# Copyright (C) 2006, 2007, 2009, 2011 Nominum, Inc. # # Permission to use, copy, modify, and distribute this software and its # documentation for any purpose with or without fee is hereby granted, # provided that the above copyright notice and this permission notice # appear in all copies. # # THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT # OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. """DNS E.164 helpers @var public_enum_domain: The DNS public ENUM domain, e164.arpa. @type public_enum_domain: dns.name.Name object """ import dns.exception import dns.name import dns.resolver from ._compat import string_types public_enum_domain = dns.name.from_text('e164.arpa.') def from_e164(text, origin=public_enum_domain): """Convert an E.164 number in textual form into a Name object whose value is the ENUM domain name for that number. @param text: an E.164 number in textual form. @type text: str @param origin: The domain in which the number should be constructed. The default is e164.arpa. @type origin: dns.name.Name object or None @rtype: dns.name.Name object """ parts = [d for d in text if d.isdigit()] parts.reverse() return dns.name.from_text('.'.join(parts), origin=origin) def to_e164(name, origin=public_enum_domain, want_plus_prefix=True): """Convert an ENUM domain name into an E.164 number. @param name: the ENUM domain name. @type name: dns.name.Name object. @param origin: A domain containing the ENUM domain name. The name is relativized to this domain before being converted to text. @type origin: dns.name.Name object or None @param want_plus_prefix: if True, add a '+' to the beginning of the returned number. @rtype: str """ if origin is not None: name = name.relativize(origin) dlabels = [d for d in name.labels if d.isdigit() and len(d) == 1] if len(dlabels) != len(name.labels): raise dns.exception.SyntaxError('non-digit labels in ENUM domain name') dlabels.reverse() text = b''.join(dlabels) if want_plus_prefix: text = b'+' + text return text def query(number, domains, resolver=None): """Look for NAPTR RRs for the specified number in the specified domains. e.g. lookup('16505551212', ['e164.dnspython.org.', 'e164.arpa.']) """ if resolver is None: resolver = dns.resolver.get_default_resolver() e_nx = dns.resolver.NXDOMAIN() for domain in domains: if isinstance(domain, string_types): domain = dns.name.from_text(domain) qname = dns.e164.from_e164(number, domain) try: return resolver.query(qname, 'NAPTR') except dns.resolver.NXDOMAIN as e: e_nx += e raise e_nx