Crypto Policy

The crypto policy interface dictates the various behaviors of Asherah and can be configured with the below options:

canCacheSystemKeys
- enables/disables caching of System Keys
canCacheIntermediateKeys
- enables/disables caching of Intermediate Keys
canCacheSessions
- enables/disables caching of Sessions
getSessionCacheMaxSize
- the maximum numbers of sessions to cache
getSessionCacheExpireMillis
- the time period to expire the sessions present in the cache
getRevokeCheckPeriodMillis
- the time period to revoke keys present in cache
isKeyExpired
- defines if a key is expired
keyRotationStrategy
- defines the key rotation strategy; enumeration of INLINE, QUEUED.
notifyExpiredSystemKeyOnRead
- enables/disables notifications for expired System Key.
notifyExpiredIntermediateKeyOnRead
- enables/disables notifications for expired Intermediate Key.

Implemented Policies

This policy has some suggested pre-configured defaults which can be optionally overridden. The two required properties for this policy are:

keyExpirationDays: The number of days after which a key will expire. This is tied to the isKeyExpired interface method. If a key is expired, the old key is used to decrypt the data. Depending on the crypto policy configuration it is then rotated inline on the next write or queued for renewal (not implemented as of this writing).
revokeCheckMinutes: Keys are cached to minimize calls to external datastores for fetching and decrypting keys. This property sets the cache's TTL and is needed in case we chose to revoke the keys in the cache. This is tied to the getRevokeCheckPeriodMillis interface method.

This policy supports keys that neither expire nor are removed from the cache. This should never be used in the production environment.