nixos: add dump option to child uplinks

nixos-modules/hardware/nic.nix

@@ -3,59 +3,10 @@
 with lib;
 
 {
-  options = {
-
-    networking.interfaces = lib.mkOption {
-      type = with types;
-        attrsOf (submodule ({ ... }: {
-          options.genode = {
-
-            driver = mkOption { type = types.enum [ "ipxe" "virtio" ]; };
-
-            stack = mkOption {
-              type = with types; nullOr (enum [ "lwip" "lxip" ]);
-              default = "lwip";
-            };
-
-          };
-        }));
-    };
-
-  };
 
   config =
     # TODO: create drivers in both the first and second level inits
     {
-
-      assertions = with builtins;
-        let
-          addrCheck = name: interface: {
-            assertion = lessThan (length interface.ipv4.addresses) 2;
-            message = "Genode interfaces do not support multihoming.";
-          };
-          routeCheck = name: interface: {
-            assertion = lessThan (length interface.ipv4.routes) 2;
-            message = "Genode interfaces do not support multiple routes.";
-          };
-          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.core.children);
-            in {
-              assertion = clientList == [ ] || length clientList == 1;
-              message = "Multiple routes to Nic ${name}, ${clientList}";
-            };
-        in lib.lists.concatMap
-        (f: lib.mapAttrsToList f config.networking.interfaces) [
-          addrCheck
-          routeCheck
-          policyCheck
-        ];
-
       hardware.genode.platform.policies = let
         mkPolicy = { name, platformPolicy }:
           pkgs.writeText "${name}.policy.dhall" ''${platformPolicy} "${name}"'';
@@ -64,7 +15,7 @@ with lib;
           (child: childAttrs:
             lib.attrsets.mapAttrsToList (uplink: uplinkAttrs:
               mkPolicy {
-                name = "${child}-${uplink}.driver";
+                name = "${child}-${uplink}-driver";
                 inherit (uplinkAttrs) platformPolicy;
               }) childAttrs.uplinks) config.genode.core.children);
 
@@ -72,13 +23,13 @@ with lib;
 
       genode.core.supportChildren = let
 
-        mkUplinkDriver = { policyPrefix, driver, verbose }: {
+        mkUplinkDriver = { name, policyPrefix, driver, verbose }: {
           package = with pkgs.genodePackages;
             {
               ipxe = ipxe_nic_drv;
               virtio = virtio_nic_drv;
             }.${driver};
-          configFile = pkgs.writeText "driver.dhall" ''
+          configFile = pkgs.writeText "${name}.dhall" ''
             let Genode = env:DHALL_GENODE
 
             let Init = Genode.Init
@@ -104,15 +55,53 @@ with lib;
           '';
         };
 
-        otherDrivers = builtins.concatLists (lib.attrsets.mapAttrsToList
-          (child: childAttrs:
-            lib.attrsets.mapAttrsToList (uplink: uplinkAttrs: {
-              name = "${child}-${uplink}.driver";
-              value = mkUplinkDriver {
-                policyPrefix = "${child} -> ${uplink}";
-                inherit (uplinkAttrs) driver verbose;
-              };
-            }) childAttrs.uplinks) config.genode.core.children);
+        mkUplinkDump = { name, childName, policyPrefix }: {
+          package = pkgs.genodePackages.nic_dump;
+          configFile = pkgs.writeText "${name}.dhall" ''
+            let Genode = env:DHALL_GENODE
+
+            let Init = Genode.Init
+
+            in  λ(binary : Text) →
+                  Init.Child.flat
+                    Init.Child.Attributes::{
+                    , binary
+                    , resources = Init.Resources::{ caps = 128, ram = Genode.units.MiB 6 }
+                    , config = Init.Config::{
+                      , attributes = toMap { downlink = "${childName}", uplink = "driver" }
+                      , policies =
+                        [ Init.Config.Policy::{
+                          , service = "Nic"
+                          , label = Init.LabelSelector.prefix "${policyPrefix}"
+                          }
+                        ]
+                      }
+                    }
+          '';
+        };
+
+        otherDrivers = lib.lists.flatten (lib.attrsets.mapAttrsToList
+          (childName:
+            { uplinks, ... }:
+            lib.attrsets.mapAttrsToList (uplink:
+              let
+                childLabel = "${childName} -> ${uplink}";
+                driverName = "${childName}-${uplink}-driver";
+                dumpName = "${childName}-${uplink}-dump";
+              in { driver, dump, verbose, ... }:
+              [(rec {
+                name = driverName;
+                value = mkUplinkDriver {
+                  inherit name driver verbose;
+                  policyPrefix = if dump then dumpName else childLabel;
+                };
+              })] ++ lib.lists.optional dump (rec {
+                name = dumpName;
+                value = mkUplinkDump {
+                  inherit name childName;
+                  policyPrefix = childLabel;
+                };
+              })) uplinks) config.genode.core.children);
 
       in builtins.listToAttrs otherDrivers;
     };

nixos-modules/lib/uplinks-option.nix

@@ -7,6 +7,7 @@ mkOption {
     attrsOf (submodule {
       options = {
         driver = mkOption { type = types.enum [ "ipxe" "virtio" ]; };
+        dump = mkEnableOption "packet logging";
         platformPolicy = mkOption {
           type = types.path;
           default = builtins.toFile "driver.policy.dhall" ''