Migrates QUIC sessions to a new network when old network is (about to be) disconnected.

net/quic/quic_chromium_client_session_test.cc

Index: net/quic/quic_chromium_client_session_test.cc
diff --git a/net/quic/quic_chromium_client_session_test.cc b/net/quic/quic_chromium_client_session_test.cc
index ba831efa0c48428763395b3634873c1f1364bef6..356b69a69efc6b7ceb852635147bc52e0ae772f1 100644
--- a/net/quic/quic_chromium_client_session_test.cc
+++ b/net/quic/quic_chromium_client_session_test.cc
@@ -22,13 +22,19 @@
 #include "net/quic/crypto/quic_decrypter.h"
 #include "net/quic/crypto/quic_encrypter.h"
 #include "net/quic/crypto/quic_server_info.h"
+#include "net/quic/quic_connection_helper.h"
 #include "net/quic/quic_crypto_client_stream_factory.h"
+#include "net/quic/quic_default_packet_writer.h"
 #include "net/quic/quic_flags.h"
+#include "net/quic/quic_http_utils.h"
 #include "net/quic/quic_packet_reader.h"
+#include "net/quic/quic_packet_writer.h"
 #include "net/quic/quic_protocol.h"
 #include "net/quic/test_tools/crypto_test_utils.h"
+#include "net/quic/test_tools/mock_crypto_client_stream_factory.h"
 #include "net/quic/test_tools/quic_chromium_client_session_peer.h"
 #include "net/quic/test_tools/quic_spdy_session_peer.h"
+#include "net/quic/test_tools/quic_test_packet_maker.h"
 #include "net/quic/test_tools/quic_test_utils.h"
 #include "net/quic/test_tools/simple_quic_framer.h"
 #include "net/socket/socket_test_util.h"
@@ -42,74 +48,106 @@ namespace net {
 namespace test {
 namespace {
 
+const IPEndPoint kIpEndPoint(IPAddressNumber(kIPv4AddressSize, 0), 0);
 const char kServerHostname[] = "test.example.com";
 const uint16_t kServerPort = 443;
+const size_t kMaxReadersPerQuicSession = 5;
+
+class DefaultPacketWriterFactory : public QuicConnection::PacketWriterFactory {
+ public:
+  explicit DefaultPacketWriterFactory(DatagramClientSocket* socket)
+      : socket_(socket) {}
+  ~DefaultPacketWriterFactory() override {}
+
+  QuicPacketWriter* Create(QuicConnection* connection) const override {
+    scoped_ptr<net::QuicDefaultPacketWriter> writer(
+        new net::QuicDefaultPacketWriter(socket_));
+    writer->SetConnection(connection);
+    return writer.release();
+  }
+
+ private:
+  DatagramClientSocket* socket_;
+};
 
 class QuicChromiumClientSessionTest
     : public ::testing::TestWithParam<QuicVersion> {
  protected:
   QuicChromiumClientSessionTest()
       : crypto_config_(CryptoTestUtils::ProofVerifierForTesting()),
-        connection_(new PacketSavingConnection(&helper_,
-                                               Perspective::IS_CLIENT,
-                                               SupportedVersions(GetParam()))),
-        session_(
-            connection_,
-            GetSocket(),
-            /*stream_factory=*/nullptr,
-            QuicCryptoClientStreamFactory::GetDefaultFactory(),
-            &clock_,
-            &transport_security_state_,
-            make_scoped_ptr((QuicServerInfo*)nullptr),
-            QuicServerId(kServerHostname, kServerPort, PRIVACY_MODE_DISABLED),
-            kQuicYieldAfterPacketsRead,
-            QuicTime::Delta::FromMilliseconds(
-                kQuicYieldAfterDurationMilliseconds),
-            /*cert_verify_flags=*/0,
-            DefaultQuicConfig(),
-            &crypto_config_,
-            "CONNECTION_UNKNOWN",
-            base::TimeTicks::Now(),
-            base::ThreadTaskRunnerHandle::Get().get(),
-            /*socket_performance_watcher=*/nullptr,
-            &net_log_) {
-    session_.Initialize();
+        default_read_(new MockRead(SYNCHRONOUS, ERR_IO_PENDING, 0)),
+        socket_data_(
+            new SequencedSocketData(default_read_.get(), 1, nullptr, 0)),
+        random_(0),
+        helper_(base::ThreadTaskRunnerHandle::Get().get(), &clock_, &random_),
+        maker_(GetParam(), 0, &clock_, kServerHostname) {}
+
+  void Initialize() {
+    socket_factory_.AddSocketDataProvider(socket_data_.get());
+    scoped_ptr<DatagramClientSocket> socket =
+        socket_factory_.CreateDatagramClientSocket(DatagramSocket::DEFAULT_BIND,
+                                                   base::Bind(&base::RandInt),
+                                                   &net_log_, NetLog::Source());
+    socket->Connect(kIpEndPoint);
+    DefaultPacketWriterFactory writer_factory(socket.get());
+    QuicConnection* connection = new QuicConnection(
+        0, kIpEndPoint, &helper_, writer_factory, true, Perspective::IS_CLIENT,
+        SupportedVersions(GetParam()));
+    session_.reset(new QuicChromiumClientSession(
+        connection, std::move(socket),
+        /*stream_factory=*/nullptr, &crypto_client_stream_factory_, &clock_,
+        &transport_security_state_, make_scoped_ptr((QuicServerInfo*)nullptr),
+        QuicServerId(kServerHostname, kServerPort, PRIVACY_MODE_DISABLED),
+        kQuicYieldAfterPacketsRead,
+        QuicTime::Delta::FromMilliseconds(kQuicYieldAfterDurationMilliseconds),
+        /*cert_verify_flags=*/0, DefaultQuicConfig(), &crypto_config_,
+        "CONNECTION_UNKNOWN", base::TimeTicks::Now(),
+        base::ThreadTaskRunnerHandle::Get().get(),
+        /*socket_performance_watcher=*/nullptr, &net_log_));
+
+    scoped_refptr<X509Certificate> cert(
+        ImportCertFromFile(GetTestCertsDirectory(), "spdy_pooling.pem"));
+    verify_details_.cert_verify_result.verified_cert = cert;
+    verify_details_.cert_verify_result.is_issued_by_known_root = true;
     // Advance the time, because timers do not like uninitialized times.
-    connection_->AdvanceTime(QuicTime::Delta::FromSeconds(1));
+    clock_.AdvanceTime(QuicTime::Delta::FromSeconds(1));
+    session_->Initialize();
+    session_->StartReading();
   }
 
   void TearDown() override {
-    session_.CloseSessionOnError(ERR_ABORTED, QUIC_INTERNAL_ERROR);
+    session_->CloseSessionOnError(ERR_ABORTED, QUIC_INTERNAL_ERROR);
   }
 
-  scoped_ptr<DatagramClientSocket> GetSocket() {
-    socket_factory_.AddSocketDataProvider(&socket_data_);
-    return socket_factory_.CreateDatagramClientSocket(
-        DatagramSocket::DEFAULT_BIND, base::Bind(&base::RandInt), &net_log_,
-        NetLog::Source());
+  void CompleteCryptoHandshake() {
+    ASSERT_EQ(OK, session_->CryptoConnect(false, callback_.callback()));
   }
 
-  void CompleteCryptoHandshake() {
-    ASSERT_EQ(ERR_IO_PENDING,
-              session_.CryptoConnect(false, callback_.callback()));
-    CryptoTestUtils::FakeServerOptions server_options;
-    CryptoTestUtils::HandshakeWithFakeServer(
-        &helper_, connection_, session_.GetCryptoStream(), server_options);
-    ASSERT_EQ(OK, callback_.WaitForResult());
+  QuicPacketWriter* CreateQuicPacketWriter(DatagramClientSocket* socket,
+                                           QuicConnection* connection) const {
+    scoped_ptr<QuicDefaultPacketWriter> writer(
+        new QuicDefaultPacketWriter(socket));
+    writer->SetConnection(connection);
+    return writer.release();
   }
 
-  MockConnectionHelper helper_;
   QuicCryptoClientConfig crypto_config_;
-  PacketSavingConnection* connection_;
   TestNetLog net_log_;
+  BoundTestNetLog bound_net_log_;
   MockClientSocketFactory socket_factory_;
-  StaticSocketDataProvider socket_data_;
-  TransportSecurityState transport_security_state_;
-  QuicChromiumClientSession session_;
+  scoped_ptr<MockRead> default_read_;
+  scoped_ptr<SequencedSocketData> socket_data_;
   MockClock clock_;
   MockRandom random_;
+  QuicConnectionHelper helper_;
+  scoped_ptr<DefaultPacketWriterFactory> writer_factory_;
+  TransportSecurityState transport_security_state_;
+  MockCryptoClientStreamFactory crypto_client_stream_factory_;
+  scoped_ptr<QuicChromiumClientSession> session_;
   QuicConnectionVisitorInterface* visitor_;
   TestCompletionCallback callback_;
+  QuicTestPacketMaker maker_;
+  ProofVerifyDetailsChromium verify_details_;
 };
 
 INSTANTIATE_TEST_CASE_P(Tests,
@@ -117,43 +155,62 @@ INSTANTIATE_TEST_CASE_P(Tests,
                         ::testing::ValuesIn(QuicSupportedVersions()));
 
 TEST_P(QuicChromiumClientSessionTest, CryptoConnect) {
+  Initialize();
   CompleteCryptoHandshake();
 }
 
 TEST_P(QuicChromiumClientSessionTest, MaxNumStreams) {
+  MockRead reads[] = {MockRead(SYNCHRONOUS, ERR_IO_PENDING, 0)};
+  scoped_ptr<QuicEncryptedPacket> client_rst(maker_.MakeRstPacket(
+      1, true, kClientDataStreamId1, QUIC_RST_ACKNOWLEDGEMENT));
+  MockWrite writes[] = {
+      MockWrite(ASYNC, client_rst->data(), client_rst->length(), 1)};
+  socket_data_.reset(new SequencedSocketData(reads, arraysize(reads), writes,
+                                             arraysize(writes)));
+
+  Initialize();
   CompleteCryptoHandshake();
+  const size_t kMaxOpenStreams = session_->get_max_open_streams();
 
   std::vector<QuicReliableClientStream*> streams;
-  for (size_t i = 0; i < kDefaultMaxStreamsPerConnection; i++) {
+  for (size_t i = 0; i < kMaxOpenStreams; i++) {
     QuicReliableClientStream* stream =
-        session_.CreateOutgoingDynamicStream(kDefaultPriority);
+        session_->CreateOutgoingDynamicStream(kDefaultPriority);
     EXPECT_TRUE(stream);
     streams.push_back(stream);
   }
-  EXPECT_FALSE(session_.CreateOutgoingDynamicStream(kDefaultPriority));
+  EXPECT_FALSE(session_->CreateOutgoingDynamicStream(kDefaultPriority));
 
-  EXPECT_EQ(kDefaultMaxStreamsPerConnection,
-            session_.GetNumOpenOutgoingStreams());
+  EXPECT_EQ(kMaxOpenStreams, session_->GetNumOpenOutgoingStreams());
 
   // Close a stream and ensure I can now open a new one.
   QuicStreamId stream_id = streams[0]->id();
-  session_.CloseStream(stream_id);
+  session_->CloseStream(stream_id);
 
-  EXPECT_FALSE(session_.CreateOutgoingDynamicStream(kDefaultPriority));
+  EXPECT_FALSE(session_->CreateOutgoingDynamicStream(kDefaultPriority));
   QuicRstStreamFrame rst1(stream_id, QUIC_STREAM_NO_ERROR, 0);
-  session_.OnRstStream(rst1);
-  EXPECT_EQ(kDefaultMaxStreamsPerConnection - 1,
-            session_.GetNumOpenOutgoingStreams());
-  EXPECT_TRUE(session_.CreateOutgoingDynamicStream(kDefaultPriority));
+  session_->OnRstStream(rst1);
+  EXPECT_EQ(kMaxOpenStreams - 1, session_->GetNumOpenOutgoingStreams());
+  EXPECT_TRUE(session_->CreateOutgoingDynamicStream(kDefaultPriority));
 }
 
 TEST_P(QuicChromiumClientSessionTest, MaxNumStreamsViaRequest) {
+  MockRead reads[] = {MockRead(SYNCHRONOUS, ERR_IO_PENDING, 0)};
+  scoped_ptr<QuicEncryptedPacket> client_rst(maker_.MakeRstPacket(
+      1, true, kClientDataStreamId1, QUIC_RST_ACKNOWLEDGEMENT));
+  MockWrite writes[] = {
+      MockWrite(ASYNC, client_rst->data(), client_rst->length(), 1)};
+  socket_data_.reset(new SequencedSocketData(reads, arraysize(reads), writes,
+                                             arraysize(writes)));
+
+  Initialize();
   CompleteCryptoHandshake();
+  const size_t kMaxOpenStreams = session_->get_max_open_streams();
 
   std::vector<QuicReliableClientStream*> streams;
-  for (size_t i = 0; i < kDefaultMaxStreamsPerConnection; i++) {
+  for (size_t i = 0; i < kMaxOpenStreams; i++) {
     QuicReliableClientStream* stream =
-        session_.CreateOutgoingDynamicStream(kDefaultPriority);
+        session_->CreateOutgoingDynamicStream(kDefaultPriority);
     EXPECT_TRUE(stream);
     streams.push_back(stream);
   }
@@ -162,30 +219,32 @@ TEST_P(QuicChromiumClientSessionTest, MaxNumStreamsViaRequest) {
   QuicChromiumClientSession::StreamRequest stream_request;
   TestCompletionCallback callback;
   ASSERT_EQ(ERR_IO_PENDING,
-            stream_request.StartRequest(session_.GetWeakPtr(), &stream,
+            stream_request.StartRequest(session_->GetWeakPtr(), &stream,
                                         callback.callback()));
 
   // Close a stream and ensure I can now open a new one.
   QuicStreamId stream_id = streams[0]->id();
-  session_.CloseStream(stream_id);
+  session_->CloseStream(stream_id);
   QuicRstStreamFrame rst1(stream_id, QUIC_STREAM_NO_ERROR, 0);
-  session_.OnRstStream(rst1);
+  session_->OnRstStream(rst1);
   ASSERT_TRUE(callback.have_result());
   EXPECT_EQ(OK, callback.WaitForResult());
   EXPECT_TRUE(stream != nullptr);
 }
 
 TEST_P(QuicChromiumClientSessionTest, GoAwayReceived) {
+  Initialize();
   CompleteCryptoHandshake();
 
   // After receiving a GoAway, I should no longer be able to create outgoing
   // streams.
-  session_.connection()->OnGoAwayFrame(
+  session_->connection()->OnGoAwayFrame(
       QuicGoAwayFrame(QUIC_PEER_GOING_AWAY, 1u, "Going away."));
-  EXPECT_EQ(nullptr, session_.CreateOutgoingDynamicStream(kDefaultPriority));
+  EXPECT_EQ(nullptr, session_->CreateOutgoingDynamicStream(kDefaultPriority));
 }
 
 TEST_P(QuicChromiumClientSessionTest, CanPool) {
+  Initialize();
   // Load a cert that is valid for:
   //   www.example.org
   //   mail.example.org
@@ -197,16 +256,17 @@ TEST_P(QuicChromiumClientSessionTest, CanPool) {
   ASSERT_TRUE(details.cert_verify_result.verified_cert.get());
 
   CompleteCryptoHandshake();
-  session_.OnProofVerifyDetailsAvailable(details);
+  session_->OnProofVerifyDetailsAvailable(details);
 
-  EXPECT_TRUE(session_.CanPool("www.example.org", PRIVACY_MODE_DISABLED));
-  EXPECT_FALSE(session_.CanPool("www.example.org", PRIVACY_MODE_ENABLED));
-  EXPECT_TRUE(session_.CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
-  EXPECT_TRUE(session_.CanPool("mail.example.com", PRIVACY_MODE_DISABLED));
-  EXPECT_FALSE(session_.CanPool("mail.google.com", PRIVACY_MODE_DISABLED));
+  EXPECT_TRUE(session_->CanPool("www.example.org", PRIVACY_MODE_DISABLED));
+  EXPECT_FALSE(session_->CanPool("www.example.org", PRIVACY_MODE_ENABLED));
+  EXPECT_TRUE(session_->CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
+  EXPECT_TRUE(session_->CanPool("mail.example.com", PRIVACY_MODE_DISABLED));
+  EXPECT_FALSE(session_->CanPool("mail.google.com", PRIVACY_MODE_DISABLED));
 }
 
 TEST_P(QuicChromiumClientSessionTest, ConnectionPooledWithTlsChannelId) {
+  Initialize();
   // Load a cert that is valid for:
   //   www.example.org
   //   mail.example.org
@@ -218,17 +278,19 @@ TEST_P(QuicChromiumClientSessionTest, ConnectionPooledWithTlsChannelId) {
   ASSERT_TRUE(details.cert_verify_result.verified_cert.get());
 
   CompleteCryptoHandshake();
-  session_.OnProofVerifyDetailsAvailable(details);
-  QuicChromiumClientSessionPeer::SetHostname(&session_, "www.example.org");
-  QuicChromiumClientSessionPeer::SetChannelIDSent(&session_, true);
-
-  EXPECT_TRUE(session_.CanPool("www.example.org", PRIVACY_MODE_DISABLED));
-  EXPECT_TRUE(session_.CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
-  EXPECT_FALSE(session_.CanPool("mail.example.com", PRIVACY_MODE_DISABLED));
-  EXPECT_FALSE(session_.CanPool("mail.google.com", PRIVACY_MODE_DISABLED));
+  session_->OnProofVerifyDetailsAvailable(details);
+  QuicChromiumClientSessionPeer::SetHostname(session_.get(), "www.example.org");
+  QuicChromiumClientSessionPeer::SetChannelIDSent(session_.get(), true);
+
+  EXPECT_TRUE(session_->CanPool("www.example.org", PRIVACY_MODE_DISABLED));
+  EXPECT_TRUE(session_->CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
+  EXPECT_FALSE(session_->CanPool("mail.example.com", PRIVACY_MODE_DISABLED));
+  EXPECT_FALSE(session_->CanPool("mail.google.com", PRIVACY_MODE_DISABLED));
 }
 
 TEST_P(QuicChromiumClientSessionTest, ConnectionNotPooledWithDifferentPin) {
+  Initialize();
+
   uint8_t primary_pin = 1;
   uint8_t backup_pin = 2;
   uint8_t bad_pin = 3;
@@ -245,14 +307,16 @@ TEST_P(QuicChromiumClientSessionTest, ConnectionNotPooledWithDifferentPin) {
   ASSERT_TRUE(details.cert_verify_result.verified_cert.get());
 
   CompleteCryptoHandshake();
-  session_.OnProofVerifyDetailsAvailable(details);
-  QuicChromiumClientSessionPeer::SetHostname(&session_, "www.example.org");
-  QuicChromiumClientSessionPeer::SetChannelIDSent(&session_, true);
+  session_->OnProofVerifyDetailsAvailable(details);
+  QuicChromiumClientSessionPeer::SetHostname(session_.get(), "www.example.org");
+  QuicChromiumClientSessionPeer::SetChannelIDSent(session_.get(), true);
 
-  EXPECT_FALSE(session_.CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
+  EXPECT_FALSE(session_->CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
 }
 
 TEST_P(QuicChromiumClientSessionTest, ConnectionPooledWithMatchingPin) {
+  Initialize();
+
   uint8_t primary_pin = 1;
   uint8_t backup_pin = 2;
   AddPin(&transport_security_state_, "mail.example.org", primary_pin,
@@ -268,11 +332,208 @@ TEST_P(QuicChromiumClientSessionTest, ConnectionPooledWithMatchingPin) {
   ASSERT_TRUE(details.cert_verify_result.verified_cert.get());
 
   CompleteCryptoHandshake();
-  session_.OnProofVerifyDetailsAvailable(details);
-  QuicChromiumClientSessionPeer::SetHostname(&session_, "www.example.org");
-  QuicChromiumClientSessionPeer::SetChannelIDSent(&session_, true);
+  session_->OnProofVerifyDetailsAvailable(details);
+  QuicChromiumClientSessionPeer::SetHostname(session_.get(), "www.example.org");
+  QuicChromiumClientSessionPeer::SetChannelIDSent(session_.get(), true);
+
+  EXPECT_TRUE(session_->CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
+}
+
+TEST_P(QuicChromiumClientSessionTest, MigrateToSocket) {
+  Initialize();
+  CompleteCryptoHandshake();
+
+  char data[] = "ABCD";
+  scoped_ptr<QuicEncryptedPacket> ping(
+      maker_.MakePingPacket(1, /*include_version=*/false));
+  scoped_ptr<QuicEncryptedPacket> ack_and_data_out(maker_.MakeAckAndDataPacket(
+      2, false, 5, 1, 1, false, 0, StringPiece(data)));
+  MockRead reads[] = {MockRead(SYNCHRONOUS, ping->data(), ping->length(), 0),
+                      MockRead(SYNCHRONOUS, ERR_IO_PENDING, 1)};
+  MockWrite writes[] = {MockWrite(SYNCHRONOUS, ping->data(), ping->length(), 2),
+                        MockWrite(SYNCHRONOUS, ack_and_data_out->data(),
+                                  ack_and_data_out->length(), 3)};
+  StaticSocketDataProvider socket_data(reads, arraysize(reads), writes,
+                                       arraysize(writes));
+  socket_factory_.AddSocketDataProvider(&socket_data);
+
+  // Create connected socket.
+  scoped_ptr<DatagramClientSocket> new_socket =
+      socket_factory_.CreateDatagramClientSocket(DatagramSocket::DEFAULT_BIND,
+                                                 base::Bind(&base::RandInt),
+                                                 &net_log_, NetLog::Source());
+  EXPECT_EQ(OK, new_socket->Connect(kIpEndPoint));
+
+  // Create reader and writer.
+  scoped_ptr<QuicPacketReader> new_reader(new QuicPacketReader(
+      new_socket.get(), &clock_, session_.get(), kQuicYieldAfterPacketsRead,
+      QuicTime::Delta::FromMilliseconds(kQuicYieldAfterDurationMilliseconds),
+      bound_net_log_.bound()));
+  scoped_ptr<QuicPacketWriter> new_writer(
+      CreateQuicPacketWriter(new_socket.get(), session_->connection()));
+
+  // Migrate session.
+  EXPECT_TRUE(session_->MigrateToSocket(
+      std::move(new_socket), std::move(new_reader), std::move(new_writer)));
+
+  // Write data to session.
+  struct iovec iov[1];
+  iov[0].iov_base = data;
+  iov[0].iov_len = 4;
+  session_->WritevData(5, QuicIOVector(iov, arraysize(iov), 4), 0, false,
+                       MAY_FEC_PROTECT, nullptr);
+
+  EXPECT_TRUE(socket_data.AllReadDataConsumed());
+  EXPECT_TRUE(socket_data.AllWriteDataConsumed());
+}
+
+TEST_P(QuicChromiumClientSessionTest, MigrateToSocketMaxReaders) {
+  Initialize();
+  CompleteCryptoHandshake();
+
+  for (size_t i = 0; i < kMaxReadersPerQuicSession; ++i) {
+    MockRead reads[] = {MockRead(SYNCHRONOUS, ERR_IO_PENDING, 1)};
+    scoped_ptr<QuicEncryptedPacket> ping_out(
+        maker_.MakePingPacket(i + 1, /*include_version=*/true));
+    MockWrite writes[] = {
+        MockWrite(SYNCHRONOUS, ping_out->data(), ping_out->length(), i + 2)};
+    StaticSocketDataProvider socket_data(reads, arraysize(reads), writes,
+                                         arraysize(writes));
+    socket_factory_.AddSocketDataProvider(&socket_data);
+
+    // Create connected socket.
+    scoped_ptr<DatagramClientSocket> new_socket =
+        socket_factory_.CreateDatagramClientSocket(DatagramSocket::DEFAULT_BIND,
+                                                   base::Bind(&base::RandInt),
+                                                   &net_log_, NetLog::Source());
+    EXPECT_EQ(OK, new_socket->Connect(kIpEndPoint));
+
+    // Create reader and writer.
+    scoped_ptr<QuicPacketReader> new_reader(new QuicPacketReader(
+        new_socket.get(), &clock_, session_.get(), kQuicYieldAfterPacketsRead,
+        QuicTime::Delta::FromMilliseconds(kQuicYieldAfterDurationMilliseconds),
+        bound_net_log_.bound()));
+    scoped_ptr<QuicPacketWriter> new_writer(
+        CreateQuicPacketWriter(new_socket.get(), session_->connection()));
+
+    // Migrate session.
+    if (i < kMaxReadersPerQuicSession - 1) {
+      EXPECT_TRUE(session_->MigrateToSocket(
+          std::move(new_socket), std::move(new_reader), std::move(new_writer)));
+      EXPECT_TRUE(socket_data.AllReadDataConsumed());
+      EXPECT_TRUE(socket_data.AllWriteDataConsumed());
+    } else {
+      // Max readers exceeded.
+      EXPECT_FALSE(session_->MigrateToSocket(
+          std::move(new_socket), std::move(new_reader), std::move(new_writer)));
+
+      EXPECT_FALSE(socket_data.AllReadDataConsumed());
+      EXPECT_FALSE(socket_data.AllWriteDataConsumed());
+    }
+  }
+}
+
+TEST_P(QuicChromiumClientSessionTest, MigrateToSocketReadError) {
+  scoped_ptr<QuicEncryptedPacket> ping(
+      maker_.MakePingPacket(1, /*include_version=*/true));
+  MockRead old_reads[] = {
+      MockRead(SYNCHRONOUS, ping->data(), ping->length(), 0),
+      MockRead(ASYNC, ERR_IO_PENDING, 1),  // causes reading to pause.
+      MockRead(ASYNC, ERR_NETWORK_CHANGED, 2)};
+  socket_data_.reset(
+      new SequencedSocketData(old_reads, arraysize(old_reads), nullptr, 0));
+  Initialize();
+  CompleteCryptoHandshake();
+
+  MockWrite writes[] = {
+      MockWrite(SYNCHRONOUS, ping->data(), ping->length(), 1)};
+  MockRead new_reads[] = {
+      MockRead(SYNCHRONOUS, ping->data(), ping->length(), 0),
+      MockRead(ASYNC, ERR_IO_PENDING, 2),  // pause reading.
+      MockRead(ASYNC, ping->data(), ping->length(), 3),
+      MockRead(ASYNC, ERR_IO_PENDING, 4),  // pause reading
+      MockRead(ASYNC, ERR_NETWORK_CHANGED, 5)};
+  SequencedSocketData new_socket_data(new_reads, arraysize(new_reads), writes,
+                                      arraysize(writes));
+  socket_factory_.AddSocketDataProvider(&new_socket_data);
+
+  // Create connected socket.
+  scoped_ptr<DatagramClientSocket> new_socket =
+      socket_factory_.CreateDatagramClientSocket(DatagramSocket::DEFAULT_BIND,
+                                                 base::Bind(&base::RandInt),
+                                                 &net_log_, NetLog::Source());
+  EXPECT_EQ(OK, new_socket->Connect(kIpEndPoint));
+
+  // Create reader and writer.
+  scoped_ptr<QuicPacketReader> new_reader(new QuicPacketReader(
+      new_socket.get(), &clock_, session_.get(), kQuicYieldAfterPacketsRead,
+      QuicTime::Delta::FromMilliseconds(kQuicYieldAfterDurationMilliseconds),
+      bound_net_log_.bound()));
+  scoped_ptr<QuicPacketWriter> new_writer(
+      CreateQuicPacketWriter(new_socket.get(), session_->connection()));
+
+  // Store old socket and migrate session.
+  EXPECT_TRUE(session_->MigrateToSocket(
+      std::move(new_socket), std::move(new_reader), std::move(new_writer)));
+
+  // Read error on old socket does not impact session.
+  EXPECT_TRUE(socket_data_->IsPaused());
+  socket_data_->Resume();
+  EXPECT_TRUE(session_->connection()->connected());
+  EXPECT_TRUE(new_socket_data.IsPaused());
+  new_socket_data.Resume();
+
+  // Read error on new socket causes session close.
+  EXPECT_TRUE(new_socket_data.IsPaused());
+  EXPECT_TRUE(session_->connection()->connected());
+  new_socket_data.Resume();
+  EXPECT_FALSE(session_->connection()->connected());
+
+  EXPECT_TRUE(socket_data_->AllReadDataConsumed());
+  EXPECT_TRUE(socket_data_->AllWriteDataConsumed());
+  EXPECT_TRUE(new_socket_data.AllReadDataConsumed());
+  EXPECT_TRUE(new_socket_data.AllWriteDataConsumed());
+}
+
+TEST_P(QuicChromiumClientSessionTest, MigrateToSocketWriteError) {
+  Initialize();
+  CompleteCryptoHandshake();
 
-  EXPECT_TRUE(session_.CanPool("mail.example.org", PRIVACY_MODE_DISABLED));
+  scoped_ptr<QuicEncryptedPacket> ping(
+      maker_.MakePingPacket(1, /*include_version=*/true));
+  MockRead reads[] = {MockRead(SYNCHRONOUS, ERR_IO_PENDING, 0)};
+  MockWrite writes[] = {MockWrite(SYNCHRONOUS, ping->data(), ping->length(), 1),
+                        MockWrite(SYNCHRONOUS, ERR_FAILED, 2)};
+  SequencedSocketData socket_data(reads, arraysize(reads), writes,
+                                  arraysize(writes));
+  socket_factory_.AddSocketDataProvider(&socket_data);
+
+  // Create connected socket.
+  scoped_ptr<DatagramClientSocket> new_socket =
+      socket_factory_.CreateDatagramClientSocket(DatagramSocket::DEFAULT_BIND,
+                                                 base::Bind(&base::RandInt),
+                                                 &net_log_, NetLog::Source());
+  EXPECT_EQ(OK, new_socket->Connect(kIpEndPoint));
+
+  // Create reader and writer.
+  scoped_ptr<QuicPacketReader> new_reader(new QuicPacketReader(
+      new_socket.get(), &clock_, session_.get(), kQuicYieldAfterPacketsRead,
+      QuicTime::Delta::FromMilliseconds(kQuicYieldAfterDurationMilliseconds),
+      bound_net_log_.bound()));
+  scoped_ptr<QuicPacketWriter> new_writer(
+      CreateQuicPacketWriter(new_socket.get(), session_->connection()));
+
+  // Migrate session.
+  EXPECT_TRUE(session_->MigrateToSocket(
+      std::move(new_socket), std::move(new_reader), std::move(new_writer)));
+
+  // Write error on new socket causes session close.
+  EXPECT_TRUE(session_->connection()->connected());
+  session_->connection()->SendPing();
+  EXPECT_FALSE(session_->connection()->connected());
+
+  EXPECT_TRUE(socket_data.AllReadDataConsumed());
+  EXPECT_TRUE(socket_data.AllWriteDataConsumed());
 }
 
 }  // namespace