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v5.14.15
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * linux/fs/lockd/svc4proc.c
  4 *
  5 * Lockd server procedures. We don't implement the NLM_*_RES 
  6 * procedures because we don't use the async procedures.
  7 *
  8 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
  9 */
 10
 11#include <linux/types.h>
 12#include <linux/time.h>
 13#include <linux/lockd/lockd.h>
 14#include <linux/lockd/share.h>
 15#include <linux/sunrpc/svc_xprt.h>
 16
 17#define NLMDBG_FACILITY		NLMDBG_CLIENT
 18
 19/*
 20 * Obtain client and file from arguments
 21 */
 22static __be32
 23nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
 24			struct nlm_host **hostp, struct nlm_file **filp)
 25{
 26	struct nlm_host		*host = NULL;
 27	struct nlm_file		*file = NULL;
 28	struct nlm_lock		*lock = &argp->lock;
 29	__be32			error = 0;
 30
 31	/* nfsd callbacks must have been installed for this procedure */
 32	if (!nlmsvc_ops)
 33		return nlm_lck_denied_nolocks;
 34
 35	/* Obtain host handle */
 36	if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
 37	 || (argp->monitor && nsm_monitor(host) < 0))
 38		goto no_locks;
 39	*hostp = host;
 40
 41	/* Obtain file pointer. Not used by FREE_ALL call. */
 42	if (filp != NULL) {
 43		if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
 44			goto no_locks;
 45		*filp = file;
 46
 47		/* Set up the missing parts of the file_lock structure */
 48		lock->fl.fl_file  = file->f_file;
 49		lock->fl.fl_pid = current->tgid;
 50		lock->fl.fl_lmops = &nlmsvc_lock_operations;
 51		nlmsvc_locks_init_private(&lock->fl, host, (pid_t)lock->svid);
 52		if (!lock->fl.fl_owner) {
 53			/* lockowner allocation has failed */
 54			nlmsvc_release_host(host);
 55			return nlm_lck_denied_nolocks;
 56		}
 57	}
 58
 59	return 0;
 60
 61no_locks:
 62	nlmsvc_release_host(host);
 63 	if (error)
 64		return error;	
 65	return nlm_lck_denied_nolocks;
 66}
 67
 68/*
 69 * NULL: Test for presence of service
 70 */
 71static __be32
 72nlm4svc_proc_null(struct svc_rqst *rqstp)
 73{
 74	dprintk("lockd: NULL          called\n");
 75	return rpc_success;
 76}
 77
 78/*
 79 * TEST: Check for conflicting lock
 80 */
 81static __be32
 82__nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_res *resp)
 83{
 84	struct nlm_args *argp = rqstp->rq_argp;
 85	struct nlm_host	*host;
 86	struct nlm_file	*file;
 87	__be32 rc = rpc_success;
 88
 89	dprintk("lockd: TEST4        called\n");
 90	resp->cookie = argp->cookie;
 91
 92	/* Obtain client and file */
 93	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 94		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 95
 96	/* Now check for conflicting locks */
 97	resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
 98	if (resp->status == nlm_drop_reply)
 99		rc = rpc_drop_reply;
100	else
101		dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
102
103	nlmsvc_release_lockowner(&argp->lock);
104	nlmsvc_release_host(host);
105	nlm_release_file(file);
106	return rc;
107}
108
109static __be32
110nlm4svc_proc_test(struct svc_rqst *rqstp)
111{
112	return __nlm4svc_proc_test(rqstp, rqstp->rq_resp);
113}
114
115static __be32
116__nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_res *resp)
117{
118	struct nlm_args *argp = rqstp->rq_argp;
119	struct nlm_host	*host;
120	struct nlm_file	*file;
121	__be32 rc = rpc_success;
122
123	dprintk("lockd: LOCK          called\n");
124
125	resp->cookie = argp->cookie;
126
127	/* Obtain client and file */
128	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
129		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
130
131#if 0
132	/* If supplied state doesn't match current state, we assume it's
133	 * an old request that time-warped somehow. Any error return would
134	 * do in this case because it's irrelevant anyway.
135	 *
136	 * NB: We don't retrieve the remote host's state yet.
137	 */
138	if (host->h_nsmstate && host->h_nsmstate != argp->state) {
139		resp->status = nlm_lck_denied_nolocks;
140	} else
141#endif
142
143	/* Now try to lock the file */
144	resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
145					argp->block, &argp->cookie,
146					argp->reclaim);
147	if (resp->status == nlm_drop_reply)
148		rc = rpc_drop_reply;
149	else
150		dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
151
152	nlmsvc_release_lockowner(&argp->lock);
153	nlmsvc_release_host(host);
154	nlm_release_file(file);
155	return rc;
156}
157
158static __be32
159nlm4svc_proc_lock(struct svc_rqst *rqstp)
160{
161	return __nlm4svc_proc_lock(rqstp, rqstp->rq_resp);
162}
163
164static __be32
165__nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_res *resp)
166{
167	struct nlm_args *argp = rqstp->rq_argp;
168	struct nlm_host	*host;
169	struct nlm_file	*file;
170
171	dprintk("lockd: CANCEL        called\n");
172
173	resp->cookie = argp->cookie;
174
175	/* Don't accept requests during grace period */
176	if (locks_in_grace(SVC_NET(rqstp))) {
177		resp->status = nlm_lck_denied_grace_period;
178		return rpc_success;
179	}
180
181	/* Obtain client and file */
182	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
183		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
184
185	/* Try to cancel request. */
186	resp->status = nlmsvc_cancel_blocked(SVC_NET(rqstp), file, &argp->lock);
187
188	dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
189	nlmsvc_release_lockowner(&argp->lock);
190	nlmsvc_release_host(host);
191	nlm_release_file(file);
192	return rpc_success;
193}
194
195static __be32
196nlm4svc_proc_cancel(struct svc_rqst *rqstp)
197{
198	return __nlm4svc_proc_cancel(rqstp, rqstp->rq_resp);
199}
200
201/*
202 * UNLOCK: release a lock
203 */
204static __be32
205__nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_res *resp)
206{
207	struct nlm_args *argp = rqstp->rq_argp;
208	struct nlm_host	*host;
209	struct nlm_file	*file;
210
211	dprintk("lockd: UNLOCK        called\n");
212
213	resp->cookie = argp->cookie;
214
215	/* Don't accept new lock requests during grace period */
216	if (locks_in_grace(SVC_NET(rqstp))) {
217		resp->status = nlm_lck_denied_grace_period;
218		return rpc_success;
219	}
220
221	/* Obtain client and file */
222	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
223		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
224
225	/* Now try to remove the lock */
226	resp->status = nlmsvc_unlock(SVC_NET(rqstp), file, &argp->lock);
227
228	dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
229	nlmsvc_release_lockowner(&argp->lock);
230	nlmsvc_release_host(host);
231	nlm_release_file(file);
232	return rpc_success;
233}
234
235static __be32
236nlm4svc_proc_unlock(struct svc_rqst *rqstp)
237{
238	return __nlm4svc_proc_unlock(rqstp, rqstp->rq_resp);
239}
240
241/*
242 * GRANTED: A server calls us to tell that a process' lock request
243 * was granted
244 */
245static __be32
246__nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_res *resp)
247{
248	struct nlm_args *argp = rqstp->rq_argp;
249
250	resp->cookie = argp->cookie;
251
252	dprintk("lockd: GRANTED       called\n");
253	resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
254	dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
255	return rpc_success;
256}
257
258static __be32
259nlm4svc_proc_granted(struct svc_rqst *rqstp)
260{
261	return __nlm4svc_proc_granted(rqstp, rqstp->rq_resp);
262}
263
264/*
265 * This is the generic lockd callback for async RPC calls
266 */
267static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
268{
269	dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
270			-task->tk_status);
271}
272
273static void nlm4svc_callback_release(void *data)
274{
275	nlmsvc_release_call(data);
276}
277
278static const struct rpc_call_ops nlm4svc_callback_ops = {
279	.rpc_call_done = nlm4svc_callback_exit,
280	.rpc_release = nlm4svc_callback_release,
281};
282
283/*
284 * `Async' versions of the above service routines. They aren't really,
285 * because we send the callback before the reply proper. I hope this
286 * doesn't break any clients.
287 */
288static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc,
289		__be32 (*func)(struct svc_rqst *,  struct nlm_res *))
290{
291	struct nlm_args *argp = rqstp->rq_argp;
292	struct nlm_host	*host;
293	struct nlm_rqst	*call;
294	__be32 stat;
295
296	host = nlmsvc_lookup_host(rqstp,
297				  argp->lock.caller,
298				  argp->lock.len);
299	if (host == NULL)
300		return rpc_system_err;
301
302	call = nlm_alloc_call(host);
303	nlmsvc_release_host(host);
304	if (call == NULL)
305		return rpc_system_err;
306
307	stat = func(rqstp, &call->a_res);
308	if (stat != 0) {
309		nlmsvc_release_call(call);
310		return stat;
311	}
312
313	call->a_flags = RPC_TASK_ASYNC;
314	if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
315		return rpc_system_err;
316	return rpc_success;
317}
318
319static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp)
320{
321	dprintk("lockd: TEST_MSG      called\n");
322	return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, __nlm4svc_proc_test);
323}
324
325static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp)
326{
327	dprintk("lockd: LOCK_MSG      called\n");
328	return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, __nlm4svc_proc_lock);
329}
330
331static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp)
332{
333	dprintk("lockd: CANCEL_MSG    called\n");
334	return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, __nlm4svc_proc_cancel);
335}
336
337static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp)
338{
339	dprintk("lockd: UNLOCK_MSG    called\n");
340	return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, __nlm4svc_proc_unlock);
341}
342
343static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp)
344{
345	dprintk("lockd: GRANTED_MSG   called\n");
346	return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, __nlm4svc_proc_granted);
347}
348
349/*
350 * SHARE: create a DOS share or alter existing share.
351 */
352static __be32
353nlm4svc_proc_share(struct svc_rqst *rqstp)
354{
355	struct nlm_args *argp = rqstp->rq_argp;
356	struct nlm_res *resp = rqstp->rq_resp;
357	struct nlm_host	*host;
358	struct nlm_file	*file;
359
360	dprintk("lockd: SHARE         called\n");
361
362	resp->cookie = argp->cookie;
363
364	/* Don't accept new lock requests during grace period */
365	if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
366		resp->status = nlm_lck_denied_grace_period;
367		return rpc_success;
368	}
369
370	/* Obtain client and file */
371	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
372		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
373
374	/* Now try to create the share */
375	resp->status = nlmsvc_share_file(host, file, argp);
376
377	dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
378	nlmsvc_release_lockowner(&argp->lock);
379	nlmsvc_release_host(host);
380	nlm_release_file(file);
381	return rpc_success;
382}
383
384/*
385 * UNSHARE: Release a DOS share.
386 */
387static __be32
388nlm4svc_proc_unshare(struct svc_rqst *rqstp)
389{
390	struct nlm_args *argp = rqstp->rq_argp;
391	struct nlm_res *resp = rqstp->rq_resp;
392	struct nlm_host	*host;
393	struct nlm_file	*file;
394
395	dprintk("lockd: UNSHARE       called\n");
396
397	resp->cookie = argp->cookie;
398
399	/* Don't accept requests during grace period */
400	if (locks_in_grace(SVC_NET(rqstp))) {
401		resp->status = nlm_lck_denied_grace_period;
402		return rpc_success;
403	}
404
405	/* Obtain client and file */
406	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
407		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
408
409	/* Now try to lock the file */
410	resp->status = nlmsvc_unshare_file(host, file, argp);
411
412	dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
413	nlmsvc_release_lockowner(&argp->lock);
414	nlmsvc_release_host(host);
415	nlm_release_file(file);
416	return rpc_success;
417}
418
419/*
420 * NM_LOCK: Create an unmonitored lock
421 */
422static __be32
423nlm4svc_proc_nm_lock(struct svc_rqst *rqstp)
424{
425	struct nlm_args *argp = rqstp->rq_argp;
426
427	dprintk("lockd: NM_LOCK       called\n");
428
429	argp->monitor = 0;		/* just clean the monitor flag */
430	return nlm4svc_proc_lock(rqstp);
431}
432
433/*
434 * FREE_ALL: Release all locks and shares held by client
435 */
436static __be32
437nlm4svc_proc_free_all(struct svc_rqst *rqstp)
438{
439	struct nlm_args *argp = rqstp->rq_argp;
440	struct nlm_host	*host;
441
442	/* Obtain client */
443	if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
444		return rpc_success;
445
446	nlmsvc_free_host_resources(host);
447	nlmsvc_release_host(host);
448	return rpc_success;
449}
450
451/*
452 * SM_NOTIFY: private callback from statd (not part of official NLM proto)
453 */
454static __be32
455nlm4svc_proc_sm_notify(struct svc_rqst *rqstp)
456{
457	struct nlm_reboot *argp = rqstp->rq_argp;
458
459	dprintk("lockd: SM_NOTIFY     called\n");
460
461	if (!nlm_privileged_requester(rqstp)) {
462		char buf[RPC_MAX_ADDRBUFLEN];
463		printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
464				svc_print_addr(rqstp, buf, sizeof(buf)));
465		return rpc_system_err;
466	}
467
468	nlm_host_rebooted(SVC_NET(rqstp), argp);
469	return rpc_success;
470}
471
472/*
473 * client sent a GRANTED_RES, let's remove the associated block
474 */
475static __be32
476nlm4svc_proc_granted_res(struct svc_rqst *rqstp)
477{
478	struct nlm_res *argp = rqstp->rq_argp;
479
480        if (!nlmsvc_ops)
481                return rpc_success;
482
483        dprintk("lockd: GRANTED_RES   called\n");
484
485        nlmsvc_grant_reply(&argp->cookie, argp->status);
486        return rpc_success;
487}
488
489static __be32
490nlm4svc_proc_unused(struct svc_rqst *rqstp)
491{
492	return rpc_proc_unavail;
493}
494
495
496/*
497 * NLM Server procedures.
498 */
499
 
 
 
 
 
 
 
 
 
 
 
 
 
 
500struct nlm_void			{ int dummy; };
501
 
 
 
 
 
 
 
 
 
502#define	Ck	(1+XDR_QUADLEN(NLM_MAXCOOKIELEN))	/* cookie */
503#define	No	(1+1024/4)				/* netobj */
504#define	St	1					/* status */
505#define	Rg	4					/* range (offset + length) */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
506
507const struct svc_procedure nlmsvc_procedures4[24] = {
508	[NLMPROC_NULL] = {
509		.pc_func = nlm4svc_proc_null,
510		.pc_decode = nlm4svc_decode_void,
511		.pc_encode = nlm4svc_encode_void,
512		.pc_argsize = sizeof(struct nlm_void),
513		.pc_ressize = sizeof(struct nlm_void),
514		.pc_xdrressize = St,
515		.pc_name = "NULL",
516	},
517	[NLMPROC_TEST] = {
518		.pc_func = nlm4svc_proc_test,
519		.pc_decode = nlm4svc_decode_testargs,
520		.pc_encode = nlm4svc_encode_testres,
521		.pc_argsize = sizeof(struct nlm_args),
522		.pc_ressize = sizeof(struct nlm_res),
523		.pc_xdrressize = Ck+St+2+No+Rg,
524		.pc_name = "TEST",
525	},
526	[NLMPROC_LOCK] = {
527		.pc_func = nlm4svc_proc_lock,
528		.pc_decode = nlm4svc_decode_lockargs,
529		.pc_encode = nlm4svc_encode_res,
530		.pc_argsize = sizeof(struct nlm_args),
531		.pc_ressize = sizeof(struct nlm_res),
532		.pc_xdrressize = Ck+St,
533		.pc_name = "LOCK",
534	},
535	[NLMPROC_CANCEL] = {
536		.pc_func = nlm4svc_proc_cancel,
537		.pc_decode = nlm4svc_decode_cancargs,
538		.pc_encode = nlm4svc_encode_res,
539		.pc_argsize = sizeof(struct nlm_args),
540		.pc_ressize = sizeof(struct nlm_res),
541		.pc_xdrressize = Ck+St,
542		.pc_name = "CANCEL",
543	},
544	[NLMPROC_UNLOCK] = {
545		.pc_func = nlm4svc_proc_unlock,
546		.pc_decode = nlm4svc_decode_unlockargs,
547		.pc_encode = nlm4svc_encode_res,
548		.pc_argsize = sizeof(struct nlm_args),
549		.pc_ressize = sizeof(struct nlm_res),
550		.pc_xdrressize = Ck+St,
551		.pc_name = "UNLOCK",
552	},
553	[NLMPROC_GRANTED] = {
554		.pc_func = nlm4svc_proc_granted,
555		.pc_decode = nlm4svc_decode_testargs,
556		.pc_encode = nlm4svc_encode_res,
557		.pc_argsize = sizeof(struct nlm_args),
558		.pc_ressize = sizeof(struct nlm_res),
559		.pc_xdrressize = Ck+St,
560		.pc_name = "GRANTED",
561	},
562	[NLMPROC_TEST_MSG] = {
563		.pc_func = nlm4svc_proc_test_msg,
564		.pc_decode = nlm4svc_decode_testargs,
565		.pc_encode = nlm4svc_encode_void,
566		.pc_argsize = sizeof(struct nlm_args),
567		.pc_ressize = sizeof(struct nlm_void),
568		.pc_xdrressize = St,
569		.pc_name = "TEST_MSG",
570	},
571	[NLMPROC_LOCK_MSG] = {
572		.pc_func = nlm4svc_proc_lock_msg,
573		.pc_decode = nlm4svc_decode_lockargs,
574		.pc_encode = nlm4svc_encode_void,
575		.pc_argsize = sizeof(struct nlm_args),
576		.pc_ressize = sizeof(struct nlm_void),
577		.pc_xdrressize = St,
578		.pc_name = "LOCK_MSG",
579	},
580	[NLMPROC_CANCEL_MSG] = {
581		.pc_func = nlm4svc_proc_cancel_msg,
582		.pc_decode = nlm4svc_decode_cancargs,
583		.pc_encode = nlm4svc_encode_void,
584		.pc_argsize = sizeof(struct nlm_args),
585		.pc_ressize = sizeof(struct nlm_void),
586		.pc_xdrressize = St,
587		.pc_name = "CANCEL_MSG",
588	},
589	[NLMPROC_UNLOCK_MSG] = {
590		.pc_func = nlm4svc_proc_unlock_msg,
591		.pc_decode = nlm4svc_decode_unlockargs,
592		.pc_encode = nlm4svc_encode_void,
593		.pc_argsize = sizeof(struct nlm_args),
594		.pc_ressize = sizeof(struct nlm_void),
595		.pc_xdrressize = St,
596		.pc_name = "UNLOCK_MSG",
597	},
598	[NLMPROC_GRANTED_MSG] = {
599		.pc_func = nlm4svc_proc_granted_msg,
600		.pc_decode = nlm4svc_decode_testargs,
601		.pc_encode = nlm4svc_encode_void,
602		.pc_argsize = sizeof(struct nlm_args),
603		.pc_ressize = sizeof(struct nlm_void),
604		.pc_xdrressize = St,
605		.pc_name = "GRANTED_MSG",
606	},
607	[NLMPROC_TEST_RES] = {
608		.pc_func = nlm4svc_proc_null,
609		.pc_decode = nlm4svc_decode_void,
610		.pc_encode = nlm4svc_encode_void,
611		.pc_argsize = sizeof(struct nlm_res),
612		.pc_ressize = sizeof(struct nlm_void),
613		.pc_xdrressize = St,
614		.pc_name = "TEST_RES",
615	},
616	[NLMPROC_LOCK_RES] = {
617		.pc_func = nlm4svc_proc_null,
618		.pc_decode = nlm4svc_decode_void,
619		.pc_encode = nlm4svc_encode_void,
620		.pc_argsize = sizeof(struct nlm_res),
621		.pc_ressize = sizeof(struct nlm_void),
622		.pc_xdrressize = St,
623		.pc_name = "LOCK_RES",
624	},
625	[NLMPROC_CANCEL_RES] = {
626		.pc_func = nlm4svc_proc_null,
627		.pc_decode = nlm4svc_decode_void,
628		.pc_encode = nlm4svc_encode_void,
629		.pc_argsize = sizeof(struct nlm_res),
630		.pc_ressize = sizeof(struct nlm_void),
631		.pc_xdrressize = St,
632		.pc_name = "CANCEL_RES",
633	},
634	[NLMPROC_UNLOCK_RES] = {
635		.pc_func = nlm4svc_proc_null,
636		.pc_decode = nlm4svc_decode_void,
637		.pc_encode = nlm4svc_encode_void,
638		.pc_argsize = sizeof(struct nlm_res),
639		.pc_ressize = sizeof(struct nlm_void),
640		.pc_xdrressize = St,
641		.pc_name = "UNLOCK_RES",
642	},
643	[NLMPROC_GRANTED_RES] = {
644		.pc_func = nlm4svc_proc_granted_res,
645		.pc_decode = nlm4svc_decode_res,
646		.pc_encode = nlm4svc_encode_void,
647		.pc_argsize = sizeof(struct nlm_res),
648		.pc_ressize = sizeof(struct nlm_void),
649		.pc_xdrressize = St,
650		.pc_name = "GRANTED_RES",
651	},
652	[NLMPROC_NSM_NOTIFY] = {
653		.pc_func = nlm4svc_proc_sm_notify,
654		.pc_decode = nlm4svc_decode_reboot,
655		.pc_encode = nlm4svc_encode_void,
656		.pc_argsize = sizeof(struct nlm_reboot),
657		.pc_ressize = sizeof(struct nlm_void),
658		.pc_xdrressize = St,
659		.pc_name = "SM_NOTIFY",
660	},
661	[17] = {
662		.pc_func = nlm4svc_proc_unused,
663		.pc_decode = nlm4svc_decode_void,
664		.pc_encode = nlm4svc_encode_void,
665		.pc_argsize = sizeof(struct nlm_void),
666		.pc_ressize = sizeof(struct nlm_void),
667		.pc_xdrressize = 0,
668		.pc_name = "UNUSED",
669	},
670	[18] = {
671		.pc_func = nlm4svc_proc_unused,
672		.pc_decode = nlm4svc_decode_void,
673		.pc_encode = nlm4svc_encode_void,
674		.pc_argsize = sizeof(struct nlm_void),
675		.pc_ressize = sizeof(struct nlm_void),
676		.pc_xdrressize = 0,
677		.pc_name = "UNUSED",
678	},
679	[19] = {
680		.pc_func = nlm4svc_proc_unused,
681		.pc_decode = nlm4svc_decode_void,
682		.pc_encode = nlm4svc_encode_void,
683		.pc_argsize = sizeof(struct nlm_void),
684		.pc_ressize = sizeof(struct nlm_void),
685		.pc_xdrressize = 0,
686		.pc_name = "UNUSED",
687	},
688	[NLMPROC_SHARE] = {
689		.pc_func = nlm4svc_proc_share,
690		.pc_decode = nlm4svc_decode_shareargs,
691		.pc_encode = nlm4svc_encode_shareres,
692		.pc_argsize = sizeof(struct nlm_args),
693		.pc_ressize = sizeof(struct nlm_res),
694		.pc_xdrressize = Ck+St+1,
695		.pc_name = "SHARE",
696	},
697	[NLMPROC_UNSHARE] = {
698		.pc_func = nlm4svc_proc_unshare,
699		.pc_decode = nlm4svc_decode_shareargs,
700		.pc_encode = nlm4svc_encode_shareres,
701		.pc_argsize = sizeof(struct nlm_args),
702		.pc_ressize = sizeof(struct nlm_res),
703		.pc_xdrressize = Ck+St+1,
704		.pc_name = "UNSHARE",
705	},
706	[NLMPROC_NM_LOCK] = {
707		.pc_func = nlm4svc_proc_nm_lock,
708		.pc_decode = nlm4svc_decode_lockargs,
709		.pc_encode = nlm4svc_encode_res,
710		.pc_argsize = sizeof(struct nlm_args),
711		.pc_ressize = sizeof(struct nlm_res),
712		.pc_xdrressize = Ck+St,
713		.pc_name = "NM_LOCK",
714	},
715	[NLMPROC_FREE_ALL] = {
716		.pc_func = nlm4svc_proc_free_all,
717		.pc_decode = nlm4svc_decode_notify,
718		.pc_encode = nlm4svc_encode_void,
719		.pc_argsize = sizeof(struct nlm_args),
720		.pc_ressize = sizeof(struct nlm_void),
721		.pc_xdrressize = St,
722		.pc_name = "FREE_ALL",
723	},
724};
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * linux/fs/lockd/svc4proc.c
  4 *
  5 * Lockd server procedures. We don't implement the NLM_*_RES 
  6 * procedures because we don't use the async procedures.
  7 *
  8 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
  9 */
 10
 11#include <linux/types.h>
 12#include <linux/time.h>
 13#include <linux/lockd/lockd.h>
 14#include <linux/lockd/share.h>
 15#include <linux/sunrpc/svc_xprt.h>
 16
 17#define NLMDBG_FACILITY		NLMDBG_CLIENT
 18
 19/*
 20 * Obtain client and file from arguments
 21 */
 22static __be32
 23nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
 24			struct nlm_host **hostp, struct nlm_file **filp)
 25{
 26	struct nlm_host		*host = NULL;
 27	struct nlm_file		*file = NULL;
 28	struct nlm_lock		*lock = &argp->lock;
 29	__be32			error = 0;
 30
 31	/* nfsd callbacks must have been installed for this procedure */
 32	if (!nlmsvc_ops)
 33		return nlm_lck_denied_nolocks;
 34
 35	/* Obtain host handle */
 36	if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
 37	 || (argp->monitor && nsm_monitor(host) < 0))
 38		goto no_locks;
 39	*hostp = host;
 40
 41	/* Obtain file pointer. Not used by FREE_ALL call. */
 42	if (filp != NULL) {
 43		if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
 44			goto no_locks;
 45		*filp = file;
 46
 47		/* Set up the missing parts of the file_lock structure */
 48		lock->fl.fl_file  = file->f_file;
 49		lock->fl.fl_pid = current->tgid;
 50		lock->fl.fl_lmops = &nlmsvc_lock_operations;
 51		nlmsvc_locks_init_private(&lock->fl, host, (pid_t)lock->svid);
 52		if (!lock->fl.fl_owner) {
 53			/* lockowner allocation has failed */
 54			nlmsvc_release_host(host);
 55			return nlm_lck_denied_nolocks;
 56		}
 57	}
 58
 59	return 0;
 60
 61no_locks:
 62	nlmsvc_release_host(host);
 63 	if (error)
 64		return error;	
 65	return nlm_lck_denied_nolocks;
 66}
 67
 68/*
 69 * NULL: Test for presence of service
 70 */
 71static __be32
 72nlm4svc_proc_null(struct svc_rqst *rqstp)
 73{
 74	dprintk("lockd: NULL          called\n");
 75	return rpc_success;
 76}
 77
 78/*
 79 * TEST: Check for conflicting lock
 80 */
 81static __be32
 82__nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_res *resp)
 83{
 84	struct nlm_args *argp = rqstp->rq_argp;
 85	struct nlm_host	*host;
 86	struct nlm_file	*file;
 87	__be32 rc = rpc_success;
 88
 89	dprintk("lockd: TEST4        called\n");
 90	resp->cookie = argp->cookie;
 91
 92	/* Obtain client and file */
 93	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
 94		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
 95
 96	/* Now check for conflicting locks */
 97	resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
 98	if (resp->status == nlm_drop_reply)
 99		rc = rpc_drop_reply;
100	else
101		dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
102
103	nlmsvc_release_lockowner(&argp->lock);
104	nlmsvc_release_host(host);
105	nlm_release_file(file);
106	return rc;
107}
108
109static __be32
110nlm4svc_proc_test(struct svc_rqst *rqstp)
111{
112	return __nlm4svc_proc_test(rqstp, rqstp->rq_resp);
113}
114
115static __be32
116__nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_res *resp)
117{
118	struct nlm_args *argp = rqstp->rq_argp;
119	struct nlm_host	*host;
120	struct nlm_file	*file;
121	__be32 rc = rpc_success;
122
123	dprintk("lockd: LOCK          called\n");
124
125	resp->cookie = argp->cookie;
126
127	/* Obtain client and file */
128	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
129		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
130
131#if 0
132	/* If supplied state doesn't match current state, we assume it's
133	 * an old request that time-warped somehow. Any error return would
134	 * do in this case because it's irrelevant anyway.
135	 *
136	 * NB: We don't retrieve the remote host's state yet.
137	 */
138	if (host->h_nsmstate && host->h_nsmstate != argp->state) {
139		resp->status = nlm_lck_denied_nolocks;
140	} else
141#endif
142
143	/* Now try to lock the file */
144	resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
145					argp->block, &argp->cookie,
146					argp->reclaim);
147	if (resp->status == nlm_drop_reply)
148		rc = rpc_drop_reply;
149	else
150		dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
151
152	nlmsvc_release_lockowner(&argp->lock);
153	nlmsvc_release_host(host);
154	nlm_release_file(file);
155	return rc;
156}
157
158static __be32
159nlm4svc_proc_lock(struct svc_rqst *rqstp)
160{
161	return __nlm4svc_proc_lock(rqstp, rqstp->rq_resp);
162}
163
164static __be32
165__nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_res *resp)
166{
167	struct nlm_args *argp = rqstp->rq_argp;
168	struct nlm_host	*host;
169	struct nlm_file	*file;
170
171	dprintk("lockd: CANCEL        called\n");
172
173	resp->cookie = argp->cookie;
174
175	/* Don't accept requests during grace period */
176	if (locks_in_grace(SVC_NET(rqstp))) {
177		resp->status = nlm_lck_denied_grace_period;
178		return rpc_success;
179	}
180
181	/* Obtain client and file */
182	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
183		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
184
185	/* Try to cancel request. */
186	resp->status = nlmsvc_cancel_blocked(SVC_NET(rqstp), file, &argp->lock);
187
188	dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
189	nlmsvc_release_lockowner(&argp->lock);
190	nlmsvc_release_host(host);
191	nlm_release_file(file);
192	return rpc_success;
193}
194
195static __be32
196nlm4svc_proc_cancel(struct svc_rqst *rqstp)
197{
198	return __nlm4svc_proc_cancel(rqstp, rqstp->rq_resp);
199}
200
201/*
202 * UNLOCK: release a lock
203 */
204static __be32
205__nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_res *resp)
206{
207	struct nlm_args *argp = rqstp->rq_argp;
208	struct nlm_host	*host;
209	struct nlm_file	*file;
210
211	dprintk("lockd: UNLOCK        called\n");
212
213	resp->cookie = argp->cookie;
214
215	/* Don't accept new lock requests during grace period */
216	if (locks_in_grace(SVC_NET(rqstp))) {
217		resp->status = nlm_lck_denied_grace_period;
218		return rpc_success;
219	}
220
221	/* Obtain client and file */
222	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
223		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
224
225	/* Now try to remove the lock */
226	resp->status = nlmsvc_unlock(SVC_NET(rqstp), file, &argp->lock);
227
228	dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
229	nlmsvc_release_lockowner(&argp->lock);
230	nlmsvc_release_host(host);
231	nlm_release_file(file);
232	return rpc_success;
233}
234
235static __be32
236nlm4svc_proc_unlock(struct svc_rqst *rqstp)
237{
238	return __nlm4svc_proc_unlock(rqstp, rqstp->rq_resp);
239}
240
241/*
242 * GRANTED: A server calls us to tell that a process' lock request
243 * was granted
244 */
245static __be32
246__nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_res *resp)
247{
248	struct nlm_args *argp = rqstp->rq_argp;
249
250	resp->cookie = argp->cookie;
251
252	dprintk("lockd: GRANTED       called\n");
253	resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
254	dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
255	return rpc_success;
256}
257
258static __be32
259nlm4svc_proc_granted(struct svc_rqst *rqstp)
260{
261	return __nlm4svc_proc_granted(rqstp, rqstp->rq_resp);
262}
263
264/*
265 * This is the generic lockd callback for async RPC calls
266 */
267static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
268{
269	dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
270			-task->tk_status);
271}
272
273static void nlm4svc_callback_release(void *data)
274{
275	nlmsvc_release_call(data);
276}
277
278static const struct rpc_call_ops nlm4svc_callback_ops = {
279	.rpc_call_done = nlm4svc_callback_exit,
280	.rpc_release = nlm4svc_callback_release,
281};
282
283/*
284 * `Async' versions of the above service routines. They aren't really,
285 * because we send the callback before the reply proper. I hope this
286 * doesn't break any clients.
287 */
288static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc,
289		__be32 (*func)(struct svc_rqst *,  struct nlm_res *))
290{
291	struct nlm_args *argp = rqstp->rq_argp;
292	struct nlm_host	*host;
293	struct nlm_rqst	*call;
294	__be32 stat;
295
296	host = nlmsvc_lookup_host(rqstp,
297				  argp->lock.caller,
298				  argp->lock.len);
299	if (host == NULL)
300		return rpc_system_err;
301
302	call = nlm_alloc_call(host);
303	nlmsvc_release_host(host);
304	if (call == NULL)
305		return rpc_system_err;
306
307	stat = func(rqstp, &call->a_res);
308	if (stat != 0) {
309		nlmsvc_release_call(call);
310		return stat;
311	}
312
313	call->a_flags = RPC_TASK_ASYNC;
314	if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
315		return rpc_system_err;
316	return rpc_success;
317}
318
319static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp)
320{
321	dprintk("lockd: TEST_MSG      called\n");
322	return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, __nlm4svc_proc_test);
323}
324
325static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp)
326{
327	dprintk("lockd: LOCK_MSG      called\n");
328	return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, __nlm4svc_proc_lock);
329}
330
331static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp)
332{
333	dprintk("lockd: CANCEL_MSG    called\n");
334	return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, __nlm4svc_proc_cancel);
335}
336
337static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp)
338{
339	dprintk("lockd: UNLOCK_MSG    called\n");
340	return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, __nlm4svc_proc_unlock);
341}
342
343static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp)
344{
345	dprintk("lockd: GRANTED_MSG   called\n");
346	return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, __nlm4svc_proc_granted);
347}
348
349/*
350 * SHARE: create a DOS share or alter existing share.
351 */
352static __be32
353nlm4svc_proc_share(struct svc_rqst *rqstp)
354{
355	struct nlm_args *argp = rqstp->rq_argp;
356	struct nlm_res *resp = rqstp->rq_resp;
357	struct nlm_host	*host;
358	struct nlm_file	*file;
359
360	dprintk("lockd: SHARE         called\n");
361
362	resp->cookie = argp->cookie;
363
364	/* Don't accept new lock requests during grace period */
365	if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
366		resp->status = nlm_lck_denied_grace_period;
367		return rpc_success;
368	}
369
370	/* Obtain client and file */
371	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
372		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
373
374	/* Now try to create the share */
375	resp->status = nlmsvc_share_file(host, file, argp);
376
377	dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
378	nlmsvc_release_lockowner(&argp->lock);
379	nlmsvc_release_host(host);
380	nlm_release_file(file);
381	return rpc_success;
382}
383
384/*
385 * UNSHARE: Release a DOS share.
386 */
387static __be32
388nlm4svc_proc_unshare(struct svc_rqst *rqstp)
389{
390	struct nlm_args *argp = rqstp->rq_argp;
391	struct nlm_res *resp = rqstp->rq_resp;
392	struct nlm_host	*host;
393	struct nlm_file	*file;
394
395	dprintk("lockd: UNSHARE       called\n");
396
397	resp->cookie = argp->cookie;
398
399	/* Don't accept requests during grace period */
400	if (locks_in_grace(SVC_NET(rqstp))) {
401		resp->status = nlm_lck_denied_grace_period;
402		return rpc_success;
403	}
404
405	/* Obtain client and file */
406	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
407		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
408
409	/* Now try to lock the file */
410	resp->status = nlmsvc_unshare_file(host, file, argp);
411
412	dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
413	nlmsvc_release_lockowner(&argp->lock);
414	nlmsvc_release_host(host);
415	nlm_release_file(file);
416	return rpc_success;
417}
418
419/*
420 * NM_LOCK: Create an unmonitored lock
421 */
422static __be32
423nlm4svc_proc_nm_lock(struct svc_rqst *rqstp)
424{
425	struct nlm_args *argp = rqstp->rq_argp;
426
427	dprintk("lockd: NM_LOCK       called\n");
428
429	argp->monitor = 0;		/* just clean the monitor flag */
430	return nlm4svc_proc_lock(rqstp);
431}
432
433/*
434 * FREE_ALL: Release all locks and shares held by client
435 */
436static __be32
437nlm4svc_proc_free_all(struct svc_rqst *rqstp)
438{
439	struct nlm_args *argp = rqstp->rq_argp;
440	struct nlm_host	*host;
441
442	/* Obtain client */
443	if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
444		return rpc_success;
445
446	nlmsvc_free_host_resources(host);
447	nlmsvc_release_host(host);
448	return rpc_success;
449}
450
451/*
452 * SM_NOTIFY: private callback from statd (not part of official NLM proto)
453 */
454static __be32
455nlm4svc_proc_sm_notify(struct svc_rqst *rqstp)
456{
457	struct nlm_reboot *argp = rqstp->rq_argp;
458
459	dprintk("lockd: SM_NOTIFY     called\n");
460
461	if (!nlm_privileged_requester(rqstp)) {
462		char buf[RPC_MAX_ADDRBUFLEN];
463		printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
464				svc_print_addr(rqstp, buf, sizeof(buf)));
465		return rpc_system_err;
466	}
467
468	nlm_host_rebooted(SVC_NET(rqstp), argp);
469	return rpc_success;
470}
471
472/*
473 * client sent a GRANTED_RES, let's remove the associated block
474 */
475static __be32
476nlm4svc_proc_granted_res(struct svc_rqst *rqstp)
477{
478	struct nlm_res *argp = rqstp->rq_argp;
479
480        if (!nlmsvc_ops)
481                return rpc_success;
482
483        dprintk("lockd: GRANTED_RES   called\n");
484
485        nlmsvc_grant_reply(&argp->cookie, argp->status);
486        return rpc_success;
487}
488
 
 
 
 
 
 
489
490/*
491 * NLM Server procedures.
492 */
493
494#define nlm4svc_encode_norep	nlm4svc_encode_void
495#define nlm4svc_decode_norep	nlm4svc_decode_void
496#define nlm4svc_decode_testres	nlm4svc_decode_void
497#define nlm4svc_decode_lockres	nlm4svc_decode_void
498#define nlm4svc_decode_unlockres	nlm4svc_decode_void
499#define nlm4svc_decode_cancelres	nlm4svc_decode_void
500#define nlm4svc_decode_grantedres	nlm4svc_decode_void
501
502#define nlm4svc_proc_none	nlm4svc_proc_null
503#define nlm4svc_proc_test_res	nlm4svc_proc_null
504#define nlm4svc_proc_lock_res	nlm4svc_proc_null
505#define nlm4svc_proc_cancel_res	nlm4svc_proc_null
506#define nlm4svc_proc_unlock_res	nlm4svc_proc_null
507
508struct nlm_void			{ int dummy; };
509
510#define PROC(name, xargt, xrest, argt, rest, respsize)	\
511 { .pc_func	= nlm4svc_proc_##name,	\
512   .pc_decode	= nlm4svc_decode_##xargt,	\
513   .pc_encode	= nlm4svc_encode_##xrest,	\
514   .pc_release	= NULL,					\
515   .pc_argsize	= sizeof(struct nlm_##argt),		\
516   .pc_ressize	= sizeof(struct nlm_##rest),		\
517   .pc_xdrressize = respsize,				\
518 }
519#define	Ck	(1+XDR_QUADLEN(NLM_MAXCOOKIELEN))	/* cookie */
520#define	No	(1+1024/4)				/* netobj */
521#define	St	1					/* status */
522#define	Rg	4					/* range (offset + length) */
523const struct svc_procedure nlmsvc_procedures4[] = {
524  PROC(null,		void,		void,		void,	void, 1),
525  PROC(test,		testargs,	testres,	args,	res, Ck+St+2+No+Rg),
526  PROC(lock,		lockargs,	res,		args,	res, Ck+St),
527  PROC(cancel,		cancargs,	res,		args,	res, Ck+St),
528  PROC(unlock,		unlockargs,	res,		args,	res, Ck+St),
529  PROC(granted,		testargs,	res,		args,	res, Ck+St),
530  PROC(test_msg,	testargs,	norep,		args,	void, 1),
531  PROC(lock_msg,	lockargs,	norep,		args,	void, 1),
532  PROC(cancel_msg,	cancargs,	norep,		args,	void, 1),
533  PROC(unlock_msg,	unlockargs,	norep,		args,	void, 1),
534  PROC(granted_msg,	testargs,	norep,		args,	void, 1),
535  PROC(test_res,	testres,	norep,		res,	void, 1),
536  PROC(lock_res,	lockres,	norep,		res,	void, 1),
537  PROC(cancel_res,	cancelres,	norep,		res,	void, 1),
538  PROC(unlock_res,	unlockres,	norep,		res,	void, 1),
539  PROC(granted_res,	res,		norep,		res,	void, 1),
540  /* statd callback */
541  PROC(sm_notify,	reboot,		void,		reboot,	void, 1),
542  PROC(none,		void,		void,		void,	void, 0),
543  PROC(none,		void,		void,		void,	void, 0),
544  PROC(none,		void,		void,		void,	void, 0),
545  PROC(share,		shareargs,	shareres,	args,	res, Ck+St+1),
546  PROC(unshare,		shareargs,	shareres,	args,	res, Ck+St+1),
547  PROC(nm_lock,		lockargs,	res,		args,	res, Ck+St),
548  PROC(free_all,	notify,		void,		args,	void, 1),
549
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
550};