simultaneous symmetric and public key encryption ?

Per Tunedal pt@radvis.nu
Thu Dec 19 16:34:01 2002


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At 09:44 2002-12-19 -0500, you wrote:
 >On Thu, Dec 19, 2002 at 12:32:21PM +0100, Per Tunedal wrote:

 >> 2. Mallory now have the plaintext and the message encrypted with some
 >> secret keys.
 >
 >Yes.
 >
 >> 3. Mallary attacks the public key encryption and get the secret keys.
 >
 >No.  You can't get the secret key this way.  The most Mallory can get
 >is the plaintext.
 >
 >David

I supposed it would be some help to Mallory to possess the plaintext when 
attacking the encrypted text. Cf the Rosette stone used for "deciphering" 
the hieroglyphs ...

3a. Mallory gets the symmetric message key by attacking the message with 
some help from the plain text.

3b. Mallory attacks the encrypted session key with some help from the plain 
session key.

3c. Mallory gets the secret key used for encrypting the session key.

Per Tunedal

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