1 /* $NetBSD: nfs_export.c,v 1.48 2009/07/07 14:09:05 christos 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 1.48 2009/07/07 14:09:05 christos 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 struct mount *nmp) 241 { 242 int error; 243 #ifdef notyet 244 /* XXX: See below to see the reason why this is disabled. */ 245 size_t i; 246 #endif 247 struct mount *mp; 248 struct netexport *ne; 249 struct nameidata nd; 250 struct vnode *vp; 251 size_t fid_size; 252 253 if (kauth_authorize_network(l->l_cred, KAUTH_NETWORK_NFS, 254 KAUTH_REQ_NETWORK_NFS_EXPORT, NULL, NULL, NULL) != 0) 255 return EPERM; 256 257 /* Lookup the file system path. */ 258 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE, mel->mel_path); 259 error = namei(&nd); 260 if (error != 0) 261 return error; 262 vp = nd.ni_vp; 263 mp = vp->v_mount; 264 KASSERT(nmp == NULL || nmp == mp); 265 266 /* 267 * Make sure the file system can do vptofh. If the file system 268 * knows the handle's size, just trust it's able to do the 269 * actual translation also (otherwise we should check fhtovp 270 * also, and that's getting a wee bit ridiculous). 271 */ 272 fid_size = 0; 273 if ((error = VFS_VPTOFH(vp, NULL, &fid_size)) != E2BIG) { 274 vput(vp); 275 return EOPNOTSUPP; 276 } 277 278 /* Mark the file system busy. */ 279 error = vfs_busy(mp, NULL); 280 vput(vp); 281 if (error != 0) 282 return error; 283 if (nmp == NULL) 284 mutex_enter(&mp->mnt_updating); /* mnt_flag */ 285 netexport_wrlock(); 286 ne = netexport_lookup(mp); 287 if (ne == NULL) { 288 error = init_exports(mp, &ne); 289 if (error != 0) { 290 goto out; 291 } 292 } 293 294 KASSERT(ne != NULL); 295 KASSERT(ne->ne_mount == mp); 296 297 /* 298 * XXX: The part marked as 'notyet' works fine from the kernel's 299 * point of view, in the sense that it is able to atomically update 300 * the complete exports list for a file system. However, supporting 301 * this in mountd(8) requires a lot of work; so, for now, keep the 302 * old behavior of updating a single entry per call. 303 * 304 * When mountd(8) is fixed, just remove the second branch of this 305 * preprocessor conditional and enable the first one. 306 */ 307 #ifdef notyet 308 netexport_clear(ne); 309 for (i = 0; error == 0 && i < mel->mel_nexports; i++) 310 error = export(ne, &mel->mel_exports[i]); 311 #else 312 if (mel->mel_nexports == 0) 313 netexport_clear(ne); 314 else if (mel->mel_nexports == 1) 315 error = export(ne, &mel->mel_exports[0]); 316 else { 317 printf("%s: Cannot set more than one " 318 "entry at once (unimplemented)\n", __func__); 319 error = EOPNOTSUPP; 320 } 321 #endif 322 323 out: 324 netexport_wrunlock(); 325 if (nmp == NULL) 326 mutex_exit(&mp->mnt_updating); /* mnt_flag */ 327 vfs_unbusy(mp, false, NULL); 328 return error; 329 } 330 331 static void 332 netexport_insert(struct netexport *ne) 333 { 334 335 CIRCLEQ_INSERT_HEAD(&netexport_list, ne, ne_list); 336 } 337 338 static void 339 netexport_remove(struct netexport *ne) 340 { 341 342 CIRCLEQ_REMOVE(&netexport_list, ne, ne_list); 343 } 344 345 static struct netexport * 346 netexport_lookup(const struct mount *mp) 347 { 348 struct netexport *ne; 349 350 CIRCLEQ_FOREACH(ne, &netexport_list, ne_list) { 351 if (ne->ne_mount == mp) { 352 goto done; 353 } 354 } 355 ne = NULL; 356 done: 357 return ne; 358 } 359 360 static struct netexport * 361 netexport_lookup_byfsid(const fsid_t *fsid) 362 { 363 struct netexport *ne; 364 365 CIRCLEQ_FOREACH(ne, &netexport_list, ne_list) { 366 const struct mount *mp = ne->ne_mount; 367 368 if (mp->mnt_stat.f_fsidx.__fsid_val[0] == fsid->__fsid_val[0] && 369 mp->mnt_stat.f_fsidx.__fsid_val[1] == fsid->__fsid_val[1]) { 370 goto done; 371 } 372 } 373 ne = NULL; 374 done: 375 376 return ne; 377 } 378 379 /* 380 * Check if the file system specified by the 'mp' mount structure is 381 * exported to a client with 'anon' anonymous credentials. The 'mb' 382 * argument is an mbuf containing the network address of the client. 383 * The return parameters for the export flags for the client are returned 384 * in the address specified by 'wh'. 385 * 386 * This function is used exclusively by the NFS server. It is generally 387 * invoked before VFS_FHTOVP to validate that client has access to the 388 * file system. 389 */ 390 391 int 392 netexport_check(const fsid_t *fsid, struct mbuf *mb, struct mount **mpp, 393 int *wh, kauth_cred_t *anon) 394 { 395 struct netexport *ne; 396 struct netcred *np; 397 398 ne = netexport_lookup_byfsid(fsid); 399 if (ne == NULL) { 400 return EACCES; 401 } 402 np = netcred_lookup(ne, mb); 403 if (np == NULL) { 404 return EACCES; 405 } 406 407 *mpp = ne->ne_mount; 408 *wh = np->netc_exflags; 409 *anon = np->netc_anon; 410 411 return 0; 412 } 413 414 /* 415 * Handles legacy export requests. In this case, the export information 416 * is hardcoded in a specific place of the mount arguments structure (given 417 * in data); the request for an update is given through the fspec field 418 * (also in a known location), which must be a null pointer. 419 * 420 * Returns EJUSTRETURN if the given command was not a export request. 421 * Otherwise, returns 0 on success or an appropriate error code otherwise. 422 */ 423 static int 424 nfs_export_update_30(struct mount *mp, const char *path, void *data) 425 { 426 struct mountd_exports_list mel; 427 struct mnt_export_args30 *args; 428 429 args = data; 430 mel.mel_path = path; 431 432 if (args->fspec != NULL) 433 return EJUSTRETURN; 434 435 if (args->eargs.ex_flags & 0x00020000) { 436 /* Request to delete exports. The mask above holds the 437 * value that used to be in MNT_DELEXPORT. */ 438 mel.mel_nexports = 0; 439 } else { 440 /* The following assumes export_args has not changed since 441 * export_args30 - typedef checks sizes. */ 442 typedef char x[sizeof args->eargs == sizeof *mel.mel_exports ? 1 : -1]; 443 444 mel.mel_nexports = 1; 445 mel.mel_exports = (void *)&args->eargs; 446 } 447 448 return mountd_set_exports_list(&mel, curlwp, mp); 449 } 450 451 /* 452 * INTERNAL FUNCTIONS 453 */ 454 455 /* 456 * Initializes NFS exports for the mountpoint given in 'mp'. 457 * If successful, returns 0 and sets *nep to the address of the new 458 * netexport item; otherwise returns an appropriate error code 459 * and *nep remains unmodified. 460 */ 461 static int 462 init_exports(struct mount *mp, struct netexport **nep) 463 { 464 int error; 465 struct export_args ea; 466 struct netexport *ne; 467 468 KASSERT(mp != NULL); 469 470 /* Ensure that we do not already have this mount point. */ 471 KASSERT(netexport_lookup(mp) == NULL); 472 473 ne = kmem_zalloc(sizeof(*ne), KM_SLEEP); 474 ne->ne_mount = mp; 475 476 /* Set the default export entry. Handled internally by export upon 477 * first call. */ 478 memset(&ea, 0, sizeof(ea)); 479 ea.ex_root = -2; 480 if (mp->mnt_flag & MNT_RDONLY) 481 ea.ex_flags |= MNT_EXRDONLY; 482 error = export(ne, &ea); 483 if (error != 0) { 484 kmem_free(ne, sizeof(*ne)); 485 } else { 486 netexport_insert(ne); 487 *nep = ne; 488 } 489 490 return error; 491 } 492 493 /* 494 * Build hash lists of net addresses and hang them off the mount point. 495 * Called by export() to set up a new entry in the lists of export 496 * addresses. 497 */ 498 static int 499 hang_addrlist(struct mount *mp, struct netexport *nep, 500 const struct export_args *argp) 501 { 502 int error, i; 503 struct netcred *np, *enp; 504 struct radix_node_head *rnh; 505 struct sockaddr *saddr, *smask; 506 struct domain *dom; 507 508 smask = NULL; 509 510 if (argp->ex_addrlen == 0) { 511 if (mp->mnt_flag & MNT_DEFEXPORTED) 512 return EPERM; 513 np = &nep->ne_defexported; 514 KASSERT(np->netc_anon == NULL); 515 np->netc_anon = kauth_cred_alloc(); 516 np->netc_exflags = argp->ex_flags; 517 kauth_uucred_to_cred(np->netc_anon, &argp->ex_anon); 518 mp->mnt_flag |= MNT_DEFEXPORTED; 519 return 0; 520 } 521 522 if (argp->ex_addrlen > MLEN || argp->ex_masklen > MLEN) 523 return EINVAL; 524 525 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 526 np = malloc(i, M_NETADDR, M_WAITOK | M_ZERO); 527 np->netc_anon = kauth_cred_alloc(); 528 saddr = (struct sockaddr *)(np + 1); 529 error = copyin(argp->ex_addr, saddr, argp->ex_addrlen); 530 if (error) 531 goto out; 532 if (saddr->sa_len > argp->ex_addrlen) 533 saddr->sa_len = argp->ex_addrlen; 534 if (sacheck(saddr) == -1) 535 return EINVAL; 536 if (argp->ex_masklen) { 537 smask = (struct sockaddr *)((char *)saddr + argp->ex_addrlen); 538 error = copyin(argp->ex_mask, smask, argp->ex_masklen); 539 if (error) 540 goto out; 541 if (smask->sa_len > argp->ex_masklen) 542 smask->sa_len = argp->ex_masklen; 543 if (smask->sa_family != saddr->sa_family) 544 return EINVAL; 545 if (sacheck(smask) == -1) 546 return EINVAL; 547 } 548 i = saddr->sa_family; 549 if ((rnh = nep->ne_rtable[i]) == 0) { 550 /* 551 * Seems silly to initialize every AF when most are not 552 * used, do so on demand here 553 */ 554 DOMAIN_FOREACH(dom) { 555 if (dom->dom_family == i && dom->dom_rtattach) { 556 dom->dom_rtattach((void **)&nep->ne_rtable[i], 557 dom->dom_rtoffset); 558 break; 559 } 560 } 561 if ((rnh = nep->ne_rtable[i]) == 0) { 562 error = ENOBUFS; 563 goto out; 564 } 565 } 566 567 enp = (struct netcred *)(*rnh->rnh_addaddr)(saddr, smask, rnh, 568 np->netc_rnodes); 569 if (enp != np) { 570 if (enp == NULL) { 571 enp = (struct netcred *)(*rnh->rnh_lookup)(saddr, 572 smask, rnh); 573 if (enp == NULL) { 574 error = EPERM; 575 goto out; 576 } 577 } else 578 enp->netc_refcnt++; 579 580 goto check; 581 } else 582 enp->netc_refcnt = 1; 583 584 np->netc_exflags = argp->ex_flags; 585 kauth_uucred_to_cred(np->netc_anon, &argp->ex_anon); 586 return 0; 587 check: 588 if (enp->netc_exflags != argp->ex_flags || 589 kauth_cred_uucmp(enp->netc_anon, &argp->ex_anon) != 0) 590 error = EPERM; 591 else 592 error = 0; 593 out: 594 KASSERT(np->netc_anon != NULL); 595 kauth_cred_free(np->netc_anon); 596 free(np, M_NETADDR); 597 return error; 598 } 599 600 /* 601 * Ensure that the address stored in 'sa' is valid. 602 * Returns zero on success, otherwise -1. 603 */ 604 static int 605 sacheck(struct sockaddr *sa) 606 { 607 608 switch (sa->sa_family) { 609 case AF_INET: { 610 struct sockaddr_in *sin = (struct sockaddr_in *)sa; 611 char *p = (char *)sin->sin_zero; 612 size_t i; 613 614 if (sin->sin_len != sizeof(*sin)) 615 return -1; 616 if (sin->sin_port != 0) 617 return -1; 618 for (i = 0; i < sizeof(sin->sin_zero); i++) 619 if (*p++ != '\0') 620 return -1; 621 return 0; 622 } 623 case AF_INET6: { 624 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa; 625 626 if (sin6->sin6_len != sizeof(*sin6)) 627 return -1; 628 if (sin6->sin6_port != 0) 629 return -1; 630 return 0; 631 } 632 default: 633 return -1; 634 } 635 } 636 637 /* 638 * Free the netcred object pointed to by the 'rn' radix node. 639 * 'w' holds a pointer to the radix tree head. 640 */ 641 static int 642 free_netcred(struct radix_node *rn, void *w) 643 { 644 struct radix_node_head *rnh = (struct radix_node_head *)w; 645 struct netcred *np = (struct netcred *)(void *)rn; 646 647 (*rnh->rnh_deladdr)(rn->rn_key, rn->rn_mask, rnh); 648 if (--(np->netc_refcnt) <= 0) { 649 KASSERT(np->netc_anon != NULL); 650 kauth_cred_free(np->netc_anon); 651 free(np, M_NETADDR); 652 } 653 return 0; 654 } 655 656 /* 657 * Clears the exports list for a given file system. 658 */ 659 static void 660 netexport_clear(struct netexport *ne) 661 { 662 struct radix_node_head *rnh; 663 struct mount *mp = ne->ne_mount; 664 int i; 665 666 if (mp->mnt_flag & MNT_EXPUBLIC) { 667 setpublicfs(NULL, NULL, NULL); 668 mp->mnt_flag &= ~MNT_EXPUBLIC; 669 } 670 671 for (i = 0; i <= AF_MAX; i++) { 672 if ((rnh = ne->ne_rtable[i]) != NULL) { 673 rn_walktree(rnh, free_netcred, rnh); 674 free(rnh, M_RTABLE); 675 ne->ne_rtable[i] = NULL; 676 } 677 } 678 679 if ((mp->mnt_flag & MNT_DEFEXPORTED) != 0) { 680 struct netcred *np = &ne->ne_defexported; 681 682 KASSERT(np->netc_anon != NULL); 683 kauth_cred_free(np->netc_anon); 684 np->netc_anon = NULL; 685 } else { 686 KASSERT(ne->ne_defexported.netc_anon == NULL); 687 } 688 689 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 690 } 691 692 /* 693 * Add a new export entry (described by an export_args structure) to the 694 * given file system. 695 */ 696 static int 697 export(struct netexport *nep, const struct export_args *argp) 698 { 699 struct mount *mp = nep->ne_mount; 700 int error; 701 702 if (argp->ex_flags & MNT_EXPORTED) { 703 if (argp->ex_flags & MNT_EXPUBLIC) { 704 if ((error = setpublicfs(mp, nep, argp)) != 0) 705 return error; 706 mp->mnt_flag |= MNT_EXPUBLIC; 707 } 708 if ((error = hang_addrlist(mp, nep, argp)) != 0) 709 return error; 710 mp->mnt_flag |= MNT_EXPORTED; 711 } 712 return 0; 713 } 714 715 /* 716 * Set the publicly exported filesystem (WebNFS). Currently, only 717 * one public filesystem is possible in the spec (RFC 2054 and 2055) 718 */ 719 static int 720 setpublicfs(struct mount *mp, struct netexport *nep, 721 const struct export_args *argp) 722 { 723 char *cp; 724 int error; 725 struct vnode *rvp; 726 size_t fhsize; 727 728 /* 729 * mp == NULL -> invalidate the current info, the FS is 730 * no longer exported. May be called from either export 731 * or unmount, so check if it hasn't already been done. 732 */ 733 if (mp == NULL) { 734 if (nfs_pub.np_valid) { 735 nfs_pub.np_valid = 0; 736 if (nfs_pub.np_handle != NULL) { 737 free(nfs_pub.np_handle, M_TEMP); 738 nfs_pub.np_handle = NULL; 739 } 740 if (nfs_pub.np_index != NULL) { 741 free(nfs_pub.np_index, M_TEMP); 742 nfs_pub.np_index = NULL; 743 } 744 } 745 return 0; 746 } 747 748 /* 749 * Only one allowed at a time. 750 */ 751 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 752 return EBUSY; 753 754 /* 755 * Get real filehandle for root of exported FS. 756 */ 757 if ((error = VFS_ROOT(mp, &rvp))) 758 return error; 759 760 fhsize = 0; 761 error = vfs_composefh(rvp, NULL, &fhsize); 762 if (error != E2BIG) 763 return error; 764 nfs_pub.np_handle = malloc(fhsize, M_TEMP, M_NOWAIT); 765 if (nfs_pub.np_handle == NULL) 766 error = ENOMEM; 767 else 768 error = vfs_composefh(rvp, nfs_pub.np_handle, &fhsize); 769 if (error) 770 return error; 771 772 vput(rvp); 773 774 /* 775 * If an indexfile was specified, pull it in. 776 */ 777 if (argp->ex_indexfile != NULL) { 778 nfs_pub.np_index = malloc(MAXNAMLEN + 1, M_TEMP, M_WAITOK); 779 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 780 MAXNAMLEN, (size_t *)0); 781 if (!error) { 782 /* 783 * Check for illegal filenames. 784 */ 785 for (cp = nfs_pub.np_index; *cp; cp++) { 786 if (*cp == '/') { 787 error = EINVAL; 788 break; 789 } 790 } 791 } 792 if (error) { 793 free(nfs_pub.np_index, M_TEMP); 794 return error; 795 } 796 } 797 798 nfs_pub.np_mount = mp; 799 nfs_pub.np_valid = 1; 800 return 0; 801 } 802 803 /* 804 * Lookup an export entry in the exports list that matches the address 805 * stored in 'nam'. If no entry is found, the default one is used instead 806 * (if available). 807 */ 808 static struct netcred * 809 netcred_lookup(struct netexport *ne, struct mbuf *nam) 810 { 811 struct netcred *np; 812 struct radix_node_head *rnh; 813 struct sockaddr *saddr; 814 815 if ((ne->ne_mount->mnt_flag & MNT_EXPORTED) == 0) { 816 return NULL; 817 } 818 819 /* 820 * Lookup in the export list first. 821 */ 822 np = NULL; 823 if (nam != NULL) { 824 saddr = mtod(nam, struct sockaddr *); 825 rnh = ne->ne_rtable[saddr->sa_family]; 826 if (rnh != NULL) { 827 np = (struct netcred *) 828 (*rnh->rnh_matchaddr)((void *)saddr, 829 rnh); 830 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 831 np = NULL; 832 } 833 } 834 /* 835 * If no address match, use the default if it exists. 836 */ 837 if (np == NULL && ne->ne_mount->mnt_flag & MNT_DEFEXPORTED) 838 np = &ne->ne_defexported; 839 840 return np; 841 } 842 843 void 844 netexport_rdlock(void) 845 { 846 847 rw_enter(&netexport_lock, RW_READER); 848 } 849 850 void 851 netexport_rdunlock(void) 852 { 853 854 rw_exit(&netexport_lock); 855 } 856 857 static void 858 netexport_wrlock(void) 859 { 860 861 rw_enter(&netexport_lock, RW_WRITER); 862 } 863 864 static void 865 netexport_wrunlock(void) 866 { 867 868 rw_exit(&netexport_lock); 869 } 870