--- sys/netinet/myloop_masklen.h
+++ sys/netinet/myloop_masklen.h
@@ -0,0 +1,7 @@
+#include "opt_myloop_masklen.h"
+
+#ifndef MYLOOP_MASKLEN
+#define	IN_MY_LOOP(i)		(((u_int32_t)(i) & IN_CLASSA_NET) == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
+#else
+#define	IN_MY_LOOP(i)		(((u_int32_t)(i) & (INADDR_BROADCAST << (32 - MYLOOP_MASKLEN))) == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
+#endif
--- sys/conf/options	17 Nov 2012 07:42:48 -0000	1.510.2.26
+++ sys/conf/options	30 Nov 2012 20:44:10 -0000
@@ -391,6 +391,8 @@
 XBONEHACK
 KRPC
 NFSLOCKD
+# For interconnect beetween kernels in claster
+MYLOOP_MASKLEN
 
 # Netgraph(4). Use option NETGRAPH to enable the base netgraph code.
 # Each netgraph node type can be either be compiled into the kernel
--- sys/netinet/in.c
+++ sys/netinet/in.c
@@ -46,6 +46,7 @@
 #include <net/route.h>
 
 #include <netinet/in.h>
+#include <netinet/myloop_masklen.h>
 #include <netinet/in_var.h>
 #include <netinet/in_pcb.h>
 
@@ -140,11 +141,11 @@
 	register u_long i = ntohl(in.s_addr);
 	register u_long net;
 
-	if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i))
+	if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i) || IN_MY_LOOP(i))
 		return (0);
 	if (IN_CLASSA(i)) {
 		net = i & IN_CLASSA_NET;
-		if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
+		if (net == 0)
 			return (0);
 	}
 	return (1);
--- sys/netinet/ip_input.c
+++ sys/netinet/ip_input.c
@@ -60,6 +60,7 @@
 #include <net/netisr.h>
 
 #include <netinet/in.h>
+#include <netinet/myloop_masklen.h>
 #include <netinet/in_systm.h>
 #include <netinet/in_var.h>
 #include <netinet/ip.h>
@@ -381,8 +382,9 @@
 	}
 
 	/* 127/8 must not appear on wire - RFC1122 */
-	if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
-	    (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
+        /* Local change: 127/MYLOOP_MASKLEN */
+        if (IN_MY_LOOP(ntohl(ip->ip_dst.s_addr)) ||
+            IN_MY_LOOP(ntohl(ip->ip_src.s_addr))) {
 		if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
 			ipstat.ips_badaddr++;
 			goto bad;
--- sys/netinet/ip_output.c
+++ sys/netinet/ip_output.c
@@ -52,6 +52,7 @@
 #include <net/route.h>
 
 #include <netinet/in.h>
+#include <netinet/myloop_masklen.h>
 #include <netinet/in_systm.h>
 #include <netinet/ip.h>
 #include <netinet/in_pcb.h>
@@ -733,8 +734,9 @@
 
 passout:
 	/* 127/8 must not appear on wire - RFC1122. */
-	if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
-	    (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
+        /* Local change: 127/MYLOOP_MASKLEN */
+        if (IN_MY_LOOP(ntohl(ip->ip_dst.s_addr)) ||
+            IN_MY_LOOP(ntohl(ip->ip_src.s_addr))) {
 		if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
 			ipstat.ips_badaddr++;
 			error = EADDRNOTAVAIL;