LCP DRM - Extracting Files

[edent]

I think I've discovered a way to extract files from an ePub or PDF which has LCP Profile 2.0.

This research is a proof-of-concept. It requires Linux and is not automated. This doesn't reverse engineer the encryption or reveal the cryptographic keys.

While this works on my machine, I don't know how generally useful it is.

My blog post is at https://shkspr.mobi/blog/2025/03/tow...rotected-epub/

[odamizu]

Interesting. And what I found the most interesting about the blog post is the statement from the Readium consortium that "Kobo support [for LCP] is coming" ...

[maddz]

Originally Posted by odamizu

Interesting. And what I found the most interesting about the blog post is the statement from the Readium consortium that "Kobo support [for LCP] is coming" ...

Yes, that's what NetGalley told me when they made the switch to LCP and sent comms out last month. No comment from Kobo as yet though.

[ownedbycats]

We were planning to now focus on new accessibility features on our open-source Thorium Reader, better access to annotations for blind users and an advanced reading mode for dyslexic people. Too bad; disturbances around LCP will force us to focus on a new round of security measures, ensuring the technology stays useful for ebook lending (stop reading after some time) and as a protection against oversharing.

Using accessibility as a gotcha? I raise my middle finger to them.

[JSWolf]

I hope that Kobo keeps well away from LCP. I want nothing to do with it.

[ownedbycats]

Originally Posted by JSWolf

I hope that Kobo keeps well away from LCP. I want nothing to do with it.

I hope that publishers freking eventually figure out that DRM is pointless for anti-piracy.

[Byrdie]

I do not buy -- or should I say rent? -- audiobooks from Kobo because of their "no downloading/only in our app" nonsense. If they go along with this LCP horsepuckey then guaranteed I won't be buying any more ebooks from them either.

[Aleron Ives]

The hope is that Kobo will be adding LCP but not removing ADE support in the process. Since ADE is necessary for most libraries, that seems likely for the time being.

[odamizu]

Originally Posted by Aleron Ives

The hope is that Kobo will be adding LCP but not removing ADE support in the process. Since ADE is necessary for most libraries, that seems likely for the time being.

Though they could keep ADE solely for library loans and switch to LCP for purchased ebooks and NetGalley.

[kandwo]

Originally Posted by ownedbycats

I hope that publishers freking eventually figure out that DRM is pointless for anti-piracy.

It seems like it's the DRM world's equivalent to "think of the children" or "terrorists!".

Swedish libraries have started using LCP in the name of "accessibility" and don't allow downloads of books anymore (even though it would be possible using LCP, see Thorium et al.). Their reading app/website is so basic as to make Kindle look super customizable.

Congrats! Now your books are so accessible that they're impossible to read.

(As we all know, being able to customize fonts or margins is inaccessible and EVIL!)

All DRM is bad and I really dislike these readium fellows in particular due to their hiding behind "open source" and "accessibility". "If we're not doing it, somebody even worse would be in charge!" Yeah, I'm not buying it.

[maddz]

Originally Posted by odamizu

Though they could keep ADE solely for library loans and switch to LCP for purchased ebooks and NetGalley.

But the Readium people said LCP is for lending - why should people buying a book have it imposed on their purchase? Back when I purchased pbooks, bookshops and publishers didn't dictate what I did with my purchase or how and where I read it, why should they do that with electronic copies?

I mean, an ebook is useless if you're reading in the loo and the loo roll has run out...

[Aleron Ives]

Originally Posted by maddz

Back when I purchased pbooks, bookshops and publishers didn't dictate what I did with my purchase or how and where I read it, why should they do that with electronic copies?

Because they can? Publishers hate that they don't have total control over paper books, and thus far nobody has mounted a successful effort to curtail their greed when it comes to e-books.

[Quoth]

Originally Posted by ownedbycats

I hope that publishers freking eventually figure out that DRM is pointless for anti-piracy.

Yes. Absolutely.

[Quoth]

Originally Posted by Aleron Ives

Because they can? Publishers hate that they don't have total control over paper books, and thus far nobody has mounted a successful effort to curtail their greed when it comes to e-books.

Other than Amazon wanting to have the entire retail market and be a publisher too

I'm thinking that's not the successful effort you are wanting.

[JSWolf]

Originally Posted by odamizu

Though they could keep ADE solely for library loans and switch to LCP for purchased ebooks and NetGalley.

Kobo will still have KePub. Unless Kobo makes KePub LCP infected. If Kobo doesn't make KePub LCP infected, they'd need to add a third renderer to handle LCP.