nixos/hosts/common/optional/nixos-containers/xmpp.nix

{
  pkgs,
  lib,
  configVars,
  inputs,
  ...
}: let
  containerName = "xmpp";
  xmppDomain = configVars.domains.xmpp;
  pubKeys = lib.filesystem.listFilesRecursive ../../users/keys;
  hostAddress = configVars.networking.addresses.xmpp.hostAddress;
  localAddress = configVars.networking.addresses.xmpp.localAddress;
  sops-nix = inputs.sops-nix;
  xmppPorts = [3478 5281 5280 5269 5222 5223];
in {
  networking = {
    nat = {
      enable = true;
      internalInterfaces = ["ve-+"];
      externalInterface = "enp1s0";
    };
    firewall = {
      enable = true;
      allowedTCPPorts = xmppPorts;
    };
  };

  environment.persistence."/persist" = {
    hideMounts = true;
    directories = [
      "/var/lib/nixos-containers/${containerName}"
    ];
  };

  systemd.tmpfiles.rules = [
    "d /var/lib/prosody 0750"
  ];

  containers."${containerName}" = {
    autoStart = true;
    privateNetwork = true;
    hostAddress = hostAddress;
    localAddress = localAddress;
    nixpkgs = pkgs.path;
    bindMounts = {
      "/etc/ssh/ssh_host_ed25519_key" = {
        hostPath = "/etc/ssh/ssh_host_ed25519_key";
        isReadOnly = true;
      };
      "/var/lib/prosody" = {
        hostPath = "/var/lib/prosody";
        isReadOnly = false;
      };
      "/var/lib/acme/${xmppDomain}/" = {
        hostPath = "/var/lib/acme/${xmppDomain}/";
        isReadOnly = false;
      };
    };
    forwardPorts =
      lib.map (port: {
        containerPort = port;
        hostPort = port;
      })
      xmppPorts;
    config = {
      pkgs,
      lib,
      config,
      ...
    }: let
      secretsDirectory = builtins.toString inputs.nix-secrets;
      secretsFile = "${secretsDirectory}/secrets.yaml";
    in {
      users.groups.www-data = {
        gid = 33;
      };

      users.users.prosody = {
        isSystemUser = true;
        uid = 149;
        extraGroups = ["www-data"];
      };

      networking = {
        firewall = {
          enable = true;
          rejectPackets = true;
          allowedTCPPorts = xmppPorts ++ [80 443];
        };
        useHostResolvConf = lib.mkForce false;
      };

      services.resolved.enable = true;

      sops = {
        defaultSopsFile = "${secretsFile}";
        validateSopsFiles = false;

        age = {
          sshKeyPaths = ["/etc/ssh/ssh_host_ed25519_key"];
        };
        secrets = {
          "software/coturn/static-auth-secret" = {
            mode = "0644";
          };
        };
      };

      imports = [
        sops-nix.nixosModules.sops
      ];

      environment.systemPackages = [
        pkgs.vim
        pkgs.git
        pkgs.prosody
      ];

      sops.templates."prosody_secrets.lua" = {
        mode = "644";
        content = ''
          turn_external_secret = ${config.sops.placeholder."software/coturn/static-auth-secret"};
        '';
      };

      services.prosody = {
        enable = true;
        package = pkgs.prosody.override {
          withCommunityModules = [
            "turn_external"
            "conversejs"
            "admin_web"
          ];
        };
        extraModules = ["turn_external" "conversejs" "admin_web" "http" "websocket"];
        allowRegistration = true;
        extraConfig = ''
          include "${config.sops.templates."prosody_secrets.lua".path}"
          registration_invite_only = true;
          allow_user_invites = true;
          cross_domain_bosh = true;
          turn_external_host = "turn.${xmppDomain}";
          turn_external_port = 3478;
          http_default_host = "${xmppDomain}";
          certificates = "certs"
          cross_domain_websocket = { "https://${xmppDomain}" }
          consider_websocket_secure = true
          
          legacy_ssl_ports = { 5223 }
          legacy_ssl_ssl = {
            certificate = "/var/lib/acme/${xmppDomain}/cert.pem";
            key = "/var/lib/acme/${xmppDomain}/key.pem";
          }

        '';
        modules.bosh = true;
        s2sRequireEncryption = true;
        c2sRequireEncryption = true;
        s2sSecureAuth = false;
        admins = ["root@${xmppDomain}"];
        ssl.cert = "/var/lib/acme/${xmppDomain}/fullchain.pem";
        ssl.key = "/var/lib/acme/${xmppDomain}/key.pem";
        virtualHosts."${xmppDomain}" = {
          enabled = true;
          ssl.cert = "/var/lib/acme/${xmppDomain}/fullchain.pem";
          ssl.key = "/var/lib/acme/${xmppDomain}/key.pem";
          extraConfig = ''
            http_external_url = "https://chat.${xmppDomain}/"
            invites_page = "https://chat.${xmppDomain}/register?t={invite.token}"
            http_paths = {
              invites_page = "/invite";
              invites_register_web = "/register";
            }
          '';
          domain = "${xmppDomain}";
        };
        muc = [
          {
            domain = "conference.${xmppDomain}";
          }
        ];
        uploadHttp = {
          domain = "https://upload.${xmppDomain}";
          uploadFileSizeLimit = "1000000000"; # 1 gb file-size limit
          uploadExpireAfter = "31557600"; # files deleted after 1 year
        };
      };

      services.coturn = {
        enable = true;
        realm = "turn.${xmppDomain}";
        use-auth-secret = true;
        static-auth-secret-file = config.sops.secrets."software/coturn/static-auth-secret".path;
      };

      services.openssh = {
        enable = true;
        settings.PasswordAuthentication = false;
      };

      users.users = {
        root = {
          openssh.authorizedKeys.keys = lib.lists.forEach pubKeys (key: builtins.readFile key);
        };
      };

      system.stateVersion = "24.05";
    };
  };
}