54.4.9.3 Flags

AES_ISR.EOPAD rises as soon as the automatic padding phase is over, meaning that all the extra padding blocks have been processed. Reading AES_ISR clears this flag.

AES_ISR.PLENERR indicates an error in the frame configuration, meaning that the whole message length including padding does not respect the standard selected. AES_ISR.PLENERR rises at the end of the frame in case of wrong message length and is cleared reading AES_ ISR.

In IPSec/SSL standard message length including padding must be a multiple of the AES block size when CBC mode is used and multiple of 32-bit if CTR mode is used.