Struct SessionKeys 

pub struct SessionKeys {
    pub initiator_key: SessionKey,
    pub responder_key: SessionKey,
    pub handshake_hash: [u8; 32],
    pub rekey_auth_key: [u8; 32],
}

Available on crate feature crypto only.

Session keys derived from the Noise handshake.

Per 1-SECURITY.md:

(initiator_key, responder_key) = HKDF-Expand(
    handshake_hash,
    "nomad v1 session keys",
    64
)

Additionally, for PCS (Post-Compromise Security), we derive:

rekey_auth_key = HKDF-Expand(
    static_dh_secret,   // DH(s_initiator, S_responder)
    "nomad v1 rekey auth",
    32
)

Fields

initiator_key: SessionKey

Key for initiator → responder messages

responder_key: SessionKey

Key for responder → initiator messages

handshake_hash: [u8; 32]

The handshake hash (stored for rekeying)

rekey_auth_key: [u8; 32]

Rekey authentication key for PCS (derived from static DH)

Implementations

impl SessionKeys

pub fn derive( result: &HandshakeResult, static_dh_secret: &[u8; 32], ) -> Result<Self, CryptoError>

Derive session keys from the handshake result and static DH secret.

Uses SHA-256 HKDF-Expand with the handshake hash as PRK for session keys, and the static DH secret for the rekey authentication key (PCS).

Arguments

• result - The handshake result containing the handshake hash
• static_dh_secret - The DH(s_initiator, S_responder) shared secret

impl SessionKeys

pub fn send_key(&self, role: Role) -> &SessionKey

Get the send key for the given role.

pub fn recv_key(&self, role: Role) -> &SessionKey

Get the receive key for the given role.