net/sunrpc/auth_gss/auth_gss.c

   1 /*
   2  * linux/net/sunrpc/auth_gss/auth_gss.c
   3  *
   4  * RPCSEC_GSS client authentication.
   5  *
   6  *  Copyright (c) 2000 The Regents of the University of Michigan.
   7  *  All rights reserved.
   8  *
   9  *  Dug Song       <dugsong@monkey.org>
  10  *  Andy Adamson   <andros@umich.edu>
  11  *
  12  *  Redistribution and use in source and binary forms, with or without
  13  *  modification, are permitted provided that the following conditions
  14  *  are met:
  15  *
  16  *  1. Redistributions of source code must retain the above copyright
  17  *     notice, this list of conditions and the following disclaimer.
  18  *  2. Redistributions in binary form must reproduce the above copyright
  19  *     notice, this list of conditions and the following disclaimer in the
  20  *     documentation and/or other materials provided with the distribution.
  21  *  3. Neither the name of the University nor the names of its
  22  *     contributors may be used to endorse or promote products derived
  23  *     from this software without specific prior written permission.
  24  *
  25  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  26  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  27  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  28  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  29  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  32  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  33  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  34  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  35  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38
  39 #include <linux/module.h>
  40 #include <linux/init.h>
  41 #include <linux/types.h>
  42 #include <linux/slab.h>
  43 #include <linux/sched.h>
  44 #include <linux/pagemap.h>
  45 #include <linux/sunrpc/clnt.h>
  46 #include <linux/sunrpc/auth.h>
  47 #include <linux/sunrpc/auth_gss.h>
  48 #include <linux/sunrpc/svcauth_gss.h>
  49 #include <linux/sunrpc/gss_err.h>
  50 #include <linux/workqueue.h>
  51 #include <linux/sunrpc/rpc_pipe_fs.h>
  52 #include <linux/sunrpc/gss_api.h>
  53 #include <asm/uaccess.h>
  54 #include <linux/hashtable.h>
  55
  56 #include "../netns.h"
  57
  58 static const struct rpc_authops authgss_ops;
  59
  60 static const struct rpc_credops gss_credops;
  61 static const struct rpc_credops gss_nullops;
  62
  63 #define GSS_RETRY_EXPIRED 5
  64 static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED;
  65
  66 #define GSS_KEY_EXPIRE_TIMEO 240
  67 static unsigned int gss_key_expire_timeo = GSS_KEY_EXPIRE_TIMEO;
  68
  69 #ifdef RPC_DEBUG
  70 # define RPCDBG_FACILITY        RPCDBG_AUTH
  71 #endif
  72
  73 #define GSS_CRED_SLACK          (RPC_MAX_AUTH_SIZE * 2)
  74 /* length of a krb5 verifier (48), plus data added before arguments when
  75  * using integrity (two 4-byte integers): */
  76 #define GSS_VERF_SLACK          100
  77
  78 static DEFINE_HASHTABLE(gss_auth_hash_table, 4);
  79 static DEFINE_SPINLOCK(gss_auth_hash_lock);
  80
  81 struct gss_pipe {
  82         struct rpc_pipe_dir_object pdo;
  83         struct rpc_pipe *pipe;
  84         struct rpc_clnt *clnt;
  85         const char *name;
  86         struct kref kref;
  87 };
  88
  89 struct gss_auth {
  90         struct kref kref;
  91         struct hlist_node hash;
  92         struct rpc_auth rpc_auth;
  93         struct gss_api_mech *mech;
  94         enum rpc_gss_svc service;
  95         struct rpc_clnt *client;
  96         struct net *net;
  97         /*
  98          * There are two upcall pipes; dentry[1], named "gssd", is used
  99          * for the new text-based upcall; dentry[0] is named after the
 100          * mechanism (for example, "krb5") and exists for
 101          * backwards-compatibility with older gssd's.
 102          */
 103         struct gss_pipe *gss_pipe[2];
 104         const char *target_name;
 105 };
 106
 107 /* pipe_version >= 0 if and only if someone has a pipe open. */
 108 static DEFINE_SPINLOCK(pipe_version_lock);
 109 static struct rpc_wait_queue pipe_version_rpc_waitqueue;
 110 static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue);
 111
 112 static void gss_free_ctx(struct gss_cl_ctx *);
 113 static const struct rpc_pipe_ops gss_upcall_ops_v0;
 114 static const struct rpc_pipe_ops gss_upcall_ops_v1;
 115
 116 static inline struct gss_cl_ctx *
 117 gss_get_ctx(struct gss_cl_ctx *ctx)
 118 {
 119         atomic_inc(&ctx->count);
 120         return ctx;
 121 }
 122
 123 static inline void
 124 gss_put_ctx(struct gss_cl_ctx *ctx)
 125 {
 126         if (atomic_dec_and_test(&ctx->count))
 127                 gss_free_ctx(ctx);
 128 }
 129
 130 /* gss_cred_set_ctx:
 131  * called by gss_upcall_callback and gss_create_upcall in order
 132  * to set the gss context. The actual exchange of an old context
 133  * and a new one is protected by the pipe->lock.
 134  */
 135 static void
 136 gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
 137 {
 138         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
 139
 140         if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags))
 141                 return;
 142         gss_get_ctx(ctx);
 143         rcu_assign_pointer(gss_cred->gc_ctx, ctx);
 144         set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 145         smp_mb__before_clear_bit();
 146         clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags);
 147 }
 148
 149 static const void *
 150 simple_get_bytes(const void *p, const void *end, void *res, size_t len)
 151 {
 152         const void *q = (const void *)((const char *)p + len);
 153         if (unlikely(q > end || q < p))
 154                 return ERR_PTR(-EFAULT);
 155         memcpy(res, p, len);
 156         return q;
 157 }
 158
 159 static inline const void *
 160 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest)
 161 {
 162         const void *q;
 163         unsigned int len;
 164
 165         p = simple_get_bytes(p, end, &len, sizeof(len));
 166         if (IS_ERR(p))
 167                 return p;
 168         q = (const void *)((const char *)p + len);
 169         if (unlikely(q > end || q < p))
 170                 return ERR_PTR(-EFAULT);
 171         dest->data = kmemdup(p, len, GFP_NOFS);
 172         if (unlikely(dest->data == NULL))
 173                 return ERR_PTR(-ENOMEM);
 174         dest->len = len;
 175         return q;
 176 }
 177
 178 static struct gss_cl_ctx *
 179 gss_cred_get_ctx(struct rpc_cred *cred)
 180 {
 181         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
 182         struct gss_cl_ctx *ctx = NULL;
 183
 184         rcu_read_lock();
 185         if (gss_cred->gc_ctx)
 186                 ctx = gss_get_ctx(gss_cred->gc_ctx);
 187         rcu_read_unlock();
 188         return ctx;
 189 }
 190
 191 static struct gss_cl_ctx *
 192 gss_alloc_context(void)
 193 {
 194         struct gss_cl_ctx *ctx;
 195
 196         ctx = kzalloc(sizeof(*ctx), GFP_NOFS);
 197         if (ctx != NULL) {
 198                 ctx->gc_proc = RPC_GSS_PROC_DATA;
 199                 ctx->gc_seq = 1;        /* NetApp 6.4R1 doesn't accept seq. no. 0 */
 200                 spin_lock_init(&ctx->gc_seq_lock);
 201                 atomic_set(&ctx->count,1);
 202         }
 203         return ctx;
 204 }
 205
 206 #define GSSD_MIN_TIMEOUT (60 * 60)
 207 static const void *
 208 gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm)
 209 {
 210         const void *q;
 211         unsigned int seclen;
 212         unsigned int timeout;
 213         unsigned long now = jiffies;
 214         u32 window_size;
 215         int ret;
 216
 217         /* First unsigned int gives the remaining lifetime in seconds of the
 218          * credential - e.g. the remaining TGT lifetime for Kerberos or
 219          * the -t value passed to GSSD.
 220          */
 221         p = simple_get_bytes(p, end, &timeout, sizeof(timeout));
 222         if (IS_ERR(p))
 223                 goto err;
 224         if (timeout == 0)
 225                 timeout = GSSD_MIN_TIMEOUT;
 226         ctx->gc_expiry = now + ((unsigned long)timeout * HZ);
 227         /* Sequence number window. Determines the maximum number of
 228          * simultaneous requests
 229          */
 230         p = simple_get_bytes(p, end, &window_size, sizeof(window_size));
 231         if (IS_ERR(p))
 232                 goto err;
 233         ctx->gc_win = window_size;
 234         /* gssd signals an error by passing ctx->gc_win = 0: */
 235         if (ctx->gc_win == 0) {
 236                 /*
 237                  * in which case, p points to an error code. Anything other
 238                  * than -EKEYEXPIRED gets converted to -EACCES.
 239                  */
 240                 p = simple_get_bytes(p, end, &ret, sizeof(ret));
 241                 if (!IS_ERR(p))
 242                         p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) :
 243                                                     ERR_PTR(-EACCES);
 244                 goto err;
 245         }
 246         /* copy the opaque wire context */
 247         p = simple_get_netobj(p, end, &ctx->gc_wire_ctx);
 248         if (IS_ERR(p))
 249                 goto err;
 250         /* import the opaque security context */
 251         p  = simple_get_bytes(p, end, &seclen, sizeof(seclen));
 252         if (IS_ERR(p))
 253                 goto err;
 254         q = (const void *)((const char *)p + seclen);
 255         if (unlikely(q > end || q < p)) {
 256                 p = ERR_PTR(-EFAULT);
 257                 goto err;
 258         }
 259         ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, NULL, GFP_NOFS);
 260         if (ret < 0) {
 261                 p = ERR_PTR(ret);
 262                 goto err;
 263         }
 264         dprintk("RPC:       %s Success. gc_expiry %lu now %lu timeout %u\n",
 265                 __func__, ctx->gc_expiry, now, timeout);
 266         return q;
 267 err:
 268         dprintk("RPC:       %s returns error %ld\n", __func__, -PTR_ERR(p));
 269         return p;
 270 }
 271
 272 #define UPCALL_BUF_LEN 128
 273
 274 struct gss_upcall_msg {
 275         atomic_t count;
 276         kuid_t  uid;
 277         struct rpc_pipe_msg msg;
 278         struct list_head list;
 279         struct gss_auth *auth;
 280         struct rpc_pipe *pipe;
 281         struct rpc_wait_queue rpc_waitqueue;
 282         wait_queue_head_t waitqueue;
 283         struct gss_cl_ctx *ctx;
 284         char databuf[UPCALL_BUF_LEN];
 285 };
 286
 287 static int get_pipe_version(struct net *net)
 288 {
 289         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 290         int ret;
 291
 292         spin_lock(&pipe_version_lock);
 293         if (sn->pipe_version >= 0) {
 294                 atomic_inc(&sn->pipe_users);
 295                 ret = sn->pipe_version;
 296         } else
 297                 ret = -EAGAIN;
 298         spin_unlock(&pipe_version_lock);
 299         return ret;
 300 }
 301
 302 static void put_pipe_version(struct net *net)
 303 {
 304         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 305
 306         if (atomic_dec_and_lock(&sn->pipe_users, &pipe_version_lock)) {
 307                 sn->pipe_version = -1;
 308                 spin_unlock(&pipe_version_lock);
 309         }
 310 }
 311
 312 static void
 313 gss_release_msg(struct gss_upcall_msg *gss_msg)
 314 {
 315         struct net *net = gss_msg->auth->net;
 316         if (!atomic_dec_and_test(&gss_msg->count))
 317                 return;
 318         put_pipe_version(net);
 319         BUG_ON(!list_empty(&gss_msg->list));
 320         if (gss_msg->ctx != NULL)
 321                 gss_put_ctx(gss_msg->ctx);
 322         rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue);
 323         kfree(gss_msg);
 324 }
 325
 326 static struct gss_upcall_msg *
 327 __gss_find_upcall(struct rpc_pipe *pipe, kuid_t uid)
 328 {
 329         struct gss_upcall_msg *pos;
 330         list_for_each_entry(pos, &pipe->in_downcall, list) {
 331                 if (!uid_eq(pos->uid, uid))
 332                         continue;
 333                 atomic_inc(&pos->count);
 334                 dprintk("RPC:       %s found msg %p\n", __func__, pos);
 335                 return pos;
 336         }
 337         dprintk("RPC:       %s found nothing\n", __func__);
 338         return NULL;
 339 }
 340
 341 /* Try to add an upcall to the pipefs queue.
 342  * If an upcall owned by our uid already exists, then we return a reference
 343  * to that upcall instead of adding the new upcall.
 344  */
 345 static inline struct gss_upcall_msg *
 346 gss_add_msg(struct gss_upcall_msg *gss_msg)
 347 {
 348         struct rpc_pipe *pipe = gss_msg->pipe;
 349         struct gss_upcall_msg *old;
 350
 351         spin_lock(&pipe->lock);
 352         old = __gss_find_upcall(pipe, gss_msg->uid);
 353         if (old == NULL) {
 354                 atomic_inc(&gss_msg->count);
 355                 list_add(&gss_msg->list, &pipe->in_downcall);
 356         } else
 357                 gss_msg = old;
 358         spin_unlock(&pipe->lock);
 359         return gss_msg;
 360 }
 361
 362 static void
 363 __gss_unhash_msg(struct gss_upcall_msg *gss_msg)
 364 {
 365         list_del_init(&gss_msg->list);
 366         rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
 367         wake_up_all(&gss_msg->waitqueue);
 368         atomic_dec(&gss_msg->count);
 369 }
 370
 371 static void
 372 gss_unhash_msg(struct gss_upcall_msg *gss_msg)
 373 {
 374         struct rpc_pipe *pipe = gss_msg->pipe;
 375
 376         if (list_empty(&gss_msg->list))
 377                 return;
 378         spin_lock(&pipe->lock);
 379         if (!list_empty(&gss_msg->list))
 380                 __gss_unhash_msg(gss_msg);
 381         spin_unlock(&pipe->lock);
 382 }
 383
 384 static void
 385 gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg)
 386 {
 387         switch (gss_msg->msg.errno) {
 388         case 0:
 389                 if (gss_msg->ctx == NULL)
 390                         break;
 391                 clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
 392                 gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx);
 393                 break;
 394         case -EKEYEXPIRED:
 395                 set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
 396         }
 397         gss_cred->gc_upcall_timestamp = jiffies;
 398         gss_cred->gc_upcall = NULL;
 399         rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
 400 }
 401
 402 static void
 403 gss_upcall_callback(struct rpc_task *task)
 404 {
 405         struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred,
 406                         struct gss_cred, gc_base);
 407         struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall;
 408         struct rpc_pipe *pipe = gss_msg->pipe;
 409
 410         spin_lock(&pipe->lock);
 411         gss_handle_downcall_result(gss_cred, gss_msg);
 412         spin_unlock(&pipe->lock);
 413         task->tk_status = gss_msg->msg.errno;
 414         gss_release_msg(gss_msg);
 415 }
 416
 417 static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
 418 {
 419         uid_t uid = from_kuid(&init_user_ns, gss_msg->uid);
 420         memcpy(gss_msg->databuf, &uid, sizeof(uid));
 421         gss_msg->msg.data = gss_msg->databuf;
 422         gss_msg->msg.len = sizeof(uid);
 423
 424         BUILD_BUG_ON(sizeof(uid) > sizeof(gss_msg->databuf));
 425 }
 426
 427 static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
 428                                 const char *service_name,
 429                                 const char *target_name)
 430 {
 431         struct gss_api_mech *mech = gss_msg->auth->mech;
 432         char *p = gss_msg->databuf;
 433         size_t buflen = sizeof(gss_msg->databuf);
 434         int len;
 435
 436         len = scnprintf(p, buflen, "mech=%s uid=%d ", mech->gm_name,
 437                         from_kuid(&init_user_ns, gss_msg->uid));
 438         buflen -= len;
 439         p += len;
 440         gss_msg->msg.len = len;
 441         if (target_name) {
 442                 len = scnprintf(p, buflen, "target=%s ", target_name);
 443                 buflen -= len;
 444                 p += len;
 445                 gss_msg->msg.len += len;
 446         }
 447         if (service_name != NULL) {
 448                 len = scnprintf(p, buflen, "service=%s ", service_name);
 449                 buflen -= len;
 450                 p += len;
 451                 gss_msg->msg.len += len;
 452         }
 453         if (mech->gm_upcall_enctypes) {
 454                 len = scnprintf(p, buflen, "enctypes=%s ",
 455                                 mech->gm_upcall_enctypes);
 456                 buflen -= len;
 457                 p += len;
 458                 gss_msg->msg.len += len;
 459         }
 460         len = scnprintf(p, buflen, "\n");
 461         if (len == 0)
 462                 goto out_overflow;
 463         gss_msg->msg.len += len;
 464
 465         gss_msg->msg.data = gss_msg->databuf;
 466         return 0;
 467 out_overflow:
 468         WARN_ON_ONCE(1);
 469         return -ENOMEM;
 470 }
 471
 472 static struct gss_upcall_msg *
 473 gss_alloc_msg(struct gss_auth *gss_auth,
 474                 kuid_t uid, const char *service_name)
 475 {
 476         struct gss_upcall_msg *gss_msg;
 477         int vers;
 478         int err = -ENOMEM;
 479
 480         gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
 481         if (gss_msg == NULL)
 482                 goto err;
 483         vers = get_pipe_version(gss_auth->net);
 484         err = vers;
 485         if (err < 0)
 486                 goto err_free_msg;
 487         gss_msg->pipe = gss_auth->gss_pipe[vers]->pipe;
 488         INIT_LIST_HEAD(&gss_msg->list);
 489         rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
 490         init_waitqueue_head(&gss_msg->waitqueue);
 491         atomic_set(&gss_msg->count, 1);
 492         gss_msg->uid = uid;
 493         gss_msg->auth = gss_auth;
 494         switch (vers) {
 495         case 0:
 496                 gss_encode_v0_msg(gss_msg);
 497                 break;
 498         default:
 499                 err = gss_encode_v1_msg(gss_msg, service_name, gss_auth->target_name);
 500                 if (err)
 501                         goto err_free_msg;
 502         };
 503         return gss_msg;
 504 err_free_msg:
 505         kfree(gss_msg);
 506 err:
 507         return ERR_PTR(err);
 508 }
 509
 510 static struct gss_upcall_msg *
 511 gss_setup_upcall(struct gss_auth *gss_auth, struct rpc_cred *cred)
 512 {
 513         struct gss_cred *gss_cred = container_of(cred,
 514                         struct gss_cred, gc_base);
 515         struct gss_upcall_msg *gss_new, *gss_msg;
 516         kuid_t uid = cred->cr_uid;
 517
 518         gss_new = gss_alloc_msg(gss_auth, uid, gss_cred->gc_principal);
 519         if (IS_ERR(gss_new))
 520                 return gss_new;
 521         gss_msg = gss_add_msg(gss_new);
 522         if (gss_msg == gss_new) {
 523                 int res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg);
 524                 if (res) {
 525                         gss_unhash_msg(gss_new);
 526                         gss_msg = ERR_PTR(res);
 527                 }
 528         } else
 529                 gss_release_msg(gss_new);
 530         return gss_msg;
 531 }
 532
 533 static void warn_gssd(void)
 534 {
 535         static unsigned long ratelimit;
 536         unsigned long now = jiffies;
 537
 538         if (time_after(now, ratelimit)) {
 539                 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n"
 540                                 "Please check user daemon is running.\n");
 541                 ratelimit = now + 15*HZ;
 542         }
 543 }
 544
 545 static inline int
 546 gss_refresh_upcall(struct rpc_task *task)
 547 {
 548         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
 549         struct gss_auth *gss_auth = container_of(cred->cr_auth,
 550                         struct gss_auth, rpc_auth);
 551         struct gss_cred *gss_cred = container_of(cred,
 552                         struct gss_cred, gc_base);
 553         struct gss_upcall_msg *gss_msg;
 554         struct rpc_pipe *pipe;
 555         int err = 0;
 556
 557         dprintk("RPC: %5u %s for uid %u\n",
 558                 task->tk_pid, __func__, from_kuid(&init_user_ns, cred->cr_uid));
 559         gss_msg = gss_setup_upcall(gss_auth, cred);
 560         if (PTR_ERR(gss_msg) == -EAGAIN) {
 561                 /* XXX: warning on the first, under the assumption we
 562                  * shouldn't normally hit this case on a refresh. */
 563                 warn_gssd();
 564                 task->tk_timeout = 15*HZ;
 565                 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL);
 566                 return -EAGAIN;
 567         }
 568         if (IS_ERR(gss_msg)) {
 569                 err = PTR_ERR(gss_msg);
 570                 goto out;
 571         }
 572         pipe = gss_msg->pipe;
 573         spin_lock(&pipe->lock);
 574         if (gss_cred->gc_upcall != NULL)
 575                 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL);
 576         else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) {
 577                 task->tk_timeout = 0;
 578                 gss_cred->gc_upcall = gss_msg;
 579                 /* gss_upcall_callback will release the reference to gss_upcall_msg */
 580                 atomic_inc(&gss_msg->count);
 581                 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback);
 582         } else {
 583                 gss_handle_downcall_result(gss_cred, gss_msg);
 584                 err = gss_msg->msg.errno;
 585         }
 586         spin_unlock(&pipe->lock);
 587         gss_release_msg(gss_msg);
 588 out:
 589         dprintk("RPC: %5u %s for uid %u result %d\n",
 590                 task->tk_pid, __func__,
 591                 from_kuid(&init_user_ns, cred->cr_uid), err);
 592         return err;
 593 }
 594
 595 static inline int
 596 gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
 597 {
 598         struct net *net = gss_auth->net;
 599         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 600         struct rpc_pipe *pipe;
 601         struct rpc_cred *cred = &gss_cred->gc_base;
 602         struct gss_upcall_msg *gss_msg;
 603         unsigned long timeout;
 604         DEFINE_WAIT(wait);
 605         int err;
 606
 607         dprintk("RPC:       %s for uid %u\n",
 608                 __func__, from_kuid(&init_user_ns, cred->cr_uid));
 609 retry:
 610         err = 0;
 611         /* Default timeout is 15s unless we know that gssd is not running */
 612         timeout = 15 * HZ;
 613         if (!sn->gssd_running)
 614                 timeout = HZ >> 2;
 615         gss_msg = gss_setup_upcall(gss_auth, cred);
 616         if (PTR_ERR(gss_msg) == -EAGAIN) {
 617                 err = wait_event_interruptible_timeout(pipe_version_waitqueue,
 618                                 sn->pipe_version >= 0, timeout);
 619                 if (sn->pipe_version < 0) {
 620                         if (err == 0)
 621                                 sn->gssd_running = 0;
 622                         warn_gssd();
 623                         err = -EACCES;
 624                 }
 625                 if (err < 0)
 626                         goto out;
 627                 goto retry;
 628         }
 629         if (IS_ERR(gss_msg)) {
 630                 err = PTR_ERR(gss_msg);
 631                 goto out;
 632         }
 633         pipe = gss_msg->pipe;
 634         for (;;) {
 635                 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE);
 636                 spin_lock(&pipe->lock);
 637                 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) {
 638                         break;
 639                 }
 640                 spin_unlock(&pipe->lock);
 641                 if (fatal_signal_pending(current)) {
 642                         err = -ERESTARTSYS;
 643                         goto out_intr;
 644                 }
 645                 schedule();
 646         }
 647         if (gss_msg->ctx)
 648                 gss_cred_set_ctx(cred, gss_msg->ctx);
 649         else
 650                 err = gss_msg->msg.errno;
 651         spin_unlock(&pipe->lock);
 652 out_intr:
 653         finish_wait(&gss_msg->waitqueue, &wait);
 654         gss_release_msg(gss_msg);
 655 out:
 656         dprintk("RPC:       %s for uid %u result %d\n",
 657                 __func__, from_kuid(&init_user_ns, cred->cr_uid), err);
 658         return err;
 659 }
 660
 661 #define MSG_BUF_MAXSIZE 1024
 662
 663 static ssize_t
 664 gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 665 {
 666         const void *p, *end;
 667         void *buf;
 668         struct gss_upcall_msg *gss_msg;
 669         struct rpc_pipe *pipe = RPC_I(file_inode(filp))->pipe;
 670         struct gss_cl_ctx *ctx;
 671         uid_t id;
 672         kuid_t uid;
 673         ssize_t err = -EFBIG;
 674
 675         if (mlen > MSG_BUF_MAXSIZE)
 676                 goto out;
 677         err = -ENOMEM;
 678         buf = kmalloc(mlen, GFP_NOFS);
 679         if (!buf)
 680                 goto out;
 681
 682         err = -EFAULT;
 683         if (copy_from_user(buf, src, mlen))
 684                 goto err;
 685
 686         end = (const void *)((char *)buf + mlen);
 687         p = simple_get_bytes(buf, end, &id, sizeof(id));
 688         if (IS_ERR(p)) {
 689                 err = PTR_ERR(p);
 690                 goto err;
 691         }
 692
 693         uid = make_kuid(&init_user_ns, id);
 694         if (!uid_valid(uid)) {
 695                 err = -EINVAL;
 696                 goto err;
 697         }
 698
 699         err = -ENOMEM;
 700         ctx = gss_alloc_context();
 701         if (ctx == NULL)
 702                 goto err;
 703
 704         err = -ENOENT;
 705         /* Find a matching upcall */
 706         spin_lock(&pipe->lock);
 707         gss_msg = __gss_find_upcall(pipe, uid);
 708         if (gss_msg == NULL) {
 709                 spin_unlock(&pipe->lock);
 710                 goto err_put_ctx;
 711         }
 712         list_del_init(&gss_msg->list);
 713         spin_unlock(&pipe->lock);
 714
 715         p = gss_fill_context(p, end, ctx, gss_msg->auth->mech);
 716         if (IS_ERR(p)) {
 717                 err = PTR_ERR(p);
 718                 switch (err) {
 719                 case -EACCES:
 720                 case -EKEYEXPIRED:
 721                         gss_msg->msg.errno = err;
 722                         err = mlen;
 723                         break;
 724                 case -EFAULT:
 725                 case -ENOMEM:
 726                 case -EINVAL:
 727                 case -ENOSYS:
 728                         gss_msg->msg.errno = -EAGAIN;
 729                         break;
 730                 default:
 731                         printk(KERN_CRIT "%s: bad return from "
 732                                 "gss_fill_context: %zd\n", __func__, err);
 733                         BUG();
 734                 }
 735                 goto err_release_msg;
 736         }
 737         gss_msg->ctx = gss_get_ctx(ctx);
 738         err = mlen;
 739
 740 err_release_msg:
 741         spin_lock(&pipe->lock);
 742         __gss_unhash_msg(gss_msg);
 743         spin_unlock(&pipe->lock);
 744         gss_release_msg(gss_msg);
 745 err_put_ctx:
 746         gss_put_ctx(ctx);
 747 err:
 748         kfree(buf);
 749 out:
 750         dprintk("RPC:       %s returning %Zd\n", __func__, err);
 751         return err;
 752 }
 753
 754 static int gss_pipe_open(struct inode *inode, int new_version)
 755 {
 756         struct net *net = inode->i_sb->s_fs_info;
 757         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 758         int ret = 0;
 759
 760         spin_lock(&pipe_version_lock);
 761         if (sn->pipe_version < 0) {
 762                 /* First open of any gss pipe determines the version: */
 763                 sn->pipe_version = new_version;
 764                 rpc_wake_up(&pipe_version_rpc_waitqueue);
 765                 wake_up(&pipe_version_waitqueue);
 766         } else if (sn->pipe_version != new_version) {
 767                 /* Trying to open a pipe of a different version */
 768                 ret = -EBUSY;
 769                 goto out;
 770         }
 771         atomic_inc(&sn->pipe_users);
 772 out:
 773         spin_unlock(&pipe_version_lock);
 774         return ret;
 775
 776 }
 777
 778 static int gss_pipe_open_v0(struct inode *inode)
 779 {
 780         return gss_pipe_open(inode, 0);
 781 }
 782
 783 static int gss_pipe_open_v1(struct inode *inode)
 784 {
 785         return gss_pipe_open(inode, 1);
 786 }
 787
 788 static void
 789 gss_pipe_release(struct inode *inode)
 790 {
 791         struct net *net = inode->i_sb->s_fs_info;
 792         struct rpc_pipe *pipe = RPC_I(inode)->pipe;
 793         struct gss_upcall_msg *gss_msg;
 794
 795 restart:
 796         spin_lock(&pipe->lock);
 797         list_for_each_entry(gss_msg, &pipe->in_downcall, list) {
 798
 799                 if (!list_empty(&gss_msg->msg.list))
 800                         continue;
 801                 gss_msg->msg.errno = -EPIPE;
 802                 atomic_inc(&gss_msg->count);
 803                 __gss_unhash_msg(gss_msg);
 804                 spin_unlock(&pipe->lock);
 805                 gss_release_msg(gss_msg);
 806                 goto restart;
 807         }
 808         spin_unlock(&pipe->lock);
 809
 810         put_pipe_version(net);
 811 }
 812
 813 static void
 814 gss_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 815 {
 816         struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg);
 817
 818         if (msg->errno < 0) {
 819                 dprintk("RPC:       %s releasing msg %p\n",
 820                         __func__, gss_msg);
 821                 atomic_inc(&gss_msg->count);
 822                 gss_unhash_msg(gss_msg);
 823                 if (msg->errno == -ETIMEDOUT)
 824                         warn_gssd();
 825                 gss_release_msg(gss_msg);
 826         }
 827 }
 828
 829 static void gss_pipe_dentry_destroy(struct dentry *dir,
 830                 struct rpc_pipe_dir_object *pdo)
 831 {
 832         struct gss_pipe *gss_pipe = pdo->pdo_data;
 833         struct rpc_pipe *pipe = gss_pipe->pipe;
 834
 835         if (pipe->dentry != NULL) {
 836                 rpc_unlink(pipe->dentry);
 837                 pipe->dentry = NULL;
 838         }
 839 }
 840
 841 static int gss_pipe_dentry_create(struct dentry *dir,
 842                 struct rpc_pipe_dir_object *pdo)
 843 {
 844         struct gss_pipe *p = pdo->pdo_data;
 845         struct dentry *dentry;
 846
 847         dentry = rpc_mkpipe_dentry(dir, p->name, p->clnt, p->pipe);
 848         if (IS_ERR(dentry))
 849                 return PTR_ERR(dentry);
 850         p->pipe->dentry = dentry;
 851         return 0;
 852 }
 853
 854 static const struct rpc_pipe_dir_object_ops gss_pipe_dir_object_ops = {
 855         .create = gss_pipe_dentry_create,
 856         .destroy = gss_pipe_dentry_destroy,
 857 };
 858
 859 static struct gss_pipe *gss_pipe_alloc(struct rpc_clnt *clnt,
 860                 const char *name,
 861                 const struct rpc_pipe_ops *upcall_ops)
 862 {
 863         struct gss_pipe *p;
 864         int err = -ENOMEM;
 865
 866         p = kmalloc(sizeof(*p), GFP_KERNEL);
 867         if (p == NULL)
 868                 goto err;
 869         p->pipe = rpc_mkpipe_data(upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
 870         if (IS_ERR(p->pipe)) {
 871                 err = PTR_ERR(p->pipe);
 872                 goto err_free_gss_pipe;
 873         }
 874         p->name = name;
 875         p->clnt = clnt;
 876         kref_init(&p->kref);
 877         rpc_init_pipe_dir_object(&p->pdo,
 878                         &gss_pipe_dir_object_ops,
 879                         p);
 880         return p;
 881 err_free_gss_pipe:
 882         kfree(p);
 883 err:
 884         return ERR_PTR(err);
 885 }
 886
 887 struct gss_alloc_pdo {
 888         struct rpc_clnt *clnt;
 889         const char *name;
 890         const struct rpc_pipe_ops *upcall_ops;
 891 };
 892
 893 static int gss_pipe_match_pdo(struct rpc_pipe_dir_object *pdo, void *data)
 894 {
 895         struct gss_pipe *gss_pipe;
 896         struct gss_alloc_pdo *args = data;
 897
 898         if (pdo->pdo_ops != &gss_pipe_dir_object_ops)
 899                 return 0;
 900         gss_pipe = container_of(pdo, struct gss_pipe, pdo);
 901         if (strcmp(gss_pipe->name, args->name) != 0)
 902                 return 0;
 903         if (!kref_get_unless_zero(&gss_pipe->kref))
 904                 return 0;
 905         return 1;
 906 }
 907
 908 static struct rpc_pipe_dir_object *gss_pipe_alloc_pdo(void *data)
 909 {
 910         struct gss_pipe *gss_pipe;
 911         struct gss_alloc_pdo *args = data;
 912
 913         gss_pipe = gss_pipe_alloc(args->clnt, args->name, args->upcall_ops);
 914         if (!IS_ERR(gss_pipe))
 915                 return &gss_pipe->pdo;
 916         return NULL;
 917 }
 918
 919 static struct gss_pipe *gss_pipe_get(struct rpc_clnt *clnt,
 920                 const char *name,
 921                 const struct rpc_pipe_ops *upcall_ops)
 922 {
 923         struct net *net = rpc_net_ns(clnt);
 924         struct rpc_pipe_dir_object *pdo;
 925         struct gss_alloc_pdo args = {
 926                 .clnt = clnt,
 927                 .name = name,
 928                 .upcall_ops = upcall_ops,
 929         };
 930
 931         pdo = rpc_find_or_alloc_pipe_dir_object(net,
 932                         &clnt->cl_pipedir_objects,
 933                         gss_pipe_match_pdo,
 934                         gss_pipe_alloc_pdo,
 935                         &args);
 936         if (pdo != NULL)
 937                 return container_of(pdo, struct gss_pipe, pdo);
 938         return ERR_PTR(-ENOMEM);
 939 }
 940
 941 static void __gss_pipe_free(struct gss_pipe *p)
 942 {
 943         struct rpc_clnt *clnt = p->clnt;
 944         struct net *net = rpc_net_ns(clnt);
 945
 946         rpc_remove_pipe_dir_object(net,
 947                         &clnt->cl_pipedir_objects,
 948                         &p->pdo);
 949         rpc_destroy_pipe_data(p->pipe);
 950         kfree(p);
 951 }
 952
 953 static void __gss_pipe_release(struct kref *kref)
 954 {
 955         struct gss_pipe *p = container_of(kref, struct gss_pipe, kref);
 956
 957         __gss_pipe_free(p);
 958 }
 959
 960 static void gss_pipe_free(struct gss_pipe *p)
 961 {
 962         if (p != NULL)
 963                 kref_put(&p->kref, __gss_pipe_release);
 964 }
 965
 966 /*
 967  * NOTE: we have the opportunity to use different
 968  * parameters based on the input flavor (which must be a pseudoflavor)
 969  */
 970 static struct gss_auth *
 971 gss_create_new(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
 972 {
 973         rpc_authflavor_t flavor = args->pseudoflavor;
 974         struct gss_auth *gss_auth;
 975         struct gss_pipe *gss_pipe;
 976         struct rpc_auth * auth;
 977         int err = -ENOMEM; /* XXX? */
 978
 979         dprintk("RPC:       creating GSS authenticator for client %p\n", clnt);
 980
 981         if (!try_module_get(THIS_MODULE))
 982                 return ERR_PTR(err);
 983         if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL)))
 984                 goto out_dec;
 985         INIT_HLIST_NODE(&gss_auth->hash);
 986         gss_auth->target_name = NULL;
 987         if (args->target_name) {
 988                 gss_auth->target_name = kstrdup(args->target_name, GFP_KERNEL);
 989                 if (gss_auth->target_name == NULL)
 990                         goto err_free;
 991         }
 992         gss_auth->client = clnt;
 993         gss_auth->net = get_net(rpc_net_ns(clnt));
 994         err = -EINVAL;
 995         gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor);
 996         if (!gss_auth->mech) {
 997                 dprintk("RPC:       Pseudoflavor %d not found!\n", flavor);
 998                 goto err_put_net;
 999         }
1000         gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
1001         if (gss_auth->service == 0)
1002                 goto err_put_mech;
1003         auth = &gss_auth->rpc_auth;
1004         auth->au_cslack = GSS_CRED_SLACK >> 2;
1005         auth->au_rslack = GSS_VERF_SLACK >> 2;
1006         auth->au_ops = &authgss_ops;
1007         auth->au_flavor = flavor;
1008         atomic_set(&auth->au_count, 1);
1009         kref_init(&gss_auth->kref);
1010
1011         err = rpcauth_init_credcache(auth);
1012         if (err)
1013                 goto err_put_mech;
1014         /*
1015          * Note: if we created the old pipe first, then someone who
1016          * examined the directory at the right moment might conclude
1017          * that we supported only the old pipe.  So we instead create
1018          * the new pipe first.
1019          */
1020         gss_pipe = gss_pipe_get(clnt, "gssd", &gss_upcall_ops_v1);
1021         if (IS_ERR(gss_pipe)) {
1022                 err = PTR_ERR(gss_pipe);
1023                 goto err_destroy_credcache;
1024         }
1025         gss_auth->gss_pipe[1] = gss_pipe;
1026
1027         gss_pipe = gss_pipe_get(clnt, gss_auth->mech->gm_name,
1028                         &gss_upcall_ops_v0);
1029         if (IS_ERR(gss_pipe)) {
1030                 err = PTR_ERR(gss_pipe);
1031                 goto err_destroy_pipe_1;
1032         }
1033         gss_auth->gss_pipe[0] = gss_pipe;
1034
1035         return gss_auth;
1036 err_destroy_pipe_1:
1037         gss_pipe_free(gss_auth->gss_pipe[1]);
1038 err_destroy_credcache:
1039         rpcauth_destroy_credcache(auth);
1040 err_put_mech:
1041         gss_mech_put(gss_auth->mech);
1042 err_put_net:
1043         put_net(gss_auth->net);
1044 err_free:
1045         kfree(gss_auth->target_name);
1046         kfree(gss_auth);
1047 out_dec:
1048         module_put(THIS_MODULE);
1049         return ERR_PTR(err);
1050 }
1051
1052 static void
1053 gss_free(struct gss_auth *gss_auth)
1054 {
1055         gss_pipe_free(gss_auth->gss_pipe[0]);
1056         gss_pipe_free(gss_auth->gss_pipe[1]);
1057         gss_mech_put(gss_auth->mech);
1058         put_net(gss_auth->net);
1059         kfree(gss_auth->target_name);
1060
1061         kfree(gss_auth);
1062         module_put(THIS_MODULE);
1063 }
1064
1065 static void
1066 gss_free_callback(struct kref *kref)
1067 {
1068         struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref);
1069
1070         gss_free(gss_auth);
1071 }
1072
1073 static void
1074 gss_destroy(struct rpc_auth *auth)
1075 {
1076         struct gss_auth *gss_auth = container_of(auth,
1077                         struct gss_auth, rpc_auth);
1078
1079         dprintk("RPC:       destroying GSS authenticator %p flavor %d\n",
1080                         auth, auth->au_flavor);
1081
1082         if (hash_hashed(&gss_auth->hash)) {
1083                 spin_lock(&gss_auth_hash_lock);
1084                 hash_del(&gss_auth->hash);
1085                 spin_unlock(&gss_auth_hash_lock);
1086         }
1087
1088         gss_pipe_free(gss_auth->gss_pipe[0]);
1089         gss_auth->gss_pipe[0] = NULL;
1090         gss_pipe_free(gss_auth->gss_pipe[1]);
1091         gss_auth->gss_pipe[1] = NULL;
1092         rpcauth_destroy_credcache(auth);
1093
1094         kref_put(&gss_auth->kref, gss_free_callback);
1095 }
1096
1097 /*
1098  * Auths may be shared between rpc clients that were cloned from a
1099  * common client with the same xprt, if they also share the flavor and
1100  * target_name.
1101  *
1102  * The auth is looked up from the oldest parent sharing the same
1103  * cl_xprt, and the auth itself references only that common parent
1104  * (which is guaranteed to last as long as any of its descendants).
1105  */
1106 static struct gss_auth *
1107 gss_auth_find_or_add_hashed(struct rpc_auth_create_args *args,
1108                 struct rpc_clnt *clnt,
1109                 struct gss_auth *new)
1110 {
1111         struct gss_auth *gss_auth;
1112         unsigned long hashval = (unsigned long)clnt;
1113
1114         spin_lock(&gss_auth_hash_lock);
1115         hash_for_each_possible(gss_auth_hash_table,
1116                         gss_auth,
1117                         hash,
1118                         hashval) {
1119                 if (gss_auth->client != clnt)
1120                         continue;
1121                 if (gss_auth->rpc_auth.au_flavor != args->pseudoflavor)
1122                         continue;
1123                 if (gss_auth->target_name != args->target_name) {
1124                         if (gss_auth->target_name == NULL)
1125                                 continue;
1126                         if (args->target_name == NULL)
1127                                 continue;
1128                         if (strcmp(gss_auth->target_name, args->target_name))
1129                                 continue;
1130                 }
1131                 if (!atomic_inc_not_zero(&gss_auth->rpc_auth.au_count))
1132                         continue;
1133                 goto out;
1134         }
1135         if (new)
1136                 hash_add(gss_auth_hash_table, &new->hash, hashval);
1137         gss_auth = new;
1138 out:
1139         spin_unlock(&gss_auth_hash_lock);
1140         return gss_auth;
1141 }
1142
1143 static struct gss_auth *
1144 gss_create_hashed(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
1145 {
1146         struct gss_auth *gss_auth;
1147         struct gss_auth *new;
1148
1149         gss_auth = gss_auth_find_or_add_hashed(args, clnt, NULL);
1150         if (gss_auth != NULL)
1151                 goto out;
1152         new = gss_create_new(args, clnt);
1153         if (IS_ERR(new))
1154                 return new;
1155         gss_auth = gss_auth_find_or_add_hashed(args, clnt, new);
1156         if (gss_auth != new)
1157                 gss_destroy(&new->rpc_auth);
1158 out:
1159         return gss_auth;
1160 }
1161
1162 static struct rpc_auth *
1163 gss_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
1164 {
1165         struct gss_auth *gss_auth;
1166         struct rpc_xprt *xprt = rcu_access_pointer(clnt->cl_xprt);
1167
1168         while (clnt != clnt->cl_parent) {
1169                 struct rpc_clnt *parent = clnt->cl_parent;
1170                 /* Find the original parent for this transport */
1171                 if (rcu_access_pointer(parent->cl_xprt) != xprt)
1172                         break;
1173                 clnt = parent;
1174         }
1175
1176         gss_auth = gss_create_hashed(args, clnt);
1177         if (IS_ERR(gss_auth))
1178                 return ERR_CAST(gss_auth);
1179         return &gss_auth->rpc_auth;
1180 }
1181
1182 /*
1183  * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call
1184  * to the server with the GSS control procedure field set to
1185  * RPC_GSS_PROC_DESTROY. This should normally cause the server to release
1186  * all RPCSEC_GSS state associated with that context.
1187  */
1188 static int
1189 gss_destroying_context(struct rpc_cred *cred)
1190 {
1191         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
1192         struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
1193         struct rpc_task *task;
1194
1195         if (gss_cred->gc_ctx == NULL ||
1196             test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0)
1197                 return 0;
1198
1199         gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY;
1200         cred->cr_ops = &gss_nullops;
1201
1202         /* Take a reference to ensure the cred will be destroyed either
1203          * by the RPC call or by the put_rpccred() below */
1204         get_rpccred(cred);
1205
1206         task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT);
1207         if (!IS_ERR(task))
1208                 rpc_put_task(task);
1209
1210         put_rpccred(cred);
1211         return 1;
1212 }
1213
1214 /* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure
1215  * to create a new cred or context, so they check that things have been
1216  * allocated before freeing them. */
1217 static void
1218 gss_do_free_ctx(struct gss_cl_ctx *ctx)
1219 {
1220         dprintk("RPC:       %s\n", __func__);
1221
1222         gss_delete_sec_context(&ctx->gc_gss_ctx);
1223         kfree(ctx->gc_wire_ctx.data);
1224         kfree(ctx);
1225 }
1226
1227 static void
1228 gss_free_ctx_callback(struct rcu_head *head)
1229 {
1230         struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu);
1231         gss_do_free_ctx(ctx);
1232 }
1233
1234 static void
1235 gss_free_ctx(struct gss_cl_ctx *ctx)
1236 {
1237         call_rcu(&ctx->gc_rcu, gss_free_ctx_callback);
1238 }
1239
1240 static void
1241 gss_free_cred(struct gss_cred *gss_cred)
1242 {
1243         dprintk("RPC:       %s cred=%p\n", __func__, gss_cred);
1244         kfree(gss_cred);
1245 }
1246
1247 static void
1248 gss_free_cred_callback(struct rcu_head *head)
1249 {
1250         struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu);
1251         gss_free_cred(gss_cred);
1252 }
1253
1254 static void
1255 gss_destroy_nullcred(struct rpc_cred *cred)
1256 {
1257         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
1258         struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
1259         struct gss_cl_ctx *ctx = gss_cred->gc_ctx;
1260
1261         RCU_INIT_POINTER(gss_cred->gc_ctx, NULL);
1262         call_rcu(&cred->cr_rcu, gss_free_cred_callback);
1263         if (ctx)
1264                 gss_put_ctx(ctx);
1265         kref_put(&gss_auth->kref, gss_free_callback);
1266 }
1267
1268 static void
1269 gss_destroy_cred(struct rpc_cred *cred)
1270 {
1271
1272         if (gss_destroying_context(cred))
1273                 return;
1274         gss_destroy_nullcred(cred);
1275 }
1276
1277 /*
1278  * Lookup RPCSEC_GSS cred for the current process
1279  */
1280 static struct rpc_cred *
1281 gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
1282 {
1283         return rpcauth_lookup_credcache(auth, acred, flags);
1284 }
1285
1286 static struct rpc_cred *
1287 gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
1288 {
1289         struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
1290         struct gss_cred *cred = NULL;
1291         int err = -ENOMEM;
1292
1293         dprintk("RPC:       %s for uid %d, flavor %d\n",
1294                 __func__, from_kuid(&init_user_ns, acred->uid),
1295                 auth->au_flavor);
1296
1297         if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS)))
1298                 goto out_err;
1299
1300         rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops);
1301         /*
1302          * Note: in order to force a call to call_refresh(), we deliberately
1303          * fail to flag the credential as RPCAUTH_CRED_UPTODATE.
1304          */
1305         cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW;
1306         cred->gc_service = gss_auth->service;
1307         cred->gc_principal = NULL;
1308         if (acred->machine_cred)
1309                 cred->gc_principal = acred->principal;
1310         kref_get(&gss_auth->kref);
1311         return &cred->gc_base;
1312
1313 out_err:
1314         dprintk("RPC:       %s failed with error %d\n", __func__, err);
1315         return ERR_PTR(err);
1316 }
1317
1318 static int
1319 gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred)
1320 {
1321         struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
1322         struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base);
1323         int err;
1324
1325         do {
1326                 err = gss_create_upcall(gss_auth, gss_cred);
1327         } while (err == -EAGAIN);
1328         return err;
1329 }
1330
1331 /*
1332  * Returns -EACCES if GSS context is NULL or will expire within the
1333  * timeout (miliseconds)
1334  */
1335 static int
1336 gss_key_timeout(struct rpc_cred *rc)
1337 {
1338         struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
1339         unsigned long now = jiffies;
1340         unsigned long expire;
1341
1342         if (gss_cred->gc_ctx == NULL)
1343                 return -EACCES;
1344
1345         expire = gss_cred->gc_ctx->gc_expiry - (gss_key_expire_timeo * HZ);
1346
1347         if (time_after(now, expire))
1348                 return -EACCES;
1349         return 0;
1350 }
1351
1352 static int
1353 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags)
1354 {
1355         struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
1356         int ret;
1357
1358         if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags))
1359                 goto out;
1360         /* Don't match with creds that have expired. */
1361         if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry))
1362                 return 0;
1363         if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags))
1364                 return 0;
1365 out:
1366         if (acred->principal != NULL) {
1367                 if (gss_cred->gc_principal == NULL)
1368                         return 0;
1369                 ret = strcmp(acred->principal, gss_cred->gc_principal) == 0;
1370                 goto check_expire;
1371         }
1372         if (gss_cred->gc_principal != NULL)
1373                 return 0;
1374         ret = uid_eq(rc->cr_uid, acred->uid);
1375
1376 check_expire:
1377         if (ret == 0)
1378                 return ret;
1379
1380         /* Notify acred users of GSS context expiration timeout */
1381         if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags) &&
1382             (gss_key_timeout(rc) != 0)) {
1383                 /* test will now be done from generic cred */
1384                 test_and_clear_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
1385                 /* tell NFS layer that key will expire soon */
1386                 set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
1387         }
1388         return ret;
1389 }
1390
1391 /*
1392 * Marshal credentials.
1393 * Maybe we should keep a cached credential for performance reasons.
1394 */
1395 static __be32 *
1396 gss_marshal(struct rpc_task *task, __be32 *p)
1397 {
1398         struct rpc_rqst *req = task->tk_rqstp;
1399         struct rpc_cred *cred = req->rq_cred;
1400         struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1401                                                  gc_base);
1402         struct gss_cl_ctx       *ctx = gss_cred_get_ctx(cred);
1403         __be32          *cred_len;
1404         u32             maj_stat = 0;
1405         struct xdr_netobj mic;
1406         struct kvec     iov;
1407         struct xdr_buf  verf_buf;
1408
1409         dprintk("RPC: %5u %s\n", task->tk_pid, __func__);
1410
1411         *p++ = htonl(RPC_AUTH_GSS);
1412         cred_len = p++;
1413
1414         spin_lock(&ctx->gc_seq_lock);
1415         req->rq_seqno = ctx->gc_seq++;
1416         spin_unlock(&ctx->gc_seq_lock);
1417
1418         *p++ = htonl((u32) RPC_GSS_VERSION);
1419         *p++ = htonl((u32) ctx->gc_proc);
1420         *p++ = htonl((u32) req->rq_seqno);
1421         *p++ = htonl((u32) gss_cred->gc_service);
1422         p = xdr_encode_netobj(p, &ctx->gc_wire_ctx);
1423         *cred_len = htonl((p - (cred_len + 1)) << 2);
1424
1425         /* We compute the checksum for the verifier over the xdr-encoded bytes
1426          * starting with the xid and ending at the end of the credential: */
1427         iov.iov_base = xprt_skip_transport_header(req->rq_xprt,
1428                                         req->rq_snd_buf.head[0].iov_base);
1429         iov.iov_len = (u8 *)p - (u8 *)iov.iov_base;
1430         xdr_buf_from_iov(&iov, &verf_buf);
1431
1432         /* set verifier flavor*/
1433         *p++ = htonl(RPC_AUTH_GSS);
1434
1435         mic.data = (u8 *)(p + 1);
1436         maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
1437         if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
1438                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1439         } else if (maj_stat != 0) {
1440                 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat);
1441                 goto out_put_ctx;
1442         }
1443         p = xdr_encode_opaque(p, NULL, mic.len);
1444         gss_put_ctx(ctx);
1445         return p;
1446 out_put_ctx:
1447         gss_put_ctx(ctx);
1448         return NULL;
1449 }
1450
1451 static int gss_renew_cred(struct rpc_task *task)
1452 {
1453         struct rpc_cred *oldcred = task->tk_rqstp->rq_cred;
1454         struct gss_cred *gss_cred = container_of(oldcred,
1455                                                  struct gss_cred,
1456                                                  gc_base);
1457         struct rpc_auth *auth = oldcred->cr_auth;
1458         struct auth_cred acred = {
1459                 .uid = oldcred->cr_uid,
1460                 .principal = gss_cred->gc_principal,
1461                 .machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0),
1462         };
1463         struct rpc_cred *new;
1464
1465         new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW);
1466         if (IS_ERR(new))
1467                 return PTR_ERR(new);
1468         task->tk_rqstp->rq_cred = new;
1469         put_rpccred(oldcred);
1470         return 0;
1471 }
1472
1473 static int gss_cred_is_negative_entry(struct rpc_cred *cred)
1474 {
1475         if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) {
1476                 unsigned long now = jiffies;
1477                 unsigned long begin, expire;
1478                 struct gss_cred *gss_cred;
1479
1480                 gss_cred = container_of(cred, struct gss_cred, gc_base);
1481                 begin = gss_cred->gc_upcall_timestamp;
1482                 expire = begin + gss_expired_cred_retry_delay * HZ;
1483
1484                 if (time_in_range_open(now, begin, expire))
1485                         return 1;
1486         }
1487         return 0;
1488 }
1489
1490 /*
1491 * Refresh credentials. XXX - finish
1492 */
1493 static int
1494 gss_refresh(struct rpc_task *task)
1495 {
1496         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1497         int ret = 0;
1498
1499         if (gss_cred_is_negative_entry(cred))
1500                 return -EKEYEXPIRED;
1501
1502         if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
1503                         !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) {
1504                 ret = gss_renew_cred(task);
1505                 if (ret < 0)
1506                         goto out;
1507                 cred = task->tk_rqstp->rq_cred;
1508         }
1509
1510         if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags))
1511                 ret = gss_refresh_upcall(task);
1512 out:
1513         return ret;
1514 }
1515
1516 /* Dummy refresh routine: used only when destroying the context */
1517 static int
1518 gss_refresh_null(struct rpc_task *task)
1519 {
1520         return 0;
1521 }
1522
1523 static __be32 *
1524 gss_validate(struct rpc_task *task, __be32 *p)
1525 {
1526         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1527         struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1528         __be32          seq;
1529         struct kvec     iov;
1530         struct xdr_buf  verf_buf;
1531         struct xdr_netobj mic;
1532         u32             flav,len;
1533         u32             maj_stat;
1534         __be32          *ret = ERR_PTR(-EIO);
1535
1536         dprintk("RPC: %5u %s\n", task->tk_pid, __func__);
1537
1538         flav = ntohl(*p++);
1539         if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE)
1540                 goto out_bad;
1541         if (flav != RPC_AUTH_GSS)
1542                 goto out_bad;
1543         seq = htonl(task->tk_rqstp->rq_seqno);
1544         iov.iov_base = &seq;
1545         iov.iov_len = sizeof(seq);
1546         xdr_buf_from_iov(&iov, &verf_buf);
1547         mic.data = (u8 *)p;
1548         mic.len = len;
1549
1550         ret = ERR_PTR(-EACCES);
1551         maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
1552         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1553                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1554         if (maj_stat) {
1555                 dprintk("RPC: %5u %s: gss_verify_mic returned error 0x%08x\n",
1556                         task->tk_pid, __func__, maj_stat);
1557                 goto out_bad;
1558         }
1559         /* We leave it to unwrap to calculate au_rslack. For now we just
1560          * calculate the length of the verifier: */
1561         cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2;
1562         gss_put_ctx(ctx);
1563         dprintk("RPC: %5u %s: gss_verify_mic succeeded.\n",
1564                         task->tk_pid, __func__);
1565         return p + XDR_QUADLEN(len);
1566 out_bad:
1567         gss_put_ctx(ctx);
1568         dprintk("RPC: %5u %s failed ret %ld.\n", task->tk_pid, __func__,
1569                 PTR_ERR(ret));
1570         return ret;
1571 }
1572
1573 static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
1574                                 __be32 *p, void *obj)
1575 {
1576         struct xdr_stream xdr;
1577
1578         xdr_init_encode(&xdr, &rqstp->rq_snd_buf, p);
1579         encode(rqstp, &xdr, obj);
1580 }
1581
1582 static inline int
1583 gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1584                    kxdreproc_t encode, struct rpc_rqst *rqstp,
1585                    __be32 *p, void *obj)
1586 {
1587         struct xdr_buf  *snd_buf = &rqstp->rq_snd_buf;
1588         struct xdr_buf  integ_buf;
1589         __be32          *integ_len = NULL;
1590         struct xdr_netobj mic;
1591         u32             offset;
1592         __be32          *q;
1593         struct kvec     *iov;
1594         u32             maj_stat = 0;
1595         int             status = -EIO;
1596
1597         integ_len = p++;
1598         offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
1599         *p++ = htonl(rqstp->rq_seqno);
1600
1601         gss_wrap_req_encode(encode, rqstp, p, obj);
1602
1603         if (xdr_buf_subsegment(snd_buf, &integ_buf,
1604                                 offset, snd_buf->len - offset))
1605                 return status;
1606         *integ_len = htonl(integ_buf.len);
1607
1608         /* guess whether we're in the head or the tail: */
1609         if (snd_buf->page_len || snd_buf->tail[0].iov_len)
1610                 iov = snd_buf->tail;
1611         else
1612                 iov = snd_buf->head;
1613         p = iov->iov_base + iov->iov_len;
1614         mic.data = (u8 *)(p + 1);
1615
1616         maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
1617         status = -EIO; /* XXX? */
1618         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1619                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1620         else if (maj_stat)
1621                 return status;
1622         q = xdr_encode_opaque(p, NULL, mic.len);
1623
1624         offset = (u8 *)q - (u8 *)p;
1625         iov->iov_len += offset;
1626         snd_buf->len += offset;
1627         return 0;
1628 }
1629
1630 static void
1631 priv_release_snd_buf(struct rpc_rqst *rqstp)
1632 {
1633         int i;
1634
1635         for (i=0; i < rqstp->rq_enc_pages_num; i++)
1636                 __free_page(rqstp->rq_enc_pages[i]);
1637         kfree(rqstp->rq_enc_pages);
1638 }
1639
1640 static int
1641 alloc_enc_pages(struct rpc_rqst *rqstp)
1642 {
1643         struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
1644         int first, last, i;
1645
1646         if (snd_buf->page_len == 0) {
1647                 rqstp->rq_enc_pages_num = 0;
1648                 return 0;
1649         }
1650
1651         first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
1652         last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT;
1653         rqstp->rq_enc_pages_num = last - first + 1 + 1;
1654         rqstp->rq_enc_pages
1655                 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *),
1656                                 GFP_NOFS);
1657         if (!rqstp->rq_enc_pages)
1658                 goto out;
1659         for (i=0; i < rqstp->rq_enc_pages_num; i++) {
1660                 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS);
1661                 if (rqstp->rq_enc_pages[i] == NULL)
1662                         goto out_free;
1663         }
1664         rqstp->rq_release_snd_buf = priv_release_snd_buf;
1665         return 0;
1666 out_free:
1667         rqstp->rq_enc_pages_num = i;
1668         priv_release_snd_buf(rqstp);
1669 out:
1670         return -EAGAIN;
1671 }
1672
1673 static inline int
1674 gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1675                   kxdreproc_t encode, struct rpc_rqst *rqstp,
1676                   __be32 *p, void *obj)
1677 {
1678         struct xdr_buf  *snd_buf = &rqstp->rq_snd_buf;
1679         u32             offset;
1680         u32             maj_stat;
1681         int             status;
1682         __be32          *opaque_len;
1683         struct page     **inpages;
1684         int             first;
1685         int             pad;
1686         struct kvec     *iov;
1687         char            *tmp;
1688
1689         opaque_len = p++;
1690         offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
1691         *p++ = htonl(rqstp->rq_seqno);
1692
1693         gss_wrap_req_encode(encode, rqstp, p, obj);
1694
1695         status = alloc_enc_pages(rqstp);
1696         if (status)
1697                 return status;
1698         first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
1699         inpages = snd_buf->pages + first;
1700         snd_buf->pages = rqstp->rq_enc_pages;
1701         snd_buf->page_base -= first << PAGE_CACHE_SHIFT;
1702         /*
1703          * Give the tail its own page, in case we need extra space in the
1704          * head when wrapping:
1705          *
1706          * call_allocate() allocates twice the slack space required
1707          * by the authentication flavor to rq_callsize.
1708          * For GSS, slack is GSS_CRED_SLACK.
1709          */
1710         if (snd_buf->page_len || snd_buf->tail[0].iov_len) {
1711                 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]);
1712                 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len);
1713                 snd_buf->tail[0].iov_base = tmp;
1714         }
1715         maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages);
1716         /* slack space should prevent this ever happening: */
1717         BUG_ON(snd_buf->len > snd_buf->buflen);
1718         status = -EIO;
1719         /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was
1720          * done anyway, so it's safe to put the request on the wire: */
1721         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1722                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1723         else if (maj_stat)
1724                 return status;
1725
1726         *opaque_len = htonl(snd_buf->len - offset);
1727         /* guess whether we're in the head or the tail: */
1728         if (snd_buf->page_len || snd_buf->tail[0].iov_len)
1729                 iov = snd_buf->tail;
1730         else
1731                 iov = snd_buf->head;
1732         p = iov->iov_base + iov->iov_len;
1733         pad = 3 - ((snd_buf->len - offset - 1) & 3);
1734         memset(p, 0, pad);
1735         iov->iov_len += pad;
1736         snd_buf->len += pad;
1737
1738         return 0;
1739 }
1740
1741 static int
1742 gss_wrap_req(struct rpc_task *task,
1743              kxdreproc_t encode, void *rqstp, __be32 *p, void *obj)
1744 {
1745         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1746         struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1747                         gc_base);
1748         struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1749         int             status = -EIO;
1750
1751         dprintk("RPC: %5u %s\n", task->tk_pid, __func__);
1752         if (ctx->gc_proc != RPC_GSS_PROC_DATA) {
1753                 /* The spec seems a little ambiguous here, but I think that not
1754                  * wrapping context destruction requests makes the most sense.
1755                  */
1756                 gss_wrap_req_encode(encode, rqstp, p, obj);
1757                 status = 0;
1758                 goto out;
1759         }
1760         switch (gss_cred->gc_service) {
1761         case RPC_GSS_SVC_NONE:
1762                 gss_wrap_req_encode(encode, rqstp, p, obj);
1763                 status = 0;
1764                 break;
1765         case RPC_GSS_SVC_INTEGRITY:
1766                 status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj);
1767                 break;
1768         case RPC_GSS_SVC_PRIVACY:
1769                 status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj);
1770                 break;
1771         }
1772 out:
1773         gss_put_ctx(ctx);
1774         dprintk("RPC: %5u %s returning %d\n", task->tk_pid, __func__, status);
1775         return status;
1776 }
1777
1778 static inline int
1779 gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1780                 struct rpc_rqst *rqstp, __be32 **p)
1781 {
1782         struct xdr_buf  *rcv_buf = &rqstp->rq_rcv_buf;
1783         struct xdr_buf integ_buf;
1784         struct xdr_netobj mic;
1785         u32 data_offset, mic_offset;
1786         u32 integ_len;
1787         u32 maj_stat;
1788         int status = -EIO;
1789
1790         integ_len = ntohl(*(*p)++);
1791         if (integ_len & 3)
1792                 return status;
1793         data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
1794         mic_offset = integ_len + data_offset;
1795         if (mic_offset > rcv_buf->len)
1796                 return status;
1797         if (ntohl(*(*p)++) != rqstp->rq_seqno)
1798                 return status;
1799
1800         if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset,
1801                                 mic_offset - data_offset))
1802                 return status;
1803
1804         if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset))
1805                 return status;
1806
1807         maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
1808         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1809                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1810         if (maj_stat != GSS_S_COMPLETE)
1811                 return status;
1812         return 0;
1813 }
1814
1815 static inline int
1816 gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1817                 struct rpc_rqst *rqstp, __be32 **p)
1818 {
1819         struct xdr_buf  *rcv_buf = &rqstp->rq_rcv_buf;
1820         u32 offset;
1821         u32 opaque_len;
1822         u32 maj_stat;
1823         int status = -EIO;
1824
1825         opaque_len = ntohl(*(*p)++);
1826         offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
1827         if (offset + opaque_len > rcv_buf->len)
1828                 return status;
1829         /* remove padding: */
1830         rcv_buf->len = offset + opaque_len;
1831
1832         maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf);
1833         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1834                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1835         if (maj_stat != GSS_S_COMPLETE)
1836                 return status;
1837         if (ntohl(*(*p)++) != rqstp->rq_seqno)
1838                 return status;
1839
1840         return 0;
1841 }
1842
1843 static int
1844 gss_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
1845                       __be32 *p, void *obj)
1846 {
1847         struct xdr_stream xdr;
1848
1849         xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
1850         return decode(rqstp, &xdr, obj);
1851 }
1852
1853 static int
1854 gss_unwrap_resp(struct rpc_task *task,
1855                 kxdrdproc_t decode, void *rqstp, __be32 *p, void *obj)
1856 {
1857         struct rpc_cred *cred = task->tk_rqstp->rq_cred;
1858         struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1859                         gc_base);
1860         struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1861         __be32          *savedp = p;
1862         struct kvec     *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head;
1863         int             savedlen = head->iov_len;
1864         int             status = -EIO;
1865
1866         if (ctx->gc_proc != RPC_GSS_PROC_DATA)
1867                 goto out_decode;
1868         switch (gss_cred->gc_service) {
1869         case RPC_GSS_SVC_NONE:
1870                 break;
1871         case RPC_GSS_SVC_INTEGRITY:
1872                 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p);
1873                 if (status)
1874                         goto out;
1875                 break;
1876         case RPC_GSS_SVC_PRIVACY:
1877                 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p);
1878                 if (status)
1879                         goto out;
1880                 break;
1881         }
1882         /* take into account extra slack for integrity and privacy cases: */
1883         cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp)
1884                                                 + (savedlen - head->iov_len);
1885 out_decode:
1886         status = gss_unwrap_req_decode(decode, rqstp, p, obj);
1887 out:
1888         gss_put_ctx(ctx);
1889         dprintk("RPC: %5u %s returning %d\n",
1890                 task->tk_pid, __func__, status);
1891         return status;
1892 }
1893
1894 static const struct rpc_authops authgss_ops = {
1895         .owner          = THIS_MODULE,
1896         .au_flavor      = RPC_AUTH_GSS,
1897         .au_name        = "RPCSEC_GSS",
1898         .create         = gss_create,
1899         .destroy        = gss_destroy,
1900         .lookup_cred    = gss_lookup_cred,
1901         .crcreate       = gss_create_cred,
1902         .list_pseudoflavors = gss_mech_list_pseudoflavors,
1903         .info2flavor    = gss_mech_info2flavor,
1904         .flavor2info    = gss_mech_flavor2info,
1905 };
1906
1907 static const struct rpc_credops gss_credops = {
1908         .cr_name        = "AUTH_GSS",
1909         .crdestroy      = gss_destroy_cred,
1910         .cr_init        = gss_cred_init,
1911         .crbind         = rpcauth_generic_bind_cred,
1912         .crmatch        = gss_match,
1913         .crmarshal      = gss_marshal,
1914         .crrefresh      = gss_refresh,
1915         .crvalidate     = gss_validate,
1916         .crwrap_req     = gss_wrap_req,
1917         .crunwrap_resp  = gss_unwrap_resp,
1918         .crkey_timeout  = gss_key_timeout,
1919 };
1920
1921 static const struct rpc_credops gss_nullops = {
1922         .cr_name        = "AUTH_GSS",
1923         .crdestroy      = gss_destroy_nullcred,
1924         .crbind         = rpcauth_generic_bind_cred,
1925         .crmatch        = gss_match,
1926         .crmarshal      = gss_marshal,
1927         .crrefresh      = gss_refresh_null,
1928         .crvalidate     = gss_validate,
1929         .crwrap_req     = gss_wrap_req,
1930         .crunwrap_resp  = gss_unwrap_resp,
1931 };
1932
1933 static const struct rpc_pipe_ops gss_upcall_ops_v0 = {
1934         .upcall         = rpc_pipe_generic_upcall,
1935         .downcall       = gss_pipe_downcall,
1936         .destroy_msg    = gss_pipe_destroy_msg,
1937         .open_pipe      = gss_pipe_open_v0,
1938         .release_pipe   = gss_pipe_release,
1939 };
1940
1941 static const struct rpc_pipe_ops gss_upcall_ops_v1 = {
1942         .upcall         = rpc_pipe_generic_upcall,
1943         .downcall       = gss_pipe_downcall,
1944         .destroy_msg    = gss_pipe_destroy_msg,
1945         .open_pipe      = gss_pipe_open_v1,
1946         .release_pipe   = gss_pipe_release,
1947 };
1948
1949 static __net_init int rpcsec_gss_init_net(struct net *net)
1950 {
1951         return gss_svc_init_net(net);
1952 }
1953
1954 static __net_exit void rpcsec_gss_exit_net(struct net *net)
1955 {
1956         gss_svc_shutdown_net(net);
1957 }
1958
1959 static struct pernet_operations rpcsec_gss_net_ops = {
1960         .init = rpcsec_gss_init_net,
1961         .exit = rpcsec_gss_exit_net,
1962 };
1963
1964 /*
1965  * Initialize RPCSEC_GSS module
1966  */
1967 static int __init init_rpcsec_gss(void)
1968 {
1969         int err = 0;
1970
1971         err = rpcauth_register(&authgss_ops);
1972         if (err)
1973                 goto out;
1974         err = gss_svc_init();
1975         if (err)
1976                 goto out_unregister;
1977         err = register_pernet_subsys(&rpcsec_gss_net_ops);
1978         if (err)
1979                 goto out_svc_exit;
1980         rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version");
1981         return 0;
1982 out_svc_exit:
1983         gss_svc_shutdown();
1984 out_unregister:
1985         rpcauth_unregister(&authgss_ops);
1986 out:
1987         return err;
1988 }
1989
1990 static void __exit exit_rpcsec_gss(void)
1991 {
1992         unregister_pernet_subsys(&rpcsec_gss_net_ops);
1993         gss_svc_shutdown();
1994         rpcauth_unregister(&authgss_ops);
1995         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1996 }
1997
1998 MODULE_ALIAS("rpc-auth-6");
1999 MODULE_LICENSE("GPL");
2000 module_param_named(expired_cred_retry_delay,
2001                    gss_expired_cred_retry_delay,
2002                    uint, 0644);
2003 MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until "
2004                 "the RPC engine retries an expired credential");
2005
2006 module_param_named(key_expire_timeo,
2007                    gss_key_expire_timeo,
2008                    uint, 0644);
2009 MODULE_PARM_DESC(key_expire_timeo, "Time (in seconds) at the end of a "
2010                 "credential keys lifetime where the NFS layer cleans up "
2011                 "prior to key expiration");
2012
2013 module_init(init_rpcsec_gss)
2014 module_exit(exit_rpcsec_gss)