#!/usr/sbin/nft -f

{% macro nptv6_rule(rule,config, chain) %}
{% set comment  = '' %}
{% set base_log = '' %}
{% set src_prefix  = 'ip6 saddr ' ~ config.source.prefix if config.source.prefix is vyos_defined %}
{% set dest_address  = 'ip6 daddr ' ~ config.destination.address if config.destination.address is vyos_defined %}
{% if chain is vyos_defined('PREROUTING') %}
{%     set comment   = 'DST-NAT66-' ~ rule %}
{%     set base_log  = '[NAT66-DST-' ~ rule %}
{%     set interface = ' iifname "' ~ config.inbound_interface ~ '"' if config.inbound_interface is vyos_defined and config.inbound_interface is not vyos_defined('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.address is vyos_defined %}
{% elif chain is vyos_defined('POSTROUTING') %}
{%     set comment   = 'SRC-NAT66-' ~ rule %}
{%     set base_log  = '[NAT66-SRC-' ~ rule %}
{%     if config.translation.address is vyos_defined %}
{%         if config.translation.address is vyos_defined('masquerade') %}
{%             set trns_address = config.translation.address %}
{%         else %}
{%             if config.translation.address | is_ip_network %}
{#                 support 1:1 network translation #}
{%                 set snat_type = 'snat prefix to ' %}
{%             else   %}
{%                 set snat_type = 'snat to ' %}
{%             endif %}
{%             set trns_address = snat_type ~ config.translation.address %}
{%         endif %}
{%     endif   %}
{%     set interface = ' oifname "' ~ config.outbound_interface ~ '"' if config.outbound_interface is vyos_defined else '' %}
{% endif %}
{% if config.log is vyos_defined %}
{%     if config.translation.address is vyos_defined('masquerade') %}
{%         set log = base_log ~ '-MASQ]' %}
{%     else %}
{%         set log = base_log ~ ']' %}
{%     endif %}
{% 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 is vyos_defined %}
{%     set log_output = output ~ ' log prefix "' ~ log ~ '" comment "' ~ comment ~ '"' %}
{% endif %}
{% if src_prefix is vyos_defined %}
{%     set output = output ~ ' ' ~ src_prefix %}
{% endif %}
{% if dest_address is vyos_defined %}
{%     set output = output ~ ' ' ~ dest_address %}
{% endif %}
{% if trns_address is vyos_defined %}
{%     set output = output ~ ' ' ~ trns_address %}
{% endif %}
{% if comment is vyos_defined %}
{%     set output = output ~ ' comment "' ~ comment ~ '"' %}
{% endif %}
{{ log_output if log_output is vyos_defined }}
{{ output }}
{% endmacro %}

# Start with clean NAT table
flush table ip6 nat
{% if helper_functions is vyos_defined('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 is vyos_defined('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.rule is vyos_defined %}
{%     for rule, config in destination.rule.items() if config.disable is not vyos_defined %}
{{ nptv6_rule(rule, config, 'PREROUTING') }}
{%     endfor %}
{% endif %}
#
# Source NAT66 rules build up here
#
{% if source.rule is vyos_defined %}
{%     for rule, config in source.rule.items() if config.disable is not vyos_defined %}
{{ nptv6_rule(rule, config, 'POSTROUTING') }}
{%     endfor %}
{% endif %}