Re: [Cfrg] Fwd: I-D Action: draft-nir-cfrg-chacha20-poly1305-00.txt

[Yoav Nir <[e-mail]>]

On Jan 28, 2014, at 1:34 AM, Ilari Liusvaara <[e-mail]>
 wrote:

> On Mon, Jan 27, 2014 at 10:15:26PM +0000, Yoav Nir wrote:
> 
>> Filename        : draft-nir-cfrg-chacha20-poly1305-00.txt
> 
> 
> 
>>  Rounds 1-4 are part of the "column" round, while 5-8 are part of the
>>  "diagonal" round:
> 
> Should the first "Rounds" be "Quaterrounds" or something?

1, 2, 3, and 4 are quarter-rounds. Together they make up a round. In this case, a column round.

> 
>>  AEAD Construction for Poly1305:
>>  000  50 51 52 53 0c 00 00 00 00 00 00 00 0c 00 00 00|PQRS............
>>  016  00 00 00 00 d3 1a 8d 34 64 8e 60 db 7b 86 af bc|.......4d.`.{...
>>  032  53 ef 7e c2 a4 ad ed 51 29 6e 08 fe a9 e2 b5 a7|S.~....Q)n......
>>  048  36 ee 62 d6 3d be a4 5e 8c a9 67 12 82 fa fb 69|6.b.=..^..g....i
>>  064  da 92 72 8b 1a 71 de 0a 9e 06 0b 29 05 d6 a5 b6|..r..q.....)....
>>  080  7e cd 3b 36 92 dd bd 7f 2d 77 8b 8c 98 03 ae e3|~.;6...-w......
>>  096  28 09 1b 58 fa b3 24 e4 fa d6 75 94 55 85 80 8b|(..X..$...u.U...
>>  112  48 31 d7 bc 3f f4 de f0 8e 4b 7a 9d e5 76 d2 65|H1..?....Kz..v.e
>>  128  86 ce c6 4b 61 16 72 00 00 00 00 00 00 00      |...Ka.r.......
> 
> What are that stuff at the begnning (the first 20 bytes)? The
> 12 byte additional data + its length?

It is. The AAD is "50:51:52:53:0c:00:00:00:00:00:00:00". Now that you mention it, I see that I omitted to include the AAD in my example. Will fix in the next revision (coming soon)

Thanks

Yoav