Instead, the organisation, in a white paper on Microsoft's secure boot proposal and the fallout thereof, said users should be able to both easily disable secure boot and to use their own security keys in order that they could be the ultimate decision-maker on which software should run on their computers.
FSF executive director John Sullivan said: "We will do what we can to help all free software operating system distributions follow this path, and we will work on a political level to reduce the practical difficulties that adhering to these principles might pose for expedient installation of free software.
"The FSF does want everyone to be able to easily install a free operating system - our ultimate goal is for everyone to do so, and the experience of trying out free software is a powerful way to communicate the importance of free software ideals to new people.
"But we cannot, in the name of expediency or simplicity, accept systems that direct users to put their trust in entities whose goal it is to extinguish free software. If that's the tradeoff, we better just turn Secure Boot off."
The white paper pointed out that its GPLv3 licence, the updated version of the GPLv2 under which the Linux kernel is issued, protected users against onerous requirements such as those being made in the name of secure boot; when one bought or rented a computer running GPLv3 software the licence protected one's right to run modified versions of that software on that computer.
"GPLv2 always required that users be able to do this, but one of the improvements in GPLv3 ensures that the freedoms all GPL versions are meant to provide can't be taken away by hardware that refuses to run modified software," Sullivan said.
Under the GPLv3 one was required to provide clear instructions and functionality for users to fully modify or disable boot restrictions so that they could run their own software on such a system.
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The FSF said that secure boot, if done right, embodied its own views on software security; it would give users the ability to remove any key from the boot firmware and add keys belonging to a software developer of their choice.
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Evaluating the methods to overcome secure boot advanced by Red Hat and Canonical (the maker of Ubuntu), the FSF came down on the side of Red Hat's method as being better since it depended on using GRUB2 in the bootloader chain; GRUB2 is issued under the GPLv3 licence.
Red Hat has joined a Microsoft and Verisign developer programme that enables purchase of a key that will enable the loading of a "shim" bootloader; this then chains to GRUB2 which boots the operating system kernel. As Fedora's key is from Microsoft, it can be recognised by the firmware on the majority of motherboards.
"There is much to like about Fedora's thinking, as explained by Matthew Garrett," Sullivan said. "Their process of deliberation evinced concern for user freedom; it's clear that the Fedora team sought a solution that would work not just for their own GNU/Linux distribution, but for as many free software users and distributions as possible.
"Their discussion was also mindful of the desirability of empowering users to sign and run their own modified software without being treated as second-class citizens. Unsurprisingly, with those concerns guiding their thinking, they have ended on a proposal which as described is compliant with GPLv3."
But the FSF said depending on a Microsoft key was a weakness of this method as was the recommendation that others join the developer programme to obtain their own keys.
The approach taken by Canonical was viewed with concern by the FSF as the company had chosen to avoid using GRUB2 thus leaving the user vulnerable as the protections available under the GPLv licence were not available to the user.
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"Our main concern with the Ubuntu plan is that because they are afraid of falling out of compliance with GPLv3, they plan to drop GRUB 2 on Secure Boot systems, in favor (sic) of another bootloader with a different license that lacks GPLv3's protections for user freedom," Sullivan said.
"Their stated concern is that someone might ship an Ubuntu Certified machine with Restricted Boot (where the user cannot disable it). In order to comply with GPLv3, Ubuntu thinks it would then have to divulge its private key so that users could sign and install modified software on the restricted system."
Sullivan said this was unfounded and based on a misunderstanding of GPLv3. "We have not been able to come up with any scenario where Ubuntu would be forced to divulge a private signing key because a third-party computer manufacturer or distributor shipped Ubuntu on a Restricted Boot machine.
"In such situations, the computer distributor - not Canonical or Ubuntu - would be the one responsible for providing the information necessary for users to run modified versions of the software," he said.
The FSF said it would continue its political campaign to make users aware of the problems associated with secure boot and also make available as much documentation as possible to enable users to understand how to run their own software on their own machines.