FFmpeg coverage

Line	Branch	Exec	Source
1			/*
2			* Pro-MPEG Code of Practice #3 Release 2 FEC
3			* Copyright (c) 2016 Mobibase, France (http://www.mobibase.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			* @file
24			* Pro-MPEG Code of Practice #3 Release 2 FEC protocol
25			* @author Vlad Tarca <vlad.tarca@gmail.com>
26			*/
27
28			/*
29			* Reminder:
30
31			[RFC 2733] FEC Packet Structure
32
33			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
34			| RTP Header |
35			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36			| FEC Header |
37			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38			| FEC Payload |
39			| |
40			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41
42
43			[RFC 3550] RTP header
44
45			0 1 2 3
46			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
47			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
48			|V=2|P|X| CC |M| PT | sequence number |
49			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
50			| timestamp |
51			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
52			| synchronization source (SSRC) identifier |
53			+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
54			| contributing source (CSRC) identifiers |
55			| .... |
56			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57
58			[RFC 3550] RTP header extension (after CSRC)
59
60			0 1 2 3
61			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
62			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63			| defined by profile | length |
64			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
65			| header extension |
66			| .... |
67			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
68
69			[Pro-MPEG COP3] FEC Header
70
71			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
72			| SNBase low bits | length recovery |
73			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
74			|E| PT recovery | mask |
75			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
76			| TS recovery |
77			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
78			|X|D|type |index| offset | NA |SNBase ext bits|
79			+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
80
81			*/
82
83			#include "libavutil/intreadwrite.h"
84			#include "libavutil/mem.h"
85			#include "libavutil/opt.h"
86			#include "libavutil/random_seed.h"
87			#include "avformat.h"
88			#include "config.h"
89			#include "url.h"
90
91			#define PROMPEG_RTP_PT 0x60
92			#define PROMPEG_FEC_COL 0x0
93			#define PROMPEG_FEC_ROW 0x1
94
95			typedef struct PrompegFec {
96			uint16_t sn;
97			uint32_t ts;
98			uint8_t *bitstring;
99			} PrompegFec;
100
101			typedef struct PrompegContext {
102			const AVClass *class;
103			URLContext *fec_col_hd, *fec_row_hd;
104			PrompegFec **fec_arr, **fec_col_tmp, **fec_col, *fec_row;
105			int ttl;
106			uint8_t l, d;
107			uint8_t *rtp_buf;
108			uint16_t rtp_col_sn, rtp_row_sn;
109			uint16_t length_recovery;
110			int packet_size;
111			int packet_idx, packet_idx_max;
112			int fec_arr_len;
113			int bitstring_size;
114			int rtp_buf_size;
115			int init;
116			int first;
117			} PrompegContext;
118
119			#define OFFSET(x) offsetof(PrompegContext, x)
120			#define E AV_OPT_FLAG_ENCODING_PARAM
121
122			static const AVOption options[] = {
123			{ "ttl", "Time to live (in milliseconds, multicast only)", OFFSET(ttl), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = E },
124			{ "l", "FEC L", OFFSET(l), AV_OPT_TYPE_INT, { .i64 = 5 }, 4, 20, .flags = E },
125			{ "d", "FEC D", OFFSET(d), AV_OPT_TYPE_INT, { .i64 = 5 }, 4, 20, .flags = E },
126			{ NULL }
127			};
128
129			static const AVClass prompeg_class = {
130			.class_name = "prompeg",
131			.item_name = av_default_item_name,
132			.option = options,
133			.version = LIBAVUTIL_VERSION_INT,
134			};
135
136		✗	static void xor_fast(const uint8_t *in1, const uint8_t *in2, uint8_t *out, int size) {
137			int i, n, s;
138
139			#if HAVE_FAST_64BIT
140			uint64_t v1, v2;
141
142		✗	n = size / sizeof (uint64_t);
143		✗	s = n * sizeof (uint64_t);
144
145		✗	for (i = 0; i < n; i++) {
146		✗	v1 = AV_RN64A(in1);
147		✗	v2 = AV_RN64A(in2);
148		✗	AV_WN64A(out, v1 ^ v2);
149		✗	in1 += 8;
150		✗	in2 += 8;
151		✗	out += 8;
152			}
153			#else
154			uint32_t v1, v2;
155
156			n = size / sizeof (uint32_t);
157			s = n * sizeof (uint32_t);
158
159			for (i = 0; i < n; i++) {
160			v1 = AV_RN32A(in1);
161			v2 = AV_RN32A(in2);
162			AV_WN32A(out, v1 ^ v2);
163			in1 += 4;
164			in2 += 4;
165			out += 4;
166			}
167			#endif
168
169		✗	n = size - s;
170
171		✗	for (i = 0; i < n; i++) {
172		✗	out[i] = in1[i] ^ in2[i];
173			}
174		✗	}
175
176		✗	static int prompeg_create_bitstring(URLContext *h, const uint8_t *buf, int size,
177			uint8_t **bitstring) {
178		✗	PrompegContext *s = h->priv_data;
179			uint8_t *b;
180
181		✗	if (size < 12 || (buf[0] & 0xc0) != 0x80 || (buf[1] & 0x7f) != 0x21) {
182		✗	av_log(h, AV_LOG_ERROR, "Unsupported stream format (expected MPEG-TS over RTP)\n");
183		✗	return AVERROR(EINVAL);
184			}
185		✗	if (size != s->packet_size) {
186		✗	av_log(h, AV_LOG_ERROR, "The RTP packet size must be constant (set pkt_size)\n");
187		✗	return AVERROR(EINVAL);
188			}
189
190		✗	*bitstring = av_malloc(s->bitstring_size);
191		✗	if (!*bitstring) {
192		✗	av_log(h, AV_LOG_ERROR, "Failed to allocate the bitstring buffer\n");
193		✗	return AVERROR(ENOMEM);
194			}
195		✗	b = *bitstring;
196
197			// P, X, CC
198		✗	b[0] = buf[0] & 0x3f;
199			// M, PT
200		✗	b[1] = buf[1];
201			// Timestamp
202		✗	b[2] = buf[4];
203		✗	b[3] = buf[5];
204		✗	b[4] = buf[6];
205		✗	b[5] = buf[7];
206			/*
207			* length_recovery: the unsigned network-ordered sum of lengths of CSRC,
208			* padding, extension and media payload
209			*/
210		✗	AV_WB16(b + 6, s->length_recovery);
211			// Payload
212		✗	memcpy(b + 8, buf + 12, s->length_recovery);
213
214		✗	return 0;
215			}
216
217		✗	static int prompeg_write_fec(URLContext *h, PrompegFec *fec, uint8_t type) {
218		✗	PrompegContext *s = h->priv_data;
219			URLContext *hd;
220		✗	uint8_t *buf = s->rtp_buf; // zero-filled
221		✗	uint8_t *b = fec->bitstring;
222			uint16_t sn;
223			int ret;
224
225		✗	sn = type == PROMPEG_FEC_COL ? ++s->rtp_col_sn : ++s->rtp_row_sn;
226
227			// V, P, X, CC
228		✗	buf[0] = 0x80 | (b[0] & 0x3f);
229			// M, PT
230		✗	buf[1] = (b[1] & 0x80) | PROMPEG_RTP_PT;
231			// SN
232		✗	AV_WB16(buf + 2, sn);
233			// TS
234		✗	AV_WB32(buf + 4, fec->ts);
235			// CSRC=0
236			//AV_WB32(buf + 8, 0);
237			// SNBase low bits
238		✗	AV_WB16(buf + 12, fec->sn);
239			// Length recovery
240		✗	buf[14] = b[6];
241		✗	buf[15] = b[7];
242			// E=1, PT recovery
243		✗	buf[16] = 0x80 | b[1];
244			// Mask=0
245			//buf[17] = 0x0;
246			//buf[18] = 0x0;
247			//buf[19] = 0x0;
248			// TS recovery
249		✗	buf[20] = b[2];
250		✗	buf[21] = b[3];
251		✗	buf[22] = b[4];
252		✗	buf[23] = b[5];
253			// X=0, D, type=0, index=0
254		✗	buf[24] = type == PROMPEG_FEC_COL ? 0x0 : 0x40;
255			// offset
256		✗	buf[25] = type == PROMPEG_FEC_COL ? s->l : 0x1;
257			// NA
258		✗	buf[26] = type == PROMPEG_FEC_COL ? s->d : s->l;
259			// SNBase ext bits=0
260			//buf[27] = 0x0;
261			// Payload
262		✗	memcpy(buf + 28, b + 8, s->length_recovery);
263
264		✗	hd = type == PROMPEG_FEC_COL ? s->fec_col_hd : s->fec_row_hd;
265		✗	ret = ffurl_write(hd, buf, s->rtp_buf_size);
266		✗	return ret;
267			}
268
269		✗	static int prompeg_open(URLContext *h, const char *uri, int flags) {
270		✗	PrompegContext *s = h->priv_data;
271		✗	AVDictionary *udp_opts = NULL;
272			int rtp_port;
273			char hostname[256];
274			char buf[1024];
275
276		✗	s->fec_col_hd = NULL;
277		✗	s->fec_row_hd = NULL;
278
279		✗	if (s->l * s->d > 100) {
280		✗	av_log(h, AV_LOG_ERROR, "L * D must be <= 100\n");
281		✗	return AVERROR(EINVAL);
282			}
283
284		✗	av_url_split(NULL, 0, NULL, 0, hostname, sizeof (hostname), &rtp_port,
285			NULL, 0, uri);
286
287		✗	if (rtp_port < 1 || rtp_port > UINT16_MAX - 4) {
288		✗	av_log(h, AV_LOG_ERROR, "Invalid RTP base port %d\n", rtp_port);
289		✗	return AVERROR(EINVAL);
290			}
291
292		✗	if (s->ttl > 0) {
293		✗	av_dict_set_int(&udp_opts, "ttl", s->ttl, 0);
294			}
295
296		✗	ff_url_join(buf, sizeof (buf), "udp", NULL, hostname, rtp_port + 2, NULL);
297		✗	if (ffurl_open_whitelist(&s->fec_col_hd, buf, flags, &h->interrupt_callback,
298			&udp_opts, h->protocol_whitelist, h->protocol_blacklist, h) < 0)
299		✗	goto fail;
300		✗	ff_url_join(buf, sizeof (buf), "udp", NULL, hostname, rtp_port + 4, NULL);
301		✗	if (ffurl_open_whitelist(&s->fec_row_hd, buf, flags, &h->interrupt_callback,
302			&udp_opts, h->protocol_whitelist, h->protocol_blacklist, h) < 0)
303		✗	goto fail;
304
305		✗	h->max_packet_size = s->fec_col_hd->max_packet_size;
306		✗	s->init = 1;
307
308		✗	av_dict_free(&udp_opts);
309		✗	av_log(h, AV_LOG_INFO, "ProMPEG CoP#3-R2 FEC L=%d D=%d\n", s->l, s->d);
310		✗	return 0;
311
312		✗	fail:
313		✗	ffurl_closep(&s->fec_col_hd);
314		✗	ffurl_closep(&s->fec_row_hd);
315		✗	av_dict_free(&udp_opts);
316		✗	return AVERROR(EIO);
317			}
318
319		✗	static int prompeg_init(URLContext *h, const uint8_t *buf, int size) {
320		✗	PrompegContext *s = h->priv_data;
321			uint32_t seed;
322			int i;
323
324		✗	s->fec_arr = NULL;
325		✗	s->rtp_buf = NULL;
326
327		✗	if (size < 12 || size > UINT16_MAX + 12) {
328		✗	av_log(h, AV_LOG_ERROR, "Invalid RTP packet size\n");
329		✗	return AVERROR_INVALIDDATA;
330			}
331
332		✗	s->packet_idx = 0;
333		✗	s->packet_idx_max = s->l * s->d;
334		✗	s->packet_size = size;
335		✗	s->length_recovery = size - 12;
336		✗	s->rtp_buf_size = 28 + s->length_recovery; // 12 + 16: RTP + FEC headers
337		✗	s->bitstring_size = 8 + s->length_recovery; // 8: P, X, CC, M, PT, SN, TS
338		✗	s->fec_arr_len = 1 + 2 * s->l; // row + column tmp + column out
339
340		✗	if (h->flags & AVFMT_FLAG_BITEXACT) {
341		✗	s->rtp_col_sn = 0;
342		✗	s->rtp_row_sn = 0;
343			} else {
344		✗	seed = av_get_random_seed();
345		✗	s->rtp_col_sn = seed & 0x0fff;
346		✗	s->rtp_row_sn = (seed >> 16) & 0x0fff;
347			}
348
349		✗	s->fec_arr = av_malloc_array(s->fec_arr_len, sizeof (PrompegFec*));
350		✗	if (!s->fec_arr) {
351		✗	goto fail;
352			}
353		✗	for (i = 0; i < s->fec_arr_len; i++) {
354		✗	s->fec_arr[i] = av_malloc(sizeof (PrompegFec));
355		✗	if (!s->fec_arr[i]) {
356		✗	goto fail;
357			}
358		✗	s->fec_arr[i]->bitstring = av_malloc_array(s->bitstring_size, sizeof (uint8_t));
359		✗	if (!s->fec_arr[i]->bitstring) {
360		✗	av_freep(&s->fec_arr[i]);
361		✗	goto fail;
362			}
363			}
364		✗	s->fec_row = *s->fec_arr;
365		✗	s->fec_col = s->fec_arr + 1;
366		✗	s->fec_col_tmp = s->fec_arr + 1 + s->l;
367
368		✗	s->rtp_buf = av_malloc_array(s->rtp_buf_size, sizeof (uint8_t));
369		✗	if (!s->rtp_buf) {
370		✗	goto fail;
371			}
372		✗	memset(s->rtp_buf, 0, s->rtp_buf_size);
373
374		✗	s->init = 0;
375		✗	s->first = 1;
376
377		✗	return 0;
378
379		✗	fail:
380		✗	av_log(h, AV_LOG_ERROR, "Failed to allocate the FEC buffer\n");
381		✗	return AVERROR(ENOMEM);
382			}
383
384		✗	static int prompeg_write(URLContext *h, const uint8_t *buf, int size) {
385		✗	PrompegContext *s = h->priv_data;
386			PrompegFec *fec_tmp;
387		✗	uint8_t *bitstring = NULL;
388			int col_idx, col_out_idx, row_idx;
389		✗	int ret = 0;
390
391		✗	if (s->init && ((ret = prompeg_init(h, buf, size)) < 0))
392		✗	goto end;
393
394		✗	if ((ret = prompeg_create_bitstring(h, buf, size, &bitstring)) < 0)
395		✗	goto end;
396
397		✗	col_idx = s->packet_idx % s->l;
398		✗	row_idx = s->packet_idx / s->l % s->d;
399
400			// FEC' (row) send block-aligned, xor
401		✗	if (col_idx == 0) {
402		✗	if (!s->first || s->packet_idx > 0) {
403		✗	if ((ret = prompeg_write_fec(h, s->fec_row, PROMPEG_FEC_ROW)) < 0)
404		✗	goto end;
405			}
406		✗	memcpy(s->fec_row->bitstring, bitstring, s->bitstring_size);
407		✗	s->fec_row->sn = AV_RB16(buf + 2);
408		✗	s->fec_row->ts = AV_RB32(buf + 4);
409			} else {
410		✗	xor_fast(s->fec_row->bitstring, bitstring, s->fec_row->bitstring,
411			s->bitstring_size);
412			}
413
414			// FEC (column) xor
415		✗	if (row_idx == 0) {
416		✗	if (!s->first) {
417			// swap fec_col and fec_col_tmp
418		✗	fec_tmp = s->fec_col[col_idx];
419		✗	s->fec_col[col_idx] = s->fec_col_tmp[col_idx];
420		✗	s->fec_col_tmp[col_idx] = fec_tmp;
421			}
422		✗	memcpy(s->fec_col_tmp[col_idx]->bitstring, bitstring, s->bitstring_size);
423		✗	s->fec_col_tmp[col_idx]->sn = AV_RB16(buf + 2);
424		✗	s->fec_col_tmp[col_idx]->ts = AV_RB32(buf + 4);
425			} else {
426		✗	xor_fast(s->fec_col_tmp[col_idx]->bitstring, bitstring,
427		✗	s->fec_col_tmp[col_idx]->bitstring, s->bitstring_size);
428			}
429
430			// FEC (column) send block-aligned
431		✗	if (!s->first && s->packet_idx % s->d == 0) {
432		✗	col_out_idx = s->packet_idx / s->d;
433		✗	if ((ret = prompeg_write_fec(h, s->fec_col[col_out_idx], PROMPEG_FEC_COL)) < 0)
434		✗	goto end;
435			}
436
437		✗	if (++s->packet_idx >= s->packet_idx_max) {
438		✗	s->packet_idx = 0;
439		✗	if (s->first)
440		✗	s->first = 0;
441			}
442
443		✗	ret = size;
444
445		✗	end:
446		✗	av_free(bitstring);
447		✗	return ret;
448			}
449
450		✗	static int prompeg_close(URLContext *h) {
451		✗	PrompegContext *s = h->priv_data;
452			int i;
453
454		✗	ffurl_closep(&s->fec_col_hd);
455		✗	ffurl_closep(&s->fec_row_hd);
456
457		✗	if (s->fec_arr) {
458		✗	for (i = 0; i < s->fec_arr_len; i++) {
459		✗	av_free(s->fec_arr[i]->bitstring);
460		✗	av_freep(&s->fec_arr[i]);
461			}
462		✗	av_freep(&s->fec_arr);
463			}
464		✗	av_freep(&s->rtp_buf);
465
466		✗	return 0;
467			}
468
469			const URLProtocol ff_prompeg_protocol = {
470			.name = "prompeg",
471			.url_open = prompeg_open,
472			.url_write = prompeg_write,
473			.url_close = prompeg_close,
474			.priv_data_size = sizeof(PrompegContext),
475			.flags = URL_PROTOCOL_FLAG_NETWORK,
476			.priv_data_class = &prompeg_class,
477			};
478