Function encrypt

pub fn encrypt<C, T, R, W>(
    block_size: usize,
    checksum: C,
    rng: &mut T,
    src: &mut R,
    dst: &mut W,
) -> Result<(u64, u64)>
where
    C: Checksum,
    T: IntRng,
    R: Read,
    W: Write,