diff options
Diffstat (limited to 'src/conf_mode/dhcp_server.py')
| -rwxr-xr-x | src/conf_mode/dhcp_server.py | 328 |
1 files changed, 0 insertions, 328 deletions
diff --git a/src/conf_mode/dhcp_server.py b/src/conf_mode/dhcp_server.py deleted file mode 100755 index ac7d95632..000000000 --- a/src/conf_mode/dhcp_server.py +++ /dev/null @@ -1,328 +0,0 @@ -#!/usr/bin/env python3 -# -# Copyright (C) 2018-2023 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 <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.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 - - - # A shared-network requires a subnet definition - for network, network_config in dhcp['shared_network_name'].items(): - 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(): - # 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) - 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}"!') - - # 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): - 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) |