From 59c6178a54c414fd19e064f0077d00b82a1eb812 Mon Sep 17 00:00:00 2001
From: Justin Ruggles <justin.ruggles@gmail.com>
Date: Thu, 26 Feb 2009 02:29:24 +0000
Subject: [PATCH] Use a shared function to validate FLAC extradata.
Originally committed as revision 17602 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
libavcodec/Makefile | 7 +++---
libavcodec/flac.h | 16 +++++++++++++
libavcodec/flacdec.c | 47 +++++++++++++++++++++++++++++++--------
libavformat/flacenc.c | 25 ++++++++++++++++-----
libavformat/matroskaenc.c | 16 ++++++-------
libavformat/oggenc.c | 11 +++++----
6 files changed, 91 insertions(+), 31 deletions(-)
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index afb1ede3fe..afa5fac152 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -345,15 +345,16 @@ OBJS-$(CONFIG_ADPCM_YAMAHA_ENCODER) += adpcm.o
# libavformat dependencies
OBJS-$(CONFIG_EAC3_DEMUXER) += ac3_parser.o ac3tab.o aac_ac3_parser.o
+OBJS-$(CONFIG_FLAC_MUXER) += flacdec.o
OBJS-$(CONFIG_GXF_DEMUXER) += mpeg12data.o
-OBJS-$(CONFIG_MATROSKA_AUDIO_MUXER) += xiph.o mpeg4audio.o
+OBJS-$(CONFIG_MATROSKA_AUDIO_MUXER) += xiph.o mpeg4audio.o flacdec.o
OBJS-$(CONFIG_MATROSKA_DEMUXER) += mpeg4audio.o
-OBJS-$(CONFIG_MATROSKA_MUXER) += xiph.o mpeg4audio.o
+OBJS-$(CONFIG_MATROSKA_MUXER) += xiph.o mpeg4audio.o flacdec.o
OBJS-$(CONFIG_MOV_DEMUXER) += mpeg4audio.o mpegaudiodata.o
OBJS-$(CONFIG_MPEGTS_MUXER) += mpegvideo.o
OBJS-$(CONFIG_NUT_MUXER) += mpegaudiodata.o
OBJS-$(CONFIG_OGG_DEMUXER) += flacdec.o
-OBJS-$(CONFIG_OGG_MUXER) += xiph.o
+OBJS-$(CONFIG_OGG_MUXER) += xiph.o flacdec.o
OBJS-$(CONFIG_RTP_MUXER) += mpegvideo.o
# external codec libraries
diff --git a/libavcodec/flac.h b/libavcodec/flac.h
index 9a4f820831..8af79f2bd8 100644
--- a/libavcodec/flac.h
+++ b/libavcodec/flac.h
@@ -42,6 +42,11 @@ enum {
FLAC_METADATA_TYPE_INVALID = 127
};
+enum FLACExtradataFormat {
+ FLAC_EXTRADATA_FORMAT_STREAMINFO = 0,
+ FLAC_EXTRADATA_FORMAT_FULL_HEADER = 1
+};
+
/**
* Data needed from the Streaminfo header for use by the raw FLAC demuxer
* and/or the FLAC decoder.
@@ -68,4 +73,15 @@ typedef struct FLACStreaminfo {
void ff_flac_parse_streaminfo(AVCodecContext *avctx, struct FLACStreaminfo *s,
const uint8_t *buffer);
+/**
+ * Validate the FLAC extradata.
+ * @param[in] avctx codec context containing the extradata.
+ * @param[out] format extradata format.
+ * @param[out] streaminfo_start pointer to start of 34-byte STREAMINFO data.
+ * @return 1 if valid, 0 if not valid.
+ */
+int ff_flac_is_extradata_valid(AVCodecContext *avctx,
+ enum FLACExtradataFormat *format,
+ uint8_t **streaminfo_start);
+
#endif /* AVCODEC_FLAC_H */
diff --git a/libavcodec/flacdec.c b/libavcodec/flacdec.c
index d6e0c8620f..42310b24a0 100644
--- a/libavcodec/flacdec.c
+++ b/libavcodec/flacdec.c
@@ -96,26 +96,55 @@ static int64_t get_utf8(GetBitContext *gb)
}
static void allocate_buffers(FLACContext *s);
-static int metadata_parse(FLACContext *s);
+
+int ff_flac_is_extradata_valid(AVCodecContext *avctx,
+ enum FLACExtradataFormat *format,
+ uint8_t **streaminfo_start)
+{
+ if (!avctx->extradata || avctx->extradata_size < FLAC_STREAMINFO_SIZE) {
+ av_log(avctx, AV_LOG_ERROR, "extradata NULL or too small.\n");
+ return 0;
+ }
+ if (AV_RL32(avctx->extradata) != MKTAG('f','L','a','C')) {
+ /* extradata contains STREAMINFO only */
+ if (avctx->extradata_size != FLAC_STREAMINFO_SIZE) {
+ av_log(avctx, AV_LOG_WARNING, "extradata contains %d bytes too many.\n",
+ FLAC_STREAMINFO_SIZE-avctx->extradata_size);
+ }
+ *format = FLAC_EXTRADATA_FORMAT_STREAMINFO;
+ *streaminfo_start = avctx->extradata;
+ } else {
+ if (avctx->extradata_size < 8+FLAC_STREAMINFO_SIZE) {
+ av_log(avctx, AV_LOG_ERROR, "extradata too small.\n");
+ return 0;
+ }
+ *format = FLAC_EXTRADATA_FORMAT_FULL_HEADER;
+ *streaminfo_start = &avctx->extradata[8];
+ }
+ return 1;
+}
static av_cold int flac_decode_init(AVCodecContext *avctx)
{
+ enum FLACExtradataFormat format;
+ uint8_t *streaminfo;
FLACContext *s = avctx->priv_data;
s->avctx = avctx;
avctx->sample_fmt = SAMPLE_FMT_S16;
- if (avctx->extradata_size > 4) {
+ /* for now, the raw FLAC header is allowed to be passed to the decoder as
+ frame data instead of extradata. */
+ if (!avctx->extradata)
+ return 0;
+
+ if (!ff_flac_is_extradata_valid(avctx, &format, &streaminfo))
+ return -1;
+
/* initialize based on the demuxer-supplied streamdata header */
- if (avctx->extradata_size == FLAC_STREAMINFO_SIZE) {
ff_flac_parse_streaminfo(avctx, (FLACStreaminfo *)s,
- avctx->extradata);
+ streaminfo);
allocate_buffers(s);
- } else {
- init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size*8);
- metadata_parse(s);
- }
- }
return 0;
}
diff --git a/libavformat/flacenc.c b/libavformat/flacenc.c
index 093a07a823..5595d76b7d 100644
--- a/libavformat/flacenc.c
+++ b/libavformat/flacenc.c
@@ -19,6 +19,7 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+#include "libavcodec/flac.h"
#include "avformat.h"
static int flac_write_header(struct AVFormatContext *s)
@@ -26,9 +27,15 @@ static int flac_write_header(struct AVFormatContext *s)
static const uint8_t header[8] = {
0x66, 0x4C, 0x61, 0x43, 0x80, 0x00, 0x00, 0x22
};
- uint8_t *streaminfo = s->streams[0]->codec->extradata;
+ AVCodecContext *codec = s->streams[0]->codec;
+ uint8_t *streaminfo;
int len = s->streams[0]->codec->extradata_size;
- if(streaminfo != NULL && len > 0) {
+ enum FLACExtradataFormat format;
+
+ if (!ff_flac_is_extradata_valid(codec, &format, &streaminfo))
+ return -1;
+
+ if (format == FLAC_EXTRADATA_FORMAT_STREAMINFO) {
put_buffer(s->pb, header, 8);
put_buffer(s->pb, streaminfo, len);
}
@@ -38,16 +45,22 @@ static int flac_write_header(struct AVFormatContext *s)
static int flac_write_trailer(struct AVFormatContext *s)
{
ByteIOContext *pb = s->pb;
- uint8_t *streaminfo = s->streams[0]->codec->extradata;
- int len = s->streams[0]->codec->extradata_size;
+ uint8_t *streaminfo;
+ enum FLACExtradataFormat format;
int64_t file_size;
- if (streaminfo && len > 0 && !url_is_streamed(s->pb)) {
+ if (!ff_flac_is_extradata_valid(s->streams[0]->codec, &format, &streaminfo))
+ return -1;
+
+ if (!url_is_streamed(pb)) {
+ /* rewrite the STREAMINFO header block data */
file_size = url_ftell(pb);
url_fseek(pb, 8, SEEK_SET);
- put_buffer(pb, streaminfo, len);
+ put_buffer(pb, streaminfo, FLAC_STREAMINFO_SIZE);
url_fseek(pb, file_size, SEEK_SET);
put_flush_packet(pb);
+ } else {
+ av_log(s, AV_LOG_WARNING, "unable to rewrite FLAC header.\n");
}
return 0;
}
diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index 44787be2d2..0b0adef1ba 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -28,6 +28,7 @@
#include "libavutil/md5.h"
#include "libavcodec/xiph.h"
#include "libavcodec/mpeg4audio.h"
+#include "libavcodec/flac.h"
typedef struct ebml_master {
int64_t pos; ///< absolute offset in the file where the master's elements start
@@ -420,23 +421,20 @@ static int put_xiph_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecCont
return 0;
}
-#define FLAC_STREAMINFO_SIZE 34
-
static int put_flac_codecpriv(AVFormatContext *s, ByteIOContext *pb, AVCodecContext *codec)
{
- // if the extradata_size is greater than FLAC_STREAMINFO_SIZE,
- // assume that it's in Matroska format already
- if (codec->extradata_size < FLAC_STREAMINFO_SIZE) {
+ uint8_t *streaminfo;
+ enum FLACExtradataFormat format;
+
+ if (!ff_flac_is_extradata_valid(codec, &format, &streaminfo)) {
av_log(s, AV_LOG_ERROR, "Invalid FLAC extradata\n");
return -1;
- } else if (codec->extradata_size == FLAC_STREAMINFO_SIZE) {
+ }
+ if (format == FLAC_EXTRADATA_FORMAT_STREAMINFO) {
// only the streaminfo packet
put_buffer(pb, "fLaC", 4);
put_byte(pb, 0x80);
put_be24(pb, FLAC_STREAMINFO_SIZE);
- } else if(memcmp("fLaC", codec->extradata, 4)) {
- av_log(s, AV_LOG_ERROR, "Invalid FLAC extradata\n");
- return -1;
}
put_buffer(pb, codec->extradata, codec->extradata_size);
return 0;
diff --git a/libavformat/oggenc.c b/libavformat/oggenc.c
index 4fdae05c8f..bbbee0a906 100644
--- a/libavformat/oggenc.c
+++ b/libavformat/oggenc.c
@@ -22,6 +22,7 @@
#include "libavutil/crc.h"
#include "libavcodec/xiph.h"
#include "libavcodec/bytestream.h"
+#include "libavcodec/flac.h"
#include "avformat.h"
#include "internal.h"
@@ -82,12 +83,14 @@ static int ogg_write_page(AVFormatContext *s, const uint8_t *data, int size,
return size;
}
-static int ogg_build_flac_headers(const uint8_t *extradata, int extradata_size,
+static int ogg_build_flac_headers(AVCodecContext *avctx,
OGGStreamContext *oggstream, int bitexact)
{
const char *vendor = bitexact ? "ffmpeg" : LIBAVFORMAT_IDENT;
+ enum FLACExtradataFormat format;
+ uint8_t *streaminfo;
uint8_t *p;
- if (extradata_size != 34)
+ if (!ff_flac_is_extradata_valid(avctx, &format, &streaminfo))
return -1;
oggstream->header_len[0] = 51;
oggstream->header[0] = av_mallocz(51); // per ogg flac specs
@@ -100,7 +103,7 @@ static int ogg_build_flac_headers(const uint8_t *extradata, int extradata_size,
bytestream_put_buffer(&p, "fLaC", 4);
bytestream_put_byte(&p, 0x00); // streaminfo
bytestream_put_be24(&p, 34);
- bytestream_put_buffer(&p, extradata, 34);
+ bytestream_put_buffer(&p, streaminfo, FLAC_STREAMINFO_SIZE);
oggstream->header_len[1] = 1+3+4+strlen(vendor)+4;
oggstream->header[1] = av_mallocz(oggstream->header_len[1]);
p = oggstream->header[1];
@@ -136,7 +139,7 @@ static int ogg_write_header(AVFormatContext *s)
oggstream = av_mallocz(sizeof(*oggstream));
st->priv_data = oggstream;
if (st->codec->codec_id == CODEC_ID_FLAC) {
- if (ogg_build_flac_headers(st->codec->extradata, st->codec->extradata_size,
+ if (ogg_build_flac_headers(st->codec,
oggstream, st->codec->flags & CODEC_FLAG_BITEXACT) < 0) {
av_log(s, AV_LOG_ERROR, "Extradata corrupted\n");
av_freep(&st->priv_data);