auth_gss.c revision 1f4c86c0be9064ab4eebd9e67c84606c1cfeec4b
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 55static const struct rpc_authops authgss_ops; 56 57static const struct rpc_credops gss_credops; 58static const struct rpc_credops gss_nullops; 59 60#ifdef RPC_DEBUG 61# define RPCDBG_FACILITY RPCDBG_AUTH 62#endif 63 64#define GSS_CRED_SLACK (RPC_MAX_AUTH_SIZE * 2) 65/* length of a krb5 verifier (48), plus data added before arguments when 66 * using integrity (two 4-byte integers): */ 67#define GSS_VERF_SLACK 100 68 69struct gss_auth { 70 struct kref kref; 71 struct rpc_auth rpc_auth; 72 struct gss_api_mech *mech; 73 enum rpc_gss_svc service; 74 struct rpc_clnt *client; 75 /* 76 * There are two upcall pipes; dentry[1], named "gssd", is used 77 * for the new text-based upcall; dentry[0] is named after the 78 * mechanism (for example, "krb5") and exists for 79 * backwards-compatibility with older gssd's. 80 */ 81 struct dentry *dentry[2]; 82}; 83 84/* pipe_version >= 0 if and only if someone has a pipe open. */ 85static int pipe_version = -1; 86static atomic_t pipe_users = ATOMIC_INIT(0); 87static DEFINE_SPINLOCK(pipe_version_lock); 88static struct rpc_wait_queue pipe_version_rpc_waitqueue; 89static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue); 90 91static void gss_free_ctx(struct gss_cl_ctx *); 92static const struct rpc_pipe_ops gss_upcall_ops_v0; 93static const struct rpc_pipe_ops gss_upcall_ops_v1; 94 95static inline struct gss_cl_ctx * 96gss_get_ctx(struct gss_cl_ctx *ctx) 97{ 98 atomic_inc(&ctx->count); 99 return ctx; 100} 101 102static inline void 103gss_put_ctx(struct gss_cl_ctx *ctx) 104{ 105 if (atomic_dec_and_test(&ctx->count)) 106 gss_free_ctx(ctx); 107} 108 109/* gss_cred_set_ctx: 110 * called by gss_upcall_callback and gss_create_upcall in order 111 * to set the gss context. The actual exchange of an old context 112 * and a new one is protected by the inode->i_lock. 113 */ 114static void 115gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) 116{ 117 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 118 119 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 120 return; 121 gss_get_ctx(ctx); 122 rcu_assign_pointer(gss_cred->gc_ctx, ctx); 123 set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 124 smp_mb__before_clear_bit(); 125 clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags); 126} 127 128static const void * 129simple_get_bytes(const void *p, const void *end, void *res, size_t len) 130{ 131 const void *q = (const void *)((const char *)p + len); 132 if (unlikely(q > end || q < p)) 133 return ERR_PTR(-EFAULT); 134 memcpy(res, p, len); 135 return q; 136} 137 138static inline const void * 139simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) 140{ 141 const void *q; 142 unsigned int len; 143 144 p = simple_get_bytes(p, end, &len, sizeof(len)); 145 if (IS_ERR(p)) 146 return p; 147 q = (const void *)((const char *)p + len); 148 if (unlikely(q > end || q < p)) 149 return ERR_PTR(-EFAULT); 150 dest->data = kmemdup(p, len, GFP_NOFS); 151 if (unlikely(dest->data == NULL)) 152 return ERR_PTR(-ENOMEM); 153 dest->len = len; 154 return q; 155} 156 157static struct gss_cl_ctx * 158gss_cred_get_ctx(struct rpc_cred *cred) 159{ 160 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 161 struct gss_cl_ctx *ctx = NULL; 162 163 rcu_read_lock(); 164 if (gss_cred->gc_ctx) 165 ctx = gss_get_ctx(gss_cred->gc_ctx); 166 rcu_read_unlock(); 167 return ctx; 168} 169 170static struct gss_cl_ctx * 171gss_alloc_context(void) 172{ 173 struct gss_cl_ctx *ctx; 174 175 ctx = kzalloc(sizeof(*ctx), GFP_NOFS); 176 if (ctx != NULL) { 177 ctx->gc_proc = RPC_GSS_PROC_DATA; 178 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ 179 spin_lock_init(&ctx->gc_seq_lock); 180 atomic_set(&ctx->count,1); 181 } 182 return ctx; 183} 184 185#define GSSD_MIN_TIMEOUT (60 * 60) 186static const void * 187gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) 188{ 189 const void *q; 190 unsigned int seclen; 191 unsigned int timeout; 192 u32 window_size; 193 int ret; 194 195 /* First unsigned int gives the lifetime (in seconds) of the cred */ 196 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 197 if (IS_ERR(p)) 198 goto err; 199 if (timeout == 0) 200 timeout = GSSD_MIN_TIMEOUT; 201 ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4; 202 /* Sequence number window. Determines the maximum number of simultaneous requests */ 203 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 204 if (IS_ERR(p)) 205 goto err; 206 ctx->gc_win = window_size; 207 /* gssd signals an error by passing ctx->gc_win = 0: */ 208 if (ctx->gc_win == 0) { 209 /* 210 * in which case, p points to an error code. Anything other 211 * than -EKEYEXPIRED gets converted to -EACCES. 212 */ 213 p = simple_get_bytes(p, end, &ret, sizeof(ret)); 214 if (!IS_ERR(p)) 215 p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) : 216 ERR_PTR(-EACCES); 217 goto err; 218 } 219 /* copy the opaque wire context */ 220 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 221 if (IS_ERR(p)) 222 goto err; 223 /* import the opaque security context */ 224 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 225 if (IS_ERR(p)) 226 goto err; 227 q = (const void *)((const char *)p + seclen); 228 if (unlikely(q > end || q < p)) { 229 p = ERR_PTR(-EFAULT); 230 goto err; 231 } 232 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, GFP_NOFS); 233 if (ret < 0) { 234 p = ERR_PTR(ret); 235 goto err; 236 } 237 return q; 238err: 239 dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p)); 240 return p; 241} 242 243#define UPCALL_BUF_LEN 128 244 245struct gss_upcall_msg { 246 atomic_t count; 247 uid_t uid; 248 struct rpc_pipe_msg msg; 249 struct list_head list; 250 struct gss_auth *auth; 251 struct rpc_inode *inode; 252 struct rpc_wait_queue rpc_waitqueue; 253 wait_queue_head_t waitqueue; 254 struct gss_cl_ctx *ctx; 255 char databuf[UPCALL_BUF_LEN]; 256}; 257 258static int get_pipe_version(void) 259{ 260 int ret; 261 262 spin_lock(&pipe_version_lock); 263 if (pipe_version >= 0) { 264 atomic_inc(&pipe_users); 265 ret = pipe_version; 266 } else 267 ret = -EAGAIN; 268 spin_unlock(&pipe_version_lock); 269 return ret; 270} 271 272static void put_pipe_version(void) 273{ 274 if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) { 275 pipe_version = -1; 276 spin_unlock(&pipe_version_lock); 277 } 278} 279 280static void 281gss_release_msg(struct gss_upcall_msg *gss_msg) 282{ 283 if (!atomic_dec_and_test(&gss_msg->count)) 284 return; 285 put_pipe_version(); 286 BUG_ON(!list_empty(&gss_msg->list)); 287 if (gss_msg->ctx != NULL) 288 gss_put_ctx(gss_msg->ctx); 289 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue); 290 kfree(gss_msg); 291} 292 293static struct gss_upcall_msg * 294__gss_find_upcall(struct rpc_inode *rpci, uid_t uid) 295{ 296 struct gss_upcall_msg *pos; 297 list_for_each_entry(pos, &rpci->in_downcall, list) { 298 if (pos->uid != uid) 299 continue; 300 atomic_inc(&pos->count); 301 dprintk("RPC: gss_find_upcall found msg %p\n", pos); 302 return pos; 303 } 304 dprintk("RPC: gss_find_upcall found nothing\n"); 305 return NULL; 306} 307 308/* Try to add an upcall to the pipefs queue. 309 * If an upcall owned by our uid already exists, then we return a reference 310 * to that upcall instead of adding the new upcall. 311 */ 312static inline struct gss_upcall_msg * 313gss_add_msg(struct gss_upcall_msg *gss_msg) 314{ 315 struct rpc_inode *rpci = gss_msg->inode; 316 struct inode *inode = &rpci->vfs_inode; 317 struct gss_upcall_msg *old; 318 319 spin_lock(&inode->i_lock); 320 old = __gss_find_upcall(rpci, gss_msg->uid); 321 if (old == NULL) { 322 atomic_inc(&gss_msg->count); 323 list_add(&gss_msg->list, &rpci->in_downcall); 324 } else 325 gss_msg = old; 326 spin_unlock(&inode->i_lock); 327 return gss_msg; 328} 329 330static void 331__gss_unhash_msg(struct gss_upcall_msg *gss_msg) 332{ 333 list_del_init(&gss_msg->list); 334 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 335 wake_up_all(&gss_msg->waitqueue); 336 atomic_dec(&gss_msg->count); 337} 338 339static void 340gss_unhash_msg(struct gss_upcall_msg *gss_msg) 341{ 342 struct inode *inode = &gss_msg->inode->vfs_inode; 343 344 if (list_empty(&gss_msg->list)) 345 return; 346 spin_lock(&inode->i_lock); 347 if (!list_empty(&gss_msg->list)) 348 __gss_unhash_msg(gss_msg); 349 spin_unlock(&inode->i_lock); 350} 351 352static void 353gss_upcall_callback(struct rpc_task *task) 354{ 355 struct gss_cred *gss_cred = container_of(task->tk_msg.rpc_cred, 356 struct gss_cred, gc_base); 357 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 358 struct inode *inode = &gss_msg->inode->vfs_inode; 359 360 spin_lock(&inode->i_lock); 361 if (gss_msg->ctx) 362 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_msg->ctx); 363 else 364 task->tk_status = gss_msg->msg.errno; 365 gss_cred->gc_upcall = NULL; 366 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 367 spin_unlock(&inode->i_lock); 368 gss_release_msg(gss_msg); 369} 370 371static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 372{ 373 gss_msg->msg.data = &gss_msg->uid; 374 gss_msg->msg.len = sizeof(gss_msg->uid); 375} 376 377static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 378 struct rpc_clnt *clnt, int machine_cred) 379{ 380 struct gss_api_mech *mech = gss_msg->auth->mech; 381 char *p = gss_msg->databuf; 382 int len = 0; 383 384 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ", 385 mech->gm_name, 386 gss_msg->uid); 387 p += gss_msg->msg.len; 388 if (clnt->cl_principal) { 389 len = sprintf(p, "target=%s ", clnt->cl_principal); 390 p += len; 391 gss_msg->msg.len += len; 392 } 393 if (machine_cred) { 394 len = sprintf(p, "service=* "); 395 p += len; 396 gss_msg->msg.len += len; 397 } else if (!strcmp(clnt->cl_program->name, "nfs4_cb")) { 398 len = sprintf(p, "service=nfs "); 399 p += len; 400 gss_msg->msg.len += len; 401 } 402 if (mech->gm_upcall_enctypes) { 403 len = sprintf(p, mech->gm_upcall_enctypes); 404 p += len; 405 gss_msg->msg.len += len; 406 } 407 len = sprintf(p, "\n"); 408 gss_msg->msg.len += len; 409 410 gss_msg->msg.data = gss_msg->databuf; 411 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); 412} 413 414static void gss_encode_msg(struct gss_upcall_msg *gss_msg, 415 struct rpc_clnt *clnt, int machine_cred) 416{ 417 if (pipe_version == 0) 418 gss_encode_v0_msg(gss_msg); 419 else /* pipe_version == 1 */ 420 gss_encode_v1_msg(gss_msg, clnt, machine_cred); 421} 422 423static inline struct gss_upcall_msg * 424gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid, struct rpc_clnt *clnt, 425 int machine_cred) 426{ 427 struct gss_upcall_msg *gss_msg; 428 int vers; 429 430 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 431 if (gss_msg == NULL) 432 return ERR_PTR(-ENOMEM); 433 vers = get_pipe_version(); 434 if (vers < 0) { 435 kfree(gss_msg); 436 return ERR_PTR(vers); 437 } 438 gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode); 439 INIT_LIST_HEAD(&gss_msg->list); 440 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 441 init_waitqueue_head(&gss_msg->waitqueue); 442 atomic_set(&gss_msg->count, 1); 443 gss_msg->uid = uid; 444 gss_msg->auth = gss_auth; 445 gss_encode_msg(gss_msg, clnt, machine_cred); 446 return gss_msg; 447} 448 449static struct gss_upcall_msg * 450gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 451{ 452 struct gss_cred *gss_cred = container_of(cred, 453 struct gss_cred, gc_base); 454 struct gss_upcall_msg *gss_new, *gss_msg; 455 uid_t uid = cred->cr_uid; 456 457 gss_new = gss_alloc_msg(gss_auth, uid, clnt, gss_cred->gc_machine_cred); 458 if (IS_ERR(gss_new)) 459 return gss_new; 460 gss_msg = gss_add_msg(gss_new); 461 if (gss_msg == gss_new) { 462 struct inode *inode = &gss_new->inode->vfs_inode; 463 int res = rpc_queue_upcall(inode, &gss_new->msg); 464 if (res) { 465 gss_unhash_msg(gss_new); 466 gss_msg = ERR_PTR(res); 467 } 468 } else 469 gss_release_msg(gss_new); 470 return gss_msg; 471} 472 473static void warn_gssd(void) 474{ 475 static unsigned long ratelimit; 476 unsigned long now = jiffies; 477 478 if (time_after(now, ratelimit)) { 479 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 480 "Please check user daemon is running.\n"); 481 ratelimit = now + 15*HZ; 482 } 483} 484 485static inline int 486gss_refresh_upcall(struct rpc_task *task) 487{ 488 struct rpc_cred *cred = task->tk_msg.rpc_cred; 489 struct gss_auth *gss_auth = container_of(cred->cr_auth, 490 struct gss_auth, rpc_auth); 491 struct gss_cred *gss_cred = container_of(cred, 492 struct gss_cred, gc_base); 493 struct gss_upcall_msg *gss_msg; 494 struct inode *inode; 495 int err = 0; 496 497 dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid, 498 cred->cr_uid); 499 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 500 if (PTR_ERR(gss_msg) == -EAGAIN) { 501 /* XXX: warning on the first, under the assumption we 502 * shouldn't normally hit this case on a refresh. */ 503 warn_gssd(); 504 task->tk_timeout = 15*HZ; 505 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 506 return 0; 507 } 508 if (IS_ERR(gss_msg)) { 509 err = PTR_ERR(gss_msg); 510 goto out; 511 } 512 inode = &gss_msg->inode->vfs_inode; 513 spin_lock(&inode->i_lock); 514 if (gss_cred->gc_upcall != NULL) 515 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 516 else if (gss_msg->ctx != NULL) { 517 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_msg->ctx); 518 gss_cred->gc_upcall = NULL; 519 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 520 } else if (gss_msg->msg.errno >= 0) { 521 task->tk_timeout = 0; 522 gss_cred->gc_upcall = gss_msg; 523 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 524 atomic_inc(&gss_msg->count); 525 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 526 } else 527 err = gss_msg->msg.errno; 528 spin_unlock(&inode->i_lock); 529 gss_release_msg(gss_msg); 530out: 531 dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n", 532 task->tk_pid, cred->cr_uid, err); 533 return err; 534} 535 536static inline int 537gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 538{ 539 struct inode *inode; 540 struct rpc_cred *cred = &gss_cred->gc_base; 541 struct gss_upcall_msg *gss_msg; 542 DEFINE_WAIT(wait); 543 int err = 0; 544 545 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); 546retry: 547 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 548 if (PTR_ERR(gss_msg) == -EAGAIN) { 549 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 550 pipe_version >= 0, 15*HZ); 551 if (err) 552 goto out; 553 if (pipe_version < 0) 554 warn_gssd(); 555 goto retry; 556 } 557 if (IS_ERR(gss_msg)) { 558 err = PTR_ERR(gss_msg); 559 goto out; 560 } 561 inode = &gss_msg->inode->vfs_inode; 562 for (;;) { 563 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); 564 spin_lock(&inode->i_lock); 565 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 566 break; 567 } 568 spin_unlock(&inode->i_lock); 569 if (signalled()) { 570 err = -ERESTARTSYS; 571 goto out_intr; 572 } 573 schedule(); 574 } 575 if (gss_msg->ctx) 576 gss_cred_set_ctx(cred, gss_msg->ctx); 577 else 578 err = gss_msg->msg.errno; 579 spin_unlock(&inode->i_lock); 580out_intr: 581 finish_wait(&gss_msg->waitqueue, &wait); 582 gss_release_msg(gss_msg); 583out: 584 dprintk("RPC: gss_create_upcall for uid %u result %d\n", 585 cred->cr_uid, err); 586 return err; 587} 588 589static ssize_t 590gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, 591 char __user *dst, size_t buflen) 592{ 593 char *data = (char *)msg->data + msg->copied; 594 size_t mlen = min(msg->len, buflen); 595 unsigned long left; 596 597 left = copy_to_user(dst, data, mlen); 598 if (left == mlen) { 599 msg->errno = -EFAULT; 600 return -EFAULT; 601 } 602 603 mlen -= left; 604 msg->copied += mlen; 605 msg->errno = 0; 606 return mlen; 607} 608 609#define MSG_BUF_MAXSIZE 1024 610 611static ssize_t 612gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 613{ 614 const void *p, *end; 615 void *buf; 616 struct gss_upcall_msg *gss_msg; 617 struct inode *inode = filp->f_path.dentry->d_inode; 618 struct gss_cl_ctx *ctx; 619 uid_t uid; 620 ssize_t err = -EFBIG; 621 622 if (mlen > MSG_BUF_MAXSIZE) 623 goto out; 624 err = -ENOMEM; 625 buf = kmalloc(mlen, GFP_NOFS); 626 if (!buf) 627 goto out; 628 629 err = -EFAULT; 630 if (copy_from_user(buf, src, mlen)) 631 goto err; 632 633 end = (const void *)((char *)buf + mlen); 634 p = simple_get_bytes(buf, end, &uid, sizeof(uid)); 635 if (IS_ERR(p)) { 636 err = PTR_ERR(p); 637 goto err; 638 } 639 640 err = -ENOMEM; 641 ctx = gss_alloc_context(); 642 if (ctx == NULL) 643 goto err; 644 645 err = -ENOENT; 646 /* Find a matching upcall */ 647 spin_lock(&inode->i_lock); 648 gss_msg = __gss_find_upcall(RPC_I(inode), uid); 649 if (gss_msg == NULL) { 650 spin_unlock(&inode->i_lock); 651 goto err_put_ctx; 652 } 653 list_del_init(&gss_msg->list); 654 spin_unlock(&inode->i_lock); 655 656 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); 657 if (IS_ERR(p)) { 658 err = PTR_ERR(p); 659 switch (err) { 660 case -EACCES: 661 case -EKEYEXPIRED: 662 gss_msg->msg.errno = err; 663 err = mlen; 664 break; 665 case -EFAULT: 666 case -ENOMEM: 667 case -EINVAL: 668 case -ENOSYS: 669 gss_msg->msg.errno = -EAGAIN; 670 break; 671 default: 672 printk(KERN_CRIT "%s: bad return from " 673 "gss_fill_context: %zd\n", __func__, err); 674 BUG(); 675 } 676 goto err_release_msg; 677 } 678 gss_msg->ctx = gss_get_ctx(ctx); 679 err = mlen; 680 681err_release_msg: 682 spin_lock(&inode->i_lock); 683 __gss_unhash_msg(gss_msg); 684 spin_unlock(&inode->i_lock); 685 gss_release_msg(gss_msg); 686err_put_ctx: 687 gss_put_ctx(ctx); 688err: 689 kfree(buf); 690out: 691 dprintk("RPC: gss_pipe_downcall returning %Zd\n", err); 692 return err; 693} 694 695static int gss_pipe_open(struct inode *inode, int new_version) 696{ 697 int ret = 0; 698 699 spin_lock(&pipe_version_lock); 700 if (pipe_version < 0) { 701 /* First open of any gss pipe determines the version: */ 702 pipe_version = new_version; 703 rpc_wake_up(&pipe_version_rpc_waitqueue); 704 wake_up(&pipe_version_waitqueue); 705 } else if (pipe_version != new_version) { 706 /* Trying to open a pipe of a different version */ 707 ret = -EBUSY; 708 goto out; 709 } 710 atomic_inc(&pipe_users); 711out: 712 spin_unlock(&pipe_version_lock); 713 return ret; 714 715} 716 717static int gss_pipe_open_v0(struct inode *inode) 718{ 719 return gss_pipe_open(inode, 0); 720} 721 722static int gss_pipe_open_v1(struct inode *inode) 723{ 724 return gss_pipe_open(inode, 1); 725} 726 727static void 728gss_pipe_release(struct inode *inode) 729{ 730 struct rpc_inode *rpci = RPC_I(inode); 731 struct gss_upcall_msg *gss_msg; 732 733 spin_lock(&inode->i_lock); 734 while (!list_empty(&rpci->in_downcall)) { 735 736 gss_msg = list_entry(rpci->in_downcall.next, 737 struct gss_upcall_msg, list); 738 gss_msg->msg.errno = -EPIPE; 739 atomic_inc(&gss_msg->count); 740 __gss_unhash_msg(gss_msg); 741 spin_unlock(&inode->i_lock); 742 gss_release_msg(gss_msg); 743 spin_lock(&inode->i_lock); 744 } 745 spin_unlock(&inode->i_lock); 746 747 put_pipe_version(); 748} 749 750static void 751gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 752{ 753 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 754 755 if (msg->errno < 0) { 756 dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n", 757 gss_msg); 758 atomic_inc(&gss_msg->count); 759 gss_unhash_msg(gss_msg); 760 if (msg->errno == -ETIMEDOUT) 761 warn_gssd(); 762 gss_release_msg(gss_msg); 763 } 764} 765 766/* 767 * NOTE: we have the opportunity to use different 768 * parameters based on the input flavor (which must be a pseudoflavor) 769 */ 770static struct rpc_auth * 771gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 772{ 773 struct gss_auth *gss_auth; 774 struct rpc_auth * auth; 775 int err = -ENOMEM; /* XXX? */ 776 777 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 778 779 if (!try_module_get(THIS_MODULE)) 780 return ERR_PTR(err); 781 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 782 goto out_dec; 783 gss_auth->client = clnt; 784 err = -EINVAL; 785 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 786 if (!gss_auth->mech) { 787 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 788 __func__, flavor); 789 goto err_free; 790 } 791 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 792 if (gss_auth->service == 0) 793 goto err_put_mech; 794 auth = &gss_auth->rpc_auth; 795 auth->au_cslack = GSS_CRED_SLACK >> 2; 796 auth->au_rslack = GSS_VERF_SLACK >> 2; 797 auth->au_ops = &authgss_ops; 798 auth->au_flavor = flavor; 799 atomic_set(&auth->au_count, 1); 800 kref_init(&gss_auth->kref); 801 802 /* 803 * Note: if we created the old pipe first, then someone who 804 * examined the directory at the right moment might conclude 805 * that we supported only the old pipe. So we instead create 806 * the new pipe first. 807 */ 808 gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_path.dentry, 809 "gssd", 810 clnt, &gss_upcall_ops_v1, 811 RPC_PIPE_WAIT_FOR_OPEN); 812 if (IS_ERR(gss_auth->dentry[1])) { 813 err = PTR_ERR(gss_auth->dentry[1]); 814 goto err_put_mech; 815 } 816 817 gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_path.dentry, 818 gss_auth->mech->gm_name, 819 clnt, &gss_upcall_ops_v0, 820 RPC_PIPE_WAIT_FOR_OPEN); 821 if (IS_ERR(gss_auth->dentry[0])) { 822 err = PTR_ERR(gss_auth->dentry[0]); 823 goto err_unlink_pipe_1; 824 } 825 err = rpcauth_init_credcache(auth); 826 if (err) 827 goto err_unlink_pipe_0; 828 829 return auth; 830err_unlink_pipe_0: 831 rpc_unlink(gss_auth->dentry[0]); 832err_unlink_pipe_1: 833 rpc_unlink(gss_auth->dentry[1]); 834err_put_mech: 835 gss_mech_put(gss_auth->mech); 836err_free: 837 kfree(gss_auth); 838out_dec: 839 module_put(THIS_MODULE); 840 return ERR_PTR(err); 841} 842 843static void 844gss_free(struct gss_auth *gss_auth) 845{ 846 rpc_unlink(gss_auth->dentry[1]); 847 rpc_unlink(gss_auth->dentry[0]); 848 gss_mech_put(gss_auth->mech); 849 850 kfree(gss_auth); 851 module_put(THIS_MODULE); 852} 853 854static void 855gss_free_callback(struct kref *kref) 856{ 857 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 858 859 gss_free(gss_auth); 860} 861 862static void 863gss_destroy(struct rpc_auth *auth) 864{ 865 struct gss_auth *gss_auth; 866 867 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 868 auth, auth->au_flavor); 869 870 rpcauth_destroy_credcache(auth); 871 872 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 873 kref_put(&gss_auth->kref, gss_free_callback); 874} 875 876/* 877 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 878 * to the server with the GSS control procedure field set to 879 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 880 * all RPCSEC_GSS state associated with that context. 881 */ 882static int 883gss_destroying_context(struct rpc_cred *cred) 884{ 885 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 886 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 887 struct rpc_task *task; 888 889 if (gss_cred->gc_ctx == NULL || 890 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 891 return 0; 892 893 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 894 cred->cr_ops = &gss_nullops; 895 896 /* Take a reference to ensure the cred will be destroyed either 897 * by the RPC call or by the put_rpccred() below */ 898 get_rpccred(cred); 899 900 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 901 if (!IS_ERR(task)) 902 rpc_put_task(task); 903 904 put_rpccred(cred); 905 return 1; 906} 907 908/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 909 * to create a new cred or context, so they check that things have been 910 * allocated before freeing them. */ 911static void 912gss_do_free_ctx(struct gss_cl_ctx *ctx) 913{ 914 dprintk("RPC: gss_free_ctx\n"); 915 916 kfree(ctx->gc_wire_ctx.data); 917 kfree(ctx); 918} 919 920static void 921gss_free_ctx_callback(struct rcu_head *head) 922{ 923 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 924 gss_do_free_ctx(ctx); 925} 926 927static void 928gss_free_ctx(struct gss_cl_ctx *ctx) 929{ 930 struct gss_ctx *gc_gss_ctx; 931 932 gc_gss_ctx = rcu_dereference(ctx->gc_gss_ctx); 933 rcu_assign_pointer(ctx->gc_gss_ctx, NULL); 934 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 935 if (gc_gss_ctx) 936 gss_delete_sec_context(&gc_gss_ctx); 937} 938 939static void 940gss_free_cred(struct gss_cred *gss_cred) 941{ 942 dprintk("RPC: gss_free_cred %p\n", gss_cred); 943 kfree(gss_cred); 944} 945 946static void 947gss_free_cred_callback(struct rcu_head *head) 948{ 949 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 950 gss_free_cred(gss_cred); 951} 952 953static void 954gss_destroy_nullcred(struct rpc_cred *cred) 955{ 956 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 957 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 958 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 959 960 rcu_assign_pointer(gss_cred->gc_ctx, NULL); 961 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 962 if (ctx) 963 gss_put_ctx(ctx); 964 kref_put(&gss_auth->kref, gss_free_callback); 965} 966 967static void 968gss_destroy_cred(struct rpc_cred *cred) 969{ 970 971 if (gss_destroying_context(cred)) 972 return; 973 gss_destroy_nullcred(cred); 974} 975 976/* 977 * Lookup RPCSEC_GSS cred for the current process 978 */ 979static struct rpc_cred * 980gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 981{ 982 return rpcauth_lookup_credcache(auth, acred, flags); 983} 984 985static struct rpc_cred * 986gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 987{ 988 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 989 struct gss_cred *cred = NULL; 990 int err = -ENOMEM; 991 992 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 993 acred->uid, auth->au_flavor); 994 995 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 996 goto out_err; 997 998 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 999 /* 1000 * Note: in order to force a call to call_refresh(), we deliberately 1001 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 1002 */ 1003 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 1004 cred->gc_service = gss_auth->service; 1005 cred->gc_machine_cred = acred->machine_cred; 1006 kref_get(&gss_auth->kref); 1007 return &cred->gc_base; 1008 1009out_err: 1010 dprintk("RPC: gss_create_cred failed with error %d\n", err); 1011 return ERR_PTR(err); 1012} 1013 1014static int 1015gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1016{ 1017 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1018 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1019 int err; 1020 1021 do { 1022 err = gss_create_upcall(gss_auth, gss_cred); 1023 } while (err == -EAGAIN); 1024 return err; 1025} 1026 1027static int 1028gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1029{ 1030 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1031 1032 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1033 goto out; 1034 /* Don't match with creds that have expired. */ 1035 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1036 return 0; 1037 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1038 return 0; 1039out: 1040 if (acred->machine_cred != gss_cred->gc_machine_cred) 1041 return 0; 1042 return (rc->cr_uid == acred->uid); 1043} 1044 1045/* 1046* Marshal credentials. 1047* Maybe we should keep a cached credential for performance reasons. 1048*/ 1049static __be32 * 1050gss_marshal(struct rpc_task *task, __be32 *p) 1051{ 1052 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1053 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1054 gc_base); 1055 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1056 __be32 *cred_len; 1057 struct rpc_rqst *req = task->tk_rqstp; 1058 u32 maj_stat = 0; 1059 struct xdr_netobj mic; 1060 struct kvec iov; 1061 struct xdr_buf verf_buf; 1062 1063 dprintk("RPC: %5u gss_marshal\n", task->tk_pid); 1064 1065 *p++ = htonl(RPC_AUTH_GSS); 1066 cred_len = p++; 1067 1068 spin_lock(&ctx->gc_seq_lock); 1069 req->rq_seqno = ctx->gc_seq++; 1070 spin_unlock(&ctx->gc_seq_lock); 1071 1072 *p++ = htonl((u32) RPC_GSS_VERSION); 1073 *p++ = htonl((u32) ctx->gc_proc); 1074 *p++ = htonl((u32) req->rq_seqno); 1075 *p++ = htonl((u32) gss_cred->gc_service); 1076 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1077 *cred_len = htonl((p - (cred_len + 1)) << 2); 1078 1079 /* We compute the checksum for the verifier over the xdr-encoded bytes 1080 * starting with the xid and ending at the end of the credential: */ 1081 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 1082 req->rq_snd_buf.head[0].iov_base); 1083 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1084 xdr_buf_from_iov(&iov, &verf_buf); 1085 1086 /* set verifier flavor*/ 1087 *p++ = htonl(RPC_AUTH_GSS); 1088 1089 mic.data = (u8 *)(p + 1); 1090 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1091 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1092 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1093 } else if (maj_stat != 0) { 1094 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1095 goto out_put_ctx; 1096 } 1097 p = xdr_encode_opaque(p, NULL, mic.len); 1098 gss_put_ctx(ctx); 1099 return p; 1100out_put_ctx: 1101 gss_put_ctx(ctx); 1102 return NULL; 1103} 1104 1105static int gss_renew_cred(struct rpc_task *task) 1106{ 1107 struct rpc_cred *oldcred = task->tk_msg.rpc_cred; 1108 struct gss_cred *gss_cred = container_of(oldcred, 1109 struct gss_cred, 1110 gc_base); 1111 struct rpc_auth *auth = oldcred->cr_auth; 1112 struct auth_cred acred = { 1113 .uid = oldcred->cr_uid, 1114 .machine_cred = gss_cred->gc_machine_cred, 1115 }; 1116 struct rpc_cred *new; 1117 1118 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1119 if (IS_ERR(new)) 1120 return PTR_ERR(new); 1121 task->tk_msg.rpc_cred = new; 1122 put_rpccred(oldcred); 1123 return 0; 1124} 1125 1126/* 1127* Refresh credentials. XXX - finish 1128*/ 1129static int 1130gss_refresh(struct rpc_task *task) 1131{ 1132 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1133 int ret = 0; 1134 1135 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1136 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1137 ret = gss_renew_cred(task); 1138 if (ret < 0) 1139 goto out; 1140 cred = task->tk_msg.rpc_cred; 1141 } 1142 1143 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1144 ret = gss_refresh_upcall(task); 1145out: 1146 return ret; 1147} 1148 1149/* Dummy refresh routine: used only when destroying the context */ 1150static int 1151gss_refresh_null(struct rpc_task *task) 1152{ 1153 return -EACCES; 1154} 1155 1156static __be32 * 1157gss_validate(struct rpc_task *task, __be32 *p) 1158{ 1159 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1160 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1161 __be32 seq; 1162 struct kvec iov; 1163 struct xdr_buf verf_buf; 1164 struct xdr_netobj mic; 1165 u32 flav,len; 1166 u32 maj_stat; 1167 1168 dprintk("RPC: %5u gss_validate\n", task->tk_pid); 1169 1170 flav = ntohl(*p++); 1171 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1172 goto out_bad; 1173 if (flav != RPC_AUTH_GSS) 1174 goto out_bad; 1175 seq = htonl(task->tk_rqstp->rq_seqno); 1176 iov.iov_base = &seq; 1177 iov.iov_len = sizeof(seq); 1178 xdr_buf_from_iov(&iov, &verf_buf); 1179 mic.data = (u8 *)p; 1180 mic.len = len; 1181 1182 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1183 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1184 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1185 if (maj_stat) { 1186 dprintk("RPC: %5u gss_validate: gss_verify_mic returned " 1187 "error 0x%08x\n", task->tk_pid, maj_stat); 1188 goto out_bad; 1189 } 1190 /* We leave it to unwrap to calculate au_rslack. For now we just 1191 * calculate the length of the verifier: */ 1192 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1193 gss_put_ctx(ctx); 1194 dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n", 1195 task->tk_pid); 1196 return p + XDR_QUADLEN(len); 1197out_bad: 1198 gss_put_ctx(ctx); 1199 dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid); 1200 return NULL; 1201} 1202 1203static inline int 1204gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1205 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1206{ 1207 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1208 struct xdr_buf integ_buf; 1209 __be32 *integ_len = NULL; 1210 struct xdr_netobj mic; 1211 u32 offset; 1212 __be32 *q; 1213 struct kvec *iov; 1214 u32 maj_stat = 0; 1215 int status = -EIO; 1216 1217 integ_len = p++; 1218 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1219 *p++ = htonl(rqstp->rq_seqno); 1220 1221 status = encode(rqstp, p, obj); 1222 if (status) 1223 return status; 1224 1225 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1226 offset, snd_buf->len - offset)) 1227 return status; 1228 *integ_len = htonl(integ_buf.len); 1229 1230 /* guess whether we're in the head or the tail: */ 1231 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1232 iov = snd_buf->tail; 1233 else 1234 iov = snd_buf->head; 1235 p = iov->iov_base + iov->iov_len; 1236 mic.data = (u8 *)(p + 1); 1237 1238 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1239 status = -EIO; /* XXX? */ 1240 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1241 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1242 else if (maj_stat) 1243 return status; 1244 q = xdr_encode_opaque(p, NULL, mic.len); 1245 1246 offset = (u8 *)q - (u8 *)p; 1247 iov->iov_len += offset; 1248 snd_buf->len += offset; 1249 return 0; 1250} 1251 1252static void 1253priv_release_snd_buf(struct rpc_rqst *rqstp) 1254{ 1255 int i; 1256 1257 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1258 __free_page(rqstp->rq_enc_pages[i]); 1259 kfree(rqstp->rq_enc_pages); 1260} 1261 1262static int 1263alloc_enc_pages(struct rpc_rqst *rqstp) 1264{ 1265 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1266 int first, last, i; 1267 1268 if (snd_buf->page_len == 0) { 1269 rqstp->rq_enc_pages_num = 0; 1270 return 0; 1271 } 1272 1273 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1274 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1275 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1276 rqstp->rq_enc_pages 1277 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1278 GFP_NOFS); 1279 if (!rqstp->rq_enc_pages) 1280 goto out; 1281 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1282 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1283 if (rqstp->rq_enc_pages[i] == NULL) 1284 goto out_free; 1285 } 1286 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1287 return 0; 1288out_free: 1289 rqstp->rq_enc_pages_num = i; 1290 priv_release_snd_buf(rqstp); 1291out: 1292 return -EAGAIN; 1293} 1294 1295static inline int 1296gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1297 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1298{ 1299 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1300 u32 offset; 1301 u32 maj_stat; 1302 int status; 1303 __be32 *opaque_len; 1304 struct page **inpages; 1305 int first; 1306 int pad; 1307 struct kvec *iov; 1308 char *tmp; 1309 1310 opaque_len = p++; 1311 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1312 *p++ = htonl(rqstp->rq_seqno); 1313 1314 status = encode(rqstp, p, obj); 1315 if (status) 1316 return status; 1317 1318 status = alloc_enc_pages(rqstp); 1319 if (status) 1320 return status; 1321 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1322 inpages = snd_buf->pages + first; 1323 snd_buf->pages = rqstp->rq_enc_pages; 1324 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1325 /* 1326 * Give the tail its own page, in case we need extra space in the 1327 * head when wrapping: 1328 * 1329 * call_allocate() allocates twice the slack space required 1330 * by the authentication flavor to rq_callsize. 1331 * For GSS, slack is GSS_CRED_SLACK. 1332 */ 1333 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1334 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1335 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1336 snd_buf->tail[0].iov_base = tmp; 1337 } 1338 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1339 /* slack space should prevent this ever happening: */ 1340 BUG_ON(snd_buf->len > snd_buf->buflen); 1341 status = -EIO; 1342 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1343 * done anyway, so it's safe to put the request on the wire: */ 1344 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1345 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1346 else if (maj_stat) 1347 return status; 1348 1349 *opaque_len = htonl(snd_buf->len - offset); 1350 /* guess whether we're in the head or the tail: */ 1351 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1352 iov = snd_buf->tail; 1353 else 1354 iov = snd_buf->head; 1355 p = iov->iov_base + iov->iov_len; 1356 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1357 memset(p, 0, pad); 1358 iov->iov_len += pad; 1359 snd_buf->len += pad; 1360 1361 return 0; 1362} 1363 1364static int 1365gss_wrap_req(struct rpc_task *task, 1366 kxdrproc_t encode, void *rqstp, __be32 *p, void *obj) 1367{ 1368 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1369 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1370 gc_base); 1371 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1372 int status = -EIO; 1373 1374 dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid); 1375 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1376 /* The spec seems a little ambiguous here, but I think that not 1377 * wrapping context destruction requests makes the most sense. 1378 */ 1379 status = encode(rqstp, p, obj); 1380 goto out; 1381 } 1382 switch (gss_cred->gc_service) { 1383 case RPC_GSS_SVC_NONE: 1384 status = encode(rqstp, p, obj); 1385 break; 1386 case RPC_GSS_SVC_INTEGRITY: 1387 status = gss_wrap_req_integ(cred, ctx, encode, 1388 rqstp, p, obj); 1389 break; 1390 case RPC_GSS_SVC_PRIVACY: 1391 status = gss_wrap_req_priv(cred, ctx, encode, 1392 rqstp, p, obj); 1393 break; 1394 } 1395out: 1396 gss_put_ctx(ctx); 1397 dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status); 1398 return status; 1399} 1400 1401static inline int 1402gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1403 struct rpc_rqst *rqstp, __be32 **p) 1404{ 1405 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1406 struct xdr_buf integ_buf; 1407 struct xdr_netobj mic; 1408 u32 data_offset, mic_offset; 1409 u32 integ_len; 1410 u32 maj_stat; 1411 int status = -EIO; 1412 1413 integ_len = ntohl(*(*p)++); 1414 if (integ_len & 3) 1415 return status; 1416 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1417 mic_offset = integ_len + data_offset; 1418 if (mic_offset > rcv_buf->len) 1419 return status; 1420 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1421 return status; 1422 1423 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1424 mic_offset - data_offset)) 1425 return status; 1426 1427 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1428 return status; 1429 1430 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1431 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1432 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1433 if (maj_stat != GSS_S_COMPLETE) 1434 return status; 1435 return 0; 1436} 1437 1438static inline int 1439gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1440 struct rpc_rqst *rqstp, __be32 **p) 1441{ 1442 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1443 u32 offset; 1444 u32 opaque_len; 1445 u32 maj_stat; 1446 int status = -EIO; 1447 1448 opaque_len = ntohl(*(*p)++); 1449 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1450 if (offset + opaque_len > rcv_buf->len) 1451 return status; 1452 /* remove padding: */ 1453 rcv_buf->len = offset + opaque_len; 1454 1455 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1456 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1457 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1458 if (maj_stat != GSS_S_COMPLETE) 1459 return status; 1460 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1461 return status; 1462 1463 return 0; 1464} 1465 1466 1467static int 1468gss_unwrap_resp(struct rpc_task *task, 1469 kxdrproc_t decode, void *rqstp, __be32 *p, void *obj) 1470{ 1471 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1472 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1473 gc_base); 1474 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1475 __be32 *savedp = p; 1476 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1477 int savedlen = head->iov_len; 1478 int status = -EIO; 1479 1480 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1481 goto out_decode; 1482 switch (gss_cred->gc_service) { 1483 case RPC_GSS_SVC_NONE: 1484 break; 1485 case RPC_GSS_SVC_INTEGRITY: 1486 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1487 if (status) 1488 goto out; 1489 break; 1490 case RPC_GSS_SVC_PRIVACY: 1491 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1492 if (status) 1493 goto out; 1494 break; 1495 } 1496 /* take into account extra slack for integrity and privacy cases: */ 1497 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1498 + (savedlen - head->iov_len); 1499out_decode: 1500 status = decode(rqstp, p, obj); 1501out: 1502 gss_put_ctx(ctx); 1503 dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid, 1504 status); 1505 return status; 1506} 1507 1508static const struct rpc_authops authgss_ops = { 1509 .owner = THIS_MODULE, 1510 .au_flavor = RPC_AUTH_GSS, 1511 .au_name = "RPCSEC_GSS", 1512 .create = gss_create, 1513 .destroy = gss_destroy, 1514 .lookup_cred = gss_lookup_cred, 1515 .crcreate = gss_create_cred 1516}; 1517 1518static const struct rpc_credops gss_credops = { 1519 .cr_name = "AUTH_GSS", 1520 .crdestroy = gss_destroy_cred, 1521 .cr_init = gss_cred_init, 1522 .crbind = rpcauth_generic_bind_cred, 1523 .crmatch = gss_match, 1524 .crmarshal = gss_marshal, 1525 .crrefresh = gss_refresh, 1526 .crvalidate = gss_validate, 1527 .crwrap_req = gss_wrap_req, 1528 .crunwrap_resp = gss_unwrap_resp, 1529}; 1530 1531static const struct rpc_credops gss_nullops = { 1532 .cr_name = "AUTH_GSS", 1533 .crdestroy = gss_destroy_nullcred, 1534 .crbind = rpcauth_generic_bind_cred, 1535 .crmatch = gss_match, 1536 .crmarshal = gss_marshal, 1537 .crrefresh = gss_refresh_null, 1538 .crvalidate = gss_validate, 1539 .crwrap_req = gss_wrap_req, 1540 .crunwrap_resp = gss_unwrap_resp, 1541}; 1542 1543static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 1544 .upcall = gss_pipe_upcall, 1545 .downcall = gss_pipe_downcall, 1546 .destroy_msg = gss_pipe_destroy_msg, 1547 .open_pipe = gss_pipe_open_v0, 1548 .release_pipe = gss_pipe_release, 1549}; 1550 1551static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 1552 .upcall = gss_pipe_upcall, 1553 .downcall = gss_pipe_downcall, 1554 .destroy_msg = gss_pipe_destroy_msg, 1555 .open_pipe = gss_pipe_open_v1, 1556 .release_pipe = gss_pipe_release, 1557}; 1558 1559/* 1560 * Initialize RPCSEC_GSS module 1561 */ 1562static int __init init_rpcsec_gss(void) 1563{ 1564 int err = 0; 1565 1566 err = rpcauth_register(&authgss_ops); 1567 if (err) 1568 goto out; 1569 err = gss_svc_init(); 1570 if (err) 1571 goto out_unregister; 1572 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1573 return 0; 1574out_unregister: 1575 rpcauth_unregister(&authgss_ops); 1576out: 1577 return err; 1578} 1579 1580static void __exit exit_rpcsec_gss(void) 1581{ 1582 gss_svc_shutdown(); 1583 rpcauth_unregister(&authgss_ops); 1584 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1585} 1586 1587MODULE_LICENSE("GPL"); 1588module_init(init_rpcsec_gss) 1589module_exit(exit_rpcsec_gss) 1590