From grodriguez@inria.fr Tue Nov 07 15:09:46 1995
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!inria!grodriguez
From: grodriguez@inria.fr (Göran Rodríguez)
Newsgroups: comp.sys.m68k
Subject: Discussion: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Nov07.150946.7627@inria.fr>
Date: Tue, 07 Nov 1995 15:09:46 GMT
Organization: INRIA Rocquencourt
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Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board.

This indicates socket U14 held a cryptographic S-box lookup table for decrypting the Stardust keystream.
Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14.

Did Marcus take the decryption EPROM with him when he left the lab?

-- 
Göran Rodríguez -- INRIA Rocquencourt
"Tape doesn't lie at 02:14. Ears do."

From dlarsson@delphi.com Wed Nov 08 16:52:46 1995
Path: ashpoly!cascade!mxgate!coyoacan!delphi!dlarsson
From: dlarsson@delphi.com (Dong-hyun Larsson)
Newsgroups: comp.sys.m68k
Subject: Re: Discussion: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Nov08.165246.8018@delphi.com>
Date: Wed, 08 Nov 1995 16:52:46 GMT
References: <1995Nov07.150946.7627@inria.fr>
Organization: Delphi Internet Services
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In article <1995Nov07.150946.7627@inria.fr>, grodriguez@inria.fr (Göran Rodríguez) writes:
> Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board.

Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984.

-- 
Dong-hyun Larsson -- Delphi Internet Services
"They will send a copy in my place."