diff options
| -rw-r--r-- | data/templates/firewall/nftables-nat.tmpl | 142 | ||||
| -rw-r--r-- | interface-definitions/include/nat-rule.xml.i | 1 | ||||
| -rwxr-xr-x | src/conf_mode/nat.py | 233 |
3 files changed, 136 insertions, 240 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 %} diff --git a/interface-definitions/include/nat-rule.xml.i b/interface-definitions/include/nat-rule.xml.i index f91834ae0..e70cfd796 100644 --- a/interface-definitions/include/nat-rule.xml.i +++ b/interface-definitions/include/nat-rule.xml.i @@ -290,6 +290,7 @@ <validator name="ip-protocol"/> </constraint> </properties> + <defaultValue>all</defaultValue> </leafNode> <node name="source"> <properties> diff --git a/src/conf_mode/nat.py b/src/conf_mode/nat.py index b467f3d74..f5c023b81 100755 --- a/src/conf_mode/nat.py +++ b/src/conf_mode/nat.py @@ -18,18 +18,19 @@ import jmespath import json import os -from copy import deepcopy from distutils.version import LooseVersion from platform import release as kernel_version 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 call from vyos.util import cmd from vyos.util import check_kmod +from vyos.util import dict_search from vyos.validate import is_addr_assigned +from vyos.xml import defaults from vyos import ConfigError from vyos import airbag @@ -40,17 +41,6 @@ if LooseVersion(kernel_version()) > LooseVersion('5.1'): else: k_mod = ['nft_nat', 'nft_chain_nat_ipv4'] -default_config_data = { - 'deleted': False, - 'destination': [], - 'helper_functions': None, - 'pre_ct_helper': '', - 'pre_ct_conntrack': '', - 'out_ct_helper': '', - 'out_ct_conntrack': '', - 'source': [] -} - iptables_nat_config = '/tmp/vyos-nat-rules.nft' def get_handler(json, chain, target): @@ -66,114 +56,43 @@ def get_handler(json, chain, target): return None -def verify_rule(rule, err_msg): +def verify_rule(config, err_msg): """ Common verify steps used for both source and destination NAT """ - if rule['translation_port'] or rule['dest_port'] or rule['source_port']: - if rule['protocol'] not in ['tcp', 'udp', 'tcp_udp']: - proto = rule['protocol'] - raise ConfigError(f'{err_msg} ports can only be specified when protocol is "tcp", "udp" or "tcp_udp" (currently "{proto}")') - if '/' in rule['translation_address']: + if (dict_search('translation.port', config) != None or + dict_search('destination.port', config) != None or + dict_search('source.port', config)): + + if config['protocol'] not in ['tcp', 'udp', 'tcp_udp']: + raise ConfigError(f'{err_msg}\n' \ + 'ports can only be specified when protocol is '\ + 'either tcp, udp or tcp_udp!') + + if '/' in (dict_search('translation.address', config) or []): raise ConfigError(f'{err_msg}\n' \ 'Cannot use ports with an IPv4net type translation address as it\n' \ 'statically maps a whole network of addresses onto another\n' \ 'network of addresses') - -def parse_configuration(conf, source_dest): - """ Common wrapper to read in both NAT source and destination CLI """ - ruleset = [] - base_level = ['nat', source_dest] - conf.set_level(base_level) - for number in conf.list_nodes(['rule']): - rule = { - 'description': '', - 'dest_address': '', - 'dest_port': '', - 'disabled': False, - 'exclude': False, - 'interface_in': '', - 'interface_out': '', - 'log': False, - 'protocol': 'all', - 'number': number, - 'source_address': '', - 'source_prefix': '', - 'source_port': '', - 'translation_address': '', - 'translation_prefix': '', - 'translation_port': '' - } - conf.set_level(base_level + ['rule', number]) - - if conf.exists(['description']): - rule['description'] = conf.return_value(['description']) - - if conf.exists(['destination', 'address']): - tmp = conf.return_value(['destination', 'address']) - if tmp.startswith('!'): - tmp = tmp.replace('!', '!=') - rule['dest_address'] = tmp - - if conf.exists(['destination', 'port']): - tmp = conf.return_value(['destination', 'port']) - if tmp.startswith('!'): - tmp = tmp.replace('!', '!=') - rule['dest_port'] = tmp - - if conf.exists(['disable']): - rule['disabled'] = True - - if conf.exists(['exclude']): - rule['exclude'] = True - - if conf.exists(['inbound-interface']): - rule['interface_in'] = conf.return_value(['inbound-interface']) - - if conf.exists(['outbound-interface']): - rule['interface_out'] = conf.return_value(['outbound-interface']) - - if conf.exists(['log']): - rule['log'] = True - - if conf.exists(['protocol']): - rule['protocol'] = conf.return_value(['protocol']) - - if conf.exists(['source', 'address']): - tmp = conf.return_value(['source', 'address']) - if tmp.startswith('!'): - tmp = tmp.replace('!', '!=') - rule['source_address'] = tmp - - if conf.exists(['source', 'prefix']): - rule['source_prefix'] = conf.return_value(['source', 'prefix']) - - if conf.exists(['source', 'port']): - tmp = conf.return_value(['source', 'port']) - if tmp.startswith('!'): - tmp = tmp.replace('!', '!=') - rule['source_port'] = tmp - - if conf.exists(['translation', 'address']): - rule['translation_address'] = conf.return_value(['translation', 'address']) - - if conf.exists(['translation', 'prefix']): - rule['translation_prefix'] = conf.return_value(['translation', 'prefix']) - - if conf.exists(['translation', 'port']): - rule['translation_port'] = conf.return_value(['translation', 'port']) - - ruleset.append(rule) - - return ruleset - def get_config(config=None): - nat = deepcopy(default_config_data) if config: conf = config else: conf = Config() + base = ['nat'] + 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']) + 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 raw') nftable_json = json.loads(tmp) @@ -182,7 +101,7 @@ def get_config(config=None): 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(['nat']): + if not conf.exists(base): nat['helper_functions'] = 'remove' # Retrieve current table handler positions @@ -190,9 +109,7 @@ def get_config(config=None): nat['pre_ct_conntrack'] = get_handler(condensed_json, 'PREROUTING', 'NAT_CONNTRACK') nat['out_ct_ignore'] = get_handler(condensed_json, 'OUTPUT', 'VYATTA_CT_HELPER') nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT', 'NAT_CONNTRACK') - - nat['deleted'] = True - + nat['deleted'] = '' return nat # check if NAT connection tracking helpers need to be set up - this has to @@ -206,19 +123,10 @@ def get_config(config=None): nat['out_ct_ignore'] = get_handler(condensed_json, 'OUTPUT', 'VYATTA_CT_IGNORE') nat['out_ct_conntrack'] = get_handler(condensed_json, 'OUTPUT', 'VYATTA_CT_OUTPUT_HOOK') - # set config level for parsing in NAT configuration - conf.set_level(['nat']) - - # use a common wrapper function to read in the source / destination - # tree from the config - thus we do not need to replicate almost the - # same code :-) - for tgt in ['source', 'destination', 'nptv6']: - nat[tgt] = parse_configuration(conf, tgt) - return nat def verify(nat): - if nat['deleted']: + if not nat or 'deleted' in nat: # no need to verify the CLI as NAT is going to be deactivated return None @@ -226,44 +134,49 @@ def verify(nat): if not (nat['pre_ct_ignore'] or nat['pre_ct_conntrack'] or nat['out_ct_ignore'] or nat['out_ct_conntrack']): raise Exception('could not determine nftable ruleset handlers') - for rule in nat['source']: - interface = rule['interface_out'] - err_msg = f'Source NAT configuration error in rule "{rule["number"]}":' - - if interface and interface not in 'any' and interface not in interfaces(): - print(f'Warning: rule "{rule["number"]}" interface "{interface}" does not exist on this system') - - if not rule['interface_out']: - raise ConfigError(f'{err_msg} outbound-interface not specified') - - if rule['translation_address']: - addr = rule['translation_address'] - if addr != 'masquerade': - for ip in addr.split('-'): - if not is_addr_assigned(ip): - print(f'Warning: IP address {ip} does not exist on the system!') - - elif not rule['exclude']: - raise ConfigError(f'{err_msg} translation address not specified') - - # common rule verification - verify_rule(rule, err_msg) - - for rule in nat['destination']: - interface = rule['interface_in'] - err_msg = f'Destination NAT configuration error in rule "{rule["number"]}":' - - if interface and interface not in 'any' and interface not in interfaces(): - print(f'Warning: rule "{rule["number"]}" interface "{interface}" does not exist on this system') - - if not rule['interface_in']: - raise ConfigError(f'{err_msg} inbound-interface not specified') - - if not rule['translation_address'] and not rule['exclude']: - raise ConfigError(f'{err_msg} translation address not specified') - - # common rule verification - verify_rule(rule, err_msg) + if dict_search('source.rule', nat): + for rule, config in dict_search('source.rule', nat).items(): + err_msg = f'Source NAT 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 'any' and config['outbound_interface'] not in interfaces(): + print(f'WARNING: rule "{rule}" interface "{config["outbound_interface"]}" does not exist on this system') + + + addr = dict_search('translation.address', config) + if addr != None: + if addr != 'masquerade': + for ip in addr.split('-'): + if not is_addr_assigned(ip): + print(f'WARNING: IP address {ip} does not exist on the system!') + elif 'exclude' not in config: + raise ConfigError(f'{err_msg}\n' \ + 'translation address not specified') + + # common rule verification + verify_rule(config, err_msg) + + + if dict_search('destination.rule', nat): + for rule, config in dict_search('destination.rule', nat).items(): + err_msg = f'Destination NAT 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') + + + if dict_search('translation.address', config) == None and 'exclude' not in config: + raise ConfigError(f'{err_msg}\n' \ + 'translation address not specified') + + # common rule verification + verify_rule(config, err_msg) return None |