diff options
Diffstat (limited to 'pkg/tcpip/stack/ndp_test.go')
-rw-r--r-- | pkg/tcpip/stack/ndp_test.go | 352 |
1 files changed, 352 insertions, 0 deletions
diff --git a/pkg/tcpip/stack/ndp_test.go b/pkg/tcpip/stack/ndp_test.go new file mode 100644 index 000000000..cc789d70f --- /dev/null +++ b/pkg/tcpip/stack/ndp_test.go @@ -0,0 +1,352 @@ +// Copyright 2019 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 stack_test + +import ( + "testing" + "time" + + "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/buffer" + "gvisor.dev/gvisor/pkg/tcpip/checker" + "gvisor.dev/gvisor/pkg/tcpip/header" + "gvisor.dev/gvisor/pkg/tcpip/link/channel" + "gvisor.dev/gvisor/pkg/tcpip/network/ipv6" + "gvisor.dev/gvisor/pkg/tcpip/stack" + "gvisor.dev/gvisor/pkg/tcpip/transport/icmp" +) + +const ( + addr1 = "\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01" + addr2 = "\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02" + linkAddr1 = "\x01\x02\x03\x04\x05\x06" + linkAddr2 = "\x01\x02\x03\x04\x05\x07" +) + +// TestDADDisabled tests that an address successfully resolves immediately +// when DAD is not enabled (the default for an empty stack.Options). +func TestDADDisabled(t *testing.T) { + opts := stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + } + + e := channel.New(10, 1280, linkAddr1) + s := stack.New(opts) + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(_) = %s", err) + } + + if err := s.AddAddress(1, header.IPv6ProtocolNumber, addr1); err != nil { + t.Fatalf("AddAddress(_, %d, %s) = %s", header.IPv6ProtocolNumber, addr1, err) + } + + // Should get the address immediately since we should not have performed + // DAD on it. + addr, err := s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("stack.GetMainNICAddress(_, _) err = %s", err) + } + if addr.Address != addr1 { + t.Fatalf("got stack.GetMainNICAddress(_, _) = %s, want = %s", addr, addr1) + } + + // We should not have sent any NDP NS messages. + if got := s.Stats().ICMP.V6PacketsSent.NeighborSolicit.Value(); got != 0 { + t.Fatalf("got NeighborSolicit = %d, want = 0", got) + } +} + +// TestDADResolve tests that an address successfully resolves after performing +// DAD for various values of DupAddrDetectTransmits and RetransmitTimer. +// Included in the subtests is a test to make sure that an invalid +// RetransmitTimer (<1ms) values get fixed to the default RetransmitTimer of 1s. +func TestDADResolve(t *testing.T) { + tests := []struct { + name string + dupAddrDetectTransmits uint8 + retransTimer time.Duration + expectedRetransmitTimer time.Duration + }{ + {"1:1s:1s", 1, time.Second, time.Second}, + {"2:1s:1s", 2, time.Second, time.Second}, + {"1:2s:2s", 1, 2 * time.Second, 2 * time.Second}, + // 0s is an invalid RetransmitTimer timer and will be fixed to + // the default RetransmitTimer value of 1s. + {"1:0s:1s", 1, 0, time.Second}, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + opts := stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + } + opts.NDPConfigs.RetransmitTimer = test.retransTimer + opts.NDPConfigs.DupAddrDetectTransmits = test.dupAddrDetectTransmits + + e := channel.New(10, 1280, linkAddr1) + s := stack.New(opts) + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(_) = %s", err) + } + + if err := s.AddAddress(1, header.IPv6ProtocolNumber, addr1); err != nil { + t.Fatalf("AddAddress(_, %d, %s) = %s", header.IPv6ProtocolNumber, addr1, err) + } + + stat := s.Stats().ICMP.V6PacketsSent.NeighborSolicit + + // Should have sent an NDP NS almost immediately. + time.Sleep(100 * time.Millisecond) + if got := stat.Value(); got != 1 { + t.Fatalf("got NeighborSolicit = %d, want = 1", got) + + } + + // Address should not be considered bound to the NIC yet + // (DAD ongoing). + addr, err := s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (_, %v), want = (_, nil)", err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + + // Wait for the remaining time - 500ms, to make sure + // the address is still not resolved. Note, we subtract + // 600ms because we already waited for 100ms earlier, + // so our remaining time is 100ms less than the expected + // time. + // (X - 100ms) - 500ms = X - 600ms + // + // TODO(b/140896005): Use events from the netstack to + // be signalled before DAD resolves. + time.Sleep(test.expectedRetransmitTimer*time.Duration(test.dupAddrDetectTransmits) - 600*time.Millisecond) + addr, err = s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (_, %v), want = (_, nil)", err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + + // Wait for the remaining time + 250ms, at which point + // the address should be resolved. Note, the remaining + // time is 500ms. See above comments. + // + // TODO(b/140896005): Use events from the netstack to + // know immediately when DAD completes. + time.Sleep(750 * time.Millisecond) + addr, err = s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("stack.GetMainNICAddress(_, _) err = %s", err) + } + if addr.Address != addr1 { + t.Fatalf("got stack.GetMainNICAddress(_, _) = %s, want = %s", addr, addr1) + } + + // Should not have sent any more NS messages. + if got := stat.Value(); got != uint64(test.dupAddrDetectTransmits) { + t.Fatalf("got NeighborSolicit = %d, want = %d", got, test.dupAddrDetectTransmits) + } + + // Validate the sent Neighbor Solicitation messages. + for i := uint8(0); i < test.dupAddrDetectTransmits; i++ { + p := <-e.C + + // Make sure its an IPv6 packet. + if p.Proto != header.IPv6ProtocolNumber { + t.Fatalf("got Proto = %d, want = %d", p.Proto, header.IPv6ProtocolNumber) + } + + // Check NDP packet. + checker.IPv6(t, p.Header.ToVectorisedView().First(), + checker.NDPNS( + checker.NDPNSTargetAddress(addr1))) + } + }) + } + +} + +// TestDADFail tests to make sure that the DAD process fails if another node is +// detected to be performing DAD on the same address (receive an NS message from +// a node doing DAD for the same address), or if another node is detected to own +// the address already (receive an NA message for the tentative address). +func TestDADFail(t *testing.T) { + tests := []struct { + name string + makeBuf func(tgt tcpip.Address) buffer.Prependable + getStat func(s tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter + }{ + { + "RxSolicit", + func(tgt tcpip.Address) buffer.Prependable { + hdr := buffer.NewPrependable(header.IPv6MinimumSize + header.ICMPv6NeighborSolicitMinimumSize) + pkt := header.ICMPv6(hdr.Prepend(header.ICMPv6NeighborSolicitMinimumSize)) + pkt.SetType(header.ICMPv6NeighborSolicit) + ns := header.NDPNeighborSolicit(pkt.NDPPayload()) + ns.SetTargetAddress(tgt) + snmc := header.SolicitedNodeAddr(tgt) + pkt.SetChecksum(header.ICMPv6Checksum(pkt, header.IPv6Any, snmc, buffer.VectorisedView{})) + payloadLength := hdr.UsedLength() + ip := header.IPv6(hdr.Prepend(header.IPv6MinimumSize)) + ip.Encode(&header.IPv6Fields{ + PayloadLength: uint16(payloadLength), + NextHeader: uint8(icmp.ProtocolNumber6), + HopLimit: 255, + SrcAddr: header.IPv6Any, + DstAddr: snmc, + }) + + return hdr + + }, + func(s tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter { + return s.NeighborSolicit + }, + }, + { + "RxAdvert", + func(tgt tcpip.Address) buffer.Prependable { + hdr := buffer.NewPrependable(header.IPv6MinimumSize + header.ICMPv6NeighborAdvertSize) + pkt := header.ICMPv6(hdr.Prepend(header.ICMPv6NeighborAdvertSize)) + pkt.SetType(header.ICMPv6NeighborAdvert) + na := header.NDPNeighborAdvert(pkt.NDPPayload()) + na.SetSolicitedFlag(true) + na.SetOverrideFlag(true) + na.SetTargetAddress(tgt) + pkt.SetChecksum(header.ICMPv6Checksum(pkt, tgt, header.IPv6AllNodesMulticastAddress, buffer.VectorisedView{})) + payloadLength := hdr.UsedLength() + ip := header.IPv6(hdr.Prepend(header.IPv6MinimumSize)) + ip.Encode(&header.IPv6Fields{ + PayloadLength: uint16(payloadLength), + NextHeader: uint8(icmp.ProtocolNumber6), + HopLimit: 255, + SrcAddr: tgt, + DstAddr: header.IPv6AllNodesMulticastAddress, + }) + + return hdr + + }, + func(s tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter { + return s.NeighborAdvert + }, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + opts := stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: stack.DefaultNDPConfigurations(), + } + opts.NDPConfigs.RetransmitTimer = time.Second * 2 + + e := channel.New(10, 1280, linkAddr1) + s := stack.New(opts) + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(_) = %s", err) + } + + if err := s.AddAddress(1, header.IPv6ProtocolNumber, addr1); err != nil { + t.Fatalf("AddAddress(_, %d, %s) = %s", header.IPv6ProtocolNumber, addr1, err) + } + + // Address should not be considered bound to the NIC yet + // (DAD ongoing). + addr, err := s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (_, %v), want = (_, nil)", err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + + // Receive a packet to simulate multiple nodes owning or + // attempting to own the same address. + hdr := test.makeBuf(addr1) + e.Inject(header.IPv6ProtocolNumber, hdr.View().ToVectorisedView()) + + stat := test.getStat(s.Stats().ICMP.V6PacketsReceived) + if got := stat.Value(); got != 1 { + t.Fatalf("got stat = %d, want = 1", got) + } + + // Wait 3 seconds to make sure that DAD did not resolve + time.Sleep(3 * time.Second) + addr, err = s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (_, %v), want = (_, nil)", err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + }) + } +} + +// TestDADStop tests to make sure that the DAD process stops when an address is +// removed. +func TestDADStop(t *testing.T) { + opts := stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + } + opts.NDPConfigs.RetransmitTimer = time.Second + opts.NDPConfigs.DupAddrDetectTransmits = 2 + + e := channel.New(10, 1280, linkAddr1) + s := stack.New(opts) + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(_) = %s", err) + } + + if err := s.AddAddress(1, header.IPv6ProtocolNumber, addr1); err != nil { + t.Fatalf("AddAddress(_, %d, %s) = %s", header.IPv6ProtocolNumber, addr1, err) + } + + // Address should not be considered bound to the NIC yet (DAD ongoing). + addr, err := s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (_, %v), want = (_, nil)", err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + + // Remove the address. This should stop DAD. + if err := s.RemoveAddress(1, addr1); err != nil { + t.Fatalf("RemoveAddress(_, %s) = %s", addr1, err) + } + + // Wait for the time to normally resolve + // DupAddrDetectTransmits(2) * RetransmitTimer(1s) = 2s. + // An extra 250ms is added to make sure that if DAD was still running + // it resolves and the check below fails. + time.Sleep(2*time.Second + 250*time.Millisecond) + addr, err = s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (_, %v), want = (_, nil)", err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + + // Should not have sent more than 1 NS message. + if got := s.Stats().ICMP.V6PacketsSent.NeighborSolicit.Value(); got > 1 { + t.Fatalf("got NeighborSolicit = %d, want <= 1", got) + } +} |