libavformat/mmsh.c
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00001 /*
00002  * MMS protocol over HTTP
00003  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 /*
00023  * Reference
00024  * Windows Media HTTP Streaming Protocol.
00025  * http://msdn.microsoft.com/en-us/library/cc251059(PROT.10).aspx
00026  */
00027 
00028 #include <string.h>
00029 #include "libavutil/intreadwrite.h"
00030 #include "libavutil/avstring.h"
00031 #include "libavutil/opt.h"
00032 #include "internal.h"
00033 #include "mms.h"
00034 #include "asf.h"
00035 #include "http.h"
00036 #include "url.h"
00037 
00038 #define CHUNK_HEADER_LENGTH 4   // 2bytes chunk type and 2bytes chunk length.
00039 #define EXT_HEADER_LENGTH   8   // 4bytes sequence, 2bytes useless and 2bytes chunk length.
00040 
00041 // see Ref 2.2.1.8
00042 #define USERAGENT  "User-Agent: NSPlayer/4.1.0.3856\r\n"
00043 // see Ref 2.2.1.4.33
00044 // the guid value can be changed to any valid value.
00045 #define CLIENTGUID "Pragma: xClientGUID={c77e7400-738a-11d2-9add-0020af0a3278}\r\n"
00046 
00047 // see Ref 2.2.3 for packet type define:
00048 // chunk type contains 2 fields: Frame and PacketID.
00049 // Frame is 0x24 or 0xA4(rarely), different PacketID indicates different packet type.
00050 typedef enum {
00051     CHUNK_TYPE_DATA          = 0x4424,
00052     CHUNK_TYPE_ASF_HEADER    = 0x4824,
00053     CHUNK_TYPE_END           = 0x4524,
00054     CHUNK_TYPE_STREAM_CHANGE = 0x4324,
00055 } ChunkType;
00056 
00057 typedef struct {
00058     MMSContext mms;
00059     uint8_t location[1024];
00060     int request_seq;  
00061     int chunk_seq;    
00062 } MMSHContext;
00063 
00064 static int mmsh_close(URLContext *h)
00065 {
00066     MMSHContext *mmsh = (MMSHContext *)h->priv_data;
00067     MMSContext *mms   = &mmsh->mms;
00068     if (mms->mms_hd)
00069         ffurl_close(mms->mms_hd);
00070     av_free(mms->streams);
00071     av_free(mms->asf_header);
00072     return 0;
00073 }
00074 
00075 static ChunkType get_chunk_header(MMSHContext *mmsh, int *len)
00076 {
00077     MMSContext *mms = &mmsh->mms;
00078     uint8_t chunk_header[CHUNK_HEADER_LENGTH];
00079     uint8_t ext_header[EXT_HEADER_LENGTH];
00080     ChunkType chunk_type;
00081     int chunk_len, res, ext_header_len;
00082 
00083     res = ffurl_read_complete(mms->mms_hd, chunk_header, CHUNK_HEADER_LENGTH);
00084     if (res != CHUNK_HEADER_LENGTH) {
00085         av_log(NULL, AV_LOG_ERROR, "Read data packet header failed!\n");
00086         return AVERROR(EIO);
00087     }
00088     chunk_type = AV_RL16(chunk_header);
00089     chunk_len  = AV_RL16(chunk_header + 2);
00090 
00091     switch (chunk_type) {
00092     case CHUNK_TYPE_END:
00093     case CHUNK_TYPE_STREAM_CHANGE:
00094         ext_header_len = 4;
00095         break;
00096     case CHUNK_TYPE_ASF_HEADER:
00097     case CHUNK_TYPE_DATA:
00098         ext_header_len = 8;
00099         break;
00100     default:
00101         av_log(NULL, AV_LOG_ERROR, "Strange chunk type %d\n", chunk_type);
00102         return AVERROR_INVALIDDATA;
00103     }
00104 
00105     res = ffurl_read_complete(mms->mms_hd, ext_header, ext_header_len);
00106     if (res != ext_header_len) {
00107         av_log(NULL, AV_LOG_ERROR, "Read ext header failed!\n");
00108         return AVERROR(EIO);
00109     }
00110     *len = chunk_len - ext_header_len;
00111     if (chunk_type == CHUNK_TYPE_END || chunk_type == CHUNK_TYPE_DATA)
00112         mmsh->chunk_seq = AV_RL32(ext_header);
00113     return chunk_type;
00114 }
00115 
00116 static int read_data_packet(MMSHContext *mmsh, const int len)
00117 {
00118     MMSContext *mms   = &mmsh->mms;
00119     int res;
00120     if (len > sizeof(mms->in_buffer)) {
00121         av_log(NULL, AV_LOG_ERROR,
00122                "Data packet length %d exceeds the in_buffer size %zu\n",
00123                len, sizeof(mms->in_buffer));
00124         return AVERROR(EIO);
00125     }
00126     res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len);
00127     av_dlog(NULL, "Data packet len = %d\n", len);
00128     if (res != len) {
00129         av_log(NULL, AV_LOG_ERROR, "Read data packet failed!\n");
00130         return AVERROR(EIO);
00131     }
00132     if (len > mms->asf_packet_len) {
00133         av_log(NULL, AV_LOG_ERROR,
00134                "Chunk length %d exceed packet length %d\n",len, mms->asf_packet_len);
00135         return AVERROR_INVALIDDATA;
00136     } else {
00137         memset(mms->in_buffer + len, 0, mms->asf_packet_len - len); // padding
00138     }
00139     mms->read_in_ptr      = mms->in_buffer;
00140     mms->remaining_in_len = mms->asf_packet_len;
00141     return 0;
00142 }
00143 
00144 static int get_http_header_data(MMSHContext *mmsh)
00145 {
00146     MMSContext *mms = &mmsh->mms;
00147     int res, len;
00148     ChunkType chunk_type;
00149 
00150     for (;;) {
00151         len = 0;
00152         res = chunk_type = get_chunk_header(mmsh, &len);
00153         if (res < 0) {
00154             return res;
00155         } else if (chunk_type == CHUNK_TYPE_ASF_HEADER){
00156             // get asf header and stored it
00157             if (!mms->header_parsed) {
00158                 if (mms->asf_header) {
00159                     if (len != mms->asf_header_size) {
00160                         mms->asf_header_size = len;
00161                         av_dlog(NULL, "Header len changed from %d to %d\n",
00162                                 mms->asf_header_size, len);
00163                         av_freep(&mms->asf_header);
00164                     }
00165                 }
00166                 mms->asf_header = av_mallocz(len);
00167                 if (!mms->asf_header) {
00168                     return AVERROR(ENOMEM);
00169                 }
00170                 mms->asf_header_size = len;
00171             }
00172             if (len > mms->asf_header_size) {
00173                 av_log(NULL, AV_LOG_ERROR,
00174                        "Asf header packet len = %d exceed the asf header buf size %d\n",
00175                        len, mms->asf_header_size);
00176                 return AVERROR(EIO);
00177             }
00178             res = ffurl_read_complete(mms->mms_hd, mms->asf_header, len);
00179             if (res != len) {
00180                 av_log(NULL, AV_LOG_ERROR,
00181                        "Recv asf header data len %d != expected len %d\n", res, len);
00182                 return AVERROR(EIO);
00183             }
00184             mms->asf_header_size = len;
00185             if (!mms->header_parsed) {
00186                 res = ff_mms_asf_header_parser(mms);
00187                 mms->header_parsed = 1;
00188                 return res;
00189             }
00190         } else if (chunk_type == CHUNK_TYPE_DATA) {
00191             // read data packet and do padding
00192             return read_data_packet(mmsh, len);
00193         } else {
00194             if (len) {
00195                 if (len > sizeof(mms->in_buffer)) {
00196                     av_log(NULL, AV_LOG_ERROR,
00197                            "Other packet len = %d exceed the in_buffer size %zu\n",
00198                            len, sizeof(mms->in_buffer));
00199                     return AVERROR(EIO);
00200                 }
00201                 res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len);
00202                 if (res != len) {
00203                     av_log(NULL, AV_LOG_ERROR, "Read other chunk type data failed!\n");
00204                     return AVERROR(EIO);
00205                 } else {
00206                     av_dlog(NULL, "Skip chunk type %d \n", chunk_type);
00207                     continue;
00208                 }
00209             }
00210         }
00211     }
00212 }
00213 
00214 static int mmsh_open_internal(URLContext *h, const char *uri, int flags, int timestamp, int64_t pos)
00215 {
00216     int i, port, err;
00217     char httpname[256], path[256], host[128];
00218     char *stream_selection = NULL;
00219     char headers[1024];
00220     MMSHContext *mmsh = h->priv_data;
00221     MMSContext *mms;
00222 
00223     mmsh->request_seq = h->is_streamed = 1;
00224     mms = &mmsh->mms;
00225     av_strlcpy(mmsh->location, uri, sizeof(mmsh->location));
00226 
00227     av_url_split(NULL, 0, NULL, 0,
00228         host, sizeof(host), &port, path, sizeof(path), mmsh->location);
00229     if (port<0)
00230         port = 80; // default mmsh protocol port
00231     ff_url_join(httpname, sizeof(httpname), "http", NULL, host, port, "%s", path);
00232 
00233     if (ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ,
00234                     &h->interrupt_callback) < 0) {
00235         return AVERROR(EIO);
00236     }
00237 
00238     snprintf(headers, sizeof(headers),
00239              "Accept: */*\r\n"
00240              USERAGENT
00241              "Host: %s:%d\r\n"
00242              "Pragma: no-cache,rate=1.000000,stream-time=0,"
00243              "stream-offset=0:0,request-context=%u,max-duration=0\r\n"
00244              CLIENTGUID
00245              "Connection: Close\r\n",
00246              host, port, mmsh->request_seq++);
00247     av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0);
00248 
00249     err = ffurl_connect(mms->mms_hd, NULL);
00250     if (err) {
00251         goto fail;
00252     }
00253     err = get_http_header_data(mmsh);
00254     if (err) {
00255         av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n");
00256         goto fail;
00257     }
00258 
00259     // close the socket and then reopen it for sending the second play request.
00260     ffurl_close(mms->mms_hd);
00261     memset(headers, 0, sizeof(headers));
00262     if ((err = ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ,
00263                            &h->interrupt_callback)) < 0) {
00264         goto fail;
00265     }
00266     stream_selection = av_mallocz(mms->stream_num * 19 + 1);
00267     if (!stream_selection)
00268         return AVERROR(ENOMEM);
00269     for (i = 0; i < mms->stream_num; i++) {
00270         char tmp[20];
00271         err = snprintf(tmp, sizeof(tmp), "ffff:%d:0 ", mms->streams[i].id);
00272         if (err < 0)
00273             goto fail;
00274         av_strlcat(stream_selection, tmp, mms->stream_num * 19 + 1);
00275     }
00276     // send play request
00277     err = snprintf(headers, sizeof(headers),
00278                    "Accept: */*\r\n"
00279                    USERAGENT
00280                    "Host: %s:%d\r\n"
00281                    "Pragma: no-cache,rate=1.000000,request-context=%u\r\n"
00282                    "Pragma: xPlayStrm=1\r\n"
00283                    CLIENTGUID
00284                    "Pragma: stream-switch-count=%d\r\n"
00285                    "Pragma: stream-switch-entry=%s\r\n"
00286                    "Pragma: no-cache,rate=1.000000,stream-time=%u"
00287                    "Connection: Close\r\n",
00288                    host, port, mmsh->request_seq++, mms->stream_num, stream_selection, timestamp);
00289     av_freep(&stream_selection);
00290     if (err < 0) {
00291         av_log(NULL, AV_LOG_ERROR, "Build play request failed!\n");
00292         goto fail;
00293     }
00294     av_dlog(NULL, "out_buffer is %s", headers);
00295     av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0);
00296 
00297     err = ffurl_connect(mms->mms_hd, NULL);
00298     if (err) {
00299           goto fail;
00300     }
00301 
00302     err = get_http_header_data(mmsh);
00303     if (err) {
00304         av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n");
00305         goto fail;
00306     }
00307 
00308     av_dlog(NULL, "Connection successfully open\n");
00309     return 0;
00310 fail:
00311     av_freep(&stream_selection);
00312     mmsh_close(h);
00313     av_dlog(NULL, "Connection failed with error %d\n", err);
00314     return err;
00315 }
00316 
00317 static int mmsh_open(URLContext *h, const char *uri, int flags)
00318 {
00319     return mmsh_open_internal(h, uri, flags, 0, 0);
00320 }
00321 
00322 static int handle_chunk_type(MMSHContext *mmsh)
00323 {
00324     MMSContext *mms = &mmsh->mms;
00325     int res, len = 0;
00326     ChunkType chunk_type;
00327     chunk_type = get_chunk_header(mmsh, &len);
00328 
00329     switch (chunk_type) {
00330     case CHUNK_TYPE_END:
00331         mmsh->chunk_seq = 0;
00332         av_log(NULL, AV_LOG_ERROR, "Stream ended!\n");
00333         return AVERROR(EIO);
00334     case CHUNK_TYPE_STREAM_CHANGE:
00335         mms->header_parsed = 0;
00336         if (res = get_http_header_data(mmsh)) {
00337             av_log(NULL, AV_LOG_ERROR,"Stream changed! Failed to get new header!\n");
00338             return res;
00339         }
00340         break;
00341     case CHUNK_TYPE_DATA:
00342         return read_data_packet(mmsh, len);
00343     default:
00344         av_log(NULL, AV_LOG_ERROR, "Recv other type packet %d\n", chunk_type);
00345         return AVERROR_INVALIDDATA;
00346     }
00347     return 0;
00348 }
00349 
00350 static int mmsh_read(URLContext *h, uint8_t *buf, int size)
00351 {
00352     int res = 0;
00353     MMSHContext *mmsh = h->priv_data;
00354     MMSContext *mms   = &mmsh->mms;
00355     do {
00356         if (mms->asf_header_read_size < mms->asf_header_size) {
00357             // copy asf header into buffer
00358             res = ff_mms_read_header(mms, buf, size);
00359         } else {
00360             if (!mms->remaining_in_len && (res = handle_chunk_type(mmsh)))
00361                 return res;
00362             res = ff_mms_read_data(mms, buf, size);
00363         }
00364     } while (!res);
00365     return res;
00366 }
00367 
00368 static int64_t mmsh_read_seek(URLContext *h, int stream_index,
00369                         int64_t timestamp, int flags)
00370 {
00371     MMSHContext *mmsh = h->priv_data;
00372     MMSContext *mms   = &mmsh->mms;
00373     int ret;
00374 
00375     ret= mmsh_open_internal(h, mmsh->location, 0, FFMAX(timestamp, 0), 0);
00376 
00377     if(ret>=0){
00378         if (mms->mms_hd)
00379             ffurl_close(mms->mms_hd);
00380         av_freep(&mms->streams);
00381         av_freep(&mms->asf_header);
00382         av_free(mmsh);
00383         mmsh = h->priv_data;
00384         mms   = &mmsh->mms;
00385         mms->asf_header_read_size= mms->asf_header_size;
00386     }else
00387         h->priv_data= mmsh;
00388     return ret;
00389 }
00390 
00391 static int64_t mmsh_seek(URLContext *h, int64_t pos, int whence)
00392 {
00393     MMSHContext *mmsh = h->priv_data;
00394     MMSContext *mms   = &mmsh->mms;
00395 
00396     if(pos == 0 && whence == SEEK_CUR)
00397         return mms->asf_header_read_size + mms->remaining_in_len + mmsh->chunk_seq * mms->asf_packet_len;
00398     return AVERROR(ENOSYS);
00399 }
00400 
00401 URLProtocol ff_mmsh_protocol = {
00402     .name           = "mmsh",
00403     .url_open       = mmsh_open,
00404     .url_read       = mmsh_read,
00405     .url_seek       = mmsh_seek,
00406     .url_close      = mmsh_close,
00407     .url_read_seek  = mmsh_read_seek,
00408     .priv_data_size = sizeof(MMSHContext),
00409     .flags          = URL_PROTOCOL_FLAG_NETWORK,
00410 };