From 9c496ddd1966c8ac35d0b404760d04bcae958291 Mon Sep 17 00:00:00 2001
From: Marten Seemann <martenseemann@gmail.com>
Date: Mon, 1 Jul 2019 10:51:09 +0700
Subject: [PATCH] add an integration test that sends invalid packets

---
 integrationtests/self/mitm_test.go | 164 +++++++++++++++++++++++++++++
 1 file changed, 164 insertions(+)
 create mode 100644 integrationtests/self/mitm_test.go

diff --git a/integrationtests/self/mitm_test.go b/integrationtests/self/mitm_test.go
new file mode 100644
index 00000000..c305769a
--- /dev/null
+++ b/integrationtests/self/mitm_test.go
@@ -0,0 +1,164 @@
+package self_test
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io/ioutil"
+	"math"
+	mrand "math/rand"
+	"net"
+	"time"
+
+	quic "github.com/lucas-clemente/quic-go"
+	quicproxy "github.com/lucas-clemente/quic-go/integrationtests/tools/proxy"
+	"github.com/lucas-clemente/quic-go/integrationtests/tools/testserver"
+	"github.com/lucas-clemente/quic-go/internal/protocol"
+	"github.com/lucas-clemente/quic-go/internal/wire"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("MITM test", func() {
+	for _, v := range protocol.SupportedVersions {
+		version := v
+
+		Context(fmt.Sprintf("with QUIC version %s", version), func() {
+			const connIDLen = 6 // explicitly set the connection ID length, so the proxy can parse it
+
+			var (
+				proxy                  *quicproxy.QuicProxy
+				serverConn, clientConn *net.UDPConn
+			)
+
+			startServerAndProxy := func(delayCb quicproxy.DelayCallback) {
+				addr, err := net.ResolveUDPAddr("udp", "localhost:0")
+				Expect(err).ToNot(HaveOccurred())
+				serverConn, err = net.ListenUDP("udp", addr)
+				Expect(err).ToNot(HaveOccurred())
+				ln, err := quic.Listen(
+					serverConn,
+					getTLSConfig(),
+					&quic.Config{
+						Versions:           []protocol.VersionNumber{version},
+						ConnectionIDLength: connIDLen,
+					},
+				)
+				Expect(err).ToNot(HaveOccurred())
+				go func() {
+					defer GinkgoRecover()
+					sess, err := ln.Accept(context.Background())
+					Expect(err).ToNot(HaveOccurred())
+					str, err := sess.OpenUniStream()
+					Expect(err).ToNot(HaveOccurred())
+					_, err = str.Write(testserver.PRData)
+					Expect(err).ToNot(HaveOccurred())
+					Expect(str.Close()).To(Succeed())
+				}()
+				serverPort := ln.Addr().(*net.UDPAddr).Port
+				proxy, err = quicproxy.NewQuicProxy("localhost:0", &quicproxy.Opts{
+					RemoteAddr:  fmt.Sprintf("localhost:%d", serverPort),
+					DelayPacket: delayCb,
+				})
+				Expect(err).ToNot(HaveOccurred())
+			}
+
+			BeforeEach(func() {
+				addr, err := net.ResolveUDPAddr("udp", "localhost:0")
+				Expect(err).ToNot(HaveOccurred())
+				clientConn, err = net.ListenUDP("udp", addr)
+				Expect(err).ToNot(HaveOccurred())
+			})
+
+			AfterEach(func() {
+				// Test shutdown is tricky due to the proxy. Just wait for a bit.
+				time.Sleep(50 * time.Millisecond)
+				Expect(clientConn.Close()).To(Succeed())
+				Expect(serverConn.Close()).To(Succeed())
+				Expect(proxy.Close()).To(Succeed())
+			})
+
+			Context("injecting invalid packets", func() {
+				const rtt = 20 * time.Millisecond
+
+				sendRandomPacketsOfSameType := func(conn net.PacketConn, remoteAddr net.Addr, raw []byte) {
+					defer GinkgoRecover()
+					hdr, _, _, err := wire.ParsePacket(raw, connIDLen)
+					Expect(err).ToNot(HaveOccurred())
+					replyHdr := &wire.ExtendedHeader{
+						Header: wire.Header{
+							IsLongHeader:     hdr.IsLongHeader,
+							DestConnectionID: hdr.DestConnectionID,
+							SrcConnectionID:  hdr.SrcConnectionID,
+							Type:             hdr.Type,
+							Version:          hdr.Version,
+						},
+						PacketNumber:    protocol.PacketNumber(mrand.Int31n(math.MaxInt32 / 4)),
+						PacketNumberLen: protocol.PacketNumberLen(mrand.Int31n(4) + 1),
+					}
+
+					const numPackets = 10
+					ticker := time.NewTicker(rtt / numPackets)
+					for i := 0; i < numPackets; i++ {
+						payloadLen := mrand.Int31n(100)
+						replyHdr.Length = protocol.ByteCount(mrand.Int31n(payloadLen + 1))
+						buf := &bytes.Buffer{}
+						Expect(replyHdr.Write(buf, v)).To(Succeed())
+						b := make([]byte, payloadLen)
+						mrand.Read(b)
+						buf.Write(b)
+						if _, err := conn.WriteTo(buf.Bytes(), remoteAddr); err != nil {
+							return
+						}
+						<-ticker.C
+					}
+				}
+
+				runTest := func(delayCb quicproxy.DelayCallback) {
+					startServerAndProxy(delayCb)
+					raddr, err := net.ResolveUDPAddr("udp", fmt.Sprintf("localhost:%d", proxy.LocalPort()))
+					Expect(err).ToNot(HaveOccurred())
+					sess, err := quic.Dial(
+						clientConn,
+						raddr,
+						fmt.Sprintf("localhost:%d", proxy.LocalPort()),
+						getTLSClientConfig(),
+						&quic.Config{
+							Versions:           []protocol.VersionNumber{version},
+							ConnectionIDLength: connIDLen,
+						},
+					)
+					Expect(err).ToNot(HaveOccurred())
+					str, err := sess.AcceptUniStream(context.Background())
+					Expect(err).ToNot(HaveOccurred())
+					data, err := ioutil.ReadAll(str)
+					Expect(err).ToNot(HaveOccurred())
+					Expect(data).To(Equal(testserver.PRData))
+					Expect(sess.Close()).To(Succeed())
+				}
+
+				It("downloads a message when the packets are injected towards the server", func() {
+					delayCb := func(dir quicproxy.Direction, raw []byte) time.Duration {
+						if dir == quicproxy.DirectionIncoming {
+							defer GinkgoRecover()
+							go sendRandomPacketsOfSameType(clientConn, serverConn.LocalAddr(), raw)
+						}
+						return rtt / 2
+					}
+					runTest(delayCb)
+				})
+
+				It("downloads a message when the packets are injected towards the client", func() {
+					delayCb := func(dir quicproxy.Direction, raw []byte) time.Duration {
+						if dir == quicproxy.DirectionOutgoing {
+							defer GinkgoRecover()
+							go sendRandomPacketsOfSameType(serverConn, clientConn.LocalAddr(), raw)
+						}
+						return rtt / 2
+					}
+					runTest(delayCb)
+				})
+			})
+		})
+	}
+})