37 lines
960 B
Go
37 lines
960 B
Go
// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
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// Use of this source code is governed by an MIT license
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// that can be found in the LICENSE file.
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module cipher
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// NOTE: Implement other versions (joe-c)
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// xor_bytes xors the bytes in a and b. The destination should have enough
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// space, otherwise xor_bytes will panic. Returns the number of bytes xor'd.
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pub fn xor_bytes(dst mut []byte, a, b []byte) int {
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mut n := a.len
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if b.len < n {
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n = b.len
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}
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if n == 0 {
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return 0
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}
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safe_xor_bytes(mut dst, a, b, n)
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return n
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}
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// n needs to be smaller or equal than the length of a and b.
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pub fn safe_xor_bytes(dst mut []byte, a, b []byte, n int) {
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for i := 0; i < n; i++ {
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dst[i] = a[i] ^ b[i]
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}
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}
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// fast_xor_words XORs multiples of 4 or 8 bytes (depending on architecture.)
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// The slice arguments a and b are assumed to be of equal length.
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pub fn xor_words(dst mut []byte, a, b []byte) {
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safe_xor_bytes(mut dst, a, b, b.len)
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}
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