Autor: Marc Perkel Data: CC: exim-users Assunto: Re: [exim] At what point is the initial connect greeting sent?
Tony Finch wrote:
>On Fri, 25 Feb 2005, Matthew Newton wrote:
>
>
>>On Fri, Feb 25, 2005 at 07:56:53AM -0800, Marc Perkel wrote:
>>
>>
>>>If I want to put an initial 2 second delay in the initial creeting that
>>>is sent before the user sends HELO - where would I put it? Trying to
>>>trap spammers who send data two quickly without waiting for the proper
>>>server responses.
>>>
>>>
>>Interesting idea...
>>
>>
>
>It works fairly well, catching about 10% of junk. We add a conditional
>delay both before the inital banner and before the response to HELO. We
>don't bother with extra delays after RCPT because RCPT is not a
>synchronization point. We could perhaps add a delay in the predata ACL
>which is the only remaining synchronization point where we don't impose a
>penalty (though the various checks in the RCPT ACLs may be enough by
>themselves). See section 3.7 of my paper for details:
>
>http://www.cus.cam.ac.uk/~fanf2/hermes/doc/talks/2005-02-eximconf/paper.pdf >
>Tony.
>
> Yeah - it does seem to be working somewhat.