1 /* $OpenBSD: msdosfs_conv.c,v 1.3 2023/08/11 04:51:36 guenther 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/time.h> 55 #include <sys/dirent.h> 56 #include <sys/lock.h> 57 58 /* 59 * MSDOSFS include files. 60 */ 61 #include "msdos/direntry.h" 62 #include "msdos/denode.h" 63 64 /* 65 * Days in each month in a regular year. 66 */ 67 const u_short regyear[] = { 68 31, 28, 31, 30, 31, 30, 69 31, 31, 30, 31, 30, 31 70 }; 71 72 /* 73 * Days in each month in a leap year. 74 */ 75 const u_short leapyear[] = { 76 31, 29, 31, 30, 31, 30, 77 31, 31, 30, 31, 30, 31 78 }; 79 80 /* 81 * Variables used to remember parts of the last time conversion. Maybe we 82 * can avoid a full conversion. 83 */ 84 time_t lasttime; 85 uint32_t lastday; 86 u_short lastddate; 87 u_short lastdtime; 88 89 /* 90 * Convert the unix version of time to dos's idea of time to be used in 91 * file timestamps. The passed in unix time is assumed to be in GMT. 92 */ 93 void 94 unix2dostime(const struct timespec *tsp, int minuteswest, u_int16_t *ddp, 95 u_int16_t *dtp, u_int8_t *dhp) 96 { 97 time_t t; 98 uint32_t days; 99 uint32_t inc; 100 uint32_t year; 101 uint32_t month; 102 const u_short *months; 103 104 /* 105 * If the time from the last conversion is the same as now, then 106 * skip the computations and use the saved result. 107 */ 108 t = tsp->tv_sec - (minuteswest * 60) 109 /* +- daylight saving time correction */ ; 110 t &= ~1; 111 /* 112 * Before 1/1/1980 there is only a timeless void. After 12/31/2107 113 * there is only Cthulhu. 114 */ 115 #define DOSEPOCH 315532800LL 116 #define DOSENDTIME 4354775999LL 117 if (t < DOSEPOCH || t > DOSENDTIME) 118 t = DOSEPOCH; 119 120 if (lasttime != t) { 121 lasttime = t; 122 lastdtime = (((t / 2) % 30) << DT_2SECONDS_SHIFT) 123 + (((t / 60) % 60) << DT_MINUTES_SHIFT) 124 + (((t / 3600) % 24) << DT_HOURS_SHIFT); 125 126 /* 127 * If the number of days since 1970 is the same as the last 128 * time we did the computation then skip all this leap year 129 * and month stuff. 130 */ 131 days = t / (24 * 60 * 60); 132 if (days != lastday) { 133 lastday = days; 134 for (year = 1970;; year++) { 135 inc = year & 0x03 ? 365 : 366; 136 if (days < inc) 137 break; 138 days -= inc; 139 } 140 months = year & 0x03 ? regyear : leapyear; 141 for (month = 0; month < 12; month++) { 142 if (days < months[month]) 143 break; 144 days -= months[month]; 145 } 146 lastddate = ((days + 1) << DD_DAY_SHIFT) 147 + ((month + 1) << DD_MONTH_SHIFT); 148 /* 149 * Remember dos's idea of time is relative to 1980. 150 * unix's is relative to 1970. If somehow we get a 151 * time before 1980 then don't give totally crazy 152 * results. 153 */ 154 if (year > 1980) 155 lastddate += (year - 1980) << DD_YEAR_SHIFT; 156 } 157 } 158 159 if (dtp != NULL) 160 *dtp = lastdtime; 161 if (dhp != NULL) 162 *dhp = (tsp->tv_sec & 1) * 100 + tsp->tv_nsec / 10000000; 163 164 *ddp = lastddate; 165 } 166 167 static const u_char 168 unix2dos[256] = { 169 0, 0, 0, 0, 0, 0, 0, 0, /* 00-07 */ 170 0, 0, 0, 0, 0, 0, 0, 0, /* 08-0f */ 171 0, 0, 0, 0, 0, 0, 0, 0, /* 10-17 */ 172 0, 0, 0, 0, 0, 0, 0, 0, /* 18-1f */ 173 0, 0x21, 0, 0x23, 0x24, 0x25, 0x26, 0x27, /* 20-27 */ 174 0x28, 0x29, 0, 0, 0, 0x2d, 0, 0, /* 28-2f */ 175 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 30-37 */ 176 0x38, 0x39, 0, 0, 0, 0, 0, 0, /* 38-3f */ 177 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 40-47 */ 178 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 48-4f */ 179 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 50-57 */ 180 0x58, 0x59, 0x5a, 0, 0, 0, 0x5e, 0x5f, /* 58-5f */ 181 0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, /* 60-67 */ 182 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, /* 68-6f */ 183 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, /* 70-77 */ 184 0x58, 0x59, 0x5a, 0x7b, 0, 0x7d, 0x7e, 0, /* 78-7f */ 185 0, 0, 0, 0, 0, 0, 0, 0, /* 80-87 */ 186 0, 0, 0, 0, 0, 0, 0, 0, /* 88-8f */ 187 0, 0, 0, 0, 0, 0, 0, 0, /* 90-97 */ 188 0, 0, 0, 0, 0, 0, 0, 0, /* 98-9f */ 189 0, 0xad, 0xbd, 0x9c, 0xcf, 0xbe, 0xdd, 0xf5, /* a0-a7 */ 190 0xf9, 0xb8, 0xa6, 0xae, 0xaa, 0xf0, 0xa9, 0xee, /* a8-af */ 191 0xf8, 0xf1, 0xfd, 0xfc, 0xef, 0xe6, 0xf4, 0xfa, /* b0-b7 */ 192 0xf7, 0xfb, 0xa7, 0xaf, 0xac, 0xab, 0xf3, 0xa8, /* b8-bf */ 193 0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80, /* c0-c7 */ 194 0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8, /* c8-cf */ 195 0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0x9e, /* d0-d7 */ 196 0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0xe1, /* d8-df */ 197 0xb7, 0xb5, 0xb6, 0xc7, 0x8e, 0x8f, 0x92, 0x80, /* e0-e7 */ 198 0xd4, 0x90, 0xd2, 0xd3, 0xde, 0xd6, 0xd7, 0xd8, /* e8-ef */ 199 0xd1, 0xa5, 0xe3, 0xe0, 0xe2, 0xe5, 0x99, 0xf6, /* f0-f7 */ 200 0x9d, 0xeb, 0xe9, 0xea, 0x9a, 0xed, 0xe8, 0x98, /* f8-ff */ 201 }; 202 203 static const u_char 204 u2l[256] = { 205 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, /* 00-07 */ 206 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, /* 08-0f */ 207 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, /* 10-17 */ 208 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, /* 18-1f */ 209 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, /* 20-27 */ 210 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, /* 28-2f */ 211 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, /* 30-37 */ 212 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, /* 38-3f */ 213 0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 40-47 */ 214 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 48-4f */ 215 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 50-57 */ 216 0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, /* 58-5f */ 217 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, /* 60-67 */ 218 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, /* 68-6f */ 219 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, /* 70-77 */ 220 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, /* 78-7f */ 221 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, /* 80-87 */ 222 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, /* 88-8f */ 223 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, /* 90-97 */ 224 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, /* 98-9f */ 225 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, /* a0-a7 */ 226 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, /* a8-af */ 227 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, /* b0-b7 */ 228 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, /* b8-bf */ 229 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* c0-c7 */ 230 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* c8-cf */ 231 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xd7, /* d0-d7 */ 232 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xdf, /* d8-df */ 233 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, /* e0-e7 */ 234 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, /* e8-ef */ 235 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, /* f0-f7 */ 236 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, /* f8-ff */ 237 }; 238 239 /* 240 * DOS filenames are made of 2 parts, the name part and the extension part. 241 * The name part is 8 characters long and the extension part is 3 242 * characters long. They may contain trailing blanks if the name or 243 * extension are not long enough to fill their respective fields. 244 */ 245 246 /* 247 * Convert a unix filename to a DOS filename according to Win95 rules. 248 * If applicable and gen is not 0, it is inserted into the converted 249 * filename as a generation number. 250 * Returns 251 * 0 if name couldn't be converted 252 * 1 if the converted name is the same as the original 253 * (no long filename entry necessary for Win95) 254 * 2 if conversion was successful 255 * 3 if conversion was successful and generation number was inserted 256 */ 257 int 258 unix2dosfn(u_char *un, u_char dn[11], int unlen, u_int gen) 259 { 260 int i, j, l; 261 int conv = 1; 262 u_char *cp, *dp, *dp1; 263 u_char gentext[6]; 264 265 /* 266 * Fill the dos filename string with blanks. These are DOS's pad 267 * characters. 268 */ 269 for (i = 0; i < 11; i++) 270 dn[i] = ' '; 271 272 /* 273 * The filenames "." and ".." are handled specially, since they 274 * don't follow dos filename rules. 275 */ 276 if (un[0] == '.' && unlen == 1) { 277 dn[0] = '.'; 278 return gen <= 1; 279 } 280 if (un[0] == '.' && un[1] == '.' && unlen == 2) { 281 dn[0] = '.'; 282 dn[1] = '.'; 283 return gen <= 1; 284 } 285 286 /* 287 * Filenames with only blanks and dots are not allowed! 288 */ 289 for (cp = un, i = unlen; --i >= 0; cp++) 290 if (*cp != ' ' && *cp != '.') 291 break; 292 if (i < 0) 293 return 0; 294 295 /* 296 * Now find the extension 297 * Note: dot as first char doesn't start extension 298 * and trailing dots and blanks are ignored 299 */ 300 dp = dp1 = 0; 301 for (cp = un + 1, i = unlen - 1; --i >= 0;) { 302 switch (*cp++) { 303 case '.': 304 if (!dp1) 305 dp1 = cp; 306 break; 307 case ' ': 308 break; 309 default: 310 if (dp1) 311 dp = dp1; 312 dp1 = 0; 313 break; 314 } 315 } 316 317 /* 318 * Now convert it 319 */ 320 if (dp) { 321 if (dp1) 322 l = dp1 - dp; 323 else 324 l = unlen - (dp - un); 325 for (i = 0, j = 8; i < l && j < 11; i++, j++) { 326 if (dp[i] != (dn[j] = unix2dos[dp[i]]) 327 && conv != 3) 328 conv = 2; 329 if (!dn[j]) { 330 conv = 3; 331 dn[j--] = ' '; 332 } 333 } 334 if (i < l) 335 conv = 3; 336 dp--; 337 } else { 338 for (dp = cp; *--dp == ' ' || *dp == '.';); 339 dp++; 340 } 341 342 /* 343 * Now convert the rest of the name 344 */ 345 for (i = j = 0; un < dp && j < 8; i++, j++, un++) { 346 if (*un != (dn[j] = unix2dos[*un]) 347 && conv != 3) 348 conv = 2; 349 if (!dn[j]) { 350 conv = 3; 351 dn[j--] = ' '; 352 } 353 } 354 if (un < dp) 355 conv = 3; 356 /* 357 * If we didn't have any chars in filename, 358 * generate a default 359 */ 360 if (!j) 361 dn[0] = '_'; 362 363 /* 364 * The first character cannot be E5, 365 * because that means a deleted entry 366 */ 367 if (dn[0] == 0xe5) 368 dn[0] = SLOT_E5; 369 370 /* 371 * If there wasn't any char dropped, 372 * there is no place for generation numbers 373 */ 374 if (conv != 3) { 375 if (gen > 1) 376 return 0; 377 return conv; 378 } 379 380 /* 381 * Now insert the generation number into the filename part 382 */ 383 for (cp = gentext + sizeof(gentext); cp > gentext && gen; gen /= 10) 384 *--cp = gen % 10 + '0'; 385 if (gen) 386 return 0; 387 for (i = 8; dn[--i] == ' ';); 388 if (gentext + sizeof(gentext) - cp + 1 > 8 - i) 389 i = 8 - (gentext + sizeof(gentext) - cp + 1); 390 dn[i++] = '~'; 391 while (cp < gentext + sizeof(gentext)) 392 dn[i++] = *cp++; 393 return 3; 394 } 395 396 /* 397 * Create a Win95 long name directory entry 398 * Note: assumes that the filename is valid, 399 * i.e. doesn't consist solely of blanks and dots 400 */ 401 int 402 unix2winfn(u_char *un, int unlen, struct winentry *wep, int cnt, int chksum) 403 { 404 u_int8_t *cp; 405 int i; 406 407 /* 408 * Drop trailing blanks and dots 409 */ 410 for (cp = un + unlen; *--cp == ' ' || *cp == '.'; unlen--); 411 412 un += (cnt - 1) * WIN_CHARS; 413 unlen -= (cnt - 1) * WIN_CHARS; 414 415 /* 416 * Initialize winentry to some useful default 417 */ 418 for (cp = (u_int8_t *)wep, i = sizeof(*wep); --i >= 0; *cp++ = 0xff); 419 wep->weCnt = cnt; 420 wep->weAttributes = ATTR_WIN95; 421 wep->weReserved1 = 0; 422 wep->weChksum = chksum; 423 wep->weReserved2 = 0; 424 425 /* 426 * Now convert the filename parts 427 */ 428 for (cp = wep->wePart1, i = sizeof(wep->wePart1)/2; --i >= 0;) { 429 if (--unlen < 0) 430 goto done; 431 *cp++ = *un++; 432 *cp++ = 0; 433 } 434 for (cp = wep->wePart2, i = sizeof(wep->wePart2)/2; --i >= 0;) { 435 if (--unlen < 0) 436 goto done; 437 *cp++ = *un++; 438 *cp++ = 0; 439 } 440 for (cp = wep->wePart3, i = sizeof(wep->wePart3)/2; --i >= 0;) { 441 if (--unlen < 0) 442 goto done; 443 *cp++ = *un++; 444 *cp++ = 0; 445 } 446 if (!unlen) 447 wep->weCnt |= WIN_LAST; 448 return unlen; 449 450 done: 451 *cp++ = 0; 452 *cp++ = 0; 453 wep->weCnt |= WIN_LAST; 454 return 0; 455 } 456 457 /* 458 * Compare our filename to the one in the Win95 entry 459 * Returns the checksum or -1 if no match 460 */ 461 int 462 winChkName(u_char *un, int unlen, struct winentry *wep, int chksum) 463 { 464 u_int8_t *cp; 465 int i; 466 467 /* 468 * First compare checksums 469 */ 470 if (wep->weCnt&WIN_LAST) 471 chksum = wep->weChksum; 472 else if (chksum != wep->weChksum) 473 chksum = -1; 474 if (chksum == -1) 475 return -1; 476 477 /* 478 * Offset of this entry 479 */ 480 i = ((wep->weCnt&WIN_CNT) - 1) * WIN_CHARS; 481 if ((unlen -= i) <= 0) 482 return -1; 483 un += i; 484 485 if ((wep->weCnt&WIN_LAST) && unlen > WIN_CHARS) 486 return -1; 487 488 /* 489 * Compare the name parts 490 */ 491 for (cp = wep->wePart1, i = sizeof(wep->wePart1)/2; --i >= 0;) { 492 if (--unlen < 0) { 493 if (!*cp++ && !*cp) 494 return chksum; 495 return -1; 496 } 497 if (u2l[*cp++] != u2l[*un++] || *cp++) 498 return -1; 499 } 500 for (cp = wep->wePart2, i = sizeof(wep->wePart2)/2; --i >= 0;) { 501 if (--unlen < 0) { 502 if (!*cp++ && !*cp) 503 return chksum; 504 return -1; 505 } 506 if (u2l[*cp++] != u2l[*un++] || *cp++) 507 return -1; 508 } 509 for (cp = wep->wePart3, i = sizeof(wep->wePart3)/2; --i >= 0;) { 510 if (--unlen < 0) { 511 if (!*cp++ && !*cp) 512 return chksum; 513 return -1; 514 } 515 if (u2l[*cp++] != u2l[*un++] || *cp++) 516 return -1; 517 } 518 return chksum; 519 } 520 521 /* 522 * Compute the checksum of a DOS filename for Win95 use 523 */ 524 u_int8_t 525 winChksum(u_int8_t *name) 526 { 527 int i; 528 u_int8_t s; 529 530 for (s = 0, i = 11; --i >= 0; s += *name++) 531 s = (s << 7)|(s >> 1); 532 return s; 533 } 534 535 /* 536 * Determine the number of slots necessary for Win95 names 537 */ 538 int 539 winSlotCnt(u_char *un, int unlen) 540 { 541 for (un += unlen; unlen > 0; unlen--) 542 if (*--un != ' ' && *un != '.') 543 break; 544 if (unlen > WIN_MAXLEN) 545 return 0; 546 return howmany(unlen, WIN_CHARS); 547 } 548