From tsouza@ox.ac.uk Wed May 22 04:39:17 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!tsouza From: tsouza@ox.ac.uk (Takeshi Souza) Newsgroups: comp.sys.m68k Subject: Discussion: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996May22.043917.3311@ox.ac.uk> Date: Wed, 22 May 1996 04:39:17 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: Netscape 1.1N Lines: 11 Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. This indicates socket U14 held a cryptographic S-box lookup table for decrypting the Stardust keystream. Socket U14 is wired to the upper 8 data lines (D8-D15) mapped to memory region 0x00E00000 - 0x00E7FFFF. Did Marcus take the decryption EPROM with him when he left the lab? -- Takeshi Souza Practical Peripherals 14.4 @ 9600 Telebit bps "In theory there is no difference between theory and practice." From mchoi@delphi.com Thu May 23 10:05:17 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!delphi!mchoi From: mchoi@delphi.com (Mike Choi) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996May23.100517.1083@delphi.com> Date: Thu, 23 May 1996 10:05:17 GMT References: <1996May22.043917.3311@ox.ac.uk> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1996May22.043917.3311@ox.ac.uk>, tsouza@ox.ac.uk (Takeshi Souza) 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. -- Mike Choi -- Delphi Internet Services "Measuring a record you own is listening, not piracy." From ykarlsson@pipeline.com Thu May 23 15:26:17 1996 Path: ashpoly!cascade!mxgate!coyoacan!pipeline!ykarlsson From: ykarlsson@pipeline.com (Yuki Karlsson) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996May23.152617.8352@pipeline.com> Date: Thu, 23 May 1996 15:26:17 GMT References: <1996May22.043917.3311@ox.ac.uk> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1996May22.043917.3311@ox.ac.uk>, tsouza@ox.ac.uk (Takeshi Souza) 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. -- Yuki Karlsson Tape trading list upon request. SASE required for international mail. From msuzuki@unam.mx Fri May 24 11:13:17 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!unam!msuzuki From: msuzuki@unam.mx (Matthias Suzuki) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996May24.111317.8000@unam.mx> Date: Fri, 24 May 1996 11:13:17 GMT References: <1996May22.043917.3311@ox.ac.uk> <1996May23.152617.8352@pipeline.com> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996May23.152617.8352@pipeline.com>, ykarlsson@pipeline.com (Yuki Karlsson) 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! -- Matthias Suzuki Practical Peripherals 14.4 @ 28,800 bps "Tape doesn't lie at 02:14. Ears do." From ebrennan@uni-hamburg.de Sun May 26 05:06:17 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!uni-hamburg!ebrennan From: ebrennan@uni-hamburg.de (Élodie Brennan) Newsgroups: comp.sys.m68k Subject: Re: Discussion: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1996May26.050617.8547@uni-hamburg.de> Date: Sun, 26 May 1996 05:06:17 GMT References: <1996May22.043917.3311@ox.ac.uk> <1996May23.152617.8352@pipeline.com> <1996May24.111317.8000@unam.mx> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1996May24.111317.8000@unam.mx>, msuzuki@unam.mx (Matthias Suzuki) writes: > If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack! Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. -- Élodie Brennan Tape trading list upon request. SASE required for international mail.