auth_gss.c revision 2446ab6070861aba2dd9229463ffbc40016a9f33
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#define GSS_RETRY_EXPIRED 5 61static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED; 62 63#ifdef RPC_DEBUG 64# define RPCDBG_FACILITY RPCDBG_AUTH 65#endif 66 67#define GSS_CRED_SLACK (RPC_MAX_AUTH_SIZE * 2) 68/* length of a krb5 verifier (48), plus data added before arguments when 69 * using integrity (two 4-byte integers): */ 70#define GSS_VERF_SLACK 100 71 72struct gss_auth { 73 struct kref kref; 74 struct rpc_auth rpc_auth; 75 struct gss_api_mech *mech; 76 enum rpc_gss_svc service; 77 struct rpc_clnt *client; 78 /* 79 * There are two upcall pipes; dentry[1], named "gssd", is used 80 * for the new text-based upcall; dentry[0] is named after the 81 * mechanism (for example, "krb5") and exists for 82 * backwards-compatibility with older gssd's. 83 */ 84 struct rpc_pipe *pipe[2]; 85}; 86 87/* pipe_version >= 0 if and only if someone has a pipe open. */ 88static int pipe_version = -1; 89static atomic_t pipe_users = ATOMIC_INIT(0); 90static DEFINE_SPINLOCK(pipe_version_lock); 91static struct rpc_wait_queue pipe_version_rpc_waitqueue; 92static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue); 93 94static void gss_free_ctx(struct gss_cl_ctx *); 95static const struct rpc_pipe_ops gss_upcall_ops_v0; 96static const struct rpc_pipe_ops gss_upcall_ops_v1; 97 98static inline struct gss_cl_ctx * 99gss_get_ctx(struct gss_cl_ctx *ctx) 100{ 101 atomic_inc(&ctx->count); 102 return ctx; 103} 104 105static inline void 106gss_put_ctx(struct gss_cl_ctx *ctx) 107{ 108 if (atomic_dec_and_test(&ctx->count)) 109 gss_free_ctx(ctx); 110} 111 112/* gss_cred_set_ctx: 113 * called by gss_upcall_callback and gss_create_upcall in order 114 * to set the gss context. The actual exchange of an old context 115 * and a new one is protected by the pipe->lock. 116 */ 117static void 118gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) 119{ 120 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 121 122 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 123 return; 124 gss_get_ctx(ctx); 125 rcu_assign_pointer(gss_cred->gc_ctx, ctx); 126 set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 127 smp_mb__before_clear_bit(); 128 clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags); 129} 130 131static const void * 132simple_get_bytes(const void *p, const void *end, void *res, size_t len) 133{ 134 const void *q = (const void *)((const char *)p + len); 135 if (unlikely(q > end || q < p)) 136 return ERR_PTR(-EFAULT); 137 memcpy(res, p, len); 138 return q; 139} 140 141static inline const void * 142simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) 143{ 144 const void *q; 145 unsigned int len; 146 147 p = simple_get_bytes(p, end, &len, sizeof(len)); 148 if (IS_ERR(p)) 149 return p; 150 q = (const void *)((const char *)p + len); 151 if (unlikely(q > end || q < p)) 152 return ERR_PTR(-EFAULT); 153 dest->data = kmemdup(p, len, GFP_NOFS); 154 if (unlikely(dest->data == NULL)) 155 return ERR_PTR(-ENOMEM); 156 dest->len = len; 157 return q; 158} 159 160static struct gss_cl_ctx * 161gss_cred_get_ctx(struct rpc_cred *cred) 162{ 163 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 164 struct gss_cl_ctx *ctx = NULL; 165 166 rcu_read_lock(); 167 if (gss_cred->gc_ctx) 168 ctx = gss_get_ctx(gss_cred->gc_ctx); 169 rcu_read_unlock(); 170 return ctx; 171} 172 173static struct gss_cl_ctx * 174gss_alloc_context(void) 175{ 176 struct gss_cl_ctx *ctx; 177 178 ctx = kzalloc(sizeof(*ctx), GFP_NOFS); 179 if (ctx != NULL) { 180 ctx->gc_proc = RPC_GSS_PROC_DATA; 181 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ 182 spin_lock_init(&ctx->gc_seq_lock); 183 atomic_set(&ctx->count,1); 184 } 185 return ctx; 186} 187 188#define GSSD_MIN_TIMEOUT (60 * 60) 189static const void * 190gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) 191{ 192 const void *q; 193 unsigned int seclen; 194 unsigned int timeout; 195 u32 window_size; 196 int ret; 197 198 /* First unsigned int gives the lifetime (in seconds) of the cred */ 199 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 200 if (IS_ERR(p)) 201 goto err; 202 if (timeout == 0) 203 timeout = GSSD_MIN_TIMEOUT; 204 ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4; 205 /* Sequence number window. Determines the maximum number of simultaneous requests */ 206 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 207 if (IS_ERR(p)) 208 goto err; 209 ctx->gc_win = window_size; 210 /* gssd signals an error by passing ctx->gc_win = 0: */ 211 if (ctx->gc_win == 0) { 212 /* 213 * in which case, p points to an error code. Anything other 214 * than -EKEYEXPIRED gets converted to -EACCES. 215 */ 216 p = simple_get_bytes(p, end, &ret, sizeof(ret)); 217 if (!IS_ERR(p)) 218 p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) : 219 ERR_PTR(-EACCES); 220 goto err; 221 } 222 /* copy the opaque wire context */ 223 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 224 if (IS_ERR(p)) 225 goto err; 226 /* import the opaque security context */ 227 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 228 if (IS_ERR(p)) 229 goto err; 230 q = (const void *)((const char *)p + seclen); 231 if (unlikely(q > end || q < p)) { 232 p = ERR_PTR(-EFAULT); 233 goto err; 234 } 235 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, GFP_NOFS); 236 if (ret < 0) { 237 p = ERR_PTR(ret); 238 goto err; 239 } 240 return q; 241err: 242 dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p)); 243 return p; 244} 245 246#define UPCALL_BUF_LEN 128 247 248struct gss_upcall_msg { 249 atomic_t count; 250 uid_t uid; 251 struct rpc_pipe_msg msg; 252 struct list_head list; 253 struct gss_auth *auth; 254 struct rpc_pipe *pipe; 255 struct rpc_wait_queue rpc_waitqueue; 256 wait_queue_head_t waitqueue; 257 struct gss_cl_ctx *ctx; 258 char databuf[UPCALL_BUF_LEN]; 259}; 260 261static int get_pipe_version(void) 262{ 263 int ret; 264 265 spin_lock(&pipe_version_lock); 266 if (pipe_version >= 0) { 267 atomic_inc(&pipe_users); 268 ret = pipe_version; 269 } else 270 ret = -EAGAIN; 271 spin_unlock(&pipe_version_lock); 272 return ret; 273} 274 275static void put_pipe_version(void) 276{ 277 if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) { 278 pipe_version = -1; 279 spin_unlock(&pipe_version_lock); 280 } 281} 282 283static void 284gss_release_msg(struct gss_upcall_msg *gss_msg) 285{ 286 if (!atomic_dec_and_test(&gss_msg->count)) 287 return; 288 put_pipe_version(); 289 BUG_ON(!list_empty(&gss_msg->list)); 290 if (gss_msg->ctx != NULL) 291 gss_put_ctx(gss_msg->ctx); 292 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue); 293 kfree(gss_msg); 294} 295 296static struct gss_upcall_msg * 297__gss_find_upcall(struct rpc_pipe *pipe, uid_t uid) 298{ 299 struct gss_upcall_msg *pos; 300 list_for_each_entry(pos, &pipe->in_downcall, list) { 301 if (pos->uid != uid) 302 continue; 303 atomic_inc(&pos->count); 304 dprintk("RPC: gss_find_upcall found msg %p\n", pos); 305 return pos; 306 } 307 dprintk("RPC: gss_find_upcall found nothing\n"); 308 return NULL; 309} 310 311/* Try to add an upcall to the pipefs queue. 312 * If an upcall owned by our uid already exists, then we return a reference 313 * to that upcall instead of adding the new upcall. 314 */ 315static inline struct gss_upcall_msg * 316gss_add_msg(struct gss_upcall_msg *gss_msg) 317{ 318 struct rpc_pipe *pipe = gss_msg->pipe; 319 struct gss_upcall_msg *old; 320 321 spin_lock(&pipe->lock); 322 old = __gss_find_upcall(pipe, gss_msg->uid); 323 if (old == NULL) { 324 atomic_inc(&gss_msg->count); 325 list_add(&gss_msg->list, &pipe->in_downcall); 326 } else 327 gss_msg = old; 328 spin_unlock(&pipe->lock); 329 return gss_msg; 330} 331 332static void 333__gss_unhash_msg(struct gss_upcall_msg *gss_msg) 334{ 335 list_del_init(&gss_msg->list); 336 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 337 wake_up_all(&gss_msg->waitqueue); 338 atomic_dec(&gss_msg->count); 339} 340 341static void 342gss_unhash_msg(struct gss_upcall_msg *gss_msg) 343{ 344 struct rpc_pipe *pipe = gss_msg->pipe; 345 346 if (list_empty(&gss_msg->list)) 347 return; 348 spin_lock(&pipe->lock); 349 if (!list_empty(&gss_msg->list)) 350 __gss_unhash_msg(gss_msg); 351 spin_unlock(&pipe->lock); 352} 353 354static void 355gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg) 356{ 357 switch (gss_msg->msg.errno) { 358 case 0: 359 if (gss_msg->ctx == NULL) 360 break; 361 clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 362 gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx); 363 break; 364 case -EKEYEXPIRED: 365 set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 366 } 367 gss_cred->gc_upcall_timestamp = jiffies; 368 gss_cred->gc_upcall = NULL; 369 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 370} 371 372static void 373gss_upcall_callback(struct rpc_task *task) 374{ 375 struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred, 376 struct gss_cred, gc_base); 377 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 378 struct rpc_pipe *pipe = gss_msg->pipe; 379 380 spin_lock(&pipe->lock); 381 gss_handle_downcall_result(gss_cred, gss_msg); 382 spin_unlock(&pipe->lock); 383 task->tk_status = gss_msg->msg.errno; 384 gss_release_msg(gss_msg); 385} 386 387static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 388{ 389 gss_msg->msg.data = &gss_msg->uid; 390 gss_msg->msg.len = sizeof(gss_msg->uid); 391} 392 393static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 394 struct rpc_clnt *clnt, 395 const char *service_name) 396{ 397 struct gss_api_mech *mech = gss_msg->auth->mech; 398 char *p = gss_msg->databuf; 399 int len = 0; 400 401 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ", 402 mech->gm_name, 403 gss_msg->uid); 404 p += gss_msg->msg.len; 405 if (clnt->cl_principal) { 406 len = sprintf(p, "target=%s ", clnt->cl_principal); 407 p += len; 408 gss_msg->msg.len += len; 409 } 410 if (service_name != NULL) { 411 len = sprintf(p, "service=%s ", service_name); 412 p += len; 413 gss_msg->msg.len += len; 414 } 415 if (mech->gm_upcall_enctypes) { 416 len = sprintf(p, "enctypes=%s ", mech->gm_upcall_enctypes); 417 p += len; 418 gss_msg->msg.len += len; 419 } 420 len = sprintf(p, "\n"); 421 gss_msg->msg.len += len; 422 423 gss_msg->msg.data = gss_msg->databuf; 424 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); 425} 426 427static void gss_encode_msg(struct gss_upcall_msg *gss_msg, 428 struct rpc_clnt *clnt, 429 const char *service_name) 430{ 431 if (pipe_version == 0) 432 gss_encode_v0_msg(gss_msg); 433 else /* pipe_version == 1 */ 434 gss_encode_v1_msg(gss_msg, clnt, service_name); 435} 436 437static struct gss_upcall_msg * 438gss_alloc_msg(struct gss_auth *gss_auth, struct rpc_clnt *clnt, 439 uid_t uid, const char *service_name) 440{ 441 struct gss_upcall_msg *gss_msg; 442 int vers; 443 444 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 445 if (gss_msg == NULL) 446 return ERR_PTR(-ENOMEM); 447 vers = get_pipe_version(); 448 if (vers < 0) { 449 kfree(gss_msg); 450 return ERR_PTR(vers); 451 } 452 gss_msg->pipe = gss_auth->pipe[vers]; 453 INIT_LIST_HEAD(&gss_msg->list); 454 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 455 init_waitqueue_head(&gss_msg->waitqueue); 456 atomic_set(&gss_msg->count, 1); 457 gss_msg->uid = uid; 458 gss_msg->auth = gss_auth; 459 gss_encode_msg(gss_msg, clnt, service_name); 460 return gss_msg; 461} 462 463static struct gss_upcall_msg * 464gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 465{ 466 struct gss_cred *gss_cred = container_of(cred, 467 struct gss_cred, gc_base); 468 struct gss_upcall_msg *gss_new, *gss_msg; 469 uid_t uid = cred->cr_uid; 470 471 gss_new = gss_alloc_msg(gss_auth, clnt, uid, gss_cred->gc_principal); 472 if (IS_ERR(gss_new)) 473 return gss_new; 474 gss_msg = gss_add_msg(gss_new); 475 if (gss_msg == gss_new) { 476 int res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg); 477 if (res) { 478 gss_unhash_msg(gss_new); 479 gss_msg = ERR_PTR(res); 480 } 481 } else 482 gss_release_msg(gss_new); 483 return gss_msg; 484} 485 486static void warn_gssd(void) 487{ 488 static unsigned long ratelimit; 489 unsigned long now = jiffies; 490 491 if (time_after(now, ratelimit)) { 492 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 493 "Please check user daemon is running.\n"); 494 ratelimit = now + 15*HZ; 495 } 496} 497 498static inline int 499gss_refresh_upcall(struct rpc_task *task) 500{ 501 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 502 struct gss_auth *gss_auth = container_of(cred->cr_auth, 503 struct gss_auth, rpc_auth); 504 struct gss_cred *gss_cred = container_of(cred, 505 struct gss_cred, gc_base); 506 struct gss_upcall_msg *gss_msg; 507 struct rpc_pipe *pipe; 508 int err = 0; 509 510 dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid, 511 cred->cr_uid); 512 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 513 if (PTR_ERR(gss_msg) == -EAGAIN) { 514 /* XXX: warning on the first, under the assumption we 515 * shouldn't normally hit this case on a refresh. */ 516 warn_gssd(); 517 task->tk_timeout = 15*HZ; 518 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 519 return -EAGAIN; 520 } 521 if (IS_ERR(gss_msg)) { 522 err = PTR_ERR(gss_msg); 523 goto out; 524 } 525 pipe = gss_msg->pipe; 526 spin_lock(&pipe->lock); 527 if (gss_cred->gc_upcall != NULL) 528 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 529 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { 530 task->tk_timeout = 0; 531 gss_cred->gc_upcall = gss_msg; 532 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 533 atomic_inc(&gss_msg->count); 534 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 535 } else { 536 gss_handle_downcall_result(gss_cred, gss_msg); 537 err = gss_msg->msg.errno; 538 } 539 spin_unlock(&pipe->lock); 540 gss_release_msg(gss_msg); 541out: 542 dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n", 543 task->tk_pid, cred->cr_uid, err); 544 return err; 545} 546 547static inline int 548gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 549{ 550 struct rpc_pipe *pipe; 551 struct rpc_cred *cred = &gss_cred->gc_base; 552 struct gss_upcall_msg *gss_msg; 553 DEFINE_WAIT(wait); 554 int err = 0; 555 556 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); 557retry: 558 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 559 if (PTR_ERR(gss_msg) == -EAGAIN) { 560 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 561 pipe_version >= 0, 15*HZ); 562 if (pipe_version < 0) { 563 warn_gssd(); 564 err = -EACCES; 565 } 566 if (err) 567 goto out; 568 goto retry; 569 } 570 if (IS_ERR(gss_msg)) { 571 err = PTR_ERR(gss_msg); 572 goto out; 573 } 574 pipe = gss_msg->pipe; 575 for (;;) { 576 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE); 577 spin_lock(&pipe->lock); 578 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 579 break; 580 } 581 spin_unlock(&pipe->lock); 582 if (fatal_signal_pending(current)) { 583 err = -ERESTARTSYS; 584 goto out_intr; 585 } 586 schedule(); 587 } 588 if (gss_msg->ctx) 589 gss_cred_set_ctx(cred, gss_msg->ctx); 590 else 591 err = gss_msg->msg.errno; 592 spin_unlock(&pipe->lock); 593out_intr: 594 finish_wait(&gss_msg->waitqueue, &wait); 595 gss_release_msg(gss_msg); 596out: 597 dprintk("RPC: gss_create_upcall for uid %u result %d\n", 598 cred->cr_uid, err); 599 return err; 600} 601 602#define MSG_BUF_MAXSIZE 1024 603 604static ssize_t 605gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 606{ 607 const void *p, *end; 608 void *buf; 609 struct gss_upcall_msg *gss_msg; 610 struct rpc_pipe *pipe = RPC_I(filp->f_dentry->d_inode)->pipe; 611 struct gss_cl_ctx *ctx; 612 uid_t uid; 613 ssize_t err = -EFBIG; 614 615 if (mlen > MSG_BUF_MAXSIZE) 616 goto out; 617 err = -ENOMEM; 618 buf = kmalloc(mlen, GFP_NOFS); 619 if (!buf) 620 goto out; 621 622 err = -EFAULT; 623 if (copy_from_user(buf, src, mlen)) 624 goto err; 625 626 end = (const void *)((char *)buf + mlen); 627 p = simple_get_bytes(buf, end, &uid, sizeof(uid)); 628 if (IS_ERR(p)) { 629 err = PTR_ERR(p); 630 goto err; 631 } 632 633 err = -ENOMEM; 634 ctx = gss_alloc_context(); 635 if (ctx == NULL) 636 goto err; 637 638 err = -ENOENT; 639 /* Find a matching upcall */ 640 spin_lock(&pipe->lock); 641 gss_msg = __gss_find_upcall(pipe, uid); 642 if (gss_msg == NULL) { 643 spin_unlock(&pipe->lock); 644 goto err_put_ctx; 645 } 646 list_del_init(&gss_msg->list); 647 spin_unlock(&pipe->lock); 648 649 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); 650 if (IS_ERR(p)) { 651 err = PTR_ERR(p); 652 switch (err) { 653 case -EACCES: 654 case -EKEYEXPIRED: 655 gss_msg->msg.errno = err; 656 err = mlen; 657 break; 658 case -EFAULT: 659 case -ENOMEM: 660 case -EINVAL: 661 case -ENOSYS: 662 gss_msg->msg.errno = -EAGAIN; 663 break; 664 default: 665 printk(KERN_CRIT "%s: bad return from " 666 "gss_fill_context: %zd\n", __func__, err); 667 BUG(); 668 } 669 goto err_release_msg; 670 } 671 gss_msg->ctx = gss_get_ctx(ctx); 672 err = mlen; 673 674err_release_msg: 675 spin_lock(&pipe->lock); 676 __gss_unhash_msg(gss_msg); 677 spin_unlock(&pipe->lock); 678 gss_release_msg(gss_msg); 679err_put_ctx: 680 gss_put_ctx(ctx); 681err: 682 kfree(buf); 683out: 684 dprintk("RPC: gss_pipe_downcall returning %Zd\n", err); 685 return err; 686} 687 688static int gss_pipe_open(struct inode *inode, int new_version) 689{ 690 int ret = 0; 691 692 spin_lock(&pipe_version_lock); 693 if (pipe_version < 0) { 694 /* First open of any gss pipe determines the version: */ 695 pipe_version = new_version; 696 rpc_wake_up(&pipe_version_rpc_waitqueue); 697 wake_up(&pipe_version_waitqueue); 698 } else if (pipe_version != new_version) { 699 /* Trying to open a pipe of a different version */ 700 ret = -EBUSY; 701 goto out; 702 } 703 atomic_inc(&pipe_users); 704out: 705 spin_unlock(&pipe_version_lock); 706 return ret; 707 708} 709 710static int gss_pipe_open_v0(struct inode *inode) 711{ 712 return gss_pipe_open(inode, 0); 713} 714 715static int gss_pipe_open_v1(struct inode *inode) 716{ 717 return gss_pipe_open(inode, 1); 718} 719 720static void 721gss_pipe_release(struct inode *inode) 722{ 723 struct rpc_pipe *pipe = RPC_I(inode)->pipe; 724 struct gss_upcall_msg *gss_msg; 725 726restart: 727 spin_lock(&pipe->lock); 728 list_for_each_entry(gss_msg, &pipe->in_downcall, list) { 729 730 if (!list_empty(&gss_msg->msg.list)) 731 continue; 732 gss_msg->msg.errno = -EPIPE; 733 atomic_inc(&gss_msg->count); 734 __gss_unhash_msg(gss_msg); 735 spin_unlock(&pipe->lock); 736 gss_release_msg(gss_msg); 737 goto restart; 738 } 739 spin_unlock(&pipe->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 760static void gss_pipes_dentries_destroy(struct rpc_auth *auth) 761{ 762 struct gss_auth *gss_auth; 763 764 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 765 if (gss_auth->pipe[0]->dentry) 766 rpc_unlink(gss_auth->pipe[0]->dentry); 767 if (gss_auth->pipe[1]->dentry) 768 rpc_unlink(gss_auth->pipe[1]->dentry); 769} 770 771static int gss_pipes_dentries_create(struct rpc_auth *auth) 772{ 773 int err; 774 struct gss_auth *gss_auth; 775 struct rpc_clnt *clnt; 776 777 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 778 clnt = gss_auth->client; 779 780 gss_auth->pipe[1]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry, 781 "gssd", 782 clnt, gss_auth->pipe[1]); 783 if (IS_ERR(gss_auth->pipe[1]->dentry)) 784 return PTR_ERR(gss_auth->pipe[1]->dentry); 785 gss_auth->pipe[0]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry, 786 gss_auth->mech->gm_name, 787 clnt, gss_auth->pipe[0]); 788 if (IS_ERR(gss_auth->pipe[0]->dentry)) { 789 err = PTR_ERR(gss_auth->pipe[0]->dentry); 790 goto err_unlink_pipe_1; 791 } 792 return 0; 793 794err_unlink_pipe_1: 795 rpc_unlink(gss_auth->pipe[1]->dentry); 796 return err; 797} 798 799static void gss_pipes_dentries_destroy_net(struct rpc_clnt *clnt, 800 struct rpc_auth *auth) 801{ 802 struct net *net = rpc_net_ns(clnt); 803 struct super_block *sb; 804 805 sb = rpc_get_sb_net(net); 806 if (sb) { 807 if (clnt->cl_dentry) 808 gss_pipes_dentries_destroy(auth); 809 rpc_put_sb_net(net); 810 } 811} 812 813static int gss_pipes_dentries_create_net(struct rpc_clnt *clnt, 814 struct rpc_auth *auth) 815{ 816 struct net *net = rpc_net_ns(clnt); 817 struct super_block *sb; 818 int err = 0; 819 820 sb = rpc_get_sb_net(net); 821 if (sb) { 822 if (clnt->cl_dentry) 823 err = gss_pipes_dentries_create(auth); 824 rpc_put_sb_net(net); 825 } 826 return err; 827} 828 829/* 830 * NOTE: we have the opportunity to use different 831 * parameters based on the input flavor (which must be a pseudoflavor) 832 */ 833static struct rpc_auth * 834gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 835{ 836 struct gss_auth *gss_auth; 837 struct rpc_auth * auth; 838 int err = -ENOMEM; /* XXX? */ 839 840 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 841 842 if (!try_module_get(THIS_MODULE)) 843 return ERR_PTR(err); 844 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 845 goto out_dec; 846 gss_auth->client = clnt; 847 err = -EINVAL; 848 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 849 if (!gss_auth->mech) { 850 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 851 __func__, flavor); 852 goto err_free; 853 } 854 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 855 if (gss_auth->service == 0) 856 goto err_put_mech; 857 auth = &gss_auth->rpc_auth; 858 auth->au_cslack = GSS_CRED_SLACK >> 2; 859 auth->au_rslack = GSS_VERF_SLACK >> 2; 860 auth->au_ops = &authgss_ops; 861 auth->au_flavor = flavor; 862 atomic_set(&auth->au_count, 1); 863 kref_init(&gss_auth->kref); 864 865 /* 866 * Note: if we created the old pipe first, then someone who 867 * examined the directory at the right moment might conclude 868 * that we supported only the old pipe. So we instead create 869 * the new pipe first. 870 */ 871 gss_auth->pipe[1] = rpc_mkpipe_data(&gss_upcall_ops_v1, 872 RPC_PIPE_WAIT_FOR_OPEN); 873 if (IS_ERR(gss_auth->pipe[1])) { 874 err = PTR_ERR(gss_auth->pipe[1]); 875 goto err_put_mech; 876 } 877 878 gss_auth->pipe[0] = rpc_mkpipe_data(&gss_upcall_ops_v0, 879 RPC_PIPE_WAIT_FOR_OPEN); 880 if (IS_ERR(gss_auth->pipe[0])) { 881 err = PTR_ERR(gss_auth->pipe[0]); 882 goto err_destroy_pipe_1; 883 } 884 err = gss_pipes_dentries_create_net(clnt, auth); 885 if (err) 886 goto err_destroy_pipe_0; 887 err = rpcauth_init_credcache(auth); 888 if (err) 889 goto err_unlink_pipes; 890 891 return auth; 892err_unlink_pipes: 893 gss_pipes_dentries_destroy_net(clnt, auth); 894err_destroy_pipe_0: 895 rpc_destroy_pipe_data(gss_auth->pipe[0]); 896err_destroy_pipe_1: 897 rpc_destroy_pipe_data(gss_auth->pipe[1]); 898err_put_mech: 899 gss_mech_put(gss_auth->mech); 900err_free: 901 kfree(gss_auth); 902out_dec: 903 module_put(THIS_MODULE); 904 return ERR_PTR(err); 905} 906 907static void 908gss_free(struct gss_auth *gss_auth) 909{ 910 gss_pipes_dentries_destroy_net(gss_auth->client, &gss_auth->rpc_auth); 911 rpc_destroy_pipe_data(gss_auth->pipe[0]); 912 rpc_destroy_pipe_data(gss_auth->pipe[1]); 913 gss_mech_put(gss_auth->mech); 914 915 kfree(gss_auth); 916 module_put(THIS_MODULE); 917} 918 919static void 920gss_free_callback(struct kref *kref) 921{ 922 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 923 924 gss_free(gss_auth); 925} 926 927static void 928gss_destroy(struct rpc_auth *auth) 929{ 930 struct gss_auth *gss_auth; 931 932 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 933 auth, auth->au_flavor); 934 935 rpcauth_destroy_credcache(auth); 936 937 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 938 kref_put(&gss_auth->kref, gss_free_callback); 939} 940 941/* 942 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 943 * to the server with the GSS control procedure field set to 944 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 945 * all RPCSEC_GSS state associated with that context. 946 */ 947static int 948gss_destroying_context(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 rpc_task *task; 953 954 if (gss_cred->gc_ctx == NULL || 955 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 956 return 0; 957 958 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 959 cred->cr_ops = &gss_nullops; 960 961 /* Take a reference to ensure the cred will be destroyed either 962 * by the RPC call or by the put_rpccred() below */ 963 get_rpccred(cred); 964 965 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 966 if (!IS_ERR(task)) 967 rpc_put_task(task); 968 969 put_rpccred(cred); 970 return 1; 971} 972 973/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 974 * to create a new cred or context, so they check that things have been 975 * allocated before freeing them. */ 976static void 977gss_do_free_ctx(struct gss_cl_ctx *ctx) 978{ 979 dprintk("RPC: gss_free_ctx\n"); 980 981 gss_delete_sec_context(&ctx->gc_gss_ctx); 982 kfree(ctx->gc_wire_ctx.data); 983 kfree(ctx); 984} 985 986static void 987gss_free_ctx_callback(struct rcu_head *head) 988{ 989 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 990 gss_do_free_ctx(ctx); 991} 992 993static void 994gss_free_ctx(struct gss_cl_ctx *ctx) 995{ 996 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 997} 998 999static void 1000gss_free_cred(struct gss_cred *gss_cred) 1001{ 1002 dprintk("RPC: gss_free_cred %p\n", gss_cred); 1003 kfree(gss_cred); 1004} 1005 1006static void 1007gss_free_cred_callback(struct rcu_head *head) 1008{ 1009 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 1010 gss_free_cred(gss_cred); 1011} 1012 1013static void 1014gss_destroy_nullcred(struct rpc_cred *cred) 1015{ 1016 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 1017 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 1018 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 1019 1020 RCU_INIT_POINTER(gss_cred->gc_ctx, NULL); 1021 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 1022 if (ctx) 1023 gss_put_ctx(ctx); 1024 kref_put(&gss_auth->kref, gss_free_callback); 1025} 1026 1027static void 1028gss_destroy_cred(struct rpc_cred *cred) 1029{ 1030 1031 if (gss_destroying_context(cred)) 1032 return; 1033 gss_destroy_nullcred(cred); 1034} 1035 1036/* 1037 * Lookup RPCSEC_GSS cred for the current process 1038 */ 1039static struct rpc_cred * 1040gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1041{ 1042 return rpcauth_lookup_credcache(auth, acred, flags); 1043} 1044 1045static struct rpc_cred * 1046gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1047{ 1048 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1049 struct gss_cred *cred = NULL; 1050 int err = -ENOMEM; 1051 1052 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 1053 acred->uid, auth->au_flavor); 1054 1055 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 1056 goto out_err; 1057 1058 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 1059 /* 1060 * Note: in order to force a call to call_refresh(), we deliberately 1061 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 1062 */ 1063 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 1064 cred->gc_service = gss_auth->service; 1065 cred->gc_principal = NULL; 1066 if (acred->machine_cred) 1067 cred->gc_principal = acred->principal; 1068 kref_get(&gss_auth->kref); 1069 return &cred->gc_base; 1070 1071out_err: 1072 dprintk("RPC: gss_create_cred failed with error %d\n", err); 1073 return ERR_PTR(err); 1074} 1075 1076static int 1077gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1078{ 1079 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1080 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1081 int err; 1082 1083 do { 1084 err = gss_create_upcall(gss_auth, gss_cred); 1085 } while (err == -EAGAIN); 1086 return err; 1087} 1088 1089static int 1090gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1091{ 1092 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1093 1094 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1095 goto out; 1096 /* Don't match with creds that have expired. */ 1097 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1098 return 0; 1099 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1100 return 0; 1101out: 1102 if (acred->principal != NULL) { 1103 if (gss_cred->gc_principal == NULL) 1104 return 0; 1105 return strcmp(acred->principal, gss_cred->gc_principal) == 0; 1106 } 1107 if (gss_cred->gc_principal != NULL) 1108 return 0; 1109 return rc->cr_uid == acred->uid; 1110} 1111 1112/* 1113* Marshal credentials. 1114* Maybe we should keep a cached credential for performance reasons. 1115*/ 1116static __be32 * 1117gss_marshal(struct rpc_task *task, __be32 *p) 1118{ 1119 struct rpc_rqst *req = task->tk_rqstp; 1120 struct rpc_cred *cred = req->rq_cred; 1121 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1122 gc_base); 1123 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1124 __be32 *cred_len; 1125 u32 maj_stat = 0; 1126 struct xdr_netobj mic; 1127 struct kvec iov; 1128 struct xdr_buf verf_buf; 1129 1130 dprintk("RPC: %5u gss_marshal\n", task->tk_pid); 1131 1132 *p++ = htonl(RPC_AUTH_GSS); 1133 cred_len = p++; 1134 1135 spin_lock(&ctx->gc_seq_lock); 1136 req->rq_seqno = ctx->gc_seq++; 1137 spin_unlock(&ctx->gc_seq_lock); 1138 1139 *p++ = htonl((u32) RPC_GSS_VERSION); 1140 *p++ = htonl((u32) ctx->gc_proc); 1141 *p++ = htonl((u32) req->rq_seqno); 1142 *p++ = htonl((u32) gss_cred->gc_service); 1143 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1144 *cred_len = htonl((p - (cred_len + 1)) << 2); 1145 1146 /* We compute the checksum for the verifier over the xdr-encoded bytes 1147 * starting with the xid and ending at the end of the credential: */ 1148 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 1149 req->rq_snd_buf.head[0].iov_base); 1150 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1151 xdr_buf_from_iov(&iov, &verf_buf); 1152 1153 /* set verifier flavor*/ 1154 *p++ = htonl(RPC_AUTH_GSS); 1155 1156 mic.data = (u8 *)(p + 1); 1157 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1158 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1159 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1160 } else if (maj_stat != 0) { 1161 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1162 goto out_put_ctx; 1163 } 1164 p = xdr_encode_opaque(p, NULL, mic.len); 1165 gss_put_ctx(ctx); 1166 return p; 1167out_put_ctx: 1168 gss_put_ctx(ctx); 1169 return NULL; 1170} 1171 1172static int gss_renew_cred(struct rpc_task *task) 1173{ 1174 struct rpc_cred *oldcred = task->tk_rqstp->rq_cred; 1175 struct gss_cred *gss_cred = container_of(oldcred, 1176 struct gss_cred, 1177 gc_base); 1178 struct rpc_auth *auth = oldcred->cr_auth; 1179 struct auth_cred acred = { 1180 .uid = oldcred->cr_uid, 1181 .principal = gss_cred->gc_principal, 1182 .machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0), 1183 }; 1184 struct rpc_cred *new; 1185 1186 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1187 if (IS_ERR(new)) 1188 return PTR_ERR(new); 1189 task->tk_rqstp->rq_cred = new; 1190 put_rpccred(oldcred); 1191 return 0; 1192} 1193 1194static int gss_cred_is_negative_entry(struct rpc_cred *cred) 1195{ 1196 if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) { 1197 unsigned long now = jiffies; 1198 unsigned long begin, expire; 1199 struct gss_cred *gss_cred; 1200 1201 gss_cred = container_of(cred, struct gss_cred, gc_base); 1202 begin = gss_cred->gc_upcall_timestamp; 1203 expire = begin + gss_expired_cred_retry_delay * HZ; 1204 1205 if (time_in_range_open(now, begin, expire)) 1206 return 1; 1207 } 1208 return 0; 1209} 1210 1211/* 1212* Refresh credentials. XXX - finish 1213*/ 1214static int 1215gss_refresh(struct rpc_task *task) 1216{ 1217 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1218 int ret = 0; 1219 1220 if (gss_cred_is_negative_entry(cred)) 1221 return -EKEYEXPIRED; 1222 1223 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1224 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1225 ret = gss_renew_cred(task); 1226 if (ret < 0) 1227 goto out; 1228 cred = task->tk_rqstp->rq_cred; 1229 } 1230 1231 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1232 ret = gss_refresh_upcall(task); 1233out: 1234 return ret; 1235} 1236 1237/* Dummy refresh routine: used only when destroying the context */ 1238static int 1239gss_refresh_null(struct rpc_task *task) 1240{ 1241 return -EACCES; 1242} 1243 1244static __be32 * 1245gss_validate(struct rpc_task *task, __be32 *p) 1246{ 1247 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1248 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1249 __be32 seq; 1250 struct kvec iov; 1251 struct xdr_buf verf_buf; 1252 struct xdr_netobj mic; 1253 u32 flav,len; 1254 u32 maj_stat; 1255 1256 dprintk("RPC: %5u gss_validate\n", task->tk_pid); 1257 1258 flav = ntohl(*p++); 1259 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1260 goto out_bad; 1261 if (flav != RPC_AUTH_GSS) 1262 goto out_bad; 1263 seq = htonl(task->tk_rqstp->rq_seqno); 1264 iov.iov_base = &seq; 1265 iov.iov_len = sizeof(seq); 1266 xdr_buf_from_iov(&iov, &verf_buf); 1267 mic.data = (u8 *)p; 1268 mic.len = len; 1269 1270 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1271 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1272 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1273 if (maj_stat) { 1274 dprintk("RPC: %5u gss_validate: gss_verify_mic returned " 1275 "error 0x%08x\n", task->tk_pid, maj_stat); 1276 goto out_bad; 1277 } 1278 /* We leave it to unwrap to calculate au_rslack. For now we just 1279 * calculate the length of the verifier: */ 1280 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1281 gss_put_ctx(ctx); 1282 dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n", 1283 task->tk_pid); 1284 return p + XDR_QUADLEN(len); 1285out_bad: 1286 gss_put_ctx(ctx); 1287 dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid); 1288 return NULL; 1289} 1290 1291static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp, 1292 __be32 *p, void *obj) 1293{ 1294 struct xdr_stream xdr; 1295 1296 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, p); 1297 encode(rqstp, &xdr, obj); 1298} 1299 1300static inline int 1301gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1302 kxdreproc_t encode, struct rpc_rqst *rqstp, 1303 __be32 *p, void *obj) 1304{ 1305 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1306 struct xdr_buf integ_buf; 1307 __be32 *integ_len = NULL; 1308 struct xdr_netobj mic; 1309 u32 offset; 1310 __be32 *q; 1311 struct kvec *iov; 1312 u32 maj_stat = 0; 1313 int status = -EIO; 1314 1315 integ_len = p++; 1316 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1317 *p++ = htonl(rqstp->rq_seqno); 1318 1319 gss_wrap_req_encode(encode, rqstp, p, obj); 1320 1321 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1322 offset, snd_buf->len - offset)) 1323 return status; 1324 *integ_len = htonl(integ_buf.len); 1325 1326 /* guess whether we're in the head or the tail: */ 1327 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1328 iov = snd_buf->tail; 1329 else 1330 iov = snd_buf->head; 1331 p = iov->iov_base + iov->iov_len; 1332 mic.data = (u8 *)(p + 1); 1333 1334 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1335 status = -EIO; /* XXX? */ 1336 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1337 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1338 else if (maj_stat) 1339 return status; 1340 q = xdr_encode_opaque(p, NULL, mic.len); 1341 1342 offset = (u8 *)q - (u8 *)p; 1343 iov->iov_len += offset; 1344 snd_buf->len += offset; 1345 return 0; 1346} 1347 1348static void 1349priv_release_snd_buf(struct rpc_rqst *rqstp) 1350{ 1351 int i; 1352 1353 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1354 __free_page(rqstp->rq_enc_pages[i]); 1355 kfree(rqstp->rq_enc_pages); 1356} 1357 1358static int 1359alloc_enc_pages(struct rpc_rqst *rqstp) 1360{ 1361 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1362 int first, last, i; 1363 1364 if (snd_buf->page_len == 0) { 1365 rqstp->rq_enc_pages_num = 0; 1366 return 0; 1367 } 1368 1369 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1370 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1371 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1372 rqstp->rq_enc_pages 1373 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1374 GFP_NOFS); 1375 if (!rqstp->rq_enc_pages) 1376 goto out; 1377 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1378 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1379 if (rqstp->rq_enc_pages[i] == NULL) 1380 goto out_free; 1381 } 1382 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1383 return 0; 1384out_free: 1385 rqstp->rq_enc_pages_num = i; 1386 priv_release_snd_buf(rqstp); 1387out: 1388 return -EAGAIN; 1389} 1390 1391static inline int 1392gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1393 kxdreproc_t encode, struct rpc_rqst *rqstp, 1394 __be32 *p, void *obj) 1395{ 1396 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1397 u32 offset; 1398 u32 maj_stat; 1399 int status; 1400 __be32 *opaque_len; 1401 struct page **inpages; 1402 int first; 1403 int pad; 1404 struct kvec *iov; 1405 char *tmp; 1406 1407 opaque_len = p++; 1408 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1409 *p++ = htonl(rqstp->rq_seqno); 1410 1411 gss_wrap_req_encode(encode, rqstp, p, obj); 1412 1413 status = alloc_enc_pages(rqstp); 1414 if (status) 1415 return status; 1416 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1417 inpages = snd_buf->pages + first; 1418 snd_buf->pages = rqstp->rq_enc_pages; 1419 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1420 /* 1421 * Give the tail its own page, in case we need extra space in the 1422 * head when wrapping: 1423 * 1424 * call_allocate() allocates twice the slack space required 1425 * by the authentication flavor to rq_callsize. 1426 * For GSS, slack is GSS_CRED_SLACK. 1427 */ 1428 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1429 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1430 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1431 snd_buf->tail[0].iov_base = tmp; 1432 } 1433 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1434 /* slack space should prevent this ever happening: */ 1435 BUG_ON(snd_buf->len > snd_buf->buflen); 1436 status = -EIO; 1437 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1438 * done anyway, so it's safe to put the request on the wire: */ 1439 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1440 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1441 else if (maj_stat) 1442 return status; 1443 1444 *opaque_len = htonl(snd_buf->len - offset); 1445 /* guess whether we're in the head or the tail: */ 1446 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1447 iov = snd_buf->tail; 1448 else 1449 iov = snd_buf->head; 1450 p = iov->iov_base + iov->iov_len; 1451 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1452 memset(p, 0, pad); 1453 iov->iov_len += pad; 1454 snd_buf->len += pad; 1455 1456 return 0; 1457} 1458 1459static int 1460gss_wrap_req(struct rpc_task *task, 1461 kxdreproc_t encode, void *rqstp, __be32 *p, void *obj) 1462{ 1463 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1464 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1465 gc_base); 1466 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1467 int status = -EIO; 1468 1469 dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid); 1470 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1471 /* The spec seems a little ambiguous here, but I think that not 1472 * wrapping context destruction requests makes the most sense. 1473 */ 1474 gss_wrap_req_encode(encode, rqstp, p, obj); 1475 status = 0; 1476 goto out; 1477 } 1478 switch (gss_cred->gc_service) { 1479 case RPC_GSS_SVC_NONE: 1480 gss_wrap_req_encode(encode, rqstp, p, obj); 1481 status = 0; 1482 break; 1483 case RPC_GSS_SVC_INTEGRITY: 1484 status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj); 1485 break; 1486 case RPC_GSS_SVC_PRIVACY: 1487 status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj); 1488 break; 1489 } 1490out: 1491 gss_put_ctx(ctx); 1492 dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status); 1493 return status; 1494} 1495 1496static inline int 1497gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1498 struct rpc_rqst *rqstp, __be32 **p) 1499{ 1500 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1501 struct xdr_buf integ_buf; 1502 struct xdr_netobj mic; 1503 u32 data_offset, mic_offset; 1504 u32 integ_len; 1505 u32 maj_stat; 1506 int status = -EIO; 1507 1508 integ_len = ntohl(*(*p)++); 1509 if (integ_len & 3) 1510 return status; 1511 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1512 mic_offset = integ_len + data_offset; 1513 if (mic_offset > rcv_buf->len) 1514 return status; 1515 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1516 return status; 1517 1518 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1519 mic_offset - data_offset)) 1520 return status; 1521 1522 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1523 return status; 1524 1525 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1526 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1527 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1528 if (maj_stat != GSS_S_COMPLETE) 1529 return status; 1530 return 0; 1531} 1532 1533static inline int 1534gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1535 struct rpc_rqst *rqstp, __be32 **p) 1536{ 1537 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1538 u32 offset; 1539 u32 opaque_len; 1540 u32 maj_stat; 1541 int status = -EIO; 1542 1543 opaque_len = ntohl(*(*p)++); 1544 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1545 if (offset + opaque_len > rcv_buf->len) 1546 return status; 1547 /* remove padding: */ 1548 rcv_buf->len = offset + opaque_len; 1549 1550 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1551 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1552 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1553 if (maj_stat != GSS_S_COMPLETE) 1554 return status; 1555 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1556 return status; 1557 1558 return 0; 1559} 1560 1561static int 1562gss_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp, 1563 __be32 *p, void *obj) 1564{ 1565 struct xdr_stream xdr; 1566 1567 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); 1568 return decode(rqstp, &xdr, obj); 1569} 1570 1571static int 1572gss_unwrap_resp(struct rpc_task *task, 1573 kxdrdproc_t decode, void *rqstp, __be32 *p, void *obj) 1574{ 1575 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1576 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1577 gc_base); 1578 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1579 __be32 *savedp = p; 1580 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1581 int savedlen = head->iov_len; 1582 int status = -EIO; 1583 1584 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1585 goto out_decode; 1586 switch (gss_cred->gc_service) { 1587 case RPC_GSS_SVC_NONE: 1588 break; 1589 case RPC_GSS_SVC_INTEGRITY: 1590 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1591 if (status) 1592 goto out; 1593 break; 1594 case RPC_GSS_SVC_PRIVACY: 1595 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1596 if (status) 1597 goto out; 1598 break; 1599 } 1600 /* take into account extra slack for integrity and privacy cases: */ 1601 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1602 + (savedlen - head->iov_len); 1603out_decode: 1604 status = gss_unwrap_req_decode(decode, rqstp, p, obj); 1605out: 1606 gss_put_ctx(ctx); 1607 dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid, 1608 status); 1609 return status; 1610} 1611 1612static const struct rpc_authops authgss_ops = { 1613 .owner = THIS_MODULE, 1614 .au_flavor = RPC_AUTH_GSS, 1615 .au_name = "RPCSEC_GSS", 1616 .create = gss_create, 1617 .destroy = gss_destroy, 1618 .lookup_cred = gss_lookup_cred, 1619 .crcreate = gss_create_cred, 1620 .pipes_create = gss_pipes_dentries_create, 1621 .pipes_destroy = gss_pipes_dentries_destroy, 1622}; 1623 1624static const struct rpc_credops gss_credops = { 1625 .cr_name = "AUTH_GSS", 1626 .crdestroy = gss_destroy_cred, 1627 .cr_init = gss_cred_init, 1628 .crbind = rpcauth_generic_bind_cred, 1629 .crmatch = gss_match, 1630 .crmarshal = gss_marshal, 1631 .crrefresh = gss_refresh, 1632 .crvalidate = gss_validate, 1633 .crwrap_req = gss_wrap_req, 1634 .crunwrap_resp = gss_unwrap_resp, 1635}; 1636 1637static const struct rpc_credops gss_nullops = { 1638 .cr_name = "AUTH_GSS", 1639 .crdestroy = gss_destroy_nullcred, 1640 .crbind = rpcauth_generic_bind_cred, 1641 .crmatch = gss_match, 1642 .crmarshal = gss_marshal, 1643 .crrefresh = gss_refresh_null, 1644 .crvalidate = gss_validate, 1645 .crwrap_req = gss_wrap_req, 1646 .crunwrap_resp = gss_unwrap_resp, 1647}; 1648 1649static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 1650 .upcall = rpc_pipe_generic_upcall, 1651 .downcall = gss_pipe_downcall, 1652 .destroy_msg = gss_pipe_destroy_msg, 1653 .open_pipe = gss_pipe_open_v0, 1654 .release_pipe = gss_pipe_release, 1655}; 1656 1657static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 1658 .upcall = rpc_pipe_generic_upcall, 1659 .downcall = gss_pipe_downcall, 1660 .destroy_msg = gss_pipe_destroy_msg, 1661 .open_pipe = gss_pipe_open_v1, 1662 .release_pipe = gss_pipe_release, 1663}; 1664 1665static __net_init int rpcsec_gss_init_net(struct net *net) 1666{ 1667 return gss_svc_init_net(net); 1668} 1669 1670static __net_exit void rpcsec_gss_exit_net(struct net *net) 1671{ 1672 gss_svc_shutdown_net(net); 1673} 1674 1675static struct pernet_operations rpcsec_gss_net_ops = { 1676 .init = rpcsec_gss_init_net, 1677 .exit = rpcsec_gss_exit_net, 1678}; 1679 1680/* 1681 * Initialize RPCSEC_GSS module 1682 */ 1683static int __init init_rpcsec_gss(void) 1684{ 1685 int err = 0; 1686 1687 err = rpcauth_register(&authgss_ops); 1688 if (err) 1689 goto out; 1690 err = gss_svc_init(); 1691 if (err) 1692 goto out_unregister; 1693 err = register_pernet_subsys(&rpcsec_gss_net_ops); 1694 if (err) 1695 goto out_svc_exit; 1696 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1697 return 0; 1698out_svc_exit: 1699 gss_svc_shutdown(); 1700out_unregister: 1701 rpcauth_unregister(&authgss_ops); 1702out: 1703 return err; 1704} 1705 1706static void __exit exit_rpcsec_gss(void) 1707{ 1708 unregister_pernet_subsys(&rpcsec_gss_net_ops); 1709 gss_svc_shutdown(); 1710 rpcauth_unregister(&authgss_ops); 1711 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1712} 1713 1714MODULE_LICENSE("GPL"); 1715module_param_named(expired_cred_retry_delay, 1716 gss_expired_cred_retry_delay, 1717 uint, 0644); 1718MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until " 1719 "the RPC engine retries an expired credential"); 1720 1721module_init(init_rpcsec_gss) 1722module_exit(exit_rpcsec_gss) 1723