Extracting content from an LCP "protected" ePub

As Cory Doctorow once said "Any time that someone puts a lock on something that belongs to you but won't give you the key, that lock's not there for you." But here's the thing with the LCP DRM scheme; they do give you the key! As I've written about previously, LCP mostly relies on the user entering their password (the key) when they want to read the book. Oh, there's some deep cryptographic magic in the background but, ultimately, the key is sat on your computer waiting to be found. Of course, cryptography is Very Hard™ which make retrieving the key almost impossible - so perhaps we can use a different technique to extract the unencrypted content? One popular LCP app is Thorium. It is an Electron Web App. That means it is a bundled browser running JavaScript. That also means it can trivially be debugged. The code is running on your own computer, it doesn't touch anyone else's machine. There's no reverse engineering. No cracking of cryptographic secrets. No circumvention of any techni ... Read full article.