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Hypervisors Can Defeat GPLv3's Anti-Tivoization
DeviceGuru writes "A hypervisor can be used to isolate from each other software works released under incompatible licenses, while allowing them to run simultaneously on the same hardware. For example, Linux and Windows CE can run on separate virtual machines on one device, without violating either OS's license. Due to the isolation between multiple VMs running atop a hypervisor, it seems like this architecture could allow companies to build Linux-based devices, such as mobile phones or set-top boxes (think TiVo), that can't be upgraded by their users without authorization, thereby circumventing the GPLv3's 'anti-tivoization' clauses." Here's a white paper with more details from a commercial hypervisor company.
Frankly, I'm not sure what the article is trying to state.
If the code is released under GPLv3, then modifications of the code must be able to run on the same hardware. It doesn't matter if the key to run the code is a checksum or a password to give the hypervisor. Either way, if modification of the client cannot be dropped into the place of the original client (either to run on the same hardware or the same hypervisor), it's in abuse of the GPLv3.
Help! I'm a slashdot refugee.
the Anti-Tivoization clause is one the sore points in my book about the GPL 3. Because of the hippocraticy worded in it,
For TiVo being a consumer product is Bad, IBM Being corporate product it is good.
Free Software has a lot of advantages but if you try to get too academic with it it gets to a point where adoption of such products are impractical.
Take the TiVo, what GPLv3 wanted to do was force TiVo to release their DRM so the community has access to their product. What actually happends is TiVo
finds a backdoor to the license and uses it, or drops using open source and any stop to any shared contributions from TiVo and a move to a different
platform.
The License for free software is the cost of using the software. (Except for trading money (and rules) for rights to use, you agree to follow these rules for
rights to use) as more rules you add to the license the more expensive the free software becomes. So if you make FreeSoftware to strict on its use
people won't use it. Academically Free as in speech software sounds like a good plan but real life realizes there is information that you want to keep
private.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Simply put, if any part of the firmware is GPL 3'ed, even if it's running under a VM, it still requires the ability to replace it by the user w/o authorization from the factory. If I remember the license and discussion about it, it's "if it's in there, it's there for all."
--
# Canmephians for a better Linux Kernel
$Stalag99{"URL"}="http://stalag99.net";
To help slashdotters not have to RTFA!
(from the whitepaper link)
"Device vendors are also required to provide access to the source code of the GPL programs (see PLv2 ï½3, GPLv3 ï½6), including "the scripts used to control compilation and installation of the executable" [Footnotes 4, 6]. However, the GPLv2 does not require that installed executables must work, which enables a mechanism the Free Software Foundation calls "Tivoization."
"Tivoization," according to LinuxInfo.org, "refers to the configuring (by the manufacturer or vendor) of a digital electronic product that uses free software, so that the product will operate only with a specific version of such software." Technically, this means that a vendor of a product that uses GPL v2 programs could provide access to the source code, thus being compliant with the software license, but the product would be prevented from working if a modified version is installed, through the checking of the software image's signature."
The resulting product is fundamentally different from a TiVo.
While on TiVo, there is no way to change any part of the code without the signing key, in the proposed solution it is possible for the user to change the whole open-source system with an other one, as required by the GPLv3 license. As such, there is much more freedom for the user to tinker with its own system.
But for the manufacturer, it has the distinct advantages that some parts of the system can be isolated from the open subsystem, in a much more stable way, both legally and technically, than in a closed-source driver. Thus, it is possible to implement DRM, software subject to type conformance, or safety-critical tasks without risking corruption from the open system, whatever this system does. And contrary to the current solution, this does not require additional hardware.
Really, your new version of the kernel will have the same privileges as the old version. I see no problem with that.
I only fail to understand why they plan to put a kernel above that hypervisor. For it to be of any use, the hypervisor must controll all I/O operations anyway, what they get from Linux?
Rethinking email
I may be confused, but isn't this actually a way of complying with the GPL3? Using a hypervisor allows users to upgrade the kernel of their device without running into the (theoretical) security problems that companies who lock down their devices are afraid of.
They want it because the price is unbeatable. It's just that it has an annoying license that they have to work around, in order to be able to sufficiently hamstring their users.
See, that's never made much sense to me. Why don't they just pick up a gratis operating system with a more permissive license, like one of the BSD's, and stop worrying about tivoizing GPL'ed code?
Or are they actually just evil and want to lock down GPL'ed code because it fills their weekly evil quota or something?