1994-06-03 - Re: Black Eye for NSA, NIST, and Denning

Header Data

From: “Perry E. Metzger” <perry@imsi.com>
To: cypherpunks@toad.com
Message Hash: 2bf7b8447d73c96d9732f200c64a210184a07cc3c1c3fdb19a16c3417ab23481
Message ID: <9406031142.AA03737@snark.imsi.com>
Reply To: <9406022244.AA18607@io.lrcs.loral.com>
UTC Datetime: 1994-06-03 11:43:42 UTC
Raw Date: Fri, 3 Jun 94 04:43:42 PDT

Raw message

From: "Perry E. Metzger" <perry@imsi.com>
Date: Fri, 3 Jun 94 04:43:42 PDT
To: cypherpunks@toad.com
Subject: Re: Black Eye for NSA, NIST, and Denning
In-Reply-To: <9406022244.AA18607@io.lrcs.loral.com>
Message-ID: <9406031142.AA03737@snark.imsi.com>
MIME-Version: 1.0
Content-Type: text/plain

David Koontz says:
> Gee, now that mab@research.att.com (Matt Blaze), knows where to find
> the checksum,

Actually, he doesn't. He only knows how long it is, and what went into
generating it. That is enough.

> and by extension the unit id (Which shows up on labels
> in photos on the literature from Mykotronx) - providing a known plaintext,
> maybe someone will start working on the family key?

Skipjack is presumably immune to such attacks except by brute force. I
suspect that short of starting to reverse engineer the chip little
enough is known to provide information on the plaintext sufficient to
even know when you have cracked it. The encryption mode for the LEAF
is said to be unusual. All these things bode poorly for such a crack.