Re: [quicwg/base-drafts] Keep PN out of AEAD (#1578)

MikkelFJ <notifications@github.com> Tue, 17 July 2018 16:54 UTC

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Subject: Re: [quicwg/base-drafts] Keep PN out of AEAD (#1578)
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So not sure why github posted that before I was done, but

it means that the packet number can stay as it is but not affect the tag. This means the decryption and verification can be done by copying just the encrypted PN to a small side buffer to derive the IV and then verify or decrypt without having to modify the incoming payload.

This can simplify hardware and multi-processor buffer sharing.

It also simplifies decrypting the PN because it can be decoded as if it were full length and never bother potential for overwriting data that is not part of the PN - since it happens in a separate buffer as discussed in https://github.com/quicwg/base-drafts/issues/1575

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