Patent 10592679 was granted and assigned to Apple (company) on March, 2020 by the United States Patent and Trademark Office.
Representative embodiments set forth herein disclose techniques for modifying encryption classes of files. According to some embodiments, a technique can include receiving a request to update an encryption configuration of a file from a current encryption class to an updated encryption class. In response, the technique involves obtaining (i) a first class key associated with the current encryption class, and (ii) a second class key associated with the updated encryption class. Next, the technique involves identifying file extents of the file, where each file extent is encrypted by a respective extent key that is encrypted by the first class key. Finally, the technique involves, for each file extent of the file: (i) decrypting the respective extent key using the first class key to produce a decrypted respective extent key, and (ii) encrypting the decrypted respective extent key using the second class key to produce an updated respective extent key.