47 lines
1.7 KiB
Go
47 lines
1.7 KiB
Go
// Copyright (c) 2015 The btcsuite developers
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//
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// Permission to use, copy, modify, and distribute this software for any
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// purpose with or without fee is hereby granted, provided that the above
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// copyright notice and this permission notice appear in all copies.
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//
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// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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// This file implements range-based zeroing, which as of Go 1.5 is
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// optimized using a Duff's device. See slice14.go for an implementation
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// optimized for previous Go versions.
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//
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// +build !go1.3,!go1.4
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package zero
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import "math/big"
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// Bytes sets all bytes in the passed slice to zero. This is used to
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// explicitly clear private key material from memory.
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//
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// In general, prefer to use the fixed-sized zeroing functions (Bytea*)
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// when zeroing bytes as they are much more efficient than the variable
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// sized zeroing func Bytes.
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func Bytes(b []byte) {
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for i := range b {
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b[i] = 0
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}
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}
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// BigInt sets all bytes in the passed big int to zero and then sets the
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// value to 0. This differs from simply setting the value in that it
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// specifically clears the underlying bytes whereas simply setting the value
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// does not. This is mostly useful to forcefully clear private keys.
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func BigInt(x *big.Int) {
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b := x.Bits()
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for i := range b {
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b[i] = 0
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}
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x.SetInt64(0)
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}
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