Hi. You're right, it is a block cipher. KEF how I designed it file format where all the relevant information (such as cipher information, the file size, MD5 ch

Hi. You're right, it is a block cipher. KEF how I designed it file format where all the relevant information (such as cipher information, the file size, MD5 checksum and mime content type, whether or not 2 or more passphrases are used and a number array containing the length of each file) is in the header itself. The rest is basically information like the randomly generated Tag/IV is prepended to the encrypted data itself. The plugin is using OpenSSL's encrypting function but theoretically, it can work with any encryption software that produces the Tag and the IV. As for the ranges of data, this is basically the bytes that will be decrypted and sent to the user. This allows for web browsers that send range headers to receive the portion of data without decrypting the whole thing. If you're down to program the script of course. Hope this helps. EDIT: I am open to critique, I don't know how to describe the functionality of my plugin. I am researching on how to include unit tests.