Replace test_runner.sh bash script with Go.

PiperOrigin-RevId: 311285868

1 files changed, 315 insertions, 0 deletions

diff --git a/test/packetimpact/runner/packetimpact_test.go b/test/packetimpact/runner/packetimpact_test.go
new file mode 100644
index 000000000..8996f23fa
--- /dev/null
+++ b/test/packetimpact/runner/packetimpact_test.go
@@ -0,0 +1,315 @@
+// 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.
+
+// The runner starts docker containers and networking for a packetimpact test.
+package packetimpact_test
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"math/rand"
+	"net"
+	"os"
+	"os/exec"
+	"path"
+	"strings"
+	"testing"
+	"time"
+
+	"gvisor.dev/gvisor/pkg/test/dockerutil"
+	"gvisor.dev/gvisor/test/packetimpact/netdevs"
+)
+
+// stringList implements flag.Value.
+type stringList []string
+
+// String implements flag.Value.String.
+func (l *stringList) String() string {
+	return strings.Join(*l, ",")
+}
+
+// Set implements flag.Value.Set.
+func (l *stringList) Set(value string) error {
+	*l = append(*l, value)
+	return nil
+}
+
+var (
+	dutPlatform     = flag.String("dut_platform", "", "either \"linux\" or \"netstack\"")
+	testbenchBinary = flag.String("testbench_binary", "", "path to the testbench binary")
+	tshark          = flag.Bool("tshark", false, "use more verbose tshark in logs instead of tcpdump")
+	extraTestArgs   = stringList{}
+	expectFailure   = flag.Bool("expect_failure", false, "expect that the test will fail when run")
+
+	dutAddr       = net.IPv4(0, 0, 0, 10)
+	testbenchAddr = net.IPv4(0, 0, 0, 20)
+)
+
+const ctrlPort = "40000"
+
+// logger implements testutil.Logger.
+//
+// Labels logs based on their source and formats multi-line logs.
+type logger string
+
+// Name implements testutil.Logger.Name.
+func (l logger) Name() string {
+	return string(l)
+}
+
+// Logf implements testutil.Logger.Logf.
+func (l logger) Logf(format string, args ...interface{}) {
+	lines := strings.Split(fmt.Sprintf(format, args...), "\n")
+	log.Printf("%s: %s", l, lines[0])
+	for _, line := range lines[1:] {
+		log.Printf("%*s  %s", len(l), "", line)
+	}
+}
+
+func TestOne(t *testing.T) {
+	flag.Var(&extraTestArgs, "extra_test_arg", "extra arguments to pass to the testbench")
+	flag.Parse()
+	if *dutPlatform != "linux" && *dutPlatform != "netstack" {
+		t.Fatal("--dut_platform should be either linux or netstack")
+	}
+	if *testbenchBinary == "" {
+		t.Fatal("--testbench_binary is missing")
+	}
+	if *dutPlatform == "netstack" {
+		if _, err := dockerutil.RuntimePath(); err != nil {
+			t.Fatal("--runtime is missing or invalid with --dut_platform=netstack:", err)
+		}
+	}
+	dockerutil.EnsureSupportedDockerVersion()
+
+	// Create the networks needed for the test. One control network is needed for
+	// the gRPC control packets and one test network on which to transmit the test
+	// packets.
+	ctrlNet := dockerutil.NewDockerNetwork(logger("ctrlNet"))
+	testNet := dockerutil.NewDockerNetwork(logger("testNet"))
+	for _, dn := range []*dockerutil.DockerNetwork{ctrlNet, testNet} {
+		for {
+			if err := createDockerNetwork(dn); err != nil {
+				t.Log("creating docker network:", err)
+				const wait = 100 * time.Millisecond
+				t.Logf("sleeping %s and will try creating docker network again", wait)
+				// This can fail if another docker network claimed the same IP so we'll
+				// just try again.
+				time.Sleep(wait)
+				continue
+			}
+			break
+		}
+		defer func(dn *dockerutil.DockerNetwork) {
+			if err := dn.Cleanup(); err != nil {
+				t.Errorf("unable to cleanup container %s: %s", dn.Name, err)
+			}
+		}(dn)
+	}
+
+	runOpts := dockerutil.RunOpts{
+		Image:      "packetimpact",
+		CapAdd:     []string{"NET_ADMIN"},
+		Extra:      []string{"--sysctl", "net.ipv6.conf.all.disable_ipv6=0", "--rm"},
+		Foreground: true,
+		Pty:        func(_ *exec.Cmd, _ *os.File) {},
+	}
+
+	// Create the Docker container for the DUT.
+	dut := dockerutil.MakeDocker(logger("dut"))
+	if *dutPlatform == "linux" {
+		dut.Runtime = ""
+	}
+
+	const containerPosixServerBinary = "/packetimpact/posix_server"
+	dut.CopyFiles("/packetimpact", "/test/packetimpact/dut/posix_server")
+
+	if err := dut.Create(runOpts, containerPosixServerBinary, "--ip=0.0.0.0", "--port="+ctrlPort); err != nil {
+		t.Fatalf("unable to create container %s: %s", dut.Name, err)
+	}
+	defer dut.CleanUp()
+
+	// Add ctrlNet as eth1 and testNet as eth2.
+	const testNetDev = "eth2"
+	if err := addNetworks(dut, dutAddr, []*dockerutil.DockerNetwork{ctrlNet, testNet}); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := dut.Start(); err != nil {
+		t.Fatalf("unable to start container %s: %s", dut.Name, err)
+	}
+
+	if _, err := dut.WaitForOutput("Server listening.*\n", 60*time.Second); err != nil {
+		t.Fatalf("%s on container %s never listened: %s", containerPosixServerBinary, dut.Name, err)
+	}
+
+	dutTestDevice, dutDeviceInfo, err := deviceByIP(dut, addressInSubnet(dutAddr, *testNet.Subnet))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	remoteMAC := dutDeviceInfo.MAC
+	remoteIPv6 := dutDeviceInfo.IPv6Addr
+	// Netstack as DUT doesn't assign IPv6 addresses automatically so do it if
+	// needed.
+	if remoteIPv6 == nil {
+		if _, err := dut.Exec(dockerutil.RunOpts{}, "ip", "addr", "add", netdevs.MACToIP(remoteMAC).String(), "scope", "link", "dev", dutTestDevice); err != nil {
+			t.Fatalf("unable to ip addr add on container %s: %s", dut.Name, err)
+		}
+		// Now try again, to make sure that it worked.
+		_, dutDeviceInfo, err = deviceByIP(dut, addressInSubnet(dutAddr, *testNet.Subnet))
+		if err != nil {
+			t.Fatal(err)
+		}
+		remoteIPv6 = dutDeviceInfo.IPv6Addr
+		if remoteIPv6 == nil {
+			t.Fatal("unable to set IPv6 address on container", dut.Name)
+		}
+	}
+
+	// Create the Docker container for the testbench.
+	testbench := dockerutil.MakeDocker(logger("testbench"))
+	testbench.Runtime = "" // The testbench always runs on Linux.
+
+	tbb := path.Base(*testbenchBinary)
+	containerTestbenchBinary := "/packetimpact/" + tbb
+	testbench.CopyFiles("/packetimpact", "/test/packetimpact/tests/"+tbb)
+
+	// Run tcpdump in the test bench unbuffered, without DNS resolution, just on
+	// the interface with the test packets.
+	snifferArgs := []string{
+		"tcpdump", "-S", "-vvv", "-U", "-n", "-i", testNetDev,
+	}
+	snifferRegex := "tcpdump: listening.*\n"
+	if *tshark {
+		// Run tshark in the test bench unbuffered, without DNS resolution, just on
+		// the interface with the test packets.
+		snifferArgs = []string{
+			"tshark", "-V", "-l", "-n", "-i", testNetDev,
+			"-o", "tcp.check_checksum:TRUE",
+			"-o", "udp.check_checksum:TRUE",
+		}
+		snifferRegex = "Capturing on.*\n"
+	}
+
+	if err := testbench.Create(runOpts, snifferArgs...); err != nil {
+		t.Fatalf("unable to create container %s: %s", testbench.Name, err)
+	}
+	defer testbench.CleanUp()
+
+	// Add ctrlNet as eth1 and testNet as eth2.
+	if err := addNetworks(testbench, testbenchAddr, []*dockerutil.DockerNetwork{ctrlNet, testNet}); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := testbench.Start(); err != nil {
+		t.Fatalf("unable to start container %s: %s", testbench.Name, err)
+	}
+
+	// Kill so that it will flush output.
+	defer testbench.Exec(dockerutil.RunOpts{}, "killall", snifferArgs[0])
+
+	if _, err := testbench.WaitForOutput(snifferRegex, 60*time.Second); err != nil {
+		t.Fatalf("sniffer on %s never listened: %s", dut.Name, err)
+	}
+
+	// Because the Linux kernel receives the SYN-ACK but didn't send the SYN it
+	// will issue a RST. To prevent this IPtables can be used to filter out all
+	// incoming packets. The raw socket that packetimpact tests use will still see
+	// everything.
+	if _, err := testbench.Exec(dockerutil.RunOpts{}, "iptables", "-A", "INPUT", "-i", testNetDev, "-j", "DROP"); err != nil {
+		t.Fatalf("unable to Exec iptables on container %s: %s", testbench.Name, err)
+	}
+
+	// FIXME(b/156449515): Some piece of the system has a race. The old
+	// bash script version had a sleep, so we have one too. The race should
+	// be fixed and this sleep removed.
+	time.Sleep(time.Second)
+
+	// Start a packetimpact test on the test bench. The packetimpact test sends
+	// and receives packets and also sends POSIX socket commands to the
+	// posix_server to be executed on the DUT.
+	testArgs := []string{containerTestbenchBinary}
+	testArgs = append(testArgs, extraTestArgs...)
+	testArgs = append(testArgs,
+		"--posix_server_ip", addressInSubnet(dutAddr, *ctrlNet.Subnet).String(),
+		"--posix_server_port", ctrlPort,
+		"--remote_ipv4", addressInSubnet(dutAddr, *testNet.Subnet).String(),
+		"--local_ipv4", addressInSubnet(testbenchAddr, *testNet.Subnet).String(),
+		"--remote_ipv6", remoteIPv6.String(),
+		"--remote_mac", remoteMAC.String(),
+		"--device", testNetDev,
+	)
+	_, err = testbench.Exec(dockerutil.RunOpts{}, testArgs...)
+	if !*expectFailure && err != nil {
+		t.Fatal("test failed:", err)
+	}
+	if *expectFailure && err == nil {
+		t.Fatal("test failure expected but the test succeeded, enable the test and mark the corresponding bug as fixed")
+	}
+}
+
+func addNetworks(d *dockerutil.Docker, addr net.IP, networks []*dockerutil.DockerNetwork) error {
+	for _, dn := range networks {
+		ip := addressInSubnet(addr, *dn.Subnet)
+		// Connect to the network with the specified IP address.
+		if err := dn.Connect(d, "--ip", ip.String()); err != nil {
+			return fmt.Errorf("unable to connect container %s to network %s: %w", d.Name, dn.Name, err)
+		}
+	}
+	return nil
+}
+
+// addressInSubnet combines the subnet provided with the address and returns a
+// new address. The return address bits come from the subnet where the mask is 1
+// and from the ip address where the mask is 0.
+func addressInSubnet(addr net.IP, subnet net.IPNet) net.IP {
+	var octets []byte
+	for i := 0; i < 4; i++ {
+		octets = append(octets, (subnet.IP.To4()[i]&subnet.Mask[i])+(addr.To4()[i]&(^subnet.Mask[i])))
+	}
+	return net.IP(octets)
+}
+
+// makeDockerNetwork makes a randomly-named network that will start with the
+// namePrefix. The network will be a random /24 subnet.
+func createDockerNetwork(n *dockerutil.DockerNetwork) error {
+	randSource := rand.NewSource(time.Now().UnixNano())
+	r1 := rand.New(randSource)
+	// Class C, 192.0.0.0 to 223.255.255.255, transitionally has mask 24.
+	ip := net.IPv4(byte(r1.Intn(224-192)+192), byte(r1.Intn(256)), byte(r1.Intn(256)), 0)
+	n.Subnet = &net.IPNet{
+		IP:   ip,
+		Mask: ip.DefaultMask(),
+	}
+	return n.Create()
+}
+
+// deviceByIP finds a deviceInfo and device name from an IP address.
+func deviceByIP(d *dockerutil.Docker, ip net.IP) (string, netdevs.DeviceInfo, error) {
+	out, err := d.Exec(dockerutil.RunOpts{}, "ip", "addr", "show")
+	if err != nil {
+		return "", netdevs.DeviceInfo{}, fmt.Errorf("listing devices on %s container: %w", d.Name, err)
+	}
+	devs, err := netdevs.ParseDevices(out)
+	if err != nil {
+		return "", netdevs.DeviceInfo{}, fmt.Errorf("parsing devices from %s container: %w", d.Name, err)
+	}
+	testDevice, deviceInfo, err := netdevs.FindDeviceByIP(ip, devs)
+	if err != nil {
+		return "", netdevs.DeviceInfo{}, fmt.Errorf("can't find deviceInfo for container %s: %w", d.Name, err)
+	}
+	return testDevice, deviceInfo, nil
+}