summaryrefslogtreecommitdiffstats
path: root/src/file_gz.c
diff options
context:
space:
mode:
authorChristophe Grenier <grenier@cgsecurity.org>2007-10-29 22:38:52 +0100
committerChristophe Grenier <grenier@cgsecurity.org>2007-10-29 22:38:52 +0100
commit9928d99936105b4653d2d1b8ca74dc3ffba5c71e (patch)
tree06aa4f5e9f0055027c6fb54dd47a8414cf2fba32 /src/file_gz.c
First version in git
Diffstat (limited to 'src/file_gz.c')
-rw-r--r--src/file_gz.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/src/file_gz.c b/src/file_gz.c
new file mode 100644
index 0000000..0dd64a2
--- /dev/null
+++ b/src/file_gz.c
@@ -0,0 +1,71 @@
+/*
+
+ File: file_gz.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
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#include <stdio.h>
+#include "types.h"
+#include "filegen.h"
+
+static void register_header_check_gz(file_stat_t *file_stat);
+static int header_check_gz(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 file_hint_t file_hint_gz= {
+ .extension="gz",
+ .description="gzip compressed data",
+ .min_header_distance=0,
+ .max_filesize=PHOTOREC_MAX_FILE_SIZE,
+ .recover=1,
+ .header_check=&header_check_gz,
+ .register_header_check=&register_header_check_gz
+};
+
+static const unsigned char gz_header[3]= {0x1F, 0x8B, 0x08};
+
+static void register_header_check_gz(file_stat_t *file_stat)
+{
+ register_header_check(0, gz_header,sizeof(gz_header), &header_check_gz, file_stat);
+}
+
+static int header_check_gz(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)
+{
+ /* gzip file format:
+ * a 10-byte header, containing a magic number, a version number and a timestamp
+ * optional extra headers, such as the original file name,
+ * a body, containing a deflate-compressed payload
+ * a CRC-32 checksum
+ * the length (32 bits) of the original uncompressed data
+ */
+ /* gzip, deflate */
+ if(buffer[0]==0x1F && buffer[1]==0x8B && buffer[2]==0x08 && (buffer[3]&0xe0)==0)
+ {
+ reset_file_recovery(file_recovery_new);
+ file_recovery_new->extension=file_hint_gz.extension;
+ file_recovery_new->min_filesize=22;
+ return 1;
+ }
+ return 0;
+}