Commit Graph

4 Commits

Author SHA1 Message Date
Felix Lange
c6069a627c
crypto, crypto/secp256k1: add CompressPubkey (#15626)
This adds the inverse to DecompressPubkey and improves a few minor
details in crypto/secp256k1.
2017-12-15 10:40:09 +01:00
Felix Lange
5f7826270c all: unify big.Int zero checks, use common/math in more places (#3716)
* common/math: optimize PaddedBigBytes, use it more

name              old time/op    new time/op    delta
PaddedBigBytes-8    71.1ns ± 5%    46.1ns ± 1%  -35.15%  (p=0.000 n=20+19)

name              old alloc/op   new alloc/op   delta
PaddedBigBytes-8     48.0B ± 0%     32.0B ± 0%  -33.33%  (p=0.000 n=20+20)

* all: unify big.Int zero checks

Various checks were in use. This commit replaces them all with Int.Sign,
which is cheaper and less code.

eg templates:

    func before(x *big.Int) bool { return x.BitLen() == 0 }
    func after(x *big.Int) bool  { return x.Sign() == 0 }

    func before(x *big.Int) bool { return x.BitLen() > 0 }
    func after(x *big.Int) bool  { return x.Sign() != 0 }

    func before(x *big.Int) int { return x.Cmp(common.Big0) }
    func after(x *big.Int) int  { return x.Sign() }

* common/math, crypto/secp256k1: make ReadBits public in package math
2017-02-28 15:09:11 +01:00
Felix Lange
e0ceeab0d1 crypto/secp256k1: update to github.com/bitcoin-core/secp256k1 @ 9d560f9 (#3544)
- Use defined constants instead of hard-coding their integer value.
- Allocate secp256k1 structs on the C stack instead of converting []byte
- Remove dead code
2017-01-12 21:29:11 +01:00
Gustav Simonsson
c8ad64f33c crypto, crypto/ecies, crypto/secp256k1: libsecp256k1 scalar mult
thanks to Felix Lange (fjl) for help with design & impl
2015-11-30 13:43:32 +01:00