Skip to content

F
ffmpeg.wasm-core
Commit 29b0d94b authored by Paul B Mahol's avatar Paul B Mahol Committed by Ronald S. Bultje
Browse files
Options

dfa: convert to bytestream2 API 

Protects from overreads.
Signed-off-by: 's avatarPaul B Mahol <onemda@gmail.com>
Signed-off-by: 's avatarRonald S. Bultje <rsbultje@gmail.com>
parent 015da6e3
Hide whitespace changes
Inline Side-by-side
Showing with 74 additions and 89 deletions
libavcodec/dfa.c
View file @ 29b0d94b
......@@ -21,7 +21,6 @@
*/
#include "avcodec.h"
#include "libavutil/intreadwrite.h"
#include "bytestream.h"
#include "libavutil/lzo.h" // for av_memcpy_backptr
......@@ -45,19 +44,16 @@ static av_cold int dfa_decode_init(AVCodecContext *avctx)
return 0;
}
static int decode_copy(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_copy(GetByteContext *gb, uint8_t *frame, int width, int height)
{
const int size = width * height;
if (src_end - src < size)
if (bytestream2_get_buffer(gb, frame, size) != size)
return -1;
bytestream_get_buffer(&src, frame, size);
return 0;
}
static int decode_tsw1(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_tsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
{
const uint8_t *frame_start = frame;
const uint8_t *frame_end = frame + width * height;
......@@ -65,22 +61,22 @@ static int decode_tsw1(uint8_t *frame, int width, int height,
int v, count, segments;
unsigned offset;
segments = bytestream_get_le32(&src);
offset = bytestream_get_le32(&src);
segments = bytestream2_get_le32(gb);
offset = bytestream2_get_le32(gb);
if (frame_end - frame <= offset)
return -1;
frame += offset;
while (segments--) {
if (bytestream2_get_bytes_left(gb) < 2)
return -1;
if (mask == 0x10000) {
if (src >= src_end)
return -1;
bitbuf = bytestream_get_le16(&src);
bitbuf = bytestream2_get_le16u(gb);
mask = 1;
}
if (src_end - src < 2 || frame_end - frame < 2)
if (frame_end - frame < 2)
return -1;
if (bitbuf & mask) {
v = bytestream_get_le16(&src);
v = bytestream2_get_le16(gb);
offset = (v & 0x1FFF) << 1;
count = ((v >> 13) + 2) << 1;
if (frame - frame_start < offset || frame_end - frame < count)
......@@ -88,8 +84,8 @@ static int decode_tsw1(uint8_t *frame, int width, int height,
av_memcpy_backptr(frame, offset, count);
frame += count;
} else {
*frame++ = *src++;
*frame++ = *src++;
*frame++ = bytestream2_get_byte(gb);
*frame++ = bytestream2_get_byte(gb);
}
mask <<= 1;
}
......@@ -97,26 +93,25 @@ static int decode_tsw1(uint8_t *frame, int width, int height,
return 0;
}
static int decode_dsw1(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_dsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
{
const uint8_t *frame_start = frame;
const uint8_t *frame_end = frame + width * height;
int mask = 0x10000, bitbuf = 0;
int v, offset, count, segments;
segments = bytestream_get_le16(&src);
segments = bytestream2_get_le16(gb);
while (segments--) {
if (bytestream2_get_bytes_left(gb) < 2)
return -1;
if (mask == 0x10000) {
if (src >= src_end)
return -1;
bitbuf = bytestream_get_le16(&src);
bitbuf = bytestream2_get_le16u(gb);
mask = 1;
}
if (src_end - src < 2 || frame_end - frame < 2)
if (frame_end - frame < 2)
return -1;
if (bitbuf & mask) {
v = bytestream_get_le16(&src);
v = bytestream2_get_le16(gb);
offset = (v & 0x1FFF) << 1;
count = ((v >> 13) + 2) << 1;
if (frame - frame_start < offset || frame_end - frame < count)
......@@ -126,10 +121,10 @@ static int decode_dsw1(uint8_t *frame, int width, int height,
frame[v] = frame[v - offset];
frame += count;
} else if (bitbuf & (mask << 1)) {
frame += bytestream_get_le16(&src);
frame += bytestream2_get_le16(gb);
} else {
*frame++ = *src++;
*frame++ = *src++;
*frame++ = bytestream2_get_byte(gb);
*frame++ = bytestream2_get_byte(gb);
}
mask <<= 2;
}
......@@ -137,26 +132,25 @@ static int decode_dsw1(uint8_t *frame, int width, int height,
return 0;
}
static int decode_dds1(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height)
{
const uint8_t *frame_start = frame;
const uint8_t *frame_end = frame + width * height;
int mask = 0x10000, bitbuf = 0;
int i, v, offset, count, segments;
segments = bytestream_get_le16(&src);
segments = bytestream2_get_le16(gb);
while (segments--) {
if (bytestream2_get_bytes_left(gb) < 2)
return -1;
if (mask == 0x10000) {
if (src >= src_end)
return -1;
bitbuf = bytestream_get_le16(&src);
bitbuf = bytestream2_get_le16u(gb);
mask = 1;
}
if (src_end - src < 2 || frame_end - frame < 2)
if (frame_end - frame < 2)
return -1;
if (bitbuf & mask) {
v = bytestream_get_le16(&src);
v = bytestream2_get_le16(gb);
offset = (v & 0x1FFF) << 2;
count = ((v >> 13) + 2) << 1;
if (frame - frame_start < offset || frame_end - frame < count*2 + width)
......@@ -168,13 +162,13 @@ static int decode_dds1(uint8_t *frame, int width, int height,
frame += 2;
}
} else if (bitbuf & (mask << 1)) {
frame += bytestream_get_le16(&src) * 2;
frame += bytestream2_get_le16(gb) * 2;
} else {
frame[0] = frame[1] =
frame[width] = frame[width + 1] = *src++;
frame[width] = frame[width + 1] = bytestream2_get_byte(gb);
frame += 2;
frame[0] = frame[1] =
frame[width] = frame[width + 1] = *src++;
frame[width] = frame[width + 1] = bytestream2_get_byte(gb);
frame += 2;
}
mask <<= 2;
......@@ -183,40 +177,40 @@ static int decode_dds1(uint8_t *frame, int width, int height,
return 0;
}
static int decode_bdlt(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
{
uint8_t *line_ptr;
int count, lines, segments;
count = bytestream_get_le16(&src);
count = bytestream2_get_le16(gb);
if (count >= height)
return -1;
frame += width * count;
lines = bytestream_get_le16(&src);
if (count + lines > height || src >= src_end)
lines = bytestream2_get_le16(gb);
if (count + lines > height)
return -1;
while (lines--) {
if (bytestream2_get_bytes_left(gb) < 1)
return -1;
line_ptr = frame;
frame += width;
segments = *src++;
segments = bytestream2_get_byteu(gb);
while (segments--) {
if (src_end - src < 3)
if (frame - line_ptr <= bytestream2_peek_byte(gb))
return -1;
if (frame - line_ptr <= *src)
return -1;
line_ptr += *src++;
count = (int8_t)*src++;
line_ptr += bytestream2_get_byte(gb);
count = (int8_t)bytestream2_get_byte(gb);
if (count >= 0) {
if (frame - line_ptr < count || src_end - src < count)
if (frame - line_ptr < count)
return -1;
if (bytestream2_get_buffer(gb, line_ptr, count) != count)
return -1;
bytestream_get_buffer(&src, line_ptr, count);
} else {
count = -count;
if (frame - line_ptr < count || src >= src_end)
if (frame - line_ptr < count)
return -1;
memset(line_ptr, *src++, count);
memset(line_ptr, bytestream2_get_byte(gb), count);
}
line_ptr += count;
}
......@@ -225,49 +219,49 @@ static int decode_bdlt(uint8_t *frame, int width, int height,
return 0;
}
static int decode_wdlt(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
{
const uint8_t *frame_end = frame + width * height;
uint8_t *line_ptr;
int count, i, v, lines, segments;
lines = bytestream_get_le16(&src);
if (lines > height || src >= src_end)
lines = bytestream2_get_le16(gb);
if (lines > height)
return -1;
while (lines--) {
segments = bytestream_get_le16(&src);
if (bytestream2_get_bytes_left(gb) < 2)
return -1;
segments = bytestream2_get_le16u(gb);
while ((segments & 0xC000) == 0xC000) {
unsigned delta = -((int16_t)segments * width);
if (frame_end - frame <= delta)
return -1;
frame += delta;
segments = bytestream_get_le16(&src);
segments = bytestream2_get_le16(gb);
}
if (segments & 0x8000) {
frame[width - 1] = segments & 0xFF;
segments = bytestream_get_le16(&src);
segments = bytestream2_get_le16(gb);
}
line_ptr = frame;
frame += width;
while (segments--) {
if (src_end - src < 2)
return -1;
if (frame - line_ptr <= *src)
if (frame - line_ptr <= bytestream2_peek_byte(gb))
return -1;
line_ptr += *src++;
count = (int8_t)*src++;
line_ptr += bytestream2_get_byte(gb);
count = (int8_t)bytestream2_get_byte(gb);
if (count >= 0) {
if (frame - line_ptr < count*2 || src_end - src < count*2)
if (frame - line_ptr < count * 2)
return -1;
if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2)
return -1;
bytestream_get_buffer(&src, line_ptr, count*2);
line_ptr += count * 2;
} else {
count = -count;
if (frame - line_ptr < count*2 || src_end - src < 2)
if (frame - line_ptr < count * 2)
return -1;
v = bytestream_get_le16(&src);
v = bytestream2_get_le16(gb);
for (i = 0; i < count; i++)
bytestream_put_le16(&line_ptr, v);
}
......@@ -277,22 +271,19 @@ static int decode_wdlt(uint8_t *frame, int width, int height,
return 0;
}
static int decode_unk6(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_unk6(GetByteContext *gb, uint8_t *frame, int width, int height)
{
return -1;
}
static int decode_blck(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end)
static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height)
{
memset(frame, 0, width * height);
return 0;
}
typedef int (*chunk_decoder)(uint8_t *frame, int width, int height,
const uint8_t *src, const uint8_t *src_end);
typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height);
static const chunk_decoder decoder[8] = {
decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,
......@@ -308,9 +299,8 @@ static int dfa_decode_frame(AVCodecContext *avctx,
AVPacket *avpkt)
{
DfaContext *s = avctx->priv_data;
GetByteContext gb;
const uint8_t *buf = avpkt->data;
const uint8_t *buf_end = avpkt->data + avpkt->size;
const uint8_t *tmp_buf;
uint32_t chunk_type, chunk_size;
uint8_t *dst;
int ret;
......@@ -324,27 +314,22 @@ static int dfa_decode_frame(AVCodecContext *avctx,
return ret;
}
while (buf < buf_end) {
chunk_size = AV_RL32(buf + 4);
chunk_type = AV_RL32(buf + 8);
buf += 12;
if (buf_end - buf < chunk_size) {
av_log(avctx, AV_LOG_ERROR, "Chunk size is too big (%d bytes)\n", chunk_size);
return -1;
}
bytestream2_init(&gb, avpkt->data, avpkt->size);
while (bytestream2_get_bytes_left(&gb) > 0) {
bytestream2_skip(&gb, 4);
chunk_size = bytestream2_get_le32(&gb);
chunk_type = bytestream2_get_le32(&gb);
if (!chunk_type)
break;
if (chunk_type == 1) {
pal_elems = FFMIN(chunk_size / 3, 256);
tmp_buf = buf;
for (i = 0; i < pal_elems; i++) {
s->pal[i] = bytestream_get_be24(&tmp_buf) << 2;
s->pal[i] = bytestream2_get_be24(&gb) << 2;
s->pal[i] |= (s->pal[i] >> 6) & 0x333;
}
s->pic.palette_has_changed = 1;
} else if (chunk_type <= 9) {
if (decoder[chunk_type - 2](s->frame_buf, avctx->width, avctx->height,
buf, buf + chunk_size)) {
if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) {
av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",
chunk_name[chunk_type - 2]);
return -1;
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment