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:
  24 //config:config FEATURE_VOLUMEID_HFS
  25 //config:       bool "hfs 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 struct hfs_finder_info{
  35         uint32_t        boot_folder;
  36         uint32_t        start_app;
  37         uint32_t        open_folder;
  38         uint32_t        os9_folder;
  39         uint32_t        reserved;
  40         uint32_t        osx_folder;
  41         uint8_t         id[8];
  42 } PACKED;
  43
  44 struct hfs_mdb {
  45         uint8_t         signature[2];
  46         uint32_t        cr_date;
  47         uint32_t        ls_Mod;
  48         uint16_t        atrb;
  49         uint16_t        nm_fls;
  50         uint16_t        vbm_st;
  51         uint16_t        alloc_ptr;
  52         uint16_t        nm_al_blks;
  53         uint32_t        al_blk_size;
  54         uint32_t        clp_size;
  55         uint16_t        al_bl_st;
  56         uint32_t        nxt_cnid;
  57         uint16_t        free_bks;
  58         uint8_t         label_len;
  59         uint8_t         label[27];
  60         uint32_t        vol_bkup;
  61         uint16_t        vol_seq_num;
  62         uint32_t        wr_cnt;
  63         uint32_t        xt_clump_size;
  64         uint32_t        ct_clump_size;
  65         uint16_t        num_root_dirs;
  66         uint32_t        file_count;
  67         uint32_t        dir_count;
  68         struct hfs_finder_info finder_info;
  69         uint8_t         embed_sig[2];
  70         uint16_t        embed_startblock;
  71         uint16_t        embed_blockcount;
  72 } PACKED;
  73
  74 struct hfsplus_bnode_descriptor {
  75         uint32_t        next;
  76         uint32_t        prev;
  77         uint8_t         type;
  78         uint8_t         height;
  79         uint16_t        num_recs;
  80         uint16_t        reserved;
  81 } PACKED;
  82
  83 struct hfsplus_bheader_record {
  84         uint16_t        depth;
  85         uint32_t        root;
  86         uint32_t        leaf_count;
  87         uint32_t        leaf_head;
  88         uint32_t        leaf_tail;
  89         uint16_t        node_size;
  90 } PACKED;
  91
  92 struct hfsplus_catalog_key {
  93         uint16_t        key_len;
  94         uint32_t        parent_id;
  95         uint16_t        unicode_len;
  96         uint8_t         unicode[255 * 2];
  97 } PACKED;
  98
  99 struct hfsplus_extent {
 100         uint32_t        start_block;
 101         uint32_t        block_count;
 102 } PACKED;
 103
 104 #define HFSPLUS_EXTENT_COUNT            8
 105 struct hfsplus_fork {
 106         uint64_t        total_size;
 107         uint32_t        clump_size;
 108         uint32_t        total_blocks;
 109         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
 110 } PACKED;
 111
 112 struct hfsplus_vol_header {
 113         uint8_t         signature[2];
 114         uint16_t        version;
 115         uint32_t        attributes;
 116         uint32_t        last_mount_vers;
 117         uint32_t        reserved;
 118         uint32_t        create_date;
 119         uint32_t        modify_date;
 120         uint32_t        backup_date;
 121         uint32_t        checked_date;
 122         uint32_t        file_count;
 123         uint32_t        folder_count;
 124         uint32_t        blocksize;
 125         uint32_t        total_blocks;
 126         uint32_t        free_blocks;
 127         uint32_t        next_alloc;
 128         uint32_t        rsrc_clump_sz;
 129         uint32_t        data_clump_sz;
 130         uint32_t        next_cnid;
 131         uint32_t        write_count;
 132         uint64_t        encodings_bmp;
 133         struct hfs_finder_info finder_info;
 134         struct hfsplus_fork alloc_file;
 135         struct hfsplus_fork ext_file;
 136         struct hfsplus_fork cat_file;
 137         struct hfsplus_fork attr_file;
 138         struct hfsplus_fork start_file;
 139 } PACKED;
 140
 141 #define HFS_SUPERBLOCK_OFFSET           0x400
 142 #define HFS_NODE_LEAF                   0xff
 143 #define HFSPLUS_POR_CNID                1
 144
 145 static void FAST_FUNC hfs_set_uuid(struct volume_id *id, const uint8_t *hfs_id)
 146 {
 147 #define hfs_id_len 8
 148         md5_ctx_t md5c;
 149         uint8_t uuid[16];
 150         unsigned i;
 151
 152         for (i = 0; i < hfs_id_len; i++)
 153                 if (hfs_id[i] != 0)
 154                         goto do_md5;
 155         return;
 156  do_md5:
 157         md5_begin(&md5c);
 158         md5_hash(&md5c, "\263\342\17\71\362\222\21\326\227\244\0\60\145\103\354\254", 16);
 159         md5_hash(&md5c, hfs_id, hfs_id_len);
 160         md5_end(&md5c, uuid);
 161         uuid[6] = 0x30 | (uuid[6] & 0x0f);
 162         uuid[8] = 0x80 | (uuid[8] & 0x3f);
 163         volume_id_set_uuid(id, uuid, UUID_DCE);
 164 }
 165
 166 int FAST_FUNC volume_id_probe_hfs_hfsplus(struct volume_id *id /*,uint64_t off*/)
 167 {
 168         uint64_t off = 0;
 169         unsigned blocksize;
 170         unsigned cat_block;
 171         unsigned ext_block_start;
 172         unsigned ext_block_count;
 173         int ext;
 174         unsigned leaf_node_head;
 175         unsigned leaf_node_count;
 176         unsigned leaf_node_size;
 177         unsigned leaf_block;
 178         uint64_t leaf_off;
 179         unsigned alloc_block_size;
 180         unsigned alloc_first_block;
 181         unsigned embed_first_block;
 182         unsigned record_count;
 183         struct hfsplus_vol_header *hfsplus;
 184         struct hfsplus_bnode_descriptor *descr;
 185         struct hfsplus_bheader_record *bnode;
 186         struct hfsplus_catalog_key *key;
 187         unsigned label_len;
 188         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
 189         struct hfs_mdb *hfs;
 190         const uint8_t *buf;
 191
 192         dbg("probing at offset 0x%llx", (unsigned long long) off);
 193
 194         buf = volume_id_get_buffer(id, off + HFS_SUPERBLOCK_OFFSET, 0x200);
 195         if (buf == NULL)
 196                 return -1;
 197
 198         hfs = (struct hfs_mdb *) buf;
 199         if (hfs->signature[0] != 'B' || hfs->signature[1] != 'D')
 200                 goto checkplus;
 201
 202         /* it may be just a hfs wrapper for hfs+ */
 203         if (hfs->embed_sig[0] == 'H' && hfs->embed_sig[1] == '+') {
 204                 alloc_block_size = be32_to_cpu(hfs->al_blk_size);
 205                 dbg("alloc_block_size 0x%x", alloc_block_size);
 206
 207                 alloc_first_block = be16_to_cpu(hfs->al_bl_st);
 208                 dbg("alloc_first_block 0x%x", alloc_first_block);
 209
 210                 embed_first_block = be16_to_cpu(hfs->embed_startblock);
 211                 dbg("embed_first_block 0x%x", embed_first_block);
 212
 213                 off += (alloc_first_block * 512) +
 214                        (embed_first_block * alloc_block_size);
 215                 dbg("hfs wrapped hfs+ found at offset 0x%llx", (unsigned long long) off);
 216
 217                 buf = volume_id_get_buffer(id, off + HFS_SUPERBLOCK_OFFSET, 0x200);
 218                 if (buf == NULL)
 219                         return -1;
 220                 goto checkplus;
 221         }
 222
 223         if (hfs->label_len > 0 && hfs->label_len < 28) {
 224 //              volume_id_set_label_raw(id, hfs->label, hfs->label_len);
 225                 volume_id_set_label_string(id, hfs->label, hfs->label_len) ;
 226         }
 227
 228         hfs_set_uuid(id, hfs->finder_info.id);
 229 //      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 230         IF_FEATURE_BLKID_TYPE(id->type = "hfs";)
 231
 232         return 0;
 233
 234  checkplus:
 235         hfsplus = (struct hfsplus_vol_header *) buf;
 236         if (hfs->signature[0] == 'H')
 237                 if (hfs->signature[1] == '+' || hfs->signature[1] == 'X')
 238                         goto hfsplus;
 239         return -1;
 240
 241  hfsplus:
 242         hfs_set_uuid(id, hfsplus->finder_info.id);
 243
 244         blocksize = be32_to_cpu(hfsplus->blocksize);
 245         dbg("blocksize %u", blocksize);
 246
 247         memcpy(extents, hfsplus->cat_file.extents, sizeof(extents));
 248         cat_block = be32_to_cpu(extents[0].start_block);
 249         dbg("catalog start block 0x%x", cat_block);
 250
 251         buf = volume_id_get_buffer(id, off + (cat_block * blocksize), 0x2000);
 252         if (buf == NULL)
 253                 goto found;
 254
 255         bnode = (struct hfsplus_bheader_record *)
 256                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 257
 258         leaf_node_head = be32_to_cpu(bnode->leaf_head);
 259         dbg("catalog leaf node 0x%x", leaf_node_head);
 260
 261         leaf_node_size = be16_to_cpu(bnode->node_size);
 262         dbg("leaf node size 0x%x", leaf_node_size);
 263
 264         leaf_node_count = be32_to_cpu(bnode->leaf_count);
 265         dbg("leaf node count 0x%x", leaf_node_count);
 266         if (leaf_node_count == 0)
 267                 goto found;
 268
 269         leaf_block = (leaf_node_head * leaf_node_size) / blocksize;
 270
 271         /* get physical location */
 272         for (ext = 0; ext < HFSPLUS_EXTENT_COUNT; ext++) {
 273                 ext_block_start = be32_to_cpu(extents[ext].start_block);
 274                 ext_block_count = be32_to_cpu(extents[ext].block_count);
 275                 dbg("extent start block 0x%x, count 0x%x", ext_block_start, ext_block_count);
 276
 277                 if (ext_block_count == 0)
 278                         goto found;
 279
 280                 /* this is our extent */
 281                 if (leaf_block < ext_block_count)
 282                         break;
 283
 284                 leaf_block -= ext_block_count;
 285         }
 286         if (ext == HFSPLUS_EXTENT_COUNT)
 287                 goto found;
 288         dbg("found block in extent %i", ext);
 289
 290         leaf_off = (ext_block_start + leaf_block) * blocksize;
 291
 292         buf = volume_id_get_buffer(id, off + leaf_off, leaf_node_size);
 293         if (buf == NULL)
 294                 goto found;
 295
 296         descr = (struct hfsplus_bnode_descriptor *) buf;
 297         dbg("descriptor type 0x%x", descr->type);
 298
 299         record_count = be16_to_cpu(descr->num_recs);
 300         dbg("number of records %u", record_count);
 301         if (record_count == 0)
 302                 goto found;
 303
 304         if (descr->type != HFS_NODE_LEAF)
 305                 goto found;
 306
 307         key = (struct hfsplus_catalog_key *)
 308                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 309
 310         dbg("parent id 0x%x", be32_to_cpu(key->parent_id));
 311         if (key->parent_id != cpu_to_be32(HFSPLUS_POR_CNID))
 312                 goto found;
 313
 314         label_len = be16_to_cpu(key->unicode_len) * 2;
 315         dbg("label unicode16 len %i", label_len);
 316 //      volume_id_set_label_raw(id, key->unicode, label_len);
 317         volume_id_set_label_unicode16(id, key->unicode, BE, label_len);
 318
 319  found:
 320 //      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 321         IF_FEATURE_BLKID_TYPE(id->type = "hfsplus";)
 322
 323         return 0;
 324 }