auth_gss.c revision 7561042fb7870be0b4ee57efddce68bda8968abf
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); 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 char *p = gss_msg->databuf; 381 int len = 0; 382 383 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ", 384 gss_msg->auth->mech->gm_name, 385 gss_msg->uid); 386 p += gss_msg->msg.len; 387 if (clnt->cl_principal) { 388 len = sprintf(p, "target=%s ", clnt->cl_principal); 389 p += len; 390 gss_msg->msg.len += len; 391 } 392 if (machine_cred) { 393 len = sprintf(p, "service=* "); 394 p += len; 395 gss_msg->msg.len += len; 396 } else if (!strcmp(clnt->cl_program->name, "nfs4_cb")) { 397 len = sprintf(p, "service=nfs "); 398 p += len; 399 gss_msg->msg.len += len; 400 } 401 len = sprintf(p, "\n"); 402 gss_msg->msg.len += len; 403 404 gss_msg->msg.data = gss_msg->databuf; 405 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); 406} 407 408static void gss_encode_msg(struct gss_upcall_msg *gss_msg, 409 struct rpc_clnt *clnt, int machine_cred) 410{ 411 if (pipe_version == 0) 412 gss_encode_v0_msg(gss_msg); 413 else /* pipe_version == 1 */ 414 gss_encode_v1_msg(gss_msg, clnt, machine_cred); 415} 416 417static inline struct gss_upcall_msg * 418gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid, struct rpc_clnt *clnt, 419 int machine_cred) 420{ 421 struct gss_upcall_msg *gss_msg; 422 int vers; 423 424 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 425 if (gss_msg == NULL) 426 return ERR_PTR(-ENOMEM); 427 vers = get_pipe_version(); 428 if (vers < 0) { 429 kfree(gss_msg); 430 return ERR_PTR(vers); 431 } 432 gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode); 433 INIT_LIST_HEAD(&gss_msg->list); 434 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 435 init_waitqueue_head(&gss_msg->waitqueue); 436 atomic_set(&gss_msg->count, 1); 437 gss_msg->uid = uid; 438 gss_msg->auth = gss_auth; 439 gss_encode_msg(gss_msg, clnt, machine_cred); 440 return gss_msg; 441} 442 443static struct gss_upcall_msg * 444gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 445{ 446 struct gss_cred *gss_cred = container_of(cred, 447 struct gss_cred, gc_base); 448 struct gss_upcall_msg *gss_new, *gss_msg; 449 uid_t uid = cred->cr_uid; 450 451 gss_new = gss_alloc_msg(gss_auth, uid, clnt, gss_cred->gc_machine_cred); 452 if (IS_ERR(gss_new)) 453 return gss_new; 454 gss_msg = gss_add_msg(gss_new); 455 if (gss_msg == gss_new) { 456 struct inode *inode = &gss_new->inode->vfs_inode; 457 int res = rpc_queue_upcall(inode, &gss_new->msg); 458 if (res) { 459 gss_unhash_msg(gss_new); 460 gss_msg = ERR_PTR(res); 461 } 462 } else 463 gss_release_msg(gss_new); 464 return gss_msg; 465} 466 467static void warn_gssd(void) 468{ 469 static unsigned long ratelimit; 470 unsigned long now = jiffies; 471 472 if (time_after(now, ratelimit)) { 473 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 474 "Please check user daemon is running.\n"); 475 ratelimit = now + 15*HZ; 476 } 477} 478 479static inline int 480gss_refresh_upcall(struct rpc_task *task) 481{ 482 struct rpc_cred *cred = task->tk_msg.rpc_cred; 483 struct gss_auth *gss_auth = container_of(cred->cr_auth, 484 struct gss_auth, rpc_auth); 485 struct gss_cred *gss_cred = container_of(cred, 486 struct gss_cred, gc_base); 487 struct gss_upcall_msg *gss_msg; 488 struct inode *inode; 489 int err = 0; 490 491 dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid, 492 cred->cr_uid); 493 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 494 if (PTR_ERR(gss_msg) == -EAGAIN) { 495 /* XXX: warning on the first, under the assumption we 496 * shouldn't normally hit this case on a refresh. */ 497 warn_gssd(); 498 task->tk_timeout = 15*HZ; 499 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 500 return 0; 501 } 502 if (IS_ERR(gss_msg)) { 503 err = PTR_ERR(gss_msg); 504 goto out; 505 } 506 inode = &gss_msg->inode->vfs_inode; 507 spin_lock(&inode->i_lock); 508 if (gss_cred->gc_upcall != NULL) 509 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 510 else if (gss_msg->ctx != NULL) { 511 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_msg->ctx); 512 gss_cred->gc_upcall = NULL; 513 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 514 } else if (gss_msg->msg.errno >= 0) { 515 task->tk_timeout = 0; 516 gss_cred->gc_upcall = gss_msg; 517 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 518 atomic_inc(&gss_msg->count); 519 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 520 } else 521 err = gss_msg->msg.errno; 522 spin_unlock(&inode->i_lock); 523 gss_release_msg(gss_msg); 524out: 525 dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n", 526 task->tk_pid, cred->cr_uid, err); 527 return err; 528} 529 530static inline int 531gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 532{ 533 struct inode *inode; 534 struct rpc_cred *cred = &gss_cred->gc_base; 535 struct gss_upcall_msg *gss_msg; 536 DEFINE_WAIT(wait); 537 int err = 0; 538 539 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); 540retry: 541 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 542 if (PTR_ERR(gss_msg) == -EAGAIN) { 543 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 544 pipe_version >= 0, 15*HZ); 545 if (err) 546 goto out; 547 if (pipe_version < 0) 548 warn_gssd(); 549 goto retry; 550 } 551 if (IS_ERR(gss_msg)) { 552 err = PTR_ERR(gss_msg); 553 goto out; 554 } 555 inode = &gss_msg->inode->vfs_inode; 556 for (;;) { 557 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); 558 spin_lock(&inode->i_lock); 559 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 560 break; 561 } 562 spin_unlock(&inode->i_lock); 563 if (signalled()) { 564 err = -ERESTARTSYS; 565 goto out_intr; 566 } 567 schedule(); 568 } 569 if (gss_msg->ctx) 570 gss_cred_set_ctx(cred, gss_msg->ctx); 571 else 572 err = gss_msg->msg.errno; 573 spin_unlock(&inode->i_lock); 574out_intr: 575 finish_wait(&gss_msg->waitqueue, &wait); 576 gss_release_msg(gss_msg); 577out: 578 dprintk("RPC: gss_create_upcall for uid %u result %d\n", 579 cred->cr_uid, err); 580 return err; 581} 582 583static ssize_t 584gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, 585 char __user *dst, size_t buflen) 586{ 587 char *data = (char *)msg->data + msg->copied; 588 size_t mlen = min(msg->len, buflen); 589 unsigned long left; 590 591 left = copy_to_user(dst, data, mlen); 592 if (left == mlen) { 593 msg->errno = -EFAULT; 594 return -EFAULT; 595 } 596 597 mlen -= left; 598 msg->copied += mlen; 599 msg->errno = 0; 600 return mlen; 601} 602 603#define MSG_BUF_MAXSIZE 1024 604 605static ssize_t 606gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 607{ 608 const void *p, *end; 609 void *buf; 610 struct gss_upcall_msg *gss_msg; 611 struct inode *inode = filp->f_path.dentry->d_inode; 612 struct gss_cl_ctx *ctx; 613 uid_t uid; 614 ssize_t err = -EFBIG; 615 616 if (mlen > MSG_BUF_MAXSIZE) 617 goto out; 618 err = -ENOMEM; 619 buf = kmalloc(mlen, GFP_NOFS); 620 if (!buf) 621 goto out; 622 623 err = -EFAULT; 624 if (copy_from_user(buf, src, mlen)) 625 goto err; 626 627 end = (const void *)((char *)buf + mlen); 628 p = simple_get_bytes(buf, end, &uid, sizeof(uid)); 629 if (IS_ERR(p)) { 630 err = PTR_ERR(p); 631 goto err; 632 } 633 634 err = -ENOMEM; 635 ctx = gss_alloc_context(); 636 if (ctx == NULL) 637 goto err; 638 639 err = -ENOENT; 640 /* Find a matching upcall */ 641 spin_lock(&inode->i_lock); 642 gss_msg = __gss_find_upcall(RPC_I(inode), uid); 643 if (gss_msg == NULL) { 644 spin_unlock(&inode->i_lock); 645 goto err_put_ctx; 646 } 647 list_del_init(&gss_msg->list); 648 spin_unlock(&inode->i_lock); 649 650 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); 651 if (IS_ERR(p)) { 652 err = PTR_ERR(p); 653 switch (err) { 654 case -EACCES: 655 case -EKEYEXPIRED: 656 gss_msg->msg.errno = err; 657 err = mlen; 658 break; 659 case -EFAULT: 660 case -ENOMEM: 661 case -EINVAL: 662 case -ENOSYS: 663 gss_msg->msg.errno = -EAGAIN; 664 break; 665 default: 666 printk(KERN_CRIT "%s: bad return from " 667 "gss_fill_context: %zd\n", __func__, err); 668 BUG(); 669 } 670 goto err_release_msg; 671 } 672 gss_msg->ctx = gss_get_ctx(ctx); 673 err = mlen; 674 675err_release_msg: 676 spin_lock(&inode->i_lock); 677 __gss_unhash_msg(gss_msg); 678 spin_unlock(&inode->i_lock); 679 gss_release_msg(gss_msg); 680err_put_ctx: 681 gss_put_ctx(ctx); 682err: 683 kfree(buf); 684out: 685 dprintk("RPC: gss_pipe_downcall returning %Zd\n", err); 686 return err; 687} 688 689static int gss_pipe_open(struct inode *inode, int new_version) 690{ 691 int ret = 0; 692 693 spin_lock(&pipe_version_lock); 694 if (pipe_version < 0) { 695 /* First open of any gss pipe determines the version: */ 696 pipe_version = new_version; 697 rpc_wake_up(&pipe_version_rpc_waitqueue); 698 wake_up(&pipe_version_waitqueue); 699 } else if (pipe_version != new_version) { 700 /* Trying to open a pipe of a different version */ 701 ret = -EBUSY; 702 goto out; 703 } 704 atomic_inc(&pipe_users); 705out: 706 spin_unlock(&pipe_version_lock); 707 return ret; 708 709} 710 711static int gss_pipe_open_v0(struct inode *inode) 712{ 713 return gss_pipe_open(inode, 0); 714} 715 716static int gss_pipe_open_v1(struct inode *inode) 717{ 718 return gss_pipe_open(inode, 1); 719} 720 721static void 722gss_pipe_release(struct inode *inode) 723{ 724 struct rpc_inode *rpci = RPC_I(inode); 725 struct gss_upcall_msg *gss_msg; 726 727 spin_lock(&inode->i_lock); 728 while (!list_empty(&rpci->in_downcall)) { 729 730 gss_msg = list_entry(rpci->in_downcall.next, 731 struct gss_upcall_msg, list); 732 gss_msg->msg.errno = -EPIPE; 733 atomic_inc(&gss_msg->count); 734 __gss_unhash_msg(gss_msg); 735 spin_unlock(&inode->i_lock); 736 gss_release_msg(gss_msg); 737 spin_lock(&inode->i_lock); 738 } 739 spin_unlock(&inode->i_lock); 740 741 put_pipe_version(); 742} 743 744static void 745gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 746{ 747 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 748 749 if (msg->errno < 0) { 750 dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n", 751 gss_msg); 752 atomic_inc(&gss_msg->count); 753 gss_unhash_msg(gss_msg); 754 if (msg->errno == -ETIMEDOUT) 755 warn_gssd(); 756 gss_release_msg(gss_msg); 757 } 758} 759 760/* 761 * NOTE: we have the opportunity to use different 762 * parameters based on the input flavor (which must be a pseudoflavor) 763 */ 764static struct rpc_auth * 765gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 766{ 767 struct gss_auth *gss_auth; 768 struct rpc_auth * auth; 769 int err = -ENOMEM; /* XXX? */ 770 771 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 772 773 if (!try_module_get(THIS_MODULE)) 774 return ERR_PTR(err); 775 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 776 goto out_dec; 777 gss_auth->client = clnt; 778 err = -EINVAL; 779 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 780 if (!gss_auth->mech) { 781 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 782 __func__, flavor); 783 goto err_free; 784 } 785 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 786 if (gss_auth->service == 0) 787 goto err_put_mech; 788 auth = &gss_auth->rpc_auth; 789 auth->au_cslack = GSS_CRED_SLACK >> 2; 790 auth->au_rslack = GSS_VERF_SLACK >> 2; 791 auth->au_ops = &authgss_ops; 792 auth->au_flavor = flavor; 793 atomic_set(&auth->au_count, 1); 794 kref_init(&gss_auth->kref); 795 796 /* 797 * Note: if we created the old pipe first, then someone who 798 * examined the directory at the right moment might conclude 799 * that we supported only the old pipe. So we instead create 800 * the new pipe first. 801 */ 802 gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_path.dentry, 803 "gssd", 804 clnt, &gss_upcall_ops_v1, 805 RPC_PIPE_WAIT_FOR_OPEN); 806 if (IS_ERR(gss_auth->dentry[1])) { 807 err = PTR_ERR(gss_auth->dentry[1]); 808 goto err_put_mech; 809 } 810 811 gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_path.dentry, 812 gss_auth->mech->gm_name, 813 clnt, &gss_upcall_ops_v0, 814 RPC_PIPE_WAIT_FOR_OPEN); 815 if (IS_ERR(gss_auth->dentry[0])) { 816 err = PTR_ERR(gss_auth->dentry[0]); 817 goto err_unlink_pipe_1; 818 } 819 err = rpcauth_init_credcache(auth); 820 if (err) 821 goto err_unlink_pipe_0; 822 823 return auth; 824err_unlink_pipe_0: 825 rpc_unlink(gss_auth->dentry[0]); 826err_unlink_pipe_1: 827 rpc_unlink(gss_auth->dentry[1]); 828err_put_mech: 829 gss_mech_put(gss_auth->mech); 830err_free: 831 kfree(gss_auth); 832out_dec: 833 module_put(THIS_MODULE); 834 return ERR_PTR(err); 835} 836 837static void 838gss_free(struct gss_auth *gss_auth) 839{ 840 rpc_unlink(gss_auth->dentry[1]); 841 rpc_unlink(gss_auth->dentry[0]); 842 gss_mech_put(gss_auth->mech); 843 844 kfree(gss_auth); 845 module_put(THIS_MODULE); 846} 847 848static void 849gss_free_callback(struct kref *kref) 850{ 851 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 852 853 gss_free(gss_auth); 854} 855 856static void 857gss_destroy(struct rpc_auth *auth) 858{ 859 struct gss_auth *gss_auth; 860 861 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 862 auth, auth->au_flavor); 863 864 rpcauth_destroy_credcache(auth); 865 866 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 867 kref_put(&gss_auth->kref, gss_free_callback); 868} 869 870/* 871 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 872 * to the server with the GSS control procedure field set to 873 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 874 * all RPCSEC_GSS state associated with that context. 875 */ 876static int 877gss_destroying_context(struct rpc_cred *cred) 878{ 879 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 880 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 881 struct rpc_task *task; 882 883 if (gss_cred->gc_ctx == NULL || 884 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 885 return 0; 886 887 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 888 cred->cr_ops = &gss_nullops; 889 890 /* Take a reference to ensure the cred will be destroyed either 891 * by the RPC call or by the put_rpccred() below */ 892 get_rpccred(cred); 893 894 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 895 if (!IS_ERR(task)) 896 rpc_put_task(task); 897 898 put_rpccred(cred); 899 return 1; 900} 901 902/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 903 * to create a new cred or context, so they check that things have been 904 * allocated before freeing them. */ 905static void 906gss_do_free_ctx(struct gss_cl_ctx *ctx) 907{ 908 dprintk("RPC: gss_free_ctx\n"); 909 910 kfree(ctx->gc_wire_ctx.data); 911 kfree(ctx); 912} 913 914static void 915gss_free_ctx_callback(struct rcu_head *head) 916{ 917 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 918 gss_do_free_ctx(ctx); 919} 920 921static void 922gss_free_ctx(struct gss_cl_ctx *ctx) 923{ 924 struct gss_ctx *gc_gss_ctx; 925 926 gc_gss_ctx = rcu_dereference(ctx->gc_gss_ctx); 927 rcu_assign_pointer(ctx->gc_gss_ctx, NULL); 928 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 929 if (gc_gss_ctx) 930 gss_delete_sec_context(&gc_gss_ctx); 931} 932 933static void 934gss_free_cred(struct gss_cred *gss_cred) 935{ 936 dprintk("RPC: gss_free_cred %p\n", gss_cred); 937 kfree(gss_cred); 938} 939 940static void 941gss_free_cred_callback(struct rcu_head *head) 942{ 943 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 944 gss_free_cred(gss_cred); 945} 946 947static void 948gss_destroy_nullcred(struct rpc_cred *cred) 949{ 950 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 951 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 952 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 953 954 rcu_assign_pointer(gss_cred->gc_ctx, NULL); 955 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 956 if (ctx) 957 gss_put_ctx(ctx); 958 kref_put(&gss_auth->kref, gss_free_callback); 959} 960 961static void 962gss_destroy_cred(struct rpc_cred *cred) 963{ 964 965 if (gss_destroying_context(cred)) 966 return; 967 gss_destroy_nullcred(cred); 968} 969 970/* 971 * Lookup RPCSEC_GSS cred for the current process 972 */ 973static struct rpc_cred * 974gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 975{ 976 return rpcauth_lookup_credcache(auth, acred, flags); 977} 978 979static struct rpc_cred * 980gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 981{ 982 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 983 struct gss_cred *cred = NULL; 984 int err = -ENOMEM; 985 986 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 987 acred->uid, auth->au_flavor); 988 989 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 990 goto out_err; 991 992 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 993 /* 994 * Note: in order to force a call to call_refresh(), we deliberately 995 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 996 */ 997 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 998 cred->gc_service = gss_auth->service; 999 cred->gc_machine_cred = acred->machine_cred; 1000 kref_get(&gss_auth->kref); 1001 return &cred->gc_base; 1002 1003out_err: 1004 dprintk("RPC: gss_create_cred failed with error %d\n", err); 1005 return ERR_PTR(err); 1006} 1007 1008static int 1009gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1010{ 1011 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1012 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1013 int err; 1014 1015 do { 1016 err = gss_create_upcall(gss_auth, gss_cred); 1017 } while (err == -EAGAIN); 1018 return err; 1019} 1020 1021static int 1022gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1023{ 1024 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1025 1026 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1027 goto out; 1028 /* Don't match with creds that have expired. */ 1029 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1030 return 0; 1031 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1032 return 0; 1033out: 1034 if (acred->machine_cred != gss_cred->gc_machine_cred) 1035 return 0; 1036 return (rc->cr_uid == acred->uid); 1037} 1038 1039/* 1040* Marshal credentials. 1041* Maybe we should keep a cached credential for performance reasons. 1042*/ 1043static __be32 * 1044gss_marshal(struct rpc_task *task, __be32 *p) 1045{ 1046 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1047 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1048 gc_base); 1049 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1050 __be32 *cred_len; 1051 struct rpc_rqst *req = task->tk_rqstp; 1052 u32 maj_stat = 0; 1053 struct xdr_netobj mic; 1054 struct kvec iov; 1055 struct xdr_buf verf_buf; 1056 1057 dprintk("RPC: %5u gss_marshal\n", task->tk_pid); 1058 1059 *p++ = htonl(RPC_AUTH_GSS); 1060 cred_len = p++; 1061 1062 spin_lock(&ctx->gc_seq_lock); 1063 req->rq_seqno = ctx->gc_seq++; 1064 spin_unlock(&ctx->gc_seq_lock); 1065 1066 *p++ = htonl((u32) RPC_GSS_VERSION); 1067 *p++ = htonl((u32) ctx->gc_proc); 1068 *p++ = htonl((u32) req->rq_seqno); 1069 *p++ = htonl((u32) gss_cred->gc_service); 1070 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1071 *cred_len = htonl((p - (cred_len + 1)) << 2); 1072 1073 /* We compute the checksum for the verifier over the xdr-encoded bytes 1074 * starting with the xid and ending at the end of the credential: */ 1075 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 1076 req->rq_snd_buf.head[0].iov_base); 1077 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1078 xdr_buf_from_iov(&iov, &verf_buf); 1079 1080 /* set verifier flavor*/ 1081 *p++ = htonl(RPC_AUTH_GSS); 1082 1083 mic.data = (u8 *)(p + 1); 1084 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1085 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1086 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1087 } else if (maj_stat != 0) { 1088 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1089 goto out_put_ctx; 1090 } 1091 p = xdr_encode_opaque(p, NULL, mic.len); 1092 gss_put_ctx(ctx); 1093 return p; 1094out_put_ctx: 1095 gss_put_ctx(ctx); 1096 return NULL; 1097} 1098 1099static int gss_renew_cred(struct rpc_task *task) 1100{ 1101 struct rpc_cred *oldcred = task->tk_msg.rpc_cred; 1102 struct gss_cred *gss_cred = container_of(oldcred, 1103 struct gss_cred, 1104 gc_base); 1105 struct rpc_auth *auth = oldcred->cr_auth; 1106 struct auth_cred acred = { 1107 .uid = oldcred->cr_uid, 1108 .machine_cred = gss_cred->gc_machine_cred, 1109 }; 1110 struct rpc_cred *new; 1111 1112 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1113 if (IS_ERR(new)) 1114 return PTR_ERR(new); 1115 task->tk_msg.rpc_cred = new; 1116 put_rpccred(oldcred); 1117 return 0; 1118} 1119 1120/* 1121* Refresh credentials. XXX - finish 1122*/ 1123static int 1124gss_refresh(struct rpc_task *task) 1125{ 1126 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1127 int ret = 0; 1128 1129 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1130 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1131 ret = gss_renew_cred(task); 1132 if (ret < 0) 1133 goto out; 1134 cred = task->tk_msg.rpc_cred; 1135 } 1136 1137 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1138 ret = gss_refresh_upcall(task); 1139out: 1140 return ret; 1141} 1142 1143/* Dummy refresh routine: used only when destroying the context */ 1144static int 1145gss_refresh_null(struct rpc_task *task) 1146{ 1147 return -EACCES; 1148} 1149 1150static __be32 * 1151gss_validate(struct rpc_task *task, __be32 *p) 1152{ 1153 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1154 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1155 __be32 seq; 1156 struct kvec iov; 1157 struct xdr_buf verf_buf; 1158 struct xdr_netobj mic; 1159 u32 flav,len; 1160 u32 maj_stat; 1161 1162 dprintk("RPC: %5u gss_validate\n", task->tk_pid); 1163 1164 flav = ntohl(*p++); 1165 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1166 goto out_bad; 1167 if (flav != RPC_AUTH_GSS) 1168 goto out_bad; 1169 seq = htonl(task->tk_rqstp->rq_seqno); 1170 iov.iov_base = &seq; 1171 iov.iov_len = sizeof(seq); 1172 xdr_buf_from_iov(&iov, &verf_buf); 1173 mic.data = (u8 *)p; 1174 mic.len = len; 1175 1176 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1177 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1178 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1179 if (maj_stat) { 1180 dprintk("RPC: %5u gss_validate: gss_verify_mic returned " 1181 "error 0x%08x\n", task->tk_pid, maj_stat); 1182 goto out_bad; 1183 } 1184 /* We leave it to unwrap to calculate au_rslack. For now we just 1185 * calculate the length of the verifier: */ 1186 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1187 gss_put_ctx(ctx); 1188 dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n", 1189 task->tk_pid); 1190 return p + XDR_QUADLEN(len); 1191out_bad: 1192 gss_put_ctx(ctx); 1193 dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid); 1194 return NULL; 1195} 1196 1197static inline int 1198gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1199 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1200{ 1201 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1202 struct xdr_buf integ_buf; 1203 __be32 *integ_len = NULL; 1204 struct xdr_netobj mic; 1205 u32 offset; 1206 __be32 *q; 1207 struct kvec *iov; 1208 u32 maj_stat = 0; 1209 int status = -EIO; 1210 1211 integ_len = p++; 1212 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1213 *p++ = htonl(rqstp->rq_seqno); 1214 1215 status = encode(rqstp, p, obj); 1216 if (status) 1217 return status; 1218 1219 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1220 offset, snd_buf->len - offset)) 1221 return status; 1222 *integ_len = htonl(integ_buf.len); 1223 1224 /* guess whether we're in the head or the tail: */ 1225 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1226 iov = snd_buf->tail; 1227 else 1228 iov = snd_buf->head; 1229 p = iov->iov_base + iov->iov_len; 1230 mic.data = (u8 *)(p + 1); 1231 1232 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1233 status = -EIO; /* XXX? */ 1234 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1235 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1236 else if (maj_stat) 1237 return status; 1238 q = xdr_encode_opaque(p, NULL, mic.len); 1239 1240 offset = (u8 *)q - (u8 *)p; 1241 iov->iov_len += offset; 1242 snd_buf->len += offset; 1243 return 0; 1244} 1245 1246static void 1247priv_release_snd_buf(struct rpc_rqst *rqstp) 1248{ 1249 int i; 1250 1251 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1252 __free_page(rqstp->rq_enc_pages[i]); 1253 kfree(rqstp->rq_enc_pages); 1254} 1255 1256static int 1257alloc_enc_pages(struct rpc_rqst *rqstp) 1258{ 1259 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1260 int first, last, i; 1261 1262 if (snd_buf->page_len == 0) { 1263 rqstp->rq_enc_pages_num = 0; 1264 return 0; 1265 } 1266 1267 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1268 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1269 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1270 rqstp->rq_enc_pages 1271 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1272 GFP_NOFS); 1273 if (!rqstp->rq_enc_pages) 1274 goto out; 1275 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1276 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1277 if (rqstp->rq_enc_pages[i] == NULL) 1278 goto out_free; 1279 } 1280 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1281 return 0; 1282out_free: 1283 rqstp->rq_enc_pages_num = i; 1284 priv_release_snd_buf(rqstp); 1285out: 1286 return -EAGAIN; 1287} 1288 1289static inline int 1290gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1291 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1292{ 1293 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1294 u32 offset; 1295 u32 maj_stat; 1296 int status; 1297 __be32 *opaque_len; 1298 struct page **inpages; 1299 int first; 1300 int pad; 1301 struct kvec *iov; 1302 char *tmp; 1303 1304 opaque_len = p++; 1305 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1306 *p++ = htonl(rqstp->rq_seqno); 1307 1308 status = encode(rqstp, p, obj); 1309 if (status) 1310 return status; 1311 1312 status = alloc_enc_pages(rqstp); 1313 if (status) 1314 return status; 1315 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1316 inpages = snd_buf->pages + first; 1317 snd_buf->pages = rqstp->rq_enc_pages; 1318 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1319 /* 1320 * Give the tail its own page, in case we need extra space in the 1321 * head when wrapping: 1322 * 1323 * call_allocate() allocates twice the slack space required 1324 * by the authentication flavor to rq_callsize. 1325 * For GSS, slack is GSS_CRED_SLACK. 1326 */ 1327 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1328 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1329 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1330 snd_buf->tail[0].iov_base = tmp; 1331 } 1332 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1333 /* slack space should prevent this ever happening: */ 1334 BUG_ON(snd_buf->len > snd_buf->buflen); 1335 status = -EIO; 1336 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1337 * done anyway, so it's safe to put the request on the wire: */ 1338 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1339 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1340 else if (maj_stat) 1341 return status; 1342 1343 *opaque_len = htonl(snd_buf->len - offset); 1344 /* guess whether we're in the head or the tail: */ 1345 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1346 iov = snd_buf->tail; 1347 else 1348 iov = snd_buf->head; 1349 p = iov->iov_base + iov->iov_len; 1350 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1351 memset(p, 0, pad); 1352 iov->iov_len += pad; 1353 snd_buf->len += pad; 1354 1355 return 0; 1356} 1357 1358static int 1359gss_wrap_req(struct rpc_task *task, 1360 kxdrproc_t encode, void *rqstp, __be32 *p, void *obj) 1361{ 1362 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1363 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1364 gc_base); 1365 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1366 int status = -EIO; 1367 1368 dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid); 1369 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1370 /* The spec seems a little ambiguous here, but I think that not 1371 * wrapping context destruction requests makes the most sense. 1372 */ 1373 status = encode(rqstp, p, obj); 1374 goto out; 1375 } 1376 switch (gss_cred->gc_service) { 1377 case RPC_GSS_SVC_NONE: 1378 status = encode(rqstp, p, obj); 1379 break; 1380 case RPC_GSS_SVC_INTEGRITY: 1381 status = gss_wrap_req_integ(cred, ctx, encode, 1382 rqstp, p, obj); 1383 break; 1384 case RPC_GSS_SVC_PRIVACY: 1385 status = gss_wrap_req_priv(cred, ctx, encode, 1386 rqstp, p, obj); 1387 break; 1388 } 1389out: 1390 gss_put_ctx(ctx); 1391 dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status); 1392 return status; 1393} 1394 1395static inline int 1396gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1397 struct rpc_rqst *rqstp, __be32 **p) 1398{ 1399 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1400 struct xdr_buf integ_buf; 1401 struct xdr_netobj mic; 1402 u32 data_offset, mic_offset; 1403 u32 integ_len; 1404 u32 maj_stat; 1405 int status = -EIO; 1406 1407 integ_len = ntohl(*(*p)++); 1408 if (integ_len & 3) 1409 return status; 1410 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1411 mic_offset = integ_len + data_offset; 1412 if (mic_offset > rcv_buf->len) 1413 return status; 1414 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1415 return status; 1416 1417 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1418 mic_offset - data_offset)) 1419 return status; 1420 1421 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1422 return status; 1423 1424 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1425 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1426 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1427 if (maj_stat != GSS_S_COMPLETE) 1428 return status; 1429 return 0; 1430} 1431 1432static inline int 1433gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1434 struct rpc_rqst *rqstp, __be32 **p) 1435{ 1436 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1437 u32 offset; 1438 u32 opaque_len; 1439 u32 maj_stat; 1440 int status = -EIO; 1441 1442 opaque_len = ntohl(*(*p)++); 1443 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1444 if (offset + opaque_len > rcv_buf->len) 1445 return status; 1446 /* remove padding: */ 1447 rcv_buf->len = offset + opaque_len; 1448 1449 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1450 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1451 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1452 if (maj_stat != GSS_S_COMPLETE) 1453 return status; 1454 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1455 return status; 1456 1457 return 0; 1458} 1459 1460 1461static int 1462gss_unwrap_resp(struct rpc_task *task, 1463 kxdrproc_t decode, void *rqstp, __be32 *p, void *obj) 1464{ 1465 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1466 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1467 gc_base); 1468 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1469 __be32 *savedp = p; 1470 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1471 int savedlen = head->iov_len; 1472 int status = -EIO; 1473 1474 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1475 goto out_decode; 1476 switch (gss_cred->gc_service) { 1477 case RPC_GSS_SVC_NONE: 1478 break; 1479 case RPC_GSS_SVC_INTEGRITY: 1480 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1481 if (status) 1482 goto out; 1483 break; 1484 case RPC_GSS_SVC_PRIVACY: 1485 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1486 if (status) 1487 goto out; 1488 break; 1489 } 1490 /* take into account extra slack for integrity and privacy cases: */ 1491 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1492 + (savedlen - head->iov_len); 1493out_decode: 1494 status = decode(rqstp, p, obj); 1495out: 1496 gss_put_ctx(ctx); 1497 dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid, 1498 status); 1499 return status; 1500} 1501 1502static const struct rpc_authops authgss_ops = { 1503 .owner = THIS_MODULE, 1504 .au_flavor = RPC_AUTH_GSS, 1505 .au_name = "RPCSEC_GSS", 1506 .create = gss_create, 1507 .destroy = gss_destroy, 1508 .lookup_cred = gss_lookup_cred, 1509 .crcreate = gss_create_cred 1510}; 1511 1512static const struct rpc_credops gss_credops = { 1513 .cr_name = "AUTH_GSS", 1514 .crdestroy = gss_destroy_cred, 1515 .cr_init = gss_cred_init, 1516 .crbind = rpcauth_generic_bind_cred, 1517 .crmatch = gss_match, 1518 .crmarshal = gss_marshal, 1519 .crrefresh = gss_refresh, 1520 .crvalidate = gss_validate, 1521 .crwrap_req = gss_wrap_req, 1522 .crunwrap_resp = gss_unwrap_resp, 1523}; 1524 1525static const struct rpc_credops gss_nullops = { 1526 .cr_name = "AUTH_GSS", 1527 .crdestroy = gss_destroy_nullcred, 1528 .crbind = rpcauth_generic_bind_cred, 1529 .crmatch = gss_match, 1530 .crmarshal = gss_marshal, 1531 .crrefresh = gss_refresh_null, 1532 .crvalidate = gss_validate, 1533 .crwrap_req = gss_wrap_req, 1534 .crunwrap_resp = gss_unwrap_resp, 1535}; 1536 1537static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 1538 .upcall = gss_pipe_upcall, 1539 .downcall = gss_pipe_downcall, 1540 .destroy_msg = gss_pipe_destroy_msg, 1541 .open_pipe = gss_pipe_open_v0, 1542 .release_pipe = gss_pipe_release, 1543}; 1544 1545static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 1546 .upcall = gss_pipe_upcall, 1547 .downcall = gss_pipe_downcall, 1548 .destroy_msg = gss_pipe_destroy_msg, 1549 .open_pipe = gss_pipe_open_v1, 1550 .release_pipe = gss_pipe_release, 1551}; 1552 1553/* 1554 * Initialize RPCSEC_GSS module 1555 */ 1556static int __init init_rpcsec_gss(void) 1557{ 1558 int err = 0; 1559 1560 err = rpcauth_register(&authgss_ops); 1561 if (err) 1562 goto out; 1563 err = gss_svc_init(); 1564 if (err) 1565 goto out_unregister; 1566 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1567 return 0; 1568out_unregister: 1569 rpcauth_unregister(&authgss_ops); 1570out: 1571 return err; 1572} 1573 1574static void __exit exit_rpcsec_gss(void) 1575{ 1576 gss_svc_shutdown(); 1577 rpcauth_unregister(&authgss_ops); 1578 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1579} 1580 1581MODULE_LICENSE("GPL"); 1582module_init(init_rpcsec_gss) 1583module_exit(exit_rpcsec_gss) 1584