1 /* 2 * unicode.c 3 * 4 * PURPOSE 5 * Routines for converting between UTF-8 and OSTA Compressed Unicode. 6 * Also handles filename mangling 7 * 8 * DESCRIPTION 9 * OSTA Compressed Unicode is explained in the OSTA UDF specification. 10 * http://www.osta.org/ 11 * UTF-8 is explained in the IETF RFC XXXX. 12 * ftp://ftp.internic.net/rfc/rfcxxxx.txt 13 * 14 * COPYRIGHT 15 * This file is distributed under the terms of the GNU General Public 16 * License (GPL). Copies of the GPL can be obtained from: 17 * ftp://prep.ai.mit.edu/pub/gnu/GPL 18 * Each contributing author retains all rights to their own work. 19 */ 20 21 #include "udfdecl.h" 22 23 #include <linux/kernel.h> 24 #include <linux/string.h> /* for memset */ 25 #include <linux/nls.h> 26 #include <linux/crc-itu-t.h> 27 #include <linux/slab.h> 28 29 #include "udf_sb.h" 30 31 static int udf_translate_to_linux(uint8_t *, int, uint8_t *, int, uint8_t *, 32 int); 33 34 static int udf_char_to_ustr(struct ustr *dest, const uint8_t *src, int strlen) 35 { 36 if ((!dest) || (!src) || (!strlen) || (strlen > UDF_NAME_LEN - 2)) 37 return 0; 38 39 memset(dest, 0, sizeof(struct ustr)); 40 memcpy(dest->u_name, src, strlen); 41 dest->u_cmpID = 0x08; 42 dest->u_len = strlen; 43 44 return strlen; 45 } 46 47 /* 48 * udf_build_ustr 49 */ 50 int udf_build_ustr(struct ustr *dest, dstring *ptr, int size) 51 { 52 int usesize; 53 54 if (!dest || !ptr || !size) 55 return -1; 56 BUG_ON(size < 2); 57 58 usesize = min_t(size_t, ptr[size - 1], sizeof(dest->u_name)); 59 usesize = min(usesize, size - 2); 60 dest->u_cmpID = ptr[0]; 61 dest->u_len = usesize; 62 memcpy(dest->u_name, ptr + 1, usesize); 63 memset(dest->u_name + usesize, 0, sizeof(dest->u_name) - usesize); 64 65 return 0; 66 } 67 68 /* 69 * udf_build_ustr_exact 70 */ 71 static void udf_build_ustr_exact(struct ustr *dest, dstring *ptr, int exactsize) 72 { 73 memset(dest, 0, sizeof(struct ustr)); 74 dest->u_cmpID = ptr[0]; 75 dest->u_len = exactsize - 1; 76 memcpy(dest->u_name, ptr + 1, exactsize - 1); 77 } 78 79 /* 80 * udf_CS0toUTF8 81 * 82 * PURPOSE 83 * Convert OSTA Compressed Unicode to the UTF-8 equivalent. 84 * 85 * PRE-CONDITIONS 86 * utf Pointer to UTF-8 output buffer. 87 * ocu Pointer to OSTA Compressed Unicode input buffer 88 * of size UDF_NAME_LEN bytes. 89 * both of type "struct ustr *" 90 * 91 * POST-CONDITIONS 92 * <return> >= 0 on success. 93 * 94 * HISTORY 95 * November 12, 1997 - Andrew E. Mileski 96 * Written, tested, and released. 97 */ 98 int udf_CS0toUTF8(struct ustr *utf_o, const struct ustr *ocu_i) 99 { 100 const uint8_t *ocu; 101 uint8_t cmp_id, ocu_len; 102 int i; 103 104 ocu_len = ocu_i->u_len; 105 if (ocu_len == 0) { 106 memset(utf_o, 0, sizeof(struct ustr)); 107 return 0; 108 } 109 110 cmp_id = ocu_i->u_cmpID; 111 if (cmp_id != 8 && cmp_id != 16) { 112 memset(utf_o, 0, sizeof(struct ustr)); 113 pr_err("unknown compression code (%d) stri=%s\n", 114 cmp_id, ocu_i->u_name); 115 return -EINVAL; 116 } 117 118 ocu = ocu_i->u_name; 119 utf_o->u_len = 0; 120 for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN - 3));) { 121 122 /* Expand OSTA compressed Unicode to Unicode */ 123 uint32_t c = ocu[i++]; 124 if (cmp_id == 16) 125 c = (c << 8) | ocu[i++]; 126 127 /* Compress Unicode to UTF-8 */ 128 if (c < 0x80U) 129 utf_o->u_name[utf_o->u_len++] = (uint8_t)c; 130 else if (c < 0x800U) { 131 utf_o->u_name[utf_o->u_len++] = 132 (uint8_t)(0xc0 | (c >> 6)); 133 utf_o->u_name[utf_o->u_len++] = 134 (uint8_t)(0x80 | (c & 0x3f)); 135 } else { 136 utf_o->u_name[utf_o->u_len++] = 137 (uint8_t)(0xe0 | (c >> 12)); 138 utf_o->u_name[utf_o->u_len++] = 139 (uint8_t)(0x80 | 140 ((c >> 6) & 0x3f)); 141 utf_o->u_name[utf_o->u_len++] = 142 (uint8_t)(0x80 | (c & 0x3f)); 143 } 144 } 145 utf_o->u_cmpID = 8; 146 147 return utf_o->u_len; 148 } 149 150 /* 151 * 152 * udf_UTF8toCS0 153 * 154 * PURPOSE 155 * Convert UTF-8 to the OSTA Compressed Unicode equivalent. 156 * 157 * DESCRIPTION 158 * This routine is only called by udf_lookup(). 159 * 160 * PRE-CONDITIONS 161 * ocu Pointer to OSTA Compressed Unicode output 162 * buffer of size UDF_NAME_LEN bytes. 163 * utf Pointer to UTF-8 input buffer. 164 * utf_len Length of UTF-8 input buffer in bytes. 165 * 166 * POST-CONDITIONS 167 * <return> Zero on success. 168 * 169 * HISTORY 170 * November 12, 1997 - Andrew E. Mileski 171 * Written, tested, and released. 172 */ 173 static int udf_UTF8toCS0(dstring *ocu, struct ustr *utf, int length) 174 { 175 unsigned c, i, max_val, utf_char; 176 int utf_cnt, u_len; 177 178 memset(ocu, 0, sizeof(dstring) * length); 179 ocu[0] = 8; 180 max_val = 0xffU; 181 182 try_again: 183 u_len = 0U; 184 utf_char = 0U; 185 utf_cnt = 0U; 186 for (i = 0U; i < utf->u_len; i++) { 187 c = (uint8_t)utf->u_name[i]; 188 189 /* Complete a multi-byte UTF-8 character */ 190 if (utf_cnt) { 191 utf_char = (utf_char << 6) | (c & 0x3fU); 192 if (--utf_cnt) 193 continue; 194 } else { 195 /* Check for a multi-byte UTF-8 character */ 196 if (c & 0x80U) { 197 /* Start a multi-byte UTF-8 character */ 198 if ((c & 0xe0U) == 0xc0U) { 199 utf_char = c & 0x1fU; 200 utf_cnt = 1; 201 } else if ((c & 0xf0U) == 0xe0U) { 202 utf_char = c & 0x0fU; 203 utf_cnt = 2; 204 } else if ((c & 0xf8U) == 0xf0U) { 205 utf_char = c & 0x07U; 206 utf_cnt = 3; 207 } else if ((c & 0xfcU) == 0xf8U) { 208 utf_char = c & 0x03U; 209 utf_cnt = 4; 210 } else if ((c & 0xfeU) == 0xfcU) { 211 utf_char = c & 0x01U; 212 utf_cnt = 5; 213 } else { 214 goto error_out; 215 } 216 continue; 217 } else { 218 /* Single byte UTF-8 character (most common) */ 219 utf_char = c; 220 } 221 } 222 223 /* Choose no compression if necessary */ 224 if (utf_char > max_val) { 225 if (max_val == 0xffU) { 226 max_val = 0xffffU; 227 ocu[0] = (uint8_t)0x10U; 228 goto try_again; 229 } 230 goto error_out; 231 } 232 233 if (max_val == 0xffffU) 234 ocu[++u_len] = (uint8_t)(utf_char >> 8); 235 ocu[++u_len] = (uint8_t)(utf_char & 0xffU); 236 } 237 238 if (utf_cnt) { 239 error_out: 240 ocu[++u_len] = '?'; 241 printk(KERN_DEBUG pr_fmt("bad UTF-8 character\n")); 242 } 243 244 ocu[length - 1] = (uint8_t)u_len + 1; 245 246 return u_len + 1; 247 } 248 249 static int udf_CS0toNLS(struct nls_table *nls, struct ustr *utf_o, 250 const struct ustr *ocu_i) 251 { 252 const uint8_t *ocu; 253 uint8_t cmp_id, ocu_len; 254 int i, len; 255 256 257 ocu_len = ocu_i->u_len; 258 if (ocu_len == 0) { 259 memset(utf_o, 0, sizeof(struct ustr)); 260 return 0; 261 } 262 263 cmp_id = ocu_i->u_cmpID; 264 if (cmp_id != 8 && cmp_id != 16) { 265 memset(utf_o, 0, sizeof(struct ustr)); 266 pr_err("unknown compression code (%d) stri=%s\n", 267 cmp_id, ocu_i->u_name); 268 return -EINVAL; 269 } 270 271 ocu = ocu_i->u_name; 272 utf_o->u_len = 0; 273 for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN - 3));) { 274 /* Expand OSTA compressed Unicode to Unicode */ 275 uint32_t c = ocu[i++]; 276 if (cmp_id == 16) 277 c = (c << 8) | ocu[i++]; 278 279 len = nls->uni2char(c, &utf_o->u_name[utf_o->u_len], 280 UDF_NAME_LEN - utf_o->u_len); 281 /* Valid character? */ 282 if (len >= 0) 283 utf_o->u_len += len; 284 else 285 utf_o->u_name[utf_o->u_len++] = '?'; 286 } 287 utf_o->u_cmpID = 8; 288 289 return utf_o->u_len; 290 } 291 292 static int udf_NLStoCS0(struct nls_table *nls, dstring *ocu, struct ustr *uni, 293 int length) 294 { 295 int len; 296 unsigned i, max_val; 297 uint16_t uni_char; 298 int u_len; 299 300 memset(ocu, 0, sizeof(dstring) * length); 301 ocu[0] = 8; 302 max_val = 0xffU; 303 304 try_again: 305 u_len = 0U; 306 for (i = 0U; i < uni->u_len; i++) { 307 len = nls->char2uni(&uni->u_name[i], uni->u_len - i, &uni_char); 308 if (!len) 309 continue; 310 /* Invalid character, deal with it */ 311 if (len < 0) { 312 len = 1; 313 uni_char = '?'; 314 } 315 316 if (uni_char > max_val) { 317 max_val = 0xffffU; 318 ocu[0] = (uint8_t)0x10U; 319 goto try_again; 320 } 321 322 if (max_val == 0xffffU) 323 ocu[++u_len] = (uint8_t)(uni_char >> 8); 324 ocu[++u_len] = (uint8_t)(uni_char & 0xffU); 325 i += len - 1; 326 } 327 328 ocu[length - 1] = (uint8_t)u_len + 1; 329 return u_len + 1; 330 } 331 332 int udf_get_filename(struct super_block *sb, uint8_t *sname, int slen, 333 uint8_t *dname, int dlen) 334 { 335 struct ustr *filename, *unifilename; 336 int ret = 0; 337 338 if (!slen) 339 return -EIO; 340 341 filename = kmalloc(sizeof(struct ustr), GFP_NOFS); 342 if (!filename) 343 return -ENOMEM; 344 345 unifilename = kmalloc(sizeof(struct ustr), GFP_NOFS); 346 if (!unifilename) { 347 ret = -ENOMEM; 348 goto out1; 349 } 350 351 udf_build_ustr_exact(unifilename, sname, slen); 352 if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) { 353 ret = udf_CS0toUTF8(filename, unifilename); 354 if (ret < 0) { 355 udf_debug("Failed in udf_get_filename: sname = %s\n", 356 sname); 357 goto out2; 358 } 359 } else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) { 360 ret = udf_CS0toNLS(UDF_SB(sb)->s_nls_map, filename, 361 unifilename); 362 if (ret < 0) { 363 udf_debug("Failed in udf_get_filename: sname = %s\n", 364 sname); 365 goto out2; 366 } 367 } else 368 BUG(); 369 370 ret = udf_translate_to_linux(dname, dlen, 371 filename->u_name, filename->u_len, 372 unifilename->u_name, unifilename->u_len); 373 out2: 374 kfree(unifilename); 375 out1: 376 kfree(filename); 377 return ret; 378 } 379 380 int udf_put_filename(struct super_block *sb, const uint8_t *sname, 381 uint8_t *dname, int flen) 382 { 383 struct ustr unifilename; 384 int namelen; 385 386 if (!udf_char_to_ustr(&unifilename, sname, flen)) 387 return 0; 388 389 if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) { 390 namelen = udf_UTF8toCS0(dname, &unifilename, UDF_NAME_LEN); 391 if (!namelen) 392 return 0; 393 } else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) { 394 namelen = udf_NLStoCS0(UDF_SB(sb)->s_nls_map, dname, 395 &unifilename, UDF_NAME_LEN); 396 if (!namelen) 397 return 0; 398 } else 399 return 0; 400 401 return namelen; 402 } 403 404 #define ILLEGAL_CHAR_MARK '_' 405 #define EXT_MARK '.' 406 #define CRC_MARK '#' 407 #define EXT_SIZE 5 408 /* Number of chars we need to store generated CRC to make filename unique */ 409 #define CRC_LEN 5 410 411 static int udf_translate_to_linux(uint8_t *newName, int newLen, 412 uint8_t *udfName, int udfLen, 413 uint8_t *fidName, int fidNameLen) 414 { 415 int index, newIndex = 0, needsCRC = 0; 416 int extIndex = 0, newExtIndex = 0, hasExt = 0; 417 unsigned short valueCRC; 418 uint8_t curr; 419 420 if (udfName[0] == '.' && 421 (udfLen == 1 || (udfLen == 2 && udfName[1] == '.'))) { 422 needsCRC = 1; 423 newIndex = udfLen; 424 memcpy(newName, udfName, udfLen); 425 } else { 426 for (index = 0; index < udfLen; index++) { 427 curr = udfName[index]; 428 if (curr == '/' || curr == 0) { 429 needsCRC = 1; 430 curr = ILLEGAL_CHAR_MARK; 431 while (index + 1 < udfLen && 432 (udfName[index + 1] == '/' || 433 udfName[index + 1] == 0)) 434 index++; 435 } 436 if (curr == EXT_MARK && 437 (udfLen - index - 1) <= EXT_SIZE) { 438 if (udfLen == index + 1) 439 hasExt = 0; 440 else { 441 hasExt = 1; 442 extIndex = index; 443 newExtIndex = newIndex; 444 } 445 } 446 if (newIndex < newLen) 447 newName[newIndex++] = curr; 448 else 449 needsCRC = 1; 450 } 451 } 452 if (needsCRC) { 453 uint8_t ext[EXT_SIZE]; 454 int localExtIndex = 0; 455 456 if (hasExt) { 457 int maxFilenameLen; 458 for (index = 0; 459 index < EXT_SIZE && extIndex + index + 1 < udfLen; 460 index++) { 461 curr = udfName[extIndex + index + 1]; 462 463 if (curr == '/' || curr == 0) { 464 needsCRC = 1; 465 curr = ILLEGAL_CHAR_MARK; 466 while (extIndex + index + 2 < udfLen && 467 (index + 1 < EXT_SIZE && 468 (udfName[extIndex + index + 2] == '/' || 469 udfName[extIndex + index + 2] == 0))) 470 index++; 471 } 472 ext[localExtIndex++] = curr; 473 } 474 maxFilenameLen = newLen - CRC_LEN - localExtIndex; 475 if (newIndex > maxFilenameLen) 476 newIndex = maxFilenameLen; 477 else 478 newIndex = newExtIndex; 479 } else if (newIndex > newLen - CRC_LEN) 480 newIndex = newLen - CRC_LEN; 481 newName[newIndex++] = CRC_MARK; 482 valueCRC = crc_itu_t(0, fidName, fidNameLen); 483 newName[newIndex++] = hex_asc_upper_hi(valueCRC >> 8); 484 newName[newIndex++] = hex_asc_upper_lo(valueCRC >> 8); 485 newName[newIndex++] = hex_asc_upper_hi(valueCRC); 486 newName[newIndex++] = hex_asc_upper_lo(valueCRC); 487 488 if (hasExt) { 489 newName[newIndex++] = EXT_MARK; 490 for (index = 0; index < localExtIndex; index++) 491 newName[newIndex++] = ext[index]; 492 } 493 } 494 495 return newIndex; 496 } 497