In-browser DNS-based service discovery system

chrome/browser/local_discovery/service_discovery_client_unittest.cc

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/memory/weak_ptr.h"
+#include "chrome/browser/local_discovery/service_discovery_client_impl.h"
+#include "net/base/net_errors.h"
+#include "net/dns/dns_protocol.h"
+#include "net/dns/mdns_client_impl.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using ::testing::_;
+using ::testing::Invoke;
+using ::testing::StrictMock;
+using ::testing::NiceMock;
+using ::testing::Mock;
+using ::testing::SaveArg;
+using ::testing::SetArgPointee;
+using ::testing::Return;
+using ::testing::Exactly;
+
+namespace local_discovery {
+
+namespace {
+
+const char kSamplePacketPTR[] = {
+  // Header
+  0x00, 0x00,               // ID is zeroed out
+  0x81, 0x80,               // Standard query response, RA, no error
+  0x00, 0x00,               // No questions (for simplicity)
+  0x00, 0x01,               // 1 RR (answers)
+  0x00, 0x00,               // 0 authority RRs
+  0x00, 0x00,               // 0 additional RRs
+
+  0x07, '_', 'p', 'r', 'i', 'v', 'e', 't',
+  0x04, '_', 't', 'c', 'p',
+  0x05, 'l', 'o', 'c', 'a', 'l',
+  0x00,
+  0x00, 0x0c,        // TYPE is PTR.
+  0x00, 0x01,        // CLASS is IN.
+  0x00, 0x00,        // TTL (4 bytes) is 1 second.
+  0x00, 0x01,
+  0x00, 0x08,        // RDLENGTH is 8 bytes.
+  0x05, 'h', 'e', 'l', 'l', 'o',
+  0xc0, 0x0c
+};
+
+const char kSamplePacketSRV[] = {
+  // Header
+  0x00, 0x00,               // ID is zeroed out
+  0x81, 0x80,               // Standard query response, RA, no error
+  0x00, 0x00,               // No questions (for simplicity)
+  0x00, 0x01,               // 1 RR (answers)
+  0x00, 0x00,               // 0 authority RRs
+  0x00, 0x00,               // 0 additional RRs
+
+  0x05, 'h', 'e', 'l', 'l', 'o',
+  0x07, '_', 'p', 'r', 'i', 'v', 'e', 't',
+  0x04, '_', 't', 'c', 'p',
+  0x05, 'l', 'o', 'c', 'a', 'l',
+  0x00,
+  0x00, 0x21,        // TYPE is SRV.
+  0x00, 0x01,        // CLASS is IN.
+  0x00, 0x00,        // TTL (4 bytes) is 1 second.
+  0x00, 0x01,
+  0x00, 0x15,        // RDLENGTH is 21 bytes.
+  0x00, 0x00,
+  0x00, 0x00,
+  0x22, 0xb8,  // port 8888
+  0x07, 'm', 'y', 'h', 'e', 'l', 'l', 'o',
+  0x05, 'l', 'o', 'c', 'a', 'l',
+  0x00,
+};
+
+const char kSamplePacketTXT[] = {
+  // Header
+  0x00, 0x00,               // ID is zeroed out
+  0x81, 0x80,               // Standard query response, RA, no error
+  0x00, 0x00,               // No questions (for simplicity)
+  0x00, 0x01,               // 1 RR (answers)
+  0x00, 0x00,               // 0 authority RRs
+  0x00, 0x00,               // 0 additional RRs
+
+  0x05, 'h', 'e', 'l', 'l', 'o',
+  0x07, '_', 'p', 'r', 'i', 'v', 'e', 't',
+  0x04, '_', 't', 'c', 'p',
+  0x05, 'l', 'o', 'c', 'a', 'l',
+  0x00,
+  0x00, 0x10,        // TYPE is PTR.
+  0x00, 0x01,        // CLASS is IN.
+  0x00, 0x00,        // TTL (4 bytes) is 20 hours, 47 minutes, 48 seconds.
+  0x00, 0x01,
+  0x00, 0x06,        // RDLENGTH is 21 bytes.
+  0x05, 'h', 'e', 'l', 'l', 'o'
+};
+
+const char kSamplePacketSRVA[] = {
+  // Header
+  0x00, 0x00,               // ID is zeroed out
+  0x81, 0x80,               // Standard query response, RA, no error
+  0x00, 0x00,               // No questions (for simplicity)
+  0x00, 0x02,               // 2 RR (answers)
+  0x00, 0x00,               // 0 authority RRs
+  0x00, 0x00,               // 0 additional RRs
+
+  0x05, 'h', 'e', 'l', 'l', 'o',
+  0x07, '_', 'p', 'r', 'i', 'v', 'e', 't',
+  0x04, '_', 't', 'c', 'p',
+  0x05, 'l', 'o', 'c', 'a', 'l',
+  0x00,
+  0x00, 0x21,        // TYPE is SRV.
+  0x00, 0x01,        // CLASS is IN.
+  0x00, 0x00,        // TTL (4 bytes) is 16 seconds.
+  0x00, 0x10,
+  0x00, 0x15,        // RDLENGTH is 21 bytes.
+  0x00, 0x00,
+  0x00, 0x00,
+  0x22, 0xb8,  // port 8888
+  0x07, 'm', 'y', 'h', 'e', 'l', 'l', 'o',
+  0x05, 'l', 'o', 'c', 'a', 'l',
+  0x00,
+
+  0x07, 'm', 'y', 'h', 'e', 'l', 'l', 'o',
+  0x05, 'l', 'o', 'c', 'a', 'l',
+  0x00,
+  0x00, 0x01,        // TYPE is A.
+  0x00, 0x01,        // CLASS is IN.
+  0x00, 0x00,        // TTL (4 bytes) is 16 seconds.
+  0x00, 0x10,
+  0x00, 0x04,        // RDLENGTH is 4 bytes.
+  0x01, 0x02,
+  0x03, 0x04,
+};
+
+
+class MockDatagramSocket : public net::DatagramServerSocket {
+ public:
+  int Listen(const net::IPEndPoint& address) {
+    return ListenInternal(address.ToString());
+  }
+
+  MOCK_METHOD1(ListenInternal, int(const std::string& address));
+
+  MOCK_METHOD4(RecvFrom, int(net::IOBuffer* buffer, int size,
+                             net::IPEndPoint* address,
+                             const net::CompletionCallback& callback));
+
+  int SendTo(net::IOBuffer* buf, int buf_len, const net::IPEndPoint& address,
+             const net::CompletionCallback& callback) {
+    return SendToInternal(std::string(buf->data(), buf_len), address.ToString(),
+                          callback);
+  }
+
+  MOCK_METHOD3(SendToInternal, int(const std::string& packet,
+                                   const std::string address,
+                                   const net::CompletionCallback& callback));
+
+  MOCK_METHOD1(SetReceiveBufferSize, bool(int32 size));
+  MOCK_METHOD1(SetSendBufferSize, bool(int32 size));
+
+  MOCK_METHOD0(Close, void());
+
+  MOCK_CONST_METHOD1(GetPeerAddress, int(net::IPEndPoint* address));
+  MOCK_CONST_METHOD1(GetLocalAddress, int(net::IPEndPoint* address));
+  MOCK_CONST_METHOD0(NetLog, const net::BoundNetLog&());
+
+  MOCK_METHOD0(AllowAddressReuse, void());
+  MOCK_METHOD0(AllowBroadcast, void());
+
+  int JoinGroup(const net::IPAddressNumber& group_address) const {
+    return JoinGroupInternal(net::IPAddressToString(group_address));
+  }
+
+  MOCK_CONST_METHOD1(JoinGroupInternal, int(const std::string& group));
+
+  int LeaveGroup(const net::IPAddressNumber& group_address) const {
+    return LeaveGroupInternal(net::IPAddressToString(group_address));
+  }
+
+  MOCK_CONST_METHOD1(LeaveGroupInternal, int(const std::string& group));
+
+  MOCK_METHOD1(SetMulticastTimeToLive, int(int ttl));
+
+  MOCK_METHOD1(SetMulticastLoopbackMode, int(bool loopback));
+};
+
+class MockDatagramSocketFactory
+    : public net::MDnsConnection::SocketFactory {
+ public:
+  MockDatagramSocketFactory() {
+  }
+
+  virtual ~MockDatagramSocketFactory() {
+  }
+
+  virtual scoped_ptr<net::DatagramServerSocket> CreateSocket() OVERRIDE {
+    scoped_ptr<MockDatagramSocket> new_socket(
+        new NiceMock<MockDatagramSocket>);
+
+    ON_CALL(*new_socket, SendToInternal(_, _, _))
+        .WillByDefault(Invoke(
+            this,
+            &MockDatagramSocketFactory::SendToInternal));
+
+    ON_CALL(*new_socket, RecvFrom(_, _, _, _))
+        .WillByDefault(Invoke(
+            this,
+            &MockDatagramSocketFactory::RecvFromInternal));
+
+    return new_socket.PassAs<net::DatagramServerSocket>();
+  }
+
+  int SendToInternal(const std::string& packet, const std::string& address,
+                     const net::CompletionCallback& callback) {
+    OnSendTo(packet);
+    return packet.size();
+  }
+
+  // The latest recieve callback is always saved, since the net::MDnsConnection
+  // does not care which socket a packet is received on.
+  int RecvFromInternal(net::IOBuffer* buffer, int size,
+                       net::IPEndPoint* address,
+                       const net::CompletionCallback& callback) {
+    recv_buffer_ = buffer;
+    recv_buffer_size_ = size;
+    recv_callback_ = callback;
+    return net::ERR_IO_PENDING;
+  }
+
+  void SimulateReceive(const char* packet, int size) {
+    DCHECK(recv_buffer_size_ >= size);
+    DCHECK(recv_buffer_.get());
+    DCHECK(!recv_callback_.is_null());
+
+    memcpy(recv_buffer_->data(), packet, size);
+    net::CompletionCallback recv_callback = recv_callback_;
+    recv_callback_.Reset();
+    recv_callback.Run(size);
+  }
+
+  MOCK_METHOD1(OnSendTo, void(const std::string&));
+
+ private:
+  scoped_refptr<net::IOBuffer> recv_buffer_;
+  int recv_buffer_size_;
+  net::CompletionCallback recv_callback_;
+};
+
+class MockServiceWatcherDelegate : public ServiceWatcher::Delegate {
+ public:
+  MockServiceWatcherDelegate() {}
+  virtual ~MockServiceWatcherDelegate() {}
+
+  MOCK_METHOD2(OnServiceUpdated, void(ServiceWatcher::UpdateType,
+                                      const std::string&));
+};
+
+class ServiceDiscoveryTest : public ::testing::Test {
+ public:
+  ServiceDiscoveryTest()
+      : socket_factory_(new MockDatagramSocketFactory),
+        mdns_client_(
+            scoped_ptr<net::MDnsConnection::SocketFactory>(
+                socket_factory_)) {
+    net::MDnsClient::SetInstance(&mdns_client_);
+  }
+
+  virtual ~ServiceDiscoveryTest() {
+    net::MDnsClient::SetInstance(NULL);
+  }
+
+ protected:
+  void RunFor(base::TimeDelta time_period) {
+    base::CancelableCallback<void()> callback(base::Bind(
+        &ServiceDiscoveryTest::Stop, base::Unretained(this)));
+    base::MessageLoop::current()->PostDelayedTask(
+        FROM_HERE, callback.callback(), time_period);
+
+    base::MessageLoop::current()->Run();
+    callback.Cancel();
+  }
+
+  void Stop() {
+    base::MessageLoop::current()->Quit();
+  }
+
+  MockDatagramSocketFactory* socket_factory_;
+  net::MDnsClientImpl mdns_client_;
+  ServiceDiscoveryClientImpl service_discovery_client_;
+  base::MessageLoop loop_;
+};
+
+TEST_F(ServiceDiscoveryTest, AddRemoveService) {
+  scoped_ptr<ServiceWatcher> watcher;
+  StrictMock<MockServiceWatcherDelegate> delegate;
+
+  watcher = service_discovery_client_.CreateServiceWatcher(
+      "_privet._tcp.local", &delegate);
+
+  watcher->Start();
+
+  EXPECT_CALL(delegate, OnServiceUpdated(ServiceWatcher::UPDATE_ADDED,
+                                         "hello._privet._tcp.local"))
+      .Times(Exactly(1));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketPTR, sizeof(kSamplePacketPTR));
+
+  EXPECT_CALL(delegate, OnServiceUpdated(ServiceWatcher::UPDATE_REMOVED,
+                                         "hello._privet._tcp.local"))
+      .Times(Exactly(1));
+
+  RunFor(base::TimeDelta::FromSeconds(2));
+};
+
+TEST_F(ServiceDiscoveryTest, DiscoverNewServices) {
+  scoped_ptr<ServiceWatcher> watcher;
+  StrictMock<MockServiceWatcherDelegate> delegate;
+
+  watcher = service_discovery_client_.CreateServiceWatcher(
+      "_privet._tcp.local", &delegate);
+
+  watcher->Start();
+
+  EXPECT_CALL(*socket_factory_, OnSendTo(_))
+      .Times(2);
+
+  watcher->DiscoverNewServices(false);
+};
+
+TEST_F(ServiceDiscoveryTest, GetAvailableServices) {
+  NiceMock<MockServiceWatcherDelegate> delegate;
+
+  std::vector<std::string> data_expected;
+  std::vector<std::string> data;
+
+  data_expected.push_back("hello._privet._tcp.local");
+
+  scoped_ptr<ServiceWatcher> watcher =
+      service_discovery_client_.CreateServiceWatcher(
+          "_privet._tcp.local", &delegate);
+
+  watcher->Start();
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketPTR, sizeof(kSamplePacketPTR));
+
+  watcher->GetAvailableServices(&data);
+
+  EXPECT_EQ(data, data_expected);
+};
+
+
+TEST_F(ServiceDiscoveryTest, ReadCachedServices) {
+  NiceMock<MockServiceWatcherDelegate> delegate_irrelevant;
+  scoped_ptr<ServiceWatcher> watcher_irrelevant =
+      service_discovery_client_.CreateServiceWatcher(
+          "_privet._tcp.local", &delegate_irrelevant);
+
+  watcher_irrelevant->Start();
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketPTR, sizeof(kSamplePacketPTR));
+
+  StrictMock<MockServiceWatcherDelegate> delegate;
+  scoped_ptr<ServiceWatcher> watcher =
+      service_discovery_client_.CreateServiceWatcher(
+          "_privet._tcp.local", &delegate);
+
+  watcher->Start();
+
+  EXPECT_CALL(delegate, OnServiceUpdated(ServiceWatcher::UPDATE_ADDED,
+                                         "hello._privet._tcp.local"))
+      .Times(Exactly(1));
+
+  watcher->ReadCachedServices();
+};
+
+TEST_F(ServiceDiscoveryTest, OnServiceChanged) {
+  StrictMock<MockServiceWatcherDelegate> delegate;
+  scoped_ptr<ServiceWatcher> watcher =
+      service_discovery_client_.CreateServiceWatcher(
+          "_privet._tcp.local", &delegate);
+
+  watcher->Start();
+
+  EXPECT_CALL(delegate, OnServiceUpdated(ServiceWatcher::UPDATE_ADDED,
+                                         "hello._privet._tcp.local"))
+      .Times(Exactly(1));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketPTR, sizeof(kSamplePacketPTR));
+
+  EXPECT_CALL(delegate, OnServiceUpdated(ServiceWatcher::UPDATE_CHANGED,
+                                         "hello._privet._tcp.local"))
+      .Times(Exactly(2));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketSRV, sizeof(kSamplePacketSRV));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketTXT, sizeof(kSamplePacketTXT));
+
+  watcher->ReadCachedServices();
+};
+
+
+class ServiceResolverTest : public ServiceDiscoveryTest {
+ public:
+  ServiceResolverTest() {
+    metadata_expected_.push_back("hello");
+    address_expected_ = net::HostPortPair("myhello.local", 8888);
+    ip_address_expected_.push_back(1);
+    ip_address_expected_.push_back(2);
+    ip_address_expected_.push_back(3);
+    ip_address_expected_.push_back(4);
+  }
+
+  ~ServiceResolverTest() {
+  }
+
+  void SetUp()  {
+    resolver_ = service_discovery_client_.CreateServiceResolver(
+        "hello._privet._tcp.local",
+        base::Bind(&ServiceResolverTest::OnFinishedResolving,
+                   base::Unretained(this)));
+  }
+
+  void OnFinishedResolving(ServiceResolver::RequestStatus request_status,
+                           const ServiceDescription& service_description) {
+    OnFinishedResolvingInternal(request_status);
+  }
+
+  MOCK_METHOD1(OnFinishedResolvingInternal, void(
+      ServiceResolver::RequestStatus));
+
+ protected:
+  scoped_ptr<ServiceResolver> resolver_;
+  net::IPAddressNumber ip_address_;
+  net::HostPortPair address_expected_;
+  std::vector<std::string> metadata_expected_;
+  net::IPAddressNumber ip_address_expected_;
+};
+
+TEST_F(ServiceResolverTest, TxtAndSrvButNoA) {
+  EXPECT_CALL(*socket_factory_, OnSendTo(_))
+      .Times(4);
+
+  EXPECT_FALSE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+  EXPECT_TRUE(resolver_->StartResolving());
+  EXPECT_TRUE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketSRV, sizeof(kSamplePacketSRV));
+
+  base::MessageLoop::current()->RunUntilIdle();
+
+  EXPECT_CALL(*this, OnFinishedResolvingInternal(
+      ServiceResolver::STATUS_SUCCESS));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketTXT, sizeof(kSamplePacketTXT));
+
+  EXPECT_EQ(address_expected_.ToString(),
+            resolver_->GetServiceDescription().address.ToString());
+  EXPECT_EQ(metadata_expected_, resolver_->GetServiceDescription().metadata);
+  EXPECT_EQ(net::IPAddressNumber(),
+            resolver_->GetServiceDescription().ip_address);
+};
+
+TEST_F(ServiceResolverTest, TxtSrvAndA) {
+  EXPECT_CALL(*socket_factory_, OnSendTo(_))
+      .Times(4);
+
+  EXPECT_FALSE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+  EXPECT_TRUE(resolver_->StartResolving());
+  EXPECT_TRUE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+
+  EXPECT_CALL(*this, OnFinishedResolvingInternal(
+      ServiceResolver::STATUS_SUCCESS));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketTXT, sizeof(kSamplePacketTXT));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketSRVA, sizeof(kSamplePacketSRVA));
+
+  EXPECT_EQ(address_expected_.ToString(),
+            resolver_->GetServiceDescription().address.ToString());
+  EXPECT_EQ(metadata_expected_, resolver_->GetServiceDescription().metadata);
+  EXPECT_EQ(ip_address_expected_,
+            resolver_->GetServiceDescription().ip_address);
+};
+
+TEST_F(ServiceResolverTest, JustSrv) {
+  EXPECT_CALL(*socket_factory_, OnSendTo(_))
+      .Times(4);
+
+  EXPECT_FALSE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+  EXPECT_TRUE(resolver_->StartResolving());
+  EXPECT_TRUE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+
+  EXPECT_CALL(*this, OnFinishedResolvingInternal(
+      ServiceResolver::STATUS_SUCCESS));
+
+  socket_factory_->SimulateReceive(
+      kSamplePacketSRVA, sizeof(kSamplePacketSRVA));
+
+  // TODO(noamsml): When NSEC record support is added, change this to use an
+  // NSEC record.
+  RunFor(base::TimeDelta::FromSeconds(4));
+
+  EXPECT_EQ(address_expected_.ToString(),
+            resolver_->GetServiceDescription().address.ToString());
+  EXPECT_EQ(std::vector<std::string>() ,
+            resolver_->GetServiceDescription().metadata);
+  EXPECT_EQ(ip_address_expected_,
+            resolver_->GetServiceDescription().ip_address);
+};
+
+TEST_F(ServiceResolverTest, WithNothing) {
+  EXPECT_CALL(*socket_factory_, OnSendTo(_))
+      .Times(4);
+
+  EXPECT_FALSE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+  EXPECT_TRUE(resolver_->StartResolving());
+  EXPECT_TRUE(resolver_->IsResolving());
+  EXPECT_FALSE(resolver_->HasResolved());
+
+  EXPECT_CALL(*this, OnFinishedResolvingInternal(
+      ServiceResolver::STATUS_REQUEST_TIMEOUT));
+
+  // TODO(noamsml): When NSEC record support is added, change this to use an
+  // NSEC record.
+  RunFor(base::TimeDelta::FromSeconds(4));
+};
+
+}  // namespace
+
+}  // namespace local_discovery