I've been struggling up the learning curve of encrypting some arbitrary data for sending for example over a LoRa connection.
In case there's anybody else in a similar situation I've written a simple demo program that runs under esp_idf on a esp32 module.
It creates necessary data structures and data and then encrypts to a buffer using AES_CBC and then decrypts it back to the beginning.
It can be found at: https://gitlab.com/nottledim/demo_esp_aes
If there's anything not right right let me know. Thanks