Post-Quantum safeness

[1082008]

Current implementation uses curve25519 ECDH for key exchange and ed25519 for signatures. Although elliptic curve cryptography is not safe against attacks by quantum computers. Can secret handshake be rebased on New Hope for key exchange and SPHINCS for signatures?

[dominictarr]

I understand that basically SPHINCS is a hash based signature, but it can be used so many times that it seems permanent, and is otherwise drop in to asymmetric signatures (but much larger keys & signatures)

Bascially, if we had a post quantum key exchange with the same api as diffie helman, then yes. I only have time to skim the introduction to that paper currently, and it's unclear to me whether that has been developed (but I am sure someone is working on it). That paper talks about quantum-hardening TLS, but TLS has a variety of mechanisms to do key exchange, some of which involve DiffieHelman, but not all.

But if you can do a DH style key exchange, and this lattice based crypto sounds promising, then probably the answer is yes.