From 1739339385ca8e02bf7827bdc4c9004f67e967b6 Mon Sep 17 00:00:00 2001
From: Christophe Grenier <grenier@cgsecurity.org>
Date: Wed, 2 Apr 2008 23:58:10 +0200
Subject: [PATCH] PhotoRec: detect .iso filesize

---
 src/file_iso.c | 64 ++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 51 insertions(+), 13 deletions(-)

diff --git a/src/file_iso.c b/src/file_iso.c
index 50ec62c6..6783f657 100644
--- a/src/file_iso.c
+++ b/src/file_iso.c
@@ -30,13 +30,12 @@
 #include "types.h"
 #include "filegen.h"
 
-
 static void register_header_check_iso(file_stat_t *file_stat);
 static int header_check_db(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_iso= {
   .extension="iso",
-  .description="ISO (Only detected if block size >= 64k)",
+  .description="ISO",
   .min_header_distance=0,
   .max_filesize=PHOTOREC_MAX_FILE_SIZE,
   .recover=1,
@@ -44,30 +43,69 @@ const file_hint_t file_hint_iso= {
   .register_header_check=&register_header_check_iso
 };
 
-
 static const unsigned char iso_header[6]= { 0x01, 'C', 'D', '0', '0', '1'};
-/* ISO 9660
-   0x00 Volume Descriptor Type		0x01
-   0x01 Standard Identifier 		CD001
-   0x07 Volume Descriptor Version	0x01
-   0x08 Unused Field			0x00
-   0x09 System Identifier
-   0x41 Volume Identifier
-   0x73 Unused Field
-*/
+
 static void register_header_check_iso(file_stat_t *file_stat)
 {
   register_header_check(0x8000, iso_header,sizeof(iso_header), &header_check_db, file_stat);
 }
 
+struct iso_primary_descriptor
+{
+	char type;
+	char id[5];
+	char version;
+	char unused1;
+	char system_id[32];
+	char volume_id[32];
+	char unused2[8];
+	char volume_space_size[8];
+	char unused3[32];
+	char volume_set_size[4];
+	char volume_sequence_number[4];
+	char logical_block_size[4];
+	char path_table_size[8];
+	char type_l_path_tabl[4];
+	char opt_type_l_path_table[4];
+	char type_m_path_table[4];
+	char opt_type_m_path_table[4];
+	char root_directory_record[34];
+	char volume_set_id[128];
+	char publisher_id[128];
+	char preparer_id[128];
+	char application_id[128];
+	char copyright_file_id[37];
+	char abstract_file_id[37];
+	char bibliographic_file_id[37];
+	char creation_date[17];
+	char modification_date[17];
+	char expiration_date[17];
+	char effective_date[17];
+	char file_structure_version;
+	char unused4;
+	char application_data[512];
+	char unused5[653];
+} __attribute__ ((__packed__));
+
 static int header_check_db(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)
 {
-  if(buffer_size<0x8000+sizeof(iso_header))
+  if(buffer_size<0x8000+512)	/* +2048 for the full mapping */
     return 0;
   if(memcmp (&buffer[0x8000], iso_header, sizeof(iso_header))==0)
   {
+    const struct iso_primary_descriptor *iso1=(const struct iso_primary_descriptor*)&buffer[0x8000];
+    const unsigned int volume_space_size=iso1->volume_space_size[0] | (iso1->volume_space_size[1]<<8) | (iso1->volume_space_size[2]<<16) | (iso1->volume_space_size[3]<<24);
+    const unsigned int volume_space_size2=iso1->volume_space_size[7] | (iso1->volume_space_size[6]<<8) | (iso1->volume_space_size[5]<<16) | (iso1->volume_space_size[4]<<24);
+    const unsigned int logical_block_size=iso1->logical_block_size[0] | (iso1->logical_block_size[1]<<8);
+    const unsigned int logical_block_size2=iso1->logical_block_size[3] | (iso1->logical_block_size[2]<<8);
     reset_file_recovery(file_recovery_new);
     file_recovery_new->extension=file_hint_iso.extension;
+    if(volume_space_size==volume_space_size2 && logical_block_size==logical_block_size2)
+    {	/* ISO 9660 */
+      file_recovery_new->calculated_file_size=(uint64_t)volume_space_size * logical_block_size;
+      file_recovery_new->data_check=&data_check_size;
+      file_recovery_new->file_check=&file_check_size;
+    }
     return 1;
   }
   return 0;