From 864c1856b89b1a66c2d6566bfc36dbb69810e14f Mon Sep 17 00:00:00 2001
From: Ember 'n0emis' Keske <git@n0emis.eu>
Date: Sat, 12 Mar 2022 12:10:32 +0100
Subject: [PATCH] configure radvd

---
 default.nix         | 11 +++++++++--
 modules/default.nix | 33 ++++++++++++++++++++++++++++-----
 2 files changed, 37 insertions(+), 7 deletions(-)

diff --git a/default.nix b/default.nix
index 9dbc68e..42cf991 100644
--- a/default.nix
+++ b/default.nix
@@ -45,13 +45,19 @@ in
           ipv6Prefixes = mkOption {
             type = types.listOf types.str;
           };
-          addresses = mkOption {
+          ipv4Addresses = mkOption {
             type = types.listOf types.str;
             description = ''
-              Addresses to be configured on the bridge interface.
+              IPv4 Addresses to be configured on the bridge interface.
               WARNING: the primary-ipv4-address to be send as a gateway address via DHCP has to be the first one.
             '';
           };
+          ipv6Addresses = mkOption {
+            type = types.listOf types.str;
+            description = ''
+              IPv6 Addresses to be configured on the bridge interface.
+            '';
+          };
           routingTable = mkOption {
             type = types.int;
           };
@@ -60,6 +66,7 @@ in
             default = true;
             description = ''
               Create a Null-Route in the routing-table to allow traffic leaks on the gateways default route when uplink is down.
+              The first address will be sen't as the DNS-Server via RAs.
             '';
           };
           mtu = mkOption {
diff --git a/modules/default.nix b/modules/default.nix
index 567fa90..f2106e2 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -8,6 +8,7 @@ let
 
   mkDomain = name: domCfg:
     let
+      cidrToAddress = cidr: head (splitString "/" cidr);
       mkIfName = type:
         if type == "bridge" then "br-${name}" else
         if type == "batman" then "bat-${name}" else
@@ -47,7 +48,7 @@ let
           RequiredForOnline = "no";
           MTUBytes = "${toString domCfg.mtu}";
         };
-        address = domCfg.addresses;
+        address = domCfg.ipv4Addresses ++ domCfg.ipv6Addresses;
         routes = map (prefix: {
           routeConfig = {
             Destination = prefix;
@@ -129,11 +130,11 @@ let
         option-data = [
           {
             name = "routers";
-            data = head domCfg.addresses;
+            data = cidrToAddress (head domCfg.ipv4Addresses);
           }
           {
             name = "domain-name-servers";
-            data = head domCfg.addresses;
+            data = cidrToAddress (head domCfg.ipv4Addresses);
           }
           {
             name = "domain-name";
@@ -141,15 +142,32 @@ let
           }
         ];
       } // domCfg.dhcpExtraConfig) ]);
+
+      #### RADVD ####
+      radvdConfig = let
+        radvdPrefixes = if domCfg.radvdPrefixes == [] then domCfg.ipv6Prefixes else domCfg.radvdPrefixes;
+        mkPrefix = prefix: ''
+          prefix ${prefix} { };
+        '';
+      in if (!domCfg.enableRadvd) then [] else [ ''
+        interface ${mkIfName "bridge"} {
+          IgnoreIfMissing on;
+          AdvSendAdvert on;
+          AdvLinkMTU ${toString domCfg.mtu};
+          RDNSS ${cidrToAddress (head domCfg.ipv6Addresses)} { };
+          DNSSL ${domCfg.searchDomain} { };
+
+          ${concatStringsSep "\n" (map mkPrefix radvdPrefixes)}
+        };
+      '' ];
     };
 
     domConfigs = map (key: getAttr key (mapAttrs mkDomain activeDomains)) (attrNames activeDomains);
-    mergedConfigs = mapAttrs (name: value: mkMerge value) (attrsets.zipAttrs (map (x: removeAttrs x [ "foo" ]) domConfigs));
+    mergedConfigs = mapAttrs (name: value: mkMerge value) (attrsets.zipAttrs (map (x: removeAttrs x [ ]) domConfigs));
 
 in
 {
   config = mkIf cfg.enable {
-    environment.etc."ffnix.json".source = pkgs.writeText "ffnix.json" (generators.toJSON {} activeDomains);
     systemd.network.netdevs = mergedConfigs.netdevs;
     systemd.network.networks = mergedConfigs.networks;
     systemd.network.links = mergedConfigs.links;
@@ -167,5 +185,10 @@ in
         subnet4 = mergedConfigs.keaSubnet4;
       };
     };
+
+    services.radvd = mkIf (concatLists mergedConfigs.radvdConfig.contents != []) {
+      enable = true;
+      config = concatStringsSep "\n" (concatLists mergedConfigs.radvdConfig.contents);
+    };
   };
 }