37 lines
1.1 KiB
Go
37 lines
1.1 KiB
Go
// Copyright (c) 2015 The btcsuite developers
|
|
// Use of this source code is governed by an ISC
|
|
// license that can be found in the LICENSE file.
|
|
|
|
// This file implements range-based zeroing, which as of Go 1.5 is
|
|
// optimized using a Duff's device. See slice14.go for an implementation
|
|
// optimized for previous Go versions.
|
|
//
|
|
// +build !go1.3,!go1.4
|
|
|
|
package zero
|
|
|
|
import "math/big"
|
|
|
|
// Bytes sets all bytes in the passed slice to zero. This is used to
|
|
// explicitly clear private key material from memory.
|
|
//
|
|
// In general, prefer to use the fixed-sized zeroing functions (Bytea*)
|
|
// when zeroing bytes as they are much more efficient than the variable
|
|
// sized zeroing func Bytes.
|
|
func Bytes(b []byte) {
|
|
for i := range b {
|
|
b[i] = 0
|
|
}
|
|
}
|
|
|
|
// BigInt sets all bytes in the passed big int to zero and then sets the
|
|
// value to 0. This differs from simply setting the value in that it
|
|
// specifically clears the underlying bytes whereas simply setting the value
|
|
// does not. This is mostly useful to forcefully clear private keys.
|
|
func BigInt(x *big.Int) {
|
|
b := x.Bits()
|
|
for i := range b {
|
|
b[i] = 0
|
|
}
|
|
x.SetInt64(0)
|
|
}
|