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PhotoRec: Better signature for .pcx bitmap images

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This commit is contained in:
Christophe Grenier 2008-05-30 18:08:10 +02:00
parent 6c28be2d43
commit d0cdf68c5f
1 changed files with 52 additions and 16 deletions
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68
src/file_pcx.c
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@ -2,7 +2,7 @@
File: file_pcx.c
Copyright (C) 2006-2007 Christophe GRENIER <grenier@cgsecurity.org>
Copyright (C) 2006-2008 Christophe GRENIER <grenier@cgsecurity.org>
This software is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@ -29,7 +29,10 @@
#include <stdio.h>
#include "types.h"
#include "filegen.h"
#include "common.h"
#ifdef DEBUG_PCX
#include "log.h"
#endif
static void register_header_check_pcx(file_stat_t *file_stat);
static int header_check_pcx(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new);
@ -45,6 +48,35 @@ const file_hint_t file_hint_pcx= {
};
static const unsigned char pcx_header[1]= {0x0a};
struct pcx_file_entry {
uint8_t Manufacturer; /* should always be 0Ah */
uint8_t Version;
/* Version
* 0x00 PCX ver. 2.5 image data
* 0x02 PCX ver. 2.8 image data, with palette
* 0x03 PCX ver. 2.8 image data, without palette
* 0x04 PCX for Windows image data
* 0x05 PCX ver. 3.0 image data
*/
uint8_t Encoding; /* 0: uncompressed, 1: RLE compressed */
uint8_t BitsPerPixel;
uint16_t XMin; /* image width = XMax-XMin */
uint16_t YMin; /* image height = YMax-YMin */
uint16_t XMax;
uint16_t YMax;
uint16_t VertDPI;
uint8_t Palette[48];
uint8_t Reserved;
uint8_t ColorPlanes;
/* 4 -- 16 colors
* 3 -- 24 bit color (16.7 million colors)
*/
uint16_t BytesPerLine;
uint16_t PaletteType;
uint16_t HScrSize; /* only supported by */
uint16_t VScrSize; /* PC Paintbrush IV or higher */
uint8_t Filler[56];
} __attribute__ ((__packed__));
static void register_header_check_pcx(file_stat_t *file_stat)
{
@ -53,22 +85,26 @@ static void register_header_check_pcx(file_stat_t *file_stat)
static int header_check_pcx(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new)
{
/*
0x0a 0x00 PCX ver. 2.5 image data
0x0a 0x02 PCX ver. 2.8 image data, with palette
0x0a 0x03 PCX ver. 2.8 image data, without palette
0x0a 0x04 PCX for Windows image data
0x0a 0x05 PCX ver. 3.0 image data
buffer[2]==0 uncompressed
buffer[2]==1 RLE compressed
buffer[3] Number of bits of color used for each pixel
buffer[64] Reserved
*/
if(buffer[0]==0x0a && (buffer[1]<=5 && buffer[1]!=1) && buffer[2]<=1 &&
(buffer[3]==1 || buffer[3]==4 || buffer[3]==8 || buffer[3]==24) &&
buffer[64]==0)
const struct pcx_file_entry *pcx=(const struct pcx_file_entry *)buffer;
if(pcx->Manufacturer==0x0a &&
(pcx->Version<=5 && pcx->Version!=1) &&
pcx->Encoding <=1 &&
(pcx->BitsPerPixel==1 || pcx->BitsPerPixel==4 ||
pcx->BitsPerPixel==8 || pcx->BitsPerPixel==24) &&
pcx->Reserved==0 &&
le16(pcx->XMin) <= le16(pcx->XMax) &&
le16(pcx->YMin) <= le16(pcx->YMax) &&
pcx->BytesPerLine>0 &&
pcx->Filler[0]==0)
{
reset_file_recovery(file_recovery_new);
#ifdef DEBUG_PCX
log_info("X %u-%u, Y %u-%u\n",
le16(pcx->XMin), le16(pcx->XMax),
le16(pcx->YMin), le16(pcx->YMax));
log_info("ColorPlanes %u\n", pcx->ColorPlanes);
log_info("BytesPerLine %u - %u\n", pcx->BytesPerLine, (le16(pcx->XMax)-le16(pcx->XMin)+1)*pcx->BitsPerPixel/8);
#endif
file_recovery_new->extension=file_hint_pcx.extension;
return 1;
}