txd: port to bytestream2 API

Protects against overreads.

Signed-off-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
This commit is contained in:
Paul B Mahol 2012-03-12 17:37:02 +00:00 committed by Ronald S. Bultje
parent 85aded741e
commit 919f355438
3 changed files with 39 additions and 42 deletions

View File

@ -21,19 +21,19 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "libavcodec/bytestream.h"
#include "avcodec.h"
#include "s3tc.h"
static inline void dxt1_decode_pixels(const uint8_t *s, uint32_t *d,
static inline void dxt1_decode_pixels(GetByteContext *gb, uint32_t *d,
unsigned int qstride, unsigned int flag,
uint64_t alpha) {
unsigned int x, y, c0, c1, a = (!flag * 255u) << 24;
unsigned int rb0, rb1, rb2, rb3, g0, g1, g2, g3;
uint32_t colors[4], pixels;
c0 = AV_RL16(s);
c1 = AV_RL16(s+2);
c0 = bytestream2_get_le16(gb);
c1 = bytestream2_get_le16(gb);
rb0 = (c0<<3 | c0<<8) & 0xf800f8;
rb1 = (c1<<3 | c1<<8) & 0xf800f8;
@ -61,7 +61,7 @@ static inline void dxt1_decode_pixels(const uint8_t *s, uint32_t *d,
colors[2] = rb2 + g2 + a;
pixels = AV_RL32(s+4);
pixels = bytestream2_get_le32(gb);
for (y=0; y<4; y++) {
for (x=0; x<4; x++) {
a = (alpha & 0x0f) << 28;
@ -74,24 +74,24 @@ static inline void dxt1_decode_pixels(const uint8_t *s, uint32_t *d,
}
}
void ff_decode_dxt1(const uint8_t *s, uint8_t *dst,
void ff_decode_dxt1(GetByteContext *gb, uint8_t *dst,
const unsigned int w, const unsigned int h,
const unsigned int stride) {
unsigned int bx, by, qstride = stride/4;
uint32_t *d = (uint32_t *) dst;
for (by=0; by < h/4; by++, d += stride-w)
for (bx=0; bx < w/4; bx++, s+=8, d+=4)
dxt1_decode_pixels(s, d, qstride, 0, 0LL);
for (bx = 0; bx < w / 4; bx++, d += 4)
dxt1_decode_pixels(gb, d, qstride, 0, 0LL);
}
void ff_decode_dxt3(const uint8_t *s, uint8_t *dst,
void ff_decode_dxt3(GetByteContext *gb, uint8_t *dst,
const unsigned int w, const unsigned int h,
const unsigned int stride) {
unsigned int bx, by, qstride = stride/4;
uint32_t *d = (uint32_t *) dst;
for (by=0; by < h/4; by++, d += stride-w)
for (bx=0; bx < w/4; bx++, s+=16, d+=4)
dxt1_decode_pixels(s+8, d, qstride, 1, AV_RL64(s));
for (bx = 0; bx < w / 4; bx++, d += 4)
dxt1_decode_pixels(gb, d, qstride, 1, bytestream2_get_le64(gb));
}

View File

@ -29,24 +29,24 @@
/**
* Decode DXT1 encoded data to RGB32
* @param src source buffer, has to be aligned on a 4-byte boundary
* @param gb GetByteContext
* @param dst destination buffer
* @param w width of output image
* @param h height of output image
* @param stride line size of output image
*/
void ff_decode_dxt1(const uint8_t *src, uint8_t *dst,
void ff_decode_dxt1(GetByteContext *gb, uint8_t *dst,
const unsigned int w, const unsigned int h,
const unsigned int stride);
/**
* Decode DXT3 encoded data to RGB32
* @param src source buffer, has to be aligned on a 4-byte boundary
* @param gb GetByteContext
* @param dst destination buffer
* @param w width of output image
* @param h height of output image
* @param stride line size of output image
*/
void ff_decode_dxt3(const uint8_t *src, uint8_t *dst,
void ff_decode_dxt3(GetByteContext *gb, uint8_t *dst,
const unsigned int w, const unsigned int h,
const unsigned int stride);

View File

@ -24,6 +24,7 @@
#include "libavutil/intreadwrite.h"
#include "libavutil/imgutils.h"
#include "avcodec.h"
#include "bytestream.h"
#include "s3tc.h"
typedef struct TXDContext {
@ -41,25 +42,25 @@ static av_cold int txd_init(AVCodecContext *avctx) {
static int txd_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
AVPacket *avpkt) {
const uint8_t *buf = avpkt->data;
TXDContext * const s = avctx->priv_data;
GetByteContext gb;
AVFrame *picture = data;
AVFrame * const p = &s->picture;
unsigned int version, w, h, d3d_format, depth, stride, mipmap_count, flags;
unsigned int y, v;
uint8_t *ptr;
const uint8_t *cur = buf;
const uint32_t *palette = (const uint32_t *)(cur + 88);
uint32_t *pal;
version = AV_RL32(cur);
d3d_format = AV_RL32(cur+76);
w = AV_RL16(cur+80);
h = AV_RL16(cur+82);
depth = AV_RL8 (cur+84);
mipmap_count = AV_RL8 (cur+85);
flags = AV_RL8 (cur+87);
cur += 92;
bytestream2_init(&gb, avpkt->data, avpkt->size);
version = bytestream2_get_le32(&gb);
bytestream2_skip(&gb, 72);
d3d_format = bytestream2_get_le32(&gb);
w = bytestream2_get_le16(&gb);
h = bytestream2_get_le16(&gb);
depth = bytestream2_get_byte(&gb);
mipmap_count = bytestream2_get_byte(&gb);
bytestream2_skip(&gb, 1);
flags = bytestream2_get_byte(&gb);
if (version < 8 || version > 9) {
av_log(avctx, AV_LOG_ERROR, "texture data version %i is unsupported\n",
@ -69,10 +70,9 @@ static int txd_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
if (depth == 8) {
avctx->pix_fmt = PIX_FMT_PAL8;
cur += 1024;
} else if (depth == 16 || depth == 32)
} else if (depth == 16 || depth == 32) {
avctx->pix_fmt = PIX_FMT_RGB32;
else {
} else {
av_log(avctx, AV_LOG_ERROR, "depth of %i is unsupported\n", depth);
return -1;
}
@ -97,24 +97,25 @@ static int txd_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
if (depth == 8) {
pal = (uint32_t *) p->data[1];
for (y = 0; y < 256; y++) {
v = AV_RB32(palette+y);
v = bytestream2_get_be32(&gb);
pal[y] = (v >> 8) + (v << 24);
}
bytestream2_skip(&gb, 4);
for (y=0; y<h; y++) {
memcpy(ptr, cur, w);
bytestream2_get_buffer(&gb, ptr, w);
ptr += stride;
cur += w;
}
} else if (depth == 16) {
bytestream2_skip(&gb, 4);
switch (d3d_format) {
case 0:
if (!(flags & 1))
goto unsupported;
case FF_S3TC_DXT1:
ff_decode_dxt1(cur, ptr, w, h, stride);
ff_decode_dxt1(&gb, ptr, w, h, stride);
break;
case FF_S3TC_DXT3:
ff_decode_dxt3(cur, ptr, w, h, stride);
ff_decode_dxt3(&gb, ptr, w, h, stride);
break;
default:
goto unsupported;
@ -124,9 +125,8 @@ static int txd_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
case 0x15:
case 0x16:
for (y=0; y<h; y++) {
memcpy(ptr, cur, w*4);
bytestream2_get_buffer(&gb, ptr, w * 4);
ptr += stride;
cur += w*4;
}
break;
default:
@ -134,13 +134,10 @@ static int txd_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
}
}
for (; mipmap_count > 1; mipmap_count--)
cur += AV_RL32(cur) + 4;
*picture = s->picture;
*data_size = sizeof(AVPicture);
return cur - buf;
return avpkt->size;
unsupported:
av_log(avctx, AV_LOG_ERROR, "unsupported d3d format (%08x)\n", d3d_format);