Merge pull request #520 from jack9603301/nptv6

nptv6: T2518: Initial support for nat66 (NPT)

11 files changed, 738 insertions, 69 deletions

diff --git a/data/configd-include.json b/data/configd-include.json
index 318ab0e14..345460700 100644
--- a/data/configd-include.json
+++ b/data/configd-include.json
@@ -28,6 +28,7 @@
 "ipsec-settings.py",
 "lldp.py",
 "nat.py",
+"nat66.py",
 "ntp.py",
 "policy-local-route.py",
 "protocols_bgp.py",
diff --git a/data/templates/firewall/nftables-nat.tmpl b/data/templates/firewall/nftables-nat.tmpl
index 5480447f2..499733225 100644
--- a/data/templates/firewall/nftables-nat.tmpl
+++ b/data/templates/firewall/nftables-nat.tmpl
@@ -118,7 +118,7 @@
 {% endmacro %}
 
 # Start with clean NAT table
-flush table nat
+flush table ip nat
 {% if helper_functions == 'remove' %}
 {# NAT if going to be disabled - remove rules and targets from nftables #}
 {%   set base_command = 'delete rule ip raw' %}
diff --git a/data/templates/firewall/nftables-nat66.tmpl b/data/templates/firewall/nftables-nat66.tmpl
new file mode 100644
index 000000000..b1a8f7a16
--- /dev/null
+++ b/data/templates/firewall/nftables-nat66.tmpl
@@ -0,0 +1,85 @@
+#!/usr/sbin/nft -f
+
+{% macro nptv6_rule(rule,config, chain) %}
+{%     set src_prefix  = "ip6 saddr " + config.source.prefix if config.source is defined and config.source.prefix is defined and config.source.prefix is not none  %}
+{%     set dest_address  = "ip6 daddr " + config.destination.address if config.destination is defined and config.destination.address is defined and config.destination.address is not none %}
+{%   if chain == "PREROUTING" %}
+{%     set interface = " iifname \"" + config.inbound_interface + "\"" if config.inbound_interface is defined and config.inbound_interface != 'any' else '' %}
+{%     if config.translation.address | is_ip_network %}
+{#       support 1:1 network translation #}
+{%       set dnat_type = "dnat prefix to " %}
+{%     else   %}
+{%       set dnat_type = "dnat to " %}
+{%     endif %}
+{%     set trns_address = dnat_type + config.translation.address if config.translation is defined and config.translation.address is defined and config.translation.address is not none  %}
+{%   elif chain == "POSTROUTING" %}
+{%     set interface = " oifname \"" + config.outbound_interface + "\"" if config.outbound_interface is defined else '' %}
+{%     set trns_prefix = "snat prefix to " + config.translation.prefix if config.translation is defined and config.translation.prefix is defined and config.translation.prefix is not none %}
+{%   endif %}
+{%   set comment   = "NPT-NAT-" + rule %}
+{%   if rule.log %}
+{%     set base_log = "[NPT-DST-" + rule %}
+{%     set log = base_log + "]" %}
+{%   endif %}
+{%   set output = "add rule ip6 nat " + chain + interface %}
+{#   Count packets #}
+{%     set output = output + " counter" %}
+{#   Special handling of log option, we must repeat the entire rule before the #}
+{#   NAT translation options are added, this is essential                      #}
+{%   if log %}
+{%     set log_output = output + " log prefix \"" + log + "\" comment \"" + comment + "\"" %}
+{%   endif %}
+{%   if src_prefix %}
+{%     set output = output + " " + src_prefix %}
+{%   endif %}
+{%   if dest_address %}
+{%     set output = output + " " + dest_address %}
+{%   endif %}
+{%   if trns_prefix %}
+{%     set output = output + " " + trns_prefix %}
+{%   endif %}
+{%   if trns_address %}
+{%     set output = output + " " + trns_address %}
+{%   endif %}
+{%   if comment %}
+{%     set output = output + " comment \"" + comment + "\"" %}
+{%   endif %}
+{{ log_output if log_output }}
+{{ output }}
+{% endmacro %}
+
+# Start with clean NAT table
+flush table ip6 nat
+{% if helper_functions == 'remove' %}
+{# NAT if going to be disabled - remove rules and targets from nftables #}
+{%   set base_command = "delete rule ip6 raw" %}
+{{base_command}} PREROUTING handle {{ pre_ct_conntrack }}
+{{base_command}} OUTPUT handle {{ out_ct_conntrack }}
+
+delete chain ip6 raw NAT_CONNTRACK
+
+{% elif helper_functions == 'add' %}
+{# NAT if enabled - add targets to nftables #}
+add chain ip6 raw NAT_CONNTRACK
+add rule ip6 raw NAT_CONNTRACK counter accept
+{%   set base_command = "add rule ip6 raw" %}
+{{ base_command }} PREROUTING position {{ pre_ct_conntrack }} counter jump NAT_CONNTRACK
+{{ base_command }} OUTPUT     position {{ out_ct_conntrack }} counter jump NAT_CONNTRACK
+{% endif %}
+
+#
+# Destination NAT66 rules build up here
+#
+{% if destination is defined and destination.rule is defined and destination.rule is not none %}
+{%   for rule, config in destination.rule.items() if config.disable is not defined %}
+{{ nptv6_rule(rule, config, 'PREROUTING') }}
+{%   endfor %}
+{% endif %}
+#
+# Source NAT66 rules build up here
+#
+{% if source is defined and source.rule is defined and source.rule is not none %}
+{%   for rule, config in source.rule.items() if config.disable is not defined %}
+{{ nptv6_rule(rule, config, 'POSTROUTING') }}
+{%   endfor %}
+{% endif %}
diff --git a/data/templates/proxy-ndp/ndppd.conf.tmpl b/data/templates/proxy-ndp/ndppd.conf.tmpl
new file mode 100644
index 000000000..0137d8135
--- /dev/null
+++ b/data/templates/proxy-ndp/ndppd.conf.tmpl
@@ -0,0 +1,44 @@
+########################################################
+#
+# autogenerated by nat66.py
+#
+#   The configuration file must define one upstream
+#   interface.
+#
+#   For some services, such as nat66, because it runs
+#    stateless, it needs to rely on NDP Proxy to respond 
+#   to NDP requests.
+#
+#   When using nat66 source rules, NDP Proxy needs 
+#   to be enabled
+#
+########################################################
+
+{% set global = namespace(ndppd_interfaces = [],ndppd_prefixs = []) %}
+{% if source is defined and source.rule is defined and source.rule is not none %}
+{%   for rule, config in source.rule.items() if config.disable is not defined %}
+{%     if config.outbound_interface is defined %}
+{%         if config.outbound_interface not in global.ndppd_interfaces %}
+{%             set global.ndppd_interfaces = global.ndppd_interfaces + [config.outbound_interface] %}
+{%         endif   %}
+{%         if config.translation.prefix is defined  %}
+{%             set global.ndppd_prefixs = global.ndppd_prefixs + [{'interface':config.outbound_interface,'rule':config.translation.prefix}] %}
+{%         endif    %}
+{%     endif    %}
+{%   endfor %}
+{% endif %}
+
+{% for interface in global.ndppd_interfaces %}
+proxy {{ interface }} {
+    router yes
+    timeout 500
+    ttl 30000
+{%  for map in global.ndppd_prefixs %}
+{%     if map.interface == interface %}
+    rule {{ map.rule }} {
+        static
+    }
+{%     endif  %}
+{%  endfor   %}
+}
+{% endfor %} 
diff --git a/debian/control b/debian/control
index d0ba72bcf..2c8ee3d43 100644
--- a/debian/control
+++ b/debian/control
@@ -129,7 +129,8 @@ Depends:
   wide-dhcpv6-client,
   wireguard-tools,
   wireless-regdb,
-  wpasupplicant (>= 0.6.7)
+  wpasupplicant (>= 0.6.7),
+  ndppd
 Description: VyOS configuration scripts and data
  VyOS configuration scripts, interface definitions, and everything
 
diff --git a/interface-definitions/nat.xml.in b/interface-definitions/nat.xml.in
index d6bed5b27..3cff8abc9 100644
--- a/interface-definitions/nat.xml.in
+++ b/interface-definitions/nat.xml.in
@@ -56,73 +56,6 @@
           </tagNode>
         </children>
       </node>
-      <node name="nptv6">
-        <properties>
-          <help>IPv6-to-IPv6 Network Prefix Translation Settings</help>
-        </properties>
-        <children>
-          <tagNode name="rule">
-            <properties>
-              <help>NPTv6 rule number</help>
-              <valueHelp>
-                <format>1-999999</format>
-                <description>Number for this rule</description>
-              </valueHelp>
-              <constraint>
-                <validator name="numeric" argument="--range 1-999999"/>
-              </constraint>
-              <constraintErrorMessage>NAT rule number must be between 1 and 999999</constraintErrorMessage>
-            </properties>
-            <children>
-              <leafNode name="description">
-                <properties>
-                  <help>Rule description</help>
-                </properties>
-              </leafNode>
-              #include <include/generic-disable-node.xml.i>
-              #include <include/nat-interface.xml.i>
-              <node name="source">
-                <properties>
-                  <help>IPv6 source prefix options</help>
-                </properties>
-                <children>
-                  <leafNode name="prefix">
-                    <properties>
-                      <help>IPv6 prefix to be translated</help>
-                      <valueHelp>
-                        <format>ipv6net</format>
-                        <description>IPv6 prefix</description>
-                      </valueHelp>
-                      <constraint>
-                        <validator name="ipv6-prefix"/>
-                      </constraint>
-                    </properties>
-                  </leafNode>
-                </children>
-              </node>
-              <node name="translation">
-                <properties>
-                  <help>Translated IPv6 prefix options</help>
-                </properties>
-                <children>
-                  <leafNode name="prefix">
-                    <properties>
-                      <help>IPv6 prefix to translate to</help>
-                      <valueHelp>
-                        <format>ipv6net</format>
-                        <description>IPv6 prefix</description>
-                      </valueHelp>
-                      <constraint>
-                        <validator name="ipv6-prefix"/>
-                      </constraint>
-                    </properties>
-                  </leafNode>
-                </children>
-              </node>
-            </children>
-          </tagNode>
-        </children>
-      </node>
       <node name="source">
         <properties>
           <help>Source NAT settings</help>
diff --git a/interface-definitions/nat66.xml.in b/interface-definitions/nat66.xml.in
new file mode 100644
index 000000000..b45ebc0a8
--- /dev/null
+++ b/interface-definitions/nat66.xml.in
@@ -0,0 +1,192 @@
+<?xml version="1.0"?>
+<interfaceDefinition>
+  <node name="nat66" owner="${vyos_conf_scripts_dir}/nat66.py">
+    <properties>
+      <help>IPv6-to-IPv6 Network Prefix Translation (NAT66/NPT) Settings</help>
+      <priority>220</priority>
+    </properties>
+    <children>
+      <node name="source">
+        <properties>
+          <help>Prefix mapping of IPv6 source address translation</help>
+        </properties>
+        <children>
+          <tagNode name="rule">
+            <properties>
+              <help>Source NAT66 rule number</help>
+              <valueHelp>
+                <format>1-999999</format>
+                <description>Number for this rule</description>
+              </valueHelp>
+              <constraint>
+                <validator name="numeric" argument="--range 1-999999"/>
+              </constraint>
+              <constraintErrorMessage>NAT66 rule number must be between 1 and 999999</constraintErrorMessage>
+            </properties>
+            <children>
+              <leafNode name="description">
+                <properties>
+                  <help>Rule description</help>
+                </properties>
+              </leafNode>
+              <leafNode name="disable">
+                <properties>
+                  <help>Disable NAT66 rule</help>
+                  <valueless/>
+                </properties>
+              </leafNode>
+              <leafNode name="log">
+                <properties>
+                  <help>NAT66 rule logging</help>
+                  <valueless/>
+                </properties>
+              </leafNode>
+              <leafNode name="outbound-interface">
+                <properties>
+                  <help>Outbound interface of NAT66 traffic</help>
+                  <completionHelp>
+                    <script>${vyos_completion_dir}/list_interfaces.py</script>
+                  </completionHelp>
+                </properties>
+              </leafNode>
+              <node name="source">
+                <properties>
+                  <help>IPv6 source prefix options</help>
+                </properties>
+                <children>
+                  <leafNode name="prefix">
+                    <properties>
+                      <help>IPv6 prefix to be translated</help>
+                      <valueHelp>
+                        <format>ipv6net</format>
+                        <description>IPv6 prefix</description>
+                      </valueHelp>
+                      <constraint>
+                        <validator name="ipv6-prefix"/>
+                      </constraint>
+                    </properties>
+                  </leafNode>
+                </children>
+              </node>
+              <node name="translation">
+                <properties>
+                  <help>Translated IPv6 prefix options</help>
+                </properties>
+                <children>
+                  <leafNode name="prefix">
+                    <properties>
+                      <help>IPv6 prefix to translate to</help>
+                      <valueHelp>
+                        <format>ipv6net</format>
+                        <description>IPv6 prefix</description>
+                      </valueHelp>
+                      <constraint>
+                        <validator name="ipv6-prefix"/>
+                      </constraint>
+                    </properties>
+                  </leafNode>
+                </children>
+              </node>
+            </children>
+          </tagNode>
+        </children>
+      </node>
+      <node name="destination">
+        <properties>
+          <help>Prefix mapping for IPv6 destination address translation</help>
+        </properties>
+        <children>
+          <tagNode name="rule">
+            <properties>
+              <help>Destination NAT66 rule number</help>
+              <valueHelp>
+                <format>1-999999</format>
+                <description>Number for this rule</description>
+              </valueHelp>
+              <constraint>
+                <validator name="numeric" argument="--range 1-999999"/>
+              </constraint>
+              <constraintErrorMessage>NAT66 rule number must be between 1 and 999999</constraintErrorMessage>
+            </properties>
+            <children>
+              <leafNode name="description">
+                <properties>
+                  <help>Rule description</help>
+                </properties>
+              </leafNode>
+              <leafNode name="disable">
+                <properties>
+                  <help>Disable NAT66 rule</help>
+                  <valueless/>
+                </properties>
+              </leafNode>
+              <leafNode name="log">
+                <properties>
+                  <help>NAT66 rule logging</help>
+                  <valueless/>
+                </properties>
+              </leafNode>
+              <leafNode name="inbound-interface">
+                <properties>
+                  <help>Inbound interface of NAT66 traffic</help>
+                  <completionHelp>
+                    <list>any</list>
+                    <script>${vyos_completion_dir}/list_interfaces.py</script> 
+                  </completionHelp>
+                </properties>
+              </leafNode>
+              <node name="destination">
+                <properties>
+                  <help>IPv6 destination prefix options</help>
+                </properties>
+                <children>
+                  <leafNode name="address">
+                    <properties>
+                      <help>IPv6 address or prefix to be translated</help>
+                      <valueHelp>
+                        <format>ipv6</format>
+                        <description>IPv6 address</description>
+                      </valueHelp>
+                      <valueHelp>
+                        <format>ipv6net</format>
+                        <description>IPv6 prefix</description>
+                      </valueHelp>
+                      <constraint>
+                        <validator name="ipv6-address"/>
+                        <validator name="ipv6-prefix"/>
+                      </constraint>
+                    </properties>
+                  </leafNode>
+                </children>
+              </node>
+              <node name="translation">
+                <properties>
+                  <help>Translated IPv6 address options</help>
+                </properties>
+                <children>
+                  <leafNode name="address">
+                    <properties>
+                      <help>IPv6 address or prefix to translate to</help>
+                      <valueHelp>
+                        <format>ipv6</format>
+                        <description>IPv6 address</description>
+                      </valueHelp>
+                      <valueHelp>
+                        <format>ipv6net</format>
+                        <description>IPv6 prefix</description>
+                      </valueHelp>
+                      <constraint>
+                        <validator name="ipv6-address"/>
+                        <validator name="ipv6-prefix"/>
+                      </constraint>
+                    </properties>
+                  </leafNode>
+                </children>
+              </node>
+            </children>
+          </tagNode>
+        </children>
+      </node>
+    </children>
+  </node>
+</interfaceDefinition>
diff --git a/smoketest/scripts/cli/test_nat66.py b/smoketest/scripts/cli/test_nat66.py
new file mode 100755
index 000000000..ccc4196e0
--- /dev/null
+++ b/smoketest/scripts/cli/test_nat66.py
@@ -0,0 +1,156 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2020 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+import jmespath
+import json
+import unittest
+
+from vyos.configsession import ConfigSession
+from vyos.configsession import ConfigSessionError
+from vyos.util import cmd
+from vyos.util import dict_search
+
+base_path = ['nat66']
+src_path = base_path + ['source']
+dst_path = base_path + ['destination']
+
+class TestNAT66(unittest.TestCase):
+    def setUp(self):
+        # ensure we can also run this test on a live system - so lets clean
+        # out the current configuration :)
+        self.session = ConfigSession(os.getpid())
+        self.session.delete(base_path)
+
+    def tearDown(self):
+        self.session.delete(base_path)
+        self.session.commit()
+
+    def test_source_nat66(self):
+        source_prefix = 'fc00::/64'
+        translation_prefix = 'fc01::/64'
+        self.session.set(src_path + ['rule', '1', 'outbound-interface', 'eth1'])
+        self.session.set(src_path + ['rule', '1', 'source', 'prefix', source_prefix])
+        self.session.set(src_path + ['rule', '1', 'translation', 'prefix', translation_prefix])
+
+        # check validate() - outbound-interface must be defined
+        self.session.commit()
+
+        tmp = cmd('sudo nft -j list table ip6 nat')
+        data_json = jmespath.search('nftables[?rule].rule[?chain]', json.loads(tmp))
+
+        for idx in range(0, len(data_json)):
+            data = data_json[idx]
+
+            self.assertEqual(data['chain'], 'POSTROUTING')
+            self.assertEqual(data['family'], 'ip6')
+            self.assertEqual(data['table'], 'nat')
+
+            iface = dict_search('match.right', data['expr'][0])
+            address = dict_search('match.right.prefix.addr', data['expr'][2])
+            mask = dict_search('match.right.prefix.len', data['expr'][2])
+            translation_address = dict_search('snat.addr.prefix.addr', data['expr'][3])
+            translation_mask = dict_search('snat.addr.prefix.len', data['expr'][3])
+
+            self.assertEqual(iface, 'eth1')
+            # check for translation address
+            self.assertEqual(f'{translation_address}/{translation_mask}', translation_prefix)
+            self.assertEqual(f'{address}/{mask}', source_prefix)
+    
+    def test_destination_nat66(self):
+        destination_address = 'fc00::1'
+        translation_address = 'fc01::1'
+        self.session.set(dst_path + ['rule', '1', 'inbound-interface', 'eth1'])
+        self.session.set(dst_path + ['rule', '1', 'destination', 'address', destination_address])
+        self.session.set(dst_path + ['rule', '1', 'translation', 'address', translation_address])
+
+        # check validate() - outbound-interface must be defined
+        self.session.commit()
+
+        tmp = cmd('sudo nft -j list table ip6 nat')
+        data_json = jmespath.search('nftables[?rule].rule[?chain]', json.loads(tmp))
+
+        for idx in range(0, len(data_json)):
+            data = data_json[idx]
+
+            self.assertEqual(data['chain'], 'PREROUTING')
+            self.assertEqual(data['family'], 'ip6')
+            self.assertEqual(data['table'], 'nat')
+
+            iface = dict_search('match.right', data['expr'][0])
+            dnat_addr = dict_search('dnat.addr', data['expr'][3])
+
+            self.assertEqual(dnat_addr, translation_address)
+            self.assertEqual(iface, 'eth1')
+    
+    def test_destination_nat66_prefix(self):
+        destination_prefix = 'fc00::/64'
+        translation_prefix = 'fc01::/64'
+        self.session.set(dst_path + ['rule', '1', 'inbound-interface', 'eth1'])
+        self.session.set(dst_path + ['rule', '1', 'destination', 'address', destination_prefix])
+        self.session.set(dst_path + ['rule', '1', 'translation', 'address', translation_prefix])
+
+        # check validate() - outbound-interface must be defined
+        self.session.commit()
+
+        tmp = cmd('sudo nft -j list table ip6 nat')
+        data_json = jmespath.search('nftables[?rule].rule[?chain]', json.loads(tmp))
+
+        for idx in range(0, len(data_json)):
+            data = data_json[idx]
+
+            self.assertEqual(data['chain'], 'PREROUTING')
+            self.assertEqual(data['family'], 'ip6')
+            self.assertEqual(data['table'], 'nat')
+
+            iface = dict_search('match.right', data['expr'][0])
+            translation_address = dict_search('dnat.addr.prefix.addr', data['expr'][3])
+            translation_mask = dict_search('dnat.addr.prefix.len', data['expr'][3])
+
+            self.assertEqual(f'{translation_address}/{translation_mask}', translation_prefix)
+            self.assertEqual(iface, 'eth1')
+
+    def test_source_nat66_required_translation_prefix(self):
+        # T2813: Ensure translation address is specified
+        rule = '5'
+        source_prefix = 'fc00::/64'
+        translation_prefix = 'fc00:2::/64'
+        self.session.set(src_path + ['rule', rule, 'source', 'prefix', source_prefix])
+
+        # check validate() - outbound-interface must be defined
+        with self.assertRaises(ConfigSessionError):
+            self.session.commit()
+        self.session.set(src_path + ['rule', rule, 'outbound-interface', 'eth0'])
+
+        # check validate() - translation address not specified
+        with self.assertRaises(ConfigSessionError):
+            self.session.commit()
+
+        self.session.set(src_path + ['rule', rule, 'translation', 'prefix', translation_prefix])
+        self.session.commit()
+
+    def test_nat66_no_rules(self):
+        # T3206: deleting all rules but keep the direction 'destination' or
+        # 'source' resulteds in KeyError: 'rule'.
+        #
+        # Test that both 'nat destination' and 'nat source' nodes can exist
+        # without any rule
+        self.session.set(src_path)
+        self.session.set(dst_path)
+        self.session.commit()
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2)
diff --git a/src/conf_mode/nat66.py b/src/conf_mode/nat66.py
new file mode 100755
index 000000000..dc3cd550c
--- /dev/null
+++ b/src/conf_mode/nat66.py
@@ -0,0 +1,171 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2020 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import jmespath
+import json
+import os
+
+from sys import exit
+from netifaces import interfaces
+
+from vyos.config import Config
+from vyos.configdict import dict_merge
+from vyos.template import render
+from vyos.util import cmd
+from vyos.util import check_kmod
+from vyos.util import dict_search
+from vyos.template import is_ipv6
+from vyos.xml import defaults
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+k_mod = ['nft_nat', 'nft_chain_nat']
+
+iptables_nat_config = '/tmp/vyos-nat66-rules.nft'
+ndppd_config = '/run/ndppd/ndppd.conf'
+
+def get_handler(json, chain, target):
+    """ Get nftable rule handler number of given chain/target combination.
+    Handler is required when adding NAT66/Conntrack helper targets """
+    for x in json:
+        if x['chain'] != chain:
+            continue
+        if x['target'] != target:
+            continue
+        return x['handle']
+
+    return None
+
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
+    
+    base = ['nat66']
+    nat = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
+
+    # T2665: we must add the tagNode defaults individually until this is
+    # moved to the base class
+    for direction in ['source', 'destination']:
+        if direction in nat:
+            default_values = defaults(base + [direction, 'rule'])
+            if 'rule' in nat[direction]:
+                for rule in nat[direction]['rule']:
+                    nat[direction]['rule'][rule] = dict_merge(default_values,
+                        nat[direction]['rule'][rule])
+
+    # read in current nftable (once) for further processing
+    tmp = cmd('nft -j list table ip6 raw')
+    nftable_json = json.loads(tmp)
+
+    # condense the full JSON table into a list with only relevand informations
+    pattern = 'nftables[?rule].rule[?expr[].jump].{chain: chain, handle: handle, target: expr[].jump.target | [0]}'
+    condensed_json = jmespath.search(pattern, nftable_json)
+
+    if not conf.exists(base):
+        nat['helper_functions'] = 'remove'
+        nat['pre_ct_conntrack'] = get_handler(condensed_json, 'PREROUTING', 'NAT_CONNTRACK')
+        nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT','NAT_CONNTRACK')
+        nat['deleted'] = ''
+        return nat
+
+    # check if NAT66 connection tracking helpers need to be set up - this has to
+    # be done only once
+    if not get_handler(condensed_json, 'PREROUTING', 'NAT_CONNTRACK'):
+        nat['helper_functions'] = 'add'
+        
+        # Retrieve current table handler positions
+        nat['pre_ct_conntrack'] = get_handler(condensed_json, 'PREROUTING', 'VYATTA_CT_PREROUTING_HOOK')
+        nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT','VYATTA_CT_OUTPUT_HOOK')
+    else:
+        nat['helper_functions'] = 'has'
+
+    return nat
+
+def verify(nat):
+    if not nat or 'deleted' in nat:
+        # no need to verify the CLI as NAT66 is going to be deactivated
+        return None
+
+    if 'helper_functions' in nat and nat['helper_functions'] != 'has':
+        if not (nat['pre_ct_conntrack'] or nat['out_ct_conntrack']):
+            raise Exception('could not determine nftable ruleset handlers')
+    
+    if dict_search('source.rule', nat):
+        for rule, config in dict_search('source.rule', nat).items():
+            err_msg = f'Source NAT66 configuration error in rule {rule}:'
+            if 'outbound_interface' not in config:
+                raise ConfigError(f'{err_msg}\n' \
+                                  'outbound-interface not specified')
+            else:
+                if config['outbound_interface'] not in interfaces():
+                    print(f'WARNING: rule "{rule}" interface "{config["outbound_interface"]}" does not exist on this system')
+
+            prefix = dict_search('translation.prefix', config)
+            if prefix != None:
+                if not is_ipv6(prefix):
+                    raise ConfigError(f'Warning: IPv6 prefix {prefix} is not a valid address prefix')
+
+            prefix = dict_search('source.prefix', config)
+            if prefix != None:
+                if not is_ipv6(prefix):
+                    raise ConfigError(f'{err_msg} source-prefix not specified')
+
+    if dict_search('destination.rule', nat):
+        for rule, config in dict_search('destination.rule', nat).items():
+            err_msg = f'Destination NAT66 configuration error in rule {rule}:'
+
+            if 'inbound_interface' not in config:
+                raise ConfigError(f'{err_msg}\n' \
+                                  'inbound-interface not specified')
+            else:
+                if config['inbound_interface'] not in 'any' and config['inbound_interface'] not in interfaces():
+                    print(f'WARNING: rule "{rule}" interface "{config["inbound_interface"]}" does not exist on this system')
+
+    return None
+
+def generate(nat):
+    render(iptables_nat_config, 'firewall/nftables-nat66.tmpl', nat, permission=0o755)
+    render(ndppd_config, 'proxy-ndp/ndppd.conf.tmpl', nat, permission=0o755)
+    return None
+
+def apply(nat):
+    if not nat:
+        return None
+    cmd(f'{iptables_nat_config}')
+    if 'deleted' in nat or not dict_search('source.rule', nat):
+        cmd('systemctl stop ndppd')
+        if os.path.isfile(ndppd_config):
+            os.unlink(ndppd_config)
+    else:
+        cmd('systemctl restart ndppd')
+    if os.path.isfile(iptables_nat_config):
+        os.unlink(iptables_nat_config)
+
+    return None
+
+if __name__ == '__main__':
+    try:
+        check_kmod(k_mod)
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)
diff --git a/src/migration-scripts/nat66/0-to-1 b/src/migration-scripts/nat66/0-to-1
new file mode 100755
index 000000000..74d64c07b
--- /dev/null
+++ b/src/migration-scripts/nat66/0-to-1
@@ -0,0 +1,71 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2020 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from sys import argv,exit
+from vyos.configtree import ConfigTree
+
+if (len(argv) < 1):
+    print("Must specify file name!")
+    exit(1)
+
+file_name = argv[1]
+
+with open(file_name, 'r') as f:
+    config_file = f.read()
+
+config = ConfigTree(config_file)
+
+def merge_npt(config,base,rule):
+    merge_base = ['nat66','source','rule',rule]
+    # Configure migration functions
+    if config.exists(base + ['description']):
+        tmp = config.return_value(base + ['description'])
+        config.set(merge_base + ['description'],value=tmp)
+
+    if config.exists(base + ['disable']):
+        tmp = config.return_value(base + ['disable'])
+        config.set(merge_base + ['disable'],value=tmp)
+
+    if config.exists(base + ['outbound-interface']):
+        tmp = config.return_value(base + ['outbound-interface'])
+        config.set(merge_base + ['outbound-interface'],value=tmp)
+
+    if config.exists(base + ['source','prefix']):
+        tmp = config.return_value(base + ['source','prefix'])
+        config.set(merge_base + ['source','prefix'],value=tmp)
+
+    if config.exists(base + ['translation','prefix']):
+        tmp = config.return_value(base + ['translation','prefix'])
+        config.set(merge_base + ['translation','prefix'],value=tmp)
+
+if not config.exists(['nat', 'nptv6']):
+    # Nothing to do
+    exit(0)
+
+for rule in config.list_nodes(['nat', 'nptv6', 'rule']):
+    base = ['nat', 'nptv6', 'rule', rule]
+    # Merge 'nat nptv6' to 'nat66 source'
+    merge_npt(config,base,rule)
+
+# Delete the original NPT configuration
+config.delete(['nat','nptv6']);
+
+try:
+    with open(file_name, 'w') as f:
+        f.write(config.to_string())
+except OSError as e:
+    print("Failed to save the modified config: {}".format(e))
+    exit(1)
diff --git a/src/systemd/ndppd.service b/src/systemd/ndppd.service
new file mode 100644
index 000000000..5790d37f1
--- /dev/null
+++ b/src/systemd/ndppd.service
@@ -0,0 +1,15 @@
+[Unit]
+Description=NDP Proxy Daemon
+After=vyos-router.service
+ConditionPathExists=/run/ndppd/ndppd.conf
+StartLimitIntervalSec=0
+
+[Service]
+Type=forking
+ExecStart=/usr/sbin/ndppd -d -p /run/ndppd/ndppd.pid -c /run/ndppd/ndppd.conf
+PIDFile=/run/ndppd/ndppd.pid
+Restart=on-failure
+RestartSec=20
+
+[Install]
+WantedBy=multi-user.target