-const char deanimate_rcs[] = "$Id: deanimate.c,v 1.3 2001/07/15 13:57:50 jongfoster Exp $";
+const char deanimate_rcs[] = "$Id: deanimate.c,v 1.18 2008/03/28 15:13:38 fabiankeil Exp $";
/*********************************************************************
*
* File : $Source: /cvsroot/ijbswa/current/deanimate.c,v $
*
- * Purpose : Declares functions to deanimate GIF images on the fly.
+ * Purpose : Declares functions to manipulate binary images on the
+ * fly. High-level functions include:
+ * - Deanimation of GIF images
*
* Functions declared include: gif_deanimate, buf_free,
- * buf_copy, buf_getbyte, gif_skip_data_block, and
- * gif_extract_image
+ * buf_copy, buf_getbyte, gif_skip_data_block
+ * and gif_extract_image
*
- * Copyright : Written by and Copyright (C) 2001 by the the SourceForge
- * IJBSWA team. http://ijbswa.sourceforge.net
+ * Copyright : Written by and Copyright (C) 2001 - 2004, 2006 by the
+ * SourceForge Privoxy team. http://www.privoxy.org/
*
* Based on the GIF file format specification (see
* http://tronche.com/computer-graphics/gif/gif89a.html)
*
* Revisions :
* $Log: deanimate.c,v $
+ * Revision 1.18 2008/03/28 15:13:38 fabiankeil
+ * Remove inspect-jpegs action.
+ *
+ * Revision 1.17 2007/08/05 13:42:22 fabiankeil
+ * #1763173 from Stefan Huehner: declare some more functions static.
+ *
+ * Revision 1.16 2007/07/14 08:01:58 fabiankeil
+ * s@failiure@failure@
+ *
+ * Revision 1.15 2007/01/03 14:39:19 fabiankeil
+ * Fix a gcc43 warning and mark the binbuffer
+ * as immutable for buf_getbyte().
+ *
+ * Revision 1.14 2006/07/18 14:48:45 david__schmidt
+ * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
+ * with what was really the latest development (the v_3_0_branch branch)
+ *
+ * Revision 1.12.2.1 2004/10/03 12:53:32 david__schmidt
+ * Add the ability to check jpeg images for invalid
+ * lengths of comment blocks. Defensive strategy
+ * against the exploit:
+ * Microsoft Security Bulletin MS04-028
+ * Buffer Overrun in JPEG Processing (GDI+) Could
+ * Allow Code Execution (833987)
+ * Enabled with +inspect-jpegs in actions files.
+ *
+ * Revision 1.12 2002/05/12 21:36:29 jongfoster
+ * Correcting function comments
+ *
+ * Revision 1.11 2002/03/26 22:29:54 swa
+ * we have a new homepage!
+ *
+ * Revision 1.10 2002/03/24 13:25:43 swa
+ * name change related issues
+ *
+ * Revision 1.9 2002/03/13 00:27:04 jongfoster
+ * Killing warnings
+ *
+ * Revision 1.8 2002/03/09 19:42:47 jongfoster
+ * Fixing more warnings
+ *
+ * Revision 1.7 2002/03/08 17:46:04 jongfoster
+ * Fixing int/size_t warnings
+ *
+ * Revision 1.6 2002/03/07 03:46:17 oes
+ * Fixed compiler warnings
+ *
+ * Revision 1.5 2001/09/10 10:16:06 oes
+ * Silenced compiler warnings
+ *
+ * Revision 1.4 2001/07/18 12:28:49 oes
+ * - Added feature for extracting the first frame
+ * to gif_deanimate
+ * - Separated image buffer extension into buf_extend
+ * - Extended gif deanimation to GIF87a (untested!)
+ * - Cosmetics
+ *
* Revision 1.3 2001/07/15 13:57:50 jongfoster
* Adding #includes string.h and miscutil.h
*
#include <string.h>
#include <fcntl.h>
+#include "errlog.h"
#include "project.h"
#include "deanimate.h"
#include "miscutil.h"
*
* Description : Ensure that a given binbuffer can hold a given amount
* of bytes, by reallocating its buffer if necessary.
- * Allocate new mem in chunks of 1000 bytes, so we don't
+ * Allocate new mem in chunks of 1024 bytes, so we don't
* have to realloc() too often.
*
* Parameters :
* 2 : length = Desired minimum size
*
*
- * Returns : 0 on success, 1 on failiure.
+ * Returns : 0 on success, 1 on failure.
*
*********************************************************************/
-int buf_extend(struct binbuffer *buf, int length)
+static int buf_extend(struct binbuffer *buf, size_t length)
{
char *newbuf;
if (buf->offset + length > buf->size)
{
- buf->size = buf->size + length + 1000 - (buf->size + length) % 1000;
+ buf->size = ((buf->size + length + (size_t)1023) & ~(size_t)1023);
newbuf = (char *)realloc(buf->buffer, buf->size);
if (newbuf == NULL)
* 2 : dst = Pointer to the destination binbuffer
* 3 : length = Number of bytes to be copied
*
- * Returns : 0 on success, 1 on failiure.
+ * Returns : 0 on success, 1 on failure.
*
*********************************************************************/
-int buf_copy(struct binbuffer *src, struct binbuffer *dst, int length)
+static int buf_copy(struct binbuffer *src, struct binbuffer *dst, size_t length)
{
/*
* given offset
*
* Parameters :
- * 1 : buf = Pointer to the source binbuffer
+ * 1 : src = Pointer to the source binbuffer
* 2 : offset = Offset to the desired byte
*
- * Returns : The byte on success, or 0 on failiure
+ * Returns : The byte on success, or 0 on failure
*
*********************************************************************/
-unsigned char buf_getbyte(struct binbuffer *src, int offset)
+static unsigned char buf_getbyte(const struct binbuffer *src, size_t offset)
{
if (src->offset + offset < src->size)
{
* Parameters :
* 1 : buf = Pointer to the binbuffer
*
- * Returns : 0 on success, or 1 on failiure
+ * Returns : 0 on success, or 1 on failure
*
*********************************************************************/
-int gif_skip_data_block(struct binbuffer *buf)
+static int gif_skip_data_block(struct binbuffer *buf)
{
unsigned char c;
* by a one-byte length field, with the last chunk having
* zero length.
*/
- while(c = buf_getbyte(buf, 0))
+ while((c = buf_getbyte(buf, 0)) != '\0')
{
- if ((buf->offset += c + 1) >= buf->size - 1)
+ buf->offset += (size_t)c + 1;
+ if (buf->offset >= buf->size - 1)
{
return 1;
}
* 1 : src = Pointer to the source binbuffer
* 2 : dst = Pointer to the destination binbuffer
*
- * Returns : 0 on success, or 1 on failiure
+ * Returns : 0 on success, or 1 on failure
*
*********************************************************************/
-int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
+static int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
{
unsigned char c;
-
+
/*
* Remember the colormap flag and copy the image head
*/
*/
if (c & 0x80)
{
- if (buf_copy(src, dst, 3 * (1 << ((c & 0x07) + 1))))
+ int map_length = 3 * (1 << ((c & 0x07) + 1));
+ if (map_length <= 0)
+ {
+ log_error(LOG_LEVEL_DEANIMATE,
+ "colormap length = %d (%c)?", map_length, c);
+ return 1;
+ }
+ if (buf_copy(src, dst, (size_t)map_length))
{
return 1;
}
/*
* Copy the image chunk by chunk.
*/
- while(c = buf_getbyte(src, 0))
+ while((c = buf_getbyte(src, 0)) != '\0')
{
- if (buf_copy(src, dst, c + 1)) return 1;
+ if (buf_copy(src, dst, 1 + (size_t) c)) return 1;
}
if (buf_copy(src, dst, 1)) return 1;
* 3 : get_first_image = Flag: If set, get the first image
* If unset (default), get the last
*
- * Returns : 0 on success, or 1 on failiure
+ * Returns : 0 on success, or 1 on failure
*
*********************************************************************/
int gif_deanimate(struct binbuffer *src, struct binbuffer *dst, int get_first_image)
*/
if(c & 0x80)
{
- if (buf_copy(src, dst, 3 * (1 << ((c & 0x07) + 1))))
+ int map_length = 3 * (1 << ((c & 0x07) + 1));
+ if (map_length <= 0)
+ {
+ log_error(LOG_LEVEL_DEANIMATE,
+ "colormap length = %d (%c)?", map_length, c);
+ return 1;
+ }
+ if (buf_copy(src, dst, (size_t)map_length))
{
return 1;
}