summaryrefslogtreecommitdiff
path: root/src/op_mode/dhcp.py
diff options
context:
space:
mode:
Diffstat (limited to 'src/op_mode/dhcp.py')
-rwxr-xr-xsrc/op_mode/dhcp.py278
1 files changed, 278 insertions, 0 deletions
diff --git a/src/op_mode/dhcp.py b/src/op_mode/dhcp.py
new file mode 100755
index 000000000..07e9b7d6c
--- /dev/null
+++ b/src/op_mode/dhcp.py
@@ -0,0 +1,278 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2022 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 sys
+from ipaddress import ip_address
+import typing
+
+from datetime import datetime
+from sys import exit
+from tabulate import tabulate
+from isc_dhcp_leases import IscDhcpLeases
+
+from vyos.base import Warning
+from vyos.configquery import ConfigTreeQuery
+
+from vyos.util import cmd
+from vyos.util import dict_search
+from vyos.util import is_systemd_service_running
+
+import vyos.opmode
+
+
+config = ConfigTreeQuery()
+pool_key = "shared-networkname"
+
+
+def _in_pool(lease, pool):
+ if pool_key in lease.sets:
+ if lease.sets[pool_key] == pool:
+ return True
+ return False
+
+
+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, pool=None) -> 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 not None:
+ if config.exists(f'service dhcp-server shared-network-name {pool}'):
+ leases = list(filter(lambda x: _in_pool(x, pool), leases))
+ 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 family == 'inet':
+ data_lease['hardware'] = 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'] = 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]
+ else:
+ data_lease['remaining'] = ''
+
+ # Do not add old leases
+ if data_lease['remaining'] != '':
+ 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)
+
+ return data
+
+
+def _get_formatted_server_leases(raw_data, family):
+ data_entries = []
+ if family == 'inet':
+ for lease in raw_data:
+ ipaddr = lease.get('ip')
+ hw_addr = lease.get('hardware')
+ 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')
+ 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', 'Hardware 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: str, 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: str):
+ # if dhcp server is down, inactive leases may still be shown as active, so warn the user.
+ if not is_systemd_service_running('isc-dhcp-server.service'):
+ Warning('DHCP server is configured but not started. Data may be stale.')
+
+ leases = _get_raw_server_leases(family)
+ if raw:
+ return leases
+ else:
+ return _get_formatted_server_leases(leases, 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)