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

1 files changed, 25 insertions, 20 deletions

diff --git a/sys/rpc/auth.h b/sys/rpc/auth.h
index b919559d68c2..6be08b625601 100644
--- a/sys/rpc/auth.h
+++ b/sys/rpc/auth.h
@@ -132,7 +132,7 @@ enum auth_stat {
 	 * failed locally
 	*/
 	AUTH_INVALIDRESP=6,		/* bogus response verifier */
-	AUTH_FAILED=7			/* some unknown reason */
+	AUTH_FAILED=7,			/* some unknown reason */
 #ifdef KERBEROS
 	/*
 	 * kerberos errors
@@ -142,8 +142,14 @@ enum auth_stat {
 	AUTH_TIMEEXPIRE = 9,		/* time of credential expired */
 	AUTH_TKT_FILE = 10,		/* something wrong with ticket file */
 	AUTH_DECODE = 11,			/* can't decode authenticator */
-	AUTH_NET_ADDR = 12		/* wrong net address in ticket */
+	AUTH_NET_ADDR = 12,		/* wrong net address in ticket */
 #endif /* KERBEROS */
+	/*
+	 * RPCSEC_GSS errors
+	 */
+	RPCSEC_GSS_CREDPROBLEM = 13,
+	RPCSEC_GSS_CTXPROBLEM = 14,
+	RPCSEC_GSS_NODISPATCH = 0x8000000
 };
 
 union des_block {
@@ -171,6 +177,7 @@ struct opaque_auth {
 /*
  * Auth handle, interface to client side authenticators.
  */
+struct rpc_err;
 typedef struct __auth {
 	struct	opaque_auth	ah_cred;
 	struct	opaque_auth	ah_verf;
@@ -178,10 +185,11 @@ typedef struct __auth {
 	struct auth_ops {
 		void	(*ah_nextverf) (struct __auth *);
 		/* nextverf & serialize */
-		int	(*ah_marshal) (struct __auth *, XDR *);
+		int	(*ah_marshal) (struct __auth *, uint32_t, XDR *,
+		    struct mbuf *);
 		/* validate verifier */
-		int	(*ah_validate) (struct __auth *,
-			    struct opaque_auth *);
+		int	(*ah_validate) (struct __auth *, uint32_t,
+		    struct opaque_auth *, struct mbuf **);
 		/* refresh credentials */
 		int	(*ah_refresh) (struct __auth *, void *);
 		/* destroy this structure */
@@ -201,29 +209,18 @@ typedef struct __auth {
  */
 #define AUTH_NEXTVERF(auth)		\
 		((*((auth)->ah_ops->ah_nextverf))(auth))
-#define auth_nextverf(auth)		\
-		((*((auth)->ah_ops->ah_nextverf))(auth))
 
-#define AUTH_MARSHALL(auth, xdrs)	\
-		((*((auth)->ah_ops->ah_marshal))(auth, xdrs))
-#define auth_marshall(auth, xdrs)	\
-		((*((auth)->ah_ops->ah_marshal))(auth, xdrs))
+#define AUTH_MARSHALL(auth, xid, xdrs, args)	\
+		((*((auth)->ah_ops->ah_marshal))(auth, xid, xdrs, args))
 
-#define AUTH_VALIDATE(auth, verfp)	\
-		((*((auth)->ah_ops->ah_validate))((auth), verfp))
-#define auth_validate(auth, verfp)	\
-		((*((auth)->ah_ops->ah_validate))((auth), verfp))
+#define AUTH_VALIDATE(auth, xid, verfp, resultsp) \
+		((*((auth)->ah_ops->ah_validate))((auth), xid, verfp, resultsp))
 
 #define AUTH_REFRESH(auth, msg)		\
 		((*((auth)->ah_ops->ah_refresh))(auth, msg))
-#define auth_refresh(auth, msg)		\
-		((*((auth)->ah_ops->ah_refresh))(auth, msg))
 
 #define AUTH_DESTROY(auth)		\
 		((*((auth)->ah_ops->ah_destroy))(auth))
-#define auth_destroy(auth)		\
-		((*((auth)->ah_ops->ah_destroy))(auth))
-
 
 __BEGIN_DECLS
 extern struct opaque_auth _null_auth;
@@ -357,5 +354,13 @@ __END_DECLS
 #define AUTH_DH		3		/* for Diffie-Hellman mechanism */
 #define AUTH_DES	AUTH_DH		/* for backward compatibility */
 #define AUTH_KERB	4		/* kerberos style */
+#define RPCSEC_GSS	6		/* RPCSEC_GSS */
+
+/*
+ * Pseudo auth flavors for RPCSEC_GSS.
+ */
+#define	RPCSEC_GSS_KRB5		390003
+#define	RPCSEC_GSS_KRB5I	390004
+#define	RPCSEC_GSS_KRB5P	390005
 
 #endif /* !_RPC_AUTH_H */