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