blob: 9ac1b8c26c01184595f34de62db8ef23b15c6890 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/sunrpc/clnt.h>
15#include <linux/spinlock.h>
16
17#ifdef RPC_DEBUG
18# define RPCDBG_FACILITY RPCDBG_AUTH
19#endif
20
21static struct rpc_authops * auth_flavors[RPC_AUTH_MAXFLAVOR] = {
22 &authnull_ops, /* AUTH_NULL */
23 &authunix_ops, /* AUTH_UNIX */
24 NULL, /* others can be loadable modules */
25};
26
27static u32
28pseudoflavor_to_flavor(u32 flavor) {
29 if (flavor >= RPC_AUTH_MAXFLAVOR)
30 return RPC_AUTH_GSS;
31 return flavor;
32}
33
34int
35rpcauth_register(struct rpc_authops *ops)
36{
37 rpc_authflavor_t flavor;
38
39 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
40 return -EINVAL;
41 if (auth_flavors[flavor] != NULL)
42 return -EPERM; /* what else? */
43 auth_flavors[flavor] = ops;
44 return 0;
45}
46
47int
48rpcauth_unregister(struct rpc_authops *ops)
49{
50 rpc_authflavor_t flavor;
51
52 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
53 return -EINVAL;
54 if (auth_flavors[flavor] != ops)
55 return -EPERM; /* what else? */
56 auth_flavors[flavor] = NULL;
57 return 0;
58}
59
60struct rpc_auth *
61rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
62{
63 struct rpc_auth *auth;
64 struct rpc_authops *ops;
65 u32 flavor = pseudoflavor_to_flavor(pseudoflavor);
66
67 if (flavor >= RPC_AUTH_MAXFLAVOR || !(ops = auth_flavors[flavor]))
J. Bruce Fields6a192752005-06-22 17:16:23 +000068 return ERR_PTR(-EINVAL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 auth = ops->create(clnt, pseudoflavor);
J. Bruce Fields6a192752005-06-22 17:16:23 +000070 if (IS_ERR(auth))
71 return auth;
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 if (clnt->cl_auth)
73 rpcauth_destroy(clnt->cl_auth);
74 clnt->cl_auth = auth;
75 return auth;
76}
77
78void
79rpcauth_destroy(struct rpc_auth *auth)
80{
81 if (!atomic_dec_and_test(&auth->au_count))
82 return;
83 auth->au_ops->destroy(auth);
84}
85
86static DEFINE_SPINLOCK(rpc_credcache_lock);
87
88/*
89 * Initialize RPC credential cache
90 */
91int
92rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire)
93{
94 struct rpc_cred_cache *new;
95 int i;
96
Kris Katterjohn8b3a7002006-01-11 15:56:43 -080097 new = kmalloc(sizeof(*new), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 if (!new)
99 return -ENOMEM;
100 for (i = 0; i < RPC_CREDCACHE_NR; i++)
101 INIT_HLIST_HEAD(&new->hashtable[i]);
102 new->expire = expire;
103 new->nextgc = jiffies + (expire >> 1);
104 auth->au_credcache = new;
105 return 0;
106}
107
108/*
109 * Destroy a list of credentials
110 */
111static inline
112void rpcauth_destroy_credlist(struct hlist_head *head)
113{
114 struct rpc_cred *cred;
115
116 while (!hlist_empty(head)) {
117 cred = hlist_entry(head->first, struct rpc_cred, cr_hash);
118 hlist_del_init(&cred->cr_hash);
119 put_rpccred(cred);
120 }
121}
122
123/*
124 * Clear the RPC credential cache, and delete those credentials
125 * that are not referenced.
126 */
127void
128rpcauth_free_credcache(struct rpc_auth *auth)
129{
130 struct rpc_cred_cache *cache = auth->au_credcache;
131 HLIST_HEAD(free);
132 struct hlist_node *pos, *next;
133 struct rpc_cred *cred;
134 int i;
135
136 spin_lock(&rpc_credcache_lock);
137 for (i = 0; i < RPC_CREDCACHE_NR; i++) {
138 hlist_for_each_safe(pos, next, &cache->hashtable[i]) {
139 cred = hlist_entry(pos, struct rpc_cred, cr_hash);
140 __hlist_del(&cred->cr_hash);
141 hlist_add_head(&cred->cr_hash, &free);
142 }
143 }
144 spin_unlock(&rpc_credcache_lock);
145 rpcauth_destroy_credlist(&free);
146}
147
148static void
149rpcauth_prune_expired(struct rpc_auth *auth, struct rpc_cred *cred, struct hlist_head *free)
150{
151 if (atomic_read(&cred->cr_count) != 1)
152 return;
153 if (time_after(jiffies, cred->cr_expire + auth->au_credcache->expire))
154 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
155 if (!(cred->cr_flags & RPCAUTH_CRED_UPTODATE)) {
156 __hlist_del(&cred->cr_hash);
157 hlist_add_head(&cred->cr_hash, free);
158 }
159}
160
161/*
162 * Remove stale credentials. Avoid sleeping inside the loop.
163 */
164static void
165rpcauth_gc_credcache(struct rpc_auth *auth, struct hlist_head *free)
166{
167 struct rpc_cred_cache *cache = auth->au_credcache;
168 struct hlist_node *pos, *next;
169 struct rpc_cred *cred;
170 int i;
171
172 dprintk("RPC: gc'ing RPC credentials for auth %p\n", auth);
173 for (i = 0; i < RPC_CREDCACHE_NR; i++) {
174 hlist_for_each_safe(pos, next, &cache->hashtable[i]) {
175 cred = hlist_entry(pos, struct rpc_cred, cr_hash);
176 rpcauth_prune_expired(auth, cred, free);
177 }
178 }
179 cache->nextgc = jiffies + cache->expire;
180}
181
182/*
183 * Look up a process' credentials in the authentication cache
184 */
185struct rpc_cred *
186rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
187 int taskflags)
188{
189 struct rpc_cred_cache *cache = auth->au_credcache;
190 HLIST_HEAD(free);
191 struct hlist_node *pos, *next;
192 struct rpc_cred *new = NULL,
193 *cred = NULL;
194 int nr = 0;
195
196 if (!(taskflags & RPC_TASK_ROOTCREDS))
197 nr = acred->uid & RPC_CREDCACHE_MASK;
198retry:
199 spin_lock(&rpc_credcache_lock);
200 if (time_before(cache->nextgc, jiffies))
201 rpcauth_gc_credcache(auth, &free);
202 hlist_for_each_safe(pos, next, &cache->hashtable[nr]) {
203 struct rpc_cred *entry;
204 entry = hlist_entry(pos, struct rpc_cred, cr_hash);
205 if (entry->cr_ops->crmatch(acred, entry, taskflags)) {
206 hlist_del(&entry->cr_hash);
207 cred = entry;
208 break;
209 }
210 rpcauth_prune_expired(auth, entry, &free);
211 }
212 if (new) {
213 if (cred)
214 hlist_add_head(&new->cr_hash, &free);
215 else
216 cred = new;
217 }
218 if (cred) {
219 hlist_add_head(&cred->cr_hash, &cache->hashtable[nr]);
220 get_rpccred(cred);
221 }
222 spin_unlock(&rpc_credcache_lock);
223
224 rpcauth_destroy_credlist(&free);
225
226 if (!cred) {
227 new = auth->au_ops->crcreate(auth, acred, taskflags);
228 if (!IS_ERR(new)) {
229#ifdef RPC_DEBUG
230 new->cr_magic = RPCAUTH_CRED_MAGIC;
231#endif
232 goto retry;
233 } else
234 cred = new;
235 }
236
237 return (struct rpc_cred *) cred;
238}
239
240struct rpc_cred *
241rpcauth_lookupcred(struct rpc_auth *auth, int taskflags)
242{
243 struct auth_cred acred = {
244 .uid = current->fsuid,
245 .gid = current->fsgid,
246 .group_info = current->group_info,
247 };
248 struct rpc_cred *ret;
249
250 dprintk("RPC: looking up %s cred\n",
251 auth->au_ops->au_name);
252 get_group_info(acred.group_info);
253 ret = auth->au_ops->lookup_cred(auth, &acred, taskflags);
254 put_group_info(acred.group_info);
255 return ret;
256}
257
258struct rpc_cred *
259rpcauth_bindcred(struct rpc_task *task)
260{
261 struct rpc_auth *auth = task->tk_auth;
262 struct auth_cred acred = {
263 .uid = current->fsuid,
264 .gid = current->fsgid,
265 .group_info = current->group_info,
266 };
267 struct rpc_cred *ret;
268
269 dprintk("RPC: %4d looking up %s cred\n",
270 task->tk_pid, task->tk_auth->au_ops->au_name);
271 get_group_info(acred.group_info);
272 ret = auth->au_ops->lookup_cred(auth, &acred, task->tk_flags);
273 if (!IS_ERR(ret))
274 task->tk_msg.rpc_cred = ret;
275 else
276 task->tk_status = PTR_ERR(ret);
277 put_group_info(acred.group_info);
278 return ret;
279}
280
281void
282rpcauth_holdcred(struct rpc_task *task)
283{
284 dprintk("RPC: %4d holding %s cred %p\n",
285 task->tk_pid, task->tk_auth->au_ops->au_name, task->tk_msg.rpc_cred);
286 if (task->tk_msg.rpc_cred)
287 get_rpccred(task->tk_msg.rpc_cred);
288}
289
290void
291put_rpccred(struct rpc_cred *cred)
292{
293 cred->cr_expire = jiffies;
294 if (!atomic_dec_and_test(&cred->cr_count))
295 return;
296 cred->cr_ops->crdestroy(cred);
297}
298
299void
300rpcauth_unbindcred(struct rpc_task *task)
301{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 struct rpc_cred *cred = task->tk_msg.rpc_cred;
303
304 dprintk("RPC: %4d releasing %s cred %p\n",
Chuck Lever0bbacc42005-11-01 16:53:32 -0500305 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306
307 put_rpccred(cred);
308 task->tk_msg.rpc_cred = NULL;
309}
310
311u32 *
312rpcauth_marshcred(struct rpc_task *task, u32 *p)
313{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 struct rpc_cred *cred = task->tk_msg.rpc_cred;
315
316 dprintk("RPC: %4d marshaling %s cred %p\n",
Chuck Lever0bbacc42005-11-01 16:53:32 -0500317 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
318
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 return cred->cr_ops->crmarshal(task, p);
320}
321
322u32 *
323rpcauth_checkverf(struct rpc_task *task, u32 *p)
324{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 struct rpc_cred *cred = task->tk_msg.rpc_cred;
326
327 dprintk("RPC: %4d validating %s cred %p\n",
Chuck Lever0bbacc42005-11-01 16:53:32 -0500328 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
329
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 return cred->cr_ops->crvalidate(task, p);
331}
332
333int
334rpcauth_wrap_req(struct rpc_task *task, kxdrproc_t encode, void *rqstp,
335 u32 *data, void *obj)
336{
337 struct rpc_cred *cred = task->tk_msg.rpc_cred;
338
339 dprintk("RPC: %4d using %s cred %p to wrap rpc data\n",
340 task->tk_pid, cred->cr_ops->cr_name, cred);
341 if (cred->cr_ops->crwrap_req)
342 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
343 /* By default, we encode the arguments normally. */
344 return encode(rqstp, data, obj);
345}
346
347int
348rpcauth_unwrap_resp(struct rpc_task *task, kxdrproc_t decode, void *rqstp,
349 u32 *data, void *obj)
350{
351 struct rpc_cred *cred = task->tk_msg.rpc_cred;
352
353 dprintk("RPC: %4d using %s cred %p to unwrap rpc data\n",
354 task->tk_pid, cred->cr_ops->cr_name, cred);
355 if (cred->cr_ops->crunwrap_resp)
356 return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
357 data, obj);
358 /* By default, we decode the arguments normally. */
359 return decode(rqstp, data, obj);
360}
361
362int
363rpcauth_refreshcred(struct rpc_task *task)
364{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 struct rpc_cred *cred = task->tk_msg.rpc_cred;
366 int err;
367
368 dprintk("RPC: %4d refreshing %s cred %p\n",
Chuck Lever0bbacc42005-11-01 16:53:32 -0500369 task->tk_pid, task->tk_auth->au_ops->au_name, cred);
370
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 err = cred->cr_ops->crrefresh(task);
372 if (err < 0)
373 task->tk_status = err;
374 return err;
375}
376
377void
378rpcauth_invalcred(struct rpc_task *task)
379{
380 dprintk("RPC: %4d invalidating %s cred %p\n",
381 task->tk_pid, task->tk_auth->au_ops->au_name, task->tk_msg.rpc_cred);
382 spin_lock(&rpc_credcache_lock);
383 if (task->tk_msg.rpc_cred)
384 task->tk_msg.rpc_cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
385 spin_unlock(&rpc_credcache_lock);
386}
387
388int
389rpcauth_uptodatecred(struct rpc_task *task)
390{
391 return !(task->tk_msg.rpc_cred) ||
392 (task->tk_msg.rpc_cred->cr_flags & RPCAUTH_CRED_UPTODATE);
393}