Re: [dnsext] New RRtype "KREALM" in draft-vanrein-dnstxt-krb1-02.txt

Rick van Rein <> Fri, 11 September 2015 09:58 UTC

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Date: Fri, 11 Sep 2015 11:58:36 +0200
From: Rick van Rein <>
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Subject: Re: [dnsext] New RRtype "KREALM" in draft-vanrein-dnstxt-krb1-02.txt
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Hi Tony / list,

> Why not use the HINFO RDATA format to store the tag/value pairs? No need
> for embedding the sequence in the RDATA since RRsets already provide that.
> No need to embed a version number since RRtypes provide that.

Interesting suggestion, I wasn't aware of this possibility.  Indeed, a binary string with prefixed length should work, I see that escaping has been arranged in RFC 1035 and 255 data bytes isn't a strange upper limit for a string.

I can't seem to find a tag/value definition format for HINFO though; can you give me a reference?  I wanted to avoid requesting a parser that specific, but if it's already there then it's certainly a good idea.

Note that ASN.1 is a home game to Kerberos, so from that perspective the wire format makes a lot of sense, I think.  You are not proposing to change the wire format, right?