SC-CFS: Smartcard Secured Cryptographic File System

Storing information securely is one of the most important roles expected for computer systems, but it is difficult to achieve with current commodity computers. The computers may yield secrets through physical breach, software bug exploitation, or password guessing attack. Even file systems that provide strong security, such as the cryptographic file system, are not perfect against these attacks. We have developed SC-CFS, a file system that encrypts files and takes advantage of a smartcard for per-file key generation. SC-CFS counters password guessing attack, and minimizes the damage caused by physical attack and bug exploitation. The performance of the system is not yet satisfactory, taking 300 ms for accessing a file.