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); 55 if (num > (1U << nbits)) 56 nbits++; 57 if (nbits > MAX_HASHTABLE_BITS || nbits < 2) 58 goto out_inval; 59 *(unsigned int *)kp->arg = nbits; 60 return 0; 61 out_inval: 62 return -EINVAL; 63 } 64 65 static int param_get_hashtbl_sz(char *buffer, const struct kernel_param *kp) 66 { 67 unsigned int nbits; 68 69 nbits = *(unsigned int *)kp->arg; 70 return sprintf(buffer, "%u", 1U << nbits); 71 } 72 73 #define param_check_hashtbl_sz(name, p) __param_check(name, p, unsigned int); 74 75 static const struct kernel_param_ops param_ops_hashtbl_sz = { 76 .set = param_set_hashtbl_sz, 77 .get = param_get_hashtbl_sz, 78 }; 79 80 module_param_named(auth_hashtable_size, auth_hashbits, hashtbl_sz, 0644); 81 MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size"); 82 83 static unsigned long auth_max_cred_cachesize = ULONG_MAX; 84 module_param(auth_max_cred_cachesize, ulong, 0644); 85 MODULE_PARM_DESC(auth_max_cred_cachesize, "RPC credential maximum total cache size"); 86 87 static u32 88 pseudoflavor_to_flavor(u32 flavor) { 89 if (flavor > RPC_AUTH_MAXFLAVOR) 90 return RPC_AUTH_GSS; 91 return flavor; 92 } 93 94 int 95 rpcauth_register(const struct rpc_authops *ops) 96 { 97 rpc_authflavor_t flavor; 98 int ret = -EPERM; 99 100 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR) 101 return -EINVAL; 102 spin_lock(&rpc_authflavor_lock); 103 if (auth_flavors[flavor] == NULL) { 104 auth_flavors[flavor] = ops; 105 ret = 0; 106 } 107 spin_unlock(&rpc_authflavor_lock); 108 return ret; 109 } 110 EXPORT_SYMBOL_GPL(rpcauth_register); 111 112 int 113 rpcauth_unregister(const struct rpc_authops *ops) 114 { 115 rpc_authflavor_t flavor; 116 int ret = -EPERM; 117 118 if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR) 119 return -EINVAL; 120 spin_lock(&rpc_authflavor_lock); 121 if (auth_flavors[flavor] == ops) { 122 auth_flavors[flavor] = NULL; 123 ret = 0; 124 } 125 spin_unlock(&rpc_authflavor_lock); 126 return ret; 127 } 128 EXPORT_SYMBOL_GPL(rpcauth_unregister); 129 130 /** 131 * rpcauth_get_pseudoflavor - check if security flavor is supported 132 * @flavor: a security flavor 133 * @info: a GSS mech OID, quality of protection, and service value 134 * 135 * Verifies that an appropriate kernel module is available or already loaded. 136 * Returns an equivalent pseudoflavor, or RPC_AUTH_MAXFLAVOR if "flavor" is 137 * not supported locally. 138 */ 139 rpc_authflavor_t 140 rpcauth_get_pseudoflavor(rpc_authflavor_t flavor, struct rpcsec_gss_info *info) 141 { 142 const struct rpc_authops *ops; 143 rpc_authflavor_t pseudoflavor; 144 145 ops = auth_flavors[flavor]; 146 if (ops == NULL) 147 request_module("rpc-auth-%u", flavor); 148 spin_lock(&rpc_authflavor_lock); 149 ops = auth_flavors[flavor]; 150 if (ops == NULL || !try_module_get(ops->owner)) { 151 spin_unlock(&rpc_authflavor_lock); 152 return RPC_AUTH_MAXFLAVOR; 153 } 154 spin_unlock(&rpc_authflavor_lock); 155 156 pseudoflavor = flavor; 157 if (ops->info2flavor != NULL) 158 pseudoflavor = ops->info2flavor(info); 159 160 module_put(ops->owner); 161 return pseudoflavor; 162 } 163 EXPORT_SYMBOL_GPL(rpcauth_get_pseudoflavor); 164 165 /** 166 * rpcauth_get_gssinfo - find GSS tuple matching a GSS pseudoflavor 167 * @pseudoflavor: GSS pseudoflavor to match 168 * @info: rpcsec_gss_info structure to fill in 169 * 170 * Returns zero and fills in "info" if pseudoflavor matches a 171 * supported mechanism. 172 */ 173 int 174 rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info) 175 { 176 rpc_authflavor_t flavor = pseudoflavor_to_flavor(pseudoflavor); 177 const struct rpc_authops *ops; 178 int result; 179 180 if (flavor >= RPC_AUTH_MAXFLAVOR) 181 return -EINVAL; 182 183 ops = auth_flavors[flavor]; 184 if (ops == NULL) 185 request_module("rpc-auth-%u", flavor); 186 spin_lock(&rpc_authflavor_lock); 187 ops = auth_flavors[flavor]; 188 if (ops == NULL || !try_module_get(ops->owner)) { 189 spin_unlock(&rpc_authflavor_lock); 190 return -ENOENT; 191 } 192 spin_unlock(&rpc_authflavor_lock); 193 194 result = -ENOENT; 195 if (ops->flavor2info != NULL) 196 result = ops->flavor2info(pseudoflavor, info); 197 198 module_put(ops->owner); 199 return result; 200 } 201 EXPORT_SYMBOL_GPL(rpcauth_get_gssinfo); 202 203 /** 204 * rpcauth_list_flavors - discover registered flavors and pseudoflavors 205 * @array: array to fill in 206 * @size: size of "array" 207 * 208 * Returns the number of array items filled in, or a negative errno. 209 * 210 * The returned array is not sorted by any policy. Callers should not 211 * rely on the order of the items in the returned array. 212 */ 213 int 214 rpcauth_list_flavors(rpc_authflavor_t *array, int size) 215 { 216 rpc_authflavor_t flavor; 217 int result = 0; 218 219 spin_lock(&rpc_authflavor_lock); 220 for (flavor = 0; flavor < RPC_AUTH_MAXFLAVOR; flavor++) { 221 const struct rpc_authops *ops = auth_flavors[flavor]; 222 rpc_authflavor_t pseudos[4]; 223 int i, len; 224 225 if (result >= size) { 226 result = -ENOMEM; 227 break; 228 } 229 230 if (ops == NULL) 231 continue; 232 if (ops->list_pseudoflavors == NULL) { 233 array[result++] = ops->au_flavor; 234 continue; 235 } 236 len = ops->list_pseudoflavors(pseudos, ARRAY_SIZE(pseudos)); 237 if (len < 0) { 238 result = len; 239 break; 240 } 241 for (i = 0; i < len; i++) { 242 if (result >= size) { 243 result = -ENOMEM; 244 break; 245 } 246 array[result++] = pseudos[i]; 247 } 248 } 249 spin_unlock(&rpc_authflavor_lock); 250 251 dprintk("RPC: %s returns %d\n", __func__, result); 252 return result; 253 } 254 EXPORT_SYMBOL_GPL(rpcauth_list_flavors); 255 256 struct rpc_auth * 257 rpcauth_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt) 258 { 259 struct rpc_auth *auth; 260 const struct rpc_authops *ops; 261 u32 flavor = pseudoflavor_to_flavor(args->pseudoflavor); 262 263 auth = ERR_PTR(-EINVAL); 264 if (flavor >= RPC_AUTH_MAXFLAVOR) 265 goto out; 266 267 if ((ops = auth_flavors[flavor]) == NULL) 268 request_module("rpc-auth-%u", flavor); 269 spin_lock(&rpc_authflavor_lock); 270 ops = auth_flavors[flavor]; 271 if (ops == NULL || !try_module_get(ops->owner)) { 272 spin_unlock(&rpc_authflavor_lock); 273 goto out; 274 } 275 spin_unlock(&rpc_authflavor_lock); 276 auth = ops->create(args, clnt); 277 module_put(ops->owner); 278 if (IS_ERR(auth)) 279 return auth; 280 if (clnt->cl_auth) 281 rpcauth_release(clnt->cl_auth); 282 clnt->cl_auth = auth; 283 284 out: 285 return auth; 286 } 287 EXPORT_SYMBOL_GPL(rpcauth_create); 288 289 void 290 rpcauth_release(struct rpc_auth *auth) 291 { 292 if (!atomic_dec_and_test(&auth->au_count)) 293 return; 294 auth->au_ops->destroy(auth); 295 } 296 297 static DEFINE_SPINLOCK(rpc_credcache_lock); 298 299 static void 300 rpcauth_unhash_cred_locked(struct rpc_cred *cred) 301 { 302 hlist_del_rcu(&cred->cr_hash); 303 smp_mb__before_atomic(); 304 clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags); 305 } 306 307 static int 308 rpcauth_unhash_cred(struct rpc_cred *cred) 309 { 310 spinlock_t *cache_lock; 311 int ret; 312 313 cache_lock = &cred->cr_auth->au_credcache->lock; 314 spin_lock(cache_lock); 315 ret = atomic_read(&cred->cr_count) == 0; 316 if (ret) 317 rpcauth_unhash_cred_locked(cred); 318 spin_unlock(cache_lock); 319 return ret; 320 } 321 322 /* 323 * Initialize RPC credential cache 324 */ 325 int 326 rpcauth_init_credcache(struct rpc_auth *auth) 327 { 328 struct rpc_cred_cache *new; 329 unsigned int hashsize; 330 331 new = kmalloc(sizeof(*new), GFP_KERNEL); 332 if (!new) 333 goto out_nocache; 334 new->hashbits = auth_hashbits; 335 hashsize = 1U << new->hashbits; 336 new->hashtable = kcalloc(hashsize, sizeof(new->hashtable[0]), GFP_KERNEL); 337 if (!new->hashtable) 338 goto out_nohashtbl; 339 spin_lock_init(&new->lock); 340 auth->au_credcache = new; 341 return 0; 342 out_nohashtbl: 343 kfree(new); 344 out_nocache: 345 return -ENOMEM; 346 } 347 EXPORT_SYMBOL_GPL(rpcauth_init_credcache); 348 349 /* 350 * Setup a credential key lifetime timeout notification 351 */ 352 int 353 rpcauth_key_timeout_notify(struct rpc_auth *auth, struct rpc_cred *cred) 354 { 355 if (!cred->cr_auth->au_ops->key_timeout) 356 return 0; 357 return cred->cr_auth->au_ops->key_timeout(auth, cred); 358 } 359 EXPORT_SYMBOL_GPL(rpcauth_key_timeout_notify); 360 361 bool 362 rpcauth_cred_key_to_expire(struct rpc_cred *cred) 363 { 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 break; 469 470 list_del_init(&cred->cr_lru); 471 number_cred_unused--; 472 freed++; 473 if (atomic_read(&cred->cr_count) != 0) 474 continue; 475 476 cache_lock = &cred->cr_auth->au_credcache->lock; 477 spin_lock(cache_lock); 478 if (atomic_read(&cred->cr_count) == 0) { 479 get_rpccred(cred); 480 list_add_tail(&cred->cr_lru, free); 481 rpcauth_unhash_cred_locked(cred); 482 } 483 spin_unlock(cache_lock); 484 } 485 return freed; 486 } 487 488 static unsigned long 489 rpcauth_cache_do_shrink(int nr_to_scan) 490 { 491 LIST_HEAD(free); 492 unsigned long freed; 493 494 spin_lock(&rpc_credcache_lock); 495 freed = rpcauth_prune_expired(&free, nr_to_scan); 496 spin_unlock(&rpc_credcache_lock); 497 rpcauth_destroy_credlist(&free); 498 499 return freed; 500 } 501 502 /* 503 * Run memory cache shrinker. 504 */ 505 static unsigned long 506 rpcauth_cache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) 507 508 { 509 if ((sc->gfp_mask & GFP_KERNEL) != GFP_KERNEL) 510 return SHRINK_STOP; 511 512 /* nothing left, don't come back */ 513 if (list_empty(&cred_unused)) 514 return SHRINK_STOP; 515 516 return rpcauth_cache_do_shrink(sc->nr_to_scan); 517 } 518 519 static unsigned long 520 rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc) 521 522 { 523 return (number_cred_unused / 100) * sysctl_vfs_cache_pressure; 524 } 525 526 static void 527 rpcauth_cache_enforce_limit(void) 528 { 529 unsigned long diff; 530 unsigned int nr_to_scan; 531 532 if (number_cred_unused <= auth_max_cred_cachesize) 533 return; 534 diff = number_cred_unused - auth_max_cred_cachesize; 535 nr_to_scan = 100; 536 if (diff < nr_to_scan) 537 nr_to_scan = diff; 538 rpcauth_cache_do_shrink(nr_to_scan); 539 } 540 541 /* 542 * Look up a process' credentials in the authentication cache 543 */ 544 struct rpc_cred * 545 rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred, 546 int flags, gfp_t gfp) 547 { 548 LIST_HEAD(free); 549 struct rpc_cred_cache *cache = auth->au_credcache; 550 struct rpc_cred *cred = NULL, 551 *entry, *new; 552 unsigned int nr; 553 554 nr = hash_long(from_kuid(&init_user_ns, acred->uid), cache->hashbits); 555 556 rcu_read_lock(); 557 hlist_for_each_entry_rcu(entry, &cache->hashtable[nr], cr_hash) { 558 if (!entry->cr_ops->crmatch(acred, entry, flags)) 559 continue; 560 if (flags & RPCAUTH_LOOKUP_RCU) { 561 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) && 562 !test_bit(RPCAUTH_CRED_NEW, &entry->cr_flags)) 563 cred = entry; 564 break; 565 } 566 spin_lock(&cache->lock); 567 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) { 568 spin_unlock(&cache->lock); 569 continue; 570 } 571 cred = get_rpccred(entry); 572 spin_unlock(&cache->lock); 573 break; 574 } 575 rcu_read_unlock(); 576 577 if (cred != NULL) 578 goto found; 579 580 if (flags & RPCAUTH_LOOKUP_RCU) 581 return ERR_PTR(-ECHILD); 582 583 new = auth->au_ops->crcreate(auth, acred, flags, gfp); 584 if (IS_ERR(new)) { 585 cred = new; 586 goto out; 587 } 588 589 spin_lock(&cache->lock); 590 hlist_for_each_entry(entry, &cache->hashtable[nr], cr_hash) { 591 if (!entry->cr_ops->crmatch(acred, entry, flags)) 592 continue; 593 cred = get_rpccred(entry); 594 break; 595 } 596 if (cred == NULL) { 597 cred = new; 598 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags); 599 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]); 600 } else 601 list_add_tail(&new->cr_lru, &free); 602 spin_unlock(&cache->lock); 603 rpcauth_cache_enforce_limit(); 604 found: 605 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 606 cred->cr_ops->cr_init != NULL && 607 !(flags & RPCAUTH_LOOKUP_NEW)) { 608 int res = cred->cr_ops->cr_init(auth, cred); 609 if (res < 0) { 610 put_rpccred(cred); 611 cred = ERR_PTR(res); 612 } 613 } 614 rpcauth_destroy_credlist(&free); 615 out: 616 return cred; 617 } 618 EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache); 619 620 struct rpc_cred * 621 rpcauth_lookupcred(struct rpc_auth *auth, int flags) 622 { 623 struct auth_cred acred; 624 struct rpc_cred *ret; 625 const struct cred *cred = current_cred(); 626 627 dprintk("RPC: looking up %s cred\n", 628 auth->au_ops->au_name); 629 630 memset(&acred, 0, sizeof(acred)); 631 acred.uid = cred->fsuid; 632 acred.gid = cred->fsgid; 633 acred.group_info = cred->group_info; 634 ret = auth->au_ops->lookup_cred(auth, &acred, flags); 635 return ret; 636 } 637 EXPORT_SYMBOL_GPL(rpcauth_lookupcred); 638 639 void 640 rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred, 641 struct rpc_auth *auth, const struct rpc_credops *ops) 642 { 643 INIT_HLIST_NODE(&cred->cr_hash); 644 INIT_LIST_HEAD(&cred->cr_lru); 645 atomic_set(&cred->cr_count, 1); 646 cred->cr_auth = auth; 647 cred->cr_ops = ops; 648 cred->cr_expire = jiffies; 649 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 650 cred->cr_magic = RPCAUTH_CRED_MAGIC; 651 #endif 652 cred->cr_uid = acred->uid; 653 } 654 EXPORT_SYMBOL_GPL(rpcauth_init_cred); 655 656 struct rpc_cred * 657 rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags) 658 { 659 dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid, 660 cred->cr_auth->au_ops->au_name, cred); 661 return get_rpccred(cred); 662 } 663 EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred); 664 665 static struct rpc_cred * 666 rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags) 667 { 668 struct rpc_auth *auth = task->tk_client->cl_auth; 669 struct auth_cred acred = { 670 .uid = GLOBAL_ROOT_UID, 671 .gid = GLOBAL_ROOT_GID, 672 }; 673 674 dprintk("RPC: %5u looking up %s cred\n", 675 task->tk_pid, task->tk_client->cl_auth->au_ops->au_name); 676 return auth->au_ops->lookup_cred(auth, &acred, lookupflags); 677 } 678 679 static struct rpc_cred * 680 rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags) 681 { 682 struct rpc_auth *auth = task->tk_client->cl_auth; 683 684 dprintk("RPC: %5u looking up %s cred\n", 685 task->tk_pid, auth->au_ops->au_name); 686 return rpcauth_lookupcred(auth, lookupflags); 687 } 688 689 static int 690 rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags) 691 { 692 struct rpc_rqst *req = task->tk_rqstp; 693 struct rpc_cred *new; 694 int lookupflags = 0; 695 696 if (flags & RPC_TASK_ASYNC) 697 lookupflags |= RPCAUTH_LOOKUP_NEW; 698 if (cred != NULL) 699 new = cred->cr_ops->crbind(task, cred, lookupflags); 700 else if (flags & RPC_TASK_ROOTCREDS) 701 new = rpcauth_bind_root_cred(task, lookupflags); 702 else 703 new = rpcauth_bind_new_cred(task, lookupflags); 704 if (IS_ERR(new)) 705 return PTR_ERR(new); 706 put_rpccred(req->rq_cred); 707 req->rq_cred = new; 708 return 0; 709 } 710 711 void 712 put_rpccred(struct rpc_cred *cred) 713 { 714 if (cred == NULL) 715 return; 716 /* Fast path for unhashed credentials */ 717 if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) { 718 if (atomic_dec_and_test(&cred->cr_count)) 719 cred->cr_ops->crdestroy(cred); 720 return; 721 } 722 723 if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock)) 724 return; 725 if (!list_empty(&cred->cr_lru)) { 726 number_cred_unused--; 727 list_del_init(&cred->cr_lru); 728 } 729 if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) { 730 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) { 731 cred->cr_expire = jiffies; 732 list_add_tail(&cred->cr_lru, &cred_unused); 733 number_cred_unused++; 734 goto out_nodestroy; 735 } 736 if (!rpcauth_unhash_cred(cred)) { 737 /* We were hashed and someone looked us up... */ 738 goto out_nodestroy; 739 } 740 } 741 spin_unlock(&rpc_credcache_lock); 742 cred->cr_ops->crdestroy(cred); 743 return; 744 out_nodestroy: 745 spin_unlock(&rpc_credcache_lock); 746 } 747 EXPORT_SYMBOL_GPL(put_rpccred); 748 749 __be32 * 750 rpcauth_marshcred(struct rpc_task *task, __be32 *p) 751 { 752 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 753 754 dprintk("RPC: %5u marshaling %s cred %p\n", 755 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 756 757 return cred->cr_ops->crmarshal(task, p); 758 } 759 760 __be32 * 761 rpcauth_checkverf(struct rpc_task *task, __be32 *p) 762 { 763 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 764 765 dprintk("RPC: %5u validating %s cred %p\n", 766 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 767 768 return cred->cr_ops->crvalidate(task, p); 769 } 770 771 static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp, 772 __be32 *data, void *obj) 773 { 774 struct xdr_stream xdr; 775 776 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data); 777 encode(rqstp, &xdr, obj); 778 } 779 780 int 781 rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp, 782 __be32 *data, void *obj) 783 { 784 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 785 786 dprintk("RPC: %5u using %s cred %p to wrap rpc data\n", 787 task->tk_pid, cred->cr_ops->cr_name, cred); 788 if (cred->cr_ops->crwrap_req) 789 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj); 790 /* By default, we encode the arguments normally. */ 791 rpcauth_wrap_req_encode(encode, rqstp, data, obj); 792 return 0; 793 } 794 795 static int 796 rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp, 797 __be32 *data, void *obj) 798 { 799 struct xdr_stream xdr; 800 801 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data); 802 return decode(rqstp, &xdr, obj); 803 } 804 805 int 806 rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp, 807 __be32 *data, void *obj) 808 { 809 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 810 811 dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n", 812 task->tk_pid, cred->cr_ops->cr_name, cred); 813 if (cred->cr_ops->crunwrap_resp) 814 return cred->cr_ops->crunwrap_resp(task, decode, rqstp, 815 data, obj); 816 /* By default, we decode the arguments normally. */ 817 return rpcauth_unwrap_req_decode(decode, rqstp, data, obj); 818 } 819 820 int 821 rpcauth_refreshcred(struct rpc_task *task) 822 { 823 struct rpc_cred *cred; 824 int err; 825 826 cred = task->tk_rqstp->rq_cred; 827 if (cred == NULL) { 828 err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags); 829 if (err < 0) 830 goto out; 831 cred = task->tk_rqstp->rq_cred; 832 } 833 dprintk("RPC: %5u refreshing %s cred %p\n", 834 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 835 836 err = cred->cr_ops->crrefresh(task); 837 out: 838 if (err < 0) 839 task->tk_status = err; 840 return err; 841 } 842 843 void 844 rpcauth_invalcred(struct rpc_task *task) 845 { 846 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 847 848 dprintk("RPC: %5u invalidating %s cred %p\n", 849 task->tk_pid, cred->cr_auth->au_ops->au_name, cred); 850 if (cred) 851 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 852 } 853 854 int 855 rpcauth_uptodatecred(struct rpc_task *task) 856 { 857 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 858 859 return cred == NULL || 860 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0; 861 } 862 863 static struct shrinker rpc_cred_shrinker = { 864 .count_objects = rpcauth_cache_shrink_count, 865 .scan_objects = rpcauth_cache_shrink_scan, 866 .seeks = DEFAULT_SEEKS, 867 }; 868 869 int __init rpcauth_init_module(void) 870 { 871 int err; 872 873 err = rpc_init_authunix(); 874 if (err < 0) 875 goto out1; 876 err = rpc_init_generic_auth(); 877 if (err < 0) 878 goto out2; 879 register_shrinker(&rpc_cred_shrinker); 880 return 0; 881 out2: 882 rpc_destroy_authunix(); 883 out1: 884 return err; 885 } 886 887 void rpcauth_remove_module(void) 888 { 889 rpc_destroy_authunix(); 890 rpc_destroy_generic_auth(); 891 unregister_shrinker(&rpc_cred_shrinker); 892 } 893