From khughes@stanford.edu Wed May 04 05:31:52 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!stanford!khughes From: khughes@stanford.edu (Katrin Hughes) Newsgroups: comp.sys.m68k Subject: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994May04.053152.7538@stanford.edu> Date: Wed, 04 May 1994 05:31:52 GMT Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: NewsWatcher 2.0b24 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. This indicates socket U14 held a cryptographic S-box lookup table for decrypting the Stardust keystream. Does anyone have a 27C256 EPROM marked 'MH-U14' or 'ORION-CRYPTO'? -- Katrin Hughes "Hold for relay." Commodore Amiga 500 (1MB OCS) / SunOS 4.1.4 From mkang@ox.ac.uk Thu May 05 18:45:52 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!mkang From: mkang@ox.ac.uk (Matthias Kang) Newsgroups: comp.sys.m68k Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994May05.184552.5249@ox.ac.uk> Date: Thu, 05 May 1994 18:45:52 GMT References: <1994May04.053152.7538@stanford.edu> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1994May04.053152.7538@stanford.edu>, khughes@stanford.edu (Katrin Hughes) writes: > Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Matthias Kang "Hardware is temporary. The signal survives." Commodore Amiga 500 (1MB OCS) / System 7.5.1 From ksantos@cern.ch Sat May 07 22:08:52 1994 Path: ashpoly!cascade!brgate!saturno!cern!ksantos From: ksantos@cern.ch (Karen Santos) Newsgroups: comp.sys.m68k Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994May07.220852.2715@cern.ch> Date: Sat, 07 May 1994 22:08:52 GMT References: <1994May04.053152.7538@stanford.edu> <1994May05.184552.5249@ox.ac.uk> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994May05.184552.5249@ox.ac.uk>, mkang@ox.ac.uk (Matthias Kang) writes: > Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. -- Karen Santos "Tape doesn't lie at 02:14. Ears do." Atari TT030 / System 7.5.1