From anovak@clari.net Wed Jan 24 21:49:53 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!clari!anovak From: anovak@clari.net (Astrid Novak) Newsgroups: comp.sys.m68k Subject: [SPECULATION] Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Jan24.214953.5754@clari.net> Date: Wed, 24 Jan 1996 21:49:53 GMT Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board. Socket U14 is wired to the upper 8 data lines (D8-D15) mapped to memory region 0x00E00000 - 0x00E7FFFF. 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'? -- Astrid Novak "The carrier frequency does not drift by accident." Sun SparcStation 20 / Linux 1.2.13 From fsouza@cmu.edu Fri Jan 26 00:22:53 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!cmu!fsouza From: fsouza@cmu.edu (Fiona Souza) Newsgroups: comp.sys.m68k Subject: Re: [SPECULATION] Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Jan26.002253.2385@cmu.edu> Date: Fri, 26 Jan 1996 00:22:53 GMT References: <1996Jan24.214953.5754@clari.net> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Jan24.214953.5754@clari.net>, anovak@clari.net (Astrid Novak) 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. -- Fiona Souza US Robotics Courier V.34 @ ISDN 64k bps "Measuring a record you own is listening, not piracy."