testdisk/src/file_exe.c

1011 lines
33 KiB
C

/*
File: file_exe.c
Copyright (C) 1998-2005,2007 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.
*/
#if !defined(SINGLE_FORMAT) || defined(SINGLE_FORMAT_exe)
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <stdio.h>
#include "types.h"
#include "common.h"
#include "filegen.h"
#include "pe.h"
#include "log.h"
#if defined(__FRAMAC__)
#include "__fc_builtin.h"
#endif
/*@ requires \valid(file_stat); */
static void register_header_check_exe(file_stat_t *file_stat);
const file_hint_t file_hint_exe= {
.extension="exe",
.description="MS Windows executable",
.max_filesize=PHOTOREC_MAX_FILE_SIZE,
.recover=1,
.enable_by_default=1,
.register_header_check=&register_header_check_exe
};
static const char *extension_dll="dll";
static const unsigned char exe_header[2] = {'M','Z'};
struct rsrc_entries_s
{
uint32_t Type;
uint32_t Pos;
} __attribute__ ((gcc_struct, __packed__));
struct rsrc_offlen
{
uint32_t off;
uint32_t len;
} __attribute__ ((gcc_struct, __packed__));
struct PE_index
{
uint16_t len;
uint16_t val_len;
uint16_t type; /* 0=binary data, 1=text*/
} __attribute__ ((gcc_struct, __packed__));
static char vs_version_info[32]={
'V', 0x0, 'S', 0x0, '_', 0x0, 'V', 0x0, 'E', 0x0, 'R', 0x0, 'S', 0x0, 'I', 0x0,
'O', 0x0, 'N', 0x0, '_', 0x0, 'I', 0x0, 'N', 0x0, 'F', 0x0, 'O', 0x0, 0x0, 0x0
};
static char StringFileInfo[30]={
'S', 0x0, 't', 0x0, 'r', 0x0, 'i', 0x0, 'n', 0x0, 'g', 0x0, 'F', 0x0, 'i', 0x0,
'l', 0x0, 'e', 0x0, 'I', 0x0, 'n', 0x0, 'f', 0x0, 'o', 0x0, 0x0, 0x0
};
static char OriginalFilename[34]={
'O', 0x0, 'r', 0x0, 'i', 0x0, 'g', 0x0, 'i', 0x0, 'n', 0x0, 'a', 0x0, 'l', 0x0,
'F', 0x0, 'i', 0x0, 'l', 0x0, 'e', 0x0, 'n', 0x0, 'a', 0x0, 'm', 0x0, 'e', 0x0,
0x0, 0x0
};
static char InternalName[24]={
'I', 0x0, 'n', 0x0, 't', 0x0, 'e', 0x0, 'r', 0x0, 'n', 0x0, 'a', 0x0, 'l', 0x0,
'N', 0x0, 'a', 0x0, 'm', 0x0, 'e', 0x0
};
/*@
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@ requires needle_len > 0;
@ requires \valid_read(buffer+(0..end-1));
@ requires \valid_read(needle+(0..needle_len-1));
@ requires \separated(file_recovery, buffer+(..), needle+(..));
@*/
static int parse_String(file_recovery_t *file_recovery, const char*buffer, const unsigned int end, const char *needle, const unsigned int needle_len, const int force_ext)
{
const struct PE_index *PE_index;
unsigned int len;
unsigned int val_len;
unsigned int type;
if(6 > end)
{
return -1;
}
PE_index=(const struct PE_index*)buffer;
len=le16(PE_index->len);
val_len=le16(PE_index->val_len);
type=le16(PE_index->type);
#ifdef DEBUG_EXE
log_info("parse_String len=%u val_len=%u type=%u\n", len, val_len, type);
#endif
if(len > end)
return -1;
if(6 + 2 * val_len > len)
return -1;
#ifdef DEBUG_EXE
dump_log(buffer, len);
#endif
// type=1 => text
if(6+needle_len < end && type==1 && memcmp(&buffer[6], needle, needle_len)==0)
{
if(6 + needle_len + 2 * val_len > len)
return -1;
file_rename_unicode(file_recovery, buffer, end, 6+needle_len, NULL, force_ext);
}
return len;
}
/*@
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@ requires needle_len > 0;
@ requires \valid_read(buffer+(0..end-1));
@ requires \valid_read(needle+(0..needle_len-1));
@ requires \separated(file_recovery, buffer+(..), needle+(..));
@*/
static int parse_StringArray(file_recovery_t *file_recovery, const char*buffer, const unsigned int end, const char *needle, const unsigned int needle_len, const int force_ext)
{
unsigned int pos=0;
#ifdef DEBUG_EXE
log_info("parse_StringArray end=%u\n", end);
#endif
/*@
@ loop variant end - pos;
@*/
while(pos<end)
{
const int res=parse_String(file_recovery, &buffer[pos], end - pos, needle, needle_len, force_ext);
if(res <= 0)
return -1;
/*@ assert res > 0; */
pos+=res;
/* Padding */
if((pos & 0x03)!=0)
pos+=2;
}
return 0;
}
/*@
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@ requires needle_len > 0;
@ requires \valid_read(buffer+(0..end-1));
@ requires \valid_read(needle+(0..needle_len-1));
@ requires \separated(file_recovery, buffer+(..), needle+(..));
@*/
static int parse_StringTable(file_recovery_t *file_recovery, const char*buffer, const unsigned int end, const char *needle, const unsigned int needle_len, const int force_ext)
{
const struct PE_index *PE_index;
unsigned int pos;
unsigned int len;
unsigned int val_len;
if(6 > end)
{
return -1;
}
PE_index=(const struct PE_index*)buffer;
/*@ assert \valid_read(PE_index); */
len=le16(PE_index->len);
val_len=le16(PE_index->val_len);
#ifdef DEBUG_EXE
log_info("parse_StringTable len=%u val_len=%u type=%u\n", len, val_len, le16(PE_index->type));
#endif
if(len > end)
return -1;
/* szKey: language identifier + code page */
pos = 6 + 2*8 + 2;
/* Padding */
if((pos & 0x03)!=0)
pos+=2;
if(pos > len)
return -1;
/* An array of one or more String structures */
return parse_StringArray(file_recovery, &buffer[pos], len - pos, needle, needle_len, force_ext);
}
/*@
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@ requires needle_len > 0;
@ requires \valid_read(buffer+(0..end-1));
@ requires \valid_read(needle+(0..needle_len-1));
@ requires \separated(file_recovery, buffer+(..), needle+(..));
@*/
static int parse_StringFileInfo(file_recovery_t *file_recovery, const char*buffer, const unsigned int end, const char *needle, const unsigned int needle_len, const int force_ext)
{
/* https://docs.microsoft.com/en-us/windows/win32/menurc/stringfileinfo */
const struct PE_index *PE_index;
unsigned int pos;
unsigned int len;
unsigned int val_len;
if(6 > end)
{
return -1;
}
PE_index=(const struct PE_index*)buffer;
/*@ assert \valid_read(PE_index); */
len=le16(PE_index->len);
val_len=le16(PE_index->val_len);
#ifdef DEBUG_EXE
log_info("parse_StringFileInfo len=%u val_len=%u type=%u\n", len, val_len, le16(PE_index->type));
#endif
if(len > end)
return -1;
if(6 + sizeof(StringFileInfo) > end)
return 0;
/* szKey == StringFileInfo ? */
if(memcmp(&buffer[6], StringFileInfo, sizeof(StringFileInfo))!=0)
return 0;
if(val_len!=0)
return -1;
pos=6 + sizeof(StringFileInfo);
/* Padding */
if((pos & 0x03)!=0)
pos+=2;
if(pos > len)
return -1;
return parse_StringTable(file_recovery, &buffer[pos], len - pos, needle, needle_len, force_ext);
}
/*@
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@ requires end > 0;
@ requires needle_len > 0;
@ requires \valid_read(buffer+(0..end-1));
@ requires \valid_read(needle+(0..needle_len-1));
@ requires \separated(vs_version_info+(..), file_recovery, buffer+(..), needle+(..));
@ behavior types: requires \separated(vs_version_info+(..), \union(file_recovery, buffer+(..), needle+(..)));
@*/
static int parse_VS_VERSIONINFO(file_recovery_t *file_recovery, const char*buffer, const unsigned int end, const char *needle, const unsigned int needle_len, const int force_ext)
{
/* https://docs.microsoft.com/en-us/windows/win32/menurc/vs-versioninfo */
unsigned int pos=0;
const struct PE_index *PE_index;
const char *stringName;
unsigned int len;
unsigned int val_len;
if(6 > end)
{
return -1;
}
PE_index=(const struct PE_index*)buffer;
/*@ assert \valid_read(PE_index); */
len=le16(PE_index->len);
val_len=le16(PE_index->val_len);
#ifdef DEBUG_EXE
log_info("parse_VS_VERSIONINFO len=%u val_len=%u type=%u\n", len, val_len, le16(PE_index->type));
#endif
if(len==0 && val_len==0)
{
return -1;
}
if(val_len > len)
return -1;
if(len > end)
return -1;
/*@ assert len <= end; */
pos+=6;
if(pos + sizeof(vs_version_info) >= len)
return -1;
stringName=&buffer[pos];
/* szKey */
if(memcmp(stringName, vs_version_info, sizeof(vs_version_info))!=0)
return -1;
pos+=sizeof(vs_version_info);
/* Padding1 */
if((pos & 0x03)!=0)
pos+=2;
/* VS_FIXEDFILEINFO */
pos+=val_len;
/* Padding2 */
if((pos & 0x03)!=0)
pos+=2;
if(pos > len)
return -1;
/* Children */
/* An array of zero or one StringFileInfo structures, and zero or one
* VarFileInfo structures that are children of the current VS_VERSIONINFO structure. */
if(parse_StringFileInfo(file_recovery, &buffer[pos], len - pos, needle, needle_len, force_ext) < 0)
return -1;
return 0;
}
/*@
@ requires \valid(file);
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@*/
static void PEVersion(FILE *file, const unsigned int offset, const unsigned int length, file_recovery_t *file_recovery)
{
char buffer[1024*1024];
#ifdef DEBUG_EXE
log_info("PEVersion(file, %u, %u, file_recovery)\n", offset, length);
#endif
if(length==0 || length > 1024*1024)
return;
if(fseek(file, offset, SEEK_SET)<0)
return ;
if(fread(&buffer, length, 1, file) != 1)
{
return ;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)&buffer, sizeof(buffer));
#endif
if(parse_VS_VERSIONINFO(file_recovery, (const char *)&buffer, length, OriginalFilename, sizeof(OriginalFilename), 0)==0)
{
return;
}
parse_VS_VERSIONINFO(file_recovery, buffer, length, InternalName, sizeof(InternalName), 1);
}
/*@
@ requires \valid(file);
@ requires base <= 0x7fffffff;
@ requires \valid_read(pe_sections);
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@ requires \valid_read(rsrc_entry);
@*/
static int pe_resource_language_aux(FILE *file, const unsigned int base, const struct pe_image_section_hdr *pe_sections, const unsigned int nbr_sections, file_recovery_t *file_recovery, const struct rsrc_entries_s *rsrc_entry)
{
struct rsrc_offlen buffer;
uint32_t off;
unsigned int len;
unsigned int j;
#ifdef DEBUG_EXE
log_info("resource lang=%u, %x, offset %u\n",
le32(rsrc_entry->Type),
le32(rsrc_entry->Pos),
base + (le32(rsrc_entry->Pos) & 0x7fffffff));
#endif
if(fseek(file, base + (le32(rsrc_entry->Pos) & 0x7fffffff), SEEK_SET)<0)
{
return -1;
}
if(fread(&buffer, 1, sizeof(buffer), file) != sizeof(buffer))
{
return -1;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)&buffer, sizeof(buffer));
#endif
off=le32(buffer.off);
len=le32(buffer.len);
/*TODO: loop invariant 0 <= j <= nbr_sections; */
for(j=0; j<nbr_sections; j++)
{
const struct pe_image_section_hdr *pe_section=&pe_sections[j];
const uint32_t virt_addr_start=le32(pe_section->VirtualAddress);
const uint64_t virt_addr_end=(uint64_t)virt_addr_start + le32(pe_section->SizeOfRawData);
if(virt_addr_end <= 0xffffffff && virt_addr_start <= off && off < virt_addr_end && (uint64_t)off - virt_addr_start + base <=0xffffffff)
{
PEVersion(file, off - virt_addr_start + base, len, file_recovery);
return 0;
}
}
return 1;
}
/*@
@ requires \valid(file);
@ requires base <= 0x7fffffff;
@ requires dir_start <= 0x7fffffff;
@ requires \valid_read(pe_sections);
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@*/
static void pe_resource_language(FILE *file, const unsigned int base, const unsigned int dir_start, const struct pe_image_section_hdr *pe_sections, const unsigned int nbr_sections, file_recovery_t *file_recovery)
{
struct rsrc_entries_s *rsrc_entries;
unsigned int count;
unsigned int i;
#ifdef DEBUG_EXE
log_info("pe_resource_language(file, %u, %u)\n", base, dir_start);
#endif
{
unsigned char buffer[16];
unsigned int nameEntries;
unsigned int idEntries;
if(fseek(file, base + dir_start, SEEK_SET)<0)
return ;
if(fread(buffer, 1, sizeof(buffer), file) != sizeof(buffer))
return ;
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)buffer, sizeof(buffer));
#endif
nameEntries = buffer[12]+(buffer[13]<<8);
idEntries = buffer[14]+(buffer[15]<<8);
count = nameEntries + idEntries;
}
#ifdef DEBUG_EXE
log_info("pe_resource_language count=%u\n", count);
#endif
if(count==0 || count > 1024)
return ;
/*@ assert 0 < count <= 1024; */
#ifdef __FRAMAC__
rsrc_entries=(struct rsrc_entries_s *)MALLOC(1024 * sizeof(struct rsrc_entries_s));
#else
rsrc_entries=(struct rsrc_entries_s *)MALLOC(count * sizeof(struct rsrc_entries_s));
#endif
/*@ assert \valid((char *)rsrc_entries + (0 .. (unsigned long)((unsigned long)count * sizeof(struct rsrc_entries_s)) - 1)); */
if(fread(rsrc_entries, sizeof(struct rsrc_entries_s), count, file) != count)
{
free(rsrc_entries);
return ;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)rsrc_entries, count * sizeof(struct rsrc_entries_s));
#endif
for(i=0; i<count; i++)
{
const struct rsrc_entries_s *rsrc_entry=&rsrc_entries[i];
int res=pe_resource_language_aux(file, base, pe_sections, nbr_sections, file_recovery, rsrc_entry);
if(res <= 0)
{
free(rsrc_entries);
return ;
}
}
free(rsrc_entries);
}
/*@
@ requires \valid(file);
@ requires base <= 0x7fffffff;
@ requires dir_start <= 0x7fffffff;
@ requires \valid_read(pe_sections);
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@*/
static void pe_resource_id(FILE *file, const unsigned int base, const unsigned int dir_start, const struct pe_image_section_hdr *pe_sections, const unsigned int nbr_sections, file_recovery_t *file_recovery)
{
struct rsrc_entries_s *rsrc_entries;
unsigned int count;
unsigned int i;
#ifdef DEBUG_EXE
log_info("pe_resource_id(file, %u, %u)\n", base, dir_start);
#endif
{
unsigned char buffer[16];
unsigned int nameEntries;
unsigned int idEntries;
if(fseek(file, base + dir_start, SEEK_SET)<0)
return ;
if(fread(buffer, 1, sizeof(buffer), file) != sizeof(buffer))
return ;
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)buffer, sizeof(buffer));
#endif
nameEntries = buffer[12]+(buffer[13]<<8);
idEntries = buffer[14]+(buffer[15]<<8);
count = nameEntries + idEntries;
}
if(count==0 || count > 1024)
return ;
/*@ assert 0 < count <= 1024; */
#ifdef __FRAMAC__
rsrc_entries=(struct rsrc_entries_s *)MALLOC(1024 * sizeof(struct rsrc_entries_s));
#else
rsrc_entries=(struct rsrc_entries_s *)MALLOC(count * sizeof(struct rsrc_entries_s));
#endif
/*@ assert \valid((char *)rsrc_entries + (0 .. (unsigned long)((unsigned long)count * sizeof(struct rsrc_entries_s)) - 1)); */
if(fread(rsrc_entries, sizeof(struct rsrc_entries_s), count, file) != count)
{
free(rsrc_entries);
return ;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)rsrc_entries, count * sizeof(struct rsrc_entries_s));
#endif
for(i=0; i<count; i++)
{
const struct rsrc_entries_s *rsrc_entry=&rsrc_entries[i];
#ifdef DEBUG_EXE
log_info("resource id=%u, %x, offset %u\n",
le32(rsrc_entry->Type),
le32(rsrc_entry->Pos),
base + (le32(rsrc_entry->Pos) & 0x7fffffff));
#endif
if((le32(rsrc_entry->Pos) & 0x80000000)!=0)
{
pe_resource_language(file,
base,
le32(rsrc_entry->Pos) & 0x7fffffff,
pe_sections, nbr_sections, file_recovery);
}
}
free(rsrc_entries);
}
/*@
@ requires \valid(file);
@ requires \valid_read(pe_sections);
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@*/
static void pe_resource_type(FILE *file, const unsigned int base, const unsigned int dir_start, const struct pe_image_section_hdr *pe_sections, const unsigned int nbr_sections, file_recovery_t *file_recovery)
{
struct rsrc_entries_s *rsrc_entries;
unsigned int count;
unsigned int i;
#ifdef DEBUG_EXE
log_info("pe_resource_type(file, %u, %u)\n", base, dir_start);
#endif
/* TODO: remove these artifical limits ? */
if(base > 0x7fffffff || dir_start > 0x7fffffff)
return ;
/*@ assert base <= 0x7fffffff; */
{
unsigned char buffer[16];
unsigned int nameEntries;
unsigned int idEntries;
if(fseek(file, base, SEEK_SET)<0)
return ;
if(fread(buffer, 1, sizeof(buffer), file) != sizeof(buffer))
return ;
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)buffer, sizeof(buffer));
#endif
nameEntries = buffer[12]+(buffer[13]<<8);
idEntries = buffer[14]+(buffer[15]<<8);
count = nameEntries + idEntries;
}
if(count==0 || count > 1024)
return ;
/*@ assert 0 < count <= 1024; */
#ifdef __FRAMAC__
rsrc_entries=(struct rsrc_entries_s *)MALLOC(1024 * sizeof(struct rsrc_entries_s));
#else
rsrc_entries=(struct rsrc_entries_s *)MALLOC(count * sizeof(struct rsrc_entries_s));
#endif
/*@ assert \valid((char *)rsrc_entries + (0 .. (unsigned long)((unsigned long)count * sizeof(struct rsrc_entries_s)) - 1)); */
if(fread(rsrc_entries, sizeof(struct rsrc_entries_s), count, file) != count)
{
free(rsrc_entries);
return ;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)rsrc_entries, count * sizeof(struct rsrc_entries_s));
#endif
for(i=0; i<count; i++)
{
const struct rsrc_entries_s *rsrc_entry=&rsrc_entries[i];
const unsigned int rsrcType=le32(rsrc_entry->Type);
#ifdef DEBUG_EXE
log_info("resource type=%u, %x, offset %u\n",
rsrcType,
le32(rsrc_entry->Pos),
base + (le32(rsrc_entry->Pos) & 0x7fffffff));
#endif
/* https://docs.microsoft.com/en-us/windows/win32/menurc/resource-types
* RT_CURSOR=1, RT_ICON=3, RT_VERSION=16 */
/* Only interested by version resources */
if(rsrcType==16)
{
if((le32(rsrc_entry->Pos) & 0x80000000)!=0)
{
pe_resource_id(file,
base,
le32(rsrc_entry->Pos) & 0x7fffffff,
pe_sections, nbr_sections, file_recovery);
}
}
}
free(rsrc_entries);
}
/*@
@ requires \valid(file_recovery);
@ requires valid_read_string((char*)&file_recovery->filename);
@ requires file_recovery->file_rename==&file_rename_pe_exe;
@*/
static void file_rename_pe_exe(file_recovery_t *file_recovery)
{
unsigned char buffer[4096];
FILE *file;
int buffer_size;
const struct dos_image_file_hdr *dos_hdr;
const struct pe_image_file_hdr *pe_hdr;
unsigned int e_lfanew;
if((file=fopen(file_recovery->filename, "rb"))==NULL)
return;
buffer_size=fread(buffer, 1, sizeof(buffer), file);
/*@ assert buffer_size <= sizeof(buffer); */
if(buffer_size < (int)sizeof(struct dos_image_file_hdr))
{
fclose(file);
return ;
}
/*@ assert buffer_size >= sizeof(struct dos_image_file_hdr); */
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)buffer, sizeof(buffer));
#endif
if(memcmp(buffer,exe_header,sizeof(exe_header))!=0)
{
fclose(file);
return ;
}
dos_hdr=(const struct dos_image_file_hdr*)buffer;
e_lfanew=le32(dos_hdr->e_lfanew);
if((unsigned int)buffer_size < e_lfanew+sizeof(struct pe_image_file_hdr))
{
fclose(file);
return ;
}
if(e_lfanew==0 ||
e_lfanew > buffer_size-sizeof(struct pe_image_file_hdr))
{
fclose(file);
return ;
}
pe_hdr=(const struct pe_image_file_hdr *)(buffer+e_lfanew);
if(le32(pe_hdr->Magic) != IMAGE_NT_SIGNATURE)
{
fclose(file);
return ;
}
{
const uint64_t offset_sections=e_lfanew + sizeof(struct pe_image_file_hdr) + le16(pe_hdr->SizeOfOptionalHeader);
/* https://docs.microsoft.com/en-us/windows/win32/debug/pe-format
* Windows loader limits the number of sections to 96
*/
const unsigned int nbr_sections=(le16(pe_hdr->NumberOfSections) < 96?le16(pe_hdr->NumberOfSections) : 96);
struct pe_image_section_hdr pe_sections[96];
unsigned int i;
if(nbr_sections == 0)
{
fclose(file);
return ;
}
/*@ assert 0 < nbr_sections <= 96; */
if(fseek(file, offset_sections, SEEK_SET)<0)
{
fclose(file);
return ;
}
if(fread(pe_sections, sizeof(struct pe_image_section_hdr), nbr_sections, file) != nbr_sections)
{
fclose(file);
return ;
}
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)pe_sections, sizeof(pe_sections));
#endif
#ifdef DEBUG_EXE
/*@
@ loop invariant 0 <= i <= nbr_sections;
@*/
for(i=0; i<nbr_sections; i++)
{
const struct pe_image_section_hdr *pe_section=&pe_sections[i];
/*@ assert \valid_read(pe_section); */
if(le32(pe_section->VirtualSize)>0)
{
log_info("%s 0x%lx-0x%lx\n", pe_section->Name,
(unsigned long)le32(pe_section->VirtualAddress),
(unsigned long)le32(pe_section->VirtualAddress)+le32(pe_section->VirtualSize)-1);
}
}
#endif
/*@
@ loop invariant 0 <= i <= nbr_sections;
@*/
for(i=0; i<nbr_sections; i++)
{
const struct pe_image_section_hdr *pe_section=&pe_sections[i];
/*@ assert \valid_read(pe_section); */
if(le32(pe_section->SizeOfRawData)>0)
{
if(memcmp((const char*)pe_section->Name, ".rsrc", 6)==0)
{
pe_resource_type(file,
le32(pe_section->PointerToRawData),
le32(pe_section->SizeOfRawData),
pe_sections, nbr_sections, file_recovery);
fclose(file);
return;
}
}
}
}
fclose(file);
}
/*@
@ requires buffer_size >= 2;
@ requires \valid_read(buffer+(0..buffer_size-1));
@ requires \valid_read(file_recovery);
@ requires file_recovery->file_stat==\null || valid_read_string((char*)file_recovery->filename);
@ requires \valid(file_recovery_new);
@ requires file_recovery_new->blocksize > 0;
@ requires separation: \separated(&file_hint_exe, buffer+(..), file_recovery, file_recovery_new);
@ ensures \result == 0 || \result == 1;
@ ensures (\result == 1) ==> (file_recovery_new->file_stat == \null);
@ ensures (\result == 1) ==> (file_recovery_new->handle == \null);
@ ensures (\result == 1) ==> (file_recovery_new->extension == file_hint_exe.extension || file_recovery_new->extension == extension_dll);
@ ensures (\result == 1) ==> (file_recovery_new->data_check == \null || file_recovery_new->data_check == &data_check_size);
@ ensures (\result == 1) ==> (file_recovery_new->file_check == \null || file_recovery_new->file_check == &file_check_size);
@ ensures (\result == 1) ==> (file_recovery_new->file_rename == \null || file_recovery_new->file_rename == &file_rename_pe_exe);
@ ensures (\result == 1) ==> (valid_read_string(file_recovery_new->extension));
@ ensures (\result == 1) ==> \separated(file_recovery_new, file_recovery_new->extension);
@ ensures \result!=0 ==> valid_file_recovery(file_recovery_new);
@ assigns *file_recovery_new;
@*/
static int header_check_exe(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)
{
const struct dos_image_file_hdr *dos_hdr=(const struct dos_image_file_hdr*)buffer;
if(memcmp(buffer,exe_header,sizeof(exe_header))!=0)
return 0;
if(le32(dos_hdr->e_lfanew)>0 &&
le32(dos_hdr->e_lfanew) <= buffer_size-sizeof(struct pe_image_file_hdr))
{
const struct pe_image_file_hdr *pe_hdr=(const struct pe_image_file_hdr *)(buffer+le32(dos_hdr->e_lfanew));
if((le32(pe_hdr->Magic) & 0xffff) == IMAGE_WIN16_SIGNATURE)
{
/* NE Win16 */
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_exe.extension;
file_recovery_new->min_filesize=le32(dos_hdr->e_lfanew) + sizeof(struct pe_image_file_hdr);
return 1;
}
if((le32(pe_hdr->Magic) & 0xffff) == IMAGE_NT_SIGNATURE)
{
/* Windows PE */
if(le16(pe_hdr->Characteristics) & 0x2000)
{
/* Dynamic Link Library */
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=extension_dll;
}
else if(le16(pe_hdr->Characteristics) & 0x02)
{
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_exe.extension;
}
else
{
#ifdef DEBUG_EXE
log_warning("EXE rejected, bad characteristics %02x\n", le16(pe_hdr->Characteristics));
#endif
return 0;
}
file_recovery_new->time=le32(pe_hdr->TimeDateStamp);
#ifdef DEBUG_EXE
{
const struct pe_image_optional_hdr32 *pe_image_optional32=(const struct pe_image_optional_hdr32 *)
(((const unsigned char*)pe_hdr + sizeof(struct pe_image_file_hdr)));
if((const unsigned char*)(pe_image_optional32+1) <= buffer+buffer_size)
{
/*@ assert \valid_read(pe_image_optional32); */
if(le16(pe_image_optional32->Magic)==IMAGE_NT_OPTIONAL_HDR_MAGIC)
{
log_debug("SizeOfCode %lx\n", (long unsigned)le32(pe_image_optional32->SizeOfCode));
log_debug("SizeOfImage %lx\n", (long unsigned)le32(pe_image_optional32->SizeOfImage));
}
else if(le16(pe_image_optional32->Magic)==IMAGE_NT_OPTIONAL_HDR64_MAGIC)
{
const struct pe_image_optional_hdr64 *pe_image_optional64=(const struct pe_image_optional_hdr64 *)
(((const unsigned char*)pe_hdr + sizeof(struct pe_image_file_hdr)));
}
log_debug("PE image opt 0x%lx-0x%lx\n", (long unsigned)sizeof(struct pe_image_file_hdr),
(long unsigned)(sizeof(struct pe_image_file_hdr) + le16(pe_hdr->SizeOfOptionalHeader) - 1));
}
}
#endif
{
unsigned int i;
uint64_t sum=le32(dos_hdr->e_lfanew) + sizeof(struct pe_image_file_hdr);
const struct pe_image_section_hdr *pe_image_section=(const struct pe_image_section_hdr*)
((const unsigned char*)pe_hdr + sizeof(struct pe_image_file_hdr) + le16(pe_hdr->SizeOfOptionalHeader));
/*@
@ loop assigns i, pe_image_section, sum;
@*/
for(i=0;
i<le16(pe_hdr->NumberOfSections) &&
(const unsigned char*)(pe_image_section+1) <= buffer+buffer_size;
i++,pe_image_section++)
{
if(le32(pe_image_section->SizeOfRawData)>0)
{
const uint64_t tmp=(uint64_t)le32(pe_image_section->PointerToRawData) + le32(pe_image_section->SizeOfRawData);
#ifdef DEBUG_EXE
log_debug("%s 0x%lx-0x%lx\n", pe_image_section->Name,
(unsigned long)le32(pe_image_section->PointerToRawData),
(unsigned long)(tmp-1));
#endif
if(le32(pe_image_section->SizeOfRawData)%32==0)
{
if(sum < tmp)
sum=tmp;
}
}
if(le16(pe_image_section->NumberOfRelocations)>0)
{
/*@ assert le16(pe_image_section->NumberOfRelocations)>0; */
const uint64_t tmp=(uint64_t)le32(pe_image_section->PointerToRelocations)+ 1*le16(pe_image_section->NumberOfRelocations);
/*@ assert tmp > 0; */
#ifdef DEBUG_EXE
log_debug("relocations 0x%lx-0x%lx\n",
(unsigned long)le32(pe_image_section->PointerToRelocations),
(unsigned long)(tmp-1));
#endif
if(sum < tmp)
sum = tmp;
}
}
if(le32(pe_hdr->NumberOfSymbols)>0)
{
/*@ assert le32(pe_hdr->NumberOfSymbols)>0; */
const uint64_t tmp=(uint64_t)le32(pe_hdr->PointerToSymbolTable)+ IMAGE_SIZEOF_SYMBOL*(uint64_t)le32(pe_hdr->NumberOfSymbols);
/*@ assert tmp > 0; */
#ifdef DEBUG_EXE
log_debug("Symboles 0x%lx-0x%lx\n", (long unsigned)le32(pe_hdr->PointerToSymbolTable),
(long unsigned)(tmp-1));
#endif
if(le32(pe_hdr->NumberOfSymbols)<0x10000)
{
if(sum < tmp)
sum = tmp;
}
}
/* It's not perfect, EXE overlay are not recovered */
file_recovery_new->calculated_file_size=sum;
}
file_recovery_new->data_check=&data_check_size;
file_recovery_new->file_check=&file_check_size;
file_recovery_new->file_rename=&file_rename_pe_exe;
return 1;
}
}
if(le16(dos_hdr->bytes_in_last_block) <= 512 &&
le16(dos_hdr->blocks_in_file) > 0 &&
le16(dos_hdr->min_extra_paragraphs) <= le16(dos_hdr->max_extra_paragraphs)
)
{
/* MSDOS EXE */
uint64_t coff_offset=le16(dos_hdr->blocks_in_file)*512;
if(le16(dos_hdr->bytes_in_last_block))
coff_offset-=512-le16(dos_hdr->bytes_in_last_block);
if(coff_offset < buffer_size-1 &&
buffer[coff_offset]==0x4c && buffer[coff_offset+1]==0x01)
{ /* COFF_I386MAGIC */
reset_file_recovery(file_recovery_new);
file_recovery_new->extension=file_hint_exe.extension;
file_recovery_new->min_filesize=coff_offset+2;
return 1;
}
#ifdef DEBUG_EXE
{
const struct exe_reloc *exe_relocs;
const unsigned int reloc_table_offset=le16(dos_hdr->reloc_table_offset);
const unsigned int num_relocs=le16(dos_hdr->num_relocs);
log_info("Maybe a DOS EXE\n");
log_info("blocks %llu\n", (long long unsigned)coff_offset);
log_info("data start %llx\n", (long long unsigned)16*le16(dos_hdr->header_paragraphs));
log_info("reloc %u\n", num_relocs);
if(reloc_table_offset + num_relocs * sizeof(struct exe_reloc) <= buffer_size)
{
unsigned int i;
/*@ assert reloc_table_offset + num_relocs * sizeof(struct exe_reloc) <= buffer_size; */
exe_relocs=(const struct exe_reloc *)(buffer+reloc_table_offset);
/*@ assert \valid_read(exe_relocs + (0 .. num_relocs-1)); */
/*@
@ loop invariant 0 <= i <= num_relocs;
@ loop variant num_relocs -i;
@ */
for(i=0; i < num_relocs; i++)
{
/*@ assert 0 <= i <= num_relocs; */
const struct exe_reloc *exe_reloc=&exe_relocs[i];
/*@ assert \valid_read(exe_reloc); */
log_info("offset %x, segment %x\n",
le16(exe_reloc->offset), le16(exe_reloc->segment));
}
}
}
#endif
}
return 0;
}
static void register_header_check_exe(file_stat_t *file_stat)
{
register_header_check(0, exe_header,sizeof(exe_header), &header_check_exe, file_stat);
}
#endif
#if defined(MAIN_exe)
#define BLOCKSIZE 65536u
int main()
{
const char fn[] = "recup_dir.1/f0000000.exe";
unsigned char buffer[BLOCKSIZE];
file_recovery_t file_recovery_new;
file_recovery_t file_recovery;
file_stat_t file_stats;
/*@ assert \valid(buffer + (0 .. (BLOCKSIZE - 1))); */
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)buffer, BLOCKSIZE);
#endif
reset_file_recovery(&file_recovery);
file_recovery.blocksize=BLOCKSIZE;
file_recovery_new.blocksize=BLOCKSIZE;
file_recovery_new.data_check=NULL;
file_recovery_new.file_stat=NULL;
file_recovery_new.file_check=NULL;
file_recovery_new.file_rename=NULL;
file_recovery_new.calculated_file_size=0;
file_recovery_new.file_size=0;
file_recovery_new.location.start=0;
file_stats.file_hint=&file_hint_exe;
file_stats.not_recovered=0;
file_stats.recovered=0;
register_header_check_exe(&file_stats);
if(header_check_exe(buffer, BLOCKSIZE, 0u, &file_recovery, &file_recovery_new)!=1)
return 0;
/*@ assert valid_read_string((char *)&fn); */
memcpy(file_recovery_new.filename, fn, sizeof(fn));
/*@ assert valid_read_string((char *)&file_recovery_new.filename); */
/*@ assert file_recovery_new.file_size == 0; */
/*@ assert file_recovery_new.extension == file_hint_exe.extension || file_recovery_new.extension == extension_dll; */
file_recovery_new.file_stat=&file_stats;
if(file_recovery_new.file_stat!=NULL && file_recovery_new.file_stat->file_hint!=NULL &&
file_recovery_new.data_check!=NULL)
{
unsigned char big_buffer[2*BLOCKSIZE];
data_check_t res_data_check=DC_CONTINUE;
memset(big_buffer, 0, BLOCKSIZE);
memcpy(big_buffer + BLOCKSIZE, buffer, BLOCKSIZE);
/*@ assert file_recovery_new.data_check == &data_check_size; */
/*@ assert file_recovery_new.file_size == 0; */;
res_data_check=data_check_size(big_buffer, 2*BLOCKSIZE, &file_recovery_new);
file_recovery_new.file_size+=BLOCKSIZE;
if(res_data_check == DC_CONTINUE)
{
memcpy(big_buffer, big_buffer + BLOCKSIZE, BLOCKSIZE);
#if defined(__FRAMAC__)
Frama_C_make_unknown((char *)big_buffer + BLOCKSIZE, BLOCKSIZE);
#endif
data_check_size(big_buffer, 2*BLOCKSIZE, &file_recovery_new);
}
}
if(file_recovery_new.file_stat!=NULL)
{
file_recovery_t file_recovery_new2;
/* Test when another file of the same is detected in the next block */
file_recovery_new2.blocksize=BLOCKSIZE;
file_recovery_new2.file_stat=NULL;
file_recovery_new2.file_check=NULL;
file_recovery_new2.location.start=BLOCKSIZE;
file_recovery_new.handle=NULL; /* In theory should be not null */
header_check_exe(buffer, BLOCKSIZE, 0, &file_recovery_new, &file_recovery_new2);
}
if(file_recovery_new.file_check!=NULL)
{
/*@ assert file_recovery_new.file_check == &file_check_size; */
file_recovery_new.handle=fopen(fn, "rb");
if(file_recovery_new.handle!=NULL)
{
file_check_size(&file_recovery_new);
fclose(file_recovery_new.handle);
}
}
if(file_recovery_new.file_rename!=NULL)
{
/*@ assert valid_read_string((char *)&file_recovery_new.filename); */
/*@ assert file_recovery_new.file_rename == &file_rename_pe_exe; */
file_rename_pe_exe(&file_recovery_new);
}
return 0;
}
#endif