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 dentry *dentry[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 inode->i_lock. 116 */ 117static void 118gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) 119{ 120 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 121 122 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 123 return; 124 gss_get_ctx(ctx); 125 rcu_assign_pointer(gss_cred->gc_ctx, ctx); 126 set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 127 smp_mb__before_clear_bit(); 128 clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags); 129} 130 131static const void * 132simple_get_bytes(const void *p, const void *end, void *res, size_t len) 133{ 134 const void *q = (const void *)((const char *)p + len); 135 if (unlikely(q > end || q < p)) 136 return ERR_PTR(-EFAULT); 137 memcpy(res, p, len); 138 return q; 139} 140 141static inline const void * 142simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) 143{ 144 const void *q; 145 unsigned int len; 146 147 p = simple_get_bytes(p, end, &len, sizeof(len)); 148 if (IS_ERR(p)) 149 return p; 150 q = (const void *)((const char *)p + len); 151 if (unlikely(q > end || q < p)) 152 return ERR_PTR(-EFAULT); 153 dest->data = kmemdup(p, len, GFP_NOFS); 154 if (unlikely(dest->data == NULL)) 155 return ERR_PTR(-ENOMEM); 156 dest->len = len; 157 return q; 158} 159 160static struct gss_cl_ctx * 161gss_cred_get_ctx(struct rpc_cred *cred) 162{ 163 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 164 struct gss_cl_ctx *ctx = NULL; 165 166 rcu_read_lock(); 167 if (gss_cred->gc_ctx) 168 ctx = gss_get_ctx(gss_cred->gc_ctx); 169 rcu_read_unlock(); 170 return ctx; 171} 172 173static struct gss_cl_ctx * 174gss_alloc_context(void) 175{ 176 struct gss_cl_ctx *ctx; 177 178 ctx = kzalloc(sizeof(*ctx), GFP_NOFS); 179 if (ctx != NULL) { 180 ctx->gc_proc = RPC_GSS_PROC_DATA; 181 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ 182 spin_lock_init(&ctx->gc_seq_lock); 183 atomic_set(&ctx->count,1); 184 } 185 return ctx; 186} 187 188#define GSSD_MIN_TIMEOUT (60 * 60) 189static const void * 190gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) 191{ 192 const void *q; 193 unsigned int seclen; 194 unsigned int timeout; 195 u32 window_size; 196 int ret; 197 198 /* First unsigned int gives the lifetime (in seconds) of the cred */ 199 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 200 if (IS_ERR(p)) 201 goto err; 202 if (timeout == 0) 203 timeout = GSSD_MIN_TIMEOUT; 204 ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4; 205 /* Sequence number window. Determines the maximum number of simultaneous requests */ 206 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 207 if (IS_ERR(p)) 208 goto err; 209 ctx->gc_win = window_size; 210 /* gssd signals an error by passing ctx->gc_win = 0: */ 211 if (ctx->gc_win == 0) { 212 /* 213 * in which case, p points to an error code. Anything other 214 * than -EKEYEXPIRED gets converted to -EACCES. 215 */ 216 p = simple_get_bytes(p, end, &ret, sizeof(ret)); 217 if (!IS_ERR(p)) 218 p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) : 219 ERR_PTR(-EACCES); 220 goto err; 221 } 222 /* copy the opaque wire context */ 223 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 224 if (IS_ERR(p)) 225 goto err; 226 /* import the opaque security context */ 227 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 228 if (IS_ERR(p)) 229 goto err; 230 q = (const void *)((const char *)p + seclen); 231 if (unlikely(q > end || q < p)) { 232 p = ERR_PTR(-EFAULT); 233 goto err; 234 } 235 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, GFP_NOFS); 236 if (ret < 0) { 237 p = ERR_PTR(ret); 238 goto err; 239 } 240 return q; 241err: 242 dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p)); 243 return p; 244} 245 246#define UPCALL_BUF_LEN 128 247 248struct gss_upcall_msg { 249 atomic_t count; 250 uid_t uid; 251 struct rpc_pipe_msg msg; 252 struct list_head list; 253 struct gss_auth *auth; 254 struct rpc_inode *inode; 255 struct rpc_wait_queue rpc_waitqueue; 256 wait_queue_head_t waitqueue; 257 struct gss_cl_ctx *ctx; 258 char databuf[UPCALL_BUF_LEN]; 259}; 260 261static int get_pipe_version(void) 262{ 263 int ret; 264 265 spin_lock(&pipe_version_lock); 266 if (pipe_version >= 0) { 267 atomic_inc(&pipe_users); 268 ret = pipe_version; 269 } else 270 ret = -EAGAIN; 271 spin_unlock(&pipe_version_lock); 272 return ret; 273} 274 275static void put_pipe_version(void) 276{ 277 if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) { 278 pipe_version = -1; 279 spin_unlock(&pipe_version_lock); 280 } 281} 282 283static void 284gss_release_msg(struct gss_upcall_msg *gss_msg) 285{ 286 if (!atomic_dec_and_test(&gss_msg->count)) 287 return; 288 put_pipe_version(); 289 BUG_ON(!list_empty(&gss_msg->list)); 290 if (gss_msg->ctx != NULL) 291 gss_put_ctx(gss_msg->ctx); 292 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue); 293 kfree(gss_msg); 294} 295 296static struct gss_upcall_msg * 297__gss_find_upcall(struct rpc_inode *rpci, uid_t uid) 298{ 299 struct gss_upcall_msg *pos; 300 list_for_each_entry(pos, &rpci->in_downcall, list) { 301 if (pos->uid != uid) 302 continue; 303 atomic_inc(&pos->count); 304 dprintk("RPC: gss_find_upcall found msg %p\n", pos); 305 return pos; 306 } 307 dprintk("RPC: gss_find_upcall found nothing\n"); 308 return NULL; 309} 310 311/* Try to add an upcall to the pipefs queue. 312 * If an upcall owned by our uid already exists, then we return a reference 313 * to that upcall instead of adding the new upcall. 314 */ 315static inline struct gss_upcall_msg * 316gss_add_msg(struct gss_upcall_msg *gss_msg) 317{ 318 struct rpc_inode *rpci = gss_msg->inode; 319 struct inode *inode = &rpci->vfs_inode; 320 struct gss_upcall_msg *old; 321 322 spin_lock(&inode->i_lock); 323 old = __gss_find_upcall(rpci, gss_msg->uid); 324 if (old == NULL) { 325 atomic_inc(&gss_msg->count); 326 list_add(&gss_msg->list, &rpci->in_downcall); 327 } else 328 gss_msg = old; 329 spin_unlock(&inode->i_lock); 330 return gss_msg; 331} 332 333static void 334__gss_unhash_msg(struct gss_upcall_msg *gss_msg) 335{ 336 list_del_init(&gss_msg->list); 337 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 338 wake_up_all(&gss_msg->waitqueue); 339 atomic_dec(&gss_msg->count); 340} 341 342static void 343gss_unhash_msg(struct gss_upcall_msg *gss_msg) 344{ 345 struct inode *inode = &gss_msg->inode->vfs_inode; 346 347 if (list_empty(&gss_msg->list)) 348 return; 349 spin_lock(&inode->i_lock); 350 if (!list_empty(&gss_msg->list)) 351 __gss_unhash_msg(gss_msg); 352 spin_unlock(&inode->i_lock); 353} 354 355static void 356gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg) 357{ 358 switch (gss_msg->msg.errno) { 359 case 0: 360 if (gss_msg->ctx == NULL) 361 break; 362 clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 363 gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx); 364 break; 365 case -EKEYEXPIRED: 366 set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags); 367 } 368 gss_cred->gc_upcall_timestamp = jiffies; 369 gss_cred->gc_upcall = NULL; 370 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 371} 372 373static void 374gss_upcall_callback(struct rpc_task *task) 375{ 376 struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred, 377 struct gss_cred, gc_base); 378 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 379 struct inode *inode = &gss_msg->inode->vfs_inode; 380 381 spin_lock(&inode->i_lock); 382 gss_handle_downcall_result(gss_cred, gss_msg); 383 spin_unlock(&inode->i_lock); 384 task->tk_status = gss_msg->msg.errno; 385 gss_release_msg(gss_msg); 386} 387 388static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 389{ 390 gss_msg->msg.data = &gss_msg->uid; 391 gss_msg->msg.len = sizeof(gss_msg->uid); 392} 393 394static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 395 struct rpc_clnt *clnt, int machine_cred) 396{ 397 struct gss_api_mech *mech = gss_msg->auth->mech; 398 char *p = gss_msg->databuf; 399 int len = 0; 400 401 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ", 402 mech->gm_name, 403 gss_msg->uid); 404 p += gss_msg->msg.len; 405 if (clnt->cl_principal) { 406 len = sprintf(p, "target=%s ", clnt->cl_principal); 407 p += len; 408 gss_msg->msg.len += len; 409 } 410 if (machine_cred) { 411 len = sprintf(p, "service=* "); 412 p += len; 413 gss_msg->msg.len += len; 414 } else if (!strcmp(clnt->cl_program->name, "nfs4_cb")) { 415 len = sprintf(p, "service=nfs "); 416 p += len; 417 gss_msg->msg.len += len; 418 } 419 if (mech->gm_upcall_enctypes) { 420 len = sprintf(p, mech->gm_upcall_enctypes); 421 p += len; 422 gss_msg->msg.len += len; 423 } 424 len = sprintf(p, "\n"); 425 gss_msg->msg.len += len; 426 427 gss_msg->msg.data = gss_msg->databuf; 428 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); 429} 430 431static void gss_encode_msg(struct gss_upcall_msg *gss_msg, 432 struct rpc_clnt *clnt, int machine_cred) 433{ 434 if (pipe_version == 0) 435 gss_encode_v0_msg(gss_msg); 436 else /* pipe_version == 1 */ 437 gss_encode_v1_msg(gss_msg, clnt, machine_cred); 438} 439 440static inline struct gss_upcall_msg * 441gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid, struct rpc_clnt *clnt, 442 int machine_cred) 443{ 444 struct gss_upcall_msg *gss_msg; 445 int vers; 446 447 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 448 if (gss_msg == NULL) 449 return ERR_PTR(-ENOMEM); 450 vers = get_pipe_version(); 451 if (vers < 0) { 452 kfree(gss_msg); 453 return ERR_PTR(vers); 454 } 455 gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode); 456 INIT_LIST_HEAD(&gss_msg->list); 457 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 458 init_waitqueue_head(&gss_msg->waitqueue); 459 atomic_set(&gss_msg->count, 1); 460 gss_msg->uid = uid; 461 gss_msg->auth = gss_auth; 462 gss_encode_msg(gss_msg, clnt, machine_cred); 463 return gss_msg; 464} 465 466static struct gss_upcall_msg * 467gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 468{ 469 struct gss_cred *gss_cred = container_of(cred, 470 struct gss_cred, gc_base); 471 struct gss_upcall_msg *gss_new, *gss_msg; 472 uid_t uid = cred->cr_uid; 473 474 gss_new = gss_alloc_msg(gss_auth, uid, clnt, gss_cred->gc_machine_cred); 475 if (IS_ERR(gss_new)) 476 return gss_new; 477 gss_msg = gss_add_msg(gss_new); 478 if (gss_msg == gss_new) { 479 struct inode *inode = &gss_new->inode->vfs_inode; 480 int res = rpc_queue_upcall(inode, &gss_new->msg); 481 if (res) { 482 gss_unhash_msg(gss_new); 483 gss_msg = ERR_PTR(res); 484 } 485 } else 486 gss_release_msg(gss_new); 487 return gss_msg; 488} 489 490static void warn_gssd(void) 491{ 492 static unsigned long ratelimit; 493 unsigned long now = jiffies; 494 495 if (time_after(now, ratelimit)) { 496 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 497 "Please check user daemon is running.\n"); 498 ratelimit = now + 15*HZ; 499 } 500} 501 502static inline int 503gss_refresh_upcall(struct rpc_task *task) 504{ 505 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 506 struct gss_auth *gss_auth = container_of(cred->cr_auth, 507 struct gss_auth, rpc_auth); 508 struct gss_cred *gss_cred = container_of(cred, 509 struct gss_cred, gc_base); 510 struct gss_upcall_msg *gss_msg; 511 struct inode *inode; 512 int err = 0; 513 514 dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid, 515 cred->cr_uid); 516 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 517 if (PTR_ERR(gss_msg) == -EAGAIN) { 518 warn_gssd(); 519 task->tk_timeout = 15*HZ; 520 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 521 return 0; 522 } 523 if (IS_ERR(gss_msg)) { 524 err = PTR_ERR(gss_msg); 525 goto out; 526 } 527 inode = &gss_msg->inode->vfs_inode; 528 spin_lock(&inode->i_lock); 529 if (gss_cred->gc_upcall != NULL) 530 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 531 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { 532 task->tk_timeout = 0; 533 gss_cred->gc_upcall = gss_msg; 534 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 535 atomic_inc(&gss_msg->count); 536 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 537 } else { 538 gss_handle_downcall_result(gss_cred, gss_msg); 539 err = gss_msg->msg.errno; 540 } 541 spin_unlock(&inode->i_lock); 542 gss_release_msg(gss_msg); 543out: 544 dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n", 545 task->tk_pid, cred->cr_uid, err); 546 return err; 547} 548 549static inline int 550gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 551{ 552 struct inode *inode; 553 struct rpc_cred *cred = &gss_cred->gc_base; 554 struct gss_upcall_msg *gss_msg; 555 DEFINE_WAIT(wait); 556 int err = 0; 557 558 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); 559retry: 560 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 561 if (PTR_ERR(gss_msg) == -EAGAIN) { 562 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 563 pipe_version >= 0, 15*HZ); 564 if (err) 565 goto out; 566 if (pipe_version < 0) 567 warn_gssd(); 568 goto retry; 569 } 570 if (IS_ERR(gss_msg)) { 571 err = PTR_ERR(gss_msg); 572 goto out; 573 } 574 inode = &gss_msg->inode->vfs_inode; 575 for (;;) { 576 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); 577 spin_lock(&inode->i_lock); 578 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 579 break; 580 } 581 spin_unlock(&inode->i_lock); 582 if (signalled()) { 583 err = -ERESTARTSYS; 584 goto out_intr; 585 } 586 schedule(); 587 } 588 if (gss_msg->ctx) 589 gss_cred_set_ctx(cred, gss_msg->ctx); 590 else 591 err = gss_msg->msg.errno; 592 spin_unlock(&inode->i_lock); 593out_intr: 594 finish_wait(&gss_msg->waitqueue, &wait); 595 gss_release_msg(gss_msg); 596out: 597 dprintk("RPC: gss_create_upcall for uid %u result %d\n", 598 cred->cr_uid, err); 599 return err; 600} 601 602static ssize_t 603gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, 604 char __user *dst, size_t buflen) 605{ 606 char *data = (char *)msg->data + msg->copied; 607 size_t mlen = min(msg->len, buflen); 608 unsigned long left; 609 610 left = copy_to_user(dst, data, mlen); 611 if (left == mlen) { 612 msg->errno = -EFAULT; 613 return -EFAULT; 614 } 615 616 mlen -= left; 617 msg->copied += mlen; 618 msg->errno = 0; 619 return mlen; 620} 621 622#define MSG_BUF_MAXSIZE 1024 623 624static ssize_t 625gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 626{ 627 const void *p, *end; 628 void *buf; 629 struct gss_upcall_msg *gss_msg; 630 struct inode *inode = filp->f_path.dentry->d_inode; 631 struct gss_cl_ctx *ctx; 632 uid_t uid; 633 ssize_t err = -EFBIG; 634 635 if (mlen > MSG_BUF_MAXSIZE) 636 goto out; 637 err = -ENOMEM; 638 buf = kmalloc(mlen, GFP_NOFS); 639 if (!buf) 640 goto out; 641 642 err = -EFAULT; 643 if (copy_from_user(buf, src, mlen)) 644 goto err; 645 646 end = (const void *)((char *)buf + mlen); 647 p = simple_get_bytes(buf, end, &uid, sizeof(uid)); 648 if (IS_ERR(p)) { 649 err = PTR_ERR(p); 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(&inode->i_lock); 661 gss_msg = __gss_find_upcall(RPC_I(inode), uid); 662 if (gss_msg == NULL) { 663 spin_unlock(&inode->i_lock); 664 goto err_put_ctx; 665 } 666 list_del_init(&gss_msg->list); 667 spin_unlock(&inode->i_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(&inode->i_lock); 696 __gss_unhash_msg(gss_msg); 697 spin_unlock(&inode->i_lock); 698 gss_release_msg(gss_msg); 699err_put_ctx: 700 gss_put_ctx(ctx); 701err: 702 kfree(buf); 703out: 704 dprintk("RPC: gss_pipe_downcall returning %Zd\n", 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_inode *rpci = RPC_I(inode); 744 struct gss_upcall_msg *gss_msg; 745 746restart: 747 spin_lock(&inode->i_lock); 748 list_for_each_entry(gss_msg, &rpci->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(&inode->i_lock); 756 gss_release_msg(gss_msg); 757 goto restart; 758 } 759 spin_unlock(&inode->i_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: gss_pipe_destroy_msg releasing msg %p\n", 771 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} 779 780/* 781 * NOTE: we have the opportunity to use different 782 * parameters based on the input flavor (which must be a pseudoflavor) 783 */ 784static struct rpc_auth * 785gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 786{ 787 struct gss_auth *gss_auth; 788 struct rpc_auth * auth; 789 int err = -ENOMEM; 790 791 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 792 793 if (!try_module_get(THIS_MODULE)) 794 return ERR_PTR(err); 795 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 796 goto out_dec; 797 gss_auth->client = clnt; 798 err = -EINVAL; 799 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 800 if (!gss_auth->mech) { 801 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 802 __func__, flavor); 803 goto err_free; 804 } 805 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 806 if (gss_auth->service == 0) 807 goto err_put_mech; 808 auth = &gss_auth->rpc_auth; 809 auth->au_cslack = GSS_CRED_SLACK >> 2; 810 auth->au_rslack = GSS_VERF_SLACK >> 2; 811 auth->au_ops = &authgss_ops; 812 auth->au_flavor = flavor; 813 atomic_set(&auth->au_count, 1); 814 kref_init(&gss_auth->kref); 815 816 /* 817 * Note: if we created the old pipe first, then someone who 818 * examined the directory at the right moment might conclude 819 * that we supported only the old pipe. So we instead create 820 * the new pipe first. 821 */ 822 gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_path.dentry, 823 "gssd", 824 clnt, &gss_upcall_ops_v1, 825 RPC_PIPE_WAIT_FOR_OPEN); 826 if (IS_ERR(gss_auth->dentry[1])) { 827 err = PTR_ERR(gss_auth->dentry[1]); 828 goto err_put_mech; 829 } 830 831 gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_path.dentry, 832 gss_auth->mech->gm_name, 833 clnt, &gss_upcall_ops_v0, 834 RPC_PIPE_WAIT_FOR_OPEN); 835 if (IS_ERR(gss_auth->dentry[0])) { 836 err = PTR_ERR(gss_auth->dentry[0]); 837 goto err_unlink_pipe_1; 838 } 839 err = rpcauth_init_credcache(auth); 840 if (err) 841 goto err_unlink_pipe_0; 842 843 return auth; 844err_unlink_pipe_0: 845 rpc_unlink(gss_auth->dentry[0]); 846err_unlink_pipe_1: 847 rpc_unlink(gss_auth->dentry[1]); 848err_put_mech: 849 gss_mech_put(gss_auth->mech); 850err_free: 851 kfree(gss_auth); 852out_dec: 853 module_put(THIS_MODULE); 854 return ERR_PTR(err); 855} 856 857static void 858gss_free(struct gss_auth *gss_auth) 859{ 860 rpc_unlink(gss_auth->dentry[1]); 861 rpc_unlink(gss_auth->dentry[0]); 862 gss_mech_put(gss_auth->mech); 863 864 kfree(gss_auth); 865 module_put(THIS_MODULE); 866} 867 868static void 869gss_free_callback(struct kref *kref) 870{ 871 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 872 873 gss_free(gss_auth); 874} 875 876static void 877gss_destroy(struct rpc_auth *auth) 878{ 879 struct gss_auth *gss_auth; 880 881 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 882 auth, auth->au_flavor); 883 884 rpcauth_destroy_credcache(auth); 885 886 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 887 kref_put(&gss_auth->kref, gss_free_callback); 888} 889 890/* 891 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 892 * to the server with the GSS control procedure field set to 893 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 894 * all RPCSEC_GSS state associated with that context. 895 */ 896static int 897gss_destroying_context(struct rpc_cred *cred) 898{ 899 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 900 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 901 struct rpc_task *task; 902 903 if (gss_cred->gc_ctx == NULL || 904 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 905 return 0; 906 907 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 908 cred->cr_ops = &gss_nullops; 909 910 /* Take a reference to ensure the cred will be destroyed either 911 * by the RPC call or by the put_rpccred() below */ 912 get_rpccred(cred); 913 914 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 915 if (!IS_ERR(task)) 916 rpc_put_task(task); 917 918 put_rpccred(cred); 919 return 1; 920} 921 922/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 923 * to create a new cred or context, so they check that things have been 924 * allocated before freeing them. */ 925static void 926gss_do_free_ctx(struct gss_cl_ctx *ctx) 927{ 928 dprintk("RPC: gss_free_ctx\n"); 929 930 gss_delete_sec_context(&ctx->gc_gss_ctx); 931 kfree(ctx->gc_wire_ctx.data); 932 kfree(ctx); 933} 934 935static void 936gss_free_ctx_callback(struct rcu_head *head) 937{ 938 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 939 gss_do_free_ctx(ctx); 940} 941 942static void 943gss_free_ctx(struct gss_cl_ctx *ctx) 944{ 945 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 946} 947 948static void 949gss_free_cred(struct gss_cred *gss_cred) 950{ 951 dprintk("RPC: gss_free_cred %p\n", gss_cred); 952 kfree(gss_cred); 953} 954 955static void 956gss_free_cred_callback(struct rcu_head *head) 957{ 958 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 959 gss_free_cred(gss_cred); 960} 961 962static void 963gss_destroy_nullcred(struct rpc_cred *cred) 964{ 965 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 966 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 967 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 968 969 rcu_assign_pointer(gss_cred->gc_ctx, NULL); 970 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 971 if (ctx) 972 gss_put_ctx(ctx); 973 kref_put(&gss_auth->kref, gss_free_callback); 974} 975 976static void 977gss_destroy_cred(struct rpc_cred *cred) 978{ 979 980 if (gss_destroying_context(cred)) 981 return; 982 gss_destroy_nullcred(cred); 983} 984 985/* 986 * Lookup RPCSEC_GSS cred for the current process 987 */ 988static struct rpc_cred * 989gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 990{ 991 return rpcauth_lookup_credcache(auth, acred, flags); 992} 993 994static struct rpc_cred * 995gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 996{ 997 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 998 struct gss_cred *cred = NULL; 999 int err = -ENOMEM; 1000 1001 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 1002 acred->uid, auth->au_flavor); 1003 1004 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 1005 goto out_err; 1006 1007 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 1008 /* 1009 * Note: in order to force a call to call_refresh(), we deliberately 1010 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 1011 */ 1012 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 1013 cred->gc_service = gss_auth->service; 1014 cred->gc_machine_cred = acred->machine_cred; 1015 kref_get(&gss_auth->kref); 1016 return &cred->gc_base; 1017 1018out_err: 1019 dprintk("RPC: gss_create_cred failed with error %d\n", err); 1020 return ERR_PTR(err); 1021} 1022 1023static int 1024gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1025{ 1026 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1027 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1028 int err; 1029 1030 do { 1031 err = gss_create_upcall(gss_auth, gss_cred); 1032 } while (err == -EAGAIN); 1033 return err; 1034} 1035 1036static int 1037gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1038{ 1039 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1040 1041 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1042 goto out; 1043 /* Don't match with creds that have expired. */ 1044 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1045 return 0; 1046 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1047 return 0; 1048out: 1049 if (acred->machine_cred != gss_cred->gc_machine_cred) 1050 return 0; 1051 return (rc->cr_uid == acred->uid); 1052} 1053 1054/* 1055* Marshal credentials. 1056* Maybe we should keep a cached credential for performance reasons. 1057*/ 1058static __be32 * 1059gss_marshal(struct rpc_task *task, __be32 *p) 1060{ 1061 struct rpc_rqst *req = task->tk_rqstp; 1062 struct rpc_cred *cred = req->rq_cred; 1063 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1064 gc_base); 1065 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1066 __be32 *cred_len; 1067 u32 maj_stat = 0; 1068 struct xdr_netobj mic; 1069 struct kvec iov; 1070 struct xdr_buf verf_buf; 1071 1072 dprintk("RPC: %5u gss_marshal\n", task->tk_pid); 1073 1074 *p++ = htonl(RPC_AUTH_GSS); 1075 cred_len = p++; 1076 1077 spin_lock(&ctx->gc_seq_lock); 1078 req->rq_seqno = ctx->gc_seq++; 1079 spin_unlock(&ctx->gc_seq_lock); 1080 1081 *p++ = htonl((u32) RPC_GSS_VERSION); 1082 *p++ = htonl((u32) ctx->gc_proc); 1083 *p++ = htonl((u32) req->rq_seqno); 1084 *p++ = htonl((u32) gss_cred->gc_service); 1085 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1086 *cred_len = htonl((p - (cred_len + 1)) << 2); 1087 1088 /* We compute the checksum for the verifier over the xdr-encoded bytes 1089 * starting with the xid and ending at the end of the credential: */ 1090 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 1091 req->rq_snd_buf.head[0].iov_base); 1092 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1093 xdr_buf_from_iov(&iov, &verf_buf); 1094 1095 /* set verifier flavor*/ 1096 *p++ = htonl(RPC_AUTH_GSS); 1097 1098 mic.data = (u8 *)(p + 1); 1099 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1100 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1101 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1102 } else if (maj_stat != 0) { 1103 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1104 goto out_put_ctx; 1105 } 1106 p = xdr_encode_opaque(p, NULL, mic.len); 1107 gss_put_ctx(ctx); 1108 return p; 1109out_put_ctx: 1110 gss_put_ctx(ctx); 1111 return NULL; 1112} 1113 1114static int gss_renew_cred(struct rpc_task *task) 1115{ 1116 struct rpc_cred *oldcred = task->tk_rqstp->rq_cred; 1117 struct gss_cred *gss_cred = container_of(oldcred, 1118 struct gss_cred, 1119 gc_base); 1120 struct rpc_auth *auth = oldcred->cr_auth; 1121 struct auth_cred acred = { 1122 .uid = oldcred->cr_uid, 1123 .machine_cred = gss_cred->gc_machine_cred, 1124 }; 1125 struct rpc_cred *new; 1126 1127 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1128 if (IS_ERR(new)) 1129 return PTR_ERR(new); 1130 task->tk_rqstp->rq_cred = new; 1131 put_rpccred(oldcred); 1132 return 0; 1133} 1134 1135static int gss_cred_is_negative_entry(struct rpc_cred *cred) 1136{ 1137 if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) { 1138 unsigned long now = jiffies; 1139 unsigned long begin, expire; 1140 struct gss_cred *gss_cred; 1141 1142 gss_cred = container_of(cred, struct gss_cred, gc_base); 1143 begin = gss_cred->gc_upcall_timestamp; 1144 expire = begin + gss_expired_cred_retry_delay * HZ; 1145 1146 if (time_in_range_open(now, begin, expire)) 1147 return 1; 1148 } 1149 return 0; 1150} 1151 1152static int 1153gss_refresh(struct rpc_task *task) 1154{ 1155 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1156 int ret = 0; 1157 1158 if (gss_cred_is_negative_entry(cred)) 1159 return -EKEYEXPIRED; 1160 1161 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1162 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1163 ret = gss_renew_cred(task); 1164 if (ret < 0) 1165 goto out; 1166 cred = task->tk_rqstp->rq_cred; 1167 } 1168 1169 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1170 ret = gss_refresh_upcall(task); 1171out: 1172 return ret; 1173} 1174 1175/* Dummy refresh routine: used only when destroying the context */ 1176static int 1177gss_refresh_null(struct rpc_task *task) 1178{ 1179 return -EACCES; 1180} 1181 1182static __be32 * 1183gss_validate(struct rpc_task *task, __be32 *p) 1184{ 1185 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1186 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1187 __be32 seq; 1188 struct kvec iov; 1189 struct xdr_buf verf_buf; 1190 struct xdr_netobj mic; 1191 u32 flav,len; 1192 u32 maj_stat; 1193 1194 dprintk("RPC: %5u gss_validate\n", task->tk_pid); 1195 1196 flav = ntohl(*p++); 1197 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1198 goto out_bad; 1199 if (flav != RPC_AUTH_GSS) 1200 goto out_bad; 1201 seq = htonl(task->tk_rqstp->rq_seqno); 1202 iov.iov_base = &seq; 1203 iov.iov_len = sizeof(seq); 1204 xdr_buf_from_iov(&iov, &verf_buf); 1205 mic.data = (u8 *)p; 1206 mic.len = len; 1207 1208 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1209 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1210 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1211 if (maj_stat) { 1212 dprintk("RPC: %5u gss_validate: gss_verify_mic returned " 1213 "error 0x%08x\n", task->tk_pid, maj_stat); 1214 goto out_bad; 1215 } 1216 /* We leave it to unwrap to calculate au_rslack. For now we just 1217 * calculate the length of the verifier: */ 1218 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1219 gss_put_ctx(ctx); 1220 dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n", 1221 task->tk_pid); 1222 return p + XDR_QUADLEN(len); 1223out_bad: 1224 gss_put_ctx(ctx); 1225 dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid); 1226 return NULL; 1227} 1228 1229static inline int 1230gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1231 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1232{ 1233 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1234 struct xdr_buf integ_buf; 1235 __be32 *integ_len = NULL; 1236 struct xdr_netobj mic; 1237 u32 offset; 1238 __be32 *q; 1239 struct kvec *iov; 1240 u32 maj_stat = 0; 1241 int status = -EIO; 1242 1243 integ_len = p++; 1244 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1245 *p++ = htonl(rqstp->rq_seqno); 1246 1247 status = encode(rqstp, p, obj); 1248 if (status) 1249 return status; 1250 1251 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1252 offset, snd_buf->len - offset)) 1253 return status; 1254 *integ_len = htonl(integ_buf.len); 1255 1256 /* guess whether we're in the head or the tail: */ 1257 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1258 iov = snd_buf->tail; 1259 else 1260 iov = snd_buf->head; 1261 p = iov->iov_base + iov->iov_len; 1262 mic.data = (u8 *)(p + 1); 1263 1264 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1265 status = -EIO; 1266 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1267 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1268 else if (maj_stat) 1269 return status; 1270 q = xdr_encode_opaque(p, NULL, mic.len); 1271 1272 offset = (u8 *)q - (u8 *)p; 1273 iov->iov_len += offset; 1274 snd_buf->len += offset; 1275 return 0; 1276} 1277 1278static void 1279priv_release_snd_buf(struct rpc_rqst *rqstp) 1280{ 1281 int i; 1282 1283 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1284 __free_page(rqstp->rq_enc_pages[i]); 1285 kfree(rqstp->rq_enc_pages); 1286} 1287 1288static int 1289alloc_enc_pages(struct rpc_rqst *rqstp) 1290{ 1291 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1292 int first, last, i; 1293 1294 if (snd_buf->page_len == 0) { 1295 rqstp->rq_enc_pages_num = 0; 1296 return 0; 1297 } 1298 1299 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1300 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1301 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1302 rqstp->rq_enc_pages 1303 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1304 GFP_NOFS); 1305 if (!rqstp->rq_enc_pages) 1306 goto out; 1307 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1308 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1309 if (rqstp->rq_enc_pages[i] == NULL) 1310 goto out_free; 1311 } 1312 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1313 return 0; 1314out_free: 1315 rqstp->rq_enc_pages_num = i; 1316 priv_release_snd_buf(rqstp); 1317out: 1318 return -EAGAIN; 1319} 1320 1321static inline int 1322gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1323 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1324{ 1325 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1326 u32 offset; 1327 u32 maj_stat; 1328 int status; 1329 __be32 *opaque_len; 1330 struct page **inpages; 1331 int first; 1332 int pad; 1333 struct kvec *iov; 1334 char *tmp; 1335 1336 opaque_len = p++; 1337 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1338 *p++ = htonl(rqstp->rq_seqno); 1339 1340 status = encode(rqstp, p, obj); 1341 if (status) 1342 return status; 1343 1344 status = alloc_enc_pages(rqstp); 1345 if (status) 1346 return status; 1347 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1348 inpages = snd_buf->pages + first; 1349 snd_buf->pages = rqstp->rq_enc_pages; 1350 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1351 /* 1352 * Give the tail its own page, in case we need extra space in the 1353 * head when wrapping: 1354 * 1355 * call_allocate() allocates twice the slack space required 1356 * by the authentication flavor to rq_callsize. 1357 * For GSS, slack is GSS_CRED_SLACK. 1358 */ 1359 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1360 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1361 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1362 snd_buf->tail[0].iov_base = tmp; 1363 } 1364 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1365 /* slack space should prevent this ever happening: */ 1366 BUG_ON(snd_buf->len > snd_buf->buflen); 1367 status = -EIO; 1368 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1369 * done anyway, so it's safe to put the request on the wire: */ 1370 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1371 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1372 else if (maj_stat) 1373 return status; 1374 1375 *opaque_len = htonl(snd_buf->len - offset); 1376 /* guess whether we're in the head or the tail: */ 1377 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1378 iov = snd_buf->tail; 1379 else 1380 iov = snd_buf->head; 1381 p = iov->iov_base + iov->iov_len; 1382 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1383 memset(p, 0, pad); 1384 iov->iov_len += pad; 1385 snd_buf->len += pad; 1386 1387 return 0; 1388} 1389 1390static int 1391gss_wrap_req(struct rpc_task *task, 1392 kxdrproc_t encode, void *rqstp, __be32 *p, void *obj) 1393{ 1394 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1395 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1396 gc_base); 1397 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1398 int status = -EIO; 1399 1400 dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid); 1401 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1402 /* The spec seems a little ambiguous here, but I think that not 1403 * wrapping context destruction requests makes the most sense. 1404 */ 1405 status = encode(rqstp, p, obj); 1406 goto out; 1407 } 1408 switch (gss_cred->gc_service) { 1409 case RPC_GSS_SVC_NONE: 1410 status = encode(rqstp, p, obj); 1411 break; 1412 case RPC_GSS_SVC_INTEGRITY: 1413 status = gss_wrap_req_integ(cred, ctx, encode, 1414 rqstp, p, obj); 1415 break; 1416 case RPC_GSS_SVC_PRIVACY: 1417 status = gss_wrap_req_priv(cred, ctx, encode, 1418 rqstp, p, obj); 1419 break; 1420 } 1421out: 1422 gss_put_ctx(ctx); 1423 dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status); 1424 return status; 1425} 1426 1427static inline int 1428gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1429 struct rpc_rqst *rqstp, __be32 **p) 1430{ 1431 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1432 struct xdr_buf integ_buf; 1433 struct xdr_netobj mic; 1434 u32 data_offset, mic_offset; 1435 u32 integ_len; 1436 u32 maj_stat; 1437 int status = -EIO; 1438 1439 integ_len = ntohl(*(*p)++); 1440 if (integ_len & 3) 1441 return status; 1442 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1443 mic_offset = integ_len + data_offset; 1444 if (mic_offset > rcv_buf->len) 1445 return status; 1446 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1447 return status; 1448 1449 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1450 mic_offset - data_offset)) 1451 return status; 1452 1453 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1454 return status; 1455 1456 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1457 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1458 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1459 if (maj_stat != GSS_S_COMPLETE) 1460 return status; 1461 return 0; 1462} 1463 1464static inline int 1465gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1466 struct rpc_rqst *rqstp, __be32 **p) 1467{ 1468 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1469 u32 offset; 1470 u32 opaque_len; 1471 u32 maj_stat; 1472 int status = -EIO; 1473 1474 opaque_len = ntohl(*(*p)++); 1475 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1476 if (offset + opaque_len > rcv_buf->len) 1477 return status; 1478 /* remove padding: */ 1479 rcv_buf->len = offset + opaque_len; 1480 1481 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1482 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1483 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1484 if (maj_stat != GSS_S_COMPLETE) 1485 return status; 1486 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1487 return status; 1488 1489 return 0; 1490} 1491 1492 1493static int 1494gss_unwrap_resp(struct rpc_task *task, 1495 kxdrproc_t decode, void *rqstp, __be32 *p, void *obj) 1496{ 1497 struct rpc_cred *cred = task->tk_rqstp->rq_cred; 1498 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1499 gc_base); 1500 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1501 __be32 *savedp = p; 1502 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1503 int savedlen = head->iov_len; 1504 int status = -EIO; 1505 1506 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1507 goto out_decode; 1508 switch (gss_cred->gc_service) { 1509 case RPC_GSS_SVC_NONE: 1510 break; 1511 case RPC_GSS_SVC_INTEGRITY: 1512 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1513 if (status) 1514 goto out; 1515 break; 1516 case RPC_GSS_SVC_PRIVACY: 1517 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1518 if (status) 1519 goto out; 1520 break; 1521 } 1522 /* take into account extra slack for integrity and privacy cases: */ 1523 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1524 + (savedlen - head->iov_len); 1525out_decode: 1526 status = decode(rqstp, p, obj); 1527out: 1528 gss_put_ctx(ctx); 1529 dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid, 1530 status); 1531 return status; 1532} 1533 1534static const struct rpc_authops authgss_ops = { 1535 .owner = THIS_MODULE, 1536 .au_flavor = RPC_AUTH_GSS, 1537 .au_name = "RPCSEC_GSS", 1538 .create = gss_create, 1539 .destroy = gss_destroy, 1540 .lookup_cred = gss_lookup_cred, 1541 .crcreate = gss_create_cred 1542}; 1543 1544static const struct rpc_credops gss_credops = { 1545 .cr_name = "AUTH_GSS", 1546 .crdestroy = gss_destroy_cred, 1547 .cr_init = gss_cred_init, 1548 .crbind = rpcauth_generic_bind_cred, 1549 .crmatch = gss_match, 1550 .crmarshal = gss_marshal, 1551 .crrefresh = gss_refresh, 1552 .crvalidate = gss_validate, 1553 .crwrap_req = gss_wrap_req, 1554 .crunwrap_resp = gss_unwrap_resp, 1555}; 1556 1557static const struct rpc_credops gss_nullops = { 1558 .cr_name = "AUTH_GSS", 1559 .crdestroy = gss_destroy_nullcred, 1560 .crbind = rpcauth_generic_bind_cred, 1561 .crmatch = gss_match, 1562 .crmarshal = gss_marshal, 1563 .crrefresh = gss_refresh_null, 1564 .crvalidate = gss_validate, 1565 .crwrap_req = gss_wrap_req, 1566 .crunwrap_resp = gss_unwrap_resp, 1567}; 1568 1569static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 1570 .upcall = gss_pipe_upcall, 1571 .downcall = gss_pipe_downcall, 1572 .destroy_msg = gss_pipe_destroy_msg, 1573 .open_pipe = gss_pipe_open_v0, 1574 .release_pipe = gss_pipe_release, 1575}; 1576 1577static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 1578 .upcall = gss_pipe_upcall, 1579 .downcall = gss_pipe_downcall, 1580 .destroy_msg = gss_pipe_destroy_msg, 1581 .open_pipe = gss_pipe_open_v1, 1582 .release_pipe = gss_pipe_release, 1583}; 1584 1585/* 1586 * Initialize RPCSEC_GSS module 1587 */ 1588static int __init init_rpcsec_gss(void) 1589{ 1590 int err = 0; 1591 1592 err = rpcauth_register(&authgss_ops); 1593 if (err) 1594 goto out; 1595 err = gss_svc_init(); 1596 if (err) 1597 goto out_unregister; 1598 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1599 return 0; 1600out_unregister: 1601 rpcauth_unregister(&authgss_ops); 1602out: 1603 return err; 1604} 1605 1606static void __exit exit_rpcsec_gss(void) 1607{ 1608 gss_svc_shutdown(); 1609 rpcauth_unregister(&authgss_ops); 1610 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1611} 1612 1613MODULE_LICENSE("GPL"); 1614module_param_named(expired_cred_retry_delay, 1615 gss_expired_cred_retry_delay, 1616 uint, 0644); 1617MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until " 1618 "the RPC engine retries an expired credential"); 1619 1620module_init(init_rpcsec_gss) 1621module_exit(exit_rpcsec_gss) 1622