[47550] in Cypherpunks
Re: Hack Lotus?
daemon@ATHENA.MIT.EDU (hallam@w3.org)
Fri Jan 19 18:40:44 1996
To: cypherpunks@toad.com
Cc: hallam@w3.org
In-Reply-To: Your message of "Fri, 19 Jan 96 17:14:35 EST."
<199601192214.RAA28470@bb.hks.net>
Date: Fri, 19 Jan 96 18:15:31 -0500
From: hallam@w3.org
I've been thinking about how I would do the lotus hack. I certainly would not be
wanting to do a public key operation for the benefit of the government on every
message. How about the following:
During installation of program:
Select a random key ER, encrypt it under the govt. public key to give Eg(ER).
To start encrypting,
chose a random value R, encrypt under destination public key to give Ek(R)
set 40 bits of R to 0 to produce R'
Encrypt R' under ER to give E-ER(R')
Hash R, E-ER(R') and Eg(ER) with a one way function (MDMF like) to produce the
actual key.
Send across Ek(R), E-ER(R'), Eg(ER)
To decrypt the message one needs the information for the escrow authority.
Phill
