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 const struct rpc_pipe_ops gss_upcall_ops_v0; 93 static const 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_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_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 (PTR_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 switch (err) { 648 case -EACCES: 649 gss_msg->msg.errno = err; 650 err = mlen; 651 break; 652 case -EFAULT: 653 case -ENOMEM: 654 case -EINVAL: 655 case -ENOSYS: 656 gss_msg->msg.errno = -EAGAIN; 657 break; 658 default: 659 printk(KERN_CRIT "%s: bad return from " 660 "gss_fill_context: %zd\n", __func__, err); 661 BUG(); 662 } 663 goto err_release_msg; 664 } 665 gss_msg->ctx = gss_get_ctx(ctx); 666 err = mlen; 667 668 err_release_msg: 669 spin_lock(&inode->i_lock); 670 __gss_unhash_msg(gss_msg); 671 spin_unlock(&inode->i_lock); 672 gss_release_msg(gss_msg); 673 err_put_ctx: 674 gss_put_ctx(ctx); 675 err: 676 kfree(buf); 677 out: 678 dprintk("RPC: gss_pipe_downcall returning %Zd\n", err); 679 return err; 680 } 681 682 static int gss_pipe_open(struct inode *inode, int new_version) 683 { 684 int ret = 0; 685 686 spin_lock(&pipe_version_lock); 687 if (pipe_version < 0) { 688 /* First open of any gss pipe determines the version: */ 689 pipe_version = new_version; 690 rpc_wake_up(&pipe_version_rpc_waitqueue); 691 wake_up(&pipe_version_waitqueue); 692 } else if (pipe_version != new_version) { 693 /* Trying to open a pipe of a different version */ 694 ret = -EBUSY; 695 goto out; 696 } 697 atomic_inc(&pipe_users); 698 out: 699 spin_unlock(&pipe_version_lock); 700 return ret; 701 702 } 703 704 static int gss_pipe_open_v0(struct inode *inode) 705 { 706 return gss_pipe_open(inode, 0); 707 } 708 709 static int gss_pipe_open_v1(struct inode *inode) 710 { 711 return gss_pipe_open(inode, 1); 712 } 713 714 static void 715 gss_pipe_release(struct inode *inode) 716 { 717 struct rpc_inode *rpci = RPC_I(inode); 718 struct gss_upcall_msg *gss_msg; 719 720 spin_lock(&inode->i_lock); 721 while (!list_empty(&rpci->in_downcall)) { 722 723 gss_msg = list_entry(rpci->in_downcall.next, 724 struct gss_upcall_msg, list); 725 gss_msg->msg.errno = -EPIPE; 726 atomic_inc(&gss_msg->count); 727 __gss_unhash_msg(gss_msg); 728 spin_unlock(&inode->i_lock); 729 gss_release_msg(gss_msg); 730 spin_lock(&inode->i_lock); 731 } 732 spin_unlock(&inode->i_lock); 733 734 put_pipe_version(); 735 } 736 737 static void 738 gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 739 { 740 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 741 742 if (msg->errno < 0) { 743 dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n", 744 gss_msg); 745 atomic_inc(&gss_msg->count); 746 gss_unhash_msg(gss_msg); 747 if (msg->errno == -ETIMEDOUT) 748 warn_gssd(); 749 gss_release_msg(gss_msg); 750 } 751 } 752 753 /* 754 * NOTE: we have the opportunity to use different 755 * parameters based on the input flavor (which must be a pseudoflavor) 756 */ 757 static struct rpc_auth * 758 gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 759 { 760 struct gss_auth *gss_auth; 761 struct rpc_auth * auth; 762 int err = -ENOMEM; /* XXX? */ 763 764 dprintk("RPC: creating GSS authenticator for client %p\n", clnt); 765 766 if (!try_module_get(THIS_MODULE)) 767 return ERR_PTR(err); 768 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 769 goto out_dec; 770 gss_auth->client = clnt; 771 err = -EINVAL; 772 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 773 if (!gss_auth->mech) { 774 printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n", 775 __func__, flavor); 776 goto err_free; 777 } 778 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 779 if (gss_auth->service == 0) 780 goto err_put_mech; 781 auth = &gss_auth->rpc_auth; 782 auth->au_cslack = GSS_CRED_SLACK >> 2; 783 auth->au_rslack = GSS_VERF_SLACK >> 2; 784 auth->au_ops = &authgss_ops; 785 auth->au_flavor = flavor; 786 atomic_set(&auth->au_count, 1); 787 kref_init(&gss_auth->kref); 788 789 /* 790 * Note: if we created the old pipe first, then someone who 791 * examined the directory at the right moment might conclude 792 * that we supported only the old pipe. So we instead create 793 * the new pipe first. 794 */ 795 gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_path.dentry, 796 "gssd", 797 clnt, &gss_upcall_ops_v1, 798 RPC_PIPE_WAIT_FOR_OPEN); 799 if (IS_ERR(gss_auth->dentry[1])) { 800 err = PTR_ERR(gss_auth->dentry[1]); 801 goto err_put_mech; 802 } 803 804 gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_path.dentry, 805 gss_auth->mech->gm_name, 806 clnt, &gss_upcall_ops_v0, 807 RPC_PIPE_WAIT_FOR_OPEN); 808 if (IS_ERR(gss_auth->dentry[0])) { 809 err = PTR_ERR(gss_auth->dentry[0]); 810 goto err_unlink_pipe_1; 811 } 812 err = rpcauth_init_credcache(auth); 813 if (err) 814 goto err_unlink_pipe_0; 815 816 return auth; 817 err_unlink_pipe_0: 818 rpc_unlink(gss_auth->dentry[0]); 819 err_unlink_pipe_1: 820 rpc_unlink(gss_auth->dentry[1]); 821 err_put_mech: 822 gss_mech_put(gss_auth->mech); 823 err_free: 824 kfree(gss_auth); 825 out_dec: 826 module_put(THIS_MODULE); 827 return ERR_PTR(err); 828 } 829 830 static void 831 gss_free(struct gss_auth *gss_auth) 832 { 833 rpc_unlink(gss_auth->dentry[1]); 834 rpc_unlink(gss_auth->dentry[0]); 835 gss_mech_put(gss_auth->mech); 836 837 kfree(gss_auth); 838 module_put(THIS_MODULE); 839 } 840 841 static void 842 gss_free_callback(struct kref *kref) 843 { 844 struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref); 845 846 gss_free(gss_auth); 847 } 848 849 static void 850 gss_destroy(struct rpc_auth *auth) 851 { 852 struct gss_auth *gss_auth; 853 854 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 855 auth, auth->au_flavor); 856 857 rpcauth_destroy_credcache(auth); 858 859 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 860 kref_put(&gss_auth->kref, gss_free_callback); 861 } 862 863 /* 864 * gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call 865 * to the server with the GSS control procedure field set to 866 * RPC_GSS_PROC_DESTROY. This should normally cause the server to release 867 * all RPCSEC_GSS state associated with that context. 868 */ 869 static int 870 gss_destroying_context(struct rpc_cred *cred) 871 { 872 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 873 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 874 struct rpc_task *task; 875 876 if (gss_cred->gc_ctx == NULL || 877 test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) 878 return 0; 879 880 gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY; 881 cred->cr_ops = &gss_nullops; 882 883 /* Take a reference to ensure the cred will be destroyed either 884 * by the RPC call or by the put_rpccred() below */ 885 get_rpccred(cred); 886 887 task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT); 888 if (!IS_ERR(task)) 889 rpc_put_task(task); 890 891 put_rpccred(cred); 892 return 1; 893 } 894 895 /* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure 896 * to create a new cred or context, so they check that things have been 897 * allocated before freeing them. */ 898 static void 899 gss_do_free_ctx(struct gss_cl_ctx *ctx) 900 { 901 dprintk("RPC: gss_free_ctx\n"); 902 903 kfree(ctx->gc_wire_ctx.data); 904 kfree(ctx); 905 } 906 907 static void 908 gss_free_ctx_callback(struct rcu_head *head) 909 { 910 struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu); 911 gss_do_free_ctx(ctx); 912 } 913 914 static void 915 gss_free_ctx(struct gss_cl_ctx *ctx) 916 { 917 struct gss_ctx *gc_gss_ctx; 918 919 gc_gss_ctx = rcu_dereference(ctx->gc_gss_ctx); 920 rcu_assign_pointer(ctx->gc_gss_ctx, NULL); 921 call_rcu(&ctx->gc_rcu, gss_free_ctx_callback); 922 if (gc_gss_ctx) 923 gss_delete_sec_context(&gc_gss_ctx); 924 } 925 926 static void 927 gss_free_cred(struct gss_cred *gss_cred) 928 { 929 dprintk("RPC: gss_free_cred %p\n", gss_cred); 930 kfree(gss_cred); 931 } 932 933 static void 934 gss_free_cred_callback(struct rcu_head *head) 935 { 936 struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu); 937 gss_free_cred(gss_cred); 938 } 939 940 static void 941 gss_destroy_nullcred(struct rpc_cred *cred) 942 { 943 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 944 struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth); 945 struct gss_cl_ctx *ctx = gss_cred->gc_ctx; 946 947 rcu_assign_pointer(gss_cred->gc_ctx, NULL); 948 call_rcu(&cred->cr_rcu, gss_free_cred_callback); 949 if (ctx) 950 gss_put_ctx(ctx); 951 kref_put(&gss_auth->kref, gss_free_callback); 952 } 953 954 static void 955 gss_destroy_cred(struct rpc_cred *cred) 956 { 957 958 if (gss_destroying_context(cred)) 959 return; 960 gss_destroy_nullcred(cred); 961 } 962 963 /* 964 * Lookup RPCSEC_GSS cred for the current process 965 */ 966 static struct rpc_cred * 967 gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 968 { 969 return rpcauth_lookup_credcache(auth, acred, flags); 970 } 971 972 static struct rpc_cred * 973 gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 974 { 975 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 976 struct gss_cred *cred = NULL; 977 int err = -ENOMEM; 978 979 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 980 acred->uid, auth->au_flavor); 981 982 if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS))) 983 goto out_err; 984 985 rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops); 986 /* 987 * Note: in order to force a call to call_refresh(), we deliberately 988 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 989 */ 990 cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW; 991 cred->gc_service = gss_auth->service; 992 cred->gc_machine_cred = acred->machine_cred; 993 kref_get(&gss_auth->kref); 994 return &cred->gc_base; 995 996 out_err: 997 dprintk("RPC: gss_create_cred failed with error %d\n", err); 998 return ERR_PTR(err); 999 } 1000 1001 static int 1002 gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred) 1003 { 1004 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 1005 struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base); 1006 int err; 1007 1008 do { 1009 err = gss_create_upcall(gss_auth, gss_cred); 1010 } while (err == -EAGAIN); 1011 return err; 1012 } 1013 1014 static int 1015 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags) 1016 { 1017 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 1018 1019 if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags)) 1020 goto out; 1021 /* Don't match with creds that have expired. */ 1022 if (time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 1023 return 0; 1024 if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags)) 1025 return 0; 1026 out: 1027 if (acred->machine_cred != gss_cred->gc_machine_cred) 1028 return 0; 1029 return (rc->cr_uid == acred->uid); 1030 } 1031 1032 /* 1033 * Marshal credentials. 1034 * Maybe we should keep a cached credential for performance reasons. 1035 */ 1036 static __be32 * 1037 gss_marshal(struct rpc_task *task, __be32 *p) 1038 { 1039 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1040 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1041 gc_base); 1042 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1043 __be32 *cred_len; 1044 struct rpc_rqst *req = task->tk_rqstp; 1045 u32 maj_stat = 0; 1046 struct xdr_netobj mic; 1047 struct kvec iov; 1048 struct xdr_buf verf_buf; 1049 1050 dprintk("RPC: %5u gss_marshal\n", task->tk_pid); 1051 1052 *p++ = htonl(RPC_AUTH_GSS); 1053 cred_len = p++; 1054 1055 spin_lock(&ctx->gc_seq_lock); 1056 req->rq_seqno = ctx->gc_seq++; 1057 spin_unlock(&ctx->gc_seq_lock); 1058 1059 *p++ = htonl((u32) RPC_GSS_VERSION); 1060 *p++ = htonl((u32) ctx->gc_proc); 1061 *p++ = htonl((u32) req->rq_seqno); 1062 *p++ = htonl((u32) gss_cred->gc_service); 1063 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 1064 *cred_len = htonl((p - (cred_len + 1)) << 2); 1065 1066 /* We compute the checksum for the verifier over the xdr-encoded bytes 1067 * starting with the xid and ending at the end of the credential: */ 1068 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 1069 req->rq_snd_buf.head[0].iov_base); 1070 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 1071 xdr_buf_from_iov(&iov, &verf_buf); 1072 1073 /* set verifier flavor*/ 1074 *p++ = htonl(RPC_AUTH_GSS); 1075 1076 mic.data = (u8 *)(p + 1); 1077 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1078 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 1079 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1080 } else if (maj_stat != 0) { 1081 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 1082 goto out_put_ctx; 1083 } 1084 p = xdr_encode_opaque(p, NULL, mic.len); 1085 gss_put_ctx(ctx); 1086 return p; 1087 out_put_ctx: 1088 gss_put_ctx(ctx); 1089 return NULL; 1090 } 1091 1092 static int gss_renew_cred(struct rpc_task *task) 1093 { 1094 struct rpc_cred *oldcred = task->tk_msg.rpc_cred; 1095 struct gss_cred *gss_cred = container_of(oldcred, 1096 struct gss_cred, 1097 gc_base); 1098 struct rpc_auth *auth = oldcred->cr_auth; 1099 struct auth_cred acred = { 1100 .uid = oldcred->cr_uid, 1101 .machine_cred = gss_cred->gc_machine_cred, 1102 }; 1103 struct rpc_cred *new; 1104 1105 new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW); 1106 if (IS_ERR(new)) 1107 return PTR_ERR(new); 1108 task->tk_msg.rpc_cred = new; 1109 put_rpccred(oldcred); 1110 return 0; 1111 } 1112 1113 /* 1114 * Refresh credentials. XXX - finish 1115 */ 1116 static int 1117 gss_refresh(struct rpc_task *task) 1118 { 1119 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1120 int ret = 0; 1121 1122 if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && 1123 !test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) { 1124 ret = gss_renew_cred(task); 1125 if (ret < 0) 1126 goto out; 1127 cred = task->tk_msg.rpc_cred; 1128 } 1129 1130 if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)) 1131 ret = gss_refresh_upcall(task); 1132 out: 1133 return ret; 1134 } 1135 1136 /* Dummy refresh routine: used only when destroying the context */ 1137 static int 1138 gss_refresh_null(struct rpc_task *task) 1139 { 1140 return -EACCES; 1141 } 1142 1143 static __be32 * 1144 gss_validate(struct rpc_task *task, __be32 *p) 1145 { 1146 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1147 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1148 __be32 seq; 1149 struct kvec iov; 1150 struct xdr_buf verf_buf; 1151 struct xdr_netobj mic; 1152 u32 flav,len; 1153 u32 maj_stat; 1154 1155 dprintk("RPC: %5u gss_validate\n", task->tk_pid); 1156 1157 flav = ntohl(*p++); 1158 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 1159 goto out_bad; 1160 if (flav != RPC_AUTH_GSS) 1161 goto out_bad; 1162 seq = htonl(task->tk_rqstp->rq_seqno); 1163 iov.iov_base = &seq; 1164 iov.iov_len = sizeof(seq); 1165 xdr_buf_from_iov(&iov, &verf_buf); 1166 mic.data = (u8 *)p; 1167 mic.len = len; 1168 1169 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic); 1170 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1171 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1172 if (maj_stat) { 1173 dprintk("RPC: %5u gss_validate: gss_verify_mic returned " 1174 "error 0x%08x\n", task->tk_pid, maj_stat); 1175 goto out_bad; 1176 } 1177 /* We leave it to unwrap to calculate au_rslack. For now we just 1178 * calculate the length of the verifier: */ 1179 cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2; 1180 gss_put_ctx(ctx); 1181 dprintk("RPC: %5u gss_validate: gss_verify_mic succeeded.\n", 1182 task->tk_pid); 1183 return p + XDR_QUADLEN(len); 1184 out_bad: 1185 gss_put_ctx(ctx); 1186 dprintk("RPC: %5u gss_validate failed.\n", task->tk_pid); 1187 return NULL; 1188 } 1189 1190 static inline int 1191 gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1192 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1193 { 1194 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1195 struct xdr_buf integ_buf; 1196 __be32 *integ_len = NULL; 1197 struct xdr_netobj mic; 1198 u32 offset; 1199 __be32 *q; 1200 struct kvec *iov; 1201 u32 maj_stat = 0; 1202 int status = -EIO; 1203 1204 integ_len = p++; 1205 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1206 *p++ = htonl(rqstp->rq_seqno); 1207 1208 status = encode(rqstp, p, obj); 1209 if (status) 1210 return status; 1211 1212 if (xdr_buf_subsegment(snd_buf, &integ_buf, 1213 offset, snd_buf->len - offset)) 1214 return status; 1215 *integ_len = htonl(integ_buf.len); 1216 1217 /* guess whether we're in the head or the tail: */ 1218 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1219 iov = snd_buf->tail; 1220 else 1221 iov = snd_buf->head; 1222 p = iov->iov_base + iov->iov_len; 1223 mic.data = (u8 *)(p + 1); 1224 1225 maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1226 status = -EIO; /* XXX? */ 1227 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1228 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1229 else if (maj_stat) 1230 return status; 1231 q = xdr_encode_opaque(p, NULL, mic.len); 1232 1233 offset = (u8 *)q - (u8 *)p; 1234 iov->iov_len += offset; 1235 snd_buf->len += offset; 1236 return 0; 1237 } 1238 1239 static void 1240 priv_release_snd_buf(struct rpc_rqst *rqstp) 1241 { 1242 int i; 1243 1244 for (i=0; i < rqstp->rq_enc_pages_num; i++) 1245 __free_page(rqstp->rq_enc_pages[i]); 1246 kfree(rqstp->rq_enc_pages); 1247 } 1248 1249 static int 1250 alloc_enc_pages(struct rpc_rqst *rqstp) 1251 { 1252 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1253 int first, last, i; 1254 1255 if (snd_buf->page_len == 0) { 1256 rqstp->rq_enc_pages_num = 0; 1257 return 0; 1258 } 1259 1260 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1261 last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT; 1262 rqstp->rq_enc_pages_num = last - first + 1 + 1; 1263 rqstp->rq_enc_pages 1264 = kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *), 1265 GFP_NOFS); 1266 if (!rqstp->rq_enc_pages) 1267 goto out; 1268 for (i=0; i < rqstp->rq_enc_pages_num; i++) { 1269 rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS); 1270 if (rqstp->rq_enc_pages[i] == NULL) 1271 goto out_free; 1272 } 1273 rqstp->rq_release_snd_buf = priv_release_snd_buf; 1274 return 0; 1275 out_free: 1276 for (i--; i >= 0; i--) { 1277 __free_page(rqstp->rq_enc_pages[i]); 1278 } 1279 out: 1280 return -EAGAIN; 1281 } 1282 1283 static inline int 1284 gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1285 kxdrproc_t encode, struct rpc_rqst *rqstp, __be32 *p, void *obj) 1286 { 1287 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 1288 u32 offset; 1289 u32 maj_stat; 1290 int status; 1291 __be32 *opaque_len; 1292 struct page **inpages; 1293 int first; 1294 int pad; 1295 struct kvec *iov; 1296 char *tmp; 1297 1298 opaque_len = p++; 1299 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 1300 *p++ = htonl(rqstp->rq_seqno); 1301 1302 status = encode(rqstp, p, obj); 1303 if (status) 1304 return status; 1305 1306 status = alloc_enc_pages(rqstp); 1307 if (status) 1308 return status; 1309 first = snd_buf->page_base >> PAGE_CACHE_SHIFT; 1310 inpages = snd_buf->pages + first; 1311 snd_buf->pages = rqstp->rq_enc_pages; 1312 snd_buf->page_base -= first << PAGE_CACHE_SHIFT; 1313 /* Give the tail its own page, in case we need extra space in the 1314 * head when wrapping: */ 1315 if (snd_buf->page_len || snd_buf->tail[0].iov_len) { 1316 tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]); 1317 memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len); 1318 snd_buf->tail[0].iov_base = tmp; 1319 } 1320 maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages); 1321 /* RPC_SLACK_SPACE should prevent this ever happening: */ 1322 BUG_ON(snd_buf->len > snd_buf->buflen); 1323 status = -EIO; 1324 /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was 1325 * done anyway, so it's safe to put the request on the wire: */ 1326 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1327 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1328 else if (maj_stat) 1329 return status; 1330 1331 *opaque_len = htonl(snd_buf->len - offset); 1332 /* guess whether we're in the head or the tail: */ 1333 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 1334 iov = snd_buf->tail; 1335 else 1336 iov = snd_buf->head; 1337 p = iov->iov_base + iov->iov_len; 1338 pad = 3 - ((snd_buf->len - offset - 1) & 3); 1339 memset(p, 0, pad); 1340 iov->iov_len += pad; 1341 snd_buf->len += pad; 1342 1343 return 0; 1344 } 1345 1346 static int 1347 gss_wrap_req(struct rpc_task *task, 1348 kxdrproc_t encode, void *rqstp, __be32 *p, void *obj) 1349 { 1350 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1351 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1352 gc_base); 1353 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1354 int status = -EIO; 1355 1356 dprintk("RPC: %5u gss_wrap_req\n", task->tk_pid); 1357 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1358 /* The spec seems a little ambiguous here, but I think that not 1359 * wrapping context destruction requests makes the most sense. 1360 */ 1361 status = encode(rqstp, p, obj); 1362 goto out; 1363 } 1364 switch (gss_cred->gc_service) { 1365 case RPC_GSS_SVC_NONE: 1366 status = encode(rqstp, p, obj); 1367 break; 1368 case RPC_GSS_SVC_INTEGRITY: 1369 status = gss_wrap_req_integ(cred, ctx, encode, 1370 rqstp, p, obj); 1371 break; 1372 case RPC_GSS_SVC_PRIVACY: 1373 status = gss_wrap_req_priv(cred, ctx, encode, 1374 rqstp, p, obj); 1375 break; 1376 } 1377 out: 1378 gss_put_ctx(ctx); 1379 dprintk("RPC: %5u gss_wrap_req returning %d\n", task->tk_pid, status); 1380 return status; 1381 } 1382 1383 static inline int 1384 gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1385 struct rpc_rqst *rqstp, __be32 **p) 1386 { 1387 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1388 struct xdr_buf integ_buf; 1389 struct xdr_netobj mic; 1390 u32 data_offset, mic_offset; 1391 u32 integ_len; 1392 u32 maj_stat; 1393 int status = -EIO; 1394 1395 integ_len = ntohl(*(*p)++); 1396 if (integ_len & 3) 1397 return status; 1398 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1399 mic_offset = integ_len + data_offset; 1400 if (mic_offset > rcv_buf->len) 1401 return status; 1402 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1403 return status; 1404 1405 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1406 mic_offset - data_offset)) 1407 return status; 1408 1409 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1410 return status; 1411 1412 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic); 1413 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1414 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1415 if (maj_stat != GSS_S_COMPLETE) 1416 return status; 1417 return 0; 1418 } 1419 1420 static inline int 1421 gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1422 struct rpc_rqst *rqstp, __be32 **p) 1423 { 1424 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1425 u32 offset; 1426 u32 opaque_len; 1427 u32 maj_stat; 1428 int status = -EIO; 1429 1430 opaque_len = ntohl(*(*p)++); 1431 offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1432 if (offset + opaque_len > rcv_buf->len) 1433 return status; 1434 /* remove padding: */ 1435 rcv_buf->len = offset + opaque_len; 1436 1437 maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); 1438 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1439 clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); 1440 if (maj_stat != GSS_S_COMPLETE) 1441 return status; 1442 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1443 return status; 1444 1445 return 0; 1446 } 1447 1448 1449 static int 1450 gss_unwrap_resp(struct rpc_task *task, 1451 kxdrproc_t decode, void *rqstp, __be32 *p, void *obj) 1452 { 1453 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1454 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1455 gc_base); 1456 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1457 __be32 *savedp = p; 1458 struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head; 1459 int savedlen = head->iov_len; 1460 int status = -EIO; 1461 1462 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1463 goto out_decode; 1464 switch (gss_cred->gc_service) { 1465 case RPC_GSS_SVC_NONE: 1466 break; 1467 case RPC_GSS_SVC_INTEGRITY: 1468 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1469 if (status) 1470 goto out; 1471 break; 1472 case RPC_GSS_SVC_PRIVACY: 1473 status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p); 1474 if (status) 1475 goto out; 1476 break; 1477 } 1478 /* take into account extra slack for integrity and privacy cases: */ 1479 cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp) 1480 + (savedlen - head->iov_len); 1481 out_decode: 1482 status = decode(rqstp, p, obj); 1483 out: 1484 gss_put_ctx(ctx); 1485 dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid, 1486 status); 1487 return status; 1488 } 1489 1490 static const struct rpc_authops authgss_ops = { 1491 .owner = THIS_MODULE, 1492 .au_flavor = RPC_AUTH_GSS, 1493 .au_name = "RPCSEC_GSS", 1494 .create = gss_create, 1495 .destroy = gss_destroy, 1496 .lookup_cred = gss_lookup_cred, 1497 .crcreate = gss_create_cred 1498 }; 1499 1500 static const struct rpc_credops gss_credops = { 1501 .cr_name = "AUTH_GSS", 1502 .crdestroy = gss_destroy_cred, 1503 .cr_init = gss_cred_init, 1504 .crbind = rpcauth_generic_bind_cred, 1505 .crmatch = gss_match, 1506 .crmarshal = gss_marshal, 1507 .crrefresh = gss_refresh, 1508 .crvalidate = gss_validate, 1509 .crwrap_req = gss_wrap_req, 1510 .crunwrap_resp = gss_unwrap_resp, 1511 }; 1512 1513 static const struct rpc_credops gss_nullops = { 1514 .cr_name = "AUTH_GSS", 1515 .crdestroy = gss_destroy_nullcred, 1516 .crbind = rpcauth_generic_bind_cred, 1517 .crmatch = gss_match, 1518 .crmarshal = gss_marshal, 1519 .crrefresh = gss_refresh_null, 1520 .crvalidate = gss_validate, 1521 .crwrap_req = gss_wrap_req, 1522 .crunwrap_resp = gss_unwrap_resp, 1523 }; 1524 1525 static const struct rpc_pipe_ops gss_upcall_ops_v0 = { 1526 .upcall = gss_pipe_upcall, 1527 .downcall = gss_pipe_downcall, 1528 .destroy_msg = gss_pipe_destroy_msg, 1529 .open_pipe = gss_pipe_open_v0, 1530 .release_pipe = gss_pipe_release, 1531 }; 1532 1533 static const struct rpc_pipe_ops gss_upcall_ops_v1 = { 1534 .upcall = gss_pipe_upcall, 1535 .downcall = gss_pipe_downcall, 1536 .destroy_msg = gss_pipe_destroy_msg, 1537 .open_pipe = gss_pipe_open_v1, 1538 .release_pipe = gss_pipe_release, 1539 }; 1540 1541 /* 1542 * Initialize RPCSEC_GSS module 1543 */ 1544 static int __init init_rpcsec_gss(void) 1545 { 1546 int err = 0; 1547 1548 err = rpcauth_register(&authgss_ops); 1549 if (err) 1550 goto out; 1551 err = gss_svc_init(); 1552 if (err) 1553 goto out_unregister; 1554 rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version"); 1555 return 0; 1556 out_unregister: 1557 rpcauth_unregister(&authgss_ops); 1558 out: 1559 return err; 1560 } 1561 1562 static void __exit exit_rpcsec_gss(void) 1563 { 1564 gss_svc_shutdown(); 1565 rpcauth_unregister(&authgss_ops); 1566 rcu_barrier(); /* Wait for completion of call_rcu()'s */ 1567 } 1568 1569 MODULE_LICENSE("GPL"); 1570 module_init(init_rpcsec_gss) 1571 module_exit(exit_rpcsec_gss) 1572