2 * volume_id - reads filesystem label and uuid
4 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation version 2 of the License.
26 #include "volume_id.h"
31 #define ISO_SUPERBLOCK_OFFSET 0x8000
32 #define ISO_SECTOR_SIZE 0x800
33 #define ISO_VD_OFFSET (ISO_SUPERBLOCK_OFFSET + ISO_SECTOR_SIZE)
34 #define ISO_VD_PRIMARY 0x1
35 #define ISO_VD_SUPPLEMENTARY 0x2
36 #define ISO_VD_END 0xff
39 struct iso_volume_descriptor {
44 uint8_t system_id[32];
45 uint8_t volume_id[32];
47 uint8_t space_size[8];
48 uint8_t escape_sequences[8];
49 } __attribute__((__packed__));
51 struct high_sierra_volume_descriptor {
56 } __attribute__((__packed__));
58 int volume_id_probe_iso9660(struct volume_id *id, uint64_t off)
61 struct iso_volume_descriptor *is;
62 struct high_sierra_volume_descriptor *hs;
64 dbg("probing at offset 0x%llx", (unsigned long long) off);
66 buf = volume_id_get_buffer(id, off + ISO_SUPERBLOCK_OFFSET, 0x200);
70 is = (struct iso_volume_descriptor *) buf;
72 if (memcmp(is->vd_id, "CD001", 5) == 0) {
76 dbg("read label from PVD");
77 volume_id_set_label_raw(id, is->volume_id, 32);
78 volume_id_set_label_string(id, is->volume_id, 32);
80 dbg("looking for SVDs");
81 vd_offset = ISO_VD_OFFSET;
82 for (i = 0; i < ISO_VD_MAX; i++) {
83 uint8_t svd_label[64];
85 is = (struct iso_volume_descriptor *) volume_id_get_buffer(id, off + vd_offset, 0x200);
86 if (is == NULL || is->vd_type == ISO_VD_END)
88 if (is->vd_type != ISO_VD_SUPPLEMENTARY)
91 dbg("found SVD at offset 0x%llx", (unsigned long long) (off + vd_offset));
92 if (memcmp(is->escape_sequences, "%/@", 3) == 0||
93 memcmp(is->escape_sequences, "%/C", 3) == 0||
94 memcmp(is->escape_sequences, "%/E", 3) == 0) {
95 dbg("Joliet extension found");
96 volume_id_set_unicode16((char *)svd_label, sizeof(svd_label), is->volume_id, BE, 32);
97 if (memcmp(id->label, svd_label, 16) == 0) {
98 dbg("SVD label is identical, use the possibly longer PVD one");
102 volume_id_set_label_raw(id, is->volume_id, 32);
103 volume_id_set_label_string(id, svd_label, 32);
104 strcpy(id->type_version, "Joliet Extension");
107 vd_offset += ISO_SECTOR_SIZE;
112 hs = (struct high_sierra_volume_descriptor *) buf;
114 if (memcmp(hs->id, "CDROM", 5) == 0) {
115 strcpy(id->type_version, "High Sierra");
122 volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
123 id->type = "iso9660";