util-linux/volume_id/iso9660.c

   1 /*
   2  * volume_id - reads filesystem label and uuid
   3  *
   4  * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  *      This library is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU Lesser General Public
   8  *      License as published by the Free Software Foundation; either
   9  *      version 2.1 of the License, or (at your option) any later version.
  10  *
  11  *      This library is distributed in the hope that it will be useful,
  12  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  *      Lesser General Public License for more details.
  15  *
  16  *      You should have received a copy of the GNU Lesser General Public
  17  *      License along with this library; if not, write to the Free Software
  18  *      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  */
  20
  21 //kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_ISO9660) += iso9660.o
  22
  23 //config:
  24 //config:config FEATURE_VOLUMEID_ISO9660
  25 //config:       bool "iso9660 filesystem"
  26 //config:       default y
  27 //config:       depends on VOLUMEID
  28 //config:       help
  29 //config:         TODO
  30 //config:
  31
  32 #include "volume_id_internal.h"
  33
  34 #define ISO_SUPERBLOCK_OFFSET           0x8000
  35 #define ISO_SECTOR_SIZE                 0x800
  36 #define ISO_VD_OFFSET                   (ISO_SUPERBLOCK_OFFSET + ISO_SECTOR_SIZE)
  37 #define ISO_VD_PRIMARY                  0x1
  38 #define ISO_VD_SUPPLEMENTARY            0x2
  39 #define ISO_VD_END                      0xff
  40 #define ISO_VD_MAX                      16
  41
  42 struct iso_volume_descriptor {
  43         uint8_t         vd_type;
  44         uint8_t         vd_id[5];
  45         uint8_t         vd_version;
  46         uint8_t         flags;
  47         uint8_t         system_id[32];
  48         uint8_t         volume_id[32];
  49         uint8_t         unused[8];
  50         uint8_t         space_size[8];
  51         uint8_t         escape_sequences[8];
  52 } PACKED;
  53
  54 struct high_sierra_volume_descriptor {
  55         uint8_t         foo[8];
  56         uint8_t         type;
  57         uint8_t         id[4];
  58         uint8_t         version;
  59 } PACKED;
  60
  61 int FAST_FUNC volume_id_probe_iso9660(struct volume_id *id /*,uint64_t off*/)
  62 {
  63 #define off ((uint64_t)0)
  64         uint8_t *buf;
  65         struct iso_volume_descriptor *is;
  66         struct high_sierra_volume_descriptor *hs;
  67
  68         dbg("probing at offset 0x%llx", (unsigned long long) off);
  69
  70         buf = volume_id_get_buffer(id, off + ISO_SUPERBLOCK_OFFSET, 0x200);
  71         if (buf == NULL)
  72                 return -1;
  73
  74         is = (struct iso_volume_descriptor *) buf;
  75
  76         if (memcmp(is->vd_id, "CD001", 5) == 0) {
  77                 int vd_offset;
  78                 int i;
  79
  80                 dbg("read label from PVD");
  81 //              volume_id_set_label_raw(id, is->volume_id, 32);
  82                 volume_id_set_label_string(id, is->volume_id, 32);
  83
  84                 dbg("looking for SVDs");
  85                 vd_offset = ISO_VD_OFFSET;
  86                 for (i = 0; i < ISO_VD_MAX; i++) {
  87                         uint8_t svd_label[64];
  88
  89                         is = volume_id_get_buffer(id, off + vd_offset, 0x200);
  90                         if (is == NULL || is->vd_type == ISO_VD_END)
  91                                 break;
  92                         if (is->vd_type != ISO_VD_SUPPLEMENTARY)
  93                                 continue;
  94
  95                         dbg("found SVD at offset 0x%llx", (unsigned long long) (off + vd_offset));
  96                         if (memcmp(is->escape_sequences, "%/@", 3) == 0
  97                          || memcmp(is->escape_sequences, "%/C", 3) == 0
  98                          || memcmp(is->escape_sequences, "%/E", 3) == 0
  99                         ) {
 100                                 dbg("Joliet extension found");
 101                                 volume_id_set_unicode16((char *)svd_label, sizeof(svd_label), is->volume_id, BE, 32);
 102                                 if (memcmp(id->label, svd_label, 16) == 0) {
 103                                         dbg("SVD label is identical, use the possibly longer PVD one");
 104                                         break;
 105                                 }
 106
 107 //                              volume_id_set_label_raw(id, is->volume_id, 32);
 108                                 volume_id_set_label_string(id, svd_label, 32);
 109 //                              strcpy(id->type_version, "Joliet Extension");
 110                                 goto found;
 111                         }
 112                         vd_offset += ISO_SECTOR_SIZE;
 113                 }
 114                 goto found;
 115         }
 116
 117         hs = (struct high_sierra_volume_descriptor *) buf;
 118
 119         if (memcmp(hs->id, "CDROM", 5) == 0) {
 120 //              strcpy(id->type_version, "High Sierra");
 121                 goto found;
 122         }
 123
 124         return -1;
 125
 126  found:
 127 //      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 128         IF_FEATURE_BLKID_TYPE(id->type = "iso9660";)
 129
 130         return 0;
 131 }