1 /* 2 * linux/net/sunrpc/auth_gss/auth_gss.c 3 * 4 * RPCSEC_GSS client authentication. 5 * 6 * Copyright (c) 2000 The Regents of the University of Michigan. 7 * All rights reserved. 8 * 9 * Dug Song <dugsong@monkey.org> 10 * Andy Adamson <andros@umich.edu> 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its 22 * contributors may be used to endorse or promote products derived 23 * from this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 26 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 27 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 28 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 32 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 33 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 34 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 39 #include <linux/module.h> 40 #include <linux/init.h> 41 #include <linux/types.h> 42 #include <linux/slab.h> 43 #include <linux/sched.h> 44 #include <linux/pagemap.h> 45 #include <linux/sunrpc/clnt.h> 46 #include <linux/sunrpc/auth.h> 47 #include <linux/sunrpc/auth_gss.h> 48 #include <linux/sunrpc/svcauth_gss.h> 49 #include <linux/sunrpc/gss_err.h> 50 #include <linux/workqueue.h> 51 #include <linux/sunrpc/rpc_pipe_fs.h> 52 #include <linux/sunrpc/gss_api.h> 53 #include <asm/uaccess.h> 54 #include <linux/hashtable.h> 55 56 #include "../netns.h" 57 58 static const struct rpc_authops authgss_ops; 59 60 static const struct rpc_credops gss_credops; 61 static const struct rpc_credops gss_nullops; 62 63 #define GSS_RETRY_EXPIRED 5 64 static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED; 65 66 #define GSS_KEY_EXPIRE_TIMEO 240 67 static unsigned int gss_key_expire_timeo = GSS_KEY_EXPIRE_TIMEO; 68 69 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 70 # define RPCDBG_FACILITY RPCDBG_AUTH 71 #endif 72 73 #define GSS_CRED_SLACK (RPC_MAX_AUTH_SIZE * 2) 74 /* length of a krb5 verifier (48), plus data added before arguments when 75 * using integrity (two 4-byte integers): */ 76 #define GSS_VERF_SLACK 100 77 78 static DEFINE_HASHTABLE(gss_auth_hash_table, 4); 79 static DEFINE_SPINLOCK(gss_auth_hash_lock); 80 81 struct gss_pipe { 82 struct rpc_pipe_dir_object pdo; 83 struct rpc_pipe *pipe; 84 struct rpc_clnt *clnt; 85 const char *name; 86 struct kref kref; 87 }; 88 89 struct gss_auth { 90 struct kref kref; 91 struct hlist_node hash; 92 struct rpc_auth rpc_auth; 93 struct gss_api_mech *mech; 94 enum rpc_gss_svc service; 95 struct rpc_clnt *client; 96 struct net *net; 97 /* 98 * There are two upcall pipes; dentry[1], named "gssd", is used 99 * for the new text-based upcall; dentry[0] is named after the 100 * mechanism (for example, "krb5") and exists for 101 * backwards-compatibility with older gssd's. 102 */ 103 struct gss_pipe *gss_pipe[2]; 104 const char *target_name; 105 }; 106 107 /* pipe_version >= 0 if and only if someone has a pipe open. */ 108 static DEFINE_SPINLOCK(pipe_version_lock); 109 static struct rpc_wait_queue pipe_version_rpc_waitqueue; 110 static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue); 111 static void gss_put_auth(struct gss_auth *gss_auth); 112 113 static void gss_free_ctx(struct gss_cl_ctx *); 114 static const struct rpc_pipe_ops gss_upcall_ops_v0; 115 static const struct rpc_pipe_ops gss_upcall_ops_v1; 116 117 static inline struct gss_cl_ctx * 118 gss_get_ctx(struct gss_cl_ctx *ctx) 119 { 120 atomic_inc(&ctx->count); 121 return ctx; 122 } 123 124 static inline void 125 gss_put_ctx(struct gss_cl_ctx *ctx) 126 { 127 if (atomic_dec_and_test(&ctx->count)) 128 gss_free_ctx(ctx); 129 } 130 131 /* gss_cred_set_ctx: 132 * called by gss_upcall_callback and gss_create_upcall in order 133 * to set the gss context. The actual exchange of an old context 134 * and a new one is protected by the pipe->lock. 135 */ 136 static void 137 gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) 138 { 139 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 140 141 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 142 return; 143 gss_get_ctx(ctx); 144 rcu_assign_pointer(gss_cred->gc_ctx, ctx); 145 set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 146 smp_mb__before_atomic(); 147 clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags); 148 } 149 150 static const void * 151 simple_get_bytes(const void *p, const void *end, void *res, size_t len) 152 { 153 const void *q = (const void *)((const char *)p + len); 154 if (unlikely(q > end || q < p)) 155 return ERR_PTR(-EFAULT); 156 memcpy(res, p, len); 157 return q; 158 } 159 160 static inline const void * 161 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) 162 { 163 const void *q; 164 unsigned int len; 165 166 p = simple_get_bytes(p, end, &len, sizeof(len)); 167 if (IS_ERR(p)) 168 return p; 169 q = (const void *)((const char *)p + len); 170 if (unlikely(q > end || q < p)) 171 return ERR_PTR(-EFAULT); 172 dest->data = kmemdup(p, len, GFP_NOFS); 173 if (unlikely(dest->data == NULL)) 174 return ERR_PTR(-ENOMEM); 175 dest->len = len; 176 return q; 177 } 178 179 static struct gss_cl_ctx * 180 gss_cred_get_ctx(struct rpc_cred *cred) 181 { 182 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 183 struct gss_cl_ctx *ctx = NULL; 184 185 rcu_read_lock(); 186 ctx = rcu_dereference(gss_cred->gc_ctx); 187 if (ctx) 188 gss_get_ctx(ctx); 189 rcu_read_unlock(); 190 return ctx; 191 } 192 193 static struct gss_cl_ctx * 194 gss_alloc_context(void) 195 { 196 struct gss_cl_ctx *ctx; 197 198 ctx = kzalloc(sizeof(*ctx), GFP_NOFS); 199 if (ctx != NULL) { 200 ctx->gc_proc = RPC_GSS_PROC_DATA; 201 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ 202 spin_lock_init(&ctx->gc_seq_lock); 203 atomic_set(&ctx->count,1); 204 } 205 return ctx; 206 } 207 208 #define GSSD_MIN_TIMEOUT (60 * 60) 209 static const void * 210 gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) 211 { 212 const void *q; 213 unsigned int seclen; 214 unsigned int timeout; 215 unsigned long now = jiffies; 216 u32 window_size; 217 int ret; 218 219 /* First unsigned int gives the remaining lifetime in seconds of the 220 * credential - e.g. the remaining TGT lifetime for Kerberos or 221 * the -t value passed to GSSD. 222 */ 223 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 224 if (IS_ERR(p)) 225 goto err; 226 if (timeout == 0) 227 timeout = GSSD_MIN_TIMEOUT; 228 ctx->gc_expiry = now + ((unsigned long)timeout * HZ); 229 /* Sequence number window. Determines the maximum number of 230 * simultaneous requests 231 */ 232 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 233 if (IS_ERR(p)) 234 goto err; 235 ctx->gc_win = window_size; 236 /* gssd signals an error by passing ctx->gc_win = 0: */ 237 if (ctx->gc_win == 0) { 238 /* 239 * in which case, p points to an error code. Anything other 240 * than -EKEYEXPIRED gets converted to -EACCES. 241 */ 242 p = simple_get_bytes(p, end, &ret, sizeof(ret)); 243 if (!IS_ERR(p)) 244 p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) : 245 ERR_PTR(-EACCES); 246 goto err; 247 } 248 /* copy the opaque wire context */ 249 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 250 if (IS_ERR(p)) 251 goto err; 252 /* import the opaque security context */ 253 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 254 if (IS_ERR(p)) 255 goto err; 256 q = (const void *)((const char *)p + seclen); 257 if (unlikely(q > end || q < p)) { 258 p = ERR_PTR(-EFAULT); 259 goto err; 260 } 261 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, NULL, GFP_NOFS); 262 if (ret < 0) { 263 p = ERR_PTR(ret); 264 goto err; 265 } 266 267 /* is there any trailing data? */ 268 if (q == end) { 269 p = q; 270 goto done; 271 } 272 273 /* pull in acceptor name (if there is one) */ 274 p = simple_get_netobj(q, end, &ctx->gc_acceptor); 275 if (IS_ERR(p)) 276 goto err; 277 done: 278 dprintk("RPC: %s Success. gc_expiry %lu now %lu timeout %u acceptor %.*s\n", 279 __func__, ctx->gc_expiry, now, timeout, ctx->gc_acceptor.len, 280 ctx->gc_acceptor.data); 281 return p; 282 err: 283 dprintk("RPC: %s returns error %ld\n", __func__, -PTR_ERR(p)); 284 return p; 285 } 286 287 #define UPCALL_BUF_LEN 128 288 289 struct gss_upcall_msg { 290 atomic_t count; 291 kuid_t uid; 292 struct rpc_pipe_msg msg; 293 struct list_head list; 294 struct gss_auth *auth; 295 struct rpc_pipe *pipe; 296 struct rpc_wait_queue rpc_waitqueue; 297 wait_queue_head_t waitqueue; 298 struct gss_cl_ctx *ctx; 299 char databuf[UPCALL_BUF_LEN]; 300 }; 301 302 static int get_pipe_version(struct net *net) 303 { 304 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 305 int ret; 306 307 spin_lock(&pipe_version_lock); 308 if (sn->pipe_version >= 0) { 309 atomic_inc(&sn->pipe_users); 310 ret = sn->pipe_version; 311 } else 312 ret = -EAGAIN; 313 spin_unlock(&pipe_version_lock); 314 return ret; 315 } 316 317 static void put_pipe_version(struct net *net) 318 { 319 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 320 321 if (atomic_dec_and_lock(&sn->pipe_users, &pipe_version_lock)) { 322 sn->pipe_version = -1; 323 spin_unlock(&pipe_version_lock); 324 } 325 } 326 327 static void 328 gss_release_msg(struct gss_upcall_msg *gss_msg) 329 { 330 struct net *net = gss_msg->auth->net; 331 if (!atomic_dec_and_test(&gss_msg->count)) 332 return; 333 put_pipe_version(net); 334 BUG_ON(!list_empty(&gss_msg->list)); 335 if (gss_msg->ctx != NULL) 336 gss_put_ctx(gss_msg->ctx); 337 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue); 338 gss_put_auth(gss_msg->auth); 339 kfree(gss_msg); 340 } 341 342 static struct gss_upcall_msg * 343 __gss_find_upcall(struct rpc_pipe *pipe, kuid_t uid) 344 { 345 struct gss_upcall_msg *pos; 346 list_for_each_entry(pos, &pipe->in_downcall, list) { 347 if (!uid_eq(pos->uid, uid)) 348 continue; 349 atomic_inc(&pos->count); 350 dprintk("RPC: %s found msg %p\n", __func__, pos); 351 return pos; 352 } 353 dprintk("RPC: %s found nothing\n", __func__); 354 return NULL; 355 } 356 357 /* Try to add an upcall to the pipefs queue. 358 * If an upcall owned by our uid already exists, then we return a reference 359 * to that upcall instead of adding the new upcall. 360 */ 361 static inline struct gss_upcall_msg * 362 gss_add_msg(struct gss_upcall_msg *gss_msg) 363 { 364 struct rpc_pipe *pipe = gss_msg->pipe; 365 struct gss_upcall_msg *old; 366 367 spin_lock(&pipe->lock); 368 old = __gss_find_upcall(pipe, gss_msg->uid); 369 if (old == NULL) { 370 atomic_inc(&gss_msg->count); 371 list_add(&gss_msg->list, &pipe->in_downcall); 372 } else 373 gss_msg = old; 374 spin_unlock(&pipe->lock); 375 return gss_msg; 376 } 377 378 static void 379 __gss_unhash_msg(struct gss_upcall_msg *gss_msg) 380 { 381 list_del_init(&gss_msg->list); 382 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 383 wake_up_all(&gss_msg->waitqueue); 384 atomic_dec(&gss_msg->count); 385 } 386 387 static void 388 gss_unhash_msg(struct gss_upcall_msg *gss_msg) 389 { 390 struct rpc_pipe *pipe = gss_msg->pipe; 391 392 if (list_empty(&gss_msg->list)) 393 return; 394 spin_lock(&pipe->lock); 395 if (!list_empty(&gss_msg->list)) 396 __gss_unhash_msg(gss_msg); 397 spin_unlock(&pipe->lock); 398 } 399 400 static void 401 gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg) 402 { 403 switch (gss_msg->msg.errno) { 404 case 0: 405 if (gss_msg->ctx == NULL) 406 break; 407 clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 408 gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx); 409 break; 410 case -EKEYEXPIRED: 411 set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 412 } 413 gss_cred->gc_upcall_timestamp = jiffies; 414 gss_cred->gc_upcall = NULL; 415 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 416 } 417 418 static void 419 gss_upcall_callback(struct rpc_task *task) 420 { 421 struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred, 422 struct gss_cred, gc_base); 423 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 424 struct rpc_pipe *pipe = gss_msg->pipe; 425 426 spin_lock(&pipe->lock); 427 gss_handle_downcall_result(gss_cred, gss_msg); 428 spin_unlock(&pipe->lock); 429 task->tk_status = gss_msg->msg.errno; 430 gss_release_msg(gss_msg); 431 } 432 433 static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 434 { 435 uid_t uid = from_kuid(&init_user_ns, gss_msg->uid); 436 memcpy(gss_msg->databuf, &uid, sizeof(uid)); 437 gss_msg->msg.data = gss_msg->databuf; 438 gss_msg->msg.len = sizeof(uid); 439 440 BUILD_BUG_ON(sizeof(uid) > sizeof(gss_msg->databuf)); 441 } 442 443 static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 444 const char *service_name, 445 const char *target_name) 446 { 447 struct gss_api_mech *mech = gss_msg->auth->mech; 448 char *p = gss_msg->databuf; 449 size_t buflen = sizeof(gss_msg->databuf); 450 int len; 451 452 len = scnprintf(p, buflen, "mech=%s uid=%d ", mech->gm_name, 453 from_kuid(&init_user_ns, gss_msg->uid)); 454 buflen -= len; 455 p += len; 456 gss_msg->msg.len = len; 457 if (target_name) { 458 len = scnprintf(p, buflen, "target=%s ", target_name); 459 buflen -= len; 460 p += len; 461 gss_msg->msg.len += len; 462 } 463 if (service_name != NULL) { 464 len = scnprintf(p, buflen, "service=%s ", service_name); 465 buflen -= len; 466 p += len; 467 gss_msg->msg.len += len; 468 } 469 if (mech->gm_upcall_enctypes) { 470 len = scnprintf(p, buflen, "enctypes=%s ", 471 mech->gm_upcall_enctypes); 472 buflen -= len; 473 p += len; 474 gss_msg->msg.len += len; 475 } 476 len = scnprintf(p, buflen, "\n"); 477 if (len == 0) 478 goto out_overflow; 479 gss_msg->msg.len += len; 480 481 gss_msg->msg.data = gss_msg->databuf; 482 return 0; 483 out_overflow: 484 WARN_ON_ONCE(1); 485 return -ENOMEM; 486 } 487 488 static struct gss_upcall_msg * 489 gss_alloc_msg(struct gss_auth *gss_auth, 490 kuid_t uid, const char *service_name) 491 { 492 struct gss_upcall_msg *gss_msg; 493 int vers; 494 int err = -ENOMEM; 495 496 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 497 if (gss_msg == NULL) 498 goto err; 499 vers = get_pipe_version(gss_auth->net); 500 err = vers; 501 if (err < 0) 502 goto err_free_msg; 503 gss_msg->pipe = gss_auth->gss_pipe[vers]->pipe; 504 INIT_LIST_HEAD(&gss_msg->list); 505 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 506 init_waitqueue_head(&gss_msg->waitqueue); 507 atomic_set(&gss_msg->count, 1); 508 gss_msg->uid = uid; 509 gss_msg->auth = gss_auth; 510 switch (vers) { 511 case 0: 512 gss_encode_v0_msg(gss_msg); 513 break; 514 default: 515 err = gss_encode_v1_msg(gss_msg, service_name, gss_auth->target_name); 516 if (err) 517 goto err_put_pipe_version; 518 }; 519 kref_get(&gss_auth->kref); 520 return gss_msg; 521 err_put_pipe_version: 522 put_pipe_version(gss_auth->net); 523 err_free_msg: 524 kfree(gss_msg); 525 err: 526 return ERR_PTR(err); 527 } 528 529 static struct gss_upcall_msg * 530 gss_setup_upcall(struct gss_auth *gss_auth, struct rpc_cred *cred) 531 { 532 struct gss_cred *gss_cred = container_of(cred, 533 struct gss_cred, gc_base); 534 struct gss_upcall_msg *gss_new, *gss_msg; 535 kuid_t uid = cred->cr_uid; 536 537 gss_new = gss_alloc_msg(gss_auth, uid, gss_cred->gc_principal); 538 if (IS_ERR(gss_new)) 539 return gss_new; 540 gss_msg = gss_add_msg(gss_new); 541 if (gss_msg == gss_new) { 542 int res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg); 543 if (res) { 544 gss_unhash_msg(gss_new); 545 gss_msg = ERR_PTR(res); 546 } 547 } else 548 gss_release_msg(gss_new); 549 return gss_msg; 550 } 551 552 static void warn_gssd(void) 553 { 554 dprintk("AUTH_GSS upcall failed. Please check user daemon is running.\n"); 555 } 556 557 static inline int 558 gss_refresh_upcall(struct rpc_task *task) 559 { 560 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 561 struct gss_auth *gss_auth = container_of(cred->cr_auth, 562 struct gss_auth, rpc_auth); 563 struct gss_cred *gss_cred = container_of(cred, 564 struct gss_cred, gc_base); 565 struct gss_upcall_msg *gss_msg; 566 struct rpc_pipe *pipe; 567 int err = 0; 568 569 dprintk("RPC: %5u %s for uid %u\n", 570 task->tk_pid, __func__, from_kuid(&init_user_ns, cred->cr_uid)); 571 gss_msg = gss_setup_upcall(gss_auth, cred); 572 if (PTR_ERR(gss_msg) == -EAGAIN) { 573 /* XXX: warning on the first, under the assumption we 574 * shouldn't normally hit this case on a refresh. */ 575 warn_gssd(); 576 task->tk_timeout = 15*HZ; 577 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 578 return -EAGAIN; 579 } 580 if (IS_ERR(gss_msg)) { 581 err = PTR_ERR(gss_msg); 582 goto out; 583 } 584 pipe = gss_msg->pipe; 585 spin_lock(&pipe->lock); 586 if (gss_cred->gc_upcall != NULL) 587 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 588 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { 589 task->tk_timeout = 0; 590 gss_cred->gc_upcall = gss_msg; 591 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 592 atomic_inc(&gss_msg->count); 593 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 594 } else { 595 gss_handle_downcall_result(gss_cred, gss_msg); 596 err = gss_msg->msg.errno; 597 } 598 spin_unlock(&pipe->lock); 599 gss_release_msg(gss_msg); 600 out: 601 dprintk("RPC: %5u %s for uid %u result %d\n", 602 task->tk_pid, __func__, 603 from_kuid(&init_user_ns, cred->cr_uid), err); 604 return err; 605 } 606 607 static inline int 608 gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 609 { 610 struct net *net = gss_auth->net; 611 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 612 struct rpc_pipe *pipe; 613 struct rpc_cred *cred = &gss_cred->gc_base; 614 struct gss_upcall_msg *gss_msg; 615 DEFINE_WAIT(wait); 616 int err; 617 618 dprintk("RPC: %s for uid %u\n", 619 __func__, from_kuid(&init_user_ns, cred->cr_uid)); 620 retry: 621 err = 0; 622 /* if gssd is down, just skip upcalling altogether */ 623 if (!gssd_running(net)) { 624 warn_gssd(); 625 return -EACCES; 626 } 627 gss_msg = gss_setup_upcall(gss_auth, cred); 628 if (PTR_ERR(gss_msg) == -EAGAIN) { 629 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 630 sn->pipe_version >= 0, 15 * HZ); 631 if (sn->pipe_version < 0) { 632 warn_gssd(); 633 err = -EACCES; 634 } 635 if (err < 0) 636 goto out; 637 goto retry; 638 } 639 if (IS_ERR(gss_msg)) { 640 err = PTR_ERR(gss_msg); 641 goto out; 642 } 643 pipe = gss_msg->pipe; 644 for (;;) { 645 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE); 646 spin_lock(&pipe->lock); 647 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 648 break; 649 } 650 spin_unlock(&pipe->lock); 651 if (fatal_signal_pending(current)) { 652 err = -ERESTARTSYS; 653 goto out_intr; 654 } 655 schedule(); 656 } 657 if (gss_msg->ctx) 658 gss_cred_set_ctx(cred, gss_msg->ctx); 659 else 660 err = gss_msg->msg.errno; 661 spin_unlock(&pipe->lock); 662 out_intr: 663 finish_wait(&gss_msg->waitqueue, &wait); 664 gss_release_msg(gss_msg); 665 out: 666 dprintk("RPC: %s for uid %u result %d\n", 667 __func__, from_kuid(&init_user_ns, cred->cr_uid), err); 668 return err; 669 } 670 671 #define MSG_BUF_MAXSIZE 1024 672 673 static ssize_t 674 gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 675 { 676 const void *p, *end; 677 void *buf; 678 struct gss_upcall_msg *gss_msg; 679 struct rpc_pipe *pipe = RPC_I(file_inode(filp))->pipe; 680 struct gss_cl_ctx *ctx; 681 uid_t id; 682 kuid_t uid; 683 ssize_t err = -EFBIG; 684 685 if (mlen > MSG_BUF_MAXSIZE) 686 goto out; 687 err = -ENOMEM; 688 buf = kmalloc(mlen, GFP_NOFS); 689 if (!buf) 690 goto out; 691 692 err = -EFAULT; 693 if (copy_from_user(buf, src, mlen)) 694 goto err; 695 696 end = (const void *)((char *)buf + mlen); 697 p = simple_get_bytes(buf, end, &id, sizeof(id)); 698 if (IS_ERR(p)) { 699 err = PTR_ERR(p); 700 goto err; 701 } 702 703 uid = make_kuid(&init_user_ns, id); 704 if (!uid_valid(uid)) { 705 err = -EINVAL; 706 goto err; 707 } 708 709 err = -ENOMEM; 710 ctx = gss_alloc_context(); 711 if (ctx == NULL) 712 goto err; 713 714 err = -ENOENT; 715 /* Find a matching upcall */ 716 spin_lock(&pipe->lock); 717 gss_msg = __gss_find_upcall(pipe, uid); 718 if (gss_msg == NULL) { 719 spin_unlock(&pipe->lock); 720 goto err_put_ctx; 721 } 722 list_del_init(&gss_msg->list); 723 spin_unlock(&pipe->lock); 724 725 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); 726 if (IS_ERR(p)) { 727 err = PTR_ERR(p); 728 switch (err) { 729 case -EACCES: 730 case -EKEYEXPIRED: 731 gss_msg->msg.errno = err; 732 err = mlen; 733 break; 734 case -EFAULT: 735 case -ENOMEM: 736 case -EINVAL: 737 case -ENOSYS: 738 gss_msg->msg.errno = -EAGAIN; 739 break; 740 default: 741 printk(KERN_CRIT "%s: bad return from " 742 "gss_fill_context: %zd\n", __func__, err); 743 BUG(); 744 } 745 goto err_release_msg; 746 } 747 gss_msg->ctx = gss_get_ctx(ctx); 748 err = mlen; 749 750 err_release_msg: 751 spin_lock(&pipe->lock); 752 __gss_unhash_msg(gss_msg); 753 spin_unlock(&pipe->lock); 754 gss_release_msg(gss_msg); 755 err_put_ctx: 756 gss_put_ctx(ctx); 757 err: 758 kfree(buf); 759 out: 760 dprintk("RPC: %s returning %Zd\n", __func__, err); 761 return err; 762 } 763 764 static int gss_pipe_open(struct inode *inode, int new_version) 765 { 766 struct net *net = inode->i_sb->s_fs_info; 767 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 768 int ret = 0; 769 770 spin_lock(&pipe_version_lock); 771 if (sn->pipe_version < 0) { 772 /* First open of any gss pipe determines the version: */ 773 sn->pipe_version = new_version; 774 rpc_wake_up(&pipe_version_rpc_waitqueue); 775 wake_up(&pipe_version_waitqueue); 776 } else if (sn->pipe_version != new_version) { 777 /* Trying to open a pipe of a different version */ 778 ret = -EBUSY; 779 goto out; 780 } 781 atomic_inc(&sn->pipe_users); 782 out: 783 spin_unlock(&pipe_version_lock); 784 return ret; 785 786 } 787 788 static int gss_pipe_open_v0(struct inode *inode) 789 { 790 return gss_pipe_open(inode, 0); 791 } 792 793 static int gss_pipe_open_v1(struct inode *inode) 794 { 795 return gss_pipe_open(inode, 1); 796 } 797 798 static void 799 gss_pipe_release(struct inode *inode) 800 { 801 struct net *net = inode->i_sb->s_fs_info; 802 struct rpc_pipe *pipe = RPC_I(inode)->pipe; 803 struct gss_upcall_msg *gss_msg; 804 805 restart: 806 spin_lock(&pipe->lock); 807 list_for_each_entry(gss_msg, &pipe->in_downcall, list) { 808 809 if (!list_empty(&gss_msg->msg.list)) 810 continue; 811 gss_msg->msg.errno = -EPIPE; 812 atomic_inc(&gss_msg->count); 813 __gss_unhash_msg(gss_msg); 814 spin_unlock(&pipe->lock); 815 gss_release_msg(gss_msg); 816 goto restart; 817 } 818 spin_unlock(&pipe->lock); 819 820 put_pipe_version(net); 821 } 822 823 static void 824 gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 825 { 826 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 827 828 if (msg->errno < 0) { 829 dprintk("RPC: %s releasing msg %p\n", 830 __func__, gss_msg); 831 atomic_inc(&gss_msg->count); 832 gss_unhash_msg(gss_msg); 833 if (msg->errno == -ETIMEDOUT) 834 warn_gssd(); 835 gss_release_msg(gss_msg); 836 } 837 } 838 839 static void gss_pipe_dentry_destroy(struct dentry *dir, 840 struct rpc_pipe_dir_object *pdo) 841 { 842 struct gss_pipe *gss_pipe = pdo->pdo_data; 843 struct rpc_pipe *pipe = gss_pipe->pipe; 844 845 if (pipe->dentry != NULL) { 846 rpc_unlink(pipe->dentry); 847 pipe->dentry = NULL; 848 } 849 } 850 851 static int gss_pipe_dentry_create(struct dentry *dir, 852 struct rpc_pipe_dir_object *pdo) 853 { 854 struct gss_pipe *p = pdo->pdo_data; 855 struct dentry *dentry; 856 857 dentry = rpc_mkpipe_dentry(dir, p->name, p->clnt, p->pipe); 858 if (IS_ERR(dentry)) 859 return PTR_ERR(dentry); 860 p->pipe->dentry = dentry; 861 return 0; 862 } 863 864 static const struct rpc_pipe_dir_object_ops gss_pipe_dir_object_ops = { 865 .create = gss_pipe_dentry_create, 866 .destroy = gss_pipe_dentry_destroy, 867 }; 868 869 static struct gss_pipe *gss_pipe_alloc(struct rpc_clnt *clnt, 870 const char *name, 871 const struct rpc_pipe_ops *upcall_ops) 872 { 873 struct gss_pipe *p; 874 int err = -ENOMEM; 875 876 p = kmalloc(sizeof(*p), GFP_KERNEL); 877 if (p == NULL) 878 goto err; 879 p->pipe = rpc_mkpipe_data(upcall_ops, RPC_PIPE_WAIT_FOR_OPEN); 880 if (IS_ERR(p->pipe)) { 881 err = PTR_ERR(p->pipe); 882 goto err_free_gss_pipe; 883 } 884 p->name = name; 885 p->clnt = clnt; 886 kref_init(&p->kref); 887 rpc_init_pipe_dir_object(&p->pdo, 888 &gss_pipe_dir_object_ops, 889 p); 890 return p; 891 err_free_gss_pipe: 892 kfree(p); 893 err: 894 return ERR_PTR(err); 895 } 896 897 struct gss_alloc_pdo { 898 struct rpc_clnt *clnt; 899 const char *name; 900 const struct rpc_pipe_ops *upcall_ops; 901 }; 902 903 static int gss_pipe_match_pdo(struct rpc_pipe_dir_object *pdo, void *data) 904 { 905 struct gss_pipe *gss_pipe; 906 struct gss_alloc_pdo *args = data; 907 908 if (pdo->pdo_ops != &gss_pipe_dir_object_ops) 909 return 0; 910 gss_pipe = container_of(pdo, struct gss_pipe, pdo); 911 if (strcmp(gss_pipe->name, args->name) != 0) 912 return 0; 913 if (!kref_get_unless_zero(&gss_pipe->kref)) 914 return 0; 915 return 1; 916 } 917 918 static struct rpc_pipe_dir_object *gss_pipe_alloc_pdo(void *data) 919 { 920 struct gss_pipe *gss_pipe; 921 struct gss_alloc_pdo *args = data; 922 923 gss_pipe = gss_pipe_alloc(args->clnt, args->name, args->upcall_ops); 924 if (!IS_ERR(gss_pipe)) 925 return &gss_pipe->pdo; 926 return NULL; 927 } 928 929 static struct gss_pipe *gss_pipe_get(struct rpc_clnt *clnt, 930 const char *name, 931 const struct rpc_pipe_ops *upcall_ops) 932 { 933 struct net *net = rpc_net_ns(clnt); 934 struct rpc_pipe_dir_object *pdo; 935 struct gss_alloc_pdo args = { 936 .clnt = clnt, 937 .name = name, 938 .upcall_ops = upcall_ops, 939 }; 940 941 pdo = rpc_find_or_alloc_pipe_dir_object(net, 942 &clnt->cl_pipedir_objects, 943 gss_pipe_match_pdo, 944 gss_pipe_alloc_pdo, 945 &args); 946 if (pdo != NULL) 947 return container_of(pdo, struct gss_pipe, pdo); 948 return ERR_PTR(-ENOMEM); 949 } 950 951 static void __gss_pipe_free(struct gss_pipe *p) 952 { 953 struct rpc_clnt *clnt = p->clnt; 954 struct net *net = rpc_net_ns(clnt); 955 956 rpc_remove_pipe_dir_object(net, 957 &clnt->cl_pipedir_objects, 958 &p->pdo); 959 rpc_destroy_pipe_data(p->pipe); 960 kfree(p); 961 } 962 963 static void __gss_pipe_release(struct kref *kref) 964 { 965 struct gss_pipe *p = container_of(kref, struct gss_pipe, kref); 966 967 __gss_pipe_free(p); 968 } 969 970 static void gss_pipe_free(struct gss_pipe *p) 971 { 972 if (p != NULL) 973 kref_put(&p->kref, __gss_pipe_release); 974 } 975 976 /* 977 * NOTE: we have the opportunity to use different 978 * parameters based on the input flavor (which must be a pseudoflavor) 979 */ 980 static struct gss_auth * 981 gss_create_new(struct rpc_auth_create_args *args, struct rpc_clnt *clnt) 982 { 983 rpc_authflavor_t flavor = args->pseudoflavor; 984 struct gss_auth *gss_auth; 985 struct gss_pipe *gss_pipe; 986 struct rpc_auth * auth; 987 int err = -ENOMEM; /* XXX? */ 988 989 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 990 991 if (!try_module_get(THIS_MODULE)) 992 return ERR_PTR(err); 993 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 994 goto out_dec; 995 INIT_HLIST_NODE(&gss_auth->hash); 996 gss_auth->target_name = NULL; 997 if (args->target_name) { 998 gss_auth->target_name = kstrdup(args->target_name, GFP_KERNEL); 999 if (gss_auth->target_name == NULL) 1000 goto err_free; 1001 } 1002 gss_auth->client = clnt; 1003 gss_auth->net = get_net(rpc_net_ns(clnt)); 1004 err = -EINVAL; 1005 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 1006 if (!gss_auth->mech) { 1007 dprintk("RPC: Pseudoflavor %d not found!\n", flavor); 1008 goto err_put_net; 1009 } 1010 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 1011 if (gss_auth->service == 0) 1012 goto err_put_mech; 1013 if (!gssd_running(gss_auth->net)) 1014 goto err_put_mech; 1015 auth = &gss_auth->rpc_auth; 1016 auth->au_cslack = GSS_CRED_SLACK >> 2; 1017 auth->au_rslack = GSS_VERF_SLACK >> 2; 1018 auth->au_ops = &authgss_ops; 1019 auth->au_flavor = flavor; 1020 atomic_set(&auth->au_count, 1); 1021 kref_init(&gss_auth->kref); 1022 1023 err = rpcauth_init_credcache(auth); 1024 if (err) 1025 goto err_put_mech; 1026 /* 1027 * Note: if we created the old pipe first, then someone who 1028 * examined the directory at the right moment might conclude 1029 * that we supported only the old pipe. So we instead create 1030 * the new pipe first. 1031 */ 1032 gss_pipe = gss_pipe_get(clnt, "gssd", &gss_upcall_ops_v1); 1033 if (IS_ERR(gss_pipe)) { 1034 err = PTR_ERR(gss_pipe); 1035 goto err_destroy_credcache; 1036 } 1037 gss_auth->gss_pipe[1] = gss_pipe; 1038 1039 gss_pipe = gss_pipe_get(clnt, gss_auth->mech->gm_name, 1040 &gss_upcall_ops_v0); 1041 if (IS_ERR(gss_pipe)) { 1042 err = PTR_ERR(gss_pipe); 1043 goto err_destroy_pipe_1; 1044 } 1045 gss_auth->gss_pipe[0] = gss_pipe; 1046 1047 return gss_auth; 1048 err_destroy_pipe_1: 1049 gss_pipe_free(gss_auth->gss_pipe[1]); 1050 err_destroy_credcache: 1051 rpcauth_destroy_credcache(auth); 1052 err_put_mech: 1053 gss_mech_put(gss_auth->mech); 1054 err_put_net: 1055 put_net(gss_auth->net); 1056 err_free: 1057 kfree(gss_auth->target_name); 1058 kfree(gss_auth); 1059 out_dec: 1060 module_put(THIS_MODULE); 1061 return ERR_PTR(err); 1062 } 1063 1064 static void 1065 gss_free(struct gss_auth *gss_auth) 1066 { 1067 gss_pipe_free(gss_auth->gss_pipe[0]); 1068 gss_pipe_free(gss_auth->gss_pipe[1]); 1069 gss_mech_put(gss_auth->mech); 1070 put_net(gss_auth->net); 1071 kfree(gss_auth->target_name); 1072 1073 kfree(gss_auth); 1074 module_put(THIS_MODULE); 1075 } 1076 1077 static void 1078 gss_free_callback(struct kref *kref) 1079 { 1080 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 1081 1082 gss_free(gss_auth); 1083 } 1084 1085 static void 1086 gss_put_auth(struct gss_auth *gss_auth) 1087 { 1088 kref_put(&gss_auth->kref, gss_free_callback); 1089 } 1090 1091 static void 1092 gss_destroy(struct rpc_auth *auth) 1093 { 1094 struct gss_auth *gss_auth = container_of(auth, 1095 struct gss_auth, rpc_auth); 1096 1097 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 1098 auth, auth->au_flavor); 1099 1100 if (hash_hashed(&gss_auth->hash)) { 1101 spin_lock(&gss_auth_hash_lock); 1102 hash_del(&gss_auth->hash); 1103 spin_unlock(&gss_auth_hash_lock); 1104 } 1105 1106 gss_pipe_free(gss_auth->gss_pipe[0]); 1107 gss_auth->gss_pipe[0] = NULL; 1108 gss_pipe_free(gss_auth->gss_pipe[1]); 1109 gss_auth->gss_pipe[1] = NULL; 1110 rpcauth_destroy_credcache(auth); 1111 1112 gss_put_auth(gss_auth); 1113 } 1114 1115 /* 1116 * Auths may be shared between rpc clients that were cloned from a 1117 * common client with the same xprt, if they also share the flavor and 1118 * target_name. 1119 * 1120 * The auth is looked up from the oldest parent sharing the same 1121 * cl_xprt, and the auth itself references only that common parent 1122 * (which is guaranteed to last as long as any of its descendants). 1123 */ 1124 static struct gss_auth * 1125 gss_auth_find_or_add_hashed(struct rpc_auth_create_args *args, 1126 struct rpc_clnt *clnt, 1127 struct gss_auth *new) 1128 { 1129 struct gss_auth *gss_auth; 1130 unsigned long hashval = (unsigned long)clnt; 1131 1132 spin_lock(&gss_auth_hash_lock); 1133 hash_for_each_possible(gss_auth_hash_table, 1134 gss_auth, 1135 hash, 1136 hashval) { 1137 if (gss_auth->client != clnt) 1138 continue; 1139 if (gss_auth->rpc_auth.au_flavor != args->pseudoflavor) 1140 continue; 1141 if (gss_auth->target_name != args->target_name) { 1142 if (gss_auth->target_name == NULL) 1143 continue; 1144 if (args->target_name == NULL) 1145 continue; 1146 if (strcmp(gss_auth->target_name, args->target_name)) 1147 continue; 1148 } 1149 if (!atomic_inc_not_zero(&gss_auth->rpc_auth.au_count)) 1150 continue; 1151 goto out; 1152 } 1153 if (new) 1154 hash_add(gss_auth_hash_table, &new->hash, hashval); 1155 gss_auth = new; 1156 out: 1157 spin_unlock(&gss_auth_hash_lock); 1158 return gss_auth; 1159 } 1160 1161 static struct gss_auth * 1162 gss_create_hashed(struct rpc_auth_create_args *args, struct rpc_clnt *clnt) 1163 { 1164 struct gss_auth *gss_auth; 1165 struct gss_auth *new; 1166 1167 gss_auth = gss_auth_find_or_add_hashed(args, clnt, NULL); 1168 if (gss_auth != NULL) 1169 goto out; 1170 new = gss_create_new(args, clnt); 1171 if (IS_ERR(new)) 1172 return new; 1173 gss_auth = gss_auth_find_or_add_hashed(args, clnt, new); 1174 if (gss_auth != new) 1175 gss_destroy(&new->rpc_auth); 1176 out: 1177 return gss_auth; 1178 } 1179 1180 static struct rpc_auth * 1181 gss_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt) 1182 { 1183 struct gss_auth *gss_auth; 1184 struct rpc_xprt *xprt = rcu_access_pointer(clnt->cl_xprt); 1185 1186 while (clnt != clnt->cl_parent) { 1187 struct rpc_clnt *parent = clnt->cl_parent; 1188 /* Find the original parent for this transport */ 1189 if (rcu_access_pointer(parent->cl_xprt) != xprt) 1190 break; 1191 clnt = parent; 1192 } 1193 1194 gss_auth = gss_create_hashed(args, clnt); 1195 if (IS_ERR(gss_auth)) 1196 return ERR_CAST(gss_auth); 1197 return &gss_auth->rpc_auth; 1198 } 1199 1200 /* 1201 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 1202 * to the server with the GSS control procedure field set to 1203 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 1204 * all RPCSEC_GSS state associated with that context. 1205 */ 1206 static int 1207 gss_destroying_context(struct rpc_cred *cred) 1208 { 1209 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 1210 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 1211 struct gss_cl_ctx *ctx = rcu_dereference_protected(gss_cred->gc_ctx, 1); 1212 struct rpc_task *task; 1213 1214 if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 1215 return 0; 1216 1217 ctx->gc_proc = RPC_GSS_PROC_DESTROY; 1218 cred->cr_ops = &gss_nullops; 1219 1220 /* Take a reference to ensure the cred will be destroyed either 1221 * by the RPC call or by the put_rpccred() below */ 1222 get_rpccred(cred); 1223 1224 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 1225 if (!IS_ERR(task)) 1226 rpc_put_task(task); 1227 1228 put_rpccred(cred); 1229 return 1; 1230 } 1231 1232 /* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 1233 * to create a new cred or context, so they check that things have been 1234 * allocated before freeing them. */ 1235 static void 1236 gss_do_free_ctx(struct gss_cl_ctx *ctx) 1237 { 1238 dprintk("RPC: %s\n", __func__); 1239 1240 gss_delete_sec_context(&ctx->gc_gss_ctx); 1241 kfree(ctx->gc_wire_ctx.data); 1242 kfree(ctx->gc_acceptor.data); 1243 kfree(ctx); 1244 } 1245 1246 static void 1247 gss_free_ctx_callback(struct rcu_head *head) 1248 { 1249 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 1250 gss_do_free_ctx(ctx); 1251 } 1252 1253 static void 1254 gss_free_ctx(struct gss_cl_ctx *ctx) 1255 { 1256 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 1257 } 1258 1259 static void 1260 gss_free_cred(struct gss_cred *gss_cred) 1261 { 1262 dprintk("RPC: %s cred=%p\n", __func__, gss_cred); 1263 kfree(gss_cred); 1264 } 1265 1266 static void 1267 gss_free_cred_callback(struct rcu_head *head) 1268 { 1269 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 1270 gss_free_cred(gss_cred); 1271 } 1272 1273 static void 1274 gss_destroy_nullcred(struct rpc_cred *cred) 1275 { 1276 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 1277 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 1278 struct gss_cl_ctx *ctx = rcu_dereference_protected(gss_cred->gc_ctx, 1); 1279 1280 RCU_INIT_POINTER(gss_cred->gc_ctx, NULL); 1281 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 1282 if (ctx) 1283 gss_put_ctx(ctx); 1284 gss_put_auth(gss_auth); 1285 } 1286 1287 static void 1288 gss_destroy_cred(struct rpc_cred *cred) 1289 { 1290 1291 if (gss_destroying_context(cred)) 1292 return; 1293 gss_destroy_nullcred(cred); 1294 } 1295 1296 /* 1297 * Lookup RPCSEC_GSS cred for the current process 1298 */ 1299 static struct rpc_cred * 1300 gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1301 { 1302 return rpcauth_lookup_credcache(auth, acred, flags); 1303 } 1304 1305 static struct rpc_cred * 1306 gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1307 { 1308 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1309 struct gss_cred *cred = NULL; 1310 int err = -ENOMEM; 1311 1312 dprintk("RPC: %s for uid %d, flavor %d\n", 1313 __func__, from_kuid(&init_user_ns, acred->uid), 1314 auth->au_flavor); 1315 1316 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 1317 goto out_err; 1318 1319 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 1320 /* 1321 * Note: in order to force a call to call_refresh(), we deliberately 1322 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 1323 */ 1324 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 1325 cred->gc_service = gss_auth->service; 1326 cred->gc_principal = NULL; 1327 if (acred->machine_cred) 1328 cred->gc_principal = acred->principal; 1329 kref_get(&gss_auth->kref); 1330 return &cred->gc_base; 1331 1332 out_err: 1333 dprintk("RPC: %s failed with error %d\n", __func__, err); 1334 return ERR_PTR(err); 1335 } 1336 1337 static int 1338 gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1339 { 1340 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1341 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1342 int err; 1343 1344 do { 1345 err = gss_create_upcall(gss_auth, gss_cred); 1346 } while (err == -EAGAIN); 1347 return err; 1348 } 1349 1350 static char * 1351 gss_stringify_acceptor(struct rpc_cred *cred) 1352 { 1353 char *string = NULL; 1354 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 1355 struct gss_cl_ctx *ctx; 1356 unsigned int len; 1357 struct xdr_netobj *acceptor; 1358 1359 rcu_read_lock(); 1360 ctx = rcu_dereference(gss_cred->gc_ctx); 1361 if (!ctx) 1362 goto out; 1363 1364 len = ctx->gc_acceptor.len; 1365 rcu_read_unlock(); 1366 1367 /* no point if there's no string */ 1368 if (!len) 1369 return NULL; 1370 realloc: 1371 string = kmalloc(len + 1, GFP_KERNEL); 1372 if (!string) 1373 return NULL; 1374 1375 rcu_read_lock(); 1376 ctx = rcu_dereference(gss_cred->gc_ctx); 1377 1378 /* did the ctx disappear or was it replaced by one with no acceptor? */ 1379 if (!ctx || !ctx->gc_acceptor.len) { 1380 kfree(string); 1381 string = NULL; 1382 goto out; 1383 } 1384 1385 acceptor = &ctx->gc_acceptor; 1386 1387 /* 1388 * Did we find a new acceptor that's longer than the original? Allocate 1389 * a longer buffer and try again. 1390 */ 1391 if (len < acceptor->len) { 1392 len = acceptor->len; 1393 rcu_read_unlock(); 1394 kfree(string); 1395 goto realloc; 1396 } 1397 1398 memcpy(string, acceptor->data, acceptor->len); 1399 string[acceptor->len] = '\0'; 1400 out: 1401 rcu_read_unlock(); 1402 return string; 1403 } 1404 1405 /* 1406 * Returns -EACCES if GSS context is NULL or will expire within the 1407 * timeout (miliseconds) 1408 */ 1409 static int 1410 gss_key_timeout(struct rpc_cred *rc) 1411 { 1412 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1413 struct gss_cl_ctx *ctx; 1414 unsigned long timeout = jiffies + (gss_key_expire_timeo * HZ); 1415 int ret = 0; 1416 1417 rcu_read_lock(); 1418 ctx = rcu_dereference(gss_cred->gc_ctx); 1419 if (!ctx || time_after(timeout, ctx->gc_expiry)) 1420 ret = -EACCES; 1421 rcu_read_unlock(); 1422 1423 return ret; 1424 } 1425 1426 static int 1427 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1428 { 1429 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1430 struct gss_cl_ctx *ctx; 1431 int ret; 1432 1433 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1434 goto out; 1435 /* Don't match with creds that have expired. */ 1436 rcu_read_lock(); 1437 ctx = rcu_dereference(gss_cred->gc_ctx); 1438 if (!ctx || time_after(jiffies, ctx->gc_expiry)) { 1439 rcu_read_unlock(); 1440 return 0; 1441 } 1442 rcu_read_unlock(); 1443 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1444 return 0; 1445 out: 1446 if (acred->principal != NULL) { 1447 if (gss_cred->gc_principal == NULL) 1448 return 0; 1449 ret = strcmp(acred->principal, gss_cred->gc_principal) == 0; 1450 goto check_expire; 1451 } 1452 if (gss_cred->gc_principal != NULL) 1453 return 0; 1454 ret = uid_eq(rc->cr_uid, acred->uid); 1455 1456 check_expire: 1457 if (ret == 0) 1458 return ret; 1459 1460 /* Notify acred users of GSS context expiration timeout */ 1461 if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags) && 1462 (gss_key_timeout(rc) != 0)) { 1463 /* test will now be done from generic cred */ 1464 test_and_clear_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags); 1465 /* tell NFS layer that key will expire soon */ 1466 set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags); 1467 } 1468 return ret; 1469 } 1470 1471 /* 1472 * Marshal credentials. 1473 * Maybe we should keep a cached credential for performance reasons. 1474 */ 1475 static __be32 * 1476 gss_marshal(struct rpc_task *task, __be32 *p) 1477 { 1478 struct rpc_rqst *req = task->tk_rqstp; 1479 struct rpc_cred *cred = req->rq_cred; 1480 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1481 gc_base); 1482 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1483 __be32 *cred_len; 1484 u32 maj_stat = 0; 1485 struct xdr_netobj mic; 1486 struct kvec iov; 1487 struct xdr_buf verf_buf; 1488 1489 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1490 1491 *p++ = htonl(RPC_AUTH_GSS); 1492 cred_len = p++; 1493 1494 spin_lock(&ctx->gc_seq_lock); 1495 req->rq_seqno = ctx->gc_seq++; 1496 spin_unlock(&ctx->gc_seq_lock); 1497 1498 *p++ = htonl((u32) RPC_GSS_VERSION); 1499 *p++ = htonl((u32) ctx->gc_proc); 1500 *p++ = htonl((u32) req->rq_seqno); 1501 *p++ = htonl((u32) gss_cred->gc_service); 1502 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1503 *cred_len = htonl((p - (cred_len + 1)) << 2); 1504 1505 /* We compute the checksum for the verifier over the xdr-encoded bytes 1506 * starting with the xid and ending at the end of the credential: */ 1507 iov.iov_base = xprt_skip_transport_header(req->rq_xprt, 1508 req->rq_snd_buf.head[0].iov_base); 1509 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1510 xdr_buf_from_iov(&iov, &verf_buf); 1511 1512 /* set verifier flavor*/ 1513 *p++ = htonl(RPC_AUTH_GSS); 1514 1515 mic.data = (u8 *)(p + 1); 1516 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1517 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1518 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1519 } else if (maj_stat != 0) { 1520 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1521 goto out_put_ctx; 1522 } 1523 p = xdr_encode_opaque(p, NULL, mic.len); 1524 gss_put_ctx(ctx); 1525 return p; 1526 out_put_ctx: 1527 gss_put_ctx(ctx); 1528 return NULL; 1529 } 1530 1531 static int gss_renew_cred(struct rpc_task *task) 1532 { 1533 struct rpc_cred *oldcred = task->tk_rqstp->rq_cred; 1534 struct gss_cred *gss_cred = container_of(oldcred, 1535 struct gss_cred, 1536 gc_base); 1537 struct rpc_auth *auth = oldcred->cr_auth; 1538 struct auth_cred acred = { 1539 .uid = oldcred->cr_uid, 1540 .principal = gss_cred->gc_principal, 1541 .machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0), 1542 }; 1543 struct rpc_cred *new; 1544 1545 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1546 if (IS_ERR(new)) 1547 return PTR_ERR(new); 1548 task->tk_rqstp->rq_cred = new; 1549 put_rpccred(oldcred); 1550 return 0; 1551 } 1552 1553 static int gss_cred_is_negative_entry(struct rpc_cred *cred) 1554 { 1555 if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) { 1556 unsigned long now = jiffies; 1557 unsigned long begin, expire; 1558 struct gss_cred *gss_cred; 1559 1560 gss_cred = container_of(cred, struct gss_cred, gc_base); 1561 begin = gss_cred->gc_upcall_timestamp; 1562 expire = begin + gss_expired_cred_retry_delay * HZ; 1563 1564 if (time_in_range_open(now, begin, expire)) 1565 return 1; 1566 } 1567 return 0; 1568 } 1569 1570 /* 1571 * Refresh credentials. XXX - finish 1572 */ 1573 static int 1574 gss_refresh(struct rpc_task *task) 1575 { 1576 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1577 int ret = 0; 1578 1579 if (gss_cred_is_negative_entry(cred)) 1580 return -EKEYEXPIRED; 1581 1582 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1583 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1584 ret = gss_renew_cred(task); 1585 if (ret < 0) 1586 goto out; 1587 cred = task->tk_rqstp->rq_cred; 1588 } 1589 1590 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1591 ret = gss_refresh_upcall(task); 1592 out: 1593 return ret; 1594 } 1595 1596 /* Dummy refresh routine: used only when destroying the context */ 1597 static int 1598 gss_refresh_null(struct rpc_task *task) 1599 { 1600 return 0; 1601 } 1602 1603 static __be32 * 1604 gss_validate(struct rpc_task *task, __be32 *p) 1605 { 1606 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1607 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1608 __be32 seq; 1609 struct kvec iov; 1610 struct xdr_buf verf_buf; 1611 struct xdr_netobj mic; 1612 u32 flav,len; 1613 u32 maj_stat; 1614 __be32 *ret = ERR_PTR(-EIO); 1615 1616 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1617 1618 flav = ntohl(*p++); 1619 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1620 goto out_bad; 1621 if (flav != RPC_AUTH_GSS) 1622 goto out_bad; 1623 seq = htonl(task->tk_rqstp->rq_seqno); 1624 iov.iov_base = &seq; 1625 iov.iov_len = sizeof(seq); 1626 xdr_buf_from_iov(&iov, &verf_buf); 1627 mic.data = (u8 *)p; 1628 mic.len = len; 1629 1630 ret = ERR_PTR(-EACCES); 1631 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1632 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1633 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1634 if (maj_stat) { 1635 dprintk("RPC: %5u %s: gss_verify_mic returned error 0x%08x\n", 1636 task->tk_pid, __func__, maj_stat); 1637 goto out_bad; 1638 } 1639 /* We leave it to unwrap to calculate au_rslack. For now we just 1640 * calculate the length of the verifier: */ 1641 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1642 gss_put_ctx(ctx); 1643 dprintk("RPC: %5u %s: gss_verify_mic succeeded.\n", 1644 task->tk_pid, __func__); 1645 return p + XDR_QUADLEN(len); 1646 out_bad: 1647 gss_put_ctx(ctx); 1648 dprintk("RPC: %5u %s failed ret %ld.\n", task->tk_pid, __func__, 1649 PTR_ERR(ret)); 1650 return ret; 1651 } 1652 1653 static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp, 1654 __be32 *p, void *obj) 1655 { 1656 struct xdr_stream xdr; 1657 1658 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, p); 1659 encode(rqstp, &xdr, obj); 1660 } 1661 1662 static inline int 1663 gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1664 kxdreproc_t encode, struct rpc_rqst *rqstp, 1665 __be32 *p, void *obj) 1666 { 1667 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1668 struct xdr_buf integ_buf; 1669 __be32 *integ_len = NULL; 1670 struct xdr_netobj mic; 1671 u32 offset; 1672 __be32 *q; 1673 struct kvec *iov; 1674 u32 maj_stat = 0; 1675 int status = -EIO; 1676 1677 integ_len = p++; 1678 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1679 *p++ = htonl(rqstp->rq_seqno); 1680 1681 gss_wrap_req_encode(encode, rqstp, p, obj); 1682 1683 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1684 offset, snd_buf->len - offset)) 1685 return status; 1686 *integ_len = htonl(integ_buf.len); 1687 1688 /* guess whether we're in the head or the tail: */ 1689 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1690 iov = snd_buf->tail; 1691 else 1692 iov = snd_buf->head; 1693 p = iov->iov_base + iov->iov_len; 1694 mic.data = (u8 *)(p + 1); 1695 1696 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1697 status = -EIO; /* XXX? */ 1698 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1699 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1700 else if (maj_stat) 1701 return status; 1702 q = xdr_encode_opaque(p, NULL, mic.len); 1703 1704 offset = (u8 *)q - (u8 *)p; 1705 iov->iov_len += offset; 1706 snd_buf->len += offset; 1707 return 0; 1708 } 1709 1710 static void 1711 priv_release_snd_buf(struct rpc_rqst *rqstp) 1712 { 1713 int i; 1714 1715 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1716 __free_page(rqstp->rq_enc_pages[i]); 1717 kfree(rqstp->rq_enc_pages); 1718 } 1719 1720 static int 1721 alloc_enc_pages(struct rpc_rqst *rqstp) 1722 { 1723 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1724 int first, last, i; 1725 1726 if (snd_buf->page_len == 0) { 1727 rqstp->rq_enc_pages_num = 0; 1728 return 0; 1729 } 1730 1731 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1732 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1733 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1734 rqstp->rq_enc_pages 1735 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1736 GFP_NOFS); 1737 if (!rqstp->rq_enc_pages) 1738 goto out; 1739 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1740 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1741 if (rqstp->rq_enc_pages[i] == NULL) 1742 goto out_free; 1743 } 1744 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1745 return 0; 1746 out_free: 1747 rqstp->rq_enc_pages_num = i; 1748 priv_release_snd_buf(rqstp); 1749 out: 1750 return -EAGAIN; 1751 } 1752 1753 static inline int 1754 gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1755 kxdreproc_t encode, struct rpc_rqst *rqstp, 1756 __be32 *p, void *obj) 1757 { 1758 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1759 u32 offset; 1760 u32 maj_stat; 1761 int status; 1762 __be32 *opaque_len; 1763 struct page **inpages; 1764 int first; 1765 int pad; 1766 struct kvec *iov; 1767 char *tmp; 1768 1769 opaque_len = p++; 1770 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1771 *p++ = htonl(rqstp->rq_seqno); 1772 1773 gss_wrap_req_encode(encode, rqstp, p, obj); 1774 1775 status = alloc_enc_pages(rqstp); 1776 if (status) 1777 return status; 1778 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1779 inpages = snd_buf->pages + first; 1780 snd_buf->pages = rqstp->rq_enc_pages; 1781 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1782 /* 1783 * Give the tail its own page, in case we need extra space in the 1784 * head when wrapping: 1785 * 1786 * call_allocate() allocates twice the slack space required 1787 * by the authentication flavor to rq_callsize. 1788 * For GSS, slack is GSS_CRED_SLACK. 1789 */ 1790 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1791 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1792 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1793 snd_buf->tail[0].iov_base = tmp; 1794 } 1795 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1796 /* slack space should prevent this ever happening: */ 1797 BUG_ON(snd_buf->len > snd_buf->buflen); 1798 status = -EIO; 1799 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1800 * done anyway, so it's safe to put the request on the wire: */ 1801 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1802 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1803 else if (maj_stat) 1804 return status; 1805 1806 *opaque_len = htonl(snd_buf->len - offset); 1807 /* guess whether we're in the head or the tail: */ 1808 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1809 iov = snd_buf->tail; 1810 else 1811 iov = snd_buf->head; 1812 p = iov->iov_base + iov->iov_len; 1813 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1814 memset(p, 0, pad); 1815 iov->iov_len += pad; 1816 snd_buf->len += pad; 1817 1818 return 0; 1819 } 1820 1821 static int 1822 gss_wrap_req(struct rpc_task *task, 1823 kxdreproc_t encode, void *rqstp, __be32 *p, void *obj) 1824 { 1825 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1826 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1827 gc_base); 1828 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1829 int status = -EIO; 1830 1831 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1832 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1833 /* The spec seems a little ambiguous here, but I think that not 1834 * wrapping context destruction requests makes the most sense. 1835 */ 1836 gss_wrap_req_encode(encode, rqstp, p, obj); 1837 status = 0; 1838 goto out; 1839 } 1840 switch (gss_cred->gc_service) { 1841 case RPC_GSS_SVC_NONE: 1842 gss_wrap_req_encode(encode, rqstp, p, obj); 1843 status = 0; 1844 break; 1845 case RPC_GSS_SVC_INTEGRITY: 1846 status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj); 1847 break; 1848 case RPC_GSS_SVC_PRIVACY: 1849 status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj); 1850 break; 1851 } 1852 out: 1853 gss_put_ctx(ctx); 1854 dprintk("RPC: %5u %s returning %d\n", task->tk_pid, __func__, status); 1855 return status; 1856 } 1857 1858 static inline int 1859 gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1860 struct rpc_rqst *rqstp, __be32 **p) 1861 { 1862 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1863 struct xdr_buf integ_buf; 1864 struct xdr_netobj mic; 1865 u32 data_offset, mic_offset; 1866 u32 integ_len; 1867 u32 maj_stat; 1868 int status = -EIO; 1869 1870 integ_len = ntohl(*(*p)++); 1871 if (integ_len & 3) 1872 return status; 1873 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1874 mic_offset = integ_len + data_offset; 1875 if (mic_offset > rcv_buf->len) 1876 return status; 1877 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1878 return status; 1879 1880 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1881 mic_offset - data_offset)) 1882 return status; 1883 1884 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1885 return status; 1886 1887 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1888 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1889 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1890 if (maj_stat != GSS_S_COMPLETE) 1891 return status; 1892 return 0; 1893 } 1894 1895 static inline int 1896 gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1897 struct rpc_rqst *rqstp, __be32 **p) 1898 { 1899 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1900 u32 offset; 1901 u32 opaque_len; 1902 u32 maj_stat; 1903 int status = -EIO; 1904 1905 opaque_len = ntohl(*(*p)++); 1906 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1907 if (offset + opaque_len > rcv_buf->len) 1908 return status; 1909 /* remove padding: */ 1910 rcv_buf->len = offset + opaque_len; 1911 1912 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1913 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1914 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1915 if (maj_stat != GSS_S_COMPLETE) 1916 return status; 1917 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1918 return status; 1919 1920 return 0; 1921 } 1922 1923 static int 1924 gss_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp, 1925 __be32 *p, void *obj) 1926 { 1927 struct xdr_stream xdr; 1928 1929 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); 1930 return decode(rqstp, &xdr, obj); 1931 } 1932 1933 static int 1934 gss_unwrap_resp(struct rpc_task *task, 1935 kxdrdproc_t decode, void *rqstp, __be32 *p, void *obj) 1936 { 1937 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1938 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1939 gc_base); 1940 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1941 __be32 *savedp = p; 1942 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1943 int savedlen = head->iov_len; 1944 int status = -EIO; 1945 1946 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1947 goto out_decode; 1948 switch (gss_cred->gc_service) { 1949 case RPC_GSS_SVC_NONE: 1950 break; 1951 case RPC_GSS_SVC_INTEGRITY: 1952 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1953 if (status) 1954 goto out; 1955 break; 1956 case RPC_GSS_SVC_PRIVACY: 1957 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1958 if (status) 1959 goto out; 1960 break; 1961 } 1962 /* take into account extra slack for integrity and privacy cases: */ 1963 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1964 + (savedlen - head->iov_len); 1965 out_decode: 1966 status = gss_unwrap_req_decode(decode, rqstp, p, obj); 1967 out: 1968 gss_put_ctx(ctx); 1969 dprintk("RPC: %5u %s returning %d\n", 1970 task->tk_pid, __func__, status); 1971 return status; 1972 } 1973 1974 static const struct rpc_authops authgss_ops = { 1975 .owner = THIS_MODULE, 1976 .au_flavor = RPC_AUTH_GSS, 1977 .au_name = "RPCSEC_GSS", 1978 .create = gss_create, 1979 .destroy = gss_destroy, 1980 .lookup_cred = gss_lookup_cred, 1981 .crcreate = gss_create_cred, 1982 .list_pseudoflavors = gss_mech_list_pseudoflavors, 1983 .info2flavor = gss_mech_info2flavor, 1984 .flavor2info = gss_mech_flavor2info, 1985 }; 1986 1987 static const struct rpc_credops gss_credops = { 1988 .cr_name = "AUTH_GSS", 1989 .crdestroy = gss_destroy_cred, 1990 .cr_init = gss_cred_init, 1991 .crbind = rpcauth_generic_bind_cred, 1992 .crmatch = gss_match, 1993 .crmarshal = gss_marshal, 1994 .crrefresh = gss_refresh, 1995 .crvalidate = gss_validate, 1996 .crwrap_req = gss_wrap_req, 1997 .crunwrap_resp = gss_unwrap_resp, 1998 .crkey_timeout = gss_key_timeout, 1999 .crstringify_acceptor = gss_stringify_acceptor, 2000 }; 2001 2002 static const struct rpc_credops gss_nullops = { 2003 .cr_name = "AUTH_GSS", 2004 .crdestroy = gss_destroy_nullcred, 2005 .crbind = rpcauth_generic_bind_cred, 2006 .crmatch = gss_match, 2007 .crmarshal = gss_marshal, 2008 .crrefresh = gss_refresh_null, 2009 .crvalidate = gss_validate, 2010 .crwrap_req = gss_wrap_req, 2011 .crunwrap_resp = gss_unwrap_resp, 2012 .crstringify_acceptor = gss_stringify_acceptor, 2013 }; 2014 2015 static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 2016 .upcall = rpc_pipe_generic_upcall, 2017 .downcall = gss_pipe_downcall, 2018 .destroy_msg = gss_pipe_destroy_msg, 2019 .open_pipe = gss_pipe_open_v0, 2020 .release_pipe = gss_pipe_release, 2021 }; 2022 2023 static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 2024 .upcall = rpc_pipe_generic_upcall, 2025 .downcall = gss_pipe_downcall, 2026 .destroy_msg = gss_pipe_destroy_msg, 2027 .open_pipe = gss_pipe_open_v1, 2028 .release_pipe = gss_pipe_release, 2029 }; 2030 2031 static __net_init int rpcsec_gss_init_net(struct net *net) 2032 { 2033 return gss_svc_init_net(net); 2034 } 2035 2036 static __net_exit void rpcsec_gss_exit_net(struct net *net) 2037 { 2038 gss_svc_shutdown_net(net); 2039 } 2040 2041 static struct pernet_operations rpcsec_gss_net_ops = { 2042 .init = rpcsec_gss_init_net, 2043 .exit = rpcsec_gss_exit_net, 2044 }; 2045 2046 /* 2047 * Initialize RPCSEC_GSS module 2048 */ 2049 static int __init init_rpcsec_gss(void) 2050 { 2051 int err = 0; 2052 2053 err = rpcauth_register(&authgss_ops); 2054 if (err) 2055 goto out; 2056 err = gss_svc_init(); 2057 if (err) 2058 goto out_unregister; 2059 err = register_pernet_subsys(&rpcsec_gss_net_ops); 2060 if (err) 2061 goto out_svc_exit; 2062 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 2063 return 0; 2064 out_svc_exit: 2065 gss_svc_shutdown(); 2066 out_unregister: 2067 rpcauth_unregister(&authgss_ops); 2068 out: 2069 return err; 2070 } 2071 2072 static void __exit exit_rpcsec_gss(void) 2073 { 2074 unregister_pernet_subsys(&rpcsec_gss_net_ops); 2075 gss_svc_shutdown(); 2076 rpcauth_unregister(&authgss_ops); 2077 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 2078 } 2079 2080 MODULE_ALIAS("rpc-auth-6"); 2081 MODULE_LICENSE("GPL"); 2082 module_param_named(expired_cred_retry_delay, 2083 gss_expired_cred_retry_delay, 2084 uint, 0644); 2085 MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until " 2086 "the RPC engine retries an expired credential"); 2087 2088 module_param_named(key_expire_timeo, 2089 gss_key_expire_timeo, 2090 uint, 0644); 2091 MODULE_PARM_DESC(key_expire_timeo, "Time (in seconds) at the end of a " 2092 "credential keys lifetime where the NFS layer cleans up " 2093 "prior to key expiration"); 2094 2095 module_init(init_rpcsec_gss) 2096 module_exit(exit_rpcsec_gss) 2097