Add UDP send/recv packetimpact tests.

Fixes #2654

PiperOrigin-RevId: 310642216

2 files changed, 105 insertions, 0 deletions

diff --git a/test/packetimpact/tests/BUILD b/test/packetimpact/tests/BUILD
index 563823d04..c25b3b8c1 100644
--- a/test/packetimpact/tests/BUILD
+++ b/test/packetimpact/tests/BUILD
@@ -148,6 +148,15 @@ packetimpact_go_test(
     ],
 )
 
+packetimpact_go_test(
+    name = "udp_send_recv_dgram",
+    srcs = ["udp_send_recv_dgram_test.go"],
+    deps = [
+        "//test/packetimpact/testbench",
+        "@org_golang_x_sys//unix:go_default_library",
+    ],
+)
+
 sh_binary(
     name = "test_runner",
     srcs = ["test_runner.sh"],
diff --git a/test/packetimpact/tests/udp_send_recv_dgram_test.go b/test/packetimpact/tests/udp_send_recv_dgram_test.go
new file mode 100644
index 000000000..1c682831c
--- /dev/null
+++ b/test/packetimpact/tests/udp_send_recv_dgram_test.go
@@ -0,0 +1,96 @@
+// 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 udp_send_recv_dgram_test
+
+import (
+	"math/rand"
+	"net"
+	"testing"
+	"time"
+
+	"golang.org/x/sys/unix"
+	tb "gvisor.dev/gvisor/test/packetimpact/testbench"
+)
+
+func generateRandomPayload(t *testing.T, n int) string {
+	t.Helper()
+	buf := make([]byte, n)
+	if _, err := rand.Read(buf); err != nil {
+		t.Fatalf("rand.Read(buf) failed: %s", err)
+	}
+	return string(buf)
+}
+
+func TestUDPRecv(t *testing.T) {
+	dut := tb.NewDUT(t)
+	defer dut.TearDown()
+	boundFD, remotePort := dut.CreateBoundSocket(unix.SOCK_DGRAM, unix.IPPROTO_UDP, net.ParseIP("0.0.0.0"))
+	defer dut.Close(boundFD)
+	conn := tb.NewUDPIPv4(t, tb.UDP{DstPort: &remotePort}, tb.UDP{SrcPort: &remotePort})
+	defer conn.Close()
+
+	testCases := []struct {
+		name    string
+		payload string
+	}{
+		{"emptypayload", ""},
+		{"small payload", "hello world"},
+		{"1kPayload", generateRandomPayload(t, 1<<10)},
+		// Even though UDP allows larger dgrams we don't test it here as
+		// they need to be fragmented and written out as individual
+		// frames.
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			frame := conn.CreateFrame(&tb.UDP{}, &tb.Payload{Bytes: []byte(tc.payload)})
+			conn.SendFrame(frame)
+			if got, want := string(dut.Recv(boundFD, int32(len(tc.payload)), 0)), tc.payload; got != want {
+				t.Fatalf("received payload does not match sent payload got: %s, want: %s", got, want)
+			}
+		})
+	}
+}
+
+func TestUDPSend(t *testing.T) {
+	dut := tb.NewDUT(t)
+	defer dut.TearDown()
+	boundFD, remotePort := dut.CreateBoundSocket(unix.SOCK_DGRAM, unix.IPPROTO_UDP, net.ParseIP("0.0.0.0"))
+	defer dut.Close(boundFD)
+	conn := tb.NewUDPIPv4(t, tb.UDP{DstPort: &remotePort}, tb.UDP{SrcPort: &remotePort})
+	defer conn.Close()
+
+	testCases := []struct {
+		name    string
+		payload string
+	}{
+		{"emptypayload", ""},
+		{"small payload", "hello world"},
+		{"1kPayload", generateRandomPayload(t, 1<<10)},
+		// Even though UDP allows larger dgrams we don't test it here as
+		// they need to be fragmented and written out as individual
+		// frames.
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			conn.Drain()
+			if got, want := int(dut.SendTo(boundFD, []byte(tc.payload), 0, conn.LocalAddr())), len(tc.payload); got != want {
+				t.Fatalf("short write got: %d, want: %d", got, want)
+			}
+			if _, err := conn.ExpectData(tb.UDP{SrcPort: &remotePort}, tb.Payload{Bytes: []byte(tc.payload)}, 1*time.Second); err != nil {
+				t.Fatal(err)
+			}
+		})
+	}
+}