Modes of Operation

How QNSP uses PQC primitives in different contexts.

Token signing

Algorithm: Dilithium (ML-DSA-65)

JWT Header: {"alg": "DILITHIUM3", "kid": "key-id"}
JWT Payload: {claims}
Signature: Dilithium.sign(header.payload, privateKey)

TLS key exchange

Algorithm: Hybrid X25519 + Kyber-768

ClientHello: X25519 + Kyber public keys
ServerHello: X25519 + Kyber ciphertexts
Shared secret: HKDF(X25519_ss || Kyber_ss)

Data encryption

Algorithm: AES-256-GCM with Kyber-wrapped DEK

1. Generate random DEK (256 bits)
2. Encapsulate DEK with Kyber public key
3. Encrypt data with DEK using AES-256-GCM
4. Store: Kyber ciphertext + AES ciphertext + tag

Document signing

Algorithm: Dilithium or SPHINCS+ (configurable)

1. Hash document with SHA3-256
2. Sign hash with Dilithium private key
3. Attach signature with algorithm identifier

Key wrapping

Algorithm: Kyber + AES-KWP

1. Generate ephemeral Kyber keypair
2. Encapsulate to get shared secret
3. Derive wrapping key from shared secret
4. Wrap target key with AES-KWP