I'm a strong advocate of open source who also happens to agree with microsoft's lawyers on this. Whether you believe this consequence of GPLv3 is intentional or unintentional, it is a consequence. The idea of somehow putting blame back on Microsoft for this is similarly twisted.

Vendors shipping absolute shit implementation of SecureBoot that don't give the users authority over their own systems are the problem.

Let's revisit this topic in the future to see how many systems actually get patched to revoke these signatures. My guess is that nearly 100% of shipping systems 1 year from now will still have these keys and still boot these vulnerable signed binaries right out of the box.

One might hope that this issue thrusts the theater of Secure Boot into the public discourse, but like most other forms of irrelevant DRM, it will simply remain a hurdle that everyone has to keep jumping over until the end of time.

> Vendors shipping absolute shit implementation of SecureBoot that don't give the users authority over their own systems are the problem.

Microsoft itself has been the _first_ vendor who shipped systems where SecureBoot could neither be disabled nor the whitelist of signatures/keys replaced with your own. This would be _the only_ scenario where the GPLv3 would have anything to say ... if Microsoft were to be also shipping GRUB in that system, which they weren't .

And such scenario is precisely one of those the GPLv3 was designed to impede. So it is most definitely intentional.

There is no one to blame other than Microsoft.

> Microsoft itself has been the _first_ vendor who shipped systems where SecureBoot could neither be disabled nor the whitelist of signatures/keys replaced with your own.

It’s misleading to mention that but not say that you’re referring to Surface RT tablets, which were Microsoft’s equivalent of an iPad ecosystem — only Store apps, OEM OS only, etc. It’s also running a different flavor of Windows on an ARM processor.

Surface Pro devices have always had toggleable & configurable Secure Boot.

Why misleading? It shows exactly what the long-term MS strategy was, what SecureBoot was designed for, and it also shows exactly who shipped the first "shitty" SecureBoot implementation. People had to resort to cracks in order to run plain Win32 apps! Except, of course, Office. That one is the only Win32 app which was allowed. Good ol', classy Microsoft.

> Surface Pro devices have always had toggleable & configurable Secure Boot.

Not at all. While it is true that Secure Boot has been deactivable in the "Pro" family, disabling Secure Boot results in Scary Boot Prompts (TM) (a _permanent_, literal red screen warning during the boot process that would drive most users away). _To this day_, there is no way to install your own Secure Boot keys in the Surface UEFI setup. Again, one of the "shitty" implementations, and comes from Microsoft!

It's actually worse than that. At least the first two Surface Pro iterations didn't even ship with the UEFI CA key, meaning you could not even install MS-signed Linux distros! The only way would be to disable Secure Boot, and thus have to suffer the red Scary Boot Prompts (TM) on every boot prompt. Again, MS leading the way for the other OEMs in terms of shittiness.

Almost two years afterwards, MS started shipping a WMI-based method that would allow you to install the MS UEFI CA. So you had to install Windows and run a Windows program in order to be able to install an OS signed with your own keys. This is _still true_ even in the latest iteration of Surface Pro devices. This is the example that MS sets for other OEMs.

And almost 10 years later, Lenovo starts disabling the UEFI MS CA key by default....

Wouldn't it be the same scenario as if I sign a release binary with a GPG key, or even sign a commit with GPL code with a GPG key?

I don't get what is different between signing workflows that OSS has used for decades and this?

The difference starts when the _right_ signature is required to continue using the software, preventing you from effectively modifying the software.

Couldn't they release a signature separate from the thing they signed? Leaving it as work that the open source world has to do to combine them into the derivative work? Surely an attestation/signature would be a fair use derivative work?

Would it?

Suppose I write some GPLv3 code. You incorporate that code into a program called shim-gpl3 and release the result under the GPLv3. You also release a binary. Microsoft signs that binary and releases the signature but does not redistribute the binary. Microsoft says that they don’t think that the signature is a copyrightable work but that, to the extent that it is, it is permissively licensed (CC0, MIT, whatever). A Linux distribution builds an installer that contains, shim-gpl3 and Microsoft’s signature. The recipient of the distribution asks the distributor for source to the GPL v3 parts of their distro.

The problem (as I see it) is that the distributor cannot comply. This is as intended! The media, as is, runs on an effectively TiVo-ized machine, and neither the distributor nor the end-user can build it from source such that the result works if modifications are applied.

If I publicly attest to something, and provide cryptographic proof that you can verify the version you are looking at is the one that I attest to, then I do not see how that is meaningfully a derivative work of what we are attesting. It is not substantial enough in size or form for it to be a derivative work. So, from that end, it seems we agree that the signature itself is not a problem.

Now, it seems what you are implying is that they need a new signature that must be created at build time. I'm asking for a much more restrictive bootloader that would have to be buildable with a repeatable process so that someone else can create the same one down to the bit level. Is this as useful as one that is not as restricted? No, but it would be a way past the legal problem?

> I'm asking for a much more restrictive bootloader that would have to be buildable with a repeatable process so that someone else can create the same one down to the bit level.

Reproducible builds are fantastic. But I doubt that, in this instance, it would be a valid way around the GPL.

Maybe if one, as an art project, made a project that, when compiled, had a particularly aesthetically pleasing binary representation, it would be okay. But we’re talking specifically about a signature needed to run the software, which appears to fit the definition of “Installation Information” in section 6 of the GPLv3.

My point is the signature can be combined after the fact. Basically, I can give you a binary that is the signature for another binary that is the boot loader, built to certain specifications. You build that, and combine with this signature, and you are good to go. If the build doesn't build exactly the same, signature will be invalid and you can't use it.

Note that this is VERY limited in how much it could possibly help. But I don't see why it wouldn't be permissible by all licenses involved. It doesn't require the signing key, but a valid signature. For that device, it is locked down enough that the only installer that can work is the one that matches this signature. If installing somewhere else, you don't need the signature anymore, and can make your own or use an unsigned loader.

You seem to still have an impression that “secure” here is somehow related to “security” of the users or their “authority over their own systems”, when in fact it only means “securing” the position of the company that gets to control the thing. Even if Microsoft fires everyone tomorrow and closes, Secure Boot key infrastructure and agreements will still cost a lot. Just like patent pools of former industrial giants that don't just disappear.

In the same manner, insane DRM schemes are not made to be solid and unbreakable, or because sellers are worried about home copies (made by people who won't buy the product anyway otherwise). DRM is just a convoluted enough mesaure to protect corporations from their fellow corporations who would gladly make the same thing, but more convenient, or cheaper, or more profitable, and ride the “piracy” wave. In the same manner, Google didn't shove HTTPS into everything because it was worried about the users, but because it was worried about other companies with massive traffic spying abilities grabbing the data Google collected for itself. Et cetera, et cetera.

Even on Azure, GNU/Linux runs on top of Windows based hypervisor (Cloud Host[0]), and WSL is a VM anyway.

Thus from Microsoft's point of view all is well.

[0] - https://techcommunity.microsoft.com/t5/windows-os-platform-b...

> The idea of somehow putting blame back on Microsoft for this is similarly twisted.

Microsoft are responsible for pushing secure boot on PCs in the first place. They are absolutely to blame for all problems it causes for regular users that did not explicitly seek a computer with secure boot.

> Vendors shipping absolute shit implementation of SecureBoot that don't give the users authority over their own systems are the problem.

How convenient for Microsoft.

If this were true, it probably applies to both GPLv2 and v3, since they both require installation instructions.

v3 adds an additional requirement that if you mere-aggregate GPL software and other software, and put the aggregate into a consumer product, you can't disable the other software because the GPL software was modified. I don't believe this would apply in the situation that these shims are intended for - i.e. installing an OS onto a desktop machine, as those are supposed to allow you to enroll new Secure Boot keys anyway.

I also don't understand why a signature from Microsoft would actually trip any of the above-mentioned requirements. Microsoft is not distributing the software, they're just signing it - i.e. distributing a message saying "this shim with this hash can run". That's not a copyright violation, so the GPL doesn't come into play at all.

Perhaps there's something else Microsoft does with their signatures that might trip GPL...

Maybe Microsoft just doesn’t want to sign a GPL bootloader and so they had their lawyers come up with nebulous concerns as a fig leaf. Microsoft <3 Open Source after all, can’t be seen as reluctant for business reasons.

To my knowledge, they aren't the ones signing the software. Microsoft runs a UEFI CA and just bless the developer's sub-CA. The developer is fully in control of their own CA and could sign whatever they want.

No. I don't know if Microsoft "partners" have some special privilege, but for 3rd parties Microsoft will _never_ sign your CA. They sign individual binaries.

I wonder if this is a consequence of the judicial system in the US. In Europe there is something called promesse de porte-fort (contract at the expense of third parties) as Microsoft is not party in the licence agreement I would say. Some effects of the GPL ( or rather interpretations) are just plain ineffective. I say this while not questioning the copy left in general.

Note that under no circumstances can it "compel" you to hand over the signing keys. It can compel you to _stop infringing_, though. Which you may do by either stop redistributing GRUB , or by allowing your customers to install their own signatures, or if you are really stupid, by giving out your private keys. But you cannot be forced to do the later.

As usual it's just FUD.

> FYI the reason is that the GPL would require you to hand over the signing keys. If you sign a GPLv3 licensed bootloader like GRUB, you're forced to also make public the signing key... which defeats the purpose.

That seems to be a ridiculous interpretation of the GPL (no personal offense meant, I'm sure you're a fine person but this idea is genuinely very silly).

Signatures on binaries are not part of the source code, and therefore the GPL isn't concerned with them.

Think of:

- every signed binary for an open source app on a Linux distro or Windows install

- Every open source web app delivered over a TLS cert

Nobody has ever considered that the private keys used to sign the package, executable or web site cert to be required by the GPL.

>are not part of the source code, and therefore the GPL isn't concerned with them.

IIRC the GPL concerns itself with buildscripts etc. and GPLv3 was written with the tivoization of v2 in mind.

https://www.gnu.org/licenses/quick-guide-gplv3.html

>Protecting Your Right to Tinker

>Tivoization is a dangerous attempt to curtail users' freedom: the right to modify your software will become meaningless if none of your computers let you do it. GPLv3 stops tivoization by requiring the distributor to provide you with whatever information or data is necessary to install modified software on the device. This may be as simple as a set of instructions, or it may include special data such as cryptographic keys or information about how to bypass an integrity check in the hardware. It will depend on how the hardware was designed—but no matter what information you need, you must be able to get it.

>This requirement is limited in scope. Distributors are still allowed to use cryptographic keys for any purpose, and they'll only be required to disclose a key if you need it to modify GPLed software on the device they gave you.

> Code submitted for UEFI signing must not be subject to GPLv3 or any license that purports to give someone the right to demand authorization keys to be able to install modified forms of the code on a device. Code that is subject to such a license that has already been signed might have that signature revoked. For example, GRUB 2 is licensed under GPLv3 and will not be signed.

It does according to MSFT lawyers: https://techcommunity.microsoft.com/t5/hardware-dev-center/u...

> any license that purports to give someone the right to demand authorization keys to be able to install modified forms of the code on a device

There's nowhere in the GPLv3 that says that (then again, that sentence doesn't imply there is). Anyone can download and modify the grub source code, and compile it. It doesn't mean Microsoft is obliged to sign their fork. I wonder if there's something that confused (or was bad faith interpreted) by Microsoft's lawyers?

Maybe someone can just use another open source license? Ie, anything not called 'GPLv3' which, like every other OSS license, does not purport to give someone the right to demand authorization keys to be able to install modified forms of the code on a device.

> There's nowhere in the GPLv3 that says that (then again, that sentence doesn't imply there is)

It does, commonly called the anti-tivoization clause. Here's the text:

> “Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.

> If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).

> The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.

> Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.

From GPLv3, section 6. Conveying Non-Source Forms.

> [...] any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work [...]

From what I understand, allowing the user to install their own trusted keys is enough; there's no need to allow users to sign with the "official" trusted key as long as that alternative exists.

I suspect that Microsoft's worry is that they don't control the firmware (the motherboard manufacturers do), and some UEFI firmware might be broken and not allow installing alternative trusted keys. I believe shim solves this by adding an intermediate layer which also allows the user to manually install their own trusted keys, even if the firmware doesn't.

You're correct. See my response to the other poster. https://news.ycombinator.com/item?id=39133890

They're probably referring to this part of the GPLv3 license:

> “Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.

> If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).

I believe the MSFT lawyers are right here, but obviously I'm not a lawyer.

Thanks! I was looking for the word 'sign' and couldn't find it.

I now think I was wrong earlier.

Summarizing https://www.gnu.org/licenses/gpl-3.0.html:

> The information (ie 'methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work') must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.

The purpose of allowing signing is exactly to ensure modified code does not function in that environment.

Yes MS (and you) would be right. GPLv2, BSD or MIT would be fine but GPLv3 would not.

-----------------------------------

Edit reply to baobun (rate limit means I can't post)

I did think about that, but:

> continued functioning of the modified object code

is vague. Does it mean a new firmware binary should continue working on the same device as the unmodified predecessor or using is a new device (that allows arbitrary entities to sign) considered to be "continued functioning"?

Not exactly. AshamedCaptain gets it. If the device can be configured to trust a user-supplied key instead of or in addition to Microsoft's, there is no need to provide any keys. This is up to the hardware supplier.

https://news.ycombinator.com/item?id=39134059

https://news.ycombinator.com/item?id=39133999

I did reply to this, but had to reply in my existing comment above due to the rate limit.

Actually, if you ask the Software Freedom Conservancy, not only is this a requirement of the GPLv3, it is in fact also required by the GPLv2 [0]:

> GPLv2 assures, to the purchaser of an embedded product, their absolute right to receive the information necessary to install a modified version of the GPLv2'd works. [...] installation of the GPL'd works must succeed and operate in a useful and functional fashion on the device.

I believe the FSF position is different, but it's unclear. At least one member of the SFC who was a member of the FSF in the past (Bradley Kuhn) [1] believes that the FSF has the same position - that both GPLv2 software and GPLv3 software must be accompanied by full instructions (and ability) for a user to install their own modified versions on any hardware containing this software. He believes that the only difference with GPLv3 is that, in addition to this requirement, other proprietary software on the device must continue to operate just as before; whereas, with the GPLv2, it's fine for other proprietary software to say "you're running an unsigned version of Linux, failing to start". Linus Torvalds' public statements about the GPLv3, as well as the FSF page on Tivoization [2], seem to suggest otherwise.

Either way, this is not some invention of MS lawyers meant to make the GPL look scarier, it is very much how the free software community sees the GPL working.

[0] https://sfconservancy.org/blog/2021/mar/25/install-gplv2/

[1] https://sfconservancy.org/blog/2021/jul/23/tivoization-and-t...

[2] https://www.gnu.org/philosophy/tivoization.en.html

So... really no. The overall spirit of the GPLv3 text is that the license demands preservation of the ability of an end user to modify and run the software they receive, see all the discussion at the time it was being drafted about "TiVoization". It does not specifically speak to encryption and signatures being used by the loader environment, but it's absolutely reasonable to interpret it that way.

If I buy a laptop from Lenovo, and it uses a signed GPLv3 bootloader, and I want to modify and run a new version of that bootloader, I'm prevented by the lack of a signature. That action is exactly what the license demands Lenovo permit.

Now, obviously this collides badly with the security requirements of the system. So it's likewise totally reasonable to imagine a court flipping the other way and refusing to literally enforce the GPLv3 because of the potential damage to the market. But if that happens, then what gives Lenovo any right to ship that GPLv3 software at all? Now they're subject to the bootloader authors demanding they stop shipment of the infringing product.

No, the permissively-licensed shim compromise was the right choice.

> No, the permissively-licensed shim compromise was the right choice.

Why? Why on earth?

IF Lenovo wanted to really ship a GPLv3 bootloader, all it imposes on Lenovo is they ship a method to install your own bootloader keys. Do you really disagree with that?

Lenovo has already shipped hardware which requires magical incantations to install anything other than Windows (see Secured Core hardware). Why on earth anyone shipping FLOSS software would drop their pants to allow precisely this shitshow is over me.

I'm not the person you should be arguing with. I didn't write the license and I'm not the judge that would have to make the decision. I was explaining why the collision between software freedom and end user security requirements (which is a very real thing!) is seen as a risk to the people shipping and supporting actual hardware.

There is no collision _whatsoever_ between software freedom and security requirements. It's an illusion which happens to be highly convenient to those who want to promote an artificially controlled market and sell that as snake-oil security.