From 4ef110fd2c501b718344c72d495ad7e16d2bd465 Mon Sep 17 00:00:00 2001 From: Christian Breunig Date: Sat, 30 Dec 2023 23:25:20 +0100 Subject: T5474: establish common file name pattern for XML conf mode commands We will use _ as CLI level divider. The XML definition filename and also the Python helper should match the CLI node. Example: set interfaces ethernet -> interfaces_ethernet.xml.in set interfaces bond -> interfaces_bond.xml.in set service dhcp-server -> service_dhcp-server-xml.in --- src/conf_mode/system_conntrack.py | 243 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 243 insertions(+) create mode 100755 src/conf_mode/system_conntrack.py (limited to 'src/conf_mode/system_conntrack.py') diff --git a/src/conf_mode/system_conntrack.py b/src/conf_mode/system_conntrack.py new file mode 100755 index 000000000..7f6c71440 --- /dev/null +++ b/src/conf_mode/system_conntrack.py @@ -0,0 +1,243 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2021-2023 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.config import Config +from vyos.configdep import set_dependents, call_dependents +from vyos.utils.process import process_named_running +from vyos.utils.dict import dict_search +from vyos.utils.dict import dict_search_args +from vyos.utils.dict import dict_search_recursive +from vyos.utils.process import cmd +from vyos.utils.process import rc_cmd +from vyos.utils.process import run +from vyos.template import render +from vyos import ConfigError +from vyos import airbag +airbag.enable() + +conntrack_config = r'/etc/modprobe.d/vyatta_nf_conntrack.conf' +sysctl_file = r'/run/sysctl/10-vyos-conntrack.conf' +nftables_ct_file = r'/run/nftables-ct.conf' + +# Every ALG (Application Layer Gateway) consists of either a Kernel Object +# also called a Kernel Module/Driver or some rules present in iptables +module_map = { + 'ftp': { + 'ko': ['nf_nat_ftp', 'nf_conntrack_ftp'], + 'nftables': ['ct helper set "ftp_tcp" tcp dport {21} return'] + }, + 'h323': { + 'ko': ['nf_nat_h323', 'nf_conntrack_h323'], + 'nftables': ['ct helper set "ras_udp" udp dport {1719} return', + 'ct helper set "q931_tcp" tcp dport {1720} return'] + }, + 'nfs': { + 'nftables': ['ct helper set "rpc_tcp" tcp dport {111} return', + 'ct helper set "rpc_udp" udp dport {111} return'] + }, + 'pptp': { + 'ko': ['nf_nat_pptp', 'nf_conntrack_pptp'], + 'nftables': ['ct helper set "pptp_tcp" tcp dport {1723} return'], + 'ipv4': True + }, + 'sip': { + 'ko': ['nf_nat_sip', 'nf_conntrack_sip'], + 'nftables': ['ct helper set "sip_tcp" tcp dport {5060,5061} return', + 'ct helper set "sip_udp" udp dport {5060,5061} return'] + }, + 'sqlnet': { + 'nftables': ['ct helper set "tns_tcp" tcp dport {1521,1525,1536} return'] + }, + 'tftp': { + 'ko': ['nf_nat_tftp', 'nf_conntrack_tftp'], + 'nftables': ['ct helper set "tftp_udp" udp dport {69} return'] + }, +} + +valid_groups = [ + 'address_group', + 'domain_group', + 'network_group', + 'port_group' +] + +def get_config(config=None): + if config: + conf = config + else: + conf = Config() + base = ['system', 'conntrack'] + + conntrack = conf.get_config_dict(base, key_mangling=('-', '_'), + get_first_key=True, + with_recursive_defaults=True) + + conntrack['firewall'] = conf.get_config_dict(['firewall'], key_mangling=('-', '_'), + get_first_key=True, + no_tag_node_value_mangle=True) + + conntrack['ipv4_nat_action'] = 'accept' if conf.exists(['nat']) else 'return' + conntrack['ipv6_nat_action'] = 'accept' if conf.exists(['nat66']) else 'return' + conntrack['wlb_action'] = 'accept' if conf.exists(['load-balancing', 'wan']) else 'return' + conntrack['wlb_local_action'] = conf.exists(['load-balancing', 'wan', 'enable-local-traffic']) + + conntrack['module_map'] = module_map + + if conf.exists(['service', 'conntrack-sync']): + set_dependents('conntrack_sync', conf) + + return conntrack + +def verify(conntrack): + for inet in ['ipv4', 'ipv6']: + if dict_search_args(conntrack, 'ignore', inet, 'rule') != None: + for rule, rule_config in conntrack['ignore'][inet]['rule'].items(): + if dict_search('destination.port', rule_config) or \ + dict_search('destination.group.port_group', rule_config) or \ + dict_search('source.port', rule_config) or \ + dict_search('source.group.port_group', rule_config): + if 'protocol' not in rule_config or rule_config['protocol'] not in ['tcp', 'udp']: + raise ConfigError(f'Port requires tcp or udp as protocol in rule {rule}') + + tcp_flags = dict_search_args(rule_config, 'tcp', 'flags') + if tcp_flags: + if dict_search_args(rule_config, 'protocol') != 'tcp': + raise ConfigError('Protocol must be tcp when specifying tcp flags') + + not_flags = dict_search_args(rule_config, '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') + + for side in ['destination', 'source']: + if side in rule_config: + side_conf = rule_config[side] + + 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] + error_group = group.replace("_", "-") + + if group in ['address_group', 'network_group', 'domain_group']: + if 'address' in side_conf: + raise ConfigError(f'{error_group} and address cannot both be defined') + + if group_name and group_name[0] == '!': + group_name = group_name[1:] + + if inet == 'ipv6': + group = f'ipv6_{group}' + + group_obj = dict_search_args(conntrack['firewall'], 'group', group, group_name) + + if group_obj is None: + raise ConfigError(f'Invalid {error_group} "{group_name}" on ignore rule') + + if not group_obj: + Warning(f'{error_group} "{group_name}" has no members!') + + if dict_search_args(conntrack, 'timeout', 'custom', inet, 'rule') != None: + for rule, rule_config in conntrack['timeout']['custom'][inet]['rule'].items(): + if 'protocol' not in rule_config: + raise ConfigError(f'Conntrack custom timeout rule {rule} requires protocol tcp or udp') + else: + if 'tcp' in rule_config['protocol'] and 'udp' in rule_config['protocol']: + raise ConfigError(f'conntrack custom timeout rule {rule} - Cant use both tcp and udp protocol') + return None + +def generate(conntrack): + if not os.path.exists(nftables_ct_file): + conntrack['first_install'] = True + + # Determine if conntrack is needed + conntrack['ipv4_firewall_action'] = 'return' + conntrack['ipv6_firewall_action'] = 'return' + + for rules, path in dict_search_recursive(conntrack['firewall'], 'rule'): + if any(('state' in rule_conf or 'connection_status' in rule_conf or 'offload_target' in rule_conf) for rule_conf in rules.values()): + if path[0] == 'ipv4': + conntrack['ipv4_firewall_action'] = 'accept' + elif path[0] == 'ipv6': + conntrack['ipv6_firewall_action'] = 'accept' + + render(conntrack_config, 'conntrack/vyos_nf_conntrack.conf.j2', conntrack) + render(sysctl_file, 'conntrack/sysctl.conf.j2', conntrack) + render(nftables_ct_file, 'conntrack/nftables-ct.j2', conntrack) + return None + +def apply(conntrack): + # Depending on the enable/disable state of the ALG (Application Layer Gateway) + # modules we need to either insmod or rmmod the helpers. + + add_modules = [] + rm_modules = [] + + for module, module_config in module_map.items(): + if dict_search_args(conntrack, 'modules', module) is None: + if 'ko' in module_config: + unloaded = [mod for mod in module_config['ko'] if os.path.exists(f'/sys/module/{mod}')] + rm_modules.extend(unloaded) + else: + if 'ko' in module_config: + add_modules.extend(module_config['ko']) + + # Add modules before nftables uses them + if add_modules: + module_str = ' '.join(add_modules) + cmd(f'modprobe -a {module_str}') + + # Load new nftables ruleset + install_result, output = rc_cmd(f'nft -f {nftables_ct_file}') + if install_result == 1: + raise ConfigError(f'Failed to apply configuration: {output}') + + # Remove modules after nftables stops using them + if rm_modules: + module_str = ' '.join(rm_modules) + cmd(f'rmmod {module_str}') + + try: + call_dependents() + except ConfigError: + # Ignore config errors on dependent due to being called too early. Example: + # ConfigError("ConfigError('Interface ethN requires an IP address!')") + pass + + # We silently ignore all errors + # See: https://bugzilla.redhat.com/show_bug.cgi?id=1264080 + cmd(f'sysctl -f {sysctl_file}') + + return None + +if __name__ == '__main__': + try: + c = get_config() + verify(c) + generate(c) + apply(c) + except ConfigError as e: + print(e) + exit(1) -- cgit v1.2.3