TransportController refactoring

webrtc/p2p/base/faketransportcontroller.h

+/*
+ *  Copyright 2009 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_P2P_BASE_FAKETRANSPORTCONTROLLER_H_
+#define WEBRTC_P2P_BASE_FAKETRANSPORTCONTROLLER_H_
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "webrtc/p2p/base/transport.h"
+#include "webrtc/p2p/base/transportchannel.h"
+#include "webrtc/p2p/base/transportcontroller.h"
+#include "webrtc/p2p/base/transportchannelimpl.h"
+#include "webrtc/base/bind.h"
+#include "webrtc/base/buffer.h"
+#include "webrtc/base/fakesslidentity.h"
+#include "webrtc/base/messagequeue.h"
+#include "webrtc/base/sigslot.h"
+#include "webrtc/base/sslfingerprint.h"
+#include "webrtc/base/thread.h"
+
+namespace cricket {
+
+class FakeTransport;
+
+struct PacketMessageData : public rtc::MessageData {
+  PacketMessageData(const char* data, size_t len) : packet(data, len) {}
+  rtc::Buffer packet;
+};
+
+// Fake transport channel class, which can be passed to anything that needs a
+// transport channel. Can be informed of another FakeTransportChannel via
+// SetDestination.
+// TODO(hbos): Move implementation to .cc file, this and other classes in file.
+class FakeTransportChannel : public TransportChannelImpl,
+                             public rtc::MessageHandler {
+ public:
+  explicit FakeTransportChannel(Transport* transport,
+                                const std::string& name,
+                                int component)
+      : TransportChannelImpl(name, component),
+        transport_(transport),
+        dtls_fingerprint_("", nullptr, 0) {}
+  ~FakeTransportChannel() { Reset(); }
+
+  uint64 IceTiebreaker() const { return tiebreaker_; }
+  IceMode remote_ice_mode() const { return remote_ice_mode_; }
+  const std::string& ice_ufrag() const { return ice_ufrag_; }
+  const std::string& ice_pwd() const { return ice_pwd_; }
+  const std::string& remote_ice_ufrag() const { return remote_ice_ufrag_; }
+  const std::string& remote_ice_pwd() const { return remote_ice_pwd_; }
+  const rtc::SSLFingerprint& dtls_fingerprint() const {
+    return dtls_fingerprint_;
+  }
+
+  // If async, will send packets by "Post"-ing to message queue instead of
+  // synchronously "Send"-ing.
+  void SetAsync(bool async) { async_ = async; }
+
+  Transport* GetTransport() override { return transport_; }
+
+  TransportChannelState GetState() const override {
+    if (connection_count_ == 0) {
+      return had_connection_ ? TransportChannelState::STATE_FAILED
+                             : TransportChannelState::STATE_INIT;
+    }
+
+    if (connection_count_ == 1) {
+      return TransportChannelState::STATE_COMPLETED;
+    }
+
+    return TransportChannelState::STATE_CONNECTING;
+  }
+
+  void SetIceRole(IceRole role) override { role_ = role; }
+  IceRole GetIceRole() const override { return role_; }
+  void SetIceTiebreaker(uint64 tiebreaker) override {
+    tiebreaker_ = tiebreaker;
+  }
+  void SetIceCredentials(const std::string& ice_ufrag,
+                         const std::string& ice_pwd) override {
+    ice_ufrag_ = ice_ufrag;
+    ice_pwd_ = ice_pwd;
+  }
+  void SetRemoteIceCredentials(const std::string& ice_ufrag,
+                               const std::string& ice_pwd) override {
+    remote_ice_ufrag_ = ice_ufrag;
+    remote_ice_pwd_ = ice_pwd;
+  }
+
+  void SetRemoteIceMode(IceMode mode) override { remote_ice_mode_ = mode; }
+  bool SetRemoteFingerprint(const std::string& alg,
+                            const uint8* digest,
+                            size_t digest_len) override {
+    dtls_fingerprint_ = rtc::SSLFingerprint(alg, digest, digest_len);
+    return true;
+  }
+  bool SetSslRole(rtc::SSLRole role) override {
+    ssl_role_ = role;
+    return true;
+  }
+  bool GetSslRole(rtc::SSLRole* role) const override {
+    *role = ssl_role_;
+    return true;
+  }
+
+  void Connect() override {
+    if (state_ == STATE_INIT) {
+      state_ = STATE_CONNECTING;
+      // Connect is expected to start candidate gathering
+      if (gathering_state_ != kIceGatheringGathering) {
+        gathering_state_ = kIceGatheringGathering;
+        SignalGatheringState(this);
+      }
+    }
+  }
+
+  IceGatheringState gathering_state() const override {
+    return gathering_state_;
+  }
+
+  void Reset() {
+    if (state_ != STATE_INIT) {
+      state_ = STATE_INIT;
+      if (dest_) {
+        dest_->state_ = STATE_INIT;
+        dest_->dest_ = nullptr;
+        dest_ = nullptr;
+      }
+    }
+  }
+
+  void SetWritable(bool writable) { set_writable(writable); }
+
+  void SetDestination(FakeTransportChannel* dest) {
+    if (state_ == STATE_CONNECTING && dest) {
+      // This simulates the delivery of candidates.
+      dest_ = dest;
+      dest_->dest_ = this;
+      if (identity_ && dest_->identity_) {
+        do_dtls_ = true;
+        dest_->do_dtls_ = true;
+        NegotiateSrtpCiphers();
+      }
+      state_ = STATE_CONNECTED;
+      dest_->state_ = STATE_CONNECTED;
+      set_writable(true);
+      dest_->set_writable(true);
+    } else if (state_ == STATE_CONNECTED && !dest) {
+      // Simulates loss of connectivity, by asymmetrically forgetting dest_.
+      dest_ = nullptr;
+      state_ = STATE_CONNECTING;
+      set_writable(false);
+    }
+  }
+
+  void SetConnectionCount(size_t connection_count) {
+    size_t old_connection_count = connection_count_;
+    connection_count_ = connection_count;
+    if (connection_count)
+      had_connection_ = true;
+    if (connection_count_ < old_connection_count)
+      SignalConnectionRemoved(this);
+  }
+
+  void SetCandidatesGatheringComplete() {
+    if (gathering_state_ != kIceGatheringComplete) {
+      gathering_state_ = kIceGatheringComplete;
+      SignalGatheringState(this);
+    }
+  }
+
+  void SetReceiving(bool receiving) { set_receiving(receiving); }
+
+  void SetReceivingTimeout(int timeout) override {
+    receiving_timeout_ = timeout;
+  }
+
+  int receiving_timeout() const { return receiving_timeout_; }
+
+  int SendPacket(const char* data,
+                 size_t len,
+                 const rtc::PacketOptions& options,
+                 int flags) override {
+    if (state_ != STATE_CONNECTED) {
+      return -1;
+    }
+
+    if (flags != PF_SRTP_BYPASS && flags != 0) {
+      return -1;
+    }
+
+    PacketMessageData* packet = new PacketMessageData(data, len);
+    if (async_) {
+      rtc::Thread::Current()->Post(this, 0, packet);
+    } else {
+      rtc::Thread::Current()->Send(this, 0, packet);
+    }
+    return static_cast<int>(len);
+  }
+  int SetOption(rtc::Socket::Option opt, int value) override { return true; }
+  bool GetOption(rtc::Socket::Option opt, int* value) override { return true; }
+  int GetError() override { return 0; }
+
+  void AddRemoteCandidate(const Candidate& candidate) override {
+    remote_candidates_.push_back(candidate);
+  }
+  const Candidates& remote_candidates() const { return remote_candidates_; }
+
+  void OnMessage(rtc::Message* msg) override {
+    PacketMessageData* data = static_cast<PacketMessageData*>(msg->pdata);
+    dest_->SignalReadPacket(dest_, data->packet.data<char>(),
+                            data->packet.size(), rtc::CreatePacketTime(0), 0);
+    delete data;
+  }
+
+  bool SetLocalIdentity(rtc::SSLIdentity* identity) {
+    identity_ = identity;
+    return true;
+  }
+
+  void SetRemoteCertificate(rtc::FakeSSLCertificate* cert) {
+    remote_cert_ = cert;
+  }
+
+  bool IsDtlsActive() const override { return do_dtls_; }
+
+  bool SetSrtpCiphers(const std::vector<std::string>& ciphers) override {
+    srtp_ciphers_ = ciphers;
+    return true;
+  }
+
+  bool GetSrtpCipher(std::string* cipher) override {
+    if (!chosen_srtp_cipher_.empty()) {
+      *cipher = chosen_srtp_cipher_;
+      return true;
+    }
+    return false;
+  }
+
+  bool GetSslCipher(std::string* cipher) override { return false; }
+
+  bool GetLocalIdentity(rtc::SSLIdentity** identity) const override {
+    if (!identity_)
+      return false;
+
+    *identity = identity_->GetReference();
+    return true;
+  }
+
+  bool GetRemoteCertificate(rtc::SSLCertificate** cert) const override {
+    if (!remote_cert_)
+      return false;
+
+    *cert = remote_cert_->GetReference();
+    return true;
+  }
+
+  bool ExportKeyingMaterial(const std::string& label,
+                            const uint8* context,
+                            size_t context_len,
+                            bool use_context,
+                            uint8* result,
+                            size_t result_len) override {
+    if (!chosen_srtp_cipher_.empty()) {
+      memset(result, 0xff, result_len);
+      return true;
+    }
+
+    return false;
+  }
+
+  void NegotiateSrtpCiphers() {
+    for (std::vector<std::string>::const_iterator it1 = srtp_ciphers_.begin();
+         it1 != srtp_ciphers_.end(); ++it1) {
+      for (std::vector<std::string>::const_iterator it2 =
+               dest_->srtp_ciphers_.begin();
+           it2 != dest_->srtp_ciphers_.end(); ++it2) {
+        if (*it1 == *it2) {
+          chosen_srtp_cipher_ = *it1;
+          dest_->chosen_srtp_cipher_ = *it2;
+          return;
+        }
+      }
+    }
+  }
+
+  bool GetStats(ConnectionInfos* infos) override {
+    ConnectionInfo info;
+    infos->clear();
+    infos->push_back(info);
+    return true;
+  }
+
+  void set_ssl_max_protocol_version(rtc::SSLProtocolVersion version) {
+    ssl_max_version_ = version;
+  }
+  rtc::SSLProtocolVersion ssl_max_protocol_version() const {
+    return ssl_max_version_;
+  }
+
+ private:
+  enum State { STATE_INIT, STATE_CONNECTING, STATE_CONNECTED };
+  Transport* transport_;
+  FakeTransportChannel* dest_ = nullptr;
+  State state_ = STATE_INIT;
+  bool async_ = false;
+  Candidates remote_candidates_;
+  rtc::SSLIdentity* identity_ = nullptr;
+  rtc::FakeSSLCertificate* remote_cert_ = nullptr;
+  bool do_dtls_ = false;
+  std::vector<std::string> srtp_ciphers_;
+  std::string chosen_srtp_cipher_;
+  int receiving_timeout_ = -1;
+  IceRole role_ = ICEROLE_UNKNOWN;
+  uint64 tiebreaker_ = 0;
+  std::string ice_ufrag_;
+  std::string ice_pwd_;
+  std::string remote_ice_ufrag_;
+  std::string remote_ice_pwd_;
+  IceMode remote_ice_mode_ = ICEMODE_FULL;
+  rtc::SSLProtocolVersion ssl_max_version_ = rtc::SSL_PROTOCOL_DTLS_10;
+  rtc::SSLFingerprint dtls_fingerprint_;
+  rtc::SSLRole ssl_role_ = rtc::SSL_CLIENT;
+  size_t connection_count_ = 0;
+  IceGatheringState gathering_state_ = kIceGatheringNew;
+  bool had_connection_ = false;
+};
+
+// Fake transport class, which can be passed to anything that needs a Transport.
+// Can be informed of another FakeTransport via SetDestination (low-tech way
+// of doing candidates)
+class FakeTransport : public Transport {
+ public:
+  typedef std::map<int, FakeTransportChannel*> ChannelMap;
+
+  explicit FakeTransport(const std::string& name) : Transport(name, nullptr) {}
+
+  // Note that we only have a constructor with the allocator parameter so it can
+  // be wrapped by a DtlsTransport.
+  FakeTransport(const std::string& name, PortAllocator* allocator)
+      : Transport(name, nullptr) {}
+
+  ~FakeTransport() { DestroyAllChannels(); }
+
+  const ChannelMap& channels() const { return channels_; }
+
+  // If async, will send packets by "Post"-ing to message queue instead of
+  // synchronously "Send"-ing.
+  void SetAsync(bool async) { async_ = async; }
+  void SetDestination(FakeTransport* dest) {
+    dest_ = dest;
+    for (const auto& kv : channels_) {
+      // TODO(hbos): SetLocalCertificate
+      kv.second->SetLocalIdentity(certificate_ ? certificate_->identity()
+                                               : nullptr);
+      SetChannelDestination(kv.first, kv.second);
+    }
+  }
+
+  void SetWritable(bool writable) {
+    for (const auto& kv : channels_) {
+      kv.second->SetWritable(writable);
+    }
+  }
+
+  void SetLocalCertificate(
+      const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) override {
+    certificate_ = certificate;
+  }
+  bool GetLocalCertificate(
+      rtc::scoped_refptr<rtc::RTCCertificate>* certificate) override {
+    if (!certificate_)
+      return false;
+
+    *certificate = certificate_;
+    return true;
+  }
+
+  bool GetSslRole(rtc::SSLRole* role) const override {
+    if (channels_.empty()) {
+      return false;
+    }
+    return channels_.cbegin()->second->GetSslRole(role);
+  }
+
+  bool SetSslMaxProtocolVersion(rtc::SSLProtocolVersion version) override {
+    ssl_max_version_ = version;
+    for (const auto& kv : channels_) {
+      kv.second->set_ssl_max_protocol_version(ssl_max_version_);
+    }
+    return true;
+  }
+  rtc::SSLProtocolVersion ssl_max_protocol_version() const {
+    return ssl_max_version_;
+  }
+
+  using Transport::local_description;
+  using Transport::remote_description;
+
+ protected:
+  TransportChannelImpl* CreateTransportChannel(int component) override {
+    if (channels_.find(component) != channels_.end()) {
+      return nullptr;
+    }
+    FakeTransportChannel* channel =
+        new FakeTransportChannel(this, name(), component);
+    channel->set_ssl_max_protocol_version(ssl_max_version_);
+    channel->SetAsync(async_);
+    SetChannelDestination(component, channel);
+    channels_[component] = channel;
+    return channel;
+  }
+
+  void DestroyTransportChannel(TransportChannelImpl* channel) override {
+    channels_.erase(channel->component());
+    delete channel;
+  }
+
+ private:
+  FakeTransportChannel* GetFakeChannel(int component) {
+    auto it = channels_.find(component);
+    return (it != channels_.end()) ? it->second : nullptr;
+  }
+
+  void SetChannelDestination(int component, FakeTransportChannel* channel) {
+    FakeTransportChannel* dest_channel = nullptr;
+    if (dest_) {
+      dest_channel = dest_->GetFakeChannel(component);
+      if (dest_channel) {
+        // TODO(hbos): SetLocalCertificate
+        dest_channel->SetLocalIdentity(
+            dest_->certificate_ ? dest_->certificate_->identity() : nullptr);
+      }
+    }
+    channel->SetDestination(dest_channel);
+  }
+
+  // Note, this is distinct from the Channel map owned by Transport.
+  // This map just tracks the FakeTransportChannels created by this class.
+  // It's mainly needed so that we can access a FakeTransportChannel directly,
+  // even if wrapped by a DtlsTransportChannelWrapper.
+  ChannelMap channels_;
+  FakeTransport* dest_ = nullptr;
+  bool async_ = false;
+  rtc::scoped_refptr<rtc::RTCCertificate> certificate_;
+  rtc::SSLProtocolVersion ssl_max_version_ = rtc::SSL_PROTOCOL_DTLS_10;
+};
+
+// Fake TransportController class, which can be passed into a BaseChannel object
+// for test purposes. Can be connected to other FakeTransportControllers via
+// Connect().
+//
+// This fake is unusual in that for the most part, it's implemented with the
+// real TransportController code, but with fake TransportChannels underneath.
+class FakeTransportController : public TransportController {
+ public:
+  FakeTransportController()
+      : TransportController(rtc::Thread::Current(),
+                            rtc::Thread::Current(),
+                            nullptr),
+        fail_create_channel_(false) {}
+
+  explicit FakeTransportController(IceRole role)
+      : TransportController(rtc::Thread::Current(),
+                            rtc::Thread::Current(),
+                            nullptr),
+        fail_create_channel_(false) {
+    SetIceRole(role);
+  }
+
+  explicit FakeTransportController(rtc::Thread* worker_thread)
+      : TransportController(rtc::Thread::Current(), worker_thread, nullptr),
+        fail_create_channel_(false) {}
+
+  FakeTransportController(rtc::Thread* worker_thread, IceRole role)
+      : TransportController(rtc::Thread::Current(), worker_thread, nullptr),
+        fail_create_channel_(false) {
+    SetIceRole(role);
+  }
+
+  FakeTransport* GetTransport_w(const std::string& transport_name) {
+    return static_cast<FakeTransport*>(
+        TransportController::GetTransport_w(transport_name));
+  }
+
+  void Connect(FakeTransportController* dest) {
+    worker_thread()->Invoke<void>(
+        rtc::Bind(&FakeTransportController::Connect_w, this, dest));
+  }
+
+  TransportChannel* CreateTransportChannel_w(const std::string& transport_name,
+                                             int component) override {
+    if (fail_create_channel_) {
+      return nullptr;
+    }
+    return TransportController::CreateTransportChannel_w(transport_name,
+                                                         component);
+  }
+
+  void set_fail_channel_creation(bool fail_channel_creation) {
+    fail_create_channel_ = fail_channel_creation;
+  }
+
+ protected:
+  Transport* CreateTransport_w(const std::string& transport_name) override {
+    return new FakeTransport(transport_name);
+  }
+
+  void Connect_w(FakeTransportController* dest) {
+    // Simulate the exchange of candidates.
+    ConnectChannels_w();
+    dest->ConnectChannels_w();
+    for (auto& kv : transports()) {
+      FakeTransport* transport = static_cast<FakeTransport*>(kv.second);
+      transport->SetDestination(dest->GetTransport_w(kv.first));
+    }
+  }
+
+  void ConnectChannels_w() {
+    for (auto& kv : transports()) {
+      FakeTransport* transport = static_cast<FakeTransport*>(kv.second);
+      transport->ConnectChannels();
+    }
+  }
+
+ private:
+  bool fail_create_channel_;
+};
+
+}  // namespace cricket
+
+#endif  // WEBRTC_P2P_BASE_FAKETRANSPORTCONTROLLER_H_