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