A device includes a key store memory that stores one or more cryptographic keys. A rule set memory stores a set of rules for accessing the cryptographic keys. A key store arbitration module grants access to the cryptographic keys in accordance with the set of rules. The device can be used in conjunction with a key ladder. The device can include a one-time programmable memory and a load module that transfers the cryptographic keys from the one one-time programmable memory to the key store memory and the set of rules to the rule set memory. A validation module can validate the cryptographic keys and the set of rules stored in the key store and rule set memories, based on a signature defined by a signature rule.