Struct CacheDb 

pub struct CacheDb { /* private fields */ }

Encrypted cache database wrapper.

Stores non-authoritative, regenerable data (proof cache, session keys, replay guard) to improve performance without affecting correctness if rebuilt.

Implementations

impl CacheDb

pub fn new( path: &Path, k_intermediate: [u8; 32], _lock: &StorageLockGuard, ) -> StorageResult<Self>

Opens or creates the encrypted cache database at path.

If integrity checks fail, the cache is rebuilt since its contents can be regenerated from authoritative sources.

Errors

Returns an error if the database cannot be opened or rebuilt.

pub fn merkle_cache_get( &self, valid_until: u64, ) -> StorageResult<Option<Vec<u8>>>

Fetches a cached Merkle proof if it remains valid beyond valid_before.

Returns None when missing or expired so callers can refetch from the indexer without relying on stale proofs.

Errors

Returns an error if the query fails.

pub fn merkle_cache_put( &mut self, _lock: &StorageLockGuard, proof_bytes: Vec<u8>, now: u64, ttl_seconds: u64, ) -> StorageResult<()>

Inserts a cached Merkle proof with a TTL. Uses the database current time for inserted_at.

Existing entries for the same (registry, root, leaf index) are replaced.

Errors

Returns an error if the insert fails.

pub fn session_key_get( &self, rp_id: [u8; 32], ) -> StorageResult<Option<[u8; 32]>>

Fetches a cached session key if present.

This value is the per-RP session seed (aka session_id_r_seed in the protocol). It is derived from K_intermediate and rp_id and is used to derive the per-session r that feeds the sessionId commitment. The cache is an optional performance hint and may be missing or expired.

Errors

Returns an error if the query fails.

pub fn session_key_put( &mut self, _lock: &StorageLockGuard, rp_id: [u8; 32], k_session: [u8; 32], ttl_seconds: u64, ) -> StorageResult<()>

Stores a session key with a TTL.

The key is cached per relying party (rp_id) and replaced on insert.

Errors

Returns an error if the insert fails.

pub fn is_nullifier_replay( &self, nullifier: [u8; 32], now: u64, ) -> StorageResult<bool>

Checks whether a replay guard entry exists for the given nullifier.

Returns

• bool: true if a replay guard entry exists (hence signalling a nullifier replay), false otherwise.

Errors

Returns an error if the query to the cache unexpectedly fails.

pub fn replay_guard_set( &mut self, _lock: &StorageLockGuard, nullifier: [u8; 32], now: u64, ) -> StorageResult<()>

After a proof has been successfully generated, creates a replay guard entry locally to avoid future replays of the same nullifier.

Errors

Returns an error if the query to the cache unexpectedly fails.

Trait Implementations

impl Debug for CacheDb

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.