Function nettle_ocb_decrypt 

pub unsafe extern "C" fn nettle_ocb_decrypt(
    ctx: *mut ocb_ctx,
    key: *const ocb_key,
    encrypt_ctx: *const c_void,
    encrypt: nettle_cipher_func,
    decrypt_ctx: *const c_void,
    decrypt: nettle_cipher_func,
    length: usize,
    dst: *mut u8,
    src: *const u8,
)