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Re: Introducing TGP...
From: "Thor (Hammer of God)" <Thor () hammerofgod com>
Date: Tue, 15 Jun 2010 15:26:41 +0000

The SHA256 hashing of the private key may not result in authenticity
assurances on the key (if I'm reading it correctly). I believe that's
an Athenticate-then-Encrypt scheme, and the details of the
interactions in AtE can be tricky.

I had an opportunity to sleep on this, so here's my two cents. If I read the docs
correctly, this construction is:

ENC( HASH(m) || m )

No, that's not what I'm doing.  As I said in my message yesterday, I'm simply using the hash of the encrypted private 
key and the hash of the public key to see if the keys were tampered with while at rest.  
When loading the private key fob, a passphrase is required.  Before I prompt for the passphrase, I rehash the encrypted 
private key as stored, and compare that to the stored hash of the same.  If they are different, I flag an error.

I'll dive into your references though and see if any of it applies.  Thanks.


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