toq...@gmail.com:
> From: Wu Jianhua <toq...@outlook.com>
>
> Signed-off-by: Wu Jianhua <toq...@outlook.com>
> ---
> libavcodec/h274.c | 163 ++++++++++++++++++++++++++++++++++++++++++++++
> libavcodec/h274.h | 7 ++
> 2 files changed, 170 insertions(+)
>
> diff --git a/libavcodec/h274.c b/libavcodec/h274.c
> index 5709200322..9edc705042 100644
> --- a/libavcodec/h274.c
> +++ b/libavcodec/h274.c
> @@ -26,7 +26,11 @@
> */
>
> #include "libavutil/avassert.h"
> +#include "libavutil/bswap.h"
> +#include "libavutil/crc.h"
> #include "libavutil/imgutils.h"
> +#include "libavutil/md5.h"
> +#include "libavutil/mem.h"
>
> #include "h274.h"
>
> @@ -790,3 +794,162 @@ static const int8_t R64T[64][64] = {
> 17, -16, 15, -14, 13, -12, 11, -10, 9, -8, 7, -6, 4,
> -3, 2, -1,
> }
> };
> +
> +static int verify_plane_md5(struct AVMD5 *ctx,
> + const uint8_t *src, const int w, const int h, const int stride,
> + const uint8_t *expected)
> +{
> +#define MD5_SIZE 16
> + uint8_t md5[MD5_SIZE];
> + av_md5_init(ctx);
> + for (int j = 0; j < h; j++) {
> + av_md5_update(ctx, src, w);
> + src += stride;
> + }
> + av_md5_final(ctx, md5);
> +
> + if (memcmp(md5, expected, MD5_SIZE))
> + return AVERROR_INVALIDDATA;
> +
> + return 0;
> +}
> +
> +static int verify_plane_crc(const uint8_t *src, const int w, const int h,
> const int stride,
> + const uint8_t *expected)
> +{
> + uint32_t crc = 0x0F1D; // CRC-16-CCITT-AUG
> + const AVCRC *ctx = av_crc_get_table(AV_CRC_16_CCITT);
> +
> + for (int j = 0; j < h; j++) {
> + crc = av_crc(ctx, crc, src, w);
> + src += stride;
> + }
> + crc = av_bswap16(crc);
> +
> + if (memcmp(&crc, expected, sizeof(uint16_t)))
This seems endian-dependent (as are the other checks). Why don't you
simply pass the proper CRC as uint16_t/uint32_t parameter?
> + return AVERROR_INVALIDDATA;
> +
> + return 0;
> +}
> +
> +#define CAL_CHECKSUM(pixel) (checksum + ((pixel) ^ xor_mask))
> +static int verify_plane_checksum(const uint8_t *src, const int w, const int
> h, const int stride, const int ps,
> + const uint8_t *expected)
> +{
> + uint32_t checksum = 0;
> +
> + for (int y = 0; y < h; y++) {
> + for (int x = 0; x < w; x++) {
> + const int xor_mask = (x & 0xFF) ^ (y & 0xFF) ^ (x >> 8) ^ (y >>
> 8);
> + checksum = CAL_CHECKSUM(src[x << ps]);
> + if (ps)
> + checksum = CAL_CHECKSUM(src[(x << ps) + 1]);
Why don't you use checksum += instead of using checksum in the
CAL_CHECKSUM macro in a hardcoded manner?
> + }
> + src += stride;
> + }
> +
> + if (checksum != *(uint32_t*)expected)
> + return AVERROR_INVALIDDATA;
> +
> + return 0;
> +}
> +
> +static const uint8_t *get_plane_hash(const H274SEIPictureHash *h, const int
> plane)
> +{
> + if (!h->hash_type)
> + return h->md5[plane];
> + if (h->hash_type == 1)
> + return (uint8_t*)&h->crc[plane];
> + return (uint8_t*)&h->checksum[plane];
> +}
This function seems completely useless; you should better pass the
proper expected value to the functions directly (by value for non-md5).
> +
> +enum {
> + HASH_MD5SUM,
> + HASH_CRC,
> + HASH_CHECKSUM,
> + HASH_LAST = HASH_CHECKSUM,
> +};
> +
> +struct H274HashContext {
> + int type;
> + struct AVMD5 *ctx;
> +};
> +
> +int ff_h274_hash_freep(H274HashContext **ctx)
> +{
> + if (ctx && *ctx) {
Don't check for ctx. Passing a NULL to a freep-function is insane.
> + H274HashContext *c = *ctx;
> + if (c->ctx)
> + av_free(c->ctx);
> + av_freep(ctx);
> + }
> + return 0;
Why is this function returning anything?
> +}
> +
> +int ff_h274_hash_init(H274HashContext **ctx, const int type)
> +{
> + H274HashContext *c;
> +
> + if (type > HASH_LAST || !ctx)
> + return AVERROR(EINVAL);
> +
> + c = *ctx;
> + if (c) {
> + if (c->type != type) {
> + if (c->type == HASH_MD5SUM)
> + av_freep(&c->ctx);
> + c->type = type;
> + }
> + } else {
> + *ctx = c = av_mallocz(sizeof(H274HashContext));
Why is this separately allocated?
> + if (!c)
> + return AVERROR(ENOMEM);
> + c->type = type;
> + }
> +
> + if (type == HASH_MD5SUM && !c->ctx) {
> + c->ctx = av_md5_alloc();
> + if (!c->ctx)
> + return AVERROR(ENOMEM);
> + }
> +
> + return 0;
> +}
> +
> +int ff_h274_hash_verify(H274HashContext *c, const H274SEIPictureHash *hash,
> + const AVFrame *frame, const int coded_width, const int coded_height)
> +{
> + const AVPixFmtDescriptor *desc;
> + int err = 0;
> +
> + if (!c || !hash || !frame)
> + return AVERROR(EINVAL);
> +
> + if (c->type != hash->hash_type)
> + return AVERROR(EINVAL);
> +
> + desc = av_pix_fmt_desc_get(frame->format);
> + if (!desc)
> + return AVERROR(EINVAL);
> +
> + for (int i = 0; i < desc->nb_components; i++) {
> + const int w = i ? (coded_width >> desc->log2_chroma_w)
> : coded_width;
> + const int h = i ? (coded_height >> desc->log2_chroma_h)
> : coded_height;
> + const int ps = desc->comp[i].step - 1;
> + const uint8_t *expected = get_plane_hash(hash, i);
> + const uint8_t *src = frame->data[i];
> + const int stride = frame->linesize[i];
> +
> + if (c->type == HASH_MD5SUM)
> + err = verify_plane_md5(c->ctx, src, w << ps, h, stride,
> expected);
> + else if (c->type == HASH_CRC)
> + err = verify_plane_crc(src, w << ps, h, stride, expected);
> + else if (c->type == HASH_CHECKSUM)
> + err = verify_plane_checksum(src, w, h, stride, ps, expected);
> + if (err < 0)
> + goto fail;
> + }
> +
> +fail:
> + return err;
> +}
> diff --git a/libavcodec/h274.h b/libavcodec/h274.h
> index e1803edaf3..e2bb1aec55 100644
> --- a/libavcodec/h274.h
> +++ b/libavcodec/h274.h
> @@ -64,6 +64,8 @@ int ff_h274_apply_film_grain(AVFrame *out, const AVFrame
> *in,
> H274FilmGrainDatabase *db,
> const AVFilmGrainParams *params);
>
> +typedef struct H274HashContext H274HashContext;
> +
> typedef struct H274SEIPictureHash {
> int present;
> union {
> @@ -74,4 +76,9 @@ typedef struct H274SEIPictureHash {
> uint8_t hash_type;
> } H274SEIPictureHash;
>
> +int ff_h274_hash_init(H274HashContext **c, int type);
> +int ff_h274_hash_verify(H274HashContext *c, const H274SEIPictureHash *hash,
> + const AVFrame *frame, int coded_width, int coded_height);
> +int ff_h274_hash_freep(H274HashContext **c);
> +
> #endif /* AVCODEC_H274_H */
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