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| # Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license | |
| # Copyright (C) 2006-2017 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.""" | |
| from typing import Iterable, Optional, Union | |
| import dns.exception | |
| import dns.name | |
| import dns.resolver | |
| #: The public E.164 domain. | |
| public_enum_domain = dns.name.from_text("e164.arpa.") | |
| def from_e164( | |
| text: str, origin: Optional[dns.name.Name] = public_enum_domain | |
| ) -> dns.name.Name: | |
| """Convert an E.164 number in textual form into a Name object whose | |
| value is the ENUM domain name for that number. | |
| Non-digits in the text are ignored, i.e. "16505551212", | |
| "+1.650.555.1212" and "1 (650) 555-1212" are all the same. | |
| *text*, a ``str``, is an E.164 number in textual form. | |
| *origin*, a ``dns.name.Name``, the domain in which the number | |
| should be constructed. The default is ``e164.arpa.``. | |
| Returns a ``dns.name.Name``. | |
| """ | |
| parts = [d for d in text if d.isdigit()] | |
| parts.reverse() | |
| return dns.name.from_text(".".join(parts), origin=origin) | |
| def to_e164( | |
| name: dns.name.Name, | |
| origin: Optional[dns.name.Name] = public_enum_domain, | |
| want_plus_prefix: bool = True, | |
| ) -> str: | |
| """Convert an ENUM domain name into an E.164 number. | |
| Note that dnspython does not have any information about preferred | |
| number formats within national numbering plans, so all numbers are | |
| emitted as a simple string of digits, prefixed by a '+' (unless | |
| *want_plus_prefix* is ``False``). | |
| *name* is a ``dns.name.Name``, the ENUM domain name. | |
| *origin* is a ``dns.name.Name``, a domain containing the ENUM | |
| domain name. The name is relativized to this domain before being | |
| converted to text. If ``None``, no relativization is done. | |
| *want_plus_prefix* is a ``bool``. If True, add a '+' to the beginning of | |
| the returned number. | |
| Returns a ``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.decode() | |
| def query( | |
| number: str, | |
| domains: Iterable[Union[dns.name.Name, str]], | |
| resolver: Optional[dns.resolver.Resolver] = None, | |
| ) -> dns.resolver.Answer: | |
| """Look for NAPTR RRs for the specified number in the specified domains. | |
| e.g. lookup('16505551212', ['e164.dnspython.org.', 'e164.arpa.']) | |
| *number*, a ``str`` is the number to look for. | |
| *domains* is an iterable containing ``dns.name.Name`` values. | |
| *resolver*, a ``dns.resolver.Resolver``, is the resolver to use. If | |
| ``None``, the default resolver is used. | |
| """ | |
| if resolver is None: | |
| resolver = dns.resolver.get_default_resolver() | |
| e_nx = dns.resolver.NXDOMAIN() | |
| for domain in domains: | |
| if isinstance(domain, str): | |
| domain = dns.name.from_text(domain) | |
| qname = dns.e164.from_e164(number, domain) | |
| try: | |
| return resolver.resolve(qname, "NAPTR") | |
| except dns.resolver.NXDOMAIN as e: | |
| e_nx += e | |
| raise e_nx | |