freebsd-skq/sys/rpc/rpc_prot.c
dfr 2fb03513fc 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

374 lines
9.0 KiB
C

/* $NetBSD: rpc_prot.c,v 1.16 2000/06/02 23:11:13 fvdl Exp $ */
/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char *sccsid2 = "@(#)rpc_prot.c 1.36 87/08/11 Copyr 1984 Sun Micro";
static char *sccsid = "@(#)rpc_prot.c 2.3 88/08/07 4.0 RPCSRC";
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* rpc_prot.c
*
* Copyright (C) 1984, Sun Microsystems, Inc.
*
* This set of routines implements the rpc message definition,
* its serializer and some common rpc utility routines.
* The routines are meant for various implementations of rpc -
* they are NOT for the rpc client or rpc service implementations!
* Because authentication stuff is easy and is part of rpc, the opaque
* routines are also in this program.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <rpc/auth.h>
#include <rpc/clnt.h>
#include <rpc/rpc_msg.h>
MALLOC_DEFINE(M_RPC, "rpc", "Remote Procedure Call");
#define assert(exp) KASSERT(exp, ("bad arguments"))
static enum clnt_stat accepted(enum accept_stat, struct rpc_err *);
static enum clnt_stat rejected(enum reject_stat, struct rpc_err *);
/* * * * * * * * * * * * * * XDR Authentication * * * * * * * * * * * */
struct opaque_auth _null_auth;
/*
* XDR an opaque authentication struct
* (see auth.h)
*/
bool_t
xdr_opaque_auth(XDR *xdrs, struct opaque_auth *ap)
{
assert(xdrs != NULL);
assert(ap != NULL);
if (xdr_enum(xdrs, &(ap->oa_flavor)))
return (xdr_bytes(xdrs, &ap->oa_base,
&ap->oa_length, MAX_AUTH_BYTES));
return (FALSE);
}
/* * * * * * * * * * * * * * XDR RPC MESSAGE * * * * * * * * * * * * * * * */
/*
* XDR the MSG_ACCEPTED part of a reply message union
*/
bool_t
xdr_accepted_reply(XDR *xdrs, struct accepted_reply *ar)
{
enum accept_stat *par_stat;
assert(xdrs != NULL);
assert(ar != NULL);
par_stat = &ar->ar_stat;
/* personalized union, rather than calling xdr_union */
if (! xdr_opaque_auth(xdrs, &(ar->ar_verf)))
return (FALSE);
if (! xdr_enum(xdrs, (enum_t *) par_stat))
return (FALSE);
switch (ar->ar_stat) {
case SUCCESS:
if (ar->ar_results.proc != (xdrproc_t) xdr_void)
return ((*(ar->ar_results.proc))(xdrs,
ar->ar_results.where));
else
return (TRUE);
case PROG_MISMATCH:
if (! xdr_uint32_t(xdrs, &(ar->ar_vers.low)))
return (FALSE);
return (xdr_uint32_t(xdrs, &(ar->ar_vers.high)));
case GARBAGE_ARGS:
case SYSTEM_ERR:
case PROC_UNAVAIL:
case PROG_UNAVAIL:
break;
}
return (TRUE); /* TRUE => open ended set of problems */
}
/*
* XDR the MSG_DENIED part of a reply message union
*/
bool_t
xdr_rejected_reply(XDR *xdrs, struct rejected_reply *rr)
{
enum reject_stat *prj_stat;
enum auth_stat *prj_why;
assert(xdrs != NULL);
assert(rr != NULL);
prj_stat = &rr->rj_stat;
/* personalized union, rather than calling xdr_union */
if (! xdr_enum(xdrs, (enum_t *) prj_stat))
return (FALSE);
switch (rr->rj_stat) {
case RPC_MISMATCH:
if (! xdr_uint32_t(xdrs, &(rr->rj_vers.low)))
return (FALSE);
return (xdr_uint32_t(xdrs, &(rr->rj_vers.high)));
case AUTH_ERROR:
prj_why = &rr->rj_why;
return (xdr_enum(xdrs, (enum_t *) prj_why));
}
/* NOTREACHED */
assert(0);
return (FALSE);
}
static const struct xdr_discrim reply_dscrm[3] = {
{ (int)MSG_ACCEPTED, (xdrproc_t)xdr_accepted_reply },
{ (int)MSG_DENIED, (xdrproc_t)xdr_rejected_reply },
{ __dontcare__, NULL_xdrproc_t } };
/*
* XDR a reply message
*/
bool_t
xdr_replymsg(XDR *xdrs, struct rpc_msg *rmsg)
{
int32_t *buf;
enum msg_type *prm_direction;
enum reply_stat *prp_stat;
assert(xdrs != NULL);
assert(rmsg != NULL);
if (xdrs->x_op == XDR_DECODE) {
buf = XDR_INLINE(xdrs, 3 * BYTES_PER_XDR_UNIT);
if (buf != NULL) {
rmsg->rm_xid = IXDR_GET_UINT32(buf);
rmsg->rm_direction = IXDR_GET_ENUM(buf, enum msg_type);
if (rmsg->rm_direction != REPLY) {
return (FALSE);
}
rmsg->rm_reply.rp_stat =
IXDR_GET_ENUM(buf, enum reply_stat);
if (rmsg->rm_reply.rp_stat == MSG_ACCEPTED)
return (xdr_accepted_reply(xdrs,
&rmsg->acpted_rply));
else if (rmsg->rm_reply.rp_stat == MSG_DENIED)
return (xdr_rejected_reply(xdrs,
&rmsg->rjcted_rply));
else
return (FALSE);
}
}
prm_direction = &rmsg->rm_direction;
prp_stat = &rmsg->rm_reply.rp_stat;
if (
xdr_uint32_t(xdrs, &(rmsg->rm_xid)) &&
xdr_enum(xdrs, (enum_t *) prm_direction) &&
(rmsg->rm_direction == REPLY) )
return (xdr_union(xdrs, (enum_t *) prp_stat,
(caddr_t)(void *)&(rmsg->rm_reply.ru), reply_dscrm,
NULL_xdrproc_t));
return (FALSE);
}
/*
* Serializes the "static part" of a call message header.
* The fields include: rm_xid, rm_direction, rpcvers, prog, and vers.
* The rm_xid is not really static, but the user can easily munge on the fly.
*/
bool_t
xdr_callhdr(XDR *xdrs, struct rpc_msg *cmsg)
{
enum msg_type *prm_direction;
assert(xdrs != NULL);
assert(cmsg != NULL);
prm_direction = &cmsg->rm_direction;
cmsg->rm_direction = CALL;
cmsg->rm_call.cb_rpcvers = RPC_MSG_VERSION;
if (
(xdrs->x_op == XDR_ENCODE) &&
xdr_uint32_t(xdrs, &(cmsg->rm_xid)) &&
xdr_enum(xdrs, (enum_t *) prm_direction) &&
xdr_uint32_t(xdrs, &(cmsg->rm_call.cb_rpcvers)) &&
xdr_uint32_t(xdrs, &(cmsg->rm_call.cb_prog)) )
return (xdr_uint32_t(xdrs, &(cmsg->rm_call.cb_vers)));
return (FALSE);
}
/* ************************** Client utility routine ************* */
static enum clnt_stat
accepted(enum accept_stat acpt_stat, struct rpc_err *error)
{
assert(error != NULL);
switch (acpt_stat) {
case PROG_UNAVAIL:
error->re_status = RPC_PROGUNAVAIL;
return (RPC_PROGUNAVAIL);
case PROG_MISMATCH:
error->re_status = RPC_PROGVERSMISMATCH;
return (RPC_PROGVERSMISMATCH);
case PROC_UNAVAIL:
return (RPC_PROCUNAVAIL);
case GARBAGE_ARGS:
return (RPC_CANTDECODEARGS);
case SYSTEM_ERR:
return (RPC_SYSTEMERROR);
case SUCCESS:
return (RPC_SUCCESS);
}
/* NOTREACHED */
/* something's wrong, but we don't know what ... */
error->re_lb.s1 = (int32_t)MSG_ACCEPTED;
error->re_lb.s2 = (int32_t)acpt_stat;
return (RPC_FAILED);
}
static enum clnt_stat
rejected(enum reject_stat rjct_stat, struct rpc_err *error)
{
assert(error != NULL);
switch (rjct_stat) {
case RPC_MISMATCH:
return (RPC_VERSMISMATCH);
case AUTH_ERROR:
return (RPC_AUTHERROR);
}
/* something's wrong, but we don't know what ... */
/* NOTREACHED */
error->re_lb.s1 = (int32_t)MSG_DENIED;
error->re_lb.s2 = (int32_t)rjct_stat;
return (RPC_FAILED);
}
/*
* given a reply message, fills in the error
*/
enum clnt_stat
_seterr_reply(struct rpc_msg *msg, struct rpc_err *error)
{
enum clnt_stat stat;
assert(msg != NULL);
assert(error != NULL);
/* optimized for normal, SUCCESSful case */
switch (msg->rm_reply.rp_stat) {
case MSG_ACCEPTED:
if (msg->acpted_rply.ar_stat == SUCCESS) {
stat = RPC_SUCCESS;
return (stat);
}
stat = accepted(msg->acpted_rply.ar_stat, error);
break;
case MSG_DENIED:
stat = rejected(msg->rjcted_rply.rj_stat, error);
break;
default:
stat = RPC_FAILED;
error->re_lb.s1 = (int32_t)(msg->rm_reply.rp_stat);
break;
}
error->re_status = stat;
switch (stat) {
case RPC_VERSMISMATCH:
error->re_vers.low = msg->rjcted_rply.rj_vers.low;
error->re_vers.high = msg->rjcted_rply.rj_vers.high;
break;
case RPC_AUTHERROR:
error->re_why = msg->rjcted_rply.rj_why;
break;
case RPC_PROGVERSMISMATCH:
error->re_vers.low = msg->acpted_rply.ar_vers.low;
error->re_vers.high = msg->acpted_rply.ar_vers.high;
break;
case RPC_FAILED:
case RPC_SUCCESS:
case RPC_PROGNOTREGISTERED:
case RPC_PMAPFAILURE:
case RPC_UNKNOWNPROTO:
case RPC_UNKNOWNHOST:
case RPC_SYSTEMERROR:
case RPC_CANTDECODEARGS:
case RPC_PROCUNAVAIL:
case RPC_PROGUNAVAIL:
case RPC_TIMEDOUT:
case RPC_CANTRECV:
case RPC_CANTSEND:
case RPC_CANTDECODERES:
case RPC_CANTENCODEARGS:
default:
break;
}
return (stat);
}