From claurent@cam.ac.uk Sun Apr 17 03:33:34 1994 Path: ashpoly!cascade!transat!ukc!fennimore!cam!claurent From: claurent@cam.ac.uk (Callum Laurent) Newsgroups: comp.sys.m68k Subject: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994Apr17.033334.7711@cam.ac.uk> Date: Sun, 17 Apr 1994 03:33:34 GMT Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 10 Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board. 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'? -- Callum Laurent Tape trading list upon request. SASE required for international mail. From mrodriguez@earthlink.net Sun Apr 17 06:21:34 1994 Path: ashpoly!cascade!brgate!saturno!earthlink!mrodriguez From: mrodriguez@earthlink.net (Matthias Rodríguez) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994Apr17.062134.1758@earthlink.net> Date: Sun, 17 Apr 1994 06:21:34 GMT References: <1994Apr17.033334.7711@cam.ac.uk> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: NewsWatcher 2.0b24 Lines: 12 In article <1994Apr17.033334.7711@cam.ac.uk>, claurent@cam.ac.uk (Callum Laurent) writes: > Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board. > 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. Top-posters will be placed in my ~/.killfile without notice. -- Matthias Rodríguez *PLONK* filter active for trolls. Commodore Amiga 500 (1MB OCS) - NetBSD 1.0 From mfournier@rwth-aachen.de Mon Apr 18 07:43:34 1994 Path: ashpoly!cascade!transat!ukc!fennimore!rwth-aachen!mfournier From: mfournier@rwth-aachen.de (Mathieu Fournier) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994Apr18.074334.7554@rwth-aachen.de> Date: Mon, 18 Apr 1994 07:43:34 GMT References: <1994Apr17.033334.7711@cam.ac.uk> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Apr17.033334.7711@cam.ac.uk>, claurent@cam.ac.uk (Callum Laurent) 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. -- Mathieu Fournier *PLONK* filter active for trolls. 486DX2/66 (Linux 1.2.13) - NetBSD 1.0 From hgarcia@pacbell.net Mon Apr 18 11:21:34 1994 Path: ashpoly!cascade!brgate!saturno!pacbell!hgarcia From: hgarcia@pacbell.net (Heather García) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994Apr18.112134.7850@pacbell.net> Date: Mon, 18 Apr 1994 11:21:34 GMT References: <1994Apr17.033334.7711@cam.ac.uk> <1994Apr17.062134.1758@earthlink.net> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1994Apr17.062134.1758@earthlink.net>, mrodriguez@earthlink.net (Matthias Rodríguez) writes: > Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. > Top-posters will be placed in my ~/.killfile without notice. If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack! -- Heather García | hgarcia@pacbell.net PGP Key fingerprint: DA79 B5CE 44A5 19B0 "Keep the channels open."