Encrypt log filenames

[william-stacken]

For privacy, log filenames should be encrypted. But it should not be in a way that compromises the strength of the encryption scheme for the log contents. It should preferably also not increase the performance overhead too much.

One option is to generate a 16-byte IV, concatenate it with the AES-256-CBC encrypted filename, and base64 encode it. You could then decrypt all filenames by decoding the base64, treating the first 16 bytes as the IV, and the remainder as the encrypted filename. This means finding a particular log file turns into an O(n) operation since all files must be decrypted one by one until the correct file is found.