diff options
Diffstat (limited to 'sleekxmpp/xmlstream/resolver.py')
| -rw-r--r-- | sleekxmpp/xmlstream/resolver.py | 109 |
1 files changed, 83 insertions, 26 deletions
diff --git a/sleekxmpp/xmlstream/resolver.py b/sleekxmpp/xmlstream/resolver.py index e82bfdb7..188e5ac7 100644 --- a/sleekxmpp/xmlstream/resolver.py +++ b/sleekxmpp/xmlstream/resolver.py @@ -32,10 +32,10 @@ log = logging.getLogger(__name__) #: cd dnspython #: git checkout python3 #: python3 setup.py install -USE_DNSPYTHON = False +DNSPYTHON_AVAILABLE = False try: import dns.resolver - USE_DNSPYTHON = True + DNSPYTHON_AVAILABLE = True except ImportError as e: log.debug("Could not find dnspython package. " + \ "Not all features will be available") @@ -47,13 +47,13 @@ def default_resolver(): :returns: A :class:`dns.resolver.Resolver` object if dnspython is available. Otherwise, ``None``. """ - if USE_DNSPYTHON: + if DNSPYTHON_AVAILABLE: return dns.resolver.get_default_resolver() return None def resolve(host, port=None, service=None, proto='tcp', - resolver=None, use_ipv6=True): + resolver=None, use_ipv6=True, use_dnspython=True): """Peform DNS resolution for a given hostname. Resolution may perform SRV record lookups if a service and protocol @@ -77,6 +77,9 @@ def resolve(host, port=None, service=None, proto='tcp', :param use_ipv6: Optionally control the use of IPv6 in situations where it is either not available, or performance is degraded. Defaults to ``True``. + :param use_dnspython: Optionally control if dnspython is used to make + the DNS queries instead of the built-in DNS + library. :type host: string :type port: int @@ -84,14 +87,22 @@ def resolve(host, port=None, service=None, proto='tcp', :type proto: string :type resolver: :class:`dns.resolver.Resolver` :type use_ipv6: bool + :type use_dnspython: bool :return: An iterable of IP address, port pairs in the order dictated by SRV priorities and weights, if applicable. """ + + if not use_dnspython: + if DNSPYTHON_AVAILABLE: + log.debug("DNS: Not using dnspython, but dnspython is installed.") + else: + log.debug("DNS: Not using dnspython.") + if not use_ipv6: log.debug("DNS: Use of IPv6 has been disabled.") - if resolver is None and USE_DNSPYTHON: + if resolver is None and DNSPYTHON_AVAILABLE and use_dnspython: resolver = dns.resolver.get_default_resolver() # An IPv6 literal is allowed to be enclosed in square brackets, but @@ -122,7 +133,9 @@ def resolve(host, port=None, service=None, proto='tcp', if not service: hosts = [(host, port)] else: - hosts = get_SRV(host, port, service, proto, resolver=resolver) + hosts = get_SRV(host, port, service, proto, + resolver=resolver, + use_dnspython=use_dnspython) for host, port in hosts: results = [] @@ -131,16 +144,18 @@ def resolve(host, port=None, service=None, proto='tcp', results.append((host, '::1', port)) results.append((host, '127.0.0.1', port)) if use_ipv6: - for address in get_AAAA(host): + for address in get_AAAA(host, resolver=resolver, + use_dnspython=use_dnspython): results.append((host, address, port)) - for address in get_A(host): + for address in get_A(host, resolver=resolver, + use_dnspython=use_dnspython): results.append((host, address, port)) for host, address, port in results: yield host, address, port -def get_A(host): +def get_A(host, resolver=None, use_dnspython=True): """Lookup DNS A records for a given host. If ``resolver`` is not provided, or is ``None``, then resolution will @@ -148,9 +163,13 @@ def get_A(host): :param host: The hostname to resolve for A record IPv4 addresses. :param resolver: Optional DNS resolver object to use for the query. + :param use_dnspython: Optionally control if dnspython is used to make + the DNS queries instead of the built-in DNS + library. :type host: string :type resolver: :class:`dns.resolver.Resolver` or ``None`` + :type use_dnspython: bool :return: A list of IPv4 literals. """ @@ -158,15 +177,32 @@ def get_A(host): # If not using dnspython, attempt lookup using the OS level # getaddrinfo() method. + if resolver is None or not use_dnspython: + try: + recs = socket.getaddrinfo(host, None, socket.AF_INET, + socket.SOCK_STREAM) + return [rec[4][0] for rec in recs] + except socket.gaierror: + log.debug("DNS: Error retreiving A address info for %s." % host) + return [] + + # Using dnspython: try: - recs = socket.getaddrinfo(host, None, socket.AF_INET, - socket.SOCK_STREAM) - return [rec[4][0] for rec in recs] - except socket.gaierror: - log.debug("DNS: Error retreiving A address info for %s." % host) + recs = resolver.query(host, dns.rdatatype.A) + return [rec.to_text() for rec in recs] + except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer): + log.debug("DNS: No A records for %s" % host) + return [] + except dns.exception.Timeout: + log.debug("DNS: A record resolution timed out for %s" % host) + return [] + except dns.exception.DNSException as e: + log.debug("DNS: Error querying A records for %s" % host) + log.exception(e) return [] -def get_AAAA(host): + +def get_AAAA(host, resolver=None, use_dnspython=True): """Lookup DNS AAAA records for a given host. If ``resolver`` is not provided, or is ``None``, then resolution will @@ -174,9 +210,13 @@ def get_AAAA(host): :param host: The hostname to resolve for AAAA record IPv6 addresses. :param resolver: Optional DNS resolver object to use for the query. + :param use_dnspython: Optionally control if dnspython is used to make + the DNS queries instead of the built-in DNS + library. :type host: string :type resolver: :class:`dns.resolver.Resolver` or ``None`` + :type use_dnspython: bool :return: A list of IPv6 literals. """ @@ -184,19 +224,36 @@ def get_AAAA(host): # If not using dnspython, attempt lookup using the OS level # getaddrinfo() method. - if not socket.has_ipv6: - log.debug("Unable to query %s for AAAA records: IPv6 is not supported", host) - return [] + if resolver is None or not use_dnspython: + if not socket.has_ipv6: + log.debug("Unable to query %s for AAAA records: IPv6 is not supported", host) + return [] + try: + recs = socket.getaddrinfo(host, None, socket.AF_INET6, + socket.SOCK_STREAM) + return [rec[4][0] for rec in recs] + except (OSError, socket.gaierror): + log.debug("DNS: Error retreiving AAAA address " + \ + "info for %s." % host) + return [] + + # Using dnspython: try: - recs = socket.getaddrinfo(host, None, socket.AF_INET6, - socket.SOCK_STREAM) - return [rec[4][0] for rec in recs] - except (OSError, socket.gaierror): - log.debug("DNS: Error retreiving AAAA address " + \ - "info for %s." % host) + recs = resolver.query(host, dns.rdatatype.AAAA) + return [rec.to_text() for rec in recs] + except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer): + log.debug("DNS: No AAAA records for %s" % host) + return [] + except dns.exception.Timeout: + log.debug("DNS: AAAA record resolution timed out for %s" % host) return [] + except dns.exception.DNSException as e: + log.debug("DNS: Error querying AAAA records for %s" % host) + log.exception(e) + return [] + -def get_SRV(host, port, service, proto='tcp', resolver=None): +def get_SRV(host, port, service, proto='tcp', resolver=None, use_dnspython=True): """Perform SRV record resolution for a given host. .. note:: @@ -222,7 +279,7 @@ def get_SRV(host, port, service, proto='tcp', resolver=None): :return: A list of hostname, port pairs in the order dictacted by SRV priorities and weights. """ - if resolver is None: + if resolver is None or not use_dnspython: log.warning("DNS: dnspython not found. Can not use SRV lookup.") return [(host, port)] |