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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/auth.c
4 *
5 * Generic RPC client authentication API.
6 *
7 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
8 */
9
10#include <linux/types.h>
11#include <linux/sched.h>
12#include <linux/cred.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15#include <linux/errno.h>
16#include <linux/hash.h>
17#include <linux/sunrpc/clnt.h>
18#include <linux/sunrpc/gss_api.h>
19#include <linux/spinlock.h>
20
21#include <trace/events/sunrpc.h>
22
23#define RPC_CREDCACHE_DEFAULT_HASHBITS (4)
24struct rpc_cred_cache {
25 struct hlist_head *hashtable;
26 unsigned int hashbits;
27 spinlock_t lock;
28};
29
30static unsigned int auth_hashbits = RPC_CREDCACHE_DEFAULT_HASHBITS;
31
32static const struct rpc_authops __rcu *auth_flavors[RPC_AUTH_MAXFLAVOR] = {
33 [RPC_AUTH_NULL] = (const struct rpc_authops __force __rcu *)&authnull_ops,
34 [RPC_AUTH_UNIX] = (const struct rpc_authops __force __rcu *)&authunix_ops,
35 NULL, /* others can be loadable modules */
36};
37
38static LIST_HEAD(cred_unused);
39static unsigned long number_cred_unused;
40
41static struct cred machine_cred = {
42 .usage = ATOMIC_INIT(1),
43#ifdef CONFIG_DEBUG_CREDENTIALS
44 .magic = CRED_MAGIC,
45#endif
46};
47
48/*
49 * Return the machine_cred pointer to be used whenever
50 * the a generic machine credential is needed.
51 */
52const struct cred *rpc_machine_cred(void)
53{
54 return &machine_cred;
55}
56EXPORT_SYMBOL_GPL(rpc_machine_cred);
57
58#define MAX_HASHTABLE_BITS (14)
59static int param_set_hashtbl_sz(const char *val, const struct kernel_param *kp)
60{
61 unsigned long num;
62 unsigned int nbits;
63 int ret;
64
65 if (!val)
66 goto out_inval;
67 ret = kstrtoul(val, 0, &num);
68 if (ret)
69 goto out_inval;
70 nbits = fls(num - 1);
71 if (nbits > MAX_HASHTABLE_BITS || nbits < 2)
72 goto out_inval;
73 *(unsigned int *)kp->arg = nbits;
74 return 0;
75out_inval:
76 return -EINVAL;
77}
78
79static int param_get_hashtbl_sz(char *buffer, const struct kernel_param *kp)
80{
81 unsigned int nbits;
82
83 nbits = *(unsigned int *)kp->arg;
84 return sprintf(buffer, "%u", 1U << nbits);
85}
86
87#define param_check_hashtbl_sz(name, p) __param_check(name, p, unsigned int);
88
89static const struct kernel_param_ops param_ops_hashtbl_sz = {
90 .set = param_set_hashtbl_sz,
91 .get = param_get_hashtbl_sz,
92};
93
94module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644);
95MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size");
96
97static unsigned long auth_max_cred_cachesize = ULONG_MAX;
98module_param(auth_max_cred_cachesize, ulong, 0644);
99MODULE_PARM_DESC(auth_max_cred_cachesize, "RPC credential maximum total cache size");
100
101static u32
102pseudoflavor_to_flavor(u32 flavor) {
103 if (flavor > RPC_AUTH_MAXFLAVOR)
104 return RPC_AUTH_GSS;
105 return flavor;
106}
107
108int
109rpcauth_register(const struct rpc_authops *ops)
110{
111 const struct rpc_authops *old;
112 rpc_authflavor_t flavor;
113
114 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
115 return -EINVAL;
116 old = cmpxchg((const struct rpc_authops ** __force)&auth_flavors[flavor], NULL, ops);
117 if (old == NULL || old == ops)
118 return 0;
119 return -EPERM;
120}
121EXPORT_SYMBOL_GPL(rpcauth_register);
122
123int
124rpcauth_unregister(const struct rpc_authops *ops)
125{
126 const struct rpc_authops *old;
127 rpc_authflavor_t flavor;
128
129 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
130 return -EINVAL;
131
132 old = cmpxchg((const struct rpc_authops ** __force)&auth_flavors[flavor], ops, NULL);
133 if (old == ops || old == NULL)
134 return 0;
135 return -EPERM;
136}
137EXPORT_SYMBOL_GPL(rpcauth_unregister);
138
139static const struct rpc_authops *
140rpcauth_get_authops(rpc_authflavor_t flavor)
141{
142 const struct rpc_authops *ops;
143
144 if (flavor >= RPC_AUTH_MAXFLAVOR)
145 return NULL;
146
147 rcu_read_lock();
148 ops = rcu_dereference(auth_flavors[flavor]);
149 if (ops == NULL) {
150 rcu_read_unlock();
151 request_module("rpc-auth-%u", flavor);
152 rcu_read_lock();
153 ops = rcu_dereference(auth_flavors[flavor]);
154 if (ops == NULL)
155 goto out;
156 }
157 if (!try_module_get(ops->owner))
158 ops = NULL;
159out:
160 rcu_read_unlock();
161 return ops;
162}
163
164static void
165rpcauth_put_authops(const struct rpc_authops *ops)
166{
167 module_put(ops->owner);
168}
169
170/**
171 * rpcauth_get_pseudoflavor - check if security flavor is supported
172 * @flavor: a security flavor
173 * @info: a GSS mech OID, quality of protection, and service value
174 *
175 * Verifies that an appropriate kernel module is available or already loaded.
176 * Returns an equivalent pseudoflavor, or RPC_AUTH_MAXFLAVOR if "flavor" is
177 * not supported locally.
178 */
179rpc_authflavor_t
180rpcauth_get_pseudoflavor(rpc_authflavor_t flavor, struct rpcsec_gss_info *info)
181{
182 const struct rpc_authops *ops = rpcauth_get_authops(flavor);
183 rpc_authflavor_t pseudoflavor;
184
185 if (!ops)
186 return RPC_AUTH_MAXFLAVOR;
187 pseudoflavor = flavor;
188 if (ops->info2flavor != NULL)
189 pseudoflavor = ops->info2flavor(info);
190
191 rpcauth_put_authops(ops);
192 return pseudoflavor;
193}
194EXPORT_SYMBOL_GPL(rpcauth_get_pseudoflavor);
195
196/**
197 * rpcauth_get_gssinfo - find GSS tuple matching a GSS pseudoflavor
198 * @pseudoflavor: GSS pseudoflavor to match
199 * @info: rpcsec_gss_info structure to fill in
200 *
201 * Returns zero and fills in "info" if pseudoflavor matches a
202 * supported mechanism.
203 */
204int
205rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info)
206{
207 rpc_authflavor_t flavor = pseudoflavor_to_flavor(pseudoflavor);
208 const struct rpc_authops *ops;
209 int result;
210
211 ops = rpcauth_get_authops(flavor);
212 if (ops == NULL)
213 return -ENOENT;
214
215 result = -ENOENT;
216 if (ops->flavor2info != NULL)
217 result = ops->flavor2info(pseudoflavor, info);
218
219 rpcauth_put_authops(ops);
220 return result;
221}
222EXPORT_SYMBOL_GPL(rpcauth_get_gssinfo);
223
224/**
225 * rpcauth_list_flavors - discover registered flavors and pseudoflavors
226 * @array: array to fill in
227 * @size: size of "array"
228 *
229 * Returns the number of array items filled in, or a negative errno.
230 *
231 * The returned array is not sorted by any policy. Callers should not
232 * rely on the order of the items in the returned array.
233 */
234int
235rpcauth_list_flavors(rpc_authflavor_t *array, int size)
236{
237 const struct rpc_authops *ops;
238 rpc_authflavor_t flavor, pseudos[4];
239 int i, len, result = 0;
240
241 rcu_read_lock();
242 for (flavor = 0; flavor < RPC_AUTH_MAXFLAVOR; flavor++) {
243 ops = rcu_dereference(auth_flavors[flavor]);
244 if (result >= size) {
245 result = -ENOMEM;
246 break;
247 }
248
249 if (ops == NULL)
250 continue;
251 if (ops->list_pseudoflavors == NULL) {
252 array[result++] = ops->au_flavor;
253 continue;
254 }
255 len = ops->list_pseudoflavors(pseudos, ARRAY_SIZE(pseudos));
256 if (len < 0) {
257 result = len;
258 break;
259 }
260 for (i = 0; i < len; i++) {
261 if (result >= size) {
262 result = -ENOMEM;
263 break;
264 }
265 array[result++] = pseudos[i];
266 }
267 }
268 rcu_read_unlock();
269 return result;
270}
271EXPORT_SYMBOL_GPL(rpcauth_list_flavors);
272
273struct rpc_auth *
274rpcauth_create(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
275{
276 struct rpc_auth *auth = ERR_PTR(-EINVAL);
277 const struct rpc_authops *ops;
278 u32 flavor = pseudoflavor_to_flavor(args->pseudoflavor);
279
280 ops = rpcauth_get_authops(flavor);
281 if (ops == NULL)
282 goto out;
283
284 auth = ops->create(args, clnt);
285
286 rpcauth_put_authops(ops);
287 if (IS_ERR(auth))
288 return auth;
289 if (clnt->cl_auth)
290 rpcauth_release(clnt->cl_auth);
291 clnt->cl_auth = auth;
292
293out:
294 return auth;
295}
296EXPORT_SYMBOL_GPL(rpcauth_create);
297
298void
299rpcauth_release(struct rpc_auth *auth)
300{
301 if (!refcount_dec_and_test(&auth->au_count))
302 return;
303 auth->au_ops->destroy(auth);
304}
305
306static DEFINE_SPINLOCK(rpc_credcache_lock);
307
308/*
309 * On success, the caller is responsible for freeing the reference
310 * held by the hashtable
311 */
312static bool
313rpcauth_unhash_cred_locked(struct rpc_cred *cred)
314{
315 if (!test_and_clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags))
316 return false;
317 hlist_del_rcu(&cred->cr_hash);
318 return true;
319}
320
321static bool
322rpcauth_unhash_cred(struct rpc_cred *cred)
323{
324 spinlock_t *cache_lock;
325 bool ret;
326
327 if (!test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags))
328 return false;
329 cache_lock = &cred->cr_auth->au_credcache->lock;
330 spin_lock(cache_lock);
331 ret = rpcauth_unhash_cred_locked(cred);
332 spin_unlock(cache_lock);
333 return ret;
334}
335
336/*
337 * Initialize RPC credential cache
338 */
339int
340rpcauth_init_credcache(struct rpc_auth *auth)
341{
342 struct rpc_cred_cache *new;
343 unsigned int hashsize;
344
345 new = kmalloc(sizeof(*new), GFP_KERNEL);
346 if (!new)
347 goto out_nocache;
348 new->hashbits = auth_hashbits;
349 hashsize = 1U << new->hashbits;
350 new->hashtable = kcalloc(hashsize, sizeof(new->hashtable[0]), GFP_KERNEL);
351 if (!new->hashtable)
352 goto out_nohashtbl;
353 spin_lock_init(&new->lock);
354 auth->au_credcache = new;
355 return 0;
356out_nohashtbl:
357 kfree(new);
358out_nocache:
359 return -ENOMEM;
360}
361EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
362
363char *
364rpcauth_stringify_acceptor(struct rpc_cred *cred)
365{
366 if (!cred->cr_ops->crstringify_acceptor)
367 return NULL;
368 return cred->cr_ops->crstringify_acceptor(cred);
369}
370EXPORT_SYMBOL_GPL(rpcauth_stringify_acceptor);
371
372/*
373 * Destroy a list of credentials
374 */
375static inline
376void rpcauth_destroy_credlist(struct list_head *head)
377{
378 struct rpc_cred *cred;
379
380 while (!list_empty(head)) {
381 cred = list_entry(head->next, struct rpc_cred, cr_lru);
382 list_del_init(&cred->cr_lru);
383 put_rpccred(cred);
384 }
385}
386
387static void
388rpcauth_lru_add_locked(struct rpc_cred *cred)
389{
390 if (!list_empty(&cred->cr_lru))
391 return;
392 number_cred_unused++;
393 list_add_tail(&cred->cr_lru, &cred_unused);
394}
395
396static void
397rpcauth_lru_add(struct rpc_cred *cred)
398{
399 if (!list_empty(&cred->cr_lru))
400 return;
401 spin_lock(&rpc_credcache_lock);
402 rpcauth_lru_add_locked(cred);
403 spin_unlock(&rpc_credcache_lock);
404}
405
406static void
407rpcauth_lru_remove_locked(struct rpc_cred *cred)
408{
409 if (list_empty(&cred->cr_lru))
410 return;
411 number_cred_unused--;
412 list_del_init(&cred->cr_lru);
413}
414
415static void
416rpcauth_lru_remove(struct rpc_cred *cred)
417{
418 if (list_empty(&cred->cr_lru))
419 return;
420 spin_lock(&rpc_credcache_lock);
421 rpcauth_lru_remove_locked(cred);
422 spin_unlock(&rpc_credcache_lock);
423}
424
425/*
426 * Clear the RPC credential cache, and delete those credentials
427 * that are not referenced.
428 */
429void
430rpcauth_clear_credcache(struct rpc_cred_cache *cache)
431{
432 LIST_HEAD(free);
433 struct hlist_head *head;
434 struct rpc_cred *cred;
435 unsigned int hashsize = 1U << cache->hashbits;
436 int i;
437
438 spin_lock(&rpc_credcache_lock);
439 spin_lock(&cache->lock);
440 for (i = 0; i < hashsize; i++) {
441 head = &cache->hashtable[i];
442 while (!hlist_empty(head)) {
443 cred = hlist_entry(head->first, struct rpc_cred, cr_hash);
444 rpcauth_unhash_cred_locked(cred);
445 /* Note: We now hold a reference to cred */
446 rpcauth_lru_remove_locked(cred);
447 list_add_tail(&cred->cr_lru, &free);
448 }
449 }
450 spin_unlock(&cache->lock);
451 spin_unlock(&rpc_credcache_lock);
452 rpcauth_destroy_credlist(&free);
453}
454
455/*
456 * Destroy the RPC credential cache
457 */
458void
459rpcauth_destroy_credcache(struct rpc_auth *auth)
460{
461 struct rpc_cred_cache *cache = auth->au_credcache;
462
463 if (cache) {
464 auth->au_credcache = NULL;
465 rpcauth_clear_credcache(cache);
466 kfree(cache->hashtable);
467 kfree(cache);
468 }
469}
470EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
471
472
473#define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ)
474
475/*
476 * Remove stale credentials. Avoid sleeping inside the loop.
477 */
478static long
479rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
480{
481 struct rpc_cred *cred, *next;
482 unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
483 long freed = 0;
484
485 list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) {
486
487 if (nr_to_scan-- == 0)
488 break;
489 if (refcount_read(&cred->cr_count) > 1) {
490 rpcauth_lru_remove_locked(cred);
491 continue;
492 }
493 /*
494 * Enforce a 60 second garbage collection moratorium
495 * Note that the cred_unused list must be time-ordered.
496 */
497 if (!time_in_range(cred->cr_expire, expired, jiffies))
498 continue;
499 if (!rpcauth_unhash_cred(cred))
500 continue;
501
502 rpcauth_lru_remove_locked(cred);
503 freed++;
504 list_add_tail(&cred->cr_lru, free);
505 }
506 return freed ? freed : SHRINK_STOP;
507}
508
509static unsigned long
510rpcauth_cache_do_shrink(int nr_to_scan)
511{
512 LIST_HEAD(free);
513 unsigned long freed;
514
515 spin_lock(&rpc_credcache_lock);
516 freed = rpcauth_prune_expired(&free, nr_to_scan);
517 spin_unlock(&rpc_credcache_lock);
518 rpcauth_destroy_credlist(&free);
519
520 return freed;
521}
522
523/*
524 * Run memory cache shrinker.
525 */
526static unsigned long
527rpcauth_cache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
528
529{
530 if ((sc->gfp_mask & GFP_KERNEL) != GFP_KERNEL)
531 return SHRINK_STOP;
532
533 /* nothing left, don't come back */
534 if (list_empty(&cred_unused))
535 return SHRINK_STOP;
536
537 return rpcauth_cache_do_shrink(sc->nr_to_scan);
538}
539
540static unsigned long
541rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
542
543{
544 return number_cred_unused * sysctl_vfs_cache_pressure / 100;
545}
546
547static void
548rpcauth_cache_enforce_limit(void)
549{
550 unsigned long diff;
551 unsigned int nr_to_scan;
552
553 if (number_cred_unused <= auth_max_cred_cachesize)
554 return;
555 diff = number_cred_unused - auth_max_cred_cachesize;
556 nr_to_scan = 100;
557 if (diff < nr_to_scan)
558 nr_to_scan = diff;
559 rpcauth_cache_do_shrink(nr_to_scan);
560}
561
562/*
563 * Look up a process' credentials in the authentication cache
564 */
565struct rpc_cred *
566rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
567 int flags, gfp_t gfp)
568{
569 LIST_HEAD(free);
570 struct rpc_cred_cache *cache = auth->au_credcache;
571 struct rpc_cred *cred = NULL,
572 *entry, *new;
573 unsigned int nr;
574
575 nr = auth->au_ops->hash_cred(acred, cache->hashbits);
576
577 rcu_read_lock();
578 hlist_for_each_entry_rcu(entry, &cache->hashtable[nr], cr_hash) {
579 if (!entry->cr_ops->crmatch(acred, entry, flags))
580 continue;
581 cred = get_rpccred(entry);
582 if (cred)
583 break;
584 }
585 rcu_read_unlock();
586
587 if (cred != NULL)
588 goto found;
589
590 new = auth->au_ops->crcreate(auth, acred, flags, gfp);
591 if (IS_ERR(new)) {
592 cred = new;
593 goto out;
594 }
595
596 spin_lock(&cache->lock);
597 hlist_for_each_entry(entry, &cache->hashtable[nr], cr_hash) {
598 if (!entry->cr_ops->crmatch(acred, entry, flags))
599 continue;
600 cred = get_rpccred(entry);
601 if (cred)
602 break;
603 }
604 if (cred == NULL) {
605 cred = new;
606 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
607 refcount_inc(&cred->cr_count);
608 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
609 } else
610 list_add_tail(&new->cr_lru, &free);
611 spin_unlock(&cache->lock);
612 rpcauth_cache_enforce_limit();
613found:
614 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
615 cred->cr_ops->cr_init != NULL &&
616 !(flags & RPCAUTH_LOOKUP_NEW)) {
617 int res = cred->cr_ops->cr_init(auth, cred);
618 if (res < 0) {
619 put_rpccred(cred);
620 cred = ERR_PTR(res);
621 }
622 }
623 rpcauth_destroy_credlist(&free);
624out:
625 return cred;
626}
627EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
628
629struct rpc_cred *
630rpcauth_lookupcred(struct rpc_auth *auth, int flags)
631{
632 struct auth_cred acred;
633 struct rpc_cred *ret;
634 const struct cred *cred = current_cred();
635
636 memset(&acred, 0, sizeof(acred));
637 acred.cred = cred;
638 ret = auth->au_ops->lookup_cred(auth, &acred, flags);
639 return ret;
640}
641EXPORT_SYMBOL_GPL(rpcauth_lookupcred);
642
643void
644rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
645 struct rpc_auth *auth, const struct rpc_credops *ops)
646{
647 INIT_HLIST_NODE(&cred->cr_hash);
648 INIT_LIST_HEAD(&cred->cr_lru);
649 refcount_set(&cred->cr_count, 1);
650 cred->cr_auth = auth;
651 cred->cr_flags = 0;
652 cred->cr_ops = ops;
653 cred->cr_expire = jiffies;
654 cred->cr_cred = get_cred(acred->cred);
655}
656EXPORT_SYMBOL_GPL(rpcauth_init_cred);
657
658static struct rpc_cred *
659rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags)
660{
661 struct rpc_auth *auth = task->tk_client->cl_auth;
662 struct auth_cred acred = {
663 .cred = get_task_cred(&init_task),
664 };
665 struct rpc_cred *ret;
666
667 ret = auth->au_ops->lookup_cred(auth, &acred, lookupflags);
668 put_cred(acred.cred);
669 return ret;
670}
671
672static struct rpc_cred *
673rpcauth_bind_machine_cred(struct rpc_task *task, int lookupflags)
674{
675 struct rpc_auth *auth = task->tk_client->cl_auth;
676 struct auth_cred acred = {
677 .principal = task->tk_client->cl_principal,
678 .cred = init_task.cred,
679 };
680
681 if (!acred.principal)
682 return NULL;
683 return auth->au_ops->lookup_cred(auth, &acred, lookupflags);
684}
685
686static struct rpc_cred *
687rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags)
688{
689 struct rpc_auth *auth = task->tk_client->cl_auth;
690
691 return rpcauth_lookupcred(auth, lookupflags);
692}
693
694static int
695rpcauth_bindcred(struct rpc_task *task, const struct cred *cred, int flags)
696{
697 struct rpc_rqst *req = task->tk_rqstp;
698 struct rpc_cred *new = NULL;
699 int lookupflags = 0;
700 struct rpc_auth *auth = task->tk_client->cl_auth;
701 struct auth_cred acred = {
702 .cred = cred,
703 };
704
705 if (flags & RPC_TASK_ASYNC)
706 lookupflags |= RPCAUTH_LOOKUP_NEW;
707 if (task->tk_op_cred)
708 /* Task must use exactly this rpc_cred */
709 new = get_rpccred(task->tk_op_cred);
710 else if (cred != NULL && cred != &machine_cred)
711 new = auth->au_ops->lookup_cred(auth, &acred, lookupflags);
712 else if (cred == &machine_cred)
713 new = rpcauth_bind_machine_cred(task, lookupflags);
714
715 /* If machine cred couldn't be bound, try a root cred */
716 if (new)
717 ;
718 else if (cred == &machine_cred || (flags & RPC_TASK_ROOTCREDS))
719 new = rpcauth_bind_root_cred(task, lookupflags);
720 else if (flags & RPC_TASK_NULLCREDS)
721 new = authnull_ops.lookup_cred(NULL, NULL, 0);
722 else
723 new = rpcauth_bind_new_cred(task, lookupflags);
724 if (IS_ERR(new))
725 return PTR_ERR(new);
726 put_rpccred(req->rq_cred);
727 req->rq_cred = new;
728 return 0;
729}
730
731void
732put_rpccred(struct rpc_cred *cred)
733{
734 if (cred == NULL)
735 return;
736 rcu_read_lock();
737 if (refcount_dec_and_test(&cred->cr_count))
738 goto destroy;
739 if (refcount_read(&cred->cr_count) != 1 ||
740 !test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags))
741 goto out;
742 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) {
743 cred->cr_expire = jiffies;
744 rpcauth_lru_add(cred);
745 /* Race breaker */
746 if (unlikely(!test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags)))
747 rpcauth_lru_remove(cred);
748 } else if (rpcauth_unhash_cred(cred)) {
749 rpcauth_lru_remove(cred);
750 if (refcount_dec_and_test(&cred->cr_count))
751 goto destroy;
752 }
753out:
754 rcu_read_unlock();
755 return;
756destroy:
757 rcu_read_unlock();
758 cred->cr_ops->crdestroy(cred);
759}
760EXPORT_SYMBOL_GPL(put_rpccred);
761
762/**
763 * rpcauth_marshcred - Append RPC credential to end of @xdr
764 * @task: controlling RPC task
765 * @xdr: xdr_stream containing initial portion of RPC Call header
766 *
767 * On success, an appropriate verifier is added to @xdr, @xdr is
768 * updated to point past the verifier, and zero is returned.
769 * Otherwise, @xdr is in an undefined state and a negative errno
770 * is returned.
771 */
772int rpcauth_marshcred(struct rpc_task *task, struct xdr_stream *xdr)
773{
774 const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops;
775
776 return ops->crmarshal(task, xdr);
777}
778
779/**
780 * rpcauth_wrap_req_encode - XDR encode the RPC procedure
781 * @task: controlling RPC task
782 * @xdr: stream where on-the-wire bytes are to be marshalled
783 *
784 * On success, @xdr contains the encoded and wrapped message.
785 * Otherwise, @xdr is in an undefined state.
786 */
787int rpcauth_wrap_req_encode(struct rpc_task *task, struct xdr_stream *xdr)
788{
789 kxdreproc_t encode = task->tk_msg.rpc_proc->p_encode;
790
791 encode(task->tk_rqstp, xdr, task->tk_msg.rpc_argp);
792 return 0;
793}
794EXPORT_SYMBOL_GPL(rpcauth_wrap_req_encode);
795
796/**
797 * rpcauth_wrap_req - XDR encode and wrap the RPC procedure
798 * @task: controlling RPC task
799 * @xdr: stream where on-the-wire bytes are to be marshalled
800 *
801 * On success, @xdr contains the encoded and wrapped message,
802 * and zero is returned. Otherwise, @xdr is in an undefined
803 * state and a negative errno is returned.
804 */
805int rpcauth_wrap_req(struct rpc_task *task, struct xdr_stream *xdr)
806{
807 const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops;
808
809 return ops->crwrap_req(task, xdr);
810}
811
812/**
813 * rpcauth_checkverf - Validate verifier in RPC Reply header
814 * @task: controlling RPC task
815 * @xdr: xdr_stream containing RPC Reply header
816 *
817 * On success, @xdr is updated to point past the verifier and
818 * zero is returned. Otherwise, @xdr is in an undefined state
819 * and a negative errno is returned.
820 */
821int
822rpcauth_checkverf(struct rpc_task *task, struct xdr_stream *xdr)
823{
824 const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops;
825
826 return ops->crvalidate(task, xdr);
827}
828
829/**
830 * rpcauth_unwrap_resp_decode - Invoke XDR decode function
831 * @task: controlling RPC task
832 * @xdr: stream where the Reply message resides
833 *
834 * Returns zero on success; otherwise a negative errno is returned.
835 */
836int
837rpcauth_unwrap_resp_decode(struct rpc_task *task, struct xdr_stream *xdr)
838{
839 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
840
841 return decode(task->tk_rqstp, xdr, task->tk_msg.rpc_resp);
842}
843EXPORT_SYMBOL_GPL(rpcauth_unwrap_resp_decode);
844
845/**
846 * rpcauth_unwrap_resp - Invoke unwrap and decode function for the cred
847 * @task: controlling RPC task
848 * @xdr: stream where the Reply message resides
849 *
850 * Returns zero on success; otherwise a negative errno is returned.
851 */
852int
853rpcauth_unwrap_resp(struct rpc_task *task, struct xdr_stream *xdr)
854{
855 const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops;
856
857 return ops->crunwrap_resp(task, xdr);
858}
859
860bool
861rpcauth_xmit_need_reencode(struct rpc_task *task)
862{
863 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
864
865 if (!cred || !cred->cr_ops->crneed_reencode)
866 return false;
867 return cred->cr_ops->crneed_reencode(task);
868}
869
870int
871rpcauth_refreshcred(struct rpc_task *task)
872{
873 struct rpc_cred *cred;
874 int err;
875
876 cred = task->tk_rqstp->rq_cred;
877 if (cred == NULL) {
878 err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags);
879 if (err < 0)
880 goto out;
881 cred = task->tk_rqstp->rq_cred;
882 }
883
884 err = cred->cr_ops->crrefresh(task);
885out:
886 if (err < 0)
887 task->tk_status = err;
888 return err;
889}
890
891void
892rpcauth_invalcred(struct rpc_task *task)
893{
894 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
895
896 if (cred)
897 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
898}
899
900int
901rpcauth_uptodatecred(struct rpc_task *task)
902{
903 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
904
905 return cred == NULL ||
906 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
907}
908
909static struct shrinker rpc_cred_shrinker = {
910 .count_objects = rpcauth_cache_shrink_count,
911 .scan_objects = rpcauth_cache_shrink_scan,
912 .seeks = DEFAULT_SEEKS,
913};
914
915int __init rpcauth_init_module(void)
916{
917 int err;
918
919 err = rpc_init_authunix();
920 if (err < 0)
921 goto out1;
922 err = register_shrinker(&rpc_cred_shrinker);
923 if (err < 0)
924 goto out2;
925 return 0;
926out2:
927 rpc_destroy_authunix();
928out1:
929 return err;
930}
931
932void rpcauth_remove_module(void)
933{
934 rpc_destroy_authunix();
935 unregister_shrinker(&rpc_cred_shrinker);
936}
1/*
2 * linux/net/sunrpc/auth.c
3 *
4 * Generic RPC client authentication API.
5 *
6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
7 */
8
9#include <linux/types.h>
10#include <linux/sched.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/errno.h>
14#include <linux/hash.h>
15#include <linux/sunrpc/clnt.h>
16#include <linux/spinlock.h>
17
18#ifdef RPC_DEBUG
19# define RPCDBG_FACILITY RPCDBG_AUTH
20#endif
21
22#define RPC_CREDCACHE_DEFAULT_HASHBITS (4)
23struct rpc_cred_cache {
24 struct hlist_head *hashtable;
25 unsigned int hashbits;
26 spinlock_t lock;
27};
28
29static unsigned int auth_hashbits = RPC_CREDCACHE_DEFAULT_HASHBITS;
30
31static DEFINE_SPINLOCK(rpc_authflavor_lock);
32static const struct rpc_authops *auth_flavors[RPC_AUTH_MAXFLAVOR] = {
33 &authnull_ops, /* AUTH_NULL */
34 &authunix_ops, /* AUTH_UNIX */
35 NULL, /* others can be loadable modules */
36};
37
38static LIST_HEAD(cred_unused);
39static unsigned long number_cred_unused;
40
41#define MAX_HASHTABLE_BITS (14)
42static int param_set_hashtbl_sz(const char *val, const struct kernel_param *kp)
43{
44 unsigned long num;
45 unsigned int nbits;
46 int ret;
47
48 if (!val)
49 goto out_inval;
50 ret = strict_strtoul(val, 0, &num);
51 if (ret == -EINVAL)
52 goto out_inval;
53 nbits = fls(num);
54 if (num > (1U << nbits))
55 nbits++;
56 if (nbits > MAX_HASHTABLE_BITS || nbits < 2)
57 goto out_inval;
58 *(unsigned int *)kp->arg = nbits;
59 return 0;
60out_inval:
61 return -EINVAL;
62}
63
64static int param_get_hashtbl_sz(char *buffer, const struct kernel_param *kp)
65{
66 unsigned int nbits;
67
68 nbits = *(unsigned int *)kp->arg;
69 return sprintf(buffer, "%u", 1U << nbits);
70}
71
72#define param_check_hashtbl_sz(name, p) __param_check(name, p, unsigned int);
73
74static struct kernel_param_ops param_ops_hashtbl_sz = {
75 .set = param_set_hashtbl_sz,
76 .get = param_get_hashtbl_sz,
77};
78
79module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644);
80MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size");
81
82static u32
83pseudoflavor_to_flavor(u32 flavor) {
84 if (flavor >= RPC_AUTH_MAXFLAVOR)
85 return RPC_AUTH_GSS;
86 return flavor;
87}
88
89int
90rpcauth_register(const struct rpc_authops *ops)
91{
92 rpc_authflavor_t flavor;
93 int ret = -EPERM;
94
95 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
96 return -EINVAL;
97 spin_lock(&rpc_authflavor_lock);
98 if (auth_flavors[flavor] == NULL) {
99 auth_flavors[flavor] = ops;
100 ret = 0;
101 }
102 spin_unlock(&rpc_authflavor_lock);
103 return ret;
104}
105EXPORT_SYMBOL_GPL(rpcauth_register);
106
107int
108rpcauth_unregister(const struct rpc_authops *ops)
109{
110 rpc_authflavor_t flavor;
111 int ret = -EPERM;
112
113 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
114 return -EINVAL;
115 spin_lock(&rpc_authflavor_lock);
116 if (auth_flavors[flavor] == ops) {
117 auth_flavors[flavor] = NULL;
118 ret = 0;
119 }
120 spin_unlock(&rpc_authflavor_lock);
121 return ret;
122}
123EXPORT_SYMBOL_GPL(rpcauth_unregister);
124
125struct rpc_auth *
126rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
127{
128 struct rpc_auth *auth;
129 const struct rpc_authops *ops;
130 u32 flavor = pseudoflavor_to_flavor(pseudoflavor);
131
132 auth = ERR_PTR(-EINVAL);
133 if (flavor >= RPC_AUTH_MAXFLAVOR)
134 goto out;
135
136 if ((ops = auth_flavors[flavor]) == NULL)
137 request_module("rpc-auth-%u", flavor);
138 spin_lock(&rpc_authflavor_lock);
139 ops = auth_flavors[flavor];
140 if (ops == NULL || !try_module_get(ops->owner)) {
141 spin_unlock(&rpc_authflavor_lock);
142 goto out;
143 }
144 spin_unlock(&rpc_authflavor_lock);
145 auth = ops->create(clnt, pseudoflavor);
146 module_put(ops->owner);
147 if (IS_ERR(auth))
148 return auth;
149 if (clnt->cl_auth)
150 rpcauth_release(clnt->cl_auth);
151 clnt->cl_auth = auth;
152
153out:
154 return auth;
155}
156EXPORT_SYMBOL_GPL(rpcauth_create);
157
158void
159rpcauth_release(struct rpc_auth *auth)
160{
161 if (!atomic_dec_and_test(&auth->au_count))
162 return;
163 auth->au_ops->destroy(auth);
164}
165
166static DEFINE_SPINLOCK(rpc_credcache_lock);
167
168static void
169rpcauth_unhash_cred_locked(struct rpc_cred *cred)
170{
171 hlist_del_rcu(&cred->cr_hash);
172 smp_mb__before_clear_bit();
173 clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
174}
175
176static int
177rpcauth_unhash_cred(struct rpc_cred *cred)
178{
179 spinlock_t *cache_lock;
180 int ret;
181
182 cache_lock = &cred->cr_auth->au_credcache->lock;
183 spin_lock(cache_lock);
184 ret = atomic_read(&cred->cr_count) == 0;
185 if (ret)
186 rpcauth_unhash_cred_locked(cred);
187 spin_unlock(cache_lock);
188 return ret;
189}
190
191/*
192 * Initialize RPC credential cache
193 */
194int
195rpcauth_init_credcache(struct rpc_auth *auth)
196{
197 struct rpc_cred_cache *new;
198 unsigned int hashsize;
199
200 new = kmalloc(sizeof(*new), GFP_KERNEL);
201 if (!new)
202 goto out_nocache;
203 new->hashbits = auth_hashbits;
204 hashsize = 1U << new->hashbits;
205 new->hashtable = kcalloc(hashsize, sizeof(new->hashtable[0]), GFP_KERNEL);
206 if (!new->hashtable)
207 goto out_nohashtbl;
208 spin_lock_init(&new->lock);
209 auth->au_credcache = new;
210 return 0;
211out_nohashtbl:
212 kfree(new);
213out_nocache:
214 return -ENOMEM;
215}
216EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
217
218/*
219 * Destroy a list of credentials
220 */
221static inline
222void rpcauth_destroy_credlist(struct list_head *head)
223{
224 struct rpc_cred *cred;
225
226 while (!list_empty(head)) {
227 cred = list_entry(head->next, struct rpc_cred, cr_lru);
228 list_del_init(&cred->cr_lru);
229 put_rpccred(cred);
230 }
231}
232
233/*
234 * Clear the RPC credential cache, and delete those credentials
235 * that are not referenced.
236 */
237void
238rpcauth_clear_credcache(struct rpc_cred_cache *cache)
239{
240 LIST_HEAD(free);
241 struct hlist_head *head;
242 struct rpc_cred *cred;
243 unsigned int hashsize = 1U << cache->hashbits;
244 int i;
245
246 spin_lock(&rpc_credcache_lock);
247 spin_lock(&cache->lock);
248 for (i = 0; i < hashsize; i++) {
249 head = &cache->hashtable[i];
250 while (!hlist_empty(head)) {
251 cred = hlist_entry(head->first, struct rpc_cred, cr_hash);
252 get_rpccred(cred);
253 if (!list_empty(&cred->cr_lru)) {
254 list_del(&cred->cr_lru);
255 number_cred_unused--;
256 }
257 list_add_tail(&cred->cr_lru, &free);
258 rpcauth_unhash_cred_locked(cred);
259 }
260 }
261 spin_unlock(&cache->lock);
262 spin_unlock(&rpc_credcache_lock);
263 rpcauth_destroy_credlist(&free);
264}
265
266/*
267 * Destroy the RPC credential cache
268 */
269void
270rpcauth_destroy_credcache(struct rpc_auth *auth)
271{
272 struct rpc_cred_cache *cache = auth->au_credcache;
273
274 if (cache) {
275 auth->au_credcache = NULL;
276 rpcauth_clear_credcache(cache);
277 kfree(cache->hashtable);
278 kfree(cache);
279 }
280}
281EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
282
283
284#define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ)
285
286/*
287 * Remove stale credentials. Avoid sleeping inside the loop.
288 */
289static int
290rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
291{
292 spinlock_t *cache_lock;
293 struct rpc_cred *cred, *next;
294 unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
295
296 list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) {
297
298 if (nr_to_scan-- == 0)
299 break;
300 /*
301 * Enforce a 60 second garbage collection moratorium
302 * Note that the cred_unused list must be time-ordered.
303 */
304 if (time_in_range(cred->cr_expire, expired, jiffies) &&
305 test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0)
306 return 0;
307
308 list_del_init(&cred->cr_lru);
309 number_cred_unused--;
310 if (atomic_read(&cred->cr_count) != 0)
311 continue;
312
313 cache_lock = &cred->cr_auth->au_credcache->lock;
314 spin_lock(cache_lock);
315 if (atomic_read(&cred->cr_count) == 0) {
316 get_rpccred(cred);
317 list_add_tail(&cred->cr_lru, free);
318 rpcauth_unhash_cred_locked(cred);
319 }
320 spin_unlock(cache_lock);
321 }
322 return (number_cred_unused / 100) * sysctl_vfs_cache_pressure;
323}
324
325/*
326 * Run memory cache shrinker.
327 */
328static int
329rpcauth_cache_shrinker(struct shrinker *shrink, struct shrink_control *sc)
330{
331 LIST_HEAD(free);
332 int res;
333 int nr_to_scan = sc->nr_to_scan;
334 gfp_t gfp_mask = sc->gfp_mask;
335
336 if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
337 return (nr_to_scan == 0) ? 0 : -1;
338 if (list_empty(&cred_unused))
339 return 0;
340 spin_lock(&rpc_credcache_lock);
341 res = rpcauth_prune_expired(&free, nr_to_scan);
342 spin_unlock(&rpc_credcache_lock);
343 rpcauth_destroy_credlist(&free);
344 return res;
345}
346
347/*
348 * Look up a process' credentials in the authentication cache
349 */
350struct rpc_cred *
351rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
352 int flags)
353{
354 LIST_HEAD(free);
355 struct rpc_cred_cache *cache = auth->au_credcache;
356 struct hlist_node *pos;
357 struct rpc_cred *cred = NULL,
358 *entry, *new;
359 unsigned int nr;
360
361 nr = hash_long(acred->uid, cache->hashbits);
362
363 rcu_read_lock();
364 hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) {
365 if (!entry->cr_ops->crmatch(acred, entry, flags))
366 continue;
367 spin_lock(&cache->lock);
368 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
369 spin_unlock(&cache->lock);
370 continue;
371 }
372 cred = get_rpccred(entry);
373 spin_unlock(&cache->lock);
374 break;
375 }
376 rcu_read_unlock();
377
378 if (cred != NULL)
379 goto found;
380
381 new = auth->au_ops->crcreate(auth, acred, flags);
382 if (IS_ERR(new)) {
383 cred = new;
384 goto out;
385 }
386
387 spin_lock(&cache->lock);
388 hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) {
389 if (!entry->cr_ops->crmatch(acred, entry, flags))
390 continue;
391 cred = get_rpccred(entry);
392 break;
393 }
394 if (cred == NULL) {
395 cred = new;
396 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
397 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
398 } else
399 list_add_tail(&new->cr_lru, &free);
400 spin_unlock(&cache->lock);
401found:
402 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
403 cred->cr_ops->cr_init != NULL &&
404 !(flags & RPCAUTH_LOOKUP_NEW)) {
405 int res = cred->cr_ops->cr_init(auth, cred);
406 if (res < 0) {
407 put_rpccred(cred);
408 cred = ERR_PTR(res);
409 }
410 }
411 rpcauth_destroy_credlist(&free);
412out:
413 return cred;
414}
415EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
416
417struct rpc_cred *
418rpcauth_lookupcred(struct rpc_auth *auth, int flags)
419{
420 struct auth_cred acred;
421 struct rpc_cred *ret;
422 const struct cred *cred = current_cred();
423
424 dprintk("RPC: looking up %s cred\n",
425 auth->au_ops->au_name);
426
427 memset(&acred, 0, sizeof(acred));
428 acred.uid = cred->fsuid;
429 acred.gid = cred->fsgid;
430 acred.group_info = get_group_info(((struct cred *)cred)->group_info);
431
432 ret = auth->au_ops->lookup_cred(auth, &acred, flags);
433 put_group_info(acred.group_info);
434 return ret;
435}
436
437void
438rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
439 struct rpc_auth *auth, const struct rpc_credops *ops)
440{
441 INIT_HLIST_NODE(&cred->cr_hash);
442 INIT_LIST_HEAD(&cred->cr_lru);
443 atomic_set(&cred->cr_count, 1);
444 cred->cr_auth = auth;
445 cred->cr_ops = ops;
446 cred->cr_expire = jiffies;
447#ifdef RPC_DEBUG
448 cred->cr_magic = RPCAUTH_CRED_MAGIC;
449#endif
450 cred->cr_uid = acred->uid;
451}
452EXPORT_SYMBOL_GPL(rpcauth_init_cred);
453
454struct rpc_cred *
455rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags)
456{
457 dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid,
458 cred->cr_auth->au_ops->au_name, cred);
459 return get_rpccred(cred);
460}
461EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred);
462
463static struct rpc_cred *
464rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags)
465{
466 struct rpc_auth *auth = task->tk_client->cl_auth;
467 struct auth_cred acred = {
468 .uid = 0,
469 .gid = 0,
470 };
471
472 dprintk("RPC: %5u looking up %s cred\n",
473 task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
474 return auth->au_ops->lookup_cred(auth, &acred, lookupflags);
475}
476
477static struct rpc_cred *
478rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags)
479{
480 struct rpc_auth *auth = task->tk_client->cl_auth;
481
482 dprintk("RPC: %5u looking up %s cred\n",
483 task->tk_pid, auth->au_ops->au_name);
484 return rpcauth_lookupcred(auth, lookupflags);
485}
486
487static int
488rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags)
489{
490 struct rpc_rqst *req = task->tk_rqstp;
491 struct rpc_cred *new;
492 int lookupflags = 0;
493
494 if (flags & RPC_TASK_ASYNC)
495 lookupflags |= RPCAUTH_LOOKUP_NEW;
496 if (cred != NULL)
497 new = cred->cr_ops->crbind(task, cred, lookupflags);
498 else if (flags & RPC_TASK_ROOTCREDS)
499 new = rpcauth_bind_root_cred(task, lookupflags);
500 else
501 new = rpcauth_bind_new_cred(task, lookupflags);
502 if (IS_ERR(new))
503 return PTR_ERR(new);
504 if (req->rq_cred != NULL)
505 put_rpccred(req->rq_cred);
506 req->rq_cred = new;
507 return 0;
508}
509
510void
511put_rpccred(struct rpc_cred *cred)
512{
513 /* Fast path for unhashed credentials */
514 if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) {
515 if (atomic_dec_and_test(&cred->cr_count))
516 cred->cr_ops->crdestroy(cred);
517 return;
518 }
519
520 if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
521 return;
522 if (!list_empty(&cred->cr_lru)) {
523 number_cred_unused--;
524 list_del_init(&cred->cr_lru);
525 }
526 if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
527 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) {
528 cred->cr_expire = jiffies;
529 list_add_tail(&cred->cr_lru, &cred_unused);
530 number_cred_unused++;
531 goto out_nodestroy;
532 }
533 if (!rpcauth_unhash_cred(cred)) {
534 /* We were hashed and someone looked us up... */
535 goto out_nodestroy;
536 }
537 }
538 spin_unlock(&rpc_credcache_lock);
539 cred->cr_ops->crdestroy(cred);
540 return;
541out_nodestroy:
542 spin_unlock(&rpc_credcache_lock);
543}
544EXPORT_SYMBOL_GPL(put_rpccred);
545
546__be32 *
547rpcauth_marshcred(struct rpc_task *task, __be32 *p)
548{
549 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
550
551 dprintk("RPC: %5u marshaling %s cred %p\n",
552 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
553
554 return cred->cr_ops->crmarshal(task, p);
555}
556
557__be32 *
558rpcauth_checkverf(struct rpc_task *task, __be32 *p)
559{
560 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
561
562 dprintk("RPC: %5u validating %s cred %p\n",
563 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
564
565 return cred->cr_ops->crvalidate(task, p);
566}
567
568static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
569 __be32 *data, void *obj)
570{
571 struct xdr_stream xdr;
572
573 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data);
574 encode(rqstp, &xdr, obj);
575}
576
577int
578rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp,
579 __be32 *data, void *obj)
580{
581 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
582
583 dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
584 task->tk_pid, cred->cr_ops->cr_name, cred);
585 if (cred->cr_ops->crwrap_req)
586 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
587 /* By default, we encode the arguments normally. */
588 rpcauth_wrap_req_encode(encode, rqstp, data, obj);
589 return 0;
590}
591
592static int
593rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
594 __be32 *data, void *obj)
595{
596 struct xdr_stream xdr;
597
598 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data);
599 return decode(rqstp, &xdr, obj);
600}
601
602int
603rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp,
604 __be32 *data, void *obj)
605{
606 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
607
608 dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
609 task->tk_pid, cred->cr_ops->cr_name, cred);
610 if (cred->cr_ops->crunwrap_resp)
611 return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
612 data, obj);
613 /* By default, we decode the arguments normally. */
614 return rpcauth_unwrap_req_decode(decode, rqstp, data, obj);
615}
616
617int
618rpcauth_refreshcred(struct rpc_task *task)
619{
620 struct rpc_cred *cred;
621 int err;
622
623 cred = task->tk_rqstp->rq_cred;
624 if (cred == NULL) {
625 err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags);
626 if (err < 0)
627 goto out;
628 cred = task->tk_rqstp->rq_cred;
629 }
630 dprintk("RPC: %5u refreshing %s cred %p\n",
631 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
632
633 err = cred->cr_ops->crrefresh(task);
634out:
635 if (err < 0)
636 task->tk_status = err;
637 return err;
638}
639
640void
641rpcauth_invalcred(struct rpc_task *task)
642{
643 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
644
645 dprintk("RPC: %5u invalidating %s cred %p\n",
646 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
647 if (cred)
648 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
649}
650
651int
652rpcauth_uptodatecred(struct rpc_task *task)
653{
654 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
655
656 return cred == NULL ||
657 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
658}
659
660static struct shrinker rpc_cred_shrinker = {
661 .shrink = rpcauth_cache_shrinker,
662 .seeks = DEFAULT_SEEKS,
663};
664
665int __init rpcauth_init_module(void)
666{
667 int err;
668
669 err = rpc_init_authunix();
670 if (err < 0)
671 goto out1;
672 err = rpc_init_generic_auth();
673 if (err < 0)
674 goto out2;
675 register_shrinker(&rpc_cred_shrinker);
676 return 0;
677out2:
678 rpc_destroy_authunix();
679out1:
680 return err;
681}
682
683void rpcauth_remove_module(void)
684{
685 rpc_destroy_authunix();
686 rpc_destroy_generic_auth();
687 unregister_shrinker(&rpc_cred_shrinker);
688}