add some whitening to the IV as it goes down the path
This commit is contained in:
@ -1,4 +1,4 @@
|
||||
<code>$Id: tunnel.html,v 1.3 2005/01/12 14:22:40 jrandom Exp $</code>
|
||||
<code>$Id: tunnel.html,v 1.4 2005/01/12 19:57:36 jrandom Exp $</code>
|
||||
<pre>
|
||||
1) <a href="#tunnel.overview">Tunnel overview</a>
|
||||
2) <a href="#tunnel.operation">Tunnel operation</a>
|
||||
@ -248,9 +248,9 @@ for certain whether any of the checksum blocks have been tagged, as that would
|
||||
corrupt the verification block (V[7]).</p>
|
||||
|
||||
<p>The IV[0] is a random 16 byte value, and IV[i] is the first 16 bytes of
|
||||
H(D(IV[i-1], K[i-1])). We don't use the same IV along the path, as that would
|
||||
H(D(IV[i-1], K[i-1]) xor IV_WHITENER). We don't use the same IV along the path, as that would
|
||||
allow trivial collusion, and we use the hash of the decrypted value to propogate
|
||||
the IV so as to hamper key leakage.</p>
|
||||
the IV so as to hamper key leakage. IV_WHITENER is a fixed 16 byte value.</p>
|
||||
|
||||
<p>When the gateway wants to send the message, they export the right row for the
|
||||
peer who is the first hop (usually the peer1.recv row) and forward that entirely.</p>
|
||||
|
Reference in New Issue
Block a user