Im trying to learn more about cryptography and ran into a post, Is AES-128 quantum safe?, which asks if AES-128 is safe. From the articles and replies it seems that AES-128 (symmetric key) is safe even with the advent of quantum computers (for now). However, it seems that asymmetric keys are not safe?
So, assuming you have a TLS 1.3 (which uses symmetric AND asymmetric keys) would quantum computers be able to decrypt the traffic sent using a cypher like
TLS_AES_128_GCM_SHA256? Is decrypting the Diffie-Hellman (asymmetric key) enough to see the plaintext of something or would you still need to decrypt the AES-128 as well?
Do you need to decrypt both the symmetric and asymmetric key in a
TLS_AES_128_GCM_SHA256 or can you just decrypt the public key then you don't need to bother with the private key.