Python dns.resolver.Timeout() Examples

def process(self, headers, content):
        request = Services.get("request_factory")
        hostname = urlparse(request.url).hostname
        _ = False
        try:
            resolver = Resolver(configure=False)
            resolver.nameservers = [settings.dns_resolver]
            resolver.timeout = 2
            resolver.lifetime = 2

            dns_query = resolver.query(hostname, "CNAME")

            if len(dns_query) > 0:
                for answer in dns_query:
                    _ |= re.search(r"cloudfront\.net", str(answer), re.I) is not None
            if _:
                return "CloudFront CDN (Amazon)"
        except NoAnswer:
            pass
        except NXDOMAIN:
            pass
        except Timeout:
            pass 

def process(self, headers, content):
        request = Services.get("request_factory")
        hostname = urlparse(request.url).hostname
        try:
            resolver = Resolver(configure=False)
            resolver.nameservers = [settings.dns_resolver]
            resolver.timeout = 2
            resolver.lifetime = 2

            dns_query = resolver.query(hostname + ".edgekey.net", "A")

            if len(dns_query) > 0:
                return "Akamai CDN"

        except NXDOMAIN:
            pass
        except NoAnswer:
            pass
        except Timeout:
            pass 

def process(self, headers, content):
        request = Services.get("request_factory")
        hostname = urlparse(request.url).hostname
        _ = False

        try:
            resolver = Resolver(configure=False)
            resolver.nameservers = [settings.dns_resolver]
            resolver.timeout = 2
            resolver.lifetime = 2

            dns_query = resolver.query(hostname, "CNAME")
            if len(dns_query) > 0:
                for answer in dns_query:
                    _ |= re.search(r"azureedge\.net", str(answer), re.I) is not None
            if _:
                return "Azure CDN"
        except NoAnswer:
            pass
        except NXDOMAIN:
            pass
        except Timeout:
            pass 

def process(self, headers, content):
        request = Services.get("request_factory")
        hostname = urlparse(request.url).hostname
        try:
            resolver = Resolver(configure=False)
            resolver.nameservers = [settings.dns_resolver]
            resolver.timeout = 2
            resolver.lifetime = 2
            dns_query = resolver.query(hostname + ".cdn.cloudflare.net", "A")

            if len(dns_query) > 0:
                return "Cloudflare CDN"

        except NXDOMAIN:
            pass
        except NoAnswer:
            pass
        except Timeout:
            pass 

def process(self, headers, content):
        request = Services.get("request_factory")
        hostname = urlparse(request.url).hostname
        _ = False
        try:
            resolver = Resolver(configure=False)
            resolver.nameservers = [settings.dns_resolver]
            resolver.timeout = 2
            resolver.lifetime = 2

            dns_query = resolver.query(hostname, "CNAME")
            if len(dns_query) > 0:
                for answer in dns_query:
                    _ |= re.search(r"fastly\.net", str(answer), re.I) is not None
            if _:
                return "Fastly CDN"
        except NoAnswer:
            pass
        except NXDOMAIN:
            pass
        except Timeout:
            pass 

def resolve_ns(data, t='A', timeout=HUNTER_RESOLVER_TIMEOUT):
    resolver = dns.resolver.Resolver()
    resolver.timeout = timeout
    resolver.lifetime = timeout
    resolver.search = []
    try:
        answers = resolver.query(data, t)
        resp = []
        for rdata in answers:
            resp.append(rdata)
    except (NoAnswer, NXDOMAIN, EmptyLabel, NoNameservers, Timeout) as e:
        if str(e).startswith('The DNS operation timed out after'):
            logger.info('{} - {} -- this may be normal'.format(data, e))
            return []

        if not str(e).startswith('The DNS response does not contain an answer to the question'):
            if not str(e).startswith('None of DNS query names exist'):
                logger.info('{} - {}'.format(data, e))
        return []

    return resp 

def get_mx_domains(domain, dns_resolver=_dns_resolver):
    """ Retrieve and return the MX records for a domain. """
    mx_records = []
    try:
        mx_records = dns_resolver().query(domain, 'MX')
    except NoNameservers:
        log.error('NoMXservers', domain=domain)
    except NXDOMAIN:
        log.error('No such domain', domain=domain)
    except Timeout:
        log.error('Time out during resolution', domain=domain)
        raise
    except NoAnswer:
        log.error('No answer from provider', domain=domain)
        mx_records = _fallback_get_mx_domains(domain)

    return [str(rdata.exchange).lower() for rdata in mx_records] 

def lookup_host(self, hostname, keep_going=True):
        result = set()

        for source in self.bind_addresses or [None]:
            if source is None:
                self.resolver.nameservers = self.nameservers
            else:
                self.resolver.nameservers = [str(dns) for dns in self.dns_servers if dns.version == source.version]
                if not self.resolver.nameservers:
                    continue

            for rectype in self.rectypes:
                try:
                    # print("Issuing query for hostname %r, rectype %r, source %r, search_domains %r, nameservers %r" % (
                    #     hostname, rectype, source, self.resolver.search_domains, self.resolver.nameservers), file=stderr)
                    a = self.resolver.query(hostname, rectype, source=str(source))
                    print("Got results: %r" % list(a), file=stderr)
                except (NXDOMAIN, NoAnswer):
                    pass
                except Timeout:
                    # No point in retrying with a different rectype if these DNS server(s) are not responding
                    break
                else:
                    result.update(ip_address(r.address) for r in a)
                if result and not keep_going:
                    return result

        return result or None 

def process(self, i, router):
        if i.itype != 'fqdn':
            return

        if 'search' in i.tags:
            return

        try:
            r = resolve_ns(i.indicator, t='CNAME')
        except Timeout:
            self.logger.info('timeout trying to resolve: {}'.format(i.indicator))
            r = []

        for rr in r:
            # http://serverfault.com/questions/44618/is-a-wildcard-cname-dns-record-valid
            rr = str(rr).rstrip('.').lstrip('*.')
            if rr in ['', 'localhost', '0.0.0.0']:
                continue

            fqdn = Indicator(**i.__dict__())
            fqdn.indicator = rr
            fqdn.lasttime = arrow.utcnow()

            try:
                resolve_itype(fqdn.indicator)
            except InvalidIndicator as e:
                self.logger.error(fqdn)
                self.logger.error(e)
                return

            fqdn.itype = 'fqdn'
            fqdn.confidence = (fqdn.confidence - 1)
            router.indicators_create(fqdn) 

def process(self, i, router):
        if i.itype != 'fqdn':
            return

        if 'search' in i.tags:
            return

        try:
            r = resolve_ns(i.indicator)
        except Timeout:
            self.logger.info('timeout trying to resolve: {}'.format(i.indicator))
            return

        for rr in r:
            if str(rr).rstrip('.') in ["", 'localhost', '0.0.0.0']:
                continue

            ip = Indicator(**i.__dict__())
            ip.indicator = str(rr)
            ip.lasttime = arrow.utcnow()

            try:
                resolve_itype(ip.indicator)
            except InvalidIndicator as e:
                self.logger.error(ip)
                self.logger.error(e)
            else:
                ip.itype = 'ipv4'
                ip.rdata = i.indicator
                ip.confidence = (ip.confidence - 4) if ip.confidence >= 4 else 0
                router.indicators_create(ip) 

def process(self, i, router):
        if i.itype != 'fqdn':
            return

        if 'search' in i.tags:
            return

        try:
            r = resolve_ns(i.indicator, t='MX')
        except Timeout:
            self.logger.info('timeout trying to resolve MX for: {}'.format(i.indicator))
            return

        for rr in r:
            rr = re.sub(r'^\d+ ', '', str(rr))
            rr = str(rr).rstrip('.')

            if rr in ["", 'localhost', '0.0.0.0']:
                continue

            fqdn = Indicator(**i.__dict__())
            fqdn.indicator = rr.rstrip('.')
            fqdn.lasttime = arrow.utcnow()

            # 10
            if re.match('^\d+$', rr):
                return

            try:
                resolve_itype(fqdn.indicator)
            except InvalidIndicator as e:
                self.logger.info(fqdn)
                self.logger.info(e)
            else:
                fqdn.itype = 'fqdn'
                fqdn.rdata = i.indicator
                fqdn.confidence = (fqdn.confidence - 5) if fqdn.confidence >= 5 else 0
                router.indicators_create(fqdn) 

def process(self, i, router):
        if i.itype != 'fqdn':
            return

        if 'search' in i.tags:
            return

        try:
            r = resolve_ns(i.indicator)
        except Timeout:
            self.logger.info('timeout trying to resolve: {}'.format(i.indicator))
            return

        for rr in r:
            rr = str(rr)
            if rr in ["", 'localhost', '0.0.0.0']:
                continue

            ip = Indicator(**i.__dict__())
            ip.lasttime = arrow.utcnow()

            ip.indicator = rr
            try:
                resolve_itype(ip.indicator)
            except InvalidIndicator as e:
                self.logger.error(ip)
                self.logger.error(e)
            else:
                ip.itype = 'ipv4'
                ip.rdata = i.indicator
                ip.confidence = (ip.confidence - 2) if ip.confidence >= 2 else 0
                router.indicators_create(ip)

                # also create a passive dns tag
                ip.tags = 'pdns'
                ip.confidence = 10
                router.indicators_create(ip) 

def consumer(self):
        while True:
            try:
                hostname, rtype = self.queue.get(True, 5)
            except Empty:
                logging.debug("Empty! Bailing")
                return
            try:
                logging.debug("Starting work on {}".format(hostname))
                results = self.resolver.query(hostname, rtype)
                if results:
                    if hostname not in self.results:
                        self.results[hostname] = {}
                    text_results = []
                    for r in results:
                        if isinstance(r, NS_class):
                            text_results.append(r.target.to_text())
                        elif isinstance(r, A_class):
                            text_results.append(r.to_text())
                        else:
                            logging.error(
                                "Unknown record type: {}".format(type(r)))
                    hostname = Hostname(value=hostname)
                    ResolveHostnames.each(hostname, rtype, text_results)
            except NoAnswer:
                continue
            except NXDOMAIN:
                continue
            except Timeout:
                logging.debug("Request timed out for {}".format(hostname))
                continue
            except NoNameservers:
                continue
            except Exception as e:
                import traceback
                logging.error(
                    "Unknown error occurred while working on {} ({})".format(
                        hostname, rtype))
                logging.error("\nERROR: {}".format(hostname, rtype, e))
                logging.error(traceback.print_exc())

            continue 

def gc_connect(self, protocol='ldap'):
        """
        Connect to the global catalog
        """
        if self.hostname in self.ad.gcs():
            # This server is a Global Catalog
            initial_server = self.hostname
        else:
            # Pick the first GC server
            try:
                initial_server = self.ad.gcs()[0]
            except IndexError:
                # TODO: implement fallback options for GC detection?
                logging.error('Could not find a Global Catalog in this domain!'\
                              ' Resolving will be unreliable in forests with multiple domains')
                return False
        try:
            # Convert the hostname to an IP, this prevents ldap3 from doing it
            # which doesn't use our custom nameservers
            logging.info('Connecting to GC LDAP server: %s' % initial_server)
            q = self.ad.dnsresolver.query(initial_server, tcp=self.ad.dns_tcp)
            for r in q:
                ip = r.address
        except (resolver.NXDOMAIN, resolver.Timeout):
            for server in self.ad.gcs():
                # Skip the one we already tried
                if server == initial_server:
                    continue
                try:
                    # Convert the hostname to an IP, this prevents ldap3 from doing it
                    # which doesn't use our custom nameservers
                    logging.info('Connecting to GC LDAP server: %s' % server)
                    q = self.ad.dnsresolver.query(server, tcp=self.ad.dns_tcp)
                    for r in q:
                        ip = r.address
                        break
                except (resolver.NXDOMAIN, resolver.Timeout):
                    continue

        self.gcldap = self.ad.auth.getLDAPConnection(hostname=ip, gc=True,
                                                     baseDN=self.ad.baseDN, protocol=protocol)
        return self.gcldap is not None 

def provider_from_address(email_address, dns_resolver=_dns_resolver):
    if not EMAIL_REGEX.match(email_address):
        raise InvalidEmailAddressError('Invalid email address')

    domain = email_address.split('@')[1].lower()
    mx_domains = get_mx_domains(domain, dns_resolver)
    ns_records = []
    try:
        ns_records = dns_resolver().query(domain, 'NS')
    except NoNameservers:
        log.error('NoNameservers', domain=domain)
    except NXDOMAIN:
        log.error('No such domain', domain=domain)
    except Timeout:
        log.error('Time out during resolution', domain=domain)
    except NoAnswer:
        log.error('No answer from provider', domain=domain)

    for (name, info) in providers.iteritems():
        provider_domains = info.get('domains', [])

        # If domain is in the list of known domains for a provider,
        # return the provider.
        for d in provider_domains:
            if domain.endswith(d):
                return name

    for (name, info) in providers.iteritems():
        provider_mx = info.get('mx_servers', [])

        # If a retrieved mx_domain is in the list of stored MX domains for a
        # provider, return the provider.
        if mx_match(mx_domains, provider_mx):
            return name

    for (name, info) in providers.iteritems():
        provider_ns = info.get('ns_servers', [])

        # If a retrieved name server is in the list of stored name servers for
        # a provider, return the provider.
        for rdata in ns_records:
            if str(rdata).lower() in provider_ns:
                return name

    return 'unknown'


# From tornado.httputil