Function xor_keystream 

pub fn xor_keystream(
    data: &[u8],
    keystream: &[u8],
    output: &mut [u8],
) -> SimdResult<()>

Parallel XOR with key stream for encryption/decryption

Applies XOR operation between data and a repeating key stream. Optimized for stream cipher operations.

Arguments

• data - Input data
• keystream - Key stream to XOR with (will be repeated if shorter than data)
• output - Output buffer (must be same length as data)

Errors

Returns error if output buffer length doesn’t match data length.