diff --git a/refpolicy/support/gennetfilter.py b/refpolicy/support/gennetfilter.py
new file mode 100644
index 0000000..ca9532a
--- /dev/null
+++ b/refpolicy/support/gennetfilter.py
@@ -0,0 +1,105 @@
+import re
+
+NETPORT = re.compile("^network_port\(\s*\w+\s*(\s*,\s*\w+\s*,\s*\w+\s*,\s*\w+\s*)+\s*\)\s*$")
+
+DEFAULT_PACKET = "packet_t"
+PACKET_INPUT = "_server_packet_t"
+PACKET_OUTPUT = "_client_packet_t"
+
+packets = []
+
+class Port:
+	def __init__(self, proto, num, mls_sens, mcs_cats=""):
+		# protocol of the port
+		self.proto = proto
+
+		# port number
+		self.num = num
+
+		# MLS sensitivity
+		self.mls_sens = mls_sens
+
+		# MCS categories
+		# not currently supported, so we always get s0
+		if mcs_cats == "":
+			self.mcs_cats = "s0"
+		else
+			self.mcs_cats = "s0:"+mcs_cats
+
+class Packet:
+	def __init__(self, prefix, ports):
+		# prefix
+		self.prefix = prefix
+
+		# A list of Ports
+		self.ports = ports
+
+def print_input_rules():
+	print "-A selinux_new_input -j SECMARK --selctx system_u:object_r:"+DEFAULT_PACKET
+	for i in packets:
+		for j in i.ports:
+			output_line="-A selinux_new_input -p "+j.proto+" --dport "+j.num+" -j SECMARK --selctx system_u:object_r:"+i.prefix+PACKET_INPUT
+
+	print "-A selinux_new_input -j CONNSECMARK --save"
+	print "-A selinux_new_input -j RETURN"
+
+def print_output_rules():
+	print "-A selinux_new_output -j SECMARK --selctx system_u:object_r:"+DEFAULT_PACKET
+	for i in packets:
+		for j in i.ports:
+			print "-A selinux_new_output -p "+j.proto+" --dport "+j.num+" -j SECMARK --selctx system_u:object_r:"+i.prefix+PACKET_OUTPUT
+
+	print "-A selinux_new_output -j CONNSECMARK --save"
+	print "-A selinux_new_output -j RETURN"
+
+def parse_corenet(file_name):
+	corenet_te_in = open(file_name, "r")
+
+	while True:
+		corenet_line = corenet_te_in.readline()
+
+		# If EOF has been reached:
+		if not corenet_line:
+			break
+
+		if NETPORT.match(corenet_line):
+			corenet_line = corenet_line.strip();
+
+			# parse out the parameters
+			parms = re.split('\W+',corenet_line[13:-1])
+			name = parms[0]
+			del parms[0];
+
+			ports = []
+			while len(parms) > 0:
+				# add a port combination.
+				ports.append(Port(parms[0],parms[1],parms[2]))
+				del parms[:3]
+
+			packets.append(Packet(name,ports))
+		
+	corenet_te_in.close()
+
+def write_netfilter_config():
+	print "*mangle"
+	print ":PREROUTING ACCEPT [0:0]"
+	print ":INPUT ACCEPT [0:0]"
+	print ":FORWARD ACCEPT [0:0]"
+	print ":OUTPUT ACCEPT [0:0]"
+	print ":POSTROUTING ACCEPT [0:0]"
+	print ":selinux_input [0:0]"
+	print ":selinux_output [0:0]"
+	print ":selinux_new_input [0:0]"
+	print ":selinux_new_output [0:0]"
+	print "-A INPUT -j selinux_input"
+	print "-A OUTPUT -j selinux_output"
+	print "-A selinux_input -m state --state NEW -j selinux_new_input"
+	print "-A selinux_input -m state --state RELATED,ESTABLISHED -j CONNSECMARK --restore"
+	print "-A selinux_output -m state --state NEW -j selinux_new_output"
+	print "-A selinux_output -m state --state RELATED,ESTABLISHED -j CONNSECMARK --restore"
+	print_input_rules()
+	print_output_rules()
+	print "COMMIT"
+
+parse_corenet("policy/modules/kernel/corenetwork.te.in")
+write_netfilter_config()