From dramirez@illinois.edu Thu Mar 17 17:59:15 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!illinois!dramirez From: dramirez@illinois.edu (Dong-hyun Ramírez) Newsgroups: comp.sys.m68k Subject: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994Mar17.175915.5992@illinois.edu> Date: Thu, 17 Mar 1994 17:59:15 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 11 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. 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? -- === Dong-hyun Ramírez === Dept of Electrical Engineering, University of Illinois Urbana-Champaign "Extraordinary claims require extraordinary spectra." From kpopov@berkeley.edu Sat Mar 19 04:49:15 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!kpopov From: kpopov@berkeley.edu (Kirsty Popov) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994Mar19.044915.9279@berkeley.edu> Date: Sat, 19 Mar 1994 04:49:15 GMT References: <1994Mar17.175915.5992@illinois.edu> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1994Mar17.175915.5992@illinois.edu>, dramirez@illinois.edu (Dong-hyun Ramírez) 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. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Kirsty Popov Hayes Optima 288 @ 14,400 bps "5 sigma is a discovery. 7 is a question." From krobertson@berkeley.edu Sat Mar 19 13:49:15 1994 Path: ashpoly!cascade!mxgate!coyoacan!berkeley!krobertson From: krobertson@berkeley.edu (Katrin Robertson) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1994Mar19.134915.1321@berkeley.edu> Date: Sat, 19 Mar 1994 13:49:15 GMT References: <1994Mar17.175915.5992@illinois.edu> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1994Mar17.175915.5992@illinois.edu>, dramirez@illinois.edu (Dong-hyun Ramírez) 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! Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Katrin Robertson -- UC Berkeley Department of EECS "Marcus is not one man."