AEAD modes such as GCM authenticate optional associated data (AAD) and
produce an authentication tag, which the block-cipher encrypt/decrypt
interface cannot express. Add qcrypto_cipher_setaad() and
qcrypto_cipher_gettag() plus the matching backend driver hooks. The
generic front-end reports an error when the selected mode's driver does
not implement them, so calling them on a non-AEAD mode fails cleanly.
Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Kane Chen <kane_chen@aspeedtech.com>
Link: https://lore.kernel.org/qemu-devel/20260811060115.1849266-9-jamin_lin@aspeedtech.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>