nixfiles/modules/nixos/encryptedDrive.nix

134 lines
3.7 KiB
Nix

{
self,
config,
pkgs,
lib,
...
}: let
inherit (lib.modules) mkIf mkBefore;
inherit (lib.options) mkOption mkEnableOption;
inherit (lib) types;
encryptedUSB = import "${self}/data/drives/encryptedUSB.nix";
driveData = import "${self}/data/drives/encryptedDrive.nix";
cfg = config.boot.encryptedDrive;
in {
options.boot.encryptedDrive = {
enable = mkEnableOption "encrypted drive support for servers and other devices";
mode = mkOption {
type = types.enum [
"encrypted-usb"
"password"
];
default = "encrypted-usb";
};
allowPasswordDecrypt = mkOption {
description = "allow fallback to decrypting with a password when using USB based auth, pass cryptsetup_password to kernel cmdline to switch to password input mode";
type = types.bool;
default = true;
};
};
config = mkIf cfg.enable {
boot = {
initrd.availableKernelModules = [
# For USB w/ Encryption Key
"usb_storage"
"usbcore"
"uas"
"rtsx_pci_sdmmc"
# For USB Keyboards
"usbhid"
"hid_generic"
# For Cryptography
"aesni_intel"
"cryptd"
"crypto_simd"
];
initrd.postDeviceCommands = mkIf (cfg.mode == "encrypted-usb") (mkBefore ''
mkdir -m 0755 -p /keys
mkdir -m 0755 -p ${encryptedUSB.mountpoint}
${
if config.boot.plymouth.enable
then "${pkgs.plymouth}/bin/plymouth hide-splash"
else ""
}
${
if cfg.allowPasswordDecrypt
then ''
if grep "cryptsetup_password" /proc/cmdline; then
USE_PASSWORD_FALLBACK=true
else
USE_PASSWORD_FALLBACK=false
fi
''
else ''
USE_PASSWORD_FALLBACK=false
''
}
while !(test -b ${encryptedUSB.encryptedPath}) && [ "$USE_PASSWORD_FALLBACK" == "false" ]
do
echo "Please Plug In USB"
sleep 1
done
if [ "$USE_PASSWORD_FALLBACK" == "true" ]; then
echo "Please Decrypt Drive"
cryptsetup open ${driveData.encryptedPath} ${driveData.mapperName}
else
echo "Please Decrypt USB"
cryptsetup open ${encryptedUSB.encryptedPath} ${encryptedUSB.preBootMapperName}
fi
if [ "$USE_PASSWORD_FALLBACK" == "false" ]; then
mount -n -t ${encryptedUSB.unencryptedFSType} -o ro ${encryptedUSB.preBootMapperPath} ${encryptedUSB.mountpoint}
cp ${encryptedUSB.encryptionKeysPath}/${config.networking.hostName}.key /keys
chmod 0755 /keys/${config.networking.hostName}.key
umount -f ${encryptedUSB.mountpoint}
cryptsetup close ${encryptedUSB.preBootMapperName}
else
touch /keys/${config.networking.hostName}.key
fi
${
if config.boot.plymouth.enable
then "${pkgs.plymouth}/bin/plymouth show-splash"
else ""
}
'');
initrd.luks.devices = {
"${driveData.mapperName}" = {
device = "${driveData.encryptedPath}";
keyFile =
if cfg.mode == "encrypted-usb"
then "/keys/${config.networking.hostName}.key"
else null;
preLVM = false;
allowDiscards = true;
# Allows decrypting with a password when key is existant on USB but invalid
fallbackToPassword = cfg.allowPasswordDecrypt;
};
};
};
fileSystems = {
"/" = {
device = "${driveData.decryptedPath}";
fsType = "${driveData.unencryptedFSType}";
};
"/boot" = {
device = "${driveData.bootPath}";
fsType = "${driveData.bootFSType}";
};
};
};
}