Struct MasterKeySet 

pub struct MasterKeySet {
    pub k_tag: SecretKey,
    pub k_val: SecretKey,
    pub k_state: SecretKey,
    pub k_srch: SecretKey,
}

The four secret keys that drive the entire RO(SE)² protocol. All four are derived deterministically from a user password + salt, so they can be re-derived on any device that knows the password.

Fields

k_tag: SecretKey

K_tag — derives EDB entry addresses (tags). tag = HMAC-SHA256(k_tag, "tag:" || keyword || index || epoch)

k_val: SecretKey

K_val — encrypts document payloads stored in EDB entries. val_key = HMAC-SHA256(k_val, "val:" || keyword || index || epoch)

k_state: SecretKey

K_state — encrypts the local ClientStateTable before persistence.

k_srch: SecretKey

K_srch — derives per-search blinding factors (used in SWiSSSE phase).

Implementations

impl MasterKeySet

pub fn derive(password: &str, salt: &[u8; 16]) -> Result<Self, VaultError>

Derive a full MasterKeySet from a UTF-8 password and a 16-byte salt.

The salt must be unique per vault and stored alongside the encrypted state. It does NOT need to be secret.

Errors

Returns VaultError::Kdf if Argon2 parameters are rejected (internal).