[dns-operations] Spurious (?) DNSSEC SERVFAIL with some (?) versions of BIND for one domain?

Mark Andrews marka at isc.org
Wed Mar 10 22:42:37 UTC 2021


And has anyone reported this to them?

> On 11 Mar 2021, at 09:37, Mark Andrews <marka at isc.org> wrote:
> 
> So who is correctly rejecting DS at top of zone at load time?  There is no way
> to query for this RRset.
> 
>> On 11 Mar 2021, at 06:29, Peter van Dijk <peter.van.dijk at powerdns.com> wrote:
>> 
>> On Wed, 2021-03-10 at 16:44 +0000, Matthew Richardson wrote:
>>>      9qbq9dd8lt1gvge9gdmb5m0o13iuqeqt.prv.se: type NSEC3, class IN
>>>>          Name: 9qbq9dd8lt1gvge9gdmb5m0o13iuqeqt.prv.se
>> 
>> Which is the NSEC3 hash of 'prv.se.',
>> 
>>>>          Type: NSEC3 (50)
>>>>          Class: IN (0x0001)
>>>>          Time to live: 3600
>>>>          Data length: 43
>>>>          Hash algorithm: SHA-1 (1)
>>>>          NSEC3 flags: 0
>>>>              .... ...0 = NSEC3 Opt-out flag: Additional insecure delegations forbidden
>>>>          NSEC3 iterations: 50
>>>>          Salt length: 8
>>>>          Salt value: 33e9285ab62c0803
>>>>          Hash length: 20
>>>>          Next hashed owner: 4f848f41f3884a3fc412e821e031cdd8b9a48eca
>>>>          RR type in bit map: A (Host Address)
>>>>          RR type in bit map: NS (authoritative Name Server)
>>>>          RR type in bit map: SOA (Start Of a zone of Authority)
>>>>          RR type in bit map: MX (Mail eXchange)
>>>>          RR type in bit map: TXT (Text strings)
>>>>          RR type in bit map: DS(Delegation Signer)
>> 
>> which apparently has a DS at the apex of the child zone, which is
>> somewhere between 'useless' and 'wrong'.
>> 
>>>>          RR type in bit map: RRSIG
>>>>          RR type in bit map: DNSKEY
>>>>          RR type in bit map: NSEC3PARAM
>> 
>> Combined with
>> 
>>> 10-Mar-2021 16:20:11.606 dnssec: info: validating _dmarc.prv.se/TXT:
>> bad cache hit (_dmarc.prv.se/DS)
>> 
>> My vague suspicion is that BIND is flagging this as an impossible
>> situation, because a DS should live in the parent, and only in the
>> parent.
>> 
>> I recall isc.org 'recently' had a DS at the apex of the child zone; I
>> wonder if after ISC removed that, they made BIND, as a validator,
>> stricter about it when detected.
>> 
>> Kind regards,
>> -- 
>> Peter van Dijk
>> PowerDNS.COM BV - https://www.powerdns.com/
>> 
>> _______________________________________________
>> dns-operations mailing list
>> dns-operations at lists.dns-oarc.net
>> https://lists.dns-oarc.net/mailman/listinfo/dns-operations
> 
> -- 
> Mark Andrews, ISC
> 1 Seymour St., Dundas Valley, NSW 2117, Australia
> PHONE: +61 2 9871 4742              INTERNET: marka at isc.org
> 

-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742              INTERNET: marka at isc.org





More information about the dns-operations mailing list