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)
23 struct rpc_cred_cache {
24 	struct hlist_head	*hashtable;
25 	unsigned int		hashbits;
26 	spinlock_t		lock;
27 };
28 
29 static unsigned int auth_hashbits = RPC_CREDCACHE_DEFAULT_HASHBITS;
30 
31 static DEFINE_SPINLOCK(rpc_authflavor_lock);
32 static 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 
38 static LIST_HEAD(cred_unused);
39 static unsigned long number_cred_unused;
40 
41 #define MAX_HASHTABLE_BITS (14)
param_set_hashtbl_sz(const char * val,const struct kernel_param * kp)42 static 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;
60 out_inval:
61 	return -EINVAL;
62 }
63 
param_get_hashtbl_sz(char * buffer,const struct kernel_param * kp)64 static 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 
74 static struct kernel_param_ops param_ops_hashtbl_sz = {
75 	.set = param_set_hashtbl_sz,
76 	.get = param_get_hashtbl_sz,
77 };
78 
79 module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644);
80 MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size");
81 
82 static u32
pseudoflavor_to_flavor(u32 flavor)83 pseudoflavor_to_flavor(u32 flavor) {
84 	if (flavor >= RPC_AUTH_MAXFLAVOR)
85 		return RPC_AUTH_GSS;
86 	return flavor;
87 }
88 
89 int
rpcauth_register(const struct rpc_authops * ops)90 rpcauth_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 }
105 EXPORT_SYMBOL_GPL(rpcauth_register);
106 
107 int
rpcauth_unregister(const struct rpc_authops * ops)108 rpcauth_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 }
123 EXPORT_SYMBOL_GPL(rpcauth_unregister);
124 
125 struct rpc_auth *
rpcauth_create(rpc_authflavor_t pseudoflavor,struct rpc_clnt * clnt)126 rpcauth_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 
153 out:
154 	return auth;
155 }
156 EXPORT_SYMBOL_GPL(rpcauth_create);
157 
158 void
rpcauth_release(struct rpc_auth * auth)159 rpcauth_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 
166 static DEFINE_SPINLOCK(rpc_credcache_lock);
167 
168 static void
rpcauth_unhash_cred_locked(struct rpc_cred * cred)169 rpcauth_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 
176 static int
rpcauth_unhash_cred(struct rpc_cred * cred)177 rpcauth_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  */
194 int
rpcauth_init_credcache(struct rpc_auth * auth)195 rpcauth_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;
211 out_nohashtbl:
212 	kfree(new);
213 out_nocache:
214 	return -ENOMEM;
215 }
216 EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
217 
218 /*
219  * Destroy a list of credentials
220  */
221 static inline
rpcauth_destroy_credlist(struct list_head * head)222 void 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  */
237 void
rpcauth_clear_credcache(struct rpc_cred_cache * cache)238 rpcauth_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  */
269 void
rpcauth_destroy_credcache(struct rpc_auth * auth)270 rpcauth_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 }
281 EXPORT_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  */
289 static int
rpcauth_prune_expired(struct list_head * free,int nr_to_scan)290 rpcauth_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  */
328 static int
rpcauth_cache_shrinker(struct shrinker * shrink,int nr_to_scan,gfp_t gfp_mask)329 rpcauth_cache_shrinker(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
330 {
331 	LIST_HEAD(free);
332 	int res;
333 
334 	if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
335 		return (nr_to_scan == 0) ? 0 : -1;
336 	if (list_empty(&cred_unused))
337 		return 0;
338 	spin_lock(&rpc_credcache_lock);
339 	res = rpcauth_prune_expired(&free, nr_to_scan);
340 	spin_unlock(&rpc_credcache_lock);
341 	rpcauth_destroy_credlist(&free);
342 	return res;
343 }
344 
345 /*
346  * Look up a process' credentials in the authentication cache
347  */
348 struct rpc_cred *
rpcauth_lookup_credcache(struct rpc_auth * auth,struct auth_cred * acred,int flags)349 rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
350 		int flags)
351 {
352 	LIST_HEAD(free);
353 	struct rpc_cred_cache *cache = auth->au_credcache;
354 	struct hlist_node *pos;
355 	struct rpc_cred	*cred = NULL,
356 			*entry, *new;
357 	unsigned int nr;
358 
359 	nr = hash_long(acred->uid, cache->hashbits);
360 
361 	rcu_read_lock();
362 	hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) {
363 		if (!entry->cr_ops->crmatch(acred, entry, flags))
364 			continue;
365 		spin_lock(&cache->lock);
366 		if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
367 			spin_unlock(&cache->lock);
368 			continue;
369 		}
370 		cred = get_rpccred(entry);
371 		spin_unlock(&cache->lock);
372 		break;
373 	}
374 	rcu_read_unlock();
375 
376 	if (cred != NULL)
377 		goto found;
378 
379 	new = auth->au_ops->crcreate(auth, acred, flags);
380 	if (IS_ERR(new)) {
381 		cred = new;
382 		goto out;
383 	}
384 
385 	spin_lock(&cache->lock);
386 	hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) {
387 		if (!entry->cr_ops->crmatch(acred, entry, flags))
388 			continue;
389 		cred = get_rpccred(entry);
390 		break;
391 	}
392 	if (cred == NULL) {
393 		cred = new;
394 		set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
395 		hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
396 	} else
397 		list_add_tail(&new->cr_lru, &free);
398 	spin_unlock(&cache->lock);
399 found:
400 	if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
401 	    cred->cr_ops->cr_init != NULL &&
402 	    !(flags & RPCAUTH_LOOKUP_NEW)) {
403 		int res = cred->cr_ops->cr_init(auth, cred);
404 		if (res < 0) {
405 			put_rpccred(cred);
406 			cred = ERR_PTR(res);
407 		}
408 	}
409 	rpcauth_destroy_credlist(&free);
410 out:
411 	return cred;
412 }
413 EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
414 
415 struct rpc_cred *
rpcauth_lookupcred(struct rpc_auth * auth,int flags)416 rpcauth_lookupcred(struct rpc_auth *auth, int flags)
417 {
418 	struct auth_cred acred;
419 	struct rpc_cred *ret;
420 	const struct cred *cred = current_cred();
421 
422 	dprintk("RPC:       looking up %s cred\n",
423 		auth->au_ops->au_name);
424 
425 	memset(&acred, 0, sizeof(acred));
426 	acred.uid = cred->fsuid;
427 	acred.gid = cred->fsgid;
428 	acred.group_info = get_group_info(((struct cred *)cred)->group_info);
429 
430 	ret = auth->au_ops->lookup_cred(auth, &acred, flags);
431 	put_group_info(acred.group_info);
432 	return ret;
433 }
434 
435 void
rpcauth_init_cred(struct rpc_cred * cred,const struct auth_cred * acred,struct rpc_auth * auth,const struct rpc_credops * ops)436 rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
437 		  struct rpc_auth *auth, const struct rpc_credops *ops)
438 {
439 	INIT_HLIST_NODE(&cred->cr_hash);
440 	INIT_LIST_HEAD(&cred->cr_lru);
441 	atomic_set(&cred->cr_count, 1);
442 	cred->cr_auth = auth;
443 	cred->cr_ops = ops;
444 	cred->cr_expire = jiffies;
445 #ifdef RPC_DEBUG
446 	cred->cr_magic = RPCAUTH_CRED_MAGIC;
447 #endif
448 	cred->cr_uid = acred->uid;
449 }
450 EXPORT_SYMBOL_GPL(rpcauth_init_cred);
451 
452 struct rpc_cred *
rpcauth_generic_bind_cred(struct rpc_task * task,struct rpc_cred * cred,int lookupflags)453 rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags)
454 {
455 	dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid,
456 			cred->cr_auth->au_ops->au_name, cred);
457 	return get_rpccred(cred);
458 }
459 EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred);
460 
461 static struct rpc_cred *
rpcauth_bind_root_cred(struct rpc_task * task,int lookupflags)462 rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags)
463 {
464 	struct rpc_auth *auth = task->tk_client->cl_auth;
465 	struct auth_cred acred = {
466 		.uid = 0,
467 		.gid = 0,
468 	};
469 
470 	dprintk("RPC: %5u looking up %s cred\n",
471 		task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
472 	return auth->au_ops->lookup_cred(auth, &acred, lookupflags);
473 }
474 
475 static struct rpc_cred *
rpcauth_bind_new_cred(struct rpc_task * task,int lookupflags)476 rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags)
477 {
478 	struct rpc_auth *auth = task->tk_client->cl_auth;
479 
480 	dprintk("RPC: %5u looking up %s cred\n",
481 		task->tk_pid, auth->au_ops->au_name);
482 	return rpcauth_lookupcred(auth, lookupflags);
483 }
484 
485 static int
rpcauth_bindcred(struct rpc_task * task,struct rpc_cred * cred,int flags)486 rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags)
487 {
488 	struct rpc_rqst *req = task->tk_rqstp;
489 	struct rpc_cred *new;
490 	int lookupflags = 0;
491 
492 	if (flags & RPC_TASK_ASYNC)
493 		lookupflags |= RPCAUTH_LOOKUP_NEW;
494 	if (cred != NULL)
495 		new = cred->cr_ops->crbind(task, cred, lookupflags);
496 	else if (flags & RPC_TASK_ROOTCREDS)
497 		new = rpcauth_bind_root_cred(task, lookupflags);
498 	else
499 		new = rpcauth_bind_new_cred(task, lookupflags);
500 	if (IS_ERR(new))
501 		return PTR_ERR(new);
502 	if (req->rq_cred != NULL)
503 		put_rpccred(req->rq_cred);
504 	req->rq_cred = new;
505 	return 0;
506 }
507 
508 void
put_rpccred(struct rpc_cred * cred)509 put_rpccred(struct rpc_cred *cred)
510 {
511 	/* Fast path for unhashed credentials */
512 	if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) {
513 		if (atomic_dec_and_test(&cred->cr_count))
514 			cred->cr_ops->crdestroy(cred);
515 		return;
516 	}
517 
518 	if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
519 		return;
520 	if (!list_empty(&cred->cr_lru)) {
521 		number_cred_unused--;
522 		list_del_init(&cred->cr_lru);
523 	}
524 	if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
525 		if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) {
526 			cred->cr_expire = jiffies;
527 			list_add_tail(&cred->cr_lru, &cred_unused);
528 			number_cred_unused++;
529 			goto out_nodestroy;
530 		}
531 		if (!rpcauth_unhash_cred(cred)) {
532 			/* We were hashed and someone looked us up... */
533 			goto out_nodestroy;
534 		}
535 	}
536 	spin_unlock(&rpc_credcache_lock);
537 	cred->cr_ops->crdestroy(cred);
538 	return;
539 out_nodestroy:
540 	spin_unlock(&rpc_credcache_lock);
541 }
542 EXPORT_SYMBOL_GPL(put_rpccred);
543 
544 __be32 *
rpcauth_marshcred(struct rpc_task * task,__be32 * p)545 rpcauth_marshcred(struct rpc_task *task, __be32 *p)
546 {
547 	struct rpc_cred	*cred = task->tk_rqstp->rq_cred;
548 
549 	dprintk("RPC: %5u marshaling %s cred %p\n",
550 		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
551 
552 	return cred->cr_ops->crmarshal(task, p);
553 }
554 
555 __be32 *
rpcauth_checkverf(struct rpc_task * task,__be32 * p)556 rpcauth_checkverf(struct rpc_task *task, __be32 *p)
557 {
558 	struct rpc_cred	*cred = task->tk_rqstp->rq_cred;
559 
560 	dprintk("RPC: %5u validating %s cred %p\n",
561 		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
562 
563 	return cred->cr_ops->crvalidate(task, p);
564 }
565 
rpcauth_wrap_req_encode(kxdreproc_t encode,struct rpc_rqst * rqstp,__be32 * data,void * obj)566 static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
567 				   __be32 *data, void *obj)
568 {
569 	struct xdr_stream xdr;
570 
571 	xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data);
572 	encode(rqstp, &xdr, obj);
573 }
574 
575 int
rpcauth_wrap_req(struct rpc_task * task,kxdreproc_t encode,void * rqstp,__be32 * data,void * obj)576 rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp,
577 		__be32 *data, void *obj)
578 {
579 	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
580 
581 	dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
582 			task->tk_pid, cred->cr_ops->cr_name, cred);
583 	if (cred->cr_ops->crwrap_req)
584 		return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
585 	/* By default, we encode the arguments normally. */
586 	rpcauth_wrap_req_encode(encode, rqstp, data, obj);
587 	return 0;
588 }
589 
590 static int
rpcauth_unwrap_req_decode(kxdrdproc_t decode,struct rpc_rqst * rqstp,__be32 * data,void * obj)591 rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
592 			  __be32 *data, void *obj)
593 {
594 	struct xdr_stream xdr;
595 
596 	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data);
597 	return decode(rqstp, &xdr, obj);
598 }
599 
600 int
rpcauth_unwrap_resp(struct rpc_task * task,kxdrdproc_t decode,void * rqstp,__be32 * data,void * obj)601 rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp,
602 		__be32 *data, void *obj)
603 {
604 	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
605 
606 	dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
607 			task->tk_pid, cred->cr_ops->cr_name, cred);
608 	if (cred->cr_ops->crunwrap_resp)
609 		return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
610 						   data, obj);
611 	/* By default, we decode the arguments normally. */
612 	return rpcauth_unwrap_req_decode(decode, rqstp, data, obj);
613 }
614 
615 int
rpcauth_refreshcred(struct rpc_task * task)616 rpcauth_refreshcred(struct rpc_task *task)
617 {
618 	struct rpc_cred	*cred;
619 	int err;
620 
621 	cred = task->tk_rqstp->rq_cred;
622 	if (cred == NULL) {
623 		err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags);
624 		if (err < 0)
625 			goto out;
626 		cred = task->tk_rqstp->rq_cred;
627 	};
628 	dprintk("RPC: %5u refreshing %s cred %p\n",
629 		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
630 
631 	err = cred->cr_ops->crrefresh(task);
632 out:
633 	if (err < 0)
634 		task->tk_status = err;
635 	return err;
636 }
637 
638 void
rpcauth_invalcred(struct rpc_task * task)639 rpcauth_invalcred(struct rpc_task *task)
640 {
641 	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
642 
643 	dprintk("RPC: %5u invalidating %s cred %p\n",
644 		task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
645 	if (cred)
646 		clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
647 }
648 
649 int
rpcauth_uptodatecred(struct rpc_task * task)650 rpcauth_uptodatecred(struct rpc_task *task)
651 {
652 	struct rpc_cred *cred = task->tk_rqstp->rq_cred;
653 
654 	return cred == NULL ||
655 		test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
656 }
657 
658 static struct shrinker rpc_cred_shrinker = {
659 	.shrink = rpcauth_cache_shrinker,
660 	.seeks = DEFAULT_SEEKS,
661 };
662 
rpcauth_init_module(void)663 int __init rpcauth_init_module(void)
664 {
665 	int err;
666 
667 	err = rpc_init_authunix();
668 	if (err < 0)
669 		goto out1;
670 	err = rpc_init_generic_auth();
671 	if (err < 0)
672 		goto out2;
673 	register_shrinker(&rpc_cred_shrinker);
674 	return 0;
675 out2:
676 	rpc_destroy_authunix();
677 out1:
678 	return err;
679 }
680 
rpcauth_remove_module(void)681 void rpcauth_remove_module(void)
682 {
683 	rpc_destroy_authunix();
684 	rpc_destroy_generic_auth();
685 	unregister_shrinker(&rpc_cred_shrinker);
686 }
687