From trobertson@utexas.edu Sun Jul 14 04:35:50 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!utexas!trobertson From: trobertson@utexas.edu (Tobias Robertson) Newsgroups: comp.sys.m68k Subject: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Jul14.043550.9195@utexas.edu> Date: Sun, 14 Jul 1996 04:35:50 GMT Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu 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. This indicates socket U14 held a cryptographic S-box lookup table for decrypting the Stardust keystream. Did Marcus take the decryption EPROM with him when he left the lab? -- Tobias Robertson Opinions expressed are solely my own and not those of University of Texas at Austin. ------------------------------------------------------------ From dkang@earthlink.net Tue Jul 16 03:58:50 1996 Path: ashpoly!cascade!brgate!saturno!earthlink!dkang From: dkang@earthlink.net (Dave Kang) Newsgroups: comp.sys.m68k Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Jul16.035850.2899@earthlink.net> Date: Tue, 16 Jul 1996 03:58:50 GMT References: <1996Jul14.043550.9195@utexas.edu> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1996Jul14.043550.9195@utexas.edu>, trobertson@utexas.edu (Tobias Robertson) 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! -- Dave Kang Practical Peripherals 14.4 @ 9600 Telebit bps "Marcus is not one man." From rwatanabe@pipeline.com Thu Jul 18 05:34:50 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!pipeline!rwatanabe From: rwatanabe@pipeline.com (Raj Watanabe) Newsgroups: comp.sys.m68k Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Jul18.053450.2129@pipeline.com> Date: Thu, 18 Jul 1996 05:34:50 GMT References: <1996Jul14.043550.9195@utexas.edu> <1996Jul16.035850.2899@earthlink.net> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Jul16.035850.2899@earthlink.net>, dkang@earthlink.net (Dave Kang) writes: > Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack! -- Raj Watanabe *PLONK* filter active for trolls. Commodore Amiga 500 (1MB OCS) - NetBSD 1.0