#!/usr/bin/env python3 # # Copyright (C) 2022-2023 VyOS maintainers and contributors # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License version 2 or later as # published by the Free Software Foundation. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . import os import sys import typing from datetime import datetime from glob import glob from ipaddress import ip_address from isc_dhcp_leases import IscDhcpLeases from tabulate import tabulate import vyos.opmode from vyos.base import Warning from vyos.configquery import ConfigTreeQuery from vyos.utils.dict import dict_search from vyos.utils.file import read_file from vyos.utils.process import cmd from vyos.utils.process import is_systemd_service_running time_string = "%a %b %d %H:%M:%S %Z %Y" config = ConfigTreeQuery() lease_valid_states = ['all', 'active', 'free', 'expired', 'released', 'abandoned', 'reset', 'backup'] sort_valid_inet = ['end', 'mac', 'hostname', 'ip', 'pool', 'remaining', 'start', 'state'] sort_valid_inet6 = ['end', 'iaid_duid', 'ip', 'last_communication', 'pool', 'remaining', 'state', 'type'] ArgFamily = typing.Literal['inet', 'inet6'] ArgState = typing.Literal['all', 'active', 'free', 'expired', 'released', 'abandoned', 'reset', 'backup'] def _utc_to_local(utc_dt): return datetime.fromtimestamp((datetime.fromtimestamp(utc_dt) - datetime(1970, 1, 1)).total_seconds()) def _format_hex_string(in_str): out_str = "" # if input is divisible by 2, add : every 2 chars if len(in_str) > 0 and len(in_str) % 2 == 0: out_str = ':'.join(a+b for a,b in zip(in_str[::2], in_str[1::2])) else: out_str = in_str return out_str def _find_list_of_dict_index(lst, key='ip', value='') -> int: """ Find the index entry of list of dict matching the dict value Exampe: % lst = [{'ip': '192.0.2.1'}, {'ip': '192.0.2.2'}] % _find_list_of_dict_index(lst, key='ip', value='192.0.2.2') % 1 """ idx = next((index for (index, d) in enumerate(lst) if d[key] == value), None) return idx def _get_raw_server_leases(family='inet', pool=None, sorted=None, state=[]) -> list: """ Get DHCP server leases :return list """ lease_file = '/config/dhcpdv6.leases' if family == 'inet6' else '/config/dhcpd.leases' data = [] leases = IscDhcpLeases(lease_file).get() if pool is None: pool = _get_dhcp_pools(family=family) else: pool = [pool] for lease in leases: data_lease = {} data_lease['ip'] = lease.ip data_lease['state'] = lease.binding_state data_lease['pool'] = lease.sets.get('shared-networkname', '') data_lease['end'] = lease.end.timestamp() if lease.end else None if family == 'inet': data_lease['mac'] = lease.ethernet data_lease['start'] = lease.start.timestamp() data_lease['hostname'] = lease.hostname if family == 'inet6': data_lease['last_communication'] = lease.last_communication.timestamp() data_lease['iaid_duid'] = _format_hex_string(lease.host_identifier_string) lease_types_long = {'na': 'non-temporary', 'ta': 'temporary', 'pd': 'prefix delegation'} data_lease['type'] = lease_types_long[lease.type] data_lease['remaining'] = '-' if lease.end: data_lease['remaining'] = lease.end - datetime.utcnow() if data_lease['remaining'].days >= 0: # substraction gives us a timedelta object which can't be formatted with strftime # so we use str(), split gets rid of the microseconds data_lease['remaining'] = str(data_lease["remaining"]).split('.')[0] # Do not add old leases if data_lease['remaining'] != '' and data_lease['pool'] in pool and data_lease['state'] != 'free': if not state or data_lease['state'] in state: data.append(data_lease) # deduplicate checked = [] for entry in data: addr = entry.get('ip') if addr not in checked: checked.append(addr) else: idx = _find_list_of_dict_index(data, key='ip', value=addr) data.pop(idx) if sorted: if sorted == 'ip': data.sort(key = lambda x:ip_address(x['ip'])) else: data.sort(key = lambda x:x[sorted]) return data def _get_formatted_server_leases(raw_data, family='inet'): data_entries = [] if family == 'inet': for lease in raw_data: ipaddr = lease.get('ip') hw_addr = lease.get('mac') state = lease.get('state') start = lease.get('start') start = _utc_to_local(start).strftime('%Y/%m/%d %H:%M:%S') end = lease.get('end') end = _utc_to_local(end).strftime('%Y/%m/%d %H:%M:%S') if end else '-' remain = lease.get('remaining') pool = lease.get('pool') hostname = lease.get('hostname') data_entries.append([ipaddr, hw_addr, state, start, end, remain, pool, hostname]) headers = ['IP Address', 'MAC address', 'State', 'Lease start', 'Lease expiration', 'Remaining', 'Pool', 'Hostname'] if family == 'inet6': for lease in raw_data: ipaddr = lease.get('ip') state = lease.get('state') start = lease.get('last_communication') start = _utc_to_local(start).strftime('%Y/%m/%d %H:%M:%S') end = lease.get('end') end = _utc_to_local(end).strftime('%Y/%m/%d %H:%M:%S') remain = lease.get('remaining') lease_type = lease.get('type') pool = lease.get('pool') host_identifier = lease.get('iaid_duid') data_entries.append([ipaddr, state, start, end, remain, lease_type, pool, host_identifier]) headers = ['IPv6 address', 'State', 'Last communication', 'Lease expiration', 'Remaining', 'Type', 'Pool', 'IAID_DUID'] output = tabulate(data_entries, headers, numalign='left') return output def _get_dhcp_pools(family='inet') -> list: v = 'v6' if family == 'inet6' else '' pools = config.list_nodes(f'service dhcp{v}-server shared-network-name') return pools def _get_pool_size(pool, family='inet'): v = 'v6' if family == 'inet6' else '' base = f'service dhcp{v}-server shared-network-name {pool}' size = 0 subnets = config.list_nodes(f'{base} subnet') for subnet in subnets: if family == 'inet6': ranges = config.list_nodes(f'{base} subnet {subnet} address-range start') else: ranges = config.list_nodes(f'{base} subnet {subnet} range') for range in ranges: if family == 'inet6': start = config.list_nodes(f'{base} subnet {subnet} address-range start')[0] stop = config.value(f'{base} subnet {subnet} address-range start {start} stop') else: start = config.value(f'{base} subnet {subnet} range {range} start') stop = config.value(f'{base} subnet {subnet} range {range} stop') # Add +1 because both range boundaries are inclusive size += int(ip_address(stop)) - int(ip_address(start)) + 1 return size def _get_raw_pool_statistics(family='inet', pool=None): if pool is None: pool = _get_dhcp_pools(family=family) else: pool = [pool] v = 'v6' if family == 'inet6' else '' stats = [] for p in pool: subnet = config.list_nodes(f'service dhcp{v}-server shared-network-name {p} subnet') size = _get_pool_size(family=family, pool=p) leases = len(_get_raw_server_leases(family=family, pool=p)) use_percentage = round(leases / size * 100) if size != 0 else 0 pool_stats = {'pool': p, 'size': size, 'leases': leases, 'available': (size - leases), 'use_percentage': use_percentage, 'subnet': subnet} stats.append(pool_stats) return stats def _get_formatted_pool_statistics(pool_data, family='inet'): data_entries = [] for entry in pool_data: pool = entry.get('pool') size = entry.get('size') leases = entry.get('leases') available = entry.get('available') use_percentage = entry.get('use_percentage') use_percentage = f'{use_percentage}%' data_entries.append([pool, size, leases, available, use_percentage]) headers = ['Pool', 'Size','Leases', 'Available', 'Usage'] output = tabulate(data_entries, headers, numalign='left') return output def _verify(func): """Decorator checks if DHCP(v6) config exists""" from functools import wraps @wraps(func) def _wrapper(*args, **kwargs): config = ConfigTreeQuery() family = kwargs.get('family') v = 'v6' if family == 'inet6' else '' unconf_message = f'DHCP{v} server is not configured' # Check if config does not exist if not config.exists(f'service dhcp{v}-server'): raise vyos.opmode.UnconfiguredSubsystem(unconf_message) return func(*args, **kwargs) return _wrapper @_verify def show_pool_statistics(raw: bool, family: ArgFamily, pool: typing.Optional[str]): pool_data = _get_raw_pool_statistics(family=family, pool=pool) if raw: return pool_data else: return _get_formatted_pool_statistics(pool_data, family=family) @_verify def show_server_leases(raw: bool, family: ArgFamily, pool: typing.Optional[str], sorted: typing.Optional[str], state: typing.Optional[ArgState]): # if dhcp server is down, inactive leases may still be shown as active, so warn the user. v = '6' if family == 'inet6' else '' service_name = 'DHCPv6' if family == 'inet6' else 'DHCP' if not is_systemd_service_running(f'isc-dhcp-server{v}.service'): Warning(f'{service_name} server is configured but not started. Data may be stale.') v = 'v6' if family == 'inet6' else '' if pool and pool not in _get_dhcp_pools(family=family): raise vyos.opmode.IncorrectValue(f'DHCP{v} pool "{pool}" does not exist!') if state and state not in lease_valid_states: raise vyos.opmode.IncorrectValue(f'DHCP{v} state "{state}" is invalid!') sort_valid = sort_valid_inet6 if family == 'inet6' else sort_valid_inet if sorted and sorted not in sort_valid: raise vyos.opmode.IncorrectValue(f'DHCP{v} sort "{sorted}" is invalid!') lease_data = _get_raw_server_leases(family=family, pool=pool, sorted=sorted, state=state) if raw: return lease_data else: return _get_formatted_server_leases(lease_data, family=family) def _get_raw_client_leases(family='inet', interface=None): from time import mktime from datetime import datetime lease_dir = '/var/lib/dhcp' lease_files = [] lease_data = [] if interface: tmp = f'{lease_dir}/dhclient_{interface}.lease' if os.path.exists(tmp): lease_files.append(tmp) else: # All DHCP leases lease_files = glob(f'{lease_dir}/dhclient_*.lease') for lease in lease_files: tmp = {} with open(lease, 'r') as f: for line in f.readlines(): line = line.rstrip() if 'last_update' not in tmp: # ISC dhcp client contains least_update timestamp in human readable # format this makes less sense for an API and also the expiry # timestamp is provided in UNIX time. Convert string (e.g. Sun Jul # 30 18:13:44 CEST 2023) to UNIX time (1690733624) tmp.update({'last_update' : int(mktime(datetime.strptime(line, time_string).timetuple()))}) continue k, v = line.split('=') tmp.update({k : v.replace("'", "")}) lease_data.append(tmp) return lease_data def _get_formatted_client_leases(lease_data, family): from time import localtime from time import strftime from vyos.validate import is_intf_addr_assigned data_entries = [] for lease in lease_data: data_entries.append(["Interface", lease['interface']]) if 'new_ip_address' in lease: tmp = '[Active]' if is_intf_addr_assigned(lease['interface'], lease['new_ip_address']) else '[Inactive]' data_entries.append(["IP address", lease['new_ip_address'], tmp]) if 'new_subnet_mask' in lease: data_entries.append(["Subnet Mask", lease['new_subnet_mask']]) if 'new_domain_name' in lease: data_entries.append(["Domain Name", lease['new_domain_name']]) if 'new_routers' in lease: data_entries.append(["Router", lease['new_routers']]) if 'new_domain_name_servers' in lease: data_entries.append(["Name Server", lease['new_domain_name_servers']]) if 'new_dhcp_server_identifier' in lease: data_entries.append(["DHCP Server", lease['new_dhcp_server_identifier']]) if 'new_dhcp_lease_time' in lease: data_entries.append(["DHCP Server", lease['new_dhcp_lease_time']]) if 'last_update' in lease: tmp = strftime(time_string, localtime(int(lease['last_update']))) data_entries.append(["Last Update", tmp]) if 'new_expiry' in lease: tmp = strftime(time_string, localtime(int(lease['new_expiry']))) data_entries.append(["Expiry", tmp]) # Add empty marker data_entries.append(['']) output = tabulate(data_entries, tablefmt='plain') return output def show_client_leases(raw: bool, family: ArgFamily, interface: typing.Optional[str]): lease_data = _get_raw_client_leases(family=family, interface=interface) if raw: return lease_data else: return _get_formatted_client_leases(lease_data, family=family) if __name__ == '__main__': try: res = vyos.opmode.run(sys.modules[__name__]) if res: print(res) except (ValueError, vyos.opmode.Error) as e: print(e) sys.exit(1)