Patent ID: 8200964

Claim:
A method for accessing an encrypted file through a file system, comprising: mounting the file system, wherein mounting the file system comprises inputting a master secret in a tamper-resistant module; receiving a request at the file system to access the encrypted file, wherein the encrypted file and an encrypted file key for the encrypted file are stored in the file system; in response to the request, sending the encrypted file key for the encrypted file from the file system to the tamper-resistant module outside of, and physically separate from, the file system, wherein the tamper-resistant module does not store the encrypted file or the encrypted file key for the encrypted file; using the master secret to decrypt the encrypted file key at the tamper-resistant module to restore the file key; wherein the master secret is obtained from an external source by the tamper-resistant module, and wherein the master secret is not stored in a memory within a computer system in which the file system operates, and hence the file system never has access to the master secret; and using the file key to access the encrypted file.