dotfiles/hosts/i001/hardware-mounts.nix
2025-12-16 00:37:09 -06:00

284 lines
8.3 KiB
Nix

{
config,
utils,
pkgs,
lib,
...
}:
let
USB_KEY = "/dev/disk/by-uuid/63a7bd87-d644-43ea-83ba-547c03012fb6";
BOOT = "/dev/disk/by-uuid/ABDB-2A38";
PRIMARY_UUID = "08610781-26d3-456f-9026-35dd4a40846f";
PRIMARY = "/dev/disk/by-uuid/${PRIMARY_UUID}";
inherit (utils) escapeSystemdPath;
primaryDeviceUnit = "${escapeSystemdPath PRIMARY}.device";
in
lib.mkMerge [
# Main filesystems
{
# BOOT
fileSystems."/boot" = {
device = BOOT;
fsType = "vfat";
options = [
"fmask=0022"
"dmask=0022"
];
};
# PRIMARY
fileSystems."/" = {
device = PRIMARY;
fsType = "bcachefs";
options = [
"X-mount.subdir=@root"
];
};
fileSystems."/.old_roots" = {
device = PRIMARY;
fsType = "bcachefs";
options = [
"nofail" # this may not exist yet just skip it
"X-mount.mkdir"
"X-mount.subdir=@old_roots"
];
};
fileSystems."/nix" = {
device = PRIMARY;
fsType = "bcachefs";
options = [
"X-mount.mkdir"
"X-mount.subdir=@nix"
"relatime"
];
};
fileSystems."/.snapshots" = {
device = PRIMARY;
fsType = "bcachefs";
options = [
"X-mount.mkdir"
"X-mount.subdir=@root"
"relatime"
];
};
# (optional) for preservation/impermanence
fileSystems."/persist" = {
device = PRIMARY;
fsType = "bcachefs";
options = [
"X-mount.mkdir"
"X-mount.subdir=@persist"
];
};
}
# SWAP
{
swapDevices = [
# {
# device = "/.swap/swapfile";
# size = 8 * 1024; # Creates an 8GB swap file
# }
];
}
# Disable bcachefs built in password prompts for all mounts (which asks for every single subdir mount above
(
let
disableFs = fs: {
name = "unlock-bcachefs-${utils.escapeSystemdPath fs.mountPoint}";
value = {
enable = false;
};
};
in
{
boot.initrd.systemd.enable = true;
# https://github.com/NixOS/nixpkgs/blob/6cdf2f456a57164282ede1c97fc5532d9dba1ee0/nixos/modules/tasks/filesystems/bcachefs.nix#L254-L259
systemd.services =
let
isSystemdNonBootBcache = fs: (fs.fsType == "bcachefs") && (!utils.fsNeededForBoot fs);
bcacheNonBoots = lib.filterAttrs (k: fs: isSystemdNonBootBcache fs) config.fileSystems;
in
(lib.mapAttrs' (k: disableFs) bcacheNonBoots);
# The above auto generates these...
# {
# "unlock-bcachefs-${escapeSystemdPath "/.old_roots"}".enable = false;
# "unlock-bcachefs-${escapeSystemdPath "/.snapshots"}".enable = false;
# "unlock-bcachefs-${escapeSystemdPath "/.swap"}".enable = false;
# "unlock-bcachefs-${escapeSystemdPath "/persist"}".enable = false;
# };
# https://github.com/NixOS/nixpkgs/blob/6cdf2f456a57164282ede1c97fc5532d9dba1ee0/nixos/modules/tasks/filesystems/bcachefs.nix#L291
boot.initrd.systemd.services =
let
isSystemdBootBcache = fs: (fs.fsType == "bcachefs") && (utils.fsNeededForBoot fs);
bcacheBoots = lib.filterAttrs (k: fs: isSystemdBootBcache fs) config.fileSystems;
in
(lib.mapAttrs' (k: disableFs) bcacheBoots);
# same with that above
# {
# "unlock-bcachefs-${escapeSystemdPath "/sysroot"}".enable = false;
# "unlock-bcachefs-${escapeSystemdPath "/"}".enable = false;
# "unlock-bcachefs-${escapeSystemdPath "/nix"}".enable = false;
# };
}
)
# Bcachefs auto decryption
{
boot.supportedFilesystems = [
"bcachefs"
];
boot.initrd.systemd.mounts = [
{
what = USB_KEY;
type = "bcachefs";
where = "/usb_key";
options = "ro";
description = "key";
wantedBy = [
"initrd.target"
"initrd-root-fs.target"
];
}
];
boot.initrd.systemd.services."sysroot.mount" = {
unitConfig = {
Requires = [ "unlock-bcachefs-custom.service" ];
After = [ "unlock-bcachefs-custom.service" ];
};
};
boot.initrd.systemd.services.unlock-bcachefs-custom = {
description = "Custom single bcachefs unlock for all subvolumes";
# Make this part of the root-fs chain, not just initrd.target
wantedBy = [
# "initrd.target"
"sysroot.mount"
"initrd-root-fs.target"
];
# Stronger than wantedBy if you want it absolutely required:
requiredBy = [
"sysroot.mount"
"initrd-root-fs.target"
];
before = [
"sysroot.mount"
"initrd-root-fs.target"
];
requires = [
"usb_key.mount"
primaryDeviceUnit
];
after = [
"usb_key.mount"
primaryDeviceUnit
"initrd-root-device.target"
];
# script = ''
# echo "Using test password..."
#
# mkdir -p /usb_key
# # Wait for USB device (optional, to handle slow init)
# for i in $(seq 1 50); do
# if [ -b "${USB_KEY}" ]; then
# break
# fi
# echo "Waiting for USB key ${USB_KEY}..."
# sleep 0.2
# done
#
# if [ ! -b "${USB_KEY}" ]; then
# echo "USB key device ${USB_KEY} not present in initrd"
# exit 1
# fi
#
# # Mount the key
# mount -t bcachefs -o ro "${USB_KEY}" /usb_key
#
# echo "test" | ${pkgs.bcachefs-tools}/bin/bcachefs unlock "${PRIMARY}"
# echo "bcachefs unlock successful for ${PRIMARY}"
# '';
script = ''
echo "Using test password..."
echo "test" | ${pkgs.bcachefs-tools}/bin/bcachefs unlock "${PRIMARY}"
echo "bcachefs unlock successful for ${PRIMARY}"
'';
# script = ''
# echo "Using USB key for bcachefs unlock: ${USB_KEY}"
#
# echo "test" | ${pkgs.bcachefs-tools}/bin/bcachefs unlock "${PRIMARY}"
# echo "done...."
# exit 0
#
# # only try mount if the node exists
# if [ ! -e "${USB_KEY}" ]; then
# echo "USB key device ${USB_KEY} not present in initrd"
# exit 1
# fi
# ${pkgs.bcachefs-tools}/bin/bcachefs unlock -f /usb_key/key "${PRIMARY}"
# echo "bcachefs unlock successful for ${PRIMARY}"
# '';
};
# TODO rotate root
}
# Reset root for erase your darlings/impermanence/preservation
{
# boot.initrd.systemd.services.bcachefs-reset-root = {
# description = "Reset bcachefs root subvolume before pivot";
# wantedBy = [ "initrd.target" ];
#
# after = [
# "initrd-root-device.target"
# "cryptsetup.target"
# "unlock-bcachefs-custom"
# ];
# requires = [ primaryDeviceUnit ];
#
# serviceConfig = {
# Type = "oneshot";
# # initrd has a minimal PATH; set one explicitly
# Environment = "PATH=/bin:/sbin:/usr/bin:/usr/sbin";
# # If tools are in /usr, this helps ensure it's in the initrd
# # (you may also need environment.systemPackages + boot.initrd.includeDefaultModules)
# ExecStart = pkgs.writeShellScript "bcachefs-reset-root" ''
# set -euo pipefail
#
# PRIMARY=${PRIMARY}
#
# echo "Unlocking bcachefs volume ${PRIMARY}..."
# echo "test" | bcachefs unlock "''${PRIMARY}"
#
# mkdir -p /primary_tmp
# mount "''${PRIMARY}" /primary_tmp
#
# if [[ -e /primary_tmp/@root ]]; then
# mkdir -p /primary_tmp/@old_roots
# bcachefs set-file-option /primary_tmp/@old_roots --compression=zstd
#
# timestamp=$(date --date="@$(stat -c %Y /primary_tmp/@root)" "+%Y-%m-%-d_%H:%M:%S")
# bcachefs subvolume snapshot /primary_tmp/@root "/primary_tmp/@old_roots/$timestamp"
# bcachefs subvolume delete /primary_tmp/@root
#
# # Cleanup old snapshots (>30 days)
# # Note: path was /primary_tmp/old_roots in your snippet; using @old_roots for consistency
# for i in $(find /primary_tmp/@old_roots/ -maxdepth 1 -mtime +30); do
# bcachefs subvolume delete "$i"
# done
# fi
#
# bcachefs subvolume create /primary_tmp/@root
# umount /primary_tmp
# '';
# };
# };
}
]