Merge branch 'master' into ip-forwarding

- Merges aleksej-paschenko's with HEAD
- Adds vfs2 support for ip_forward

1 files changed, 109 insertions, 0 deletions

diff --git a/pkg/tcpip/link/nested/nested_test.go b/pkg/tcpip/link/nested/nested_test.go
new file mode 100644
index 000000000..c1f9d308c
--- /dev/null
+++ b/pkg/tcpip/link/nested/nested_test.go
@@ -0,0 +1,109 @@
+// Copyright 2020 The gVisor Authors.
+//
+// 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 nested_test
+
+import (
+	"testing"
+
+	"gvisor.dev/gvisor/pkg/tcpip"
+	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/link/nested"
+	"gvisor.dev/gvisor/pkg/tcpip/stack"
+)
+
+type parentEndpoint struct {
+	nested.Endpoint
+}
+
+var _ stack.LinkEndpoint = (*parentEndpoint)(nil)
+var _ stack.NetworkDispatcher = (*parentEndpoint)(nil)
+
+type childEndpoint struct {
+	stack.LinkEndpoint
+	dispatcher stack.NetworkDispatcher
+}
+
+var _ stack.LinkEndpoint = (*childEndpoint)(nil)
+
+func (c *childEndpoint) Attach(dispatcher stack.NetworkDispatcher) {
+	c.dispatcher = dispatcher
+}
+
+func (c *childEndpoint) IsAttached() bool {
+	return c.dispatcher != nil
+}
+
+type counterDispatcher struct {
+	count int
+}
+
+var _ stack.NetworkDispatcher = (*counterDispatcher)(nil)
+
+func (d *counterDispatcher) DeliverNetworkPacket(tcpip.LinkAddress, tcpip.LinkAddress, tcpip.NetworkProtocolNumber, *stack.PacketBuffer) {
+	d.count++
+}
+
+func (d *counterDispatcher) DeliverOutboundPacket(tcpip.LinkAddress, tcpip.LinkAddress, tcpip.NetworkProtocolNumber, *stack.PacketBuffer) {
+	panic("unimplemented")
+}
+
+func TestNestedLinkEndpoint(t *testing.T) {
+	const emptyAddress = tcpip.LinkAddress("")
+
+	var (
+		childEP  childEndpoint
+		nestedEP parentEndpoint
+		disp     counterDispatcher
+	)
+	nestedEP.Endpoint.Init(&childEP, &nestedEP)
+
+	if childEP.IsAttached() {
+		t.Error("On init, childEP.IsAttached() = true, want = false")
+	}
+	if nestedEP.IsAttached() {
+		t.Error("On init, nestedEP.IsAttached() = true, want = false")
+	}
+
+	nestedEP.Attach(&disp)
+	if disp.count != 0 {
+		t.Fatalf("After attach, got disp.count = %d, want = 0", disp.count)
+	}
+	if !childEP.IsAttached() {
+		t.Error("After attach, childEP.IsAttached() = false, want = true")
+	}
+	if !nestedEP.IsAttached() {
+		t.Error("After attach, nestedEP.IsAttached() = false, want = true")
+	}
+
+	nestedEP.DeliverNetworkPacket(emptyAddress, emptyAddress, header.IPv4ProtocolNumber, stack.NewPacketBuffer(stack.PacketBufferOptions{}))
+	if disp.count != 1 {
+		t.Errorf("After first packet with dispatcher attached, got disp.count = %d, want = 1", disp.count)
+	}
+
+	nestedEP.Attach(nil)
+	if childEP.IsAttached() {
+		t.Error("After detach, childEP.IsAttached() = true, want = false")
+	}
+	if nestedEP.IsAttached() {
+		t.Error("After detach, nestedEP.IsAttached() = true, want = false")
+	}
+
+	disp.count = 0
+	nestedEP.DeliverNetworkPacket(emptyAddress, emptyAddress, header.IPv4ProtocolNumber, stack.NewPacketBuffer(stack.PacketBufferOptions{}))
+	if disp.count != 0 {
+		t.Errorf("After second packet with dispatcher detached, got disp.count = %d, want = 0", disp.count)
+	}
+
+}