34 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			V
		
	
	
			
		
		
	
	
			34 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			V
		
	
	
// Copyright (c) 2019-2021 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(mut dst []byte, a []byte, 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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// safe_xor_bytes XORs the bytes in `a` and `b` into `dst` it does so `n` times.
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// Please note: `n` needs to be smaller or equal than the length of `a` and `b`.
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pub fn safe_xor_bytes(mut dst []byte, a []byte, b []byte, n int) {
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	for i in 0 .. n {
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		dst[i] = a[i] ^ b[i]
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	}
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}
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// 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(mut dst []byte, a []byte, b []byte) {
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	safe_xor_bytes(mut dst, a, b, b.len)
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}
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