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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/fs/lockd/svc.c
4 *
5 * This is the central lockd service.
6 *
7 * FIXME: Separate the lockd NFS server functionality from the lockd NFS
8 * client functionality. Oh why didn't Sun create two separate
9 * services in the first place?
10 *
11 * Authors: Olaf Kirch (okir@monad.swb.de)
12 *
13 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
14 */
15
16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/sysctl.h>
19#include <linux/moduleparam.h>
20
21#include <linux/sched/signal.h>
22#include <linux/errno.h>
23#include <linux/in.h>
24#include <linux/uio.h>
25#include <linux/smp.h>
26#include <linux/mutex.h>
27#include <linux/freezer.h>
28#include <linux/inetdevice.h>
29
30#include <linux/sunrpc/types.h>
31#include <linux/sunrpc/stats.h>
32#include <linux/sunrpc/clnt.h>
33#include <linux/sunrpc/svc.h>
34#include <linux/sunrpc/svcsock.h>
35#include <linux/sunrpc/svc_xprt.h>
36#include <net/ip.h>
37#include <net/addrconf.h>
38#include <net/ipv6.h>
39#include <linux/lockd/lockd.h>
40#include <linux/nfs.h>
41
42#include "netns.h"
43#include "procfs.h"
44
45#define NLMDBG_FACILITY NLMDBG_SVC
46#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
47
48static struct svc_program nlmsvc_program;
49
50const struct nlmsvc_binding *nlmsvc_ops;
51EXPORT_SYMBOL_GPL(nlmsvc_ops);
52
53static DEFINE_MUTEX(nlmsvc_mutex);
54static unsigned int nlmsvc_users;
55static struct svc_serv *nlmsvc_serv;
56unsigned long nlmsvc_timeout;
57
58static void nlmsvc_request_retry(struct timer_list *tl)
59{
60 svc_wake_up(nlmsvc_serv);
61}
62DEFINE_TIMER(nlmsvc_retry, nlmsvc_request_retry);
63
64unsigned int lockd_net_id;
65
66/*
67 * These can be set at insmod time (useful for NFS as root filesystem),
68 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
69 */
70static unsigned long nlm_grace_period;
71static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
72static int nlm_udpport, nlm_tcpport;
73
74/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
75static unsigned int nlm_max_connections = 1024;
76
77/*
78 * Constants needed for the sysctl interface.
79 */
80static const unsigned long nlm_grace_period_min = 0;
81static const unsigned long nlm_grace_period_max = 240;
82static const unsigned long nlm_timeout_min = 3;
83static const unsigned long nlm_timeout_max = 20;
84
85#ifdef CONFIG_SYSCTL
86static const int nlm_port_min = 0, nlm_port_max = 65535;
87static struct ctl_table_header * nlm_sysctl_table;
88#endif
89
90static unsigned long get_lockd_grace_period(void)
91{
92 /* Note: nlm_timeout should always be nonzero */
93 if (nlm_grace_period)
94 return roundup(nlm_grace_period, nlm_timeout) * HZ;
95 else
96 return nlm_timeout * 5 * HZ;
97}
98
99static void grace_ender(struct work_struct *grace)
100{
101 struct delayed_work *dwork = to_delayed_work(grace);
102 struct lockd_net *ln = container_of(dwork, struct lockd_net,
103 grace_period_end);
104
105 locks_end_grace(&ln->lockd_manager);
106}
107
108static void set_grace_period(struct net *net)
109{
110 unsigned long grace_period = get_lockd_grace_period();
111 struct lockd_net *ln = net_generic(net, lockd_net_id);
112
113 locks_start_grace(net, &ln->lockd_manager);
114 cancel_delayed_work_sync(&ln->grace_period_end);
115 schedule_delayed_work(&ln->grace_period_end, grace_period);
116}
117
118/*
119 * This is the lockd kernel thread
120 */
121static int
122lockd(void *vrqstp)
123{
124 struct svc_rqst *rqstp = vrqstp;
125 struct net *net = &init_net;
126 struct lockd_net *ln = net_generic(net, lockd_net_id);
127
128 /* try_to_freeze() is called from svc_recv() */
129 set_freezable();
130
131 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
132
133 /*
134 * The main request loop. We don't terminate until the last
135 * NFS mount or NFS daemon has gone away.
136 */
137 while (!svc_thread_should_stop(rqstp)) {
138 /* update sv_maxconn if it has changed */
139 rqstp->rq_server->sv_maxconn = nlm_max_connections;
140
141 nlmsvc_retry_blocked(rqstp);
142 svc_recv(rqstp);
143 }
144 if (nlmsvc_ops)
145 nlmsvc_invalidate_all();
146 nlm_shutdown_hosts();
147 cancel_delayed_work_sync(&ln->grace_period_end);
148 locks_end_grace(&ln->lockd_manager);
149
150 dprintk("lockd_down: service stopped\n");
151
152 svc_exit_thread(rqstp);
153 return 0;
154}
155
156static int create_lockd_listener(struct svc_serv *serv, const char *name,
157 struct net *net, const int family,
158 const unsigned short port,
159 const struct cred *cred)
160{
161 struct svc_xprt *xprt;
162
163 xprt = svc_find_xprt(serv, name, net, family, 0);
164 if (xprt == NULL)
165 return svc_xprt_create(serv, name, net, family, port,
166 SVC_SOCK_DEFAULTS, cred);
167 svc_xprt_put(xprt);
168 return 0;
169}
170
171static int create_lockd_family(struct svc_serv *serv, struct net *net,
172 const int family, const struct cred *cred)
173{
174 int err;
175
176 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport,
177 cred);
178 if (err < 0)
179 return err;
180
181 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport,
182 cred);
183}
184
185/*
186 * Ensure there are active UDP and TCP listeners for lockd.
187 *
188 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
189 * local services (such as rpc.statd) still require UDP, and
190 * some NFS servers do not yet support NLM over TCP.
191 *
192 * Returns zero if all listeners are available; otherwise a
193 * negative errno value is returned.
194 */
195static int make_socks(struct svc_serv *serv, struct net *net,
196 const struct cred *cred)
197{
198 static int warned;
199 int err;
200
201 err = create_lockd_family(serv, net, PF_INET, cred);
202 if (err < 0)
203 goto out_err;
204
205 err = create_lockd_family(serv, net, PF_INET6, cred);
206 if (err < 0 && err != -EAFNOSUPPORT)
207 goto out_err;
208
209 warned = 0;
210 return 0;
211
212out_err:
213 if (warned++ == 0)
214 printk(KERN_WARNING
215 "lockd_up: makesock failed, error=%d\n", err);
216 svc_xprt_destroy_all(serv, net);
217 svc_rpcb_cleanup(serv, net);
218 return err;
219}
220
221static int lockd_up_net(struct svc_serv *serv, struct net *net,
222 const struct cred *cred)
223{
224 struct lockd_net *ln = net_generic(net, lockd_net_id);
225 int error;
226
227 if (ln->nlmsvc_users++)
228 return 0;
229
230 error = svc_bind(serv, net);
231 if (error)
232 goto err_bind;
233
234 error = make_socks(serv, net, cred);
235 if (error < 0)
236 goto err_bind;
237 set_grace_period(net);
238 dprintk("%s: per-net data created; net=%x\n", __func__, net->ns.inum);
239 return 0;
240
241err_bind:
242 ln->nlmsvc_users--;
243 return error;
244}
245
246static void lockd_down_net(struct svc_serv *serv, struct net *net)
247{
248 struct lockd_net *ln = net_generic(net, lockd_net_id);
249
250 if (ln->nlmsvc_users) {
251 if (--ln->nlmsvc_users == 0) {
252 nlm_shutdown_hosts_net(net);
253 cancel_delayed_work_sync(&ln->grace_period_end);
254 locks_end_grace(&ln->lockd_manager);
255 svc_xprt_destroy_all(serv, net);
256 svc_rpcb_cleanup(serv, net);
257 }
258 } else {
259 pr_err("%s: no users! net=%x\n",
260 __func__, net->ns.inum);
261 BUG();
262 }
263}
264
265static int lockd_inetaddr_event(struct notifier_block *this,
266 unsigned long event, void *ptr)
267{
268 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
269 struct sockaddr_in sin;
270
271 if (event != NETDEV_DOWN)
272 goto out;
273
274 if (nlmsvc_serv) {
275 dprintk("lockd_inetaddr_event: removed %pI4\n",
276 &ifa->ifa_local);
277 sin.sin_family = AF_INET;
278 sin.sin_addr.s_addr = ifa->ifa_local;
279 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin);
280 }
281
282out:
283 return NOTIFY_DONE;
284}
285
286static struct notifier_block lockd_inetaddr_notifier = {
287 .notifier_call = lockd_inetaddr_event,
288};
289
290#if IS_ENABLED(CONFIG_IPV6)
291static int lockd_inet6addr_event(struct notifier_block *this,
292 unsigned long event, void *ptr)
293{
294 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
295 struct sockaddr_in6 sin6;
296
297 if (event != NETDEV_DOWN)
298 goto out;
299
300 if (nlmsvc_serv) {
301 dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
302 sin6.sin6_family = AF_INET6;
303 sin6.sin6_addr = ifa->addr;
304 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
305 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
306 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin6);
307 }
308
309out:
310 return NOTIFY_DONE;
311}
312
313static struct notifier_block lockd_inet6addr_notifier = {
314 .notifier_call = lockd_inet6addr_event,
315};
316#endif
317
318static int lockd_get(void)
319{
320 struct svc_serv *serv;
321 int error;
322
323 if (nlmsvc_serv) {
324 nlmsvc_users++;
325 return 0;
326 }
327
328 /*
329 * Sanity check: if there's no pid,
330 * we should be the first user ...
331 */
332 if (nlmsvc_users)
333 printk(KERN_WARNING
334 "lockd_up: no pid, %d users??\n", nlmsvc_users);
335
336 if (!nlm_timeout)
337 nlm_timeout = LOCKD_DFLT_TIMEO;
338 nlmsvc_timeout = nlm_timeout * HZ;
339
340 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, lockd);
341 if (!serv) {
342 printk(KERN_WARNING "lockd_up: create service failed\n");
343 return -ENOMEM;
344 }
345
346 serv->sv_maxconn = nlm_max_connections;
347 error = svc_set_num_threads(serv, NULL, 1);
348 if (error < 0) {
349 svc_destroy(&serv);
350 return error;
351 }
352
353 nlmsvc_serv = serv;
354 register_inetaddr_notifier(&lockd_inetaddr_notifier);
355#if IS_ENABLED(CONFIG_IPV6)
356 register_inet6addr_notifier(&lockd_inet6addr_notifier);
357#endif
358 dprintk("lockd_up: service created\n");
359 nlmsvc_users++;
360 return 0;
361}
362
363static void lockd_put(void)
364{
365 if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
366 return;
367 if (--nlmsvc_users)
368 return;
369
370 unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
371#if IS_ENABLED(CONFIG_IPV6)
372 unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
373#endif
374
375 svc_set_num_threads(nlmsvc_serv, NULL, 0);
376 timer_delete_sync(&nlmsvc_retry);
377 svc_destroy(&nlmsvc_serv);
378 dprintk("lockd_down: service destroyed\n");
379}
380
381/*
382 * Bring up the lockd process if it's not already up.
383 */
384int lockd_up(struct net *net, const struct cred *cred)
385{
386 int error;
387
388 mutex_lock(&nlmsvc_mutex);
389
390 error = lockd_get();
391 if (error)
392 goto err;
393
394 error = lockd_up_net(nlmsvc_serv, net, cred);
395 if (error < 0) {
396 lockd_put();
397 goto err;
398 }
399
400err:
401 mutex_unlock(&nlmsvc_mutex);
402 return error;
403}
404EXPORT_SYMBOL_GPL(lockd_up);
405
406/*
407 * Decrement the user count and bring down lockd if we're the last.
408 */
409void
410lockd_down(struct net *net)
411{
412 mutex_lock(&nlmsvc_mutex);
413 lockd_down_net(nlmsvc_serv, net);
414 lockd_put();
415 mutex_unlock(&nlmsvc_mutex);
416}
417EXPORT_SYMBOL_GPL(lockd_down);
418
419#ifdef CONFIG_SYSCTL
420
421/*
422 * Sysctl parameters (same as module parameters, different interface).
423 */
424
425static struct ctl_table nlm_sysctls[] = {
426 {
427 .procname = "nlm_grace_period",
428 .data = &nlm_grace_period,
429 .maxlen = sizeof(unsigned long),
430 .mode = 0644,
431 .proc_handler = proc_doulongvec_minmax,
432 .extra1 = (unsigned long *) &nlm_grace_period_min,
433 .extra2 = (unsigned long *) &nlm_grace_period_max,
434 },
435 {
436 .procname = "nlm_timeout",
437 .data = &nlm_timeout,
438 .maxlen = sizeof(unsigned long),
439 .mode = 0644,
440 .proc_handler = proc_doulongvec_minmax,
441 .extra1 = (unsigned long *) &nlm_timeout_min,
442 .extra2 = (unsigned long *) &nlm_timeout_max,
443 },
444 {
445 .procname = "nlm_udpport",
446 .data = &nlm_udpport,
447 .maxlen = sizeof(int),
448 .mode = 0644,
449 .proc_handler = proc_dointvec_minmax,
450 .extra1 = (int *) &nlm_port_min,
451 .extra2 = (int *) &nlm_port_max,
452 },
453 {
454 .procname = "nlm_tcpport",
455 .data = &nlm_tcpport,
456 .maxlen = sizeof(int),
457 .mode = 0644,
458 .proc_handler = proc_dointvec_minmax,
459 .extra1 = (int *) &nlm_port_min,
460 .extra2 = (int *) &nlm_port_max,
461 },
462 {
463 .procname = "nsm_use_hostnames",
464 .data = &nsm_use_hostnames,
465 .maxlen = sizeof(bool),
466 .mode = 0644,
467 .proc_handler = proc_dobool,
468 },
469 {
470 .procname = "nsm_local_state",
471 .data = &nsm_local_state,
472 .maxlen = sizeof(int),
473 .mode = 0644,
474 .proc_handler = proc_dointvec,
475 },
476};
477
478#endif /* CONFIG_SYSCTL */
479
480/*
481 * Module (and sysfs) parameters.
482 */
483
484#define param_set_min_max(name, type, which_strtol, min, max) \
485static int param_set_##name(const char *val, const struct kernel_param *kp) \
486{ \
487 char *endp; \
488 __typeof__(type) num = which_strtol(val, &endp, 0); \
489 if (endp == val || *endp || num < (min) || num > (max)) \
490 return -EINVAL; \
491 *((type *) kp->arg) = num; \
492 return 0; \
493}
494
495static inline int is_callback(u32 proc)
496{
497 return proc == NLMPROC_GRANTED
498 || proc == NLMPROC_GRANTED_MSG
499 || proc == NLMPROC_TEST_RES
500 || proc == NLMPROC_LOCK_RES
501 || proc == NLMPROC_CANCEL_RES
502 || proc == NLMPROC_UNLOCK_RES
503 || proc == NLMPROC_NSM_NOTIFY;
504}
505
506
507static enum svc_auth_status lockd_authenticate(struct svc_rqst *rqstp)
508{
509 rqstp->rq_client = NULL;
510 switch (rqstp->rq_authop->flavour) {
511 case RPC_AUTH_NULL:
512 case RPC_AUTH_UNIX:
513 rqstp->rq_auth_stat = rpc_auth_ok;
514 if (rqstp->rq_proc == 0)
515 return SVC_OK;
516 if (is_callback(rqstp->rq_proc)) {
517 /* Leave it to individual procedures to
518 * call nlmsvc_lookup_host(rqstp)
519 */
520 return SVC_OK;
521 }
522 return svc_set_client(rqstp);
523 }
524 rqstp->rq_auth_stat = rpc_autherr_badcred;
525 return SVC_DENIED;
526}
527
528
529param_set_min_max(port, int, simple_strtol, 0, 65535)
530param_set_min_max(grace_period, unsigned long, simple_strtoul,
531 nlm_grace_period_min, nlm_grace_period_max)
532param_set_min_max(timeout, unsigned long, simple_strtoul,
533 nlm_timeout_min, nlm_timeout_max)
534
535MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
536MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
537MODULE_LICENSE("GPL");
538
539module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
540 &nlm_grace_period, 0644);
541module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
542 &nlm_timeout, 0644);
543module_param_call(nlm_udpport, param_set_port, param_get_int,
544 &nlm_udpport, 0644);
545module_param_call(nlm_tcpport, param_set_port, param_get_int,
546 &nlm_tcpport, 0644);
547module_param(nsm_use_hostnames, bool, 0644);
548module_param(nlm_max_connections, uint, 0644);
549
550static int lockd_init_net(struct net *net)
551{
552 struct lockd_net *ln = net_generic(net, lockd_net_id);
553
554 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
555 INIT_LIST_HEAD(&ln->lockd_manager.list);
556 ln->lockd_manager.block_opens = false;
557 INIT_LIST_HEAD(&ln->nsm_handles);
558 return 0;
559}
560
561static void lockd_exit_net(struct net *net)
562{
563 struct lockd_net *ln = net_generic(net, lockd_net_id);
564
565 WARN_ONCE(!list_empty(&ln->lockd_manager.list),
566 "net %x %s: lockd_manager.list is not empty\n",
567 net->ns.inum, __func__);
568 WARN_ONCE(!list_empty(&ln->nsm_handles),
569 "net %x %s: nsm_handles list is not empty\n",
570 net->ns.inum, __func__);
571 WARN_ONCE(delayed_work_pending(&ln->grace_period_end),
572 "net %x %s: grace_period_end was not cancelled\n",
573 net->ns.inum, __func__);
574}
575
576static struct pernet_operations lockd_net_ops = {
577 .init = lockd_init_net,
578 .exit = lockd_exit_net,
579 .id = &lockd_net_id,
580 .size = sizeof(struct lockd_net),
581};
582
583
584/*
585 * Initialising and terminating the module.
586 */
587
588static int __init init_nlm(void)
589{
590 int err;
591
592#ifdef CONFIG_SYSCTL
593 err = -ENOMEM;
594 nlm_sysctl_table = register_sysctl("fs/nfs", nlm_sysctls);
595 if (nlm_sysctl_table == NULL)
596 goto err_sysctl;
597#endif
598 err = register_pernet_subsys(&lockd_net_ops);
599 if (err)
600 goto err_pernet;
601
602 err = lockd_create_procfs();
603 if (err)
604 goto err_procfs;
605
606 return 0;
607
608err_procfs:
609 unregister_pernet_subsys(&lockd_net_ops);
610err_pernet:
611#ifdef CONFIG_SYSCTL
612 unregister_sysctl_table(nlm_sysctl_table);
613err_sysctl:
614#endif
615 return err;
616}
617
618static void __exit exit_nlm(void)
619{
620 /* FIXME: delete all NLM clients */
621 nlm_shutdown_hosts();
622 lockd_remove_procfs();
623 unregister_pernet_subsys(&lockd_net_ops);
624#ifdef CONFIG_SYSCTL
625 unregister_sysctl_table(nlm_sysctl_table);
626#endif
627}
628
629module_init(init_nlm);
630module_exit(exit_nlm);
631
632/**
633 * nlmsvc_dispatch - Process an NLM Request
634 * @rqstp: incoming request
635 *
636 * Return values:
637 * %0: Processing complete; do not send a Reply
638 * %1: Processing complete; send Reply in rqstp->rq_res
639 */
640static int nlmsvc_dispatch(struct svc_rqst *rqstp)
641{
642 const struct svc_procedure *procp = rqstp->rq_procinfo;
643 __be32 *statp = rqstp->rq_accept_statp;
644
645 if (!procp->pc_decode(rqstp, &rqstp->rq_arg_stream))
646 goto out_decode_err;
647
648 *statp = procp->pc_func(rqstp);
649 if (*statp == rpc_drop_reply)
650 return 0;
651 if (*statp != rpc_success)
652 return 1;
653
654 if (!procp->pc_encode(rqstp, &rqstp->rq_res_stream))
655 goto out_encode_err;
656
657 return 1;
658
659out_decode_err:
660 *statp = rpc_garbage_args;
661 return 1;
662
663out_encode_err:
664 *statp = rpc_system_err;
665 return 1;
666}
667
668/*
669 * Define NLM program and procedures
670 */
671static DEFINE_PER_CPU_ALIGNED(unsigned long, nlmsvc_version1_count[17]);
672static const struct svc_version nlmsvc_version1 = {
673 .vs_vers = 1,
674 .vs_nproc = 17,
675 .vs_proc = nlmsvc_procedures,
676 .vs_count = nlmsvc_version1_count,
677 .vs_dispatch = nlmsvc_dispatch,
678 .vs_xdrsize = NLMSVC_XDRSIZE,
679};
680
681static DEFINE_PER_CPU_ALIGNED(unsigned long,
682 nlmsvc_version3_count[ARRAY_SIZE(nlmsvc_procedures)]);
683static const struct svc_version nlmsvc_version3 = {
684 .vs_vers = 3,
685 .vs_nproc = ARRAY_SIZE(nlmsvc_procedures),
686 .vs_proc = nlmsvc_procedures,
687 .vs_count = nlmsvc_version3_count,
688 .vs_dispatch = nlmsvc_dispatch,
689 .vs_xdrsize = NLMSVC_XDRSIZE,
690};
691
692#ifdef CONFIG_LOCKD_V4
693static DEFINE_PER_CPU_ALIGNED(unsigned long,
694 nlmsvc_version4_count[ARRAY_SIZE(nlmsvc_procedures4)]);
695static const struct svc_version nlmsvc_version4 = {
696 .vs_vers = 4,
697 .vs_nproc = ARRAY_SIZE(nlmsvc_procedures4),
698 .vs_proc = nlmsvc_procedures4,
699 .vs_count = nlmsvc_version4_count,
700 .vs_dispatch = nlmsvc_dispatch,
701 .vs_xdrsize = NLMSVC_XDRSIZE,
702};
703#endif
704
705static const struct svc_version *nlmsvc_version[] = {
706 [1] = &nlmsvc_version1,
707 [3] = &nlmsvc_version3,
708#ifdef CONFIG_LOCKD_V4
709 [4] = &nlmsvc_version4,
710#endif
711};
712
713static struct svc_stat nlmsvc_stats;
714
715#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
716static struct svc_program nlmsvc_program = {
717 .pg_prog = NLM_PROGRAM, /* program number */
718 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
719 .pg_vers = nlmsvc_version, /* version table */
720 .pg_name = "lockd", /* service name */
721 .pg_class = "nfsd", /* share authentication with nfsd */
722 .pg_stats = &nlmsvc_stats, /* stats table */
723 .pg_authenticate = &lockd_authenticate, /* export authentication */
724 .pg_init_request = svc_generic_init_request,
725 .pg_rpcbind_set = svc_generic_rpcbind_set,
726};
1/*
2 * linux/fs/lockd/svc.c
3 *
4 * This is the central lockd service.
5 *
6 * FIXME: Separate the lockd NFS server functionality from the lockd NFS
7 * client functionality. Oh why didn't Sun create two separate
8 * services in the first place?
9 *
10 * Authors: Olaf Kirch (okir@monad.swb.de)
11 *
12 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
13 */
14
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/sysctl.h>
18#include <linux/moduleparam.h>
19
20#include <linux/sched.h>
21#include <linux/errno.h>
22#include <linux/in.h>
23#include <linux/uio.h>
24#include <linux/smp.h>
25#include <linux/mutex.h>
26#include <linux/kthread.h>
27#include <linux/freezer.h>
28
29#include <linux/sunrpc/types.h>
30#include <linux/sunrpc/stats.h>
31#include <linux/sunrpc/clnt.h>
32#include <linux/sunrpc/svc.h>
33#include <linux/sunrpc/svcsock.h>
34#include <net/ip.h>
35#include <linux/lockd/lockd.h>
36#include <linux/nfs.h>
37
38#include "netns.h"
39
40#define NLMDBG_FACILITY NLMDBG_SVC
41#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
42#define ALLOWED_SIGS (sigmask(SIGKILL))
43
44static struct svc_program nlmsvc_program;
45
46struct nlmsvc_binding * nlmsvc_ops;
47EXPORT_SYMBOL_GPL(nlmsvc_ops);
48
49static DEFINE_MUTEX(nlmsvc_mutex);
50static unsigned int nlmsvc_users;
51static struct task_struct *nlmsvc_task;
52static struct svc_rqst *nlmsvc_rqst;
53unsigned long nlmsvc_timeout;
54
55int lockd_net_id;
56
57/*
58 * These can be set at insmod time (useful for NFS as root filesystem),
59 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
60 */
61static unsigned long nlm_grace_period;
62static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
63static int nlm_udpport, nlm_tcpport;
64
65/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
66static unsigned int nlm_max_connections = 1024;
67
68/*
69 * Constants needed for the sysctl interface.
70 */
71static const unsigned long nlm_grace_period_min = 0;
72static const unsigned long nlm_grace_period_max = 240;
73static const unsigned long nlm_timeout_min = 3;
74static const unsigned long nlm_timeout_max = 20;
75static const int nlm_port_min = 0, nlm_port_max = 65535;
76
77#ifdef CONFIG_SYSCTL
78static struct ctl_table_header * nlm_sysctl_table;
79#endif
80
81static unsigned long get_lockd_grace_period(void)
82{
83 /* Note: nlm_timeout should always be nonzero */
84 if (nlm_grace_period)
85 return roundup(nlm_grace_period, nlm_timeout) * HZ;
86 else
87 return nlm_timeout * 5 * HZ;
88}
89
90static void grace_ender(struct work_struct *grace)
91{
92 struct delayed_work *dwork = container_of(grace, struct delayed_work,
93 work);
94 struct lockd_net *ln = container_of(dwork, struct lockd_net,
95 grace_period_end);
96
97 locks_end_grace(&ln->lockd_manager);
98}
99
100static void set_grace_period(struct net *net)
101{
102 unsigned long grace_period = get_lockd_grace_period();
103 struct lockd_net *ln = net_generic(net, lockd_net_id);
104
105 locks_start_grace(net, &ln->lockd_manager);
106 cancel_delayed_work_sync(&ln->grace_period_end);
107 schedule_delayed_work(&ln->grace_period_end, grace_period);
108}
109
110static void restart_grace(void)
111{
112 if (nlmsvc_ops) {
113 struct net *net = &init_net;
114 struct lockd_net *ln = net_generic(net, lockd_net_id);
115
116 cancel_delayed_work_sync(&ln->grace_period_end);
117 locks_end_grace(&ln->lockd_manager);
118 nlmsvc_invalidate_all();
119 set_grace_period(net);
120 }
121}
122
123/*
124 * This is the lockd kernel thread
125 */
126static int
127lockd(void *vrqstp)
128{
129 int err = 0;
130 struct svc_rqst *rqstp = vrqstp;
131
132 /* try_to_freeze() is called from svc_recv() */
133 set_freezable();
134
135 /* Allow SIGKILL to tell lockd to drop all of its locks */
136 allow_signal(SIGKILL);
137
138 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
139
140 if (!nlm_timeout)
141 nlm_timeout = LOCKD_DFLT_TIMEO;
142 nlmsvc_timeout = nlm_timeout * HZ;
143
144 /*
145 * The main request loop. We don't terminate until the last
146 * NFS mount or NFS daemon has gone away.
147 */
148 while (!kthread_should_stop()) {
149 long timeout = MAX_SCHEDULE_TIMEOUT;
150 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
151
152 /* update sv_maxconn if it has changed */
153 rqstp->rq_server->sv_maxconn = nlm_max_connections;
154
155 if (signalled()) {
156 flush_signals(current);
157 restart_grace();
158 continue;
159 }
160
161 timeout = nlmsvc_retry_blocked();
162
163 /*
164 * Find a socket with data available and call its
165 * recvfrom routine.
166 */
167 err = svc_recv(rqstp, timeout);
168 if (err == -EAGAIN || err == -EINTR)
169 continue;
170 dprintk("lockd: request from %s\n",
171 svc_print_addr(rqstp, buf, sizeof(buf)));
172
173 svc_process(rqstp);
174 }
175 flush_signals(current);
176 if (nlmsvc_ops)
177 nlmsvc_invalidate_all();
178 nlm_shutdown_hosts();
179 return 0;
180}
181
182static int create_lockd_listener(struct svc_serv *serv, const char *name,
183 struct net *net, const int family,
184 const unsigned short port)
185{
186 struct svc_xprt *xprt;
187
188 xprt = svc_find_xprt(serv, name, net, family, 0);
189 if (xprt == NULL)
190 return svc_create_xprt(serv, name, net, family, port,
191 SVC_SOCK_DEFAULTS);
192 svc_xprt_put(xprt);
193 return 0;
194}
195
196static int create_lockd_family(struct svc_serv *serv, struct net *net,
197 const int family)
198{
199 int err;
200
201 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport);
202 if (err < 0)
203 return err;
204
205 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport);
206}
207
208/*
209 * Ensure there are active UDP and TCP listeners for lockd.
210 *
211 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
212 * local services (such as rpc.statd) still require UDP, and
213 * some NFS servers do not yet support NLM over TCP.
214 *
215 * Returns zero if all listeners are available; otherwise a
216 * negative errno value is returned.
217 */
218static int make_socks(struct svc_serv *serv, struct net *net)
219{
220 static int warned;
221 int err;
222
223 err = create_lockd_family(serv, net, PF_INET);
224 if (err < 0)
225 goto out_err;
226
227 err = create_lockd_family(serv, net, PF_INET6);
228 if (err < 0 && err != -EAFNOSUPPORT)
229 goto out_err;
230
231 warned = 0;
232 return 0;
233
234out_err:
235 if (warned++ == 0)
236 printk(KERN_WARNING
237 "lockd_up: makesock failed, error=%d\n", err);
238 svc_shutdown_net(serv, net);
239 return err;
240}
241
242static int lockd_up_net(struct svc_serv *serv, struct net *net)
243{
244 struct lockd_net *ln = net_generic(net, lockd_net_id);
245 int error;
246
247 if (ln->nlmsvc_users++)
248 return 0;
249
250 error = svc_bind(serv, net);
251 if (error)
252 goto err_bind;
253
254 error = make_socks(serv, net);
255 if (error < 0)
256 goto err_socks;
257 set_grace_period(net);
258 dprintk("lockd_up_net: per-net data created; net=%p\n", net);
259 return 0;
260
261err_socks:
262 svc_rpcb_cleanup(serv, net);
263err_bind:
264 ln->nlmsvc_users--;
265 return error;
266}
267
268static void lockd_down_net(struct svc_serv *serv, struct net *net)
269{
270 struct lockd_net *ln = net_generic(net, lockd_net_id);
271
272 if (ln->nlmsvc_users) {
273 if (--ln->nlmsvc_users == 0) {
274 nlm_shutdown_hosts_net(net);
275 cancel_delayed_work_sync(&ln->grace_period_end);
276 locks_end_grace(&ln->lockd_manager);
277 svc_shutdown_net(serv, net);
278 dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net);
279 }
280 } else {
281 printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n",
282 nlmsvc_task, net);
283 BUG();
284 }
285}
286
287static int lockd_start_svc(struct svc_serv *serv)
288{
289 int error;
290
291 if (nlmsvc_rqst)
292 return 0;
293
294 /*
295 * Create the kernel thread and wait for it to start.
296 */
297 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
298 if (IS_ERR(nlmsvc_rqst)) {
299 error = PTR_ERR(nlmsvc_rqst);
300 printk(KERN_WARNING
301 "lockd_up: svc_rqst allocation failed, error=%d\n",
302 error);
303 goto out_rqst;
304 }
305
306 svc_sock_update_bufs(serv);
307 serv->sv_maxconn = nlm_max_connections;
308
309 nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, "%s", serv->sv_name);
310 if (IS_ERR(nlmsvc_task)) {
311 error = PTR_ERR(nlmsvc_task);
312 printk(KERN_WARNING
313 "lockd_up: kthread_run failed, error=%d\n", error);
314 goto out_task;
315 }
316 dprintk("lockd_up: service started\n");
317 return 0;
318
319out_task:
320 svc_exit_thread(nlmsvc_rqst);
321 nlmsvc_task = NULL;
322out_rqst:
323 nlmsvc_rqst = NULL;
324 return error;
325}
326
327static struct svc_serv *lockd_create_svc(void)
328{
329 struct svc_serv *serv;
330
331 /*
332 * Check whether we're already up and running.
333 */
334 if (nlmsvc_rqst) {
335 /*
336 * Note: increase service usage, because later in case of error
337 * svc_destroy() will be called.
338 */
339 svc_get(nlmsvc_rqst->rq_server);
340 return nlmsvc_rqst->rq_server;
341 }
342
343 /*
344 * Sanity check: if there's no pid,
345 * we should be the first user ...
346 */
347 if (nlmsvc_users)
348 printk(KERN_WARNING
349 "lockd_up: no pid, %d users??\n", nlmsvc_users);
350
351 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
352 if (!serv) {
353 printk(KERN_WARNING "lockd_up: create service failed\n");
354 return ERR_PTR(-ENOMEM);
355 }
356 dprintk("lockd_up: service created\n");
357 return serv;
358}
359
360/*
361 * Bring up the lockd process if it's not already up.
362 */
363int lockd_up(struct net *net)
364{
365 struct svc_serv *serv;
366 int error;
367
368 mutex_lock(&nlmsvc_mutex);
369
370 serv = lockd_create_svc();
371 if (IS_ERR(serv)) {
372 error = PTR_ERR(serv);
373 goto err_create;
374 }
375
376 error = lockd_up_net(serv, net);
377 if (error < 0)
378 goto err_net;
379
380 error = lockd_start_svc(serv);
381 if (error < 0)
382 goto err_start;
383
384 nlmsvc_users++;
385 /*
386 * Note: svc_serv structures have an initial use count of 1,
387 * so we exit through here on both success and failure.
388 */
389err_net:
390 svc_destroy(serv);
391err_create:
392 mutex_unlock(&nlmsvc_mutex);
393 return error;
394
395err_start:
396 lockd_down_net(serv, net);
397 goto err_net;
398}
399EXPORT_SYMBOL_GPL(lockd_up);
400
401/*
402 * Decrement the user count and bring down lockd if we're the last.
403 */
404void
405lockd_down(struct net *net)
406{
407 mutex_lock(&nlmsvc_mutex);
408 lockd_down_net(nlmsvc_rqst->rq_server, net);
409 if (nlmsvc_users) {
410 if (--nlmsvc_users)
411 goto out;
412 } else {
413 printk(KERN_ERR "lockd_down: no users! task=%p\n",
414 nlmsvc_task);
415 BUG();
416 }
417
418 if (!nlmsvc_task) {
419 printk(KERN_ERR "lockd_down: no lockd running.\n");
420 BUG();
421 }
422 kthread_stop(nlmsvc_task);
423 dprintk("lockd_down: service stopped\n");
424 svc_exit_thread(nlmsvc_rqst);
425 dprintk("lockd_down: service destroyed\n");
426 nlmsvc_task = NULL;
427 nlmsvc_rqst = NULL;
428out:
429 mutex_unlock(&nlmsvc_mutex);
430}
431EXPORT_SYMBOL_GPL(lockd_down);
432
433#ifdef CONFIG_SYSCTL
434
435/*
436 * Sysctl parameters (same as module parameters, different interface).
437 */
438
439static ctl_table nlm_sysctls[] = {
440 {
441 .procname = "nlm_grace_period",
442 .data = &nlm_grace_period,
443 .maxlen = sizeof(unsigned long),
444 .mode = 0644,
445 .proc_handler = proc_doulongvec_minmax,
446 .extra1 = (unsigned long *) &nlm_grace_period_min,
447 .extra2 = (unsigned long *) &nlm_grace_period_max,
448 },
449 {
450 .procname = "nlm_timeout",
451 .data = &nlm_timeout,
452 .maxlen = sizeof(unsigned long),
453 .mode = 0644,
454 .proc_handler = proc_doulongvec_minmax,
455 .extra1 = (unsigned long *) &nlm_timeout_min,
456 .extra2 = (unsigned long *) &nlm_timeout_max,
457 },
458 {
459 .procname = "nlm_udpport",
460 .data = &nlm_udpport,
461 .maxlen = sizeof(int),
462 .mode = 0644,
463 .proc_handler = proc_dointvec_minmax,
464 .extra1 = (int *) &nlm_port_min,
465 .extra2 = (int *) &nlm_port_max,
466 },
467 {
468 .procname = "nlm_tcpport",
469 .data = &nlm_tcpport,
470 .maxlen = sizeof(int),
471 .mode = 0644,
472 .proc_handler = proc_dointvec_minmax,
473 .extra1 = (int *) &nlm_port_min,
474 .extra2 = (int *) &nlm_port_max,
475 },
476 {
477 .procname = "nsm_use_hostnames",
478 .data = &nsm_use_hostnames,
479 .maxlen = sizeof(int),
480 .mode = 0644,
481 .proc_handler = proc_dointvec,
482 },
483 {
484 .procname = "nsm_local_state",
485 .data = &nsm_local_state,
486 .maxlen = sizeof(int),
487 .mode = 0644,
488 .proc_handler = proc_dointvec,
489 },
490 { }
491};
492
493static ctl_table nlm_sysctl_dir[] = {
494 {
495 .procname = "nfs",
496 .mode = 0555,
497 .child = nlm_sysctls,
498 },
499 { }
500};
501
502static ctl_table nlm_sysctl_root[] = {
503 {
504 .procname = "fs",
505 .mode = 0555,
506 .child = nlm_sysctl_dir,
507 },
508 { }
509};
510
511#endif /* CONFIG_SYSCTL */
512
513/*
514 * Module (and sysfs) parameters.
515 */
516
517#define param_set_min_max(name, type, which_strtol, min, max) \
518static int param_set_##name(const char *val, struct kernel_param *kp) \
519{ \
520 char *endp; \
521 __typeof__(type) num = which_strtol(val, &endp, 0); \
522 if (endp == val || *endp || num < (min) || num > (max)) \
523 return -EINVAL; \
524 *((type *) kp->arg) = num; \
525 return 0; \
526}
527
528static inline int is_callback(u32 proc)
529{
530 return proc == NLMPROC_GRANTED
531 || proc == NLMPROC_GRANTED_MSG
532 || proc == NLMPROC_TEST_RES
533 || proc == NLMPROC_LOCK_RES
534 || proc == NLMPROC_CANCEL_RES
535 || proc == NLMPROC_UNLOCK_RES
536 || proc == NLMPROC_NSM_NOTIFY;
537}
538
539
540static int lockd_authenticate(struct svc_rqst *rqstp)
541{
542 rqstp->rq_client = NULL;
543 switch (rqstp->rq_authop->flavour) {
544 case RPC_AUTH_NULL:
545 case RPC_AUTH_UNIX:
546 if (rqstp->rq_proc == 0)
547 return SVC_OK;
548 if (is_callback(rqstp->rq_proc)) {
549 /* Leave it to individual procedures to
550 * call nlmsvc_lookup_host(rqstp)
551 */
552 return SVC_OK;
553 }
554 return svc_set_client(rqstp);
555 }
556 return SVC_DENIED;
557}
558
559
560param_set_min_max(port, int, simple_strtol, 0, 65535)
561param_set_min_max(grace_period, unsigned long, simple_strtoul,
562 nlm_grace_period_min, nlm_grace_period_max)
563param_set_min_max(timeout, unsigned long, simple_strtoul,
564 nlm_timeout_min, nlm_timeout_max)
565
566MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
567MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
568MODULE_LICENSE("GPL");
569
570module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
571 &nlm_grace_period, 0644);
572module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
573 &nlm_timeout, 0644);
574module_param_call(nlm_udpport, param_set_port, param_get_int,
575 &nlm_udpport, 0644);
576module_param_call(nlm_tcpport, param_set_port, param_get_int,
577 &nlm_tcpport, 0644);
578module_param(nsm_use_hostnames, bool, 0644);
579module_param(nlm_max_connections, uint, 0644);
580
581static int lockd_init_net(struct net *net)
582{
583 struct lockd_net *ln = net_generic(net, lockd_net_id);
584
585 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
586 INIT_LIST_HEAD(&ln->grace_list);
587 spin_lock_init(&ln->nsm_clnt_lock);
588 return 0;
589}
590
591static void lockd_exit_net(struct net *net)
592{
593}
594
595static struct pernet_operations lockd_net_ops = {
596 .init = lockd_init_net,
597 .exit = lockd_exit_net,
598 .id = &lockd_net_id,
599 .size = sizeof(struct lockd_net),
600};
601
602
603/*
604 * Initialising and terminating the module.
605 */
606
607static int __init init_nlm(void)
608{
609 int err;
610
611#ifdef CONFIG_SYSCTL
612 err = -ENOMEM;
613 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
614 if (nlm_sysctl_table == NULL)
615 goto err_sysctl;
616#endif
617 err = register_pernet_subsys(&lockd_net_ops);
618 if (err)
619 goto err_pernet;
620 return 0;
621
622err_pernet:
623#ifdef CONFIG_SYSCTL
624 unregister_sysctl_table(nlm_sysctl_table);
625#endif
626err_sysctl:
627 return err;
628}
629
630static void __exit exit_nlm(void)
631{
632 /* FIXME: delete all NLM clients */
633 nlm_shutdown_hosts();
634 unregister_pernet_subsys(&lockd_net_ops);
635#ifdef CONFIG_SYSCTL
636 unregister_sysctl_table(nlm_sysctl_table);
637#endif
638}
639
640module_init(init_nlm);
641module_exit(exit_nlm);
642
643/*
644 * Define NLM program and procedures
645 */
646static struct svc_version nlmsvc_version1 = {
647 .vs_vers = 1,
648 .vs_nproc = 17,
649 .vs_proc = nlmsvc_procedures,
650 .vs_xdrsize = NLMSVC_XDRSIZE,
651};
652static struct svc_version nlmsvc_version3 = {
653 .vs_vers = 3,
654 .vs_nproc = 24,
655 .vs_proc = nlmsvc_procedures,
656 .vs_xdrsize = NLMSVC_XDRSIZE,
657};
658#ifdef CONFIG_LOCKD_V4
659static struct svc_version nlmsvc_version4 = {
660 .vs_vers = 4,
661 .vs_nproc = 24,
662 .vs_proc = nlmsvc_procedures4,
663 .vs_xdrsize = NLMSVC_XDRSIZE,
664};
665#endif
666static struct svc_version * nlmsvc_version[] = {
667 [1] = &nlmsvc_version1,
668 [3] = &nlmsvc_version3,
669#ifdef CONFIG_LOCKD_V4
670 [4] = &nlmsvc_version4,
671#endif
672};
673
674static struct svc_stat nlmsvc_stats;
675
676#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
677static struct svc_program nlmsvc_program = {
678 .pg_prog = NLM_PROGRAM, /* program number */
679 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
680 .pg_vers = nlmsvc_version, /* version table */
681 .pg_name = "lockd", /* service name */
682 .pg_class = "nfsd", /* share authentication with nfsd */
683 .pg_stats = &nlmsvc_stats, /* stats table */
684 .pg_authenticate = &lockd_authenticate /* export authentication */
685};