1 /* 2 * linux/net/sunrpc/rpcclnt.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/in.h> 31 #include <linux/utsname.h> 32 33 #include <linux/sunrpc/clnt.h> 34 #include <linux/workqueue.h> 35 #include <linux/sunrpc/rpc_pipe_fs.h> 36 37 #include <linux/nfs.h> 38 39 40 #define RPC_SLACK_SPACE (1024) /* total overkill */ 41 42 #ifdef RPC_DEBUG 43 # define RPCDBG_FACILITY RPCDBG_CALL 44 #endif 45 46 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 47 48 49 static void call_start(struct rpc_task *task); 50 static void call_reserve(struct rpc_task *task); 51 static void call_reserveresult(struct rpc_task *task); 52 static void call_allocate(struct rpc_task *task); 53 static void call_encode(struct rpc_task *task); 54 static void call_decode(struct rpc_task *task); 55 static void call_bind(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; 520 521 xprt->sndsize = 0; 522 if (sndsize) 523 xprt->sndsize = sndsize + RPC_SLACK_SPACE; 524 xprt->rcvsize = 0; 525 if (rcvsize) 526 xprt->rcvsize = rcvsize + RPC_SLACK_SPACE; 527 if (xprt_connected(xprt)) 528 xprt_sock_setbufsize(xprt); 529 } 530 531 /* 532 * Return size of largest payload RPC client can support, in bytes 533 * 534 * For stream transports, this is one RPC record fragment (see RFC 535 * 1831), as we don't support multi-record requests yet. For datagram 536 * transports, this is the size of an IP packet minus the IP, UDP, and 537 * RPC header sizes. 538 */ 539 size_t rpc_max_payload(struct rpc_clnt *clnt) 540 { 541 return clnt->cl_xprt->max_payload; 542 } 543 EXPORT_SYMBOL(rpc_max_payload); 544 545 /* 546 * Restart an (async) RPC call. Usually called from within the 547 * exit handler. 548 */ 549 void 550 rpc_restart_call(struct rpc_task *task) 551 { 552 if (RPC_ASSASSINATED(task)) 553 return; 554 555 task->tk_action = call_start; 556 } 557 558 /* 559 * 0. Initial state 560 * 561 * Other FSM states can be visited zero or more times, but 562 * this state is visited exactly once for each RPC. 563 */ 564 static void 565 call_start(struct rpc_task *task) 566 { 567 struct rpc_clnt *clnt = task->tk_client; 568 569 dprintk("RPC: %4d call_start %s%d proc %d (%s)\n", task->tk_pid, 570 clnt->cl_protname, clnt->cl_vers, task->tk_msg.rpc_proc->p_proc, 571 (RPC_IS_ASYNC(task) ? "async" : "sync")); 572 573 /* Increment call count */ 574 task->tk_msg.rpc_proc->p_count++; 575 clnt->cl_stats->rpccnt++; 576 task->tk_action = call_reserve; 577 } 578 579 /* 580 * 1. Reserve an RPC call slot 581 */ 582 static void 583 call_reserve(struct rpc_task *task) 584 { 585 dprintk("RPC: %4d call_reserve\n", task->tk_pid); 586 587 if (!rpcauth_uptodatecred(task)) { 588 task->tk_action = call_refresh; 589 return; 590 } 591 592 task->tk_status = 0; 593 task->tk_action = call_reserveresult; 594 xprt_reserve(task); 595 } 596 597 /* 598 * 1b. Grok the result of xprt_reserve() 599 */ 600 static void 601 call_reserveresult(struct rpc_task *task) 602 { 603 int status = task->tk_status; 604 605 dprintk("RPC: %4d call_reserveresult (status %d)\n", 606 task->tk_pid, task->tk_status); 607 608 /* 609 * After a call to xprt_reserve(), we must have either 610 * a request slot or else an error status. 611 */ 612 task->tk_status = 0; 613 if (status >= 0) { 614 if (task->tk_rqstp) { 615 task->tk_action = call_allocate; 616 return; 617 } 618 619 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 620 __FUNCTION__, status); 621 rpc_exit(task, -EIO); 622 return; 623 } 624 625 /* 626 * Even though there was an error, we may have acquired 627 * a request slot somehow. Make sure not to leak it. 628 */ 629 if (task->tk_rqstp) { 630 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 631 __FUNCTION__, status); 632 xprt_release(task); 633 } 634 635 switch (status) { 636 case -EAGAIN: /* woken up; retry */ 637 task->tk_action = call_reserve; 638 return; 639 case -EIO: /* probably a shutdown */ 640 break; 641 default: 642 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 643 __FUNCTION__, status); 644 break; 645 } 646 rpc_exit(task, status); 647 } 648 649 /* 650 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. 651 * (Note: buffer memory is freed in rpc_task_release). 652 */ 653 static void 654 call_allocate(struct rpc_task *task) 655 { 656 unsigned int bufsiz; 657 658 dprintk("RPC: %4d call_allocate (status %d)\n", 659 task->tk_pid, task->tk_status); 660 task->tk_action = call_bind; 661 if (task->tk_buffer) 662 return; 663 664 /* FIXME: compute buffer requirements more exactly using 665 * auth->au_wslack */ 666 bufsiz = task->tk_msg.rpc_proc->p_bufsiz + RPC_SLACK_SPACE; 667 668 if (rpc_malloc(task, bufsiz << 1) != NULL) 669 return; 670 printk(KERN_INFO "RPC: buffer allocation failed for task %p\n", task); 671 672 if (RPC_IS_ASYNC(task) || !signalled()) { 673 xprt_release(task); 674 task->tk_action = call_reserve; 675 rpc_delay(task, HZ>>4); 676 return; 677 } 678 679 rpc_exit(task, -ERESTARTSYS); 680 } 681 682 /* 683 * 3. Encode arguments of an RPC call 684 */ 685 static void 686 call_encode(struct rpc_task *task) 687 { 688 struct rpc_clnt *clnt = task->tk_client; 689 struct rpc_rqst *req = task->tk_rqstp; 690 struct xdr_buf *sndbuf = &req->rq_snd_buf; 691 struct xdr_buf *rcvbuf = &req->rq_rcv_buf; 692 unsigned int bufsiz; 693 kxdrproc_t encode; 694 int status; 695 u32 *p; 696 697 dprintk("RPC: %4d call_encode (status %d)\n", 698 task->tk_pid, task->tk_status); 699 700 /* Default buffer setup */ 701 bufsiz = task->tk_bufsize >> 1; 702 sndbuf->head[0].iov_base = (void *)task->tk_buffer; 703 sndbuf->head[0].iov_len = bufsiz; 704 sndbuf->tail[0].iov_len = 0; 705 sndbuf->page_len = 0; 706 sndbuf->len = 0; 707 sndbuf->buflen = bufsiz; 708 rcvbuf->head[0].iov_base = (void *)((char *)task->tk_buffer + bufsiz); 709 rcvbuf->head[0].iov_len = bufsiz; 710 rcvbuf->tail[0].iov_len = 0; 711 rcvbuf->page_len = 0; 712 rcvbuf->len = 0; 713 rcvbuf->buflen = bufsiz; 714 715 /* Encode header and provided arguments */ 716 encode = task->tk_msg.rpc_proc->p_encode; 717 if (!(p = call_header(task))) { 718 printk(KERN_INFO "RPC: call_header failed, exit EIO\n"); 719 rpc_exit(task, -EIO); 720 return; 721 } 722 if (encode && (status = rpcauth_wrap_req(task, encode, req, p, 723 task->tk_msg.rpc_argp)) < 0) { 724 printk(KERN_WARNING "%s: can't encode arguments: %d\n", 725 clnt->cl_protname, -status); 726 rpc_exit(task, status); 727 } 728 } 729 730 /* 731 * 4. Get the server port number if not yet set 732 */ 733 static void 734 call_bind(struct rpc_task *task) 735 { 736 struct rpc_clnt *clnt = task->tk_client; 737 struct rpc_xprt *xprt = clnt->cl_xprt; 738 739 dprintk("RPC: %4d call_bind xprt %p %s connected\n", task->tk_pid, 740 xprt, (xprt_connected(xprt) ? "is" : "is not")); 741 742 task->tk_action = (xprt_connected(xprt)) ? call_transmit : call_connect; 743 744 if (!clnt->cl_port) { 745 task->tk_action = call_connect; 746 task->tk_timeout = RPC_CONNECT_TIMEOUT; 747 rpc_getport(task, clnt); 748 } 749 } 750 751 /* 752 * 4a. Connect to the RPC server (TCP case) 753 */ 754 static void 755 call_connect(struct rpc_task *task) 756 { 757 struct rpc_clnt *clnt = task->tk_client; 758 759 dprintk("RPC: %4d call_connect status %d\n", 760 task->tk_pid, task->tk_status); 761 762 if (xprt_connected(clnt->cl_xprt)) { 763 task->tk_action = call_transmit; 764 return; 765 } 766 task->tk_action = call_connect_status; 767 if (task->tk_status < 0) 768 return; 769 xprt_connect(task); 770 } 771 772 /* 773 * 4b. Sort out connect result 774 */ 775 static void 776 call_connect_status(struct rpc_task *task) 777 { 778 struct rpc_clnt *clnt = task->tk_client; 779 int status = task->tk_status; 780 781 task->tk_status = 0; 782 if (status >= 0) { 783 clnt->cl_stats->netreconn++; 784 task->tk_action = call_transmit; 785 return; 786 } 787 788 /* Something failed: we may have to rebind */ 789 if (clnt->cl_autobind) 790 clnt->cl_port = 0; 791 switch (status) { 792 case -ENOTCONN: 793 case -ETIMEDOUT: 794 case -EAGAIN: 795 task->tk_action = (clnt->cl_port == 0) ? call_bind : call_connect; 796 break; 797 default: 798 rpc_exit(task, -EIO); 799 } 800 } 801 802 /* 803 * 5. Transmit the RPC request, and wait for reply 804 */ 805 static void 806 call_transmit(struct rpc_task *task) 807 { 808 dprintk("RPC: %4d call_transmit (status %d)\n", 809 task->tk_pid, task->tk_status); 810 811 task->tk_action = call_status; 812 if (task->tk_status < 0) 813 return; 814 task->tk_status = xprt_prepare_transmit(task); 815 if (task->tk_status != 0) 816 return; 817 /* Encode here so that rpcsec_gss can use correct sequence number. */ 818 if (!task->tk_rqstp->rq_bytes_sent) 819 call_encode(task); 820 if (task->tk_status < 0) 821 return; 822 xprt_transmit(task); 823 if (task->tk_status < 0) 824 return; 825 if (!task->tk_msg.rpc_proc->p_decode) { 826 task->tk_action = NULL; 827 rpc_wake_up_task(task); 828 } 829 } 830 831 /* 832 * 6. Sort out the RPC call status 833 */ 834 static void 835 call_status(struct rpc_task *task) 836 { 837 struct rpc_clnt *clnt = task->tk_client; 838 struct rpc_rqst *req = task->tk_rqstp; 839 int status; 840 841 if (req->rq_received > 0 && !req->rq_bytes_sent) 842 task->tk_status = req->rq_received; 843 844 dprintk("RPC: %4d call_status (status %d)\n", 845 task->tk_pid, task->tk_status); 846 847 status = task->tk_status; 848 if (status >= 0) { 849 task->tk_action = call_decode; 850 return; 851 } 852 853 task->tk_status = 0; 854 switch(status) { 855 case -ETIMEDOUT: 856 task->tk_action = call_timeout; 857 break; 858 case -ECONNREFUSED: 859 case -ENOTCONN: 860 req->rq_bytes_sent = 0; 861 if (clnt->cl_autobind) 862 clnt->cl_port = 0; 863 task->tk_action = call_bind; 864 break; 865 case -EAGAIN: 866 task->tk_action = call_transmit; 867 break; 868 case -EIO: 869 /* shutdown or soft timeout */ 870 rpc_exit(task, status); 871 break; 872 default: 873 if (clnt->cl_chatty) 874 printk("%s: RPC call returned error %d\n", 875 clnt->cl_protname, -status); 876 rpc_exit(task, status); 877 break; 878 } 879 } 880 881 /* 882 * 6a. Handle RPC timeout 883 * We do not release the request slot, so we keep using the 884 * same XID for all retransmits. 885 */ 886 static void 887 call_timeout(struct rpc_task *task) 888 { 889 struct rpc_clnt *clnt = task->tk_client; 890 891 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 892 dprintk("RPC: %4d call_timeout (minor)\n", task->tk_pid); 893 goto retry; 894 } 895 896 dprintk("RPC: %4d call_timeout (major)\n", task->tk_pid); 897 if (RPC_IS_SOFT(task)) { 898 if (clnt->cl_chatty) 899 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 900 clnt->cl_protname, clnt->cl_server); 901 rpc_exit(task, -EIO); 902 return; 903 } 904 905 if (clnt->cl_chatty && !(task->tk_flags & RPC_CALL_MAJORSEEN)) { 906 task->tk_flags |= RPC_CALL_MAJORSEEN; 907 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 908 clnt->cl_protname, clnt->cl_server); 909 } 910 if (clnt->cl_autobind) 911 clnt->cl_port = 0; 912 913 retry: 914 clnt->cl_stats->rpcretrans++; 915 task->tk_action = call_bind; 916 task->tk_status = 0; 917 } 918 919 /* 920 * 7. Decode the RPC reply 921 */ 922 static void 923 call_decode(struct rpc_task *task) 924 { 925 struct rpc_clnt *clnt = task->tk_client; 926 struct rpc_rqst *req = task->tk_rqstp; 927 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; 928 u32 *p; 929 930 dprintk("RPC: %4d call_decode (status %d)\n", 931 task->tk_pid, task->tk_status); 932 933 if (clnt->cl_chatty && (task->tk_flags & RPC_CALL_MAJORSEEN)) { 934 printk(KERN_NOTICE "%s: server %s OK\n", 935 clnt->cl_protname, clnt->cl_server); 936 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 937 } 938 939 if (task->tk_status < 12) { 940 if (!RPC_IS_SOFT(task)) { 941 task->tk_action = call_bind; 942 clnt->cl_stats->rpcretrans++; 943 goto out_retry; 944 } 945 printk(KERN_WARNING "%s: too small RPC reply size (%d bytes)\n", 946 clnt->cl_protname, task->tk_status); 947 rpc_exit(task, -EIO); 948 return; 949 } 950 951 req->rq_rcv_buf.len = req->rq_private_buf.len; 952 953 /* Check that the softirq receive buffer is valid */ 954 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 955 sizeof(req->rq_rcv_buf)) != 0); 956 957 /* Verify the RPC header */ 958 if (!(p = call_verify(task))) { 959 if (task->tk_action == NULL) 960 return; 961 goto out_retry; 962 } 963 964 task->tk_action = NULL; 965 966 if (decode) 967 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 968 task->tk_msg.rpc_resp); 969 dprintk("RPC: %4d call_decode result %d\n", task->tk_pid, 970 task->tk_status); 971 return; 972 out_retry: 973 req->rq_received = req->rq_private_buf.len = 0; 974 task->tk_status = 0; 975 } 976 977 /* 978 * 8. Refresh the credentials if rejected by the server 979 */ 980 static void 981 call_refresh(struct rpc_task *task) 982 { 983 dprintk("RPC: %4d call_refresh\n", task->tk_pid); 984 985 xprt_release(task); /* Must do to obtain new XID */ 986 task->tk_action = call_refreshresult; 987 task->tk_status = 0; 988 task->tk_client->cl_stats->rpcauthrefresh++; 989 rpcauth_refreshcred(task); 990 } 991 992 /* 993 * 8a. Process the results of a credential refresh 994 */ 995 static void 996 call_refreshresult(struct rpc_task *task) 997 { 998 int status = task->tk_status; 999 dprintk("RPC: %4d call_refreshresult (status %d)\n", 1000 task->tk_pid, task->tk_status); 1001 1002 task->tk_status = 0; 1003 task->tk_action = call_reserve; 1004 if (status >= 0 && rpcauth_uptodatecred(task)) 1005 return; 1006 if (status == -EACCES) { 1007 rpc_exit(task, -EACCES); 1008 return; 1009 } 1010 task->tk_action = call_refresh; 1011 if (status != -ETIMEDOUT) 1012 rpc_delay(task, 3*HZ); 1013 return; 1014 } 1015 1016 /* 1017 * Call header serialization 1018 */ 1019 static u32 * 1020 call_header(struct rpc_task *task) 1021 { 1022 struct rpc_clnt *clnt = task->tk_client; 1023 struct rpc_xprt *xprt = clnt->cl_xprt; 1024 struct rpc_rqst *req = task->tk_rqstp; 1025 u32 *p = req->rq_svec[0].iov_base; 1026 1027 /* FIXME: check buffer size? */ 1028 if (xprt->stream) 1029 *p++ = 0; /* fill in later */ 1030 *p++ = req->rq_xid; /* XID */ 1031 *p++ = htonl(RPC_CALL); /* CALL */ 1032 *p++ = htonl(RPC_VERSION); /* RPC version */ 1033 *p++ = htonl(clnt->cl_prog); /* program number */ 1034 *p++ = htonl(clnt->cl_vers); /* program version */ 1035 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 1036 p = rpcauth_marshcred(task, p); 1037 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 1038 return p; 1039 } 1040 1041 /* 1042 * Reply header verification 1043 */ 1044 static u32 * 1045 call_verify(struct rpc_task *task) 1046 { 1047 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1048 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1049 u32 *p = iov->iov_base, n; 1050 int error = -EACCES; 1051 1052 if ((len -= 3) < 0) 1053 goto out_overflow; 1054 p += 1; /* skip XID */ 1055 1056 if ((n = ntohl(*p++)) != RPC_REPLY) { 1057 printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n); 1058 goto out_retry; 1059 } 1060 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1061 if (--len < 0) 1062 goto out_overflow; 1063 switch ((n = ntohl(*p++))) { 1064 case RPC_AUTH_ERROR: 1065 break; 1066 case RPC_MISMATCH: 1067 dprintk("%s: RPC call version mismatch!\n", __FUNCTION__); 1068 error = -EPROTONOSUPPORT; 1069 goto out_err; 1070 default: 1071 dprintk("%s: RPC call rejected, unknown error: %x\n", __FUNCTION__, n); 1072 goto out_eio; 1073 } 1074 if (--len < 0) 1075 goto out_overflow; 1076 switch ((n = ntohl(*p++))) { 1077 case RPC_AUTH_REJECTEDCRED: 1078 case RPC_AUTH_REJECTEDVERF: 1079 case RPCSEC_GSS_CREDPROBLEM: 1080 case RPCSEC_GSS_CTXPROBLEM: 1081 if (!task->tk_cred_retry) 1082 break; 1083 task->tk_cred_retry--; 1084 dprintk("RPC: %4d call_verify: retry stale creds\n", 1085 task->tk_pid); 1086 rpcauth_invalcred(task); 1087 task->tk_action = call_refresh; 1088 return NULL; 1089 case RPC_AUTH_BADCRED: 1090 case RPC_AUTH_BADVERF: 1091 /* possibly garbled cred/verf? */ 1092 if (!task->tk_garb_retry) 1093 break; 1094 task->tk_garb_retry--; 1095 dprintk("RPC: %4d call_verify: retry garbled creds\n", 1096 task->tk_pid); 1097 task->tk_action = call_bind; 1098 return NULL; 1099 case RPC_AUTH_TOOWEAK: 1100 printk(KERN_NOTICE "call_verify: server requires stronger " 1101 "authentication.\n"); 1102 break; 1103 default: 1104 printk(KERN_WARNING "call_verify: unknown auth error: %x\n", n); 1105 error = -EIO; 1106 } 1107 dprintk("RPC: %4d call_verify: call rejected %d\n", 1108 task->tk_pid, n); 1109 goto out_err; 1110 } 1111 if (!(p = rpcauth_checkverf(task, p))) { 1112 printk(KERN_WARNING "call_verify: auth check failed\n"); 1113 goto out_retry; /* bad verifier, retry */ 1114 } 1115 len = p - (u32 *)iov->iov_base - 1; 1116 if (len < 0) 1117 goto out_overflow; 1118 switch ((n = ntohl(*p++))) { 1119 case RPC_SUCCESS: 1120 return p; 1121 case RPC_PROG_UNAVAIL: 1122 dprintk("RPC: call_verify: program %u is unsupported by server %s\n", 1123 (unsigned int)task->tk_client->cl_prog, 1124 task->tk_client->cl_server); 1125 error = -EPFNOSUPPORT; 1126 goto out_err; 1127 case RPC_PROG_MISMATCH: 1128 dprintk("RPC: call_verify: program %u, version %u unsupported by server %s\n", 1129 (unsigned int)task->tk_client->cl_prog, 1130 (unsigned int)task->tk_client->cl_vers, 1131 task->tk_client->cl_server); 1132 error = -EPROTONOSUPPORT; 1133 goto out_err; 1134 case RPC_PROC_UNAVAIL: 1135 dprintk("RPC: call_verify: proc %p unsupported by program %u, version %u on server %s\n", 1136 task->tk_msg.rpc_proc, 1137 task->tk_client->cl_prog, 1138 task->tk_client->cl_vers, 1139 task->tk_client->cl_server); 1140 error = -EOPNOTSUPP; 1141 goto out_err; 1142 case RPC_GARBAGE_ARGS: 1143 dprintk("RPC: %4d %s: server saw garbage\n", task->tk_pid, __FUNCTION__); 1144 break; /* retry */ 1145 default: 1146 printk(KERN_WARNING "call_verify: server accept status: %x\n", n); 1147 /* Also retry */ 1148 } 1149 1150 out_retry: 1151 task->tk_client->cl_stats->rpcgarbage++; 1152 if (task->tk_garb_retry) { 1153 task->tk_garb_retry--; 1154 dprintk("RPC %s: retrying %4d\n", __FUNCTION__, task->tk_pid); 1155 task->tk_action = call_bind; 1156 return NULL; 1157 } 1158 printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__); 1159 out_eio: 1160 error = -EIO; 1161 out_err: 1162 rpc_exit(task, error); 1163 return NULL; 1164 out_overflow: 1165 printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__); 1166 goto out_retry; 1167 } 1168 1169 static int rpcproc_encode_null(void *rqstp, u32 *data, void *obj) 1170 { 1171 return 0; 1172 } 1173 1174 static int rpcproc_decode_null(void *rqstp, u32 *data, void *obj) 1175 { 1176 return 0; 1177 } 1178 1179 static struct rpc_procinfo rpcproc_null = { 1180 .p_encode = rpcproc_encode_null, 1181 .p_decode = rpcproc_decode_null, 1182 }; 1183 1184 int rpc_ping(struct rpc_clnt *clnt, int flags) 1185 { 1186 struct rpc_message msg = { 1187 .rpc_proc = &rpcproc_null, 1188 }; 1189 int err; 1190 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1191 err = rpc_call_sync(clnt, &msg, flags); 1192 put_rpccred(msg.rpc_cred); 1193 return err; 1194 } 1195