1 /*
2  * MMS protocol over HTTP
3  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /*
23  * Reference
24  * Windows Media HTTP Streaming Protocol.
25  * http://msdn.microsoft.com/en-us/library/cc251059(PROT.10).aspx
26  */
27 
28 #include <string.h>
29 #include "libavutil/intreadwrite.h"
30 #include "libavutil/avstring.h"
31 #include "libavutil/opt.h"
32 #include "internal.h"
33 #include "mms.h"
34 #include "http.h"
35 #include "url.h"
36 
37 #define CHUNK_HEADER_LENGTH 4   // 2bytes chunk type and 2bytes chunk length.
38 #define EXT_HEADER_LENGTH   8   // 4bytes sequence, 2bytes useless and 2bytes chunk length.
39 
40 // see Ref 2.2.1.8
41 #define USERAGENT  "User-Agent: NSPlayer/4.1.0.3856\r\n"
42 // see Ref 2.2.1.4.33
43 // the GUID value can be changed to any valid value.
44 #define CLIENTGUID "Pragma: xClientGUID={c77e7400-738a-11d2-9add-0020af0a3278}\r\n"
45 
46 // see Ref 2.2.3 for packet type define:
47 // chunk type contains 2 fields: Frame and PacketID.
48 // Frame is 0x24 or 0xA4(rarely), different PacketID indicates different packet type.
49 typedef enum {
50     CHUNK_TYPE_DATA          = 0x4424,
51     CHUNK_TYPE_ASF_HEADER    = 0x4824,
52     CHUNK_TYPE_END           = 0x4524,
53     CHUNK_TYPE_STREAM_CHANGE = 0x4324,
54 } ChunkType;
55 
56 typedef struct MMSHContext {
57     MMSContext mms;
58     uint8_t location[1024];
59     int request_seq;  ///< request packet sequence
60     int chunk_seq;    ///< data packet sequence
61 } MMSHContext;
62 
mmsh_close(URLContext *h)63 static int mmsh_close(URLContext *h)
64 {
65     MMSHContext *mmsh = (MMSHContext *)h->priv_data;
66     MMSContext *mms   = &mmsh->mms;
67     ffurl_closep(&mms->mms_hd);
68     av_freep(&mms->streams);
69     av_freep(&mms->asf_header);
70     return 0;
71 }
72 
get_chunk_header(MMSHContext *mmsh, int *len)73 static ChunkType get_chunk_header(MMSHContext *mmsh, int *len)
74 {
75     MMSContext *mms = &mmsh->mms;
76     uint8_t chunk_header[CHUNK_HEADER_LENGTH];
77     uint8_t ext_header[EXT_HEADER_LENGTH];
78     ChunkType chunk_type;
79     int chunk_len, res, ext_header_len;
80 
81     res = ffurl_read_complete(mms->mms_hd, chunk_header, CHUNK_HEADER_LENGTH);
82     if (res != CHUNK_HEADER_LENGTH) {
83         av_log(NULL, AV_LOG_ERROR, "Read data packet header failed!\n");
84         return AVERROR(EIO);
85     }
86     chunk_type = AV_RL16(chunk_header);
87     chunk_len  = AV_RL16(chunk_header + 2);
88 
89     switch (chunk_type) {
90     case CHUNK_TYPE_END:
91     case CHUNK_TYPE_STREAM_CHANGE:
92         ext_header_len = 4;
93         break;
94     case CHUNK_TYPE_ASF_HEADER:
95     case CHUNK_TYPE_DATA:
96         ext_header_len = 8;
97         break;
98     default:
99         av_log(NULL, AV_LOG_ERROR, "Strange chunk type %d\n", chunk_type);
100         return AVERROR_INVALIDDATA;
101     }
102 
103     res = ffurl_read_complete(mms->mms_hd, ext_header, ext_header_len);
104     if (res != ext_header_len) {
105         av_log(NULL, AV_LOG_ERROR, "Read ext header failed!\n");
106         return AVERROR(EIO);
107     }
108     *len = chunk_len - ext_header_len;
109     if (chunk_type == CHUNK_TYPE_END || chunk_type == CHUNK_TYPE_DATA)
110         mmsh->chunk_seq = AV_RL32(ext_header);
111     return chunk_type;
112 }
113 
read_data_packet(MMSHContext *mmsh, const int len)114 static int read_data_packet(MMSHContext *mmsh, const int len)
115 {
116     MMSContext *mms   = &mmsh->mms;
117     int res;
118     if (len > sizeof(mms->in_buffer)) {
119         av_log(NULL, AV_LOG_ERROR,
120                "Data packet length %d exceeds the in_buffer size %"SIZE_SPECIFIER"\n",
121                len, sizeof(mms->in_buffer));
122         return AVERROR(EIO);
123     }
124     res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len);
125     av_log(NULL, AV_LOG_TRACE, "Data packet len = %d\n", len);
126     if (res != len) {
127         av_log(NULL, AV_LOG_ERROR, "Read data packet failed!\n");
128         return AVERROR(EIO);
129     }
130     if (len > mms->asf_packet_len) {
131         av_log(NULL, AV_LOG_ERROR,
132                "Chunk length %d exceed packet length %d\n",len, mms->asf_packet_len);
133         return AVERROR_INVALIDDATA;
134     } else {
135         memset(mms->in_buffer + len, 0, mms->asf_packet_len - len); // padding
136     }
137     mms->read_in_ptr      = mms->in_buffer;
138     mms->remaining_in_len = mms->asf_packet_len;
139     return 0;
140 }
141 
get_http_header_data(MMSHContext *mmsh)142 static int get_http_header_data(MMSHContext *mmsh)
143 {
144     MMSContext *mms = &mmsh->mms;
145     int res, len;
146     ChunkType chunk_type;
147 
148     for (;;) {
149         len = 0;
150         res = chunk_type = get_chunk_header(mmsh, &len);
151         if (res < 0) {
152             return res;
153         } else if (chunk_type == CHUNK_TYPE_ASF_HEADER){
154             // get asf header and stored it
155             if (!mms->header_parsed) {
156                 if (mms->asf_header) {
157                     if (len != mms->asf_header_size) {
158                         mms->asf_header_size = len;
159                         av_log(NULL, AV_LOG_TRACE, "Header len changed from %d to %d\n",
160                                 mms->asf_header_size, len);
161                         av_freep(&mms->asf_header);
162                     }
163                 }
164                 mms->asf_header = av_mallocz(len);
165                 if (!mms->asf_header) {
166                     return AVERROR(ENOMEM);
167                 }
168                 mms->asf_header_size = len;
169             }
170             if (len > mms->asf_header_size) {
171                 av_log(NULL, AV_LOG_ERROR,
172                        "Asf header packet len = %d exceed the asf header buf size %d\n",
173                        len, mms->asf_header_size);
174                 return AVERROR(EIO);
175             }
176             res = ffurl_read_complete(mms->mms_hd, mms->asf_header, len);
177             if (res != len) {
178                 av_log(NULL, AV_LOG_ERROR,
179                        "Recv asf header data len %d != expected len %d\n", res, len);
180                 return AVERROR(EIO);
181             }
182             mms->asf_header_size = len;
183             if (!mms->header_parsed) {
184                 res = ff_mms_asf_header_parser(mms);
185                 mms->header_parsed = 1;
186                 return res;
187             }
188         } else if (chunk_type == CHUNK_TYPE_DATA) {
189             // read data packet and do padding
190             return read_data_packet(mmsh, len);
191         } else {
192             if (len) {
193                 if (len > sizeof(mms->in_buffer)) {
194                     av_log(NULL, AV_LOG_ERROR,
195                            "Other packet len = %d exceed the in_buffer size %"SIZE_SPECIFIER"\n",
196                            len, sizeof(mms->in_buffer));
197                     return AVERROR(EIO);
198                 }
199                 res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len);
200                 if (res != len) {
201                     av_log(NULL, AV_LOG_ERROR, "Read other chunk type data failed!\n");
202                     return AVERROR(EIO);
203                 } else {
204                     av_log(NULL, AV_LOG_TRACE, "Skip chunk type %d \n", chunk_type);
205                     continue;
206                 }
207             }
208         }
209     }
210 }
211 
mmsh_open_internal(URLContext *h, const char *uri, int flags, int timestamp, int64_t pos)212 static int mmsh_open_internal(URLContext *h, const char *uri, int flags, int timestamp, int64_t pos)
213 {
214     int i, port, err;
215     char httpname[256], path[256], host[128];
216     char *stream_selection = NULL;
217     char headers[1024];
218     MMSHContext *mmsh = h->priv_data;
219     MMSContext *mms;
220 
221     mmsh->request_seq = h->is_streamed = 1;
222     mms = &mmsh->mms;
223     av_strlcpy(mmsh->location, uri, sizeof(mmsh->location));
224 
225     av_url_split(NULL, 0, NULL, 0,
226         host, sizeof(host), &port, path, sizeof(path), mmsh->location);
227     if (port<0)
228         port = 80; // default mmsh protocol port
229     ff_url_join(httpname, sizeof(httpname), "http", NULL, host, port, "%s", path);
230 
231     if (ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ,
232                     &h->interrupt_callback) < 0) {
233         return AVERROR(EIO);
234     }
235 
236     snprintf(headers, sizeof(headers),
237              "Accept: */*\r\n"
238              USERAGENT
239              "Host: %s:%d\r\n"
240              "Pragma: no-cache,rate=1.000000,stream-time=0,"
241              "stream-offset=0:0,request-context=%u,max-duration=0\r\n"
242              CLIENTGUID
243              "Connection: Close\r\n",
244              host, port, mmsh->request_seq++);
245     av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0);
246 
247     if (!mms->mms_hd->protocol_whitelist && h->protocol_whitelist) {
248         mms->mms_hd->protocol_whitelist = av_strdup(h->protocol_whitelist);
249         if (!mms->mms_hd->protocol_whitelist) {
250             err = AVERROR(ENOMEM);
251             goto fail;
252         }
253     }
254 
255     err = ffurl_connect(mms->mms_hd, NULL);
256     if (err) {
257         goto fail;
258     }
259     err = get_http_header_data(mmsh);
260     if (err) {
261         av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n");
262         goto fail;
263     }
264 
265     // close the socket and then reopen it for sending the second play request.
266     ffurl_closep(&mms->mms_hd);
267     memset(headers, 0, sizeof(headers));
268     if ((err = ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ,
269                            &h->interrupt_callback)) < 0) {
270         goto fail;
271     }
272     stream_selection = av_mallocz(mms->stream_num * 19 + 1);
273     if (!stream_selection)
274         return AVERROR(ENOMEM);
275     for (i = 0; i < mms->stream_num; i++) {
276         char tmp[20];
277         err = snprintf(tmp, sizeof(tmp), "ffff:%d:0 ", mms->streams[i].id);
278         if (err < 0)
279             goto fail;
280         av_strlcat(stream_selection, tmp, mms->stream_num * 19 + 1);
281     }
282     // send play request
283     err = snprintf(headers, sizeof(headers),
284                    "Accept: */*\r\n"
285                    USERAGENT
286                    "Host: %s:%d\r\n"
287                    "Pragma: no-cache,rate=1.000000,request-context=%u\r\n"
288                    "Pragma: xPlayStrm=1\r\n"
289                    CLIENTGUID
290                    "Pragma: stream-switch-count=%d\r\n"
291                    "Pragma: stream-switch-entry=%s\r\n"
292                    "Pragma: no-cache,rate=1.000000,stream-time=%u"
293                    "Connection: Close\r\n",
294                    host, port, mmsh->request_seq++, mms->stream_num, stream_selection, timestamp);
295     av_freep(&stream_selection);
296     if (err < 0) {
297         av_log(NULL, AV_LOG_ERROR, "Build play request failed!\n");
298         goto fail;
299     }
300     av_log(NULL, AV_LOG_TRACE, "out_buffer is %s", headers);
301     av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0);
302 
303     err = ffurl_connect(mms->mms_hd, NULL);
304     if (err) {
305           goto fail;
306     }
307 
308     err = get_http_header_data(mmsh);
309     if (err) {
310         av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n");
311         goto fail;
312     }
313 
314     av_log(NULL, AV_LOG_TRACE, "Connection successfully open\n");
315     return 0;
316 fail:
317     av_freep(&stream_selection);
318     mmsh_close(h);
319     av_log(NULL, AV_LOG_TRACE, "Connection failed with error %d\n", err);
320     return err;
321 }
322 
mmsh_open(URLContext *h, const char *uri, int flags)323 static int mmsh_open(URLContext *h, const char *uri, int flags)
324 {
325     return mmsh_open_internal(h, uri, flags, 0, 0);
326 }
327 
handle_chunk_type(MMSHContext *mmsh)328 static int handle_chunk_type(MMSHContext *mmsh)
329 {
330     MMSContext *mms = &mmsh->mms;
331     int res, len = 0;
332     ChunkType chunk_type;
333     chunk_type = get_chunk_header(mmsh, &len);
334 
335     switch (chunk_type) {
336     case CHUNK_TYPE_END:
337         mmsh->chunk_seq = 0;
338         av_log(NULL, AV_LOG_ERROR, "Stream ended!\n");
339         return AVERROR(EIO);
340     case CHUNK_TYPE_STREAM_CHANGE:
341         mms->header_parsed = 0;
342         if (res = get_http_header_data(mmsh)) {
343             av_log(NULL, AV_LOG_ERROR,"Stream changed! Failed to get new header!\n");
344             return res;
345         }
346         break;
347     case CHUNK_TYPE_DATA:
348         return read_data_packet(mmsh, len);
349     default:
350         av_log(NULL, AV_LOG_ERROR, "Recv other type packet %d\n", chunk_type);
351         return AVERROR_INVALIDDATA;
352     }
353     return 0;
354 }
355 
mmsh_read(URLContext *h, uint8_t *buf, int size)356 static int mmsh_read(URLContext *h, uint8_t *buf, int size)
357 {
358     int res = 0;
359     MMSHContext *mmsh = h->priv_data;
360     MMSContext *mms   = &mmsh->mms;
361     do {
362         if (mms->asf_header_read_size < mms->asf_header_size) {
363             // copy asf header into buffer
364             res = ff_mms_read_header(mms, buf, size);
365         } else {
366             if (!mms->remaining_in_len && (res = handle_chunk_type(mmsh)))
367                 return res;
368             res = ff_mms_read_data(mms, buf, size);
369         }
370     } while (!res);
371     return res;
372 }
373 
mmsh_read_seek(URLContext *h, int stream_index, int64_t timestamp, int flags)374 static int64_t mmsh_read_seek(URLContext *h, int stream_index,
375                         int64_t timestamp, int flags)
376 {
377     MMSHContext *mmsh_old = h->priv_data;
378     MMSHContext *mmsh     = av_mallocz(sizeof(*mmsh));
379     int ret;
380 
381     if (!mmsh)
382         return AVERROR(ENOMEM);
383 
384     h->priv_data = mmsh;
385     ret= mmsh_open_internal(h, mmsh_old->location, 0, FFMAX(timestamp, 0), 0);
386     if(ret>=0){
387         h->priv_data = mmsh_old;
388         mmsh_close(h);
389         h->priv_data = mmsh;
390         av_free(mmsh_old);
391         mmsh->mms.asf_header_read_size = mmsh->mms.asf_header_size;
392     }else {
393         h->priv_data = mmsh_old;
394         av_free(mmsh);
395     }
396 
397     return ret;
398 }
399 
mmsh_seek(URLContext *h, int64_t pos, int whence)400 static int64_t mmsh_seek(URLContext *h, int64_t pos, int whence)
401 {
402     MMSHContext *mmsh = h->priv_data;
403     MMSContext *mms   = &mmsh->mms;
404 
405     if(pos == 0 && whence == SEEK_CUR)
406         return mms->asf_header_read_size + mms->remaining_in_len + mmsh->chunk_seq * (int64_t)mms->asf_packet_len;
407     return AVERROR(ENOSYS);
408 }
409 
410 const URLProtocol ff_mmsh_protocol = {
411     .name           = "mmsh",
412     .url_open       = mmsh_open,
413     .url_read       = mmsh_read,
414     .url_seek       = mmsh_seek,
415     .url_close      = mmsh_close,
416     .url_read_seek  = mmsh_read_seek,
417     .priv_data_size = sizeof(MMSHContext),
418     .flags          = URL_PROTOCOL_FLAG_NETWORK,
419     .default_whitelist = "http,tcp",
420 };
421