nixos-config/lib/fudo/password.nix

117 lines
3.4 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.fudo.password;
genOpts = {
options = {
file = mkOption {
type = types.str;
description = "Password file in which to store a generated password.";
};
user = mkOption {
type = types.str;
description = "User to which the file should belong.";
};
group = mkOption {
type = with types; nullOr str;
description = "Group to which the file should belong.";
default = "nogroup";
};
restart-services = mkOption {
type = with types; listOf str;
description = "List of services to restart when the password file is generated.";
default = [];
};
};
};
generate-passwd-file = file: user: group: pkgs.writeShellScriptBin "generate-passwd-file.sh" ''
mkdir -p $(dirname ${file})
if touch ${file}; then
chown ${user}${optionalString (group != null) ":${group}"} ${file}
if [ $? -ne 0 ]; then
rm ${file}
echo "failed to set permissions on ${file}"
exit 4
fi
${pkgs.pwgen}/bin/pwgen 30 1 > ${file}
else
echo "cannot write to ${file}"
exit 2
fi
if [ ! -f ${file} ]; then
echo "Failed to create file ${file}"
exit 3
fi
${if (group != null) then
"chmod 640 ${file}"
else
"chmod 600 ${file}"}
echo "created password file ${file}"
exit 0
'';
restart-script = service-name: ''
SYSCTL=${pkgs.systemd}/bin/systemctl
JOBTYPE=$(${pkgs.systemd}/bin/systemctl show ${service-name} -p Type)
if $SYSCTL is-active --quiet ${service-name} ||
[ $JOBTYPE == "Type=simple" ] ||
[ $JOBTYPE == "Type=oneshot" ] ; then
echo "restarting service ${service-name} because password has changed."
$SYSCTL restart ${service-name}
fi
'';
filterForRestarts = filterAttrs (name: opts: opts.restart-services != []);
in {
options.fudo.password = {
file-generator = mkOption {
type = with types; loaOf (submodule genOpts);
description = "List of password files to generate.";
default = {};
};
};
config = {
systemd.targets.fudo-passwords = {
description = "Target indicating that all Fudo passwords have been generated.";
wantedBy = [ "default.target" ];
};
systemd.services = fold (a: b: a // b) {} (mapAttrsToList (name: opts: {
"file-generator-${name}" = {
enable = true;
partOf = [ "fudo-passwords.target" ];
serviceConfig.Type = "oneshot";
description = "Generate password file for ${name}.";
script = "${generate-passwd-file opts.file opts.user opts.group}/bin/generate-passwd-file.sh";
reloadIfChanged = true;
};
"file-generator-watcher-${name}" = mkIf (! (opts.restart-services == [])) {
description = "Restart services upon regenerating password for ${name}";
after = [ "file-generator-${name}.service" ];
partOf = [ "fudo-passwords.target" ];
serviceConfig.Type = "oneshot";
script = concatStringsSep "\n" (map restart-script opts.restart-services);
};
}) cfg.file-generator);
systemd.paths = mapAttrs' (name: opts:
nameValuePair "file-generator-watcher-${name}" {
partOf = [ "fudo-passwords.target"];
pathConfig.PathChanged = opts.file;
}) (filterForRestarts cfg.file-generator);
};
}