/*-
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/dirent.h>
#include <sys/jail.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/rwlock.h>
#include <sys/refcount.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <netinet/in.h>
#include <net/radix.h>
static MALLOC_DEFINE(M_NETADDR, "export_host", "Export host address structure");
#if defined(INET) || defined(INET6)
static struct radix_node_head *vfs_create_addrlist_af(
struct radix_node_head **prnh, int off);
#endif
static void vfs_free_addrlist(struct netexport *nep);
static int vfs_free_netcred(struct radix_node *rn, void *w);
static void vfs_free_addrlist_af(struct radix_node_head **prnh);
static int vfs_hang_addrlist(struct mount *mp, struct netexport *nep,
struct export_args *argp);
static struct netcred *vfs_export_lookup(struct mount *, struct sockaddr *);
/*
* Network address lookup element
*/
struct netcred {
struct radix_node netc_rnodes[2];
int netc_exflags;
struct ucred *netc_anon;
int netc_numsecflavors;
int netc_secflavors[MAXSECFLAVORS];
};
/*
* Network export information
*/
struct netexport {
struct netcred ne_defexported; /* Default export */
struct radix_node_head *ne4;
struct radix_node_head *ne6;
};
/*
* Build hash lists of net addresses and hang them off the mount point.
* Called by vfs_export() to set up the lists of export addresses.
*/
static int
vfs_hang_addrlist(struct mount *mp, struct netexport *nep,
struct export_args *argp)
{
struct netcred *np;
struct radix_node_head *rnh;
int i;
struct radix_node *rn;
struct sockaddr *saddr, *smask = NULL;
#if defined(INET6) || defined(INET)
int off;
#endif
int error;
/*
* XXX: This routine converts from a `struct xucred'
* (argp->ex_anon) to a `struct ucred' (np->netc_anon). This
* operation is questionable; for example, what should be done
* with fields like cr_uidinfo and cr_prison? Currently, this
* routine does not touch them (leaves them as NULL).
*/
if (argp->ex_anon.cr_version != XUCRED_VERSION) {
vfs_mount_error(mp, "ex_anon.cr_version: %d != %d",
argp->ex_anon.cr_version, XUCRED_VERSION);
return (EINVAL);
}
if (argp->ex_addrlen == 0) {
if (mp->mnt_flag & MNT_DEFEXPORTED) {
vfs_mount_error(mp,
"MNT_DEFEXPORTED already set for mount %p", mp);
return (EPERM);
}
np = &nep->ne_defexported;
np->netc_exflags = argp->ex_flags;
np->netc_anon = crget();
np->netc_anon->cr_uid = argp->ex_anon.cr_uid;
crsetgroups(np->netc_anon, argp->ex_anon.cr_ngroups,
argp->ex_anon.cr_groups);
np->netc_anon->cr_prison = &prison0;
prison_hold(np->netc_anon->cr_prison);
np->netc_numsecflavors = argp->ex_numsecflavors;
bcopy(argp->ex_secflavors, np->netc_secflavors,
sizeof(np->netc_secflavors));
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_DEFEXPORTED;
MNT_IUNLOCK(mp);
return (0);
}
#if MSIZE <= 256
if (argp->ex_addrlen > MLEN) {
vfs_mount_error(mp, "ex_addrlen %d is greater than %d",
argp->ex_addrlen, MLEN);
return (EINVAL);
}
#endif
i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen;
np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK | M_ZERO);
saddr = (struct sockaddr *) (np + 1);
if ((error = copyin(argp->ex_addr, saddr, argp->ex_addrlen)))
goto out;
if (saddr->sa_family == AF_UNSPEC || saddr->sa_family > AF_MAX) {
error = EINVAL;
vfs_mount_error(mp, "Invalid saddr->sa_family: %d");
goto out;
}
if (saddr->sa_len > argp->ex_addrlen)
saddr->sa_len = argp->ex_addrlen;
if (argp->ex_masklen) {
smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen);
error = copyin(argp->ex_mask, smask, argp->ex_masklen);
if (error)
goto out;
if (smask->sa_len > argp->ex_masklen)
smask->sa_len = argp->ex_masklen;
}
rnh = NULL;
switch (saddr->sa_family) {
#ifdef INET
case AF_INET:
if ((rnh = nep->ne4) == NULL) {
off = offsetof(struct sockaddr_in, sin_addr) << 3;
rnh = vfs_create_addrlist_af(&nep->ne4, off);
}
break;
#endif
#ifdef INET6
case AF_INET6:
if ((rnh = nep->ne6) == NULL) {
off = offsetof(struct sockaddr_in6, sin6_addr) << 3;
rnh = vfs_create_addrlist_af(&nep->ne6, off);
}
break;
#endif
}
if (rnh == NULL) {
error = ENOBUFS;
vfs_mount_error(mp, "%s %s %d",
"Unable to initialize radix node head ",
"for address family", saddr->sa_family);
goto out;
}
RADIX_NODE_HEAD_LOCK(rnh);
rn = (*rnh->rnh_addaddr)(saddr, smask, &rnh->rh, np->netc_rnodes);
RADIX_NODE_HEAD_UNLOCK(rnh);
if (rn == NULL || np != (struct netcred *)rn) { /* already exists */
error = EPERM;
vfs_mount_error(mp,
"netcred already exists for given addr/mask");
goto out;
}
np->netc_exflags = argp->ex_flags;
np->netc_anon = crget();
np->netc_anon->cr_uid = argp->ex_anon.cr_uid;
crsetgroups(np->netc_anon, argp->ex_anon.cr_ngroups,
argp->ex_anon.cr_groups);
np->netc_anon->cr_prison = &prison0;
prison_hold(np->netc_anon->cr_prison);
np->netc_numsecflavors = argp->ex_numsecflavors;
bcopy(argp->ex_secflavors, np->netc_secflavors,
sizeof(np->netc_secflavors));
return (0);
out:
free(np, M_NETADDR);
return (error);
}
/* Helper for vfs_free_addrlist. */
/* ARGSUSED */
static int
vfs_free_netcred(struct radix_node *rn, void *w)
{
struct radix_node_head *rnh = (struct radix_node_head *) w;
struct ucred *cred;
(*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, &rnh->rh);
cred = ((struct netcred *)rn)->netc_anon;
if (cred != NULL)
crfree(cred);
free(rn, M_NETADDR);
return (0);
}
#if defined(INET) || defined(INET6)
static struct radix_node_head *
vfs_create_addrlist_af(struct radix_node_head **prnh, int off)
{
if (rn_inithead((void **)prnh, off) == 0)
return (NULL);
RADIX_NODE_HEAD_LOCK_INIT(*prnh);
return (*prnh);
}
#endif
static void
vfs_free_addrlist_af(struct radix_node_head **prnh)
{
struct radix_node_head *rnh;
rnh = *prnh;
RADIX_NODE_HEAD_LOCK(rnh);
(*rnh->rnh_walktree)(&rnh->rh, vfs_free_netcred, rnh);
RADIX_NODE_HEAD_UNLOCK(rnh);
RADIX_NODE_HEAD_DESTROY(rnh);
rn_detachhead((void **)prnh);
prnh = NULL;
}
/*
* Free the net address hash lists that are hanging off the mount points.
*/
static void
vfs_free_addrlist(struct netexport *nep)
{
struct ucred *cred;
if (nep->ne4 != NULL)
vfs_free_addrlist_af(&nep->ne4);
if (nep->ne6 != NULL)
vfs_free_addrlist_af(&nep->ne6);
cred = nep->ne_defexported.netc_anon;
if (cred != NULL)
crfree(cred);
}
/*
* High level function to manipulate export options on a mount point
* and the passed in netexport.
* Struct export_args *argp is the variable used to twiddle options,
* the structure is described in sys/mount.h
*/
int
vfs_export(struct mount *mp, struct export_args *argp)
{
struct netexport *nep;
int error;
if (argp->ex_numsecflavors < 0
|| argp->ex_numsecflavors >= MAXSECFLAVORS)
return (EINVAL);
error = 0;
lockmgr(&mp->mnt_explock, LK_EXCLUSIVE, NULL);
nep = mp->mnt_export;
if (argp->ex_flags & MNT_DELEXPORT) {
if (nep == NULL) {
error = ENOENT;
goto out;
}
if (mp->mnt_flag & MNT_EXPUBLIC) {
vfs_setpublicfs(NULL, NULL, NULL);
MNT_ILOCK(mp);
mp->mnt_flag &= ~MNT_EXPUBLIC;
MNT_IUNLOCK(mp);
}
vfs_free_addrlist(nep);
mp->mnt_export = NULL;
free(nep, M_MOUNT);
nep = NULL;
MNT_ILOCK(mp);
mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED);
MNT_IUNLOCK(mp);
}
if (argp->ex_flags & MNT_EXPORTED) {
if (nep == NULL) {
nep = malloc(sizeof(struct netexport), M_MOUNT, M_WAITOK | M_ZERO);
mp->mnt_export = nep;
}
if (argp->ex_flags & MNT_EXPUBLIC) {
if ((error = vfs_setpublicfs(mp, nep, argp)) != 0)
goto out;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_EXPUBLIC;
MNT_IUNLOCK(mp);
}
if ((error = vfs_hang_addrlist(mp, nep, argp)))
goto out;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_EXPORTED;
MNT_IUNLOCK(mp);
}
out:
lockmgr(&mp->mnt_explock, LK_RELEASE, NULL);
/*
* Once we have executed the vfs_export() command, we do
* not want to keep the "export" option around in the
* options list, since that will cause subsequent MNT_UPDATE
* calls to fail. The export information is saved in
* mp->mnt_export, so we can safely delete the "export" mount option
* here.
*/
vfs_deleteopt(mp->mnt_optnew, "export");
vfs_deleteopt(mp->mnt_opt, "export");
return (error);
}
/*
* Set the publicly exported filesystem (WebNFS). Currently, only
* one public filesystem is possible in the spec (RFC 2054 and 2055)
*/
int
vfs_setpublicfs(struct mount *mp, struct netexport *nep,
struct export_args *argp)
{
int error;
struct vnode *rvp;
char *cp;
/*
* mp == NULL -> invalidate the current info, the FS is
* no longer exported. May be called from either vfs_export
* or unmount, so check if it hasn't already been done.
*/
if (mp == NULL) {
if (nfs_pub.np_valid) {
nfs_pub.np_valid = 0;
if (nfs_pub.np_index != NULL) {
free(nfs_pub.np_index, M_TEMP);
nfs_pub.np_index = NULL;
}
}
return (0);
}
/*
* Only one allowed at a time.
*/
if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount)
return (EBUSY);
/*
* Get real filehandle for root of exported FS.
*/
bzero(&nfs_pub.np_handle, sizeof(nfs_pub.np_handle));
nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid;
if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rvp)))
return (error);
if ((error = VOP_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid)))
return (error);
vput(rvp);
/*
* If an indexfile was specified, pull it in.
*/
if (argp->ex_indexfile != NULL) {
if (nfs_pub.np_index != NULL)
nfs_pub.np_index = malloc(MAXNAMLEN + 1, M_TEMP,
M_WAITOK);
error = copyinstr(argp->ex_indexfile, nfs_pub.np_index,
MAXNAMLEN, (size_t *)0);
if (!error) {
/*
* Check for illegal filenames.
*/
for (cp = nfs_pub.np_index; *cp; cp++) {
if (*cp == '/') {
error = EINVAL;
break;
}
}
}
if (error) {
free(nfs_pub.np_index, M_TEMP);
nfs_pub.np_index = NULL;
return (error);
}
}
nfs_pub.np_mount = mp;
nfs_pub.np_valid = 1;
return (0);
}
/*
* Used by the filesystems to determine if a given network address
* (passed in 'nam') is present in their exports list, returns a pointer
* to struct netcred so that the filesystem can examine it for
* access rights (read/write/etc).
*/
static struct netcred *
vfs_export_lookup(struct mount *mp, struct sockaddr *nam)
{
struct netexport *nep;
struct netcred *np = NULL;
struct radix_node_head *rnh;
struct sockaddr *saddr;
nep = mp->mnt_export;
if (nep == NULL)
return (NULL);
if ((mp->mnt_flag & MNT_EXPORTED) == 0)
return (NULL);
/*
* Lookup in the export list
*/
if (nam != NULL) {
saddr = nam;
rnh = NULL;
switch (saddr->sa_family) {
case AF_INET:
rnh = nep->ne4;
break;
case AF_INET6:
rnh = nep->ne6;
break;
}
if (rnh != NULL) {
RADIX_NODE_HEAD_RLOCK(rnh);
np = (struct netcred *) (*rnh->rnh_matchaddr)(saddr, &rnh->rh);
RADIX_NODE_HEAD_RUNLOCK(rnh);
if (np != NULL && (np->netc_rnodes->rn_flags & RNF_ROOT) != 0)
return (NULL);
}
}
/*
* If no address match, use the default if it exists.
*/
if (np == NULL && (mp->mnt_flag & MNT_DEFEXPORTED) != 0)
return (&nep->ne_defexported);
return (np);
}
/*
* XXX: This comment comes from the deprecated ufs_check_export()
* XXX: and may not entirely apply, but lacking something better:
* This is the generic part of fhtovp called after the underlying
* filesystem has validated the file handle.
*
* Verify that a host should have access to a filesystem.
*/
int
vfs_stdcheckexp(struct mount *mp, struct sockaddr *nam, int *extflagsp,
struct ucred **credanonp, int *numsecflavors, int **secflavors)
{
struct netcred *np;
lockmgr(&mp->mnt_explock, LK_SHARED, NULL);
np = vfs_export_lookup(mp, nam);
if (np == NULL) {
lockmgr(&mp->mnt_explock, LK_RELEASE, NULL);
*credanonp = NULL;
return (EACCES);
}
*extflagsp = np->netc_exflags;
if ((*credanonp = np->netc_anon) != NULL)
crhold(*credanonp);
if (numsecflavors)
*numsecflavors = np->netc_numsecflavors;
if (secflavors)
*secflavors = np->netc_secflavors;
lockmgr(&mp->mnt_explock, LK_RELEASE, NULL);
return (0);
}
