bsd/hfs/hfs_format.h

   1 /*
   2  * Copyright (c) 2000-2009 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 #ifndef __HFS_FORMAT__
  29 #define __HFS_FORMAT__
  30
  31 #include <sys/types.h>
  32 #include <sys/appleapiopts.h>
  33
  34 /*
  35  * hfs_format.c
  36  *
  37  * This file describes the on-disk format for HFS and HFS Plus volumes.
  38  * The HFS Plus volume format is desciibed in detail in Apple Technote 1150.
  39  *
  40  * http://developer.apple.com/technotes/tn/tn1150.html
  41  *
  42  */
  43
  44 #ifdef __cplusplus
  45 extern "C" {
  46 #endif
  47
  48 /* some on-disk hfs structures have 68K alignment (misaligned) */
  49
  50 /* Signatures used to differentiate between HFS and HFS Plus volumes */
  51 enum {
  52         kHFSSigWord             = 0x4244,       /* 'BD' in ASCII */
  53         kHFSPlusSigWord         = 0x482B,       /* 'H+' in ASCII */
  54         kHFSXSigWord            = 0x4858,       /* 'HX' in ASCII */
  55
  56         kHFSPlusVersion         = 0x0004,       /* 'H+' volumes are version 4 only */
  57         kHFSXVersion            = 0x0005,       /* 'HX' volumes start with version 5 */
  58
  59         kHFSPlusMountVersion    = 0x31302E30,   /* '10.0' for Mac OS X */
  60         kHFSJMountVersion       = 0x4846534a,   /* 'HFSJ' for journaled HFS+ on OS X */
  61         kFSKMountVersion        = 0x46534b21    /* 'FSK!' for failed journal replay */
  62 };
  63
  64
  65 #ifdef __APPLE_API_PRIVATE
  66 /*
  67  * Mac OS X has two special directories on HFS+ volumes for hardlinked files
  68  * and hardlinked directories as well as for open-unlinked files.
  69  *
  70  * These directories and their contents are not exported from the filesystem
  71  * under Mac OS X.
  72  */
  73 #define HFSPLUSMETADATAFOLDER       "\xE2\x90\x80\xE2\x90\x80\xE2\x90\x80\xE2\x90\x80HFS+ Private Data"
  74 #define HFSPLUS_DIR_METADATA_FOLDER ".HFS+ Private Directory Data\xd"
  75
  76 /*
  77  * Files in the "HFS+ Private Data" folder have one of the following prefixes
  78  * followed by a decimal number (no leading zeros) for the file ID.
  79  *
  80  * Note: Earlier version of Mac OS X used a 32 bit random number for the link
  81  * ref number instead of the file id.
  82  *
  83  * e.g.  iNode7182000 and temp3296
  84  */
  85 #define HFS_INODE_PREFIX        "iNode"
  86 #define HFS_DELETE_PREFIX       "temp"
  87
  88 /*
  89  * Files in the ".HFS+ Private Directory Data" folder have the following
  90  * prefix followed by a decimal number (no leading zeros) for the file ID.
  91  *
  92  * e.g. dir_555
  93  */
  94 #define HFS_DIRINODE_PREFIX     "dir_"
  95
  96 /*
  97  * Hardlink inodes save the head of the link chain in
  98  * an extended attribute named FIRST_LINK_XATTR_NAME.
  99  * The attribute data is the decimal value in ASCII
 100  * of the cnid for the first link in the chain.
 101  *
 102  * This extended attribute is private (i.e. its not
 103  * exported in the getxattr/listxattr POSIX APIs).
 104  */
 105 #define FIRST_LINK_XATTR_NAME   "com.apple.system.hfs.firstlink"
 106 #define FIRST_LINK_XATTR_REC_SIZE (sizeof(HFSPlusAttrData) - 2 + 12)
 107
 108 /*
 109  * The name space ID for generating an HFS volume UUID
 110  *
 111  * B3E20F39-F292-11D6-97A4-00306543ECAC
 112  */
 113 #define HFS_UUID_NAMESPACE_ID  "\xB3\xE2\x0F\x39\xF2\x92\x11\xD6\x97\xA4\x00\x30\x65\x43\xEC\xAC"
 114
 115 #endif /* __APPLE_API_PRIVATE */
 116
 117 /*
 118  * Indirect link files (hard links) have the following type/creator.
 119  */
 120 enum {
 121         kHardLinkFileType = 0x686C6E6B,  /* 'hlnk' */
 122         kHFSPlusCreator   = 0x6866732B   /* 'hfs+' */
 123 };
 124
 125
 126 /*
 127  *      File type and creator for symbolic links
 128  */
 129 enum {
 130       kSymLinkFileType  = 0x736C6E6B, /* 'slnk' */
 131       kSymLinkCreator   = 0x72686170  /* 'rhap' */
 132 };
 133
 134
 135 #ifndef _HFSUNISTR255_DEFINED_
 136 #define _HFSUNISTR255_DEFINED_
 137 /* Unicode strings are used for HFS Plus file and folder names */
 138 struct HFSUniStr255 {
 139         u_int16_t       length;         /* number of unicode characters */
 140         u_int16_t       unicode[255];   /* unicode characters */
 141 } __attribute__((aligned(2), packed));
 142 typedef struct HFSUniStr255 HFSUniStr255;
 143 typedef const HFSUniStr255 *ConstHFSUniStr255Param;
 144 #endif /* _HFSUNISTR255_DEFINED_ */
 145
 146 enum {
 147         kHFSMaxVolumeNameChars          = 27,
 148         kHFSMaxFileNameChars            = 31,
 149         kHFSPlusMaxFileNameChars        = 255
 150 };
 151
 152
 153 /* Extent overflow file data structures */
 154
 155 /* HFS Extent key */
 156 struct HFSExtentKey {
 157         u_int8_t        keyLength;      /* length of key, excluding this field */
 158         u_int8_t        forkType;       /* 0 = data fork, FF = resource fork */
 159         u_int32_t       fileID;         /* file ID */
 160         u_int16_t       startBlock;     /* first file allocation block number in this extent */
 161 } __attribute__((aligned(2), packed));
 162 typedef struct HFSExtentKey HFSExtentKey;
 163
 164 /* HFS Plus Extent key */
 165 struct HFSPlusExtentKey {
 166         u_int16_t       keyLength;              /* length of key, excluding this field */
 167         u_int8_t        forkType;               /* 0 = data fork, FF = resource fork */
 168         u_int8_t        pad;                    /* make the other fields align on 32-bit boundary */
 169         u_int32_t       fileID;                 /* file ID */
 170         u_int32_t       startBlock;             /* first file allocation block number in this extent */
 171 } __attribute__((aligned(2), packed));
 172 typedef struct HFSPlusExtentKey HFSPlusExtentKey;
 173
 174 /* Number of extent descriptors per extent record */
 175 enum {
 176         kHFSExtentDensity       = 3,
 177         kHFSPlusExtentDensity   = 8
 178 };
 179
 180 /* HFS extent descriptor */
 181 struct HFSExtentDescriptor {
 182         u_int16_t       startBlock;             /* first allocation block */
 183         u_int16_t       blockCount;             /* number of allocation blocks */
 184 } __attribute__((aligned(2), packed));
 185 typedef struct HFSExtentDescriptor HFSExtentDescriptor;
 186
 187 /* HFS Plus extent descriptor */
 188 struct HFSPlusExtentDescriptor {
 189         u_int32_t       startBlock;             /* first allocation block */
 190         u_int32_t       blockCount;             /* number of allocation blocks */
 191 } __attribute__((aligned(2), packed));
 192 typedef struct HFSPlusExtentDescriptor HFSPlusExtentDescriptor;
 193
 194 /* HFS extent record */
 195 typedef HFSExtentDescriptor HFSExtentRecord[3];
 196
 197 /* HFS Plus extent record */
 198 typedef HFSPlusExtentDescriptor HFSPlusExtentRecord[8];
 199
 200
 201 /* Finder information */
 202 struct FndrFileInfo {
 203         u_int32_t       fdType;         /* file type */
 204         u_int32_t       fdCreator;      /* file creator */
 205         u_int16_t       fdFlags;        /* Finder flags */
 206         struct {
 207             int16_t     v;              /* file's location */
 208             int16_t     h;
 209         } fdLocation;
 210         int16_t         opaque;
 211 } __attribute__((aligned(2), packed));
 212 typedef struct FndrFileInfo FndrFileInfo;
 213
 214 struct FndrDirInfo {
 215         struct {                        /* folder's window rectangle */
 216             int16_t     top;
 217             int16_t     left;
 218             int16_t     bottom;
 219             int16_t     right;
 220         } frRect;
 221         unsigned short  frFlags;        /* Finder flags */
 222         struct {
 223             u_int16_t   v;              /* folder's location */
 224             u_int16_t   h;
 225         } frLocation;
 226         int16_t         opaque;
 227 } __attribute__((aligned(2), packed));
 228 typedef struct FndrDirInfo FndrDirInfo;
 229
 230 struct FndrOpaqueInfo {
 231         int8_t opaque[16];
 232 } __attribute__((aligned(2), packed));
 233 typedef struct FndrOpaqueInfo FndrOpaqueInfo;
 234
 235 struct FndrExtendedDirInfo {
 236         u_int32_t point;
 237         u_int32_t date_added;
 238         u_int16_t extended_flags;
 239         u_int16_t reserved3;
 240         u_int32_t reserved4;
 241 } __attribute__((aligned(2), packed));
 242
 243 struct FndrExtendedFileInfo {
 244         u_int32_t reserved1;
 245         u_int32_t date_added;
 246         u_int16_t extended_flags;
 247         u_int16_t reserved2;
 248         u_int32_t reserved3;
 249 } __attribute__((aligned(2), packed));
 250
 251 /* HFS Plus Fork data info - 80 bytes */
 252 struct HFSPlusForkData {
 253         u_int64_t               logicalSize;    /* fork's logical size in bytes */
 254         u_int32_t               clumpSize;      /* fork's clump size in bytes */
 255         u_int32_t               totalBlocks;    /* total blocks used by this fork */
 256         HFSPlusExtentRecord     extents;        /* initial set of extents */
 257 } __attribute__((aligned(2), packed));
 258 typedef struct HFSPlusForkData HFSPlusForkData;
 259
 260
 261 /* Mac OS X has 16 bytes worth of "BSD" info.
 262  *
 263  * Note:  Mac OS 9 implementations and applications
 264  * should preserve, but not change, this information.
 265  */
 266 struct HFSPlusBSDInfo {
 267         u_int32_t       ownerID;        /* user-id of owner or hard link chain previous link */
 268         u_int32_t       groupID;        /* group-id of owner or hard link chain next link */
 269         u_int8_t        adminFlags;     /* super-user changeable flags */
 270         u_int8_t        ownerFlags;     /* owner changeable flags */
 271         u_int16_t       fileMode;       /* file type and permission bits */
 272         union {
 273             u_int32_t   iNodeNum;       /* indirect node number (hard links only) */
 274             u_int32_t   linkCount;      /* links that refer to this indirect node */
 275             u_int32_t   rawDevice;      /* special file device (FBLK and FCHR only) */
 276         } special;
 277 } __attribute__((aligned(2), packed));
 278 typedef struct HFSPlusBSDInfo HFSPlusBSDInfo;
 279
 280 /*
 281  * Hardlink "links" resolve to an inode
 282  * and the actual uid/gid comes from that
 283  * inode.
 284  *
 285  * We repurpose the links's uid/gid fields
 286  * for the hardlink link chain. The chain
 287  * consists of a doubly linked list of file
 288  * ids.
 289  */
 290
 291 #define hl_firstLinkID     reserved1         /* Valid only if HasLinkChain flag is set (indirect nodes only) */
 292
 293 #define hl_prevLinkID      bsdInfo.ownerID   /* Valid only if HasLinkChain flag is set */
 294 #define hl_nextLinkID      bsdInfo.groupID   /* Valid only if HasLinkChain flag is set */
 295
 296 #define hl_linkReference   bsdInfo.special.iNodeNum
 297 #define hl_linkCount       bsdInfo.special.linkCount
 298
 299
 300 /* Catalog file data structures */
 301
 302 enum {
 303         kHFSRootParentID                = 1,    /* Parent ID of the root folder */
 304         kHFSRootFolderID                = 2,    /* Folder ID of the root folder */
 305         kHFSExtentsFileID               = 3,    /* File ID of the extents file */
 306         kHFSCatalogFileID               = 4,    /* File ID of the catalog file */
 307         kHFSBadBlockFileID              = 5,    /* File ID of the bad allocation block file */
 308         kHFSAllocationFileID            = 6,    /* File ID of the allocation file (HFS Plus only) */
 309         kHFSStartupFileID               = 7,    /* File ID of the startup file (HFS Plus only) */
 310         kHFSAttributesFileID            = 8,    /* File ID of the attribute file (HFS Plus only) */
 311         kHFSAttributeDataFileID         = 13,   /* Used in Mac OS X runtime for extent based attributes */
 312                                                 /* kHFSAttributeDataFileID is never stored on disk. */
 313         kHFSRepairCatalogFileID         = 14,   /* Used when rebuilding Catalog B-tree */
 314         kHFSBogusExtentFileID           = 15,   /* Used for exchanging extents in extents file */
 315         kHFSFirstUserCatalogNodeID      = 16
 316 };
 317
 318 /* HFS catalog key */
 319 struct HFSCatalogKey {
 320         u_int8_t        keyLength;              /* key length (in bytes) */
 321         u_int8_t        reserved;               /* reserved (set to zero) */
 322         u_int32_t       parentID;               /* parent folder ID */
 323         u_int8_t        nodeName[kHFSMaxFileNameChars + 1]; /* catalog node name */
 324 } __attribute__((aligned(2), packed));
 325 typedef struct HFSCatalogKey HFSCatalogKey;
 326
 327 /* HFS Plus catalog key */
 328 struct HFSPlusCatalogKey {
 329         u_int16_t               keyLength;      /* key length (in bytes) */
 330         u_int32_t               parentID;       /* parent folder ID */
 331         HFSUniStr255            nodeName;       /* catalog node name */
 332 } __attribute__((aligned(2), packed));
 333 typedef struct HFSPlusCatalogKey HFSPlusCatalogKey;
 334
 335 /* Catalog record types */
 336 enum {
 337         /* HFS Catalog Records */
 338         kHFSFolderRecord                = 0x0100,       /* Folder record */
 339         kHFSFileRecord                  = 0x0200,       /* File record */
 340         kHFSFolderThreadRecord          = 0x0300,       /* Folder thread record */
 341         kHFSFileThreadRecord            = 0x0400,       /* File thread record */
 342
 343         /* HFS Plus Catalog Records */
 344         kHFSPlusFolderRecord            = 1,            /* Folder record */
 345         kHFSPlusFileRecord              = 2,            /* File record */
 346         kHFSPlusFolderThreadRecord      = 3,            /* Folder thread record */
 347         kHFSPlusFileThreadRecord        = 4             /* File thread record */
 348 };
 349
 350
 351 /* Catalog file record flags */
 352 enum {
 353         kHFSFileLockedBit       = 0x0000,       /* file is locked and cannot be written to */
 354         kHFSFileLockedMask      = 0x0001,
 355
 356         kHFSThreadExistsBit     = 0x0001,       /* a file thread record exists for this file */
 357         kHFSThreadExistsMask    = 0x0002,
 358
 359         kHFSHasAttributesBit    = 0x0002,       /* object has extended attributes */
 360         kHFSHasAttributesMask   = 0x0004,
 361
 362         kHFSHasSecurityBit      = 0x0003,       /* object has security data (ACLs) */
 363         kHFSHasSecurityMask     = 0x0008,
 364
 365         kHFSHasFolderCountBit   = 0x0004,       /* only for HFSX, folder maintains a separate sub-folder count */
 366         kHFSHasFolderCountMask  = 0x0010,       /* (sum of folder records and directory hard links) */
 367
 368         kHFSHasLinkChainBit     = 0x0005,       /* has hardlink chain (inode or link) */
 369         kHFSHasLinkChainMask    = 0x0020,
 370
 371         kHFSHasChildLinkBit     = 0x0006,       /* folder has a child that's a dir link */
 372         kHFSHasChildLinkMask    = 0x0040,
 373
 374         kHFSHasDateAddedBit = 0x0007,   /* File/Folder has the date-added stored in the finder info. */
 375         kHFSHasDateAddedMask = 0x0080
 376
 377 };
 378
 379
 380 /* HFS catalog folder record - 70 bytes */
 381 struct HFSCatalogFolder {
 382         int16_t                 recordType;             /* == kHFSFolderRecord */
 383         u_int16_t               flags;                  /* folder flags */
 384         u_int16_t               valence;                /* folder valence */
 385         u_int32_t               folderID;               /* folder ID */
 386         u_int32_t               createDate;             /* date and time of creation */
 387         u_int32_t               modifyDate;             /* date and time of last modification */
 388         u_int32_t               backupDate;             /* date and time of last backup */
 389         FndrDirInfo             userInfo;               /* Finder information */
 390         FndrOpaqueInfo          finderInfo;             /* additional Finder information */
 391         u_int32_t               reserved[4];            /* reserved - initialized as zero */
 392 } __attribute__((aligned(2), packed));
 393 typedef struct HFSCatalogFolder HFSCatalogFolder;
 394
 395 /* HFS Plus catalog folder record - 88 bytes */
 396 struct HFSPlusCatalogFolder {
 397         int16_t                 recordType;             /* == kHFSPlusFolderRecord */
 398         u_int16_t               flags;                  /* file flags */
 399         u_int32_t               valence;                /* folder's item count */
 400         u_int32_t               folderID;               /* folder ID */
 401         u_int32_t               createDate;             /* date and time of creation */
 402         u_int32_t               contentModDate;         /* date and time of last content modification */
 403         u_int32_t               attributeModDate;       /* date and time of last attribute modification */
 404         u_int32_t               accessDate;             /* date and time of last access (MacOS X only) */
 405         u_int32_t               backupDate;             /* date and time of last backup */
 406         HFSPlusBSDInfo          bsdInfo;                /* permissions (for MacOS X) */
 407         FndrDirInfo             userInfo;               /* Finder information */
 408         FndrOpaqueInfo          finderInfo;             /* additional Finder information */
 409         u_int32_t               textEncoding;           /* hint for name conversions */
 410         u_int32_t               folderCount;            /* number of enclosed folders, active when HasFolderCount is set */
 411 } __attribute__((aligned(2), packed));
 412 typedef struct HFSPlusCatalogFolder HFSPlusCatalogFolder;
 413
 414 /* HFS catalog file record - 102 bytes */
 415 struct HFSCatalogFile {
 416         int16_t                 recordType;             /* == kHFSFileRecord */
 417         u_int8_t                flags;                  /* file flags */
 418         int8_t                  fileType;               /* file type (unused ?) */
 419         FndrFileInfo            userInfo;               /* Finder information */
 420         u_int32_t               fileID;                 /* file ID */
 421         u_int16_t               dataStartBlock;         /* not used - set to zero */
 422         int32_t                 dataLogicalSize;        /* logical EOF of data fork */
 423         int32_t                 dataPhysicalSize;       /* physical EOF of data fork */
 424         u_int16_t               rsrcStartBlock;         /* not used - set to zero */
 425         int32_t                 rsrcLogicalSize;        /* logical EOF of resource fork */
 426         int32_t                 rsrcPhysicalSize;       /* physical EOF of resource fork */
 427         u_int32_t               createDate;             /* date and time of creation */
 428         u_int32_t               modifyDate;             /* date and time of last modification */
 429         u_int32_t               backupDate;             /* date and time of last backup */
 430         FndrOpaqueInfo          finderInfo;             /* additional Finder information */
 431         u_int16_t               clumpSize;              /* file clump size (not used) */
 432         HFSExtentRecord         dataExtents;            /* first data fork extent record */
 433         HFSExtentRecord         rsrcExtents;            /* first resource fork extent record */
 434         u_int32_t               reserved;               /* reserved - initialized as zero */
 435 } __attribute__((aligned(2), packed));
 436 typedef struct HFSCatalogFile HFSCatalogFile;
 437
 438 /* HFS Plus catalog file record - 248 bytes */
 439 struct HFSPlusCatalogFile {
 440         int16_t                 recordType;             /* == kHFSPlusFileRecord */
 441         u_int16_t               flags;                  /* file flags */
 442         u_int32_t               reserved1;              /* reserved - initialized as zero */
 443         u_int32_t               fileID;                 /* file ID */
 444         u_int32_t               createDate;             /* date and time of creation */
 445         u_int32_t               contentModDate;         /* date and time of last content modification */
 446         u_int32_t               attributeModDate;       /* date and time of last attribute modification */
 447         u_int32_t               accessDate;             /* date and time of last access (MacOS X only) */
 448         u_int32_t               backupDate;             /* date and time of last backup */
 449         HFSPlusBSDInfo          bsdInfo;                /* permissions (for MacOS X) */
 450         FndrFileInfo            userInfo;               /* Finder information */
 451         FndrOpaqueInfo          finderInfo;             /* additional Finder information */
 452         u_int32_t               textEncoding;           /* hint for name conversions */
 453         u_int32_t               reserved2;              /* reserved - initialized as zero */
 454
 455         /* Note: these start on double long (64 bit) boundary */
 456         HFSPlusForkData         dataFork;               /* size and block data for data fork */
 457         HFSPlusForkData         resourceFork;           /* size and block data for resource fork */
 458 } __attribute__((aligned(2), packed));
 459 typedef struct HFSPlusCatalogFile HFSPlusCatalogFile;
 460
 461 /* HFS catalog thread record - 46 bytes */
 462 struct HFSCatalogThread {
 463         int16_t         recordType;             /* == kHFSFolderThreadRecord or kHFSFileThreadRecord */
 464         int32_t         reserved[2];            /* reserved - initialized as zero */
 465         u_int32_t       parentID;               /* parent ID for this catalog node */
 466         u_int8_t        nodeName[kHFSMaxFileNameChars + 1]; /* name of this catalog node */
 467 } __attribute__((aligned(2), packed));
 468 typedef struct HFSCatalogThread HFSCatalogThread;
 469
 470 /* HFS Plus catalog thread record -- 264 bytes */
 471 struct HFSPlusCatalogThread {
 472         int16_t         recordType;             /* == kHFSPlusFolderThreadRecord or kHFSPlusFileThreadRecord */
 473         int16_t         reserved;               /* reserved - initialized as zero */
 474         u_int32_t       parentID;               /* parent ID for this catalog node */
 475         HFSUniStr255    nodeName;               /* name of this catalog node (variable length) */
 476 } __attribute__((aligned(2), packed));
 477 typedef struct HFSPlusCatalogThread HFSPlusCatalogThread;
 478
 479 #ifdef __APPLE_API_UNSTABLE
 480 /*
 481         These are the types of records in the attribute B-tree.  The values were
 482         chosen so that they wouldn't conflict with the catalog record types.
 483 */
 484 enum {
 485         kHFSPlusAttrInlineData  = 0x10,   /* attributes whose data fits in a b-tree node */
 486         kHFSPlusAttrForkData    = 0x20,   /* extent based attributes (data lives in extents) */
 487         kHFSPlusAttrExtents     = 0x30    /* overflow extents for large attributes */
 488 };
 489
 490
 491 /*
 492         HFSPlusAttrForkData
 493         For larger attributes, whose value is stored in allocation blocks.
 494         If the attribute has more than 8 extents, there will be additional
 495         records (of type HFSPlusAttrExtents) for this attribute.
 496 */
 497 struct HFSPlusAttrForkData {
 498         u_int32_t       recordType;             /* == kHFSPlusAttrForkData*/
 499         u_int32_t       reserved;
 500         HFSPlusForkData theFork;                /* size and first extents of value*/
 501 } __attribute__((aligned(2), packed));
 502 typedef struct HFSPlusAttrForkData HFSPlusAttrForkData;
 503
 504 /*
 505         HFSPlusAttrExtents
 506         This record contains information about overflow extents for large,
 507         fragmented attributes.
 508 */
 509 struct HFSPlusAttrExtents {
 510         u_int32_t               recordType;     /* == kHFSPlusAttrExtents*/
 511         u_int32_t               reserved;
 512         HFSPlusExtentRecord     extents;        /* additional extents*/
 513 } __attribute__((aligned(2), packed));
 514 typedef struct HFSPlusAttrExtents HFSPlusAttrExtents;
 515
 516 /*
 517  * Atrributes B-tree Data Record
 518  *
 519  * For small attributes, whose entire value is stored
 520  * within a single B-tree record.
 521  */
 522 struct HFSPlusAttrData {
 523         u_int32_t    recordType;   /* == kHFSPlusAttrInlineData */
 524         u_int32_t    reserved[2];
 525         u_int32_t    attrSize;     /* size of attribute data in bytes */
 526         u_int8_t     attrData[2];  /* variable length */
 527 } __attribute__((aligned(2), packed));
 528 typedef struct HFSPlusAttrData HFSPlusAttrData;
 529
 530
 531 /* HFSPlusAttrInlineData is obsolete use HFSPlusAttrData instead */
 532 struct HFSPlusAttrInlineData {
 533         u_int32_t       recordType;
 534         u_int32_t       reserved;
 535         u_int32_t       logicalSize;
 536         u_int8_t        userData[2];
 537 } __attribute__((aligned(2), packed));
 538 typedef struct HFSPlusAttrInlineData HFSPlusAttrInlineData;
 539
 540
 541 /*      A generic Attribute Record*/
 542 union HFSPlusAttrRecord {
 543         u_int32_t               recordType;
 544         HFSPlusAttrInlineData   inlineData;   /* NOT USED */
 545         HFSPlusAttrData         attrData;
 546         HFSPlusAttrForkData     forkData;
 547         HFSPlusAttrExtents      overflowExtents;
 548 };
 549 typedef union HFSPlusAttrRecord HFSPlusAttrRecord;
 550
 551 /* Attribute key */
 552 enum { kHFSMaxAttrNameLen = 127 };
 553 struct HFSPlusAttrKey {
 554         u_int16_t     keyLength;       /* key length (in bytes) */
 555         u_int16_t     pad;             /* set to zero */
 556         u_int32_t     fileID;          /* file associated with attribute */
 557         u_int32_t     startBlock;      /* first allocation block number for extents */
 558         u_int16_t     attrNameLen;     /* number of unicode characters */
 559         u_int16_t     attrName[kHFSMaxAttrNameLen];   /* attribute name (Unicode) */
 560 } __attribute__((aligned(2), packed));
 561 typedef struct HFSPlusAttrKey HFSPlusAttrKey;
 562
 563 #define kHFSPlusAttrKeyMaximumLength   (sizeof(HFSPlusAttrKey) - sizeof(u_int16_t))
 564 #define kHFSPlusAttrKeyMinimumLength   (kHFSPlusAttrKeyMaximumLength - kHFSMaxAttrNameLen*sizeof(u_int16_t))
 565
 566 #endif /* __APPLE_API_UNSTABLE */
 567
 568
 569 /* Key and node lengths */
 570 enum {
 571         kHFSPlusExtentKeyMaximumLength = sizeof(HFSPlusExtentKey) - sizeof(u_int16_t),
 572         kHFSExtentKeyMaximumLength      = sizeof(HFSExtentKey) - sizeof(u_int8_t),
 573         kHFSPlusCatalogKeyMaximumLength = sizeof(HFSPlusCatalogKey) - sizeof(u_int16_t),
 574         kHFSPlusCatalogKeyMinimumLength = kHFSPlusCatalogKeyMaximumLength - sizeof(HFSUniStr255) + sizeof(u_int16_t),
 575         kHFSCatalogKeyMaximumLength     = sizeof(HFSCatalogKey) - sizeof(u_int8_t),
 576         kHFSCatalogKeyMinimumLength     = kHFSCatalogKeyMaximumLength - (kHFSMaxFileNameChars + 1) + sizeof(u_int8_t),
 577         kHFSPlusCatalogMinNodeSize      = 4096,
 578         kHFSPlusExtentMinNodeSize       = 512,
 579         kHFSPlusAttrMinNodeSize         = 4096
 580 };
 581
 582 /* HFS and HFS Plus volume attribute bits */
 583 enum {
 584         /* Bits 0-6 are reserved (always cleared by MountVol call) */
 585         kHFSVolumeHardwareLockBit       = 7,            /* volume is locked by hardware */
 586         kHFSVolumeUnmountedBit          = 8,            /* volume was successfully unmounted */
 587         kHFSVolumeSparedBlocksBit       = 9,            /* volume has bad blocks spared */
 588         kHFSVolumeNoCacheRequiredBit = 10,              /* don't cache volume blocks (i.e. RAM or ROM disk) */
 589         kHFSBootVolumeInconsistentBit = 11,             /* boot volume is inconsistent (System 7.6 and later) */
 590         kHFSCatalogNodeIDsReusedBit = 12,
 591         kHFSVolumeJournaledBit = 13,                    /* this volume has a journal on it */
 592         kHFSVolumeInconsistentBit = 14,                 /* serious inconsistencies detected at runtime */
 593         kHFSVolumeSoftwareLockBit       = 15,           /* volume is locked by software */
 594         /*
 595          * HFS only has 16 bits of attributes in the MDB, but HFS Plus has 32 bits.
 596          * Therefore, bits 16-31 can only be used on HFS Plus.
 597          */
 598         kHFSUnusedNodeFixBit = 31,                              /* Unused nodes in the Catalog B-tree have been zero-filled.  See Radar #6947811. */
 599         kHFSContentProtectionBit = 30,                  /* Volume has per-file content protection */
 600
 601         kHFSVolumeHardwareLockMask      = 1 << kHFSVolumeHardwareLockBit,
 602         kHFSVolumeUnmountedMask         = 1 << kHFSVolumeUnmountedBit,
 603         kHFSVolumeSparedBlocksMask      = 1 << kHFSVolumeSparedBlocksBit,
 604         kHFSVolumeNoCacheRequiredMask = 1 << kHFSVolumeNoCacheRequiredBit,
 605         kHFSBootVolumeInconsistentMask = 1 << kHFSBootVolumeInconsistentBit,
 606         kHFSCatalogNodeIDsReusedMask = 1 << kHFSCatalogNodeIDsReusedBit,
 607         kHFSVolumeJournaledMask = 1 << kHFSVolumeJournaledBit,
 608         kHFSVolumeInconsistentMask = 1 << kHFSVolumeInconsistentBit,
 609         kHFSVolumeSoftwareLockMask      = 1 << kHFSVolumeSoftwareLockBit,
 610         kHFSUnusedNodeFixMask = 1 << kHFSUnusedNodeFixBit,
 611         kHFSContentProtectionMask = 1 << kHFSContentProtectionBit,
 612         kHFSMDBAttributesMask           = 0x8380
 613 };
 614
 615 enum {
 616         kHFSUnusedNodesFixDate = 0xc5ef2480             /* March 25, 2009 */
 617 };
 618
 619 /* HFS Master Directory Block - 162 bytes */
 620 /* Stored at sector #2 (3rd sector) and second-to-last sector. */
 621 struct HFSMasterDirectoryBlock {
 622         u_int16_t               drSigWord;      /* == kHFSSigWord */
 623         u_int32_t               drCrDate;       /* date and time of volume creation */
 624         u_int32_t               drLsMod;        /* date and time of last modification */
 625         u_int16_t               drAtrb;         /* volume attributes */
 626         u_int16_t               drNmFls;        /* number of files in root folder */
 627         u_int16_t               drVBMSt;        /* first block of volume bitmap */
 628         u_int16_t               drAllocPtr;     /* start of next allocation search */
 629         u_int16_t               drNmAlBlks;     /* number of allocation blocks in volume */
 630         u_int32_t               drAlBlkSiz;     /* size (in bytes) of allocation blocks */
 631         u_int32_t               drClpSiz;       /* default clump size */
 632         u_int16_t               drAlBlSt;       /* first allocation block in volume */
 633         u_int32_t               drNxtCNID;      /* next unused catalog node ID */
 634         u_int16_t               drFreeBks;      /* number of unused allocation blocks */
 635         u_int8_t                drVN[kHFSMaxVolumeNameChars + 1];  /* volume name */
 636         u_int32_t               drVolBkUp;      /* date and time of last backup */
 637         u_int16_t               drVSeqNum;      /* volume backup sequence number */
 638         u_int32_t               drWrCnt;        /* volume write count */
 639         u_int32_t               drXTClpSiz;     /* clump size for extents overflow file */
 640         u_int32_t               drCTClpSiz;     /* clump size for catalog file */
 641         u_int16_t               drNmRtDirs;     /* number of directories in root folder */
 642         u_int32_t               drFilCnt;       /* number of files in volume */
 643         u_int32_t               drDirCnt;       /* number of directories in volume */
 644         u_int32_t               drFndrInfo[8];  /* information used by the Finder */
 645         u_int16_t               drEmbedSigWord; /* embedded volume signature (formerly drVCSize) */
 646         HFSExtentDescriptor     drEmbedExtent;  /* embedded volume location and size (formerly drVBMCSize and drCtlCSize) */
 647         u_int32_t               drXTFlSize;     /* size of extents overflow file */
 648         HFSExtentRecord         drXTExtRec;     /* extent record for extents overflow file */
 649         u_int32_t               drCTFlSize;     /* size of catalog file */
 650         HFSExtentRecord         drCTExtRec;     /* extent record for catalog file */
 651 } __attribute__((aligned(2), packed));
 652 typedef struct HFSMasterDirectoryBlock  HFSMasterDirectoryBlock;
 653
 654
 655 #ifdef __APPLE_API_UNSTABLE
 656 #define SET_HFS_TEXT_ENCODING(hint)  \
 657         (0x656e6300 | ((hint) & 0xff))
 658 #define GET_HFS_TEXT_ENCODING(hint)  \
 659         (((hint) & 0xffffff00) == 0x656e6300 ? (hint) & 0x000000ff : 0xffffffffU)
 660 #endif /* __APPLE_API_UNSTABLE */
 661
 662
 663 /* HFS Plus Volume Header - 512 bytes */
 664 /* Stored at sector #2 (3rd sector) and second-to-last sector. */
 665 struct HFSPlusVolumeHeader {
 666         u_int16_t       signature;              /* == kHFSPlusSigWord */
 667         u_int16_t       version;                /* == kHFSPlusVersion */
 668         u_int32_t       attributes;             /* volume attributes */
 669         u_int32_t       lastMountedVersion;     /* implementation version which last mounted volume */
 670         u_int32_t       journalInfoBlock;       /* block addr of journal info (if volume is journaled, zero otherwise) */
 671
 672         u_int32_t       createDate;             /* date and time of volume creation */
 673         u_int32_t       modifyDate;             /* date and time of last modification */
 674         u_int32_t       backupDate;             /* date and time of last backup */
 675         u_int32_t       checkedDate;            /* date and time of last disk check */
 676
 677         u_int32_t       fileCount;              /* number of files in volume */
 678         u_int32_t       folderCount;            /* number of directories in volume */
 679
 680         u_int32_t       blockSize;              /* size (in bytes) of allocation blocks */
 681         u_int32_t       totalBlocks;            /* number of allocation blocks in volume (includes this header and VBM*/
 682         u_int32_t       freeBlocks;             /* number of unused allocation blocks */
 683
 684         u_int32_t       nextAllocation;         /* start of next allocation search */
 685         u_int32_t       rsrcClumpSize;          /* default resource fork clump size */
 686         u_int32_t       dataClumpSize;          /* default data fork clump size */
 687         u_int32_t       nextCatalogID;          /* next unused catalog node ID */
 688
 689         u_int32_t       writeCount;             /* volume write count */
 690         u_int64_t       encodingsBitmap;        /* which encodings have been use  on this volume */
 691
 692         u_int8_t        finderInfo[32];         /* information used by the Finder */
 693
 694         HFSPlusForkData  allocationFile;        /* allocation bitmap file */
 695         HFSPlusForkData  extentsFile;           /* extents B-tree file */
 696         HFSPlusForkData  catalogFile;           /* catalog B-tree file */
 697         HFSPlusForkData  attributesFile;        /* extended attributes B-tree file */
 698         HFSPlusForkData  startupFile;           /* boot file (secondary loader) */
 699 } __attribute__((aligned(2), packed));
 700 typedef struct HFSPlusVolumeHeader HFSPlusVolumeHeader;
 701
 702
 703 /* B-tree structures */
 704
 705 enum BTreeKeyLimits{
 706         kMaxKeyLength   = 520
 707 };
 708
 709 union BTreeKey{
 710         u_int8_t        length8;
 711         u_int16_t       length16;
 712         u_int8_t        rawData [kMaxKeyLength+2];
 713 };
 714 typedef union BTreeKey BTreeKey;
 715
 716 /* BTNodeDescriptor -- Every B-tree node starts with these fields. */
 717 struct BTNodeDescriptor {
 718         u_int32_t       fLink;                  /* next node at this level*/
 719         u_int32_t       bLink;                  /* previous node at this level*/
 720         int8_t          kind;                   /* kind of node (leaf, index, header, map)*/
 721         u_int8_t        height;                 /* zero for header, map; child is one more than parent*/
 722         u_int16_t       numRecords;             /* number of records in this node*/
 723         u_int16_t       reserved;               /* reserved - initialized as zero */
 724 } __attribute__((aligned(2), packed));
 725 typedef struct BTNodeDescriptor BTNodeDescriptor;
 726
 727 /* Constants for BTNodeDescriptor kind */
 728 enum {
 729         kBTLeafNode     = -1,
 730         kBTIndexNode    = 0,
 731         kBTHeaderNode   = 1,
 732         kBTMapNode      = 2
 733 };
 734
 735 /* BTHeaderRec -- The first record of a B-tree header node */
 736 struct BTHeaderRec {
 737         u_int16_t       treeDepth;              /* maximum height (usually leaf nodes) */
 738         u_int32_t       rootNode;               /* node number of root node */
 739         u_int32_t       leafRecords;            /* number of leaf records in all leaf nodes */
 740         u_int32_t       firstLeafNode;          /* node number of first leaf node */
 741         u_int32_t       lastLeafNode;           /* node number of last leaf node */
 742         u_int16_t       nodeSize;               /* size of a node, in bytes */
 743         u_int16_t       maxKeyLength;           /* reserved */
 744         u_int32_t       totalNodes;             /* total number of nodes in tree */
 745         u_int32_t       freeNodes;              /* number of unused (free) nodes in tree */
 746         u_int16_t       reserved1;              /* unused */
 747         u_int32_t       clumpSize;              /* reserved */
 748         u_int8_t        btreeType;              /* reserved */
 749         u_int8_t        keyCompareType;         /* Key string Comparison Type */
 750         u_int32_t       attributes;             /* persistent attributes about the tree */
 751         u_int32_t       reserved3[16];          /* reserved */
 752 } __attribute__((aligned(2), packed));
 753 typedef struct BTHeaderRec BTHeaderRec;
 754
 755 /* Constants for BTHeaderRec attributes */
 756 enum {
 757         kBTBadCloseMask          = 0x00000001,  /* reserved */
 758         kBTBigKeysMask           = 0x00000002,  /* key length field is 16 bits */
 759         kBTVariableIndexKeysMask = 0x00000004   /* keys in index nodes are variable length */
 760 };
 761
 762
 763 /* Catalog Key Name Comparison Type */
 764 enum {
 765         kHFSCaseFolding   = 0xCF,  /* case folding (case-insensitive) */
 766         kHFSBinaryCompare = 0xBC  /* binary compare (case-sensitive) */
 767 };
 768
 769 #include <uuid/uuid.h>
 770
 771 /* JournalInfoBlock - Structure that describes where our journal lives */
 772
 773 // the original size of the reserved field in the JournalInfoBlock was
 774 // 32*sizeof(u_int32_t).  To keep the total size of the structure the
 775 // same we subtract the size of new fields (currently: ext_jnl_uuid and
 776 // machine_uuid).  If you add additional fields, place them before the
 777 // reserved field and subtract their size in this macro.
 778 //
 779 #define JIB_RESERVED_SIZE  ((32*sizeof(u_int32_t)) - sizeof(uuid_string_t) - 48)
 780
 781 struct JournalInfoBlock {
 782         u_int32_t       flags;
 783         u_int32_t       device_signature[8];  // signature used to locate our device.
 784         u_int64_t       offset;               // byte offset to the journal on the device
 785         u_int64_t       size;                 // size in bytes of the journal
 786         uuid_string_t   ext_jnl_uuid;
 787         char            machine_serial_num[48];
 788         char            reserved[JIB_RESERVED_SIZE];
 789 } __attribute__((aligned(2), packed));
 790 typedef struct JournalInfoBlock JournalInfoBlock;
 791
 792 enum {
 793     kJIJournalInFSMask          = 0x00000001,
 794     kJIJournalOnOtherDeviceMask = 0x00000002,
 795     kJIJournalNeedInitMask      = 0x00000004
 796 };
 797
 798 //
 799 // This the content type uuid for "external journal" GPT
 800 // partitions.  Each instance of a partition also has a
 801 // uuid that uniquely identifies that instance.
 802 //
 803 #define EXTJNL_CONTENT_TYPE_UUID "4A6F7572-6E61-11AA-AA11-00306543ECAC"
 804
 805
 806 #ifdef __cplusplus
 807 }
 808 #endif
 809
 810 #endif /* __HFS_FORMAT__ */