DroidFS/app/libgocryptfs/gocryptfs_internal/cryptocore/nonce.go

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2020-07-17 16:35:39 +02:00
package cryptocore
import (
"crypto/rand"
"encoding/binary"
"log"
)
// RandBytes gets "n" random bytes from /dev/urandom or panics
func RandBytes(n int) []byte {
b := make([]byte, n)
_, err := rand.Read(b)
if err != nil {
log.Panic("Failed to read random bytes: " + err.Error())
}
return b
}
// RandUint64 returns a secure random uint64
func RandUint64() uint64 {
b := RandBytes(8)
return binary.BigEndian.Uint64(b)
}
type nonceGenerator struct {
nonceLen int // bytes
}
// Get a random "nonceLen"-byte nonce
func (n *nonceGenerator) Get() []byte {
return randPrefetcher.read(n.nonceLen)
}