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)
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 DEFINE_SPINLOCK(rpc_authflavor_lock);
33static 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
39static LIST_HEAD(cred_unused);
40static unsigned long number_cred_unused;
41
42#define MAX_HASHTABLE_BITS (14)
43static 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;
61out_inval:
62	return -EINVAL;
63}
64
65static 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
75static struct kernel_param_ops param_ops_hashtbl_sz = {
76	.set = param_set_hashtbl_sz,
77	.get = param_get_hashtbl_sz,
78};
79
80module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644);
81MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size");
82
83static u32
84pseudoflavor_to_flavor(u32 flavor) {
85	if (flavor > RPC_AUTH_MAXFLAVOR)
86		return RPC_AUTH_GSS;
87	return flavor;
88}
89
90int
91rpcauth_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}
106EXPORT_SYMBOL_GPL(rpcauth_register);
107
108int
109rpcauth_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}
124EXPORT_SYMBOL_GPL(rpcauth_unregister);
125
126/**
127 * rpcauth_get_pseudoflavor - check if security flavor is supported
128 * @flavor: a security flavor
129 * @info: a GSS mech OID, quality of protection, and service value
130 *
131 * Verifies that an appropriate kernel module is available or already loaded.
132 * Returns an equivalent pseudoflavor, or RPC_AUTH_MAXFLAVOR if "flavor" is
133 * not supported locally.
134 */
135rpc_authflavor_t
136rpcauth_get_pseudoflavor(rpc_authflavor_t flavor, struct rpcsec_gss_info *info)
137{
138	const struct rpc_authops *ops;
139	rpc_authflavor_t pseudoflavor;
140
141	ops = auth_flavors[flavor];
142	if (ops == NULL)
143		request_module("rpc-auth-%u", flavor);
144	spin_lock(&rpc_authflavor_lock);
145	ops = auth_flavors[flavor];
146	if (ops == NULL || !try_module_get(ops->owner)) {
147		spin_unlock(&rpc_authflavor_lock);
148		return RPC_AUTH_MAXFLAVOR;
149	}
150	spin_unlock(&rpc_authflavor_lock);
151
152	pseudoflavor = flavor;
153	if (ops->info2flavor != NULL)
154		pseudoflavor = ops->info2flavor(info);
155
156	module_put(ops->owner);
157	return pseudoflavor;
158}
159EXPORT_SYMBOL_GPL(rpcauth_get_pseudoflavor);
160
161/**
162 * rpcauth_get_gssinfo - find GSS tuple matching a GSS pseudoflavor
163 * @pseudoflavor: GSS pseudoflavor to match
164 * @info: rpcsec_gss_info structure to fill in
165 *
166 * Returns zero and fills in "info" if pseudoflavor matches a
167 * supported mechanism.
168 */
169int
170rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info)
171{
172	rpc_authflavor_t flavor = pseudoflavor_to_flavor(pseudoflavor);
173	const struct rpc_authops *ops;
174	int result;
175
176	if (flavor >= RPC_AUTH_MAXFLAVOR)
177		return -EINVAL;
178
179	ops = auth_flavors[flavor];
180	if (ops == NULL)
181		request_module("rpc-auth-%u", flavor);
182	spin_lock(&rpc_authflavor_lock);
183	ops = auth_flavors[flavor];
184	if (ops == NULL || !try_module_get(ops->owner)) {
185		spin_unlock(&rpc_authflavor_lock);
186		return -ENOENT;
187	}
188	spin_unlock(&rpc_authflavor_lock);
189
190	result = -ENOENT;
191	if (ops->flavor2info != NULL)
192		result = ops->flavor2info(pseudoflavor, info);
193
194	module_put(ops->owner);
195	return result;
196}
197EXPORT_SYMBOL_GPL(rpcauth_get_gssinfo);
198
199/**
200 * rpcauth_list_flavors - discover registered flavors and pseudoflavors
201 * @array: array to fill in
202 * @size: size of "array"
203 *
204 * Returns the number of array items filled in, or a negative errno.
205 *
206 * The returned array is not sorted by any policy.  Callers should not
207 * rely on the order of the items in the returned array.
208 */
209int
210rpcauth_list_flavors(rpc_authflavor_t *array, int size)
211{
212	rpc_authflavor_t flavor;
213	int result = 0;
214
215	spin_lock(&rpc_authflavor_lock);
216	for (flavor = 0; flavor < RPC_AUTH_MAXFLAVOR; flavor++) {
217		const struct rpc_authops *ops = auth_flavors[flavor];
218		rpc_authflavor_t pseudos[4];
219		int i, len;
220
221		if (result >= size) {
222			result = -ENOMEM;
223			break;
224		}
225
226		if (ops == NULL)
227			continue;
228		if (ops->list_pseudoflavors == NULL) {
229			array[result++] = ops->au_flavor;
230			continue;
231		}
232		len = ops->list_pseudoflavors(pseudos, ARRAY_SIZE(pseudos));
233		if (len < 0) {
234			result = len;
235			break;
236		}
237		for (i = 0; i < len; i++) {
238			if (result >= size) {
239				result = -ENOMEM;
240				break;
241			}
242			array[result++] = pseudos[i];
243		}
244	}
245	spin_unlock(&rpc_authflavor_lock);
246
247	dprintk("RPC:       %s returns %d\n", __func__, result);
248	return result;
249}
250EXPORT_SYMBOL_GPL(rpcauth_list_flavors);
251
252struct rpc_auth *
253rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
254{
255	struct rpc_auth		*auth;
256	const struct rpc_authops *ops;
257	u32			flavor = pseudoflavor_to_flavor(pseudoflavor);
258
259	auth = ERR_PTR(-EINVAL);
260	if (flavor >= RPC_AUTH_MAXFLAVOR)
261		goto out;
262
263	if ((ops = auth_flavors[flavor]) == NULL)
264		request_module("rpc-auth-%u", flavor);
265	spin_lock(&rpc_authflavor_lock);
266	ops = auth_flavors[flavor];
267	if (ops == NULL || !try_module_get(ops->owner)) {
268		spin_unlock(&rpc_authflavor_lock);
269		goto out;
270	}
271	spin_unlock(&rpc_authflavor_lock);
272	auth = ops->create(clnt, pseudoflavor);
273	module_put(ops->owner);
274	if (IS_ERR(auth))
275		return auth;
276	if (clnt->cl_auth)
277		rpcauth_release(clnt->cl_auth);
278	clnt->cl_auth = auth;
279
280out:
281	return auth;
282}
283EXPORT_SYMBOL_GPL(rpcauth_create);
284
285void
286rpcauth_release(struct rpc_auth *auth)
287{
288	if (!atomic_dec_and_test(&auth->au_count))
289		return;
290	auth->au_ops->destroy(auth);
291}
292
293static DEFINE_SPINLOCK(rpc_credcache_lock);
294
295static void
296rpcauth_unhash_cred_locked(struct rpc_cred *cred)
297{
298	hlist_del_rcu(&cred->cr_hash);
299	smp_mb__before_clear_bit();
300	clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
301}
302
303static int
304rpcauth_unhash_cred(struct rpc_cred *cred)
305{
306	spinlock_t *cache_lock;
307	int ret;
308
309	cache_lock = &cred->cr_auth->au_credcache->lock;
310	spin_lock(cache_lock);
311	ret = atomic_read(&cred->cr_count) == 0;
312	if (ret)
313		rpcauth_unhash_cred_locked(cred);
314	spin_unlock(cache_lock);
315	return ret;
316}
317
318/*
319 * Initialize RPC credential cache
320 */
321int
322rpcauth_init_credcache(struct rpc_auth *auth)
323{
324	struct rpc_cred_cache *new;
325	unsigned int hashsize;
326
327	new = kmalloc(sizeof(*new), GFP_KERNEL);
328	if (!new)
329		goto out_nocache;
330	new->hashbits = auth_hashbits;
331	hashsize = 1U << new->hashbits;
332	new->hashtable = kcalloc(hashsize, sizeof(new->hashtable[0]), GFP_KERNEL);
333	if (!new->hashtable)
334		goto out_nohashtbl;
335	spin_lock_init(&new->lock);
336	auth->au_credcache = new;
337	return 0;
338out_nohashtbl:
339	kfree(new);
340out_nocache:
341	return -ENOMEM;
342}
343EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
344
345/*
346 * Destroy a list of credentials
347 */
348static inline
349void rpcauth_destroy_credlist(struct list_head *head)
350{
351	struct rpc_cred *cred;
352
353	while (!list_empty(head)) {
354		cred = list_entry(head->next, struct rpc_cred, cr_lru);
355		list_del_init(&cred->cr_lru);
356		put_rpccred(cred);
357	}
358}
359
360/*
361 * Clear the RPC credential cache, and delete those credentials
362 * that are not referenced.
363 */
364void
365rpcauth_clear_credcache(struct rpc_cred_cache *cache)
366{
367	LIST_HEAD(free);
368	struct hlist_head *head;
369	struct rpc_cred	*cred;
370	unsigned int hashsize = 1U << cache->hashbits;
371	int		i;
372
373	spin_lock(&rpc_credcache_lock);
374	spin_lock(&cache->lock);
375	for (i = 0; i < hashsize; i++) {
376		head = &cache->hashtable[i];
377		while (!hlist_empty(head)) {
378			cred = hlist_entry(head->first, struct rpc_cred, cr_hash);
379			get_rpccred(cred);
380			if (!list_empty(&cred->cr_lru)) {
381				list_del(&cred->cr_lru);
382				number_cred_unused--;
383			}
384			list_add_tail(&cred->cr_lru, &free);
385			rpcauth_unhash_cred_locked(cred);
386		}
387	}
388	spin_unlock(&cache->lock);
389	spin_unlock(&rpc_credcache_lock);
390	rpcauth_destroy_credlist(&free);
391}
392
393/*
394 * Destroy the RPC credential cache
395 */
396void
397rpcauth_destroy_credcache(struct rpc_auth *auth)
398{
399	struct rpc_cred_cache *cache = auth->au_credcache;
400
401	if (cache) {
402		auth->au_credcache = NULL;
403		rpcauth_clear_credcache(cache);
404		kfree(cache->hashtable);
405		kfree(cache);
406	}
407}
408EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
409
410
411#define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ)
412
413/*
414 * Remove stale credentials. Avoid sleeping inside the loop.
415 */
416static int
417rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
418{
419	spinlock_t *cache_lock;
420	struct rpc_cred *cred, *next;
421	unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
422
423	list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) {
424
425		if (nr_to_scan-- == 0)
426			break;
427		/*
428		 * Enforce a 60 second garbage collection moratorium
429		 * Note that the cred_unused list must be time-ordered.
430		 */
431		if (time_in_range(cred->cr_expire, expired, jiffies) &&
432		    test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0)
433			return 0;
434
435		list_del_init(&cred->cr_lru);
436		number_cred_unused--;
437		if (atomic_read(&cred->cr_count) != 0)
438			continue;
439
440		cache_lock = &cred->cr_auth->au_credcache->lock;
441		spin_lock(cache_lock);
442		if (atomic_read(&cred->cr_count) == 0) {
443			get_rpccred(cred);
444			list_add_tail(&cred->cr_lru, free);
445			rpcauth_unhash_cred_locked(cred);
446		}
447		spin_unlock(cache_lock);
448	}
449	return (number_cred_unused / 100) * sysctl_vfs_cache_pressure;
450}
451
452/*
453 * Run memory cache shrinker.
454 */
455static int
456rpcauth_cache_shrinker(struct shrinker *shrink, struct shrink_control *sc)
457{
458	LIST_HEAD(free);
459	int res;
460	int nr_to_scan = sc->nr_to_scan;
461	gfp_t gfp_mask = sc->gfp_mask;
462
463	if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
464		return (nr_to_scan == 0) ? 0 : -1;
465	if (list_empty(&cred_unused))
466		return 0;
467	spin_lock(&rpc_credcache_lock);
468	res = rpcauth_prune_expired(&free, nr_to_scan);
469	spin_unlock(&rpc_credcache_lock);
470	rpcauth_destroy_credlist(&free);
471	return res;
472}
473
474/*
475 * Look up a process' credentials in the authentication cache
476 */
477struct rpc_cred *
478rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
479		int flags)
480{
481	LIST_HEAD(free);
482	struct rpc_cred_cache *cache = auth->au_credcache;
483	struct rpc_cred	*cred = NULL,
484			*entry, *new;
485	unsigned int nr;
486
487	nr = hash_long(from_kuid(&init_user_ns, acred->uid), cache->hashbits);
488
489	rcu_read_lock();
490	hlist_for_each_entry_rcu(entry, &cache->hashtable[nr], cr_hash) {
491		if (!entry->cr_ops->crmatch(acred, entry, flags))
492			continue;
493		spin_lock(&cache->lock);
494		if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
495			spin_unlock(&cache->lock);
496			continue;
497		}
498		cred = get_rpccred(entry);
499		spin_unlock(&cache->lock);
500		break;
501	}
502	rcu_read_unlock();
503
504	if (cred != NULL)
505		goto found;
506
507	new = auth->au_ops->crcreate(auth, acred, flags);
508	if (IS_ERR(new)) {
509		cred = new;
510		goto out;
511	}
512
513	spin_lock(&cache->lock);
514	hlist_for_each_entry(entry, &cache->hashtable[nr], cr_hash) {
515		if (!entry->cr_ops->crmatch(acred, entry, flags))
516			continue;
517		cred = get_rpccred(entry);
518		break;
519	}
520	if (cred == NULL) {
521		cred = new;
522		set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
523		hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
524	} else
525		list_add_tail(&new->cr_lru, &free);
526	spin_unlock(&cache->lock);
527found:
528	if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
529	    cred->cr_ops->cr_init != NULL &&
530	    !(flags & RPCAUTH_LOOKUP_NEW)) {
531		int res = cred->cr_ops->cr_init(auth, cred);
532		if (res < 0) {
533			put_rpccred(cred);
534			cred = ERR_PTR(res);
535		}
536	}
537	rpcauth_destroy_credlist(&free);
538out:
539	return cred;
540}
541EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
542
543struct rpc_cred *
544rpcauth_lookupcred(struct rpc_auth *auth, int flags)
545{
546	struct auth_cred acred;
547	struct rpc_cred *ret;
548	const struct cred *cred = current_cred();
549
550	dprintk("RPC:       looking up %s cred\n",
551		auth->au_ops->au_name);
552
553	memset(&acred, 0, sizeof(acred));
554	acred.uid = cred->fsuid;
555	acred.gid = cred->fsgid;
556	acred.group_info = get_group_info(((struct cred *)cred)->group_info);
557
558	ret = auth->au_ops->lookup_cred(auth, &acred, flags);
559	put_group_info(acred.group_info);
560	return ret;
561}
562
563void
564rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
565		  struct rpc_auth *auth, const struct rpc_credops *ops)
566{
567	INIT_HLIST_NODE(&cred->cr_hash);
568	INIT_LIST_HEAD(&cred->cr_lru);
569	atomic_set(&cred->cr_count, 1);
570	cred->cr_auth = auth;
571	cred->cr_ops = ops;
572	cred->cr_expire = jiffies;
573#ifdef RPC_DEBUG
574	cred->cr_magic = RPCAUTH_CRED_MAGIC;
575#endif
576	cred->cr_uid = acred->uid;
577}
578EXPORT_SYMBOL_GPL(rpcauth_init_cred);
579
580struct rpc_cred *
581rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags)
582{
583	dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid,
584			cred->cr_auth->au_ops->au_name, cred);
585	return get_rpccred(cred);
586}
587EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred);
588
589static struct rpc_cred *
590rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags)
591{
592	struct rpc_auth *auth = task->tk_client->cl_auth;
593	struct auth_cred acred = {
594		.uid = GLOBAL_ROOT_UID,
595		.gid = GLOBAL_ROOT_GID,
596	};
597
598	dprintk("RPC: %5u looking up %s cred\n",
599		task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
600	return auth->au_ops->lookup_cred(auth, &acred, lookupflags);
601}
602
603static struct rpc_cred *
604rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags)
605{
606	struct rpc_auth *auth = task->tk_client->cl_auth;
607
608	dprintk("RPC: %5u looking up %s cred\n",
609		task->tk_pid, auth->au_ops->au_name);
610	return rpcauth_lookupcred(auth, lookupflags);
611}
612
613static int
614rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags)
615{
616	struct rpc_rqst *req = task->tk_rqstp;
617	struct rpc_cred *new;
618	int lookupflags = 0;
619
620	if (flags & RPC_TASK_ASYNC)
621		lookupflags |= RPCAUTH_LOOKUP_NEW;
622	if (cred != NULL)
623		new = cred->cr_ops->crbind(task, cred, lookupflags);
624	else if (flags & RPC_TASK_ROOTCREDS)
625		new = rpcauth_bind_root_cred(task, lookupflags);
626	else
627		new = rpcauth_bind_new_cred(task, lookupflags);
628	if (IS_ERR(new))
629		return PTR_ERR(new);
630	if (req->rq_cred != NULL)
631		put_rpccred(req->rq_cred);
632	req->rq_cred = new;
633	return 0;
634}
635
636void
637put_rpccred(struct rpc_cred *cred)
638{
639	/* Fast path for unhashed credentials */
640	if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) {
641		if (atomic_dec_and_test(&cred->cr_count))
642			cred->cr_ops->crdestroy(cred);
643		return;
644	}
645
646	if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
647		return;
648	if (!list_empty(&cred->cr_lru)) {
649		number_cred_unused--;
650		list_del_init(&cred->cr_lru);
651	}
652	if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
653		if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) {
654			cred->cr_expire = jiffies;
655			list_add_tail(&cred->cr_lru, &cred_unused);
656			number_cred_unused++;
657			goto out_nodestroy;
658		}
659		if (!rpcauth_unhash_cred(cred)) {
660			/* We were hashed and someone looked us up... */
661			goto out_nodestroy;
662		}
663	}
664	spin_unlock(&rpc_credcache_lock);
665	cred->cr_ops->crdestroy(cred);
666	return;
667out_nodestroy:
668	spin_unlock(&rpc_credcache_lock);
669}
670EXPORT_SYMBOL_GPL(put_rpccred);
671
672__be32 *
673rpcauth_marshcred(struct rpc_task *task, __be32 *p)
674{
675	struct rpc_cred	*cred = task->tk_rqstp->rq_cred;
676
677	dprintk("RPC: %5u marshaling %s cred %p\n",
678		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
679
680	return cred->cr_ops->crmarshal(task, p);
681}
682
683__be32 *
684rpcauth_checkverf(struct rpc_task *task, __be32 *p)
685{
686	struct rpc_cred	*cred = task->tk_rqstp->rq_cred;
687
688	dprintk("RPC: %5u validating %s cred %p\n",
689		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
690
691	return cred->cr_ops->crvalidate(task, p);
692}
693
694static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
695				   __be32 *data, void *obj)
696{
697	struct xdr_stream xdr;
698
699	xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data);
700	encode(rqstp, &xdr, obj);
701}
702
703int
704rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp,
705		__be32 *data, void *obj)
706{
707	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
708
709	dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
710			task->tk_pid, cred->cr_ops->cr_name, cred);
711	if (cred->cr_ops->crwrap_req)
712		return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
713	/* By default, we encode the arguments normally. */
714	rpcauth_wrap_req_encode(encode, rqstp, data, obj);
715	return 0;
716}
717
718static int
719rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
720			  __be32 *data, void *obj)
721{
722	struct xdr_stream xdr;
723
724	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data);
725	return decode(rqstp, &xdr, obj);
726}
727
728int
729rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp,
730		__be32 *data, void *obj)
731{
732	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
733
734	dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
735			task->tk_pid, cred->cr_ops->cr_name, cred);
736	if (cred->cr_ops->crunwrap_resp)
737		return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
738						   data, obj);
739	/* By default, we decode the arguments normally. */
740	return rpcauth_unwrap_req_decode(decode, rqstp, data, obj);
741}
742
743int
744rpcauth_refreshcred(struct rpc_task *task)
745{
746	struct rpc_cred	*cred;
747	int err;
748
749	cred = task->tk_rqstp->rq_cred;
750	if (cred == NULL) {
751		err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags);
752		if (err < 0)
753			goto out;
754		cred = task->tk_rqstp->rq_cred;
755	}
756	dprintk("RPC: %5u refreshing %s cred %p\n",
757		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
758
759	err = cred->cr_ops->crrefresh(task);
760out:
761	if (err < 0)
762		task->tk_status = err;
763	return err;
764}
765
766void
767rpcauth_invalcred(struct rpc_task *task)
768{
769	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
770
771	dprintk("RPC: %5u invalidating %s cred %p\n",
772		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
773	if (cred)
774		clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
775}
776
777int
778rpcauth_uptodatecred(struct rpc_task *task)
779{
780	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
781
782	return cred == NULL ||
783		test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
784}
785
786static struct shrinker rpc_cred_shrinker = {
787	.shrink = rpcauth_cache_shrinker,
788	.seeks = DEFAULT_SEEKS,
789};
790
791int __init rpcauth_init_module(void)
792{
793	int err;
794
795	err = rpc_init_authunix();
796	if (err < 0)
797		goto out1;
798	err = rpc_init_generic_auth();
799	if (err < 0)
800		goto out2;
801	register_shrinker(&rpc_cred_shrinker);
802	return 0;
803out2:
804	rpc_destroy_authunix();
805out1:
806	return err;
807}
808
809void rpcauth_remove_module(void)
810{
811	rpc_destroy_authunix();
812	rpc_destroy_generic_auth();
813	unregister_shrinker(&rpc_cred_shrinker);
814}
815