modules/stream_out/chromecast/chromecast_communication.cpp

   1 /*****************************************************************************
   2  * chromecast_communication.cpp: Handle chromecast protocol messages
   3  *****************************************************************************
   4  * Copyright © 2014-2017 VideoLAN
   5  *
   6  * Authors: Adrien Maglo <magsoft@videolan.org>
   7  *          Jean-Baptiste Kempf <jb@videolan.org>
   8  *          Steve Lhomme <robux4@videolabs.io>
   9  *          Hugo Beauzée-Luyssen <hugo@beauzee.fr>
  10  *
  11  * This program is free software; you can redistribute it and/or modify it
  12  * under the terms of the GNU Lesser General Public License as published by
  13  * the Free Software Foundation; either version 2.1 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * along with this program; if not, write to the Free Software Foundation,
  23  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 #ifdef HAVE_CONFIG_H
  27 # include "config.h"
  28 #endif
  29
  30 #include "chromecast.h"
  31 #ifdef HAVE_POLL
  32 # include <poll.h>
  33 #endif
  34
  35 /* deadline regarding pings sent from receiver */
  36 #define PING_WAIT_TIME 6000
  37
  38 ChromecastCommunication::ChromecastCommunication( vlc_object_t* p_module, const char* targetIP, unsigned int devicePort )
  39     : m_module( p_module )
  40     , m_creds( NULL )
  41     , m_tls( NULL )
  42     , m_receiver_requestId( 0 )
  43     , m_requestId( 0 )
  44 {
  45     if (devicePort == 0)
  46         devicePort = CHROMECAST_CONTROL_PORT;
  47
  48     m_creds = vlc_tls_ClientCreate( m_module->obj.parent );
  49     if (m_creds == NULL)
  50         throw std::runtime_error( "Failed to create TLS client" );
  51
  52     m_tls = vlc_tls_SocketOpenTLS( m_creds, targetIP, devicePort, "tcps",
  53                                    NULL, NULL );
  54     if (m_tls == NULL)
  55     {
  56         vlc_tls_Delete(m_creds);
  57         throw std::runtime_error( "Failed to create client session" );
  58     }
  59
  60     char psz_localIP[NI_MAXNUMERICHOST];
  61     if (net_GetSockAddress( vlc_tls_GetFD(m_tls), psz_localIP, NULL ))
  62         throw std::runtime_error( "Cannot get local IP address" );
  63
  64     m_serverIp = psz_localIP;
  65 }
  66
  67 ChromecastCommunication::~ChromecastCommunication()
  68 {
  69     disconnect();
  70 }
  71
  72 void ChromecastCommunication::disconnect()
  73 {
  74     if ( m_tls != NULL )
  75     {
  76         vlc_tls_Close(m_tls);
  77         vlc_tls_Delete(m_creds);
  78         m_tls = NULL;
  79     }
  80 }
  81
  82 /**
  83  * @brief Build a CastMessage to send to the Chromecast
  84  * @param namespace_ the message namespace
  85  * @param payloadType the payload type (CastMessage_PayloadType_STRING or
  86  * CastMessage_PayloadType_BINARY
  87  * @param payload the payload
  88  * @param destinationId the destination idenifier
  89  * @return the generated CastMessage
  90  */
  91 int ChromecastCommunication::buildMessage(const std::string & namespace_,
  92                               const std::string & payload,
  93                               const std::string & destinationId,
  94                               castchannel::CastMessage_PayloadType payloadType)
  95 {
  96     castchannel::CastMessage msg;
  97
  98     msg.set_protocol_version(castchannel::CastMessage_ProtocolVersion_CASTV2_1_0);
  99     msg.set_namespace_(namespace_);
 100     msg.set_payload_type(payloadType);
 101     msg.set_source_id("sender-vlc");
 102     msg.set_destination_id(destinationId);
 103     if (payloadType == castchannel::CastMessage_PayloadType_STRING)
 104         msg.set_payload_utf8(payload);
 105     else // CastMessage_PayloadType_BINARY
 106         msg.set_payload_binary(payload);
 107
 108     return sendMessage(msg);
 109 }
 110
 111 /**
 112  * @brief Receive a data packet from the Chromecast
 113  * @param p_data the buffer in which to store the data
 114  * @param i_size the size of the buffer
 115  * @param i_timeout maximum time to wait for a packet, in millisecond
 116  * @param pb_timeout Output parameter that will contain true if no packet was received due to a timeout
 117  * @return the number of bytes received of -1 on error
 118  */
 119 ssize_t ChromecastCommunication::receive( uint8_t *p_data, size_t i_size, int i_timeout, bool *pb_timeout )
 120 {
 121     ssize_t i_received = 0;
 122     struct pollfd ufd[1];
 123     ufd[0].fd = vlc_tls_GetFD( m_tls );
 124     ufd[0].events = POLLIN;
 125
 126     struct iovec iov;
 127     iov.iov_base = p_data;
 128     iov.iov_len = i_size;
 129
 130     /* The Chromecast normally sends a PING command every 5 seconds or so.
 131      * If we do not receive one after 6 seconds, we send a PING.
 132      * If after this PING, we do not receive a PONG, then we consider the
 133      * connection as dead. */
 134     do
 135     {
 136         ssize_t i_ret = m_tls->readv( m_tls, &iov, 1 );
 137         if ( i_ret < 0 )
 138         {
 139 #ifdef _WIN32
 140             if ( WSAGetLastError() != WSAEWOULDBLOCK )
 141 #else
 142             if ( errno != EAGAIN )
 143 #endif
 144             {
 145                 return -1;
 146             }
 147             ssize_t val = vlc_poll_i11e(ufd, 1, i_timeout);
 148             if ( val < 0 )
 149                 return -1;
 150             else if ( val == 0 )
 151             {
 152                 *pb_timeout = true;
 153                 return i_received;
 154             }
 155             assert( ufd[0].revents & POLLIN );
 156             continue;
 157         }
 158         else if ( i_ret == 0 )
 159             return -1;
 160         assert( i_size >= (size_t)i_ret );
 161         i_size -= i_ret;
 162         i_received += i_ret;
 163         iov.iov_base = (uint8_t*)iov.iov_base + i_ret;
 164         iov.iov_len = i_size;
 165     } while ( i_size > 0 );
 166     return i_received;
 167 }
 168
 169
 170 /*****************************************************************************
 171  * Message preparation
 172  *****************************************************************************/
 173 int ChromecastCommunication::msgAuth()
 174 {
 175     castchannel::DeviceAuthMessage authMessage;
 176     authMessage.mutable_challenge();
 177
 178     return buildMessage(NAMESPACE_DEVICEAUTH, authMessage.SerializeAsString(),
 179                         DEFAULT_CHOMECAST_RECEIVER, castchannel::CastMessage_PayloadType_BINARY);
 180 }
 181
 182
 183 int ChromecastCommunication::msgPing()
 184 {
 185     std::string s("{\"type\":\"PING\"}");
 186     return buildMessage( NAMESPACE_HEARTBEAT, s, DEFAULT_CHOMECAST_RECEIVER );
 187 }
 188
 189
 190 int ChromecastCommunication::msgPong()
 191 {
 192     std::string s("{\"type\":\"PONG\"}");
 193     return buildMessage( NAMESPACE_HEARTBEAT, s, DEFAULT_CHOMECAST_RECEIVER );
 194 }
 195
 196 int ChromecastCommunication::msgConnect( const std::string& destinationId )
 197 {
 198     std::string s("{\"type\":\"CONNECT\"}");
 199     return buildMessage( NAMESPACE_CONNECTION, s, destinationId );
 200 }
 201
 202 int ChromecastCommunication::msgReceiverClose( const std::string& destinationId )
 203 {
 204     std::string s("{\"type\":\"CLOSE\"}");
 205     return buildMessage( NAMESPACE_CONNECTION, s, destinationId );
 206 }
 207
 208 int ChromecastCommunication::msgReceiverGetStatus()
 209 {
 210     std::stringstream ss;
 211     ss << "{\"type\":\"GET_STATUS\","
 212        <<  "\"requestId\":" << m_receiver_requestId++ << "}";
 213
 214     return buildMessage( NAMESPACE_RECEIVER, ss.str(), DEFAULT_CHOMECAST_RECEIVER );
 215 }
 216
 217 int ChromecastCommunication::msgReceiverLaunchApp()
 218 {
 219     std::stringstream ss;
 220     ss << "{\"type\":\"LAUNCH\","
 221        <<  "\"appId\":\"" << APP_ID << "\","
 222        <<  "\"requestId\":" << m_receiver_requestId++ << "}";
 223
 224     return buildMessage( NAMESPACE_RECEIVER, ss.str(), DEFAULT_CHOMECAST_RECEIVER );
 225 }
 226
 227 int ChromecastCommunication::msgPlayerGetStatus( const std::string& destinationId )
 228 {
 229     std::stringstream ss;
 230     ss << "{\"type\":\"GET_STATUS\","
 231        <<  "\"requestId\":" << m_requestId++
 232        << "}";
 233
 234     return pushMediaPlayerMessage( destinationId, ss );
 235 }
 236
 237 std::string ChromecastCommunication::GetMedia( unsigned int i_port,
 238                                                const std::string& mime,
 239                                                const vlc_meta_t *p_meta )
 240 {
 241     std::stringstream ss;
 242
 243     bool b_music = strncmp(mime.c_str(), "audio", strlen("audio")) == 0;
 244
 245     const char *psz_title = NULL;
 246     const char *psz_artwork = NULL;
 247     const char *psz_artist = NULL;
 248     const char *psz_album = NULL;
 249     const char *psz_albumartist = NULL;
 250     const char *psz_tracknumber = NULL;
 251     const char *psz_discnumber = NULL;
 252
 253     if( p_meta )
 254     {
 255         psz_title = vlc_meta_Get( p_meta, vlc_meta_Title );
 256         psz_artwork = vlc_meta_Get( p_meta, vlc_meta_ArtworkURL );
 257
 258         if( b_music && psz_title )
 259         {
 260             psz_artist = vlc_meta_Get( p_meta, vlc_meta_Artist );
 261             psz_album = vlc_meta_Get( p_meta, vlc_meta_Album );
 262             psz_albumartist = vlc_meta_Get( p_meta, vlc_meta_AlbumArtist );
 263             psz_tracknumber = vlc_meta_Get( p_meta, vlc_meta_TrackNumber );
 264             psz_discnumber = vlc_meta_Get( p_meta, vlc_meta_DiscNumber );
 265         }
 266         if( !psz_title )
 267         {
 268             psz_title = vlc_meta_Get( p_meta, vlc_meta_NowPlaying );
 269             if( !psz_title )
 270                 psz_title = vlc_meta_Get( p_meta, vlc_meta_ESNowPlaying );
 271         }
 272
 273         if ( psz_title )
 274         {
 275             ss << "\"metadata\":{"
 276                << " \"metadataType\":" << ( b_music ? "3" : "0" )
 277                << ",\"title\":\"" << psz_title << "\"";
 278             if( b_music )
 279             {
 280                 if( psz_artist )
 281                     ss << ",\"artist\":\"" << psz_artist << "\"";
 282                 if( psz_album )
 283                     ss << ",\"album\":\"" << psz_album << "\"";
 284                 if( psz_albumartist )
 285                     ss << ",\"albumArtist\":\"" << psz_albumartist << "\"";
 286                 if( psz_tracknumber )
 287                     ss << ",\"trackNumber\":\"" << psz_tracknumber << "\"";
 288                 if( psz_discnumber )
 289                     ss << ",\"discNumber\":\"" << psz_discnumber << "\"";
 290             }
 291
 292             if ( psz_artwork && !strncmp( psz_artwork, "http", 4 ) )
 293                 ss << ",\"images\":[{\"url\":\"" << psz_artwork << "\"}]";
 294
 295             ss << "},";
 296         }
 297     }
 298
 299     std::stringstream chromecast_url;
 300     chromecast_url << "http://" << m_serverIp << ":" << i_port << "/stream";
 301
 302     msg_Dbg( m_module, "s_chromecast_url: %s", chromecast_url.str().c_str());
 303
 304     ss << "\"contentId\":\"" << chromecast_url.str() << "\""
 305        << ",\"streamType\":\"LIVE\""
 306        << ",\"contentType\":\"" << mime << "\"";
 307
 308     return ss.str();
 309 }
 310
 311 int ChromecastCommunication::msgPlayerLoad( const std::string& destinationId, unsigned int i_port,
 312                                              const std::string& mime, const vlc_meta_t *p_meta )
 313 {
 314     std::stringstream ss;
 315     ss << "{\"type\":\"LOAD\","
 316        <<  "\"media\":{" << GetMedia( i_port, mime, p_meta ) << "},"
 317        <<  "\"autoplay\":\"false\","
 318        <<  "\"requestId\":" << m_requestId++
 319        << "}";
 320
 321     return pushMediaPlayerMessage( destinationId, ss );
 322 }
 323
 324 int ChromecastCommunication::msgPlayerPlay( const std::string& destinationId, int64_t mediaSessionId )
 325 {
 326     assert(mediaSessionId != 0);
 327
 328     std::stringstream ss;
 329     ss << "{\"type\":\"PLAY\","
 330        <<  "\"mediaSessionId\":" << mediaSessionId << ","
 331        <<  "\"requestId\":" << m_requestId++
 332        << "}";
 333
 334     return pushMediaPlayerMessage( destinationId, ss );
 335 }
 336
 337 int ChromecastCommunication::msgPlayerStop( const std::string& destinationId, int64_t mediaSessionId )
 338 {
 339     assert(mediaSessionId != 0);
 340
 341     std::stringstream ss;
 342     ss << "{\"type\":\"STOP\","
 343        <<  "\"mediaSessionId\":" << mediaSessionId << ","
 344        <<  "\"requestId\":" << m_requestId++
 345        << "}";
 346
 347     return pushMediaPlayerMessage( destinationId, ss );
 348 }
 349
 350 int ChromecastCommunication::msgPlayerPause( const std::string& destinationId, int64_t mediaSessionId )
 351 {
 352     assert(mediaSessionId != 0);
 353
 354     std::stringstream ss;
 355     ss << "{\"type\":\"PAUSE\","
 356        <<  "\"mediaSessionId\":" << mediaSessionId << ","
 357        <<  "\"requestId\":" << m_requestId++
 358        << "}";
 359
 360     return pushMediaPlayerMessage( destinationId, ss );
 361 }
 362
 363 int ChromecastCommunication::msgPlayerSetVolume( const std::string& destinationId, int64_t mediaSessionId, float f_volume, bool b_mute )
 364 {
 365     assert(mediaSessionId != 0);
 366
 367     if ( f_volume < 0.0 || f_volume > 1.0)
 368         return VLC_EGENERIC;
 369
 370     std::stringstream ss;
 371     ss << "{\"type\":\"SET_VOLUME\","
 372        <<  "\"volume\":{\"level\":" << f_volume << ",\"muted\":" << ( b_mute ? "true" : "false" ) << "},"
 373        <<  "\"mediaSessionId\":" << mediaSessionId << ","
 374        <<  "\"requestId\":" << m_requestId++
 375        << "}";
 376
 377     return pushMediaPlayerMessage( destinationId, ss );
 378 }
 379
 380 int ChromecastCommunication::msgPlayerSeek( const std::string& destinationId, int64_t mediaSessionId, const std::string& currentTime )
 381 {
 382     assert(mediaSessionId != 0);
 383
 384     std::stringstream ss;
 385     ss << "{\"type\":\"SEEK\","
 386        <<  "\"currentTime\":" << currentTime << ","
 387        <<  "\"mediaSessionId\":" << mediaSessionId << ","
 388        <<  "\"requestId\":" << m_requestId++
 389        << "}";
 390
 391     return pushMediaPlayerMessage( destinationId, ss );
 392 }
 393
 394 /**
 395  * @brief Send a message to the Chromecast
 396  * @param msg the CastMessage to send
 397  * @return vlc error code
 398  */
 399 int ChromecastCommunication::sendMessage( const castchannel::CastMessage &msg )
 400 {
 401     int i_size = msg.ByteSize();
 402     uint8_t *p_data = new(std::nothrow) uint8_t[PACKET_HEADER_LEN + i_size];
 403     if (p_data == NULL)
 404         return VLC_ENOMEM;
 405
 406 #ifndef NDEBUG
 407     msg_Dbg( m_module, "sendMessage: %s->%s %s", msg.namespace_().c_str(), msg.destination_id().c_str(), msg.payload_utf8().c_str());
 408 #endif
 409
 410     SetDWBE(p_data, i_size);
 411     msg.SerializeWithCachedSizesToArray(p_data + PACKET_HEADER_LEN);
 412
 413     int i_ret = vlc_tls_Write(m_tls, p_data, PACKET_HEADER_LEN + i_size);
 414     delete[] p_data;
 415     if (i_ret == PACKET_HEADER_LEN + i_size)
 416         return VLC_SUCCESS;
 417
 418     msg_Warn( m_module, "failed to send message %s (%s)", msg.payload_utf8().c_str(), strerror( errno ) );
 419
 420     return VLC_EGENERIC;
 421 }
 422
 423 int ChromecastCommunication::pushMediaPlayerMessage( const std::string& destinationId, const std::stringstream & payload )
 424 {
 425     assert(!destinationId.empty());
 426     return buildMessage( NAMESPACE_MEDIA, payload.str(), destinationId );
 427 }