On 2021-12-22 06:43 pm, Nicolas George wrote:
Gyan Doshi (12021-12-22):Helper function to check if stored box size is correct and looks to be fully available. --- libavformat/mov.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/libavformat/mov.c b/libavformat/mov.c index 2aed6e80ef..7de95b7ab0 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -80,6 +80,40 @@ static int mov_read_mfra(MOVContext *c, AVIOContext *f); static int64_t add_ctts_entry(MOVCtts** ctts_data, unsigned int* ctts_count, unsigned int* allocated_size, int count, int duration);+/** Check if the box size meets the requirements passed in limit and constraint_type.+ * If input avio_size is valid, it checks if box size appears to be available. + * + * constraint_type may be + * 0 if the box size has to be exactly equal to limit + * -1 if the box size has to be at most limit + * 1 if the box size has to be at least limit + * + * Returns 0 if size meets requirements. + */ +static int validate_box_size(MOVContext *c, MOVAtom atom, AVIOContext *pb, + int64_t pos, int64_t limit, int constraint_type) +{ + int size_fit; + int64_t input_size = avio_size(pb); + + if (input_size > 0 && + input_size - pos < atom.size) { + av_log(c->fc, AV_LOG_ERROR, "Box %s is truncated\n", av_fourcc2str(atom.type)); + return AVERROR_INVALIDDATA; + } + + if (FFABS(constraint_type) > 1) + return AVERROR_BUG;av_assert() whould have been the right choice here.
Will change.
+ + switch(constraint_type) { + case 0: size_fit = atom.size == limit; break; + case -1: size_fit = atom.size <= limit; break; + case 1: size_fit = atom.size >= limit; break;This code is unused, AFAICS. Not a good idea.
I'll call this function in other box readers. Their requirements are different.
That's why I made the check a separate function. Regards, Gyan _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
