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<title>Libreboot documentation: Security on the ThinkPad X60</title>
</head>
<body>
<header>
<h1>Security on the ThinkPad X60</h1>
<aside>Hardware modifications to enhance security on the ThinkPad X60. This tutorial is <b>incomplete</b> at the time of writing.</aside>
</header>
<p>Or go <a href="../index.html">back to main index</a></p>
<h2>Table of Contents</h2>
<ul>
<li><a href="#hardware_requirements">Hardware Requirements</a></li>
<li><a href="#software_requirements">Software Requirements</a></li>
<li><a href="#procedure">The procedure</a></li>
</ul>
<h1 id="hardware_requirements">Hardware requirements</h1>
<ul>
<li>An X60</li>
<li>screwdriver</li>
<li>(in a later version of this tutorial: soldering iron and scalpel)</li>
</ul>
<h1 id="software_requirements">Software requirements</h1>
<ul>
<li>none (at least in the scope of the article as-is)</li>
<li>You probably want to encrypt your GNU/Linux install using LUKS</li>
</ul>
<h1>
Rationale
</h1>
<p>
Most people think of security on the software side: the hardware is important aswell.
Hardware security is useful in particular to journalists (or activists in a given movement) who need absolute privacy in their work.
It is also generally useful to all those that believe security and privacy are inalienable rights.
Security starts with the hardware; crypto and network security come later.
</p>
<p>
Paradoxically, going this far to increase your security also makes you a bigger target.
At the same time, it protects you in the case that someone does attack your machine.
This paradox only exists while few people take adequate steps to protect yourself: it is your <b>duty</b>
to protect yourself, not only for your benefit but to make strong security <i>normal</i> so
that those who do need protection (and claim it) are a smaller target against the masses.
</p>
<p>
Even if there are levels of security beyond your ability (technically, financially and so on)
doing at least <i>something</i> (what you are able to do) is extremely important.
If you use the internet and your computer without protection, attacking you is cheap (some say it is
only a few US cents). If everyone (majority of people) use strong security by default,
it makes attacks more costly and time consuming; in effect, making them disappear.
</p>
<p>
This tutorial deals with reducing the number of devices that have direct memory access that
could communicate with inputs/outputs that could be used to remotely
command the machine (or leak data).
</p>
<h1 id="procedure">Disassembly</h1>
<p>
Firstly remove the bluetooth (if your X60 has this):<br/>
The marked screws are underneath those stickers (marked in those 3 locations at the bottom of the LCD assembly):<br/>
<img src="x60_security/0000_bluetooth0.jpg" alt="" /><br/>
Now gently pry off the bottom part of the front bezel, and the bluetooth module is on the left (easily removable):<br/>
<img src="x60_security/0000_bluetooth.jpg" alt="" /><br/>
</p>
<p>
If your model was WWAN, remove the simcard (check anyway):<br/>
Uncover those 2 screws at the bottom:<br/>
<img src="x60_security/0000_simcard0.jpg" alt="" /><br/>
SIM card (not present in the picture) is in the marked location:<br/>
<img src="x60_security/0000_simcard1.jpg" alt="" /><br/>
Replacement: USB dongle.
</p>
<p>
Now get into the motherboard.
</p>
<p>
Remove those screws:<br/>
<img src="x60_security/0000.jpg" alt="" />
</p>
<p>
Push the keyboard forward (carefully):<br/>
<img src="x60_security/0001.jpg" alt="" />
</p>
<p>
Lift the keyboard up and disconnect it from the board:<br/>
<img src="x60_security/0002.jpg" alt="" />
</p>
<p>
Grab the right-hand side of the chassis and force it off (gently) and pry up the rest of the chassis:<br/>
<img src="x60_security/0003.jpg" alt="" />
</p>
<p>
You should now have this:<br/>
<img src="x60_security/0004.jpg" alt="" />
</p>
<p>
The following is a summary of what you will remove (already done to this machine):<br/>
<img src="x60_security/0001_overview.jpg" alt="" /><br/>
Note: the blue lines represent antenna cables and modem cables. You don't need to remove these, but you can if you want
(to make it tidier after removing other parts). I removed the antenna wires, the modem jack, the modem cable and
also (on another model) a device inside the part where the wwan antenna goes (wasn't sure what it was, but I knew it wasn't needed). <b>This is optional</b>
</p>
<p>
Remove the microphone (can desolder it, but you can also easily pull it off with you hands). Already removed here:<br/>
<img src="x60_security/0001_microphone.jpg" alt="" /><br/>
<b>Rationale:</b><br/>
Another reason to remove the microphone: If your computer gets<a href="#ref1">[1]</a> compromised, it can
record what you say, and use it to receive data from nearby devices if
they're compromised too. Also, we do not know what the built-in microcode (in the CPU) is doing; it could theoretically
be programmed to accept remote commands from some speaker somewhere (remote security hole). <b>In other words,
the machine could already be compromised from the factory.</b>
</p>
<p>
Remove the modem:<br/>
<img src="x60_security/0001_modem.jpg" alt="" /><br/>
(useless, obsolete device)
</p>
<p>
Remove the speaker:<br/>
<img src="x60_security/0001_speaker.jpg" alt="" /><br/>
Reason: combined with the microphone issue, this could be used to leak data.<br/>
If your computer gets<a href="#ref1">[1]</a> compromised, it can be used to
transmit data to nearby compromised devices. It's unknown if it can be
turned into a microphone<a href="#ref2">[2]</a>.<br/>
Replacement: headphones/speakers (line-out) or external DAC (USB).
</p>
<p>
Remove the wlan (also remove wwan if you have it):<br/>
<img src="x60_security/0001_wlan_wwan.jpg" alt="" /><br/>
Reason: has direct (and very fast) memory access, and could (theoretically) leak data over a side-channel.<br/>
<b>Wifi:</b> The ath5k/ath9k cards might not have firmware at all. They might safe but could have
access to the computer's RAM trough DMA. If people have an intel
card(most X60's come with Intel wifi by default, until you change it),then that card runs
a non-free firwamre and has access to the computer's RAM trough DMA! So
it's risk-level is very high.<br/>
<b>Wwan (3d modem):</b> They run proprietary software and have access to the
computer's RAM! So it's like AMT but over the GSM network which is
probably even worse.<br/>
Replacement: external USB wifi dongle. (or USB wwan/3g dongle; note, this has all the same privacy issues as mobile phones. wwan not recommended).
</p>
<h2>
Not covered yet:
</h2>
<ul>
<li>Disable cardbus (has fast/direct memory access)</li>
<li>Disable firewire (has fast/direct memory access)</li>
<li>Disable flashing the ethernet firmware</li>
<li>Disable SPI flash writes (can be re-enabled by unsoldering two parts)</li>
<li>Disable use of xrandr/edid on external monitor (cut 2 pins on VGA)</li>
<li>Disable docking station (might be possible to do it in software, in coreboot upstream as a Kconfig option)</li>
</ul>
<p>
Go to <a href="http://media.ccc.de/browse/congress/2013/30C3_-_5529_-_en_-_saal_2_-_201312271830_-_hardening_hardware_and_choosing_a_goodbios_-_peter_stuge.html">http://media.ccc.de/browse/congress/2013/30C3_-_5529_-_en_-_saal_2_-_201312271830_-_hardening_hardware_and_choosing_a_goodbios_-_peter_stuge.html</a>
or directly to the video: <a href="http://mirror.netcologne.de/CCC/congress/2013/webm/30c3-5529-en-Hardening_hardware_and_choosing_a_goodBIOS_webm.webm">http://mirror.netcologne.de/CCC/congress/2013/webm/30c3-5529-en-Hardening_hardware_and_choosing_a_goodBIOS_webm.webm</a>.
</p>
<p>
A lot of this tutorial is based on that video. Look towards the second half of the video to see how to do the above.
</p>
<h2>
Also not covered yet:
</h2>
<ul>
<li>
Intrusion detection: randomized seal on screws<br/>
Just put nail polish with lot of glider on the important screws, take
some good pictures. Keep the pictueres and make sure of their integrity.
Compare the nail polish with the pictures before powering on the laptop.
</li>
<li>
Tips about preventing/mitigating risk of cold boot attack.
<ul>
<li>soldered RAM?</li>
<li>seal RAM door shut (possibly modified lower chassis) so that system has to be disassembled (which has to go through the nail polish)</li>
<li>wipe all RAM at boot/power-off/power-on? (patch in coreboot upstream?)</li>
<li>ask gnutoo about fallback patches (counts number of boots)</li>
</ul>
</li>
<li>
Software-based security hardening (GRUB trust/cryptomount, kernel LUKS/ecryptfs, etc).
<ul>
<li>modify grub to delay password attemps by a few seconds, and fail after a set time (and record all attemps in a counter, writing that to nvram)</li>
</ul>
</li>
<li>
General tips/advice and web links showing how to detect physical intrusions.
</li>
<li>
For example: <a href="http://cs.tau.ac.il/~tromer/acoustic/">http://cs.tau.ac.il/~tromer/acoustic/</a>
</li>
<li>
https://gitorious.org/gnutoo-for-coreboot/grub-assemble/source/a61f636797777a742f65f4c9c58032aa6a9b23c3:
</li>
</ul>
<h1>
Extra notes
</h1>
<p>
EC: Cannot be removed but can be mitigated: it contains non-free
non-loadable code, but it has no access to the computer's RAM.
It has access to the on-switch of the wifi, bluetooth, modem and some
other power management features. The issue is that it has access to the
keyboard, however if the software security howto <b>(not yet written)</b> is followed correctly,
it won't be able to leak data to a local attacker. It has no network
access but it may still be able to leak data remotely, but that
requires someone to be nearby to recover the data with the help of an
SDR and some directional antennas<a href="#ref3">[3]</a>.
</p>
<h2>
Risk level
</h2>
<ul>
<li>Modem (3g/wwan): highest</li>
<li>Intel wifi: Near highest</li>
<li>Atheros PCI wifi: unknown, but lower than intel wifi.</li>
<li>Microphone: only problematic if the computer gets compromised.</li>
<li>Speakers: only problematic if the computer gets compromised.</li>
<li>EC: can be mitigated if following the <b>(not yet written)</b> guide on software security.</li>
</ul>
<h1>
References
</h1>
<h2 id="ref1">[1] physical access</h2>
<p>
Explain that black hats, TAO, and so on might use a 0day to get in,
and explain that in this case it mitigates what the attacker can do.
Also the TAO do some evaluation before launching an attack: they take
the probability of beeing caught into account, along with the kind of
target. A 0day costs a lot of money, I heard that it was from 100000$
to 400000$, some other websites had prices 10 times lower but that
but it was probably a typo. So if people increase their security it
makes it more risky and more costly to attack people.
</p>
<h2 id="ref2">[2] microphone</h2>
<p>
It's possible to turn headphones into a microphone, you could try
yourself, however they don't record loud at all. Also intel cards have
the capability to change a connector's function, for instance the
microphone jack can now become a headphone plug, that's called
retasking. There is some support for it in GNU/Linux but it's not very
well known.
</p>
<h2 id="ref3">[3] Video (CCC)</h2>
<p>
30c3-5356-en-Firmware_Fat_Camp_webm.webm from the 30th CCC. While
their demo is experimental(their hardware also got damaged during the
transport), the spies probably already have that since a long time.
<a href="http://berlin.ftp.media.ccc.de/congress/2013/webm/30c3-5356-en-Firmware_Fat_Camp_webm.webm">http://berlin.ftp.media.ccc.de/congress/2013/webm/30c3-5356-en-Firmware_Fat_Camp_webm.webm</a>
</p>
<hr/>
<p>
Copyright © 2014 Francis Rowe, All Rights Reserved.<br/>
See <a href="../license.html">../license.html</a> for license conditions.
</p>
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