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 55 static const struct rpc_authops authgss_ops; 56 57 static const struct rpc_credops gss_credops; 58 static const struct rpc_credops gss_nullops; 59 60 #ifdef RPC_DEBUG 61 # define RPCDBG_FACILITY RPCDBG_AUTH 62 #endif 63 64 #define GSS_CRED_SLACK 1024 65 /* length of a krb5 verifier (48), plus data added before arguments when 66 * using integrity (two 4-byte integers): */ 67 #define GSS_VERF_SLACK 100 68 69 struct gss_auth { 70 struct kref kref; 71 struct rpc_auth rpc_auth; 72 struct gss_api_mech *mech; 73 enum rpc_gss_svc service; 74 struct rpc_clnt *client; 75 /* 76 * There are two upcall pipes; dentry[1], named "gssd", is used 77 * for the new text-based upcall; dentry[0] is named after the 78 * mechanism (for example, "krb5") and exists for 79 * backwards-compatibility with older gssd's. 80 */ 81 struct dentry *dentry[2]; 82 }; 83 84 /* pipe_version >= 0 if and only if someone has a pipe open. */ 85 static int pipe_version = -1; 86 static atomic_t pipe_users = ATOMIC_INIT(0); 87 static DEFINE_SPINLOCK(pipe_version_lock); 88 static struct rpc_wait_queue pipe_version_rpc_waitqueue; 89 static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue); 90 91 static void gss_free_ctx(struct gss_cl_ctx *); 92 static struct rpc_pipe_ops gss_upcall_ops_v0; 93 static struct rpc_pipe_ops gss_upcall_ops_v1; 94 95 static inline struct gss_cl_ctx * 96 gss_get_ctx(struct gss_cl_ctx *ctx) 97 { 98 atomic_inc(&ctx->count); 99 return ctx; 100 } 101 102 static inline void 103 gss_put_ctx(struct gss_cl_ctx *ctx) 104 { 105 if (atomic_dec_and_test(&ctx->count)) 106 gss_free_ctx(ctx); 107 } 108 109 /* gss_cred_set_ctx: 110 * called by gss_upcall_callback and gss_create_upcall in order 111 * to set the gss context. The actual exchange of an old context 112 * and a new one is protected by the inode->i_lock. 113 */ 114 static void 115 gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) 116 { 117 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 118 119 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 120 return; 121 gss_get_ctx(ctx); 122 rcu_assign_pointer(gss_cred->gc_ctx, ctx); 123 set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 124 smp_mb__before_clear_bit(); 125 clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags); 126 } 127 128 static const void * 129 simple_get_bytes(const void *p, const void *end, void *res, size_t len) 130 { 131 const void *q = (const void *)((const char *)p + len); 132 if (unlikely(q > end || q < p)) 133 return ERR_PTR(-EFAULT); 134 memcpy(res, p, len); 135 return q; 136 } 137 138 static inline const void * 139 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) 140 { 141 const void *q; 142 unsigned int len; 143 144 p = simple_get_bytes(p, end, &len, sizeof(len)); 145 if (IS_ERR(p)) 146 return p; 147 q = (const void *)((const char *)p + len); 148 if (unlikely(q > end || q < p)) 149 return ERR_PTR(-EFAULT); 150 dest->data = kmemdup(p, len, GFP_NOFS); 151 if (unlikely(dest->data == NULL)) 152 return ERR_PTR(-ENOMEM); 153 dest->len = len; 154 return q; 155 } 156 157 static struct gss_cl_ctx * 158 gss_cred_get_ctx(struct rpc_cred *cred) 159 { 160 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 161 struct gss_cl_ctx *ctx = NULL; 162 163 rcu_read_lock(); 164 if (gss_cred->gc_ctx) 165 ctx = gss_get_ctx(gss_cred->gc_ctx); 166 rcu_read_unlock(); 167 return ctx; 168 } 169 170 static struct gss_cl_ctx * 171 gss_alloc_context(void) 172 { 173 struct gss_cl_ctx *ctx; 174 175 ctx = kzalloc(sizeof(*ctx), GFP_NOFS); 176 if (ctx != NULL) { 177 ctx->gc_proc = RPC_GSS_PROC_DATA; 178 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ 179 spin_lock_init(&ctx->gc_seq_lock); 180 atomic_set(&ctx->count,1); 181 } 182 return ctx; 183 } 184 185 #define GSSD_MIN_TIMEOUT (60 * 60) 186 static const void * 187 gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) 188 { 189 const void *q; 190 unsigned int seclen; 191 unsigned int timeout; 192 u32 window_size; 193 int ret; 194 195 /* First unsigned int gives the lifetime (in seconds) of the cred */ 196 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 197 if (IS_ERR(p)) 198 goto err; 199 if (timeout == 0) 200 timeout = GSSD_MIN_TIMEOUT; 201 ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4; 202 /* Sequence number window. Determines the maximum number of simultaneous requests */ 203 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 204 if (IS_ERR(p)) 205 goto err; 206 ctx->gc_win = window_size; 207 /* gssd signals an error by passing ctx->gc_win = 0: */ 208 if (ctx->gc_win == 0) { 209 /* in which case, p points to an error code which we ignore */ 210 p = ERR_PTR(-EACCES); 211 goto err; 212 } 213 /* copy the opaque wire context */ 214 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 215 if (IS_ERR(p)) 216 goto err; 217 /* import the opaque security context */ 218 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 219 if (IS_ERR(p)) 220 goto err; 221 q = (const void *)((const char *)p + seclen); 222 if (unlikely(q > end || q < p)) { 223 p = ERR_PTR(-EFAULT); 224 goto err; 225 } 226 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx); 227 if (ret < 0) { 228 p = ERR_PTR(ret); 229 goto err; 230 } 231 return q; 232 err: 233 dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p)); 234 return p; 235 } 236 237 #define UPCALL_BUF_LEN 128 238 239 struct gss_upcall_msg { 240 atomic_t count; 241 uid_t uid; 242 struct rpc_pipe_msg msg; 243 struct list_head list; 244 struct gss_auth *auth; 245 struct rpc_inode *inode; 246 struct rpc_wait_queue rpc_waitqueue; 247 wait_queue_head_t waitqueue; 248 struct gss_cl_ctx *ctx; 249 char databuf[UPCALL_BUF_LEN]; 250 }; 251 252 static int get_pipe_version(void) 253 { 254 int ret; 255 256 spin_lock(&pipe_version_lock); 257 if (pipe_version >= 0) { 258 atomic_inc(&pipe_users); 259 ret = pipe_version; 260 } else 261 ret = -EAGAIN; 262 spin_unlock(&pipe_version_lock); 263 return ret; 264 } 265 266 static void put_pipe_version(void) 267 { 268 if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) { 269 pipe_version = -1; 270 spin_unlock(&pipe_version_lock); 271 } 272 } 273 274 static void 275 gss_release_msg(struct gss_upcall_msg *gss_msg) 276 { 277 if (!atomic_dec_and_test(&gss_msg->count)) 278 return; 279 put_pipe_version(); 280 BUG_ON(!list_empty(&gss_msg->list)); 281 if (gss_msg->ctx != NULL) 282 gss_put_ctx(gss_msg->ctx); 283 rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue); 284 kfree(gss_msg); 285 } 286 287 static struct gss_upcall_msg * 288 __gss_find_upcall(struct rpc_inode *rpci, uid_t uid) 289 { 290 struct gss_upcall_msg *pos; 291 list_for_each_entry(pos, &rpci->in_downcall, list) { 292 if (pos->uid != uid) 293 continue; 294 atomic_inc(&pos->count); 295 dprintk("RPC: gss_find_upcall found msg %p\n", pos); 296 return pos; 297 } 298 dprintk("RPC: gss_find_upcall found nothing\n"); 299 return NULL; 300 } 301 302 /* Try to add an upcall to the pipefs queue. 303 * If an upcall owned by our uid already exists, then we return a reference 304 * to that upcall instead of adding the new upcall. 305 */ 306 static inline struct gss_upcall_msg * 307 gss_add_msg(struct gss_auth *gss_auth, struct gss_upcall_msg *gss_msg) 308 { 309 struct rpc_inode *rpci = gss_msg->inode; 310 struct inode *inode = &rpci->vfs_inode; 311 struct gss_upcall_msg *old; 312 313 spin_lock(&inode->i_lock); 314 old = __gss_find_upcall(rpci, gss_msg->uid); 315 if (old == NULL) { 316 atomic_inc(&gss_msg->count); 317 list_add(&gss_msg->list, &rpci->in_downcall); 318 } else 319 gss_msg = old; 320 spin_unlock(&inode->i_lock); 321 return gss_msg; 322 } 323 324 static void 325 __gss_unhash_msg(struct gss_upcall_msg *gss_msg) 326 { 327 list_del_init(&gss_msg->list); 328 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 329 wake_up_all(&gss_msg->waitqueue); 330 atomic_dec(&gss_msg->count); 331 } 332 333 static void 334 gss_unhash_msg(struct gss_upcall_msg *gss_msg) 335 { 336 struct inode *inode = &gss_msg->inode->vfs_inode; 337 338 if (list_empty(&gss_msg->list)) 339 return; 340 spin_lock(&inode->i_lock); 341 if (!list_empty(&gss_msg->list)) 342 __gss_unhash_msg(gss_msg); 343 spin_unlock(&inode->i_lock); 344 } 345 346 static void 347 gss_upcall_callback(struct rpc_task *task) 348 { 349 struct gss_cred *gss_cred = container_of(task->tk_msg.rpc_cred, 350 struct gss_cred, gc_base); 351 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 352 struct inode *inode = &gss_msg->inode->vfs_inode; 353 354 spin_lock(&inode->i_lock); 355 if (gss_msg->ctx) 356 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_msg->ctx); 357 else 358 task->tk_status = gss_msg->msg.errno; 359 gss_cred->gc_upcall = NULL; 360 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 361 spin_unlock(&inode->i_lock); 362 gss_release_msg(gss_msg); 363 } 364 365 static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg) 366 { 367 gss_msg->msg.data = &gss_msg->uid; 368 gss_msg->msg.len = sizeof(gss_msg->uid); 369 } 370 371 static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, 372 struct rpc_clnt *clnt, int machine_cred) 373 { 374 char *p = gss_msg->databuf; 375 int len = 0; 376 377 gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ", 378 gss_msg->auth->mech->gm_name, 379 gss_msg->uid); 380 p += gss_msg->msg.len; 381 if (clnt->cl_principal) { 382 len = sprintf(p, "target=%s ", clnt->cl_principal); 383 p += len; 384 gss_msg->msg.len += len; 385 } 386 if (machine_cred) { 387 len = sprintf(p, "service=* "); 388 p += len; 389 gss_msg->msg.len += len; 390 } else if (!strcmp(clnt->cl_program->name, "nfs4_cb")) { 391 len = sprintf(p, "service=nfs "); 392 p += len; 393 gss_msg->msg.len += len; 394 } 395 len = sprintf(p, "\n"); 396 gss_msg->msg.len += len; 397 398 gss_msg->msg.data = gss_msg->databuf; 399 BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN); 400 } 401 402 static void gss_encode_msg(struct gss_upcall_msg *gss_msg, 403 struct rpc_clnt *clnt, int machine_cred) 404 { 405 if (pipe_version == 0) 406 gss_encode_v0_msg(gss_msg); 407 else /* pipe_version == 1 */ 408 gss_encode_v1_msg(gss_msg, clnt, machine_cred); 409 } 410 411 static inline struct gss_upcall_msg * 412 gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid, struct rpc_clnt *clnt, 413 int machine_cred) 414 { 415 struct gss_upcall_msg *gss_msg; 416 int vers; 417 418 gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS); 419 if (gss_msg == NULL) 420 return ERR_PTR(-ENOMEM); 421 vers = get_pipe_version(); 422 if (vers < 0) { 423 kfree(gss_msg); 424 return ERR_PTR(vers); 425 } 426 gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode); 427 INIT_LIST_HEAD(&gss_msg->list); 428 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 429 init_waitqueue_head(&gss_msg->waitqueue); 430 atomic_set(&gss_msg->count, 1); 431 gss_msg->uid = uid; 432 gss_msg->auth = gss_auth; 433 gss_encode_msg(gss_msg, clnt, machine_cred); 434 return gss_msg; 435 } 436 437 static struct gss_upcall_msg * 438 gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 439 { 440 struct gss_cred *gss_cred = container_of(cred, 441 struct gss_cred, gc_base); 442 struct gss_upcall_msg *gss_new, *gss_msg; 443 uid_t uid = cred->cr_uid; 444 445 gss_new = gss_alloc_msg(gss_auth, uid, clnt, gss_cred->gc_machine_cred); 446 if (IS_ERR(gss_new)) 447 return gss_new; 448 gss_msg = gss_add_msg(gss_auth, gss_new); 449 if (gss_msg == gss_new) { 450 struct inode *inode = &gss_new->inode->vfs_inode; 451 int res = rpc_queue_upcall(inode, &gss_new->msg); 452 if (res) { 453 gss_unhash_msg(gss_new); 454 gss_msg = ERR_PTR(res); 455 } 456 } else 457 gss_release_msg(gss_new); 458 return gss_msg; 459 } 460 461 static void warn_gssd(void) 462 { 463 static unsigned long ratelimit; 464 unsigned long now = jiffies; 465 466 if (time_after(now, ratelimit)) { 467 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 468 "Please check user daemon is running.\n"); 469 ratelimit = now + 15*HZ; 470 } 471 } 472 473 static inline int 474 gss_refresh_upcall(struct rpc_task *task) 475 { 476 struct rpc_cred *cred = task->tk_msg.rpc_cred; 477 struct gss_auth *gss_auth = container_of(cred->cr_auth, 478 struct gss_auth, rpc_auth); 479 struct gss_cred *gss_cred = container_of(cred, 480 struct gss_cred, gc_base); 481 struct gss_upcall_msg *gss_msg; 482 struct inode *inode; 483 int err = 0; 484 485 dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid, 486 cred->cr_uid); 487 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 488 if (IS_ERR(gss_msg) == -EAGAIN) { 489 /* XXX: warning on the first, under the assumption we 490 * shouldn't normally hit this case on a refresh. */ 491 warn_gssd(); 492 task->tk_timeout = 15*HZ; 493 rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL); 494 return 0; 495 } 496 if (IS_ERR(gss_msg)) { 497 err = PTR_ERR(gss_msg); 498 goto out; 499 } 500 inode = &gss_msg->inode->vfs_inode; 501 spin_lock(&inode->i_lock); 502 if (gss_cred->gc_upcall != NULL) 503 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL); 504 else if (gss_msg->ctx != NULL) { 505 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_msg->ctx); 506 gss_cred->gc_upcall = NULL; 507 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 508 } else if (gss_msg->msg.errno >= 0) { 509 task->tk_timeout = 0; 510 gss_cred->gc_upcall = gss_msg; 511 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 512 atomic_inc(&gss_msg->count); 513 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback); 514 } else 515 err = gss_msg->msg.errno; 516 spin_unlock(&inode->i_lock); 517 gss_release_msg(gss_msg); 518 out: 519 dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n", 520 task->tk_pid, cred->cr_uid, err); 521 return err; 522 } 523 524 static inline int 525 gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 526 { 527 struct inode *inode; 528 struct rpc_cred *cred = &gss_cred->gc_base; 529 struct gss_upcall_msg *gss_msg; 530 DEFINE_WAIT(wait); 531 int err = 0; 532 533 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); 534 retry: 535 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 536 if (PTR_ERR(gss_msg) == -EAGAIN) { 537 err = wait_event_interruptible_timeout(pipe_version_waitqueue, 538 pipe_version >= 0, 15*HZ); 539 if (err) 540 goto out; 541 if (pipe_version < 0) 542 warn_gssd(); 543 goto retry; 544 } 545 if (IS_ERR(gss_msg)) { 546 err = PTR_ERR(gss_msg); 547 goto out; 548 } 549 inode = &gss_msg->inode->vfs_inode; 550 for (;;) { 551 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); 552 spin_lock(&inode->i_lock); 553 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 554 break; 555 } 556 spin_unlock(&inode->i_lock); 557 if (signalled()) { 558 err = -ERESTARTSYS; 559 goto out_intr; 560 } 561 schedule(); 562 } 563 if (gss_msg->ctx) 564 gss_cred_set_ctx(cred, gss_msg->ctx); 565 else 566 err = gss_msg->msg.errno; 567 spin_unlock(&inode->i_lock); 568 out_intr: 569 finish_wait(&gss_msg->waitqueue, &wait); 570 gss_release_msg(gss_msg); 571 out: 572 dprintk("RPC: gss_create_upcall for uid %u result %d\n", 573 cred->cr_uid, err); 574 return err; 575 } 576 577 static ssize_t 578 gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, 579 char __user *dst, size_t buflen) 580 { 581 char *data = (char *)msg->data + msg->copied; 582 size_t mlen = min(msg->len, buflen); 583 unsigned long left; 584 585 left = copy_to_user(dst, data, mlen); 586 if (left == mlen) { 587 msg->errno = -EFAULT; 588 return -EFAULT; 589 } 590 591 mlen -= left; 592 msg->copied += mlen; 593 msg->errno = 0; 594 return mlen; 595 } 596 597 #define MSG_BUF_MAXSIZE 1024 598 599 static ssize_t 600 gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 601 { 602 const void *p, *end; 603 void *buf; 604 struct gss_upcall_msg *gss_msg; 605 struct inode *inode = filp->f_path.dentry->d_inode; 606 struct gss_cl_ctx *ctx; 607 uid_t uid; 608 ssize_t err = -EFBIG; 609 610 if (mlen > MSG_BUF_MAXSIZE) 611 goto out; 612 err = -ENOMEM; 613 buf = kmalloc(mlen, GFP_NOFS); 614 if (!buf) 615 goto out; 616 617 err = -EFAULT; 618 if (copy_from_user(buf, src, mlen)) 619 goto err; 620 621 end = (const void *)((char *)buf + mlen); 622 p = simple_get_bytes(buf, end, &uid, sizeof(uid)); 623 if (IS_ERR(p)) { 624 err = PTR_ERR(p); 625 goto err; 626 } 627 628 err = -ENOMEM; 629 ctx = gss_alloc_context(); 630 if (ctx == NULL) 631 goto err; 632 633 err = -ENOENT; 634 /* Find a matching upcall */ 635 spin_lock(&inode->i_lock); 636 gss_msg = __gss_find_upcall(RPC_I(inode), uid); 637 if (gss_msg == NULL) { 638 spin_unlock(&inode->i_lock); 639 goto err_put_ctx; 640 } 641 list_del_init(&gss_msg->list); 642 spin_unlock(&inode->i_lock); 643 644 p = gss_fill_context(p, end, ctx, gss_msg->auth->mech); 645 if (IS_ERR(p)) { 646 err = PTR_ERR(p); 647 gss_msg->msg.errno = (err == -EAGAIN) ? -EAGAIN : -EACCES; 648 goto err_release_msg; 649 } 650 gss_msg->ctx = gss_get_ctx(ctx); 651 err = mlen; 652 653 err_release_msg: 654 spin_lock(&inode->i_lock); 655 __gss_unhash_msg(gss_msg); 656 spin_unlock(&inode->i_lock); 657 gss_release_msg(gss_msg); 658 err_put_ctx: 659 gss_put_ctx(ctx); 660 err: 661 kfree(buf); 662 out: 663 dprintk("RPC: gss_pipe_downcall returning %Zd\n", err); 664 return err; 665 } 666 667 static int gss_pipe_open(struct inode *inode, int new_version) 668 { 669 int ret = 0; 670 671 spin_lock(&pipe_version_lock); 672 if (pipe_version < 0) { 673 /* First open of any gss pipe determines the version: */ 674 pipe_version = new_version; 675 rpc_wake_up(&pipe_version_rpc_waitqueue); 676 wake_up(&pipe_version_waitqueue); 677 } else if (pipe_version != new_version) { 678 /* Trying to open a pipe of a different version */ 679 ret = -EBUSY; 680 goto out; 681 } 682 atomic_inc(&pipe_users); 683 out: 684 spin_unlock(&pipe_version_lock); 685 return ret; 686 687 } 688 689 static int gss_pipe_open_v0(struct inode *inode) 690 { 691 return gss_pipe_open(inode, 0); 692 } 693 694 static int gss_pipe_open_v1(struct inode *inode) 695 { 696 return gss_pipe_open(inode, 1); 697 } 698 699 static void 700 gss_pipe_release(struct inode *inode) 701 { 702 struct rpc_inode *rpci = RPC_I(inode); 703 struct gss_upcall_msg *gss_msg; 704 705 spin_lock(&inode->i_lock); 706 while (!list_empty(&rpci->in_downcall)) { 707 708 gss_msg = list_entry(rpci->in_downcall.next, 709 struct gss_upcall_msg, list); 710 gss_msg->msg.errno = -EPIPE; 711 atomic_inc(&gss_msg->count); 712 __gss_unhash_msg(gss_msg); 713 spin_unlock(&inode->i_lock); 714 gss_release_msg(gss_msg); 715 spin_lock(&inode->i_lock); 716 } 717 spin_unlock(&inode->i_lock); 718 719 put_pipe_version(); 720 } 721 722 static void 723 gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 724 { 725 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 726 727 if (msg->errno < 0) { 728 dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n", 729 gss_msg); 730 atomic_inc(&gss_msg->count); 731 gss_unhash_msg(gss_msg); 732 if (msg->errno == -ETIMEDOUT) 733 warn_gssd(); 734 gss_release_msg(gss_msg); 735 } 736 } 737 738 /* 739 * NOTE: we have the opportunity to use different 740 * parameters based on the input flavor (which must be a pseudoflavor) 741 */ 742 static struct rpc_auth * 743 gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 744 { 745 struct gss_auth *gss_auth; 746 struct rpc_auth * auth; 747 int err = -ENOMEM; /* XXX? */ 748 749 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 750 751 if (!try_module_get(THIS_MODULE)) 752 return ERR_PTR(err); 753 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 754 goto out_dec; 755 gss_auth->client = clnt; 756 err = -EINVAL; 757 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 758 if (!gss_auth->mech) { 759 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 760 __func__, flavor); 761 goto err_free; 762 } 763 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 764 if (gss_auth->service == 0) 765 goto err_put_mech; 766 auth = &gss_auth->rpc_auth; 767 auth->au_cslack = GSS_CRED_SLACK >> 2; 768 auth->au_rslack = GSS_VERF_SLACK >> 2; 769 auth->au_ops = &authgss_ops; 770 auth->au_flavor = flavor; 771 atomic_set(&auth->au_count, 1); 772 kref_init(&gss_auth->kref); 773 774 /* 775 * Note: if we created the old pipe first, then someone who 776 * examined the directory at the right moment might conclude 777 * that we supported only the old pipe. So we instead create 778 * the new pipe first. 779 */ 780 gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_dentry, 781 "gssd", 782 clnt, &gss_upcall_ops_v1, 783 RPC_PIPE_WAIT_FOR_OPEN); 784 if (IS_ERR(gss_auth->dentry[1])) { 785 err = PTR_ERR(gss_auth->dentry[1]); 786 goto err_put_mech; 787 } 788 789 gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_dentry, 790 gss_auth->mech->gm_name, 791 clnt, &gss_upcall_ops_v0, 792 RPC_PIPE_WAIT_FOR_OPEN); 793 if (IS_ERR(gss_auth->dentry[0])) { 794 err = PTR_ERR(gss_auth->dentry[0]); 795 goto err_unlink_pipe_1; 796 } 797 err = rpcauth_init_credcache(auth); 798 if (err) 799 goto err_unlink_pipe_0; 800 801 return auth; 802 err_unlink_pipe_0: 803 rpc_unlink(gss_auth->dentry[0]); 804 err_unlink_pipe_1: 805 rpc_unlink(gss_auth->dentry[1]); 806 err_put_mech: 807 gss_mech_put(gss_auth->mech); 808 err_free: 809 kfree(gss_auth); 810 out_dec: 811 module_put(THIS_MODULE); 812 return ERR_PTR(err); 813 } 814 815 static void 816 gss_free(struct gss_auth *gss_auth) 817 { 818 rpc_unlink(gss_auth->dentry[1]); 819 rpc_unlink(gss_auth->dentry[0]); 820 gss_mech_put(gss_auth->mech); 821 822 kfree(gss_auth); 823 module_put(THIS_MODULE); 824 } 825 826 static void 827 gss_free_callback(struct kref *kref) 828 { 829 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 830 831 gss_free(gss_auth); 832 } 833 834 static void 835 gss_destroy(struct rpc_auth *auth) 836 { 837 struct gss_auth *gss_auth; 838 839 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 840 auth, auth->au_flavor); 841 842 rpcauth_destroy_credcache(auth); 843 844 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 845 kref_put(&gss_auth->kref, gss_free_callback); 846 } 847 848 /* 849 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 850 * to the server with the GSS control procedure field set to 851 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 852 * all RPCSEC_GSS state associated with that context. 853 */ 854 static int 855 gss_destroying_context(struct rpc_cred *cred) 856 { 857 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 858 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 859 struct rpc_task *task; 860 861 if (gss_cred->gc_ctx == NULL || 862 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 863 return 0; 864 865 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 866 cred->cr_ops = &gss_nullops; 867 868 /* Take a reference to ensure the cred will be destroyed either 869 * by the RPC call or by the put_rpccred() below */ 870 get_rpccred(cred); 871 872 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 873 if (!IS_ERR(task)) 874 rpc_put_task(task); 875 876 put_rpccred(cred); 877 return 1; 878 } 879 880 /* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 881 * to create a new cred or context, so they check that things have been 882 * allocated before freeing them. */ 883 static void 884 gss_do_free_ctx(struct gss_cl_ctx *ctx) 885 { 886 dprintk("RPC: gss_free_ctx\n"); 887 888 kfree(ctx->gc_wire_ctx.data); 889 kfree(ctx); 890 } 891 892 static void 893 gss_free_ctx_callback(struct rcu_head *head) 894 { 895 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 896 gss_do_free_ctx(ctx); 897 } 898 899 static void 900 gss_free_ctx(struct gss_cl_ctx *ctx) 901 { 902 struct gss_ctx *gc_gss_ctx; 903 904 gc_gss_ctx = rcu_dereference(ctx->gc_gss_ctx); 905 rcu_assign_pointer(ctx->gc_gss_ctx, NULL); 906 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 907 if (gc_gss_ctx) 908 gss_delete_sec_context(&gc_gss_ctx); 909 } 910 911 static void 912 gss_free_cred(struct gss_cred *gss_cred) 913 { 914 dprintk("RPC: gss_free_cred %p\n", gss_cred); 915 kfree(gss_cred); 916 } 917 918 static void 919 gss_free_cred_callback(struct rcu_head *head) 920 { 921 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 922 gss_free_cred(gss_cred); 923 } 924 925 static void 926 gss_destroy_nullcred(struct rpc_cred *cred) 927 { 928 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 929 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 930 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 931 932 rcu_assign_pointer(gss_cred->gc_ctx, NULL); 933 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 934 if (ctx) 935 gss_put_ctx(ctx); 936 kref_put(&gss_auth->kref, gss_free_callback); 937 } 938 939 static void 940 gss_destroy_cred(struct rpc_cred *cred) 941 { 942 943 if (gss_destroying_context(cred)) 944 return; 945 gss_destroy_nullcred(cred); 946 } 947 948 /* 949 * Lookup RPCSEC_GSS cred for the current process 950 */ 951 static struct rpc_cred * 952 gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 953 { 954 return rpcauth_lookup_credcache(auth, acred, flags); 955 } 956 957 static struct rpc_cred * 958 gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 959 { 960 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 961 struct gss_cred *cred = NULL; 962 int err = -ENOMEM; 963 964 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 965 acred->uid, auth->au_flavor); 966 967 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 968 goto out_err; 969 970 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 971 /* 972 * Note: in order to force a call to call_refresh(), we deliberately 973 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 974 */ 975 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 976 cred->gc_service = gss_auth->service; 977 cred->gc_machine_cred = acred->machine_cred; 978 kref_get(&gss_auth->kref); 979 return &cred->gc_base; 980 981 out_err: 982 dprintk("RPC: gss_create_cred failed with error %d\n", err); 983 return ERR_PTR(err); 984 } 985 986 static int 987 gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 988 { 989 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 990 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 991 int err; 992 993 do { 994 err = gss_create_upcall(gss_auth, gss_cred); 995 } while (err == -EAGAIN); 996 return err; 997 } 998 999 static int 1000 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1001 { 1002 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1003 1004 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1005 goto out; 1006 /* Don't match with creds that have expired. */ 1007 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1008 return 0; 1009 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1010 return 0; 1011 out: 1012 if (acred->machine_cred != gss_cred->gc_machine_cred) 1013 return 0; 1014 return (rc->cr_uid == acred->uid); 1015 } 1016 1017 /* 1018 * Marshal credentials. 1019 * Maybe we should keep a cached credential for performance reasons. 1020 */ 1021 static __be32 * 1022 gss_marshal(struct rpc_task *task, __be32 *p) 1023 { 1024 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1025 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1026 gc_base); 1027 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1028 __be32 *cred_len; 1029 struct rpc_rqst *req = task->tk_rqstp; 1030 u32 maj_stat = 0; 1031 struct xdr_netobj mic; 1032 struct kvec iov; 1033 struct xdr_buf verf_buf; 1034 1035 dprintk("RPC: %5u gss_marshal\n", task->tk_pid); 1036 1037 *p++ = htonl(RPC_AUTH_GSS); 1038 cred_len = p++; 1039 1040 spin_lock(&ctx->gc_seq_lock); 1041 req->rq_seqno = ctx->gc_seq++; 1042 spin_unlock(&ctx->gc_seq_lock); 1043 1044 *p++ = htonl((u32) RPC_GSS_VERSION); 1045 *p++ = htonl((u32) ctx->gc_proc); 1046 *p++ = htonl((u32) req->rq_seqno); 1047 *p++ = htonl((u32) gss_cred->gc_service); 1048 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1049 *cred_len = htonl((p - (cred_len + 1)) << 2); 1050 1051 /* We compute the checksum for the verifier over the xdr-encoded bytes 1052 * starting with the xid and ending at the end of the credential: */ 1053 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 1054 req->rq_snd_buf.head[0].iov_base); 1055 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1056 xdr_buf_from_iov(&iov, &verf_buf); 1057 1058 /* set verifier flavor*/ 1059 *p++ = htonl(RPC_AUTH_GSS); 1060 1061 mic.data = (u8 *)(p + 1); 1062 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1063 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1064 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1065 } else if (maj_stat != 0) { 1066 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1067 goto out_put_ctx; 1068 } 1069 p = xdr_encode_opaque(p, NULL, mic.len); 1070 gss_put_ctx(ctx); 1071 return p; 1072 out_put_ctx: 1073 gss_put_ctx(ctx); 1074 return NULL; 1075 } 1076 1077 static int gss_renew_cred(struct rpc_task *task) 1078 { 1079 struct rpc_cred *oldcred = task->tk_msg.rpc_cred; 1080 struct gss_cred *gss_cred = container_of(oldcred, 1081 struct gss_cred, 1082 gc_base); 1083 struct rpc_auth *auth = oldcred->cr_auth; 1084 struct auth_cred acred = { 1085 .uid = oldcred->cr_uid, 1086 .machine_cred = gss_cred->gc_machine_cred, 1087 }; 1088 struct rpc_cred *new; 1089 1090 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1091 if (IS_ERR(new)) 1092 return PTR_ERR(new); 1093 task->tk_msg.rpc_cred = new; 1094 put_rpccred(oldcred); 1095 return 0; 1096 } 1097 1098 /* 1099 * Refresh credentials. XXX - finish 1100 */ 1101 static int 1102 gss_refresh(struct rpc_task *task) 1103 { 1104 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1105 int ret = 0; 1106 1107 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1108 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1109 ret = gss_renew_cred(task); 1110 if (ret < 0) 1111 goto out; 1112 cred = task->tk_msg.rpc_cred; 1113 } 1114 1115 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1116 ret = gss_refresh_upcall(task); 1117 out: 1118 return ret; 1119 } 1120 1121 /* Dummy refresh routine: used only when destroying the context */ 1122 static int 1123 gss_refresh_null(struct rpc_task *task) 1124 { 1125 return -EACCES; 1126 } 1127 1128 static __be32 * 1129 gss_validate(struct rpc_task *task, __be32 *p) 1130 { 1131 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1132 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1133 __be32 seq; 1134 struct kvec iov; 1135 struct xdr_buf verf_buf; 1136 struct xdr_netobj mic; 1137 u32 flav,len; 1138 u32 maj_stat; 1139 1140 dprintk("RPC: %5u gss_validate\n", task->tk_pid); 1141 1142 flav = ntohl(*p++); 1143 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1144 goto out_bad; 1145 if (flav != RPC_AUTH_GSS) 1146 goto out_bad; 1147 seq = htonl(task->tk_rqstp->rq_seqno); 1148 iov.iov_base = &seq; 1149 iov.iov_len = sizeof(seq); 1150 xdr_buf_from_iov(&iov, &verf_buf); 1151 mic.data = (u8 *)p; 1152 mic.len = len; 1153 1154 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1155 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1156 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1157 if (maj_stat) { 1158 dprintk("RPC: %5u gss_validate: gss_verify_mic returned " 1159 "error 0x%08x\n", task->tk_pid, maj_stat); 1160 goto out_bad; 1161 } 1162 /* We leave it to unwrap to calculate au_rslack. For now we just 1163 * calculate the length of the verifier: */ 1164 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1165 gss_put_ctx(ctx); 1166 dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n", 1167 task->tk_pid); 1168 return p + XDR_QUADLEN(len); 1169 out_bad: 1170 gss_put_ctx(ctx); 1171 dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid); 1172 return NULL; 1173 } 1174 1175 static inline int 1176 gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1177 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1178 { 1179 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1180 struct xdr_buf integ_buf; 1181 __be32 *integ_len = NULL; 1182 struct xdr_netobj mic; 1183 u32 offset; 1184 __be32 *q; 1185 struct kvec *iov; 1186 u32 maj_stat = 0; 1187 int status = -EIO; 1188 1189 integ_len = p++; 1190 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1191 *p++ = htonl(rqstp->rq_seqno); 1192 1193 status = encode(rqstp, p, obj); 1194 if (status) 1195 return status; 1196 1197 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1198 offset, snd_buf->len - offset)) 1199 return status; 1200 *integ_len = htonl(integ_buf.len); 1201 1202 /* guess whether we're in the head or the tail: */ 1203 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1204 iov = snd_buf->tail; 1205 else 1206 iov = snd_buf->head; 1207 p = iov->iov_base + iov->iov_len; 1208 mic.data = (u8 *)(p + 1); 1209 1210 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1211 status = -EIO; /* XXX? */ 1212 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1213 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1214 else if (maj_stat) 1215 return status; 1216 q = xdr_encode_opaque(p, NULL, mic.len); 1217 1218 offset = (u8 *)q - (u8 *)p; 1219 iov->iov_len += offset; 1220 snd_buf->len += offset; 1221 return 0; 1222 } 1223 1224 static void 1225 priv_release_snd_buf(struct rpc_rqst *rqstp) 1226 { 1227 int i; 1228 1229 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1230 __free_page(rqstp->rq_enc_pages[i]); 1231 kfree(rqstp->rq_enc_pages); 1232 } 1233 1234 static int 1235 alloc_enc_pages(struct rpc_rqst *rqstp) 1236 { 1237 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1238 int first, last, i; 1239 1240 if (snd_buf->page_len == 0) { 1241 rqstp->rq_enc_pages_num = 0; 1242 return 0; 1243 } 1244 1245 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1246 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1247 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1248 rqstp->rq_enc_pages 1249 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1250 GFP_NOFS); 1251 if (!rqstp->rq_enc_pages) 1252 goto out; 1253 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1254 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1255 if (rqstp->rq_enc_pages[i] == NULL) 1256 goto out_free; 1257 } 1258 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1259 return 0; 1260 out_free: 1261 for (i--; i >= 0; i--) { 1262 __free_page(rqstp->rq_enc_pages[i]); 1263 } 1264 out: 1265 return -EAGAIN; 1266 } 1267 1268 static inline int 1269 gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1270 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1271 { 1272 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1273 u32 offset; 1274 u32 maj_stat; 1275 int status; 1276 __be32 *opaque_len; 1277 struct page **inpages; 1278 int first; 1279 int pad; 1280 struct kvec *iov; 1281 char *tmp; 1282 1283 opaque_len = p++; 1284 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1285 *p++ = htonl(rqstp->rq_seqno); 1286 1287 status = encode(rqstp, p, obj); 1288 if (status) 1289 return status; 1290 1291 status = alloc_enc_pages(rqstp); 1292 if (status) 1293 return status; 1294 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1295 inpages = snd_buf->pages + first; 1296 snd_buf->pages = rqstp->rq_enc_pages; 1297 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1298 /* Give the tail its own page, in case we need extra space in the 1299 * head when wrapping: */ 1300 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1301 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1302 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1303 snd_buf->tail[0].iov_base = tmp; 1304 } 1305 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1306 /* RPC_SLACK_SPACE should prevent this ever happening: */ 1307 BUG_ON(snd_buf->len > snd_buf->buflen); 1308 status = -EIO; 1309 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1310 * done anyway, so it's safe to put the request on the wire: */ 1311 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1312 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1313 else if (maj_stat) 1314 return status; 1315 1316 *opaque_len = htonl(snd_buf->len - offset); 1317 /* guess whether we're in the head or the tail: */ 1318 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1319 iov = snd_buf->tail; 1320 else 1321 iov = snd_buf->head; 1322 p = iov->iov_base + iov->iov_len; 1323 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1324 memset(p, 0, pad); 1325 iov->iov_len += pad; 1326 snd_buf->len += pad; 1327 1328 return 0; 1329 } 1330 1331 static int 1332 gss_wrap_req(struct rpc_task *task, 1333 kxdrproc_t encode, void *rqstp, __be32 *p, void *obj) 1334 { 1335 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1336 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1337 gc_base); 1338 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1339 int status = -EIO; 1340 1341 dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid); 1342 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1343 /* The spec seems a little ambiguous here, but I think that not 1344 * wrapping context destruction requests makes the most sense. 1345 */ 1346 status = encode(rqstp, p, obj); 1347 goto out; 1348 } 1349 switch (gss_cred->gc_service) { 1350 case RPC_GSS_SVC_NONE: 1351 status = encode(rqstp, p, obj); 1352 break; 1353 case RPC_GSS_SVC_INTEGRITY: 1354 status = gss_wrap_req_integ(cred, ctx, encode, 1355 rqstp, p, obj); 1356 break; 1357 case RPC_GSS_SVC_PRIVACY: 1358 status = gss_wrap_req_priv(cred, ctx, encode, 1359 rqstp, p, obj); 1360 break; 1361 } 1362 out: 1363 gss_put_ctx(ctx); 1364 dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status); 1365 return status; 1366 } 1367 1368 static inline int 1369 gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1370 struct rpc_rqst *rqstp, __be32 **p) 1371 { 1372 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1373 struct xdr_buf integ_buf; 1374 struct xdr_netobj mic; 1375 u32 data_offset, mic_offset; 1376 u32 integ_len; 1377 u32 maj_stat; 1378 int status = -EIO; 1379 1380 integ_len = ntohl(*(*p)++); 1381 if (integ_len & 3) 1382 return status; 1383 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1384 mic_offset = integ_len + data_offset; 1385 if (mic_offset > rcv_buf->len) 1386 return status; 1387 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1388 return status; 1389 1390 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1391 mic_offset - data_offset)) 1392 return status; 1393 1394 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1395 return status; 1396 1397 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1398 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1399 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1400 if (maj_stat != GSS_S_COMPLETE) 1401 return status; 1402 return 0; 1403 } 1404 1405 static inline int 1406 gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1407 struct rpc_rqst *rqstp, __be32 **p) 1408 { 1409 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1410 u32 offset; 1411 u32 opaque_len; 1412 u32 maj_stat; 1413 int status = -EIO; 1414 1415 opaque_len = ntohl(*(*p)++); 1416 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1417 if (offset + opaque_len > rcv_buf->len) 1418 return status; 1419 /* remove padding: */ 1420 rcv_buf->len = offset + opaque_len; 1421 1422 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1423 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1424 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1425 if (maj_stat != GSS_S_COMPLETE) 1426 return status; 1427 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1428 return status; 1429 1430 return 0; 1431 } 1432 1433 1434 static int 1435 gss_unwrap_resp(struct rpc_task *task, 1436 kxdrproc_t decode, void *rqstp, __be32 *p, void *obj) 1437 { 1438 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1439 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1440 gc_base); 1441 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1442 __be32 *savedp = p; 1443 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1444 int savedlen = head->iov_len; 1445 int status = -EIO; 1446 1447 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1448 goto out_decode; 1449 switch (gss_cred->gc_service) { 1450 case RPC_GSS_SVC_NONE: 1451 break; 1452 case RPC_GSS_SVC_INTEGRITY: 1453 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1454 if (status) 1455 goto out; 1456 break; 1457 case RPC_GSS_SVC_PRIVACY: 1458 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1459 if (status) 1460 goto out; 1461 break; 1462 } 1463 /* take into account extra slack for integrity and privacy cases: */ 1464 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1465 + (savedlen - head->iov_len); 1466 out_decode: 1467 status = decode(rqstp, p, obj); 1468 out: 1469 gss_put_ctx(ctx); 1470 dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid, 1471 status); 1472 return status; 1473 } 1474 1475 static const struct rpc_authops authgss_ops = { 1476 .owner = THIS_MODULE, 1477 .au_flavor = RPC_AUTH_GSS, 1478 .au_name = "RPCSEC_GSS", 1479 .create = gss_create, 1480 .destroy = gss_destroy, 1481 .lookup_cred = gss_lookup_cred, 1482 .crcreate = gss_create_cred 1483 }; 1484 1485 static const struct rpc_credops gss_credops = { 1486 .cr_name = "AUTH_GSS", 1487 .crdestroy = gss_destroy_cred, 1488 .cr_init = gss_cred_init, 1489 .crbind = rpcauth_generic_bind_cred, 1490 .crmatch = gss_match, 1491 .crmarshal = gss_marshal, 1492 .crrefresh = gss_refresh, 1493 .crvalidate = gss_validate, 1494 .crwrap_req = gss_wrap_req, 1495 .crunwrap_resp = gss_unwrap_resp, 1496 }; 1497 1498 static const struct rpc_credops gss_nullops = { 1499 .cr_name = "AUTH_GSS", 1500 .crdestroy = gss_destroy_nullcred, 1501 .crbind = rpcauth_generic_bind_cred, 1502 .crmatch = gss_match, 1503 .crmarshal = gss_marshal, 1504 .crrefresh = gss_refresh_null, 1505 .crvalidate = gss_validate, 1506 .crwrap_req = gss_wrap_req, 1507 .crunwrap_resp = gss_unwrap_resp, 1508 }; 1509 1510 static struct rpc_pipe_ops gss_upcall_ops_v0 = { 1511 .upcall = gss_pipe_upcall, 1512 .downcall = gss_pipe_downcall, 1513 .destroy_msg = gss_pipe_destroy_msg, 1514 .open_pipe = gss_pipe_open_v0, 1515 .release_pipe = gss_pipe_release, 1516 }; 1517 1518 static struct rpc_pipe_ops gss_upcall_ops_v1 = { 1519 .upcall = gss_pipe_upcall, 1520 .downcall = gss_pipe_downcall, 1521 .destroy_msg = gss_pipe_destroy_msg, 1522 .open_pipe = gss_pipe_open_v1, 1523 .release_pipe = gss_pipe_release, 1524 }; 1525 1526 /* 1527 * Initialize RPCSEC_GSS module 1528 */ 1529 static int __init init_rpcsec_gss(void) 1530 { 1531 int err = 0; 1532 1533 err = rpcauth_register(&authgss_ops); 1534 if (err) 1535 goto out; 1536 err = gss_svc_init(); 1537 if (err) 1538 goto out_unregister; 1539 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1540 return 0; 1541 out_unregister: 1542 rpcauth_unregister(&authgss_ops); 1543 out: 1544 return err; 1545 } 1546 1547 static void __exit exit_rpcsec_gss(void) 1548 { 1549 gss_svc_shutdown(); 1550 rpcauth_unregister(&authgss_ops); 1551 } 1552 1553 MODULE_LICENSE("GPL"); 1554 module_init(init_rpcsec_gss) 1555 module_exit(exit_rpcsec_gss) 1556