Feature: Support Mode GCM in AES

[cs-shadowbq]

AES GCM mode

When using symmetric encryption, you should be using authenticated encryption, such as AES-GCM (Galois/Counter Mode), rather than unauthenticated encryption, such as AES-CBC (Cipher Block Chaining). AES-CBC is not authenticated encryption, so it is vulnerable to the various chosen-ciphertext attacks.

As of v1.3, TLS no longer supports AES-CBC. GCM includes an in-built integrity check.

an example: https://github.com/adrian154/blog/blob/main/generated-site/resources/tls/decrypt.js