git.sesse.net Git - ffmpeg/blob - libavformat/mmst.c

   1 /*
   2  * MMS protocol over TCP
   3  * Copyright (c) 2006,2007 Ryan Martell
   4  * Copyright (c) 2007 Björn Axelsson
   5  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
   6  *
   7  * This file is part of FFmpeg.
   8  *
   9  * FFmpeg is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * FFmpeg is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with FFmpeg; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 /* References
  25  * MMS protocol specification:
  26  *  [1]http://msdn.microsoft.com/en-us/library/cc234711(PROT.10).aspx
  27  * ASF specification. Revision 01.20.03.
  28  *  [2]http://msdn.microsoft.com/en-us/library/bb643323.aspx
  29  */
  30
  31 #include "avformat.h"
  32 #include "internal.h"
  33 #include "libavutil/intreadwrite.h"
  34 #include "libavcodec/bytestream.h"
  35 #include "network.h"
  36 #include "asf.h"
  37
  38 #define LOCAL_ADDRESS 0xc0a80081    // FIXME get and use correct local ip address.
  39 #define LOCAL_PORT    1037          // as above.
  40 /** Client to server packet types. */
  41 typedef enum {
  42     CS_PKT_INITIAL                  = 0x01,
  43     CS_PKT_PROTOCOL_SELECT          = 0x02,
  44     CS_PKT_MEDIA_FILE_REQUEST       = 0x05,
  45     CS_PKT_START_FROM_PKT_ID        = 0x07,
  46     CS_PKT_STREAM_PAUSE             = 0x09,
  47     CS_PKT_STREAM_CLOSE             = 0x0d,
  48     CS_PKT_MEDIA_HEADER_REQUEST     = 0x15,
  49     CS_PKT_TIMING_DATA_REQUEST      = 0x18,
  50     CS_PKT_USER_PASSWORD            = 0x1a,
  51     CS_PKT_KEEPALIVE                = 0x1b,
  52     CS_PKT_STREAM_ID_REQUEST        = 0x33,
  53 } MMSCSPacketType;
  54
  55 /** Server to client packet types. */
  56 typedef enum {
  57     /** Control packets. */
  58     /*@{*/
  59     SC_PKT_CLIENT_ACCEPTED          = 0x01,
  60     SC_PKT_PROTOCOL_ACCEPTED        = 0x02,
  61     SC_PKT_PROTOCOL_FAILED          = 0x03,
  62     SC_PKT_MEDIA_PKT_FOLLOWS        = 0x05,
  63     SC_PKT_MEDIA_FILE_DETAILS       = 0x06,
  64     SC_PKT_HEADER_REQUEST_ACCEPTED  = 0x11,
  65     SC_PKT_TIMING_TEST_REPLY        = 0x15,
  66     SC_PKT_PASSWORD_REQUIRED        = 0x1a,
  67     SC_PKT_KEEPALIVE                = 0x1b,
  68     SC_PKT_STREAM_STOPPED           = 0x1e,
  69     SC_PKT_STREAM_CHANGING          = 0x20,
  70     SC_PKT_STREAM_ID_ACCEPTED       = 0x21,
  71     /*@}*/
  72
  73     /** Pseudo packets. */
  74     /*@{*/
  75     SC_PKT_CANCEL                   = -1,
  76     SC_PKT_NO_DATA                  = -2,
  77     /*@}*/
  78
  79     /** Data packets. */
  80     /*@{*/
  81     SC_PKT_ASF_HEADER               = 0x010000,// make it bigger than 0xFF in case of
  82     SC_PKT_ASF_MEDIA                = 0x010001,// receiving false data packets.
  83     /*@}*/
  84 } MMSSCPacketType;
  85
  86 typedef struct {
  87     int id;
  88 }MMSStream;
  89
  90 typedef struct {
  91     int outgoing_packet_seq;             ///< Outgoing packet sequence number.
  92     char path[256];                      ///< Path of the resource being asked for.
  93     char host[128];                      ///< Host of the resources.
  94
  95     URLContext *mms_hd;                  ///< TCP connection handle
  96     MMSStream streams[MAX_STREAMS];
  97
  98     /** Buffer for outgoing packets. */
  99     /*@{*/
 100     uint8_t *write_out_ptr;              ///< Pointer for writting the buffer.
 101     uint8_t out_buffer[512];             ///< Buffer for outgoing packet.
 102     /*@}*/
 103
 104     /** Buffer for incoming packets. */
 105     /*@{*/
 106     uint8_t in_buffer[8192];             ///< Buffer for incoming packets.
 107     uint8_t *read_in_ptr;                ///< Pointer for reading from incoming buffer.
 108     int remaining_in_len;                ///< Reading length from incoming buffer.
 109     /*@}*/
 110
 111     int incoming_packet_seq;             ///< Incoming packet sequence number.
 112     int incoming_flags;                  ///< Incoming packet flags.
 113
 114     int packet_id;                       ///< Identifier for packets in the current stream.
 115     unsigned int header_packet_id;       ///< default is 2.
 116
 117     /** Internal handling of the ASF header */
 118     /*@{*/
 119     uint8_t *asf_header;                 ///< Stored ASF header.
 120     int asf_header_size;                 ///< Size of stored ASF header.
 121     int header_parsed;                   ///< The header has been received and parsed.
 122     int asf_packet_len;
 123     int asf_header_read_size;
 124     /*@}*/
 125
 126     int stream_num;                      ///< stream numbers.
 127     int is_playing;
 128 } MMSContext;
 129
 130 /** Create MMST command packet header */
 131 static void start_command_packet(MMSContext *mms, MMSCSPacketType packet_type)
 132 {
 133     mms->write_out_ptr = mms->out_buffer;
 134
 135     bytestream_put_le32(&mms->write_out_ptr, 1); // start sequence
 136     bytestream_put_le32(&mms->write_out_ptr, 0xb00bface);
 137     bytestream_put_le32(&mms->write_out_ptr, 0); // Length starts from after the protocol type bytes
 138     bytestream_put_le32(&mms->write_out_ptr, MKTAG('M','M','S',' '));
 139     bytestream_put_le32(&mms->write_out_ptr, 0);
 140     bytestream_put_le32(&mms->write_out_ptr, mms->outgoing_packet_seq++);
 141     bytestream_put_le64(&mms->write_out_ptr, 0); // timestamp
 142     bytestream_put_le32(&mms->write_out_ptr, 0);
 143     bytestream_put_le16(&mms->write_out_ptr, packet_type);
 144     bytestream_put_le16(&mms->write_out_ptr, 3); // direction to server
 145 }
 146
 147 /** Add prefixes to MMST command packet. */
 148 static void insert_command_prefixes(MMSContext *mms,
 149         uint32_t prefix1, uint32_t prefix2)
 150 {
 151     bytestream_put_le32(&mms->write_out_ptr, prefix1); // first prefix
 152     bytestream_put_le32(&mms->write_out_ptr, prefix2); // second prefix
 153 }
 154
 155 /** Send a prepared MMST command packet. */
 156 static int send_command_packet(MMSContext *mms)
 157 {
 158     int len= mms->write_out_ptr - mms->out_buffer;
 159     int exact_length = (len + 7) & ~7;
 160     int first_length= exact_length - 16;
 161     int len8= first_length/8;
 162     int write_result;
 163
 164     // update packet length fields.
 165     AV_WL32(mms->out_buffer + 8, first_length);
 166     AV_WL32(mms->out_buffer + 16, len8);
 167     AV_WL32(mms->out_buffer + 32, len8-2);
 168     memset(mms->write_out_ptr, 0, exact_length - len);
 169
 170     // write it out.
 171     write_result= url_write(mms->mms_hd, mms->out_buffer, exact_length);
 172     if(write_result != exact_length) {
 173         av_log(NULL, AV_LOG_ERROR,
 174                "Failed to write data of length %d: %d (%s)\n",
 175                exact_length, write_result,
 176                write_result < 0 ? strerror(write_result) :
 177                    "The server closed the connection");
 178         return AVERROR_IO;
 179     }
 180
 181     return 0;
 182 }
 183
 184 static void mms_put_utf16(MMSContext *mms, uint8_t *src)
 185 {
 186     ByteIOContext bic;
 187     int size = mms->write_out_ptr - mms->out_buffer;
 188     int len;
 189     init_put_byte(&bic, mms->write_out_ptr,
 190             sizeof(mms->out_buffer) - size, 1, NULL, NULL, NULL, NULL);
 191
 192     len = ff_put_str16_nolen(&bic, src);
 193     mms->write_out_ptr += len;
 194 }
 195
 196 static int send_time_test_data(MMSContext *mms)
 197 {
 198     start_command_packet(mms, CS_PKT_TIMING_DATA_REQUEST);
 199     insert_command_prefixes(mms, 0xf0f0f0f1, 0x0004000b);
 200     return send_command_packet(mms);
 201 }
 202
 203 static int send_protocol_select(MMSContext *mms)
 204 {
 205     char data_string[256];
 206
 207     start_command_packet(mms, CS_PKT_PROTOCOL_SELECT);
 208     insert_command_prefixes(mms, 0, 0xffffffff);
 209     bytestream_put_le32(&mms->write_out_ptr, 0);          // maxFunnelBytes
 210     bytestream_put_le32(&mms->write_out_ptr, 0x00989680); // maxbitRate
 211     bytestream_put_le32(&mms->write_out_ptr, 2);          // funnelMode
 212     snprintf(data_string, sizeof(data_string), "\\\\%d.%d.%d.%d\\%s\\%d",
 213             (LOCAL_ADDRESS>>24)&0xff,
 214             (LOCAL_ADDRESS>>16)&0xff,
 215             (LOCAL_ADDRESS>>8)&0xff,
 216             LOCAL_ADDRESS&0xff,
 217             "TCP",                                        // or UDP
 218             LOCAL_PORT);
 219
 220     mms_put_utf16(mms, data_string);
 221     return send_command_packet(mms);
 222 }
 223
 224 static int send_media_file_request(MMSContext *mms)
 225 {
 226     start_command_packet(mms, CS_PKT_MEDIA_FILE_REQUEST);
 227     insert_command_prefixes(mms, 1, 0xffffffff);
 228     bytestream_put_le32(&mms->write_out_ptr, 0);
 229     bytestream_put_le32(&mms->write_out_ptr, 0);
 230     mms_put_utf16(mms, mms->path + 1); // +1 for skip "/"
 231
 232     return send_command_packet(mms);
 233 }
 234
 235 static void handle_packet_stream_changing_type(MMSContext *mms)
 236 {
 237     dprintf(NULL, "Stream changing!\n");
 238
 239     // 40 is the packet header size, 7 is the prefix size.
 240     mms->header_packet_id= AV_RL32(mms->in_buffer + 40 + 7);
 241     dprintf(NULL, "Changed header prefix to 0x%x", mms->header_packet_id);
 242 }
 243
 244 static int send_keepalive_packet(MMSContext *mms)
 245 {
 246     // respond to a keepalive with a keepalive...
 247     start_command_packet(mms, CS_PKT_KEEPALIVE);
 248     insert_command_prefixes(mms, 1, 0x100FFFF);
 249     return send_command_packet(mms);
 250 }
 251
 252 /** Pad media packets smaller than max_packet_size and/or adjust read position
 253   * after a seek. */
 254 static void pad_media_packet(MMSContext *mms)
 255 {
 256     if(mms->remaining_in_len<mms->asf_packet_len) {
 257         int padding_size = mms->asf_packet_len - mms->remaining_in_len;
 258         memset(mms->in_buffer + mms->remaining_in_len, 0, padding_size);
 259         mms->remaining_in_len += padding_size;
 260     }
 261 }
 262
 263 /** Read incoming MMST media, header or command packet. */
 264 static MMSSCPacketType get_tcp_server_response(MMSContext *mms)
 265 {
 266     int read_result;
 267     MMSSCPacketType packet_type= -1;
 268
 269     for(;;) {
 270         read_result = url_read_complete(mms->mms_hd, mms->in_buffer, 8);
 271         if (read_result != 8) {
 272             if(read_result < 0) {
 273                 av_log(NULL, AV_LOG_ERROR,
 274                        "Error reading packet header: %d (%s)\n",
 275                        read_result, strerror(read_result));
 276                 packet_type = SC_PKT_CANCEL;
 277             } else {
 278                 av_log(NULL, AV_LOG_ERROR,
 279                        "The server closed the connection\n");
 280                 packet_type = SC_PKT_NO_DATA;
 281             }
 282             return packet_type;
 283         }
 284
 285             // handle command packet.
 286             if(AV_RL32(mms->in_buffer + 4)==0xb00bface) {
 287             int length_remaining, hr;
 288
 289                 mms->incoming_flags= mms->in_buffer[3];
 290                 read_result= url_read_complete(mms->mms_hd, mms->in_buffer+8, 4);
 291                 if(read_result != 4) {
 292                     av_log(NULL, AV_LOG_ERROR,
 293                            "Reading command packet length failed: %d (%s)\n",
 294                            read_result,
 295                            read_result < 0 ? strerror(read_result) :
 296                                "The server closed the connection");
 297                     return read_result < 0 ? read_result : AVERROR_IO;
 298                 }
 299
 300             length_remaining= AV_RL32(mms->in_buffer+8) + 4;
 301                     dprintf(NULL, "Length remaining is %d\n", length_remaining);
 302                     // read the rest of the packet.
 303                     if (length_remaining < 0
 304                         || length_remaining > sizeof(mms->in_buffer) - 12) {
 305                         av_log(NULL, AV_LOG_ERROR,
 306                                "Incoming packet length %d exceeds bufsize %zu\n",
 307                                length_remaining, sizeof(mms->in_buffer) - 12);
 308                         return AVERROR_INVALIDDATA;
 309                     }
 310                     read_result = url_read_complete(mms->mms_hd, mms->in_buffer + 12,
 311                                                   length_remaining) ;
 312                     if (read_result != length_remaining) {
 313                         av_log(NULL, AV_LOG_ERROR,
 314                                "Reading pkt data (length=%d) failed: %d (%s)\n",
 315                                length_remaining, read_result,
 316                                read_result < 0 ? strerror(read_result) :
 317                                    "The server closed the connection");
 318                         return read_result < 0 ? read_result : AVERROR_IO;
 319                     }
 320                     packet_type= AV_RL16(mms->in_buffer+36);
 321                     hr = AV_RL32(mms->in_buffer + 40);
 322                     if (hr) {
 323                         av_log(NULL, AV_LOG_ERROR,
 324                                "Server sent an error status code: 0x%08x\n",
 325                                hr);
 326                         return AVERROR_UNKNOWN;
 327                     }
 328             } else {
 329                 int length_remaining;
 330                 int packet_id_type;
 331                 int tmp;
 332
 333                 // note we cache the first 8 bytes,
 334                 // then fill up the buffer with the others
 335                 tmp                       = AV_RL16(mms->in_buffer + 6);
 336                 length_remaining          = (tmp - 8) & 0xffff;
 337                 mms->incoming_packet_seq  = AV_RL32(mms->in_buffer);
 338                 packet_id_type            = mms->in_buffer[4];
 339                 mms->incoming_flags       = mms->in_buffer[5];
 340
 341                 if (length_remaining < 0
 342                         || length_remaining > sizeof(mms->in_buffer) - 8) {
 343                     av_log(NULL, AV_LOG_ERROR,
 344                            "Data length %d is invalid or too large (max=%zu)\n",
 345                            length_remaining, sizeof(mms->in_buffer));
 346                     return AVERROR_INVALIDDATA;
 347                 }
 348                 mms->remaining_in_len    = length_remaining;
 349                 mms->read_in_ptr         = mms->in_buffer;
 350                 read_result= url_read_complete(mms->mms_hd, mms->in_buffer, length_remaining);
 351                 if(read_result != length_remaining) {
 352                     av_log(NULL, AV_LOG_ERROR,
 353                            "Failed to read packet data of size %d: %d (%s)\n",
 354                            length_remaining, read_result,
 355                            read_result < 0 ? strerror(read_result) :
 356                                "The server closed the connection");
 357                     return read_result < 0 ? read_result : AVERROR_IO;
 358                 }
 359
 360                     // if we successfully read everything.
 361                     if(packet_id_type == mms->header_packet_id) {
 362                         packet_type = SC_PKT_ASF_HEADER;
 363                         // Store the asf header
 364                         if(!mms->header_parsed) {
 365                             void *p = av_realloc(mms->asf_header,
 366                                               mms->asf_header_size
 367                                               + mms->remaining_in_len);
 368                             if (!p) {
 369                                 av_freep(&mms->asf_header);
 370                                 return AVERROR(ENOMEM);
 371                             }
 372                             mms->asf_header = p;
 373                             memcpy(mms->asf_header + mms->asf_header_size,
 374                                                  mms->read_in_ptr,
 375                                                  mms->remaining_in_len);
 376                             mms->asf_header_size += mms->remaining_in_len;
 377                         }
 378                         // 0x04 means asf header is sent in multiple packets.
 379                         if (mms->incoming_flags == 0x04)
 380                             continue;
 381                     } else if(packet_id_type == mms->packet_id) {
 382                         packet_type = SC_PKT_ASF_MEDIA;
 383                     } else {
 384                         dprintf(NULL, "packet id type %d is old.", packet_id_type);
 385                         continue;
 386                     }
 387             }
 388
 389             // preprocess some packet type
 390             if(packet_type == SC_PKT_KEEPALIVE) {
 391                 send_keepalive_packet(mms);
 392                 continue;
 393             } else if(packet_type == SC_PKT_STREAM_CHANGING) {
 394                 handle_packet_stream_changing_type(mms);
 395             } else if(packet_type == SC_PKT_ASF_MEDIA) {
 396                 pad_media_packet(mms);
 397             }
 398             return packet_type;
 399     }
 400 }
 401
 402 static int mms_safe_send_recv(MMSContext *mms,
 403                               int (*send_fun)(MMSContext *mms),
 404                               const MMSSCPacketType expect_type)
 405 {
 406     MMSSCPacketType type;
 407     if(send_fun) {
 408         int ret = send_fun(mms);
 409         if (ret < 0) {
 410             dprintf(NULL, "Send Packet error before expecting recv packet %d\n", expect_type);
 411             return ret;
 412         }
 413     }
 414
 415     if ((type = get_tcp_server_response(mms)) != expect_type) {
 416         av_log(NULL, AV_LOG_ERROR,
 417                "Corrupt stream (unexpected packet type 0x%x, expected 0x%x)\n",
 418                type, expect_type);
 419         return AVERROR_INVALIDDATA;
 420     } else {
 421         return 0;
 422     }
 423 }
 424
 425 static int send_media_header_request(MMSContext *mms)
 426 {
 427     start_command_packet(mms, CS_PKT_MEDIA_HEADER_REQUEST);
 428     insert_command_prefixes(mms, 1, 0);
 429     bytestream_put_le32(&mms->write_out_ptr, 0);
 430     bytestream_put_le32(&mms->write_out_ptr, 0x00800000);
 431     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff);
 432     bytestream_put_le32(&mms->write_out_ptr, 0);
 433     bytestream_put_le32(&mms->write_out_ptr, 0);
 434     bytestream_put_le32(&mms->write_out_ptr, 0);
 435
 436     // the media preroll value in milliseconds?
 437     bytestream_put_le32(&mms->write_out_ptr, 0);
 438     bytestream_put_le32(&mms->write_out_ptr, 0x40AC2000);
 439     bytestream_put_le32(&mms->write_out_ptr, 2);
 440     bytestream_put_le32(&mms->write_out_ptr, 0);
 441
 442     return send_command_packet(mms);
 443 }
 444
 445 /** Send the initial handshake. */
 446 static int send_startup_packet(MMSContext *mms)
 447 {
 448     char data_string[256];
 449     // SubscriberName is defined in MS specification linked below.
 450     // The guid value can be any valid value.
 451     // http://download.microsoft.com/
 452     // download/9/5/E/95EF66AF-9026-4BB0-A41D-A4F81802D92C/%5BMS-WMSP%5D.pdf
 453     snprintf(data_string, sizeof(data_string),
 454             "NSPlayer/7.0.0.1956; {%s}; Host: %s",
 455             "7E667F5D-A661-495E-A512-F55686DDA178", mms->host);
 456
 457     start_command_packet(mms, CS_PKT_INITIAL);
 458     insert_command_prefixes(mms, 0, 0x0004000b);
 459     bytestream_put_le32(&mms->write_out_ptr, 0x0003001c);
 460     mms_put_utf16(mms, data_string);
 461     return send_command_packet(mms);
 462 }
 463
 464 static int asf_header_parser(MMSContext *mms)
 465 {
 466     uint8_t *p = mms->asf_header;
 467     uint8_t *end;
 468     int flags, stream_id;
 469     mms->stream_num = 0;
 470
 471     if (mms->asf_header_size < sizeof(ff_asf_guid) * 2 + 22 ||
 472         memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) {
 473         av_log(NULL, AV_LOG_ERROR,
 474                "Corrupt stream (invalid ASF header, size=%d)\n",
 475                mms->asf_header_size);
 476         return AVERROR_INVALIDDATA;
 477     }
 478
 479     end = mms->asf_header + mms->asf_header_size;
 480
 481     p += sizeof(ff_asf_guid) + 14;
 482     while(end - p >= sizeof(ff_asf_guid) + 8) {
 483         uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid));
 484         if (!chunksize || chunksize > end - p) {
 485             av_log(NULL, AV_LOG_ERROR,
 486                    "Corrupt stream (header chunksize %"PRId64" is invalid)\n",
 487                    chunksize);
 488             return AVERROR_INVALIDDATA;
 489         }
 490         if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {
 491             /* read packet size */
 492             if (end - p > sizeof(ff_asf_guid) * 2 + 68) {
 493                 mms->asf_packet_len = AV_RL32(p + sizeof(ff_asf_guid) * 2 + 64);
 494                 if (mms->asf_packet_len <= 0 || mms->asf_packet_len > sizeof(mms->in_buffer)) {
 495                     av_log(NULL, AV_LOG_ERROR,
 496                            "Corrupt stream (too large pkt_len %d)\n",
 497                            mms->asf_packet_len);
 498                     return AVERROR_INVALIDDATA;
 499                 }
 500             }
 501         } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) {
 502             flags     = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24);
 503             stream_id = flags & 0x7F;
 504             //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size,
 505             //we can calcuate the packet size by stream_num.
 506             //Please see function send_stream_selection_request().
 507             if (mms->stream_num < MAX_STREAMS &&
 508                     46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) {
 509                 mms->streams[mms->stream_num].id = stream_id;
 510                 mms->stream_num++;
 511             } else {
 512                 av_log(NULL, AV_LOG_ERROR,
 513                        "Corrupt stream (too many A/V streams)\n");
 514                 return AVERROR_INVALIDDATA;
 515             }
 516         } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) {
 517             chunksize = 46; // see references [2] section 3.4. This should be set 46.
 518         }
 519         p += chunksize;
 520     }
 521
 522     return 0;
 523 }
 524
 525 /** Send MMST stream selection command based on the AVStream->discard values. */
 526 static int send_stream_selection_request(MMSContext *mms)
 527 {
 528     int i;
 529
 530     //  send the streams we want back...
 531     start_command_packet(mms, CS_PKT_STREAM_ID_REQUEST);
 532     bytestream_put_le32(&mms->write_out_ptr, mms->stream_num);         // stream nums
 533     for(i= 0; i<mms->stream_num; i++) {
 534         bytestream_put_le16(&mms->write_out_ptr, 0xffff);              // flags
 535         bytestream_put_le16(&mms->write_out_ptr, mms->streams[i].id);  // stream id
 536         bytestream_put_le16(&mms->write_out_ptr, 0);                   // selection
 537     }
 538     return send_command_packet(mms);
 539 }
 540
 541 static int read_data(MMSContext *mms, uint8_t *buf, const int buf_size)
 542 {
 543     int read_size;
 544     read_size = FFMIN(buf_size, mms->remaining_in_len);
 545     memcpy(buf, mms->read_in_ptr, read_size);
 546     mms->remaining_in_len -= read_size;
 547     mms->read_in_ptr      += read_size;
 548     return read_size;
 549 }
 550
 551 /** Read at most one media packet (or a whole header). */
 552 static int read_mms_packet(MMSContext *mms, uint8_t *buf, int buf_size)
 553 {
 554     int result = 0;
 555     int size_to_copy;
 556
 557     do {
 558         if(mms->asf_header_read_size < mms->asf_header_size && !mms->is_playing) {
 559             /* Read from ASF header buffer */
 560             size_to_copy= FFMIN(buf_size,
 561                                 mms->asf_header_size - mms->asf_header_read_size);
 562             memcpy(buf, mms->asf_header + mms->asf_header_read_size, size_to_copy);
 563             mms->asf_header_read_size += size_to_copy;
 564             result += size_to_copy;
 565             dprintf(NULL, "Copied %d bytes from stored header. left: %d\n",
 566                    size_to_copy, mms->asf_header_size - mms->asf_header_read_size);
 567             if (mms->asf_header_size == mms->asf_header_read_size) {
 568                 av_freep(&mms->asf_header);
 569                 mms->is_playing = 1;
 570             }
 571         } else if(mms->remaining_in_len) {
 572             /* Read remaining packet data to buffer.
 573              * the result can not be zero because remaining_in_len is positive.*/
 574             result = read_data(mms, buf, buf_size);
 575         } else {
 576             /* Read from network */
 577             int err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_MEDIA);
 578             if (err == 0) {
 579                 if(mms->remaining_in_len>mms->asf_packet_len) {
 580                     av_log(NULL, AV_LOG_ERROR,
 581                            "Incoming pktlen %d is larger than ASF pktsize %d\n",
 582                            mms->remaining_in_len, mms->asf_packet_len);
 583                     result= AVERROR_IO;
 584                 } else {
 585                     // copy the data to the packet buffer.
 586                     result = read_data(mms, buf, buf_size);
 587                     if (result == 0) {
 588                         dprintf(NULL, "read asf media paket size is zero!\n");
 589                         break;
 590                     }
 591                 }
 592             } else {
 593                 dprintf(NULL, "read packet error!\n");
 594                 break;
 595             }
 596         }
 597     } while(!result); // only return one packet.
 598     return result;
 599 }
 600
 601 static int send_close_packet(MMSContext *mms)
 602 {
 603     start_command_packet(mms, CS_PKT_STREAM_CLOSE);
 604     insert_command_prefixes(mms, 1, 1);
 605
 606     return send_command_packet(mms);
 607 }
 608
 609 /** Close the MMSH/MMST connection */
 610 static int mms_close(URLContext *h)
 611 {
 612     MMSContext *mms = (MMSContext *)h->priv_data;
 613
 614     if(mms->mms_hd) {
 615         send_close_packet(mms);
 616         url_close(mms->mms_hd);
 617     }
 618
 619     /* free all separately allocated pointers in mms */
 620     av_free(mms->asf_header);
 621     av_freep(&h->priv_data);
 622
 623     return 0;
 624 }
 625
 626 static int mms_open(URLContext *h, const char *uri, int flags)
 627 {
 628     MMSContext *mms;
 629     int port, err;
 630     char tcpname[256];
 631
 632     h->is_streamed = 1;
 633     mms = h->priv_data = av_mallocz(sizeof(MMSContext));
 634     if (!h->priv_data)
 635         return AVERROR(ENOMEM);
 636
 637     // only for MMS over TCP, so set proto = NULL
 638     av_url_split(NULL, 0, NULL, 0,
 639             mms->host, sizeof(mms->host), &port, mms->path,
 640             sizeof(mms->path), uri);
 641
 642     if(port<0)
 643         port = 1755; // defaut mms protocol port
 644
 645     // establish tcp connection.
 646     ff_url_join(tcpname, sizeof(tcpname), "tcp", NULL, mms->host, port, NULL);
 647     err = url_open(&mms->mms_hd, tcpname, URL_RDWR);
 648     if (err)
 649         goto fail;
 650
 651     mms->packet_id        = 3;          // default, initial value.
 652     mms->header_packet_id = 2;          // default, initial value.
 653     err = mms_safe_send_recv(mms, send_startup_packet, SC_PKT_CLIENT_ACCEPTED);
 654     if (err)
 655         goto fail;
 656     err = mms_safe_send_recv(mms, send_time_test_data, SC_PKT_TIMING_TEST_REPLY);
 657     if (err)
 658         goto fail;
 659     err = mms_safe_send_recv(mms, send_protocol_select, SC_PKT_PROTOCOL_ACCEPTED);
 660     if (err)
 661         goto fail;
 662     err = mms_safe_send_recv(mms, send_media_file_request, SC_PKT_MEDIA_FILE_DETAILS);
 663     if (err)
 664         goto fail;
 665     err = mms_safe_send_recv(mms, send_media_header_request, SC_PKT_HEADER_REQUEST_ACCEPTED);
 666     if (err)
 667         goto fail;
 668     err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_HEADER);
 669     if (err)
 670         goto fail;
 671     if((mms->incoming_flags != 0X08) && (mms->incoming_flags != 0X0C))
 672         goto fail;
 673     err = asf_header_parser(mms);
 674     if (err) {
 675         dprintf(NULL, "asf header parsed failed!\n");
 676         goto fail;
 677     }
 678     mms->header_parsed = 1;
 679
 680     if (!mms->asf_packet_len || !mms->stream_num)
 681         goto fail;
 682
 683     dprintf(NULL, "Leaving open (success)\n");
 684     return 0;
 685 fail:
 686     mms_close(h);
 687     dprintf(NULL, "Leaving open (failure: %d)\n", err);
 688     return err;
 689 }
 690
 691 static int send_media_packet_request(MMSContext *mms)
 692 {
 693     start_command_packet(mms, CS_PKT_START_FROM_PKT_ID);
 694     insert_command_prefixes(mms, 1, 0x0001FFFF);
 695     bytestream_put_le64(&mms->write_out_ptr, 0);          // seek timestamp
 696     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // unknown
 697     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // packet offset
 698     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
 699     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
 700     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
 701     bytestream_put_byte(&mms->write_out_ptr, 0x00);       // stream time limit flag
 702
 703     mms->packet_id++;                                     // new packet_id
 704     bytestream_put_le32(&mms->write_out_ptr, mms->packet_id);
 705     return send_command_packet(mms);
 706 }
 707
 708
 709 static void clear_stream_buffers(MMSContext *mms)
 710 {
 711     mms->remaining_in_len = 0;
 712     mms->read_in_ptr      = mms->in_buffer;
 713 }
 714
 715 /** Read ASF data through the protocol. */
 716 static int mms_read(URLContext *h, uint8_t *buf, int size)
 717 {
 718     /* TODO: see tcp.c:tcp_read() about a possible timeout scheme */
 719     MMSContext *mms = h->priv_data;
 720     int result = 0;
 721
 722     /* Since we read the header at open(), this shouldn't be possible */
 723     assert(mms->header_parsed);
 724
 725     if (!mms->is_playing) {
 726         dprintf(NULL, "mms_read() before play().\n");
 727         clear_stream_buffers(mms);
 728         result = mms_safe_send_recv(mms, send_stream_selection_request, SC_PKT_STREAM_ID_ACCEPTED);
 729         if (result)
 730             return result;
 731         // send media packet request
 732         result = mms_safe_send_recv(mms, send_media_packet_request, SC_PKT_MEDIA_PKT_FOLLOWS);
 733         if (result) {
 734             return result;
 735         }
 736     }
 737     return read_mms_packet(mms, buf, size);
 738 }
 739
 740 URLProtocol mmst_protocol = {
 741     "mmst",
 742     mms_open,
 743     mms_read,
 744     NULL, // write
 745     NULL, // seek
 746     mms_close,
 747 };