auth_gss.c revision 90602c7b192fdd3e6b7c7623479f4bc86ed7ee34
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 unsigned long now = jiffies; 196 u32 window_size; 197 int ret; 198 199 /* First unsigned int gives the remaining lifetime in seconds of the 200 * credential - e.g. the remaining TGT lifetime for Kerberos or 201 * the -t value passed to GSSD. 202 */ 203 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 204 if (IS_ERR(p)) 205 goto err; 206 if (timeout == 0) 207 timeout = GSSD_MIN_TIMEOUT; 208 ctx->gc_expiry = now + ((unsigned long)timeout * HZ); 209 /* Sequence number window. Determines the maximum number of 210 * simultaneous requests 211 */ 212 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 213 if (IS_ERR(p)) 214 goto err; 215 ctx->gc_win = window_size; 216 /* gssd signals an error by passing ctx->gc_win = 0: */ 217 if (ctx->gc_win == 0) { 218 /* 219 * in which case, p points to an error code. Anything other 220 * than -EKEYEXPIRED gets converted to -EACCES. 221 */ 222 p = simple_get_bytes(p, end, &ret, sizeof(ret)); 223 if (!IS_ERR(p)) 224 p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) : 225 ERR_PTR(-EACCES); 226 goto err; 227 } 228 /* copy the opaque wire context */ 229 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 230 if (IS_ERR(p)) 231 goto err; 232 /* import the opaque security context */ 233 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 234 if (IS_ERR(p)) 235 goto err; 236 q = (const void *)((const char *)p + seclen); 237 if (unlikely(q > end || q < p)) { 238 p = ERR_PTR(-EFAULT); 239 goto err; 240 } 241 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, GFP_NOFS); 242 if (ret < 0) { 243 p = ERR_PTR(ret); 244 goto err; 245 } 246 dprintk("RPC: %s Success. gc_expiry %lu now %lu timeout %u\n", 247 __func__, ctx->gc_expiry, now, timeout); 248 return q; 249err: 250 dprintk("RPC: %s returns %ld gc_expiry %lu now %lu timeout %u\n", 251 __func__, -PTR_ERR(p), ctx->gc_expiry, now, timeout); 252 return p; 253} 254 255#define UPCALL_BUF_LEN 128 256 257struct gss_upcall_msg { 258 atomic_t count; 259 kuid_t uid; 260 struct rpc_pipe_msg msg; 261 struct list_head list; 262 struct gss_auth *auth; 263 struct rpc_pipe *pipe; 264 struct rpc_wait_queue rpc_waitqueue; 265 wait_queue_head_t waitqueue; 266 struct gss_cl_ctx *ctx; 267 char databuf[UPCALL_BUF_LEN]; 268}; 269 270static int get_pipe_version(void) 271{ 272 int ret; 273 274 spin_lock(&pipe_version_lock); 275 if (pipe_version >= 0) { 276 atomic_inc(&pipe_users); 277 ret = pipe_version; 278 } else 279 ret = -EAGAIN; 280 spin_unlock(&pipe_version_lock); 281 return ret; 282} 283 284static void put_pipe_version(void) 285{ 286 if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) { 287 pipe_version = -1; 288 spin_unlock(&pipe_version_lock); 289 } 290} 291 292static void 293gss_release_msg(struct gss_upcall_msg *gss_msg) 294{ 295 if (!atomic_dec_and_test(&gss_msg->count)) 296 return; 297 put_pipe_version(); 298 BUG_ON(!list_empty(&gss_msg->list)); 299 if (gss_msg->ctx != NULL) 300 gss_put_ctx(gss_msg->ctx); 301 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue); 302 kfree(gss_msg); 303} 304 305static struct gss_upcall_msg * 306__gss_find_upcall(struct rpc_pipe *pipe, kuid_t uid) 307{ 308 struct gss_upcall_msg *pos; 309 list_for_each_entry(pos, &pipe->in_downcall, list) { 310 if (!uid_eq(pos->uid, uid)) 311 continue; 312 atomic_inc(&pos->count); 313 dprintk("RPC: %s found msg %p\n", __func__, pos); 314 return pos; 315 } 316 dprintk("RPC: %s found nothing\n", __func__); 317 return NULL; 318} 319 320/* Try to add an upcall to the pipefs queue. 321 * If an upcall owned by our uid already exists, then we return a reference 322 * to that upcall instead of adding the new upcall. 323 */ 324static inline struct gss_upcall_msg * 325gss_add_msg(struct gss_upcall_msg *gss_msg) 326{ 327 struct rpc_pipe *pipe = gss_msg->pipe; 328 struct gss_upcall_msg *old; 329 330 spin_lock(&pipe->lock); 331 old = __gss_find_upcall(pipe, gss_msg->uid); 332 if (old == NULL) { 333 atomic_inc(&gss_msg->count); 334 list_add(&gss_msg->list, &pipe->in_downcall); 335 } else 336 gss_msg = old; 337 spin_unlock(&pipe->lock); 338 return gss_msg; 339} 340 341static void 342__gss_unhash_msg(struct gss_upcall_msg *gss_msg) 343{ 344 list_del_init(&gss_msg->list); 345 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 346 wake_up_all(&gss_msg->waitqueue); 347 atomic_dec(&gss_msg->count); 348} 349 350static void 351gss_unhash_msg(struct gss_upcall_msg *gss_msg) 352{ 353 struct rpc_pipe *pipe = gss_msg->pipe; 354 355 if (list_empty(&gss_msg->list)) 356 return; 357 spin_lock(&pipe->lock); 358 if (!list_empty(&gss_msg->list)) 359 __gss_unhash_msg(gss_msg); 360 spin_unlock(&pipe->lock); 361} 362 363static void 364gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg) 365{ 366 switch (gss_msg->msg.errno) { 367 case 0: 368 if (gss_msg->ctx == NULL) 369 break; 370 clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 371 gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx); 372 break; 373 case -EKEYEXPIRED: 374 set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 375 } 376 gss_cred->gc_upcall_timestamp = jiffies; 377 gss_cred->gc_upcall = NULL; 378 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 379} 380 381static void 382gss_upcall_callback(struct rpc_task *task) 383{ 384 struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred, 385 struct gss_cred, gc_base); 386 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 387 struct rpc_pipe *pipe = gss_msg->pipe; 388 389 spin_lock(&pipe->lock); 390 gss_handle_downcall_result(gss_cred, gss_msg); 391 spin_unlock(&pipe->lock); 392 task->tk_status = gss_msg->msg.errno; 393 gss_release_msg(gss_msg); 394} 395 396static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 397{ 398 uid_t uid = from_kuid(&init_user_ns, gss_msg->uid); 399 memcpy(gss_msg->databuf, &uid, sizeof(uid)); 400 gss_msg->msg.data = gss_msg->databuf; 401 gss_msg->msg.len = sizeof(uid); 402 BUG_ON(sizeof(uid) > UPCALL_BUF_LEN); 403} 404 405static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 406 struct rpc_clnt *clnt, 407 const char *service_name) 408{ 409 struct gss_api_mech *mech = gss_msg->auth->mech; 410 char *p = gss_msg->databuf; 411 int len = 0; 412 413 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ", 414 mech->gm_name, 415 from_kuid(&init_user_ns, gss_msg->uid)); 416 p += gss_msg->msg.len; 417 if (clnt->cl_principal) { 418 len = sprintf(p, "target=%s ", clnt->cl_principal); 419 p += len; 420 gss_msg->msg.len += len; 421 } 422 if (service_name != NULL) { 423 len = sprintf(p, "service=%s ", service_name); 424 p += len; 425 gss_msg->msg.len += len; 426 } 427 if (mech->gm_upcall_enctypes) { 428 len = sprintf(p, "enctypes=%s ", mech->gm_upcall_enctypes); 429 p += len; 430 gss_msg->msg.len += len; 431 } 432 len = sprintf(p, "\n"); 433 gss_msg->msg.len += len; 434 435 gss_msg->msg.data = gss_msg->databuf; 436 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); 437} 438 439static void gss_encode_msg(struct gss_upcall_msg *gss_msg, 440 struct rpc_clnt *clnt, 441 const char *service_name) 442{ 443 if (pipe_version == 0) 444 gss_encode_v0_msg(gss_msg); 445 else /* pipe_version == 1 */ 446 gss_encode_v1_msg(gss_msg, clnt, service_name); 447} 448 449static struct gss_upcall_msg * 450gss_alloc_msg(struct gss_auth *gss_auth, struct rpc_clnt *clnt, 451 kuid_t uid, const char *service_name) 452{ 453 struct gss_upcall_msg *gss_msg; 454 int vers; 455 456 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 457 if (gss_msg == NULL) 458 return ERR_PTR(-ENOMEM); 459 vers = get_pipe_version(); 460 if (vers < 0) { 461 kfree(gss_msg); 462 return ERR_PTR(vers); 463 } 464 gss_msg->pipe = gss_auth->pipe[vers]; 465 INIT_LIST_HEAD(&gss_msg->list); 466 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 467 init_waitqueue_head(&gss_msg->waitqueue); 468 atomic_set(&gss_msg->count, 1); 469 gss_msg->uid = uid; 470 gss_msg->auth = gss_auth; 471 gss_encode_msg(gss_msg, clnt, service_name); 472 return gss_msg; 473} 474 475static struct gss_upcall_msg * 476gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 477{ 478 struct gss_cred *gss_cred = container_of(cred, 479 struct gss_cred, gc_base); 480 struct gss_upcall_msg *gss_new, *gss_msg; 481 kuid_t uid = cred->cr_uid; 482 483 gss_new = gss_alloc_msg(gss_auth, clnt, uid, gss_cred->gc_principal); 484 if (IS_ERR(gss_new)) 485 return gss_new; 486 gss_msg = gss_add_msg(gss_new); 487 if (gss_msg == gss_new) { 488 int res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg); 489 if (res) { 490 gss_unhash_msg(gss_new); 491 gss_msg = ERR_PTR(res); 492 } 493 } else 494 gss_release_msg(gss_new); 495 return gss_msg; 496} 497 498static void warn_gssd(void) 499{ 500 static unsigned long ratelimit; 501 unsigned long now = jiffies; 502 503 if (time_after(now, ratelimit)) { 504 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 505 "Please check user daemon is running.\n"); 506 ratelimit = now + 15*HZ; 507 } 508} 509 510static inline int 511gss_refresh_upcall(struct rpc_task *task) 512{ 513 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 514 struct gss_auth *gss_auth = container_of(cred->cr_auth, 515 struct gss_auth, rpc_auth); 516 struct gss_cred *gss_cred = container_of(cred, 517 struct gss_cred, gc_base); 518 struct gss_upcall_msg *gss_msg; 519 struct rpc_pipe *pipe; 520 int err = 0; 521 522 dprintk("RPC: %5u %s for uid %u\n", 523 task->tk_pid, __func__, from_kuid(&init_user_ns, cred->cr_uid)); 524 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 525 if (PTR_ERR(gss_msg) == -EAGAIN) { 526 /* XXX: warning on the first, under the assumption we 527 * shouldn't normally hit this case on a refresh. */ 528 warn_gssd(); 529 task->tk_timeout = 15*HZ; 530 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 531 return -EAGAIN; 532 } 533 if (IS_ERR(gss_msg)) { 534 err = PTR_ERR(gss_msg); 535 goto out; 536 } 537 pipe = gss_msg->pipe; 538 spin_lock(&pipe->lock); 539 if (gss_cred->gc_upcall != NULL) 540 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 541 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { 542 task->tk_timeout = 0; 543 gss_cred->gc_upcall = gss_msg; 544 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 545 atomic_inc(&gss_msg->count); 546 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 547 } else { 548 gss_handle_downcall_result(gss_cred, gss_msg); 549 err = gss_msg->msg.errno; 550 } 551 spin_unlock(&pipe->lock); 552 gss_release_msg(gss_msg); 553out: 554 dprintk("RPC: %5u %s for uid %u result %d\n", 555 task->tk_pid, __func__, 556 from_kuid(&init_user_ns, cred->cr_uid), err); 557 return err; 558} 559 560static inline int 561gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 562{ 563 struct rpc_pipe *pipe; 564 struct rpc_cred *cred = &gss_cred->gc_base; 565 struct gss_upcall_msg *gss_msg; 566 DEFINE_WAIT(wait); 567 int err = 0; 568 569 dprintk("RPC: %s for uid %u\n", 570 __func__, from_kuid(&init_user_ns, cred->cr_uid)); 571retry: 572 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 573 if (PTR_ERR(gss_msg) == -EAGAIN) { 574 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 575 pipe_version >= 0, 15*HZ); 576 if (pipe_version < 0) { 577 warn_gssd(); 578 err = -EACCES; 579 } 580 if (err) 581 goto out; 582 goto retry; 583 } 584 if (IS_ERR(gss_msg)) { 585 err = PTR_ERR(gss_msg); 586 goto out; 587 } 588 pipe = gss_msg->pipe; 589 for (;;) { 590 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE); 591 spin_lock(&pipe->lock); 592 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 593 break; 594 } 595 spin_unlock(&pipe->lock); 596 if (fatal_signal_pending(current)) { 597 err = -ERESTARTSYS; 598 goto out_intr; 599 } 600 schedule(); 601 } 602 if (gss_msg->ctx) 603 gss_cred_set_ctx(cred, gss_msg->ctx); 604 else 605 err = gss_msg->msg.errno; 606 spin_unlock(&pipe->lock); 607out_intr: 608 finish_wait(&gss_msg->waitqueue, &wait); 609 gss_release_msg(gss_msg); 610out: 611 dprintk("RPC: %s for uid %u result %d\n", 612 __func__, from_kuid(&init_user_ns, cred->cr_uid), err); 613 return err; 614} 615 616#define MSG_BUF_MAXSIZE 1024 617 618static ssize_t 619gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 620{ 621 const void *p, *end; 622 void *buf; 623 struct gss_upcall_msg *gss_msg; 624 struct rpc_pipe *pipe = RPC_I(filp->f_dentry->d_inode)->pipe; 625 struct gss_cl_ctx *ctx; 626 uid_t id; 627 kuid_t uid; 628 ssize_t err = -EFBIG; 629 630 if (mlen > MSG_BUF_MAXSIZE) 631 goto out; 632 err = -ENOMEM; 633 buf = kmalloc(mlen, GFP_NOFS); 634 if (!buf) 635 goto out; 636 637 err = -EFAULT; 638 if (copy_from_user(buf, src, mlen)) 639 goto err; 640 641 end = (const void *)((char *)buf + mlen); 642 p = simple_get_bytes(buf, end, &id, sizeof(id)); 643 if (IS_ERR(p)) { 644 err = PTR_ERR(p); 645 goto err; 646 } 647 648 uid = make_kuid(&init_user_ns, id); 649 if (!uid_valid(uid)) { 650 err = -EINVAL; 651 goto err; 652 } 653 654 err = -ENOMEM; 655 ctx = gss_alloc_context(); 656 if (ctx == NULL) 657 goto err; 658 659 err = -ENOENT; 660 /* Find a matching upcall */ 661 spin_lock(&pipe->lock); 662 gss_msg = __gss_find_upcall(pipe, uid); 663 if (gss_msg == NULL) { 664 spin_unlock(&pipe->lock); 665 goto err_put_ctx; 666 } 667 list_del_init(&gss_msg->list); 668 spin_unlock(&pipe->lock); 669 670 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); 671 if (IS_ERR(p)) { 672 err = PTR_ERR(p); 673 switch (err) { 674 case -EACCES: 675 case -EKEYEXPIRED: 676 gss_msg->msg.errno = err; 677 err = mlen; 678 break; 679 case -EFAULT: 680 case -ENOMEM: 681 case -EINVAL: 682 case -ENOSYS: 683 gss_msg->msg.errno = -EAGAIN; 684 break; 685 default: 686 printk(KERN_CRIT "%s: bad return from " 687 "gss_fill_context: %zd\n", __func__, err); 688 BUG(); 689 } 690 goto err_release_msg; 691 } 692 gss_msg->ctx = gss_get_ctx(ctx); 693 err = mlen; 694 695err_release_msg: 696 spin_lock(&pipe->lock); 697 __gss_unhash_msg(gss_msg); 698 spin_unlock(&pipe->lock); 699 gss_release_msg(gss_msg); 700err_put_ctx: 701 gss_put_ctx(ctx); 702err: 703 kfree(buf); 704out: 705 dprintk("RPC: %s returning %Zd\n", __func__, err); 706 return err; 707} 708 709static int gss_pipe_open(struct inode *inode, int new_version) 710{ 711 int ret = 0; 712 713 spin_lock(&pipe_version_lock); 714 if (pipe_version < 0) { 715 /* First open of any gss pipe determines the version: */ 716 pipe_version = new_version; 717 rpc_wake_up(&pipe_version_rpc_waitqueue); 718 wake_up(&pipe_version_waitqueue); 719 } else if (pipe_version != new_version) { 720 /* Trying to open a pipe of a different version */ 721 ret = -EBUSY; 722 goto out; 723 } 724 atomic_inc(&pipe_users); 725out: 726 spin_unlock(&pipe_version_lock); 727 return ret; 728 729} 730 731static int gss_pipe_open_v0(struct inode *inode) 732{ 733 return gss_pipe_open(inode, 0); 734} 735 736static int gss_pipe_open_v1(struct inode *inode) 737{ 738 return gss_pipe_open(inode, 1); 739} 740 741static void 742gss_pipe_release(struct inode *inode) 743{ 744 struct rpc_pipe *pipe = RPC_I(inode)->pipe; 745 struct gss_upcall_msg *gss_msg; 746 747restart: 748 spin_lock(&pipe->lock); 749 list_for_each_entry(gss_msg, &pipe->in_downcall, list) { 750 751 if (!list_empty(&gss_msg->msg.list)) 752 continue; 753 gss_msg->msg.errno = -EPIPE; 754 atomic_inc(&gss_msg->count); 755 __gss_unhash_msg(gss_msg); 756 spin_unlock(&pipe->lock); 757 gss_release_msg(gss_msg); 758 goto restart; 759 } 760 spin_unlock(&pipe->lock); 761 762 put_pipe_version(); 763} 764 765static void 766gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 767{ 768 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 769 770 if (msg->errno < 0) { 771 dprintk("RPC: %s releasing msg %p\n", 772 __func__, gss_msg); 773 atomic_inc(&gss_msg->count); 774 gss_unhash_msg(gss_msg); 775 if (msg->errno == -ETIMEDOUT) 776 warn_gssd(); 777 gss_release_msg(gss_msg); 778 } 779} 780 781static void gss_pipes_dentries_destroy(struct rpc_auth *auth) 782{ 783 struct gss_auth *gss_auth; 784 785 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 786 if (gss_auth->pipe[0]->dentry) 787 rpc_unlink(gss_auth->pipe[0]->dentry); 788 if (gss_auth->pipe[1]->dentry) 789 rpc_unlink(gss_auth->pipe[1]->dentry); 790} 791 792static int gss_pipes_dentries_create(struct rpc_auth *auth) 793{ 794 int err; 795 struct gss_auth *gss_auth; 796 struct rpc_clnt *clnt; 797 798 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 799 clnt = gss_auth->client; 800 801 gss_auth->pipe[1]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry, 802 "gssd", 803 clnt, gss_auth->pipe[1]); 804 if (IS_ERR(gss_auth->pipe[1]->dentry)) 805 return PTR_ERR(gss_auth->pipe[1]->dentry); 806 gss_auth->pipe[0]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry, 807 gss_auth->mech->gm_name, 808 clnt, gss_auth->pipe[0]); 809 if (IS_ERR(gss_auth->pipe[0]->dentry)) { 810 err = PTR_ERR(gss_auth->pipe[0]->dentry); 811 goto err_unlink_pipe_1; 812 } 813 return 0; 814 815err_unlink_pipe_1: 816 rpc_unlink(gss_auth->pipe[1]->dentry); 817 return err; 818} 819 820static void gss_pipes_dentries_destroy_net(struct rpc_clnt *clnt, 821 struct rpc_auth *auth) 822{ 823 struct net *net = rpc_net_ns(clnt); 824 struct super_block *sb; 825 826 sb = rpc_get_sb_net(net); 827 if (sb) { 828 if (clnt->cl_dentry) 829 gss_pipes_dentries_destroy(auth); 830 rpc_put_sb_net(net); 831 } 832} 833 834static int gss_pipes_dentries_create_net(struct rpc_clnt *clnt, 835 struct rpc_auth *auth) 836{ 837 struct net *net = rpc_net_ns(clnt); 838 struct super_block *sb; 839 int err = 0; 840 841 sb = rpc_get_sb_net(net); 842 if (sb) { 843 if (clnt->cl_dentry) 844 err = gss_pipes_dentries_create(auth); 845 rpc_put_sb_net(net); 846 } 847 return err; 848} 849 850/* 851 * NOTE: we have the opportunity to use different 852 * parameters based on the input flavor (which must be a pseudoflavor) 853 */ 854static struct rpc_auth * 855gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 856{ 857 struct gss_auth *gss_auth; 858 struct rpc_auth * auth; 859 int err = -ENOMEM; /* XXX? */ 860 861 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 862 863 if (!try_module_get(THIS_MODULE)) 864 return ERR_PTR(err); 865 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 866 goto out_dec; 867 gss_auth->client = clnt; 868 err = -EINVAL; 869 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 870 if (!gss_auth->mech) { 871 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 872 __func__, flavor); 873 goto err_free; 874 } 875 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 876 if (gss_auth->service == 0) 877 goto err_put_mech; 878 auth = &gss_auth->rpc_auth; 879 auth->au_cslack = GSS_CRED_SLACK >> 2; 880 auth->au_rslack = GSS_VERF_SLACK >> 2; 881 auth->au_ops = &authgss_ops; 882 auth->au_flavor = flavor; 883 atomic_set(&auth->au_count, 1); 884 kref_init(&gss_auth->kref); 885 886 /* 887 * Note: if we created the old pipe first, then someone who 888 * examined the directory at the right moment might conclude 889 * that we supported only the old pipe. So we instead create 890 * the new pipe first. 891 */ 892 gss_auth->pipe[1] = rpc_mkpipe_data(&gss_upcall_ops_v1, 893 RPC_PIPE_WAIT_FOR_OPEN); 894 if (IS_ERR(gss_auth->pipe[1])) { 895 err = PTR_ERR(gss_auth->pipe[1]); 896 goto err_put_mech; 897 } 898 899 gss_auth->pipe[0] = rpc_mkpipe_data(&gss_upcall_ops_v0, 900 RPC_PIPE_WAIT_FOR_OPEN); 901 if (IS_ERR(gss_auth->pipe[0])) { 902 err = PTR_ERR(gss_auth->pipe[0]); 903 goto err_destroy_pipe_1; 904 } 905 err = gss_pipes_dentries_create_net(clnt, auth); 906 if (err) 907 goto err_destroy_pipe_0; 908 err = rpcauth_init_credcache(auth); 909 if (err) 910 goto err_unlink_pipes; 911 912 return auth; 913err_unlink_pipes: 914 gss_pipes_dentries_destroy_net(clnt, auth); 915err_destroy_pipe_0: 916 rpc_destroy_pipe_data(gss_auth->pipe[0]); 917err_destroy_pipe_1: 918 rpc_destroy_pipe_data(gss_auth->pipe[1]); 919err_put_mech: 920 gss_mech_put(gss_auth->mech); 921err_free: 922 kfree(gss_auth); 923out_dec: 924 module_put(THIS_MODULE); 925 return ERR_PTR(err); 926} 927 928static void 929gss_free(struct gss_auth *gss_auth) 930{ 931 gss_pipes_dentries_destroy_net(gss_auth->client, &gss_auth->rpc_auth); 932 rpc_destroy_pipe_data(gss_auth->pipe[0]); 933 rpc_destroy_pipe_data(gss_auth->pipe[1]); 934 gss_mech_put(gss_auth->mech); 935 936 kfree(gss_auth); 937 module_put(THIS_MODULE); 938} 939 940static void 941gss_free_callback(struct kref *kref) 942{ 943 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 944 945 gss_free(gss_auth); 946} 947 948static void 949gss_destroy(struct rpc_auth *auth) 950{ 951 struct gss_auth *gss_auth; 952 953 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 954 auth, auth->au_flavor); 955 956 rpcauth_destroy_credcache(auth); 957 958 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 959 kref_put(&gss_auth->kref, gss_free_callback); 960} 961 962/* 963 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 964 * to the server with the GSS control procedure field set to 965 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 966 * all RPCSEC_GSS state associated with that context. 967 */ 968static int 969gss_destroying_context(struct rpc_cred *cred) 970{ 971 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 972 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 973 struct rpc_task *task; 974 975 if (gss_cred->gc_ctx == NULL || 976 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 977 return 0; 978 979 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 980 cred->cr_ops = &gss_nullops; 981 982 /* Take a reference to ensure the cred will be destroyed either 983 * by the RPC call or by the put_rpccred() below */ 984 get_rpccred(cred); 985 986 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 987 if (!IS_ERR(task)) 988 rpc_put_task(task); 989 990 put_rpccred(cred); 991 return 1; 992} 993 994/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 995 * to create a new cred or context, so they check that things have been 996 * allocated before freeing them. */ 997static void 998gss_do_free_ctx(struct gss_cl_ctx *ctx) 999{ 1000 dprintk("RPC: %s\n", __func__); 1001 1002 gss_delete_sec_context(&ctx->gc_gss_ctx); 1003 kfree(ctx->gc_wire_ctx.data); 1004 kfree(ctx); 1005} 1006 1007static void 1008gss_free_ctx_callback(struct rcu_head *head) 1009{ 1010 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 1011 gss_do_free_ctx(ctx); 1012} 1013 1014static void 1015gss_free_ctx(struct gss_cl_ctx *ctx) 1016{ 1017 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 1018} 1019 1020static void 1021gss_free_cred(struct gss_cred *gss_cred) 1022{ 1023 dprintk("RPC: %s cred=%p\n", __func__, gss_cred); 1024 kfree(gss_cred); 1025} 1026 1027static void 1028gss_free_cred_callback(struct rcu_head *head) 1029{ 1030 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 1031 gss_free_cred(gss_cred); 1032} 1033 1034static void 1035gss_destroy_nullcred(struct rpc_cred *cred) 1036{ 1037 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 1038 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 1039 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 1040 1041 RCU_INIT_POINTER(gss_cred->gc_ctx, NULL); 1042 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 1043 if (ctx) 1044 gss_put_ctx(ctx); 1045 kref_put(&gss_auth->kref, gss_free_callback); 1046} 1047 1048static void 1049gss_destroy_cred(struct rpc_cred *cred) 1050{ 1051 1052 if (gss_destroying_context(cred)) 1053 return; 1054 gss_destroy_nullcred(cred); 1055} 1056 1057/* 1058 * Lookup RPCSEC_GSS cred for the current process 1059 */ 1060static struct rpc_cred * 1061gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1062{ 1063 return rpcauth_lookup_credcache(auth, acred, flags); 1064} 1065 1066static struct rpc_cred * 1067gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1068{ 1069 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1070 struct gss_cred *cred = NULL; 1071 int err = -ENOMEM; 1072 1073 dprintk("RPC: %s for uid %d, flavor %d\n", 1074 __func__, from_kuid(&init_user_ns, acred->uid), 1075 auth->au_flavor); 1076 1077 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 1078 goto out_err; 1079 1080 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 1081 /* 1082 * Note: in order to force a call to call_refresh(), we deliberately 1083 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 1084 */ 1085 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 1086 cred->gc_service = gss_auth->service; 1087 cred->gc_principal = NULL; 1088 if (acred->machine_cred) 1089 cred->gc_principal = acred->principal; 1090 kref_get(&gss_auth->kref); 1091 return &cred->gc_base; 1092 1093out_err: 1094 dprintk("RPC: %s failed with error %d\n", __func__, err); 1095 return ERR_PTR(err); 1096} 1097 1098static int 1099gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1100{ 1101 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1102 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1103 int err; 1104 1105 do { 1106 err = gss_create_upcall(gss_auth, gss_cred); 1107 } while (err == -EAGAIN); 1108 return err; 1109} 1110 1111static int 1112gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1113{ 1114 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1115 1116 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1117 goto out; 1118 /* Don't match with creds that have expired. */ 1119 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1120 return 0; 1121 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1122 return 0; 1123out: 1124 if (acred->principal != NULL) { 1125 if (gss_cred->gc_principal == NULL) 1126 return 0; 1127 return strcmp(acred->principal, gss_cred->gc_principal) == 0; 1128 } 1129 if (gss_cred->gc_principal != NULL) 1130 return 0; 1131 return uid_eq(rc->cr_uid, acred->uid); 1132} 1133 1134/* 1135* Marshal credentials. 1136* Maybe we should keep a cached credential for performance reasons. 1137*/ 1138static __be32 * 1139gss_marshal(struct rpc_task *task, __be32 *p) 1140{ 1141 struct rpc_rqst *req = task->tk_rqstp; 1142 struct rpc_cred *cred = req->rq_cred; 1143 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1144 gc_base); 1145 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1146 __be32 *cred_len; 1147 u32 maj_stat = 0; 1148 struct xdr_netobj mic; 1149 struct kvec iov; 1150 struct xdr_buf verf_buf; 1151 1152 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1153 1154 *p++ = htonl(RPC_AUTH_GSS); 1155 cred_len = p++; 1156 1157 spin_lock(&ctx->gc_seq_lock); 1158 req->rq_seqno = ctx->gc_seq++; 1159 spin_unlock(&ctx->gc_seq_lock); 1160 1161 *p++ = htonl((u32) RPC_GSS_VERSION); 1162 *p++ = htonl((u32) ctx->gc_proc); 1163 *p++ = htonl((u32) req->rq_seqno); 1164 *p++ = htonl((u32) gss_cred->gc_service); 1165 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1166 *cred_len = htonl((p - (cred_len + 1)) << 2); 1167 1168 /* We compute the checksum for the verifier over the xdr-encoded bytes 1169 * starting with the xid and ending at the end of the credential: */ 1170 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 1171 req->rq_snd_buf.head[0].iov_base); 1172 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1173 xdr_buf_from_iov(&iov, &verf_buf); 1174 1175 /* set verifier flavor*/ 1176 *p++ = htonl(RPC_AUTH_GSS); 1177 1178 mic.data = (u8 *)(p + 1); 1179 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1180 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1181 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1182 } else if (maj_stat != 0) { 1183 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1184 goto out_put_ctx; 1185 } 1186 p = xdr_encode_opaque(p, NULL, mic.len); 1187 gss_put_ctx(ctx); 1188 return p; 1189out_put_ctx: 1190 gss_put_ctx(ctx); 1191 return NULL; 1192} 1193 1194static int gss_renew_cred(struct rpc_task *task) 1195{ 1196 struct rpc_cred *oldcred = task->tk_rqstp->rq_cred; 1197 struct gss_cred *gss_cred = container_of(oldcred, 1198 struct gss_cred, 1199 gc_base); 1200 struct rpc_auth *auth = oldcred->cr_auth; 1201 struct auth_cred acred = { 1202 .uid = oldcred->cr_uid, 1203 .principal = gss_cred->gc_principal, 1204 .machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0), 1205 }; 1206 struct rpc_cred *new; 1207 1208 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1209 if (IS_ERR(new)) 1210 return PTR_ERR(new); 1211 task->tk_rqstp->rq_cred = new; 1212 put_rpccred(oldcred); 1213 return 0; 1214} 1215 1216static int gss_cred_is_negative_entry(struct rpc_cred *cred) 1217{ 1218 if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) { 1219 unsigned long now = jiffies; 1220 unsigned long begin, expire; 1221 struct gss_cred *gss_cred; 1222 1223 gss_cred = container_of(cred, struct gss_cred, gc_base); 1224 begin = gss_cred->gc_upcall_timestamp; 1225 expire = begin + gss_expired_cred_retry_delay * HZ; 1226 1227 if (time_in_range_open(now, begin, expire)) 1228 return 1; 1229 } 1230 return 0; 1231} 1232 1233/* 1234* Refresh credentials. XXX - finish 1235*/ 1236static int 1237gss_refresh(struct rpc_task *task) 1238{ 1239 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1240 int ret = 0; 1241 1242 if (gss_cred_is_negative_entry(cred)) 1243 return -EKEYEXPIRED; 1244 1245 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1246 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1247 ret = gss_renew_cred(task); 1248 if (ret < 0) 1249 goto out; 1250 cred = task->tk_rqstp->rq_cred; 1251 } 1252 1253 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1254 ret = gss_refresh_upcall(task); 1255out: 1256 return ret; 1257} 1258 1259/* Dummy refresh routine: used only when destroying the context */ 1260static int 1261gss_refresh_null(struct rpc_task *task) 1262{ 1263 return -EACCES; 1264} 1265 1266static __be32 * 1267gss_validate(struct rpc_task *task, __be32 *p) 1268{ 1269 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1270 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1271 __be32 seq; 1272 struct kvec iov; 1273 struct xdr_buf verf_buf; 1274 struct xdr_netobj mic; 1275 u32 flav,len; 1276 u32 maj_stat; 1277 1278 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1279 1280 flav = ntohl(*p++); 1281 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1282 goto out_bad; 1283 if (flav != RPC_AUTH_GSS) 1284 goto out_bad; 1285 seq = htonl(task->tk_rqstp->rq_seqno); 1286 iov.iov_base = &seq; 1287 iov.iov_len = sizeof(seq); 1288 xdr_buf_from_iov(&iov, &verf_buf); 1289 mic.data = (u8 *)p; 1290 mic.len = len; 1291 1292 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1293 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1294 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1295 if (maj_stat) { 1296 dprintk("RPC: %5u %s: gss_verify_mic returned error 0x%08x\n", 1297 task->tk_pid, __func__, maj_stat); 1298 goto out_bad; 1299 } 1300 /* We leave it to unwrap to calculate au_rslack. For now we just 1301 * calculate the length of the verifier: */ 1302 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1303 gss_put_ctx(ctx); 1304 dprintk("RPC: %5u %s: gss_verify_mic succeeded.\n", 1305 task->tk_pid, __func__); 1306 return p + XDR_QUADLEN(len); 1307out_bad: 1308 gss_put_ctx(ctx); 1309 dprintk("RPC: %5u %s failed.\n", task->tk_pid, __func__); 1310 return NULL; 1311} 1312 1313static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp, 1314 __be32 *p, void *obj) 1315{ 1316 struct xdr_stream xdr; 1317 1318 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, p); 1319 encode(rqstp, &xdr, obj); 1320} 1321 1322static inline int 1323gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1324 kxdreproc_t encode, struct rpc_rqst *rqstp, 1325 __be32 *p, void *obj) 1326{ 1327 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1328 struct xdr_buf integ_buf; 1329 __be32 *integ_len = NULL; 1330 struct xdr_netobj mic; 1331 u32 offset; 1332 __be32 *q; 1333 struct kvec *iov; 1334 u32 maj_stat = 0; 1335 int status = -EIO; 1336 1337 integ_len = p++; 1338 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1339 *p++ = htonl(rqstp->rq_seqno); 1340 1341 gss_wrap_req_encode(encode, rqstp, p, obj); 1342 1343 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1344 offset, snd_buf->len - offset)) 1345 return status; 1346 *integ_len = htonl(integ_buf.len); 1347 1348 /* guess whether we're in the head or the tail: */ 1349 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1350 iov = snd_buf->tail; 1351 else 1352 iov = snd_buf->head; 1353 p = iov->iov_base + iov->iov_len; 1354 mic.data = (u8 *)(p + 1); 1355 1356 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1357 status = -EIO; /* XXX? */ 1358 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1359 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1360 else if (maj_stat) 1361 return status; 1362 q = xdr_encode_opaque(p, NULL, mic.len); 1363 1364 offset = (u8 *)q - (u8 *)p; 1365 iov->iov_len += offset; 1366 snd_buf->len += offset; 1367 return 0; 1368} 1369 1370static void 1371priv_release_snd_buf(struct rpc_rqst *rqstp) 1372{ 1373 int i; 1374 1375 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1376 __free_page(rqstp->rq_enc_pages[i]); 1377 kfree(rqstp->rq_enc_pages); 1378} 1379 1380static int 1381alloc_enc_pages(struct rpc_rqst *rqstp) 1382{ 1383 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1384 int first, last, i; 1385 1386 if (snd_buf->page_len == 0) { 1387 rqstp->rq_enc_pages_num = 0; 1388 return 0; 1389 } 1390 1391 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1392 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1393 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1394 rqstp->rq_enc_pages 1395 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1396 GFP_NOFS); 1397 if (!rqstp->rq_enc_pages) 1398 goto out; 1399 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1400 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1401 if (rqstp->rq_enc_pages[i] == NULL) 1402 goto out_free; 1403 } 1404 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1405 return 0; 1406out_free: 1407 rqstp->rq_enc_pages_num = i; 1408 priv_release_snd_buf(rqstp); 1409out: 1410 return -EAGAIN; 1411} 1412 1413static inline int 1414gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1415 kxdreproc_t encode, struct rpc_rqst *rqstp, 1416 __be32 *p, void *obj) 1417{ 1418 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1419 u32 offset; 1420 u32 maj_stat; 1421 int status; 1422 __be32 *opaque_len; 1423 struct page **inpages; 1424 int first; 1425 int pad; 1426 struct kvec *iov; 1427 char *tmp; 1428 1429 opaque_len = p++; 1430 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1431 *p++ = htonl(rqstp->rq_seqno); 1432 1433 gss_wrap_req_encode(encode, rqstp, p, obj); 1434 1435 status = alloc_enc_pages(rqstp); 1436 if (status) 1437 return status; 1438 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1439 inpages = snd_buf->pages + first; 1440 snd_buf->pages = rqstp->rq_enc_pages; 1441 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1442 /* 1443 * Give the tail its own page, in case we need extra space in the 1444 * head when wrapping: 1445 * 1446 * call_allocate() allocates twice the slack space required 1447 * by the authentication flavor to rq_callsize. 1448 * For GSS, slack is GSS_CRED_SLACK. 1449 */ 1450 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1451 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1452 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1453 snd_buf->tail[0].iov_base = tmp; 1454 } 1455 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1456 /* slack space should prevent this ever happening: */ 1457 BUG_ON(snd_buf->len > snd_buf->buflen); 1458 status = -EIO; 1459 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1460 * done anyway, so it's safe to put the request on the wire: */ 1461 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1462 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1463 else if (maj_stat) 1464 return status; 1465 1466 *opaque_len = htonl(snd_buf->len - offset); 1467 /* guess whether we're in the head or the tail: */ 1468 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1469 iov = snd_buf->tail; 1470 else 1471 iov = snd_buf->head; 1472 p = iov->iov_base + iov->iov_len; 1473 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1474 memset(p, 0, pad); 1475 iov->iov_len += pad; 1476 snd_buf->len += pad; 1477 1478 return 0; 1479} 1480 1481static int 1482gss_wrap_req(struct rpc_task *task, 1483 kxdreproc_t encode, void *rqstp, __be32 *p, void *obj) 1484{ 1485 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1486 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1487 gc_base); 1488 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1489 int status = -EIO; 1490 1491 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1492 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1493 /* The spec seems a little ambiguous here, but I think that not 1494 * wrapping context destruction requests makes the most sense. 1495 */ 1496 gss_wrap_req_encode(encode, rqstp, p, obj); 1497 status = 0; 1498 goto out; 1499 } 1500 switch (gss_cred->gc_service) { 1501 case RPC_GSS_SVC_NONE: 1502 gss_wrap_req_encode(encode, rqstp, p, obj); 1503 status = 0; 1504 break; 1505 case RPC_GSS_SVC_INTEGRITY: 1506 status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj); 1507 break; 1508 case RPC_GSS_SVC_PRIVACY: 1509 status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj); 1510 break; 1511 } 1512out: 1513 gss_put_ctx(ctx); 1514 dprintk("RPC: %5u %s returning %d\n", task->tk_pid, __func__, status); 1515 return status; 1516} 1517 1518static inline int 1519gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1520 struct rpc_rqst *rqstp, __be32 **p) 1521{ 1522 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1523 struct xdr_buf integ_buf; 1524 struct xdr_netobj mic; 1525 u32 data_offset, mic_offset; 1526 u32 integ_len; 1527 u32 maj_stat; 1528 int status = -EIO; 1529 1530 integ_len = ntohl(*(*p)++); 1531 if (integ_len & 3) 1532 return status; 1533 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1534 mic_offset = integ_len + data_offset; 1535 if (mic_offset > rcv_buf->len) 1536 return status; 1537 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1538 return status; 1539 1540 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1541 mic_offset - data_offset)) 1542 return status; 1543 1544 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1545 return status; 1546 1547 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1548 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1549 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1550 if (maj_stat != GSS_S_COMPLETE) 1551 return status; 1552 return 0; 1553} 1554 1555static inline int 1556gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1557 struct rpc_rqst *rqstp, __be32 **p) 1558{ 1559 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1560 u32 offset; 1561 u32 opaque_len; 1562 u32 maj_stat; 1563 int status = -EIO; 1564 1565 opaque_len = ntohl(*(*p)++); 1566 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1567 if (offset + opaque_len > rcv_buf->len) 1568 return status; 1569 /* remove padding: */ 1570 rcv_buf->len = offset + opaque_len; 1571 1572 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1573 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1574 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1575 if (maj_stat != GSS_S_COMPLETE) 1576 return status; 1577 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1578 return status; 1579 1580 return 0; 1581} 1582 1583static int 1584gss_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp, 1585 __be32 *p, void *obj) 1586{ 1587 struct xdr_stream xdr; 1588 1589 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); 1590 return decode(rqstp, &xdr, obj); 1591} 1592 1593static int 1594gss_unwrap_resp(struct rpc_task *task, 1595 kxdrdproc_t decode, void *rqstp, __be32 *p, void *obj) 1596{ 1597 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1598 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1599 gc_base); 1600 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1601 __be32 *savedp = p; 1602 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1603 int savedlen = head->iov_len; 1604 int status = -EIO; 1605 1606 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1607 goto out_decode; 1608 switch (gss_cred->gc_service) { 1609 case RPC_GSS_SVC_NONE: 1610 break; 1611 case RPC_GSS_SVC_INTEGRITY: 1612 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1613 if (status) 1614 goto out; 1615 break; 1616 case RPC_GSS_SVC_PRIVACY: 1617 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1618 if (status) 1619 goto out; 1620 break; 1621 } 1622 /* take into account extra slack for integrity and privacy cases: */ 1623 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1624 + (savedlen - head->iov_len); 1625out_decode: 1626 status = gss_unwrap_req_decode(decode, rqstp, p, obj); 1627out: 1628 gss_put_ctx(ctx); 1629 dprintk("RPC: %5u %s returning %d\n", 1630 task->tk_pid, __func__, status); 1631 return status; 1632} 1633 1634static const struct rpc_authops authgss_ops = { 1635 .owner = THIS_MODULE, 1636 .au_flavor = RPC_AUTH_GSS, 1637 .au_name = "RPCSEC_GSS", 1638 .create = gss_create, 1639 .destroy = gss_destroy, 1640 .lookup_cred = gss_lookup_cred, 1641 .crcreate = gss_create_cred, 1642 .pipes_create = gss_pipes_dentries_create, 1643 .pipes_destroy = gss_pipes_dentries_destroy, 1644 .list_pseudoflavors = gss_mech_list_pseudoflavors, 1645}; 1646 1647static const struct rpc_credops gss_credops = { 1648 .cr_name = "AUTH_GSS", 1649 .crdestroy = gss_destroy_cred, 1650 .cr_init = gss_cred_init, 1651 .crbind = rpcauth_generic_bind_cred, 1652 .crmatch = gss_match, 1653 .crmarshal = gss_marshal, 1654 .crrefresh = gss_refresh, 1655 .crvalidate = gss_validate, 1656 .crwrap_req = gss_wrap_req, 1657 .crunwrap_resp = gss_unwrap_resp, 1658}; 1659 1660static const struct rpc_credops gss_nullops = { 1661 .cr_name = "AUTH_GSS", 1662 .crdestroy = gss_destroy_nullcred, 1663 .crbind = rpcauth_generic_bind_cred, 1664 .crmatch = gss_match, 1665 .crmarshal = gss_marshal, 1666 .crrefresh = gss_refresh_null, 1667 .crvalidate = gss_validate, 1668 .crwrap_req = gss_wrap_req, 1669 .crunwrap_resp = gss_unwrap_resp, 1670}; 1671 1672static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 1673 .upcall = rpc_pipe_generic_upcall, 1674 .downcall = gss_pipe_downcall, 1675 .destroy_msg = gss_pipe_destroy_msg, 1676 .open_pipe = gss_pipe_open_v0, 1677 .release_pipe = gss_pipe_release, 1678}; 1679 1680static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 1681 .upcall = rpc_pipe_generic_upcall, 1682 .downcall = gss_pipe_downcall, 1683 .destroy_msg = gss_pipe_destroy_msg, 1684 .open_pipe = gss_pipe_open_v1, 1685 .release_pipe = gss_pipe_release, 1686}; 1687 1688static __net_init int rpcsec_gss_init_net(struct net *net) 1689{ 1690 return gss_svc_init_net(net); 1691} 1692 1693static __net_exit void rpcsec_gss_exit_net(struct net *net) 1694{ 1695 gss_svc_shutdown_net(net); 1696} 1697 1698static struct pernet_operations rpcsec_gss_net_ops = { 1699 .init = rpcsec_gss_init_net, 1700 .exit = rpcsec_gss_exit_net, 1701}; 1702 1703/* 1704 * Initialize RPCSEC_GSS module 1705 */ 1706static int __init init_rpcsec_gss(void) 1707{ 1708 int err = 0; 1709 1710 err = rpcauth_register(&authgss_ops); 1711 if (err) 1712 goto out; 1713 err = gss_svc_init(); 1714 if (err) 1715 goto out_unregister; 1716 err = register_pernet_subsys(&rpcsec_gss_net_ops); 1717 if (err) 1718 goto out_svc_exit; 1719 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1720 return 0; 1721out_svc_exit: 1722 gss_svc_shutdown(); 1723out_unregister: 1724 rpcauth_unregister(&authgss_ops); 1725out: 1726 return err; 1727} 1728 1729static void __exit exit_rpcsec_gss(void) 1730{ 1731 unregister_pernet_subsys(&rpcsec_gss_net_ops); 1732 gss_svc_shutdown(); 1733 rpcauth_unregister(&authgss_ops); 1734 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1735} 1736 1737MODULE_LICENSE("GPL"); 1738module_param_named(expired_cred_retry_delay, 1739 gss_expired_cred_retry_delay, 1740 uint, 0644); 1741MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until " 1742 "the RPC engine retries an expired credential"); 1743 1744module_init(init_rpcsec_gss) 1745module_exit(exit_rpcsec_gss) 1746