From 3248506a002a668f8697d4752f1db211501c2823 Mon Sep 17 00:00:00 2001
From: "Antoine R. Dumont (@ardumont)" <antoine.romain.dumont@gmail.com>
Date: Mon, 20 Jul 2020 08:47:16 +0200
Subject: [PATCH] mediatomb/gerbera: Improve firewall rules and open firewall
 option

This changes the default behavior which opened by default the firewall rules.
The users now need to declare explicitely they want to open the firewall.
---
 nixos/modules/services/misc/mediatomb.nix | 31 ++++++++++++++++++++---
 nixos/tests/mediatomb.nix                 |  7 ++---
 2 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/nixos/modules/services/misc/mediatomb.nix b/nixos/modules/services/misc/mediatomb.nix
index 9e5a0463faa1..ec6ef3d7b53a 100644
--- a/nixos/modules/services/misc/mediatomb.nix
+++ b/nixos/modules/services/misc/mediatomb.nix
@@ -182,6 +182,13 @@ let
     ${transcodingConfig}
   </config>
 '';
+  defaultFirewallRules = {
+    # udp 1900 port needs to be opened for SSDP (not configurable within
+    # mediatomb/gerbera) cf.
+    # http://docs.gerbera.io/en/latest/run.html?highlight=udp%20port#network-setup
+    allowedUDPPorts = [ 1900 cfg.port ];
+    allowedTCPPorts = [ cfg.port ];
+  };
 
 in {
 
@@ -294,6 +301,18 @@ in {
         '';
       };
 
+      openFirewall = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          If false (the default), this is up to the user to declare the firewall rules.
+          If true, this opens the 1900 (tcp and udp) and ${toString cfg.port} (tcp) ports.
+          If the option cfg.interface is set, the firewall rules opened are
+          dedicated to that interface. Otherwise, those rules are opened
+          globally.
+        '';
+      };
+
       uuid = mkOption {
         type = types.str;
         default = "fdfc8a4e-a3ad-4c1d-b43d-a2eedb03a687";
@@ -324,6 +343,7 @@ in {
           ${cfg.dataDir}/config.xml. It's up to the user to make a correct configuration file.
         '';
       };
+
     };
   };
 
@@ -356,9 +376,12 @@ in {
       };
     };
 
-    networking.firewall.interfaces."${cfg.interface}" = {
-      allowedUDPPorts = [ 1900 cfg.port ];
-      allowedTCPPorts = [ cfg.port ];
-    };
+    # Open firewall only if users enable it
+    networking.firewall = mkMerge [
+      (mkIf (cfg.openFirewall && cfg.interface != "") {
+        interfaces."${cfg.interface}" = defaultFirewallRules;
+      })
+      (mkIf (cfg.openFirewall && cfg.interface == "") defaultFirewallRules)
+    ];
   };
 }
diff --git a/nixos/tests/mediatomb.nix b/nixos/tests/mediatomb.nix
index f07e453aadc2..b7a126a01ad5 100644
--- a/nixos/tests/mediatomb.nix
+++ b/nixos/tests/mediatomb.nix
@@ -14,15 +14,12 @@ import ./make-test-python.nix ({ pkgs, ... }:
           serverName = "Gerbera";
           package = pkgs.gerbera;
           interface = "eth1";  # accessible from test
+          openFirewall = true;
           mediaDirectories = [
             { path = "/var/lib/gerbera/pictures"; recursive = false; hidden-files = false; }
             { path = "/var/lib/gerbera/audio"; recursive = true; hidden-files = false; }
           ];
         };
-        networking.firewall = {
-          allowedUDPPorts = [ 1900 port ];
-          allowedTCPPorts = [ port ];
-        };
       };
 
     serverMediatomb =
@@ -41,7 +38,7 @@ import ./make-test-python.nix ({ pkgs, ... }:
             { path = "/var/lib/mediatomb/audio"; recursive = true; hidden-files = false; }
           ];
         };
-        networking.firewall = {
+        networking.firewall.interfaces.eth1 = {
           allowedUDPPorts = [ 1900 port ];
           allowedTCPPorts = [ port ];
         };