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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/sunrpc/gss_api.h>
17 #include <linux/spinlock.h>
18
19 #ifdef RPC_DEBUG
20 # define RPCDBG_FACILITY        RPCDBG_AUTH
21 #endif
22
23 #define RPC_CREDCACHE_DEFAULT_HASHBITS  (4)
24 struct rpc_cred_cache {
25         struct hlist_head       *hashtable;
26         unsigned int            hashbits;
27         spinlock_t              lock;
28 };
29
30 static unsigned int auth_hashbits = RPC_CREDCACHE_DEFAULT_HASHBITS;
31
32 static DEFINE_SPINLOCK(rpc_authflavor_lock);
33 static const struct rpc_authops *auth_flavors[RPC_AUTH_MAXFLAVOR] = {
34         &authnull_ops,          /* AUTH_NULL */
35         &authunix_ops,          /* AUTH_UNIX */
36         NULL,                   /* others can be loadable modules */
37 };
38
39 static LIST_HEAD(cred_unused);
40 static unsigned long number_cred_unused;
41
42 #define MAX_HASHTABLE_BITS (14)
43 static int param_set_hashtbl_sz(const char *val, const struct kernel_param *kp)
44 {
45         unsigned long num;
46         unsigned int nbits;
47         int ret;
48
49         if (!val)
50                 goto out_inval;
51         ret = strict_strtoul(val, 0, &num);
52         if (ret == -EINVAL)
53                 goto out_inval;
54         nbits = fls(num);
55         if (num > (1U << nbits))
56                 nbits++;
57         if (nbits > MAX_HASHTABLE_BITS || nbits < 2)
58                 goto out_inval;
59         *(unsigned int *)kp->arg = nbits;
60         return 0;
61 out_inval:
62         return -EINVAL;
63 }
64
65 static int param_get_hashtbl_sz(char *buffer, const struct kernel_param *kp)
66 {
67         unsigned int nbits;
68
69         nbits = *(unsigned int *)kp->arg;
70         return sprintf(buffer, "%u", 1U << nbits);
71 }
72
73 #define param_check_hashtbl_sz(name, p) __param_check(name, p, unsigned int);
74
75 static struct kernel_param_ops param_ops_hashtbl_sz = {
76         .set = param_set_hashtbl_sz,
77         .get = param_get_hashtbl_sz,
78 };
79
80 module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644);
81 MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size");
82
83 static u32
84 pseudoflavor_to_flavor(u32 flavor) {
85         if (flavor >= RPC_AUTH_MAXFLAVOR)
86                 return RPC_AUTH_GSS;
87         return flavor;
88 }
89
90 int
91 rpcauth_register(const struct rpc_authops *ops)
92 {
93         rpc_authflavor_t flavor;
94         int ret = -EPERM;
95
96         if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
97                 return -EINVAL;
98         spin_lock(&rpc_authflavor_lock);
99         if (auth_flavors[flavor] == NULL) {
100                 auth_flavors[flavor] = ops;
101                 ret = 0;
102         }
103         spin_unlock(&rpc_authflavor_lock);
104         return ret;
105 }
106 EXPORT_SYMBOL_GPL(rpcauth_register);
107
108 int
109 rpcauth_unregister(const struct rpc_authops *ops)
110 {
111         rpc_authflavor_t flavor;
112         int ret = -EPERM;
113
114         if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
115                 return -EINVAL;
116         spin_lock(&rpc_authflavor_lock);
117         if (auth_flavors[flavor] == ops) {
118                 auth_flavors[flavor] = NULL;
119                 ret = 0;
120         }
121         spin_unlock(&rpc_authflavor_lock);
122         return ret;
123 }
124 EXPORT_SYMBOL_GPL(rpcauth_unregister);
125
126 /**
127  * rpcauth_list_flavors - discover registered flavors and pseudoflavors
128  * @array: array to fill in
129  * @size: size of "array"
130  *
131  * Returns the number of array items filled in, or a negative errno.
132  *
133  * The returned array is not sorted by any policy.  Callers should not
134  * rely on the order of the items in the returned array.
135  */
136 int
137 rpcauth_list_flavors(rpc_authflavor_t *array, int size)
138 {
139         rpc_authflavor_t flavor;
140         int result = 0;
141
142         spin_lock(&rpc_authflavor_lock);
143         for (flavor = 0; flavor < RPC_AUTH_MAXFLAVOR; flavor++) {
144                 const struct rpc_authops *ops = auth_flavors[flavor];
145                 rpc_authflavor_t pseudos[4];
146                 int i, len;
147
148                 if (result >= size) {
149                         result = -ENOMEM;
150                         break;
151                 }
152
153                 if (ops == NULL)
154                         continue;
155                 if (ops->list_pseudoflavors == NULL) {
156                         array[result++] = ops->au_flavor;
157                         continue;
158                 }
159                 len = ops->list_pseudoflavors(pseudos, ARRAY_SIZE(pseudos));
160                 if (len < 0) {
161                         result = len;
162                         break;
163                 }
164                 for (i = 0; i < len; i++) {
165                         if (result >= size) {
166                                 result = -ENOMEM;
167                                 break;
168                         }
169                         array[result++] = pseudos[i];
170                 }
171         }
172         spin_unlock(&rpc_authflavor_lock);
173
174         dprintk("RPC:       %s returns %d\n", __func__, result);
175         return result;
176 }
177 EXPORT_SYMBOL_GPL(rpcauth_list_flavors);
178
179 struct rpc_auth *
180 rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
181 {
182         struct rpc_auth         *auth;
183         const struct rpc_authops *ops;
184         u32                     flavor = pseudoflavor_to_flavor(pseudoflavor);
185
186         auth = ERR_PTR(-EINVAL);
187         if (flavor >= RPC_AUTH_MAXFLAVOR)
188                 goto out;
189
190         if ((ops = auth_flavors[flavor]) == NULL)
191                 request_module("rpc-auth-%u", flavor);
192         spin_lock(&rpc_authflavor_lock);
193         ops = auth_flavors[flavor];
194         if (ops == NULL || !try_module_get(ops->owner)) {
195                 spin_unlock(&rpc_authflavor_lock);
196                 goto out;
197         }
198         spin_unlock(&rpc_authflavor_lock);
199         auth = ops->create(clnt, pseudoflavor);
200         module_put(ops->owner);
201         if (IS_ERR(auth))
202                 return auth;
203         if (clnt->cl_auth)
204                 rpcauth_release(clnt->cl_auth);
205         clnt->cl_auth = auth;
206
207 out:
208         return auth;
209 }
210 EXPORT_SYMBOL_GPL(rpcauth_create);
211
212 void
213 rpcauth_release(struct rpc_auth *auth)
214 {
215         if (!atomic_dec_and_test(&auth->au_count))
216                 return;
217         auth->au_ops->destroy(auth);
218 }
219
220 static DEFINE_SPINLOCK(rpc_credcache_lock);
221
222 static void
223 rpcauth_unhash_cred_locked(struct rpc_cred *cred)
224 {
225         hlist_del_rcu(&cred->cr_hash);
226         smp_mb__before_clear_bit();
227         clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
228 }
229
230 static int
231 rpcauth_unhash_cred(struct rpc_cred *cred)
232 {
233         spinlock_t *cache_lock;
234         int ret;
235
236         cache_lock = &cred->cr_auth->au_credcache->lock;
237         spin_lock(cache_lock);
238         ret = atomic_read(&cred->cr_count) == 0;
239         if (ret)
240                 rpcauth_unhash_cred_locked(cred);
241         spin_unlock(cache_lock);
242         return ret;
243 }
244
245 /*
246  * Initialize RPC credential cache
247  */
248 int
249 rpcauth_init_credcache(struct rpc_auth *auth)
250 {
251         struct rpc_cred_cache *new;
252         unsigned int hashsize;
253
254         new = kmalloc(sizeof(*new), GFP_KERNEL);
255         if (!new)
256                 goto out_nocache;
257         new->hashbits = auth_hashbits;
258         hashsize = 1U << new->hashbits;
259         new->hashtable = kcalloc(hashsize, sizeof(new->hashtable[0]), GFP_KERNEL);
260         if (!new->hashtable)
261                 goto out_nohashtbl;
262         spin_lock_init(&new->lock);
263         auth->au_credcache = new;
264         return 0;
265 out_nohashtbl:
266         kfree(new);
267 out_nocache:
268         return -ENOMEM;
269 }
270 EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
271
272 /*
273  * Destroy a list of credentials
274  */
275 static inline
276 void rpcauth_destroy_credlist(struct list_head *head)
277 {
278         struct rpc_cred *cred;
279
280         while (!list_empty(head)) {
281                 cred = list_entry(head->next, struct rpc_cred, cr_lru);
282                 list_del_init(&cred->cr_lru);
283                 put_rpccred(cred);
284         }
285 }
286
287 /*
288  * Clear the RPC credential cache, and delete those credentials
289  * that are not referenced.
290  */
291 void
292 rpcauth_clear_credcache(struct rpc_cred_cache *cache)
293 {
294         LIST_HEAD(free);
295         struct hlist_head *head;
296         struct rpc_cred *cred;
297         unsigned int hashsize = 1U << cache->hashbits;
298         int             i;
299
300         spin_lock(&rpc_credcache_lock);
301         spin_lock(&cache->lock);
302         for (i = 0; i < hashsize; i++) {
303                 head = &cache->hashtable[i];
304                 while (!hlist_empty(head)) {
305                         cred = hlist_entry(head->first, struct rpc_cred, cr_hash);
306                         get_rpccred(cred);
307                         if (!list_empty(&cred->cr_lru)) {
308                                 list_del(&cred->cr_lru);
309                                 number_cred_unused--;
310                         }
311                         list_add_tail(&cred->cr_lru, &free);
312                         rpcauth_unhash_cred_locked(cred);
313                 }
314         }
315         spin_unlock(&cache->lock);
316         spin_unlock(&rpc_credcache_lock);
317         rpcauth_destroy_credlist(&free);
318 }
319
320 /*
321  * Destroy the RPC credential cache
322  */
323 void
324 rpcauth_destroy_credcache(struct rpc_auth *auth)
325 {
326         struct rpc_cred_cache *cache = auth->au_credcache;
327
328         if (cache) {
329                 auth->au_credcache = NULL;
330                 rpcauth_clear_credcache(cache);
331                 kfree(cache->hashtable);
332                 kfree(cache);
333         }
334 }
335 EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
336
337
338 #define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ)
339
340 /*
341  * Remove stale credentials. Avoid sleeping inside the loop.
342  */
343 static int
344 rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
345 {
346         spinlock_t *cache_lock;
347         struct rpc_cred *cred, *next;
348         unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
349
350         list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) {
351
352                 if (nr_to_scan-- == 0)
353                         break;
354                 /*
355                  * Enforce a 60 second garbage collection moratorium
356                  * Note that the cred_unused list must be time-ordered.
357                  */
358                 if (time_in_range(cred->cr_expire, expired, jiffies) &&
359                     test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0)
360                         return 0;
361
362                 list_del_init(&cred->cr_lru);
363                 number_cred_unused--;
364                 if (atomic_read(&cred->cr_count) != 0)
365                         continue;
366
367                 cache_lock = &cred->cr_auth->au_credcache->lock;
368                 spin_lock(cache_lock);
369                 if (atomic_read(&cred->cr_count) == 0) {
370                         get_rpccred(cred);
371                         list_add_tail(&cred->cr_lru, free);
372                         rpcauth_unhash_cred_locked(cred);
373                 }
374                 spin_unlock(cache_lock);
375         }
376         return (number_cred_unused / 100) * sysctl_vfs_cache_pressure;
377 }
378
379 /*
380  * Run memory cache shrinker.
381  */
382 static int
383 rpcauth_cache_shrinker(struct shrinker *shrink, struct shrink_control *sc)
384 {
385         LIST_HEAD(free);
386         int res;
387         int nr_to_scan = sc->nr_to_scan;
388         gfp_t gfp_mask = sc->gfp_mask;
389
390         if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
391                 return (nr_to_scan == 0) ? 0 : -1;
392         if (list_empty(&cred_unused))
393                 return 0;
394         spin_lock(&rpc_credcache_lock);
395         res = rpcauth_prune_expired(&free, nr_to_scan);
396         spin_unlock(&rpc_credcache_lock);
397         rpcauth_destroy_credlist(&free);
398         return res;
399 }
400
401 /*
402  * Look up a process' credentials in the authentication cache
403  */
404 struct rpc_cred *
405 rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
406                 int flags)
407 {
408         LIST_HEAD(free);
409         struct rpc_cred_cache *cache = auth->au_credcache;
410         struct hlist_node *pos;
411         struct rpc_cred *cred = NULL,
412                         *entry, *new;
413         unsigned int nr;
414
415         nr = hash_long(from_kuid(&init_user_ns, acred->uid), cache->hashbits);
416
417         rcu_read_lock();
418         hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) {
419                 if (!entry->cr_ops->crmatch(acred, entry, flags))
420                         continue;
421                 spin_lock(&cache->lock);
422                 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
423                         spin_unlock(&cache->lock);
424                         continue;
425                 }
426                 cred = get_rpccred(entry);
427                 spin_unlock(&cache->lock);
428                 break;
429         }
430         rcu_read_unlock();
431
432         if (cred != NULL)
433                 goto found;
434
435         new = auth->au_ops->crcreate(auth, acred, flags);
436         if (IS_ERR(new)) {
437                 cred = new;
438                 goto out;
439         }
440
441         spin_lock(&cache->lock);
442         hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) {
443                 if (!entry->cr_ops->crmatch(acred, entry, flags))
444                         continue;
445                 cred = get_rpccred(entry);
446                 break;
447         }
448         if (cred == NULL) {
449                 cred = new;
450                 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
451                 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
452         } else
453                 list_add_tail(&new->cr_lru, &free);
454         spin_unlock(&cache->lock);
455 found:
456         if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
457             cred->cr_ops->cr_init != NULL &&
458             !(flags & RPCAUTH_LOOKUP_NEW)) {
459                 int res = cred->cr_ops->cr_init(auth, cred);
460                 if (res < 0) {
461                         put_rpccred(cred);
462                         cred = ERR_PTR(res);
463                 }
464         }
465         rpcauth_destroy_credlist(&free);
466 out:
467         return cred;
468 }
469 EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
470
471 struct rpc_cred *
472 rpcauth_lookupcred(struct rpc_auth *auth, int flags)
473 {
474         struct auth_cred acred;
475         struct rpc_cred *ret;
476         const struct cred *cred = current_cred();
477
478         dprintk("RPC:       looking up %s cred\n",
479                 auth->au_ops->au_name);
480
481         memset(&acred, 0, sizeof(acred));
482         acred.uid = cred->fsuid;
483         acred.gid = cred->fsgid;
484         acred.group_info = get_group_info(((struct cred *)cred)->group_info);
485
486         ret = auth->au_ops->lookup_cred(auth, &acred, flags);
487         put_group_info(acred.group_info);
488         return ret;
489 }
490
491 void
492 rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
493                   struct rpc_auth *auth, const struct rpc_credops *ops)
494 {
495         INIT_HLIST_NODE(&cred->cr_hash);
496         INIT_LIST_HEAD(&cred->cr_lru);
497         atomic_set(&cred->cr_count, 1);
498         cred->cr_auth = auth;
499         cred->cr_ops = ops;
500         cred->cr_expire = jiffies;
501 #ifdef RPC_DEBUG
502         cred->cr_magic = RPCAUTH_CRED_MAGIC;
503 #endif
504         cred->cr_uid = acred->uid;
505 }
506 EXPORT_SYMBOL_GPL(rpcauth_init_cred);
507
508 struct rpc_cred *
509 rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags)
510 {
511         dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid,
512                         cred->cr_auth->au_ops->au_name, cred);
513         return get_rpccred(cred);
514 }
515 EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred);
516
517 static struct rpc_cred *
518 rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags)
519 {
520         struct rpc_auth *auth = task->tk_client->cl_auth;
521         struct auth_cred acred = {
522                 .uid = GLOBAL_ROOT_UID,
523                 .gid = GLOBAL_ROOT_GID,
524         };
525
526         dprintk("RPC: %5u looking up %s cred\n",
527                 task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
528         return auth->au_ops->lookup_cred(auth, &acred, lookupflags);
529 }
530
531 static struct rpc_cred *
532 rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags)
533 {
534         struct rpc_auth *auth = task->tk_client->cl_auth;
535
536         dprintk("RPC: %5u looking up %s cred\n",
537                 task->tk_pid, auth->au_ops->au_name);
538         return rpcauth_lookupcred(auth, lookupflags);
539 }
540
541 static int
542 rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags)
543 {
544         struct rpc_rqst *req = task->tk_rqstp;
545         struct rpc_cred *new;
546         int lookupflags = 0;
547
548         if (flags & RPC_TASK_ASYNC)
549                 lookupflags |= RPCAUTH_LOOKUP_NEW;
550         if (cred != NULL)
551                 new = cred->cr_ops->crbind(task, cred, lookupflags);
552         else if (flags & RPC_TASK_ROOTCREDS)
553                 new = rpcauth_bind_root_cred(task, lookupflags);
554         else
555                 new = rpcauth_bind_new_cred(task, lookupflags);
556         if (IS_ERR(new))
557                 return PTR_ERR(new);
558         if (req->rq_cred != NULL)
559                 put_rpccred(req->rq_cred);
560         req->rq_cred = new;
561         return 0;
562 }
563
564 void
565 put_rpccred(struct rpc_cred *cred)
566 {
567         /* Fast path for unhashed credentials */
568         if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) {
569                 if (atomic_dec_and_test(&cred->cr_count))
570                         cred->cr_ops->crdestroy(cred);
571                 return;
572         }
573
574         if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
575                 return;
576         if (!list_empty(&cred->cr_lru)) {
577                 number_cred_unused--;
578                 list_del_init(&cred->cr_lru);
579         }
580         if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
581                 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) {
582                         cred->cr_expire = jiffies;
583                         list_add_tail(&cred->cr_lru, &cred_unused);
584                         number_cred_unused++;
585                         goto out_nodestroy;
586                 }
587                 if (!rpcauth_unhash_cred(cred)) {
588                         /* We were hashed and someone looked us up... */
589                         goto out_nodestroy;
590                 }
591         }
592         spin_unlock(&rpc_credcache_lock);
593         cred->cr_ops->crdestroy(cred);
594         return;
595 out_nodestroy:
596         spin_unlock(&rpc_credcache_lock);
597 }
598 EXPORT_SYMBOL_GPL(put_rpccred);
599
600 __be32 *
601 rpcauth_marshcred(struct rpc_task *task, __be32 *p)
602 {
603         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
604
605         dprintk("RPC: %5u marshaling %s cred %p\n",
606                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
607
608         return cred->cr_ops->crmarshal(task, p);
609 }
610
611 __be32 *
612 rpcauth_checkverf(struct rpc_task *task, __be32 *p)
613 {
614         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
615
616         dprintk("RPC: %5u validating %s cred %p\n",
617                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
618
619         return cred->cr_ops->crvalidate(task, p);
620 }
621
622 static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
623                                    __be32 *data, void *obj)
624 {
625         struct xdr_stream xdr;
626
627         xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data);
628         encode(rqstp, &xdr, obj);
629 }
630
631 int
632 rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp,
633                 __be32 *data, void *obj)
634 {
635         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
636
637         dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
638                         task->tk_pid, cred->cr_ops->cr_name, cred);
639         if (cred->cr_ops->crwrap_req)
640                 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
641         /* By default, we encode the arguments normally. */
642         rpcauth_wrap_req_encode(encode, rqstp, data, obj);
643         return 0;
644 }
645
646 static int
647 rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
648                           __be32 *data, void *obj)
649 {
650         struct xdr_stream xdr;
651
652         xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data);
653         return decode(rqstp, &xdr, obj);
654 }
655
656 int
657 rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp,
658                 __be32 *data, void *obj)
659 {
660         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
661
662         dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
663                         task->tk_pid, cred->cr_ops->cr_name, cred);
664         if (cred->cr_ops->crunwrap_resp)
665                 return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
666                                                    data, obj);
667         /* By default, we decode the arguments normally. */
668         return rpcauth_unwrap_req_decode(decode, rqstp, data, obj);
669 }
670
671 int
672 rpcauth_refreshcred(struct rpc_task *task)
673 {
674         struct rpc_cred *cred;
675         int err;
676
677         cred = task->tk_rqstp->rq_cred;
678         if (cred == NULL) {
679                 err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags);
680                 if (err < 0)
681                         goto out;
682                 cred = task->tk_rqstp->rq_cred;
683         }
684         dprintk("RPC: %5u refreshing %s cred %p\n",
685                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
686
687         err = cred->cr_ops->crrefresh(task);
688 out:
689         if (err < 0)
690                 task->tk_status = err;
691         return err;
692 }
693
694 void
695 rpcauth_invalcred(struct rpc_task *task)
696 {
697         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
698
699         dprintk("RPC: %5u invalidating %s cred %p\n",
700                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
701         if (cred)
702                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
703 }
704
705 int
706 rpcauth_uptodatecred(struct rpc_task *task)
707 {
708         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
709
710         return cred == NULL ||
711                 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
712 }
713
714 static struct shrinker rpc_cred_shrinker = {
715         .shrink = rpcauth_cache_shrinker,
716         .seeks = DEFAULT_SEEKS,
717 };
718
719 int __init rpcauth_init_module(void)
720 {
721         int err;
722
723         err = rpc_init_authunix();
724         if (err < 0)
725                 goto out1;
726         err = rpc_init_generic_auth();
727         if (err < 0)
728                 goto out2;
729         register_shrinker(&rpc_cred_shrinker);
730         return 0;
731 out2:
732         rpc_destroy_authunix();
733 out1:
734         return err;
735 }
736
737 void rpcauth_remove_module(void)
738 {
739         rpc_destroy_authunix();
740         rpc_destroy_generic_auth();
741         unregister_shrinker(&rpc_cred_shrinker);
742 }