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-rw-r--r--pkg/tcpip/header/ipv6.go25
-rw-r--r--pkg/tcpip/network/ipv6/BUILD2
-rw-r--r--pkg/tcpip/network/ipv6/icmp_test.go6
-rw-r--r--pkg/tcpip/network/ipv6/ipv6_test.go258
-rw-r--r--pkg/tcpip/stack/nic.go71
-rw-r--r--pkg/tcpip/stack/stack.go6
6 files changed, 353 insertions, 15 deletions
diff --git a/pkg/tcpip/header/ipv6.go b/pkg/tcpip/header/ipv6.go
index 093850e25..9d3abc0e4 100644
--- a/pkg/tcpip/header/ipv6.go
+++ b/pkg/tcpip/header/ipv6.go
@@ -76,6 +76,13 @@ const (
// IPv6Version is the version of the ipv6 protocol.
IPv6Version = 6
+ // IPv6AllNodesMulticastAddress is a link-local multicast group that
+ // all IPv6 nodes MUST join, as per RFC 4291, section 2.8. Packets
+ // destined to this address will reach all nodes on a link.
+ //
+ // The address is ff02::1.
+ IPv6AllNodesMulticastAddress tcpip.Address = "\xff\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01"
+
// IPv6MinimumMTU is the minimum MTU required by IPv6, per RFC 2460,
// section 5.
IPv6MinimumMTU = 1280
@@ -221,6 +228,24 @@ func IsV6MulticastAddress(addr tcpip.Address) bool {
return addr[0] == 0xff
}
+// IsV6UnicastAddress determines if the provided address is a valid IPv6
+// unicast (and specified) address. That is, IsV6UnicastAddress returns
+// true if addr contains IPv6AddressSize bytes, is not the unspecified
+// address and is not a multicast address.
+func IsV6UnicastAddress(addr tcpip.Address) bool {
+ if len(addr) != IPv6AddressSize {
+ return false
+ }
+
+ // Must not be unspecified
+ if addr == IPv6Any {
+ return false
+ }
+
+ // Return if not a multicast.
+ return addr[0] != 0xff
+}
+
// SolicitedNodeAddr computes the solicited-node multicast address. This is
// used for NDP. Described in RFC 4291. The argument must be a full-length IPv6
// address.
diff --git a/pkg/tcpip/network/ipv6/BUILD b/pkg/tcpip/network/ipv6/BUILD
index a471abbfb..f06622a8b 100644
--- a/pkg/tcpip/network/ipv6/BUILD
+++ b/pkg/tcpip/network/ipv6/BUILD
@@ -26,6 +26,7 @@ go_test(
size = "small",
srcs = [
"icmp_test.go",
+ "ipv6_test.go",
"ndp_test.go",
],
embed = [":ipv6"],
@@ -37,6 +38,7 @@ go_test(
"//pkg/tcpip/link/sniffer",
"//pkg/tcpip/stack",
"//pkg/tcpip/transport/icmp",
+ "//pkg/tcpip/transport/udp",
"//pkg/waiter",
],
)
diff --git a/pkg/tcpip/network/ipv6/icmp_test.go b/pkg/tcpip/network/ipv6/icmp_test.go
index a6a1a5232..653d984e9 100644
--- a/pkg/tcpip/network/ipv6/icmp_test.go
+++ b/pkg/tcpip/network/ipv6/icmp_test.go
@@ -222,9 +222,6 @@ func newTestContext(t *testing.T) *testContext {
if err := c.s0.AddAddress(1, ProtocolNumber, lladdr0); err != nil {
t.Fatalf("AddAddress lladdr0: %v", err)
}
- if err := c.s0.AddAddress(1, ProtocolNumber, header.SolicitedNodeAddr(lladdr0)); err != nil {
- t.Fatalf("AddAddress sn lladdr0: %v", err)
- }
c.linkEP1 = channel.New(256, defaultMTU, linkAddr1)
wrappedEP1 := stack.LinkEndpoint(endpointWithResolutionCapability{LinkEndpoint: c.linkEP1})
@@ -234,9 +231,6 @@ func newTestContext(t *testing.T) *testContext {
if err := c.s1.AddAddress(1, ProtocolNumber, lladdr1); err != nil {
t.Fatalf("AddAddress lladdr1: %v", err)
}
- if err := c.s1.AddAddress(1, ProtocolNumber, header.SolicitedNodeAddr(lladdr1)); err != nil {
- t.Fatalf("AddAddress sn lladdr1: %v", err)
- }
subnet0, err := tcpip.NewSubnet(lladdr1, tcpip.AddressMask(strings.Repeat("\xff", len(lladdr1))))
if err != nil {
diff --git a/pkg/tcpip/network/ipv6/ipv6_test.go b/pkg/tcpip/network/ipv6/ipv6_test.go
new file mode 100644
index 000000000..57bcd5455
--- /dev/null
+++ b/pkg/tcpip/network/ipv6/ipv6_test.go
@@ -0,0 +1,258 @@
+// 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 ipv6
+
+import (
+ "testing"
+
+ "gvisor.dev/gvisor/pkg/tcpip"
+ "gvisor.dev/gvisor/pkg/tcpip/buffer"
+ "gvisor.dev/gvisor/pkg/tcpip/header"
+ "gvisor.dev/gvisor/pkg/tcpip/link/channel"
+ "gvisor.dev/gvisor/pkg/tcpip/stack"
+ "gvisor.dev/gvisor/pkg/tcpip/transport/icmp"
+ "gvisor.dev/gvisor/pkg/tcpip/transport/udp"
+ "gvisor.dev/gvisor/pkg/waiter"
+)
+
+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"
+ // The least significant 3 bytes are the same as addr2 so both addr2 and
+ // addr3 will have the same solicited-node address.
+ addr3 = "\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x02"
+)
+
+// testReceiveICMP tests receiving an ICMP packet from src to dst. want is the
+// expected Neighbor Advertisement received count after receiving the packet.
+func testReceiveICMP(t *testing.T, s *stack.Stack, e *channel.Endpoint, src, dst tcpip.Address, want uint64) {
+ t.Helper()
+
+ // Receive ICMP packet.
+ hdr := buffer.NewPrependable(header.IPv6MinimumSize + header.ICMPv6NeighborAdvertSize)
+ pkt := header.ICMPv6(hdr.Prepend(header.ICMPv6NeighborAdvertSize))
+ pkt.SetType(header.ICMPv6NeighborAdvert)
+ pkt.SetChecksum(header.ICMPv6Checksum(pkt, src, dst, buffer.VectorisedView{}))
+ payloadLength := hdr.UsedLength()
+ ip := header.IPv6(hdr.Prepend(header.IPv6MinimumSize))
+ ip.Encode(&header.IPv6Fields{
+ PayloadLength: uint16(payloadLength),
+ NextHeader: uint8(header.ICMPv6ProtocolNumber),
+ HopLimit: 255,
+ SrcAddr: src,
+ DstAddr: dst,
+ })
+
+ e.Inject(ProtocolNumber, hdr.View().ToVectorisedView())
+
+ stats := s.Stats().ICMP.V6PacketsReceived
+
+ if got := stats.NeighborAdvert.Value(); got != want {
+ t.Fatalf("got NeighborAdvert = %d, want = %d", got, want)
+ }
+}
+
+// testReceiveICMP tests receiving a UDP packet from src to dst. want is the
+// expected UDP received count after receiving the packet.
+func testReceiveUDP(t *testing.T, s *stack.Stack, e *channel.Endpoint, src, dst tcpip.Address, want uint64) {
+ t.Helper()
+
+ wq := waiter.Queue{}
+ we, ch := waiter.NewChannelEntry(nil)
+ wq.EventRegister(&we, waiter.EventIn)
+ defer wq.EventUnregister(&we)
+ defer close(ch)
+
+ ep, err := s.NewEndpoint(udp.ProtocolNumber, ProtocolNumber, &wq)
+ if err != nil {
+ t.Fatalf("NewEndpoint failed: %v", err)
+ }
+ defer ep.Close()
+
+ if err := ep.Bind(tcpip.FullAddress{Addr: dst, Port: 80}); err != nil {
+ t.Fatalf("ep.Bind(...) failed: %v", err)
+ }
+
+ // Receive UDP Packet.
+ hdr := buffer.NewPrependable(header.IPv6MinimumSize + header.UDPMinimumSize)
+ u := header.UDP(hdr.Prepend(header.UDPMinimumSize))
+ u.Encode(&header.UDPFields{
+ SrcPort: 5555,
+ DstPort: 80,
+ Length: header.UDPMinimumSize,
+ })
+
+ // UDP pseudo-header checksum.
+ sum := header.PseudoHeaderChecksum(udp.ProtocolNumber, src, dst, header.UDPMinimumSize)
+
+ // UDP checksum
+ sum = header.Checksum(header.UDP([]byte{}), sum)
+ u.SetChecksum(^u.CalculateChecksum(sum))
+
+ payloadLength := hdr.UsedLength()
+ ip := header.IPv6(hdr.Prepend(header.IPv6MinimumSize))
+ ip.Encode(&header.IPv6Fields{
+ PayloadLength: uint16(payloadLength),
+ NextHeader: uint8(udp.ProtocolNumber),
+ HopLimit: 255,
+ SrcAddr: src,
+ DstAddr: dst,
+ })
+
+ e.Inject(ProtocolNumber, hdr.View().ToVectorisedView())
+
+ stat := s.Stats().UDP.PacketsReceived
+
+ if got := stat.Value(); got != want {
+ t.Fatalf("got UDPPacketsReceived = %d, want = %d", got, want)
+ }
+}
+
+// TestReceiveOnAllNodesMulticastAddr tests that IPv6 endpoints receive ICMP and
+// UDP packets destined to the IPv6 link-local all-nodes multicast address.
+func TestReceiveOnAllNodesMulticastAddr(t *testing.T) {
+ tests := []struct {
+ name string
+ protocolName string
+ rxf func(t *testing.T, s *stack.Stack, e *channel.Endpoint, src, dst tcpip.Address, want uint64)
+ }{
+ {"ICMP", icmp.ProtocolName6, testReceiveICMP},
+ {"UDP", udp.ProtocolName, testReceiveUDP},
+ }
+
+ for _, test := range tests {
+ t.Run(test.name, func(t *testing.T) {
+ s := stack.New([]string{ProtocolName}, []string{test.protocolName}, stack.Options{})
+ e := channel.New(10, 1280, linkAddr1)
+ if err := s.CreateNIC(1, e); err != nil {
+ t.Fatalf("CreateNIC(_) = %s", err)
+ }
+
+ // Should receive a packet destined to the all-nodes
+ // multicast address.
+ test.rxf(t, s, e, addr1, header.IPv6AllNodesMulticastAddress, 1)
+ })
+ }
+}
+
+// TestReceiveOnSolicitedNodeAddr tests that IPv6 endpoints receive ICMP and UDP
+// packets destined to the IPv6 solicited-node address of an assigned IPv6
+// address.
+func TestReceiveOnSolicitedNodeAddr(t *testing.T) {
+ tests := []struct {
+ name string
+ protocolName string
+ rxf func(t *testing.T, s *stack.Stack, e *channel.Endpoint, src, dst tcpip.Address, want uint64)
+ }{
+ {"ICMP", icmp.ProtocolName6, testReceiveICMP},
+ {"UDP", udp.ProtocolName, testReceiveUDP},
+ }
+
+ snmc := header.SolicitedNodeAddr(addr2)
+
+ for _, test := range tests {
+ t.Run(test.name, func(t *testing.T) {
+ s := stack.New([]string{ProtocolName}, []string{test.protocolName}, stack.Options{})
+ e := channel.New(10, 1280, linkAddr1)
+ if err := s.CreateNIC(1, e); err != nil {
+ t.Fatalf("CreateNIC(_) = %s", err)
+ }
+
+ // Should not receive a packet destined to the solicited
+ // node address of addr2/addr3 yet as we haven't added
+ // those addresses.
+ test.rxf(t, s, e, addr1, snmc, 0)
+
+ if err := s.AddAddress(1, ProtocolNumber, addr2); err != nil {
+ t.Fatalf("AddAddress(_, %d, %s) = %s", ProtocolNumber, addr2, err)
+ }
+
+ // Should receive a packet destined to the solicited
+ // node address of addr2/addr3 now that we have added
+ // added addr2.
+ test.rxf(t, s, e, addr1, snmc, 1)
+
+ if err := s.AddAddress(1, ProtocolNumber, addr3); err != nil {
+ t.Fatalf("AddAddress(_, %d, %s) = %s", ProtocolNumber, addr3, err)
+ }
+
+ // Should still receive a packet destined to the
+ // solicited node address of addr2/addr3 now that we
+ // have added addr3.
+ test.rxf(t, s, e, addr1, snmc, 2)
+
+ if err := s.RemoveAddress(1, addr2); err != nil {
+ t.Fatalf("RemoveAddress(_, %s) = %s", addr2, err)
+ }
+
+ // Should still receive a packet destined to the
+ // solicited node address of addr2/addr3 now that we
+ // have removed addr2.
+ test.rxf(t, s, e, addr1, snmc, 3)
+
+ if err := s.RemoveAddress(1, addr3); err != nil {
+ t.Fatalf("RemoveAddress(_, %s) = %s", addr3, err)
+ }
+
+ // Should not receive a packet destined to the solicited
+ // node address of addr2/addr3 yet as both of them got
+ // removed.
+ test.rxf(t, s, e, addr1, snmc, 3)
+ })
+ }
+}
+
+// TestAddIpv6Address tests adding IPv6 addresses.
+func TestAddIpv6Address(t *testing.T) {
+ tests := []struct {
+ name string
+ addr tcpip.Address
+ }{
+ // This test is in response to b/140943433.
+ {
+ "Nil",
+ tcpip.Address([]byte(nil)),
+ },
+ {
+ "ValidUnicast",
+ addr1,
+ },
+ {
+ "ValidLinkLocalUnicast",
+ lladdr0,
+ },
+ }
+
+ for _, test := range tests {
+ t.Run(test.name, func(t *testing.T) {
+ s := stack.New([]string{ProtocolName}, nil, stack.Options{})
+ if err := s.CreateNIC(1, &stubLinkEndpoint{}); err != nil {
+ t.Fatalf("CreateNIC(_) = %s", err)
+ }
+
+ if err := s.AddAddress(1, ProtocolNumber, test.addr); err != nil {
+ t.Fatalf("AddAddress(_, %d, nil) = %s", ProtocolNumber, err)
+ }
+
+ addr, err := s.GetMainNICAddress(1, header.IPv6ProtocolNumber)
+ if err != nil {
+ t.Fatalf("stack.GetMainNICAddress(_, _) err = %s", err)
+ }
+ if addr.Address != test.addr {
+ t.Fatalf("got stack.GetMainNICAddress(_, _) = %s, want = %s", addr.Address, test.addr)
+ }
+ })
+ }
+}
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go
index 43719085e..a719058b4 100644
--- a/pkg/tcpip/stack/nic.go
+++ b/pkg/tcpip/stack/nic.go
@@ -102,6 +102,25 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, loopback
}
}
+// enable enables the NIC. enable will attach the link to its LinkEndpoint and
+// join the IPv6 All-Nodes Multicast address (ff02::1).
+func (n *NIC) enable() *tcpip.Error {
+ n.attachLinkEndpoint()
+
+ // Join the IPv6 All-Nodes Multicast group if the stack is configured to
+ // use IPv6. This is required to ensure that this node properly receives
+ // and responds to the various NDP messages that are destined to the
+ // all-nodes multicast address. An example is the Neighbor Advertisement
+ // when we perform Duplicate Address Detection, or Router Advertisement
+ // when we do Router Discovery. See RFC 4862, section 5.4.2 and RFC 4861
+ // section 4.2 for more information.
+ if _, ok := n.stack.networkProtocols[header.IPv6ProtocolNumber]; ok {
+ return n.joinGroup(header.IPv6ProtocolNumber, header.IPv6AllNodesMulticastAddress)
+ }
+
+ return nil
+}
+
// attachLinkEndpoint attaches the NIC to the endpoint, which will enable it
// to start delivering packets.
func (n *NIC) attachLinkEndpoint() {
@@ -307,6 +326,8 @@ func (n *NIC) addPermanentAddressLocked(protocolAddress tcpip.ProtocolAddress, p
}
func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior, kind networkEndpointKind) (*referencedNetworkEndpoint, *tcpip.Error) {
+ // TODO(b/141022673): Validate IP address before adding them.
+
// Sanity check.
id := NetworkEndpointID{protocolAddress.AddressWithPrefix.Address}
if _, ok := n.endpoints[id]; ok {
@@ -339,6 +360,15 @@ func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb Primar
}
}
+ // If we are adding an IPv6 unicast address, join the solicited-node
+ // multicast address.
+ if protocolAddress.Protocol == header.IPv6ProtocolNumber && header.IsV6UnicastAddress(protocolAddress.AddressWithPrefix.Address) {
+ snmc := header.SolicitedNodeAddr(protocolAddress.AddressWithPrefix.Address)
+ if err := n.joinGroupLocked(protocolAddress.Protocol, snmc); err != nil {
+ return nil, err
+ }
+ }
+
n.endpoints[id] = ref
l, ok := n.primary[protocolAddress.Protocol]
@@ -467,13 +497,27 @@ func (n *NIC) removeEndpoint(r *referencedNetworkEndpoint) {
}
func (n *NIC) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error {
- r := n.endpoints[NetworkEndpointID{addr}]
- if r == nil || r.getKind() != permanent {
+ r, ok := n.endpoints[NetworkEndpointID{addr}]
+ if !ok || r.getKind() != permanent {
return tcpip.ErrBadLocalAddress
}
r.setKind(permanentExpired)
- r.decRefLocked()
+ if !r.decRefLocked() {
+ // The endpoint still has references to it.
+ return nil
+ }
+
+ // At this point the endpoint is deleted.
+
+ // If we are removing an IPv6 unicast address, leave the solicited-node
+ // multicast address.
+ if r.protocol == header.IPv6ProtocolNumber && header.IsV6UnicastAddress(addr) {
+ snmc := header.SolicitedNodeAddr(addr)
+ if err := n.leaveGroupLocked(snmc); err != nil {
+ return err
+ }
+ }
return nil
}
@@ -491,6 +535,13 @@ func (n *NIC) joinGroup(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address
n.mu.Lock()
defer n.mu.Unlock()
+ return n.joinGroupLocked(protocol, addr)
+}
+
+// joinGroupLocked adds a new endpoint for the given multicast address, if none
+// exists yet. Otherwise it just increments its count. n MUST be locked before
+// joinGroupLocked is called.
+func (n *NIC) joinGroupLocked(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address) *tcpip.Error {
id := NetworkEndpointID{addr}
joins := n.mcastJoins[id]
if joins == 0 {
@@ -518,6 +569,13 @@ func (n *NIC) leaveGroup(addr tcpip.Address) *tcpip.Error {
n.mu.Lock()
defer n.mu.Unlock()
+ return n.leaveGroupLocked(addr)
+}
+
+// leaveGroupLocked decrements the count for the given multicast address, and
+// when it reaches zero removes the endpoint for this address. n MUST be locked
+// before leaveGroupLocked is called.
+func (n *NIC) leaveGroupLocked(addr tcpip.Address) *tcpip.Error {
id := NetworkEndpointID{addr}
joins := n.mcastJoins[id]
switch joins {
@@ -802,11 +860,14 @@ func (r *referencedNetworkEndpoint) decRef() {
}
// decRefLocked is the same as decRef but assumes that the NIC.mu mutex is
-// locked.
-func (r *referencedNetworkEndpoint) decRefLocked() {
+// locked. Returns true if the endpoint was removed.
+func (r *referencedNetworkEndpoint) decRefLocked() bool {
if atomic.AddInt32(&r.refs, -1) == 0 {
r.nic.removeEndpointLocked(r)
+ return true
}
+
+ return false
}
// incRef increments the ref count. It must only be called when the caller is
diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go
index a961e8ebe..1fe21b68e 100644
--- a/pkg/tcpip/stack/stack.go
+++ b/pkg/tcpip/stack/stack.go
@@ -633,7 +633,7 @@ func (s *Stack) createNIC(id tcpip.NICID, name string, ep LinkEndpoint, enabled,
s.nics[id] = n
if enabled {
- n.attachLinkEndpoint()
+ return n.enable()
}
return nil
@@ -680,9 +680,7 @@ func (s *Stack) EnableNIC(id tcpip.NICID) *tcpip.Error {
return tcpip.ErrUnknownNICID
}
- nic.attachLinkEndpoint()
-
- return nil
+ return nic.enable()
}
// CheckNIC checks if a NIC is usable.
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 21:19:15 +0000