From 4a52a71956a8d46fcb7294ac71734504bb09bcc2 Mon Sep 17 00:00:00 2001 From: S. Solomon Darnell Date: Fri, 28 Mar 2025 21:52:21 -0500 Subject: two version of R2R are here --- .../python3.12/site-packages/dns/asyncresolver.py | 475 +++++++++++++++++++++ 1 file changed, 475 insertions(+) create mode 100644 .venv/lib/python3.12/site-packages/dns/asyncresolver.py (limited to '.venv/lib/python3.12/site-packages/dns/asyncresolver.py') diff --git a/.venv/lib/python3.12/site-packages/dns/asyncresolver.py b/.venv/lib/python3.12/site-packages/dns/asyncresolver.py new file mode 100644 index 00000000..8f5e062a --- /dev/null +++ b/.venv/lib/python3.12/site-packages/dns/asyncresolver.py @@ -0,0 +1,475 @@ +# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license + +# Copyright (C) 2003-2017 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. + +"""Asynchronous DNS stub resolver.""" + +import socket +import time +from typing import Any, Dict, List, Optional, Union + +import dns._ddr +import dns.asyncbackend +import dns.asyncquery +import dns.exception +import dns.name +import dns.query +import dns.rdataclass +import dns.rdatatype +import dns.resolver # lgtm[py/import-and-import-from] + +# import some resolver symbols for brevity +from dns.resolver import NXDOMAIN, NoAnswer, NoRootSOA, NotAbsolute + +# for indentation purposes below +_udp = dns.asyncquery.udp +_tcp = dns.asyncquery.tcp + + +class Resolver(dns.resolver.BaseResolver): + """Asynchronous DNS stub resolver.""" + + async def resolve( + self, + qname: Union[dns.name.Name, str], + rdtype: Union[dns.rdatatype.RdataType, str] = dns.rdatatype.A, + rdclass: Union[dns.rdataclass.RdataClass, str] = dns.rdataclass.IN, + tcp: bool = False, + source: Optional[str] = None, + raise_on_no_answer: bool = True, + source_port: int = 0, + lifetime: Optional[float] = None, + search: Optional[bool] = None, + backend: Optional[dns.asyncbackend.Backend] = None, + ) -> dns.resolver.Answer: + """Query nameservers asynchronously to find the answer to the question. + + *backend*, a ``dns.asyncbackend.Backend``, or ``None``. If ``None``, + the default, then dnspython will use the default backend. + + See :py:func:`dns.resolver.Resolver.resolve()` for the + documentation of the other parameters, exceptions, and return + type of this method. + """ + + resolution = dns.resolver._Resolution( + self, qname, rdtype, rdclass, tcp, raise_on_no_answer, search + ) + if not backend: + backend = dns.asyncbackend.get_default_backend() + start = time.time() + while True: + (request, answer) = resolution.next_request() + # Note we need to say "if answer is not None" and not just + # "if answer" because answer implements __len__, and python + # will call that. We want to return if we have an answer + # object, including in cases where its length is 0. + if answer is not None: + # cache hit! + return answer + assert request is not None # needed for type checking + done = False + while not done: + (nameserver, tcp, backoff) = resolution.next_nameserver() + if backoff: + await backend.sleep(backoff) + timeout = self._compute_timeout(start, lifetime, resolution.errors) + try: + response = await nameserver.async_query( + request, + timeout=timeout, + source=source, + source_port=source_port, + max_size=tcp, + backend=backend, + ) + except Exception as ex: + (_, done) = resolution.query_result(None, ex) + continue + (answer, done) = resolution.query_result(response, None) + # Note we need to say "if answer is not None" and not just + # "if answer" because answer implements __len__, and python + # will call that. We want to return if we have an answer + # object, including in cases where its length is 0. + if answer is not None: + return answer + + async def resolve_address( + self, ipaddr: str, *args: Any, **kwargs: Any + ) -> dns.resolver.Answer: + """Use an asynchronous resolver to run a reverse query for PTR + records. + + This utilizes the resolve() method to perform a PTR lookup on the + specified IP address. + + *ipaddr*, a ``str``, the IPv4 or IPv6 address you want to get + the PTR record for. + + All other arguments that can be passed to the resolve() function + except for rdtype and rdclass are also supported by this + function. + + """ + # We make a modified kwargs for type checking happiness, as otherwise + # we get a legit warning about possibly having rdtype and rdclass + # in the kwargs more than once. + modified_kwargs: Dict[str, Any] = {} + modified_kwargs.update(kwargs) + modified_kwargs["rdtype"] = dns.rdatatype.PTR + modified_kwargs["rdclass"] = dns.rdataclass.IN + return await self.resolve( + dns.reversename.from_address(ipaddr), *args, **modified_kwargs + ) + + async def resolve_name( + self, + name: Union[dns.name.Name, str], + family: int = socket.AF_UNSPEC, + **kwargs: Any, + ) -> dns.resolver.HostAnswers: + """Use an asynchronous resolver to query for address records. + + This utilizes the resolve() method to perform A and/or AAAA lookups on + the specified name. + + *qname*, a ``dns.name.Name`` or ``str``, the name to resolve. + + *family*, an ``int``, the address family. If socket.AF_UNSPEC + (the default), both A and AAAA records will be retrieved. + + All other arguments that can be passed to the resolve() function + except for rdtype and rdclass are also supported by this + function. + """ + # We make a modified kwargs for type checking happiness, as otherwise + # we get a legit warning about possibly having rdtype and rdclass + # in the kwargs more than once. + modified_kwargs: Dict[str, Any] = {} + modified_kwargs.update(kwargs) + modified_kwargs.pop("rdtype", None) + modified_kwargs["rdclass"] = dns.rdataclass.IN + + if family == socket.AF_INET: + v4 = await self.resolve(name, dns.rdatatype.A, **modified_kwargs) + return dns.resolver.HostAnswers.make(v4=v4) + elif family == socket.AF_INET6: + v6 = await self.resolve(name, dns.rdatatype.AAAA, **modified_kwargs) + return dns.resolver.HostAnswers.make(v6=v6) + elif family != socket.AF_UNSPEC: + raise NotImplementedError(f"unknown address family {family}") + + raise_on_no_answer = modified_kwargs.pop("raise_on_no_answer", True) + lifetime = modified_kwargs.pop("lifetime", None) + start = time.time() + v6 = await self.resolve( + name, + dns.rdatatype.AAAA, + raise_on_no_answer=False, + lifetime=self._compute_timeout(start, lifetime), + **modified_kwargs, + ) + # Note that setting name ensures we query the same name + # for A as we did for AAAA. (This is just in case search lists + # are active by default in the resolver configuration and + # we might be talking to a server that says NXDOMAIN when it + # wants to say NOERROR no data. + name = v6.qname + v4 = await self.resolve( + name, + dns.rdatatype.A, + raise_on_no_answer=False, + lifetime=self._compute_timeout(start, lifetime), + **modified_kwargs, + ) + answers = dns.resolver.HostAnswers.make( + v6=v6, v4=v4, add_empty=not raise_on_no_answer + ) + if not answers: + raise NoAnswer(response=v6.response) + return answers + + # pylint: disable=redefined-outer-name + + async def canonical_name(self, name: Union[dns.name.Name, str]) -> dns.name.Name: + """Determine the canonical name of *name*. + + The canonical name is the name the resolver uses for queries + after all CNAME and DNAME renamings have been applied. + + *name*, a ``dns.name.Name`` or ``str``, the query name. + + This method can raise any exception that ``resolve()`` can + raise, other than ``dns.resolver.NoAnswer`` and + ``dns.resolver.NXDOMAIN``. + + Returns a ``dns.name.Name``. + """ + try: + answer = await self.resolve(name, raise_on_no_answer=False) + canonical_name = answer.canonical_name + except dns.resolver.NXDOMAIN as e: + canonical_name = e.canonical_name + return canonical_name + + async def try_ddr(self, lifetime: float = 5.0) -> None: + """Try to update the resolver's nameservers using Discovery of Designated + Resolvers (DDR). If successful, the resolver will subsequently use + DNS-over-HTTPS or DNS-over-TLS for future queries. + + *lifetime*, a float, is the maximum time to spend attempting DDR. The default + is 5 seconds. + + If the SVCB query is successful and results in a non-empty list of nameservers, + then the resolver's nameservers are set to the returned servers in priority + order. + + The current implementation does not use any address hints from the SVCB record, + nor does it resolve addresses for the SCVB target name, rather it assumes that + the bootstrap nameserver will always be one of the addresses and uses it. + A future revision to the code may offer fuller support. The code verifies that + the bootstrap nameserver is in the Subject Alternative Name field of the + TLS certficate. + """ + try: + expiration = time.time() + lifetime + answer = await self.resolve( + dns._ddr._local_resolver_name, "svcb", lifetime=lifetime + ) + timeout = dns.query._remaining(expiration) + nameservers = await dns._ddr._get_nameservers_async(answer, timeout) + if len(nameservers) > 0: + self.nameservers = nameservers + except Exception: + pass + + +default_resolver = None + + +def get_default_resolver() -> Resolver: + """Get the default asynchronous resolver, initializing it if necessary.""" + if default_resolver is None: + reset_default_resolver() + assert default_resolver is not None + return default_resolver + + +def reset_default_resolver() -> None: + """Re-initialize default asynchronous resolver. + + Note that the resolver configuration (i.e. /etc/resolv.conf on UNIX + systems) will be re-read immediately. + """ + + global default_resolver + default_resolver = Resolver() + + +async def resolve( + qname: Union[dns.name.Name, str], + rdtype: Union[dns.rdatatype.RdataType, str] = dns.rdatatype.A, + rdclass: Union[dns.rdataclass.RdataClass, str] = dns.rdataclass.IN, + tcp: bool = False, + source: Optional[str] = None, + raise_on_no_answer: bool = True, + source_port: int = 0, + lifetime: Optional[float] = None, + search: Optional[bool] = None, + backend: Optional[dns.asyncbackend.Backend] = None, +) -> dns.resolver.Answer: + """Query nameservers asynchronously to find the answer to the question. + + This is a convenience function that uses the default resolver + object to make the query. + + See :py:func:`dns.asyncresolver.Resolver.resolve` for more + information on the parameters. + """ + + return await get_default_resolver().resolve( + qname, + rdtype, + rdclass, + tcp, + source, + raise_on_no_answer, + source_port, + lifetime, + search, + backend, + ) + + +async def resolve_address( + ipaddr: str, *args: Any, **kwargs: Any +) -> dns.resolver.Answer: + """Use a resolver to run a reverse query for PTR records. + + See :py:func:`dns.asyncresolver.Resolver.resolve_address` for more + information on the parameters. + """ + + return await get_default_resolver().resolve_address(ipaddr, *args, **kwargs) + + +async def resolve_name( + name: Union[dns.name.Name, str], family: int = socket.AF_UNSPEC, **kwargs: Any +) -> dns.resolver.HostAnswers: + """Use a resolver to asynchronously query for address records. + + See :py:func:`dns.asyncresolver.Resolver.resolve_name` for more + information on the parameters. + """ + + return await get_default_resolver().resolve_name(name, family, **kwargs) + + +async def canonical_name(name: Union[dns.name.Name, str]) -> dns.name.Name: + """Determine the canonical name of *name*. + + See :py:func:`dns.resolver.Resolver.canonical_name` for more + information on the parameters and possible exceptions. + """ + + return await get_default_resolver().canonical_name(name) + + +async def try_ddr(timeout: float = 5.0) -> None: + """Try to update the default resolver's nameservers using Discovery of Designated + Resolvers (DDR). If successful, the resolver will subsequently use + DNS-over-HTTPS or DNS-over-TLS for future queries. + + See :py:func:`dns.resolver.Resolver.try_ddr` for more information. + """ + return await get_default_resolver().try_ddr(timeout) + + +async def zone_for_name( + name: Union[dns.name.Name, str], + rdclass: dns.rdataclass.RdataClass = dns.rdataclass.IN, + tcp: bool = False, + resolver: Optional[Resolver] = None, + backend: Optional[dns.asyncbackend.Backend] = None, +) -> dns.name.Name: + """Find the name of the zone which contains the specified name. + + See :py:func:`dns.resolver.Resolver.zone_for_name` for more + information on the parameters and possible exceptions. + """ + + if isinstance(name, str): + name = dns.name.from_text(name, dns.name.root) + if resolver is None: + resolver = get_default_resolver() + if not name.is_absolute(): + raise NotAbsolute(name) + while True: + try: + answer = await resolver.resolve( + name, dns.rdatatype.SOA, rdclass, tcp, backend=backend + ) + assert answer.rrset is not None + if answer.rrset.name == name: + return name + # otherwise we were CNAMEd or DNAMEd and need to look higher + except (NXDOMAIN, NoAnswer): + pass + try: + name = name.parent() + except dns.name.NoParent: # pragma: no cover + raise NoRootSOA + + +async def make_resolver_at( + where: Union[dns.name.Name, str], + port: int = 53, + family: int = socket.AF_UNSPEC, + resolver: Optional[Resolver] = None, +) -> Resolver: + """Make a stub resolver using the specified destination as the full resolver. + + *where*, a ``dns.name.Name`` or ``str`` the domain name or IP address of the + full resolver. + + *port*, an ``int``, the port to use. If not specified, the default is 53. + + *family*, an ``int``, the address family to use. This parameter is used if + *where* is not an address. The default is ``socket.AF_UNSPEC`` in which case + the first address returned by ``resolve_name()`` will be used, otherwise the + first address of the specified family will be used. + + *resolver*, a ``dns.asyncresolver.Resolver`` or ``None``, the resolver to use for + resolution of hostnames. If not specified, the default resolver will be used. + + Returns a ``dns.resolver.Resolver`` or raises an exception. + """ + if resolver is None: + resolver = get_default_resolver() + nameservers: List[Union[str, dns.nameserver.Nameserver]] = [] + if isinstance(where, str) and dns.inet.is_address(where): + nameservers.append(dns.nameserver.Do53Nameserver(where, port)) + else: + answers = await resolver.resolve_name(where, family) + for address in answers.addresses(): + nameservers.append(dns.nameserver.Do53Nameserver(address, port)) + res = dns.asyncresolver.Resolver(configure=False) + res.nameservers = nameservers + return res + + +async def resolve_at( + where: Union[dns.name.Name, str], + qname: Union[dns.name.Name, str], + rdtype: Union[dns.rdatatype.RdataType, str] = dns.rdatatype.A, + rdclass: Union[dns.rdataclass.RdataClass, str] = dns.rdataclass.IN, + tcp: bool = False, + source: Optional[str] = None, + raise_on_no_answer: bool = True, + source_port: int = 0, + lifetime: Optional[float] = None, + search: Optional[bool] = None, + backend: Optional[dns.asyncbackend.Backend] = None, + port: int = 53, + family: int = socket.AF_UNSPEC, + resolver: Optional[Resolver] = None, +) -> dns.resolver.Answer: + """Query nameservers to find the answer to the question. + + This is a convenience function that calls ``dns.asyncresolver.make_resolver_at()`` + to make a resolver, and then uses it to resolve the query. + + See ``dns.asyncresolver.Resolver.resolve`` for more information on the resolution + parameters, and ``dns.asyncresolver.make_resolver_at`` for information about the + resolver parameters *where*, *port*, *family*, and *resolver*. + + If making more than one query, it is more efficient to call + ``dns.asyncresolver.make_resolver_at()`` and then use that resolver for the queries + instead of calling ``resolve_at()`` multiple times. + """ + res = await make_resolver_at(where, port, family, resolver) + return await res.resolve( + qname, + rdtype, + rdclass, + tcp, + source, + raise_on_no_answer, + source_port, + lifetime, + search, + backend, + ) -- cgit v1.2.3