vcs.maemo.org Git - busybox4maemo/blob - 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 #include "volume_id_internal.h"
  22
  23 struct hfs_finder_info{
  24         uint32_t        boot_folder;
  25         uint32_t        start_app;
  26         uint32_t        open_folder;
  27         uint32_t        os9_folder;
  28         uint32_t        reserved;
  29         uint32_t        osx_folder;
  30         uint8_t         id[8];
  31 } __attribute__((__packed__));
  32
  33 struct hfs_mdb {
  34         uint8_t         signature[2];
  35         uint32_t        cr_date;
  36         uint32_t        ls_Mod;
  37         uint16_t        atrb;
  38         uint16_t        nm_fls;
  39         uint16_t        vbm_st;
  40         uint16_t        alloc_ptr;
  41         uint16_t        nm_al_blks;
  42         uint32_t        al_blk_size;
  43         uint32_t        clp_size;
  44         uint16_t        al_bl_st;
  45         uint32_t        nxt_cnid;
  46         uint16_t        free_bks;
  47         uint8_t         label_len;
  48         uint8_t         label[27];
  49         uint32_t        vol_bkup;
  50         uint16_t        vol_seq_num;
  51         uint32_t        wr_cnt;
  52         uint32_t        xt_clump_size;
  53         uint32_t        ct_clump_size;
  54         uint16_t        num_root_dirs;
  55         uint32_t        file_count;
  56         uint32_t        dir_count;
  57         struct hfs_finder_info finder_info;
  58         uint8_t         embed_sig[2];
  59         uint16_t        embed_startblock;
  60         uint16_t        embed_blockcount;
  61 } __attribute__((__packed__));
  62
  63 struct hfsplus_bnode_descriptor {
  64         uint32_t        next;
  65         uint32_t        prev;
  66         uint8_t         type;
  67         uint8_t         height;
  68         uint16_t        num_recs;
  69         uint16_t        reserved;
  70 } __attribute__((__packed__));
  71
  72 struct hfsplus_bheader_record {
  73         uint16_t        depth;
  74         uint32_t        root;
  75         uint32_t        leaf_count;
  76         uint32_t        leaf_head;
  77         uint32_t        leaf_tail;
  78         uint16_t        node_size;
  79 } __attribute__((__packed__));
  80
  81 struct hfsplus_catalog_key {
  82         uint16_t        key_len;
  83         uint32_t        parent_id;
  84         uint16_t        unicode_len;
  85         uint8_t         unicode[255 * 2];
  86 } __attribute__((__packed__));
  87
  88 struct hfsplus_extent {
  89         uint32_t        start_block;
  90         uint32_t        block_count;
  91 } __attribute__((__packed__));
  92
  93 #define HFSPLUS_EXTENT_COUNT            8
  94 struct hfsplus_fork {
  95         uint64_t        total_size;
  96         uint32_t        clump_size;
  97         uint32_t        total_blocks;
  98         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
  99 } __attribute__((__packed__));
 100
 101 struct hfsplus_vol_header {
 102         uint8_t         signature[2];
 103         uint16_t        version;
 104         uint32_t        attributes;
 105         uint32_t        last_mount_vers;
 106         uint32_t        reserved;
 107         uint32_t        create_date;
 108         uint32_t        modify_date;
 109         uint32_t        backup_date;
 110         uint32_t        checked_date;
 111         uint32_t        file_count;
 112         uint32_t        folder_count;
 113         uint32_t        blocksize;
 114         uint32_t        total_blocks;
 115         uint32_t        free_blocks;
 116         uint32_t        next_alloc;
 117         uint32_t        rsrc_clump_sz;
 118         uint32_t        data_clump_sz;
 119         uint32_t        next_cnid;
 120         uint32_t        write_count;
 121         uint64_t        encodings_bmp;
 122         struct hfs_finder_info finder_info;
 123         struct hfsplus_fork alloc_file;
 124         struct hfsplus_fork ext_file;
 125         struct hfsplus_fork cat_file;
 126         struct hfsplus_fork attr_file;
 127         struct hfsplus_fork start_file;
 128 } __attribute__((__packed__));
 129
 130 #define HFS_SUPERBLOCK_OFFSET           0x400
 131 #define HFS_NODE_LEAF                   0xff
 132 #define HFSPLUS_POR_CNID                1
 133
 134 int volume_id_probe_hfs_hfsplus(struct volume_id *id, uint64_t off)
 135 {
 136         unsigned blocksize;
 137         unsigned cat_block;
 138         unsigned ext_block_start;
 139         unsigned ext_block_count;
 140         int ext;
 141         unsigned leaf_node_head;
 142         unsigned leaf_node_count;
 143         unsigned leaf_node_size;
 144         unsigned leaf_block;
 145         uint64_t leaf_off;
 146         unsigned alloc_block_size;
 147         unsigned alloc_first_block;
 148         unsigned embed_first_block;
 149         unsigned record_count;
 150         struct hfsplus_vol_header *hfsplus;
 151         struct hfsplus_bnode_descriptor *descr;
 152         struct hfsplus_bheader_record *bnode;
 153         struct hfsplus_catalog_key *key;
 154         unsigned label_len;
 155         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
 156         struct hfs_mdb *hfs;
 157         const uint8_t *buf;
 158
 159         dbg("probing at offset 0x%llx", (unsigned long long) off);
 160
 161         buf = volume_id_get_buffer(id, off + HFS_SUPERBLOCK_OFFSET, 0x200);
 162         if (buf == NULL)
 163                 return -1;
 164
 165         hfs = (struct hfs_mdb *) buf;
 166         if (hfs->signature[0] != 'B' || hfs->signature[1] != 'D')
 167                 goto checkplus;
 168
 169         /* it may be just a hfs wrapper for hfs+ */
 170         if (hfs->embed_sig[0] == 'H' && hfs->embed_sig[1] == '+') {
 171                 alloc_block_size = be32_to_cpu(hfs->al_blk_size);
 172                 dbg("alloc_block_size 0x%x", alloc_block_size);
 173
 174                 alloc_first_block = be16_to_cpu(hfs->al_bl_st);
 175                 dbg("alloc_first_block 0x%x", alloc_first_block);
 176
 177                 embed_first_block = be16_to_cpu(hfs->embed_startblock);
 178                 dbg("embed_first_block 0x%x", embed_first_block);
 179
 180                 off += (alloc_first_block * 512) +
 181                        (embed_first_block * alloc_block_size);
 182                 dbg("hfs wrapped hfs+ found at offset 0x%llx", (unsigned long long) off);
 183
 184                 buf = volume_id_get_buffer(id, off + HFS_SUPERBLOCK_OFFSET, 0x200);
 185                 if (buf == NULL)
 186                         return -1;
 187                 goto checkplus;
 188         }
 189
 190         if (hfs->label_len > 0 && hfs->label_len < 28) {
 191 //              volume_id_set_label_raw(id, hfs->label, hfs->label_len);
 192                 volume_id_set_label_string(id, hfs->label, hfs->label_len) ;
 193         }
 194
 195         volume_id_set_uuid(id, hfs->finder_info.id, UUID_HFS);
 196 //      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 197 //      id->type = "hfs";
 198
 199         return 0;
 200
 201  checkplus:
 202         hfsplus = (struct hfsplus_vol_header *) buf;
 203         if (hfs->signature[0] == 'H')
 204                 if (hfs->signature[1] == '+' || hfs->signature[1] == 'X')
 205                         goto hfsplus;
 206         return -1;
 207
 208  hfsplus:
 209         volume_id_set_uuid(id, hfsplus->finder_info.id, UUID_HFS);
 210
 211         blocksize = be32_to_cpu(hfsplus->blocksize);
 212         dbg("blocksize %u", blocksize);
 213
 214         memcpy(extents, hfsplus->cat_file.extents, sizeof(extents));
 215         cat_block = be32_to_cpu(extents[0].start_block);
 216         dbg("catalog start block 0x%x", cat_block);
 217
 218         buf = volume_id_get_buffer(id, off + (cat_block * blocksize), 0x2000);
 219         if (buf == NULL)
 220                 goto found;
 221
 222         bnode = (struct hfsplus_bheader_record *)
 223                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 224
 225         leaf_node_head = be32_to_cpu(bnode->leaf_head);
 226         dbg("catalog leaf node 0x%x", leaf_node_head);
 227
 228         leaf_node_size = be16_to_cpu(bnode->node_size);
 229         dbg("leaf node size 0x%x", leaf_node_size);
 230
 231         leaf_node_count = be32_to_cpu(bnode->leaf_count);
 232         dbg("leaf node count 0x%x", leaf_node_count);
 233         if (leaf_node_count == 0)
 234                 goto found;
 235
 236         leaf_block = (leaf_node_head * leaf_node_size) / blocksize;
 237
 238         /* get physical location */
 239         for (ext = 0; ext < HFSPLUS_EXTENT_COUNT; ext++) {
 240                 ext_block_start = be32_to_cpu(extents[ext].start_block);
 241                 ext_block_count = be32_to_cpu(extents[ext].block_count);
 242                 dbg("extent start block 0x%x, count 0x%x", ext_block_start, ext_block_count);
 243
 244                 if (ext_block_count == 0)
 245                         goto found;
 246
 247                 /* this is our extent */
 248                 if (leaf_block < ext_block_count)
 249                         break;
 250
 251                 leaf_block -= ext_block_count;
 252         }
 253         if (ext == HFSPLUS_EXTENT_COUNT)
 254                 goto found;
 255         dbg("found block in extent %i", ext);
 256
 257         leaf_off = (ext_block_start + leaf_block) * blocksize;
 258
 259         buf = volume_id_get_buffer(id, off + leaf_off, leaf_node_size);
 260         if (buf == NULL)
 261                 goto found;
 262
 263         descr = (struct hfsplus_bnode_descriptor *) buf;
 264         dbg("descriptor type 0x%x", descr->type);
 265
 266         record_count = be16_to_cpu(descr->num_recs);
 267         dbg("number of records %u", record_count);
 268         if (record_count == 0)
 269                 goto found;
 270
 271         if (descr->type != HFS_NODE_LEAF)
 272                 goto found;
 273
 274         key = (struct hfsplus_catalog_key *)
 275                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 276
 277         dbg("parent id 0x%x", be32_to_cpu(key->parent_id));
 278         if (key->parent_id != cpu_to_be32(HFSPLUS_POR_CNID))
 279                 goto found;
 280
 281         label_len = be16_to_cpu(key->unicode_len) * 2;
 282         dbg("label unicode16 len %i", label_len);
 283 //      volume_id_set_label_raw(id, key->unicode, label_len);
 284         volume_id_set_label_unicode16(id, key->unicode, BE, label_len);
 285
 286  found:
 287 //      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 288 //      id->type = "hfsplus";
 289
 290         return 0;
 291 }