Question

Alright so my question isn’t as professional as it can be. Basically I want to know, do you think it’s secure enough to encrypt messages with AES and a custom (but static) key?

I want them to be decryptable with that same key but at the same time I don’t want anyone who doesn’t know the key to get access to them.

I’ve read that AES is the only government approved encryption method, not sure if its true or not but either way, does not say much.

Answer 1

AES is a secure block cipher algorithm (this is the current opinion of the cryptographic scene), if it is used correctly.

This means, that you should use a secure mode of operation – not ECB mode, and a random initialization vector for each message (this can be sent together with the message).

Of course, being a symmetric cipher, this means that you need to have a secret (and authentic, I guess) way to negotiate the key beforehand.

This is not a good idea if you want to embed the key in a software you are deploying to computers you don’t control – use a hybrid scheme with a public-key algorithm in this case, as mentioned by Michael.