摘要 |
This invention is generally concerned with methods, apparatus and computer program code for securely caching data, in particular for caching data stored on smart card systems such as those used in ICAO-compliant EU electronic passports. A caching system for providing a secure data cache for data stored in an electronic document, the caching system comprising: an input to receive data to be cached; a processor configured to use all or part of said received data to calculate a unique cryptographic key for said data; encrypt all or part of said data with said unique cryptographic key; and discard said unique cryptographic key after encryption and an output to send said encrypted data to a data cache, with decryption of encrypted data requiring said unique cryptographic key to be recalculated from said electronic document whereby said data cache is secure. Use of such a cache dramatically speeds up the inspection process, by bypassing the need to read data entirely, except for during the first inspection. |