256 * when the last task releases it. 257 */ 258 int 259 rpc_shutdown_client(struct rpc_clnt *clnt) 260 { 261 dprintk("RPC: shutting down %s client for %s, tasks=%d\n", 262 clnt->cl_protname, clnt->cl_server, 263 atomic_read(&clnt->cl_users)); 264 265 while (atomic_read(&clnt->cl_users) > 0) { 266 /* Don't let rpc_release_client destroy us */ 267 clnt->cl_oneshot = 0; 268 clnt->cl_dead = 0; 269 rpc_killall_tasks(clnt); 270 sleep_on_timeout(&destroy_wait, 1*HZ); 271 } 272 273 if (atomic_read(&clnt->cl_users) < 0) { 274 printk(KERN_ERR "RPC: rpc_shutdown_client clnt %p tasks=%d\n", 275 clnt, atomic_read(&clnt->cl_users)); 276 #ifdef RPC_DEBUG 277 rpc_show_tasks(); 278 #endif 279 BUG(); 280 } 281 282 return rpc_destroy_client(clnt); 283 } 284 285 /* 286 * Delete an RPC client 287 */ 288 int 289 rpc_destroy_client(struct rpc_clnt *clnt) 290 { 291 if (!atomic_dec_and_test(&clnt->cl_count)) 292 return 1; 293 BUG_ON(atomic_read(&clnt->cl_users) != 0); 294 295 dprintk("RPC: destroying %s client for %s\n", 296 clnt->cl_protname, clnt->cl_server); 297 if (clnt->cl_auth) { 298 rpcauth_destroy(clnt->cl_auth); 299 clnt->cl_auth = NULL; 300 } 301 if (clnt->cl_parent != clnt) { 302 rpc_destroy_client(clnt->cl_parent); 303 goto out_free; 304 } 305 if (clnt->cl_pathname[0]) 306 rpc_rmdir(clnt->cl_pathname); 307 if (clnt->cl_xprt) { 308 xprt_destroy(clnt->cl_xprt); 309 clnt->cl_xprt = NULL; 310 } 311 if (clnt->cl_server != clnt->cl_inline_name) 312 kfree(clnt->cl_server); 313 out_free: 314 kfree(clnt); 315 return 0; 316 } 317 318 /* 319 * Release an RPC client 320 */ 321 void 322 rpc_release_client(struct rpc_clnt *clnt) 323 { 324 dprintk("RPC: rpc_release_client(%p, %d)\n", 325 clnt, atomic_read(&clnt->cl_users)); 326 327 if (!atomic_dec_and_test(&clnt->cl_users)) 328 return; 329 wake_up(&destroy_wait); 330 if (clnt->cl_oneshot || clnt->cl_dead) 331 rpc_destroy_client(clnt); 332 } 333 334 /** 335 * rpc_bind_new_program - bind a new RPC program to an existing client 336 * @old - old rpc_client 337 * @program - rpc program to set 338 * @vers - rpc program version 339 * 340 * Clones the rpc client and sets up a new RPC program. This is mainly 341 * of use for enabling different RPC programs to share the same transport. 342 * The Sun NFSv2/v3 ACL protocol can do this. 343 */ 344 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 345 struct rpc_program *program, 346 int vers) 347 { 348 struct rpc_clnt *clnt; 349 struct rpc_version *version; 350 int err; 351 352 BUG_ON(vers >= program->nrvers || !program->version[vers]); 353 version = program->version[vers]; 354 clnt = rpc_clone_client(old); 355 if (IS_ERR(clnt)) 356 goto out; 357 clnt->cl_procinfo = version->procs; 358 clnt->cl_maxproc = version->nrprocs; 359 clnt->cl_protname = program->name; 360 clnt->cl_prog = program->number; 361 clnt->cl_vers = version->number; 362 clnt->cl_stats = program->stats; 363 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); 364 if (err != 0) { 365 rpc_shutdown_client(clnt); 366 clnt = ERR_PTR(err); 367 } 368 out: 369 return clnt; 370 } 371 372 /* 373 * Default callback for async RPC calls 374 */ 375 static void 376 rpc_default_callback(struct rpc_task *task) 377 { 378 } 379 380 /* 381 * Export the signal mask handling for synchronous code that 382 * sleeps on RPC calls 383 */ 384 #define RPC_INTR_SIGNALS (sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGKILL)) 385 386 static void rpc_save_sigmask(sigset_t *oldset, int intr) 387 { 388 unsigned long sigallow = 0; 389 sigset_t sigmask; 390 391 /* Block all signals except those listed in sigallow */ 392 if (intr) 393 sigallow |= RPC_INTR_SIGNALS; 394 siginitsetinv(&sigmask, sigallow); 395 sigprocmask(SIG_BLOCK, &sigmask, oldset); 396 } 397 398 static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset) 399 { 400 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task)); 401 } 402 403 static inline void rpc_restore_sigmask(sigset_t *oldset) 404 { 405 sigprocmask(SIG_SETMASK, oldset, NULL); 406 } 407 408 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset) 409 { 410 rpc_save_sigmask(oldset, clnt->cl_intr); 411 } 412 413 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset) 414 { 415 rpc_restore_sigmask(oldset); 416 } 417 418 /* 419 * New rpc_call implementation 420 */ 421 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) 422 { 423 struct rpc_task *task; 424 sigset_t oldset; 425 int status; 426 427 /* If this client is slain all further I/O fails */ 428 if (clnt->cl_dead) 429 return -EIO; 430 431 BUG_ON(flags & RPC_TASK_ASYNC); 432 433 status = -ENOMEM; 434 task = rpc_new_task(clnt, NULL, flags); 435 if (task == NULL) 436 goto out; 437 438 /* Mask signals on RPC calls _and_ GSS_AUTH upcalls */ 439 rpc_task_sigmask(task, &oldset); 440 441 rpc_call_setup(task, msg, 0); 442 443 /* Set up the call info struct and execute the task */ 444 if (task->tk_status == 0) { 445 status = rpc_execute(task); 446 } else { 447 status = task->tk_status; 448 rpc_release_task(task); 449 } 450 451 rpc_restore_sigmask(&oldset); 452 out: 453 return status; 454 } 455 456 /* 457 * New rpc_call implementation 458 */ 459 int 460 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags, 461 rpc_action callback, void *data) 462 { 463 struct rpc_task *task; 464 sigset_t oldset; 465 int status; 466 467 /* If this client is slain all further I/O fails */ 468 if (clnt->cl_dead) 469 return -EIO; 470 471 flags |= RPC_TASK_ASYNC; 472 473 /* Create/initialize a new RPC task */ 474 if (!callback) 475 callback = rpc_default_callback; 476 status = -ENOMEM; 477 if (!(task = rpc_new_task(clnt, callback, flags))) 478 goto out; 479 task->tk_calldata = data; 480 481 /* Mask signals on GSS_AUTH upcalls */ 482 rpc_task_sigmask(task, &oldset); 483 484 rpc_call_setup(task, msg, 0); 485 486 /* Set up the call info struct and execute the task */ 487 status = task->tk_status; 488 if (status == 0) 489 rpc_execute(task); 490 else 491 rpc_release_task(task); 492 493 rpc_restore_sigmask(&oldset); 494 out: 495 return status; 496 } 497 498 499 void 500 rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags) 501 { 502 task->tk_msg = *msg; 503 task->tk_flags |= flags; 504 /* Bind the user cred */ 505 if (task->tk_msg.rpc_cred != NULL) 506 rpcauth_holdcred(task); 507 else 508 rpcauth_bindcred(task); 509 510 if (task->tk_status == 0) 511 task->tk_action = call_start; 512 else 513 task->tk_action = NULL; 514 } 515 516 void 517 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 518 { 519 struct rpc_xprt *xprt = clnt->cl_xprt; 520 if (xprt->ops->set_buffer_size) 521 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 522 } 523 524 /* 525 * Return size of largest payload RPC client can support, in bytes 526 * 527 * For stream transports, this is one RPC record fragment (see RFC 528 * 1831), as we don't support multi-record requests yet. For datagram 529 * transports, this is the size of an IP packet minus the IP, UDP, and 530 * RPC header sizes. 531 */ 532 size_t rpc_max_payload(struct rpc_clnt *clnt) 533 { 534 return clnt->cl_xprt->max_payload; 535 } 536 EXPORT_SYMBOL(rpc_max_payload); 537 538 /* 539 * Restart an (async) RPC call. Usually called from within the 540 * exit handler. 541 */ 542 void 543 rpc_restart_call(struct rpc_task *task) 544 { 545 if (RPC_ASSASSINATED(task)) 546 return; 547 548 task->tk_action = call_start; 549 } 550 551 /* 552 * 0. Initial state 553 * 554 * Other FSM states can be visited zero or more times, but 555 * this state is visited exactly once for each RPC. 556 */ 557 static void 558 call_start(struct rpc_task *task) 559 { 560 struct rpc_clnt *clnt = task->tk_client; 561 562 dprintk("RPC: %4d call_start %s%d proc %d (%s)\n", task->tk_pid, 563 clnt->cl_protname, clnt->cl_vers, task->tk_msg.rpc_proc->p_proc, 564 (RPC_IS_ASYNC(task) ? "async" : "sync")); 565 566 /* Increment call count */ 567 task->tk_msg.rpc_proc->p_count++; 568 clnt->cl_stats->rpccnt++; 569 task->tk_action = call_reserve; 570 } 571 572 /* 573 * 1. Reserve an RPC call slot 574 */ 575 static void 576 call_reserve(struct rpc_task *task) 577 { 578 dprintk("RPC: %4d call_reserve\n", task->tk_pid); 579 580 if (!rpcauth_uptodatecred(task)) { 581 task->tk_action = call_refresh; 582 return; 583 } 584 585 task->tk_status = 0; 586 task->tk_action = call_reserveresult; 587 xprt_reserve(task); 588 } 589 590 /* 591 * 1b. Grok the result of xprt_reserve() 592 */ 593 static void 594 call_reserveresult(struct rpc_task *task) 595 { 596 int status = task->tk_status; 597 598 dprintk("RPC: %4d call_reserveresult (status %d)\n", 599 task->tk_pid, task->tk_status); 600 601 /* 602 * After a call to xprt_reserve(), we must have either 603 * a request slot or else an error status. 604 */ 605 task->tk_status = 0; 606 if (status >= 0) { 607 if (task->tk_rqstp) { 608 task->tk_action = call_allocate; 609 return; 610 } 611 612 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 613 __FUNCTION__, status); 614 rpc_exit(task, -EIO); 615 return; 616 } 617 618 /* 619 * Even though there was an error, we may have acquired 620 * a request slot somehow. Make sure not to leak it. 621 */ 622 if (task->tk_rqstp) { 623 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 624 __FUNCTION__, status); 625 xprt_release(task); 626 } 627 628 switch (status) { 629 case -EAGAIN: /* woken up; retry */ 630 task->tk_action = call_reserve; 631 return; 632 case -EIO: /* probably a shutdown */ 633 break; 634 default: 635 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 636 __FUNCTION__, status); 637 break; 638 } 639 rpc_exit(task, status); 640 } 641 642 /* 643 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. 644 * (Note: buffer memory is freed in rpc_task_release). 645 */ 646 static void 647 call_allocate(struct rpc_task *task) 648 { 649 unsigned int bufsiz; 650 651 dprintk("RPC: %4d call_allocate (status %d)\n", 652 task->tk_pid, task->tk_status); 653 task->tk_action = call_bind; 654 if (task->tk_buffer) 655 return; 656 657 /* FIXME: compute buffer requirements more exactly using 658 * auth->au_wslack */ 659 bufsiz = task->tk_msg.rpc_proc->p_bufsiz + RPC_SLACK_SPACE; 660 661 if (rpc_malloc(task, bufsiz << 1) != NULL) 662 return; 663 printk(KERN_INFO "RPC: buffer allocation failed for task %p\n", task); 664 665 if (RPC_IS_ASYNC(task) || !signalled()) { 666 xprt_release(task); 667 task->tk_action = call_reserve; 668 rpc_delay(task, HZ>>4); 669 return; 670 } 671 672 rpc_exit(task, -ERESTARTSYS); 673 } 674 675 /* 676 * 3. Encode arguments of an RPC call 677 */ 678 static void 679 call_encode(struct rpc_task *task) 680 { 681 struct rpc_rqst *req = task->tk_rqstp; 682 struct xdr_buf *sndbuf = &req->rq_snd_buf; 683 struct xdr_buf *rcvbuf = &req->rq_rcv_buf; 684 unsigned int bufsiz; 685 kxdrproc_t encode; 686 u32 *p; 687 688 dprintk("RPC: %4d call_encode (status %d)\n", 689 task->tk_pid, task->tk_status); 690 691 /* Default buffer setup */ 692 bufsiz = task->tk_bufsize >> 1; 693 sndbuf->head[0].iov_base = (void *)task->tk_buffer; 694 sndbuf->head[0].iov_len = bufsiz; 695 sndbuf->tail[0].iov_len = 0; 696 sndbuf->page_len = 0; 697 sndbuf->len = 0; 698 sndbuf->buflen = bufsiz; 699 rcvbuf->head[0].iov_base = (void *)((char *)task->tk_buffer + bufsiz); 700 rcvbuf->head[0].iov_len = bufsiz; 701 rcvbuf->tail[0].iov_len = 0; 702 rcvbuf->page_len = 0; 703 rcvbuf->len = 0; 704 rcvbuf->buflen = bufsiz; 705 706 /* Encode header and provided arguments */ 707 encode = task->tk_msg.rpc_proc->p_encode; 708 if (!(p = call_header(task))) { 709 printk(KERN_INFO "RPC: call_header failed, exit EIO\n"); 710 rpc_exit(task, -EIO); 711 return; 712 } 713 if (encode == NULL) 714 return; 715 716 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 717 task->tk_msg.rpc_argp); 718 if (task->tk_status == -ENOMEM) { 719 /* XXX: Is this sane? */ 720 rpc_delay(task, 3*HZ); 721 task->tk_status = -EAGAIN; 722 } 723 } 724 725 /* 726 * 4. Get the server port number if not yet set 727 */ 728 static void 729 call_bind(struct rpc_task *task) 730 { 731 struct rpc_clnt *clnt = task->tk_client; 732 733 dprintk("RPC: %4d call_bind (status %d)\n", 734 task->tk_pid, task->tk_status); 735 736 task->tk_action = call_connect; 737 if (!clnt->cl_port) { 738 task->tk_action = call_bind_status; 739 task->tk_timeout = task->tk_xprt->bind_timeout; 740 rpc_getport(task, clnt); 741 } 742 } 743 744 /* 745 * 4a. Sort out bind result 746 */ 747 static void 748 call_bind_status(struct rpc_task *task) 749 { 750 int status = -EACCES; 751 752 if (task->tk_status >= 0) { 753 dprintk("RPC: %4d call_bind_status (status %d)\n", 754 task->tk_pid, task->tk_status); 755 task->tk_status = 0; 756 task->tk_action = call_connect; 757 return; 758 } 759 760 switch (task->tk_status) { 761 case -EACCES: 762 dprintk("RPC: %4d remote rpcbind: RPC program/version unavailable\n", 763 task->tk_pid); 764 rpc_delay(task, 3*HZ); 765 goto retry_bind; 766 case -ETIMEDOUT: 767 dprintk("RPC: %4d rpcbind request timed out\n", 768 task->tk_pid); 769 if (RPC_IS_SOFT(task)) { 770 status = -EIO; 771 break; 772 } 773 goto retry_bind; 774 case -EPFNOSUPPORT: 775 dprintk("RPC: %4d remote rpcbind service unavailable\n", 776 task->tk_pid); 777 break; 778 case -EPROTONOSUPPORT: 779 dprintk("RPC: %4d remote rpcbind version 2 unavailable\n", 780 task->tk_pid); 781 break; 782 default: 783 dprintk("RPC: %4d unrecognized rpcbind error (%d)\n", 784 task->tk_pid, -task->tk_status); 785 status = -EIO; 786 break; 787 } 788 789 rpc_exit(task, status); 790 return; 791 792 retry_bind: 793 task->tk_status = 0; 794 task->tk_action = call_bind; 795 return; 796 } 797 798 /* 799 * 4b. Connect to the RPC server 800 */ 801 static void 802 call_connect(struct rpc_task *task) 803 { 804 struct rpc_xprt *xprt = task->tk_xprt; 805 806 dprintk("RPC: %4d call_connect xprt %p %s connected\n", 807 task->tk_pid, xprt, 808 (xprt_connected(xprt) ? "is" : "is not")); 809 810 task->tk_action = call_transmit; 811 if (!xprt_connected(xprt)) { 812 task->tk_action = call_connect_status; 813 if (task->tk_status < 0) 814 return; 815 xprt_connect(task); 816 } 817 } 818 819 /* 820 * 4c. Sort out connect result 821 */ 822 static void 823 call_connect_status(struct rpc_task *task) 824 { 825 struct rpc_clnt *clnt = task->tk_client; 826 int status = task->tk_status; 827 828 dprintk("RPC: %5u call_connect_status (status %d)\n", 829 task->tk_pid, task->tk_status); 830 831 task->tk_status = 0; 832 if (status >= 0) { 833 clnt->cl_stats->netreconn++; 834 task->tk_action = call_transmit; 835 return; 836 } 837 838 /* Something failed: remote service port may have changed */ 839 if (clnt->cl_autobind) 840 clnt->cl_port = 0; 841 842 switch (status) { 843 case -ENOTCONN: 844 case -ETIMEDOUT: 845 case -EAGAIN: 846 task->tk_action = call_bind; 847 break; 848 default: 849 rpc_exit(task, -EIO); 850 break; 851 } 852 } 853 854 /* 855 * 5. Transmit the RPC request, and wait for reply 856 */ 857 static void 858 call_transmit(struct rpc_task *task) 859 { 860 dprintk("RPC: %4d call_transmit (status %d)\n", 861 task->tk_pid, task->tk_status); 862 863 task->tk_action = call_status; 864 if (task->tk_status < 0) 865 return; 866 task->tk_status = xprt_prepare_transmit(task); 867 if (task->tk_status != 0) 868 return; 869 /* Encode here so that rpcsec_gss can use correct sequence number. */ 870 if (task->tk_rqstp->rq_bytes_sent == 0) { 871 call_encode(task); 872 /* Did the encode result in an error condition? */ 873 if (task->tk_status != 0) 874 goto out_nosend; 875 } 876 xprt_transmit(task); 877 if (task->tk_status < 0) 878 return; 879 if (!task->tk_msg.rpc_proc->p_decode) { 880 task->tk_action = NULL; 881 rpc_wake_up_task(task); 882 } 883 return; 884 out_nosend: 885 /* release socket write lock before attempting to handle error */ 886 xprt_abort_transmit(task); 887 } 888 889 /* 890 * 6. Sort out the RPC call status 891 */ 892 static void 893 call_status(struct rpc_task *task) 894 { 895 struct rpc_clnt *clnt = task->tk_client; 896 struct rpc_rqst *req = task->tk_rqstp; 897 int status; 898 899 if (req->rq_received > 0 && !req->rq_bytes_sent) 900 task->tk_status = req->rq_received; 901 902 dprintk("RPC: %4d call_status (status %d)\n", 903 task->tk_pid, task->tk_status); 904 905 status = task->tk_status; 906 if (status >= 0) { 907 task->tk_action = call_decode; 908 return; 909 } 910 911 task->tk_status = 0; 912 switch(status) { 913 case -ETIMEDOUT: 914 task->tk_action = call_timeout; 915 break; 916 case -ECONNREFUSED: 917 case -ENOTCONN: 918 req->rq_bytes_sent = 0; 919 if (clnt->cl_autobind) 920 clnt->cl_port = 0; 921 task->tk_action = call_bind; 922 break; 923 case -EAGAIN: 924 task->tk_action = call_transmit; 925 break; 926 case -EIO: 927 /* shutdown or soft timeout */ 928 rpc_exit(task, status); 929 break; 930 default: 931 if (clnt->cl_chatty) 932 printk("%s: RPC call returned error %d\n", 933 clnt->cl_protname, -status); 934 rpc_exit(task, status); 935 break; 936 } 937 } 938 939 /* 940 * 6a. Handle RPC timeout 941 * We do not release the request slot, so we keep using the 942 * same XID for all retransmits. 943 */ 944 static void 945 call_timeout(struct rpc_task *task) 946 { 947 struct rpc_clnt *clnt = task->tk_client; 948 949 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 950 dprintk("RPC: %4d call_timeout (minor)\n", task->tk_pid); 951 goto retry; 952 } 953 954 dprintk("RPC: %4d call_timeout (major)\n", task->tk_pid); 955 if (RPC_IS_SOFT(task)) { 956 if (clnt->cl_chatty) 957 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 958 clnt->cl_protname, clnt->cl_server); 959 rpc_exit(task, -EIO); 960 return; 961 } 962 963 if (clnt->cl_chatty && !(task->tk_flags & RPC_CALL_MAJORSEEN)) { 964 task->tk_flags |= RPC_CALL_MAJORSEEN; 965 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 966 clnt->cl_protname, clnt->cl_server); 967 } 968 if (clnt->cl_autobind) 969 clnt->cl_port = 0; 970 971 retry: 972 clnt->cl_stats->rpcretrans++; 973 task->tk_action = call_bind; 974 task->tk_status = 0; 975 } 976 977 /* 978 * 7. Decode the RPC reply 979 */ 980 static void 981 call_decode(struct rpc_task *task) 982 { 983 struct rpc_clnt *clnt = task->tk_client; 984 struct rpc_rqst *req = task->tk_rqstp; 985 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; 986 u32 *p; 987 988 dprintk("RPC: %4d call_decode (status %d)\n", 989 task->tk_pid, task->tk_status); 990 991 if (clnt->cl_chatty && (task->tk_flags & RPC_CALL_MAJORSEEN)) { 992 printk(KERN_NOTICE "%s: server %s OK\n", 993 clnt->cl_protname, clnt->cl_server); 994 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 995 } 996 997 if (task->tk_status < 12) { 998 if (!RPC_IS_SOFT(task)) { 999 task->tk_action = call_bind; 1000 clnt->cl_stats->rpcretrans++; 1001 goto out_retry; 1002 } 1003 printk(KERN_WARNING "%s: too small RPC reply size (%d bytes)\n", 1004 clnt->cl_protname, task->tk_status); 1005 rpc_exit(task, -EIO); 1006 return; 1007 } 1008 1009 req->rq_rcv_buf.len = req->rq_private_buf.len; 1010 1011 /* Check that the softirq receive buffer is valid */ 1012 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1013 sizeof(req->rq_rcv_buf)) != 0); 1014 1015 /* Verify the RPC header */ 1016 if (!(p = call_verify(task))) { 1017 if (task->tk_action == NULL) 1018 return; 1019 goto out_retry; 1020 } 1021 1022 task->tk_action = NULL; 1023 1024 if (decode) 1025 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1026 task->tk_msg.rpc_resp); 1027 dprintk("RPC: %4d call_decode result %d\n", task->tk_pid, 1028 task->tk_status); 1029 return; 1030 out_retry: 1031 req->rq_received = req->rq_private_buf.len = 0; 1032 task->tk_status = 0; 1033 } 1034 1035 /* 1036 * 8. Refresh the credentials if rejected by the server 1037 */ 1038 static void 1039 call_refresh(struct rpc_task *task) 1040 { 1041 dprintk("RPC: %4d call_refresh\n", task->tk_pid); 1042 1043 xprt_release(task); /* Must do to obtain new XID */ 1044 task->tk_action = call_refreshresult; 1045 task->tk_status = 0; 1046 task->tk_client->cl_stats->rpcauthrefresh++; 1047 rpcauth_refreshcred(task); 1048 } 1049 1050 /* 1051 * 8a. Process the results of a credential refresh 1052 */ 1053 static void 1054 call_refreshresult(struct rpc_task *task) 1055 { 1056 int status = task->tk_status; 1057 dprintk("RPC: %4d call_refreshresult (status %d)\n", 1058 task->tk_pid, task->tk_status); 1059 1060 task->tk_status = 0; 1061 task->tk_action = call_reserve; 1062 if (status >= 0 && rpcauth_uptodatecred(task)) 1063 return; 1064 if (status == -EACCES) { 1065 rpc_exit(task, -EACCES); 1066 return; 1067 } 1068 task->tk_action = call_refresh; 1069 if (status != -ETIMEDOUT) 1070 rpc_delay(task, 3*HZ); 1071 return; 1072 } 1073 1074 /* 1075 * Call header serialization 1076 */ 1077 static u32 * 1078 call_header(struct rpc_task *task) 1079 { 1080 struct rpc_clnt *clnt = task->tk_client; 1081 struct rpc_rqst *req = task->tk_rqstp; 1082 u32 *p = req->rq_svec[0].iov_base; 1083 1084 /* FIXME: check buffer size? */ 1085 1086 p = xprt_skip_transport_header(task->tk_xprt, p); 1087 *p++ = req->rq_xid; /* XID */ 1088 *p++ = htonl(RPC_CALL); /* CALL */ 1089 *p++ = htonl(RPC_VERSION); /* RPC version */ 1090 *p++ = htonl(clnt->cl_prog); /* program number */ 1091 *p++ = htonl(clnt->cl_vers); /* program version */ 1092 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 1093 p = rpcauth_marshcred(task, p); 1094 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 1095 return p; 1096 } 1097 1098 /* 1099 * Reply header verification 1100 */ 1101 static u32 * 1102 call_verify(struct rpc_task *task) 1103 { 1104 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1105 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1106 u32 *p = iov->iov_base, n; 1107 int error = -EACCES; 1108 1109 if ((len -= 3) < 0) 1110 goto out_overflow; 1111 p += 1; /* skip XID */ 1112 1113 if ((n = ntohl(*p++)) != RPC_REPLY) { 1114 printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n); 1115 goto out_retry; 1116 } 1117 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1118 if (--len < 0) 1119 goto out_overflow; 1120 switch ((n = ntohl(*p++))) { 1121 case RPC_AUTH_ERROR: 1122 break; 1123 case RPC_MISMATCH: 1124 dprintk("%s: RPC call version mismatch!\n", __FUNCTION__); 1125 error = -EPROTONOSUPPORT; 1126 goto out_err; 1127 default: 1128 dprintk("%s: RPC call rejected, unknown error: %x\n", __FUNCTION__, n); 1129 goto out_eio; 1130 } 1131 if (--len < 0) 1132 goto out_overflow; 1133 switch ((n = ntohl(*p++))) { 1134 case RPC_AUTH_REJECTEDCRED: 1135 case RPC_AUTH_REJECTEDVERF: 1136 case RPCSEC_GSS_CREDPROBLEM: 1137 case RPCSEC_GSS_CTXPROBLEM: 1138 if (!task->tk_cred_retry) 1139 break; 1140 task->tk_cred_retry--; 1141 dprintk("RPC: %4d call_verify: retry stale creds\n", 1142 task->tk_pid); 1143 rpcauth_invalcred(task); 1144 task->tk_action = call_refresh; 1145 return NULL; 1146 case RPC_AUTH_BADCRED: 1147 case RPC_AUTH_BADVERF: 1148 /* possibly garbled cred/verf? */ 1149 if (!task->tk_garb_retry) 1150 break; 1151 task->tk_garb_retry--; 1152 dprintk("RPC: %4d call_verify: retry garbled creds\n", 1153 task->tk_pid); 1154 task->tk_action = call_bind; 1155 return NULL; 1156 case RPC_AUTH_TOOWEAK: 1157 printk(KERN_NOTICE "call_verify: server requires stronger " 1158 "authentication.\n"); 1159 break; 1160 default: 1161 printk(KERN_WARNING "call_verify: unknown auth error: %x\n", n); 1162 error = -EIO; 1163 } 1164 dprintk("RPC: %4d call_verify: call rejected %d\n", 1165 task->tk_pid, n); 1166 goto out_err; 1167 } 1168 if (!(p = rpcauth_checkverf(task, p))) { 1169 printk(KERN_WARNING "call_verify: auth check failed\n"); 1170 goto out_retry; /* bad verifier, retry */ 1171 } 1172 len = p - (u32 *)iov->iov_base - 1; 1173 if (len < 0) 1174 goto out_overflow; 1175 switch ((n = ntohl(*p++))) { 1176 case RPC_SUCCESS: 1177 return p; 1178 case RPC_PROG_UNAVAIL: 1179 dprintk("RPC: call_verify: program %u is unsupported by server %s\n", 1180 (unsigned int)task->tk_client->cl_prog, 1181 task->tk_client->cl_server); 1182 error = -EPFNOSUPPORT; 1183 goto out_err; 1184 case RPC_PROG_MISMATCH: 1185 dprintk("RPC: call_verify: program %u, version %u unsupported by server %s\n", 1186 (unsigned int)task->tk_client->cl_prog, 1187 (unsigned int)task->tk_client->cl_vers, 1188 task->tk_client->cl_server); 1189 error = -EPROTONOSUPPORT; 1190 goto out_err; 1191 case RPC_PROC_UNAVAIL: 1192 dprintk("RPC: call_verify: proc %p unsupported by program %u, version %u on server %s\n", 1193 task->tk_msg.rpc_proc, 1194 task->tk_client->cl_prog, 1195 task->tk_client->cl_vers, 1196 task->tk_client->cl_server); 1197 error = -EOPNOTSUPP; 1198 goto out_err; 1199 case RPC_GARBAGE_ARGS: 1200 dprintk("RPC: %4d %s: server saw garbage\n", task->tk_pid, __FUNCTION__); 1201 break; /* retry */ 1202 default: 1203 printk(KERN_WARNING "call_verify: server accept status: %x\n", n); 1204 /* Also retry */ 1205 } 1206 1207 out_retry: 1208 task->tk_client->cl_stats->rpcgarbage++; 1209 if (task->tk_garb_retry) { 1210 task->tk_garb_retry--; 1211 dprintk("RPC %s: retrying %4d\n", __FUNCTION__, task->tk_pid); 1212 task->tk_action = call_bind; 1213 return NULL; 1214 } 1215 printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__); 1216 out_eio: 1217 error = -EIO; 1218 out_err: 1219 rpc_exit(task, error); 1220 return NULL; 1221 out_overflow: 1222 printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__); 1223 goto out_retry; 1224 } 1225 1226 static int rpcproc_encode_null(void *rqstp, u32 *data, void *obj) 1227 { 1228 return 0; 1229 } 1230 1231 static int rpcproc_decode_null(void *rqstp, u32 *data, void *obj) 1232 { 1233 return 0; 1234 } 1235 1236 static struct rpc_procinfo rpcproc_null = { 1237 .p_encode = rpcproc_encode_null, 1238 .p_decode = rpcproc_decode_null, 1239 }; 1240 1241 int rpc_ping(struct rpc_clnt *clnt, int flags) 1242 { 1243 struct rpc_message msg = { 1244 .rpc_proc = &rpcproc_null, 1245 }; 1246 int err; 1247 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1248 err = rpc_call_sync(clnt, &msg, flags); 1249 put_rpccred(msg.rpc_cred); 1250 return err; 1251 } 1252