1 // SPDX-License-Identifier: GPL-2.0-only
5 * This is the central lockd service.
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?
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/sysctl.h>
19 #include <linux/moduleparam.h>
21 #include <linux/sched/signal.h>
22 #include <linux/errno.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>
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>
38 #include <net/addrconf.h>
40 #include <linux/lockd/lockd.h>
41 #include <linux/nfs.h>
46 #define NLMDBG_FACILITY NLMDBG_SVC
47 #define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
48 #define ALLOWED_SIGS (sigmask(SIGKILL))
50 static struct svc_program nlmsvc_program;
52 const struct nlmsvc_binding *nlmsvc_ops;
53 EXPORT_SYMBOL_GPL(nlmsvc_ops);
55 static DEFINE_MUTEX(nlmsvc_mutex);
56 static unsigned int nlmsvc_users;
57 static struct svc_serv *nlmsvc_serv;
58 unsigned long nlmsvc_timeout;
60 unsigned int lockd_net_id;
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
66 static unsigned long nlm_grace_period;
67 static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
68 static int nlm_udpport, nlm_tcpport;
70 /* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
71 static unsigned int nlm_max_connections = 1024;
74 * Constants needed for the sysctl interface.
76 static const unsigned long nlm_grace_period_min = 0;
77 static const unsigned long nlm_grace_period_max = 240;
78 static const unsigned long nlm_timeout_min = 3;
79 static const unsigned long nlm_timeout_max = 20;
80 static const int nlm_port_min = 0, nlm_port_max = 65535;
83 static struct ctl_table_header * nlm_sysctl_table;
86 static unsigned long get_lockd_grace_period(void)
88 /* Note: nlm_timeout should always be nonzero */
90 return roundup(nlm_grace_period, nlm_timeout) * HZ;
92 return nlm_timeout * 5 * HZ;
95 static void grace_ender(struct work_struct *grace)
97 struct delayed_work *dwork = to_delayed_work(grace);
98 struct lockd_net *ln = container_of(dwork, struct lockd_net,
101 locks_end_grace(&ln->lockd_manager);
104 static void set_grace_period(struct net *net)
106 unsigned long grace_period = get_lockd_grace_period();
107 struct lockd_net *ln = net_generic(net, lockd_net_id);
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);
114 static void restart_grace(void)
117 struct net *net = &init_net;
118 struct lockd_net *ln = net_generic(net, lockd_net_id);
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);
128 * This is the lockd kernel thread
134 struct svc_rqst *rqstp = vrqstp;
135 struct net *net = &init_net;
136 struct lockd_net *ln = net_generic(net, lockd_net_id);
138 /* try_to_freeze() is called from svc_recv() */
141 /* Allow SIGKILL to tell lockd to drop all of its locks */
142 allow_signal(SIGKILL);
144 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
147 * The main request loop. We don't terminate until the last
148 * NFS mount or NFS daemon has gone away.
150 while (!kthread_should_stop()) {
151 long timeout = MAX_SCHEDULE_TIMEOUT;
152 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
154 /* update sv_maxconn if it has changed */
155 rqstp->rq_server->sv_maxconn = nlm_max_connections;
158 flush_signals(current);
163 timeout = nlmsvc_retry_blocked();
166 * Find a socket with data available and call its
169 err = svc_recv(rqstp, timeout);
170 if (err == -EAGAIN || err == -EINTR)
172 dprintk("lockd: request from %s\n",
173 svc_print_addr(rqstp, buf, sizeof(buf)));
177 flush_signals(current);
179 nlmsvc_invalidate_all();
180 nlm_shutdown_hosts();
181 cancel_delayed_work_sync(&ln->grace_period_end);
182 locks_end_grace(&ln->lockd_manager);
184 dprintk("lockd_down: service stopped\n");
186 svc_exit_thread(rqstp);
188 module_put_and_kthread_exit(0);
191 static int create_lockd_listener(struct svc_serv *serv, const char *name,
192 struct net *net, const int family,
193 const unsigned short port,
194 const struct cred *cred)
196 struct svc_xprt *xprt;
198 xprt = svc_find_xprt(serv, name, net, family, 0);
200 return svc_create_xprt(serv, name, net, family, port,
201 SVC_SOCK_DEFAULTS, cred);
206 static int create_lockd_family(struct svc_serv *serv, struct net *net,
207 const int family, const struct cred *cred)
211 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport,
216 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport,
221 * Ensure there are active UDP and TCP listeners for lockd.
223 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
224 * local services (such as rpc.statd) still require UDP, and
225 * some NFS servers do not yet support NLM over TCP.
227 * Returns zero if all listeners are available; otherwise a
228 * negative errno value is returned.
230 static int make_socks(struct svc_serv *serv, struct net *net,
231 const struct cred *cred)
236 err = create_lockd_family(serv, net, PF_INET, cred);
240 err = create_lockd_family(serv, net, PF_INET6, cred);
241 if (err < 0 && err != -EAFNOSUPPORT)
250 "lockd_up: makesock failed, error=%d\n", err);
251 svc_shutdown_net(serv, net);
255 static int lockd_up_net(struct svc_serv *serv, struct net *net,
256 const struct cred *cred)
258 struct lockd_net *ln = net_generic(net, lockd_net_id);
261 if (ln->nlmsvc_users++)
264 error = svc_bind(serv, net);
268 error = make_socks(serv, net, cred);
271 set_grace_period(net);
272 dprintk("%s: per-net data created; net=%x\n", __func__, net->ns.inum);
280 static void lockd_down_net(struct svc_serv *serv, struct net *net)
282 struct lockd_net *ln = net_generic(net, lockd_net_id);
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_shutdown_net(serv, net);
290 dprintk("%s: per-net data destroyed; net=%x\n",
291 __func__, net->ns.inum);
294 pr_err("%s: no users! net=%x\n",
295 __func__, net->ns.inum);
300 static int lockd_inetaddr_event(struct notifier_block *this,
301 unsigned long event, void *ptr)
303 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
304 struct sockaddr_in sin;
306 if (event != NETDEV_DOWN)
310 dprintk("lockd_inetaddr_event: removed %pI4\n",
312 sin.sin_family = AF_INET;
313 sin.sin_addr.s_addr = ifa->ifa_local;
314 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin);
321 static struct notifier_block lockd_inetaddr_notifier = {
322 .notifier_call = lockd_inetaddr_event,
325 #if IS_ENABLED(CONFIG_IPV6)
326 static int lockd_inet6addr_event(struct notifier_block *this,
327 unsigned long event, void *ptr)
329 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
330 struct sockaddr_in6 sin6;
332 if (event != NETDEV_DOWN)
336 dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
337 sin6.sin6_family = AF_INET6;
338 sin6.sin6_addr = ifa->addr;
339 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
340 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
341 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin6);
348 static struct notifier_block lockd_inet6addr_notifier = {
349 .notifier_call = lockd_inet6addr_event,
353 static const struct svc_serv_ops lockd_sv_ops = {
354 .svo_shutdown = svc_rpcb_cleanup,
355 .svo_function = lockd,
356 .svo_enqueue_xprt = svc_xprt_do_enqueue,
357 .svo_module = THIS_MODULE,
360 static int lockd_get(void)
362 struct svc_serv *serv;
366 svc_get(nlmsvc_serv);
372 * Sanity check: if there's no pid,
373 * we should be the first user ...
377 "lockd_up: no pid, %d users??\n", nlmsvc_users);
380 nlm_timeout = LOCKD_DFLT_TIMEO;
381 nlmsvc_timeout = nlm_timeout * HZ;
383 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, &lockd_sv_ops);
385 printk(KERN_WARNING "lockd_up: create service failed\n");
389 serv->sv_maxconn = nlm_max_connections;
390 error = svc_set_num_threads(serv, NULL, 1);
391 /* The thread now holds the only reference */
397 register_inetaddr_notifier(&lockd_inetaddr_notifier);
398 #if IS_ENABLED(CONFIG_IPV6)
399 register_inet6addr_notifier(&lockd_inet6addr_notifier);
401 dprintk("lockd_up: service created\n");
406 static void lockd_put(void)
408 if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
413 unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
414 #if IS_ENABLED(CONFIG_IPV6)
415 unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
418 svc_set_num_threads(nlmsvc_serv, NULL, 0);
420 dprintk("lockd_down: service destroyed\n");
424 * Bring up the lockd process if it's not already up.
426 int lockd_up(struct net *net, const struct cred *cred)
430 mutex_lock(&nlmsvc_mutex);
436 error = lockd_up_net(nlmsvc_serv, net, cred);
443 mutex_unlock(&nlmsvc_mutex);
446 EXPORT_SYMBOL_GPL(lockd_up);
449 * Decrement the user count and bring down lockd if we're the last.
452 lockd_down(struct net *net)
454 mutex_lock(&nlmsvc_mutex);
455 lockd_down_net(nlmsvc_serv, net);
457 mutex_unlock(&nlmsvc_mutex);
459 EXPORT_SYMBOL_GPL(lockd_down);
464 * Sysctl parameters (same as module parameters, different interface).
467 static struct ctl_table nlm_sysctls[] = {
469 .procname = "nlm_grace_period",
470 .data = &nlm_grace_period,
471 .maxlen = sizeof(unsigned long),
473 .proc_handler = proc_doulongvec_minmax,
474 .extra1 = (unsigned long *) &nlm_grace_period_min,
475 .extra2 = (unsigned long *) &nlm_grace_period_max,
478 .procname = "nlm_timeout",
479 .data = &nlm_timeout,
480 .maxlen = sizeof(unsigned long),
482 .proc_handler = proc_doulongvec_minmax,
483 .extra1 = (unsigned long *) &nlm_timeout_min,
484 .extra2 = (unsigned long *) &nlm_timeout_max,
487 .procname = "nlm_udpport",
488 .data = &nlm_udpport,
489 .maxlen = sizeof(int),
491 .proc_handler = proc_dointvec_minmax,
492 .extra1 = (int *) &nlm_port_min,
493 .extra2 = (int *) &nlm_port_max,
496 .procname = "nlm_tcpport",
497 .data = &nlm_tcpport,
498 .maxlen = sizeof(int),
500 .proc_handler = proc_dointvec_minmax,
501 .extra1 = (int *) &nlm_port_min,
502 .extra2 = (int *) &nlm_port_max,
505 .procname = "nsm_use_hostnames",
506 .data = &nsm_use_hostnames,
507 .maxlen = sizeof(int),
509 .proc_handler = proc_dobool,
512 .procname = "nsm_local_state",
513 .data = &nsm_local_state,
514 .maxlen = sizeof(int),
516 .proc_handler = proc_dointvec,
521 static struct ctl_table nlm_sysctl_dir[] = {
525 .child = nlm_sysctls,
530 static struct ctl_table nlm_sysctl_root[] = {
534 .child = nlm_sysctl_dir,
539 #endif /* CONFIG_SYSCTL */
542 * Module (and sysfs) parameters.
545 #define param_set_min_max(name, type, which_strtol, min, max) \
546 static int param_set_##name(const char *val, const struct kernel_param *kp) \
549 __typeof__(type) num = which_strtol(val, &endp, 0); \
550 if (endp == val || *endp || num < (min) || num > (max)) \
552 *((type *) kp->arg) = num; \
556 static inline int is_callback(u32 proc)
558 return proc == NLMPROC_GRANTED
559 || proc == NLMPROC_GRANTED_MSG
560 || proc == NLMPROC_TEST_RES
561 || proc == NLMPROC_LOCK_RES
562 || proc == NLMPROC_CANCEL_RES
563 || proc == NLMPROC_UNLOCK_RES
564 || proc == NLMPROC_NSM_NOTIFY;
568 static int lockd_authenticate(struct svc_rqst *rqstp)
570 rqstp->rq_client = NULL;
571 switch (rqstp->rq_authop->flavour) {
574 rqstp->rq_auth_stat = rpc_auth_ok;
575 if (rqstp->rq_proc == 0)
577 if (is_callback(rqstp->rq_proc)) {
578 /* Leave it to individual procedures to
579 * call nlmsvc_lookup_host(rqstp)
583 return svc_set_client(rqstp);
585 rqstp->rq_auth_stat = rpc_autherr_badcred;
590 param_set_min_max(port, int, simple_strtol, 0, 65535)
591 param_set_min_max(grace_period, unsigned long, simple_strtoul,
592 nlm_grace_period_min, nlm_grace_period_max)
593 param_set_min_max(timeout, unsigned long, simple_strtoul,
594 nlm_timeout_min, nlm_timeout_max)
597 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
598 MODULE_LICENSE("GPL");
600 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
601 &nlm_grace_period, 0644);
602 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
604 module_param_call(nlm_udpport, param_set_port, param_get_int,
606 module_param_call(nlm_tcpport, param_set_port, param_get_int,
608 module_param(nsm_use_hostnames, bool, 0644);
609 module_param(nlm_max_connections, uint, 0644);
611 static int lockd_init_net(struct net *net)
613 struct lockd_net *ln = net_generic(net, lockd_net_id);
615 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
616 INIT_LIST_HEAD(&ln->lockd_manager.list);
617 ln->lockd_manager.block_opens = false;
618 INIT_LIST_HEAD(&ln->nsm_handles);
622 static void lockd_exit_net(struct net *net)
624 struct lockd_net *ln = net_generic(net, lockd_net_id);
626 WARN_ONCE(!list_empty(&ln->lockd_manager.list),
627 "net %x %s: lockd_manager.list is not empty\n",
628 net->ns.inum, __func__);
629 WARN_ONCE(!list_empty(&ln->nsm_handles),
630 "net %x %s: nsm_handles list is not empty\n",
631 net->ns.inum, __func__);
632 WARN_ONCE(delayed_work_pending(&ln->grace_period_end),
633 "net %x %s: grace_period_end was not cancelled\n",
634 net->ns.inum, __func__);
637 static struct pernet_operations lockd_net_ops = {
638 .init = lockd_init_net,
639 .exit = lockd_exit_net,
641 .size = sizeof(struct lockd_net),
646 * Initialising and terminating the module.
649 static int __init init_nlm(void)
655 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
656 if (nlm_sysctl_table == NULL)
659 err = register_pernet_subsys(&lockd_net_ops);
663 err = lockd_create_procfs();
670 unregister_pernet_subsys(&lockd_net_ops);
673 unregister_sysctl_table(nlm_sysctl_table);
679 static void __exit exit_nlm(void)
681 /* FIXME: delete all NLM clients */
682 nlm_shutdown_hosts();
683 lockd_remove_procfs();
684 unregister_pernet_subsys(&lockd_net_ops);
686 unregister_sysctl_table(nlm_sysctl_table);
690 module_init(init_nlm);
691 module_exit(exit_nlm);
694 * nlmsvc_dispatch - Process an NLM Request
695 * @rqstp: incoming request
696 * @statp: pointer to location of accept_stat field in RPC Reply buffer
699 * %0: Processing complete; do not send a Reply
700 * %1: Processing complete; send Reply in rqstp->rq_res
702 static int nlmsvc_dispatch(struct svc_rqst *rqstp, __be32 *statp)
704 const struct svc_procedure *procp = rqstp->rq_procinfo;
706 svcxdr_init_decode(rqstp);
707 if (!procp->pc_decode(rqstp, &rqstp->rq_arg_stream))
710 *statp = procp->pc_func(rqstp);
711 if (*statp == rpc_drop_reply)
713 if (*statp != rpc_success)
716 svcxdr_init_encode(rqstp);
717 if (!procp->pc_encode(rqstp, &rqstp->rq_res_stream))
723 *statp = rpc_garbage_args;
727 *statp = rpc_system_err;
732 * Define NLM program and procedures
734 static unsigned int nlmsvc_version1_count[17];
735 static const struct svc_version nlmsvc_version1 = {
738 .vs_proc = nlmsvc_procedures,
739 .vs_count = nlmsvc_version1_count,
740 .vs_dispatch = nlmsvc_dispatch,
741 .vs_xdrsize = NLMSVC_XDRSIZE,
743 static unsigned int nlmsvc_version3_count[24];
744 static const struct svc_version nlmsvc_version3 = {
747 .vs_proc = nlmsvc_procedures,
748 .vs_count = nlmsvc_version3_count,
749 .vs_dispatch = nlmsvc_dispatch,
750 .vs_xdrsize = NLMSVC_XDRSIZE,
752 #ifdef CONFIG_LOCKD_V4
753 static unsigned int nlmsvc_version4_count[24];
754 static const struct svc_version nlmsvc_version4 = {
757 .vs_proc = nlmsvc_procedures4,
758 .vs_count = nlmsvc_version4_count,
759 .vs_dispatch = nlmsvc_dispatch,
760 .vs_xdrsize = NLMSVC_XDRSIZE,
763 static const struct svc_version *nlmsvc_version[] = {
764 [1] = &nlmsvc_version1,
765 [3] = &nlmsvc_version3,
766 #ifdef CONFIG_LOCKD_V4
767 [4] = &nlmsvc_version4,
771 static struct svc_stat nlmsvc_stats;
773 #define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
774 static struct svc_program nlmsvc_program = {
775 .pg_prog = NLM_PROGRAM, /* program number */
776 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
777 .pg_vers = nlmsvc_version, /* version table */
778 .pg_name = "lockd", /* service name */
779 .pg_class = "nfsd", /* share authentication with nfsd */
780 .pg_stats = &nlmsvc_stats, /* stats table */
781 .pg_authenticate = &lockd_authenticate, /* export authentication */
782 .pg_init_request = svc_generic_init_request,
783 .pg_rpcbind_set = svc_generic_rpcbind_set,