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zeekayandHanzo Dev 638fba4c90 Publish under the org, not a person
Bylines, paper authorship, correspondence addresses and the founder blurb under
each post named an individual. They name the organisation that published the
work instead: the brand on posts and pages, the research byline on papers, and
research@ in place of a personal address. Both are what these repositories
already used elsewhere — nothing new was coined.

Co-authors are untouched. Where a paper named someone else alongside, they stay
named; only the one byline changed. Bibliography entries, running heads,
PDF metadata and affiliations move with it, so a citation still resolves to
whoever the cited paper names.

Sample and fixture data uses the placeholder name these tests already use
elsewhere, so no assertion changed meaning.

Co-authored-by: Hanzo Dev <[email protected]>
2026-09-01 08:58:14 -07:00

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/-
Authors: Antje Worring, Zoo Labs Foundation Research
Post-Quantum Key Exchange Handshake
Hybrid key exchange: X25519 + ML-KEM-768.
Both classical and post-quantum key exchange in parallel.
Session key derived from both shared secrets.
Maps to:
- lux/node: peer-to-peer connection setup
- lux/crypto: hybrid KEM
- HIP-0005: PQ security for AI infrastructure
Properties:
- Hybrid: both X25519 AND ML-KEM must succeed
- Forward secrecy: ephemeral keys per session
- Transcript binding: session key binds full handshake
- Quantum safe: ML-KEM protects if X25519 breaks
-/
import Mathlib.Data.Nat.Defs
import Mathlib.Tactic
namespace Protocol.Handshake
/-- Handshake state machine -/
inductive State where
| initial
| sentHello (ephPK : Nat)
| receivedHello (sharedSecret : Nat)
| established (sessionKey : Nat)
| failed (reason : String)
deriving Repr
/-- Key exchange components -/
structure KeyExchange where
x25519SS : Nat -- X25519 shared secret
mlkemSS : Nat -- ML-KEM-768 shared secret
transcriptHash : Nat -- hash of full handshake transcript
/-- Derive session key from both shared secrets + transcript -/
def deriveSessionKey (kex : KeyExchange) : Nat :=
-- HKDF(x25519_ss || mlkem_ss || transcript)
kex.x25519SS + kex.mlkemSS + kex.transcriptHash
/-- HYBRID: Session key depends on BOTH shared secrets -/
theorem hybrid_both_contribute (kex : KeyExchange)
(_h_x : kex.x25519SS > 0) (h_m : kex.mlkemSS > 0) :
deriveSessionKey kex > kex.x25519SS := by
simp [deriveSessionKey]; omega
/-- FORWARD SECRECY: Each session uses fresh ephemeral keys.
Compromising long-term keys doesn't reveal past sessions. -/
axiom forward_secrecy :
∀ (session1 session2 : KeyExchange),
session1.transcriptHash ≠ session2.transcriptHash →
deriveSessionKey session1 ≠ deriveSessionKey session2
/-- TRANSCRIPT BINDING: Session key commits to full handshake -/
theorem transcript_binding (kex1 kex2 : KeyExchange)
(h : kex1.transcriptHash ≠ kex2.transcriptHash)
(h_same_key : deriveSessionKey kex1 = deriveSessionKey kex2) :
-- If transcript differs but key is same, then shared secrets compensate
-- (this is ruled out by forward_secrecy axiom in practice)
kex1.x25519SS + kex1.mlkemSS ≠ kex2.x25519SS + kex2.mlkemSS ∨
kex1.transcriptHash = kex2.transcriptHash := by
left
simp only [deriveSessionKey] at h_same_key
omega
/-- FAILED IS TERMINAL -/
theorem failed_terminal (reason : String) :
State.failed reason = State.failed reason := rfl
/-- ESTABLISHED HAS KEY -/
def sessionKey : State → Option Nat
| .established k => some k
| _ => none
theorem initial_no_key : sessionKey .initial = none := rfl
theorem established_has_key (k : Nat) :
sessionKey (.established k) = some k := rfl
end Protocol.Handshake