Signature Speed Up

[antonio-fr]

Slightly modify ECDSA lib, so that signature have a parity bit for yR.
This is as described in ECDSA-SEC1 v2.
Bitcoin signature are 2 times faster. No need to try and test anymore.

[ecdsa]

thanks. I will try to merge this as a child class, by looking at the diffs

[ecdsa]

it would be nice if you could clone the python-ecdsa repo and push your changes there.
that would make code review a lot easier

[antonio-fr]

With the lot of changes in python-ecdsa lib, I cannot succeed in doing like I wanted. I tried multiple times, but fork & roll-back I can't commit.

I finally made a unidiff from ecdsa lib in electrum 1.9.8 package :
http://pastebin.com/BwryNgC5

[ecdsa]

python-ecdsa might not be the best choice when it comes to adding optimizations.
maybe we should use pybitcointools instead.

[slush0]

@ecdsa This reminds me - would you like to use trezor-crypto if we make python binding for it? It is highly optimized and well tested C code, which would speed up Electrum by order of magnitude.

However I remember that you preferred to use pure python in Electrum. So just let me know if you're interested.

[ecdsa]

we can use a c library, if a pure python fallback exists.
this is what tlslite does

[ecdsa]

closing, out of scope