AVM publishes instructions for FritzOS modification
A software developer has filed a lawsuit against the router manufacturer AVM with the support of the Software Freedom Conservancy (SFC). It was about providing source codes and instructions for modifying the FritzBox firmware.
Victory for both sides
The lawsuit will definitely give owners of FritzBox routers new options for customizing their devices. Nevertheless, a number of questions remain unanswered. But let’s start from the beginning: The software developer Sebastian Steck, supported by the Software Freedom Conservancy (SFC), has obtained important concessions in a legal dispute against the manufacturer AVM. The plaintiff originally wanted to make modifications to the firmware of a FritzBox 4020, but failed due to incomplete source code and missing instructions.
The lawsuit, based on the provisions of the Lesser General Public License (LGPL), sought to force AVM to release all necessary information. In particular, it was about the possibility of adapting the uClibc library licensed under LGPL and permanently installing the modified software on the router. As the SFC reports AVM gave in in the third month of negotiations and provided the requested information.
This included the full source code as well as scripts to control compilation and installation. The Berlin regional court will have one as early as July 2024 published the corresponding resolution (PDF). Nevertheless, there are further ambiguities in the case, because the SFC, as the plaintiff’s supporter, and AVM present the outcome of the lawsuit and the path that led there quite differently. For the end consumer, however, it is the result that counts, and that is interesting. Sebastian Steck summarizes the end of the complaint on his Foss Users website together:
The LGPL requires that recipients of the library be provided with the full source code, including the scripts to control the installation, so that the recipients can use the modified library with the applications to which the library was linked. In the Steck v. AVM case, the remaining issues were whether AVM must provide these installation scripts and whether Steck as a user – not the copyright owner – has standing to sue.
However, AVM preferred to provide the required installation scripts and thus settle the lawsuit. Nevertheless, AVM continues to claim that the source code originally provided was complete and does not make the installation scripts publicly available. Thanks to AVM, this question will remain unresolved until the next trial. James Cole
Consequences for the open source community?
The case still has far-reaching consequences for the open source community. It confirms that users have the right not only to modify licensed software on their devices, but also to permanently install these changes into flash memory.
AVM had initially argued that changes in volatile random access memory (RAM) were sufficient, but had to abandon this position. When creating the new instructions for exchanging files in the firmware image, AVM used tools from the Freetz Project back. For users of FritzBox routers, this means more freedom in customizing their devices. You can now theoretically implement your own functions or make security optimizations. However, this requires advanced technical knowledge and carries the risk of voiding the warranty. Sebastian Steck now has instructions for this that come from AVM published on his site.
AVM’s statement on the procedure
AVM emphasized in a statement Heise that the open source community has been actively supported for years as it ensures long-term innovation. The company sees itself as vindicated by the outcome of the proceedings, as “during the course of these proceedings it emerged that the source code was sufficient”.
