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From: Darren Reed <avalon@coombs.anu.edu.au>
Subject: Re: ipdivert & masqd
To: eivind@dimaga.com (Eivind Eklund)
Date: Thu, 30 Jan 1997 07:37:46 +1100 (EDT)
Cc: brian@awfulhak.demon.co.uk, archie@whistle.com, hackers@FreeBSD.ORG,
        ari.suutari@ps.carel.fi, cmott@srv.net
In-Reply-To: <3.0.32.19970129155305.00ab11a0@dimaga.com> from "Eivind Eklund" at Jan 29, 97 03:53:06 pm
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In some mail from Eivind Eklund, sie said:
> 
> For the IRC DCC case (which I'll hopefully bring to testing point tomorrow
> - any volunteers?) the expansion can be by 11 characters for each DCC hook
> in a PRIVMSG, totalling max (payload size)*(4/3), ie expanding to 7/3 the
> original size for a constructed nasty case.  This has bounds-checking,
> though, and will not do overwrites.  Still, extra buffer-space do make it
> work more reliably.

But anything after the 512th data byte in the TCP payload will be ignored,
so if your message is 512 bytes long, contains a DCC request in it,
information will be lost that the sender is not aware about (this assumes
the packet is just one IRC message) if the payload size must increase as
a result.

It is a *much* better idea to redirect IRC to a local TCP port and process
it using a proxy agent.  Same could also be said for FTP.

Darren