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 if (dom->dom_family == i && dom->dom_rtattach) { 166 dom->dom_rtattach((void **) &nep->ne_rtable[i], 167 dom->dom_rtoffset); 168 break; 169 } 170 if ((rnh = nep->ne_rtable[i]) == NULL) { 171 error = ENOBUFS; 172 vfs_mount_error(mp, "%s %s %d", 173 "Unable to initialize radix node head ", 174 "for address family", i); 175 goto out; 176 } 177 } 178 RADIX_NODE_HEAD_LOCK(rnh); 179 rn = (*rnh->rnh_addaddr)(saddr, smask, rnh, np->netc_rnodes); 180 RADIX_NODE_HEAD_UNLOCK(rnh); 181 if (rn == NULL || np != (struct netcred *)rn) { /* already exists */ 182 error = EPERM; 183 vfs_mount_error(mp, "Invalid radix node head, rn: %p %p", 184 rn, np); 185 goto out; 186 } 187 np->netc_exflags = argp->ex_flags; 188 bzero(&np->netc_anon, sizeof(np->netc_anon)); 189 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 190 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 191 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 192 sizeof(np->netc_anon.cr_groups)); 193 refcount_init(&np->netc_anon.cr_ref, 1); 194 return (0); 195 out: 196 free(np, M_NETADDR); 197 return (error); 198 } 199 200 /* Helper for vfs_free_addrlist. */ 201 /* ARGSUSED */ 202 static int 203 vfs_free_netcred(struct radix_node *rn, void *w) 204 { 205 register struct radix_node_head *rnh = (struct radix_node_head *) w; 206 207 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 208 free(rn, M_NETADDR); 209 return (0); 210 } 211 212 /* 213 * Free the net address hash lists that are hanging off the mount points. 214 */ 215 static void 216 vfs_free_addrlist(struct netexport *nep) 217 { 218 register int i; 219 register struct radix_node_head *rnh; 220 221 for (i = 0; i <= AF_MAX; i++) 222 if ((rnh = nep->ne_rtable[i])) { 223 RADIX_NODE_HEAD_LOCK(rnh); 224 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, rnh); 225 RADIX_NODE_HEAD_DESTROY(rnh); 226 free(rnh, M_RTABLE); 227 nep->ne_rtable[i] = NULL; /* not SMP safe XXX */ 228 } 229 } 230 231 /* 232 * High level function to manipulate export options on a mount point 233 * and the passed in netexport. 234 * Struct export_args *argp is the variable used to twiddle options, 235 * the structure is described in sys/mount.h 236 */ 237 int 238 vfs_export(struct mount *mp, struct export_args *argp) 239 { 240 struct netexport *nep; 241 int error; 242 243 nep = mp->mnt_export; 244 error = 0; 245 if (argp->ex_flags & MNT_DELEXPORT) { 246 if (nep == NULL) { 247 error = ENOENT; 248 goto out; 249 } 250 if (mp->mnt_flag & MNT_EXPUBLIC) { 251 vfs_setpublicfs(NULL, NULL, NULL); 252 MNT_ILOCK(mp); 253 mp->mnt_flag &= ~MNT_EXPUBLIC; 254 MNT_IUNLOCK(mp); 255 } 256 vfs_free_addrlist(nep); 257 mp->mnt_export = NULL; 258 free(nep, M_MOUNT); 259 nep = NULL; 260 MNT_ILOCK(mp); 261 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 262 MNT_IUNLOCK(mp); 263 } 264 if (argp->ex_flags & MNT_EXPORTED) { 265 if (nep == NULL) { 266 nep = malloc(sizeof(struct netexport), M_MOUNT, M_WAITOK | M_ZERO); 267 mp->mnt_export = nep; 268 } 269 if (argp->ex_flags & MNT_EXPUBLIC) { 270 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 271 goto out; 272 MNT_ILOCK(mp); 273 mp->mnt_flag |= MNT_EXPUBLIC; 274 MNT_IUNLOCK(mp); 275 } 276 if ((error = vfs_hang_addrlist(mp, nep, argp))) 277 goto out; 278 MNT_ILOCK(mp); 279 mp->mnt_flag |= MNT_EXPORTED; 280 MNT_IUNLOCK(mp); 281 } 282 283 out: 284 /* 285 * Once we have executed the vfs_export() command, we do 286 * not want to keep the "export" option around in the 287 * options list, since that will cause subsequent MNT_UPDATE 288 * calls to fail. The export information is saved in 289 * mp->mnt_export, so we can safely delete the "export" mount option 290 * here. 291 */ 292 vfs_deleteopt(mp->mnt_optnew, "export"); 293 vfs_deleteopt(mp->mnt_opt, "export"); 294 return (error); 295 } 296 297 /* 298 * Set the publicly exported filesystem (WebNFS). Currently, only 299 * one public filesystem is possible in the spec (RFC 2054 and 2055) 300 */ 301 int 302 vfs_setpublicfs(struct mount *mp, struct netexport *nep, 303 struct export_args *argp) 304 { 305 int error; 306 struct vnode *rvp; 307 char *cp; 308 309 /* 310 * mp == NULL -> invalidate the current info, the FS is 311 * no longer exported. May be called from either vfs_export 312 * or unmount, so check if it hasn't already been done. 313 */ 314 if (mp == NULL) { 315 if (nfs_pub.np_valid) { 316 nfs_pub.np_valid = 0; 317 if (nfs_pub.np_index != NULL) { 318 FREE(nfs_pub.np_index, M_TEMP); 319 nfs_pub.np_index = NULL; 320 } 321 } 322 return (0); 323 } 324 325 /* 326 * Only one allowed at a time. 327 */ 328 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 329 return (EBUSY); 330 331 /* 332 * Get real filehandle for root of exported FS. 333 */ 334 bzero(&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 335 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 336 337 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rvp, curthread /* XXX */))) 338 return (error); 339 340 if ((error = VOP_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 341 return (error); 342 343 vput(rvp); 344 345 /* 346 * If an indexfile was specified, pull it in. 347 */ 348 if (argp->ex_indexfile != NULL) { 349 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, 350 M_WAITOK); 351 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 352 MAXNAMLEN, (size_t *)0); 353 if (!error) { 354 /* 355 * Check for illegal filenames. 356 */ 357 for (cp = nfs_pub.np_index; *cp; cp++) { 358 if (*cp == '/') { 359 error = EINVAL; 360 break; 361 } 362 } 363 } 364 if (error) { 365 FREE(nfs_pub.np_index, M_TEMP); 366 return (error); 367 } 368 } 369 370 nfs_pub.np_mount = mp; 371 nfs_pub.np_valid = 1; 372 return (0); 373 } 374 375 /* 376 * Used by the filesystems to determine if a given network address 377 * (passed in 'nam') is present in thier exports list, returns a pointer 378 * to struct netcred so that the filesystem can examine it for 379 * access rights (read/write/etc). 380 */ 381 static struct netcred * 382 vfs_export_lookup(struct mount *mp, struct sockaddr *nam) 383 { 384 struct netexport *nep; 385 register struct netcred *np; 386 register struct radix_node_head *rnh; 387 struct sockaddr *saddr; 388 389 nep = mp->mnt_export; 390 if (nep == NULL) 391 return (NULL); 392 np = NULL; 393 if (mp->mnt_flag & MNT_EXPORTED) { 394 /* 395 * Lookup in the export list first. 396 */ 397 if (nam != NULL) { 398 saddr = nam; 399 rnh = nep->ne_rtable[saddr->sa_family]; 400 if (rnh != NULL) { 401 RADIX_NODE_HEAD_LOCK(rnh); 402 np = (struct netcred *) 403 (*rnh->rnh_matchaddr)(saddr, rnh); 404 RADIX_NODE_HEAD_UNLOCK(rnh); 405 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 406 np = NULL; 407 } 408 } 409 /* 410 * If no address match, use the default if it exists. 411 */ 412 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 413 np = &nep->ne_defexported; 414 } 415 return (np); 416 } 417 418 /* 419 * XXX: This comment comes from the deprecated ufs_check_export() 420 * XXX: and may not entirely apply, but lacking something better: 421 * This is the generic part of fhtovp called after the underlying 422 * filesystem has validated the file handle. 423 * 424 * Verify that a host should have access to a filesystem. 425 */ 426 427 int 428 vfs_stdcheckexp(struct mount *mp, struct sockaddr *nam, int *extflagsp, 429 struct ucred **credanonp) 430 { 431 struct netcred *np; 432 433 np = vfs_export_lookup(mp, nam); 434 if (np == NULL) 435 return (EACCES); 436 *extflagsp = np->netc_exflags; 437 *credanonp = &np->netc_anon; 438 return (0); 439 } 440 441