--- sys/conf/files.orig	Wed Apr 19 16:52:15 2000
+++ sys/conf/files	Wed Apr 26 11:53:24 2000
@@ -699,6 +699,7 @@
 netinet/ip_mroute.c	optional inet
 netinet/ip_output.c	optional inet
 netinet/raw_ip.c	optional inet
+netinet/gre.c		optional gre 
 netinet/tcp_debug.c	optional tcpdebug
 netinet/tcp_input.c	optional inet
 netinet/tcp_output.c	optional inet

--- sys/conf/options.orig	Wed Apr 19 16:52:15 2000
+++ sys/conf/options	Wed Apr 26 11:57:00 2000
@@ -256,6 +256,7 @@
 IPV6FIREWALL_VERBOSE_LIMIT	opt_ip6fw.h
 IPV6FIREWALL_DEFAULT_TO_ACCEPT	opt_ip6fw.h
 IPSTEALTH
+GRE			opt_gre.h
 IPX			opt_ipx.h
 IPXIP			opt_ipx.h
 IPTUNNEL		opt_ipx.h

--- sys/netinet/in_proto.c.orig	Sun Feb 13 06:32:00 2000
+++ sys/netinet/in_proto.c	Wed Apr 26 11:58:25 2000
@@ -38,6 +38,7 @@
 #include "opt_ipx.h"
 #include "opt_ipsec.h"
 #include "opt_inet6.h"
+#include "opt_gre.h"
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -114,11 +115,19 @@
   &tcp_usrreqs
 },
 { SOCK_RAW,	&inetdomain,	IPPROTO_RAW,	PR_ATOMIC|PR_ADDR,
-  rip_input,	0,		rip_ctlinput,	rip_ctloutput,
+  rip_input,	0,		rip_ctlinput,   rip_ctloutput,
   0,
   0,		0,		0,		0,
   &rip_usrreqs
 },
+#ifdef GRE
+{ SOCK_RAW,     &inetdomain,    IPPROTO_GRE,    PR_ATOMIC|PR_ADDR,
+  gre_input,	0,              0,		rip_ctloutput,
+  0,
+  0,            0,              0,              0,
+  &rip_usrreqs
+},
+#endif
 { SOCK_RAW,	&inetdomain,	IPPROTO_ICMP,	PR_ATOMIC|PR_ADDR,
   icmp_input,	0,		0,		rip_ctloutput,
   0,

--- sys/netinet/ip_var.h.orig	Wed Dec 29 07:41:02 1999
+++ sys/netinet/ip_var.h	Wed Apr 26 16:18:44 2000
@@ -171,6 +171,7 @@
 void	 rip_init __P((void));
 void	 rip_input __P((struct mbuf *, int, int));
 int	 rip_output __P((struct mbuf *, struct socket *, u_long));
+void	gre_input __P((struct mbuf *, int, int));
 void	ipip_input __P((struct mbuf *, int, int));
 void	rsvp_input __P((struct mbuf *, int, int));
 int	ip_rsvp_init __P((struct socket *));