1 /* $OpenBSD: msdosfs_conv.c,v 1.1 2016/10/18 17:05:30 natano Exp $ */ 2 /* $NetBSD: msdosfs_conv.c,v 1.24 1997/10/17 11:23:54 ws Exp $ */ 3 4 /*- 5 * Copyright (C) 1995, 1997 Wolfgang Solfrank. 6 * Copyright (C) 1995, 1997 TooLs GmbH. 7 * All rights reserved. 8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by TooLs GmbH. 21 * 4. The name of TooLs GmbH may not be used to endorse or promote products 22 * derived from this software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 /* 36 * Written by Paul Popelka (paulp@uts.amdahl.com) 37 * 38 * You can do anything you want with this software, just don't say you wrote 39 * it, and don't remove this notice. 40 * 41 * This software is provided "as is". 42 * 43 * The author supplies this software to be publicly redistributed on the 44 * understanding that the author is not responsible for the correct 45 * functioning of this software in any circumstances and is not liable for 46 * any damages caused by this software. 47 * 48 * October 1992 49 */ 50 51 /* 52 * System include files. 53 */ 54 #include <sys/param.h> 55 #include <sys/time.h> 56 #include <sys/dirent.h> 57 #include <sys/lock.h> 58 59 /* 60 * MSDOSFS include files. 61 */ 62 #include "msdos/direntry.h" 63 #include "msdos/denode.h" 64 65 /* 66 * Days in each month in a regular year. 67 */ 68 const u_short regyear[] = { 69 31, 28, 31, 30, 31, 30, 70 31, 31, 30, 31, 30, 31 71 }; 72 73 /* 74 * Days in each month in a leap year. 75 */ 76 const u_short leapyear[] = { 77 31, 29, 31, 30, 31, 30, 78 31, 31, 30, 31, 30, 31 79 }; 80 81 /* 82 * Variables used to remember parts of the last time conversion. Maybe we 83 * can avoid a full conversion. 84 */ 85 time_t lasttime; 86 uint32_t lastday; 87 u_short lastddate; 88 u_short lastdtime; 89 90 /* 91 * Convert the unix version of time to dos's idea of time to be used in 92 * file timestamps. The passed in unix time is assumed to be in GMT. 93 */ 94 void 95 unix2dostime(struct timespec *tsp, int minuteswest, u_int16_t *ddp, 96 u_int16_t *dtp, u_int8_t *dhp) 97 { 98 time_t t; 99 uint32_t days; 100 uint32_t inc; 101 uint32_t year; 102 uint32_t month; 103 const u_short *months; 104 105 /* 106 * If the time from the last conversion is the same as now, then 107 * skip the computations and use the saved result. 108 */ 109 t = tsp->tv_sec - (minuteswest * 60) 110 /* +- daylight saving time correction */ ; 111 t &= ~1; 112 /* 113 * Before 1/1/1980 there is only a timeless void. After 12/31/2107 114 * there is only Cthulhu. 115 */ 116 #define DOSEPOCH 315532800LL 117 #define DOSENDTIME 4354775999LL 118 if (t < DOSEPOCH || t > DOSENDTIME) 119 t = DOSEPOCH; 120 121 if (lasttime != t) { 122 lasttime = t; 123 lastdtime = (((t / 2) % 30) << DT_2SECONDS_SHIFT) 124 + (((t / 60) % 60) << DT_MINUTES_SHIFT) 125 + (((t / 3600) % 24) << DT_HOURS_SHIFT); 126 127 /* 128 * If the number of days since 1970 is the same as the last 129 * time we did the computation then skip all this leap year 130 * and month stuff. 131 */ 132 days = t / (24 * 60 * 60); 133 if (days != lastday) { 134 lastday = days; 135 for (year = 1970;; year++) { 136 inc = year & 0x03 ? 365 : 366; 137 if (days < inc) 138 break; 139 days -= inc; 140 } 141 months = year & 0x03 ? regyear : leapyear; 142 for (month = 0; month < 12; month++) { 143 if (days < months[month]) 144 break; 145 days -= months[month]; 146 } 147 lastddate = ((days + 1) << DD_DAY_SHIFT) 148 + ((month + 1) << DD_MONTH_SHIFT); 149 /* 150 * Remember dos's idea of time is relative to 1980. 151 * unix's is relative to 1970. If somehow we get a 152 * time before 1980 then don't give totally crazy 153 * results. 154 */ 155 if (year > 1980) 156 lastddate += (year - 1980) << DD_YEAR_SHIFT; 157 } 158 } 159 160 if (dtp != NULL) 161 *dtp = lastdtime; 162 if (dhp != NULL) 163 *dhp = (tsp->tv_sec & 1) * 100 + tsp->tv_nsec / 10000000; 164 165 *ddp = lastddate; 166 } 167 168 static const u_char 169 unix2dos[256] = { 170 0, 0, 0, 0, 0, 0, 0, 0, /* 00-07 */ 171 0, 0, 0, 0, 0, 0, 0, 0, /* 08-0f */ 172 0, 0, 0, 0, 0, 0, 0, 0, /* 10-17 */ 173 0, 0, 0, 0, 0, 0, 0, 0, /* 18-1f */ 174 0, 0x21, 0, 0x23, 0x24, 0x25, 0x26, 0x27, /* 20-27 */ 175 0x28, 0x29, 0, 0, 0, 0x2d, 0, 0, /* 28-2f */ 176 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 30-37 */ 177 0x38, 0x39, 0, 0, 0, 0, 0, 0, /* 38-3f */ 178 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 40-47 */ 179 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 48-4f */ 180 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 50-57 */ 181 0x58, 0x59, 0x5a, 0, 0, 0, 0x5e, 0x5f, /* 58-5f */ 182 0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 60-67 */ 183 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 68-6f */ 184 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 70-77 */ 185 0x58, 0x59, 0x5a, 0x7b, 0, 0x7d, 0x7e, 0, /* 78-7f */ 186 0, 0, 0, 0, 0, 0, 0, 0, /* 80-87 */ 187 0, 0, 0, 0, 0, 0, 0, 0, /* 88-8f */ 188 0, 0, 0, 0, 0, 0, 0, 0, /* 90-97 */ 189 0, 0, 0, 0, 0, 0, 0, 0, /* 98-9f */ 190 0, 0xad, 0xbd, 0x9c, 0xcf, 0xbe, 0xdd, 0xf5, /* a0-a7 */ 191 0xf9, 0xb8, 0xa6, 0xae, 0xaa, 0xf0, 0xa9, 0xee, /* a8-af */ 192 0xf8, 0xf1, 0xfd, 0xfc, 0xef, 0xe6, 0xf4, 0xfa, /* b0-b7 */ 193 0xf7, 0xfb, 0xa7, 0xaf, 0xac, 0xab, 0xf3, 0xa8, /* b8-bf */ 194 0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80, /* c0-c7 */ 195 0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8, /* c8-cf */ 196 0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0x9e, /* d0-d7 */ 197 0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0xe1, /* d8-df */ 198 0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80, /* e0-e7 */ 199 0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8, /* e8-ef */ 200 0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0xf6, /* f0-f7 */ 201 0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0x98, /* f8-ff */ 202 }; 203 204 static const u_char 205 u2l[256] = { 206 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 00-07 */ 207 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 08-0f */ 208 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 10-17 */ 209 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 18-1f */ 210 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 20-27 */ 211 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 28-2f */ 212 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 30-37 */ 213 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 38-3f */ 214 0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 40-47 */ 215 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 48-4f */ 216 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 50-57 */ 217 0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 58-5f */ 218 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 60-67 */ 219 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 68-6f */ 220 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 70-77 */ 221 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 78-7f */ 222 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 80-87 */ 223 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 88-8f */ 224 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 90-97 */ 225 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 98-9f */ 226 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* a0-a7 */ 227 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* a8-af */ 228 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* b0-b7 */ 229 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* b8-bf */ 230 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* c0-c7 */ 231 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* c8-cf */ 232 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xd7, /* d0-d7 */ 233 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xdf, /* d8-df */ 234 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* e0-e7 */ 235 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* e8-ef */ 236 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* f0-f7 */ 237 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* f8-ff */ 238 }; 239 240 /* 241 * DOS filenames are made of 2 parts, the name part and the extension part. 242 * The name part is 8 characters long and the extension part is 3 243 * characters long. They may contain trailing blanks if the name or 244 * extension are not long enough to fill their respective fields. 245 */ 246 247 /* 248 * Convert a unix filename to a DOS filename according to Win95 rules. 249 * If applicable and gen is not 0, it is inserted into the converted 250 * filename as a generation number. 251 * Returns 252 * 0 if name couldn't be converted 253 * 1 if the converted name is the same as the original 254 * (no long filename entry necessary for Win95) 255 * 2 if conversion was successful 256 * 3 if conversion was successful and generation number was inserted 257 */ 258 int 259 unix2dosfn(u_char *un, u_char dn[11], int unlen, u_int gen) 260 { 261 int i, j, l; 262 int conv = 1; 263 u_char *cp, *dp, *dp1; 264 u_char gentext[6]; 265 266 /* 267 * Fill the dos filename string with blanks. These are DOS's pad 268 * characters. 269 */ 270 for (i = 0; i < 11; i++) 271 dn[i] = ' '; 272 273 /* 274 * The filenames "." and ".." are handled specially, since they 275 * don't follow dos filename rules. 276 */ 277 if (un[0] == '.' && unlen == 1) { 278 dn[0] = '.'; 279 return gen <= 1; 280 } 281 if (un[0] == '.' && un[1] == '.' && unlen == 2) { 282 dn[0] = '.'; 283 dn[1] = '.'; 284 return gen <= 1; 285 } 286 287 /* 288 * Filenames with only blanks and dots are not allowed! 289 */ 290 for (cp = un, i = unlen; --i >= 0; cp++) 291 if (*cp != ' ' && *cp != '.') 292 break; 293 if (i < 0) 294 return 0; 295 296 /* 297 * Now find the extension 298 * Note: dot as first char doesn't start extension 299 * and trailing dots and blanks are ignored 300 */ 301 dp = dp1 = 0; 302 for (cp = un + 1, i = unlen - 1; --i >= 0;) { 303 switch (*cp++) { 304 case '.': 305 if (!dp1) 306 dp1 = cp; 307 break; 308 case ' ': 309 break; 310 default: 311 if (dp1) 312 dp = dp1; 313 dp1 = 0; 314 break; 315 } 316 } 317 318 /* 319 * Now convert it 320 */ 321 if (dp) { 322 if (dp1) 323 l = dp1 - dp; 324 else 325 l = unlen - (dp - un); 326 for (i = 0, j = 8; i < l && j < 11; i++, j++) { 327 if (dp[i] != (dn[j] = unix2dos[dp[i]]) 328 && conv != 3) 329 conv = 2; 330 if (!dn[j]) { 331 conv = 3; 332 dn[j--] = ' '; 333 } 334 } 335 if (i < l) 336 conv = 3; 337 dp--; 338 } else { 339 for (dp = cp; *--dp == ' ' || *dp == '.';); 340 dp++; 341 } 342 343 /* 344 * Now convert the rest of the name 345 */ 346 for (i = j = 0; un < dp && j < 8; i++, j++, un++) { 347 if (*un != (dn[j] = unix2dos[*un]) 348 && conv != 3) 349 conv = 2; 350 if (!dn[j]) { 351 conv = 3; 352 dn[j--] = ' '; 353 } 354 } 355 if (un < dp) 356 conv = 3; 357 /* 358 * If we didn't have any chars in filename, 359 * generate a default 360 */ 361 if (!j) 362 dn[0] = '_'; 363 364 /* 365 * The first character cannot be E5, 366 * because that means a deleted entry 367 */ 368 if (dn[0] == 0xe5) 369 dn[0] = SLOT_E5; 370 371 /* 372 * If there wasn't any char dropped, 373 * there is no place for generation numbers 374 */ 375 if (conv != 3) { 376 if (gen > 1) 377 return 0; 378 return conv; 379 } 380 381 /* 382 * Now insert the generation number into the filename part 383 */ 384 for (cp = gentext + sizeof(gentext); cp > gentext && gen; gen /= 10) 385 *--cp = gen % 10 + '0'; 386 if (gen) 387 return 0; 388 for (i = 8; dn[--i] == ' ';); 389 if (gentext + sizeof(gentext) - cp + 1 > 8 - i) 390 i = 8 - (gentext + sizeof(gentext) - cp + 1); 391 dn[i++] = '~'; 392 while (cp < gentext + sizeof(gentext)) 393 dn[i++] = *cp++; 394 return 3; 395 } 396 397 /* 398 * Create a Win95 long name directory entry 399 * Note: assumes that the filename is valid, 400 * i.e. doesn't consist solely of blanks and dots 401 */ 402 int 403 unix2winfn(u_char *un, int unlen, struct winentry *wep, int cnt, int chksum) 404 { 405 u_int8_t *cp; 406 int i; 407 408 /* 409 * Drop trailing blanks and dots 410 */ 411 for (cp = un + unlen; *--cp == ' ' || *cp == '.'; unlen--); 412 413 un += (cnt - 1) * WIN_CHARS; 414 unlen -= (cnt - 1) * WIN_CHARS; 415 416 /* 417 * Initialize winentry to some useful default 418 */ 419 for (cp = (u_int8_t *)wep, i = sizeof(*wep); --i >= 0; *cp++ = 0xff); 420 wep->weCnt = cnt; 421 wep->weAttributes = ATTR_WIN95; 422 wep->weReserved1 = 0; 423 wep->weChksum = chksum; 424 wep->weReserved2 = 0; 425 426 /* 427 * Now convert the filename parts 428 */ 429 for (cp = wep->wePart1, i = sizeof(wep->wePart1)/2; --i >= 0;) { 430 if (--unlen < 0) 431 goto done; 432 *cp++ = *un++; 433 *cp++ = 0; 434 } 435 for (cp = wep->wePart2, i = sizeof(wep->wePart2)/2; --i >= 0;) { 436 if (--unlen < 0) 437 goto done; 438 *cp++ = *un++; 439 *cp++ = 0; 440 } 441 for (cp = wep->wePart3, i = sizeof(wep->wePart3)/2; --i >= 0;) { 442 if (--unlen < 0) 443 goto done; 444 *cp++ = *un++; 445 *cp++ = 0; 446 } 447 if (!unlen) 448 wep->weCnt |= WIN_LAST; 449 return unlen; 450 451 done: 452 *cp++ = 0; 453 *cp++ = 0; 454 wep->weCnt |= WIN_LAST; 455 return 0; 456 } 457 458 /* 459 * Compare our filename to the one in the Win95 entry 460 * Returns the checksum or -1 if no match 461 */ 462 int 463 winChkName(u_char *un, int unlen, struct winentry *wep, int chksum) 464 { 465 u_int8_t *cp; 466 int i; 467 468 /* 469 * First compare checksums 470 */ 471 if (wep->weCnt&WIN_LAST) 472 chksum = wep->weChksum; 473 else if (chksum != wep->weChksum) 474 chksum = -1; 475 if (chksum == -1) 476 return -1; 477 478 /* 479 * Offset of this entry 480 */ 481 i = ((wep->weCnt&WIN_CNT) - 1) * WIN_CHARS; 482 if ((unlen -= i) <= 0) 483 return -1; 484 un += i; 485 486 if ((wep->weCnt&WIN_LAST) && unlen > WIN_CHARS) 487 return -1; 488 489 /* 490 * Compare the name parts 491 */ 492 for (cp = wep->wePart1, i = sizeof(wep->wePart1)/2; --i >= 0;) { 493 if (--unlen < 0) { 494 if (!*cp++ && !*cp) 495 return chksum; 496 return -1; 497 } 498 if (u2l[*cp++] != u2l[*un++] || *cp++) 499 return -1; 500 } 501 for (cp = wep->wePart2, i = sizeof(wep->wePart2)/2; --i >= 0;) { 502 if (--unlen < 0) { 503 if (!*cp++ && !*cp) 504 return chksum; 505 return -1; 506 } 507 if (u2l[*cp++] != u2l[*un++] || *cp++) 508 return -1; 509 } 510 for (cp = wep->wePart3, i = sizeof(wep->wePart3)/2; --i >= 0;) { 511 if (--unlen < 0) { 512 if (!*cp++ && !*cp) 513 return chksum; 514 return -1; 515 } 516 if (u2l[*cp++] != u2l[*un++] || *cp++) 517 return -1; 518 } 519 return chksum; 520 } 521 522 /* 523 * Compute the checksum of a DOS filename for Win95 use 524 */ 525 u_int8_t 526 winChksum(u_int8_t *name) 527 { 528 int i; 529 u_int8_t s; 530 531 for (s = 0, i = 11; --i >= 0; s += *name++) 532 s = (s << 7)|(s >> 1); 533 return s; 534 } 535 536 /* 537 * Determine the number of slots necessary for Win95 names 538 */ 539 int 540 winSlotCnt(u_char *un, int unlen) 541 { 542 for (un += unlen; unlen > 0; unlen--) 543 if (*--un != ' ' && *un != '.') 544 break; 545 if (unlen > WIN_MAXLEN) 546 return 0; 547 return howmany(unlen, WIN_CHARS); 548 } 549