2 * linux/net/sunrpc/auth.c
4 * Generic RPC client authentication API.
6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
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/sunrpc/clnt.h>
15 #include <linux/spinlock.h>
18 # define RPCDBG_FACILITY RPCDBG_AUTH
21 static DEFINE_SPINLOCK(rpc_authflavor_lock);
22 static const struct rpc_authops *auth_flavors[RPC_AUTH_MAXFLAVOR] = {
23 &authnull_ops, /* AUTH_NULL */
24 &authunix_ops, /* AUTH_UNIX */
25 NULL, /* others can be loadable modules */
28 static LIST_HEAD(cred_unused);
31 pseudoflavor_to_flavor(u32 flavor) {
32 if (flavor >= RPC_AUTH_MAXFLAVOR)
38 rpcauth_register(const struct rpc_authops *ops)
40 rpc_authflavor_t flavor;
43 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
45 spin_lock(&rpc_authflavor_lock);
46 if (auth_flavors[flavor] == NULL) {
47 auth_flavors[flavor] = ops;
50 spin_unlock(&rpc_authflavor_lock);
55 rpcauth_unregister(const struct rpc_authops *ops)
57 rpc_authflavor_t flavor;
60 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
62 spin_lock(&rpc_authflavor_lock);
63 if (auth_flavors[flavor] == ops) {
64 auth_flavors[flavor] = NULL;
67 spin_unlock(&rpc_authflavor_lock);
72 rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
74 struct rpc_auth *auth;
75 const struct rpc_authops *ops;
76 u32 flavor = pseudoflavor_to_flavor(pseudoflavor);
78 auth = ERR_PTR(-EINVAL);
79 if (flavor >= RPC_AUTH_MAXFLAVOR)
83 if ((ops = auth_flavors[flavor]) == NULL)
84 request_module("rpc-auth-%u", flavor);
86 spin_lock(&rpc_authflavor_lock);
87 ops = auth_flavors[flavor];
88 if (ops == NULL || !try_module_get(ops->owner)) {
89 spin_unlock(&rpc_authflavor_lock);
92 spin_unlock(&rpc_authflavor_lock);
93 auth = ops->create(clnt, pseudoflavor);
94 module_put(ops->owner);
98 rpcauth_release(clnt->cl_auth);
106 rpcauth_release(struct rpc_auth *auth)
108 if (!atomic_dec_and_test(&auth->au_count))
110 auth->au_ops->destroy(auth);
113 static DEFINE_SPINLOCK(rpc_credcache_lock);
116 rpcauth_unhash_cred_locked(struct rpc_cred *cred)
118 hlist_del_rcu(&cred->cr_hash);
119 smp_mb__before_clear_bit();
120 clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
124 * Initialize RPC credential cache
127 rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire)
129 struct rpc_cred_cache *new;
132 new = kmalloc(sizeof(*new), GFP_KERNEL);
135 for (i = 0; i < RPC_CREDCACHE_NR; i++)
136 INIT_HLIST_HEAD(&new->hashtable[i]);
137 new->expire = expire;
138 new->nextgc = jiffies + (expire >> 1);
139 auth->au_credcache = new;
144 * Destroy a list of credentials
147 void rpcauth_destroy_credlist(struct list_head *head)
149 struct rpc_cred *cred;
151 while (!list_empty(head)) {
152 cred = list_entry(head->next, struct rpc_cred, cr_lru);
153 list_del_init(&cred->cr_lru);
159 * Clear the RPC credential cache, and delete those credentials
160 * that are not referenced.
163 rpcauth_clear_credcache(struct rpc_cred_cache *cache)
166 struct hlist_head *head;
167 struct rpc_cred *cred;
170 spin_lock(&rpc_credcache_lock);
171 for (i = 0; i < RPC_CREDCACHE_NR; i++) {
172 head = &cache->hashtable[i];
173 while (!hlist_empty(head)) {
174 cred = hlist_entry(head->first, struct rpc_cred, cr_hash);
176 list_move_tail(&cred->cr_lru, &free);
177 rpcauth_unhash_cred_locked(cred);
180 spin_unlock(&rpc_credcache_lock);
181 rpcauth_destroy_credlist(&free);
185 * Destroy the RPC credential cache
188 rpcauth_destroy_credcache(struct rpc_auth *auth)
190 struct rpc_cred_cache *cache = auth->au_credcache;
193 auth->au_credcache = NULL;
194 rpcauth_clear_credcache(cache);
200 * Remove stale credentials. Avoid sleeping inside the loop.
203 rpcauth_prune_expired(struct list_head *free)
205 struct rpc_cred *cred;
207 while (!list_empty(&cred_unused)) {
208 cred = list_entry(cred_unused.next, struct rpc_cred, cr_lru);
209 if (time_after(jiffies, cred->cr_expire +
210 cred->cr_auth->au_credcache->expire))
212 list_del_init(&cred->cr_lru);
213 if (atomic_read(&cred->cr_count) != 0)
216 list_add_tail(&cred->cr_lru, free);
217 rpcauth_unhash_cred_locked(cred);
222 * Run garbage collector.
225 rpcauth_gc_credcache(struct rpc_cred_cache *cache, struct list_head *free)
227 if (list_empty(&cred_unused) || time_before(jiffies, cache->nextgc))
229 spin_lock(&rpc_credcache_lock);
230 cache->nextgc = jiffies + cache->expire;
231 rpcauth_prune_expired(free);
232 spin_unlock(&rpc_credcache_lock);
236 * Look up a process' credentials in the authentication cache
239 rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
243 struct rpc_cred_cache *cache = auth->au_credcache;
244 struct hlist_node *pos;
245 struct rpc_cred *cred = NULL,
249 if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS))
250 nr = acred->uid & RPC_CREDCACHE_MASK;
253 hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) {
254 if (!entry->cr_ops->crmatch(acred, entry, flags))
256 spin_lock(&rpc_credcache_lock);
257 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
258 spin_unlock(&rpc_credcache_lock);
261 cred = get_rpccred(entry);
262 spin_unlock(&rpc_credcache_lock);
268 rpcauth_gc_credcache(cache, &free);
272 new = auth->au_ops->crcreate(auth, acred, flags);
278 spin_lock(&rpc_credcache_lock);
279 hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) {
280 if (!entry->cr_ops->crmatch(acred, entry, flags))
282 cred = get_rpccred(entry);
287 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
288 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
290 list_add_tail(&new->cr_lru, &free);
291 rpcauth_prune_expired(&free);
292 cache->nextgc = jiffies + cache->expire;
293 spin_unlock(&rpc_credcache_lock);
295 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)
296 && cred->cr_ops->cr_init != NULL
297 && !(flags & RPCAUTH_LOOKUP_NEW)) {
298 int res = cred->cr_ops->cr_init(auth, cred);
304 rpcauth_destroy_credlist(&free);
310 rpcauth_lookupcred(struct rpc_auth *auth, int flags)
312 struct auth_cred acred = {
313 .uid = current->fsuid,
314 .gid = current->fsgid,
315 .group_info = current->group_info,
317 struct rpc_cred *ret;
319 dprintk("RPC: looking up %s cred\n",
320 auth->au_ops->au_name);
321 get_group_info(acred.group_info);
322 ret = auth->au_ops->lookup_cred(auth, &acred, flags);
323 put_group_info(acred.group_info);
328 rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
329 struct rpc_auth *auth, const struct rpc_credops *ops)
331 INIT_HLIST_NODE(&cred->cr_hash);
332 INIT_LIST_HEAD(&cred->cr_lru);
333 atomic_set(&cred->cr_count, 1);
334 cred->cr_auth = auth;
336 cred->cr_expire = jiffies;
338 cred->cr_magic = RPCAUTH_CRED_MAGIC;
340 cred->cr_uid = acred->uid;
342 EXPORT_SYMBOL(rpcauth_init_cred);
345 rpcauth_bindcred(struct rpc_task *task)
347 struct rpc_auth *auth = task->tk_auth;
348 struct auth_cred acred = {
349 .uid = current->fsuid,
350 .gid = current->fsgid,
351 .group_info = current->group_info,
353 struct rpc_cred *ret;
356 dprintk("RPC: %5u looking up %s cred\n",
357 task->tk_pid, task->tk_auth->au_ops->au_name);
358 get_group_info(acred.group_info);
359 if (task->tk_flags & RPC_TASK_ROOTCREDS)
360 flags |= RPCAUTH_LOOKUP_ROOTCREDS;
361 ret = auth->au_ops->lookup_cred(auth, &acred, flags);
363 task->tk_msg.rpc_cred = ret;
365 task->tk_status = PTR_ERR(ret);
366 put_group_info(acred.group_info);
371 rpcauth_holdcred(struct rpc_task *task)
373 dprintk("RPC: %5u holding %s cred %p\n",
374 task->tk_pid, task->tk_auth->au_ops->au_name,
375 task->tk_msg.rpc_cred);
376 if (task->tk_msg.rpc_cred)
377 get_rpccred(task->tk_msg.rpc_cred);
381 put_rpccred(struct rpc_cred *cred)
383 /* Fast path for unhashed credentials */
384 if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0)
387 if (!atomic_dec_and_test(&cred->cr_count))
391 if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
393 if (!list_empty(&cred->cr_lru))
394 list_del_init(&cred->cr_lru);
395 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0)
396 rpcauth_unhash_cred_locked(cred);
397 else if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
398 cred->cr_expire = jiffies;
399 list_add_tail(&cred->cr_lru, &cred_unused);
400 spin_unlock(&rpc_credcache_lock);
403 spin_unlock(&rpc_credcache_lock);
405 cred->cr_ops->crdestroy(cred);
409 rpcauth_unbindcred(struct rpc_task *task)
411 struct rpc_cred *cred = task->tk_msg.rpc_cred;
413 dprintk("RPC: %5u releasing %s cred %p\n",
414 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
417 task->tk_msg.rpc_cred = NULL;
421 rpcauth_marshcred(struct rpc_task *task, __be32 *p)
423 struct rpc_cred *cred = task->tk_msg.rpc_cred;
425 dprintk("RPC: %5u marshaling %s cred %p\n",
426 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
428 return cred->cr_ops->crmarshal(task, p);
432 rpcauth_checkverf(struct rpc_task *task, __be32 *p)
434 struct rpc_cred *cred = task->tk_msg.rpc_cred;
436 dprintk("RPC: %5u validating %s cred %p\n",
437 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
439 return cred->cr_ops->crvalidate(task, p);
443 rpcauth_wrap_req(struct rpc_task *task, kxdrproc_t encode, void *rqstp,
444 __be32 *data, void *obj)
446 struct rpc_cred *cred = task->tk_msg.rpc_cred;
448 dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
449 task->tk_pid, cred->cr_ops->cr_name, cred);
450 if (cred->cr_ops->crwrap_req)
451 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
452 /* By default, we encode the arguments normally. */
453 return encode(rqstp, data, obj);
457 rpcauth_unwrap_resp(struct rpc_task *task, kxdrproc_t decode, void *rqstp,
458 __be32 *data, void *obj)
460 struct rpc_cred *cred = task->tk_msg.rpc_cred;
462 dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
463 task->tk_pid, cred->cr_ops->cr_name, cred);
464 if (cred->cr_ops->crunwrap_resp)
465 return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
467 /* By default, we decode the arguments normally. */
468 return decode(rqstp, data, obj);
472 rpcauth_refreshcred(struct rpc_task *task)
474 struct rpc_cred *cred = task->tk_msg.rpc_cred;
477 dprintk("RPC: %5u refreshing %s cred %p\n",
478 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
480 err = cred->cr_ops->crrefresh(task);
482 task->tk_status = err;
487 rpcauth_invalcred(struct rpc_task *task)
489 struct rpc_cred *cred = task->tk_msg.rpc_cred;
491 dprintk("RPC: %5u invalidating %s cred %p\n",
492 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
494 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
498 rpcauth_uptodatecred(struct rpc_task *task)
500 struct rpc_cred *cred = task->tk_msg.rpc_cred;
502 return cred == NULL ||
503 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;