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 hlist_node *pos;
 411         struct rpc_cred *cred = NULL,
 412                         *entry, *new;
 413         unsigned int nr;
 414
 415         nr = hash_long(acred->uid, cache->hashbits);
 416
 417         rcu_read_lock();
 418         hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) {
 419                 if (!entry->cr_ops->crmatch(acred, entry, flags))
 420                         continue;
 421                 spin_lock(&cache->lock);
 422                 if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
 423                         spin_unlock(&cache->lock);
 424                         continue;
 425                 }
 426                 cred = get_rpccred(entry);
 427                 spin_unlock(&cache->lock);
 428                 break;
 429         }
 430         rcu_read_unlock();
 431
 432         if (cred != NULL)
 433                 goto found;
 434
 435         new = auth->au_ops->crcreate(auth, acred, flags);
 436         if (IS_ERR(new)) {
 437                 cred = new;
 438                 goto out;
 439         }
 440
 441         spin_lock(&cache->lock);
 442         hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) {
 443                 if (!entry->cr_ops->crmatch(acred, entry, flags))
 444                         continue;
 445                 cred = get_rpccred(entry);
 446                 break;
 447         }
 448         if (cred == NULL) {
 449                 cred = new;
 450                 set_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
 451                 hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
 452         } else
 453                 list_add_tail(&new->cr_lru, &free);
 454         spin_unlock(&cache->lock);
 455 found:
 456         if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
 457             cred->cr_ops->cr_init != NULL &&
 458             !(flags & RPCAUTH_LOOKUP_NEW)) {
 459                 int res = cred->cr_ops->cr_init(auth, cred);
 460                 if (res < 0) {
 461                         put_rpccred(cred);
 462                         cred = ERR_PTR(res);
 463                 }
 464         }
 465         rpcauth_destroy_credlist(&free);
 466 out:
 467         return cred;
 468 }
 469 EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
 470
 471 struct rpc_cred *
 472 rpcauth_lookupcred(struct rpc_auth *auth, int flags)
 473 {
 474         struct auth_cred acred;
 475         struct rpc_cred *ret;
 476         const struct cred *cred = current_cred();
 477
 478         dprintk("RPC:       looking up %s cred\n",
 479                 auth->au_ops->au_name);
 480
 481         memset(&acred, 0, sizeof(acred));
 482         acred.uid = cred->fsuid;
 483         acred.gid = cred->fsgid;
 484         acred.group_info = get_group_info(((struct cred *)cred)->group_info);
 485
 486         ret = auth->au_ops->lookup_cred(auth, &acred, flags);
 487         put_group_info(acred.group_info);
 488         return ret;
 489 }
 490
 491 void
 492 rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
 493                   struct rpc_auth *auth, const struct rpc_credops *ops)
 494 {
 495         INIT_HLIST_NODE(&cred->cr_hash);
 496         INIT_LIST_HEAD(&cred->cr_lru);
 497         atomic_set(&cred->cr_count, 1);
 498         cred->cr_auth = auth;
 499         cred->cr_ops = ops;
 500         cred->cr_expire = jiffies;
 501 #ifdef RPC_DEBUG
 502         cred->cr_magic = RPCAUTH_CRED_MAGIC;
 503 #endif
 504         cred->cr_uid = acred->uid;
 505 }
 506 EXPORT_SYMBOL_GPL(rpcauth_init_cred);
 507
 508 struct rpc_cred *
 509 rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags)
 510 {
 511         dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid,
 512                         cred->cr_auth->au_ops->au_name, cred);
 513         return get_rpccred(cred);
 514 }
 515 EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred);
 516
 517 static struct rpc_cred *
 518 rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags)
 519 {
 520         struct rpc_auth *auth = task->tk_client->cl_auth;
 521         struct auth_cred acred = {
 522                 .uid = 0,
 523                 .gid = 0,
 524         };
 525
 526         dprintk("RPC: %5u looking up %s cred\n",
 527                 task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
 528         return auth->au_ops->lookup_cred(auth, &acred, lookupflags);
 529 }
 530
 531 static struct rpc_cred *
 532 rpcauth_bind_new_cred(struct rpc_task *task, int lookupflags)
 533 {
 534         struct rpc_auth *auth = task->tk_client->cl_auth;
 535
 536         dprintk("RPC: %5u looking up %s cred\n",
 537                 task->tk_pid, auth->au_ops->au_name);
 538         return rpcauth_lookupcred(auth, lookupflags);
 539 }
 540
 541 static int
 542 rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags)
 543 {
 544         struct rpc_rqst *req = task->tk_rqstp;
 545         struct rpc_cred *new;
 546         int lookupflags = 0;
 547
 548         if (flags & RPC_TASK_ASYNC)
 549                 lookupflags |= RPCAUTH_LOOKUP_NEW;
 550         if (cred != NULL)
 551                 new = cred->cr_ops->crbind(task, cred, lookupflags);
 552         else if (flags & RPC_TASK_ROOTCREDS)
 553                 new = rpcauth_bind_root_cred(task, lookupflags);
 554         else
 555                 new = rpcauth_bind_new_cred(task, lookupflags);
 556         if (IS_ERR(new))
 557                 return PTR_ERR(new);
 558         if (req->rq_cred != NULL)
 559                 put_rpccred(req->rq_cred);
 560         req->rq_cred = new;
 561         return 0;
 562 }
 563
 564 void
 565 put_rpccred(struct rpc_cred *cred)
 566 {
 567         /* Fast path for unhashed credentials */
 568         if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) {
 569                 if (atomic_dec_and_test(&cred->cr_count))
 570                         cred->cr_ops->crdestroy(cred);
 571                 return;
 572         }
 573
 574         if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
 575                 return;
 576         if (!list_empty(&cred->cr_lru)) {
 577                 number_cred_unused--;
 578                 list_del_init(&cred->cr_lru);
 579         }
 580         if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
 581                 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0) {
 582                         cred->cr_expire = jiffies;
 583                         list_add_tail(&cred->cr_lru, &cred_unused);
 584                         number_cred_unused++;
 585                         goto out_nodestroy;
 586                 }
 587                 if (!rpcauth_unhash_cred(cred)) {
 588                         /* We were hashed and someone looked us up... */
 589                         goto out_nodestroy;
 590                 }
 591         }
 592         spin_unlock(&rpc_credcache_lock);
 593         cred->cr_ops->crdestroy(cred);
 594         return;
 595 out_nodestroy:
 596         spin_unlock(&rpc_credcache_lock);
 597 }
 598 EXPORT_SYMBOL_GPL(put_rpccred);
 599
 600 __be32 *
 601 rpcauth_marshcred(struct rpc_task *task, __be32 *p)
 602 {
 603         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 604
 605         dprintk("RPC: %5u marshaling %s cred %p\n",
 606                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 607
 608         return cred->cr_ops->crmarshal(task, p);
 609 }
 610
 611 __be32 *
 612 rpcauth_checkverf(struct rpc_task *task, __be32 *p)
 613 {
 614         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 615
 616         dprintk("RPC: %5u validating %s cred %p\n",
 617                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 618
 619         return cred->cr_ops->crvalidate(task, p);
 620 }
 621
 622 static void rpcauth_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
 623                                    __be32 *data, void *obj)
 624 {
 625         struct xdr_stream xdr;
 626
 627         xdr_init_encode(&xdr, &rqstp->rq_snd_buf, data);
 628         encode(rqstp, &xdr, obj);
 629 }
 630
 631 int
 632 rpcauth_wrap_req(struct rpc_task *task, kxdreproc_t encode, void *rqstp,
 633                 __be32 *data, void *obj)
 634 {
 635         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 636
 637         dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
 638                         task->tk_pid, cred->cr_ops->cr_name, cred);
 639         if (cred->cr_ops->crwrap_req)
 640                 return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
 641         /* By default, we encode the arguments normally. */
 642         rpcauth_wrap_req_encode(encode, rqstp, data, obj);
 643         return 0;
 644 }
 645
 646 static int
 647 rpcauth_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
 648                           __be32 *data, void *obj)
 649 {
 650         struct xdr_stream xdr;
 651
 652         xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, data);
 653         return decode(rqstp, &xdr, obj);
 654 }
 655
 656 int
 657 rpcauth_unwrap_resp(struct rpc_task *task, kxdrdproc_t decode, void *rqstp,
 658                 __be32 *data, void *obj)
 659 {
 660         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 661
 662         dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
 663                         task->tk_pid, cred->cr_ops->cr_name, cred);
 664         if (cred->cr_ops->crunwrap_resp)
 665                 return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
 666                                                    data, obj);
 667         /* By default, we decode the arguments normally. */
 668         return rpcauth_unwrap_req_decode(decode, rqstp, data, obj);
 669 }
 670
 671 int
 672 rpcauth_refreshcred(struct rpc_task *task)
 673 {
 674         struct rpc_cred *cred;
 675         int err;
 676
 677         cred = task->tk_rqstp->rq_cred;
 678         if (cred == NULL) {
 679                 err = rpcauth_bindcred(task, task->tk_msg.rpc_cred, task->tk_flags);
 680                 if (err < 0)
 681                         goto out;
 682                 cred = task->tk_rqstp->rq_cred;
 683         }
 684         dprintk("RPC: %5u refreshing %s cred %p\n",
 685                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 686
 687         err = cred->cr_ops->crrefresh(task);
 688 out:
 689         if (err < 0)
 690                 task->tk_status = err;
 691         return err;
 692 }
 693
 694 void
 695 rpcauth_invalcred(struct rpc_task *task)
 696 {
 697         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 698
 699         dprintk("RPC: %5u invalidating %s cred %p\n",
 700                 task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 701         if (cred)
 702                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 703 }
 704
 705 int
 706 rpcauth_uptodatecred(struct rpc_task *task)
 707 {
 708         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 709
 710         return cred == NULL ||
 711                 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
 712 }
 713
 714 static struct shrinker rpc_cred_shrinker = {
 715         .shrink = rpcauth_cache_shrinker,
 716         .seeks = DEFAULT_SEEKS,
 717 };
 718
 719 int __init rpcauth_init_module(void)
 720 {
 721         int err;
 722
 723         err = rpc_init_authunix();
 724         if (err < 0)
 725                 goto out1;
 726         err = rpc_init_generic_auth();
 727         if (err < 0)
 728                 goto out2;
 729         register_shrinker(&rpc_cred_shrinker);
 730         return 0;
 731 out2:
 732         rpc_destroy_authunix();
 733 out1:
 734         return err;
 735 }
 736
 737 void rpcauth_remove_module(void)
 738 {
 739         rpc_destroy_authunix();
 740         rpc_destroy_generic_auth();
 741         unregister_shrinker(&rpc_cred_shrinker);
 742 }