Source code for univention.admin.handlers.dns.reverse_zone

# -*- coding: utf-8 -*-
#
# Copyright 2004-2022 Univention GmbH
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"""
|UDM| module for |DNS| reverse zones
"""

import ldap.dn

from univention.admin.layout import Tab, Group
from univention.admin import configRegistry

import univention.admin.filter
import univention.admin.handlers
import univention.admin.localization
from univention.admin.handlers.dns import ARPA_IP4, ARPA_IP6, escapeSOAemail, unescapeSOAemail

translation = univention.admin.localization.translation('univention.admin.handlers.dns')
_ = translation.translate

module = 'dns/reverse_zone'
operations = ['add', 'edit', 'remove', 'search']
columns = ['nameserver']
childs = True
childmodules = ['dns/ptr_record']
short_description = _('DNS: Reverse lookup zone')
object_name = _('Reverse lookup zone')
object_name_plural = _('Reverse lookup zones')
long_description = _('Map IP addresses back to hostnames.')
options = {
	'default': univention.admin.option(
		short_description=short_description,
		default=True,
		objectClasses=['top', 'dNSZone'],
	),
}
property_descriptions = {
	'subnet': univention.admin.property(
		short_description=_('Subnet'),
		long_description=_('The networks address in forward notation.'),
		syntax=univention.admin.syntax.reverseLookupSubnet,
		include_in_default_search=True,
		required=True,
		may_change=False,
		identifies=True
	),
	'zonettl': univention.admin.property(
		short_description=_('Zone time to live'),
		long_description=_('The time this entry may be cached.'),
		syntax=univention.admin.syntax.UNIX_TimeInterval,
		required=True,
		default=(('3', 'hours'), []),
		dontsearch=True,
	),
	'contact': univention.admin.property(
		short_description=_('Contact person'),
		long_description=_('The email address of the person responsible for this zone.'),
		syntax=univention.admin.syntax.string,
		required=True,
		default=('root@%s.' % configRegistry.get('domainname', ''), []),
	),
	'serial': univention.admin.property(
		short_description=_('Serial number'),
		long_description=_('The sequence number for this zone. Updates automatically.'),
		syntax=univention.admin.syntax.integer,
		required=True,
		default=('1', [])
	),
	'refresh': univention.admin.property(
		short_description=_('Refresh interval'),
		long_description=_('The time interval secondary DNS servers use to check the zone for updates.'),
		syntax=univention.admin.syntax.UNIX_TimeInterval,
		required=True,
		default=(('8', 'hours'), [])
	),
	'retry': univention.admin.property(
		short_description=_('Retry interval'),
		long_description=_('The time interval secondary DNS servers use to retry failed refresh updates.'),
		syntax=univention.admin.syntax.UNIX_TimeInterval,
		required=True,
		default=(('2', 'hours'), [])
	),
	'expire': univention.admin.property(
		short_description=_('Expiry interval'),
		long_description=_('The time interval after which secondary DNS servers will expire failed zones.'),
		syntax=univention.admin.syntax.UNIX_TimeInterval,
		required=True,
		default=(('7', 'days'), [])
	),
	'ttl': univention.admin.property(
		short_description=_('Negative time to live'),
		long_description=_('The time interval "not found" answers are cached.'),
		syntax=univention.admin.syntax.UNIX_TimeInterval,
		required=True,
		default=(('1', 'days'), [])
	),
	'nameserver': univention.admin.property(
		short_description=_('Name server'),
		long_description=_('The FQDNs of the servers serving this zone.'),
		syntax=univention.admin.syntax.dnsHostname,
		multivalue=True,
		required=True,
	),
}

layout = [
	Tab(_('General'), _('Basic settings'), layout=[
		Group(_('General reverse lookup zone settings'), layout=[
			'subnet',
			'zonettl',
			'nameserver'
		]),
	]),
	Tab(_('Start of authority'), _('Primary name server information'), layout=[
		Group(_('Start of authority'), layout=[
			'contact',
			'serial',
			['refresh', 'retry'],
			['expire', 'ttl']
		]),
	])
]


[docs]def mapSubnet(subnet, encoding=()): """ Map subnet to reverse zone. >>> mapSubnet('0123:4567:89ab:cdef') 'f.e.d.c.b.a.9.8.7.6.5.4.3.2.1.0.ip6.arpa' >>> mapSubnet('0123:4567:89ab:cd') 'd.c.b.a.9.8.7.6.5.4.3.2.1.0.ip6.arpa' >>> mapSubnet('1.2.3') '3.2.1.in-addr.arpa' """ if u':' in subnet: # IPv6 subnet = u'%s%s' % (u'.'.join(subnet.replace(u':', u'')[::-1]), ARPA_IP6) else: subnet = u'%s%s' % (u'.'.join(subnet.split(u'.')[::-1]), ARPA_IP4) return subnet.encode(*encoding)
[docs]def unmapSubnet(zone, encoding=()): """ Map reverse zone to subnet. >>> unmapSubnet([b'f.e.d.c.b.a.9.8.7.6.5.4.3.2.1.0.ip6.arpa']) '0123:4567:89ab:cdef' >>> unmapSubnet([b'd.c.b.a.9.8.7.6.5.4.3.2.1.0.ip6.arpa']) '0123:4567:89ab:cd' >>> unmapSubnet([b'3.2.1.in-addr.arpa']) '1.2.3' """ if isinstance(zone, list): zone = zone[0] zone = zone.decode(*encoding) if zone.endswith(ARPA_IP6): # IPv6 zone = zone[:-len(ARPA_IP6)] zone = zone.split(u'.')[::-1] return u':'.join([u''.join(zone[i:i + 4]) for i in range(0, len(zone), 4)]) elif zone.endswith(ARPA_IP4): # IPv4 zone = zone[:-len(ARPA_IP4)] q = zone.split(u'.') q.reverse() return u'.'.join(q) else: raise ValueError('Neither an IPv4 nor an IPv6 reverse address')
mapping = univention.admin.mapping.mapping() mapping.register('subnet', 'zoneName', mapSubnet, unmapSubnet, encoding='ASCII') mapping.register('zonettl', 'dNSTTL', univention.admin.mapping.mapUNIX_TimeInterval, univention.admin.mapping.unmapUNIX_TimeInterval) mapping.register('nameserver', 'nSRecord', encoding='ASCII')
[docs]class object(univention.admin.handlers.simpleLdap): module = module def __init__(self, co, lo, position, dn='', superordinate=None, attributes=[]): univention.admin.handlers.simpleLdap.__init__(self, co, lo, position, dn, superordinate, attributes=attributes) if not self.dn and not self.position: raise univention.admin.uexceptions.insufficientInformation(_('Neither DN nor position given.'))
[docs] def open(self): univention.admin.handlers.simpleLdap.open(self) soa = self.oldattr.get('sOARecord', [b''])[0].split(b' ') if len(soa) > 6: self['contact'] = unescapeSOAemail(soa[1].decode('UTF-8')) self['serial'] = soa[2].decode('UTF-8') self['refresh'] = univention.admin.mapping.unmapUNIX_TimeInterval(soa[3]) self['retry'] = univention.admin.mapping.unmapUNIX_TimeInterval(soa[4]) self['expire'] = univention.admin.mapping.unmapUNIX_TimeInterval(soa[5]) self['ttl'] = univention.admin.mapping.unmapUNIX_TimeInterval(soa[6]) self.save()
def _ldap_modlist(self): ml = univention.admin.handlers.simpleLdap._ldap_modlist(self) if self.hasChanged(['nameserver', 'contact', 'serial', 'refresh', 'retry', 'expire', 'ttl']): if self['contact'] and not self['contact'].endswith('.'): self['contact'] += '.' for i in range(0, len(self['nameserver'])): if len(self['nameserver'][i]) > 0 \ and ':' not in self['nameserver'][i] \ and '.' in self['nameserver'][i] \ and not self['nameserver'][i].endswith('.'): self['nameserver'][i] += '.' refresh = univention.admin.mapping.mapUNIX_TimeInterval(self['refresh']) retry = univention.admin.mapping.mapUNIX_TimeInterval(self['retry']) expire = univention.admin.mapping.mapUNIX_TimeInterval(self['expire']) ttl = univention.admin.mapping.mapUNIX_TimeInterval(self['ttl']) soa = b'%s %s %s %s %s %s %s' % (self['nameserver'][0].encode('UTF-8'), escapeSOAemail(self['contact']).encode('UTF-8'), self['serial'].encode('UTF-8'), refresh, retry, expire, ttl) ml.append(('sOARecord', self.oldattr.get('sOARecord', []), soa)) return ml def _ldap_pre_modify(self): super(object, self)._ldap_pre_modify() # update SOA record if not self.hasChanged('serial'): self['serial'] = str(int(self['serial']) + 1) def _ldap_addlist(self): return super(object, self)._ldap_addlist() + [ ('relativeDomainName', [b'@']) ] # FIXME: there should be general solution; subnet is just a naming # attribute (though calculated from rdn)
[docs] def description(self): if 0: # open? return self['subnet'] else: rdn_value = ldap.dn.str2dn(self.dn)[0][0][1].encode('UTF-8') return unmapSubnet([rdn_value])
[docs] @classmethod def unmapped_lookup_filter(cls): return univention.admin.filter.conjunction('&', [ univention.admin.filter.expression('objectClass', 'dNSZone'), univention.admin.filter.expression('relativeDomainName', '@'), univention.admin.filter.conjunction('|', [ univention.admin.filter.expression('zoneName', '*%s' % ARPA_IP4, escape=False), univention.admin.filter.expression('zoneName', '*%s' % ARPA_IP6, escape=False) ]), ])
lookup = object.lookup lookup_filter = object.lookup_filter
[docs]def identify(dn, attr): return b'dNSZone' in attr.get('objectClass', []) and \ [b'@'] == attr.get('relativeDomainName', []) and \ (attr['zoneName'][0].decode('ASCII').endswith(ARPA_IP4) or attr['zoneName'][0].decode('ASCII').endswith(ARPA_IP6))