Data storage circuitry for securely storing confidential data and a data processing apparatus for processing and storing the data and a method are disclosed. The data storage circuitry comprises: a data store comprising a plurality of data storage locations for storing data; an input for receiving requests to access the data store; renaming circuitry for mapping architectural data storage locations specified in the access requests to physical data storage locations within the data store; encryption circuitry for encrypting data prior to storing the data in the data store, the encryption circuitry being configured to generate an encryption key in dependence upon a physical data storage location the data is to be stored in; and decryption circuitry for decrypting data read from the data store, the decryption circuitry being configured to generate a decryption key in dependence upon the physical data storage location the data is read from.