diff options
Diffstat (limited to 'pkg/tcpip/stack')
-rw-r--r-- | pkg/tcpip/stack/BUILD | 1 | ||||
-rw-r--r-- | pkg/tcpip/stack/ndp_test.go | 3 | ||||
-rw-r--r-- | pkg/tcpip/stack/nic.go | 175 | ||||
-rw-r--r-- | pkg/tcpip/stack/registration.go | 83 | ||||
-rw-r--r-- | pkg/tcpip/stack/route.go | 48 | ||||
-rw-r--r-- | pkg/tcpip/stack/stack.go | 178 | ||||
-rw-r--r-- | pkg/tcpip/stack/stack_test.go | 286 | ||||
-rw-r--r-- | pkg/tcpip/stack/transport_demuxer.go | 2 |
8 files changed, 714 insertions, 62 deletions
diff --git a/pkg/tcpip/stack/BUILD b/pkg/tcpip/stack/BUILD index bfc03e90b..460db3cf8 100644 --- a/pkg/tcpip/stack/BUILD +++ b/pkg/tcpip/stack/BUILD @@ -73,6 +73,7 @@ go_test( "//pkg/tcpip/transport/icmp", "//pkg/tcpip/transport/udp", "//pkg/waiter", + "@com_github_google_go-cmp//cmp:go_default_library", ], ) diff --git a/pkg/tcpip/stack/ndp_test.go b/pkg/tcpip/stack/ndp_test.go index 849c2f35f..8995fbfc3 100644 --- a/pkg/tcpip/stack/ndp_test.go +++ b/pkg/tcpip/stack/ndp_test.go @@ -31,8 +31,7 @@ import ( const ( addr1 = "\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01" addr2 = "\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02" - linkAddr1 = "\x01\x02\x03\x04\x05\x06" - linkAddr2 = "\x01\x02\x03\x04\x05\x07" + linkAddr1 = "\x02\x02\x03\x04\x05\x06" ) // TestDADDisabled tests that an address successfully resolves immediately diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 38d066cd1..e456e05f4 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -40,6 +40,9 @@ type NIC struct { endpoints map[NetworkEndpointID]*referencedNetworkEndpoint addressRanges []tcpip.Subnet mcastJoins map[NetworkEndpointID]int32 + // packetEPs is protected by mu, but the contained PacketEndpoint + // values are not. + packetEPs map[tcpip.NetworkProtocolNumber][]PacketEndpoint stats NICStats @@ -78,7 +81,10 @@ const ( ) func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, loopback bool) *NIC { - return &NIC{ + // TODO(b/141011931): Validate a LinkEndpoint (ep) is valid. For + // example, make sure that the link address it provides is a valid + // unicast ethernet address. + nic := &NIC{ stack: stack, id: id, name: name, @@ -87,6 +93,7 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, loopback primary: make(map[tcpip.NetworkProtocolNumber][]*referencedNetworkEndpoint), endpoints: make(map[NetworkEndpointID]*referencedNetworkEndpoint), mcastJoins: make(map[NetworkEndpointID]int32), + packetEPs: make(map[tcpip.NetworkProtocolNumber][]PacketEndpoint), stats: NICStats{ Tx: DirectionStats{ Packets: &tcpip.StatCounter{}, @@ -101,6 +108,16 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, loopback dad: make(map[tcpip.Address]dadState), }, } + + // Register supported packet endpoint protocols. + for _, netProto := range header.Ethertypes { + nic.packetEPs[netProto] = []PacketEndpoint{} + } + for _, netProto := range stack.networkProtocols { + nic.packetEPs[netProto.Number()] = []PacketEndpoint{} + } + + return nic } // enable enables the NIC. enable will attach the link to its LinkEndpoint and @@ -125,11 +142,50 @@ func (n *NIC) enable() *tcpip.Error { // when we perform Duplicate Address Detection, or Router Advertisement // when we do Router Discovery. See RFC 4862, section 5.4.2 and RFC 4861 // section 4.2 for more information. - if _, ok := n.stack.networkProtocols[header.IPv6ProtocolNumber]; ok { - return n.joinGroup(header.IPv6ProtocolNumber, header.IPv6AllNodesMulticastAddress) + // + // Also auto-generate an IPv6 link-local address based on the NIC's + // link address if it is configured to do so. Note, each interface is + // required to have IPv6 link-local unicast address, as per RFC 4291 + // section 2.1. + _, ok := n.stack.networkProtocols[header.IPv6ProtocolNumber] + if !ok { + return nil } - return nil + n.mu.Lock() + defer n.mu.Unlock() + + if err := n.joinGroupLocked(header.IPv6ProtocolNumber, header.IPv6AllNodesMulticastAddress); err != nil { + return err + } + + if !n.stack.autoGenIPv6LinkLocal { + return nil + } + + l2addr := n.linkEP.LinkAddress() + + // Only attempt to generate the link-local address if we have a + // valid MAC address. + // + // TODO(b/141011931): Validate a LinkEndpoint's link address + // (provided by LinkEndpoint.LinkAddress) before reaching this + // point. + if !header.IsValidUnicastEthernetAddress(l2addr) { + return nil + } + + addr := header.LinkLocalAddr(l2addr) + + _, err := n.addPermanentAddressLocked(tcpip.ProtocolAddress{ + Protocol: header.IPv6ProtocolNumber, + AddressWithPrefix: tcpip.AddressWithPrefix{ + Address: addr, + PrefixLen: header.IPv6LinkLocalPrefix.PrefixLen, + }, + }, CanBePrimaryEndpoint) + + return err } // attachLinkEndpoint attaches the NIC to the endpoint, which will enable it @@ -279,9 +335,31 @@ func (n *NIC) addPermanentAddressLocked(protocolAddress tcpip.ProtocolAddress, p // The NIC already have a permanent endpoint with that address. return nil, tcpip.ErrDuplicateAddress case permanentExpired, temporary: - // Promote the endpoint to become permanent. + // Promote the endpoint to become permanent and respect + // the new peb. if ref.tryIncRef() { ref.setKind(permanent) + + refs := n.primary[ref.protocol] + for i, r := range refs { + if r == ref { + switch peb { + case CanBePrimaryEndpoint: + return ref, nil + case FirstPrimaryEndpoint: + if i == 0 { + return ref, nil + } + n.primary[r.protocol] = append(refs[:i], refs[i+1:]...) + case NeverPrimaryEndpoint: + n.primary[r.protocol] = append(refs[:i], refs[i+1:]...) + return ref, nil + } + } + } + + n.insertPrimaryEndpointLocked(ref, peb) + return ref, nil } // tryIncRef failing means the endpoint is scheduled to be removed once @@ -350,12 +428,7 @@ func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb Primar n.endpoints[id] = ref - switch peb { - case CanBePrimaryEndpoint: - n.primary[protocolAddress.Protocol] = append(n.primary[protocolAddress.Protocol], ref) - case FirstPrimaryEndpoint: - n.primary[protocolAddress.Protocol] = append([]*referencedNetworkEndpoint{ref}, n.primary[protocolAddress.Protocol]...) - } + n.insertPrimaryEndpointLocked(ref, peb) // If we are adding a tentative IPv6 address, start DAD. if isIPv6Unicast && kind == permanentTentative { @@ -477,6 +550,19 @@ func (n *NIC) AddressRanges() []tcpip.Subnet { return append(sns, n.addressRanges...) } +// insertPrimaryEndpointLocked adds r to n's primary endpoint list as required +// by peb. +// +// n MUST be locked. +func (n *NIC) insertPrimaryEndpointLocked(r *referencedNetworkEndpoint, peb PrimaryEndpointBehavior) { + switch peb { + case CanBePrimaryEndpoint: + n.primary[r.protocol] = append(n.primary[r.protocol], r) + case FirstPrimaryEndpoint: + n.primary[r.protocol] = append([]*referencedNetworkEndpoint{r}, n.primary[r.protocol]...) + } +} + func (n *NIC) removeEndpointLocked(r *referencedNetworkEndpoint) { id := *r.ep.ID() @@ -494,9 +580,10 @@ func (n *NIC) removeEndpointLocked(r *referencedNetworkEndpoint) { } delete(n.endpoints, id) - for i, ref := range n.primary[r.protocol] { + refs := n.primary[r.protocol] + for i, ref := range refs { if ref == r { - n.primary[r.protocol] = append(n.primary[r.protocol][:i], n.primary[r.protocol][i+1:]...) + n.primary[r.protocol] = append(refs[:i], refs[i+1:]...) break } } @@ -568,6 +655,11 @@ func (n *NIC) joinGroup(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address // exists yet. Otherwise it just increments its count. n MUST be locked before // joinGroupLocked is called. func (n *NIC) joinGroupLocked(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address) *tcpip.Error { + // TODO(b/143102137): When implementing MLD, make sure MLD packets are + // not sent unless a valid link-local address is available for use on n + // as an MLD packet's source address must be a link-local address as + // outlined in RFC 3810 section 5. + id := NetworkEndpointID{addr} joins := n.mcastJoins[id] if joins == 0 { @@ -631,7 +723,7 @@ 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, _ tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, vv buffer.VectorisedView) { +func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, vv buffer.VectorisedView, linkHeader buffer.View) { n.stats.Rx.Packets.Increment() n.stats.Rx.Bytes.IncrementBy(uint64(vv.Size())) @@ -641,6 +733,26 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, _ tcpip.LinkAddr return } + // If no local link layer address is provided, assume it was sent + // directly to this NIC. + if local == "" { + local = n.linkEP.LinkAddress() + } + + // Are any packet sockets listening for this network protocol? + n.mu.RLock() + packetEPs := n.packetEPs[protocol] + // Check whether there are packet sockets listening for every protocol. + // If we received a packet with protocol EthernetProtocolAll, then the + // previous for loop will have handled it. + if protocol != header.EthernetProtocolAll { + packetEPs = append(packetEPs, n.packetEPs[header.EthernetProtocolAll]...) + } + n.mu.RUnlock() + for _, ep := range packetEPs { + ep.HandlePacket(n.id, local, protocol, vv, linkHeader) + } + if netProto.Number() == header.IPv4ProtocolNumber || netProto.Number() == header.IPv6ProtocolNumber { n.stack.stats.IP.PacketsReceived.Increment() } @@ -700,7 +812,10 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, _ tcpip.LinkAddr return } - n.stack.stats.IP.InvalidAddressesReceived.Increment() + // If a packet socket handled the packet, don't treat it as invalid. + if len(packetEPs) == 0 { + n.stack.stats.IP.InvalidAddressesReceived.Increment() + } } // DeliverTransportPacket delivers the packets to the appropriate transport @@ -856,6 +971,36 @@ const ( temporary ) +func (n *NIC) registerPacketEndpoint(netProto tcpip.NetworkProtocolNumber, ep PacketEndpoint) *tcpip.Error { + n.mu.Lock() + defer n.mu.Unlock() + + eps, ok := n.packetEPs[netProto] + if !ok { + return tcpip.ErrNotSupported + } + n.packetEPs[netProto] = append(eps, ep) + + return nil +} + +func (n *NIC) unregisterPacketEndpoint(netProto tcpip.NetworkProtocolNumber, ep PacketEndpoint) { + n.mu.Lock() + defer n.mu.Unlock() + + eps, ok := n.packetEPs[netProto] + if !ok { + return + } + + for i, epOther := range eps { + if epOther == ep { + n.packetEPs[netProto] = append(eps[:i], eps[i+1:]...) + return + } + } +} + type referencedNetworkEndpoint struct { ep NetworkEndpoint nic *NIC diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go index 9d6157f22..0869fb084 100644 --- a/pkg/tcpip/stack/registration.go +++ b/pkg/tcpip/stack/registration.go @@ -71,8 +71,8 @@ type TransportEndpoint interface { // RawTransportEndpoint is the interface that needs to be implemented by raw // transport protocol endpoints. RawTransportEndpoints receive the entire -// packet - including the link, network, and transport headers - as delivered -// to netstack. +// packet - including the network and transport headers - as delivered to +// netstack. type RawTransportEndpoint interface { // HandlePacket is called by the stack when new packets arrive to // this transport endpoint. The packet contains all data from the link @@ -80,6 +80,22 @@ type RawTransportEndpoint interface { HandlePacket(r *Route, netHeader buffer.View, packet buffer.VectorisedView) } +// PacketEndpoint is the interface that needs to be implemented by packet +// transport protocol endpoints. These endpoints receive link layer headers in +// addition to whatever they contain (usually network and transport layer +// headers and a payload). +type PacketEndpoint interface { + // HandlePacket is called by the stack when new packets arrive that + // match the endpoint. + // + // Implementers should treat packet as immutable and should copy it + // before before modification. + // + // linkHeader may have a length of 0, in which case the PacketEndpoint + // should construct its own ethernet header for applications. + HandlePacket(nicid tcpip.NICID, addr tcpip.LinkAddress, netProto tcpip.NetworkProtocolNumber, packet buffer.VectorisedView, linkHeader buffer.View) +} + // TransportProtocol is the interface that needs to be implemented by transport // protocols (e.g., tcp, udp) that want to be part of the networking stack. type TransportProtocol interface { @@ -185,6 +201,10 @@ type NetworkEndpoint interface { // protocol. WritePacket(r *Route, gso *GSO, hdr buffer.Prependable, payload buffer.VectorisedView, params NetworkHeaderParams, loop PacketLooping) *tcpip.Error + // WritePackets writes packets to the given destination address and + // protocol. + WritePackets(r *Route, gso *GSO, hdrs []PacketDescriptor, payload buffer.VectorisedView, params NetworkHeaderParams, loop PacketLooping) (int, *tcpip.Error) + // WriteHeaderIncludedPacket writes a packet that includes a network // header to the given destination address. WriteHeaderIncludedPacket(r *Route, payload buffer.VectorisedView, loop PacketLooping) *tcpip.Error @@ -242,9 +262,10 @@ type NetworkProtocol interface { // packets to the appropriate network endpoint after it has been handled by // the data link layer. type NetworkDispatcher interface { - // DeliverNetworkPacket finds the appropriate network protocol - // endpoint and hands the packet over for further processing. - DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, vv buffer.VectorisedView) + // DeliverNetworkPacket finds the appropriate network protocol endpoint + // and hands the packet over for further processing. linkHeader may have + // length 0 when the caller does not have ethernet data. + DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, vv buffer.VectorisedView, linkHeader buffer.View) } // LinkEndpointCapabilities is the type associated with the capabilities @@ -266,7 +287,11 @@ const ( CapabilitySaveRestore CapabilityDisconnectOk CapabilityLoopback - CapabilityGSO + CapabilityHardwareGSO + + // CapabilitySoftwareGSO indicates the link endpoint supports of sending + // multiple packets using a single call (LinkEndpoint.WritePackets). + CapabilitySoftwareGSO ) // LinkEndpoint is the interface implemented by data link layer protocols (e.g., @@ -301,6 +326,18 @@ type LinkEndpoint interface { // r.LocalLinkAddress if it is provided. WritePacket(r *Route, gso *GSO, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) *tcpip.Error + // WritePackets writes packets with the given protocol through the + // given route. + // + // 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, hdrs []PacketDescriptor, payload buffer.VectorisedView, protocol tcpip.NetworkProtocolNumber) (int, *tcpip.Error) + + // WriteRawPacket writes a packet directly to the link. The packet + // should already have an ethernet header. + WriteRawPacket(packet buffer.VectorisedView) *tcpip.Error + // Attach attaches the data link layer endpoint to the network-layer // dispatcher of the stack. Attach(dispatcher NetworkDispatcher) @@ -324,13 +361,14 @@ type LinkEndpoint interface { type InjectableLinkEndpoint interface { LinkEndpoint - // Inject injects an inbound packet. - Inject(protocol tcpip.NetworkProtocolNumber, vv buffer.VectorisedView) + // InjectInbound injects an inbound packet. + InjectInbound(protocol tcpip.NetworkProtocolNumber, vv buffer.VectorisedView) - // WriteRawPacket writes a fully formed outbound packet directly to the link. + // InjectOutbound writes a fully formed outbound packet directly to the + // link. // // dest is used by endpoints with multiple raw destinations. - WriteRawPacket(dest tcpip.Address, packet []byte) *tcpip.Error + InjectOutbound(dest tcpip.Address, packet []byte) *tcpip.Error } // A LinkAddressResolver is an extension to a NetworkProtocol that @@ -379,11 +417,16 @@ type LinkAddressCache interface { RemoveWaker(nicid tcpip.NICID, addr tcpip.Address, waker *sleep.Waker) } -// UnassociatedEndpointFactory produces endpoints for writing packets not -// associated with a particular transport protocol. Such endpoints can be used -// to write arbitrary packets that include the IP header. -type UnassociatedEndpointFactory interface { - NewUnassociatedRawEndpoint(stack *Stack, netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) +// RawFactory produces endpoints for writing various types of raw packets. +type RawFactory interface { + // NewUnassociatedEndpoint produces endpoints for writing packets not + // associated with a particular transport protocol. Such endpoints can + // be used to write arbitrary packets that include the network header. + NewUnassociatedEndpoint(stack *Stack, netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) + + // NewPacketEndpoint produces endpoints for reading and writing packets + // that include network and (when cooked is false) link layer headers. + NewPacketEndpoint(stack *Stack, cooked bool, netProto tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) } // GSOType is the type of GSO segments. @@ -394,8 +437,14 @@ type GSOType int // Types of gso segments. const ( GSONone GSOType = iota + + // Hardware GSO types: GSOTCPv4 GSOTCPv6 + + // GSOSW is used for software GSO segments which have to be sent by + // endpoint.WritePackets. + GSOSW ) // GSO contains generic segmentation offload properties. @@ -423,3 +472,7 @@ type GSOEndpoint interface { // GSOMaxSize returns the maximum GSO packet size. GSOMaxSize() uint32 } + +// SoftwareGSOMaxSize is a maximum allowed size of a software GSO segment. +// This isn't a hard limit, because it is never set into packet headers. +const SoftwareGSOMaxSize = (1 << 16) diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go index e72373964..1a0a51b57 100644 --- a/pkg/tcpip/stack/route.go +++ b/pkg/tcpip/stack/route.go @@ -47,8 +47,8 @@ type Route struct { // starts. ref *referencedNetworkEndpoint - // loop controls where WritePacket should send packets. - loop PacketLooping + // Loop controls where WritePacket should send packets. + Loop PacketLooping } // makeRoute initializes a new route. It takes ownership of the provided @@ -69,7 +69,7 @@ func makeRoute(netProto tcpip.NetworkProtocolNumber, localAddr, remoteAddr tcpip LocalLinkAddress: localLinkAddr, RemoteAddress: remoteAddr, ref: ref, - loop: loop, + Loop: loop, } } @@ -159,7 +159,7 @@ func (r *Route) WritePacket(gso *GSO, hdr buffer.Prependable, payload buffer.Vec return tcpip.ErrInvalidEndpointState } - err := r.ref.ep.WritePacket(r, gso, hdr, payload, params, r.loop) + err := r.ref.ep.WritePacket(r, gso, hdr, payload, params, r.Loop) if err != nil { r.Stats().IP.OutgoingPacketErrors.Increment() } else { @@ -169,6 +169,44 @@ func (r *Route) WritePacket(gso *GSO, hdr buffer.Prependable, payload buffer.Vec return err } +// PacketDescriptor is a packet descriptor which contains a packet header and +// offset and size of packet data in a payload view. +type PacketDescriptor struct { + Hdr buffer.Prependable + Off int + Size int +} + +// NewPacketDescriptors allocates a set of packet descriptors. +func NewPacketDescriptors(n int, hdrSize int) []PacketDescriptor { + buf := make([]byte, n*hdrSize) + hdrs := make([]PacketDescriptor, n) + for i := range hdrs { + hdrs[i].Hdr = buffer.NewEmptyPrependableFromView(buf[i*hdrSize:][:hdrSize]) + } + return hdrs +} + +// WritePackets writes the set of packets through the given route. +func (r *Route) WritePackets(gso *GSO, hdrs []PacketDescriptor, payload buffer.VectorisedView, params NetworkHeaderParams) (int, *tcpip.Error) { + if !r.ref.isValidForOutgoing() { + return 0, tcpip.ErrInvalidEndpointState + } + + n, err := r.ref.ep.WritePackets(r, gso, hdrs, payload, params, r.Loop) + if err != nil { + r.Stats().IP.OutgoingPacketErrors.IncrementBy(uint64(len(hdrs) - n)) + } + r.ref.nic.stats.Tx.Packets.IncrementBy(uint64(n)) + payloadSize := 0 + for i := 0; i < n; i++ { + r.ref.nic.stats.Tx.Bytes.IncrementBy(uint64(hdrs[i].Hdr.UsedLength())) + payloadSize += hdrs[i].Size + } + r.ref.nic.stats.Tx.Bytes.IncrementBy(uint64(payloadSize)) + return n, err +} + // WriteHeaderIncludedPacket writes a packet already containing a network // header through the given route. func (r *Route) WriteHeaderIncludedPacket(payload buffer.VectorisedView) *tcpip.Error { @@ -176,7 +214,7 @@ func (r *Route) WriteHeaderIncludedPacket(payload buffer.VectorisedView) *tcpip. return tcpip.ErrInvalidEndpointState } - if err := r.ref.ep.WriteHeaderIncludedPacket(r, payload, r.loop); err != nil { + if err := r.ref.ep.WriteHeaderIncludedPacket(r, payload, r.Loop); err != nil { r.Stats().IP.OutgoingPacketErrors.Increment() return err } diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index a199bc1cc..284280917 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -351,10 +351,9 @@ type Stack struct { networkProtocols map[tcpip.NetworkProtocolNumber]NetworkProtocol linkAddrResolvers map[tcpip.NetworkProtocolNumber]LinkAddressResolver - // unassociatedFactory creates unassociated endpoints. If nil, raw - // endpoints are disabled. It is set during Stack creation and is - // immutable. - unassociatedFactory UnassociatedEndpointFactory + // rawFactory creates raw endpoints. If nil, raw endpoints are + // disabled. It is set during Stack creation and is immutable. + rawFactory RawFactory demux *transportDemuxer @@ -402,6 +401,11 @@ type Stack struct { // ndpConfigs is the NDP configurations used by interfaces. ndpConfigs NDPConfigurations + + // autoGenIPv6LinkLocal determines whether or not the stack will attempt + // to auto-generate an IPv6 link-local address for newly enabled NICs. + // See the AutoGenIPv6LinkLocal field of Options for more details. + autoGenIPv6LinkLocal bool } // Options contains optional Stack configuration. @@ -425,16 +429,28 @@ type Options struct { // stack (false). HandleLocal bool - // UnassociatedFactory produces unassociated endpoints raw endpoints. - // Raw endpoints are enabled only if this is non-nil. - UnassociatedFactory UnassociatedEndpointFactory - // NDPConfigs is the NDP configurations used by interfaces. // // By default, NDPConfigs will have a zero value for its // DupAddrDetectTransmits field, implying that DAD will not be performed // before assigning an address to a NIC. NDPConfigs NDPConfigurations + + // AutoGenIPv6LinkLocal determins whether or not the stack will attempt + // to auto-generate an IPv6 link-local address for newly enabled NICs. + // Note, setting this to true does not mean that a link-local address + // will be assigned right away, or at all. If Duplicate Address + // Detection is enabled, an address will only be assigned if it + // successfully resolves. If it fails, no further attempt will be made + // to auto-generate an IPv6 link-local address. + // + // The generated link-local address will follow RFC 4291 Appendix A + // guidelines. + AutoGenIPv6LinkLocal bool + + // RawFactory produces raw endpoints. Raw endpoints are enabled only if + // this is non-nil. + RawFactory RawFactory } // TransportEndpointInfo holds useful information about a transport endpoint @@ -485,18 +501,19 @@ func New(opts Options) *Stack { opts.NDPConfigs.validate() s := &Stack{ - transportProtocols: make(map[tcpip.TransportProtocolNumber]*transportProtocolState), - networkProtocols: make(map[tcpip.NetworkProtocolNumber]NetworkProtocol), - linkAddrResolvers: make(map[tcpip.NetworkProtocolNumber]LinkAddressResolver), - nics: make(map[tcpip.NICID]*NIC), - linkAddrCache: newLinkAddrCache(ageLimit, resolutionTimeout, resolutionAttempts), - PortManager: ports.NewPortManager(), - clock: clock, - stats: opts.Stats.FillIn(), - handleLocal: opts.HandleLocal, - icmpRateLimiter: NewICMPRateLimiter(), - portSeed: generateRandUint32(), - ndpConfigs: opts.NDPConfigs, + transportProtocols: make(map[tcpip.TransportProtocolNumber]*transportProtocolState), + networkProtocols: make(map[tcpip.NetworkProtocolNumber]NetworkProtocol), + linkAddrResolvers: make(map[tcpip.NetworkProtocolNumber]LinkAddressResolver), + nics: make(map[tcpip.NICID]*NIC), + linkAddrCache: newLinkAddrCache(ageLimit, resolutionTimeout, resolutionAttempts), + PortManager: ports.NewPortManager(), + clock: clock, + stats: opts.Stats.FillIn(), + handleLocal: opts.HandleLocal, + icmpRateLimiter: NewICMPRateLimiter(), + portSeed: generateRandUint32(), + ndpConfigs: opts.NDPConfigs, + autoGenIPv6LinkLocal: opts.AutoGenIPv6LinkLocal, } // Add specified network protocols. @@ -514,8 +531,8 @@ func New(opts Options) *Stack { } } - // Add the factory for unassociated endpoints, if present. - s.unassociatedFactory = opts.UnassociatedFactory + // Add the factory for raw endpoints, if present. + s.rawFactory = opts.RawFactory // Create the global transport demuxer. s.demux = newTransportDemuxer(s) @@ -650,12 +667,12 @@ func (s *Stack) NewEndpoint(transport tcpip.TransportProtocolNumber, network tcp // protocol. Raw endpoints receive all traffic for a given protocol regardless // of address. func (s *Stack) NewRawEndpoint(transport tcpip.TransportProtocolNumber, network tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue, associated bool) (tcpip.Endpoint, *tcpip.Error) { - if s.unassociatedFactory == nil { + if s.rawFactory == nil { return nil, tcpip.ErrNotPermitted } if !associated { - return s.unassociatedFactory.NewUnassociatedRawEndpoint(s, network, transport, waiterQueue) + return s.rawFactory.NewUnassociatedEndpoint(s, network, transport, waiterQueue) } t, ok := s.transportProtocols[transport] @@ -666,6 +683,16 @@ func (s *Stack) NewRawEndpoint(transport tcpip.TransportProtocolNumber, network return t.proto.NewRawEndpoint(s, network, waiterQueue) } +// NewPacketEndpoint creates a new packet endpoint listening for the given +// netProto. +func (s *Stack) NewPacketEndpoint(cooked bool, netProto tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { + if s.rawFactory == nil { + return nil, tcpip.ErrNotPermitted + } + + return s.rawFactory.NewPacketEndpoint(s, cooked, netProto, waiterQueue) +} + // createNIC creates a NIC with the provided id and link-layer endpoint, and // optionally enable it. func (s *Stack) createNIC(id tcpip.NICID, name string, ep LinkEndpoint, enabled, loopback bool) *tcpip.Error { @@ -1135,6 +1162,109 @@ func (s *Stack) Resume() { } } +// RegisterPacketEndpoint registers ep with the stack, causing it to receive +// all traffic of the specified netProto on the given NIC. If nicID is 0, it +// receives traffic from every NIC. +func (s *Stack) RegisterPacketEndpoint(nicID tcpip.NICID, netProto tcpip.NetworkProtocolNumber, ep PacketEndpoint) *tcpip.Error { + s.mu.Lock() + defer s.mu.Unlock() + + // If no NIC is specified, capture on all devices. + if nicID == 0 { + // Register with each NIC. + for _, nic := range s.nics { + if err := nic.registerPacketEndpoint(netProto, ep); err != nil { + s.unregisterPacketEndpointLocked(0, netProto, ep) + return err + } + } + return nil + } + + // Capture on a specific device. + nic, ok := s.nics[nicID] + if !ok { + return tcpip.ErrUnknownNICID + } + if err := nic.registerPacketEndpoint(netProto, ep); err != nil { + return err + } + + return nil +} + +// UnregisterPacketEndpoint unregisters ep for packets of the specified +// netProto from the specified NIC. If nicID is 0, ep is unregistered from all +// NICs. +func (s *Stack) UnregisterPacketEndpoint(nicID tcpip.NICID, netProto tcpip.NetworkProtocolNumber, ep PacketEndpoint) { + s.mu.Lock() + defer s.mu.Unlock() + s.unregisterPacketEndpointLocked(nicID, netProto, ep) +} + +func (s *Stack) unregisterPacketEndpointLocked(nicID tcpip.NICID, netProto tcpip.NetworkProtocolNumber, ep PacketEndpoint) { + // If no NIC is specified, unregister on all devices. + if nicID == 0 { + // Unregister with each NIC. + for _, nic := range s.nics { + nic.unregisterPacketEndpoint(netProto, ep) + } + return + } + + // Unregister in a single device. + nic, ok := s.nics[nicID] + if !ok { + return + } + nic.unregisterPacketEndpoint(netProto, ep) +} + +// WritePacket writes data directly to the specified NIC. It adds an ethernet +// header based on the arguments. +func (s *Stack) WritePacket(nicid tcpip.NICID, dst tcpip.LinkAddress, netProto tcpip.NetworkProtocolNumber, payload buffer.VectorisedView) *tcpip.Error { + s.mu.Lock() + nic, ok := s.nics[nicid] + s.mu.Unlock() + if !ok { + return tcpip.ErrUnknownDevice + } + + // Add our own fake ethernet header. + ethFields := header.EthernetFields{ + SrcAddr: nic.linkEP.LinkAddress(), + DstAddr: dst, + Type: netProto, + } + fakeHeader := make(header.Ethernet, header.EthernetMinimumSize) + fakeHeader.Encode(ðFields) + ethHeader := buffer.View(fakeHeader).ToVectorisedView() + ethHeader.Append(payload) + + if err := nic.linkEP.WriteRawPacket(ethHeader); err != nil { + return err + } + + return nil +} + +// WriteRawPacket writes data directly to the specified NIC without adding any +// headers. +func (s *Stack) WriteRawPacket(nicid tcpip.NICID, payload buffer.VectorisedView) *tcpip.Error { + s.mu.Lock() + nic, ok := s.nics[nicid] + s.mu.Unlock() + if !ok { + return tcpip.ErrUnknownDevice + } + + if err := nic.linkEP.WriteRawPacket(payload); err != nil { + return err + } + + return nil +} + // NetworkProtocolInstance returns the protocol instance in the stack for the // specified network protocol. This method is public for protocol implementers // and tests to use. diff --git a/pkg/tcpip/stack/stack_test.go b/pkg/tcpip/stack/stack_test.go index 10fd1065f..9a8906a0d 100644 --- a/pkg/tcpip/stack/stack_test.go +++ b/pkg/tcpip/stack/stack_test.go @@ -24,11 +24,14 @@ import ( "sort" "strings" "testing" + "time" + "github.com/google/go-cmp/cmp" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/link/channel" + "gvisor.dev/gvisor/pkg/tcpip/network/ipv6" "gvisor.dev/gvisor/pkg/tcpip/stack" ) @@ -144,6 +147,11 @@ func (f *fakeNetworkEndpoint) WritePacket(r *stack.Route, gso *stack.GSO, hdr bu return f.ep.WritePacket(r, gso, hdr, payload, fakeNetNumber) } +// WritePackets implements stack.LinkEndpoint.WritePackets. +func (f *fakeNetworkEndpoint) WritePackets(r *stack.Route, gso *stack.GSO, hdrs []stack.PacketDescriptor, payload buffer.VectorisedView, params stack.NetworkHeaderParams, loop stack.PacketLooping) (int, *tcpip.Error) { + panic("not implemented") +} + func (*fakeNetworkEndpoint) WriteHeaderIncludedPacket(r *stack.Route, payload buffer.VectorisedView, loop stack.PacketLooping) *tcpip.Error { return tcpip.ErrNotSupported } @@ -1864,3 +1872,281 @@ func TestNICForwarding(t *testing.T) { t.Errorf("got Tx.Bytes.Value() = %d, want = %d", got, want) } } + +// TestNICAutoGenAddr tests the auto-generation of IPv6 link-local addresses +// (or lack there-of if disabled (default)). Note, DAD will be disabled in +// these tests. +func TestNICAutoGenAddr(t *testing.T) { + tests := []struct { + name string + autoGen bool + linkAddr tcpip.LinkAddress + shouldGen bool + }{ + { + "Disabled", + false, + linkAddr1, + false, + }, + { + "Enabled", + true, + linkAddr1, + true, + }, + { + "Nil MAC", + true, + tcpip.LinkAddress([]byte(nil)), + false, + }, + { + "Empty MAC", + true, + tcpip.LinkAddress(""), + false, + }, + { + "Invalid MAC", + true, + tcpip.LinkAddress("\x01\x02\x03"), + false, + }, + { + "Multicast MAC", + true, + tcpip.LinkAddress("\x01\x02\x03\x04\x05\x06"), + false, + }, + { + "Unspecified MAC", + true, + tcpip.LinkAddress("\x00\x00\x00\x00\x00\x00"), + false, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + opts := stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + } + + if test.autoGen { + // Only set opts.AutoGenIPv6LinkLocal when + // test.autoGen is true because + // opts.AutoGenIPv6LinkLocal should be false by + // default. + opts.AutoGenIPv6LinkLocal = true + } + + e := channel.New(10, 1280, test.linkAddr) + s := stack.New(opts) + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(_) = %s", err) + } + + addr, err := s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("stack.GetMainNICAddress(_, _) err = %s", err) + } + + if test.shouldGen { + // Should have auto-generated an address and + // resolved immediately (DAD is disabled). + if want := (tcpip.AddressWithPrefix{Address: header.LinkLocalAddr(test.linkAddr), PrefixLen: header.IPv6LinkLocalPrefix.PrefixLen}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = %s, want = %s", addr, want) + } + } else { + // Should not have auto-generated an address. + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + } + }) + } +} + +// TestNICAutoGenAddrDoesDAD tests that the successful auto-generation of IPv6 +// link-local addresses will only be assigned after the DAD process resolves. +func TestNICAutoGenAddrDoesDAD(t *testing.T) { + opts := stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{ipv6.NewProtocol()}, + NDPConfigs: stack.NDPConfigurations{ + RetransmitTimer: time.Second, + DupAddrDetectTransmits: 1, + }, + AutoGenIPv6LinkLocal: true, + } + + e := channel.New(10, 1280, linkAddr1) + s := stack.New(opts) + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(_) = %s", err) + } + + // Address should not be considered bound to the + // NIC yet (DAD ongoing). + addr, err := s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (_, %v), want = (_, nil)", err) + } + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = (%s, nil), want = (%s, nil)", addr, want) + } + + // Wait for the address to resolve (an extra + // 250ms to make sure the address resolves). + // + // TODO(b/140896005): Use events from the + // netstack to know immediately when DAD + // completes. + time.Sleep(time.Second + 250*time.Millisecond) + + // Should have auto-generated an address and + // resolved (if DAD). + addr, err = s.GetMainNICAddress(1, header.IPv6ProtocolNumber) + if err != nil { + t.Fatalf("stack.GetMainNICAddress(_, _) err = %s", err) + } + if want := (tcpip.AddressWithPrefix{Address: header.LinkLocalAddr(linkAddr1), PrefixLen: header.IPv6LinkLocalPrefix.PrefixLen}); addr != want { + t.Fatalf("got stack.GetMainNICAddress(_, _) = %s, want = %s", addr, want) + } +} + +// TestNewPEB tests that a new PrimaryEndpointBehavior value (peb) is respected +// when an address's kind gets "promoted" to permanent from permanentExpired. +func TestNewPEBOnPromotionToPermanent(t *testing.T) { + pebs := []stack.PrimaryEndpointBehavior{ + stack.NeverPrimaryEndpoint, + stack.CanBePrimaryEndpoint, + stack.FirstPrimaryEndpoint, + } + + for _, pi := range pebs { + for _, ps := range pebs { + t.Run(fmt.Sprintf("%d-to-%d", pi, ps), func(t *testing.T) { + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{fakeNetFactory()}, + }) + ep1 := channel.New(10, defaultMTU, "") + if err := s.CreateNIC(1, ep1); err != nil { + t.Fatal("CreateNIC failed:", err) + } + + // Add a permanent address with initial + // PrimaryEndpointBehavior (peb), pi. If pi is + // NeverPrimaryEndpoint, the address should not + // be returned by a call to GetMainNICAddress; + // else, it should. + if err := s.AddAddressWithOptions(1, fakeNetNumber, "\x01", pi); err != nil { + t.Fatal("AddAddressWithOptions failed:", err) + } + addr, err := s.GetMainNICAddress(1, fakeNetNumber) + if err != nil { + t.Fatal("s.GetMainNICAddress failed:", err) + } + if pi == stack.NeverPrimaryEndpoint { + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got GetMainNICAddress = %s, want = %s", addr, want) + + } + } else if addr.Address != "\x01" { + t.Fatalf("got GetMainNICAddress = %s, want = 1", addr.Address) + } + + { + subnet, err := tcpip.NewSubnet("\x00", "\x00") + if err != nil { + t.Fatalf("NewSubnet failed:", err) + } + s.SetRouteTable([]tcpip.Route{{Destination: subnet, Gateway: "\x00", NIC: 1}}) + } + + // Take a route through the address so its ref + // count gets incremented and does not actually + // get deleted when RemoveAddress is called + // below. This is because we want to test that a + // new peb is respected when an address gets + // "promoted" to permanent from a + // permanentExpired kind. + r, err := s.FindRoute(1, "\x01", "\x02", fakeNetNumber, false) + if err != nil { + t.Fatal("FindRoute failed:", err) + } + defer r.Release() + if err := s.RemoveAddress(1, "\x01"); err != nil { + t.Fatalf("RemoveAddress failed:", err) + } + + // + // At this point, the address should still be + // known by the NIC, but have its + // kind = permanentExpired. + // + + // Add some other address with peb set to + // FirstPrimaryEndpoint. + if err := s.AddAddressWithOptions(1, fakeNetNumber, "\x03", stack.FirstPrimaryEndpoint); err != nil { + t.Fatal("AddAddressWithOptions failed:", err) + + } + + // Add back the address we removed earlier and + // make sure the new peb was respected. + // (The address should just be promoted now). + if err := s.AddAddressWithOptions(1, fakeNetNumber, "\x01", ps); err != nil { + t.Fatal("AddAddressWithOptions failed:", err) + } + var primaryAddrs []tcpip.Address + for _, pa := range s.NICInfo()[1].ProtocolAddresses { + primaryAddrs = append(primaryAddrs, pa.AddressWithPrefix.Address) + } + var expectedList []tcpip.Address + switch ps { + case stack.FirstPrimaryEndpoint: + expectedList = []tcpip.Address{ + "\x01", + "\x03", + } + case stack.CanBePrimaryEndpoint: + expectedList = []tcpip.Address{ + "\x03", + "\x01", + } + case stack.NeverPrimaryEndpoint: + expectedList = []tcpip.Address{ + "\x03", + } + } + if !cmp.Equal(primaryAddrs, expectedList) { + t.Fatalf("got NIC's primary addresses = %v, want = %v", primaryAddrs, expectedList) + } + + // Once we remove the other address, if the new + // peb, ps, was NeverPrimaryEndpoint, no address + // should be returned by a call to + // GetMainNICAddress; else, our original address + // should be returned. + if err := s.RemoveAddress(1, "\x03"); err != nil { + t.Fatalf("RemoveAddress failed:", err) + } + addr, err = s.GetMainNICAddress(1, fakeNetNumber) + if err != nil { + t.Fatal("s.GetMainNICAddress failed:", err) + } + if ps == stack.NeverPrimaryEndpoint { + if want := (tcpip.AddressWithPrefix{}); addr != want { + t.Fatalf("got GetMainNICAddress = %s, want = %s", addr, want) + + } + } else { + if addr.Address != "\x01" { + t.Fatalf("got GetMainNICAddress = %s, want = 1", addr.Address) + } + } + }) + } + } +} diff --git a/pkg/tcpip/stack/transport_demuxer.go b/pkg/tcpip/stack/transport_demuxer.go index 92267ce4d..97a1aec4b 100644 --- a/pkg/tcpip/stack/transport_demuxer.go +++ b/pkg/tcpip/stack/transport_demuxer.go @@ -465,7 +465,7 @@ func (d *transportDemuxer) findEndpointLocked(eps *transportEndpoints, vv buffer func (d *transportDemuxer) registerRawEndpoint(netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, ep RawTransportEndpoint) *tcpip.Error { eps, ok := d.protocol[protocolIDs{netProto, transProto}] if !ok { - return nil + return tcpip.ErrNotSupported } eps.mu.Lock() |