Cleanup device name confusion in packetimpact testbench

There are two device names on the test net.
- The sniffer/injector device which is always a linux device. Only the
testbench library is interested in this device.
- The device which is on the DUT. It happens to be the same device as
the former if DUT is linux. An individual test might be interested in
this device if the test cares about the device name.

PiperOrigin-RevId: 332112968

1 files changed, 10 insertions, 5 deletions

diff --git a/test/packetimpact/runner/dut.go b/test/packetimpact/runner/dut.go
index d4c486f9c..96a0fb6c8 100644
--- a/test/packetimpact/runner/dut.go
+++ b/test/packetimpact/runner/dut.go
@@ -172,7 +172,7 @@ func TestWithDUT(ctx context.Context, t *testing.T, mkDevice func(*dockerutil.Co
 	}
 
 	device := mkDevice(dut)
-	remoteIPv6, remoteMAC, dutDeviceID, testNetDev := device.Prepare(ctx, t, runOpts, ctrlNet, testNet, containerAddr)
+	remoteIPv6, remoteMAC, dutDeviceID, dutTestNetDev := device.Prepare(ctx, t, runOpts, ctrlNet, testNet, containerAddr)
 
 	// Create the Docker container for the testbench.
 	testbench := dockerutil.MakeNativeContainer(ctx, logger("testbench"))
@@ -181,12 +181,16 @@ func TestWithDUT(ctx context.Context, t *testing.T, mkDevice func(*dockerutil.Co
 	containerTestbenchBinary := filepath.Join("/packetimpact", tbb)
 	testbench.CopyFiles(&runOpts, "/packetimpact", filepath.Join("test/packetimpact/tests", tbb))
 
+	// snifferNetDev is a network device on the test orchestrator that we will
+	// run sniffer (tcpdump or tshark) on and inject traffic to, not to be
+	// confused with the device on the DUT.
+	const snifferNetDev = "eth2"
 	// 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,
+		"-i", snifferNetDev,
 		"-w", testOutputDir + "/dump.pcap",
 	}
 	snifferRegex := "tcpdump: listening.*\n"
@@ -194,7 +198,7 @@ func TestWithDUT(ctx context.Context, t *testing.T, mkDevice func(*dockerutil.Co
 		// 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,
+			"tshark", "-V", "-l", "-n", "-i", snifferNetDev,
 			"-o", "tcp.check_checksum:TRUE",
 			"-o", "udp.check_checksum:TRUE",
 		}
@@ -228,7 +232,7 @@ func TestWithDUT(ctx context.Context, t *testing.T, mkDevice func(*dockerutil.Co
 	// this, we can install the following iptables rules. The raw socket that
 	// packetimpact tests use will still be able to see everything.
 	for _, bin := range []string{"iptables", "ip6tables"} {
-		if logs, err := testbench.Exec(ctx, dockerutil.ExecOpts{}, bin, "-A", "INPUT", "-i", testNetDev, "-p", "tcp", "-j", "DROP"); err != nil {
+		if logs, err := testbench.Exec(ctx, dockerutil.ExecOpts{}, bin, "-A", "INPUT", "-i", snifferNetDev, "-p", "tcp", "-j", "DROP"); err != nil {
 			t.Fatalf("unable to Exec %s on container %s: %s, logs from testbench:\n%s", bin, testbench.Name, err, logs)
 		}
 	}
@@ -251,7 +255,8 @@ func TestWithDUT(ctx context.Context, t *testing.T, mkDevice func(*dockerutil.Co
 		"--remote_ipv6", remoteIPv6.String(),
 		"--remote_mac", remoteMAC.String(),
 		"--remote_interface_id", fmt.Sprintf("%d", dutDeviceID),
-		"--device", testNetDev,
+		"--local_device", snifferNetDev,
+		"--remote_device", dutTestNetDev,
 		fmt.Sprintf("--native=%t", native),
 	)
 	testbenchLogs, err := testbench.Exec(ctx, dockerutil.ExecOpts{}, testArgs...)