mirror of
https://github.com/ItsDrike/nixdots
synced 2024-11-10 02:49:41 +00:00
111 lines
4.1 KiB
Nix
111 lines
4.1 KiB
Nix
{ config, pkgs, ... }:
|
|
let
|
|
impermanence = builtins.fetchTarball "https://github.com/nix-community/impermanence/archive/master.tar.gz";
|
|
in
|
|
{
|
|
imports = [ "${impermanence}/nixos.nix" ];
|
|
|
|
users = {
|
|
# This option makes it that users are not mutable outside our configuration
|
|
# If you are using impermanence, this will actually be the case regardless of this setting,
|
|
# however, setting this explicitly is a good idea, because nix will warn us if
|
|
# our users don't have passwords set
|
|
mutableUsers = false;
|
|
|
|
# Each existing user needs to have a password file defined here
|
|
# otherwise, they will not be available to login.
|
|
# These password files can be generated using the following command:
|
|
# mkpasswd -m sha-512 > /persist/system/passwords/myuser
|
|
users = {
|
|
root = {
|
|
# password file needs to be in a volume marked `neededForRoot = true`
|
|
hashedPasswordFile = "/persist/passwords/root";
|
|
};
|
|
itsdrike = {
|
|
hashedPasswordFile = "/persist/passwords/itsdrike";
|
|
};
|
|
};
|
|
};
|
|
|
|
# Some people use /nix/persist/system instead, leaving the persistent files in /nix subvolume
|
|
# I much prefer using a standalone subvolume for this though.
|
|
environment.persistence."/persist/system" = {
|
|
hideMounts = true;
|
|
directories = [
|
|
"/etc/nixos" # nixos configuration source
|
|
"/etc/NetworkManager/system-connections" # saved network connections
|
|
"/var/db/sudo" # keeps track of who got the sudo lecture already
|
|
"/var/lib/systemd/coredump" # recorded coredumps
|
|
];
|
|
files = [
|
|
"/etc/machine-id"
|
|
|
|
# ssh stuff
|
|
"/etc/ssh/ssh_host_ed25519_key"
|
|
"/etc/ssh/ssh_host_ed25519_key.pub"
|
|
"/etc/ssh/ssh_host_rsa_key"
|
|
"/etc/ssh/ssh_host_rsa_key.pub"
|
|
];
|
|
};
|
|
|
|
# For some reason, NetworkManager needs this instead of the impermanence mode to not get screwed up
|
|
systemd.tmpfiles.rules = [
|
|
"L /var/lib/NetworkManager/secret_key - - - - /persist/system/var/lib/NetworkManager/secret_key"
|
|
"L /var/lib/NetworkManager/seen-bssids - - - - /persist/system/var/lib/NetworkManager/seen-bssids"
|
|
"L /var/lib/NetworkManager/timestamps - - - - /persist/system/var/lib/NetworkManager/timestamps"
|
|
];
|
|
|
|
boot.initrd.systemd = {
|
|
enable = true; # This enables systemd support in stage 1 - required for below setup
|
|
services.rollback = {
|
|
description = "Rollback BTRFS root subvolume to a pristine state";
|
|
wantedBy = [ "initrd.target" ];
|
|
# make sure it's done after decryption (i.e. LUKS/TPM process)
|
|
after = [ "systemd-cryptsetup@cryptfs.service" ];
|
|
# mount the root fs before clearing
|
|
before = [ "sysroot.mount" ];
|
|
unitConfig.DefaultDependencies = "no";
|
|
serviceConfig.Type = "oneshot";
|
|
script = ''
|
|
mkdir -p /mnt
|
|
|
|
# We first mount the btrfs root to /mnt
|
|
# so we can manipulate btrfs subvolumes.
|
|
mount /dev/mapper/cryptfs /mnt
|
|
|
|
# While we're tempted to just delete /root and create
|
|
# a new snapshot from /root-blank, /root is already
|
|
# populated at this point with a number of subvolumes,
|
|
# which makes `btrfs subvolume delete` fail.
|
|
# So, we remove them first.
|
|
#
|
|
# /root contains subvolumes:
|
|
# - /root/var/lib/portables
|
|
# - /root/var/lib/machines
|
|
#
|
|
# These are probably related to systemd-nspawn, but
|
|
# since I don't use it, I'm not 100% sure.
|
|
# Anyhow, deleting these subvolumes hasn't resulted in
|
|
# any issues so far, except for fairly benign-looking
|
|
# errors from systemd-tmpfiles.
|
|
btrfs subvolume list -o /mnt/root |
|
|
cut -f9 -d' ' |
|
|
while read subvolume; do
|
|
echo "deleting /$subvolume subvolume..."
|
|
btrfs subvolume delete "/mnt/$subvolume"
|
|
done &&
|
|
echo "deleting /root subvolume..." &&
|
|
btrfs subvolume delete /mnt/root
|
|
|
|
echo "restoring blank /root subvolume..."
|
|
btrfs subvolume snapshot /mnt/root-blank /mnt/root
|
|
|
|
# Once we're done rolling back to a blank snapshot,
|
|
# we can unmount /mnt and continue on the boot process.
|
|
umount /mnt
|
|
'';
|
|
};
|
|
};
|
|
}
|
|
|