Use the authoritative DNS server for PTR lookups

This commit is contained in:
Michael Kroes 2016-02-28 14:18:23 +01:00
parent f9ca440ce8
commit fc0f4ab7a9
1 changed files with 38 additions and 3 deletions

View File

@ -369,8 +369,8 @@ def check_primary_hostname_dns(domain, env, output, dns_domains, dns_zonefiles):
# Check reverse DNS matches the PRIMARY_HOSTNAME. Note that it might not be
# a DNS zone if it is a subdomain of another domain we have a zone for.
existing_rdns_v4 = query_dns(dns.reversename.from_address(env['PUBLIC_IP']), "PTR")
existing_rdns_v6 = query_dns(dns.reversename.from_address(env['PUBLIC_IPV6']), "PTR") if env.get("PUBLIC_IPV6") else None
existing_rdns_v4 = query_dns_ptr(dns.reversename.from_address(env['PUBLIC_IP']))
existing_rdns_v6 = query_dns_ptr(dns.reversename.from_address(env['PUBLIC_IPV6'])) if env.get("PUBLIC_IPV6") else None
if existing_rdns_v4 == domain and existing_rdns_v6 in (None, domain):
output.print_ok("Reverse DNS is set correctly at ISP. [%s%s]" % (my_ips, env['PRIMARY_HOSTNAME']))
elif existing_rdns_v4 == existing_rdns_v6 or existing_rdns_v6 is None:
@ -394,11 +394,38 @@ def check_primary_hostname_dns(domain, env, output, dns_domains, dns_zonefiles):
else:
output.print_error("""The DANE TLSA record for incoming mail (%s) is not correct. It is '%s' but it should be '%s'.
It may take several hours for public DNS to update after a change."""
% (tlsa_qname, tlsa25, tlsa25_expected))
% (tlsa_qname, tlsa25, tlsa25_expected))
# Check that the hostmaster@ email address exists.
check_alias_exists("Hostmaster contact address", "hostmaster@" + domain, env, output)
def query_dns_ptr(qname):
# Find the authoritative name server for the address using the default nameservers
resolver = dns.resolver.get_default_resolver()
nameserver = resolver.nameservers[0]
query = dns.message.make_query(qname, dns.rdatatype.PTR)
timeout = 5
response = dns.query.udp(query, nameserver, timeout)
returnCode = response.rcode()
# Check that we were able to query the dns for the authoritative server
if returnCode != dns.rcode.NOERROR:
return "[%s]" % dns.rcode.to_text(returnCode)
# If the current DNS server isn't the authority for this address use the one we find in the response
if len(response.authority) > 0:
rrset = response.authority[0]
else:
rrset = response.answer[0]
rr = rrset[0]
if rr.rdtype != dns.rdatatype.SOA:
authority = rr.target
nameserver = resolver.query(authority).rrset[0].to_text()
# Resolve the PTR record using the proper name server
return query_dns(qname, "PTR", at=nameserver)
def check_alias_exists(alias_name, alias, env, output):
mail_aliases = dict([(address, receivers) for address, receivers, *_ in get_mail_aliases(env)])
if alias in mail_aliases:
@ -918,6 +945,14 @@ if __name__ == "__main__":
elif sys.argv[1] == "--show-changes":
run_and_output_changes(env, pool)
elif sys.argv[1] == "--check-ptr":
out = ConsoleOutput()
# Get the list of domains we serve DNS zones for (i.e. does not include subdomains).
dns_zonefiles = dict(get_dns_zones(env))
dns_domains = set(dns_zonefiles)
check_primary_hostname_dns(env["PRIMARY_HOSTNAME"], env, out, dns_domains, dns_zonefiles)
elif sys.argv[1] == "--check-primary-hostname":
# See if the primary hostname appears resolvable and has a signed certificate.
domain = env['PRIMARY_HOSTNAME']