1994-06-03 - Re: Faster way to deescrow Clipper won’t work

Header Data

From: sidney@taurus.apple.com (Sidney Markowitz)
To: cypherpunks@toad.com
Message Hash: dbc6928c7aa3fd6a62a60d6446a0672d95b85091ee6e425c3ca1654322584b33
Message ID: <9406031629.AA13941@federal-excess.apple.com>
Reply To: N/A
UTC Datetime: 1994-06-03 16:30:14 UTC
Raw Date: Fri, 3 Jun 94 09:30:14 PDT

Raw message

From: sidney@taurus.apple.com (Sidney Markowitz)
Date: Fri, 3 Jun 94 09:30:14 PDT
To: cypherpunks@toad.com
Subject: Re: Faster way to deescrow Clipper won't work
Message-ID: <9406031629.AA13941@federal-excess.apple.com>
MIME-Version: 1.0
Content-Type: text/plain

Perry answered most of my questions with the new information that the
checksum is a function of the IV and session key. That still leaves one big
one unanswered: Doesn't the Clipper chip at the other end of the message
have to compute and send a LEAF too? Otherwise there would be no way for
the wiretappers to identify it. And that LEAF will contain the proper
session key unless both ends are using the same hack.

Also, what does Clipperphone have that the Tessera board doesn't which
keeps this hack from working? Is enough known about the workings of the two
so that someone could build a computer-based telephone using Tessera that
would be compatible with Clipperphone yet use this hack?

 -- sidney <sidney@taurus.apple.com>