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, 51 insertions, 19 deletions

diff --git a/sys/rpc/clnt.h b/sys/rpc/clnt.h
index 03e3112..74d5813 100644
--- a/sys/rpc/clnt.h
+++ b/sys/rpc/clnt.h
@@ -118,6 +118,15 @@ struct rpc_err {
 typedef void rpc_feedback(int cmd, int procnum, void *);
 
 /*
+ * Timers used for the pseudo-transport protocol when using datagrams
+ */
+struct rpc_timers {
+	u_short		rt_srtt;	/* smoothed round-trip time */
+	u_short		rt_deviate;	/* estimated deviation */
+	u_long		rt_rtxcur;	/* current (backed-off) rto */
+};
+
+/*
  * A structure used with CLNT_CALL_EXT to pass extra information used
  * while processing an RPC call.
  */
@@ -125,6 +134,8 @@ struct rpc_callextra {
 	AUTH		*rc_auth;	/* auth handle to use for this call */
 	rpc_feedback	*rc_feedback;	/* callback for retransmits etc. */
 	void		*rc_feedback_arg; /* argument for callback */
+	struct rpc_timers *rc_timers;	  /* optional RTT timers */
+	struct rpc_err	rc_err;		/* detailed call status */
 };
 #endif
 
@@ -140,8 +151,8 @@ typedef struct __rpc_client {
 	struct clnt_ops {
 		/* call remote procedure */
 		enum clnt_stat	(*cl_call)(struct __rpc_client *,
-		    struct rpc_callextra *, rpcproc_t, xdrproc_t, void *,
-		    xdrproc_t, void *, struct timeval);
+		    struct rpc_callextra *, rpcproc_t,
+		    struct mbuf *, struct mbuf **, struct timeval);
 		/* abort a call */
 		void		(*cl_abort)(struct __rpc_client *);
 		/* get specific error code */
@@ -150,6 +161,8 @@ typedef struct __rpc_client {
 		/* frees results */
 		bool_t		(*cl_freeres)(struct __rpc_client *,
 					xdrproc_t, void *);
+		/* close the connection and terminate pending RPCs */
+		void		(*cl_close)(struct __rpc_client *);
 		/* destroy this structure */
 		void		(*cl_destroy)(struct __rpc_client *);
 		/* the ioctl() of rpc */
@@ -183,15 +196,6 @@ typedef struct __rpc_client {
 	char			*cl_tp;		/* device name */
 } CLIENT;
 
-/*
- * Timers used for the pseudo-transport protocol when using datagrams
- */
-struct rpc_timers {
-	u_short		rt_srtt;	/* smoothed round-trip time */
-	u_short		rt_deviate;	/* estimated deviation */
-	u_long		rt_rtxcur;	/* current (backed-off) rto */
-};
-
 /*      
  * Feedback values used for possible congestion and rate control
  */
@@ -222,6 +226,32 @@ struct rpc_timers {
 		CLNT_DESTROY(rh)
 
 /*
+ * void
+ * CLNT_CLOSE(rh);
+ * 	CLIENT *rh;
+ */
+#define	CLNT_CLOSE(rh)	((*(rh)->cl_ops->cl_close)(rh))
+
+enum clnt_stat clnt_call_private(CLIENT *, struct rpc_callextra *, rpcproc_t,
+    xdrproc_t, void *, xdrproc_t, void *, struct timeval);
+
+/*
+ * enum clnt_stat
+ * CLNT_CALL_MBUF(rh, ext, proc, mreq, mrepp, timeout)
+ * 	CLIENT *rh;
+ *	struct rpc_callextra *ext;
+ *	rpcproc_t proc;
+ *	struct mbuf *mreq;
+ *	struct mbuf **mrepp;
+ *	struct timeval timeout;
+ *
+ * Call arguments in mreq which is consumed by the call (even if there
+ * is an error). Results returned in *mrepp.
+ */
+#define	CLNT_CALL_MBUF(rh, ext, proc, mreq, mrepp, secs)	\
+	((*(rh)->cl_ops->cl_call)(rh, ext, proc, mreq, mrepp, secs))
+
+/*
  * enum clnt_stat
  * CLNT_CALL_EXT(rh, ext, proc, xargs, argsp, xres, resp, timeout)
  * 	CLIENT *rh;
@@ -234,8 +264,8 @@ struct rpc_timers {
  *	struct timeval timeout;
  */
 #define	CLNT_CALL_EXT(rh, ext, proc, xargs, argsp, xres, resp, secs)	\
-	((*(rh)->cl_ops->cl_call)(rh, ext, proc, xargs,		\
-		argsp, xres, resp, secs))
+	clnt_call_private(rh, ext, proc, xargs,				\
+		argsp, xres, resp, secs)
 #endif
 
 /*
@@ -250,12 +280,12 @@ struct rpc_timers {
  *	struct timeval timeout;
  */
 #ifdef _KERNEL
-#define	CLNT_CALL(rh, proc, xargs, argsp, xres, resp, secs)		\
-	((*(rh)->cl_ops->cl_call)(rh, NULL, proc, xargs,	\
-		argsp, xres, resp, secs))
-#define	clnt_call(rh, proc, xargs, argsp, xres, resp, secs)		\
-	((*(rh)->cl_ops->cl_call)(rh, NULL, proc, xargs,	\
-		argsp, xres, resp, secs))
+#define	CLNT_CALL(rh, proc, xargs, argsp, xres, resp, secs)	\
+	clnt_call_private(rh, NULL, proc, xargs,		\
+		argsp, xres, resp, secs)
+#define	clnt_call(rh, proc, xargs, argsp, xres, resp, secs)	\
+	clnt_call_private(rh, NULL, proc, xargs,		\
+		argsp, xres, resp, secs)
 #else
 #define	CLNT_CALL(rh, proc, xargs, argsp, xres, resp, secs)		\
 	((*(rh)->cl_ops->cl_call)(rh, proc, xargs,	\
@@ -340,6 +370,8 @@ struct rpc_timers {
 #define CLGET_INTERRUPTIBLE	24	/* set interruptible flag */
 #define CLSET_RETRIES		25	/* set retry count for reconnect */
 #define CLGET_RETRIES		26	/* get retry count for reconnect */
+#define CLSET_PRIVPORT		27	/* set privileged source port flag */
+#define CLGET_PRIVPORT		28	/* get privileged source port flag */
 #endif