1/*
2 * linux/fs/lockd/svc4proc.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/lockd/lockd.h>
13#include <linux/lockd/share.h>
14#include <linux/sunrpc/svc_xprt.h>
15
16#define NLMDBG_FACILITY		NLMDBG_CLIENT
17
18/*
19 * Obtain client and file from arguments
20 */
21static __be32
22nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
23			struct nlm_host **hostp, struct nlm_file **filp)
24{
25	struct nlm_host		*host = NULL;
26	struct nlm_file		*file = NULL;
27	struct nlm_lock		*lock = &argp->lock;
28	__be32			error = 0;
29
30	/* nfsd callbacks must have been installed for this procedure */
31	if (!nlmsvc_ops)
32		return nlm_lck_denied_nolocks;
33
34	/* Obtain host handle */
35	if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
36	 || (argp->monitor && nsm_monitor(host) < 0))
37		goto no_locks;
38	*hostp = host;
39
40	/* Obtain file pointer. Not used by FREE_ALL call. */
41	if (filp != NULL) {
42		if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
43			goto no_locks;
44		*filp = file;
45
46		/* Set up the missing parts of the file_lock structure */
47		lock->fl.fl_file  = file->f_file;
48		lock->fl.fl_owner = (fl_owner_t) host;
49		lock->fl.fl_lmops = &nlmsvc_lock_operations;
50	}
51
52	return 0;
53
54no_locks:
55	nlmsvc_release_host(host);
56 	if (error)
57		return error;
58	return nlm_lck_denied_nolocks;
59}
60
61/*
62 * NULL: Test for presence of service
63 */
64static __be32
65nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
66{
67	dprintk("lockd: NULL          called\n");
68	return rpc_success;
69}
70
71/*
72 * TEST: Check for conflicting lock
73 */
74static __be32
75nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
76				         struct nlm_res  *resp)
77{
78	struct nlm_host	*host;
79	struct nlm_file	*file;
80	__be32 rc = rpc_success;
81
82	dprintk("lockd: TEST4        called\n");
83	resp->cookie = argp->cookie;
84
85	/* Obtain client and file */
86	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
87		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
88
89	/* Now check for conflicting locks */
90	resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
91	if (resp->status == nlm_drop_reply)
92		rc = rpc_drop_reply;
93	else
94		dprintk("lockd: TEST4        status %d\n", ntohl(resp->status));
95
96	nlmsvc_release_host(host);
97	nlm_release_file(file);
98	return rc;
99}
100
101static __be32
102nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
103				         struct nlm_res  *resp)
104{
105	struct nlm_host	*host;
106	struct nlm_file	*file;
107	__be32 rc = rpc_success;
108
109	dprintk("lockd: LOCK          called\n");
110
111	resp->cookie = argp->cookie;
112
113	/* Obtain client and file */
114	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
115		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
116
117#if 0
118	/* If supplied state doesn't match current state, we assume it's
119	 * an old request that time-warped somehow. Any error return would
120	 * do in this case because it's irrelevant anyway.
121	 *
122	 * NB: We don't retrieve the remote host's state yet.
123	 */
124	if (host->h_nsmstate && host->h_nsmstate != argp->state) {
125		resp->status = nlm_lck_denied_nolocks;
126	} else
127#endif
128
129	/* Now try to lock the file */
130	resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
131					argp->block, &argp->cookie,
132					argp->reclaim);
133	if (resp->status == nlm_drop_reply)
134		rc = rpc_drop_reply;
135	else
136		dprintk("lockd: LOCK         status %d\n", ntohl(resp->status));
137
138	nlmsvc_release_host(host);
139	nlm_release_file(file);
140	return rc;
141}
142
143static __be32
144nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
145				           struct nlm_res  *resp)
146{
147	struct nlm_host	*host;
148	struct nlm_file	*file;
149
150	dprintk("lockd: CANCEL        called\n");
151
152	resp->cookie = argp->cookie;
153
154	/* Don't accept requests during grace period */
155	if (locks_in_grace(SVC_NET(rqstp))) {
156		resp->status = nlm_lck_denied_grace_period;
157		return rpc_success;
158	}
159
160	/* Obtain client and file */
161	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
162		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
163
164	/* Try to cancel request. */
165	resp->status = nlmsvc_cancel_blocked(SVC_NET(rqstp), file, &argp->lock);
166
167	dprintk("lockd: CANCEL        status %d\n", ntohl(resp->status));
168	nlmsvc_release_host(host);
169	nlm_release_file(file);
170	return rpc_success;
171}
172
173/*
174 * UNLOCK: release a lock
175 */
176static __be32
177nlm4svc_proc_unlock(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: UNLOCK        called\n");
184
185	resp->cookie = argp->cookie;
186
187	/* Don't accept new lock requests during grace period */
188	if (locks_in_grace(SVC_NET(rqstp))) {
189		resp->status = nlm_lck_denied_grace_period;
190		return rpc_success;
191	}
192
193	/* Obtain client and file */
194	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
195		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
196
197	/* Now try to remove the lock */
198	resp->status = nlmsvc_unlock(SVC_NET(rqstp), file, &argp->lock);
199
200	dprintk("lockd: UNLOCK        status %d\n", ntohl(resp->status));
201	nlmsvc_release_host(host);
202	nlm_release_file(file);
203	return rpc_success;
204}
205
206/*
207 * GRANTED: A server calls us to tell that a process' lock request
208 * was granted
209 */
210static __be32
211nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
212				            struct nlm_res  *resp)
213{
214	resp->cookie = argp->cookie;
215
216	dprintk("lockd: GRANTED       called\n");
217	resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
218	dprintk("lockd: GRANTED       status %d\n", ntohl(resp->status));
219	return rpc_success;
220}
221
222/*
223 * This is the generic lockd callback for async RPC calls
224 */
225static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
226{
227	dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
228			-task->tk_status);
229}
230
231static void nlm4svc_callback_release(void *data)
232{
233	nlmsvc_release_call(data);
234}
235
236static const struct rpc_call_ops nlm4svc_callback_ops = {
237	.rpc_call_done = nlm4svc_callback_exit,
238	.rpc_release = nlm4svc_callback_release,
239};
240
241/*
242 * `Async' versions of the above service routines. They aren't really,
243 * because we send the callback before the reply proper. I hope this
244 * doesn't break any clients.
245 */
246static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
247		__be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
248{
249	struct nlm_host	*host;
250	struct nlm_rqst	*call;
251	__be32 stat;
252
253	host = nlmsvc_lookup_host(rqstp,
254				  argp->lock.caller,
255				  argp->lock.len);
256	if (host == NULL)
257		return rpc_system_err;
258
259	call = nlm_alloc_call(host);
260	nlmsvc_release_host(host);
261	if (call == NULL)
262		return rpc_system_err;
263
264	stat = func(rqstp, argp, &call->a_res);
265	if (stat != 0) {
266		nlmsvc_release_call(call);
267		return stat;
268	}
269
270	call->a_flags = RPC_TASK_ASYNC;
271	if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
272		return rpc_system_err;
273	return rpc_success;
274}
275
276static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
277					     void	     *resp)
278{
279	dprintk("lockd: TEST_MSG      called\n");
280	return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
281}
282
283static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
284					     void	     *resp)
285{
286	dprintk("lockd: LOCK_MSG      called\n");
287	return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
288}
289
290static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
291					       void	       *resp)
292{
293	dprintk("lockd: CANCEL_MSG    called\n");
294	return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
295}
296
297static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
298                                               void            *resp)
299{
300	dprintk("lockd: UNLOCK_MSG    called\n");
301	return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
302}
303
304static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
305                                                void            *resp)
306{
307	dprintk("lockd: GRANTED_MSG   called\n");
308	return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
309}
310
311/*
312 * SHARE: create a DOS share or alter existing share.
313 */
314static __be32
315nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
316				          struct nlm_res  *resp)
317{
318	struct nlm_host	*host;
319	struct nlm_file	*file;
320
321	dprintk("lockd: SHARE         called\n");
322
323	resp->cookie = argp->cookie;
324
325	/* Don't accept new lock requests during grace period */
326	if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
327		resp->status = nlm_lck_denied_grace_period;
328		return rpc_success;
329	}
330
331	/* Obtain client and file */
332	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
333		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
334
335	/* Now try to create the share */
336	resp->status = nlmsvc_share_file(host, file, argp);
337
338	dprintk("lockd: SHARE         status %d\n", ntohl(resp->status));
339	nlmsvc_release_host(host);
340	nlm_release_file(file);
341	return rpc_success;
342}
343
344/*
345 * UNSHARE: Release a DOS share.
346 */
347static __be32
348nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
349				            struct nlm_res  *resp)
350{
351	struct nlm_host	*host;
352	struct nlm_file	*file;
353
354	dprintk("lockd: UNSHARE       called\n");
355
356	resp->cookie = argp->cookie;
357
358	/* Don't accept requests during grace period */
359	if (locks_in_grace(SVC_NET(rqstp))) {
360		resp->status = nlm_lck_denied_grace_period;
361		return rpc_success;
362	}
363
364	/* Obtain client and file */
365	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
366		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
367
368	/* Now try to lock the file */
369	resp->status = nlmsvc_unshare_file(host, file, argp);
370
371	dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));
372	nlmsvc_release_host(host);
373	nlm_release_file(file);
374	return rpc_success;
375}
376
377/*
378 * NM_LOCK: Create an unmonitored lock
379 */
380static __be32
381nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
382				            struct nlm_res  *resp)
383{
384	dprintk("lockd: NM_LOCK       called\n");
385
386	argp->monitor = 0;		/* just clean the monitor flag */
387	return nlm4svc_proc_lock(rqstp, argp, resp);
388}
389
390/*
391 * FREE_ALL: Release all locks and shares held by client
392 */
393static __be32
394nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
395					     void            *resp)
396{
397	struct nlm_host	*host;
398
399	/* Obtain client */
400	if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
401		return rpc_success;
402
403	nlmsvc_free_host_resources(host);
404	nlmsvc_release_host(host);
405	return rpc_success;
406}
407
408/*
409 * SM_NOTIFY: private callback from statd (not part of official NLM proto)
410 */
411static __be32
412nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
413					      void	        *resp)
414{
415	dprintk("lockd: SM_NOTIFY     called\n");
416
417	if (!nlm_privileged_requester(rqstp)) {
418		char buf[RPC_MAX_ADDRBUFLEN];
419		printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
420				svc_print_addr(rqstp, buf, sizeof(buf)));
421		return rpc_system_err;
422	}
423
424	nlm_host_rebooted(SVC_NET(rqstp), argp);
425	return rpc_success;
426}
427
428/*
429 * client sent a GRANTED_RES, let's remove the associated block
430 */
431static __be32
432nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
433                                                void            *resp)
434{
435        if (!nlmsvc_ops)
436                return rpc_success;
437
438        dprintk("lockd: GRANTED_RES   called\n");
439
440        nlmsvc_grant_reply(&argp->cookie, argp->status);
441        return rpc_success;
442}
443
444
445/*
446 * NLM Server procedures.
447 */
448
449#define nlm4svc_encode_norep	nlm4svc_encode_void
450#define nlm4svc_decode_norep	nlm4svc_decode_void
451#define nlm4svc_decode_testres	nlm4svc_decode_void
452#define nlm4svc_decode_lockres	nlm4svc_decode_void
453#define nlm4svc_decode_unlockres	nlm4svc_decode_void
454#define nlm4svc_decode_cancelres	nlm4svc_decode_void
455#define nlm4svc_decode_grantedres	nlm4svc_decode_void
456
457#define nlm4svc_proc_none	nlm4svc_proc_null
458#define nlm4svc_proc_test_res	nlm4svc_proc_null
459#define nlm4svc_proc_lock_res	nlm4svc_proc_null
460#define nlm4svc_proc_cancel_res	nlm4svc_proc_null
461#define nlm4svc_proc_unlock_res	nlm4svc_proc_null
462
463struct nlm_void			{ int dummy; };
464
465#define PROC(name, xargt, xrest, argt, rest, respsize)	\
466 { .pc_func	= (svc_procfunc) nlm4svc_proc_##name,	\
467   .pc_decode	= (kxdrproc_t) nlm4svc_decode_##xargt,	\
468   .pc_encode	= (kxdrproc_t) nlm4svc_encode_##xrest,	\
469   .pc_release	= NULL,					\
470   .pc_argsize	= sizeof(struct nlm_##argt),		\
471   .pc_ressize	= sizeof(struct nlm_##rest),		\
472   .pc_xdrressize = respsize,				\
473 }
474#define	Ck	(1+XDR_QUADLEN(NLM_MAXCOOKIELEN))	/* cookie */
475#define	No	(1+1024/4)				/* netobj */
476#define	St	1					/* status */
477#define	Rg	4					/* range (offset + length) */
478struct svc_procedure		nlmsvc_procedures4[] = {
479  PROC(null,		void,		void,		void,	void, 1),
480  PROC(test,		testargs,	testres,	args,	res, Ck+St+2+No+Rg),
481  PROC(lock,		lockargs,	res,		args,	res, Ck+St),
482  PROC(cancel,		cancargs,	res,		args,	res, Ck+St),
483  PROC(unlock,		unlockargs,	res,		args,	res, Ck+St),
484  PROC(granted,		testargs,	res,		args,	res, Ck+St),
485  PROC(test_msg,	testargs,	norep,		args,	void, 1),
486  PROC(lock_msg,	lockargs,	norep,		args,	void, 1),
487  PROC(cancel_msg,	cancargs,	norep,		args,	void, 1),
488  PROC(unlock_msg,	unlockargs,	norep,		args,	void, 1),
489  PROC(granted_msg,	testargs,	norep,		args,	void, 1),
490  PROC(test_res,	testres,	norep,		res,	void, 1),
491  PROC(lock_res,	lockres,	norep,		res,	void, 1),
492  PROC(cancel_res,	cancelres,	norep,		res,	void, 1),
493  PROC(unlock_res,	unlockres,	norep,		res,	void, 1),
494  PROC(granted_res,	res,		norep,		res,	void, 1),
495  /* statd callback */
496  PROC(sm_notify,	reboot,		void,		reboot,	void, 1),
497  PROC(none,		void,		void,		void,	void, 0),
498  PROC(none,		void,		void,		void,	void, 0),
499  PROC(none,		void,		void,		void,	void, 0),
500  PROC(share,		shareargs,	shareres,	args,	res, Ck+St+1),
501  PROC(unshare,		shareargs,	shareres,	args,	res, Ck+St+1),
502  PROC(nm_lock,		lockargs,	res,		args,	res, Ck+St),
503  PROC(free_all,	notify,		void,		args,	void, 1),
504
505};
506