[FFmpeg-cvslog] tiff: port to bytestream2
Paul B Mahol
git at videolan.org
Tue Jul 17 03:35:04 CEST 2012
ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Sun Jul 15 20:58:13 2012 +0000| [1ec83d9a9e472f485897ac92bad9631d551a8c5b] | committer: Paul B Mahol
tiff: port to bytestream2
Prevents out of array reads.
Signed-off-by: Paul B Mahol <onemda at gmail.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=1ec83d9a9e472f485897ac92bad9631d551a8c5b
---
libavcodec/tiff.c | 218 +++++++++++++++++++++++++++--------------------------
1 file changed, 112 insertions(+), 106 deletions(-)
diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index 88f5238..7547406 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -25,6 +25,7 @@
*/
#include "avcodec.h"
+#include "bytestream.h"
#if CONFIG_ZLIB
#include <zlib.h>
#endif
@@ -40,6 +41,7 @@
typedef struct TiffContext {
AVCodecContext *avctx;
AVFrame picture;
+ GetByteContext gb;
int width, height;
unsigned int bpp, bppcount;
@@ -54,42 +56,37 @@ typedef struct TiffContext {
int strips, rps, sstype;
int sot;
- const uint8_t *stripdata;
- const uint8_t *stripsizes;
- int stripsize, stripoff;
+ int stripsizesoff, stripsize, stripoff, strippos;
LZWState *lzw;
int geotag_count;
TiffGeoTag *geotags;
} TiffContext;
-static unsigned tget_short(const uint8_t **p, int le)
+static unsigned tget_short(GetByteContext *gb, int le)
{
- unsigned v = le ? AV_RL16(*p) : AV_RB16(*p);
- *p += 2;
+ unsigned v = le ? bytestream2_get_le16(gb) : bytestream2_get_be16(gb);
return v;
}
-static unsigned tget_long(const uint8_t **p, int le)
+static unsigned tget_long(GetByteContext *gb, int le)
{
- unsigned v = le ? AV_RL32(*p) : AV_RB32(*p);
- *p += 4;
+ unsigned v = le ? bytestream2_get_le32(gb) : bytestream2_get_be32(gb);
return v;
}
-static double tget_double(const uint8_t **p, int le)
+static double tget_double(GetByteContext *gb, int le)
{
- av_alias64 i = { .u64 = le ? AV_RL64(*p) : AV_RB64(*p)};
- *p += 8;
+ av_alias64 i = { .u64 = le ? bytestream2_get_le64(gb) : bytestream2_get_be64(gb)};
return i.f64;
}
-static unsigned tget(const uint8_t **p, int type, int le)
+static unsigned tget(GetByteContext *gb, int type, int le)
{
switch (type) {
- case TIFF_BYTE : return *(*p)++;
- case TIFF_SHORT: return tget_short(p, le);
- case TIFF_LONG : return tget_long(p, le);
+ case TIFF_BYTE : return bytestream2_get_byte(gb);
+ case TIFF_SHORT: return tget_short(gb, le);
+ case TIFF_LONG : return tget_long(gb, le);
default : return UINT_MAX;
}
}
@@ -223,7 +220,7 @@ static char *doubles2str(double *dp, int count, const char *sep)
return ap0;
}
-static char *shorts2str(int *sp, int count, const char *sep)
+static char *shorts2str(int16_t *sp, int count, const char *sep)
{
int i;
char *ap, *ap0;
@@ -241,18 +238,23 @@ static char *shorts2str(int *sp, int count, const char *sep)
return ap0;
}
-static int add_doubles_metadata(const uint8_t **buf, int count,
+static int add_doubles_metadata(int count,
const char *name, const char *sep,
TiffContext *s)
{
char *ap;
int i;
- double *dp = av_malloc(count * sizeof(double));
+ double *dp;
+
+ if (bytestream2_get_bytes_left(&s->gb) < count * sizeof(int64_t))
+ return -1;
+
+ dp = av_malloc(count * sizeof(double));
if (!dp)
return AVERROR(ENOMEM);
for (i = 0; i < count; i++)
- dp[i] = tget_double(buf, s->le);
+ dp[i] = tget_double(&s->gb, s->le);
ap = doubles2str(dp, count, sep);
av_freep(&dp);
if (!ap)
@@ -261,17 +263,22 @@ static int add_doubles_metadata(const uint8_t **buf, int count,
return 0;
}
-static int add_shorts_metadata(const uint8_t **buf, int count, const char *name,
+static int add_shorts_metadata(int count, const char *name,
const char *sep, TiffContext *s)
{
char *ap;
int i;
- int *sp = av_malloc(count * sizeof(int));
+ int16_t *sp;
+
+ if (bytestream2_get_bytes_left(&s->gb) < count * sizeof(int16_t))
+ return -1;
+
+ sp = av_malloc(count * sizeof(int16_t));
if (!sp)
return AVERROR(ENOMEM);
for (i = 0; i < count; i++)
- sp[i] = tget_short(buf, s->le);
+ sp[i] = tget_short(&s->gb, s->le);
ap = shorts2str(sp, count, sep);
av_freep(&sp);
if (!ap)
@@ -280,12 +287,12 @@ static int add_shorts_metadata(const uint8_t **buf, int count, const char *name,
return 0;
}
-static int add_metadata(const uint8_t **buf, int count, int type,
+static int add_metadata(int count, int type,
const char *name, const char *sep, TiffContext *s)
{
switch(type) {
- case TIFF_DOUBLE: return add_doubles_metadata(buf, count, name, sep, s);
- case TIFF_SHORT : return add_shorts_metadata(buf, count, name, sep, s);
+ case TIFF_DOUBLE: return add_doubles_metadata(count, name, sep, s);
+ case TIFF_SHORT : return add_shorts_metadata(count, name, sep, s);
default : return AVERROR_INVALIDDATA;
};
}
@@ -575,22 +582,21 @@ static int init_image(TiffContext *s)
return 0;
}
-static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
- const uint8_t *buf, const uint8_t *end_buf)
+static int tiff_decode_tag(TiffContext *s)
{
unsigned tag, type, count, off, value = 0;
- int i, j;
+ int i, j, k, pos, start;
int ret;
uint32_t *pal;
- const uint8_t *rp, *gp, *bp;
double *dp;
- if (end_buf - buf < 12)
+ if (bytestream2_get_bytes_left(&s->gb) < 12)
return -1;
- tag = tget_short(&buf, s->le);
- type = tget_short(&buf, s->le);
- count = tget_long(&buf, s->le);
- off = tget_long(&buf, s->le);
+ tag = tget_short(&s->gb, s->le);
+ type = tget_short(&s->gb, s->le);
+ count = tget_long(&s->gb, s->le);
+ off = tget_long(&s->gb, s->le);
+ start = bytestream2_tell(&s->gb);
if (type == 0 || type >= FF_ARRAY_ELEMS(type_sizes)) {
av_log(s->avctx, AV_LOG_DEBUG, "Unknown tiff type (%u) encountered\n",
@@ -602,37 +608,29 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
switch (type) {
case TIFF_BYTE:
case TIFF_SHORT:
- buf -= 4;
- value = tget(&buf, type, s->le);
- buf = NULL;
+ bytestream2_seek(&s->gb, -4, SEEK_CUR);
+ value = tget(&s->gb, type, s->le);
break;
case TIFF_LONG:
value = off;
- buf = NULL;
break;
case TIFF_STRING:
if (count <= 4) {
- buf -= 4;
+ bytestream2_seek(&s->gb, -4, SEEK_CUR);
break;
}
default:
value = UINT_MAX;
- buf = start + off;
+ bytestream2_seek(&s->gb, off, SEEK_SET);
}
} else {
if (count <= 4 && type_sizes[type] * count <= 4) {
- buf -= 4;
+ bytestream2_seek(&s->gb, -4, SEEK_CUR);
} else {
- buf = start + off;
+ bytestream2_seek(&s->gb, off, SEEK_SET);
}
}
- if (buf && (buf < start || buf > end_buf)) {
- av_log(s->avctx, AV_LOG_ERROR,
- "Tag referencing position outside the image\n");
- return -1;
- }
-
switch (tag) {
case TIFF_WIDTH:
s->width = value;
@@ -659,8 +657,8 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
case TIFF_SHORT:
case TIFF_LONG:
s->bpp = 0;
- for (i = 0; i < count && buf < end_buf; i++)
- s->bpp += tget(&buf, type, s->le);
+ for (i = 0; i < count && bytestream2_get_bytes_left(&s->gb) > 0; i++)
+ s->bpp += tget(&s->gb, type, s->le);
break;
default:
s->bpp = -1;
@@ -721,15 +719,15 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
break;
case TIFF_STRIP_OFFS:
if (count == 1) {
- s->stripdata = NULL;
+ s->strippos = 0;
s->stripoff = value;
} else
- s->stripdata = start + off;
+ s->strippos = off;
s->strips = count;
if (s->strips == 1)
s->rps = s->height;
s->sot = type;
- if (s->stripdata > end_buf) {
+ if (s->strippos > bytestream2_size(&s->gb)) {
av_log(s->avctx, AV_LOG_ERROR,
"Tag referencing position outside the image\n");
return -1;
@@ -737,15 +735,15 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
break;
case TIFF_STRIP_SIZE:
if (count == 1) {
- s->stripsizes = NULL;
+ s->stripsizesoff = 0;
s->stripsize = value;
s->strips = 1;
} else {
- s->stripsizes = start + off;
+ s->stripsizesoff = off;
}
s->strips = count;
s->sstype = type;
- if (s->stripsizes > end_buf) {
+ if (s->stripsizesoff > bytestream2_size(&s->gb)) {
av_log(s->avctx, AV_LOG_ERROR,
"Tag referencing position outside the image\n");
return -1;
@@ -789,18 +787,16 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
case TIFF_PAL:
pal = (uint32_t *) s->palette;
off = type_sizes[type];
- if (count / 3 > 256 || end_buf - buf < count / 3 * off * 3)
+ if (count / 3 > 256 || bytestream2_get_bytes_left(&s->gb) < count / 3 * off * 3)
return -1;
- rp = buf;
- gp = buf + count / 3 * off;
- bp = buf + count / 3 * off * 2;
off = (type_sizes[type] - 1) << 3;
- for (i = 0; i < count / 3; i++) {
- j = 0xff << 24;
- j |= (tget(&rp, type, s->le) >> off) << 16;
- j |= (tget(&gp, type, s->le) >> off) << 8;
- j |= tget(&bp, type, s->le) >> off;
- pal[i] = j;
+ for (k = 2; k >= 0; k--) {
+ for (i = 0; i < count / 3; i++) {
+ if (k == 2)
+ pal[i] = 0xff << 24;
+ j = (tget(&s->gb, type, s->le) >> off) << (k * 8);
+ pal[i] |= j;
+ }
}
s->palette_is_set = 1;
break;
@@ -819,7 +815,7 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
s->fax_opts = value;
break;
#define ADD_METADATA(count, name, sep)\
- if (ret = add_metadata(&buf, count, type, name, sep, s) < 0) {\
+ if (ret = add_metadata(count, type, name, sep, s) < 0) {\
av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");\
return ret;\
}
@@ -835,7 +831,7 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
case TIFF_GEO_KEY_DIRECTORY:
ADD_METADATA(1, "GeoTIFF_Version", NULL);
ADD_METADATA(2, "GeoTIFF_Key_Revision", ".");
- s->geotag_count = tget_short(&buf, s->le);
+ s->geotag_count = tget_short(&s->gb, s->le);
if (s->geotag_count > count / 4 - 1) {
s->geotag_count = count / 4 - 1;
av_log(s->avctx, AV_LOG_WARNING, "GeoTIFF key directory buffer shorter than specified\n");
@@ -846,14 +842,14 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
return AVERROR(ENOMEM);
}
for (i = 0; i < s->geotag_count; i++) {
- s->geotags[i].key = tget_short(&buf, s->le);
- s->geotags[i].type = tget_short(&buf, s->le);
- s->geotags[i].count = tget_short(&buf, s->le);
+ s->geotags[i].key = tget_short(&s->gb, s->le);
+ s->geotags[i].type = tget_short(&s->gb, s->le);
+ s->geotags[i].count = tget_short(&s->gb, s->le);
if (!s->geotags[i].type)
- s->geotags[i].val = get_geokey_val(s->geotags[i].key, tget_short(&buf, s->le));
+ s->geotags[i].val = get_geokey_val(s->geotags[i].key, tget_short(&s->gb, s->le));
else
- s->geotags[i].offset = tget_short(&buf, s->le);
+ s->geotags[i].offset = tget_short(&s->gb, s->le);
}
break;
case TIFF_GEO_DOUBLE_PARAMS:
@@ -863,7 +859,7 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
return AVERROR(ENOMEM);
}
for (i = 0; i < count; i++)
- dp[i] = tget_double(&buf, s->le);
+ dp[i] = tget_double(&s->gb, s->le);
for (i = 0; i < s->geotag_count; i++) {
if (s->geotags[i].type == TIFF_GEO_DOUBLE_PARAMS) {
if (s->geotags[i].count == 0
@@ -883,6 +879,7 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
av_freep(&dp);
break;
case TIFF_GEO_ASCII_PARAMS:
+ pos = bytestream2_tell(&s->gb);
for (i = 0; i < s->geotag_count; i++) {
if (s->geotags[i].type == TIFF_GEO_ASCII_PARAMS) {
if (s->geotags[i].count == 0
@@ -894,7 +891,8 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");
return AVERROR(ENOMEM);
}
- memcpy(ap, &buf[s->geotags[i].offset], s->geotags[i].count);
+ bytestream2_seek(&s->gb, pos + s->geotags[i].offset, SEEK_SET);
+ bytestream2_get_buffer(&s->gb, ap, s->geotags[i].count);
ap[s->geotags[i].count - 1] = '\0'; //replace the "|" delimiter with a 0 byte
s->geotags[i].val = ap;
}
@@ -905,30 +903,31 @@ static int tiff_decode_tag(TiffContext *s, const uint8_t *start,
av_log(s->avctx, AV_LOG_DEBUG, "Unknown or unsupported tag %d/0X%0X\n",
tag, tag);
}
+ bytestream2_seek(&s->gb, start, SEEK_SET);
return 0;
}
static int decode_frame(AVCodecContext *avctx,
void *data, int *data_size, AVPacket *avpkt)
{
- const uint8_t *buf = avpkt->data;
- int buf_size = avpkt->size;
TiffContext *const s = avctx->priv_data;
AVFrame *picture = data;
AVFrame *const p = &s->picture;
- const uint8_t *orig_buf = buf, *end_buf = buf + buf_size;
unsigned off;
int id, le, ret;
int i, j, entries;
int stride;
unsigned soff, ssize;
uint8_t *dst;
+ GetByteContext stripsizes;
+ GetByteContext stripdata;
+
+ bytestream2_init(&s->gb, avpkt->data, avpkt->size);
//parse image header
- if (end_buf - buf < 8)
+ if (avpkt->size < 8)
return AVERROR_INVALIDDATA;
- id = AV_RL16(buf);
- buf += 2;
+ id = bytestream2_get_le16(&s->gb);
if (id == 0x4949)
le = 1;
else if (id == 0x4D4D)
@@ -947,25 +946,24 @@ static int decode_frame(AVCodecContext *avctx,
// As TIFF 6.0 specification puts it "An arbitrary but carefully chosen number
// that further identifies the file as a TIFF file"
- if (tget_short(&buf, le) != 42) {
+ if (tget_short(&s->gb, le) != 42) {
av_log(avctx, AV_LOG_ERROR,
"The answer to life, universe and everything is not correct!\n");
return -1;
}
- // Reset these pointers so we can tell if they were set this frame
- s->stripsizes = s->stripdata = NULL;
+ // Reset these offsets so we can tell if they were set this frame
+ s->stripsizesoff = s->strippos = 0;
/* parse image file directory */
- off = tget_long(&buf, le);
- if (off >= UINT_MAX - 14 || end_buf - orig_buf < off + 14) {
+ off = tget_long(&s->gb, le);
+ if (off >= UINT_MAX - 14 || avpkt->size < off + 14) {
av_log(avctx, AV_LOG_ERROR, "IFD offset is greater than image size\n");
return AVERROR_INVALIDDATA;
}
- buf = orig_buf + off;
- entries = tget_short(&buf, le);
+ bytestream2_seek(&s->gb, off, SEEK_SET);
+ entries = tget_short(&s->gb, le);
for (i = 0; i < entries; i++) {
- if (tiff_decode_tag(s, orig_buf, buf, end_buf) < 0)
+ if (tiff_decode_tag(s) < 0)
return -1;
- buf += 12;
}
for (i = 0; i<s->geotag_count; i++) {
@@ -985,7 +983,7 @@ static int decode_frame(AVCodecContext *avctx,
}
}
- if (!s->stripdata && !s->stripoff) {
+ if (!s->strippos && !s->stripoff) {
av_log(avctx, AV_LOG_ERROR, "Image data is missing\n");
return -1;
}
@@ -995,30 +993,38 @@ static int decode_frame(AVCodecContext *avctx,
if (s->strips == 1 && !s->stripsize) {
av_log(avctx, AV_LOG_WARNING, "Image data size missing\n");
- s->stripsize = buf_size - s->stripoff;
+ s->stripsize = avpkt->size - s->stripoff;
}
stride = p->linesize[0];
dst = p->data[0];
+
+ if (s->stripsizesoff) {
+ if (s->stripsizesoff >= avpkt->size)
+ return AVERROR_INVALIDDATA;
+ bytestream2_init(&stripsizes, avpkt->data + s->stripsizesoff, avpkt->size - s->stripsizesoff);
+ }
+ if (s->strippos) {
+ if (s->strippos >= avpkt->size)
+ return AVERROR_INVALIDDATA;
+ bytestream2_init(&stripdata, avpkt->data + s->strippos, avpkt->size - s->strippos);
+ }
+
for (i = 0; i < s->height; i += s->rps) {
- if (s->stripsizes) {
- if (s->stripsizes >= end_buf)
- return AVERROR_INVALIDDATA;
- ssize = tget(&s->stripsizes, s->sstype, s->le);
- } else
+ if (s->stripsizesoff)
+ ssize = tget(&stripsizes, s->sstype, s->le);
+ else
ssize = s->stripsize;
- if (s->stripdata) {
- if (s->stripdata >= end_buf)
- return AVERROR_INVALIDDATA;
- soff = tget(&s->stripdata, s->sot, s->le);
- } else
+ if (s->strippos)
+ soff = tget(&stripdata, s->sot, s->le);
+ else
soff = s->stripoff;
- if (soff > buf_size || ssize > buf_size - soff) {
+ if (soff > avpkt->size || ssize > avpkt->size - soff) {
av_log(avctx, AV_LOG_ERROR, "Invalid strip size/offset\n");
return -1;
}
- if (tiff_unpack_strip(s, dst, stride, orig_buf + soff, ssize,
+ if (tiff_unpack_strip(s, dst, stride, avpkt->data + soff, ssize,
FFMIN(s->rps, s->height - i)) < 0)
break;
dst += s->rps * stride;
@@ -1061,7 +1067,7 @@ static int decode_frame(AVCodecContext *avctx,
*picture = s->picture;
*data_size = sizeof(AVPicture);
- return buf_size;
+ return avpkt->size;
}
static av_cold int tiff_init(AVCodecContext *avctx)
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