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% Binary blob minimalisation policy % Leah Rowe % 4 January 2022 (updated 15 November 2022)
Introduction
In the beginning Libreboot intentionally de-blobbed coreboot, which is to say that it did not include binary blobs. Coreboot, on the other hand, requires binary blobs on most systems that it has support for. Libreboot's entirely "free" version of coreboot consequently supported fewer mainboards.
Libreboot's zero blobs policy has been scrapped, entirely. The goal of current libreboot is simply to support every single system from coreboot, to provide pre-configured, automated compiling of ROM images for all of them. This is quite a lot more ambitious in terms of sheer workload, and maintenance. It is expected that the project will grow in the future, to accomodate board maintainers, just like you have package maintainers in Debian; the analogy is highly appropriate, given the nature of the libreboot build system, which you can learn more about on the lbmk maintenance manual.
This policy change was implemented, by merging osboot with Libreboot. The osboot project was a fork of Libreboot lead by the same founder, Leah Rowe, and initially maintained in parallel with Libreboot. On November 15th, 2022, the two projects merged into a single project, continuing under the Libreboot banner. The osboot project existed between December 2020 (as retroboot, months later renamed to osboot) and November 2022; osboot has been assimilated by Libreboot!
Freedom is very much preferable and a world where everyone can use Free Software, exclusively, is to be welcomed. However, we do not yet live in that world.
The libreboot position is more like an opinion, as opposed to an actual policy. That opinion is this: some freedom is better than zero freedom. There are plenty of people with coreboot-compatible hardware, who wish to move away from otherwise fully proprietary boot firmware (usually supplied by the manufacturer of the hardware). The libreboot project is here to help! It provides a fully automated build system, making coreboot much easier to use, and it provides user-friendly installation guides to help you get started.
Supporting more hardware, even if the hardware is less friendly to software freedom, will provide a path towards coreboot for more people, and it may lead to more coreboot development in the future.
Freedom is still the ultimate goal, and coreboot provides a lot more freedom to the user compared to fully proprietary vendor firmware. Making coreboot easier to use is a noble goal, and the result is that more people can achieve a level of computing freedom that they would otherwise not have.
The following diagram shall set the tone for the rest of this article:
Current project scope
The libreboot project is concerned with what goes in the main boot flash IC, but there are other pieces of firmware to take into consideration, as covered in the libreboot FAQ.
Most critical of these are:
- Embedded controller firmware
- HDD/SSD firmware
- Intel Management Engine / AMD PSP firmware
Specific binary blobs are also problematic, on most coreboot systems, but they differ per machine.
For information about Intel Management Engine and AMD PSP, refer to the FAQ.
Blob minimalization policy
Default configurations
The libreboot project has the following policy:
- If a blob can be avoided, it should be avoided. For example, if VGA ROM
initialization otherwise does a better job but coreboot has free init code
for a given graphics device, that code should be used in libreboot, when
building a ROM image. Similarly, if memory controller initialization is
possible with a binary blob or free code in coreboot, the free code
should be used in ROMs built by
lbmk, and the blob for raminit should not be used; however, if no free init code is available for said raminit, it is permitted and lbmk will use the blob. - Some nuance is to be observed: on some laptop or desktop configurations, it's common that there will be two graphics devices (for example, an nvidia and an intel chip, using nvidia optimus technology, on a laptop). It may be that one of them has free init code in coreboot, but the other one does not. It's perfectly acceptable, and desirable, for libreboot to support both devices, and accomodate the required binary blob on the one that lacks native initialization.
- An exception is made for CPU microcode updates: they are permitted, and in fact required as per libreboot policy. These updates fix CPU bugs, including security bugs, and since the CPU already has non-free microcode burned into ROM anyway, the only choice is either x86 or broken x86. Thus, libreboot will only allow coreboot mainboard configurations where microcode updates are enabled, if available for the CPU on that mainboard.
- Intel Management Engine: in the libreboot documentation, words must be written
to tell people how to neuter the ME, if possible on a given board.
The
me_cleanerprogram is very useful, and provides a much more secure ME configuration. - Binary blobs should never be deleted, even if they are unused. In the
coreboot project, a set of
3rdpartysubmodules are available, with binary blobs for init tasks on many boards. These must all be included in libreboot releases, even if unused. That way, even iflbmkdoes not yet integrate support for a given board, someone who downloads libreboot can still make changes to their local version of the build system, if they wish, to provide a configuration for their hardware.
Generally speaking, common sense is applied. For example, an exception to the minimalization might be if blob raminit and free raminit are available, but the free one is so broken so as to be unusable. In that situation, the blob one should be used instead, because otherwise the user might switch back to an otherwise fully proprietary system, instead of using coreboot (via libreboot).
Configuration
The principles above should apply to default configurations. However, libreboot is to be configurable, allowing the user to do whatever they like.
It's natural that the user may want to create a setup that is less free than the default one in libreboot. This is perfectly acceptable; freedom is superior, and should be encouraged, but the user's freedom to choose should also be respected, and accomodated.
In other words, do not lecture the user. Just try to help them with their problem! The goal of the libreboot project is simply to make coreboot more accessible for otherwise non-technical users.
FREEDOM CATALOG
A blob status page should also be made available, educating people about the
status of binary blobs on each machine supported by lbmk.
It is desirable to see a world where all hardware and software is free. Hardware!?
Yes, hardware. RISC-V is a great example of a modern attempt at free hardware. It is a free ISA for the manufacture of a microprocessor. Many real-world implementations of it already exist, that can be used, and there will only be more.
Free hardware is still in its infancy. We should start a project that will catalog the status of various efforts, including at the hardware level (even the silicon level). Movements like OSHW and Right To Repair are extremely important, including to the Free Software movement which otherwise will typically think less about hardware freedom (even though it really, really should!)
One day, we will live in a world where anyone can get their own chips made, including CPUs but also every other type of IC. Efforts to make homemade chip fabrication a reality are now in their infancy, but such efforts do exist, for example, the work done by Sam Zeloof and the Libre Silicon project:
- https://www.youtube.com/channel/UC7E8-0Ou69hwScPW1_fQApA
- http://sam.zeloof.xyz/
- https://libresilicon.com/
(Sam literally makes CPUs in his garage)
Problems with RYF criteria
You can read those guidelines by following these hyperlinks:
The FSF RYF guidelines state the following:
- "However, there is one exception for secondary embedded processors. The exception applies to software delivered inside auxiliary and low-level processors and FPGAs, within which software installation is not intended after the user obtains the product. This can include, for instance, microcode inside a processor, firmware built into an I/O device, or the gate pattern of an FPGA. The software in such secondary processors does not count as product software."
This is a violation of every principle the FSF stands for, and it should be rejected on ideological grounds. The rest of libreboot's policy and overall ideology expressed, in this article, will be based largely on that rejection. The definition of product software is completely arbitrary; software is software, and software should always be free. Instead of making such exceptions, more hardware should be encouraged, with help given to provide as much freedom as possible, while providing education to users about any pitfalls they may encounter, and encourage freedom at all levels. When an organisation like the FSF makes such bold exceptions as above, it sends the wrong message, by telling people essentially to sweep these other problems under the rug, just because they involve software that happens to run on a "secondary processor". If the software is possible to update by the user, then it should be free, regardless of whether the manufacturer intended for it to be upgraded or not. Where it really isn't possible to update such software, proprietary or not, advice should be given to that effect. Education is important, and the FSF's criteria actively discourages such education; it creates a false hope that everything is great and wonderful, just because the software on one arbitrary level is all free.
This view of the FSF's, as expressed in the quoted paragraph, assumes that there is primarily one main processor controlling your system. On many modern computers, this is no longer true.
Free software does not exist in a vacuum, but we had less freedom in the past, especially when it came to hardware, so software was our primary focus.
The four freedoms are absolute, but there is a lot of nuance when it comes to boot firmware, nuance which is largely non-existent outside of firmware development, or kernel development. Most typical application/system software is high level and portable, but boot firmware has to be written for each specific machine, and due to the way hardware works, there are many trade-offs made, including by the FSF when defining what standards should apply in practise.
The fact that almost nobody talks about the EC firmware is because of the Respects Your Freedom certification. In reality, the EC firmware is crucial to user freedom, and ought to be free, but it is completely disregarded by the FSF as part of the hardware. This is wrong, and the FSF should actively actively encourage people to free it, on every laptop!
Other firmware currently outside the reach of the libreboot project are covered in the libreboot FAQ page. For example, HDD/SSD firmware is covered in the FAQ. Again, completely disregarded and shrugged off by the FSF.
The libreboot project will not hide or overlook these issues, because they are indeed critical, but again, currently outside the scope of what lbmk does. At the moment, lbmk concerns itself just with coreboot, but this ought to change in the future.
Examples of FSF sweeping blobs under the rug
Over the years, there have been numerous cases where the FSF actively fails to provide incentive for levels of software freedom, such as:
- TALOS II "OpenPOWER" workstation from Raptor Engineering USA. It contains a broadcom NIC inside it which requires firmware, and that firmware was non-free. The FSF were willing to ignore it, and certify the TALOS II product under RYF, but Timothy Pearson of Raptor Engineering had it freed anyway, without being told to. Hugo Landau reverse engineered the specification and Evan Lojewski wrote free firmware. See: See: https://www.devever.net/~hl/ortega and https://github.com/meklort/bcm5719-fw
- FSF once endorsed the ThinkPad X200, as sold by Minifree Ltd, which contains the Intel ME; the bootrom is still there, as is the ME coprocessor, but the ME is put into a disabled state via the Intel Flash Descriptor, and the ME firmware in flash is removed. However, the ME is an entire coprocessor which, with free firmware, could be used for a great many things. In the Libreboot and coreboot projects, there has always been interest in this but the FSF disregards it entirely. The X200 product they certified came with Libreboot pre-installed.
- Libreboot has a utility written by I, Leah Rowe, that generates ICH9M flash descriptors and GbE NVM images from scratch. This is necessary to configure the machine, but these are binary blobs otherwise; the FSF would have been quite content to certify the hardware anyway since these were non-software blobs in a format fully documented by Intel (they are just binary configuration files), but I went ahead and wrote ich9gen anyway. With ich9gen, you can more easily modify the descriptor/gbe regions for your firmware image. See: https://libreboot.org/docs/install/ich9utils.html - libreboot also has this
- FSF once endorsed the ThinkPad T400 with Libreboot, as sold by Minifree. This machine comes in two versions: with ATI+Intel GPU, or only Intel GPU. If ATI GPU, it's possible to configure the machine so that either GPU is used. If the ATI GPU is to be used, a firmware blob is needed for initialization, though the driver for it is completely free. FSF ignored this fact and endorsed the hardware, so long as Libreboot does not enable the ATI GPU or tell people how to enable it. The Intel GPU on that machine has free initialization code by the coreboot project, and a fully free driver in both Linux and BSD kernels. In the configuration provided by Libreboot, the ATI GPU is completely disabled and powered down.
- All Libreboot-compatible ThinkPads contain non-free Embedded Controller firmware, which is user-flashable (and intended for update by the manufacturer). The FSF chose to ignore the EC firmware, under their secondary processor exemption. See: http://libreboot.org/faq.html#ec-embedded-controller-firmware
In all of the above cases, the FSF could have been stricter, and bolder, by insisting that these additional problems for freedom were solved. They did not. There are many other examples of this, but the purpose of this article is not to list all of them (otherwise, a book could be written on the subject).
Problems with FSDG
The FSDG criteria is separate from RYF, but has similar problems. FSDG is what the FSF-endorsed GNU+Linux distros comply with. Thoughts:
- Excluding firmware blobs in the linux kernel is bad. Non-free firmware is also bad. Including them is a wiser choice, if strong education is also provided about why they are bad (lack of freedom). If you expose them to the user, and tell them about it, there is greater incentive (by simple reminder of their existence) to reverse engineer and replace them.
- Firmware in your OS kernel is good. The FSF simultaneously gives the OK for hardware with those same firmware blobs if the firmware is embedded into a ROM/flash chip on the device, or embedded in some processor. If the firmware is on separate ROM/flash, it could still be replaced by the user via reverse engineering, but then you would probably have to do some soldering (replace the chip on the card/device). If the firmware is loaded by the OS kernel, then the firmware is exposed to the user and it can be more easily replaced. FSF criteria in this regard encourages hardware designers to hide the firmware instead, making actual freedom less likely!
Besides this, FSDG seems OK. Any free operating system should ideally not have non-free drivers or applications.
Hardware manufacturers like to shove everything into firmware because their product is often poorly designed, so they later want to provide workarounds in firmware to fix issues. In many cases, a device will already have firmware on it but require an update supplied to it by your OS kernel.
The most common example of non-free firmware in Linux is for wifi devices. This is an interesting use-case scenario, if freed, because it could be used for owner-controlled software defined radio.
The Debian way is ideal. The Debian GNU+Linux distribution is entirely free by default, and they include extra firmware if needed, which they have in a separate repository containing it. If you only want firmware, it is trivial to get installer images with it included, or add that to your installed system. They tell you how to do it, which means that they are helping people to get some freedom rather than none. This is an inherently pragmatic way to do things, and it's now how Libreboot does it.
OpenBSD is very much the same, but they go a step further: during the initial
boot, after installation, it tells you exactly what firmware is needed and
updates that for you. It's handled in a very transparent way, by
their fw_update program which you can read about here:
https://man.openbsd.org/fw_update
Banning linux-firmware specifically is a threat to freedom in the long term, because new users of GNU+Linux might be discouraged from using the OS if their hardware doesn't work. You might say: just buy new hardware! This is often not possible for users, and the user might not have the skill to reverse engineer it either.
More detailed insight about microcode
To be clear: it is preferable that microcode be free. The microcode on Intel and AMD systems are non-free. Facts and feelings rarely coincide; the purpose of this section is to spread facts.
The libreboot build system now enables microcode updates by default.
Not including CPU microcode updates is an absolute disaster for system stability and security.
Making matters worse, that very same text quoted from the FSF RYF criteria in fact specifically mentions microcode. Quoted again for posterity:
"However, there is one exception for secondary embedded processors. The exception applies to software delivered inside auxiliary and low-level processors and FPGAs, within which software installation is not intended after the user obtains the product. This can include, for instance, microcode inside a processor, firmware built into an I/O device, or the gate pattern of an FPGA. The software in such secondary processors does not count as product software."
Here, it is discussing the microcode that is burned into mask ROM on the CPU itself. It is simultaneously not giving the OK for microcode updates supplied by either coreboot or the Linux kernel; according to the FSF, these are an attack on your freedom, but the older, buggier microcode burned into ROM is OK. This is absolutely inconsistent.
The CPU already has microcode burned into mask ROM. The microcode configures logic gates in the CPU, to implement an instruction set, via special decoders which are fixed-function; it is not possible, for example, to implement a RISCV ISA on an otherwise x86 processor. It is only possible for the microcode to implement x86, or broken x86, and the default microcode is almost always broken x86 on Intel/AMD CPUs; it is inevitable, due to the complexity of these processors.
The basis of the FSF's disagreement about microcode updates is that they do believe otherwise; Stallman himself expressed such ignorance to me, in an email conversation that I had with him as of January 2nd, 2022. The FSF believes that these x86 microcode updates (on Intel/AMD) allow you to completely create a new CPU that is fundamentally different than x86. This is not true. It is also not true that all instructions in x86 ISA are implemented with microcode. In some cases, hardcoded circuitry is used! The microcode updates are more like tiny one liner patches here and there in a git repository, by way of analogy. To once again get in the head-space of the FSF: these updates cannot do the CPU equivalent of re-factoring an entire codebase. They are hot fixes, nothing more!
Not including these updates will result in an unstable/undefined state. Intel themselves define which bugs affect which CPUs, and they define workarounds, or provide fixes in microcode. Based on this, software such as the Linux kernel can work around those bugs/quirks. Also, upstream versions of the Linux kernel can update the microcode at boot time (however, it is recommend still to do it from coreboot, for more stable memory controller initialization or “raminit”). Similar can be said about AMD CPUs.
Here are some examples of where lack of microcode updates affected Libreboot, forcing Libreboot to work around changes made upstream in coreboot, changes that were good and made coreboot behave in a more standards-compliant manner as per Intel specifications. Libreboot had to break coreboot to retain certain other functionalities, on some GM45/ICH9M thinkpads:
These patches revert bug fixes in coreboot, fixes that happen to break other functionality but only when microcode updates are excluded. The most technically correct solution is to not apply the above patches, and instead supply microcode updates!
Pick your poison. Not adding the updates is irresponsible, and ultimately futile, because you still end up with non-free microcode anyway, just you get an older, buggier version instead!
The libreboot build system no longer applies the two patches linked above! Instead, CPU microcode updates are enabled by default, on the affected boards. The result is superior IA32 feature control and added PECI support.
The libreboot project rejects the FSF's narrow, dogmatic view entirely.
This shift in project policy does not affect your freedom at all, because you still otherwise have older, buggier microcode anyway. However, it does improve system reliability by including the updates!
Such pragmatic policy is superior to the dogma that Libreboot users once had to endure. Simply put, the Libreboot project aims to give users as much freedom as is possible for their hardware; this was always the case, but this mentality is now applied to [a lot] more hardware.
Other considerations
Also not covered strictly by Libreboot: OSHW and Right To Repair. Freedom at the silicon level would however be amazing, and efforts already exist; for example, look at the RISCV ISA (in practise, actual fabrication is still proprietary and not under your control, but RISCV is a completely free CPU design that companies can use, instead of having to use proprietary ARM/x86 and so on). Similarly, Right To Repair (ability to repair your own device, which implies free access to schematics and diagrams) is critical, for the same reason that Free Software (Right To Hack) is critical!
OSHW and Right To Repair are not covered at all by RYF (FSF's Respects Your Freedom criteria), the criteria which Libreboot was created to comply with. RYF also makes several concessions that are ultimately damaging, such as the software as circuitry policy which is, frankly, nonsensical. ROM is still software. There was a time when the FSF didn't consider BIOS software a freedom issue, just because it was burned onto a mask ROM instead of flashed; those FSF policies ignore the fact that, with adequate soldering skills, it is trivial to replace stand-alone mask ROM ICs with compatible flash memory.
Conclusion
Compromise and nuance is the name of the game, even if you're the FSF. It is completely unavoidable, but there are some who try to deny this fact and pretend like things are as they'd prefer them to be, rather than how they actually are in the real world.
Facts and feelings are usually very different things, and contradictory.
RYF isn't wrong per se, just flawed. It is correct in some ways and if complied with, the result does give many freedoms to the user, but RYF completely disregards many things that are now possible, including freedoms at the hardware level (the RYF criteria only covers software). Those guidelines are written with assumptions that were still true in the 1990s, but the world has since evolved. As of 2 January 2022, Libreboot still complies strictly with RYF, and will continue to do so, at least for the time being. The libreboot project rejects those policies in their entirety, and instead takes a pragmatic approach.
The conclusion that should be drawn from all of this is as follows:
Following FSF criteria does not damage anything, but that criteria is very conservative. Its exemptions should be disregarded and entirely ignored. RYF is no longer fit for purpose, and should be rewritten to create a more strict set of guidelines, without all the loopholes or exemptions. As has always been the case, Libreboot tries to always go above and beyond, but the Libreboot project does not see RYF as a gold standard. There are levels of freedom possible now that the RYF guidelines do not cover at all, and in some cases even actively discourage/dis-incentivize because it makes compromises based on assumptions that are no longer true.
Sad truth: RYF actively encourages less freedom, by not being bold enough. It sets a victory flag and says mission accomplished, despite the fact that the work is far from complete!
If followed with exemptions unchallenged, RYF may in some cases encourage companies to sweep under the rug any freedom issues that exist, where it concerns non-free firmware not running on the host CPU (such as the Embedded Controller firmware).
I propose that new guidelines be written, to replace RYF. These new guidelines will do away with all exemptions/loopholes, and demand that all software be free on the machine, or as much as possible. Instead of only promoting products that meet some arbitrary standard, simply catalog all systems on a grand database of sorts (like h-node.org, but better). Include Right to Repair and OSHW (including things like RISCV) in the most "ideal" standard machine.
Don't call it "Respects Your Freedom" or something similar. Instead, call it something like: the freedom catalog. And actually focus on hardware, not just software!
In the year 2022 onwards, we can do better. The RYF program should be cancelled. It is no longer fit for purpose.
Other resources
Ariadne Conill's RYF blog post
Ariadne Conill, security team chair of Alpine Linux, posted a very robust article about RYF, with similar points made when compared to this article. However, Ariadne goes into detail on several other examples of problems with the FSF RYF criteria; for example, it talks about the Novena product by Bunnie.
It's worth a read! Link:
Hector Martin's RYF thread
Hector Martin, leader of the Asahi Linux project (for booting linux kernels on M1 macbooks) wrote a very robust twitter thread criticizing the RYF criteria and much of what he wrote inspired this article that you are reading. See:
https://twitter.com/marcan42/status/1040626210999431168
If you wish to avoid non-free javascript, you can read this thread using nitter:
https://nitter.net/marcan42/status/1040626210999431168
Article updates
23 January 2022
Added link to Ariadne Conill's article.
21 January 2022
This article was updated on 21 January 2022, to add the section with examples in the real world of FSF sweeping blobs under the rug (ATI T400 thinkpads, ICH9M descriptors and TALOS II NIC firmware).
Also on 21 January 2022: added section about FSDG (criticisms of it).
Also on 21 January 2022: added link to Hector Martin's twitter thread.