1/*
2 * linux/fs/lockd/svcproc.c
3 *
4 * Lockd server procedures. We don't implement the NLM_*_RES
5 * procedures because we don't use the async procedures.
6 *
7 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
8 */
9
10#include <linux/types.h>
11#include <linux/time.h>
12#include <linux/slab.h>
13#include <linux/in.h>
14#include <linux/sunrpc/svc.h>
15#include <linux/sunrpc/clnt.h>
16#include <linux/nfsd/nfsd.h>
17#include <linux/lockd/lockd.h>
18#include <linux/lockd/share.h>
19#include <linux/lockd/sm_inter.h>
20
21
22#define NLMDBG_FACILITY		NLMDBG_CLIENT
23
24#ifdef CONFIG_LOCKD_V4
25static __be32
26cast_to_nlm(__be32 status, u32 vers)
27{
28	/* Note: status is assumed to be in network byte order !!! */
29	if (vers != 4){
30		switch (status) {
31		case nlm_granted:
32		case nlm_lck_denied:
33		case nlm_lck_denied_nolocks:
34		case nlm_lck_blocked:
35		case nlm_lck_denied_grace_period:
36		case nlm_drop_reply:
37			break;
38		case nlm4_deadlock:
39			status = nlm_lck_denied;
40			break;
41		default:
42			status = nlm_lck_denied_nolocks;
43		}
44	}
45
46	return (status);
47}
48#define	cast_status(status) (cast_to_nlm(status, rqstp->rq_vers))
49#else
50#define cast_status(status) (status)
51#endif
52
53/*
54 * Obtain client and file from arguments
55 */
56static __be32
57nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
58			struct nlm_host **hostp, struct nlm_file **filp)
59{
60	struct nlm_host		*host = NULL;
61	struct nlm_file		*file = NULL;
62	struct nlm_lock		*lock = &argp->lock;
63	__be32			error = 0;
64
65	/* nfsd callbacks must have been installed for this procedure */
66	if (!nlmsvc_ops)
67		return nlm_lck_denied_nolocks;
68
69	/* Obtain host handle */
70	if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
71	 || (argp->monitor && nsm_monitor(host) < 0))
72		goto no_locks;
73	*hostp = host;
74
75	/* Obtain file pointer. Not used by FREE_ALL call. */
76	if (filp != NULL) {
77		if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
78			goto no_locks;
79		*filp = file;
80
81		/* Set up the missing parts of the file_lock structure */
82		lock->fl.fl_file  = file->f_file;
83		lock->fl.fl_owner = (fl_owner_t) host;
84		lock->fl.fl_lmops = &nlmsvc_lock_operations;
85	}
86
87	return 0;
88
89no_locks:
90	if (host)
91		nlm_release_host(host);
92	if (error)
93		return error;
94	return nlm_lck_denied_nolocks;
95}
96
97/*
98 * NULL: Test for presence of service
99 */
100static __be32
101nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
102{
103	dprintk("lockd: NULL          called\n");
104	return rpc_success;
105}
106
107/*
108 * TEST: Check for conflicting lock
109 */
110static __be32
111nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
112				         struct nlm_res  *resp)
113{
114	struct nlm_host	*host;
115	struct nlm_file	*file;
116
117	dprintk("lockd: TEST          called\n");
118	resp->cookie = argp->cookie;
119
120	/* Don't accept test requests during grace period */
121	if (nlmsvc_grace_period) {
122		resp->status = nlm_lck_denied_grace_period;
123		return rpc_success;
124	}
125
126	/* Obtain client and file */
127	if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
128		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
129
130	/* Now check for conflicting locks */
131	resp->status = cast_status(nlmsvc_testlock(rqstp, file, &argp->lock, &resp->lock, &resp->cookie));
132	if (resp->status == nlm_drop_reply)
133		return rpc_drop_reply;
134
135	dprintk("lockd: TEST          status %d vers %d\n",
136		ntohl(resp->status), rqstp->rq_vers);
137	nlm_release_host(host);
138	nlm_release_file(file);
139	return rpc_success;
140}
141
142static __be32
143nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
144				         struct nlm_res  *resp)
145{
146	struct nlm_host	*host;
147	struct nlm_file	*file;
148
149	dprintk("lockd: LOCK          called\n");
150
151	resp->cookie = argp->cookie;
152
153	/* Don't accept new lock requests during grace period */
154	if (nlmsvc_grace_period && !argp->reclaim) {
155		resp->status = nlm_lck_denied_grace_period;
156		return rpc_success;
157	}
158
159	/* Obtain client and file */
160	if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
161		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
162
163
164	/* Now try to lock the file */
165	resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
166					       argp->block, &argp->cookie));
167	if (resp->status == nlm_drop_reply)
168		return rpc_drop_reply;
169
170	dprintk("lockd: LOCK          status %d\n", ntohl(resp->status));
171	nlm_release_host(host);
172	nlm_release_file(file);
173	return rpc_success;
174}
175
176static __be32
177nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
178				           struct nlm_res  *resp)
179{
180	struct nlm_host	*host;
181	struct nlm_file	*file;
182
183	dprintk("lockd: CANCEL        called\n");
184
185	resp->cookie = argp->cookie;
186
187	/* Don't accept requests during grace period */
188	if (nlmsvc_grace_period) {
189		resp->status = nlm_lck_denied_grace_period;
190		return rpc_success;
191	}
192
193	/* Obtain client and file */
194	if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
195		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
196
197	/* Try to cancel request. */
198	resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
199
200	dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
201	nlm_release_host(host);
202	nlm_release_file(file);
203	return rpc_success;
204}
205
206/*
207 * UNLOCK: release a lock
208 */
209static __be32
210nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
211				           struct nlm_res  *resp)
212{
213	struct nlm_host	*host;
214	struct nlm_file	*file;
215
216	dprintk("lockd: UNLOCK        called\n");
217
218	resp->cookie = argp->cookie;
219
220	/* Don't accept new lock requests during grace period */
221	if (nlmsvc_grace_period) {
222		resp->status = nlm_lck_denied_grace_period;
223		return rpc_success;
224	}
225
226	/* Obtain client and file */
227	if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
228		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
229
230	/* Now try to remove the lock */
231	resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
232
233	dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
234	nlm_release_host(host);
235	nlm_release_file(file);
236	return rpc_success;
237}
238
239/*
240 * GRANTED: A server calls us to tell that a process' lock request
241 * was granted
242 */
243static __be32
244nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
245				            struct nlm_res  *resp)
246{
247	resp->cookie = argp->cookie;
248
249	dprintk("lockd: GRANTED       called\n");
250	resp->status = nlmclnt_grant(svc_addr_in(rqstp), &argp->lock);
251	dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
252	return rpc_success;
253}
254
255/*
256 * This is the generic lockd callback for async RPC calls
257 */
258static void nlmsvc_callback_exit(struct rpc_task *task, void *data)
259{
260	dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
261			-task->tk_status);
262}
263
264static void nlmsvc_callback_release(void *data)
265{
266	nlm_release_call(data);
267}
268
269static const struct rpc_call_ops nlmsvc_callback_ops = {
270	.rpc_call_done = nlmsvc_callback_exit,
271	.rpc_release = nlmsvc_callback_release,
272};
273
274/*
275 * `Async' versions of the above service routines. They aren't really,
276 * because we send the callback before the reply proper. I hope this
277 * doesn't break any clients.
278 */
279static __be32 nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
280		__be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
281{
282	struct nlm_host	*host;
283	struct nlm_rqst	*call;
284	__be32 stat;
285
286	host = nlmsvc_lookup_host(rqstp,
287				  argp->lock.caller,
288				  argp->lock.len);
289	if (host == NULL)
290		return rpc_system_err;
291
292	call = nlm_alloc_call(host);
293	if (call == NULL)
294		return rpc_system_err;
295
296	stat = func(rqstp, argp, &call->a_res);
297	if (stat != 0) {
298		nlm_release_call(call);
299		return stat;
300	}
301
302	call->a_flags = RPC_TASK_ASYNC;
303	if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
304		return rpc_system_err;
305	return rpc_success;
306}
307
308static __be32 nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
309					     void	     *resp)
310{
311	dprintk("lockd: TEST_MSG      called\n");
312	return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
313}
314
315static __be32 nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
316					     void	     *resp)
317{
318	dprintk("lockd: LOCK_MSG      called\n");
319	return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
320}
321
322static __be32 nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
323					       void	       *resp)
324{
325	dprintk("lockd: CANCEL_MSG    called\n");
326	return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
327}
328
329static __be32
330nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
331                                               void            *resp)
332{
333	dprintk("lockd: UNLOCK_MSG    called\n");
334	return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
335}
336
337static __be32
338nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
339                                                void            *resp)
340{
341	dprintk("lockd: GRANTED_MSG   called\n");
342	return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
343}
344
345/*
346 * SHARE: create a DOS share or alter existing share.
347 */
348static __be32
349nlmsvc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
350				          struct nlm_res  *resp)
351{
352	struct nlm_host	*host;
353	struct nlm_file	*file;
354
355	dprintk("lockd: SHARE         called\n");
356
357	resp->cookie = argp->cookie;
358
359	/* Don't accept new lock requests during grace period */
360	if (nlmsvc_grace_period && !argp->reclaim) {
361		resp->status = nlm_lck_denied_grace_period;
362		return rpc_success;
363	}
364
365	/* Obtain client and file */
366	if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
367		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
368
369	/* Now try to create the share */
370	resp->status = cast_status(nlmsvc_share_file(host, file, argp));
371
372	dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
373	nlm_release_host(host);
374	nlm_release_file(file);
375	return rpc_success;
376}
377
378/*
379 * UNSHARE: Release a DOS share.
380 */
381static __be32
382nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
383				            struct nlm_res  *resp)
384{
385	struct nlm_host	*host;
386	struct nlm_file	*file;
387
388	dprintk("lockd: UNSHARE       called\n");
389
390	resp->cookie = argp->cookie;
391
392	/* Don't accept requests during grace period */
393	if (nlmsvc_grace_period) {
394		resp->status = nlm_lck_denied_grace_period;
395		return rpc_success;
396	}
397
398	/* Obtain client and file */
399	if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
400		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
401
402	/* Now try to unshare the file */
403	resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
404
405	dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
406	nlm_release_host(host);
407	nlm_release_file(file);
408	return rpc_success;
409}
410
411/*
412 * NM_LOCK: Create an unmonitored lock
413 */
414static __be32
415nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
416				            struct nlm_res  *resp)
417{
418	dprintk("lockd: NM_LOCK       called\n");
419
420	argp->monitor = 0;		/* just clean the monitor flag */
421	return nlmsvc_proc_lock(rqstp, argp, resp);
422}
423
424/*
425 * FREE_ALL: Release all locks and shares held by client
426 */
427static __be32
428nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
429					     void            *resp)
430{
431	struct nlm_host	*host;
432
433	/* Obtain client */
434	if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
435		return rpc_success;
436
437	nlmsvc_free_host_resources(host);
438	nlm_release_host(host);
439	return rpc_success;
440}
441
442/*
443 * SM_NOTIFY: private callback from statd (not part of official NLM proto)
444 */
445static __be32
446nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
447					      void	        *resp)
448{
449	struct sockaddr_in	saddr;
450
451	memcpy(&saddr, svc_addr_in(rqstp), sizeof(saddr));
452
453	dprintk("lockd: SM_NOTIFY     called\n");
454	if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
455	 || ntohs(saddr.sin_port) >= 1024) {
456		char buf[RPC_MAX_ADDRBUFLEN];
457		printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
458				svc_print_addr(rqstp, buf, sizeof(buf)));
459		return rpc_system_err;
460	}
461
462	/* Obtain the host pointer for this NFS server and try to
463	 * reclaim all locks we hold on this server.
464	 */
465	memset(&saddr, 0, sizeof(saddr));
466	saddr.sin_addr.s_addr = argp->addr;
467	nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);
468
469	return rpc_success;
470}
471
472/*
473 * client sent a GRANTED_RES, let's remove the associated block
474 */
475static __be32
476nlmsvc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
477                                                void            *resp)
478{
479	if (!nlmsvc_ops)
480		return rpc_success;
481
482	dprintk("lockd: GRANTED_RES   called\n");
483
484	nlmsvc_grant_reply(&argp->cookie, argp->status);
485	return rpc_success;
486}
487
488/*
489 * NLM Server procedures.
490 */
491
492#define nlmsvc_encode_norep	nlmsvc_encode_void
493#define nlmsvc_decode_norep	nlmsvc_decode_void
494#define nlmsvc_decode_testres	nlmsvc_decode_void
495#define nlmsvc_decode_lockres	nlmsvc_decode_void
496#define nlmsvc_decode_unlockres	nlmsvc_decode_void
497#define nlmsvc_decode_cancelres	nlmsvc_decode_void
498#define nlmsvc_decode_grantedres	nlmsvc_decode_void
499
500#define nlmsvc_proc_none	nlmsvc_proc_null
501#define nlmsvc_proc_test_res	nlmsvc_proc_null
502#define nlmsvc_proc_lock_res	nlmsvc_proc_null
503#define nlmsvc_proc_cancel_res	nlmsvc_proc_null
504#define nlmsvc_proc_unlock_res	nlmsvc_proc_null
505
506struct nlm_void			{ int dummy; };
507
508#define PROC(name, xargt, xrest, argt, rest, respsize)	\
509 { .pc_func	= (svc_procfunc) nlmsvc_proc_##name,	\
510   .pc_decode	= (kxdrproc_t) nlmsvc_decode_##xargt,	\
511   .pc_encode	= (kxdrproc_t) nlmsvc_encode_##xrest,	\
512   .pc_release	= NULL,					\
513   .pc_argsize	= sizeof(struct nlm_##argt),		\
514   .pc_ressize	= sizeof(struct nlm_##rest),		\
515   .pc_xdrressize = respsize,				\
516 }
517
518#define	Ck	(1+XDR_QUADLEN(NLM_MAXCOOKIELEN))	/* cookie */
519#define	St	1				/* status */
520#define	No	(1+1024/4)			/* Net Obj */
521#define	Rg	2				/* range - offset + size */
522
523struct svc_procedure		nlmsvc_procedures[] = {
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, 1),
543  PROC(none,		void,		void,		void,	void, 1),
544  PROC(none,		void,		void,		void,	void, 1),
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, 0),
549
550};
551