1/*
2 * attrib.h - Exports for attribute handling. Originated from the Linux-NTFS project.
3 *
4 * Copyright (c) 2000-2004 Anton Altaparmakov
5 * Copyright (c) 2004-2005 Yura Pakhuchiy
6 * Copyright (c) 2006-2007 Szabolcs Szakacsits
7 * Copyright (c) 2010      Jean-Pierre Andre
8 *
9 * This program/include file is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as published
11 * by the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program/include file is distributed in the hope that it will be
15 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
16 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program (in the main directory of the NTFS-3G
21 * distribution in the file COPYING); if not, write to the Free Software
22 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23 */
24
25#ifndef _NTFS_ATTRIB_H
26#define _NTFS_ATTRIB_H
27
28/* Forward declarations */
29typedef struct _ntfs_attr ntfs_attr;
30typedef struct _ntfs_attr_search_ctx ntfs_attr_search_ctx;
31
32#include "types.h"
33#include "inode.h"
34#include "unistr.h"
35#include "runlist.h"
36#include "volume.h"
37#include "debug.h"
38#include "logging.h"
39
40extern ntfschar AT_UNNAMED[];
41extern ntfschar STREAM_SDS[];
42
43/* The little endian Unicode string $TXF_DATA as a global constant. */
44extern ntfschar TXF_DATA[10];
45
46/**
47 * enum ntfs_lcn_special_values - special return values for ntfs_*_vcn_to_lcn()
48 *
49 * Special return values for ntfs_rl_vcn_to_lcn() and ntfs_attr_vcn_to_lcn().
50 *
51 * TODO: Describe them.
52 */
53typedef enum {
54	LCN_HOLE		= -1,	/* Keep this as highest value or die! */
55	LCN_RL_NOT_MAPPED	= -2,
56	LCN_ENOENT		= -3,
57	LCN_EINVAL		= -4,
58	LCN_EIO			= -5,
59} ntfs_lcn_special_values;
60
61typedef enum {			/* ways of processing holes when expanding */
62	HOLES_NO,
63	HOLES_OK,
64	HOLES_DELAY,
65	HOLES_NONRES
66} hole_type;
67
68/**
69 * struct ntfs_attr_search_ctx - search context used in attribute search functions
70 * @mrec:	buffer containing mft record to search
71 * @attr:	attribute record in @mrec where to begin/continue search
72 * @is_first:	if true lookup_attr() begins search with @attr, else after @attr
73 *
74 * Structure must be initialized to zero before the first call to one of the
75 * attribute search functions. Initialize @mrec to point to the mft record to
76 * search, and @attr to point to the first attribute within @mrec (not necessary
77 * if calling the _first() functions), and set @is_first to TRUE (not necessary
78 * if calling the _first() functions).
79 *
80 * If @is_first is TRUE, the search begins with @attr. If @is_first is FALSE,
81 * the search begins after @attr. This is so that, after the first call to one
82 * of the search attribute functions, we can call the function again, without
83 * any modification of the search context, to automagically get the next
84 * matching attribute.
85 */
86struct _ntfs_attr_search_ctx {
87	MFT_RECORD *mrec;
88	ATTR_RECORD *attr;
89	BOOL is_first;
90	ntfs_inode *ntfs_ino;
91	ATTR_LIST_ENTRY *al_entry;
92	ntfs_inode *base_ntfs_ino;
93	MFT_RECORD *base_mrec;
94	ATTR_RECORD *base_attr;
95};
96
97extern void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx *ctx);
98extern ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(ntfs_inode *ni,
99		MFT_RECORD *mrec);
100extern void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *ctx);
101
102extern int ntfs_attr_lookup(const ATTR_TYPES type, const ntfschar *name,
103		const u32 name_len, const IGNORE_CASE_BOOL ic,
104		const VCN lowest_vcn, const u8 *val, const u32 val_len,
105		ntfs_attr_search_ctx *ctx);
106
107extern int ntfs_attr_position(const ATTR_TYPES type, ntfs_attr_search_ctx *ctx);
108
109extern ATTR_DEF *ntfs_attr_find_in_attrdef(const ntfs_volume *vol,
110		const ATTR_TYPES type);
111
112/**
113 * ntfs_attrs_walk - syntactic sugar for walking all attributes in an inode
114 * @ctx:	initialised attribute search context
115 *
116 * Syntactic sugar for walking attributes in an inode.
117 *
118 * Return 0 on success and -1 on error with errno set to the error code from
119 * ntfs_attr_lookup().
120 *
121 * Example: When you want to enumerate all attributes in an open ntfs inode
122 *	    @ni, you can simply do:
123 *
124 *	int err;
125 *	ntfs_attr_search_ctx *ctx = ntfs_attr_get_search_ctx(ni, NULL);
126 *	if (!ctx)
127 *		// Error code is in errno. Handle this case.
128 *	while (!(err = ntfs_attrs_walk(ctx))) {
129 *		ATTR_RECORD *attr = ctx->attr;
130 *		// attr now contains the next attribute. Do whatever you want
131 *		// with it and then just continue with the while loop.
132 *	}
133 *	if (err && errno != ENOENT)
134 *		// Ooops. An error occurred! You should handle this case.
135 *	// Now finished with all attributes in the inode.
136 */
137static __inline__ int ntfs_attrs_walk(ntfs_attr_search_ctx *ctx)
138{
139	return ntfs_attr_lookup(AT_UNUSED, NULL, 0, CASE_SENSITIVE, 0,
140			NULL, 0, ctx);
141}
142
143/**
144 * struct ntfs_attr - ntfs in memory non-resident attribute structure
145 * @rl:			if not NULL, the decompressed runlist
146 * @ni:			base ntfs inode to which this attribute belongs
147 * @type:		attribute type
148 * @name:		Unicode name of the attribute
149 * @name_len:		length of @name in Unicode characters
150 * @state:		NTFS attribute specific flags describing this attribute
151 * @allocated_size:	copy from the attribute record
152 * @data_size:		copy from the attribute record
153 * @initialized_size:	copy from the attribute record
154 * @compressed_size:	copy from the attribute record
155 * @compression_block_size:		size of a compression block (cb)
156 * @compression_block_size_bits:	log2 of the size of a cb
157 * @compression_block_clusters:		number of clusters per cb
158 *
159 * This structure exists purely to provide a mechanism of caching the runlist
160 * of an attribute. If you want to operate on a particular attribute extent,
161 * you should not be using this structure at all. If you want to work with a
162 * resident attribute, you should not be using this structure at all. As a
163 * fail-safe check make sure to test NAttrNonResident() and if it is false, you
164 * know you shouldn't be using this structure.
165 *
166 * If you want to work on a resident attribute or on a specific attribute
167 * extent, you should use ntfs_lookup_attr() to retrieve the attribute (extent)
168 * record, edit that, and then write back the mft record (or set the
169 * corresponding ntfs inode dirty for delayed write back).
170 *
171 * @rl is the decompressed runlist of the attribute described by this
172 * structure. Obviously this only makes sense if the attribute is not resident,
173 * i.e. NAttrNonResident() is true. If the runlist hasn't been decompressed yet
174 * @rl is NULL, so be prepared to cope with @rl == NULL.
175 *
176 * @ni is the base ntfs inode of the attribute described by this structure.
177 *
178 * @type is the attribute type (see layout.h for the definition of ATTR_TYPES),
179 * @name and @name_len are the little endian Unicode name and the name length
180 * in Unicode characters of the attribute, respectively.
181 *
182 * @state contains NTFS attribute specific flags describing this attribute
183 * structure. See ntfs_attr_state_bits above.
184 */
185struct _ntfs_attr {
186	runlist_element *rl;
187	ntfs_inode *ni;
188	ATTR_TYPES type;
189	ATTR_FLAGS data_flags;
190	ntfschar *name;
191	u32 name_len;
192	unsigned long state;
193	s64 allocated_size;
194	s64 data_size;
195	s64 initialized_size;
196	s64 compressed_size;
197	u32 compression_block_size;
198	u8 compression_block_size_bits;
199	u8 compression_block_clusters;
200	s8 unused_runs; /* pre-reserved entries available */
201};
202
203/**
204 * enum ntfs_attr_state_bits - bits for the state field in the ntfs_attr
205 * structure
206 */
207typedef enum {
208	NA_Initialized,		/* 1: structure is initialized. */
209	NA_NonResident,		/* 1: Attribute is not resident. */
210	NA_BeingNonResident,	/* 1: Attribute is being made not resident. */
211	NA_FullyMapped,		/* 1: Attribute has been fully mapped */
212	NA_DataAppending,	/* 1: Attribute is being appended to */
213	NA_ComprClosing,	/* 1: Compressed attribute is being closed */
214	NA_RunlistDirty,	/* 1: Runlist has been updated */
215} ntfs_attr_state_bits;
216
217#define  test_nattr_flag(na, flag)	 test_bit(NA_##flag, (na)->state)
218#define   set_nattr_flag(na, flag)	  set_bit(NA_##flag, (na)->state)
219#define clear_nattr_flag(na, flag)	clear_bit(NA_##flag, (na)->state)
220
221#define NAttrInitialized(na)		 test_nattr_flag(na, Initialized)
222#define NAttrSetInitialized(na)		  set_nattr_flag(na, Initialized)
223#define NAttrClearInitialized(na)	clear_nattr_flag(na, Initialized)
224
225#define NAttrNonResident(na)		 test_nattr_flag(na, NonResident)
226#define NAttrSetNonResident(na)		  set_nattr_flag(na, NonResident)
227#define NAttrClearNonResident(na)	clear_nattr_flag(na, NonResident)
228
229#define NAttrBeingNonResident(na)	test_nattr_flag(na, BeingNonResident)
230#define NAttrSetBeingNonResident(na)	set_nattr_flag(na, BeingNonResident)
231#define NAttrClearBeingNonResident(na)	clear_nattr_flag(na, BeingNonResident)
232
233#define NAttrFullyMapped(na)		test_nattr_flag(na, FullyMapped)
234#define NAttrSetFullyMapped(na)		set_nattr_flag(na, FullyMapped)
235#define NAttrClearFullyMapped(na)	clear_nattr_flag(na, FullyMapped)
236
237#define NAttrDataAppending(na)		test_nattr_flag(na, DataAppending)
238#define NAttrSetDataAppending(na)	set_nattr_flag(na, DataAppending)
239#define NAttrClearDataAppending(na)	clear_nattr_flag(na, DataAppending)
240
241#define NAttrRunlistDirty(na)		test_nattr_flag(na, RunlistDirty)
242#define NAttrSetRunlistDirty(na)	set_nattr_flag(na, RunlistDirty)
243#define NAttrClearRunlistDirty(na)	clear_nattr_flag(na, RunlistDirty)
244
245#define NAttrComprClosing(na)		test_nattr_flag(na, ComprClosing)
246#define NAttrSetComprClosing(na)	set_nattr_flag(na, ComprClosing)
247#define NAttrClearComprClosing(na)	clear_nattr_flag(na, ComprClosing)
248
249#define GenNAttrIno(func_name, flag)			\
250extern int NAttr##func_name(ntfs_attr *na);		\
251extern void NAttrSet##func_name(ntfs_attr *na);		\
252extern void NAttrClear##func_name(ntfs_attr *na);
253
254GenNAttrIno(Compressed, FILE_ATTR_COMPRESSED)
255GenNAttrIno(Encrypted, 	FILE_ATTR_ENCRYPTED)
256GenNAttrIno(Sparse, 	FILE_ATTR_SPARSE_FILE)
257#undef GenNAttrIno
258
259/**
260 * union attr_val - Union of all known attribute values
261 *
262 * For convenience. Used in the attr structure.
263 */
264typedef union {
265	u8 _default;	/* Unnamed u8 to serve as default when just using
266			   a_val without specifying any of the below. */
267	STANDARD_INFORMATION std_inf;
268	ATTR_LIST_ENTRY al_entry;
269	FILE_NAME_ATTR filename;
270	OBJECT_ID_ATTR obj_id;
271	SECURITY_DESCRIPTOR_ATTR sec_desc;
272	VOLUME_NAME vol_name;
273	VOLUME_INFORMATION vol_inf;
274	DATA_ATTR data;
275	INDEX_ROOT index_root;
276	INDEX_BLOCK index_blk;
277	BITMAP_ATTR bmp;
278	REPARSE_POINT reparse;
279	EA_INFORMATION ea_inf;
280	EA_ATTR ea;
281	PROPERTY_SET property_set;
282	LOGGED_UTILITY_STREAM logged_util_stream;
283	EFS_ATTR_HEADER efs;
284} attr_val;
285
286extern void ntfs_attr_init(ntfs_attr *na, const BOOL non_resident,
287		const ATTR_FLAGS data_flags, const BOOL encrypted,
288		const BOOL sparse,
289		const s64 allocated_size, const s64 data_size,
290		const s64 initialized_size, const s64 compressed_size,
291		const u8 compression_unit);
292
293	/* warning : in the following "name" has to be freeable */
294	/* or one of constants AT_UNNAMED, NTFS_INDEX_I30 or STREAM_SDS */
295extern ntfs_attr *ntfs_attr_open(ntfs_inode *ni, const ATTR_TYPES type,
296		ntfschar *name, u32 name_len);
297extern void ntfs_attr_close(ntfs_attr *na);
298
299extern s64 ntfs_attr_pread(ntfs_attr *na, const s64 pos, s64 count,
300		void *b);
301extern s64 ntfs_attr_pwrite(ntfs_attr *na, const s64 pos, s64 count,
302		const void *b);
303extern int ntfs_attr_pclose(ntfs_attr *na);
304
305extern void *ntfs_attr_readall(ntfs_inode *ni, const ATTR_TYPES type,
306			       ntfschar *name, u32 name_len, s64 *data_size);
307
308extern s64 ntfs_attr_mst_pread(ntfs_attr *na, const s64 pos,
309		const s64 bk_cnt, const u32 bk_size, void *dst);
310extern s64 ntfs_attr_mst_pwrite(ntfs_attr *na, const s64 pos,
311		s64 bk_cnt, const u32 bk_size, void *src);
312
313extern int ntfs_attr_map_runlist(ntfs_attr *na, VCN vcn);
314extern int ntfs_attr_map_whole_runlist(ntfs_attr *na);
315
316extern LCN ntfs_attr_vcn_to_lcn(ntfs_attr *na, const VCN vcn);
317extern runlist_element *ntfs_attr_find_vcn(ntfs_attr *na, const VCN vcn);
318
319extern int ntfs_attr_size_bounds_check(const ntfs_volume *vol,
320		const ATTR_TYPES type, const s64 size);
321extern int ntfs_attr_can_be_resident(const ntfs_volume *vol,
322		const ATTR_TYPES type);
323int ntfs_attr_make_non_resident(ntfs_attr *na,
324		ntfs_attr_search_ctx *ctx);
325int ntfs_attr_force_non_resident(ntfs_attr *na);
326extern int ntfs_make_room_for_attr(MFT_RECORD *m, u8 *pos, u32 size);
327
328extern int ntfs_resident_attr_record_add(ntfs_inode *ni, ATTR_TYPES type,
329		const ntfschar *name, u8 name_len, const u8 *val, u32 size,
330		ATTR_FLAGS flags);
331extern int ntfs_non_resident_attr_record_add(ntfs_inode *ni, ATTR_TYPES type,
332		const ntfschar *name, u8 name_len, VCN lowest_vcn,
333		int dataruns_size, ATTR_FLAGS flags);
334extern int ntfs_attr_record_rm(ntfs_attr_search_ctx *ctx);
335
336extern int ntfs_attr_add(ntfs_inode *ni, ATTR_TYPES type,
337		ntfschar *name, u8 name_len, const u8 *val, s64 size);
338extern int ntfs_attr_set_flags(ntfs_inode *ni, ATTR_TYPES type,
339		const ntfschar *name, u8 name_len, ATTR_FLAGS flags,
340		ATTR_FLAGS mask);
341extern int ntfs_attr_rm(ntfs_attr *na);
342
343extern int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size);
344
345extern int ntfs_resident_attr_value_resize(MFT_RECORD *m, ATTR_RECORD *a,
346		const u32 new_size);
347
348extern int ntfs_attr_record_move_to(ntfs_attr_search_ctx *ctx, ntfs_inode *ni);
349extern int ntfs_attr_record_move_away(ntfs_attr_search_ctx *ctx, int extra);
350
351extern int ntfs_attr_update_mapping_pairs(ntfs_attr *na, VCN from_vcn);
352
353extern int ntfs_attr_truncate(ntfs_attr *na, const s64 newsize);
354extern int ntfs_attr_truncate_solid(ntfs_attr *na, const s64 newsize);
355
356/**
357 * get_attribute_value_length - return the length of the value of an attribute
358 * @a:	pointer to a buffer containing the attribute record
359 *
360 * Return the byte size of the attribute value of the attribute @a (as it
361 * would be after eventual decompression and filling in of holes if sparse).
362 * If we return 0, check errno. If errno is 0 the actual length was 0,
363 * otherwise errno describes the error.
364 *
365 * FIXME: Describe possible errnos.
366 */
367extern s64 ntfs_get_attribute_value_length(const ATTR_RECORD *a);
368
369/**
370 * get_attribute_value - return the attribute value of an attribute
371 * @vol:	volume on which the attribute is present
372 * @a:		attribute to get the value of
373 * @b:		destination buffer for the attribute value
374 *
375 * Make a copy of the attribute value of the attribute @a into the destination
376 * buffer @b. Note, that the size of @b has to be at least equal to the value
377 * returned by get_attribute_value_length(@a).
378 *
379 * Return number of bytes copied. If this is zero check errno. If errno is 0
380 * then nothing was read due to a zero-length attribute value, otherwise
381 * errno describes the error.
382 */
383extern s64 ntfs_get_attribute_value(const ntfs_volume *vol,
384				    const ATTR_RECORD *a, u8 *b);
385
386extern void  ntfs_attr_name_free(char **name);
387extern char *ntfs_attr_name_get(const ntfschar *uname, const int uname_len);
388extern int   ntfs_attr_exist(ntfs_inode *ni, const ATTR_TYPES type,
389		const ntfschar *name, u32 name_len);
390extern int   ntfs_attr_remove(ntfs_inode *ni, const ATTR_TYPES type,
391			      ntfschar *name, u32 name_len);
392extern s64   ntfs_attr_get_free_bits(ntfs_attr *na);
393extern int ntfs_attr_data_read(ntfs_inode *ni,
394		ntfschar *stream_name, int stream_name_len,
395		char *buf, size_t size, off_t offset);
396extern int ntfs_attr_data_write(ntfs_inode *ni,
397		ntfschar *stream_name, int stream_name_len,
398		const char *buf, size_t size, off_t offset);
399extern int ntfs_attr_shrink_size(ntfs_inode *ni, ntfschar *stream_name,
400		int stream_name_len, off_t offset);
401extern int ntfs_attr_inconsistent(const ATTR_RECORD *a, const MFT_REF mref);
402
403#endif /* defined _NTFS_ATTRIB_H */
404
405