auth_gss.c revision 400f26b542e86995662a0cc5483656b7b1f42af6
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, NULL, 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 error %ld\n", __func__, -PTR_ERR(p)); 251 return p; 252} 253 254#define UPCALL_BUF_LEN 128 255 256struct gss_upcall_msg { 257 atomic_t count; 258 kuid_t uid; 259 struct rpc_pipe_msg msg; 260 struct list_head list; 261 struct gss_auth *auth; 262 struct rpc_pipe *pipe; 263 struct rpc_wait_queue rpc_waitqueue; 264 wait_queue_head_t waitqueue; 265 struct gss_cl_ctx *ctx; 266 char databuf[UPCALL_BUF_LEN]; 267}; 268 269static int get_pipe_version(void) 270{ 271 int ret; 272 273 spin_lock(&pipe_version_lock); 274 if (pipe_version >= 0) { 275 atomic_inc(&pipe_users); 276 ret = pipe_version; 277 } else 278 ret = -EAGAIN; 279 spin_unlock(&pipe_version_lock); 280 return ret; 281} 282 283static void put_pipe_version(void) 284{ 285 if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) { 286 pipe_version = -1; 287 spin_unlock(&pipe_version_lock); 288 } 289} 290 291static void 292gss_release_msg(struct gss_upcall_msg *gss_msg) 293{ 294 if (!atomic_dec_and_test(&gss_msg->count)) 295 return; 296 put_pipe_version(); 297 BUG_ON(!list_empty(&gss_msg->list)); 298 if (gss_msg->ctx != NULL) 299 gss_put_ctx(gss_msg->ctx); 300 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue); 301 kfree(gss_msg); 302} 303 304static struct gss_upcall_msg * 305__gss_find_upcall(struct rpc_pipe *pipe, kuid_t uid) 306{ 307 struct gss_upcall_msg *pos; 308 list_for_each_entry(pos, &pipe->in_downcall, list) { 309 if (!uid_eq(pos->uid, uid)) 310 continue; 311 atomic_inc(&pos->count); 312 dprintk("RPC: %s found msg %p\n", __func__, pos); 313 return pos; 314 } 315 dprintk("RPC: %s found nothing\n", __func__); 316 return NULL; 317} 318 319/* Try to add an upcall to the pipefs queue. 320 * If an upcall owned by our uid already exists, then we return a reference 321 * to that upcall instead of adding the new upcall. 322 */ 323static inline struct gss_upcall_msg * 324gss_add_msg(struct gss_upcall_msg *gss_msg) 325{ 326 struct rpc_pipe *pipe = gss_msg->pipe; 327 struct gss_upcall_msg *old; 328 329 spin_lock(&pipe->lock); 330 old = __gss_find_upcall(pipe, gss_msg->uid); 331 if (old == NULL) { 332 atomic_inc(&gss_msg->count); 333 list_add(&gss_msg->list, &pipe->in_downcall); 334 } else 335 gss_msg = old; 336 spin_unlock(&pipe->lock); 337 return gss_msg; 338} 339 340static void 341__gss_unhash_msg(struct gss_upcall_msg *gss_msg) 342{ 343 list_del_init(&gss_msg->list); 344 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 345 wake_up_all(&gss_msg->waitqueue); 346 atomic_dec(&gss_msg->count); 347} 348 349static void 350gss_unhash_msg(struct gss_upcall_msg *gss_msg) 351{ 352 struct rpc_pipe *pipe = gss_msg->pipe; 353 354 if (list_empty(&gss_msg->list)) 355 return; 356 spin_lock(&pipe->lock); 357 if (!list_empty(&gss_msg->list)) 358 __gss_unhash_msg(gss_msg); 359 spin_unlock(&pipe->lock); 360} 361 362static void 363gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg) 364{ 365 switch (gss_msg->msg.errno) { 366 case 0: 367 if (gss_msg->ctx == NULL) 368 break; 369 clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 370 gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx); 371 break; 372 case -EKEYEXPIRED: 373 set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 374 } 375 gss_cred->gc_upcall_timestamp = jiffies; 376 gss_cred->gc_upcall = NULL; 377 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 378} 379 380static void 381gss_upcall_callback(struct rpc_task *task) 382{ 383 struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred, 384 struct gss_cred, gc_base); 385 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 386 struct rpc_pipe *pipe = gss_msg->pipe; 387 388 spin_lock(&pipe->lock); 389 gss_handle_downcall_result(gss_cred, gss_msg); 390 spin_unlock(&pipe->lock); 391 task->tk_status = gss_msg->msg.errno; 392 gss_release_msg(gss_msg); 393} 394 395static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 396{ 397 uid_t uid = from_kuid(&init_user_ns, gss_msg->uid); 398 memcpy(gss_msg->databuf, &uid, sizeof(uid)); 399 gss_msg->msg.data = gss_msg->databuf; 400 gss_msg->msg.len = sizeof(uid); 401 BUG_ON(sizeof(uid) > UPCALL_BUF_LEN); 402} 403 404static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 405 struct rpc_clnt *clnt, 406 const char *service_name) 407{ 408 struct gss_api_mech *mech = gss_msg->auth->mech; 409 char *p = gss_msg->databuf; 410 int len = 0; 411 412 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ", 413 mech->gm_name, 414 from_kuid(&init_user_ns, gss_msg->uid)); 415 p += gss_msg->msg.len; 416 if (clnt->cl_principal) { 417 len = sprintf(p, "target=%s ", clnt->cl_principal); 418 p += len; 419 gss_msg->msg.len += len; 420 } 421 if (service_name != NULL) { 422 len = sprintf(p, "service=%s ", service_name); 423 p += len; 424 gss_msg->msg.len += len; 425 } 426 if (mech->gm_upcall_enctypes) { 427 len = sprintf(p, "enctypes=%s ", mech->gm_upcall_enctypes); 428 p += len; 429 gss_msg->msg.len += len; 430 } 431 len = sprintf(p, "\n"); 432 gss_msg->msg.len += len; 433 434 gss_msg->msg.data = gss_msg->databuf; 435 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); 436} 437 438static void gss_encode_msg(struct gss_upcall_msg *gss_msg, 439 struct rpc_clnt *clnt, 440 const char *service_name) 441{ 442 if (pipe_version == 0) 443 gss_encode_v0_msg(gss_msg); 444 else /* pipe_version == 1 */ 445 gss_encode_v1_msg(gss_msg, clnt, service_name); 446} 447 448static struct gss_upcall_msg * 449gss_alloc_msg(struct gss_auth *gss_auth, struct rpc_clnt *clnt, 450 kuid_t uid, const char *service_name) 451{ 452 struct gss_upcall_msg *gss_msg; 453 int vers; 454 455 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 456 if (gss_msg == NULL) 457 return ERR_PTR(-ENOMEM); 458 vers = get_pipe_version(); 459 if (vers < 0) { 460 kfree(gss_msg); 461 return ERR_PTR(vers); 462 } 463 gss_msg->pipe = gss_auth->pipe[vers]; 464 INIT_LIST_HEAD(&gss_msg->list); 465 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 466 init_waitqueue_head(&gss_msg->waitqueue); 467 atomic_set(&gss_msg->count, 1); 468 gss_msg->uid = uid; 469 gss_msg->auth = gss_auth; 470 gss_encode_msg(gss_msg, clnt, service_name); 471 return gss_msg; 472} 473 474static struct gss_upcall_msg * 475gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 476{ 477 struct gss_cred *gss_cred = container_of(cred, 478 struct gss_cred, gc_base); 479 struct gss_upcall_msg *gss_new, *gss_msg; 480 kuid_t uid = cred->cr_uid; 481 482 gss_new = gss_alloc_msg(gss_auth, clnt, uid, gss_cred->gc_principal); 483 if (IS_ERR(gss_new)) 484 return gss_new; 485 gss_msg = gss_add_msg(gss_new); 486 if (gss_msg == gss_new) { 487 int res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg); 488 if (res) { 489 gss_unhash_msg(gss_new); 490 gss_msg = ERR_PTR(res); 491 } 492 } else 493 gss_release_msg(gss_new); 494 return gss_msg; 495} 496 497static void warn_gssd(void) 498{ 499 static unsigned long ratelimit; 500 unsigned long now = jiffies; 501 502 if (time_after(now, ratelimit)) { 503 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 504 "Please check user daemon is running.\n"); 505 ratelimit = now + 15*HZ; 506 } 507} 508 509static inline int 510gss_refresh_upcall(struct rpc_task *task) 511{ 512 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 513 struct gss_auth *gss_auth = container_of(cred->cr_auth, 514 struct gss_auth, rpc_auth); 515 struct gss_cred *gss_cred = container_of(cred, 516 struct gss_cred, gc_base); 517 struct gss_upcall_msg *gss_msg; 518 struct rpc_pipe *pipe; 519 int err = 0; 520 521 dprintk("RPC: %5u %s for uid %u\n", 522 task->tk_pid, __func__, from_kuid(&init_user_ns, cred->cr_uid)); 523 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 524 if (PTR_ERR(gss_msg) == -EAGAIN) { 525 /* XXX: warning on the first, under the assumption we 526 * shouldn't normally hit this case on a refresh. */ 527 warn_gssd(); 528 task->tk_timeout = 15*HZ; 529 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 530 return -EAGAIN; 531 } 532 if (IS_ERR(gss_msg)) { 533 err = PTR_ERR(gss_msg); 534 goto out; 535 } 536 pipe = gss_msg->pipe; 537 spin_lock(&pipe->lock); 538 if (gss_cred->gc_upcall != NULL) 539 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 540 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { 541 task->tk_timeout = 0; 542 gss_cred->gc_upcall = gss_msg; 543 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 544 atomic_inc(&gss_msg->count); 545 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 546 } else { 547 gss_handle_downcall_result(gss_cred, gss_msg); 548 err = gss_msg->msg.errno; 549 } 550 spin_unlock(&pipe->lock); 551 gss_release_msg(gss_msg); 552out: 553 dprintk("RPC: %5u %s for uid %u result %d\n", 554 task->tk_pid, __func__, 555 from_kuid(&init_user_ns, cred->cr_uid), err); 556 return err; 557} 558 559static inline int 560gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 561{ 562 struct rpc_pipe *pipe; 563 struct rpc_cred *cred = &gss_cred->gc_base; 564 struct gss_upcall_msg *gss_msg; 565 DEFINE_WAIT(wait); 566 int err = 0; 567 568 dprintk("RPC: %s for uid %u\n", 569 __func__, from_kuid(&init_user_ns, cred->cr_uid)); 570retry: 571 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 572 if (PTR_ERR(gss_msg) == -EAGAIN) { 573 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 574 pipe_version >= 0, 15*HZ); 575 if (pipe_version < 0) { 576 warn_gssd(); 577 err = -EACCES; 578 } 579 if (err) 580 goto out; 581 goto retry; 582 } 583 if (IS_ERR(gss_msg)) { 584 err = PTR_ERR(gss_msg); 585 goto out; 586 } 587 pipe = gss_msg->pipe; 588 for (;;) { 589 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE); 590 spin_lock(&pipe->lock); 591 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 592 break; 593 } 594 spin_unlock(&pipe->lock); 595 if (fatal_signal_pending(current)) { 596 err = -ERESTARTSYS; 597 goto out_intr; 598 } 599 schedule(); 600 } 601 if (gss_msg->ctx) 602 gss_cred_set_ctx(cred, gss_msg->ctx); 603 else 604 err = gss_msg->msg.errno; 605 spin_unlock(&pipe->lock); 606out_intr: 607 finish_wait(&gss_msg->waitqueue, &wait); 608 gss_release_msg(gss_msg); 609out: 610 dprintk("RPC: %s for uid %u result %d\n", 611 __func__, from_kuid(&init_user_ns, cred->cr_uid), err); 612 return err; 613} 614 615#define MSG_BUF_MAXSIZE 1024 616 617static ssize_t 618gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 619{ 620 const void *p, *end; 621 void *buf; 622 struct gss_upcall_msg *gss_msg; 623 struct rpc_pipe *pipe = RPC_I(file_inode(filp))->pipe; 624 struct gss_cl_ctx *ctx; 625 uid_t id; 626 kuid_t uid; 627 ssize_t err = -EFBIG; 628 629 if (mlen > MSG_BUF_MAXSIZE) 630 goto out; 631 err = -ENOMEM; 632 buf = kmalloc(mlen, GFP_NOFS); 633 if (!buf) 634 goto out; 635 636 err = -EFAULT; 637 if (copy_from_user(buf, src, mlen)) 638 goto err; 639 640 end = (const void *)((char *)buf + mlen); 641 p = simple_get_bytes(buf, end, &id, sizeof(id)); 642 if (IS_ERR(p)) { 643 err = PTR_ERR(p); 644 goto err; 645 } 646 647 uid = make_kuid(&init_user_ns, id); 648 if (!uid_valid(uid)) { 649 err = -EINVAL; 650 goto err; 651 } 652 653 err = -ENOMEM; 654 ctx = gss_alloc_context(); 655 if (ctx == NULL) 656 goto err; 657 658 err = -ENOENT; 659 /* Find a matching upcall */ 660 spin_lock(&pipe->lock); 661 gss_msg = __gss_find_upcall(pipe, uid); 662 if (gss_msg == NULL) { 663 spin_unlock(&pipe->lock); 664 goto err_put_ctx; 665 } 666 list_del_init(&gss_msg->list); 667 spin_unlock(&pipe->lock); 668 669 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); 670 if (IS_ERR(p)) { 671 err = PTR_ERR(p); 672 switch (err) { 673 case -EACCES: 674 case -EKEYEXPIRED: 675 gss_msg->msg.errno = err; 676 err = mlen; 677 break; 678 case -EFAULT: 679 case -ENOMEM: 680 case -EINVAL: 681 case -ENOSYS: 682 gss_msg->msg.errno = -EAGAIN; 683 break; 684 default: 685 printk(KERN_CRIT "%s: bad return from " 686 "gss_fill_context: %zd\n", __func__, err); 687 BUG(); 688 } 689 goto err_release_msg; 690 } 691 gss_msg->ctx = gss_get_ctx(ctx); 692 err = mlen; 693 694err_release_msg: 695 spin_lock(&pipe->lock); 696 __gss_unhash_msg(gss_msg); 697 spin_unlock(&pipe->lock); 698 gss_release_msg(gss_msg); 699err_put_ctx: 700 gss_put_ctx(ctx); 701err: 702 kfree(buf); 703out: 704 dprintk("RPC: %s returning %Zd\n", __func__, err); 705 return err; 706} 707 708static int gss_pipe_open(struct inode *inode, int new_version) 709{ 710 int ret = 0; 711 712 spin_lock(&pipe_version_lock); 713 if (pipe_version < 0) { 714 /* First open of any gss pipe determines the version: */ 715 pipe_version = new_version; 716 rpc_wake_up(&pipe_version_rpc_waitqueue); 717 wake_up(&pipe_version_waitqueue); 718 } else if (pipe_version != new_version) { 719 /* Trying to open a pipe of a different version */ 720 ret = -EBUSY; 721 goto out; 722 } 723 atomic_inc(&pipe_users); 724out: 725 spin_unlock(&pipe_version_lock); 726 return ret; 727 728} 729 730static int gss_pipe_open_v0(struct inode *inode) 731{ 732 return gss_pipe_open(inode, 0); 733} 734 735static int gss_pipe_open_v1(struct inode *inode) 736{ 737 return gss_pipe_open(inode, 1); 738} 739 740static void 741gss_pipe_release(struct inode *inode) 742{ 743 struct rpc_pipe *pipe = RPC_I(inode)->pipe; 744 struct gss_upcall_msg *gss_msg; 745 746restart: 747 spin_lock(&pipe->lock); 748 list_for_each_entry(gss_msg, &pipe->in_downcall, list) { 749 750 if (!list_empty(&gss_msg->msg.list)) 751 continue; 752 gss_msg->msg.errno = -EPIPE; 753 atomic_inc(&gss_msg->count); 754 __gss_unhash_msg(gss_msg); 755 spin_unlock(&pipe->lock); 756 gss_release_msg(gss_msg); 757 goto restart; 758 } 759 spin_unlock(&pipe->lock); 760 761 put_pipe_version(); 762} 763 764static void 765gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 766{ 767 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 768 769 if (msg->errno < 0) { 770 dprintk("RPC: %s releasing msg %p\n", 771 __func__, gss_msg); 772 atomic_inc(&gss_msg->count); 773 gss_unhash_msg(gss_msg); 774 if (msg->errno == -ETIMEDOUT) 775 warn_gssd(); 776 gss_release_msg(gss_msg); 777 } 778} 779 780static void gss_pipes_dentries_destroy(struct rpc_auth *auth) 781{ 782 struct gss_auth *gss_auth; 783 784 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 785 if (gss_auth->pipe[0]->dentry) 786 rpc_unlink(gss_auth->pipe[0]->dentry); 787 if (gss_auth->pipe[1]->dentry) 788 rpc_unlink(gss_auth->pipe[1]->dentry); 789} 790 791static int gss_pipes_dentries_create(struct rpc_auth *auth) 792{ 793 int err; 794 struct gss_auth *gss_auth; 795 struct rpc_clnt *clnt; 796 797 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 798 clnt = gss_auth->client; 799 800 gss_auth->pipe[1]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry, 801 "gssd", 802 clnt, gss_auth->pipe[1]); 803 if (IS_ERR(gss_auth->pipe[1]->dentry)) 804 return PTR_ERR(gss_auth->pipe[1]->dentry); 805 gss_auth->pipe[0]->dentry = rpc_mkpipe_dentry(clnt->cl_dentry, 806 gss_auth->mech->gm_name, 807 clnt, gss_auth->pipe[0]); 808 if (IS_ERR(gss_auth->pipe[0]->dentry)) { 809 err = PTR_ERR(gss_auth->pipe[0]->dentry); 810 goto err_unlink_pipe_1; 811 } 812 return 0; 813 814err_unlink_pipe_1: 815 rpc_unlink(gss_auth->pipe[1]->dentry); 816 return err; 817} 818 819static void gss_pipes_dentries_destroy_net(struct rpc_clnt *clnt, 820 struct rpc_auth *auth) 821{ 822 struct net *net = rpc_net_ns(clnt); 823 struct super_block *sb; 824 825 sb = rpc_get_sb_net(net); 826 if (sb) { 827 if (clnt->cl_dentry) 828 gss_pipes_dentries_destroy(auth); 829 rpc_put_sb_net(net); 830 } 831} 832 833static int gss_pipes_dentries_create_net(struct rpc_clnt *clnt, 834 struct rpc_auth *auth) 835{ 836 struct net *net = rpc_net_ns(clnt); 837 struct super_block *sb; 838 int err = 0; 839 840 sb = rpc_get_sb_net(net); 841 if (sb) { 842 if (clnt->cl_dentry) 843 err = gss_pipes_dentries_create(auth); 844 rpc_put_sb_net(net); 845 } 846 return err; 847} 848 849/* 850 * NOTE: we have the opportunity to use different 851 * parameters based on the input flavor (which must be a pseudoflavor) 852 */ 853static struct rpc_auth * 854gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 855{ 856 struct gss_auth *gss_auth; 857 struct rpc_auth * auth; 858 int err = -ENOMEM; /* XXX? */ 859 860 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 861 862 if (!try_module_get(THIS_MODULE)) 863 return ERR_PTR(err); 864 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 865 goto out_dec; 866 gss_auth->client = clnt; 867 err = -EINVAL; 868 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 869 if (!gss_auth->mech) { 870 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 871 __func__, flavor); 872 goto err_free; 873 } 874 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 875 if (gss_auth->service == 0) 876 goto err_put_mech; 877 auth = &gss_auth->rpc_auth; 878 auth->au_cslack = GSS_CRED_SLACK >> 2; 879 auth->au_rslack = GSS_VERF_SLACK >> 2; 880 auth->au_ops = &authgss_ops; 881 auth->au_flavor = flavor; 882 atomic_set(&auth->au_count, 1); 883 kref_init(&gss_auth->kref); 884 885 /* 886 * Note: if we created the old pipe first, then someone who 887 * examined the directory at the right moment might conclude 888 * that we supported only the old pipe. So we instead create 889 * the new pipe first. 890 */ 891 gss_auth->pipe[1] = rpc_mkpipe_data(&gss_upcall_ops_v1, 892 RPC_PIPE_WAIT_FOR_OPEN); 893 if (IS_ERR(gss_auth->pipe[1])) { 894 err = PTR_ERR(gss_auth->pipe[1]); 895 goto err_put_mech; 896 } 897 898 gss_auth->pipe[0] = rpc_mkpipe_data(&gss_upcall_ops_v0, 899 RPC_PIPE_WAIT_FOR_OPEN); 900 if (IS_ERR(gss_auth->pipe[0])) { 901 err = PTR_ERR(gss_auth->pipe[0]); 902 goto err_destroy_pipe_1; 903 } 904 err = gss_pipes_dentries_create_net(clnt, auth); 905 if (err) 906 goto err_destroy_pipe_0; 907 err = rpcauth_init_credcache(auth); 908 if (err) 909 goto err_unlink_pipes; 910 911 return auth; 912err_unlink_pipes: 913 gss_pipes_dentries_destroy_net(clnt, auth); 914err_destroy_pipe_0: 915 rpc_destroy_pipe_data(gss_auth->pipe[0]); 916err_destroy_pipe_1: 917 rpc_destroy_pipe_data(gss_auth->pipe[1]); 918err_put_mech: 919 gss_mech_put(gss_auth->mech); 920err_free: 921 kfree(gss_auth); 922out_dec: 923 module_put(THIS_MODULE); 924 return ERR_PTR(err); 925} 926 927static void 928gss_free(struct gss_auth *gss_auth) 929{ 930 gss_pipes_dentries_destroy_net(gss_auth->client, &gss_auth->rpc_auth); 931 rpc_destroy_pipe_data(gss_auth->pipe[0]); 932 rpc_destroy_pipe_data(gss_auth->pipe[1]); 933 gss_mech_put(gss_auth->mech); 934 935 kfree(gss_auth); 936 module_put(THIS_MODULE); 937} 938 939static void 940gss_free_callback(struct kref *kref) 941{ 942 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 943 944 gss_free(gss_auth); 945} 946 947static void 948gss_destroy(struct rpc_auth *auth) 949{ 950 struct gss_auth *gss_auth; 951 952 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 953 auth, auth->au_flavor); 954 955 rpcauth_destroy_credcache(auth); 956 957 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 958 kref_put(&gss_auth->kref, gss_free_callback); 959} 960 961/* 962 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 963 * to the server with the GSS control procedure field set to 964 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 965 * all RPCSEC_GSS state associated with that context. 966 */ 967static int 968gss_destroying_context(struct rpc_cred *cred) 969{ 970 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 971 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 972 struct rpc_task *task; 973 974 if (gss_cred->gc_ctx == NULL || 975 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 976 return 0; 977 978 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 979 cred->cr_ops = &gss_nullops; 980 981 /* Take a reference to ensure the cred will be destroyed either 982 * by the RPC call or by the put_rpccred() below */ 983 get_rpccred(cred); 984 985 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 986 if (!IS_ERR(task)) 987 rpc_put_task(task); 988 989 put_rpccred(cred); 990 return 1; 991} 992 993/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 994 * to create a new cred or context, so they check that things have been 995 * allocated before freeing them. */ 996static void 997gss_do_free_ctx(struct gss_cl_ctx *ctx) 998{ 999 dprintk("RPC: %s\n", __func__); 1000 1001 gss_delete_sec_context(&ctx->gc_gss_ctx); 1002 kfree(ctx->gc_wire_ctx.data); 1003 kfree(ctx); 1004} 1005 1006static void 1007gss_free_ctx_callback(struct rcu_head *head) 1008{ 1009 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 1010 gss_do_free_ctx(ctx); 1011} 1012 1013static void 1014gss_free_ctx(struct gss_cl_ctx *ctx) 1015{ 1016 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 1017} 1018 1019static void 1020gss_free_cred(struct gss_cred *gss_cred) 1021{ 1022 dprintk("RPC: %s cred=%p\n", __func__, gss_cred); 1023 kfree(gss_cred); 1024} 1025 1026static void 1027gss_free_cred_callback(struct rcu_head *head) 1028{ 1029 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 1030 gss_free_cred(gss_cred); 1031} 1032 1033static void 1034gss_destroy_nullcred(struct rpc_cred *cred) 1035{ 1036 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 1037 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 1038 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 1039 1040 RCU_INIT_POINTER(gss_cred->gc_ctx, NULL); 1041 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 1042 if (ctx) 1043 gss_put_ctx(ctx); 1044 kref_put(&gss_auth->kref, gss_free_callback); 1045} 1046 1047static void 1048gss_destroy_cred(struct rpc_cred *cred) 1049{ 1050 1051 if (gss_destroying_context(cred)) 1052 return; 1053 gss_destroy_nullcred(cred); 1054} 1055 1056/* 1057 * Lookup RPCSEC_GSS cred for the current process 1058 */ 1059static struct rpc_cred * 1060gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1061{ 1062 return rpcauth_lookup_credcache(auth, acred, flags); 1063} 1064 1065static struct rpc_cred * 1066gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 1067{ 1068 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1069 struct gss_cred *cred = NULL; 1070 int err = -ENOMEM; 1071 1072 dprintk("RPC: %s for uid %d, flavor %d\n", 1073 __func__, from_kuid(&init_user_ns, acred->uid), 1074 auth->au_flavor); 1075 1076 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 1077 goto out_err; 1078 1079 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 1080 /* 1081 * Note: in order to force a call to call_refresh(), we deliberately 1082 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 1083 */ 1084 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 1085 cred->gc_service = gss_auth->service; 1086 cred->gc_principal = NULL; 1087 if (acred->machine_cred) 1088 cred->gc_principal = acred->principal; 1089 kref_get(&gss_auth->kref); 1090 return &cred->gc_base; 1091 1092out_err: 1093 dprintk("RPC: %s failed with error %d\n", __func__, err); 1094 return ERR_PTR(err); 1095} 1096 1097static int 1098gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1099{ 1100 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1101 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1102 int err; 1103 1104 do { 1105 err = gss_create_upcall(gss_auth, gss_cred); 1106 } while (err == -EAGAIN); 1107 return err; 1108} 1109 1110static int 1111gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1112{ 1113 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1114 1115 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1116 goto out; 1117 /* Don't match with creds that have expired. */ 1118 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1119 return 0; 1120 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1121 return 0; 1122out: 1123 if (acred->principal != NULL) { 1124 if (gss_cred->gc_principal == NULL) 1125 return 0; 1126 return strcmp(acred->principal, gss_cred->gc_principal) == 0; 1127 } 1128 if (gss_cred->gc_principal != NULL) 1129 return 0; 1130 return uid_eq(rc->cr_uid, acred->uid); 1131} 1132 1133/* 1134* Marshal credentials. 1135* Maybe we should keep a cached credential for performance reasons. 1136*/ 1137static __be32 * 1138gss_marshal(struct rpc_task *task, __be32 *p) 1139{ 1140 struct rpc_rqst *req = task->tk_rqstp; 1141 struct rpc_cred *cred = req->rq_cred; 1142 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1143 gc_base); 1144 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1145 __be32 *cred_len; 1146 u32 maj_stat = 0; 1147 struct xdr_netobj mic; 1148 struct kvec iov; 1149 struct xdr_buf verf_buf; 1150 1151 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1152 1153 *p++ = htonl(RPC_AUTH_GSS); 1154 cred_len = p++; 1155 1156 spin_lock(&ctx->gc_seq_lock); 1157 req->rq_seqno = ctx->gc_seq++; 1158 spin_unlock(&ctx->gc_seq_lock); 1159 1160 *p++ = htonl((u32) RPC_GSS_VERSION); 1161 *p++ = htonl((u32) ctx->gc_proc); 1162 *p++ = htonl((u32) req->rq_seqno); 1163 *p++ = htonl((u32) gss_cred->gc_service); 1164 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1165 *cred_len = htonl((p - (cred_len + 1)) << 2); 1166 1167 /* We compute the checksum for the verifier over the xdr-encoded bytes 1168 * starting with the xid and ending at the end of the credential: */ 1169 iov.iov_base = xprt_skip_transport_header(req->rq_xprt, 1170 req->rq_snd_buf.head[0].iov_base); 1171 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1172 xdr_buf_from_iov(&iov, &verf_buf); 1173 1174 /* set verifier flavor*/ 1175 *p++ = htonl(RPC_AUTH_GSS); 1176 1177 mic.data = (u8 *)(p + 1); 1178 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1179 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1180 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1181 } else if (maj_stat != 0) { 1182 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1183 goto out_put_ctx; 1184 } 1185 p = xdr_encode_opaque(p, NULL, mic.len); 1186 gss_put_ctx(ctx); 1187 return p; 1188out_put_ctx: 1189 gss_put_ctx(ctx); 1190 return NULL; 1191} 1192 1193static int gss_renew_cred(struct rpc_task *task) 1194{ 1195 struct rpc_cred *oldcred = task->tk_rqstp->rq_cred; 1196 struct gss_cred *gss_cred = container_of(oldcred, 1197 struct gss_cred, 1198 gc_base); 1199 struct rpc_auth *auth = oldcred->cr_auth; 1200 struct auth_cred acred = { 1201 .uid = oldcred->cr_uid, 1202 .principal = gss_cred->gc_principal, 1203 .machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0), 1204 }; 1205 struct rpc_cred *new; 1206 1207 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1208 if (IS_ERR(new)) 1209 return PTR_ERR(new); 1210 task->tk_rqstp->rq_cred = new; 1211 put_rpccred(oldcred); 1212 return 0; 1213} 1214 1215static int gss_cred_is_negative_entry(struct rpc_cred *cred) 1216{ 1217 if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) { 1218 unsigned long now = jiffies; 1219 unsigned long begin, expire; 1220 struct gss_cred *gss_cred; 1221 1222 gss_cred = container_of(cred, struct gss_cred, gc_base); 1223 begin = gss_cred->gc_upcall_timestamp; 1224 expire = begin + gss_expired_cred_retry_delay * HZ; 1225 1226 if (time_in_range_open(now, begin, expire)) 1227 return 1; 1228 } 1229 return 0; 1230} 1231 1232/* 1233* Refresh credentials. XXX - finish 1234*/ 1235static int 1236gss_refresh(struct rpc_task *task) 1237{ 1238 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1239 int ret = 0; 1240 1241 if (gss_cred_is_negative_entry(cred)) 1242 return -EKEYEXPIRED; 1243 1244 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1245 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1246 ret = gss_renew_cred(task); 1247 if (ret < 0) 1248 goto out; 1249 cred = task->tk_rqstp->rq_cred; 1250 } 1251 1252 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1253 ret = gss_refresh_upcall(task); 1254out: 1255 return ret; 1256} 1257 1258/* Dummy refresh routine: used only when destroying the context */ 1259static int 1260gss_refresh_null(struct rpc_task *task) 1261{ 1262 return -EACCES; 1263} 1264 1265static __be32 * 1266gss_validate(struct rpc_task *task, __be32 *p) 1267{ 1268 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1269 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1270 __be32 seq; 1271 struct kvec iov; 1272 struct xdr_buf verf_buf; 1273 struct xdr_netobj mic; 1274 u32 flav,len; 1275 u32 maj_stat; 1276 1277 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1278 1279 flav = ntohl(*p++); 1280 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1281 goto out_bad; 1282 if (flav != RPC_AUTH_GSS) 1283 goto out_bad; 1284 seq = htonl(task->tk_rqstp->rq_seqno); 1285 iov.iov_base = &seq; 1286 iov.iov_len = sizeof(seq); 1287 xdr_buf_from_iov(&iov, &verf_buf); 1288 mic.data = (u8 *)p; 1289 mic.len = len; 1290 1291 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1292 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1293 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1294 if (maj_stat) { 1295 dprintk("RPC: %5u %s: gss_verify_mic returned error 0x%08x\n", 1296 task->tk_pid, __func__, maj_stat); 1297 goto out_bad; 1298 } 1299 /* We leave it to unwrap to calculate au_rslack. For now we just 1300 * calculate the length of the verifier: */ 1301 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1302 gss_put_ctx(ctx); 1303 dprintk("RPC: %5u %s: gss_verify_mic succeeded.\n", 1304 task->tk_pid, __func__); 1305 return p + XDR_QUADLEN(len); 1306out_bad: 1307 gss_put_ctx(ctx); 1308 dprintk("RPC: %5u %s failed.\n", task->tk_pid, __func__); 1309 return NULL; 1310} 1311 1312static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp, 1313 __be32 *p, void *obj) 1314{ 1315 struct xdr_stream xdr; 1316 1317 xdr_init_encode(&xdr, &rqstp->rq_snd_buf, p); 1318 encode(rqstp, &xdr, obj); 1319} 1320 1321static inline int 1322gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1323 kxdreproc_t encode, struct rpc_rqst *rqstp, 1324 __be32 *p, void *obj) 1325{ 1326 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1327 struct xdr_buf integ_buf; 1328 __be32 *integ_len = NULL; 1329 struct xdr_netobj mic; 1330 u32 offset; 1331 __be32 *q; 1332 struct kvec *iov; 1333 u32 maj_stat = 0; 1334 int status = -EIO; 1335 1336 integ_len = p++; 1337 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1338 *p++ = htonl(rqstp->rq_seqno); 1339 1340 gss_wrap_req_encode(encode, rqstp, p, obj); 1341 1342 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1343 offset, snd_buf->len - offset)) 1344 return status; 1345 *integ_len = htonl(integ_buf.len); 1346 1347 /* guess whether we're in the head or the tail: */ 1348 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1349 iov = snd_buf->tail; 1350 else 1351 iov = snd_buf->head; 1352 p = iov->iov_base + iov->iov_len; 1353 mic.data = (u8 *)(p + 1); 1354 1355 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1356 status = -EIO; /* XXX? */ 1357 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1358 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1359 else if (maj_stat) 1360 return status; 1361 q = xdr_encode_opaque(p, NULL, mic.len); 1362 1363 offset = (u8 *)q - (u8 *)p; 1364 iov->iov_len += offset; 1365 snd_buf->len += offset; 1366 return 0; 1367} 1368 1369static void 1370priv_release_snd_buf(struct rpc_rqst *rqstp) 1371{ 1372 int i; 1373 1374 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1375 __free_page(rqstp->rq_enc_pages[i]); 1376 kfree(rqstp->rq_enc_pages); 1377} 1378 1379static int 1380alloc_enc_pages(struct rpc_rqst *rqstp) 1381{ 1382 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1383 int first, last, i; 1384 1385 if (snd_buf->page_len == 0) { 1386 rqstp->rq_enc_pages_num = 0; 1387 return 0; 1388 } 1389 1390 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1391 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1392 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1393 rqstp->rq_enc_pages 1394 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1395 GFP_NOFS); 1396 if (!rqstp->rq_enc_pages) 1397 goto out; 1398 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1399 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1400 if (rqstp->rq_enc_pages[i] == NULL) 1401 goto out_free; 1402 } 1403 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1404 return 0; 1405out_free: 1406 rqstp->rq_enc_pages_num = i; 1407 priv_release_snd_buf(rqstp); 1408out: 1409 return -EAGAIN; 1410} 1411 1412static inline int 1413gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1414 kxdreproc_t encode, struct rpc_rqst *rqstp, 1415 __be32 *p, void *obj) 1416{ 1417 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1418 u32 offset; 1419 u32 maj_stat; 1420 int status; 1421 __be32 *opaque_len; 1422 struct page **inpages; 1423 int first; 1424 int pad; 1425 struct kvec *iov; 1426 char *tmp; 1427 1428 opaque_len = p++; 1429 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1430 *p++ = htonl(rqstp->rq_seqno); 1431 1432 gss_wrap_req_encode(encode, rqstp, p, obj); 1433 1434 status = alloc_enc_pages(rqstp); 1435 if (status) 1436 return status; 1437 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1438 inpages = snd_buf->pages + first; 1439 snd_buf->pages = rqstp->rq_enc_pages; 1440 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1441 /* 1442 * Give the tail its own page, in case we need extra space in the 1443 * head when wrapping: 1444 * 1445 * call_allocate() allocates twice the slack space required 1446 * by the authentication flavor to rq_callsize. 1447 * For GSS, slack is GSS_CRED_SLACK. 1448 */ 1449 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1450 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1451 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1452 snd_buf->tail[0].iov_base = tmp; 1453 } 1454 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1455 /* slack space should prevent this ever happening: */ 1456 BUG_ON(snd_buf->len > snd_buf->buflen); 1457 status = -EIO; 1458 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1459 * done anyway, so it's safe to put the request on the wire: */ 1460 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1461 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1462 else if (maj_stat) 1463 return status; 1464 1465 *opaque_len = htonl(snd_buf->len - offset); 1466 /* guess whether we're in the head or the tail: */ 1467 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1468 iov = snd_buf->tail; 1469 else 1470 iov = snd_buf->head; 1471 p = iov->iov_base + iov->iov_len; 1472 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1473 memset(p, 0, pad); 1474 iov->iov_len += pad; 1475 snd_buf->len += pad; 1476 1477 return 0; 1478} 1479 1480static int 1481gss_wrap_req(struct rpc_task *task, 1482 kxdreproc_t encode, void *rqstp, __be32 *p, void *obj) 1483{ 1484 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1485 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1486 gc_base); 1487 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1488 int status = -EIO; 1489 1490 dprintk("RPC: %5u %s\n", task->tk_pid, __func__); 1491 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1492 /* The spec seems a little ambiguous here, but I think that not 1493 * wrapping context destruction requests makes the most sense. 1494 */ 1495 gss_wrap_req_encode(encode, rqstp, p, obj); 1496 status = 0; 1497 goto out; 1498 } 1499 switch (gss_cred->gc_service) { 1500 case RPC_GSS_SVC_NONE: 1501 gss_wrap_req_encode(encode, rqstp, p, obj); 1502 status = 0; 1503 break; 1504 case RPC_GSS_SVC_INTEGRITY: 1505 status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj); 1506 break; 1507 case RPC_GSS_SVC_PRIVACY: 1508 status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj); 1509 break; 1510 } 1511out: 1512 gss_put_ctx(ctx); 1513 dprintk("RPC: %5u %s returning %d\n", task->tk_pid, __func__, status); 1514 return status; 1515} 1516 1517static inline int 1518gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1519 struct rpc_rqst *rqstp, __be32 **p) 1520{ 1521 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1522 struct xdr_buf integ_buf; 1523 struct xdr_netobj mic; 1524 u32 data_offset, mic_offset; 1525 u32 integ_len; 1526 u32 maj_stat; 1527 int status = -EIO; 1528 1529 integ_len = ntohl(*(*p)++); 1530 if (integ_len & 3) 1531 return status; 1532 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1533 mic_offset = integ_len + data_offset; 1534 if (mic_offset > rcv_buf->len) 1535 return status; 1536 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1537 return status; 1538 1539 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1540 mic_offset - data_offset)) 1541 return status; 1542 1543 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1544 return status; 1545 1546 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1547 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1548 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1549 if (maj_stat != GSS_S_COMPLETE) 1550 return status; 1551 return 0; 1552} 1553 1554static inline int 1555gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1556 struct rpc_rqst *rqstp, __be32 **p) 1557{ 1558 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1559 u32 offset; 1560 u32 opaque_len; 1561 u32 maj_stat; 1562 int status = -EIO; 1563 1564 opaque_len = ntohl(*(*p)++); 1565 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1566 if (offset + opaque_len > rcv_buf->len) 1567 return status; 1568 /* remove padding: */ 1569 rcv_buf->len = offset + opaque_len; 1570 1571 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1572 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1573 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1574 if (maj_stat != GSS_S_COMPLETE) 1575 return status; 1576 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1577 return status; 1578 1579 return 0; 1580} 1581 1582static int 1583gss_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp, 1584 __be32 *p, void *obj) 1585{ 1586 struct xdr_stream xdr; 1587 1588 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p); 1589 return decode(rqstp, &xdr, obj); 1590} 1591 1592static int 1593gss_unwrap_resp(struct rpc_task *task, 1594 kxdrdproc_t decode, void *rqstp, __be32 *p, void *obj) 1595{ 1596 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1597 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1598 gc_base); 1599 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1600 __be32 *savedp = p; 1601 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1602 int savedlen = head->iov_len; 1603 int status = -EIO; 1604 1605 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1606 goto out_decode; 1607 switch (gss_cred->gc_service) { 1608 case RPC_GSS_SVC_NONE: 1609 break; 1610 case RPC_GSS_SVC_INTEGRITY: 1611 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1612 if (status) 1613 goto out; 1614 break; 1615 case RPC_GSS_SVC_PRIVACY: 1616 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1617 if (status) 1618 goto out; 1619 break; 1620 } 1621 /* take into account extra slack for integrity and privacy cases: */ 1622 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1623 + (savedlen - head->iov_len); 1624out_decode: 1625 status = gss_unwrap_req_decode(decode, rqstp, p, obj); 1626out: 1627 gss_put_ctx(ctx); 1628 dprintk("RPC: %5u %s returning %d\n", 1629 task->tk_pid, __func__, status); 1630 return status; 1631} 1632 1633static const struct rpc_authops authgss_ops = { 1634 .owner = THIS_MODULE, 1635 .au_flavor = RPC_AUTH_GSS, 1636 .au_name = "RPCSEC_GSS", 1637 .create = gss_create, 1638 .destroy = gss_destroy, 1639 .lookup_cred = gss_lookup_cred, 1640 .crcreate = gss_create_cred, 1641 .pipes_create = gss_pipes_dentries_create, 1642 .pipes_destroy = gss_pipes_dentries_destroy, 1643 .list_pseudoflavors = gss_mech_list_pseudoflavors, 1644}; 1645 1646static const struct rpc_credops gss_credops = { 1647 .cr_name = "AUTH_GSS", 1648 .crdestroy = gss_destroy_cred, 1649 .cr_init = gss_cred_init, 1650 .crbind = rpcauth_generic_bind_cred, 1651 .crmatch = gss_match, 1652 .crmarshal = gss_marshal, 1653 .crrefresh = gss_refresh, 1654 .crvalidate = gss_validate, 1655 .crwrap_req = gss_wrap_req, 1656 .crunwrap_resp = gss_unwrap_resp, 1657}; 1658 1659static const struct rpc_credops gss_nullops = { 1660 .cr_name = "AUTH_GSS", 1661 .crdestroy = gss_destroy_nullcred, 1662 .crbind = rpcauth_generic_bind_cred, 1663 .crmatch = gss_match, 1664 .crmarshal = gss_marshal, 1665 .crrefresh = gss_refresh_null, 1666 .crvalidate = gss_validate, 1667 .crwrap_req = gss_wrap_req, 1668 .crunwrap_resp = gss_unwrap_resp, 1669}; 1670 1671static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 1672 .upcall = rpc_pipe_generic_upcall, 1673 .downcall = gss_pipe_downcall, 1674 .destroy_msg = gss_pipe_destroy_msg, 1675 .open_pipe = gss_pipe_open_v0, 1676 .release_pipe = gss_pipe_release, 1677}; 1678 1679static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 1680 .upcall = rpc_pipe_generic_upcall, 1681 .downcall = gss_pipe_downcall, 1682 .destroy_msg = gss_pipe_destroy_msg, 1683 .open_pipe = gss_pipe_open_v1, 1684 .release_pipe = gss_pipe_release, 1685}; 1686 1687static __net_init int rpcsec_gss_init_net(struct net *net) 1688{ 1689 return gss_svc_init_net(net); 1690} 1691 1692static __net_exit void rpcsec_gss_exit_net(struct net *net) 1693{ 1694 gss_svc_shutdown_net(net); 1695} 1696 1697static struct pernet_operations rpcsec_gss_net_ops = { 1698 .init = rpcsec_gss_init_net, 1699 .exit = rpcsec_gss_exit_net, 1700}; 1701 1702/* 1703 * Initialize RPCSEC_GSS module 1704 */ 1705static int __init init_rpcsec_gss(void) 1706{ 1707 int err = 0; 1708 1709 err = rpcauth_register(&authgss_ops); 1710 if (err) 1711 goto out; 1712 err = gss_svc_init(); 1713 if (err) 1714 goto out_unregister; 1715 err = register_pernet_subsys(&rpcsec_gss_net_ops); 1716 if (err) 1717 goto out_svc_exit; 1718 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1719 return 0; 1720out_svc_exit: 1721 gss_svc_shutdown(); 1722out_unregister: 1723 rpcauth_unregister(&authgss_ops); 1724out: 1725 return err; 1726} 1727 1728static void __exit exit_rpcsec_gss(void) 1729{ 1730 unregister_pernet_subsys(&rpcsec_gss_net_ops); 1731 gss_svc_shutdown(); 1732 rpcauth_unregister(&authgss_ops); 1733 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1734} 1735 1736MODULE_LICENSE("GPL"); 1737module_param_named(expired_cred_retry_delay, 1738 gss_expired_cred_retry_delay, 1739 uint, 0644); 1740MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until " 1741 "the RPC engine retries an expired credential"); 1742 1743module_init(init_rpcsec_gss) 1744module_exit(exit_rpcsec_gss) 1745