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/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavcodec/avcodec.h"
#include "libavcodec/bytestream.h"
#include "libavformat/avformat.h"
typedef struct IOContext {
int64_t pos;
int64_t filesize;
uint8_t *fuzz;
int fuzz_size;
} IOContext;
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
static void error(const char *err)
{
fprintf(stderr, "%s", err);
exit(1);
}
static int io_read(void *opaque, uint8_t *buf, int buf_size)
{
IOContext *c = opaque;
int size = FFMIN(buf_size, c->fuzz_size);
if (!c->fuzz_size) {
c->filesize = FFMIN(c->pos, c->filesize);
return AVERROR_EOF;
}
if (c->pos > INT64_MAX - size)
return AVERROR(EIO);
memcpy(buf, c->fuzz, size);
c->fuzz += size;
c->fuzz_size -= size;
c->pos += size;
c->filesize = FFMAX(c->filesize, c->pos);
return size;
}
static int64_t io_seek(void *opaque, int64_t offset, int whence)
{
IOContext *c = opaque;
if (whence == SEEK_CUR) {
if (offset > INT64_MAX - c->pos)
return -1;
offset += c->pos;
} else if (whence == SEEK_END) {
if (offset > INT64_MAX - c->filesize)
return -1;
offset += c->filesize;
} else if (whence == AVSEEK_SIZE) {
return c->filesize;
}
if (offset < 0 || offset > c->filesize)
return -1;
if (IO_FLAT) {
c->fuzz += offset - c->pos;
c->fuzz_size -= offset - c->pos;
}
c->pos = offset;
return 0;
}
// Ensure we don't loop forever
const uint32_t maxiteration = 8096;
const int maxblocks= 100000;
static const uint64_t FUZZ_TAG = 0x4741542D5A5A5546ULL;
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
const uint64_t fuzz_tag = FUZZ_TAG;
uint32_t it = 0;
AVFormatContext *avfmt = avformat_alloc_context();
AVPacket pkt;
char filename[1025] = {0};
AVIOContext *fuzzed_pb = NULL;
uint8_t *io_buffer;
int io_buffer_size = 32768;
int64_t filesize = size;
IOContext opaque;
static int c;
int seekable = 0;
int ret;
AVInputFormat *fmt = NULL;
#ifdef FFMPEG_DEMUXER
#define DEMUXER_SYMBOL0(DEMUXER) ff_##DEMUXER##_demuxer
#define DEMUXER_SYMBOL(DEMUXER) DEMUXER_SYMBOL0(DEMUXER)
extern AVInputFormat DEMUXER_SYMBOL(FFMPEG_DEMUXER);
fmt = &DEMUXER_SYMBOL(FFMPEG_DEMUXER);
#endif
if (!c) {
av_log_set_level(AV_LOG_PANIC);
c=1;
}
if (!avfmt)
error("Failed avformat_alloc_context()");
if (IO_FLAT) {
seekable = 1;
io_buffer_size = size;
} else if (size > 2048) {
int flags;
char extension[64];
GetByteContext gbc;
memcpy (filename, data + size - 1024, 1024);
bytestream2_init(&gbc, data + size - 2048, 1024);
size -= 2048;
io_buffer_size = bytestream2_get_le32(&gbc) & 0xFFFFFFF;
flags = bytestream2_get_byte(&gbc);
seekable = flags & 1;
filesize = bytestream2_get_le64(&gbc) & 0x7FFFFFFFFFFFFFFF;
if ((flags & 2) && strlen(filename) < sizeof(filename) / 2) {
const AVInputFormat *avif = NULL;
void *avif_iter = NULL;
int avif_count = 0;
while ((avif = av_demuxer_iterate(&avif_iter))) {
if (avif->extensions)
avif_count ++;
}
avif_count = bytestream2_get_le32(&gbc) % avif_count;
avif_iter = NULL;
while ((avif = av_demuxer_iterate(&avif_iter))) {
if (avif->extensions)
if (!avif_count--)
break;
}
av_strlcpy(extension, avif->extensions, sizeof(extension));
if (strchr(extension, ','))
*strchr(extension, ',') = 0;
av_strlcatf(filename, sizeof(filename), ".%s", extension);
}
}
if (!io_buffer_size || size / io_buffer_size > maxblocks)
io_buffer_size = size;
io_buffer = av_malloc(io_buffer_size);
if (!io_buffer)
error("Failed to allocate io_buffer");
opaque.filesize = filesize;
opaque.pos = 0;
opaque.fuzz = data;
opaque.fuzz_size= size;
fuzzed_pb = avio_alloc_context(io_buffer, io_buffer_size, 0, &opaque,
io_read, NULL, seekable ? io_seek : NULL);
if (!fuzzed_pb)
error("avio_alloc_context failed");
avfmt->pb = fuzzed_pb;
ret = avformat_open_input(&avfmt, filename, fmt, NULL);
if (ret < 0) {
av_freep(&fuzzed_pb->buffer);
av_freep(&fuzzed_pb);
avformat_free_context(avfmt);
return 0;
}
ret = avformat_find_stream_info(avfmt, NULL);
av_init_packet(&pkt);
//TODO, test seeking
for(it = 0; it < maxiteration; it++) {
ret = av_read_frame(avfmt, &pkt);
if (ret < 0)
break;
av_packet_unref(&pkt);
}
av_freep(&fuzzed_pb->buffer);
avio_context_free(&fuzzed_pb);
avformat_close_input(&avfmt);
return 0;
}
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