SVCAUTH_WRAP/SVCAUTH_UNWRAP

Server code lacks support for authenticator wrapping/unwrapping, which
is particularly useful when using GSS.

Verified for both tcp & udp using a trivial RPC server against an MIT
Krb5 client.

Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

5 files changed, 83 insertions, 19 deletions

diff --git a/src/svc.c b/src/svc.c
index b4a63d0..08cd6c9 100644
--- a/src/svc.c
+++ b/src/svc.c
@@ -77,9 +77,6 @@ static struct svc_callout
 
 extern rwlock_t svc_lock;
 extern rwlock_t svc_fd_lock;
-#ifdef HAVE_LIBGSSAPI
-extern struct svc_auth_ops svc_auth_gss_ops;
-#endif
 
 static struct svc_callout *svc_find (rpcprog_t, rpcvers_t,
 				     struct svc_callout **, char *);
@@ -717,11 +714,9 @@ svc_getreq_common (fd)
 	  SVC_DESTROY (xprt);
 	  break;
 	}
-    else if ((xprt->xp_auth != NULL) 
-#ifdef HAVE_LIBGSSAPI
-	  	&& (xprt->xp_auth->svc_ah_ops != &svc_auth_gss_ops)
-#endif
-	) {
+    else if ((xprt->xp_auth != NULL) &&
+	     (xprt->xp_auth->svc_ah_private == NULL))
+	{
 	  xprt->xp_auth = NULL;
 	}
     }
diff --git a/src/svc_auth_unix.c b/src/svc_auth_unix.c
index ce83859..9585069 100644
--- a/src/svc_auth_unix.c
+++ b/src/svc_auth_unix.c
@@ -43,6 +43,8 @@
 
 #include <rpc/rpc.h>
 
+extern SVCAUTH svc_auth_none;
+
 /*
  * Unix longhand authenticator
  */
@@ -67,6 +69,8 @@ _svcauth_unix(rqst, msg)
 	assert(rqst != NULL);
 	assert(msg != NULL);
 
+	rqst->rq_xprt->xp_auth = &svc_auth_none;
+
 	area = (struct area *) rqst->rq_clntcred;
 	aup = &area->area_aup;
 	aup->aup_machname = area->area_machname;
@@ -142,5 +146,6 @@ _svcauth_short(rqst, msg)
 	struct svc_req *rqst;
 	struct rpc_msg *msg;
 {
+	rqst->rq_xprt->xp_auth = &svc_auth_none;
 	return (AUTH_REJECTEDCRED);
 }
diff --git a/src/svc_dg.c b/src/svc_dg.c
index 66a56ee..5ef9df2 100644
--- a/src/svc_dg.c
+++ b/src/svc_dg.c
@@ -134,6 +134,7 @@ svc_dg_create(fd, sendsize, recvsize)
 	su->su_cache = NULL;
 	xprt->xp_fd = fd;
 	xprt->xp_p2 = su;
+	xprt->xp_auth = NULL;
 	xprt->xp_verf.oa_base = su->su_verfbody;
 	svc_dg_ops(xprt);
 	xprt->xp_rtaddr.maxlen = sizeof (struct sockaddr_storage);
@@ -234,10 +235,27 @@ svc_dg_reply(xprt, msg)
 	bool_t stat = FALSE;
 	size_t slen;
 
+	xdrproc_t xdr_results;
+	caddr_t xdr_location;
+	bool_t has_args;
+
+	if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
+	    msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
+		has_args = TRUE;
+		xdr_results = msg->acpted_rply.ar_results.proc;
+		xdr_location = msg->acpted_rply.ar_results.where;
+
+		msg->acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
+		msg->acpted_rply.ar_results.where = NULL;
+	} else
+		has_args = FALSE;
+
 	xdrs->x_op = XDR_ENCODE;
 	XDR_SETPOS(xdrs, 0);
 	msg->rm_xid = su->su_xid;
-	if (xdr_replymsg(xdrs, msg)) {
+	if (xdr_replymsg(xdrs, msg) &&
+	    (!has_args ||
+	     (SVCAUTH_WRAP(xprt->xp_auth, xdrs, xdr_results, xdr_location)))) {
 		struct msghdr *msg = &su->su_msghdr;
 		struct iovec iov;
 
@@ -264,7 +282,12 @@ svc_dg_getargs(xprt, xdr_args, args_ptr)
 	xdrproc_t xdr_args;
 	void *args_ptr;
 {
-	return (*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr);
+	if (! SVCAUTH_UNWRAP(xprt->xp_auth, &(su_data(xprt)->su_xdrs),
+			     xdr_args, args_ptr)) {
+		(void)svc_freeargs(xprt, xdr_args, args_ptr);
+		return FALSE;
+	}
+	return TRUE;
 }
 
 static bool_t
@@ -288,6 +311,10 @@ svc_dg_destroy(xprt)
 	xprt_unregister(xprt);
 	if (xprt->xp_fd != -1)
 		(void)close(xprt->xp_fd);
+	if (xprt->xp_auth != NULL) {
+		SVCAUTH_DESTROY(xprt->xp_auth);
+		xprt->xp_auth = NULL;
+	}
 	XDR_DESTROY(&(su->su_xdrs));
 	(void) mem_free(rpc_buffer(xprt), su->su_iosz);
 	(void) mem_free(su, sizeof (*su));
diff --git a/src/svc_vc.c b/src/svc_vc.c
index 87406f1..74632e2 100644
--- a/src/svc_vc.c
+++ b/src/svc_vc.c
@@ -172,6 +172,7 @@ svc_vc_create(fd, sendsize, recvsize)
 	xprt->xp_p1 = r;
 	xprt->xp_p2 = NULL;
 	xprt->xp_p3 = NULL;
+	xprt->xp_auth = NULL;
 	xprt->xp_verf = _null_auth;
 	svc_vc_rendezvous_ops(xprt);
 	xprt->xp_port = (u_short)-1;	/* It is the rendezvouser */
@@ -283,6 +284,7 @@ makefd_xprt(fd, sendsize, recvsize)
 	xdrrec_create(&(cd->xdrs), sendsize, recvsize,
 	    xprt, read_vc, write_vc);
 	xprt->xp_p1 = cd;
+	xprt->xp_auth = NULL;
 	xprt->xp_verf.oa_base = cd->verf_body;
 	svc_vc_ops(xprt);  /* truely deals with calls */
 	xprt->xp_port = 0;  /* this is a connection, not a rendezvouser */
@@ -412,6 +414,10 @@ __svc_vc_dodestroy(xprt)
 		XDR_DESTROY(&(cd->xdrs));
 		mem_free(cd, sizeof(struct cf_conn));
 	}
+	if (xprt->xp_auth != NULL) {
+		SVCAUTH_DESTROY(xprt->xp_auth);
+		xprt->xp_auth = NULL;
+	}
 	if (xprt->xp_rtaddr.buf)
 		mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.maxlen);
 	if (xprt->xp_ltaddr.buf)
@@ -632,8 +638,13 @@ svc_vc_getargs(xprt, xdr_args, args_ptr)
 
 	assert(xprt != NULL);
 	/* args_ptr may be NULL */
-	return ((*xdr_args)(&(((struct cf_conn *)(xprt->xp_p1))->xdrs),
-	    args_ptr));
+
+	if (! SVCAUTH_UNWRAP(xprt->xp_auth,
+			     &(((struct cf_conn *)(xprt->xp_p1))->xdrs),
+			     xdr_args, args_ptr)) {
+		return FALSE;  
+	}
+	return TRUE;
 }
 
 static bool_t
@@ -662,15 +673,35 @@ svc_vc_reply(xprt, msg)
 	XDR *xdrs;
 	bool_t rstat;
 
+	xdrproc_t xdr_results;
+	caddr_t xdr_location;
+	bool_t has_args;
+
 	assert(xprt != NULL);
 	assert(msg != NULL);
 
 	cd = (struct cf_conn *)(xprt->xp_p1);
 	xdrs = &(cd->xdrs);
 
+	if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
+	    msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
+		has_args = TRUE;
+		xdr_results = msg->acpted_rply.ar_results.proc;
+		xdr_location = msg->acpted_rply.ar_results.where;
+
+		msg->acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
+		msg->acpted_rply.ar_results.where = NULL;
+	} else
+		has_args = FALSE;
+
 	xdrs->x_op = XDR_ENCODE;
 	msg->rm_xid = cd->x_id;
-	rstat = xdr_replymsg(xdrs, msg);
+	rstat = FALSE;
+	if (xdr_replymsg(xdrs, msg) &&
+	    (!has_args ||
+	     (SVCAUTH_WRAP(xprt->xp_auth, xdrs, xdr_results, xdr_location)))) {
+		rstat = TRUE;
+	}
 	(void)xdrrec_endofrecord(xdrs, TRUE);
 	return (rstat);
 }
diff --git a/tirpc/rpc/svc_auth.h b/tirpc/rpc/svc_auth.h
index 659e90c..14269d1 100644
--- a/tirpc/rpc/svc_auth.h
+++ b/tirpc/rpc/svc_auth.h
@@ -44,17 +44,23 @@
 /*
  * Interface to server-side authentication flavors.
  */
-typedef struct {
+typedef struct SVCAUTH {
 	struct svc_auth_ops {
-		int   (*svc_ah_wrap)(void);
-		int   (*svc_ah_unwrap)(void);
-		int   (*svc_ah_destroy)(void);
+		int     (*svc_ah_wrap)(struct SVCAUTH *, XDR *, xdrproc_t,
+				       caddr_t);
+		int     (*svc_ah_unwrap)(struct SVCAUTH *, XDR *, xdrproc_t,
+					 caddr_t);
+		int     (*svc_ah_destroy)(struct SVCAUTH *);
 		} *svc_ah_ops;
 	caddr_t svc_ah_private;
 } SVCAUTH;
 
-#define SVCAUTH_DESTROY(cred)		((*(cred)->svc_ah_ops->svc_ah_destroy)())
-#define svcauth_destroy(cred)		((*(cred)->svc_ah_ops->svc_ah_destroy)())
+#define SVCAUTH_WRAP(auth, xdrs, xfunc, xwhere) \
+	((*((auth)->svc_ah_ops->svc_ah_wrap))(auth, xdrs, xfunc, xwhere))
+#define SVCAUTH_UNWRAP(auth, xdrs, xfunc, xwhere) \
+	((*((auth)->svc_ah_ops->svc_ah_unwrap))(auth, xdrs, xfunc, xwhere))
+#define SVCAUTH_DESTROY(auth) \
+	((*((auth)->svc_ah_ops->svc_ah_destroy))(auth))
 
 /*
  * Server side authenticator