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+Achieving a Colemak Layout for Typing LUKS Passphrases in Early Boot
+====================================================================
+
+:date: 2019-03-26 14:02
+:category: System Administration
+:tags: cryptsetup, system administration, full disk encryption
+:authors: Maximilian Friedersdorff
+:summary: Having to type passphrases with an unfamiliar keyboard layout is slow and frustrating. 
+
+I use full disk encryption using `LVM on LUKS`_ on all of my desktops and
+laptops. I trust my memory more than I do any USB device and so I rely on
+typing in a passphrase during the boot process. Doing so is tedious, because in
+general my prefered keyboard layout (Colemak) is not available before the root
+partition has been mounted. The correct solution is to include the Colemak
+keyboard layout as part of the initramfs.
+
+Instead I propose the following hack:  Add a passphrase to the LUKS container
+such that it is correct when one types the normal passphrase on the unfamiliar
+keyboard layout, in my case those layouts are Colemak and QWERTY. First let's
+define some terms:
+
+- Layout1-Layout2 Conjugate: The Layout1-Layout2 Conjugate of the string `s` is
+  the string that would result from typing `s` as if one is using a Layout1
+  keyboard, but while actually typing on a Layout2 keyboard.  The Colemak-QWERTY
+  Conjugate of the string 'correct' is 'c;sskcf'.  Similarly, the
+  QWERTY-Colemak Conjugate of the string 'correct' is 'cyppfcg'.  Importantly
+  the inverse operation of the Layout1-Layout2 Conjugate is the Layout2-Layout1
+  Conjugate.  For example, the QWERTY-Colemak Conjugate of 'c;sskcf' is
+  'correct'.
+
+In my case, I have to type my passphrase on a QWERTY keyboard during the early
+boot process, but I want to type it as if I am typing on a Colemak keyboard.
+This will result in the Colemak-QWERTY Conjugate as defined above.  If my
+passphrase is 'correct horse battery staple', I will produce the string
+'c;sskcf h;sdk baffkso dfaruk' in this manner.  In order for this to correctly
+unlock my LUKS container, I should set this as an additional passphrase.
+
+
+.. _LVM on LUKS: https://wiki.archlinux.org/index.php/Dm-crypt/Encrypting_an_Entire_System#LVM_on_LUKS
+