Re: DNS RRTYPEs, the difficulty with


In message <3503462.Q2aCvq3QGU@scott-latitude-e6320>, Scott Kitterman writes:

On Monday, February 27, 2012 12:32:11 PM Paul Hoffman wrote:

On Feb 27, 2012, at 11:57 AM, Murray S. Kucherawy wrote:

-----Original Message-----
From: ietf-bounces(_at_)ietf(_dot_)org 
[mailto:ietf-bounces(_at_)ietf(_dot_)org] On Behalf
Of Patrik F=E4ltstr=F6m Sent: Monday, February 27, 2012 11:43 AM
To: Hector
Cc: ietf(_at_)ietf(_dot_)org
Subject: Re: DNS RRTYPEs, the difficulty with
=

I have not heard anything else than arguments in RFC5507 against
reusing same RRType for many different kind of use.
=

5507 Design Choices When Expanding the DNS. IAB, P. Faltstrom, Ed., R.
=

    Austein, Ed., P. Koch, Ed.. April 2009. (Format: TXT=3D44045
    bytes)
    (Status: INFORMATIONAL)
=

So, still, no, you should not reuse TXT. You should have your own
RRType. Other choices makes your design very complex.
=

Yes, many people will still disagree with me, using arguments I do not
agree with...

The conclusion of Section 3.5 of that document doesn't really address
the first bullet in the same section, namely that the user interface by
which the new RRType would get added to a zone often doesn't support
doing so.  That's turned out to be a serious problem with, for example,
the deployment of the SPF record (RRType 99).

Which user interfaces are people using to add RRtype 99? If you are having
them edit zone files by hand well, yes, that would not work real well for
SPF. If there is a simple tool that takes the needed information and crea=

te

a standard-formatted record that can be copy-and-pasted, it would make use
of that RRtype much easier. If no such tool exists, I propose that it can
be created easily.


We've published a script to take a Type TXT SPF record and give a Type SPF =

output as part of the pyspf library since very shortly after Type SPF was =

assigned.  It's been around for years, so the lack of that type of tool isn=
't =

an issue.

Scott K


My user interface is "vi".

RFC 4408 April 2006

revision 1.1
date: 2005-07-14 16:46:44 +1000;  author: marka;  state: Exp;
branches:  1.1.2;
1892.   [func]          Support for SPF rdata type. [RT #15033]

It was first available in BIND 9.4.0 (Feb 2007) earlier still if
you were willing to run alpha/beta/rc.

OS vendors could have supplied it earlier.

cp lib/dns/rdata/generic/txt_16.c lib/dns/rdata/generic/spf_19.c
cp lib/dns/rdata/generic/txt_16.h lib/dns/rdata/generic/spf_19.h

s/TXT/SPF/
s/txt/spf/
s/16/99/

make clean
make

You don't even have to touch a Makefile.   After that all the tools
that come with BIND support SPF.

If I remember correctly someone did something like that and made it
available.  Its definitely been done for a number of new types.

Mark
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka(_at_)isc(_dot_)org
_______________________________________________
Ietf mailing list
Ietf(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/ietf