config.security.googleOsLogin: add module

The OS Login package enables the following components:
AuthorizedKeysCommand to query valid SSH keys from the user's OS Login
profile during ssh authentication phase.
NSS Module to provide user and group information
PAM Module for the sshd service, providing authorization and
authentication support, allowing the system to use data stored in
Google Cloud IAM permissions to control both, the ability to log into
an instance, and to perform operations as root (sudo).
This commit is contained in:
Florian Klink 2018-12-12 13:55:25 +01:00
parent be5ad774bf
commit c6de45c0d7
2 changed files with 69 additions and 0 deletions

View file

@ -154,6 +154,7 @@
./security/chromium-suid-sandbox.nix
./security/dhparams.nix
./security/duosec.nix
./security/google_oslogin.nix
./security/hidepid.nix
./security/lock-kernel-modules.nix
./security/misc.nix

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@ -0,0 +1,68 @@
{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.security.googleOsLogin;
package = pkgs.google-compute-engine-oslogin;
in
{
options = {
security.googleOsLogin.enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to enable Google OS Login
The OS Login package enables the following components:
AuthorizedKeysCommand to query valid SSH keys from the user's OS Login
profile during ssh authentication phase.
NSS Module to provide user and group information
PAM Module for the sshd service, providing authorization and
authentication support, allowing the system to use data stored in
Google Cloud IAM permissions to control both, the ability to log into
an instance, and to perform operations as root (sudo).
'';
};
};
config = mkIf cfg.enable {
security.pam.services.sshd = {
makeHomeDir = true;
googleOsLoginAccountVerification = true;
# disabled for now: googleOsLoginAuthentication = true;
};
security.sudo.extraConfig = ''
#includedir /run/google-sudoers.d
'';
systemd.tmpfiles.rules = [
"d /run/google-sudoers.d 750 root root -"
"d /var/google-users.d 750 root root -"
];
# enable the nss module, so user lookups etc. work
system.nssModules = [ package ];
# Ugly: sshd refuses to start if a store path is given because /nix/store is group-writable.
# So indirect by a symlink.
environment.etc."ssh/authorized_keys_command_google_oslogin" = {
mode = "0755";
text = ''
#!/bin/sh
exec ${package}/bin/google_authorized_keys "$@"
'';
};
services.openssh.extraConfig = ''
AuthorizedKeysCommand /etc/ssh/authorized_keys_command_google_oslogin %u
AuthorizedKeysCommandUser nobody
'';
};
}