nixpkgs/modules/system/boot/luksroot.nix
Lluís Batlle i Rossell 79d4b11aeb Making the luks thing of initrd a bit more flexible. I used it to get a
ciphered swap, where I could hibernate ciphered.


svn path=/nixos/trunk/; revision=32754
2012-03-03 16:07:18 +00:00

74 lines
2 KiB
Nix

{pkgs, config, ...}:
with pkgs.lib;
let
luks = config.boot.initrd.luks;
openCommand = { name, device }: ''
# Wait for luksRoot to appear, e.g. if on a usb drive.
# XXX: copied and adapted from stage-1-init.sh - should be
# available as a function.
if ! test -e ${device}; then
echo -n "waiting 10 seconds for device ${device} to appear..."
for ((try = 0; try < 10; try++)); do
sleep 1
if test -e ${device}; then break; fi
echo -n "OK"
done
echo "ok"
fi
# open luksRoot and scan for logical volumes
cryptsetup luksOpen ${device} ${name}
'';
in
{
options = {
boot.initrd.luks.enable = mkOption {
default = false;
description = '';
Have luks in the initrd.
'';
};
boot.initrd.luks.devices = mkOption {
default = [ ];
example = [ { name = "luksroot"; device = "/dev/sda3"; } ];
description = '';
The list of devices that should be decrypted using LUKS before trying to mount the
root partition. This works for both LVM-over-LUKS and LUKS-over-LVM setups.
The devices are decrypted to the device mapper names defined.
Make sure that initrd has the crypto modules needed for decryption.
'';
};
};
config = mkIf luks.enable {
# Some modules that may be needed for mounting anything ciphered
boot.initrd.kernelModules = [ "aes_generic" "aes_x86_64" "dm_mod" "dm_crypt"
"sha256_generic" "cbc" "cryptd" ];
# copy the cryptsetup binary and it's dependencies
boot.initrd.extraUtilsCommands = ''
cp -pdv ${pkgs.cryptsetup}/sbin/cryptsetup $out/bin
# XXX: do we have a function that does this?
for lib in $(ldd $out/bin/cryptsetup |grep '=>' |grep /nix/store/ |cut -d' ' -f3); do
cp -pdvn $lib $out/lib
cp -pvn $(readlink -f $lib) $out/lib
done
'';
boot.initrd.extraUtilsCommandsTest = ''
$out/bin/cryptsetup --version
'';
boot.initrd.preLVMCommands = concatMapStrings openCommand luks.devices;
};
}