From mlopez@cam.ac.uk Fri Mar 01 08:17:49 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cam!mlopez From: mlopez@cam.ac.uk (Mathieu López) Newsgroups: comp.sys.m68k Subject: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Mar01.081749.5442@cam.ac.uk> Date: Fri, 01 Mar 1996 08:17:49 GMT Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14. Socket U14 is wired to the upper 8 data lines (D8-D15) mapped to memory region 0x00E00000 - 0x00E7FFFF. Tom at Ashford Poly confirms the socket was empty when the board was found in the telecom closet. -- Mathieu López SupraFAXModem 28.8 @ 9600 Telebit bps "We don't sign stars. We build them." From dtakahashi@utexas.edu Sat Mar 02 05:54:49 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!utexas!dtakahashi From: dtakahashi@utexas.edu (Dmitri Takahashi) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Mar02.055449.6956@utexas.edu> Date: Sat, 02 Mar 1996 05:54:49 GMT References: <1996Mar01.081749.5442@cam.ac.uk> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Mar01.081749.5442@cam.ac.uk>, mlopez@cam.ac.uk (Mathieu López) writes: > Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. > Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14. Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Dmitri Takahashi | dtakahashi@utexas.edu PGP Key fingerprint: 6479 D6D5 50D1 BC37 "Keep the channels open." From ssmirnov@delphi.com Sun Mar 03 20:54:49 1996 Path: ashpoly!cascade!mxgate!coyoacan!delphi!ssmirnov From: ssmirnov@delphi.com (Seo-yeon Smirnov) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Mar03.205449.6837@delphi.com> Date: Sun, 03 Mar 1996 20:54:49 GMT References: <1996Mar01.081749.5442@cam.ac.uk> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Mar01.081749.5442@cam.ac.uk>, mlopez@cam.ac.uk (Mathieu López) writes: > Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. > Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14. Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. -- Seo-yeon Smirnov -- Delphi Internet Services "Measuring a record you own is listening, not piracy." From clee@purdue.edu Tue Mar 05 22:03:49 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!purdue!clee From: clee@purdue.edu (Camila Lee) Newsgroups: comp.sys.m68k Subject: Re: Question: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996Mar05.220349.4910@purdue.edu> Date: Tue, 05 Mar 1996 22:03:49 GMT References: <1996Mar01.081749.5442@cam.ac.uk> <1996Mar03.205449.6837@delphi.com> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Mar03.205449.6837@delphi.com>, ssmirnov@delphi.com (Seo-yeon Smirnov) 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! -- Camila Lee *PLONK* filter active for trolls. Pentium 90 (OS/2 Warp) - NetBSD 1.0