1 /* 2 * unistr.c - NTFS Unicode string handling. Part of the Linux-NTFS project. 3 * 4 * Copyright (c) 2001-2005 Anton Altaparmakov 5 * 6 * This program/include file is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as published 8 * by the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program/include file is distributed in the hope that it will be 12 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program (in the main directory of the Linux-NTFS 18 * distribution in the file COPYING); if not, write to the Free Software 19 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22 #include "types.h" 23 #include "debug.h" 24 #include "ntfs.h" 25 26 /* 27 * IMPORTANT 28 * ========= 29 * 30 * All these routines assume that the Unicode characters are in little endian 31 * encoding inside the strings!!! 32 */ 33 34 /* 35 * This is used by the name collation functions to quickly determine what 36 * characters are (in)valid. 37 */ 38 static const u8 legal_ansi_char_array[0x40] = { 39 0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 40 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 41 42 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 43 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 44 45 0x17, 0x07, 0x18, 0x17, 0x17, 0x17, 0x17, 0x17, 46 0x17, 0x17, 0x18, 0x16, 0x16, 0x17, 0x07, 0x00, 47 48 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 49 0x17, 0x17, 0x04, 0x16, 0x18, 0x16, 0x18, 0x18, 50 }; 51 52 /** 53 * ntfs_are_names_equal - compare two Unicode names for equality 54 * @s1: name to compare to @s2 55 * @s1_len: length in Unicode characters of @s1 56 * @s2: name to compare to @s1 57 * @s2_len: length in Unicode characters of @s2 58 * @ic: ignore case bool 59 * @upcase: upcase table (only if @ic == IGNORE_CASE) 60 * @upcase_size: length in Unicode characters of @upcase (if present) 61 * 62 * Compare the names @s1 and @s2 and return TRUE (1) if the names are 63 * identical, or FALSE (0) if they are not identical. If @ic is IGNORE_CASE, 64 * the @upcase table is used to performa a case insensitive comparison. 65 */ 66 BOOL ntfs_are_names_equal(const ntfschar *s1, size_t s1_len, 67 const ntfschar *s2, size_t s2_len, const IGNORE_CASE_BOOL ic, 68 const ntfschar *upcase, const u32 upcase_size) 69 { 70 if (s1_len != s2_len) 71 return FALSE; 72 if (ic == CASE_SENSITIVE) 73 return !ntfs_ucsncmp(s1, s2, s1_len); 74 return !ntfs_ucsncasecmp(s1, s2, s1_len, upcase, upcase_size); 75 } 76 77 /** 78 * ntfs_collate_names - collate two Unicode names 79 * @name1: first Unicode name to compare 80 * @name2: second Unicode name to compare 81 * @err_val: if @name1 contains an invalid character return this value 82 * @ic: either CASE_SENSITIVE or IGNORE_CASE 83 * @upcase: upcase table (ignored if @ic is CASE_SENSITIVE) 84 * @upcase_len: upcase table size (ignored if @ic is CASE_SENSITIVE) 85 * 86 * ntfs_collate_names collates two Unicode names and returns: 87 * 88 * -1 if the first name collates before the second one, 89 * 0 if the names match, 90 * 1 if the second name collates before the first one, or 91 * @err_val if an invalid character is found in @name1 during the comparison. 92 * 93 * The following characters are considered invalid: '"', '*', '<', '>' and '?'. 94 */ 95 int ntfs_collate_names(const ntfschar *name1, const u32 name1_len, 96 const ntfschar *name2, const u32 name2_len, 97 const int err_val, const IGNORE_CASE_BOOL ic, 98 const ntfschar *upcase, const u32 upcase_len) 99 { 100 u32 cnt, min_len; 101 u16 c1, c2; 102 103 min_len = name1_len; 104 if (name1_len > name2_len) 105 min_len = name2_len; 106 for (cnt = 0; cnt < min_len; ++cnt) { 107 c1 = le16_to_cpu(*name1++); 108 c2 = le16_to_cpu(*name2++); 109 if (ic) { 110 if (c1 < upcase_len) 111 c1 = le16_to_cpu(upcase[c1]); 112 if (c2 < upcase_len) 113 c2 = le16_to_cpu(upcase[c2]); 114 } 115 if (c1 < 64 && legal_ansi_char_array[c1] & 8) 116 return err_val; 117 if (c1 < c2) 118 return -1; 119 if (c1 > c2) 120 return 1; 121 } 122 if (name1_len < name2_len) 123 return -1; 124 if (name1_len == name2_len) 125 return 0; 126 /* name1_len > name2_len */ 127 c1 = le16_to_cpu(*name1); 128 if (c1 < 64 && legal_ansi_char_array[c1] & 8) 129 return err_val; 130 return 1; 131 } 132 133 /** 134 * ntfs_ucsncmp - compare two little endian Unicode strings 135 * @s1: first string 136 * @s2: second string 137 * @n: maximum unicode characters to compare 138 * 139 * Compare the first @n characters of the Unicode strings @s1 and @s2, 140 * The strings in little endian format and appropriate le16_to_cpu() 141 * conversion is performed on non-little endian machines. 142 * 143 * The function returns an integer less than, equal to, or greater than zero 144 * if @s1 (or the first @n Unicode characters thereof) is found, respectively, 145 * to be less than, to match, or be greater than @s2. 146 */ 147 int ntfs_ucsncmp(const ntfschar *s1, const ntfschar *s2, size_t n) 148 { 149 u16 c1, c2; 150 size_t i; 151 152 for (i = 0; i < n; ++i) { 153 c1 = le16_to_cpu(s1[i]); 154 c2 = le16_to_cpu(s2[i]); 155 if (c1 < c2) 156 return -1; 157 if (c1 > c2) 158 return 1; 159 if (!c1) 160 break; 161 } 162 return 0; 163 } 164 165 /** 166 * ntfs_ucsncasecmp - compare two little endian Unicode strings, ignoring case 167 * @s1: first string 168 * @s2: second string 169 * @n: maximum unicode characters to compare 170 * @upcase: upcase table 171 * @upcase_size: upcase table size in Unicode characters 172 * 173 * Compare the first @n characters of the Unicode strings @s1 and @s2, 174 * ignoring case. The strings in little endian format and appropriate 175 * le16_to_cpu() conversion is performed on non-little endian machines. 176 * 177 * Each character is uppercased using the @upcase table before the comparison. 178 * 179 * The function returns an integer less than, equal to, or greater than zero 180 * if @s1 (or the first @n Unicode characters thereof) is found, respectively, 181 * to be less than, to match, or be greater than @s2. 182 */ 183 int ntfs_ucsncasecmp(const ntfschar *s1, const ntfschar *s2, size_t n, 184 const ntfschar *upcase, const u32 upcase_size) 185 { 186 size_t i; 187 u16 c1, c2; 188 189 for (i = 0; i < n; ++i) { 190 if ((c1 = le16_to_cpu(s1[i])) < upcase_size) 191 c1 = le16_to_cpu(upcase[c1]); 192 if ((c2 = le16_to_cpu(s2[i])) < upcase_size) 193 c2 = le16_to_cpu(upcase[c2]); 194 if (c1 < c2) 195 return -1; 196 if (c1 > c2) 197 return 1; 198 if (!c1) 199 break; 200 } 201 return 0; 202 } 203 204 void ntfs_upcase_name(ntfschar *name, u32 name_len, const ntfschar *upcase, 205 const u32 upcase_len) 206 { 207 u32 i; 208 u16 u; 209 210 for (i = 0; i < name_len; i++) 211 if ((u = le16_to_cpu(name[i])) < upcase_len) 212 name[i] = upcase[u]; 213 } 214 215 void ntfs_file_upcase_value(FILE_NAME_ATTR *file_name_attr, 216 const ntfschar *upcase, const u32 upcase_len) 217 { 218 ntfs_upcase_name((ntfschar*)&file_name_attr->file_name, 219 file_name_attr->file_name_length, upcase, upcase_len); 220 } 221 222 int ntfs_file_compare_values(FILE_NAME_ATTR *file_name_attr1, 223 FILE_NAME_ATTR *file_name_attr2, 224 const int err_val, const IGNORE_CASE_BOOL ic, 225 const ntfschar *upcase, const u32 upcase_len) 226 { 227 return ntfs_collate_names((ntfschar*)&file_name_attr1->file_name, 228 file_name_attr1->file_name_length, 229 (ntfschar*)&file_name_attr2->file_name, 230 file_name_attr2->file_name_length, 231 err_val, ic, upcase, upcase_len); 232 } 233 234 /** 235 * ntfs_nlstoucs - convert NLS string to little endian Unicode string 236 * @vol: ntfs volume which we are working with 237 * @ins: input NLS string buffer 238 * @ins_len: length of input string in bytes 239 * @outs: on return contains the allocated output Unicode string buffer 240 * 241 * Convert the input string @ins, which is in whatever format the loaded NLS 242 * map dictates, into a little endian, 2-byte Unicode string. 243 * 244 * This function allocates the string and the caller is responsible for 245 * calling kmem_cache_free(ntfs_name_cache, @outs); when finished with it. 246 * 247 * On success the function returns the number of Unicode characters written to 248 * the output string *@outs (>= 0), not counting the terminating Unicode NULL 249 * character. *@outs is set to the allocated output string buffer. 250 * 251 * On error, a negative number corresponding to the error code is returned. In 252 * that case the output string is not allocated. Both *@outs and *@outs_len 253 * are then undefined. 254 * 255 * This might look a bit odd due to fast path optimization... 256 */ 257 int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins, 258 const int ins_len, ntfschar **outs) 259 { 260 struct nls_table *nls = vol->nls_map; 261 ntfschar *ucs; 262 wchar_t wc; 263 int i, o, wc_len; 264 265 /* We don't trust outside sources. */ 266 if (ins) { 267 ucs = kmem_cache_alloc(ntfs_name_cache, SLAB_NOFS); 268 if (ucs) { 269 for (i = o = 0; i < ins_len; i += wc_len) { 270 wc_len = nls->char2uni(ins + i, ins_len - i, 271 &wc); 272 if (wc_len >= 0) { 273 if (wc) { 274 ucs[o++] = cpu_to_le16(wc); 275 continue; 276 } /* else (!wc) */ 277 break; 278 } /* else (wc_len < 0) */ 279 goto conversion_err; 280 } 281 ucs[o] = 0; 282 *outs = ucs; 283 return o; 284 } /* else (!ucs) */ 285 ntfs_error(vol->sb, "Failed to allocate name from " 286 "ntfs_name_cache!"); 287 return -ENOMEM; 288 } /* else (!ins) */ 289 ntfs_error(NULL, "Received NULL pointer."); 290 return -EINVAL; 291 conversion_err: 292 ntfs_error(vol->sb, "Name using character set %s contains characters " 293 "that cannot be converted to Unicode.", nls->charset); 294 kmem_cache_free(ntfs_name_cache, ucs); 295 return -EILSEQ; 296 } 297 298 /** 299 * ntfs_ucstonls - convert little endian Unicode string to NLS string 300 * @vol: ntfs volume which we are working with 301 * @ins: input Unicode string buffer 302 * @ins_len: length of input string in Unicode characters 303 * @outs: on return contains the (allocated) output NLS string buffer 304 * @outs_len: length of output string buffer in bytes 305 * 306 * Convert the input little endian, 2-byte Unicode string @ins, of length 307 * @ins_len into the string format dictated by the loaded NLS. 308 * 309 * If *@outs is NULL, this function allocates the string and the caller is 310 * responsible for calling kfree(*@outs); when finished with it. In this case 311 * @outs_len is ignored and can be 0. 312 * 313 * On success the function returns the number of bytes written to the output 314 * string *@outs (>= 0), not counting the terminating NULL byte. If the output 315 * string buffer was allocated, *@outs is set to it. 316 * 317 * On error, a negative number corresponding to the error code is returned. In 318 * that case the output string is not allocated. The contents of *@outs are 319 * then undefined. 320 * 321 * This might look a bit odd due to fast path optimization... 322 */ 323 int ntfs_ucstonls(const ntfs_volume *vol, const ntfschar *ins, 324 const int ins_len, unsigned char **outs, int outs_len) 325 { 326 struct nls_table *nls = vol->nls_map; 327 unsigned char *ns; 328 int i, o, ns_len, wc; 329 330 /* We don't trust outside sources. */ 331 if (ins) { 332 ns = *outs; 333 ns_len = outs_len; 334 if (ns && !ns_len) { 335 wc = -ENAMETOOLONG; 336 goto conversion_err; 337 } 338 if (!ns) { 339 ns_len = ins_len * NLS_MAX_CHARSET_SIZE; 340 ns = (unsigned char*)kmalloc(ns_len + 1, GFP_NOFS); 341 if (!ns) 342 goto mem_err_out; 343 } 344 for (i = o = 0; i < ins_len; i++) { 345 retry: wc = nls->uni2char(le16_to_cpu(ins[i]), ns + o, 346 ns_len - o); 347 if (wc > 0) { 348 o += wc; 349 continue; 350 } else if (!wc) 351 break; 352 else if (wc == -ENAMETOOLONG && ns != *outs) { 353 unsigned char *tc; 354 /* Grow in multiples of 64 bytes. */ 355 tc = (unsigned char*)kmalloc((ns_len + 64) & 356 ~63, GFP_NOFS); 357 if (tc) { 358 memcpy(tc, ns, ns_len); 359 ns_len = ((ns_len + 64) & ~63) - 1; 360 kfree(ns); 361 ns = tc; 362 goto retry; 363 } /* No memory so goto conversion_error; */ 364 } /* wc < 0, real error. */ 365 goto conversion_err; 366 } 367 ns[o] = 0; 368 *outs = ns; 369 return o; 370 } /* else (!ins) */ 371 ntfs_error(vol->sb, "Received NULL pointer."); 372 return -EINVAL; 373 conversion_err: 374 ntfs_error(vol->sb, "Unicode name contains characters that cannot be " 375 "converted to character set %s. You might want to " 376 "try to use the mount option nls=utf8.", nls->charset); 377 if (ns != *outs) 378 kfree(ns); 379 if (wc != -ENAMETOOLONG) 380 wc = -EILSEQ; 381 return wc; 382 mem_err_out: 383 ntfs_error(vol->sb, "Failed to allocate name!"); 384 return -ENOMEM; 385 } 386