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/socket.h> 50 #include <sys/systm.h> 51 #include <sys/vnode.h> 52 53 #include <net/radix.h> 54 55 static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 56 57 static void vfs_free_addrlist(struct netexport *nep); 58 static int vfs_free_netcred(struct radix_node *rn, void *w); 59 static int vfs_hang_addrlist(struct mount *mp, struct netexport *nep, 60 struct export_args *argp); 61 static struct netcred *vfs_export_lookup(struct mount *, struct sockaddr *); 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_family > AF_MAX) { 134 error = EINVAL; 135 goto out; 136 } 137 if (saddr->sa_len > argp->ex_addrlen) 138 saddr->sa_len = argp->ex_addrlen; 139 if (argp->ex_masklen) { 140 smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen); 141 error = copyin(argp->ex_mask, smask, argp->ex_masklen); 142 if (error) 143 goto out; 144 if (smask->sa_len > argp->ex_masklen) 145 smask->sa_len = argp->ex_masklen; 146 } 147 i = saddr->sa_family; 148 if ((rnh = nep->ne_rtable[i]) == NULL) { 149 /* 150 * Seems silly to initialize every AF when most are not used, 151 * do so on demand here 152 */ 153 for (dom = domains; dom; dom = dom->dom_next) 154 if (dom->dom_family == i && dom->dom_rtattach) { 155 dom->dom_rtattach((void **) &nep->ne_rtable[i], 156 dom->dom_rtoffset); 157 break; 158 } 159 if ((rnh = nep->ne_rtable[i]) == NULL) { 160 error = ENOBUFS; 161 goto out; 162 } 163 } 164 RADIX_NODE_HEAD_LOCK(rnh); 165 rn = (*rnh->rnh_addaddr)(saddr, smask, rnh, np->netc_rnodes); 166 RADIX_NODE_HEAD_UNLOCK(rnh); 167 if (rn == NULL || np != (struct netcred *)rn) { /* already exists */ 168 error = EPERM; 169 goto out; 170 } 171 np->netc_exflags = argp->ex_flags; 172 bzero(&np->netc_anon, sizeof(np->netc_anon)); 173 np->netc_anon.cr_uid = argp->ex_anon.cr_uid; 174 np->netc_anon.cr_ngroups = argp->ex_anon.cr_ngroups; 175 bcopy(argp->ex_anon.cr_groups, np->netc_anon.cr_groups, 176 sizeof(np->netc_anon.cr_groups)); 177 np->netc_anon.cr_ref = 1; 178 return (0); 179 out: 180 free(np, M_NETADDR); 181 return (error); 182 } 183 184 /* Helper for vfs_free_addrlist. */ 185 /* ARGSUSED */ 186 static int 187 vfs_free_netcred(rn, w) 188 struct radix_node *rn; 189 void *w; 190 { 191 register struct radix_node_head *rnh = (struct radix_node_head *) w; 192 193 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 194 free(rn, M_NETADDR); 195 return (0); 196 } 197 198 /* 199 * Free the net address hash lists that are hanging off the mount points. 200 */ 201 static void 202 vfs_free_addrlist(nep) 203 struct netexport *nep; 204 { 205 register int i; 206 register struct radix_node_head *rnh; 207 208 for (i = 0; i <= AF_MAX; i++) 209 if ((rnh = nep->ne_rtable[i])) { 210 RADIX_NODE_HEAD_LOCK(rnh); 211 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, rnh); 212 RADIX_NODE_HEAD_DESTROY(rnh); 213 free(rnh, M_RTABLE); 214 nep->ne_rtable[i] = NULL; /* not SMP safe XXX */ 215 } 216 } 217 218 /* 219 * High level function to manipulate export options on a mount point 220 * and the passed in netexport. 221 * Struct export_args *argp is the variable used to twiddle options, 222 * the structure is described in sys/mount.h 223 */ 224 int 225 vfs_export(mp, argp) 226 struct mount *mp; 227 struct export_args *argp; 228 { 229 struct netexport *nep; 230 int error; 231 232 nep = mp->mnt_export; 233 if (argp->ex_flags & MNT_DELEXPORT) { 234 if (nep == NULL) 235 return (ENOENT); 236 if (mp->mnt_flag & MNT_EXPUBLIC) { 237 vfs_setpublicfs(NULL, NULL, NULL); 238 mp->mnt_flag &= ~MNT_EXPUBLIC; 239 } 240 vfs_free_addrlist(nep); 241 mp->mnt_export = NULL; 242 free(nep, M_MOUNT); 243 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 244 } 245 if (argp->ex_flags & MNT_EXPORTED) { 246 if (nep == NULL) { 247 nep = malloc(sizeof(struct netexport), M_MOUNT, M_WAITOK | M_ZERO); 248 mp->mnt_export = nep; 249 } 250 if (argp->ex_flags & MNT_EXPUBLIC) { 251 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 252 return (error); 253 mp->mnt_flag |= MNT_EXPUBLIC; 254 } 255 if ((error = vfs_hang_addrlist(mp, nep, argp))) 256 return (error); 257 mp->mnt_flag |= MNT_EXPORTED; 258 } 259 return (0); 260 } 261 262 /* 263 * Set the publicly exported filesystem (WebNFS). Currently, only 264 * one public filesystem is possible in the spec (RFC 2054 and 2055) 265 */ 266 int 267 vfs_setpublicfs(mp, nep, argp) 268 struct mount *mp; 269 struct netexport *nep; 270 struct export_args *argp; 271 { 272 int error; 273 struct vnode *rvp; 274 char *cp; 275 276 /* 277 * mp == NULL -> invalidate the current info, the FS is 278 * no longer exported. May be called from either vfs_export 279 * or unmount, so check if it hasn't already been done. 280 */ 281 if (mp == NULL) { 282 if (nfs_pub.np_valid) { 283 nfs_pub.np_valid = 0; 284 if (nfs_pub.np_index != NULL) { 285 FREE(nfs_pub.np_index, M_TEMP); 286 nfs_pub.np_index = NULL; 287 } 288 } 289 return (0); 290 } 291 292 /* 293 * Only one allowed at a time. 294 */ 295 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 296 return (EBUSY); 297 298 /* 299 * Get real filehandle for root of exported FS. 300 */ 301 bzero(&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 302 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 303 304 if ((error = VFS_ROOT(mp, &rvp, curthread /* XXX */))) 305 return (error); 306 307 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 308 return (error); 309 310 vput(rvp); 311 312 /* 313 * If an indexfile was specified, pull it in. 314 */ 315 if (argp->ex_indexfile != NULL) { 316 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, 317 M_WAITOK); 318 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 319 MAXNAMLEN, (size_t *)0); 320 if (!error) { 321 /* 322 * Check for illegal filenames. 323 */ 324 for (cp = nfs_pub.np_index; *cp; cp++) { 325 if (*cp == '/') { 326 error = EINVAL; 327 break; 328 } 329 } 330 } 331 if (error) { 332 FREE(nfs_pub.np_index, M_TEMP); 333 return (error); 334 } 335 } 336 337 nfs_pub.np_mount = mp; 338 nfs_pub.np_valid = 1; 339 return (0); 340 } 341 342 /* 343 * Used by the filesystems to determine if a given network address 344 * (passed in 'nam') is present in thier exports list, returns a pointer 345 * to struct netcred so that the filesystem can examine it for 346 * access rights (read/write/etc). 347 */ 348 static struct netcred * 349 vfs_export_lookup(struct mount *mp, struct sockaddr *nam) 350 { 351 struct netexport *nep; 352 register struct netcred *np; 353 register struct radix_node_head *rnh; 354 struct sockaddr *saddr; 355 356 nep = mp->mnt_export; 357 if (nep == NULL) 358 return (NULL); 359 np = NULL; 360 if (mp->mnt_flag & MNT_EXPORTED) { 361 /* 362 * Lookup in the export list first. 363 */ 364 if (nam != NULL) { 365 saddr = nam; 366 rnh = nep->ne_rtable[saddr->sa_family]; 367 if (rnh != NULL) { 368 RADIX_NODE_HEAD_LOCK(rnh); 369 np = (struct netcred *) 370 (*rnh->rnh_matchaddr)(saddr, rnh); 371 RADIX_NODE_HEAD_UNLOCK(rnh); 372 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 373 np = NULL; 374 } 375 } 376 /* 377 * If no address match, use the default if it exists. 378 */ 379 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 380 np = &nep->ne_defexported; 381 } 382 return (np); 383 } 384 385 /* 386 * XXX: This comment comes from the deprecated ufs_check_export() 387 * XXX: and may not entirely apply, but lacking something better: 388 * This is the generic part of fhtovp called after the underlying 389 * filesystem has validated the file handle. 390 * 391 * Verify that a host should have access to a filesystem. 392 */ 393 394 int 395 vfs_stdcheckexp(mp, nam, extflagsp, credanonp) 396 struct mount *mp; 397 struct sockaddr *nam; 398 int *extflagsp; 399 struct ucred **credanonp; 400 { 401 struct netcred *np; 402 403 np = vfs_export_lookup(mp, nam); 404 if (np == NULL) 405 return (EACCES); 406 *extflagsp = np->netc_exflags; 407 *credanonp = &np->netc_anon; 408 return (0); 409 } 410 411