diff options
Diffstat (limited to 'designate/dnsutils.py')
| -rw-r--r-- | designate/dnsutils.py | 152 |
1 files changed, 118 insertions, 34 deletions
diff --git a/designate/dnsutils.py b/designate/dnsutils.py index 6833d542..a3b4d2f9 100644 --- a/designate/dnsutils.py +++ b/designate/dnsutils.py @@ -21,9 +21,10 @@ from threading import Lock import six import dns import dns.exception +import dns.query +import dns.rdatatype import dns.zone import eventlet -from dns import rdatatype from oslo_serialization import base64 from oslo_log import log as logging @@ -313,7 +314,7 @@ def dnspyrecords_to_recordsetlist(dnspython_records): def dnspythonrecord_to_recordset(rname, rdataset): - record_type = rdatatype.to_text(rdataset.rdtype) + record_type = dns.rdatatype.to_text(rdataset.rdtype) name = rname.to_text() if six.PY3 and isinstance(name, bytes): @@ -347,39 +348,122 @@ def do_axfr(zone_name, servers, timeout=None, source=None): timeout = timeout or CONF["service:mdns"].xfr_timeout xfr = None - for srv in servers: - to = eventlet.Timeout(timeout) - log_info = {'name': zone_name, 'host': srv} - try: - LOG.info("Doing AXFR for %(name)s from %(host)s", log_info) - - xfr = dns.query.xfr(srv['host'], zone_name, relativize=False, - timeout=1, port=srv['port'], source=source) - raw_zone = dns.zone.from_xfr(xfr, relativize=False) - break - except eventlet.Timeout as t: - if t == to: - LOG.error("AXFR timed out for %(name)s from %(host)s", - log_info) - continue - except dns.exception.FormError: - LOG.error("Zone %(name)s is not present on %(host)s." - "Trying next server.", log_info) - except socket.error: - LOG.error("Connection error when doing AXFR for %(name)s from " - "%(host)s", log_info) - except Exception: - LOG.exception("Problem doing AXFR %(name)s from %(host)s. " + for address in get_ip_addresses(srv['host']): + to = eventlet.Timeout(timeout) + log_info = {'name': zone_name, 'host': srv, 'address': address} + try: + LOG.info( + 'Doing AXFR for %(name)s from %(host)s %(address)s', + log_info + ) + xfr = dns.query.xfr( + address, zone_name, relativize=False, timeout=1, + port=srv['port'], source=source + ) + raw_zone = dns.zone.from_xfr(xfr, relativize=False) + LOG.debug("AXFR Successful for %s", raw_zone.origin.to_text()) + return raw_zone + except eventlet.Timeout as t: + if t == to: + LOG.error("AXFR timed out for %(name)s from %(host)s", + log_info) + continue + except dns.exception.FormError: + LOG.error("Zone %(name)s is not present on %(host)s." "Trying next server.", log_info) - finally: - to.cancel() - continue - else: - raise exceptions.XFRFailure( - "XFR failed for %(name)s. No servers in %(servers)s was reached." % - {"name": zone_name, "servers": servers}) + except socket.error: + LOG.error("Connection error when doing AXFR for %(name)s from " + "%(host)s", log_info) + except Exception: + LOG.exception("Problem doing AXFR %(name)s from %(host)s. " + "Trying next server.", log_info) + finally: + to.cancel() + + raise exceptions.XFRFailure( + "XFR failed for %(name)s. No servers in %(servers)s was reached." % + {"name": zone_name, "servers": servers} + ) + + +def prepare_msg(zone_name, rdatatype=dns.rdatatype.SOA, + dns_opcode=dns.opcode.QUERY): + """ + Do the needful to set up a dns packet with dnspython + """ + dns_message = dns.message.make_query(zone_name, rdatatype) + dns_message.set_opcode(dns_opcode) + + return dns_message + + +def dig(zone_name, host, rdatatype, port=53): + """ + Set up and send a regular dns query, datatype configurable + """ + query = prepare_msg(zone_name, rdatatype=rdatatype) + + return send_dns_message(query, host, port=port) + + +def notify(zone_name, host, port=53): + """ + Set up a notify packet and send it + """ + msg = prepare_msg(zone_name, dns_opcode=dns.opcode.NOTIFY) + + return send_dns_message(msg, host, port=port) - LOG.debug("AXFR Successful for %s", raw_zone.origin.to_text()) - return raw_zone +def send_dns_message(dns_message, host, port=53, timeout=10): + """ + Send the dns message and return the response + + :return: dns.Message of the response to the dns query + """ + ip_address = get_ip_address(host) + # This can raise some exceptions, but we'll catch them elsewhere + if not CONF['service:mdns'].all_tcp: + return dns.query.udp( + dns_message, ip_address, port=port, timeout=timeout) + return dns.query.tcp( + dns_message, ip_address, port=port, timeout=timeout) + + +def get_serial(zone_name, host, port=53): + """ + Possibly raises dns.exception.Timeout or dns.query.BadResponse. + Possibly returns 0 if, e.g., the answer section is empty. + """ + resp = dig(zone_name, host, dns.rdatatype.SOA, port=port) + if not resp.answer: + return 0 + rdataset = resp.answer[0].to_rdataset() + if not rdataset: + return 0 + return rdataset[0].serial + + +def get_ip_address(ip_address_or_hostname): + """ + Provide an ip or hostname and return a valid ip4 or ipv6 address. + + :return: ip address + """ + addresses = get_ip_addresses(ip_address_or_hostname) + if not addresses: + return None + return addresses[0] + + +def get_ip_addresses(ip_address_or_hostname): + """ + Provide an ip or hostname and return all valid ip4 or ipv6 addresses. + + :return: ip addresses + """ + addresses = [] + for res in socket.getaddrinfo(ip_address_or_hostname, 0): + addresses.append(res[4][0]) + return list(set(addresses)) |