1 files changed, 138 insertions, 0 deletions
diff --git a/pkg/tcpip/network/arp/arp_test.go b/pkg/tcpip/network/arp/arp_test.go
new file mode 100644
index 000000000..91ffdce4b
--- /dev/null
+++ b/pkg/tcpip/network/arp/arp_test.go
@@ -0,0 +1,138 @@
+// Copyright 2016 The Netstack Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package arp_test
+
+import (
+	"testing"
+	"time"
+
+	"gvisor.googlesource.com/gvisor/pkg/tcpip"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/buffer"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/header"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/link/channel"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/link/sniffer"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/network/arp"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/network/ipv4"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/stack"
+)
+
+const (
+	stackLinkAddr = tcpip.LinkAddress("\x0a\x0a\x0b\x0b\x0c\x0c")
+	stackAddr1    = tcpip.Address("\x0a\x00\x00\x01")
+	stackAddr2    = tcpip.Address("\x0a\x00\x00\x02")
+	stackAddrBad  = tcpip.Address("\x0a\x00\x00\x03")
+)
+
+type testContext struct {
+	t      *testing.T
+	linkEP *channel.Endpoint
+	s      *stack.Stack
+}
+
+func newTestContext(t *testing.T) *testContext {
+	s := stack.New([]string{ipv4.ProtocolName, arp.ProtocolName}, []string{ipv4.PingProtocolName})
+
+	const defaultMTU = 65536
+	id, linkEP := channel.New(256, defaultMTU, stackLinkAddr)
+	if testing.Verbose() {
+		id = sniffer.New(id)
+	}
+	if err := s.CreateNIC(1, id); err != nil {
+		t.Fatalf("CreateNIC failed: %v", err)
+	}
+
+	if err := s.AddAddress(1, ipv4.ProtocolNumber, stackAddr1); err != nil {
+		t.Fatalf("AddAddress for ipv4 failed: %v", err)
+	}
+	if err := s.AddAddress(1, ipv4.ProtocolNumber, stackAddr2); err != nil {
+		t.Fatalf("AddAddress for ipv4 failed: %v", err)
+	}
+	if err := s.AddAddress(1, arp.ProtocolNumber, arp.ProtocolAddress); err != nil {
+		t.Fatalf("AddAddress for arp failed: %v", err)
+	}
+
+	s.SetRouteTable([]tcpip.Route{{
+		Destination: "\x00\x00\x00\x00",
+		Mask:        "\x00\x00\x00\x00",
+		Gateway:     "",
+		NIC:         1,
+	}})
+
+	return &testContext{
+		t:      t,
+		s:      s,
+		linkEP: linkEP,
+	}
+}
+
+func (c *testContext) cleanup() {
+	close(c.linkEP.C)
+}
+
+func TestDirectRequest(t *testing.T) {
+	c := newTestContext(t)
+	defer c.cleanup()
+
+	const senderMAC = "\x01\x02\x03\x04\x05\x06"
+	const senderIPv4 = "\x0a\x00\x00\x02"
+
+	v := make(buffer.View, header.ARPSize)
+	h := header.ARP(v)
+	h.SetIPv4OverEthernet()
+	h.SetOp(header.ARPRequest)
+	copy(h.HardwareAddressSender(), senderMAC)
+	copy(h.ProtocolAddressSender(), senderIPv4)
+
+	// stackAddr1
+	copy(h.ProtocolAddressTarget(), stackAddr1)
+	vv := v.ToVectorisedView([1]buffer.View{})
+	c.linkEP.Inject(arp.ProtocolNumber, &vv)
+	pkt := <-c.linkEP.C
+	if pkt.Proto != arp.ProtocolNumber {
+		t.Fatalf("stackAddr1: expected ARP response, got network protocol number %v", pkt.Proto)
+	}
+	rep := header.ARP(pkt.Header)
+	if !rep.IsValid() {
+		t.Fatalf("stackAddr1: invalid ARP response len(pkt.Header)=%d", len(pkt.Header))
+	}
+	if tcpip.Address(rep.ProtocolAddressSender()) != stackAddr1 {
+		t.Errorf("stackAddr1: expected sender to be set")
+	}
+	if got := tcpip.LinkAddress(rep.HardwareAddressSender()); got != stackLinkAddr {
+		t.Errorf("stackAddr1: expected sender to be stackLinkAddr, got %q", got)
+	}
+
+	// stackAddr2
+	copy(h.ProtocolAddressTarget(), stackAddr2)
+	vv = v.ToVectorisedView([1]buffer.View{})
+	c.linkEP.Inject(arp.ProtocolNumber, &vv)
+	pkt = <-c.linkEP.C
+	if pkt.Proto != arp.ProtocolNumber {
+		t.Fatalf("stackAddr2: expected ARP response, got network protocol number %v", pkt.Proto)
+	}
+	rep = header.ARP(pkt.Header)
+	if !rep.IsValid() {
+		t.Fatalf("stackAddr2: invalid ARP response len(pkt.Header)=%d", len(pkt.Header))
+	}
+	if tcpip.Address(rep.ProtocolAddressSender()) != stackAddr2 {
+		t.Errorf("stackAddr2: expected sender to be set")
+	}
+	if got := tcpip.LinkAddress(rep.HardwareAddressSender()); got != stackLinkAddr {
+		t.Errorf("stackAddr2: expected sender to be stackLinkAddr, got %q", got)
+	}
+
+	// stackAddrBad
+	copy(h.ProtocolAddressTarget(), stackAddrBad)
+	vv = v.ToVectorisedView([1]buffer.View{})
+	c.linkEP.Inject(arp.ProtocolNumber, &vv)
+	select {
+	case pkt := <-c.linkEP.C:
+		t.Errorf("stackAddrBad: unexpected packet sent, Proto=%v", pkt.Proto)
+	case <-time.After(100 * time.Millisecond):
+		// Sleep tests are gross, but this will only
+		// potentially fail flakily if there's a bugj
+		// If there is no bug this will reliably succeed.
+	}
+}