diff options
Diffstat (limited to 'test/packetimpact/tests')
-rw-r--r-- | test/packetimpact/tests/BUILD | 10 | ||||
-rw-r--r-- | test/packetimpact/tests/tcp_rcv_buf_space_test.go | 80 |
2 files changed, 90 insertions, 0 deletions
diff --git a/test/packetimpact/tests/BUILD b/test/packetimpact/tests/BUILD index fbfea61e1..94731c64b 100644 --- a/test/packetimpact/tests/BUILD +++ b/test/packetimpact/tests/BUILD @@ -340,3 +340,13 @@ packetimpact_go_test( "@org_golang_x_sys//unix:go_default_library", ], ) + +packetimpact_go_test( + name = "tcp_rcv_buf_space", + srcs = ["tcp_rcv_buf_space_test.go"], + deps = [ + "//pkg/tcpip/header", + "//test/packetimpact/testbench", + "@org_golang_x_sys//unix:go_default_library", + ], +) diff --git a/test/packetimpact/tests/tcp_rcv_buf_space_test.go b/test/packetimpact/tests/tcp_rcv_buf_space_test.go new file mode 100644 index 000000000..cfbba1e8e --- /dev/null +++ b/test/packetimpact/tests/tcp_rcv_buf_space_test.go @@ -0,0 +1,80 @@ +// 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 tcp_rcv_buf_space_test + +import ( + "context" + "flag" + "syscall" + "testing" + + "golang.org/x/sys/unix" + "gvisor.dev/gvisor/pkg/tcpip/header" + "gvisor.dev/gvisor/test/packetimpact/testbench" +) + +func init() { + testbench.RegisterFlags(flag.CommandLine) +} + +// TestReduceRecvBuf tests that a packet within window is still dropped +// if the available buffer space drops below the size of the incoming +// segment. +func TestReduceRecvBuf(t *testing.T) { + dut := testbench.NewDUT(t) + defer dut.TearDown() + listenFd, remotePort := dut.CreateListener(t, unix.SOCK_STREAM, unix.IPPROTO_TCP, 1) + defer dut.Close(t, listenFd) + conn := testbench.NewTCPIPv4(t, testbench.TCP{DstPort: &remotePort}, testbench.TCP{SrcPort: &remotePort}) + defer conn.Close(t) + + conn.Connect(t) + acceptFd, _ := dut.Accept(t, listenFd) + defer dut.Close(t, acceptFd) + + // Set a small receive buffer for the test. + const rcvBufSz = 4096 + dut.SetSockOptInt(t, acceptFd, unix.SOL_SOCKET, unix.SO_RCVBUF, rcvBufSz) + + // Retrieve the actual buffer. + bufSz := dut.GetSockOptInt(t, acceptFd, unix.SOL_SOCKET, unix.SO_RCVBUF) + + // Generate a payload of 1 more than the actual buffer size used by the + // DUT. + sampleData := testbench.GenerateRandomPayload(t, int(bufSz)+1) + // Send and receive sample data to the dut. + const pktSize = 1400 + for payload := sampleData; len(payload) != 0; { + payloadBytes := pktSize + if l := len(payload); l < payloadBytes { + payloadBytes = l + } + + conn.Send(t, testbench.TCP{Flags: testbench.Uint8(header.TCPFlagAck)}, []testbench.Layer{&testbench.Payload{Bytes: payload[:payloadBytes]}}...) + payload = payload[payloadBytes:] + } + + // First read should read < len(sampleData) + if ret, _, err := dut.RecvWithErrno(context.Background(), t, acceptFd, int32(len(sampleData)), 0); ret == -1 || int(ret) == len(sampleData) { + t.Fatalf("dut.RecvWithErrno(ctx, t, %d, %d, 0) = %d,_, %s", acceptFd, int32(len(sampleData)), ret, err) + } + + // Second read should return EAGAIN as the last segment should have been + // dropped due to it exceeding the receive buffer space available in the + // socket. + if ret, got, err := dut.RecvWithErrno(context.Background(), t, acceptFd, int32(len(sampleData)), syscall.MSG_DONTWAIT); got != nil || ret != -1 || err != syscall.EAGAIN { + t.Fatalf("expected no packets but got: %s", got) + } +} |