shlibs/blkid/src/probers/hfs.c

   1 /*
   2  * Copyright (C) 2004-2008 Kay Sievers <kay.sievers@vrfy.org>
   3  * Copyright (C) 2008 Karel Zak <kzak@redhat.com>
   4  *
   5  * This file may be redistributed under the terms of the
   6  * GNU Lesser General Public License.
   7  */
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11 #include <string.h>
  12 #include <inttypes.h>
  13
  14 #include "blkidP.h"
  15 #include "md5.h"
  16
  17 /* HFS / HFS+ */
  18 struct hfs_finder_info {
  19         uint32_t        boot_folder;
  20         uint32_t        start_app;
  21         uint32_t        open_folder;
  22         uint32_t        os9_folder;
  23         uint32_t        reserved;
  24         uint32_t        osx_folder;
  25         uint8_t         id[8];
  26 } __attribute__((packed));
  27
  28 struct hfs_mdb {
  29         uint8_t         signature[2];
  30         uint32_t        cr_date;
  31         uint32_t        ls_Mod;
  32         uint16_t        atrb;
  33         uint16_t        nm_fls;
  34         uint16_t        vbm_st;
  35         uint16_t        alloc_ptr;
  36         uint16_t        nm_al_blks;
  37         uint32_t        al_blk_size;
  38         uint32_t        clp_size;
  39         uint16_t        al_bl_st;
  40         uint32_t        nxt_cnid;
  41         uint16_t        free_bks;
  42         uint8_t         label_len;
  43         uint8_t         label[27];
  44         uint32_t        vol_bkup;
  45         uint16_t        vol_seq_num;
  46         uint32_t        wr_cnt;
  47         uint32_t        xt_clump_size;
  48         uint32_t        ct_clump_size;
  49         uint16_t        num_root_dirs;
  50         uint32_t        file_count;
  51         uint32_t        dir_count;
  52         struct hfs_finder_info finder_info;
  53         uint8_t         embed_sig[2];
  54         uint16_t        embed_startblock;
  55         uint16_t        embed_blockcount;
  56 } __attribute__((packed));
  57
  58
  59 #define HFS_NODE_LEAF                   0xff
  60 #define HFSPLUS_POR_CNID                1
  61
  62 struct hfsplus_bnode_descriptor {
  63         uint32_t                next;
  64         uint32_t                prev;
  65         uint8_t         type;
  66         uint8_t         height;
  67         uint16_t                num_recs;
  68         uint16_t                reserved;
  69 } __attribute__((packed));
  70
  71 struct hfsplus_bheader_record {
  72         uint16_t                depth;
  73         uint32_t                root;
  74         uint32_t                leaf_count;
  75         uint32_t                leaf_head;
  76         uint32_t                leaf_tail;
  77         uint16_t                node_size;
  78 } __attribute__((packed));
  79
  80 struct hfsplus_catalog_key {
  81         uint16_t        key_len;
  82         uint32_t        parent_id;
  83         uint16_t        unicode_len;
  84         uint8_t         unicode[255 * 2];
  85 } __attribute__((packed));
  86
  87 struct hfsplus_extent {
  88         uint32_t                start_block;
  89         uint32_t                block_count;
  90 } __attribute__((packed));
  91
  92 #define HFSPLUS_EXTENT_COUNT            8
  93 struct hfsplus_fork {
  94         uint64_t                total_size;
  95         uint32_t                clump_size;
  96         uint32_t                total_blocks;
  97         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
  98 } __attribute__((packed));
  99
 100 struct hfsplus_vol_header {
 101         uint8_t         signature[2];
 102         uint16_t                version;
 103         uint32_t                attributes;
 104         uint32_t                last_mount_vers;
 105         uint32_t                reserved;
 106         uint32_t                create_date;
 107         uint32_t                modify_date;
 108         uint32_t                backup_date;
 109         uint32_t                checked_date;
 110         uint32_t                file_count;
 111         uint32_t                folder_count;
 112         uint32_t                blocksize;
 113         uint32_t                total_blocks;
 114         uint32_t                free_blocks;
 115         uint32_t                next_alloc;
 116         uint32_t                rsrc_clump_sz;
 117         uint32_t                data_clump_sz;
 118         uint32_t                next_cnid;
 119         uint32_t                write_count;
 120         uint64_t                encodings_bmp;
 121         struct hfs_finder_info finder_info;
 122         struct hfsplus_fork alloc_file;
 123         struct hfsplus_fork ext_file;
 124         struct hfsplus_fork cat_file;
 125         struct hfsplus_fork attr_file;
 126         struct hfsplus_fork start_file;
 127 }  __attribute__((packed));
 128
 129 static int hfs_set_uuid(blkid_probe pr, unsigned char const *hfs_info, size_t len)
 130 {
 131         static unsigned char const hash_init[16] = {
 132                 0xb3, 0xe2, 0x0f, 0x39, 0xf2, 0x92, 0x11, 0xd6,
 133                 0x97, 0xa4, 0x00, 0x30, 0x65, 0x43, 0xec, 0xac
 134         };
 135         unsigned char uuid[16];
 136         struct MD5Context md5c;
 137
 138         if (memcmp(hfs_info, "\0\0\0\0\0\0\0\0", len) == 0)
 139                 return -1;
 140         MD5Init(&md5c);
 141         MD5Update(&md5c, hash_init, 16);
 142         MD5Update(&md5c, hfs_info, len);
 143         MD5Final(uuid, &md5c);
 144         uuid[6] = 0x30 | (uuid[6] & 0x0f);
 145         uuid[8] = 0x80 | (uuid[8] & 0x3f);
 146         return blkid_probe_set_uuid(pr, uuid);
 147 }
 148
 149 static int probe_hfs(blkid_probe pr, const struct blkid_idmag *mag)
 150 {
 151         struct hfs_mdb  *hfs;
 152
 153         hfs = blkid_probe_get_sb(pr, mag, struct hfs_mdb);
 154         if (!hfs)
 155                 return -1;
 156
 157         if ((memcmp(hfs->embed_sig, "H+", 2) == 0) ||
 158             (memcmp(hfs->embed_sig, "HX", 2) == 0))
 159                 return 1;       /* Not hfs, but an embedded HFS+ */
 160
 161         hfs_set_uuid(pr, hfs->finder_info.id, sizeof(hfs->finder_info.id));
 162
 163         blkid_probe_set_label(pr, hfs->label, hfs->label_len);
 164         return 0;
 165 }
 166
 167 static int probe_hfsplus(blkid_probe pr, const struct blkid_idmag *mag)
 168 {
 169         struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
 170         struct hfsplus_bnode_descriptor *descr;
 171         struct hfsplus_bheader_record *bnode;
 172         struct hfsplus_catalog_key *key;
 173         struct hfsplus_vol_header *hfsplus;
 174         struct hfs_mdb *sbd;
 175         unsigned int alloc_block_size;
 176         unsigned int alloc_first_block;
 177         unsigned int embed_first_block;
 178         unsigned int off = 0;
 179         unsigned int blocksize;
 180         unsigned int cat_block;
 181         unsigned int ext_block_start;
 182         unsigned int ext_block_count;
 183         unsigned int record_count;
 184         unsigned int leaf_node_head;
 185         unsigned int leaf_node_count;
 186         unsigned int leaf_node_size;
 187         unsigned int leaf_block;
 188         int ext;
 189         uint64_t leaf_off;
 190         unsigned char *buf;
 191
 192         sbd = blkid_probe_get_sb(pr, mag, struct hfs_mdb);
 193         if (!sbd)
 194                 return -1;
 195
 196         /* Check for a HFS+ volume embedded in a HFS volume */
 197         if (memcmp(sbd->signature, "BD", 2) == 0) {
 198                 if ((memcmp(sbd->embed_sig, "H+", 2) != 0) &&
 199                     (memcmp(sbd->embed_sig, "HX", 2) != 0))
 200                         /* This must be an HFS volume, so fail */
 201                         return 1;
 202
 203                 alloc_block_size = be32_to_cpu(sbd->al_blk_size);
 204                 alloc_first_block = be16_to_cpu(sbd->al_bl_st);
 205                 embed_first_block = be16_to_cpu(sbd->embed_startblock);
 206                 off = (alloc_first_block * 512) +
 207                         (embed_first_block * alloc_block_size);
 208
 209                 buf = blkid_probe_get_buffer(pr,
 210                                 off + (mag->kboff * 1024),
 211                                 sizeof(struct hfsplus_vol_header));
 212                 hfsplus = (struct hfsplus_vol_header *) buf;
 213
 214         } else
 215                 hfsplus = blkid_probe_get_sb(pr, mag,
 216                                 struct hfsplus_vol_header);
 217
 218         if (!hfsplus)
 219                 return -1;
 220
 221         if ((memcmp(hfsplus->signature, "H+", 2) != 0) &&
 222             (memcmp(hfsplus->signature, "HX", 2) != 0))
 223                 return 1;
 224
 225         hfs_set_uuid(pr, hfsplus->finder_info.id, sizeof(hfsplus->finder_info.id));
 226
 227         blocksize = be32_to_cpu(hfsplus->blocksize);
 228         memcpy(extents, hfsplus->cat_file.extents, sizeof(extents));
 229         cat_block = be32_to_cpu(extents[0].start_block);
 230
 231         buf = blkid_probe_get_buffer(pr,
 232                         off + (cat_block * blocksize), 0x2000);
 233         if (!buf)
 234                 return 0;
 235
 236         bnode = (struct hfsplus_bheader_record *)
 237                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 238
 239         leaf_node_head = be32_to_cpu(bnode->leaf_head);
 240         leaf_node_size = be16_to_cpu(bnode->node_size);
 241         leaf_node_count = be32_to_cpu(bnode->leaf_count);
 242         if (leaf_node_count == 0)
 243                 return 0;
 244
 245         leaf_block = (leaf_node_head * leaf_node_size) / blocksize;
 246
 247         /* get physical location */
 248         for (ext = 0; ext < HFSPLUS_EXTENT_COUNT; ext++) {
 249                 ext_block_start = be32_to_cpu(extents[ext].start_block);
 250                 ext_block_count = be32_to_cpu(extents[ext].block_count);
 251                 if (ext_block_count == 0)
 252                         return 0;
 253
 254                 /* this is our extent */
 255                 if (leaf_block < ext_block_count)
 256                         break;
 257
 258                 leaf_block -= ext_block_count;
 259         }
 260         if (ext == HFSPLUS_EXTENT_COUNT)
 261                 return 0;
 262
 263         leaf_off = (ext_block_start + leaf_block) * blocksize;
 264
 265         buf = blkid_probe_get_buffer(pr, off + leaf_off, leaf_node_size);
 266         if (!buf)
 267                 return 0;
 268
 269         descr = (struct hfsplus_bnode_descriptor *) buf;
 270         record_count = be16_to_cpu(descr->num_recs);
 271         if (record_count == 0)
 272                 return 0;
 273
 274         if (descr->type != HFS_NODE_LEAF)
 275                 return 0;
 276
 277         key = (struct hfsplus_catalog_key *)
 278                 &buf[sizeof(struct hfsplus_bnode_descriptor)];
 279
 280         if (be32_to_cpu(key->parent_id) != HFSPLUS_POR_CNID)
 281                 return 0;
 282
 283         blkid_probe_set_utf8label(pr, key->unicode,
 284                         be16_to_cpu(key->unicode_len) * 2,
 285                         BLKID_ENC_UTF16BE);
 286         return 0;
 287 }
 288
 289 const struct blkid_idinfo hfs_idinfo =
 290 {
 291         .name           = "hfs",
 292         .usage          = BLKID_USAGE_FILESYSTEM,
 293         .probefunc      = probe_hfs,
 294         .magics         =
 295         {
 296                 { .magic = "BD", .len = 2, .kboff = 1 },
 297                 { NULL }
 298         }
 299 };
 300
 301 const struct blkid_idinfo hfsplus_idinfo =
 302 {
 303         .name           = "hfsplus",
 304         .usage          = BLKID_USAGE_FILESYSTEM,
 305         .probefunc      = probe_hfsplus,
 306         .magics         =
 307         {
 308                 { .magic = "BD", .len = 2, .kboff = 1 },
 309                 { .magic = "H+", .len = 2, .kboff = 1 },
 310                 { .magic = "HX", .len = 2, .kboff = 1 },
 311                 { NULL }
 312         }
 313 };