Subject: [Hipsec] BaseHIP Issue #42

From: [email-masked] (Ahrenholz, Jeffrey M)
Date: Thu Oct 7 11:20:01 2004

Petri,

> The key exchange described on page 12 of the base draft was a bit=20
> unclear. So, a new proposal:

This new text is much clearer.
I have a few suggested minor edits below.

-Jeff

<snip+edit>
     The second packet, R1, starts the actual exchange.  It contains a
     puzzle, that is, a cryptographic challenge that the Initiator must
     solve before continuing the exchange. In addition, it contains
     the initial Diffie-Hellman parameters and a signature, covering
     part of the message. Some fields are left outside the
     signature to support pre-created R1s.

     In the I2 packet, the Initiator must display the solution to the
received
     puzzle.  Without a correct solution, the I2 message is discarded.
The
     I2 also contains a Diffie-Hellman parameter that carries needed
     information for the Responder. The packet is signed by the sender.
=20
<snip+edit>
     In R1, the signature covers the packet, after setting the initiator
     HIT, header checksum, and the PUZZLE parameter's Opaque and Random
#I
     fields temporarily to zero, and excluding any TLVs that follow the
     signature.
=20
     In I2, the signature covers the whole packet, excluding=20
     any TLVs that follow the signature.
=20
     In R2, the signature and the HMAC cover the whole envelope.
=20
     In this section we cover the overall design of the base exchange.
     The details are the subject of the rest of this memo.