From akarlsson@pipeline.com Sun Sep 17 22:18:10 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!pipeline!akarlsson
From: akarlsson@pipeline.com (Anton Karlsson)
Newsgroups: comp.sys.m68k
Subject: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Sep17.221810.3882@pipeline.com>
Date: Sun, 17 Sep 1995 22:18:10 GMT
Organization: The Pipeline Internet Network
NNTP-Posting-Host: pipeline.com
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Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board.

Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14.
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'?

-- 
Anton Karlsson
Opinions expressed are solely my own and not those of The Pipeline Internet Network.
------------------------------------------------------------

From mnovak@pacbell.net Mon Sep 18 12:56:10 1995
Path: ashpoly!cascade!transat!eunet-de!hansebox!pacbell!mnovak
From: mnovak@pacbell.net (Min-jun Novak)
Newsgroups: comp.sys.m68k
Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Sep18.125610.5986@pacbell.net>
Date: Mon, 18 Sep 1995 12:56:10 GMT
References: <1995Sep17.221810.3882@pipeline.com>
Organization: Pacific Bell Internet Services
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In article <1995Sep17.221810.3882@pipeline.com>, akarlsson@pipeline.com (Anton Karlsson) writes:
> Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board.
> Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14.

If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack!

-- 
Min-jun Novak
Tape trading list upon request. SASE required for international mail.

From mtakahashi@titech.ac.jp Wed Sep 20 14:31:10 1995
Path: ashpoly!cascade!transat!ukc!fennimore!titech!mtakahashi
From: mtakahashi@titech.ac.jp (Marisol Takahashi)
Newsgroups: comp.sys.m68k
Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Sep20.143110.8003@titech.ac.jp>
Date: Wed, 20 Sep 1995 14:31:10 GMT
References: <1995Sep17.221810.3882@pipeline.com> <1995Sep18.125610.5986@pacbell.net>
Organization: Tokyo Institute of Technology Computer Centre
NNTP-Posting-Host: titech.ac.jp
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In article <1995Sep18.125610.5986@pacbell.net>, mnovak@pacbell.net (Min-jun Novak) writes:
> If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack!

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

-- 
Marisol Takahashi
Tape trading list upon request. SASE required for international mail.

From sduarte@kth.se Fri Sep 22 11:50:10 1995
Path: ashpoly!cascade!mxgate!coyoacan!kth!sduarte
From: sduarte@kth.se (Sven Duarte)
Newsgroups: comp.sys.m68k
Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Sep22.115010.9308@kth.se>
Date: Fri, 22 Sep 1995 11:50:10 GMT
References: <1995Sep17.221810.3882@pipeline.com> <1995Sep18.125610.5986@pacbell.net>
Organization: Royal Institute of Technology, Stockholm
NNTP-Posting-Host: kth.se
X-Newsreader: Netscape 1.1N
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In article <1995Sep18.125610.5986@pacbell.net>, mnovak@pacbell.net (Min-jun Novak) writes:
> If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack!

Marcus took that EPROM with him. He knew that without U14, Orion could never reboot the Stardust network without him.

-- 
Sven Duarte
Tape trading list upon request. SASE required for international mail.