[tor-dev] RFC: AEZ for relay cryptography, v2

[Tim Wilson-Brown - teor]

> On 30 Nov 2015, at 09:13, Nick Mathewson <nickm at torproject.org> wrote:
> ...
> 2.2. New relay cell payload
> ...
>   When encrypting a cell for a hop that was created using one of these
>   circuits, clients and relays encrypt them using the AEZ algorithm
>   with the following parameters:
> 
>       Let Chain denote chain_val_forward if this is a forward cell
>          or chain_forward_backward otherwise.

chain_val_backward?

> ...
> 
> 3.3. Why _not_ AEZ?
> 
>   ...
> 
>   THIRD, it's really horrible to try to do it in hardware.

This may be considered an advantage against an adversary with the resources to employ custom hardware to attempt to break AEZ-based encryption.

> ...
> 
> ...
> 4.3. A forward-secure variant.

How is this different to what you've specified in the main body of the proposal?

> 
>   We might want the property that after every cell, we can forget
>   some secret that would enable us to decrypt that cell if we saw
>   it again.
> 
>   …

Tim

Tim Wilson-Brown (teor)

teor2345 at gmail dot com
PGP 968F094B

teor at blah dot im
OTR CAD08081 9755866D 89E2A06F E3558B7F B5A9D14F

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.torproject.org/pipermail/tor-dev/attachments/20151130/57d3d18d/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 842 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <http://lists.torproject.org/pipermail/tor-dev/attachments/20151130/57d3d18d/attachment-0001.sig>