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#include "netlink.h"
45
46#define NLMDBG_FACILITY NLMDBG_SVC
47#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
48
49static struct svc_program nlmsvc_program;
50
51const struct nlmsvc_binding *nlmsvc_ops;
52EXPORT_SYMBOL_GPL(nlmsvc_ops);
53
54static DEFINE_MUTEX(nlmsvc_mutex);
55static unsigned int nlmsvc_users;
56static struct svc_serv *nlmsvc_serv;
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;
71unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
72static int nlm_udpport, nlm_tcpport;
73
74/*
75 * Constants needed for the sysctl interface.
76 */
77static const unsigned long nlm_grace_period_min = 0;
78static const unsigned long nlm_grace_period_max = 240;
79static const unsigned long nlm_timeout_min = 3;
80static const unsigned long nlm_timeout_max = 20;
81
82#ifdef CONFIG_SYSCTL
83static const int nlm_port_min = 0, nlm_port_max = 65535;
84static struct ctl_table_header * nlm_sysctl_table;
85#endif
86
87static unsigned long get_lockd_grace_period(struct net *net)
88{
89 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
90
91 /* Return the net-ns specific grace period, if there is one */
92 if (ln->gracetime)
93 return ln->gracetime * HZ;
94
95 /* Note: nlm_timeout should always be nonzero */
96 if (nlm_grace_period)
97 return roundup(nlm_grace_period, nlm_timeout) * HZ;
98 else
99 return nlm_timeout * 5 * HZ;
100}
101
102static void grace_ender(struct work_struct *grace)
103{
104 struct delayed_work *dwork = to_delayed_work(work: grace);
105 struct lockd_net *ln = container_of(dwork, struct lockd_net,
106 grace_period_end);
107
108 locks_end_grace(&ln->lockd_manager);
109}
110
111static void set_grace_period(struct net *net)
112{
113 unsigned long grace_period = get_lockd_grace_period(net);
114 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
115
116 locks_start_grace(net, &ln->lockd_manager);
117 cancel_delayed_work_sync(dwork: &ln->grace_period_end);
118 schedule_delayed_work(dwork: &ln->grace_period_end, delay: grace_period);
119}
120
121/*
122 * This is the lockd kernel thread
123 */
124static int
125lockd(void *vrqstp)
126{
127 struct svc_rqst *rqstp = vrqstp;
128 struct net *net = &init_net;
129 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
130
131 svc_thread_init_status(rqstp, err: 0);
132
133 /* try_to_freeze() is called from svc_recv() */
134 set_freezable();
135
136 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
137
138 /*
139 * The main request loop. We don't terminate until the last
140 * NFS mount or NFS daemon has gone away.
141 */
142 while (!svc_thread_should_stop(rqstp)) {
143 nlmsvc_retry_blocked(rqstp);
144 svc_recv(rqstp);
145 }
146 if (nlmsvc_ops)
147 nlmsvc_invalidate_all();
148 nlm_shutdown_hosts();
149 cancel_delayed_work_sync(dwork: &ln->grace_period_end);
150 locks_end_grace(&ln->lockd_manager);
151
152 dprintk("lockd_down: service stopped\n");
153
154 svc_exit_thread(rqstp);
155 return 0;
156}
157
158static int create_lockd_listener(struct svc_serv *serv, const char *name,
159 struct net *net, const int family,
160 const unsigned short port,
161 const struct cred *cred)
162{
163 struct svc_xprt *xprt;
164
165 xprt = svc_find_xprt(serv, xcl_name: name, net, af: family, port: 0);
166 if (xprt == NULL)
167 return svc_xprt_create(serv, xprt_name: name, net, family, port,
168 SVC_SOCK_DEFAULTS, cred);
169 svc_xprt_put(xprt);
170 return 0;
171}
172
173static int create_lockd_family(struct svc_serv *serv, struct net *net,
174 const int family, const struct cred *cred)
175{
176 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
177 int err;
178
179 err = create_lockd_listener(serv, name: "udp", net, family,
180 port: ln->udp_port ? ln->udp_port : nlm_udpport, cred);
181 if (err < 0)
182 return err;
183
184 return create_lockd_listener(serv, name: "tcp", net, family,
185 port: ln->tcp_port ? ln->tcp_port : nlm_tcpport, cred);
186}
187
188/*
189 * Ensure there are active UDP and TCP listeners for lockd.
190 *
191 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
192 * local services (such as rpc.statd) still require UDP, and
193 * some NFS servers do not yet support NLM over TCP.
194 *
195 * Returns zero if all listeners are available; otherwise a
196 * negative errno value is returned.
197 */
198static int make_socks(struct svc_serv *serv, struct net *net,
199 const struct cred *cred)
200{
201 static int warned;
202 int err;
203
204 err = create_lockd_family(serv, net, PF_INET, cred);
205 if (err < 0)
206 goto out_err;
207
208 err = create_lockd_family(serv, net, PF_INET6, cred);
209 if (err < 0 && err != -EAFNOSUPPORT)
210 goto out_err;
211
212 warned = 0;
213 return 0;
214
215out_err:
216 if (warned++ == 0)
217 printk(KERN_WARNING
218 "lockd_up: makesock failed, error=%d\n", err);
219 svc_xprt_destroy_all(serv, net, unregister: true);
220 return err;
221}
222
223static int lockd_up_net(struct svc_serv *serv, struct net *net,
224 const struct cred *cred)
225{
226 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
227 int error;
228
229 if (ln->nlmsvc_users++)
230 return 0;
231
232 error = svc_bind(serv, net);
233 if (error)
234 goto err_bind;
235
236 error = make_socks(serv, net, cred);
237 if (error < 0)
238 goto err_bind;
239 set_grace_period(net);
240 dprintk("%s: per-net data created; net=%x\n", __func__, net->ns.inum);
241 return 0;
242
243err_bind:
244 ln->nlmsvc_users--;
245 return error;
246}
247
248static void lockd_down_net(struct svc_serv *serv, struct net *net)
249{
250 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
251
252 if (ln->nlmsvc_users) {
253 if (--ln->nlmsvc_users == 0) {
254 nlm_shutdown_hosts_net(net);
255 cancel_delayed_work_sync(dwork: &ln->grace_period_end);
256 locks_end_grace(&ln->lockd_manager);
257 svc_xprt_destroy_all(serv, net, unregister: true);
258 }
259 } else {
260 pr_err("%s: no users! net=%x\n",
261 __func__, net->ns.inum);
262 BUG();
263 }
264}
265
266static int lockd_inetaddr_event(struct notifier_block *this,
267 unsigned long event, void *ptr)
268{
269 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
270 struct sockaddr_in sin;
271
272 if (event != NETDEV_DOWN)
273 goto out;
274
275 if (nlmsvc_serv) {
276 dprintk("lockd_inetaddr_event: removed %pI4\n",
277 &ifa->ifa_local);
278 sin.sin_family = AF_INET;
279 sin.sin_addr.s_addr = ifa->ifa_local;
280 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin);
281 }
282
283out:
284 return NOTIFY_DONE;
285}
286
287static struct notifier_block lockd_inetaddr_notifier = {
288 .notifier_call = lockd_inetaddr_event,
289};
290
291#if IS_ENABLED(CONFIG_IPV6)
292static int lockd_inet6addr_event(struct notifier_block *this,
293 unsigned long event, void *ptr)
294{
295 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
296 struct sockaddr_in6 sin6;
297
298 if (event != NETDEV_DOWN)
299 goto out;
300
301 if (nlmsvc_serv) {
302 dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
303 sin6.sin6_family = AF_INET6;
304 sin6.sin6_addr = ifa->addr;
305 if (ipv6_addr_type(addr: &sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
306 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
307 svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin6);
308 }
309
310out:
311 return NOTIFY_DONE;
312}
313
314static struct notifier_block lockd_inet6addr_notifier = {
315 .notifier_call = lockd_inet6addr_event,
316};
317#endif
318
319static int lockd_get(void)
320{
321 struct svc_serv *serv;
322 int error;
323
324 if (nlmsvc_serv) {
325 nlmsvc_users++;
326 return 0;
327 }
328
329 /*
330 * Sanity check: if there's no pid,
331 * we should be the first user ...
332 */
333 if (nlmsvc_users)
334 printk(KERN_WARNING
335 "lockd_up: no pid, %d users??\n", nlmsvc_users);
336
337 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, threadfn: lockd);
338 if (!serv) {
339 printk(KERN_WARNING "lockd_up: create service failed\n");
340 return -ENOMEM;
341 }
342
343 error = svc_set_num_threads(serv, NULL, 1);
344 if (error < 0) {
345 svc_destroy(svcp: &serv);
346 return error;
347 }
348
349 nlmsvc_serv = serv;
350 register_inetaddr_notifier(nb: &lockd_inetaddr_notifier);
351#if IS_ENABLED(CONFIG_IPV6)
352 register_inet6addr_notifier(nb: &lockd_inet6addr_notifier);
353#endif
354 dprintk("lockd_up: service created\n");
355 nlmsvc_users++;
356 return 0;
357}
358
359static void lockd_put(void)
360{
361 if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
362 return;
363 if (--nlmsvc_users)
364 return;
365
366 unregister_inetaddr_notifier(nb: &lockd_inetaddr_notifier);
367#if IS_ENABLED(CONFIG_IPV6)
368 unregister_inet6addr_notifier(nb: &lockd_inet6addr_notifier);
369#endif
370
371 svc_set_num_threads(nlmsvc_serv, NULL, 0);
372 timer_delete_sync(timer: &nlmsvc_retry);
373 svc_destroy(svcp: &nlmsvc_serv);
374 dprintk("lockd_down: service destroyed\n");
375}
376
377/*
378 * Bring up the lockd process if it's not already up.
379 */
380int lockd_up(struct net *net, const struct cred *cred)
381{
382 int error;
383
384 mutex_lock(&nlmsvc_mutex);
385
386 error = lockd_get();
387 if (error)
388 goto err;
389
390 error = lockd_up_net(serv: nlmsvc_serv, net, cred);
391 if (error < 0) {
392 lockd_put();
393 goto err;
394 }
395
396err:
397 mutex_unlock(lock: &nlmsvc_mutex);
398 return error;
399}
400EXPORT_SYMBOL_GPL(lockd_up);
401
402/*
403 * Decrement the user count and bring down lockd if we're the last.
404 */
405void
406lockd_down(struct net *net)
407{
408 mutex_lock(&nlmsvc_mutex);
409 lockd_down_net(serv: nlmsvc_serv, net);
410 lockd_put();
411 mutex_unlock(lock: &nlmsvc_mutex);
412}
413EXPORT_SYMBOL_GPL(lockd_down);
414
415#ifdef CONFIG_SYSCTL
416
417/*
418 * Sysctl parameters (same as module parameters, different interface).
419 */
420
421static const struct ctl_table nlm_sysctls[] = {
422 {
423 .procname = "nlm_grace_period",
424 .data = &nlm_grace_period,
425 .maxlen = sizeof(unsigned long),
426 .mode = 0644,
427 .proc_handler = proc_doulongvec_minmax,
428 .extra1 = (unsigned long *) &nlm_grace_period_min,
429 .extra2 = (unsigned long *) &nlm_grace_period_max,
430 },
431 {
432 .procname = "nlm_timeout",
433 .data = &nlm_timeout,
434 .maxlen = sizeof(unsigned long),
435 .mode = 0644,
436 .proc_handler = proc_doulongvec_minmax,
437 .extra1 = (unsigned long *) &nlm_timeout_min,
438 .extra2 = (unsigned long *) &nlm_timeout_max,
439 },
440 {
441 .procname = "nlm_udpport",
442 .data = &nlm_udpport,
443 .maxlen = sizeof(int),
444 .mode = 0644,
445 .proc_handler = proc_dointvec_minmax,
446 .extra1 = (int *) &nlm_port_min,
447 .extra2 = (int *) &nlm_port_max,
448 },
449 {
450 .procname = "nlm_tcpport",
451 .data = &nlm_tcpport,
452 .maxlen = sizeof(int),
453 .mode = 0644,
454 .proc_handler = proc_dointvec_minmax,
455 .extra1 = (int *) &nlm_port_min,
456 .extra2 = (int *) &nlm_port_max,
457 },
458 {
459 .procname = "nsm_use_hostnames",
460 .data = &nsm_use_hostnames,
461 .maxlen = sizeof(bool),
462 .mode = 0644,
463 .proc_handler = proc_dobool,
464 },
465 {
466 .procname = "nsm_local_state",
467 .data = &nsm_local_state,
468 .maxlen = sizeof(nsm_local_state),
469 .mode = 0644,
470 .proc_handler = proc_douintvec,
471 .extra1 = SYSCTL_ZERO,
472 },
473};
474
475#endif /* CONFIG_SYSCTL */
476
477/*
478 * Module (and sysfs) parameters.
479 */
480
481#define param_set_min_max(name, type, which_strtol, min, max) \
482static int param_set_##name(const char *val, const struct kernel_param *kp) \
483{ \
484 char *endp; \
485 __typeof__(type) num = which_strtol(val, &endp, 0); \
486 if (endp == val || *endp || num < (min) || num > (max)) \
487 return -EINVAL; \
488 *((type *) kp->arg) = num; \
489 return 0; \
490}
491
492static inline int is_callback(u32 proc)
493{
494 return proc == NLMPROC_GRANTED
495 || proc == NLMPROC_GRANTED_MSG
496 || proc == NLMPROC_TEST_RES
497 || proc == NLMPROC_LOCK_RES
498 || proc == NLMPROC_CANCEL_RES
499 || proc == NLMPROC_UNLOCK_RES
500 || proc == NLMPROC_NSM_NOTIFY;
501}
502
503
504static enum svc_auth_status lockd_authenticate(struct svc_rqst *rqstp)
505{
506 rqstp->rq_client = NULL;
507 switch (rqstp->rq_authop->flavour) {
508 case RPC_AUTH_NULL:
509 case RPC_AUTH_UNIX:
510 rqstp->rq_auth_stat = rpc_auth_ok;
511 if (rqstp->rq_proc == 0)
512 return SVC_OK;
513 if (is_callback(proc: rqstp->rq_proc)) {
514 /* Leave it to individual procedures to
515 * call nlmsvc_lookup_host(rqstp)
516 */
517 return SVC_OK;
518 }
519 return svc_set_client(rqstp);
520 }
521 rqstp->rq_auth_stat = rpc_autherr_badcred;
522 return SVC_DENIED;
523}
524
525
526param_set_min_max(port, int, simple_strtol, 0, 65535)
527param_set_min_max(grace_period, unsigned long, simple_strtoul,
528 nlm_grace_period_min, nlm_grace_period_max)
529param_set_min_max(timeout, unsigned long, simple_strtoul,
530 nlm_timeout_min, nlm_timeout_max)
531
532MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
533MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
534MODULE_LICENSE("GPL");
535
536module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
537 &nlm_grace_period, 0644);
538module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
539 &nlm_timeout, 0644);
540module_param_call(nlm_udpport, param_set_port, param_get_int,
541 &nlm_udpport, 0644);
542module_param_call(nlm_tcpport, param_set_port, param_get_int,
543 &nlm_tcpport, 0644);
544module_param(nsm_use_hostnames, bool, 0644);
545
546static int lockd_init_net(struct net *net)
547{
548 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
549
550 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
551 INIT_LIST_HEAD(list: &ln->lockd_manager.list);
552 ln->lockd_manager.block_opens = false;
553 INIT_LIST_HEAD(list: &ln->nsm_handles);
554 return 0;
555}
556
557static void lockd_exit_net(struct net *net)
558{
559 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
560
561 WARN_ONCE(!list_empty(&ln->lockd_manager.list),
562 "net %x %s: lockd_manager.list is not empty\n",
563 net->ns.inum, __func__);
564 WARN_ONCE(!list_empty(&ln->nsm_handles),
565 "net %x %s: nsm_handles list is not empty\n",
566 net->ns.inum, __func__);
567 WARN_ONCE(delayed_work_pending(&ln->grace_period_end),
568 "net %x %s: grace_period_end was not cancelled\n",
569 net->ns.inum, __func__);
570}
571
572static struct pernet_operations lockd_net_ops = {
573 .init = lockd_init_net,
574 .exit = lockd_exit_net,
575 .id = &lockd_net_id,
576 .size = sizeof(struct lockd_net),
577};
578
579
580/*
581 * Initialising and terminating the module.
582 */
583
584static int __init init_nlm(void)
585{
586 int err;
587
588#ifdef CONFIG_SYSCTL
589 err = -ENOMEM;
590 nlm_sysctl_table = register_sysctl("fs/nfs", nlm_sysctls);
591 if (nlm_sysctl_table == NULL)
592 goto err_sysctl;
593#endif
594 err = register_pernet_subsys(&lockd_net_ops);
595 if (err)
596 goto err_pernet;
597
598 err = genl_register_family(family: &lockd_nl_family);
599 if (err)
600 goto err_netlink;
601
602 err = lockd_create_procfs();
603 if (err)
604 goto err_procfs;
605
606 return 0;
607
608err_procfs:
609 genl_unregister_family(family: &lockd_nl_family);
610err_netlink:
611 unregister_pernet_subsys(&lockd_net_ops);
612err_pernet:
613#ifdef CONFIG_SYSCTL
614 unregister_sysctl_table(table: nlm_sysctl_table);
615err_sysctl:
616#endif
617 return err;
618}
619
620static void __exit exit_nlm(void)
621{
622 /* FIXME: delete all NLM clients */
623 nlm_shutdown_hosts();
624 genl_unregister_family(family: &lockd_nl_family);
625 lockd_remove_procfs();
626 unregister_pernet_subsys(&lockd_net_ops);
627#ifdef CONFIG_SYSCTL
628 unregister_sysctl_table(table: nlm_sysctl_table);
629#endif
630}
631
632module_init(init_nlm);
633module_exit(exit_nlm);
634
635/**
636 * nlmsvc_dispatch - Process an NLM Request
637 * @rqstp: incoming request
638 *
639 * Return values:
640 * %0: Processing complete; do not send a Reply
641 * %1: Processing complete; send Reply in rqstp->rq_res
642 */
643static int nlmsvc_dispatch(struct svc_rqst *rqstp)
644{
645 const struct svc_procedure *procp = rqstp->rq_procinfo;
646 __be32 *statp = rqstp->rq_accept_statp;
647
648 if (!procp->pc_decode(rqstp, &rqstp->rq_arg_stream))
649 goto out_decode_err;
650
651 *statp = procp->pc_func(rqstp);
652 if (*statp == rpc_drop_reply)
653 return 0;
654 if (*statp != rpc_success)
655 return 1;
656
657 if (!procp->pc_encode(rqstp, &rqstp->rq_res_stream))
658 goto out_encode_err;
659
660 return 1;
661
662out_decode_err:
663 *statp = rpc_garbage_args;
664 return 1;
665
666out_encode_err:
667 *statp = rpc_system_err;
668 return 1;
669}
670
671/*
672 * Define NLM program and procedures
673 */
674static DEFINE_PER_CPU_ALIGNED(unsigned long, nlmsvc_version1_count[17]);
675static const struct svc_version nlmsvc_version1 = {
676 .vs_vers = 1,
677 .vs_nproc = 17,
678 .vs_proc = nlmsvc_procedures,
679 .vs_count = nlmsvc_version1_count,
680 .vs_dispatch = nlmsvc_dispatch,
681 .vs_xdrsize = NLMSVC_XDRSIZE,
682};
683
684static DEFINE_PER_CPU_ALIGNED(unsigned long,
685 nlmsvc_version3_count[ARRAY_SIZE(nlmsvc_procedures)]);
686static const struct svc_version nlmsvc_version3 = {
687 .vs_vers = 3,
688 .vs_nproc = ARRAY_SIZE(nlmsvc_procedures),
689 .vs_proc = nlmsvc_procedures,
690 .vs_count = nlmsvc_version3_count,
691 .vs_dispatch = nlmsvc_dispatch,
692 .vs_xdrsize = NLMSVC_XDRSIZE,
693};
694
695#ifdef CONFIG_LOCKD_V4
696static DEFINE_PER_CPU_ALIGNED(unsigned long,
697 nlmsvc_version4_count[ARRAY_SIZE(nlmsvc_procedures4)]);
698static const struct svc_version nlmsvc_version4 = {
699 .vs_vers = 4,
700 .vs_nproc = ARRAY_SIZE(nlmsvc_procedures4),
701 .vs_proc = nlmsvc_procedures4,
702 .vs_count = nlmsvc_version4_count,
703 .vs_dispatch = nlmsvc_dispatch,
704 .vs_xdrsize = NLMSVC_XDRSIZE,
705};
706#endif
707
708static const struct svc_version *nlmsvc_version[] = {
709 [1] = &nlmsvc_version1,
710 [3] = &nlmsvc_version3,
711#ifdef CONFIG_LOCKD_V4
712 [4] = &nlmsvc_version4,
713#endif
714};
715
716#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
717static struct svc_program nlmsvc_program = {
718 .pg_prog = NLM_PROGRAM, /* program number */
719 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
720 .pg_vers = nlmsvc_version, /* version table */
721 .pg_name = "lockd", /* service name */
722 .pg_class = "nfsd", /* share authentication with nfsd */
723 .pg_authenticate = &lockd_authenticate, /* export authentication */
724 .pg_init_request = svc_generic_init_request,
725 .pg_rpcbind_set = svc_generic_rpcbind_set,
726};
727
728/**
729 * lockd_nl_server_set_doit - set the lockd server parameters via netlink
730 * @skb: reply buffer
731 * @info: netlink metadata and command arguments
732 *
733 * This updates the per-net values. When updating the values in the init_net
734 * namespace, also update the "legacy" global values.
735 *
736 * Return 0 on success or a negative errno.
737 */
738int lockd_nl_server_set_doit(struct sk_buff *skb, struct genl_info *info)
739{
740 struct net *net = genl_info_net(info);
741 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
742 const struct nlattr *attr;
743
744 if (GENL_REQ_ATTR_CHECK(info, LOCKD_A_SERVER_GRACETIME))
745 return -EINVAL;
746
747 if (info->attrs[LOCKD_A_SERVER_GRACETIME] ||
748 info->attrs[LOCKD_A_SERVER_TCP_PORT] ||
749 info->attrs[LOCKD_A_SERVER_UDP_PORT]) {
750 attr = info->attrs[LOCKD_A_SERVER_GRACETIME];
751 if (attr) {
752 u32 gracetime = nla_get_u32(nla: attr);
753
754 if (gracetime > nlm_grace_period_max)
755 return -EINVAL;
756
757 ln->gracetime = gracetime;
758
759 if (net == &init_net)
760 nlm_grace_period = gracetime;
761 }
762
763 attr = info->attrs[LOCKD_A_SERVER_TCP_PORT];
764 if (attr) {
765 ln->tcp_port = nla_get_u16(nla: attr);
766 if (net == &init_net)
767 nlm_tcpport = ln->tcp_port;
768 }
769
770 attr = info->attrs[LOCKD_A_SERVER_UDP_PORT];
771 if (attr) {
772 ln->udp_port = nla_get_u16(nla: attr);
773 if (net == &init_net)
774 nlm_udpport = ln->udp_port;
775 }
776 }
777 return 0;
778}
779
780/**
781 * lockd_nl_server_get_doit - get lockd server parameters via netlink
782 * @skb: reply buffer
783 * @info: netlink metadata and command arguments
784 *
785 * Return 0 on success or a negative errno.
786 */
787int lockd_nl_server_get_doit(struct sk_buff *skb, struct genl_info *info)
788{
789 struct net *net = genl_info_net(info);
790 struct lockd_net *ln = net_generic(net, id: lockd_net_id);
791 void *hdr;
792 int err;
793
794 skb = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
795 if (!skb)
796 return -ENOMEM;
797
798 hdr = genlmsg_iput(skb, info);
799 if (!hdr) {
800 err = -EMSGSIZE;
801 goto err_free_msg;
802 }
803
804 err = nla_put_u32(skb, attrtype: LOCKD_A_SERVER_GRACETIME, value: ln->gracetime) ||
805 nla_put_u16(skb, attrtype: LOCKD_A_SERVER_TCP_PORT, value: ln->tcp_port) ||
806 nla_put_u16(skb, attrtype: LOCKD_A_SERVER_UDP_PORT, value: ln->udp_port);
807 if (err)
808 goto err_free_msg;
809
810 genlmsg_end(skb, hdr);
811
812 return genlmsg_reply(skb, info);
813err_free_msg:
814 nlmsg_free(skb);
815
816 return err;
817}
818

source code of linux/fs/lockd/svc.c