新增dnst隧道

internal/util/dns/conn_test.go

@@ -0,0 +1,61 @@
+package dns
+
+import (
+	"bytes"
+	"net"
+	"testing"
+	"time"
+)
+
+func TestPacketConnRoundTrip(t *testing.T) {
+	serverPC, err := net.ListenPacket("udp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer serverPC.Close()
+
+	clientPC, err := net.ListenPacket("udp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer clientPC.Close()
+
+	server := ServerConn(serverPC, DomainOption("tunnel.example."))
+	client := ClientConn(clientPC, DomainOption("tunnel.example."))
+	_ = server.SetDeadline(time.Now().Add(3 * time.Second))
+	_ = client.SetDeadline(time.Now().Add(3 * time.Second))
+
+	requestPayload := []byte("hello over dns")
+	if n, err := client.WriteTo(requestPayload, server.LocalAddr()); err != nil {
+		t.Fatal(err)
+	} else if n != len(requestPayload) {
+		t.Fatalf("client WriteTo wrote %d bytes, want %d", n, len(requestPayload))
+	}
+
+	buf := make([]byte, 1500)
+	n, clientAddr, err := server.ReadFrom(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := buf[:n]; !bytes.Equal(got, requestPayload) {
+		t.Fatalf("server ReadFrom got %q, want %q", got, requestPayload)
+	}
+
+	responsePayload := []byte("world over dns")
+	if n, err := server.WriteTo(responsePayload, clientAddr); err != nil {
+		t.Fatal(err)
+	} else if n != len(responsePayload) {
+		t.Fatalf("server WriteTo wrote %d bytes, want %d", n, len(responsePayload))
+	}
+
+	n, serverAddr, err := client.ReadFrom(buf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if serverAddr.String() != server.LocalAddr().String() {
+		t.Fatalf("response addr = %v, want %v", serverAddr, server.LocalAddr())
+	}
+	if got := buf[:n]; !bytes.Equal(got, responsePayload) {
+		t.Fatalf("client ReadFrom got %q, want %q", got, responsePayload)
+	}
+}