Feature Request: Post-Quantum Cryptography support with ML-KEM

[SnarkSquatch]

Hi @diorwave

I'm interested in contributing a post-quantum security upgrade to cmd-chat. It currently uses SRP=AES128, which are vulnerable to attacks from quantum computers.

Proposed changes:
Replace SRP with ML-KEM (post-quantum key encapsulation)
Upgrade AES-128 to AES-256
This maintains the overall architecture and zero-knowledge properties

Benefits:
Future proofing against quantum threats
ML-KEM has minimal performance impact (roughly 10 to 50ms per connection)
Aligns with emerging cryptography standards (NIST post-quantum standardization)

Tradeoffs:
Adds dependency on liboqs-python
Key sizes increase slightly (roughly 1KB per connection)
Would require testing

Would you be open to a pull request with this change? I'm happy to implement it if you're interested.

[diorwave]

pls implement

[SnarkSquatch]

Will do. I'll have it sent your way this time next week.

[SnarkSquatch]

@diorwave

Following up:

I've upgraded aes128/fernet to aes256/aesgcm, removed fernet dependencies, and updated key derivation in client.py to produce 32byte (256bit) keys via HKDF. I avoided touching server side logic to keep your original intent. The server is just a blind relay.

I ran the client, sent a message, and it rendered and decrypted.

I commented out the fernet code in the files so you can see what was done. Let me know if you'd like me to remove them before merging. I wanted to do this first before getting to work on ML-KEM because it's the least intrusive upgrade. I'll hold and wait to hear from you before getting to work on the rest.

You can review the changes here: https://github.com/SnarkSquatch/cmd-chat