nixos-config/machine/vps/configuration.nix

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

{
  imports =
    [ # Include the results of the hardware scan.
      /etc/nixos/hardware-configuration.nix
      ../../configs/common.nix
      ../../configs/virtualisation.nix
      (fetchTarball "https://github.com/msteen/nixos-vscode-server/tarball/master")
    ];

  # Use the GRUB 2 boot loader.
  boot.loader.grub.enable = true;
  boot.loader.grub.version = 2;
  boot.loader.grub.device = "/dev/sda"; # or "nodev" for efi only

  networking.hostName = "vps"; # Define your hostname.

  # Set your time zone.
  time.timeZone = "Europe/Berlin";
  networking.useDHCP = false;
  networking.interfaces.ens3.useDHCP = true;
  services.vscode-server.enable = true;

  # Define a user account. Don't forget to set a password with ‘passwd’.
  users = {
    defaultUserShell = pkgs.zsh;

    users.alex = {
     isNormalUser = true;
     extraGroups = [ "wheel" "docker" ];
    };
  };

  programs.zsh = {
    enable = true;

    enableCompletion = true;
    autosuggestions.enable = true;
    syntaxHighlighting.enable = true;

    ohMyZsh = {
      enable = true;
      theme = "agnoster";
      plugins = [
        "cp"
        "common-aliases"
        "docker "
        "systemd"
        "wd"
        "kubectl"
        "git"
      ];
    };
  };


  # List packages installed in system profile. To search, run:
  environment.systemPackages = with pkgs; [
    docker-compose
    glances
    htop
    git
    nodejs
  ];

  # Some programs need SUID wrappers, can be configured further or are
  # started in user sessions.
  # programs.mtr.enable = true;
  # programs.gnupg.agent = {
  #   enable = true;
  #   enableSSHSupport = true;
  # };

  # List services that you want to enable:

  # Enable the OpenSSH daemon.
  services.openssh = {
    enable = true;
    permitRootLogin = "no";
    passwordAuthentication = false;
    openFirewall = true;
  };

  security.acme.email = "webmaster@szczepan.ski";
  security.acme.acceptTerms = true;
  services.nginx = {
    enable = true;

    recommendedGzipSettings = true;
    recommendedOptimisation = true;
    recommendedProxySettings = true;
    recommendedTlsSettings = true;

    virtualHosts = {
      "szczepan.ski" = {
        forceSSL = true;
        enableACME = true;
        #root = "/var/www/myhost.org";
      };
      "nextcloud.szczepan.ski" = {
        forceSSL = true;
        enableACME = true;
        locations = {
          "/" = {
            proxyPass = "http://localhost:8080/";
            extraConfig = ''
              add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload";
            '';
          };
          "/.well-known/carddav" = {
             return = "301 $scheme://$host/remote.php/dav";
          };
          "/.well-known/caldav" = {
             return = "301 $scheme://$host/remote.php/dav";
          };
        };
      };
    };
  };

  services.fail2ban = {
    enable = true;

    jails.DEFAULT =
    ''
      bantime  = 7d
    '';

    jails.sshd =
    ''
      filter = sshd
      maxretry = 4
      action   = iptables[name=ssh, port=ssh, protocol=tcp]
      enabled  = true
    '';

    jails.sshd-ddos =
    ''
      filter = sshd-ddos
      maxretry = 2
      action   = iptables[name=ssh, port=ssh, protocol=tcp]
      enabled  = true
    '';
  };

  environment.etc."fail2ban/filter.d/sshd-ddos.conf" = {
    enable = true;
    text = ''
      [Definition]
      failregex = sshd(?:\[\d+\])?: Did not receive identification string from <HOST>$
      ignoreregex =
    '';
  };

  # Limit stack size to reduce memory usage
  systemd.services.fail2ban.serviceConfig.LimitSTACK = 256 * 1024;

  # Open ports in the firewall.
  networking.firewall.allowedTCPPorts = [ 80 443 ];
  networking.firewall.allowedUDPPorts = [ 80 443 ];
  # Or disable the firewall altogether.
  # networking.firewall.enable = false;

  # This value determines the NixOS release from which the default
  # settings for stateful data, like file locations and database versions
  # on your system were taken. It‘s perfectly fine and recommended to leave
  # this value at the release version of the first install of this system.
  # Before changing this value read the documentation for this option
  # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
  system.stateVersion = "21.05"; # Did you read the comment?

}