[FFmpeg-devel] [PATCH 1/2] avcodec/wrapped_avframe: implement wrapped_avframe decoder

[wm4]

On Mon, 9 Nov 2015 08:03:54 -0800
Muhammad Faiz <mfcc64 at gmail.com> wrote:

> From 4dcbda2e585404d2d79d5afcdc13fcb699f6f158 Mon Sep 17 00:00:00 2001
> From: Muhammad Faiz <mfcc64 at gmail.com>
> Date: Mon, 9 Nov 2015 15:55:13 +0700
> Subject: [PATCH 1/2] avcodec/wrapped_avframe: implement wrapped_avframe
>  decoder
> 
> fix ticket #4985
> for use in avdevice/lavfi
> ---
>  libavcodec/Makefile          |  1 +
>  libavcodec/allcodecs.c       |  2 +-
>  libavcodec/version.h         |  2 +-
>  libavcodec/wrapped_avframe.c | 32 ++++++++++++++++++++++++++++++++
>  4 files changed, 35 insertions(+), 2 deletions(-)
> 
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index 68a573f..c60d512 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -577,6 +577,7 @@ OBJS-$(CONFIG_WMV2_ENCODER)            += wmv2enc.o wmv2.o \
>                                            msmpeg4.o msmpeg4enc.o msmpeg4data.o
>  OBJS-$(CONFIG_WNV1_DECODER)            += wnv1.o
>  OBJS-$(CONFIG_WS_SND1_DECODER)         += ws-snd1.o
> +OBJS-$(CONFIG_WRAPPED_AVFRAME_DECODER) += wrapped_avframe.o
>  OBJS-$(CONFIG_WRAPPED_AVFRAME_ENCODER) += wrapped_avframe.o
>  OBJS-$(CONFIG_XAN_DPCM_DECODER)        += dpcm.o
>  OBJS-$(CONFIG_XAN_WC3_DECODER)         += xan.o
> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
> index 9f60d7c..3260927 100644
> --- a/libavcodec/allcodecs.c
> +++ b/libavcodec/allcodecs.c
> @@ -342,7 +342,7 @@ void avcodec_register_all(void)
>      REGISTER_DECODER(VP9,               vp9);
>      REGISTER_DECODER(VQA,               vqa);
>      REGISTER_DECODER(WEBP,              webp);
> -    REGISTER_ENCODER(WRAPPED_AVFRAME,   wrapped_avframe);
> +    REGISTER_ENCDEC (WRAPPED_AVFRAME,   wrapped_avframe);
>      REGISTER_ENCDEC (WMV1,              wmv1);
>      REGISTER_ENCDEC (WMV2,              wmv2);
>      REGISTER_DECODER(WMV3,              wmv3);
> diff --git a/libavcodec/version.h b/libavcodec/version.h
> index 1e21f15..5eecf5b 100644
> --- a/libavcodec/version.h
> +++ b/libavcodec/version.h
> @@ -29,7 +29,7 @@
>  #include "libavutil/version.h"
>  
>  #define LIBAVCODEC_VERSION_MAJOR  57
> -#define LIBAVCODEC_VERSION_MINOR  15
> +#define LIBAVCODEC_VERSION_MINOR  16
>  #define LIBAVCODEC_VERSION_MICRO 100
>  
>  #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
> diff --git a/libavcodec/wrapped_avframe.c b/libavcodec/wrapped_avframe.c
> index 13c8d8a..185a1a2 100644
> --- a/libavcodec/wrapped_avframe.c
> +++ b/libavcodec/wrapped_avframe.c
> @@ -32,6 +32,8 @@
>  #include "libavutil/buffer.h"
>  #include "libavutil/pixdesc.h"
>  
> +#if CONFIG_WRAPPED_AVFRAME_ENCODER
> +
>  static void wrapped_avframe_release_buffer(void *unused, uint8_t *data)
>  {
>      AVFrame *frame = (AVFrame *)data;
> @@ -71,3 +73,33 @@ AVCodec ff_wrapped_avframe_encoder = {
>      .encode2        = wrapped_avframe_encode,
>      .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
>  };
> +
> +#endif
> +
> +#if CONFIG_WRAPPED_AVFRAME_DECODER
> +
> +static int wrapped_avframe_decode(AVCodecContext *avctx, void *data,
> +                                  int *got_frame, AVPacket *avpkt)
> +{
> +    int ret;
> +
> +    if (avpkt->size != sizeof(AVFrame))
> +        return AVERROR(EINVAL);
> +
> +    if ((ret = av_frame_ref((AVFrame *) data, (AVFrame *) avpkt->data)) < 0)
> +        return ret;
> +
> +    *got_frame = 1;
> +    return avpkt->size;
> +}
> +
> +AVCodec ff_wrapped_avframe_decoder = {
> +    .name           = "wrapped_avframe",
> +    .long_name      = NULL_IF_CONFIG_SMALL("AVFrame to AVPacket passthrough"),
> +    .type           = AVMEDIA_TYPE_VIDEO,
> +    .id             = AV_CODEC_ID_WRAPPED_AVFRAME,
> +    .decode         = wrapped_avframe_decode,
> +    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
> +};
> +
> +#endif

This is very dangerous. You get potentially security relevant bad
behavior if you get anyone to force a demuxer/decoder on an untrusted
input file.