diff options
Diffstat (limited to 'pkg/tcpip/transport')
31 files changed, 3868 insertions, 415 deletions
diff --git a/pkg/tcpip/transport/icmp/BUILD b/pkg/tcpip/transport/icmp/BUILD index 9254c3dea..d8c5b5058 100644 --- a/pkg/tcpip/transport/icmp/BUILD +++ b/pkg/tcpip/transport/icmp/BUILD @@ -38,11 +38,3 @@ go_library( "//pkg/waiter", ], ) - -filegroup( - name = "autogen", - srcs = [ - "icmp_packet_list.go", - ], - visibility = ["//:sandbox"], -) diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go index 3187b336b..9c40931b5 100644 --- a/pkg/tcpip/transport/icmp/endpoint.go +++ b/pkg/tcpip/transport/icmp/endpoint.go @@ -31,9 +31,6 @@ type icmpPacket struct { senderAddress tcpip.FullAddress data buffer.VectorisedView `state:".(buffer.VectorisedView)"` timestamp int64 - // views is used as buffer for data when its length is large - // enough to store a VectorisedView. - views [8]buffer.View `state:"nosave"` } type endpointState int @@ -58,6 +55,7 @@ type endpoint struct { // immutable. stack *stack.Stack `state:"manual"` waiterQueue *waiter.Queue + uniqueID uint64 // The following fields are used to manage the receive queue, and are // protected by rcvMu. @@ -90,9 +88,15 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, transProt rcvBufSizeMax: 32 * 1024, sndBufSize: 32 * 1024, state: stateInitial, + uniqueID: s.UniqueID(), }, nil } +// UniqueID implements stack.TransportEndpoint.UniqueID. +func (e *endpoint) UniqueID() uint64 { + return e.uniqueID +} + // Close puts the endpoint in a closed state and frees all resources // associated with it. func (e *endpoint) Close() { @@ -274,13 +278,13 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, <-c } else { // Reject destination address if it goes through a different // NIC than the endpoint was bound to. - nicid := to.NIC + nicID := to.NIC if e.BindNICID != 0 { - if nicid != 0 && nicid != e.BindNICID { + if nicID != 0 && nicID != e.BindNICID { return 0, nil, tcpip.ErrNoRoute } - nicid = e.BindNICID + nicID = e.BindNICID } toCopy := *to @@ -291,7 +295,7 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, <-c } // Find the enpoint. - r, err := e.stack.FindRoute(nicid, e.BindAddr, to.Addr, netProto, false /* multicastLoop */) + r, err := e.stack.FindRoute(nicID, e.BindAddr, to.Addr, netProto, false /* multicastLoop */) if err != nil { return 0, nil, err } @@ -425,7 +429,11 @@ func send4(r *stack.Route, ident uint16, data buffer.View, ttl uint8) *tcpip.Err if ttl == 0 { ttl = r.DefaultTTL() } - return r.WritePacket(nil /* gso */, hdr, data.ToVectorisedView(), stack.NetworkHeaderParams{Protocol: header.ICMPv4ProtocolNumber, TTL: ttl, TOS: stack.DefaultTOS}) + return r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv4ProtocolNumber, TTL: ttl, TOS: stack.DefaultTOS}, tcpip.PacketBuffer{ + Header: hdr, + Data: data.ToVectorisedView(), + TransportHeader: buffer.View(icmpv4), + }) } func send6(r *stack.Route, ident uint16, data buffer.View, ttl uint8) *tcpip.Error { @@ -445,13 +453,17 @@ func send6(r *stack.Route, ident uint16, data buffer.View, ttl uint8) *tcpip.Err return tcpip.ErrInvalidEndpointState } - icmpv6.SetChecksum(0) - icmpv6.SetChecksum(^header.Checksum(icmpv6, header.Checksum(data, 0))) + dataVV := data.ToVectorisedView() + icmpv6.SetChecksum(header.ICMPv6Checksum(icmpv6, r.LocalAddress, r.RemoteAddress, dataVV)) if ttl == 0 { ttl = r.DefaultTTL() } - return r.WritePacket(nil /* gso */, hdr, data.ToVectorisedView(), stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: ttl, TOS: stack.DefaultTOS}) + return r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: ttl, TOS: stack.DefaultTOS}, tcpip.PacketBuffer{ + Header: hdr, + Data: dataVV, + TransportHeader: buffer.View(icmpv6), + }) } func (e *endpoint) checkV4Mapped(addr *tcpip.FullAddress, allowMismatch bool) (tcpip.NetworkProtocolNumber, *tcpip.Error) { @@ -479,7 +491,7 @@ func (e *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { e.mu.Lock() defer e.mu.Unlock() - nicid := addr.NIC + nicID := addr.NIC localPort := uint16(0) switch e.state { case stateBound, stateConnected: @@ -488,11 +500,11 @@ func (e *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { break } - if nicid != 0 && nicid != e.BindNICID { + if nicID != 0 && nicID != e.BindNICID { return tcpip.ErrInvalidEndpointState } - nicid = e.BindNICID + nicID = e.BindNICID default: return tcpip.ErrInvalidEndpointState } @@ -503,7 +515,7 @@ func (e *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { } // Find a route to the desired destination. - r, err := e.stack.FindRoute(nicid, e.BindAddr, addr.Addr, netProto, false /* multicastLoop */) + r, err := e.stack.FindRoute(nicID, e.BindAddr, addr.Addr, netProto, false /* multicastLoop */) if err != nil { return err } @@ -520,14 +532,14 @@ func (e *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { // v6only is set to false and this is an ipv6 endpoint. netProtos := []tcpip.NetworkProtocolNumber{netProto} - id, err = e.registerWithStack(nicid, netProtos, id) + id, err = e.registerWithStack(nicID, netProtos, id) if err != nil { return err } e.ID = id e.route = r.Clone() - e.RegisterNICID = nicid + e.RegisterNICID = nicID e.state = stateConnected @@ -578,18 +590,18 @@ func (*endpoint) Accept() (tcpip.Endpoint, *waiter.Queue, *tcpip.Error) { return nil, nil, tcpip.ErrNotSupported } -func (e *endpoint) registerWithStack(nicid tcpip.NICID, netProtos []tcpip.NetworkProtocolNumber, id stack.TransportEndpointID) (stack.TransportEndpointID, *tcpip.Error) { +func (e *endpoint) registerWithStack(nicID tcpip.NICID, netProtos []tcpip.NetworkProtocolNumber, id stack.TransportEndpointID) (stack.TransportEndpointID, *tcpip.Error) { if id.LocalPort != 0 { // The endpoint already has a local port, just attempt to // register it. - err := e.stack.RegisterTransportEndpoint(nicid, netProtos, e.TransProto, id, e, false /* reuse */, 0 /* bindToDevice */) + err := e.stack.RegisterTransportEndpoint(nicID, netProtos, e.TransProto, id, e, false /* reuse */, 0 /* bindToDevice */) return id, err } // We need to find a port for the endpoint. _, err := e.stack.PickEphemeralPort(func(p uint16) (bool, *tcpip.Error) { id.LocalPort = p - err := e.stack.RegisterTransportEndpoint(nicid, netProtos, e.TransProto, id, e, false /* reuse */, 0 /* bindtodevice */) + err := e.stack.RegisterTransportEndpoint(nicID, netProtos, e.TransProto, id, e, false /* reuse */, 0 /* bindtodevice */) switch err { case nil: return true, nil @@ -714,18 +726,18 @@ func (e *endpoint) Readiness(mask waiter.EventMask) waiter.EventMask { // HandlePacket is called by the stack when new packets arrive to this transport // endpoint. -func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv buffer.VectorisedView) { +func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) { // Only accept echo replies. switch e.NetProto { case header.IPv4ProtocolNumber: - h := header.ICMPv4(vv.First()) + h := header.ICMPv4(pkt.Data.First()) if h.Type() != header.ICMPv4EchoReply { e.stack.Stats().DroppedPackets.Increment() e.stats.ReceiveErrors.MalformedPacketsReceived.Increment() return } case header.IPv6ProtocolNumber: - h := header.ICMPv6(vv.First()) + h := header.ICMPv6(pkt.Data.First()) if h.Type() != header.ICMPv6EchoReply { e.stack.Stats().DroppedPackets.Increment() e.stats.ReceiveErrors.MalformedPacketsReceived.Increment() @@ -753,19 +765,19 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv wasEmpty := e.rcvBufSize == 0 // Push new packet into receive list and increment the buffer size. - pkt := &icmpPacket{ + packet := &icmpPacket{ senderAddress: tcpip.FullAddress{ NIC: r.NICID(), Addr: id.RemoteAddress, }, } - pkt.data = vv.Clone(pkt.views[:]) + packet.data = pkt.Data - e.rcvList.PushBack(pkt) - e.rcvBufSize += pkt.data.Size() + e.rcvList.PushBack(packet) + e.rcvBufSize += packet.data.Size() - pkt.timestamp = e.stack.NowNanoseconds() + packet.timestamp = e.stack.NowNanoseconds() e.rcvMu.Unlock() e.stats.PacketsReceived.Increment() @@ -776,7 +788,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv } // HandleControlPacket implements stack.TransportEndpoint.HandleControlPacket. -func (e *endpoint) HandleControlPacket(id stack.TransportEndpointID, typ stack.ControlType, extra uint32, vv buffer.VectorisedView) { +func (e *endpoint) HandleControlPacket(id stack.TransportEndpointID, typ stack.ControlType, extra uint32, pkt tcpip.PacketBuffer) { } // State implements tcpip.Endpoint.State. The ICMP endpoint currently doesn't @@ -798,3 +810,6 @@ func (e *endpoint) Info() tcpip.EndpointInfo { func (e *endpoint) Stats() tcpip.EndpointStats { return &e.stats } + +// Wait implements stack.TransportEndpoint.Wait. +func (*endpoint) Wait() {} diff --git a/pkg/tcpip/transport/icmp/protocol.go b/pkg/tcpip/transport/icmp/protocol.go index bfb16f7c3..9ce500e80 100644 --- a/pkg/tcpip/transport/icmp/protocol.go +++ b/pkg/tcpip/transport/icmp/protocol.go @@ -104,7 +104,7 @@ func (p *protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) // HandleUnknownDestinationPacket handles packets targeted at this protocol but // that don't match any existing endpoint. -func (p *protocol) HandleUnknownDestinationPacket(*stack.Route, stack.TransportEndpointID, buffer.View, buffer.VectorisedView) bool { +func (p *protocol) HandleUnknownDestinationPacket(*stack.Route, stack.TransportEndpointID, tcpip.PacketBuffer) bool { return true } diff --git a/pkg/tcpip/transport/packet/BUILD b/pkg/tcpip/transport/packet/BUILD new file mode 100644 index 000000000..44b58ff6b --- /dev/null +++ b/pkg/tcpip/transport/packet/BUILD @@ -0,0 +1,38 @@ +load("//tools/go_generics:defs.bzl", "go_template_instance") +load("//tools/go_stateify:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_template_instance( + name = "packet_list", + out = "packet_list.go", + package = "packet", + prefix = "packet", + template = "//pkg/ilist:generic_list", + types = { + "Element": "*packet", + "Linker": "*packet", + }, +) + +go_library( + name = "packet", + srcs = [ + "endpoint.go", + "endpoint_state.go", + "packet_list.go", + ], + importpath = "gvisor.dev/gvisor/pkg/tcpip/transport/packet", + imports = ["gvisor.dev/gvisor/pkg/tcpip/buffer"], + visibility = ["//visibility:public"], + deps = [ + "//pkg/log", + "//pkg/sleep", + "//pkg/tcpip", + "//pkg/tcpip/buffer", + "//pkg/tcpip/header", + "//pkg/tcpip/iptables", + "//pkg/tcpip/stack", + "//pkg/waiter", + ], +) diff --git a/pkg/tcpip/transport/packet/endpoint.go b/pkg/tcpip/transport/packet/endpoint.go new file mode 100644 index 000000000..0010b5e5f --- /dev/null +++ b/pkg/tcpip/transport/packet/endpoint.go @@ -0,0 +1,362 @@ +// 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 packet provides the implementation of packet sockets (see +// packet(7)). Packet sockets allow applications to: +// +// * manually write and inspect link, network, and transport headers +// * receive all traffic of a given network protocol, or all protocols +// +// Packet sockets are similar to raw sockets, but provide even more power to +// users, letting them effectively talk directly to the network device. +// +// Packet sockets skip the input and output iptables chains. +package packet + +import ( + "sync" + + "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/stack" + "gvisor.dev/gvisor/pkg/waiter" +) + +// +stateify savable +type packet struct { + packetEntry + // data holds the actual packet data, including any headers and + // payload. + data buffer.VectorisedView `state:".(buffer.VectorisedView)"` + // timestampNS is the unix time at which the packet was received. + timestampNS int64 + // senderAddr is the network address of the sender. + senderAddr tcpip.FullAddress +} + +// endpoint is the packet socket implementation of tcpip.Endpoint. It is legal +// to have goroutines make concurrent calls into the endpoint. +// +// Lock order: +// endpoint.mu +// endpoint.rcvMu +// +// +stateify savable +type endpoint struct { + stack.TransportEndpointInfo + // The following fields are initialized at creation time and are + // immutable. + stack *stack.Stack `state:"manual"` + netProto tcpip.NetworkProtocolNumber + waiterQueue *waiter.Queue + cooked bool + + // The following fields are used to manage the receive queue and are + // protected by rcvMu. + rcvMu sync.Mutex `state:"nosave"` + rcvList packetList + rcvBufSizeMax int `state:".(int)"` + rcvBufSize int + rcvClosed bool + + // The following fields are protected by mu. + mu sync.RWMutex `state:"nosave"` + sndBufSize int + closed bool + stats tcpip.TransportEndpointStats `state:"nosave"` +} + +// NewEndpoint returns a new packet endpoint. +func NewEndpoint(s *stack.Stack, cooked bool, netProto tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { + ep := &endpoint{ + stack: s, + TransportEndpointInfo: stack.TransportEndpointInfo{ + NetProto: netProto, + }, + cooked: cooked, + netProto: netProto, + waiterQueue: waiterQueue, + rcvBufSizeMax: 32 * 1024, + sndBufSize: 32 * 1024, + } + + if err := s.RegisterPacketEndpoint(0, netProto, ep); err != nil { + return nil, err + } + return ep, nil +} + +// Close implements tcpip.Endpoint.Close. +func (ep *endpoint) Close() { + ep.mu.Lock() + defer ep.mu.Unlock() + + if ep.closed { + return + } + + ep.stack.UnregisterPacketEndpoint(0, ep.netProto, ep) + + ep.rcvMu.Lock() + defer ep.rcvMu.Unlock() + + // Clear the receive list. + ep.rcvClosed = true + ep.rcvBufSize = 0 + for !ep.rcvList.Empty() { + ep.rcvList.Remove(ep.rcvList.Front()) + } + + ep.closed = true + ep.waiterQueue.Notify(waiter.EventHUp | waiter.EventErr | waiter.EventIn | waiter.EventOut) +} + +// ModerateRecvBuf implements tcpip.Endpoint.ModerateRecvBuf. +func (ep *endpoint) ModerateRecvBuf(copied int) {} + +// IPTables implements tcpip.Endpoint.IPTables. +func (ep *endpoint) IPTables() (iptables.IPTables, error) { + return ep.stack.IPTables(), nil +} + +// Read implements tcpip.Endpoint.Read. +func (ep *endpoint) Read(addr *tcpip.FullAddress) (buffer.View, tcpip.ControlMessages, *tcpip.Error) { + ep.rcvMu.Lock() + + // If there's no data to read, return that read would block or that the + // endpoint is closed. + if ep.rcvList.Empty() { + err := tcpip.ErrWouldBlock + if ep.rcvClosed { + ep.stats.ReadErrors.ReadClosed.Increment() + err = tcpip.ErrClosedForReceive + } + ep.rcvMu.Unlock() + return buffer.View{}, tcpip.ControlMessages{}, err + } + + packet := ep.rcvList.Front() + ep.rcvList.Remove(packet) + ep.rcvBufSize -= packet.data.Size() + + ep.rcvMu.Unlock() + + if addr != nil { + *addr = packet.senderAddr + } + + return packet.data.ToView(), tcpip.ControlMessages{HasTimestamp: true, Timestamp: packet.timestampNS}, nil +} + +func (ep *endpoint) Write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, <-chan struct{}, *tcpip.Error) { + // TODO(b/129292371): Implement. + return 0, nil, tcpip.ErrInvalidOptionValue +} + +// Peek implements tcpip.Endpoint.Peek. +func (ep *endpoint) Peek([][]byte) (int64, tcpip.ControlMessages, *tcpip.Error) { + return 0, tcpip.ControlMessages{}, nil +} + +// Disconnect implements tcpip.Endpoint.Disconnect. Packet sockets cannot be +// disconnected, and this function always returns tpcip.ErrNotSupported. +func (*endpoint) Disconnect() *tcpip.Error { + return tcpip.ErrNotSupported +} + +// Connect implements tcpip.Endpoint.Connect. Packet sockets cannot be +// connected, and this function always returnes tcpip.ErrNotSupported. +func (ep *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { + return tcpip.ErrNotSupported +} + +// Shutdown implements tcpip.Endpoint.Shutdown. Packet sockets cannot be used +// with Shutdown, and this function always returns tcpip.ErrNotSupported. +func (ep *endpoint) Shutdown(flags tcpip.ShutdownFlags) *tcpip.Error { + return tcpip.ErrNotSupported +} + +// Listen implements tcpip.Endpoint.Listen. Packet sockets cannot be used with +// Listen, and this function always returns tcpip.ErrNotSupported. +func (ep *endpoint) Listen(backlog int) *tcpip.Error { + return tcpip.ErrNotSupported +} + +// Accept implements tcpip.Endpoint.Accept. Packet sockets cannot be used with +// Accept, and this function always returns tcpip.ErrNotSupported. +func (ep *endpoint) Accept() (tcpip.Endpoint, *waiter.Queue, *tcpip.Error) { + return nil, nil, tcpip.ErrNotSupported +} + +// Bind implements tcpip.Endpoint.Bind. +func (ep *endpoint) Bind(addr tcpip.FullAddress) *tcpip.Error { + // TODO(gvisor.dev/issue/173): Add Bind support. + + // "By default, all packets of the specified protocol type are passed + // to a packet socket. To get packets only from a specific interface + // use bind(2) specifying an address in a struct sockaddr_ll to bind + // the packet socket to an interface. Fields used for binding are + // sll_family (should be AF_PACKET), sll_protocol, and sll_ifindex." + // - packet(7). + + return tcpip.ErrNotSupported +} + +// GetLocalAddress implements tcpip.Endpoint.GetLocalAddress. +func (ep *endpoint) GetLocalAddress() (tcpip.FullAddress, *tcpip.Error) { + return tcpip.FullAddress{}, tcpip.ErrNotSupported +} + +// GetRemoteAddress implements tcpip.Endpoint.GetRemoteAddress. +func (ep *endpoint) GetRemoteAddress() (tcpip.FullAddress, *tcpip.Error) { + // Even a connected socket doesn't return a remote address. + return tcpip.FullAddress{}, tcpip.ErrNotConnected +} + +// Readiness implements tcpip.Endpoint.Readiness. +func (ep *endpoint) Readiness(mask waiter.EventMask) waiter.EventMask { + // The endpoint is always writable. + result := waiter.EventOut & mask + + // Determine whether the endpoint is readable. + if (mask & waiter.EventIn) != 0 { + ep.rcvMu.Lock() + if !ep.rcvList.Empty() || ep.rcvClosed { + result |= waiter.EventIn + } + ep.rcvMu.Unlock() + } + + return result +} + +// SetSockOpt implements tcpip.Endpoint.SetSockOpt. Packet sockets cannot be +// used with SetSockOpt, and this function always returns +// tcpip.ErrNotSupported. +func (ep *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { + return tcpip.ErrNotSupported +} + +// SetSockOptInt implements tcpip.Endpoint.SetSockOptInt. +func (ep *endpoint) SetSockOptInt(opt tcpip.SockOpt, v int) *tcpip.Error { + return tcpip.ErrUnknownProtocolOption +} + +// GetSockOptInt implements tcpip.Endpoint.GetSockOptInt. +func (ep *endpoint) GetSockOptInt(opt tcpip.SockOpt) (int, *tcpip.Error) { + return 0, tcpip.ErrNotSupported +} + +// GetSockOpt implements tcpip.Endpoint.GetSockOpt. +func (ep *endpoint) GetSockOpt(opt interface{}) *tcpip.Error { + return tcpip.ErrNotSupported +} + +// HandlePacket implements stack.PacketEndpoint.HandlePacket. +func (ep *endpoint) HandlePacket(nicID tcpip.NICID, localAddr tcpip.LinkAddress, netProto tcpip.NetworkProtocolNumber, pkt tcpip.PacketBuffer) { + ep.rcvMu.Lock() + + // Drop the packet if our buffer is currently full. + if ep.rcvClosed { + ep.rcvMu.Unlock() + ep.stack.Stats().DroppedPackets.Increment() + ep.stats.ReceiveErrors.ClosedReceiver.Increment() + return + } + + if ep.rcvBufSize >= ep.rcvBufSizeMax { + ep.rcvMu.Unlock() + ep.stack.Stats().DroppedPackets.Increment() + ep.stats.ReceiveErrors.ReceiveBufferOverflow.Increment() + return + } + + wasEmpty := ep.rcvBufSize == 0 + + // Push new packet into receive list and increment the buffer size. + var packet packet + // TODO(b/129292371): Return network protocol. + if len(pkt.LinkHeader) > 0 { + // Get info directly from the ethernet header. + hdr := header.Ethernet(pkt.LinkHeader) + packet.senderAddr = tcpip.FullAddress{ + NIC: nicID, + Addr: tcpip.Address(hdr.SourceAddress()), + } + } else { + // Guess the would-be ethernet header. + packet.senderAddr = tcpip.FullAddress{ + NIC: nicID, + Addr: tcpip.Address(localAddr), + } + } + + if ep.cooked { + // Cooked packets can simply be queued. + packet.data = pkt.Data + } else { + // Raw packets need their ethernet headers prepended before + // queueing. + var linkHeader buffer.View + if len(pkt.LinkHeader) == 0 { + // We weren't provided with an actual ethernet header, + // so fake one. + ethFields := header.EthernetFields{ + SrcAddr: tcpip.LinkAddress([]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00}), + DstAddr: localAddr, + Type: netProto, + } + fakeHeader := make(header.Ethernet, header.EthernetMinimumSize) + fakeHeader.Encode(ðFields) + linkHeader = buffer.View(fakeHeader) + } else { + linkHeader = append(buffer.View(nil), pkt.LinkHeader...) + } + combinedVV := linkHeader.ToVectorisedView() + combinedVV.Append(pkt.Data) + packet.data = combinedVV + } + packet.timestampNS = ep.stack.NowNanoseconds() + + ep.rcvList.PushBack(&packet) + ep.rcvBufSize += packet.data.Size() + + ep.rcvMu.Unlock() + ep.stats.PacketsReceived.Increment() + // Notify waiters that there's data to be read. + if wasEmpty { + ep.waiterQueue.Notify(waiter.EventIn) + } +} + +// State implements socket.Socket.State. +func (ep *endpoint) State() uint32 { + return 0 +} + +// Info returns a copy of the endpoint info. +func (ep *endpoint) Info() tcpip.EndpointInfo { + ep.mu.RLock() + // Make a copy of the endpoint info. + ret := ep.TransportEndpointInfo + ep.mu.RUnlock() + return &ret +} + +// Stats returns a pointer to the endpoint stats. +func (ep *endpoint) Stats() tcpip.EndpointStats { + return &ep.stats +} diff --git a/pkg/tcpip/transport/packet/endpoint_state.go b/pkg/tcpip/transport/packet/endpoint_state.go new file mode 100644 index 000000000..9b88f17e4 --- /dev/null +++ b/pkg/tcpip/transport/packet/endpoint_state.go @@ -0,0 +1,72 @@ +// Copyright 2018 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 packet + +import ( + "gvisor.dev/gvisor/pkg/tcpip/buffer" + "gvisor.dev/gvisor/pkg/tcpip/stack" +) + +// saveData saves packet.data field. +func (p *packet) saveData() buffer.VectorisedView { + // We cannot save p.data directly as p.data.views may alias to p.views, + // which is not allowed by state framework (in-struct pointer). + return p.data.Clone(nil) +} + +// loadData loads packet.data field. +func (p *packet) loadData(data buffer.VectorisedView) { + // NOTE: We cannot do the p.data = data.Clone(p.views[:]) optimization + // here because data.views is not guaranteed to be loaded by now. Plus, + // data.views will be allocated anyway so there really is little point + // of utilizing p.views for data.views. + p.data = data +} + +// beforeSave is invoked by stateify. +func (ep *endpoint) beforeSave() { + // Stop incoming packets from being handled (and mutate endpoint state). + // The lock will be released after saveRcvBufSizeMax(), which would have + // saved ep.rcvBufSizeMax and set it to 0 to continue blocking incoming + // packets. + ep.rcvMu.Lock() +} + +// saveRcvBufSizeMax is invoked by stateify. +func (ep *endpoint) saveRcvBufSizeMax() int { + max := ep.rcvBufSizeMax + // Make sure no new packets will be handled regardless of the lock. + ep.rcvBufSizeMax = 0 + // Release the lock acquired in beforeSave() so regular endpoint closing + // logic can proceed after save. + ep.rcvMu.Unlock() + return max +} + +// loadRcvBufSizeMax is invoked by stateify. +func (ep *endpoint) loadRcvBufSizeMax(max int) { + ep.rcvBufSizeMax = max +} + +// afterLoad is invoked by stateify. +func (ep *endpoint) afterLoad() { + // StackFromEnv is a stack used specifically for save/restore. + ep.stack = stack.StackFromEnv + + // TODO(gvisor.dev/173): Once bind is supported, choose the right NIC. + if err := ep.stack.RegisterPacketEndpoint(0, ep.netProto, ep); err != nil { + panic(*err) + } +} diff --git a/pkg/tcpip/transport/raw/BUILD b/pkg/tcpip/transport/raw/BUILD index fba598d51..00991ac8e 100644 --- a/pkg/tcpip/transport/raw/BUILD +++ b/pkg/tcpip/transport/raw/BUILD @@ -4,14 +4,14 @@ load("//tools/go_stateify:defs.bzl", "go_library") package(licenses = ["notice"]) go_template_instance( - name = "packet_list", - out = "packet_list.go", + name = "raw_packet_list", + out = "raw_packet_list.go", package = "raw", - prefix = "packet", + prefix = "rawPacket", template = "//pkg/ilist:generic_list", types = { - "Element": "*packet", - "Linker": "*packet", + "Element": "*rawPacket", + "Linker": "*rawPacket", }, ) @@ -20,8 +20,8 @@ go_library( srcs = [ "endpoint.go", "endpoint_state.go", - "packet_list.go", "protocol.go", + "raw_packet_list.go", ], importpath = "gvisor.dev/gvisor/pkg/tcpip/transport/raw", imports = ["gvisor.dev/gvisor/pkg/tcpip/buffer"], @@ -34,14 +34,7 @@ go_library( "//pkg/tcpip/header", "//pkg/tcpip/iptables", "//pkg/tcpip/stack", + "//pkg/tcpip/transport/packet", "//pkg/waiter", ], ) - -filegroup( - name = "autogen", - srcs = [ - "packet_list.go", - ], - visibility = ["//:sandbox"], -) diff --git a/pkg/tcpip/transport/raw/endpoint.go b/pkg/tcpip/transport/raw/endpoint.go index b4c660859..5aafe2615 100644 --- a/pkg/tcpip/transport/raw/endpoint.go +++ b/pkg/tcpip/transport/raw/endpoint.go @@ -17,8 +17,7 @@ // // * manually write and inspect transport layer headers and payloads // * receive all traffic of a given transport protocol (e.g. ICMP or UDP) -// * optionally write and inspect network layer and link layer headers for -// packets +// * optionally write and inspect network layer headers of packets // // Raw sockets don't have any notion of ports, and incoming packets are // demultiplexed solely by protocol number. Thus, a raw UDP endpoint will @@ -38,15 +37,11 @@ import ( ) // +stateify savable -type packet struct { - packetEntry +type rawPacket struct { + rawPacketEntry // data holds the actual packet data, including any headers and // payload. data buffer.VectorisedView `state:".(buffer.VectorisedView)"` - // views is pre-allocated space to back data. As long as the packet is - // made up of fewer than 8 buffer.Views, no extra allocation is - // necessary to store packet data. - views [8]buffer.View `state:"nosave"` // timestampNS is the unix time at which the packet was received. timestampNS int64 // senderAddr is the network address of the sender. @@ -72,7 +67,7 @@ type endpoint struct { // The following fields are used to manage the receive queue and are // protected by rcvMu. rcvMu sync.Mutex `state:"nosave"` - rcvList packetList + rcvList rawPacketList rcvBufSizeMax int `state:".(int)"` rcvBufSize int rcvClosed bool @@ -90,7 +85,6 @@ type endpoint struct { } // NewEndpoint returns a raw endpoint for the given protocols. -// TODO(b/129292371): IP_HDRINCL and AF_PACKET. func NewEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { return newEndpoint(stack, netProto, transProto, waiterQueue, true /* associated */) } @@ -187,17 +181,17 @@ func (e *endpoint) Read(addr *tcpip.FullAddress) (buffer.View, tcpip.ControlMess return buffer.View{}, tcpip.ControlMessages{}, err } - packet := e.rcvList.Front() - e.rcvList.Remove(packet) - e.rcvBufSize -= packet.data.Size() + pkt := e.rcvList.Front() + e.rcvList.Remove(pkt) + e.rcvBufSize -= pkt.data.Size() e.rcvMu.Unlock() if addr != nil { - *addr = packet.senderAddr + *addr = pkt.senderAddr } - return packet.data.ToView(), tcpip.ControlMessages{HasTimestamp: true, Timestamp: packet.timestampNS}, nil + return pkt.data.ToView(), tcpip.ControlMessages{HasTimestamp: true, Timestamp: pkt.timestampNS}, nil } // Write implements tcpip.Endpoint.Write. @@ -344,13 +338,18 @@ func (e *endpoint) finishWrite(payloadBytes []byte, route *stack.Route) (int64, switch e.NetProto { case header.IPv4ProtocolNumber: if !e.associated { - if err := route.WriteHeaderIncludedPacket(buffer.View(payloadBytes).ToVectorisedView()); err != nil { + if err := route.WriteHeaderIncludedPacket(tcpip.PacketBuffer{ + Data: buffer.View(payloadBytes).ToVectorisedView(), + }); err != nil { return 0, nil, err } break } hdr := buffer.NewPrependable(len(payloadBytes) + int(route.MaxHeaderLength())) - if err := route.WritePacket(nil /* gso */, hdr, buffer.View(payloadBytes).ToVectorisedView(), stack.NetworkHeaderParams{Protocol: e.TransProto, TTL: route.DefaultTTL(), TOS: stack.DefaultTOS}); err != nil { + if err := route.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: e.TransProto, TTL: route.DefaultTTL(), TOS: stack.DefaultTOS}, tcpip.PacketBuffer{ + Header: hdr, + Data: buffer.View(payloadBytes).ToVectorisedView(), + }); err != nil { return 0, nil, err } @@ -561,7 +560,7 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error { } // HandlePacket implements stack.RawTransportEndpoint.HandlePacket. -func (e *endpoint) HandlePacket(route *stack.Route, netHeader buffer.View, vv buffer.VectorisedView) { +func (e *endpoint) HandlePacket(route *stack.Route, pkt tcpip.PacketBuffer) { e.rcvMu.Lock() // Drop the packet if our buffer is currently full. @@ -602,16 +601,17 @@ func (e *endpoint) HandlePacket(route *stack.Route, netHeader buffer.View, vv bu wasEmpty := e.rcvBufSize == 0 // Push new packet into receive list and increment the buffer size. - packet := &packet{ + packet := &rawPacket{ senderAddr: tcpip.FullAddress{ NIC: route.NICID(), Addr: route.RemoteAddress, }, } - combinedVV := netHeader.ToVectorisedView() - combinedVV.Append(vv) - packet.data = combinedVV.Clone(packet.views[:]) + networkHeader := append(buffer.View(nil), pkt.NetworkHeader...) + combinedVV := networkHeader.ToVectorisedView() + combinedVV.Append(pkt.Data) + packet.data = combinedVV packet.timestampNS = e.stack.NowNanoseconds() e.rcvList.PushBack(packet) @@ -643,3 +643,6 @@ func (e *endpoint) Info() tcpip.EndpointInfo { func (e *endpoint) Stats() tcpip.EndpointStats { return &e.stats } + +// Wait implements stack.TransportEndpoint.Wait. +func (*endpoint) Wait() {} diff --git a/pkg/tcpip/transport/raw/endpoint_state.go b/pkg/tcpip/transport/raw/endpoint_state.go index a6c7cc43a..33bfb56cd 100644 --- a/pkg/tcpip/transport/raw/endpoint_state.go +++ b/pkg/tcpip/transport/raw/endpoint_state.go @@ -20,15 +20,15 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/stack" ) -// saveData saves packet.data field. -func (p *packet) saveData() buffer.VectorisedView { +// saveData saves rawPacket.data field. +func (p *rawPacket) saveData() buffer.VectorisedView { // We cannot save p.data directly as p.data.views may alias to p.views, // which is not allowed by state framework (in-struct pointer). return p.data.Clone(nil) } -// loadData loads packet.data field. -func (p *packet) loadData(data buffer.VectorisedView) { +// loadData loads rawPacket.data field. +func (p *rawPacket) loadData(data buffer.VectorisedView) { // NOTE: We cannot do the p.data = data.Clone(p.views[:]) optimization // here because data.views is not guaranteed to be loaded by now. Plus, // data.views will be allocated anyway so there really is little point @@ -86,7 +86,9 @@ func (ep *endpoint) Resume(s *stack.Stack) { } } - if err := ep.stack.RegisterRawTransportEndpoint(ep.RegisterNICID, ep.NetProto, ep.TransProto, ep); err != nil { - panic(err) + if ep.associated { + if err := ep.stack.RegisterRawTransportEndpoint(ep.RegisterNICID, ep.NetProto, ep.TransProto, ep); err != nil { + panic(err) + } } } diff --git a/pkg/tcpip/transport/raw/protocol.go b/pkg/tcpip/transport/raw/protocol.go index a2512d666..f30aa2a4a 100644 --- a/pkg/tcpip/transport/raw/protocol.go +++ b/pkg/tcpip/transport/raw/protocol.go @@ -17,13 +17,19 @@ package raw import ( "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/stack" + "gvisor.dev/gvisor/pkg/tcpip/transport/packet" "gvisor.dev/gvisor/pkg/waiter" ) -// EndpointFactory implements stack.UnassociatedEndpointFactory. +// EndpointFactory implements stack.RawFactory. type EndpointFactory struct{} -// NewUnassociatedRawEndpoint implements stack.UnassociatedEndpointFactory. -func (EndpointFactory) NewUnassociatedRawEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { +// NewUnassociatedEndpoint implements stack.RawFactory.NewUnassociatedEndpoint. +func (EndpointFactory) NewUnassociatedEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { return newEndpoint(stack, netProto, transProto, waiterQueue, false /* associated */) } + +// NewPacketEndpoint implements stack.RawFactory.NewPacketEndpoint. +func (EndpointFactory) NewPacketEndpoint(stack *stack.Stack, cooked bool, netProto tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { + return packet.NewEndpoint(stack, cooked, netProto, waiterQueue) +} diff --git a/pkg/tcpip/transport/tcp/BUILD b/pkg/tcpip/transport/tcp/BUILD index aed70e06f..3b353d56c 100644 --- a/pkg/tcpip/transport/tcp/BUILD +++ b/pkg/tcpip/transport/tcp/BUILD @@ -28,6 +28,7 @@ go_library( "forwarder.go", "protocol.go", "rcv.go", + "rcv_state.go", "reno.go", "sack.go", "sack_scoreboard.go", @@ -44,6 +45,7 @@ go_library( imports = ["gvisor.dev/gvisor/pkg/tcpip/buffer"], visibility = ["//visibility:public"], deps = [ + "//pkg/log", "//pkg/rand", "//pkg/sleep", "//pkg/tcpip", @@ -51,6 +53,7 @@ go_library( "//pkg/tcpip/hash/jenkins", "//pkg/tcpip/header", "//pkg/tcpip/iptables", + "//pkg/tcpip/ports", "//pkg/tcpip/seqnum", "//pkg/tcpip/stack", "//pkg/tcpip/transport/raw", @@ -60,17 +63,9 @@ go_library( ], ) -filegroup( - name = "autogen", - srcs = [ - "tcp_segment_list.go", - ], - visibility = ["//:sandbox"], -) - go_test( name = "tcp_test", - size = "small", + size = "medium", srcs = [ "dual_stack_test.go", "sack_scoreboard_test.go", diff --git a/pkg/tcpip/transport/tcp/accept.go b/pkg/tcpip/transport/tcp/accept.go index 844959fa0..5422ae80c 100644 --- a/pkg/tcpip/transport/tcp/accept.go +++ b/pkg/tcpip/transport/tcp/accept.go @@ -25,6 +25,7 @@ import ( "gvisor.dev/gvisor/pkg/rand" "gvisor.dev/gvisor/pkg/sleep" "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/seqnum" "gvisor.dev/gvisor/pkg/tcpip/stack" @@ -241,8 +242,15 @@ func (l *listenContext) createConnectingEndpoint(s *segment, iss seqnum.Value, i n.initGSO() + // Now inherit any socket options that should be inherited from the + // listening endpoint. + // In case of Forwarder listenEP will be nil and hence this check. + if l.listenEP != nil { + l.listenEP.propagateInheritableOptions(n) + } + // Register new endpoint so that packets are routed to it. - if err := n.stack.RegisterTransportEndpoint(n.boundNICID, n.effectiveNetProtos, ProtocolNumber, n.ID, n, n.reusePort, n.bindToDevice); err != nil { + if err := n.stack.RegisterTransportEndpoint(n.boundNICID, n.effectiveNetProtos, ProtocolNumber, n.ID, n, n.reusePort, n.boundBindToDevice); err != nil { n.Close() return nil, err } @@ -268,8 +276,8 @@ func (l *listenContext) createConnectingEndpoint(s *segment, iss seqnum.Value, i func (l *listenContext) createEndpointAndPerformHandshake(s *segment, opts *header.TCPSynOptions) (*endpoint, *tcpip.Error) { // Create new endpoint. irs := s.sequenceNumber - cookie := l.createCookie(s.id, irs, encodeMSS(opts.MSS)) - ep, err := l.createConnectingEndpoint(s, cookie, irs, opts) + isn := generateSecureISN(s.id, l.stack.Seed()) + ep, err := l.createConnectingEndpoint(s, isn, irs, opts) if err != nil { return nil, err } @@ -288,7 +296,7 @@ func (l *listenContext) createEndpointAndPerformHandshake(s *segment, opts *head // Perform the 3-way handshake. h := newHandshake(ep, seqnum.Size(ep.initialReceiveWindow())) - h.resetToSynRcvd(cookie, irs, opts) + h.resetToSynRcvd(isn, irs, opts) if err := h.execute(); err != nil { ep.Close() if l.listenEP != nil { @@ -297,7 +305,7 @@ func (l *listenContext) createEndpointAndPerformHandshake(s *segment, opts *head return nil, err } ep.mu.Lock() - ep.state = StateEstablished + ep.isConnectNotified = true ep.mu.Unlock() // Update the receive window scaling. We can't do it before the @@ -349,6 +357,14 @@ func (e *endpoint) deliverAccepted(n *endpoint) { } } +// propagateInheritableOptions propagates any options set on the listening +// endpoint to the newly created endpoint. +func (e *endpoint) propagateInheritableOptions(n *endpoint) { + e.mu.Lock() + n.userTimeout = e.userTimeout + e.mu.Unlock() +} + // handleSynSegment is called in its own goroutine once the listening endpoint // receives a SYN segment. It is responsible for completing the handshake and // queueing the new endpoint for acceptance. @@ -359,6 +375,7 @@ func (e *endpoint) handleSynSegment(ctx *listenContext, s *segment, opts *header defer decSynRcvdCount() defer e.decSynRcvdCount() defer s.decRef() + n, err := ctx.createEndpointAndPerformHandshake(s, opts) if err != nil { e.stack.Stats().TCP.FailedConnectionAttempts.Increment() @@ -366,6 +383,11 @@ func (e *endpoint) handleSynSegment(ctx *listenContext, s *segment, opts *header return } ctx.removePendingEndpoint(n) + // Start the protocol goroutine. + wq := &waiter.Queue{} + n.startAcceptedLoop(wq) + e.stack.Stats().TCP.PassiveConnectionOpenings.Increment() + e.deliverAccepted(n) } @@ -399,8 +421,19 @@ func (e *endpoint) acceptQueueIsFull() bool { // handleListenSegment is called when a listening endpoint receives a segment // and needs to handle it. func (e *endpoint) handleListenSegment(ctx *listenContext, s *segment) { - switch s.flags { - case header.TCPFlagSyn: + if s.flagsAreSet(header.TCPFlagSyn | header.TCPFlagAck) { + // RFC 793 section 3.4 page 35 (figure 12) outlines that a RST + // must be sent in response to a SYN-ACK while in the listen + // state to prevent completing a handshake from an old SYN. + e.sendTCP(&s.route, s.id, buffer.VectorisedView{}, e.ttl, e.sendTOS, header.TCPFlagRst, s.ackNumber, 0, 0, nil, nil) + return + } + + // TODO(b/143300739): Use the userMSS of the listening socket + // for accepted sockets. + + switch { + case s.flags == header.TCPFlagSyn: opts := parseSynSegmentOptions(s) if incSynRcvdCount() { // Only handle the syn if the following conditions hold @@ -433,19 +466,18 @@ func (e *endpoint) handleListenSegment(ctx *listenContext, s *segment) { // // Enable Timestamp option if the original syn did have // the timestamp option specified. - mss := mssForRoute(&s.route) synOpts := header.TCPSynOptions{ WS: -1, TS: opts.TS, TSVal: tcpTimeStamp(timeStampOffset()), TSEcr: opts.TSVal, - MSS: uint16(mss), + MSS: mssForRoute(&s.route), } e.sendSynTCP(&s.route, s.id, e.ttl, e.sendTOS, header.TCPFlagSyn|header.TCPFlagAck, cookie, s.sequenceNumber+1, ctx.rcvWnd, synOpts) e.stack.Stats().TCP.ListenOverflowSynCookieSent.Increment() } - case header.TCPFlagAck: + case (s.flags & header.TCPFlagAck) != 0: if e.acceptQueueIsFull() { // Silently drop the ack as the application can't accept // the connection at this point. The ack will be @@ -459,6 +491,14 @@ func (e *endpoint) handleListenSegment(ctx *listenContext, s *segment) { } if !synCookiesInUse() { + // When not using SYN cookies, as per RFC 793, section 3.9, page 64: + // Any acknowledgment is bad if it arrives on a connection still in + // the LISTEN state. An acceptable reset segment should be formed + // for any arriving ACK-bearing segment. The RST should be + // formatted as follows: + // + // <SEQ=SEG.ACK><CTL=RST> + // // Send a reset as this is an ACK for which there is no // half open connections and we are not using cookies // yet. @@ -519,7 +559,11 @@ func (e *endpoint) handleListenSegment(ctx *listenContext, s *segment) { n.tsOffset = 0 // Switch state to connected. + // We do not use transitionToStateEstablishedLocked here as there is + // no handshake state available when doing a SYN cookie based accept. + n.stack.Stats().TCP.CurrentEstablished.Increment() n.state = StateEstablished + n.isConnectNotified = true // Do the delivery in a separate goroutine so // that we don't block the listen loop in case @@ -530,6 +574,11 @@ func (e *endpoint) handleListenSegment(ctx *listenContext, s *segment) { // number of goroutines as we do check before // entering here that there was at least some // space available in the backlog. + + // Start the protocol goroutine. + wq := &waiter.Queue{} + n.startAcceptedLoop(wq) + e.stack.Stats().TCP.PassiveConnectionOpenings.Increment() go e.deliverAccepted(n) } } diff --git a/pkg/tcpip/transport/tcp/connect.go b/pkg/tcpip/transport/tcp/connect.go index 5ea036bea..cdd69f360 100644 --- a/pkg/tcpip/transport/tcp/connect.go +++ b/pkg/tcpip/transport/tcp/connect.go @@ -15,6 +15,7 @@ package tcp import ( + "encoding/binary" "sync" "time" @@ -22,6 +23,7 @@ import ( "gvisor.dev/gvisor/pkg/sleep" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" + "gvisor.dev/gvisor/pkg/tcpip/hash/jenkins" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/seqnum" "gvisor.dev/gvisor/pkg/tcpip/stack" @@ -78,9 +80,6 @@ type handshake struct { // mss is the maximum segment size received from the peer. mss uint16 - // amss is the maximum segment size advertised by us to the peer. - amss uint16 - // sndWndScale is the send window scale, as defined in RFC 1323. A // negative value means no scaling is supported by the peer. sndWndScale int @@ -142,7 +141,32 @@ func (h *handshake) resetState() { h.flags = header.TCPFlagSyn h.ackNum = 0 h.mss = 0 - h.iss = seqnum.Value(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24) + h.iss = generateSecureISN(h.ep.ID, h.ep.stack.Seed()) +} + +// generateSecureISN generates a secure Initial Sequence number based on the +// recommendation here https://tools.ietf.org/html/rfc6528#page-3. +func generateSecureISN(id stack.TransportEndpointID, seed uint32) seqnum.Value { + isnHasher := jenkins.Sum32(seed) + isnHasher.Write([]byte(id.LocalAddress)) + isnHasher.Write([]byte(id.RemoteAddress)) + portBuf := make([]byte, 2) + binary.LittleEndian.PutUint16(portBuf, id.LocalPort) + isnHasher.Write(portBuf) + binary.LittleEndian.PutUint16(portBuf, id.RemotePort) + isnHasher.Write(portBuf) + // The time period here is 64ns. This is similar to what linux uses + // generate a sequence number that overlaps less than one + // time per MSL (2 minutes). + // + // A 64ns clock ticks 10^9/64 = 15625000) times in a second. + // To wrap the whole 32 bit space would require + // 2^32/1562500 ~ 274 seconds. + // + // Which sort of guarantees that we won't reuse the ISN for a new + // connection for the same tuple for at least 274s. + isn := isnHasher.Sum32() + uint32(time.Now().UnixNano()>>6) + return seqnum.Value(isn) } // effectiveRcvWndScale returns the effective receive window scale to be used. @@ -194,6 +218,14 @@ func (h *handshake) synSentState(s *segment) *tcpip.Error { // acceptable if the ack field acknowledges the SYN. if s.flagIsSet(header.TCPFlagRst) { if s.flagIsSet(header.TCPFlagAck) && s.ackNumber == h.iss+1 { + // RFC 793, page 67, states that "If the RST bit is set [and] If the ACK + // was acceptable then signal the user "error: connection reset", drop + // the segment, enter CLOSED state, delete TCB, and return." + h.ep.mu.Lock() + h.ep.workerCleanup = true + h.ep.mu.Unlock() + // Although the RFC above calls out ECONNRESET, Linux actually returns + // ECONNREFUSED here so we do as well. return tcpip.ErrConnectionRefused } return nil @@ -228,6 +260,11 @@ func (h *handshake) synSentState(s *segment) *tcpip.Error { // and the handshake is completed. if s.flagIsSet(header.TCPFlagAck) { h.state = handshakeCompleted + + h.ep.mu.Lock() + h.ep.transitionToStateEstablishedLocked(h) + h.ep.mu.Unlock() + h.ep.sendRaw(buffer.VectorisedView{}, header.TCPFlagAck, h.iss+1, h.ackNum, h.rcvWnd>>h.effectiveRcvWndScale()) return nil } @@ -275,6 +312,15 @@ func (h *handshake) synRcvdState(s *segment) *tcpip.Error { return nil } + // RFC 793, Section 3.9, page 69, states that in the SYN-RCVD state, a + // sequence number outside of the window causes an ACK with the proper seq + // number and "After sending the acknowledgment, drop the unacceptable + // segment and return." + if !s.sequenceNumber.InWindow(h.ackNum, h.rcvWnd) { + h.ep.sendRaw(buffer.VectorisedView{}, header.TCPFlagAck, h.iss+1, h.ackNum, h.rcvWnd) + return nil + } + if s.flagIsSet(header.TCPFlagSyn) && s.sequenceNumber != h.ackNum-1 { // We received two SYN segments with different sequence // numbers, so we reset this and restart the whole @@ -319,6 +365,10 @@ func (h *handshake) synRcvdState(s *segment) *tcpip.Error { h.ep.updateRecentTimestamp(s.parsedOptions.TSVal, h.ackNum, s.sequenceNumber) } h.state = handshakeCompleted + h.ep.mu.Lock() + h.ep.transitionToStateEstablishedLocked(h) + h.ep.mu.Unlock() + return nil } @@ -445,7 +495,7 @@ func (h *handshake) execute() *tcpip.Error { // Send the initial SYN segment and loop until the handshake is // completed. - h.ep.amss = mssForRoute(&h.ep.route) + h.ep.amss = calculateAdvertisedMSS(h.ep.userMSS, h.ep.route) synOpts := header.TCPSynOptions{ WS: h.rcvWndScale, @@ -607,19 +657,14 @@ func (e *endpoint) sendTCP(r *stack.Route, id stack.TransportEndpointID, data bu return nil } -// sendTCP sends a TCP segment with the provided options via the provided -// network endpoint and under the provided identity. -func sendTCP(r *stack.Route, id stack.TransportEndpointID, data buffer.VectorisedView, ttl, tos uint8, flags byte, seq, ack seqnum.Value, rcvWnd seqnum.Size, opts []byte, gso *stack.GSO) *tcpip.Error { +func buildTCPHdr(r *stack.Route, id stack.TransportEndpointID, pkt *tcpip.PacketBuffer, flags byte, seq, ack seqnum.Value, rcvWnd seqnum.Size, opts []byte, gso *stack.GSO) { optLen := len(opts) - // Allocate a buffer for the TCP header. - hdr := buffer.NewPrependable(header.TCPMinimumSize + int(r.MaxHeaderLength()) + optLen) - - if rcvWnd > 0xffff { - rcvWnd = 0xffff - } - + hdr := &pkt.Header + packetSize := pkt.DataSize + off := pkt.DataOffset // Initialize the header. tcp := header.TCP(hdr.Prepend(header.TCPMinimumSize + optLen)) + pkt.TransportHeader = buffer.View(tcp) tcp.Encode(&header.TCPFields{ SrcPort: id.LocalPort, DstPort: id.RemotePort, @@ -631,7 +676,7 @@ func sendTCP(r *stack.Route, id stack.TransportEndpointID, data buffer.Vectorise }) copy(tcp[header.TCPMinimumSize:], opts) - length := uint16(hdr.UsedLength() + data.Size()) + length := uint16(hdr.UsedLength() + packetSize) xsum := r.PseudoHeaderChecksum(ProtocolNumber, length) // Only calculate the checksum if offloading isn't supported. if gso != nil && gso.NeedsCsum { @@ -641,14 +686,79 @@ func sendTCP(r *stack.Route, id stack.TransportEndpointID, data buffer.Vectorise // header and data and get the right sum of the TCP packet. tcp.SetChecksum(xsum) } else if r.Capabilities()&stack.CapabilityTXChecksumOffload == 0 { - xsum = header.ChecksumVV(data, xsum) + xsum = header.ChecksumVVWithOffset(pkt.Data, xsum, off, packetSize) tcp.SetChecksum(^tcp.CalculateChecksum(xsum)) } +} + +func sendTCPBatch(r *stack.Route, id stack.TransportEndpointID, data buffer.VectorisedView, ttl, tos uint8, flags byte, seq, ack seqnum.Value, rcvWnd seqnum.Size, opts []byte, gso *stack.GSO) *tcpip.Error { + optLen := len(opts) + if rcvWnd > 0xffff { + rcvWnd = 0xffff + } + + mss := int(gso.MSS) + n := (data.Size() + mss - 1) / mss + + // Allocate one big slice for all the headers. + hdrSize := header.TCPMinimumSize + int(r.MaxHeaderLength()) + optLen + buf := make([]byte, n*hdrSize) + pkts := make([]tcpip.PacketBuffer, n) + for i := range pkts { + pkts[i].Header = buffer.NewEmptyPrependableFromView(buf[i*hdrSize:][:hdrSize]) + } + + size := data.Size() + off := 0 + for i := 0; i < n; i++ { + packetSize := mss + if packetSize > size { + packetSize = size + } + size -= packetSize + pkts[i].DataOffset = off + pkts[i].DataSize = packetSize + pkts[i].Data = data + buildTCPHdr(r, id, &pkts[i], flags, seq, ack, rcvWnd, opts, gso) + off += packetSize + seq = seq.Add(seqnum.Size(packetSize)) + } + if ttl == 0 { + ttl = r.DefaultTTL() + } + sent, err := r.WritePackets(gso, pkts, stack.NetworkHeaderParams{Protocol: ProtocolNumber, TTL: ttl, TOS: tos}) + if err != nil { + r.Stats().TCP.SegmentSendErrors.IncrementBy(uint64(n - sent)) + } + r.Stats().TCP.SegmentsSent.IncrementBy(uint64(sent)) + return err +} + +// sendTCP sends a TCP segment with the provided options via the provided +// network endpoint and under the provided identity. +func sendTCP(r *stack.Route, id stack.TransportEndpointID, data buffer.VectorisedView, ttl, tos uint8, flags byte, seq, ack seqnum.Value, rcvWnd seqnum.Size, opts []byte, gso *stack.GSO) *tcpip.Error { + optLen := len(opts) + if rcvWnd > 0xffff { + rcvWnd = 0xffff + } + + if r.Loop&stack.PacketLoop == 0 && gso != nil && gso.Type == stack.GSOSW && int(gso.MSS) < data.Size() { + return sendTCPBatch(r, id, data, ttl, tos, flags, seq, ack, rcvWnd, opts, gso) + } + + pkt := tcpip.PacketBuffer{ + Header: buffer.NewPrependable(header.TCPMinimumSize + int(r.MaxHeaderLength()) + optLen), + DataOffset: 0, + DataSize: data.Size(), + Data: data, + } + buildTCPHdr(r, id, &pkt, flags, seq, ack, rcvWnd, opts, gso) + if ttl == 0 { ttl = r.DefaultTTL() } - if err := r.WritePacket(gso, hdr, data, stack.NetworkHeaderParams{Protocol: ProtocolNumber, TTL: ttl, TOS: tos}); err != nil { + if err := r.WritePacket(gso, stack.NetworkHeaderParams{Protocol: ProtocolNumber, TTL: ttl, TOS: tos}, pkt); err != nil { r.Stats().TCP.SegmentSendErrors.Increment() return err } @@ -754,10 +864,26 @@ func (e *endpoint) handleClose() *tcpip.Error { func (e *endpoint) resetConnectionLocked(err *tcpip.Error) { // Only send a reset if the connection is being aborted for a reason // other than receiving a reset. + if e.state == StateEstablished || e.state == StateCloseWait { + e.stack.Stats().TCP.EstablishedResets.Increment() + e.stack.Stats().TCP.CurrentEstablished.Decrement() + } e.state = StateError e.HardError = err - if err != tcpip.ErrConnectionReset { - e.sendRaw(buffer.VectorisedView{}, header.TCPFlagAck|header.TCPFlagRst, e.snd.sndUna, e.rcv.rcvNxt, 0) + if err != tcpip.ErrConnectionReset && err != tcpip.ErrTimeout { + // The exact sequence number to be used for the RST is the same as the + // one used by Linux. We need to handle the case of window being shrunk + // which can cause sndNxt to be outside the acceptable window on the + // receiver. + // + // See: https://www.snellman.net/blog/archive/2016-02-01-tcp-rst/ for more + // information. + sndWndEnd := e.snd.sndUna.Add(e.snd.sndWnd) + resetSeqNum := sndWndEnd + if !sndWndEnd.LessThan(e.snd.sndNxt) || e.snd.sndNxt.Size(sndWndEnd) < (1<<e.snd.sndWndScale) { + resetSeqNum = e.snd.sndNxt + } + e.sendRaw(buffer.VectorisedView{}, header.TCPFlagAck|header.TCPFlagRst, resetSeqNum, e.rcv.rcvNxt, 0) } } @@ -771,6 +897,99 @@ func (e *endpoint) completeWorkerLocked() { } } +// transitionToStateEstablisedLocked transitions a given endpoint +// to an established state using the handshake parameters provided. +// It also initializes sender/receiver if required. +func (e *endpoint) transitionToStateEstablishedLocked(h *handshake) { + if e.snd == nil { + // Transfer handshake state to TCP connection. We disable + // receive window scaling if the peer doesn't support it + // (indicated by a negative send window scale). + e.snd = newSender(e, h.iss, h.ackNum-1, h.sndWnd, h.mss, h.sndWndScale) + } + if e.rcv == nil { + rcvBufSize := seqnum.Size(e.receiveBufferSize()) + e.rcvListMu.Lock() + e.rcv = newReceiver(e, h.ackNum-1, h.rcvWnd, h.effectiveRcvWndScale(), rcvBufSize) + // Bootstrap the auto tuning algorithm. Starting at zero will + // result in a really large receive window after the first auto + // tuning adjustment. + e.rcvAutoParams.prevCopied = int(h.rcvWnd) + e.rcvListMu.Unlock() + } + h.ep.stack.Stats().TCP.CurrentEstablished.Increment() + e.state = StateEstablished +} + +// transitionToStateCloseLocked ensures that the endpoint is +// cleaned up from the transport demuxer, "before" moving to +// StateClose. This will ensure that no packet will be +// delivered to this endpoint from the demuxer when the endpoint +// is transitioned to StateClose. +func (e *endpoint) transitionToStateCloseLocked() { + if e.state == StateClose { + return + } + e.cleanupLocked() + e.state = StateClose + e.stack.Stats().TCP.EstablishedClosed.Increment() +} + +// tryDeliverSegmentFromClosedEndpoint attempts to deliver the parsed +// segment to any other endpoint other than the current one. This is called +// only when the endpoint is in StateClose and we want to deliver the segment +// to any other listening endpoint. We reply with RST if we cannot find one. +func (e *endpoint) tryDeliverSegmentFromClosedEndpoint(s *segment) { + ep := e.stack.FindTransportEndpoint(e.NetProto, e.TransProto, e.ID, &s.route) + if ep == nil { + replyWithReset(s) + s.decRef() + return + } + ep.(*endpoint).enqueueSegment(s) +} + +func (e *endpoint) handleReset(s *segment) (ok bool, err *tcpip.Error) { + if e.rcv.acceptable(s.sequenceNumber, 0) { + // RFC 793, page 37 states that "in all states + // except SYN-SENT, all reset (RST) segments are + // validated by checking their SEQ-fields." So + // we only process it if it's acceptable. + s.decRef() + e.mu.Lock() + switch e.state { + // In case of a RST in CLOSE-WAIT linux moves + // the socket to closed state with an error set + // to indicate EPIPE. + // + // Technically this seems to be at odds w/ RFC. + // As per https://tools.ietf.org/html/rfc793#section-2.7 + // page 69 the behavior for a segment arriving + // w/ RST bit set in CLOSE-WAIT is inlined below. + // + // ESTABLISHED + // FIN-WAIT-1 + // FIN-WAIT-2 + // CLOSE-WAIT + + // If the RST bit is set then, any outstanding RECEIVEs and + // SEND should receive "reset" responses. All segment queues + // should be flushed. Users should also receive an unsolicited + // general "connection reset" signal. Enter the CLOSED state, + // delete the TCB, and return. + case StateCloseWait: + e.transitionToStateCloseLocked() + e.HardError = tcpip.ErrAborted + e.mu.Unlock() + return false, nil + default: + e.mu.Unlock() + return false, tcpip.ErrConnectionReset + } + } + return true, nil +} + // handleSegments pulls segments from the queue and processes them. It returns // no error if the protocol loop should continue, an error otherwise. func (e *endpoint) handleSegments() *tcpip.Error { @@ -788,14 +1007,34 @@ func (e *endpoint) handleSegments() *tcpip.Error { } if s.flagIsSet(header.TCPFlagRst) { - if e.rcv.acceptable(s.sequenceNumber, 0) { - // RFC 793, page 37 states that "in all states - // except SYN-SENT, all reset (RST) segments are - // validated by checking their SEQ-fields." So - // we only process it if it's acceptable. - s.decRef() - return tcpip.ErrConnectionReset + if ok, err := e.handleReset(s); !ok { + return err } + } else if s.flagIsSet(header.TCPFlagSyn) { + // See: https://tools.ietf.org/html/rfc5961#section-4.1 + // 1) If the SYN bit is set, irrespective of the sequence number, TCP + // MUST send an ACK (also referred to as challenge ACK) to the remote + // peer: + // + // <SEQ=SND.NXT><ACK=RCV.NXT><CTL=ACK> + // + // After sending the acknowledgment, TCP MUST drop the unacceptable + // segment and stop processing further. + // + // By sending an ACK, the remote peer is challenged to confirm the loss + // of the previous connection and the request to start a new connection. + // A legitimate peer, after restart, would not have a TCB in the + // synchronized state. Thus, when the ACK arrives, the peer should send + // a RST segment back with the sequence number derived from the ACK + // field that caused the RST. + + // This RST will confirm that the remote peer has indeed closed the + // previous connection. Upon receipt of a valid RST, the local TCP + // endpoint MUST terminate its connection. The local TCP endpoint + // should then rely on SYN retransmission from the remote end to + // re-establish the connection. + + e.snd.sendAck() } else if s.flagIsSet(header.TCPFlagAck) { // Patch the window size in the segment according to the // send window scale. @@ -804,7 +1043,33 @@ func (e *endpoint) handleSegments() *tcpip.Error { // RFC 793, page 41 states that "once in the ESTABLISHED // state all segments must carry current acknowledgment // information." - e.rcv.handleRcvdSegment(s) + drop, err := e.rcv.handleRcvdSegment(s) + if err != nil { + s.decRef() + return err + } + if drop { + s.decRef() + continue + } + + // Now check if the received segment has caused us to transition + // to a CLOSED state, if yes then terminate processing and do + // not invoke the sender. + e.mu.RLock() + state := e.state + e.mu.RUnlock() + if state == StateClose { + // When we get into StateClose while processing from the queue, + // return immediately and let the protocolMainloop handle it. + // + // We can reach StateClose only while processing a previous segment + // or a notification from the protocolMainLoop (caller goroutine). + // This means that with this return, the segment dequeue below can + // never occur on a closed endpoint. + s.decRef() + return nil + } e.snd.handleRcvdSegment(s) } s.decRef() @@ -830,14 +1095,27 @@ func (e *endpoint) handleSegments() *tcpip.Error { // keepalive packets periodically when the connection is idle. If we don't hear // from the other side after a number of tries, we terminate the connection. func (e *endpoint) keepaliveTimerExpired() *tcpip.Error { + e.mu.RLock() + userTimeout := e.userTimeout + e.mu.RUnlock() + e.keepalive.Lock() if !e.keepalive.enabled || !e.keepalive.timer.checkExpiration() { e.keepalive.Unlock() return nil } + // If a userTimeout is set then abort the connection if it is + // exceeded. + if userTimeout != 0 && time.Since(e.rcv.lastRcvdAckTime) >= userTimeout && e.keepalive.unacked > 0 { + e.keepalive.Unlock() + e.stack.Stats().TCP.EstablishedTimedout.Increment() + return tcpip.ErrTimeout + } + if e.keepalive.unacked >= e.keepalive.count { e.keepalive.Unlock() + e.stack.Stats().TCP.EstablishedTimedout.Increment() return tcpip.ErrTimeout } @@ -854,7 +1132,6 @@ func (e *endpoint) keepaliveTimerExpired() *tcpip.Error { // whether it is enabled for this endpoint. func (e *endpoint) resetKeepaliveTimer(receivedData bool) { e.keepalive.Lock() - defer e.keepalive.Unlock() if receivedData { e.keepalive.unacked = 0 } @@ -862,6 +1139,7 @@ func (e *endpoint) resetKeepaliveTimer(receivedData bool) { // data to send. if !e.keepalive.enabled || e.snd == nil || e.snd.sndUna != e.snd.sndNxt { e.keepalive.timer.disable() + e.keepalive.Unlock() return } if e.keepalive.unacked > 0 { @@ -869,6 +1147,7 @@ func (e *endpoint) resetKeepaliveTimer(receivedData bool) { } else { e.keepalive.timer.enable(e.keepalive.idle) } + e.keepalive.Unlock() } // disableKeepaliveTimer stops the keepalive timer. @@ -903,7 +1182,6 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { } e.mu.Unlock() - // When the protocol loop exits we should wake up our waiters. e.waiterQueue.Notify(waiter.EventHUp | waiter.EventErr | waiter.EventIn | waiter.EventOut) } @@ -932,21 +1210,6 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { return err } - - // Transfer handshake state to TCP connection. We disable - // receive window scaling if the peer doesn't support it - // (indicated by a negative send window scale). - e.snd = newSender(e, h.iss, h.ackNum-1, h.sndWnd, h.mss, h.sndWndScale) - - rcvBufSize := seqnum.Size(e.receiveBufferSize()) - e.rcvListMu.Lock() - e.rcv = newReceiver(e, h.ackNum-1, h.rcvWnd, h.effectiveRcvWndScale(), rcvBufSize) - // boot strap the auto tuning algorithm. Starting at zero will - // result in a large step function on the first proper causing - // the window to just go to a really large value after the first - // RTT itself. - e.rcvAutoParams.prevCopied = initialRcvWnd - e.rcvListMu.Unlock() } e.keepalive.timer.init(&e.keepalive.waker) @@ -954,7 +1217,6 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { // Tell waiters that the endpoint is connected and writable. e.mu.Lock() - e.state = StateEstablished drained := e.drainDone != nil e.mu.Unlock() if drained { @@ -985,13 +1247,20 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { { w: &closeWaker, f: func() *tcpip.Error { - return tcpip.ErrConnectionAborted + // This means the socket is being closed due + // to the TCP_FIN_WAIT2 timeout was hit. Just + // mark the socket as closed. + e.mu.Lock() + e.transitionToStateCloseLocked() + e.mu.Unlock() + return nil }, }, { w: &e.snd.resendWaker, f: func() *tcpip.Error { if !e.snd.retransmitTimerExpired() { + e.stack.Stats().TCP.EstablishedTimedout.Increment() return tcpip.ErrTimeout } return nil @@ -1028,17 +1297,18 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { e.resetConnectionLocked(tcpip.ErrConnectionAborted) e.mu.Unlock() } + if n¬ifyClose != 0 && closeTimer == nil { - // Reset the connection 3 seconds after - // the endpoint has been closed. - // - // The timer could fire in background - // when the endpoint is drained. That's - // OK as the loop here will not honor - // the firing until the undrain arrives. - closeTimer = time.AfterFunc(3*time.Second, func() { - closeWaker.Assert() - }) + e.mu.Lock() + if e.state == StateFinWait2 && e.closed { + // The socket has been closed and we are in FIN_WAIT2 + // so start the FIN_WAIT2 timer. + closeTimer = time.AfterFunc(e.tcpLingerTimeout, func() { + closeWaker.Assert() + }) + e.waiterQueue.Notify(waiter.EventHUp | waiter.EventErr | waiter.EventIn | waiter.EventOut) + } + e.mu.Unlock() } if n¬ifyKeepaliveChanged != 0 { @@ -1054,12 +1324,20 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { return err } } - if e.state != StateError { + if e.state != StateClose && e.state != StateError { + // Only block the worker if the endpoint + // is not in closed state or error state. close(e.drainDone) <-e.undrain } } + if n¬ifyTickleWorker != 0 { + // Just a tickle notification. No need to do + // anything. + return nil + } + return nil }, }, @@ -1086,15 +1364,16 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { } e.rcvListMu.Unlock() - e.mu.RLock() + e.mu.Lock() if e.workerCleanup { e.notifyProtocolGoroutine(notifyClose) } - e.mu.RUnlock() // Main loop. Handle segments until both send and receive ends of the // connection have completed. - for !e.rcv.closed || !e.snd.closed || e.snd.sndUna != e.snd.sndNxtList { + + for e.state != StateTimeWait && e.state != StateClose && e.state != StateError { + e.mu.Unlock() e.workMu.Unlock() v, _ := s.Fetch(true) e.workMu.Lock() @@ -1110,15 +1389,168 @@ func (e *endpoint) protocolMainLoop(handshake bool) *tcpip.Error { return nil } + e.mu.Lock() + } + + state := e.state + e.mu.Unlock() + var reuseTW func() + if state == StateTimeWait { + // Disable close timer as we now entering real TIME_WAIT. + if closeTimer != nil { + closeTimer.Stop() + } + // Mark the current sleeper done so as to free all associated + // wakers. + s.Done() + // Wake up any waiters before we enter TIME_WAIT. + e.waiterQueue.Notify(waiter.EventHUp | waiter.EventErr | waiter.EventIn | waiter.EventOut) + reuseTW = e.doTimeWait() } // Mark endpoint as closed. e.mu.Lock() if e.state != StateError { - e.state = StateClose + e.stack.Stats().TCP.CurrentEstablished.Decrement() + e.transitionToStateCloseLocked() } + // Lock released below. epilogue() + // epilogue removes the endpoint from the transport-demuxer and + // unlocks e.mu. Now that no new segments can get enqueued to this + // endpoint, try to re-match the segment to a different endpoint + // as the current endpoint is closed. + for { + s := e.segmentQueue.dequeue() + if s == nil { + break + } + + e.tryDeliverSegmentFromClosedEndpoint(s) + } + + // A new SYN was received during TIME_WAIT and we need to abort + // the timewait and redirect the segment to the listener queue + if reuseTW != nil { + reuseTW() + } + return nil } + +// handleTimeWaitSegments processes segments received during TIME_WAIT +// state. +func (e *endpoint) handleTimeWaitSegments() (extendTimeWait bool, reuseTW func()) { + checkRequeue := true + for i := 0; i < maxSegmentsPerWake; i++ { + s := e.segmentQueue.dequeue() + if s == nil { + checkRequeue = false + break + } + extTW, newSyn := e.rcv.handleTimeWaitSegment(s) + if newSyn { + info := e.EndpointInfo.TransportEndpointInfo + newID := info.ID + newID.RemoteAddress = "" + newID.RemotePort = 0 + netProtos := []tcpip.NetworkProtocolNumber{info.NetProto} + // If the local address is an IPv4 address then also + // look for IPv6 dual stack endpoints that might be + // listening on the local address. + if newID.LocalAddress.To4() != "" { + netProtos = []tcpip.NetworkProtocolNumber{header.IPv4ProtocolNumber, header.IPv6ProtocolNumber} + } + for _, netProto := range netProtos { + if listenEP := e.stack.FindTransportEndpoint(netProto, info.TransProto, newID, &s.route); listenEP != nil { + tcpEP := listenEP.(*endpoint) + if EndpointState(tcpEP.State()) == StateListen { + reuseTW = func() { + tcpEP.enqueueSegment(s) + } + // We explicitly do not decRef + // the segment as it's still + // valid and being reflected to + // a listening endpoint. + return false, reuseTW + } + } + } + } + if extTW { + extendTimeWait = true + } + s.decRef() + } + if checkRequeue && !e.segmentQueue.empty() { + e.newSegmentWaker.Assert() + } + return extendTimeWait, nil +} + +// doTimeWait is responsible for handling the TCP behaviour once a socket +// enters the TIME_WAIT state. Optionally it can return a closure that +// should be executed after releasing the endpoint registrations. This is +// done in cases where a new SYN is received during TIME_WAIT that carries +// a sequence number larger than one see on the connection. +func (e *endpoint) doTimeWait() (twReuse func()) { + // Trigger a 2 * MSL time wait state. During this period + // we will drop all incoming segments. + // NOTE: On Linux this is not configurable and is fixed at 60 seconds. + timeWaitDuration := DefaultTCPTimeWaitTimeout + + // Get the stack wide configuration. + var tcpTW tcpip.TCPTimeWaitTimeoutOption + if err := e.stack.TransportProtocolOption(ProtocolNumber, &tcpTW); err == nil { + timeWaitDuration = time.Duration(tcpTW) + } + + const newSegment = 1 + const notification = 2 + const timeWaitDone = 3 + + s := sleep.Sleeper{} + s.AddWaker(&e.newSegmentWaker, newSegment) + s.AddWaker(&e.notificationWaker, notification) + + var timeWaitWaker sleep.Waker + s.AddWaker(&timeWaitWaker, timeWaitDone) + timeWaitTimer := time.AfterFunc(timeWaitDuration, timeWaitWaker.Assert) + defer timeWaitTimer.Stop() + + for { + e.workMu.Unlock() + v, _ := s.Fetch(true) + e.workMu.Lock() + switch v { + case newSegment: + extendTimeWait, reuseTW := e.handleTimeWaitSegments() + if reuseTW != nil { + return reuseTW + } + if extendTimeWait { + timeWaitTimer.Reset(timeWaitDuration) + } + case notification: + n := e.fetchNotifications() + if n¬ifyClose != 0 { + return nil + } + if n¬ifyDrain != 0 { + for !e.segmentQueue.empty() { + // Ignore extending TIME_WAIT during a + // save. For sockets in TIME_WAIT we just + // terminate the TIME_WAIT early. + e.handleTimeWaitSegments() + } + close(e.drainDone) + <-e.undrain + return nil + } + case timeWaitDone: + return nil + } + } +} diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go index a1b784b49..fe629aa40 100644 --- a/pkg/tcpip/transport/tcp/endpoint.go +++ b/pkg/tcpip/transport/tcp/endpoint.go @@ -30,6 +30,7 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/hash/jenkins" "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/tcpip/stack" "gvisor.dev/gvisor/pkg/tmutex" @@ -121,6 +122,11 @@ const ( notifyReset notifyKeepaliveChanged notifyMSSChanged + // notifyTickleWorker is used to tickle the protocol main loop during a + // restore after we update the endpoint state to the correct one. This + // ensures the loop terminates if the final state of the endpoint is + // say TIME_WAIT. + notifyTickleWorker ) // SACKInfo holds TCP SACK related information for a given endpoint. @@ -287,6 +293,7 @@ type endpoint struct { // change throughout the lifetime of the endpoint. stack *stack.Stack `state:"manual"` waiterQueue *waiter.Queue `state:"wait"` + uniqueID uint64 // lastError represents the last error that the endpoint reported; // access to it is protected by the following mutex. @@ -319,6 +326,11 @@ type endpoint struct { state EndpointState `state:".(EndpointState)"` + // origEndpointState is only used during a restore phase to save the + // endpoint state at restore time as the socket is moved to it's correct + // state. + origEndpointState EndpointState `state:"nosave"` + isPortReserved bool `state:"manual"` isRegistered bool boundNICID tcpip.NICID `state:"manual"` @@ -330,6 +342,11 @@ type endpoint struct { // disabling SO_BROADCAST, albeit as a NOOP. broadcast bool + // Values used to reserve a port or register a transport endpoint + // (which ever happens first). + boundBindToDevice tcpip.NICID + boundPortFlags ports.Flags + // effectiveNetProtos contains the network protocols actually in use. In // most cases it will only contain "netProto", but in cases like IPv6 // endpoints with v6only set to false, this could include multiple @@ -411,7 +428,7 @@ type endpoint struct { // userMSS if non-zero is the MSS value explicitly set by the user // for this endpoint using the TCP_MAXSEG setsockopt. - userMSS int + userMSS uint16 // The following fields are used to manage the send buffer. When // segments are ready to be sent, they are added to sndQueue and the @@ -458,6 +475,12 @@ type endpoint struct { // without hearing a response, the connection is closed. keepalive keepalive + // userTimeout if non-zero specifies a user specified timeout for + // a connection w/ pending data to send. A connection that has pending + // unacked data will be forcibily aborted if the timeout is reached + // without any data being acked. + userTimeout time.Duration + // pendingAccepted is a synchronization primitive used to track number // of connections that are queued up to be delivered to the accepted // channel. We use this to ensure that all goroutines blocked on writing @@ -502,6 +525,36 @@ type endpoint struct { // TODO(b/142022063): Add ability to save and restore per endpoint stats. stats Stats `state:"nosave"` + + // tcpLingerTimeout is the maximum amount of a time a socket + // a socket stays in TIME_WAIT state before being marked + // closed. + tcpLingerTimeout time.Duration + + // closed indicates that the user has called closed on the + // endpoint and at this point the endpoint is only around + // to complete the TCP shutdown. + closed bool +} + +// UniqueID implements stack.TransportEndpoint.UniqueID. +func (e *endpoint) UniqueID() uint64 { + return e.uniqueID +} + +// calculateAdvertisedMSS calculates the MSS to advertise. +// +// If userMSS is non-zero and is not greater than the maximum possible MSS for +// r, it will be used; otherwise, the maximum possible MSS will be used. +func calculateAdvertisedMSS(userMSS uint16, r stack.Route) uint16 { + // The maximum possible MSS is dependent on the route. + maxMSS := mssForRoute(&r) + + if userMSS != 0 && userMSS < maxMSS { + return userMSS + } + + return maxMSS } // StopWork halts packet processing. Only to be used in tests. @@ -550,6 +603,7 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQue interval: 75 * time.Second, count: 9, }, + uniqueID: s.UniqueID(), } var ss SendBufferSizeOption @@ -572,6 +626,16 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQue e.rcvAutoParams.disabled = !bool(mrb) } + var de DelayEnabled + if err := s.TransportProtocolOption(ProtocolNumber, &de); err == nil && de { + e.SetSockOptInt(tcpip.DelayOption, 1) + } + + var tcpLT tcpip.TCPLingerTimeoutOption + if err := s.TransportProtocolOption(ProtocolNumber, &tcpLT); err == nil { + e.tcpLingerTimeout = time.Duration(tcpLT) + } + if p := s.GetTCPProbe(); p != nil { e.probe = p } @@ -659,6 +723,13 @@ func (e *endpoint) notifyProtocolGoroutine(n uint32) { // with it. It must be called only once and with no other concurrent calls to // the endpoint. func (e *endpoint) Close() { + e.mu.Lock() + closed := e.closed + e.mu.Unlock() + if closed { + return + } + // Issue a shutdown so that the peer knows we won't send any more data // if we're connected, or stop accepting if we're listening. e.Shutdown(tcpip.ShutdownWrite | tcpip.ShutdownRead) @@ -671,14 +742,18 @@ func (e *endpoint) Close() { // in Listen() when trying to register. if e.state == StateListen && e.isPortReserved { if e.isRegistered { - e.stack.UnregisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.bindToDevice) + e.stack.StartTransportEndpointCleanup(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.boundBindToDevice) e.isRegistered = false } - e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.bindToDevice) + e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.boundPortFlags, e.boundBindToDevice) e.isPortReserved = false + e.boundBindToDevice = 0 + e.boundPortFlags = ports.Flags{} } + // Mark endpoint as closed. + e.closed = true // Either perform the local cleanup or kick the worker to make sure it // knows it needs to cleanup. tcpip.AddDanglingEndpoint(e) @@ -704,9 +779,7 @@ func (e *endpoint) closePendingAcceptableConnectionsLocked() { go func() { defer close(done) for n := range e.acceptedChan { - n.mu.Lock() - n.resetConnectionLocked(tcpip.ErrConnectionAborted) - n.mu.Unlock() + n.notifyProtocolGoroutine(notifyReset) n.Close() } }() @@ -732,16 +805,19 @@ func (e *endpoint) cleanupLocked() { e.workerCleanup = false if e.isRegistered { - e.stack.UnregisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.bindToDevice) + e.stack.StartTransportEndpointCleanup(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.boundBindToDevice) e.isRegistered = false } if e.isPortReserved { - e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.bindToDevice) + e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.boundPortFlags, e.boundBindToDevice) e.isPortReserved = false } + e.boundBindToDevice = 0 + e.boundPortFlags = ports.Flags{} e.route.Release() + e.stack.CompleteTransportEndpointCleanup(e) tcpip.DeleteDanglingEndpoint(e) } @@ -752,7 +828,9 @@ func (e *endpoint) initialReceiveWindow() int { if rcvWnd > math.MaxUint16 { rcvWnd = math.MaxUint16 } - routeWnd := InitialCwnd * int(mssForRoute(&e.route)) * 2 + + // Use the user supplied MSS, if available. + routeWnd := InitialCwnd * int(calculateAdvertisedMSS(e.userMSS, e.route)) * 2 if rcvWnd > routeWnd { rcvWnd = routeWnd } @@ -1133,16 +1211,6 @@ func (e *endpoint) SetSockOptInt(opt tcpip.SockOpt, v int) *tcpip.Error { e.sndBufMu.Unlock() return nil - default: - return nil - } -} - -// SetSockOpt sets a socket option. -func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { - // Lower 2 bits represents ECN bits. RFC 3168, section 23.1 - const inetECNMask = 3 - switch v := opt.(type) { case tcpip.DelayOption: if v == 0 { atomic.StoreUint32(&e.delay, 0) @@ -1154,6 +1222,16 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { } return nil + default: + return nil + } +} + +// SetSockOpt sets a socket option. +func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { + // Lower 2 bits represents ECN bits. RFC 3168, section 23.1 + const inetECNMask = 3 + switch v := opt.(type) { case tcpip.CorkOption: if v == 0 { atomic.StoreUint32(&e.cork, 0) @@ -1184,9 +1262,9 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { e.bindToDevice = 0 return nil } - for nicid, nic := range e.stack.NICInfo() { + for nicID, nic := range e.stack.NICInfo() { if nic.Name == string(v) { - e.bindToDevice = nicid + e.bindToDevice = nicID return nil } } @@ -1206,7 +1284,7 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { return tcpip.ErrInvalidOptionValue } e.mu.Lock() - e.userMSS = int(userMSS) + e.userMSS = uint16(userMSS) e.mu.Unlock() e.notifyProtocolGoroutine(notifyMSSChanged) return nil @@ -1262,6 +1340,12 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { e.notifyProtocolGoroutine(notifyKeepaliveChanged) return nil + case tcpip.TCPUserTimeoutOption: + e.mu.Lock() + e.userTimeout = time.Duration(v) + e.mu.Unlock() + return nil + case tcpip.BroadcastOption: e.mu.Lock() e.broadcast = v != 0 @@ -1319,6 +1403,28 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { e.mu.Unlock() return nil + case tcpip.TCPLingerTimeoutOption: + e.mu.Lock() + if v < 0 { + // Same as effectively disabling TCPLinger timeout. + v = 0 + } + var stkTCPLingerTimeout tcpip.TCPLingerTimeoutOption + if err := e.stack.TransportProtocolOption(header.TCPProtocolNumber, &stkTCPLingerTimeout); err != nil { + // We were unable to retrieve a stack config, just use + // the DefaultTCPLingerTimeout. + if v > tcpip.TCPLingerTimeoutOption(DefaultTCPLingerTimeout) { + stkTCPLingerTimeout = tcpip.TCPLingerTimeoutOption(DefaultTCPLingerTimeout) + } + } + // Cap it to the stack wide TCPLinger timeout. + if v > stkTCPLingerTimeout { + v = stkTCPLingerTimeout + } + e.tcpLingerTimeout = time.Duration(v) + e.mu.Unlock() + return nil + default: return nil } @@ -1345,6 +1451,7 @@ func (e *endpoint) GetSockOptInt(opt tcpip.SockOpt) (int, *tcpip.Error) { switch opt { case tcpip.ReceiveQueueSizeOption: return e.readyReceiveSize() + case tcpip.SendBufferSizeOption: e.sndBufMu.Lock() v := e.sndBufSize @@ -1357,8 +1464,16 @@ func (e *endpoint) GetSockOptInt(opt tcpip.SockOpt) (int, *tcpip.Error) { e.rcvListMu.Unlock() return v, nil + case tcpip.DelayOption: + var o int + if v := atomic.LoadUint32(&e.delay); v != 0 { + o = 1 + } + return o, nil + + default: + return -1, tcpip.ErrUnknownProtocolOption } - return -1, tcpip.ErrUnknownProtocolOption } // GetSockOpt implements tcpip.Endpoint.GetSockOpt. @@ -1379,13 +1494,6 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error { *o = header.TCPDefaultMSS return nil - case *tcpip.DelayOption: - *o = 0 - if v := atomic.LoadUint32(&e.delay); v != 0 { - *o = 1 - } - return nil - case *tcpip.CorkOption: *o = 0 if v := atomic.LoadUint32(&e.cork); v != 0 { @@ -1496,6 +1604,12 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error { e.keepalive.Unlock() return nil + case *tcpip.TCPUserTimeoutOption: + e.mu.Lock() + *o = tcpip.TCPUserTimeoutOption(e.userTimeout) + e.mu.Unlock() + return nil + case *tcpip.OutOfBandInlineOption: // We don't currently support disabling this option. *o = 1 @@ -1530,6 +1644,12 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error { e.mu.RUnlock() return nil + case *tcpip.TCPLingerTimeoutOption: + e.mu.Lock() + *o = tcpip.TCPLingerTimeoutOption(e.tcpLingerTimeout) + e.mu.Unlock() + return nil + default: return tcpip.ErrUnknownProtocolOption } @@ -1602,7 +1722,7 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc return tcpip.ErrAlreadyConnected } - nicid := addr.NIC + nicID := addr.NIC switch e.state { case StateBound: // If we're already bound to a NIC but the caller is requesting @@ -1611,11 +1731,11 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc break } - if nicid != 0 && nicid != e.boundNICID { + if nicID != 0 && nicID != e.boundNICID { return tcpip.ErrNoRoute } - nicid = e.boundNICID + nicID = e.boundNICID case StateInitial: // Nothing to do. We'll eventually fill-in the gaps in the ID (if any) @@ -1634,7 +1754,7 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc } // Find a route to the desired destination. - r, err := e.stack.FindRoute(nicid, e.ID.LocalAddress, addr.Addr, netProto, false /* multicastLoop */) + r, err := e.stack.FindRoute(nicID, e.ID.LocalAddress, addr.Addr, netProto, false /* multicastLoop */) if err != nil { return err } @@ -1649,7 +1769,7 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc if e.ID.LocalPort != 0 { // The endpoint is bound to a port, attempt to register it. - err := e.stack.RegisterTransportEndpoint(nicid, netProtos, ProtocolNumber, e.ID, e, e.reusePort, e.bindToDevice) + err := e.stack.RegisterTransportEndpoint(nicID, netProtos, ProtocolNumber, e.ID, e, e.reusePort, e.boundBindToDevice) if err != nil { return err } @@ -1664,7 +1784,7 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc // src IP to ensure that for a given tuple (srcIP, destIP, // destPort) the offset used as a starting point is the same to // ensure that we can cycle through the port space effectively. - h := jenkins.Sum32(e.stack.PortSeed()) + h := jenkins.Sum32(e.stack.Seed()) h.Write([]byte(e.ID.LocalAddress)) h.Write([]byte(e.ID.RemoteAddress)) portBuf := make([]byte, 2) @@ -1678,15 +1798,18 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc } // reusePort is false below because connect cannot reuse a port even if // reusePort was set. - if !e.stack.IsPortAvailable(netProtos, ProtocolNumber, e.ID.LocalAddress, p, false /* reusePort */, e.bindToDevice) { + if !e.stack.IsPortAvailable(netProtos, ProtocolNumber, e.ID.LocalAddress, p, ports.Flags{LoadBalanced: false}, e.bindToDevice) { return false, nil } id := e.ID id.LocalPort = p - switch e.stack.RegisterTransportEndpoint(nicid, netProtos, ProtocolNumber, id, e, e.reusePort, e.bindToDevice) { + switch e.stack.RegisterTransportEndpoint(nicID, netProtos, ProtocolNumber, id, e, e.reusePort, e.bindToDevice) { case nil: + // Port picking successful. Save the details of + // the selected port. e.ID = id + e.boundBindToDevice = e.bindToDevice return true, nil case tcpip.ErrPortInUse: return false, nil @@ -1702,14 +1825,14 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc // before Connect: in such a case we don't want to hold on to // reservations anymore. if e.isPortReserved { - e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, origID.LocalAddress, origID.LocalPort, e.bindToDevice) + e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, origID.LocalAddress, origID.LocalPort, e.boundPortFlags, e.boundBindToDevice) e.isPortReserved = false } e.isRegistered = true e.state = StateConnecting e.route = r.Clone() - e.boundNICID = nicid + e.boundNICID = nicID e.effectiveNetProtos = netProtos e.connectingAddress = connectingAddr @@ -1729,6 +1852,7 @@ func (e *endpoint) connect(addr tcpip.FullAddress, handshake bool, run bool) *tc e.segmentQueue.mu.Unlock() e.snd.updateMaxPayloadSize(int(e.route.MTU()), 0) e.state = StateEstablished + e.stack.Stats().TCP.CurrentEstablished.Increment() } if run { @@ -1749,9 +1873,8 @@ func (*endpoint) ConnectEndpoint(tcpip.Endpoint) *tcpip.Error { // peer. func (e *endpoint) Shutdown(flags tcpip.ShutdownFlags) *tcpip.Error { e.mu.Lock() - defer e.mu.Unlock() e.shutdownFlags |= flags - + finQueued := false switch { case e.state.connected(): // Close for read. @@ -1766,6 +1889,7 @@ func (e *endpoint) Shutdown(flags tcpip.ShutdownFlags) *tcpip.Error { // the connection with a RST. if (e.shutdownFlags&tcpip.ShutdownWrite) != 0 && rcvBufUsed > 0 { e.notifyProtocolGoroutine(notifyReset) + e.mu.Unlock() return nil } } @@ -1784,14 +1908,11 @@ func (e *endpoint) Shutdown(flags tcpip.ShutdownFlags) *tcpip.Error { s := newSegmentFromView(&e.route, e.ID, nil) e.sndQueue.PushBack(s) e.sndBufInQueue++ - + finQueued = true // Mark endpoint as closed. e.sndClosed = true e.sndBufMu.Unlock() - - // Tell protocol goroutine to close. - e.sndCloseWaker.Assert() } case e.state == StateListen: @@ -1799,11 +1920,20 @@ func (e *endpoint) Shutdown(flags tcpip.ShutdownFlags) *tcpip.Error { if flags&tcpip.ShutdownRead != 0 { e.notifyProtocolGoroutine(notifyClose) } - default: + e.mu.Unlock() return tcpip.ErrNotConnected } - + e.mu.Unlock() + if finQueued { + if e.workMu.TryLock() { + e.handleClose() + e.workMu.Unlock() + } else { + // Tell protocol goroutine to close. + e.sndCloseWaker.Assert() + } + } return nil } @@ -1844,6 +1974,15 @@ func (e *endpoint) listen(backlog int) *tcpip.Error { return nil } + if e.state == StateInitial { + // The listen is called on an unbound socket, the socket is + // automatically bound to a random free port with the local + // address set to INADDR_ANY. + if err := e.bindLocked(tcpip.FullAddress{}); err != nil { + return err + } + } + // Endpoint must be bound before it can transition to listen mode. if e.state != StateBound { e.stats.ReadErrors.InvalidEndpointState.Increment() @@ -1851,7 +1990,7 @@ func (e *endpoint) listen(backlog int) *tcpip.Error { } // Register the endpoint. - if err := e.stack.RegisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.reusePort, e.bindToDevice); err != nil { + if err := e.stack.RegisterTransportEndpoint(e.boundNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.reusePort, e.boundBindToDevice); err != nil { return err } @@ -1895,12 +2034,7 @@ func (e *endpoint) Accept() (tcpip.Endpoint, *waiter.Queue, *tcpip.Error) { return nil, nil, tcpip.ErrWouldBlock } - // Start the protocol goroutine. - wq := &waiter.Queue{} - n.startAcceptedLoop(wq) - e.stack.Stats().TCP.PassiveConnectionOpenings.Increment() - - return n, wq, nil + return n, n.waiterQueue, nil } // Bind binds the endpoint to a specific local port and optionally address. @@ -1908,6 +2042,10 @@ func (e *endpoint) Bind(addr tcpip.FullAddress) (err *tcpip.Error) { e.mu.Lock() defer e.mu.Unlock() + return e.bindLocked(addr) +} + +func (e *endpoint) bindLocked(addr tcpip.FullAddress) (err *tcpip.Error) { // Don't allow binding once endpoint is not in the initial state // anymore. This is because once the endpoint goes into a connected or // listen state, it is already bound. @@ -1932,26 +2070,33 @@ func (e *endpoint) Bind(addr tcpip.FullAddress) (err *tcpip.Error) { } } - port, err := e.stack.ReservePort(netProtos, ProtocolNumber, addr.Addr, addr.Port, e.reusePort, e.bindToDevice) + flags := ports.Flags{ + LoadBalanced: e.reusePort, + } + port, err := e.stack.ReservePort(netProtos, ProtocolNumber, addr.Addr, addr.Port, flags, e.bindToDevice) if err != nil { return err } + e.boundBindToDevice = e.bindToDevice + e.boundPortFlags = flags e.isPortReserved = true e.effectiveNetProtos = netProtos e.ID.LocalPort = port // Any failures beyond this point must remove the port registration. - defer func(bindToDevice tcpip.NICID) { + defer func(portFlags ports.Flags, bindToDevice tcpip.NICID) { if err != nil { - e.stack.ReleasePort(netProtos, ProtocolNumber, addr.Addr, port, bindToDevice) + e.stack.ReleasePort(netProtos, ProtocolNumber, addr.Addr, port, portFlags, bindToDevice) e.isPortReserved = false e.effectiveNetProtos = nil e.ID.LocalPort = 0 e.ID.LocalAddress = "" e.boundNICID = 0 + e.boundBindToDevice = 0 + e.boundPortFlags = ports.Flags{} } - }(e.bindToDevice) + }(e.boundPortFlags, e.boundBindToDevice) // If an address is specified, we must ensure that it's one of our // local addresses. @@ -2001,8 +2146,8 @@ func (e *endpoint) GetRemoteAddress() (tcpip.FullAddress, *tcpip.Error) { // HandlePacket is called by the stack when new packets arrive to this transport // endpoint. -func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv buffer.VectorisedView) { - s := newSegment(r, id, vv) +func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) { + s := newSegment(r, id, pkt) if !s.parse() { e.stack.Stats().MalformedRcvdPackets.Increment() e.stack.Stats().TCP.InvalidSegmentsReceived.Increment() @@ -2025,6 +2170,10 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv e.stack.Stats().TCP.ResetsReceived.Increment() } + e.enqueueSegment(s) +} + +func (e *endpoint) enqueueSegment(s *segment) { // Send packet to worker goroutine. if e.segmentQueue.enqueue(s) { e.newSegmentWaker.Assert() @@ -2037,7 +2186,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv } // HandleControlPacket implements stack.TransportEndpoint.HandleControlPacket. -func (e *endpoint) HandleControlPacket(id stack.TransportEndpointID, typ stack.ControlType, extra uint32, vv buffer.VectorisedView) { +func (e *endpoint) HandleControlPacket(id stack.TransportEndpointID, typ stack.ControlType, extra uint32, pkt tcpip.PacketBuffer) { switch typ { case stack.ControlPacketTooBig: e.sndBufMu.Lock() @@ -2327,11 +2476,7 @@ func (e *endpoint) completeState() stack.TCPEndpointState { return s } -func (e *endpoint) initGSO() { - if e.route.Capabilities()&stack.CapabilityGSO == 0 { - return - } - +func (e *endpoint) initHardwareGSO() { gso := &stack.GSO{} switch e.route.NetProto { case header.IPv4ProtocolNumber: @@ -2349,6 +2494,18 @@ func (e *endpoint) initGSO() { e.gso = gso } +func (e *endpoint) initGSO() { + if e.route.Capabilities()&stack.CapabilityHardwareGSO != 0 { + e.initHardwareGSO() + } else if e.route.Capabilities()&stack.CapabilitySoftwareGSO != 0 { + e.gso = &stack.GSO{ + MaxSize: e.route.GSOMaxSize(), + Type: stack.GSOSW, + NeedsCsum: false, + } + } +} + // State implements tcpip.Endpoint.State. It exports the endpoint's protocol // state for diagnostics. func (e *endpoint) State() uint32 { @@ -2371,6 +2528,23 @@ func (e *endpoint) Stats() tcpip.EndpointStats { return &e.stats } +// Wait implements stack.TransportEndpoint.Wait. +func (e *endpoint) Wait() { + waitEntry, notifyCh := waiter.NewChannelEntry(nil) + e.waiterQueue.EventRegister(&waitEntry, waiter.EventHUp) + defer e.waiterQueue.EventUnregister(&waitEntry) + for { + e.mu.Lock() + running := e.workerRunning + e.mu.Unlock() + if !running { + break + } + <-notifyCh + } +} + func mssForRoute(r *stack.Route) uint16 { + // TODO(b/143359391): Respect TCP Min and Max size. return uint16(r.MTU() - header.TCPMinimumSize) } diff --git a/pkg/tcpip/transport/tcp/endpoint_state.go b/pkg/tcpip/transport/tcp/endpoint_state.go index eae17237e..7aa4c3f0e 100644 --- a/pkg/tcpip/transport/tcp/endpoint_state.go +++ b/pkg/tcpip/transport/tcp/endpoint_state.go @@ -78,7 +78,7 @@ func (e *endpoint) beforeSave() { } fallthrough case StateError, StateClose: - for e.state == StateError && e.workerRunning { + for (e.state == StateError || e.state == StateClose) && e.workerRunning { e.mu.Unlock() time.Sleep(100 * time.Millisecond) e.mu.Lock() @@ -165,6 +165,12 @@ func (e *endpoint) loadState(state EndpointState) { // afterLoad is invoked by stateify. func (e *endpoint) afterLoad() { + // Freeze segment queue before registering to prevent any segments + // from being delivered while it is being restored. + e.origEndpointState = e.state + // Restore the endpoint to InitialState as it will be moved to + // its origEndpointState during Resume. + e.state = StateInitial stack.StackFromEnv.RegisterRestoredEndpoint(e) } @@ -173,8 +179,8 @@ func (e *endpoint) Resume(s *stack.Stack) { e.stack = s e.segmentQueue.setLimit(MaxUnprocessedSegments) e.workMu.Init() + state := e.origEndpointState - state := e.state switch state { case StateInitial, StateBound, StateListen, StateConnecting, StateEstablished: var ss SendBufferSizeOption @@ -189,12 +195,13 @@ func (e *endpoint) Resume(s *stack.Stack) { } bind := func() { - e.state = StateInitial if len(e.BindAddr) == 0 { e.BindAddr = e.ID.LocalAddress } - if err := e.Bind(tcpip.FullAddress{Addr: e.BindAddr, Port: e.ID.LocalPort}); err != nil { - panic("endpoint binding failed: " + err.String()) + addr := e.BindAddr + port := e.ID.LocalPort + if err := e.Bind(tcpip.FullAddress{Addr: addr, Port: port}); err != nil { + panic(fmt.Sprintf("endpoint binding [%v]:%d failed: %v", addr, port, err)) } } @@ -217,6 +224,16 @@ func (e *endpoint) Resume(s *stack.Stack) { if err := e.connect(tcpip.FullAddress{NIC: e.boundNICID, Addr: e.connectingAddress, Port: e.ID.RemotePort}, false, e.workerRunning); err != tcpip.ErrConnectStarted { panic("endpoint connecting failed: " + err.String()) } + e.mu.Lock() + e.state = e.origEndpointState + closed := e.closed + e.mu.Unlock() + e.notifyProtocolGoroutine(notifyTickleWorker) + if state == StateFinWait2 && closed { + // If the endpoint has been closed then make sure we notify so + // that the FIN_WAIT2 timer is started after a restore. + e.notifyProtocolGoroutine(notifyClose) + } connectedLoading.Done() case StateListen: tcpip.AsyncLoading.Add(1) @@ -263,8 +280,12 @@ func (e *endpoint) Resume(s *stack.Stack) { tcpip.AsyncLoading.Done() }() } - fallthrough + e.state = StateClose + e.stack.CompleteTransportEndpointCleanup(e) + tcpip.DeleteDanglingEndpoint(e) case StateError: + e.state = StateError + e.stack.CompleteTransportEndpointCleanup(e) tcpip.DeleteDanglingEndpoint(e) } } diff --git a/pkg/tcpip/transport/tcp/forwarder.go b/pkg/tcpip/transport/tcp/forwarder.go index 63666f0b3..4983bca81 100644 --- a/pkg/tcpip/transport/tcp/forwarder.go +++ b/pkg/tcpip/transport/tcp/forwarder.go @@ -18,7 +18,6 @@ import ( "sync" "gvisor.dev/gvisor/pkg/tcpip" - "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/seqnum" "gvisor.dev/gvisor/pkg/tcpip/stack" @@ -63,8 +62,8 @@ func NewForwarder(s *stack.Stack, rcvWnd, maxInFlight int, handler func(*Forward // // This function is expected to be passed as an argument to the // stack.SetTransportProtocolHandler function. -func (f *Forwarder) HandlePacket(r *stack.Route, id stack.TransportEndpointID, netHeader buffer.View, vv buffer.VectorisedView) bool { - s := newSegment(r, id, vv) +func (f *Forwarder) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) bool { + s := newSegment(r, id, pkt) defer s.decRef() // We only care about well-formed SYN packets. diff --git a/pkg/tcpip/transport/tcp/protocol.go b/pkg/tcpip/transport/tcp/protocol.go index db40785d3..bc718064c 100644 --- a/pkg/tcpip/transport/tcp/protocol.go +++ b/pkg/tcpip/transport/tcp/protocol.go @@ -23,6 +23,7 @@ package tcp import ( "strings" "sync" + "time" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" @@ -54,12 +55,23 @@ const ( // MaxUnprocessedSegments is the maximum number of unprocessed segments // that can be queued for a given endpoint. MaxUnprocessedSegments = 300 + + // DefaultTCPLingerTimeout is the amount of time that sockets linger in + // FIN_WAIT_2 state before being marked closed. + DefaultTCPLingerTimeout = 60 * time.Second + + // DefaultTCPTimeWaitTimeout is the amount of time that sockets linger + // in TIME_WAIT state before being marked closed. + DefaultTCPTimeWaitTimeout = 60 * time.Second ) // SACKEnabled option can be used to enable SACK support in the TCP // protocol. See: https://tools.ietf.org/html/rfc2018. type SACKEnabled bool +// DelayEnabled option can be used to enable Nagle's algorithm in the TCP protocol. +type DelayEnabled bool + // SendBufferSizeOption allows the default, min and max send buffer sizes for // TCP endpoints to be queried or configured. type SendBufferSizeOption struct { @@ -84,11 +96,14 @@ const ( type protocol struct { mu sync.Mutex sackEnabled bool + delayEnabled bool sendBufferSize SendBufferSizeOption recvBufferSize ReceiveBufferSizeOption congestionControl string availableCongestionControl []string moderateReceiveBuffer bool + tcpLingerTimeout time.Duration + tcpTimeWaitTimeout time.Duration } // Number returns the tcp protocol number. @@ -97,7 +112,7 @@ func (*protocol) Number() tcpip.TransportProtocolNumber { } // NewEndpoint creates a new tcp endpoint. -func (*protocol) NewEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { +func (p *protocol) NewEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) { return newEndpoint(stack, netProto, waiterQueue), nil } @@ -126,8 +141,8 @@ func (*protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) { // a reset is sent in response to any incoming segment except another reset. In // particular, SYNs addressed to a non-existent connection are rejected by this // means." -func (*protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, netHeader buffer.View, vv buffer.VectorisedView) bool { - s := newSegment(r, id, vv) +func (*protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) bool { + s := newSegment(r, id, pkt) defer s.decRef() if !s.parse() || !s.csumValid { @@ -147,13 +162,26 @@ func (*protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.Transpo func replyWithReset(s *segment) { // Get the seqnum from the packet if the ack flag is set. seq := seqnum.Value(0) + ack := seqnum.Value(0) + flags := byte(header.TCPFlagRst) + // As per RFC 793 page 35 (Reset Generation) + // 1. If the connection does not exist (CLOSED) then a reset is sent + // in response to any incoming segment except another reset. In + // particular, SYNs addressed to a non-existent connection are rejected + // by this means. + + // If the incoming segment has an ACK field, the reset takes its + // sequence number from the ACK field of the segment, otherwise the + // reset has sequence number zero and the ACK field is set to the sum + // of the sequence number and segment length of the incoming segment. + // The connection remains in the CLOSED state. if s.flagIsSet(header.TCPFlagAck) { seq = s.ackNumber + } else { + flags |= header.TCPFlagAck + ack = s.sequenceNumber.Add(s.logicalLen()) } - - ack := s.sequenceNumber.Add(s.logicalLen()) - - sendTCP(&s.route, s.id, buffer.VectorisedView{}, s.route.DefaultTTL(), stack.DefaultTOS, header.TCPFlagRst|header.TCPFlagAck, seq, ack, 0 /* rcvWnd */, nil /* options */, nil /* gso */) + sendTCP(&s.route, s.id, buffer.VectorisedView{}, s.route.DefaultTTL(), stack.DefaultTOS, flags, seq, ack, 0 /* rcvWnd */, nil /* options */, nil /* gso */) } // SetOption implements TransportProtocol.SetOption. @@ -165,6 +193,12 @@ func (p *protocol) SetOption(option interface{}) *tcpip.Error { p.mu.Unlock() return nil + case DelayEnabled: + p.mu.Lock() + p.delayEnabled = bool(v) + p.mu.Unlock() + return nil + case SendBufferSizeOption: if v.Min <= 0 || v.Default < v.Min || v.Default > v.Max { return tcpip.ErrInvalidOptionValue @@ -202,6 +236,24 @@ func (p *protocol) SetOption(option interface{}) *tcpip.Error { p.mu.Unlock() return nil + case tcpip.TCPLingerTimeoutOption: + if v < 0 { + v = 0 + } + p.mu.Lock() + p.tcpLingerTimeout = time.Duration(v) + p.mu.Unlock() + return nil + + case tcpip.TCPTimeWaitTimeoutOption: + if v < 0 { + v = 0 + } + p.mu.Lock() + p.tcpTimeWaitTimeout = time.Duration(v) + p.mu.Unlock() + return nil + default: return tcpip.ErrUnknownProtocolOption } @@ -216,6 +268,12 @@ func (p *protocol) Option(option interface{}) *tcpip.Error { p.mu.Unlock() return nil + case *DelayEnabled: + p.mu.Lock() + *v = DelayEnabled(p.delayEnabled) + p.mu.Unlock() + return nil + case *SendBufferSizeOption: p.mu.Lock() *v = p.sendBufferSize @@ -246,6 +304,18 @@ func (p *protocol) Option(option interface{}) *tcpip.Error { p.mu.Unlock() return nil + case *tcpip.TCPLingerTimeoutOption: + p.mu.Lock() + *v = tcpip.TCPLingerTimeoutOption(p.tcpLingerTimeout) + p.mu.Unlock() + return nil + + case *tcpip.TCPTimeWaitTimeoutOption: + p.mu.Lock() + *v = tcpip.TCPTimeWaitTimeoutOption(p.tcpTimeWaitTimeout) + p.mu.Unlock() + return nil + default: return tcpip.ErrUnknownProtocolOption } @@ -258,5 +328,7 @@ func NewProtocol() stack.TransportProtocol { recvBufferSize: ReceiveBufferSizeOption{MinBufferSize, DefaultReceiveBufferSize, MaxBufferSize}, congestionControl: ccReno, availableCongestionControl: []string{ccReno, ccCubic}, + tcpLingerTimeout: DefaultTCPLingerTimeout, + tcpTimeWaitTimeout: DefaultTCPTimeWaitTimeout, } } diff --git a/pkg/tcpip/transport/tcp/rcv.go b/pkg/tcpip/transport/tcp/rcv.go index e90f9a7d9..0a5534959 100644 --- a/pkg/tcpip/transport/tcp/rcv.go +++ b/pkg/tcpip/transport/tcp/rcv.go @@ -18,6 +18,7 @@ import ( "container/heap" "time" + "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/seqnum" ) @@ -49,16 +50,20 @@ type receiver struct { pendingRcvdSegments segmentHeap pendingBufUsed seqnum.Size pendingBufSize seqnum.Size + + // Time when the last ack was received. + lastRcvdAckTime time.Time `state:".(unixTime)"` } func newReceiver(ep *endpoint, irs seqnum.Value, rcvWnd seqnum.Size, rcvWndScale uint8, pendingBufSize seqnum.Size) *receiver { return &receiver{ - ep: ep, - rcvNxt: irs + 1, - rcvAcc: irs.Add(rcvWnd + 1), - rcvWnd: rcvWnd, - rcvWndScale: rcvWndScale, - pendingBufSize: pendingBufSize, + ep: ep, + rcvNxt: irs + 1, + rcvAcc: irs.Add(rcvWnd + 1), + rcvWnd: rcvWnd, + rcvWndScale: rcvWndScale, + pendingBufSize: pendingBufSize, + lastRcvdAckTime: time.Now(), } } @@ -204,15 +209,20 @@ func (r *receiver) consumeSegment(s *segment, segSeq seqnum.Value, segLen seqnum // Handle ACK (not FIN-ACK, which we handled above) during one of the // shutdown states. - if s.flagIsSet(header.TCPFlagAck) { + if s.flagIsSet(header.TCPFlagAck) && s.ackNumber == r.ep.snd.sndNxt { r.ep.mu.Lock() switch r.ep.state { case StateFinWait1: r.ep.state = StateFinWait2 + // Notify protocol goroutine that we have received an + // ACK to our FIN so that it can start the FIN_WAIT2 + // timer to abort connection if the other side does + // not close within 2MSL. + r.ep.notifyProtocolGoroutine(notifyClose) case StateClosing: r.ep.state = StateTimeWait case StateLastAck: - r.ep.state = StateClose + r.ep.transitionToStateCloseLocked() } r.ep.mu.Unlock() } @@ -253,25 +263,110 @@ func (r *receiver) updateRTT() { r.ep.rcvListMu.Unlock() } -// handleRcvdSegment handles TCP segments directed at the connection managed by -// r as they arrive. It is called by the protocol main loop. -func (r *receiver) handleRcvdSegment(s *segment) { +func (r *receiver) handleRcvdSegmentClosing(s *segment, state EndpointState, closed bool) (drop bool, err *tcpip.Error) { + r.ep.rcvListMu.Lock() + rcvClosed := r.ep.rcvClosed || r.closed + r.ep.rcvListMu.Unlock() + + // If we are in one of the shutdown states then we need to do + // additional checks before we try and process the segment. + switch state { + case StateCloseWait, StateClosing, StateLastAck: + if !s.sequenceNumber.LessThanEq(r.rcvNxt) { + s.decRef() + // Just drop the segment as we have + // already received a FIN and this + // segment is after the sequence number + // for the FIN. + return true, nil + } + fallthrough + case StateFinWait1: + fallthrough + case StateFinWait2: + // If we are closed for reads (either due to an + // incoming FIN or the user calling shutdown(.., + // SHUT_RD) then any data past the rcvNxt should + // trigger a RST. + endDataSeq := s.sequenceNumber.Add(seqnum.Size(s.data.Size())) + if rcvClosed && r.rcvNxt.LessThan(endDataSeq) { + s.decRef() + return true, tcpip.ErrConnectionAborted + } + if state == StateFinWait1 { + break + } + + // If it's a retransmission of an old data segment + // or a pure ACK then allow it. + if s.sequenceNumber.Add(s.logicalLen()).LessThanEq(r.rcvNxt) || + s.logicalLen() == 0 { + break + } + + // In FIN-WAIT2 if the socket is fully + // closed(not owned by application on our end + // then the only acceptable segment is a + // FIN. Since FIN can technically also carry + // data we verify that the segment carrying a + // FIN ends at exactly e.rcvNxt+1. + // + // From RFC793 page 25. + // + // For sequence number purposes, the SYN is + // considered to occur before the first actual + // data octet of the segment in which it occurs, + // while the FIN is considered to occur after + // the last actual data octet in a segment in + // which it occurs. + if closed && (!s.flagIsSet(header.TCPFlagFin) || s.sequenceNumber.Add(s.logicalLen()) != r.rcvNxt+1) { + s.decRef() + return true, tcpip.ErrConnectionAborted + } + } + // We don't care about receive processing anymore if the receive side // is closed. - if r.closed { - return + // + // NOTE: We still want to permit a FIN as it's possible only our + // end has closed and the peer is yet to send a FIN. Hence we + // compare only the payload. + segEnd := s.sequenceNumber.Add(seqnum.Size(s.data.Size())) + if rcvClosed && !segEnd.LessThanEq(r.rcvNxt) { + return true, nil + } + return false, nil +} + +// handleRcvdSegment handles TCP segments directed at the connection managed by +// r as they arrive. It is called by the protocol main loop. +func (r *receiver) handleRcvdSegment(s *segment) (drop bool, err *tcpip.Error) { + r.ep.mu.RLock() + state := r.ep.state + closed := r.ep.closed + r.ep.mu.RUnlock() + + if state != StateEstablished { + drop, err := r.handleRcvdSegmentClosing(s, state, closed) + if drop || err != nil { + return drop, err + } } segLen := seqnum.Size(s.data.Size()) segSeq := s.sequenceNumber // If the sequence number range is outside the acceptable range, just - // send an ACK. This is according to RFC 793, page 37. + // send an ACK and stop further processing of the segment. + // This is according to RFC 793, page 68. if !r.acceptable(segSeq, segLen) { r.ep.snd.sendAck() - return + return true, nil } + // Store the time of the last ack. + r.lastRcvdAckTime = time.Now() + // Defer segment processing if it can't be consumed now. if !r.consumeSegment(s, segSeq, segLen) { if segLen > 0 || s.flagIsSet(header.TCPFlagFin) { @@ -288,7 +383,7 @@ func (r *receiver) handleRcvdSegment(s *segment) { // have to retransmit. r.ep.snd.sendAck() } - return + return false, nil } // Since we consumed a segment update the receiver's RTT estimate @@ -315,4 +410,67 @@ func (r *receiver) handleRcvdSegment(s *segment) { r.pendingBufUsed -= s.logicalLen() s.decRef() } + return false, nil +} + +// handleTimeWaitSegment handles inbound segments received when the endpoint +// has entered the TIME_WAIT state. +func (r *receiver) handleTimeWaitSegment(s *segment) (resetTimeWait bool, newSyn bool) { + segSeq := s.sequenceNumber + segLen := seqnum.Size(s.data.Size()) + + // Just silently drop any RST packets in TIME_WAIT. We do not support + // TIME_WAIT assasination as a result we confirm w/ fix 1 as described + // in https://tools.ietf.org/html/rfc1337#section-3. + if s.flagIsSet(header.TCPFlagRst) { + return false, false + } + + // If it's a SYN and the sequence number is higher than any seen before + // for this connection then try and redirect it to a listening endpoint + // if available. + // + // RFC 1122: + // "When a connection is [...] on TIME-WAIT state [...] + // [a TCP] MAY accept a new SYN from the remote TCP to + // reopen the connection directly, if it: + + // (1) assigns its initial sequence number for the new + // connection to be larger than the largest sequence + // number it used on the previous connection incarnation, + // and + + // (2) returns to TIME-WAIT state if the SYN turns out + // to be an old duplicate". + if s.flagIsSet(header.TCPFlagSyn) && r.rcvNxt.LessThan(segSeq) { + + return false, true + } + + // Drop the segment if it does not contain an ACK. + if !s.flagIsSet(header.TCPFlagAck) { + return false, false + } + + // Update Timestamp if required. See RFC7323, section-4.3. + if r.ep.sendTSOk && s.parsedOptions.TS { + r.ep.updateRecentTimestamp(s.parsedOptions.TSVal, r.ep.snd.maxSentAck, segSeq) + } + + if segSeq.Add(1) == r.rcvNxt && s.flagIsSet(header.TCPFlagFin) { + // If it's a FIN-ACK then resetTimeWait and send an ACK, as it + // indicates our final ACK could have been lost. + r.ep.snd.sendAck() + return true, false + } + + // If the sequence number range is outside the acceptable range or + // carries data then just send an ACK. This is according to RFC 793, + // page 37. + // + // NOTE: In TIME_WAIT the only acceptable sequence number is rcvNxt. + if segSeq != r.rcvNxt || segLen != 0 { + r.ep.snd.sendAck() + } + return false, false } diff --git a/pkg/tcpip/transport/tcp/rcv_state.go b/pkg/tcpip/transport/tcp/rcv_state.go new file mode 100644 index 000000000..2bf21a2e7 --- /dev/null +++ b/pkg/tcpip/transport/tcp/rcv_state.go @@ -0,0 +1,29 @@ +// 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 tcp + +import ( + "time" +) + +// saveLastRcvdAckTime is invoked by stateify. +func (r *receiver) saveLastRcvdAckTime() unixTime { + return unixTime{r.lastRcvdAckTime.Unix(), r.lastRcvdAckTime.UnixNano()} +} + +// loadLastRcvdAckTime is invoked by stateify. +func (r *receiver) loadLastRcvdAckTime(unix unixTime) { + r.lastRcvdAckTime = time.Unix(unix.second, unix.nano) +} diff --git a/pkg/tcpip/transport/tcp/segment.go b/pkg/tcpip/transport/tcp/segment.go index ea725d513..1c10da5ca 100644 --- a/pkg/tcpip/transport/tcp/segment.go +++ b/pkg/tcpip/transport/tcp/segment.go @@ -18,6 +18,7 @@ import ( "sync/atomic" "time" + "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" "gvisor.dev/gvisor/pkg/tcpip/seqnum" @@ -60,13 +61,13 @@ type segment struct { xmitTime time.Time `state:".(unixTime)"` } -func newSegment(r *stack.Route, id stack.TransportEndpointID, vv buffer.VectorisedView) *segment { +func newSegment(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) *segment { s := &segment{ refCnt: 1, id: id, route: r.Clone(), } - s.data = vv.Clone(s.views[:]) + s.data = pkt.Data.Clone(s.views[:]) s.rcvdTime = time.Now() return s } @@ -99,8 +100,14 @@ func (s *segment) clone() *segment { return t } -func (s *segment) flagIsSet(flag uint8) bool { - return (s.flags & flag) != 0 +// flagIsSet checks if at least one flag in flags is set in s.flags. +func (s *segment) flagIsSet(flags uint8) bool { + return s.flags&flags != 0 +} + +// flagsAreSet checks if all flags in flags are set in s.flags. +func (s *segment) flagsAreSet(flags uint8) bool { + return s.flags&flags == flags } func (s *segment) decRef() { diff --git a/pkg/tcpip/transport/tcp/snd.go b/pkg/tcpip/transport/tcp/snd.go index 8332a0179..8a947dc66 100644 --- a/pkg/tcpip/transport/tcp/snd.go +++ b/pkg/tcpip/transport/tcp/snd.go @@ -28,8 +28,11 @@ import ( ) const ( - // minRTO is the minimum allowed value for the retransmit timeout. - minRTO = 200 * time.Millisecond + // MinRTO is the minimum allowed value for the retransmit timeout. + MinRTO = 200 * time.Millisecond + + // MaxRTO is the maximum allowed value for the retransmit timeout. + MaxRTO = 120 * time.Second // InitialCwnd is the initial congestion window. InitialCwnd = 10 @@ -134,6 +137,10 @@ type sender struct { // rttMeasureTime is the time when the rttMeasureSeqNum was sent. rttMeasureTime time.Time `state:".(unixTime)"` + // firstRetransmittedSegXmitTime is the original transmit time of + // the first segment that was retransmitted due to RTO expiration. + firstRetransmittedSegXmitTime time.Time `state:".(unixTime)"` + closed bool writeNext *segment writeList segmentList @@ -392,8 +399,8 @@ func (s *sender) updateRTO(rtt time.Duration) { s.rto = s.rtt.srtt + 4*s.rtt.rttvar s.rtt.Unlock() - if s.rto < minRTO { - s.rto = minRTO + if s.rto < MinRTO { + s.rto = MinRTO } } @@ -438,8 +445,30 @@ func (s *sender) retransmitTimerExpired() bool { s.ep.stack.Stats().TCP.Timeouts.Increment() s.ep.stats.SendErrors.Timeouts.Increment() - // Give up if we've waited more than a minute since the last resend. - if s.rto >= 60*time.Second { + // Give up if we've waited more than a minute since the last resend or + // if a user time out is set and we have exceeded the user specified + // timeout since the first retransmission. + s.ep.mu.RLock() + uto := s.ep.userTimeout + s.ep.mu.RUnlock() + + if s.firstRetransmittedSegXmitTime.IsZero() { + // We store the original xmitTime of the segment that we are + // about to retransmit as the retransmission time. This is + // required as by the time the retransmitTimer has expired the + // segment has already been sent and unacked for the RTO at the + // time the segment was sent. + s.firstRetransmittedSegXmitTime = s.writeList.Front().xmitTime + } + + elapsed := time.Since(s.firstRetransmittedSegXmitTime) + remaining := MaxRTO + if uto != 0 { + // Cap to the user specified timeout if one is specified. + remaining = uto - elapsed + } + + if remaining <= 0 || s.rto >= MaxRTO { return false } @@ -447,6 +476,11 @@ func (s *sender) retransmitTimerExpired() bool { // below. s.rto *= 2 + // Cap RTO to remaining time. + if s.rto > remaining { + s.rto = remaining + } + // See: https://tools.ietf.org/html/rfc6582#section-3.2 Step 4. // // Retransmit timeouts: @@ -1168,6 +1202,8 @@ func (s *sender) handleRcvdSegment(seg *segment) { // RFC 6298 Rule 5.3 if s.sndUna == s.sndNxt { s.outstanding = 0 + // Reset firstRetransmittedSegXmitTime to the zero value. + s.firstRetransmittedSegXmitTime = time.Time{} s.resendTimer.disable() } } diff --git a/pkg/tcpip/transport/tcp/snd_state.go b/pkg/tcpip/transport/tcp/snd_state.go index 12eff8afc..8b20c3455 100644 --- a/pkg/tcpip/transport/tcp/snd_state.go +++ b/pkg/tcpip/transport/tcp/snd_state.go @@ -48,3 +48,13 @@ func (s *sender) loadRttMeasureTime(unix unixTime) { func (s *sender) afterLoad() { s.resendTimer.init(&s.resendWaker) } + +// saveFirstRetransmittedSegXmitTime is invoked by stateify. +func (s *sender) saveFirstRetransmittedSegXmitTime() unixTime { + return unixTime{s.firstRetransmittedSegXmitTime.Unix(), s.firstRetransmittedSegXmitTime.UnixNano()} +} + +// loadFirstRetransmittedSegXmitTime is invoked by stateify. +func (s *sender) loadFirstRetransmittedSegXmitTime(unix unixTime) { + s.firstRetransmittedSegXmitTime = time.Unix(unix.second, unix.nano) +} diff --git a/pkg/tcpip/transport/tcp/tcp_test.go b/pkg/tcpip/transport/tcp/tcp_test.go index 6d022a266..e8fe4dab5 100644 --- a/pkg/tcpip/transport/tcp/tcp_test.go +++ b/pkg/tcpip/transport/tcp/tcp_test.go @@ -75,6 +75,20 @@ func TestGiveUpConnect(t *testing.T) { if err := ep.GetSockOpt(tcpip.ErrorOption{}); err != tcpip.ErrAborted { t.Fatalf("got ep.GetSockOpt(tcpip.ErrorOption{}) = %v, want = %v", err, tcpip.ErrAborted) } + + // Call Connect again to retreive the handshake failure status + // and stats updates. + if err := ep.Connect(tcpip.FullAddress{Addr: context.TestAddr, Port: context.TestPort}); err != tcpip.ErrAborted { + t.Fatalf("got ep.Connect(...) = %v, want = %v", err, tcpip.ErrAborted) + } + + if got := c.Stack().Stats().TCP.FailedConnectionAttempts.Value(); got != 1 { + t.Errorf("got stats.TCP.FailedConnectionAttempts.Value() = %v, want = 1", got) + } + + if got := c.Stack().Stats().TCP.CurrentEstablished.Value(); got != 0 { + t.Errorf("got stats.TCP.CurrentEstablished.Value() = %v, want = 0", got) + } } func TestConnectIncrementActiveConnection(t *testing.T) { @@ -206,17 +220,18 @@ func TestTCPResetSentForACKWhenNotUsingSynCookies(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() + // Set TCPLingerTimeout to 5 seconds so that sockets are marked closed wq := &waiter.Queue{} ep, err := c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, wq) if err != nil { - t.Fatalf("NewEndpoint failed: %v", err) + t.Fatalf("NewEndpoint failed: %s", err) } if err := ep.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { - t.Fatalf("Bind failed: %v", err) + t.Fatalf("Bind failed: %s", err) } if err := ep.Listen(10); err != nil { - t.Fatalf("Listen failed: %v", err) + t.Fatalf("Listen failed: %s", err) } // Send a SYN request. @@ -256,7 +271,7 @@ func TestTCPResetSentForACKWhenNotUsingSynCookies(t *testing.T) { case <-ch: c.EP, _, err = ep.Accept() if err != nil { - t.Fatalf("Accept failed: %v", err) + t.Fatalf("Accept failed: %s", err) } case <-time.After(1 * time.Second): @@ -264,6 +279,13 @@ func TestTCPResetSentForACKWhenNotUsingSynCookies(t *testing.T) { } } + // Lower stackwide TIME_WAIT timeout so that the reservations + // are released instantly on Close. + tcpTW := tcpip.TCPTimeWaitTimeoutOption(1 * time.Millisecond) + if err := c.Stack().SetTransportProtocolOption(tcp.ProtocolNumber, tcpTW); err != nil { + t.Fatalf("e.stack.SetTransportProtocolOption(%d, %s) = %s", tcp.ProtocolNumber, tcpTW, err) + } + c.EP.Close() checker.IPv4(t, c.GetPacket(), checker.TCP( checker.SrcPort(context.StackPort), @@ -285,6 +307,11 @@ func TestTCPResetSentForACKWhenNotUsingSynCookies(t *testing.T) { // Get the ACK to the FIN we just sent. c.GetPacket() + // Since an active close was done we need to wait for a little more than + // tcpLingerTimeout for the port reservations to be released and the + // socket to move to a CLOSED state. + time.Sleep(20 * time.Millisecond) + // Now resend the same ACK, this ACK should generate a RST as there // should be no endpoint in SYN-RCVD state and we are not using // syn-cookies yet. The reason we send the same ACK is we need a valid @@ -296,8 +323,8 @@ func TestTCPResetSentForACKWhenNotUsingSynCookies(t *testing.T) { checker.SrcPort(context.StackPort), checker.DstPort(context.TestPort), checker.SeqNum(uint32(c.IRS+1)), - checker.AckNum(uint32(iss)+1), - checker.TCPFlags(header.TCPFlagRst|header.TCPFlagAck))) + checker.AckNum(0), + checker.TCPFlags(header.TCPFlagRst))) } func TestTCPResetsReceivedIncrement(t *testing.T) { @@ -376,6 +403,13 @@ func TestConnectResetAfterClose(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() + // Set TCPLinger to 3 seconds so that sockets are marked closed + // after 3 second in FIN_WAIT2 state. + tcpLingerTimeout := 3 * time.Second + if err := c.Stack().SetTransportProtocolOption(tcp.ProtocolNumber, tcpip.TCPLingerTimeoutOption(tcpLingerTimeout)); err != nil { + t.Fatalf("c.stack.SetTransportProtocolOption(tcp, tcpip.TCPLingerTimeoutOption(%d) failed: %s", tcpLingerTimeout, err) + } + c.CreateConnected(789, 30000, -1 /* epRcvBuf */) ep := c.EP c.EP = nil @@ -396,12 +430,24 @@ func TestConnectResetAfterClose(t *testing.T) { DstPort: c.Port, Flags: header.TCPFlagAck, SeqNum: 790, - AckNum: c.IRS.Add(1), + AckNum: c.IRS.Add(2), + RcvWnd: 30000, + }) + + // Wait for the ep to give up waiting for a FIN. + time.Sleep(tcpLingerTimeout + 1*time.Second) + + // Now send an ACK and it should trigger a RST as the endpoint should + // not exist anymore. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: c.Port, + Flags: header.TCPFlagAck, + SeqNum: 790, + AckNum: c.IRS.Add(2), RcvWnd: 30000, }) - // Wait for the ep to give up waiting for a FIN, and send a RST. - time.Sleep(3 * time.Second) for { b := c.GetPacket() tcpHdr := header.TCP(header.IPv4(b).Payload()) @@ -413,15 +459,128 @@ func TestConnectResetAfterClose(t *testing.T) { checker.IPv4(t, b, checker.TCP( checker.DstPort(context.TestPort), - checker.SeqNum(uint32(c.IRS)+1), - checker.AckNum(790), - checker.TCPFlags(header.TCPFlagAck|header.TCPFlagRst), + checker.SeqNum(uint32(c.IRS)+2), + checker.AckNum(0), + checker.TCPFlags(header.TCPFlagRst), ), ) break } } +// TestClosingWithEnqueuedSegments tests handling of still enqueued segments +// when the endpoint transitions to StateClose. The in-flight segments would be +// re-enqueued to a any listening endpoint. +func TestClosingWithEnqueuedSegments(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.CreateConnected(789, 30000, -1 /* epRcvBuf */) + ep := c.EP + c.EP = nil + + if got, want := tcp.EndpointState(ep.State()), tcp.StateEstablished; got != want { + t.Errorf("Unexpected endpoint state: want %v, got %v", want, got) + } + + // Send a FIN for ESTABLISHED --> CLOSED-WAIT + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: c.Port, + Flags: header.TCPFlagFin | header.TCPFlagAck, + SeqNum: 790, + AckNum: c.IRS.Add(1), + RcvWnd: 30000, + }) + + // Get the ACK for the FIN we sent. + checker.IPv4(t, c.GetPacket(), + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS)+1), + checker.AckNum(791), + checker.TCPFlags(header.TCPFlagAck), + ), + ) + + if got, want := tcp.EndpointState(ep.State()), tcp.StateCloseWait; got != want { + t.Errorf("Unexpected endpoint state: want %v, got %v", want, got) + } + + // Close the application endpoint for CLOSE_WAIT --> LAST_ACK + ep.Close() + + // Get the FIN + checker.IPv4(t, c.GetPacket(), + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS)+1), + checker.AckNum(791), + checker.TCPFlags(header.TCPFlagAck|header.TCPFlagFin), + ), + ) + + if got, want := tcp.EndpointState(ep.State()), tcp.StateLastAck; got != want { + t.Errorf("Unexpected endpoint state: want %v, got %v", want, got) + } + + // Pause the endpoint`s protocolMainLoop. + ep.(interface{ StopWork() }).StopWork() + + // Enqueue last ACK followed by an ACK matching the endpoint + // + // Send Last ACK for LAST_ACK --> CLOSED + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: c.Port, + Flags: header.TCPFlagAck, + SeqNum: 791, + AckNum: c.IRS.Add(2), + RcvWnd: 30000, + }) + + // Send a packet with ACK set, this would generate RST when + // not using SYN cookies as in this test. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: c.Port, + Flags: header.TCPFlagAck | header.TCPFlagFin, + SeqNum: 792, + AckNum: c.IRS.Add(2), + RcvWnd: 30000, + }) + + // Unpause endpoint`s protocolMainLoop. + ep.(interface{ ResumeWork() }).ResumeWork() + + // Wait for the protocolMainLoop to resume and update state. + time.Sleep(10 * time.Millisecond) + + // Expect the endpoint to be closed. + if got, want := tcp.EndpointState(ep.State()), tcp.StateClose; got != want { + t.Errorf("Unexpected endpoint state: want %v, got %v", want, got) + } + + if got := c.Stack().Stats().TCP.EstablishedClosed.Value(); got != 1 { + t.Errorf("got c.Stack().Stats().TCP.EstablishedClosed = %v, want = 1", got) + } + + if got := c.Stack().Stats().TCP.CurrentEstablished.Value(); got != 0 { + t.Errorf("got stats.TCP.CurrentEstablished.Value() = %v, want = 0", got) + } + + // Check if the endpoint was moved to CLOSED and netstack a reset in + // response to the ACK packet that we sent after last-ACK. + checker.IPv4(t, c.GetPacket(), + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS)+2), + checker.AckNum(0), + checker.TCPFlags(header.TCPFlagRst), + ), + ) +} + func TestSimpleReceive(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() @@ -474,6 +633,352 @@ func TestSimpleReceive(t *testing.T) { ) } +// TestUserSuppliedMSSOnConnectV4 tests that the user supplied MSS is used when +// creating a new active IPv4 TCP socket. It should be present in the sent TCP +// SYN segment. +func TestUserSuppliedMSSOnConnectV4(t *testing.T) { + const mtu = 5000 + const maxMSS = mtu - header.IPv4MinimumSize - header.TCPMinimumSize + tests := []struct { + name string + setMSS uint16 + expMSS uint16 + }{ + { + "EqualToMaxMSS", + maxMSS, + maxMSS, + }, + { + "LessThanMTU", + maxMSS - 1, + maxMSS - 1, + }, + { + "GreaterThanMTU", + maxMSS + 1, + maxMSS, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + c := context.New(t, mtu) + defer c.Cleanup() + + c.Create(-1) + + // Set the MSS socket option. + opt := tcpip.MaxSegOption(test.setMSS) + if err := c.EP.SetSockOpt(opt); err != nil { + t.Fatalf("SetSockOpt(%#v) failed: %s", opt, err) + } + + // Get expected window size. + rcvBufSize, err := c.EP.GetSockOptInt(tcpip.ReceiveBufferSizeOption) + if err != nil { + t.Fatalf("GetSockOpt(%v) failed: %s", tcpip.ReceiveBufferSizeOption, err) + } + ws := tcp.FindWndScale(seqnum.Size(rcvBufSize)) + + // Start connection attempt to IPv4 address. + if err := c.EP.Connect(tcpip.FullAddress{Addr: context.TestAddr, Port: context.TestPort}); err != tcpip.ErrConnectStarted { + t.Fatalf("Unexpected return value from Connect: %v", err) + } + + // Receive SYN packet with our user supplied MSS. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagSyn), + checker.TCPSynOptions(header.TCPSynOptions{MSS: test.expMSS, WS: ws}))) + }) + } +} + +// TestUserSuppliedMSSOnConnectV6 tests that the user supplied MSS is used when +// creating a new active IPv6 TCP socket. It should be present in the sent TCP +// SYN segment. +func TestUserSuppliedMSSOnConnectV6(t *testing.T) { + const mtu = 5000 + const maxMSS = mtu - header.IPv6MinimumSize - header.TCPMinimumSize + tests := []struct { + name string + setMSS uint16 + expMSS uint16 + }{ + { + "EqualToMaxMSS", + maxMSS, + maxMSS, + }, + { + "LessThanMTU", + maxMSS - 1, + maxMSS - 1, + }, + { + "GreaterThanMTU", + maxMSS + 1, + maxMSS, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + c := context.New(t, mtu) + defer c.Cleanup() + + c.CreateV6Endpoint(true) + + // Set the MSS socket option. + opt := tcpip.MaxSegOption(test.setMSS) + if err := c.EP.SetSockOpt(opt); err != nil { + t.Fatalf("SetSockOpt(%#v) failed: %s", opt, err) + } + + // Get expected window size. + rcvBufSize, err := c.EP.GetSockOptInt(tcpip.ReceiveBufferSizeOption) + if err != nil { + t.Fatalf("GetSockOpt(%v) failed: %s", tcpip.ReceiveBufferSizeOption, err) + } + ws := tcp.FindWndScale(seqnum.Size(rcvBufSize)) + + // Start connection attempt to IPv6 address. + if err := c.EP.Connect(tcpip.FullAddress{Addr: context.TestV6Addr, Port: context.TestPort}); err != tcpip.ErrConnectStarted { + t.Fatalf("Unexpected return value from Connect: %v", err) + } + + // Receive SYN packet with our user supplied MSS. + checker.IPv6(t, c.GetV6Packet(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagSyn), + checker.TCPSynOptions(header.TCPSynOptions{MSS: test.expMSS, WS: ws}))) + }) + } +} + +func TestSendRstOnListenerRxSynAckV4(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.Create(-1) + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatal("Bind failed:", err) + } + + if err := c.EP.Listen(10); err != nil { + t.Fatal("Listen failed:", err) + } + + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn | header.TCPFlagAck, + SeqNum: 100, + AckNum: 200, + }) + + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagRst), + checker.SeqNum(200))) +} + +func TestSendRstOnListenerRxSynAckV6(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.CreateV6Endpoint(true) + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatal("Bind failed:", err) + } + + if err := c.EP.Listen(10); err != nil { + t.Fatal("Listen failed:", err) + } + + c.SendV6Packet(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn | header.TCPFlagAck, + SeqNum: 100, + AckNum: 200, + }) + + checker.IPv6(t, c.GetV6Packet(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagRst), + checker.SeqNum(200))) +} + +// TestTCPAckBeforeAcceptV4 tests that once the 3-way handshake is complete, +// peers can send data and expect a response within a reasonable ammount of time +// without calling Accept on the listening endpoint first. +// +// This test uses IPv4. +func TestTCPAckBeforeAcceptV4(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.Create(-1) + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatal("Bind failed:", err) + } + + if err := c.EP.Listen(10); err != nil { + t.Fatal("Listen failed:", err) + } + + irs, iss := executeHandshake(t, c, context.TestPort, false /* synCookiesInUse */) + + // Send data before accepting the connection. + c.SendPacket([]byte{1, 2, 3, 4}, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: irs + 1, + AckNum: iss + 1, + }) + + // Receive ACK for the data we sent. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagAck), + checker.SeqNum(uint32(iss+1)), + checker.AckNum(uint32(irs+5)))) +} + +// TestTCPAckBeforeAcceptV6 tests that once the 3-way handshake is complete, +// peers can send data and expect a response within a reasonable ammount of time +// without calling Accept on the listening endpoint first. +// +// This test uses IPv6. +func TestTCPAckBeforeAcceptV6(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.CreateV6Endpoint(true) + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatal("Bind failed:", err) + } + + if err := c.EP.Listen(10); err != nil { + t.Fatal("Listen failed:", err) + } + + irs, iss := executeV6Handshake(t, c, context.TestPort, false /* synCookiesInUse */) + + // Send data before accepting the connection. + c.SendV6Packet([]byte{1, 2, 3, 4}, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: irs + 1, + AckNum: iss + 1, + }) + + // Receive ACK for the data we sent. + checker.IPv6(t, c.GetV6Packet(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagAck), + checker.SeqNum(uint32(iss+1)), + checker.AckNum(uint32(irs+5)))) +} + +func TestSendRstOnListenerRxAckV4(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.Create(-1 /* epRcvBuf */) + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatal("Bind failed:", err) + } + + if err := c.EP.Listen(10 /* backlog */); err != nil { + t.Fatal("Listen failed:", err) + } + + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagFin | header.TCPFlagAck, + SeqNum: 100, + AckNum: 200, + }) + + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagRst), + checker.SeqNum(200))) +} + +func TestSendRstOnListenerRxAckV6(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.CreateV6Endpoint(true /* v6Only */) + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatal("Bind failed:", err) + } + + if err := c.EP.Listen(10 /* backlog */); err != nil { + t.Fatal("Listen failed:", err) + } + + c.SendV6Packet(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagFin | header.TCPFlagAck, + SeqNum: 100, + AckNum: 200, + }) + + checker.IPv6(t, c.GetV6Packet(), checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagRst), + checker.SeqNum(200))) +} + +// TestListenShutdown tests for the listening endpoint not processing +// any receive when it is on read shutdown. +func TestListenShutdown(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.Create(-1 /* epRcvBuf */) + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatal("Bind failed:", err) + } + + if err := c.EP.Listen(10 /* backlog */); err != nil { + t.Fatal("Listen failed:", err) + } + + if err := c.EP.Shutdown(tcpip.ShutdownRead); err != nil { + t.Fatal("Shutdown failed:", err) + } + + // Wait for the endpoint state to be propagated. + time.Sleep(10 * time.Millisecond) + + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: 100, + AckNum: 200, + }) + + c.CheckNoPacket("Packet received when listening socket was shutdown") +} + func TestTOSV4(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() @@ -635,6 +1140,71 @@ func TestConnectBindToDevice(t *testing.T) { } } +func TestRstOnSynSent(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + // Create an endpoint, don't handshake because we want to interfere with the + // handshake process. + c.Create(-1) + + // Start connection attempt. + waitEntry, ch := waiter.NewChannelEntry(nil) + c.WQ.EventRegister(&waitEntry, waiter.EventOut) + defer c.WQ.EventUnregister(&waitEntry) + + addr := tcpip.FullAddress{Addr: context.TestAddr, Port: context.TestPort} + if err := c.EP.Connect(addr); err != tcpip.ErrConnectStarted { + t.Fatalf("got Connect(%+v) = %v, want %s", addr, err, tcpip.ErrConnectStarted) + } + + // Receive SYN packet. + b := c.GetPacket() + checker.IPv4(t, b, + checker.TCP( + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagSyn), + ), + ) + + // Ensure that we've reached SynSent state + if got, want := tcp.EndpointState(c.EP.State()), tcp.StateSynSent; got != want { + t.Fatalf("got State() = %s, want %s", got, want) + } + tcpHdr := header.TCP(header.IPv4(b).Payload()) + c.IRS = seqnum.Value(tcpHdr.SequenceNumber()) + + // Send a packet with a proper ACK and a RST flag to cause the socket + // to Error and close out + iss := seqnum.Value(789) + rcvWnd := seqnum.Size(30000) + c.SendPacket(nil, &context.Headers{ + SrcPort: tcpHdr.DestinationPort(), + DstPort: tcpHdr.SourcePort(), + Flags: header.TCPFlagRst | header.TCPFlagAck, + SeqNum: iss, + AckNum: c.IRS.Add(1), + RcvWnd: rcvWnd, + TCPOpts: nil, + }) + + // Wait for receive to be notified. + select { + case <-ch: + case <-time.After(3 * time.Second): + t.Fatal("timed out waiting for packet to arrive") + } + + if _, _, err := c.EP.Read(nil); err != tcpip.ErrConnectionRefused { + t.Fatalf("got c.EP.Read(nil) = %v, want = %s", err, tcpip.ErrConnectionRefused) + } + + // Due to the RST the endpoint should be in an error state. + if got, want := tcp.EndpointState(c.EP.State()), tcp.StateError; got != want { + t.Fatalf("got State() = %s, want %s", got, want) + } +} + func TestOutOfOrderReceive(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() @@ -930,8 +1500,7 @@ func TestRstOnCloseWithUnreadDataFinConvertRst(t *testing.T) { checker.TCP( checker.DstPort(context.TestPort), checker.TCPFlags(header.TCPFlagAck|header.TCPFlagRst), - // We shouldn't consume a sequence number on RST. - checker.SeqNum(uint32(c.IRS)+1), + checker.SeqNum(uint32(c.IRS)+2), )) // The RST puts the endpoint into an error state. if got, want := tcp.EndpointState(c.EP.State()), tcp.StateError; got != want { @@ -1623,7 +2192,7 @@ func TestDelay(t *testing.T) { c.CreateConnected(789, 30000, -1 /* epRcvBuf */) - c.EP.SetSockOpt(tcpip.DelayOption(1)) + c.EP.SetSockOptInt(tcpip.DelayOption, 1) var allData []byte for i, data := range [][]byte{{0}, {1, 2, 3, 4}, {5, 6, 7}, {8, 9}, {10}, {11}} { @@ -1671,7 +2240,7 @@ func TestUndelay(t *testing.T) { c.CreateConnected(789, 30000, -1 /* epRcvBuf */) - c.EP.SetSockOpt(tcpip.DelayOption(1)) + c.EP.SetSockOptInt(tcpip.DelayOption, 1) allData := [][]byte{{0}, {1, 2, 3}} for i, data := range allData { @@ -1704,7 +2273,7 @@ func TestUndelay(t *testing.T) { // Check that we don't get the second packet yet. c.CheckNoPacketTimeout("delayed second packet transmitted", 100*time.Millisecond) - c.EP.SetSockOpt(tcpip.DelayOption(0)) + c.EP.SetSockOptInt(tcpip.DelayOption, 0) // Check that data is received. second := c.GetPacket() @@ -1741,7 +2310,7 @@ func TestMSSNotDelayed(t *testing.T) { fn func(tcpip.Endpoint) }{ {"no-op", func(tcpip.Endpoint) {}}, - {"delay", func(ep tcpip.Endpoint) { ep.SetSockOpt(tcpip.DelayOption(1)) }}, + {"delay", func(ep tcpip.Endpoint) { ep.SetSockOptInt(tcpip.DelayOption, 1) }}, {"cork", func(ep tcpip.Endpoint) { ep.SetSockOpt(tcpip.CorkOption(1)) }}, } @@ -2211,6 +2780,13 @@ loop: if tcp.EndpointState(c.EP.State()) != tcp.StateError { t.Fatalf("got EP state is not StateError") } + + if got := c.Stack().Stats().TCP.EstablishedResets.Value(); got != 1 { + t.Errorf("got stats.TCP.EstablishedResets.Value() = %v, want = 1", got) + } + if got := c.Stack().Stats().TCP.CurrentEstablished.Value(); got != 0 { + t.Errorf("got stats.TCP.CurrentEstablished.Value() = %v, want = 0", got) + } } func TestSendOnResetConnection(t *testing.T) { @@ -2905,6 +3481,13 @@ func TestReadAfterClosedState(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() + // Set TCPTimeWaitTimeout to 1 seconds so that sockets are marked closed + // after 1 second in TIME_WAIT state. + tcpTimeWaitTimeout := 1 * time.Second + if err := c.Stack().SetTransportProtocolOption(tcp.ProtocolNumber, tcpip.TCPTimeWaitTimeoutOption(tcpTimeWaitTimeout)); err != nil { + t.Fatalf("c.stack.SetTransportProtocolOption(tcp, tcpip.TCPTimeWaitTimeout(%d) failed: %s", tcpTimeWaitTimeout, err) + } + c.CreateConnected(789, 30000, -1 /* epRcvBuf */) we, ch := waiter.NewChannelEntry(nil) @@ -2912,12 +3495,12 @@ func TestReadAfterClosedState(t *testing.T) { defer c.WQ.EventUnregister(&we) if _, _, err := c.EP.Read(nil); err != tcpip.ErrWouldBlock { - t.Fatalf("got c.EP.Read(nil) = %v, want = %v", err, tcpip.ErrWouldBlock) + t.Fatalf("got c.EP.Read(nil) = %v, want = %s", err, tcpip.ErrWouldBlock) } // Shutdown immediately for write, check that we get a FIN. if err := c.EP.Shutdown(tcpip.ShutdownWrite); err != nil { - t.Fatalf("Shutdown failed: %v", err) + t.Fatalf("Shutdown failed: %s", err) } checker.IPv4(t, c.GetPacket(), @@ -2955,10 +3538,9 @@ func TestReadAfterClosedState(t *testing.T) { ), ) - // Give the stack the chance to transition to closed state. Note that since - // both the sender and receiver are now closed, we effectively skip the - // TIME-WAIT state. - time.Sleep(1 * time.Second) + // Give the stack the chance to transition to closed state from + // TIME_WAIT. + time.Sleep(tcpTimeWaitTimeout * 2) if got, want := tcp.EndpointState(c.EP.State()), tcp.StateClose; got != want { t.Errorf("Unexpected endpoint state: want %v, got %v", want, got) @@ -2975,7 +3557,7 @@ func TestReadAfterClosedState(t *testing.T) { peekBuf := make([]byte, 10) n, _, err := c.EP.Peek([][]byte{peekBuf}) if err != nil { - t.Fatalf("Peek failed: %v", err) + t.Fatalf("Peek failed: %s", err) } peekBuf = peekBuf[:n] @@ -2986,7 +3568,7 @@ func TestReadAfterClosedState(t *testing.T) { // Receive data. v, _, err := c.EP.Read(nil) if err != nil { - t.Fatalf("Read failed: %v", err) + t.Fatalf("Read failed: %s", err) } if !bytes.Equal(data, v) { @@ -2996,11 +3578,11 @@ func TestReadAfterClosedState(t *testing.T) { // Now that we drained the queue, check that functions fail with the // right error code. if _, _, err := c.EP.Read(nil); err != tcpip.ErrClosedForReceive { - t.Fatalf("got c.EP.Read(nil) = %v, want = %v", err, tcpip.ErrClosedForReceive) + t.Fatalf("got c.EP.Read(nil) = %v, want = %s", err, tcpip.ErrClosedForReceive) } if _, _, err := c.EP.Peek([][]byte{peekBuf}); err != tcpip.ErrClosedForReceive { - t.Fatalf("got c.EP.Peek(...) = %v, want = %v", err, tcpip.ErrClosedForReceive) + t.Fatalf("got c.EP.Peek(...) = %v, want = %s", err, tcpip.ErrClosedForReceive) } } @@ -3773,8 +4355,9 @@ func TestKeepalive(t *testing.T) { c.CreateConnected(789, 30000, -1 /* epRcvBuf */) + const keepAliveInterval = 10 * time.Millisecond c.EP.SetSockOpt(tcpip.KeepaliveIdleOption(10 * time.Millisecond)) - c.EP.SetSockOpt(tcpip.KeepaliveIntervalOption(10 * time.Millisecond)) + c.EP.SetSockOpt(tcpip.KeepaliveIntervalOption(keepAliveInterval)) c.EP.SetSockOpt(tcpip.KeepaliveCountOption(5)) c.EP.SetSockOpt(tcpip.KeepaliveEnabledOption(1)) @@ -3864,19 +4447,43 @@ func TestKeepalive(t *testing.T) { ) } + // Sleep for a litte over the KeepAlive interval to make sure + // the timer has time to fire after the last ACK and close the + // close the socket. + time.Sleep(keepAliveInterval + 5*time.Millisecond) + // The connection should be terminated after 5 unacked keepalives. + // Send an ACK to trigger a RST from the stack as the endpoint should + // be dead. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: c.Port, + Flags: header.TCPFlagAck, + SeqNum: 790, + AckNum: seqnum.Value(next), + RcvWnd: 30000, + }) + checker.IPv4(t, c.GetPacket(), checker.TCP( checker.DstPort(context.TestPort), checker.SeqNum(uint32(next)), - checker.AckNum(uint32(790)), - checker.TCPFlags(header.TCPFlagAck|header.TCPFlagRst), + checker.AckNum(uint32(0)), + checker.TCPFlags(header.TCPFlagRst), ), ) + if got := c.Stack().Stats().TCP.EstablishedTimedout.Value(); got != 1 { + t.Errorf("got c.Stack().Stats().TCP.EstablishedTimedout.Value() = %v, want = 1", got) + } + if _, _, err := c.EP.Read(nil); err != tcpip.ErrTimeout { t.Fatalf("got c.EP.Read(nil) = %v, want = %v", err, tcpip.ErrTimeout) } + + if got := c.Stack().Stats().TCP.CurrentEstablished.Value(); got != 0 { + t.Errorf("got stats.TCP.CurrentEstablished.Value() = %v, want = 0", got) + } } func executeHandshake(t *testing.T, c *context.Context, srcPort uint16, synCookieInUse bool) (irs, iss seqnum.Value) { @@ -3890,7 +4497,7 @@ func executeHandshake(t *testing.T, c *context.Context, srcPort uint16, synCooki RcvWnd: 30000, }) - // Receive the SYN-ACK reply.w + // Receive the SYN-ACK reply. b := c.GetPacket() tcp := header.TCP(header.IPv4(b).Payload()) iss = seqnum.Value(tcp.SequenceNumber()) @@ -3923,6 +4530,50 @@ func executeHandshake(t *testing.T, c *context.Context, srcPort uint16, synCooki return irs, iss } +func executeV6Handshake(t *testing.T, c *context.Context, srcPort uint16, synCookieInUse bool) (irs, iss seqnum.Value) { + // Send a SYN request. + irs = seqnum.Value(789) + c.SendV6Packet(nil, &context.Headers{ + SrcPort: srcPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: irs, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b := c.GetV6Packet() + tcp := header.TCP(header.IPv6(b).Payload()) + iss = seqnum.Value(tcp.SequenceNumber()) + tcpCheckers := []checker.TransportChecker{ + checker.SrcPort(context.StackPort), + checker.DstPort(srcPort), + checker.TCPFlags(header.TCPFlagAck | header.TCPFlagSyn), + checker.AckNum(uint32(irs) + 1), + } + + if synCookieInUse { + // When cookies are in use window scaling is disabled. + tcpCheckers = append(tcpCheckers, checker.TCPSynOptions(header.TCPSynOptions{ + WS: -1, + MSS: c.MSSWithoutOptionsV6(), + })) + } + + checker.IPv6(t, b, checker.TCP(tcpCheckers...)) + + // Send ACK. + c.SendV6Packet(nil, &context.Headers{ + SrcPort: srcPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: irs + 1, + AckNum: iss + 1, + RcvWnd: 30000, + }) + return irs, iss +} + // TestListenBacklogFull tests that netstack does not complete handshakes if the // listen backlog for the endpoint is full. func TestListenBacklogFull(t *testing.T) { @@ -4025,6 +4676,210 @@ func TestListenBacklogFull(t *testing.T) { } } +// TestListenNoAcceptMulticastBroadcastV4 makes sure that TCP segments with a +// non unicast IPv4 address are not accepted. +func TestListenNoAcceptNonUnicastV4(t *testing.T) { + multicastAddr := tcpip.Address("\xe0\x00\x01\x02") + otherMulticastAddr := tcpip.Address("\xe0\x00\x01\x03") + + tests := []struct { + name string + srcAddr tcpip.Address + dstAddr tcpip.Address + }{ + { + "SourceUnspecified", + header.IPv4Any, + context.StackAddr, + }, + { + "SourceBroadcast", + header.IPv4Broadcast, + context.StackAddr, + }, + { + "SourceOurMulticast", + multicastAddr, + context.StackAddr, + }, + { + "SourceOtherMulticast", + otherMulticastAddr, + context.StackAddr, + }, + { + "DestUnspecified", + context.TestAddr, + header.IPv4Any, + }, + { + "DestBroadcast", + context.TestAddr, + header.IPv4Broadcast, + }, + { + "DestOurMulticast", + context.TestAddr, + multicastAddr, + }, + { + "DestOtherMulticast", + context.TestAddr, + otherMulticastAddr, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + t.Parallel() + + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.Create(-1) + + if err := c.Stack().JoinGroup(header.IPv4ProtocolNumber, 1, multicastAddr); err != nil { + t.Fatalf("JoinGroup failed: %s", err) + } + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + if err := c.EP.Listen(1); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + irs := seqnum.Value(789) + c.SendPacketWithAddrs(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: irs, + RcvWnd: 30000, + }, test.srcAddr, test.dstAddr) + c.CheckNoPacket("Should not have received a response") + + // Handle normal packet. + c.SendPacketWithAddrs(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: irs, + RcvWnd: 30000, + }, context.TestAddr, context.StackAddr) + checker.IPv4(t, c.GetPacket(), + checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagAck|header.TCPFlagSyn), + checker.AckNum(uint32(irs)+1))) + }) + } +} + +// TestListenNoAcceptMulticastBroadcastV6 makes sure that TCP segments with a +// non unicast IPv6 address are not accepted. +func TestListenNoAcceptNonUnicastV6(t *testing.T) { + multicastAddr := tcpip.Address("\xff\x0e\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x01") + otherMulticastAddr := tcpip.Address("\xff\x0e\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x02") + + tests := []struct { + name string + srcAddr tcpip.Address + dstAddr tcpip.Address + }{ + { + "SourceUnspecified", + header.IPv6Any, + context.StackV6Addr, + }, + { + "SourceAllNodes", + header.IPv6AllNodesMulticastAddress, + context.StackV6Addr, + }, + { + "SourceOurMulticast", + multicastAddr, + context.StackV6Addr, + }, + { + "SourceOtherMulticast", + otherMulticastAddr, + context.StackV6Addr, + }, + { + "DestUnspecified", + context.TestV6Addr, + header.IPv6Any, + }, + { + "DestAllNodes", + context.TestV6Addr, + header.IPv6AllNodesMulticastAddress, + }, + { + "DestOurMulticast", + context.TestV6Addr, + multicastAddr, + }, + { + "DestOtherMulticast", + context.TestV6Addr, + otherMulticastAddr, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + t.Parallel() + + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.CreateV6Endpoint(true) + + if err := c.Stack().JoinGroup(header.IPv6ProtocolNumber, 1, multicastAddr); err != nil { + t.Fatalf("JoinGroup failed: %s", err) + } + + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + if err := c.EP.Listen(1); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + irs := seqnum.Value(789) + c.SendV6PacketWithAddrs(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: irs, + RcvWnd: 30000, + }, test.srcAddr, test.dstAddr) + c.CheckNoPacket("Should not have received a response") + + // Handle normal packet. + c.SendV6PacketWithAddrs(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: irs, + RcvWnd: 30000, + }, context.TestV6Addr, context.StackV6Addr) + checker.IPv6(t, c.GetV6Packet(), + checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagAck|header.TCPFlagSyn), + checker.AckNum(uint32(irs)+1))) + }) + } +} + func TestListenSynRcvdQueueFull(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() @@ -4056,7 +4911,7 @@ func TestListenSynRcvdQueueFull(t *testing.T) { SrcPort: context.TestPort, DstPort: context.StackPort, Flags: header.TCPFlagSyn, - SeqNum: seqnum.Value(789), + SeqNum: irs, RcvWnd: 30000, }) @@ -4167,7 +5022,8 @@ func TestListenBacklogFullSynCookieInUse(t *testing.T) { // Send a SYN request. irs := seqnum.Value(789) c.SendPacket(nil, &context.Headers{ - SrcPort: context.TestPort, + // pick a different src port for new SYN. + SrcPort: context.TestPort + 1, DstPort: context.StackPort, Flags: header.TCPFlagSyn, SeqNum: irs, @@ -4207,6 +5063,125 @@ func TestListenBacklogFullSynCookieInUse(t *testing.T) { } } +func TestSynRcvdBadSeqNumber(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + // Create TCP endpoint. + var err *tcpip.Error + c.EP, err = c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, &c.WQ) + if err != nil { + t.Fatalf("NewEndpoint failed: %s", err) + } + + // Bind to wildcard. + if err := c.EP.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + // Start listening. + if err := c.EP.Listen(10); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + // Send a SYN to get a SYN-ACK. This should put the ep into SYN-RCVD state + irs := seqnum.Value(789) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: irs, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b := c.GetPacket() + tcpHdr := header.TCP(header.IPv4(b).Payload()) + iss := seqnum.Value(tcpHdr.SequenceNumber()) + tcpCheckers := []checker.TransportChecker{ + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagAck | header.TCPFlagSyn), + checker.AckNum(uint32(irs) + 1), + } + checker.IPv4(t, b, checker.TCP(tcpCheckers...)) + + // Now send a packet with an out-of-window sequence number + largeSeqnum := irs + seqnum.Value(tcpHdr.WindowSize()) + 1 + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: largeSeqnum, + AckNum: iss + 1, + RcvWnd: 30000, + }) + + // Should receive an ACK with the expected SEQ number + b = c.GetPacket() + tcpCheckers = []checker.TransportChecker{ + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.TCPFlags(header.TCPFlagAck), + checker.AckNum(uint32(irs) + 1), + checker.SeqNum(uint32(iss + 1)), + } + checker.IPv4(t, b, checker.TCP(tcpCheckers...)) + + // Now that the socket replied appropriately with the ACK, + // complete the connection to test that the large SEQ num + // did not change the state from SYN-RCVD. + + // Send ACK to move to ESTABLISHED state. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: irs + 1, + AckNum: iss + 1, + RcvWnd: 30000, + }) + + newEP, _, err := c.EP.Accept() + + if err != nil && err != tcpip.ErrWouldBlock { + t.Fatalf("Accept failed: %s", err) + } + + if err == tcpip.ErrWouldBlock { + // Try to accept the connections in the backlog. + we, ch := waiter.NewChannelEntry(nil) + c.WQ.EventRegister(&we, waiter.EventIn) + defer c.WQ.EventUnregister(&we) + + // Wait for connection to be established. + select { + case <-ch: + newEP, _, err = c.EP.Accept() + if err != nil { + t.Fatalf("Accept failed: %s", err) + } + + case <-time.After(1 * time.Second): + t.Fatalf("Timed out waiting for accept") + } + } + + // Now verify that the TCP socket is usable and in a connected state. + data := "Don't panic" + _, _, err = newEP.Write(tcpip.SlicePayload(buffer.NewViewFromBytes([]byte(data))), tcpip.WriteOptions{}) + + if err != nil { + t.Fatalf("Write failed: %s", err) + } + + pkt := c.GetPacket() + tcpHdr = header.TCP(header.IPv4(pkt).Payload()) + if string(tcpHdr.Payload()) != data { + t.Fatalf("Unexpected data: got %s, want %s", string(tcpHdr.Payload()), data) + } +} + func TestPassiveConnectionAttemptIncrement(t *testing.T) { c := context.New(t, defaultMTU) defer c.Cleanup() @@ -4381,6 +5356,9 @@ func TestEndpointBindListenAcceptState(t *testing.T) { if got, want := tcp.EndpointState(aep.State()), tcp.StateEstablished; got != want { t.Errorf("Unexpected endpoint state: want %v, got %v", want, got) } + if err := aep.Connect(tcpip.FullAddress{Addr: context.TestAddr, Port: context.TestPort}); err != tcpip.ErrAlreadyConnected { + t.Errorf("Unexpected error attempting to call connect on an established endpoint, got: %v, want: %v", err, tcpip.ErrAlreadyConnected) + } // Listening endpoint remains in listen state. if got, want := tcp.EndpointState(ep.State()), tcp.StateListen; got != want { t.Errorf("Unexpected endpoint state: want %v, got %v", want, got) @@ -4668,3 +5646,918 @@ func TestReceiveBufferAutoTuning(t *testing.T) { payloadSize *= 2 } } + +func TestDelayEnabled(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + checkDelayOption(t, c, false, 0) // Delay is disabled by default. + + for _, v := range []struct { + delayEnabled tcp.DelayEnabled + wantDelayOption int + }{ + {delayEnabled: false, wantDelayOption: 0}, + {delayEnabled: true, wantDelayOption: 1}, + } { + c := context.New(t, defaultMTU) + defer c.Cleanup() + if err := c.Stack().SetTransportProtocolOption(tcp.ProtocolNumber, v.delayEnabled); err != nil { + t.Fatalf("SetTransportProtocolOption(tcp, %t) failed: %v", v.delayEnabled, err) + } + checkDelayOption(t, c, v.delayEnabled, v.wantDelayOption) + } +} + +func checkDelayOption(t *testing.T, c *context.Context, wantDelayEnabled tcp.DelayEnabled, wantDelayOption int) { + t.Helper() + + var gotDelayEnabled tcp.DelayEnabled + if err := c.Stack().TransportProtocolOption(tcp.ProtocolNumber, &gotDelayEnabled); err != nil { + t.Fatalf("TransportProtocolOption(tcp, &gotDelayEnabled) failed: %v", err) + } + if gotDelayEnabled != wantDelayEnabled { + t.Errorf("TransportProtocolOption(tcp, &gotDelayEnabled) got %t, want %t", gotDelayEnabled, wantDelayEnabled) + } + + ep, err := c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, new(waiter.Queue)) + if err != nil { + t.Fatalf("NewEndPoint(tcp, ipv4, new(waiter.Queue)) failed: %v", err) + } + gotDelayOption, err := ep.GetSockOptInt(tcpip.DelayOption) + if err != nil { + t.Fatalf("ep.GetSockOptInt(tcpip.DelayOption) failed: %v", err) + } + if gotDelayOption != wantDelayOption { + t.Errorf("ep.GetSockOptInt(tcpip.DelayOption) got: %d, want: %d", gotDelayOption, wantDelayOption) + } +} + +func TestTCPLingerTimeout(t *testing.T) { + c := context.New(t, 1500 /* mtu */) + defer c.Cleanup() + + c.CreateConnected(789, 30000, -1 /* epRcvBuf */) + + testCases := []struct { + name string + tcpLingerTimeout time.Duration + want time.Duration + }{ + {"NegativeLingerTimeout", -123123, 0}, + {"ZeroLingerTimeout", 0, 0}, + {"InRangeLingerTimeout", 10 * time.Second, 10 * time.Second}, + // Values > stack's TCPLingerTimeout are capped to the stack's + // value. Defaults to tcp.DefaultTCPLingerTimeout(60 seconds) + {"AboveMaxLingerTimeout", 65 * time.Second, 60 * time.Second}, + } + for _, tc := range testCases { + t.Run(tc.name, func(t *testing.T) { + if err := c.EP.SetSockOpt(tcpip.TCPLingerTimeoutOption(tc.tcpLingerTimeout)); err != nil { + t.Fatalf("SetSockOpt(%s) = %s", tc.tcpLingerTimeout, err) + } + var v tcpip.TCPLingerTimeoutOption + if err := c.EP.GetSockOpt(&v); err != nil { + t.Fatalf("GetSockOpt(tcpip.TCPLingerTimeoutOption) = %s", err) + } + if got, want := time.Duration(v), tc.want; got != want { + t.Fatalf("unexpected linger timeout got: %s, want: %s", got, want) + } + }) + } +} + +func TestTCPTimeWaitRSTIgnored(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + wq := &waiter.Queue{} + ep, err := c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, wq) + if err != nil { + t.Fatalf("NewEndpoint failed: %s", err) + } + if err := ep.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + if err := ep.Listen(10); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + // Send a SYN request. + iss := seqnum.Value(789) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: iss, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b := c.GetPacket() + tcpHdr := header.TCP(header.IPv4(b).Payload()) + c.IRS = seqnum.Value(tcpHdr.SequenceNumber()) + + ackHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 1, + } + + // Send ACK. + c.SendPacket(nil, ackHeaders) + + // Try to accept the connection. + we, ch := waiter.NewChannelEntry(nil) + wq.EventRegister(&we, waiter.EventIn) + defer wq.EventUnregister(&we) + + c.EP, _, err = ep.Accept() + if err == tcpip.ErrWouldBlock { + // Wait for connection to be established. + select { + case <-ch: + c.EP, _, err = ep.Accept() + if err != nil { + t.Fatalf("Accept failed: %s", err) + } + + case <-time.After(1 * time.Second): + t.Fatalf("Timed out waiting for accept") + } + } + + c.EP.Close() + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+1)), + checker.AckNum(uint32(iss)+1), + checker.TCPFlags(header.TCPFlagFin|header.TCPFlagAck))) + + finHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck | header.TCPFlagFin, + SeqNum: iss + 1, + AckNum: c.IRS + 2, + } + + c.SendPacket(nil, finHeaders) + + // Get the ACK to the FIN we just sent. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+2)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) + + // Now send a RST and this should be ignored and not + // generate an ACK. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagRst, + SeqNum: iss + 1, + AckNum: c.IRS + 2, + }) + + c.CheckNoPacketTimeout("unexpected packet received in TIME_WAIT state", 1*time.Second) + + // Out of order ACK should generate an immediate ACK in + // TIME_WAIT. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 3, + }) + + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+2)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) +} + +func TestTCPTimeWaitOutOfOrder(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + wq := &waiter.Queue{} + ep, err := c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, wq) + if err != nil { + t.Fatalf("NewEndpoint failed: %s", err) + } + if err := ep.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + if err := ep.Listen(10); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + // Send a SYN request. + iss := seqnum.Value(789) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: iss, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b := c.GetPacket() + tcpHdr := header.TCP(header.IPv4(b).Payload()) + c.IRS = seqnum.Value(tcpHdr.SequenceNumber()) + + ackHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 1, + } + + // Send ACK. + c.SendPacket(nil, ackHeaders) + + // Try to accept the connection. + we, ch := waiter.NewChannelEntry(nil) + wq.EventRegister(&we, waiter.EventIn) + defer wq.EventUnregister(&we) + + c.EP, _, err = ep.Accept() + if err == tcpip.ErrWouldBlock { + // Wait for connection to be established. + select { + case <-ch: + c.EP, _, err = ep.Accept() + if err != nil { + t.Fatalf("Accept failed: %s", err) + } + + case <-time.After(1 * time.Second): + t.Fatalf("Timed out waiting for accept") + } + } + + c.EP.Close() + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+1)), + checker.AckNum(uint32(iss)+1), + checker.TCPFlags(header.TCPFlagFin|header.TCPFlagAck))) + + finHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck | header.TCPFlagFin, + SeqNum: iss + 1, + AckNum: c.IRS + 2, + } + + c.SendPacket(nil, finHeaders) + + // Get the ACK to the FIN we just sent. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+2)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) + + // Out of order ACK should generate an immediate ACK in + // TIME_WAIT. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 3, + }) + + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+2)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) +} + +func TestTCPTimeWaitNewSyn(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + wq := &waiter.Queue{} + ep, err := c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, wq) + if err != nil { + t.Fatalf("NewEndpoint failed: %s", err) + } + if err := ep.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + if err := ep.Listen(10); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + // Send a SYN request. + iss := seqnum.Value(789) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: iss, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b := c.GetPacket() + tcpHdr := header.TCP(header.IPv4(b).Payload()) + c.IRS = seqnum.Value(tcpHdr.SequenceNumber()) + + ackHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 1, + } + + // Send ACK. + c.SendPacket(nil, ackHeaders) + + // Try to accept the connection. + we, ch := waiter.NewChannelEntry(nil) + wq.EventRegister(&we, waiter.EventIn) + defer wq.EventUnregister(&we) + + c.EP, _, err = ep.Accept() + if err == tcpip.ErrWouldBlock { + // Wait for connection to be established. + select { + case <-ch: + c.EP, _, err = ep.Accept() + if err != nil { + t.Fatalf("Accept failed: %s", err) + } + + case <-time.After(1 * time.Second): + t.Fatalf("Timed out waiting for accept") + } + } + + c.EP.Close() + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+1)), + checker.AckNum(uint32(iss)+1), + checker.TCPFlags(header.TCPFlagFin|header.TCPFlagAck))) + + finHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck | header.TCPFlagFin, + SeqNum: iss + 1, + AckNum: c.IRS + 2, + } + + c.SendPacket(nil, finHeaders) + + // Get the ACK to the FIN we just sent. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+2)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) + + // Send a SYN request w/ sequence number lower than + // the highest sequence number sent. We just reuse + // the same number. + iss = seqnum.Value(789) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: iss, + RcvWnd: 30000, + }) + + c.CheckNoPacketTimeout("unexpected packet received in response to SYN", 1*time.Second) + + // Send a SYN request w/ sequence number higher than + // the highest sequence number sent. + iss = seqnum.Value(792) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: iss, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b = c.GetPacket() + tcpHdr = header.TCP(header.IPv4(b).Payload()) + c.IRS = seqnum.Value(tcpHdr.SequenceNumber()) + + ackHeaders = &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 1, + } + + // Send ACK. + c.SendPacket(nil, ackHeaders) + + // Try to accept the connection. + c.EP, _, err = ep.Accept() + if err == tcpip.ErrWouldBlock { + // Wait for connection to be established. + select { + case <-ch: + c.EP, _, err = ep.Accept() + if err != nil { + t.Fatalf("Accept failed: %s", err) + } + + case <-time.After(1 * time.Second): + t.Fatalf("Timed out waiting for accept") + } + } +} + +func TestTCPTimeWaitDuplicateFINExtendsTimeWait(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + // Set TCPTimeWaitTimeout to 5 seconds so that sockets are marked closed + // after 5 seconds in TIME_WAIT state. + tcpTimeWaitTimeout := 5 * time.Second + if err := c.Stack().SetTransportProtocolOption(tcp.ProtocolNumber, tcpip.TCPTimeWaitTimeoutOption(tcpTimeWaitTimeout)); err != nil { + t.Fatalf("c.stack.SetTransportProtocolOption(tcp, tcpip.TCPLingerTimeoutOption(%d) failed: %s", tcpTimeWaitTimeout, err) + } + + want := c.Stack().Stats().TCP.EstablishedClosed.Value() + 1 + + wq := &waiter.Queue{} + ep, err := c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, wq) + if err != nil { + t.Fatalf("NewEndpoint failed: %s", err) + } + if err := ep.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + if err := ep.Listen(10); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + // Send a SYN request. + iss := seqnum.Value(789) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: iss, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b := c.GetPacket() + tcpHdr := header.TCP(header.IPv4(b).Payload()) + c.IRS = seqnum.Value(tcpHdr.SequenceNumber()) + + ackHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 1, + } + + // Send ACK. + c.SendPacket(nil, ackHeaders) + + // Try to accept the connection. + we, ch := waiter.NewChannelEntry(nil) + wq.EventRegister(&we, waiter.EventIn) + defer wq.EventUnregister(&we) + + c.EP, _, err = ep.Accept() + if err == tcpip.ErrWouldBlock { + // Wait for connection to be established. + select { + case <-ch: + c.EP, _, err = ep.Accept() + if err != nil { + t.Fatalf("Accept failed: %s", err) + } + + case <-time.After(1 * time.Second): + t.Fatalf("Timed out waiting for accept") + } + } + + c.EP.Close() + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+1)), + checker.AckNum(uint32(iss)+1), + checker.TCPFlags(header.TCPFlagFin|header.TCPFlagAck))) + + finHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck | header.TCPFlagFin, + SeqNum: iss + 1, + AckNum: c.IRS + 2, + } + + c.SendPacket(nil, finHeaders) + + // Get the ACK to the FIN we just sent. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+2)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) + + time.Sleep(2 * time.Second) + + // Now send a duplicate FIN. This should cause the TIME_WAIT to extend + // by another 5 seconds and also send us a duplicate ACK as it should + // indicate that the final ACK was potentially lost. + c.SendPacket(nil, finHeaders) + + // Get the ACK to the FIN we just sent. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+2)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) + + // Sleep for 4 seconds so at this point we are 1 second past the + // original tcpLingerTimeout of 5 seconds. + time.Sleep(4 * time.Second) + + // Send an ACK and it should not generate any packet as the socket + // should still be in TIME_WAIT for another another 5 seconds due + // to the duplicate FIN we sent earlier. + *ackHeaders = *finHeaders + ackHeaders.SeqNum = ackHeaders.SeqNum + 1 + ackHeaders.Flags = header.TCPFlagAck + c.SendPacket(nil, ackHeaders) + + c.CheckNoPacketTimeout("unexpected packet received from endpoint in TIME_WAIT", 1*time.Second) + // Now sleep for another 2 seconds so that we are past the + // extended TIME_WAIT of 7 seconds (2 + 5). + time.Sleep(2 * time.Second) + + // Resend the same ACK. + c.SendPacket(nil, ackHeaders) + + // Receive the RST that should be generated as there is no valid + // endpoint. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(ackHeaders.AckNum)), + checker.AckNum(0), + checker.TCPFlags(header.TCPFlagRst))) + + if got := c.Stack().Stats().TCP.EstablishedClosed.Value(); got != want { + t.Errorf("got c.Stack().Stats().TCP.EstablishedClosed = %v, want = %v", got, want) + } + if got := c.Stack().Stats().TCP.CurrentEstablished.Value(); got != 0 { + t.Errorf("got stats.TCP.CurrentEstablished.Value() = %v, want = 0", got) + } +} + +func TestTCPCloseWithData(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + // Set TCPTimeWaitTimeout to 5 seconds so that sockets are marked closed + // after 5 seconds in TIME_WAIT state. + tcpTimeWaitTimeout := 5 * time.Second + if err := c.Stack().SetTransportProtocolOption(tcp.ProtocolNumber, tcpip.TCPTimeWaitTimeoutOption(tcpTimeWaitTimeout)); err != nil { + t.Fatalf("c.stack.SetTransportProtocolOption(tcp, tcpip.TCPLingerTimeoutOption(%d) failed: %s", tcpTimeWaitTimeout, err) + } + + wq := &waiter.Queue{} + ep, err := c.Stack().NewEndpoint(tcp.ProtocolNumber, ipv4.ProtocolNumber, wq) + if err != nil { + t.Fatalf("NewEndpoint failed: %s", err) + } + if err := ep.Bind(tcpip.FullAddress{Port: context.StackPort}); err != nil { + t.Fatalf("Bind failed: %s", err) + } + + if err := ep.Listen(10); err != nil { + t.Fatalf("Listen failed: %s", err) + } + + // Send a SYN request. + iss := seqnum.Value(789) + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagSyn, + SeqNum: iss, + RcvWnd: 30000, + }) + + // Receive the SYN-ACK reply. + b := c.GetPacket() + tcpHdr := header.TCP(header.IPv4(b).Payload()) + c.IRS = seqnum.Value(tcpHdr.SequenceNumber()) + + ackHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 1, + AckNum: c.IRS + 1, + RcvWnd: 30000, + } + + // Send ACK. + c.SendPacket(nil, ackHeaders) + + // Try to accept the connection. + we, ch := waiter.NewChannelEntry(nil) + wq.EventRegister(&we, waiter.EventIn) + defer wq.EventUnregister(&we) + + c.EP, _, err = ep.Accept() + if err == tcpip.ErrWouldBlock { + // Wait for connection to be established. + select { + case <-ch: + c.EP, _, err = ep.Accept() + if err != nil { + t.Fatalf("Accept failed: %s", err) + } + + case <-time.After(1 * time.Second): + t.Fatalf("Timed out waiting for accept") + } + } + + // Now trigger a passive close by sending a FIN. + finHeaders := &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck | header.TCPFlagFin, + SeqNum: iss + 1, + AckNum: c.IRS + 2, + RcvWnd: 30000, + } + + c.SendPacket(nil, finHeaders) + + // Get the ACK to the FIN we just sent. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+1)), + checker.AckNum(uint32(iss)+2), + checker.TCPFlags(header.TCPFlagAck))) + + // Now write a few bytes and then close the endpoint. + data := []byte{1, 2, 3} + view := buffer.NewView(len(data)) + copy(view, data) + + if _, _, err := c.EP.Write(tcpip.SlicePayload(view), tcpip.WriteOptions{}); err != nil { + t.Fatalf("Write failed: %s", err) + } + + // Check that data is received. + b = c.GetPacket() + checker.IPv4(t, b, + checker.PayloadLen(len(data)+header.TCPMinimumSize), + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS)+1), + checker.AckNum(uint32(iss)+2), // Acknum is initial sequence number + 1 + checker.TCPFlagsMatch(header.TCPFlagAck, ^uint8(header.TCPFlagPsh)), + ), + ) + + if p := b[header.IPv4MinimumSize+header.TCPMinimumSize:]; !bytes.Equal(data, p) { + t.Errorf("got data = %x, want = %x", p, data) + } + + c.EP.Close() + // Check the FIN. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+1)+uint32(len(data))), + checker.AckNum(uint32(iss+2)), + checker.TCPFlags(header.TCPFlagFin|header.TCPFlagAck))) + + // First send a partial ACK. + ackHeaders = &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 2, + AckNum: c.IRS + 1 + seqnum.Value(len(data)-1), + RcvWnd: 30000, + } + c.SendPacket(nil, ackHeaders) + + // Now send a full ACK. + ackHeaders = &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 2, + AckNum: c.IRS + 1 + seqnum.Value(len(data)), + RcvWnd: 30000, + } + c.SendPacket(nil, ackHeaders) + + // Now ACK the FIN. + ackHeaders.AckNum++ + c.SendPacket(nil, ackHeaders) + + // Now send an ACK and we should get a RST back as the endpoint should + // be in CLOSED state. + ackHeaders = &context.Headers{ + SrcPort: context.TestPort, + DstPort: context.StackPort, + Flags: header.TCPFlagAck, + SeqNum: iss + 2, + AckNum: c.IRS + 1 + seqnum.Value(len(data)), + RcvWnd: 30000, + } + c.SendPacket(nil, ackHeaders) + + // Check the RST. + checker.IPv4(t, c.GetPacket(), checker.TCP( + checker.SrcPort(context.StackPort), + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(ackHeaders.AckNum)), + checker.AckNum(0), + checker.TCPFlags(header.TCPFlagRst))) +} + +func TestTCPUserTimeout(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.CreateConnected(789, 30000, -1 /* epRcvBuf */) + + origEstablishedTimedout := c.Stack().Stats().TCP.EstablishedTimedout.Value() + + userTimeout := 50 * time.Millisecond + c.EP.SetSockOpt(tcpip.TCPUserTimeoutOption(userTimeout)) + + // Send some data and wait before ACKing it. + view := buffer.NewView(3) + if _, _, err := c.EP.Write(tcpip.SlicePayload(view), tcpip.WriteOptions{}); err != nil { + t.Fatalf("Write failed: %v", err) + } + + next := uint32(c.IRS) + 1 + checker.IPv4(t, c.GetPacket(), + checker.PayloadLen(len(view)+header.TCPMinimumSize), + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(next), + checker.AckNum(790), + checker.TCPFlagsMatch(header.TCPFlagAck, ^uint8(header.TCPFlagPsh)), + ), + ) + + // Wait for a little over the minimum retransmit timeout of 200ms for + // the retransmitTimer to fire and close the connection. + time.Sleep(tcp.MinRTO + 10*time.Millisecond) + + // No packet should be received as the connection should be silently + // closed due to timeout. + c.CheckNoPacket("unexpected packet received after userTimeout has expired") + + next += uint32(len(view)) + + // The connection should be terminated after userTimeout has expired. + // Send an ACK to trigger a RST from the stack as the endpoint should + // be dead. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: c.Port, + Flags: header.TCPFlagAck, + SeqNum: 790, + AckNum: seqnum.Value(next), + RcvWnd: 30000, + }) + + checker.IPv4(t, c.GetPacket(), + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(next)), + checker.AckNum(uint32(0)), + checker.TCPFlags(header.TCPFlagRst), + ), + ) + + if _, _, err := c.EP.Read(nil); err != tcpip.ErrTimeout { + t.Fatalf("got c.EP.Read(nil) = %v, want = %v", err, tcpip.ErrTimeout) + } + + if got, want := c.Stack().Stats().TCP.EstablishedTimedout.Value(), origEstablishedTimedout+1; got != want { + t.Errorf("got c.Stack().Stats().TCP.EstablishedTimedout = %v, want = %v", got, want) + } +} + +func TestKeepaliveWithUserTimeout(t *testing.T) { + c := context.New(t, defaultMTU) + defer c.Cleanup() + + c.CreateConnected(789, 30000, -1 /* epRcvBuf */) + + origEstablishedTimedout := c.Stack().Stats().TCP.EstablishedTimedout.Value() + + const keepAliveInterval = 10 * time.Millisecond + c.EP.SetSockOpt(tcpip.KeepaliveIdleOption(10 * time.Millisecond)) + c.EP.SetSockOpt(tcpip.KeepaliveIntervalOption(keepAliveInterval)) + c.EP.SetSockOpt(tcpip.KeepaliveCountOption(10)) + c.EP.SetSockOpt(tcpip.KeepaliveEnabledOption(1)) + + // Set userTimeout to be the duration for 3 keepalive probes. + userTimeout := 30 * time.Millisecond + c.EP.SetSockOpt(tcpip.TCPUserTimeoutOption(userTimeout)) + + // Check that the connection is still alive. + if _, _, err := c.EP.Read(nil); err != tcpip.ErrWouldBlock { + t.Fatalf("got c.EP.Read(nil) = %v, want = %v", err, tcpip.ErrWouldBlock) + } + + // Now receive 2 keepalives, but don't ACK them. The connection should + // be reset when the 3rd one should be sent due to userTimeout being + // 30ms and each keepalive probe should be sent 10ms apart as set above after + // the connection has been idle for 10ms. + for i := 0; i < 2; i++ { + b := c.GetPacket() + checker.IPv4(t, b, + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS)), + checker.AckNum(uint32(790)), + checker.TCPFlags(header.TCPFlagAck), + ), + ) + } + + // Sleep for a litte over the KeepAlive interval to make sure + // the timer has time to fire after the last ACK and close the + // close the socket. + time.Sleep(keepAliveInterval + 5*time.Millisecond) + + // The connection should be terminated after 30ms. + // Send an ACK to trigger a RST from the stack as the endpoint should + // be dead. + c.SendPacket(nil, &context.Headers{ + SrcPort: context.TestPort, + DstPort: c.Port, + Flags: header.TCPFlagAck, + SeqNum: 790, + AckNum: seqnum.Value(c.IRS + 1), + RcvWnd: 30000, + }) + + checker.IPv4(t, c.GetPacket(), + checker.TCP( + checker.DstPort(context.TestPort), + checker.SeqNum(uint32(c.IRS+1)), + checker.AckNum(uint32(0)), + checker.TCPFlags(header.TCPFlagRst), + ), + ) + + if _, _, err := c.EP.Read(nil); err != tcpip.ErrTimeout { + t.Fatalf("got c.EP.Read(nil) = %v, want = %v", err, tcpip.ErrTimeout) + } + if got, want := c.Stack().Stats().TCP.EstablishedTimedout.Value(), origEstablishedTimedout+1; got != want { + t.Errorf("got c.Stack().Stats().TCP.EstablishedTimedout = %v, want = %v", got, want) + } +} diff --git a/pkg/tcpip/transport/tcp/testing/context/BUILD b/pkg/tcpip/transport/tcp/testing/context/BUILD index 19b0d31c5..b33ec2087 100644 --- a/pkg/tcpip/transport/tcp/testing/context/BUILD +++ b/pkg/tcpip/transport/tcp/testing/context/BUILD @@ -8,7 +8,7 @@ go_library( srcs = ["context.go"], importpath = "gvisor.dev/gvisor/pkg/tcpip/transport/tcp/testing/context", visibility = [ - "//:sandbox", + "//visibility:public", ], deps = [ "//pkg/tcpip", diff --git a/pkg/tcpip/transport/tcp/testing/context/context.go b/pkg/tcpip/transport/tcp/testing/context/context.go index ef823e4ae..b0a376eba 100644 --- a/pkg/tcpip/transport/tcp/testing/context/context.go +++ b/pkg/tcpip/transport/tcp/testing/context/context.go @@ -231,14 +231,15 @@ func (c *Context) CheckNoPacket(errMsg string) { // addresses. It will fail with an error if no packet is received for // 2 seconds. func (c *Context) GetPacket() []byte { + c.t.Helper() select { case p := <-c.linkEP.C: if p.Proto != ipv4.ProtocolNumber { c.t.Fatalf("Bad network protocol: got %v, wanted %v", p.Proto, ipv4.ProtocolNumber) } - b := make([]byte, len(p.Header)+len(p.Payload)) - copy(b, p.Header) - copy(b[len(p.Header):], p.Payload) + + hdr := p.Pkt.Header.View() + b := append(hdr[:len(hdr):len(hdr)], p.Pkt.Data.ToView()...) if p.GSO != nil && p.GSO.L3HdrLen != header.IPv4MinimumSize { c.t.Errorf("L3HdrLen %v (expected %v)", p.GSO.L3HdrLen, header.IPv4MinimumSize) @@ -259,14 +260,15 @@ func (c *Context) GetPacket() []byte { // and destination address. If no packet is available it will return // nil immediately. func (c *Context) GetPacketNonBlocking() []byte { + c.t.Helper() select { case p := <-c.linkEP.C: if p.Proto != ipv4.ProtocolNumber { c.t.Fatalf("Bad network protocol: got %v, wanted %v", p.Proto, ipv4.ProtocolNumber) } - b := make([]byte, len(p.Header)+len(p.Payload)) - copy(b, p.Header) - copy(b[len(p.Header):], p.Payload) + + hdr := p.Pkt.Header.View() + b := append(hdr[:len(hdr):len(hdr)], p.Pkt.Data.ToView()...) checker.IPv4(c.t, b, checker.SrcAddr(StackAddr), checker.DstAddr(TestAddr)) return b @@ -302,11 +304,19 @@ func (c *Context) SendICMPPacket(typ header.ICMPv4Type, code uint8, p1, p2 []byt copy(icmp[header.ICMPv4PayloadOffset:], p2) // Inject packet. - c.linkEP.Inject(ipv4.ProtocolNumber, buf.ToVectorisedView()) + c.linkEP.InjectInbound(ipv4.ProtocolNumber, tcpip.PacketBuffer{ + Data: buf.ToVectorisedView(), + }) } // BuildSegment builds a TCP segment based on the given Headers and payload. func (c *Context) BuildSegment(payload []byte, h *Headers) buffer.VectorisedView { + return c.BuildSegmentWithAddrs(payload, h, TestAddr, StackAddr) +} + +// BuildSegmentWithAddrs builds a TCP segment based on the given Headers, +// payload and source and destination IPv4 addresses. +func (c *Context) BuildSegmentWithAddrs(payload []byte, h *Headers, src, dst tcpip.Address) buffer.VectorisedView { // Allocate a buffer for data and headers. buf := buffer.NewView(header.TCPMinimumSize + header.IPv4MinimumSize + len(h.TCPOpts) + len(payload)) copy(buf[len(buf)-len(payload):], payload) @@ -319,8 +329,8 @@ func (c *Context) BuildSegment(payload []byte, h *Headers) buffer.VectorisedView TotalLength: uint16(len(buf)), TTL: 65, Protocol: uint8(tcp.ProtocolNumber), - SrcAddr: TestAddr, - DstAddr: StackAddr, + SrcAddr: src, + DstAddr: dst, }) ip.SetChecksum(^ip.CalculateChecksum()) @@ -337,7 +347,7 @@ func (c *Context) BuildSegment(payload []byte, h *Headers) buffer.VectorisedView }) // Calculate the TCP pseudo-header checksum. - xsum := header.PseudoHeaderChecksum(tcp.ProtocolNumber, TestAddr, StackAddr, uint16(len(t))) + xsum := header.PseudoHeaderChecksum(tcp.ProtocolNumber, src, dst, uint16(len(t))) // Calculate the TCP checksum and set it. xsum = header.Checksum(payload, xsum) @@ -350,13 +360,26 @@ func (c *Context) BuildSegment(payload []byte, h *Headers) buffer.VectorisedView // SendSegment sends a TCP segment that has already been built and written to a // buffer.VectorisedView. func (c *Context) SendSegment(s buffer.VectorisedView) { - c.linkEP.Inject(ipv4.ProtocolNumber, s) + c.linkEP.InjectInbound(ipv4.ProtocolNumber, tcpip.PacketBuffer{ + Data: s, + }) } // SendPacket builds and sends a TCP segment(with the provided payload & TCP // headers) in an IPv4 packet via the link layer endpoint. func (c *Context) SendPacket(payload []byte, h *Headers) { - c.linkEP.Inject(ipv4.ProtocolNumber, c.BuildSegment(payload, h)) + c.linkEP.InjectInbound(ipv4.ProtocolNumber, tcpip.PacketBuffer{ + Data: c.BuildSegment(payload, h), + }) +} + +// SendPacketWithAddrs builds and sends a TCP segment(with the provided payload +// & TCPheaders) in an IPv4 packet via the link layer endpoint using the +// provided source and destination IPv4 addresses. +func (c *Context) SendPacketWithAddrs(payload []byte, h *Headers, src, dst tcpip.Address) { + c.linkEP.InjectInbound(ipv4.ProtocolNumber, tcpip.PacketBuffer{ + Data: c.BuildSegmentWithAddrs(payload, h, src, dst), + }) } // SendAck sends an ACK packet. @@ -462,14 +485,15 @@ func (c *Context) CreateV6Endpoint(v6only bool) { // GetV6Packet reads a single packet from the link layer endpoint of the context // and asserts that it is an IPv6 Packet with the expected src/dest addresses. func (c *Context) GetV6Packet() []byte { + c.t.Helper() select { case p := <-c.linkEP.C: if p.Proto != ipv6.ProtocolNumber { c.t.Fatalf("Bad network protocol: got %v, wanted %v", p.Proto, ipv6.ProtocolNumber) } - b := make([]byte, len(p.Header)+len(p.Payload)) - copy(b, p.Header) - copy(b[len(p.Header):], p.Payload) + b := make([]byte, p.Pkt.Header.UsedLength()+p.Pkt.Data.Size()) + copy(b, p.Pkt.Header.View()) + copy(b[p.Pkt.Header.UsedLength():], p.Pkt.Data.ToView()) checker.IPv6(c.t, b, checker.SrcAddr(StackV6Addr), checker.DstAddr(TestV6Addr)) return b @@ -484,6 +508,13 @@ func (c *Context) GetV6Packet() []byte { // SendV6Packet builds and sends an IPv6 Packet via the link layer endpoint of // the context. func (c *Context) SendV6Packet(payload []byte, h *Headers) { + c.SendV6PacketWithAddrs(payload, h, TestV6Addr, StackV6Addr) +} + +// SendV6PacketWithAddrs builds and sends an IPv6 Packet via the link layer +// endpoint of the context using the provided source and destination IPv6 +// addresses. +func (c *Context) SendV6PacketWithAddrs(payload []byte, h *Headers, src, dst tcpip.Address) { // Allocate a buffer for data and headers. buf := buffer.NewView(header.TCPMinimumSize + header.IPv6MinimumSize + len(payload)) copy(buf[len(buf)-len(payload):], payload) @@ -494,8 +525,8 @@ func (c *Context) SendV6Packet(payload []byte, h *Headers) { PayloadLength: uint16(header.TCPMinimumSize + len(payload)), NextHeader: uint8(tcp.ProtocolNumber), HopLimit: 65, - SrcAddr: TestV6Addr, - DstAddr: StackV6Addr, + SrcAddr: src, + DstAddr: dst, }) // Initialize the TCP header. @@ -511,14 +542,16 @@ func (c *Context) SendV6Packet(payload []byte, h *Headers) { }) // Calculate the TCP pseudo-header checksum. - xsum := header.PseudoHeaderChecksum(tcp.ProtocolNumber, TestV6Addr, StackV6Addr, uint16(len(t))) + xsum := header.PseudoHeaderChecksum(tcp.ProtocolNumber, src, dst, uint16(len(t))) // Calculate the TCP checksum and set it. xsum = header.Checksum(payload, xsum) t.SetChecksum(^t.CalculateChecksum(xsum)) // Inject packet. - c.linkEP.Inject(ipv6.ProtocolNumber, buf.ToVectorisedView()) + c.linkEP.InjectInbound(ipv6.ProtocolNumber, tcpip.PacketBuffer{ + Data: buf.ToVectorisedView(), + }) } // CreateConnected creates a connected TCP endpoint. @@ -1059,3 +1092,9 @@ func (c *Context) SetGSOEnabled(enable bool) { func (c *Context) MSSWithoutOptions() uint16 { return uint16(c.linkEP.MTU() - header.IPv4MinimumSize - header.TCPMinimumSize) } + +// MSSWithoutOptionsV6 returns the value for the MSS used by the stack when no +// options are in use for IPv6 packets. +func (c *Context) MSSWithoutOptionsV6() uint16 { + return uint16(c.linkEP.MTU() - header.IPv6MinimumSize - header.TCPMinimumSize) +} diff --git a/pkg/tcpip/transport/udp/BUILD b/pkg/tcpip/transport/udp/BUILD index c9460aa0d..97e4d5825 100644 --- a/pkg/tcpip/transport/udp/BUILD +++ b/pkg/tcpip/transport/udp/BUILD @@ -34,6 +34,7 @@ go_library( "//pkg/tcpip/buffer", "//pkg/tcpip/header", "//pkg/tcpip/iptables", + "//pkg/tcpip/ports", "//pkg/tcpip/stack", "//pkg/tcpip/transport/raw", "//pkg/waiter", @@ -59,11 +60,3 @@ go_test( "//pkg/waiter", ], ) - -filegroup( - name = "autogen", - srcs = [ - "udp_packet_list.go", - ], - visibility = ["//:sandbox"], -) diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go index 6e87245b7..1ac4705af 100644 --- a/pkg/tcpip/transport/udp/endpoint.go +++ b/pkg/tcpip/transport/udp/endpoint.go @@ -21,6 +21,7 @@ import ( "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/stack" "gvisor.dev/gvisor/pkg/waiter" ) @@ -31,9 +32,6 @@ type udpPacket struct { senderAddress tcpip.FullAddress data buffer.VectorisedView `state:".(buffer.VectorisedView)"` timestamp int64 - // views is used as buffer for data when its length is large - // enough to store a VectorisedView. - views [8]buffer.View `state:"nosave"` } // EndpointState represents the state of a UDP endpoint. @@ -80,6 +78,7 @@ type endpoint struct { // change throughout the lifetime of the endpoint. stack *stack.Stack `state:"manual"` waiterQueue *waiter.Queue + uniqueID uint64 // The following fields are used to manage the receive queue, and are // protected by rcvMu. @@ -106,6 +105,11 @@ type endpoint struct { bindToDevice tcpip.NICID broadcast bool + // Values used to reserve a port or register a transport endpoint. + // (which ever happens first). + boundBindToDevice tcpip.NICID + boundPortFlags ports.Flags + // sendTOS represents IPv4 TOS or IPv6 TrafficClass, // applied while sending packets. Defaults to 0 as on Linux. sendTOS uint8 @@ -140,7 +144,7 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQue stack: s, TransportEndpointInfo: stack.TransportEndpointInfo{ NetProto: netProto, - TransProto: header.TCPProtocolNumber, + TransProto: header.UDPProtocolNumber, }, waiterQueue: waiterQueue, // RFC 1075 section 5.4 recommends a TTL of 1 for membership @@ -160,9 +164,15 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQue rcvBufSizeMax: 32 * 1024, sndBufSize: 32 * 1024, state: StateInitial, + uniqueID: s.UniqueID(), } } +// UniqueID implements stack.TransportEndpoint.UniqueID. +func (e *endpoint) UniqueID() uint64 { + return e.uniqueID +} + // Close puts the endpoint in a closed state and frees all resources // associated with it. func (e *endpoint) Close() { @@ -171,8 +181,10 @@ func (e *endpoint) Close() { switch e.state { case StateBound, StateConnected: - e.stack.UnregisterTransportEndpoint(e.RegisterNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.bindToDevice) - e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.bindToDevice) + e.stack.UnregisterTransportEndpoint(e.RegisterNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.boundBindToDevice) + e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.boundPortFlags, e.boundBindToDevice) + e.boundBindToDevice = 0 + e.boundPortFlags = ports.Flags{} } for _, mem := range e.multicastMemberships { @@ -278,7 +290,7 @@ func (e *endpoint) prepareForWrite(to *tcpip.FullAddress) (retry bool, err *tcpi // connectRoute establishes a route to the specified interface or the // configured multicast interface if no interface is specified and the // specified address is a multicast address. -func (e *endpoint) connectRoute(nicid tcpip.NICID, addr tcpip.FullAddress, netProto tcpip.NetworkProtocolNumber) (stack.Route, tcpip.NICID, *tcpip.Error) { +func (e *endpoint) connectRoute(nicID tcpip.NICID, addr tcpip.FullAddress, netProto tcpip.NetworkProtocolNumber) (stack.Route, tcpip.NICID, *tcpip.Error) { localAddr := e.ID.LocalAddress if isBroadcastOrMulticast(localAddr) { // A packet can only originate from a unicast address (i.e., an interface). @@ -286,20 +298,20 @@ func (e *endpoint) connectRoute(nicid tcpip.NICID, addr tcpip.FullAddress, netPr } if header.IsV4MulticastAddress(addr.Addr) || header.IsV6MulticastAddress(addr.Addr) { - if nicid == 0 { - nicid = e.multicastNICID + if nicID == 0 { + nicID = e.multicastNICID } - if localAddr == "" && nicid == 0 { + if localAddr == "" && nicID == 0 { localAddr = e.multicastAddr } } // Find a route to the desired destination. - r, err := e.stack.FindRoute(nicid, localAddr, addr.Addr, netProto, e.multicastLoop) + r, err := e.stack.FindRoute(nicID, localAddr, addr.Addr, netProto, e.multicastLoop) if err != nil { return stack.Route{}, 0, err } - return r, nicid, nil + return r, nicID, nil } // Write writes data to the endpoint's peer. This method does not block @@ -378,13 +390,13 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, <-c } else { // Reject destination address if it goes through a different // NIC than the endpoint was bound to. - nicid := to.NIC + nicID := to.NIC if e.BindNICID != 0 { - if nicid != 0 && nicid != e.BindNICID { + if nicID != 0 && nicID != e.BindNICID { return 0, nil, tcpip.ErrNoRoute } - nicid = e.BindNICID + nicID = e.BindNICID } if to.Addr == header.IPv4Broadcast && !e.broadcast { @@ -396,7 +408,7 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, <-c return 0, nil, err } - r, _, err := e.connectRoute(nicid, *to, netProto) + r, _, err := e.connectRoute(nicID, *to, netProto) if err != nil { return 0, nil, err } @@ -618,9 +630,9 @@ func (e *endpoint) SetSockOpt(opt interface{}) *tcpip.Error { e.bindToDevice = 0 return nil } - for nicid, nic := range e.stack.NICInfo() { + for nicID, nic := range e.stack.NICInfo() { if nic.Name == string(v) { - e.bindToDevice = nicid + e.bindToDevice = nicID return nil } } @@ -728,6 +740,10 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error { *o = tcpip.MulticastLoopOption(v) return nil + case *tcpip.ReuseAddressOption: + *o = 0 + return nil + case *tcpip.ReusePortOption: e.mu.RLock() v := e.reusePort @@ -809,7 +825,11 @@ func sendUDP(r *stack.Route, data buffer.VectorisedView, localPort, remotePort u if useDefaultTTL { ttl = r.DefaultTTL() } - if err := r.WritePacket(nil /* gso */, hdr, data, stack.NetworkHeaderParams{Protocol: ProtocolNumber, TTL: ttl, TOS: tos}); err != nil { + if err := r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: ProtocolNumber, TTL: ttl, TOS: tos}, tcpip.PacketBuffer{ + Header: hdr, + Data: data, + TransportHeader: buffer.View(udp), + }); err != nil { r.Stats().UDP.PacketSendErrors.Increment() return err } @@ -859,7 +879,10 @@ func (e *endpoint) Disconnect() *tcpip.Error { if e.state != StateConnected { return nil } - id := stack.TransportEndpointID{} + var ( + id stack.TransportEndpointID + btd tcpip.NICID + ) // Exclude ephemerally bound endpoints. if e.BindNICID != 0 || e.ID.LocalAddress == "" { var err *tcpip.Error @@ -867,7 +890,7 @@ func (e *endpoint) Disconnect() *tcpip.Error { LocalPort: e.ID.LocalPort, LocalAddress: e.ID.LocalAddress, } - id, err = e.registerWithStack(e.RegisterNICID, e.effectiveNetProtos, id) + id, btd, err = e.registerWithStack(e.RegisterNICID, e.effectiveNetProtos, id) if err != nil { return err } @@ -875,13 +898,15 @@ func (e *endpoint) Disconnect() *tcpip.Error { } else { if e.ID.LocalPort != 0 { // Release the ephemeral port. - e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.bindToDevice) + e.stack.ReleasePort(e.effectiveNetProtos, ProtocolNumber, e.ID.LocalAddress, e.ID.LocalPort, e.boundPortFlags, e.boundBindToDevice) + e.boundPortFlags = ports.Flags{} } e.state = StateInitial } - e.stack.UnregisterTransportEndpoint(e.RegisterNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.bindToDevice) + e.stack.UnregisterTransportEndpoint(e.RegisterNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.boundBindToDevice) e.ID = id + e.boundBindToDevice = btd e.route.Release() e.route = stack.Route{} e.dstPort = 0 @@ -903,7 +928,7 @@ func (e *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { e.mu.Lock() defer e.mu.Unlock() - nicid := addr.NIC + nicID := addr.NIC var localPort uint16 switch e.state { case StateInitial: @@ -913,16 +938,16 @@ func (e *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { break } - if nicid != 0 && nicid != e.BindNICID { + if nicID != 0 && nicID != e.BindNICID { return tcpip.ErrInvalidEndpointState } - nicid = e.BindNICID + nicID = e.BindNICID default: return tcpip.ErrInvalidEndpointState } - r, nicid, err := e.connectRoute(nicid, addr, netProto) + r, nicID, err := e.connectRoute(nicID, addr, netProto) if err != nil { return err } @@ -950,20 +975,21 @@ func (e *endpoint) Connect(addr tcpip.FullAddress) *tcpip.Error { } } - id, err = e.registerWithStack(nicid, netProtos, id) + id, btd, err := e.registerWithStack(nicID, netProtos, id) if err != nil { return err } // Remove the old registration. if e.ID.LocalPort != 0 { - e.stack.UnregisterTransportEndpoint(e.RegisterNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.bindToDevice) + e.stack.UnregisterTransportEndpoint(e.RegisterNICID, e.effectiveNetProtos, ProtocolNumber, e.ID, e, e.boundBindToDevice) } e.ID = id + e.boundBindToDevice = btd e.route = r.Clone() e.dstPort = addr.Port - e.RegisterNICID = nicid + e.RegisterNICID = nicID e.effectiveNetProtos = netProtos e.state = StateConnected @@ -1018,20 +1044,27 @@ func (*endpoint) Accept() (tcpip.Endpoint, *waiter.Queue, *tcpip.Error) { return nil, nil, tcpip.ErrNotSupported } -func (e *endpoint) registerWithStack(nicid tcpip.NICID, netProtos []tcpip.NetworkProtocolNumber, id stack.TransportEndpointID) (stack.TransportEndpointID, *tcpip.Error) { +func (e *endpoint) registerWithStack(nicID tcpip.NICID, netProtos []tcpip.NetworkProtocolNumber, id stack.TransportEndpointID) (stack.TransportEndpointID, tcpip.NICID, *tcpip.Error) { if e.ID.LocalPort == 0 { - port, err := e.stack.ReservePort(netProtos, ProtocolNumber, id.LocalAddress, id.LocalPort, e.reusePort, e.bindToDevice) + flags := ports.Flags{ + LoadBalanced: e.reusePort, + // FIXME(b/129164367): Support SO_REUSEADDR. + MostRecent: false, + } + port, err := e.stack.ReservePort(netProtos, ProtocolNumber, id.LocalAddress, id.LocalPort, flags, e.bindToDevice) if err != nil { - return id, err + return id, e.bindToDevice, err } + e.boundPortFlags = flags id.LocalPort = port } - err := e.stack.RegisterTransportEndpoint(nicid, netProtos, ProtocolNumber, id, e, e.reusePort, e.bindToDevice) + err := e.stack.RegisterTransportEndpoint(nicID, netProtos, ProtocolNumber, id, e, e.reusePort, e.bindToDevice) if err != nil { - e.stack.ReleasePort(netProtos, ProtocolNumber, id.LocalAddress, id.LocalPort, e.bindToDevice) + e.stack.ReleasePort(netProtos, ProtocolNumber, id.LocalAddress, id.LocalPort, e.boundPortFlags, e.bindToDevice) + e.boundPortFlags = ports.Flags{} } - return id, err + return id, e.bindToDevice, err } func (e *endpoint) bindLocked(addr tcpip.FullAddress) *tcpip.Error { @@ -1057,11 +1090,11 @@ func (e *endpoint) bindLocked(addr tcpip.FullAddress) *tcpip.Error { } } - nicid := addr.NIC + nicID := addr.NIC if len(addr.Addr) != 0 && !isBroadcastOrMulticast(addr.Addr) { // A local unicast address was specified, verify that it's valid. - nicid = e.stack.CheckLocalAddress(addr.NIC, netProto, addr.Addr) - if nicid == 0 { + nicID = e.stack.CheckLocalAddress(addr.NIC, netProto, addr.Addr) + if nicID == 0 { return tcpip.ErrBadLocalAddress } } @@ -1070,13 +1103,14 @@ func (e *endpoint) bindLocked(addr tcpip.FullAddress) *tcpip.Error { LocalPort: addr.Port, LocalAddress: addr.Addr, } - id, err = e.registerWithStack(nicid, netProtos, id) + id, btd, err := e.registerWithStack(nicID, netProtos, id) if err != nil { return err } e.ID = id - e.RegisterNICID = nicid + e.boundBindToDevice = btd + e.RegisterNICID = nicID e.effectiveNetProtos = netProtos // Mark endpoint as bound. @@ -1111,9 +1145,14 @@ func (e *endpoint) GetLocalAddress() (tcpip.FullAddress, *tcpip.Error) { e.mu.RLock() defer e.mu.RUnlock() + addr := e.ID.LocalAddress + if e.state == StateConnected { + addr = e.route.LocalAddress + } + return tcpip.FullAddress{ NIC: e.RegisterNICID, - Addr: e.ID.LocalAddress, + Addr: addr, Port: e.ID.LocalPort, }, nil } @@ -1154,17 +1193,17 @@ func (e *endpoint) Readiness(mask waiter.EventMask) waiter.EventMask { // HandlePacket is called by the stack when new packets arrive to this transport // endpoint. -func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv buffer.VectorisedView) { +func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) { // Get the header then trim it from the view. - hdr := header.UDP(vv.First()) - if int(hdr.Length()) > vv.Size() { + hdr := header.UDP(pkt.Data.First()) + if int(hdr.Length()) > pkt.Data.Size() { // Malformed packet. e.stack.Stats().UDP.MalformedPacketsReceived.Increment() e.stats.ReceiveErrors.MalformedPacketsReceived.Increment() return } - vv.TrimFront(header.UDPMinimumSize) + pkt.Data.TrimFront(header.UDPMinimumSize) e.rcvMu.Lock() e.stack.Stats().UDP.PacketsReceived.Increment() @@ -1188,18 +1227,18 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv wasEmpty := e.rcvBufSize == 0 // Push new packet into receive list and increment the buffer size. - pkt := &udpPacket{ + packet := &udpPacket{ senderAddress: tcpip.FullAddress{ NIC: r.NICID(), Addr: id.RemoteAddress, Port: hdr.SourcePort(), }, } - pkt.data = vv.Clone(pkt.views[:]) - e.rcvList.PushBack(pkt) - e.rcvBufSize += vv.Size() + packet.data = pkt.Data + e.rcvList.PushBack(packet) + e.rcvBufSize += pkt.Data.Size() - pkt.timestamp = e.stack.NowNanoseconds() + packet.timestamp = e.stack.NowNanoseconds() e.rcvMu.Unlock() @@ -1210,7 +1249,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, vv } // HandleControlPacket implements stack.TransportEndpoint.HandleControlPacket. -func (e *endpoint) HandleControlPacket(id stack.TransportEndpointID, typ stack.ControlType, extra uint32, vv buffer.VectorisedView) { +func (e *endpoint) HandleControlPacket(id stack.TransportEndpointID, typ stack.ControlType, extra uint32, pkt tcpip.PacketBuffer) { } // State implements tcpip.Endpoint.State. @@ -1234,6 +1273,9 @@ func (e *endpoint) Stats() tcpip.EndpointStats { return &e.stats } +// Wait implements tcpip.Endpoint.Wait. +func (*endpoint) Wait() {} + func isBroadcastOrMulticast(a tcpip.Address) bool { return a == header.IPv4Broadcast || header.IsV4MulticastAddress(a) || header.IsV6MulticastAddress(a) } diff --git a/pkg/tcpip/transport/udp/endpoint_state.go b/pkg/tcpip/transport/udp/endpoint_state.go index b227e353b..43fb047ed 100644 --- a/pkg/tcpip/transport/udp/endpoint_state.go +++ b/pkg/tcpip/transport/udp/endpoint_state.go @@ -109,7 +109,7 @@ func (e *endpoint) Resume(s *stack.Stack) { // pass it to the reservation machinery. id := e.ID e.ID.LocalPort = 0 - e.ID, err = e.registerWithStack(e.RegisterNICID, e.effectiveNetProtos, id) + e.ID, e.boundBindToDevice, err = e.registerWithStack(e.RegisterNICID, e.effectiveNetProtos, id) if err != nil { panic(err) } diff --git a/pkg/tcpip/transport/udp/forwarder.go b/pkg/tcpip/transport/udp/forwarder.go index d399ec722..fc706ede2 100644 --- a/pkg/tcpip/transport/udp/forwarder.go +++ b/pkg/tcpip/transport/udp/forwarder.go @@ -16,7 +16,6 @@ package udp import ( "gvisor.dev/gvisor/pkg/tcpip" - "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/stack" "gvisor.dev/gvisor/pkg/waiter" ) @@ -44,12 +43,12 @@ func NewForwarder(s *stack.Stack, handler func(*ForwarderRequest)) *Forwarder { // // This function is expected to be passed as an argument to the // stack.SetTransportProtocolHandler function. -func (f *Forwarder) HandlePacket(r *stack.Route, id stack.TransportEndpointID, netHeader buffer.View, vv buffer.VectorisedView) bool { +func (f *Forwarder) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) bool { f.handler(&ForwarderRequest{ stack: f.stack, route: r, id: id, - vv: vv, + pkt: pkt, }) return true @@ -62,7 +61,7 @@ type ForwarderRequest struct { stack *stack.Stack route *stack.Route id stack.TransportEndpointID - vv buffer.VectorisedView + pkt tcpip.PacketBuffer } // ID returns the 4-tuple (src address, src port, dst address, dst port) that @@ -90,7 +89,7 @@ func (r *ForwarderRequest) CreateEndpoint(queue *waiter.Queue) (tcpip.Endpoint, ep.rcvReady = true ep.rcvMu.Unlock() - ep.HandlePacket(r.route, r.id, r.vv) + ep.HandlePacket(r.route, r.id, r.pkt) return ep, nil } diff --git a/pkg/tcpip/transport/udp/protocol.go b/pkg/tcpip/transport/udp/protocol.go index de026880f..259c3072a 100644 --- a/pkg/tcpip/transport/udp/protocol.go +++ b/pkg/tcpip/transport/udp/protocol.go @@ -66,10 +66,10 @@ func (*protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) { // HandleUnknownDestinationPacket handles packets targeted at this protocol but // that don't match any existing endpoint. -func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, netHeader buffer.View, vv buffer.VectorisedView) bool { +func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, pkt tcpip.PacketBuffer) bool { // Get the header then trim it from the view. - hdr := header.UDP(vv.First()) - if int(hdr.Length()) > vv.Size() { + hdr := header.UDP(pkt.Data.First()) + if int(hdr.Length()) > pkt.Data.Size() { // Malformed packet. r.Stack().Stats().UDP.MalformedPacketsReceived.Increment() return true @@ -116,13 +116,18 @@ func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.Trans } headerLen := int(r.MaxHeaderLength()) + header.ICMPv4MinimumSize available := int(mtu) - headerLen - payloadLen := len(netHeader) + vv.Size() + payloadLen := len(pkt.NetworkHeader) + pkt.Data.Size() if payloadLen > available { payloadLen = available } - payload := buffer.NewVectorisedView(len(netHeader), []buffer.View{netHeader}) - payload.Append(vv) + // The buffers used by pkt may be used elsewhere in the system. + // For example, a raw or packet socket may use what UDP + // considers an unreachable destination. Thus we deep copy pkt + // to prevent multiple ownership and SR errors. + newNetHeader := append(buffer.View(nil), pkt.NetworkHeader...) + payload := newNetHeader.ToVectorisedView() + payload.Append(pkt.Data.ToView().ToVectorisedView()) payload.CapLength(payloadLen) hdr := buffer.NewPrependable(headerLen) @@ -130,7 +135,10 @@ func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.Trans pkt.SetType(header.ICMPv4DstUnreachable) pkt.SetCode(header.ICMPv4PortUnreachable) pkt.SetChecksum(header.ICMPv4Checksum(pkt, payload)) - r.WritePacket(nil /* gso */, hdr, payload, stack.NetworkHeaderParams{Protocol: header.ICMPv4ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}) + r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv4ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}, tcpip.PacketBuffer{ + Header: hdr, + Data: payload, + }) case header.IPv6AddressSize: if !r.Stack().AllowICMPMessage() { @@ -151,12 +159,12 @@ func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.Trans } headerLen := int(r.MaxHeaderLength()) + header.ICMPv6DstUnreachableMinimumSize available := int(mtu) - headerLen - payloadLen := len(netHeader) + vv.Size() + payloadLen := len(pkt.NetworkHeader) + pkt.Data.Size() if payloadLen > available { payloadLen = available } - payload := buffer.NewVectorisedView(len(netHeader), []buffer.View{netHeader}) - payload.Append(vv) + payload := buffer.NewVectorisedView(len(pkt.NetworkHeader), []buffer.View{pkt.NetworkHeader}) + payload.Append(pkt.Data) payload.CapLength(payloadLen) hdr := buffer.NewPrependable(headerLen) @@ -164,7 +172,10 @@ func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.Trans pkt.SetType(header.ICMPv6DstUnreachable) pkt.SetCode(header.ICMPv6PortUnreachable) pkt.SetChecksum(header.ICMPv6Checksum(pkt, r.LocalAddress, r.RemoteAddress, payload)) - r.WritePacket(nil /* gso */, hdr, payload, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}) + r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}, tcpip.PacketBuffer{ + Header: hdr, + Data: payload, + }) } return true } diff --git a/pkg/tcpip/transport/udp/udp_test.go b/pkg/tcpip/transport/udp/udp_test.go index b724d788c..7051a7a9c 100644 --- a/pkg/tcpip/transport/udp/udp_test.go +++ b/pkg/tcpip/transport/udp/udp_test.go @@ -356,9 +356,9 @@ func (c *testContext) getPacketAndVerify(flow testFlow, checkers ...checker.Netw if p.Proto != flow.netProto() { c.t.Fatalf("Bad network protocol: got %v, wanted %v", p.Proto, flow.netProto()) } - b := make([]byte, len(p.Header)+len(p.Payload)) - copy(b, p.Header) - copy(b[len(p.Header):], p.Payload) + + hdr := p.Pkt.Header.View() + b := append(hdr[:len(hdr):len(hdr)], p.Pkt.Data.ToView()...) h := flow.header4Tuple(outgoing) checkers := append( @@ -397,7 +397,8 @@ func (c *testContext) injectPacket(flow testFlow, payload []byte) { func (c *testContext) injectV6Packet(payload []byte, h *header4Tuple, valid bool) { // Allocate a buffer for data and headers. buf := buffer.NewView(header.UDPMinimumSize + header.IPv6MinimumSize + len(payload)) - copy(buf[len(buf)-len(payload):], payload) + payloadStart := len(buf) - len(payload) + copy(buf[payloadStart:], payload) // Initialize the IP header. ip := header.IPv6(buf) @@ -431,7 +432,11 @@ func (c *testContext) injectV6Packet(payload []byte, h *header4Tuple, valid bool u.SetChecksum(^u.CalculateChecksum(xsum)) // Inject packet. - c.linkEP.Inject(ipv6.ProtocolNumber, buf.ToVectorisedView()) + c.linkEP.InjectInbound(ipv6.ProtocolNumber, tcpip.PacketBuffer{ + Data: buf.ToVectorisedView(), + NetworkHeader: buffer.View(ip), + TransportHeader: buffer.View(u), + }) } // injectV4Packet creates a V4 test packet with the given payload and header @@ -441,7 +446,8 @@ func (c *testContext) injectV6Packet(payload []byte, h *header4Tuple, valid bool func (c *testContext) injectV4Packet(payload []byte, h *header4Tuple, valid bool) { // Allocate a buffer for data and headers. buf := buffer.NewView(header.UDPMinimumSize + header.IPv4MinimumSize + len(payload)) - copy(buf[len(buf)-len(payload):], payload) + payloadStart := len(buf) - len(payload) + copy(buf[payloadStart:], payload) // Initialize the IP header. ip := header.IPv4(buf) @@ -471,7 +477,12 @@ func (c *testContext) injectV4Packet(payload []byte, h *header4Tuple, valid bool u.SetChecksum(^u.CalculateChecksum(xsum)) // Inject packet. - c.linkEP.Inject(ipv4.ProtocolNumber, buf.ToVectorisedView()) + + c.linkEP.InjectInbound(ipv4.ProtocolNumber, tcpip.PacketBuffer{ + Data: buf.ToVectorisedView(), + NetworkHeader: buffer.View(ip), + TransportHeader: buffer.View(u), + }) } func newPayload() []byte { @@ -1442,8 +1453,8 @@ func TestV4UnknownDestination(t *testing.T) { select { case p := <-c.linkEP.C: var pkt []byte - pkt = append(pkt, p.Header...) - pkt = append(pkt, p.Payload...) + pkt = append(pkt, p.Pkt.Header.View()...) + pkt = append(pkt, p.Pkt.Data.ToView()...) if got, want := len(pkt), header.IPv4MinimumProcessableDatagramSize; got > want { t.Fatalf("got an ICMP packet of size: %d, want: sz <= %d", got, want) } @@ -1516,8 +1527,8 @@ func TestV6UnknownDestination(t *testing.T) { select { case p := <-c.linkEP.C: var pkt []byte - pkt = append(pkt, p.Header...) - pkt = append(pkt, p.Payload...) + pkt = append(pkt, p.Pkt.Header.View()...) + pkt = append(pkt, p.Pkt.Data.ToView()...) if got, want := len(pkt), header.IPv6MinimumMTU; got > want { t.Fatalf("got an ICMP packet of size: %d, want: sz <= %d", got, want) } |