#!/usr/bin/env python3 # # Copyright (C) 2021-2024 VyOS maintainers and contributors # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License version 2 or later as # published by the Free Software Foundation. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . import os import re from sys import exit from vyos.base import Warning from vyos.config import Config from vyos.configdict import is_node_changed from vyos.configdiff import get_config_diff, Diff from vyos.configdep import set_dependents, call_dependents from vyos.configverify import verify_interface_exists from vyos.ethtool import Ethtool from vyos.firewall import fqdn_config_parse from vyos.firewall import geoip_update from vyos.template import render from vyos.utils.dict import dict_search_args from vyos.utils.dict import dict_search_recursive from vyos.utils.process import call from vyos.utils.process import cmd from vyos.utils.process import rc_cmd from vyos import ConfigError from vyos import airbag from pathlib import Path airbag.enable() nftables_conf = '/run/nftables.conf' domain_resolver_usage = '/run/use-vyos-domain-resolver-firewall' domain_resolver_usage_nat = '/run/use-vyos-domain-resolver-nat' sysctl_file = r'/run/sysctl/10-vyos-firewall.conf' valid_groups = [ 'address_group', 'domain_group', 'network_group', 'port_group', 'interface_group' ] nested_group_types = [ 'address_group', 'network_group', 'mac_group', 'port_group', 'ipv6_address_group', 'ipv6_network_group' ] snmp_change_type = { 'unknown': 0, 'add': 1, 'delete': 2, 'change': 3 } snmp_event_source = 1 snmp_trap_mib = 'VYATTA-TRAP-MIB' snmp_trap_name = 'mgmtEventTrap' def geoip_updated(conf, firewall): diff = get_config_diff(conf) node_diff = diff.get_child_nodes_diff(['firewall'], expand_nodes=Diff.DELETE, recursive=True) out = { 'name': [], 'ipv6_name': [], 'deleted_name': [], 'deleted_ipv6_name': [] } updated = False for key, path in dict_search_recursive(firewall, 'geoip'): set_name = f'GEOIP_CC_{path[1]}_{path[2]}_{path[4]}' if (path[0] == 'ipv4'): out['name'].append(set_name) elif (path[0] == 'ipv6'): set_name = f'GEOIP_CC6_{path[1]}_{path[2]}_{path[4]}' out['ipv6_name'].append(set_name) updated = True if 'delete' in node_diff: for key, path in dict_search_recursive(node_diff['delete'], 'geoip'): set_name = f'GEOIP_CC_{path[1]}_{path[2]}_{path[4]}' if (path[0] == 'ipv4'): out['deleted_name'].append(set_name) elif (path[0] == 'ipv6'): set_name = f'GEOIP_CC_{path[1]}_{path[2]}_{path[4]}' out['deleted_ipv6_name'].append(set_name) updated = True if updated: return out return False def get_config(config=None): if config: conf = config else: conf = Config() base = ['firewall'] firewall = conf.get_config_dict(base, key_mangling=('-', '_'), no_tag_node_value_mangle=True, get_first_key=True, with_recursive_defaults=True) firewall['group_resync'] = bool('group' in firewall or is_node_changed(conf, base + ['group'])) if firewall['group_resync']: # Update nat and policy-route as firewall groups were updated set_dependents('group_resync', conf) firewall['geoip_updated'] = geoip_updated(conf, firewall) fqdn_config_parse(firewall, 'firewall') set_dependents('conntrack', conf) return firewall def verify_rule(firewall, rule_conf, ipv6): if 'action' not in rule_conf: raise ConfigError('Rule action must be defined') if 'jump' in rule_conf['action'] and 'jump_target' not in rule_conf: raise ConfigError('Action set to jump, but no jump-target specified') if 'jump_target' in rule_conf: if 'jump' not in rule_conf['action']: raise ConfigError('jump-target defined, but action jump needed and it is not defined') target = rule_conf['jump_target'] if not ipv6: if target not in dict_search_args(firewall, 'ipv4', 'name'): raise ConfigError(f'Invalid jump-target. Firewall name {target} does not exist on the system') else: if target not in dict_search_args(firewall, 'ipv6', 'name'): raise ConfigError(f'Invalid jump-target. Firewall ipv6 name {target} does not exist on the system') if rule_conf['action'] == 'offload': if 'offload_target' not in rule_conf: raise ConfigError('Action set to offload, but no offload-target specified') offload_target = rule_conf['offload_target'] if not dict_search_args(firewall, 'flowtable', offload_target): raise ConfigError(f'Invalid offload-target. Flowtable "{offload_target}" does not exist on the system') if rule_conf['action'] != 'synproxy' and 'synproxy' in rule_conf: raise ConfigError('"synproxy" option allowed only for action synproxy') if rule_conf['action'] == 'synproxy': if 'state' in rule_conf: raise ConfigError('For action "synproxy" state cannot be defined') if not rule_conf.get('synproxy', {}).get('tcp'): raise ConfigError('synproxy TCP MSS is not defined') if rule_conf.get('protocol', {}) != 'tcp': raise ConfigError('For action "synproxy" the protocol must be set to TCP') if 'queue_options' in rule_conf: if 'queue' not in rule_conf['action']: raise ConfigError('queue-options defined, but action queue needed and it is not defined') if 'fanout' in rule_conf['queue_options'] and ('queue' not in rule_conf or '-' not in rule_conf['queue']): raise ConfigError('queue-options fanout defined, then queue needs to be defined as a range') if 'queue' in rule_conf and 'queue' not in rule_conf['action']: raise ConfigError('queue defined, but action queue needed and it is not defined') if 'fragment' in rule_conf: if {'match_frag', 'match_non_frag'} <= set(rule_conf['fragment']): raise ConfigError('Cannot specify both "match-frag" and "match-non-frag"') if 'limit' in rule_conf: if 'rate' in rule_conf['limit']: rate_int = re.sub(r'\D', '', rule_conf['limit']['rate']) if int(rate_int) < 1: raise ConfigError('Limit rate integer cannot be less than 1') if 'ipsec' in rule_conf: if {'match_ipsec', 'match_non_ipsec'} <= set(rule_conf['ipsec']): raise ConfigError('Cannot specify both "match-ipsec" and "match-non-ipsec"') if 'recent' in rule_conf: if not {'count', 'time'} <= set(rule_conf['recent']): raise ConfigError('Recent "count" and "time" values must be defined') tcp_flags = dict_search_args(rule_conf, 'tcp', 'flags') if tcp_flags: if dict_search_args(rule_conf, 'protocol') != 'tcp': raise ConfigError('Protocol must be tcp when specifying tcp flags') not_flags = dict_search_args(rule_conf, 'tcp', 'flags', 'not') if not_flags: duplicates = [flag for flag in tcp_flags if flag in not_flags] if duplicates: raise ConfigError(f'Cannot match a tcp flag as set and not set') if 'protocol' in rule_conf: if rule_conf['protocol'] == 'icmp' and ipv6: raise ConfigError(f'Cannot match IPv4 ICMP protocol on IPv6, use ipv6-icmp') if rule_conf['protocol'] == 'ipv6-icmp' and not ipv6: raise ConfigError(f'Cannot match IPv6 ICMP protocol on IPv4, use icmp') for side in ['destination', 'source']: if side in rule_conf: side_conf = rule_conf[side] if len({'address', 'fqdn', 'geoip'} & set(side_conf)) > 1: raise ConfigError('Only one of address, fqdn or geoip can be specified') if 'group' in side_conf: if len({'address_group', 'network_group', 'domain_group'} & set(side_conf['group'])) > 1: raise ConfigError('Only one address-group, network-group or domain-group can be specified') for group in valid_groups: if group in side_conf['group']: group_name = side_conf['group'][group] fw_group = f'ipv6_{group}' if ipv6 and group in ['address_group', 'network_group'] else group error_group = fw_group.replace("_", "-") if group in ['address_group', 'network_group', 'domain_group']: types = [t for t in ['address', 'fqdn', 'geoip'] if t in side_conf] if types: raise ConfigError(f'{error_group} and {types[0]} cannot both be defined') if group_name and group_name[0] == '!': group_name = group_name[1:] group_obj = dict_search_args(firewall, 'group', fw_group, group_name) if group_obj is None: raise ConfigError(f'Invalid {error_group} "{group_name}" on firewall rule') if not group_obj: Warning(f'{error_group} "{group_name}" has no members!') if 'port' in side_conf or dict_search_args(side_conf, 'group', 'port_group'): if 'protocol' not in rule_conf: raise ConfigError('Protocol must be defined if specifying a port or port-group') if rule_conf['protocol'] not in ['tcp', 'udp', 'tcp_udp']: raise ConfigError('Protocol must be tcp, udp, or tcp_udp when specifying a port or port-group') if 'port' in side_conf and dict_search_args(side_conf, 'group', 'port_group'): raise ConfigError(f'{side} port-group and port cannot both be defined') if 'add_address_to_group' in rule_conf: for type in ['destination_address', 'source_address']: if type in rule_conf['add_address_to_group']: if 'address_group' not in rule_conf['add_address_to_group'][type]: raise ConfigError(f'Dynamic address group must be defined.') else: target = rule_conf['add_address_to_group'][type]['address_group'] fwall_group = 'ipv6_address_group' if ipv6 else 'address_group' group_obj = dict_search_args(firewall, 'group', 'dynamic_group', fwall_group, target) if group_obj is None: raise ConfigError(f'Invalid dynamic address group on firewall rule') if 'log_options' in rule_conf: if 'log' not in rule_conf: raise ConfigError('log-options defined, but log is not enable') if 'snapshot_length' in rule_conf['log_options'] and 'group' not in rule_conf['log_options']: raise ConfigError('log-options snapshot-length defined, but log group is not define') if 'queue_threshold' in rule_conf['log_options'] and 'group' not in rule_conf['log_options']: raise ConfigError('log-options queue-threshold defined, but log group is not define') for direction in ['inbound_interface','outbound_interface']: if direction in rule_conf: if 'name' in rule_conf[direction] and 'group' in rule_conf[direction]: raise ConfigError(f'Cannot specify both interface group and interface name for {direction}') if 'group' in rule_conf[direction]: group_name = rule_conf[direction]['group'] if group_name[0] == '!': group_name = group_name[1:] group_obj = dict_search_args(firewall, 'group', 'interface_group', group_name) if group_obj is None: raise ConfigError(f'Invalid interface group "{group_name}" on firewall rule') if not group_obj: Warning(f'interface-group "{group_name}" has no members!') def verify_nested_group(group_name, group, groups, seen): if 'include' not in group: return seen.append(group_name) for g in group['include']: if g not in groups: raise ConfigError(f'Nested group "{g}" does not exist') if g in seen: raise ConfigError(f'Group "{group_name}" has a circular reference') if 'include' in groups[g]: verify_nested_group(g, groups[g], groups, seen) def verify_hardware_offload(ifname): ethtool = Ethtool(ifname) enabled, fixed = ethtool.get_hw_tc_offload() if not enabled and fixed: raise ConfigError(f'Interface "{ifname}" does not support hardware offload') if not enabled: raise ConfigError(f'Interface "{ifname}" requires "offload hw-tc-offload"') def verify(firewall): if 'flowtable' in firewall: for flowtable, flowtable_conf in firewall['flowtable'].items(): if 'interface' not in flowtable_conf: raise ConfigError(f'Flowtable "{flowtable}" requires at least one interface') for ifname in flowtable_conf['interface']: verify_interface_exists(firewall, ifname) if dict_search_args(flowtable_conf, 'offload') == 'hardware': interfaces = flowtable_conf['interface'] for ifname in interfaces: verify_hardware_offload(ifname) if 'group' in firewall: for group_type in nested_group_types: if group_type in firewall['group']: groups = firewall['group'][group_type] for group_name, group in groups.items(): verify_nested_group(group_name, group, groups, []) if 'ipv4' in firewall: for name in ['name','forward','input','output', 'prerouting']: if name in firewall['ipv4']: for name_id, name_conf in firewall['ipv4'][name].items(): if 'jump' in name_conf['default_action'] and 'default_jump_target' not in name_conf: raise ConfigError('default-action set to jump, but no default-jump-target specified') if 'default_jump_target' in name_conf: target = name_conf['default_jump_target'] if 'jump' not in name_conf['default_action']: raise ConfigError('default-jump-target defined, but default-action jump needed and it is not defined') if name_conf['default_jump_target'] == name_id: raise ConfigError(f'Loop detected on default-jump-target.') ## Now need to check that default-jump-target exists (other firewall chain/name) if target not in dict_search_args(firewall['ipv4'], 'name'): raise ConfigError(f'Invalid jump-target. Firewall name {target} does not exist on the system') if 'rule' in name_conf: for rule_id, rule_conf in name_conf['rule'].items(): verify_rule(firewall, rule_conf, False) if 'ipv6' in firewall: for name in ['name','forward','input','output', 'prerouting']: if name in firewall['ipv6']: for name_id, name_conf in firewall['ipv6'][name].items(): if 'jump' in name_conf['default_action'] and 'default_jump_target' not in name_conf: raise ConfigError('default-action set to jump, but no default-jump-target specified') if 'default_jump_target' in name_conf: target = name_conf['default_jump_target'] if 'jump' not in name_conf['default_action']: raise ConfigError('default-jump-target defined, but default-action jump needed and it is not defined') if name_conf['default_jump_target'] == name_id: raise ConfigError(f'Loop detected on default-jump-target.') ## Now need to check that default-jump-target exists (other firewall chain/name) if target not in dict_search_args(firewall['ipv6'], 'name'): raise ConfigError(f'Invalid jump-target. Firewall name {target} does not exist on the system') if 'rule' in name_conf: for rule_id, rule_conf in name_conf['rule'].items(): verify_rule(firewall, rule_conf, True) #### ZONESSSS local_zone = False zone_interfaces = [] if 'zone' in firewall: for zone, zone_conf in firewall['zone'].items(): if 'local_zone' not in zone_conf and 'interface' not in zone_conf: raise ConfigError(f'Zone "{zone}" has no interfaces and is not the local zone') if 'local_zone' in zone_conf: if local_zone: raise ConfigError('There cannot be multiple local zones') if 'interface' in zone_conf: raise ConfigError('Local zone cannot have interfaces assigned') if 'intra_zone_filtering' in zone_conf: raise ConfigError('Local zone cannot use intra-zone-filtering') local_zone = True if 'interface' in zone_conf: found_duplicates = [intf for intf in zone_conf['interface'] if intf in zone_interfaces] if found_duplicates: raise ConfigError(f'Interfaces cannot be assigned to multiple zones') zone_interfaces += zone_conf['interface'] if 'intra_zone_filtering' in zone_conf: intra_zone = zone_conf['intra_zone_filtering'] if len(intra_zone) > 1: raise ConfigError('Only one intra-zone-filtering action must be specified') if 'firewall' in intra_zone: v4_name = dict_search_args(intra_zone, 'firewall', 'name') if v4_name and not dict_search_args(firewall, 'ipv4', 'name', v4_name): raise ConfigError(f'Firewall name "{v4_name}" does not exist') v6_name = dict_search_args(intra_zone, 'firewall', 'ipv6_name') if v6_name and not dict_search_args(firewall, 'ipv6', 'name', v6_name): raise ConfigError(f'Firewall ipv6-name "{v6_name}" does not exist') if not v4_name and not v6_name: raise ConfigError('No firewall names specified for intra-zone-filtering') if 'from' in zone_conf: for from_zone, from_conf in zone_conf['from'].items(): if from_zone not in firewall['zone']: raise ConfigError(f'Zone "{zone}" refers to a non-existent or deleted zone "{from_zone}"') v4_name = dict_search_args(from_conf, 'firewall', 'name') if v4_name and not dict_search_args(firewall, 'ipv4', 'name', v4_name): raise ConfigError(f'Firewall name "{v4_name}" does not exist') v6_name = dict_search_args(from_conf, 'firewall', 'ipv6_name') if v6_name and not dict_search_args(firewall, 'ipv6', 'name', v6_name): raise ConfigError(f'Firewall ipv6-name "{v6_name}" does not exist') return None def generate(firewall): if not os.path.exists(nftables_conf): firewall['first_install'] = True if 'zone' in firewall: for local_zone, local_zone_conf in firewall['zone'].items(): if 'local_zone' not in local_zone_conf: continue local_zone_conf['from_local'] = {} for zone, zone_conf in firewall['zone'].items(): if zone == local_zone or 'from' not in zone_conf: continue if local_zone in zone_conf['from']: local_zone_conf['from_local'][zone] = zone_conf['from'][local_zone] render(nftables_conf, 'firewall/nftables.j2', firewall) render(sysctl_file, 'firewall/sysctl-firewall.conf.j2', firewall) return None def apply(firewall): install_result, output = rc_cmd(f'nft --file {nftables_conf}') if install_result == 1: raise ConfigError(f'Failed to apply firewall: {output}') # Apply firewall global-options sysctl settings cmd(f'sysctl -f {sysctl_file}') call_dependents() ## DOMAIN RESOLVER domain_action = 'restart' if dict_search_args(firewall, 'group', 'domain_group') or firewall['ip_fqdn'].items() or firewall['ip6_fqdn'].items(): text = f'# Automatically generated by firewall.py\nThis file indicates that vyos-domain-resolver service is used by the firewall.\n' Path(domain_resolver_usage).write_text(text) else: Path(domain_resolver_usage).unlink(missing_ok=True) if not Path('/run').glob('use-vyos-domain-resolver*'): domain_action = 'stop' call(f'systemctl {domain_action} vyos-domain-resolver.service') if firewall['geoip_updated']: # Call helper script to Update set contents if 'name' in firewall['geoip_updated'] or 'ipv6_name' in firewall['geoip_updated']: print('Updating GeoIP. Please wait...') geoip_update(firewall) return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)