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