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| author | Francis Rowe <info@gluglug.org.uk> | 2014-11-05 20:52:36 (EST) |
|---|---|---|
| committer | Francis Rowe <info@gluglug.org.uk> | 2014-11-05 20:52:36 (EST) |
| commit | 8b2219bfa2da36e7809588ef723a10483a6e137f (patch) | |
| tree | 8c4d74b9efbdabc1a2604b8cbd508c006c225241 /docs/security | |
| parent | 7429bdcdbb4fc51c61897115112468642afeecfc (diff) | |
| download | libreboot-8b2219bfa2da36e7809588ef723a10483a6e137f.zip libreboot-8b2219bfa2da36e7809588ef723a10483a6e137f.tar.gz libreboot-8b2219bfa2da36e7809588ef723a10483a6e137f.tar.bz2 | |
Documentation: *major* cleanup.
Cleanup was long overdue. Old structure was messy and inefficient.
Diffstat (limited to 'docs/security')
| -rw-r--r-- | docs/security/dock.html | 154 | ||||
| -rw-r--r-- | docs/security/index.html | 40 | ||||
| -rw-r--r-- | docs/security/t60_security.html | 440 | ||||
| -rw-r--r-- | docs/security/x60_security.html | 301 |
4 files changed, 935 insertions, 0 deletions
diff --git a/docs/security/dock.html b/docs/security/dock.html new file mode 100644 index 0000000..2b7fe75 --- /dev/null +++ b/docs/security/dock.html @@ -0,0 +1,154 @@ +<!DOCTYPE html> +<html> +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1"> + + <style type="text/css"> + @import url('css/main.css'); + </style> + + <title>Notes about DMA and the docking station (X60/T60)</title> +</head> + +<body> + <header> + <h1>Notes about DMA and the docking station (X60/T60)</h1> + </header> + +<pre> + +Use case: +--------- +Usually when people do full disk encryption, it's not really full disk, +instead they still have a /boot in clear. + +So an evil maid attack can still be done, in two passes: +1) Clone the hdd, Infect the initramfs or the kernel. +2) Wait for the user to enter its password, recover the password, +luksOpen the hdd image. + +I wanted a real full-disk encryption so I've put grub in flash and I +have the following: The HDD has a LUKS rootfs(containing /boot) on an +lvm partition, so no partition is in clear. + +So when the computer boots it executes coreboot, then grub as a payload. +Grub then opens the LUKS partition and loads the kernel and initramfs +from there. + +To prevent hardware level tempering(like reflashing), I used nail +polish with a lot of gilder, that acts like a seal. Then a high +resolution picture of it is taken, to be able to tell the difference. + +The problem: +------------ +But then comes the docking port issue: Some LPC pins are exported +there, such as the CLKRUN and LDRQ#. + +LDRQ# is "Encoded DMA/Bus Master Request": "Only needed by +peripherals that need DMA or bus mastering. Requires an +individual signal per peripheral. Peripherals may not share +an LDRQ# signal." + +So now DMA access is possible trough the dock connector. +So I want to be able to turn that off. + +If I got it right, the X60 has 2 superio, one is in the dock, and the +other one is in the laptop, so we have: + ________________ + _________________ | | +| | | Dock connector:| +|Dock: NSC pc87982|<--LPC--->D_LPC_DREQ0 | +|_________________| |_______^________| + | + | + | + | + ___________________|____ + | v | + | SuperIO: DLDRQ# | + | NSC pc87382 LDRQ# | + |___________________^____| + | + | + | + | + ___________________|___ + | v | + | Southbridge: LDRQ0 | + | ICH7 | + |_______________________| + + +The code: +--------- +Now if I look at the existing code, there is some superio drivers, like +pc87382 in src/superio/nsc, the code is very small. +The only interesting part is the pnp_info pnp_dev_info struct. + +Now if I look inside src/mainboard/lenovo/x60 there is some more +complete dock driver: + +Inside dock.c I see some dock_connect and dock_disconnect functions. + +Such functions are called during the initialisation (romstage.c) and +from the x60's SMI handler (smihandler.c). + +Questions: +---------- +1) Would the following be sufficent to prevent DMA access from the +outside: +> int dock_connect(void) +> { +> int timeout = 1000; +> + int val; +> + +> + if (get_option(&val, "dock") != CB_SUCCESS) +> + val = 1; +> + if (val == 0) +> + return 0; +> [...] +> } +> +> void dock_disconnect(void) { +> + if (dock_present()) +> + return; +> [...] +> } +2) Would an nvram option be ok for that? Should a Kconfig option be +added too? + +> config DOCK_AUTODETECT +> bool "Autodetect" +> help +> The dock is autodetected. If unsure select this option. +> +> config DOCK_DISABLED +> bool "Disabled" +> help +> The dock is always disabled. +> +> config DOCK_NVRAM_ENABLE +> bool "Nvram" +> help +> The dock autodetection is tried only if it is also enabled +> trough nvram. + +</pre> + +<hr/> + + <p> + Copyright © 2014 Francis Rowe <info@gluglug.org.uk><br/> + This document is released under the Creative Commons Attribution-ShareAlike 4.0 International Public License and all future versions. + A copy of the license can be found at <a href="../license.txt">../license.txt</a>. + </p> + + <p> + This document is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See <a href="../license.txt">../license.txt</a> for more information. + </p> + +</body> +</html> diff --git a/docs/security/index.html b/docs/security/index.html new file mode 100644 index 0000000..64008b8 --- /dev/null +++ b/docs/security/index.html @@ -0,0 +1,40 @@ +<!DOCTYPE html> +<html> +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1"> + + <style type="text/css"> + @import url('../css/main.css'); + </style> + + <title>Security topics</title> +</head> + +<body> + + <h1 id="pagetop">Security topics</h1> + <p> + Or <a href="../index.html">Back to main index</a>. + </p> + <ul> + <li><a href="x60_security.html">ThinkPad X60/X60S: hardware security</a></li> + <li><a href="t60_security.html">ThinkPad T60: hardware security</a></li> + </ul> + +<hr/> + + <p> + Copyright © 2014 Francis Rowe <info@gluglug.org.uk><br/> + This document is released under the Creative Commons Attribution-ShareAlike 4.0 International Public License and all future versions. + A copy of the license can be found at <a href="../license.txt">../license.txt</a>. + </p> + + <p> + This document is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See <a href="../license.txt">../license.txt</a> for more information. + </p> + +</body> +</html> diff --git a/docs/security/t60_security.html b/docs/security/t60_security.html new file mode 100644 index 0000000..eb3db03 --- /dev/null +++ b/docs/security/t60_security.html @@ -0,0 +1,440 @@ +<!DOCTYPE html> +<html> +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1"> + + <style type="text/css"> + @import url('../css/main.css'); + </style> + + <title>Libreboot documentation: Security on the ThinkPad T60</title> +</head> + +<body> + + <header> + <h1>Security on the ThinkPad T60</h1> + <aside>Hardware modifications to enhance security on the ThinkPad T60. 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>A T60</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> + Remove those screws and remove the HDD:<br/> + <img src="../images/t60_dev/0001.JPG" alt="" /> <img src="../images/t60_dev/0002.JPG" alt="" /> + </p> + + <p> + Lift off the palm rest:<br/> + <img src="../images/t60_dev/0003.JPG" alt="" /> + </p> + + <p> + Lift up the keyboard, pull it back a bit, flip it over like that and then disconnect it from the board:<br/> + <img src="../images/t60_dev/0004.JPG" alt="" /> <img src="../images/t60_dev/0005.JPG" alt="" /> <img src="../images/t60_dev/0006.JPG" alt="" /> + </p> + + <p> + Gently wedge both sides loose:<br/> + <img src="../images/t60_dev/0007.JPG" alt="" /> <img src="../images/t60_dev/0008.JPG" alt="" /> + </p> + + <p> + Remove that cable from the position:<br/> + <img src="../images/t60_dev/0009.JPG" alt="" /> <img src="../images/t60_dev/0010.JPG" alt="" /> + </p> + + <p> + Now remove that bezel. Remove wifi, nvram battery and speaker connector (also remove 56k modem, on the left of wifi):<br/> + <img src="../images/t60_dev/0011.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 T60'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. + </p> + + <p> + Remove those screws:<br/> + <img src="../images/t60_dev/0012.JPG" alt="" /> + </p> + + <p> + Disconnect the power jack:<br/> + <img src="../images/t60_dev/0013.JPG" alt="" /> + </p> + + <p> + Remove nvram battery (we will put it back later):<br/> + <img src="../images/t60_dev/0014.JPG" alt="" /> + </p> + + <p> + Disconnect cable (for 56k modem) and disconnect the other cable:<br/> + <img src="../images/t60_dev/0015.JPG" alt="" /> <img src="../images/t60_dev/0016.JPG" alt="" /> + </p> + + <p> + Disconnect speaker cable:<br/> + <img src="../images/t60_dev/0017.JPG" alt="" /> + </p> + + <p> + Disconnect the other end of the 56k modem cable:<br/> + <img src="../images/t60_dev/0018.JPG" alt="" /> + </p> + + <p> + Make sure you removed it:<br/> + <img src="../images/t60_dev/0019.JPG" alt="" /> + </p> + + <p> + Unscrew those:<br/> + <img src="../images/t60_dev/0020.JPG" alt="" /> + </p> + + <p> + Make sure you removed those:<br/> + <img src="../images/t60_dev/0021.JPG" alt="" /> + </p> + + <p> + Disconnect LCD cable from board:<br/> + <img src="../images/t60_dev/0022.JPG" alt="" /> + </p> + + <p> + Remove those screws then remove the LCD assembly:<br/> + <img src="../images/t60_dev/0023.JPG" alt="" /> <img src="../images/t60_dev/0024.JPG" alt="" /> <img src="../images/t60_dev/0025.JPG" alt="" /> + </p> + + <p> + Once again, make sure you removed those:<br/> + <img src="../images/t60_dev/0026.JPG" alt="" /> + </p> + + <p> + Remove the shielding containing the motherboard, then flip it over. Remove these screws, placing them on a steady + surface in the same layout as they were in before you removed them. Also, you should mark each screw hole after removing the + screw (a permanent marker pen will do), this is so that you have a point of reference when re-assembling the machine:<br/> + <img src="../images/t60_dev/0027.JPG" alt="" /> <img src="../images/t60_dev/0028.JPG" alt="" /> <img src="../images/t60_dev/0029.JPG" alt="" /> + <img src="../images/t60_dev/0031.JPG" alt="" /> <img src="../images/t60_dev/0032.JPG" alt="" /> <img src="../images/t60_dev/0033.JPG" alt="" /> + </p> + + <p> + Remove microphone (soldering iron not needed. Just wedge it out gently):<br/> + <img src="../images/t60_dev/0039.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 infrared:<br/> + <img src="../images/t60_dev/0040.JPG" alt="" /> <img src="../images/t60_dev/0042.JPG" alt="" /> + </p> + + <p> + Remove cardbus (it's in a socket, no need to disable. Just remove the port itself):<br/> + <img src="../images/t60_dev/0041.JPG" alt="" /><br/> + <b>Rationale:</b><br/> + It has direct memory access and can be used to extract sensitive details (such as LUKS keys). See + 'GoodBIOS' video linked at the end (speaker is Peter Stuge, a coreboot hacker). The video covers X60 + but the same topics apply to T60. + </p> + + <p> + Before re-installing the upper chassis, remove the speaker:<br/> + <img src="../images/t60_dev/0043.JPG" alt="" /> <img src="../images/t60_dev/0044.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 wwan:<br/> + <img src="../images/t60_dev/0045.JPG" alt="" /><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> + + <p> + This is where the simcard connector is soldered. See notes above about wwan. Remove simcard by removing battery + and then it's accessible (so, remember to do this when you re-assemble. or you could do it now?)<br/> + <img src="../images/t60_dev/0046.JPG" alt="" /> + </p> + + <p> + Put those screws back:<br/> + <img src="../images/t60_dev/0047.JPG" alt="" /> + </p> + + <p> + Put it back into lower chassis:<br/> + <img src="../images/t60_dev/0048.JPG" alt="" /> + </p> + + <p> + Attach LCD and insert screws (also, attach the lcd cable to the board):<br/> + <img src="../images/t60_dev/0049.JPG" alt="" /> + </p> + + <p> + Insert those screws:<br/> + <img src="../images/t60_dev/0050.JPG" alt="" /> + </p> + + <p> + On the CPU (and there is another chip south-east to it, sorry forgot to take pic) + clean off the old thermal paste (rubbing a1ocheal (misspelling intentional. halal internet)) and apply new (Artic Silver 5 is good, others are good too) + you should also clean the heatsink the same way<br/> + <img src="../images/t60_dev/0051.JPG" alt="" /> + </p> + + <p> + Attach the heatsink and install the screws (also, make sure to install the AC jack as highlighted):<br/> + <img src="../images/t60_dev/0052.JPG" alt="" /> + </p> + + <p> + Reinstall that upper bezel:<br/> + <img src="../images/t60_dev/0053.JPG" alt="" /> + </p> + + <p> + Do that:<br/> + <img src="../images/t60_dev/0054.JPG" alt="" /> <img src="../images/t60_dev/0055.JPG" alt="" /> + </p> + + <p> + Attach keyboard and install nvram battery:<br/> + <img src="../images/t60_dev/0056.JPG" alt="" /> <img src="../images/t60_dev/0057.JPG" alt="" /> + </p> + + <p> + Place keyboard and (sorry, forgot to take pics) reinstall the palmrest and insert screws on the underside:<br/> + <img src="../images/t60_dev/0058.JPG" alt="" /> + </p> + + <p> + Remove those covers and unscrew:<br/> + <img src="../images/t60_dev/0059.JPG" alt="" /> <img src="../images/t60_dev/0060.JPG" alt="" /> <img src="../images/t60_dev/0061.JPG" alt="" /> + </p> + + <p> + Gently pry off the front bezel (sorry, forgot to take pics). + </p> + + <p> + Remove bluetooth module:<br/> + <img src="../images/t60_dev/0062.JPG" alt="" /> <img src="../images/t60_dev/0063.JPG" alt="" /> + </p> + + <p> + Re-attach the front bezel and re-insert the screws (sorry, forgot to take pics). + </p> + + <p> + It lives!<br/> + <img src="../images/t60_dev/0071.JPG" alt="" /> <img src="../images/t60_dev/0072.JPG" alt="" /> <img src="../images/t60_dev/0073.JPG" alt="" /> + </p> + + <p> + Always stress test ('stress -c 2' and xsensors. below 90C is ok) when replacing cpu paste/heatsink:<br/> + <img src="../images/t60_dev/0074.JPG" alt="" /> + </p> + + <h2> + Not covered yet: + </h2> + <ul> + <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>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> + 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> + <p> + <a href="http://www.coreboot.org/Intel_82573_Ethernet_controller">Intel 82573 Ethernet controller</a> + on the X60 seems safe, according to Denis. + </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 guide on software security.</li> + </ul> + + <h1> + Further reading material (software security) + </h1> + <ul> + <li><a href="../gnulinux/encrypted_trisquel.html">Installing Trisquel GNU/Linux with full disk encryption (including /boot)</a></li> + <li><a href="../gnulinux/encrypted_parabola.html">Installing Parabola GNU/Linux with full disk encryption (including /boot)</a></li> + <li><a href="dock.html">Notes about DMA access and the docking station</a></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 <info@gluglug.org.uk><br/> + This document is released under the Creative Commons Attribution-ShareAlike 4.0 International Public License and all future versions. + A copy of the license can be found at <a href="../license.txt">../license.txt</a>. + </p> + + <p> + This document is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See <a href="../license.txt">../license.txt</a> for more information. + </p> + +</body> +</html> diff --git a/docs/security/x60_security.html b/docs/security/x60_security.html new file mode 100644 index 0000000..33ccb6d --- /dev/null +++ b/docs/security/x60_security.html @@ -0,0 +1,301 @@ +<!DOCTYPE html> +<html> +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1"> + + <style type="text/css"> + @import url('../css/main.css'); + </style> + + <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="../images/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="../images/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="../images/x60_security/0000_simcard0.jpg" alt="" /><br/> + SIM card (not present in the picture) is in the marked location:<br/> + <img src="../images/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="../images/x60_security/0000.jpg" alt="" /> + </p> + <p> + Push the keyboard forward (carefully):<br/> + <img src="../images/x60_security/0001.jpg" alt="" /> + </p> + <p> + Lift the keyboard up and disconnect it from the board:<br/> + <img src="../images/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="../images/x60_security/0003.jpg" alt="" /> + </p> + <p> + You should now have this:<br/> + <img src="../images/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="../images/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="../images/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="../images/x60_security/0001_modem.jpg" alt="" /><br/> + (useless, obsolete device) + </p> + + <p> + Remove the speaker:<br/> + <img src="../images/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="../images/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> + 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> + <p> + <a href="http://www.coreboot.org/Intel_82573_Ethernet_controller">Intel 82573 Ethernet controller</a> + on the X60 seems safe, according to Denis. + </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 guide on software security.</li> + </ul> + + <h1> + Further reading material (software security) + </h1> + <ul> + <li><a href="../gnulinux/encrypted_trisquel.html">Installing Trisquel GNU/Linux with full disk encryption (including /boot)</a></li> + <li><a href="../gnulinux/encrypted_parabola.html">Installing Parabola GNU/Linux with full disk encryption (including /boot)</a></li> + <li><a href="dock.html">Notes about DMA access and the docking station</a></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 <info@gluglug.org.uk><br/> + This document is released under the Creative Commons Attribution-ShareAlike 4.0 International Public License and all future versions. + A copy of the license can be found at <a href="../license.txt">../license.txt</a>. + </p> + + <p> + This document is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See <a href="../license.txt">../license.txt</a> for more information. + </p> + +</body> +</html> |