diff options
Diffstat (limited to 'test/packetimpact/testbench')
| -rw-r--r-- | test/packetimpact/testbench/BUILD | 11 | ||||
| -rw-r--r-- | test/packetimpact/testbench/connections.go | 287 | ||||
| -rw-r--r-- | test/packetimpact/testbench/dut.go | 362 | ||||
| -rw-r--r-- | test/packetimpact/testbench/layers.go | 284 | ||||
| -rw-r--r-- | test/packetimpact/testbench/layers_test.go | 144 | ||||
| -rw-r--r-- | test/packetimpact/testbench/rawsockets.go | 6 |
6 files changed, 863 insertions, 231 deletions
diff --git a/test/packetimpact/testbench/BUILD b/test/packetimpact/testbench/BUILD index a34c81fcc..838a10ffe 100644 --- a/test/packetimpact/testbench/BUILD +++ b/test/packetimpact/testbench/BUILD @@ -1,4 +1,4 @@ -load("//tools:defs.bzl", "go_library") +load("//tools:defs.bzl", "go_library", "go_test") package( default_visibility = ["//test/packetimpact:__subpackages__"], @@ -16,6 +16,7 @@ go_library( ], deps = [ "//pkg/tcpip", + "//pkg/tcpip/buffer", "//pkg/tcpip/header", "//pkg/tcpip/seqnum", "//pkg/usermem", @@ -29,3 +30,11 @@ go_library( "@org_golang_x_sys//unix:go_default_library", ], ) + +go_test( + name = "testbench_test", + size = "small", + srcs = ["layers_test.go"], + library = ":testbench", + deps = ["//pkg/tcpip"], +) diff --git a/test/packetimpact/testbench/connections.go b/test/packetimpact/testbench/connections.go index b7aa63934..79c0ccf5c 100644 --- a/test/packetimpact/testbench/connections.go +++ b/test/packetimpact/testbench/connections.go @@ -21,6 +21,7 @@ import ( "fmt" "math/rand" "net" + "strings" "testing" "time" @@ -36,19 +37,6 @@ var remoteIPv4 = flag.String("remote_ipv4", "", "remote IPv4 address for test pa var localMAC = flag.String("local_mac", "", "local mac address for test packets") var remoteMAC = flag.String("remote_mac", "", "remote mac address for test packets") -// TCPIPv4 maintains state about a TCP/IPv4 connection. -type TCPIPv4 struct { - outgoing Layers - incoming Layers - LocalSeqNum seqnum.Value - RemoteSeqNum seqnum.Value - SynAck *TCP - sniffer Sniffer - injector Injector - portPickerFD int - t *testing.T -} - // pickPort makes a new socket and returns the socket FD and port. The caller // must close the FD when done with the port if there is no error. func pickPort() (int, uint16, error) { @@ -75,12 +63,25 @@ func pickPort() (int, uint16, error) { return fd, uint16(newSockAddrInet4.Port), nil } +// TCPIPv4 maintains state about a TCP/IPv4 connection. +type TCPIPv4 struct { + outgoing Layers + incoming Layers + LocalSeqNum seqnum.Value + RemoteSeqNum seqnum.Value + SynAck *TCP + sniffer Sniffer + injector Injector + portPickerFD int + t *testing.T +} + // tcpLayerIndex is the position of the TCP layer in the TCPIPv4 connection. It // is the third, after Ethernet and IPv4. const tcpLayerIndex int = 2 // NewTCPIPv4 creates a new TCPIPv4 connection with reasonable defaults. -func NewTCPIPv4(t *testing.T, dut DUT, outgoingTCP, incomingTCP TCP) TCPIPv4 { +func NewTCPIPv4(t *testing.T, outgoingTCP, incomingTCP TCP) TCPIPv4 { lMAC, err := tcpip.ParseMACAddress(*localMAC) if err != nil { t.Fatalf("can't parse localMAC %q: %s", *localMAC, err) @@ -109,18 +110,16 @@ func NewTCPIPv4(t *testing.T, dut DUT, outgoingTCP, incomingTCP TCP) TCPIPv4 { } newOutgoingTCP := &TCP{ - DataOffset: Uint8(header.TCPMinimumSize), - WindowSize: Uint16(32768), - SrcPort: &localPort, + SrcPort: &localPort, } if err := newOutgoingTCP.merge(outgoingTCP); err != nil { - t.Fatalf("can't merge %v into %v: %s", outgoingTCP, newOutgoingTCP, err) + t.Fatalf("can't merge %+v into %+v: %s", outgoingTCP, newOutgoingTCP, err) } newIncomingTCP := &TCP{ DstPort: &localPort, } if err := newIncomingTCP.merge(incomingTCP); err != nil { - t.Fatalf("can't merge %v into %v: %s", incomingTCP, newIncomingTCP, err) + t.Fatalf("can't merge %+v into %+v: %s", incomingTCP, newIncomingTCP, err) } return TCPIPv4{ outgoing: Layers{ @@ -149,8 +148,9 @@ func (conn *TCPIPv4) Close() { conn.portPickerFD = -1 } -// Send a packet with reasonable defaults and override some fields by tcp. -func (conn *TCPIPv4) Send(tcp TCP, additionalLayers ...Layer) { +// CreateFrame builds a frame for the connection with tcp overriding defaults +// and additionalLayers added after the TCP header. +func (conn *TCPIPv4) CreateFrame(tcp TCP, additionalLayers ...Layer) Layers { if tcp.SeqNum == nil { tcp.SeqNum = Uint32(uint32(conn.LocalSeqNum)) } @@ -159,30 +159,51 @@ func (conn *TCPIPv4) Send(tcp TCP, additionalLayers ...Layer) { } layersToSend := deepcopy.Copy(conn.outgoing).(Layers) if err := layersToSend[tcpLayerIndex].(*TCP).merge(tcp); err != nil { - conn.t.Fatalf("can't merge %v into %v: %s", tcp, layersToSend[tcpLayerIndex], err) + conn.t.Fatalf("can't merge %+v into %+v: %s", tcp, layersToSend[tcpLayerIndex], err) } layersToSend = append(layersToSend, additionalLayers...) - outBytes, err := layersToSend.toBytes() + return layersToSend +} + +// SendFrame sends a frame with reasonable defaults. +func (conn *TCPIPv4) SendFrame(frame Layers) { + outBytes, err := frame.toBytes() if err != nil { conn.t.Fatalf("can't build outgoing TCP packet: %s", err) } conn.injector.Send(outBytes) // Compute the next TCP sequence number. - for i := tcpLayerIndex + 1; i < len(layersToSend); i++ { - conn.LocalSeqNum.UpdateForward(seqnum.Size(layersToSend[i].length())) + for i := tcpLayerIndex + 1; i < len(frame); i++ { + conn.LocalSeqNum.UpdateForward(seqnum.Size(frame[i].length())) } + tcp := frame[tcpLayerIndex].(*TCP) if tcp.Flags != nil && *tcp.Flags&(header.TCPFlagSyn|header.TCPFlagFin) != 0 { conn.LocalSeqNum.UpdateForward(1) } } -// Recv gets a packet from the sniffer within the timeout provided. If no packet -// arrives before the timeout, it returns nil. +// Send a packet with reasonable defaults and override some fields by tcp. +func (conn *TCPIPv4) Send(tcp TCP, additionalLayers ...Layer) { + conn.SendFrame(conn.CreateFrame(tcp, additionalLayers...)) +} + +// Recv gets a packet from the sniffer within the timeout provided. +// If no packet arrives before the timeout, it returns nil. func (conn *TCPIPv4) Recv(timeout time.Duration) *TCP { + layers := conn.RecvFrame(timeout) + if tcpLayerIndex < len(layers) { + return layers[tcpLayerIndex].(*TCP) + } + return nil +} + +// RecvFrame gets a frame (of type Layers) within the timeout provided. +// If no frame arrives before the timeout, it returns nil. +func (conn *TCPIPv4) RecvFrame(timeout time.Duration) Layers { deadline := time.Now().Add(timeout) for { - timeout = deadline.Sub(time.Now()) + timeout = time.Until(deadline) if timeout <= 0 { break } @@ -190,10 +211,7 @@ func (conn *TCPIPv4) Recv(timeout time.Duration) *TCP { if b == nil { break } - layers, err := ParseEther(b) - if err != nil { - continue // Ignore packets that can't be parsed. - } + layers := Parse(ParseEther, b) if !conn.incoming.match(layers) { continue // Ignore packets that don't match the expected incoming. } @@ -205,41 +223,222 @@ func (conn *TCPIPv4) Recv(timeout time.Duration) *TCP { for i := tcpLayerIndex + 1; i < len(layers); i++ { conn.RemoteSeqNum.UpdateForward(seqnum.Size(layers[i].length())) } - return tcpHeader + return layers } return nil } // Expect a packet that matches the provided tcp within the timeout specified. -// If it doesn't arrive in time, the test fails. -func (conn *TCPIPv4) Expect(tcp TCP, timeout time.Duration) *TCP { +// If it doesn't arrive in time, it returns nil. +func (conn *TCPIPv4) Expect(tcp TCP, timeout time.Duration) (*TCP, error) { + // We cannot implement this directly using ExpectFrame as we cannot specify + // the Payload part. deadline := time.Now().Add(timeout) + var allTCP []string for { - timeout = deadline.Sub(time.Now()) - if timeout <= 0 { - return nil + var gotTCP *TCP + if timeout = time.Until(deadline); timeout > 0 { + gotTCP = conn.Recv(timeout) } - gotTCP := conn.Recv(timeout) if gotTCP == nil { - return nil + return nil, fmt.Errorf("got %d packets:\n%s", len(allTCP), strings.Join(allTCP, "\n")) } if tcp.match(gotTCP) { - return gotTCP + return gotTCP, nil + } + allTCP = append(allTCP, gotTCP.String()) + } +} + +// ExpectFrame expects a frame that matches the specified layers within the +// timeout specified. If it doesn't arrive in time, it returns nil. +func (conn *TCPIPv4) ExpectFrame(layers Layers, timeout time.Duration) Layers { + deadline := time.Now().Add(timeout) + for { + timeout = time.Until(deadline) + if timeout <= 0 { + return nil + } + gotLayers := conn.RecvFrame(timeout) + if layers.match(gotLayers) { + return gotLayers } } } +// ExpectData is a convenient method that expects a TCP packet along with +// the payload to arrive within the timeout specified. If it doesn't arrive +// in time, it causes a fatal test failure. +func (conn *TCPIPv4) ExpectData(tcp TCP, data []byte, timeout time.Duration) { + expected := []Layer{&Ether{}, &IPv4{}, &tcp} + if len(data) > 0 { + expected = append(expected, &Payload{Bytes: data}) + } + if conn.ExpectFrame(expected, timeout) == nil { + conn.t.Fatalf("expected to get a TCP frame %s with payload %x", &tcp, data) + } +} + // Handshake performs a TCP 3-way handshake. func (conn *TCPIPv4) Handshake() { // Send the SYN. conn.Send(TCP{Flags: Uint8(header.TCPFlagSyn)}) // Wait for the SYN-ACK. - conn.SynAck = conn.Expect(TCP{Flags: Uint8(header.TCPFlagSyn | header.TCPFlagAck)}, time.Second) - if conn.SynAck == nil { - conn.t.Fatalf("didn't get synack during handshake") + synAck, err := conn.Expect(TCP{Flags: Uint8(header.TCPFlagSyn | header.TCPFlagAck)}, time.Second) + if synAck == nil { + conn.t.Fatalf("didn't get synack during handshake: %s", err) } + conn.SynAck = synAck // Send an ACK. conn.Send(TCP{Flags: Uint8(header.TCPFlagAck)}) } + +// UDPIPv4 maintains state about a UDP/IPv4 connection. +type UDPIPv4 struct { + outgoing Layers + incoming Layers + sniffer Sniffer + injector Injector + portPickerFD int + t *testing.T +} + +// udpLayerIndex is the position of the UDP layer in the UDPIPv4 connection. It +// is the third, after Ethernet and IPv4. +const udpLayerIndex int = 2 + +// NewUDPIPv4 creates a new UDPIPv4 connection with reasonable defaults. +func NewUDPIPv4(t *testing.T, outgoingUDP, incomingUDP UDP) UDPIPv4 { + lMAC, err := tcpip.ParseMACAddress(*localMAC) + if err != nil { + t.Fatalf("can't parse localMAC %q: %s", *localMAC, err) + } + + rMAC, err := tcpip.ParseMACAddress(*remoteMAC) + if err != nil { + t.Fatalf("can't parse remoteMAC %q: %s", *remoteMAC, err) + } + + portPickerFD, localPort, err := pickPort() + if err != nil { + t.Fatalf("can't pick a port: %s", err) + } + lIP := tcpip.Address(net.ParseIP(*localIPv4).To4()) + rIP := tcpip.Address(net.ParseIP(*remoteIPv4).To4()) + + sniffer, err := NewSniffer(t) + if err != nil { + t.Fatalf("can't make new sniffer: %s", err) + } + + injector, err := NewInjector(t) + if err != nil { + t.Fatalf("can't make new injector: %s", err) + } + + newOutgoingUDP := &UDP{ + SrcPort: &localPort, + } + if err := newOutgoingUDP.merge(outgoingUDP); err != nil { + t.Fatalf("can't merge %+v into %+v: %s", outgoingUDP, newOutgoingUDP, err) + } + newIncomingUDP := &UDP{ + DstPort: &localPort, + } + if err := newIncomingUDP.merge(incomingUDP); err != nil { + t.Fatalf("can't merge %+v into %+v: %s", incomingUDP, newIncomingUDP, err) + } + return UDPIPv4{ + outgoing: Layers{ + &Ether{SrcAddr: &lMAC, DstAddr: &rMAC}, + &IPv4{SrcAddr: &lIP, DstAddr: &rIP}, + newOutgoingUDP}, + incoming: Layers{ + &Ether{SrcAddr: &rMAC, DstAddr: &lMAC}, + &IPv4{SrcAddr: &rIP, DstAddr: &lIP}, + newIncomingUDP}, + sniffer: sniffer, + injector: injector, + portPickerFD: portPickerFD, + t: t, + } +} + +// Close the injector and sniffer associated with this connection. +func (conn *UDPIPv4) Close() { + conn.sniffer.Close() + conn.injector.Close() + if err := unix.Close(conn.portPickerFD); err != nil { + conn.t.Fatalf("can't close portPickerFD: %s", err) + } + conn.portPickerFD = -1 +} + +// CreateFrame builds a frame for the connection with the provided udp +// overriding defaults and the additionalLayers added after the UDP header. +func (conn *UDPIPv4) CreateFrame(udp UDP, additionalLayers ...Layer) Layers { + layersToSend := deepcopy.Copy(conn.outgoing).(Layers) + if err := layersToSend[udpLayerIndex].(*UDP).merge(udp); err != nil { + conn.t.Fatalf("can't merge %+v into %+v: %s", udp, layersToSend[udpLayerIndex], err) + } + layersToSend = append(layersToSend, additionalLayers...) + return layersToSend +} + +// SendFrame sends a frame with reasonable defaults. +func (conn *UDPIPv4) SendFrame(frame Layers) { + outBytes, err := frame.toBytes() + if err != nil { + conn.t.Fatalf("can't build outgoing UDP packet: %s", err) + } + conn.injector.Send(outBytes) +} + +// Send a packet with reasonable defaults and override some fields by udp. +func (conn *UDPIPv4) Send(udp UDP, additionalLayers ...Layer) { + conn.SendFrame(conn.CreateFrame(udp, additionalLayers...)) +} + +// Recv gets a packet from the sniffer within the timeout provided. If no packet +// arrives before the timeout, it returns nil. +func (conn *UDPIPv4) Recv(timeout time.Duration) *UDP { + deadline := time.Now().Add(timeout) + for { + timeout = time.Until(deadline) + if timeout <= 0 { + break + } + b := conn.sniffer.Recv(timeout) + if b == nil { + break + } + layers := Parse(ParseEther, b) + if !conn.incoming.match(layers) { + continue // Ignore packets that don't match the expected incoming. + } + return (layers[udpLayerIndex]).(*UDP) + } + return nil +} + +// Expect a packet that matches the provided udp within the timeout specified. +// If it doesn't arrive in time, the test fails. +func (conn *UDPIPv4) Expect(udp UDP, timeout time.Duration) (*UDP, error) { + deadline := time.Now().Add(timeout) + var allUDP []string + for { + var gotUDP *UDP + if timeout = time.Until(deadline); timeout > 0 { + gotUDP = conn.Recv(timeout) + } + if gotUDP == nil { + return nil, fmt.Errorf("got %d packets:\n%s", len(allUDP), strings.Join(allUDP, "\n")) + } + if udp.match(gotUDP) { + return gotUDP, nil + } + allUDP = append(allUDP, gotUDP.String()) + } +} diff --git a/test/packetimpact/testbench/dut.go b/test/packetimpact/testbench/dut.go index 8ea1706d3..9335909c0 100644 --- a/test/packetimpact/testbench/dut.go +++ b/test/packetimpact/testbench/dut.go @@ -65,33 +65,6 @@ func (dut *DUT) TearDown() { dut.conn.Close() } -// SocketWithErrno calls socket on the DUT and returns the fd and errno. -func (dut *DUT) SocketWithErrno(domain, typ, proto int32) (int32, error) { - dut.t.Helper() - req := pb.SocketRequest{ - Domain: domain, - Type: typ, - Protocol: proto, - } - ctx := context.Background() - resp, err := dut.posixServer.Socket(ctx, &req) - if err != nil { - dut.t.Fatalf("failed to call Socket: %s", err) - } - return resp.GetFd(), syscall.Errno(resp.GetErrno_()) -} - -// Socket calls socket on the DUT and returns the file descriptor. If socket -// fails on the DUT, the test ends. -func (dut *DUT) Socket(domain, typ, proto int32) int32 { - dut.t.Helper() - fd, err := dut.SocketWithErrno(domain, typ, proto) - if fd < 0 { - dut.t.Fatalf("failed to create socket: %s", err) - } - return fd -} - func (dut *DUT) sockaddrToProto(sa unix.Sockaddr) *pb.Sockaddr { dut.t.Helper() switch s := sa.(type) { @@ -142,14 +115,95 @@ func (dut *DUT) protoToSockaddr(sa *pb.Sockaddr) unix.Sockaddr { return nil } +// CreateBoundSocket makes a new socket on the DUT, with type typ and protocol +// proto, and bound to the IP address addr. Returns the new file descriptor and +// the port that was selected on the DUT. +func (dut *DUT) CreateBoundSocket(typ, proto int32, addr net.IP) (int32, uint16) { + dut.t.Helper() + var fd int32 + if addr.To4() != nil { + fd = dut.Socket(unix.AF_INET, typ, proto) + sa := unix.SockaddrInet4{} + copy(sa.Addr[:], addr.To4()) + dut.Bind(fd, &sa) + } else if addr.To16() != nil { + fd = dut.Socket(unix.AF_INET6, typ, proto) + sa := unix.SockaddrInet6{} + copy(sa.Addr[:], addr.To16()) + dut.Bind(fd, &sa) + } else { + dut.t.Fatal("unknown ip addr type for remoteIP") + } + sa := dut.GetSockName(fd) + var port int + switch s := sa.(type) { + case *unix.SockaddrInet4: + port = s.Port + case *unix.SockaddrInet6: + port = s.Port + default: + dut.t.Fatalf("unknown sockaddr type from getsockname: %t", sa) + } + return fd, uint16(port) +} + +// CreateListener makes a new TCP connection. If it fails, the test ends. +func (dut *DUT) CreateListener(typ, proto, backlog int32) (int32, uint16) { + fd, remotePort := dut.CreateBoundSocket(typ, proto, net.ParseIP(*remoteIPv4)) + dut.Listen(fd, backlog) + return fd, remotePort +} + +// All the functions that make gRPC calls to the Posix service are below, sorted +// alphabetically. + +// Accept calls accept on the DUT and causes a fatal test failure if it doesn't +// succeed. If more control over the timeout or error handling is needed, use +// AcceptWithErrno. +func (dut *DUT) Accept(sockfd int32) (int32, unix.Sockaddr) { + dut.t.Helper() + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + fd, sa, err := dut.AcceptWithErrno(ctx, sockfd) + if fd < 0 { + dut.t.Fatalf("failed to accept: %s", err) + } + return fd, sa +} + +// AcceptWithErrno calls accept on the DUT. +func (dut *DUT) AcceptWithErrno(ctx context.Context, sockfd int32) (int32, unix.Sockaddr, error) { + dut.t.Helper() + req := pb.AcceptRequest{ + Sockfd: sockfd, + } + resp, err := dut.posixServer.Accept(ctx, &req) + if err != nil { + dut.t.Fatalf("failed to call Accept: %s", err) + } + return resp.GetFd(), dut.protoToSockaddr(resp.GetAddr()), syscall.Errno(resp.GetErrno_()) +} + +// Bind calls bind on the DUT and causes a fatal test failure if it doesn't +// succeed. If more control over the timeout or error handling is +// needed, use BindWithErrno. +func (dut *DUT) Bind(fd int32, sa unix.Sockaddr) { + dut.t.Helper() + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, err := dut.BindWithErrno(ctx, fd, sa) + if ret != 0 { + dut.t.Fatalf("failed to bind socket: %s", err) + } +} + // BindWithErrno calls bind on the DUT. -func (dut *DUT) BindWithErrno(fd int32, sa unix.Sockaddr) (int32, error) { +func (dut *DUT) BindWithErrno(ctx context.Context, fd int32, sa unix.Sockaddr) (int32, error) { dut.t.Helper() req := pb.BindRequest{ Sockfd: fd, Addr: dut.sockaddrToProto(sa), } - ctx := context.Background() resp, err := dut.posixServer.Bind(ctx, &req) if err != nil { dut.t.Fatalf("failed to call Bind: %s", err) @@ -157,23 +211,52 @@ func (dut *DUT) BindWithErrno(fd int32, sa unix.Sockaddr) (int32, error) { return resp.GetRet(), syscall.Errno(resp.GetErrno_()) } -// Bind calls bind on the DUT and causes a fatal test failure if it doesn't -// succeed. -func (dut *DUT) Bind(fd int32, sa unix.Sockaddr) { +// Close calls close on the DUT and causes a fatal test failure if it doesn't +// succeed. If more control over the timeout or error handling is needed, use +// CloseWithErrno. +func (dut *DUT) Close(fd int32) { dut.t.Helper() - ret, err := dut.BindWithErrno(fd, sa) + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, err := dut.CloseWithErrno(ctx, fd) if ret != 0 { - dut.t.Fatalf("failed to bind socket: %s", err) + dut.t.Fatalf("failed to close: %s", err) } } +// CloseWithErrno calls close on the DUT. +func (dut *DUT) CloseWithErrno(ctx context.Context, fd int32) (int32, error) { + dut.t.Helper() + req := pb.CloseRequest{ + Fd: fd, + } + resp, err := dut.posixServer.Close(ctx, &req) + if err != nil { + dut.t.Fatalf("failed to call Close: %s", err) + } + return resp.GetRet(), syscall.Errno(resp.GetErrno_()) +} + +// GetSockName calls getsockname on the DUT and causes a fatal test failure if +// it doesn't succeed. If more control over the timeout or error handling is +// needed, use GetSockNameWithErrno. +func (dut *DUT) GetSockName(sockfd int32) unix.Sockaddr { + dut.t.Helper() + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, sa, err := dut.GetSockNameWithErrno(ctx, sockfd) + if ret != 0 { + dut.t.Fatalf("failed to getsockname: %s", err) + } + return sa +} + // GetSockNameWithErrno calls getsockname on the DUT. -func (dut *DUT) GetSockNameWithErrno(sockfd int32) (int32, unix.Sockaddr, error) { +func (dut *DUT) GetSockNameWithErrno(ctx context.Context, sockfd int32) (int32, unix.Sockaddr, error) { dut.t.Helper() req := pb.GetSockNameRequest{ Sockfd: sockfd, } - ctx := context.Background() resp, err := dut.posixServer.GetSockName(ctx, &req) if err != nil { dut.t.Fatalf("failed to call Bind: %s", err) @@ -181,26 +264,26 @@ func (dut *DUT) GetSockNameWithErrno(sockfd int32) (int32, unix.Sockaddr, error) return resp.GetRet(), dut.protoToSockaddr(resp.GetAddr()), syscall.Errno(resp.GetErrno_()) } -// GetSockName calls getsockname on the DUT and causes a fatal test failure if -// it doens't succeed. -func (dut *DUT) GetSockName(sockfd int32) unix.Sockaddr { +// Listen calls listen on the DUT and causes a fatal test failure if it doesn't +// succeed. If more control over the timeout or error handling is needed, use +// ListenWithErrno. +func (dut *DUT) Listen(sockfd, backlog int32) { dut.t.Helper() - ret, sa, err := dut.GetSockNameWithErrno(sockfd) + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, err := dut.ListenWithErrno(ctx, sockfd, backlog) if ret != 0 { - dut.t.Fatalf("failed to getsockname: %s", err) + dut.t.Fatalf("failed to listen: %s", err) } - return sa } // ListenWithErrno calls listen on the DUT. -func (dut *DUT) ListenWithErrno(sockfd, backlog int32) (int32, error) { +func (dut *DUT) ListenWithErrno(ctx context.Context, sockfd, backlog int32) (int32, error) { dut.t.Helper() req := pb.ListenRequest{ Sockfd: sockfd, Backlog: backlog, } - ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) - defer cancel() resp, err := dut.posixServer.Listen(ctx, &req) if err != nil { dut.t.Fatalf("failed to call Listen: %s", err) @@ -208,44 +291,54 @@ func (dut *DUT) ListenWithErrno(sockfd, backlog int32) (int32, error) { return resp.GetRet(), syscall.Errno(resp.GetErrno_()) } -// Listen calls listen on the DUT and causes a fatal test failure if it doesn't -// succeed. -func (dut *DUT) Listen(sockfd, backlog int32) { +// Send calls send on the DUT and causes a fatal test failure if it doesn't +// succeed. If more control over the timeout or error handling is needed, use +// SendWithErrno. +func (dut *DUT) Send(sockfd int32, buf []byte, flags int32) int32 { dut.t.Helper() - ret, err := dut.ListenWithErrno(sockfd, backlog) - if ret != 0 { - dut.t.Fatalf("failed to listen: %s", err) + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, err := dut.SendWithErrno(ctx, sockfd, buf, flags) + if ret == -1 { + dut.t.Fatalf("failed to send: %s", err) } + return ret } -// AcceptWithErrno calls accept on the DUT. -func (dut *DUT) AcceptWithErrno(sockfd int32) (int32, unix.Sockaddr, error) { +// SendWithErrno calls send on the DUT. +func (dut *DUT) SendWithErrno(ctx context.Context, sockfd int32, buf []byte, flags int32) (int32, error) { dut.t.Helper() - req := pb.AcceptRequest{ + req := pb.SendRequest{ Sockfd: sockfd, + Buf: buf, + Flags: flags, } - ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) - defer cancel() - resp, err := dut.posixServer.Accept(ctx, &req) + resp, err := dut.posixServer.Send(ctx, &req) if err != nil { - dut.t.Fatalf("failed to call Accept: %s", err) + dut.t.Fatalf("failed to call Send: %s", err) } - return resp.GetFd(), dut.protoToSockaddr(resp.GetAddr()), syscall.Errno(resp.GetErrno_()) + return resp.GetRet(), syscall.Errno(resp.GetErrno_()) } -// Accept calls accept on the DUT and causes a fatal test failure if it doesn't -// succeed. -func (dut *DUT) Accept(sockfd int32) (int32, unix.Sockaddr) { +// SetSockOpt calls setsockopt on the DUT and causes a fatal test failure if it +// doesn't succeed. If more control over the timeout or error handling is +// needed, use SetSockOptWithErrno. Because endianess and the width of values +// might differ between the testbench and DUT architectures, prefer to use a +// more specific SetSockOptXxx function. +func (dut *DUT) SetSockOpt(sockfd, level, optname int32, optval []byte) { dut.t.Helper() - fd, sa, err := dut.AcceptWithErrno(sockfd) - if fd < 0 { - dut.t.Fatalf("failed to accept: %s", err) + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, err := dut.SetSockOptWithErrno(ctx, sockfd, level, optname, optval) + if ret != 0 { + dut.t.Fatalf("failed to SetSockOpt: %s", err) } - return fd, sa } -// SetSockOptWithErrno calls setsockopt on the DUT. -func (dut *DUT) SetSockOptWithErrno(sockfd, level, optname int32, optval []byte) (int32, error) { +// SetSockOptWithErrno calls setsockopt on the DUT. Because endianess and the +// width of values might differ between the testbench and DUT architectures, +// prefer to use a more specific SetSockOptXxxWithErrno function. +func (dut *DUT) SetSockOptWithErrno(ctx context.Context, sockfd, level, optname int32, optval []byte) (int32, error) { dut.t.Helper() req := pb.SetSockOptRequest{ Sockfd: sockfd, @@ -253,8 +346,6 @@ func (dut *DUT) SetSockOptWithErrno(sockfd, level, optname int32, optval []byte) Optname: optname, Optval: optval, } - ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) - defer cancel() resp, err := dut.posixServer.SetSockOpt(ctx, &req) if err != nil { dut.t.Fatalf("failed to call SetSockOpt: %s", err) @@ -262,19 +353,51 @@ func (dut *DUT) SetSockOptWithErrno(sockfd, level, optname int32, optval []byte) return resp.GetRet(), syscall.Errno(resp.GetErrno_()) } -// SetSockOpt calls setsockopt on the DUT and causes a fatal test failure if it -// doesn't succeed. -func (dut *DUT) SetSockOpt(sockfd, level, optname int32, optval []byte) { +// SetSockOptInt calls setsockopt on the DUT and causes a fatal test failure +// if it doesn't succeed. If more control over the int optval or error handling +// is needed, use SetSockOptIntWithErrno. +func (dut *DUT) SetSockOptInt(sockfd, level, optname, optval int32) { dut.t.Helper() - ret, err := dut.SetSockOptWithErrno(sockfd, level, optname, optval) + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, err := dut.SetSockOptIntWithErrno(ctx, sockfd, level, optname, optval) if ret != 0 { - dut.t.Fatalf("failed to SetSockOpt: %s", err) + dut.t.Fatalf("failed to SetSockOptInt: %s", err) + } +} + +// SetSockOptIntWithErrno calls setsockopt with an integer optval. +func (dut *DUT) SetSockOptIntWithErrno(ctx context.Context, sockfd, level, optname, optval int32) (int32, error) { + dut.t.Helper() + req := pb.SetSockOptIntRequest{ + Sockfd: sockfd, + Level: level, + Optname: optname, + Intval: optval, + } + resp, err := dut.posixServer.SetSockOptInt(ctx, &req) + if err != nil { + dut.t.Fatalf("failed to call SetSockOptInt: %s", err) + } + return resp.GetRet(), syscall.Errno(resp.GetErrno_()) +} + +// SetSockOptTimeval calls setsockopt on the DUT and causes a fatal test failure +// if it doesn't succeed. If more control over the timeout or error handling is +// needed, use SetSockOptTimevalWithErrno. +func (dut *DUT) SetSockOptTimeval(sockfd, level, optname int32, tv *unix.Timeval) { + dut.t.Helper() + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, err := dut.SetSockOptTimevalWithErrno(ctx, sockfd, level, optname, tv) + if ret != 0 { + dut.t.Fatalf("failed to SetSockOptTimeval: %s", err) } } // SetSockOptTimevalWithErrno calls setsockopt with the timeval converted to // bytes. -func (dut *DUT) SetSockOptTimevalWithErrno(sockfd, level, optname int32, tv *unix.Timeval) (int32, error) { +func (dut *DUT) SetSockOptTimevalWithErrno(ctx context.Context, sockfd, level, optname int32, tv *unix.Timeval) (int32, error) { dut.t.Helper() timeval := pb.Timeval{ Seconds: int64(tv.Sec), @@ -286,8 +409,6 @@ func (dut *DUT) SetSockOptTimevalWithErrno(sockfd, level, optname int32, tv *uni Optname: optname, Timeval: &timeval, } - ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) - defer cancel() resp, err := dut.posixServer.SetSockOptTimeval(ctx, &req) if err != nil { dut.t.Fatalf("failed to call SetSockOptTimeval: %s", err) @@ -295,69 +416,58 @@ func (dut *DUT) SetSockOptTimevalWithErrno(sockfd, level, optname int32, tv *uni return resp.GetRet(), syscall.Errno(resp.GetErrno_()) } -// SetSockOptTimeval calls setsockopt on the DUT and causes a fatal test failure -// if it doesn't succeed. -func (dut *DUT) SetSockOptTimeval(sockfd, level, optname int32, tv *unix.Timeval) { +// Socket calls socket on the DUT and returns the file descriptor. If socket +// fails on the DUT, the test ends. +func (dut *DUT) Socket(domain, typ, proto int32) int32 { dut.t.Helper() - ret, err := dut.SetSockOptTimevalWithErrno(sockfd, level, optname, tv) - if ret != 0 { - dut.t.Fatalf("failed to SetSockOptTimeval: %s", err) + fd, err := dut.SocketWithErrno(domain, typ, proto) + if fd < 0 { + dut.t.Fatalf("failed to create socket: %s", err) } + return fd } -// CloseWithErrno calls close on the DUT. -func (dut *DUT) CloseWithErrno(fd int32) (int32, error) { +// SocketWithErrno calls socket on the DUT and returns the fd and errno. +func (dut *DUT) SocketWithErrno(domain, typ, proto int32) (int32, error) { dut.t.Helper() - req := pb.CloseRequest{ - Fd: fd, + req := pb.SocketRequest{ + Domain: domain, + Type: typ, + Protocol: proto, } - ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) - defer cancel() - resp, err := dut.posixServer.Close(ctx, &req) + ctx := context.Background() + resp, err := dut.posixServer.Socket(ctx, &req) if err != nil { - dut.t.Fatalf("failed to call Close: %s", err) + dut.t.Fatalf("failed to call Socket: %s", err) } - return resp.GetRet(), syscall.Errno(resp.GetErrno_()) + return resp.GetFd(), syscall.Errno(resp.GetErrno_()) } -// Close calls close on the DUT and causes a fatal test failure if it doesn't -// succeed. -func (dut *DUT) Close(fd int32) { +// Recv calls recv on the DUT and causes a fatal test failure if it doesn't +// succeed. If more control over the timeout or error handling is needed, use +// RecvWithErrno. +func (dut *DUT) Recv(sockfd, len, flags int32) []byte { dut.t.Helper() - ret, err := dut.CloseWithErrno(fd) - if ret != 0 { - dut.t.Fatalf("failed to close: %s", err) + ctx, cancel := context.WithTimeout(context.Background(), *rpcTimeout) + defer cancel() + ret, buf, err := dut.RecvWithErrno(ctx, sockfd, len, flags) + if ret == -1 { + dut.t.Fatalf("failed to recv: %s", err) } + return buf } -// CreateListener makes a new TCP connection. If it fails, the test ends. -func (dut *DUT) CreateListener(typ, proto, backlog int32) (int32, uint16) { +// RecvWithErrno calls recv on the DUT. +func (dut *DUT) RecvWithErrno(ctx context.Context, sockfd, len, flags int32) (int32, []byte, error) { dut.t.Helper() - addr := net.ParseIP(*remoteIPv4) - var fd int32 - if addr.To4() != nil { - fd = dut.Socket(unix.AF_INET, typ, proto) - sa := unix.SockaddrInet4{} - copy(sa.Addr[:], addr.To4()) - dut.Bind(fd, &sa) - } else if addr.To16() != nil { - fd = dut.Socket(unix.AF_INET6, typ, proto) - sa := unix.SockaddrInet6{} - copy(sa.Addr[:], addr.To16()) - dut.Bind(fd, &sa) - } else { - dut.t.Fatal("unknown ip addr type for remoteIP") + req := pb.RecvRequest{ + Sockfd: sockfd, + Len: len, + Flags: flags, } - sa := dut.GetSockName(fd) - var port int - switch s := sa.(type) { - case *unix.SockaddrInet4: - port = s.Port - case *unix.SockaddrInet6: - port = s.Port - default: - dut.t.Fatalf("unknown sockaddr type from getsockname: %t", sa) + resp, err := dut.posixServer.Recv(ctx, &req) + if err != nil { + dut.t.Fatalf("failed to call Recv: %s", err) } - dut.Listen(fd, backlog) - return fd, uint16(port) + return resp.GetRet(), resp.GetBuf(), syscall.Errno(resp.GetErrno_()) } diff --git a/test/packetimpact/testbench/layers.go b/test/packetimpact/testbench/layers.go index 35fa4dcb6..b467c15cc 100644 --- a/test/packetimpact/testbench/layers.go +++ b/test/packetimpact/testbench/layers.go @@ -17,11 +17,13 @@ package testbench import ( "fmt" "reflect" + "strings" "github.com/google/go-cmp/cmp" "github.com/google/go-cmp/cmp/cmpopts" "github.com/imdario/mergo" "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" ) @@ -31,6 +33,8 @@ import ( // Layer contains all the fields of the encapsulation. Each field is a pointer // and may be nil. type Layer interface { + fmt.Stringer + // toBytes converts the Layer into bytes. In places where the Layer's field // isn't nil, the value that is pointed to is used. When the field is nil, a // reasonable default for the Layer is used. For example, "64" for IPv4 TTL @@ -42,7 +46,8 @@ type Layer interface { // match checks if the current Layer matches the provided Layer. If either // Layer has a nil in a given field, that field is considered matching. - // Otherwise, the values pointed to by the fields must match. + // Otherwise, the values pointed to by the fields must match. The LayerBase is + // ignored. match(Layer) bool // length in bytes of the current encapsulation @@ -83,21 +88,42 @@ func (lb *LayerBase) setPrev(l Layer) { lb.prevLayer = l } +// equalLayer compares that two Layer structs match while ignoring field in +// which either input has a nil and also ignoring the LayerBase of the inputs. func equalLayer(x, y Layer) bool { + // opt ignores comparison pairs where either of the inputs is a nil. opt := cmp.FilterValues(func(x, y interface{}) bool { - if reflect.ValueOf(x).Kind() == reflect.Ptr && reflect.ValueOf(x).IsNil() { - return true - } - if reflect.ValueOf(y).Kind() == reflect.Ptr && reflect.ValueOf(y).IsNil() { - return true + for _, l := range []interface{}{x, y} { + v := reflect.ValueOf(l) + if (v.Kind() == reflect.Ptr || v.Kind() == reflect.Slice) && v.IsNil() { + return true + } } return false - }, cmp.Ignore()) - return cmp.Equal(x, y, opt, cmpopts.IgnoreUnexported(LayerBase{})) + return cmp.Equal(x, y, opt, cmpopts.IgnoreTypes(LayerBase{})) +} + +func stringLayer(l Layer) string { + v := reflect.ValueOf(l).Elem() + t := v.Type() + var ret []string + for i := 0; i < v.NumField(); i++ { + t := t.Field(i) + if t.Anonymous { + // Ignore the LayerBase in the Layer struct. + continue + } + v := v.Field(i) + if v.IsNil() { + continue + } + ret = append(ret, fmt.Sprintf("%s:%v", t.Name, reflect.Indirect(v))) + } + return fmt.Sprintf("&%s{%s}", t, strings.Join(ret, " ")) } -// Ether can construct and match the ethernet encapsulation. +// Ether can construct and match an ethernet encapsulation. type Ether struct { LayerBase SrcAddr *tcpip.LinkAddress @@ -105,6 +131,10 @@ type Ether struct { Type *tcpip.NetworkProtocolNumber } +func (l *Ether) String() string { + return stringLayer(l) +} + func (l *Ether) toBytes() ([]byte, error) { b := make([]byte, header.EthernetMinimumSize) h := header.Ethernet(b) @@ -123,7 +153,7 @@ func (l *Ether) toBytes() ([]byte, error) { fields.Type = header.IPv4ProtocolNumber default: // TODO(b/150301488): Support more protocols, like IPv6. - return nil, fmt.Errorf("can't deduce the ethernet header's next protocol: %d", n) + return nil, fmt.Errorf("ethernet header's next layer is unrecognized: %#v", n) } } h.Encode(fields) @@ -142,27 +172,46 @@ func NetworkProtocolNumber(v tcpip.NetworkProtocolNumber) *tcpip.NetworkProtocol return &v } +// LayerParser parses the input bytes and returns a Layer along with the next +// LayerParser to run. If there is no more parsing to do, the returned +// LayerParser is nil. +type LayerParser func([]byte) (Layer, LayerParser) + +// Parse parses bytes starting with the first LayerParser and using successive +// LayerParsers until all the bytes are parsed. +func Parse(parser LayerParser, b []byte) Layers { + var layers Layers + for { + var layer Layer + layer, parser = parser(b) + layers = append(layers, layer) + if parser == nil { + break + } + b = b[layer.length():] + } + layers.linkLayers() + return layers +} + // ParseEther parses the bytes assuming that they start with an ethernet header // and continues parsing further encapsulations. -func ParseEther(b []byte) (Layers, error) { +func ParseEther(b []byte) (Layer, LayerParser) { h := header.Ethernet(b) ether := Ether{ SrcAddr: LinkAddress(h.SourceAddress()), DstAddr: LinkAddress(h.DestinationAddress()), Type: NetworkProtocolNumber(h.Type()), } - layers := Layers{ðer} + var nextParser LayerParser switch h.Type() { case header.IPv4ProtocolNumber: - moreLayers, err := ParseIPv4(b[ether.length():]) - if err != nil { - return nil, err - } - return append(layers, moreLayers...), nil + nextParser = ParseIPv4 default: - // TODO(b/150301488): Support more protocols, like IPv6. - return nil, fmt.Errorf("can't deduce the ethernet header's next protocol: %v", b) + // Assume that the rest is a payload. + nextParser = ParsePayload } + return ðer, nextParser } func (l *Ether) match(other Layer) bool { @@ -173,7 +222,7 @@ func (l *Ether) length() int { return header.EthernetMinimumSize } -// IPv4 can construct and match the ethernet excapulation. +// IPv4 can construct and match an IPv4 encapsulation. type IPv4 struct { LayerBase IHL *uint8 @@ -189,6 +238,10 @@ type IPv4 struct { DstAddr *tcpip.Address } +func (l *IPv4) String() string { + return stringLayer(l) +} + func (l *IPv4) toBytes() ([]byte, error) { b := make([]byte, header.IPv4MinimumSize) h := header.IPv4(b) @@ -236,9 +289,11 @@ func (l *IPv4) toBytes() ([]byte, error) { switch n := l.next().(type) { case *TCP: fields.Protocol = uint8(header.TCPProtocolNumber) + case *UDP: + fields.Protocol = uint8(header.UDPProtocolNumber) default: - // TODO(b/150301488): Support more protocols, like UDP. - return nil, fmt.Errorf("can't deduce the ip header's next protocol: %+v", n) + // TODO(b/150301488): Support more protocols as needed. + return nil, fmt.Errorf("ipv4 header's next layer is unrecognized: %#v", n) } } if l.SrcAddr != nil { @@ -277,7 +332,7 @@ func Address(v tcpip.Address) *tcpip.Address { // ParseIPv4 parses the bytes assuming that they start with an ipv4 header and // continues parsing further encapsulations. -func ParseIPv4(b []byte) (Layers, error) { +func ParseIPv4(b []byte) (Layer, LayerParser) { h := header.IPv4(b) tos, _ := h.TOS() ipv4 := IPv4{ @@ -293,16 +348,17 @@ func ParseIPv4(b []byte) (Layers, error) { SrcAddr: Address(h.SourceAddress()), DstAddr: Address(h.DestinationAddress()), } - layers := Layers{&ipv4} - switch h.Protocol() { - case uint8(header.TCPProtocolNumber): - moreLayers, err := ParseTCP(b[ipv4.length():]) - if err != nil { - return nil, err - } - return append(layers, moreLayers...), nil + var nextParser LayerParser + switch h.TransportProtocol() { + case header.TCPProtocolNumber: + nextParser = ParseTCP + case header.UDPProtocolNumber: + nextParser = ParseUDP + default: + // Assume that the rest is a payload. + nextParser = ParsePayload } - return nil, fmt.Errorf("can't deduce the ethernet header's next protocol: %d", h.Protocol()) + return &ipv4, nextParser } func (l *IPv4) match(other Layer) bool { @@ -316,7 +372,7 @@ func (l *IPv4) length() int { return int(*l.IHL) } -// TCP can construct and match the TCP excapulation. +// TCP can construct and match a TCP encapsulation. type TCP struct { LayerBase SrcPort *uint16 @@ -330,6 +386,10 @@ type TCP struct { UrgentPointer *uint16 } +func (l *TCP) String() string { + return stringLayer(l) +} + func (l *TCP) toBytes() ([]byte, error) { b := make([]byte, header.TCPMinimumSize) h := header.TCP(b) @@ -347,12 +407,16 @@ func (l *TCP) toBytes() ([]byte, error) { } if l.DataOffset != nil { h.SetDataOffset(*l.DataOffset) + } else { + h.SetDataOffset(uint8(l.length())) } if l.Flags != nil { h.SetFlags(*l.Flags) } if l.WindowSize != nil { h.SetWindowSize(*l.WindowSize) + } else { + h.SetWindowSize(32768) } if l.UrgentPointer != nil { h.SetUrgentPoiner(*l.UrgentPointer) @@ -361,38 +425,52 @@ func (l *TCP) toBytes() ([]byte, error) { h.SetChecksum(*l.Checksum) return h, nil } - if err := setChecksum(&h, l); err != nil { + if err := setTCPChecksum(&h, l); err != nil { return nil, err } return h, nil } -// setChecksum calculates the checksum of the TCP header and sets it in h. -func setChecksum(h *header.TCP, tcp *TCP) error { - h.SetChecksum(0) - tcpLength := uint16(tcp.length()) - current := tcp.next() - for current != nil { - tcpLength += uint16(current.length()) - current = current.next() +// totalLength returns the length of the provided layer and all following +// layers. +func totalLength(l Layer) int { + var totalLength int + for ; l != nil; l = l.next() { + totalLength += l.length() } + return totalLength +} +// layerChecksum calculates the checksum of the Layer header, including the +// peusdeochecksum of the layer before it and all the bytes after it.. +func layerChecksum(l Layer, protoNumber tcpip.TransportProtocolNumber) (uint16, error) { + totalLength := uint16(totalLength(l)) var xsum uint16 - switch s := tcp.prev().(type) { + switch s := l.prev().(type) { case *IPv4: - xsum = header.PseudoHeaderChecksum(header.TCPProtocolNumber, *s.SrcAddr, *s.DstAddr, tcpLength) + xsum = header.PseudoHeaderChecksum(protoNumber, *s.SrcAddr, *s.DstAddr, totalLength) default: // TODO(b/150301488): Support more protocols, like IPv6. - return fmt.Errorf("can't get src and dst addr from previous layer") + return 0, fmt.Errorf("can't get src and dst addr from previous layer: %#v", s) } - current = tcp.next() - for current != nil { + var payloadBytes buffer.VectorisedView + for current := l.next(); current != nil; current = current.next() { payload, err := current.toBytes() if err != nil { - return fmt.Errorf("can't get bytes for next header: %s", payload) + return 0, fmt.Errorf("can't get bytes for next header: %s", payload) } - xsum = header.Checksum(payload, xsum) - current = current.next() + payloadBytes.AppendView(payload) + } + xsum = header.ChecksumVV(payloadBytes, xsum) + return xsum, nil +} + +// setTCPChecksum calculates the checksum of the TCP header and sets it in h. +func setTCPChecksum(h *header.TCP, tcp *TCP) error { + h.SetChecksum(0) + xsum, err := layerChecksum(tcp, header.TCPProtocolNumber) + if err != nil { + return err } h.SetChecksum(^h.CalculateChecksum(xsum)) return nil @@ -406,7 +484,7 @@ func Uint32(v uint32) *uint32 { // ParseTCP parses the bytes assuming that they start with a tcp header and // continues parsing further encapsulations. -func ParseTCP(b []byte) (Layers, error) { +func ParseTCP(b []byte) (Layer, LayerParser) { h := header.TCP(b) tcp := TCP{ SrcPort: Uint16(h.SourcePort()), @@ -419,12 +497,7 @@ func ParseTCP(b []byte) (Layers, error) { Checksum: Uint16(h.Checksum()), UrgentPointer: Uint16(h.UrgentPointer()), } - layers := Layers{&tcp} - moreLayers, err := ParsePayload(b[tcp.length():]) - if err != nil { - return nil, err - } - return append(layers, moreLayers...), nil + return &tcp, ParsePayload } func (l *TCP) match(other Layer) bool { @@ -444,19 +517,101 @@ func (l *TCP) merge(other TCP) error { return mergo.Merge(l, other, mergo.WithOverride) } +// UDP can construct and match a UDP encapsulation. +type UDP struct { + LayerBase + SrcPort *uint16 + DstPort *uint16 + Length *uint16 + Checksum *uint16 +} + +func (l *UDP) String() string { + return stringLayer(l) +} + +func (l *UDP) toBytes() ([]byte, error) { + b := make([]byte, header.UDPMinimumSize) + h := header.UDP(b) + if l.SrcPort != nil { + h.SetSourcePort(*l.SrcPort) + } + if l.DstPort != nil { + h.SetDestinationPort(*l.DstPort) + } + if l.Length != nil { + h.SetLength(*l.Length) + } else { + h.SetLength(uint16(totalLength(l))) + } + if l.Checksum != nil { + h.SetChecksum(*l.Checksum) + return h, nil + } + if err := setUDPChecksum(&h, l); err != nil { + return nil, err + } + return h, nil +} + +// setUDPChecksum calculates the checksum of the UDP header and sets it in h. +func setUDPChecksum(h *header.UDP, udp *UDP) error { + h.SetChecksum(0) + xsum, err := layerChecksum(udp, header.UDPProtocolNumber) + if err != nil { + return err + } + h.SetChecksum(^h.CalculateChecksum(xsum)) + return nil +} + +// ParseUDP parses the bytes assuming that they start with a udp header and +// returns the parsed layer and the next parser to use. +func ParseUDP(b []byte) (Layer, LayerParser) { + h := header.UDP(b) + udp := UDP{ + SrcPort: Uint16(h.SourcePort()), + DstPort: Uint16(h.DestinationPort()), + Length: Uint16(h.Length()), + Checksum: Uint16(h.Checksum()), + } + return &udp, ParsePayload +} + +func (l *UDP) match(other Layer) bool { + return equalLayer(l, other) +} + +func (l *UDP) length() int { + if l.Length == nil { + return header.UDPMinimumSize + } + return int(*l.Length) +} + +// merge overrides the values in l with the values from other but only in fields +// where the value is not nil. +func (l *UDP) merge(other UDP) error { + return mergo.Merge(l, other, mergo.WithOverride) +} + // Payload has bytes beyond OSI layer 4. type Payload struct { LayerBase Bytes []byte } +func (l *Payload) String() string { + return stringLayer(l) +} + // ParsePayload parses the bytes assuming that they start with a payload and // continue to the end. There can be no further encapsulations. -func ParsePayload(b []byte) (Layers, error) { +func ParsePayload(b []byte) (Layer, LayerParser) { payload := Payload{ Bytes: b, } - return Layers{&payload}, nil + return &payload, nil } func (l *Payload) toBytes() ([]byte, error) { @@ -474,15 +629,24 @@ func (l *Payload) length() int { // Layers is an array of Layer and supports similar functions to Layer. type Layers []Layer -func (ls *Layers) toBytes() ([]byte, error) { +// linkLayers sets the linked-list ponters in ls. +func (ls *Layers) linkLayers() { for i, l := range *ls { if i > 0 { l.setPrev((*ls)[i-1]) + } else { + l.setPrev(nil) } if i+1 < len(*ls) { l.setNext((*ls)[i+1]) + } else { + l.setNext(nil) } } +} + +func (ls *Layers) toBytes() ([]byte, error) { + ls.linkLayers() outBytes := []byte{} for _, l := range *ls { layerBytes, err := l.toBytes() diff --git a/test/packetimpact/testbench/layers_test.go b/test/packetimpact/testbench/layers_test.go new file mode 100644 index 000000000..8ffc26bf9 --- /dev/null +++ b/test/packetimpact/testbench/layers_test.go @@ -0,0 +1,144 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package testbench + +import "testing" + +import "gvisor.dev/gvisor/pkg/tcpip" + +func TestLayerMatch(t *testing.T) { + var nilPayload *Payload + noPayload := &Payload{} + emptyPayload := &Payload{Bytes: []byte{}} + fullPayload := &Payload{Bytes: []byte{1, 2, 3}} + emptyTCP := &TCP{SrcPort: Uint16(1234), LayerBase: LayerBase{nextLayer: emptyPayload}} + fullTCP := &TCP{SrcPort: Uint16(1234), LayerBase: LayerBase{nextLayer: fullPayload}} + for _, tt := range []struct { + a, b Layer + want bool + }{ + {nilPayload, nilPayload, true}, + {nilPayload, noPayload, true}, + {nilPayload, emptyPayload, true}, + {nilPayload, fullPayload, true}, + {noPayload, noPayload, true}, + {noPayload, emptyPayload, true}, + {noPayload, fullPayload, true}, + {emptyPayload, emptyPayload, true}, + {emptyPayload, fullPayload, false}, + {fullPayload, fullPayload, true}, + {emptyTCP, fullTCP, true}, + } { + if got := tt.a.match(tt.b); got != tt.want { + t.Errorf("%s.match(%s) = %t, want %t", tt.a, tt.b, got, tt.want) + } + if got := tt.b.match(tt.a); got != tt.want { + t.Errorf("%s.match(%s) = %t, want %t", tt.b, tt.a, got, tt.want) + } + } +} + +func TestLayerStringFormat(t *testing.T) { + for _, tt := range []struct { + name string + l Layer + want string + }{ + { + name: "TCP", + l: &TCP{ + SrcPort: Uint16(34785), + DstPort: Uint16(47767), + SeqNum: Uint32(3452155723), + AckNum: Uint32(2596996163), + DataOffset: Uint8(5), + Flags: Uint8(20), + WindowSize: Uint16(64240), + Checksum: Uint16(0x2e2b), + }, + want: "&testbench.TCP{" + + "SrcPort:34785 " + + "DstPort:47767 " + + "SeqNum:3452155723 " + + "AckNum:2596996163 " + + "DataOffset:5 " + + "Flags:20 " + + "WindowSize:64240 " + + "Checksum:11819" + + "}", + }, + { + name: "UDP", + l: &UDP{ + SrcPort: Uint16(34785), + DstPort: Uint16(47767), + Length: Uint16(12), + }, + want: "&testbench.UDP{" + + "SrcPort:34785 " + + "DstPort:47767 " + + "Length:12" + + "}", + }, + { + name: "IPv4", + l: &IPv4{ + IHL: Uint8(5), + TOS: Uint8(0), + TotalLength: Uint16(44), + ID: Uint16(0), + Flags: Uint8(2), + FragmentOffset: Uint16(0), + TTL: Uint8(64), + Protocol: Uint8(6), + Checksum: Uint16(0x2e2b), + SrcAddr: Address(tcpip.Address([]byte{197, 34, 63, 10})), + DstAddr: Address(tcpip.Address([]byte{197, 34, 63, 20})), + }, + want: "&testbench.IPv4{" + + "IHL:5 " + + "TOS:0 " + + "TotalLength:44 " + + "ID:0 " + + "Flags:2 " + + "FragmentOffset:0 " + + "TTL:64 " + + "Protocol:6 " + + "Checksum:11819 " + + "SrcAddr:197.34.63.10 " + + "DstAddr:197.34.63.20" + + "}", + }, + { + name: "Ether", + l: &Ether{ + SrcAddr: LinkAddress(tcpip.LinkAddress([]byte{0x02, 0x42, 0xc5, 0x22, 0x3f, 0x0a})), + DstAddr: LinkAddress(tcpip.LinkAddress([]byte{0x02, 0x42, 0xc5, 0x22, 0x3f, 0x14})), + Type: NetworkProtocolNumber(4), + }, + want: "&testbench.Ether{" + + "SrcAddr:02:42:c5:22:3f:0a " + + "DstAddr:02:42:c5:22:3f:14 " + + "Type:4" + + "}", + }, + } { + t.Run(tt.name, func(t *testing.T) { + if got := tt.l.String(); got != tt.want { + t.Errorf("%s.String() = %s, want: %s", tt.name, got, tt.want) + } + }) + } +} diff --git a/test/packetimpact/testbench/rawsockets.go b/test/packetimpact/testbench/rawsockets.go index 0c7d0f979..0074484f7 100644 --- a/test/packetimpact/testbench/rawsockets.go +++ b/test/packetimpact/testbench/rawsockets.go @@ -47,6 +47,12 @@ func NewSniffer(t *testing.T) (Sniffer, error) { if err != nil { return Sniffer{}, err } + if err := unix.SetsockoptInt(snifferFd, unix.SOL_SOCKET, unix.SO_RCVBUFFORCE, 1); err != nil { + t.Fatalf("can't set sockopt SO_RCVBUFFORCE to 1: %s", err) + } + if err := unix.SetsockoptInt(snifferFd, unix.SOL_SOCKET, unix.SO_RCVBUF, 1e7); err != nil { + t.Fatalf("can't setsockopt SO_RCVBUF to 10M: %s", err) + } return Sniffer{ t: t, fd: snifferFd, |