def _lookup(self, name, cls, type, timeout=None):
"""
Determine a response to a particular DNS query.
@param name: The name which is being queried and for which to lookup a
response.
@type name: L{bytes}
@param cls: The class which is being queried. Only I{IN} is
implemented here and this value is presently disregarded.
@type cls: L{int}
@param type: The type of records being queried. See the types defined
in L{twisted.names.dns}.
@type type: L{int}
@param timeout: All processing is done locally and a result is
available immediately, so the timeout value is ignored.
@return: A L{Deferred} that fires with a L{tuple} of three sets of
response records (to comprise the I{answer}, I{authority}, and
I{additional} sections of a DNS response) or with a L{Failure} if
there is a problem processing the query.
"""
cnames = []
results = []
authority = []
additional = []
default_ttl = max(self.soa[1].minimum, self.soa[1].expire)
domain_records = self.records.get(name.lower())
if domain_records:
for record in domain_records:
if record.ttl is not None:
ttl = record.ttl
else:
ttl = default_ttl
if (record.TYPE == dns.NS and
name.lower() != self.soa[0].lower()):
# NS record belong to a child zone: this is a referral. As
# NS records are authoritative in the child zone, ours here
# are not. RFC 2181, section 6.1.
authority.append(
dns.RRHeader(
name, record.TYPE, dns.IN, ttl, record, auth=False
)
)
elif record.TYPE == type or type == dns.ALL_RECORDS:
results.append(
dns.RRHeader(
name, record.TYPE, dns.IN, ttl, record, auth=True
)
)
if record.TYPE == dns.CNAME:
cnames.append(
dns.RRHeader(
name, record.TYPE, dns.IN, ttl, record, auth=True
)
)
if not results:
results = cnames
# Sort of https://tools.ietf.org/html/rfc1034#section-4.3.2 .
# See https://twistedmatrix.com/trac/ticket/6732
additionalInformation = self._additionalRecords(
results, authority, default_ttl)
if cnames:
results.extend(additionalInformation)
else:
additional.extend(additionalInformation)
if not results and not authority:
# Empty response. Include SOA record to allow clients to cache
# this response. RFC 1034, sections 3.7 and 4.3.4, and RFC 2181
# section 7.1.
authority.append(
dns.RRHeader(
self.soa[0], dns.SOA, dns.IN, ttl, self.soa[1],
auth=True
)
)
return defer.succeed((results, authority, additional))
else:
if dns._isSubdomainOf(name, self.soa[0]):
# We may be the authority and we didn't find it.
# XXX: The QNAME may also be in a delegated child zone. See
# #6581 and #6580
return defer.fail(
failure.Failure(dns.AuthoritativeDomainError(name))
)
else:
# The QNAME is not a descendant of this zone. Fail with
# DomainError so that the next chained authority or
# resolver will be queried.
return defer.fail(failure.Failure(error.DomainError(name)))
def _lookup(self, name, cls, type, timeout=None):
"""
Determine a response to a particular DNS query.
@param name: The name which is being queried and for which to lookup a
response.
@type name: L{bytes}
@param cls: The class which is being queried. Only I{IN} is
implemented here and this value is presently disregarded.
@type cls: L{int}
@param type: The type of records being queried. See the types defined
in L{twisted.names.dns}.
@type type: L{int}
@param timeout: All processing is done locally and a result is
available immediately, so the timeout value is ignored.
@return: A L{Deferred} that fires with a L{tuple} of three sets of
response records (to comprise the I{answer}, I{authority}, and
I{additional} sections of a DNS response) or with a L{Failure} if
there is a problem processing the query.
"""
cnames = []
results = []
authority = []
additional = []
default_ttl = max(self.soa[1].minimum, self.soa[1].expire)
domain_records = self.records.get(name.lower())
if domain_records:
for record in domain_records:
if record.ttl is not None:
ttl = record.ttl
else:
ttl = default_ttl
if (record.TYPE == dns.NS and
name.lower() != self.soa[0].lower()):
# NS record belong to a child zone: this is a referral. As
# NS records are authoritative in the child zone, ours here
# are not. RFC 2181, section 6.1.
authority.append(
dns.RRHeader(
name, record.TYPE, dns.IN, ttl, record, auth=False
)
)
elif record.TYPE == type or type == dns.ALL_RECORDS:
results.append(
dns.RRHeader(
name, record.TYPE, dns.IN, ttl, record, auth=True
)
)
if record.TYPE == dns.CNAME:
cnames.append(
dns.RRHeader(
name, record.TYPE, dns.IN, ttl, record, auth=True
)
)
if not results:
results = cnames
# Sort of https://tools.ietf.org/html/rfc1034#section-4.3.2 .
# See https://twistedmatrix.com/trac/ticket/6732
additionalInformation = self._additionalRecords(
results, authority, default_ttl)
if cnames:
results.extend(additionalInformation)
else:
additional.extend(additionalInformation)
if not results and not authority:
# Empty response. Include SOA record to allow clients to cache
# this response. RFC 1034, sections 3.7 and 4.3.4, and RFC 2181
# section 7.1.
authority.append(
dns.RRHeader(
self.soa[0], dns.SOA, dns.IN, ttl, self.soa[1],
auth=True
)
)
return defer.succeed((results, authority, additional))
else:
if dns._isSubdomainOf(name, self.soa[0]):
# We may be the authority and we didn't find it.
# XXX: The QNAME may also be in a delegated child zone. See
# #6581 and #6580
return defer.fail(
failure.Failure(dns.AuthoritativeDomainError(name))
)
else:
# The QNAME is not a descendant of this zone. Fail with
# DomainError so that the next chained authority or
# resolver will be queried.
return defer.fail(failure.Failure(error.DomainError(name)))
def _lookup(self, name, cls, type, timeout = None):
cnames = []
results = []
authority = []
additional = []
default_ttl = max(self.soa[1].minimum, self.soa[1].expire)
domain_records = self.records.get(name.lower())
if domain_records:
for record in domain_records:
if record.ttl is not None:
ttl = record.ttl
else:
ttl = default_ttl
if record.TYPE == dns.NS and name.lower() != self.soa[0].lower():
# NS record belong to a child zone: this is a referral. As
# NS records are authoritative in the child zone, ours here
# are not. RFC 2181, section 6.1.
authority.append(
dns.RRHeader(name, record.TYPE, dns.IN, ttl, record, auth=False)
)
elif record.TYPE == type or type == dns.ALL_RECORDS:
results.append(
dns.RRHeader(name, record.TYPE, dns.IN, ttl, record, auth=True)
)
if record.TYPE == dns.CNAME:
cnames.append(
dns.RRHeader(name, record.TYPE, dns.IN, ttl, record, auth=True)
)
if not results:
results = cnames
for record in results + authority:
section = {dns.NS: additional, dns.CNAME: results, dns.MX: additional}.get(record.type)
if section is not None:
n = str(record.payload.name)
for rec in self.records.get(n.lower(), ()):
if rec.TYPE == dns.A:
section.append(
dns.RRHeader(n, dns.A, dns.IN, rec.ttl or default_ttl, rec, auth=True)
)
if not results and not authority:
# Empty response. Include SOA record to allow clients to cache
# this response. RFC 1034, sections 3.7 and 4.3.4, and RFC 2181
# section 7.1.
authority.append(
dns.RRHeader(self.soa[0], dns.SOA, dns.IN, ttl, self.soa[1], auth=True)
)
return defer.succeed((results, authority, additional))
else:
if dns._isSubdomainOf(name, self.soa[0]):
# We may be the authority and we didn't find it.
# XXX: The QNAME may also be a in a delegated child zone. See
# #6581 and #6580
return defer.fail(failure.Failure(dns.AuthoritativeDomainError(name)))
else:
# The QNAME is not a descendant of this zone. Fail with
# DomainError so that the next chained authority or
# resolver will be queried.
return defer.fail(failure.Failure(error.DomainError(name)))