16 lines
611 B
Rust
16 lines
611 B
Rust
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/// CompressHash takes an arbitrary long sequence of bytes (usually a hash
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/// digest), and returns a sequence of bytes of length output_size.
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/// It's calculated by rotating through the bytes in the output buffer (zero-
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/// initialized), and XOR'ing with each byte of the passed input.
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/// It consumes 1 byte at a time, and XOR's it with the current value in the
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/// output buffer.
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pub fn compress_hash(input: &[u8], output_size: usize) -> Vec<u8> {
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let mut output: Vec<u8> = vec![0; output_size];
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for (ii, ch) in input.iter().enumerate() {
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output[ii % output_size] ^= ch;
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}
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output
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}
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