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Do not Restrict Me! How copy protection (DRM) on e-books harms our freedom and what to do about it

Part I: DRM Hell

Like many people, I like reading books. My favourite genre is science fiction, but I also like the occasional gay romance and I love to diversify by reading books in different languages. My home isn't too spacious, and with two completely filled-up bookcases there's little room left for more physical books, so I've hopped on the e-book bandwagon over a decade ago, I generally prefer things to be digital anyway. However, my love for all things digital is significantly dampened by the nastiness that is DRM (Digital Rights Management), the copy protection that encumbers the majority of e-books nowadays.

Me in front of my bookcases a few years ago

I've been using a Kobo Aura e-reader for a long time, Over the years, I have bought my fair share of books. Getting them from the Kobo store or the Dutch (which has some kind of partnership with Kobo) onto the reader was a breeze. Most consumers would be happy with such an experience, but for me there was always this nagging feeling that I was being locked into an ecosystem and never really own the books I bought.

What if my e-reader breaks? What if Kobo or Adobe goes bankrupt? Would I still have access to all the books I bought? All my physical books will still be there even in 50 years or so unless they befall to fire, burglary, rising sea levels, or paper-devouring bookworms. With my normal digital data, I take care to ensure similar longevity by making frequent backups and storing them in simple interoperable formats that pass the test of time (like plain text, HTML, etc). DRM encumbered data, however, is not normal digital data, it is encrypted data. You can't read it without having the proper key. Now data encryption as such is fine and something I'm a big proponent and heavy user of, but it stands or falls on who has ownership of the key! Spoiler alert, with DRM it's not you!

A stack of books with keys on top

When it comes to e-books with DRM, books are typically encrypted with a key personalized for you, but you don't own the personalized key to decrypt your own books. Worse, the whole technology relies on obfuscation of this decryption key. The use of obfuscation in data security is flawed in principle, there will always be clever people capable of breaking it (this is also the case for DRM). DRM is a flawed technological solution for what is in fact a legal or socio-economic problem.

The legal issue is that of copyright, the author or publisher of a book has the exclusive right to sell copies of his/her own work, others are not permitted to do so. This sounds fair enough to me. The creator who created the work should be the one receiving the monetary gains from it, if he/she so desires. The challenge is, whereas a physical book needs to be printed and shipped to the customer, a digital resource copies effortlessly and can be sent all over the world in no time. This means there is no longer any significant scarcity involved in the distribution process from which value can be derived.

Those who enforce DRM upon us attempt to keep an old business model alive where distribution was coupled to creation and tightly controlled, but this no longer works. The only way to do so in a digital age is to place ever-further restrictions on the user. When you watch a movie in a movie theatre, as opposed to from your own home, you are in a fairly tightly controlled environment. You play by the rules of the theatre and you pay essentially for a (single) viewing experience. DRM software does something similar, it builds a tightly controlled virtual theatre for you within the constraints of which you are allowed to do your viewing. It never really works though, everything that you see on your screen or hear from your speakers can in principle be copied. As cumbersome as it might be, it's theoretically possible to make photographs of pages of your DRM-protected book on your e-reader and then have the text extracted via OCR (optical character recognition), or to record an audio/video stream with a microphone and camera. In a real movie theatre there are rules against this: you're under some form of surveillance, you'll probably be be kicked out if you start recording the movie from your smartphone. In the software theatres that DRM forces you into, you're under an ever-encroaching kind of surveillance too and you are shipped a crippled product that is defective by design. The core tenet is: the user/consumer can not be trusted and the rights of the producer outweigh the rights of the consumer.

The use of DRM means that only software that implements proprietary DRM technology like Adobe DRM, can decrypt the book on your behalf and show it. This is also how e-readers do it. Such software is, probably by contract with the supplier of the DRM technology, bound to all kinds of restrictions designed to keep the actual data as far away from the user as possible. Such software is by definition fundamentally incompatible with the free and open source software that I cherish and choose to use. DRM relies on obfuscation, openness and freedom is its anti-thesis, DRM requires proprietary software libraries that usually come with a licensing fee to be paid by whoever builds the viewer software to the DRM technology supplier. DRM in itself is an industry, and whereas supporting the authors that write the books I love is something I whole- heartedly support, a major share of the profit ends up not with the author but with publishers and platforms whose practises I do oppose.

More and more, our devices impact our privacy and monitor how we use them. Knowing exactly what books we read (or what music we listen, videos we watch) is a treasure trove for parties like Amazon, Google, Apple, Kobo, etc.. because it allows them to 1) recommend and sell more similar books to us and 2) build up a profile of our interests which has value (= can be sold) to anyone who wants to target us with advertisements.

In democratic societies we tend to value freedom of opinion, without it our democratic societies could not exist. The books we read, the information we consume, are pivotal in a free society and says a lot about us. It may also divulge a lot about us to potential adversaries (political or otherwise). It is not a coincidence that dictatorships often start with book bannings and burnings. I therefore think it is fundamentally important that information on our reading habits and media consumption in general is not collected by any one or few major players, be it companies or governments. The potential for abuse is just too great.

BramhHall 2018 - New York Daily News

Technologies like DRM, aside from being technically flawed in principle, also provide the wrong incentives, they hinder interoperability and lead to the emergence of one or a few centralised solutions. Those who control these solutions then sit on a treasure trove of potential data that is just waiting to be exploited. They also hinder any alternative legitimate use I might have on the books I buy, say I want to do scientific research by doing some kind of statistical analysis on the text, or some kind of annotation on the text. I am a research software developer developing precisely such (open) software. But all of this is not possible on DRM encumbered e-books as the actual text is being deliberately kept as far away from me as possible!

Likewise, I can't just build an open e-reader software myself, say based on postmarketOS and SXMO, both of which have been successfully tried on a Kobo Clara HD, because it would not be able to open anything touched by DRM, making it pretty useless for the average consumer. I'd be very interested in trying if I can get something like this working on my Kobo Aura and read my books using our own Sxmo system! Or what if I wanted to build a search index to search in the text of all the books I own? If it were not for DRM, I could easily build this, but DRM makes me reliant on third-party proprietary software. Normal competition is stifled as the DRM provider acts as a gatekeeper that demands the user can only access a crippled defective version of the actual product.

Part II: Do not Restrict me!

Readers against DRM - by RAD! initiative

I'm writing all of this because my Kobo reader has been having some difficulties lately so I decided to look for a replacement. This opened the gates to the DRM hell I depicted above.

Being aware of the ecosystem I was being locked into, I decided this was a good moment to break with it and opt for more freedom and sustainability. I chose a Pocketbook e-reader (the PocketBook Inkpad Color 3 to be precise) as this brand seems to be one of the few e-readers that isn't as tied to a store as for example Amazon Kindles (they are the worst) or, to lesser extend, Kobo devices are. It's a device that can still be fully used without requiring you to log in with some kind of cloud account. The exception being of course DRM, the device supports Adobe's DRM technology and you need an Adobe ID if you want to be able to read books tainted by it. I reluctantly registered such an account.

So how do I transfer the DRM books I have on my old Kobo to my new Pocketbook? I can't grab the EPUB files from the Kobo because they'd be encrypted specifically for that device using Kobo's own DRM scheme. Stores like Kobo and have a download option. This suggests you can download the e-books but in fact, in case of Adobe DRM encumbered e-books you don't even get the encrypted EPUB files, but you get so-called ACSM files (Adobe Content Server Message) instead. These are not the actual book but is merely a receipt that a client can in turn send to Adobe's server to obtain the (encrypted) book. The message contains information such as your personal UUID and Adobe account details.

My PocketBook e-reader is supposed to support these ACSM files and obtain the encrypted DRM-encumbered books for me. This would be the obvious route for the normal user. However, it didn't work for some unknown reason: I got a cryptic E_ADEPT_NO_FULFILLMENT_RESULT error when trying to open the ACSM files directly on my new reader. This shows that the technology is fragile and that if things break, there's not much you can do. For any normal non-technical user things would have already gotten too difficult by now.

Fortunately I'm not a non-technical user and I don't give up easily, my next try was to go via a program called "Adobe Digital Editions", this is proprietary software that can read these ACSM files and obtains the encrypted EPUB file for you. Both in this program as well as on the device, I register the same Adobe ID, and then the encrypted EPUB files this program downlods can be transferred and decrypted/displayed by the e-reader.

A major caveat is that Adobe Digital Editions is proprietary software that is available (free of charge), but only for Windows or macOS, or for Android or iOS nowadays as well. But I have none of those systems nor intend to buy any of them just so I can access my books! As a FOSS enthusiast I run on Linux systems exclusively.

There's a solution though, I (again, reluctantly) installed Adobe Digital Editions 4.5 via Wine on my Arch Linux system. I'll guide you to the steps in case anybody finds themselves in a similar conundrum:

  1. On Arch Linux, first enable multilib so you can install 32-bit software like Wine on a 64-bit system.
  2. Then install wine and various dependencies you might need: pacman -Syu wine winetricks wine-mono lib32-gnutls samba
  3. Set a new WINEPREFIX and WINEARCH: export WINEPREFIX=~/.adewine/ WINEARCH=win32
  4. Create the WINEPREFIX: winecfg
  5. Install Adobe Digital Editions 4.5 via winetricks: winetricks -q adobe_dige4
  6. Start Adobe Digital Editions: WINEPREFIX=~/.adewine WINEARCH=win32 wine $WINEPREFIX/drive_c/Program\ Files/Adobe/Adobe\ Digital\ Editions\ 4.5/DigitalEditions.exe
  7. Register your Adobe ID in the program.

If that is all done, you can now import ACSM files in Adobe Digital Editions. It will use the query the Adobe server to obtain the actual encrypted book and puts encrypted EPUB or PDF files in a directory My Digital Editions in C:\users\$USERNAME\Documents\. If you are lucky this is already mapped to your ~/Documents. These you can transfer to your e-reader. You can also let Adobe Digital Editions transfer things to your e-reader but I didn't try that as I prefer to let it do as little as possible and didn't want to go into the hassle of getting a USB device accessible via wine.

At this point I finally managed to get my encrypted books onto the e-reader and the e-reader actually manages to open them. But... the books are still tainted by DRM which is not what I want.

As DRM is a flawed technology to begin with, it should not be surprising that it has been reverse engineered and broken. For Adobe ADEPT DRM this was initially published back in 2009 by a user under the pseudonym i♥cabbages. This software has been integrated into DeDRM-tools, which is a plugin for the open source e-book management software Calibre. On Arch Linux, install calibre with pacman -Syu calibre and install the plugin from the Arch User Repository with yay -S calibre-plugin-dedrm (or whatever other AUR helper you use).

I recommend you launch calibre from a terminal so you can see its standard error output.

If Adobe Digital Editions is installed and you now import a DRM-protected EPUB, i.e. the ones you got from Adobe Digital Editions, the DeDRM plugin will automatically extract the encryption key from the Adobe Digital Editions installation and subsequently decrypt the book. The resulting EPUB will finally be a normal one which you can read anywhere.

All files are provided - DRM Free - without restrictive technologies (Defective by Design, Free Software Foundation)

The caveat again is that this a bit tricky to get working since we run Adobe Digital Editions in Wine. In the Calibre plugin settings for DeDRM tools, you need to explicitly set the wine prefix to ~/.adewine. Moreover, the DeDRM scripts are written in Python and some of them will have to run inside Wine, so we need a Python installation in our WINEPREFIX, I installed one as follows:

  1. Grab a 32-bit Windows installer version of Python 3: wget
  2. Run the installer WINEPREFIX=~/.adewine WINEARCH=win32 wine python-3.7.8.exe.
  3. Install the required cryptography module for Python: WINEPREFIX=~/.adewine WINEARCH=win32 wine ~/.adewine/drive_c/users/$USER/AppData/Local/Programs/Python/Python37-32/python.exe -m pip install pycryptodome
  4. Launch calibre, (make sure to set the wine prefix in the plugin configuration screen for DeDRM-tools), then import your DRM EPUBs.
  5. The resulting EPUBs in your Calibre Library directory will now be fully decrypted, i.e. not tainted by DRM. You can transfer them to your e-reader or open them with any normal EPUB viewer anywhere!
  6. Make sure to export your extracted key from Calibre's plugin configuration screen for DeDRM-tools. This will be produce a der file. It ensures that even if Adobe at some point changes their obfuscation algorithm so key extraction no longer works, you still have the decrypted key and can import it back.

When removing DRM you must of course take care not to redistribute/share the resulting files, that would be a clear violation of copyright law anywhere. I explicitly do NOT advocate for NOR encourage you to violate such laws, I merely advocate for software freedom, proper interoperability, long term sustainability, consumer privacy and freedom from surveillance. I argue against DRM technology because it is is detrimental to all those things and technologically faulty by design because it relies on obfuscation.

As to the legality of removing DRM from your own e-books without redistributing them, I am by no means a lawyer, but you can read this article that provides a fairly thorough perspective: Is removing DRM illegal? Demystifying the Legality of Removing Digital Rights Management.

Last, but not least, I would like to urge the reader to seek out those publishers and authors that sell DRM-free books and buy books from them whenever possible. A notably one in the Science Fiction genre is Tor Books (not to be confused with the Tor Network which is completely unrelated). Notable DRM-free stores are Smashwords and Lulu, see Guide to DRM-Free Living: Literature for more.

Credits and references


Adobe, Amazon, Google and all those many others enforcing DRM technology on end-users.


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