src/chrome/browser/local_discovery/service_discovery_client_mdns.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/local_discovery/service_discovery_client_mdns.h"
   6
   7 #include "base/memory/scoped_vector.h"
   8 #include "base/metrics/histogram.h"
   9 #include "chrome/common/local_discovery/service_discovery_client_impl.h"
  10 #include "content/public/browser/browser_thread.h"
  11 #include "net/dns/mdns_client.h"
  12 #include "net/udp/datagram_server_socket.h"
  13
  14 namespace local_discovery {
  15
  16 using content::BrowserThread;
  17
  18 // Base class for objects returned by ServiceDiscoveryClient implementation.
  19 // Handles interaction of client code on UI thread end net code on mdns thread.
  20 class ServiceDiscoveryClientMdns::Proxy {
  21  public:
  22   typedef base::WeakPtr<Proxy> WeakPtr;
  23
  24   explicit Proxy(ServiceDiscoveryClientMdns* client)
  25       : client_(client),
  26         weak_ptr_factory_(this) {
  27     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  28     client_->proxies_.AddObserver(this);
  29   }
  30
  31   virtual ~Proxy() {
  32     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  33     client_->proxies_.RemoveObserver(this);
  34   }
  35
  36   // Returns true if object is not yet shutdown.
  37   virtual bool IsValid() = 0;
  38
  39   // Notifies proxies that mDNS layer is going to be destroyed.
  40   virtual void OnMdnsDestroy() = 0;
  41
  42   // Notifies proxies that new mDNS instance is ready.
  43   virtual void OnNewMdnsReady() {
  44     DCHECK(!client_->need_dalay_mdns_tasks_);
  45     if (IsValid()) {
  46       for (size_t i = 0; i < delayed_tasks_.size(); ++i)
  47         client_->mdns_runner_->PostTask(FROM_HERE, delayed_tasks_[i]);
  48     }
  49     delayed_tasks_.clear();
  50   }
  51
  52   // Runs callback using this method to abort callback if instance of |Proxy|
  53   // is deleted.
  54   void RunCallback(const base::Closure& callback) {
  55     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  56     callback.Run();
  57   }
  58
  59  protected:
  60   void PostToMdnsThread(const base::Closure& task) {
  61     DCHECK(IsValid());
  62     // The first task on IO thread for each |mdns_| instance must be |InitMdns|.
  63     // |OnInterfaceListReady| could be delayed by |GetMDnsInterfacesToBind|
  64     // running on FILE thread, so |PostToMdnsThread| could be called to post
  65     // task for |mdns_| that is not initialized yet.
  66     if (!client_->need_dalay_mdns_tasks_) {
  67       client_->mdns_runner_->PostTask(FROM_HERE, task);
  68       return;
  69     }
  70     delayed_tasks_.push_back(task);
  71   }
  72
  73   static bool PostToUIThread(const base::Closure& task) {
  74     return BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, task);
  75   }
  76
  77   ServiceDiscoveryClient* client() {
  78     return client_->client_.get();
  79   }
  80
  81   WeakPtr GetWeakPtr() {
  82     return weak_ptr_factory_.GetWeakPtr();
  83   }
  84
  85   template<class T>
  86   void DeleteOnMdnsThread(T* t) {
  87     if (!t)
  88       return;
  89     if (!client_->mdns_runner_->DeleteSoon(FROM_HERE, t))
  90       delete t;
  91   }
  92
  93  private:
  94   scoped_refptr<ServiceDiscoveryClientMdns> client_;
  95   base::WeakPtrFactory<Proxy> weak_ptr_factory_;
  96   // Delayed |mdns_runner_| tasks.
  97   std::vector<base::Closure> delayed_tasks_;
  98   DISALLOW_COPY_AND_ASSIGN(Proxy);
  99 };
 100
 101 namespace {
 102
 103 const int kMaxRestartAttempts = 10;
 104 const int kRestartDelayOnNetworkChangeSeconds = 3;
 105
 106 typedef base::Callback<void(bool)> MdnsInitCallback;
 107
 108 class SocketFactory : public net::MDnsSocketFactory {
 109  public:
 110   explicit SocketFactory(const net::InterfaceIndexFamilyList& interfaces)
 111       : interfaces_(interfaces) {}
 112
 113   // net::MDnsSocketFactory implementation:
 114   void CreateSockets(
 115       ScopedVector<net::DatagramServerSocket>* sockets) override {
 116     for (size_t i = 0; i < interfaces_.size(); ++i) {
 117       DCHECK(interfaces_[i].second == net::ADDRESS_FAMILY_IPV4 ||
 118              interfaces_[i].second == net::ADDRESS_FAMILY_IPV6);
 119       scoped_ptr<net::DatagramServerSocket> socket(
 120           CreateAndBindMDnsSocket(interfaces_[i].second, interfaces_[i].first));
 121       if (socket)
 122         sockets->push_back(socket.release());
 123     }
 124   }
 125
 126  private:
 127   net::InterfaceIndexFamilyList interfaces_;
 128 };
 129
 130 void InitMdns(const MdnsInitCallback& on_initialized,
 131               const net::InterfaceIndexFamilyList& interfaces,
 132               net::MDnsClient* mdns) {
 133   SocketFactory socket_factory(interfaces);
 134   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
 135                           base::Bind(on_initialized,
 136                                      mdns->StartListening(&socket_factory)));
 137 }
 138
 139 template<class T>
 140 class ProxyBase : public ServiceDiscoveryClientMdns::Proxy, public T {
 141  public:
 142   typedef ProxyBase<T> Base;
 143
 144   explicit ProxyBase(ServiceDiscoveryClientMdns* client)
 145       : Proxy(client) {
 146   }
 147
 148   virtual ~ProxyBase() {
 149     DeleteOnMdnsThread(implementation_.release());
 150   }
 151
 152   virtual bool IsValid() override {
 153     return !!implementation();
 154   }
 155
 156   virtual void OnMdnsDestroy() override {
 157     DeleteOnMdnsThread(implementation_.release());
 158   };
 159
 160  protected:
 161   void set_implementation(scoped_ptr<T> implementation) {
 162     implementation_ = implementation.Pass();
 163   }
 164
 165   T* implementation()  const {
 166     return implementation_.get();
 167   }
 168
 169  private:
 170   scoped_ptr<T> implementation_;
 171   DISALLOW_COPY_AND_ASSIGN(ProxyBase);
 172 };
 173
 174 class ServiceWatcherProxy : public ProxyBase<ServiceWatcher> {
 175  public:
 176   ServiceWatcherProxy(ServiceDiscoveryClientMdns* client_mdns,
 177                       const std::string& service_type,
 178                       const ServiceWatcher::UpdatedCallback& callback)
 179       : ProxyBase(client_mdns),
 180         service_type_(service_type),
 181         callback_(callback) {
 182     // It's safe to call |CreateServiceWatcher| on UI thread, because
 183     // |MDnsClient| is not used there. It's simplify implementation.
 184     set_implementation(client()->CreateServiceWatcher(
 185         service_type,
 186         base::Bind(&ServiceWatcherProxy::OnCallback, GetWeakPtr(), callback)));
 187   }
 188
 189   // ServiceWatcher methods.
 190   void Start() override {
 191     if (implementation()) {
 192       PostToMdnsThread(base::Bind(&ServiceWatcher::Start,
 193                                   base::Unretained(implementation())));
 194     }
 195   }
 196
 197   void DiscoverNewServices(bool force_update) override {
 198     if (implementation()) {
 199       PostToMdnsThread(base::Bind(&ServiceWatcher::DiscoverNewServices,
 200                                   base::Unretained(implementation()),
 201                                   force_update));
 202     }
 203   }
 204
 205   void SetActivelyRefreshServices(bool actively_refresh_services) override {
 206     if (implementation()) {
 207       PostToMdnsThread(base::Bind(&ServiceWatcher::SetActivelyRefreshServices,
 208                                   base::Unretained(implementation()),
 209                                   actively_refresh_services));
 210     }
 211   }
 212
 213   std::string GetServiceType() const override { return service_type_; }
 214
 215   void OnNewMdnsReady() override {
 216     ProxyBase<ServiceWatcher>::OnNewMdnsReady();
 217     if (!implementation())
 218       callback_.Run(ServiceWatcher::UPDATE_INVALIDATED, "");
 219   }
 220
 221  private:
 222   static void OnCallback(const WeakPtr& proxy,
 223                          const ServiceWatcher::UpdatedCallback& callback,
 224                          UpdateType a1,
 225                          const std::string& a2) {
 226     DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
 227     PostToUIThread(base::Bind(&Base::RunCallback, proxy,
 228                               base::Bind(callback, a1, a2)));
 229   }
 230   std::string service_type_;
 231   ServiceWatcher::UpdatedCallback callback_;
 232   DISALLOW_COPY_AND_ASSIGN(ServiceWatcherProxy);
 233 };
 234
 235 class ServiceResolverProxy : public ProxyBase<ServiceResolver> {
 236  public:
 237   ServiceResolverProxy(ServiceDiscoveryClientMdns* client_mdns,
 238                        const std::string& service_name,
 239                        const ServiceResolver::ResolveCompleteCallback& callback)
 240       : ProxyBase(client_mdns),
 241         service_name_(service_name) {
 242     // It's safe to call |CreateServiceResolver| on UI thread, because
 243     // |MDnsClient| is not used there. It's simplify implementation.
 244     set_implementation(client()->CreateServiceResolver(
 245         service_name,
 246         base::Bind(&ServiceResolverProxy::OnCallback, GetWeakPtr(), callback)));
 247   }
 248
 249   // ServiceResolver methods.
 250   void StartResolving() override {
 251     if (implementation()) {
 252       PostToMdnsThread(base::Bind(&ServiceResolver::StartResolving,
 253                                   base::Unretained(implementation())));
 254     }
 255   };
 256
 257   std::string GetName() const override { return service_name_; }
 258
 259  private:
 260   static void OnCallback(
 261       const WeakPtr& proxy,
 262       const ServiceResolver::ResolveCompleteCallback& callback,
 263       RequestStatus a1,
 264       const ServiceDescription& a2) {
 265     DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
 266     PostToUIThread(base::Bind(&Base::RunCallback, proxy,
 267                               base::Bind(callback, a1, a2)));
 268   }
 269
 270   std::string service_name_;
 271   DISALLOW_COPY_AND_ASSIGN(ServiceResolverProxy);
 272 };
 273
 274 class LocalDomainResolverProxy : public ProxyBase<LocalDomainResolver> {
 275  public:
 276   LocalDomainResolverProxy(
 277       ServiceDiscoveryClientMdns* client_mdns,
 278       const std::string& domain,
 279       net::AddressFamily address_family,
 280       const LocalDomainResolver::IPAddressCallback& callback)
 281       : ProxyBase(client_mdns) {
 282     // It's safe to call |CreateLocalDomainResolver| on UI thread, because
 283     // |MDnsClient| is not used there. It's simplify implementation.
 284     set_implementation(client()->CreateLocalDomainResolver(
 285         domain,
 286         address_family,
 287         base::Bind(
 288             &LocalDomainResolverProxy::OnCallback, GetWeakPtr(), callback)));
 289   }
 290
 291   // LocalDomainResolver methods.
 292   void Start() override {
 293     if (implementation()) {
 294       PostToMdnsThread(base::Bind(&LocalDomainResolver::Start,
 295                                   base::Unretained(implementation())));
 296     }
 297   };
 298
 299  private:
 300   static void OnCallback(const WeakPtr& proxy,
 301                          const LocalDomainResolver::IPAddressCallback& callback,
 302                          bool a1,
 303                          const net::IPAddressNumber& a2,
 304                          const net::IPAddressNumber& a3) {
 305     DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
 306     PostToUIThread(base::Bind(&Base::RunCallback, proxy,
 307                               base::Bind(callback, a1, a2, a3)));
 308   }
 309
 310   DISALLOW_COPY_AND_ASSIGN(LocalDomainResolverProxy);
 311 };
 312
 313 }  // namespace
 314
 315 ServiceDiscoveryClientMdns::ServiceDiscoveryClientMdns()
 316     : mdns_runner_(
 317           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO)),
 318       restart_attempts_(0),
 319       need_dalay_mdns_tasks_(true),
 320       weak_ptr_factory_(this) {
 321   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 322   net::NetworkChangeNotifier::AddNetworkChangeObserver(this);
 323   StartNewClient();
 324 }
 325
 326 scoped_ptr<ServiceWatcher> ServiceDiscoveryClientMdns::CreateServiceWatcher(
 327     const std::string& service_type,
 328     const ServiceWatcher::UpdatedCallback& callback) {
 329   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 330   return scoped_ptr<ServiceWatcher>(
 331       new ServiceWatcherProxy(this, service_type, callback));
 332 }
 333
 334 scoped_ptr<ServiceResolver> ServiceDiscoveryClientMdns::CreateServiceResolver(
 335     const std::string& service_name,
 336     const ServiceResolver::ResolveCompleteCallback& callback) {
 337   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 338   return scoped_ptr<ServiceResolver>(
 339       new ServiceResolverProxy(this, service_name, callback));
 340 }
 341
 342 scoped_ptr<LocalDomainResolver>
 343 ServiceDiscoveryClientMdns::CreateLocalDomainResolver(
 344     const std::string& domain,
 345     net::AddressFamily address_family,
 346     const LocalDomainResolver::IPAddressCallback& callback) {
 347   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 348   return scoped_ptr<LocalDomainResolver>(
 349       new LocalDomainResolverProxy(this, domain, address_family, callback));
 350 }
 351
 352 ServiceDiscoveryClientMdns::~ServiceDiscoveryClientMdns() {
 353   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 354   net::NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
 355   DestroyMdns();
 356 }
 357
 358 void ServiceDiscoveryClientMdns::OnNetworkChanged(
 359     net::NetworkChangeNotifier::ConnectionType type) {
 360   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 361   // Only network changes resets counter.
 362   restart_attempts_ = 0;
 363   ScheduleStartNewClient();
 364 }
 365
 366 void ServiceDiscoveryClientMdns::ScheduleStartNewClient() {
 367   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 368   OnBeforeMdnsDestroy();
 369   if (restart_attempts_ < kMaxRestartAttempts) {
 370     base::MessageLoop::current()->PostDelayedTask(
 371         FROM_HERE,
 372         base::Bind(&ServiceDiscoveryClientMdns::StartNewClient,
 373                    weak_ptr_factory_.GetWeakPtr()),
 374         base::TimeDelta::FromSeconds(
 375             kRestartDelayOnNetworkChangeSeconds * (1 << restart_attempts_)));
 376   } else {
 377     ReportSuccess();
 378   }
 379 }
 380
 381 void ServiceDiscoveryClientMdns::StartNewClient() {
 382   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 383   ++restart_attempts_;
 384   DestroyMdns();
 385   mdns_.reset(net::MDnsClient::CreateDefault().release());
 386   client_.reset(new ServiceDiscoveryClientImpl(mdns_.get()));
 387   BrowserThread::PostTaskAndReplyWithResult(
 388       BrowserThread::FILE,
 389       FROM_HERE,
 390       base::Bind(&net::GetMDnsInterfacesToBind),
 391       base::Bind(&ServiceDiscoveryClientMdns::OnInterfaceListReady,
 392                  weak_ptr_factory_.GetWeakPtr()));
 393 }
 394
 395 void ServiceDiscoveryClientMdns::OnInterfaceListReady(
 396     const net::InterfaceIndexFamilyList& interfaces) {
 397   mdns_runner_->PostTask(
 398       FROM_HERE,
 399       base::Bind(&InitMdns,
 400                  base::Bind(&ServiceDiscoveryClientMdns::OnMdnsInitialized,
 401                             weak_ptr_factory_.GetWeakPtr()),
 402                  interfaces,
 403                  base::Unretained(mdns_.get())));
 404 }
 405
 406 void ServiceDiscoveryClientMdns::OnMdnsInitialized(bool success) {
 407   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 408   if (!success) {
 409     ScheduleStartNewClient();
 410     return;
 411   }
 412   ReportSuccess();
 413
 414   // Initialization is done, no need to delay tasks.
 415   need_dalay_mdns_tasks_ = false;
 416   FOR_EACH_OBSERVER(Proxy, proxies_, OnNewMdnsReady());
 417 }
 418
 419 void ServiceDiscoveryClientMdns::ReportSuccess() {
 420   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 421   UMA_HISTOGRAM_COUNTS_100("LocalDiscovery.ClientRestartAttempts",
 422                            restart_attempts_);
 423 }
 424
 425 void ServiceDiscoveryClientMdns::OnBeforeMdnsDestroy() {
 426   need_dalay_mdns_tasks_ = true;
 427   weak_ptr_factory_.InvalidateWeakPtrs();
 428   FOR_EACH_OBSERVER(Proxy, proxies_, OnMdnsDestroy());
 429 }
 430
 431 void ServiceDiscoveryClientMdns::DestroyMdns() {
 432   OnBeforeMdnsDestroy();
 433   // After calling |Proxy::OnMdnsDestroy| all references to client_ and mdns_
 434   // should be destroyed.
 435   if (client_)
 436     mdns_runner_->DeleteSoon(FROM_HERE, client_.release());
 437   if (mdns_)
 438     mdns_runner_->DeleteSoon(FROM_HERE, mdns_.release());
 439 }
 440
 441 }  // namespace local_discovery