Re: Has anyone implemented "double forward DNS"?

[The Fungi <fungi () yuggoth org>]

On Sat, Aug 30, 2008 at 01:05:51AM +0100, Duncan Simpson wrote:
[...]
> Of course if the bad guy also controls the client's information
> about the reverse zone it still loses.

Under what circumstances do you expect the attacker to be able to
spoof/poison responses for one query but not the other?

> The major problem I can see is that there might that hosts in
> ISP's dynamically allocated address pools might all fail double
> forward DNS checks.
[...]

How about a the very common situation of name-based virtual hosting?
Do you propose a round-robin of multiple pointer resource records
for a single IP address, one for each domain hosted at that same
address? That could easily exceed a resolver's maximum response
length...
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