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         dprintf(NULL, "url_write returned: %d != %d\n",
 174                 write_result, exact_length);
 175         return AVERROR_IO;
 176     }
 177
 178     return 0;
 179 }
 180
 181 static void mms_put_utf16(MMSContext *mms, uint8_t *src)
 182 {
 183     ByteIOContext bic;
 184     int size = mms->write_out_ptr - mms->out_buffer;
 185     int len;
 186     init_put_byte(&bic, mms->write_out_ptr,
 187             sizeof(mms->out_buffer) - size, 1, NULL, NULL, NULL, NULL);
 188
 189     len = ff_put_str16_nolen(&bic, src);
 190     mms->write_out_ptr += len;
 191 }
 192
 193 static int send_time_test_data(MMSContext *mms)
 194 {
 195     start_command_packet(mms, CS_PKT_TIMING_DATA_REQUEST);
 196     insert_command_prefixes(mms, 0xf0f0f0f1, 0x0004000b);
 197     return send_command_packet(mms);
 198 }
 199
 200 static int send_protocol_select(MMSContext *mms)
 201 {
 202     char data_string[256];
 203
 204     start_command_packet(mms, CS_PKT_PROTOCOL_SELECT);
 205     insert_command_prefixes(mms, 0, 0xffffffff);
 206     bytestream_put_le32(&mms->write_out_ptr, 0);          // maxFunnelBytes
 207     bytestream_put_le32(&mms->write_out_ptr, 0x00989680); // maxbitRate
 208     bytestream_put_le32(&mms->write_out_ptr, 2);          // funnelMode
 209     snprintf(data_string, sizeof(data_string), "\\\\%d.%d.%d.%d\\%s\\%d",
 210             (LOCAL_ADDRESS>>24)&0xff,
 211             (LOCAL_ADDRESS>>16)&0xff,
 212             (LOCAL_ADDRESS>>8)&0xff,
 213             LOCAL_ADDRESS&0xff,
 214             "TCP",                                        // or UDP
 215             LOCAL_PORT);
 216
 217     mms_put_utf16(mms, data_string);
 218     return send_command_packet(mms);
 219 }
 220
 221 static int send_media_file_request(MMSContext *mms)
 222 {
 223     start_command_packet(mms, CS_PKT_MEDIA_FILE_REQUEST);
 224     insert_command_prefixes(mms, 1, 0xffffffff);
 225     bytestream_put_le32(&mms->write_out_ptr, 0);
 226     bytestream_put_le32(&mms->write_out_ptr, 0);
 227     mms_put_utf16(mms, mms->path + 1); // +1 for skip "/"
 228
 229     return send_command_packet(mms);
 230 }
 231
 232 static void handle_packet_stream_changing_type(MMSContext *mms)
 233 {
 234     dprintf(NULL, "Stream changing!\n");
 235
 236     // 40 is the packet header size, 7 is the prefix size.
 237     mms->header_packet_id= AV_RL32(mms->in_buffer + 40 + 7);
 238     dprintf(NULL, "Changed header prefix to 0x%x", mms->header_packet_id);
 239 }
 240
 241 static int send_keepalive_packet(MMSContext *mms)
 242 {
 243     // respond to a keepalive with a keepalive...
 244     start_command_packet(mms, CS_PKT_KEEPALIVE);
 245     insert_command_prefixes(mms, 1, 0x100FFFF);
 246     return send_command_packet(mms);
 247 }
 248
 249 /** Pad media packets smaller than max_packet_size and/or adjust read position
 250   * after a seek. */
 251 static void pad_media_packet(MMSContext *mms)
 252 {
 253     if(mms->remaining_in_len<mms->asf_packet_len) {
 254         int padding_size = mms->asf_packet_len - mms->remaining_in_len;
 255         memset(mms->in_buffer + mms->remaining_in_len, 0, padding_size);
 256         mms->remaining_in_len += padding_size;
 257     }
 258 }
 259
 260 /** Read incoming MMST media, header or command packet. */
 261 static MMSSCPacketType get_tcp_server_response(MMSContext *mms)
 262 {
 263     int read_result;
 264     MMSSCPacketType packet_type= -1;
 265
 266     for(;;) {
 267         if((read_result= url_read_complete(mms->mms_hd, mms->in_buffer, 8))==8) {
 268             // handle command packet.
 269             if(AV_RL32(mms->in_buffer + 4)==0xb00bface) {
 270                 mms->incoming_flags= mms->in_buffer[3];
 271                 read_result= url_read_complete(mms->mms_hd, mms->in_buffer+8, 4);
 272                 if(read_result == 4) {
 273                     int length_remaining= AV_RL32(mms->in_buffer+8) + 4;
 274                     int hr;
 275
 276                     dprintf(NULL, "Length remaining is %d\n", length_remaining);
 277                     // read the rest of the packet.
 278                     if (length_remaining < 0
 279                         || length_remaining > sizeof(mms->in_buffer) - 12) {
 280                         dprintf(NULL, "Incoming message len %d exceeds buffer len %d\n",
 281                             length_remaining, sizeof(mms->in_buffer) - 12);
 282                         return -1;
 283                     }
 284                     read_result = url_read_complete(mms->mms_hd, mms->in_buffer + 12,
 285                                                   length_remaining) ;
 286                     if (read_result == length_remaining) {
 287                         packet_type= AV_RL16(mms->in_buffer+36);
 288                     } else {
 289                         dprintf(NULL, "read for packet type failed%d!\n", read_result);
 290                         return -1;
 291                     }
 292                     hr = AV_RL32(mms->in_buffer + 40);
 293                     if (hr) {
 294                         dprintf(NULL, "The server side send back error code:0x%x\n", hr);
 295                         return -1;
 296                     }
 297                 } else {
 298                     dprintf(NULL, "read for length remaining failed%d!\n", read_result);
 299                     return -1;
 300                 }
 301             } else {
 302                 int length_remaining;
 303                 int packet_id_type;
 304                 int tmp;
 305
 306                 // note we cache the first 8 bytes,
 307                 // then fill up the buffer with the others
 308                 tmp                       = AV_RL16(mms->in_buffer + 6);
 309                 length_remaining          = (tmp - 8) & 0xffff;
 310                 mms->incoming_packet_seq  = AV_RL32(mms->in_buffer);
 311                 packet_id_type            = mms->in_buffer[4];
 312                 mms->incoming_flags       = mms->in_buffer[5];
 313
 314                 if (length_remaining < 0
 315                         || length_remaining > sizeof(mms->in_buffer) - 8) {
 316                     dprintf(NULL, "Incoming data len %d exceeds buffer len %d\n",
 317                             length_remaining, sizeof(mms->in_buffer));
 318                     return -1;
 319                 }
 320                 mms->remaining_in_len    = length_remaining;
 321                 mms->read_in_ptr         = mms->in_buffer;
 322                 read_result= url_read_complete(mms->mms_hd, mms->in_buffer, length_remaining);
 323                 if(read_result != length_remaining) {
 324                     dprintf(NULL, "read_bytes result: %d asking for %d\n",
 325                             read_result, length_remaining);
 326                     return -1;
 327                 } else {
 328                     // if we successfully read everything.
 329                     if(packet_id_type == mms->header_packet_id) {
 330                         packet_type = SC_PKT_ASF_HEADER;
 331                         // Store the asf header
 332                         if(!mms->header_parsed) {
 333                             void *p = av_realloc(mms->asf_header,
 334                                               mms->asf_header_size
 335                                               + mms->remaining_in_len);
 336                             if (!p) {
 337                                 av_freep(&mms->asf_header);
 338                                 return AVERROR(ENOMEM);
 339                             }
 340                             mms->asf_header = p;
 341                             memcpy(mms->asf_header + mms->asf_header_size,
 342                                                  mms->read_in_ptr,
 343                                                  mms->remaining_in_len);
 344                             mms->asf_header_size += mms->remaining_in_len;
 345                         }
 346                         // 0x04 means asf header is sent in multiple packets.
 347                         if (mms->incoming_flags == 0x04)
 348                             continue;
 349                     } else if(packet_id_type == mms->packet_id) {
 350                         packet_type = SC_PKT_ASF_MEDIA;
 351                     } else {
 352                         dprintf(NULL, "packet id type %d is old.", packet_id_type);
 353                         continue;
 354                     }
 355                 }
 356             }
 357
 358             // preprocess some packet type
 359             if(packet_type == SC_PKT_KEEPALIVE) {
 360                 send_keepalive_packet(mms);
 361                 continue;
 362             } else if(packet_type == SC_PKT_STREAM_CHANGING) {
 363                 handle_packet_stream_changing_type(mms);
 364             } else if(packet_type == SC_PKT_ASF_MEDIA) {
 365                 pad_media_packet(mms);
 366             }
 367             return packet_type;
 368         } else {
 369             if(read_result<0) {
 370                 dprintf(NULL, "Read error (or cancelled) returned %d!\n", read_result);
 371                 packet_type = SC_PKT_CANCEL;
 372             } else {
 373                 dprintf(NULL, "Read result of zero?!\n");
 374                 packet_type = SC_PKT_NO_DATA;
 375             }
 376             return packet_type;
 377         }
 378     }
 379 }
 380
 381 static int mms_safe_send_recv(MMSContext *mms,
 382                               int (*send_fun)(MMSContext *mms),
 383                               const MMSSCPacketType expect_type)
 384 {
 385     MMSSCPacketType type;
 386     if(send_fun) {
 387         int ret = send_fun(mms);
 388         if (ret < 0) {
 389             dprintf(NULL, "Send Packet error before expecting recv packet %d\n", expect_type);
 390             return ret;
 391         }
 392     }
 393
 394     if ((type = get_tcp_server_response(mms)) != expect_type) {
 395         dprintf(NULL,"Unexpected packet type %d with type %d\n", type, expect_type);
 396         return -1;
 397     } else {
 398         return 0;
 399     }
 400 }
 401
 402 static int send_media_header_request(MMSContext *mms)
 403 {
 404     start_command_packet(mms, CS_PKT_MEDIA_HEADER_REQUEST);
 405     insert_command_prefixes(mms, 1, 0);
 406     bytestream_put_le32(&mms->write_out_ptr, 0);
 407     bytestream_put_le32(&mms->write_out_ptr, 0x00800000);
 408     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff);
 409     bytestream_put_le32(&mms->write_out_ptr, 0);
 410     bytestream_put_le32(&mms->write_out_ptr, 0);
 411     bytestream_put_le32(&mms->write_out_ptr, 0);
 412
 413     // the media preroll value in milliseconds?
 414     bytestream_put_le32(&mms->write_out_ptr, 0);
 415     bytestream_put_le32(&mms->write_out_ptr, 0x40AC2000);
 416     bytestream_put_le32(&mms->write_out_ptr, 2);
 417     bytestream_put_le32(&mms->write_out_ptr, 0);
 418
 419     return send_command_packet(mms);
 420 }
 421
 422 /** Send the initial handshake. */
 423 static int send_startup_packet(MMSContext *mms)
 424 {
 425     char data_string[256];
 426     // SubscriberName is defined in MS specification linked below.
 427     // The guid value can be any valid value.
 428     // http://download.microsoft.com/
 429     // download/9/5/E/95EF66AF-9026-4BB0-A41D-A4F81802D92C/%5BMS-WMSP%5D.pdf
 430     snprintf(data_string, sizeof(data_string),
 431             "NSPlayer/7.0.0.1956; {%s}; Host: %s",
 432             "7E667F5D-A661-495E-A512-F55686DDA178", mms->host);
 433
 434     start_command_packet(mms, CS_PKT_INITIAL);
 435     insert_command_prefixes(mms, 0, 0x0004000b);
 436     bytestream_put_le32(&mms->write_out_ptr, 0x0003001c);
 437     mms_put_utf16(mms, data_string);
 438     return send_command_packet(mms);
 439 }
 440
 441 static int asf_header_parser(MMSContext *mms)
 442 {
 443     uint8_t *p = mms->asf_header;
 444     uint8_t *end;
 445     int flags, stream_id;
 446     mms->stream_num = 0;
 447
 448     if (mms->asf_header_size < sizeof(ff_asf_guid) * 2 + 22 ||
 449         memcmp(p, ff_asf_header, sizeof(ff_asf_guid)))
 450         return -1;
 451
 452     end = mms->asf_header + mms->asf_header_size;
 453
 454     p += sizeof(ff_asf_guid) + 14;
 455     while(end - p >= sizeof(ff_asf_guid) + 8) {
 456         uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid));
 457         if (!chunksize || chunksize > end - p) {
 458             dprintf(NULL, "chunksize is exceptional value:%"PRId64"!\n", chunksize);
 459             return -1;
 460         }
 461         if (!memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) {
 462             /* read packet size */
 463             if (end - p > sizeof(ff_asf_guid) * 2 + 68) {
 464                 mms->asf_packet_len = AV_RL32(p + sizeof(ff_asf_guid) * 2 + 64);
 465                 if (mms->asf_packet_len <= 0 || mms->asf_packet_len > sizeof(mms->in_buffer)) {
 466                     dprintf(NULL,"Too large packet len:%d"
 467                         " may overwrite in_buffer when padding", mms->asf_packet_len);
 468                     return -1;
 469                 }
 470             }
 471         } else if (!memcmp(p, ff_asf_stream_header, sizeof(ff_asf_guid))) {
 472             flags     = AV_RL16(p + sizeof(ff_asf_guid)*3 + 24);
 473             stream_id = flags & 0x7F;
 474             //The second condition is for checking CS_PKT_STREAM_ID_REQUEST packet size,
 475             //we can calcuate the packet size by stream_num.
 476             //Please see function send_stream_selection_request().
 477             if (mms->stream_num < MAX_STREAMS &&
 478                     46 + mms->stream_num * 6 < sizeof(mms->out_buffer)) {
 479                 mms->streams[mms->stream_num].id = stream_id;
 480                 mms->stream_num++;
 481             } else {
 482                 dprintf(NULL, "Too many streams.\n");
 483                 return -1;
 484             }
 485         } else if (!memcmp(p, ff_asf_head1_guid, sizeof(ff_asf_guid))) {
 486             chunksize = 46; // see references [2] section 3.4. This should be set 46.
 487         }
 488         p += chunksize;
 489     }
 490
 491     return 0;
 492 }
 493
 494 /** Send MMST stream selection command based on the AVStream->discard values. */
 495 static int send_stream_selection_request(MMSContext *mms)
 496 {
 497     int i;
 498
 499     //  send the streams we want back...
 500     start_command_packet(mms, CS_PKT_STREAM_ID_REQUEST);
 501     bytestream_put_le32(&mms->write_out_ptr, mms->stream_num);         // stream nums
 502     for(i= 0; i<mms->stream_num; i++) {
 503         bytestream_put_le16(&mms->write_out_ptr, 0xffff);              // flags
 504         bytestream_put_le16(&mms->write_out_ptr, mms->streams[i].id);  // stream id
 505         bytestream_put_le16(&mms->write_out_ptr, 0);                   // selection
 506     }
 507     return send_command_packet(mms);
 508 }
 509
 510 static int read_data(MMSContext *mms, uint8_t *buf, const int buf_size)
 511 {
 512     int read_size;
 513     read_size = FFMIN(buf_size, mms->remaining_in_len);
 514     memcpy(buf, mms->read_in_ptr, read_size);
 515     mms->remaining_in_len -= read_size;
 516     mms->read_in_ptr      += read_size;
 517     return read_size;
 518 }
 519
 520 /** Read at most one media packet (or a whole header). */
 521 static int read_mms_packet(MMSContext *mms, uint8_t *buf, int buf_size)
 522 {
 523     int result = 0;
 524     int size_to_copy;
 525
 526     do {
 527         if(mms->asf_header_read_size < mms->asf_header_size && !mms->is_playing) {
 528             /* Read from ASF header buffer */
 529             size_to_copy= FFMIN(buf_size,
 530                                 mms->asf_header_size - mms->asf_header_read_size);
 531             memcpy(buf, mms->asf_header + mms->asf_header_read_size, size_to_copy);
 532             mms->asf_header_read_size += size_to_copy;
 533             result += size_to_copy;
 534             dprintf(NULL, "Copied %d bytes from stored header. left: %d\n",
 535                    size_to_copy, mms->asf_header_size - mms->asf_header_read_size);
 536             if (mms->asf_header_size == mms->asf_header_read_size) {
 537                 av_freep(&mms->asf_header);
 538                 mms->is_playing = 1;
 539             }
 540         } else if(mms->remaining_in_len) {
 541             /* Read remaining packet data to buffer.
 542              * the result can not be zero because remaining_in_len is positive.*/
 543             result = read_data(mms, buf, buf_size);
 544         } else {
 545             /* Read from network */
 546             int err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_MEDIA);
 547             if (err == 0) {
 548                 if(mms->remaining_in_len>mms->asf_packet_len) {
 549                     dprintf(NULL, "Incoming packet"
 550                             "larger than the asf packet size stated (%d>%d)\n",
 551                             mms->remaining_in_len, mms->asf_packet_len);
 552                     result= AVERROR_IO;
 553                 } else {
 554                     // copy the data to the packet buffer.
 555                     result = read_data(mms, buf, buf_size);
 556                     if (result == 0) {
 557                         dprintf(NULL, "read asf media paket size is zero!\n");
 558                         break;
 559                     }
 560                 }
 561             } else {
 562                 dprintf(NULL, "read packet error!\n");
 563                 break;
 564             }
 565         }
 566     } while(!result); // only return one packet.
 567     return result;
 568 }
 569
 570 static int send_close_packet(MMSContext *mms)
 571 {
 572     start_command_packet(mms, CS_PKT_STREAM_CLOSE);
 573     insert_command_prefixes(mms, 1, 1);
 574
 575     return send_command_packet(mms);
 576 }
 577
 578 /** Close the MMSH/MMST connection */
 579 static int mms_close(URLContext *h)
 580 {
 581     MMSContext *mms = (MMSContext *)h->priv_data;
 582
 583     if(mms->mms_hd) {
 584         send_close_packet(mms);
 585         url_close(mms->mms_hd);
 586     }
 587
 588     /* free all separately allocated pointers in mms */
 589     av_free(mms->asf_header);
 590     av_freep(&h->priv_data);
 591
 592     return 0;
 593 }
 594
 595 static int mms_open(URLContext *h, const char *uri, int flags)
 596 {
 597     MMSContext *mms;
 598     int port, err;
 599     char tcpname[256];
 600
 601     h->is_streamed = 1;
 602     mms = h->priv_data = av_mallocz(sizeof(MMSContext));
 603     if (!h->priv_data)
 604         return AVERROR(ENOMEM);
 605
 606     // only for MMS over TCP, so set proto = NULL
 607     av_url_split(NULL, 0, NULL, 0,
 608             mms->host, sizeof(mms->host), &port, mms->path,
 609             sizeof(mms->path), uri);
 610
 611     if(port<0)
 612         port = 1755; // defaut mms protocol port
 613
 614     // establish tcp connection.
 615     ff_url_join(tcpname, sizeof(tcpname), "tcp", NULL, mms->host, port, NULL);
 616     err = url_open(&mms->mms_hd, tcpname, URL_RDWR);
 617     if (err)
 618         goto fail;
 619
 620     mms->packet_id        = 3;          // default, initial value.
 621     mms->header_packet_id = 2;          // default, initial value.
 622     err = mms_safe_send_recv(mms, send_startup_packet, SC_PKT_CLIENT_ACCEPTED);
 623     if (err)
 624         goto fail;
 625     err = mms_safe_send_recv(mms, send_time_test_data, SC_PKT_TIMING_TEST_REPLY);
 626     if (err)
 627         goto fail;
 628     err = mms_safe_send_recv(mms, send_protocol_select, SC_PKT_PROTOCOL_ACCEPTED);
 629     if (err)
 630         goto fail;
 631     err = mms_safe_send_recv(mms, send_media_file_request, SC_PKT_MEDIA_FILE_DETAILS);
 632     if (err)
 633         goto fail;
 634     err = mms_safe_send_recv(mms, send_media_header_request, SC_PKT_HEADER_REQUEST_ACCEPTED);
 635     if (err)
 636         goto fail;
 637     err = mms_safe_send_recv(mms, NULL, SC_PKT_ASF_HEADER);
 638     if (err)
 639         goto fail;
 640     if((mms->incoming_flags != 0X08) && (mms->incoming_flags != 0X0C))
 641         goto fail;
 642     err = asf_header_parser(mms);
 643     if (err) {
 644         dprintf(NULL, "asf header parsed failed!\n");
 645         goto fail;
 646     }
 647     mms->header_parsed = 1;
 648
 649     if (!mms->asf_packet_len || !mms->stream_num)
 650         goto fail;
 651
 652     dprintf(NULL, "Leaving open (success)\n");
 653     return 0;
 654 fail:
 655     mms_close(h);
 656     dprintf(NULL, "Leaving open (failure: %d)\n", err);
 657     return err;
 658 }
 659
 660 static int send_media_packet_request(MMSContext *mms)
 661 {
 662     start_command_packet(mms, CS_PKT_START_FROM_PKT_ID);
 663     insert_command_prefixes(mms, 1, 0x0001FFFF);
 664     bytestream_put_le64(&mms->write_out_ptr, 0);          // seek timestamp
 665     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // unknown
 666     bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // packet offset
 667     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
 668     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
 669     bytestream_put_byte(&mms->write_out_ptr, 0xff);       // max stream time limit
 670     bytestream_put_byte(&mms->write_out_ptr, 0x00);       // stream time limit flag
 671
 672     mms->packet_id++;                                     // new packet_id
 673     bytestream_put_le32(&mms->write_out_ptr, mms->packet_id);
 674     return send_command_packet(mms);
 675 }
 676
 677
 678 static void clear_stream_buffers(MMSContext *mms)
 679 {
 680     mms->remaining_in_len = 0;
 681     mms->read_in_ptr      = mms->in_buffer;
 682 }
 683
 684 /** Read ASF data through the protocol. */
 685 static int mms_read(URLContext *h, uint8_t *buf, int size)
 686 {
 687     /* TODO: see tcp.c:tcp_read() about a possible timeout scheme */
 688     MMSContext *mms = h->priv_data;
 689     int result = 0;
 690
 691     /* Since we read the header at open(), this shouldn't be possible */
 692     assert(mms->header_parsed);
 693
 694     if (!mms->is_playing) {
 695         dprintf(NULL, "mms_read() before play().\n");
 696         clear_stream_buffers(mms);
 697         result = mms_safe_send_recv(mms, send_stream_selection_request, SC_PKT_STREAM_ID_ACCEPTED);
 698         if (result)
 699             return result;
 700         // send media packet request
 701         result = mms_safe_send_recv(mms, send_media_packet_request, SC_PKT_MEDIA_PKT_FOLLOWS);
 702         if (result) {
 703             return result;
 704         }
 705     }
 706     return read_mms_packet(mms, buf, size);
 707 }
 708
 709 URLProtocol mmst_protocol = {
 710     "mmst",
 711     mms_open,
 712     mms_read,
 713     NULL, // write
 714     NULL, // seek
 715     mms_close,
 716 };