Introduction

libgourou is a free implementation of Adobe's ADEPT protocol used to add DRM on ePub/PDF files. It overcome the lacks of Adobe support for Linux platforms.

Architecture

Like RMSDK, libgourou has a client/server scheme. All platform specific functions (crypto, network...) has to be implemented in a client class (that derives from DRMProcessorClient) while server implements ADEPT protocol. A reference implementation using Qt, OpenSSL and libzip is provided (in utils directory).

Main fucntions to use from gourou::DRMProcessor are :

• Get an ePub from an ACSM file : fulfill() and download()
• Create a new device : createDRMProcessor()
• Register a new device : signIn() and activateDevice()

You can import configuration from (at least) :

• Kobo device : .adept/device.xml, .adept/devicesalt and .adept/activation.xml
• Bookeen device : .adobe-digital-editions/device.xml, root/devkey.bin and .adobe-digital-editions/activation.xml

Or create a new one. Be careful : there is a limited number of devices that can be created bye one account.

ePub are encrypted using a shared key : one account / multiple devices, so you can create and register a device into your computer and read downloaded (and encrypted) ePub file with your eReader configured using the same AdobeID account.

For those who wants to remove DRM, you can export your private key and import it within Calibre an its DeDRM plugin.

Dependencies

For libgourou :

• None

For utils :

• QT5Core
• QT5Network
• OpenSSL
• libzip

Compilation

Use make command

make [CROSS=XXX] [DEBUG=(0*|1)] [STATIC_UTILS=(0*|1)] [BUILD_UTILS=(0|1*)] [BUILD_STATIC=(0*|1)] [BUILD_SHARED=(0|1*)]

CROSS can define a cross compiler prefix (ie arm-linux-gnueabihf-)

DEBUG can be set to compile in DEBUG mode

BUILD_UTILS to build utils or not

STATIC_UTILS to build utils with static library (libgourou.a) instead of default dynamic one (libgourou.so)

BUILD_STATIC build libgourou.a if 1, nothing if 0, can be combined with BUILD_SHARED

BUILD_SHARED build libgourou.so if 1, nothing if 0, can be combined with BUILD_STATIC

• Default value

Utils

You can import configuration from your eReader or create a new one with utils/activate :

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$PWD
./utils/activate -u <AdobeID USERNAME>

Then a ./.adept directory is created with all configuration file

To download an ePub/PDF :

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$PWD
./utils/acsmdownloader -f <ACSM_FILE>

To export your private key :

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$PWD
./utils/acsmdownloader --export-private-key [-o adobekey_1.der]

Copyright

Grégory Soutadé

License

libgourou : LGPL v3 or later

utils : BSD

Special thanks

• Jens for all test samples and utils testing