[Haskell-cafe] Re: Crypto-API is stabilizing

[Thomas DuBuisson]

On Thu, Sep 2, 2010 at 3:07 PM, Sebastian Fischer
<sebf at informatik.uni-kiel.de> wrote:
>>  data Key = Key {
>>               encrypt   :: B.ByteString -> B.ByteString,
>>               decrypt   :: B.ByteString -> B.ByteString,
>>               keyLength :: BitLength,
>>               serialize :: B.ByteString}
>>
>>  rsa :: RandomGen g => BitLength -> g -> ((Key,Key), g)

One reason against this is simply that all the other constructs
(block/stream cipher, hashes) are classes, it would be odd for there
to be a single exception.  A better reason is the data structure has
no way to implement generateKeyPair.

> Why not use
>
>    generateKeypair :: MonadRandom m => BitLength -> m (Maybe (p,p))

Because MonadRandom dictates mtl, and is heavier weight than a single
class.  I was hoping to keep this agnostic (mtl is only required for
testing or benchmarks in crypto-api).  If MR the more agreeable path
then I'll do it, though this means I use the unholy "fail" function.
Even if that's the case (and more people weighing in would help) I
still want to include Data.Crypto.Random and welcome comments.

Cheers,
Thomas