How to double the AES keysize in keepass?

Question

keepass is open source on github right? Is there any way to "append" its existing AES256, double the key size, make the program support AES512? What are ways to achieve that result

Thanks

Answer 1

AES does only supports keysizes of 128, 192 and 256 bits. See Wikipedia

Changing an AES implementation to use 512bit keys would require some experience in cryptography.

Considering that the best attacks on AES are only slightly better than brute-force (and are not real-world feasible) there is no reason to use larger keys. Bruteforcing 256 bits is not possible in the lifetime of the human race.

Answer 2

It should be possible to implement an AES-style encryption algorithm using 512 bits in theory. However, it is significantly more complicated than appending 2 AES256 keys onto each other. For more details check out this post and linked paper on the Cryptography Stack Exchange.

On Keepass in particular, the source code is available here. However, it appears to be implemented in c++, not python, so you may wish to change the tag on your question. I'm not familiar with the code base so I'm not sure which file you should start with.