1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
/*
File: file_ps.c
Copyright (C) 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_ps)
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <stdio.h>
#include "types.h"
#include "filegen.h"
#include "common.h"
/*@ requires \valid(file_stat); */
static void register_header_check_ps(file_stat_t *file_stat);
static data_check_t data_check_ps(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery);
const file_hint_t file_hint_ps= {
.extension="ps",
.description="PostScript or Encapsulated PostScript document",
.max_filesize=PHOTOREC_MAX_FILE_SIZE,
.recover=1,
.enable_by_default=1,
.register_header_check=®ister_header_check_ps
};
static const unsigned char ps_header[11]= { '%','!','P','S','-','A','d','o','b','e','-'};
/*@
@ requires \valid(file_recovery);
@ requires \valid(file_recovery->handle);
@ requires valid_file_recovery(file_recovery);
@ requires \separated(file_recovery, file_recovery->handle, file_recovery->extension, &errno, &Frama_C_entropy_source);
@ ensures \valid(file_recovery->handle);
@ ensures valid_file_recovery(file_recovery);
@ assigns *file_recovery->handle, errno, file_recovery->file_size;
@ assigns Frama_C_entropy_source;
@*/
static void file_check_ps(file_recovery_t *file_recovery)
{
const unsigned char ps_footer[5]="%%EOF";
file_search_footer(file_recovery, ps_footer, sizeof(ps_footer), 1);
}
/*@
@ requires buffer_size > 8;
@ requires (buffer_size&1)==0;
@ requires \valid_read(buffer+(0..buffer_size-1));
@ requires \valid(file_recovery);
@ requires file_recovery->data_check==&data_check_ps;
@ requires file_recovery->calculated_file_size <= PHOTOREC_MAX_FILE_SIZE;
@ requires \separated(buffer, file_recovery);
@ ensures \result == DC_CONTINUE || \result == DC_STOP;
@ assigns file_recovery->calculated_file_size;
@*/
static data_check_t data_check_ps(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
unsigned int i;
/*@
@ loop assigns i, file_recovery->calculated_file_size;
@*/
for(i=(buffer_size/2)-4;i+4<buffer_size;i++)
{
if(buffer[i]=='%' && buffer[i+1]=='%' && buffer[i+2]=='E' && buffer[i+3]=='O' && buffer[i+4]=='F')
{
file_recovery->calculated_file_size=file_recovery->file_size+i+5-(buffer_size/2);
return DC_STOP;
}
}
file_recovery->calculated_file_size=file_recovery->file_size+(buffer_size/2);
return DC_CONTINUE;
}
/*@
@ requires buffer_size > 0;
@ requires \valid_read(buffer+(0..buffer_size-1));
@ requires valid_file_recovery(file_recovery);
@ requires \valid(file_recovery_new);
@ requires file_recovery_new->blocksize > 0;
@ requires separation: \separated(&file_hint_ps, buffer+(..), file_recovery, file_recovery_new);
@ assigns *file_recovery_new;
@ ensures \result!=0 ==> valid_file_recovery(file_recovery_new);
@*/
static int header_check_ps(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)
{
/* PS or EPSF */
int i;
reset_file_recovery(file_recovery_new);
file_recovery_new->min_filesize=sizeof(ps_header);
file_recovery_new->file_check=&file_check_ps;
/*@ loop assigns i, file_recovery_new->extension, file_recovery_new->data_check; */
for(i=sizeof(ps_header); i < 20; i++)
{
switch(buffer[i])
{
case '\n':
file_recovery_new->extension=file_hint_ps.extension;
if(file_recovery_new->blocksize > 8)
file_recovery_new->data_check=&data_check_ps;
return 1;
case 'E':
if(i+5 <= buffer_size && memcmp(&buffer[i],"EPSF-",5)==0)
{
file_recovery_new->extension="eps";
return 1;
}
break;
}
}
file_recovery_new->extension=file_hint_ps.extension;
if(file_recovery_new->blocksize > 8)
file_recovery_new->data_check=&data_check_ps;
return 1;
}
static void register_header_check_ps(file_stat_t *file_stat)
{
register_header_check(0, ps_header,sizeof(ps_header), &header_check_ps, file_stat);
}
#endif
|
