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rtmppkt.c
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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  stringlen = bytestream2_get_be16(bc);
111  if (stringlen + 1 > strsize)
112  return AVERROR(EINVAL);
113  readsize = bytestream2_get_buffer(bc, str, stringlen);
114  if (readsize != stringlen) {
115  av_log(NULL, AV_LOG_WARNING,
116  "Unable to read as many bytes as AMF string signaled\n");
117  }
118  str[readsize] = '\0';
119  *length = FFMIN(stringlen, readsize);
120  return 0;
121 }
122 
124  int strsize, int *length)
125 {
126  if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_STRING)
127  return AVERROR_INVALIDDATA;
128  return ff_amf_get_string(bc, str, strsize, length);
129 }
130 
132 {
133  if (bytestream2_get_byte(bc) != AMF_DATA_TYPE_NULL)
134  return AVERROR_INVALIDDATA;
135  return 0;
136 }
137 
138 int ff_rtmp_check_alloc_array(RTMPPacket **prev_pkt, int *nb_prev_pkt,
139  int channel)
140 {
141  int nb_alloc;
142  RTMPPacket *ptr;
143  if (channel < *nb_prev_pkt)
144  return 0;
145 
146  nb_alloc = channel + 16;
147  // This can't use the av_reallocp family of functions, since we
148  // would need to free each element in the array before the array
149  // itself is freed.
150  ptr = av_realloc_array(*prev_pkt, nb_alloc, sizeof(**prev_pkt));
151  if (!ptr)
152  return AVERROR(ENOMEM);
153  memset(ptr + *nb_prev_pkt, 0, (nb_alloc - *nb_prev_pkt) * sizeof(*ptr));
154  *prev_pkt = ptr;
155  *nb_prev_pkt = nb_alloc;
156  return 0;
157 }
158 
160  int chunk_size, RTMPPacket **prev_pkt, int *nb_prev_pkt)
161 {
162  uint8_t hdr;
163 
164  if (ffurl_read(h, &hdr, 1) != 1)
165  return AVERROR(EIO);
166 
167  return ff_rtmp_packet_read_internal(h, p, chunk_size, prev_pkt,
168  nb_prev_pkt, hdr);
169 }
170 
172  int chunk_size, RTMPPacket **prev_pkt_ptr,
173  int *nb_prev_pkt, uint8_t hdr)
174 {
175 
176  uint8_t buf[16];
177  int channel_id, timestamp, size;
178  uint32_t ts_field; // non-extended timestamp or delta field
179  uint32_t extra = 0;
180  enum RTMPPacketType type;
181  int written = 0;
182  int ret, toread;
183  RTMPPacket *prev_pkt;
184 
185  written++;
186  channel_id = hdr & 0x3F;
187 
188  if (channel_id < 2) { //special case for channel number >= 64
189  buf[1] = 0;
190  if (ffurl_read_complete(h, buf, channel_id + 1) != channel_id + 1)
191  return AVERROR(EIO);
192  written += channel_id + 1;
193  channel_id = AV_RL16(buf) + 64;
194  }
195  if ((ret = ff_rtmp_check_alloc_array(prev_pkt_ptr, nb_prev_pkt,
196  channel_id)) < 0)
197  return ret;
198  prev_pkt = *prev_pkt_ptr;
199  size = prev_pkt[channel_id].size;
200  type = prev_pkt[channel_id].type;
201  extra = prev_pkt[channel_id].extra;
202 
203  hdr >>= 6; // header size indicator
204  if (hdr == RTMP_PS_ONEBYTE) {
205  ts_field = prev_pkt[channel_id].ts_field;
206  } else {
207  if (ffurl_read_complete(h, buf, 3) != 3)
208  return AVERROR(EIO);
209  written += 3;
210  ts_field = AV_RB24(buf);
211  if (hdr != RTMP_PS_FOURBYTES) {
212  if (ffurl_read_complete(h, buf, 3) != 3)
213  return AVERROR(EIO);
214  written += 3;
215  size = AV_RB24(buf);
216  if (ffurl_read_complete(h, buf, 1) != 1)
217  return AVERROR(EIO);
218  written++;
219  type = buf[0];
220  if (hdr == RTMP_PS_TWELVEBYTES) {
221  if (ffurl_read_complete(h, buf, 4) != 4)
222  return AVERROR(EIO);
223  written += 4;
224  extra = AV_RL32(buf);
225  }
226  }
227  }
228  if (ts_field == 0xFFFFFF) {
229  if (ffurl_read_complete(h, buf, 4) != 4)
230  return AVERROR(EIO);
231  timestamp = AV_RB32(buf);
232  } else {
233  timestamp = ts_field;
234  }
235  if (hdr != RTMP_PS_TWELVEBYTES)
236  timestamp += prev_pkt[channel_id].timestamp;
237 
238  if (!prev_pkt[channel_id].read) {
239  if ((ret = ff_rtmp_packet_create(p, channel_id, type, timestamp,
240  size)) < 0)
241  return ret;
242  p->read = written;
243  p->offset = 0;
244  prev_pkt[channel_id].ts_field = ts_field;
245  prev_pkt[channel_id].timestamp = timestamp;
246  } else {
247  // previous packet in this channel hasn't completed reading
248  RTMPPacket *prev = &prev_pkt[channel_id];
249  p->data = prev->data;
250  p->size = prev->size;
251  p->channel_id = prev->channel_id;
252  p->type = prev->type;
253  p->ts_field = prev->ts_field;
254  p->extra = prev->extra;
255  p->offset = prev->offset;
256  p->read = prev->read + written;
257  p->timestamp = prev->timestamp;
258  prev->data = NULL;
259  }
260  p->extra = extra;
261  // save history
262  prev_pkt[channel_id].channel_id = channel_id;
263  prev_pkt[channel_id].type = type;
264  prev_pkt[channel_id].size = size;
265  prev_pkt[channel_id].extra = extra;
266  size = size - p->offset;
267 
268  toread = FFMIN(size, chunk_size);
269  if (ffurl_read_complete(h, p->data + p->offset, toread) != toread) {
271  return AVERROR(EIO);
272  }
273  size -= toread;
274  p->read += toread;
275  p->offset += toread;
276 
277  if (size > 0) {
278  RTMPPacket *prev = &prev_pkt[channel_id];
279  prev->data = p->data;
280  prev->read = p->read;
281  prev->offset = p->offset;
282  p->data = NULL;
283  return AVERROR(EAGAIN);
284  }
285 
286  prev_pkt[channel_id].read = 0; // read complete; reset if needed
287  return p->read;
288 }
289 
291  RTMPPacket **prev_pkt, int *nb_prev_pkt,
292  uint8_t hdr)
293 {
294  while (1) {
295  int ret = rtmp_packet_read_one_chunk(h, p, chunk_size, prev_pkt,
296  nb_prev_pkt, hdr);
297  if (ret > 0 || ret != AVERROR(EAGAIN))
298  return ret;
299 
300  if (ffurl_read(h, &hdr, 1) != 1)
301  return AVERROR(EIO);
302  }
303 }
304 
306  int chunk_size, RTMPPacket **prev_pkt_ptr,
307  int *nb_prev_pkt)
308 {
309  uint8_t pkt_hdr[16], *p = pkt_hdr;
311  int off = 0;
312  int written = 0;
313  int ret;
314  RTMPPacket *prev_pkt;
315  int use_delta; // flag if using timestamp delta, not RTMP_PS_TWELVEBYTES
316  uint32_t timestamp; // full 32-bit timestamp or delta value
317 
318  if ((ret = ff_rtmp_check_alloc_array(prev_pkt_ptr, nb_prev_pkt,
319  pkt->channel_id)) < 0)
320  return ret;
321  prev_pkt = *prev_pkt_ptr;
322 
323  //if channel_id = 0, this is first presentation of prev_pkt, send full hdr.
324  use_delta = prev_pkt[pkt->channel_id].channel_id &&
325  pkt->extra == prev_pkt[pkt->channel_id].extra &&
326  pkt->timestamp >= prev_pkt[pkt->channel_id].timestamp;
327 
328  timestamp = pkt->timestamp;
329  if (use_delta) {
330  timestamp -= prev_pkt[pkt->channel_id].timestamp;
331  }
332  if (timestamp >= 0xFFFFFF) {
333  pkt->ts_field = 0xFFFFFF;
334  } else {
335  pkt->ts_field = timestamp;
336  }
337 
338  if (use_delta) {
339  if (pkt->type == prev_pkt[pkt->channel_id].type &&
340  pkt->size == prev_pkt[pkt->channel_id].size) {
341  mode = RTMP_PS_FOURBYTES;
342  if (pkt->ts_field == prev_pkt[pkt->channel_id].ts_field)
343  mode = RTMP_PS_ONEBYTE;
344  } else {
345  mode = RTMP_PS_EIGHTBYTES;
346  }
347  }
348 
349  if (pkt->channel_id < 64) {
350  bytestream_put_byte(&p, pkt->channel_id | (mode << 6));
351  } else if (pkt->channel_id < 64 + 256) {
352  bytestream_put_byte(&p, 0 | (mode << 6));
353  bytestream_put_byte(&p, pkt->channel_id - 64);
354  } else {
355  bytestream_put_byte(&p, 1 | (mode << 6));
356  bytestream_put_le16(&p, pkt->channel_id - 64);
357  }
358  if (mode != RTMP_PS_ONEBYTE) {
359  bytestream_put_be24(&p, pkt->ts_field);
360  if (mode != RTMP_PS_FOURBYTES) {
361  bytestream_put_be24(&p, pkt->size);
362  bytestream_put_byte(&p, pkt->type);
363  if (mode == RTMP_PS_TWELVEBYTES)
364  bytestream_put_le32(&p, pkt->extra);
365  }
366  }
367  if (pkt->ts_field == 0xFFFFFF)
368  bytestream_put_be32(&p, timestamp);
369  // save history
370  prev_pkt[pkt->channel_id].channel_id = pkt->channel_id;
371  prev_pkt[pkt->channel_id].type = pkt->type;
372  prev_pkt[pkt->channel_id].size = pkt->size;
373  prev_pkt[pkt->channel_id].timestamp = pkt->timestamp;
374  prev_pkt[pkt->channel_id].ts_field = pkt->ts_field;
375  prev_pkt[pkt->channel_id].extra = pkt->extra;
376 
377  if ((ret = ffurl_write(h, pkt_hdr, p - pkt_hdr)) < 0)
378  return ret;
379  written = p - pkt_hdr + pkt->size;
380  while (off < pkt->size) {
381  int towrite = FFMIN(chunk_size, pkt->size - off);
382  if ((ret = ffurl_write(h, pkt->data + off, towrite)) < 0)
383  return ret;
384  off += towrite;
385  if (off < pkt->size) {
386  uint8_t marker = 0xC0 | pkt->channel_id;
387  if ((ret = ffurl_write(h, &marker, 1)) < 0)
388  return ret;
389  written++;
390  if (pkt->ts_field == 0xFFFFFF) {
391  uint8_t ts_header[4];
392  AV_WB32(ts_header, timestamp);
393  if ((ret = ffurl_write(h, ts_header, 4)) < 0)
394  return ret;
395  written += 4;
396  }
397  }
398  }
399  return written;
400 }
401 
403  int timestamp, int size)
404 {
405  if (size) {
406  pkt->data = av_realloc(NULL, size);
407  if (!pkt->data)
408  return AVERROR(ENOMEM);
409  }
410  pkt->size = size;
411  pkt->channel_id = channel_id;
412  pkt->type = type;
413  pkt->timestamp = timestamp;
414  pkt->extra = 0;
415  pkt->ts_field = 0;
416 
417  return 0;
418 }
419 
421 {
422  if (!pkt)
423  return;
424  av_freep(&pkt->data);
425  pkt->size = 0;
426 }
427 
428 int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end)
429 {
430  const uint8_t *base = data;
432  unsigned nb = -1;
433  int parse_key = 1;
434 
435  if (data >= data_end)
436  return -1;
437  switch ((type = *data++)) {
438  case AMF_DATA_TYPE_NUMBER: return 9;
439  case AMF_DATA_TYPE_BOOL: return 2;
440  case AMF_DATA_TYPE_STRING: return 3 + AV_RB16(data);
441  case AMF_DATA_TYPE_LONG_STRING: return 5 + AV_RB32(data);
442  case AMF_DATA_TYPE_NULL: return 1;
443  case AMF_DATA_TYPE_ARRAY:
444  parse_key = 0;
446  nb = bytestream_get_be32(&data);
448  while (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY) {
449  int t;
450  if (parse_key) {
451  int size = bytestream_get_be16(&data);
452  if (!size) {
453  data++;
454  break;
455  }
456  if (size < 0 || size >= data_end - data)
457  return -1;
458  data += size;
459  }
460  t = ff_amf_tag_size(data, data_end);
461  if (t < 0 || t >= data_end - data)
462  return -1;
463  data += t;
464  }
465  return data - base;
466  case AMF_DATA_TYPE_OBJECT_END: return 1;
467  default: return -1;
468  }
469 }
470 
471 int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
472  const uint8_t *name, uint8_t *dst, int dst_size)
473 {
474  int namelen = strlen(name);
475  int len;
476 
477  while (*data != AMF_DATA_TYPE_OBJECT && data < data_end) {
478  len = ff_amf_tag_size(data, data_end);
479  if (len < 0)
480  len = data_end - data;
481  data += len;
482  }
483  if (data_end - data < 3)
484  return -1;
485  data++;
486  for (;;) {
487  int size = bytestream_get_be16(&data);
488  if (!size)
489  break;
490  if (size < 0 || size >= data_end - data)
491  return -1;
492  data += size;
493  if (size == namelen && !memcmp(data-size, name, namelen)) {
494  switch (*data++) {
496  snprintf(dst, dst_size, "%g", av_int2double(AV_RB64(data)));
497  break;
498  case AMF_DATA_TYPE_BOOL:
499  snprintf(dst, dst_size, "%s", *data ? "true" : "false");
500  break;
502  len = bytestream_get_be16(&data);
503  av_strlcpy(dst, data, FFMIN(len+1, dst_size));
504  break;
505  default:
506  return -1;
507  }
508  return 0;
509  }
510  len = ff_amf_tag_size(data, data_end);
511  if (len < 0 || len >= data_end - data)
512  return -1;
513  data += len;
514  }
515  return -1;
516 }
517 
518 static const char* rtmp_packet_type(int type)
519 {
520  switch (type) {
521  case RTMP_PT_CHUNK_SIZE: return "chunk size";
522  case RTMP_PT_BYTES_READ: return "bytes read";
523  case RTMP_PT_PING: return "ping";
524  case RTMP_PT_SERVER_BW: return "server bandwidth";
525  case RTMP_PT_CLIENT_BW: return "client bandwidth";
526  case RTMP_PT_AUDIO: return "audio packet";
527  case RTMP_PT_VIDEO: return "video packet";
528  case RTMP_PT_FLEX_STREAM: return "Flex shared stream";
529  case RTMP_PT_FLEX_OBJECT: return "Flex shared object";
530  case RTMP_PT_FLEX_MESSAGE: return "Flex shared message";
531  case RTMP_PT_NOTIFY: return "notification";
532  case RTMP_PT_SHARED_OBJ: return "shared object";
533  case RTMP_PT_INVOKE: return "invoke";
534  case RTMP_PT_METADATA: return "metadata";
535  default: return "unknown";
536  }
537 }
538 
539 static void amf_tag_contents(void *ctx, const uint8_t *data,
540  const uint8_t *data_end)
541 {
542  unsigned int size, nb = -1;
543  char buf[1024];
545  int parse_key = 1;
546 
547  if (data >= data_end)
548  return;
549  switch ((type = *data++)) {
551  av_log(ctx, AV_LOG_DEBUG, " number %g\n", av_int2double(AV_RB64(data)));
552  return;
553  case AMF_DATA_TYPE_BOOL:
554  av_log(ctx, AV_LOG_DEBUG, " bool %d\n", *data);
555  return;
558  if (type == AMF_DATA_TYPE_STRING) {
559  size = bytestream_get_be16(&data);
560  } else {
561  size = bytestream_get_be32(&data);
562  }
563  size = FFMIN(size, sizeof(buf) - 1);
564  memcpy(buf, data, size);
565  buf[size] = 0;
566  av_log(ctx, AV_LOG_DEBUG, " string '%s'\n", buf);
567  return;
568  case AMF_DATA_TYPE_NULL:
569  av_log(ctx, AV_LOG_DEBUG, " NULL\n");
570  return;
571  case AMF_DATA_TYPE_ARRAY:
572  parse_key = 0;
574  nb = bytestream_get_be32(&data);
576  av_log(ctx, AV_LOG_DEBUG, " {\n");
577  while (nb-- > 0 || type != AMF_DATA_TYPE_ARRAY) {
578  int t;
579  if (parse_key) {
580  size = bytestream_get_be16(&data);
581  size = FFMIN(size, sizeof(buf) - 1);
582  if (!size) {
583  av_log(ctx, AV_LOG_DEBUG, " }\n");
584  data++;
585  break;
586  }
587  memcpy(buf, data, size);
588  buf[size] = 0;
589  if (size >= data_end - data)
590  return;
591  data += size;
592  av_log(ctx, AV_LOG_DEBUG, " %s: ", buf);
593  }
594  amf_tag_contents(ctx, data, data_end);
595  t = ff_amf_tag_size(data, data_end);
596  if (t < 0 || t >= data_end - data)
597  return;
598  data += t;
599  }
600  return;
602  av_log(ctx, AV_LOG_DEBUG, " }\n");
603  return;
604  default:
605  return;
606  }
607 }
608 
609 void ff_rtmp_packet_dump(void *ctx, RTMPPacket *p)
610 {
611  av_log(ctx, AV_LOG_DEBUG, "RTMP packet type '%s'(%d) for channel %d, timestamp %d, extra field %d size %d\n",
612  rtmp_packet_type(p->type), p->type, p->channel_id, p->timestamp, p->extra, p->size);
613  if (p->type == RTMP_PT_INVOKE || p->type == RTMP_PT_NOTIFY) {
614  uint8_t *src = p->data, *src_end = p->data + p->size;
615  while (src < src_end) {
616  int sz;
617  amf_tag_contents(ctx, src, src_end);
618  sz = ff_amf_tag_size(src, src_end);
619  if (sz < 0)
620  break;
621  src += sz;
622  }
623  } else if (p->type == RTMP_PT_SERVER_BW){
624  av_log(ctx, AV_LOG_DEBUG, "Server BW = %d\n", AV_RB32(p->data));
625  } else if (p->type == RTMP_PT_CLIENT_BW){
626  av_log(ctx, AV_LOG_DEBUG, "Client BW = %d\n", AV_RB32(p->data));
627  } else if (p->type != RTMP_PT_AUDIO && p->type != RTMP_PT_VIDEO && p->type != RTMP_PT_METADATA) {
628  int i;
629  for (i = 0; i < p->size; i++)
630  av_log(ctx, AV_LOG_DEBUG, " %02X", p->data[i]);
631  av_log(ctx, AV_LOG_DEBUG, "\n");
632  }
633 }
634 
635 int ff_amf_match_string(const uint8_t *data, int size, const char *str)
636 {
637  int len = strlen(str);
638  int amf_len, type;
639 
640  if (size < 1)
641  return 0;
642 
643  type = *data++;
644 
645  if (type != AMF_DATA_TYPE_LONG_STRING &&
646  type != AMF_DATA_TYPE_STRING)
647  return 0;
648 
649  if (type == AMF_DATA_TYPE_LONG_STRING) {
650  if ((size -= 4 + 1) < 0)
651  return 0;
652  amf_len = bytestream_get_be32(&data);
653  } else {
654  if ((size -= 2 + 1) < 0)
655  return 0;
656  amf_len = bytestream_get_be16(&data);
657  }
658 
659  if (amf_len > size)
660  return 0;
661 
662  if (amf_len != len)
663  return 0;
664 
665  return !memcmp(data, str, len);
666 }