FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
rtmppkt.c
Go to the documentation of this file.
1 /*
2  * RTMP input format
3  * Copyright (c) 2009 Konstantin Shishkov
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 #include "libavcodec/bytestream.h"
23 #include "libavutil/avstring.h"
24 #include "libavutil/intfloat.h"
25 #include "avformat.h"
26 
27 #include "rtmppkt.h"
28 #include "flv.h"
29 #include "url.h"
30 
31 void ff_amf_write_bool(uint8_t **dst, int val)
32 {
33  bytestream_put_byte(dst, AMF_DATA_TYPE_BOOL);
34  bytestream_put_byte(dst, val);
35 }
36 
37 void ff_amf_write_number(uint8_t **dst, double val)
38 {
39  bytestream_put_byte(dst, AMF_DATA_TYPE_NUMBER);
40  bytestream_put_be64(dst, av_double2int(val));
41 }
42 
43 void ff_amf_write_string(uint8_t **dst, const char *str)
44 {
45  bytestream_put_byte(dst, AMF_DATA_TYPE_STRING);
46  bytestream_put_be16(dst, strlen(str));
47  bytestream_put_buffer(dst, str, strlen(str));
48 }
49 
50 void ff_amf_write_string2(uint8_t **dst, const char *str1, const char *str2)
51 {
52  int len1 = 0, len2 = 0;
53  if (str1)
54  len1 = strlen(str1);
55  if (str2)
56  len2 = strlen(str2);
57  bytestream_put_byte(dst, AMF_DATA_TYPE_STRING);
58  bytestream_put_be16(dst, len1 + len2);
59  bytestream_put_buffer(dst, str1, len1);
60  bytestream_put_buffer(dst, str2, len2);
61 }
62 
64 {
65  bytestream_put_byte(dst, AMF_DATA_TYPE_NULL);
66 }
67 
69 {
70  bytestream_put_byte(dst, AMF_DATA_TYPE_OBJECT);
71 }
72 
73 void ff_amf_write_field_name(uint8_t **dst, const char *str)
74 {
75  bytestream_put_be16(dst, strlen(str));
76  bytestream_put_buffer(dst, str, strlen(str));
77 }
78 
80 {
81  /* first two bytes are field name length = 0,
82  * AMF object should end with it and end marker
83  */
84  bytestream_put_be24(dst, AMF_DATA_TYPE_OBJECT_END);
85 }
86 
88 {
89  if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_BOOL)
90  return AVERROR_INVALIDDATA;
91  *val = bytestream2_get_byte(bc);
92  return 0;
93 }
94 
96 {
97  uint64_t read;
98  if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_NUMBER)
99  return AVERROR_INVALIDDATA;
100  read = bytestream2_get_be64(bc);
101  *val = av_int2double(read);
102  return 0;
103 }
104 
106  int strsize, int *length)
107 {
108  int stringlen = 0;
109  int readsize;
110  if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_STRING)
111  return AVERROR_INVALIDDATA;
112  stringlen = bytestream2_get_be16(bc);
113  if (stringlen + 1 > strsize)
114  return AVERROR(EINVAL);
115  readsize = bytestream2_get_buffer(bc, str, stringlen);
116  if (readsize != stringlen) {
117  av_log(NULL, AV_LOG_WARNING,
118  "Unable to read as many bytes as AMF string signaled\n");
119  }
120  str[readsize] = '\0';
121  *length = FFMIN(stringlen, readsize);
122  return 0;
123 }
124 
126 {
127  if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_NULL)
128  return AVERROR_INVALIDDATA;
129  return 0;
130 }
131 
133  int chunk_size, RTMPPacket *prev_pkt)
134 {
135  uint8_t hdr;
136 
137  if (ffurl_read(h, &hdr, 1) != 1)
138  return AVERROR(EIO);
139 
140  return ff_rtmp_packet_read_internal(h, p, chunk_size, prev_pkt, hdr);
141 }
142 
144  RTMPPacket *prev_pkt, uint8_t hdr)
145 {
146 
147  uint8_t t, buf[16];
148  int channel_id, timestamp, data_size, offset = 0;
149  uint32_t extra = 0;
150  enum RTMPPacketType type;
151  int size = 0;
152  int ret;
153 
154  size++;
155  channel_id = hdr & 0x3F;
156 
157  if (channel_id < 2) { //special case for channel number >= 64
158  buf[1] = 0;
159  if (ffurl_read_complete(h, buf, channel_id + 1) != channel_id + 1)
160  return AVERROR(EIO);
161  size += channel_id + 1;
162  channel_id = AV_RL16(buf) + 64;
163  }
164  data_size = prev_pkt[channel_id].data_size;
165  type = prev_pkt[channel_id].type;
166  extra = prev_pkt[channel_id].extra;
167 
168  hdr >>= 6;
169  if (hdr == RTMP_PS_ONEBYTE) {
170  timestamp = prev_pkt[channel_id].ts_delta;
171  } else {
172  if (ffurl_read_complete(h, buf, 3) != 3)
173  return AVERROR(EIO);
174  size += 3;
175  timestamp = AV_RB24(buf);
176  if (hdr != RTMP_PS_FOURBYTES) {
177  if (ffurl_read_complete(h, buf, 3) != 3)
178  return AVERROR(EIO);
179  size += 3;
180  data_size = AV_RB24(buf);
181  if (ffurl_read_complete(h, buf, 1) != 1)
182  return AVERROR(EIO);
183  size++;
184  type = buf[0];
185  if (hdr == RTMP_PS_TWELVEBYTES) {
186  if (ffurl_read_complete(h, buf, 4) != 4)
187  return AVERROR(EIO);
188  size += 4;
189  extra = AV_RL32(buf);
190  }
191  }
192  if (timestamp == 0xFFFFFF) {
193  if (ffurl_read_complete(h, buf, 4) != 4)
194  return AVERROR(EIO);
195  timestamp = AV_RB32(buf);
196  }
197  }
198  if (hdr != RTMP_PS_TWELVEBYTES)
199  timestamp += prev_pkt[channel_id].timestamp;
200 
201  if ((ret = ff_rtmp_packet_create(p, channel_id, type, timestamp,
202  data_size)) < 0)
203  return ret;
204  p->extra = extra;
205  // save history
206  prev_pkt[channel_id].channel_id = channel_id;
207  prev_pkt[channel_id].type = type;
208  prev_pkt[channel_id].data_size = data_size;
209  prev_pkt[channel_id].ts_delta = timestamp - prev_pkt[channel_id].timestamp;
210  prev_pkt[channel_id].timestamp = timestamp;
211  prev_pkt[channel_id].extra = extra;
212  while (data_size > 0) {
213  int toread = FFMIN(data_size, chunk_size);
214  if (ffurl_read_complete(h, p->data + offset, toread) != toread) {
216  return AVERROR(EIO);
217  }
218  data_size -= chunk_size;
219  offset += chunk_size;
220  size += chunk_size;
221  if (data_size > 0) {
222  if ((ret = ffurl_read_complete(h, &t, 1)) < 0) { // marker
224  return ret;
225  }
226  size++;
227  if (t != (0xC0 + channel_id))
228  return -1;
229  }
230  }
231  return size;
232 }
233 
235  int chunk_size, RTMPPacket *prev_pkt)
236 {
237  uint8_t pkt_hdr[16], *p = pkt_hdr;
239  int off = 0;
240  int size = 0;
241  int ret;
242 
243  pkt->ts_delta = pkt->timestamp - prev_pkt[pkt->channel_id].timestamp;
244 
245  //if channel_id = 0, this is first presentation of prev_pkt, send full hdr.
246  if (prev_pkt[pkt->channel_id].channel_id &&
247  pkt->extra == prev_pkt[pkt->channel_id].extra) {
248  if (pkt->type == prev_pkt[pkt->channel_id].type &&
249  pkt->data_size == prev_pkt[pkt->channel_id].data_size) {
250  mode = RTMP_PS_FOURBYTES;
251  if (pkt->ts_delta == prev_pkt[pkt->channel_id].ts_delta)
252  mode = RTMP_PS_ONEBYTE;
253  } else {
254  mode = RTMP_PS_EIGHTBYTES;
255  }
256  }
257 
258  if (pkt->channel_id < 64) {
259  bytestream_put_byte(&p, pkt->channel_id | (mode << 6));
260  } else if (pkt->channel_id < 64 + 256) {
261  bytestream_put_byte(&p, 0 | (mode << 6));
262  bytestream_put_byte(&p, pkt->channel_id - 64);
263  } else {
264  bytestream_put_byte(&p, 1 | (mode << 6));
265  bytestream_put_le16(&p, pkt->channel_id - 64);
266  }
267  if (mode != RTMP_PS_ONEBYTE) {
268  uint32_t timestamp = pkt->timestamp;
269  if (mode != RTMP_PS_TWELVEBYTES)
270  timestamp = pkt->ts_delta;
271  bytestream_put_be24(&p, timestamp >= 0xFFFFFF ? 0xFFFFFF : timestamp);
272  if (mode != RTMP_PS_FOURBYTES) {
273  bytestream_put_be24(&p, pkt->data_size);
274  bytestream_put_byte(&p, pkt->type);
275  if (mode == RTMP_PS_TWELVEBYTES)
276  bytestream_put_le32(&p, pkt->extra);
277  }
278  if (timestamp >= 0xFFFFFF)
279  bytestream_put_be32(&p, timestamp);
280  }
281  // save history
282  prev_pkt[pkt->channel_id].channel_id = pkt->channel_id;
283  prev_pkt[pkt->channel_id].type = pkt->type;
284  prev_pkt[pkt->channel_id].data_size = pkt->data_size;
285  prev_pkt[pkt->channel_id].timestamp = pkt->timestamp;
286  if (mode != RTMP_PS_TWELVEBYTES) {
287  prev_pkt[pkt->channel_id].ts_delta = pkt->ts_delta;
288  } else {
289  prev_pkt[pkt->channel_id].ts_delta = pkt->timestamp;
290  }
291  prev_pkt[pkt->channel_id].extra = pkt->extra;
292 
293  if ((ret = ffurl_write(h, pkt_hdr, p - pkt_hdr)) < 0)
294  return ret;
295  size = p - pkt_hdr + pkt->data_size;
296  while (off < pkt->data_size) {
297  int towrite = FFMIN(chunk_size, pkt->data_size - off);
298  if ((ret = ffurl_write(h, pkt->data + off, towrite)) < 0)
299  return ret;
300  off += towrite;
301  if (off < pkt->data_size) {
302  uint8_t marker = 0xC0 | pkt->channel_id;
303  if ((ret = ffurl_write(h, &marker, 1)) < 0)
304  return ret;
305  size++;
306  }
307  }
308  return size;
309 }
310 
312  int timestamp, int size)
313 {
314  if (size) {
315  pkt->data = av_malloc(size);
316  if (!pkt->data)
317  return AVERROR(ENOMEM);
318  }
319  pkt->data_size = size;
320  pkt->channel_id = channel_id;
321  pkt->type = type;
322  pkt->timestamp = timestamp;
323  pkt->extra = 0;
324  pkt->ts_delta = 0;
325 
326  return 0;
327 }
328 
330 {
331  if (!pkt)
332  return;
333  av_freep(&pkt->data);
334  pkt->data_size = 0;
335 }
336 
337 int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end)
338 {
339  const uint8_t *base = data;
340 
341  if (data >= data_end)
342  return -1;
343  switch (*data++) {
344  case AMF_DATA_TYPE_NUMBER: return 9;
345  case AMF_DATA_TYPE_BOOL: return 2;
346  case AMF_DATA_TYPE_STRING: return 3 + AV_RB16(data);
347  case AMF_DATA_TYPE_LONG_STRING: return 5 + AV_RB32(data);
348  case AMF_DATA_TYPE_NULL: return 1;
349  case AMF_DATA_TYPE_ARRAY:
350  data += 4;
352  for (;;) {
353  int size = bytestream_get_be16(&data);
354  int t;
355  if (!size) {
356  data++;
357  break;
358  }
359  if (size < 0 || size >= data_end - data)
360  return -1;
361  data += size;
362  t = ff_amf_tag_size(data, data_end);
363  if (t < 0 || t >= data_end - data)
364  return -1;
365  data += t;
366  }
367  return data - base;
368  case AMF_DATA_TYPE_OBJECT_END: return 1;
369  default: return -1;
370  }
371 }
372 
373 int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
374  const uint8_t *name, uint8_t *dst, int dst_size)
375 {
376  int namelen = strlen(name);
377  int len;
378 
379  while (*data != AMF_DATA_TYPE_OBJECT && data < data_end) {
380  len = ff_amf_tag_size(data, data_end);
381  if (len < 0)
382  len = data_end - data;
383  data += len;
384  }
385  if (data_end - data < 3)
386  return -1;
387  data++;
388  for (;;) {
389  int size = bytestream_get_be16(&data);
390  if (!size)
391  break;
392  if (size < 0 || size >= data_end - data)
393  return -1;
394  data += size;
395  if (size == namelen && !memcmp(data-size, name, namelen)) {
396  switch (*data++) {
398  snprintf(dst, dst_size, "%g", av_int2double(AV_RB64(data)));
399  break;
400  case AMF_DATA_TYPE_BOOL:
401  snprintf(dst, dst_size, "%s", *data ? "true" : "false");
402  break;
404  len = bytestream_get_be16(&data);
405  av_strlcpy(dst, data, FFMIN(len+1, dst_size));
406  break;
407  default:
408  return -1;
409  }
410  return 0;
411  }
412  len = ff_amf_tag_size(data, data_end);
413  if (len < 0 || len >= data_end - data)
414  return -1;
415  data += len;
416  }
417  return -1;
418 }
419 
420 static const char* rtmp_packet_type(int type)
421 {
422  switch (type) {
423  case RTMP_PT_CHUNK_SIZE: return "chunk size";
424  case RTMP_PT_BYTES_READ: return "bytes read";
425  case RTMP_PT_PING: return "ping";
426  case RTMP_PT_SERVER_BW: return "server bandwidth";
427  case RTMP_PT_CLIENT_BW: return "client bandwidth";
428  case RTMP_PT_AUDIO: return "audio packet";
429  case RTMP_PT_VIDEO: return "video packet";
430  case RTMP_PT_FLEX_STREAM: return "Flex shared stream";
431  case RTMP_PT_FLEX_OBJECT: return "Flex shared object";
432  case RTMP_PT_FLEX_MESSAGE: return "Flex shared message";
433  case RTMP_PT_NOTIFY: return "notification";
434  case RTMP_PT_SHARED_OBJ: return "shared object";
435  case RTMP_PT_INVOKE: return "invoke";
436  case RTMP_PT_METADATA: return "metadata";
437  default: return "unknown";
438  }
439 }
440 
441 static void amf_tag_contents(void *ctx, const uint8_t *data,
442  const uint8_t *data_end)
443 {
444  unsigned int size;
445  char buf[1024];
446 
447  if (data >= data_end)
448  return;
449  switch (*data++) {
451  av_log(ctx, AV_LOG_DEBUG, " number %g\n", av_int2double(AV_RB64(data)));
452  return;
453  case AMF_DATA_TYPE_BOOL:
454  av_log(ctx, AV_LOG_DEBUG, " bool %d\n", *data);
455  return;
458  if (data[-1] == AMF_DATA_TYPE_STRING) {
459  size = bytestream_get_be16(&data);
460  } else {
461  size = bytestream_get_be32(&data);
462  }
463  size = FFMIN(size, sizeof(buf) - 1);
464  memcpy(buf, data, size);
465  buf[size] = 0;
466  av_log(ctx, AV_LOG_DEBUG, " string '%s'\n", buf);
467  return;
468  case AMF_DATA_TYPE_NULL:
469  av_log(ctx, AV_LOG_DEBUG, " NULL\n");
470  return;
471  case AMF_DATA_TYPE_ARRAY:
472  data += 4;
474  av_log(ctx, AV_LOG_DEBUG, " {\n");
475  for (;;) {
476  int t;
477  size = bytestream_get_be16(&data);
478  av_strlcpy(buf, data, FFMIN(sizeof(buf), size + 1));
479  if (!size) {
480  av_log(ctx, AV_LOG_DEBUG, " }\n");
481  data++;
482  break;
483  }
484  if (size >= data_end - data)
485  return;
486  data += size;
487  av_log(ctx, AV_LOG_DEBUG, " %s: ", buf);
488  amf_tag_contents(ctx, data, data_end);
489  t = ff_amf_tag_size(data, data_end);
490  if (t < 0 || t >= data_end - data)
491  return;
492  data += t;
493  }
494  return;
496  av_log(ctx, AV_LOG_DEBUG, " }\n");
497  return;
498  default:
499  return;
500  }
501 }
502 
503 void ff_rtmp_packet_dump(void *ctx, RTMPPacket *p)
504 {
505  av_log(ctx, AV_LOG_DEBUG, "RTMP packet type '%s'(%d) for channel %d, timestamp %d, extra field %d size %d\n",
506  rtmp_packet_type(p->type), p->type, p->channel_id, p->timestamp, p->extra, p->data_size);
507  if (p->type == RTMP_PT_INVOKE || p->type == RTMP_PT_NOTIFY) {
508  uint8_t *src = p->data, *src_end = p->data + p->data_size;
509  while (src < src_end) {
510  int sz;
511  amf_tag_contents(ctx, src, src_end);
512  sz = ff_amf_tag_size(src, src_end);
513  if (sz < 0)
514  break;
515  src += sz;
516  }
517  } else if (p->type == RTMP_PT_SERVER_BW){
518  av_log(ctx, AV_LOG_DEBUG, "Server BW = %d\n", AV_RB32(p->data));
519  } else if (p->type == RTMP_PT_CLIENT_BW){
520  av_log(ctx, AV_LOG_DEBUG, "Client BW = %d\n", AV_RB32(p->data));
521  } else if (p->type != RTMP_PT_AUDIO && p->type != RTMP_PT_VIDEO && p->type != RTMP_PT_METADATA) {
522  int i;
523  for (i = 0; i < p->data_size; i++)
524  av_log(ctx, AV_LOG_DEBUG, " %02X", p->data[i]);
525  av_log(ctx, AV_LOG_DEBUG, "\n");
526  }
527 }