diff options
Diffstat (limited to 'pkg/tcpip/stack')
| -rw-r--r-- | pkg/tcpip/stack/BUILD | 12 | ||||
| -rw-r--r-- | pkg/tcpip/stack/dhcpv6configurationfromndpra_string.go | 39 | ||||
| -rw-r--r-- | pkg/tcpip/stack/forwarder.go | 131 | ||||
| -rw-r--r-- | pkg/tcpip/stack/forwarder_test.go | 635 | ||||
| -rw-r--r-- | pkg/tcpip/stack/iptables.go | 311 | ||||
| -rw-r--r-- | pkg/tcpip/stack/iptables_targets.go | 144 | ||||
| -rw-r--r-- | pkg/tcpip/stack/iptables_types.go | 180 | ||||
| -rw-r--r-- | pkg/tcpip/stack/ndp.go | 329 | ||||
| -rw-r--r-- | pkg/tcpip/stack/ndp_test.go | 207 | ||||
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 185 | ||||
| -rw-r--r-- | pkg/tcpip/stack/nic_test.go | 3 | ||||
| -rw-r--r-- | pkg/tcpip/stack/packet_buffer.go | 71 | ||||
| -rw-r--r-- | pkg/tcpip/stack/packet_buffer_state.go | 27 | ||||
| -rw-r--r-- | pkg/tcpip/stack/rand.go | 40 | ||||
| -rw-r--r-- | pkg/tcpip/stack/registration.go | 35 | ||||
| -rw-r--r-- | pkg/tcpip/stack/route.go | 6 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack.go | 72 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack_test.go | 546 | ||||
| -rw-r--r-- | pkg/tcpip/stack/transport_demuxer.go | 281 | ||||
| -rw-r--r-- | pkg/tcpip/stack/transport_demuxer_test.go | 16 | ||||
| -rw-r--r-- | pkg/tcpip/stack/transport_test.go | 27 |
21 files changed, 2632 insertions, 665 deletions
diff --git a/pkg/tcpip/stack/BUILD b/pkg/tcpip/stack/BUILD index 705cf01ee..8d80e9cee 100644 --- a/pkg/tcpip/stack/BUILD +++ b/pkg/tcpip/stack/BUILD @@ -18,11 +18,19 @@ go_template_instance( go_library( name = "stack", srcs = [ + "dhcpv6configurationfromndpra_string.go", + "forwarder.go", "icmp_rate_limit.go", + "iptables.go", + "iptables_targets.go", + "iptables_types.go", "linkaddrcache.go", "linkaddrentry_list.go", "ndp.go", "nic.go", + "packet_buffer.go", + "packet_buffer_state.go", + "rand.go", "registration.go", "route.go", "stack.go", @@ -32,6 +40,7 @@ go_library( visibility = ["//visibility:public"], deps = [ "//pkg/ilist", + "//pkg/log", "//pkg/rand", "//pkg/sleep", "//pkg/sync", @@ -39,7 +48,6 @@ go_library( "//pkg/tcpip/buffer", "//pkg/tcpip/hash/jenkins", "//pkg/tcpip/header", - "//pkg/tcpip/iptables", "//pkg/tcpip/ports", "//pkg/tcpip/seqnum", "//pkg/waiter", @@ -63,7 +71,6 @@ go_test( "//pkg/tcpip/buffer", "//pkg/tcpip/checker", "//pkg/tcpip/header", - "//pkg/tcpip/iptables", "//pkg/tcpip/link/channel", "//pkg/tcpip/link/loopback", "//pkg/tcpip/network/ipv4", @@ -79,6 +86,7 @@ go_test( name = "stack_test", size = "small", srcs = [ + "forwarder_test.go", "linkaddrcache_test.go", "nic_test.go", ], diff --git a/pkg/tcpip/stack/dhcpv6configurationfromndpra_string.go b/pkg/tcpip/stack/dhcpv6configurationfromndpra_string.go new file mode 100644 index 000000000..8b4213eec --- /dev/null +++ b/pkg/tcpip/stack/dhcpv6configurationfromndpra_string.go @@ -0,0 +1,39 @@ +// 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. + +// Code generated by "stringer -type=DHCPv6ConfigurationFromNDPRA"; DO NOT EDIT. + +package stack + +import "strconv" + +func _() { + // An "invalid array index" compiler error signifies that the constant values have changed. + // Re-run the stringer command to generate them again. + var x [1]struct{} + _ = x[DHCPv6NoConfiguration-0] + _ = x[DHCPv6ManagedAddress-1] + _ = x[DHCPv6OtherConfigurations-2] +} + +const _DHCPv6ConfigurationFromNDPRA_name = "DHCPv6NoConfigurationDHCPv6ManagedAddressDHCPv6OtherConfigurations" + +var _DHCPv6ConfigurationFromNDPRA_index = [...]uint8{0, 21, 41, 66} + +func (i DHCPv6ConfigurationFromNDPRA) String() string { + if i < 0 || i >= DHCPv6ConfigurationFromNDPRA(len(_DHCPv6ConfigurationFromNDPRA_index)-1) { + return "DHCPv6ConfigurationFromNDPRA(" + strconv.FormatInt(int64(i), 10) + ")" + } + return _DHCPv6ConfigurationFromNDPRA_name[_DHCPv6ConfigurationFromNDPRA_index[i]:_DHCPv6ConfigurationFromNDPRA_index[i+1]] +} diff --git a/pkg/tcpip/stack/forwarder.go b/pkg/tcpip/stack/forwarder.go new file mode 100644 index 000000000..6b64cd37f --- /dev/null +++ b/pkg/tcpip/stack/forwarder.go @@ -0,0 +1,131 @@ +// 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 stack + +import ( + "fmt" + + "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/tcpip" +) + +const ( + // maxPendingResolutions is the maximum number of pending link-address + // resolutions. + maxPendingResolutions = 64 + maxPendingPacketsPerResolution = 256 +) + +type pendingPacket struct { + nic *NIC + route *Route + proto tcpip.NetworkProtocolNumber + pkt PacketBuffer +} + +type forwardQueue struct { + sync.Mutex + + // The packets to send once the resolver completes. + packets map[<-chan struct{}][]*pendingPacket + + // FIFO of channels used to cancel the oldest goroutine waiting for + // link-address resolution. + cancelChans []chan struct{} +} + +func newForwardQueue() *forwardQueue { + return &forwardQueue{packets: make(map[<-chan struct{}][]*pendingPacket)} +} + +func (f *forwardQueue) enqueue(ch <-chan struct{}, n *NIC, r *Route, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) { + shouldWait := false + + f.Lock() + packets, ok := f.packets[ch] + if !ok { + shouldWait = true + } + for len(packets) == maxPendingPacketsPerResolution { + p := packets[0] + packets = packets[1:] + p.nic.stack.stats.IP.OutgoingPacketErrors.Increment() + p.route.Release() + } + if l := len(packets); l >= maxPendingPacketsPerResolution { + panic(fmt.Sprintf("max pending packets for resolution reached; got %d packets, max = %d", l, maxPendingPacketsPerResolution)) + } + f.packets[ch] = append(packets, &pendingPacket{ + nic: n, + route: r, + proto: protocol, + pkt: pkt, + }) + f.Unlock() + + if !shouldWait { + return + } + + // Wait for the link-address resolution to complete. + // Start a goroutine with a forwarding-cancel channel so that we can + // limit the maximum number of goroutines running concurrently. + cancel := f.newCancelChannel() + go func() { + cancelled := false + select { + case <-ch: + case <-cancel: + cancelled = true + } + + f.Lock() + packets := f.packets[ch] + delete(f.packets, ch) + f.Unlock() + + for _, p := range packets { + if cancelled { + p.nic.stack.stats.IP.OutgoingPacketErrors.Increment() + } else if _, err := p.route.Resolve(nil); err != nil { + p.nic.stack.stats.IP.OutgoingPacketErrors.Increment() + } else { + p.nic.forwardPacket(p.route, p.proto, p.pkt) + } + p.route.Release() + } + }() +} + +// newCancelChannel creates a channel that can cancel a pending forwarding +// activity. The oldest channel is closed if the number of open channels would +// exceed maxPendingResolutions. +func (f *forwardQueue) newCancelChannel() chan struct{} { + f.Lock() + defer f.Unlock() + + if len(f.cancelChans) == maxPendingResolutions { + ch := f.cancelChans[0] + f.cancelChans = f.cancelChans[1:] + close(ch) + } + if l := len(f.cancelChans); l >= maxPendingResolutions { + panic(fmt.Sprintf("max pending resolutions reached; got %d active resolutions, max = %d", l, maxPendingResolutions)) + } + + ch := make(chan struct{}) + f.cancelChans = append(f.cancelChans, ch) + return ch +} diff --git a/pkg/tcpip/stack/forwarder_test.go b/pkg/tcpip/stack/forwarder_test.go new file mode 100644 index 000000000..c45c43d21 --- /dev/null +++ b/pkg/tcpip/stack/forwarder_test.go @@ -0,0 +1,635 @@ +// 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 stack + +import ( + "encoding/binary" + "math" + "testing" + "time" + + "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/buffer" +) + +const ( + fwdTestNetNumber tcpip.NetworkProtocolNumber = math.MaxUint32 + fwdTestNetHeaderLen = 12 + fwdTestNetDefaultPrefixLen = 8 + + // fwdTestNetDefaultMTU is the MTU, in bytes, used throughout the tests, + // except where another value is explicitly used. It is chosen to match + // the MTU of loopback interfaces on linux systems. + fwdTestNetDefaultMTU = 65536 +) + +// fwdTestNetworkEndpoint is a network-layer protocol endpoint. +// Headers of this protocol are fwdTestNetHeaderLen bytes, but we currently only +// use the first three: destination address, source address, and transport +// protocol. They're all one byte fields to simplify parsing. +type fwdTestNetworkEndpoint struct { + nicID tcpip.NICID + id NetworkEndpointID + prefixLen int + proto *fwdTestNetworkProtocol + dispatcher TransportDispatcher + ep LinkEndpoint +} + +func (f *fwdTestNetworkEndpoint) MTU() uint32 { + return f.ep.MTU() - uint32(f.MaxHeaderLength()) +} + +func (f *fwdTestNetworkEndpoint) NICID() tcpip.NICID { + return f.nicID +} + +func (f *fwdTestNetworkEndpoint) PrefixLen() int { + return f.prefixLen +} + +func (*fwdTestNetworkEndpoint) DefaultTTL() uint8 { + return 123 +} + +func (f *fwdTestNetworkEndpoint) ID() *NetworkEndpointID { + return &f.id +} + +func (f *fwdTestNetworkEndpoint) HandlePacket(r *Route, pkt PacketBuffer) { + // Consume the network header. + b := pkt.Data.First() + pkt.Data.TrimFront(fwdTestNetHeaderLen) + + // Dispatch the packet to the transport protocol. + f.dispatcher.DeliverTransportPacket(r, tcpip.TransportProtocolNumber(b[2]), pkt) +} + +func (f *fwdTestNetworkEndpoint) MaxHeaderLength() uint16 { + return f.ep.MaxHeaderLength() + fwdTestNetHeaderLen +} + +func (f *fwdTestNetworkEndpoint) PseudoHeaderChecksum(protocol tcpip.TransportProtocolNumber, dstAddr tcpip.Address) uint16 { + return 0 +} + +func (f *fwdTestNetworkEndpoint) Capabilities() LinkEndpointCapabilities { + return f.ep.Capabilities() +} + +func (f *fwdTestNetworkEndpoint) WritePacket(r *Route, gso *GSO, params NetworkHeaderParams, pkt PacketBuffer) *tcpip.Error { + // Add the protocol's header to the packet and send it to the link + // endpoint. + b := pkt.Header.Prepend(fwdTestNetHeaderLen) + b[0] = r.RemoteAddress[0] + b[1] = f.id.LocalAddress[0] + b[2] = byte(params.Protocol) + + return f.ep.WritePacket(r, gso, fwdTestNetNumber, pkt) +} + +// WritePackets implements LinkEndpoint.WritePackets. +func (f *fwdTestNetworkEndpoint) WritePackets(r *Route, gso *GSO, pkts []PacketBuffer, params NetworkHeaderParams) (int, *tcpip.Error) { + panic("not implemented") +} + +func (*fwdTestNetworkEndpoint) WriteHeaderIncludedPacket(r *Route, pkt PacketBuffer) *tcpip.Error { + return tcpip.ErrNotSupported +} + +func (*fwdTestNetworkEndpoint) Close() {} + +// fwdTestNetworkProtocol is a network-layer protocol that implements Address +// resolution. +type fwdTestNetworkProtocol struct { + addrCache *linkAddrCache + addrResolveDelay time.Duration + onLinkAddressResolved func(cache *linkAddrCache, addr tcpip.Address) + onResolveStaticAddress func(tcpip.Address) (tcpip.LinkAddress, bool) +} + +func (f *fwdTestNetworkProtocol) Number() tcpip.NetworkProtocolNumber { + return fwdTestNetNumber +} + +func (f *fwdTestNetworkProtocol) MinimumPacketSize() int { + return fwdTestNetHeaderLen +} + +func (f *fwdTestNetworkProtocol) DefaultPrefixLen() int { + return fwdTestNetDefaultPrefixLen +} + +func (*fwdTestNetworkProtocol) ParseAddresses(v buffer.View) (src, dst tcpip.Address) { + return tcpip.Address(v[1:2]), tcpip.Address(v[0:1]) +} + +func (f *fwdTestNetworkProtocol) NewEndpoint(nicID tcpip.NICID, addrWithPrefix tcpip.AddressWithPrefix, linkAddrCache LinkAddressCache, dispatcher TransportDispatcher, ep LinkEndpoint, _ *Stack) (NetworkEndpoint, *tcpip.Error) { + return &fwdTestNetworkEndpoint{ + nicID: nicID, + id: NetworkEndpointID{LocalAddress: addrWithPrefix.Address}, + prefixLen: addrWithPrefix.PrefixLen, + proto: f, + dispatcher: dispatcher, + ep: ep, + }, nil +} + +func (f *fwdTestNetworkProtocol) SetOption(option interface{}) *tcpip.Error { + return tcpip.ErrUnknownProtocolOption +} + +func (f *fwdTestNetworkProtocol) Option(option interface{}) *tcpip.Error { + return tcpip.ErrUnknownProtocolOption +} + +func (f *fwdTestNetworkProtocol) Close() {} + +func (f *fwdTestNetworkProtocol) Wait() {} + +func (f *fwdTestNetworkProtocol) LinkAddressRequest(addr, localAddr tcpip.Address, linkEP LinkEndpoint) *tcpip.Error { + if f.addrCache != nil && f.onLinkAddressResolved != nil { + time.AfterFunc(f.addrResolveDelay, func() { + f.onLinkAddressResolved(f.addrCache, addr) + }) + } + return nil +} + +func (f *fwdTestNetworkProtocol) ResolveStaticAddress(addr tcpip.Address) (tcpip.LinkAddress, bool) { + if f.onResolveStaticAddress != nil { + return f.onResolveStaticAddress(addr) + } + return "", false +} + +func (f *fwdTestNetworkProtocol) LinkAddressProtocol() tcpip.NetworkProtocolNumber { + return fwdTestNetNumber +} + +// fwdTestPacketInfo holds all the information about an outbound packet. +type fwdTestPacketInfo struct { + RemoteLinkAddress tcpip.LinkAddress + LocalLinkAddress tcpip.LinkAddress + Pkt PacketBuffer +} + +type fwdTestLinkEndpoint struct { + dispatcher NetworkDispatcher + mtu uint32 + linkAddr tcpip.LinkAddress + + // C is where outbound packets are queued. + C chan fwdTestPacketInfo +} + +// InjectInbound injects an inbound packet. +func (e *fwdTestLinkEndpoint) InjectInbound(protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) { + e.InjectLinkAddr(protocol, "", pkt) +} + +// InjectLinkAddr injects an inbound packet with a remote link address. +func (e *fwdTestLinkEndpoint) InjectLinkAddr(protocol tcpip.NetworkProtocolNumber, remote tcpip.LinkAddress, pkt PacketBuffer) { + e.dispatcher.DeliverNetworkPacket(e, remote, "" /* local */, protocol, pkt) +} + +// Attach saves the stack network-layer dispatcher for use later when packets +// are injected. +func (e *fwdTestLinkEndpoint) Attach(dispatcher NetworkDispatcher) { + e.dispatcher = dispatcher +} + +// IsAttached implements stack.LinkEndpoint.IsAttached. +func (e *fwdTestLinkEndpoint) IsAttached() bool { + return e.dispatcher != nil +} + +// MTU implements stack.LinkEndpoint.MTU. It returns the value initialized +// during construction. +func (e *fwdTestLinkEndpoint) MTU() uint32 { + return e.mtu +} + +// Capabilities implements stack.LinkEndpoint.Capabilities. +func (e fwdTestLinkEndpoint) Capabilities() LinkEndpointCapabilities { + caps := LinkEndpointCapabilities(0) + return caps | CapabilityResolutionRequired +} + +// GSOMaxSize returns the maximum GSO packet size. +func (*fwdTestLinkEndpoint) GSOMaxSize() uint32 { + return 1 << 15 +} + +// MaxHeaderLength returns the maximum size of the link layer header. Given it +// doesn't have a header, it just returns 0. +func (*fwdTestLinkEndpoint) MaxHeaderLength() uint16 { + return 0 +} + +// LinkAddress returns the link address of this endpoint. +func (e *fwdTestLinkEndpoint) LinkAddress() tcpip.LinkAddress { + return e.linkAddr +} + +func (e fwdTestLinkEndpoint) WritePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) *tcpip.Error { + p := fwdTestPacketInfo{ + RemoteLinkAddress: r.RemoteLinkAddress, + LocalLinkAddress: r.LocalLinkAddress, + Pkt: pkt, + } + + select { + case e.C <- p: + default: + } + + return nil +} + +// WritePackets stores outbound packets into the channel. +func (e *fwdTestLinkEndpoint) WritePackets(r *Route, gso *GSO, pkts []PacketBuffer, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) { + n := 0 + for _, pkt := range pkts { + e.WritePacket(r, gso, protocol, pkt) + n++ + } + + return n, nil +} + +// WriteRawPacket implements stack.LinkEndpoint.WriteRawPacket. +func (e *fwdTestLinkEndpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error { + p := fwdTestPacketInfo{ + Pkt: PacketBuffer{Data: vv}, + } + + select { + case e.C <- p: + default: + } + + return nil +} + +// Wait implements stack.LinkEndpoint.Wait. +func (*fwdTestLinkEndpoint) Wait() {} + +func fwdTestNetFactory(t *testing.T, proto *fwdTestNetworkProtocol) (ep1, ep2 *fwdTestLinkEndpoint) { + // Create a stack with the network protocol and two NICs. + s := New(Options{ + NetworkProtocols: []NetworkProtocol{proto}, + }) + + proto.addrCache = s.linkAddrCache + + // Enable forwarding. + s.SetForwarding(true) + + // NIC 1 has the link address "a", and added the network address 1. + ep1 = &fwdTestLinkEndpoint{ + C: make(chan fwdTestPacketInfo, 300), + mtu: fwdTestNetDefaultMTU, + linkAddr: "a", + } + if err := s.CreateNIC(1, ep1); err != nil { + t.Fatal("CreateNIC #1 failed:", err) + } + if err := s.AddAddress(1, fwdTestNetNumber, "\x01"); err != nil { + t.Fatal("AddAddress #1 failed:", err) + } + + // NIC 2 has the link address "b", and added the network address 2. + ep2 = &fwdTestLinkEndpoint{ + C: make(chan fwdTestPacketInfo, 300), + mtu: fwdTestNetDefaultMTU, + linkAddr: "b", + } + if err := s.CreateNIC(2, ep2); err != nil { + t.Fatal("CreateNIC #2 failed:", err) + } + if err := s.AddAddress(2, fwdTestNetNumber, "\x02"); err != nil { + t.Fatal("AddAddress #2 failed:", err) + } + + // Route all packets to NIC 2. + { + subnet, err := tcpip.NewSubnet("\x00", "\x00") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{{Destination: subnet, NIC: 2}}) + } + + return ep1, ep2 +} + +func TestForwardingWithStaticResolver(t *testing.T) { + // Create a network protocol with a static resolver. + proto := &fwdTestNetworkProtocol{ + onResolveStaticAddress: + // The network address 3 is resolved to the link address "c". + func(addr tcpip.Address) (tcpip.LinkAddress, bool) { + if addr == "\x03" { + return "c", true + } + return "", false + }, + } + + ep1, ep2 := fwdTestNetFactory(t, proto) + + // Inject an inbound packet to address 3 on NIC 1, and see if it is + // forwarded to NIC 2. + buf := buffer.NewView(30) + buf[0] = 3 + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + + var p fwdTestPacketInfo + + select { + case p = <-ep2.C: + default: + t.Fatal("packet not forwarded") + } + + // Test that the static address resolution happened correctly. + if p.RemoteLinkAddress != "c" { + t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress) + } + if p.LocalLinkAddress != "b" { + t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress) + } +} + +func TestForwardingWithFakeResolver(t *testing.T) { + // Create a network protocol with a fake resolver. + proto := &fwdTestNetworkProtocol{ + addrResolveDelay: 500 * time.Millisecond, + onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) { + // Any address will be resolved to the link address "c". + cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c") + }, + } + + ep1, ep2 := fwdTestNetFactory(t, proto) + + // Inject an inbound packet to address 3 on NIC 1, and see if it is + // forwarded to NIC 2. + buf := buffer.NewView(30) + buf[0] = 3 + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + + var p fwdTestPacketInfo + + select { + case p = <-ep2.C: + case <-time.After(time.Second): + t.Fatal("packet not forwarded") + } + + // Test that the address resolution happened correctly. + if p.RemoteLinkAddress != "c" { + t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress) + } + if p.LocalLinkAddress != "b" { + t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress) + } +} + +func TestForwardingWithNoResolver(t *testing.T) { + // Create a network protocol without a resolver. + proto := &fwdTestNetworkProtocol{} + + ep1, ep2 := fwdTestNetFactory(t, proto) + + // inject an inbound packet to address 3 on NIC 1, and see if it is + // forwarded to NIC 2. + buf := buffer.NewView(30) + buf[0] = 3 + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + + select { + case <-ep2.C: + t.Fatal("Packet should not be forwarded") + case <-time.After(time.Second): + } +} + +func TestForwardingWithFakeResolverPartialTimeout(t *testing.T) { + // Create a network protocol with a fake resolver. + proto := &fwdTestNetworkProtocol{ + addrResolveDelay: 500 * time.Millisecond, + onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) { + // Only packets to address 3 will be resolved to the + // link address "c". + if addr == "\x03" { + cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c") + } + }, + } + + ep1, ep2 := fwdTestNetFactory(t, proto) + + // Inject an inbound packet to address 4 on NIC 1. This packet should + // not be forwarded. + buf := buffer.NewView(30) + buf[0] = 4 + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + + // Inject an inbound packet to address 3 on NIC 1, and see if it is + // forwarded to NIC 2. + buf = buffer.NewView(30) + buf[0] = 3 + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + + var p fwdTestPacketInfo + + select { + case p = <-ep2.C: + case <-time.After(time.Second): + t.Fatal("packet not forwarded") + } + + b := p.Pkt.Header.View() + if b[0] != 3 { + t.Fatalf("got b[0] = %d, want = 3", b[0]) + } + + // Test that the address resolution happened correctly. + if p.RemoteLinkAddress != "c" { + t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress) + } + if p.LocalLinkAddress != "b" { + t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress) + } +} + +func TestForwardingWithFakeResolverTwoPackets(t *testing.T) { + // Create a network protocol with a fake resolver. + proto := &fwdTestNetworkProtocol{ + addrResolveDelay: 500 * time.Millisecond, + onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) { + // Any packets will be resolved to the link address "c". + cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c") + }, + } + + ep1, ep2 := fwdTestNetFactory(t, proto) + + // Inject two inbound packets to address 3 on NIC 1. + for i := 0; i < 2; i++ { + buf := buffer.NewView(30) + buf[0] = 3 + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + } + + for i := 0; i < 2; i++ { + var p fwdTestPacketInfo + + select { + case p = <-ep2.C: + case <-time.After(time.Second): + t.Fatal("packet not forwarded") + } + + b := p.Pkt.Header.View() + if b[0] != 3 { + t.Fatalf("got b[0] = %d, want = 3", b[0]) + } + + // Test that the address resolution happened correctly. + if p.RemoteLinkAddress != "c" { + t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress) + } + if p.LocalLinkAddress != "b" { + t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress) + } + } +} + +func TestForwardingWithFakeResolverManyPackets(t *testing.T) { + // Create a network protocol with a fake resolver. + proto := &fwdTestNetworkProtocol{ + addrResolveDelay: 500 * time.Millisecond, + onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) { + // Any packets will be resolved to the link address "c". + cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c") + }, + } + + ep1, ep2 := fwdTestNetFactory(t, proto) + + for i := 0; i < maxPendingPacketsPerResolution+5; i++ { + // Inject inbound 'maxPendingPacketsPerResolution + 5' packets on NIC 1. + buf := buffer.NewView(30) + buf[0] = 3 + // Set the packet sequence number. + binary.BigEndian.PutUint16(buf[fwdTestNetHeaderLen:], uint16(i)) + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + } + + for i := 0; i < maxPendingPacketsPerResolution; i++ { + var p fwdTestPacketInfo + + select { + case p = <-ep2.C: + case <-time.After(time.Second): + t.Fatal("packet not forwarded") + } + + b := p.Pkt.Header.View() + if b[0] != 3 { + t.Fatalf("got b[0] = %d, want = 3", b[0]) + } + // The first 5 packets should not be forwarded so the the + // sequemnce number should start with 5. + want := uint16(i + 5) + if n := binary.BigEndian.Uint16(b[fwdTestNetHeaderLen:]); n != want { + t.Fatalf("got the packet #%d, want = #%d", n, want) + } + + // Test that the address resolution happened correctly. + if p.RemoteLinkAddress != "c" { + t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress) + } + if p.LocalLinkAddress != "b" { + t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress) + } + } +} + +func TestForwardingWithFakeResolverManyResolutions(t *testing.T) { + // Create a network protocol with a fake resolver. + proto := &fwdTestNetworkProtocol{ + addrResolveDelay: 500 * time.Millisecond, + onLinkAddressResolved: func(cache *linkAddrCache, addr tcpip.Address) { + // Any packets will be resolved to the link address "c". + cache.add(tcpip.FullAddress{NIC: 2, Addr: addr}, "c") + }, + } + + ep1, ep2 := fwdTestNetFactory(t, proto) + + for i := 0; i < maxPendingResolutions+5; i++ { + // Inject inbound 'maxPendingResolutions + 5' packets on NIC 1. + // Each packet has a different destination address (3 to + // maxPendingResolutions + 7). + buf := buffer.NewView(30) + buf[0] = byte(3 + i) + ep1.InjectInbound(fwdTestNetNumber, PacketBuffer{ + Data: buf.ToVectorisedView(), + }) + } + + for i := 0; i < maxPendingResolutions; i++ { + var p fwdTestPacketInfo + + select { + case p = <-ep2.C: + case <-time.After(time.Second): + t.Fatal("packet not forwarded") + } + + // The first 5 packets (address 3 to 7) should not be forwarded + // because their address resolutions are interrupted. + b := p.Pkt.Header.View() + if b[0] < 8 { + t.Fatalf("got b[0] = %d, want b[0] >= 8", b[0]) + } + + // Test that the address resolution happened correctly. + if p.RemoteLinkAddress != "c" { + t.Fatalf("got p.RemoteLinkAddress = %s, want = c", p.RemoteLinkAddress) + } + if p.LocalLinkAddress != "b" { + t.Fatalf("got p.LocalLinkAddress = %s, want = b", p.LocalLinkAddress) + } + } +} diff --git a/pkg/tcpip/stack/iptables.go b/pkg/tcpip/stack/iptables.go new file mode 100644 index 000000000..37907ae24 --- /dev/null +++ b/pkg/tcpip/stack/iptables.go @@ -0,0 +1,311 @@ +// 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 + +import ( + "fmt" + + "gvisor.dev/gvisor/pkg/tcpip/header" +) + +// Table names. +const ( + TablenameNat = "nat" + TablenameMangle = "mangle" + TablenameFilter = "filter" +) + +// Chain names as defined by net/ipv4/netfilter/ip_tables.c. +const ( + ChainNamePrerouting = "PREROUTING" + ChainNameInput = "INPUT" + ChainNameForward = "FORWARD" + ChainNameOutput = "OUTPUT" + ChainNamePostrouting = "POSTROUTING" +) + +// HookUnset indicates that there is no hook set for an entrypoint or +// underflow. +const HookUnset = -1 + +// DefaultTables returns a default set of tables. Each chain is set to accept +// all packets. +func DefaultTables() IPTables { + // TODO(gvisor.dev/issue/170): We may be able to swap out some strings for + // iotas. + return IPTables{ + Tables: map[string]Table{ + TablenameNat: Table{ + Rules: []Rule{ + Rule{Target: AcceptTarget{}}, + Rule{Target: AcceptTarget{}}, + Rule{Target: AcceptTarget{}}, + Rule{Target: AcceptTarget{}}, + Rule{Target: ErrorTarget{}}, + }, + BuiltinChains: map[Hook]int{ + Prerouting: 0, + Input: 1, + Output: 2, + Postrouting: 3, + }, + Underflows: map[Hook]int{ + Prerouting: 0, + Input: 1, + Output: 2, + Postrouting: 3, + }, + UserChains: map[string]int{}, + }, + TablenameMangle: Table{ + Rules: []Rule{ + Rule{Target: AcceptTarget{}}, + Rule{Target: AcceptTarget{}}, + Rule{Target: ErrorTarget{}}, + }, + BuiltinChains: map[Hook]int{ + Prerouting: 0, + Output: 1, + }, + Underflows: map[Hook]int{ + Prerouting: 0, + Output: 1, + }, + UserChains: map[string]int{}, + }, + TablenameFilter: Table{ + Rules: []Rule{ + Rule{Target: AcceptTarget{}}, + Rule{Target: AcceptTarget{}}, + Rule{Target: AcceptTarget{}}, + Rule{Target: ErrorTarget{}}, + }, + BuiltinChains: map[Hook]int{ + Input: 0, + Forward: 1, + Output: 2, + }, + Underflows: map[Hook]int{ + Input: 0, + Forward: 1, + Output: 2, + }, + UserChains: map[string]int{}, + }, + }, + Priorities: map[Hook][]string{ + Input: []string{TablenameNat, TablenameFilter}, + Prerouting: []string{TablenameMangle, TablenameNat}, + Output: []string{TablenameMangle, TablenameNat, TablenameFilter}, + }, + } +} + +// EmptyFilterTable returns a Table with no rules and the filter table chains +// mapped to HookUnset. +func EmptyFilterTable() Table { + return Table{ + Rules: []Rule{}, + BuiltinChains: map[Hook]int{ + Input: HookUnset, + Forward: HookUnset, + Output: HookUnset, + }, + Underflows: map[Hook]int{ + Input: HookUnset, + Forward: HookUnset, + Output: HookUnset, + }, + UserChains: map[string]int{}, + } +} + +// EmptyNatTable returns a Table with no rules and the filter table chains +// mapped to HookUnset. +func EmptyNatTable() Table { + return Table{ + Rules: []Rule{}, + BuiltinChains: map[Hook]int{ + Prerouting: HookUnset, + Input: HookUnset, + Output: HookUnset, + Postrouting: HookUnset, + }, + Underflows: map[Hook]int{ + Prerouting: HookUnset, + Input: HookUnset, + Output: HookUnset, + Postrouting: HookUnset, + }, + UserChains: map[string]int{}, + } +} + +// A chainVerdict is what a table decides should be done with a packet. +type chainVerdict int + +const ( + // chainAccept indicates the packet should continue through netstack. + chainAccept chainVerdict = iota + + // chainAccept indicates the packet should be dropped. + chainDrop + + // chainReturn indicates the packet should return to the calling chain + // or the underflow rule of a builtin chain. + chainReturn +) + +// Check runs pkt through the rules for hook. It returns true when the packet +// should continue traversing the network stack and false when it should be +// dropped. +// +// Precondition: pkt.NetworkHeader is set. +func (it *IPTables) Check(hook Hook, pkt PacketBuffer) bool { + // Go through each table containing the hook. + for _, tablename := range it.Priorities[hook] { + table := it.Tables[tablename] + ruleIdx := table.BuiltinChains[hook] + switch verdict := it.checkChain(hook, pkt, table, ruleIdx); verdict { + // If the table returns Accept, move on to the next table. + case chainAccept: + continue + // The Drop verdict is final. + case chainDrop: + return false + case chainReturn: + // Any Return from a built-in chain means we have to + // call the underflow. + underflow := table.Rules[table.Underflows[hook]] + switch v, _ := underflow.Target.Action(pkt); v { + case RuleAccept: + continue + case RuleDrop: + return false + case RuleJump, RuleReturn: + panic("Underflows should only return RuleAccept or RuleDrop.") + default: + panic(fmt.Sprintf("Unknown verdict: %d", v)) + } + + default: + panic(fmt.Sprintf("Unknown verdict %v.", verdict)) + } + } + + // Every table returned Accept. + return true +} + +// Precondition: pkt.NetworkHeader is set. +func (it *IPTables) checkChain(hook Hook, pkt PacketBuffer, table Table, ruleIdx int) chainVerdict { + // Start from ruleIdx and walk the list of rules until a rule gives us + // a verdict. + for ruleIdx < len(table.Rules) { + switch verdict, jumpTo := it.checkRule(hook, pkt, table, ruleIdx); verdict { + case RuleAccept: + return chainAccept + + case RuleDrop: + return chainDrop + + case RuleReturn: + return chainReturn + + case RuleJump: + // "Jumping" to the next rule just means we're + // continuing on down the list. + if jumpTo == ruleIdx+1 { + ruleIdx++ + continue + } + switch verdict := it.checkChain(hook, pkt, table, jumpTo); verdict { + case chainAccept: + return chainAccept + case chainDrop: + return chainDrop + case chainReturn: + ruleIdx++ + continue + default: + panic(fmt.Sprintf("Unknown verdict: %d", verdict)) + } + + default: + panic(fmt.Sprintf("Unknown verdict: %d", verdict)) + } + + } + + // We got through the entire table without a decision. Default to DROP + // for safety. + return chainDrop +} + +// Precondition: pk.NetworkHeader is set. +func (it *IPTables) checkRule(hook Hook, pkt PacketBuffer, table Table, ruleIdx int) (RuleVerdict, int) { + rule := table.Rules[ruleIdx] + + // If pkt.NetworkHeader hasn't been set yet, it will be contained in + // pkt.Data.First(). + if pkt.NetworkHeader == nil { + pkt.NetworkHeader = pkt.Data.First() + } + + // Check whether the packet matches the IP header filter. + if !filterMatch(rule.Filter, header.IPv4(pkt.NetworkHeader)) { + // Continue on to the next rule. + return RuleJump, ruleIdx + 1 + } + + // Go through each rule matcher. If they all match, run + // the rule target. + for _, matcher := range rule.Matchers { + matches, hotdrop := matcher.Match(hook, pkt, "") + if hotdrop { + return RuleDrop, 0 + } + if !matches { + // Continue on to the next rule. + return RuleJump, ruleIdx + 1 + } + } + + // All the matchers matched, so run the target. + return rule.Target.Action(pkt) +} + +func filterMatch(filter IPHeaderFilter, hdr header.IPv4) bool { + // TODO(gvisor.dev/issue/170): Support other fields of the filter. + // Check the transport protocol. + if filter.Protocol != 0 && filter.Protocol != hdr.TransportProtocol() { + return false + } + + // Check the destination IP. + dest := hdr.DestinationAddress() + matches := true + for i := range filter.Dst { + if dest[i]&filter.DstMask[i] != filter.Dst[i] { + matches = false + break + } + } + if matches == filter.DstInvert { + return false + } + + return true +} diff --git a/pkg/tcpip/stack/iptables_targets.go b/pkg/tcpip/stack/iptables_targets.go new file mode 100644 index 000000000..7b4543caf --- /dev/null +++ b/pkg/tcpip/stack/iptables_targets.go @@ -0,0 +1,144 @@ +// 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 + +import ( + "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/header" +) + +// AcceptTarget accepts packets. +type AcceptTarget struct{} + +// Action implements Target.Action. +func (AcceptTarget) Action(packet PacketBuffer) (RuleVerdict, int) { + return RuleAccept, 0 +} + +// DropTarget drops packets. +type DropTarget struct{} + +// Action implements Target.Action. +func (DropTarget) Action(packet PacketBuffer) (RuleVerdict, int) { + return RuleDrop, 0 +} + +// ErrorTarget logs an error and drops the packet. It represents a target that +// should be unreachable. +type ErrorTarget struct{} + +// Action implements Target.Action. +func (ErrorTarget) Action(packet PacketBuffer) (RuleVerdict, int) { + log.Debugf("ErrorTarget triggered.") + return RuleDrop, 0 +} + +// UserChainTarget marks a rule as the beginning of a user chain. +type UserChainTarget struct { + Name string +} + +// Action implements Target.Action. +func (UserChainTarget) Action(PacketBuffer) (RuleVerdict, int) { + panic("UserChainTarget should never be called.") +} + +// ReturnTarget returns from the current chain. If the chain is a built-in, the +// hook's underflow should be called. +type ReturnTarget struct{} + +// Action implements Target.Action. +func (ReturnTarget) Action(PacketBuffer) (RuleVerdict, int) { + return RuleReturn, 0 +} + +// RedirectTarget redirects the packet by modifying the destination port/IP. +// Min and Max values for IP and Ports in the struct indicate the range of +// values which can be used to redirect. +type RedirectTarget struct { + // TODO(gvisor.dev/issue/170): Other flags need to be added after + // we support them. + // RangeProtoSpecified flag indicates single port is specified to + // redirect. + RangeProtoSpecified bool + + // Min address used to redirect. + MinIP tcpip.Address + + // Max address used to redirect. + MaxIP tcpip.Address + + // Min port used to redirect. + MinPort uint16 + + // Max port used to redirect. + MaxPort uint16 +} + +// Action implements Target.Action. +// TODO(gvisor.dev/issue/170): Parse headers without copying. The current +// implementation only works for PREROUTING and calls pkt.Clone(), neither +// of which should be the case. +func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) { + newPkt := pkt.Clone() + + // Set network header. + headerView := newPkt.Data.First() + netHeader := header.IPv4(headerView) + newPkt.NetworkHeader = headerView[:header.IPv4MinimumSize] + + hlen := int(netHeader.HeaderLength()) + tlen := int(netHeader.TotalLength()) + newPkt.Data.TrimFront(hlen) + newPkt.Data.CapLength(tlen - hlen) + + // TODO(gvisor.dev/issue/170): Change destination address to + // loopback or interface address on which the packet was + // received. + + // TODO(gvisor.dev/issue/170): Check Flags in RedirectTarget if + // we need to change dest address (for OUTPUT chain) or ports. + switch protocol := netHeader.TransportProtocol(); protocol { + case header.UDPProtocolNumber: + var udpHeader header.UDP + if newPkt.TransportHeader != nil { + udpHeader = header.UDP(newPkt.TransportHeader) + } else { + if len(pkt.Data.First()) < header.UDPMinimumSize { + return RuleDrop, 0 + } + udpHeader = header.UDP(newPkt.Data.First()) + } + udpHeader.SetDestinationPort(rt.MinPort) + case header.TCPProtocolNumber: + var tcpHeader header.TCP + if newPkt.TransportHeader != nil { + tcpHeader = header.TCP(newPkt.TransportHeader) + } else { + if len(pkt.Data.First()) < header.TCPMinimumSize { + return RuleDrop, 0 + } + tcpHeader = header.TCP(newPkt.TransportHeader) + } + // TODO(gvisor.dev/issue/170): Need to recompute checksum + // and implement nat connection tracking to support TCP. + tcpHeader.SetDestinationPort(rt.MinPort) + default: + return RuleDrop, 0 + } + + return RuleAccept, 0 +} diff --git a/pkg/tcpip/stack/iptables_types.go b/pkg/tcpip/stack/iptables_types.go new file mode 100644 index 000000000..2ffb55f2a --- /dev/null +++ b/pkg/tcpip/stack/iptables_types.go @@ -0,0 +1,180 @@ +// 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 + +import ( + "gvisor.dev/gvisor/pkg/tcpip" +) + +// A Hook specifies one of the hooks built into the network stack. +// +// Userspace app Userspace app +// ^ | +// | v +// [Input] [Output] +// ^ | +// | v +// | routing +// | | +// | v +// ----->[Prerouting]----->routing----->[Forward]---------[Postrouting]-----> +type Hook uint + +// These values correspond to values in include/uapi/linux/netfilter.h. +const ( + // Prerouting happens before a packet is routed to applications or to + // be forwarded. + Prerouting Hook = iota + + // Input happens before a packet reaches an application. + Input + + // Forward happens once it's decided that a packet should be forwarded + // to another host. + Forward + + // Output happens after a packet is written by an application to be + // sent out. + Output + + // Postrouting happens just before a packet goes out on the wire. + Postrouting + + // The total number of hooks. + NumHooks +) + +// A RuleVerdict is what a rule decides should be done with a packet. +type RuleVerdict int + +const ( + // RuleAccept indicates the packet should continue through netstack. + RuleAccept RuleVerdict = iota + + // RuleDrop indicates the packet should be dropped. + RuleDrop + + // RuleJump indicates the packet should jump to another chain. + RuleJump + + // RuleReturn indicates the packet should return to the previous chain. + RuleReturn +) + +// IPTables holds all the tables for a netstack. +type IPTables struct { + // Tables maps table names to tables. User tables have arbitrary names. + Tables map[string]Table + + // Priorities maps each hook to a list of table names. The order of the + // list is the order in which each table should be visited for that + // hook. + Priorities map[Hook][]string +} + +// A Table defines a set of chains and hooks into the network stack. It is +// really just a list of rules with some metadata for entrypoints and such. +type Table struct { + // Rules holds the rules that make up the table. + Rules []Rule + + // BuiltinChains maps builtin chains to their entrypoint rule in Rules. + BuiltinChains map[Hook]int + + // Underflows maps builtin chains to their underflow rule in Rules + // (i.e. the rule to execute if the chain returns without a verdict). + Underflows map[Hook]int + + // UserChains holds user-defined chains for the keyed by name. Users + // can give their chains arbitrary names. + UserChains map[string]int + + // Metadata holds information about the Table that is useful to users + // of IPTables, but not to the netstack IPTables code itself. + metadata interface{} +} + +// ValidHooks returns a bitmap of the builtin hooks for the given table. +func (table *Table) ValidHooks() uint32 { + hooks := uint32(0) + for hook := range table.BuiltinChains { + hooks |= 1 << hook + } + return hooks +} + +// Metadata returns the metadata object stored in table. +func (table *Table) Metadata() interface{} { + return table.metadata +} + +// SetMetadata sets the metadata object stored in table. +func (table *Table) SetMetadata(metadata interface{}) { + table.metadata = metadata +} + +// A Rule is a packet processing rule. It consists of two pieces. First it +// contains zero or more matchers, each of which is a specification of which +// packets this rule applies to. If there are no matchers in the rule, it +// applies to any packet. +type Rule struct { + // Filter holds basic IP filtering fields common to every rule. + Filter IPHeaderFilter + + // Matchers is the list of matchers for this rule. + Matchers []Matcher + + // Target is the action to invoke if all the matchers match the packet. + Target Target +} + +// IPHeaderFilter holds basic IP filtering data common to every rule. +type IPHeaderFilter struct { + // Protocol matches the transport protocol. + Protocol tcpip.TransportProtocolNumber + + // Dst matches the destination IP address. + Dst tcpip.Address + + // DstMask masks bits of the destination IP address when comparing with + // Dst. + DstMask tcpip.Address + + // DstInvert inverts the meaning of the destination IP check, i.e. when + // true the filter will match packets that fail the destination + // comparison. + DstInvert bool +} + +// A Matcher is the interface for matching packets. +type Matcher interface { + // Name returns the name of the Matcher. + Name() string + + // Match returns whether the packet matches and whether the packet + // should be "hotdropped", i.e. dropped immediately. This is usually + // used for suspicious packets. + // + // Precondition: packet.NetworkHeader is set. + Match(hook Hook, packet PacketBuffer, interfaceName string) (matches bool, hotdrop bool) +} + +// A Target is the interface for taking an action for a packet. +type Target interface { + // Action takes an action on the packet and returns a verdict on how + // traversal should (or should not) continue. If the return value is + // Jump, it also returns the index of the rule to jump to. + Action(packet PacketBuffer) (RuleVerdict, int) +} diff --git a/pkg/tcpip/stack/ndp.go b/pkg/tcpip/stack/ndp.go index f651871ce..630fdefc5 100644 --- a/pkg/tcpip/stack/ndp.go +++ b/pkg/tcpip/stack/ndp.go @@ -361,16 +361,16 @@ type ndpState struct { // The default routers discovered through Router Advertisements. defaultRouters map[tcpip.Address]defaultRouterState + // The timer used to send the next router solicitation message. + rtrSolicitTimer *time.Timer + // The on-link prefixes discovered through Router Advertisements' Prefix // Information option. onLinkPrefixes map[tcpip.Subnet]onLinkPrefixState - // The timer used to send the next router solicitation message. - // If routers are being solicited, rtrSolicitTimer MUST NOT be nil. - rtrSolicitTimer *time.Timer - - // The addresses generated by SLAAC. - autoGenAddresses map[tcpip.Address]autoGenAddressState + // The SLAAC prefixes discovered through Router Advertisements' Prefix + // Information option. + slaacPrefixes map[tcpip.Subnet]slaacPrefixState // The last learned DHCPv6 configuration from an NDP RA. dhcpv6Configuration DHCPv6ConfigurationFromNDPRA @@ -402,18 +402,16 @@ type onLinkPrefixState struct { invalidationTimer tcpip.CancellableTimer } -// autoGenAddressState holds data associated with an address generated via -// SLAAC. -type autoGenAddressState struct { - // A reference to the referencedNetworkEndpoint that this autoGenAddressState - // is holding state for. - ref *referencedNetworkEndpoint - +// slaacPrefixState holds state associated with a SLAAC prefix. +type slaacPrefixState struct { deprecationTimer tcpip.CancellableTimer invalidationTimer tcpip.CancellableTimer // Nonzero only when the address is not valid forever. validUntil time.Time + + // The prefix's permanent address endpoint. + ref *referencedNetworkEndpoint } // startDuplicateAddressDetection performs Duplicate Address Detection. @@ -566,7 +564,7 @@ func (ndp *ndpState) sendDADPacket(addr tcpip.Address) *tcpip.Error { Protocol: header.ICMPv6ProtocolNumber, TTL: header.NDPHopLimit, TOS: DefaultTOS, - }, tcpip.PacketBuffer{Header: hdr}, + }, PacketBuffer{Header: hdr}, ); err != nil { sent.Dropped.Increment() return err @@ -899,23 +897,15 @@ func (ndp *ndpState) handleAutonomousPrefixInformation(pi header.NDPPrefixInform prefix := pi.Subnet() - // Check if we already have an auto-generated address for prefix. - for addr, addrState := range ndp.autoGenAddresses { - refAddrWithPrefix := tcpip.AddressWithPrefix{Address: addr, PrefixLen: addrState.ref.ep.PrefixLen()} - if refAddrWithPrefix.Subnet() != prefix { - continue - } - - // At this point, we know we are refreshing a SLAAC generated IPv6 address - // with the prefix prefix. Do the work as outlined by RFC 4862 section - // 5.5.3.e. - ndp.refreshAutoGenAddressLifetimes(addr, pl, vl) + // Check if we already maintain SLAAC state for prefix. + if _, ok := ndp.slaacPrefixes[prefix]; ok { + // As per RFC 4862 section 5.5.3.e, refresh prefix's SLAAC lifetimes. + ndp.refreshSLAACPrefixLifetimes(prefix, pl, vl) return } - // We do not already have an address with the prefix prefix. Do the - // work as outlined by RFC 4862 section 5.5.3.d if n is configured - // to auto-generate global addresses by SLAAC. + // prefix is a new SLAAC prefix. Do the work as outlined by RFC 4862 section + // 5.5.3.d if ndp is configured to auto-generate new addresses via SLAAC. if !ndp.configs.AutoGenGlobalAddresses { return } @@ -927,6 +917,8 @@ func (ndp *ndpState) handleAutonomousPrefixInformation(pi header.NDPPrefixInform // for prefix. // // pl is the new preferred lifetime. vl is the new valid lifetime. +// +// The NIC that ndp belongs to MUST be locked. func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { // If we do not already have an address for this prefix and the valid // lifetime is 0, no need to do anything further, as per RFC 4862 @@ -942,9 +934,59 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { return } + // If the preferred lifetime is zero, then the prefix should be considered + // deprecated. + deprecated := pl == 0 + ref := ndp.addSLAACAddr(prefix, deprecated) + if ref == nil { + // We were unable to generate a permanent address for prefix so do nothing + // further as there is no reason to maintain state for a SLAAC prefix we + // cannot generate a permanent address for. + return + } + + state := slaacPrefixState{ + deprecationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() { + prefixState, ok := ndp.slaacPrefixes[prefix] + if !ok { + log.Fatalf("ndp: must have a slaacPrefixes entry for the SLAAC prefix %s", prefix) + } + + ndp.deprecateSLAACAddress(prefixState.ref) + }), + invalidationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() { + ndp.invalidateSLAACPrefix(prefix, true) + }), + ref: ref, + } + + // Setup the initial timers to deprecate and invalidate prefix. + + if !deprecated && pl < header.NDPInfiniteLifetime { + state.deprecationTimer.Reset(pl) + } + + if vl < header.NDPInfiniteLifetime { + state.invalidationTimer.Reset(vl) + state.validUntil = time.Now().Add(vl) + } + + ndp.slaacPrefixes[prefix] = state +} + +// addSLAACAddr adds a SLAAC address for prefix. +// +// The NIC that ndp belongs to MUST be locked. +func (ndp *ndpState) addSLAACAddr(prefix tcpip.Subnet, deprecated bool) *referencedNetworkEndpoint { addrBytes := []byte(prefix.ID()) if oIID := ndp.nic.stack.opaqueIIDOpts; oIID.NICNameFromID != nil { - addrBytes = header.AppendOpaqueInterfaceIdentifier(addrBytes[:header.IIDOffsetInIPv6Address], prefix, oIID.NICNameFromID(ndp.nic.ID(), ndp.nic.name), 0 /* dadCounter */, oIID.SecretKey) + addrBytes = header.AppendOpaqueInterfaceIdentifier( + addrBytes[:header.IIDOffsetInIPv6Address], + prefix, + oIID.NICNameFromID(ndp.nic.ID(), ndp.nic.name), + 0, /* dadCounter */ + oIID.SecretKey, + ) } else { // Only attempt to generate an interface-specific IID if we have a valid // link address. @@ -953,137 +995,103 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { // LinkEndpoint.LinkAddress) before reaching this point. linkAddr := ndp.nic.linkEP.LinkAddress() if !header.IsValidUnicastEthernetAddress(linkAddr) { - return + return nil } // Generate an address within prefix from the modified EUI-64 of ndp's NIC's // Ethernet MAC address. header.EthernetAdddressToModifiedEUI64IntoBuf(linkAddr, addrBytes[header.IIDOffsetInIPv6Address:]) } - addr := tcpip.Address(addrBytes) - addrWithPrefix := tcpip.AddressWithPrefix{ - Address: addr, - PrefixLen: validPrefixLenForAutoGen, + + generatedAddr := tcpip.ProtocolAddress{ + Protocol: header.IPv6ProtocolNumber, + AddressWithPrefix: tcpip.AddressWithPrefix{ + Address: tcpip.Address(addrBytes), + PrefixLen: validPrefixLenForAutoGen, + }, } // If the nic already has this address, do nothing further. - if ndp.nic.hasPermanentAddrLocked(addr) { - return + if ndp.nic.hasPermanentAddrLocked(generatedAddr.AddressWithPrefix.Address) { + return nil } // Inform the integrator that we have a new SLAAC address. ndpDisp := ndp.nic.stack.ndpDisp if ndpDisp == nil { - return + return nil } - if !ndpDisp.OnAutoGenAddress(ndp.nic.ID(), addrWithPrefix) { + + if !ndpDisp.OnAutoGenAddress(ndp.nic.ID(), generatedAddr.AddressWithPrefix) { // Informed by the integrator not to add the address. - return + return nil } - protocolAddr := tcpip.ProtocolAddress{ - Protocol: header.IPv6ProtocolNumber, - AddressWithPrefix: addrWithPrefix, - } - // If the preferred lifetime is zero, then the address should be considered - // deprecated. - deprecated := pl == 0 - ref, err := ndp.nic.addAddressLocked(protocolAddr, FirstPrimaryEndpoint, permanent, slaac, deprecated) + ref, err := ndp.nic.addAddressLocked(generatedAddr, FirstPrimaryEndpoint, permanent, slaac, deprecated) if err != nil { - log.Fatalf("ndp: error when adding address %s: %s", protocolAddr, err) - } - - state := autoGenAddressState{ - ref: ref, - deprecationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() { - addrState, ok := ndp.autoGenAddresses[addr] - if !ok { - log.Fatalf("ndp: must have an autoGenAddressess entry for the SLAAC generated IPv6 address %s", addr) - } - addrState.ref.deprecated = true - ndp.notifyAutoGenAddressDeprecated(addr) - }), - invalidationTimer: tcpip.MakeCancellableTimer(&ndp.nic.mu, func() { - ndp.invalidateAutoGenAddress(addr) - }), - } - - // Setup the initial timers to deprecate and invalidate this newly generated - // address. - - if !deprecated && pl < header.NDPInfiniteLifetime { - state.deprecationTimer.Reset(pl) + log.Fatalf("ndp: error when adding address %+v: %s", generatedAddr, err) } - if vl < header.NDPInfiniteLifetime { - state.invalidationTimer.Reset(vl) - state.validUntil = time.Now().Add(vl) - } - - ndp.autoGenAddresses[addr] = state + return ref } -// refreshAutoGenAddressLifetimes refreshes the lifetime of a SLAAC generated -// address addr. +// refreshSLAACPrefixLifetimes refreshes the lifetimes of a SLAAC prefix. // // pl is the new preferred lifetime. vl is the new valid lifetime. -func (ndp *ndpState) refreshAutoGenAddressLifetimes(addr tcpip.Address, pl, vl time.Duration) { - addrState, ok := ndp.autoGenAddresses[addr] +// +// The NIC that ndp belongs to MUST be locked. +func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, pl, vl time.Duration) { + prefixState, ok := ndp.slaacPrefixes[prefix] if !ok { - log.Fatalf("ndp: SLAAC state not found to refresh lifetimes for %s", addr) + log.Fatalf("ndp: SLAAC prefix state not found to refresh lifetimes for %s", prefix) } - defer func() { ndp.autoGenAddresses[addr] = addrState }() + defer func() { ndp.slaacPrefixes[prefix] = prefixState }() - // If the preferred lifetime is zero, then the address should be considered - // deprecated. + // If the preferred lifetime is zero, then the prefix should be deprecated. deprecated := pl == 0 - wasDeprecated := addrState.ref.deprecated - addrState.ref.deprecated = deprecated - - // Only send the deprecation event if the deprecated status for addr just - // changed from non-deprecated to deprecated. - if !wasDeprecated && deprecated { - ndp.notifyAutoGenAddressDeprecated(addr) + if deprecated { + ndp.deprecateSLAACAddress(prefixState.ref) + } else { + prefixState.ref.deprecated = false } - // If addr was preferred for some finite lifetime before, stop the deprecation - // timer so it can be reset. - addrState.deprecationTimer.StopLocked() + // If prefix was preferred for some finite lifetime before, stop the + // deprecation timer so it can be reset. + prefixState.deprecationTimer.StopLocked() - // Reset the deprecation timer if addr has a finite preferred lifetime. + // Reset the deprecation timer if prefix has a finite preferred lifetime. if !deprecated && pl < header.NDPInfiniteLifetime { - addrState.deprecationTimer.Reset(pl) + prefixState.deprecationTimer.Reset(pl) } - // As per RFC 4862 section 5.5.3.e, the valid lifetime of the address - // + // As per RFC 4862 section 5.5.3.e, update the valid lifetime for prefix: // // 1) If the received Valid Lifetime is greater than 2 hours or greater than - // RemainingLifetime, set the valid lifetime of the address to the + // RemainingLifetime, set the valid lifetime of the prefix to the // advertised Valid Lifetime. // // 2) If RemainingLifetime is less than or equal to 2 hours, ignore the // advertised Valid Lifetime. // - // 3) Otherwise, reset the valid lifetime of the address to 2 hours. + // 3) Otherwise, reset the valid lifetime of the prefix to 2 hours. // Handle the infinite valid lifetime separately as we do not keep a timer in // this case. if vl >= header.NDPInfiniteLifetime { - addrState.invalidationTimer.StopLocked() - addrState.validUntil = time.Time{} + prefixState.invalidationTimer.StopLocked() + prefixState.validUntil = time.Time{} return } var effectiveVl time.Duration var rl time.Duration - // If the address was originally set to be valid forever, assume the remaining + // If the prefix was originally set to be valid forever, assume the remaining // time to be the maximum possible value. - if addrState.validUntil == (time.Time{}) { + if prefixState.validUntil == (time.Time{}) { rl = header.NDPInfiniteLifetime } else { - rl = time.Until(addrState.validUntil) + rl = time.Until(prefixState.validUntil) } if vl > MinPrefixInformationValidLifetimeForUpdate || vl > rl { @@ -1094,58 +1102,66 @@ func (ndp *ndpState) refreshAutoGenAddressLifetimes(addr tcpip.Address, pl, vl t effectiveVl = MinPrefixInformationValidLifetimeForUpdate } - addrState.invalidationTimer.StopLocked() - addrState.invalidationTimer.Reset(effectiveVl) - addrState.validUntil = time.Now().Add(effectiveVl) -} - -// notifyAutoGenAddressDeprecated notifies the stack's NDP dispatcher that addr -// has been deprecated. -func (ndp *ndpState) notifyAutoGenAddressDeprecated(addr tcpip.Address) { - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnAutoGenAddressDeprecated(ndp.nic.ID(), tcpip.AddressWithPrefix{ - Address: addr, - PrefixLen: validPrefixLenForAutoGen, - }) - } + prefixState.invalidationTimer.StopLocked() + prefixState.invalidationTimer.Reset(effectiveVl) + prefixState.validUntil = time.Now().Add(effectiveVl) } -// invalidateAutoGenAddress invalidates an auto-generated address. +// deprecateSLAACAddress marks ref as deprecated and notifies the stack's NDP +// dispatcher that ref has been deprecated. +// +// deprecateSLAACAddress does nothing if ref is already deprecated. // // The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) invalidateAutoGenAddress(addr tcpip.Address) { - if !ndp.cleanupAutoGenAddrResourcesAndNotify(addr) { +func (ndp *ndpState) deprecateSLAACAddress(ref *referencedNetworkEndpoint) { + if ref.deprecated { return } - ndp.nic.removePermanentAddressLocked(addr) + ref.deprecated = true + if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { + ndpDisp.OnAutoGenAddressDeprecated(ndp.nic.ID(), tcpip.AddressWithPrefix{ + Address: ref.ep.ID().LocalAddress, + PrefixLen: ref.ep.PrefixLen(), + }) + } } -// cleanupAutoGenAddrResourcesAndNotify cleans up an invalidated auto-generated -// address's resources from ndp. If the stack has an NDP dispatcher, it will -// be notified that addr has been invalidated. -// -// Returns true if ndp had resources for addr to cleanup. +// invalidateSLAACPrefix invalidates a SLAAC prefix. // // The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) cleanupAutoGenAddrResourcesAndNotify(addr tcpip.Address) bool { - state, ok := ndp.autoGenAddresses[addr] +func (ndp *ndpState) invalidateSLAACPrefix(prefix tcpip.Subnet, removeAddr bool) { + state, ok := ndp.slaacPrefixes[prefix] if !ok { - return false + return } state.deprecationTimer.StopLocked() state.invalidationTimer.StopLocked() - delete(ndp.autoGenAddresses, addr) + delete(ndp.slaacPrefixes, prefix) + + addr := state.ref.ep.ID().LocalAddress + + if removeAddr { + if err := ndp.nic.removePermanentAddressLocked(addr); err != nil { + log.Fatalf("ndp: removePermanentAddressLocked(%s): %s", addr, err) + } + } if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { ndpDisp.OnAutoGenAddressInvalidated(ndp.nic.ID(), tcpip.AddressWithPrefix{ Address: addr, - PrefixLen: validPrefixLenForAutoGen, + PrefixLen: state.ref.ep.PrefixLen(), }) } +} - return true +// cleanupSLAACAddrResourcesAndNotify cleans up an invalidated SLAAC +// address's resources from ndp. +// +// The NIC that ndp belongs to MUST be locked. +func (ndp *ndpState) cleanupSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPrefix) { + ndp.invalidateSLAACPrefix(addr.Subnet(), false) } // cleanupState cleans up ndp's state. @@ -1163,21 +1179,21 @@ func (ndp *ndpState) cleanupAutoGenAddrResourcesAndNotify(addr tcpip.Address) bo // The NIC that ndp belongs to MUST be locked. func (ndp *ndpState) cleanupState(hostOnly bool) { linkLocalSubnet := header.IPv6LinkLocalPrefix.Subnet() - linkLocalAddrs := 0 - for addr := range ndp.autoGenAddresses { + linkLocalPrefixes := 0 + for prefix := range ndp.slaacPrefixes { // RFC 4862 section 5 states that routers are also expected to generate a // link-local address so we do not invalidate them if we are cleaning up // host-only state. - if hostOnly && linkLocalSubnet.Contains(addr) { - linkLocalAddrs++ + if hostOnly && prefix == linkLocalSubnet { + linkLocalPrefixes++ continue } - ndp.invalidateAutoGenAddress(addr) + ndp.invalidateSLAACPrefix(prefix, true) } - if got := len(ndp.autoGenAddresses); got != linkLocalAddrs { - log.Fatalf("ndp: still have non-linklocal auto-generated addresses after cleaning up; found = %d prefixes, of which %d are link-local", got, linkLocalAddrs) + if got := len(ndp.slaacPrefixes); got != linkLocalPrefixes { + log.Fatalf("ndp: still have non-linklocal SLAAC prefixes after cleaning up; found = %d prefixes, of which %d are link-local", got, linkLocalPrefixes) } for prefix := range ndp.onLinkPrefixes { @@ -1220,9 +1236,15 @@ func (ndp *ndpState) startSolicitingRouters() { } ndp.rtrSolicitTimer = time.AfterFunc(delay, func() { - // Send an RS message with the unspecified source address. - ref := ndp.nic.getRefOrCreateTemp(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint, forceSpoofing) - r := makeRoute(header.IPv6ProtocolNumber, header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.linkEP.LinkAddress(), ref, false, false) + // As per RFC 4861 section 4.1, the source of the RS is an address assigned + // to the sending interface, or the unspecified address if no address is + // assigned to the sending interface. + ref := ndp.nic.primaryIPv6Endpoint(header.IPv6AllRoutersMulticastAddress) + if ref == nil { + ref = ndp.nic.getRefOrCreateTemp(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint, forceSpoofing) + } + localAddr := ref.ep.ID().LocalAddress + r := makeRoute(header.IPv6ProtocolNumber, localAddr, header.IPv6AllRoutersMulticastAddress, ndp.nic.linkEP.LinkAddress(), ref, false, false) defer r.Release() // Route should resolve immediately since @@ -1234,10 +1256,25 @@ func (ndp *ndpState) startSolicitingRouters() { log.Fatalf("ndp: route resolution not immediate for route to send NDP RS (%s -> %s on NIC(%d))", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.ID()) } - payloadSize := header.ICMPv6HeaderSize + header.NDPRSMinimumSize + // As per RFC 4861 section 4.1, an NDP RS SHOULD include the source + // link-layer address option if the source address of the NDP RS is + // specified. This option MUST NOT be included if the source address is + // unspecified. + // + // TODO(b/141011931): Validate a LinkEndpoint's link address (provided by + // LinkEndpoint.LinkAddress) before reaching this point. + var optsSerializer header.NDPOptionsSerializer + if localAddr != header.IPv6Any && header.IsValidUnicastEthernetAddress(r.LocalLinkAddress) { + optsSerializer = header.NDPOptionsSerializer{ + header.NDPSourceLinkLayerAddressOption(r.LocalLinkAddress), + } + } + payloadSize := header.ICMPv6HeaderSize + header.NDPRSMinimumSize + int(optsSerializer.Length()) hdr := buffer.NewPrependable(int(r.MaxHeaderLength()) + payloadSize) pkt := header.ICMPv6(hdr.Prepend(payloadSize)) pkt.SetType(header.ICMPv6RouterSolicit) + rs := header.NDPRouterSolicit(pkt.NDPPayload()) + rs.Options().Serialize(optsSerializer) pkt.SetChecksum(header.ICMPv6Checksum(pkt, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{})) sent := r.Stats().ICMP.V6PacketsSent @@ -1246,7 +1283,7 @@ func (ndp *ndpState) startSolicitingRouters() { Protocol: header.ICMPv6ProtocolNumber, TTL: header.NDPHopLimit, TOS: DefaultTOS, - }, tcpip.PacketBuffer{Header: hdr}, + }, PacketBuffer{Header: hdr}, ); err != nil { sent.Dropped.Increment() log.Printf("startSolicitingRouters: error writing NDP router solicit message on NIC(%d); err = %s", ndp.nic.ID(), err) diff --git a/pkg/tcpip/stack/ndp_test.go b/pkg/tcpip/stack/ndp_test.go index 6e9306d09..06edd05b6 100644 --- a/pkg/tcpip/stack/ndp_test.go +++ b/pkg/tcpip/stack/ndp_test.go @@ -602,7 +602,7 @@ func TestDADFail(t *testing.T) { // Receive a packet to simulate multiple nodes owning or // attempting to own the same address. hdr := test.makeBuf(addr1) - e.InjectInbound(header.IPv6ProtocolNumber, tcpip.PacketBuffer{ + e.InjectInbound(header.IPv6ProtocolNumber, stack.PacketBuffer{ Data: hdr.View().ToVectorisedView(), }) @@ -639,8 +639,9 @@ func TestDADStop(t *testing.T) { const nicID = 1 tests := []struct { - name string - stopFn func(t *testing.T, s *stack.Stack) + name string + stopFn func(t *testing.T, s *stack.Stack) + skipFinalAddrCheck bool }{ // Tests to make sure that DAD stops when an address is removed. { @@ -661,6 +662,19 @@ func TestDADStop(t *testing.T) { } }, }, + + // Tests to make sure that DAD stops when the NIC is removed. + { + name: "Remove NIC", + stopFn: func(t *testing.T, s *stack.Stack) { + if err := s.RemoveNIC(nicID); err != nil { + t.Fatalf("RemoveNIC(%d): %s", nicID, err) + } + }, + // The NIC is removed so we can't check its addresses after calling + // stopFn. + skipFinalAddrCheck: true, + }, } for _, test := range tests { @@ -710,12 +724,15 @@ func TestDADStop(t *testing.T) { t.Errorf("dad event mismatch (-want +got):\n%s", diff) } } - addr, err = s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) - if err != nil { - t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (_, %v), want = (_, nil)", nicID, header.IPv6ProtocolNumber, err) - } - if want := (tcpip.AddressWithPrefix{}); addr != want { - t.Errorf("got stack.GetMainNICAddress(%d, %d) = (%s, nil), want = (%s, nil)", nicID, header.IPv6ProtocolNumber, addr, want) + + if !test.skipFinalAddrCheck { + addr, err := s.GetMainNICAddress(nicID, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(%d, %d) = (_, %v), want = (_, nil)", nicID, header.IPv6ProtocolNumber, err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Errorf("got stack.GetMainNICAddress(%d, %d) = (%s, nil), want = (%s, nil)", nicID, header.IPv6ProtocolNumber, addr, want) + } } // Should not have sent more than 1 NS message. @@ -901,7 +918,7 @@ func TestSetNDPConfigurations(t *testing.T) { // raBufWithOptsAndDHCPv6 returns a valid NDP Router Advertisement with options // and DHCPv6 configurations specified. -func raBufWithOptsAndDHCPv6(ip tcpip.Address, rl uint16, managedAddress, otherConfigurations bool, optSer header.NDPOptionsSerializer) tcpip.PacketBuffer { +func raBufWithOptsAndDHCPv6(ip tcpip.Address, rl uint16, managedAddress, otherConfigurations bool, optSer header.NDPOptionsSerializer) stack.PacketBuffer { icmpSize := header.ICMPv6HeaderSize + header.NDPRAMinimumSize + int(optSer.Length()) hdr := buffer.NewPrependable(header.IPv6MinimumSize + icmpSize) pkt := header.ICMPv6(hdr.Prepend(icmpSize)) @@ -936,14 +953,14 @@ func raBufWithOptsAndDHCPv6(ip tcpip.Address, rl uint16, managedAddress, otherCo DstAddr: header.IPv6AllNodesMulticastAddress, }) - return tcpip.PacketBuffer{Data: hdr.View().ToVectorisedView()} + return stack.PacketBuffer{Data: hdr.View().ToVectorisedView()} } // raBufWithOpts returns a valid NDP Router Advertisement with options. // // Note, raBufWithOpts does not populate any of the RA fields other than the // Router Lifetime. -func raBufWithOpts(ip tcpip.Address, rl uint16, optSer header.NDPOptionsSerializer) tcpip.PacketBuffer { +func raBufWithOpts(ip tcpip.Address, rl uint16, optSer header.NDPOptionsSerializer) stack.PacketBuffer { return raBufWithOptsAndDHCPv6(ip, rl, false, false, optSer) } @@ -952,7 +969,7 @@ func raBufWithOpts(ip tcpip.Address, rl uint16, optSer header.NDPOptionsSerializ // // Note, raBufWithDHCPv6 does not populate any of the RA fields other than the // DHCPv6 related ones. -func raBufWithDHCPv6(ip tcpip.Address, managedAddresses, otherConfiguratiosns bool) tcpip.PacketBuffer { +func raBufWithDHCPv6(ip tcpip.Address, managedAddresses, otherConfiguratiosns bool) stack.PacketBuffer { return raBufWithOptsAndDHCPv6(ip, 0, managedAddresses, otherConfiguratiosns, header.NDPOptionsSerializer{}) } @@ -960,7 +977,7 @@ func raBufWithDHCPv6(ip tcpip.Address, managedAddresses, otherConfiguratiosns bo // // Note, raBuf does not populate any of the RA fields other than the // Router Lifetime. -func raBuf(ip tcpip.Address, rl uint16) tcpip.PacketBuffer { +func raBuf(ip tcpip.Address, rl uint16) stack.PacketBuffer { return raBufWithOpts(ip, rl, header.NDPOptionsSerializer{}) } @@ -969,7 +986,7 @@ func raBuf(ip tcpip.Address, rl uint16) tcpip.PacketBuffer { // // Note, raBufWithPI does not populate any of the RA fields other than the // Router Lifetime. -func raBufWithPI(ip tcpip.Address, rl uint16, prefix tcpip.AddressWithPrefix, onLink, auto bool, vl, pl uint32) tcpip.PacketBuffer { +func raBufWithPI(ip tcpip.Address, rl uint16, prefix tcpip.AddressWithPrefix, onLink, auto bool, vl, pl uint32) stack.PacketBuffer { flags := uint8(0) if onLink { // The OnLink flag is the 7th bit in the flags byte. @@ -2983,11 +3000,12 @@ func TestCleanupNDPState(t *testing.T) { cleanupFn func(t *testing.T, s *stack.Stack) keepAutoGenLinkLocal bool maxAutoGenAddrEvents int + skipFinalAddrCheck bool }{ // A NIC should still keep its auto-generated link-local address when // becoming a router. { - name: "Forwarding Enable", + name: "Enable forwarding", cleanupFn: func(t *testing.T, s *stack.Stack) { t.Helper() s.SetForwarding(true) @@ -2998,7 +3016,7 @@ func TestCleanupNDPState(t *testing.T) { // A NIC should cleanup all NDP state when it is disabled. { - name: "NIC Disable", + name: "Disable NIC", cleanupFn: func(t *testing.T, s *stack.Stack) { t.Helper() @@ -3012,6 +3030,26 @@ func TestCleanupNDPState(t *testing.T) { keepAutoGenLinkLocal: false, maxAutoGenAddrEvents: 6, }, + + // A NIC should cleanup all NDP state when it is removed. + { + name: "Remove NIC", + cleanupFn: func(t *testing.T, s *stack.Stack) { + t.Helper() + + if err := s.RemoveNIC(nicID1); err != nil { + t.Fatalf("s.RemoveNIC(%d): %s", nicID1, err) + } + if err := s.RemoveNIC(nicID2); err != nil { + t.Fatalf("s.RemoveNIC(%d): %s", nicID2, err) + } + }, + keepAutoGenLinkLocal: false, + maxAutoGenAddrEvents: 6, + // The NICs are removed so we can't check their addresses after calling + // stopFn. + skipFinalAddrCheck: true, + }, } for _, test := range tests { @@ -3230,35 +3268,37 @@ func TestCleanupNDPState(t *testing.T) { t.Errorf("auto-generated address events mismatch (-want +got):\n%s", diff) } - // Make sure the auto-generated addresses got removed. - nicinfo = s.NICInfo() - nic1Addrs = nicinfo[nicID1].ProtocolAddresses - nic2Addrs = nicinfo[nicID2].ProtocolAddresses - if containsV6Addr(nic1Addrs, llAddrWithPrefix1) != test.keepAutoGenLinkLocal { - if test.keepAutoGenLinkLocal { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) - } else { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) + if !test.skipFinalAddrCheck { + // Make sure the auto-generated addresses got removed. + nicinfo = s.NICInfo() + nic1Addrs = nicinfo[nicID1].ProtocolAddresses + nic2Addrs = nicinfo[nicID2].ProtocolAddresses + if containsV6Addr(nic1Addrs, llAddrWithPrefix1) != test.keepAutoGenLinkLocal { + if test.keepAutoGenLinkLocal { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) + } else { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", llAddrWithPrefix1, nicID1, nic1Addrs) + } } - } - if containsV6Addr(nic1Addrs, e1Addr1) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr1, nicID1, nic1Addrs) - } - if containsV6Addr(nic1Addrs, e1Addr2) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr2, nicID1, nic1Addrs) - } - if containsV6Addr(nic2Addrs, llAddrWithPrefix2) != test.keepAutoGenLinkLocal { - if test.keepAutoGenLinkLocal { - t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) - } else { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) + if containsV6Addr(nic1Addrs, e1Addr1) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr1, nicID1, nic1Addrs) + } + if containsV6Addr(nic1Addrs, e1Addr2) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e1Addr2, nicID1, nic1Addrs) + } + if containsV6Addr(nic2Addrs, llAddrWithPrefix2) != test.keepAutoGenLinkLocal { + if test.keepAutoGenLinkLocal { + t.Errorf("missing %s from the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) + } else { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", llAddrWithPrefix2, nicID2, nic2Addrs) + } + } + if containsV6Addr(nic2Addrs, e2Addr1) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr1, nicID2, nic2Addrs) + } + if containsV6Addr(nic2Addrs, e2Addr2) { + t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr2, nicID2, nic2Addrs) } - } - if containsV6Addr(nic2Addrs, e2Addr1) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr1, nicID2, nic2Addrs) - } - if containsV6Addr(nic2Addrs, e2Addr2) { - t.Errorf("still have %s in the list of addresses for NIC(%d): %+v", e2Addr2, nicID2, nic2Addrs) } // Should not get any more events (invalidation timers should have been @@ -3384,6 +3424,10 @@ func TestRouterSolicitation(t *testing.T) { tests := []struct { name string linkHeaderLen uint16 + linkAddr tcpip.LinkAddress + nicAddr tcpip.Address + expectedSrcAddr tcpip.Address + expectedNDPOpts []header.NDPOption maxRtrSolicit uint8 rtrSolicitInt time.Duration effectiveRtrSolicitInt time.Duration @@ -3392,6 +3436,7 @@ func TestRouterSolicitation(t *testing.T) { }{ { name: "Single RS with delay", + expectedSrcAddr: header.IPv6Any, maxRtrSolicit: 1, rtrSolicitInt: time.Second, effectiveRtrSolicitInt: time.Second, @@ -3401,6 +3446,8 @@ func TestRouterSolicitation(t *testing.T) { { name: "Two RS with delay", linkHeaderLen: 1, + nicAddr: llAddr1, + expectedSrcAddr: llAddr1, maxRtrSolicit: 2, rtrSolicitInt: time.Second, effectiveRtrSolicitInt: time.Second, @@ -3408,8 +3455,14 @@ func TestRouterSolicitation(t *testing.T) { effectiveMaxRtrSolicitDelay: 500 * time.Millisecond, }, { - name: "Single RS without delay", - linkHeaderLen: 2, + name: "Single RS without delay", + linkHeaderLen: 2, + linkAddr: linkAddr1, + nicAddr: llAddr1, + expectedSrcAddr: llAddr1, + expectedNDPOpts: []header.NDPOption{ + header.NDPSourceLinkLayerAddressOption(linkAddr1), + }, maxRtrSolicit: 1, rtrSolicitInt: time.Second, effectiveRtrSolicitInt: time.Second, @@ -3419,6 +3472,8 @@ func TestRouterSolicitation(t *testing.T) { { name: "Two RS without delay and invalid zero interval", linkHeaderLen: 3, + linkAddr: linkAddr1, + expectedSrcAddr: header.IPv6Any, maxRtrSolicit: 2, rtrSolicitInt: 0, effectiveRtrSolicitInt: 4 * time.Second, @@ -3427,6 +3482,8 @@ func TestRouterSolicitation(t *testing.T) { }, { name: "Three RS without delay", + linkAddr: linkAddr1, + expectedSrcAddr: header.IPv6Any, maxRtrSolicit: 3, rtrSolicitInt: 500 * time.Millisecond, effectiveRtrSolicitInt: 500 * time.Millisecond, @@ -3435,6 +3492,8 @@ func TestRouterSolicitation(t *testing.T) { }, { name: "Two RS with invalid negative delay", + linkAddr: linkAddr1, + expectedSrcAddr: header.IPv6Any, maxRtrSolicit: 2, rtrSolicitInt: time.Second, effectiveRtrSolicitInt: time.Second, @@ -3457,7 +3516,7 @@ func TestRouterSolicitation(t *testing.T) { t.Run(test.name, func(t *testing.T) { t.Parallel() e := channelLinkWithHeaderLength{ - Endpoint: channel.New(int(test.maxRtrSolicit), 1280, linkAddr1), + Endpoint: channel.New(int(test.maxRtrSolicit), 1280, test.linkAddr), headerLength: test.linkHeaderLen, } e.Endpoint.LinkEPCapabilities |= stack.CapabilityResolutionRequired @@ -3481,10 +3540,10 @@ func TestRouterSolicitation(t *testing.T) { checker.IPv6(t, p.Pkt.Header.View(), - checker.SrcAddr(header.IPv6Any), + checker.SrcAddr(test.expectedSrcAddr), checker.DstAddr(header.IPv6AllRoutersMulticastAddress), checker.TTL(header.NDPHopLimit), - checker.NDPRS(), + checker.NDPRS(checker.NDPRSOptions(test.expectedNDPOpts)), ) if l, want := p.Pkt.Header.AvailableLength(), int(test.linkHeaderLen); l != want { @@ -3510,13 +3569,19 @@ func TestRouterSolicitation(t *testing.T) { t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) } - // Make sure each RS got sent at the right - // times. + if addr := test.nicAddr; addr != "" { + if err := s.AddAddress(nicID, header.IPv6ProtocolNumber, addr); err != nil { + t.Fatalf("AddAddress(%d, %d, %s) = %s", nicID, header.IPv6ProtocolNumber, addr, err) + } + } + + // Make sure each RS is sent at the right time. remaining := test.maxRtrSolicit if remaining > 0 { waitForPkt(test.effectiveMaxRtrSolicitDelay + defaultAsyncEventTimeout) remaining-- } + for ; remaining > 0; remaining-- { waitForNothing(test.effectiveRtrSolicitInt - defaultTimeout) waitForPkt(defaultAsyncEventTimeout) @@ -3550,17 +3615,19 @@ func TestStopStartSolicitingRouters(t *testing.T) { tests := []struct { name string startFn func(t *testing.T, s *stack.Stack) - stopFn func(t *testing.T, s *stack.Stack) + // first is used to tell stopFn that it is being called for the first time + // after router solicitations were last enabled. + stopFn func(t *testing.T, s *stack.Stack, first bool) }{ // Tests that when forwarding is enabled or disabled, router solicitations // are stopped or started, respectively. { - name: "Forwarding enabled and disabled", + name: "Enable and disable forwarding", startFn: func(t *testing.T, s *stack.Stack) { t.Helper() s.SetForwarding(false) }, - stopFn: func(t *testing.T, s *stack.Stack) { + stopFn: func(t *testing.T, s *stack.Stack, _ bool) { t.Helper() s.SetForwarding(true) }, @@ -3569,7 +3636,7 @@ func TestStopStartSolicitingRouters(t *testing.T) { // Tests that when a NIC is enabled or disabled, router solicitations // are started or stopped, respectively. { - name: "NIC disabled and enabled", + name: "Enable and disable NIC", startFn: func(t *testing.T, s *stack.Stack) { t.Helper() @@ -3577,7 +3644,7 @@ func TestStopStartSolicitingRouters(t *testing.T) { t.Fatalf("s.EnableNIC(%d): %s", nicID, err) } }, - stopFn: func(t *testing.T, s *stack.Stack) { + stopFn: func(t *testing.T, s *stack.Stack, _ bool) { t.Helper() if err := s.DisableNIC(nicID); err != nil { @@ -3585,6 +3652,25 @@ func TestStopStartSolicitingRouters(t *testing.T) { } }, }, + + // Tests that when a NIC is removed, router solicitations are stopped. We + // cannot start router solications on a removed NIC. + { + name: "Remove NIC", + stopFn: func(t *testing.T, s *stack.Stack, first bool) { + t.Helper() + + // Only try to remove the NIC the first time stopFn is called since it's + // impossible to remove an already removed NIC. + if !first { + return + } + + if err := s.RemoveNIC(nicID); err != nil { + t.Fatalf("s.RemoveNIC(%d): %s", nicID, err) + } + }, + }, } for _, test := range tests { @@ -3623,7 +3709,7 @@ func TestStopStartSolicitingRouters(t *testing.T) { } // Stop soliciting routers. - test.stopFn(t, s) + test.stopFn(t, s, true /* first */) ctx, cancel := context.WithTimeout(context.Background(), delay+defaultTimeout) defer cancel() if _, ok := e.ReadContext(ctx); ok { @@ -3637,13 +3723,18 @@ func TestStopStartSolicitingRouters(t *testing.T) { // Stopping router solicitations after it has already been stopped should // do nothing. - test.stopFn(t, s) + test.stopFn(t, s, false /* first */) ctx, cancel = context.WithTimeout(context.Background(), delay+defaultTimeout) defer cancel() if _, ok := e.ReadContext(ctx); ok { t.Fatal("unexpectedly got a packet after router solicitation has been stopepd") } + // If test.startFn is nil, there is no way to restart router solications. + if test.startFn == nil { + return + } + // Start soliciting routers. test.startFn(t, s) waitForPkt(delay + defaultAsyncEventTimeout) diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 46d3a6646..b6fa647ea 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -15,6 +15,7 @@ package stack import ( + "fmt" "log" "reflect" "sort" @@ -54,7 +55,7 @@ type NIC struct { primary map[tcpip.NetworkProtocolNumber][]*referencedNetworkEndpoint endpoints map[NetworkEndpointID]*referencedNetworkEndpoint addressRanges []tcpip.Subnet - mcastJoins map[NetworkEndpointID]int32 + mcastJoins map[NetworkEndpointID]uint32 // packetEPs is protected by mu, but the contained PacketEndpoint // values are not. packetEPs map[tcpip.NetworkProtocolNumber][]PacketEndpoint @@ -121,15 +122,15 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC } nic.mu.primary = make(map[tcpip.NetworkProtocolNumber][]*referencedNetworkEndpoint) nic.mu.endpoints = make(map[NetworkEndpointID]*referencedNetworkEndpoint) - nic.mu.mcastJoins = make(map[NetworkEndpointID]int32) + nic.mu.mcastJoins = make(map[NetworkEndpointID]uint32) nic.mu.packetEPs = make(map[tcpip.NetworkProtocolNumber][]PacketEndpoint) nic.mu.ndp = ndpState{ - nic: nic, - configs: stack.ndpConfigs, - dad: make(map[tcpip.Address]dadState), - defaultRouters: make(map[tcpip.Address]defaultRouterState), - onLinkPrefixes: make(map[tcpip.Subnet]onLinkPrefixState), - autoGenAddresses: make(map[tcpip.Address]autoGenAddressState), + nic: nic, + configs: stack.ndpConfigs, + dad: make(map[tcpip.Address]dadState), + defaultRouters: make(map[tcpip.Address]defaultRouterState), + onLinkPrefixes: make(map[tcpip.Subnet]onLinkPrefixState), + slaacPrefixes: make(map[tcpip.Subnet]slaacPrefixState), } // Register supported packet endpoint protocols. @@ -165,8 +166,17 @@ func (n *NIC) disable() *tcpip.Error { } n.mu.Lock() - defer n.mu.Unlock() + err := n.disableLocked() + n.mu.Unlock() + return err +} +// disableLocked disables n. +// +// It undoes the work done by enable. +// +// n MUST be locked. +func (n *NIC) disableLocked() *tcpip.Error { if !n.mu.enabled { return nil } @@ -189,7 +199,7 @@ func (n *NIC) disable() *tcpip.Error { } // The NIC may have already left the multicast group. - if err := n.leaveGroupLocked(header.IPv6AllNodesMulticastAddress); err != nil && err != tcpip.ErrBadLocalAddress { + if err := n.leaveGroupLocked(header.IPv6AllNodesMulticastAddress, false /* force */); err != nil && err != tcpip.ErrBadLocalAddress { return err } } @@ -305,24 +315,33 @@ func (n *NIC) remove() *tcpip.Error { n.mu.Lock() defer n.mu.Unlock() - // Detach from link endpoint, so no packet comes in. - n.linkEP.Attach(nil) + n.disableLocked() + + // TODO(b/151378115): come up with a better way to pick an error than the + // first one. + var err *tcpip.Error + + // Forcefully leave multicast groups. + for nid := range n.mu.mcastJoins { + if tempErr := n.leaveGroupLocked(nid.LocalAddress, true /* force */); tempErr != nil && err == nil { + err = tempErr + } + } // Remove permanent and permanentTentative addresses, so no packet goes out. - var errs []*tcpip.Error for nid, ref := range n.mu.endpoints { switch ref.getKind() { case permanentTentative, permanent: - if err := n.removePermanentAddressLocked(nid.LocalAddress); err != nil { - errs = append(errs, err) + if tempErr := n.removePermanentAddressLocked(nid.LocalAddress); tempErr != nil && err == nil { + err = tempErr } } } - if len(errs) > 0 { - return errs[0] - } - return nil + // Detach from link endpoint, so no packet comes in. + n.linkEP.Attach(nil) + + return err } // becomeIPv6Router transitions n into an IPv6 router. @@ -451,7 +470,7 @@ func (n *NIC) primaryIPv6Endpoint(remoteAddr tcpip.Address) *referencedNetworkEn cs := make([]ipv6AddrCandidate, 0, len(primaryAddrs)) for _, r := range primaryAddrs { // If r is not valid for outgoing connections, it is not a valid endpoint. - if !r.isValidForOutgoing() { + if !r.isValidForOutgoingRLocked() { continue } @@ -969,6 +988,7 @@ func (n *NIC) removeEndpointLocked(r *referencedNetworkEndpoint) { for i, ref := range refs { if ref == r { n.mu.primary[r.protocol] = append(refs[:i], refs[i+1:]...) + refs[len(refs)-1] = nil break } } @@ -996,8 +1016,7 @@ func (n *NIC) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error { isIPv6Unicast := r.protocol == header.IPv6ProtocolNumber && header.IsV6UnicastAddress(addr) if isIPv6Unicast { - // If we are removing a tentative IPv6 unicast address, stop - // DAD. + // If we are removing a tentative IPv6 unicast address, stop DAD. if kind == permanentTentative { n.mu.ndp.stopDuplicateAddressDetection(addr) } @@ -1005,7 +1024,10 @@ func (n *NIC) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error { // If we are removing an address generated via SLAAC, cleanup // its SLAAC resources and notify the integrator. if r.configType == slaac { - n.mu.ndp.cleanupAutoGenAddrResourcesAndNotify(addr) + n.mu.ndp.cleanupSLAACAddrResourcesAndNotify(tcpip.AddressWithPrefix{ + Address: addr, + PrefixLen: r.ep.PrefixLen(), + }) } } @@ -1019,9 +1041,12 @@ func (n *NIC) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error { // If we are removing an IPv6 unicast address, leave the solicited-node // multicast address. + // + // We ignore the tcpip.ErrBadLocalAddress error because the solicited-node + // multicast group may be left by user action. if isIPv6Unicast { snmc := header.SolicitedNodeAddr(addr) - if err := n.leaveGroupLocked(snmc); err != nil { + if err := n.leaveGroupLocked(snmc, false /* force */); err != nil && err != tcpip.ErrBadLocalAddress { return err } } @@ -1081,26 +1106,31 @@ func (n *NIC) leaveGroup(addr tcpip.Address) *tcpip.Error { n.mu.Lock() defer n.mu.Unlock() - return n.leaveGroupLocked(addr) + return n.leaveGroupLocked(addr, false /* force */) } // 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 { +// +// If force is true, then the count for the multicast addres is ignored and the +// endpoint will be removed immediately. +func (n *NIC) leaveGroupLocked(addr tcpip.Address, force bool) *tcpip.Error { id := NetworkEndpointID{addr} - joins := n.mu.mcastJoins[id] - switch joins { - case 0: + joins, ok := n.mu.mcastJoins[id] + if !ok { // There are no joins with this address on this NIC. return tcpip.ErrBadLocalAddress - case 1: - // This is the last one, clean up. - if err := n.removePermanentAddressLocked(addr); err != nil { - return err - } } - n.mu.mcastJoins[id] = joins - 1 + + joins-- + if force || joins == 0 { + // There are no outstanding joins or we are forced to leave, clean up. + delete(n.mu.mcastJoins, id) + return n.removePermanentAddressLocked(addr) + } + + n.mu.mcastJoins[id] = joins return nil } @@ -1113,9 +1143,10 @@ func (n *NIC) isInGroup(addr tcpip.Address) bool { return joins != 0 } -func handlePacket(protocol tcpip.NetworkProtocolNumber, dst, src tcpip.Address, localLinkAddr, remotelinkAddr tcpip.LinkAddress, ref *referencedNetworkEndpoint, pkt tcpip.PacketBuffer) { +func handlePacket(protocol tcpip.NetworkProtocolNumber, dst, src tcpip.Address, localLinkAddr, remotelinkAddr tcpip.LinkAddress, ref *referencedNetworkEndpoint, pkt PacketBuffer) { r := makeRoute(protocol, dst, src, localLinkAddr, ref, false /* handleLocal */, false /* multicastLoop */) r.RemoteLinkAddress = remotelinkAddr + ref.ep.HandlePacket(&r, pkt) ref.decRef() } @@ -1126,7 +1157,7 @@ func handlePacket(protocol tcpip.NetworkProtocolNumber, dst, src tcpip.Address, // Note that the ownership of the slice backing vv is retained by the caller. // This rule applies only to the slice itself, not to the items of the slice; // the ownership of the items is not retained by the caller. -func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) { +func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) { n.mu.RLock() enabled := n.mu.enabled // If the NIC is not yet enabled, don't receive any packets. @@ -1186,6 +1217,16 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link n.stack.stats.IP.InvalidSourceAddressesReceived.Increment() return } + + // TODO(gvisor.dev/issue/170): Not supporting iptables for IPv6 yet. + if protocol == header.IPv4ProtocolNumber { + ipt := n.stack.IPTables() + if ok := ipt.Check(Prerouting, pkt); !ok { + // iptables is telling us to drop the packet. + return + } + } + if ref := n.getRef(protocol, dst); ref != nil { handlePacket(protocol, dst, src, linkEP.LinkAddress(), remote, ref, pkt) return @@ -1201,10 +1242,6 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link n.stack.stats.IP.InvalidDestinationAddressesReceived.Increment() return } - defer r.Release() - - r.LocalLinkAddress = n.linkEP.LinkAddress() - r.RemoteLinkAddress = remote // Found a NIC. n := r.ref.nic @@ -1213,24 +1250,33 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link ok = ok && ref.isValidForOutgoingRLocked() && ref.tryIncRef() n.mu.RUnlock() if ok { + r.LocalLinkAddress = n.linkEP.LinkAddress() + r.RemoteLinkAddress = remote r.RemoteAddress = src // TODO(b/123449044): Update the source NIC as well. ref.ep.HandlePacket(&r, pkt) ref.decRef() - } else { - // n doesn't have a destination endpoint. - // Send the packet out of n. - pkt.Header = buffer.NewPrependableFromView(pkt.Data.First()) - pkt.Data.RemoveFirst() - - // TODO(b/128629022): use route.WritePacket. - if err := n.linkEP.WritePacket(&r, nil /* gso */, protocol, pkt); err != nil { - r.Stats().IP.OutgoingPacketErrors.Increment() - } else { - n.stats.Tx.Packets.Increment() - n.stats.Tx.Bytes.IncrementBy(uint64(pkt.Header.UsedLength() + pkt.Data.Size())) + r.Release() + return + } + + // n doesn't have a destination endpoint. + // Send the packet out of n. + // TODO(b/128629022): move this logic to route.WritePacket. + if ch, err := r.Resolve(nil); err != nil { + if err == tcpip.ErrWouldBlock { + n.stack.forwarder.enqueue(ch, n, &r, protocol, pkt) + // forwarder will release route. + return } + n.stack.stats.IP.InvalidDestinationAddressesReceived.Increment() + r.Release() + return } + + // The link-address resolution finished immediately. + n.forwardPacket(&r, protocol, pkt) + r.Release() return } @@ -1240,9 +1286,38 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link } } +func (n *NIC) forwardPacket(r *Route, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) { + // TODO(b/143425874) Decrease the TTL field in forwarded packets. + + firstData := pkt.Data.First() + pkt.Data.RemoveFirst() + + if linkHeaderLen := int(n.linkEP.MaxHeaderLength()); linkHeaderLen == 0 { + pkt.Header = buffer.NewPrependableFromView(firstData) + } else { + firstDataLen := len(firstData) + + // pkt.Header should have enough capacity to hold n.linkEP's headers. + pkt.Header = buffer.NewPrependable(firstDataLen + linkHeaderLen) + + // TODO(b/151227689): avoid copying the packet when forwarding + if n := copy(pkt.Header.Prepend(firstDataLen), firstData); n != firstDataLen { + panic(fmt.Sprintf("copied %d bytes, expected %d", n, firstDataLen)) + } + } + + if err := n.linkEP.WritePacket(r, nil /* gso */, protocol, pkt); err != nil { + r.Stats().IP.OutgoingPacketErrors.Increment() + return + } + + n.stats.Tx.Packets.Increment() + n.stats.Tx.Bytes.IncrementBy(uint64(pkt.Header.UsedLength() + pkt.Data.Size())) +} + // DeliverTransportPacket delivers the packets to the appropriate transport // protocol endpoint. -func (n *NIC) DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt tcpip.PacketBuffer) { +func (n *NIC) DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt PacketBuffer) { state, ok := n.stack.transportProtocols[protocol] if !ok { n.stack.stats.UnknownProtocolRcvdPackets.Increment() @@ -1288,7 +1363,7 @@ func (n *NIC) DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolN // DeliverTransportControlPacket delivers control packets to the appropriate // transport protocol endpoint. -func (n *NIC) DeliverTransportControlPacket(local, remote tcpip.Address, net tcpip.NetworkProtocolNumber, trans tcpip.TransportProtocolNumber, typ ControlType, extra uint32, pkt tcpip.PacketBuffer) { +func (n *NIC) DeliverTransportControlPacket(local, remote tcpip.Address, net tcpip.NetworkProtocolNumber, trans tcpip.TransportProtocolNumber, typ ControlType, extra uint32, pkt PacketBuffer) { state, ok := n.stack.transportProtocols[trans] if !ok { return diff --git a/pkg/tcpip/stack/nic_test.go b/pkg/tcpip/stack/nic_test.go index edaee3b86..d672fc157 100644 --- a/pkg/tcpip/stack/nic_test.go +++ b/pkg/tcpip/stack/nic_test.go @@ -17,7 +17,6 @@ package stack import ( "testing" - "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" ) @@ -45,7 +44,7 @@ func TestDisabledRxStatsWhenNICDisabled(t *testing.T) { t.FailNow() } - nic.DeliverNetworkPacket(nil, "", "", 0, tcpip.PacketBuffer{Data: buffer.View([]byte{1, 2, 3, 4}).ToVectorisedView()}) + nic.DeliverNetworkPacket(nil, "", "", 0, PacketBuffer{Data: buffer.View([]byte{1, 2, 3, 4}).ToVectorisedView()}) if got := nic.stats.DisabledRx.Packets.Value(); got != 1 { t.Errorf("got DisabledRx.Packets = %d, want = 1", got) diff --git a/pkg/tcpip/stack/packet_buffer.go b/pkg/tcpip/stack/packet_buffer.go new file mode 100644 index 000000000..9505a4e92 --- /dev/null +++ b/pkg/tcpip/stack/packet_buffer.go @@ -0,0 +1,71 @@ +// 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 + +import "gvisor.dev/gvisor/pkg/tcpip/buffer" + +// A PacketBuffer contains all the data of a network packet. +// +// As a PacketBuffer traverses up the stack, it may be necessary to pass it to +// multiple endpoints. Clone() should be called in such cases so that +// modifications to the Data field do not affect other copies. +// +// +stateify savable +type PacketBuffer struct { + // Data holds the payload of the packet. For inbound packets, it also + // holds the headers, which are consumed as the packet moves up the + // stack. Headers are guaranteed not to be split across views. + // + // The bytes backing Data are immutable, but Data itself may be trimmed + // or otherwise modified. + Data buffer.VectorisedView + + // DataOffset is used for GSO output. It is the offset into the Data + // field where the payload of this packet starts. + DataOffset int + + // DataSize is used for GSO output. It is the size of this packet's + // payload. + DataSize int + + // Header holds the headers of outbound packets. As a packet is passed + // down the stack, each layer adds to Header. + Header buffer.Prependable + + // These fields are used by both inbound and outbound packets. They + // typically overlap with the Data and Header fields. + // + // The bytes backing these views are immutable. Each field may be nil + // if either it has not been set yet or no such header exists (e.g. + // packets sent via loopback may not have a link header). + // + // These fields may be Views into other slices (either Data or Header). + // SR dosen't support this, so deep copies are necessary in some cases. + LinkHeader buffer.View + NetworkHeader buffer.View + TransportHeader buffer.View + + // Hash is the transport layer hash of this packet. A value of zero + // indicates no valid hash has been set. + Hash uint32 +} + +// Clone makes a copy of pk. It clones the Data field, which creates a new +// VectorisedView but does not deep copy the underlying bytes. +// +// Clone also does not deep copy any of its other fields. +func (pk PacketBuffer) Clone() PacketBuffer { + pk.Data = pk.Data.Clone(nil) + return pk +} diff --git a/pkg/tcpip/stack/packet_buffer_state.go b/pkg/tcpip/stack/packet_buffer_state.go new file mode 100644 index 000000000..0c6b7924c --- /dev/null +++ b/pkg/tcpip/stack/packet_buffer_state.go @@ -0,0 +1,27 @@ +// 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 + +import "gvisor.dev/gvisor/pkg/tcpip/buffer" + +// beforeSave is invoked by stateify. +func (pk *PacketBuffer) beforeSave() { + // Non-Data fields may be slices of the Data field. This causes + // problems for SR, so during save we make each header independent. + pk.Header = pk.Header.DeepCopy() + pk.LinkHeader = append(buffer.View(nil), pk.LinkHeader...) + pk.NetworkHeader = append(buffer.View(nil), pk.NetworkHeader...) + pk.TransportHeader = append(buffer.View(nil), pk.TransportHeader...) +} diff --git a/pkg/tcpip/stack/rand.go b/pkg/tcpip/stack/rand.go new file mode 100644 index 000000000..421fb5c15 --- /dev/null +++ b/pkg/tcpip/stack/rand.go @@ -0,0 +1,40 @@ +// 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 stack + +import ( + mathrand "math/rand" + + "gvisor.dev/gvisor/pkg/sync" +) + +// lockedRandomSource provides a threadsafe rand.Source. +type lockedRandomSource struct { + mu sync.Mutex + src mathrand.Source +} + +func (r *lockedRandomSource) Int63() (n int64) { + r.mu.Lock() + n = r.src.Int63() + r.mu.Unlock() + return n +} + +func (r *lockedRandomSource) Seed(seed int64) { + r.mu.Lock() + r.src.Seed(seed) + r.mu.Unlock() +} diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go index f9fd8f18f..ac043b722 100644 --- a/pkg/tcpip/stack/registration.go +++ b/pkg/tcpip/stack/registration.go @@ -67,12 +67,12 @@ type TransportEndpoint interface { // this transport endpoint. It sets pkt.TransportHeader. // // HandlePacket takes ownership of pkt. - HandlePacket(r *Route, id TransportEndpointID, pkt tcpip.PacketBuffer) + HandlePacket(r *Route, id TransportEndpointID, pkt PacketBuffer) // HandleControlPacket is called by the stack when new control (e.g. // ICMP) packets arrive to this transport endpoint. // HandleControlPacket takes ownership of pkt. - HandleControlPacket(id TransportEndpointID, typ ControlType, extra uint32, pkt tcpip.PacketBuffer) + HandleControlPacket(id TransportEndpointID, typ ControlType, extra uint32, pkt PacketBuffer) // Abort initiates an expedited endpoint teardown. It puts the endpoint // in a closed state and frees all resources associated with it. This @@ -100,7 +100,7 @@ type RawTransportEndpoint interface { // layer up. // // HandlePacket takes ownership of pkt. - HandlePacket(r *Route, pkt tcpip.PacketBuffer) + HandlePacket(r *Route, pkt PacketBuffer) } // PacketEndpoint is the interface that needs to be implemented by packet @@ -118,7 +118,7 @@ type PacketEndpoint interface { // should construct its own ethernet header for applications. // // HandlePacket takes ownership of pkt. - HandlePacket(nicID tcpip.NICID, addr tcpip.LinkAddress, netProto tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) + HandlePacket(nicID tcpip.NICID, addr tcpip.LinkAddress, netProto tcpip.NetworkProtocolNumber, pkt PacketBuffer) } // TransportProtocol is the interface that needs to be implemented by transport @@ -150,7 +150,7 @@ type TransportProtocol interface { // stats purposes only). // // HandleUnknownDestinationPacket takes ownership of pkt. - HandleUnknownDestinationPacket(r *Route, id TransportEndpointID, pkt tcpip.PacketBuffer) bool + HandleUnknownDestinationPacket(r *Route, id TransportEndpointID, pkt PacketBuffer) bool // SetOption allows enabling/disabling protocol specific features. // SetOption returns an error if the option is not supported or the @@ -180,7 +180,7 @@ type TransportDispatcher interface { // pkt.NetworkHeader must be set before calling DeliverTransportPacket. // // DeliverTransportPacket takes ownership of pkt. - DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt tcpip.PacketBuffer) + DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt PacketBuffer) // DeliverTransportControlPacket delivers control packets to the // appropriate transport protocol endpoint. @@ -189,7 +189,7 @@ type TransportDispatcher interface { // DeliverTransportControlPacket. // // DeliverTransportControlPacket takes ownership of pkt. - DeliverTransportControlPacket(local, remote tcpip.Address, net tcpip.NetworkProtocolNumber, trans tcpip.TransportProtocolNumber, typ ControlType, extra uint32, pkt tcpip.PacketBuffer) + DeliverTransportControlPacket(local, remote tcpip.Address, net tcpip.NetworkProtocolNumber, trans tcpip.TransportProtocolNumber, typ ControlType, extra uint32, pkt PacketBuffer) } // PacketLooping specifies where an outbound packet should be sent. @@ -242,15 +242,15 @@ type NetworkEndpoint interface { // WritePacket writes a packet to the given destination address and // protocol. It sets pkt.NetworkHeader. pkt.TransportHeader must have // already been set. - WritePacket(r *Route, gso *GSO, params NetworkHeaderParams, pkt tcpip.PacketBuffer) *tcpip.Error + WritePacket(r *Route, gso *GSO, params NetworkHeaderParams, pkt PacketBuffer) *tcpip.Error // WritePackets writes packets to the given destination address and // protocol. pkts must not be zero length. - WritePackets(r *Route, gso *GSO, pkts []tcpip.PacketBuffer, params NetworkHeaderParams) (int, *tcpip.Error) + WritePackets(r *Route, gso *GSO, pkts []PacketBuffer, params NetworkHeaderParams) (int, *tcpip.Error) // WriteHeaderIncludedPacket writes a packet that includes a network // header to the given destination address. - WriteHeaderIncludedPacket(r *Route, pkt tcpip.PacketBuffer) *tcpip.Error + WriteHeaderIncludedPacket(r *Route, pkt PacketBuffer) *tcpip.Error // ID returns the network protocol endpoint ID. ID() *NetworkEndpointID @@ -265,7 +265,7 @@ type NetworkEndpoint interface { // this network endpoint. It sets pkt.NetworkHeader. // // HandlePacket takes ownership of pkt. - HandlePacket(r *Route, pkt tcpip.PacketBuffer) + HandlePacket(r *Route, pkt PacketBuffer) // Close is called when the endpoint is reomved from a stack. Close() @@ -322,7 +322,7 @@ type NetworkDispatcher interface { // packets sent via loopback), and won't have the field set. // // DeliverNetworkPacket takes ownership of pkt. - DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) + DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) } // LinkEndpointCapabilities is the type associated with the capabilities @@ -354,7 +354,7 @@ const ( // LinkEndpoint is the interface implemented by data link layer protocols (e.g., // ethernet, loopback, raw) and used by network layer protocols to send packets // out through the implementer's data link endpoint. When a link header exists, -// it sets each tcpip.PacketBuffer's LinkHeader field before passing it up the +// it sets each PacketBuffer's LinkHeader field before passing it up the // stack. type LinkEndpoint interface { // MTU is the maximum transmission unit for this endpoint. This is @@ -385,7 +385,7 @@ type LinkEndpoint interface { // To participate in transparent bridging, a LinkEndpoint implementation // should call eth.Encode with header.EthernetFields.SrcAddr set to // r.LocalLinkAddress if it is provided. - WritePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) *tcpip.Error + WritePacket(r *Route, gso *GSO, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) *tcpip.Error // WritePackets writes packets with the given protocol through the // given route. pkts must not be zero length. @@ -393,7 +393,7 @@ type LinkEndpoint interface { // Right now, WritePackets is used only when the software segmentation // offload is enabled. If it will be used for something else, it may // require to change syscall filters. - WritePackets(r *Route, gso *GSO, pkts []tcpip.PacketBuffer, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) + WritePackets(r *Route, gso *GSO, pkts []PacketBuffer, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) // WriteRawPacket writes a packet directly to the link. The packet // should already have an ethernet header. @@ -401,6 +401,9 @@ type LinkEndpoint interface { // Attach attaches the data link layer endpoint to the network-layer // dispatcher of the stack. + // + // Attach will be called with a nil dispatcher if the receiver's associated + // NIC is being removed. Attach(dispatcher NetworkDispatcher) // IsAttached returns whether a NetworkDispatcher is attached to the @@ -423,7 +426,7 @@ type InjectableLinkEndpoint interface { LinkEndpoint // InjectInbound injects an inbound packet. - InjectInbound(protocol tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) + InjectInbound(protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) // InjectOutbound writes a fully formed outbound packet directly to the // link. diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go index f565aafb2..9fbe8a411 100644 --- a/pkg/tcpip/stack/route.go +++ b/pkg/tcpip/stack/route.go @@ -153,7 +153,7 @@ func (r *Route) IsResolutionRequired() bool { } // WritePacket writes the packet through the given route. -func (r *Route) WritePacket(gso *GSO, params NetworkHeaderParams, pkt tcpip.PacketBuffer) *tcpip.Error { +func (r *Route) WritePacket(gso *GSO, params NetworkHeaderParams, pkt PacketBuffer) *tcpip.Error { if !r.ref.isValidForOutgoing() { return tcpip.ErrInvalidEndpointState } @@ -169,7 +169,7 @@ func (r *Route) WritePacket(gso *GSO, params NetworkHeaderParams, pkt tcpip.Pack } // WritePackets writes the set of packets through the given route. -func (r *Route) WritePackets(gso *GSO, pkts []tcpip.PacketBuffer, params NetworkHeaderParams) (int, *tcpip.Error) { +func (r *Route) WritePackets(gso *GSO, pkts []PacketBuffer, params NetworkHeaderParams) (int, *tcpip.Error) { if !r.ref.isValidForOutgoing() { return 0, tcpip.ErrInvalidEndpointState } @@ -190,7 +190,7 @@ func (r *Route) WritePackets(gso *GSO, pkts []tcpip.PacketBuffer, params Network // WriteHeaderIncludedPacket writes a packet already containing a network // header through the given route. -func (r *Route) WriteHeaderIncludedPacket(pkt tcpip.PacketBuffer) *tcpip.Error { +func (r *Route) WriteHeaderIncludedPacket(pkt PacketBuffer) *tcpip.Error { if !r.ref.isValidForOutgoing() { return tcpip.ErrInvalidEndpointState } diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index ebb6c5e3b..41398a1b6 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -20,7 +20,9 @@ package stack import ( + "bytes" "encoding/binary" + mathrand "math/rand" "sync/atomic" "time" @@ -31,7 +33,6 @@ import ( "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" - "gvisor.dev/gvisor/pkg/tcpip/iptables" "gvisor.dev/gvisor/pkg/tcpip/ports" "gvisor.dev/gvisor/pkg/tcpip/seqnum" "gvisor.dev/gvisor/pkg/waiter" @@ -51,7 +52,7 @@ const ( type transportProtocolState struct { proto TransportProtocol - defaultHandler func(r *Route, id TransportEndpointID, pkt tcpip.PacketBuffer) bool + defaultHandler func(r *Route, id TransportEndpointID, pkt PacketBuffer) bool } // TCPProbeFunc is the expected function type for a TCP probe function to be @@ -428,7 +429,7 @@ type Stack struct { // tables are the iptables packet filtering and manipulation rules. The are // protected by tablesMu.` - tables iptables.IPTables + tables IPTables // resumableEndpoints is a list of endpoints that need to be resumed if the // stack is being restored. @@ -462,6 +463,14 @@ type Stack struct { // opaqueIIDOpts hold the options for generating opaque interface identifiers // (IIDs) as outlined by RFC 7217. opaqueIIDOpts OpaqueInterfaceIdentifierOptions + + // forwarder holds the packets that wait for their link-address resolutions + // to complete, and forwards them when each resolution is done. + forwarder *forwardQueue + + // randomGenerator is an injectable pseudo random generator that can be + // used when a random number is required. + randomGenerator *mathrand.Rand } // UniqueID is an abstract generator of unique identifiers. @@ -522,9 +531,16 @@ type Options struct { // this is non-nil. RawFactory RawFactory - // OpaqueIIDOpts hold the options for generating opaque interface identifiers - // (IIDs) as outlined by RFC 7217. + // OpaqueIIDOpts hold the options for generating opaque interface + // identifiers (IIDs) as outlined by RFC 7217. OpaqueIIDOpts OpaqueInterfaceIdentifierOptions + + // RandSource is an optional source to use to generate random + // numbers. If omitted it defaults to a Source seeded by the data + // returned by rand.Read(). + // + // RandSource must be thread-safe. + RandSource mathrand.Source } // TransportEndpointInfo holds useful information about a transport endpoint @@ -551,11 +567,13 @@ type TransportEndpointInfo struct { RegisterNICID tcpip.NICID } -// AddrNetProto unwraps the specified address if it is a V4-mapped V6 address -// and returns the network protocol number to be used to communicate with the -// specified address. It returns an error if the passed address is incompatible -// with the receiver. -func (e *TransportEndpointInfo) AddrNetProto(addr tcpip.FullAddress, v6only bool) (tcpip.FullAddress, tcpip.NetworkProtocolNumber, *tcpip.Error) { +// AddrNetProtoLocked unwraps the specified address if it is a V4-mapped V6 +// address and returns the network protocol number to be used to communicate +// with the specified address. It returns an error if the passed address is +// incompatible with the receiver. +// +// Preconditon: the parent endpoint mu must be held while calling this method. +func (e *TransportEndpointInfo) AddrNetProtoLocked(addr tcpip.FullAddress, v6only bool) (tcpip.FullAddress, tcpip.NetworkProtocolNumber, *tcpip.Error) { netProto := e.NetProto switch len(addr.Addr) { case header.IPv4AddressSize: @@ -618,6 +636,13 @@ func New(opts Options) *Stack { opts.UniqueID = new(uniqueIDGenerator) } + randSrc := opts.RandSource + if randSrc == nil { + // Source provided by mathrand.NewSource is not thread-safe so + // we wrap it in a simple thread-safe version. + randSrc = &lockedRandomSource{src: mathrand.NewSource(generateRandInt64())} + } + // Make sure opts.NDPConfigs contains valid values only. opts.NDPConfigs.validate() @@ -639,6 +664,8 @@ func New(opts Options) *Stack { uniqueIDGenerator: opts.UniqueID, ndpDisp: opts.NDPDisp, opaqueIIDOpts: opts.OpaqueIIDOpts, + forwarder: newForwardQueue(), + randomGenerator: mathrand.New(randSrc), } // Add specified network protocols. @@ -731,7 +758,7 @@ func (s *Stack) TransportProtocolOption(transport tcpip.TransportProtocolNumber, // // It must be called only during initialization of the stack. Changing it as the // stack is operating is not supported. -func (s *Stack) SetTransportProtocolHandler(p tcpip.TransportProtocolNumber, h func(*Route, TransportEndpointID, tcpip.PacketBuffer) bool) { +func (s *Stack) SetTransportProtocolHandler(p tcpip.TransportProtocolNumber, h func(*Route, TransportEndpointID, PacketBuffer) bool) { state := s.transportProtocols[p] if state != nil { state.defaultHandler = h @@ -1694,7 +1721,7 @@ func (s *Stack) IsInGroup(nicID tcpip.NICID, multicastAddr tcpip.Address) (bool, } // IPTables returns the stack's iptables. -func (s *Stack) IPTables() iptables.IPTables { +func (s *Stack) IPTables() IPTables { s.tablesMu.RLock() t := s.tables s.tablesMu.RUnlock() @@ -1702,7 +1729,7 @@ func (s *Stack) IPTables() iptables.IPTables { } // SetIPTables sets the stack's iptables. -func (s *Stack) SetIPTables(ipt iptables.IPTables) { +func (s *Stack) SetIPTables(ipt IPTables) { s.tablesMu.Lock() s.tables = ipt s.tablesMu.Unlock() @@ -1812,6 +1839,12 @@ func (s *Stack) Seed() uint32 { return s.seed } +// Rand returns a reference to a pseudo random generator that can be used +// to generate random numbers as required. +func (s *Stack) Rand() *mathrand.Rand { + return s.randomGenerator +} + func generateRandUint32() uint32 { b := make([]byte, 4) if _, err := rand.Read(b); err != nil { @@ -1819,3 +1852,16 @@ func generateRandUint32() uint32 { } return binary.LittleEndian.Uint32(b) } + +func generateRandInt64() int64 { + b := make([]byte, 8) + if _, err := rand.Read(b); err != nil { + panic(err) + } + buf := bytes.NewReader(b) + var v int64 + if err := binary.Read(buf, binary.LittleEndian, &v); err != nil { + panic(err) + } + return v +} diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index e15db40fb..555fcd92f 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -90,7 +90,7 @@ func (f *fakeNetworkEndpoint) ID() *stack.NetworkEndpointID { return &f.id } -func (f *fakeNetworkEndpoint) HandlePacket(r *stack.Route, pkt tcpip.PacketBuffer) { +func (f *fakeNetworkEndpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) { // Increment the received packet count in the protocol descriptor. f.proto.packetCount[int(f.id.LocalAddress[0])%len(f.proto.packetCount)]++ @@ -126,7 +126,7 @@ func (f *fakeNetworkEndpoint) Capabilities() stack.LinkEndpointCapabilities { return f.ep.Capabilities() } -func (f *fakeNetworkEndpoint) WritePacket(r *stack.Route, gso *stack.GSO, params stack.NetworkHeaderParams, pkt tcpip.PacketBuffer) *tcpip.Error { +func (f *fakeNetworkEndpoint) WritePacket(r *stack.Route, gso *stack.GSO, params stack.NetworkHeaderParams, pkt stack.PacketBuffer) *tcpip.Error { // Increment the sent packet count in the protocol descriptor. f.proto.sendPacketCount[int(r.RemoteAddress[0])%len(f.proto.sendPacketCount)]++ @@ -141,7 +141,7 @@ func (f *fakeNetworkEndpoint) WritePacket(r *stack.Route, gso *stack.GSO, params views := make([]buffer.View, 1, 1+len(pkt.Data.Views())) views[0] = pkt.Header.View() views = append(views, pkt.Data.Views()...) - f.HandlePacket(r, tcpip.PacketBuffer{ + f.HandlePacket(r, stack.PacketBuffer{ Data: buffer.NewVectorisedView(len(views[0])+pkt.Data.Size(), views), }) } @@ -153,11 +153,11 @@ func (f *fakeNetworkEndpoint) WritePacket(r *stack.Route, gso *stack.GSO, params } // WritePackets implements stack.LinkEndpoint.WritePackets. -func (f *fakeNetworkEndpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts []tcpip.PacketBuffer, params stack.NetworkHeaderParams) (int, *tcpip.Error) { +func (f *fakeNetworkEndpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts []stack.PacketBuffer, params stack.NetworkHeaderParams) (int, *tcpip.Error) { panic("not implemented") } -func (*fakeNetworkEndpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt tcpip.PacketBuffer) *tcpip.Error { +func (*fakeNetworkEndpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuffer) *tcpip.Error { return tcpip.ErrNotSupported } @@ -255,7 +255,7 @@ type linkEPWithMockedAttach struct { // Attach implements stack.LinkEndpoint.Attach. func (l *linkEPWithMockedAttach) Attach(d stack.NetworkDispatcher) { l.LinkEndpoint.Attach(d) - l.attached = true + l.attached = d != nil } func (l *linkEPWithMockedAttach) isAttached() bool { @@ -287,7 +287,7 @@ func TestNetworkReceive(t *testing.T) { // Make sure packet with wrong address is not delivered. buf[0] = 3 - ep.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + ep.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeNet.packetCount[1] != 0 { @@ -299,7 +299,7 @@ func TestNetworkReceive(t *testing.T) { // Make sure packet is delivered to first endpoint. buf[0] = 1 - ep.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + ep.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeNet.packetCount[1] != 1 { @@ -311,7 +311,7 @@ func TestNetworkReceive(t *testing.T) { // Make sure packet is delivered to second endpoint. buf[0] = 2 - ep.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + ep.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeNet.packetCount[1] != 1 { @@ -322,7 +322,7 @@ func TestNetworkReceive(t *testing.T) { } // Make sure packet is not delivered if protocol number is wrong. - ep.InjectInbound(fakeNetNumber-1, tcpip.PacketBuffer{ + ep.InjectInbound(fakeNetNumber-1, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeNet.packetCount[1] != 1 { @@ -334,7 +334,7 @@ func TestNetworkReceive(t *testing.T) { // Make sure packet that is too small is dropped. buf.CapLength(2) - ep.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + ep.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeNet.packetCount[1] != 1 { @@ -356,7 +356,7 @@ func sendTo(s *stack.Stack, addr tcpip.Address, payload buffer.View) *tcpip.Erro func send(r stack.Route, payload buffer.View) *tcpip.Error { hdr := buffer.NewPrependable(int(r.MaxHeaderLength())) - return r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: fakeTransNumber, TTL: 123, TOS: stack.DefaultTOS}, tcpip.PacketBuffer{ + return r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: fakeTransNumber, TTL: 123, TOS: stack.DefaultTOS}, stack.PacketBuffer{ Header: hdr, Data: payload.ToVectorisedView(), }) @@ -414,7 +414,7 @@ func testFailingRecv(t *testing.T, fakeNet *fakeNetworkProtocol, localAddrByte b func testRecvInternal(t *testing.T, fakeNet *fakeNetworkProtocol, localAddrByte byte, ep *channel.Endpoint, buf buffer.View, want int) { t.Helper() - ep.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + ep.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if got := fakeNet.PacketCount(localAddrByte); got != want { @@ -566,7 +566,7 @@ func TestAttachToLinkEndpointImmediately(t *testing.T) { t.Fatalf("CreateNICWithOptions(%d, _, %+v) = %s", nicID, test.nicOpts, err) } if !e.isAttached() { - t.Fatalf("link endpoint not attached to a network disatcher") + t.Fatal("link endpoint not attached to a network dispatcher") } }) } @@ -631,196 +631,240 @@ func TestDisabledNICsNICInfoAndCheckNIC(t *testing.T) { checkNIC(false) } -func TestRoutesWithDisabledNIC(t *testing.T) { - const unspecifiedNIC = 0 - const nicID1 = 1 - const nicID2 = 2 - +func TestRemoveUnknownNIC(t *testing.T) { s := stack.New(stack.Options{ NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, }) - ep1 := channel.New(0, defaultMTU, "") - if err := s.CreateNIC(nicID1, ep1); err != nil { - t.Fatalf("CreateNIC(%d, _): %s", nicID1, err) + if err := s.RemoveNIC(1); err != tcpip.ErrUnknownNICID { + t.Fatalf("got s.RemoveNIC(1) = %v, want = %s", err, tcpip.ErrUnknownNICID) } +} - addr1 := tcpip.Address("\x01") - if err := s.AddAddress(nicID1, fakeNetNumber, addr1); err != nil { - t.Fatalf("AddAddress(%d, %d, %s): %s", nicID1, fakeNetNumber, addr1, err) - } +func TestRemoveNIC(t *testing.T) { + const nicID = 1 + + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) - ep2 := channel.New(0, defaultMTU, "") - if err := s.CreateNIC(nicID2, ep2); err != nil { - t.Fatalf("CreateNIC(%d, _): %s", nicID2, err) + e := linkEPWithMockedAttach{ + LinkEndpoint: loopback.New(), + } + if err := s.CreateNIC(nicID, &e); err != nil { + t.Fatalf("CreateNIC(%d, _) = %s", nicID, err) } - addr2 := tcpip.Address("\x02") - if err := s.AddAddress(nicID2, fakeNetNumber, addr2); err != nil { - t.Fatalf("AddAddress(%d, %d, %s): %s", nicID2, fakeNetNumber, addr2, err) + // NIC should be present in NICInfo and attached to a NetworkDispatcher. + allNICInfo := s.NICInfo() + if _, ok := allNICInfo[nicID]; !ok { + t.Errorf("entry for %d missing from allNICInfo = %+v", nicID, allNICInfo) + } + if !e.isAttached() { + t.Fatal("link endpoint not attached to a network dispatcher") } - // Set a route table that sends all packets with odd destination - // addresses through the first NIC, and all even destination address - // through the second one. - { - subnet0, err := tcpip.NewSubnet("\x00", "\x01") - if err != nil { - t.Fatal(err) - } - subnet1, err := tcpip.NewSubnet("\x01", "\x01") - if err != nil { - t.Fatal(err) - } - s.SetRouteTable([]tcpip.Route{ - {Destination: subnet1, Gateway: "\x00", NIC: nicID1}, - {Destination: subnet0, Gateway: "\x00", NIC: nicID2}, - }) + // Removing a NIC should remove it from NICInfo and e should be detached from + // the NetworkDispatcher. + if err := s.RemoveNIC(nicID); err != nil { + t.Fatalf("s.RemoveNIC(%d): %s", nicID, err) + } + if nicInfo, ok := s.NICInfo()[nicID]; ok { + t.Errorf("got unexpected NICInfo entry for deleted NIC %d = %+v", nicID, nicInfo) } + if e.isAttached() { + t.Error("link endpoint for removed NIC still attached to a network dispatcher") + } +} - // Test routes to odd address. - testRoute(t, s, unspecifiedNIC, "", "\x05", addr1) - testRoute(t, s, unspecifiedNIC, addr1, "\x05", addr1) - testRoute(t, s, nicID1, addr1, "\x05", addr1) +func TestRouteWithDownNIC(t *testing.T) { + tests := []struct { + name string + downFn func(s *stack.Stack, nicID tcpip.NICID) *tcpip.Error + upFn func(s *stack.Stack, nicID tcpip.NICID) *tcpip.Error + }{ + { + name: "Disabled NIC", + downFn: (*stack.Stack).DisableNIC, + upFn: (*stack.Stack).EnableNIC, + }, + + // Once a NIC is removed, it cannot be brought up. + { + name: "Removed NIC", + downFn: (*stack.Stack).RemoveNIC, + }, + } - // Test routes to even address. - testRoute(t, s, unspecifiedNIC, "", "\x06", addr2) - testRoute(t, s, unspecifiedNIC, addr2, "\x06", addr2) - testRoute(t, s, nicID2, addr2, "\x06", addr2) - - // Disabling NIC1 should result in no routes to odd addresses. Routes to even - // addresses should continue to be available as NIC2 is still enabled. - if err := s.DisableNIC(nicID1); err != nil { - t.Fatalf("s.DisableNIC(%d): %s", nicID1, err) - } - nic1Dst := tcpip.Address("\x05") - testNoRoute(t, s, unspecifiedNIC, "", nic1Dst) - testNoRoute(t, s, unspecifiedNIC, addr1, nic1Dst) - testNoRoute(t, s, nicID1, addr1, nic1Dst) - nic2Dst := tcpip.Address("\x06") - testRoute(t, s, unspecifiedNIC, "", nic2Dst, addr2) - testRoute(t, s, unspecifiedNIC, addr2, nic2Dst, addr2) - testRoute(t, s, nicID2, addr2, nic2Dst, addr2) - - // Disabling NIC2 should result in no routes to even addresses. No route - // should be available to any address as routes to odd addresses were made - // unavailable by disabling NIC1 above. - if err := s.DisableNIC(nicID2); err != nil { - t.Fatalf("s.DisableNIC(%d): %s", nicID2, err) - } - testNoRoute(t, s, unspecifiedNIC, "", nic1Dst) - testNoRoute(t, s, unspecifiedNIC, addr1, nic1Dst) - testNoRoute(t, s, nicID1, addr1, nic1Dst) - testNoRoute(t, s, unspecifiedNIC, "", nic2Dst) - testNoRoute(t, s, unspecifiedNIC, addr2, nic2Dst) - testNoRoute(t, s, nicID2, addr2, nic2Dst) - - // Enabling NIC1 should make routes to odd addresses available again. Routes - // to even addresses should continue to be unavailable as NIC2 is still - // disabled. - if err := s.EnableNIC(nicID1); err != nil { - t.Fatalf("s.EnableNIC(%d): %s", nicID1, err) - } - testRoute(t, s, unspecifiedNIC, "", nic1Dst, addr1) - testRoute(t, s, unspecifiedNIC, addr1, nic1Dst, addr1) - testRoute(t, s, nicID1, addr1, nic1Dst, addr1) - testNoRoute(t, s, unspecifiedNIC, "", nic2Dst) - testNoRoute(t, s, unspecifiedNIC, addr2, nic2Dst) - testNoRoute(t, s, nicID2, addr2, nic2Dst) -} - -func TestRouteWritePacketWithDisabledNIC(t *testing.T) { const unspecifiedNIC = 0 const nicID1 = 1 const nicID2 = 2 + const addr1 = tcpip.Address("\x01") + const addr2 = tcpip.Address("\x02") + const nic1Dst = tcpip.Address("\x05") + const nic2Dst = tcpip.Address("\x06") + + setup := func(t *testing.T) (*stack.Stack, *channel.Endpoint, *channel.Endpoint) { + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) - s := stack.New(stack.Options{ - NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, - }) + ep1 := channel.New(1, defaultMTU, "") + if err := s.CreateNIC(nicID1, ep1); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID1, err) + } - ep1 := channel.New(1, defaultMTU, "") - if err := s.CreateNIC(nicID1, ep1); err != nil { - t.Fatalf("CreateNIC(%d, _): %s", nicID1, err) - } + if err := s.AddAddress(nicID1, fakeNetNumber, addr1); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID1, fakeNetNumber, addr1, err) + } - addr1 := tcpip.Address("\x01") - if err := s.AddAddress(nicID1, fakeNetNumber, addr1); err != nil { - t.Fatalf("AddAddress(%d, %d, %s): %s", nicID1, fakeNetNumber, addr1, err) - } + ep2 := channel.New(1, defaultMTU, "") + if err := s.CreateNIC(nicID2, ep2); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID2, err) + } - ep2 := channel.New(1, defaultMTU, "") - if err := s.CreateNIC(nicID2, ep2); err != nil { - t.Fatalf("CreateNIC(%d, _): %s", nicID2, err) - } + if err := s.AddAddress(nicID2, fakeNetNumber, addr2); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID2, fakeNetNumber, addr2, err) + } - addr2 := tcpip.Address("\x02") - if err := s.AddAddress(nicID2, fakeNetNumber, addr2); err != nil { - t.Fatalf("AddAddress(%d, %d, %s): %s", nicID2, fakeNetNumber, addr2, err) + // Set a route table that sends all packets with odd destination + // addresses through the first NIC, and all even destination address + // through the second one. + { + subnet0, err := tcpip.NewSubnet("\x00", "\x01") + if err != nil { + t.Fatal(err) + } + subnet1, err := tcpip.NewSubnet("\x01", "\x01") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{ + {Destination: subnet1, Gateway: "\x00", NIC: nicID1}, + {Destination: subnet0, Gateway: "\x00", NIC: nicID2}, + }) + } + + return s, ep1, ep2 } - // Set a route table that sends all packets with odd destination - // addresses through the first NIC, and all even destination address - // through the second one. - { - subnet0, err := tcpip.NewSubnet("\x00", "\x01") - if err != nil { - t.Fatal(err) - } - subnet1, err := tcpip.NewSubnet("\x01", "\x01") - if err != nil { - t.Fatal(err) + // Tests that routes through a down NIC are not used when looking up a route + // for a destination. + t.Run("Find", func(t *testing.T) { + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + s, _, _ := setup(t) + + // Test routes to odd address. + testRoute(t, s, unspecifiedNIC, "", "\x05", addr1) + testRoute(t, s, unspecifiedNIC, addr1, "\x05", addr1) + testRoute(t, s, nicID1, addr1, "\x05", addr1) + + // Test routes to even address. + testRoute(t, s, unspecifiedNIC, "", "\x06", addr2) + testRoute(t, s, unspecifiedNIC, addr2, "\x06", addr2) + testRoute(t, s, nicID2, addr2, "\x06", addr2) + + // Bringing NIC1 down should result in no routes to odd addresses. Routes to + // even addresses should continue to be available as NIC2 is still up. + if err := test.downFn(s, nicID1); err != nil { + t.Fatalf("test.downFn(_, %d): %s", nicID1, err) + } + testNoRoute(t, s, unspecifiedNIC, "", nic1Dst) + testNoRoute(t, s, unspecifiedNIC, addr1, nic1Dst) + testNoRoute(t, s, nicID1, addr1, nic1Dst) + testRoute(t, s, unspecifiedNIC, "", nic2Dst, addr2) + testRoute(t, s, unspecifiedNIC, addr2, nic2Dst, addr2) + testRoute(t, s, nicID2, addr2, nic2Dst, addr2) + + // Bringing NIC2 down should result in no routes to even addresses. No + // route should be available to any address as routes to odd addresses + // were made unavailable by bringing NIC1 down above. + if err := test.downFn(s, nicID2); err != nil { + t.Fatalf("test.downFn(_, %d): %s", nicID2, err) + } + testNoRoute(t, s, unspecifiedNIC, "", nic1Dst) + testNoRoute(t, s, unspecifiedNIC, addr1, nic1Dst) + testNoRoute(t, s, nicID1, addr1, nic1Dst) + testNoRoute(t, s, unspecifiedNIC, "", nic2Dst) + testNoRoute(t, s, unspecifiedNIC, addr2, nic2Dst) + testNoRoute(t, s, nicID2, addr2, nic2Dst) + + if upFn := test.upFn; upFn != nil { + // Bringing NIC1 up should make routes to odd addresses available + // again. Routes to even addresses should continue to be unavailable + // as NIC2 is still down. + if err := upFn(s, nicID1); err != nil { + t.Fatalf("test.upFn(_, %d): %s", nicID1, err) + } + testRoute(t, s, unspecifiedNIC, "", nic1Dst, addr1) + testRoute(t, s, unspecifiedNIC, addr1, nic1Dst, addr1) + testRoute(t, s, nicID1, addr1, nic1Dst, addr1) + testNoRoute(t, s, unspecifiedNIC, "", nic2Dst) + testNoRoute(t, s, unspecifiedNIC, addr2, nic2Dst) + testNoRoute(t, s, nicID2, addr2, nic2Dst) + } + }) } - s.SetRouteTable([]tcpip.Route{ - {Destination: subnet1, Gateway: "\x00", NIC: nicID1}, - {Destination: subnet0, Gateway: "\x00", NIC: nicID2}, - }) - } + }) - nic1Dst := tcpip.Address("\x05") - r1, err := s.FindRoute(nicID1, addr1, nic1Dst, fakeNetNumber, false /* multicastLoop */) - if err != nil { - t.Errorf("FindRoute(%d, %s, %s, %d, false): %s", nicID1, addr1, nic1Dst, fakeNetNumber, err) - } - defer r1.Release() + // Tests that writing a packet using a Route through a down NIC fails. + t.Run("WritePacket", func(t *testing.T) { + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + s, ep1, ep2 := setup(t) - nic2Dst := tcpip.Address("\x06") - r2, err := s.FindRoute(nicID2, addr2, nic2Dst, fakeNetNumber, false /* multicastLoop */) - if err != nil { - t.Errorf("FindRoute(%d, %s, %s, %d, false): %s", nicID2, addr2, nic2Dst, fakeNetNumber, err) - } - defer r2.Release() + r1, err := s.FindRoute(nicID1, addr1, nic1Dst, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Errorf("FindRoute(%d, %s, %s, %d, false): %s", nicID1, addr1, nic1Dst, fakeNetNumber, err) + } + defer r1.Release() - // If we failed to get routes r1 or r2, we cannot proceed with the test. - if t.Failed() { - t.FailNow() - } + r2, err := s.FindRoute(nicID2, addr2, nic2Dst, fakeNetNumber, false /* multicastLoop */) + if err != nil { + t.Errorf("FindRoute(%d, %s, %s, %d, false): %s", nicID2, addr2, nic2Dst, fakeNetNumber, err) + } + defer r2.Release() - buf := buffer.View([]byte{1}) - testSend(t, r1, ep1, buf) - testSend(t, r2, ep2, buf) + // If we failed to get routes r1 or r2, we cannot proceed with the test. + if t.Failed() { + t.FailNow() + } - // Writes with Routes that use the disabled NIC1 should fail. - if err := s.DisableNIC(nicID1); err != nil { - t.Fatalf("s.DisableNIC(%d): %s", nicID1, err) - } - testFailingSend(t, r1, ep1, buf, tcpip.ErrInvalidEndpointState) - testSend(t, r2, ep2, buf) + buf := buffer.View([]byte{1}) + testSend(t, r1, ep1, buf) + testSend(t, r2, ep2, buf) - // Writes with Routes that use the disabled NIC2 should fail. - if err := s.DisableNIC(nicID2); err != nil { - t.Fatalf("s.DisableNIC(%d): %s", nicID2, err) - } - testFailingSend(t, r1, ep1, buf, tcpip.ErrInvalidEndpointState) - testFailingSend(t, r2, ep2, buf, tcpip.ErrInvalidEndpointState) + // Writes with Routes that use NIC1 after being brought down should fail. + if err := test.downFn(s, nicID1); err != nil { + t.Fatalf("test.downFn(_, %d): %s", nicID1, err) + } + testFailingSend(t, r1, ep1, buf, tcpip.ErrInvalidEndpointState) + testSend(t, r2, ep2, buf) - // Writes with Routes that use the re-enabled NIC1 should succeed. - // TODO(b/147015577): Should we instead completely invalidate all Routes that - // were bound to a disabled NIC at some point? - if err := s.EnableNIC(nicID1); err != nil { - t.Fatalf("s.EnableNIC(%d): %s", nicID1, err) - } - testSend(t, r1, ep1, buf) - testFailingSend(t, r2, ep2, buf, tcpip.ErrInvalidEndpointState) + // Writes with Routes that use NIC2 after being brought down should fail. + if err := test.downFn(s, nicID2); err != nil { + t.Fatalf("test.downFn(_, %d): %s", nicID2, err) + } + testFailingSend(t, r1, ep1, buf, tcpip.ErrInvalidEndpointState) + testFailingSend(t, r2, ep2, buf, tcpip.ErrInvalidEndpointState) + + if upFn := test.upFn; upFn != nil { + // Writes with Routes that use NIC1 after being brought up should + // succeed. + // + // TODO(b/147015577): Should we instead completely invalidate all + // Routes that were bound to a NIC that was brought down at some + // point? + if err := upFn(s, nicID1); err != nil { + t.Fatalf("test.upFn(_, %d): %s", nicID1, err) + } + testSend(t, r1, ep1, buf) + testFailingSend(t, r2, ep2, buf, tcpip.ErrInvalidEndpointState) + } + }) + } + }) } func TestRoutes(t *testing.T) { @@ -2213,7 +2257,7 @@ func TestNICStats(t *testing.T) { // Send a packet to address 1. buf := buffer.NewView(30) - ep1.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + ep1.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if got, want := s.NICInfo()[1].Stats.Rx.Packets.Value(), uint64(1); got != want { @@ -2240,56 +2284,84 @@ func TestNICStats(t *testing.T) { } func TestNICForwarding(t *testing.T) { - // Create a stack with the fake network protocol, two NICs, each with - // an address. - s := stack.New(stack.Options{ - NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, - }) - s.SetForwarding(true) + const nicID1 = 1 + const nicID2 = 2 + const dstAddr = tcpip.Address("\x03") - ep1 := channel.New(10, defaultMTU, "") - if err := s.CreateNIC(1, ep1); err != nil { - t.Fatal("CreateNIC #1 failed:", err) - } - if err := s.AddAddress(1, fakeNetNumber, "\x01"); err != nil { - t.Fatal("AddAddress #1 failed:", err) + tests := []struct { + name string + headerLen uint16 + }{ + { + name: "Zero header length", + }, + { + name: "Non-zero header length", + headerLen: 16, + }, } - ep2 := channel.New(10, defaultMTU, "") - if err := s.CreateNIC(2, ep2); err != nil { - t.Fatal("CreateNIC #2 failed:", err) - } - if err := s.AddAddress(2, fakeNetNumber, "\x02"); err != nil { - t.Fatal("AddAddress #2 failed:", err) - } + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + s.SetForwarding(true) - // Route all packets to address 3 to NIC 2. - { - subnet, err := tcpip.NewSubnet("\x03", "\xff") - if err != nil { - t.Fatal(err) - } - s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: 2}}) - } + ep1 := channel.New(10, defaultMTU, "") + if err := s.CreateNIC(nicID1, ep1); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID1, err) + } + if err := s.AddAddress(nicID1, fakeNetNumber, "\x01"); err != nil { + t.Fatalf("AddAddress(%d, %d, 0x01): %s", nicID1, fakeNetNumber, err) + } - // Send a packet to address 3. - buf := buffer.NewView(30) - buf[0] = 3 - ep1.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ - Data: buf.ToVectorisedView(), - }) + ep2 := channelLinkWithHeaderLength{ + Endpoint: channel.New(10, defaultMTU, ""), + headerLength: test.headerLen, + } + if err := s.CreateNIC(nicID2, &ep2); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID2, err) + } + if err := s.AddAddress(nicID2, fakeNetNumber, "\x02"); err != nil { + t.Fatalf("AddAddress(%d, %d, 0x02): %s", nicID2, fakeNetNumber, err) + } - if _, ok := ep2.Read(); !ok { - t.Fatal("Packet not forwarded") - } + // Route all packets to dstAddr to NIC 2. + { + subnet, err := tcpip.NewSubnet(dstAddr, "\xff") + if err != nil { + t.Fatal(err) + } + s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: nicID2}}) + } - // Test that forwarding increments Tx stats correctly. - if got, want := s.NICInfo()[2].Stats.Tx.Packets.Value(), uint64(1); got != want { - t.Errorf("got Tx.Packets.Value() = %d, want = %d", got, want) - } + // Send a packet to dstAddr. + buf := buffer.NewView(30) + buf[0] = dstAddr[0] + ep1.InjectInbound(fakeNetNumber, stack.PacketBuffer{ + Data: buf.ToVectorisedView(), + }) - if got, want := s.NICInfo()[2].Stats.Tx.Bytes.Value(), uint64(len(buf)); got != want { - t.Errorf("got Tx.Bytes.Value() = %d, want = %d", got, want) + pkt, ok := ep2.Read() + if !ok { + t.Fatal("packet not forwarded") + } + + // Test that the link's MaxHeaderLength is honoured. + if capacity, want := pkt.Pkt.Header.AvailableLength(), int(test.headerLen); capacity != want { + t.Errorf("got Header.AvailableLength() = %d, want = %d", capacity, want) + } + + // Test that forwarding increments Tx stats correctly. + if got, want := s.NICInfo()[nicID2].Stats.Tx.Packets.Value(), uint64(1); got != want { + t.Errorf("got Tx.Packets.Value() = %d, want = %d", got, want) + } + + if got, want := s.NICInfo()[nicID2].Stats.Tx.Bytes.Value(), uint64(len(buf)); got != want { + t.Errorf("got Tx.Bytes.Value() = %d, want = %d", got, want) + } + }) } } @@ -3010,6 +3082,50 @@ func TestAddRemoveIPv4BroadcastAddressOnNICEnableDisable(t *testing.T) { } } +// TestLeaveIPv6SolicitedNodeAddrBeforeAddrRemoval tests that removing an IPv6 +// address after leaving its solicited node multicast address does not result in +// an error. +func TestLeaveIPv6SolicitedNodeAddrBeforeAddrRemoval(t *testing.T) { + const nicID = 1 + + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + }) + e := channel.New(10, 1280, linkAddr1) + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(%d, _): %s", nicID, err) + } + + if err := s.AddAddress(nicID, ipv6.ProtocolNumber, addr1); err != nil { + t.Fatalf("AddAddress(%d, %d, %s): %s", nicID, ipv6.ProtocolNumber, addr1, err) + } + + // The NIC should have joined addr1's solicited node multicast address. + snmc := header.SolicitedNodeAddr(addr1) + in, err := s.IsInGroup(nicID, snmc) + if err != nil { + t.Fatalf("IsInGroup(%d, %s): %s", nicID, snmc, err) + } + if !in { + t.Fatalf("got IsInGroup(%d, %s) = false, want = true", nicID, snmc) + } + + if err := s.LeaveGroup(ipv6.ProtocolNumber, nicID, snmc); err != nil { + t.Fatalf("LeaveGroup(%d, %d, %s): %s", ipv6.ProtocolNumber, nicID, snmc, err) + } + in, err = s.IsInGroup(nicID, snmc) + if err != nil { + t.Fatalf("IsInGroup(%d, %s): %s", nicID, snmc, err) + } + if in { + t.Fatalf("got IsInGroup(%d, %s) = true, want = false", nicID, snmc) + } + + if err := s.RemoveAddress(nicID, addr1); err != nil { + t.Fatalf("RemoveAddress(%d, %s) = %s", nicID, addr1, err) + } +} + func TestJoinLeaveAllNodesMulticastOnNICEnableDisable(t *testing.T) { const nicID = 1 diff --git a/pkg/tcpip/stack/transport_demuxer.go b/pkg/tcpip/stack/transport_demuxer.go index 778c0a4d6..c55e3e8bc 100644 --- a/pkg/tcpip/stack/transport_demuxer.go +++ b/pkg/tcpip/stack/transport_demuxer.go @@ -15,9 +15,9 @@ package stack import ( + "container/heap" "fmt" "math/rand" - "sort" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/tcpip" @@ -85,7 +85,7 @@ func (epsByNic *endpointsByNic) transportEndpoints() []TransportEndpoint { // HandlePacket is called by the stack when new packets arrive to this transport // endpoint. -func (epsByNic *endpointsByNic) handlePacket(r *Route, id TransportEndpointID, pkt tcpip.PacketBuffer) { +func (epsByNic *endpointsByNic) handlePacket(r *Route, id TransportEndpointID, pkt PacketBuffer) { epsByNic.mu.RLock() mpep, ok := epsByNic.endpoints[r.ref.nic.ID()] @@ -116,7 +116,7 @@ func (epsByNic *endpointsByNic) handlePacket(r *Route, id TransportEndpointID, p } // HandleControlPacket implements stack.TransportEndpoint.HandleControlPacket. -func (epsByNic *endpointsByNic) handleControlPacket(n *NIC, id TransportEndpointID, typ ControlType, extra uint32, pkt tcpip.PacketBuffer) { +func (epsByNic *endpointsByNic) handleControlPacket(n *NIC, id TransportEndpointID, typ ControlType, extra uint32, pkt PacketBuffer) { epsByNic.mu.RLock() defer epsByNic.mu.RUnlock() @@ -141,16 +141,17 @@ func (epsByNic *endpointsByNic) registerEndpoint(d *transportDemuxer, netProto t epsByNic.mu.Lock() defer epsByNic.mu.Unlock() - if multiPortEp, ok := epsByNic.endpoints[bindToDevice]; ok { - // There was already a bind. - return multiPortEp.singleRegisterEndpoint(t, reusePort) + multiPortEp, ok := epsByNic.endpoints[bindToDevice] + if !ok { + multiPortEp = &multiPortEndpoint{ + demux: d, + netProto: netProto, + transProto: transProto, + reuse: reusePort, + } + epsByNic.endpoints[bindToDevice] = multiPortEp } - // This is a new binding. - multiPortEp := &multiPortEndpoint{demux: d, netProto: netProto, transProto: transProto} - multiPortEp.endpointsMap = make(map[TransportEndpoint]int) - multiPortEp.reuse = reusePort - epsByNic.endpoints[bindToDevice] = multiPortEp return multiPortEp.singleRegisterEndpoint(t, reusePort) } @@ -183,7 +184,7 @@ type transportDemuxer struct { // the dispatcher to delivery packets to the QueuePacket method instead of // calling HandlePacket directly on the endpoint. type queuedTransportProtocol interface { - QueuePacket(r *Route, ep TransportEndpoint, id TransportEndpointID, pkt tcpip.PacketBuffer) + QueuePacket(r *Route, ep TransportEndpoint, id TransportEndpointID, pkt PacketBuffer) } func newTransportDemuxer(stack *Stack) *transportDemuxer { @@ -222,6 +223,35 @@ func (d *transportDemuxer) registerEndpoint(netProtos []tcpip.NetworkProtocolNum return nil } +type transportEndpointHeap []TransportEndpoint + +var _ heap.Interface = (*transportEndpointHeap)(nil) + +func (h *transportEndpointHeap) Len() int { + return len(*h) +} + +func (h *transportEndpointHeap) Less(i, j int) bool { + return (*h)[i].UniqueID() < (*h)[j].UniqueID() +} + +func (h *transportEndpointHeap) Swap(i, j int) { + (*h)[i], (*h)[j] = (*h)[j], (*h)[i] +} + +func (h *transportEndpointHeap) Push(x interface{}) { + *h = append(*h, x.(TransportEndpoint)) +} + +func (h *transportEndpointHeap) Pop() interface{} { + old := *h + n := len(old) + x := old[n-1] + old[n-1] = nil + *h = old[:n-1] + return x +} + // multiPortEndpoint is a container for TransportEndpoints which are bound to // the same pair of address and port. endpointsArr always has at least one // element. @@ -237,15 +267,14 @@ type multiPortEndpoint struct { netProto tcpip.NetworkProtocolNumber transProto tcpip.TransportProtocolNumber - endpointsArr []TransportEndpoint - endpointsMap map[TransportEndpoint]int + endpoints transportEndpointHeap // reuse indicates if more than one endpoint is allowed. reuse bool } func (ep *multiPortEndpoint) transportEndpoints() []TransportEndpoint { ep.mu.RLock() - eps := append([]TransportEndpoint(nil), ep.endpointsArr...) + eps := append([]TransportEndpoint(nil), ep.endpoints...) ep.mu.RUnlock() return eps } @@ -262,8 +291,8 @@ func reciprocalScale(val, n uint32) uint32 { // ports then uses it to select a socket. In this case, all packets from one // address will be sent to same endpoint. func selectEndpoint(id TransportEndpointID, mpep *multiPortEndpoint, seed uint32) TransportEndpoint { - if len(mpep.endpointsArr) == 1 { - return mpep.endpointsArr[0] + if len(mpep.endpoints) == 1 { + return mpep.endpoints[0] } payload := []byte{ @@ -279,29 +308,26 @@ func selectEndpoint(id TransportEndpointID, mpep *multiPortEndpoint, seed uint32 h.Write([]byte(id.RemoteAddress)) hash := h.Sum32() - idx := reciprocalScale(hash, uint32(len(mpep.endpointsArr))) - return mpep.endpointsArr[idx] + idx := reciprocalScale(hash, uint32(len(mpep.endpoints))) + return mpep.endpoints[idx] } -func (ep *multiPortEndpoint) handlePacketAll(r *Route, id TransportEndpointID, pkt tcpip.PacketBuffer) { +func (ep *multiPortEndpoint) handlePacketAll(r *Route, id TransportEndpointID, pkt PacketBuffer) { ep.mu.RLock() queuedProtocol, mustQueue := ep.demux.queuedProtocols[protocolIDs{ep.netProto, ep.transProto}] - for i, endpoint := range ep.endpointsArr { - // HandlePacket takes ownership of pkt, so each endpoint needs - // its own copy except for the final one. - if i == len(ep.endpointsArr)-1 { - if mustQueue { - queuedProtocol.QueuePacket(r, endpoint, id, pkt) - break - } - endpoint.HandlePacket(r, id, pkt) - break - } + // HandlePacket takes ownership of pkt, so each endpoint needs + // its own copy except for the final one. + for _, endpoint := range ep.endpoints[:len(ep.endpoints)-1] { if mustQueue { queuedProtocol.QueuePacket(r, endpoint, id, pkt.Clone()) - continue + } else { + endpoint.HandlePacket(r, id, pkt.Clone()) } - endpoint.HandlePacket(r, id, pkt.Clone()) + } + if endpoint := ep.endpoints[len(ep.endpoints)-1]; mustQueue { + queuedProtocol.QueuePacket(r, endpoint, id, pkt) + } else { + endpoint.HandlePacket(r, id, pkt) } ep.mu.RUnlock() // Don't use defer for performance reasons. } @@ -312,26 +338,15 @@ func (ep *multiPortEndpoint) singleRegisterEndpoint(t TransportEndpoint, reusePo ep.mu.Lock() defer ep.mu.Unlock() - if len(ep.endpointsArr) > 0 { + if len(ep.endpoints) != 0 { // If it was previously bound, we need to check if we can bind again. if !ep.reuse || !reusePort { return tcpip.ErrPortInUse } } - // A new endpoint is added into endpointsArr and its index there is saved in - // endpointsMap. This will allow us to remove endpoint from the array fast. - ep.endpointsMap[t] = len(ep.endpointsArr) - ep.endpointsArr = append(ep.endpointsArr, t) + heap.Push(&ep.endpoints, t) - // ep.endpointsArr is sorted by endpoint unique IDs, so that endpoints - // can be restored in the same order. - sort.Slice(ep.endpointsArr, func(i, j int) bool { - return ep.endpointsArr[i].UniqueID() < ep.endpointsArr[j].UniqueID() - }) - for i, e := range ep.endpointsArr { - ep.endpointsMap[e] = i - } return nil } @@ -340,21 +355,13 @@ func (ep *multiPortEndpoint) unregisterEndpoint(t TransportEndpoint) bool { ep.mu.Lock() defer ep.mu.Unlock() - idx, ok := ep.endpointsMap[t] - if !ok { - return false - } - delete(ep.endpointsMap, t) - l := len(ep.endpointsArr) - if l > 1 { - // The last endpoint in endpointsArr is moved instead of the deleted one. - lastEp := ep.endpointsArr[l-1] - ep.endpointsArr[idx] = lastEp - ep.endpointsMap[lastEp] = idx - ep.endpointsArr = ep.endpointsArr[0 : l-1] - return false + for i, endpoint := range ep.endpoints { + if endpoint == t { + heap.Remove(&ep.endpoints, i) + break + } } - return true + return len(ep.endpoints) == 0 } func (d *transportDemuxer) singleRegisterEndpoint(netProto tcpip.NetworkProtocolNumber, protocol tcpip.TransportProtocolNumber, id TransportEndpointID, ep TransportEndpoint, reusePort bool, bindToDevice tcpip.NICID) *tcpip.Error { @@ -371,17 +378,14 @@ func (d *transportDemuxer) singleRegisterEndpoint(netProto tcpip.NetworkProtocol eps.mu.Lock() defer eps.mu.Unlock() - if epsByNic, ok := eps.endpoints[id]; ok { - // There was already a binding. - return epsByNic.registerEndpoint(d, netProto, protocol, ep, reusePort, bindToDevice) - } - - // This is a new binding. - epsByNic := &endpointsByNic{ - endpoints: make(map[tcpip.NICID]*multiPortEndpoint), - seed: rand.Uint32(), + epsByNic, ok := eps.endpoints[id] + if !ok { + epsByNic = &endpointsByNic{ + endpoints: make(map[tcpip.NICID]*multiPortEndpoint), + seed: rand.Uint32(), + } + eps.endpoints[id] = epsByNic } - eps.endpoints[id] = epsByNic return epsByNic.registerEndpoint(d, netProto, protocol, ep, reusePort, bindToDevice) } @@ -396,84 +400,60 @@ func (d *transportDemuxer) unregisterEndpoint(netProtos []tcpip.NetworkProtocolN } } -var loopbackSubnet = func() tcpip.Subnet { - sn, err := tcpip.NewSubnet("\x7f\x00\x00\x00", "\xff\x00\x00\x00") - if err != nil { - panic(err) - } - return sn -}() - // deliverPacket attempts to find one or more matching transport endpoints, and // then, if matches are found, delivers the packet to them. Returns true if // the packet no longer needs to be handled. -func (d *transportDemuxer) deliverPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt tcpip.PacketBuffer, id TransportEndpointID) bool { +func (d *transportDemuxer) deliverPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt PacketBuffer, id TransportEndpointID) bool { eps, ok := d.protocol[protocolIDs{r.NetProto, protocol}] if !ok { return false } - eps.mu.RLock() - - // Determine which transport endpoint or endpoints to deliver this packet to. // If the packet is a UDP broadcast or multicast, then find all matching - // transport endpoints. If the packet is a TCP packet with a non-unicast - // source or destination address, then do nothing further and instruct - // the caller to do the same. - var destEps []*endpointsByNic - switch protocol { - case header.UDPProtocolNumber: - if isMulticastOrBroadcast(id.LocalAddress) { - destEps = d.findAllEndpointsLocked(eps, id) - break - } - - if ep := d.findEndpointLocked(eps, id); ep != nil { - destEps = append(destEps, ep) + // transport endpoints. + if protocol == header.UDPProtocolNumber && isMulticastOrBroadcast(id.LocalAddress) { + eps.mu.RLock() + destEPs := d.findAllEndpointsLocked(eps, id) + eps.mu.RUnlock() + // Fail if we didn't find at least one matching transport endpoint. + if len(destEPs) == 0 { + r.Stats().UDP.UnknownPortErrors.Increment() + return false } - - case header.TCPProtocolNumber: - if !(isUnicast(r.LocalAddress) && isUnicast(r.RemoteAddress)) { - // TCP can only be used to communicate between a single - // source and a single destination; the addresses must - // be unicast. - eps.mu.RUnlock() - r.Stats().TCP.InvalidSegmentsReceived.Increment() - return true + // handlePacket takes ownership of pkt, so each endpoint needs its own + // copy except for the final one. + for _, ep := range destEPs[:len(destEPs)-1] { + ep.handlePacket(r, id, pkt.Clone()) } + destEPs[len(destEPs)-1].handlePacket(r, id, pkt) + return true + } - fallthrough - - default: - if ep := d.findEndpointLocked(eps, id); ep != nil { - destEps = append(destEps, ep) - } + // If the packet is a TCP packet with a non-unicast source or destination + // address, then do nothing further and instruct the caller to do the same. + if protocol == header.TCPProtocolNumber && (!isUnicast(r.LocalAddress) || !isUnicast(r.RemoteAddress)) { + // TCP can only be used to communicate between a single source and a + // single destination; the addresses must be unicast. + r.Stats().TCP.InvalidSegmentsReceived.Increment() + return true } + eps.mu.RLock() + ep := d.findEndpointLocked(eps, id) eps.mu.RUnlock() - - // Fail if we didn't find at least one matching transport endpoint. - if len(destEps) == 0 { - // UDP packet could not be delivered to an unknown destination port. + if ep == nil { if protocol == header.UDPProtocolNumber { r.Stats().UDP.UnknownPortErrors.Increment() } return false } - - // HandlePacket takes ownership of pkt, so each endpoint needs its own - // copy except for the final one. - for _, ep := range destEps[:len(destEps)-1] { - ep.handlePacket(r, id, pkt.Clone()) - } - destEps[len(destEps)-1].handlePacket(r, id, pkt) - + ep.handlePacket(r, id, pkt) return true } // deliverRawPacket attempts to deliver the given packet and returns whether it // was delivered successfully. -func (d *transportDemuxer) deliverRawPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt tcpip.PacketBuffer) bool { +func (d *transportDemuxer) deliverRawPacket(r *Route, protocol tcpip.TransportProtocolNumber, pkt PacketBuffer) bool { eps, ok := d.protocol[protocolIDs{r.NetProto, protocol}] if !ok { return false @@ -497,7 +477,7 @@ func (d *transportDemuxer) deliverRawPacket(r *Route, protocol tcpip.TransportPr // deliverControlPacket attempts to deliver the given control packet. Returns // true if it found an endpoint, false otherwise. -func (d *transportDemuxer) deliverControlPacket(n *NIC, net tcpip.NetworkProtocolNumber, trans tcpip.TransportProtocolNumber, typ ControlType, extra uint32, pkt tcpip.PacketBuffer, id TransportEndpointID) bool { +func (d *transportDemuxer) deliverControlPacket(n *NIC, net tcpip.NetworkProtocolNumber, trans tcpip.TransportProtocolNumber, typ ControlType, extra uint32, pkt PacketBuffer, id TransportEndpointID) bool { eps, ok := d.protocol[protocolIDs{net, trans}] if !ok { return false @@ -519,11 +499,17 @@ func (d *transportDemuxer) deliverControlPacket(n *NIC, net tcpip.NetworkProtoco return true } -func (d *transportDemuxer) findAllEndpointsLocked(eps *transportEndpoints, id TransportEndpointID) []*endpointsByNic { - var matchedEPs []*endpointsByNic +// iterEndpointsLocked yields all endpointsByNic in eps that match id, in +// descending order of match quality. If a call to yield returns false, +// iterEndpointsLocked stops iteration and returns immediately. +// +// Preconditions: eps.mu must be locked. +func (d *transportDemuxer) iterEndpointsLocked(eps *transportEndpoints, id TransportEndpointID, yield func(*endpointsByNic) bool) { // Try to find a match with the id as provided. if ep, ok := eps.endpoints[id]; ok { - matchedEPs = append(matchedEPs, ep) + if !yield(ep) { + return + } } // Try to find a match with the id minus the local address. @@ -531,7 +517,9 @@ func (d *transportDemuxer) findAllEndpointsLocked(eps *transportEndpoints, id Tr nid.LocalAddress = "" if ep, ok := eps.endpoints[nid]; ok { - matchedEPs = append(matchedEPs, ep) + if !yield(ep) { + return + } } // Try to find a match with the id minus the remote part. @@ -539,14 +527,26 @@ func (d *transportDemuxer) findAllEndpointsLocked(eps *transportEndpoints, id Tr nid.RemoteAddress = "" nid.RemotePort = 0 if ep, ok := eps.endpoints[nid]; ok { - matchedEPs = append(matchedEPs, ep) + if !yield(ep) { + return + } } // Try to find a match with only the local port. nid.LocalAddress = "" if ep, ok := eps.endpoints[nid]; ok { - matchedEPs = append(matchedEPs, ep) + if !yield(ep) { + return + } } +} + +func (d *transportDemuxer) findAllEndpointsLocked(eps *transportEndpoints, id TransportEndpointID) []*endpointsByNic { + var matchedEPs []*endpointsByNic + d.iterEndpointsLocked(eps, id, func(ep *endpointsByNic) bool { + matchedEPs = append(matchedEPs, ep) + return true + }) return matchedEPs } @@ -584,10 +584,12 @@ func (d *transportDemuxer) findTransportEndpoint(netProto tcpip.NetworkProtocolN // findEndpointLocked returns the endpoint that most closely matches the given // id. func (d *transportDemuxer) findEndpointLocked(eps *transportEndpoints, id TransportEndpointID) *endpointsByNic { - if matchedEPs := d.findAllEndpointsLocked(eps, id); len(matchedEPs) > 0 { - return matchedEPs[0] - } - return nil + var matchedEP *endpointsByNic + d.iterEndpointsLocked(eps, id, func(ep *endpointsByNic) bool { + matchedEP = ep + return false + }) + return matchedEP } // registerRawEndpoint registers the given endpoint with the dispatcher such @@ -601,8 +603,8 @@ func (d *transportDemuxer) registerRawEndpoint(netProto tcpip.NetworkProtocolNum } eps.mu.Lock() - defer eps.mu.Unlock() eps.rawEndpoints = append(eps.rawEndpoints, ep) + eps.mu.Unlock() return nil } @@ -616,13 +618,16 @@ func (d *transportDemuxer) unregisterRawEndpoint(netProto tcpip.NetworkProtocolN } eps.mu.Lock() - defer eps.mu.Unlock() for i, rawEP := range eps.rawEndpoints { if rawEP == ep { - eps.rawEndpoints = append(eps.rawEndpoints[:i], eps.rawEndpoints[i+1:]...) - return + lastIdx := len(eps.rawEndpoints) - 1 + eps.rawEndpoints[i] = eps.rawEndpoints[lastIdx] + eps.rawEndpoints[lastIdx] = nil + eps.rawEndpoints = eps.rawEndpoints[:lastIdx] + break } } + eps.mu.Unlock() } func isMulticastOrBroadcast(addr tcpip.Address) bool { diff --git a/pkg/tcpip/stack/transport_demuxer_test.go b/pkg/tcpip/stack/transport_demuxer_test.go index 5e9237de9..84311bcc8 100644 --- a/pkg/tcpip/stack/transport_demuxer_test.go +++ b/pkg/tcpip/stack/transport_demuxer_test.go @@ -150,7 +150,7 @@ func (c *testContext) sendV6Packet(payload []byte, h *headers, linkEpID tcpip.NI u.SetChecksum(^u.CalculateChecksum(xsum)) // Inject packet. - c.linkEps[linkEpID].InjectInbound(ipv6.ProtocolNumber, tcpip.PacketBuffer{ + c.linkEps[linkEpID].InjectInbound(ipv6.ProtocolNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) } @@ -167,8 +167,18 @@ func TestTransportDemuxerRegister(t *testing.T) { t.Run(test.name, func(t *testing.T) { s := stack.New(stack.Options{ NetworkProtocols: []stack.NetworkProtocol{ipv4.NewProtocol()}, - TransportProtocols: []stack.TransportProtocol{udp.NewProtocol()}}) - if got, want := s.RegisterTransportEndpoint(0, []tcpip.NetworkProtocolNumber{test.proto}, udp.ProtocolNumber, stack.TransportEndpointID{}, nil, false, 0), test.want; got != want { + TransportProtocols: []stack.TransportProtocol{udp.NewProtocol()}, + }) + var wq waiter.Queue + ep, err := s.NewEndpoint(udp.ProtocolNumber, ipv4.ProtocolNumber, &wq) + if err != nil { + t.Fatal(err) + } + tEP, ok := ep.(stack.TransportEndpoint) + if !ok { + t.Fatalf("%T does not implement stack.TransportEndpoint", ep) + } + if got, want := s.RegisterTransportEndpoint(0, []tcpip.NetworkProtocolNumber{test.proto}, udp.ProtocolNumber, stack.TransportEndpointID{}, tEP, false, 0), test.want; got != want { t.Fatalf("s.RegisterTransportEndpoint(...) = %v, want %v", got, want) } }) diff --git a/pkg/tcpip/stack/transport_test.go b/pkg/tcpip/stack/transport_test.go index 5d1da2f8b..8ca9ac3cf 100644 --- a/pkg/tcpip/stack/transport_test.go +++ b/pkg/tcpip/stack/transport_test.go @@ -19,7 +19,6 @@ import ( "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" - "gvisor.dev/gvisor/pkg/tcpip/iptables" "gvisor.dev/gvisor/pkg/tcpip/link/channel" "gvisor.dev/gvisor/pkg/tcpip/link/loopback" "gvisor.dev/gvisor/pkg/tcpip/stack" @@ -87,7 +86,7 @@ func (f *fakeTransportEndpoint) Write(p tcpip.Payloader, opts tcpip.WriteOptions if err != nil { return 0, nil, err } - if err := f.route.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: fakeTransNumber, TTL: 123, TOS: stack.DefaultTOS}, tcpip.PacketBuffer{ + if err := f.route.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: fakeTransNumber, TTL: 123, TOS: stack.DefaultTOS}, stack.PacketBuffer{ Header: hdr, Data: buffer.View(v).ToVectorisedView(), }); err != nil { @@ -214,7 +213,7 @@ func (*fakeTransportEndpoint) GetRemoteAddress() (tcpip.FullAddress, *tcpip.Erro return tcpip.FullAddress{}, nil } -func (f *fakeTransportEndpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, _ tcpip.PacketBuffer) { +func (f *fakeTransportEndpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, _ stack.PacketBuffer) { // Increment the number of received packets. f.proto.packetCount++ if f.acceptQueue != nil { @@ -231,7 +230,7 @@ func (f *fakeTransportEndpoint) HandlePacket(r *stack.Route, id stack.TransportE } } -func (f *fakeTransportEndpoint) HandleControlPacket(stack.TransportEndpointID, stack.ControlType, uint32, tcpip.PacketBuffer) { +func (f *fakeTransportEndpoint) HandleControlPacket(stack.TransportEndpointID, stack.ControlType, uint32, stack.PacketBuffer) { // Increment the number of received control packets. f.proto.controlCount++ } @@ -242,8 +241,8 @@ func (f *fakeTransportEndpoint) State() uint32 { func (f *fakeTransportEndpoint) ModerateRecvBuf(copied int) {} -func (f *fakeTransportEndpoint) IPTables() (iptables.IPTables, error) { - return iptables.IPTables{}, nil +func (f *fakeTransportEndpoint) IPTables() (stack.IPTables, error) { + return stack.IPTables{}, nil } func (f *fakeTransportEndpoint) Resume(*stack.Stack) {} @@ -288,7 +287,7 @@ func (*fakeTransportProtocol) ParsePorts(buffer.View) (src, dst uint16, err *tcp return 0, 0, nil } -func (*fakeTransportProtocol) HandleUnknownDestinationPacket(*stack.Route, stack.TransportEndpointID, tcpip.PacketBuffer) bool { +func (*fakeTransportProtocol) HandleUnknownDestinationPacket(*stack.Route, stack.TransportEndpointID, stack.PacketBuffer) bool { return true } @@ -368,7 +367,7 @@ func TestTransportReceive(t *testing.T) { // Make sure packet with wrong protocol is not delivered. buf[0] = 1 buf[2] = 0 - linkEP.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + linkEP.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeTrans.packetCount != 0 { @@ -379,7 +378,7 @@ func TestTransportReceive(t *testing.T) { buf[0] = 1 buf[1] = 3 buf[2] = byte(fakeTransNumber) - linkEP.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + linkEP.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeTrans.packetCount != 0 { @@ -390,7 +389,7 @@ func TestTransportReceive(t *testing.T) { buf[0] = 1 buf[1] = 2 buf[2] = byte(fakeTransNumber) - linkEP.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + linkEP.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeTrans.packetCount != 1 { @@ -445,7 +444,7 @@ func TestTransportControlReceive(t *testing.T) { buf[fakeNetHeaderLen+0] = 0 buf[fakeNetHeaderLen+1] = 1 buf[fakeNetHeaderLen+2] = 0 - linkEP.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + linkEP.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeTrans.controlCount != 0 { @@ -456,7 +455,7 @@ func TestTransportControlReceive(t *testing.T) { buf[fakeNetHeaderLen+0] = 3 buf[fakeNetHeaderLen+1] = 1 buf[fakeNetHeaderLen+2] = byte(fakeTransNumber) - linkEP.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + linkEP.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeTrans.controlCount != 0 { @@ -467,7 +466,7 @@ func TestTransportControlReceive(t *testing.T) { buf[fakeNetHeaderLen+0] = 2 buf[fakeNetHeaderLen+1] = 1 buf[fakeNetHeaderLen+2] = byte(fakeTransNumber) - linkEP.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + linkEP.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: buf.ToVectorisedView(), }) if fakeTrans.controlCount != 1 { @@ -622,7 +621,7 @@ func TestTransportForwarding(t *testing.T) { req[0] = 1 req[1] = 3 req[2] = byte(fakeTransNumber) - ep2.InjectInbound(fakeNetNumber, tcpip.PacketBuffer{ + ep2.InjectInbound(fakeNetNumber, stack.PacketBuffer{ Data: req.ToVectorisedView(), }) |