nat: T3092: migrate to get_config_dict()

The NAT system consists out of nested tag nodes which makes manual parsing very
hard. This is a perfect candidate for migrating this to get_config_dict() as
there is already a smoketest in place.

In addition this should make it easier to add features like static nat/hairpin.

1 files changed, 62 insertions, 80 deletions

diff --git a/data/templates/firewall/nftables-nat.tmpl b/data/templates/firewall/nftables-nat.tmpl
index eabad56f2..8769c2384 100644
--- a/data/templates/firewall/nftables-nat.tmpl
+++ b/data/templates/firewall/nftables-nat.tmpl
@@ -1,161 +1,143 @@
 #!/usr/sbin/nft -f
 
-# Start with clean NAT table
-flush table nat
-
-{% if helper_functions == 'remove' %}
-{# NAT if going to be disabled - remove rules and targets from nftables #}
-
-{%   set base_command = "delete rule ip raw" %}
-{{ base_command }} PREROUTING handle {{ pre_ct_ignore }}
-{{ base_command }} OUTPUT     handle {{ out_ct_ignore }}
-{{ base_command }} PREROUTING handle {{ pre_ct_conntrack }}
-{{ base_command }} OUTPUT     handle {{ out_ct_conntrack }}
-
-delete chain ip raw NAT_CONNTRACK
-
-{% elif helper_functions == 'add' %}
-{# NAT if enabled - add targets to nftables #}
-add chain ip raw NAT_CONNTRACK
-add rule ip raw NAT_CONNTRACK counter accept
-
-{%   set base_command = "add rule ip raw" %}
-
-{{ base_command }} PREROUTING position {{ pre_ct_ignore }}    counter jump VYATTA_CT_HELPER
-{{ base_command }} OUTPUT     position {{ out_ct_ignore }}    counter jump VYATTA_CT_HELPER
-{{ base_command }} PREROUTING position {{ pre_ct_conntrack }} counter jump NAT_CONNTRACK
-{{ base_command }} OUTPUT     position {{ out_ct_conntrack }} counter jump NAT_CONNTRACK
-{% endif %}
-
-{% macro nat_rule(rule, chain) %}
+{% macro nat_rule(rule, config, chain) %}
 {%   set comment  = "" %}
 {%   set base_log = "" %}
-
-{%   set src_addr  = "ip saddr " + rule.source_address if rule.source_address %}
-{%   set dst_addr  = "ip daddr " + rule.dest_address if rule.dest_address %}
-
+{%   set src_addr  = "ip saddr " + config.source.address if config.source is defined and config.source.address is defined and config.source.address is not none %}
+{%   set dst_addr  = "ip daddr " + config.destination.address if config.destination is defined and config.destination.address is defined and config.destination.address is not none %}
 {#   negated port groups need special treatment, move != in front of { } group #}
-{%   if rule.source_port.startswith('!=') %}
-{%     set src_port  = "sport != { " + rule.source_port.replace('!=','') +" }" if rule.source_port %}
+{%   if config.source is defined and config.source.port is defined and config.source.port is not none and config.source.port.startswith('!=') %}
+{%     set src_port  = "sport != { " + config.source.port.replace('!=','') +" }" %}
 {%   else %}
-{%     set src_port  = "sport { " + rule.source_port +" }" if rule.source_port %}
+{%     set src_port  = "sport { " + config.source.port +" }" if config.source is defined and config.source.port is defined and config.source.port is not none %}
 {%   endif %}
-
 {#   negated port groups need special treatment, move != in front of { } group #}
-{%   if rule.dest_port.startswith('!=') %}
-{%     set dst_port  = "dport != { " + rule.dest_port.replace('!=','') +" }" if rule.dest_port %}
+{%   if config.destination is defined and config.destination.port is defined and config.destination.port is not none and config.destination.port.startswith('!=') %}
+{%     set dst_port  = "dport != { " + config.destination.port.replace('!=','') +" }" %}
 {%   else %}
-{%     set dst_port  = "dport { " + rule.dest_port +" }" if rule.dest_port %}
+{%     set dst_port  = "dport { " + config.destination.port +" }" if config.destination is defined and config.destination.port is defined and config.destination.port is not none %}
 {%   endif %}
-
 {%   if chain == "PREROUTING" %}
-{%     set comment   = "DST-NAT-" + rule.number %}
-{%     set base_log  = "[NAT-DST-" + rule.number %}
-{%     set interface = " iifname \"" + rule.interface_in + "\"" if rule.interface_in is defined and rule.interface_in != 'any' else '' %}
-{%     set trns_addr = "dnat to " + rule.translation_address %}
-
+{%     set comment   = "DST-NAT-" + rule %}
+{%     set base_log  = "[NAT-DST-" + rule %}
+{%     set interface = " iifname \"" + config.inbound_interface + "\"" if config.inbound_interface is defined and config.inbound_interface != 'any' else '' %}
+{%     set trns_addr = "dnat to " + 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 comment   = "SRC-NAT-" + rule.number %}
-{%     set base_log  = "[NAT-SRC-" + rule.number %}
-{%     set interface = " oifname \"" + rule.interface_out + "\"" if rule.interface_out is defined and rule.interface_out != 'any' else '' %}
-{%     if rule.translation_address == 'masquerade' %}
-{%       set trns_addr = rule.translation_address %}
-{%       if rule.translation_port %}
+{%     set comment   = "SRC-NAT-" + rule %}
+{%     set base_log  = "[NAT-SRC-" + rule %}
+{%     set interface = " oifname \"" + config.outbound_interface + "\"" if config.outbound_interface is defined and config.outbound_interface != 'any' else '' %}
+{%     if config.translation is defined and config.translation.address is defined and config.translation.address == 'masquerade' %}
+{%       set trns_addr = config.translation.address %}
+{%       if config.translation.port is defined and config.translation.port is not none %}
 {%         set trns_addr = trns_addr + " to " %}
 {%       endif %}
 {%     else %}
-{%       set trns_addr = "snat to " + rule.translation_address %}
+{%       set trns_addr = "snat to " + config.translation.address if config.translation is defined and config.translation.address is defined and config.translation.address is not none %}
 {%     endif %}
 {%   endif %}
-{%   set trns_port = ":" + rule.translation_port if rule.translation_port %}
-
-{%   if rule.protocol == "tcp_udp" %}
+{%   set trns_port = ":" + config.translation.port if config.translation is defined and config.translation.port is defined and config.translation.port is not none %}
+{#   protocol has a default value thus it is always present #}
+{%   if config.protocol == "tcp_udp" %}
 {%     set protocol  = "tcp" %}
 {%     set comment   = comment + " tcp_udp" %}
 {%   else %}
-{%     set protocol  = rule.protocol %}
+{%     set protocol  = config.protocol %}
 {%   endif %}
-
-{%   if rule.log %}
-{%     if rule.exclude %}
+{%   if config.log is defined %}
+{%     if config.exclude is defined %}
 {%       set log = base_log + "-EXCL]" %}
-{%     elif rule.translation_address == 'masquerade' %}
+{%     elif config.translation is defined and config.translation.address is defined and config.translation.address == 'masquerade' %}
 {%       set log = base_log + "-MASQ]" %}
 {%     else %}
 {%       set log = base_log + "]" %}
 {%     endif %}
 {%   endif %}
-
-{%   if rule.exclude %}
+{%   if config.exclude is defined %}
 {#     rule has been marked as "exclude" thus we simply return here #}
 {%     set trns_addr = "return" %}
 {%     set trns_port = "" %}
 {%   endif %}
-
 {%   set output = "add rule ip nat " + chain + interface %}
-
 {%   if protocol != "all" %}
 {%     set output = output + " ip protocol " + protocol %}
 {%   endif %}
-
 {%   if src_addr %}
 {%     set output = output + " " + src_addr %}
 {%   endif %}
 {%   if src_port %}
 {%     set output = output + " " + protocol + " " + src_port %}
 {%   endif %}
-
 {%   if dst_addr %}
 {%     set output = output + " " + dst_addr %}
 {%   endif %}
 {%   if dst_port %}
 {%     set output = output + " " + protocol + " " + dst_port %}
 {%   endif %}
-
 {#   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 trns_addr %}
 {%     set output = output + " " + trns_addr %}
 {%   endif %}
-
 {%   if trns_port %}
 {#     Do not add a whitespace here, translation port must be directly added after IP address #}
 {#     e.g. 192.0.2.10:3389                                                                   #}
 {%     set output = output + trns_port %}
 {%   endif %}
-
 {%   if comment %}
 {%     set output = output + " comment \"" + comment + "\"" %}
 {%   endif %}
-
 {{ log_output if log_output }}
 {{ output }}
-
 {#   Special handling if protocol is tcp_udp, we must repeat the entire rule with udp as protocol #}
-{%   if rule.protocol == "tcp_udp" %}
+{%   if config.protocol == "tcp_udp" %}
 {#     Beware of trailing whitespace, without it the comment tcp_udp will be changed to udp_udp   #}
 {{ log_output | replace("tcp ", "udp ") if log_output }}
 {{ output | replace("tcp ", "udp ") }}
 {%   endif %}
 {% endmacro %}
 
+# Start with clean NAT table
+flush table nat
+{% if helper_functions == 'remove' %}
+{# NAT if going to be disabled - remove rules and targets from nftables #}
+{%   set base_command = "delete rule ip raw" %}
+{{ base_command }} PREROUTING handle {{ pre_ct_ignore }}
+{{ base_command }} OUTPUT     handle {{ out_ct_ignore }}
+{{ base_command }} PREROUTING handle {{ pre_ct_conntrack }}
+{{ base_command }} OUTPUT     handle {{ out_ct_conntrack }}
+
+delete chain ip raw NAT_CONNTRACK
+
+{% elif helper_functions == 'add' %}
+{# NAT if enabled - add targets to nftables #}
+add chain ip raw NAT_CONNTRACK
+add rule ip raw NAT_CONNTRACK counter accept
+{%   set base_command = "add rule ip raw" %}
+{{ base_command }} PREROUTING position {{ pre_ct_ignore }}    counter jump VYATTA_CT_HELPER
+{{ base_command }} OUTPUT     position {{ out_ct_ignore }}    counter jump VYATTA_CT_HELPER
+{{ base_command }} PREROUTING position {{ pre_ct_conntrack }} counter jump NAT_CONNTRACK
+{{ base_command }} OUTPUT     position {{ out_ct_conntrack }} counter jump NAT_CONNTRACK
+{% endif %}
+
 #
 # Destination NAT rules build up here
 #
-{% for rule in destination if not rule.disabled %}
-{{ nat_rule(rule, 'PREROUTING') }}
-{% endfor %}
+{% 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 %}
+{{ nat_rule(rule, config, 'PREROUTING') }}
+{%   endfor %}
+{% endif %}
 
 #
 # Source NAT rules build up here
 #
-{% for rule in source if not rule.disabled %}
-{{ nat_rule(rule, 'POSTROUTING') }}
-{% endfor %}
+{% 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 %}
+{{ nat_rule(rule, config, 'POSTROUTING') }}
+{%   endfor %}
+{% endif %}