net/sunrpc/auth.c

   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 #ifdef RPC_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 = strict_strtoul(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 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 u32
  84 pseudoflavor_to_flavor(u32 flavor) {
  85         if (flavor >= RPC_AUTH_MAXFLAVOR)
  86                 return RPC_AUTH_GSS;
  87         return flavor;
  88 }
  89
  90 int
  91 rpcauth_register(const struct rpc_authops *ops)
  92 {
  93         rpc_authflavor_t flavor;
  94         int ret = -EPERM;
  95
  96         if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
  97                 return -EINVAL;
  98         spin_lock(&rpc_authflavor_lock);
  99         if (auth_flavors[flavor] == NULL) {
 100                 auth_flavors[flavor] = ops;
 101                 ret = 0;
 102         }
 103         spin_unlock(&rpc_authflavor_lock);
 104         return ret;
 105 }
 106 EXPORT_SYMBOL_GPL(rpcauth_register);
 107
 108 int
 109 rpcauth_unregister(const struct rpc_authops *ops)
 110 {
 111         rpc_authflavor_t flavor;
 112         int ret = -EPERM;
 113
 114         if ((flavor = ops->au_flavor) >= RPC_AUTH_MAXFLAVOR)
 115                 return -EINVAL;
 116         spin_lock(&rpc_authflavor_lock);
 117         if (auth_flavors[flavor] == ops) {
 118                 auth_flavors[flavor] = NULL;
 119                 ret = 0;
 120         }
 121         spin_unlock(&rpc_authflavor_lock);
 122         return ret;
 123 }
 124 EXPORT_SYMBOL_GPL(rpcauth_unregister);
 125
 126 /**
 127  * rpcauth_list_flavors - discover registered flavors and pseudoflavors
 128  * @array: array to fill in
 129  * @size: size of "array"
 130  *
 131  * Returns the number of array items filled in, or a negative errno.
 132  *
 133  * The returned array is not sorted by any policy.  Callers should not
 134  * rely on the order of the items in the returned array.
 135  */
 136 int
 137 rpcauth_list_flavors(rpc_authflavor_t *array, int size)
 138 {
 139         rpc_authflavor_t flavor;
 140         int result = 0;
 141
 142         spin_lock(&rpc_authflavor_lock);
 143         for (flavor = 0; flavor < RPC_AUTH_MAXFLAVOR; flavor++) {
 144                 const struct rpc_authops *ops = auth_flavors[flavor];
 145                 rpc_authflavor_t pseudos[4];
 146                 int i, len;
 147
 148                 if (result >= size) {
 149                         result = -ENOMEM;
 150                         break;
 151                 }
 152
 153                 if (ops == NULL)
 154                         continue;
 155                 if (ops->list_pseudoflavors == NULL) {
 156                         array[result++] = ops->au_flavor;
 157                         continue;
 158                 }
 159                 len = ops->list_pseudoflavors(pseudos, ARRAY_SIZE(pseudos));
 160                 if (len < 0) {
 161                         result = len;
 162                         break;
 163                 }
 164                 for (i = 0; i < len; i++) {
 165                         if (result >= size) {
 166                                 result = -ENOMEM;
 167                                 break;
 168                         }
 169                         array[result++] = pseudos[i];
 170                 }
 171         }
 172         spin_unlock(&rpc_authflavor_lock);
 173
 174         dprintk("RPC:       %s returns %d\n", __func__, result);
 175         return result;
 176 }
 177 EXPORT_SYMBOL_GPL(rpcauth_list_flavors);
 178
 179 struct rpc_auth *
 180 rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
 181 {
 182         struct rpc_auth         *auth;
 183         const struct rpc_authops *ops;
 184         u32                     flavor = pseudoflavor_to_flavor(pseudoflavor);
 185
 186         auth = ERR_PTR(-EINVAL);
 187         if (flavor >= RPC_AUTH_MAXFLAVOR)
 188                 goto out;
 189
 190         if ((ops = auth_flavors[flavor]) == NULL)
 191                 request_module("rpc-auth-%u", flavor);
 192         spin_lock(&rpc_authflavor_lock);
 193         ops = auth_flavors[flavor];
 194         if (ops == NULL || !try_module_get(ops->owner)) {
 195                 spin_unlock(&rpc_authflavor_lock);
 196                 goto out;
 197         }
 198         spin_unlock(&rpc_authflavor_lock);
 199         auth = ops->create(clnt, pseudoflavor);
 200         module_put(ops->owner);
 201         if (IS_ERR(auth))
 202                 return auth;
 203         if (clnt->cl_auth)
 204                 rpcauth_release(clnt->cl_auth);
 205         clnt->cl_auth = auth;
 206
 207 out:
 208         return auth;
 209 }
 210 EXPORT_SYMBOL_GPL(rpcauth_create);
 211
 212 void
 213 rpcauth_release(struct rpc_auth *auth)
 214 {
 215         if (!atomic_dec_and_test(&auth->au_count))
 216                 return;
 217         auth->au_ops->destroy(auth);
 218 }
 219
 220 static DEFINE_SPINLOCK(rpc_credcache_lock);
 221
 222 static void
 223 rpcauth_unhash_cred_locked(struct rpc_cred *cred)
 224 {
 225         hlist_del_rcu(&cred->cr_hash);
 226         smp_mb__before_clear_bit();
 227         clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
 228 }
 229
 230 static int
 231 rpcauth_unhash_cred(struct rpc_cred *cred)
 232 {
 233         spinlock_t *cache_lock;
 234         int ret;
 235
 236         cache_lock = &cred->cr_auth->au_credcache->lock;
 237         spin_lock(cache_lock);
 238         ret = atomic_read(&cred->cr_count) == 0;
 239         if (ret)
 240                 rpcauth_unhash_cred_locked(cred);
 241         spin_unlock(cache_lock);
 242         return ret;
 243 }
 244
 245 /*
 246  * Initialize RPC credential cache
 247  */
 248 int
 249 rpcauth_init_credcache(struct rpc_auth *auth)
 250 {
 251         struct rpc_cred_cache *new;
 252         unsigned int hashsize;
 253
 254         new = kmalloc(sizeof(*new), GFP_KERNEL);
 255         if (!new)
 256                 goto out_nocache;
 257         new->hashbits = auth_hashbits;
 258         hashsize = 1U << new->hashbits;
 259         new->hashtable = kcalloc(hashsize, sizeof(new->hashtable[0]), GFP_KERNEL);
 260         if (!new->hashtable)
 261                 goto out_nohashtbl;
 262         spin_lock_init(&new->lock);
 263         auth->au_credcache = new;
 264         return 0;
 265 out_nohashtbl:
 266         kfree(new);
 267 out_nocache:
 268         return -ENOMEM;
 269 }
 270 EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
 271
 272 /*
 273  * Destroy a list of credentials
 274  */
 275 static inline
 276 void rpcauth_destroy_credlist(struct list_head *head)
 277 {
 278         struct rpc_cred *cred;
 279
 280         while (!list_empty(head)) {
 281                 cred = list_entry(head->next, struct rpc_cred, cr_lru);
 282                 list_del_init(&cred->cr_lru);
 283                 put_rpccred(cred);
 284         }
 285 }
 286
 287 /*
 288  * Clear the RPC credential cache, and delete those credentials
 289  * that are not referenced.
 290  */
 291 void
 292 rpcauth_clear_credcache(struct rpc_cred_cache *cache)
 293 {
 294         LIST_HEAD(free);
 295         struct hlist_head *head;
 296         struct rpc_cred *cred;
 297         unsigned int hashsize = 1U << cache->hashbits;
 298         int             i;
 299
 300         spin_lock(&rpc_credcache_lock);
 301         spin_lock(&cache->lock);
 302         for (i = 0; i < hashsize; i++) {
 303                 head = &cache->hashtable[i];
 304                 while (!hlist_empty(head)) {
 305                         cred = hlist_entry(head->first, struct rpc_cred, cr_hash);
 306                         get_rpccred(cred);
 307                         if (!list_empty(&cred->cr_lru)) {
 308                                 list_del(&cred->cr_lru);
 309                                 number_cred_unused--;
 310                         }
 311                         list_add_tail(&cred->cr_lru, &free);
 312                         rpcauth_unhash_cred_locked(cred);
 313                 }
 314         }
 315         spin_unlock(&cache->lock);
 316         spin_unlock(&rpc_credcache_lock);
 317         rpcauth_destroy_credlist(&free);
 318 }
 319
 320 /*
 321  * Destroy the RPC credential cache
 322  */
 323 void
 324 rpcauth_destroy_credcache(struct rpc_auth *auth)
 325 {
 326         struct rpc_cred_cache *cache = auth->au_credcache;
 327
 328         if (cache) {
 329                 auth->au_credcache = NULL;
 330                 rpcauth_clear_credcache(cache);
 331                 kfree(cache->hashtable);
 332                 kfree(cache);
 333         }
 334 }
 335 EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
 336
 337
 338 #define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ)
 339
 340 /*
 341  * Remove stale credentials. Avoid sleeping inside the loop.
 342  */
 343 static int
 344 rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
 345 {
 346         spinlock_t *cache_lock;
 347         struct rpc_cred *cred, *next;
 348         unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
 349
 350         list_for_each_entry_safe(cred, next, &cred_unused, cr_lru) {
 351
 352                 if (nr_to_scan-- == 0)
 353                         break;
 354                 /*
 355                  * Enforce a 60 second garbage collection moratorium
 356                  * Note that the cred_unused list must be time-ordered.
 357                  */
 358                 if (time_in_range(cred->cr_expire, expired, jiffies) &&
 359                     test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0)
 360                         return 0;
 361
 362                 list_del_init(&cred->cr_lru);
 363                 number_cred_unused--;
 364                 if (atomic_read(&cred->cr_count) != 0)
 365                         continue;
 366
 367                 cache_lock = &cred->cr_auth->au_credcache->lock;
 368                 spin_lock(cache_lock);
 369                 if (atomic_read(&cred->cr_count) == 0) {
 370                         get_rpccred(cred);
 371                         list_add_tail(&cred->cr_lru, free);
 372                         rpcauth_unhash_cred_locked(cred);
 373                 }
 374                 spin_unlock(cache_lock);
 375         }
 376         return (number_cred_unused / 100) * sysctl_vfs_cache_pressure;
 377 }
 378
 379 /*
 380  * Run memory cache shrinker.
 381  */
 382 static int
 383 rpcauth_cache_shrinker(struct shrinker *shrink, struct shrink_control *sc)
 384 {
 385         LIST_HEAD(free);
 386         int res;
 387         int nr_to_scan = sc->nr_to_scan;
 388         gfp_t gfp_mask = sc->gfp_mask;
 389
 390         if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
 391                 return (nr_to_scan == 0) ? 0 : -1;
 392         if (list_empty(&cred_unused))
 393                 return 0;
 394         spin_lock(&rpc_credcache_lock);
 395         res = rpcauth_prune_expired(&free, nr_to_scan);
 396         spin_unlock(&rpc_credcache_lock);
 397         rpcauth_destroy_credlist(&free);
 398         return res;
 399 }
 400
 401 /*
 402  * Look up a process' credentials in the authentication cache
 403  */
 404 struct rpc_cred *
 405 rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
 406                 int flags)
 407 {
 408         LIST_HEAD(free);
 409         struct rpc_cred_cache *cache = auth->au_credcache;
 410         struct rpc_cred *cred = NULL,
 411                         *entry, *new;
 412         unsigned int nr;
 413
 414         nr = hash_long(from_kuid(&init_user_ns, acred->uid), cache->hashbits);
 415
 416         rcu_read_lock();
 417         hlist_for_each_entry_rcu(entry, &cache->hashtable[nr], cr_hash) {
 418                 if (!entry->cr_ops->crmatch(acred, entry, flags))
 419                         continue;
 420                 spin_lock(&cache->lock);
 421                 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
 422                         spin_unlock(&cache->lock);
 423                         continue;
 424                 }
 425                 cred = get_rpccred(entry);
 426                 spin_unlock(&cache->lock);
 427                 break;
 428         }
 429         rcu_read_unlock();
 430
 431         if (cred != NULL)
 432                 goto found;
 433
 434         new = auth->au_ops->crcreate(auth, acred, flags);
 435         if (IS_ERR(new)) {
 436                 cred = new;
 437                 goto out;
 438         }
 439
 440         spin_lock(&cache->lock);
 441         hlist_for_each_entry(entry, &cache->hashtable[nr], cr_hash) {
 442                 if (!entry->cr_ops->crmatch(acred, entry, flags))
 443                         continue;
 444                 cred = get_rpccred(entry);
 445                 break;
 446         }
 447         if (cred == NULL) {
 448                 cred = new;
 449                 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
 450                 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
 451         } else
 452                 list_add_tail(&new->cr_lru, &free);
 453         spin_unlock(&cache->lock);
 454 found:
 455         if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
 456             cred->cr_ops->cr_init != NULL &&
 457             !(flags & RPCAUTH_LOOKUP_NEW)) {
 458                 int res = cred->cr_ops->cr_init(auth, cred);
 459                 if (res < 0) {
 460                         put_rpccred(cred);
 461                         cred = ERR_PTR(res);
 462                 }
 463         }
 464         rpcauth_destroy_credlist(&free);
 465 out:
 466         return cred;
 467 }
 468 EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
 469
 470 struct rpc_cred *
 471 rpcauth_lookupcred(struct rpc_auth *auth, int flags)
 472 {
 473         struct auth_cred acred;
 474         struct rpc_cred *ret;
 475         const struct cred *cred = current_cred();
 476
 477         dprintk("RPC:       looking up %s cred\n",
 478                 auth->au_ops->au_name);
 479
 480         memset(&acred, 0, sizeof(acred));
 481         acred.uid = cred->fsuid;
 482         acred.gid = cred->fsgid;
 483         acred.group_info = get_group_info(((struct cred *)cred)->group_info);
 484
 485         ret = auth->au_ops->lookup_cred(auth, &acred, flags);
 486         put_group_info(acred.group_info);
 487         return ret;
 488 }
 489
 490 void
 491 rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
 492                   struct rpc_auth *auth, const struct rpc_credops *ops)
 493 {
 494         INIT_HLIST_NODE(&cred->cr_hash);
 495         INIT_LIST_HEAD(&cred->cr_lru);
 496         atomic_set(&cred->cr_count, 1);
 497         cred->cr_auth = auth;
 498         cred->cr_ops = ops;
 499         cred->cr_expire = jiffies;
 500 #ifdef RPC_DEBUG
 501         cred->cr_magic = RPCAUTH_CRED_MAGIC;
 502 #endif
 503         cred->cr_uid = acred->uid;
 504 }
 505 EXPORT_SYMBOL_GPL(rpcauth_init_cred);
 506
 507 struct rpc_cred *
 508 rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags)
 509 {
 510         dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid,
 511                         cred->cr_auth->au_ops->au_name, cred);
 512         return get_rpccred(cred);
 513 }
 514 EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred);
 515
 516 static struct rpc_cred *
 517 rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags)
 518 {
 519         struct rpc_auth *auth = task->tk_client->cl_auth;
 520         struct auth_cred acred = {
 521                 .uid = GLOBAL_ROOT_UID,
 522                 .gid = GLOBAL_ROOT_GID,
 523         };
 524
 525         dprintk("RPC: %5u looking up %s cred\n",
 526                 task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
 527         return auth->au_ops->lookup_cred(auth, &acred, lookupflags);
 528 }
 529
 530 static struct rpc_cred *
 531 rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags)
 532 {
 533         struct rpc_auth *auth = task->tk_client->cl_auth;
 534
 535         dprintk("RPC: %5u looking up %s cred\n",
 536                 task->tk_pid, auth->au_ops->au_name);
 537         return rpcauth_lookupcred(auth, lookupflags);
 538 }
 539
 540 static int
 541 rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags)
 542 {
 543         struct rpc_rqst *req = task->tk_rqstp;
 544         struct rpc_cred *new;
 545         int lookupflags = 0;
 546
 547         if (flags & RPC_TASK_ASYNC)
 548                 lookupflags |= RPCAUTH_LOOKUP_NEW;
 549         if (cred != NULL)
 550                 new = cred->cr_ops->crbind(task, cred, lookupflags);
 551         else if (flags & RPC_TASK_ROOTCREDS)
 552                 new = rpcauth_bind_root_cred(task, lookupflags);
 553         else
 554                 new = rpcauth_bind_new_cred(task, lookupflags);
 555         if (IS_ERR(new))
 556                 return PTR_ERR(new);
 557         if (req->rq_cred != NULL)
 558                 put_rpccred(req->rq_cred);
 559         req->rq_cred = new;
 560         return 0;
 561 }
 562
 563 void
 564 put_rpccred(struct rpc_cred *cred)
 565 {
 566         /* Fast path for unhashed credentials */
 567         if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) {
 568                 if (atomic_dec_and_test(&cred->cr_count))
 569                         cred->cr_ops->crdestroy(cred);
 570                 return;
 571         }
 572
 573         if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
 574                 return;
 575         if (!list_empty(&cred->cr_lru)) {
 576                 number_cred_unused--;
 577                 list_del_init(&cred->cr_lru);
 578         }
 579         if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
 580                 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) {
 581                         cred->cr_expire = jiffies;
 582                         list_add_tail(&cred->cr_lru, &cred_unused);
 583                         number_cred_unused++;
 584                         goto out_nodestroy;
 585                 }
 586                 if (!rpcauth_unhash_cred(cred)) {
 587                         /* We were hashed and someone looked us up... */
 588                         goto out_nodestroy;
 589                 }
 590         }
 591         spin_unlock(&rpc_credcache_lock);
 592         cred->cr_ops->crdestroy(cred);
 593         return;
 594 out_nodestroy:
 595         spin_unlock(&rpc_credcache_lock);
 596 }
 597 EXPORT_SYMBOL_GPL(put_rpccred);
 598
 599 __be32 *
 600 rpcauth_marshcred(struct rpc_task *task, __be32 *p)
 601 {
 602         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 603
 604         dprintk("RPC: %5u marshaling %s cred %p\n",
 605                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 606
 607         return cred->cr_ops->crmarshal(task, p);
 608 }
 609
 610 __be32 *
 611 rpcauth_checkverf(struct rpc_task *task, __be32 *p)
 612 {
 613         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 614
 615         dprintk("RPC: %5u validating %s cred %p\n",
 616                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 617
 618         return cred->cr_ops->crvalidate(task, p);
 619 }
 620
 621 static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
 622                                    __be32 *data, void *obj)
 623 {
 624         struct xdr_stream xdr;
 625
 626         xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data);
 627         encode(rqstp, &xdr, obj);
 628 }
 629
 630 int
 631 rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp,
 632                 __be32 *data, void *obj)
 633 {
 634         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 635
 636         dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
 637                         task->tk_pid, cred->cr_ops->cr_name, cred);
 638         if (cred->cr_ops->crwrap_req)
 639                 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
 640         /* By default, we encode the arguments normally. */
 641         rpcauth_wrap_req_encode(encode, rqstp, data, obj);
 642         return 0;
 643 }
 644
 645 static int
 646 rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
 647                           __be32 *data, void *obj)
 648 {
 649         struct xdr_stream xdr;
 650
 651         xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data);
 652         return decode(rqstp, &xdr, obj);
 653 }
 654
 655 int
 656 rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp,
 657                 __be32 *data, void *obj)
 658 {
 659         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 660
 661         dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
 662                         task->tk_pid, cred->cr_ops->cr_name, cred);
 663         if (cred->cr_ops->crunwrap_resp)
 664                 return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
 665                                                    data, obj);
 666         /* By default, we decode the arguments normally. */
 667         return rpcauth_unwrap_req_decode(decode, rqstp, data, obj);
 668 }
 669
 670 int
 671 rpcauth_refreshcred(struct rpc_task *task)
 672 {
 673         struct rpc_cred *cred;
 674         int err;
 675
 676         cred = task->tk_rqstp->rq_cred;
 677         if (cred == NULL) {
 678                 err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags);
 679                 if (err < 0)
 680                         goto out;
 681                 cred = task->tk_rqstp->rq_cred;
 682         }
 683         dprintk("RPC: %5u refreshing %s cred %p\n",
 684                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 685
 686         err = cred->cr_ops->crrefresh(task);
 687 out:
 688         if (err < 0)
 689                 task->tk_status = err;
 690         return err;
 691 }
 692
 693 void
 694 rpcauth_invalcred(struct rpc_task *task)
 695 {
 696         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 697
 698         dprintk("RPC: %5u invalidating %s cred %p\n",
 699                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 700         if (cred)
 701                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 702 }
 703
 704 int
 705 rpcauth_uptodatecred(struct rpc_task *task)
 706 {
 707         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 708
 709         return cred == NULL ||
 710                 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
 711 }
 712
 713 static struct shrinker rpc_cred_shrinker = {
 714         .shrink = rpcauth_cache_shrinker,
 715         .seeks = DEFAULT_SEEKS,
 716 };
 717
 718 int __init rpcauth_init_module(void)
 719 {
 720         int err;
 721
 722         err = rpc_init_authunix();
 723         if (err < 0)
 724                 goto out1;
 725         err = rpc_init_generic_auth();
 726         if (err < 0)
 727                 goto out2;
 728         register_shrinker(&rpc_cred_shrinker);
 729         return 0;
 730 out2:
 731         rpc_destroy_authunix();
 732 out1:
 733         return err;
 734 }
 735
 736 void rpcauth_remove_module(void)
 737 {
 738         rpc_destroy_authunix();
 739         rpc_destroy_generic_auth();
 740         unregister_shrinker(&rpc_cred_shrinker);
 741 }