Re: Tcpdump and 3des packets

From: All Mail (allmail@jeff.ath.cx)
Date: 09/21/01 

Date: Fri, 21 Sep 2001 09:32:34 -0400 (EDT)
From: All Mail <allmail@jeff.ath.cx>
To: <focus-linux@securityfocus.com>
Subject: Re: Tcpdump and 3des packets
Message-ID: <20010921093051.S7404-100000@jeff.ath.cx>

On Mon, 17 Sep 2001, Anthony Baxter wrote:

>
>
> has anybody been able to use tcpdump to decrypt 3des packets, i am trying to
> vpn between freeswan and vpn 1, i need to look at these packets but tcpdump
> WILLNOT compile with crypto support
>
> mandrake 8.0
>
> this is my first posting, and i not even sure this is the right place to
> post so please forgive me.
>
> What are my options are there other sniffers that can decode 3des ???
>
>
> many thanks
>
> anthony
>

DES is a one way hash, as is 3DES. It cannot be "decrypted". The only
way to guess DES/3DES keys is to brute force them.

Jeff

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