From c6bbe051574acf5ca1501e631d73ac06bdb17b30 Mon Sep 17 00:00:00 2001 From: sarthurdev <965089+sarthurdev@users.noreply.github.com> Date: Wed, 21 Sep 2022 02:05:30 +0200 Subject: nat: T4605: Refactor static NAT to use python module for parsing rules * Rename table to vyos_nat * Add static NAT smoketest --- data/templates/firewall/nftables-static-nat.j2 | 122 ++++--------------------- data/vyos-firewall-init.conf | 20 ---- python/vyos/nat.py | 62 +++++++++++++ python/vyos/template.py | 5 + smoketest/scripts/cli/test_nat.py | 4 +- src/conf_mode/nat.py | 4 +- 6 files changed, 91 insertions(+), 126 deletions(-) diff --git a/data/templates/firewall/nftables-static-nat.j2 b/data/templates/firewall/nftables-static-nat.j2 index d3c43858f..790c33ce9 100644 --- a/data/templates/firewall/nftables-static-nat.j2 +++ b/data/templates/firewall/nftables-static-nat.j2 @@ -1,115 +1,31 @@ #!/usr/sbin/nft -f -{% macro nat_rule(rule, config, chain) %} -{% set comment = '' %} -{% set base_log = '' %} - -{% if chain is vyos_defined('PREROUTING') %} -{% set comment = 'STATIC-NAT-' ~ rule %} -{% set base_log = '[NAT-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 vyos_defined %} -{# support 1:1 network translation #} -{% if config.translation.address | is_ip_network %} -{% set trns_addr = 'dnat ip prefix to ip daddr map { ' ~ config.destination.address ~ ' : ' ~ config.translation.address ~ ' }' %} -{# we can now clear out the dst_addr part as it's already covered in aboves map #} -{% else %} -{% set dst_addr = 'ip daddr ' ~ config.destination.address if config.destination.address is vyos_defined %} -{% set trns_addr = 'dnat to ' ~ config.translation.address %} -{% endif %} -{% endif %} -{% elif chain is vyos_defined('POSTROUTING') %} -{% set comment = 'STATIC-NAT-' ~ rule %} -{% set base_log = '[NAT-SRC-' ~ rule %} -{% set interface = ' oifname "' ~ 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 vyos_defined %} -{# support 1:1 network translation #} -{% if config.translation.address | is_ip_network %} -{% set trns_addr = 'snat ip prefix to ip saddr map { ' ~ config.translation.address ~ ' : ' ~ config.destination.address ~ ' }' %} -{# we can now clear out the src_addr part as it's already covered in aboves map #} -{% else %} -{% set src_addr = 'ip saddr ' ~ config.translation.address if config.translation.address is vyos_defined %} -{% set trns_addr = 'snat to ' ~ config.destination.address %} -{% endif %} -{% endif %} -{% endif %} - -{% if config.exclude is vyos_defined %} -{# rule has been marked as 'exclude' thus we simply return here #} -{% set trns_addr = 'return' %} -{% set trns_port = '' %} -{% endif %} - -{% if config.translation.options is vyos_defined %} -{% if config.translation.options.address_mapping is vyos_defined('persistent') %} -{% set trns_opts_addr = 'persistent' %} -{% endif %} -{% if config.translation.options.port_mapping is vyos_defined('random') %} -{% set trns_opts_port = 'random' %} -{% elif config.translation.options.port_mapping is vyos_defined('fully-random') %} -{% set trns_opts_port = 'fully-random' %} -{% endif %} -{% endif %} - -{% if trns_opts_addr is vyos_defined and trns_opts_port is vyos_defined %} -{% set trns_opts = trns_opts_addr ~ ',' ~ trns_opts_port %} -{% elif trns_opts_addr is vyos_defined %} -{% set trns_opts = trns_opts_addr %} -{% elif trns_opts_port is vyos_defined %} -{% set trns_opts = trns_opts_port %} -{% endif %} - -{% set output = 'add rule ip vyos_static_nat ' ~ chain ~ interface %} - -{% if dst_addr is vyos_defined %} -{% set output = output ~ ' ' ~ dst_addr %} +{% if first_install is not vyos_defined %} +delete table ip vyos_static_nat {% endif %} -{% if src_addr is vyos_defined %} -{% set output = output ~ ' ' ~ src_addr %} -{% 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 is vyos_defined %} -{% set log_output = output ~ ' log prefix "' ~ log ~ '" comment "' ~ comment ~ '"' %} -{% endif %} -{% if trns_addr is vyos_defined %} -{% set output = output ~ ' ' ~ trns_addr %} -{% endif %} - -{% if trns_opts is vyos_defined %} -{% set output = output ~ ' ' ~ trns_opts %} -{% 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 STATIC NAT chains -flush chain ip vyos_static_nat PREROUTING -flush chain ip vyos_static_nat POSTROUTING +table ip vyos_static_nat { + # + # Destination NAT rules build up here + # -{# NAT if enabled - add targets to nftables #} - -# -# Destination NAT rules build up here -# -add rule ip vyos_static_nat PREROUTING counter jump VYOS_PRE_DNAT_HOOK + chain PREROUTING { + type nat hook prerouting priority -100; policy accept; {% if static.rule is vyos_defined %} {% for rule, config in static.rule.items() if config.disable is not vyos_defined %} -{{ nat_rule(rule, config, 'PREROUTING') }} + {{ config | nat_static_rule(rule, 'destination') }} {% endfor %} {% endif %} -# -# Source NAT rules build up here -# -add rule ip vyos_static_nat POSTROUTING counter jump VYOS_PRE_SNAT_HOOK + } + + # + # Source NAT rules build up here + # + chain POSTROUTING { + type nat hook postrouting priority 100; policy accept; {% if static.rule is vyos_defined %} {% for rule, config in static.rule.items() if config.disable is not vyos_defined %} -{{ nat_rule(rule, config, 'POSTROUTING') }} + {{ config | nat_static_rule(rule, 'source') }} {% endfor %} {% endif %} + } +} diff --git a/data/vyos-firewall-init.conf b/data/vyos-firewall-init.conf index 3a0e1ee48..11a5bc7bf 100644 --- a/data/vyos-firewall-init.conf +++ b/data/vyos-firewall-init.conf @@ -1,25 +1,5 @@ #!/usr/sbin/nft -f -table ip vyos_static_nat { - chain PREROUTING { - type nat hook prerouting priority -100; policy accept; - counter jump VYOS_PRE_DNAT_HOOK - } - - chain POSTROUTING { - type nat hook postrouting priority 100; policy accept; - counter jump VYOS_PRE_SNAT_HOOK - } - - chain VYOS_PRE_DNAT_HOOK { - return - } - - chain VYOS_PRE_SNAT_HOOK { - return - } -} - # Required by wanloadbalance table ip nat { chain VYOS_PRE_SNAT_HOOK { diff --git a/python/vyos/nat.py b/python/vyos/nat.py index 44dd65372..31bbdc386 100644 --- a/python/vyos/nat.py +++ b/python/vyos/nat.py @@ -124,3 +124,65 @@ def parse_nat_rule(rule_conf, rule_id, nat_type, ipv6=False): output.append(f'comment "{log_prefix}"') return " ".join(output) + +def parse_nat_static_rule(rule_conf, rule_id, nat_type): + output = [] + log_prefix = ('STATIC-DST' if nat_type == 'destination' else 'STATIC-SRC') + f'-NAT-{rule_id}' + log_suffix = '' + + ignore_type_addr = False + translation_str = '' + + if 'inbound_interface' in rule_conf: + ifname = rule_conf['inbound_interface'] + ifprefix = 'i' if nat_type == 'destination' else 'o' + if ifname != 'any': + output.append(f'{ifprefix}ifname "{ifname}"') + + if 'exclude' in rule_conf: + translation_str = 'return' + log_suffix = '-EXCL' + elif 'translation' in rule_conf: + translation_prefix = nat_type[:1] + translation_output = [f'{translation_prefix}nat'] + addr = dict_search_args(rule_conf, 'translation', 'address') + map_addr = dict_search_args(rule_conf, 'destination', 'address') + + if nat_type == 'source': + addr, map_addr = map_addr, addr # Swap + + if addr and is_ip_network(addr): + translation_output.append(f'ip prefix to ip {translation_prefix}addr map {{ {map_addr} : {addr} }}') + ignore_type_addr = True + elif addr: + translation_output.append(f'to {addr}') + + options = [] + addr_mapping = dict_search_args(rule_conf, 'translation', 'options', 'address_mapping') + port_mapping = dict_search_args(rule_conf, 'translation', 'options', 'port_mapping') + if addr_mapping == 'persistent': + options.append('persistent') + if port_mapping and port_mapping != 'none': + options.append(port_mapping) + + if options: + translation_output.append(",".join(options)) + + translation_str = " ".join(translation_output) + + prefix = nat_type[:1] + addr = dict_search_args(rule_conf, 'translation' if nat_type == 'source' else nat_type, 'address') + if addr and not ignore_type_addr: + output.append(f'ip {prefix}addr {addr}') + + output.append('counter') + + if translation_str: + output.append(translation_str) + + if 'log' in rule_conf: + output.append(f'log prefix "[{log_prefix}{log_suffix}]"') + + output.append(f'comment "{log_prefix}"') + + return " ".join(output) diff --git a/python/vyos/template.py b/python/vyos/template.py index d9ff98d2e..0870a0523 100644 --- a/python/vyos/template.py +++ b/python/vyos/template.py @@ -621,6 +621,11 @@ def nat_rule(rule_conf, rule_id, nat_type, ipv6=False): from vyos.nat import parse_nat_rule return parse_nat_rule(rule_conf, rule_id, nat_type, ipv6) +@register_filter('nat_static_rule') +def nat_static_rule(rule_conf, rule_id, nat_type): + from vyos.nat import parse_nat_static_rule + return parse_nat_static_rule(rule_conf, rule_id, nat_type) + @register_filter('range_to_regex') def range_to_regex(num_range): from vyos.range_regex import range_to_regex diff --git a/smoketest/scripts/cli/test_nat.py b/smoketest/scripts/cli/test_nat.py index 5863409be..f824838c0 100755 --- a/smoketest/scripts/cli/test_nat.py +++ b/smoketest/scripts/cli/test_nat.py @@ -184,10 +184,10 @@ class TestNAT(VyOSUnitTestSHIM.TestCase): [f'iifname "{ifname}"', f'ip daddr {dst_addr_1}', f'dnat to {translate_addr_1}'], [f'oifname "{ifname}"', f'ip saddr {translate_addr_1}', f'snat to {dst_addr_1}'], [f'iifname "{ifname}"', f'dnat ip prefix to ip daddr map {{ {dst_addr_2} : {translate_addr_2} }}'], - [f'oifname "{ifname}"', f'snat ip prefix to ip daddr map {{ {translate_addr_2} : {dst_addr_2} }}'] + [f'oifname "{ifname}"', f'snat ip prefix to ip saddr map {{ {translate_addr_2} : {dst_addr_2} }}'] ] - self.verify_nftables(nftables_search, 'ip vyos_nat') + self.verify_nftables(nftables_search, 'ip vyos_static_nat') if __name__ == '__main__': unittest.main(verbosity=2) diff --git a/src/conf_mode/nat.py b/src/conf_mode/nat.py index 3f52d7c1f..8b1a5a720 100755 --- a/src/conf_mode/nat.py +++ b/src/conf_mode/nat.py @@ -194,7 +194,9 @@ def generate(nat): if tmp > 0: raise ConfigError('Configuration file errors encountered!') - tmp = run(f'nft -c -f {nftables_nat_config}') + tmp = run(f'nft -c -f {nftables_static_nat_conf}') + if tmp > 0: + raise ConfigError('Configuration file errors encountered!') return None -- cgit v1.2.3