diff --git a/python/vyos/utils/network.py b/python/vyos/utils/network.py index b58e02d91..63c9e263d 100644 --- a/python/vyos/utils/network.py +++ b/python/vyos/utils/network.py @@ -1,545 +1,545 @@ # Copyright 2023 VyOS maintainers and contributors <maintainers@vyos.io> # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public # License as published by the Free Software Foundation; either # version 2.1 of the License, or (at your option) any later version. # # This library 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 # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public # License along with this library. If not, see <http://www.gnu.org/licenses/>. def _are_same_ip(one, two): from socket import AF_INET from socket import AF_INET6 from socket import inet_pton from vyos.template import is_ipv4 # compare the binary representation of the IP f_one = AF_INET if is_ipv4(one) else AF_INET6 s_two = AF_INET if is_ipv4(two) else AF_INET6 return inet_pton(f_one, one) == inet_pton(f_one, two) def get_protocol_by_name(protocol_name): """Get protocol number by protocol name % get_protocol_by_name('tcp') % 6 """ import socket try: protocol_number = socket.getprotobyname(protocol_name) return protocol_number except socket.error: return protocol_name def interface_exists(interface) -> bool: import os return os.path.exists(f'/sys/class/net/{interface}') def interface_exists_in_netns(interface_name, netns): from vyos.utils.process import rc_cmd rc, out = rc_cmd(f'ip netns exec {netns} ip link show dev {interface_name}') if rc == 0: return True return False def get_vrf_members(vrf: str) -> list: """ Get list of interface VRF members :param vrf: str :return: list """ import json from vyos.utils.process import cmd interfaces = [] try: if not interface_exists(vrf): raise ValueError(f'VRF "{vrf}" does not exist!') output = cmd(f'ip --json --brief link show vrf {vrf}') answer = json.loads(output) for data in answer: if 'ifname' in data: interfaces.append(data.get('ifname')) except: pass return interfaces def get_interface_vrf(interface): """ Returns VRF of given interface """ from vyos.utils.dict import dict_search from vyos.utils.network import get_interface_config tmp = get_interface_config(interface) if dict_search('linkinfo.info_slave_kind', tmp) == 'vrf': return tmp['master'] return 'default' def get_interface_config(interface): """ Returns the used encapsulation protocol for given interface. If interface does not exist, None is returned. """ import os if not os.path.exists(f'/sys/class/net/{interface}'): return None from json import loads from vyos.utils.process import cmd tmp = loads(cmd(f'ip --detail --json link show dev {interface}'))[0] return tmp def get_interface_address(interface): """ Returns the used encapsulation protocol for given interface. If interface does not exist, None is returned. """ import os if not os.path.exists(f'/sys/class/net/{interface}'): return None from json import loads from vyos.utils.process import cmd tmp = loads(cmd(f'ip --detail --json addr show dev {interface}'))[0] return tmp def get_interface_namespace(iface): """ Returns wich netns the interface belongs to """ from json import loads from vyos.utils.process import cmd # Check if netns exist tmp = loads(cmd(f'ip --json netns ls')) if len(tmp) == 0: return None for ns in tmp: netns = f'{ns["name"]}' # Search interface in each netns data = loads(cmd(f'ip netns exec {netns} ip --json link show')) for tmp in data: if iface == tmp["ifname"]: return netns def is_ipv6_tentative(iface: str, ipv6_address: str) -> bool: """Check if IPv6 address is in tentative state. This function checks if an IPv6 address on a specific network interface is in the tentative state. IPv6 tentative addresses are not fully configured and are undergoing Duplicate Address Detection (DAD) to ensure they are unique on the network. Args: iface (str): The name of the network interface. ipv6_address (str): The IPv6 address to check. Returns: bool: True if the IPv6 address is tentative, False otherwise. """ import json from vyos.utils.process import rc_cmd rc, out = rc_cmd(f'ip -6 --json address show dev {iface}') if rc: return False data = json.loads(out) for addr_info in data[0]['addr_info']: if ( addr_info.get('local') == ipv6_address and addr_info.get('tentative', False) ): return True return False def is_wwan_connected(interface): """ Determine if a given WWAN interface, e.g. wwan0 is connected to the carrier network or not """ import json from vyos.utils.dict import dict_search from vyos.utils.process import cmd from vyos.utils.process import is_systemd_service_active if not interface.startswith('wwan'): raise ValueError(f'Specified interface "{interface}" is not a WWAN interface') # ModemManager is required for connection(s) - if service is not running, # there won't be any connection at all! if not is_systemd_service_active('ModemManager.service'): return False modem = interface.lstrip('wwan') tmp = cmd(f'mmcli --modem {modem} --output-json') tmp = json.loads(tmp) # return True/False if interface is in connected state return dict_search('modem.generic.state', tmp) == 'connected' def get_bridge_fdb(interface): """ Returns the forwarding database entries for a given interface """ import os if not os.path.exists(f'/sys/class/net/{interface}'): return None from json import loads from vyos.utils.process import cmd tmp = loads(cmd(f'bridge -j fdb show dev {interface}')) return tmp def get_all_vrfs(): """ Return a dictionary of all system wide known VRF instances """ from json import loads from vyos.utils.process import cmd tmp = loads(cmd('ip --json vrf list')) # Result is of type [{"name":"red","table":1000},{"name":"blue","table":2000}] # so we will re-arrange it to a more nicer representation: # {'red': {'table': 1000}, 'blue': {'table': 2000}} data = {} for entry in tmp: name = entry.pop('name') data[name] = entry return data def interface_list() -> list: from vyos.ifconfig import Section """ Get list of interfaces in system :rtype: list """ return Section.interfaces() def vrf_list() -> list: """ Get list of VRFs in system :rtype: list """ return list(get_all_vrfs().keys()) def mac2eui64(mac, prefix=None): """ Convert a MAC address to a EUI64 address or, with prefix provided, a full IPv6 address. Thankfully copied from https://gist.github.com/wido/f5e32576bb57b5cc6f934e177a37a0d3 """ import re from ipaddress import ip_network # http://tools.ietf.org/html/rfc4291#section-2.5.1 eui64 = re.sub(r'[.:-]', '', mac).lower() eui64 = eui64[0:6] + 'fffe' + eui64[6:] eui64 = hex(int(eui64[0:2], 16) ^ 2)[2:].zfill(2) + eui64[2:] if prefix is None: return ':'.join(re.findall(r'.{4}', eui64)) else: try: net = ip_network(prefix, strict=False) euil = int('0x{0}'.format(eui64), 16) return str(net[euil]) except: # pylint: disable=bare-except return def check_port_availability(ipaddress, port, protocol): """ Check if port is available and not used by any service Return False if a port is busy or IP address does not exists Should be used carefully for services that can start listening dynamically, because IP address may be dynamic too """ from socketserver import TCPServer, UDPServer from ipaddress import ip_address # verify arguments try: ipaddress = ip_address(ipaddress).compressed except: raise ValueError(f'The {ipaddress} is not a valid IPv4 or IPv6 address') if port not in range(1, 65536): raise ValueError(f'The port number {port} is not in the 1-65535 range') if protocol not in ['tcp', 'udp']: raise ValueError(f'The protocol {protocol} is not supported. Only tcp and udp are allowed') # check port availability try: if protocol == 'tcp': server = TCPServer((ipaddress, port), None, bind_and_activate=True) if protocol == 'udp': server = UDPServer((ipaddress, port), None, bind_and_activate=True) server.server_close() except Exception as e: # errno.h: #define EADDRINUSE 98 /* Address already in use */ if e.errno == 98: return False return True def is_listen_port_bind_service(port: int, service: str) -> bool: """Check if listen port bound to expected program name :param port: Bind port :param service: Program name :return: bool Example: % is_listen_port_bind_service(443, 'nginx') True % is_listen_port_bind_service(443, 'ocserv-main') False """ from psutil import net_connections as connections from psutil import Process as process for connection in connections(): addr = connection.laddr pid = connection.pid pid_name = process(pid).name() pid_port = addr.port if service == pid_name and port == pid_port: return True return False def is_ipv6_link_local(addr): """ Check if addrsss is an IPv6 link-local address. Returns True/False """ from ipaddress import ip_interface from vyos.template import is_ipv6 addr = addr.split('%')[0] if is_ipv6(addr): if ip_interface(addr).is_link_local: return True return False -def is_addr_assigned(ip_address, vrf=None) -> bool: +def is_addr_assigned(ip_address, vrf=None, include_vrf=False) -> bool: """ Verify if the given IPv4/IPv6 address is assigned to any interface """ from netifaces import interfaces from vyos.utils.network import get_interface_config from vyos.utils.dict import dict_search for interface in interfaces(): # Check if interface belongs to the requested VRF, if this is not the # case there is no need to proceed with this data set - continue loop # with next element tmp = get_interface_config(interface) - if dict_search('master', tmp) != vrf: + if dict_search('master', tmp) != vrf and not include_vrf: continue if is_intf_addr_assigned(interface, ip_address): return True return False def is_intf_addr_assigned(intf, address) -> bool: """ Verify if the given IPv4/IPv6 address is assigned to specific interface. It can check both a single IP address (e.g. 192.0.2.1 or a assigned CIDR address 192.0.2.1/24. """ from vyos.template import is_ipv4 from netifaces import ifaddresses from netifaces import AF_INET from netifaces import AF_INET6 # check if the requested address type is configured at all # { # 17: [{'addr': '08:00:27:d9:5b:04', 'broadcast': 'ff:ff:ff:ff:ff:ff'}], # 2: [{'addr': '10.0.2.15', 'netmask': '255.255.255.0', 'broadcast': '10.0.2.255'}], # 10: [{'addr': 'fe80::a00:27ff:fed9:5b04%eth0', 'netmask': 'ffff:ffff:ffff:ffff::'}] # } try: addresses = ifaddresses(intf) except ValueError as e: print(e) return False # determine IP version (AF_INET or AF_INET6) depending on passed address addr_type = AF_INET if is_ipv4(address) else AF_INET6 # Check every IP address on this interface for a match netmask = None if '/' in address: address, netmask = address.split('/') for ip in addresses.get(addr_type, []): # ip can have the interface name in the 'addr' field, we need to remove it # {'addr': 'fe80::a00:27ff:fec5:f821%eth2', 'netmask': 'ffff:ffff:ffff:ffff::'} ip_addr = ip['addr'].split('%')[0] if not _are_same_ip(address, ip_addr): continue # we do not have a netmask to compare against, they are the same if not netmask: return True prefixlen = '' if is_ipv4(ip_addr): prefixlen = sum([bin(int(_)).count('1') for _ in ip['netmask'].split('.')]) else: prefixlen = sum([bin(int(_,16)).count('1') for _ in ip['netmask'].split('/')[0].split(':') if _]) if str(prefixlen) == netmask: return True return False def is_loopback_addr(addr): """ Check if supplied IPv4/IPv6 address is a loopback address """ from ipaddress import ip_address return ip_address(addr).is_loopback def is_wireguard_key_pair(private_key: str, public_key:str) -> bool: """ Checks if public/private keys are keypair :param private_key: Wireguard private key :type private_key: str :param public_key: Wireguard public key :type public_key: str :return: If public/private keys are keypair returns True else False :rtype: bool """ from vyos.utils.process import cmd gen_public_key = cmd('wg pubkey', input=private_key) if gen_public_key == public_key: return True else: return False def is_subnet_connected(subnet, primary=False): """ Verify is the given IPv4/IPv6 subnet is connected to any interface on this system. primary check if the subnet is reachable via the primary IP address of this interface, or in other words has a broadcast address configured. ISC DHCP for instance will complain if it should listen on non broadcast interfaces. Return True/False """ from ipaddress import ip_address from ipaddress import ip_network from netifaces import ifaddresses from netifaces import interfaces from netifaces import AF_INET from netifaces import AF_INET6 from vyos.template import is_ipv6 # determine IP version (AF_INET or AF_INET6) depending on passed address addr_type = AF_INET if is_ipv6(subnet): addr_type = AF_INET6 for interface in interfaces(): # check if the requested address type is configured at all if addr_type not in ifaddresses(interface).keys(): continue # An interface can have multiple addresses, but some software components # only support the primary address :( if primary: ip = ifaddresses(interface)[addr_type][0]['addr'] if ip_address(ip) in ip_network(subnet): return True else: # Check every assigned IP address if it is connected to the subnet # in question for ip in ifaddresses(interface)[addr_type]: # remove interface extension (e.g. %eth0) that gets thrown on the end of _some_ addrs addr = ip['addr'].split('%')[0] if ip_address(addr) in ip_network(subnet): return True return False def is_afi_configured(interface: str, afi): """ Check if given address family is configured, or in other words - an IP address is assigned to the interface. """ from netifaces import ifaddresses from netifaces import AF_INET from netifaces import AF_INET6 if afi not in [AF_INET, AF_INET6]: raise ValueError('Address family must be in [AF_INET, AF_INET6]') try: addresses = ifaddresses(interface) except ValueError as e: print(e) return False return afi in addresses def get_vxlan_vlan_tunnels(interface: str) -> list: """ Return a list of strings with VLAN IDs configured in the Kernel """ from json import loads from vyos.utils.process import cmd if not interface.startswith('vxlan'): raise ValueError('Only applicable for VXLAN interfaces!') # Determine current OS Kernel configured VLANs # # $ bridge -j -p vlan tunnelshow dev vxlan0 # [ { # "ifname": "vxlan0", # "tunnels": [ { # "vlan": 10, # "vlanEnd": 11, # "tunid": 10010, # "tunidEnd": 10011 # },{ # "vlan": 20, # "tunid": 10020 # } ] # } ] # os_configured_vlan_ids = [] tmp = loads(cmd(f'bridge --json vlan tunnelshow dev {interface}')) if tmp: for tunnel in tmp[0].get('tunnels', {}): vlanStart = tunnel['vlan'] if 'vlanEnd' in tunnel: vlanEnd = tunnel['vlanEnd'] # Build a real list for user VLAN IDs vlan_list = list(range(vlanStart, vlanEnd +1)) # Convert list of integers to list or strings os_configured_vlan_ids.extend(map(str, vlan_list)) # Proceed with next tunnel - this one is complete continue # Add single tunel id - not part of a range os_configured_vlan_ids.append(str(vlanStart)) return os_configured_vlan_ids def get_vxlan_vni_filter(interface: str) -> list: """ Return a list of strings with VNIs configured in the Kernel""" from json import loads from vyos.utils.process import cmd if not interface.startswith('vxlan'): raise ValueError('Only applicable for VXLAN interfaces!') # Determine current OS Kernel configured VNI filters in VXLAN interface # # $ bridge -j vni show dev vxlan1 # [{"ifname":"vxlan1","vnis":[{"vni":100},{"vni":200},{"vni":300,"vniEnd":399}]}] # # Example output: ['10010', '10020', '10021', '10022'] os_configured_vnis = [] tmp = loads(cmd(f'bridge --json vni show dev {interface}')) if tmp: for tunnel in tmp[0].get('vnis', {}): vniStart = tunnel['vni'] if 'vniEnd' in tunnel: vniEnd = tunnel['vniEnd'] # Build a real list for user VNIs vni_list = list(range(vniStart, vniEnd +1)) # Convert list of integers to list or strings os_configured_vnis.extend(map(str, vni_list)) # Proceed with next tunnel - this one is complete continue # Add single tunel id - not part of a range os_configured_vnis.append(str(vniStart)) return os_configured_vnis diff --git a/smoketest/scripts/cli/test_service_dhcp-server.py b/smoketest/scripts/cli/test_service_dhcp-server.py index 24ae2f4e2..3d1f47ece 100755 --- a/smoketest/scripts/cli/test_service_dhcp-server.py +++ b/smoketest/scripts/cli/test_service_dhcp-server.py @@ -1,505 +1,527 @@ #!/usr/bin/env python3 # # Copyright (C) 2020-2024 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 <http://www.gnu.org/licenses/>. import unittest from base_vyostest_shim import VyOSUnitTestSHIM from vyos.configsession import ConfigSessionError from vyos.utils.process import process_named_running from vyos.utils.file import read_file from vyos.template import address_from_cidr from vyos.template import inc_ip from vyos.template import dec_ip from vyos.template import netmask_from_cidr PROCESS_NAME = 'dhcpd' DHCPD_CONF = '/run/dhcp-server/dhcpd.conf' base_path = ['service', 'dhcp-server'] subnet = '192.0.2.0/25' router = inc_ip(subnet, 1) dns_1 = inc_ip(subnet, 2) dns_2 = inc_ip(subnet, 3) domain_name = 'vyos.net' class TestServiceDHCPServer(VyOSUnitTestSHIM.TestCase): @classmethod def setUpClass(cls): super(TestServiceDHCPServer, cls).setUpClass() cidr_mask = subnet.split('/')[-1] cls.cli_set(cls, ['interfaces', 'dummy', 'dum8765', 'address', f'{router}/{cidr_mask}']) @classmethod def tearDownClass(cls): cls.cli_delete(cls, ['interfaces', 'dummy', 'dum8765']) super(TestServiceDHCPServer, cls).tearDownClass() def tearDown(self): self.cli_delete(base_path) self.cli_commit() def test_dhcp_single_pool_range(self): shared_net_name = 'SMOKE-1' range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 20) range_1_start = inc_ip(subnet, 40) range_1_stop = inc_ip(subnet, 50) self.cli_set(base_path + ['dynamic-dns-update']) pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet] # we use the first subnet IP address as default gateway self.cli_set(pool + ['default-router', router]) self.cli_set(pool + ['name-server', dns_1]) self.cli_set(pool + ['name-server', dns_2]) self.cli_set(pool + ['domain-name', domain_name]) self.cli_set(pool + ['ping-check']) # check validate() - No DHCP address range or active static-mapping set with self.assertRaises(ConfigSessionError): self.cli_commit() self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) self.cli_set(pool + ['range', '1', 'start', range_1_start]) self.cli_set(pool + ['range', '1', 'stop', range_1_stop]) # commit changes self.cli_commit() config = read_file(DHCPD_CONF) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) self.assertIn(f'ddns-update-style interim;', config) self.assertIn(f'subnet {network} netmask {netmask}' + r' {', config) self.assertIn(f'option domain-name-servers {dns_1}, {dns_2};', config) self.assertIn(f'option routers {router};', config) self.assertIn(f'option domain-name "{domain_name}";', config) self.assertIn(f'default-lease-time 86400;', config) self.assertIn(f'max-lease-time 86400;', config) self.assertIn(f'ping-check true;', config) self.assertIn(f'range {range_0_start} {range_0_stop};', config) self.assertIn(f'range {range_1_start} {range_1_stop};', config) self.assertIn(f'set shared-networkname = "{shared_net_name}";', config) # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_single_pool_options(self): shared_net_name = 'SMOKE-0815' range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 20) smtp_server = '1.2.3.4' time_server = '4.3.2.1' tftp_server = 'tftp.vyos.io' search_domains = ['foo.vyos.net', 'bar.vyos.net'] bootfile_name = 'vyos' bootfile_server = '192.0.2.1' wpad = 'http://wpad.vyos.io/foo/bar' server_identifier = bootfile_server ipv6_only_preferred = '300' pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet] # we use the first subnet IP address as default gateway self.cli_set(pool + ['default-router', router]) self.cli_set(pool + ['name-server', dns_1]) self.cli_set(pool + ['name-server', dns_2]) self.cli_set(pool + ['domain-name', domain_name]) self.cli_set(pool + ['ip-forwarding']) self.cli_set(pool + ['smtp-server', smtp_server]) self.cli_set(pool + ['pop-server', smtp_server]) self.cli_set(pool + ['time-server', time_server]) self.cli_set(pool + ['tftp-server-name', tftp_server]) for search in search_domains: self.cli_set(pool + ['domain-search', search]) self.cli_set(pool + ['bootfile-name', bootfile_name]) self.cli_set(pool + ['bootfile-server', bootfile_server]) self.cli_set(pool + ['wpad-url', wpad]) self.cli_set(pool + ['server-identifier', server_identifier]) self.cli_set(pool + ['static-route', '10.0.0.0/24', 'next-hop', '192.0.2.1']) self.cli_set(pool + ['ipv6-only-preferred', ipv6_only_preferred]) # check validate() - No DHCP address range or active static-mapping set with self.assertRaises(ConfigSessionError): self.cli_commit() self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) # commit changes self.cli_commit() config = read_file(DHCPD_CONF) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) self.assertIn(f'ddns-update-style none;', config) self.assertIn(f'subnet {network} netmask {netmask}' + r' {', config) self.assertIn(f'option domain-name-servers {dns_1}, {dns_2};', config) self.assertIn(f'option routers {router};', config) self.assertIn(f'option domain-name "{domain_name}";', config) search = '"' + ('", "').join(search_domains) + '"' self.assertIn(f'option domain-search {search};', config) self.assertIn(f'option ip-forwarding true;', config) self.assertIn(f'option smtp-server {smtp_server};', config) self.assertIn(f'option pop-server {smtp_server};', config) self.assertIn(f'option time-servers {time_server};', config) self.assertIn(f'option wpad-url "{wpad}";', config) self.assertIn(f'option dhcp-server-identifier {server_identifier};', config) self.assertIn(f'option tftp-server-name "{tftp_server}";', config) self.assertIn(f'option bootfile-name "{bootfile_name}";', config) self.assertIn(f'filename "{bootfile_name}";', config) self.assertIn(f'next-server {bootfile_server};', config) self.assertIn(f'default-lease-time 86400;', config) self.assertIn(f'max-lease-time 86400;', config) self.assertIn(f'range {range_0_start} {range_0_stop};', config) self.assertIn(f'set shared-networkname = "{shared_net_name}";', config) self.assertIn(f'option rfc8925-ipv6-only-preferred {ipv6_only_preferred};', config) # weird syntax for those static routes self.assertIn(f'option rfc3442-static-route 24,10,0,0,192,0,2,1, 0,192,0,2,1;', config) self.assertIn(f'option windows-static-route 24,10,0,0,192,0,2,1;', config) # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_single_pool_static_mapping(self): shared_net_name = 'SMOKE-2' domain_name = 'private' pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet] # we use the first subnet IP address as default gateway self.cli_set(pool + ['default-router', router]) self.cli_set(pool + ['name-server', dns_1]) self.cli_set(pool + ['name-server', dns_2]) self.cli_set(pool + ['domain-name', domain_name]) # check validate() - No DHCP address range or active static-mapping set with self.assertRaises(ConfigSessionError): self.cli_commit() client_base = 10 for client in ['client1', 'client2', 'client3']: mac = '00:50:00:00:00:{}'.format(client_base) self.cli_set(pool + ['static-mapping', client, 'mac-address', mac]) self.cli_set(pool + ['static-mapping', client, 'ip-address', inc_ip(subnet, client_base)]) client_base += 1 # cannot have mappings with duplicate IP addresses self.cli_set(pool + ['static-mapping', 'dupe1', 'mac-address', '00:50:00:00:fe:ff']) self.cli_set(pool + ['static-mapping', 'dupe1', 'ip-address', inc_ip(subnet, 10)]) with self.assertRaises(ConfigSessionError): self.cli_commit() self.cli_set(pool + ['static-mapping', 'dupe1', 'disable']) self.cli_commit() self.cli_delete(pool + ['static-mapping', 'dupe1']) # cannot have mappings with duplicate MAC addresses self.cli_set(pool + ['static-mapping', 'dupe2', 'mac-address', '00:50:00:00:00:10']) self.cli_set(pool + ['static-mapping', 'dupe2', 'ip-address', inc_ip(subnet, 120)]) with self.assertRaises(ConfigSessionError): self.cli_commit() self.cli_delete(pool + ['static-mapping', 'dupe2']) # commit changes self.cli_commit() config = read_file(DHCPD_CONF) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) self.assertIn(f'ddns-update-style none;', config) self.assertIn(f'subnet {network} netmask {netmask}' + r' {', config) self.assertIn(f'option domain-name-servers {dns_1}, {dns_2};', config) self.assertIn(f'option routers {router};', config) self.assertIn(f'option domain-name "{domain_name}";', config) self.assertIn(f'default-lease-time 86400;', config) self.assertIn(f'max-lease-time 86400;', config) client_base = 10 for client in ['client1', 'client2', 'client3']: mac = '00:50:00:00:00:{}'.format(client_base) ip = inc_ip(subnet, client_base) self.assertIn(f'host {shared_net_name}_{client}' + ' {', config) self.assertIn(f'fixed-address {ip};', config) self.assertIn(f'hardware ethernet {mac};', config) client_base += 1 self.assertIn(f'set shared-networkname = "{shared_net_name}";', config) # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_multiple_pools(self): lease_time = '14400' for network in ['0', '1', '2', '3']: shared_net_name = f'VyOS-SMOKETEST-{network}' subnet = f'192.0.{network}.0/24' router = inc_ip(subnet, 1) dns_1 = inc_ip(subnet, 2) range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 20) range_1_start = inc_ip(subnet, 30) range_1_stop = inc_ip(subnet, 40) pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet] # we use the first subnet IP address as default gateway self.cli_set(pool + ['default-router', router]) self.cli_set(pool + ['name-server', dns_1]) self.cli_set(pool + ['domain-name', domain_name]) self.cli_set(pool + ['lease', lease_time]) self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) self.cli_set(pool + ['range', '1', 'start', range_1_start]) self.cli_set(pool + ['range', '1', 'stop', range_1_stop]) client_base = 60 for client in ['client1', 'client2', 'client3', 'client4']: mac = '02:50:00:00:00:{}'.format(client_base) self.cli_set(pool + ['static-mapping', client, 'mac-address', mac]) self.cli_set(pool + ['static-mapping', client, 'ip-address', inc_ip(subnet, client_base)]) client_base += 1 # commit changes self.cli_commit() config = read_file(DHCPD_CONF) for network in ['0', '1', '2', '3']: shared_net_name = f'VyOS-SMOKETEST-{network}' subnet = f'192.0.{network}.0/24' router = inc_ip(subnet, 1) dns_1 = inc_ip(subnet, 2) range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 20) range_1_start = inc_ip(subnet, 30) range_1_stop = inc_ip(subnet, 40) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) self.assertIn(f'ddns-update-style none;', config) self.assertIn(f'subnet {network} netmask {netmask}' + r' {', config) self.assertIn(f'option domain-name-servers {dns_1};', config) self.assertIn(f'option routers {router};', config) self.assertIn(f'option domain-name "{domain_name}";', config) self.assertIn(f'default-lease-time {lease_time};', config) self.assertIn(f'max-lease-time {lease_time};', config) self.assertIn(f'range {range_0_start} {range_0_stop};', config) self.assertIn(f'range {range_1_start} {range_1_stop};', config) self.assertIn(f'set shared-networkname = "{shared_net_name}";', config) client_base = 60 for client in ['client1', 'client2', 'client3', 'client4']: mac = '02:50:00:00:00:{}'.format(client_base) ip = inc_ip(subnet, client_base) self.assertIn(f'host {shared_net_name}_{client}' + ' {', config) self.assertIn(f'fixed-address {ip};', config) self.assertIn(f'hardware ethernet {mac};', config) client_base += 1 # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_exclude_not_in_range(self): # T3180: verify else path when slicing DHCP ranges and exclude address # is not part of the DHCP range range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 20) pool = base_path + ['shared-network-name', 'EXCLUDE-TEST', 'subnet', subnet] self.cli_set(pool + ['default-router', router]) self.cli_set(pool + ['exclude', router]) self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) # commit changes self.cli_commit() # VErify config = read_file(DHCPD_CONF) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) self.assertIn(f'subnet {network} netmask {netmask}' + r' {', config) self.assertIn(f'option routers {router};', config) self.assertIn(f'range {range_0_start} {range_0_stop};', config) # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_exclude_in_range(self): # T3180: verify else path when slicing DHCP ranges and exclude address # is not part of the DHCP range range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 100) # the DHCP exclude addresse is blanked out of the range which is done # by slicing one range into two ranges exclude_addr = inc_ip(range_0_start, 20) range_0_stop_excl = dec_ip(exclude_addr, 1) range_0_start_excl = inc_ip(exclude_addr, 1) pool = base_path + ['shared-network-name', 'EXCLUDE-TEST-2', 'subnet', subnet] self.cli_set(pool + ['default-router', router]) self.cli_set(pool + ['exclude', exclude_addr]) self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) # commit changes self.cli_commit() # Verify config = read_file(DHCPD_CONF) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) self.assertIn(f'subnet {network} netmask {netmask}' + r' {', config) self.assertIn(f'option routers {router};', config) self.assertIn(f'range {range_0_start} {range_0_stop_excl};', config) self.assertIn(f'range {range_0_start_excl} {range_0_stop};', config) # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_relay_server(self): # Listen on specific address and return DHCP leases from a non # directly connected pool self.cli_set(base_path + ['listen-address', router]) relay_subnet = '10.0.0.0/16' relay_router = inc_ip(relay_subnet, 1) range_0_start = '10.0.1.0' range_0_stop = '10.0.250.255' pool = base_path + ['shared-network-name', 'RELAY', 'subnet', relay_subnet] self.cli_set(pool + ['default-router', relay_router]) self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) # commit changes self.cli_commit() config = read_file(DHCPD_CONF) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) # Check the relay network self.assertIn(f'subnet {network} netmask {netmask}' + r' { }', config) relay_network = address_from_cidr(relay_subnet) relay_netmask = netmask_from_cidr(relay_subnet) self.assertIn(f'subnet {relay_network} netmask {relay_netmask}' + r' {', config) self.assertIn(f'option routers {relay_router};', config) self.assertIn(f'range {range_0_start} {range_0_stop};', config) # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_invalid_raw_options(self): shared_net_name = 'SMOKE-5' range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 20) pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet] # we use the first subnet IP address as default gateway self.cli_set(pool + ['default-router', router]) self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) self.cli_set(base_path + ['global-parameters', 'this-is-crap']) # check generate() - dhcpd should not acceot this garbage config with self.assertRaises(ConfigSessionError): self.cli_commit() self.cli_delete(base_path + ['global-parameters']) # commit changes self.cli_commit() # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) def test_dhcp_failover(self): shared_net_name = 'FAILOVER' failover_name = 'VyOS-Failover' range_0_start = inc_ip(subnet, 10) range_0_stop = inc_ip(subnet, 20) pool = base_path + ['shared-network-name', shared_net_name, 'subnet', subnet] # we use the first subnet IP address as default gateway self.cli_set(pool + ['default-router', router]) # check validate() - No DHCP address range or active static-mapping set with self.assertRaises(ConfigSessionError): self.cli_commit() self.cli_set(pool + ['range', '0', 'start', range_0_start]) self.cli_set(pool + ['range', '0', 'stop', range_0_stop]) # failover failover_local = router failover_remote = inc_ip(router, 1) self.cli_set(base_path + ['failover', 'source-address', failover_local]) self.cli_set(base_path + ['failover', 'name', failover_name]) self.cli_set(base_path + ['failover', 'remote', failover_remote]) self.cli_set(base_path + ['failover', 'status', 'primary']) # check validate() - failover needs to be enabled for at least one subnet with self.assertRaises(ConfigSessionError): self.cli_commit() self.cli_set(pool + ['enable-failover']) # commit changes self.cli_commit() config = read_file(DHCPD_CONF) self.assertIn(f'failover peer "{failover_name}"' + r' {', config) self.assertIn(f'primary;', config) self.assertIn(f'mclt 1800;', config) self.assertIn(f'mclt 1800;', config) self.assertIn(f'split 128;', config) self.assertIn(f'port 647;', config) self.assertIn(f'peer port 647;', config) self.assertIn(f'max-response-delay 30;', config) self.assertIn(f'max-unacked-updates 10;', config) self.assertIn(f'load balance max seconds 3;', config) self.assertIn(f'address {failover_local};', config) self.assertIn(f'peer address {failover_remote};', config) network = address_from_cidr(subnet) netmask = netmask_from_cidr(subnet) self.assertIn(f'ddns-update-style none;', config) self.assertIn(f'subnet {network} netmask {netmask}' + r' {', config) self.assertIn(f'option routers {router};', config) self.assertIn(f'range {range_0_start} {range_0_stop};', config) self.assertIn(f'set shared-networkname = "{shared_net_name}";', config) self.assertIn(f'failover peer "{failover_name}";', config) self.assertIn(f'deny dynamic bootp clients;', config) # Check for running process self.assertTrue(process_named_running(PROCESS_NAME)) + def test_dhcp_on_interface_with_vrf(self): + self.cli_set(['interfaces', 'ethernet', 'eth1', 'address', '10.1.1.1/30']) + self.cli_set(['interfaces', 'ethernet', 'eth1', 'vrf', 'SMOKE-DHCP']) + self.cli_set(['protocols', 'static', 'route', '10.1.10.0/24', 'interface', 'eth1', 'vrf', 'SMOKE-DHCP']) + self.cli_set(['vrf', 'name', 'SMOKE-DHCP', 'protocols', 'static', 'route', '10.1.10.0/24', 'next-hop', '10.1.1.2']) + self.cli_set(['vrf', 'name', 'SMOKE-DHCP', 'table', '1000']) + self.cli_set(base_path + ['shared-network-name', 'SMOKE-DHCP-NETWORK', 'subnet', '10.1.10.0/24', 'default-router', '10.1.10.1']) + self.cli_set(base_path + ['shared-network-name', 'SMOKE-DHCP-NETWORK', 'subnet', '10.1.10.0/24', 'name-server', '1.1.1.1']) + self.cli_set(base_path + ['shared-network-name', 'SMOKE-DHCP-NETWORK', 'subnet', '10.1.10.0/24', 'range', '1', 'start', '10.1.10.10']) + self.cli_set(base_path + ['shared-network-name', 'SMOKE-DHCP-NETWORK', 'subnet', '10.1.10.0/24', 'range', '1', 'stop', '10.1.10.20']) + self.cli_set(base_path + ['listen-address', '10.1.1.1']) + self.cli_commit() + + config = read_file(DHCPD_CONF) + self.assertIn('subnet 10.1.1.0 netmask 255.255.255.252', config) + + self.cli_delete(['interfaces', 'ethernet', 'eth1', 'vrf', 'SMOKE-DHCP']) + self.cli_delete(['protocols', 'static', 'route', '10.1.10.0/24', 'interface', 'eth1', 'vrf']) + self.cli_delete(['vrf', 'name', 'SMOKE-DHCP']) + self.cli_commit() + + if __name__ == '__main__': unittest.main(verbosity=2) diff --git a/src/conf_mode/service_dhcp-server.py b/src/conf_mode/service_dhcp-server.py index 90056887a..e910ecdf7 100755 --- a/src/conf_mode/service_dhcp-server.py +++ b/src/conf_mode/service_dhcp-server.py @@ -1,350 +1,349 @@ #!/usr/bin/env python3 # # Copyright (C) 2018-2024 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 <http://www.gnu.org/licenses/>. import os from ipaddress import ip_address from ipaddress import ip_network from netaddr import IPAddress from netaddr import IPRange from sys import exit from vyos.base import DeprecationWarning from vyos.config import Config from vyos.template import render from vyos.utils.dict import dict_search from vyos.utils.process import call from vyos.utils.process import run from vyos.utils.network import is_subnet_connected from vyos.utils.network import is_addr_assigned from vyos import ConfigError from vyos import airbag airbag.enable() config_file = '/run/dhcp-server/dhcpd.conf' systemd_override = r'/run/systemd/system/isc-dhcp-server.service.d/10-override.conf' def dhcp_slice_range(exclude_list, range_dict): """ This function is intended to slice a DHCP range. What does it mean? Lets assume we have a DHCP range from '192.0.2.1' to '192.0.2.100' but want to exclude address '192.0.2.74' and '192.0.2.75'. We will pass an input 'range_dict' in the format: {'start' : '192.0.2.1', 'stop' : '192.0.2.100' } and we will receive an output list of: [{'start' : '192.0.2.1' , 'stop' : '192.0.2.73' }, {'start' : '192.0.2.76', 'stop' : '192.0.2.100' }] The resulting list can then be used in turn to build the proper dhcpd configuration file. """ output = [] # exclude list must be sorted for this to work exclude_list = sorted(exclude_list) range_start = range_dict['start'] range_stop = range_dict['stop'] range_last_exclude = '' for e in exclude_list: if (ip_address(e) >= ip_address(range_start)) and \ (ip_address(e) <= ip_address(range_stop)): range_last_exclude = e for e in exclude_list: if (ip_address(e) >= ip_address(range_start)) and \ (ip_address(e) <= ip_address(range_stop)): # Build new address range ending one address before exclude address r = { 'start' : range_start, 'stop' : str(ip_address(e) -1) } # On the next run our address range will start one address after # the exclude address range_start = str(ip_address(e) + 1) # on subsequent exclude addresses we can not # append them to our output if not (ip_address(r['start']) > ip_address(r['stop'])): # Everything is fine, add range to result output.append(r) # Take care of last IP address range spanning from the last exclude # address (+1) to the end of the initial configured range if ip_address(e) == ip_address(range_last_exclude): r = { 'start': str(ip_address(e) + 1), 'stop': str(range_stop) } if not (ip_address(r['start']) > ip_address(r['stop'])): output.append(r) else: # if the excluded address was not part of the range, we simply return # the entire ranga again if not range_last_exclude: if range_dict not in output: output.append(range_dict) return output def get_config(config=None): if config: conf = config else: conf = Config() base = ['service', 'dhcp-server'] if not conf.exists(base): return None dhcp = conf.get_config_dict(base, key_mangling=('-', '_'), no_tag_node_value_mangle=True, get_first_key=True, with_recursive_defaults=True) if 'shared_network_name' in dhcp: for network, network_config in dhcp['shared_network_name'].items(): if 'subnet' in network_config: for subnet, subnet_config in network_config['subnet'].items(): # If exclude IP addresses are defined we need to slice them out of # the defined ranges if {'exclude', 'range'} <= set(subnet_config): new_range_id = 0 new_range_dict = {} for r, r_config in subnet_config['range'].items(): for slice in dhcp_slice_range(subnet_config['exclude'], r_config): new_range_dict.update({new_range_id : slice}) new_range_id +=1 dhcp['shared_network_name'][network]['subnet'][subnet].update( {'range' : new_range_dict}) return dhcp def verify(dhcp): # bail out early - looks like removal from running config if not dhcp or 'disable' in dhcp: return None # If DHCP is enabled we need one share-network if 'shared_network_name' not in dhcp: raise ConfigError('No DHCP shared networks configured.\n' \ 'At least one DHCP shared network must be configured.') # Inspect shared-network/subnet listen_ok = False subnets = [] failover_ok = False shared_networks = len(dhcp['shared_network_name']) disabled_shared_networks = 0 common_deprecation_msg = 'are subject of removal in VyOS 1.5! Please raise a feature request for proper CLI nodes!' if 'global_parameters' in dhcp: DeprecationWarning(f'Additional global parameters {common_deprecation_msg}') # A shared-network requires a subnet definition for network, network_config in dhcp['shared_network_name'].items(): if 'shared_network_parameters' in network_config: DeprecationWarning(f'Additional shared network parameters in "{network}" {common_deprecation_msg}') if 'disable' in network_config: disabled_shared_networks += 1 if 'subnet' not in network_config: raise ConfigError(f'No subnets defined for {network}. At least one\n' \ 'lease subnet must be configured.') for subnet, subnet_config in network_config['subnet'].items(): if 'subnet_parameters' in subnet_config: DeprecationWarning(f'Additional subnet parameters in "{subnet}" {common_deprecation_msg}') # All delivered static routes require a next-hop to be set if 'static_route' in subnet_config: for route, route_option in subnet_config['static_route'].items(): if 'next_hop' not in route_option: raise ConfigError(f'DHCP static-route "{route}" requires router to be defined!') # DHCP failover needs at least one subnet that uses it if 'enable_failover' in subnet_config: if 'failover' not in dhcp: raise ConfigError(f'Can not enable failover for "{subnet}" in "{network}".\n' \ 'Failover is not configured globally!') failover_ok = True # Check if DHCP address range is inside configured subnet declaration if 'range' in subnet_config: networks = [] for range, range_config in subnet_config['range'].items(): if not {'start', 'stop'} <= set(range_config): raise ConfigError(f'DHCP range "{range}" start and stop address must be defined!') # Start/Stop address must be inside network for key in ['start', 'stop']: if ip_address(range_config[key]) not in ip_network(subnet): raise ConfigError(f'DHCP range "{range}" {key} address not within shared-network "{network}, {subnet}"!') # Stop address must be greater or equal to start address if ip_address(range_config['stop']) < ip_address(range_config['start']): raise ConfigError(f'DHCP range "{range}" stop address must be greater or equal\n' \ 'to the ranges start address!') for network in networks: start = range_config['start'] stop = range_config['stop'] if start in network: raise ConfigError(f'Range "{range}" start address "{start}" already part of another range!') if stop in network: raise ConfigError(f'Range "{range}" stop address "{stop}" already part of another range!') tmp = IPRange(range_config['start'], range_config['stop']) networks.append(tmp) # Exclude addresses must be in bound if 'exclude' in subnet_config: for exclude in subnet_config['exclude']: if ip_address(exclude) not in ip_network(subnet): raise ConfigError(f'Excluded IP address "{exclude}" not within shared-network "{network}, {subnet}"!') # At least one DHCP address range or static-mapping required if 'range' not in subnet_config and 'static_mapping' not in subnet_config: raise ConfigError(f'No DHCP address range or active static-mapping configured\n' \ f'within shared-network "{network}, {subnet}"!') if 'static_mapping' in subnet_config: # Static mappings require just a MAC address (will use an IP from the dynamic pool if IP is not set) used_ips = [] used_mac = [] for mapping, mapping_config in subnet_config['static_mapping'].items(): if 'ip_address' in mapping_config: if ip_address(mapping_config['ip_address']) not in ip_network(subnet): raise ConfigError(f'Configured static lease address for mapping "{mapping}" is\n' \ f'not within shared-network "{network}, {subnet}"!') if 'mac_address' not in mapping_config: raise ConfigError(f'MAC address required for static mapping "{mapping}"\n' \ f'within shared-network "{network}, {subnet}"!') if 'disable' not in mapping_config: if mapping_config['ip_address'] in used_ips: raise ConfigError(f'Configured IP address for static mapping "{mapping}" already exists on another static mapping') used_ips.append(mapping_config['ip_address']) if 'mac_address' in mapping_config and 'disable' not in mapping_config: if mapping_config['mac_address'] in used_mac: raise ConfigError(f'Configured MAC address for static mapping "{mapping}" already exists on another static mapping') used_mac.append(mapping_config['mac_address']) # There must be one subnet connected to a listen interface. # This only counts if the network itself is not disabled! if 'disable' not in network_config: if is_subnet_connected(subnet, primary=False): listen_ok = True # Subnets must be non overlapping if subnet in subnets: raise ConfigError(f'Configured subnets must be unique! Subnet "{subnet}"\n' 'defined multiple times!') subnets.append(subnet) # Check for overlapping subnets net = ip_network(subnet) for n in subnets: net2 = ip_network(n) if (net != net2): if net.overlaps(net2): raise ConfigError(f'Conflicting subnet ranges: "{net}" overlaps "{net2}"!') # Prevent 'disable' for shared-network if only one network is configured if (shared_networks - disabled_shared_networks) < 1: raise ConfigError(f'At least one shared network must be active!') if 'failover' in dhcp: if not failover_ok: raise ConfigError('DHCP failover must be enabled for at least one subnet!') for key in ['name', 'remote', 'source_address', 'status']: if key not in dhcp['failover']: tmp = key.replace('_', '-') raise ConfigError(f'DHCP failover requires "{tmp}" to be specified!') for address in (dict_search('listen_address', dhcp) or []): - if is_addr_assigned(address): + if is_addr_assigned(address, include_vrf=True): listen_ok = True # no need to probe further networks, we have one that is valid continue else: raise ConfigError(f'listen-address "{address}" not configured on any interface') - if not listen_ok: raise ConfigError('None of the configured subnets have an appropriate primary IP address on any\n' 'broadcast interface configured, nor was there an explicit listen-address\n' 'configured for serving DHCP relay packets!') return None def generate(dhcp): # bail out early - looks like removal from running config if not dhcp or 'disable' in dhcp: return None # Please see: https://vyos.dev/T1129 for quoting of the raw # parameters we can pass to ISC DHCPd tmp_file = '/tmp/dhcpd.conf' render(tmp_file, 'dhcp-server/dhcpd.conf.j2', dhcp, formater=lambda _: _.replace(""", '"')) # XXX: as we have the ability for a user to pass in "raw" options via VyOS # CLI (see T3544) we now ask ISC dhcpd to test the newly rendered # configuration tmp = run(f'/usr/sbin/dhcpd -4 -q -t -cf {tmp_file}') if tmp > 0: if os.path.exists(tmp_file): os.unlink(tmp_file) raise ConfigError('Configuration file errors encountered - check your options!') # Now that we know that the newly rendered configuration is "good" we can # render the "real" configuration render(config_file, 'dhcp-server/dhcpd.conf.j2', dhcp, formater=lambda _: _.replace(""", '"')) render(systemd_override, 'dhcp-server/10-override.conf.j2', dhcp) # Clean up configuration test file if os.path.exists(tmp_file): os.unlink(tmp_file) return None def apply(dhcp): call('systemctl daemon-reload') # bail out early - looks like removal from running config if not dhcp or 'disable' in dhcp: call('systemctl stop isc-dhcp-server.service') if os.path.exists(config_file): os.unlink(config_file) return None call('systemctl restart isc-dhcp-server.service') return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)