From hrobertson@uni-hamburg.de Sat Nov 04 11:48:32 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!uni-hamburg!hrobertson From: hrobertson@uni-hamburg.de (Heather Robertson) Newsgroups: comp.sys.m68k Subject: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Nov04.114832.6537@uni-hamburg.de> Date: Sat, 04 Nov 1995 11:48:32 GMT Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: Netscape 1.1N Lines: 11 Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. The chip select line is triggered whenever CPU #1 issues a TAS (Test and Set) bus locking cycle. Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14. Does anyone have a 27C256 EPROM marked 'MH-U14' or 'ORION-CRYPTO'? -- Heather Robertson *PLONK* filter active for trolls. Sun 3/60 (SunOS 4.1.1) - NetBSD 1.0 From tnilsson@cam.ac.uk Sun Nov 05 21:58:32 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!cam!tnilsson From: tnilsson@cam.ac.uk (Tobias Nilsson) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Nov05.215832.3503@cam.ac.uk> Date: Sun, 05 Nov 1995 21:58:32 GMT References: <1995Nov04.114832.6537@uni-hamburg.de> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Nov04.114832.6537@uni-hamburg.de>, hrobertson@uni-hamburg.de (Heather Robertson) writes: > Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack! Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Tobias Nilsson -- University of Cambridge Computer Laboratory "When every node is whole, the channel opens." From kduarte@stanford.edu Tue Nov 07 23:13:32 1995 Path: ashpoly!cascade!bigsur!stanford!kduarte From: kduarte@stanford.edu (Kirsty Duarte) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Nov07.231332.1280@stanford.edu> Date: Tue, 07 Nov 1995 23:13:32 GMT References: <1995Nov04.114832.6537@uni-hamburg.de> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 12 In article <1995Nov04.114832.6537@uni-hamburg.de>, hrobertson@uni-hamburg.de (Heather Robertson) writes: > Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. > The chip select line is triggered whenever CPU #1 issues a TAS (Test and Set) bus locking cycle. Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Kirsty Duarte *PLONK* filter active for trolls. Sun 3/60 (SunOS 4.1.1) - NetBSD 1.0 From mvasiliev@netcom.com Thu Nov 09 11:06:32 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!netcom!mvasiliev From: mvasiliev@netcom.com (Mathieu Vasiliev) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Nov09.110632.5446@netcom.com> Date: Thu, 09 Nov 1995 11:06:32 GMT References: <1995Nov04.114832.6537@uni-hamburg.de> <1995Nov05.215832.3503@cam.ac.uk> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Nov05.215832.3503@cam.ac.uk>, tnilsson@cam.ac.uk (Tobias Nilsson) writes: > If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack! > Unsubscribe me from this list! (Wait, this is Usenet, never mind). Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. -- Mathieu Vasiliev Tape trading list upon request. SASE required for international mail.