Struct KemUpgradeProtocol 

pub struct KemUpgradeProtocol {
    pub local: KemConfig,
    pub remote: KemConfig,
    pub result: KemNegotiationResult,
}

KEM upgrade protocol: runs after Noise XX handshake completes, before sync streams are opened.

When both peers support ML-KEM-768, the upgrade must complete before any sync stream traffic begins, protecting against store-now-decrypt-later attacks.

Fields

local: KemConfig

Local KEM config.

remote: KemConfig

Remote KEM config (from WeftHandshake).

result: KemNegotiationResult

Negotiation result.

Implementations

impl KemUpgradeProtocol

pub fn new(local: KemConfig, remote: KemConfig) -> Self

Create a new KEM upgrade protocol from local and remote configs.

pub fn requires_upgrade(&self) -> bool

Whether sync streams should wait for KEM to complete.

Returns true when both sides support KEM, meaning the PQ key exchange MUST finish before any sync traffic flows.

pub fn execute(&self, classical_secret: Vec<u8>) -> HybridKeyExchange

Execute the KEM exchange, combining the classical Noise secret with the post-quantum shared secret (when both sides support it).

In the current placeholder implementation, the PQ secret is derived deterministically from the remote KEM public key. A real implementation would use ML-KEM-768 encapsulate/decapsulate.