nixos-config/configuration.nix

# Edit this configuration file to define what should be installed on
#your system. Help is available in the configuration.nix(5) man page, on
# https://search.nixos.org/options and in the NixOS manual (`nixos-help`).

{ config, lib, pkgs, ... }:

{
  nix.settings.experimental-features = [ "nix-command" "flakes" ];
  
  sops.age.keyFile = "/secrets/age/keys.txt";

  imports =
    [ # Include the results of the hardware scan.
      ./hardware-configuration.nix
      ./users/users.nix
      ./services/gitea.nix
      ./services/duckddns.nix
    ];
  
  # Use the systemd-boot EFI boot loader.
  boot.loader.systemd-boot.enable = true;
  boot.loader.efi.canTouchEfiVariables = true;

  # set hostname
  networking.hostName = "rackserver";

  # fix nixpkgs warning
  nix.nixPath = [
    "nixpkgs=${pkgs.path}"
  ];

  # wireguard server setup
  # enable NAT
  networking.nat.enable = true;
  networking.nat.externalInterface = "eno4";
  networking.nat.internalInterfaces = [ "wg0" ];
  networking.firewall = {
    allowedUDPPorts = [ 51820 ];
  };

  networking.wireguard.interfaces = {
    # "wg0" is the network interface name. You can name the interface arbitrarily.
    wg0 = {
      # Determines the IP address and subnet of the server's end of the tunnel interface.
      ips = [ "10.100.0.1/24" ];

      # The port that WireGuard listens to. Must be accessible by the client.
      listenPort = 51820;

      # This allows the wireguard server to route your traffic to the internet and hence be like a VPN
      # For this to work you have to set the dnsserver IP of your router (or dnsserver of choice) in your clients
      postSetup = ''
        ${pkgs.iptables}/bin/iptables -t nat -A POSTROUTING -s 10.100.0.0/24 -o eno4 -j MASQUERADE
      '';

      # This undoes the above command
      postShutdown = ''
        ${pkgs.iptables}/bin/iptables -t nat -D POSTROUTING -s 10.100.0.0/24 -o eno4 -j MASQUERADE
      '';

      # Path to the private key file.
      #
      # Note: The private key can also be included inline via the privateKey option,
      # but this makes the private key world-readable; thus, using privateKeyFile is
      # recommended.
      privateKeyFile = "/run/keys/wg-privatekey"; # TODO: Change this to be a sops secret

      peers = [
        # List of allowed peers.
        { #nub
          # Public key of the peer (not a file path).
          publicKey = "L4msD0mEG2ctKDtaMJW2y3cs1fT2LBRVV7iVlWZ2nZc=";
          # List of IPs assigned to this peer within the tunnel subnet. Used to configure routing.
          allowedIPs = [ "10.100.0.2/32" ]; 
        } 
        { # ku
          publicKey = "L4msD0mEG2ctKDtaMJW2y3cs1fT2LBRVV7iVlWZ2nZc=";
          allowedIPs = [ "10.100.0.3/32" ]; 
        } 
        { # skyLaptop
          publicKey = "2sg0sgMMGQrCGt0f/5+1kO/B0Ghfb137DTf9nYctZTM=";
          allowedIPs = [ "10.100.0.4/32" ]; 
        } 
        { # skyDesktop
          publicKey = "L4msD0mEG2ctKDtaMJW2y3cs1fT2LBRVV7iVlWZ2nZc=";
          allowedIPs = [ "10.100.0.5/32" ];
        } 
      ];
    };
  };
  
  # arion setup
  virtualisation.podman.enable = true;
  virtualisation.podman.dockerSocket.enable = true;
  virtualisation.podman.defaultNetwork.settings.dns_enabled = true;

  environment.systemPackages = [
    pkgs.bash
    pkgs.wget
    pkgs.curl
    pkgs.vim
 
    pkgs.arion
    # Do install the docker CLI to talk to podman.
    # Not needed when virtualisation.docker.enable = true;
    pkgs.docker-client
  ];

  # List services that you want to enable:

  networking.firewall.allowedTCPPorts = [ 80 443 22 ];

  services.nginx = {
    enable = true;
    recommendedGzipSettings = true;
    recommendedOptimisation = true;
    recommendedProxySettings = true;
  };
  
  services.postgresql = {
    enable = true;
  };

  # Enable the OpenSSH daemon.
  services.openssh = {  
    enable = true;
    settings = {
      # Forbid root login through SSH.
      PermitRootLogin = "no";
      # key authentication
      PasswordAuthentication = false;
      KbdInteractiveAuthentication = false;
    };
  };

  # Open ports in the firewall.
  # networking.firewall.allowedTCPPorts = [ ... ];
  # networking.firewall.allowedUDPPorts = [ ... ];
  # Or disable the firewall altogether.
  # networking.firewall.enable = false;

  # Copy the NixOS configuration file and link it from the resulting system
  # (/run/current-system/configuration.nix). This is useful in case you
  # accidentally delete configuration.nix.
  # system.copySystemConfiguration = true;

  # This option defines the first version of NixOS you have installed on this particular machine,
  # and is used to maintain compatibility with application data (e.g. databases) created on older NixOS versions.
  #
  # Most users should NEVER change this value after the initial install, for any reason,
  # even if you've upgraded your system to a new NixOS release.
  #
  # This value does NOT affect the Nixpkgs version your packages and OS are pulled from,
  # so changing it will NOT upgrade your system.
  #
  # This value being lower than the current NixOS release does NOT mean your system is
  # out of date, out of support, or vulnerable.
  #
  # Do NOT change this value unless you have manually inspected all the changes it would make to your configuration,
  # and migrated your data accordingly.
  #
  # For more information, see `man configuration.nix` or https://nixos.org/manual/nixos/stable/options#opt-system.stateVersion .
  system.stateVersion = "23.11"; # Did you read the comment?
}