nixos: genode.init.children.<…>.routeToNics

Allow init children to route to Nic servers.

nixos-modules/genode-init.nix

@@ -58,6 +58,16 @@ in {
         attrsOf (submodule {
           options = {
             inherit coreROMs inputs;
+
+            routeToNics = lib.mkOption {
+              type = with types; listOf str;
+              default = [ ];
+              example = [ "eth0" ];
+              description = ''
+                Grant access to these Nic interfaces.
+              '';
+            };
+
             configFile = mkOption {
               type = types.path;
               description = ''

nixos-modules/hardware.nix

@@ -72,8 +72,25 @@ with lib;
           assertion = lessThan (length interface.ipv4.routes) 2;
           message = "Genode interfaces do not support multiple routes.";
         };
-      in lib.mapAttrsToList addrCheck config.networking.interfaces
-      ++ lib.mapAttrsToList routeCheck config.networking.interfaces;
+        policyCheck = name: interface:
+          let
+            clientList = filter (x x != null) (lib.mapAttrsToList
+              (childName: value:
+                if any (nic: nic == name) value.routeToNics then
+                  childName
+                else
+                  null) config.genode.init.children);
+          in {
+            assertion =
+              trace clientList (clientList == [ ] || length clientList == 1);
+            message = "Multiple routes to Nic ${name}, ${clientList}";
+          };
+      in lib.lists.concatMap
+      (f: lib.mapAttrsToList f config.networking.interfaces) [
+        addrCheck
+        routeCheck
+        policyCheck
+      ];
 
     hardware.genode.usb.storage.enable = config.genode.boot.storeBackend
       == "usb";
@@ -139,15 +156,15 @@ with lib;
           in {
             inputs = [ binary ];
             configFile = let
-              policies = if interface.genode.stack == null then
-                "[] : List Init.Config.Policy.Type"
-              else ''
-                [ Init.Config.Policy::{
+              policy = lib.mapAttrsToList (childName: value:
+                if any (nic: nic == name) value.routeToNics then ''
+                  Init.Config.Policy::{
                   , service = "Nic"
-                  , label = Init.LabelSelector.prefix "${name}.sockets"
+                  , label = Init.LabelSelector.prefix "${childName}"
                   }
-                ]
-              '';
+                '' else
+                  "") config.genode.init.children;
+
             in pkgs.writeText "${name'}.dhall" ''
               let Genode = env:DHALL_GENODE
 
@@ -166,7 +183,9 @@ with lib;
                       ]
                     , config = Init.Config::{
                       , attributes = toMap { verbose = "true" }
-                      , policies = ${policies}
+                      , policies =
+                            [ ${toString policy} ]
+                          : List Init.Config.Policy.Type
                       }
                     }
             '';
@@ -180,11 +199,15 @@ with lib;
           value = if interface.genode.stack == null then
             null
           else {
+
             inputs = with pkgs.genodePackages;
               {
                 lwip = [ vfs_lwip ];
                 lxip = [ vfs_lxip ];
               }.${interface.genode.stack};
+
+            routeToNics = [ name ];
+
             configFile = let
               binary = "${pkgs.genodePackages.vfs}/bin/vfs";
               ram = {
@@ -251,6 +274,7 @@ with lib;
                       }
                     }
             '';
+
           };
         }) config.networking.interfaces;
 
@@ -308,7 +332,9 @@ with lib;
                 , Init.ServiceRoute.parent "IO_PORT"
                 ]
               , config = Init.Config::{
-                , policies = [ ${toString policies} ]
+                , policies = [ ${
+                  toString policies
+                } ] : List Init.Config.Policy.Type
                 }
               }
       '';
@@ -361,7 +387,7 @@ with lib;
                               ]
                             }
                         ]
-                      , policies = [ storagePolicy ]
+                      , policies = [ storagePolicy ] : List Init.Config.Policy.Type
                       }
               }
       '';

tests/networking.nix

@@ -9,6 +9,9 @@
       networking.interfaces.eth1.genode.stack = null;
       genode.init.children.ping = {
         inputs = with pkgs.genodePackages; [ ping ];
+
+        routeToNics = [ "eth1" ];
+
         configFile = let
           ipA = builtins.head config.networking.interfaces.eth1.ipv4.addresses;
           ipAddrB = with builtins;