/*
File: dir_fat.c
Copyright (C) 1998-2007 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
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write the Free Software Foundation, Inc., 51
Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <ctype.h>
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#include "types.h"
#include "common.h"
#include "fat.h"
#include "lang.h"
#include "fnctdsk.h"
#include "testdisk.h"
#include "intrf.h"
#include "dir.h"
#include "fat_dir.h"
#include "log.h"
#define MSDOS_MKMODE(a,m) ((m & (a & ATTR_RO ? LINUX_S_IRUGO|LINUX_S_IXUGO : LINUX_S_IRWXUGO)) | (a & ATTR_DIR ? LINUX_S_IFDIR : LINUX_S_IFREG))
struct fat_dir_struct
{
struct fat_boot_sector*boot_sector;
};
static int date_dos2unix(const unsigned short f_time,const unsigned short f_date);
static file_data_t *fat1x_rootdir(disk_t *disk_car, const partition_t *partition, const int debug, const struct fat_boot_sector*fat_header);
static file_data_t *fat12_dir(disk_t *disk_car, const partition_t *partition, dir_data_t *dir_data, const unsigned long int first_cluster);
static file_data_t *fat16_dir(disk_t *disk_car, const partition_t *partition, dir_data_t *dir_data, const unsigned long int first_cluster);
static file_data_t *fat32_dir(disk_t *disk_car, const partition_t *partition, dir_data_t *dir_data, const unsigned long int first_cluster);
static inline void fat16_towchar(wchar_t *dst, const uint8_t *src, size_t len);
static void dir_partition_fat_close(dir_data_t *dir_data);
static int32_t secwest;
static inline void fat16_towchar(wchar_t *dst, const uint8_t *src, size_t len)
{
while (len--) {
*dst++ = src[0] | (src[1] << 8);
src += 2;
}
}
file_data_t *dir_fat_aux(const unsigned char*buffer, const unsigned int size, const unsigned int cluster_size)
{
const struct msdos_dir_entry *de=(const struct msdos_dir_entry*)buffer;
wchar_t unicode[1000];
unsigned char long_slots;
file_data_t *dir_list=NULL;
file_data_t *current_file=NULL;
GetNew:
long_slots = 0;
unicode[0]=0;
if (de->name[0] == (int8_t) DELETED_FLAG)
goto RecEnd;
if (de->attr == ATTR_EXT) {
unsigned int i;
const struct msdos_dir_slot *ds;
unsigned char id;
unsigned char slot;
unsigned char slots;
unsigned char sum;
unsigned char alias_checksum;
ParseLong:
slots = 0;
ds = (const struct msdos_dir_slot *) de;
id = ds->id;
if ((id & 0x40)==0)
goto RecEnd;
slots = id & ~0x40;
if (slots > 20 || slots==0) /* ceil(256 * 2 / 26) */
goto RecEnd;
long_slots = slots;
alias_checksum = ds->alias_checksum;
slot = slots;
while (1) {
int offset;
slot--;
offset = slot * 13;
fat16_towchar(unicode + offset, ds->name0_4, 5);
fat16_towchar(unicode + offset + 5, ds->name5_10, 6);
fat16_towchar(unicode + offset + 11, ds->name11_12, 2);
if ((ds->id & 0x40)!=0) {
unicode[offset + 13] = 0;
}
de++;
if((const void*)de>=(const void*)(buffer+size))
goto EODir;
if (slot == 0)
break;
ds = (const struct msdos_dir_slot *) de;
if (ds->attr != ATTR_EXT)
goto RecEnd; /* XXX */
if ((ds->id & ~0x40) != slot)
goto ParseLong;
if (ds->alias_checksum != alias_checksum)
goto ParseLong;
}
if (de->name[0] == (int8_t) DELETED_FLAG)
goto RecEnd;
if (de->attr == ATTR_EXT)
goto ParseLong;
if (IS_FREE(de->name) || ((de->attr & ATTR_VOLUME)!=0))
goto RecEnd;
for (sum = 0, i = 0; i < 8; i++)
sum = (((sum&1)<<7)|((sum&0xfe)>>1)) + de->name[i];
for (i = 0; i < 3; i++)
sum = (((sum&1)<<7)|((sum&0xfe)>>1)) + de->ext[i];
if (sum != alias_checksum)
long_slots = 0;
}
RecEnd:
if((unicode[0]==0) &&(de->attr != ATTR_EXT))
{ /* short name 8.3 */
int i;
int j=0;
for(i=0;(i<8)&&(de->name[i]!=' ');i++)
unicode[j++]=de->name[i];
if(de->ext[0]!=' ')
{
unicode[j++]='.';
for(i=0;(i<3)&&(de->ext[i]!=' ');i++)
unicode[j++]=de->ext[i];
}
unicode[j]=0;
}
if (((de->attr != ATTR_EXT)||(long_slots!=0)) && ((int8_t) unicode[0] != (int8_t) DELETED_FLAG) && !(de->attr & ATTR_VOLUME))
{
if(unicode[0]!=0)
{
unsigned int i;
file_data_t *new_file=MALLOC(sizeof(*new_file));
for(i=0;(unicode[i]!=0)&&(i<sizeof(new_file->name)-1);i++)
new_file->name[i]=(char) unicode[i];
new_file->name[i]=0;
new_file->filestat.st_dev=0;
new_file->filestat.st_ino=(le16(de->starthi)<<16)|le16(de->start);
new_file->filestat.st_mode = MSDOS_MKMODE(de->attr,(LINUX_S_IRWXUGO & ~(LINUX_S_IWGRP|LINUX_S_IWOTH)));
new_file->filestat.st_nlink=0;
new_file->filestat.st_uid=0;
new_file->filestat.st_gid=0;
new_file->filestat.st_rdev=0;
new_file->filestat.st_size=le32(de->size);
#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
new_file->filestat.st_blksize=cluster_size;
#ifdef HAVE_STRUCT_STAT_ST_BLOCKS
if(new_file->filestat.st_blksize!=0)
{
new_file->filestat.st_blocks=(new_file->filestat.st_size+new_file->filestat.st_blksize-1)/new_file->filestat.st_blksize;
}
#endif
#endif
new_file->filestat.st_atime=new_file->filestat.st_ctime=new_file->filestat.st_mtime=date_dos2unix(le16(de->time),le16(de->date));
new_file->prev=current_file;
new_file->next=NULL;
/* log_trace("fat: new file %s de=%p size=%u\n",new_file->name,de,de->size); */
if(current_file!=NULL)
current_file->next=new_file;
else
dir_list=new_file;
current_file=new_file;
}
else
{
return dir_list;
}
}
de++;
if((const void *)de<(const void *)(buffer+size-1))
goto GetNew;
EODir:
return dir_list;
}
static int day_n[] = { 0,31,59,90,120,151,181,212,243,273,304,334,0,0,0,0 };
/* JanFebMarApr May Jun Jul Aug Sep Oct Nov Dec */
/* Convert a MS-DOS time/date pair to a UNIX date (seconds since 1 1 70). */
static int date_dos2unix(const unsigned short f_time, const unsigned short f_date)
{
int month,year,secs;
/* first subtract and mask after that... Otherwise, if
f_date == 0, bad things happen */
month = ((f_date >> 5) - 1) & 15;
year = f_date >> 9;
secs = (f_time & 31)*2+60*((f_time >> 5) & 63)+(f_time >> 11)*3600+86400*
((f_date & 31)-1+day_n[month]+(year/4)+year*365-((year & 3) == 0 &&
month < 2 ? 1 : 0)+3653);
/* days since 1.1.70 plus 80's leap day */
return secs+secwest;
}
static file_data_t *fat12_dir(disk_t *disk_car, const partition_t *partition, dir_data_t *dir_data, const unsigned long int first_cluster)
{
const struct fat_dir_struct *ls=(const struct fat_dir_struct*)dir_data->private_dir_data;
const struct fat_boot_sector*fat_header=ls->boot_sector;
if(fat_header->cluster_size<1)
{
log_error("FAT12: Can't list files, bad cluster size\n");
return NULL;
}
if(fat_sector_size(fat_header)==0)
{
log_error("FAT12: Can't list files, bad sector size\n");
return NULL;
}
if(first_cluster==0)
return fat1x_rootdir(disk_car,partition,dir_data->debug,fat_header);
{
file_data_t *dir_list;
unsigned int cluster_size=fat_header->cluster_size;
unsigned char *buffer_dir=MALLOC(fat_sector_size(fat_header)*cluster_size*10);
unsigned int cluster;
unsigned int nbr_cluster;
int stop=0;
memset(buffer_dir,0,fat_sector_size(fat_header)*cluster_size*10);
for(cluster=first_cluster, nbr_cluster=0;
((cluster&0x0ff8)!=(unsigned)FAT12_EOC) && (cluster>=2) && (nbr_cluster<10) && (stop==0);
cluster=get_next_cluster(disk_car,partition, UP_FAT12,le16(fat_header->reserved), cluster), nbr_cluster++)
{
uint64_t start=partition->part_offset+(uint64_t)(le16(fat_header->reserved)+fat_header->fats*le16(fat_header->fat_length)+(get_dir_entries(fat_header)*32+fat_sector_size(fat_header)-1)/fat_sector_size(fat_header)+(cluster-2)*cluster_size)*fat_sector_size(fat_header);
if(dir_data->debug>0)
{
log_trace("FAT12: cluster=%u(0x%x), pos=%lu\n",cluster,cluster,(long unsigned)(start/fat_sector_size(fat_header)));
}
if(disk_car->read(disk_car, cluster_size*fat_sector_size(fat_header), buffer_dir+(uint64_t)fat_sector_size(fat_header)*cluster_size*nbr_cluster, start))
{
log_error("FAT12: Can't read directory cluster\n");
stop=1;
}
}
dir_list=dir_fat_aux(buffer_dir,fat_sector_size(fat_header)*cluster_size*nbr_cluster,cluster_size);
free(buffer_dir);
return dir_list;
}
}
static file_data_t *fat16_dir(disk_t *disk_car, const partition_t *partition, dir_data_t *dir_data, const unsigned long int first_cluster)
{
const struct fat_dir_struct *ls=(const struct fat_dir_struct*)dir_data->private_dir_data;
const struct fat_boot_sector*fat_header=ls->boot_sector;
if(fat_header->cluster_size<1)
{
log_error("FAT16: Can't list files, bad cluster size.\n");
return NULL;
}
if(fat_sector_size(fat_header)==0)
{
log_error("FAT16: Can't list files, bad sector size\n");
return NULL;
}
if(first_cluster==0)
return fat1x_rootdir(disk_car,partition,dir_data->debug,fat_header);
{
file_data_t *dir_list=NULL;
unsigned int cluster_size=fat_header->cluster_size;
unsigned char *buffer_dir=MALLOC(disk_car->sector_size*cluster_size*10);
unsigned int cluster;
unsigned int nbr_cluster;
int stop=0;
memset(buffer_dir,0,disk_car->sector_size*cluster_size*10);
/* Need to correct the test */
for(cluster=first_cluster, nbr_cluster=0;
((cluster&0xfff8)!=(unsigned)FAT16_EOC) && (cluster>=2) && (nbr_cluster<10)&&(stop==0);
cluster=get_next_cluster(disk_car,partition, UP_FAT16,le16(fat_header->reserved), cluster), nbr_cluster++)
{
uint64_t start=partition->part_offset+(uint64_t)(le16(fat_header->reserved)+fat_header->fats*le16(fat_header->fat_length)+(get_dir_entries(fat_header)*32+disk_car->sector_size-1)/disk_car->sector_size+(cluster-2)*cluster_size)*disk_car->sector_size;
if(dir_data->debug>0)
{
log_trace("FAT16 cluster=%u(0x%x), pos=%lu\n",cluster,cluster,(long unsigned)(start/disk_car->sector_size));
}
if(disk_car->read(disk_car, cluster_size*disk_car->sector_size, buffer_dir+(uint64_t)disk_car->sector_size*cluster_size*nbr_cluster, start))
{
log_error("FAT16: Can't read directory cluster\n");
stop=1;
}
}
dir_list=dir_fat_aux(buffer_dir,disk_car->sector_size*cluster_size*nbr_cluster,cluster_size);
free(buffer_dir);
return dir_list;
}
}
static file_data_t *fat32_dir(disk_t *disk_car, const partition_t *partition, dir_data_t *dir_data, const unsigned long int first_cluster)
{
const struct fat_dir_struct *ls=(const struct fat_dir_struct*)dir_data->private_dir_data;
const struct fat_boot_sector*fat_header=ls->boot_sector;
if(fat_header->cluster_size==0)
{
log_error("FAT32: Can't list files, bad cluster size.\n");
return NULL;
}
if(le32(fat_header->root_cluster)==0)
{
log_error("FAT32: Can't list files, bad root cluster.\n");
return NULL;
}
if(fat_sector_size(fat_header)==0)
{
log_error("FAT32: Can't list files, bad sector size.\n");
return NULL;
}
{
file_data_t *dir_list;
unsigned int cluster_size=fat_header->cluster_size;
unsigned char *buffer_dir=MALLOC(fat_sector_size(fat_header)*cluster_size*10);
unsigned int cluster;
unsigned int nbr_cluster;
int stop=0;
memset(buffer_dir,0,fat_sector_size(fat_header)*cluster_size*10);
/* Need to correct the test */
for(cluster=(first_cluster==0?le32(fat_header->root_cluster):first_cluster), nbr_cluster=0;
((cluster&0xffffff8)!=(unsigned)FAT32_EOC) && (cluster>=2) && (nbr_cluster<10) && (stop==0);
cluster=get_next_cluster(disk_car,partition, UP_FAT32,le16(fat_header->reserved), cluster), nbr_cluster++)
{
uint64_t start=partition->part_offset+(uint64_t)(le16(fat_header->reserved)+fat_header->fats*le32(fat_header->fat32_length)+(cluster-2)*cluster_size)*fat_sector_size(fat_header);
if(dir_data->debug>0)
{
log_trace("FAT32 cluster=%u(0x%x), pos=%lu\n",cluster,cluster,(long unsigned)(start/fat_sector_size(fat_header)));
}
if(disk_car->read(disk_car, cluster_size*fat_sector_size(fat_header), buffer_dir+(uint64_t)fat_sector_size(fat_header)*cluster_size*nbr_cluster, start))
{
log_error("FAT32: Can't read directory cluster\n");
stop=1;
}
// log_trace("read cluster %u\n",cluster);
}
// log_trace("nbr_cluster=%u\n",nbr_cluster);
dir_list=dir_fat_aux(buffer_dir,fat_sector_size(fat_header)*cluster_size*nbr_cluster,cluster_size);
free(buffer_dir);
return dir_list;
}
}
static file_data_t *fat1x_rootdir(disk_t *disk_car, const partition_t *partition, const int debug, const struct fat_boot_sector*fat_header)
{
unsigned int root_size=(get_dir_entries(fat_header)*32+disk_car->sector_size-1)/disk_car->sector_size*disk_car->sector_size;
if(debug>1)
{
log_trace("fat1x_rootdir root_size=%u sectors\n",root_size/disk_car->sector_size);
}
{
file_data_t *res=NULL;
uint64_t start;
unsigned char *buffer_dir;
buffer_dir=(unsigned char*)MALLOC(root_size);
start=partition->part_offset+(uint64_t)((le16(fat_header->reserved)+fat_header->fats*le16(fat_header->fat_length))*disk_car->sector_size);
if(disk_car->read(disk_car, root_size, buffer_dir, start))
{
log_error("FAT 1x: Can't read root directory\n");
free(buffer_dir);
return NULL;
}
res=dir_fat_aux(buffer_dir,root_size,fat_header->cluster_size);
free(buffer_dir);
return res;
}
}
static void set_secwest(void)
{
struct tm *tmptr;
time_t t;
t = time(NULL);
tmptr = localtime(&t);
#ifdef HAVE_STRUCT_TM_TM_GMTOFF
secwest = -1 * tmptr->tm_gmtoff;
#elif defined (DJGPP)
secwest = 0;
#else
#if defined (__CYGWIN__)
secwest = _timezone;
#else
secwest = timezone;
#endif
/* account for daylight savings */
if (tmptr->tm_isdst)
secwest -= 3600;
#endif
}
int dir_partition_fat_init(disk_t *disk_car, const partition_t *partition, dir_data_t *dir_data, const int debug)
{
static unsigned char *buffer;
static struct fat_dir_struct *ls;
buffer=(unsigned char*)MALLOC(0x200);
if(disk_car->read(disk_car,0x200, buffer, partition->part_offset+(uint64_t)partition->boot_sector*disk_car->sector_size))
{
free(buffer);
return -1;
}
set_secwest();
ls=(struct fat_dir_struct *)MALLOC(sizeof(*ls));
ls->boot_sector=(struct fat_boot_sector*)buffer;
strncpy(dir_data->current_directory,"/",sizeof(dir_data->current_directory));
dir_data->current_inode=0;
dir_data->debug=debug;
dir_data->copy_file=NULL;
dir_data->close=dir_partition_fat_close;
dir_data->local_dir=NULL;
dir_data->private_dir_data=ls;
switch(partition->upart_type)
{
case UP_FAT12:
dir_data->get_dir=fat12_dir;
break;
case UP_FAT16:
dir_data->get_dir=fat16_dir;
break;
case UP_FAT32:
dir_data->get_dir=fat32_dir;
break;
default:
log_critical("Not a valid FAT type (upart_type=%u)\n",partition->upart_type);
free(ls->boot_sector);
free(ls);
dir_data->private_dir_data=NULL;
return -1;
}
return 0;
}
static void dir_partition_fat_close(dir_data_t *dir_data)
{
struct fat_dir_struct *ls=(struct fat_dir_struct*)dir_data->private_dir_data;
free(ls->boot_sector);
free(ls);
}
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