#!/usr/bin/env python3 # # Copyright (C) 2019-2020 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 copy import deepcopy from sys import exit,stderr from ipaddress import ip_address,ip_network,IPv4Address,IPv4Network,IPv6Address,IPv6Network,summarize_address_range from netifaces import interfaces from time import sleep from shutil import rmtree from vyos.config import Config from vyos.configdict import list_diff from vyos.ifconfig import VTunIf from vyos.template import render from vyos.util import call, chown, chmod_600, chmod_755 from vyos.validate import is_addr_assigned, is_bridge_member, is_ipv4 from vyos import ConfigError user = 'openvpn' group = 'openvpn' default_config_data = { 'address': [], 'auth_user': '', 'auth_pass': '', 'auth_user_pass_file': '', 'auth': False, 'bridge_member': [], 'compress_lzo': False, 'deleted': False, 'description': '', 'disable': False, 'disable_ncp': False, 'encryption': '', 'hash': '', 'intf': '', 'ipv6_autoconf': 0, 'ipv6_eui64_prefix': [], 'ipv6_eui64_prefix_remove': [], 'ipv6_forwarding': 1, 'ipv6_dup_addr_detect': 1, 'ipv6_local_address': [], 'ipv6_remote_address': [], 'is_bridge_member': False, 'ping_restart': '60', 'ping_interval': '10', 'local_address': [], 'local_address_subnet': '', 'local_host': '', 'local_port': '', 'mode': '', 'ncp_ciphers': '', 'options': [], 'persistent_tunnel': False, 'protocol': 'udp', 'protocol_real': '', 'redirect_gateway': '', 'remote_address': [], 'remote_host': [], 'remote_port': '', 'client': [], 'server_domain': '', 'server_max_conn': '', 'server_dns_nameserver': [], 'server_pool': True, 'server_pool_start': '', 'server_pool_stop': '', 'server_pool_netmask': '', 'server_push_route': [], 'server_reject_unconfigured': False, 'server_subnet': [], 'server_topology': '', 'server_ipv6_dns_nameserver': [], 'server_ipv6_local': '', 'server_ipv6_prefixlen': '', 'server_ipv6_remote': '', 'server_ipv6_pool': True, 'server_ipv6_pool_base': '', 'server_ipv6_pool_prefixlen': '', 'server_ipv6_push_route': [], 'server_ipv6_subnet': [], 'shared_secret_file': '', 'tls': False, 'tls_auth': '', 'tls_ca_cert': '', 'tls_cert': '', 'tls_crl': '', 'tls_dh': '', 'tls_key': '', 'tls_crypt': '', 'tls_role': '', 'tls_version_min': '', 'type': 'tun', 'uid': user, 'gid': group, } def get_config_name(intf): cfg_file = f'/run/openvpn/{intf}.conf' return cfg_file def checkCertHeader(header, filename): """ Verify if filename contains specified header. Returns True if match is found, False if no match or file is not found """ if not os.path.isfile(filename): return False with open(filename, 'r') as f: for line in f: if re.match(header, line): return True return False def getDefaultServer(network, topology, devtype): """ Gets the default server parameters for a IPv4 "server" directive. Logic from openvpn's src/openvpn/helper.c. Returns a dict with addresses or False if the input parameters were incorrect. """ if not (devtype == 'tun' or devtype == 'tap'): return False if not network.version == 4: return False elif (devtype == 'tun' and network.prefixlen > 29) or (devtype == 'tap' and network.prefixlen > 30): return False server = { 'local': '', 'remote_netmask': '', 'client_remote_netmask': '', 'pool_start': '', 'pool_stop': '', 'pool_netmask': '' } if devtype == 'tun': if topology == 'net30' or topology == 'point-to-point': server['local'] = network[1] server['remote_netmask'] = network[2] server['client_remote_netmask'] = server['local'] # pool start is 4th host IP in subnet (.4 in a /24) server['pool_start'] = network[4] if network.prefixlen == 29: server['pool_stop'] = network.broadcast_address else: # pool end is -4 from the broadcast address (.251 in a /24) server['pool_stop'] = network[-5] elif topology == 'subnet': server['local'] = network[1] server['remote_netmask'] = str(network.netmask) server['client_remote_netmask'] = server['remote_netmask'] server['pool_start'] = network[2] server['pool_stop'] = network[-3] server['pool_netmask'] = server['remote_netmask'] elif devtype == 'tap': server['local'] = network[1] server['remote_netmask'] = str(network.netmask) server['client_remote_netmask'] = server['remote_netmask'] server['pool_start'] = network[2] server['pool_stop'] = network[-2] server['pool_netmask'] = server['remote_netmask'] return server def get_config(): openvpn = deepcopy(default_config_data) conf = Config() # determine tagNode instance if 'VYOS_TAGNODE_VALUE' not in os.environ: raise ConfigError('Interface (VYOS_TAGNODE_VALUE) not specified') openvpn['intf'] = os.environ['VYOS_TAGNODE_VALUE'] openvpn['auth_user_pass_file'] = f"/run/openvpn/{openvpn['intf']}.pw" # Check if interface instance has been removed if not conf.exists('interfaces openvpn ' + openvpn['intf']): openvpn['deleted'] = True # check if interface is member if a bridge openvpn['is_bridge_member'] = is_bridge_member(conf, openvpn['intf']) return openvpn # Check if we belong to any bridge interface for bridge in conf.list_nodes('interfaces bridge'): for intf in conf.list_nodes('interfaces bridge {} member interface'.format(bridge)): if intf == openvpn['intf']: openvpn['bridge_member'].append(intf) # bridged server should not have a pool by default (but can be specified manually) if openvpn['bridge_member']: openvpn['server_pool'] = False openvpn['server_ipv6_pool'] = False # set configuration level conf.set_level('interfaces openvpn ' + openvpn['intf']) # retrieve authentication options - username if conf.exists('authentication username'): openvpn['auth_user'] = conf.return_value('authentication username') openvpn['auth'] = True # retrieve authentication options - username if conf.exists('authentication password'): openvpn['auth_pass'] = conf.return_value('authentication password') openvpn['auth'] = True # retrieve interface description if conf.exists('description'): openvpn['description'] = conf.return_value('description') # interface device-type if conf.exists('device-type'): openvpn['type'] = conf.return_value('device-type') # disable interface if conf.exists('disable'): openvpn['disable'] = True # data encryption algorithm cipher if conf.exists('encryption cipher'): openvpn['encryption'] = conf.return_value('encryption cipher') # disable ncp-ciphers support if conf.exists('encryption disable-ncp'): openvpn['disable_ncp'] = True # data encryption algorithm ncp-list if conf.exists('encryption ncp-ciphers'): _ncp_ciphers = [] for enc in conf.return_values('encryption ncp-ciphers'): if enc == 'des': _ncp_ciphers.append('des-cbc') _ncp_ciphers.append('DES-CBC') elif enc == '3des': _ncp_ciphers.append('des-ede3-cbc') _ncp_ciphers.append('DES-EDE3-CBC') elif enc == 'aes128': _ncp_ciphers.append('aes-128-cbc') _ncp_ciphers.append('AES-128-CBC') elif enc == 'aes128gcm': _ncp_ciphers.append('aes-128-gcm') _ncp_ciphers.append('AES-128-GCM') elif enc == 'aes192': _ncp_ciphers.append('aes-192-cbc') _ncp_ciphers.append('AES-192-CBC') elif enc == 'aes192gcm': _ncp_ciphers.append('aes-192-gcm') _ncp_ciphers.append('AES-192-GCM') elif enc == 'aes256': _ncp_ciphers.append('aes-256-cbc') _ncp_ciphers.append('AES-256-CBC') elif enc == 'aes256gcm': _ncp_ciphers.append('aes-256-gcm') _ncp_ciphers.append('AES-256-GCM') openvpn['ncp_ciphers'] = ':'.join(_ncp_ciphers) # hash algorithm if conf.exists('hash'): openvpn['hash'] = conf.return_value('hash') # Maximum number of keepalive packet failures if conf.exists('keep-alive failure-count') and conf.exists('keep-alive interval'): fail_count = conf.return_value('keep-alive failure-count') interval = conf.return_value('keep-alive interval') openvpn['ping_interval' ] = interval openvpn['ping_restart' ] = int(interval) * int(fail_count) # Local IP address of tunnel - even as it is a tag node - we can only work # on the first address if conf.exists('local-address'): for tmp in conf.list_nodes('local-address'): tmp_ip = ip_address(tmp) if tmp_ip.version == 4: openvpn['local_address'].append(tmp) if conf.exists('local-address {} subnet-mask'.format(tmp)): openvpn['local_address_subnet'] = conf.return_value('local-address {} subnet-mask'.format(tmp)) elif tmp_ip.version == 6: # input IPv6 address could be expanded so get the compressed version openvpn['ipv6_local_address'].append(str(tmp_ip)) # Local IP address to accept connections if conf.exists('local-host'): openvpn['local_host'] = conf.return_value('local-host') # Local port number to accept connections if conf.exists('local-port'): openvpn['local_port'] = conf.return_value('local-port') # Enable acquisition of IPv6 address using stateless autoconfig (SLAAC) if conf.exists('ipv6 address autoconf'): openvpn['ipv6_autoconf'] = 1 # Get prefixes for IPv6 addressing based on MAC address (EUI-64) if conf.exists('ipv6 address eui64'): openvpn['ipv6_eui64_prefix'] = conf.return_values('ipv6 address eui64') # Determine currently effective EUI64 addresses - to determine which # address is no longer valid and needs to be removed eff_addr = conf.return_effective_values('ipv6 address eui64') openvpn['ipv6_eui64_prefix_remove'] = list_diff(eff_addr, openvpn['ipv6_eui64_prefix']) # Remove the default link-local address if set. if conf.exists('ipv6 address no-default-link-local'): openvpn['ipv6_eui64_prefix_remove'].append('fe80::/64') else: # add the link-local by default to make IPv6 work openvpn['ipv6_eui64_prefix'].append('fe80::/64') # Disable IPv6 forwarding on this interface if conf.exists('ipv6 disable-forwarding'): openvpn['ipv6_forwarding'] = 0 # IPv6 Duplicate Address Detection (DAD) tries if conf.exists('ipv6 dup-addr-detect-transmits'): openvpn['ipv6_dup_addr_detect'] = int(conf.return_value('ipv6 dup-addr-detect-transmits')) # OpenVPN operation mode if conf.exists('mode'): openvpn['mode'] = conf.return_value('mode') # Additional OpenVPN options if conf.exists('openvpn-option'): openvpn['options'] = conf.return_values('openvpn-option') # Do not close and reopen interface if conf.exists('persistent-tunnel'): openvpn['persistent_tunnel'] = True # Communication protocol if conf.exists('protocol'): openvpn['protocol'] = conf.return_value('protocol') # IP address of remote end of tunnel if conf.exists('remote-address'): for tmp in conf.return_values('remote-address'): tmp_ip = ip_address(tmp) if tmp_ip.version == 4: openvpn['remote_address'].append(tmp) elif tmp_ip.version == 6: openvpn['ipv6_remote_address'].append(str(tmp_ip)) # Remote host to connect to (dynamic if not set) if conf.exists('remote-host'): openvpn['remote_host'] = conf.return_values('remote-host') # Remote port number to connect to if conf.exists('remote-port'): openvpn['remote_port'] = conf.return_value('remote-port') # OpenVPN tunnel to be used as the default route # see https://openvpn.net/community-resources/reference-manual-for-openvpn-2-4/ # redirect-gateway flags if conf.exists('replace-default-route'): openvpn['redirect_gateway'] = 'def1' if conf.exists('replace-default-route local'): openvpn['redirect_gateway'] = 'local def1' # Topology for clients if conf.exists('server topology'): openvpn['server_topology'] = conf.return_value('server topology') # Server-mode subnet (from which client IPs are allocated) server_network_v4 = None server_network_v6 = None if conf.exists('server subnet'): for tmp in conf.return_values('server subnet'): tmp_ip = ip_network(tmp) if tmp_ip.version == 4: server_network_v4 = tmp_ip # convert the network to format: "192.0.2.0 255.255.255.0" for later use in template openvpn['server_subnet'].append(tmp_ip.with_netmask.replace(r'/', ' ')) elif tmp_ip.version == 6: server_network_v6 = tmp_ip openvpn['server_ipv6_subnet'].append(str(tmp_ip)) # Client-specific settings for client in conf.list_nodes('server client'): # set configuration level conf.set_level('interfaces openvpn ' + openvpn['intf'] + ' server client ' + client) data = { 'name': client, 'disable': False, 'ip': [], 'ipv6_ip': [], 'ipv6_remote': '', 'ipv6_push_route': [], 'ipv6_subnet': [], 'push_route': [], 'subnet': [], 'remote_netmask': '' } # Option to disable client connection if conf.exists('disable'): data['disable'] = True # IP address of the client for tmp in conf.return_values('ip'): tmp_ip = ip_address(tmp) if tmp_ip.version == 4: data['ip'].append(tmp) elif tmp_ip.version == 6: data['ipv6_ip'].append(str(tmp_ip)) # Route to be pushed to the client for tmp in conf.return_values('push-route'): tmp_ip = ip_network(tmp) if tmp_ip.version == 4: data['push_route'].append(tmp_ip.with_netmask.replace(r'/', ' ')) elif tmp_ip.version == 6: data['ipv6_push_route'].append(str(tmp_ip)) # Subnet belonging to the client for tmp in conf.return_values('subnet'): tmp_ip = ip_network(tmp) if tmp_ip.version == 4: data['subnet'].append(tmp_ip.with_netmask.replace(r'/', ' ')) elif tmp_ip.version == 6: data['ipv6_subnet'].append(str(tmp_ip)) # Append to global client list openvpn['client'].append(data) # re-set configuration level conf.set_level('interfaces openvpn ' + openvpn['intf']) # Server client IP pool if conf.exists('server client-ip-pool'): conf.set_level('interfaces openvpn ' + openvpn['intf'] + ' server client-ip-pool') # enable or disable server_pool where necessary # default is enabled, or disabled in bridge mode openvpn['server_pool'] = not conf.exists('disable') if conf.exists('start'): openvpn['server_pool_start'] = conf.return_value('start') if conf.exists('stop'): openvpn['server_pool_stop'] = conf.return_value('stop') if conf.exists('netmask'): openvpn['server_pool_netmask'] = conf.return_value('netmask') conf.set_level('interfaces openvpn ' + openvpn['intf']) # Server client IPv6 pool if conf.exists('server client-ipv6-pool'): conf.set_level('interfaces openvpn ' + openvpn['intf'] + ' server client-ipv6-pool') openvpn['server_ipv6_pool'] = not conf.exists('disable') if conf.exists('base'): tmp = conf.return_value('base').split('/') openvpn['server_ipv6_pool_base'] = str(IPv6Address(tmp[0])) if 1 < len(tmp): openvpn['server_ipv6_pool_prefixlen'] = tmp[1] conf.set_level('interfaces openvpn ' + openvpn['intf']) # DNS suffix to be pushed to all clients if conf.exists('server domain-name'): openvpn['server_domain'] = conf.return_value('server domain-name') # Number of maximum client connections if conf.exists('server max-connections'): openvpn['server_max_conn'] = conf.return_value('server max-connections') # Domain Name Server (DNS) if conf.exists('server name-server'): for tmp in conf.return_values('server name-server'): tmp_ip = ip_address(tmp) if tmp_ip.version == 4: openvpn['server_dns_nameserver'].append(tmp) elif tmp_ip.version == 6: openvpn['server_ipv6_dns_nameserver'].append(str(tmp_ip)) # Route to be pushed to all clients if conf.exists('server push-route'): for tmp in conf.return_values('server push-route'): tmp_ip = ip_network(tmp) if tmp_ip.version == 4: openvpn['server_push_route'].append(tmp_ip.with_netmask.replace(r'/', ' ')) elif tmp_ip.version == 6: openvpn['server_ipv6_push_route'].append(str(tmp_ip)) # Reject connections from clients that are not explicitly configured if conf.exists('server reject-unconfigured-clients'): openvpn['server_reject_unconfigured'] = True # File containing TLS auth static key if conf.exists('tls auth-file'): openvpn['tls_auth'] = conf.return_value('tls auth-file') openvpn['tls'] = True # File containing certificate for Certificate Authority (CA) if conf.exists('tls ca-cert-file'): openvpn['tls_ca_cert'] = conf.return_value('tls ca-cert-file') openvpn['tls'] = True # File containing certificate for this host if conf.exists('tls cert-file'): openvpn['tls_cert'] = conf.return_value('tls cert-file') openvpn['tls'] = True # File containing certificate revocation list (CRL) for this host if conf.exists('tls crl-file'): openvpn['tls_crl'] = conf.return_value('tls crl-file') openvpn['tls'] = True # File containing Diffie Hellman parameters (server only) if conf.exists('tls dh-file'): openvpn['tls_dh'] = conf.return_value('tls dh-file') openvpn['tls'] = True # File containing this host's private key if conf.exists('tls key-file'): openvpn['tls_key'] = conf.return_value('tls key-file') openvpn['tls'] = True # File containing key to encrypt control channel packets if conf.exists('tls crypt-file'): openvpn['tls_crypt'] = conf.return_value('tls crypt-file') openvpn['tls'] = True # Role in TLS negotiation if conf.exists('tls role'): openvpn['tls_role'] = conf.return_value('tls role') openvpn['tls'] = True # Minimum required TLS version if conf.exists('tls tls-version-min'): openvpn['tls_version_min'] = conf.return_value('tls tls-version-min') openvpn['tls'] = True if conf.exists('shared-secret-key-file'): openvpn['shared_secret_file'] = conf.return_value('shared-secret-key-file') if conf.exists('use-lzo-compression'): openvpn['compress_lzo'] = True # Special case when using EC certificates: # if key-file is EC and dh-file is unset, set tls_dh to 'none' if not openvpn['tls_dh'] and openvpn['tls_key'] and checkCertHeader('-----BEGIN EC PRIVATE KEY-----', openvpn['tls_key']): openvpn['tls_dh'] = 'none' # set default server topology to net30 if openvpn['mode'] == 'server' and not openvpn['server_topology']: openvpn['server_topology'] = 'net30' # Convert protocol to real protocol used by openvpn. # To make openvpn listen on both IPv4 and IPv6 we must use *6 protocols # (https://community.openvpn.net/openvpn/ticket/360), unless local is IPv4 # in which case it must use the standard protocols. # Note: this will break openvpn if IPv6 is disabled on the system. # This currently isn't supported, a check can be added in the future. if openvpn['protocol'] == 'tcp-active': openvpn['protocol_real'] = 'tcp6-client' elif openvpn['protocol'] == 'tcp-passive': openvpn['protocol_real'] = 'tcp6-server' else: openvpn['protocol_real'] = 'udp6' if is_ipv4(openvpn['local_host']): # takes out the '6' openvpn['protocol_real'] = openvpn['protocol_real'][:3] + openvpn['protocol_real'][4:] # Set defaults where necessary. # If any of the input parameters are wrong, # this will return False and no defaults will be set. if server_network_v4 and openvpn['server_topology'] and openvpn['type']: default_server = None default_server = getDefaultServer(server_network_v4, openvpn['server_topology'], openvpn['type']) if default_server: # server-bridge doesn't require a pool so don't set defaults for it if openvpn['server_pool'] and not openvpn['bridge_member']: if not openvpn['server_pool_start']: openvpn['server_pool_start'] = default_server['pool_start'] if not openvpn['server_pool_stop']: openvpn['server_pool_stop'] = default_server['pool_stop'] if not openvpn['server_pool_netmask']: openvpn['server_pool_netmask'] = default_server['pool_netmask'] for client in openvpn['client']: client['remote_netmask'] = default_server['client_remote_netmask'] if server_network_v6: if not openvpn['server_ipv6_local']: openvpn['server_ipv6_local'] = server_network_v6[1] if not openvpn['server_ipv6_prefixlen']: openvpn['server_ipv6_prefixlen'] = server_network_v6.prefixlen if not openvpn['server_ipv6_remote']: openvpn['server_ipv6_remote'] = server_network_v6[2] if openvpn['server_ipv6_pool'] and server_network_v6.prefixlen < 112: if not openvpn['server_ipv6_pool_base']: openvpn['server_ipv6_pool_base'] = server_network_v6[0x1000] if not openvpn['server_ipv6_pool_prefixlen']: openvpn['server_ipv6_pool_prefixlen'] = openvpn['server_ipv6_prefixlen'] for client in openvpn['client']: client['ipv6_remote'] = openvpn['server_ipv6_local'] if openvpn['redirect_gateway']: openvpn['redirect_gateway'] += ' ipv6' return openvpn def verify(openvpn): if openvpn['deleted']: if openvpn['is_bridge_member']: interface = openvpn['intf'] bridge = openvpn['is_bridge_member'] raise ConfigError(f'Interface "{interface}" can not be deleted as it belongs to bridge "{bridge}"!') return None if not openvpn['mode']: raise ConfigError('Must specify OpenVPN operation mode') # Checks which need to be performed on interface rmeoval if openvpn['deleted']: # OpenVPN interface can not be deleted if it's still member of a bridge if openvpn['bridge_member']: raise ConfigError('Can not delete {} as it is a member interface of bridge {}!'.format(openvpn['intf'], bridge)) # Check if we have disabled ncp and at the same time specified ncp-ciphers if openvpn['disable_ncp'] and openvpn['ncp_ciphers']: raise ConfigError('Cannot specify both "encryption disable-ncp" and "encryption ncp-ciphers"') # # OpenVPN client mode - VERIFY # if openvpn['mode'] == 'client': if openvpn['local_port']: raise ConfigError('Cannot specify "local-port" in client mode') if openvpn['local_host']: raise ConfigError('Cannot specify "local-host" in client mode') if openvpn['protocol'] == 'tcp-passive': raise ConfigError('Protocol "tcp-passive" is not valid in client mode') if not openvpn['remote_host']: raise ConfigError('Must specify "remote-host" in client mode') if openvpn['tls_dh'] and openvpn['tls_dh'] != 'none': raise ConfigError('Cannot specify "tls dh-file" in client mode') # # OpenVPN site-to-site - VERIFY # if openvpn['mode'] == 'site-to-site': if openvpn['ncp_ciphers']: raise ConfigError('encryption ncp-ciphers cannot be specified in site-to-site mode, only server or client') if openvpn['mode'] == 'site-to-site' and not openvpn['bridge_member']: if not (openvpn['local_address'] or openvpn['ipv6_local_address']): raise ConfigError('Must specify "local-address" or "bridge member interface"') if len(openvpn['local_address']) > 1 or len(openvpn['ipv6_local_address']) > 1: raise ConfigError('Cannot specify more than 1 IPv4 and 1 IPv6 "local-address"') if len(openvpn['remote_address']) > 1 or len(openvpn['ipv6_remote_address']) > 1: raise ConfigError('Cannot specify more than 1 IPv4 and 1 IPv6 "remote-address"') for host in openvpn['remote_host']: if host in openvpn['remote_address'] or host in openvpn['ipv6_remote_address']: raise ConfigError('"remote-address" cannot be the same as "remote-host"') if openvpn['local_address'] and not (openvpn['remote_address'] or openvpn['local_address_subnet']): raise ConfigError('IPv4 "local-address" requires IPv4 "remote-address" or IPv4 "local-address subnet"') if openvpn['remote_address'] and not openvpn['local_address']: raise ConfigError('IPv4 "remote-address" requires IPv4 "local-address"') if openvpn['ipv6_local_address'] and not openvpn['ipv6_remote_address']: raise ConfigError('IPv6 "local-address" requires IPv6 "remote-address"') if openvpn['ipv6_remote_address'] and not openvpn['ipv6_local_address']: raise ConfigError('IPv6 "remote-address" requires IPv6 "local-address"') if openvpn['type'] == 'tun': if not (openvpn['remote_address'] or openvpn['ipv6_remote_address']): raise ConfigError('Must specify "remote-address"') if ( (openvpn['local_address'] and openvpn['local_address'] == openvpn['remote_address']) or (openvpn['ipv6_local_address'] and openvpn['ipv6_local_address'] == openvpn['ipv6_remote_address']) ): raise ConfigError('"local-address" and "remote-address" cannot be the same') if openvpn['local_host'] in openvpn['local_address'] or openvpn['local_host'] in openvpn['ipv6_local_address']: raise ConfigError('"local-address" cannot be the same as "local-host"') else: # checks for client-server or site-to-site bridged if openvpn['local_address'] or openvpn['ipv6_local_address'] or openvpn['remote_address'] or openvpn['ipv6_remote_address']: raise ConfigError('Cannot specify "local-address" or "remote-address" in client-server or bridge mode') # # OpenVPN server mode - VERIFY # if openvpn['mode'] == 'server': if openvpn['protocol'] == 'tcp-active': raise ConfigError('Protocol "tcp-active" is not valid in server mode') if openvpn['remote_port']: raise ConfigError('Cannot specify "remote-port" in server mode') if openvpn['remote_host']: raise ConfigError('Cannot specify "remote-host" in server mode') if openvpn['protocol'] == 'tcp-passive' and len(openvpn['remote_host']) > 1: raise ConfigError('Cannot specify more than 1 "remote-host" with "tcp-passive"') if not openvpn['tls_dh'] and not checkCertHeader('-----BEGIN EC PRIVATE KEY-----', openvpn['tls_key']): raise ConfigError('Must specify "tls dh-file" when not using EC keys in server mode') if len(openvpn['server_subnet']) > 1 or len(openvpn['server_ipv6_subnet']) > 1: raise ConfigError('Cannot specify more than 1 IPv4 and 1 IPv6 server subnet') for client in openvpn['client']: if len(client['ip']) > 1 or len(client['ipv6_ip']) > 1: raise ConfigError(f'Server client "{client["name"]}": cannot specify more than 1 IPv4 and 1 IPv6 IP') if openvpn['server_subnet']: subnet = IPv4Network(openvpn['server_subnet'][0].replace(' ', '/')) if openvpn['type'] == 'tun' and subnet.prefixlen > 29: raise ConfigError('Server subnets smaller than /29 with device type "tun" are not supported') elif openvpn['type'] == 'tap' and subnet.prefixlen > 30: raise ConfigError('Server subnets smaller than /30 with device type "tap" are not supported') for client in openvpn['client']: if client['ip'] and not IPv4Address(client['ip'][0]) in subnet: raise ConfigError(f'Client "{client["name"]}" IP {client["ip"][0]} not in server subnet {subnet}') else: if not openvpn['bridge_member']: raise ConfigError('Must specify "server subnet" or "bridge member interface" in server mode') if openvpn['server_pool']: if not (openvpn['server_pool_start'] and openvpn['server_pool_stop']): raise ConfigError('Server client-ip-pool requires both start and stop addresses in bridged mode') else: v4PoolStart = IPv4Address(openvpn['server_pool_start']) v4PoolStop = IPv4Address(openvpn['server_pool_stop']) if v4PoolStart > v4PoolStop: raise ConfigError(f'Server client-ip-pool start address {v4PoolStart} is larger than stop address {v4PoolStop}') v4PoolSize = int(v4PoolStop) - int(v4PoolStart) if v4PoolSize >= 65536: raise ConfigError(f'Server client-ip-pool is too large [{v4PoolStart} -> {v4PoolStop} = {v4PoolSize}], maximum is 65536 addresses.') v4PoolNets = list(summarize_address_range(v4PoolStart, v4PoolStop)) for client in openvpn['client']: if client['ip']: for v4PoolNet in v4PoolNets: if IPv4Address(client['ip'][0]) in v4PoolNet: print(f'Warning: Client "{client["name"]}" IP {client["ip"][0]} is in server IP pool, it is not reserved for this client.', file=stderr) if openvpn['server_ipv6_subnet']: if not openvpn['server_subnet']: raise ConfigError('IPv6 server requires an IPv4 server subnet') if openvpn['server_ipv6_pool']: if not openvpn['server_pool']: raise ConfigError('IPv6 server pool requires an IPv4 server pool') if int(openvpn['server_ipv6_pool_prefixlen']) >= 112: raise ConfigError('IPv6 server pool must be larger than /112') v6PoolStart = IPv6Address(openvpn['server_ipv6_pool_base']) v6PoolStop = IPv6Network((v6PoolStart, openvpn['server_ipv6_pool_prefixlen']), strict=False)[-1] # don't remove the parentheses, it's a 2-tuple v6PoolSize = int(v6PoolStop) - int(v6PoolStart) if int(openvpn['server_ipv6_pool_prefixlen']) > 96 else 65536 if v6PoolSize < v4PoolSize: raise ConfigError(f'IPv6 server pool must be at least as large as the IPv4 pool (current sizes: IPv6={v6PoolSize} IPv4={v4PoolSize})') v6PoolNets = list(summarize_address_range(v6PoolStart, v6PoolStop)) for client in openvpn['client']: if client['ipv6_ip']: for v6PoolNet in v6PoolNets: if IPv6Address(client['ipv6_ip'][0]) in v6PoolNet: print(f'Warning: Client "{client["name"]}" IP {client["ipv6_ip"][0]} is in server IP pool, it is not reserved for this client.', file=stderr) else: if openvpn['server_ipv6_push_route']: raise ConfigError('IPv6 push-route requires an IPv6 server subnet') for client in openvpn ['client']: if client['ipv6_ip']: raise ConfigError(f'Server client "{client["name"]}" IPv6 IP requires an IPv6 server subnet') if client['ipv6_push_route']: raise ConfigError(f'Server client "{client["name"]} IPv6 push-route requires an IPv6 server subnet"') if client['ipv6_subnet']: raise ConfigError(f'Server client "{client["name"]} IPv6 subnet requires an IPv6 server subnet"') else: # checks for both client and site-to-site go here if openvpn['server_reject_unconfigured']: raise ConfigError('reject-unconfigured-clients is only supported in OpenVPN server mode') if openvpn['server_topology']: raise ConfigError('The "topology" option is only valid in server mode') if (not openvpn['remote_host']) and openvpn['redirect_gateway']: raise ConfigError('Cannot set "replace-default-route" without "remote-host"') # # OpenVPN common verification section # not depending on any operation mode # # verify specified IP address is present on any interface on this system if openvpn['local_host']: if not is_addr_assigned(openvpn['local_host']): raise ConfigError('No interface on system with specified local-host IP address: {}'.format(openvpn['local_host'])) # TCP active if openvpn['protocol'] == 'tcp-active': if openvpn['local_port']: raise ConfigError('Cannot specify "local-port" with "tcp-active"') if not openvpn['remote_host']: raise ConfigError('Must specify "remote-host" with "tcp-active"') # shared secret and TLS if not (openvpn['shared_secret_file'] or openvpn['tls']): raise ConfigError('Must specify one of "shared-secret-key-file" and "tls"') if openvpn['shared_secret_file'] and openvpn['tls']: raise ConfigError('Can only specify one of "shared-secret-key-file" and "tls"') if openvpn['mode'] in ['client', 'server']: if not openvpn['tls']: raise ConfigError('Must specify "tls" in client-server mode') # # TLS/encryption # if openvpn['shared_secret_file']: if openvpn['encryption'] in ['aes128gcm', 'aes192gcm', 'aes256gcm']: raise ConfigError('GCM encryption with shared-secret-key-file is not supported') if not checkCertHeader('-----BEGIN OpenVPN Static key V1-----', openvpn['shared_secret_file']): raise ConfigError('Specified shared-secret-key-file "{}" is not valid'.format(openvpn['shared_secret_file'])) if openvpn['tls']: if not openvpn['tls_ca_cert']: raise ConfigError('Must specify "tls ca-cert-file"') if not (openvpn['mode'] == 'client' and openvpn['auth']): if not openvpn['tls_cert']: raise ConfigError('Must specify "tls cert-file"') if not openvpn['tls_key']: raise ConfigError('Must specify "tls key-file"') if openvpn['tls_auth'] and openvpn['tls_crypt']: raise ConfigError('TLS auth and crypt are mutually exclusive') if not checkCertHeader('-----BEGIN CERTIFICATE-----', openvpn['tls_ca_cert']): raise ConfigError('Specified ca-cert-file "{}" is invalid'.format(openvpn['tls_ca_cert'])) if openvpn['tls_auth']: if not checkCertHeader('-----BEGIN OpenVPN Static key V1-----', openvpn['tls_auth']): raise ConfigError('Specified auth-file "{}" is invalid'.format(openvpn['tls_auth'])) if openvpn['tls_cert']: if not checkCertHeader('-----BEGIN CERTIFICATE-----', openvpn['tls_cert']): raise ConfigError('Specified cert-file "{}" is invalid'.format(openvpn['tls_cert'])) if openvpn['tls_key']: if not checkCertHeader('-----BEGIN (?:RSA |EC )?PRIVATE KEY-----', openvpn['tls_key']): raise ConfigError('Specified key-file "{}" is not valid'.format(openvpn['tls_key'])) if openvpn['tls_crypt']: if not checkCertHeader('-----BEGIN OpenVPN Static key V1-----', openvpn['tls_crypt']): raise ConfigError('Specified TLS crypt-file "{}" is invalid'.format(openvpn['tls_crypt'])) if openvpn['tls_crl']: if not checkCertHeader('-----BEGIN X509 CRL-----', openvpn['tls_crl']): raise ConfigError('Specified crl-file "{} not valid'.format(openvpn['tls_crl'])) if openvpn['tls_dh'] and openvpn['tls_dh'] != 'none': if not checkCertHeader('-----BEGIN DH PARAMETERS-----', openvpn['tls_dh']): raise ConfigError('Specified dh-file "{}" is not valid'.format(openvpn['tls_dh'])) if openvpn['tls_role']: if openvpn['mode'] in ['client', 'server']: if not openvpn['tls_auth']: raise ConfigError('Cannot specify "tls role" in client-server mode') if openvpn['tls_role'] == 'active': if openvpn['protocol'] == 'tcp-passive': raise ConfigError('Cannot specify "tcp-passive" when "tls role" is "active"') if openvpn['tls_dh'] and openvpn['tls_dh'] != 'none': raise ConfigError('Cannot specify "tls dh-file" when "tls role" is "active"') elif openvpn['tls_role'] == 'passive': if openvpn['protocol'] == 'tcp-active': raise ConfigError('Cannot specify "tcp-active" when "tls role" is "passive"') if not openvpn['tls_dh']: raise ConfigError('Must specify "tls dh-file" when "tls role" is "passive"') if openvpn['tls_key'] and checkCertHeader('-----BEGIN EC PRIVATE KEY-----', openvpn['tls_key']): if openvpn['tls_dh'] and openvpn['tls_dh'] != 'none': print('Warning: using dh-file and EC keys simultaneously will lead to DH ciphers being used instead of ECDH') else: print('Diffie-Hellman prime file is unspecified, assuming ECDH') # # Auth user/pass # if openvpn['auth']: if not openvpn['auth_user']: raise ConfigError('Username for authentication is missing') if not openvpn['auth_pass']: raise ConfigError('Password for authentication is missing') return None def generate(openvpn): interface = openvpn['intf'] directory = os.path.dirname(get_config_name(interface)) # we can't know in advance which clients have been removed, # thus all client configs will be removed and re-added on demand ccd_dir = os.path.join(directory, 'ccd', interface) if os.path.isdir(ccd_dir): rmtree(ccd_dir, ignore_errors=True) if openvpn['deleted'] or openvpn['disable']: return None # create config directory on demand directories = [] directories.append(f'{directory}/status') directories.append(f'{directory}/ccd/{interface}') for onedir in directories: if not os.path.exists(onedir): os.makedirs(onedir, 0o755) chown(onedir, user, group) # Fix file permissons for keys fix_permissions = [] fix_permissions.append(openvpn['shared_secret_file']) fix_permissions.append(openvpn['tls_key']) # Generate User/Password authentication file if openvpn['auth']: with open(openvpn['auth_user_pass_file'], 'w') as f: f.write('{}\n{}'.format(openvpn['auth_user'], openvpn['auth_pass'])) # also change permission on auth file fix_permissions.append(openvpn['auth_user_pass_file']) else: # delete old auth file if present if os.path.isfile(openvpn['auth_user_pass_file']): os.remove(openvpn['auth_user_pass_file']) # Generate client specific configuration for client in openvpn['client']: client_file = os.path.join(ccd_dir, client['name']) render(client_file, 'openvpn/client.conf.tmpl', client) chown(client_file, user, group) # we need to support quoting of raw parameters from OpenVPN CLI # see https://phabricator.vyos.net/T1632 render(get_config_name(interface), 'openvpn/server.conf.tmpl', openvpn, formater=lambda _: _.replace(""", '"')) chown(get_config_name(interface), user, group) # Fixup file permissions for file in fix_permissions: chmod_600(file) return None def apply(openvpn): interface = openvpn['intf'] call(f'systemctl stop openvpn@{interface}.service') # Do some cleanup when OpenVPN is disabled/deleted if openvpn['deleted'] or openvpn['disable']: # cleanup old configuration files cleanup = [] cleanup.append(get_config_name(interface)) cleanup.append(openvpn['auth_user_pass_file']) for file in cleanup: if os.path.isfile(file): os.unlink(file) return None # On configuration change we need to wait for the 'old' interface to # vanish from the Kernel, if it is not gone, OpenVPN will report: # ERROR: Cannot ioctl TUNSETIFF vtun10: Device or resource busy (errno=16) while interface in interfaces(): sleep(0.250) # 250ms # No matching OpenVPN process running - maybe it got killed or none # existed - nevertheless, spawn new OpenVPN process call(f'systemctl start openvpn@{interface}.service') # better late then sorry ... but we can only set interface alias after # OpenVPN has been launched and created the interface cnt = 0 while interface not in interfaces(): # If VPN tunnel can't be established because the peer/server isn't # (temporarily) available, the vtun interface never becomes registered # with the kernel, and the commit would hang if there is no bail out # condition cnt += 1 if cnt == 50: break # sleep 250ms sleep(0.250) try: # we need to catch the exception if the interface is not up due to # reason stated above o = VTunIf(interface) # update interface description used e.g. within SNMP o.set_alias(openvpn['description']) # IPv6 address autoconfiguration o.set_ipv6_autoconf(openvpn['ipv6_autoconf']) # IPv6 forwarding o.set_ipv6_forwarding(openvpn['ipv6_forwarding']) # IPv6 Duplicate Address Detection (DAD) tries o.set_ipv6_dad_messages(openvpn['ipv6_dup_addr_detect']) # IPv6 EUI-based addresses - only in TAP mode (TUN's have no MAC) # If MAC has changed, old EUI64 addresses won't get deleted, # but this isn't easy to solve, so leave them. # This is even more difficult as openvpn uses a random MAC for the # initial interface creation, unless set by 'lladdr'. # NOTE: right now the interface is always deleted. For future # compatibility when tap's are not deleted, leave the del_ in if openvpn['mode'] == 'tap': for addr in openvpn['ipv6_eui64_prefix_remove']: o.del_ipv6_eui64_address(addr) for addr in openvpn['ipv6_eui64_prefix']: o.add_ipv6_eui64_address(addr) except: pass # TAP interface needs to be brought up explicitly if openvpn['type'] == 'tap': if not openvpn['disable']: VTunIf(interface).set_admin_state('up') return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)