1 /* $NetBSD: nfs_export.c,v 1.47 2009/05/23 18:19:19 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 1997, 1998, 2004, 2005, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * This code is derived from software contributed to The NetBSD Foundation 11 * by Charles M. Hannum. 12 * This code is derived from software contributed to The NetBSD Foundation 13 * by Julio M. Merino Vidal. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 26 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 27 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 28 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 /* 38 * Copyright (c) 1989, 1993 39 * The Regents of the University of California. All rights reserved. 40 * (c) UNIX System Laboratories, Inc. 41 * All or some portions of this file are derived from material licensed 42 * to the University of California by American Telephone and Telegraph 43 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 44 * the permission of UNIX System Laboratories, Inc. 45 * 46 * Redistribution and use in source and binary forms, with or without 47 * modification, are permitted provided that the following conditions 48 * are met: 49 * 1. Redistributions of source code must retain the above copyright 50 * notice, this list of conditions and the following disclaimer. 51 * 2. Redistributions in binary form must reproduce the above copyright 52 * notice, this list of conditions and the following disclaimer in the 53 * documentation and/or other materials provided with the distribution. 54 * 3. Neither the name of the University nor the names of its contributors 55 * may be used to endorse or promote products derived from this software 56 * without specific prior written permission. 57 * 58 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 59 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 60 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 61 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 62 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 63 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 64 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 65 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 66 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 67 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 68 * SUCH DAMAGE. 69 * 70 * @(#)vfs_subr.c 8.13 (Berkeley) 4/18/94 71 */ 72 73 /* 74 * VFS exports list management. 75 * 76 * Lock order: vfs_busy -> mnt_updating -> netexport_lock. 77 */ 78 79 #include <sys/cdefs.h> 80 __KERNEL_RCSID(0, "$NetBSD: nfs_export.c,v 1.47 2009/05/23 18:19:19 ad Exp $"); 81 82 #include <sys/param.h> 83 #include <sys/systm.h> 84 #include <sys/kernel.h> 85 #include <sys/queue.h> 86 #include <sys/proc.h> 87 #include <sys/mount.h> 88 #include <sys/vnode.h> 89 #include <sys/namei.h> 90 #include <sys/errno.h> 91 #include <sys/malloc.h> 92 #include <sys/domain.h> 93 #include <sys/mbuf.h> 94 #include <sys/dirent.h> 95 #include <sys/socket.h> /* XXX for AF_MAX */ 96 #include <sys/kauth.h> 97 98 #include <net/radix.h> 99 100 #include <netinet/in.h> 101 102 #include <nfs/rpcv2.h> 103 #include <nfs/nfsproto.h> 104 #include <nfs/nfs.h> 105 #include <nfs/nfs_var.h> 106 107 /* 108 * Network address lookup element. 109 */ 110 struct netcred { 111 struct radix_node netc_rnodes[2]; 112 int netc_refcnt; 113 int netc_exflags; 114 kauth_cred_t netc_anon; 115 }; 116 117 /* 118 * Network export information. 119 */ 120 struct netexport { 121 CIRCLEQ_ENTRY(netexport) ne_list; 122 struct mount *ne_mount; 123 struct netcred ne_defexported; /* Default export */ 124 struct radix_node_head *ne_rtable[AF_MAX+1]; /* Individual exports */ 125 }; 126 CIRCLEQ_HEAD(, netexport) netexport_list = 127 CIRCLEQ_HEAD_INITIALIZER(netexport_list); 128 129 /* Publicly exported file system. */ 130 struct nfs_public nfs_pub; 131 132 /* 133 * Local prototypes. 134 */ 135 static int init_exports(struct mount *, struct netexport **); 136 static int hang_addrlist(struct mount *, struct netexport *, 137 const struct export_args *); 138 static int sacheck(struct sockaddr *); 139 static int free_netcred(struct radix_node *, void *); 140 static int export(struct netexport *, const struct export_args *); 141 static int setpublicfs(struct mount *, struct netexport *, 142 const struct export_args *); 143 static struct netcred *netcred_lookup(struct netexport *, struct mbuf *); 144 static struct netexport *netexport_lookup(const struct mount *); 145 static struct netexport *netexport_lookup_byfsid(const fsid_t *); 146 static void netexport_clear(struct netexport *); 147 static void netexport_insert(struct netexport *); 148 static void netexport_remove(struct netexport *); 149 static void netexport_wrlock(void); 150 static void netexport_wrunlock(void); 151 static int nfs_export_update_30(struct mount *mp, const char *path, void *); 152 153 static krwlock_t netexport_lock; 154 155 /* 156 * PUBLIC INTERFACE 157 */ 158 159 /* 160 * Declare and initialize the file system export hooks. 161 */ 162 static void netexport_unmount(struct mount *); 163 164 struct vfs_hooks nfs_export_hooks = { 165 { NULL, NULL }, 166 .vh_unmount = netexport_unmount, 167 .vh_reexport = nfs_export_update_30, 168 }; 169 170 /* 171 * VFS unmount hook for NFS exports. 172 * 173 * Releases NFS exports list resources if the given mount point has some. 174 * As allocation happens lazily, it may be that it doesn't has this 175 * information, although it theorically should. 176 */ 177 static void 178 netexport_unmount(struct mount *mp) 179 { 180 struct netexport *ne; 181 182 KASSERT(mp != NULL); 183 184 netexport_wrlock(); 185 ne = netexport_lookup(mp); 186 if (ne == NULL) { 187 netexport_wrunlock(); 188 return; 189 } 190 netexport_clear(ne); 191 netexport_remove(ne); 192 netexport_wrunlock(); 193 kmem_free(ne, sizeof(*ne)); 194 } 195 196 void 197 netexport_init(void) 198 { 199 200 rw_init(&netexport_lock); 201 } 202 203 void 204 netexport_fini(void) 205 { 206 struct netexport *ne; 207 struct mount *mp; 208 int error; 209 210 while (!CIRCLEQ_EMPTY(&netexport_list)) { 211 netexport_wrlock(); 212 ne = CIRCLEQ_FIRST(&netexport_list); 213 mp = ne->ne_mount; 214 error = vfs_busy(mp, NULL); 215 netexport_wrunlock(); 216 if (error != 0) { 217 kpause("nfsfini", false, hz, NULL); 218 continue; 219 } 220 mutex_enter(&mp->mnt_updating); /* mnt_flag */ 221 netexport_unmount(mp); 222 mutex_exit(&mp->mnt_updating); /* mnt_flag */ 223 vfs_unbusy(mp, false, NULL); 224 } 225 rw_destroy(&netexport_lock); 226 } 227 228 229 /* 230 * Atomically set the NFS exports list of the given file system, replacing 231 * it with a new list of entries. 232 * 233 * Returns zero on success or an appropriate error code otherwise. 234 * 235 * Helper function for the nfssvc(2) system call (NFSSVC_SETEXPORTSLIST 236 * command). 237 */ 238 int 239 mountd_set_exports_list(const struct mountd_exports_list *mel, struct lwp *l) 240 { 241 int error; 242 #ifdef notyet 243 /* XXX: See below to see the reason why this is disabled. */ 244 size_t i; 245 #endif 246 struct mount *mp; 247 struct netexport *ne; 248 struct nameidata nd; 249 struct vnode *vp; 250 size_t fid_size; 251 252 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_NFS, 253 KAUTH_REQ_NETWORK_NFS_EXPORT, NULL, NULL, NULL) != 0) 254 return EPERM; 255 256 /* Lookup the file system path. */ 257 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE, mel->mel_path); 258 error = namei(&nd); 259 if (error != 0) 260 return error; 261 vp = nd.ni_vp; 262 mp = vp->v_mount; 263 264 /* 265 * Make sure the file system can do vptofh. If the file system 266 * knows the handle's size, just trust it's able to do the 267 * actual translation also (otherwise we should check fhtovp 268 * also, and that's getting a wee bit ridiculous). 269 */ 270 fid_size = 0; 271 if ((error = VFS_VPTOFH(vp, NULL, &fid_size)) != E2BIG) { 272 vput(vp); 273 return EOPNOTSUPP; 274 } 275 276 /* Mark the file system busy. */ 277 error = vfs_busy(mp, NULL); 278 vput(vp); 279 if (error != 0) 280 return error; 281 mutex_enter(&mp->mnt_updating); /* mnt_flag */ 282 netexport_wrlock(); 283 ne = netexport_lookup(mp); 284 if (ne == NULL) { 285 error = init_exports(mp, &ne); 286 if (error != 0) { 287 goto out; 288 } 289 } 290 291 KASSERT(ne != NULL); 292 KASSERT(ne->ne_mount == mp); 293 294 /* 295 * XXX: The part marked as 'notyet' works fine from the kernel's 296 * point of view, in the sense that it is able to atomically update 297 * the complete exports list for a file system. However, supporting 298 * this in mountd(8) requires a lot of work; so, for now, keep the 299 * old behavior of updating a single entry per call. 300 * 301 * When mountd(8) is fixed, just remove the second branch of this 302 * preprocessor conditional and enable the first one. 303 */ 304 #ifdef notyet 305 netexport_clear(ne); 306 for (i = 0; error == 0 && i < mel->mel_nexports; i++) 307 error = export(ne, &mel->mel_exports[i]); 308 #else 309 if (mel->mel_nexports == 0) 310 netexport_clear(ne); 311 else if (mel->mel_nexports == 1) 312 error = export(ne, &mel->mel_exports[0]); 313 else { 314 printf("mountd_set_exports_list: Cannot set more than one " 315 "entry at once (unimplemented)\n"); 316 error = EOPNOTSUPP; 317 } 318 #endif 319 320 out: 321 netexport_wrunlock(); 322 mutex_exit(&mp->mnt_updating); /* mnt_flag */ 323 vfs_unbusy(mp, false, NULL); 324 return error; 325 } 326 327 static void 328 netexport_insert(struct netexport *ne) 329 { 330 331 CIRCLEQ_INSERT_HEAD(&netexport_list, ne, ne_list); 332 } 333 334 static void 335 netexport_remove(struct netexport *ne) 336 { 337 338 CIRCLEQ_REMOVE(&netexport_list, ne, ne_list); 339 } 340 341 static struct netexport * 342 netexport_lookup(const struct mount *mp) 343 { 344 struct netexport *ne; 345 346 CIRCLEQ_FOREACH(ne, &netexport_list, ne_list) { 347 if (ne->ne_mount == mp) { 348 goto done; 349 } 350 } 351 ne = NULL; 352 done: 353 return ne; 354 } 355 356 static struct netexport * 357 netexport_lookup_byfsid(const fsid_t *fsid) 358 { 359 struct netexport *ne; 360 361 CIRCLEQ_FOREACH(ne, &netexport_list, ne_list) { 362 const struct mount *mp = ne->ne_mount; 363 364 if (mp->mnt_stat.f_fsidx.__fsid_val[0] == fsid->__fsid_val[0] && 365 mp->mnt_stat.f_fsidx.__fsid_val[1] == fsid->__fsid_val[1]) { 366 goto done; 367 } 368 } 369 ne = NULL; 370 done: 371 372 return ne; 373 } 374 375 /* 376 * Check if the file system specified by the 'mp' mount structure is 377 * exported to a client with 'anon' anonymous credentials. The 'mb' 378 * argument is an mbuf containing the network address of the client. 379 * The return parameters for the export flags for the client are returned 380 * in the address specified by 'wh'. 381 * 382 * This function is used exclusively by the NFS server. It is generally 383 * invoked before VFS_FHTOVP to validate that client has access to the 384 * file system. 385 */ 386 387 int 388 netexport_check(const fsid_t *fsid, struct mbuf *mb, struct mount **mpp, 389 int *wh, kauth_cred_t *anon) 390 { 391 struct netexport *ne; 392 struct netcred *np; 393 394 ne = netexport_lookup_byfsid(fsid); 395 if (ne == NULL) { 396 return EACCES; 397 } 398 np = netcred_lookup(ne, mb); 399 if (np == NULL) { 400 return EACCES; 401 } 402 403 *mpp = ne->ne_mount; 404 *wh = np->netc_exflags; 405 *anon = np->netc_anon; 406 407 return 0; 408 } 409 410 /* 411 * Handles legacy export requests. In this case, the export information 412 * is hardcoded in a specific place of the mount arguments structure (given 413 * in data); the request for an update is given through the fspec field 414 * (also in a known location), which must be a null pointer. 415 * 416 * Returns EJUSTRETURN if the given command was not a export request. 417 * Otherwise, returns 0 on success or an appropriate error code otherwise. 418 */ 419 static int 420 nfs_export_update_30(struct mount *mp, const char *path, void *data) 421 { 422 struct mountd_exports_list mel; 423 struct mnt_export_args30 *args; 424 425 args = data; 426 mel.mel_path = path; 427 428 if (args->fspec != NULL) 429 return EJUSTRETURN; 430 431 if (args->eargs.ex_flags & 0x00020000) { 432 /* Request to delete exports. The mask above holds the 433 * value that used to be in MNT_DELEXPORT. */ 434 mel.mel_nexports = 0; 435 } else { 436 /* The following assumes export_args has not changed since 437 * export_args30 - typedef checks sizes. */ 438 typedef char x[sizeof args->eargs == sizeof *mel.mel_exports ? 1 : -1]; 439 440 mel.mel_nexports = 1; 441 mel.mel_exports = (void *)&args->eargs; 442 } 443 444 return mountd_set_exports_list(&mel, curlwp); 445 } 446 447 /* 448 * INTERNAL FUNCTIONS 449 */ 450 451 /* 452 * Initializes NFS exports for the mountpoint given in 'mp'. 453 * If successful, returns 0 and sets *nep to the address of the new 454 * netexport item; otherwise returns an appropriate error code 455 * and *nep remains unmodified. 456 */ 457 static int 458 init_exports(struct mount *mp, struct netexport **nep) 459 { 460 int error; 461 struct export_args ea; 462 struct netexport *ne; 463 464 KASSERT(mp != NULL); 465 466 /* Ensure that we do not already have this mount point. */ 467 KASSERT(netexport_lookup(mp) == NULL); 468 469 ne = kmem_zalloc(sizeof(*ne), KM_SLEEP); 470 ne->ne_mount = mp; 471 472 /* Set the default export entry. Handled internally by export upon 473 * first call. */ 474 memset(&ea, 0, sizeof(ea)); 475 ea.ex_root = -2; 476 if (mp->mnt_flag & MNT_RDONLY) 477 ea.ex_flags |= MNT_EXRDONLY; 478 error = export(ne, &ea); 479 if (error != 0) { 480 kmem_free(ne, sizeof(*ne)); 481 } else { 482 netexport_insert(ne); 483 *nep = ne; 484 } 485 486 return error; 487 } 488 489 /* 490 * Build hash lists of net addresses and hang them off the mount point. 491 * Called by export() to set up a new entry in the lists of export 492 * addresses. 493 */ 494 static int 495 hang_addrlist(struct mount *mp, struct netexport *nep, 496 const struct export_args *argp) 497 { 498 int error, i; 499 struct netcred *np, *enp; 500 struct radix_node_head *rnh; 501 struct sockaddr *saddr, *smask; 502 struct domain *dom; 503 504 smask = NULL; 505 506 if (argp->ex_addrlen == 0) { 507 if (mp->mnt_flag & MNT_DEFEXPORTED) 508 return EPERM; 509 np = &nep->ne_defexported; 510 KASSERT(np->netc_anon == NULL); 511 np->netc_anon = kauth_cred_alloc(); 512 np->netc_exflags = argp->ex_flags; 513 kauth_uucred_to_cred(np->netc_anon, &argp->ex_anon); 514 mp->mnt_flag |= MNT_DEFEXPORTED; 515 return 0; 516 } 517 518 if (argp->ex_addrlen > MLEN || argp->ex_masklen > MLEN) 519 return EINVAL; 520 521 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 522 np = malloc(i, M_NETADDR, M_WAITOK | M_ZERO); 523 np->netc_anon = kauth_cred_alloc(); 524 saddr = (struct sockaddr *)(np + 1); 525 error = copyin(argp->ex_addr, saddr, argp->ex_addrlen); 526 if (error) 527 goto out; 528 if (saddr->sa_len > argp->ex_addrlen) 529 saddr->sa_len = argp->ex_addrlen; 530 if (sacheck(saddr) == -1) 531 return EINVAL; 532 if (argp->ex_masklen) { 533 smask = (struct sockaddr *)((char *)saddr + argp->ex_addrlen); 534 error = copyin(argp->ex_mask, smask, argp->ex_masklen); 535 if (error) 536 goto out; 537 if (smask->sa_len > argp->ex_masklen) 538 smask->sa_len = argp->ex_masklen; 539 if (smask->sa_family != saddr->sa_family) 540 return EINVAL; 541 if (sacheck(smask) == -1) 542 return EINVAL; 543 } 544 i = saddr->sa_family; 545 if ((rnh = nep->ne_rtable[i]) == 0) { 546 /* 547 * Seems silly to initialize every AF when most are not 548 * used, do so on demand here 549 */ 550 DOMAIN_FOREACH(dom) { 551 if (dom->dom_family == i && dom->dom_rtattach) { 552 dom->dom_rtattach((void **)&nep->ne_rtable[i], 553 dom->dom_rtoffset); 554 break; 555 } 556 } 557 if ((rnh = nep->ne_rtable[i]) == 0) { 558 error = ENOBUFS; 559 goto out; 560 } 561 } 562 563 enp = (struct netcred *)(*rnh->rnh_addaddr)(saddr, smask, rnh, 564 np->netc_rnodes); 565 if (enp != np) { 566 if (enp == NULL) { 567 enp = (struct netcred *)(*rnh->rnh_lookup)(saddr, 568 smask, rnh); 569 if (enp == NULL) { 570 error = EPERM; 571 goto out; 572 } 573 } else 574 enp->netc_refcnt++; 575 576 goto check; 577 } else 578 enp->netc_refcnt = 1; 579 580 np->netc_exflags = argp->ex_flags; 581 kauth_uucred_to_cred(np->netc_anon, &argp->ex_anon); 582 return 0; 583 check: 584 if (enp->netc_exflags != argp->ex_flags || 585 kauth_cred_uucmp(enp->netc_anon, &argp->ex_anon) != 0) 586 error = EPERM; 587 else 588 error = 0; 589 out: 590 KASSERT(np->netc_anon != NULL); 591 kauth_cred_free(np->netc_anon); 592 free(np, M_NETADDR); 593 return error; 594 } 595 596 /* 597 * Ensure that the address stored in 'sa' is valid. 598 * Returns zero on success, otherwise -1. 599 */ 600 static int 601 sacheck(struct sockaddr *sa) 602 { 603 604 switch (sa->sa_family) { 605 case AF_INET: { 606 struct sockaddr_in *sin = (struct sockaddr_in *)sa; 607 char *p = (char *)sin->sin_zero; 608 size_t i; 609 610 if (sin->sin_len != sizeof(*sin)) 611 return -1; 612 if (sin->sin_port != 0) 613 return -1; 614 for (i = 0; i < sizeof(sin->sin_zero); i++) 615 if (*p++ != '\0') 616 return -1; 617 return 0; 618 } 619 case AF_INET6: { 620 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa; 621 622 if (sin6->sin6_len != sizeof(*sin6)) 623 return -1; 624 if (sin6->sin6_port != 0) 625 return -1; 626 return 0; 627 } 628 default: 629 return -1; 630 } 631 } 632 633 /* 634 * Free the netcred object pointed to by the 'rn' radix node. 635 * 'w' holds a pointer to the radix tree head. 636 */ 637 static int 638 free_netcred(struct radix_node *rn, void *w) 639 { 640 struct radix_node_head *rnh = (struct radix_node_head *)w; 641 struct netcred *np = (struct netcred *)(void *)rn; 642 643 (*rnh->rnh_deladdr)(rn->rn_key, rn->rn_mask, rnh); 644 if (--(np->netc_refcnt) <= 0) { 645 KASSERT(np->netc_anon != NULL); 646 kauth_cred_free(np->netc_anon); 647 free(np, M_NETADDR); 648 } 649 return 0; 650 } 651 652 /* 653 * Clears the exports list for a given file system. 654 */ 655 static void 656 netexport_clear(struct netexport *ne) 657 { 658 struct radix_node_head *rnh; 659 struct mount *mp = ne->ne_mount; 660 int i; 661 662 if (mp->mnt_flag & MNT_EXPUBLIC) { 663 setpublicfs(NULL, NULL, NULL); 664 mp->mnt_flag &= ~MNT_EXPUBLIC; 665 } 666 667 for (i = 0; i <= AF_MAX; i++) { 668 if ((rnh = ne->ne_rtable[i]) != NULL) { 669 rn_walktree(rnh, free_netcred, rnh); 670 free(rnh, M_RTABLE); 671 ne->ne_rtable[i] = NULL; 672 } 673 } 674 675 if ((mp->mnt_flag & MNT_DEFEXPORTED) != 0) { 676 struct netcred *np = &ne->ne_defexported; 677 678 KASSERT(np->netc_anon != NULL); 679 kauth_cred_free(np->netc_anon); 680 np->netc_anon = NULL; 681 } else { 682 KASSERT(ne->ne_defexported.netc_anon == NULL); 683 } 684 685 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 686 } 687 688 /* 689 * Add a new export entry (described by an export_args structure) to the 690 * given file system. 691 */ 692 static int 693 export(struct netexport *nep, const struct export_args *argp) 694 { 695 struct mount *mp = nep->ne_mount; 696 int error; 697 698 if (argp->ex_flags & MNT_EXPORTED) { 699 if (argp->ex_flags & MNT_EXPUBLIC) { 700 if ((error = setpublicfs(mp, nep, argp)) != 0) 701 return error; 702 mp->mnt_flag |= MNT_EXPUBLIC; 703 } 704 if ((error = hang_addrlist(mp, nep, argp)) != 0) 705 return error; 706 mp->mnt_flag |= MNT_EXPORTED; 707 } 708 return 0; 709 } 710 711 /* 712 * Set the publicly exported filesystem (WebNFS). Currently, only 713 * one public filesystem is possible in the spec (RFC 2054 and 2055) 714 */ 715 static int 716 setpublicfs(struct mount *mp, struct netexport *nep, 717 const struct export_args *argp) 718 { 719 char *cp; 720 int error; 721 struct vnode *rvp; 722 size_t fhsize; 723 724 /* 725 * mp == NULL -> invalidate the current info, the FS is 726 * no longer exported. May be called from either export 727 * or unmount, so check if it hasn't already been done. 728 */ 729 if (mp == NULL) { 730 if (nfs_pub.np_valid) { 731 nfs_pub.np_valid = 0; 732 if (nfs_pub.np_handle != NULL) { 733 free(nfs_pub.np_handle, M_TEMP); 734 nfs_pub.np_handle = NULL; 735 } 736 if (nfs_pub.np_index != NULL) { 737 free(nfs_pub.np_index, M_TEMP); 738 nfs_pub.np_index = NULL; 739 } 740 } 741 return 0; 742 } 743 744 /* 745 * Only one allowed at a time. 746 */ 747 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 748 return EBUSY; 749 750 /* 751 * Get real filehandle for root of exported FS. 752 */ 753 if ((error = VFS_ROOT(mp, &rvp))) 754 return error; 755 756 fhsize = 0; 757 error = vfs_composefh(rvp, NULL, &fhsize); 758 if (error != E2BIG) 759 return error; 760 nfs_pub.np_handle = malloc(fhsize, M_TEMP, M_NOWAIT); 761 if (nfs_pub.np_handle == NULL) 762 error = ENOMEM; 763 else 764 error = vfs_composefh(rvp, nfs_pub.np_handle, &fhsize); 765 if (error) 766 return error; 767 768 vput(rvp); 769 770 /* 771 * If an indexfile was specified, pull it in. 772 */ 773 if (argp->ex_indexfile != NULL) { 774 nfs_pub.np_index = malloc(MAXNAMLEN + 1, M_TEMP, M_WAITOK); 775 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 776 MAXNAMLEN, (size_t *)0); 777 if (!error) { 778 /* 779 * Check for illegal filenames. 780 */ 781 for (cp = nfs_pub.np_index; *cp; cp++) { 782 if (*cp == '/') { 783 error = EINVAL; 784 break; 785 } 786 } 787 } 788 if (error) { 789 free(nfs_pub.np_index, M_TEMP); 790 return error; 791 } 792 } 793 794 nfs_pub.np_mount = mp; 795 nfs_pub.np_valid = 1; 796 return 0; 797 } 798 799 /* 800 * Lookup an export entry in the exports list that matches the address 801 * stored in 'nam'. If no entry is found, the default one is used instead 802 * (if available). 803 */ 804 static struct netcred * 805 netcred_lookup(struct netexport *ne, struct mbuf *nam) 806 { 807 struct netcred *np; 808 struct radix_node_head *rnh; 809 struct sockaddr *saddr; 810 811 if ((ne->ne_mount->mnt_flag & MNT_EXPORTED) == 0) { 812 return NULL; 813 } 814 815 /* 816 * Lookup in the export list first. 817 */ 818 np = NULL; 819 if (nam != NULL) { 820 saddr = mtod(nam, struct sockaddr *); 821 rnh = ne->ne_rtable[saddr->sa_family]; 822 if (rnh != NULL) { 823 np = (struct netcred *) 824 (*rnh->rnh_matchaddr)((void *)saddr, 825 rnh); 826 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 827 np = NULL; 828 } 829 } 830 /* 831 * If no address match, use the default if it exists. 832 */ 833 if (np == NULL && ne->ne_mount->mnt_flag & MNT_DEFEXPORTED) 834 np = &ne->ne_defexported; 835 836 return np; 837 } 838 839 void 840 netexport_rdlock(void) 841 { 842 843 rw_enter(&netexport_lock, RW_READER); 844 } 845 846 void 847 netexport_rdunlock(void) 848 { 849 850 rw_exit(&netexport_lock); 851 } 852 853 static void 854 netexport_wrlock(void) 855 { 856 857 rw_enter(&netexport_lock, RW_WRITER); 858 } 859 860 static void 861 netexport_wrunlock(void) 862 { 863 864 rw_exit(&netexport_lock); 865 } 866