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 */
22 static __be32
nlm4svc_retrieve_args(struct svc_rqst * rqstp,struct nlm_args * argp,struct nlm_host ** hostp,struct nlm_file ** filp)23 nlm4svc_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_owner = (fl_owner_t) host;
50 lock->fl.fl_lmops = &nlmsvc_lock_operations;
51 }
52
53 return 0;
54
55 no_locks:
56 nlmsvc_release_host(host);
57 if (error)
58 return error;
59 return nlm_lck_denied_nolocks;
60 }
61
62 /*
63 * NULL: Test for presence of service
64 */
65 static __be32
nlm4svc_proc_null(struct svc_rqst * rqstp)66 nlm4svc_proc_null(struct svc_rqst *rqstp)
67 {
68 dprintk("lockd: NULL called\n");
69 return rpc_success;
70 }
71
72 /*
73 * TEST: Check for conflicting lock
74 */
75 static __be32
__nlm4svc_proc_test(struct svc_rqst * rqstp,struct nlm_res * resp)76 __nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_res *resp)
77 {
78 struct nlm_args *argp = rqstp->rq_argp;
79 struct nlm_host *host;
80 struct nlm_file *file;
81 __be32 rc = rpc_success;
82
83 dprintk("lockd: TEST4 called\n");
84 resp->cookie = argp->cookie;
85
86 /* Obtain client and file */
87 if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
88 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
89
90 /* Now check for conflicting locks */
91 resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
92 if (resp->status == nlm_drop_reply)
93 rc = rpc_drop_reply;
94 else
95 dprintk("lockd: TEST4 status %d\n", ntohl(resp->status));
96
97 nlmsvc_release_host(host);
98 nlm_release_file(file);
99 return rc;
100 }
101
102 static __be32
nlm4svc_proc_test(struct svc_rqst * rqstp)103 nlm4svc_proc_test(struct svc_rqst *rqstp)
104 {
105 return __nlm4svc_proc_test(rqstp, rqstp->rq_resp);
106 }
107
108 static __be32
__nlm4svc_proc_lock(struct svc_rqst * rqstp,struct nlm_res * resp)109 __nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_res *resp)
110 {
111 struct nlm_args *argp = rqstp->rq_argp;
112 struct nlm_host *host;
113 struct nlm_file *file;
114 __be32 rc = rpc_success;
115
116 dprintk("lockd: LOCK called\n");
117
118 resp->cookie = argp->cookie;
119
120 /* Obtain client and file */
121 if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
122 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
123
124 #if 0
125 /* If supplied state doesn't match current state, we assume it's
126 * an old request that time-warped somehow. Any error return would
127 * do in this case because it's irrelevant anyway.
128 *
129 * NB: We don't retrieve the remote host's state yet.
130 */
131 if (host->h_nsmstate && host->h_nsmstate != argp->state) {
132 resp->status = nlm_lck_denied_nolocks;
133 } else
134 #endif
135
136 /* Now try to lock the file */
137 resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
138 argp->block, &argp->cookie,
139 argp->reclaim);
140 if (resp->status == nlm_drop_reply)
141 rc = rpc_drop_reply;
142 else
143 dprintk("lockd: LOCK status %d\n", ntohl(resp->status));
144
145 nlmsvc_release_host(host);
146 nlm_release_file(file);
147 return rc;
148 }
149
150 static __be32
nlm4svc_proc_lock(struct svc_rqst * rqstp)151 nlm4svc_proc_lock(struct svc_rqst *rqstp)
152 {
153 return __nlm4svc_proc_lock(rqstp, rqstp->rq_resp);
154 }
155
156 static __be32
__nlm4svc_proc_cancel(struct svc_rqst * rqstp,struct nlm_res * resp)157 __nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_res *resp)
158 {
159 struct nlm_args *argp = rqstp->rq_argp;
160 struct nlm_host *host;
161 struct nlm_file *file;
162
163 dprintk("lockd: CANCEL called\n");
164
165 resp->cookie = argp->cookie;
166
167 /* Don't accept requests during grace period */
168 if (locks_in_grace(SVC_NET(rqstp))) {
169 resp->status = nlm_lck_denied_grace_period;
170 return rpc_success;
171 }
172
173 /* Obtain client and file */
174 if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
175 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
176
177 /* Try to cancel request. */
178 resp->status = nlmsvc_cancel_blocked(SVC_NET(rqstp), file, &argp->lock);
179
180 dprintk("lockd: CANCEL status %d\n", ntohl(resp->status));
181 nlmsvc_release_host(host);
182 nlm_release_file(file);
183 return rpc_success;
184 }
185
186 static __be32
nlm4svc_proc_cancel(struct svc_rqst * rqstp)187 nlm4svc_proc_cancel(struct svc_rqst *rqstp)
188 {
189 return __nlm4svc_proc_cancel(rqstp, rqstp->rq_resp);
190 }
191
192 /*
193 * UNLOCK: release a lock
194 */
195 static __be32
__nlm4svc_proc_unlock(struct svc_rqst * rqstp,struct nlm_res * resp)196 __nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_res *resp)
197 {
198 struct nlm_args *argp = rqstp->rq_argp;
199 struct nlm_host *host;
200 struct nlm_file *file;
201
202 dprintk("lockd: UNLOCK called\n");
203
204 resp->cookie = argp->cookie;
205
206 /* Don't accept new lock requests during grace period */
207 if (locks_in_grace(SVC_NET(rqstp))) {
208 resp->status = nlm_lck_denied_grace_period;
209 return rpc_success;
210 }
211
212 /* Obtain client and file */
213 if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
214 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
215
216 /* Now try to remove the lock */
217 resp->status = nlmsvc_unlock(SVC_NET(rqstp), file, &argp->lock);
218
219 dprintk("lockd: UNLOCK status %d\n", ntohl(resp->status));
220 nlmsvc_release_host(host);
221 nlm_release_file(file);
222 return rpc_success;
223 }
224
225 static __be32
nlm4svc_proc_unlock(struct svc_rqst * rqstp)226 nlm4svc_proc_unlock(struct svc_rqst *rqstp)
227 {
228 return __nlm4svc_proc_unlock(rqstp, rqstp->rq_resp);
229 }
230
231 /*
232 * GRANTED: A server calls us to tell that a process' lock request
233 * was granted
234 */
235 static __be32
__nlm4svc_proc_granted(struct svc_rqst * rqstp,struct nlm_res * resp)236 __nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_res *resp)
237 {
238 struct nlm_args *argp = rqstp->rq_argp;
239
240 resp->cookie = argp->cookie;
241
242 dprintk("lockd: GRANTED called\n");
243 resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
244 dprintk("lockd: GRANTED status %d\n", ntohl(resp->status));
245 return rpc_success;
246 }
247
248 static __be32
nlm4svc_proc_granted(struct svc_rqst * rqstp)249 nlm4svc_proc_granted(struct svc_rqst *rqstp)
250 {
251 return __nlm4svc_proc_granted(rqstp, rqstp->rq_resp);
252 }
253
254 /*
255 * This is the generic lockd callback for async RPC calls
256 */
nlm4svc_callback_exit(struct rpc_task * task,void * data)257 static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
258 {
259 dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
260 -task->tk_status);
261 }
262
nlm4svc_callback_release(void * data)263 static void nlm4svc_callback_release(void *data)
264 {
265 nlmsvc_release_call(data);
266 }
267
268 static const struct rpc_call_ops nlm4svc_callback_ops = {
269 .rpc_call_done = nlm4svc_callback_exit,
270 .rpc_release = nlm4svc_callback_release,
271 };
272
273 /*
274 * `Async' versions of the above service routines. They aren't really,
275 * because we send the callback before the reply proper. I hope this
276 * doesn't break any clients.
277 */
nlm4svc_callback(struct svc_rqst * rqstp,u32 proc,__be32 (* func)(struct svc_rqst *,struct nlm_res *))278 static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc,
279 __be32 (*func)(struct svc_rqst *, struct nlm_res *))
280 {
281 struct nlm_args *argp = rqstp->rq_argp;
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 nlmsvc_release_host(host);
294 if (call == NULL)
295 return rpc_system_err;
296
297 stat = func(rqstp, &call->a_res);
298 if (stat != 0) {
299 nlmsvc_release_call(call);
300 return stat;
301 }
302
303 call->a_flags = RPC_TASK_ASYNC;
304 if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
305 return rpc_system_err;
306 return rpc_success;
307 }
308
nlm4svc_proc_test_msg(struct svc_rqst * rqstp)309 static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp)
310 {
311 dprintk("lockd: TEST_MSG called\n");
312 return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, __nlm4svc_proc_test);
313 }
314
nlm4svc_proc_lock_msg(struct svc_rqst * rqstp)315 static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp)
316 {
317 dprintk("lockd: LOCK_MSG called\n");
318 return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, __nlm4svc_proc_lock);
319 }
320
nlm4svc_proc_cancel_msg(struct svc_rqst * rqstp)321 static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp)
322 {
323 dprintk("lockd: CANCEL_MSG called\n");
324 return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, __nlm4svc_proc_cancel);
325 }
326
nlm4svc_proc_unlock_msg(struct svc_rqst * rqstp)327 static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp)
328 {
329 dprintk("lockd: UNLOCK_MSG called\n");
330 return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, __nlm4svc_proc_unlock);
331 }
332
nlm4svc_proc_granted_msg(struct svc_rqst * rqstp)333 static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp)
334 {
335 dprintk("lockd: GRANTED_MSG called\n");
336 return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, __nlm4svc_proc_granted);
337 }
338
339 /*
340 * SHARE: create a DOS share or alter existing share.
341 */
342 static __be32
nlm4svc_proc_share(struct svc_rqst * rqstp)343 nlm4svc_proc_share(struct svc_rqst *rqstp)
344 {
345 struct nlm_args *argp = rqstp->rq_argp;
346 struct nlm_res *resp = rqstp->rq_resp;
347 struct nlm_host *host;
348 struct nlm_file *file;
349
350 dprintk("lockd: SHARE called\n");
351
352 resp->cookie = argp->cookie;
353
354 /* Don't accept new lock requests during grace period */
355 if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
356 resp->status = nlm_lck_denied_grace_period;
357 return rpc_success;
358 }
359
360 /* Obtain client and file */
361 if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
362 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
363
364 /* Now try to create the share */
365 resp->status = nlmsvc_share_file(host, file, argp);
366
367 dprintk("lockd: SHARE status %d\n", ntohl(resp->status));
368 nlmsvc_release_host(host);
369 nlm_release_file(file);
370 return rpc_success;
371 }
372
373 /*
374 * UNSHARE: Release a DOS share.
375 */
376 static __be32
nlm4svc_proc_unshare(struct svc_rqst * rqstp)377 nlm4svc_proc_unshare(struct svc_rqst *rqstp)
378 {
379 struct nlm_args *argp = rqstp->rq_argp;
380 struct nlm_res *resp = rqstp->rq_resp;
381 struct nlm_host *host;
382 struct nlm_file *file;
383
384 dprintk("lockd: UNSHARE called\n");
385
386 resp->cookie = argp->cookie;
387
388 /* Don't accept requests during grace period */
389 if (locks_in_grace(SVC_NET(rqstp))) {
390 resp->status = nlm_lck_denied_grace_period;
391 return rpc_success;
392 }
393
394 /* Obtain client and file */
395 if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
396 return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
397
398 /* Now try to lock the file */
399 resp->status = nlmsvc_unshare_file(host, file, argp);
400
401 dprintk("lockd: UNSHARE status %d\n", ntohl(resp->status));
402 nlmsvc_release_host(host);
403 nlm_release_file(file);
404 return rpc_success;
405 }
406
407 /*
408 * NM_LOCK: Create an unmonitored lock
409 */
410 static __be32
nlm4svc_proc_nm_lock(struct svc_rqst * rqstp)411 nlm4svc_proc_nm_lock(struct svc_rqst *rqstp)
412 {
413 struct nlm_args *argp = rqstp->rq_argp;
414
415 dprintk("lockd: NM_LOCK called\n");
416
417 argp->monitor = 0; /* just clean the monitor flag */
418 return nlm4svc_proc_lock(rqstp);
419 }
420
421 /*
422 * FREE_ALL: Release all locks and shares held by client
423 */
424 static __be32
nlm4svc_proc_free_all(struct svc_rqst * rqstp)425 nlm4svc_proc_free_all(struct svc_rqst *rqstp)
426 {
427 struct nlm_args *argp = rqstp->rq_argp;
428 struct nlm_host *host;
429
430 /* Obtain client */
431 if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
432 return rpc_success;
433
434 nlmsvc_free_host_resources(host);
435 nlmsvc_release_host(host);
436 return rpc_success;
437 }
438
439 /*
440 * SM_NOTIFY: private callback from statd (not part of official NLM proto)
441 */
442 static __be32
nlm4svc_proc_sm_notify(struct svc_rqst * rqstp)443 nlm4svc_proc_sm_notify(struct svc_rqst *rqstp)
444 {
445 struct nlm_reboot *argp = rqstp->rq_argp;
446
447 dprintk("lockd: SM_NOTIFY called\n");
448
449 if (!nlm_privileged_requester(rqstp)) {
450 char buf[RPC_MAX_ADDRBUFLEN];
451 printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
452 svc_print_addr(rqstp, buf, sizeof(buf)));
453 return rpc_system_err;
454 }
455
456 nlm_host_rebooted(SVC_NET(rqstp), argp);
457 return rpc_success;
458 }
459
460 /*
461 * client sent a GRANTED_RES, let's remove the associated block
462 */
463 static __be32
nlm4svc_proc_granted_res(struct svc_rqst * rqstp)464 nlm4svc_proc_granted_res(struct svc_rqst *rqstp)
465 {
466 struct nlm_res *argp = rqstp->rq_argp;
467
468 if (!nlmsvc_ops)
469 return rpc_success;
470
471 dprintk("lockd: GRANTED_RES called\n");
472
473 nlmsvc_grant_reply(&argp->cookie, argp->status);
474 return rpc_success;
475 }
476
477
478 /*
479 * NLM Server procedures.
480 */
481
482 #define nlm4svc_encode_norep nlm4svc_encode_void
483 #define nlm4svc_decode_norep nlm4svc_decode_void
484 #define nlm4svc_decode_testres nlm4svc_decode_void
485 #define nlm4svc_decode_lockres nlm4svc_decode_void
486 #define nlm4svc_decode_unlockres nlm4svc_decode_void
487 #define nlm4svc_decode_cancelres nlm4svc_decode_void
488 #define nlm4svc_decode_grantedres nlm4svc_decode_void
489
490 #define nlm4svc_proc_none nlm4svc_proc_null
491 #define nlm4svc_proc_test_res nlm4svc_proc_null
492 #define nlm4svc_proc_lock_res nlm4svc_proc_null
493 #define nlm4svc_proc_cancel_res nlm4svc_proc_null
494 #define nlm4svc_proc_unlock_res nlm4svc_proc_null
495
496 struct nlm_void { int dummy; };
497
498 #define PROC(name, xargt, xrest, argt, rest, respsize) \
499 { .pc_func = nlm4svc_proc_##name, \
500 .pc_decode = nlm4svc_decode_##xargt, \
501 .pc_encode = nlm4svc_encode_##xrest, \
502 .pc_release = NULL, \
503 .pc_argsize = sizeof(struct nlm_##argt), \
504 .pc_ressize = sizeof(struct nlm_##rest), \
505 .pc_xdrressize = respsize, \
506 }
507 #define Ck (1+XDR_QUADLEN(NLM_MAXCOOKIELEN)) /* cookie */
508 #define No (1+1024/4) /* netobj */
509 #define St 1 /* status */
510 #define Rg 4 /* range (offset + length) */
511 const struct svc_procedure nlmsvc_procedures4[] = {
512 PROC(null, void, void, void, void, 1),
513 PROC(test, testargs, testres, args, res, Ck+St+2+No+Rg),
514 PROC(lock, lockargs, res, args, res, Ck+St),
515 PROC(cancel, cancargs, res, args, res, Ck+St),
516 PROC(unlock, unlockargs, res, args, res, Ck+St),
517 PROC(granted, testargs, res, args, res, Ck+St),
518 PROC(test_msg, testargs, norep, args, void, 1),
519 PROC(lock_msg, lockargs, norep, args, void, 1),
520 PROC(cancel_msg, cancargs, norep, args, void, 1),
521 PROC(unlock_msg, unlockargs, norep, args, void, 1),
522 PROC(granted_msg, testargs, norep, args, void, 1),
523 PROC(test_res, testres, norep, res, void, 1),
524 PROC(lock_res, lockres, norep, res, void, 1),
525 PROC(cancel_res, cancelres, norep, res, void, 1),
526 PROC(unlock_res, unlockres, norep, res, void, 1),
527 PROC(granted_res, res, norep, res, void, 1),
528 /* statd callback */
529 PROC(sm_notify, reboot, void, reboot, void, 1),
530 PROC(none, void, void, void, void, 0),
531 PROC(none, void, void, void, void, 0),
532 PROC(none, void, void, void, void, 0),
533 PROC(share, shareargs, shareres, args, res, Ck+St+1),
534 PROC(unshare, shareargs, shareres, args, res, Ck+St+1),
535 PROC(nm_lock, lockargs, res, args, res, Ck+St),
536 PROC(free_all, notify, void, args, void, 1),
537
538 };
539