The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/fs/ntfs/layout.h

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    1 /*
    2  * layout.h - All NTFS associated on-disk structures. Part of the Linux-NTFS
    3  *            project.
    4  *
    5  * Copyright (c) 2001-2005 Anton Altaparmakov
    6  * Copyright (c) 2002 Richard Russon
    7  *
    8  * This program/include file is free software; you can redistribute it and/or
    9  * modify it under the terms of the GNU General Public License as published
   10  * by the Free Software Foundation; either version 2 of the License, or
   11  * (at your option) any later version.
   12  *
   13  * This program/include file is distributed in the hope that it will be
   14  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
   15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   16  * GNU General Public License for more details.
   17  *
   18  * You should have received a copy of the GNU General Public License
   19  * along with this program (in the main directory of the Linux-NTFS
   20  * distribution in the file COPYING); if not, write to the Free Software
   21  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   22  */
   23 
   24 #ifndef _LINUX_NTFS_LAYOUT_H
   25 #define _LINUX_NTFS_LAYOUT_H
   26 
   27 #include <linux/types.h>
   28 #include <linux/bitops.h>
   29 #include <linux/list.h>
   30 #include <asm/byteorder.h>
   31 
   32 #include "types.h"
   33 
   34 /* The NTFS oem_id "NTFS    " */
   35 #define magicNTFS       cpu_to_le64(0x202020205346544eULL)
   36 
   37 /*
   38  * Location of bootsector on partition:
   39  *      The standard NTFS_BOOT_SECTOR is on sector 0 of the partition.
   40  *      On NT4 and above there is one backup copy of the boot sector to
   41  *      be found on the last sector of the partition (not normally accessible
   42  *      from within Windows as the bootsector contained number of sectors
   43  *      value is one less than the actual value!).
   44  *      On versions of NT 3.51 and earlier, the backup copy was located at
   45  *      number of sectors/2 (integer divide), i.e. in the middle of the volume.
   46  */
   47 
   48 /*
   49  * BIOS parameter block (bpb) structure.
   50  */
   51 typedef struct {
   52         le16 bytes_per_sector;          /* Size of a sector in bytes. */
   53         u8  sectors_per_cluster;        /* Size of a cluster in sectors. */
   54         le16 reserved_sectors;          /* zero */
   55         u8  fats;                       /* zero */
   56         le16 root_entries;              /* zero */
   57         le16 sectors;                   /* zero */
   58         u8  media_type;                 /* 0xf8 = hard disk */
   59         le16 sectors_per_fat;           /* zero */
   60         le16 sectors_per_track;         /* irrelevant */
   61         le16 heads;                     /* irrelevant */
   62         le32 hidden_sectors;            /* zero */
   63         le32 large_sectors;             /* zero */
   64 } __attribute__ ((__packed__)) BIOS_PARAMETER_BLOCK;
   65 
   66 /*
   67  * NTFS boot sector structure.
   68  */
   69 typedef struct {
   70         u8  jump[3];                    /* Irrelevant (jump to boot up code).*/
   71         le64 oem_id;                    /* Magic "NTFS    ". */
   72         BIOS_PARAMETER_BLOCK bpb;       /* See BIOS_PARAMETER_BLOCK. */
   73         u8  unused[4];                  /* zero, NTFS diskedit.exe states that
   74                                            this is actually:
   75                                                 __u8 physical_drive;    // 0x80
   76                                                 __u8 current_head;      // zero
   77                                                 __u8 extended_boot_signature;
   78                                                                         // 0x80
   79                                                 __u8 unused;            // zero
   80                                          */
   81 /*0x28*/sle64 number_of_sectors;        /* Number of sectors in volume. Gives
   82                                            maximum volume size of 2^63 sectors.
   83                                            Assuming standard sector size of 512
   84                                            bytes, the maximum byte size is
   85                                            approx. 4.7x10^21 bytes. (-; */
   86         sle64 mft_lcn;                  /* Cluster location of mft data. */
   87         sle64 mftmirr_lcn;              /* Cluster location of copy of mft. */
   88         s8  clusters_per_mft_record;    /* Mft record size in clusters. */
   89         u8  reserved0[3];               /* zero */
   90         s8  clusters_per_index_record;  /* Index block size in clusters. */
   91         u8  reserved1[3];               /* zero */
   92         le64 volume_serial_number;      /* Irrelevant (serial number). */
   93         le32 checksum;                  /* Boot sector checksum. */
   94 /*0x54*/u8  bootstrap[426];             /* Irrelevant (boot up code). */
   95         le16 end_of_sector_marker;      /* End of bootsector magic. Always is
   96                                            0xaa55 in little endian. */
   97 /* sizeof() = 512 (0x200) bytes */
   98 } __attribute__ ((__packed__)) NTFS_BOOT_SECTOR;
   99 
  100 /*
  101  * Magic identifiers present at the beginning of all ntfs record containing
  102  * records (like mft records for example).
  103  */
  104 enum {
  105         /* Found in $MFT/$DATA. */
  106         magic_FILE = cpu_to_le32(0x454c4946), /* Mft entry. */
  107         magic_INDX = cpu_to_le32(0x58444e49), /* Index buffer. */
  108         magic_HOLE = cpu_to_le32(0x454c4f48), /* ? (NTFS 3.0+?) */
  109 
  110         /* Found in $LogFile/$DATA. */
  111         magic_RSTR = cpu_to_le32(0x52545352), /* Restart page. */
  112         magic_RCRD = cpu_to_le32(0x44524352), /* Log record page. */
  113 
  114         /* Found in $LogFile/$DATA.  (May be found in $MFT/$DATA, also?) */
  115         magic_CHKD = cpu_to_le32(0x444b4843), /* Modified by chkdsk. */
  116 
  117         /* Found in all ntfs record containing records. */
  118         magic_BAAD = cpu_to_le32(0x44414142), /* Failed multi sector
  119                                                        transfer was detected. */
  120         /*
  121          * Found in $LogFile/$DATA when a page is full of 0xff bytes and is
  122          * thus not initialized.  Page must be initialized before using it.
  123          */
  124         magic_empty = cpu_to_le32(0xffffffff) /* Record is empty. */
  125 };
  126 
  127 typedef le32 NTFS_RECORD_TYPE;
  128 
  129 /*
  130  * Generic magic comparison macros. Finally found a use for the ## preprocessor
  131  * operator! (-8
  132  */
  133 
  134 static inline bool __ntfs_is_magic(le32 x, NTFS_RECORD_TYPE r)
  135 {
  136         return (x == r);
  137 }
  138 #define ntfs_is_magic(x, m)     __ntfs_is_magic(x, magic_##m)
  139 
  140 static inline bool __ntfs_is_magicp(le32 *p, NTFS_RECORD_TYPE r)
  141 {
  142         return (*p == r);
  143 }
  144 #define ntfs_is_magicp(p, m)    __ntfs_is_magicp(p, magic_##m)
  145 
  146 /*
  147  * Specialised magic comparison macros for the NTFS_RECORD_TYPEs defined above.
  148  */
  149 #define ntfs_is_file_record(x)          ( ntfs_is_magic (x, FILE) )
  150 #define ntfs_is_file_recordp(p)         ( ntfs_is_magicp(p, FILE) )
  151 #define ntfs_is_mft_record(x)           ( ntfs_is_file_record (x) )
  152 #define ntfs_is_mft_recordp(p)          ( ntfs_is_file_recordp(p) )
  153 #define ntfs_is_indx_record(x)          ( ntfs_is_magic (x, INDX) )
  154 #define ntfs_is_indx_recordp(p)         ( ntfs_is_magicp(p, INDX) )
  155 #define ntfs_is_hole_record(x)          ( ntfs_is_magic (x, HOLE) )
  156 #define ntfs_is_hole_recordp(p)         ( ntfs_is_magicp(p, HOLE) )
  157 
  158 #define ntfs_is_rstr_record(x)          ( ntfs_is_magic (x, RSTR) )
  159 #define ntfs_is_rstr_recordp(p)         ( ntfs_is_magicp(p, RSTR) )
  160 #define ntfs_is_rcrd_record(x)          ( ntfs_is_magic (x, RCRD) )
  161 #define ntfs_is_rcrd_recordp(p)         ( ntfs_is_magicp(p, RCRD) )
  162 
  163 #define ntfs_is_chkd_record(x)          ( ntfs_is_magic (x, CHKD) )
  164 #define ntfs_is_chkd_recordp(p)         ( ntfs_is_magicp(p, CHKD) )
  165 
  166 #define ntfs_is_baad_record(x)          ( ntfs_is_magic (x, BAAD) )
  167 #define ntfs_is_baad_recordp(p)         ( ntfs_is_magicp(p, BAAD) )
  168 
  169 #define ntfs_is_empty_record(x)         ( ntfs_is_magic (x, empty) )
  170 #define ntfs_is_empty_recordp(p)        ( ntfs_is_magicp(p, empty) )
  171 
  172 /*
  173  * The Update Sequence Array (usa) is an array of the le16 values which belong
  174  * to the end of each sector protected by the update sequence record in which
  175  * this array is contained. Note that the first entry is the Update Sequence
  176  * Number (usn), a cyclic counter of how many times the protected record has
  177  * been written to disk. The values 0 and -1 (ie. 0xffff) are not used. All
  178  * last le16's of each sector have to be equal to the usn (during reading) or
  179  * are set to it (during writing). If they are not, an incomplete multi sector
  180  * transfer has occurred when the data was written.
  181  * The maximum size for the update sequence array is fixed to:
  182  *      maximum size = usa_ofs + (usa_count * 2) = 510 bytes
  183  * The 510 bytes comes from the fact that the last le16 in the array has to
  184  * (obviously) finish before the last le16 of the first 512-byte sector.
  185  * This formula can be used as a consistency check in that usa_ofs +
  186  * (usa_count * 2) has to be less than or equal to 510.
  187  */
  188 typedef struct {
  189         NTFS_RECORD_TYPE magic; /* A four-byte magic identifying the record
  190                                    type and/or status. */
  191         le16 usa_ofs;           /* Offset to the Update Sequence Array (usa)
  192                                    from the start of the ntfs record. */
  193         le16 usa_count;         /* Number of le16 sized entries in the usa
  194                                    including the Update Sequence Number (usn),
  195                                    thus the number of fixups is the usa_count
  196                                    minus 1. */
  197 } __attribute__ ((__packed__)) NTFS_RECORD;
  198 
  199 /*
  200  * System files mft record numbers. All these files are always marked as used
  201  * in the bitmap attribute of the mft; presumably in order to avoid accidental
  202  * allocation for random other mft records. Also, the sequence number for each
  203  * of the system files is always equal to their mft record number and it is
  204  * never modified.
  205  */
  206 typedef enum {
  207         FILE_MFT       = 0,     /* Master file table (mft). Data attribute
  208                                    contains the entries and bitmap attribute
  209                                    records which ones are in use (bit==1). */
  210         FILE_MFTMirr   = 1,     /* Mft mirror: copy of first four mft records
  211                                    in data attribute. If cluster size > 4kiB,
  212                                    copy of first N mft records, with
  213                                         N = cluster_size / mft_record_size. */
  214         FILE_LogFile   = 2,     /* Journalling log in data attribute. */
  215         FILE_Volume    = 3,     /* Volume name attribute and volume information
  216                                    attribute (flags and ntfs version). Windows
  217                                    refers to this file as volume DASD (Direct
  218                                    Access Storage Device). */
  219         FILE_AttrDef   = 4,     /* Array of attribute definitions in data
  220                                    attribute. */
  221         FILE_root      = 5,     /* Root directory. */
  222         FILE_Bitmap    = 6,     /* Allocation bitmap of all clusters (lcns) in
  223                                    data attribute. */
  224         FILE_Boot      = 7,     /* Boot sector (always at cluster 0) in data
  225                                    attribute. */
  226         FILE_BadClus   = 8,     /* Contains all bad clusters in the non-resident
  227                                    data attribute. */
  228         FILE_Secure    = 9,     /* Shared security descriptors in data attribute
  229                                    and two indexes into the descriptors.
  230                                    Appeared in Windows 2000. Before that, this
  231                                    file was named $Quota but was unused. */
  232         FILE_UpCase    = 10,    /* Uppercase equivalents of all 65536 Unicode
  233                                    characters in data attribute. */
  234         FILE_Extend    = 11,    /* Directory containing other system files (eg.
  235                                    $ObjId, $Quota, $Reparse and $UsnJrnl). This
  236                                    is new to NTFS3.0. */
  237         FILE_reserved12 = 12,   /* Reserved for future use (records 12-15). */
  238         FILE_reserved13 = 13,
  239         FILE_reserved14 = 14,
  240         FILE_reserved15 = 15,
  241         FILE_first_user = 16,   /* First user file, used as test limit for
  242                                    whether to allow opening a file or not. */
  243 } NTFS_SYSTEM_FILES;
  244 
  245 /*
  246  * These are the so far known MFT_RECORD_* flags (16-bit) which contain
  247  * information about the mft record in which they are present.
  248  */
  249 enum {
  250         MFT_RECORD_IN_USE       = cpu_to_le16(0x0001),
  251         MFT_RECORD_IS_DIRECTORY = cpu_to_le16(0x0002),
  252 } __attribute__ ((__packed__));
  253 
  254 typedef le16 MFT_RECORD_FLAGS;
  255 
  256 /*
  257  * mft references (aka file references or file record segment references) are
  258  * used whenever a structure needs to refer to a record in the mft.
  259  *
  260  * A reference consists of a 48-bit index into the mft and a 16-bit sequence
  261  * number used to detect stale references.
  262  *
  263  * For error reporting purposes we treat the 48-bit index as a signed quantity.
  264  *
  265  * The sequence number is a circular counter (skipping 0) describing how many
  266  * times the referenced mft record has been (re)used. This has to match the
  267  * sequence number of the mft record being referenced, otherwise the reference
  268  * is considered stale and removed (FIXME: only ntfsck or the driver itself?).
  269  *
  270  * If the sequence number is zero it is assumed that no sequence number
  271  * consistency checking should be performed.
  272  *
  273  * FIXME: Since inodes are 32-bit as of now, the driver needs to always check
  274  * for high_part being 0 and if not either BUG(), cause a panic() or handle
  275  * the situation in some other way. This shouldn't be a problem as a volume has
  276  * to become HUGE in order to need more than 32-bits worth of mft records.
  277  * Assuming the standard mft record size of 1kb only the records (never mind
  278  * the non-resident attributes, etc.) would require 4Tb of space on their own
  279  * for the first 32 bits worth of records. This is only if some strange person
  280  * doesn't decide to foul play and make the mft sparse which would be a really
  281  * horrible thing to do as it would trash our current driver implementation. )-:
  282  * Do I hear screams "we want 64-bit inodes!" ?!? (-;
  283  *
  284  * FIXME: The mft zone is defined as the first 12% of the volume. This space is
  285  * reserved so that the mft can grow contiguously and hence doesn't become
  286  * fragmented. Volume free space includes the empty part of the mft zone and
  287  * when the volume's free 88% are used up, the mft zone is shrunk by a factor
  288  * of 2, thus making more space available for more files/data. This process is
  289  * repeated every time there is no more free space except for the mft zone until
  290  * there really is no more free space.
  291  */
  292 
  293 /*
  294  * Typedef the MFT_REF as a 64-bit value for easier handling.
  295  * Also define two unpacking macros to get to the reference (MREF) and
  296  * sequence number (MSEQNO) respectively.
  297  * The _LE versions are to be applied on little endian MFT_REFs.
  298  * Note: The _LE versions will return a CPU endian formatted value!
  299  */
  300 #define MFT_REF_MASK_CPU 0x0000ffffffffffffULL
  301 #define MFT_REF_MASK_LE cpu_to_le64(MFT_REF_MASK_CPU)
  302 
  303 typedef u64 MFT_REF;
  304 typedef le64 leMFT_REF;
  305 
  306 #define MK_MREF(m, s)   ((MFT_REF)(((MFT_REF)(s) << 48) |               \
  307                                         ((MFT_REF)(m) & MFT_REF_MASK_CPU)))
  308 #define MK_LE_MREF(m, s) cpu_to_le64(MK_MREF(m, s))
  309 
  310 #define MREF(x)         ((unsigned long)((x) & MFT_REF_MASK_CPU))
  311 #define MSEQNO(x)       ((u16)(((x) >> 48) & 0xffff))
  312 #define MREF_LE(x)      ((unsigned long)(le64_to_cpu(x) & MFT_REF_MASK_CPU))
  313 #define MSEQNO_LE(x)    ((u16)((le64_to_cpu(x) >> 48) & 0xffff))
  314 
  315 #define IS_ERR_MREF(x)  (((x) & 0x0000800000000000ULL) ? true : false)
  316 #define ERR_MREF(x)     ((u64)((s64)(x)))
  317 #define MREF_ERR(x)     ((int)((s64)(x)))
  318 
  319 /*
  320  * The mft record header present at the beginning of every record in the mft.
  321  * This is followed by a sequence of variable length attribute records which
  322  * is terminated by an attribute of type AT_END which is a truncated attribute
  323  * in that it only consists of the attribute type code AT_END and none of the
  324  * other members of the attribute structure are present.
  325  */
  326 typedef struct {
  327 /*Ofs*/
  328 /*  0   NTFS_RECORD; -- Unfolded here as gcc doesn't like unnamed structs. */
  329         NTFS_RECORD_TYPE magic; /* Usually the magic is "FILE". */
  330         le16 usa_ofs;           /* See NTFS_RECORD definition above. */
  331         le16 usa_count;         /* See NTFS_RECORD definition above. */
  332 
  333 /*  8*/ le64 lsn;               /* $LogFile sequence number for this record.
  334                                    Changed every time the record is modified. */
  335 /* 16*/ le16 sequence_number;   /* Number of times this mft record has been
  336                                    reused. (See description for MFT_REF
  337                                    above.) NOTE: The increment (skipping zero)
  338                                    is done when the file is deleted. NOTE: If
  339                                    this is zero it is left zero. */
  340 /* 18*/ le16 link_count;        /* Number of hard links, i.e. the number of
  341                                    directory entries referencing this record.
  342                                    NOTE: Only used in mft base records.
  343                                    NOTE: When deleting a directory entry we
  344                                    check the link_count and if it is 1 we
  345                                    delete the file. Otherwise we delete the
  346                                    FILE_NAME_ATTR being referenced by the
  347                                    directory entry from the mft record and
  348                                    decrement the link_count.
  349                                    FIXME: Careful with Win32 + DOS names! */
  350 /* 20*/ le16 attrs_offset;      /* Byte offset to the first attribute in this
  351                                    mft record from the start of the mft record.
  352                                    NOTE: Must be aligned to 8-byte boundary. */
  353 /* 22*/ MFT_RECORD_FLAGS flags; /* Bit array of MFT_RECORD_FLAGS. When a file
  354                                    is deleted, the MFT_RECORD_IN_USE flag is
  355                                    set to zero. */
  356 /* 24*/ le32 bytes_in_use;      /* Number of bytes used in this mft record.
  357                                    NOTE: Must be aligned to 8-byte boundary. */
  358 /* 28*/ le32 bytes_allocated;   /* Number of bytes allocated for this mft
  359                                    record. This should be equal to the mft
  360                                    record size. */
  361 /* 32*/ leMFT_REF base_mft_record;/* This is zero for base mft records.
  362                                    When it is not zero it is a mft reference
  363                                    pointing to the base mft record to which
  364                                    this record belongs (this is then used to
  365                                    locate the attribute list attribute present
  366                                    in the base record which describes this
  367                                    extension record and hence might need
  368                                    modification when the extension record
  369                                    itself is modified, also locating the
  370                                    attribute list also means finding the other
  371                                    potential extents, belonging to the non-base
  372                                    mft record). */
  373 /* 40*/ le16 next_attr_instance;/* The instance number that will be assigned to
  374                                    the next attribute added to this mft record.
  375                                    NOTE: Incremented each time after it is used.
  376                                    NOTE: Every time the mft record is reused
  377                                    this number is set to zero.  NOTE: The first
  378                                    instance number is always 0. */
  379 /* The below fields are specific to NTFS 3.1+ (Windows XP and above): */
  380 /* 42*/ le16 reserved;          /* Reserved/alignment. */
  381 /* 44*/ le32 mft_record_number; /* Number of this mft record. */
  382 /* sizeof() = 48 bytes */
  383 /*
  384  * When (re)using the mft record, we place the update sequence array at this
  385  * offset, i.e. before we start with the attributes.  This also makes sense,
  386  * otherwise we could run into problems with the update sequence array
  387  * containing in itself the last two bytes of a sector which would mean that
  388  * multi sector transfer protection wouldn't work.  As you can't protect data
  389  * by overwriting it since you then can't get it back...
  390  * When reading we obviously use the data from the ntfs record header.
  391  */
  392 } __attribute__ ((__packed__)) MFT_RECORD;
  393 
  394 /* This is the version without the NTFS 3.1+ specific fields. */
  395 typedef struct {
  396 /*Ofs*/
  397 /*  0   NTFS_RECORD; -- Unfolded here as gcc doesn't like unnamed structs. */
  398         NTFS_RECORD_TYPE magic; /* Usually the magic is "FILE". */
  399         le16 usa_ofs;           /* See NTFS_RECORD definition above. */
  400         le16 usa_count;         /* See NTFS_RECORD definition above. */
  401 
  402 /*  8*/ le64 lsn;               /* $LogFile sequence number for this record.
  403                                    Changed every time the record is modified. */
  404 /* 16*/ le16 sequence_number;   /* Number of times this mft record has been
  405                                    reused. (See description for MFT_REF
  406                                    above.) NOTE: The increment (skipping zero)
  407                                    is done when the file is deleted. NOTE: If
  408                                    this is zero it is left zero. */
  409 /* 18*/ le16 link_count;        /* Number of hard links, i.e. the number of
  410                                    directory entries referencing this record.
  411                                    NOTE: Only used in mft base records.
  412                                    NOTE: When deleting a directory entry we
  413                                    check the link_count and if it is 1 we
  414                                    delete the file. Otherwise we delete the
  415                                    FILE_NAME_ATTR being referenced by the
  416                                    directory entry from the mft record and
  417                                    decrement the link_count.
  418                                    FIXME: Careful with Win32 + DOS names! */
  419 /* 20*/ le16 attrs_offset;      /* Byte offset to the first attribute in this
  420                                    mft record from the start of the mft record.
  421                                    NOTE: Must be aligned to 8-byte boundary. */
  422 /* 22*/ MFT_RECORD_FLAGS flags; /* Bit array of MFT_RECORD_FLAGS. When a file
  423                                    is deleted, the MFT_RECORD_IN_USE flag is
  424                                    set to zero. */
  425 /* 24*/ le32 bytes_in_use;      /* Number of bytes used in this mft record.
  426                                    NOTE: Must be aligned to 8-byte boundary. */
  427 /* 28*/ le32 bytes_allocated;   /* Number of bytes allocated for this mft
  428                                    record. This should be equal to the mft
  429                                    record size. */
  430 /* 32*/ leMFT_REF base_mft_record;/* This is zero for base mft records.
  431                                    When it is not zero it is a mft reference
  432                                    pointing to the base mft record to which
  433                                    this record belongs (this is then used to
  434                                    locate the attribute list attribute present
  435                                    in the base record which describes this
  436                                    extension record and hence might need
  437                                    modification when the extension record
  438                                    itself is modified, also locating the
  439                                    attribute list also means finding the other
  440                                    potential extents, belonging to the non-base
  441                                    mft record). */
  442 /* 40*/ le16 next_attr_instance;/* The instance number that will be assigned to
  443                                    the next attribute added to this mft record.
  444                                    NOTE: Incremented each time after it is used.
  445                                    NOTE: Every time the mft record is reused
  446                                    this number is set to zero.  NOTE: The first
  447                                    instance number is always 0. */
  448 /* sizeof() = 42 bytes */
  449 /*
  450  * When (re)using the mft record, we place the update sequence array at this
  451  * offset, i.e. before we start with the attributes.  This also makes sense,
  452  * otherwise we could run into problems with the update sequence array
  453  * containing in itself the last two bytes of a sector which would mean that
  454  * multi sector transfer protection wouldn't work.  As you can't protect data
  455  * by overwriting it since you then can't get it back...
  456  * When reading we obviously use the data from the ntfs record header.
  457  */
  458 } __attribute__ ((__packed__)) MFT_RECORD_OLD;
  459 
  460 /*
  461  * System defined attributes (32-bit).  Each attribute type has a corresponding
  462  * attribute name (Unicode string of maximum 64 character length) as described
  463  * by the attribute definitions present in the data attribute of the $AttrDef
  464  * system file.  On NTFS 3.0 volumes the names are just as the types are named
  465  * in the below defines exchanging AT_ for the dollar sign ($).  If that is not
  466  * a revealing choice of symbol I do not know what is... (-;
  467  */
  468 enum {
  469         AT_UNUSED                       = cpu_to_le32(         0),
  470         AT_STANDARD_INFORMATION         = cpu_to_le32(      0x10),
  471         AT_ATTRIBUTE_LIST               = cpu_to_le32(      0x20),
  472         AT_FILE_NAME                    = cpu_to_le32(      0x30),
  473         AT_OBJECT_ID                    = cpu_to_le32(      0x40),
  474         AT_SECURITY_DESCRIPTOR          = cpu_to_le32(      0x50),
  475         AT_VOLUME_NAME                  = cpu_to_le32(      0x60),
  476         AT_VOLUME_INFORMATION           = cpu_to_le32(      0x70),
  477         AT_DATA                         = cpu_to_le32(      0x80),
  478         AT_INDEX_ROOT                   = cpu_to_le32(      0x90),
  479         AT_INDEX_ALLOCATION             = cpu_to_le32(      0xa0),
  480         AT_BITMAP                       = cpu_to_le32(      0xb0),
  481         AT_REPARSE_POINT                = cpu_to_le32(      0xc0),
  482         AT_EA_INFORMATION               = cpu_to_le32(      0xd0),
  483         AT_EA                           = cpu_to_le32(      0xe0),
  484         AT_PROPERTY_SET                 = cpu_to_le32(      0xf0),
  485         AT_LOGGED_UTILITY_STREAM        = cpu_to_le32(     0x100),
  486         AT_FIRST_USER_DEFINED_ATTRIBUTE = cpu_to_le32(    0x1000),
  487         AT_END                          = cpu_to_le32(0xffffffff)
  488 };
  489 
  490 typedef le32 ATTR_TYPE;
  491 
  492 /*
  493  * The collation rules for sorting views/indexes/etc (32-bit).
  494  *
  495  * COLLATION_BINARY - Collate by binary compare where the first byte is most
  496  *      significant.
  497  * COLLATION_UNICODE_STRING - Collate Unicode strings by comparing their binary
  498  *      Unicode values, except that when a character can be uppercased, the
  499  *      upper case value collates before the lower case one.
  500  * COLLATION_FILE_NAME - Collate file names as Unicode strings. The collation
  501  *      is done very much like COLLATION_UNICODE_STRING. In fact I have no idea
  502  *      what the difference is. Perhaps the difference is that file names
  503  *      would treat some special characters in an odd way (see
  504  *      unistr.c::ntfs_collate_names() and unistr.c::legal_ansi_char_array[]
  505  *      for what I mean but COLLATION_UNICODE_STRING would not give any special
  506  *      treatment to any characters at all, but this is speculation.
  507  * COLLATION_NTOFS_ULONG - Sorting is done according to ascending le32 key
  508  *      values. E.g. used for $SII index in FILE_Secure, which sorts by
  509  *      security_id (le32).
  510  * COLLATION_NTOFS_SID - Sorting is done according to ascending SID values.
  511  *      E.g. used for $O index in FILE_Extend/$Quota.
  512  * COLLATION_NTOFS_SECURITY_HASH - Sorting is done first by ascending hash
  513  *      values and second by ascending security_id values. E.g. used for $SDH
  514  *      index in FILE_Secure.
  515  * COLLATION_NTOFS_ULONGS - Sorting is done according to a sequence of ascending
  516  *      le32 key values. E.g. used for $O index in FILE_Extend/$ObjId, which
  517  *      sorts by object_id (16-byte), by splitting up the object_id in four
  518  *      le32 values and using them as individual keys. E.g. take the following
  519  *      two security_ids, stored as follows on disk:
  520  *              1st: a1 61 65 b7 65 7b d4 11 9e 3d 00 e0 81 10 42 59
  521  *              2nd: 38 14 37 d2 d2 f3 d4 11 a5 21 c8 6b 79 b1 97 45
  522  *      To compare them, they are split into four le32 values each, like so:
  523  *              1st: 0xb76561a1 0x11d47b65 0xe0003d9e 0x59421081
  524  *              2nd: 0xd2371438 0x11d4f3d2 0x6bc821a5 0x4597b179
  525  *      Now, it is apparent why the 2nd object_id collates after the 1st: the
  526  *      first le32 value of the 1st object_id is less than the first le32 of
  527  *      the 2nd object_id. If the first le32 values of both object_ids were
  528  *      equal then the second le32 values would be compared, etc.
  529  */
  530 enum {
  531         COLLATION_BINARY                = cpu_to_le32(0x00),
  532         COLLATION_FILE_NAME             = cpu_to_le32(0x01),
  533         COLLATION_UNICODE_STRING        = cpu_to_le32(0x02),
  534         COLLATION_NTOFS_ULONG           = cpu_to_le32(0x10),
  535         COLLATION_NTOFS_SID             = cpu_to_le32(0x11),
  536         COLLATION_NTOFS_SECURITY_HASH   = cpu_to_le32(0x12),
  537         COLLATION_NTOFS_ULONGS          = cpu_to_le32(0x13),
  538 };
  539 
  540 typedef le32 COLLATION_RULE;
  541 
  542 /*
  543  * The flags (32-bit) describing attribute properties in the attribute
  544  * definition structure.  FIXME: This information is based on Regis's
  545  * information and, according to him, it is not certain and probably
  546  * incomplete.  The INDEXABLE flag is fairly certainly correct as only the file
  547  * name attribute has this flag set and this is the only attribute indexed in
  548  * NT4.
  549  */
  550 enum {
  551         ATTR_DEF_INDEXABLE      = cpu_to_le32(0x02), /* Attribute can be
  552                                         indexed. */
  553         ATTR_DEF_MULTIPLE       = cpu_to_le32(0x04), /* Attribute type
  554                                         can be present multiple times in the
  555                                         mft records of an inode. */
  556         ATTR_DEF_NOT_ZERO       = cpu_to_le32(0x08), /* Attribute value
  557                                         must contain at least one non-zero
  558                                         byte. */
  559         ATTR_DEF_INDEXED_UNIQUE = cpu_to_le32(0x10), /* Attribute must be
  560                                         indexed and the attribute value must be
  561                                         unique for the attribute type in all of
  562                                         the mft records of an inode. */
  563         ATTR_DEF_NAMED_UNIQUE   = cpu_to_le32(0x20), /* Attribute must be
  564                                         named and the name must be unique for
  565                                         the attribute type in all of the mft
  566                                         records of an inode. */
  567         ATTR_DEF_RESIDENT       = cpu_to_le32(0x40), /* Attribute must be
  568                                         resident. */
  569         ATTR_DEF_ALWAYS_LOG     = cpu_to_le32(0x80), /* Always log
  570                                         modifications to this attribute,
  571                                         regardless of whether it is resident or
  572                                         non-resident.  Without this, only log
  573                                         modifications if the attribute is
  574                                         resident. */
  575 };
  576 
  577 typedef le32 ATTR_DEF_FLAGS;
  578 
  579 /*
  580  * The data attribute of FILE_AttrDef contains a sequence of attribute
  581  * definitions for the NTFS volume. With this, it is supposed to be safe for an
  582  * older NTFS driver to mount a volume containing a newer NTFS version without
  583  * damaging it (that's the theory. In practice it's: not damaging it too much).
  584  * Entries are sorted by attribute type. The flags describe whether the
  585  * attribute can be resident/non-resident and possibly other things, but the
  586  * actual bits are unknown.
  587  */
  588 typedef struct {
  589 /*hex ofs*/
  590 /*  0*/ ntfschar name[0x40];            /* Unicode name of the attribute. Zero
  591                                            terminated. */
  592 /* 80*/ ATTR_TYPE type;                 /* Type of the attribute. */
  593 /* 84*/ le32 display_rule;              /* Default display rule.
  594                                            FIXME: What does it mean? (AIA) */
  595 /* 88*/ COLLATION_RULE collation_rule;  /* Default collation rule. */
  596 /* 8c*/ ATTR_DEF_FLAGS flags;           /* Flags describing the attribute. */
  597 /* 90*/ sle64 min_size;                 /* Optional minimum attribute size. */
  598 /* 98*/ sle64 max_size;                 /* Maximum size of attribute. */
  599 /* sizeof() = 0xa0 or 160 bytes */
  600 } __attribute__ ((__packed__)) ATTR_DEF;
  601 
  602 /*
  603  * Attribute flags (16-bit).
  604  */
  605 enum {
  606         ATTR_IS_COMPRESSED    = cpu_to_le16(0x0001),
  607         ATTR_COMPRESSION_MASK = cpu_to_le16(0x00ff), /* Compression method
  608                                                               mask.  Also, first
  609                                                               illegal value. */
  610         ATTR_IS_ENCRYPTED     = cpu_to_le16(0x4000),
  611         ATTR_IS_SPARSE        = cpu_to_le16(0x8000),
  612 } __attribute__ ((__packed__));
  613 
  614 typedef le16 ATTR_FLAGS;
  615 
  616 /*
  617  * Attribute compression.
  618  *
  619  * Only the data attribute is ever compressed in the current ntfs driver in
  620  * Windows. Further, compression is only applied when the data attribute is
  621  * non-resident. Finally, to use compression, the maximum allowed cluster size
  622  * on a volume is 4kib.
  623  *
  624  * The compression method is based on independently compressing blocks of X
  625  * clusters, where X is determined from the compression_unit value found in the
  626  * non-resident attribute record header (more precisely: X = 2^compression_unit
  627  * clusters). On Windows NT/2k, X always is 16 clusters (compression_unit = 4).
  628  *
  629  * There are three different cases of how a compression block of X clusters
  630  * can be stored:
  631  *
  632  *   1) The data in the block is all zero (a sparse block):
  633  *        This is stored as a sparse block in the runlist, i.e. the runlist
  634  *        entry has length = X and lcn = -1. The mapping pairs array actually
  635  *        uses a delta_lcn value length of 0, i.e. delta_lcn is not present at
  636  *        all, which is then interpreted by the driver as lcn = -1.
  637  *        NOTE: Even uncompressed files can be sparse on NTFS 3.0 volumes, then
  638  *        the same principles apply as above, except that the length is not
  639  *        restricted to being any particular value.
  640  *
  641  *   2) The data in the block is not compressed:
  642  *        This happens when compression doesn't reduce the size of the block
  643  *        in clusters. I.e. if compression has a small effect so that the
  644  *        compressed data still occupies X clusters, then the uncompressed data
  645  *        is stored in the block.
  646  *        This case is recognised by the fact that the runlist entry has
  647  *        length = X and lcn >= 0. The mapping pairs array stores this as
  648  *        normal with a run length of X and some specific delta_lcn, i.e.
  649  *        delta_lcn has to be present.
  650  *
  651  *   3) The data in the block is compressed:
  652  *        The common case. This case is recognised by the fact that the run
  653  *        list entry has length L < X and lcn >= 0. The mapping pairs array
  654  *        stores this as normal with a run length of X and some specific
  655  *        delta_lcn, i.e. delta_lcn has to be present. This runlist entry is
  656  *        immediately followed by a sparse entry with length = X - L and
  657  *        lcn = -1. The latter entry is to make up the vcn counting to the
  658  *        full compression block size X.
  659  *
  660  * In fact, life is more complicated because adjacent entries of the same type
  661  * can be coalesced. This means that one has to keep track of the number of
  662  * clusters handled and work on a basis of X clusters at a time being one
  663  * block. An example: if length L > X this means that this particular runlist
  664  * entry contains a block of length X and part of one or more blocks of length
  665  * L - X. Another example: if length L < X, this does not necessarily mean that
  666  * the block is compressed as it might be that the lcn changes inside the block
  667  * and hence the following runlist entry describes the continuation of the
  668  * potentially compressed block. The block would be compressed if the
  669  * following runlist entry describes at least X - L sparse clusters, thus
  670  * making up the compression block length as described in point 3 above. (Of
  671  * course, there can be several runlist entries with small lengths so that the
  672  * sparse entry does not follow the first data containing entry with
  673  * length < X.)
  674  *
  675  * NOTE: At the end of the compressed attribute value, there most likely is not
  676  * just the right amount of data to make up a compression block, thus this data
  677  * is not even attempted to be compressed. It is just stored as is, unless
  678  * the number of clusters it occupies is reduced when compressed in which case
  679  * it is stored as a compressed compression block, complete with sparse
  680  * clusters at the end.
  681  */
  682 
  683 /*
  684  * Flags of resident attributes (8-bit).
  685  */
  686 enum {
  687         RESIDENT_ATTR_IS_INDEXED = 0x01, /* Attribute is referenced in an index
  688                                             (has implications for deleting and
  689                                             modifying the attribute). */
  690 } __attribute__ ((__packed__));
  691 
  692 typedef u8 RESIDENT_ATTR_FLAGS;
  693 
  694 /*
  695  * Attribute record header. Always aligned to 8-byte boundary.
  696  */
  697 typedef struct {
  698 /*Ofs*/
  699 /*  0*/ ATTR_TYPE type;         /* The (32-bit) type of the attribute. */
  700 /*  4*/ le32 length;            /* Byte size of the resident part of the
  701                                    attribute (aligned to 8-byte boundary).
  702                                    Used to get to the next attribute. */
  703 /*  8*/ u8 non_resident;        /* If 0, attribute is resident.
  704                                    If 1, attribute is non-resident. */
  705 /*  9*/ u8 name_length;         /* Unicode character size of name of attribute.
  706                                    0 if unnamed. */
  707 /* 10*/ le16 name_offset;       /* If name_length != 0, the byte offset to the
  708                                    beginning of the name from the attribute
  709                                    record. Note that the name is stored as a
  710                                    Unicode string. When creating, place offset
  711                                    just at the end of the record header. Then,
  712                                    follow with attribute value or mapping pairs
  713                                    array, resident and non-resident attributes
  714                                    respectively, aligning to an 8-byte
  715                                    boundary. */
  716 /* 12*/ ATTR_FLAGS flags;       /* Flags describing the attribute. */
  717 /* 14*/ le16 instance;          /* The instance of this attribute record. This
  718                                    number is unique within this mft record (see
  719                                    MFT_RECORD/next_attribute_instance notes in
  720                                    in mft.h for more details). */
  721 /* 16*/ union {
  722                 /* Resident attributes. */
  723                 struct {
  724 /* 16 */                le32 value_length;/* Byte size of attribute value. */
  725 /* 20 */                le16 value_offset;/* Byte offset of the attribute
  726                                              value from the start of the
  727                                              attribute record. When creating,
  728                                              align to 8-byte boundary if we
  729                                              have a name present as this might
  730                                              not have a length of a multiple
  731                                              of 8-bytes. */
  732 /* 22 */                RESIDENT_ATTR_FLAGS flags; /* See above. */
  733 /* 23 */                s8 reserved;      /* Reserved/alignment to 8-byte
  734                                              boundary. */
  735                 } __attribute__ ((__packed__)) resident;
  736                 /* Non-resident attributes. */
  737                 struct {
  738 /* 16*/                 leVCN lowest_vcn;/* Lowest valid virtual cluster number
  739                                 for this portion of the attribute value or
  740                                 0 if this is the only extent (usually the
  741                                 case). - Only when an attribute list is used
  742                                 does lowest_vcn != 0 ever occur. */
  743 /* 24*/                 leVCN highest_vcn;/* Highest valid vcn of this extent of
  744                                 the attribute value. - Usually there is only one
  745                                 portion, so this usually equals the attribute
  746                                 value size in clusters minus 1. Can be -1 for
  747                                 zero length files. Can be 0 for "single extent"
  748                                 attributes. */
  749 /* 32*/                 le16 mapping_pairs_offset; /* Byte offset from the
  750                                 beginning of the structure to the mapping pairs
  751                                 array which contains the mappings between the
  752                                 vcns and the logical cluster numbers (lcns).
  753                                 When creating, place this at the end of this
  754                                 record header aligned to 8-byte boundary. */
  755 /* 34*/                 u8 compression_unit; /* The compression unit expressed
  756                                 as the log to the base 2 of the number of
  757                                 clusters in a compression unit.  0 means not
  758                                 compressed.  (This effectively limits the
  759                                 compression unit size to be a power of two
  760                                 clusters.)  WinNT4 only uses a value of 4.
  761                                 Sparse files have this set to 0 on XPSP2. */
  762 /* 35*/                 u8 reserved[5];         /* Align to 8-byte boundary. */
  763 /* The sizes below are only used when lowest_vcn is zero, as otherwise it would
  764    be difficult to keep them up-to-date.*/
  765 /* 40*/                 sle64 allocated_size;   /* Byte size of disk space
  766                                 allocated to hold the attribute value. Always
  767                                 is a multiple of the cluster size. When a file
  768                                 is compressed, this field is a multiple of the
  769                                 compression block size (2^compression_unit) and
  770                                 it represents the logically allocated space
  771                                 rather than the actual on disk usage. For this
  772                                 use the compressed_size (see below). */
  773 /* 48*/                 sle64 data_size;        /* Byte size of the attribute
  774                                 value. Can be larger than allocated_size if
  775                                 attribute value is compressed or sparse. */
  776 /* 56*/                 sle64 initialized_size; /* Byte size of initialized
  777                                 portion of the attribute value. Usually equals
  778                                 data_size. */
  779 /* sizeof(uncompressed attr) = 64*/
  780 /* 64*/                 sle64 compressed_size;  /* Byte size of the attribute
  781                                 value after compression.  Only present when
  782                                 compressed or sparse.  Always is a multiple of
  783                                 the cluster size.  Represents the actual amount
  784                                 of disk space being used on the disk. */
  785 /* sizeof(compressed attr) = 72*/
  786                 } __attribute__ ((__packed__)) non_resident;
  787         } __attribute__ ((__packed__)) data;
  788 } __attribute__ ((__packed__)) ATTR_RECORD;
  789 
  790 typedef ATTR_RECORD ATTR_REC;
  791 
  792 /*
  793  * File attribute flags (32-bit) appearing in the file_attributes fields of the
  794  * STANDARD_INFORMATION attribute of MFT_RECORDs and the FILENAME_ATTR
  795  * attributes of MFT_RECORDs and directory index entries.
  796  *
  797  * All of the below flags appear in the directory index entries but only some
  798  * appear in the STANDARD_INFORMATION attribute whilst only some others appear
  799  * in the FILENAME_ATTR attribute of MFT_RECORDs.  Unless otherwise stated the
  800  * flags appear in all of the above.
  801  */
  802 enum {
  803         FILE_ATTR_READONLY              = cpu_to_le32(0x00000001),
  804         FILE_ATTR_HIDDEN                = cpu_to_le32(0x00000002),
  805         FILE_ATTR_SYSTEM                = cpu_to_le32(0x00000004),
  806         /* Old DOS volid. Unused in NT. = cpu_to_le32(0x00000008), */
  807 
  808         FILE_ATTR_DIRECTORY             = cpu_to_le32(0x00000010),
  809         /* Note, FILE_ATTR_DIRECTORY is not considered valid in NT.  It is
  810            reserved for the DOS SUBDIRECTORY flag. */
  811         FILE_ATTR_ARCHIVE               = cpu_to_le32(0x00000020),
  812         FILE_ATTR_DEVICE                = cpu_to_le32(0x00000040),
  813         FILE_ATTR_NORMAL                = cpu_to_le32(0x00000080),
  814 
  815         FILE_ATTR_TEMPORARY             = cpu_to_le32(0x00000100),
  816         FILE_ATTR_SPARSE_FILE           = cpu_to_le32(0x00000200),
  817         FILE_ATTR_REPARSE_POINT         = cpu_to_le32(0x00000400),
  818         FILE_ATTR_COMPRESSED            = cpu_to_le32(0x00000800),
  819 
  820         FILE_ATTR_OFFLINE               = cpu_to_le32(0x00001000),
  821         FILE_ATTR_NOT_CONTENT_INDEXED   = cpu_to_le32(0x00002000),
  822         FILE_ATTR_ENCRYPTED             = cpu_to_le32(0x00004000),
  823 
  824         FILE_ATTR_VALID_FLAGS           = cpu_to_le32(0x00007fb7),
  825         /* Note, FILE_ATTR_VALID_FLAGS masks out the old DOS VolId and the
  826            FILE_ATTR_DEVICE and preserves everything else.  This mask is used
  827            to obtain all flags that are valid for reading. */
  828         FILE_ATTR_VALID_SET_FLAGS       = cpu_to_le32(0x000031a7),
  829         /* Note, FILE_ATTR_VALID_SET_FLAGS masks out the old DOS VolId, the
  830            F_A_DEVICE, F_A_DIRECTORY, F_A_SPARSE_FILE, F_A_REPARSE_POINT,
  831            F_A_COMPRESSED, and F_A_ENCRYPTED and preserves the rest.  This mask
  832            is used to obtain all flags that are valid for setting. */
  833         /*
  834          * The flag FILE_ATTR_DUP_FILENAME_INDEX_PRESENT is present in all
  835          * FILENAME_ATTR attributes but not in the STANDARD_INFORMATION
  836          * attribute of an mft record.
  837          */
  838         FILE_ATTR_DUP_FILE_NAME_INDEX_PRESENT   = cpu_to_le32(0x10000000),
  839         /* Note, this is a copy of the corresponding bit from the mft record,
  840            telling us whether this is a directory or not, i.e. whether it has
  841            an index root attribute or not. */
  842         FILE_ATTR_DUP_VIEW_INDEX_PRESENT        = cpu_to_le32(0x20000000),
  843         /* Note, this is a copy of the corresponding bit from the mft record,
  844            telling us whether this file has a view index present (eg. object id
  845            index, quota index, one of the security indexes or the encrypting
  846            filesystem related indexes). */
  847 };
  848 
  849 typedef le32 FILE_ATTR_FLAGS;
  850 
  851 /*
  852  * NOTE on times in NTFS: All times are in MS standard time format, i.e. they
  853  * are the number of 100-nanosecond intervals since 1st January 1601, 00:00:00
  854  * universal coordinated time (UTC). (In Linux time starts 1st January 1970,
  855  * 00:00:00 UTC and is stored as the number of 1-second intervals since then.)
  856  */
  857 
  858 /*
  859  * Attribute: Standard information (0x10).
  860  *
  861  * NOTE: Always resident.
  862  * NOTE: Present in all base file records on a volume.
  863  * NOTE: There is conflicting information about the meaning of each of the time
  864  *       fields but the meaning as defined below has been verified to be
  865  *       correct by practical experimentation on Windows NT4 SP6a and is hence
  866  *       assumed to be the one and only correct interpretation.
  867  */
  868 typedef struct {
  869 /*Ofs*/
  870 /*  0*/ sle64 creation_time;            /* Time file was created. Updated when
  871                                            a filename is changed(?). */
  872 /*  8*/ sle64 last_data_change_time;    /* Time the data attribute was last
  873                                            modified. */
  874 /* 16*/ sle64 last_mft_change_time;     /* Time this mft record was last
  875                                            modified. */
  876 /* 24*/ sle64 last_access_time;         /* Approximate time when the file was
  877                                            last accessed (obviously this is not
  878                                            updated on read-only volumes). In
  879                                            Windows this is only updated when
  880                                            accessed if some time delta has
  881                                            passed since the last update. Also,
  882                                            last access time updates can be
  883                                            disabled altogether for speed. */
  884 /* 32*/ FILE_ATTR_FLAGS file_attributes; /* Flags describing the file. */
  885 /* 36*/ union {
  886         /* NTFS 1.2 */
  887                 struct {
  888                 /* 36*/ u8 reserved12[12];      /* Reserved/alignment to 8-byte
  889                                                    boundary. */
  890                 } __attribute__ ((__packed__)) v1;
  891         /* sizeof() = 48 bytes */
  892         /* NTFS 3.x */
  893                 struct {
  894 /*
  895  * If a volume has been upgraded from a previous NTFS version, then these
  896  * fields are present only if the file has been accessed since the upgrade.
  897  * Recognize the difference by comparing the length of the resident attribute
  898  * value. If it is 48, then the following fields are missing. If it is 72 then
  899  * the fields are present. Maybe just check like this:
  900  *      if (resident.ValueLength < sizeof(STANDARD_INFORMATION)) {
  901  *              Assume NTFS 1.2- format.
  902  *              If (volume version is 3.x)
  903  *                      Upgrade attribute to NTFS 3.x format.
  904  *              else
  905  *                      Use NTFS 1.2- format for access.
  906  *      } else
  907  *              Use NTFS 3.x format for access.
  908  * Only problem is that it might be legal to set the length of the value to
  909  * arbitrarily large values thus spoiling this check. - But chkdsk probably
  910  * views that as a corruption, assuming that it behaves like this for all
  911  * attributes.
  912  */
  913                 /* 36*/ le32 maximum_versions;  /* Maximum allowed versions for
  914                                 file. Zero if version numbering is disabled. */
  915                 /* 40*/ le32 version_number;    /* This file's version (if any).
  916                                 Set to zero if maximum_versions is zero. */
  917                 /* 44*/ le32 class_id;          /* Class id from bidirectional
  918                                 class id index (?). */
  919                 /* 48*/ le32 owner_id;          /* Owner_id of the user owning
  920                                 the file. Translate via $Q index in FILE_Extend
  921                                 /$Quota to the quota control entry for the user
  922                                 owning the file. Zero if quotas are disabled. */
  923                 /* 52*/ le32 security_id;       /* Security_id for the file.
  924                                 Translate via $SII index and $SDS data stream
  925                                 in FILE_Secure to the security descriptor. */
  926                 /* 56*/ le64 quota_charged;     /* Byte size of the charge to
  927                                 the quota for all streams of the file. Note: Is
  928                                 zero if quotas are disabled. */
  929                 /* 64*/ leUSN usn;              /* Last update sequence number
  930                                 of the file.  This is a direct index into the
  931                                 transaction log file ($UsnJrnl).  It is zero if
  932                                 the usn journal is disabled or this file has
  933                                 not been subject to logging yet.  See usnjrnl.h
  934                                 for details. */
  935                 } __attribute__ ((__packed__)) v3;
  936         /* sizeof() = 72 bytes (NTFS 3.x) */
  937         } __attribute__ ((__packed__)) ver;
  938 } __attribute__ ((__packed__)) STANDARD_INFORMATION;
  939 
  940 /*
  941  * Attribute: Attribute list (0x20).
  942  *
  943  * - Can be either resident or non-resident.
  944  * - Value consists of a sequence of variable length, 8-byte aligned,
  945  * ATTR_LIST_ENTRY records.
  946  * - The list is not terminated by anything at all! The only way to know when
  947  * the end is reached is to keep track of the current offset and compare it to
  948  * the attribute value size.
  949  * - The attribute list attribute contains one entry for each attribute of
  950  * the file in which the list is located, except for the list attribute
  951  * itself. The list is sorted: first by attribute type, second by attribute
  952  * name (if present), third by instance number. The extents of one
  953  * non-resident attribute (if present) immediately follow after the initial
  954  * extent. They are ordered by lowest_vcn and have their instace set to zero.
  955  * It is not allowed to have two attributes with all sorting keys equal.
  956  * - Further restrictions:
  957  *      - If not resident, the vcn to lcn mapping array has to fit inside the
  958  *        base mft record.
  959  *      - The attribute list attribute value has a maximum size of 256kb. This
  960  *        is imposed by the Windows cache manager.
  961  * - Attribute lists are only used when the attributes of mft record do not
  962  * fit inside the mft record despite all attributes (that can be made
  963  * non-resident) having been made non-resident. This can happen e.g. when:
  964  *      - File has a large number of hard links (lots of file name
  965  *        attributes present).
  966  *      - The mapping pairs array of some non-resident attribute becomes so
  967  *        large due to fragmentation that it overflows the mft record.
  968  *      - The security descriptor is very complex (not applicable to
  969  *        NTFS 3.0 volumes).
  970  *      - There are many named streams.
  971  */
  972 typedef struct {
  973 /*Ofs*/
  974 /*  0*/ ATTR_TYPE type;         /* Type of referenced attribute. */
  975 /*  4*/ le16 length;            /* Byte size of this entry (8-byte aligned). */
  976 /*  6*/ u8 name_length;         /* Size in Unicode chars of the name of the
  977                                    attribute or 0 if unnamed. */
  978 /*  7*/ u8 name_offset;         /* Byte offset to beginning of attribute name
  979                                    (always set this to where the name would
  980                                    start even if unnamed). */
  981 /*  8*/ leVCN lowest_vcn;       /* Lowest virtual cluster number of this portion
  982                                    of the attribute value. This is usually 0. It
  983                                    is non-zero for the case where one attribute
  984                                    does not fit into one mft record and thus
  985                                    several mft records are allocated to hold
  986                                    this attribute. In the latter case, each mft
  987                                    record holds one extent of the attribute and
  988                                    there is one attribute list entry for each
  989                                    extent. NOTE: This is DEFINITELY a signed
  990                                    value! The windows driver uses cmp, followed
  991                                    by jg when comparing this, thus it treats it
  992                                    as signed. */
  993 /* 16*/ leMFT_REF mft_reference;/* The reference of the mft record holding
  994                                    the ATTR_RECORD for this portion of the
  995                                    attribute value. */
  996 /* 24*/ le16 instance;          /* If lowest_vcn = 0, the instance of the
  997                                    attribute being referenced; otherwise 0. */
  998 /* 26*/ ntfschar name[0];       /* Use when creating only. When reading use
  999                                    name_offset to determine the location of the
 1000                                    name. */
 1001 /* sizeof() = 26 + (attribute_name_length * 2) bytes */
 1002 } __attribute__ ((__packed__)) ATTR_LIST_ENTRY;
 1003 
 1004 /*
 1005  * The maximum allowed length for a file name.
 1006  */
 1007 #define MAXIMUM_FILE_NAME_LENGTH        255
 1008 
 1009 /*
 1010  * Possible namespaces for filenames in ntfs (8-bit).
 1011  */
 1012 enum {
 1013         FILE_NAME_POSIX         = 0x00,
 1014         /* This is the largest namespace. It is case sensitive and allows all
 1015            Unicode characters except for: '\0' and '/'.  Beware that in
 1016            WinNT/2k/2003 by default files which eg have the same name except
 1017            for their case will not be distinguished by the standard utilities
 1018            and thus a "del filename" will delete both "filename" and "fileName"
 1019            without warning.  However if for example Services For Unix (SFU) are
 1020            installed and the case sensitive option was enabled at installation
 1021            time, then you can create/access/delete such files.
 1022            Note that even SFU places restrictions on the filenames beyond the
 1023            '\0' and '/' and in particular the following set of characters is
 1024            not allowed: '"', '/', '<', '>', '\'.  All other characters,
 1025            including the ones no allowed in WIN32 namespace are allowed.
 1026            Tested with SFU 3.5 (this is now free) running on Windows XP. */
 1027         FILE_NAME_WIN32         = 0x01,
 1028         /* The standard WinNT/2k NTFS long filenames. Case insensitive.  All
 1029            Unicode chars except: '\0', '"', '*', '/', ':', '<', '>', '?', '\',
 1030            and '|'.  Further, names cannot end with a '.' or a space. */
 1031         FILE_NAME_DOS           = 0x02,
 1032         /* The standard DOS filenames (8.3 format). Uppercase only.  All 8-bit
 1033            characters greater space, except: '"', '*', '+', ',', '/', ':', ';',
 1034            '<', '=', '>', '?', and '\'. */
 1035         FILE_NAME_WIN32_AND_DOS = 0x03,
 1036         /* 3 means that both the Win32 and the DOS filenames are identical and
 1037            hence have been saved in this single filename record. */
 1038 } __attribute__ ((__packed__));
 1039 
 1040 typedef u8 FILE_NAME_TYPE_FLAGS;
 1041 
 1042 /*
 1043  * Attribute: Filename (0x30).
 1044  *
 1045  * NOTE: Always resident.
 1046  * NOTE: All fields, except the parent_directory, are only updated when the
 1047  *       filename is changed. Until then, they just become out of sync with
 1048  *       reality and the more up to date values are present in the standard
 1049  *       information attribute.
 1050  * NOTE: There is conflicting information about the meaning of each of the time
 1051  *       fields but the meaning as defined below has been verified to be
 1052  *       correct by practical experimentation on Windows NT4 SP6a and is hence
 1053  *       assumed to be the one and only correct interpretation.
 1054  */
 1055 typedef struct {
 1056 /*hex ofs*/
 1057 /*  0*/ leMFT_REF parent_directory;     /* Directory this filename is
 1058                                            referenced from. */
 1059 /*  8*/ sle64 creation_time;            /* Time file was created. */
 1060 /* 10*/ sle64 last_data_change_time;    /* Time the data attribute was last
 1061                                            modified. */
 1062 /* 18*/ sle64 last_mft_change_time;     /* Time this mft record was last
 1063                                            modified. */
 1064 /* 20*/ sle64 last_access_time;         /* Time this mft record was last
 1065                                            accessed. */
 1066 /* 28*/ sle64 allocated_size;           /* Byte size of on-disk allocated space
 1067                                            for the unnamed data attribute.  So
 1068                                            for normal $DATA, this is the
 1069                                            allocated_size from the unnamed
 1070                                            $DATA attribute and for compressed
 1071                                            and/or sparse $DATA, this is the
 1072                                            compressed_size from the unnamed
 1073                                            $DATA attribute.  For a directory or
 1074                                            other inode without an unnamed $DATA
 1075                                            attribute, this is always 0.  NOTE:
 1076                                            This is a multiple of the cluster
 1077                                            size. */
 1078 /* 30*/ sle64 data_size;                /* Byte size of actual data in unnamed
 1079                                            data attribute.  For a directory or
 1080                                            other inode without an unnamed $DATA
 1081                                            attribute, this is always 0. */
 1082 /* 38*/ FILE_ATTR_FLAGS file_attributes;        /* Flags describing the file. */
 1083 /* 3c*/ union {
 1084         /* 3c*/ struct {
 1085                 /* 3c*/ le16 packed_ea_size;    /* Size of the buffer needed to
 1086                                                    pack the extended attributes
 1087                                                    (EAs), if such are present.*/
 1088                 /* 3e*/ le16 reserved;          /* Reserved for alignment. */
 1089                 } __attribute__ ((__packed__)) ea;
 1090         /* 3c*/ struct {
 1091                 /* 3c*/ le32 reparse_point_tag; /* Type of reparse point,
 1092                                                    present only in reparse
 1093                                                    points and only if there are
 1094                                                    no EAs. */
 1095                 } __attribute__ ((__packed__)) rp;
 1096         } __attribute__ ((__packed__)) type;
 1097 /* 40*/ u8 file_name_length;                    /* Length of file name in
 1098                                                    (Unicode) characters. */
 1099 /* 41*/ FILE_NAME_TYPE_FLAGS file_name_type;    /* Namespace of the file name.*/
 1100 /* 42*/ ntfschar file_name[0];                  /* File name in Unicode. */
 1101 } __attribute__ ((__packed__)) FILE_NAME_ATTR;
 1102 
 1103 /*
 1104  * GUID structures store globally unique identifiers (GUID). A GUID is a
 1105  * 128-bit value consisting of one group of eight hexadecimal digits, followed
 1106  * by three groups of four hexadecimal digits each, followed by one group of
 1107  * twelve hexadecimal digits. GUIDs are Microsoft's implementation of the
 1108  * distributed computing environment (DCE) universally unique identifier (UUID).
 1109  * Example of a GUID:
 1110  *      1F010768-5A73-BC91-0010A52216A7
 1111  */
 1112 typedef struct {
 1113         le32 data1;     /* The first eight hexadecimal digits of the GUID. */
 1114         le16 data2;     /* The first group of four hexadecimal digits. */
 1115         le16 data3;     /* The second group of four hexadecimal digits. */
 1116         u8 data4[8];    /* The first two bytes are the third group of four
 1117                            hexadecimal digits. The remaining six bytes are the
 1118                            final 12 hexadecimal digits. */
 1119 } __attribute__ ((__packed__)) GUID;
 1120 
 1121 /*
 1122  * FILE_Extend/$ObjId contains an index named $O. This index contains all
 1123  * object_ids present on the volume as the index keys and the corresponding
 1124  * mft_record numbers as the index entry data parts. The data part (defined
 1125  * below) also contains three other object_ids:
 1126  *      birth_volume_id - object_id of FILE_Volume on which the file was first
 1127  *                        created. Optional (i.e. can be zero).
 1128  *      birth_object_id - object_id of file when it was first created. Usually
 1129  *                        equals the object_id. Optional (i.e. can be zero).
 1130  *      domain_id       - Reserved (always zero).
 1131  */
 1132 typedef struct {
 1133         leMFT_REF mft_reference;/* Mft record containing the object_id in
 1134                                    the index entry key. */
 1135         union {
 1136                 struct {
 1137                         GUID birth_volume_id;
 1138                         GUID birth_object_id;
 1139                         GUID domain_id;
 1140                 } __attribute__ ((__packed__)) origin;
 1141                 u8 extended_info[48];
 1142         } __attribute__ ((__packed__)) opt;
 1143 } __attribute__ ((__packed__)) OBJ_ID_INDEX_DATA;
 1144 
 1145 /*
 1146  * Attribute: Object id (NTFS 3.0+) (0x40).
 1147  *
 1148  * NOTE: Always resident.
 1149  */
 1150 typedef struct {
 1151         GUID object_id;                         /* Unique id assigned to the
 1152                                                    file.*/
 1153         /* The following fields are optional. The attribute value size is 16
 1154            bytes, i.e. sizeof(GUID), if these are not present at all. Note,
 1155            the entries can be present but one or more (or all) can be zero
 1156            meaning that that particular value(s) is(are) not defined. */
 1157         union {
 1158                 struct {
 1159                         GUID birth_volume_id;   /* Unique id of volume on which
 1160                                                    the file was first created.*/
 1161                         GUID birth_object_id;   /* Unique id of file when it was
 1162                                                    first created. */
 1163                         GUID domain_id;         /* Reserved, zero. */
 1164                 } __attribute__ ((__packed__)) origin;
 1165                 u8 extended_info[48];
 1166         } __attribute__ ((__packed__)) opt;
 1167 } __attribute__ ((__packed__)) OBJECT_ID_ATTR;
 1168 
 1169 /*
 1170  * The pre-defined IDENTIFIER_AUTHORITIES used as SID_IDENTIFIER_AUTHORITY in
 1171  * the SID structure (see below).
 1172  */
 1173 //typedef enum {                                        /* SID string prefix. */
 1174 //      SECURITY_NULL_SID_AUTHORITY     = {0, 0, 0, 0, 0, 0},   /* S-1-0 */
 1175 //      SECURITY_WORLD_SID_AUTHORITY    = {0, 0, 0, 0, 0, 1},   /* S-1-1 */
 1176 //      SECURITY_LOCAL_SID_AUTHORITY    = {0, 0, 0, 0, 0, 2},   /* S-1-2 */
 1177 //      SECURITY_CREATOR_SID_AUTHORITY  = {0, 0, 0, 0, 0, 3},   /* S-1-3 */
 1178 //      SECURITY_NON_UNIQUE_AUTHORITY   = {0, 0, 0, 0, 0, 4},   /* S-1-4 */
 1179 //      SECURITY_NT_SID_AUTHORITY       = {0, 0, 0, 0, 0, 5},   /* S-1-5 */
 1180 //} IDENTIFIER_AUTHORITIES;
 1181 
 1182 /*
 1183  * These relative identifiers (RIDs) are used with the above identifier
 1184  * authorities to make up universal well-known SIDs.
 1185  *
 1186  * Note: The relative identifier (RID) refers to the portion of a SID, which
 1187  * identifies a user or group in relation to the authority that issued the SID.
 1188  * For example, the universal well-known SID Creator Owner ID (S-1-3-0) is
 1189  * made up of the identifier authority SECURITY_CREATOR_SID_AUTHORITY (3) and
 1190  * the relative identifier SECURITY_CREATOR_OWNER_RID (0).
 1191  */
 1192 typedef enum {                                  /* Identifier authority. */
 1193         SECURITY_NULL_RID                 = 0,  /* S-1-0 */
 1194         SECURITY_WORLD_RID                = 0,  /* S-1-1 */
 1195         SECURITY_LOCAL_RID                = 0,  /* S-1-2 */
 1196 
 1197         SECURITY_CREATOR_OWNER_RID        = 0,  /* S-1-3 */
 1198         SECURITY_CREATOR_GROUP_RID        = 1,  /* S-1-3 */
 1199 
 1200         SECURITY_CREATOR_OWNER_SERVER_RID = 2,  /* S-1-3 */
 1201         SECURITY_CREATOR_GROUP_SERVER_RID = 3,  /* S-1-3 */
 1202 
 1203         SECURITY_DIALUP_RID               = 1,
 1204         SECURITY_NETWORK_RID              = 2,
 1205         SECURITY_BATCH_RID                = 3,
 1206         SECURITY_INTERACTIVE_RID          = 4,
 1207         SECURITY_SERVICE_RID              = 6,
 1208         SECURITY_ANONYMOUS_LOGON_RID      = 7,
 1209         SECURITY_PROXY_RID                = 8,
 1210         SECURITY_ENTERPRISE_CONTROLLERS_RID=9,
 1211         SECURITY_SERVER_LOGON_RID         = 9,
 1212         SECURITY_PRINCIPAL_SELF_RID       = 0xa,
 1213         SECURITY_AUTHENTICATED_USER_RID   = 0xb,
 1214         SECURITY_RESTRICTED_CODE_RID      = 0xc,
 1215         SECURITY_TERMINAL_SERVER_RID      = 0xd,
 1216 
 1217         SECURITY_LOGON_IDS_RID            = 5,
 1218         SECURITY_LOGON_IDS_RID_COUNT      = 3,
 1219 
 1220         SECURITY_LOCAL_SYSTEM_RID         = 0x12,
 1221 
 1222         SECURITY_NT_NON_UNIQUE            = 0x15,
 1223 
 1224         SECURITY_BUILTIN_DOMAIN_RID       = 0x20,
 1225 
 1226         /*
 1227          * Well-known domain relative sub-authority values (RIDs).
 1228          */
 1229 
 1230         /* Users. */
 1231         DOMAIN_USER_RID_ADMIN             = 0x1f4,
 1232         DOMAIN_USER_RID_GUEST             = 0x1f5,
 1233         DOMAIN_USER_RID_KRBTGT            = 0x1f6,
 1234 
 1235         /* Groups. */
 1236         DOMAIN_GROUP_RID_ADMINS           = 0x200,
 1237         DOMAIN_GROUP_RID_USERS            = 0x201,
 1238         DOMAIN_GROUP_RID_GUESTS           = 0x202,
 1239         DOMAIN_GROUP_RID_COMPUTERS        = 0x203,
 1240         DOMAIN_GROUP_RID_CONTROLLERS      = 0x204,
 1241         DOMAIN_GROUP_RID_CERT_ADMINS      = 0x205,
 1242         DOMAIN_GROUP_RID_SCHEMA_ADMINS    = 0x206,
 1243         DOMAIN_GROUP_RID_ENTERPRISE_ADMINS= 0x207,
 1244         DOMAIN_GROUP_RID_POLICY_ADMINS    = 0x208,
 1245 
 1246         /* Aliases. */
 1247         DOMAIN_ALIAS_RID_ADMINS           = 0x220,
 1248         DOMAIN_ALIAS_RID_USERS            = 0x221,
 1249         DOMAIN_ALIAS_RID_GUESTS           = 0x222,
 1250         DOMAIN_ALIAS_RID_POWER_USERS      = 0x223,
 1251 
 1252         DOMAIN_ALIAS_RID_ACCOUNT_OPS      = 0x224,
 1253         DOMAIN_ALIAS_RID_SYSTEM_OPS       = 0x225,
 1254         DOMAIN_ALIAS_RID_PRINT_OPS        = 0x226,
 1255         DOMAIN_ALIAS_RID_BACKUP_OPS       = 0x227,
 1256 
 1257         DOMAIN_ALIAS_RID_REPLICATOR       = 0x228,
 1258         DOMAIN_ALIAS_RID_RAS_SERVERS      = 0x229,
 1259         DOMAIN_ALIAS_RID_PREW2KCOMPACCESS = 0x22a,
 1260 } RELATIVE_IDENTIFIERS;
 1261 
 1262 /*
 1263  * The universal well-known SIDs:
 1264  *
 1265  *      NULL_SID                        S-1-0-0
 1266  *      WORLD_SID                       S-1-1-0
 1267  *      LOCAL_SID                       S-1-2-0
 1268  *      CREATOR_OWNER_SID               S-1-3-0
 1269  *      CREATOR_GROUP_SID               S-1-3-1
 1270  *      CREATOR_OWNER_SERVER_SID        S-1-3-2
 1271  *      CREATOR_GROUP_SERVER_SID        S-1-3-3
 1272  *
 1273  *      (Non-unique IDs)                S-1-4
 1274  *
 1275  * NT well-known SIDs:
 1276  *
 1277  *      NT_AUTHORITY_SID        S-1-5
 1278  *      DIALUP_SID              S-1-5-1
 1279  *
 1280  *      NETWORD_SID             S-1-5-2
 1281  *      BATCH_SID               S-1-5-3
 1282  *      INTERACTIVE_SID         S-1-5-4
 1283  *      SERVICE_SID             S-1-5-6
 1284  *      ANONYMOUS_LOGON_SID     S-1-5-7         (aka null logon session)
 1285  *      PROXY_SID               S-1-5-8
 1286  *      SERVER_LOGON_SID        S-1-5-9         (aka domain controller account)
 1287  *      SELF_SID                S-1-5-10        (self RID)
 1288  *      AUTHENTICATED_USER_SID  S-1-5-11
 1289  *      RESTRICTED_CODE_SID     S-1-5-12        (running restricted code)
 1290  *      TERMINAL_SERVER_SID     S-1-5-13        (running on terminal server)
 1291  *
 1292  *      (Logon IDs)             S-1-5-5-X-Y
 1293  *
 1294  *      (NT non-unique IDs)     S-1-5-0x15-...
 1295  *
 1296  *      (Built-in domain)       S-1-5-0x20
 1297  */
 1298 
 1299 /*
 1300  * The SID_IDENTIFIER_AUTHORITY is a 48-bit value used in the SID structure.
 1301  *
 1302  * NOTE: This is stored as a big endian number, hence the high_part comes
 1303  * before the low_part.
 1304  */
 1305 typedef union {
 1306         struct {
 1307                 u16 high_part;  /* High 16-bits. */
 1308                 u32 low_part;   /* Low 32-bits. */
 1309         } __attribute__ ((__packed__)) parts;
 1310         u8 value[6];            /* Value as individual bytes. */
 1311 } __attribute__ ((__packed__)) SID_IDENTIFIER_AUTHORITY;
 1312 
 1313 /*
 1314  * The SID structure is a variable-length structure used to uniquely identify
 1315  * users or groups. SID stands for security identifier.
 1316  *
 1317  * The standard textual representation of the SID is of the form:
 1318  *      S-R-I-S-S...
 1319  * Where:
 1320  *    - The first "S" is the literal character 'S' identifying the following
 1321  *      digits as a SID.
 1322  *    - R is the revision level of the SID expressed as a sequence of digits
 1323  *      either in decimal or hexadecimal (if the later, prefixed by "0x").
 1324  *    - I is the 48-bit identifier_authority, expressed as digits as R above.
 1325  *    - S... is one or more sub_authority values, expressed as digits as above.
 1326  *
 1327  * Example SID; the domain-relative SID of the local Administrators group on
 1328  * Windows NT/2k:
 1329  *      S-1-5-32-544
 1330  * This translates to a SID with:
 1331  *      revision = 1,
 1332  *      sub_authority_count = 2,
 1333  *      identifier_authority = {0,0,0,0,0,5},   // SECURITY_NT_AUTHORITY
 1334  *      sub_authority[0] = 32,                  // SECURITY_BUILTIN_DOMAIN_RID
 1335  *      sub_authority[1] = 544                  // DOMAIN_ALIAS_RID_ADMINS
 1336  */
 1337 typedef struct {
 1338         u8 revision;
 1339         u8 sub_authority_count;
 1340         SID_IDENTIFIER_AUTHORITY identifier_authority;
 1341         le32 sub_authority[1];          /* At least one sub_authority. */
 1342 } __attribute__ ((__packed__)) SID;
 1343 
 1344 /*
 1345  * Current constants for SIDs.
 1346  */
 1347 typedef enum {
 1348         SID_REVISION                    =  1,   /* Current revision level. */
 1349         SID_MAX_SUB_AUTHORITIES         = 15,   /* Maximum number of those. */
 1350         SID_RECOMMENDED_SUB_AUTHORITIES =  1,   /* Will change to around 6 in
 1351                                                    a future revision. */
 1352 } SID_CONSTANTS;
 1353 
 1354 /*
 1355  * The predefined ACE types (8-bit, see below).
 1356  */
 1357 enum {
 1358         ACCESS_MIN_MS_ACE_TYPE          = 0,
 1359         ACCESS_ALLOWED_ACE_TYPE         = 0,
 1360         ACCESS_DENIED_ACE_TYPE          = 1,
 1361         SYSTEM_AUDIT_ACE_TYPE           = 2,
 1362         SYSTEM_ALARM_ACE_TYPE           = 3, /* Not implemented as of Win2k. */
 1363         ACCESS_MAX_MS_V2_ACE_TYPE       = 3,
 1364 
 1365         ACCESS_ALLOWED_COMPOUND_ACE_TYPE= 4,
 1366         ACCESS_MAX_MS_V3_ACE_TYPE       = 4,
 1367 
 1368         /* The following are Win2k only. */
 1369         ACCESS_MIN_MS_OBJECT_ACE_TYPE   = 5,
 1370         ACCESS_ALLOWED_OBJECT_ACE_TYPE  = 5,
 1371         ACCESS_DENIED_OBJECT_ACE_TYPE   = 6,
 1372         SYSTEM_AUDIT_OBJECT_ACE_TYPE    = 7,
 1373         SYSTEM_ALARM_OBJECT_ACE_TYPE    = 8,
 1374         ACCESS_MAX_MS_OBJECT_ACE_TYPE   = 8,
 1375 
 1376         ACCESS_MAX_MS_V4_ACE_TYPE       = 8,
 1377 
 1378         /* This one is for WinNT/2k. */
 1379         ACCESS_MAX_MS_ACE_TYPE          = 8,
 1380 } __attribute__ ((__packed__));
 1381 
 1382 typedef u8 ACE_TYPES;
 1383 
 1384 /*
 1385  * The ACE flags (8-bit) for audit and inheritance (see below).
 1386  *
 1387  * SUCCESSFUL_ACCESS_ACE_FLAG is only used with system audit and alarm ACE
 1388  * types to indicate that a message is generated (in Windows!) for successful
 1389  * accesses.
 1390  *
 1391  * FAILED_ACCESS_ACE_FLAG is only used with system audit and alarm ACE types
 1392  * to indicate that a message is generated (in Windows!) for failed accesses.
 1393  */
 1394 enum {
 1395         /* The inheritance flags. */
 1396         OBJECT_INHERIT_ACE              = 0x01,
 1397         CONTAINER_INHERIT_ACE           = 0x02,
 1398         NO_PROPAGATE_INHERIT_ACE        = 0x04,
 1399         INHERIT_ONLY_ACE                = 0x08,
 1400         INHERITED_ACE                   = 0x10, /* Win2k only. */
 1401         VALID_INHERIT_FLAGS             = 0x1f,
 1402 
 1403         /* The audit flags. */
 1404         SUCCESSFUL_ACCESS_ACE_FLAG      = 0x40,
 1405         FAILED_ACCESS_ACE_FLAG          = 0x80,
 1406 } __attribute__ ((__packed__));
 1407 
 1408 typedef u8 ACE_FLAGS;
 1409 
 1410 /*
 1411  * An ACE is an access-control entry in an access-control list (ACL).
 1412  * An ACE defines access to an object for a specific user or group or defines
 1413  * the types of access that generate system-administration messages or alarms
 1414  * for a specific user or group. The user or group is identified by a security
 1415  * identifier (SID).
 1416  *
 1417  * Each ACE starts with an ACE_HEADER structure (aligned on 4-byte boundary),
 1418  * which specifies the type and size of the ACE. The format of the subsequent
 1419  * data depends on the ACE type.
 1420  */
 1421 typedef struct {
 1422 /*Ofs*/
 1423 /*  0*/ ACE_TYPES type;         /* Type of the ACE. */
 1424 /*  1*/ ACE_FLAGS flags;        /* Flags describing the ACE. */
 1425 /*  2*/ le16 size;              /* Size in bytes of the ACE. */
 1426 } __attribute__ ((__packed__)) ACE_HEADER;
 1427 
 1428 /*
 1429  * The access mask (32-bit). Defines the access rights.
 1430  *
 1431  * The specific rights (bits 0 to 15).  These depend on the type of the object
 1432  * being secured by the ACE.
 1433  */
 1434 enum {
 1435         /* Specific rights for files and directories are as follows: */
 1436 
 1437         /* Right to read data from the file. (FILE) */
 1438         FILE_READ_DATA                  = cpu_to_le32(0x00000001),
 1439         /* Right to list contents of a directory. (DIRECTORY) */
 1440         FILE_LIST_DIRECTORY             = cpu_to_le32(0x00000001),
 1441 
 1442         /* Right to write data to the file. (FILE) */
 1443         FILE_WRITE_DATA                 = cpu_to_le32(0x00000002),
 1444         /* Right to create a file in the directory. (DIRECTORY) */
 1445         FILE_ADD_FILE                   = cpu_to_le32(0x00000002),
 1446 
 1447         /* Right to append data to the file. (FILE) */
 1448         FILE_APPEND_DATA                = cpu_to_le32(0x00000004),
 1449         /* Right to create a subdirectory. (DIRECTORY) */
 1450         FILE_ADD_SUBDIRECTORY           = cpu_to_le32(0x00000004),
 1451 
 1452         /* Right to read extended attributes. (FILE/DIRECTORY) */
 1453         FILE_READ_EA                    = cpu_to_le32(0x00000008),
 1454 
 1455         /* Right to write extended attributes. (FILE/DIRECTORY) */
 1456         FILE_WRITE_EA                   = cpu_to_le32(0x00000010),
 1457 
 1458         /* Right to execute a file. (FILE) */
 1459         FILE_EXECUTE                    = cpu_to_le32(0x00000020),
 1460         /* Right to traverse the directory. (DIRECTORY) */
 1461         FILE_TRAVERSE                   = cpu_to_le32(0x00000020),
 1462 
 1463         /*
 1464          * Right to delete a directory and all the files it contains (its
 1465          * children), even if the files are read-only. (DIRECTORY)
 1466          */
 1467         FILE_DELETE_CHILD               = cpu_to_le32(0x00000040),
 1468 
 1469         /* Right to read file attributes. (FILE/DIRECTORY) */
 1470         FILE_READ_ATTRIBUTES            = cpu_to_le32(0x00000080),
 1471 
 1472         /* Right to change file attributes. (FILE/DIRECTORY) */
 1473         FILE_WRITE_ATTRIBUTES           = cpu_to_le32(0x00000100),
 1474 
 1475         /*
 1476          * The standard rights (bits 16 to 23).  These are independent of the
 1477          * type of object being secured.
 1478          */
 1479 
 1480         /* Right to delete the object. */
 1481         DELETE                          = cpu_to_le32(0x00010000),
 1482 
 1483         /*
 1484          * Right to read the information in the object's security descriptor,
 1485          * not including the information in the SACL, i.e. right to read the
 1486          * security descriptor and owner.
 1487          */
 1488         READ_CONTROL                    = cpu_to_le32(0x00020000),
 1489 
 1490         /* Right to modify the DACL in the object's security descriptor. */
 1491         WRITE_DAC                       = cpu_to_le32(0x00040000),
 1492 
 1493         /* Right to change the owner in the object's security descriptor. */
 1494         WRITE_OWNER                     = cpu_to_le32(0x00080000),
 1495 
 1496         /*
 1497          * Right to use the object for synchronization.  Enables a process to
 1498          * wait until the object is in the signalled state.  Some object types
 1499          * do not support this access right.
 1500          */
 1501         SYNCHRONIZE                     = cpu_to_le32(0x00100000),
 1502 
 1503         /*
 1504          * The following STANDARD_RIGHTS_* are combinations of the above for
 1505          * convenience and are defined by the Win32 API.
 1506          */
 1507 
 1508         /* These are currently defined to READ_CONTROL. */
 1509         STANDARD_RIGHTS_READ            = cpu_to_le32(0x00020000),
 1510         STANDARD_RIGHTS_WRITE           = cpu_to_le32(0x00020000),
 1511         STANDARD_RIGHTS_EXECUTE         = cpu_to_le32(0x00020000),
 1512 
 1513         /* Combines DELETE, READ_CONTROL, WRITE_DAC, and WRITE_OWNER access. */
 1514         STANDARD_RIGHTS_REQUIRED        = cpu_to_le32(0x000f0000),
 1515 
 1516         /*
 1517          * Combines DELETE, READ_CONTROL, WRITE_DAC, WRITE_OWNER, and
 1518          * SYNCHRONIZE access.
 1519          */
 1520         STANDARD_RIGHTS_ALL             = cpu_to_le32(0x001f0000),
 1521 
 1522         /*
 1523          * The access system ACL and maximum allowed access types (bits 24 to
 1524          * 25, bits 26 to 27 are reserved).
 1525          */
 1526         ACCESS_SYSTEM_SECURITY          = cpu_to_le32(0x01000000),
 1527         MAXIMUM_ALLOWED                 = cpu_to_le32(0x02000000),
 1528 
 1529         /*
 1530          * The generic rights (bits 28 to 31).  These map onto the standard and
 1531          * specific rights.
 1532          */
 1533 
 1534         /* Read, write, and execute access. */
 1535         GENERIC_ALL                     = cpu_to_le32(0x10000000),
 1536 
 1537         /* Execute access. */
 1538         GENERIC_EXECUTE                 = cpu_to_le32(0x20000000),
 1539 
 1540         /*
 1541          * Write access.  For files, this maps onto:
 1542          *      FILE_APPEND_DATA | FILE_WRITE_ATTRIBUTES | FILE_WRITE_DATA |
 1543          *      FILE_WRITE_EA | STANDARD_RIGHTS_WRITE | SYNCHRONIZE
 1544          * For directories, the mapping has the same numerical value.  See
 1545          * above for the descriptions of the rights granted.
 1546          */
 1547         GENERIC_WRITE                   = cpu_to_le32(0x40000000),
 1548 
 1549         /*
 1550          * Read access.  For files, this maps onto:
 1551          *      FILE_READ_ATTRIBUTES | FILE_READ_DATA | FILE_READ_EA |
 1552          *      STANDARD_RIGHTS_READ | SYNCHRONIZE
 1553          * For directories, the mapping has the same numberical value.  See
 1554          * above for the descriptions of the rights granted.
 1555          */
 1556         GENERIC_READ                    = cpu_to_le32(0x80000000),
 1557 };
 1558 
 1559 typedef le32 ACCESS_MASK;
 1560 
 1561 /*
 1562  * The generic mapping array. Used to denote the mapping of each generic
 1563  * access right to a specific access mask.
 1564  *
 1565  * FIXME: What exactly is this and what is it for? (AIA)
 1566  */
 1567 typedef struct {
 1568         ACCESS_MASK generic_read;
 1569         ACCESS_MASK generic_write;
 1570         ACCESS_MASK generic_execute;
 1571         ACCESS_MASK generic_all;
 1572 } __attribute__ ((__packed__)) GENERIC_MAPPING;
 1573 
 1574 /*
 1575  * The predefined ACE type structures are as defined below.
 1576  */
 1577 
 1578 /*
 1579  * ACCESS_ALLOWED_ACE, ACCESS_DENIED_ACE, SYSTEM_AUDIT_ACE, SYSTEM_ALARM_ACE
 1580  */
 1581 typedef struct {
 1582 /*  0   ACE_HEADER; -- Unfolded here as gcc doesn't like unnamed structs. */
 1583         ACE_TYPES type;         /* Type of the ACE. */
 1584         ACE_FLAGS flags;        /* Flags describing the ACE. */
 1585         le16 size;              /* Size in bytes of the ACE. */
 1586 /*  4*/ ACCESS_MASK mask;       /* Access mask associated with the ACE. */
 1587 
 1588 /*  8*/ SID sid;                /* The SID associated with the ACE. */
 1589 } __attribute__ ((__packed__)) ACCESS_ALLOWED_ACE, ACCESS_DENIED_ACE,
 1590                                SYSTEM_AUDIT_ACE, SYSTEM_ALARM_ACE;
 1591 
 1592 /*
 1593  * The object ACE flags (32-bit).
 1594  */
 1595 enum {
 1596         ACE_OBJECT_TYPE_PRESENT                 = cpu_to_le32(1),
 1597         ACE_INHERITED_OBJECT_TYPE_PRESENT       = cpu_to_le32(2),
 1598 };
 1599 
 1600 typedef le32 OBJECT_ACE_FLAGS;
 1601 
 1602 typedef struct {
 1603 /*  0   ACE_HEADER; -- Unfolded here as gcc doesn't like unnamed structs. */
 1604         ACE_TYPES type;         /* Type of the ACE. */
 1605         ACE_FLAGS flags;        /* Flags describing the ACE. */
 1606         le16 size;              /* Size in bytes of the ACE. */
 1607 /*  4*/ ACCESS_MASK mask;       /* Access mask associated with the ACE. */
 1608 
 1609 /*  8*/ OBJECT_ACE_FLAGS object_flags;  /* Flags describing the object ACE. */
 1610 /* 12*/ GUID object_type;
 1611 /* 28*/ GUID inherited_object_type;
 1612 
 1613 /* 44*/ SID sid;                /* The SID associated with the ACE. */
 1614 } __attribute__ ((__packed__)) ACCESS_ALLOWED_OBJECT_ACE,
 1615                                ACCESS_DENIED_OBJECT_ACE,
 1616                                SYSTEM_AUDIT_OBJECT_ACE,
 1617                                SYSTEM_ALARM_OBJECT_ACE;
 1618 
 1619 /*
 1620  * An ACL is an access-control list (ACL).
 1621  * An ACL starts with an ACL header structure, which specifies the size of
 1622  * the ACL and the number of ACEs it contains. The ACL header is followed by
 1623  * zero or more access control entries (ACEs). The ACL as well as each ACE
 1624  * are aligned on 4-byte boundaries.
 1625  */
 1626 typedef struct {
 1627         u8 revision;    /* Revision of this ACL. */
 1628         u8 alignment1;
 1629         le16 size;      /* Allocated space in bytes for ACL. Includes this
 1630                            header, the ACEs and the remaining free space. */
 1631         le16 ace_count; /* Number of ACEs in the ACL. */
 1632         le16 alignment2;
 1633 /* sizeof() = 8 bytes */
 1634 } __attribute__ ((__packed__)) ACL;
 1635 
 1636 /*
 1637  * Current constants for ACLs.
 1638  */
 1639 typedef enum {
 1640         /* Current revision. */
 1641         ACL_REVISION            = 2,
 1642         ACL_REVISION_DS         = 4,
 1643 
 1644         /* History of revisions. */
 1645         ACL_REVISION1           = 1,
 1646         MIN_ACL_REVISION        = 2,
 1647         ACL_REVISION2           = 2,
 1648         ACL_REVISION3           = 3,
 1649         ACL_REVISION4           = 4,
 1650         MAX_ACL_REVISION        = 4,
 1651 } ACL_CONSTANTS;
 1652 
 1653 /*
 1654  * The security descriptor control flags (16-bit).
 1655  *
 1656  * SE_OWNER_DEFAULTED - This boolean flag, when set, indicates that the SID
 1657  *      pointed to by the Owner field was provided by a defaulting mechanism
 1658  *      rather than explicitly provided by the original provider of the
 1659  *      security descriptor.  This may affect the treatment of the SID with
 1660  *      respect to inheritance of an owner.
 1661  *
 1662  * SE_GROUP_DEFAULTED - This boolean flag, when set, indicates that the SID in
 1663  *      the Group field was provided by a defaulting mechanism rather than
 1664  *      explicitly provided by the original provider of the security
 1665  *      descriptor.  This may affect the treatment of the SID with respect to
 1666  *      inheritance of a primary group.
 1667  *
 1668  * SE_DACL_PRESENT - This boolean flag, when set, indicates that the security
 1669  *      descriptor contains a discretionary ACL.  If this flag is set and the
 1670  *      Dacl field of the SECURITY_DESCRIPTOR is null, then a null ACL is
 1671  *      explicitly being specified.
 1672  *
 1673  * SE_DACL_DEFAULTED - This boolean flag, when set, indicates that the ACL
 1674  *      pointed to by the Dacl field was provided by a defaulting mechanism
 1675  *      rather than explicitly provided by the original provider of the
 1676  *      security descriptor.  This may affect the treatment of the ACL with
 1677  *      respect to inheritance of an ACL.  This flag is ignored if the
 1678  *      DaclPresent flag is not set.
 1679  *
 1680  * SE_SACL_PRESENT - This boolean flag, when set,  indicates that the security
 1681  *      descriptor contains a system ACL pointed to by the Sacl field.  If this
 1682  *      flag is set and the Sacl field of the SECURITY_DESCRIPTOR is null, then
 1683  *      an empty (but present) ACL is being specified.
 1684  *
 1685  * SE_SACL_DEFAULTED - This boolean flag, when set, indicates that the ACL
 1686  *      pointed to by the Sacl field was provided by a defaulting mechanism
 1687  *      rather than explicitly provided by the original provider of the
 1688  *      security descriptor.  This may affect the treatment of the ACL with
 1689  *      respect to inheritance of an ACL.  This flag is ignored if the
 1690  *      SaclPresent flag is not set.
 1691  *
 1692  * SE_SELF_RELATIVE - This boolean flag, when set, indicates that the security
 1693  *      descriptor is in self-relative form.  In this form, all fields of the
 1694  *      security descriptor are contiguous in memory and all pointer fields are
 1695  *      expressed as offsets from the beginning of the security descriptor.
 1696  */
 1697 enum {
 1698         SE_OWNER_DEFAULTED              = cpu_to_le16(0x0001),
 1699         SE_GROUP_DEFAULTED              = cpu_to_le16(0x0002),
 1700         SE_DACL_PRESENT                 = cpu_to_le16(0x0004),
 1701         SE_DACL_DEFAULTED               = cpu_to_le16(0x0008),
 1702 
 1703         SE_SACL_PRESENT                 = cpu_to_le16(0x0010),
 1704         SE_SACL_DEFAULTED               = cpu_to_le16(0x0020),
 1705 
 1706         SE_DACL_AUTO_INHERIT_REQ        = cpu_to_le16(0x0100),
 1707         SE_SACL_AUTO_INHERIT_REQ        = cpu_to_le16(0x0200),
 1708         SE_DACL_AUTO_INHERITED          = cpu_to_le16(0x0400),
 1709         SE_SACL_AUTO_INHERITED          = cpu_to_le16(0x0800),
 1710 
 1711         SE_DACL_PROTECTED               = cpu_to_le16(0x1000),
 1712         SE_SACL_PROTECTED               = cpu_to_le16(0x2000),
 1713         SE_RM_CONTROL_VALID             = cpu_to_le16(0x4000),
 1714         SE_SELF_RELATIVE                = cpu_to_le16(0x8000)
 1715 } __attribute__ ((__packed__));
 1716 
 1717 typedef le16 SECURITY_DESCRIPTOR_CONTROL;
 1718 
 1719 /*
 1720  * Self-relative security descriptor. Contains the owner and group SIDs as well
 1721  * as the sacl and dacl ACLs inside the security descriptor itself.
 1722  */
 1723 typedef struct {
 1724         u8 revision;    /* Revision level of the security descriptor. */
 1725         u8 alignment;
 1726         SECURITY_DESCRIPTOR_CONTROL control; /* Flags qualifying the type of
 1727                            the descriptor as well as the following fields. */
 1728         le32 owner;     /* Byte offset to a SID representing an object's
 1729                            owner. If this is NULL, no owner SID is present in
 1730                            the descriptor. */
 1731         le32 group;     /* Byte offset to a SID representing an object's
 1732                            primary group. If this is NULL, no primary group
 1733                            SID is present in the descriptor. */
 1734         le32 sacl;      /* Byte offset to a system ACL. Only valid, if
 1735                            SE_SACL_PRESENT is set in the control field. If
 1736                            SE_SACL_PRESENT is set but sacl is NULL, a NULL ACL
 1737                            is specified. */
 1738         le32 dacl;      /* Byte offset to a discretionary ACL. Only valid, if
 1739                            SE_DACL_PRESENT is set in the control field. If
 1740                            SE_DACL_PRESENT is set but dacl is NULL, a NULL ACL
 1741                            (unconditionally granting access) is specified. */
 1742 /* sizeof() = 0x14 bytes */
 1743 } __attribute__ ((__packed__)) SECURITY_DESCRIPTOR_RELATIVE;
 1744 
 1745 /*
 1746  * Absolute security descriptor. Does not contain the owner and group SIDs, nor
 1747  * the sacl and dacl ACLs inside the security descriptor. Instead, it contains
 1748  * pointers to these structures in memory. Obviously, absolute security
 1749  * descriptors are only useful for in memory representations of security
 1750  * descriptors. On disk, a self-relative security descriptor is used.
 1751  */
 1752 typedef struct {
 1753         u8 revision;    /* Revision level of the security descriptor. */
 1754         u8 alignment;
 1755         SECURITY_DESCRIPTOR_CONTROL control;    /* Flags qualifying the type of
 1756                            the descriptor as well as the following fields. */
 1757         SID *owner;     /* Points to a SID representing an object's owner. If
 1758                            this is NULL, no owner SID is present in the
 1759                            descriptor. */
 1760         SID *group;     /* Points to a SID representing an object's primary
 1761                            group. If this is NULL, no primary group SID is
 1762                            present in the descriptor. */
 1763         ACL *sacl;      /* Points to a system ACL. Only valid, if
 1764                            SE_SACL_PRESENT is set in the control field. If
 1765                            SE_SACL_PRESENT is set but sacl is NULL, a NULL ACL
 1766                            is specified. */
 1767         ACL *dacl;      /* Points to a discretionary ACL. Only valid, if
 1768                            SE_DACL_PRESENT is set in the control field. If
 1769                            SE_DACL_PRESENT is set but dacl is NULL, a NULL ACL
 1770                            (unconditionally granting access) is specified. */
 1771 } __attribute__ ((__packed__)) SECURITY_DESCRIPTOR;
 1772 
 1773 /*
 1774  * Current constants for security descriptors.
 1775  */
 1776 typedef enum {
 1777         /* Current revision. */
 1778         SECURITY_DESCRIPTOR_REVISION    = 1,
 1779         SECURITY_DESCRIPTOR_REVISION1   = 1,
 1780 
 1781         /* The sizes of both the absolute and relative security descriptors is
 1782            the same as pointers, at least on ia32 architecture are 32-bit. */
 1783         SECURITY_DESCRIPTOR_MIN_LENGTH  = sizeof(SECURITY_DESCRIPTOR),
 1784 } SECURITY_DESCRIPTOR_CONSTANTS;
 1785 
 1786 /*
 1787  * Attribute: Security descriptor (0x50). A standard self-relative security
 1788  * descriptor.
 1789  *
 1790  * NOTE: Can be resident or non-resident.
 1791  * NOTE: Not used in NTFS 3.0+, as security descriptors are stored centrally
 1792  * in FILE_Secure and the correct descriptor is found using the security_id
 1793  * from the standard information attribute.
 1794  */
 1795 typedef SECURITY_DESCRIPTOR_RELATIVE SECURITY_DESCRIPTOR_ATTR;
 1796 
 1797 /*
 1798  * On NTFS 3.0+, all security descriptors are stored in FILE_Secure. Only one
 1799  * referenced instance of each unique security descriptor is stored.
 1800  *
 1801  * FILE_Secure contains no unnamed data attribute, i.e. it has zero length. It
 1802  * does, however, contain two indexes ($SDH and $SII) as well as a named data
 1803  * stream ($SDS).
 1804  *
 1805  * Every unique security descriptor is assigned a unique security identifier
 1806  * (security_id, not to be confused with a SID). The security_id is unique for
 1807  * the NTFS volume and is used as an index into the $SII index, which maps
 1808  * security_ids to the security descriptor's storage location within the $SDS
 1809  * data attribute. The $SII index is sorted by ascending security_id.
 1810  *
 1811  * A simple hash is computed from each security descriptor. This hash is used
 1812  * as an index into the $SDH index, which maps security descriptor hashes to
 1813  * the security descriptor's storage location within the $SDS data attribute.
 1814  * The $SDH index is sorted by security descriptor hash and is stored in a B+
 1815  * tree. When searching $SDH (with the intent of determining whether or not a
 1816  * new security descriptor is already present in the $SDS data stream), if a
 1817  * matching hash is found, but the security descriptors do not match, the
 1818  * search in the $SDH index is continued, searching for a next matching hash.
 1819  *
 1820  * When a precise match is found, the security_id coresponding to the security
 1821  * descriptor in the $SDS attribute is read from the found $SDH index entry and
 1822  * is stored in the $STANDARD_INFORMATION attribute of the file/directory to
 1823  * which the security descriptor is being applied. The $STANDARD_INFORMATION
 1824  * attribute is present in all base mft records (i.e. in all files and
 1825  * directories).
 1826  *
 1827  * If a match is not found, the security descriptor is assigned a new unique
 1828  * security_id and is added to the $SDS data attribute. Then, entries
 1829  * referencing the this security descriptor in the $SDS data attribute are
 1830  * added to the $SDH and $SII indexes.
 1831  *
 1832  * Note: Entries are never deleted from FILE_Secure, even if nothing
 1833  * references an entry any more.
 1834  */
 1835 
 1836 /*
 1837  * This header precedes each security descriptor in the $SDS data stream.
 1838  * This is also the index entry data part of both the $SII and $SDH indexes.
 1839  */
 1840 typedef struct {
 1841         le32 hash;        /* Hash of the security descriptor. */
 1842         le32 security_id; /* The security_id assigned to the descriptor. */
 1843         le64 offset;      /* Byte offset of this entry in the $SDS stream. */
 1844         le32 length;      /* Size in bytes of this entry in $SDS stream. */
 1845 } __attribute__ ((__packed__)) SECURITY_DESCRIPTOR_HEADER;
 1846 
 1847 /*
 1848  * The $SDS data stream contains the security descriptors, aligned on 16-byte
 1849  * boundaries, sorted by security_id in a B+ tree. Security descriptors cannot
 1850  * cross 256kib boundaries (this restriction is imposed by the Windows cache
 1851  * manager). Each security descriptor is contained in a SDS_ENTRY structure.
 1852  * Also, each security descriptor is stored twice in the $SDS stream with a
 1853  * fixed offset of 0x40000 bytes (256kib, the Windows cache manager's max size)
 1854  * between them; i.e. if a SDS_ENTRY specifies an offset of 0x51d0, then the
 1855  * the first copy of the security descriptor will be at offset 0x51d0 in the
 1856  * $SDS data stream and the second copy will be at offset 0x451d0.
 1857  */
 1858 typedef struct {
 1859 /*Ofs*/
 1860 /*  0   SECURITY_DESCRIPTOR_HEADER; -- Unfolded here as gcc doesn't like
 1861                                        unnamed structs. */
 1862         le32 hash;        /* Hash of the security descriptor. */
 1863         le32 security_id; /* The security_id assigned to the descriptor. */
 1864         le64 offset;      /* Byte offset of this entry in the $SDS stream. */
 1865         le32 length;      /* Size in bytes of this entry in $SDS stream. */
 1866 /* 20*/ SECURITY_DESCRIPTOR_RELATIVE sid; /* The self-relative security
 1867                                              descriptor. */
 1868 } __attribute__ ((__packed__)) SDS_ENTRY;
 1869 
 1870 /*
 1871  * The index entry key used in the $SII index. The collation type is
 1872  * COLLATION_NTOFS_ULONG.
 1873  */
 1874 typedef struct {
 1875         le32 security_id; /* The security_id assigned to the descriptor. */
 1876 } __attribute__ ((__packed__)) SII_INDEX_KEY;
 1877 
 1878 /*
 1879  * The index entry key used in the $SDH index. The keys are sorted first by
 1880  * hash and then by security_id. The collation rule is
 1881  * COLLATION_NTOFS_SECURITY_HASH.
 1882  */
 1883 typedef struct {
 1884         le32 hash;        /* Hash of the security descriptor. */
 1885         le32 security_id; /* The security_id assigned to the descriptor. */
 1886 } __attribute__ ((__packed__)) SDH_INDEX_KEY;
 1887 
 1888 /*
 1889  * Attribute: Volume name (0x60).
 1890  *
 1891  * NOTE: Always resident.
 1892  * NOTE: Present only in FILE_Volume.
 1893  */
 1894 typedef struct {
 1895         ntfschar name[0];       /* The name of the volume in Unicode. */
 1896 } __attribute__ ((__packed__)) VOLUME_NAME;
 1897 
 1898 /*
 1899  * Possible flags for the volume (16-bit).
 1900  */
 1901 enum {
 1902         VOLUME_IS_DIRTY                 = cpu_to_le16(0x0001),
 1903         VOLUME_RESIZE_LOG_FILE          = cpu_to_le16(0x0002),
 1904         VOLUME_UPGRADE_ON_MOUNT         = cpu_to_le16(0x0004),
 1905         VOLUME_MOUNTED_ON_NT4           = cpu_to_le16(0x0008),
 1906 
 1907         VOLUME_DELETE_USN_UNDERWAY      = cpu_to_le16(0x0010),
 1908         VOLUME_REPAIR_OBJECT_ID         = cpu_to_le16(0x0020),
 1909 
 1910         VOLUME_CHKDSK_UNDERWAY          = cpu_to_le16(0x4000),
 1911         VOLUME_MODIFIED_BY_CHKDSK       = cpu_to_le16(0x8000),
 1912 
 1913         VOLUME_FLAGS_MASK               = cpu_to_le16(0xc03f),
 1914 
 1915         /* To make our life easier when checking if we must mount read-only. */
 1916         VOLUME_MUST_MOUNT_RO_MASK       = cpu_to_le16(0xc027),
 1917 } __attribute__ ((__packed__));
 1918 
 1919 typedef le16 VOLUME_FLAGS;
 1920 
 1921 /*
 1922  * Attribute: Volume information (0x70).
 1923  *
 1924  * NOTE: Always resident.
 1925  * NOTE: Present only in FILE_Volume.
 1926  * NOTE: Windows 2000 uses NTFS 3.0 while Windows NT4 service pack 6a uses
 1927  *       NTFS 1.2. I haven't personally seen other values yet.
 1928  */
 1929 typedef struct {
 1930         le64 reserved;          /* Not used (yet?). */
 1931         u8 major_ver;           /* Major version of the ntfs format. */
 1932         u8 minor_ver;           /* Minor version of the ntfs format. */
 1933         VOLUME_FLAGS flags;     /* Bit array of VOLUME_* flags. */
 1934 } __attribute__ ((__packed__)) VOLUME_INFORMATION;
 1935 
 1936 /*
 1937  * Attribute: Data attribute (0x80).
 1938  *
 1939  * NOTE: Can be resident or non-resident.
 1940  *
 1941  * Data contents of a file (i.e. the unnamed stream) or of a named stream.
 1942  */
 1943 typedef struct {
 1944         u8 data[0];             /* The file's data contents. */
 1945 } __attribute__ ((__packed__)) DATA_ATTR;
 1946 
 1947 /*
 1948  * Index header flags (8-bit).
 1949  */
 1950 enum {
 1951         /*
 1952          * When index header is in an index root attribute:
 1953          */
 1954         SMALL_INDEX = 0, /* The index is small enough to fit inside the index
 1955                             root attribute and there is no index allocation
 1956                             attribute present. */
 1957         LARGE_INDEX = 1, /* The index is too large to fit in the index root
 1958                             attribute and/or an index allocation attribute is
 1959                             present. */
 1960         /*
 1961          * When index header is in an index block, i.e. is part of index
 1962          * allocation attribute:
 1963          */
 1964         LEAF_NODE  = 0, /* This is a leaf node, i.e. there are no more nodes
 1965                            branching off it. */
 1966         INDEX_NODE = 1, /* This node indexes other nodes, i.e. it is not a leaf
 1967                            node. */
 1968         NODE_MASK  = 1, /* Mask for accessing the *_NODE bits. */
 1969 } __attribute__ ((__packed__));
 1970 
 1971 typedef u8 INDEX_HEADER_FLAGS;
 1972 
 1973 /*
 1974  * This is the header for indexes, describing the INDEX_ENTRY records, which
 1975  * follow the INDEX_HEADER. Together the index header and the index entries
 1976  * make up a complete index.
 1977  *
 1978  * IMPORTANT NOTE: The offset, length and size structure members are counted
 1979  * relative to the start of the index header structure and not relative to the
 1980  * start of the index root or index allocation structures themselves.
 1981  */
 1982 typedef struct {
 1983         le32 entries_offset;            /* Byte offset to first INDEX_ENTRY
 1984                                            aligned to 8-byte boundary. */
 1985         le32 index_length;              /* Data size of the index in bytes,
 1986                                            i.e. bytes used from allocated
 1987                                            size, aligned to 8-byte boundary. */
 1988         le32 allocated_size;            /* Byte size of this index (block),
 1989                                            multiple of 8 bytes. */
 1990         /* NOTE: For the index root attribute, the above two numbers are always
 1991            equal, as the attribute is resident and it is resized as needed. In
 1992            the case of the index allocation attribute the attribute is not
 1993            resident and hence the allocated_size is a fixed value and must
 1994            equal the index_block_size specified by the INDEX_ROOT attribute
 1995            corresponding to the INDEX_ALLOCATION attribute this INDEX_BLOCK
 1996            belongs to. */
 1997         INDEX_HEADER_FLAGS flags;       /* Bit field of INDEX_HEADER_FLAGS. */
 1998         u8 reserved[3];                 /* Reserved/align to 8-byte boundary. */
 1999 } __attribute__ ((__packed__)) INDEX_HEADER;
 2000 
 2001 /*
 2002  * Attribute: Index root (0x90).
 2003  *
 2004  * NOTE: Always resident.
 2005  *
 2006  * This is followed by a sequence of index entries (INDEX_ENTRY structures)
 2007  * as described by the index header.
 2008  *
 2009  * When a directory is small enough to fit inside the index root then this
 2010  * is the only attribute describing the directory. When the directory is too
 2011  * large to fit in the index root, on the other hand, two additional attributes
 2012  * are present: an index allocation attribute, containing sub-nodes of the B+
 2013  * directory tree (see below), and a bitmap attribute, describing which virtual
 2014  * cluster numbers (vcns) in the index allocation attribute are in use by an
 2015  * index block.
 2016  *
 2017  * NOTE: The root directory (FILE_root) contains an entry for itself. Other
 2018  * directories do not contain entries for themselves, though.
 2019  */
 2020 typedef struct {
 2021         ATTR_TYPE type;                 /* Type of the indexed attribute. Is
 2022                                            $FILE_NAME for directories, zero
 2023                                            for view indexes. No other values
 2024                                            allowed. */
 2025         COLLATION_RULE collation_rule;  /* Collation rule used to sort the
 2026                                            index entries. If type is $FILE_NAME,
 2027                                            this must be COLLATION_FILE_NAME. */
 2028         le32 index_block_size;          /* Size of each index block in bytes (in
 2029                                            the index allocation attribute). */
 2030         u8 clusters_per_index_block;    /* Cluster size of each index block (in
 2031                                            the index allocation attribute), when
 2032                                            an index block is >= than a cluster,
 2033                                            otherwise this will be the log of
 2034                                            the size (like how the encoding of
 2035                                            the mft record size and the index
 2036                                            record size found in the boot sector
 2037                                            work). Has to be a power of 2. */
 2038         u8 reserved[3];                 /* Reserved/align to 8-byte boundary. */
 2039         INDEX_HEADER index;             /* Index header describing the
 2040                                            following index entries. */
 2041 } __attribute__ ((__packed__)) INDEX_ROOT;
 2042 
 2043 /*
 2044  * Attribute: Index allocation (0xa0).
 2045  *
 2046  * NOTE: Always non-resident (doesn't make sense to be resident anyway!).
 2047  *
 2048  * This is an array of index blocks. Each index block starts with an
 2049  * INDEX_BLOCK structure containing an index header, followed by a sequence of
 2050  * index entries (INDEX_ENTRY structures), as described by the INDEX_HEADER.
 2051  */
 2052 typedef struct {
 2053 /*  0   NTFS_RECORD; -- Unfolded here as gcc doesn't like unnamed structs. */
 2054         NTFS_RECORD_TYPE magic; /* Magic is "INDX". */
 2055         le16 usa_ofs;           /* See NTFS_RECORD definition. */
 2056         le16 usa_count;         /* See NTFS_RECORD definition. */
 2057 
 2058 /*  8*/ sle64 lsn;              /* $LogFile sequence number of the last
 2059                                    modification of this index block. */
 2060 /* 16*/ leVCN index_block_vcn;  /* Virtual cluster number of the index block.
 2061                                    If the cluster_size on the volume is <= the
 2062                                    index_block_size of the directory,
 2063                                    index_block_vcn counts in units of clusters,
 2064                                    and in units of sectors otherwise. */
 2065 /* 24*/ INDEX_HEADER index;     /* Describes the following index entries. */
 2066 /* sizeof()= 40 (0x28) bytes */
 2067 /*
 2068  * When creating the index block, we place the update sequence array at this
 2069  * offset, i.e. before we start with the index entries. This also makes sense,
 2070  * otherwise we could run into problems with the update sequence array
 2071  * containing in itself the last two bytes of a sector which would mean that
 2072  * multi sector transfer protection wouldn't work. As you can't protect data
 2073  * by overwriting it since you then can't get it back...
 2074  * When reading use the data from the ntfs record header.
 2075  */
 2076 } __attribute__ ((__packed__)) INDEX_BLOCK;
 2077 
 2078 typedef INDEX_BLOCK INDEX_ALLOCATION;
 2079 
 2080 /*
 2081  * The system file FILE_Extend/$Reparse contains an index named $R listing
 2082  * all reparse points on the volume. The index entry keys are as defined
 2083  * below. Note, that there is no index data associated with the index entries.
 2084  *
 2085  * The index entries are sorted by the index key file_id. The collation rule is
 2086  * COLLATION_NTOFS_ULONGS. FIXME: Verify whether the reparse_tag is not the
 2087  * primary key / is not a key at all. (AIA)
 2088  */
 2089 typedef struct {
 2090         le32 reparse_tag;       /* Reparse point type (inc. flags). */
 2091         leMFT_REF file_id;      /* Mft record of the file containing the
 2092                                    reparse point attribute. */
 2093 } __attribute__ ((__packed__)) REPARSE_INDEX_KEY;
 2094 
 2095 /*
 2096  * Quota flags (32-bit).
 2097  *
 2098  * The user quota flags.  Names explain meaning.
 2099  */
 2100 enum {
 2101         QUOTA_FLAG_DEFAULT_LIMITS       = cpu_to_le32(0x00000001),
 2102         QUOTA_FLAG_LIMIT_REACHED        = cpu_to_le32(0x00000002),
 2103         QUOTA_FLAG_ID_DELETED           = cpu_to_le32(0x00000004),
 2104 
 2105         QUOTA_FLAG_USER_MASK            = cpu_to_le32(0x00000007),
 2106         /* This is a bit mask for the user quota flags. */
 2107 
 2108         /*
 2109          * These flags are only present in the quota defaults index entry, i.e.
 2110          * in the entry where owner_id = QUOTA_DEFAULTS_ID.
 2111          */
 2112         QUOTA_FLAG_TRACKING_ENABLED     = cpu_to_le32(0x00000010),
 2113         QUOTA_FLAG_ENFORCEMENT_ENABLED  = cpu_to_le32(0x00000020),
 2114         QUOTA_FLAG_TRACKING_REQUESTED   = cpu_to_le32(0x00000040),
 2115         QUOTA_FLAG_LOG_THRESHOLD        = cpu_to_le32(0x00000080),
 2116 
 2117         QUOTA_FLAG_LOG_LIMIT            = cpu_to_le32(0x00000100),
 2118         QUOTA_FLAG_OUT_OF_DATE          = cpu_to_le32(0x00000200),
 2119         QUOTA_FLAG_CORRUPT              = cpu_to_le32(0x00000400),
 2120         QUOTA_FLAG_PENDING_DELETES      = cpu_to_le32(0x00000800),
 2121 };
 2122 
 2123 typedef le32 QUOTA_FLAGS;
 2124 
 2125 /*
 2126  * The system file FILE_Extend/$Quota contains two indexes $O and $Q. Quotas
 2127  * are on a per volume and per user basis.
 2128  *
 2129  * The $Q index contains one entry for each existing user_id on the volume. The
 2130  * index key is the user_id of the user/group owning this quota control entry,
 2131  * i.e. the key is the owner_id. The user_id of the owner of a file, i.e. the
 2132  * owner_id, is found in the standard information attribute. The collation rule
 2133  * for $Q is COLLATION_NTOFS_ULONG.
 2134  *
 2135  * The $O index contains one entry for each user/group who has been assigned
 2136  * a quota on that volume. The index key holds the SID of the user_id the
 2137  * entry belongs to, i.e. the owner_id. The collation rule for $O is
 2138  * COLLATION_NTOFS_SID.
 2139  *
 2140  * The $O index entry data is the user_id of the user corresponding to the SID.
 2141  * This user_id is used as an index into $Q to find the quota control entry
 2142  * associated with the SID.
 2143  *
 2144  * The $Q index entry data is the quota control entry and is defined below.
 2145  */
 2146 typedef struct {
 2147         le32 version;           /* Currently equals 2. */
 2148         QUOTA_FLAGS flags;      /* Flags describing this quota entry. */
 2149         le64 bytes_used;        /* How many bytes of the quota are in use. */
 2150         sle64 change_time;      /* Last time this quota entry was changed. */
 2151         sle64 threshold;        /* Soft quota (-1 if not limited). */
 2152         sle64 limit;            /* Hard quota (-1 if not limited). */
 2153         sle64 exceeded_time;    /* How long the soft quota has been exceeded. */
 2154         SID sid;                /* The SID of the user/object associated with
 2155                                    this quota entry.  Equals zero for the quota
 2156                                    defaults entry (and in fact on a WinXP
 2157                                    volume, it is not present at all). */
 2158 } __attribute__ ((__packed__)) QUOTA_CONTROL_ENTRY;
 2159 
 2160 /*
 2161  * Predefined owner_id values (32-bit).
 2162  */
 2163 enum {
 2164         QUOTA_INVALID_ID        = cpu_to_le32(0x00000000),
 2165         QUOTA_DEFAULTS_ID       = cpu_to_le32(0x00000001),
 2166         QUOTA_FIRST_USER_ID     = cpu_to_le32(0x00000100),
 2167 };
 2168 
 2169 /*
 2170  * Current constants for quota control entries.
 2171  */
 2172 typedef enum {
 2173         /* Current version. */
 2174         QUOTA_VERSION   = 2,
 2175 } QUOTA_CONTROL_ENTRY_CONSTANTS;
 2176 
 2177 /*
 2178  * Index entry flags (16-bit).
 2179  */
 2180 enum {
 2181         INDEX_ENTRY_NODE = cpu_to_le16(1), /* This entry contains a
 2182                         sub-node, i.e. a reference to an index block in form of
 2183                         a virtual cluster number (see below). */
 2184         INDEX_ENTRY_END  = cpu_to_le16(2), /* This signifies the last
 2185                         entry in an index block.  The index entry does not
 2186                         represent a file but it can point to a sub-node. */
 2187 
 2188         INDEX_ENTRY_SPACE_FILLER = cpu_to_le16(0xffff), /* gcc: Force
 2189                         enum bit width to 16-bit. */
 2190 } __attribute__ ((__packed__));
 2191 
 2192 typedef le16 INDEX_ENTRY_FLAGS;
 2193 
 2194 /*
 2195  * This the index entry header (see below).
 2196  */
 2197 typedef struct {
 2198 /*  0*/ union {
 2199                 struct { /* Only valid when INDEX_ENTRY_END is not set. */
 2200                         leMFT_REF indexed_file; /* The mft reference of the file
 2201                                                    described by this index
 2202                                                    entry. Used for directory
 2203                                                    indexes. */
 2204                 } __attribute__ ((__packed__)) dir;
 2205                 struct { /* Used for views/indexes to find the entry's data. */
 2206                         le16 data_offset;       /* Data byte offset from this
 2207                                                    INDEX_ENTRY. Follows the
 2208                                                    index key. */
 2209                         le16 data_length;       /* Data length in bytes. */
 2210                         le32 reservedV;         /* Reserved (zero). */
 2211                 } __attribute__ ((__packed__)) vi;
 2212         } __attribute__ ((__packed__)) data;
 2213 /*  8*/ le16 length;             /* Byte size of this index entry, multiple of
 2214                                     8-bytes. */
 2215 /* 10*/ le16 key_length;         /* Byte size of the key value, which is in the
 2216                                     index entry. It follows field reserved. Not
 2217                                     multiple of 8-bytes. */
 2218 /* 12*/ INDEX_ENTRY_FLAGS flags; /* Bit field of INDEX_ENTRY_* flags. */
 2219 /* 14*/ le16 reserved;           /* Reserved/align to 8-byte boundary. */
 2220 /* sizeof() = 16 bytes */
 2221 } __attribute__ ((__packed__)) INDEX_ENTRY_HEADER;
 2222 
 2223 /*
 2224  * This is an index entry. A sequence of such entries follows each INDEX_HEADER
 2225  * structure. Together they make up a complete index. The index follows either
 2226  * an index root attribute or an index allocation attribute.
 2227  *
 2228  * NOTE: Before NTFS 3.0 only filename attributes were indexed.
 2229  */
 2230 typedef struct {
 2231 /*Ofs*/
 2232 /*  0   INDEX_ENTRY_HEADER; -- Unfolded here as gcc dislikes unnamed structs. */
 2233         union {
 2234                 struct { /* Only valid when INDEX_ENTRY_END is not set. */
 2235                         leMFT_REF indexed_file; /* The mft reference of the file
 2236                                                    described by this index
 2237                                                    entry. Used for directory
 2238                                                    indexes. */
 2239                 } __attribute__ ((__packed__)) dir;
 2240                 struct { /* Used for views/indexes to find the entry's data. */
 2241                         le16 data_offset;       /* Data byte offset from this
 2242                                                    INDEX_ENTRY. Follows the
 2243                                                    index key. */
 2244                         le16 data_length;       /* Data length in bytes. */
 2245                         le32 reservedV;         /* Reserved (zero). */
 2246                 } __attribute__ ((__packed__)) vi;
 2247         } __attribute__ ((__packed__)) data;
 2248         le16 length;             /* Byte size of this index entry, multiple of
 2249                                     8-bytes. */
 2250         le16 key_length;         /* Byte size of the key value, which is in the
 2251                                     index entry. It follows field reserved. Not
 2252                                     multiple of 8-bytes. */
 2253         INDEX_ENTRY_FLAGS flags; /* Bit field of INDEX_ENTRY_* flags. */
 2254         le16 reserved;           /* Reserved/align to 8-byte boundary. */
 2255 
 2256 /* 16*/ union {         /* The key of the indexed attribute. NOTE: Only present
 2257                            if INDEX_ENTRY_END bit in flags is not set. NOTE: On
 2258                            NTFS versions before 3.0 the only valid key is the
 2259                            FILE_NAME_ATTR. On NTFS 3.0+ the following
 2260                            additional index keys are defined: */
 2261                 FILE_NAME_ATTR file_name;/* $I30 index in directories. */
 2262                 SII_INDEX_KEY sii;      /* $SII index in $Secure. */
 2263                 SDH_INDEX_KEY sdh;      /* $SDH index in $Secure. */
 2264                 GUID object_id;         /* $O index in FILE_Extend/$ObjId: The
 2265                                            object_id of the mft record found in
 2266                                            the data part of the index. */
 2267                 REPARSE_INDEX_KEY reparse;      /* $R index in
 2268                                                    FILE_Extend/$Reparse. */
 2269                 SID sid;                /* $O index in FILE_Extend/$Quota:
 2270                                            SID of the owner of the user_id. */
 2271                 le32 owner_id;          /* $Q index in FILE_Extend/$Quota:
 2272                                            user_id of the owner of the quota
 2273                                            control entry in the data part of
 2274                                            the index. */
 2275         } __attribute__ ((__packed__)) key;
 2276         /* The (optional) index data is inserted here when creating. */
 2277         // leVCN vcn;   /* If INDEX_ENTRY_NODE bit in flags is set, the last
 2278         //                 eight bytes of this index entry contain the virtual
 2279         //                 cluster number of the index block that holds the
 2280         //                 entries immediately preceding the current entry (the
 2281         //                 vcn references the corresponding cluster in the data
 2282         //                 of the non-resident index allocation attribute). If
 2283         //                 the key_length is zero, then the vcn immediately
 2284         //                 follows the INDEX_ENTRY_HEADER. Regardless of
 2285         //                 key_length, the address of the 8-byte boundary
 2286         //                 aligned vcn of INDEX_ENTRY{_HEADER} *ie is given by
 2287         //                 (char*)ie + le16_to_cpu(ie*)->length) - sizeof(VCN),
 2288         //                 where sizeof(VCN) can be hardcoded as 8 if wanted. */
 2289 } __attribute__ ((__packed__)) INDEX_ENTRY;
 2290 
 2291 /*
 2292  * Attribute: Bitmap (0xb0).
 2293  *
 2294  * Contains an array of bits (aka a bitfield).
 2295  *
 2296  * When used in conjunction with the index allocation attribute, each bit
 2297  * corresponds to one index block within the index allocation attribute. Thus
 2298  * the number of bits in the bitmap * index block size / cluster size is the
 2299  * number of clusters in the index allocation attribute.
 2300  */
 2301 typedef struct {
 2302         u8 bitmap[0];                   /* Array of bits. */
 2303 } __attribute__ ((__packed__)) BITMAP_ATTR;
 2304 
 2305 /*
 2306  * The reparse point tag defines the type of the reparse point. It also
 2307  * includes several flags, which further describe the reparse point.
 2308  *
 2309  * The reparse point tag is an unsigned 32-bit value divided in three parts:
 2310  *
 2311  * 1. The least significant 16 bits (i.e. bits 0 to 15) specifiy the type of
 2312  *    the reparse point.
 2313  * 2. The 13 bits after this (i.e. bits 16 to 28) are reserved for future use.
 2314  * 3. The most significant three bits are flags describing the reparse point.
 2315  *    They are defined as follows:
 2316  *      bit 29: Name surrogate bit. If set, the filename is an alias for
 2317  *              another object in the system.
 2318  *      bit 30: High-latency bit. If set, accessing the first byte of data will
 2319  *              be slow. (E.g. the data is stored on a tape drive.)
 2320  *      bit 31: Microsoft bit. If set, the tag is owned by Microsoft. User
 2321  *              defined tags have to use zero here.
 2322  *
 2323  * These are the predefined reparse point tags:
 2324  */
 2325 enum {
 2326         IO_REPARSE_TAG_IS_ALIAS         = cpu_to_le32(0x20000000),
 2327         IO_REPARSE_TAG_IS_HIGH_LATENCY  = cpu_to_le32(0x40000000),
 2328         IO_REPARSE_TAG_IS_MICROSOFT     = cpu_to_le32(0x80000000),
 2329 
 2330         IO_REPARSE_TAG_RESERVED_ZERO    = cpu_to_le32(0x00000000),
 2331         IO_REPARSE_TAG_RESERVED_ONE     = cpu_to_le32(0x00000001),
 2332         IO_REPARSE_TAG_RESERVED_RANGE   = cpu_to_le32(0x00000001),
 2333 
 2334         IO_REPARSE_TAG_NSS              = cpu_to_le32(0x68000005),
 2335         IO_REPARSE_TAG_NSS_RECOVER      = cpu_to_le32(0x68000006),
 2336         IO_REPARSE_TAG_SIS              = cpu_to_le32(0x68000007),
 2337         IO_REPARSE_TAG_DFS              = cpu_to_le32(0x68000008),
 2338 
 2339         IO_REPARSE_TAG_MOUNT_POINT      = cpu_to_le32(0x88000003),
 2340 
 2341         IO_REPARSE_TAG_HSM              = cpu_to_le32(0xa8000004),
 2342 
 2343         IO_REPARSE_TAG_SYMBOLIC_LINK    = cpu_to_le32(0xe8000000),
 2344 
 2345         IO_REPARSE_TAG_VALID_VALUES     = cpu_to_le32(0xe000ffff),
 2346 };
 2347 
 2348 /*
 2349  * Attribute: Reparse point (0xc0).
 2350  *
 2351  * NOTE: Can be resident or non-resident.
 2352  */
 2353 typedef struct {
 2354         le32 reparse_tag;               /* Reparse point type (inc. flags). */
 2355         le16 reparse_data_length;       /* Byte size of reparse data. */
 2356         le16 reserved;                  /* Align to 8-byte boundary. */
 2357         u8 reparse_data[0];             /* Meaning depends on reparse_tag. */
 2358 } __attribute__ ((__packed__)) REPARSE_POINT;
 2359 
 2360 /*
 2361  * Attribute: Extended attribute (EA) information (0xd0).
 2362  *
 2363  * NOTE: Always resident. (Is this true???)
 2364  */
 2365 typedef struct {
 2366         le16 ea_length;         /* Byte size of the packed extended
 2367                                    attributes. */
 2368         le16 need_ea_count;     /* The number of extended attributes which have
 2369                                    the NEED_EA bit set. */
 2370         le32 ea_query_length;   /* Byte size of the buffer required to query
 2371                                    the extended attributes when calling
 2372                                    ZwQueryEaFile() in Windows NT/2k. I.e. the
 2373                                    byte size of the unpacked extended
 2374                                    attributes. */
 2375 } __attribute__ ((__packed__)) EA_INFORMATION;
 2376 
 2377 /*
 2378  * Extended attribute flags (8-bit).
 2379  */
 2380 enum {
 2381         NEED_EA = 0x80          /* If set the file to which the EA belongs
 2382                                    cannot be interpreted without understanding
 2383                                    the associates extended attributes. */
 2384 } __attribute__ ((__packed__));
 2385 
 2386 typedef u8 EA_FLAGS;
 2387 
 2388 /*
 2389  * Attribute: Extended attribute (EA) (0xe0).
 2390  *
 2391  * NOTE: Can be resident or non-resident.
 2392  *
 2393  * Like the attribute list and the index buffer list, the EA attribute value is
 2394  * a sequence of EA_ATTR variable length records.
 2395  */
 2396 typedef struct {
 2397         le32 next_entry_offset; /* Offset to the next EA_ATTR. */
 2398         EA_FLAGS flags;         /* Flags describing the EA. */
 2399         u8 ea_name_length;      /* Length of the name of the EA in bytes
 2400                                    excluding the '\0' byte terminator. */
 2401         le16 ea_value_length;   /* Byte size of the EA's value. */
 2402         u8 ea_name[0];          /* Name of the EA.  Note this is ASCII, not
 2403                                    Unicode and it is zero terminated. */
 2404         u8 ea_value[0];         /* The value of the EA.  Immediately follows
 2405                                    the name. */
 2406 } __attribute__ ((__packed__)) EA_ATTR;
 2407 
 2408 /*
 2409  * Attribute: Property set (0xf0).
 2410  *
 2411  * Intended to support Native Structure Storage (NSS) - a feature removed from
 2412  * NTFS 3.0 during beta testing.
 2413  */
 2414 typedef struct {
 2415         /* Irrelevant as feature unused. */
 2416 } __attribute__ ((__packed__)) PROPERTY_SET;
 2417 
 2418 /*
 2419  * Attribute: Logged utility stream (0x100).
 2420  *
 2421  * NOTE: Can be resident or non-resident.
 2422  *
 2423  * Operations on this attribute are logged to the journal ($LogFile) like
 2424  * normal metadata changes.
 2425  *
 2426  * Used by the Encrypting File System (EFS). All encrypted files have this
 2427  * attribute with the name $EFS.
 2428  */
 2429 typedef struct {
 2430         /* Can be anything the creator chooses. */
 2431         /* EFS uses it as follows: */
 2432         // FIXME: Type this info, verifying it along the way. (AIA)
 2433 } __attribute__ ((__packed__)) LOGGED_UTILITY_STREAM, EFS_ATTR;
 2434 
 2435 #endif /* _LINUX_NTFS_LAYOUT_H */

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