Does a setup_receiver and AeadCtx::open in one shot. That is, it does a key decapsulation
for the specified recipient and decrypts the provided plaintext in place. See
setup::setup_reciever and AeadCtx::open for more detail.
Does a setup_sender and AeadCtx::seal in one shot. That is, it does a key encapsulation to
the specified recipient and encrypts the provided plaintext in place. See setup::setup_sender
and AeadCtx::seal for more detail.