xref: /openbmc/linux/fs/ntfs/layout.h (revision e8e0929d)
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 everytime 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 inheritence 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  *	inheritence 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 inheritence 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 inheritence 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 aditional 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  * dircetories 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 	//		   alligned 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 */
2436