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/types.h>
27 #include <linux/mm.h>
28 #include <linux/slab.h>
29 #include <linux/in.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_transmit(struct rpc_task *task);
56 static void call_status(struct rpc_task *task);
57 static void call_refresh(struct rpc_task *task);
58 static void call_refreshresult(struct rpc_task *task);
59 static void call_timeout(struct rpc_task *task);
60 static void call_connect(struct rpc_task *task);
61 static void call_connect_status(struct rpc_task *task);
62 static u32 * call_header(struct rpc_task *task);
63 static u32 * call_verify(struct rpc_task *task);
64
65
66 static int
67 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
68 {
69 static uint32_t clntid;
70 int error;
71
72 if (dir_name == NULL)
73 return 0;
74 for (;;) {
75 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
76 "%s/clnt%x", dir_name,
77 (unsigned int)clntid++);
78 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
79 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
80 if (!IS_ERR(clnt->cl_dentry))
81 return 0;
82 error = PTR_ERR(clnt->cl_dentry);
83 if (error != -EEXIST) {
84 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
85 clnt->cl_pathname, error);
86 return error;
87 }
88 }
89 }
90
91 /*
92 * Create an RPC client
93 * FIXME: This should also take a flags argument (as in task->tk_flags).
94 * It's called (among others) from pmap_create_client, which may in
95 * turn be called by an async task. In this case, rpciod should not be
96 * made to sleep too long.
97 */
98 struct rpc_clnt *
99 rpc_create_client(struct rpc_xprt *xprt, char *servname,
100 struct rpc_program *program, u32 vers,
101 rpc_authflavor_t flavor)
102 {
103 struct rpc_version *version;
104 struct rpc_clnt *clnt = NULL;
105 int err;
106 int len;
107
108 dprintk("RPC: creating %s client for %s (xprt %p)\n",
109 program->name, servname, xprt);
110
111 err = -EINVAL;
112 if (!xprt)
113 goto out_err;
114 if (vers >= program->nrvers || !(version = program->version[vers]))
115 goto out_err;
116
117 err = -ENOMEM;
118 clnt = (struct rpc_clnt *) kmalloc(sizeof(*clnt), GFP_KERNEL);
119 if (!clnt)
120 goto out_err;
121 memset(clnt, 0, sizeof(*clnt));
122 atomic_set(&clnt->cl_users, 0);
123 atomic_set(&clnt->cl_count, 1);
124 clnt->cl_parent = clnt;
125
126 clnt->cl_server = clnt->cl_inline_name;
127 len = strlen(servname) + 1;
128 if (len > sizeof(clnt->cl_inline_name)) {
129 char *buf = kmalloc(len, GFP_KERNEL);
130 if (buf != 0)
131 clnt->cl_server = buf;
132 else
133 len = sizeof(clnt->cl_inline_name);
134 }
135 strlcpy(clnt->cl_server, servname, len);
136
137 clnt->cl_xprt = xprt;
138 clnt->cl_procinfo = version->procs;
139 clnt->cl_maxproc = version->nrprocs;
140 clnt->cl_protname = program->name;
141 clnt->cl_pmap = &clnt->cl_pmap_default;
142 clnt->cl_port = xprt->addr.sin_port;
143 clnt->cl_prog = program->number;
144 clnt->cl_vers = version->number;
145 clnt->cl_prot = xprt->prot;
146 clnt->cl_stats = program->stats;
147 rpc_init_wait_queue(&clnt->cl_pmap_default.pm_bindwait, "bindwait");
148
149 if (!clnt->cl_port)
150 clnt->cl_autobind = 1;
151
152 clnt->cl_rtt = &clnt->cl_rtt_default;
153 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
154
155 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
156 if (err < 0)
157 goto out_no_path;
158
159 err = -ENOMEM;
160 if (!rpcauth_create(flavor, clnt)) {
161 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
162 flavor);
163 goto out_no_auth;
164 }
165
166 /* save the nodename */
167 clnt->cl_nodelen = strlen(system_utsname.nodename);
168 if (clnt->cl_nodelen > UNX_MAXNODENAME)
169 clnt->cl_nodelen = UNX_MAXNODENAME;
170 memcpy(clnt->cl_nodename, system_utsname.nodename, clnt->cl_nodelen);
171 return clnt;
172
173 out_no_auth:
174 rpc_rmdir(clnt->cl_pathname);
175 out_no_path:
176 if (clnt->cl_server != clnt->cl_inline_name)
177 kfree(clnt->cl_server);
178 kfree(clnt);
179 out_err:
180 return ERR_PTR(err);
181 }
182
183 /*
184 * This function clones the RPC client structure. It allows us to share the
185 * same transport while varying parameters such as the authentication
186 * flavour.
187 */
188 struct rpc_clnt *
189 rpc_clone_client(struct rpc_clnt *clnt)
190 {
191 struct rpc_clnt *new;
192
193 new = (struct rpc_clnt *)kmalloc(sizeof(*new), GFP_KERNEL);
194 if (!new)
195 goto out_no_clnt;
196 memcpy(new, clnt, sizeof(*new));
197 atomic_set(&new->cl_count, 1);
198 atomic_set(&new->cl_users, 0);
199 new->cl_parent = clnt;
200 atomic_inc(&clnt->cl_count);
201 /* Duplicate portmapper */
202 rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait");
203 /* Turn off autobind on clones */
204 new->cl_autobind = 0;
205 new->cl_oneshot = 0;
206 new->cl_dead = 0;
207 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
208 if (new->cl_auth)
209 atomic_inc(&new->cl_auth->au_count);
210 return new;
211 out_no_clnt:
212 printk(KERN_INFO "RPC: out of memory in %s\n", __FUNCTION__);
213 return ERR_PTR(-ENOMEM);
214 }
215
216 /*
217 * Properly shut down an RPC client, terminating all outstanding
218 * requests. Note that we must be certain that cl_oneshot and
219 * cl_dead are cleared, or else the client would be destroyed
220 * when the last task releases it.
221 */
222 int
223 rpc_shutdown_client(struct rpc_clnt *clnt)
224 {
225 dprintk("RPC: shutting down %s client for %s, tasks=%d\n",
226 clnt->cl_protname, clnt->cl_server,
227 atomic_read(&clnt->cl_users));
228
229 while (atomic_read(&clnt->cl_users) > 0) {
230 /* Don't let rpc_release_client destroy us */
231 clnt->cl_oneshot = 0;
232 clnt->cl_dead = 0;
233 rpc_killall_tasks(clnt);
234 sleep_on_timeout(&destroy_wait, 1*HZ);
235 }
236
237 if (atomic_read(&clnt->cl_users) < 0) {
238 printk(KERN_ERR "RPC: rpc_shutdown_client clnt %p tasks=%d\n",
239 clnt, atomic_read(&clnt->cl_users));
240 #ifdef RPC_DEBUG
241 rpc_show_tasks();
242 #endif
243 BUG();
244 }
245
246 return rpc_destroy_client(clnt);
247 }
248
249 /*
250 * Delete an RPC client
251 */
252 int
253 rpc_destroy_client(struct rpc_clnt *clnt)
254 {
255 if (!atomic_dec_and_test(&clnt->cl_count))
256 return 1;
257 BUG_ON(atomic_read(&clnt->cl_users) != 0);
258
259 dprintk("RPC: destroying %s client for %s\n",
260 clnt->cl_protname, clnt->cl_server);
261 if (clnt->cl_auth) {
262 rpcauth_destroy(clnt->cl_auth);
263 clnt->cl_auth = NULL;
264 }
265 if (clnt->cl_parent != clnt) {
266 rpc_destroy_client(clnt->cl_parent);
267 goto out_free;
268 }
269 if (clnt->cl_pathname[0])
270 rpc_rmdir(clnt->cl_pathname);
271 if (clnt->cl_xprt) {
272 xprt_destroy(clnt->cl_xprt);
273 clnt->cl_xprt = NULL;
274 }
275 if (clnt->cl_server != clnt->cl_inline_name)
276 kfree(clnt->cl_server);
277 out_free:
278 kfree(clnt);
279 return 0;
280 }
281
282 /*
283 * Release an RPC client
284 */
285 void
286 rpc_release_client(struct rpc_clnt *clnt)
287 {
288 dprintk("RPC: rpc_release_client(%p, %d)\n",
289 clnt, atomic_read(&clnt->cl_users));
290
291 if (!atomic_dec_and_test(&clnt->cl_users))
292 return;
293 wake_up(&destroy_wait);
294 if (clnt->cl_oneshot || clnt->cl_dead)
295 rpc_destroy_client(clnt);
296 }
297
298 /*
299 * Default callback for async RPC calls
300 */
301 static void
302 rpc_default_callback(struct rpc_task *task)
303 {
304 }
305
306 /*
307 * Export the signal mask handling for aysnchronous code that
308 * sleeps on RPC calls
309 */
310
311 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
312 {
313 unsigned long sigallow = sigmask(SIGKILL);
314 unsigned long irqflags;
315
316 /* Turn off various signals */
317 if (clnt->cl_intr) {
318 struct k_sigaction *action = current->sighand->action;
319 if (action[SIGINT-1].sa.sa_handler == SIG_DFL)
320 sigallow |= sigmask(SIGINT);
321 if (action[SIGQUIT-1].sa.sa_handler == SIG_DFL)
322 sigallow |= sigmask(SIGQUIT);
323 }
324 spin_lock_irqsave(¤t->sighand->siglock, irqflags);
325 *oldset = current->blocked;
326 siginitsetinv(¤t->blocked, sigallow & ~oldset->sig[0]);
327 recalc_sigpending();
328 spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
329 }
330
331 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
332 {
333 unsigned long irqflags;
334
335 spin_lock_irqsave(¤t->sighand->siglock, irqflags);
336 current->blocked = *oldset;
337 recalc_sigpending();
338 spin_unlock_irqrestore(¤t->sighand->siglock, irqflags);
339 }
340
341 /*
342 * New rpc_call implementation
343 */
344 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
345 {
346 struct rpc_task *task;
347 sigset_t oldset;
348 int status;
349
350 /* If this client is slain all further I/O fails */
351 if (clnt->cl_dead)
352 return -EIO;
353
354 BUG_ON(flags & RPC_TASK_ASYNC);
355
356 rpc_clnt_sigmask(clnt, &oldset);
357
358 status = -ENOMEM;
359 task = rpc_new_task(clnt, NULL, flags);
360 if (task == NULL)
361 goto out;
362
363 rpc_call_setup(task, msg, 0);
364
365 /* Set up the call info struct and execute the task */
366 if (task->tk_status == 0)
367 status = rpc_execute(task);
368 else {
369 status = task->tk_status;
370 rpc_release_task(task);
371 }
372
373 out:
374 rpc_clnt_sigunmask(clnt, &oldset);
375
376 return status;
377 }
378
379 /*
380 * New rpc_call implementation
381 */
382 int
383 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
384 rpc_action callback, void *data)
385 {
386 struct rpc_task *task;
387 sigset_t oldset;
388 int status;
389
390 /* If this client is slain all further I/O fails */
391 if (clnt->cl_dead)
392 return -EIO;
393
394 flags |= RPC_TASK_ASYNC;
395
396 rpc_clnt_sigmask(clnt, &oldset);
397
398 /* Create/initialize a new RPC task */
399 if (!callback)
400 callback = rpc_default_callback;
401 status = -ENOMEM;
402 if (!(task = rpc_new_task(clnt, callback, flags)))
403 goto out;
404 task->tk_calldata = data;
405
406 rpc_call_setup(task, msg, 0);
407
408 /* Set up the call info struct and execute the task */
409 if (task->tk_status == 0)
410 status = rpc_execute(task);
411 else {
412 status = task->tk_status;
413 rpc_release_task(task);
414 }
415
416 out:
417 rpc_clnt_sigunmask(clnt, &oldset);
418
419 return status;
420 }
421
422
423 void
424 rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
425 {
426 task->tk_msg = *msg;
427 task->tk_flags |= flags;
428 /* Bind the user cred */
429 if (task->tk_msg.rpc_cred != NULL) {
430 rpcauth_holdcred(task);
431 } else
432 rpcauth_bindcred(task);
433
434 if (task->tk_status == 0)
435 task->tk_action = call_start;
436 else
437 task->tk_action = NULL;
438 }
439
440 void
441 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
442 {
443 struct rpc_xprt *xprt = clnt->cl_xprt;
444
445 xprt->sndsize = 0;
446 if (sndsize)
447 xprt->sndsize = sndsize + RPC_SLACK_SPACE;
448 xprt->rcvsize = 0;
449 if (rcvsize)
450 xprt->rcvsize = rcvsize + RPC_SLACK_SPACE;
451 if (xprt_connected(xprt))
452 xprt_sock_setbufsize(xprt);
453 }
454
455 /*
456 * Restart an (async) RPC call. Usually called from within the
457 * exit handler.
458 */
459 void
460 rpc_restart_call(struct rpc_task *task)
461 {
462 if (RPC_ASSASSINATED(task))
463 return;
464
465 task->tk_action = call_start;
466 }
467
468 /*
469 * 0. Initial state
470 *
471 * Other FSM states can be visited zero or more times, but
472 * this state is visited exactly once for each RPC.
473 */
474 static void
475 call_start(struct rpc_task *task)
476 {
477 struct rpc_clnt *clnt = task->tk_client;
478
479 dprintk("RPC: %4d call_start %s%d proc %d (%s)\n", task->tk_pid,
480 clnt->cl_protname, clnt->cl_vers, task->tk_msg.rpc_proc->p_proc,
481 (RPC_IS_ASYNC(task) ? "async" : "sync"));
482
483 /* Increment call count */
484 task->tk_msg.rpc_proc->p_count++;
485 clnt->cl_stats->rpccnt++;
486 task->tk_action = call_reserve;
487 }
488
489 /*
490 * 1. Reserve an RPC call slot
491 */
492 static void
493 call_reserve(struct rpc_task *task)
494 {
495 dprintk("RPC: %4d call_reserve\n", task->tk_pid);
496
497 if (!rpcauth_uptodatecred(task)) {
498 task->tk_action = call_refresh;
499 return;
500 }
501
502 task->tk_status = 0;
503 task->tk_action = call_reserveresult;
504 xprt_reserve(task);
505 }
506
507 /*
508 * 1b. Grok the result of xprt_reserve()
509 */
510 static void
511 call_reserveresult(struct rpc_task *task)
512 {
513 int status = task->tk_status;
514
515 dprintk("RPC: %4d call_reserveresult (status %d)\n",
516 task->tk_pid, task->tk_status);
517
518 /*
519 * After a call to xprt_reserve(), we must have either
520 * a request slot or else an error status.
521 */
522 task->tk_status = 0;
523 if (status >= 0) {
524 if (task->tk_rqstp) {
525 task->tk_action = call_allocate;
526 return;
527 }
528
529 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
530 __FUNCTION__, status);
531 rpc_exit(task, -EIO);
532 return;
533 }
534
535 /*
536 * Even though there was an error, we may have acquired
537 * a request slot somehow. Make sure not to leak it.
538 */
539 if (task->tk_rqstp) {
540 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
541 __FUNCTION__, status);
542 xprt_release(task);
543 }
544
545 switch (status) {
546 case -EAGAIN: /* woken up; retry */
547 task->tk_action = call_reserve;
548 return;
549 case -EIO: /* probably a shutdown */
550 break;
551 default:
552 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
553 __FUNCTION__, status);
554 break;
555 }
556 rpc_exit(task, status);
557 }
558
559 /*
560 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
561 * (Note: buffer memory is freed in rpc_task_release).
562 */
563 static void
564 call_allocate(struct rpc_task *task)
565 {
566 unsigned int bufsiz;
567
568 dprintk("RPC: %4d call_allocate (status %d)\n",
569 task->tk_pid, task->tk_status);
570 task->tk_action = call_bind;
571 if (task->tk_buffer)
572 return;
573
574 /* FIXME: compute buffer requirements more exactly using
575 * auth->au_wslack */
576 bufsiz = task->tk_msg.rpc_proc->p_bufsiz + RPC_SLACK_SPACE;
577
578 if (rpc_malloc(task, bufsiz << 1) != NULL)
579 return;
580 printk(KERN_INFO "RPC: buffer allocation failed for task %p\n", task);
581
582 if (RPC_IS_ASYNC(task) || !(task->tk_client->cl_intr && signalled())) {
583 xprt_release(task);
584 task->tk_action = call_reserve;
585 rpc_delay(task, HZ>>4);
586 return;
587 }
588
589 rpc_exit(task, -ERESTARTSYS);
590 }
591
592 /*
593 * 3. Encode arguments of an RPC call
594 */
595 static void
596 call_encode(struct rpc_task *task)
597 {
598 struct rpc_clnt *clnt = task->tk_client;
599 struct rpc_rqst *req = task->tk_rqstp;
600 struct xdr_buf *sndbuf = &req->rq_snd_buf;
601 struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
602 unsigned int bufsiz;
603 kxdrproc_t encode;
604 int status;
605 u32 *p;
606
607 dprintk("RPC: %4d call_encode (status %d)\n",
608 task->tk_pid, task->tk_status);
609
610 /* Default buffer setup */
611 bufsiz = task->tk_bufsize >> 1;
612 sndbuf->head[0].iov_base = (void *)task->tk_buffer;
613 sndbuf->head[0].iov_len = bufsiz;
614 sndbuf->tail[0].iov_len = 0;
615 sndbuf->page_len = 0;
616 sndbuf->len = 0;
617 sndbuf->buflen = bufsiz;
618 rcvbuf->head[0].iov_base = (void *)((char *)task->tk_buffer + bufsiz);
619 rcvbuf->head[0].iov_len = bufsiz;
620 rcvbuf->tail[0].iov_len = 0;
621 rcvbuf->page_len = 0;
622 rcvbuf->len = 0;
623 rcvbuf->buflen = bufsiz;
624
625 /* Encode header and provided arguments */
626 encode = task->tk_msg.rpc_proc->p_encode;
627 if (!(p = call_header(task))) {
628 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
629 rpc_exit(task, -EIO);
630 return;
631 }
632 if (encode && (status = rpcauth_wrap_req(task, encode, req, p,
633 task->tk_msg.rpc_argp)) < 0) {
634 printk(KERN_WARNING "%s: can't encode arguments: %d\n",
635 clnt->cl_protname, -status);
636 rpc_exit(task, status);
637 }
638 }
639
640 /*
641 * 4. Get the server port number if not yet set
642 */
643 static void
644 call_bind(struct rpc_task *task)
645 {
646 struct rpc_clnt *clnt = task->tk_client;
647 struct rpc_xprt *xprt = clnt->cl_xprt;
648
649 dprintk("RPC: %4d call_bind xprt %p %s connected\n", task->tk_pid,
650 xprt, (xprt_connected(xprt) ? "is" : "is not"));
651
652 task->tk_action = (xprt_connected(xprt)) ? call_transmit : call_connect;
653
654 if (!clnt->cl_port) {
655 task->tk_action = call_connect;
656 task->tk_timeout = RPC_CONNECT_TIMEOUT;
657 rpc_getport(task, clnt);
658 }
659 }
660
661 /*
662 * 4a. Connect to the RPC server (TCP case)
663 */
664 static void
665 call_connect(struct rpc_task *task)
666 {
667 struct rpc_clnt *clnt = task->tk_client;
668
669 dprintk("RPC: %4d call_connect status %d\n",
670 task->tk_pid, task->tk_status);
671
672 if (xprt_connected(clnt->cl_xprt)) {
673 task->tk_action = call_transmit;
674 return;
675 }
676 task->tk_action = call_connect_status;
677 if (task->tk_status < 0)
678 return;
679 xprt_connect(task);
680 }
681
682 /*
683 * 4b. Sort out connect result
684 */
685 static void
686 call_connect_status(struct rpc_task *task)
687 {
688 struct rpc_clnt *clnt = task->tk_client;
689 int status = task->tk_status;
690
691 task->tk_status = 0;
692 if (status >= 0) {
693 clnt->cl_stats->netreconn++;
694 task->tk_action = call_transmit;
695 return;
696 }
697
698 /* Something failed: we may have to rebind */
699 if (clnt->cl_autobind)
700 clnt->cl_port = 0;
701 switch (status) {
702 case -ENOTCONN:
703 case -ETIMEDOUT:
704 case -EAGAIN:
705 task->tk_action = (clnt->cl_port == 0) ? call_bind : call_connect;
706 break;
707 default:
708 rpc_exit(task, -EIO);
709 }
710 }
711
712 /*
713 * 5. Transmit the RPC request, and wait for reply
714 */
715 static void
716 call_transmit(struct rpc_task *task)
717 {
718 dprintk("RPC: %4d call_transmit (status %d)\n",
719 task->tk_pid, task->tk_status);
720
721 task->tk_action = call_status;
722 if (task->tk_status < 0)
723 return;
724 task->tk_status = xprt_prepare_transmit(task);
725 if (task->tk_status != 0)
726 return;
727 /* Encode here so that rpcsec_gss can use correct sequence number. */
728 if (!task->tk_rqstp->rq_bytes_sent)
729 call_encode(task);
730 if (task->tk_status < 0)
731 return;
732 xprt_transmit(task);
733 if (task->tk_status < 0)
734 return;
735 if (!task->tk_msg.rpc_proc->p_decode) {
736 task->tk_action = NULL;
737 rpc_wake_up_task(task);
738 }
739 }
740
741 /*
742 * 6. Sort out the RPC call status
743 */
744 static void
745 call_status(struct rpc_task *task)
746 {
747 struct rpc_clnt *clnt = task->tk_client;
748 struct rpc_rqst *req = task->tk_rqstp;
749 int status;
750
751 if (req->rq_received > 0 && !req->rq_bytes_sent)
752 task->tk_status = req->rq_received;
753
754 dprintk("RPC: %4d call_status (status %d)\n",
755 task->tk_pid, task->tk_status);
756
757 status = task->tk_status;
758 if (status >= 0) {
759 task->tk_action = call_decode;
760 return;
761 }
762
763 task->tk_status = 0;
764 switch(status) {
765 case -ETIMEDOUT:
766 task->tk_action = call_timeout;
767 break;
768 case -ECONNREFUSED:
769 case -ENOTCONN:
770 req->rq_bytes_sent = 0;
771 if (clnt->cl_autobind)
772 clnt->cl_port = 0;
773 task->tk_action = call_bind;
774 break;
775 case -EAGAIN:
776 task->tk_action = call_transmit;
777 break;
778 case -EIO:
779 /* shutdown or soft timeout */
780 rpc_exit(task, status);
781 break;
782 default:
783 if (clnt->cl_chatty)
784 printk("%s: RPC call returned error %d\n",
785 clnt->cl_protname, -status);
786 rpc_exit(task, status);
787 break;
788 }
789 }
790
791 /*
792 * 6a. Handle RPC timeout
793 * We do not release the request slot, so we keep using the
794 * same XID for all retransmits.
795 */
796 static void
797 call_timeout(struct rpc_task *task)
798 {
799 struct rpc_clnt *clnt = task->tk_client;
800
801 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
802 dprintk("RPC: %4d call_timeout (minor)\n", task->tk_pid);
803 goto retry;
804 }
805
806 dprintk("RPC: %4d call_timeout (major)\n", task->tk_pid);
807 if (RPC_IS_SOFT(task)) {
808 if (clnt->cl_chatty)
809 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
810 clnt->cl_protname, clnt->cl_server);
811 rpc_exit(task, -EIO);
812 return;
813 }
814
815 if (clnt->cl_chatty && !(task->tk_flags & RPC_CALL_MAJORSEEN)) {
816 task->tk_flags |= RPC_CALL_MAJORSEEN;
817 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
818 clnt->cl_protname, clnt->cl_server);
819 }
820 if (clnt->cl_autobind)
821 clnt->cl_port = 0;
822
823 retry:
824 clnt->cl_stats->rpcretrans++;
825 task->tk_action = call_bind;
826 task->tk_status = 0;
827 }
828
829 /*
830 * 7. Decode the RPC reply
831 */
832 static void
833 call_decode(struct rpc_task *task)
834 {
835 struct rpc_clnt *clnt = task->tk_client;
836 struct rpc_rqst *req = task->tk_rqstp;
837 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
838 u32 *p;
839
840 dprintk("RPC: %4d call_decode (status %d)\n",
841 task->tk_pid, task->tk_status);
842
843 if (clnt->cl_chatty && (task->tk_flags & RPC_CALL_MAJORSEEN)) {
844 printk(KERN_NOTICE "%s: server %s OK\n",
845 clnt->cl_protname, clnt->cl_server);
846 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
847 }
848
849 if (task->tk_status < 12) {
850 if (!RPC_IS_SOFT(task)) {
851 task->tk_action = call_bind;
852 clnt->cl_stats->rpcretrans++;
853 goto out_retry;
854 }
855 printk(KERN_WARNING "%s: too small RPC reply size (%d bytes)\n",
856 clnt->cl_protname, task->tk_status);
857 rpc_exit(task, -EIO);
858 return;
859 }
860
861 req->rq_rcv_buf.len = req->rq_private_buf.len;
862
863 /* Check that the softirq receive buffer is valid */
864 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
865 sizeof(req->rq_rcv_buf)) != 0);
866
867 /* Verify the RPC header */
868 if (!(p = call_verify(task))) {
869 if (task->tk_action == NULL)
870 return;
871 goto out_retry;
872 }
873
874 /*
875 * The following is an NFS-specific hack to cater for setuid
876 * processes whose uid is mapped to nobody on the server.
877 */
878 if (task->tk_client->cl_droppriv &&
879 (ntohl(*p) == NFSERR_ACCES || ntohl(*p) == NFSERR_PERM)) {
880 if (RPC_IS_SETUID(task) && task->tk_suid_retry) {
881 dprintk("RPC: %4d retry squashed uid\n", task->tk_pid);
882 task->tk_flags ^= RPC_CALL_REALUID;
883 task->tk_action = call_bind;
884 task->tk_suid_retry--;
885 goto out_retry;
886 }
887 }
888
889 task->tk_action = NULL;
890
891 if (decode)
892 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
893 task->tk_msg.rpc_resp);
894 dprintk("RPC: %4d call_decode result %d\n", task->tk_pid,
895 task->tk_status);
896 return;
897 out_retry:
898 req->rq_received = req->rq_private_buf.len = 0;
899 task->tk_status = 0;
900 }
901
902 /*
903 * 8. Refresh the credentials if rejected by the server
904 */
905 static void
906 call_refresh(struct rpc_task *task)
907 {
908 dprintk("RPC: %4d call_refresh\n", task->tk_pid);
909
910 xprt_release(task); /* Must do to obtain new XID */
911 task->tk_action = call_refreshresult;
912 task->tk_status = 0;
913 task->tk_client->cl_stats->rpcauthrefresh++;
914 rpcauth_refreshcred(task);
915 }
916
917 /*
918 * 8a. Process the results of a credential refresh
919 */
920 static void
921 call_refreshresult(struct rpc_task *task)
922 {
923 int status = task->tk_status;
924 dprintk("RPC: %4d call_refreshresult (status %d)\n",
925 task->tk_pid, task->tk_status);
926
927 task->tk_status = 0;
928 task->tk_action = call_reserve;
929 if (status >= 0 && rpcauth_uptodatecred(task))
930 return;
931 if (status == -EACCES) {
932 rpc_exit(task, -EACCES);
933 return;
934 }
935 task->tk_action = call_refresh;
936 if (status != -ETIMEDOUT)
937 rpc_delay(task, 3*HZ);
938 return;
939 }
940
941 /*
942 * Call header serialization
943 */
944 static u32 *
945 call_header(struct rpc_task *task)
946 {
947 struct rpc_clnt *clnt = task->tk_client;
948 struct rpc_xprt *xprt = clnt->cl_xprt;
949 struct rpc_rqst *req = task->tk_rqstp;
950 u32 *p = req->rq_svec[0].iov_base;
951
952 /* FIXME: check buffer size? */
953 if (xprt->stream)
954 *p++ = 0; /* fill in later */
955 *p++ = req->rq_xid; /* XID */
956 *p++ = htonl(RPC_CALL); /* CALL */
957 *p++ = htonl(RPC_VERSION); /* RPC version */
958 *p++ = htonl(clnt->cl_prog); /* program number */
959 *p++ = htonl(clnt->cl_vers); /* program version */
960 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
961 return rpcauth_marshcred(task, p);
962 }
963
964 /*
965 * Reply header verification
966 */
967 static u32 *
968 call_verify(struct rpc_task *task)
969 {
970 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
971 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
972 u32 *p = iov->iov_base, n;
973 int error = -EACCES;
974
975 if ((len -= 3) < 0)
976 goto out_overflow;
977 p += 1; /* skip XID */
978
979 if ((n = ntohl(*p++)) != RPC_REPLY) {
980 printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n);
981 goto out_retry;
982 }
983 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
984 if (--len < 0)
985 goto out_overflow;
986 switch ((n = ntohl(*p++))) {
987 case RPC_AUTH_ERROR:
988 break;
989 case RPC_MISMATCH:
990 printk(KERN_WARNING "%s: RPC call version mismatch!\n", __FUNCTION__);
991 goto out_eio;
992 default:
993 printk(KERN_WARNING "%s: RPC call rejected, unknown error: %x\n", __FUNCTION__, n);
994 goto out_eio;
995 }
996 if (--len < 0)
997 goto out_overflow;
998 switch ((n = ntohl(*p++))) {
999 case RPC_AUTH_REJECTEDCRED:
1000 case RPC_AUTH_REJECTEDVERF:
1001 case RPCSEC_GSS_CREDPROBLEM:
1002 case RPCSEC_GSS_CTXPROBLEM:
1003 if (!task->tk_cred_retry)
1004 break;
1005 task->tk_cred_retry--;
1006 dprintk("RPC: %4d call_verify: retry stale creds\n",
1007 task->tk_pid);
1008 rpcauth_invalcred(task);
1009 task->tk_action = call_refresh;
1010 return NULL;
1011 case RPC_AUTH_BADCRED:
1012 case RPC_AUTH_BADVERF:
1013 /* possibly garbled cred/verf? */
1014 if (!task->tk_garb_retry)
1015 break;
1016 task->tk_garb_retry--;
1017 dprintk("RPC: %4d call_verify: retry garbled creds\n",
1018 task->tk_pid);
1019 task->tk_action = call_bind;
1020 return NULL;
1021 case RPC_AUTH_TOOWEAK:
1022 printk(KERN_NOTICE "call_verify: server requires stronger "
1023 "authentication.\n");
1024 break;
1025 default:
1026 printk(KERN_WARNING "call_verify: unknown auth error: %x\n", n);
1027 error = -EIO;
1028 }
1029 dprintk("RPC: %4d call_verify: call rejected %d\n",
1030 task->tk_pid, n);
1031 goto out_err;
1032 }
1033 if (!(p = rpcauth_checkverf(task, p))) {
1034 printk(KERN_WARNING "call_verify: auth check failed\n");
1035 goto out_retry; /* bad verifier, retry */
1036 }
1037 len = p - (u32 *)iov->iov_base - 1;
1038 if (len < 0)
1039 goto out_overflow;
1040 switch ((n = ntohl(*p++))) {
1041 case RPC_SUCCESS:
1042 return p;
1043 case RPC_PROG_UNAVAIL:
1044 printk(KERN_WARNING "RPC: call_verify: program %u is unsupported by server %s\n",
1045 (unsigned int)task->tk_client->cl_prog,
1046 task->tk_client->cl_server);
1047 goto out_eio;
1048 case RPC_PROG_MISMATCH:
1049 printk(KERN_WARNING "RPC: call_verify: program %u, version %u unsupported by server %s\n",
1050 (unsigned int)task->tk_client->cl_prog,
1051 (unsigned int)task->tk_client->cl_vers,
1052 task->tk_client->cl_server);
1053 goto out_eio;
1054 case RPC_PROC_UNAVAIL:
1055 printk(KERN_WARNING "RPC: call_verify: proc %p unsupported by program %u, version %u on server %s\n",
1056 task->tk_msg.rpc_proc,
1057 task->tk_client->cl_prog,
1058 task->tk_client->cl_vers,
1059 task->tk_client->cl_server);
1060 goto out_eio;
1061 case RPC_GARBAGE_ARGS:
1062 dprintk("RPC: %4d %s: server saw garbage\n", task->tk_pid, __FUNCTION__);
1063 break; /* retry */
1064 default:
1065 printk(KERN_WARNING "call_verify: server accept status: %x\n", n);
1066 /* Also retry */
1067 }
1068
1069 out_retry:
1070 task->tk_client->cl_stats->rpcgarbage++;
1071 if (task->tk_garb_retry) {
1072 task->tk_garb_retry--;
1073 dprintk(KERN_WARNING "RPC %s: retrying %4d\n", __FUNCTION__, task->tk_pid);
1074 task->tk_action = call_bind;
1075 return NULL;
1076 }
1077 printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__);
1078 out_eio:
1079 error = -EIO;
1080 out_err:
1081 rpc_exit(task, error);
1082 return NULL;
1083 out_overflow:
1084 printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__);
1085 goto out_retry;
1086 }
1087
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