From 97d921c2c6d03603aaf2016be24072ef95dfe01b Mon Sep 17 00:00:00 2001
From: Samson-W <sccxboy@gmail.com>
Date: Wed, 17 Apr 2019 03:48:49 +0800
Subject: [PATCH] 1. Add method for if ipv6 is disabled. 2. Modify ipv6
 iptables rules check with check_ipv6_is_enable.

---
 ...ensure_firewall_set_protect_dos_attacks.sh | 56 +++++++++--
 ...ure_default_deny_firewall_policy_for_v6.sh | 30 ++++--
 ...e_loopback_traffic_is_configured_for_v6.sh | 98 +++++++++++--------
 ...l_rules_exist_for_all_open_ports_for_v6.sh | 78 ++++++++-------
 ...ished_connections_are_configured_for_v6.sh | 85 +++++++++-------
 lib/utils.sh                                  | 12 +++
 6 files changed, 229 insertions(+), 130 deletions(-)

diff --git a/bin/hardening/7.7.3_ensure_firewall_set_protect_dos_attacks.sh b/bin/hardening/7.7.3_ensure_firewall_set_protect_dos_attacks.sh
index bcb28c7..add2d95 100755
--- a/bin/hardening/7.7.3_ensure_firewall_set_protect_dos_attacks.sh
+++ b/bin/hardening/7.7.3_ensure_firewall_set_protect_dos_attacks.sh
@@ -18,26 +18,68 @@ HARDENING_LEVEL=2
 IPS4=$(which iptables)
 IPS6=$(which ip6tables)
 
+IPV4_RET=1
+IPV6_RET=1
+IPV6_ISENABLE=1
+
 # Quick note here : CIS recommends your iptables rules to be persistent. 
 # Do as you want, but this script does not handle this
 
 # This function will be called if the script status is on enabled / audit mode
 audit () {
-    if [ $(${IPS4} -S | grep -E "\-m.*limit" | grep -Ec "\-\-limit-burst") -eq 0 -o $(${IPS6} -S | grep -E "\-m.*limit" | grep -Ec "\-\-limit-burst") -eq 0 ]; then
-		crit "Ip4tables/Ip6tables is not set rules of protect DOS attacks!"
-		FNRET=1
+	# ipv4
+    if [ $(${IPS4} -S | grep -E "\-m.*limit" | grep -Ec "\-\-limit-burst") -eq 0 ]; then
+		info "Iptables is not set rules of protect DOS attacks!"
+		IPV4_RET=1
 	else
-		ok "Ip4tables/Ip6tables has set rules for protect DOS attacks!"
-		FNRET=0
+		info "Iptables has set rules for protect DOS attacks!"
+		IPV4_RET=0
+	fi
+	# ipv6
+	check_ipv6_is_enable
+	IPV6_ISENABLE=$FNRET
+	if [ $IPV6_ISENABLE = 0 ]; then 
+    	if [ $(${IPS6} -S | grep -E "\-m.*limit" | grep -Ec "\-\-limit-burst") -eq 0 ]; then
+			info "Ip6tables is not set rules of protect DOS attacks!"
+			IPV6_RET=1
+		else
+			info "Ip6tables has set rules for protect DOS attacks!"
+			IPV6_RET=0
+		fi
+	fi
+	if [ $IPV6_ISENABLE -eq 0 ]; then
+		if [ $IPV4_RET -eq 1 -o $IPV6_RET -eq 1 ]; then
+			crit "Iptables/ip6tables is not set rules of protect DOS attacks!"
+			FNRET=1
+		else
+			ok "Iptables/ip6tables has set rules for protect DOS attacks!"
+			FNRET=0
+		fi
+	else
+		if [ $IPV4_RET -eq 1 ]; then
+			crit "Iptables is not set rules of protect DOS attacks!"
+			FNRET=1
+		else
+			ok "Iptables has set rules for protect DOS attacks!"
+			FNRET=0
+		fi
 	fi
 }
 
 # This function will be called if the script status is on enabled mode
 apply () {
     if [ $FNRET = 0 ]; then
-        ok "Ip4tables/Ip6tables has set rules for protect DOS attacks!"
+		if [ $IPV6_ISENABLE -eq 0 ]; then
+        	ok "Iptables/Ip6tables has set rules for protect DOS attacks!"
+		else
+        	ok "Iptables has set rules for protect DOS attacks!"
+		fi
     else
-        warn "Ip4tables/Ip6tables is not set rules of protect DOS attacks! need the administrator to manually add it."
+		if [ $IPV6_ISENABLE -eq 0 ]; then
+        	warn "Iptables/Ip6tables is not set rules of protect DOS attacks! need the administrator to manually add it."
+		else
+        	warn "Iptables is not set rules of protect DOS attacks! need the administrator to manually add it."
+		fi
     fi
 }
 
diff --git a/bin/hardening/7.7.5.1_ensure_default_deny_firewall_policy_for_v6.sh b/bin/hardening/7.7.5.1_ensure_default_deny_firewall_policy_for_v6.sh
index d3b2d45..95ac7e4 100755
--- a/bin/hardening/7.7.5.1_ensure_default_deny_firewall_policy_for_v6.sh
+++ b/bin/hardening/7.7.5.1_ensure_default_deny_firewall_policy_for_v6.sh
@@ -16,25 +16,37 @@ set -u # One variable unset, it's over
 HARDENING_LEVEL=2
 
 IPS6=$(which ip6tables)
+IPV6_ENABLE=1
 
 # This function will be called if the script status is on enabled / audit mode
 audit () {
-    if [ $(${IPS6} -S | grep -c "\-P INPUT DROP") -eq 0 -o  $(${IPS4} -S | grep -c "\-P OUTPUT DROP") -eq 0 -o  $(${IPS4} -S | grep -c "\-P FORWARD DROP") -eq 0 ]; then
-		crit "Ip6tables: Firewall policy is not default deny!"
-		FNRET=1
+	check_ipv6_is_enable
+	IPV6_ENABLE=$FNRET
+	if [ $IPV6_ENABLE -eq 0 ]; then
+    	if [ $(${IPS6} -S | grep -c "\-P INPUT DROP") -eq 0 -o  $(${IPS4} -S | grep -c "\-P OUTPUT DROP") -eq 0 -o  $(${IPS4} -S | grep -c "\-P FORWARD DROP") -eq 0 ]; then
+			crit "Ip6tables: Firewall policy is not default deny!"
+			FNRET=1
+		else
+			ok "Ip6tables has set default deny for firewall policy!"
+			FNRET=0
+		fi
 	else
-		ok "Ip6tables has set default deny for firewall policy!"
+		ok "Ipv6 has set disabled, so pass."
 		FNRET=0
 	fi
 }
 
 # This function will be called if the script status is on enabled mode
 apply () {
-    if [ $FNRET = 0 ]; then
-        ok "Ip6tables has set default deny for firewall policy!"
-    else
-        warn "Ip6tables is not set default deny for firewall policy! need the administrator to manually add it. Howto set: ip6tables -P INPUT DROP; ip6tables -P OUTPUT DROP; ip6tables -P FORWARD DROP."
-    fi
+	if [ $IPV6_ENABLE -eq 0 ]; then
+    	if [ $FNRET = 0 ]; then
+        	ok "Ip6tables has set default deny for firewall policy!"
+    	else
+        	warn "Ip6tables is not set default deny for firewall policy! need the administrator to manually add it. Howto set: ip6tables -P INPUT DROP; ip6tables -P OUTPUT DROP; ip6tables -P FORWARD DROP."
+    	fi
+	else
+		ok "Ipv6 has set disabled, so pass."
+	fi
 }
 
 # This function will check config parameters required
diff --git a/bin/hardening/7.7.5.2_ensure_loopback_traffic_is_configured_for_v6.sh b/bin/hardening/7.7.5.2_ensure_loopback_traffic_is_configured_for_v6.sh
index 4a42ec6..5a1c3cf 100755
--- a/bin/hardening/7.7.5.2_ensure_loopback_traffic_is_configured_for_v6.sh
+++ b/bin/hardening/7.7.5.2_ensure_loopback_traffic_is_configured_for_v6.sh
@@ -19,61 +19,73 @@ INPUT_ACCEPT=1
 OUTPUT_ACCEPT=1
 INPUT_DENY=1
 IP6VERSION="IPS6"
+IPV6_ENABLE=1
 
 # This function will be called if the script status is on enabled / audit mode
 audit () {
-	# Check the loopback interface to accept INPUT traffic.
-	ensure_lo_traffic_input_is_accept $IP6VERSION
-	if [ $FNRET = 0 ]; then
-		INPUT_ACCEPT=0
-		info "Ip6tables loopback traffic INPUT has configured!"
+	check_ipv6_is_enable
+	IPV6_ENABLE=$FNRET
+	if [ $IPV6_ENABLE -eq 0 ]; then
+		# Check the loopback interface to accept INPUT traffic.
+		ensure_lo_traffic_input_is_accept $IP6VERSION
+		if [ $FNRET = 0 ]; then
+			INPUT_ACCEPT=0
+			info "Ip6tables loopback traffic INPUT has configured!"
+		else
+			INPUT_ACCEPT=1
+			info "Ip6tables: loopback traffic INPUT is not configured!"
+		fi 
+		# Check the loopback interface to accept OUTPUT traffic.
+		ensure_lo_traffic_output_is_accept $IP6VERSION
+		if [ $FNRET = 0 ]; then
+			OUTPUT_ACCEPT=0
+			info "Ip6tables loopback traffic OUTPUT has configured!"
+		else
+			OUTPUT_ACCEPT=1
+			info "Ip6tables: loopback traffic OUTPUT is not configured!"
+		fi 
+		# all other interfaces to deny traffic to the loopback network.
+		ensure_lo_traffic_other_if_input_is_deny $IP6VERSION
+		if [ $FNRET = 0 ]; then
+			INPUT_DENY=0
+			info "Ip6tables loopback traffic INPUT deny from other interfaces has configured!"
+		else
+			INPUT_DENY=1
+			info "Ip6tables: loopback traffic INPUT deny from other interfaces is not configured!"
+		fi 
+
+		if [ $INPUT_ACCEPT -eq 0 -a $OUTPUT_ACCEPT -eq -a $OUTPUT_ACCEPT -eq ]; then
+			ok "Loopback traffic rules were configured for v6!"
+		else
+			crit "Loopback traffic rules are not configured for v6!"
+		fi
 	else
-		INPUT_ACCEPT=1
-		info "Ip6tables: loopback traffic INPUT is not configured!"
-	fi 
-	# Check the loopback interface to accept OUTPUT traffic.
-	ensure_lo_traffic_output_is_accept $IP6VERSION
-	if [ $FNRET = 0 ]; then
-		OUTPUT_ACCEPT=0
-		info "Ip6tables loopback traffic OUTPUT has configured!"
-	else
-		OUTPUT_ACCEPT=1
-		info "Ip6tables: loopback traffic OUTPUT is not configured!"
-	fi 
-	# all other interfaces to deny traffic to the loopback network.
-	ensure_lo_traffic_other_if_input_is_deny $IP6VERSION
-	if [ $FNRET = 0 ]; then
-		INPUT_DENY=0
-		info "Ip6tables loopback traffic INPUT deny from other interfaces has configured!"
-	else
-		INPUT_DENY=1
-		info "Ip6tables: loopback traffic INPUT deny from other interfaces is not configured!"
-	fi 
-	if [ $INPUT_ACCEPT -eq 0 -a $OUTPUT_ACCEPT -eq -a $OUTPUT_ACCEPT -eq ]; then
-		ok "Loopback traffic rules were configured for v6!"
-	else
-		crit "Loopback traffic rules are not configured for v6!"
+		ok "Ipv6 has set disabled, so pass."
 	fi
 }
 
 # This function will be called if the script status is on enabled mode
 apply () {
-	if [ $INPUT_ACCEPT = 0 ]; then 
-		ok "Ip6tables loopback traffic INPUT has configured!"
-	else
-        warn "Ip6tables loopback traffic INPUT is not configured! need the administrator to manually add it. Howto set: ip6tables -A INPUT -i lo -j ACCEPT"
-	fi
+	if [ $IPV6_ENABLE -eq 0 ]; then
+		if [ $INPUT_ACCEPT = 0 ]; then 
+			ok "Ip6tables loopback traffic INPUT has configured!"
+		else
+        	warn "Ip6tables loopback traffic INPUT is not configured! need the administrator to manually add it. Howto set: ip6tables -A INPUT -i lo -j ACCEPT"
+		fi
 
-	if [ $OUTPUT_ACCEPT = 0 ]; then 
-		ok "Ip6tables loopback traffic OUTPUT has configured!"
-	else
-        warn "Ip6tables loopback traffic OUTPUT is not configured! need the administrator to manually add it. Howto set: ip6tables -A OUTPUT -o lo -j ACCEPT"
-	fi
+		if [ $OUTPUT_ACCEPT = 0 ]; then 
+			ok "Ip6tables loopback traffic OUTPUT has configured!"
+		else
+        	warn "Ip6tables loopback traffic OUTPUT is not configured! need the administrator to manually add it. Howto set: ip6tables -A OUTPUT -o lo -j ACCEPT"
+		fi
 
-	if [ $INPUT_DENY = 0 ]; then 
-		ok "Ip6tables loopback traffic INPUT deny from other interfaces has configured!"
+		if [ $INPUT_DENY = 0 ]; then 
+			ok "Ip6tables loopback traffic INPUT deny from other interfaces has configured!"
+		else
+        	warn "Ip6tables loopback traffic INPUT deny from 127.0.0.0/8 is not configured! need the administrator to manually add it. Howto set: ip6tables -A INPUT -s 127.0.0.0/8 -j DROP"
+		fi
 	else
-        warn "Ip6tables loopback traffic INPUT deny from 127.0.0.0/8 is not configured! need the administrator to manually add it. Howto set: ip6tables -A INPUT -s 127.0.0.0/8 -j DROP"
+		ok "Ipv6 has set disabled, so pass."
 	fi
 }
 
diff --git a/bin/hardening/7.7.5.3_ensure_firewall_rules_exist_for_all_open_ports_for_v6.sh b/bin/hardening/7.7.5.3_ensure_firewall_rules_exist_for_all_open_ports_for_v6.sh
index 4665557..2a498da 100755
--- a/bin/hardening/7.7.5.3_ensure_firewall_rules_exist_for_all_open_ports_for_v6.sh
+++ b/bin/hardening/7.7.5.3_ensure_firewall_rules_exist_for_all_open_ports_for_v6.sh
@@ -16,55 +16,65 @@ set -u # One variable unset, it's over
 HARDENING_LEVEL=2
 
 IPS6=$(which ip6tables)
+IPV6_ENABLE=1
 
 NETLISTENLIST="/dev/shm/7.7.5.3"
 PROTO_PORT="/dev/shm/proto_port_pair_v6"
 
 # This function will be called if the script status is on enabled / audit mode
 audit () {
-	# For ipv4 
 	rm -f $NETLISTENLIST
 	rm -f $PROTO_PORT
+	check_ipv6_is_enable
+	IPV6_ENABLE=$FNRET
 	# For ipv6
-	netstat -ln | egrep -w '^tcp6|^udp6' > $NETLISTENLIST
-	cat $NETLISTENLIST | while read LISTENING
-	do
-		PROTO_TYPE=$(echo ${LISTENING} | awk '{print $1}')
-		if [ "$PROTO_TYPE" == 'tcp6' ]; then
-			PROTO_TYPE="tcp"
+	if [ $IPV6_ENABLE -eq 0 ]; then
+		netstat -ln | egrep -w '^tcp6|^udp6' > $NETLISTENLIST
+		cat $NETLISTENLIST | while read LISTENING
+		do
+			PROTO_TYPE=$(echo ${LISTENING} | awk '{print $1}')
+			if [ "$PROTO_TYPE" == 'tcp6' ]; then
+				PROTO_TYPE="tcp"
+			fi
+			if [ "$PROTO_TYPE" == 'udp6' ]; then
+				PROTO_TYPE="udp"
+			fi
+			LISTEN_PORT=$(echo ${LISTENING} | awk '{print $4}' | awk -F: '{print $4}')
+			if [ $($IPS6 -S | grep "^\-A INPUT \-p $PROTO_TYPE" | grep -c "\-\-dport $LISTEN_PORT \-m state \-\-state NEW \-j ACCEPT") -ge 1 ]; then
+        		info "Service: protocol $PROTO_TYPE listening port $LISTEN_PORT was set ipv6 firewall rules."
+			else	
+				echo "${PROTO_TYPE} ${LISTEN_PORT}" >> $PROTO_PORT
+				info "Service: protocol $PROTO_TYPE listening port $LISTEN_PORT is not set ipv6 firewall rules."
+			fi
+		done
+		rm -f $NETLISTENLIST
+    	if [ -f $PROTO_PORT ]; then
+        	crit "Ip6tables is not set firewall rules exist for all open ports!"
+		else
+        	ok "Ip6tables has set firewall rules exist for all open ports!"
 		fi
-		if [ "$PROTO_TYPE" == 'udp6' ]; then
-			PROTO_TYPE="udp"
-		fi
-		LISTEN_PORT=$(echo ${LISTENING} | awk '{print $4}' | awk -F: '{print $4}')
-		if [ $($IPS6 -S | grep "^\-A INPUT \-p $PROTO_TYPE" | grep -c "\-\-dport $LISTEN_PORT \-m state \-\-state NEW \-j ACCEPT") -ge 1 ]; then
-        	info "Service: protocol $PROTO_TYPE listening port $LISTEN_PORT was set ipv6 firewall rules."
-		else	
-			echo "${PROTO_TYPE} ${LISTEN_PORT}" >> $PROTO_PORT
-			info "Service: protocol $PROTO_TYPE listening port $LISTEN_PORT is not set ipv6 firewall rules."
-		fi
-	done
-	rm -f $NETLISTENLIST
-    if [ -f $PROTO_PORT ]; then
-        crit "Ip6tables is not set firewall rules exist for all open ports!"
-	else
-        ok "Ip6tables has set firewall rules exist for all open ports!"
+	else	
+		ok "Ipv6 has set disabled, so pass."
 	fi
 }
 
 # This function will be called if the script status is on enabled mode
 apply () {
-    if [ -f $PROTO_PORT ]; then
-		cat $PROTO_PORT | while read NOSETPAIR
-		do
-			PROTO_TYPE=$(echo ${NOSETPAIR} | awk '{print $1}')
-			LISTEN_PORT=$(echo ${NOSETPAIR} | awk '{print $2}')
-			warn "Service: protocol $PROTO_TYPE listening port $LISTEN_PORT is not set firewall rules, need the administrator to manually add it. Howto set: ip6tables -A INPUT -p <protocol> --dport <port> -m state --state NEW -j ACCEPT"
-		done
-		rm -f $PROTO_PORT 
-    else
-        ok "Ip6tables has set firewall rules exist for all open ports!"
-    fi
+	if [ $IPV6_ENABLE -eq 0 ]; then
+    	if [ -f $PROTO_PORT ]; then
+			cat $PROTO_PORT | while read NOSETPAIR
+			do
+				PROTO_TYPE=$(echo ${NOSETPAIR} | awk '{print $1}')
+				LISTEN_PORT=$(echo ${NOSETPAIR} | awk '{print $2}')
+				warn "Service: protocol $PROTO_TYPE listening port $LISTEN_PORT is not set firewall rules, need the administrator to manually add it. Howto set: ip6tables -A INPUT -p <protocol> --dport <port> -m state --state NEW -j ACCEPT"
+			done
+			rm -f $PROTO_PORT 
+    	else
+        	ok "Ip6tables has set firewall rules exist for all open ports!"
+    	fi
+	else
+		ok "Ipv6 has set disabled, so pass."
+	fi
 }
 
 # This function will check config parameters required
diff --git a/bin/hardening/7.7.5.4_ensure_outbound_and_established_connections_are_configured_for_v6.sh b/bin/hardening/7.7.5.4_ensure_outbound_and_established_connections_are_configured_for_v6.sh
index cddf180..0ecf4c8 100755
--- a/bin/hardening/7.7.5.4_ensure_outbound_and_established_connections_are_configured_for_v6.sh
+++ b/bin/hardening/7.7.5.4_ensure_outbound_and_established_connections_are_configured_for_v6.sh
@@ -17,56 +17,67 @@ HARDENING_LEVEL=2
 
 PROTOCOL_LIST="tcp udp icmp"
 IP6VERSION="IPS6"
+IPV6_ENABLE=1
 
 RET_VALUE1=1
 RET_VALUE2=1
 
 # This function will be called if the script status is on enabled / audit mode
 audit () {
-	for protocol in $PROTOCOL_LIST
-	do
-		# Check INPUT with ESTABLISHED is config
-		check_input_with_established_is_accept "${protocol}" "$IP6VERSION"
-		if [ $FNRET = 0 ]; then 
-			RET_VALUE1=0
-			info "Portocol $protocol INPUT is conf"
-		else
-			RET_VALUE1=1
-			info "Portocol $protocol INPUT is not conf"
-		fi
-		# Check outbound is config
-		check_outbound_connect_is_accept "${protocol}" $IP6VERSION
-		if [ $FNRET = 0 ]; then 
-			RET_VALUE2=0
-			info "Portocol $protocol outbound is conf"
-		else
-			RET_VALUE2=1
-			info "Portocol $protocol outbound is not conf"
-		fi
-	done
+	check_ipv6_is_enable
+	IPV6_ENABLE=$FNRET
+	if [ $IPV6_ENABLE -eq 0 ]; then
+		for protocol in $PROTOCOL_LIST
+		do
+			# Check INPUT with ESTABLISHED is config
+			check_input_with_established_is_accept "${protocol}" "$IP6VERSION"
+			if [ $FNRET = 0 ]; then 
+				RET_VALUE1=0
+				info "Portocol $protocol INPUT is conf"
+			else
+				RET_VALUE1=1
+				info "Portocol $protocol INPUT is not conf"
+			fi
+			# Check outbound is config
+			check_outbound_connect_is_accept "${protocol}" $IP6VERSION
+			if [ $FNRET = 0 ]; then 
+				RET_VALUE2=0
+				info "Portocol $protocol outbound is conf"
+			else
+				RET_VALUE2=1
+				info "Portocol $protocol outbound is not conf"
+			fi
+		done
 
-	if [ $RET_VALUE1 -eq 0 -a $RET_VALUE2 -eq 0 ]; then
-		ok "Outbound and established connections are configured for v6."
+		if [ $RET_VALUE1 -eq 0 -a $RET_VALUE2 -eq 0 ]; then
+			ok "Outbound and established connections are configured for v6."
+		else
+			crit "Outbound and established connections are not configured for v6."
+		fi
 	else
-		crit "Outbound and established connections are not configured for v6."
+		ok "Ipv6 has set disabled, so pass."
 	fi
 }
 
 # This function will be called if the script status is on enabled mode
 apply () {
-	for protocol in $PROTOCOL_LIST
-	do
-		# Apply INPUT with ESTABLISHED 
-		check_input_with_established_is_accept "${protocol}" "$IP6VERSION"
-		if [ $FNRET = 1 ]; then 
-			warn "Portocol $protocol INPUT is not set, need the administrator to manually add it. Howto apply: ip6tables -A INPUT -p $protocol -m state --state ESTABLISHED -j ACCEPT"
-		fi
-		# Apply outbound 
-		check_outbound_connect_is_accept "${protocol}" "$IP6VERSION"
-		if [ $FNRET = 1 ]; then 
-			warn "Portocol $protocol outbound is not set, need the administrator to manually add it. Howto apply: ip6tables -A OUTPUT -p $protocol -m state --state NEW,ESTABLISHED -j ACCEPT"
-		fi
-	done
+	if [ $IPV6_ENABLE -eq 0 ]; then
+		for protocol in $PROTOCOL_LIST
+		do
+			# Apply INPUT with ESTABLISHED 
+			check_input_with_established_is_accept "${protocol}" "$IP6VERSION"
+			if [ $FNRET = 1 ]; then 
+				warn "Portocol $protocol INPUT is not set, need the administrator to manually add it. Howto apply: ip6tables -A INPUT -p $protocol -m state --state ESTABLISHED -j ACCEPT"
+			fi
+			# Apply outbound 
+			check_outbound_connect_is_accept "${protocol}" "$IP6VERSION"
+			if [ $FNRET = 1 ]; then 
+				warn "Portocol $protocol outbound is not set, need the administrator to manually add it. Howto apply: ip6tables -A OUTPUT -p $protocol -m state --state NEW,ESTABLISHED -j ACCEPT"
+			fi
+		done
+	else
+		ok "Ipv6 has set disabled, so pass."
+	fi
 }
 
 # This function will check config parameters required
diff --git a/lib/utils.sh b/lib/utils.sh
index e2ba418..512af2f 100644
--- a/lib/utils.sh
+++ b/lib/utils.sh
@@ -860,3 +860,15 @@ extend_touch_file()
 	fi
 }
 
+# Check ipv6 is enable
+check_ipv6_is_enable()
+{
+	if [ $(ip -6 addr | wc -l) -gt 0 ]; then
+		debug "Ipv6 is enabled."
+		FNRET=0
+	else
+		debug "Ipv6 is disabled."
+		FNRET=1
+	fi
+}
+