auth_gss.c revision f134585a7343d71f9be7f0cf97e2145f21dd10c6
1/* 2 * linux/net/sunrpc/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 * $Id$ 38 */ 39 40 41#include <linux/module.h> 42#include <linux/init.h> 43#include <linux/types.h> 44#include <linux/slab.h> 45#include <linux/sched.h> 46#include <linux/sunrpc/clnt.h> 47#include <linux/sunrpc/auth.h> 48#include <linux/sunrpc/auth_gss.h> 49#include <linux/sunrpc/svcauth_gss.h> 50#include <linux/sunrpc/gss_err.h> 51#include <linux/workqueue.h> 52#include <linux/sunrpc/rpc_pipe_fs.h> 53#include <linux/sunrpc/gss_api.h> 54#include <asm/uaccess.h> 55 56static struct rpc_authops authgss_ops; 57 58static struct rpc_credops gss_credops; 59 60#ifdef RPC_DEBUG 61# define RPCDBG_FACILITY RPCDBG_AUTH 62#endif 63 64#define NFS_NGROUPS 16 65 66#define GSS_CRED_EXPIRE (60 * HZ) /* XXX: reasonable? */ 67#define GSS_CRED_SLACK 1024 /* XXX: unused */ 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 56 71 72/* XXX this define must match the gssd define 73* as it is passed to gssd to signal the use of 74* machine creds should be part of the shared rpc interface */ 75 76#define CA_RUN_AS_MACHINE 0x00000200 77 78/* dump the buffer in `emacs-hexl' style */ 79#define isprint(c) ((c > 0x1f) && (c < 0x7f)) 80 81static DEFINE_RWLOCK(gss_ctx_lock); 82 83struct gss_auth { 84 struct rpc_auth rpc_auth; 85 struct gss_api_mech *mech; 86 enum rpc_gss_svc service; 87 struct list_head upcalls; 88 struct rpc_clnt *client; 89 struct dentry *dentry; 90 char path[48]; 91 spinlock_t lock; 92}; 93 94static void gss_destroy_ctx(struct gss_cl_ctx *); 95static struct rpc_pipe_ops gss_upcall_ops; 96 97void 98print_hexl(u32 *p, u_int length, u_int offset) 99{ 100 u_int i, j, jm; 101 u8 c, *cp; 102 103 dprintk("RPC: print_hexl: length %d\n",length); 104 dprintk("\n"); 105 cp = (u8 *) p; 106 107 for (i = 0; i < length; i += 0x10) { 108 dprintk(" %04x: ", (u_int)(i + offset)); 109 jm = length - i; 110 jm = jm > 16 ? 16 : jm; 111 112 for (j = 0; j < jm; j++) { 113 if ((j % 2) == 1) 114 dprintk("%02x ", (u_int)cp[i+j]); 115 else 116 dprintk("%02x", (u_int)cp[i+j]); 117 } 118 for (; j < 16; j++) { 119 if ((j % 2) == 1) 120 dprintk(" "); 121 else 122 dprintk(" "); 123 } 124 dprintk(" "); 125 126 for (j = 0; j < jm; j++) { 127 c = cp[i+j]; 128 c = isprint(c) ? c : '.'; 129 dprintk("%c", c); 130 } 131 dprintk("\n"); 132 } 133} 134 135EXPORT_SYMBOL(print_hexl); 136 137static inline struct gss_cl_ctx * 138gss_get_ctx(struct gss_cl_ctx *ctx) 139{ 140 atomic_inc(&ctx->count); 141 return ctx; 142} 143 144static inline void 145gss_put_ctx(struct gss_cl_ctx *ctx) 146{ 147 if (atomic_dec_and_test(&ctx->count)) 148 gss_destroy_ctx(ctx); 149} 150 151static void 152gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) 153{ 154 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 155 struct gss_cl_ctx *old; 156 write_lock(&gss_ctx_lock); 157 old = gss_cred->gc_ctx; 158 gss_cred->gc_ctx = ctx; 159 cred->cr_flags |= RPCAUTH_CRED_UPTODATE; 160 write_unlock(&gss_ctx_lock); 161 if (old) 162 gss_put_ctx(old); 163} 164 165static int 166gss_cred_is_uptodate_ctx(struct rpc_cred *cred) 167{ 168 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 169 int res = 0; 170 171 read_lock(&gss_ctx_lock); 172 if ((cred->cr_flags & RPCAUTH_CRED_UPTODATE) && gss_cred->gc_ctx) 173 res = 1; 174 read_unlock(&gss_ctx_lock); 175 return res; 176} 177 178static const void * 179simple_get_bytes(const void *p, const void *end, void *res, size_t len) 180{ 181 const void *q = (const void *)((const char *)p + len); 182 if (unlikely(q > end || q < p)) 183 return ERR_PTR(-EFAULT); 184 memcpy(res, p, len); 185 return q; 186} 187 188static inline const void * 189simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) 190{ 191 const void *q; 192 unsigned int len; 193 194 p = simple_get_bytes(p, end, &len, sizeof(len)); 195 if (IS_ERR(p)) 196 return p; 197 q = (const void *)((const char *)p + len); 198 if (unlikely(q > end || q < p)) 199 return ERR_PTR(-EFAULT); 200 dest->data = kmalloc(len, GFP_KERNEL); 201 if (unlikely(dest->data == NULL)) 202 return ERR_PTR(-ENOMEM); 203 dest->len = len; 204 memcpy(dest->data, p, len); 205 return q; 206} 207 208static struct gss_cl_ctx * 209gss_cred_get_ctx(struct rpc_cred *cred) 210{ 211 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 212 struct gss_cl_ctx *ctx = NULL; 213 214 read_lock(&gss_ctx_lock); 215 if (gss_cred->gc_ctx) 216 ctx = gss_get_ctx(gss_cred->gc_ctx); 217 read_unlock(&gss_ctx_lock); 218 return ctx; 219} 220 221static struct gss_cl_ctx * 222gss_alloc_context(void) 223{ 224 struct gss_cl_ctx *ctx; 225 226 ctx = kmalloc(sizeof(*ctx), GFP_KERNEL); 227 if (ctx != NULL) { 228 memset(ctx, 0, sizeof(*ctx)); 229 ctx->gc_proc = RPC_GSS_PROC_DATA; 230 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ 231 spin_lock_init(&ctx->gc_seq_lock); 232 atomic_set(&ctx->count,1); 233 } 234 return ctx; 235} 236 237#define GSSD_MIN_TIMEOUT (60 * 60) 238static const void * 239gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) 240{ 241 const void *q; 242 unsigned int seclen; 243 unsigned int timeout; 244 u32 window_size; 245 int ret; 246 247 /* First unsigned int gives the lifetime (in seconds) of the cred */ 248 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 249 if (IS_ERR(p)) 250 goto err; 251 if (timeout == 0) 252 timeout = GSSD_MIN_TIMEOUT; 253 ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4; 254 /* Sequence number window. Determines the maximum number of simultaneous requests */ 255 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 256 if (IS_ERR(p)) 257 goto err; 258 ctx->gc_win = window_size; 259 /* gssd signals an error by passing ctx->gc_win = 0: */ 260 if (ctx->gc_win == 0) { 261 /* in which case, p points to an error code which we ignore */ 262 p = ERR_PTR(-EACCES); 263 goto err; 264 } 265 /* copy the opaque wire context */ 266 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 267 if (IS_ERR(p)) 268 goto err; 269 /* import the opaque security context */ 270 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 271 if (IS_ERR(p)) 272 goto err; 273 q = (const void *)((const char *)p + seclen); 274 if (unlikely(q > end || q < p)) { 275 p = ERR_PTR(-EFAULT); 276 goto err; 277 } 278 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx); 279 if (ret < 0) { 280 p = ERR_PTR(ret); 281 goto err; 282 } 283 return q; 284err: 285 dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p)); 286 return p; 287} 288 289 290struct gss_upcall_msg { 291 atomic_t count; 292 uid_t uid; 293 struct rpc_pipe_msg msg; 294 struct list_head list; 295 struct gss_auth *auth; 296 struct rpc_wait_queue rpc_waitqueue; 297 wait_queue_head_t waitqueue; 298 struct gss_cl_ctx *ctx; 299}; 300 301static void 302gss_release_msg(struct gss_upcall_msg *gss_msg) 303{ 304 if (!atomic_dec_and_test(&gss_msg->count)) 305 return; 306 BUG_ON(!list_empty(&gss_msg->list)); 307 if (gss_msg->ctx != NULL) 308 gss_put_ctx(gss_msg->ctx); 309 kfree(gss_msg); 310} 311 312static struct gss_upcall_msg * 313__gss_find_upcall(struct gss_auth *gss_auth, uid_t uid) 314{ 315 struct gss_upcall_msg *pos; 316 list_for_each_entry(pos, &gss_auth->upcalls, list) { 317 if (pos->uid != uid) 318 continue; 319 atomic_inc(&pos->count); 320 dprintk("RPC: gss_find_upcall found msg %p\n", pos); 321 return pos; 322 } 323 dprintk("RPC: gss_find_upcall found nothing\n"); 324 return NULL; 325} 326 327/* Try to add a upcall to the pipefs queue. 328 * If an upcall owned by our uid already exists, then we return a reference 329 * to that upcall instead of adding the new upcall. 330 */ 331static inline struct gss_upcall_msg * 332gss_add_msg(struct gss_auth *gss_auth, struct gss_upcall_msg *gss_msg) 333{ 334 struct gss_upcall_msg *old; 335 336 spin_lock(&gss_auth->lock); 337 old = __gss_find_upcall(gss_auth, gss_msg->uid); 338 if (old == NULL) { 339 atomic_inc(&gss_msg->count); 340 list_add(&gss_msg->list, &gss_auth->upcalls); 341 } else 342 gss_msg = old; 343 spin_unlock(&gss_auth->lock); 344 return gss_msg; 345} 346 347static void 348__gss_unhash_msg(struct gss_upcall_msg *gss_msg) 349{ 350 if (list_empty(&gss_msg->list)) 351 return; 352 list_del_init(&gss_msg->list); 353 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 354 wake_up_all(&gss_msg->waitqueue); 355 atomic_dec(&gss_msg->count); 356} 357 358static void 359gss_unhash_msg(struct gss_upcall_msg *gss_msg) 360{ 361 struct gss_auth *gss_auth = gss_msg->auth; 362 363 spin_lock(&gss_auth->lock); 364 __gss_unhash_msg(gss_msg); 365 spin_unlock(&gss_auth->lock); 366} 367 368static void 369gss_upcall_callback(struct rpc_task *task) 370{ 371 struct gss_cred *gss_cred = container_of(task->tk_msg.rpc_cred, 372 struct gss_cred, gc_base); 373 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 374 375 BUG_ON(gss_msg == NULL); 376 if (gss_msg->ctx) 377 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_get_ctx(gss_msg->ctx)); 378 else 379 task->tk_status = gss_msg->msg.errno; 380 spin_lock(&gss_msg->auth->lock); 381 gss_cred->gc_upcall = NULL; 382 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 383 spin_unlock(&gss_msg->auth->lock); 384 gss_release_msg(gss_msg); 385} 386 387static inline struct gss_upcall_msg * 388gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid) 389{ 390 struct gss_upcall_msg *gss_msg; 391 392 gss_msg = kmalloc(sizeof(*gss_msg), GFP_KERNEL); 393 if (gss_msg != NULL) { 394 memset(gss_msg, 0, sizeof(*gss_msg)); 395 INIT_LIST_HEAD(&gss_msg->list); 396 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 397 init_waitqueue_head(&gss_msg->waitqueue); 398 atomic_set(&gss_msg->count, 1); 399 gss_msg->msg.data = &gss_msg->uid; 400 gss_msg->msg.len = sizeof(gss_msg->uid); 401 gss_msg->uid = uid; 402 gss_msg->auth = gss_auth; 403 } 404 return gss_msg; 405} 406 407static struct gss_upcall_msg * 408gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 409{ 410 struct gss_upcall_msg *gss_new, *gss_msg; 411 412 gss_new = gss_alloc_msg(gss_auth, cred->cr_uid); 413 if (gss_new == NULL) 414 return ERR_PTR(-ENOMEM); 415 gss_msg = gss_add_msg(gss_auth, gss_new); 416 if (gss_msg == gss_new) { 417 int res = rpc_queue_upcall(gss_auth->dentry->d_inode, &gss_new->msg); 418 if (res) { 419 gss_unhash_msg(gss_new); 420 gss_msg = ERR_PTR(res); 421 } 422 } else 423 gss_release_msg(gss_new); 424 return gss_msg; 425} 426 427static inline int 428gss_refresh_upcall(struct rpc_task *task) 429{ 430 struct rpc_cred *cred = task->tk_msg.rpc_cred; 431 struct gss_auth *gss_auth = container_of(task->tk_client->cl_auth, 432 struct gss_auth, rpc_auth); 433 struct gss_cred *gss_cred = container_of(cred, 434 struct gss_cred, gc_base); 435 struct gss_upcall_msg *gss_msg; 436 int err = 0; 437 438 dprintk("RPC: %4u gss_refresh_upcall for uid %u\n", task->tk_pid, cred->cr_uid); 439 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 440 if (IS_ERR(gss_msg)) { 441 err = PTR_ERR(gss_msg); 442 goto out; 443 } 444 spin_lock(&gss_auth->lock); 445 if (gss_cred->gc_upcall != NULL) 446 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL, NULL); 447 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { 448 task->tk_timeout = 0; 449 gss_cred->gc_upcall = gss_msg; 450 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 451 atomic_inc(&gss_msg->count); 452 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback, NULL); 453 } else 454 err = gss_msg->msg.errno; 455 spin_unlock(&gss_auth->lock); 456 gss_release_msg(gss_msg); 457out: 458 dprintk("RPC: %4u gss_refresh_upcall for uid %u result %d\n", task->tk_pid, 459 cred->cr_uid, err); 460 return err; 461} 462 463static inline int 464gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 465{ 466 struct rpc_cred *cred = &gss_cred->gc_base; 467 struct gss_upcall_msg *gss_msg; 468 DEFINE_WAIT(wait); 469 int err = 0; 470 471 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); 472 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 473 if (IS_ERR(gss_msg)) { 474 err = PTR_ERR(gss_msg); 475 goto out; 476 } 477 for (;;) { 478 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); 479 spin_lock(&gss_auth->lock); 480 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 481 spin_unlock(&gss_auth->lock); 482 break; 483 } 484 spin_unlock(&gss_auth->lock); 485 if (signalled()) { 486 err = -ERESTARTSYS; 487 goto out_intr; 488 } 489 schedule(); 490 } 491 if (gss_msg->ctx) 492 gss_cred_set_ctx(cred, gss_get_ctx(gss_msg->ctx)); 493 else 494 err = gss_msg->msg.errno; 495out_intr: 496 finish_wait(&gss_msg->waitqueue, &wait); 497 gss_release_msg(gss_msg); 498out: 499 dprintk("RPC: gss_create_upcall for uid %u result %d\n", cred->cr_uid, err); 500 return err; 501} 502 503static ssize_t 504gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, 505 char __user *dst, size_t buflen) 506{ 507 char *data = (char *)msg->data + msg->copied; 508 ssize_t mlen = msg->len; 509 ssize_t left; 510 511 if (mlen > buflen) 512 mlen = buflen; 513 left = copy_to_user(dst, data, mlen); 514 if (left < 0) { 515 msg->errno = left; 516 return left; 517 } 518 mlen -= left; 519 msg->copied += mlen; 520 msg->errno = 0; 521 return mlen; 522} 523 524#define MSG_BUF_MAXSIZE 1024 525 526static ssize_t 527gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 528{ 529 const void *p, *end; 530 void *buf; 531 struct rpc_clnt *clnt; 532 struct gss_auth *gss_auth; 533 struct rpc_cred *cred; 534 struct gss_upcall_msg *gss_msg; 535 struct gss_cl_ctx *ctx; 536 uid_t uid; 537 int err = -EFBIG; 538 539 if (mlen > MSG_BUF_MAXSIZE) 540 goto out; 541 err = -ENOMEM; 542 buf = kmalloc(mlen, GFP_KERNEL); 543 if (!buf) 544 goto out; 545 546 clnt = RPC_I(filp->f_dentry->d_inode)->private; 547 err = -EFAULT; 548 if (copy_from_user(buf, src, mlen)) 549 goto err; 550 551 end = (const void *)((char *)buf + mlen); 552 p = simple_get_bytes(buf, end, &uid, sizeof(uid)); 553 if (IS_ERR(p)) { 554 err = PTR_ERR(p); 555 goto err; 556 } 557 558 err = -ENOMEM; 559 ctx = gss_alloc_context(); 560 if (ctx == NULL) 561 goto err; 562 err = 0; 563 gss_auth = container_of(clnt->cl_auth, struct gss_auth, rpc_auth); 564 p = gss_fill_context(p, end, ctx, gss_auth->mech); 565 if (IS_ERR(p)) { 566 err = PTR_ERR(p); 567 if (err != -EACCES) 568 goto err_put_ctx; 569 } 570 spin_lock(&gss_auth->lock); 571 gss_msg = __gss_find_upcall(gss_auth, uid); 572 if (gss_msg) { 573 if (err == 0 && gss_msg->ctx == NULL) 574 gss_msg->ctx = gss_get_ctx(ctx); 575 gss_msg->msg.errno = err; 576 __gss_unhash_msg(gss_msg); 577 spin_unlock(&gss_auth->lock); 578 gss_release_msg(gss_msg); 579 } else { 580 struct auth_cred acred = { .uid = uid }; 581 spin_unlock(&gss_auth->lock); 582 cred = rpcauth_lookup_credcache(clnt->cl_auth, &acred, 0); 583 if (IS_ERR(cred)) { 584 err = PTR_ERR(cred); 585 goto err_put_ctx; 586 } 587 gss_cred_set_ctx(cred, gss_get_ctx(ctx)); 588 } 589 gss_put_ctx(ctx); 590 kfree(buf); 591 dprintk("RPC: gss_pipe_downcall returning length %Zu\n", mlen); 592 return mlen; 593err_put_ctx: 594 gss_put_ctx(ctx); 595err: 596 kfree(buf); 597out: 598 dprintk("RPC: gss_pipe_downcall returning %d\n", err); 599 return err; 600} 601 602static void 603gss_pipe_release(struct inode *inode) 604{ 605 struct rpc_inode *rpci = RPC_I(inode); 606 struct rpc_clnt *clnt; 607 struct rpc_auth *auth; 608 struct gss_auth *gss_auth; 609 610 clnt = rpci->private; 611 auth = clnt->cl_auth; 612 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 613 spin_lock(&gss_auth->lock); 614 while (!list_empty(&gss_auth->upcalls)) { 615 struct gss_upcall_msg *gss_msg; 616 617 gss_msg = list_entry(gss_auth->upcalls.next, 618 struct gss_upcall_msg, list); 619 gss_msg->msg.errno = -EPIPE; 620 atomic_inc(&gss_msg->count); 621 __gss_unhash_msg(gss_msg); 622 spin_unlock(&gss_auth->lock); 623 gss_release_msg(gss_msg); 624 spin_lock(&gss_auth->lock); 625 } 626 spin_unlock(&gss_auth->lock); 627} 628 629static void 630gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 631{ 632 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 633 static unsigned long ratelimit; 634 635 if (msg->errno < 0) { 636 dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n", 637 gss_msg); 638 atomic_inc(&gss_msg->count); 639 gss_unhash_msg(gss_msg); 640 if (msg->errno == -ETIMEDOUT || msg->errno == -EPIPE) { 641 unsigned long now = jiffies; 642 if (time_after(now, ratelimit)) { 643 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 644 "Please check user daemon is running!\n"); 645 ratelimit = now + 15*HZ; 646 } 647 } 648 gss_release_msg(gss_msg); 649 } 650} 651 652/* 653 * NOTE: we have the opportunity to use different 654 * parameters based on the input flavor (which must be a pseudoflavor) 655 */ 656static struct rpc_auth * 657gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 658{ 659 struct gss_auth *gss_auth; 660 struct rpc_auth * auth; 661 int err = -ENOMEM; /* XXX? */ 662 663 dprintk("RPC: creating GSS authenticator for client %p\n",clnt); 664 665 if (!try_module_get(THIS_MODULE)) 666 return ERR_PTR(err); 667 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 668 goto out_dec; 669 gss_auth->client = clnt; 670 err = -EINVAL; 671 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 672 if (!gss_auth->mech) { 673 printk(KERN_WARNING "%s: Pseudoflavor %d not found!", 674 __FUNCTION__, flavor); 675 goto err_free; 676 } 677 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 678 if (gss_auth->service == 0) 679 goto err_put_mech; 680 INIT_LIST_HEAD(&gss_auth->upcalls); 681 spin_lock_init(&gss_auth->lock); 682 auth = &gss_auth->rpc_auth; 683 auth->au_cslack = GSS_CRED_SLACK >> 2; 684 auth->au_rslack = GSS_VERF_SLACK >> 2; 685 auth->au_ops = &authgss_ops; 686 auth->au_flavor = flavor; 687 atomic_set(&auth->au_count, 1); 688 689 err = rpcauth_init_credcache(auth, GSS_CRED_EXPIRE); 690 if (err) 691 goto err_put_mech; 692 693 snprintf(gss_auth->path, sizeof(gss_auth->path), "%s/%s", 694 clnt->cl_pathname, 695 gss_auth->mech->gm_name); 696 gss_auth->dentry = rpc_mkpipe(gss_auth->path, clnt, &gss_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN); 697 if (IS_ERR(gss_auth->dentry)) { 698 err = PTR_ERR(gss_auth->dentry); 699 goto err_put_mech; 700 } 701 702 return auth; 703err_put_mech: 704 gss_mech_put(gss_auth->mech); 705err_free: 706 kfree(gss_auth); 707out_dec: 708 module_put(THIS_MODULE); 709 return ERR_PTR(err); 710} 711 712static void 713gss_destroy(struct rpc_auth *auth) 714{ 715 struct gss_auth *gss_auth; 716 717 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 718 auth, auth->au_flavor); 719 720 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 721 rpc_unlink(gss_auth->path); 722 gss_mech_put(gss_auth->mech); 723 724 rpcauth_free_credcache(auth); 725 kfree(gss_auth); 726 module_put(THIS_MODULE); 727} 728 729/* gss_destroy_cred (and gss_destroy_ctx) are used to clean up after failure 730 * to create a new cred or context, so they check that things have been 731 * allocated before freeing them. */ 732static void 733gss_destroy_ctx(struct gss_cl_ctx *ctx) 734{ 735 dprintk("RPC: gss_destroy_ctx\n"); 736 737 if (ctx->gc_gss_ctx) 738 gss_delete_sec_context(&ctx->gc_gss_ctx); 739 740 kfree(ctx->gc_wire_ctx.data); 741 kfree(ctx); 742} 743 744static void 745gss_destroy_cred(struct rpc_cred *rc) 746{ 747 struct gss_cred *cred = container_of(rc, struct gss_cred, gc_base); 748 749 dprintk("RPC: gss_destroy_cred \n"); 750 751 if (cred->gc_ctx) 752 gss_put_ctx(cred->gc_ctx); 753 kfree(cred); 754} 755 756/* 757 * Lookup RPCSEC_GSS cred for the current process 758 */ 759static struct rpc_cred * 760gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int taskflags) 761{ 762 return rpcauth_lookup_credcache(auth, acred, taskflags); 763} 764 765static struct rpc_cred * 766gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int taskflags) 767{ 768 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 769 struct gss_cred *cred = NULL; 770 int err = -ENOMEM; 771 772 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 773 acred->uid, auth->au_flavor); 774 775 if (!(cred = kmalloc(sizeof(*cred), GFP_KERNEL))) 776 goto out_err; 777 778 memset(cred, 0, sizeof(*cred)); 779 atomic_set(&cred->gc_count, 1); 780 cred->gc_uid = acred->uid; 781 /* 782 * Note: in order to force a call to call_refresh(), we deliberately 783 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 784 */ 785 cred->gc_flags = 0; 786 cred->gc_base.cr_ops = &gss_credops; 787 cred->gc_service = gss_auth->service; 788 err = gss_create_upcall(gss_auth, cred); 789 if (err < 0) 790 goto out_err; 791 792 return &cred->gc_base; 793 794out_err: 795 dprintk("RPC: gss_create_cred failed with error %d\n", err); 796 if (cred) gss_destroy_cred(&cred->gc_base); 797 return ERR_PTR(err); 798} 799 800static int 801gss_match(struct auth_cred *acred, struct rpc_cred *rc, int taskflags) 802{ 803 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 804 805 /* Don't match with creds that have expired. */ 806 if (gss_cred->gc_ctx && time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 807 return 0; 808 return (rc->cr_uid == acred->uid); 809} 810 811/* 812* Marshal credentials. 813* Maybe we should keep a cached credential for performance reasons. 814*/ 815static u32 * 816gss_marshal(struct rpc_task *task, u32 *p) 817{ 818 struct rpc_cred *cred = task->tk_msg.rpc_cred; 819 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 820 gc_base); 821 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 822 u32 *cred_len; 823 struct rpc_rqst *req = task->tk_rqstp; 824 u32 maj_stat = 0; 825 struct xdr_netobj mic; 826 struct kvec iov; 827 struct xdr_buf verf_buf; 828 829 dprintk("RPC: %4u gss_marshal\n", task->tk_pid); 830 831 *p++ = htonl(RPC_AUTH_GSS); 832 cred_len = p++; 833 834 spin_lock(&ctx->gc_seq_lock); 835 req->rq_seqno = ctx->gc_seq++; 836 spin_unlock(&ctx->gc_seq_lock); 837 838 *p++ = htonl((u32) RPC_GSS_VERSION); 839 *p++ = htonl((u32) ctx->gc_proc); 840 *p++ = htonl((u32) req->rq_seqno); 841 *p++ = htonl((u32) gss_cred->gc_service); 842 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 843 *cred_len = htonl((p - (cred_len + 1)) << 2); 844 845 /* We compute the checksum for the verifier over the xdr-encoded bytes 846 * starting with the xid and ending at the end of the credential: */ 847 iov.iov_base = xprt_skip_transport_header(task->tk_xprt, 848 req->rq_snd_buf.head[0].iov_base); 849 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 850 xdr_buf_from_iov(&iov, &verf_buf); 851 852 /* set verifier flavor*/ 853 *p++ = htonl(RPC_AUTH_GSS); 854 855 mic.data = (u8 *)(p + 1); 856 maj_stat = gss_get_mic(ctx->gc_gss_ctx, 857 GSS_C_QOP_DEFAULT, 858 &verf_buf, &mic); 859 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 860 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 861 } else if (maj_stat != 0) { 862 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 863 goto out_put_ctx; 864 } 865 p = xdr_encode_opaque(p, NULL, mic.len); 866 gss_put_ctx(ctx); 867 return p; 868out_put_ctx: 869 gss_put_ctx(ctx); 870 return NULL; 871} 872 873/* 874* Refresh credentials. XXX - finish 875*/ 876static int 877gss_refresh(struct rpc_task *task) 878{ 879 880 if (!gss_cred_is_uptodate_ctx(task->tk_msg.rpc_cred)) 881 return gss_refresh_upcall(task); 882 return 0; 883} 884 885static u32 * 886gss_validate(struct rpc_task *task, u32 *p) 887{ 888 struct rpc_cred *cred = task->tk_msg.rpc_cred; 889 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 890 gc_base); 891 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 892 u32 seq, qop_state; 893 struct kvec iov; 894 struct xdr_buf verf_buf; 895 struct xdr_netobj mic; 896 u32 flav,len; 897 u32 maj_stat; 898 899 dprintk("RPC: %4u gss_validate\n", task->tk_pid); 900 901 flav = ntohl(*p++); 902 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 903 goto out_bad; 904 if (flav != RPC_AUTH_GSS) 905 goto out_bad; 906 seq = htonl(task->tk_rqstp->rq_seqno); 907 iov.iov_base = &seq; 908 iov.iov_len = sizeof(seq); 909 xdr_buf_from_iov(&iov, &verf_buf); 910 mic.data = (u8 *)p; 911 mic.len = len; 912 913 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic, &qop_state); 914 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 915 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 916 if (maj_stat) 917 goto out_bad; 918 switch (gss_cred->gc_service) { 919 case RPC_GSS_SVC_NONE: 920 /* verifier data, flavor, length: */ 921 task->tk_auth->au_rslack = XDR_QUADLEN(len) + 2; 922 break; 923 case RPC_GSS_SVC_INTEGRITY: 924 /* verifier data, flavor, length, length, sequence number: */ 925 task->tk_auth->au_rslack = XDR_QUADLEN(len) + 4; 926 break; 927 case RPC_GSS_SVC_PRIVACY: 928 goto out_bad; 929 } 930 gss_put_ctx(ctx); 931 dprintk("RPC: %4u GSS gss_validate: gss_verify_mic succeeded.\n", 932 task->tk_pid); 933 return p + XDR_QUADLEN(len); 934out_bad: 935 gss_put_ctx(ctx); 936 dprintk("RPC: %4u gss_validate failed.\n", task->tk_pid); 937 return NULL; 938} 939 940static inline int 941gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 942 kxdrproc_t encode, struct rpc_rqst *rqstp, u32 *p, void *obj) 943{ 944 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 945 struct xdr_buf integ_buf; 946 u32 *integ_len = NULL; 947 struct xdr_netobj mic; 948 u32 offset, *q; 949 struct kvec *iov; 950 u32 maj_stat = 0; 951 int status = -EIO; 952 953 integ_len = p++; 954 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 955 *p++ = htonl(rqstp->rq_seqno); 956 957 status = encode(rqstp, p, obj); 958 if (status) 959 return status; 960 961 if (xdr_buf_subsegment(snd_buf, &integ_buf, 962 offset, snd_buf->len - offset)) 963 return status; 964 *integ_len = htonl(integ_buf.len); 965 966 /* guess whether we're in the head or the tail: */ 967 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 968 iov = snd_buf->tail; 969 else 970 iov = snd_buf->head; 971 p = iov->iov_base + iov->iov_len; 972 mic.data = (u8 *)(p + 1); 973 974 maj_stat = gss_get_mic(ctx->gc_gss_ctx, 975 GSS_C_QOP_DEFAULT, &integ_buf, &mic); 976 status = -EIO; /* XXX? */ 977 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 978 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 979 else if (maj_stat) 980 return status; 981 q = xdr_encode_opaque(p, NULL, mic.len); 982 983 offset = (u8 *)q - (u8 *)p; 984 iov->iov_len += offset; 985 snd_buf->len += offset; 986 return 0; 987} 988 989static int 990gss_wrap_req(struct rpc_task *task, 991 kxdrproc_t encode, void *rqstp, u32 *p, void *obj) 992{ 993 struct rpc_cred *cred = task->tk_msg.rpc_cred; 994 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 995 gc_base); 996 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 997 int status = -EIO; 998 999 dprintk("RPC: %4u gss_wrap_req\n", task->tk_pid); 1000 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1001 /* The spec seems a little ambiguous here, but I think that not 1002 * wrapping context destruction requests makes the most sense. 1003 */ 1004 status = encode(rqstp, p, obj); 1005 goto out; 1006 } 1007 switch (gss_cred->gc_service) { 1008 case RPC_GSS_SVC_NONE: 1009 status = encode(rqstp, p, obj); 1010 break; 1011 case RPC_GSS_SVC_INTEGRITY: 1012 status = gss_wrap_req_integ(cred, ctx, encode, 1013 rqstp, p, obj); 1014 break; 1015 case RPC_GSS_SVC_PRIVACY: 1016 break; 1017 } 1018out: 1019 gss_put_ctx(ctx); 1020 dprintk("RPC: %4u gss_wrap_req returning %d\n", task->tk_pid, status); 1021 return status; 1022} 1023 1024static inline int 1025gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1026 struct rpc_rqst *rqstp, u32 **p) 1027{ 1028 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1029 struct xdr_buf integ_buf; 1030 struct xdr_netobj mic; 1031 u32 data_offset, mic_offset; 1032 u32 integ_len; 1033 u32 maj_stat; 1034 int status = -EIO; 1035 1036 integ_len = ntohl(*(*p)++); 1037 if (integ_len & 3) 1038 return status; 1039 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1040 mic_offset = integ_len + data_offset; 1041 if (mic_offset > rcv_buf->len) 1042 return status; 1043 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1044 return status; 1045 1046 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1047 mic_offset - data_offset)) 1048 return status; 1049 1050 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1051 return status; 1052 1053 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, 1054 &mic, NULL); 1055 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1056 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 1057 if (maj_stat != GSS_S_COMPLETE) 1058 return status; 1059 return 0; 1060} 1061 1062static int 1063gss_unwrap_resp(struct rpc_task *task, 1064 kxdrproc_t decode, void *rqstp, u32 *p, void *obj) 1065{ 1066 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1067 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1068 gc_base); 1069 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1070 int status = -EIO; 1071 1072 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1073 goto out_decode; 1074 switch (gss_cred->gc_service) { 1075 case RPC_GSS_SVC_NONE: 1076 break; 1077 case RPC_GSS_SVC_INTEGRITY: 1078 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1079 if (status) 1080 goto out; 1081 break; 1082 case RPC_GSS_SVC_PRIVACY: 1083 break; 1084 } 1085out_decode: 1086 status = decode(rqstp, p, obj); 1087out: 1088 gss_put_ctx(ctx); 1089 dprintk("RPC: %4u gss_unwrap_resp returning %d\n", task->tk_pid, 1090 status); 1091 return status; 1092} 1093 1094static struct rpc_authops authgss_ops = { 1095 .owner = THIS_MODULE, 1096 .au_flavor = RPC_AUTH_GSS, 1097#ifdef RPC_DEBUG 1098 .au_name = "RPCSEC_GSS", 1099#endif 1100 .create = gss_create, 1101 .destroy = gss_destroy, 1102 .lookup_cred = gss_lookup_cred, 1103 .crcreate = gss_create_cred 1104}; 1105 1106static struct rpc_credops gss_credops = { 1107 .cr_name = "AUTH_GSS", 1108 .crdestroy = gss_destroy_cred, 1109 .crmatch = gss_match, 1110 .crmarshal = gss_marshal, 1111 .crrefresh = gss_refresh, 1112 .crvalidate = gss_validate, 1113 .crwrap_req = gss_wrap_req, 1114 .crunwrap_resp = gss_unwrap_resp, 1115}; 1116 1117static struct rpc_pipe_ops gss_upcall_ops = { 1118 .upcall = gss_pipe_upcall, 1119 .downcall = gss_pipe_downcall, 1120 .destroy_msg = gss_pipe_destroy_msg, 1121 .release_pipe = gss_pipe_release, 1122}; 1123 1124/* 1125 * Initialize RPCSEC_GSS module 1126 */ 1127static int __init init_rpcsec_gss(void) 1128{ 1129 int err = 0; 1130 1131 err = rpcauth_register(&authgss_ops); 1132 if (err) 1133 goto out; 1134 err = gss_svc_init(); 1135 if (err) 1136 goto out_unregister; 1137 return 0; 1138out_unregister: 1139 rpcauth_unregister(&authgss_ops); 1140out: 1141 return err; 1142} 1143 1144static void __exit exit_rpcsec_gss(void) 1145{ 1146 gss_svc_shutdown(); 1147 rpcauth_unregister(&authgss_ops); 1148} 1149 1150MODULE_LICENSE("GPL"); 1151module_init(init_rpcsec_gss) 1152module_exit(exit_rpcsec_gss) 1153