1/*
2 * libjingle
3 * Copyright 2012 Google Inc. and Robin Seggelmann
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 *  1. Redistributions of source code must retain the above copyright notice,
9 *     this list of conditions and the following disclaimer.
10 *  2. Redistributions in binary form must reproduce the above copyright notice,
11 *     this list of conditions and the following disclaimer in the documentation
12 *     and/or other materials provided with the distribution.
13 *  3. The name of the author may not be used to endorse or promote products
14 *     derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#ifndef TALK_MEDIA_SCTP_SCTPDATAENGINE_H_
29#define TALK_MEDIA_SCTP_SCTPDATAENGINE_H_
30
31#include <errno.h>
32#include <string>
33#include <vector>
34
35namespace cricket {
36// Some ERRNO values get re-#defined to WSA* equivalents in some talk/
37// headers.  We save the original ones in an enum.
38enum PreservedErrno {
39  SCTP_EINPROGRESS = EINPROGRESS,
40  SCTP_EWOULDBLOCK = EWOULDBLOCK
41};
42}  // namespace cricket
43
44#include "talk/media/base/codec.h"
45#include "talk/media/base/mediachannel.h"
46#include "talk/media/base/mediaengine.h"
47#include "webrtc/base/buffer.h"
48#include "webrtc/base/scoped_ptr.h"
49
50// Defined by "usrsctplib/usrsctp.h"
51struct sockaddr_conn;
52struct sctp_assoc_change;
53struct sctp_stream_reset_event;
54// Defined by <sys/socket.h>
55struct socket;
56namespace cricket {
57// The highest stream ID (Sid) that SCTP allows, and the number of streams we
58// tell SCTP we're going to use.
59const uint32_t kMaxSctpSid = 1023;
60
61// This is the default SCTP port to use. It is passed along the wire and the
62// connectee and connector must be using the same port. It is not related to the
63// ports at the IP level. (Corresponds to: sockaddr_conn.sconn_port in
64// usrsctp.h)
65const int kSctpDefaultPort = 5000;
66
67class SctpDataMediaChannel;
68
69// A DataEngine that interacts with usrsctp.
70//
71// From channel calls, data flows like this:
72// [worker thread (although it can in princple be another thread)]
73//  1.  SctpDataMediaChannel::SendData(data)
74//  2.  usrsctp_sendv(data)
75// [worker thread returns; sctp thread then calls the following]
76//  3.  OnSctpOutboundPacket(wrapped_data)
77// [sctp thread returns having posted a message for the worker thread]
78//  4.  SctpDataMediaChannel::OnMessage(wrapped_data)
79//  5.  SctpDataMediaChannel::OnPacketFromSctpToNetwork(wrapped_data)
80//  6.  NetworkInterface::SendPacket(wrapped_data)
81//  7.  ... across network ... a packet is sent back ...
82//  8.  SctpDataMediaChannel::OnPacketReceived(wrapped_data)
83//  9.  usrsctp_conninput(wrapped_data)
84// [worker thread returns; sctp thread then calls the following]
85//  10.  OnSctpInboundData(data)
86// [sctp thread returns having posted a message fot the worker thread]
87//  11. SctpDataMediaChannel::OnMessage(inboundpacket)
88//  12. SctpDataMediaChannel::OnInboundPacketFromSctpToChannel(inboundpacket)
89//  13. SctpDataMediaChannel::OnDataFromSctpToChannel(data)
90//  14. SctpDataMediaChannel::SignalDataReceived(data)
91// [from the same thread, methods registered/connected to
92//  SctpDataMediaChannel are called with the recieved data]
93class SctpDataEngine : public DataEngineInterface, public sigslot::has_slots<> {
94 public:
95  SctpDataEngine();
96  virtual ~SctpDataEngine();
97
98  virtual DataMediaChannel* CreateChannel(DataChannelType data_channel_type);
99
100  virtual const std::vector<DataCodec>& data_codecs() { return codecs_; }
101
102  static int SendThresholdCallback(struct socket* sock, uint32_t sb_free);
103
104 private:
105  static int usrsctp_engines_count;
106  std::vector<DataCodec> codecs_;
107
108  static SctpDataMediaChannel* GetChannelFromSocket(struct socket* sock);
109};
110
111// TODO(ldixon): Make into a special type of TypedMessageData.
112// Holds data to be passed on to a channel.
113struct SctpInboundPacket;
114
115class SctpDataMediaChannel : public DataMediaChannel,
116                             public rtc::MessageHandler {
117 public:
118  // DataMessageType is used for the SCTP "Payload Protocol Identifier", as
119  // defined in http://tools.ietf.org/html/rfc4960#section-14.4
120  //
121  // For the list of IANA approved values see:
122  // http://www.iana.org/assignments/sctp-parameters/sctp-parameters.xml
123  // The value is not used by SCTP itself. It indicates the protocol running
124  // on top of SCTP.
125  enum PayloadProtocolIdentifier {
126    PPID_NONE = 0,  // No protocol is specified.
127    // Matches the PPIDs in mozilla source and
128    // https://datatracker.ietf.org/doc/draft-ietf-rtcweb-data-protocol Sec. 9
129    // They're not yet assigned by IANA.
130    PPID_CONTROL = 50,
131    PPID_BINARY_PARTIAL = 52,
132    PPID_BINARY_LAST = 53,
133    PPID_TEXT_PARTIAL = 54,
134    PPID_TEXT_LAST = 51
135  };
136
137  typedef std::set<uint32_t> StreamSet;
138
139  // Given a thread which will be used to post messages (received data) to this
140  // SctpDataMediaChannel instance.
141  explicit SctpDataMediaChannel(rtc::Thread* thread);
142  virtual ~SctpDataMediaChannel();
143
144  // When SetSend is set to true, connects. When set to false, disconnects.
145  // Calling: "SetSend(true); SetSend(false); SetSend(true);" will connect,
146  // disconnect, and reconnect.
147  virtual bool SetSend(bool send);
148  // Unless SetReceive(true) is called, received packets will be discarded.
149  virtual bool SetReceive(bool receive);
150
151  virtual bool SetSendParameters(const DataSendParameters& params);
152  virtual bool SetRecvParameters(const DataRecvParameters& params);
153  virtual bool AddSendStream(const StreamParams& sp);
154  virtual bool RemoveSendStream(uint32_t ssrc);
155  virtual bool AddRecvStream(const StreamParams& sp);
156  virtual bool RemoveRecvStream(uint32_t ssrc);
157
158  // Called when Sctp gets data. The data may be a notification or data for
159  // OnSctpInboundData. Called from the worker thread.
160  virtual void OnMessage(rtc::Message* msg);
161  // Send data down this channel (will be wrapped as SCTP packets then given to
162  // sctp that will then post the network interface by OnMessage).
163  // Returns true iff successful data somewhere on the send-queue/network.
164  virtual bool SendData(const SendDataParams& params,
165                        const rtc::Buffer& payload,
166                        SendDataResult* result = NULL);
167  // A packet is received from the network interface. Posted to OnMessage.
168  virtual void OnPacketReceived(rtc::Buffer* packet,
169                                const rtc::PacketTime& packet_time);
170
171  // Exposed to allow Post call from c-callbacks.
172  rtc::Thread* worker_thread() const { return worker_thread_; }
173
174  // Many of these things are unused by SCTP, but are needed to fulfill
175  // the MediaChannel interface.
176  virtual void OnRtcpReceived(rtc::Buffer* packet,
177                              const rtc::PacketTime& packet_time) {}
178  virtual void OnReadyToSend(bool ready) {}
179
180  void OnSendThresholdCallback();
181  // Helper for debugging.
182  void set_debug_name(const std::string& debug_name) {
183    debug_name_ = debug_name;
184  }
185  const std::string& debug_name() const { return debug_name_; }
186  const struct socket* socket() const { return sock_; }
187 private:
188  sockaddr_conn GetSctpSockAddr(int port);
189
190  bool SetSendCodecs(const std::vector<DataCodec>& codecs);
191  bool SetRecvCodecs(const std::vector<DataCodec>& codecs);
192
193  // Creates the socket and connects. Sets sending_ to true.
194  bool Connect();
195  // Closes the socket. Sets sending_ to false.
196  void Disconnect();
197
198  // Returns false when openning the socket failed; when successfull sets
199  // sending_ to true
200  bool OpenSctpSocket();
201  // Sets sending_ to false and sock_ to NULL.
202  void CloseSctpSocket();
203
204  // Sends a SCTP_RESET_STREAM for all streams in closing_ssids_.
205  bool SendQueuedStreamResets();
206
207  // Adds a stream.
208  bool AddStream(const StreamParams &sp);
209  // Queues a stream for reset.
210  bool ResetStream(uint32_t ssrc);
211
212  // Called by OnMessage to send packet on the network.
213  void OnPacketFromSctpToNetwork(rtc::Buffer* buffer);
214  // Called by OnMessage to decide what to do with the packet.
215  void OnInboundPacketFromSctpToChannel(SctpInboundPacket* packet);
216  void OnDataFromSctpToChannel(const ReceiveDataParams& params,
217                               rtc::Buffer* buffer);
218  void OnNotificationFromSctp(rtc::Buffer* buffer);
219  void OnNotificationAssocChange(const sctp_assoc_change& change);
220
221  void OnStreamResetEvent(const struct sctp_stream_reset_event* evt);
222
223  // Responsible for marshalling incoming data to the channels listeners, and
224  // outgoing data to the network interface.
225  rtc::Thread* worker_thread_;
226  // The local and remote SCTP port to use. These are passed along the wire
227  // and the listener and connector must be using the same port. It is not
228  // related to the ports at the IP level.  If set to -1, we default to
229  // kSctpDefaultPort.
230  int local_port_;
231  int remote_port_;
232  struct socket* sock_;  // The socket created by usrsctp_socket(...).
233
234  // sending_ is true iff there is a connected socket.
235  bool sending_;
236  // receiving_ controls whether inbound packets are thrown away.
237  bool receiving_;
238
239  // When a data channel opens a stream, it goes into open_streams_.  When we
240  // want to close it, the stream's ID goes into queued_reset_streams_.  When
241  // we actually transmit a RE-CONFIG chunk with that stream ID, the ID goes
242  // into sent_reset_streams_.  When we get a response RE-CONFIG chunk back
243  // acknowledging the reset, we remove the stream ID from
244  // sent_reset_streams_.  We use sent_reset_streams_ to differentiate
245  // between acknowledgment RE-CONFIG and peer-initiated RE-CONFIGs.
246  StreamSet open_streams_;
247  StreamSet queued_reset_streams_;
248  StreamSet sent_reset_streams_;
249
250  // A human-readable name for debugging messages.
251  std::string debug_name_;
252};
253
254}  // namespace cricket
255
256#endif  // TALK_MEDIA_SCTP_SCTPDATAENGINE_H_
257