github.com/aquanetwork/aquachain@v1.7.8/crypto/randentropy/rand_entropy.go (about)

     1  // Copyright 2015 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package randentropy
    18  
    19  import (
    20  	crand "crypto/rand"
    21  	"io"
    22  )
    23  
    24  var Reader io.Reader = &randEntropy{}
    25  
    26  type randEntropy struct {
    27  }
    28  
    29  func (*randEntropy) Read(bytes []byte) (n int, err error) {
    30  	readBytes := GetEntropyCSPRNG(len(bytes))
    31  	copy(bytes, readBytes)
    32  	return len(bytes), nil
    33  }
    34  
    35  func GetEntropyCSPRNG(n int) []byte {
    36  	mainBuff := make([]byte, n)
    37  	_, err := io.ReadFull(crand.Reader, mainBuff)
    38  	if err != nil {
    39  		panic("reading from crypto/rand failed: " + err.Error())
    40  	}
    41  	return mainBuff
    42  }