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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/socket.h> 48 #include <sys/malloc.h> 49 #include <sys/mbuf.h> 50 #include <sys/mount.h> 51 #include <net/radix.h> 52 #include <sys/domain.h> 53 #include <sys/dirent.h> 54 #include <sys/vnode.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 63 /* 64 * Network address lookup element 65 */ 66 struct netcred { 67 struct radix_node netc_rnodes[2]; 68 int netc_exflags; 69 struct ucred netc_anon; 70 }; 71 72 /* 73 * Network export information 74 */ 75 struct netexport { 76 struct netcred ne_defexported; /* Default export */ 77 struct radix_node_head *ne_rtable[AF_MAX+1]; /* Individual exports */ 78 }; 79 80 /* 81 * Build hash lists of net addresses and hang them off the mount point. 82 * Called by ufs_mount() to set up the lists of export addresses. 83 */ 84 static int 85 vfs_hang_addrlist(mp, nep, argp) 86 struct mount *mp; 87 struct netexport *nep; 88 struct export_args *argp; 89 { 90 register struct netcred *np; 91 register struct radix_node_head *rnh; 92 register int i; 93 struct radix_node *rn; 94 struct sockaddr *saddr, *smask = 0; 95 struct domain *dom; 96 int error; 97 98 /* 99 * XXX: This routine converts from a `struct xucred' 100 * (argp->ex_anon) to a `struct ucred' (np->netc_anon). This 101 * operation is questionable; for example, what should be done 102 * with fields like cr_uidinfo and cr_prison? Currently, this 103 * routine does not touch them (leaves them as NULL). 104 */ 105 if (argp->ex_anon.cr_version != XUCRED_VERSION) 106 return (EINVAL); 107 108 if (argp->ex_addrlen == 0) { 109 if (mp->mnt_flag & MNT_DEFEXPORTED) 110 return (EPERM); 111 np = &nep->ne_defexported; 112 np->netc_exflags = argp->ex_flags; 113 bzero(&np->netc_anon, sizeof(np->netc_anon)); 114 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 115 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 116 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 117 sizeof(np->netc_anon.cr_groups)); 118 np->netc_anon.cr_ref = 1; 119 mp->mnt_flag |= MNT_DEFEXPORTED; 120 return (0); 121 } 122 123 #if MSIZE <= 256 124 if (argp->ex_addrlen > MLEN) 125 return (EINVAL); 126 #endif 127 128 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 129 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK | M_ZERO); 130 saddr = (struct sockaddr *) (np + 1); 131 if ((error = copyin(argp->ex_addr, saddr, argp->ex_addrlen))) 132 goto out; 133 if (saddr->sa_len > argp->ex_addrlen) 134 saddr->sa_len = argp->ex_addrlen; 135 if (argp->ex_masklen) { 136 smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen); 137 error = copyin(argp->ex_mask, smask, argp->ex_masklen); 138 if (error) 139 goto out; 140 if (smask->sa_len > argp->ex_masklen) 141 smask->sa_len = argp->ex_masklen; 142 } 143 i = saddr->sa_family; 144 if ((rnh = nep->ne_rtable[i]) == NULL) { 145 /* 146 * Seems silly to initialize every AF when most are not used, 147 * do so on demand here 148 */ 149 for (dom = domains; dom; dom = dom->dom_next) 150 if (dom->dom_family == i && dom->dom_rtattach) { 151 dom->dom_rtattach((void **) &nep->ne_rtable[i], 152 dom->dom_rtoffset); 153 break; 154 } 155 if ((rnh = nep->ne_rtable[i]) == NULL) { 156 error = ENOBUFS; 157 goto out; 158 } 159 } 160 RADIX_NODE_HEAD_LOCK(rnh); 161 rn = (*rnh->rnh_addaddr)(saddr, smask, rnh, np->netc_rnodes); 162 RADIX_NODE_HEAD_UNLOCK(rnh); 163 if (rn == NULL || np != (struct netcred *)rn) { /* already exists */ 164 error = EPERM; 165 goto out; 166 } 167 np->netc_exflags = argp->ex_flags; 168 bzero(&np->netc_anon, sizeof(np->netc_anon)); 169 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 170 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 171 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 172 sizeof(np->netc_anon.cr_groups)); 173 np->netc_anon.cr_ref = 1; 174 return (0); 175 out: 176 free(np, M_NETADDR); 177 return (error); 178 } 179 180 /* Helper for vfs_free_addrlist. */ 181 /* ARGSUSED */ 182 static int 183 vfs_free_netcred(rn, w) 184 struct radix_node *rn; 185 void *w; 186 { 187 register struct radix_node_head *rnh = (struct radix_node_head *) w; 188 189 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 190 free(rn, M_NETADDR); 191 return (0); 192 } 193 194 /* 195 * Free the net address hash lists that are hanging off the mount points. 196 */ 197 static void 198 vfs_free_addrlist(nep) 199 struct netexport *nep; 200 { 201 register int i; 202 register struct radix_node_head *rnh; 203 204 for (i = 0; i <= AF_MAX; i++) 205 if ((rnh = nep->ne_rtable[i])) { 206 RADIX_NODE_HEAD_LOCK(rnh); 207 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, rnh); 208 RADIX_NODE_HEAD_DESTROY(rnh); 209 free(rnh, M_RTABLE); 210 nep->ne_rtable[i] = NULL; /* not SMP safe XXX */ 211 } 212 } 213 214 /* 215 * High level function to manipulate export options on a mount point 216 * and the passed in netexport. 217 * Struct export_args *argp is the variable used to twiddle options, 218 * the structure is described in sys/mount.h 219 */ 220 int 221 vfs_export(mp, argp) 222 struct mount *mp; 223 struct export_args *argp; 224 { 225 struct netexport *nep; 226 int error; 227 228 nep = mp->mnt_export; 229 if (argp->ex_flags & MNT_DELEXPORT) { 230 if (nep == NULL) 231 return (ENOENT); 232 if (mp->mnt_flag & MNT_EXPUBLIC) { 233 vfs_setpublicfs(NULL, NULL, NULL); 234 mp->mnt_flag &= ~MNT_EXPUBLIC; 235 } 236 vfs_free_addrlist(nep); 237 mp->mnt_export = NULL; 238 free(nep, M_MOUNT); 239 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 240 } 241 if (argp->ex_flags & MNT_EXPORTED) { 242 if (nep == NULL) { 243 nep = malloc(sizeof(struct netexport), M_MOUNT, M_WAITOK | M_ZERO); 244 mp->mnt_export = nep; 245 } 246 if (argp->ex_flags & MNT_EXPUBLIC) { 247 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 248 return (error); 249 mp->mnt_flag |= MNT_EXPUBLIC; 250 } 251 if ((error = vfs_hang_addrlist(mp, nep, argp))) 252 return (error); 253 mp->mnt_flag |= MNT_EXPORTED; 254 } 255 return (0); 256 } 257 258 /* 259 * Set the publicly exported filesystem (WebNFS). Currently, only 260 * one public filesystem is possible in the spec (RFC 2054 and 2055) 261 */ 262 int 263 vfs_setpublicfs(mp, nep, argp) 264 struct mount *mp; 265 struct netexport *nep; 266 struct export_args *argp; 267 { 268 int error; 269 struct vnode *rvp; 270 char *cp; 271 272 /* 273 * mp == NULL -> invalidate the current info, the FS is 274 * no longer exported. May be called from either vfs_export 275 * or unmount, so check if it hasn't already been done. 276 */ 277 if (mp == NULL) { 278 if (nfs_pub.np_valid) { 279 nfs_pub.np_valid = 0; 280 if (nfs_pub.np_index != NULL) { 281 FREE(nfs_pub.np_index, M_TEMP); 282 nfs_pub.np_index = NULL; 283 } 284 } 285 return (0); 286 } 287 288 /* 289 * Only one allowed at a time. 290 */ 291 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 292 return (EBUSY); 293 294 /* 295 * Get real filehandle for root of exported FS. 296 */ 297 bzero(&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 298 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 299 300 if ((error = VFS_ROOT(mp, &rvp))) 301 return (error); 302 303 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 304 return (error); 305 306 vput(rvp); 307 308 /* 309 * If an indexfile was specified, pull it in. 310 */ 311 if (argp->ex_indexfile != NULL) { 312 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, 313 M_WAITOK); 314 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 315 MAXNAMLEN, (size_t *)0); 316 if (!error) { 317 /* 318 * Check for illegal filenames. 319 */ 320 for (cp = nfs_pub.np_index; *cp; cp++) { 321 if (*cp == '/') { 322 error = EINVAL; 323 break; 324 } 325 } 326 } 327 if (error) { 328 FREE(nfs_pub.np_index, M_TEMP); 329 return (error); 330 } 331 } 332 333 nfs_pub.np_mount = mp; 334 nfs_pub.np_valid = 1; 335 return (0); 336 } 337 338 /* 339 * Used by the filesystems to determine if a given network address 340 * (passed in 'nam') is present in thier exports list, returns a pointer 341 * to struct netcred so that the filesystem can examine it for 342 * access rights (read/write/etc). 343 */ 344 struct netcred * 345 vfs_export_lookup(mp, nam) 346 register struct mount *mp; 347 struct sockaddr *nam; 348 { 349 struct netexport *nep; 350 register struct netcred *np; 351 register struct radix_node_head *rnh; 352 struct sockaddr *saddr; 353 354 nep = mp->mnt_export; 355 if (nep == NULL) 356 return (NULL); 357 np = NULL; 358 if (mp->mnt_flag & MNT_EXPORTED) { 359 /* 360 * Lookup in the export list first. 361 */ 362 if (nam != NULL) { 363 saddr = nam; 364 rnh = nep->ne_rtable[saddr->sa_family]; 365 if (rnh != NULL) { 366 RADIX_NODE_HEAD_LOCK(rnh); 367 np = (struct netcred *) 368 (*rnh->rnh_matchaddr)(saddr, rnh); 369 RADIX_NODE_HEAD_UNLOCK(rnh); 370 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 371 np = NULL; 372 } 373 } 374 /* 375 * If no address match, use the default if it exists. 376 */ 377 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 378 np = &nep->ne_defexported; 379 } 380 return (np); 381 } 382 383 /* 384 * XXX: This comment comes from the deprecated ufs_check_export() 385 * XXX: and may not entirely apply, but lacking something better: 386 * This is the generic part of fhtovp called after the underlying 387 * filesystem has validated the file handle. 388 * 389 * Verify that a host should have access to a filesystem. 390 */ 391 392 int 393 vfs_stdcheckexp(mp, nam, extflagsp, credanonp) 394 struct mount *mp; 395 struct sockaddr *nam; 396 int *extflagsp; 397 struct ucred **credanonp; 398 { 399 struct netcred *np; 400 401 np = vfs_export_lookup(mp, nam); 402 if (np == NULL) 403 return (EACCES); 404 *extflagsp = np->netc_exflags; 405 *credanonp = &np->netc_anon; 406 return (0); 407 } 408 409