1 /*
2 
3     File: file_woff.c
4 
5     Copyright (C) 2014 Christophe GRENIER <grenier@cgsecurity.org>
6 
7     This software is free software; you can redistribute it and/or modify
8     it under the terms of the GNU General Public License as published by
9     the Free Software Foundation; either version 2 of the License, or
10     (at your option) any later version.
11 
12     This program is distributed in the hope that it will be useful,
13     but WITHOUT ANY WARRANTY; without even the implied warranty of
14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15     GNU General Public License for more details.
16 
17     You should have received a copy of the GNU General Public License along
18     with this program; if not, write the Free Software Foundation, Inc., 51
19     Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 
21  */
22 
23 #ifdef HAVE_CONFIG_H
24 #include <config.h>
25 #endif
26 #ifdef HAVE_STRING_H
27 #include <string.h>
28 #endif
29 #include <stdio.h>
30 #include "types.h"
31 #include "filegen.h"
32 #include "common.h"
33 
34 static void register_header_check_woff(file_stat_t *file_stat);
35 
36 const file_hint_t file_hint_woff= {
37   .extension="woff",
38   .description="Web Open Font Format",
39   .max_filesize=PHOTOREC_MAX_FILE_SIZE,
40   .recover=1,
41   .enable_by_default=1,
42   .register_header_check=&register_header_check_woff
43 };
44 
45 struct WOFFHeader
46 {
47   uint32_t	signature;
48   uint32_t	flavor;
49   uint32_t	length;
50   uint16_t	numTables;
51   uint16_t	reserved;
52   uint32_t	totalSfntSize;
53   uint16_t	majorVersion;
54   uint16_t	minorVersion;
55   uint32_t	metaOffset;
56   uint32_t	metaLength;
57   uint32_t	metaOrigLength;
58   uint32_t	privOffset;
59   uint32_t	privLength;
60 } __attribute__ ((gcc_struct, __packed__));
61 
header_check_woff(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)62 static int header_check_woff(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)
63 {
64   const struct WOFFHeader *woff=(const struct WOFFHeader *)buffer;
65   const uint64_t length=(uint64_t)be32(woff->length);
66   if((uint32_t)be32(woff->length) < sizeof(struct WOFFHeader))
67     return 0;
68   if((uint32_t)be32(woff->metaOffset) > 0 && (uint32_t)be32(woff->metaOffset) < sizeof(struct WOFFHeader))
69     return 0;
70   if((uint32_t)be32(woff->privOffset) > 0 && (uint32_t)be32(woff->privOffset) < sizeof(struct WOFFHeader))
71     return 0;
72   if((uint64_t)be32(woff->metaOffset) + (uint64_t)be32(woff->metaLength) > length ||
73       (uint64_t)be32(woff->privOffset) + (uint64_t)be32(woff->privLength) > length)
74     return 0;
75   if(woff->reserved!=0)
76     return 0;
77   reset_file_recovery(file_recovery_new);
78   file_recovery_new->extension=file_hint_woff.extension;
79   file_recovery_new->calculated_file_size=length;
80   file_recovery_new->data_check=&data_check_size;
81   file_recovery_new->file_check=&file_check_size;
82   return 1;
83 }
84 
register_header_check_woff(file_stat_t * file_stat)85 static void register_header_check_woff(file_stat_t *file_stat)
86 {
87   register_header_check(0, "wOFF", 4, &header_check_woff, file_stat);
88 }
89