1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * linux/net/sunrpc/auth.c |
4 | * |
5 | * Generic RPC client authentication API. |
6 | * |
7 | * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> |
8 | */ |
9 | |
10 | #include <linux/types.h> |
11 | #include <linux/sched.h> |
12 | #include <linux/cred.h> |
13 | #include <linux/module.h> |
14 | #include <linux/slab.h> |
15 | #include <linux/errno.h> |
16 | #include <linux/hash.h> |
17 | #include <linux/sunrpc/clnt.h> |
18 | #include <linux/sunrpc/gss_api.h> |
19 | #include <linux/spinlock.h> |
20 | |
21 | #include <trace/events/sunrpc.h> |
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 const struct rpc_authops __rcu *auth_flavors[RPC_AUTH_MAXFLAVOR] = { |
33 | [RPC_AUTH_NULL] = (const struct rpc_authops __force __rcu *)&authnull_ops, |
34 | [RPC_AUTH_UNIX] = (const struct rpc_authops __force __rcu *)&authunix_ops, |
35 | [RPC_AUTH_TLS] = (const struct rpc_authops __force __rcu *)&authtls_ops, |
36 | }; |
37 | |
38 | static LIST_HEAD(cred_unused); |
39 | static unsigned long number_cred_unused; |
40 | |
41 | static struct cred machine_cred = { |
42 | .usage = ATOMIC_INIT(1), |
43 | #ifdef CONFIG_DEBUG_CREDENTIALS |
44 | .magic = CRED_MAGIC, |
45 | #endif |
46 | }; |
47 | |
48 | /* |
49 | * Return the machine_cred pointer to be used whenever |
50 | * the a generic machine credential is needed. |
51 | */ |
52 | const struct cred *rpc_machine_cred(void) |
53 | { |
54 | return &machine_cred; |
55 | } |
56 | EXPORT_SYMBOL_GPL(rpc_machine_cred); |
57 | |
58 | #define MAX_HASHTABLE_BITS (14) |
59 | static int param_set_hashtbl_sz(const char *val, const struct kernel_param *kp) |
60 | { |
61 | unsigned long num; |
62 | unsigned int nbits; |
63 | int ret; |
64 | |
65 | if (!val) |
66 | goto out_inval; |
67 | ret = kstrtoul(s: val, base: 0, res: &num); |
68 | if (ret) |
69 | goto out_inval; |
70 | nbits = fls(x: num - 1); |
71 | if (nbits > MAX_HASHTABLE_BITS || nbits < 2) |
72 | goto out_inval; |
73 | *(unsigned int *)kp->arg = nbits; |
74 | return 0; |
75 | out_inval: |
76 | return -EINVAL; |
77 | } |
78 | |
79 | static int param_get_hashtbl_sz(char *buffer, const struct kernel_param *kp) |
80 | { |
81 | unsigned int nbits; |
82 | |
83 | nbits = *(unsigned int *)kp->arg; |
84 | return sprintf(buf: buffer, fmt: "%u\n" , 1U << nbits); |
85 | } |
86 | |
87 | #define param_check_hashtbl_sz(name, p) __param_check(name, p, unsigned int); |
88 | |
89 | static const struct kernel_param_ops param_ops_hashtbl_sz = { |
90 | .set = param_set_hashtbl_sz, |
91 | .get = param_get_hashtbl_sz, |
92 | }; |
93 | |
94 | module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644); |
95 | MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size" ); |
96 | |
97 | static unsigned long auth_max_cred_cachesize = ULONG_MAX; |
98 | module_param(auth_max_cred_cachesize, ulong, 0644); |
99 | MODULE_PARM_DESC(auth_max_cred_cachesize, "RPC credential maximum total cache size" ); |
100 | |
101 | static u32 |
102 | pseudoflavor_to_flavor(u32 flavor) { |
103 | if (flavor > RPC_AUTH_MAXFLAVOR) |
104 | return RPC_AUTH_GSS; |
105 | return flavor; |
106 | } |
107 | |
108 | int |
109 | rpcauth_register(const struct rpc_authops *ops) |
110 | { |
111 | const struct rpc_authops *old; |
112 | rpc_authflavor_t flavor; |
113 | |
114 | if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR) |
115 | return -EINVAL; |
116 | old = cmpxchg((const struct rpc_authops ** __force)&auth_flavors[flavor], NULL, ops); |
117 | if (old == NULL || old == ops) |
118 | return 0; |
119 | return -EPERM; |
120 | } |
121 | EXPORT_SYMBOL_GPL(rpcauth_register); |
122 | |
123 | int |
124 | rpcauth_unregister(const struct rpc_authops *ops) |
125 | { |
126 | const struct rpc_authops *old; |
127 | rpc_authflavor_t flavor; |
128 | |
129 | if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR) |
130 | return -EINVAL; |
131 | |
132 | old = cmpxchg((const struct rpc_authops ** __force)&auth_flavors[flavor], ops, NULL); |
133 | if (old == ops || old == NULL) |
134 | return 0; |
135 | return -EPERM; |
136 | } |
137 | EXPORT_SYMBOL_GPL(rpcauth_unregister); |
138 | |
139 | static const struct rpc_authops * |
140 | rpcauth_get_authops(rpc_authflavor_t flavor) |
141 | { |
142 | const struct rpc_authops *ops; |
143 | |
144 | if (flavor >= RPC_AUTH_MAXFLAVOR) |
145 | return NULL; |
146 | |
147 | rcu_read_lock(); |
148 | ops = rcu_dereference(auth_flavors[flavor]); |
149 | if (ops == NULL) { |
150 | rcu_read_unlock(); |
151 | request_module("rpc-auth-%u" , flavor); |
152 | rcu_read_lock(); |
153 | ops = rcu_dereference(auth_flavors[flavor]); |
154 | if (ops == NULL) |
155 | goto out; |
156 | } |
157 | if (!try_module_get(module: ops->owner)) |
158 | ops = NULL; |
159 | out: |
160 | rcu_read_unlock(); |
161 | return ops; |
162 | } |
163 | |
164 | static void |
165 | rpcauth_put_authops(const struct rpc_authops *ops) |
166 | { |
167 | module_put(module: ops->owner); |
168 | } |
169 | |
170 | /** |
171 | * rpcauth_get_pseudoflavor - check if security flavor is supported |
172 | * @flavor: a security flavor |
173 | * @info: a GSS mech OID, quality of protection, and service value |
174 | * |
175 | * Verifies that an appropriate kernel module is available or already loaded. |
176 | * Returns an equivalent pseudoflavor, or RPC_AUTH_MAXFLAVOR if "flavor" is |
177 | * not supported locally. |
178 | */ |
179 | rpc_authflavor_t |
180 | rpcauth_get_pseudoflavor(rpc_authflavor_t flavor, struct rpcsec_gss_info *info) |
181 | { |
182 | const struct rpc_authops *ops = rpcauth_get_authops(flavor); |
183 | rpc_authflavor_t pseudoflavor; |
184 | |
185 | if (!ops) |
186 | return RPC_AUTH_MAXFLAVOR; |
187 | pseudoflavor = flavor; |
188 | if (ops->info2flavor != NULL) |
189 | pseudoflavor = ops->info2flavor(info); |
190 | |
191 | rpcauth_put_authops(ops); |
192 | return pseudoflavor; |
193 | } |
194 | EXPORT_SYMBOL_GPL(rpcauth_get_pseudoflavor); |
195 | |
196 | /** |
197 | * rpcauth_get_gssinfo - find GSS tuple matching a GSS pseudoflavor |
198 | * @pseudoflavor: GSS pseudoflavor to match |
199 | * @info: rpcsec_gss_info structure to fill in |
200 | * |
201 | * Returns zero and fills in "info" if pseudoflavor matches a |
202 | * supported mechanism. |
203 | */ |
204 | int |
205 | rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info) |
206 | { |
207 | rpc_authflavor_t flavor = pseudoflavor_to_flavor(flavor: pseudoflavor); |
208 | const struct rpc_authops *ops; |
209 | int result; |
210 | |
211 | ops = rpcauth_get_authops(flavor); |
212 | if (ops == NULL) |
213 | return -ENOENT; |
214 | |
215 | result = -ENOENT; |
216 | if (ops->flavor2info != NULL) |
217 | result = ops->flavor2info(pseudoflavor, info); |
218 | |
219 | rpcauth_put_authops(ops); |
220 | return result; |
221 | } |
222 | EXPORT_SYMBOL_GPL(rpcauth_get_gssinfo); |
223 | |
224 | struct rpc_auth * |
225 | rpcauth_create(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt) |
226 | { |
227 | struct rpc_auth *auth = ERR_PTR(error: -EINVAL); |
228 | const struct rpc_authops *ops; |
229 | u32 flavor = pseudoflavor_to_flavor(flavor: args->pseudoflavor); |
230 | |
231 | ops = rpcauth_get_authops(flavor); |
232 | if (ops == NULL) |
233 | goto out; |
234 | |
235 | auth = ops->create(args, clnt); |
236 | |
237 | rpcauth_put_authops(ops); |
238 | if (IS_ERR(ptr: auth)) |
239 | return auth; |
240 | if (clnt->cl_auth) |
241 | rpcauth_release(clnt->cl_auth); |
242 | clnt->cl_auth = auth; |
243 | |
244 | out: |
245 | return auth; |
246 | } |
247 | EXPORT_SYMBOL_GPL(rpcauth_create); |
248 | |
249 | void |
250 | rpcauth_release(struct rpc_auth *auth) |
251 | { |
252 | if (!refcount_dec_and_test(r: &auth->au_count)) |
253 | return; |
254 | auth->au_ops->destroy(auth); |
255 | } |
256 | |
257 | static DEFINE_SPINLOCK(rpc_credcache_lock); |
258 | |
259 | /* |
260 | * On success, the caller is responsible for freeing the reference |
261 | * held by the hashtable |
262 | */ |
263 | static bool |
264 | rpcauth_unhash_cred_locked(struct rpc_cred *cred) |
265 | { |
266 | if (!test_and_clear_bit(RPCAUTH_CRED_HASHED, addr: &cred->cr_flags)) |
267 | return false; |
268 | hlist_del_rcu(n: &cred->cr_hash); |
269 | return true; |
270 | } |
271 | |
272 | static bool |
273 | rpcauth_unhash_cred(struct rpc_cred *cred) |
274 | { |
275 | spinlock_t *cache_lock; |
276 | bool ret; |
277 | |
278 | if (!test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags)) |
279 | return false; |
280 | cache_lock = &cred->cr_auth->au_credcache->lock; |
281 | spin_lock(lock: cache_lock); |
282 | ret = rpcauth_unhash_cred_locked(cred); |
283 | spin_unlock(lock: cache_lock); |
284 | return ret; |
285 | } |
286 | |
287 | /* |
288 | * Initialize RPC credential cache |
289 | */ |
290 | int |
291 | rpcauth_init_credcache(struct rpc_auth *auth) |
292 | { |
293 | struct rpc_cred_cache *new; |
294 | unsigned int hashsize; |
295 | |
296 | new = kmalloc(size: sizeof(*new), GFP_KERNEL); |
297 | if (!new) |
298 | goto out_nocache; |
299 | new->hashbits = auth_hashbits; |
300 | hashsize = 1U << new->hashbits; |
301 | new->hashtable = kcalloc(n: hashsize, size: sizeof(new->hashtable[0]), GFP_KERNEL); |
302 | if (!new->hashtable) |
303 | goto out_nohashtbl; |
304 | spin_lock_init(&new->lock); |
305 | auth->au_credcache = new; |
306 | return 0; |
307 | out_nohashtbl: |
308 | kfree(objp: new); |
309 | out_nocache: |
310 | return -ENOMEM; |
311 | } |
312 | EXPORT_SYMBOL_GPL(rpcauth_init_credcache); |
313 | |
314 | char * |
315 | rpcauth_stringify_acceptor(struct rpc_cred *cred) |
316 | { |
317 | if (!cred->cr_ops->crstringify_acceptor) |
318 | return NULL; |
319 | return cred->cr_ops->crstringify_acceptor(cred); |
320 | } |
321 | EXPORT_SYMBOL_GPL(rpcauth_stringify_acceptor); |
322 | |
323 | /* |
324 | * Destroy a list of credentials |
325 | */ |
326 | static inline |
327 | void rpcauth_destroy_credlist(struct list_head *head) |
328 | { |
329 | struct rpc_cred *cred; |
330 | |
331 | while (!list_empty(head)) { |
332 | cred = list_entry(head->next, struct rpc_cred, cr_lru); |
333 | list_del_init(entry: &cred->cr_lru); |
334 | put_rpccred(cred); |
335 | } |
336 | } |
337 | |
338 | static void |
339 | rpcauth_lru_add_locked(struct rpc_cred *cred) |
340 | { |
341 | if (!list_empty(head: &cred->cr_lru)) |
342 | return; |
343 | number_cred_unused++; |
344 | list_add_tail(new: &cred->cr_lru, head: &cred_unused); |
345 | } |
346 | |
347 | static void |
348 | rpcauth_lru_add(struct rpc_cred *cred) |
349 | { |
350 | if (!list_empty(head: &cred->cr_lru)) |
351 | return; |
352 | spin_lock(lock: &rpc_credcache_lock); |
353 | rpcauth_lru_add_locked(cred); |
354 | spin_unlock(lock: &rpc_credcache_lock); |
355 | } |
356 | |
357 | static void |
358 | rpcauth_lru_remove_locked(struct rpc_cred *cred) |
359 | { |
360 | if (list_empty(head: &cred->cr_lru)) |
361 | return; |
362 | number_cred_unused--; |
363 | list_del_init(entry: &cred->cr_lru); |
364 | } |
365 | |
366 | static void |
367 | rpcauth_lru_remove(struct rpc_cred *cred) |
368 | { |
369 | if (list_empty(head: &cred->cr_lru)) |
370 | return; |
371 | spin_lock(lock: &rpc_credcache_lock); |
372 | rpcauth_lru_remove_locked(cred); |
373 | spin_unlock(lock: &rpc_credcache_lock); |
374 | } |
375 | |
376 | /* |
377 | * Clear the RPC credential cache, and delete those credentials |
378 | * that are not referenced. |
379 | */ |
380 | void |
381 | rpcauth_clear_credcache(struct rpc_cred_cache *cache) |
382 | { |
383 | LIST_HEAD(free); |
384 | struct hlist_head *head; |
385 | struct rpc_cred *cred; |
386 | unsigned int hashsize = 1U << cache->hashbits; |
387 | int i; |
388 | |
389 | spin_lock(lock: &rpc_credcache_lock); |
390 | spin_lock(lock: &cache->lock); |
391 | for (i = 0; i < hashsize; i++) { |
392 | head = &cache->hashtable[i]; |
393 | while (!hlist_empty(h: head)) { |
394 | cred = hlist_entry(head->first, struct rpc_cred, cr_hash); |
395 | rpcauth_unhash_cred_locked(cred); |
396 | /* Note: We now hold a reference to cred */ |
397 | rpcauth_lru_remove_locked(cred); |
398 | list_add_tail(new: &cred->cr_lru, head: &free); |
399 | } |
400 | } |
401 | spin_unlock(lock: &cache->lock); |
402 | spin_unlock(lock: &rpc_credcache_lock); |
403 | rpcauth_destroy_credlist(head: &free); |
404 | } |
405 | |
406 | /* |
407 | * Destroy the RPC credential cache |
408 | */ |
409 | void |
410 | rpcauth_destroy_credcache(struct rpc_auth *auth) |
411 | { |
412 | struct rpc_cred_cache *cache = auth->au_credcache; |
413 | |
414 | if (cache) { |
415 | auth->au_credcache = NULL; |
416 | rpcauth_clear_credcache(cache); |
417 | kfree(objp: cache->hashtable); |
418 | kfree(objp: cache); |
419 | } |
420 | } |
421 | EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache); |
422 | |
423 | |
424 | #define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ) |
425 | |
426 | /* |
427 | * Remove stale credentials. Avoid sleeping inside the loop. |
428 | */ |
429 | static long |
430 | rpcauth_prune_expired(struct list_head *free, int nr_to_scan) |
431 | { |
432 | struct rpc_cred *cred, *next; |
433 | unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM; |
434 | long freed = 0; |
435 | |
436 | list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) { |
437 | |
438 | if (nr_to_scan-- == 0) |
439 | break; |
440 | if (refcount_read(r: &cred->cr_count) > 1) { |
441 | rpcauth_lru_remove_locked(cred); |
442 | continue; |
443 | } |
444 | /* |
445 | * Enforce a 60 second garbage collection moratorium |
446 | * Note that the cred_unused list must be time-ordered. |
447 | */ |
448 | if (time_in_range(cred->cr_expire, expired, jiffies)) |
449 | continue; |
450 | if (!rpcauth_unhash_cred(cred)) |
451 | continue; |
452 | |
453 | rpcauth_lru_remove_locked(cred); |
454 | freed++; |
455 | list_add_tail(new: &cred->cr_lru, head: free); |
456 | } |
457 | return freed ? freed : SHRINK_STOP; |
458 | } |
459 | |
460 | static unsigned long |
461 | rpcauth_cache_do_shrink(int nr_to_scan) |
462 | { |
463 | LIST_HEAD(free); |
464 | unsigned long freed; |
465 | |
466 | spin_lock(lock: &rpc_credcache_lock); |
467 | freed = rpcauth_prune_expired(free: &free, nr_to_scan); |
468 | spin_unlock(lock: &rpc_credcache_lock); |
469 | rpcauth_destroy_credlist(head: &free); |
470 | |
471 | return freed; |
472 | } |
473 | |
474 | /* |
475 | * Run memory cache shrinker. |
476 | */ |
477 | static unsigned long |
478 | rpcauth_cache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) |
479 | |
480 | { |
481 | if ((sc->gfp_mask & GFP_KERNEL) != GFP_KERNEL) |
482 | return SHRINK_STOP; |
483 | |
484 | /* nothing left, don't come back */ |
485 | if (list_empty(head: &cred_unused)) |
486 | return SHRINK_STOP; |
487 | |
488 | return rpcauth_cache_do_shrink(nr_to_scan: sc->nr_to_scan); |
489 | } |
490 | |
491 | static unsigned long |
492 | rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc) |
493 | |
494 | { |
495 | return number_cred_unused * sysctl_vfs_cache_pressure / 100; |
496 | } |
497 | |
498 | static void |
499 | rpcauth_cache_enforce_limit(void) |
500 | { |
501 | unsigned long diff; |
502 | unsigned int nr_to_scan; |
503 | |
504 | if (number_cred_unused <= auth_max_cred_cachesize) |
505 | return; |
506 | diff = number_cred_unused - auth_max_cred_cachesize; |
507 | nr_to_scan = 100; |
508 | if (diff < nr_to_scan) |
509 | nr_to_scan = diff; |
510 | rpcauth_cache_do_shrink(nr_to_scan); |
511 | } |
512 | |
513 | /* |
514 | * Look up a process' credentials in the authentication cache |
515 | */ |
516 | struct rpc_cred * |
517 | rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred, |
518 | int flags, gfp_t gfp) |
519 | { |
520 | LIST_HEAD(free); |
521 | struct rpc_cred_cache *cache = auth->au_credcache; |
522 | struct rpc_cred *cred = NULL, |
523 | *entry, *new; |
524 | unsigned int nr; |
525 | |
526 | nr = auth->au_ops->hash_cred(acred, cache->hashbits); |
527 | |
528 | rcu_read_lock(); |
529 | hlist_for_each_entry_rcu(entry, &cache->hashtable[nr], cr_hash) { |
530 | if (!entry->cr_ops->crmatch(acred, entry, flags)) |
531 | continue; |
532 | cred = get_rpccred(cred: entry); |
533 | if (cred) |
534 | break; |
535 | } |
536 | rcu_read_unlock(); |
537 | |
538 | if (cred != NULL) |
539 | goto found; |
540 | |
541 | new = auth->au_ops->crcreate(auth, acred, flags, gfp); |
542 | if (IS_ERR(ptr: new)) { |
543 | cred = new; |
544 | goto out; |
545 | } |
546 | |
547 | spin_lock(lock: &cache->lock); |
548 | hlist_for_each_entry(entry, &cache->hashtable[nr], cr_hash) { |
549 | if (!entry->cr_ops->crmatch(acred, entry, flags)) |
550 | continue; |
551 | cred = get_rpccred(cred: entry); |
552 | if (cred) |
553 | break; |
554 | } |
555 | if (cred == NULL) { |
556 | cred = new; |
557 | set_bit(RPCAUTH_CRED_HASHED, addr: &cred->cr_flags); |
558 | refcount_inc(r: &cred->cr_count); |
559 | hlist_add_head_rcu(n: &cred->cr_hash, h: &cache->hashtable[nr]); |
560 | } else |
561 | list_add_tail(new: &new->cr_lru, head: &free); |
562 | spin_unlock(lock: &cache->lock); |
563 | rpcauth_cache_enforce_limit(); |
564 | found: |
565 | if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && |
566 | cred->cr_ops->cr_init != NULL && |
567 | !(flags & RPCAUTH_LOOKUP_NEW)) { |
568 | int res = cred->cr_ops->cr_init(auth, cred); |
569 | if (res < 0) { |
570 | put_rpccred(cred); |
571 | cred = ERR_PTR(error: res); |
572 | } |
573 | } |
574 | rpcauth_destroy_credlist(head: &free); |
575 | out: |
576 | return cred; |
577 | } |
578 | EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache); |
579 | |
580 | struct rpc_cred * |
581 | rpcauth_lookupcred(struct rpc_auth *auth, int flags) |
582 | { |
583 | struct auth_cred acred; |
584 | struct rpc_cred *ret; |
585 | const struct cred *cred = current_cred(); |
586 | |
587 | memset(&acred, 0, sizeof(acred)); |
588 | acred.cred = cred; |
589 | ret = auth->au_ops->lookup_cred(auth, &acred, flags); |
590 | return ret; |
591 | } |
592 | EXPORT_SYMBOL_GPL(rpcauth_lookupcred); |
593 | |
594 | void |
595 | rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred, |
596 | struct rpc_auth *auth, const struct rpc_credops *ops) |
597 | { |
598 | INIT_HLIST_NODE(h: &cred->cr_hash); |
599 | INIT_LIST_HEAD(list: &cred->cr_lru); |
600 | refcount_set(r: &cred->cr_count, n: 1); |
601 | cred->cr_auth = auth; |
602 | cred->cr_flags = 0; |
603 | cred->cr_ops = ops; |
604 | cred->cr_expire = jiffies; |
605 | cred->cr_cred = get_cred(cred: acred->cred); |
606 | } |
607 | EXPORT_SYMBOL_GPL(rpcauth_init_cred); |
608 | |
609 | static struct rpc_cred * |
610 | rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags) |
611 | { |
612 | struct rpc_auth *auth = task->tk_client->cl_auth; |
613 | struct auth_cred acred = { |
614 | .cred = get_task_cred(&init_task), |
615 | }; |
616 | struct rpc_cred *ret; |
617 | |
618 | if (RPC_IS_ASYNC(task)) |
619 | lookupflags |= RPCAUTH_LOOKUP_ASYNC; |
620 | ret = auth->au_ops->lookup_cred(auth, &acred, lookupflags); |
621 | put_cred(cred: acred.cred); |
622 | return ret; |
623 | } |
624 | |
625 | static struct rpc_cred * |
626 | rpcauth_bind_machine_cred(struct rpc_task *task, int lookupflags) |
627 | { |
628 | struct rpc_auth *auth = task->tk_client->cl_auth; |
629 | struct auth_cred acred = { |
630 | .principal = task->tk_client->cl_principal, |
631 | .cred = init_task.cred, |
632 | }; |
633 | |
634 | if (!acred.principal) |
635 | return NULL; |
636 | if (RPC_IS_ASYNC(task)) |
637 | lookupflags |= RPCAUTH_LOOKUP_ASYNC; |
638 | return auth->au_ops->lookup_cred(auth, &acred, lookupflags); |
639 | } |
640 | |
641 | static struct rpc_cred * |
642 | rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags) |
643 | { |
644 | struct rpc_auth *auth = task->tk_client->cl_auth; |
645 | |
646 | return rpcauth_lookupcred(auth, lookupflags); |
647 | } |
648 | |
649 | static int |
650 | rpcauth_bindcred(struct rpc_task *task, const struct cred *cred, int flags) |
651 | { |
652 | struct rpc_rqst *req = task->tk_rqstp; |
653 | struct rpc_cred *new = NULL; |
654 | int lookupflags = 0; |
655 | struct rpc_auth *auth = task->tk_client->cl_auth; |
656 | struct auth_cred acred = { |
657 | .cred = cred, |
658 | }; |
659 | |
660 | if (flags & RPC_TASK_ASYNC) |
661 | lookupflags |= RPCAUTH_LOOKUP_NEW | RPCAUTH_LOOKUP_ASYNC; |
662 | if (task->tk_op_cred) |
663 | /* Task must use exactly this rpc_cred */ |
664 | new = get_rpccred(cred: task->tk_op_cred); |
665 | else if (cred != NULL && cred != &machine_cred) |
666 | new = auth->au_ops->lookup_cred(auth, &acred, lookupflags); |
667 | else if (cred == &machine_cred) |
668 | new = rpcauth_bind_machine_cred(task, lookupflags); |
669 | |
670 | /* If machine cred couldn't be bound, try a root cred */ |
671 | if (new) |
672 | ; |
673 | else if (cred == &machine_cred) |
674 | new = rpcauth_bind_root_cred(task, lookupflags); |
675 | else if (flags & RPC_TASK_NULLCREDS) |
676 | new = authnull_ops.lookup_cred(NULL, NULL, 0); |
677 | else |
678 | new = rpcauth_bind_new_cred(task, lookupflags); |
679 | if (IS_ERR(ptr: new)) |
680 | return PTR_ERR(ptr: new); |
681 | put_rpccred(req->rq_cred); |
682 | req->rq_cred = new; |
683 | return 0; |
684 | } |
685 | |
686 | void |
687 | put_rpccred(struct rpc_cred *cred) |
688 | { |
689 | if (cred == NULL) |
690 | return; |
691 | rcu_read_lock(); |
692 | if (refcount_dec_and_test(r: &cred->cr_count)) |
693 | goto destroy; |
694 | if (refcount_read(r: &cred->cr_count) != 1 || |
695 | !test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags)) |
696 | goto out; |
697 | if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) { |
698 | cred->cr_expire = jiffies; |
699 | rpcauth_lru_add(cred); |
700 | /* Race breaker */ |
701 | if (unlikely(!test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags))) |
702 | rpcauth_lru_remove(cred); |
703 | } else if (rpcauth_unhash_cred(cred)) { |
704 | rpcauth_lru_remove(cred); |
705 | if (refcount_dec_and_test(r: &cred->cr_count)) |
706 | goto destroy; |
707 | } |
708 | out: |
709 | rcu_read_unlock(); |
710 | return; |
711 | destroy: |
712 | rcu_read_unlock(); |
713 | cred->cr_ops->crdestroy(cred); |
714 | } |
715 | EXPORT_SYMBOL_GPL(put_rpccred); |
716 | |
717 | /** |
718 | * rpcauth_marshcred - Append RPC credential to end of @xdr |
719 | * @task: controlling RPC task |
720 | * @xdr: xdr_stream containing initial portion of RPC Call header |
721 | * |
722 | * On success, an appropriate verifier is added to @xdr, @xdr is |
723 | * updated to point past the verifier, and zero is returned. |
724 | * Otherwise, @xdr is in an undefined state and a negative errno |
725 | * is returned. |
726 | */ |
727 | int rpcauth_marshcred(struct rpc_task *task, struct xdr_stream *xdr) |
728 | { |
729 | const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops; |
730 | |
731 | return ops->crmarshal(task, xdr); |
732 | } |
733 | |
734 | /** |
735 | * rpcauth_wrap_req_encode - XDR encode the RPC procedure |
736 | * @task: controlling RPC task |
737 | * @xdr: stream where on-the-wire bytes are to be marshalled |
738 | * |
739 | * On success, @xdr contains the encoded and wrapped message. |
740 | * Otherwise, @xdr is in an undefined state. |
741 | */ |
742 | int rpcauth_wrap_req_encode(struct rpc_task *task, struct xdr_stream *xdr) |
743 | { |
744 | kxdreproc_t encode = task->tk_msg.rpc_proc->p_encode; |
745 | |
746 | encode(task->tk_rqstp, xdr, task->tk_msg.rpc_argp); |
747 | return 0; |
748 | } |
749 | EXPORT_SYMBOL_GPL(rpcauth_wrap_req_encode); |
750 | |
751 | /** |
752 | * rpcauth_wrap_req - XDR encode and wrap the RPC procedure |
753 | * @task: controlling RPC task |
754 | * @xdr: stream where on-the-wire bytes are to be marshalled |
755 | * |
756 | * On success, @xdr contains the encoded and wrapped message, |
757 | * and zero is returned. Otherwise, @xdr is in an undefined |
758 | * state and a negative errno is returned. |
759 | */ |
760 | int rpcauth_wrap_req(struct rpc_task *task, struct xdr_stream *xdr) |
761 | { |
762 | const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops; |
763 | |
764 | return ops->crwrap_req(task, xdr); |
765 | } |
766 | |
767 | /** |
768 | * rpcauth_checkverf - Validate verifier in RPC Reply header |
769 | * @task: controlling RPC task |
770 | * @xdr: xdr_stream containing RPC Reply header |
771 | * |
772 | * Return values: |
773 | * %0: Verifier is valid. @xdr now points past the verifier. |
774 | * %-EIO: Verifier is corrupted or message ended early. |
775 | * %-EACCES: Verifier is intact but not valid. |
776 | * %-EPROTONOSUPPORT: Server does not support the requested auth type. |
777 | * |
778 | * When a negative errno is returned, @xdr is left in an undefined |
779 | * state. |
780 | */ |
781 | int |
782 | rpcauth_checkverf(struct rpc_task *task, struct xdr_stream *xdr) |
783 | { |
784 | const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops; |
785 | |
786 | return ops->crvalidate(task, xdr); |
787 | } |
788 | |
789 | /** |
790 | * rpcauth_unwrap_resp_decode - Invoke XDR decode function |
791 | * @task: controlling RPC task |
792 | * @xdr: stream where the Reply message resides |
793 | * |
794 | * Returns zero on success; otherwise a negative errno is returned. |
795 | */ |
796 | int |
797 | rpcauth_unwrap_resp_decode(struct rpc_task *task, struct xdr_stream *xdr) |
798 | { |
799 | kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; |
800 | |
801 | return decode(task->tk_rqstp, xdr, task->tk_msg.rpc_resp); |
802 | } |
803 | EXPORT_SYMBOL_GPL(rpcauth_unwrap_resp_decode); |
804 | |
805 | /** |
806 | * rpcauth_unwrap_resp - Invoke unwrap and decode function for the cred |
807 | * @task: controlling RPC task |
808 | * @xdr: stream where the Reply message resides |
809 | * |
810 | * Returns zero on success; otherwise a negative errno is returned. |
811 | */ |
812 | int |
813 | rpcauth_unwrap_resp(struct rpc_task *task, struct xdr_stream *xdr) |
814 | { |
815 | const struct rpc_credops *ops = task->tk_rqstp->rq_cred->cr_ops; |
816 | |
817 | return ops->crunwrap_resp(task, xdr); |
818 | } |
819 | |
820 | bool |
821 | rpcauth_xmit_need_reencode(struct rpc_task *task) |
822 | { |
823 | struct rpc_cred *cred = task->tk_rqstp->rq_cred; |
824 | |
825 | if (!cred || !cred->cr_ops->crneed_reencode) |
826 | return false; |
827 | return cred->cr_ops->crneed_reencode(task); |
828 | } |
829 | |
830 | int |
831 | rpcauth_refreshcred(struct rpc_task *task) |
832 | { |
833 | struct rpc_cred *cred; |
834 | int err; |
835 | |
836 | cred = task->tk_rqstp->rq_cred; |
837 | if (cred == NULL) { |
838 | err = rpcauth_bindcred(task, cred: task->tk_msg.rpc_cred, flags: task->tk_flags); |
839 | if (err < 0) |
840 | goto out; |
841 | cred = task->tk_rqstp->rq_cred; |
842 | } |
843 | |
844 | err = cred->cr_ops->crrefresh(task); |
845 | out: |
846 | if (err < 0) |
847 | task->tk_status = err; |
848 | return err; |
849 | } |
850 | |
851 | void |
852 | rpcauth_invalcred(struct rpc_task *task) |
853 | { |
854 | struct rpc_cred *cred = task->tk_rqstp->rq_cred; |
855 | |
856 | if (cred) |
857 | clear_bit(RPCAUTH_CRED_UPTODATE, addr: &cred->cr_flags); |
858 | } |
859 | |
860 | int |
861 | rpcauth_uptodatecred(struct rpc_task *task) |
862 | { |
863 | struct rpc_cred *cred = task->tk_rqstp->rq_cred; |
864 | |
865 | return cred == NULL || |
866 | test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0; |
867 | } |
868 | |
869 | static struct shrinker *rpc_cred_shrinker; |
870 | |
871 | int __init rpcauth_init_module(void) |
872 | { |
873 | int err; |
874 | |
875 | err = rpc_init_authunix(); |
876 | if (err < 0) |
877 | goto out1; |
878 | rpc_cred_shrinker = shrinker_alloc(flags: 0, fmt: "sunrpc_cred" ); |
879 | if (!rpc_cred_shrinker) { |
880 | err = -ENOMEM; |
881 | goto out2; |
882 | } |
883 | |
884 | rpc_cred_shrinker->count_objects = rpcauth_cache_shrink_count; |
885 | rpc_cred_shrinker->scan_objects = rpcauth_cache_shrink_scan; |
886 | |
887 | shrinker_register(shrinker: rpc_cred_shrinker); |
888 | |
889 | return 0; |
890 | out2: |
891 | rpc_destroy_authunix(); |
892 | out1: |
893 | return err; |
894 | } |
895 | |
896 | void rpcauth_remove_module(void) |
897 | { |
898 | rpc_destroy_authunix(); |
899 | shrinker_free(shrinker: rpc_cred_shrinker); |
900 | } |
901 | |