1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/dirent.h> 42 #include <sys/domain.h> 43 #include <sys/kernel.h> 44 #include <sys/lock.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/refcount.h> 50 #include <sys/socket.h> 51 #include <sys/systm.h> 52 #include <sys/vnode.h> 53 54 #include <net/radix.h> 55 56 static MALLOC_DEFINE(M_NETADDR, "export_host", "Export host address structure"); 57 58 static void vfs_free_addrlist(struct netexport *nep); 59 static int vfs_free_netcred(struct radix_node *rn, void *w); 60 static int vfs_hang_addrlist(struct mount *mp, struct netexport *nep, 61 struct export_args *argp); 62 static struct netcred *vfs_export_lookup(struct mount *, struct sockaddr *); 63 64 /* 65 * Network address lookup element 66 */ 67 struct netcred { 68 struct radix_node netc_rnodes[2]; 69 int netc_exflags; 70 struct ucred netc_anon; 71 int netc_numsecflavors; 72 int netc_secflavors[MAXSECFLAVORS]; 73 }; 74 75 /* 76 * Network export information 77 */ 78 struct netexport { 79 struct netcred ne_defexported; /* Default export */ 80 struct radix_node_head *ne_rtable[AF_MAX+1]; /* Individual exports */ 81 }; 82 83 /* 84 * Build hash lists of net addresses and hang them off the mount point. 85 * Called by ufs_mount() to set up the lists of export addresses. 86 */ 87 static int 88 vfs_hang_addrlist(struct mount *mp, struct netexport *nep, 89 struct export_args *argp) 90 { 91 register struct netcred *np; 92 register struct radix_node_head *rnh; 93 register int i; 94 struct radix_node *rn; 95 struct sockaddr *saddr, *smask = 0; 96 struct domain *dom; 97 int error; 98 99 /* 100 * XXX: This routine converts from a `struct xucred' 101 * (argp->ex_anon) to a `struct ucred' (np->netc_anon). This 102 * operation is questionable; for example, what should be done 103 * with fields like cr_uidinfo and cr_prison? Currently, this 104 * routine does not touch them (leaves them as NULL). 105 */ 106 if (argp->ex_anon.cr_version != XUCRED_VERSION) { 107 vfs_mount_error(mp, "ex_anon.cr_version: %d != %d", 108 argp->ex_anon.cr_version, XUCRED_VERSION); 109 return (EINVAL); 110 } 111 112 if (argp->ex_addrlen == 0) { 113 if (mp->mnt_flag & MNT_DEFEXPORTED) { 114 vfs_mount_error(mp, 115 "MNT_DEFEXPORTED already set for mount %p", mp); 116 return (EPERM); 117 } 118 np = &nep->ne_defexported; 119 np->netc_exflags = argp->ex_flags; 120 bzero(&np->netc_anon, sizeof(np->netc_anon)); 121 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 122 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 123 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 124 sizeof(np->netc_anon.cr_groups)); 125 np->netc_numsecflavors = argp->ex_numsecflavors; 126 bcopy(argp->ex_secflavors, np->netc_secflavors, 127 sizeof(np->netc_secflavors)); 128 refcount_init(&np->netc_anon.cr_ref, 1); 129 MNT_ILOCK(mp); 130 mp->mnt_flag |= MNT_DEFEXPORTED; 131 MNT_IUNLOCK(mp); 132 return (0); 133 } 134 135 #if MSIZE <= 256 136 if (argp->ex_addrlen > MLEN) { 137 vfs_mount_error(mp, "ex_addrlen %d is greater than %d", 138 argp->ex_addrlen, MLEN); 139 return (EINVAL); 140 } 141 #endif 142 143 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 144 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK | M_ZERO); 145 saddr = (struct sockaddr *) (np + 1); 146 if ((error = copyin(argp->ex_addr, saddr, argp->ex_addrlen))) 147 goto out; 148 if (saddr->sa_family == AF_UNSPEC || saddr->sa_family > AF_MAX) { 149 error = EINVAL; 150 vfs_mount_error(mp, "Invalid saddr->sa_family: %d"); 151 goto out; 152 } 153 if (saddr->sa_len > argp->ex_addrlen) 154 saddr->sa_len = argp->ex_addrlen; 155 if (argp->ex_masklen) { 156 smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen); 157 error = copyin(argp->ex_mask, smask, argp->ex_masklen); 158 if (error) 159 goto out; 160 if (smask->sa_len > argp->ex_masklen) 161 smask->sa_len = argp->ex_masklen; 162 } 163 i = saddr->sa_family; 164 if ((rnh = nep->ne_rtable[i]) == NULL) { 165 /* 166 * Seems silly to initialize every AF when most are not used, 167 * do so on demand here 168 */ 169 for (dom = domains; dom; dom = dom->dom_next) { 170 KASSERT(((i == AF_INET) || (i == AF_INET6)), 171 ("unexpected protocol in vfs_hang_addrlist")); 172 if (dom->dom_family == i && dom->dom_rtattach) { 173 /* 174 * XXX MRT 175 * The INET and INET6 domains know the 176 * offset already. We don't need to send it 177 * So we just use it as a flag to say that 178 * we are or are not setting up a real routing 179 * table. Only IP and IPV6 need have this 180 * be 0 so all other protocols can stay the 181 * same (ABI compatible). 182 */ 183 dom->dom_rtattach( 184 (void **) &nep->ne_rtable[i], 0); 185 break; 186 } 187 } 188 if ((rnh = nep->ne_rtable[i]) == NULL) { 189 error = ENOBUFS; 190 vfs_mount_error(mp, "%s %s %d", 191 "Unable to initialize radix node head ", 192 "for address family", i); 193 goto out; 194 } 195 } 196 RADIX_NODE_HEAD_LOCK(rnh); 197 rn = (*rnh->rnh_addaddr)(saddr, smask, rnh, np->netc_rnodes); 198 RADIX_NODE_HEAD_UNLOCK(rnh); 199 if (rn == NULL || np != (struct netcred *)rn) { /* already exists */ 200 error = EPERM; 201 vfs_mount_error(mp, "Invalid radix node head, rn: %p %p", 202 rn, np); 203 goto out; 204 } 205 np->netc_exflags = argp->ex_flags; 206 bzero(&np->netc_anon, sizeof(np->netc_anon)); 207 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 208 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 209 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 210 sizeof(np->netc_anon.cr_groups)); 211 np->netc_numsecflavors = argp->ex_numsecflavors; 212 bcopy(argp->ex_secflavors, np->netc_secflavors, 213 sizeof(np->netc_secflavors)); 214 refcount_init(&np->netc_anon.cr_ref, 1); 215 return (0); 216 out: 217 free(np, M_NETADDR); 218 return (error); 219 } 220 221 /* Helper for vfs_free_addrlist. */ 222 /* ARGSUSED */ 223 static int 224 vfs_free_netcred(struct radix_node *rn, void *w) 225 { 226 register struct radix_node_head *rnh = (struct radix_node_head *) w; 227 228 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 229 free(rn, M_NETADDR); 230 return (0); 231 } 232 233 /* 234 * Free the net address hash lists that are hanging off the mount points. 235 */ 236 static void 237 vfs_free_addrlist(struct netexport *nep) 238 { 239 register int i; 240 register struct radix_node_head *rnh; 241 242 for (i = 0; i <= AF_MAX; i++) 243 if ((rnh = nep->ne_rtable[i])) { 244 RADIX_NODE_HEAD_LOCK(rnh); 245 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, rnh); 246 RADIX_NODE_HEAD_DESTROY(rnh); 247 free(rnh, M_RTABLE); 248 nep->ne_rtable[i] = NULL; /* not SMP safe XXX */ 249 } 250 } 251 252 /* 253 * High level function to manipulate export options on a mount point 254 * and the passed in netexport. 255 * Struct export_args *argp is the variable used to twiddle options, 256 * the structure is described in sys/mount.h 257 */ 258 int 259 vfs_export(struct mount *mp, struct export_args *argp) 260 { 261 struct netexport *nep; 262 int error; 263 264 if (argp->ex_numsecflavors < 0 265 || argp->ex_numsecflavors >= MAXSECFLAVORS) 266 return (EINVAL); 267 268 nep = mp->mnt_export; 269 error = 0; 270 lockmgr(&mp->mnt_explock, LK_EXCLUSIVE, NULL); 271 if (argp->ex_flags & MNT_DELEXPORT) { 272 if (nep == NULL) { 273 error = ENOENT; 274 goto out; 275 } 276 if (mp->mnt_flag & MNT_EXPUBLIC) { 277 vfs_setpublicfs(NULL, NULL, NULL); 278 MNT_ILOCK(mp); 279 mp->mnt_flag &= ~MNT_EXPUBLIC; 280 MNT_IUNLOCK(mp); 281 } 282 vfs_free_addrlist(nep); 283 mp->mnt_export = NULL; 284 free(nep, M_MOUNT); 285 nep = NULL; 286 MNT_ILOCK(mp); 287 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 288 MNT_IUNLOCK(mp); 289 } 290 if (argp->ex_flags & MNT_EXPORTED) { 291 if (nep == NULL) { 292 nep = malloc(sizeof(struct netexport), M_MOUNT, M_WAITOK | M_ZERO); 293 mp->mnt_export = nep; 294 } 295 if (argp->ex_flags & MNT_EXPUBLIC) { 296 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 297 goto out; 298 MNT_ILOCK(mp); 299 mp->mnt_flag |= MNT_EXPUBLIC; 300 MNT_IUNLOCK(mp); 301 } 302 if ((error = vfs_hang_addrlist(mp, nep, argp))) 303 goto out; 304 MNT_ILOCK(mp); 305 mp->mnt_flag |= MNT_EXPORTED; 306 MNT_IUNLOCK(mp); 307 } 308 309 out: 310 lockmgr(&mp->mnt_explock, LK_RELEASE, NULL); 311 /* 312 * Once we have executed the vfs_export() command, we do 313 * not want to keep the "export" option around in the 314 * options list, since that will cause subsequent MNT_UPDATE 315 * calls to fail. The export information is saved in 316 * mp->mnt_export, so we can safely delete the "export" mount option 317 * here. 318 */ 319 vfs_deleteopt(mp->mnt_optnew, "export"); 320 vfs_deleteopt(mp->mnt_opt, "export"); 321 return (error); 322 } 323 324 /* 325 * Set the publicly exported filesystem (WebNFS). Currently, only 326 * one public filesystem is possible in the spec (RFC 2054 and 2055) 327 */ 328 int 329 vfs_setpublicfs(struct mount *mp, struct netexport *nep, 330 struct export_args *argp) 331 { 332 int error; 333 struct vnode *rvp; 334 char *cp; 335 336 /* 337 * mp == NULL -> invalidate the current info, the FS is 338 * no longer exported. May be called from either vfs_export 339 * or unmount, so check if it hasn't already been done. 340 */ 341 if (mp == NULL) { 342 if (nfs_pub.np_valid) { 343 nfs_pub.np_valid = 0; 344 if (nfs_pub.np_index != NULL) { 345 free(nfs_pub.np_index, M_TEMP); 346 nfs_pub.np_index = NULL; 347 } 348 } 349 return (0); 350 } 351 352 /* 353 * Only one allowed at a time. 354 */ 355 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 356 return (EBUSY); 357 358 /* 359 * Get real filehandle for root of exported FS. 360 */ 361 bzero(&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 362 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 363 364 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rvp, curthread /* XXX */))) 365 return (error); 366 367 if ((error = VOP_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 368 return (error); 369 370 vput(rvp); 371 372 /* 373 * If an indexfile was specified, pull it in. 374 */ 375 if (argp->ex_indexfile != NULL) { 376 nfs_pub.np_index = malloc(MAXNAMLEN + 1, M_TEMP, 377 M_WAITOK); 378 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 379 MAXNAMLEN, (size_t *)0); 380 if (!error) { 381 /* 382 * Check for illegal filenames. 383 */ 384 for (cp = nfs_pub.np_index; *cp; cp++) { 385 if (*cp == '/') { 386 error = EINVAL; 387 break; 388 } 389 } 390 } 391 if (error) { 392 free(nfs_pub.np_index, M_TEMP); 393 return (error); 394 } 395 } 396 397 nfs_pub.np_mount = mp; 398 nfs_pub.np_valid = 1; 399 return (0); 400 } 401 402 /* 403 * Used by the filesystems to determine if a given network address 404 * (passed in 'nam') is present in their exports list, returns a pointer 405 * to struct netcred so that the filesystem can examine it for 406 * access rights (read/write/etc). 407 */ 408 static struct netcred * 409 vfs_export_lookup(struct mount *mp, struct sockaddr *nam) 410 { 411 struct netexport *nep; 412 register struct netcred *np; 413 register struct radix_node_head *rnh; 414 struct sockaddr *saddr; 415 416 nep = mp->mnt_export; 417 if (nep == NULL) 418 return (NULL); 419 np = NULL; 420 if (mp->mnt_flag & MNT_EXPORTED) { 421 /* 422 * Lookup in the export list first. 423 */ 424 if (nam != NULL) { 425 saddr = nam; 426 rnh = nep->ne_rtable[saddr->sa_family]; 427 if (rnh != NULL) { 428 RADIX_NODE_HEAD_LOCK(rnh); 429 np = (struct netcred *) 430 (*rnh->rnh_matchaddr)(saddr, rnh); 431 RADIX_NODE_HEAD_UNLOCK(rnh); 432 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 433 np = NULL; 434 } 435 } 436 /* 437 * If no address match, use the default if it exists. 438 */ 439 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 440 np = &nep->ne_defexported; 441 } 442 return (np); 443 } 444 445 /* 446 * XXX: This comment comes from the deprecated ufs_check_export() 447 * XXX: and may not entirely apply, but lacking something better: 448 * This is the generic part of fhtovp called after the underlying 449 * filesystem has validated the file handle. 450 * 451 * Verify that a host should have access to a filesystem. 452 */ 453 454 int 455 vfs_stdcheckexp(struct mount *mp, struct sockaddr *nam, int *extflagsp, 456 struct ucred **credanonp, int *numsecflavors, int **secflavors) 457 { 458 struct netcred *np; 459 460 lockmgr(&mp->mnt_explock, LK_SHARED, NULL); 461 np = vfs_export_lookup(mp, nam); 462 lockmgr(&mp->mnt_explock, LK_RELEASE, NULL); 463 if (np == NULL) 464 return (EACCES); 465 *extflagsp = np->netc_exflags; 466 *credanonp = &np->netc_anon; 467 if (numsecflavors) 468 *numsecflavors = np->netc_numsecflavors; 469 if (secflavors) 470 *secflavors = np->netc_secflavors; 471 return (0); 472 } 473 474