[nsd-users] NSD compressing RP content

Peter van Dijk peter.van.dijk at netherlabs.nl
Thu Mar 7 14:37:24 UTC 2013


Hello Matthijs,

3597 also deals with it by saying nsd MUST NOT compress these types.

The harm is in NSD ignoring a MUST NOT, relying on recursors to implement a SHOULD. This should, of course, be the other way around.

Naturally, PowerDNS now honors the SHOULD, as interoperability is key.

And yes, my request extends to all types not mentioned in 1035, as mandated by 3597.

Kind regards,
Peter van Dijk

On Mar 4, 2013, at 16:00 , Matthijs Mekking wrote:

> Hi Peter,
> 
> Sure we can send RP domain names uncompressed from now on.
> 
> I can understand your reasoning: RP is not defined in RFC 1035, hence it
> is not allowed to use *name* compression.
> 
> However, RP (and AFSDB and RT) are defined in RFC 1183, and at the time
> that that specification was written, name compression was allowed for
> these records (not explicitly mentioned in the specification). RFC3597
> deals with this saying that *receiving* servers should decompress domain
> names in these RRs.
> 
> So I fail to see where things might be harmful. PowerDNS should have no
> problem if it implements RFC3597, as RP should be decompressed, as BIND
> and Unbound does too (Unbound actually decompresses all domain names of
> known RR types).
> 
> Also, I assume your request is not limited to RP, but is also for AFSDB
> and RT.
> 
> Best regards,
>  Matthijs
> 
> 
> On 03/01/2013 03:22 PM, Peter van Dijk wrote:
>> Hello,
>> 
>> while investigating a report from Jan-Piet Mens (resulting in http://wiki.powerdns.com/trac/changeset/3109), we discovered that NSD (both 3.2.15 and 4.0.0b4) compresses labels in RP content. As far as I can see, this is not allowed by RFC3597 section 4 paragraph 1/2.
>> 
>> PowerDNS Recursor, like Unbound and BIND, now deals with this as 3597 section 4 paragraph 4 says we SHOULD. Nevertheless, it would be great if NSD could honor the MUST NOT in paragraph 2.
>> 
>> Kind regards,
>> 
> 
> 

-- 
Netherlabs Computer Consulting BV - http://www.netherlabs.nl/





More information about the nsd-users mailing list