From mhughes@ox.ac.uk Thu Apr 27 22:27:26 1995 Path: ashpoly!cascade!brgate!saturno!ox!mhughes From: mhughes@ox.ac.uk (Mikhail Hughes) Newsgroups: comp.sys.m68k Subject: Observation: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Apr27.222726.2428@ox.ac.uk> Date: Thu, 27 Apr 1995 22:27:26 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: Netscape 1.1N Lines: 11 Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board. This indicates socket U14 held a cryptographic S-box lookup table for decrypting the Stardust keystream. 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'? -- Mikhail Hughes | mhughes@ox.ac.uk PGP Key fingerprint: 4C0D 2AC9 DE2B 578D "Keep the channels open." From vnilsson@pacbell.net Fri Apr 28 03:56:26 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!pacbell!vnilsson From: vnilsson@pacbell.net (Valeria Nilsson) Newsgroups: comp.sys.m68k Subject: Re: Observation: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Apr28.035626.7323@pacbell.net> Date: Fri, 28 Apr 1995 03:56:26 GMT References: <1995Apr27.222726.2428@ox.ac.uk> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Apr27.222726.2428@ox.ac.uk>, mhughes@ox.ac.uk (Mikhail Hughes) 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. -- Valeria Nilsson Opinions expressed are solely my own and not those of Pacific Bell Internet Services. ------------------------------------------------------------ From ckang@illinois.edu Sat Apr 29 22:25:26 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!illinois!ckang From: ckang@illinois.edu (Callum Kang) Newsgroups: comp.sys.m68k Subject: Re: Observation: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Apr29.222526.7363@illinois.edu> Date: Sat, 29 Apr 1995 22:25:26 GMT References: <1995Apr27.222726.2428@ox.ac.uk> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Apr27.222726.2428@ox.ac.uk>, mhughes@ox.ac.uk (Mikhail Hughes) writes: > Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board. If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack! Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Callum Kang *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0 From fnovak@pacbell.net Sun Apr 30 06:03:26 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!pacbell!fnovak From: fnovak@pacbell.net (Freya Novak) Newsgroups: comp.sys.m68k Subject: Re: Observation: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Apr30.060326.4359@pacbell.net> Date: Sun, 30 Apr 1995 06:03:26 GMT References: <1995Apr27.222726.2428@ox.ac.uk> <1995Apr28.035626.7323@pacbell.net> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Apr28.035626.7323@pacbell.net>, vnilsson@pacbell.net (Valeria Nilsson) 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. -- Freya Novak Opinions expressed are solely my own and not those of Pacific Bell Internet Services. ------------------------------------------------------------