36 lines
		
	
	
		
			692 B
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			36 lines
		
	
	
		
			692 B
		
	
	
	
		
			Go
		
	
	
	
	
	
| package randentropy
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| 
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| import (
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| 	crand "crypto/rand"
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| 	"github.com/ethereum/go-ethereum/crypto/sha3"
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| 	"io"
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| )
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| 
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| var Reader io.Reader = &randEntropy{}
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| 
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| type randEntropy struct {
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| }
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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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| 
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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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| 
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| 	return d.Sum(nil)
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| }
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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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