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

Rick van Rein <rick@openfortress.nl> Fri, 11 September 2015 11:14 UTC

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Date: Fri, 11 Sep 2015 13:14:34 +0200
From: Rick van Rein <rick@openfortress.nl>
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To: Tony Finch <dot@dotat.at>
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Subject: Re: [dnsext] New RRtype "KREALM" in draft-vanrein-dnstxt-krb1-02.txt
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Hi Tony,

Thanks for thinking along!

> I was thinking
>
> @ KREALM "realm" "EXAMPLE.COM"
> KREALM "realm" "EXAMPLE.ORG"
> KREALM "admin" "carl"
> KREALM "admin" "mary"
> KREALM "service" "HTTP"
> KREALM "service" "imap"

That would make it impossible to express everything that is desired. 
The level of alternation that you are using here has been reserved for
independent statements; the combined tag=value statements form a
cross-product; for example all the realms mentioned combine with all the
admins mentioned in the same RDATA portion.  If another realm has
another admin set it will be specified in a separate KREALM.

This is why I end up with a variable list of tag=value assignments under
one KREALM, and as explained that strikes me as an oddball solution in
DNS.  Do you agree?

Note that more base64 data is incorporated into DNS already, for
instance certificates (where, I admit, there is no choice due to the
tightness of the signatures).

-Rick