T2898: add ndp-proxy service

VyOS CLI command
  set service ndp-proxy interface eth0 prefix 2001:db8::/64 mode 'static'

Will generate the following NDP proxy configuration

  $ cat /run/ndppd/ndppd.conf
  # autogenerated by service_ndp-proxy.py

  # This tells 'ndppd' how often to reload the route file /proc/net/ipv6_route
  route-ttl 30000

  # This sets up a listener, that will listen for any Neighbor Solicitation
  # messages, and respond to them according to a set of rules
  proxy eth0 {
      # Turn on or off the router flag for Neighbor Advertisements
      router no
      # Control how long to wait for a Neighbor Advertisment message before invalidating the entry (milliseconds)
      timeout 500
      # Control how long a valid or invalid entry remains in the cache (milliseconds)
      ttl 30000

      # This is a rule that the target address is to match against. If no netmask
      # is provided, /128 is assumed. You may have several rule sections, and the
      # addresses may or may not overlap.
      rule 2001:db8::/64 {
          static
      }
  }

1 files changed, 31 insertions, 40 deletions

diff --git a/data/templates/ndppd/ndppd.conf.j2 b/data/templates/ndppd/ndppd.conf.j2
index 1297f36be..6369dbdeb 100644
--- a/data/templates/ndppd/ndppd.conf.j2
+++ b/data/templates/ndppd/ndppd.conf.j2
@@ -1,44 +1,35 @@
-########################################################
-#
-# 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
-#
-########################################################
+# autogenerated by service_ndp-proxy.py
 
-{% set global = namespace(ndppd_interfaces = [],ndppd_prefixs = []) %}
-{% if source.rule is vyos_defined %}
-{%     for rule, config in source.rule.items() if config.disable is not defined %}
-{%         if config.outbound_interface.name is vyos_defined %}
-{%             if config.outbound_interface.name not in global.ndppd_interfaces %}
-{%                 set global.ndppd_interfaces = global.ndppd_interfaces + [config.outbound_interface.name] %}
-{%             endif   %}
-{%             if config.translation.address is vyos_defined and config.translation.address | is_ip_network %}
-{%                 set global.ndppd_prefixs = global.ndppd_prefixs + [{'interface':config.outbound_interface.name,'rule':config.translation.address}] %}
-{%             endif %}
-{%         endif %}
-{%     endfor %}
-{% endif %}
+# This tells 'ndppd' how often to reload the route file /proc/net/ipv6_route
+route-ttl {{ route_refresh }}
+
+{% if interface is vyos_defined %}
+# This sets up a listener, that will listen for any Neighbor Solicitation
+# messages, and respond to them according to a set of rules
+{%     for iface, iface_config in interface.items() if iface_config.disable is not vyos_defined %}
+proxy {{ iface }} {
+    # Turn on or off the router flag for Neighbor Advertisements
+    router {{ 'yes' if iface_config.enable_router_bit is vyos_defined else 'no' }}
+    # Control how long to wait for a Neighbor Advertisment message before invalidating the entry (milliseconds)
+    timeout {{ iface_config.timeout }}
+    # Control how long a valid or invalid entry remains in the cache (milliseconds)
+    ttl {{ iface_config.ttl }}
 
-{% 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
+{%         if iface_config.prefix is vyos_defined %}
+    # This is a rule that the target address is to match against. If no netmask
+    # is provided, /128 is assumed. You may have several rule sections, and the
+    # addresses may or may not overlap.
+{%             for prefix, prefix_config in iface_config.prefix.items() if prefix_config.disable is not vyos_defined %}
+    rule {{ prefix }} {
+{%                 if prefix_config.mode is vyos_defined('interface') %}
+        iface {{ prefix_config.interface }}
+{%                 else %}
+        {{ prefix_config.mode }}
+{%                 endif %}
     }
-{%         endif  %}
-{%     endfor   %}
+{%             endfor %}
+{%         endif %}
 }
-{% endfor %}
+
+{%     endfor %}
+{% endif %}