util-linux/volume_id/hfs.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_HFS) += hfs.o
  22
  23 //config:config FEATURE_VOLUMEID_HFS
  24 //config:       bool "hfs filesystem"
  25 //config:       default y
  26 //config:       depends on VOLUMEID
  27
  28 #include "volume_id_internal.h"
  29
  30 struct hfs_finder_info{
  31         uint32_t        boot_folder;
  32         uint32_t        start_app;
  33         uint32_t        open_folder;
  34         uint32_t        os9_folder;
  35         uint32_t        reserved;
  36         uint32_t        osx_folder;
  37         uint8_t         id[8];
  38 } PACKED;
  39
  40 struct hfs_mdb {
  41         uint8_t         signature[2];
  42         uint32_t        cr_date;
  43         uint32_t        ls_Mod;
  44         uint16_t        atrb;
  45         uint16_t        nm_fls;
  46         uint16_t        vbm_st;
  47         uint16_t        alloc_ptr;
  48         uint16_t        nm_al_blks;
  49         uint32_t        al_blk_size;
  50         uint32_t        clp_size;
  51         uint16_t        al_bl_st;
  52         uint32_t        nxt_cnid;
  53         uint16_t        free_bks;
  54         uint8_t         label_len;
  55         uint8_t         label[27];
  56         uint32_t        vol_bkup;
  57         uint16_t        vol_seq_num;
  58         uint32_t        wr_cnt;
  59         uint32_t        xt_clump_size;
  60         uint32_t        ct_clump_size;
  61         uint16_t        num_root_dirs;
  62         uint32_t        file_count;
  63         uint32_t        dir_count;
  64         struct hfs_finder_info finder_info;
  65         uint8_t         embed_sig[2];
  66         uint16_t        embed_startblock;
  67         uint16_t        embed_blockcount;
  68 } PACKED;
  69
  70 struct hfsplus_bnode_descriptor {
  71         uint32_t        next;
  72         uint32_t        prev;
  73         uint8_t         type;
  74         uint8_t         height;
  75         uint16_t        num_recs;
  76         uint16_t        reserved;
  77 } PACKED;
  78
  79 struct hfsplus_bheader_record {
  80         uint16_t        depth;
  81         uint32_t        root;
  82         uint32_t        leaf_count;
  83         uint32_t        leaf_head;
  84         uint32_t        leaf_tail;
  85         uint16_t        node_size;
  86 } PACKED;
  87
  88 struct hfsplus_catalog_key {
  89         uint16_t        key_len;
  90         uint32_t        parent_id;
  91         uint16_t        unicode_len;
  92         uint8_t         unicode[255 * 2];
  93 } PACKED;
  94
  95 struct hfsplus_extent {
  96         uint32_t        start_block;
  97         uint32_t        block_count;
  98 } PACKED;
  99
 100 #define HFSPLUS_EXTENT_COUNT            8
 101 struct hfsplus_fork {
 102         uint64_t        total_size;
 103         uint32_t        clump_size;
 104         uint32_t        total_blocks;
 105         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
 106 } PACKED;
 107
 108 struct hfsplus_vol_header {
 109         uint8_t         signature[2];
 110         uint16_t        version;
 111         uint32_t        attributes;
 112         uint32_t        last_mount_vers;
 113         uint32_t        reserved;
 114         uint32_t        create_date;
 115         uint32_t        modify_date;
 116         uint32_t        backup_date;
 117         uint32_t        checked_date;
 118         uint32_t        file_count;
 119         uint32_t        folder_count;
 120         uint32_t        blocksize;
 121         uint32_t        total_blocks;
 122         uint32_t        free_blocks;
 123         uint32_t        next_alloc;
 124         uint32_t        rsrc_clump_sz;
 125         uint32_t        data_clump_sz;
 126         uint32_t        next_cnid;
 127         uint32_t        write_count;
 128         uint64_t        encodings_bmp;
 129         struct hfs_finder_info finder_info;
 130         struct hfsplus_fork alloc_file;
 131         struct hfsplus_fork ext_file;
 132         struct hfsplus_fork cat_file;
 133         struct hfsplus_fork attr_file;
 134         struct hfsplus_fork start_file;
 135 } PACKED;
 136
 137 #define HFS_SUPERBLOCK_OFFSET           0x400
 138 #define HFS_NODE_LEAF                   0xff
 139 #define HFSPLUS_POR_CNID                1
 140
 141 static void FAST_FUNC hfs_set_uuid(struct volume_id *id, const uint8_t *hfs_id)
 142 {
 143 #define hfs_id_len 8
 144         md5_ctx_t md5c;
 145         uint8_t uuid[16];
 146         unsigned i;
 147
 148         for (i = 0; i < hfs_id_len; i++)
 149                 if (hfs_id[i] != 0)
 150                         goto do_md5;
 151         return;
 152  do_md5:
 153         md5_begin(&md5c);
 154         md5_hash(&md5c, "\263\342\17\71\362\222\21\326\227\244\0\60\145\103\354\254", 16);
 155         md5_hash(&md5c, hfs_id, hfs_id_len);
 156         md5_end(&md5c, uuid);
 157         uuid[6] = 0x30 | (uuid[6] & 0x0f);
 158         uuid[8] = 0x80 | (uuid[8] & 0x3f);
 159         volume_id_set_uuid(id, uuid, UUID_DCE);
 160 }
 161
 162 int FAST_FUNC volume_id_probe_hfs_hfsplus(struct volume_id *id /*,uint64_t off*/)
 163 {
 164         uint64_t off = 0;
 165         unsigned blocksize;
 166         unsigned cat_block;
 167         unsigned ext_block_start;
 168         unsigned ext_block_count;
 169         int ext;
 170         unsigned leaf_node_head;
 171         unsigned leaf_node_count;
 172         unsigned leaf_node_size;
 173         unsigned leaf_block;
 174         uint64_t leaf_off;
 175         unsigned alloc_block_size;
 176         unsigned alloc_first_block;
 177         unsigned embed_first_block;
 178         unsigned record_count;
 179         struct hfsplus_vol_header *hfsplus;
 180         struct hfsplus_bnode_descriptor *descr;
 181         struct hfsplus_bheader_record *bnode;
 182         struct hfsplus_catalog_key *key;
 183         unsigned label_len;
 184         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
 185         struct hfs_mdb *hfs;
 186         const uint8_t *buf;
 187
 188         dbg("probing at offset 0x%llx", (unsigned long long) off);
 189
 190         buf = volume_id_get_buffer(id, off + HFS_SUPERBLOCK_OFFSET, 0x200);
 191         if (buf == NULL)
 192                 return -1;
 193
 194         hfs = (struct hfs_mdb *) buf;
 195         if (hfs->signature[0] != 'B' || hfs->signature[1] != 'D')
 196                 goto checkplus;
 197
 198         /* it may be just a hfs wrapper for hfs+ */
 199         if (hfs->embed_sig[0] == 'H' && hfs->embed_sig[1] == '+') {
 200                 alloc_block_size = be32_to_cpu(hfs->al_blk_size);
 201                 dbg("alloc_block_size 0x%x", alloc_block_size);
 202
 203                 alloc_first_block = be16_to_cpu(hfs->al_bl_st);
 204                 dbg("alloc_first_block 0x%x", alloc_first_block);
 205
 206                 embed_first_block = be16_to_cpu(hfs->embed_startblock);
 207                 dbg("embed_first_block 0x%x", embed_first_block);
 208
 209                 off += (alloc_first_block * 512) +
 210                        (embed_first_block * alloc_block_size);
 211                 dbg("hfs wrapped hfs+ found at offset 0x%llx", (unsigned long long) off);
 212
 213                 buf = volume_id_get_buffer(id, off + HFS_SUPERBLOCK_OFFSET, 0x200);
 214                 if (buf == NULL)
 215                         return -1;
 216                 goto checkplus;
 217         }
 218
 219         if (hfs->label_len > 0 && hfs->label_len < 28) {
 220 //              volume_id_set_label_raw(id, hfs->label, hfs->label_len);
 221                 volume_id_set_label_string(id, hfs->label, hfs->label_len) ;
 222         }
 223
 224         hfs_set_uuid(id, hfs->finder_info.id);
 225 //      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 226         IF_FEATURE_BLKID_TYPE(id->type = "hfs";)
 227
 228         return 0;
 229
 230  checkplus:
 231         hfsplus = (struct hfsplus_vol_header *) buf;
 232         if (hfs->signature[0] == 'H')
 233                 if (hfs->signature[1] == '+' || hfs->signature[1] == 'X')
 234                         goto hfsplus;
 235         return -1;
 236
 237  hfsplus:
 238         hfs_set_uuid(id, hfsplus->finder_info.id);
 239
 240         blocksize = be32_to_cpu(hfsplus->blocksize);
 241         dbg("blocksize %u", blocksize);
 242
 243         memcpy(extents, hfsplus->cat_file.extents, sizeof(extents));
 244         cat_block = be32_to_cpu(extents[0].start_block);
 245         dbg("catalog start block 0x%x", cat_block);
 246
 247         buf = volume_id_get_buffer(id, off + (cat_block * blocksize), 0x2000);
 248         if (buf == NULL)
 249                 goto found;
 250
 251         bnode = (struct hfsplus_bheader_record *)
 252                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 253
 254         leaf_node_head = be32_to_cpu(bnode->leaf_head);
 255         dbg("catalog leaf node 0x%x", leaf_node_head);
 256
 257         leaf_node_size = be16_to_cpu(bnode->node_size);
 258         dbg("leaf node size 0x%x", leaf_node_size);
 259
 260         leaf_node_count = be32_to_cpu(bnode->leaf_count);
 261         dbg("leaf node count 0x%x", leaf_node_count);
 262         if (leaf_node_count == 0)
 263                 goto found;
 264
 265         leaf_block = (leaf_node_head * leaf_node_size) / blocksize;
 266
 267         /* get physical location */
 268         for (ext = 0; ext < HFSPLUS_EXTENT_COUNT; ext++) {
 269                 ext_block_start = be32_to_cpu(extents[ext].start_block);
 270                 ext_block_count = be32_to_cpu(extents[ext].block_count);
 271                 dbg("extent start block 0x%x, count 0x%x", ext_block_start, ext_block_count);
 272
 273                 if (ext_block_count == 0)
 274                         goto found;
 275
 276                 /* this is our extent */
 277                 if (leaf_block < ext_block_count)
 278                         break;
 279
 280                 leaf_block -= ext_block_count;
 281         }
 282         if (ext == HFSPLUS_EXTENT_COUNT)
 283                 goto found;
 284         dbg("found block in extent %i", ext);
 285
 286         leaf_off = (ext_block_start + leaf_block) * blocksize;
 287
 288         buf = volume_id_get_buffer(id, off + leaf_off, leaf_node_size);
 289         if (buf == NULL)
 290                 goto found;
 291
 292         descr = (struct hfsplus_bnode_descriptor *) buf;
 293         dbg("descriptor type 0x%x", descr->type);
 294
 295         record_count = be16_to_cpu(descr->num_recs);
 296         dbg("number of records %u", record_count);
 297         if (record_count == 0)
 298                 goto found;
 299
 300         if (descr->type != HFS_NODE_LEAF)
 301                 goto found;
 302
 303         key = (struct hfsplus_catalog_key *)
 304                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 305
 306         dbg("parent id 0x%x", be32_to_cpu(key->parent_id));
 307         if (key->parent_id != cpu_to_be32(HFSPLUS_POR_CNID))
 308                 goto found;
 309
 310         label_len = be16_to_cpu(key->unicode_len) * 2;
 311         dbg("label unicode16 len %i", label_len);
 312 //      volume_id_set_label_raw(id, key->unicode, label_len);
 313         volume_id_set_label_unicode16(id, key->unicode, BE, label_len);
 314
 315  found:
 316 //      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 317         IF_FEATURE_BLKID_TYPE(id->type = "hfsplus";)
 318
 319         return 0;
 320 }