On Sun, Jul 04, 2004 at 07:40:51PM +0100, Mark Powell wrote:
>   Had some dialup joker today, opening 45 smtp connections and doing
> nothing on them, but a NOOP every 30s. Four hours later they were all
> still there, until I killed them and blocked the IP.
>   Can we have the possibility of a noop handler, so a plugin could prevent
> this?

Hm.  While we might as well have a no-op hook, the attacker could have
staged the same sort of attack with a gradual cycle of mail/rcpt/rset
commands.  A better countermeasure for this one would be a per-client
max-connections limit.  Won't do much against a zombie attack, but it'd
deal with this sort.

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