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/sunrpc/gss_api.h> 17 #include <linux/spinlock.h> 18 19 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 20 # define RPCDBG_FACILITY RPCDBG_AUTH 21 #endif 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 DEFINE_SPINLOCK(rpc_authflavor_lock); 33 static const struct rpc_authops *auth_flavors[RPC_AUTH_MAXFLAVOR] = { 34 &authnull_ops, /* AUTH_NULL */ 35 &authunix_ops, /* AUTH_UNIX */ 36 NULL, /* others can be loadable modules */ 37 }; 38 39 static LIST_HEAD(cred_unused); 40 static unsigned long number_cred_unused; 41 42 #define MAX_HASHTABLE_BITS (14) 43 static int param_set_hashtbl_sz(const char *val, const struct kernel_param *kp) 44 { 45 unsigned long num; 46 unsigned int nbits; 47 int ret; 48 49 if (!val) 50 goto out_inval; 51 ret = kstrtoul(val, 0, &num); 52 if (ret == -EINVAL) 53 goto out_inval; 54 nbits = fls(num - 1); 55 if (nbits > MAX_HASHTABLE_BITS || nbits < 2) 56 goto out_inval; 57 *(unsigned int *)kp->arg = nbits; 58 return 0; 59 out_inval: 60 return -EINVAL; 61 } 62 63 static int param_get_hashtbl_sz(char *buffer, const struct kernel_param *kp) 64 { 65 unsigned int nbits; 66 67 nbits = *(unsigned int *)kp->arg; 68 return sprintf(buffer, "%u", 1U << nbits); 69 } 70 71 #define param_check_hashtbl_sz(name, p) __param_check(name, p, unsigned int); 72 73 static const struct kernel_param_ops param_ops_hashtbl_sz = { 74 .set = param_set_hashtbl_sz, 75 .get = param_get_hashtbl_sz, 76 }; 77 78 module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644); 79 MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size"); 80 81 static unsigned long auth_max_cred_cachesize = ULONG_MAX; 82 module_param(auth_max_cred_cachesize, ulong, 0644); 83 MODULE_PARM_DESC(auth_max_cred_cachesize, "RPC credential maximum total cache size"); 84 85 static u32 86 pseudoflavor_to_flavor(u32 flavor) { 87 if (flavor > RPC_AUTH_MAXFLAVOR) 88 return RPC_AUTH_GSS; 89 return flavor; 90 } 91 92 int 93 rpcauth_register(const struct rpc_authops *ops) 94 { 95 rpc_authflavor_t flavor; 96 int ret = -EPERM; 97 98 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR) 99 return -EINVAL; 100 spin_lock(&rpc_authflavor_lock); 101 if (auth_flavors[flavor] == NULL) { 102 auth_flavors[flavor] = ops; 103 ret = 0; 104 } 105 spin_unlock(&rpc_authflavor_lock); 106 return ret; 107 } 108 EXPORT_SYMBOL_GPL(rpcauth_register); 109 110 int 111 rpcauth_unregister(const struct rpc_authops *ops) 112 { 113 rpc_authflavor_t flavor; 114 int ret = -EPERM; 115 116 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR) 117 return -EINVAL; 118 spin_lock(&rpc_authflavor_lock); 119 if (auth_flavors[flavor] == ops) { 120 auth_flavors[flavor] = NULL; 121 ret = 0; 122 } 123 spin_unlock(&rpc_authflavor_lock); 124 return ret; 125 } 126 EXPORT_SYMBOL_GPL(rpcauth_unregister); 127 128 /** 129 * rpcauth_get_pseudoflavor - check if security flavor is supported 130 * @flavor: a security flavor 131 * @info: a GSS mech OID, quality of protection, and service value 132 * 133 * Verifies that an appropriate kernel module is available or already loaded. 134 * Returns an equivalent pseudoflavor, or RPC_AUTH_MAXFLAVOR if "flavor" is 135 * not supported locally. 136 */ 137 rpc_authflavor_t 138 rpcauth_get_pseudoflavor(rpc_authflavor_t flavor, struct rpcsec_gss_info *info) 139 { 140 const struct rpc_authops *ops; 141 rpc_authflavor_t pseudoflavor; 142 143 ops = auth_flavors[flavor]; 144 if (ops == NULL) 145 request_module("rpc-auth-%u", flavor); 146 spin_lock(&rpc_authflavor_lock); 147 ops = auth_flavors[flavor]; 148 if (ops == NULL || !try_module_get(ops->owner)) { 149 spin_unlock(&rpc_authflavor_lock); 150 return RPC_AUTH_MAXFLAVOR; 151 } 152 spin_unlock(&rpc_authflavor_lock); 153 154 pseudoflavor = flavor; 155 if (ops->info2flavor != NULL) 156 pseudoflavor = ops->info2flavor(info); 157 158 module_put(ops->owner); 159 return pseudoflavor; 160 } 161 EXPORT_SYMBOL_GPL(rpcauth_get_pseudoflavor); 162 163 /** 164 * rpcauth_get_gssinfo - find GSS tuple matching a GSS pseudoflavor 165 * @pseudoflavor: GSS pseudoflavor to match 166 * @info: rpcsec_gss_info structure to fill in 167 * 168 * Returns zero and fills in "info" if pseudoflavor matches a 169 * supported mechanism. 170 */ 171 int 172 rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info) 173 { 174 rpc_authflavor_t flavor = pseudoflavor_to_flavor(pseudoflavor); 175 const struct rpc_authops *ops; 176 int result; 177 178 if (flavor >= RPC_AUTH_MAXFLAVOR) 179 return -EINVAL; 180 181 ops = auth_flavors[flavor]; 182 if (ops == NULL) 183 request_module("rpc-auth-%u", flavor); 184 spin_lock(&rpc_authflavor_lock); 185 ops = auth_flavors[flavor]; 186 if (ops == NULL || !try_module_get(ops->owner)) { 187 spin_unlock(&rpc_authflavor_lock); 188 return -ENOENT; 189 } 190 spin_unlock(&rpc_authflavor_lock); 191 192 result = -ENOENT; 193 if (ops->flavor2info != NULL) 194 result = ops->flavor2info(pseudoflavor, info); 195 196 module_put(ops->owner); 197 return result; 198 } 199 EXPORT_SYMBOL_GPL(rpcauth_get_gssinfo); 200 201 /** 202 * rpcauth_list_flavors - discover registered flavors and pseudoflavors 203 * @array: array to fill in 204 * @size: size of "array" 205 * 206 * Returns the number of array items filled in, or a negative errno. 207 * 208 * The returned array is not sorted by any policy. Callers should not 209 * rely on the order of the items in the returned array. 210 */ 211 int 212 rpcauth_list_flavors(rpc_authflavor_t *array, int size) 213 { 214 rpc_authflavor_t flavor; 215 int result = 0; 216 217 spin_lock(&rpc_authflavor_lock); 218 for (flavor = 0; flavor < RPC_AUTH_MAXFLAVOR; flavor++) { 219 const struct rpc_authops *ops = auth_flavors[flavor]; 220 rpc_authflavor_t pseudos[4]; 221 int i, len; 222 223 if (result >= size) { 224 result = -ENOMEM; 225 break; 226 } 227 228 if (ops == NULL) 229 continue; 230 if (ops->list_pseudoflavors == NULL) { 231 array[result++] = ops->au_flavor; 232 continue; 233 } 234 len = ops->list_pseudoflavors(pseudos, ARRAY_SIZE(pseudos)); 235 if (len < 0) { 236 result = len; 237 break; 238 } 239 for (i = 0; i < len; i++) { 240 if (result >= size) { 241 result = -ENOMEM; 242 break; 243 } 244 array[result++] = pseudos[i]; 245 } 246 } 247 spin_unlock(&rpc_authflavor_lock); 248 249 dprintk("RPC: %s returns %d\n", __func__, result); 250 return result; 251 } 252 EXPORT_SYMBOL_GPL(rpcauth_list_flavors); 253 254 struct rpc_auth * 255 rpcauth_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt) 256 { 257 struct rpc_auth *auth; 258 const struct rpc_authops *ops; 259 u32 flavor = pseudoflavor_to_flavor(args->pseudoflavor); 260 261 auth = ERR_PTR(-EINVAL); 262 if (flavor >= RPC_AUTH_MAXFLAVOR) 263 goto out; 264 265 if ((ops = auth_flavors[flavor]) == NULL) 266 request_module("rpc-auth-%u", flavor); 267 spin_lock(&rpc_authflavor_lock); 268 ops = auth_flavors[flavor]; 269 if (ops == NULL || !try_module_get(ops->owner)) { 270 spin_unlock(&rpc_authflavor_lock); 271 goto out; 272 } 273 spin_unlock(&rpc_authflavor_lock); 274 auth = ops->create(args, clnt); 275 module_put(ops->owner); 276 if (IS_ERR(auth)) 277 return auth; 278 if (clnt->cl_auth) 279 rpcauth_release(clnt->cl_auth); 280 clnt->cl_auth = auth; 281 282 out: 283 return auth; 284 } 285 EXPORT_SYMBOL_GPL(rpcauth_create); 286 287 void 288 rpcauth_release(struct rpc_auth *auth) 289 { 290 if (!atomic_dec_and_test(&auth->au_count)) 291 return; 292 auth->au_ops->destroy(auth); 293 } 294 295 static DEFINE_SPINLOCK(rpc_credcache_lock); 296 297 static void 298 rpcauth_unhash_cred_locked(struct rpc_cred *cred) 299 { 300 hlist_del_rcu(&cred->cr_hash); 301 smp_mb__before_atomic(); 302 clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags); 303 } 304 305 static int 306 rpcauth_unhash_cred(struct rpc_cred *cred) 307 { 308 spinlock_t *cache_lock; 309 int ret; 310 311 cache_lock = &cred->cr_auth->au_credcache->lock; 312 spin_lock(cache_lock); 313 ret = atomic_read(&cred->cr_count) == 0; 314 if (ret) 315 rpcauth_unhash_cred_locked(cred); 316 spin_unlock(cache_lock); 317 return ret; 318 } 319 320 /* 321 * Initialize RPC credential cache 322 */ 323 int 324 rpcauth_init_credcache(struct rpc_auth *auth) 325 { 326 struct rpc_cred_cache *new; 327 unsigned int hashsize; 328 329 new = kmalloc(sizeof(*new), GFP_KERNEL); 330 if (!new) 331 goto out_nocache; 332 new->hashbits = auth_hashbits; 333 hashsize = 1U << new->hashbits; 334 new->hashtable = kcalloc(hashsize, sizeof(new->hashtable[0]), GFP_KERNEL); 335 if (!new->hashtable) 336 goto out_nohashtbl; 337 spin_lock_init(&new->lock); 338 auth->au_credcache = new; 339 return 0; 340 out_nohashtbl: 341 kfree(new); 342 out_nocache: 343 return -ENOMEM; 344 } 345 EXPORT_SYMBOL_GPL(rpcauth_init_credcache); 346 347 /* 348 * Setup a credential key lifetime timeout notification 349 */ 350 int 351 rpcauth_key_timeout_notify(struct rpc_auth *auth, struct rpc_cred *cred) 352 { 353 if (!cred->cr_auth->au_ops->key_timeout) 354 return 0; 355 return cred->cr_auth->au_ops->key_timeout(auth, cred); 356 } 357 EXPORT_SYMBOL_GPL(rpcauth_key_timeout_notify); 358 359 bool 360 rpcauth_cred_key_to_expire(struct rpc_auth *auth, struct rpc_cred *cred) 361 { 362 if (auth->au_flags & RPCAUTH_AUTH_NO_CRKEY_TIMEOUT) 363 return false; 364 if (!cred->cr_ops->crkey_to_expire) 365 return false; 366 return cred->cr_ops->crkey_to_expire(cred); 367 } 368 EXPORT_SYMBOL_GPL(rpcauth_cred_key_to_expire); 369 370 char * 371 rpcauth_stringify_acceptor(struct rpc_cred *cred) 372 { 373 if (!cred->cr_ops->crstringify_acceptor) 374 return NULL; 375 return cred->cr_ops->crstringify_acceptor(cred); 376 } 377 EXPORT_SYMBOL_GPL(rpcauth_stringify_acceptor); 378 379 /* 380 * Destroy a list of credentials 381 */ 382 static inline 383 void rpcauth_destroy_credlist(struct list_head *head) 384 { 385 struct rpc_cred *cred; 386 387 while (!list_empty(head)) { 388 cred = list_entry(head->next, struct rpc_cred, cr_lru); 389 list_del_init(&cred->cr_lru); 390 put_rpccred(cred); 391 } 392 } 393 394 /* 395 * Clear the RPC credential cache, and delete those credentials 396 * that are not referenced. 397 */ 398 void 399 rpcauth_clear_credcache(struct rpc_cred_cache *cache) 400 { 401 LIST_HEAD(free); 402 struct hlist_head *head; 403 struct rpc_cred *cred; 404 unsigned int hashsize = 1U << cache->hashbits; 405 int i; 406 407 spin_lock(&rpc_credcache_lock); 408 spin_lock(&cache->lock); 409 for (i = 0; i < hashsize; i++) { 410 head = &cache->hashtable[i]; 411 while (!hlist_empty(head)) { 412 cred = hlist_entry(head->first, struct rpc_cred, cr_hash); 413 get_rpccred(cred); 414 if (!list_empty(&cred->cr_lru)) { 415 list_del(&cred->cr_lru); 416 number_cred_unused--; 417 } 418 list_add_tail(&cred->cr_lru, &free); 419 rpcauth_unhash_cred_locked(cred); 420 } 421 } 422 spin_unlock(&cache->lock); 423 spin_unlock(&rpc_credcache_lock); 424 rpcauth_destroy_credlist(&free); 425 } 426 427 /* 428 * Destroy the RPC credential cache 429 */ 430 void 431 rpcauth_destroy_credcache(struct rpc_auth *auth) 432 { 433 struct rpc_cred_cache *cache = auth->au_credcache; 434 435 if (cache) { 436 auth->au_credcache = NULL; 437 rpcauth_clear_credcache(cache); 438 kfree(cache->hashtable); 439 kfree(cache); 440 } 441 } 442 EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache); 443 444 445 #define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ) 446 447 /* 448 * Remove stale credentials. Avoid sleeping inside the loop. 449 */ 450 static long 451 rpcauth_prune_expired(struct list_head *free, int nr_to_scan) 452 { 453 spinlock_t *cache_lock; 454 struct rpc_cred *cred, *next; 455 unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM; 456 long freed = 0; 457 458 list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) { 459 460 if (nr_to_scan-- == 0) 461 break; 462 /* 463 * Enforce a 60 second garbage collection moratorium 464 * Note that the cred_unused list must be time-ordered. 465 */ 466 if (time_in_range(cred->cr_expire, expired, jiffies) && 467 test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) { 468 freed = SHRINK_STOP; 469 break; 470 } 471 472 list_del_init(&cred->cr_lru); 473 number_cred_unused--; 474 freed++; 475 if (atomic_read(&cred->cr_count) != 0) 476 continue; 477 478 cache_lock = &cred->cr_auth->au_credcache->lock; 479 spin_lock(cache_lock); 480 if (atomic_read(&cred->cr_count) == 0) { 481 get_rpccred(cred); 482 list_add_tail(&cred->cr_lru, free); 483 rpcauth_unhash_cred_locked(cred); 484 } 485 spin_unlock(cache_lock); 486 } 487 return freed; 488 } 489 490 static unsigned long 491 rpcauth_cache_do_shrink(int nr_to_scan) 492 { 493 LIST_HEAD(free); 494 unsigned long freed; 495 496 spin_lock(&rpc_credcache_lock); 497 freed = rpcauth_prune_expired(&free, nr_to_scan); 498 spin_unlock(&rpc_credcache_lock); 499 rpcauth_destroy_credlist(&free); 500 501 return freed; 502 } 503 504 /* 505 * Run memory cache shrinker. 506 */ 507 static unsigned long 508 rpcauth_cache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) 509 510 { 511 if ((sc->gfp_mask & GFP_KERNEL) != GFP_KERNEL) 512 return SHRINK_STOP; 513 514 /* nothing left, don't come back */ 515 if (list_empty(&cred_unused)) 516 return SHRINK_STOP; 517 518 return rpcauth_cache_do_shrink(sc->nr_to_scan); 519 } 520 521 static unsigned long 522 rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc) 523 524 { 525 return number_cred_unused * sysctl_vfs_cache_pressure / 100; 526 } 527 528 static void 529 rpcauth_cache_enforce_limit(void) 530 { 531 unsigned long diff; 532 unsigned int nr_to_scan; 533 534 if (number_cred_unused <= auth_max_cred_cachesize) 535 return; 536 diff = number_cred_unused - auth_max_cred_cachesize; 537 nr_to_scan = 100; 538 if (diff < nr_to_scan) 539 nr_to_scan = diff; 540 rpcauth_cache_do_shrink(nr_to_scan); 541 } 542 543 /* 544 * Look up a process' credentials in the authentication cache 545 */ 546 struct rpc_cred * 547 rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred, 548 int flags, gfp_t gfp) 549 { 550 LIST_HEAD(free); 551 struct rpc_cred_cache *cache = auth->au_credcache; 552 struct rpc_cred *cred = NULL, 553 *entry, *new; 554 unsigned int nr; 555 556 nr = auth->au_ops->hash_cred(acred, cache->hashbits); 557 558 rcu_read_lock(); 559 hlist_for_each_entry_rcu(entry, &cache->hashtable[nr], cr_hash) { 560 if (!entry->cr_ops->crmatch(acred, entry, flags)) 561 continue; 562 if (flags & RPCAUTH_LOOKUP_RCU) { 563 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) && 564 !test_bit(RPCAUTH_CRED_NEW, &entry->cr_flags)) 565 cred = entry; 566 break; 567 } 568 spin_lock(&cache->lock); 569 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) { 570 spin_unlock(&cache->lock); 571 continue; 572 } 573 cred = get_rpccred(entry); 574 spin_unlock(&cache->lock); 575 break; 576 } 577 rcu_read_unlock(); 578 579 if (cred != NULL) 580 goto found; 581 582 if (flags & RPCAUTH_LOOKUP_RCU) 583 return ERR_PTR(-ECHILD); 584 585 new = auth->au_ops->crcreate(auth, acred, flags, gfp); 586 if (IS_ERR(new)) { 587 cred = new; 588 goto out; 589 } 590 591 spin_lock(&cache->lock); 592 hlist_for_each_entry(entry, &cache->hashtable[nr], cr_hash) { 593 if (!entry->cr_ops->crmatch(acred, entry, flags)) 594 continue; 595 cred = get_rpccred(entry); 596 break; 597 } 598 if (cred == NULL) { 599 cred = new; 600 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags); 601 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]); 602 } else 603 list_add_tail(&new->cr_lru, &free); 604 spin_unlock(&cache->lock); 605 rpcauth_cache_enforce_limit(); 606 found: 607 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 608 cred->cr_ops->cr_init != NULL && 609 !(flags & RPCAUTH_LOOKUP_NEW)) { 610 int res = cred->cr_ops->cr_init(auth, cred); 611 if (res < 0) { 612 put_rpccred(cred); 613 cred = ERR_PTR(res); 614 } 615 } 616 rpcauth_destroy_credlist(&free); 617 out: 618 return cred; 619 } 620 EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache); 621 622 struct rpc_cred * 623 rpcauth_lookupcred(struct rpc_auth *auth, int flags) 624 { 625 struct auth_cred acred; 626 struct rpc_cred *ret; 627 const struct cred *cred = current_cred(); 628 629 dprintk("RPC: looking up %s cred\n", 630 auth->au_ops->au_name); 631 632 memset(&acred, 0, sizeof(acred)); 633 acred.uid = cred->fsuid; 634 acred.gid = cred->fsgid; 635 acred.group_info = cred->group_info; 636 ret = auth->au_ops->lookup_cred(auth, &acred, flags); 637 return ret; 638 } 639 EXPORT_SYMBOL_GPL(rpcauth_lookupcred); 640 641 void 642 rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred, 643 struct rpc_auth *auth, const struct rpc_credops *ops) 644 { 645 INIT_HLIST_NODE(&cred->cr_hash); 646 INIT_LIST_HEAD(&cred->cr_lru); 647 atomic_set(&cred->cr_count, 1); 648 cred->cr_auth = auth; 649 cred->cr_ops = ops; 650 cred->cr_expire = jiffies; 651 cred->cr_uid = acred->uid; 652 } 653 EXPORT_SYMBOL_GPL(rpcauth_init_cred); 654 655 struct rpc_cred * 656 rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags) 657 { 658 dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid, 659 cred->cr_auth->au_ops->au_name, cred); 660 return get_rpccred(cred); 661 } 662 EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred); 663 664 static struct rpc_cred * 665 rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags) 666 { 667 struct rpc_auth *auth = task->tk_client->cl_auth; 668 struct auth_cred acred = { 669 .uid = GLOBAL_ROOT_UID, 670 .gid = GLOBAL_ROOT_GID, 671 }; 672 673 dprintk("RPC: %5u looking up %s cred\n", 674 task->tk_pid, task->tk_client->cl_auth->au_ops->au_name); 675 return auth->au_ops->lookup_cred(auth, &acred, lookupflags); 676 } 677 678 static struct rpc_cred * 679 rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags) 680 { 681 struct rpc_auth *auth = task->tk_client->cl_auth; 682 683 dprintk("RPC: %5u looking up %s cred\n", 684 task->tk_pid, auth->au_ops->au_name); 685 return rpcauth_lookupcred(auth, lookupflags); 686 } 687 688 static int 689 rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags) 690 { 691 struct rpc_rqst *req = task->tk_rqstp; 692 struct rpc_cred *new; 693 int lookupflags = 0; 694 695 if (flags & RPC_TASK_ASYNC) 696 lookupflags |= RPCAUTH_LOOKUP_NEW; 697 if (cred != NULL) 698 new = cred->cr_ops->crbind(task, cred, lookupflags); 699 else if (flags & RPC_TASK_ROOTCREDS) 700 new = rpcauth_bind_root_cred(task, lookupflags); 701 else 702 new = rpcauth_bind_new_cred(task, lookupflags); 703 if (IS_ERR(new)) 704 return PTR_ERR(new); 705 put_rpccred(req->rq_cred); 706 req->rq_cred = new; 707 return 0; 708 } 709 710 void 711 put_rpccred(struct rpc_cred *cred) 712 { 713 if (cred == NULL) 714 return; 715 /* Fast path for unhashed credentials */ 716 if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) { 717 if (atomic_dec_and_test(&cred->cr_count)) 718 cred->cr_ops->crdestroy(cred); 719 return; 720 } 721 722 if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock)) 723 return; 724 if (!list_empty(&cred->cr_lru)) { 725 number_cred_unused--; 726 list_del_init(&cred->cr_lru); 727 } 728 if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) { 729 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) { 730 cred->cr_expire = jiffies; 731 list_add_tail(&cred->cr_lru, &cred_unused); 732 number_cred_unused++; 733 goto out_nodestroy; 734 } 735 if (!rpcauth_unhash_cred(cred)) { 736 /* We were hashed and someone looked us up... */ 737 goto out_nodestroy; 738 } 739 } 740 spin_unlock(&rpc_credcache_lock); 741 cred->cr_ops->crdestroy(cred); 742 return; 743 out_nodestroy: 744 spin_unlock(&rpc_credcache_lock); 745 } 746 EXPORT_SYMBOL_GPL(put_rpccred); 747 748 __be32 * 749 rpcauth_marshcred(struct rpc_task *task, __be32 *p) 750 { 751 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 752 753 dprintk("RPC: %5u marshaling %s cred %p\n", 754 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 755 756 return cred->cr_ops->crmarshal(task, p); 757 } 758 759 __be32 * 760 rpcauth_checkverf(struct rpc_task *task, __be32 *p) 761 { 762 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 763 764 dprintk("RPC: %5u validating %s cred %p\n", 765 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 766 767 return cred->cr_ops->crvalidate(task, p); 768 } 769 770 static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp, 771 __be32 *data, void *obj) 772 { 773 struct xdr_stream xdr; 774 775 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data); 776 encode(rqstp, &xdr, obj); 777 } 778 779 int 780 rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp, 781 __be32 *data, void *obj) 782 { 783 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 784 785 dprintk("RPC: %5u using %s cred %p to wrap rpc data\n", 786 task->tk_pid, cred->cr_ops->cr_name, cred); 787 if (cred->cr_ops->crwrap_req) 788 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj); 789 /* By default, we encode the arguments normally. */ 790 rpcauth_wrap_req_encode(encode, rqstp, data, obj); 791 return 0; 792 } 793 794 static int 795 rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp, 796 __be32 *data, void *obj) 797 { 798 struct xdr_stream xdr; 799 800 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data); 801 return decode(rqstp, &xdr, obj); 802 } 803 804 int 805 rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp, 806 __be32 *data, void *obj) 807 { 808 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 809 810 dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n", 811 task->tk_pid, cred->cr_ops->cr_name, cred); 812 if (cred->cr_ops->crunwrap_resp) 813 return cred->cr_ops->crunwrap_resp(task, decode, rqstp, 814 data, obj); 815 /* By default, we decode the arguments normally. */ 816 return rpcauth_unwrap_req_decode(decode, rqstp, data, obj); 817 } 818 819 int 820 rpcauth_refreshcred(struct rpc_task *task) 821 { 822 struct rpc_cred *cred; 823 int err; 824 825 cred = task->tk_rqstp->rq_cred; 826 if (cred == NULL) { 827 err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags); 828 if (err < 0) 829 goto out; 830 cred = task->tk_rqstp->rq_cred; 831 } 832 dprintk("RPC: %5u refreshing %s cred %p\n", 833 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 834 835 err = cred->cr_ops->crrefresh(task); 836 out: 837 if (err < 0) 838 task->tk_status = err; 839 return err; 840 } 841 842 void 843 rpcauth_invalcred(struct rpc_task *task) 844 { 845 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 846 847 dprintk("RPC: %5u invalidating %s cred %p\n", 848 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 849 if (cred) 850 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 851 } 852 853 int 854 rpcauth_uptodatecred(struct rpc_task *task) 855 { 856 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 857 858 return cred == NULL || 859 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0; 860 } 861 862 static struct shrinker rpc_cred_shrinker = { 863 .count_objects = rpcauth_cache_shrink_count, 864 .scan_objects = rpcauth_cache_shrink_scan, 865 .seeks = DEFAULT_SEEKS, 866 }; 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 err = rpc_init_generic_auth(); 876 if (err < 0) 877 goto out2; 878 err = register_shrinker(&rpc_cred_shrinker); 879 if (err < 0) 880 goto out3; 881 return 0; 882 out3: 883 rpc_destroy_generic_auth(); 884 out2: 885 rpc_destroy_authunix(); 886 out1: 887 return err; 888 } 889 890 void rpcauth_remove_module(void) 891 { 892 rpc_destroy_authunix(); 893 rpc_destroy_generic_auth(); 894 unregister_shrinker(&rpc_cred_shrinker); 895 } 896