Merge pull request #34442 from rnhmjoj/virtual

Fix virtualType for network-interfaces-scripted

nixos/modules/tasks/network-interfaces-scripted.nix

@@ -230,9 +230,7 @@ let
               RemainAfterExit = true;
             };
             script = ''
-              ip tuntap add dev "${i.name}" \
+              ip tuntap add dev "${i.name}" mode "${i.virtualType}" user "${i.virtualOwner}"
-              ${optionalString (i.virtualType != null) "mode ${i.virtualType}"} \
-              user "${i.virtualOwner}"
             '';
             postStop = ''
               ip link del ${i.name} || true

nixos/modules/tasks/network-interfaces-systemd.nix

@@ -74,21 +74,17 @@ in
         networks."99-main" = genericNetwork mkDefault;
       }
       (mkMerge (flip map interfaces (i: {
-        netdevs = mkIf i.virtual (
+        netdevs = mkIf i.virtual ({
-          let
+          "40-${i.name}" = {
-            devType = if i.virtualType != null then i.virtualType
+            netdevConfig = {
-              else (if hasPrefix "tun" i.name then "tun" else "tap");
+              Name = i.name;
-          in {
+              Kind = i.virtualType;
-            "40-${i.name}" = {
-              netdevConfig = {
-                Name = i.name;
-                Kind = devType;
-              };
-              "${devType}Config" = optionalAttrs (i.virtualOwner != null) {
-                User = i.virtualOwner;
-              };
             };
-          });
+            "${i.virtualType}Config" = optionalAttrs (i.virtualOwner != null) {
+              User = i.virtualOwner;
+            };
+          };
+        });
         networks."40-${i.name}" = mkMerge [ (genericNetwork mkDefault) {
           name = mkDefault i.name;
           DHCP = mkForce (dhcpStr

nixos/modules/tasks/network-interfaces.nix

@@ -273,11 +273,13 @@ let
       };
 
       virtualType = mkOption {
-        default = null;
+        default = if hasPrefix "tun" name then "tun" else "tap";
-        type = with types; nullOr (enum [ "tun" "tap" ]);
+        defaultText = literalExample ''if hasPrefix "tun" name then "tun" else "tap"'';
+        type = with types; enum [ "tun" "tap" ];
         description = ''
-          The explicit type of interface to create. Accepts tun or tap strings.
+          The type of interface to create.
-          Also accepts null to implicitly detect the type of device.
+          The default is TUN for an interface name starting
+          with "tun", otherwise TAP.
         '';
       };
 

nixos/tests/networking.nix

@@ -433,6 +433,49 @@ let
           $client2->succeed("ip addr show dev vlan >&2");
         '';
     };
+    virtual = {
+      name = "Virtual";
+      machine = {
+        networking.interfaces."tap0" = {
+          ip4 = [ { address = "192.168.1.1"; prefixLength = 24; } ];
+          ip6 = [ { address = "2001:1470:fffd:2096::"; prefixLength = 64; } ];
+          virtual = true;
+        };
+        networking.interfaces."tun0" = {
+          ip4 = [ { address = "192.168.1.2"; prefixLength = 24; } ];
+          ip6 = [ { address = "2001:1470:fffd:2097::"; prefixLength = 64; } ];
+          virtual = true;
+        };
+      };
+
+      testScript = ''
+        my $targetList = <<'END';
+        tap0: tap UNKNOWN_FLAGS:800 user 0
+        tun0: tun UNKNOWN_FLAGS:800 user 0
+        END
+
+        # Wait for networking to come up
+        $machine->start;
+        $machine->waitForUnit("network.target");
+
+        # Test interfaces set up
+        my $list = $machine->succeed("ip tuntap list | sort");
+        "$list" eq "$targetList" or die(
+          "The list of virtual interfaces does not match the expected one:\n",
+          "Result:\n", "$list\n",
+          "Expected:\n", "$targetList\n"
+        );
+
+        # Test interfaces clean up
+        $machine->succeed("systemctl stop network-addresses-tap0");
+        $machine->succeed("systemctl stop network-addresses-tun0");
+        my $residue = $machine->succeed("ip tuntap list");
+        $residue eq "" or die(
+          "Some virtual interface has not been properly cleaned:\n",
+          "$residue\n"
+        );
+      '';
+    };
   };
 
 in mapAttrs (const (attrs: makeTest (attrs // {