Set default kernel interface name (#1014)

* Set default kernel interface name

Signed-off-by: Artem Glazychev <artem.glazychev@xored.com>

* fix review

Signed-off-by: Artem Glazychev <artem.glazychev@xored.com>

pkg/networkservice/common/mechanisms/kernel/client.go

@@ -47,14 +47,18 @@ func NewClient(options ...Option) networkservice.NetworkServiceClient {
 
 func (k *kernelMechanismClient) Request(ctx context.Context, request *networkservice.NetworkServiceRequest, opts ...grpc.CallOption) (*networkservice.Connection, error) {
 	if !k.updateMechanismPreferences(request) {
-		request.MechanismPreferences = append(request.GetMechanismPreferences(), &networkservice.Mechanism{
+		mechanism := &networkservice.Mechanism{
 			Cls:  cls.LOCAL,
 			Type: kernel.MECHANISM,
 			Parameters: map[string]string{
 				kernel.NetNSURL:         (&url.URL{Scheme: "file", Path: netNSFilename}).String(),
-				kernel.InterfaceNameKey: k.interfaceName,
+				kernel.InterfaceNameKey: GetNameFromConnection(request.GetConnection()),
 			},
-		})
+		}
+		if k.interfaceName != "" {
+			mechanism.Parameters[kernel.InterfaceNameKey] = k.interfaceName
+		}
+		request.MechanismPreferences = append(request.GetMechanismPreferences(), mechanism)
 	}
 	return next.Client(ctx).Request(ctx, request, opts...)
 }

pkg/networkservice/common/mechanisms/kernel/server.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2020 Doc.ai and/or its affiliates.
+// Copyright (c) 2020-2021 Doc.ai and/or its affiliates.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -39,6 +39,7 @@ func NewServer() networkservice.NetworkServiceServer {
 func (m *kernelMechanismServer) Request(ctx context.Context, request *networkservice.NetworkServiceRequest) (*networkservice.Connection, error) {
 	if mechanism := kernel.ToMechanism(request.GetConnection().GetMechanism()); mechanism != nil {
 		mechanism.SetNetNSURL((&url.URL{Scheme: "file", Path: netNSFilename}).String())
+		mechanism.SetInterfaceName(GetNameFromConnection(request.GetConnection()))
 	}
 	return next.Server(ctx).Request(ctx, request)
 }

pkg/networkservice/common/mechanisms/kernel/utils.go

@@ -0,0 +1,38 @@
+// Copyright (c) 2021 Doc.ai and/or its affiliates.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at:
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package kernel
+
+import (
+	"fmt"
+
+	"github.com/networkservicemesh/api/pkg/api/networkservice"
+	kernelmech "github.com/networkservicemesh/api/pkg/api/networkservice/mechanisms/kernel"
+)
+
+// GetNameFromConnection - returns a name computed from networkservice.Connection 'conn'
+func GetNameFromConnection(conn *networkservice.Connection) string {
+	ns := conn.GetNetworkService()
+	nsMaxLength := kernelmech.LinuxIfMaxLength - 5
+	if len(ns) > nsMaxLength {
+		ns = ns[:nsMaxLength]
+	}
+	name := fmt.Sprintf("%s-%s", ns, conn.GetId())
+	if len(name) > kernelmech.LinuxIfMaxLength {
+		name = name[:kernelmech.LinuxIfMaxLength]
+	}
+	return name
+}

pkg/networkservice/common/mechanismtranslation/client_test.go

@@ -1,4 +1,4 @@
-// Copyright (c) 2020 Doc.ai and/or its affiliates.
+// Copyright (c) 2020-2021 Doc.ai and/or its affiliates.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -37,7 +37,11 @@ import (
 )
 
 func kernelMechanism() *networkservice.Mechanism {
-	request := new(networkservice.NetworkServiceRequest)
+	request := &networkservice.NetworkServiceRequest{
+		Connection: &networkservice.Connection{
+			Id: "id",
+		},
+	}
 	_, _ = kernel.NewClient().Request(context.TODO(), request)
 	return request.MechanismPreferences[0]
 }