Loading...
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/kthread.h>
28#include <linux/freezer.h>
29#include <linux/inetdevice.h>
30
31#include <linux/sunrpc/types.h>
32#include <linux/sunrpc/stats.h>
33#include <linux/sunrpc/clnt.h>
34#include <linux/sunrpc/svc.h>
35#include <linux/sunrpc/svcsock.h>
36#include <linux/sunrpc/svc_xprt.h>
37#include <net/ip.h>
38#include <net/addrconf.h>
39#include <net/ipv6.h>
40#include <linux/lockd/lockd.h>
41#include <linux/nfs.h>
42
43#include "netns.h"
44#include "procfs.h"
45
46#define NLMDBG_FACILITY NLMDBG_SVC
47#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
48#define ALLOWED_SIGS (sigmask(SIGKILL))
49
50static struct svc_program nlmsvc_program;
51
52const struct nlmsvc_binding *nlmsvc_ops;
53EXPORT_SYMBOL_GPL(nlmsvc_ops);
54
55static DEFINE_MUTEX(nlmsvc_mutex);
56static unsigned int nlmsvc_users;
57static struct svc_serv *nlmsvc_serv;
58unsigned long nlmsvc_timeout;
59
60unsigned int lockd_net_id;
61
62/*
63 * These can be set at insmod time (useful for NFS as root filesystem),
64 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
65 */
66static unsigned long nlm_grace_period;
67static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
68static int nlm_udpport, nlm_tcpport;
69
70/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
71static unsigned int nlm_max_connections = 1024;
72
73/*
74 * Constants needed for the sysctl interface.
75 */
76static const unsigned long nlm_grace_period_min = 0;
77static const unsigned long nlm_grace_period_max = 240;
78static const unsigned long nlm_timeout_min = 3;
79static const unsigned long nlm_timeout_max = 20;
80static const int nlm_port_min = 0, nlm_port_max = 65535;
81
82#ifdef CONFIG_SYSCTL
83static struct ctl_table_header * nlm_sysctl_table;
84#endif
85
86static unsigned long get_lockd_grace_period(void)
87{
88 /* Note: nlm_timeout should always be nonzero */
89 if (nlm_grace_period)
90 return roundup(nlm_grace_period, nlm_timeout) * HZ;
91 else
92 return nlm_timeout * 5 * HZ;
93}
94
95static void grace_ender(struct work_struct *grace)
96{
97 struct delayed_work *dwork = to_delayed_work(grace);
98 struct lockd_net *ln = container_of(dwork, struct lockd_net,
99 grace_period_end);
100
101 locks_end_grace(&ln->lockd_manager);
102}
103
104static void set_grace_period(struct net *net)
105{
106 unsigned long grace_period = get_lockd_grace_period();
107 struct lockd_net *ln = net_generic(net, lockd_net_id);
108
109 locks_start_grace(net, &ln->lockd_manager);
110 cancel_delayed_work_sync(&ln->grace_period_end);
111 schedule_delayed_work(&ln->grace_period_end, grace_period);
112}
113
114static void restart_grace(void)
115{
116 if (nlmsvc_ops) {
117 struct net *net = &init_net;
118 struct lockd_net *ln = net_generic(net, lockd_net_id);
119
120 cancel_delayed_work_sync(&ln->grace_period_end);
121 locks_end_grace(&ln->lockd_manager);
122 nlmsvc_invalidate_all();
123 set_grace_period(net);
124 }
125}
126
127/*
128 * This is the lockd kernel thread
129 */
130static int
131lockd(void *vrqstp)
132{
133 int err = 0;
134 struct svc_rqst *rqstp = vrqstp;
135 struct net *net = &init_net;
136 struct lockd_net *ln = net_generic(net, lockd_net_id);
137
138 /* try_to_freeze() is called from svc_recv() */
139 set_freezable();
140
141 /* Allow SIGKILL to tell lockd to drop all of its locks */
142 allow_signal(SIGKILL);
143
144 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
145
146 /*
147 * The main request loop. We don't terminate until the last
148 * NFS mount or NFS daemon has gone away.
149 */
150 while (!kthread_should_stop()) {
151 long timeout = MAX_SCHEDULE_TIMEOUT;
152 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
153
154 /* update sv_maxconn if it has changed */
155 rqstp->rq_server->sv_maxconn = nlm_max_connections;
156
157 if (signalled()) {
158 flush_signals(current);
159 restart_grace();
160 continue;
161 }
162
163 timeout = nlmsvc_retry_blocked();
164
165 /*
166 * Find a socket with data available and call its
167 * recvfrom routine.
168 */
169 err = svc_recv(rqstp, timeout);
170 if (err == -EAGAIN || err == -EINTR)
171 continue;
172 dprintk("lockd: request from %s\n",
173 svc_print_addr(rqstp, buf, sizeof(buf)));
174
175 svc_process(rqstp);
176 }
177 flush_signals(current);
178 if (nlmsvc_ops)
179 nlmsvc_invalidate_all();
180 nlm_shutdown_hosts();
181 cancel_delayed_work_sync(&ln->grace_period_end);
182 locks_end_grace(&ln->lockd_manager);
183
184 dprintk("lockd_down: service stopped\n");
185
186 svc_exit_thread(rqstp);
187 return 0;
188}
189
190static int create_lockd_listener(struct svc_serv *serv, const char *name,
191 struct net *net, const int family,
192 const unsigned short port,
193 const struct cred *cred)
194{
195 struct svc_xprt *xprt;
196
197 xprt = svc_find_xprt(serv, name, net, family, 0);
198 if (xprt == NULL)
199 return svc_xprt_create(serv, name, net, family, port,
200 SVC_SOCK_DEFAULTS, cred);
201 svc_xprt_put(xprt);
202 return 0;
203}
204
205static int create_lockd_family(struct svc_serv *serv, struct net *net,
206 const int family, const struct cred *cred)
207{
208 int err;
209
210 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport,
211 cred);
212 if (err < 0)
213 return err;
214
215 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport,
216 cred);
217}
218
219/*
220 * Ensure there are active UDP and TCP listeners for lockd.
221 *
222 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
223 * local services (such as rpc.statd) still require UDP, and
224 * some NFS servers do not yet support NLM over TCP.
225 *
226 * Returns zero if all listeners are available; otherwise a
227 * negative errno value is returned.
228 */
229static int make_socks(struct svc_serv *serv, struct net *net,
230 const struct cred *cred)
231{
232 static int warned;
233 int err;
234
235 err = create_lockd_family(serv, net, PF_INET, cred);
236 if (err < 0)
237 goto out_err;
238
239 err = create_lockd_family(serv, net, PF_INET6, cred);
240 if (err < 0 && err != -EAFNOSUPPORT)
241 goto out_err;
242
243 warned = 0;
244 return 0;
245
246out_err:
247 if (warned++ == 0)
248 printk(KERN_WARNING
249 "lockd_up: makesock failed, error=%d\n", err);
250 svc_xprt_destroy_all(serv, net);
251 svc_rpcb_cleanup(serv, net);
252 return err;
253}
254
255static int lockd_up_net(struct svc_serv *serv, struct net *net,
256 const struct cred *cred)
257{
258 struct lockd_net *ln = net_generic(net, lockd_net_id);
259 int error;
260
261 if (ln->nlmsvc_users++)
262 return 0;
263
264 error = svc_bind(serv, net);
265 if (error)
266 goto err_bind;
267
268 error = make_socks(serv, net, cred);
269 if (error < 0)
270 goto err_bind;
271 set_grace_period(net);
272 dprintk("%s: per-net data created; net=%x\n", __func__, net->ns.inum);
273 return 0;
274
275err_bind:
276 ln->nlmsvc_users--;
277 return error;
278}
279
280static void lockd_down_net(struct svc_serv *serv, struct net *net)
281{
282 struct lockd_net *ln = net_generic(net, lockd_net_id);
283
284 if (ln->nlmsvc_users) {
285 if (--ln->nlmsvc_users == 0) {
286 nlm_shutdown_hosts_net(net);
287 cancel_delayed_work_sync(&ln->grace_period_end);
288 locks_end_grace(&ln->lockd_manager);
289 svc_xprt_destroy_all(serv, net);
290 svc_rpcb_cleanup(serv, net);
291 }
292 } else {
293 pr_err("%s: no users! net=%x\n",
294 __func__, net->ns.inum);
295 BUG();
296 }
297}
298
299static int lockd_inetaddr_event(struct notifier_block *this,
300 unsigned long event, void *ptr)
301{
302 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
303 struct sockaddr_in sin;
304
305 if (event != NETDEV_DOWN)
306 goto out;
307
308 if (nlmsvc_serv) {
309 dprintk("lockd_inetaddr_event: removed %pI4\n",
310 &ifa->ifa_local);
311 sin.sin_family = AF_INET;
312 sin.sin_addr.s_addr = ifa->ifa_local;
313 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin);
314 }
315
316out:
317 return NOTIFY_DONE;
318}
319
320static struct notifier_block lockd_inetaddr_notifier = {
321 .notifier_call = lockd_inetaddr_event,
322};
323
324#if IS_ENABLED(CONFIG_IPV6)
325static int lockd_inet6addr_event(struct notifier_block *this,
326 unsigned long event, void *ptr)
327{
328 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
329 struct sockaddr_in6 sin6;
330
331 if (event != NETDEV_DOWN)
332 goto out;
333
334 if (nlmsvc_serv) {
335 dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
336 sin6.sin6_family = AF_INET6;
337 sin6.sin6_addr = ifa->addr;
338 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
339 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
340 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin6);
341 }
342
343out:
344 return NOTIFY_DONE;
345}
346
347static struct notifier_block lockd_inet6addr_notifier = {
348 .notifier_call = lockd_inet6addr_event,
349};
350#endif
351
352static int lockd_get(void)
353{
354 struct svc_serv *serv;
355 int error;
356
357 if (nlmsvc_serv) {
358 svc_get(nlmsvc_serv);
359 nlmsvc_users++;
360 return 0;
361 }
362
363 /*
364 * Sanity check: if there's no pid,
365 * we should be the first user ...
366 */
367 if (nlmsvc_users)
368 printk(KERN_WARNING
369 "lockd_up: no pid, %d users??\n", nlmsvc_users);
370
371 if (!nlm_timeout)
372 nlm_timeout = LOCKD_DFLT_TIMEO;
373 nlmsvc_timeout = nlm_timeout * HZ;
374
375 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, lockd);
376 if (!serv) {
377 printk(KERN_WARNING "lockd_up: create service failed\n");
378 return -ENOMEM;
379 }
380
381 serv->sv_maxconn = nlm_max_connections;
382 error = svc_set_num_threads(serv, NULL, 1);
383 /* The thread now holds the only reference */
384 svc_put(serv);
385 if (error < 0)
386 return error;
387
388 nlmsvc_serv = serv;
389 register_inetaddr_notifier(&lockd_inetaddr_notifier);
390#if IS_ENABLED(CONFIG_IPV6)
391 register_inet6addr_notifier(&lockd_inet6addr_notifier);
392#endif
393 dprintk("lockd_up: service created\n");
394 nlmsvc_users++;
395 return 0;
396}
397
398static void lockd_put(void)
399{
400 if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
401 return;
402 if (--nlmsvc_users)
403 return;
404
405 unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
406#if IS_ENABLED(CONFIG_IPV6)
407 unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
408#endif
409
410 svc_set_num_threads(nlmsvc_serv, NULL, 0);
411 nlmsvc_serv = NULL;
412 dprintk("lockd_down: service destroyed\n");
413}
414
415/*
416 * Bring up the lockd process if it's not already up.
417 */
418int lockd_up(struct net *net, const struct cred *cred)
419{
420 int error;
421
422 mutex_lock(&nlmsvc_mutex);
423
424 error = lockd_get();
425 if (error)
426 goto err;
427
428 error = lockd_up_net(nlmsvc_serv, net, cred);
429 if (error < 0) {
430 lockd_put();
431 goto err;
432 }
433
434err:
435 mutex_unlock(&nlmsvc_mutex);
436 return error;
437}
438EXPORT_SYMBOL_GPL(lockd_up);
439
440/*
441 * Decrement the user count and bring down lockd if we're the last.
442 */
443void
444lockd_down(struct net *net)
445{
446 mutex_lock(&nlmsvc_mutex);
447 lockd_down_net(nlmsvc_serv, net);
448 lockd_put();
449 mutex_unlock(&nlmsvc_mutex);
450}
451EXPORT_SYMBOL_GPL(lockd_down);
452
453#ifdef CONFIG_SYSCTL
454
455/*
456 * Sysctl parameters (same as module parameters, different interface).
457 */
458
459static struct ctl_table nlm_sysctls[] = {
460 {
461 .procname = "nlm_grace_period",
462 .data = &nlm_grace_period,
463 .maxlen = sizeof(unsigned long),
464 .mode = 0644,
465 .proc_handler = proc_doulongvec_minmax,
466 .extra1 = (unsigned long *) &nlm_grace_period_min,
467 .extra2 = (unsigned long *) &nlm_grace_period_max,
468 },
469 {
470 .procname = "nlm_timeout",
471 .data = &nlm_timeout,
472 .maxlen = sizeof(unsigned long),
473 .mode = 0644,
474 .proc_handler = proc_doulongvec_minmax,
475 .extra1 = (unsigned long *) &nlm_timeout_min,
476 .extra2 = (unsigned long *) &nlm_timeout_max,
477 },
478 {
479 .procname = "nlm_udpport",
480 .data = &nlm_udpport,
481 .maxlen = sizeof(int),
482 .mode = 0644,
483 .proc_handler = proc_dointvec_minmax,
484 .extra1 = (int *) &nlm_port_min,
485 .extra2 = (int *) &nlm_port_max,
486 },
487 {
488 .procname = "nlm_tcpport",
489 .data = &nlm_tcpport,
490 .maxlen = sizeof(int),
491 .mode = 0644,
492 .proc_handler = proc_dointvec_minmax,
493 .extra1 = (int *) &nlm_port_min,
494 .extra2 = (int *) &nlm_port_max,
495 },
496 {
497 .procname = "nsm_use_hostnames",
498 .data = &nsm_use_hostnames,
499 .maxlen = sizeof(int),
500 .mode = 0644,
501 .proc_handler = proc_dobool,
502 },
503 {
504 .procname = "nsm_local_state",
505 .data = &nsm_local_state,
506 .maxlen = sizeof(int),
507 .mode = 0644,
508 .proc_handler = proc_dointvec,
509 },
510 { }
511};
512
513static struct ctl_table nlm_sysctl_dir[] = {
514 {
515 .procname = "nfs",
516 .mode = 0555,
517 .child = nlm_sysctls,
518 },
519 { }
520};
521
522static struct ctl_table nlm_sysctl_root[] = {
523 {
524 .procname = "fs",
525 .mode = 0555,
526 .child = nlm_sysctl_dir,
527 },
528 { }
529};
530
531#endif /* CONFIG_SYSCTL */
532
533/*
534 * Module (and sysfs) parameters.
535 */
536
537#define param_set_min_max(name, type, which_strtol, min, max) \
538static int param_set_##name(const char *val, const struct kernel_param *kp) \
539{ \
540 char *endp; \
541 __typeof__(type) num = which_strtol(val, &endp, 0); \
542 if (endp == val || *endp || num < (min) || num > (max)) \
543 return -EINVAL; \
544 *((type *) kp->arg) = num; \
545 return 0; \
546}
547
548static inline int is_callback(u32 proc)
549{
550 return proc == NLMPROC_GRANTED
551 || proc == NLMPROC_GRANTED_MSG
552 || proc == NLMPROC_TEST_RES
553 || proc == NLMPROC_LOCK_RES
554 || proc == NLMPROC_CANCEL_RES
555 || proc == NLMPROC_UNLOCK_RES
556 || proc == NLMPROC_NSM_NOTIFY;
557}
558
559
560static int lockd_authenticate(struct svc_rqst *rqstp)
561{
562 rqstp->rq_client = NULL;
563 switch (rqstp->rq_authop->flavour) {
564 case RPC_AUTH_NULL:
565 case RPC_AUTH_UNIX:
566 rqstp->rq_auth_stat = rpc_auth_ok;
567 if (rqstp->rq_proc == 0)
568 return SVC_OK;
569 if (is_callback(rqstp->rq_proc)) {
570 /* Leave it to individual procedures to
571 * call nlmsvc_lookup_host(rqstp)
572 */
573 return SVC_OK;
574 }
575 return svc_set_client(rqstp);
576 }
577 rqstp->rq_auth_stat = rpc_autherr_badcred;
578 return SVC_DENIED;
579}
580
581
582param_set_min_max(port, int, simple_strtol, 0, 65535)
583param_set_min_max(grace_period, unsigned long, simple_strtoul,
584 nlm_grace_period_min, nlm_grace_period_max)
585param_set_min_max(timeout, unsigned long, simple_strtoul,
586 nlm_timeout_min, nlm_timeout_max)
587
588MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
589MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
590MODULE_LICENSE("GPL");
591
592module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
593 &nlm_grace_period, 0644);
594module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
595 &nlm_timeout, 0644);
596module_param_call(nlm_udpport, param_set_port, param_get_int,
597 &nlm_udpport, 0644);
598module_param_call(nlm_tcpport, param_set_port, param_get_int,
599 &nlm_tcpport, 0644);
600module_param(nsm_use_hostnames, bool, 0644);
601module_param(nlm_max_connections, uint, 0644);
602
603static int lockd_init_net(struct net *net)
604{
605 struct lockd_net *ln = net_generic(net, lockd_net_id);
606
607 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
608 INIT_LIST_HEAD(&ln->lockd_manager.list);
609 ln->lockd_manager.block_opens = false;
610 INIT_LIST_HEAD(&ln->nsm_handles);
611 return 0;
612}
613
614static void lockd_exit_net(struct net *net)
615{
616 struct lockd_net *ln = net_generic(net, lockd_net_id);
617
618 WARN_ONCE(!list_empty(&ln->lockd_manager.list),
619 "net %x %s: lockd_manager.list is not empty\n",
620 net->ns.inum, __func__);
621 WARN_ONCE(!list_empty(&ln->nsm_handles),
622 "net %x %s: nsm_handles list is not empty\n",
623 net->ns.inum, __func__);
624 WARN_ONCE(delayed_work_pending(&ln->grace_period_end),
625 "net %x %s: grace_period_end was not cancelled\n",
626 net->ns.inum, __func__);
627}
628
629static struct pernet_operations lockd_net_ops = {
630 .init = lockd_init_net,
631 .exit = lockd_exit_net,
632 .id = &lockd_net_id,
633 .size = sizeof(struct lockd_net),
634};
635
636
637/*
638 * Initialising and terminating the module.
639 */
640
641static int __init init_nlm(void)
642{
643 int err;
644
645#ifdef CONFIG_SYSCTL
646 err = -ENOMEM;
647 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
648 if (nlm_sysctl_table == NULL)
649 goto err_sysctl;
650#endif
651 err = register_pernet_subsys(&lockd_net_ops);
652 if (err)
653 goto err_pernet;
654
655 err = lockd_create_procfs();
656 if (err)
657 goto err_procfs;
658
659 return 0;
660
661err_procfs:
662 unregister_pernet_subsys(&lockd_net_ops);
663err_pernet:
664#ifdef CONFIG_SYSCTL
665 unregister_sysctl_table(nlm_sysctl_table);
666err_sysctl:
667#endif
668 return err;
669}
670
671static void __exit exit_nlm(void)
672{
673 /* FIXME: delete all NLM clients */
674 nlm_shutdown_hosts();
675 lockd_remove_procfs();
676 unregister_pernet_subsys(&lockd_net_ops);
677#ifdef CONFIG_SYSCTL
678 unregister_sysctl_table(nlm_sysctl_table);
679#endif
680}
681
682module_init(init_nlm);
683module_exit(exit_nlm);
684
685/**
686 * nlmsvc_dispatch - Process an NLM Request
687 * @rqstp: incoming request
688 * @statp: pointer to location of accept_stat field in RPC Reply buffer
689 *
690 * Return values:
691 * %0: Processing complete; do not send a Reply
692 * %1: Processing complete; send Reply in rqstp->rq_res
693 */
694static int nlmsvc_dispatch(struct svc_rqst *rqstp, __be32 *statp)
695{
696 const struct svc_procedure *procp = rqstp->rq_procinfo;
697
698 svcxdr_init_decode(rqstp);
699 if (!procp->pc_decode(rqstp, &rqstp->rq_arg_stream))
700 goto out_decode_err;
701
702 *statp = procp->pc_func(rqstp);
703 if (*statp == rpc_drop_reply)
704 return 0;
705 if (*statp != rpc_success)
706 return 1;
707
708 svcxdr_init_encode(rqstp);
709 if (!procp->pc_encode(rqstp, &rqstp->rq_res_stream))
710 goto out_encode_err;
711
712 return 1;
713
714out_decode_err:
715 *statp = rpc_garbage_args;
716 return 1;
717
718out_encode_err:
719 *statp = rpc_system_err;
720 return 1;
721}
722
723/*
724 * Define NLM program and procedures
725 */
726static unsigned int nlmsvc_version1_count[17];
727static const struct svc_version nlmsvc_version1 = {
728 .vs_vers = 1,
729 .vs_nproc = 17,
730 .vs_proc = nlmsvc_procedures,
731 .vs_count = nlmsvc_version1_count,
732 .vs_dispatch = nlmsvc_dispatch,
733 .vs_xdrsize = NLMSVC_XDRSIZE,
734};
735static unsigned int nlmsvc_version3_count[24];
736static const struct svc_version nlmsvc_version3 = {
737 .vs_vers = 3,
738 .vs_nproc = 24,
739 .vs_proc = nlmsvc_procedures,
740 .vs_count = nlmsvc_version3_count,
741 .vs_dispatch = nlmsvc_dispatch,
742 .vs_xdrsize = NLMSVC_XDRSIZE,
743};
744#ifdef CONFIG_LOCKD_V4
745static unsigned int nlmsvc_version4_count[24];
746static const struct svc_version nlmsvc_version4 = {
747 .vs_vers = 4,
748 .vs_nproc = 24,
749 .vs_proc = nlmsvc_procedures4,
750 .vs_count = nlmsvc_version4_count,
751 .vs_dispatch = nlmsvc_dispatch,
752 .vs_xdrsize = NLMSVC_XDRSIZE,
753};
754#endif
755static const struct svc_version *nlmsvc_version[] = {
756 [1] = &nlmsvc_version1,
757 [3] = &nlmsvc_version3,
758#ifdef CONFIG_LOCKD_V4
759 [4] = &nlmsvc_version4,
760#endif
761};
762
763static struct svc_stat nlmsvc_stats;
764
765#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
766static struct svc_program nlmsvc_program = {
767 .pg_prog = NLM_PROGRAM, /* program number */
768 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
769 .pg_vers = nlmsvc_version, /* version table */
770 .pg_name = "lockd", /* service name */
771 .pg_class = "nfsd", /* share authentication with nfsd */
772 .pg_stats = &nlmsvc_stats, /* stats table */
773 .pg_authenticate = &lockd_authenticate, /* export authentication */
774 .pg_init_request = svc_generic_init_request,
775 .pg_rpcbind_set = svc_generic_rpcbind_set,
776};
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 struct lock_manager lockd_manager = {
91};
92
93static void grace_ender(struct work_struct *not_used)
94{
95 locks_end_grace(&lockd_manager);
96}
97
98static DECLARE_DELAYED_WORK(grace_period_end, grace_ender);
99
100static void set_grace_period(void)
101{
102 unsigned long grace_period = get_lockd_grace_period();
103
104 locks_start_grace(&lockd_manager);
105 cancel_delayed_work_sync(&grace_period_end);
106 schedule_delayed_work(&grace_period_end, grace_period);
107}
108
109static void restart_grace(void)
110{
111 if (nlmsvc_ops) {
112 cancel_delayed_work_sync(&grace_period_end);
113 locks_end_grace(&lockd_manager);
114 nlmsvc_invalidate_all();
115 set_grace_period();
116 }
117}
118
119/*
120 * This is the lockd kernel thread
121 */
122static int
123lockd(void *vrqstp)
124{
125 int err = 0, preverr = 0;
126 struct svc_rqst *rqstp = vrqstp;
127
128 /* try_to_freeze() is called from svc_recv() */
129 set_freezable();
130
131 /* Allow SIGKILL to tell lockd to drop all of its locks */
132 allow_signal(SIGKILL);
133
134 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
135
136 if (!nlm_timeout)
137 nlm_timeout = LOCKD_DFLT_TIMEO;
138 nlmsvc_timeout = nlm_timeout * HZ;
139
140 set_grace_period();
141
142 /*
143 * The main request loop. We don't terminate until the last
144 * NFS mount or NFS daemon has gone away.
145 */
146 while (!kthread_should_stop()) {
147 long timeout = MAX_SCHEDULE_TIMEOUT;
148 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
149
150 /* update sv_maxconn if it has changed */
151 rqstp->rq_server->sv_maxconn = nlm_max_connections;
152
153 if (signalled()) {
154 flush_signals(current);
155 restart_grace();
156 continue;
157 }
158
159 timeout = nlmsvc_retry_blocked();
160
161 /*
162 * Find a socket with data available and call its
163 * recvfrom routine.
164 */
165 err = svc_recv(rqstp, timeout);
166 if (err == -EAGAIN || err == -EINTR) {
167 preverr = err;
168 continue;
169 }
170 if (err < 0) {
171 if (err != preverr) {
172 printk(KERN_WARNING "%s: unexpected error "
173 "from svc_recv (%d)\n", __func__, err);
174 preverr = err;
175 }
176 schedule_timeout_interruptible(HZ);
177 continue;
178 }
179 preverr = err;
180
181 dprintk("lockd: request from %s\n",
182 svc_print_addr(rqstp, buf, sizeof(buf)));
183
184 svc_process(rqstp);
185 }
186 flush_signals(current);
187 cancel_delayed_work_sync(&grace_period_end);
188 locks_end_grace(&lockd_manager);
189 if (nlmsvc_ops)
190 nlmsvc_invalidate_all();
191 nlm_shutdown_hosts();
192 return 0;
193}
194
195static int create_lockd_listener(struct svc_serv *serv, const char *name,
196 struct net *net, const int family,
197 const unsigned short port)
198{
199 struct svc_xprt *xprt;
200
201 xprt = svc_find_xprt(serv, name, net, family, 0);
202 if (xprt == NULL)
203 return svc_create_xprt(serv, name, net, family, port,
204 SVC_SOCK_DEFAULTS);
205 svc_xprt_put(xprt);
206 return 0;
207}
208
209static int create_lockd_family(struct svc_serv *serv, struct net *net,
210 const int family)
211{
212 int err;
213
214 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport);
215 if (err < 0)
216 return err;
217
218 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport);
219}
220
221/*
222 * Ensure there are active UDP and TCP listeners for lockd.
223 *
224 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
225 * local services (such as rpc.statd) still require UDP, and
226 * some NFS servers do not yet support NLM over TCP.
227 *
228 * Returns zero if all listeners are available; otherwise a
229 * negative errno value is returned.
230 */
231static int make_socks(struct svc_serv *serv, struct net *net)
232{
233 static int warned;
234 int err;
235
236 err = create_lockd_family(serv, net, PF_INET);
237 if (err < 0)
238 goto out_err;
239
240 err = create_lockd_family(serv, net, PF_INET6);
241 if (err < 0 && err != -EAFNOSUPPORT)
242 goto out_err;
243
244 warned = 0;
245 return 0;
246
247out_err:
248 if (warned++ == 0)
249 printk(KERN_WARNING
250 "lockd_up: makesock failed, error=%d\n", err);
251 return err;
252}
253
254static int lockd_up_net(struct svc_serv *serv, struct net *net)
255{
256 struct lockd_net *ln = net_generic(net, lockd_net_id);
257 int error;
258
259 if (ln->nlmsvc_users++)
260 return 0;
261
262 error = svc_bind(serv, net);
263 if (error)
264 goto err_bind;
265
266 error = make_socks(serv, net);
267 if (error < 0)
268 goto err_socks;
269 dprintk("lockd_up_net: per-net data created; net=%p\n", net);
270 return 0;
271
272err_socks:
273 svc_rpcb_cleanup(serv, net);
274err_bind:
275 ln->nlmsvc_users--;
276 return error;
277}
278
279static void lockd_down_net(struct svc_serv *serv, struct net *net)
280{
281 struct lockd_net *ln = net_generic(net, lockd_net_id);
282
283 if (ln->nlmsvc_users) {
284 if (--ln->nlmsvc_users == 0) {
285 nlm_shutdown_hosts_net(net);
286 svc_shutdown_net(serv, net);
287 dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net);
288 }
289 } else {
290 printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n",
291 nlmsvc_task, net);
292 BUG();
293 }
294}
295
296static int lockd_start_svc(struct svc_serv *serv)
297{
298 int error;
299
300 if (nlmsvc_rqst)
301 return 0;
302
303 /*
304 * Create the kernel thread and wait for it to start.
305 */
306 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
307 if (IS_ERR(nlmsvc_rqst)) {
308 error = PTR_ERR(nlmsvc_rqst);
309 printk(KERN_WARNING
310 "lockd_up: svc_rqst allocation failed, error=%d\n",
311 error);
312 goto out_rqst;
313 }
314
315 svc_sock_update_bufs(serv);
316 serv->sv_maxconn = nlm_max_connections;
317
318 nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
319 if (IS_ERR(nlmsvc_task)) {
320 error = PTR_ERR(nlmsvc_task);
321 printk(KERN_WARNING
322 "lockd_up: kthread_run failed, error=%d\n", error);
323 goto out_task;
324 }
325 dprintk("lockd_up: service started\n");
326 return 0;
327
328out_task:
329 svc_exit_thread(nlmsvc_rqst);
330 nlmsvc_task = NULL;
331out_rqst:
332 nlmsvc_rqst = NULL;
333 return error;
334}
335
336static struct svc_serv *lockd_create_svc(void)
337{
338 struct svc_serv *serv;
339
340 /*
341 * Check whether we're already up and running.
342 */
343 if (nlmsvc_rqst) {
344 /*
345 * Note: increase service usage, because later in case of error
346 * svc_destroy() will be called.
347 */
348 svc_get(nlmsvc_rqst->rq_server);
349 return nlmsvc_rqst->rq_server;
350 }
351
352 /*
353 * Sanity check: if there's no pid,
354 * we should be the first user ...
355 */
356 if (nlmsvc_users)
357 printk(KERN_WARNING
358 "lockd_up: no pid, %d users??\n", nlmsvc_users);
359
360 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
361 if (!serv) {
362 printk(KERN_WARNING "lockd_up: create service failed\n");
363 return ERR_PTR(-ENOMEM);
364 }
365 dprintk("lockd_up: service created\n");
366 return serv;
367}
368
369/*
370 * Bring up the lockd process if it's not already up.
371 */
372int lockd_up(struct net *net)
373{
374 struct svc_serv *serv;
375 int error;
376
377 mutex_lock(&nlmsvc_mutex);
378
379 serv = lockd_create_svc();
380 if (IS_ERR(serv)) {
381 error = PTR_ERR(serv);
382 goto err_create;
383 }
384
385 error = lockd_up_net(serv, net);
386 if (error < 0)
387 goto err_net;
388
389 error = lockd_start_svc(serv);
390 if (error < 0)
391 goto err_start;
392
393 nlmsvc_users++;
394 /*
395 * Note: svc_serv structures have an initial use count of 1,
396 * so we exit through here on both success and failure.
397 */
398err_net:
399 svc_destroy(serv);
400err_create:
401 mutex_unlock(&nlmsvc_mutex);
402 return error;
403
404err_start:
405 lockd_down_net(serv, net);
406 goto err_net;
407}
408EXPORT_SYMBOL_GPL(lockd_up);
409
410/*
411 * Decrement the user count and bring down lockd if we're the last.
412 */
413void
414lockd_down(struct net *net)
415{
416 mutex_lock(&nlmsvc_mutex);
417 lockd_down_net(nlmsvc_rqst->rq_server, net);
418 if (nlmsvc_users) {
419 if (--nlmsvc_users)
420 goto out;
421 } else {
422 printk(KERN_ERR "lockd_down: no users! task=%p\n",
423 nlmsvc_task);
424 BUG();
425 }
426
427 if (!nlmsvc_task) {
428 printk(KERN_ERR "lockd_down: no lockd running.\n");
429 BUG();
430 }
431 kthread_stop(nlmsvc_task);
432 dprintk("lockd_down: service stopped\n");
433 svc_exit_thread(nlmsvc_rqst);
434 dprintk("lockd_down: service destroyed\n");
435 nlmsvc_task = NULL;
436 nlmsvc_rqst = NULL;
437out:
438 mutex_unlock(&nlmsvc_mutex);
439}
440EXPORT_SYMBOL_GPL(lockd_down);
441
442#ifdef CONFIG_SYSCTL
443
444/*
445 * Sysctl parameters (same as module parameters, different interface).
446 */
447
448static ctl_table nlm_sysctls[] = {
449 {
450 .procname = "nlm_grace_period",
451 .data = &nlm_grace_period,
452 .maxlen = sizeof(unsigned long),
453 .mode = 0644,
454 .proc_handler = proc_doulongvec_minmax,
455 .extra1 = (unsigned long *) &nlm_grace_period_min,
456 .extra2 = (unsigned long *) &nlm_grace_period_max,
457 },
458 {
459 .procname = "nlm_timeout",
460 .data = &nlm_timeout,
461 .maxlen = sizeof(unsigned long),
462 .mode = 0644,
463 .proc_handler = proc_doulongvec_minmax,
464 .extra1 = (unsigned long *) &nlm_timeout_min,
465 .extra2 = (unsigned long *) &nlm_timeout_max,
466 },
467 {
468 .procname = "nlm_udpport",
469 .data = &nlm_udpport,
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 = "nlm_tcpport",
478 .data = &nlm_tcpport,
479 .maxlen = sizeof(int),
480 .mode = 0644,
481 .proc_handler = proc_dointvec_minmax,
482 .extra1 = (int *) &nlm_port_min,
483 .extra2 = (int *) &nlm_port_max,
484 },
485 {
486 .procname = "nsm_use_hostnames",
487 .data = &nsm_use_hostnames,
488 .maxlen = sizeof(int),
489 .mode = 0644,
490 .proc_handler = proc_dointvec,
491 },
492 {
493 .procname = "nsm_local_state",
494 .data = &nsm_local_state,
495 .maxlen = sizeof(int),
496 .mode = 0644,
497 .proc_handler = proc_dointvec,
498 },
499 { }
500};
501
502static ctl_table nlm_sysctl_dir[] = {
503 {
504 .procname = "nfs",
505 .mode = 0555,
506 .child = nlm_sysctls,
507 },
508 { }
509};
510
511static ctl_table nlm_sysctl_root[] = {
512 {
513 .procname = "fs",
514 .mode = 0555,
515 .child = nlm_sysctl_dir,
516 },
517 { }
518};
519
520#endif /* CONFIG_SYSCTL */
521
522/*
523 * Module (and sysfs) parameters.
524 */
525
526#define param_set_min_max(name, type, which_strtol, min, max) \
527static int param_set_##name(const char *val, struct kernel_param *kp) \
528{ \
529 char *endp; \
530 __typeof__(type) num = which_strtol(val, &endp, 0); \
531 if (endp == val || *endp || num < (min) || num > (max)) \
532 return -EINVAL; \
533 *((type *) kp->arg) = num; \
534 return 0; \
535}
536
537static inline int is_callback(u32 proc)
538{
539 return proc == NLMPROC_GRANTED
540 || proc == NLMPROC_GRANTED_MSG
541 || proc == NLMPROC_TEST_RES
542 || proc == NLMPROC_LOCK_RES
543 || proc == NLMPROC_CANCEL_RES
544 || proc == NLMPROC_UNLOCK_RES
545 || proc == NLMPROC_NSM_NOTIFY;
546}
547
548
549static int lockd_authenticate(struct svc_rqst *rqstp)
550{
551 rqstp->rq_client = NULL;
552 switch (rqstp->rq_authop->flavour) {
553 case RPC_AUTH_NULL:
554 case RPC_AUTH_UNIX:
555 if (rqstp->rq_proc == 0)
556 return SVC_OK;
557 if (is_callback(rqstp->rq_proc)) {
558 /* Leave it to individual procedures to
559 * call nlmsvc_lookup_host(rqstp)
560 */
561 return SVC_OK;
562 }
563 return svc_set_client(rqstp);
564 }
565 return SVC_DENIED;
566}
567
568
569param_set_min_max(port, int, simple_strtol, 0, 65535)
570param_set_min_max(grace_period, unsigned long, simple_strtoul,
571 nlm_grace_period_min, nlm_grace_period_max)
572param_set_min_max(timeout, unsigned long, simple_strtoul,
573 nlm_timeout_min, nlm_timeout_max)
574
575MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
576MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
577MODULE_LICENSE("GPL");
578
579module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
580 &nlm_grace_period, 0644);
581module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
582 &nlm_timeout, 0644);
583module_param_call(nlm_udpport, param_set_port, param_get_int,
584 &nlm_udpport, 0644);
585module_param_call(nlm_tcpport, param_set_port, param_get_int,
586 &nlm_tcpport, 0644);
587module_param(nsm_use_hostnames, bool, 0644);
588module_param(nlm_max_connections, uint, 0644);
589
590static int lockd_init_net(struct net *net)
591{
592 return 0;
593}
594
595static void lockd_exit_net(struct net *net)
596{
597}
598
599static struct pernet_operations lockd_net_ops = {
600 .init = lockd_init_net,
601 .exit = lockd_exit_net,
602 .id = &lockd_net_id,
603 .size = sizeof(struct lockd_net),
604};
605
606
607/*
608 * Initialising and terminating the module.
609 */
610
611static int __init init_nlm(void)
612{
613 int err;
614
615#ifdef CONFIG_SYSCTL
616 err = -ENOMEM;
617 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
618 if (nlm_sysctl_table == NULL)
619 goto err_sysctl;
620#endif
621 err = register_pernet_subsys(&lockd_net_ops);
622 if (err)
623 goto err_pernet;
624 return 0;
625
626err_pernet:
627#ifdef CONFIG_SYSCTL
628 unregister_sysctl_table(nlm_sysctl_table);
629#endif
630err_sysctl:
631 return err;
632}
633
634static void __exit exit_nlm(void)
635{
636 /* FIXME: delete all NLM clients */
637 nlm_shutdown_hosts();
638 unregister_pernet_subsys(&lockd_net_ops);
639#ifdef CONFIG_SYSCTL
640 unregister_sysctl_table(nlm_sysctl_table);
641#endif
642}
643
644module_init(init_nlm);
645module_exit(exit_nlm);
646
647/*
648 * Define NLM program and procedures
649 */
650static struct svc_version nlmsvc_version1 = {
651 .vs_vers = 1,
652 .vs_nproc = 17,
653 .vs_proc = nlmsvc_procedures,
654 .vs_xdrsize = NLMSVC_XDRSIZE,
655};
656static struct svc_version nlmsvc_version3 = {
657 .vs_vers = 3,
658 .vs_nproc = 24,
659 .vs_proc = nlmsvc_procedures,
660 .vs_xdrsize = NLMSVC_XDRSIZE,
661};
662#ifdef CONFIG_LOCKD_V4
663static struct svc_version nlmsvc_version4 = {
664 .vs_vers = 4,
665 .vs_nproc = 24,
666 .vs_proc = nlmsvc_procedures4,
667 .vs_xdrsize = NLMSVC_XDRSIZE,
668};
669#endif
670static struct svc_version * nlmsvc_version[] = {
671 [1] = &nlmsvc_version1,
672 [3] = &nlmsvc_version3,
673#ifdef CONFIG_LOCKD_V4
674 [4] = &nlmsvc_version4,
675#endif
676};
677
678static struct svc_stat nlmsvc_stats;
679
680#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
681static struct svc_program nlmsvc_program = {
682 .pg_prog = NLM_PROGRAM, /* program number */
683 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
684 .pg_vers = nlmsvc_version, /* version table */
685 .pg_name = "lockd", /* service name */
686 .pg_class = "nfsd", /* share authentication with nfsd */
687 .pg_stats = &nlmsvc_stats, /* stats table */
688 .pg_authenticate = &lockd_authenticate /* export authentication */
689};