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 }; 72 73 /* 74 * Network export information 75 */ 76 struct netexport { 77 struct netcred ne_defexported; /* Default export */ 78 struct radix_node_head *ne_rtable[AF_MAX+1]; /* Individual exports */ 79 }; 80 81 /* 82 * Build hash lists of net addresses and hang them off the mount point. 83 * Called by ufs_mount() to set up the lists of export addresses. 84 */ 85 static int 86 vfs_hang_addrlist(struct mount *mp, struct netexport *nep, 87 struct export_args *argp) 88 { 89 register struct netcred *np; 90 register struct radix_node_head *rnh; 91 register int i; 92 struct radix_node *rn; 93 struct sockaddr *saddr, *smask = 0; 94 struct domain *dom; 95 int error; 96 97 /* 98 * XXX: This routine converts from a `struct xucred' 99 * (argp->ex_anon) to a `struct ucred' (np->netc_anon). This 100 * operation is questionable; for example, what should be done 101 * with fields like cr_uidinfo and cr_prison? Currently, this 102 * routine does not touch them (leaves them as NULL). 103 */ 104 if (argp->ex_anon.cr_version != XUCRED_VERSION) { 105 vfs_mount_error(mp, "ex_anon.cr_version: %d != %d", 106 argp->ex_anon.cr_version, XUCRED_VERSION); 107 return (EINVAL); 108 } 109 110 if (argp->ex_addrlen == 0) { 111 if (mp->mnt_flag & MNT_DEFEXPORTED) { 112 vfs_mount_error(mp, 113 "MNT_DEFEXPORTED already set for mount %p", mp); 114 return (EPERM); 115 } 116 np = &nep->ne_defexported; 117 np->netc_exflags = argp->ex_flags; 118 bzero(&np->netc_anon, sizeof(np->netc_anon)); 119 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 120 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 121 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 122 sizeof(np->netc_anon.cr_groups)); 123 refcount_init(&np->netc_anon.cr_ref, 1); 124 MNT_ILOCK(mp); 125 mp->mnt_flag |= MNT_DEFEXPORTED; 126 MNT_IUNLOCK(mp); 127 return (0); 128 } 129 130 #if MSIZE <= 256 131 if (argp->ex_addrlen > MLEN) { 132 vfs_mount_error(mp, "ex_addrlen %d is greater than %d", 133 argp->ex_addrlen, MLEN); 134 return (EINVAL); 135 } 136 #endif 137 138 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 139 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK | M_ZERO); 140 saddr = (struct sockaddr *) (np + 1); 141 if ((error = copyin(argp->ex_addr, saddr, argp->ex_addrlen))) 142 goto out; 143 if (saddr->sa_family == AF_UNSPEC || saddr->sa_family > AF_MAX) { 144 error = EINVAL; 145 vfs_mount_error(mp, "Invalid saddr->sa_family: %d"); 146 goto out; 147 } 148 if (saddr->sa_len > argp->ex_addrlen) 149 saddr->sa_len = argp->ex_addrlen; 150 if (argp->ex_masklen) { 151 smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen); 152 error = copyin(argp->ex_mask, smask, argp->ex_masklen); 153 if (error) 154 goto out; 155 if (smask->sa_len > argp->ex_masklen) 156 smask->sa_len = argp->ex_masklen; 157 } 158 i = saddr->sa_family; 159 if ((rnh = nep->ne_rtable[i]) == NULL) { 160 /* 161 * Seems silly to initialize every AF when most are not used, 162 * do so on demand here 163 */ 164 for (dom = domains; dom; dom = dom->dom_next) { 165 KASSERT(((i == AF_INET) || (i == AF_INET6)), 166 ("unexpected protocol in vfs_hang_addrlist")); 167 if (dom->dom_family == i && dom->dom_rtattach) { 168 /* 169 * XXX MRT 170 * The INET and INET6 domains know the 171 * offset already. We don't need to send it 172 * So we just use it as a flag to say that 173 * we are or are not setting up a real routing 174 * table. Only IP and IPV6 need have this 175 * be 0 so all other protocols can stay the 176 * same (ABI compatible). 177 */ 178 dom->dom_rtattach( 179 (void **) &nep->ne_rtable[i], 0); 180 break; 181 } 182 } 183 if ((rnh = nep->ne_rtable[i]) == NULL) { 184 error = ENOBUFS; 185 vfs_mount_error(mp, "%s %s %d", 186 "Unable to initialize radix node head ", 187 "for address family", i); 188 goto out; 189 } 190 } 191 RADIX_NODE_HEAD_LOCK(rnh); 192 rn = (*rnh->rnh_addaddr)(saddr, smask, rnh, np->netc_rnodes); 193 RADIX_NODE_HEAD_UNLOCK(rnh); 194 if (rn == NULL || np != (struct netcred *)rn) { /* already exists */ 195 error = EPERM; 196 vfs_mount_error(mp, "Invalid radix node head, rn: %p %p", 197 rn, np); 198 goto out; 199 } 200 np->netc_exflags = argp->ex_flags; 201 bzero(&np->netc_anon, sizeof(np->netc_anon)); 202 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 203 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 204 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 205 sizeof(np->netc_anon.cr_groups)); 206 refcount_init(&np->netc_anon.cr_ref, 1); 207 return (0); 208 out: 209 free(np, M_NETADDR); 210 return (error); 211 } 212 213 /* Helper for vfs_free_addrlist. */ 214 /* ARGSUSED */ 215 static int 216 vfs_free_netcred(struct radix_node *rn, void *w) 217 { 218 register struct radix_node_head *rnh = (struct radix_node_head *) w; 219 220 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 221 free(rn, M_NETADDR); 222 return (0); 223 } 224 225 /* 226 * Free the net address hash lists that are hanging off the mount points. 227 */ 228 static void 229 vfs_free_addrlist(struct netexport *nep) 230 { 231 register int i; 232 register struct radix_node_head *rnh; 233 234 for (i = 0; i <= AF_MAX; i++) 235 if ((rnh = nep->ne_rtable[i])) { 236 RADIX_NODE_HEAD_LOCK(rnh); 237 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, rnh); 238 RADIX_NODE_HEAD_DESTROY(rnh); 239 free(rnh, M_RTABLE); 240 nep->ne_rtable[i] = NULL; /* not SMP safe XXX */ 241 } 242 } 243 244 /* 245 * High level function to manipulate export options on a mount point 246 * and the passed in netexport. 247 * Struct export_args *argp is the variable used to twiddle options, 248 * the structure is described in sys/mount.h 249 */ 250 int 251 vfs_export(struct mount *mp, struct export_args *argp) 252 { 253 struct netexport *nep; 254 int error; 255 256 nep = mp->mnt_export; 257 error = 0; 258 lockmgr(&mp->mnt_explock, LK_EXCLUSIVE, NULL); 259 if (argp->ex_flags & MNT_DELEXPORT) { 260 if (nep == NULL) { 261 error = ENOENT; 262 goto out; 263 } 264 if (mp->mnt_flag & MNT_EXPUBLIC) { 265 vfs_setpublicfs(NULL, NULL, NULL); 266 MNT_ILOCK(mp); 267 mp->mnt_flag &= ~MNT_EXPUBLIC; 268 MNT_IUNLOCK(mp); 269 } 270 vfs_free_addrlist(nep); 271 mp->mnt_export = NULL; 272 free(nep, M_MOUNT); 273 nep = NULL; 274 MNT_ILOCK(mp); 275 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 276 MNT_IUNLOCK(mp); 277 } 278 if (argp->ex_flags & MNT_EXPORTED) { 279 if (nep == NULL) { 280 nep = malloc(sizeof(struct netexport), M_MOUNT, M_WAITOK | M_ZERO); 281 mp->mnt_export = nep; 282 } 283 if (argp->ex_flags & MNT_EXPUBLIC) { 284 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 285 goto out; 286 MNT_ILOCK(mp); 287 mp->mnt_flag |= MNT_EXPUBLIC; 288 MNT_IUNLOCK(mp); 289 } 290 if ((error = vfs_hang_addrlist(mp, nep, argp))) 291 goto out; 292 MNT_ILOCK(mp); 293 mp->mnt_flag |= MNT_EXPORTED; 294 MNT_IUNLOCK(mp); 295 } 296 297 out: 298 lockmgr(&mp->mnt_explock, LK_RELEASE, NULL); 299 /* 300 * Once we have executed the vfs_export() command, we do 301 * not want to keep the "export" option around in the 302 * options list, since that will cause subsequent MNT_UPDATE 303 * calls to fail. The export information is saved in 304 * mp->mnt_export, so we can safely delete the "export" mount option 305 * here. 306 */ 307 vfs_deleteopt(mp->mnt_optnew, "export"); 308 vfs_deleteopt(mp->mnt_opt, "export"); 309 return (error); 310 } 311 312 /* 313 * Set the publicly exported filesystem (WebNFS). Currently, only 314 * one public filesystem is possible in the spec (RFC 2054 and 2055) 315 */ 316 int 317 vfs_setpublicfs(struct mount *mp, struct netexport *nep, 318 struct export_args *argp) 319 { 320 int error; 321 struct vnode *rvp; 322 char *cp; 323 324 /* 325 * mp == NULL -> invalidate the current info, the FS is 326 * no longer exported. May be called from either vfs_export 327 * or unmount, so check if it hasn't already been done. 328 */ 329 if (mp == NULL) { 330 if (nfs_pub.np_valid) { 331 nfs_pub.np_valid = 0; 332 if (nfs_pub.np_index != NULL) { 333 FREE(nfs_pub.np_index, M_TEMP); 334 nfs_pub.np_index = NULL; 335 } 336 } 337 return (0); 338 } 339 340 /* 341 * Only one allowed at a time. 342 */ 343 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 344 return (EBUSY); 345 346 /* 347 * Get real filehandle for root of exported FS. 348 */ 349 bzero(&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 350 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 351 352 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rvp, curthread /* XXX */))) 353 return (error); 354 355 if ((error = VOP_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 356 return (error); 357 358 vput(rvp); 359 360 /* 361 * If an indexfile was specified, pull it in. 362 */ 363 if (argp->ex_indexfile != NULL) { 364 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, 365 M_WAITOK); 366 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 367 MAXNAMLEN, (size_t *)0); 368 if (!error) { 369 /* 370 * Check for illegal filenames. 371 */ 372 for (cp = nfs_pub.np_index; *cp; cp++) { 373 if (*cp == '/') { 374 error = EINVAL; 375 break; 376 } 377 } 378 } 379 if (error) { 380 FREE(nfs_pub.np_index, M_TEMP); 381 return (error); 382 } 383 } 384 385 nfs_pub.np_mount = mp; 386 nfs_pub.np_valid = 1; 387 return (0); 388 } 389 390 /* 391 * Used by the filesystems to determine if a given network address 392 * (passed in 'nam') is present in thier exports list, returns a pointer 393 * to struct netcred so that the filesystem can examine it for 394 * access rights (read/write/etc). 395 */ 396 static struct netcred * 397 vfs_export_lookup(struct mount *mp, struct sockaddr *nam) 398 { 399 struct netexport *nep; 400 register struct netcred *np; 401 register struct radix_node_head *rnh; 402 struct sockaddr *saddr; 403 404 nep = mp->mnt_export; 405 if (nep == NULL) 406 return (NULL); 407 np = NULL; 408 if (mp->mnt_flag & MNT_EXPORTED) { 409 /* 410 * Lookup in the export list first. 411 */ 412 if (nam != NULL) { 413 saddr = nam; 414 rnh = nep->ne_rtable[saddr->sa_family]; 415 if (rnh != NULL) { 416 RADIX_NODE_HEAD_LOCK(rnh); 417 np = (struct netcred *) 418 (*rnh->rnh_matchaddr)(saddr, rnh); 419 RADIX_NODE_HEAD_UNLOCK(rnh); 420 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 421 np = NULL; 422 } 423 } 424 /* 425 * If no address match, use the default if it exists. 426 */ 427 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 428 np = &nep->ne_defexported; 429 } 430 return (np); 431 } 432 433 /* 434 * XXX: This comment comes from the deprecated ufs_check_export() 435 * XXX: and may not entirely apply, but lacking something better: 436 * This is the generic part of fhtovp called after the underlying 437 * filesystem has validated the file handle. 438 * 439 * Verify that a host should have access to a filesystem. 440 */ 441 442 int 443 vfs_stdcheckexp(struct mount *mp, struct sockaddr *nam, int *extflagsp, 444 struct ucred **credanonp) 445 { 446 struct netcred *np; 447 448 lockmgr(&mp->mnt_explock, LK_SHARED, NULL); 449 np = vfs_export_lookup(mp, nam); 450 lockmgr(&mp->mnt_explock, LK_RELEASE, NULL); 451 if (np == NULL) 452 return (EACCES); 453 *extflagsp = np->netc_exflags; 454 *credanonp = &np->netc_anon; 455 return (0); 456 } 457 458