1994-06-17 - Re: Prime magnitude and keys…a ?

Header Data

From: Jim choate <ravage@bga.com>
To: cdodhner@indirect.com
Message Hash: 8094bcd3140732ec37a2c759ba7ed08c9ae7c432ed90effaabc7d94b5b3922ed
Message ID: <199406171537.KAA01766@zoom.bga.com>
Reply To: <Pine.3.89.9406170844.A8295-0100000@id1.indirect.com>
UTC Datetime: 1994-06-17 15:37:31 UTC
Raw Date: Fri, 17 Jun 94 08:37:31 PDT

Raw message

From: Jim choate <ravage@bga.com>
Date: Fri, 17 Jun 94 08:37:31 PDT
To: cdodhner@indirect.com
Subject: Re: Prime magnitude and keys...a ?
In-Reply-To: <Pine.3.89.9406170844.A8295-0100000@id1.indirect.com>
Message-ID: <199406171537.KAA01766@zoom.bga.com>
MIME-Version: 1.0
Content-Type: text

> What do you mean by "greater or lesser than the actual key"? If you mean 
> number of bits you can do a simply file size comparison, if you mean 
> binary numerical value a simple c program _should_ be able to handle that 
> without any trouble I think.... although maybe you would need to include 
> some of those 'big number' routines I keep hearing about... and you would 
> have to strip off any header info before computing.
> Happy Hunting, -Chris.
What I am looking at is a way to do binary searches in the key space w/ a 
function that would look at a test key and the result of running RSA on 
it and then tell me the relative magnitude between the real key and the
test key. 

What this means is that I could take a cypher-text and attempt a de-crypt
w/ some conveniently large number and then go up or down from there 
till I find it. The advantage of this approach is that it allows one to
search the key-space w/o having to test each and every possibility. This
would significantly(!) reduce the time to crack...