hardenedbsd/HardenedBSD
1
0
Fork 0
mirror of https://git.hardenedbsd.org/hardenedbsd/HardenedBSD.git synced 2024-12-30 15:38:06 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity
912e4916d0
HardenedBSD/sys/nfsserver/nfs_srvcache.c
Doug Rabson a9148abd9d Implement support for RPCSEC_GSS authentication to both the NFS client 
and server. This replaces the RPC implementation of the NFS client and
server with the newer RPC implementation originally developed
(actually ported from the userland sunrpc code) to support the NFS
Lock Manager.  I have tested this code extensively and I believe it is
stable and that performance is at least equal to the legacy RPC
implementation.

The NFS code currently contains support for both the new RPC
implementation and the older legacy implementation inherited from the
original NFS codebase. The default is to use the new implementation -
add the NFS_LEGACYRPC option to fall back to the old code. When I
merge this support back to RELENG_7, I will probably change this so
that users have to 'opt in' to get the new code.

To use RPCSEC_GSS on either client or server, you must build a kernel
which includes the KGSSAPI option and the crypto device. On the
userland side, you must build at least a new libc, mountd, mount_nfs
and gssd. You must install new versions of /etc/rc.d/gssd and
/etc/rc.d/nfsd and add 'gssd_enable=YES' to /etc/rc.conf.

As long as gssd is running, you should be able to mount an NFS
filesystem from a server that requires RPCSEC_GSS authentication. The
mount itself can happen without any kerberos credentials but all
access to the filesystem will be denied unless the accessing user has
a valid ticket file in the standard place (/tmp/krb5cc_<uid>). There
is currently no support for situations where the ticket file is in a
different place, such as when the user logged in via SSH and has
delegated credentials from that login. This restriction is also
present in Solaris and Linux. In theory, we could improve this in
future, possibly using Brooks Davis' implementation of variant
symlinks.

Supporting RPCSEC_GSS on a server is nearly as simple. You must create
service creds for the server in the form 'nfs/<fqdn>@<REALM>' and
install them in /etc/krb5.keytab. The standard heimdal utility ktutil
makes this fairly easy. After the service creds have been created, you
can add a '-sec=krb5' option to /etc/exports and restart both mountd
and nfsd.

The only other difference an administrator should notice is that nfsd
doesn't fork to create service threads any more. In normal operation,
there will be two nfsd processes, one in userland waiting for TCP
connections and one in the kernel handling requests. The latter
process will create as many kthreads as required - these should be
visible via 'top -H'. The code has some support for varying the number
of service threads according to load but initially at least, nfsd uses
a fixed number of threads according to the value supplied to its '-n'
option.

Sponsored by:	Isilon Systems
MFC after:	1 month
2008-11-03 10:38:00 +00:00

392 lines
10 KiB
C
Raw Blame History

/*-
* 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.
* 4. 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_srvcache.c 8.3 (Berkeley) 3/30/95
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Reference: Chet Juszczak, "Improving the Performance and Correctness
* of an NFS Server", in Proc. Winter 1989 USENIX Conference,
* pages 53-63. San Diego, February 1989.
*/
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/socketvar.h> /* for sodupsockaddr */
#include <sys/eventhandler.h>
#include <netinet/in.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfsserver/nfs.h>
#include <nfsserver/nfsrvcache.h>
#ifdef NFS_LEGACYRPC
static long numnfsrvcache;
static long desirednfsrvcache;
#define NFSRCHASH(xid) \
(&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash])
static LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl;
static TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead;
static u_long nfsrvhash;
static eventhandler_tag nfsrv_nmbclusters_tag;
#define TRUE 1
#define FALSE 0
#define NETFAMILY(rp) \
(((rp)->rc_flag & RC_NAM) ? (rp)->rc_nam->sa_family : AF_INET)
/*
* Static array that defines which nfs rpc's are nonidempotent
*/
static const int nonidempotent[NFS_NPROCS] = {
FALSE,
FALSE,
TRUE,
FALSE,
FALSE,
FALSE,
FALSE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
};
/* True iff the rpc reply is an nfs status ONLY! */
static const int nfsv2_repstat[NFS_NPROCS] = {
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
TRUE,
TRUE,
TRUE,
TRUE,
FALSE,
TRUE,
FALSE,
FALSE,
};
/*
* Size the NFS server's duplicate request cache at 1/2 the nmbclsters, floating
* within a (64, 2048) range. This is to prevent all mbuf clusters being tied up
* in the NFS dupreq cache for small values of nmbclusters.
*/
static void
nfsrvcache_size_change(void *tag)
{
desirednfsrvcache = nmbclusters /2;
if (desirednfsrvcache > NFSRVCACHE_MAX_SIZE)
desirednfsrvcache = NFSRVCACHE_MAX_SIZE;
if (desirednfsrvcache < NFSRVCACHE_MIN_SIZE)
desirednfsrvcache = NFSRVCACHE_MIN_SIZE;
}
/*
* Initialize the server request cache list
*/
void
nfsrv_initcache(void)
{
nfsrvcache_size_change(NULL);
nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash);
TAILQ_INIT(&nfsrvlruhead);
nfsrv_nmbclusters_tag = EVENTHANDLER_REGISTER(nmbclusters_change,
nfsrvcache_size_change, NULL, EVENTHANDLER_PRI_FIRST);
}
/*
* Teardown the server request cache list
*/
void
nfsrv_destroycache(void)
{
KASSERT(TAILQ_EMPTY(&nfsrvlruhead), ("%s: pending requests", __func__));
EVENTHANDLER_DEREGISTER(nmbclusters_change, nfsrv_nmbclusters_tag);
hashdestroy(nfsrvhashtbl, M_NFSD, nfsrvhash);
}
/*
* Look for the request in the cache
* If found then
* return action and optionally reply
* else
* insert it in the cache
*
* The rules are as follows:
* - if in progress, return DROP request
* - if completed within DELAY of the current time, return DROP it
* - if completed a longer time ago return REPLY if the reply was cached or
* return DOIT
* Update/add new request at end of lru list
*/
int
nfsrv_getcache(struct nfsrv_descript *nd, struct mbuf **repp)
{
struct nfsrvcache *rp;
struct mbuf *mb;
struct sockaddr_in *saddr;
caddr_t bpos;
int ret;
NFSD_LOCK_ASSERT();
/*
* Don't cache recent requests for reliable transport protocols.
* (Maybe we should for the case of a reconnect, but..)
*/
if (!nd->nd_nam2)
return (RC_DOIT);
loop:
LIST_FOREACH(rp, NFSRCHASH(nd->nd_retxid), rc_hash) {
if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc &&
netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) {
NFS_DPF(RC, ("H%03x", rp->rc_xid & 0xfff));
if ((rp->rc_flag & RC_LOCKED) != 0) {
rp->rc_flag |= RC_WANTED;
(void) msleep(rp, &nfsd_mtx, PZERO-1,
"nfsrc", 0);
goto loop;
}
rp->rc_flag |= RC_LOCKED;
/* If not at end of LRU chain, move it there */
if (TAILQ_NEXT(rp, rc_lru)) {
TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);
}
if (rp->rc_state == RC_UNUSED)
panic("nfsrv cache");
if (rp->rc_state == RC_INPROG) {
nfsrvstats.srvcache_inproghits++;
ret = RC_DROPIT;
} else if (rp->rc_flag & RC_REPSTATUS) {
nfsrvstats.srvcache_nonidemdonehits++;
NFSD_UNLOCK();
*repp = nfs_rephead(0, nd, rp->rc_status,
&mb, &bpos);
ret = RC_REPLY;
NFSD_LOCK();
} else if (rp->rc_flag & RC_REPMBUF) {
nfsrvstats.srvcache_nonidemdonehits++;
NFSD_UNLOCK();
*repp = m_copym(rp->rc_reply, 0, M_COPYALL,
M_WAIT);
NFSD_LOCK();
ret = RC_REPLY;
} else {
nfsrvstats.srvcache_idemdonehits++;
rp->rc_state = RC_INPROG;
ret = RC_DOIT;
}
rp->rc_flag &= ~RC_LOCKED;
if (rp->rc_flag & RC_WANTED) {
rp->rc_flag &= ~RC_WANTED;
wakeup(rp);
}
return (ret);
}
}
nfsrvstats.srvcache_misses++;
NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff));
if (numnfsrvcache < desirednfsrvcache) {
NFSD_UNLOCK();
rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp,
M_NFSD, M_WAITOK | M_ZERO);
NFSD_LOCK();
numnfsrvcache++;
rp->rc_flag = RC_LOCKED;
} else {
rp = TAILQ_FIRST(&nfsrvlruhead);
while ((rp->rc_flag & RC_LOCKED) != 0) {
rp->rc_flag |= RC_WANTED;
(void) msleep(rp, &nfsd_mtx, PZERO-1, "nfsrc", 0);
rp = TAILQ_FIRST(&nfsrvlruhead);
}
rp->rc_flag |= RC_LOCKED;
LIST_REMOVE(rp, rc_hash);
TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
if (rp->rc_flag & RC_REPMBUF)
m_freem(rp->rc_reply);
if (rp->rc_flag & RC_NAM)
free(rp->rc_nam, M_SONAME);
rp->rc_flag &= (RC_LOCKED | RC_WANTED);
}
TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);
rp->rc_state = RC_INPROG;
rp->rc_xid = nd->nd_retxid;
saddr = (struct sockaddr_in *)nd->nd_nam;
switch (saddr->sin_family) {
case AF_INET:
rp->rc_flag |= RC_INETADDR;
rp->rc_inetaddr = saddr->sin_addr.s_addr;
break;
/* case AF_INET6: */
/* case AF_ISO: */
default:
/*
* XXXRW: Seems like we should only set RC_NAM if we
* actually manage to set rc_nam to something non-NULL.
*/
rp->rc_flag |= RC_NAM;
rp->rc_nam = sodupsockaddr(nd->nd_nam, M_NOWAIT);
break;
};
rp->rc_proc = nd->nd_procnum;
LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash);
rp->rc_flag &= ~RC_LOCKED;
if (rp->rc_flag & RC_WANTED) {
rp->rc_flag &= ~RC_WANTED;
wakeup(rp);
}
return (RC_DOIT);
}
/*
* Update a request cache entry after the rpc has been done
*/
void
nfsrv_updatecache(struct nfsrv_descript *nd, int repvalid, struct mbuf *repmbuf)
{
struct nfsrvcache *rp;
NFSD_LOCK_ASSERT();
if (!nd->nd_nam2)
return;
loop:
LIST_FOREACH(rp, NFSRCHASH(nd->nd_retxid), rc_hash) {
if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc &&
netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) {
NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff));
if ((rp->rc_flag & RC_LOCKED) != 0) {
rp->rc_flag |= RC_WANTED;
(void) msleep(rp, &nfsd_mtx, PZERO-1,
"nfsrc", 0);
goto loop;
}
rp->rc_flag |= RC_LOCKED;
if (rp->rc_state == RC_DONE) {
/*
* This can occur if the cache is too small.
* Retransmits of the same request aren't
* dropped so we may see the operation
* complete more then once.
*/
if (rp->rc_flag & RC_REPMBUF) {
m_freem(rp->rc_reply);
rp->rc_flag &= ~RC_REPMBUF;
}
}
rp->rc_state = RC_DONE;
/*
* If we have a valid reply update status and save
* the reply for non-idempotent rpc's.
*/
if (repvalid && nonidempotent[nd->nd_procnum]) {
if ((nd->nd_flag & ND_NFSV3) == 0 &&
nfsv2_repstat[
nfsrvv2_procid[nd->nd_procnum]]) {
rp->rc_status = nd->nd_repstat;
rp->rc_flag |= RC_REPSTATUS;
} else {
NFSD_UNLOCK();
rp->rc_reply = m_copym(repmbuf,
0, M_COPYALL, M_WAIT);
NFSD_LOCK();
rp->rc_flag |= RC_REPMBUF;
}
}
rp->rc_flag &= ~RC_LOCKED;
if (rp->rc_flag & RC_WANTED) {
rp->rc_flag &= ~RC_WANTED;
wakeup(rp);
}
return;
}
}
NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff));
}
/*
* Clean out the cache. Called when the last nfsd terminates.
*/
void
nfsrv_cleancache(void)
{
struct nfsrvcache *rp, *nextrp;
NFSD_LOCK_ASSERT();
TAILQ_FOREACH_SAFE(rp, &nfsrvlruhead, rc_lru, nextrp) {
LIST_REMOVE(rp, rc_hash);
TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
if (rp->rc_flag & RC_REPMBUF)
m_freem(rp->rc_reply);
if (rp->rc_flag & RC_NAM)
free(rp->rc_nam, M_SONAME);
free(rp, M_NFSD);
}
numnfsrvcache = 0;
}
#endif /* NFS_LEGACYRPC */
Reference in New Issue View Git Blame Copy Permalink