github.com/sberex/go-sberex@v1.8.2-0.20181113200658-ed96ac38f7d7/crypto/randentropy/rand_entropy.go (about) 1 // This file is part of the go-sberex library. The go-sberex library is 2 // free software: you can redistribute it and/or modify it under the terms 3 // of the GNU Lesser General Public License as published by the Free 4 // Software Foundation, either version 3 of the License, or (at your option) 5 // any later version. 6 // 7 // The go-sberex library is distributed in the hope that it will be useful, 8 // but WITHOUT ANY WARRANTY; without even the implied warranty of 9 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser 10 // General Public License <http://www.gnu.org/licenses/> for more details. 11 12 package randentropy 13 14 import ( 15 crand "crypto/rand" 16 "io" 17 ) 18 19 var Reader io.Reader = &randEntropy{} 20 21 type randEntropy struct { 22 } 23 24 func (*randEntropy) Read(bytes []byte) (n int, err error) { 25 readBytes := GetEntropyCSPRNG(len(bytes)) 26 copy(bytes, readBytes) 27 return len(bytes), nil 28 } 29 30 func GetEntropyCSPRNG(n int) []byte { 31 mainBuff := make([]byte, n) 32 _, err := io.ReadFull(crand.Reader, mainBuff) 33 if err != nil { 34 panic("reading from crypto/rand failed: " + err.Error()) 35 } 36 return mainBuff 37 }