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/socket.h> 46 #include <linux/in.h> 47 #include <linux/sched.h> 48 #include <linux/sunrpc/clnt.h> 49 #include <linux/sunrpc/auth.h> 50 #include <linux/sunrpc/auth_gss.h> 51 #include <linux/sunrpc/svcauth_gss.h> 52 #include <linux/sunrpc/gss_err.h> 53 #include <linux/workqueue.h> 54 #include <linux/sunrpc/rpc_pipe_fs.h> 55 #include <linux/sunrpc/gss_api.h> 56 #include <asm/uaccess.h> 57 58 static struct rpc_authops authgss_ops; 59 60 static struct rpc_credops gss_credops; 61 62 #ifdef RPC_DEBUG 63 # define RPCDBG_FACILITY RPCDBG_AUTH 64 #endif 65 66 #define NFS_NGROUPS 16 67 68 #define GSS_CRED_EXPIRE (60 * HZ) /* XXX: reasonable? */ 69 #define GSS_CRED_SLACK 1024 /* XXX: unused */ 70 /* length of a krb5 verifier (48), plus data added before arguments when 71 * using integrity (two 4-byte integers): */ 72 #define GSS_VERF_SLACK 56 73 74 /* XXX this define must match the gssd define 75 * as it is passed to gssd to signal the use of 76 * machine creds should be part of the shared rpc interface */ 77 78 #define CA_RUN_AS_MACHINE 0x00000200 79 80 /* dump the buffer in `emacs-hexl' style */ 81 #define isprint(c) ((c > 0x1f) && (c < 0x7f)) 82 83 static DEFINE_RWLOCK(gss_ctx_lock); 84 85 struct gss_auth { 86 struct rpc_auth rpc_auth; 87 struct gss_api_mech *mech; 88 enum rpc_gss_svc service; 89 struct list_head upcalls; 90 struct rpc_clnt *client; 91 struct dentry *dentry; 92 char path[48]; 93 spinlock_t lock; 94 }; 95 96 static void gss_destroy_ctx(struct gss_cl_ctx *); 97 static struct rpc_pipe_ops gss_upcall_ops; 98 99 void 100 print_hexl(u32 *p, u_int length, u_int offset) 101 { 102 u_int i, j, jm; 103 u8 c, *cp; 104 105 dprintk("RPC: print_hexl: length %d\n",length); 106 dprintk("\n"); 107 cp = (u8 *) p; 108 109 for (i = 0; i < length; i += 0x10) { 110 dprintk(" %04x: ", (u_int)(i + offset)); 111 jm = length - i; 112 jm = jm > 16 ? 16 : jm; 113 114 for (j = 0; j < jm; j++) { 115 if ((j % 2) == 1) 116 dprintk("%02x ", (u_int)cp[i+j]); 117 else 118 dprintk("%02x", (u_int)cp[i+j]); 119 } 120 for (; j < 16; j++) { 121 if ((j % 2) == 1) 122 dprintk(" "); 123 else 124 dprintk(" "); 125 } 126 dprintk(" "); 127 128 for (j = 0; j < jm; j++) { 129 c = cp[i+j]; 130 c = isprint(c) ? c : '.'; 131 dprintk("%c", c); 132 } 133 dprintk("\n"); 134 } 135 } 136 137 EXPORT_SYMBOL(print_hexl); 138 139 static inline struct gss_cl_ctx * 140 gss_get_ctx(struct gss_cl_ctx *ctx) 141 { 142 atomic_inc(&ctx->count); 143 return ctx; 144 } 145 146 static inline void 147 gss_put_ctx(struct gss_cl_ctx *ctx) 148 { 149 if (atomic_dec_and_test(&ctx->count)) 150 gss_destroy_ctx(ctx); 151 } 152 153 static void 154 gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx) 155 { 156 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 157 struct gss_cl_ctx *old; 158 write_lock(&gss_ctx_lock); 159 old = gss_cred->gc_ctx; 160 gss_cred->gc_ctx = ctx; 161 cred->cr_flags |= RPCAUTH_CRED_UPTODATE; 162 write_unlock(&gss_ctx_lock); 163 if (old) 164 gss_put_ctx(old); 165 } 166 167 static int 168 gss_cred_is_uptodate_ctx(struct rpc_cred *cred) 169 { 170 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 171 int res = 0; 172 173 read_lock(&gss_ctx_lock); 174 if ((cred->cr_flags & RPCAUTH_CRED_UPTODATE) && gss_cred->gc_ctx) 175 res = 1; 176 read_unlock(&gss_ctx_lock); 177 return res; 178 } 179 180 static const void * 181 simple_get_bytes(const void *p, const void *end, void *res, size_t len) 182 { 183 const void *q = (const void *)((const char *)p + len); 184 if (unlikely(q > end || q < p)) 185 return ERR_PTR(-EFAULT); 186 memcpy(res, p, len); 187 return q; 188 } 189 190 static inline const void * 191 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest) 192 { 193 const void *q; 194 unsigned int len; 195 196 p = simple_get_bytes(p, end, &len, sizeof(len)); 197 if (IS_ERR(p)) 198 return p; 199 q = (const void *)((const char *)p + len); 200 if (unlikely(q > end || q < p)) 201 return ERR_PTR(-EFAULT); 202 dest->data = kmalloc(len, GFP_KERNEL); 203 if (unlikely(dest->data == NULL)) 204 return ERR_PTR(-ENOMEM); 205 dest->len = len; 206 memcpy(dest->data, p, len); 207 return q; 208 } 209 210 static struct gss_cl_ctx * 211 gss_cred_get_ctx(struct rpc_cred *cred) 212 { 213 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base); 214 struct gss_cl_ctx *ctx = NULL; 215 216 read_lock(&gss_ctx_lock); 217 if (gss_cred->gc_ctx) 218 ctx = gss_get_ctx(gss_cred->gc_ctx); 219 read_unlock(&gss_ctx_lock); 220 return ctx; 221 } 222 223 static struct gss_cl_ctx * 224 gss_alloc_context(void) 225 { 226 struct gss_cl_ctx *ctx; 227 228 ctx = kmalloc(sizeof(*ctx), GFP_KERNEL); 229 if (ctx != NULL) { 230 memset(ctx, 0, sizeof(*ctx)); 231 ctx->gc_proc = RPC_GSS_PROC_DATA; 232 ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ 233 spin_lock_init(&ctx->gc_seq_lock); 234 atomic_set(&ctx->count,1); 235 } 236 return ctx; 237 } 238 239 #define GSSD_MIN_TIMEOUT (60 * 60) 240 static const void * 241 gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm) 242 { 243 const void *q; 244 unsigned int seclen; 245 unsigned int timeout; 246 u32 window_size; 247 int ret; 248 249 /* First unsigned int gives the lifetime (in seconds) of the cred */ 250 p = simple_get_bytes(p, end, &timeout, sizeof(timeout)); 251 if (IS_ERR(p)) 252 goto err; 253 if (timeout == 0) 254 timeout = GSSD_MIN_TIMEOUT; 255 ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4; 256 /* Sequence number window. Determines the maximum number of simultaneous requests */ 257 p = simple_get_bytes(p, end, &window_size, sizeof(window_size)); 258 if (IS_ERR(p)) 259 goto err; 260 ctx->gc_win = window_size; 261 /* gssd signals an error by passing ctx->gc_win = 0: */ 262 if (ctx->gc_win == 0) { 263 /* in which case, p points to an error code which we ignore */ 264 p = ERR_PTR(-EACCES); 265 goto err; 266 } 267 /* copy the opaque wire context */ 268 p = simple_get_netobj(p, end, &ctx->gc_wire_ctx); 269 if (IS_ERR(p)) 270 goto err; 271 /* import the opaque security context */ 272 p = simple_get_bytes(p, end, &seclen, sizeof(seclen)); 273 if (IS_ERR(p)) 274 goto err; 275 q = (const void *)((const char *)p + seclen); 276 if (unlikely(q > end || q < p)) { 277 p = ERR_PTR(-EFAULT); 278 goto err; 279 } 280 ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx); 281 if (ret < 0) { 282 p = ERR_PTR(ret); 283 goto err; 284 } 285 return q; 286 err: 287 dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p)); 288 return p; 289 } 290 291 292 struct gss_upcall_msg { 293 atomic_t count; 294 uid_t uid; 295 struct rpc_pipe_msg msg; 296 struct list_head list; 297 struct gss_auth *auth; 298 struct rpc_wait_queue rpc_waitqueue; 299 wait_queue_head_t waitqueue; 300 struct gss_cl_ctx *ctx; 301 }; 302 303 static void 304 gss_release_msg(struct gss_upcall_msg *gss_msg) 305 { 306 if (!atomic_dec_and_test(&gss_msg->count)) 307 return; 308 BUG_ON(!list_empty(&gss_msg->list)); 309 if (gss_msg->ctx != NULL) 310 gss_put_ctx(gss_msg->ctx); 311 kfree(gss_msg); 312 } 313 314 static struct gss_upcall_msg * 315 __gss_find_upcall(struct gss_auth *gss_auth, uid_t uid) 316 { 317 struct gss_upcall_msg *pos; 318 list_for_each_entry(pos, &gss_auth->upcalls, list) { 319 if (pos->uid != uid) 320 continue; 321 atomic_inc(&pos->count); 322 dprintk("RPC: gss_find_upcall found msg %p\n", pos); 323 return pos; 324 } 325 dprintk("RPC: gss_find_upcall found nothing\n"); 326 return NULL; 327 } 328 329 /* Try to add a upcall to the pipefs queue. 330 * If an upcall owned by our uid already exists, then we return a reference 331 * to that upcall instead of adding the new upcall. 332 */ 333 static inline struct gss_upcall_msg * 334 gss_add_msg(struct gss_auth *gss_auth, struct gss_upcall_msg *gss_msg) 335 { 336 struct gss_upcall_msg *old; 337 338 spin_lock(&gss_auth->lock); 339 old = __gss_find_upcall(gss_auth, gss_msg->uid); 340 if (old == NULL) { 341 atomic_inc(&gss_msg->count); 342 list_add(&gss_msg->list, &gss_auth->upcalls); 343 } else 344 gss_msg = old; 345 spin_unlock(&gss_auth->lock); 346 return gss_msg; 347 } 348 349 static void 350 __gss_unhash_msg(struct gss_upcall_msg *gss_msg) 351 { 352 if (list_empty(&gss_msg->list)) 353 return; 354 list_del_init(&gss_msg->list); 355 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 356 wake_up_all(&gss_msg->waitqueue); 357 atomic_dec(&gss_msg->count); 358 } 359 360 static void 361 gss_unhash_msg(struct gss_upcall_msg *gss_msg) 362 { 363 struct gss_auth *gss_auth = gss_msg->auth; 364 365 spin_lock(&gss_auth->lock); 366 __gss_unhash_msg(gss_msg); 367 spin_unlock(&gss_auth->lock); 368 } 369 370 static void 371 gss_upcall_callback(struct rpc_task *task) 372 { 373 struct gss_cred *gss_cred = container_of(task->tk_msg.rpc_cred, 374 struct gss_cred, gc_base); 375 struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall; 376 377 BUG_ON(gss_msg == NULL); 378 if (gss_msg->ctx) 379 gss_cred_set_ctx(task->tk_msg.rpc_cred, gss_get_ctx(gss_msg->ctx)); 380 else 381 task->tk_status = gss_msg->msg.errno; 382 spin_lock(&gss_msg->auth->lock); 383 gss_cred->gc_upcall = NULL; 384 rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno); 385 spin_unlock(&gss_msg->auth->lock); 386 gss_release_msg(gss_msg); 387 } 388 389 static inline struct gss_upcall_msg * 390 gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid) 391 { 392 struct gss_upcall_msg *gss_msg; 393 394 gss_msg = kmalloc(sizeof(*gss_msg), GFP_KERNEL); 395 if (gss_msg != NULL) { 396 memset(gss_msg, 0, sizeof(*gss_msg)); 397 INIT_LIST_HEAD(&gss_msg->list); 398 rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq"); 399 init_waitqueue_head(&gss_msg->waitqueue); 400 atomic_set(&gss_msg->count, 1); 401 gss_msg->msg.data = &gss_msg->uid; 402 gss_msg->msg.len = sizeof(gss_msg->uid); 403 gss_msg->uid = uid; 404 gss_msg->auth = gss_auth; 405 } 406 return gss_msg; 407 } 408 409 static struct gss_upcall_msg * 410 gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred) 411 { 412 struct gss_upcall_msg *gss_new, *gss_msg; 413 414 gss_new = gss_alloc_msg(gss_auth, cred->cr_uid); 415 if (gss_new == NULL) 416 return ERR_PTR(-ENOMEM); 417 gss_msg = gss_add_msg(gss_auth, gss_new); 418 if (gss_msg == gss_new) { 419 int res = rpc_queue_upcall(gss_auth->dentry->d_inode, &gss_new->msg); 420 if (res) { 421 gss_unhash_msg(gss_new); 422 gss_msg = ERR_PTR(res); 423 } 424 } else 425 gss_release_msg(gss_new); 426 return gss_msg; 427 } 428 429 static inline int 430 gss_refresh_upcall(struct rpc_task *task) 431 { 432 struct rpc_cred *cred = task->tk_msg.rpc_cred; 433 struct gss_auth *gss_auth = container_of(task->tk_client->cl_auth, 434 struct gss_auth, rpc_auth); 435 struct gss_cred *gss_cred = container_of(cred, 436 struct gss_cred, gc_base); 437 struct gss_upcall_msg *gss_msg; 438 int err = 0; 439 440 dprintk("RPC: %4u gss_refresh_upcall for uid %u\n", task->tk_pid, cred->cr_uid); 441 gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred); 442 if (IS_ERR(gss_msg)) { 443 err = PTR_ERR(gss_msg); 444 goto out; 445 } 446 spin_lock(&gss_auth->lock); 447 if (gss_cred->gc_upcall != NULL) 448 rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL, NULL); 449 else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) { 450 task->tk_timeout = 0; 451 gss_cred->gc_upcall = gss_msg; 452 /* gss_upcall_callback will release the reference to gss_upcall_msg */ 453 atomic_inc(&gss_msg->count); 454 rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback, NULL); 455 } else 456 err = gss_msg->msg.errno; 457 spin_unlock(&gss_auth->lock); 458 gss_release_msg(gss_msg); 459 out: 460 dprintk("RPC: %4u gss_refresh_upcall for uid %u result %d\n", task->tk_pid, 461 cred->cr_uid, err); 462 return err; 463 } 464 465 static inline int 466 gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred) 467 { 468 struct rpc_cred *cred = &gss_cred->gc_base; 469 struct gss_upcall_msg *gss_msg; 470 DEFINE_WAIT(wait); 471 int err = 0; 472 473 dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid); 474 gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred); 475 if (IS_ERR(gss_msg)) { 476 err = PTR_ERR(gss_msg); 477 goto out; 478 } 479 for (;;) { 480 prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE); 481 spin_lock(&gss_auth->lock); 482 if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) { 483 spin_unlock(&gss_auth->lock); 484 break; 485 } 486 spin_unlock(&gss_auth->lock); 487 if (signalled()) { 488 err = -ERESTARTSYS; 489 goto out_intr; 490 } 491 schedule(); 492 } 493 if (gss_msg->ctx) 494 gss_cred_set_ctx(cred, gss_get_ctx(gss_msg->ctx)); 495 else 496 err = gss_msg->msg.errno; 497 out_intr: 498 finish_wait(&gss_msg->waitqueue, &wait); 499 gss_release_msg(gss_msg); 500 out: 501 dprintk("RPC: gss_create_upcall for uid %u result %d\n", cred->cr_uid, err); 502 return err; 503 } 504 505 static ssize_t 506 gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg, 507 char __user *dst, size_t buflen) 508 { 509 char *data = (char *)msg->data + msg->copied; 510 ssize_t mlen = msg->len; 511 ssize_t left; 512 513 if (mlen > buflen) 514 mlen = buflen; 515 left = copy_to_user(dst, data, mlen); 516 if (left < 0) { 517 msg->errno = left; 518 return left; 519 } 520 mlen -= left; 521 msg->copied += mlen; 522 msg->errno = 0; 523 return mlen; 524 } 525 526 #define MSG_BUF_MAXSIZE 1024 527 528 static ssize_t 529 gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) 530 { 531 const void *p, *end; 532 void *buf; 533 struct rpc_clnt *clnt; 534 struct gss_auth *gss_auth; 535 struct rpc_cred *cred; 536 struct gss_upcall_msg *gss_msg; 537 struct gss_cl_ctx *ctx; 538 uid_t uid; 539 int err = -EFBIG; 540 541 if (mlen > MSG_BUF_MAXSIZE) 542 goto out; 543 err = -ENOMEM; 544 buf = kmalloc(mlen, GFP_KERNEL); 545 if (!buf) 546 goto out; 547 548 clnt = RPC_I(filp->f_dentry->d_inode)->private; 549 err = -EFAULT; 550 if (copy_from_user(buf, src, mlen)) 551 goto err; 552 553 end = (const void *)((char *)buf + mlen); 554 p = simple_get_bytes(buf, end, &uid, sizeof(uid)); 555 if (IS_ERR(p)) { 556 err = PTR_ERR(p); 557 goto err; 558 } 559 560 err = -ENOMEM; 561 ctx = gss_alloc_context(); 562 if (ctx == NULL) 563 goto err; 564 err = 0; 565 gss_auth = container_of(clnt->cl_auth, struct gss_auth, rpc_auth); 566 p = gss_fill_context(p, end, ctx, gss_auth->mech); 567 if (IS_ERR(p)) { 568 err = PTR_ERR(p); 569 if (err != -EACCES) 570 goto err_put_ctx; 571 } 572 spin_lock(&gss_auth->lock); 573 gss_msg = __gss_find_upcall(gss_auth, uid); 574 if (gss_msg) { 575 if (err == 0 && gss_msg->ctx == NULL) 576 gss_msg->ctx = gss_get_ctx(ctx); 577 gss_msg->msg.errno = err; 578 __gss_unhash_msg(gss_msg); 579 spin_unlock(&gss_auth->lock); 580 gss_release_msg(gss_msg); 581 } else { 582 struct auth_cred acred = { .uid = uid }; 583 spin_unlock(&gss_auth->lock); 584 cred = rpcauth_lookup_credcache(clnt->cl_auth, &acred, 0); 585 if (IS_ERR(cred)) { 586 err = PTR_ERR(cred); 587 goto err_put_ctx; 588 } 589 gss_cred_set_ctx(cred, gss_get_ctx(ctx)); 590 } 591 gss_put_ctx(ctx); 592 kfree(buf); 593 dprintk("RPC: gss_pipe_downcall returning length %Zu\n", mlen); 594 return mlen; 595 err_put_ctx: 596 gss_put_ctx(ctx); 597 err: 598 kfree(buf); 599 out: 600 dprintk("RPC: gss_pipe_downcall returning %d\n", err); 601 return err; 602 } 603 604 static void 605 gss_pipe_release(struct inode *inode) 606 { 607 struct rpc_inode *rpci = RPC_I(inode); 608 struct rpc_clnt *clnt; 609 struct rpc_auth *auth; 610 struct gss_auth *gss_auth; 611 612 clnt = rpci->private; 613 auth = clnt->cl_auth; 614 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 615 spin_lock(&gss_auth->lock); 616 while (!list_empty(&gss_auth->upcalls)) { 617 struct gss_upcall_msg *gss_msg; 618 619 gss_msg = list_entry(gss_auth->upcalls.next, 620 struct gss_upcall_msg, list); 621 gss_msg->msg.errno = -EPIPE; 622 atomic_inc(&gss_msg->count); 623 __gss_unhash_msg(gss_msg); 624 spin_unlock(&gss_auth->lock); 625 gss_release_msg(gss_msg); 626 spin_lock(&gss_auth->lock); 627 } 628 spin_unlock(&gss_auth->lock); 629 } 630 631 static void 632 gss_pipe_destroy_msg(struct rpc_pipe_msg *msg) 633 { 634 struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg); 635 static unsigned long ratelimit; 636 637 if (msg->errno < 0) { 638 dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n", 639 gss_msg); 640 atomic_inc(&gss_msg->count); 641 gss_unhash_msg(gss_msg); 642 if (msg->errno == -ETIMEDOUT || msg->errno == -EPIPE) { 643 unsigned long now = jiffies; 644 if (time_after(now, ratelimit)) { 645 printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n" 646 "Please check user daemon is running!\n"); 647 ratelimit = now + 15*HZ; 648 } 649 } 650 gss_release_msg(gss_msg); 651 } 652 } 653 654 /* 655 * NOTE: we have the opportunity to use different 656 * parameters based on the input flavor (which must be a pseudoflavor) 657 */ 658 static struct rpc_auth * 659 gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 660 { 661 struct gss_auth *gss_auth; 662 struct rpc_auth * auth; 663 int err = -ENOMEM; /* XXX? */ 664 665 dprintk("RPC: creating GSS authenticator for client %p\n",clnt); 666 667 if (!try_module_get(THIS_MODULE)) 668 return ERR_PTR(err); 669 if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL))) 670 goto out_dec; 671 gss_auth->client = clnt; 672 err = -EINVAL; 673 gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor); 674 if (!gss_auth->mech) { 675 printk(KERN_WARNING "%s: Pseudoflavor %d not found!", 676 __FUNCTION__, flavor); 677 goto err_free; 678 } 679 gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor); 680 if (gss_auth->service == 0) 681 goto err_put_mech; 682 INIT_LIST_HEAD(&gss_auth->upcalls); 683 spin_lock_init(&gss_auth->lock); 684 auth = &gss_auth->rpc_auth; 685 auth->au_cslack = GSS_CRED_SLACK >> 2; 686 auth->au_rslack = GSS_VERF_SLACK >> 2; 687 auth->au_ops = &authgss_ops; 688 auth->au_flavor = flavor; 689 atomic_set(&auth->au_count, 1); 690 691 err = rpcauth_init_credcache(auth, GSS_CRED_EXPIRE); 692 if (err) 693 goto err_put_mech; 694 695 snprintf(gss_auth->path, sizeof(gss_auth->path), "%s/%s", 696 clnt->cl_pathname, 697 gss_auth->mech->gm_name); 698 gss_auth->dentry = rpc_mkpipe(gss_auth->path, clnt, &gss_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN); 699 if (IS_ERR(gss_auth->dentry)) { 700 err = PTR_ERR(gss_auth->dentry); 701 goto err_put_mech; 702 } 703 704 return auth; 705 err_put_mech: 706 gss_mech_put(gss_auth->mech); 707 err_free: 708 kfree(gss_auth); 709 out_dec: 710 module_put(THIS_MODULE); 711 return ERR_PTR(err); 712 } 713 714 static void 715 gss_destroy(struct rpc_auth *auth) 716 { 717 struct gss_auth *gss_auth; 718 719 dprintk("RPC: destroying GSS authenticator %p flavor %d\n", 720 auth, auth->au_flavor); 721 722 gss_auth = container_of(auth, struct gss_auth, rpc_auth); 723 rpc_unlink(gss_auth->path); 724 gss_mech_put(gss_auth->mech); 725 726 rpcauth_free_credcache(auth); 727 kfree(gss_auth); 728 module_put(THIS_MODULE); 729 } 730 731 /* gss_destroy_cred (and gss_destroy_ctx) are used to clean up after failure 732 * to create a new cred or context, so they check that things have been 733 * allocated before freeing them. */ 734 static void 735 gss_destroy_ctx(struct gss_cl_ctx *ctx) 736 { 737 dprintk("RPC: gss_destroy_ctx\n"); 738 739 if (ctx->gc_gss_ctx) 740 gss_delete_sec_context(&ctx->gc_gss_ctx); 741 742 kfree(ctx->gc_wire_ctx.data); 743 kfree(ctx); 744 } 745 746 static void 747 gss_destroy_cred(struct rpc_cred *rc) 748 { 749 struct gss_cred *cred = container_of(rc, struct gss_cred, gc_base); 750 751 dprintk("RPC: gss_destroy_cred \n"); 752 753 if (cred->gc_ctx) 754 gss_put_ctx(cred->gc_ctx); 755 kfree(cred); 756 } 757 758 /* 759 * Lookup RPCSEC_GSS cred for the current process 760 */ 761 static struct rpc_cred * 762 gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int taskflags) 763 { 764 return rpcauth_lookup_credcache(auth, acred, taskflags); 765 } 766 767 static struct rpc_cred * 768 gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int taskflags) 769 { 770 struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth); 771 struct gss_cred *cred = NULL; 772 int err = -ENOMEM; 773 774 dprintk("RPC: gss_create_cred for uid %d, flavor %d\n", 775 acred->uid, auth->au_flavor); 776 777 if (!(cred = kmalloc(sizeof(*cred), GFP_KERNEL))) 778 goto out_err; 779 780 memset(cred, 0, sizeof(*cred)); 781 atomic_set(&cred->gc_count, 1); 782 cred->gc_uid = acred->uid; 783 /* 784 * Note: in order to force a call to call_refresh(), we deliberately 785 * fail to flag the credential as RPCAUTH_CRED_UPTODATE. 786 */ 787 cred->gc_flags = 0; 788 cred->gc_base.cr_ops = &gss_credops; 789 cred->gc_service = gss_auth->service; 790 err = gss_create_upcall(gss_auth, cred); 791 if (err < 0) 792 goto out_err; 793 794 return &cred->gc_base; 795 796 out_err: 797 dprintk("RPC: gss_create_cred failed with error %d\n", err); 798 if (cred) gss_destroy_cred(&cred->gc_base); 799 return ERR_PTR(err); 800 } 801 802 static int 803 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int taskflags) 804 { 805 struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base); 806 807 /* Don't match with creds that have expired. */ 808 if (gss_cred->gc_ctx && time_after(jiffies, gss_cred->gc_ctx->gc_expiry)) 809 return 0; 810 return (rc->cr_uid == acred->uid); 811 } 812 813 /* 814 * Marshal credentials. 815 * Maybe we should keep a cached credential for performance reasons. 816 */ 817 static u32 * 818 gss_marshal(struct rpc_task *task, u32 *p) 819 { 820 struct rpc_cred *cred = task->tk_msg.rpc_cred; 821 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 822 gc_base); 823 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 824 u32 *cred_len; 825 struct rpc_rqst *req = task->tk_rqstp; 826 u32 maj_stat = 0; 827 struct xdr_netobj mic; 828 struct kvec iov; 829 struct xdr_buf verf_buf; 830 831 dprintk("RPC: %4u gss_marshal\n", task->tk_pid); 832 833 *p++ = htonl(RPC_AUTH_GSS); 834 cred_len = p++; 835 836 spin_lock(&ctx->gc_seq_lock); 837 req->rq_seqno = ctx->gc_seq++; 838 spin_unlock(&ctx->gc_seq_lock); 839 840 *p++ = htonl((u32) RPC_GSS_VERSION); 841 *p++ = htonl((u32) ctx->gc_proc); 842 *p++ = htonl((u32) req->rq_seqno); 843 *p++ = htonl((u32) gss_cred->gc_service); 844 p = xdr_encode_netobj(p, &ctx->gc_wire_ctx); 845 *cred_len = htonl((p - (cred_len + 1)) << 2); 846 847 /* We compute the checksum for the verifier over the xdr-encoded bytes 848 * starting with the xid and ending at the end of the credential: */ 849 iov.iov_base = req->rq_snd_buf.head[0].iov_base; 850 if (task->tk_client->cl_xprt->stream) 851 /* See clnt.c:call_header() */ 852 iov.iov_base += 4; 853 iov.iov_len = (u8 *)p - (u8 *)iov.iov_base; 854 xdr_buf_from_iov(&iov, &verf_buf); 855 856 /* set verifier flavor*/ 857 *p++ = htonl(RPC_AUTH_GSS); 858 859 mic.data = (u8 *)(p + 1); 860 maj_stat = gss_get_mic(ctx->gc_gss_ctx, 861 GSS_C_QOP_DEFAULT, 862 &verf_buf, &mic); 863 if (maj_stat == GSS_S_CONTEXT_EXPIRED) { 864 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 865 } else if (maj_stat != 0) { 866 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat); 867 goto out_put_ctx; 868 } 869 p = xdr_encode_opaque(p, NULL, mic.len); 870 gss_put_ctx(ctx); 871 return p; 872 out_put_ctx: 873 gss_put_ctx(ctx); 874 return NULL; 875 } 876 877 /* 878 * Refresh credentials. XXX - finish 879 */ 880 static int 881 gss_refresh(struct rpc_task *task) 882 { 883 884 if (!gss_cred_is_uptodate_ctx(task->tk_msg.rpc_cred)) 885 return gss_refresh_upcall(task); 886 return 0; 887 } 888 889 static u32 * 890 gss_validate(struct rpc_task *task, u32 *p) 891 { 892 struct rpc_cred *cred = task->tk_msg.rpc_cred; 893 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 894 gc_base); 895 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 896 u32 seq, qop_state; 897 struct kvec iov; 898 struct xdr_buf verf_buf; 899 struct xdr_netobj mic; 900 u32 flav,len; 901 u32 maj_stat; 902 903 dprintk("RPC: %4u gss_validate\n", task->tk_pid); 904 905 flav = ntohl(*p++); 906 if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE) 907 goto out_bad; 908 if (flav != RPC_AUTH_GSS) 909 goto out_bad; 910 seq = htonl(task->tk_rqstp->rq_seqno); 911 iov.iov_base = &seq; 912 iov.iov_len = sizeof(seq); 913 xdr_buf_from_iov(&iov, &verf_buf); 914 mic.data = (u8 *)p; 915 mic.len = len; 916 917 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic, &qop_state); 918 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 919 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 920 if (maj_stat) 921 goto out_bad; 922 switch (gss_cred->gc_service) { 923 case RPC_GSS_SVC_NONE: 924 /* verifier data, flavor, length: */ 925 task->tk_auth->au_rslack = XDR_QUADLEN(len) + 2; 926 break; 927 case RPC_GSS_SVC_INTEGRITY: 928 /* verifier data, flavor, length, length, sequence number: */ 929 task->tk_auth->au_rslack = XDR_QUADLEN(len) + 4; 930 break; 931 case RPC_GSS_SVC_PRIVACY: 932 goto out_bad; 933 } 934 gss_put_ctx(ctx); 935 dprintk("RPC: %4u GSS gss_validate: gss_verify_mic succeeded.\n", 936 task->tk_pid); 937 return p + XDR_QUADLEN(len); 938 out_bad: 939 gss_put_ctx(ctx); 940 dprintk("RPC: %4u gss_validate failed.\n", task->tk_pid); 941 return NULL; 942 } 943 944 static inline int 945 gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 946 kxdrproc_t encode, struct rpc_rqst *rqstp, u32 *p, void *obj) 947 { 948 struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; 949 struct xdr_buf integ_buf; 950 u32 *integ_len = NULL; 951 struct xdr_netobj mic; 952 u32 offset, *q; 953 struct kvec *iov; 954 u32 maj_stat = 0; 955 int status = -EIO; 956 957 integ_len = p++; 958 offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base; 959 *p++ = htonl(rqstp->rq_seqno); 960 961 status = encode(rqstp, p, obj); 962 if (status) 963 return status; 964 965 if (xdr_buf_subsegment(snd_buf, &integ_buf, 966 offset, snd_buf->len - offset)) 967 return status; 968 *integ_len = htonl(integ_buf.len); 969 970 /* guess whether we're in the head or the tail: */ 971 if (snd_buf->page_len || snd_buf->tail[0].iov_len) 972 iov = snd_buf->tail; 973 else 974 iov = snd_buf->head; 975 p = iov->iov_base + iov->iov_len; 976 mic.data = (u8 *)(p + 1); 977 978 maj_stat = gss_get_mic(ctx->gc_gss_ctx, 979 GSS_C_QOP_DEFAULT, &integ_buf, &mic); 980 status = -EIO; /* XXX? */ 981 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 982 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 983 else if (maj_stat) 984 return status; 985 q = xdr_encode_opaque(p, NULL, mic.len); 986 987 offset = (u8 *)q - (u8 *)p; 988 iov->iov_len += offset; 989 snd_buf->len += offset; 990 return 0; 991 } 992 993 static int 994 gss_wrap_req(struct rpc_task *task, 995 kxdrproc_t encode, void *rqstp, u32 *p, void *obj) 996 { 997 struct rpc_cred *cred = task->tk_msg.rpc_cred; 998 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 999 gc_base); 1000 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1001 int status = -EIO; 1002 1003 dprintk("RPC: %4u gss_wrap_req\n", task->tk_pid); 1004 if (ctx->gc_proc != RPC_GSS_PROC_DATA) { 1005 /* The spec seems a little ambiguous here, but I think that not 1006 * wrapping context destruction requests makes the most sense. 1007 */ 1008 status = encode(rqstp, p, obj); 1009 goto out; 1010 } 1011 switch (gss_cred->gc_service) { 1012 case RPC_GSS_SVC_NONE: 1013 status = encode(rqstp, p, obj); 1014 break; 1015 case RPC_GSS_SVC_INTEGRITY: 1016 status = gss_wrap_req_integ(cred, ctx, encode, 1017 rqstp, p, obj); 1018 break; 1019 case RPC_GSS_SVC_PRIVACY: 1020 break; 1021 } 1022 out: 1023 gss_put_ctx(ctx); 1024 dprintk("RPC: %4u gss_wrap_req returning %d\n", task->tk_pid, status); 1025 return status; 1026 } 1027 1028 static inline int 1029 gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx, 1030 struct rpc_rqst *rqstp, u32 **p) 1031 { 1032 struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; 1033 struct xdr_buf integ_buf; 1034 struct xdr_netobj mic; 1035 u32 data_offset, mic_offset; 1036 u32 integ_len; 1037 u32 maj_stat; 1038 int status = -EIO; 1039 1040 integ_len = ntohl(*(*p)++); 1041 if (integ_len & 3) 1042 return status; 1043 data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base; 1044 mic_offset = integ_len + data_offset; 1045 if (mic_offset > rcv_buf->len) 1046 return status; 1047 if (ntohl(*(*p)++) != rqstp->rq_seqno) 1048 return status; 1049 1050 if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, 1051 mic_offset - data_offset)) 1052 return status; 1053 1054 if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset)) 1055 return status; 1056 1057 maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, 1058 &mic, NULL); 1059 if (maj_stat == GSS_S_CONTEXT_EXPIRED) 1060 cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE; 1061 if (maj_stat != GSS_S_COMPLETE) 1062 return status; 1063 return 0; 1064 } 1065 1066 static int 1067 gss_unwrap_resp(struct rpc_task *task, 1068 kxdrproc_t decode, void *rqstp, u32 *p, void *obj) 1069 { 1070 struct rpc_cred *cred = task->tk_msg.rpc_cred; 1071 struct gss_cred *gss_cred = container_of(cred, struct gss_cred, 1072 gc_base); 1073 struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred); 1074 int status = -EIO; 1075 1076 if (ctx->gc_proc != RPC_GSS_PROC_DATA) 1077 goto out_decode; 1078 switch (gss_cred->gc_service) { 1079 case RPC_GSS_SVC_NONE: 1080 break; 1081 case RPC_GSS_SVC_INTEGRITY: 1082 status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p); 1083 if (status) 1084 goto out; 1085 break; 1086 case RPC_GSS_SVC_PRIVACY: 1087 break; 1088 } 1089 out_decode: 1090 status = decode(rqstp, p, obj); 1091 out: 1092 gss_put_ctx(ctx); 1093 dprintk("RPC: %4u gss_unwrap_resp returning %d\n", task->tk_pid, 1094 status); 1095 return status; 1096 } 1097 1098 static struct rpc_authops authgss_ops = { 1099 .owner = THIS_MODULE, 1100 .au_flavor = RPC_AUTH_GSS, 1101 #ifdef RPC_DEBUG 1102 .au_name = "RPCSEC_GSS", 1103 #endif 1104 .create = gss_create, 1105 .destroy = gss_destroy, 1106 .lookup_cred = gss_lookup_cred, 1107 .crcreate = gss_create_cred 1108 }; 1109 1110 static struct rpc_credops gss_credops = { 1111 .cr_name = "AUTH_GSS", 1112 .crdestroy = gss_destroy_cred, 1113 .crmatch = gss_match, 1114 .crmarshal = gss_marshal, 1115 .crrefresh = gss_refresh, 1116 .crvalidate = gss_validate, 1117 .crwrap_req = gss_wrap_req, 1118 .crunwrap_resp = gss_unwrap_resp, 1119 }; 1120 1121 static struct rpc_pipe_ops gss_upcall_ops = { 1122 .upcall = gss_pipe_upcall, 1123 .downcall = gss_pipe_downcall, 1124 .destroy_msg = gss_pipe_destroy_msg, 1125 .release_pipe = gss_pipe_release, 1126 }; 1127 1128 /* 1129 * Initialize RPCSEC_GSS module 1130 */ 1131 static int __init init_rpcsec_gss(void) 1132 { 1133 int err = 0; 1134 1135 err = rpcauth_register(&authgss_ops); 1136 if (err) 1137 goto out; 1138 err = gss_svc_init(); 1139 if (err) 1140 goto out_unregister; 1141 return 0; 1142 out_unregister: 1143 rpcauth_unregister(&authgss_ops); 1144 out: 1145 return err; 1146 } 1147 1148 static void __exit exit_rpcsec_gss(void) 1149 { 1150 gss_svc_shutdown(); 1151 rpcauth_unregister(&authgss_ops); 1152 } 1153 1154 MODULE_LICENSE("GPL"); 1155 module_init(init_rpcsec_gss) 1156 module_exit(exit_rpcsec_gss) 1157