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 * 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 NTFS-3G 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 _NTFS_ATTRIB_H 25 #define _NTFS_ATTRIB_H 26 27 /* Forward declarations */ 28 typedef struct _ntfs_attr ntfs_attr; 29 typedef struct _ntfs_attr_search_ctx ntfs_attr_search_ctx; 30 31 #include "types.h" 32 #include "inode.h" 33 #include "unistr.h" 34 #include "runlist.h" 35 #include "volume.h" 36 #include "debug.h" 37 #include "logging.h" 38 39 extern ntfschar AT_UNNAMED[]; 40 41 /** 42 * enum ntfs_lcn_special_values - special return values for ntfs_*_vcn_to_lcn() 43 * 44 * Special return values for ntfs_rl_vcn_to_lcn() and ntfs_attr_vcn_to_lcn(). 45 * 46 * TODO: Describe them. 47 */ 48 typedef enum { 49 LCN_HOLE = -1, /* Keep this as highest value or die! */ 50 LCN_RL_NOT_MAPPED = -2, 51 LCN_ENOENT = -3, 52 LCN_EINVAL = -4, 53 LCN_EIO = -5, 54 } ntfs_lcn_special_values; 55 56 /** 57 * struct ntfs_attr_search_ctx - search context used in attribute search functions 58 * @mrec: buffer containing mft record to search 59 * @attr: attribute record in @mrec where to begin/continue search 60 * @is_first: if true lookup_attr() begins search with @attr, else after @attr 61 * 62 * Structure must be initialized to zero before the first call to one of the 63 * attribute search functions. Initialize @mrec to point to the mft record to 64 * search, and @attr to point to the first attribute within @mrec (not necessary 65 * if calling the _first() functions), and set @is_first to TRUE (not necessary 66 * if calling the _first() functions). 67 * 68 * If @is_first is TRUE, the search begins with @attr. If @is_first is FALSE, 69 * the search begins after @attr. This is so that, after the first call to one 70 * of the search attribute functions, we can call the function again, without 71 * any modification of the search context, to automagically get the next 72 * matching attribute. 73 */ 74 struct _ntfs_attr_search_ctx { 75 MFT_RECORD *mrec; 76 ATTR_RECORD *attr; 77 BOOL is_first; 78 ntfs_inode *ntfs_ino; 79 ATTR_LIST_ENTRY *al_entry; 80 ntfs_inode *base_ntfs_ino; 81 MFT_RECORD *base_mrec; 82 ATTR_RECORD *base_attr; 83 }; 84 85 extern void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx *ctx); 86 extern ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(ntfs_inode *ni, 87 MFT_RECORD *mrec); 88 extern void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *ctx); 89 90 extern int ntfs_attr_lookup(const ATTR_TYPES type, const ntfschar *name, 91 const u32 name_len, const IGNORE_CASE_BOOL ic, 92 const VCN lowest_vcn, const u8 *val, const u32 val_len, 93 ntfs_attr_search_ctx *ctx); 94 95 extern int ntfs_attr_position(const ATTR_TYPES type, ntfs_attr_search_ctx *ctx); 96 97 extern ATTR_DEF *ntfs_attr_find_in_attrdef(const ntfs_volume *vol, 98 const ATTR_TYPES type); 99 100 /** 101 * ntfs_attrs_walk - syntactic sugar for walking all attributes in an inode 102 * @ctx: initialised attribute search context 103 * 104 * Syntactic sugar for walking attributes in an inode. 105 * 106 * Return 0 on success and -1 on error with errno set to the error code from 107 * ntfs_attr_lookup(). 108 * 109 * Example: When you want to enumerate all attributes in an open ntfs inode 110 * @ni, you can simply do: 111 * 112 * int err; 113 * ntfs_attr_search_ctx *ctx = ntfs_attr_get_search_ctx(ni, NULL); 114 * if (!ctx) 115 * // Error code is in errno. Handle this case. 116 * while (!(err = ntfs_attrs_walk(ctx))) { 117 * ATTR_RECORD *attr = ctx->attr; 118 * // attr now contains the next attribute. Do whatever you want 119 * // with it and then just continue with the while loop. 120 * } 121 * if (err && errno != ENOENT) 122 * // Ooops. An error occurred! You should handle this case. 123 * // Now finished with all attributes in the inode. 124 */ 125 static __inline__ int ntfs_attrs_walk(ntfs_attr_search_ctx *ctx) 126 { 127 return ntfs_attr_lookup(AT_UNUSED, NULL, 0, CASE_SENSITIVE, 0, 128 NULL, 0, ctx); 129 } 130 131 /** 132 * struct ntfs_attr - ntfs in memory non-resident attribute structure 133 * @rl: if not NULL, the decompressed runlist 134 * @ni: base ntfs inode to which this attribute belongs 135 * @type: attribute type 136 * @name: Unicode name of the attribute 137 * @name_len: length of @name in Unicode characters 138 * @state: NTFS attribute specific flags describing this attribute 139 * @allocated_size: copy from the attribute record 140 * @data_size: copy from the attribute record 141 * @initialized_size: copy from the attribute record 142 * @compressed_size: copy from the attribute record 143 * @compression_block_size: size of a compression block (cb) 144 * @compression_block_size_bits: log2 of the size of a cb 145 * @compression_block_clusters: number of clusters per cb 146 * 147 * This structure exists purely to provide a mechanism of caching the runlist 148 * of an attribute. If you want to operate on a particular attribute extent, 149 * you should not be using this structure at all. If you want to work with a 150 * resident attribute, you should not be using this structure at all. As a 151 * fail-safe check make sure to test NAttrNonResident() and if it is false, you 152 * know you shouldn't be using this structure. 153 * 154 * If you want to work on a resident attribute or on a specific attribute 155 * extent, you should use ntfs_lookup_attr() to retrieve the attribute (extent) 156 * record, edit that, and then write back the mft record (or set the 157 * corresponding ntfs inode dirty for delayed write back). 158 * 159 * @rl is the decompressed runlist of the attribute described by this 160 * structure. Obviously this only makes sense if the attribute is not resident, 161 * i.e. NAttrNonResident() is true. If the runlist hasn't been decompressed yet 162 * @rl is NULL, so be prepared to cope with @rl == NULL. 163 * 164 * @ni is the base ntfs inode of the attribute described by this structure. 165 * 166 * @type is the attribute type (see layout.h for the definition of ATTR_TYPES), 167 * @name and @name_len are the little endian Unicode name and the name length 168 * in Unicode characters of the attribute, respectively. 169 * 170 * @state contains NTFS attribute specific flags describing this attribute 171 * structure. See ntfs_attr_state_bits above. 172 */ 173 struct _ntfs_attr { 174 runlist_element *rl; 175 ntfs_inode *ni; 176 ATTR_TYPES type; 177 ntfschar *name; 178 u32 name_len; 179 unsigned long state; 180 s64 allocated_size; 181 s64 data_size; 182 s64 initialized_size; 183 s64 compressed_size; 184 u32 compression_block_size; 185 u8 compression_block_size_bits; 186 u8 compression_block_clusters; 187 }; 188 189 /** 190 * enum ntfs_attr_state_bits - bits for the state field in the ntfs_attr 191 * structure 192 */ 193 typedef enum { 194 NA_Initialized, /* 1: structure is initialized. */ 195 NA_NonResident, /* 1: Attribute is not resident. */ 196 } ntfs_attr_state_bits; 197 198 #define test_nattr_flag(na, flag) test_bit(NA_##flag, (na)->state) 199 #define set_nattr_flag(na, flag) set_bit(NA_##flag, (na)->state) 200 #define clear_nattr_flag(na, flag) clear_bit(NA_##flag, (na)->state) 201 202 #define NAttrInitialized(na) test_nattr_flag(na, Initialized) 203 #define NAttrSetInitialized(na) set_nattr_flag(na, Initialized) 204 #define NAttrClearInitialized(na) clear_nattr_flag(na, Initialized) 205 206 #define NAttrNonResident(na) test_nattr_flag(na, NonResident) 207 #define NAttrSetNonResident(na) set_nattr_flag(na, NonResident) 208 #define NAttrClearNonResident(na) clear_nattr_flag(na, NonResident) 209 210 #define GenNAttrIno(func_name, flag) \ 211 extern int NAttr##func_name(ntfs_attr *na); \ 212 extern void NAttrSet##func_name(ntfs_attr *na); \ 213 extern void NAttrClear##func_name(ntfs_attr *na); 214 215 GenNAttrIno(Compressed, FILE_ATTR_COMPRESSED) 216 GenNAttrIno(Encrypted, FILE_ATTR_ENCRYPTED) 217 GenNAttrIno(Sparse, FILE_ATTR_SPARSE_FILE) 218 #undef GenNAttrIno 219 220 /** 221 * union attr_val - Union of all known attribute values 222 * 223 * For convenience. Used in the attr structure. 224 */ 225 typedef union { 226 u8 _default; /* Unnamed u8 to serve as default when just using 227 a_val without specifying any of the below. */ 228 STANDARD_INFORMATION std_inf; 229 ATTR_LIST_ENTRY al_entry; 230 FILE_NAME_ATTR filename; 231 OBJECT_ID_ATTR obj_id; 232 SECURITY_DESCRIPTOR_ATTR sec_desc; 233 VOLUME_NAME vol_name; 234 VOLUME_INFORMATION vol_inf; 235 DATA_ATTR data; 236 INDEX_ROOT index_root; 237 INDEX_BLOCK index_blk; 238 BITMAP_ATTR bmp; 239 REPARSE_POINT reparse; 240 EA_INFORMATION ea_inf; 241 EA_ATTR ea; 242 PROPERTY_SET property_set; 243 LOGGED_UTILITY_STREAM logged_util_stream; 244 EFS_ATTR_HEADER efs; 245 } attr_val; 246 247 extern void ntfs_attr_init(ntfs_attr *na, const BOOL non_resident, 248 const BOOL compressed, const BOOL encrypted, const BOOL sparse, 249 const s64 allocated_size, const s64 data_size, 250 const s64 initialized_size, const s64 compressed_size, 251 const u8 compression_unit); 252 253 extern ntfs_attr *ntfs_attr_open(ntfs_inode *ni, const ATTR_TYPES type, 254 ntfschar *name, u32 name_len); 255 extern void ntfs_attr_close(ntfs_attr *na); 256 257 extern s64 ntfs_attr_pread(ntfs_attr *na, const s64 pos, s64 count, 258 void *b); 259 extern s64 ntfs_attr_pwrite(ntfs_attr *na, const s64 pos, s64 count, 260 const void *b); 261 262 extern void *ntfs_attr_readall(ntfs_inode *ni, const ATTR_TYPES type, 263 ntfschar *name, u32 name_len, s64 *data_size); 264 265 extern s64 ntfs_attr_mst_pread(ntfs_attr *na, const s64 pos, 266 const s64 bk_cnt, const u32 bk_size, void *dst); 267 extern s64 ntfs_attr_mst_pwrite(ntfs_attr *na, const s64 pos, 268 s64 bk_cnt, const u32 bk_size, void *src); 269 270 extern int ntfs_attr_map_runlist(ntfs_attr *na, VCN vcn); 271 extern int ntfs_attr_map_whole_runlist(ntfs_attr *na); 272 273 extern LCN ntfs_attr_vcn_to_lcn(ntfs_attr *na, const VCN vcn); 274 extern runlist_element *ntfs_attr_find_vcn(ntfs_attr *na, const VCN vcn); 275 276 extern int ntfs_attr_size_bounds_check(const ntfs_volume *vol, 277 const ATTR_TYPES type, const s64 size); 278 extern int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, 279 const ATTR_TYPES type); 280 extern int ntfs_attr_can_be_resident(const ntfs_volume *vol, 281 const ATTR_TYPES type); 282 283 extern int ntfs_make_room_for_attr(MFT_RECORD *m, u8 *pos, u32 size); 284 285 extern int ntfs_resident_attr_record_add(ntfs_inode *ni, ATTR_TYPES type, 286 ntfschar *name, u8 name_len, u8 *val, u32 size, 287 ATTR_FLAGS flags); 288 extern int ntfs_non_resident_attr_record_add(ntfs_inode *ni, ATTR_TYPES type, 289 ntfschar *name, u8 name_len, VCN lowest_vcn, int dataruns_size, 290 ATTR_FLAGS flags); 291 extern int ntfs_attr_record_rm(ntfs_attr_search_ctx *ctx); 292 293 extern int ntfs_attr_add(ntfs_inode *ni, ATTR_TYPES type, 294 ntfschar *name, u8 name_len, u8 *val, s64 size); 295 extern int ntfs_attr_rm(ntfs_attr *na); 296 297 extern int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size); 298 299 extern int ntfs_resident_attr_value_resize(MFT_RECORD *m, ATTR_RECORD *a, 300 const u32 new_size); 301 302 extern int ntfs_attr_record_move_to(ntfs_attr_search_ctx *ctx, ntfs_inode *ni); 303 extern int ntfs_attr_record_move_away(ntfs_attr_search_ctx *ctx, int extra); 304 305 extern int ntfs_attr_update_mapping_pairs(ntfs_attr *na, VCN from_vcn); 306 307 extern int ntfs_attr_truncate(ntfs_attr *na, const s64 newsize); 308 309 /** 310 * get_attribute_value_length - return the length of the value of an attribute 311 * @a: pointer to a buffer containing the attribute record 312 * 313 * Return the byte size of the attribute value of the attribute @a (as it 314 * would be after eventual decompression and filling in of holes if sparse). 315 * If we return 0, check errno. If errno is 0 the actual length was 0, 316 * otherwise errno describes the error. 317 * 318 * FIXME: Describe possible errnos. 319 */ 320 extern s64 ntfs_get_attribute_value_length(const ATTR_RECORD *a); 321 322 /** 323 * get_attribute_value - return the attribute value of an attribute 324 * @vol: volume on which the attribute is present 325 * @a: attribute to get the value of 326 * @b: destination buffer for the attribute value 327 * 328 * Make a copy of the attribute value of the attribute @a into the destination 329 * buffer @b. Note, that the size of @b has to be at least equal to the value 330 * returned by get_attribute_value_length(@a). 331 * 332 * Return number of bytes copied. If this is zero check errno. If errno is 0 333 * then nothing was read due to a zero-length attribute value, otherwise 334 * errno describes the error. 335 */ 336 extern s64 ntfs_get_attribute_value(const ntfs_volume *vol, 337 const ATTR_RECORD *a, u8 *b); 338 339 extern void ntfs_attr_name_free(char **name); 340 extern char *ntfs_attr_name_get(const ntfschar *uname, const int uname_len); 341 extern int ntfs_attr_exist(ntfs_inode *ni, const ATTR_TYPES type, 342 ntfschar *name, u32 name_len); 343 extern int ntfs_attr_remove(ntfs_inode *ni, const ATTR_TYPES type, 344 ntfschar *name, u32 name_len); 345 extern s64 ntfs_attr_get_free_bits(ntfs_attr *na); 346 347 #endif /* defined _NTFS_ATTRIB_H */ 348 349