Golang NewKeccak256 Examples

Example #1

File: dagger.go Project: Etherbeard/go-ethereum

func (dag *Dagger) Eval(N *big.Int) *big.Int {
	pow := ethutil.BigPow(2, 26)
	dag.xn = pow.Div(N, pow)

	sha := sha3.NewKeccak256()
	sha.Reset()
	ret := new(big.Int)

	for k := 0; k < 4; k++ {
		d := sha3.NewKeccak256()
		b := new(big.Int)

		d.Reset()
		d.Write(dag.hash.Bytes())
		d.Write(dag.xn.Bytes())
		d.Write(N.Bytes())
		d.Write(big.NewInt(int64(k)).Bytes())

		b.SetBytes(Sum(d))
		pk := (b.Uint64() & 0x1ffffff)

		sha.Write(dag.Node(9, pk).Bytes())
	}

	return ret.SetBytes(Sum(sha))
}

Example #2

File: dagger.go Project: Etherbeard/go-ethereum

func (dag *Dagger) Node(L uint64, i uint64) *big.Int {
	if L == i {
		return dag.hash
	}

	var m *big.Int
	if L == 9 {
		m = big.NewInt(16)
	} else {
		m = big.NewInt(3)
	}

	sha := sha3.NewKeccak256()
	sha.Reset()
	d := sha3.NewKeccak256()
	b := new(big.Int)
	ret := new(big.Int)

	for k := 0; k < int(m.Uint64()); k++ {
		d.Reset()
		d.Write(dag.hash.Bytes())
		d.Write(dag.xn.Bytes())
		d.Write(big.NewInt(int64(L)).Bytes())
		d.Write(big.NewInt(int64(i)).Bytes())
		d.Write(big.NewInt(int64(k)).Bytes())

		b.SetBytes(Sum(d))
		pk := b.Uint64() & ((1 << ((L - 1) * 3)) - 1)
		sha.Write(dag.Node(L-1, pk).Bytes())
	}

	ret.SetBytes(Sum(sha))

	return ret
}

Example #3

File: helpers.go Project: Etherbeard/ethutil-go

func Sha3Bin(data []byte) []byte {
	d := sha3.NewKeccak256()
	d.Reset()
	d.Write(data)

	return d.Sum(nil)
}

Example #4

File: dagger.go Project: josephyzhou/eth-go

func (pow *EasyPow) Verify(hash []byte, diff *big.Int, nonce []byte) bool {
	sha := sha3.NewKeccak256()

	d := append(hash, nonce...)
	sha.Write(d)

	v := ethutil.BigPow(2, 256)
	ret := new(big.Int).Div(v, diff)

	res := new(big.Int)
	res.SetBytes(sha.Sum(nil))

	return res.Cmp(ret) == -1
}