# Authors: # Pavel Zuna # # Copyright (C) 2010 Red Hat # see file 'COPYING' for use and warranty information # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # 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 . """ Domain Name System (DNS) Manage DNS zone and resource records. EXAMPLES: Add new zone: ipa dnszone-add example.com --name-server nameserver.example.com --admin-email admin@example.com Add second nameserver for example.com: ipa dnsrecord-add example.com @ --ns-rec nameserver2.example.com Add a mail server for example.com: ipa dnsrecord-add example.com @ --mx-rec="10 mail2" Delete previously added nameserver from example.com: ipa dnsrecord-del example.com @ --ns-rec nameserver2.example.com Add new A record for www.example.com: (random IP) ipa dnsrecord-add example.com www --a-rec 80.142.15.2 Add new PTR record for www.example.com ipa dnsrecord-add 15.142.80.in-addr.arpa 2 --ptr-rec www.example.com. Add new SRV records for LDAP servers. Three quarters of the requests should go to fast.example.com, one quarter to slow.example.com. If neither is available, switch to backup.example.com. ipa dnsrecord-add example.com _ldap._tcp --srv-rec="0 3 389 fast.example.com" ipa dnsrecord-add example.com _ldap._tcp --srv-rec="0 1 389 slow.example.com" ipa dnsrecord-add example.com _ldap._tcp --srv-rec="1 1 389 backup.example.com" Show zone example.com: ipa dnszone-show example.com Find zone with "example" in its domain name: ipa dnszone-find example Find records for resources with "www" in their name in zone example.com: ipa dnsrecord-find example.com www Find A records with value 10.10.0.1 in zone example.com ipa dnsrecord-find example.com --a-rec 10.10.0.1 Show records for resource www in zone example.com ipa dnsrecord-show example.com www Delete zone example.com with all resource records: ipa dnszone-del example.com Resolve a host name to see if it exists (will add default IPA domain if one is not included): ipa dns-resolve www.example.com ipa dns-resolve www """ import netaddr import time from ipalib import api, errors, output from ipalib import Command from ipalib import Flag, Int, List, Str, StrEnum from ipalib.plugins.baseldap import * from ipalib import _, ngettext from ipapython import dnsclient # supported resource record types _record_types = ( u'A', u'AAAA', u'A6', u'AFSDB', u'APL', u'CERT', u'CNAME', u'DHCID', u'DLV', u'DNAME', u'DNSKEY', u'DS', u'HIP', u'IPSECKEY', u'KEY', u'KX', u'LOC', u'MX', u'NAPTR', u'NS', u'NSEC', u'NSEC3', u'NSEC3PARAM', u'PTR', u'RRSIG', u'RP', u'SIG', u'SPF', u'SRV', u'SSHFP', u'TA', u'TKEY', u'TSIG', u'TXT', ) # attributes derived from record types _record_attributes = [str('%srecord' % t.lower()) for t in _record_types] # supported DNS classes, IN = internet, rest is almost never used _record_classes = (u'IN', u'CS', u'CH', u'HS') # normalizer for admin email def _rname_normalizer(value): value = value.replace('@', '.') if not value.endswith('.'): value += '.' return value def _create_zone_serial(**kwargs): """Generate serial number for zones.""" return int('%s01' % time.strftime('%Y%d%m')) def _validate_ipaddr(ugettext, ipaddr): try: ip = netaddr.IPAddress(ipaddr) except (netaddr.AddrFormatError, ValueError): return u'invalid address format' return None def _validate_ipnet(ugettext, ipnet): try: net = netaddr.IPNetwork(ipnet) except (UnboundLocalError, ValueError): return u'invalid format' return None def _validate_srv(ugettext, srv): try: prio, weight, port, host = srv.split() except ValueError: return u'format must be specified as "priority weight port target"' try: prio = int(prio) weight = int(weight) port = int(port) except ValueError: return u'the values of priority, weight and port must be integers' return None def _validate_mx(ugettext, mx): try: prio, host = mx.split() except ValueError: return u'format must be specified as "priority mailserver"' try: prio = int(prio) except ValueError: return u'the value of priority must be integer' if prio < 0 or prio > 65535: return u'the value of priority must be between 0 and 65535' return None def _validate_naptr(ugettext, naptr): "see RFC 2915 " try: order, pref, flags, svc, regexp, replacement = naptr.split() except ValueError: return u'format must be specified as "order preference flags service regexp replacement"' try: order = int(order) pref = int(pref) except ValueError: return u'order and preference must be integers' if order < 0 or order > 65535 or pref < 0 or pref > 65535: return u'the value of order and preference must be between 0 and 65535' flags = flags.replace('"','') flags = flags.replace('\'','') if len(flags) != 1: return u'flag must be a single character (quotation is allowed)' if flags.upper() not in "SAUP": return u'flag must be one of "S", "A", "U", or "P"' return None _record_validators = { u'A': _validate_ipaddr, u'AAAA': _validate_ipaddr, u'APL': _validate_ipnet, u'SRV': _validate_srv, u'MX': _validate_mx, u'NAPTR': _validate_naptr, } # dictionary of valid reverse zone -> number of address components _valid_reverse_zones = { '.in-addr.arpa.' : 4, '.ip6.arpa.' : 32, } def has_cli_options(entry, no_option_msg): entry = dict((t, entry.get(t, [])) for t in _record_attributes) numattr = reduce(lambda x,y: x+y, map(lambda x: len(x), [ v for v in entry.values() if v is not None ])) if numattr == 0: raise errors.OptionError(no_option_msg) return entry def is_ns_rec_resolvable(name): try: return api.Command['dns_resolve'](name) except errors.NotFound: raise errors.NotFound( reason=_('Nameserver \'%(host)s\' does not have a corresponding A/AAAA record') % {'host': name} ) def add_forward_record(zone, name, str_address): addr = netaddr.IPAddress(str_address) try: if addr.version == 4: api.Command['dnsrecord_add'](zone, name, arecord=str_address) elif addr.version == 6: api.Command['dnsrecord_add'](zone, name, aaaarecord=str_address) else: raise ValueError('Invalid address family') except errors.EmptyModlist: pass # the entry already exists and matches def dns_container_exists(ldap): try: ldap.get_entry(api.env.container_dns, []) except errors.NotFound: return False return True class dnszone(LDAPObject): """ DNS Zone, container for resource records. """ container_dn = api.env.container_dns object_name = 'DNS zone' object_name_plural = 'DNS zones' object_class = ['top', 'idnsrecord', 'idnszone'] default_attributes = [ 'idnsname', 'idnszoneactive', 'idnssoamname', 'idnssoarname', 'idnssoaserial', 'idnssoarefresh', 'idnssoaretry', 'idnssoaexpire', 'idnssoaminimum' ] + _record_attributes label = _('DNS') takes_params = ( Str('idnsname', cli_name='name', label=_('Zone name'), doc=_('Zone name (FQDN)'), normalizer=lambda value: value.lower(), primary_key=True, ), Str('idnssoamname', cli_name='name_server', label=_('Authoritative nameserver'), doc=_('Authoritative nameserver.'), ), Str('idnssoarname', cli_name='admin_email', label=_('Administrator e-mail address'), doc=_('Administrator e-mail address'), default_from=lambda idnsname: 'root.%s' % idnsname, normalizer=_rname_normalizer, ), Int('idnssoaserial?', cli_name='serial', label=_('SOA serial'), doc=_('SOA record serial number'), minvalue=1, create_default=_create_zone_serial, autofill=True, ), Int('idnssoarefresh?', cli_name='refresh', label=_('SOA refresh'), doc=_('SOA record refresh time'), minvalue=0, default=3600, autofill=True, ), Int('idnssoaretry?', cli_name='retry', label=_('SOA retry'), doc=_('SOA record retry time'), minvalue=0, default=900, autofill=True, ), Int('idnssoaexpire?', cli_name='expire', label=_('SOA expire'), doc=_('SOA record expire time'), default=1209600, minvalue=0, autofill=True, ), Int('idnssoaminimum?', cli_name='minimum', label=_('SOA minimum'), doc=_('How long should negative responses be cached'), default=3600, minvalue=0, maxvalue=10800, autofill=True, ), Int('dnsttl?', cli_name='ttl', label=_('SOA time to live'), doc=_('SOA record time to live'), ), StrEnum('dnsclass?', cli_name='class', label=_('SOA class'), doc=_('SOA record class'), values=_record_classes, ), Str('idnsupdatepolicy?', cli_name='update_policy', label=_('BIND update policy'), doc=_('BIND update policy'), ), Flag('idnszoneactive?', cli_name='zone_active', label=_('Active zone'), doc=_('Is zone active?'), flags=['no_create', 'no_update'], attribute=True, ), Flag('idnsallowdynupdate', cli_name='allow_dynupdate', label=_('Dynamic update'), doc=_('Allow dynamic updates.'), attribute=True, ), ) api.register(dnszone) class dnszone_add(LDAPCreate): """ Create new DNS zone (SOA record). """ takes_options = LDAPCreate.takes_options + ( Flag('force', doc=_('Force DNS zone creation even if nameserver not in DNS.'), ), Str('ip_address?', _validate_ipaddr, doc=_('Add the nameserver to DNS with this IP address'), ), ) def pre_callback(self, ldap, dn, entry_attrs, *keys, **options): if not dns_container_exists(self.api.Backend.ldap2): raise errors.NotFound(reason=_('DNS is not configured')) entry_attrs['idnszoneactive'] = 'TRUE' entry_attrs['idnsallowdynupdate'] = str( entry_attrs.get('idnsallowdynupdate', False) ).upper() # Check nameserver has a forward record nameserver = entry_attrs['idnssoamname'] if not 'ip_address' in options and not options['force']: is_ns_rec_resolvable(nameserver) if nameserver[-1] != '.': nameserver += '.' entry_attrs['nsrecord'] = nameserver entry_attrs['idnssoamname'] = nameserver return dn def post_callback(self, ldap, dn, entry_attrs, *keys, **options): if 'ip_address' in options: nameserver = entry_attrs['idnssoamname'][0][:-1] # ends with a dot nsparts = nameserver.split('.') add_forward_record('.'.join(nsparts[1:]), nsparts[0], options['ip_address']) return dn api.register(dnszone_add) class dnszone_del(LDAPDelete): """ Delete DNS zone (SOA record). """ api.register(dnszone_del) class dnszone_mod(LDAPUpdate): """ Modify DNS zone (SOA record). """ def pre_callback(self, ldap, dn, entry_attrs, *keys, **options): entry_attrs['idnsallowdynupdate'] = str( entry_attrs.get('idnsallowdynupdate', False) ).upper() return dn api.register(dnszone_mod) class dnszone_find(LDAPSearch): """ Search for DNS zones (SOA records). """ api.register(dnszone_find) class dnszone_show(LDAPRetrieve): """ Display information about a DNS zone (SOA record). """ api.register(dnszone_show) class dnszone_disable(LDAPQuery): """ Disable DNS Zone. """ has_output = output.standard_value msg_summary = _('Disabled DNS zone "%(value)s"') def execute(self, *keys, **options): ldap = self.obj.backend dn = self.obj.get_dn(*keys, **options) try: ldap.update_entry(dn, {'idnszoneactive': 'FALSE'}) except errors.EmptyModlist: pass return dict(result=True, value=keys[-1]) api.register(dnszone_disable) class dnszone_enable(LDAPQuery): """ Enable DNS Zone. """ has_output = output.standard_value msg_summary = _('Enabled DNS zone "%(value)s"') def execute(self, *keys, **options): ldap = self.obj.backend dn = self.obj.get_dn(*keys, **options) try: ldap.update_entry(dn, {'idnszoneactive': 'TRUE'}) except errors.EmptyModlist: pass return dict(result=True, value=keys[-1]) api.register(dnszone_enable) class dnsrecord(LDAPObject): """ DNS record. """ parent_object = 'dnszone' container_dn = api.env.container_dns object_name = 'DNS resource record' object_name_plural = 'DNS resource records' object_class = ['top', 'idnsrecord'] default_attributes = _record_attributes + ['idnsname'] label = _('DNS resource record') takes_params = ( Str('idnsname', cli_name='name', label=_('Record name'), doc=_('Record name'), primary_key=True, ), Int('dnsttl?', cli_name='ttl', label=_('Time to live'), doc=_('Time to live'), ), StrEnum('dnsclass?', cli_name='class', label=_('Class'), doc=_('DNS class'), values=_record_classes, ), ) def is_pkey_zone_record(self, *keys): idnsname = keys[-1] if idnsname == '@' or idnsname == ('%s.' % keys[-2]): return True return False def get_dn(self, *keys, **options): if self.is_pkey_zone_record(*keys): return self.api.Object[self.parent_object].get_dn(*keys[:-1], **options) return super(dnsrecord, self).get_dn(*keys, **options) def attr_to_cli(self, attr): try: cliname = attr[:-len('record')].upper() except IndexError: cliname = attr return cliname api.register(dnsrecord) class dnsrecord_cmd_w_record_options(Command): """ Base class for DNS record commands with record options. """ record_param_doc = 'comma-separated list of %s records' def get_record_options(self): for t in _record_types: t = t.encode('utf-8') doc = self.record_param_doc % t validator = _record_validators.get(t) if validator: yield List( '%srecord?' % t.lower(), validator, cli_name='%s_rec' % t.lower(), doc=doc, label='%s record' % t, attribute=True ) else: yield List( '%srecord?' % t.lower(), cli_name='%s_rec' % t.lower(), doc=doc, label='%s record' % t, attribute=True ) def record_options_2_entry(self, **options): entries = dict((t, options.get(t, [])) for t in _record_attributes) entries.update(dict((k, []) for (k,v) in entries.iteritems() if v == None )) return entries class dnsrecord_mod_record(LDAPQuery, dnsrecord_cmd_w_record_options): """ Base class for adding/removing records from DNS resource entries. """ has_output = output.standard_entry def get_options(self): for option in super(dnsrecord_mod_record, self).get_options(): yield option for option in self.get_record_options(): yield option def execute(self, *keys, **options): ldap = self.obj.backend dn = self.obj.get_dn(*keys, **options) entry_attrs = self.record_options_2_entry(**options) dn = self.pre_callback(ldap, dn, entry_attrs, *keys, **options) try: (dn, old_entry_attrs) = ldap.get_entry(dn, entry_attrs.keys()) except errors.NotFound: self.obj.handle_not_found(*keys) self.update_old_entry_callback(entry_attrs, old_entry_attrs) try: ldap.update_entry(dn, old_entry_attrs) except errors.EmptyModlist: pass if options.get('all', False): attrs_list = ['*'] else: attrs_list = list( set(self.obj.default_attributes + entry_attrs.keys()) ) try: (dn, entry_attrs) = ldap.get_entry(dn, attrs_list) except errors.NotFound: self.obj.handle_not_found(*keys) if self.obj.is_pkey_zone_record(*keys): entry_attrs[self.obj.primary_key.name] = [u'@'] retval = self.post_callback(keys, entry_attrs) if retval: return retval return dict(result=entry_attrs, value=keys[-1]) def update_old_entry_callback(self, entry_attrs, old_entry_attrs): pass def pre_callback(self, ldap, dn, entry_attrs, *keys, **options): return dn def post_callback(self, keys, entry_attrs): pass class dnsrecord_add_record(dnsrecord_mod_record): """ Add records to DNS resource. """ NO_CLI = True def update_old_entry_callback(self, entry_attrs, old_entry_attrs): for (a, v) in entry_attrs.iteritems(): if not isinstance(v, (list, tuple)): v = [v] old_entry_attrs.setdefault(a, []) old_entry_attrs[a] += v api.register(dnsrecord_add_record) class dnsrecord_add(LDAPCreate, dnsrecord_cmd_w_record_options): """ Add new DNS resource record. """ no_option_msg = 'No options to add a specific record provided.' takes_options = LDAPCreate.takes_options + ( Flag('force', flags=['no_option', 'no_output'], doc=_('force NS record creation even if its hostname is not in DNS'), ), ) def get_options(self): for option in super(dnsrecord_add, self).get_options(): yield option for option in self.get_record_options(): yield option def args_options_2_entry(self, *keys, **options): has_cli_options(options, self.no_option_msg) return super(dnsrecord_add, self).args_options_2_entry(*keys, **options) def _nsrecord_pre_callback(self, ldap, dn, entry_attrs, *keys, **options): if options.get('force', False): return dn for ns in options['nsrecord']: is_ns_rec_resolvable(ns) return dn def _ptrrecord_pre_callback(self, ldap, dn, entry_attrs, *keys, **options): components = dn.split(',',2) addr = components[0].split('=')[1] zone = components[1].split('=')[1] zone_len = 0 for valid_zone in _valid_reverse_zones: if zone.find(valid_zone) != -1: zone = zone.replace(valid_zone,'') zone_name = valid_zone zone_len = _valid_reverse_zones[valid_zone] if not zone_len: allowed_zones = ', '.join(_valid_reverse_zones) raise errors.ValidationError(name='cn', error=unicode(_('Reverse zone for PTR record should be a sub-zone of one the following fully qualified domains: %s') % allowed_zones)) ip_addr_comp_count = len(addr.split('.')) + len(zone.split('.')) if ip_addr_comp_count != zone_len: raise errors.ValidationError(name='cn', error=unicode(_('Reverse zone %s requires exactly %d IP address components, %d given') % (zone_name, zone_len, ip_addr_comp_count))) for ptr in options['ptrrecord']: if not ptr.endswith('.'): raise errors.ValidationError(name='ptr-rec', error=unicode(_('PTR record \'%s\' is not fully qualified (check traling \'.\')') % ptr)) return dn def pre_callback(self, ldap, dn, entry_attrs, *keys, **options): for rtype in options: rtype_cb = '_%s_pre_callback' % rtype if hasattr(self, rtype_cb): dn = getattr(self, rtype_cb)(ldap, dn, entry_attrs, *keys, **options) return dn def exc_callback(self, keys, options, exc, call_func, *call_args, **call_kwargs): if call_func.func_name == 'add_entry': if isinstance(exc, errors.DuplicateEntry): self.obj.methods.add_record( *keys, **self.record_options_2_entry(**options) ) return raise exc api.register(dnsrecord_add) class dnsrecord_delentry(LDAPDelete): """ Delete DNS record entry. """ msg_summary = _('Deleted record "%(value)s"') NO_CLI = True api.register(dnsrecord_delentry) class dnsrecord_del(dnsrecord_mod_record): """ Delete DNS resource record. """ no_option_msg = _('Neither --del-all nor options to delete a specific record provided.') takes_options = ( Flag('del_all', default=False, label=_('Delete all associated records'), ), ) def execute(self, *keys, **options): if options.get('del_all', False): return self.obj.methods.delentry(*keys) return super(dnsrecord_del, self).execute(*keys, **options) def record_options_2_entry(self, **options): entry = super(dnsrecord_del, self).record_options_2_entry(**options) return has_cli_options(entry, self.no_option_msg) def update_old_entry_callback(self, entry_attrs, old_entry_attrs): for (a, v) in entry_attrs.iteritems(): if not isinstance(v, (list, tuple)): v = [v] for val in v: try: old_entry_attrs[a].remove(val) except (KeyError, ValueError): raise errors.NotFound(reason=_('%s record with value %s not found') % (self.obj.attr_to_cli(a), val)) def post_callback(self, keys, entry_attrs): if not self.obj.is_pkey_zone_record(*keys): for a in _record_attributes: if a in entry_attrs and entry_attrs[a]: return return self.obj.methods.delentry(*keys) api.register(dnsrecord_del) class dnsrecord_show(LDAPRetrieve, dnsrecord_cmd_w_record_options): """ Display DNS resource. """ def has_output_params(self): for option in self.get_record_options(): yield option def post_callback(self, ldap, dn, entry_attrs, *keys, **options): if self.obj.is_pkey_zone_record(*keys): entry_attrs[self.obj.primary_key.name] = [u'@'] return dn api.register(dnsrecord_show) class dnsrecord_find(LDAPSearch, dnsrecord_cmd_w_record_options): """ Search for DNS resources. """ def get_options(self): for option in super(dnsrecord_find, self).get_options(): yield option for option in self.get_record_options(): yield option.clone(query=True) def pre_callback(self, ldap, filter, attrs_list, base_dn, scope, *args, **options): record_attrs = self.record_options_2_entry(**options) record_filter = ldap.make_filter(record_attrs, rules=ldap.MATCH_ALL) filter = ldap.combine_filters( (filter, record_filter), rules=ldap.MATCH_ALL ) return (filter, base_dn, ldap.SCOPE_SUBTREE) def post_callback(self, ldap, entries, truncated, *args, **options): if entries: zone_obj = self.api.Object[self.obj.parent_object] zone_dn = zone_obj.get_dn(args[0]) if entries[0][0] == zone_dn: entries[0][1][zone_obj.primary_key.name] = [u'@'] api.register(dnsrecord_find) class dns_resolve(Command): """ Resolve a host name in DNS """ has_output = output.standard_value msg_summary = _('Found \'%(value)s\'') takes_args = ( Str('hostname', label=_('Hostname'), ), ) def execute(self, *args, **options): query=args[0] if query.find(api.env.domain) == -1 and query.find('.') == -1: query = '%s.%s.' % (query, api.env.domain) if query[-1] != '.': query = query + '.' reca = dnsclient.query(query, dnsclient.DNS_C_IN, dnsclient.DNS_T_A) rec6 = dnsclient.query(query, dnsclient.DNS_C_IN, dnsclient.DNS_T_AAAA) records = reca + rec6 found = False for rec in records: if rec.dns_type == dnsclient.DNS_T_A or \ rec.dns_type == dnsclient.DNS_T_AAAA: found = True break if not found: raise errors.NotFound( reason=_('Host \'%(host)s\' not found') % {'host': query} ) return dict(result=True, value=query) api.register(dns_resolve) class dns_is_enabled(Command): """ Checks if any of the servers has the DNS service enabled. """ NO_CLI = True has_output = output.standard_value base_dn = 'cn=masters,cn=ipa,cn=etc,%s' % api.env.basedn filter = '(&(objectClass=ipaConfigObject)(cn=DNS))' def execute(self, *args, **options): ldap = self.api.Backend.ldap2 dns_enabled = False try: ent = ldap.find_entries(filter=self.filter, base_dn=self.base_dn) if len(ent): dns_enabled = True except Exception, e: pass return dict(result=dns_enabled, value=u'') api.register(dns_is_enabled)