How to open password protected ePub file?

[praveen-jangre]

I am working on the ePub rendering engine. To achieve file/content protection, we have done file protection with a password.

Could you please help me open these password-protected files which are stored in the server as well as local storage?

Thank you in advance.

[johnfactotum]

It's not clear how you're password protecting the file, but in any case it wouldn't be something that's supported by Epub.js (unless you're encrypting the whole file after zipping, in which case just reverse that before feeding it to Epub.js).

The most proper way to do DRM would involve using encryption.xml, which Epub.js does not support (it doesn't even deobfuscate fonts). If you use something like that, you'd need to decrypt it yourself and serve the EPUB unpacked to Epub.js (i.e. opening it as a directory or .opf or .json).