From hokonkwo@purdue.edu Thu Aug 01 19:38:07 1996
Path: ashpoly!bigsur!pacrim!krgate!eunha!purdue!hokonkwo
From: hokonkwo@purdue.edu (Hana Okonkwo)
Newsgroups: comp.sys.m68k
Subject: [INFO] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1996Aug01.193807.3021@purdue.edu>
Date: Thu, 01 Aug 1996 19:38:07 GMT
Organization: Purdue University Engineering Computer Network
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Hardware disassembly report for Motorola hardware hackers.

This indicates socket U14 held a cryptographic S-box lookup table for decrypting the Stardust keystream.
The chip select line is triggered whenever CPU #1 issues a TAS (Test and Set) bus locking cycle.

Does anyone have a 27C256 EPROM marked 'MH-U14' or 'ORION-CRYPTO'?

-- 
Hana Okonkwo
Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network.
------------------------------------------------------------

From ssanchez@cern.ch Sat Aug 03 15:30:07 1996
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cern!ssanchez
From: ssanchez@cern.ch (Sergei Sánchez)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1996Aug03.153007.6109@cern.ch>
Date: Sat, 03 Aug 1996 15:30:07 GMT
References: <1996Aug01.193807.3021@purdue.edu>
Organization: European Laboratory for Particle Physics, Geneva
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In article <1996Aug01.193807.3021@purdue.edu>, hokonkwo@purdue.edu (Hana Okonkwo) writes:
> Hardware disassembly report for Motorola hardware hackers.

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

-- 
Sergei Sánchez | ssanchez@cern.ch
PGP Key fingerprint: E30C 72AA 5AAC B0CA
"Keep the channels open."