53 lines
1.5 KiB
Go
53 lines
1.5 KiB
Go
// Copyright 2015 The go-ethereum Authors
|
|
// This file is part of the go-ethereum library.
|
|
//
|
|
// The go-ethereum library is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// The go-ethereum library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public License
|
|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
package randentropy
|
|
|
|
import (
|
|
crand "crypto/rand"
|
|
"io"
|
|
|
|
"github.com/ethereum/go-ethereum/crypto/sha3"
|
|
)
|
|
|
|
var Reader io.Reader = &randEntropy{}
|
|
|
|
type randEntropy struct {
|
|
}
|
|
|
|
func (*randEntropy) Read(bytes []byte) (n int, err error) {
|
|
readBytes := GetEntropyCSPRNG(len(bytes))
|
|
copy(bytes, readBytes)
|
|
return len(bytes), nil
|
|
}
|
|
|
|
// TODO: copied from crypto.go , move to sha3 package?
|
|
func Sha3(data []byte) []byte {
|
|
d := sha3.NewKeccak256()
|
|
d.Write(data)
|
|
|
|
return d.Sum(nil)
|
|
}
|
|
|
|
func GetEntropyCSPRNG(n int) []byte {
|
|
mainBuff := make([]byte, n)
|
|
_, err := io.ReadFull(crand.Reader, mainBuff)
|
|
if err != nil {
|
|
panic("reading from crypto/rand failed: " + err.Error())
|
|
}
|
|
return mainBuff
|
|
}
|