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Is Linksys Violating The GPL?
jap writes "According to this post on LKML, Linksys is shipping firmware for (at least their) 802.11g access-points based on Linux - without any sourcecode available or mentioning of it on their site. This could be interesting: it might provide the possibility of building an ueber-cool accesspoint firmware with IPsec and native ipv6 support etc etc, using this information!"
If you push too hard for publishing source code, this box will be running Cisco IOS soon, slowing down the box 4 fold.
Sorry - not true.
http://www.tivo.com/linux/index.html
Hi,
Sorry for the very lengthly posting, but I want to be as precise as possible in describing this problem.
Awhile ago, I mentioned that the Linksys WRT54G wireless access point used several GPL projects in its firmware, but did not seem to have any of the
source available, or acknowledge the use of the GPLed software. Four weeks ago, I spoke with an employee at Linksys who confirmed that the system did use Linux, and also mentioned that he would work with his management to ensure that the source was released. Unfortunately, my e-mails to this
individual over the past three weeks have gone unanswered. Of course, I also tried contacting Linksys through their common public e-mail accounts (, ) to no avail.
However, it is hard for me to know if my contact in the company has just gone on a three week vacation (and not set an auto-responder), or has been asked to not answer anymore mail on this subject. Also, I should note that I don't own this product, so I can't determine if the source is shipped with it.
However, I have gone through all the available information on the Linksys website, and can find no reference to the GPL, Linux (as it relates to this product), or the firmware source code. Also, the firmware binary (see below) is freely available from their website. There is no link from the download page to the source, or any mention of Linux or the GPL. Finally, it would be
strange if the source was included in the physical package, as my contact at Linksys was initially unaware Linux was used in this product.
The following steps can be used to determine the exact nature of the possible GPL violation.
1. Go to the following URL:
http://www.linksys.com/download/firmware.asp?fwid= 178
2. Download the "firmware upgrade files":
ftp://ftp.linksys.com/pub/network/WRT54G_ 1.02.1_US _code.bin
(MD5SUM: b54475a81bc18462d3754f96c9c7cc0f)
3. While it is downloading, confirm that there is nothing on the webpage to indicate that this binary contains GPLed software.
4. Once the download is complete, copy the contents of the file from offset 0xC0020 onward into a new file.
dd if=WRT54G_1.02.1_US_code.bin of=test.dump skip=24577c bs=32c
5. Notice that this file is an image of a CramFS filesystem. Mount it.
6. Explore the filesystem. You will notice that the system appears to be based on Linux 2.4.5. Incidentally, there is at least one other GPLed project in the firmware: the BusyBox userland component: (http://www.busybox.net/)
7. The Linux kernel (I think) is mixed up with a bunch of other stuff in: bin/boot.bin
You might want to know why I am interested in getting the code for the kernel used in this device.
There's been some discussion here about Linux's lack of wireless support for a few of the newer 802.11b and (nearly?) all 802.11g chips. Incidentally, Linux has excellent support for at least one manufacturer's wireless family.
The following Broadcom chips all appear to be supported under Linux -- if you happen to be running Linux on a MIPS processor in a Linksys router:
Broadcom BCM4301 Wireless 802.11b Controller
Broadcom BCM4307 Wireless 802.11b Controller
Broadcom BCM4309 Wireless 802.11a Controller
Broadcom BCM4309 Wireless 802.11b Controller
Broadcom BCM4309 Wireless 802.11 Multiband Controller
Broadcom BCM4310 Wireless 802.11b Controller
Broadcom BCM4306 Wireless 802.11b/g Controller
Broadcom BCM4306 Wireless 802.11a Controller
Broadcom BCM4306 Wireless 802.11 Multiband Controller
This list was produced by running strings on:
lib/modules/2.4.5/kernel/drivers/net/wl/wl.o
I am trying to determine exactly how tightly coupled these drivers are to the kernel.
As an aside, I know that some wireless companies have been hesitant of releasing open source drivers because they are worried their radios might be pushed out of spec. However, if the drivers are alre
If they're not rewriting the source code, using it in a form that they themselves obtained it in (pre-compiling), they might not have to provide source if they disclose their source location. Also, if they were smart enough to create independent kernel modules for the rest of the device, they wouldn't have to release those anyway.
It would be nice if they included at least a copy of the GPL and a linux installation CD in the back of their manual though, since that would be a way of distributing the code, if not more than the code, and would probably make them in compliance.
Hell, TurboLinux install CDs came with hardware that Linux couldn't even use, for a while...
Do not look into laser with remaining eye.
A couple follow ups on the kernel mailing list:
A very interesting bit from the busybox maintainer, who has evidently already sent linksys two letters
A post outlinging the possibility that Belkin is also shipping GPL'd code
A few other people are throwing their two cents in, but those were the most interesting, code be an interesting test of corporate policey, and the ability of the GPL to withstand a court battle.
Not at all -- it just gives SCO another company to sue!
Why does everyone always assume that any embedded device running Linux must have, in some way, violated the GPL?
I worked eight years as a firmware engineer. In the last three, I dealt almost exclusively with Linux.
And I can assure you that we didn't need to change any GPL'd code to get what we wanted. Even on fairly custom hardware, we could find preexisting GPL'd code to do 99% of what we needed (and wrote user-space drivers where possible, and modules where not). No need to release anything if you don't change anything, to comply with the GPL.
Whether ethical or not, plenty of legal ways of circumventing the intent of the GPL exist. And, like it or not, eliminating those loopholes (which would basically require forcing any program that runs under linux to use the GPL) would kill Linux in the business world.
The GPL has no real valid legal meaning until it has been tested in a court of law. I think the fact that no GPL violation case has ever made it into a courtroom speaks volumes!
Yes it does. It means that until now noone has had the guts to risk a legal confrontation to free themselves from the requirements the GPL imposes.
And even if the GPL has no valid legal meaning, what remains? Standard copyright law. So without the GPL you don't even have the right to download the source, let alone modify and republish it!
And I'm sure you know this, but they are not required to release all of their source code, only the code for gpl parts of tivo. Just because the OS is linux doesn't mean they have to release code for everything running on it.
Two points. I always have two points.
First, as someone else already said, just becuase it uses a linux kernel doesn't mean they modified anything, it could be a stock kernel. If they wrote userspace drivers and/or kernel modules using existing interfaces for their custom hardware, they are not obligated to release anything.
Secondly, if they weren't abiding by terms they had to according to the GPL, it would be COPYRIGHT violation, not license violation, as if you don't comply with the license, copyright law says they can't redistribute it. I know it seems like a silly point, but it's not.
People talk about the GPL being "tested in court" and whatnot.. but the fact is: If you don't accept the GPL as valid, then copyright law still stands, and says you can't redistribute, or make derivitive works. A judge can rule the GPL as invalid, but that would mean that nobody had any rights to redistribute anything.
It's not a license you had to accept and agree to in order to use the product.. so you can't "violate" it.
Linus, or any other kernel developer could go to linksys, and say "I have not granted you permission to use my copyrighted work, please demonstrate why you think you are allowed to do this". They can then either cite how the GPL allows them to do what they do, or concede that they have no right to distribute.
So as unclear as I can be.. it's not a GPL violation... and people are not forced to release code because of a nonexistant GPL violation... although that might be an acceptable remedy to all parties in most cases. They could also be forced to simply stop doing it.
However, the GPL still requires that they provide source, even if they have not modified it. If you redistribute, you must provide source, or at least a written offer for the source.
.. they are obligated to provide a copy of the source (sans their changes, if they are not within the scope of the gpl)
You can (section c) simply pass along the written offer YOU received, if you are simply redistributing, and not modifying, but only if it's NON-COMMERCIAL, and only if you yourself received the written offer. IF they are using stock linux kernels, there is no written offer, so
3. You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following:
* a) Accompany it with the complete corresponding machine-readable source code, which must be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,
* b) Accompany it with a written offer, valid for at least three years, to give any third party, for a charge no more than your cost of physically performing source distribution, a complete machine-readable copy of the corresponding source code, to be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,
* c) Accompany it with the information you received as to the offer to distribute corresponding source code. (This alternative is allowed only for noncommercial distribution and only if you received the program in object code or executable form with such an offer, in accord with Subsection b above.)
But his assumption about how kernel modules work is completely wrong.. though the INTENT might be something like he describes, it's not what Linus said.
The Linux kernel license says you can code proprietary modules, as long as the interface is part of the stock kernel (in other words, GPL)
So you can make a proprietary network driver, as long you don't haev to modify the main kernel to get it to work; you are under no obligation to release that source at all. If you have some way of hacking an entire realtime OS to look like a network drive to the kernel, that would comply.
So, linksys should be redistributing the linux sources, however, if their custom work is confined to modules & userland code, they are under no obligation to release the source to those drives. And as linux already has a kernel interface for network & wireless network, there is no reason to expect them to release that code.
Not only are they in violation of the GPL, they are literally costing SCO BILLIONS OF DOLLARS by violating SCO's copyrights, patents, or some contract with IBM by releasing a Linux based product! Quick, someone alert McBride!
Do you have ESP?
Just been hacking around a Belkin 54k WAP/Router box I bought a few weeks back. NMap identifies it as Linux 2.4.0-2.4.5.
...
The Belkin Networking downloads page gives an updated firmware for this. Sure enough, at offset 790393 there's a CRAM Filesystem. Mounting that shows a stock 2.4.5 kernel with three custom modules (one for the wireless card, one for the ethernet card, one for the front panel LEDs). These three modules aside it looks like non-modified GPL stuff.
However, reading any of the binary files shows the string : "GCC: (GNU) 3.0 20010422 (prerelease) with bcm4710a0 modifications" - Modifications you say? Oh dear, I don't remember seeing a Broadcom patch submitted to GCC
<BusyBox maintainer hat on>
S _code.bin
./cramfs.image /mnt /mnt/bin /mnt/bin/busybox /mnt/bin/busybox | grep BusyBoxd d /mnt/bin/busybox
This is what I did to verify that the Linksys firmware was violating the GPL....
#!/bin/sh
wget ftp://ftp.linksys.com/pub/network/WRT54G_1.02.1_U
# I noticed a GZIP signature for a file name "piggy" at offset
# 60 bytes from the start, suggesting we have a compressed Linux
# kernel
dd if=WRT54G_1.02.1_US_code.bin bs=60 skip=1 | zcat > kernel
# Noticed there was a cramfs magic signature at offset 786464
dd if=WRT54G_1.02.1_US_code.bin of=cramfs.image bs=786464 skip=1
file cramfs.image
sudo mount -o loop,ro -t cramfs
ls -la
file
strings
/usr/i386-linux-uclibc/bin/i386-uclibc-l
-Erik -- --This message was written using 73% post-consumer electrons--
Think of this as a check on honesty of GPL adherents. If you don't make the offer or even admit that there is GPLed code in your product, you are probably doing it for a reason (i.e. you are hiding something). If they really aren't hiding anything, and it was a simple oversight, then why don't they reply to emails about it and just point out that no modifications were made, and stick a source mirror up on their FTP site? The cost is practically nil to them to adhere to the license, assuming they are playing by the rules, so what's the big deal?