NetBSD/sys/nfs/nfs_srvsubs.c

420 lines
11 KiB
C

/* $NetBSD: nfs_srvsubs.c,v 1.6 2010/06/24 13:03:17 hannken Exp $ */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rick Macklem at The University of Guelph.
*
* 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.
*
* @(#)nfs_subs.c 8.8 (Berkeley) 5/22/95
*/
/*
* Copyright 2000 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Frank van der Linden for Wasabi Systems, 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: nfs_srvsubs.c,v 1.6 2010/06/24 13:03:17 hannken Exp $");
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/kmem.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/filedesc.h>
#include <sys/time.h>
#include <sys/dirent.h>
#include <sys/once.h>
#include <sys/kauth.h>
#include <sys/atomic.h>
#include <uvm/uvm_extern.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfsnode.h>
#include <nfs/nfs.h>
#include <nfs/xdr_subs.h>
#include <nfs/nfsm_subs.h>
#include <nfs/nfsmount.h>
#include <nfs/nfsrtt.h>
#include <nfs/nfs_var.h>
#include <miscfs/specfs/specdev.h>
#include <netinet/in.h>
/*
* Set up nameidata for a lookup() call and do it.
*
* If pubflag is set, this call is done for a lookup operation on the
* public filehandle. In that case we allow crossing mountpoints and
* absolute pathnames. However, the caller is expected to check that
* the lookup result is within the public fs, and deny access if
* it is not.
*/
int
nfs_namei(struct nameidata *ndp, nfsrvfh_t *nsfh, uint32_t len, struct nfssvc_sock *slp, struct mbuf *nam, struct mbuf **mdp, char **dposp, struct vnode **retdirp, struct lwp *l, int kerbflag, int pubflag)
{
int i, rem;
struct mbuf *md;
char *fromcp, *tocp, *cp;
struct vnode *dp;
int error, rdonly;
int neverfollow;
struct componentname *cnp = &ndp->ni_cnd;
*retdirp = NULL;
if ((len + 1) > MAXPATHLEN)
return (ENAMETOOLONG);
if (len == 0)
return (EACCES);
cnp->cn_pnbuf = PNBUF_GET();
/*
* Copy the name from the mbuf list to ndp->ni_pnbuf
* and set the various ndp fields appropriately.
*/
fromcp = *dposp;
tocp = cnp->cn_pnbuf;
md = *mdp;
rem = mtod(md, char *) + md->m_len - fromcp;
for (i = 0; i < len; i++) {
while (rem == 0) {
md = md->m_next;
if (md == NULL) {
error = EBADRPC;
goto out;
}
fromcp = mtod(md, void *);
rem = md->m_len;
}
if (*fromcp == '\0' || (!pubflag && *fromcp == '/')) {
error = EACCES;
goto out;
}
*tocp++ = *fromcp++;
rem--;
}
*tocp = '\0';
*mdp = md;
*dposp = fromcp;
len = nfsm_rndup(len)-len;
if (len > 0) {
if (rem >= len)
*dposp += len;
else if ((error = nfs_adv(mdp, dposp, len, rem)) != 0)
goto out;
}
/*
* Extract and set starting directory.
*/
error = nfsrv_fhtovp(nsfh, false, &dp, ndp->ni_cnd.cn_cred, slp,
nam, &rdonly, kerbflag, pubflag);
if (error)
goto out;
if (dp->v_type != VDIR) {
vrele(dp);
error = ENOTDIR;
goto out;
}
if (rdonly)
cnp->cn_flags |= RDONLY;
*retdirp = dp;
if (pubflag) {
/*
* Oh joy. For WebNFS, handle those pesky '%' escapes,
* and the 'native path' indicator.
*/
cp = PNBUF_GET();
fromcp = cnp->cn_pnbuf;
tocp = cp;
if ((unsigned char)*fromcp >= WEBNFS_SPECCHAR_START) {
switch ((unsigned char)*fromcp) {
case WEBNFS_NATIVE_CHAR:
/*
* 'Native' path for us is the same
* as a path according to the NFS spec,
* just skip the escape char.
*/
fromcp++;
break;
/*
* More may be added in the future, range 0x80-0xff
*/
default:
error = EIO;
vrele(dp);
PNBUF_PUT(cp);
goto out;
}
}
/*
* Translate the '%' escapes, URL-style.
*/
while (*fromcp != '\0') {
if (*fromcp == WEBNFS_ESC_CHAR) {
if (fromcp[1] != '\0' && fromcp[2] != '\0') {
fromcp++;
*tocp++ = HEXSTRTOI(fromcp);
fromcp += 2;
continue;
} else {
error = ENOENT;
vrele(dp);
PNBUF_PUT(cp);
goto out;
}
} else
*tocp++ = *fromcp++;
}
*tocp = '\0';
PNBUF_PUT(cnp->cn_pnbuf);
cnp->cn_pnbuf = cp;
}
ndp->ni_pathlen = (tocp - cnp->cn_pnbuf) + 1;
ndp->ni_segflg = UIO_SYSSPACE;
ndp->ni_rootdir = rootvnode;
ndp->ni_erootdir = NULL;
if (pubflag) {
ndp->ni_loopcnt = 0;
if (cnp->cn_pnbuf[0] == '/')
dp = rootvnode;
} else {
cnp->cn_flags |= NOCROSSMOUNT;
}
neverfollow = !pubflag;
/*
* And call lookup() to do the real work
*/
error = lookup_for_nfsd(ndp, dp, neverfollow);
if (error) {
return (error);
}
return 0;
out:
PNBUF_PUT(cnp->cn_pnbuf);
return (error);
}
/*
* nfsrv_fhtovp() - convert a fh to a vnode ptr (optionally locked)
* - look up fsid in mount list (if not found ret error)
* - get vp and export rights by calling VFS_FHTOVP()
* - if cred->cr_uid == 0 or MNT_EXPORTANON set it to credanon
* - if not lockflag unlock it with VOP_UNLOCK()
*/
int
nfsrv_fhtovp(nfsrvfh_t *nsfh, int lockflag, struct vnode **vpp,
kauth_cred_t cred, struct nfssvc_sock *slp, struct mbuf *nam, int *rdonlyp,
int kerbflag, int pubflag)
{
struct mount *mp;
kauth_cred_t credanon;
int error, exflags;
struct sockaddr_in *saddr;
fhandle_t *fhp;
fhp = NFSRVFH_FHANDLE(nsfh);
*vpp = (struct vnode *)0;
if (nfs_ispublicfh(nsfh)) {
if (!pubflag || !nfs_pub.np_valid)
return (ESTALE);
fhp = nfs_pub.np_handle;
}
error = netexport_check(&fhp->fh_fsid, nam, &mp, &exflags, &credanon);
if (error) {
return error;
}
error = VFS_FHTOVP(mp, &fhp->fh_fid, vpp);
if (error)
return (error);
if (!(exflags & (MNT_EXNORESPORT|MNT_EXPUBLIC))) {
saddr = mtod(nam, struct sockaddr_in *);
if ((saddr->sin_family == AF_INET) &&
ntohs(saddr->sin_port) >= IPPORT_RESERVED) {
vput(*vpp);
return (NFSERR_AUTHERR | AUTH_TOOWEAK);
}
if ((saddr->sin_family == AF_INET6) &&
ntohs(saddr->sin_port) >= IPV6PORT_RESERVED) {
vput(*vpp);
return (NFSERR_AUTHERR | AUTH_TOOWEAK);
}
}
/*
* Check/setup credentials.
*/
if (exflags & MNT_EXKERB) {
if (!kerbflag) {
vput(*vpp);
return (NFSERR_AUTHERR | AUTH_TOOWEAK);
}
} else if (kerbflag) {
vput(*vpp);
return (NFSERR_AUTHERR | AUTH_TOOWEAK);
} else if (kauth_cred_geteuid(cred) == 0 || /* NFS maproot, see below */
(exflags & MNT_EXPORTANON)) {
/*
* This is used by the NFS maproot option. While we can change
* the secmodel on our own host, we can't change it on the
* clients. As means of least surprise, we're doing the
* traditional thing here.
* Should look into adding a "mapprivileged" or similar where
* the users can be explicitly specified...
* [elad, yamt 2008-03-05]
*/
kauth_cred_clone(credanon, cred);
}
if (exflags & MNT_EXRDONLY)
*rdonlyp = 1;
else
*rdonlyp = 0;
if (!lockflag)
VOP_UNLOCK(*vpp);
return (0);
}
/*
* WebNFS: check if a filehandle is a public filehandle. For v3, this
* means a length of 0, for v2 it means all zeroes.
*/
int
nfs_ispublicfh(const nfsrvfh_t *nsfh)
{
const char *cp = (const void *)(NFSRVFH_DATA(nsfh));
int i;
if (NFSRVFH_SIZE(nsfh) == 0) {
return true;
}
if (NFSRVFH_SIZE(nsfh) != NFSX_V2FH) {
return false;
}
for (i = 0; i < NFSX_V2FH; i++)
if (*cp++ != 0)
return false;
return true;
}
int
nfsrv_composefh(struct vnode *vp, nfsrvfh_t *nsfh, bool v3)
{
int error;
size_t fhsize;
fhsize = NFSD_MAXFHSIZE;
error = vfs_composefh(vp, (void *)NFSRVFH_DATA(nsfh), &fhsize);
if (NFSX_FHTOOBIG_P(fhsize, v3)) {
error = EOPNOTSUPP;
}
if (error != 0) {
return error;
}
if (!v3 && fhsize < NFSX_V2FH) {
memset((char *)NFSRVFH_DATA(nsfh) + fhsize, 0,
NFSX_V2FH - fhsize);
fhsize = NFSX_V2FH;
}
if ((fhsize % NFSX_UNSIGNED) != 0) {
return EOPNOTSUPP;
}
nsfh->nsfh_size = fhsize;
return 0;
}
int
nfsrv_comparefh(const nfsrvfh_t *fh1, const nfsrvfh_t *fh2)
{
if (NFSRVFH_SIZE(fh1) != NFSRVFH_SIZE(fh2)) {
return NFSRVFH_SIZE(fh2) - NFSRVFH_SIZE(fh1);
}
return memcmp(NFSRVFH_DATA(fh1), NFSRVFH_DATA(fh2), NFSRVFH_SIZE(fh1));
}
void
nfsrv_copyfh(nfsrvfh_t *fh1, const nfsrvfh_t *fh2)
{
size_t size;
fh1->nsfh_size = size = NFSRVFH_SIZE(fh2);
memcpy(NFSRVFH_DATA(fh1), NFSRVFH_DATA(fh2), size);
}