\item Purchase a new router and cable anew, and reattempt the installation

     process while taking extra care not to miswire any cables.

   \item Seek assistance from the libreCMC community to find an alternative

     method of installation.

\end{itemize}

The investigator chose the latter and then contacted a libreCMC developer

familiar with the product.  That developer, who  agreed the the RX pin was

likely ruined, described an alternative method for console access using the

{\tt netcat}.  The libreCMC developer described the process as follows:

\begin{quotation}

  \begin{itemize}

  \item Change the IP address of the router to 192.168.1.1.

  \item Change the IP address of a desktop GNU/Linux system to 192.168.1.2.

  \item Power on the router while holding the reset button for 7 seconds.

  \item Use the {\tt netcat} command (as below) on the desktop, and press

    enter to receive U-Boot's prompt:

\lstset{tabsize=2}

\begin{lstlisting}[language=bash]

$ nc -u -p 6666 192.168.1.1 6666

uboot>

\end{lstlisting}

  \end{itemize}

\end{quotation}

Upon following this procedure, the investigator was able to confirm the

(original) shipped version of U-Boot was still installed:

\begin{lstlisting}[language=bash]

$ nc -u -p 6666 192.168.1.1 6666

uboot> version

U-Boot 1.1.4 (Jul 28 2014)

\end{lstlisting}

Thereafter, the investigator followed the instructions from

``u-boot\verb0_0reflash''.  Specifically, the investigator configured a TFTP server

and placed the newly built firmware into \texttt{/srv/tftp}.  The investigator

also followed the remaining instructions in ``u-boot\verb0_0reflash'', but

used the \texttt{netcat} console rather than the serial console, and

used U-Boot's \texttt{reset} command to reboot the router.

Upon reboot, the serial console (still connect with working output) showed

the message \texttt{U-Boot 1.1.4  (Oct 17 2014)}, and thus confirmed a

successful reflash of the U-Boot image built by the investigator.

\section{Firmware Comparison}

Next, to ensure the CCS did indeed correspond to the firmware original

installed on the TPE-NWIFIROUTER, the investigator compared the built

firmware image with the filesystem originally found on the device itself.

The comparison steps were as follows:

\begin{enumerate}

\item Extract the filesystem from the image we built by running

  \href{https://gitorious.org/copyleft-org/gpl-compliance-scripts/source/master:find-firmware.pl}{find-firmware.pl}

  on ``bin/ar71xx/librecmc-ar71xx-generic-tl-wr841n-v8-squashfs-factory.bin''

  and then running

  \href{http://www.binaryanalysis.org/en/content/show/download}{bat-extratools}'

  ``squashfs4.2/squashfs-tools/bat-unsquashfs42'' on the resulting

  morx0.squash, using the filesystem in the new squashfs-root directory for

  comparison.

\item Login to the router's web interface (at \url{http://192.168.10.1/ }) from a computer

  connected to the router.

\item Set a password using the provided link at the top (since the router's

  UI warns that no password is set and asks the user to change it).

\item Logged into the router via SSH, using the root user with the

  aforementioned password.

\item Compared representative directory listings and binaries to ensure the set of

  included files (on the router) is similar to those found in the firmware

  image that the investigator created (whose contents are now in the local squashfs-root directory).  In

  particular, the investigator did the following comparisons:

  \begin{enumerate}

  \item Listed the /bin folder (``ls -l /bin'') and confirm the list of files is the same

    and that the file sizes are similar.

  \item Checked the ``strings'' output of ``/bin/busybox'' to confirm it is similar in both

   places (similar number of lines and content of lines).  (One cannot directly

   compare the binaries because the slight compilation variations will cause

   some bits to be different.)

 \item Repeated the above two steps for ``/lib/modules'', ``/usr/bin'', and other directories with

   a significant number of binaries.

 \item Checked that the kernel was sufficiently similar.  The investigator

   compared the ``dmesg'' output both before and after flashing the new

   firmware.  As the investigator expected, the kernel version string was

   similar, but had a different build date and user@host indicator.  (The

   kernel binary itself is not easily accessible from an SSH login, but was

   retrievable using the U-Boot console (the start address of the kernel in

   flash appears to be 0x9F020000, based on the boot messages seen in the

   serial console).

  \end{enumerate}

\end{enumerate}

\section{Minor Annoyances}

As discussed in detail above, there were a few minor annoyances, none of

which were GPL violations.  Rather, the annoyances briefly impeded the

build and installation.  However, the investigator, as a reasonably skilled

build engineer for embedded devices, was able to complete the process with

the instructions provided.

To summarize, no GPL compliance issues were found, and the CCS release was

one of the best ever reviewed by any investigator at any community-oriented

enforcement organization.  However, the following annoyances were discovered:

\begin{itemize}

\item Failure to explain how to extract the source tarball and then where to run the

  ``make'' command.

\item Failure to explain how to install the kernel and root filesystem on the

  device; the user must assume the web UI must be used.

\item Including pre-built toolchain binaries that don't work on all systems,

  and failure to copy and/or symlink built toolchain binaries in the right location.

\item Failure to include information in the U-Boot installation instructions for

  wiring the serial cable.

\item Ideally, the U-Boot installation instructions would also include the

  {\tt netcat} method of installation.

\item Finally, the instructions should note that the new U-Boot firmware

  should be placed into \texttt{/srv/tftp} when using TFTP on most GNU/Linux

  desktops.

\end{itemize}

Thus, no CCS is absolutely perfect, but GPL violation investigators always

give the distributors the benefit of any doubts and seek to work with the

vendors and improve their CCS for the betterment of their users, customers,

and the entire software freedom community.

\section{Lessons Learned}

Companies that seek to redistribute copylefted software can benefit greatly

from ThinkPenguin's example.  Here are just a few of the many lessons that

can be learned here:

\begin{enumerate}

\item Even though copyleft licenses have them,

  \hyperref[thinkpenguin-included-ccs]{\bf avoid the offer-for-source

    provisions}.  Not only does including the CCS alongside binary

  distribution make violation investigation and compliance confirmation

  substantially easier, but also (and more importantly) doing so

  \hyperref[offer-for-source]{completes the distributor's CCS compliance

    obligations at the time of distribution} (provided, of course, that the

  distributor is otherwise in compliance with the relevant copyleft license).

\item {\bf Include top-level build instructions in a natural language (such

  as English) in a \hyperref[thinkpenguin-toplevel-readme]{clear and

    conspicuous place}.}  Copyleft licenses require that someone reasonably

  skilled in the art can reproduce the build and installation.  Typically,

  instructions written in English are necessary, and often easier than writing

  programmed scripts.  The ``script'' included can

  certainly be more like the script of a play and less like a Bash script.

\item {\bf Write build/install instructions to the appropriate level of

  specificity}.  The upstream engineers

  in this case study \hyperref[thinkpenguin-specific-host-system]{clearly did

    additional work to ensure functionality on a wide variety of host build

    systems}; this is quite rare.  When in doubt, include the maximum level

  of detail build engineers can provide with the CCS instructions, but also

  double-check to investigate if a more generalized solution (such as other

  host systems) work just as well for the build.

\item {\bf Seek to adhere to the spirit of copyleft, not just the letter of

  the license}.  Encouragement of users to improve and

  make their devices better is one of ThinkPenguin's commercial differentiators.  Copyleft advocates

  that other companies have undervalued the large and lucrative

  market of

  users who seek hackable devices.  By going beyond the

  mere minimal requirements of GPL, companies can immediately reap the

  benefits in that target market.

  \item Community-oriented enforcement organizations do not play ``gotcha''\footnote{For lack of a better

    phrase.} with distributors regarding GPL

    violations.  The goal in the GPL enforcement process is to achieve

    compliance and correct mistakes and annoyances.  Such organizations

    due to honest error rather than malicious action '' approach.  The goal

    is compliance (in direct contrast with

    the \hyperref[Proprietary Relicensing]{discussion in \S~\ref*{Proprietary Relicensing} about the

      proprietary relicensing} business model).

\end{enumerate}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\chapter{Bortez: Modified GCC SDK}

In our first case study, we will consider Bortez, a company that

produces software and hardware toolkits to assist OEM vendors, makers

of consumer electronic devices.

\section{Facts}

One of Bortez's key products is a Software Development Kit (``SDK'')

designed to assist developers building software for a specific class of

consumer electronics devices.

FSF received a report that the SDK may be based on the GNU Compiler

Collection (which is an FSF-copyrighted collection of tools for software

development in C, C++ and other popular languages). FSF investigated the

claim, but was unable to confirm the violation. The violation reporter

was unresponsive to follow-up requests for more information.

Since FSF was unable to confirm the violation, we did not pursue it any

further. Bogus reports do happen, and we do not want to burden companies

with specious GPL violation complaints. FSF shelved the matter until

more evidence was discovered.

FSF was later able to confirm the violation when two additional reports

surfaced from other violation reporters, both of whom had used the SDK

professionally and noticed clear similarities to FSF's GNU GCC\@. FSF's

Compliance Engineer asked the reporters to run standard tests to confirm

the violation, and it was confirmed that Bortez's SDK was indeed a

modified version of GCC\@. Bortez had ported to Windows and added a number

of features, including support for a specific consumer device chipset and

additional features to aid in the linking process (``LP'') for those

specific devices. FSF explained the rights that the GPL afforded these

customers and pointed out, for example, that Bortez only needed to provide

source to those in possession of the binaries, and that the users may need

to request that source (if \S 3(b) was exercised). The violators

confirmed that such requests were not answered.

FSF brought the matter to the attention of Bortez, who immediately

escalated the matter to their attorneys. After a long negotiation,

Bortez acknowledged that their SDK was indeed a modified version of

GCC\@. Bortez released most of the source, but some disagreement

occurred over whether LP was also derivative of GCC\@. After repeated

FSF inquiries, Bortez reaudited the source to discover that FSF's

analysis was correct. Bortez determined that LP included a number of

source files copied from the GCC code-base.

\label{davrik-build-problems}

Once the full software release was made available, FSF asked the violation

reporters if it addressed the problem. Reports came back that the source

did not properly build. FSF asked Bortez to provide better build

instructions with the software, and such build instructions were

incorporated into the next software release.

At FSF's request as well, Bortez informed customers who had previously

purchased the product that the source was now available by announcing

the availability on its Web site and via a customer newsletter.

Bortez did have some concerns regarding patents. They wished to include a

statement with the software release that made sure they were not granting

any patent permission other than what was absolutely required by the GPL\@.

They understood that their patent assertions could not trump any rights

granted by the GPL\@. The following language was negotiated into the release:

\begin{quotation}

Subject to the qualifications stated below, Bortez, on behalf of itself

and its Subsidiaries, agrees not to assert the Claims against you for your

making, use, offer for sale, sale, or importation of the Bortez's GNU

Utilities or derivative works of the Bortez's GNU Utilities

(``Derivatives''), but only to the extent that any such Derivatives are

licensed by you under the terms of the GNU General Public License. The

Claims are the claims of patents that Bortez or its Subsidiaries have

standing to enforce that are directly infringed by the making, use, or

sale of an Bortez Distributed GNU Utilities in the form it was distributed

by Bortez and that do not include any limitation that reads on hardware;

the Claims do not include any additional patent claims held by Bortez that

cover any modifications of, derivative works based on or combinations with

the Bortez's GNU Utilities, even if such a claim is disclosed in the same

patent as a Claim. Subsidiaries are entities that are wholly owned by

Bortez.

This statement does not negate, limit or restrict any rights you already

have under the GNU General Public License version 2.

\end{quotation}

This quelled Bortez's concerns about other patent licensing they sought to

do outside of the GPL'd software, and satisfied FSF's concerns that Bortez

give proper permissions to exercise teachings of patents that were

exercised in their GPL'd software release.

Finally, a GPL Compliance Officer inside Bortez was appointed to take

responsibility for all matters of GPL compliance inside the company.

Bortez is responsible for informing FSF if the position is given to

someone else inside the company, and making sure that FSF has direct

contact with Bortez's Compliance Officer.

\section{Lessons}

This case introduces a number of concepts regarding GPL enforcement.

\begin{enumerate}

\item {\bf Enforcement should not begin until the evidence is confirmed.}

  Most companies that distribute GPL'd software do so in compliance, and at

  times, violation reports are mistaken. Even with extensive efforts in

  GPL education, many users do not fully understand their rights and the

  obligations that companies have. By working through the investigation

  with reporters, the violation can be properly confirmed, and {\bf the

    user of the software can be educated about what to expect with GPL'd

    software}. When users and customers of GPL'd products know their

  rights, what to expect, and how to properly exercise their rights

  (particularly under \S 3(b)), it reduces the chances for user

  frustration and inappropriate community outcry about an alleged GPL

  violation.

\item {\bf GPL compliance requires friendly negotiation and cooperation.}

  Often, attorneys and managers are legitimately surprised to find out

  GPL'd software is included in their company's products. Engineers

  sometimes include GPL'd software without understanding the requirements.

  This does not excuse companies from their obligations under the license,

  but it does mean that care and patience are essential for reaching GPL

  compliance. We want companies to understand that participating and

  benefiting from a collaborative Free Software community is not a burden,

  so we strive to make the process of coming into compliance as smooth as

  possible.

\item {\bf Confirming compliance is a community effort.}  The whole point

  of making sure that software distributors respect the terms of the GPL is to

  allow a thriving software sharing community to benefit and improve the

  work. FSF is not the expert on how a compiler for consumer electronic

  devices should work. We therefore inform the community who originally

  brought the violation to our attention and ask them to assist in

  evaluation and confirmation of the product's compliance. Of course, FSF

  coordinates and oversees the process, but we do not want compliance for

  compliance's sake; rather, we wish to foster a cooperating community of

  development around the Free Software in question, and encourage the

  once-violator to begin participating in that community.

\item {\bf Informing the harmed community is part of compliance.} FSF asks

  violators to make some attempt --- such as via newsletters and the

  company's Web site --- to inform those who already have the products as

  to their rights under the GPL\@. One of the key thrusts of the GPL's \S 1 and

  \S 3 is to {\em make sure the user knows she has these rights\/}. If a

  product was received out of compliance by a customer, she may never

  actually discover that she has such rights. Informing customers, in a

  way that is not burdensome but has a high probability of successfully

  reaching those who would seek to exercise their freedoms, is essential

  to properly remedy the mistake.

\item {\bf Lines between various copyright, patent, and other legal

  mechanisms must be precisely defined and considered.}  The most

  difficult negotiation point of the Bortez case was drafting language

  that simultaneously protected Bortez's patent rights outside of the

  GPL'd source, but was consistent with the implicit patent grant in

  the GPL\@. As we discussed in the first course of this series, there is

  indeed an implicit patent grant with the GPL, thanks to \S 6 and \S 7.

  However, many companies become nervous and wish to make the grant

  explicit to assure themselves that the grant is sufficiently narrow for

  their needs. We understand that there is no reasonable way to determine

  what patent claims read on a company's GPL holdings and which do not, so

  we do not object to general language that explicitly narrows the patent

  grant to only those patents that were, in fact, exercised by the GPL'd

  software as released by the company.

\end{enumerate}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\chapter{Bracken: a Minor Violation in a GNU/Linux Distribution}

In this case study, we consider a minor violation made by a company whose

knowledge of the Free Software community and its functions is deep.

\section{The Facts} 

Bracken produces a GNU/Linux operating system product that is sold

primarily to OEM vendors to be placed in appliance devices used for a

single purpose, such as an Internet-browsing-only device. The product

is almost 100\% Free Software, mostly licensed under the GPL and related

Free Software licenses.

FSF found out about this violation through a report first posted on a

  Slashdot\footnote{Slashdot is a popular news and discussion site for

  technical readers.} comment, and then it was brought to our attention again

  by another Free Software copyright holder who had discovered the

  same violation.