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  * $Id$
  38  */
  39
  40
  41 #include <linux/module.h>
  42 #include <linux/init.h>
  43 #include <linux/types.h>
  44 #include <linux/slab.h>
  45 #include <linux/sched.h>
  46 #include <linux/pagemap.h>
  47 #include <linux/sunrpc/clnt.h>
  48 #include <linux/sunrpc/auth.h>
  49 #include <linux/sunrpc/auth_gss.h>
  50 #include <linux/sunrpc/svcauth_gss.h>
  51 #include <linux/sunrpc/gss_err.h>
  52 #include <linux/workqueue.h>
  53 #include <linux/sunrpc/rpc_pipe_fs.h>
  54 #include <linux/sunrpc/gss_api.h>
  55 #include <asm/uaccess.h>
  56
  57 static const struct rpc_authops authgss_ops;
  58
  59 static const struct rpc_credops gss_credops;
  60
  61 #ifdef RPC_DEBUG
  62 # define RPCDBG_FACILITY        RPCDBG_AUTH
  63 #endif
  64
  65 #define NFS_NGROUPS     16
  66
  67 #define GSS_CRED_EXPIRE         (60 * HZ)       /* XXX: reasonable? */
  68 #define GSS_CRED_SLACK          1024            /* XXX: unused */
  69 /* length of a krb5 verifier (48), plus data added before arguments when
  70  * using integrity (two 4-byte integers): */
  71 #define GSS_VERF_SLACK          100
  72
  73 /* XXX this define must match the gssd define
  74 * as it is passed to gssd to signal the use of
  75 * machine creds should be part of the shared rpc interface */
  76
  77 #define CA_RUN_AS_MACHINE  0x00000200
  78
  79 /* dump the buffer in `emacs-hexl' style */
  80 #define isprint(c)      ((c > 0x1f) && (c < 0x7f))
  81
  82 static DEFINE_RWLOCK(gss_ctx_lock);
  83
  84 struct gss_auth {
  85         struct rpc_auth rpc_auth;
  86         struct gss_api_mech *mech;
  87         enum rpc_gss_svc service;
  88         struct rpc_clnt *client;
  89         struct dentry *dentry;
  90 };
  91
  92 static void gss_destroy_ctx(struct gss_cl_ctx *);
  93 static struct rpc_pipe_ops gss_upcall_ops;
  94
  95 static inline struct gss_cl_ctx *
  96 gss_get_ctx(struct gss_cl_ctx *ctx)
  97 {
  98         atomic_inc(&ctx->count);
  99         return ctx;
 100 }
 101
 102 static inline void
 103 gss_put_ctx(struct gss_cl_ctx *ctx)
 104 {
 105         if (atomic_dec_and_test(&ctx->count))
 106                 gss_destroy_ctx(ctx);
 107 }
 108
 109 static void
 110 gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
 111 {
 112         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
 113         struct gss_cl_ctx *old;
 114         write_lock(&gss_ctx_lock);
 115         old = gss_cred->gc_ctx;
 116         gss_cred->gc_ctx = ctx;
 117         set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 118         clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags);
 119         write_unlock(&gss_ctx_lock);
 120         if (old)
 121                 gss_put_ctx(old);
 122 }
 123
 124 static int
 125 gss_cred_is_uptodate_ctx(struct rpc_cred *cred)
 126 {
 127         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
 128         int res = 0;
 129
 130         read_lock(&gss_ctx_lock);
 131         if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) && gss_cred->gc_ctx)
 132                 res = 1;
 133         read_unlock(&gss_ctx_lock);
 134         return res;
 135 }
 136
 137 static const void *
 138 simple_get_bytes(const void *p, const void *end, void *res, size_t len)
 139 {
 140         const void *q = (const void *)((const char *)p + len);
 141         if (unlikely(q > end || q < p))
 142                 return ERR_PTR(-EFAULT);
 143         memcpy(res, p, len);
 144         return q;
 145 }
 146
 147 static inline const void *
 148 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest)
 149 {
 150         const void *q;
 151         unsigned int len;
 152
 153         p = simple_get_bytes(p, end, &len, sizeof(len));
 154         if (IS_ERR(p))
 155                 return p;
 156         q = (const void *)((const char *)p + len);
 157         if (unlikely(q > end || q < p))
 158                 return ERR_PTR(-EFAULT);
 159         dest->data = kmemdup(p, len, GFP_KERNEL);
 160         if (unlikely(dest->data == NULL))
 161                 return ERR_PTR(-ENOMEM);
 162         dest->len = len;
 163         return q;
 164 }
 165
 166 static struct gss_cl_ctx *
 167 gss_cred_get_ctx(struct rpc_cred *cred)
 168 {
 169         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
 170         struct gss_cl_ctx *ctx = NULL;
 171
 172         read_lock(&gss_ctx_lock);
 173         if (gss_cred->gc_ctx)
 174                 ctx = gss_get_ctx(gss_cred->gc_ctx);
 175         read_unlock(&gss_ctx_lock);
 176         return ctx;
 177 }
 178
 179 static struct gss_cl_ctx *
 180 gss_alloc_context(void)
 181 {
 182         struct gss_cl_ctx *ctx;
 183
 184         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
 185         if (ctx != NULL) {
 186                 ctx->gc_proc = RPC_GSS_PROC_DATA;
 187                 ctx->gc_seq = 1;        /* NetApp 6.4R1 doesn't accept seq. no. 0 */
 188                 spin_lock_init(&ctx->gc_seq_lock);
 189                 atomic_set(&ctx->count,1);
 190         }
 191         return ctx;
 192 }
 193
 194 #define GSSD_MIN_TIMEOUT (60 * 60)
 195 static const void *
 196 gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm)
 197 {
 198         const void *q;
 199         unsigned int seclen;
 200         unsigned int timeout;
 201         u32 window_size;
 202         int ret;
 203
 204         /* First unsigned int gives the lifetime (in seconds) of the cred */
 205         p = simple_get_bytes(p, end, &timeout, sizeof(timeout));
 206         if (IS_ERR(p))
 207                 goto err;
 208         if (timeout == 0)
 209                 timeout = GSSD_MIN_TIMEOUT;
 210         ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4;
 211         /* Sequence number window. Determines the maximum number of simultaneous requests */
 212         p = simple_get_bytes(p, end, &window_size, sizeof(window_size));
 213         if (IS_ERR(p))
 214                 goto err;
 215         ctx->gc_win = window_size;
 216         /* gssd signals an error by passing ctx->gc_win = 0: */
 217         if (ctx->gc_win == 0) {
 218                 /* in which case, p points to  an error code which we ignore */
 219                 p = ERR_PTR(-EACCES);
 220                 goto err;
 221         }
 222         /* copy the opaque wire context */
 223         p = simple_get_netobj(p, end, &ctx->gc_wire_ctx);
 224         if (IS_ERR(p))
 225                 goto err;
 226         /* import the opaque security context */
 227         p  = simple_get_bytes(p, end, &seclen, sizeof(seclen));
 228         if (IS_ERR(p))
 229                 goto err;
 230         q = (const void *)((const char *)p + seclen);
 231         if (unlikely(q > end || q < p)) {
 232                 p = ERR_PTR(-EFAULT);
 233                 goto err;
 234         }
 235         ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx);
 236         if (ret < 0) {
 237                 p = ERR_PTR(ret);
 238                 goto err;
 239         }
 240         return q;
 241 err:
 242         dprintk("RPC:       gss_fill_context returning %ld\n", -PTR_ERR(p));
 243         return p;
 244 }
 245
 246
 247 struct gss_upcall_msg {
 248         atomic_t count;
 249         uid_t   uid;
 250         struct rpc_pipe_msg msg;
 251         struct list_head list;
 252         struct gss_auth *auth;
 253         struct rpc_wait_queue rpc_waitqueue;
 254         wait_queue_head_t waitqueue;
 255         struct gss_cl_ctx *ctx;
 256 };
 257
 258 static void
 259 gss_release_msg(struct gss_upcall_msg *gss_msg)
 260 {
 261         if (!atomic_dec_and_test(&gss_msg->count))
 262                 return;
 263         BUG_ON(!list_empty(&gss_msg->list));
 264         if (gss_msg->ctx != NULL)
 265                 gss_put_ctx(gss_msg->ctx);
 266         kfree(gss_msg);
 267 }
 268
 269 static struct gss_upcall_msg *
 270 __gss_find_upcall(struct rpc_inode *rpci, uid_t uid)
 271 {
 272         struct gss_upcall_msg *pos;
 273         list_for_each_entry(pos, &rpci->in_downcall, list) {
 274                 if (pos->uid != uid)
 275                         continue;
 276                 atomic_inc(&pos->count);
 277                 dprintk("RPC:       gss_find_upcall found msg %p\n", pos);
 278                 return pos;
 279         }
 280         dprintk("RPC:       gss_find_upcall found nothing\n");
 281         return NULL;
 282 }
 283
 284 /* Try to add a upcall to the pipefs queue.
 285  * If an upcall owned by our uid already exists, then we return a reference
 286  * to that upcall instead of adding the new upcall.
 287  */
 288 static inline struct gss_upcall_msg *
 289 gss_add_msg(struct gss_auth *gss_auth, struct gss_upcall_msg *gss_msg)
 290 {
 291         struct inode *inode = gss_auth->dentry->d_inode;
 292         struct rpc_inode *rpci = RPC_I(inode);
 293         struct gss_upcall_msg *old;
 294
 295         spin_lock(&inode->i_lock);
 296         old = __gss_find_upcall(rpci, gss_msg->uid);
 297         if (old == NULL) {
 298                 atomic_inc(&gss_msg->count);
 299                 list_add(&gss_msg->list, &rpci->in_downcall);
 300         } else
 301                 gss_msg = old;
 302         spin_unlock(&inode->i_lock);
 303         return gss_msg;
 304 }
 305
 306 static void
 307 __gss_unhash_msg(struct gss_upcall_msg *gss_msg)
 308 {
 309         list_del_init(&gss_msg->list);
 310         rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
 311         wake_up_all(&gss_msg->waitqueue);
 312         atomic_dec(&gss_msg->count);
 313 }
 314
 315 static void
 316 gss_unhash_msg(struct gss_upcall_msg *gss_msg)
 317 {
 318         struct gss_auth *gss_auth = gss_msg->auth;
 319         struct inode *inode = gss_auth->dentry->d_inode;
 320
 321         if (list_empty(&gss_msg->list))
 322                 return;
 323         spin_lock(&inode->i_lock);
 324         if (!list_empty(&gss_msg->list))
 325                 __gss_unhash_msg(gss_msg);
 326         spin_unlock(&inode->i_lock);
 327 }
 328
 329 static void
 330 gss_upcall_callback(struct rpc_task *task)
 331 {
 332         struct gss_cred *gss_cred = container_of(task->tk_msg.rpc_cred,
 333                         struct gss_cred, gc_base);
 334         struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall;
 335         struct inode *inode = gss_msg->auth->dentry->d_inode;
 336
 337         if (gss_msg->ctx)
 338                 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_get_ctx(gss_msg->ctx));
 339         else
 340                 task->tk_status = gss_msg->msg.errno;
 341         spin_lock(&inode->i_lock);
 342         gss_cred->gc_upcall = NULL;
 343         rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
 344         spin_unlock(&inode->i_lock);
 345         gss_release_msg(gss_msg);
 346 }
 347
 348 static inline struct gss_upcall_msg *
 349 gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid)
 350 {
 351         struct gss_upcall_msg *gss_msg;
 352
 353         gss_msg = kzalloc(sizeof(*gss_msg), GFP_KERNEL);
 354         if (gss_msg != NULL) {
 355                 INIT_LIST_HEAD(&gss_msg->list);
 356                 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
 357                 init_waitqueue_head(&gss_msg->waitqueue);
 358                 atomic_set(&gss_msg->count, 1);
 359                 gss_msg->msg.data = &gss_msg->uid;
 360                 gss_msg->msg.len = sizeof(gss_msg->uid);
 361                 gss_msg->uid = uid;
 362                 gss_msg->auth = gss_auth;
 363         }
 364         return gss_msg;
 365 }
 366
 367 static struct gss_upcall_msg *
 368 gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred)
 369 {
 370         struct gss_upcall_msg *gss_new, *gss_msg;
 371
 372         gss_new = gss_alloc_msg(gss_auth, cred->cr_uid);
 373         if (gss_new == NULL)
 374                 return ERR_PTR(-ENOMEM);
 375         gss_msg = gss_add_msg(gss_auth, gss_new);
 376         if (gss_msg == gss_new) {
 377                 int res = rpc_queue_upcall(gss_auth->dentry->d_inode, &gss_new->msg);
 378                 if (res) {
 379                         gss_unhash_msg(gss_new);
 380                         gss_msg = ERR_PTR(res);
 381                 }
 382         } else
 383                 gss_release_msg(gss_new);
 384         return gss_msg;
 385 }
 386
 387 static inline int
 388 gss_refresh_upcall(struct rpc_task *task)
 389 {
 390         struct rpc_cred *cred = task->tk_msg.rpc_cred;
 391         struct gss_auth *gss_auth = container_of(cred->cr_auth,
 392                         struct gss_auth, rpc_auth);
 393         struct gss_cred *gss_cred = container_of(cred,
 394                         struct gss_cred, gc_base);
 395         struct gss_upcall_msg *gss_msg;
 396         struct inode *inode = gss_auth->dentry->d_inode;
 397         int err = 0;
 398
 399         dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid,
 400                                                                 cred->cr_uid);
 401         gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred);
 402         if (IS_ERR(gss_msg)) {
 403                 err = PTR_ERR(gss_msg);
 404                 goto out;
 405         }
 406         spin_lock(&inode->i_lock);
 407         if (gss_cred->gc_upcall != NULL)
 408                 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL, NULL);
 409         else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) {
 410                 task->tk_timeout = 0;
 411                 gss_cred->gc_upcall = gss_msg;
 412                 /* gss_upcall_callback will release the reference to gss_upcall_msg */
 413                 atomic_inc(&gss_msg->count);
 414                 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback, NULL);
 415         } else
 416                 err = gss_msg->msg.errno;
 417         spin_unlock(&inode->i_lock);
 418         gss_release_msg(gss_msg);
 419 out:
 420         dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n",
 421                         task->tk_pid, cred->cr_uid, err);
 422         return err;
 423 }
 424
 425 static inline int
 426 gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
 427 {
 428         struct inode *inode = gss_auth->dentry->d_inode;
 429         struct rpc_cred *cred = &gss_cred->gc_base;
 430         struct gss_upcall_msg *gss_msg;
 431         DEFINE_WAIT(wait);
 432         int err = 0;
 433
 434         dprintk("RPC:       gss_upcall for uid %u\n", cred->cr_uid);
 435         gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred);
 436         if (IS_ERR(gss_msg)) {
 437                 err = PTR_ERR(gss_msg);
 438                 goto out;
 439         }
 440         for (;;) {
 441                 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE);
 442                 spin_lock(&inode->i_lock);
 443                 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) {
 444                         spin_unlock(&inode->i_lock);
 445                         break;
 446                 }
 447                 spin_unlock(&inode->i_lock);
 448                 if (signalled()) {
 449                         err = -ERESTARTSYS;
 450                         goto out_intr;
 451                 }
 452                 schedule();
 453         }
 454         if (gss_msg->ctx)
 455                 gss_cred_set_ctx(cred, gss_get_ctx(gss_msg->ctx));
 456         else
 457                 err = gss_msg->msg.errno;
 458 out_intr:
 459         finish_wait(&gss_msg->waitqueue, &wait);
 460         gss_release_msg(gss_msg);
 461 out:
 462         dprintk("RPC:       gss_create_upcall for uid %u result %d\n",
 463                         cred->cr_uid, err);
 464         return err;
 465 }
 466
 467 static ssize_t
 468 gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg,
 469                 char __user *dst, size_t buflen)
 470 {
 471         char *data = (char *)msg->data + msg->copied;
 472         ssize_t mlen = msg->len;
 473         ssize_t left;
 474
 475         if (mlen > buflen)
 476                 mlen = buflen;
 477         left = copy_to_user(dst, data, mlen);
 478         if (left < 0) {
 479                 msg->errno = left;
 480                 return left;
 481         }
 482         mlen -= left;
 483         msg->copied += mlen;
 484         msg->errno = 0;
 485         return mlen;
 486 }
 487
 488 #define MSG_BUF_MAXSIZE 1024
 489
 490 static ssize_t
 491 gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 492 {
 493         const void *p, *end;
 494         void *buf;
 495         struct rpc_clnt *clnt;
 496         struct gss_upcall_msg *gss_msg;
 497         struct inode *inode = filp->f_path.dentry->d_inode;
 498         struct gss_cl_ctx *ctx;
 499         uid_t uid;
 500         ssize_t err = -EFBIG;
 501
 502         if (mlen > MSG_BUF_MAXSIZE)
 503                 goto out;
 504         err = -ENOMEM;
 505         buf = kmalloc(mlen, GFP_KERNEL);
 506         if (!buf)
 507                 goto out;
 508
 509         clnt = RPC_I(inode)->private;
 510         err = -EFAULT;
 511         if (copy_from_user(buf, src, mlen))
 512                 goto err;
 513
 514         end = (const void *)((char *)buf + mlen);
 515         p = simple_get_bytes(buf, end, &uid, sizeof(uid));
 516         if (IS_ERR(p)) {
 517                 err = PTR_ERR(p);
 518                 goto err;
 519         }
 520
 521         err = -ENOMEM;
 522         ctx = gss_alloc_context();
 523         if (ctx == NULL)
 524                 goto err;
 525
 526         err = -ENOENT;
 527         /* Find a matching upcall */
 528         spin_lock(&inode->i_lock);
 529         gss_msg = __gss_find_upcall(RPC_I(inode), uid);
 530         if (gss_msg == NULL) {
 531                 spin_unlock(&inode->i_lock);
 532                 goto err_put_ctx;
 533         }
 534         list_del_init(&gss_msg->list);
 535         spin_unlock(&inode->i_lock);
 536
 537         p = gss_fill_context(p, end, ctx, gss_msg->auth->mech);
 538         if (IS_ERR(p)) {
 539                 err = PTR_ERR(p);
 540                 gss_msg->msg.errno = (err == -EACCES) ? -EACCES : -EAGAIN;
 541                 goto err_release_msg;
 542         }
 543         gss_msg->ctx = gss_get_ctx(ctx);
 544         err = mlen;
 545
 546 err_release_msg:
 547         spin_lock(&inode->i_lock);
 548         __gss_unhash_msg(gss_msg);
 549         spin_unlock(&inode->i_lock);
 550         gss_release_msg(gss_msg);
 551 err_put_ctx:
 552         gss_put_ctx(ctx);
 553 err:
 554         kfree(buf);
 555 out:
 556         dprintk("RPC:       gss_pipe_downcall returning %Zd\n", err);
 557         return err;
 558 }
 559
 560 static void
 561 gss_pipe_release(struct inode *inode)
 562 {
 563         struct rpc_inode *rpci = RPC_I(inode);
 564         struct gss_upcall_msg *gss_msg;
 565
 566         spin_lock(&inode->i_lock);
 567         while (!list_empty(&rpci->in_downcall)) {
 568
 569                 gss_msg = list_entry(rpci->in_downcall.next,
 570                                 struct gss_upcall_msg, list);
 571                 gss_msg->msg.errno = -EPIPE;
 572                 atomic_inc(&gss_msg->count);
 573                 __gss_unhash_msg(gss_msg);
 574                 spin_unlock(&inode->i_lock);
 575                 gss_release_msg(gss_msg);
 576                 spin_lock(&inode->i_lock);
 577         }
 578         spin_unlock(&inode->i_lock);
 579 }
 580
 581 static void
 582 gss_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 583 {
 584         struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg);
 585         static unsigned long ratelimit;
 586
 587         if (msg->errno < 0) {
 588                 dprintk("RPC:       gss_pipe_destroy_msg releasing msg %p\n",
 589                                 gss_msg);
 590                 atomic_inc(&gss_msg->count);
 591                 gss_unhash_msg(gss_msg);
 592                 if (msg->errno == -ETIMEDOUT) {
 593                         unsigned long now = jiffies;
 594                         if (time_after(now, ratelimit)) {
 595                                 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n"
 596                                                     "Please check user daemon is running!\n");
 597                                 ratelimit = now + 15*HZ;
 598                         }
 599                 }
 600                 gss_release_msg(gss_msg);
 601         }
 602 }
 603
 604 /*
 605  * NOTE: we have the opportunity to use different
 606  * parameters based on the input flavor (which must be a pseudoflavor)
 607  */
 608 static struct rpc_auth *
 609 gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 610 {
 611         struct gss_auth *gss_auth;
 612         struct rpc_auth * auth;
 613         int err = -ENOMEM; /* XXX? */
 614
 615         dprintk("RPC:       creating GSS authenticator for client %p\n", clnt);
 616
 617         if (!try_module_get(THIS_MODULE))
 618                 return ERR_PTR(err);
 619         if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL)))
 620                 goto out_dec;
 621         gss_auth->client = clnt;
 622         err = -EINVAL;
 623         gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor);
 624         if (!gss_auth->mech) {
 625                 printk(KERN_WARNING "%s: Pseudoflavor %d not found!",
 626                                 __FUNCTION__, flavor);
 627                 goto err_free;
 628         }
 629         gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
 630         if (gss_auth->service == 0)
 631                 goto err_put_mech;
 632         auth = &gss_auth->rpc_auth;
 633         auth->au_cslack = GSS_CRED_SLACK >> 2;
 634         auth->au_rslack = GSS_VERF_SLACK >> 2;
 635         auth->au_ops = &authgss_ops;
 636         auth->au_flavor = flavor;
 637         atomic_set(&auth->au_count, 1);
 638
 639         gss_auth->dentry = rpc_mkpipe(clnt->cl_dentry, gss_auth->mech->gm_name,
 640                         clnt, &gss_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
 641         if (IS_ERR(gss_auth->dentry)) {
 642                 err = PTR_ERR(gss_auth->dentry);
 643                 goto err_put_mech;
 644         }
 645
 646         err = rpcauth_init_credcache(auth, GSS_CRED_EXPIRE);
 647         if (err)
 648                 goto err_unlink_pipe;
 649
 650         return auth;
 651 err_unlink_pipe:
 652         rpc_unlink(gss_auth->dentry);
 653 err_put_mech:
 654         gss_mech_put(gss_auth->mech);
 655 err_free:
 656         kfree(gss_auth);
 657 out_dec:
 658         module_put(THIS_MODULE);
 659         return ERR_PTR(err);
 660 }
 661
 662 static void
 663 gss_destroy(struct rpc_auth *auth)
 664 {
 665         struct gss_auth *gss_auth;
 666
 667         dprintk("RPC:       destroying GSS authenticator %p flavor %d\n",
 668                         auth, auth->au_flavor);
 669
 670         rpcauth_destroy_credcache(auth);
 671
 672         gss_auth = container_of(auth, struct gss_auth, rpc_auth);
 673         rpc_unlink(gss_auth->dentry);
 674         gss_auth->dentry = NULL;
 675         gss_mech_put(gss_auth->mech);
 676
 677         kfree(gss_auth);
 678         module_put(THIS_MODULE);
 679 }
 680
 681 /* gss_destroy_cred (and gss_destroy_ctx) are used to clean up after failure
 682  * to create a new cred or context, so they check that things have been
 683  * allocated before freeing them. */
 684 static void
 685 gss_destroy_ctx(struct gss_cl_ctx *ctx)
 686 {
 687         dprintk("RPC:       gss_destroy_ctx\n");
 688
 689         if (ctx->gc_gss_ctx)
 690                 gss_delete_sec_context(&ctx->gc_gss_ctx);
 691
 692         kfree(ctx->gc_wire_ctx.data);
 693         kfree(ctx);
 694 }
 695
 696 static void
 697 gss_free_cred(struct gss_cred *gss_cred)
 698 {
 699         dprintk("RPC:       gss_free_cred %p\n", gss_cred);
 700         if (gss_cred->gc_ctx)
 701                 gss_put_ctx(gss_cred->gc_ctx);
 702         kfree(gss_cred);
 703 }
 704
 705 static void
 706 gss_free_cred_callback(struct rcu_head *head)
 707 {
 708         struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu);
 709         gss_free_cred(gss_cred);
 710 }
 711
 712 static void
 713 gss_destroy_cred(struct rpc_cred *cred)
 714 {
 715         call_rcu(&cred->cr_rcu, gss_free_cred_callback);
 716 }
 717
 718 /*
 719  * Lookup RPCSEC_GSS cred for the current process
 720  */
 721 static struct rpc_cred *
 722 gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 723 {
 724         return rpcauth_lookup_credcache(auth, acred, flags);
 725 }
 726
 727 static struct rpc_cred *
 728 gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 729 {
 730         struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
 731         struct gss_cred *cred = NULL;
 732         int err = -ENOMEM;
 733
 734         dprintk("RPC:       gss_create_cred for uid %d, flavor %d\n",
 735                 acred->uid, auth->au_flavor);
 736
 737         if (!(cred = kzalloc(sizeof(*cred), GFP_KERNEL)))
 738                 goto out_err;
 739
 740         rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops);
 741         /*
 742          * Note: in order to force a call to call_refresh(), we deliberately
 743          * fail to flag the credential as RPCAUTH_CRED_UPTODATE.
 744          */
 745         cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW;
 746         cred->gc_service = gss_auth->service;
 747         return &cred->gc_base;
 748
 749 out_err:
 750         dprintk("RPC:       gss_create_cred failed with error %d\n", err);
 751         return ERR_PTR(err);
 752 }
 753
 754 static int
 755 gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred)
 756 {
 757         struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
 758         struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base);
 759         int err;
 760
 761         do {
 762                 err = gss_create_upcall(gss_auth, gss_cred);
 763         } while (err == -EAGAIN);
 764         return err;
 765 }
 766
 767 static int
 768 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags)
 769 {
 770         struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
 771
 772         /*
 773          * If the searchflags have set RPCAUTH_LOOKUP_NEW, then
 774          * we don't really care if the credential has expired or not,
 775          * since the caller should be prepared to reinitialise it.
 776          */
 777         if ((flags & RPCAUTH_LOOKUP_NEW) && test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags))
 778                 goto out;
 779         /* Don't match with creds that have expired. */
 780         if (gss_cred->gc_ctx && time_after(jiffies, gss_cred->gc_ctx->gc_expiry))
 781                 return 0;
 782 out:
 783         return (rc->cr_uid == acred->uid);
 784 }
 785
 786 /*
 787 * Marshal credentials.
 788 * Maybe we should keep a cached credential for performance reasons.
 789 */
 790 static __be32 *
 791 gss_marshal(struct rpc_task *task, __be32 *p)
 792 {
 793         struct rpc_cred *cred = task->tk_msg.rpc_cred;
 794         struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
 795                                                  gc_base);
 796         struct gss_cl_ctx       *ctx = gss_cred_get_ctx(cred);
 797         __be32          *cred_len;
 798         struct rpc_rqst *req = task->tk_rqstp;
 799         u32             maj_stat = 0;
 800         struct xdr_netobj mic;
 801         struct kvec     iov;
 802         struct xdr_buf  verf_buf;
 803
 804         dprintk("RPC: %5u gss_marshal\n", task->tk_pid);
 805
 806         *p++ = htonl(RPC_AUTH_GSS);
 807         cred_len = p++;
 808
 809         spin_lock(&ctx->gc_seq_lock);
 810         req->rq_seqno = ctx->gc_seq++;
 811         spin_unlock(&ctx->gc_seq_lock);
 812
 813         *p++ = htonl((u32) RPC_GSS_VERSION);
 814         *p++ = htonl((u32) ctx->gc_proc);
 815         *p++ = htonl((u32) req->rq_seqno);
 816         *p++ = htonl((u32) gss_cred->gc_service);
 817         p = xdr_encode_netobj(p, &ctx->gc_wire_ctx);
 818         *cred_len = htonl((p - (cred_len + 1)) << 2);
 819
 820         /* We compute the checksum for the verifier over the xdr-encoded bytes
 821          * starting with the xid and ending at the end of the credential: */
 822         iov.iov_base = xprt_skip_transport_header(task->tk_xprt,
 823                                         req->rq_snd_buf.head[0].iov_base);
 824         iov.iov_len = (u8 *)p - (u8 *)iov.iov_base;
 825         xdr_buf_from_iov(&iov, &verf_buf);
 826
 827         /* set verifier flavor*/
 828         *p++ = htonl(RPC_AUTH_GSS);
 829
 830         mic.data = (u8 *)(p + 1);
 831         maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
 832         if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
 833                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 834         } else if (maj_stat != 0) {
 835                 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat);
 836                 goto out_put_ctx;
 837         }
 838         p = xdr_encode_opaque(p, NULL, mic.len);
 839         gss_put_ctx(ctx);
 840         return p;
 841 out_put_ctx:
 842         gss_put_ctx(ctx);
 843         return NULL;
 844 }
 845
 846 /*
 847 * Refresh credentials. XXX - finish
 848 */
 849 static int
 850 gss_refresh(struct rpc_task *task)
 851 {
 852
 853         if (!gss_cred_is_uptodate_ctx(task->tk_msg.rpc_cred))
 854                 return gss_refresh_upcall(task);
 855         return 0;
 856 }
 857
 858 static __be32 *
 859 gss_validate(struct rpc_task *task, __be32 *p)
 860 {
 861         struct rpc_cred *cred = task->tk_msg.rpc_cred;
 862         struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
 863         __be32          seq;
 864         struct kvec     iov;
 865         struct xdr_buf  verf_buf;
 866         struct xdr_netobj mic;
 867         u32             flav,len;
 868         u32             maj_stat;
 869
 870         dprintk("RPC: %5u gss_validate\n", task->tk_pid);
 871
 872         flav = ntohl(*p++);
 873         if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE)
 874                 goto out_bad;
 875         if (flav != RPC_AUTH_GSS)
 876                 goto out_bad;
 877         seq = htonl(task->tk_rqstp->rq_seqno);
 878         iov.iov_base = &seq;
 879         iov.iov_len = sizeof(seq);
 880         xdr_buf_from_iov(&iov, &verf_buf);
 881         mic.data = (u8 *)p;
 882         mic.len = len;
 883
 884         maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
 885         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
 886                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 887         if (maj_stat)
 888                 goto out_bad;
 889         /* We leave it to unwrap to calculate au_rslack. For now we just
 890          * calculate the length of the verifier: */
 891         task->tk_auth->au_verfsize = XDR_QUADLEN(len) + 2;
 892         gss_put_ctx(ctx);
 893         dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n",
 894                         task->tk_pid);
 895         return p + XDR_QUADLEN(len);
 896 out_bad:
 897         gss_put_ctx(ctx);
 898         dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid);
 899         return NULL;
 900 }
 901
 902 static inline int
 903 gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 904                 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj)
 905 {
 906         struct xdr_buf  *snd_buf = &rqstp->rq_snd_buf;
 907         struct xdr_buf  integ_buf;
 908         __be32          *integ_len = NULL;
 909         struct xdr_netobj mic;
 910         u32             offset;
 911         __be32          *q;
 912         struct kvec     *iov;
 913         u32             maj_stat = 0;
 914         int             status = -EIO;
 915
 916         integ_len = p++;
 917         offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
 918         *p++ = htonl(rqstp->rq_seqno);
 919
 920         status = encode(rqstp, p, obj);
 921         if (status)
 922                 return status;
 923
 924         if (xdr_buf_subsegment(snd_buf, &integ_buf,
 925                                 offset, snd_buf->len - offset))
 926                 return status;
 927         *integ_len = htonl(integ_buf.len);
 928
 929         /* guess whether we're in the head or the tail: */
 930         if (snd_buf->page_len || snd_buf->tail[0].iov_len)
 931                 iov = snd_buf->tail;
 932         else
 933                 iov = snd_buf->head;
 934         p = iov->iov_base + iov->iov_len;
 935         mic.data = (u8 *)(p + 1);
 936
 937         maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
 938         status = -EIO; /* XXX? */
 939         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
 940                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 941         else if (maj_stat)
 942                 return status;
 943         q = xdr_encode_opaque(p, NULL, mic.len);
 944
 945         offset = (u8 *)q - (u8 *)p;
 946         iov->iov_len += offset;
 947         snd_buf->len += offset;
 948         return 0;
 949 }
 950
 951 static void
 952 priv_release_snd_buf(struct rpc_rqst *rqstp)
 953 {
 954         int i;
 955
 956         for (i=0; i < rqstp->rq_enc_pages_num; i++)
 957                 __free_page(rqstp->rq_enc_pages[i]);
 958         kfree(rqstp->rq_enc_pages);
 959 }
 960
 961 static int
 962 alloc_enc_pages(struct rpc_rqst *rqstp)
 963 {
 964         struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
 965         int first, last, i;
 966
 967         if (snd_buf->page_len == 0) {
 968                 rqstp->rq_enc_pages_num = 0;
 969                 return 0;
 970         }
 971
 972         first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
 973         last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT;
 974         rqstp->rq_enc_pages_num = last - first + 1 + 1;
 975         rqstp->rq_enc_pages
 976                 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *),
 977                                 GFP_NOFS);
 978         if (!rqstp->rq_enc_pages)
 979                 goto out;
 980         for (i=0; i < rqstp->rq_enc_pages_num; i++) {
 981                 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS);
 982                 if (rqstp->rq_enc_pages[i] == NULL)
 983                         goto out_free;
 984         }
 985         rqstp->rq_release_snd_buf = priv_release_snd_buf;
 986         return 0;
 987 out_free:
 988         for (i--; i >= 0; i--) {
 989                 __free_page(rqstp->rq_enc_pages[i]);
 990         }
 991 out:
 992         return -EAGAIN;
 993 }
 994
 995 static inline int
 996 gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 997                 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj)
 998 {
 999         struct xdr_buf  *snd_buf = &rqstp->rq_snd_buf;
1000         u32             offset;
1001         u32             maj_stat;
1002         int             status;
1003         __be32          *opaque_len;
1004         struct page     **inpages;
1005         int             first;
1006         int             pad;
1007         struct kvec     *iov;
1008         char            *tmp;
1009
1010         opaque_len = p++;
1011         offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
1012         *p++ = htonl(rqstp->rq_seqno);
1013
1014         status = encode(rqstp, p, obj);
1015         if (status)
1016                 return status;
1017
1018         status = alloc_enc_pages(rqstp);
1019         if (status)
1020                 return status;
1021         first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
1022         inpages = snd_buf->pages + first;
1023         snd_buf->pages = rqstp->rq_enc_pages;
1024         snd_buf->page_base -= first << PAGE_CACHE_SHIFT;
1025         /* Give the tail its own page, in case we need extra space in the
1026          * head when wrapping: */
1027         if (snd_buf->page_len || snd_buf->tail[0].iov_len) {
1028                 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]);
1029                 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len);
1030                 snd_buf->tail[0].iov_base = tmp;
1031         }
1032         maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages);
1033         /* RPC_SLACK_SPACE should prevent this ever happening: */
1034         BUG_ON(snd_buf->len > snd_buf->buflen);
1035         status = -EIO;
1036         /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was
1037          * done anyway, so it's safe to put the request on the wire: */
1038         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1039                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1040         else if (maj_stat)
1041                 return status;
1042
1043         *opaque_len = htonl(snd_buf->len - offset);
1044         /* guess whether we're in the head or the tail: */
1045         if (snd_buf->page_len || snd_buf->tail[0].iov_len)
1046                 iov = snd_buf->tail;
1047         else
1048                 iov = snd_buf->head;
1049         p = iov->iov_base + iov->iov_len;
1050         pad = 3 - ((snd_buf->len - offset - 1) & 3);
1051         memset(p, 0, pad);
1052         iov->iov_len += pad;
1053         snd_buf->len += pad;
1054
1055         return 0;
1056 }
1057
1058 static int
1059 gss_wrap_req(struct rpc_task *task,
1060              kxdrproc_t encode, void *rqstp, __be32 *p, void *obj)
1061 {
1062         struct rpc_cred *cred = task->tk_msg.rpc_cred;
1063         struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1064                         gc_base);
1065         struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1066         int             status = -EIO;
1067
1068         dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid);
1069         if (ctx->gc_proc != RPC_GSS_PROC_DATA) {
1070                 /* The spec seems a little ambiguous here, but I think that not
1071                  * wrapping context destruction requests makes the most sense.
1072                  */
1073                 status = encode(rqstp, p, obj);
1074                 goto out;
1075         }
1076         switch (gss_cred->gc_service) {
1077                 case RPC_GSS_SVC_NONE:
1078                         status = encode(rqstp, p, obj);
1079                         break;
1080                 case RPC_GSS_SVC_INTEGRITY:
1081                         status = gss_wrap_req_integ(cred, ctx, encode,
1082                                                                 rqstp, p, obj);
1083                         break;
1084                 case RPC_GSS_SVC_PRIVACY:
1085                         status = gss_wrap_req_priv(cred, ctx, encode,
1086                                         rqstp, p, obj);
1087                         break;
1088         }
1089 out:
1090         gss_put_ctx(ctx);
1091         dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status);
1092         return status;
1093 }
1094
1095 static inline int
1096 gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1097                 struct rpc_rqst *rqstp, __be32 **p)
1098 {
1099         struct xdr_buf  *rcv_buf = &rqstp->rq_rcv_buf;
1100         struct xdr_buf integ_buf;
1101         struct xdr_netobj mic;
1102         u32 data_offset, mic_offset;
1103         u32 integ_len;
1104         u32 maj_stat;
1105         int status = -EIO;
1106
1107         integ_len = ntohl(*(*p)++);
1108         if (integ_len & 3)
1109                 return status;
1110         data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
1111         mic_offset = integ_len + data_offset;
1112         if (mic_offset > rcv_buf->len)
1113                 return status;
1114         if (ntohl(*(*p)++) != rqstp->rq_seqno)
1115                 return status;
1116
1117         if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset,
1118                                 mic_offset - data_offset))
1119                 return status;
1120
1121         if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset))
1122                 return status;
1123
1124         maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
1125         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1126                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1127         if (maj_stat != GSS_S_COMPLETE)
1128                 return status;
1129         return 0;
1130 }
1131
1132 static inline int
1133 gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
1134                 struct rpc_rqst *rqstp, __be32 **p)
1135 {
1136         struct xdr_buf  *rcv_buf = &rqstp->rq_rcv_buf;
1137         u32 offset;
1138         u32 opaque_len;
1139         u32 maj_stat;
1140         int status = -EIO;
1141
1142         opaque_len = ntohl(*(*p)++);
1143         offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
1144         if (offset + opaque_len > rcv_buf->len)
1145                 return status;
1146         /* remove padding: */
1147         rcv_buf->len = offset + opaque_len;
1148
1149         maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf);
1150         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
1151                 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
1152         if (maj_stat != GSS_S_COMPLETE)
1153                 return status;
1154         if (ntohl(*(*p)++) != rqstp->rq_seqno)
1155                 return status;
1156
1157         return 0;
1158 }
1159
1160
1161 static int
1162 gss_unwrap_resp(struct rpc_task *task,
1163                 kxdrproc_t decode, void *rqstp, __be32 *p, void *obj)
1164 {
1165         struct rpc_cred *cred = task->tk_msg.rpc_cred;
1166         struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
1167                         gc_base);
1168         struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
1169         __be32          *savedp = p;
1170         struct kvec     *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head;
1171         int             savedlen = head->iov_len;
1172         int             status = -EIO;
1173
1174         if (ctx->gc_proc != RPC_GSS_PROC_DATA)
1175                 goto out_decode;
1176         switch (gss_cred->gc_service) {
1177                 case RPC_GSS_SVC_NONE:
1178                         break;
1179                 case RPC_GSS_SVC_INTEGRITY:
1180                         status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p);
1181                         if (status)
1182                                 goto out;
1183                         break;
1184                 case RPC_GSS_SVC_PRIVACY:
1185                         status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p);
1186                         if (status)
1187                                 goto out;
1188                         break;
1189         }
1190         /* take into account extra slack for integrity and privacy cases: */
1191         task->tk_auth->au_rslack = task->tk_auth->au_verfsize + (p - savedp)
1192                                                 + (savedlen - head->iov_len);
1193 out_decode:
1194         status = decode(rqstp, p, obj);
1195 out:
1196         gss_put_ctx(ctx);
1197         dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid,
1198                         status);
1199         return status;
1200 }
1201
1202 static const struct rpc_authops authgss_ops = {
1203         .owner          = THIS_MODULE,
1204         .au_flavor      = RPC_AUTH_GSS,
1205 #ifdef RPC_DEBUG
1206         .au_name        = "RPCSEC_GSS",
1207 #endif
1208         .create         = gss_create,
1209         .destroy        = gss_destroy,
1210         .lookup_cred    = gss_lookup_cred,
1211         .crcreate       = gss_create_cred
1212 };
1213
1214 static const struct rpc_credops gss_credops = {
1215         .cr_name        = "AUTH_GSS",
1216         .crdestroy      = gss_destroy_cred,
1217         .cr_init        = gss_cred_init,
1218         .crmatch        = gss_match,
1219         .crmarshal      = gss_marshal,
1220         .crrefresh      = gss_refresh,
1221         .crvalidate     = gss_validate,
1222         .crwrap_req     = gss_wrap_req,
1223         .crunwrap_resp  = gss_unwrap_resp,
1224 };
1225
1226 static struct rpc_pipe_ops gss_upcall_ops = {
1227         .upcall         = gss_pipe_upcall,
1228         .downcall       = gss_pipe_downcall,
1229         .destroy_msg    = gss_pipe_destroy_msg,
1230         .release_pipe   = gss_pipe_release,
1231 };
1232
1233 /*
1234  * Initialize RPCSEC_GSS module
1235  */
1236 static int __init init_rpcsec_gss(void)
1237 {
1238         int err = 0;
1239
1240         err = rpcauth_register(&authgss_ops);
1241         if (err)
1242                 goto out;
1243         err = gss_svc_init();
1244         if (err)
1245                 goto out_unregister;
1246         return 0;
1247 out_unregister:
1248         rpcauth_unregister(&authgss_ops);
1249 out:
1250         return err;
1251 }
1252
1253 static void __exit exit_rpcsec_gss(void)
1254 {
1255         gss_svc_shutdown();
1256         rpcauth_unregister(&authgss_ops);
1257 }
1258
1259 MODULE_LICENSE("GPL");
1260 module_init(init_rpcsec_gss)
1261 module_exit(exit_rpcsec_gss)