mmsh.c
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1 /*
2  * MMS protocol over HTTP
3  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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 "asf.h"
35 #include "http.h"
36 #include "url.h"
37 
38 #define CHUNK_HEADER_LENGTH 4 // 2bytes chunk type and 2bytes chunk length.
39 #define EXT_HEADER_LENGTH 8 // 4bytes sequence, 2bytes useless and 2bytes chunk length.
40 
41 // see Ref 2.2.1.8
42 #define USERAGENT "User-Agent: NSPlayer/4.1.0.3856\r\n"
43 // see Ref 2.2.1.4.33
44 // the guid value can be changed to any valid value.
45 #define CLIENTGUID "Pragma: xClientGUID={c77e7400-738a-11d2-9add-0020af0a3278}\r\n"
46 
47 // see Ref 2.2.3 for packet type define:
48 // chunk type contains 2 fields: Frame and PacketID.
49 // Frame is 0x24 or 0xA4(rarely), different PacketID indicates different packet type.
50 typedef enum {
51  CHUNK_TYPE_DATA = 0x4424,
53  CHUNK_TYPE_END = 0x4524,
55 } ChunkType;
56 
57 typedef struct {
60  int chunk_seq;
61 } MMSHContext;
62 
63 static int mmsh_close(URLContext *h)
64 {
65  MMSHContext *mmsh = (MMSHContext *)h->priv_data;
66  MMSContext *mms = &mmsh->mms;
67  if (mms->mms_hd)
68  ffurl_close(mms->mms_hd);
69  av_free(mms->streams);
70  av_free(mms->asf_header);
71  return 0;
72 }
73 
75 {
76  MMSContext *mms = &mmsh->mms;
77  uint8_t chunk_header[CHUNK_HEADER_LENGTH];
78  uint8_t ext_header[EXT_HEADER_LENGTH];
79  ChunkType chunk_type;
80  int chunk_len, res, ext_header_len;
81 
82  res = ffurl_read_complete(mms->mms_hd, chunk_header, CHUNK_HEADER_LENGTH);
83  if (res != CHUNK_HEADER_LENGTH) {
84  av_log(NULL, AV_LOG_ERROR, "Read data packet header failed!\n");
85  return AVERROR(EIO);
86  }
87  chunk_type = AV_RL16(chunk_header);
88  chunk_len = AV_RL16(chunk_header + 2);
89 
90  switch (chunk_type) {
91  case CHUNK_TYPE_END:
93  ext_header_len = 4;
94  break;
96  case CHUNK_TYPE_DATA:
97  ext_header_len = 8;
98  break;
99  default:
100  av_log(NULL, AV_LOG_ERROR, "Strange chunk type %d\n", chunk_type);
101  return AVERROR_INVALIDDATA;
102  }
103 
104  res = ffurl_read_complete(mms->mms_hd, ext_header, ext_header_len);
105  if (res != ext_header_len) {
106  av_log(NULL, AV_LOG_ERROR, "Read ext header failed!\n");
107  return AVERROR(EIO);
108  }
109  *len = chunk_len - ext_header_len;
110  if (chunk_type == CHUNK_TYPE_END || chunk_type == CHUNK_TYPE_DATA)
111  mmsh->chunk_seq = AV_RL32(ext_header);
112  return chunk_type;
113 }
114 
115 static int read_data_packet(MMSHContext *mmsh, const int len)
116 {
117  MMSContext *mms = &mmsh->mms;
118  int res;
119  if (len > sizeof(mms->in_buffer)) {
121  "Data packet length %d exceeds the in_buffer size %zu\n",
122  len, sizeof(mms->in_buffer));
123  return AVERROR(EIO);
124  }
125  res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len);
126  av_dlog(NULL, "Data packet len = %d\n", len);
127  if (res != len) {
128  av_log(NULL, AV_LOG_ERROR, "Read data packet failed!\n");
129  return AVERROR(EIO);
130  }
131  if (len > mms->asf_packet_len) {
133  "Chunk length %d exceed packet length %d\n",len, mms->asf_packet_len);
134  return AVERROR_INVALIDDATA;
135  } else {
136  memset(mms->in_buffer + len, 0, mms->asf_packet_len - len); // padding
137  }
138  mms->read_in_ptr = mms->in_buffer;
139  mms->remaining_in_len = mms->asf_packet_len;
140  return 0;
141 }
142 
144 {
145  MMSContext *mms = &mmsh->mms;
146  int res, len;
147  ChunkType chunk_type;
148 
149  for (;;) {
150  len = 0;
151  res = chunk_type = get_chunk_header(mmsh, &len);
152  if (res < 0) {
153  return res;
154  } else if (chunk_type == CHUNK_TYPE_ASF_HEADER){
155  // get asf header and stored it
156  if (!mms->header_parsed) {
157  if (mms->asf_header) {
158  if (len != mms->asf_header_size) {
159  mms->asf_header_size = len;
160  av_dlog(NULL, "Header len changed from %d to %d\n",
161  mms->asf_header_size, len);
162  av_freep(&mms->asf_header);
163  }
164  }
165  mms->asf_header = av_mallocz(len);
166  if (!mms->asf_header) {
167  return AVERROR(ENOMEM);
168  }
169  mms->asf_header_size = len;
170  }
171  if (len > mms->asf_header_size) {
173  "Asf header packet len = %d exceed the asf header buf size %d\n",
174  len, mms->asf_header_size);
175  return AVERROR(EIO);
176  }
177  res = ffurl_read_complete(mms->mms_hd, mms->asf_header, len);
178  if (res != len) {
180  "Recv asf header data len %d != expected len %d\n", res, len);
181  return AVERROR(EIO);
182  }
183  mms->asf_header_size = len;
184  if (!mms->header_parsed) {
185  res = ff_mms_asf_header_parser(mms);
186  mms->header_parsed = 1;
187  return res;
188  }
189  } else if (chunk_type == CHUNK_TYPE_DATA) {
190  // read data packet and do padding
191  return read_data_packet(mmsh, len);
192  } else {
193  if (len) {
194  if (len > sizeof(mms->in_buffer)) {
196  "Other packet len = %d exceed the in_buffer size %zu\n",
197  len, sizeof(mms->in_buffer));
198  return AVERROR(EIO);
199  }
200  res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len);
201  if (res != len) {
202  av_log(NULL, AV_LOG_ERROR, "Read other chunk type data failed!\n");
203  return AVERROR(EIO);
204  } else {
205  av_dlog(NULL, "Skip chunk type %d \n", chunk_type);
206  continue;
207  }
208  }
209  }
210  }
211 }
212 
213 static int mmsh_open(URLContext *h, const char *uri, int flags)
214 {
215  int i, port, err;
216  char httpname[256], path[256], host[128], location[1024];
217  char *stream_selection = NULL;
218  char headers[1024];
219  MMSHContext *mmsh = h->priv_data;
220  MMSContext *mms;
221 
222  mmsh->request_seq = h->is_streamed = 1;
223  mms = &mmsh->mms;
224  av_strlcpy(location, uri, sizeof(location));
225 
226  av_url_split(NULL, 0, NULL, 0,
227  host, sizeof(host), &port, path, sizeof(path), location);
228  if (port<0)
229  port = 80; // default mmsh protocol port
230  ff_url_join(httpname, sizeof(httpname), "http", NULL, host, port, "%s", path);
231 
232  if (ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ,
233  &h->interrupt_callback) < 0) {
234  return AVERROR(EIO);
235  }
236 
237  snprintf(headers, sizeof(headers),
238  "Accept: */*\r\n"
239  USERAGENT
240  "Host: %s:%d\r\n"
241  "Pragma: no-cache,rate=1.000000,stream-time=0,"
242  "stream-offset=0:0,request-context=%u,max-duration=0\r\n"
243  CLIENTGUID
244  "Connection: Close\r\n\r\n",
245  host, port, mmsh->request_seq++);
246  av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0);
247 
248  err = ffurl_connect(mms->mms_hd, NULL);
249  if (err) {
250  goto fail;
251  }
252  err = get_http_header_data(mmsh);
253  if (err) {
254  av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n");
255  goto fail;
256  }
257 
258  // close the socket and then reopen it for sending the second play request.
259  ffurl_close(mms->mms_hd);
260  memset(headers, 0, sizeof(headers));
261  if ((err = ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ,
262  &h->interrupt_callback)) < 0) {
263  goto fail;
264  }
265  stream_selection = av_mallocz(mms->stream_num * 19 + 1);
266  if (!stream_selection)
267  return AVERROR(ENOMEM);
268  for (i = 0; i < mms->stream_num; i++) {
269  char tmp[20];
270  err = snprintf(tmp, sizeof(tmp), "ffff:%d:0 ", mms->streams[i].id);
271  if (err < 0)
272  goto fail;
273  av_strlcat(stream_selection, tmp, mms->stream_num * 19 + 1);
274  }
275  // send play request
276  err = snprintf(headers, sizeof(headers),
277  "Accept: */*\r\n"
278  USERAGENT
279  "Host: %s:%d\r\n"
280  "Pragma: no-cache,rate=1.000000,request-context=%u\r\n"
281  "Pragma: xPlayStrm=1\r\n"
282  CLIENTGUID
283  "Pragma: stream-switch-count=%d\r\n"
284  "Pragma: stream-switch-entry=%s\r\n"
285  "Connection: Close\r\n\r\n",
286  host, port, mmsh->request_seq++, mms->stream_num, stream_selection);
287  av_freep(&stream_selection);
288  if (err < 0) {
289  av_log(NULL, AV_LOG_ERROR, "Build play request failed!\n");
290  goto fail;
291  }
292  av_dlog(NULL, "out_buffer is %s", headers);
293  av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0);
294 
295  err = ffurl_connect(mms->mms_hd, NULL);
296  if (err) {
297  goto fail;
298  }
299 
300  err = get_http_header_data(mmsh);
301  if (err) {
302  av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n");
303  goto fail;
304  }
305 
306  av_dlog(NULL, "Connection successfully open\n");
307  return 0;
308 fail:
309  av_freep(&stream_selection);
310  mmsh_close(h);
311  av_dlog(NULL, "Connection failed with error %d\n", err);
312  return err;
313 }
314 
316 {
317  MMSContext *mms = &mmsh->mms;
318  int res, len = 0;
319  ChunkType chunk_type;
320  chunk_type = get_chunk_header(mmsh, &len);
321 
322  switch (chunk_type) {
323  case CHUNK_TYPE_END:
324  mmsh->chunk_seq = 0;
325  av_log(NULL, AV_LOG_ERROR, "Stream ended!\n");
326  return AVERROR(EIO);
328  mms->header_parsed = 0;
329  if (res = get_http_header_data(mmsh)) {
330  av_log(NULL, AV_LOG_ERROR,"Stream changed! Failed to get new header!\n");
331  return res;
332  }
333  break;
334  case CHUNK_TYPE_DATA:
335  return read_data_packet(mmsh, len);
336  default:
337  av_log(NULL, AV_LOG_ERROR, "Recv other type packet %d\n", chunk_type);
338  return AVERROR_INVALIDDATA;
339  }
340  return 0;
341 }
342 
343 static int mmsh_read(URLContext *h, uint8_t *buf, int size)
344 {
345  int res = 0;
346  MMSHContext *mmsh = h->priv_data;
347  MMSContext *mms = &mmsh->mms;
348  do {
349  if (mms->asf_header_read_size < mms->asf_header_size) {
350  // copy asf header into buffer
351  res = ff_mms_read_header(mms, buf, size);
352  } else {
353  if (!mms->remaining_in_len && (res = handle_chunk_type(mmsh)))
354  return res;
355  res = ff_mms_read_data(mms, buf, size);
356  }
357  } while (!res);
358  return res;
359 }
360 
362  .name = "mmsh",
363  .url_open = mmsh_open,
364  .url_read = mmsh_read,
365  .url_close = mmsh_close,
366  .priv_data_size = sizeof(MMSHContext),
368 };