From 2a73d63b75589f652cca669bfac7fe95e8405467 Mon Sep 17 00:00:00 2001
From: Francis Rowe <info@gluglug.org.uk>
Date: Mon, 15 Sep 2014 00:05:46 -0400
Subject: Documentation: add tutorial for encrypted Parabola GNU/Linux installation.
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+<!DOCTYPE html>
+<html>
+<head>
+ <meta charset="utf-8">
+ <meta name="viewport" content="width=device-width, initial-scale=1">
+
+ <style type="text/css">
+ body {
+ background:#fff;
+ color:#000;
+ font-family:sans-serif;
+ font-size:1em;
+ }
+ div.important {
+ background-color:#ccc;
+ }
+ </style>
+
+ <title>Installing Parabola GNU/Linux with full disk encryption (including /boot)</title>
+</head>
+
+<body>
+ <header>
+ <h1>Installing Parabola GNU/Linux with full disk encryption (including /boot)</h1>
+ <aside>Or <a href="../index.html">back to main index</a></aside>
+ </header>
+
+ <p>
+ Because GRUB is installed directly as a payload of libreboot (or coreboot), you don't need an unencrypted /boot partition
+ when setting up an encrypted system. This means that your machine can really secure data while powered off.
+ </p>
+
+ <p>
+ Boot Parabola's install environment. <a href="grub_boot_installer.html">How to boot a GNU/Linux installer</a>.
+ </p>
+
+ <p>
+ Parabola is much more flexible than Trisquel, but also more involved to setup. Use Parabola. It's 10 million times better than Trisquel.
+ </p>
+
+ <p>
+ Firstly if you use an SSD, beware there are issues with TRIM (not enabled through luks) and security issues if you do enable it.
+ See <a href="https://wiki.archlinux.org/index.php/Dm-crypt/Specialties#Discard.2FTRIM_support_for_solid_state_drives_.28SSD.29">this page</a>
+ for more info.
+ </p>
+
+ <p>
+ Wipe the MBR (if you use MBR):<br/>
+ # <b>lsblk</b><br/>
+ Your HDD is probably /dev/sda:
+ # <b>dd if=/dev/zero of=/dev/sda bs=446 count=1</b><br/>
+ Never use SeaBIOS! The MBR section can easily be changed with malicious code, which SeaBIOS will blindly execute.
+ This guide is for libreboot with GRUB-as-payload only.
+ </p>
+
+ <p>
+ Securely wipe the drive:<br/>
+ # <b>dd if=/dev/urandom of=/dev/sda</b>
+ </p>
+
+ <p>
+ This guide will go through the installation steps taken at the time of writing, which may or may not change due to
+ the volatile nature of Parabola (it changes all the time). In general most of it should remain the same. If you spot mistakes,
+ please say so! This guide will be ported to the Parabola wiki at a later date. For up to date Parabola install guide, go to
+ the Parabola wiki. This guide essentially cherry picks the useful information (valid at the time of writing: 2014-09-15).
+ </p>
+
+ <h2>
+ Change keyboard layout
+ </h2>
+ <p>
+ Parabola live shell assumes US Qwerty. If you have something different, use:<br/>
+ # <b>loadkeys LAYOUT</b><br/>
+ For me, LAYOUT would have been dvorak-uk.
+ </p>
+
+ <h2>Getting started</h2>
+ <p>
+ The beginning is based on <a href="https://wiki.parabolagnulinux.org/Installation_Guide">https://wiki.parabolagnulinux.org/Installation_Guide</a>.
+ Then I referred to <a href="https://wiki.archlinux.org/index.php/Partitioning">https://wiki.archlinux.org/index.php/Partitioning</a> at first.
+ </p>
+
+ <h2>dm-mod</h2>
+ <p>
+ device-mapper will be used - a lot. Make sure that the kernel module is loaded:<br/>
+ # <b>modprobe dm-mod</b>
+ </p>
+
+ <h2>Create LUKS partition</h2>
+ <p>
+ I am using MBR partitioning, so I use cfdisk:<br/>
+ # <b>cfdisk /dev/sda</b>
+ </p>
+ <p>
+ I create a single large sda1 filling the whole drive, leaving it as the default type 'Linux' (83).
+ </p>
+ <p>
+ Now I refer to <a href="https://wiki.archlinux.org/index.php/Dm-crypt/Drive_preparation#Partitioning">https://wiki.archlinux.org/index.php/Dm-crypt/Drive_preparation#Partitioning</a>:<br/>
+ I am then directed to <a href="https://wiki.archlinux.org/index.php/Dm-crypt/Device_encryption">https://wiki.archlinux.org/index.php/Dm-crypt/Device_encryption</a>.
+ </p>
+ <p>
+ Parabola forces you to RTFM.
+ </p>
+ <p>
+ It tells me to run:<br/>
+ # <b>cryptosetup benchmark</b> (for making sure the list below is populated)<br/>
+ Then:<br/>
+ # <b>cat /proc/crypto</b><br/>
+ This gives me crypto options that I can use. It also provides a representation of the best way to setup LUKS (in this case, security is a priority; speed, a distant second).
+ To gain a better understanding, I am also reading:<br/>
+ # <b>man cryptsetup</b>
+ </p>
+ <p>
+ Following that page, based on my requirements, I do the following based on
+ based on <a href="https://wiki.archlinux.org/index.php/Dm-crypt/Device_encryption#Encryption_options_for_LUKS_mode">https://wiki.archlinux.org/index.php/Dm-crypt/Device_encryption#Encryption_options_for_LUKS_mode</a>.
+ Reading through, it seems like Serpent (encryption) and Whirlpool (hash) is the best option.
+ </p>
+ <p>
+ I am initializing LUKS with the following:<br/>
+ # <b>cryptsetup -v --cipher serpent-xts-plain64 --key-size 512 --hash whirlpool --use-random --verify-passphrase luksFormat /dev/sda1</b>
+ -- choose a <b>secure</b> passphrase here. Ideally lots of lowercase/uppercase numbers, letters, symbols etc all in a random pattern. The password
+ length should be as long as you are able to handle without writing it down or storing it anywhere. Ideally, 100 characters or more.
+ It might take you a while to memorize a long passphrase before beginning this step.
+ </p>
+
+ <h2>Create LVM</h2>
+ <p>
+ Now I refer to <a href="https://wiki.archlinux.org/index.php/LVM">https://wiki.archlinux.org/index.php/LVM</a>.
+ </p>
+ <p>
+ Open the LUKS partition:<br/>
+ # <b>cryptsetup open --type luks /dev/sda1 lvm</b> (it will be available at /dev/mapper/lvm)
+ </p>
+ <p>
+ Create LVM partition:<br/>
+ # <b>pvcreate /dev/mapper/lvm</b><br/>
+ Show that you just created it:<br/>
+ # <b>pvdisplay</b>
+ </p>
+ <p>
+ Now I create the volume group, inside of which the logical volumes will be created:<br/>
+ # <b>vgcreate matrix /dev/mapper/lvm</b> (volume group name is 'matrix')<br/>
+ Show that you created it:<br/>
+ # <b>vgdisplay</b>
+ </p>
+ <p>
+ Now create the logical volumes:<br/>
+ # <b>lvcreate -L 2G matrix -n swapvol</b> (2G swap partition, named <u>swapvol</u>)<br/>
+ # <b>lvcreate -l +100%FREE matrix -n rootvol</b> (single large partition in the rest of the space, named <u>rootvol</u>)<br/>
+ You can also be flexible here, for example you can specify a /boot, a /, a /home, a /var, a /usr, etc. For example,
+ if you will be running a web/mail server then you want /var in it's own partition (so that if it fills up with logs, it won't crash your system).
+ For a home/laptop system (typical use case), a root and a swap will do (really).
+ </p>
+ <p>
+ Verify that the logical volumes were created, using the following command:<br/>
+ # <b>lvdisplay</b>
+ </p>
+
+ <h2>Create / and swap partitions</h2>
+ <p>
+ For the swapvol LV I use:<br/>
+ # <b>mkswap /dev/mapper/matrix-swapvol</b>
+ </p>
+ <p>
+ For the rootvol LV I use:<br/>
+ # <b>mkfs.ext4 /dev/mapper/matrix-rootvol</b>
+ </p>
+
+ <h2>Continue with Parabola installation</h2>
+ <p>
+ Mount the root (/) partition:<br/>
+ # <b>mount /dev/matrix/rootvol /mnt</b><br/>
+ </p>
+ <p>
+ This guide is really about GRUB, Parabola and cryptomount. I have to show how to install Parabola
+ so that the guide can continue.
+ </p>
+ <p>
+ Now I am following the rest of <a href="https://wiki.parabolagnulinux.org/Installation_Guide">https://wiki.parabolagnulinux.org/Installation_Guide</a>.
+ I also also cross referencing <a href="https://wiki.archlinux.org/index.php/Installation_guide">https://wiki.archlinux.org/index.php/Installation_guide</a>.
+ </p>
+ <p>
+ Create /home and /boot on rootvol mountpoint:<br/>
+ # <b>mkdir /mnt/home</b><br/>
+ # <b>mkdir /mnt/boot</b>
+ </p>
+ <p>
+ The wiki says to enable the swap so that it can be detected by 'genfstab':<br/>
+ # <b>swapon /dev/matrix/swapvol</b>
+ </p>
+ <p>
+ DHCP was already working for me, so I had internet during the install. Therefore, I ignore the 'Connect to the Internet' section of the install guide.
+ I also ignore wifi, since I can set that up after the install. For now, I am just using ethernet.
+ Otherwise, refer to <a href="https://wiki.archlinux.org/index.php/Configuring_Network">https://wiki.archlinux.org/index.php/Configuring_Network</a>.
+ You can test to see if internet is already working by pinging a few domains.
+ </p>
+ <p>
+ The following is based on 'Verification of package signatures' in the Parabola install guide. Check there first to see if steps differ by now.
+ Now you have to update the default Parabola keyring. This is used for signing and verifying packages:<br/>
+ # <b>pacman -Sy parabola-keyring</b><br/>
+ It says that you you get GPG errors, it's probably an expired key so do:<br/>
+ # <b>pacman-key --populate parabola</b><br/>
+ # <b>pacman-key --refresh-keys</b><br/>
+ # <b>pacman -Sy parabola-keyring</b><br/>
+ To be honest, you should do the above anyway. Parabola has a lot of maintainers, and a lot of keys. Really!<br/>
+ Also, it says that if the clock is set incorrectly then you have to manually set the correct time (if keys are listed as expired because of it):<br/>
+ # <b>date MMDDhhmm[[CC]YY][.ss]</b>
+ </p>
+
+ <h3>Install the base system</h3>
+ <p>
+ I commented out all lines except the Server line for the UK Parabola server (main server) in <b>/etc/pacman.d/mirrorlist</b> and then did:<br/>
+ # <b>pacman -Syu</b><br/>
+ I also had to upgrade pacman and then do the above again:<br/>
+ # <b>pacman -Sy pacman</b>
+ </p>
+ <p>
+ I also like to install other packages (base-devel, compilers and so on) and wpa_supplicant/dialog are needed for wireless after the install:<br/>
+ # <b>pacstrap /mnt base base-devel wpa_supplicant dialog</b>
+ </p>
+
+ <h3>Configure the system</h3>
+ <p>
+ From the Parabola installation guide (Arch's one was identical):<br/>
+ # <b>genfstab -p /mnt >> /mnt/etc/fstab</b>
+ </p>
+ <p>
+ Chroot into new system:<br/>
+ # <b>arch-chroot /mnt</b>
+ </p>
+ <p>
+ It's a good idea to have this installed:<br/>
+ # <b>pacman -S linux-libre-lts</b>
+ </p>
+ <p>
+ This is another kernel that sits inside /boot, which you can use. LTS means 'long-term support'. These are so-called 'stable' kernels
+ that can be used as a fallback during updates, if a bad kernel causes issues for you.
+ </p>
+ <p>
+ Parabola does not have wget. This is sinister. Install it:<br/>
+ # <b>pacman -S wget</b>
+ </p>
+ <ul>
+ <li>Write your hostname to /etc/hostname</li>
+ <li>
+ Symlink /etc/localtime to /usr/share/zoneinfo/Zone/SubZone. Replace Zone and Subzone to your liking. For example:
+ <ul>
+ <li># <b>ln -s /usr/share/zoneinfo/Europe/London /etc/localtime</b></li>
+ </ul>
+ </li>
+ <li>
+ Set <a href="https://wiki.parabolagnulinux.org/Locale#Setting_system-wide_locale">locale</a> preferences in /etc/locale.conf. In my case, I did:<br/>
+ <i>
+ LANG="en_GB.UTF-8"<br/>
+ # Keep the default sort order (e.g. files starting with a '.'<br/>
+ # should appear at the start of a directory listing.)<br/>
+ LC_COLLATE="C"<br/>
+ # Set the short date to YYYY-MM-DD (test with "date +%c")<br/>
+ LC_TIME="en_GB.UTF-8"
+ </i>
+ </li>
+ <li>
+ Add <a href="https://wiki.parabolagnulinux.org/KEYMAP">console keymap and font</a> preferences in /etc/vconsole.conf. In my case:<br/>
+ <i>
+ KEYMAP=dvorak-uk<br/>
+ FONT=Lat2-Terminus16
+ </i>
+ </li>
+ <li>
+ Uncomment the selected locale (same as what you specified in /etc/locale.conf) in /etc/locale.gen and generate it with:
+ <ul>
+ <li># <b>locale-gen</b></li>
+ </ul>
+ </li>
+ <li>
+ Configure /etc/mkinitcpio.conf as needed (see <a href="https://wiki.parabolagnulinux.org/Mkinitcpio">mkinitcpio</a>)
+ Specifically, for this use case:<br/>
+ <ul>
+ <li>
+ add <b>i915</b> to the MODULES array (forces the driver to load earlier, so that the consolefont isn't wiped out after getting to login).<br/>
+ add <b>encrypt</b> and <b>lvm2</b> in that order, before the 'filesystems' entry in the HOOKS array.<br/>
+ add <b>keymap</b>, <b>consolefont</b> and <b>shutdown</b> to the end of the HOOKS array in that order.<br/>
+ move <b>keyboard</b>, <b>keymap</b> and <b>consolefont</b> in that order, to go before 'encrypt' in the HOOKS array.<br/>
+ At the end your HOOKS array will look like this:<br/>
+ <i>HOOKS="base udev autodetect modconf block keyboard keymap consolefont encrypt lvm2 filesystems fsck shutdown"</i>
+ <ul>
+ <li>keymap adds to initramfs the keymap that you specified in /etc/vconsole.conf</li>
+ <li>consolefont adds to initramfs the font that you specified in /etc/vconsole.conf</li>
+ <li>encrypt adds LUKS support to the initramfs - needed to unlock your disks at boot time</li>
+ <li>lvm2 adds LVM support to the initramfs - needed to mount the LVM partitions at boot time</li>
+ <li>shutdown is needed according to Parabola wiki for unmounting devices (such as LUKS/LVM) during shutdown</li>
+ <li>
+ Runtime modules can be found in /usr/lib/initcpio/hooks, and build hooks can be found in
+ /usr/lib/initcpio/install.
+ </li>
+ <li><b>mkinitcpio -H hookname</b> gives information about each hook.</li>
+ </ul>
+ </li>
+ </ul>
+ </li>
+ <li>
+ Now using mkinitcpio, you can create the kernel and ramdisk for booting with (note, this is different than Arch, specifying linux-libre instead of linux):<br/>
+ # <b>mkinitcpio -p linux-libre</b><br/>
+ Also do it for linux-libre-lts:<br/>
+ # <b>mkinitcpio -p linux-libre-lts</b>
+ </li>
+ </ul>
+
+ <h3>Set a root password</h3>
+ <p>
+ At the time of writing, Parabola used SHA512 by default for it's password hashing.
+ </p>
+ <p>
+ I referred to <a href="https://wiki.archlinux.org/index.php/SHA_password_hashes">https://wiki.archlinux.org/index.php/SHA_password_hashes</a>.
+ </p>
+ <p>
+ Open /etc/pam.d/passwd and add rounds=65536 at the end of the uncommented 'password' line.
+ </p>
+ <p>
+ # <b>passwd root</b><br/>
+ Make sure to set a secure password! Also, it must never be the same as your LUKS password.
+ </p>
+
+ <h3>Extra security tweaks</h3>
+ <p>
+ Based on <a href="https://wiki.archlinux.org/index.php/Security">https://wiki.archlinux.org/index.php/Security</a>.
+ </p>
+ <p>
+ Restrict access to important directories:<br/>
+ # <b>chmod 700 /boot /etc/{iptables,arptables}</b>
+ </p>
+ <p>
+ Lockout user after three failed login attempts:<br/>
+ Edit the file /etc/pam.d/system-login and comment out that line:<br/>
+ <i># auth required pam_tally.so onerr=succeed file=/var/log/faillog</i><br/>
+ Or just delete it. Above it, put:<br/>
+ <i>auth required pam_tally.so deny=2 unlock_time=600 onerr=succeed file=/var/log/faillog</i><br/>
+ To unlock a user manually (if a password attempt is failed 3 times), do:<br/>
+ # <b>pam_tally --user --reset</b>
+ What the above configuration does is lock the user out for 10 minutes, if they make 3 failed login attempts.
+ </p>
+ <p>
+ Configure sudo - not covered here. Will be covered post-installation in another tutorial, at a later date.
+ If this is a single-user system, you don't really need sudo.
+ </p>
+
+ <h3>Unmount, reboot!</h3>
+ <p>
+ Exit from chroot:<br/>
+ # <b>exit</b>
+ </p>
+ <p>
+ unmount:<br/>
+ # <b>umount /mnt</b><br/>
+ # <b>swapoff -a</b>
+ </p>
+ <p>
+ deactivate the lvm lv's:<br/>
+ # <b>lvchange -an /dev/matrix/rootvol</b><br/>
+ # <b>lvchange -an /dev/matrix/swapvol</b><br/>
+ </p>
+ <p>
+ Lock the encrypted partition (close it):<br/>
+ # <b>cryptsetup luksClose lvm</b>
+ </p>
+ <p>
+ # <b>shutdown -h now</b><br/>
+ Then boot up again.
+ </p>
+
+ <h3>Booting from GRUB</h3>
+ <p>
+ Initially you will have to boot manually. Press C to get to the GRUB command line. The underlined parts are optional
+ (using those 2 underlines will boot lts kernel instead of normal).
+ </p>
+ <p>
+ grub> <b>cryptomount -a (ahci0,msdos1)</b><br/>
+ grub> <b>set root='lvm/matrix-rootvol'</b><br/>
+ grub> <b>linux /boot/vmlinuz-linux-libre<u>-lts</u> root=/dev/matrix/rootvol cryptdevice=/dev/sda1:root</b><br/>
+ grub> <b>initrd /boot/initramfs-linux-libre<u>-lts</u>.img</b><br/>
+ grub> <b>boot</b><br/>
+ </p>
+
+<hr/>
+
+ <h2>Modify grub.cfg inside the ROM</h2>
+
+ <p>
+ Now you need to modify the ROM, so that Parabola can boot automatically with this configuration.
+ <a href="grub_cbfs.html">grub_cbfs.html</a> shows you how. Follow that guide, using the configuration details below.
+ </p>
+ <p>
+ Inside the 'Load Operating System' menu entry, change the contents to:<br/>
+ <b><i>
+ cryptomount -a (ahci0,msdos1)<br/>
+ set root='lvm/matrix-rootvol'<br/>
+ linux /boot/vmlinuz-linux-libre<u>-lts</u> root=/dev/matrix/rootvol cryptdevice=/dev/sda1:root<br/>
+ initrd /boot/initramfs-linux-libre<u>-lts</u>.img
+ </i></b>
+ </p>
+
+ <p>
+ Note: the underlined parts above (-lts) can also be removed, to boot the latest kernel instead of LTS (long-term support) kernels.
+ You could also copy the menu entry and in one have -lts, and without in the other menuentry.
+ </p>
+
+ <p>
+ Above the 'Load Operating System' menu entry you should also add a GRUB password, like so:
+ </p>
+<pre><b><i>set superusers="root"
+password_pbkdf2 root grub.pbkdf2.sha512.10000.711F186347156BC105CD83A2ED7AF1EB971AA2B1EB2640172F34B0DEFFC97E654AF48E5F0C3B7622502B76458DA494270CC0EA6504411D676E6752FD1651E749.8DD11178EB8D1F633308FD8FCC64D0B243F949B9B99CCEADE2ECA11657A757D22025986B0FA116F1D5191E0A22677674C994EDBFADE62240E9D161688266A711
+</i></b></pre>
+
+ <p>
+ Note that the above entry specifies user 'root'; this is just a username for GRUB. You don't even need to use root.
+ Change root on both of those 2 lines to whatever you want.
+ </p>
+
+ <p>
+ Start dhcp on ethernet:<br/>
+ # <b>systemctl start dhcpcd.service</b>
+ This is just for the step below. I won't cover network configuration here. That is for another Parabola article.
+ </p>
+
+ <p>
+ The password hash (it's <b>password</b>, by the way) after <i>'password_pbkdf2 root'</i> <i>should be changed</i> and is created by the <b>grub-mkpasswd-pbkdf2</b> utility, which you need to install or otherwise compile,
+ like so:<br/>
+ # <b>pacman -S grub</b>
+ </p>
+
+ <p>
+ GRUB isn't needed for booting, since it's already included as a payload in libreboot. This is only so that the utility needed becomes available. Get your hash
+ by entering your chosen password at the prompt, when running this command:<br/>
+ # <b>grub-mkpasswd-pbkdf2</b>
+ </p>
+
+ <p>
+ It will output the hash for the password that you entered. Make sure to specify a password that is different from both your LUKS *and* your root/user password.
+ Use it to replace the default hash mentioned above.
+ </p>
+
+ <p>
+ With this setup, you will have to enter a password at boot time, in GRUB, before being able to use any of the menu entries or switch to the terminal.
+ This protects your system from an attacker simply booting a live usb distro and re-flashing the boot firmware.
+ </p>
+
+ <p>
+ You probably only need base-devel (compilers and so on) to build and use cbfstool. It was already installed if you followed this tutorial, but here it is:<br/>
+ # <b>pacman -S base-devel</b>
+ </p>
+
+ <p>
+ For flashing the modified ROM, I just used flashrom from the Parabola repo's:<br/>
+ # <b>pacman -S flashrom</b><br/>
+ I also installed dmidecode:<br/>
+ # <b>pacman -S dmidecode</b>
+ </p>
+
+<hr/>
+
+ <p>
+ If you followed all that correctly, you should now have a fully encrypted Parabola installation.
+ This is a very barebones Parabola install (the default one). Refer to the wiki for how to do the rest
+ (desktop, etc).
+ </p>
+
+<hr/>
+
+ <h2>Further security tips</h2>
+ <p>
+ <a href="https://wiki.archlinux.org/index.php/Security">https://wiki.archlinux.org/index.php/Security</a>.<br/>
+ <a href="https://wiki.parabolagnulinux.org/User:GNUtoo/laptop">https://wiki.parabolagnulinux.org/User:GNUtoo/laptop</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/index.html b/docs/index.html
index bd7c72f..7551179 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -97,7 +97,8 @@
<ul>
<li><a href="howtos/x60_security.html">ThinkPad X60/X60S: hardware security</a></li>
<li><a href="howtos/t60_security.html">ThinkPad T60: hardware security</a></li>
- <li><a href="howtos/encrypted_trisquel.html">Installing Trisquel GNU/Linux with full disk encryption (including /boot)</a></li>
+ <li><a href="howtos/encrypted_parabola.html">Installing Parabola GNU/Linux-libre with full disk encryption (including /boot)</a></li>
+ <li><a href="howtos/encrypted_trisquel.html">Installing Trisquel GNU/Linux-libre with full disk encryption (including /boot)</a></li>
</ul>
<h2>Hardware maintenance</h2>
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