def get_query_answer(self, name, rdtype):
'''
return
- rdataset from query answer
'''
origin = dns.name.Name(self.zonename.split('.'))
qname = name.derelativize(origin)
#print('name={}, type={} to NS={}'.format(qname.to_text(), dns.rdatatype.to_text(rdtype), self.resolver.nameservers) )
if rdtype == dns.rdatatype.NS:
pass
#ans = self.resolver.query(qname, rdtype, raise_on_no_answer=False)
try:
ans = self.resolver.query(qname, rdtype)
except Exception as err:
if rdtype == dns.rdatatype.NS:
ans = self.resolver.query(qname,
rdtype,
raise_on_no_answer=False)
return ans.response.authority[0]
elif rdtype == dns.rdatatype.A:
ans = self.resolver.query(qname,
rdtype,
raise_on_no_answer=False)
for ad in ans.response.additional:
if ad.name == qname:
#print('{} vs {}'.format(qname, ad.name))
return ad
raise Exception
raise Exception
return ans.rrset
def _rrsig_labels(name, origin):
"""
Get label count of the given dns name as required for RRSIG labels field.
See RFC-4034, section 3.1.3. for details.
"""
labels = [x for x in name.derelativize(origin).labels
if len(x) and x != '*']
return len(labels)
def rdata_to_text(self, origin, name, rdataset, rdata):
'a text formatter like "www.myexample.com 1800 IN A 10.20.30.60"'
name_txt = name.derelativize(origin).to_text()
ttl = rdataset.ttl
cls_txt = dns.rdataclass.to_text(rdataset.rdclass)
rtype_txt = dns.rdatatype.to_text(rdataset.rdtype)
record_txt = rdata.to_text()
return '{} {} {} {} {}'.format(name_txt, ttl, cls_txt, rtype_txt,
record_txt)
def echo_zone(self):
'''
for debug use
'''
print('Zone: {}'.format(self.zone.origin))
print('===============')
for name, node in self.zone.nodes.items():
for rdataset in node.rdatasets:
for d in rdataset:
print('Name={}, d={}'.format(
name.derelativize(self.zone.origin), d))
def _validate_name(self, name: dns.name.Name) -> dns.name.Name:
if name.is_absolute():
if self.origin is None:
# This should probably never happen as other code (e.g.
# _rr_line) will notice the lack of an origin before us, but
# we check just in case!
raise KeyError("no zone origin is defined")
if not name.is_subdomain(self.origin):
raise KeyError("name is not a subdomain of the zone origin")
if self.zone.relativize:
name = name.relativize(self.origin)
elif not self.zone.relativize:
# We have a relative name in a non-relative zone, so derelativize.
if self.origin is None:
raise KeyError("no zone origin is defined")
name = name.derelativize(self.origin)
return name
def _validate_name(self, name):
if isinstance(name, str):
name = dns.name.from_text(name, None)
elif not isinstance(name, dns.name.Name):
raise KeyError("name parameter must be convertible to a DNS name")
if name.is_absolute():
if not name.is_subdomain(self.origin):
raise KeyError(
"name parameter must be a subdomain of the zone origin")
if self.relativize:
name = name.relativize(self.origin)
elif not self.relativize:
# We have a relative name in a non-relative zone, so derelativize.
if self.origin is None:
raise KeyError('no zone origin is defined')
name = name.derelativize(self.origin)
return name
def _validate_name(self, name: Union[dns.name.Name, str]) -> dns.name.Name:
if isinstance(name, str):
name = dns.name.from_text(name, None)
elif not isinstance(name, dns.name.Name):
raise KeyError("name parameter must be convertible to a DNS name")
if name.is_absolute():
if self.origin is None:
# This should probably never happen as other code (e.g.
# _rr_line) will notice the lack of an origin before us, but
# we check just in case!
raise KeyError("no zone origin is defined")
if not name.is_subdomain(self.origin):
raise KeyError(
"name parameter must be a subdomain of the zone origin")
if self.relativize:
name = name.relativize(self.origin)
elif not self.relativize:
# We have a relative name in a non-relative zone, so derelativize.
if self.origin is None:
raise KeyError("no zone origin is defined")
name = name.derelativize(self.origin)
return name