1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2019 Google LLC 5 * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank 6 * Copyright (c) 1995 Martin Husemann 7 * Some structure declaration borrowed from Paul Popelka 8 * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference. 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __RCSID("$NetBSD: dir.c,v 1.20 2006/06/05 16:51:18 christos Exp $"); 35 static const char rcsid[] = 36 "$FreeBSD$"; 37 #endif /* not lint */ 38 39 #include <assert.h> 40 #include <inttypes.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <ctype.h> 45 #include <unistd.h> 46 #include <time.h> 47 48 #include <sys/param.h> 49 50 #include "ext.h" 51 #include "fsutil.h" 52 53 #define SLOT_EMPTY 0x00 /* slot has never been used */ 54 #define SLOT_E5 0x05 /* the real value is 0xe5 */ 55 #define SLOT_DELETED 0xe5 /* file in this slot deleted */ 56 57 #define ATTR_NORMAL 0x00 /* normal file */ 58 #define ATTR_READONLY 0x01 /* file is readonly */ 59 #define ATTR_HIDDEN 0x02 /* file is hidden */ 60 #define ATTR_SYSTEM 0x04 /* file is a system file */ 61 #define ATTR_VOLUME 0x08 /* entry is a volume label */ 62 #define ATTR_DIRECTORY 0x10 /* entry is a directory name */ 63 #define ATTR_ARCHIVE 0x20 /* file is new or modified */ 64 65 #define ATTR_WIN95 0x0f /* long name record */ 66 67 /* 68 * This is the format of the contents of the deTime field in the direntry 69 * structure. 70 * We don't use bitfields because we don't know how compilers for 71 * arbitrary machines will lay them out. 72 */ 73 #define DT_2SECONDS_MASK 0x1F /* seconds divided by 2 */ 74 #define DT_2SECONDS_SHIFT 0 75 #define DT_MINUTES_MASK 0x7E0 /* minutes */ 76 #define DT_MINUTES_SHIFT 5 77 #define DT_HOURS_MASK 0xF800 /* hours */ 78 #define DT_HOURS_SHIFT 11 79 80 /* 81 * This is the format of the contents of the deDate field in the direntry 82 * structure. 83 */ 84 #define DD_DAY_MASK 0x1F /* day of month */ 85 #define DD_DAY_SHIFT 0 86 #define DD_MONTH_MASK 0x1E0 /* month */ 87 #define DD_MONTH_SHIFT 5 88 #define DD_YEAR_MASK 0xFE00 /* year - 1980 */ 89 #define DD_YEAR_SHIFT 9 90 91 92 /* dir.c */ 93 static struct dosDirEntry *newDosDirEntry(void); 94 static void freeDosDirEntry(struct dosDirEntry *); 95 static struct dirTodoNode *newDirTodo(void); 96 static void freeDirTodo(struct dirTodoNode *); 97 static char *fullpath(struct dosDirEntry *); 98 static u_char calcShortSum(u_char *); 99 static int delete(struct fat_descriptor *, cl_t, int, cl_t, int, int); 100 static int removede(struct fat_descriptor *, u_char *, u_char *, 101 cl_t, cl_t, cl_t, char *, int); 102 static int checksize(struct fat_descriptor *, u_char *, struct dosDirEntry *); 103 static int readDosDirSection(struct fat_descriptor *, struct dosDirEntry *); 104 105 /* 106 * Manage free dosDirEntry structures. 107 */ 108 static struct dosDirEntry *freede; 109 110 static struct dosDirEntry * 111 newDosDirEntry(void) 112 { 113 struct dosDirEntry *de; 114 115 if (!(de = freede)) { 116 if (!(de = malloc(sizeof *de))) 117 return (NULL); 118 } else 119 freede = de->next; 120 return de; 121 } 122 123 static void 124 freeDosDirEntry(struct dosDirEntry *de) 125 { 126 de->next = freede; 127 freede = de; 128 } 129 130 /* 131 * The same for dirTodoNode structures. 132 */ 133 static struct dirTodoNode *freedt; 134 135 static struct dirTodoNode * 136 newDirTodo(void) 137 { 138 struct dirTodoNode *dt; 139 140 if (!(dt = freedt)) { 141 if (!(dt = malloc(sizeof *dt))) 142 return 0; 143 } else 144 freedt = dt->next; 145 return dt; 146 } 147 148 static void 149 freeDirTodo(struct dirTodoNode *dt) 150 { 151 dt->next = freedt; 152 freedt = dt; 153 } 154 155 /* 156 * The stack of unread directories 157 */ 158 static struct dirTodoNode *pendingDirectories = NULL; 159 160 /* 161 * Return the full pathname for a directory entry. 162 */ 163 static char * 164 fullpath(struct dosDirEntry *dir) 165 { 166 static char namebuf[MAXPATHLEN + 1]; 167 char *cp, *np; 168 int nl; 169 170 cp = namebuf + sizeof namebuf; 171 *--cp = '\0'; 172 173 for(;;) { 174 np = dir->lname[0] ? dir->lname : dir->name; 175 nl = strlen(np); 176 if (cp <= namebuf + 1 + nl) { 177 *--cp = '?'; 178 break; 179 } 180 cp -= nl; 181 memcpy(cp, np, nl); 182 dir = dir->parent; 183 if (!dir) 184 break; 185 *--cp = '/'; 186 } 187 188 return cp; 189 } 190 191 /* 192 * Calculate a checksum over an 8.3 alias name 193 */ 194 static inline u_char 195 calcShortSum(u_char *p) 196 { 197 u_char sum = 0; 198 int i; 199 200 for (i = 0; i < 11; i++) { 201 sum = (sum << 7)|(sum >> 1); /* rotate right */ 202 sum += p[i]; 203 } 204 205 return sum; 206 } 207 208 /* 209 * Global variables temporarily used during a directory scan 210 */ 211 static char longName[DOSLONGNAMELEN] = ""; 212 static u_char *buffer = NULL; 213 static u_char *delbuf = NULL; 214 215 static struct dosDirEntry *rootDir; 216 static struct dosDirEntry *lostDir; 217 218 /* 219 * Init internal state for a new directory scan. 220 */ 221 int 222 resetDosDirSection(struct fat_descriptor *fat) 223 { 224 int rootdir_size, cluster_size; 225 int ret = FSOK; 226 size_t len; 227 struct bootblock *boot; 228 229 boot = fat_get_boot(fat); 230 231 rootdir_size = boot->bpbRootDirEnts * 32; 232 cluster_size = boot->bpbSecPerClust * boot->bpbBytesPerSec; 233 234 if ((buffer = malloc(len = MAX(rootdir_size, cluster_size))) == NULL) { 235 perr("No space for directory buffer (%zu)", len); 236 return FSFATAL; 237 } 238 239 if ((delbuf = malloc(len = cluster_size)) == NULL) { 240 free(buffer); 241 perr("No space for directory delbuf (%zu)", len); 242 return FSFATAL; 243 } 244 245 if ((rootDir = newDosDirEntry()) == NULL) { 246 free(buffer); 247 free(delbuf); 248 perr("No space for directory entry"); 249 return FSFATAL; 250 } 251 252 memset(rootDir, 0, sizeof *rootDir); 253 if (boot->flags & FAT32) { 254 if (!fat_is_cl_head(fat, boot->bpbRootClust)) { 255 pfatal("Root directory doesn't start a cluster chain"); 256 return FSFATAL; 257 } 258 rootDir->head = boot->bpbRootClust; 259 } 260 261 return ret; 262 } 263 264 /* 265 * Cleanup after a directory scan 266 */ 267 void 268 finishDosDirSection(void) 269 { 270 struct dirTodoNode *p, *np; 271 struct dosDirEntry *d, *nd; 272 273 for (p = pendingDirectories; p; p = np) { 274 np = p->next; 275 freeDirTodo(p); 276 } 277 pendingDirectories = NULL; 278 for (d = rootDir; d; d = nd) { 279 if ((nd = d->child) != NULL) { 280 d->child = 0; 281 continue; 282 } 283 if (!(nd = d->next)) 284 nd = d->parent; 285 freeDosDirEntry(d); 286 } 287 rootDir = lostDir = NULL; 288 free(buffer); 289 free(delbuf); 290 buffer = NULL; 291 delbuf = NULL; 292 } 293 294 /* 295 * Delete directory entries between startcl, startoff and endcl, endoff. 296 */ 297 static int 298 delete(struct fat_descriptor *fat, cl_t startcl, 299 int startoff, cl_t endcl, int endoff, int notlast) 300 { 301 u_char *s, *e; 302 off_t off; 303 int clsz, fd; 304 struct bootblock *boot; 305 306 boot = fat_get_boot(fat); 307 fd = fat_get_fd(fat); 308 clsz = boot->bpbSecPerClust * boot->bpbBytesPerSec; 309 310 s = delbuf + startoff; 311 e = delbuf + clsz; 312 while (fat_is_valid_cl(fat, startcl)) { 313 if (startcl == endcl) { 314 if (notlast) 315 break; 316 e = delbuf + endoff; 317 } 318 off = (startcl - CLUST_FIRST) * boot->bpbSecPerClust + boot->FirstCluster; 319 320 off *= boot->bpbBytesPerSec; 321 if (lseek(fd, off, SEEK_SET) != off) { 322 perr("Unable to lseek to %" PRId64, off); 323 return FSFATAL; 324 } 325 if (read(fd, delbuf, clsz) != clsz) { 326 perr("Unable to read directory"); 327 return FSFATAL; 328 } 329 while (s < e) { 330 *s = SLOT_DELETED; 331 s += 32; 332 } 333 if (lseek(fd, off, SEEK_SET) != off) { 334 perr("Unable to lseek to %" PRId64, off); 335 return FSFATAL; 336 } 337 if (write(fd, delbuf, clsz) != clsz) { 338 perr("Unable to write directory"); 339 return FSFATAL; 340 } 341 if (startcl == endcl) 342 break; 343 startcl = fat_get_cl_next(fat, startcl); 344 s = delbuf; 345 } 346 return FSOK; 347 } 348 349 static int 350 removede(struct fat_descriptor *fat, u_char *start, 351 u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, 352 char *path, int type) 353 { 354 switch (type) { 355 case 0: 356 pwarn("Invalid long filename entry for %s\n", path); 357 break; 358 case 1: 359 pwarn("Invalid long filename entry at end of directory %s\n", 360 path); 361 break; 362 case 2: 363 pwarn("Invalid long filename entry for volume label\n"); 364 break; 365 } 366 if (ask(0, "Remove")) { 367 if (startcl != curcl) { 368 if (delete(fat, 369 startcl, start - buffer, 370 endcl, end - buffer, 371 endcl == curcl) == FSFATAL) 372 return FSFATAL; 373 start = buffer; 374 } 375 /* startcl is < CLUST_FIRST for !FAT32 root */ 376 if ((endcl == curcl) || (startcl < CLUST_FIRST)) 377 for (; start < end; start += 32) 378 *start = SLOT_DELETED; 379 return FSDIRMOD; 380 } 381 return FSERROR; 382 } 383 384 /* 385 * Check an in-memory file entry 386 */ 387 static int 388 checksize(struct fat_descriptor *fat, u_char *p, struct dosDirEntry *dir) 389 { 390 int ret = FSOK; 391 size_t physicalSize; 392 struct bootblock *boot; 393 394 boot = fat_get_boot(fat); 395 396 /* 397 * Check size on ordinary files 398 */ 399 if (dir->head == CLUST_FREE) { 400 physicalSize = 0; 401 } else { 402 if (!fat_is_valid_cl(fat, dir->head)) 403 return FSERROR; 404 ret = checkchain(fat, dir->head, &physicalSize); 405 /* 406 * Upon return, physicalSize would hold the chain length 407 * that checkchain() was able to validate, but if the user 408 * refused the proposed repair, it would be unsafe to 409 * proceed with directory entry fix, so bail out in that 410 * case. 411 */ 412 if (ret == FSERROR) { 413 return (FSERROR); 414 } 415 physicalSize *= boot->ClusterSize; 416 } 417 if (physicalSize < dir->size) { 418 pwarn("size of %s is %u, should at most be %zu\n", 419 fullpath(dir), dir->size, physicalSize); 420 if (ask(1, "Truncate")) { 421 dir->size = physicalSize; 422 p[28] = (u_char)physicalSize; 423 p[29] = (u_char)(physicalSize >> 8); 424 p[30] = (u_char)(physicalSize >> 16); 425 p[31] = (u_char)(physicalSize >> 24); 426 return FSDIRMOD; 427 } else 428 return FSERROR; 429 } else if (physicalSize - dir->size >= boot->ClusterSize) { 430 pwarn("%s has too many clusters allocated\n", 431 fullpath(dir)); 432 if (ask(1, "Drop superfluous clusters")) { 433 cl_t cl; 434 u_int32_t sz, len; 435 436 for (cl = dir->head, len = sz = 0; 437 (sz += boot->ClusterSize) < dir->size; len++) 438 cl = fat_get_cl_next(fat, cl); 439 clearchain(fat, fat_get_cl_next(fat, cl)); 440 ret = fat_set_cl_next(fat, cl, CLUST_EOF); 441 return (FSFATMOD | ret); 442 } else 443 return FSERROR; 444 } 445 return FSOK; 446 } 447 448 static const u_char dot_name[11] = ". "; 449 static const u_char dotdot_name[11] = ".. "; 450 451 /* 452 * Basic sanity check if the subdirectory have good '.' and '..' entries, 453 * and they are directory entries. Further sanity checks are performed 454 * when we traverse into it. 455 */ 456 static int 457 check_subdirectory(struct fat_descriptor *fat, struct dosDirEntry *dir) 458 { 459 u_char *buf, *cp; 460 off_t off; 461 cl_t cl; 462 int retval = FSOK; 463 int fd; 464 struct bootblock *boot; 465 466 boot = fat_get_boot(fat); 467 fd = fat_get_fd(fat); 468 469 cl = dir->head; 470 if (dir->parent && !fat_is_valid_cl(fat, cl)) { 471 return FSERROR; 472 } 473 474 if (!(boot->flags & FAT32) && !dir->parent) { 475 off = boot->bpbResSectors + boot->bpbFATs * 476 boot->FATsecs; 477 } else { 478 off = (cl - CLUST_FIRST) * boot->bpbSecPerClust + boot->FirstCluster; 479 } 480 481 /* 482 * We only need to check the first two entries of the directory, 483 * which is found in the first sector of the directory entry, 484 * so read in only the first sector. 485 */ 486 buf = malloc(boot->bpbBytesPerSec); 487 if (buf == NULL) { 488 perr("No space for directory buffer (%u)", 489 boot->bpbBytesPerSec); 490 return FSFATAL; 491 } 492 493 off *= boot->bpbBytesPerSec; 494 if (lseek(fd, off, SEEK_SET) != off || 495 read(fd, buf, boot->bpbBytesPerSec) != (ssize_t)boot->bpbBytesPerSec) { 496 perr("Unable to read directory"); 497 free(buf); 498 return FSFATAL; 499 } 500 501 /* 502 * Both `.' and `..' must be present and be the first two entries 503 * and be ATTR_DIRECTORY of a valid subdirectory. 504 */ 505 cp = buf; 506 if (memcmp(cp, dot_name, sizeof(dot_name)) != 0 || 507 (cp[11] & ATTR_DIRECTORY) != ATTR_DIRECTORY) { 508 pwarn("%s: Incorrect `.' for %s.\n", __func__, dir->name); 509 retval |= FSERROR; 510 } 511 cp += 32; 512 if (memcmp(cp, dotdot_name, sizeof(dotdot_name)) != 0 || 513 (cp[11] & ATTR_DIRECTORY) != ATTR_DIRECTORY) { 514 pwarn("%s: Incorrect `..' for %s. \n", __func__, dir->name); 515 retval |= FSERROR; 516 } 517 518 free(buf); 519 return retval; 520 } 521 522 /* 523 * Read a directory and 524 * - resolve long name records 525 * - enter file and directory records into the parent's list 526 * - push directories onto the todo-stack 527 */ 528 static int 529 readDosDirSection(struct fat_descriptor *fat, struct dosDirEntry *dir) 530 { 531 struct bootblock *boot; 532 struct dosDirEntry dirent, *d; 533 u_char *p, *vallfn, *invlfn, *empty; 534 off_t off; 535 int fd, i, j, k, iosize, entries; 536 bool is_legacyroot; 537 cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0; 538 char *t; 539 u_int lidx = 0; 540 int shortSum; 541 int mod = FSOK; 542 size_t dirclusters; 543 #define THISMOD 0x8000 /* Only used within this routine */ 544 545 boot = fat_get_boot(fat); 546 fd = fat_get_fd(fat); 547 548 cl = dir->head; 549 if (dir->parent && (!fat_is_valid_cl(fat, cl))) { 550 /* 551 * Already handled somewhere else. 552 */ 553 return FSOK; 554 } 555 shortSum = -1; 556 vallfn = invlfn = empty = NULL; 557 558 /* 559 * If we are checking the legacy root (for FAT12/FAT16), 560 * we will operate on the whole directory; otherwise, we 561 * will operate on one cluster at a time, and also take 562 * this opportunity to examine the chain. 563 * 564 * Derive how many entries we are going to encounter from 565 * the I/O size. 566 */ 567 is_legacyroot = (dir->parent == NULL && !(boot->flags & FAT32)); 568 if (is_legacyroot) { 569 iosize = boot->bpbRootDirEnts * 32; 570 entries = boot->bpbRootDirEnts; 571 } else { 572 iosize = boot->bpbSecPerClust * boot->bpbBytesPerSec; 573 entries = iosize / 32; 574 mod |= checkchain(fat, dir->head, &dirclusters); 575 } 576 577 do { 578 if (is_legacyroot) { 579 /* 580 * Special case for FAT12/FAT16 root -- read 581 * in the whole root directory. 582 */ 583 off = boot->bpbResSectors + boot->bpbFATs * 584 boot->FATsecs; 585 } else { 586 /* 587 * Otherwise, read in a cluster of the 588 * directory. 589 */ 590 off = (cl - CLUST_FIRST) * boot->bpbSecPerClust + boot->FirstCluster; 591 } 592 593 off *= boot->bpbBytesPerSec; 594 if (lseek(fd, off, SEEK_SET) != off || 595 read(fd, buffer, iosize) != iosize) { 596 perr("Unable to read directory"); 597 return FSFATAL; 598 } 599 600 for (p = buffer, i = 0; i < entries; i++, p += 32) { 601 if (dir->fsckflags & DIREMPWARN) { 602 *p = SLOT_EMPTY; 603 continue; 604 } 605 606 if (*p == SLOT_EMPTY || *p == SLOT_DELETED) { 607 if (*p == SLOT_EMPTY) { 608 dir->fsckflags |= DIREMPTY; 609 empty = p; 610 empcl = cl; 611 } 612 continue; 613 } 614 615 if (dir->fsckflags & DIREMPTY) { 616 if (!(dir->fsckflags & DIREMPWARN)) { 617 pwarn("%s has entries after end of directory\n", 618 fullpath(dir)); 619 if (ask(1, "Extend")) { 620 u_char *q; 621 622 dir->fsckflags &= ~DIREMPTY; 623 if (delete(fat, 624 empcl, empty - buffer, 625 cl, p - buffer, 1) == FSFATAL) 626 return FSFATAL; 627 q = ((empcl == cl) ? empty : buffer); 628 assert(q != NULL); 629 for (; q < p; q += 32) 630 *q = SLOT_DELETED; 631 mod |= THISMOD|FSDIRMOD; 632 } else if (ask(0, "Truncate")) 633 dir->fsckflags |= DIREMPWARN; 634 } 635 if (dir->fsckflags & DIREMPWARN) { 636 *p = SLOT_DELETED; 637 mod |= THISMOD|FSDIRMOD; 638 continue; 639 } else if (dir->fsckflags & DIREMPTY) 640 mod |= FSERROR; 641 empty = NULL; 642 } 643 644 if (p[11] == ATTR_WIN95) { 645 if (*p & LRFIRST) { 646 if (shortSum != -1) { 647 if (!invlfn) { 648 invlfn = vallfn; 649 invcl = valcl; 650 } 651 } 652 memset(longName, 0, sizeof longName); 653 shortSum = p[13]; 654 vallfn = p; 655 valcl = cl; 656 } else if (shortSum != p[13] 657 || lidx != (*p & LRNOMASK)) { 658 if (!invlfn) { 659 invlfn = vallfn; 660 invcl = valcl; 661 } 662 if (!invlfn) { 663 invlfn = p; 664 invcl = cl; 665 } 666 vallfn = NULL; 667 } 668 lidx = *p & LRNOMASK; 669 if (lidx == 0) { 670 pwarn("invalid long name\n"); 671 if (!invlfn) { 672 invlfn = vallfn; 673 invcl = valcl; 674 } 675 vallfn = NULL; 676 continue; 677 } 678 t = longName + --lidx * 13; 679 for (k = 1; k < 11 && t < longName + 680 sizeof(longName); k += 2) { 681 if (!p[k] && !p[k + 1]) 682 break; 683 *t++ = p[k]; 684 /* 685 * Warn about those unusable chars in msdosfs here? XXX 686 */ 687 if (p[k + 1]) 688 t[-1] = '?'; 689 } 690 if (k >= 11) 691 for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) { 692 if (!p[k] && !p[k + 1]) 693 break; 694 *t++ = p[k]; 695 if (p[k + 1]) 696 t[-1] = '?'; 697 } 698 if (k >= 26) 699 for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) { 700 if (!p[k] && !p[k + 1]) 701 break; 702 *t++ = p[k]; 703 if (p[k + 1]) 704 t[-1] = '?'; 705 } 706 if (t >= longName + sizeof(longName)) { 707 pwarn("long filename too long\n"); 708 if (!invlfn) { 709 invlfn = vallfn; 710 invcl = valcl; 711 } 712 vallfn = NULL; 713 } 714 if (p[26] | (p[27] << 8)) { 715 pwarn("long filename record cluster start != 0\n"); 716 if (!invlfn) { 717 invlfn = vallfn; 718 invcl = cl; 719 } 720 vallfn = NULL; 721 } 722 continue; /* long records don't carry further 723 * information */ 724 } 725 726 /* 727 * This is a standard msdosfs directory entry. 728 */ 729 memset(&dirent, 0, sizeof dirent); 730 731 /* 732 * it's a short name record, but we need to know 733 * more, so get the flags first. 734 */ 735 dirent.flags = p[11]; 736 737 /* 738 * Translate from 850 to ISO here XXX 739 */ 740 for (j = 0; j < 8; j++) 741 dirent.name[j] = p[j]; 742 dirent.name[8] = '\0'; 743 for (k = 7; k >= 0 && dirent.name[k] == ' '; k--) 744 dirent.name[k] = '\0'; 745 if (k < 0 || dirent.name[k] != '\0') 746 k++; 747 if (dirent.name[0] == SLOT_E5) 748 dirent.name[0] = 0xe5; 749 750 if (dirent.flags & ATTR_VOLUME) { 751 if (vallfn || invlfn) { 752 mod |= removede(fat, 753 invlfn ? invlfn : vallfn, p, 754 invlfn ? invcl : valcl, -1, 0, 755 fullpath(dir), 2); 756 vallfn = NULL; 757 invlfn = NULL; 758 } 759 continue; 760 } 761 762 if (p[8] != ' ') 763 dirent.name[k++] = '.'; 764 for (j = 0; j < 3; j++) 765 dirent.name[k++] = p[j+8]; 766 dirent.name[k] = '\0'; 767 for (k--; k >= 0 && dirent.name[k] == ' '; k--) 768 dirent.name[k] = '\0'; 769 770 if (vallfn && shortSum != calcShortSum(p)) { 771 if (!invlfn) { 772 invlfn = vallfn; 773 invcl = valcl; 774 } 775 vallfn = NULL; 776 } 777 dirent.head = p[26] | (p[27] << 8); 778 if (boot->ClustMask == CLUST32_MASK) 779 dirent.head |= (p[20] << 16) | (p[21] << 24); 780 dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24); 781 if (vallfn) { 782 strlcpy(dirent.lname, longName, 783 sizeof(dirent.lname)); 784 longName[0] = '\0'; 785 shortSum = -1; 786 } 787 788 dirent.parent = dir; 789 dirent.next = dir->child; 790 791 if (invlfn) { 792 mod |= k = removede(fat, 793 invlfn, vallfn ? vallfn : p, 794 invcl, vallfn ? valcl : cl, cl, 795 fullpath(&dirent), 0); 796 if (mod & FSFATAL) 797 return FSFATAL; 798 if (vallfn 799 ? (valcl == cl && vallfn != buffer) 800 : p != buffer) 801 if (k & FSDIRMOD) 802 mod |= THISMOD; 803 } 804 805 vallfn = NULL; /* not used any longer */ 806 invlfn = NULL; 807 808 /* 809 * Check if the directory entry is sane. 810 * 811 * '.' and '..' are skipped, their sanity is 812 * checked somewhere else. 813 * 814 * For everything else, check if we have a new, 815 * valid cluster chain (beginning of a file or 816 * directory that was never previously claimed 817 * by another file) when it's a non-empty file 818 * or a directory. The sanity of the cluster 819 * chain is checked at a later time when we 820 * traverse into the directory, or examine the 821 * file's directory entry. 822 * 823 * The only possible fix is to delete the entry 824 * if it's a directory; for file, we have to 825 * truncate the size to 0. 826 */ 827 if (!(dirent.flags & ATTR_DIRECTORY) || 828 (strcmp(dirent.name, ".") != 0 && 829 strcmp(dirent.name, "..") != 0)) { 830 if ((dirent.size != 0 || (dirent.flags & ATTR_DIRECTORY)) && 831 ((!fat_is_valid_cl(fat, dirent.head) || 832 !fat_is_cl_head(fat, dirent.head)))) { 833 if (!fat_is_valid_cl(fat, dirent.head)) { 834 pwarn("%s starts with cluster out of range(%u)\n", 835 fullpath(&dirent), 836 dirent.head); 837 } else { 838 pwarn("%s doesn't start a new cluster chain\n", 839 fullpath(&dirent)); 840 } 841 842 if (dirent.flags & ATTR_DIRECTORY) { 843 if (ask(0, "Remove")) { 844 *p = SLOT_DELETED; 845 mod |= THISMOD|FSDIRMOD; 846 } else 847 mod |= FSERROR; 848 continue; 849 } else { 850 if (ask(1, "Truncate")) { 851 p[28] = p[29] = p[30] = p[31] = 0; 852 p[26] = p[27] = 0; 853 if (boot->ClustMask == CLUST32_MASK) 854 p[20] = p[21] = 0; 855 dirent.size = 0; 856 dirent.head = 0; 857 mod |= THISMOD|FSDIRMOD; 858 } else 859 mod |= FSERROR; 860 } 861 } 862 } 863 if (dirent.flags & ATTR_DIRECTORY) { 864 /* 865 * gather more info for directories 866 */ 867 struct dirTodoNode *n; 868 869 if (dirent.size) { 870 pwarn("Directory %s has size != 0\n", 871 fullpath(&dirent)); 872 if (ask(1, "Correct")) { 873 p[28] = p[29] = p[30] = p[31] = 0; 874 dirent.size = 0; 875 mod |= THISMOD|FSDIRMOD; 876 } else 877 mod |= FSERROR; 878 } 879 /* 880 * handle `.' and `..' specially 881 */ 882 if (strcmp(dirent.name, ".") == 0) { 883 if (dirent.head != dir->head) { 884 pwarn("`.' entry in %s has incorrect start cluster\n", 885 fullpath(dir)); 886 if (ask(1, "Correct")) { 887 dirent.head = dir->head; 888 p[26] = (u_char)dirent.head; 889 p[27] = (u_char)(dirent.head >> 8); 890 if (boot->ClustMask == CLUST32_MASK) { 891 p[20] = (u_char)(dirent.head >> 16); 892 p[21] = (u_char)(dirent.head >> 24); 893 } 894 mod |= THISMOD|FSDIRMOD; 895 } else 896 mod |= FSERROR; 897 } 898 continue; 899 } else if (strcmp(dirent.name, "..") == 0) { 900 if (dir->parent) { /* XXX */ 901 if (!dir->parent->parent) { 902 if (dirent.head) { 903 pwarn("`..' entry in %s has non-zero start cluster\n", 904 fullpath(dir)); 905 if (ask(1, "Correct")) { 906 dirent.head = 0; 907 p[26] = p[27] = 0; 908 if (boot->ClustMask == CLUST32_MASK) 909 p[20] = p[21] = 0; 910 mod |= THISMOD|FSDIRMOD; 911 } else 912 mod |= FSERROR; 913 } 914 } else if (dirent.head != dir->parent->head) { 915 pwarn("`..' entry in %s has incorrect start cluster\n", 916 fullpath(dir)); 917 if (ask(1, "Correct")) { 918 dirent.head = dir->parent->head; 919 p[26] = (u_char)dirent.head; 920 p[27] = (u_char)(dirent.head >> 8); 921 if (boot->ClustMask == CLUST32_MASK) { 922 p[20] = (u_char)(dirent.head >> 16); 923 p[21] = (u_char)(dirent.head >> 24); 924 } 925 mod |= THISMOD|FSDIRMOD; 926 } else 927 mod |= FSERROR; 928 } 929 } 930 continue; 931 } else { 932 /* 933 * Only one directory entry can point 934 * to dir->head, it's '.'. 935 */ 936 if (dirent.head == dir->head) { 937 pwarn("%s entry in %s has incorrect start cluster\n", 938 dirent.name, fullpath(dir)); 939 if (ask(1, "Remove")) { 940 *p = SLOT_DELETED; 941 mod |= THISMOD|FSDIRMOD; 942 } else 943 mod |= FSERROR; 944 continue; 945 } else if ((check_subdirectory(fat, 946 &dirent) & FSERROR) == FSERROR) { 947 /* 948 * A subdirectory should have 949 * a dot (.) entry and a dot-dot 950 * (..) entry of ATTR_DIRECTORY, 951 * we will inspect further when 952 * traversing into it. 953 */ 954 if (ask(1, "Remove")) { 955 *p = SLOT_DELETED; 956 mod |= THISMOD|FSDIRMOD; 957 } else 958 mod |= FSERROR; 959 continue; 960 } 961 } 962 963 /* create directory tree node */ 964 if (!(d = newDosDirEntry())) { 965 perr("No space for directory"); 966 return FSFATAL; 967 } 968 memcpy(d, &dirent, sizeof(struct dosDirEntry)); 969 /* link it into the tree */ 970 dir->child = d; 971 972 /* Enter this directory into the todo list */ 973 if (!(n = newDirTodo())) { 974 perr("No space for todo list"); 975 return FSFATAL; 976 } 977 n->next = pendingDirectories; 978 n->dir = d; 979 pendingDirectories = n; 980 } else { 981 mod |= k = checksize(fat, p, &dirent); 982 if (k & FSDIRMOD) 983 mod |= THISMOD; 984 } 985 boot->NumFiles++; 986 } 987 988 if (is_legacyroot) { 989 /* 990 * Don't bother to write back right now because 991 * we may continue to make modification to the 992 * non-FAT32 root directory below. 993 */ 994 break; 995 } else if (mod & THISMOD) { 996 if (lseek(fd, off, SEEK_SET) != off 997 || write(fd, buffer, iosize) != iosize) { 998 perr("Unable to write directory"); 999 return FSFATAL; 1000 } 1001 mod &= ~THISMOD; 1002 } 1003 } while (fat_is_valid_cl(fat, (cl = fat_get_cl_next(fat, cl)))); 1004 if (invlfn || vallfn) 1005 mod |= removede(fat, 1006 invlfn ? invlfn : vallfn, p, 1007 invlfn ? invcl : valcl, -1, 0, 1008 fullpath(dir), 1); 1009 1010 /* 1011 * The root directory of non-FAT32 filesystems is in a special 1012 * area and may have been modified above removede() without 1013 * being written out. 1014 */ 1015 if ((mod & FSDIRMOD) && is_legacyroot) { 1016 if (lseek(fd, off, SEEK_SET) != off 1017 || write(fd, buffer, iosize) != iosize) { 1018 perr("Unable to write directory"); 1019 return FSFATAL; 1020 } 1021 mod &= ~THISMOD; 1022 } 1023 return mod & ~THISMOD; 1024 } 1025 1026 int 1027 handleDirTree(struct fat_descriptor *fat) 1028 { 1029 int mod; 1030 1031 mod = readDosDirSection(fat, rootDir); 1032 if (mod & FSFATAL) 1033 return FSFATAL; 1034 1035 /* 1036 * process the directory todo list 1037 */ 1038 while (pendingDirectories) { 1039 struct dosDirEntry *dir = pendingDirectories->dir; 1040 struct dirTodoNode *n = pendingDirectories->next; 1041 1042 /* 1043 * remove TODO entry now, the list might change during 1044 * directory reads 1045 */ 1046 freeDirTodo(pendingDirectories); 1047 pendingDirectories = n; 1048 1049 /* 1050 * handle subdirectory 1051 */ 1052 mod |= readDosDirSection(fat, dir); 1053 if (mod & FSFATAL) 1054 return FSFATAL; 1055 } 1056 1057 return mod; 1058 } 1059 1060 /* 1061 * Try to reconnect a FAT chain into dir 1062 */ 1063 static u_char *lfbuf; 1064 static cl_t lfcl; 1065 static off_t lfoff; 1066 1067 int 1068 reconnect(struct fat_descriptor *fat, cl_t head, size_t length) 1069 { 1070 struct bootblock *boot = fat_get_boot(fat); 1071 struct dosDirEntry d; 1072 int len, dosfs; 1073 u_char *p; 1074 1075 dosfs = fat_get_fd(fat); 1076 1077 if (!ask(1, "Reconnect")) 1078 return FSERROR; 1079 1080 if (!lostDir) { 1081 for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) { 1082 if (!strcmp(lostDir->name, LOSTDIR)) 1083 break; 1084 } 1085 if (!lostDir) { /* Create LOSTDIR? XXX */ 1086 pwarn("No %s directory\n", LOSTDIR); 1087 return FSERROR; 1088 } 1089 } 1090 if (!lfbuf) { 1091 lfbuf = malloc(boot->ClusterSize); 1092 if (!lfbuf) { 1093 perr("No space for buffer"); 1094 return FSFATAL; 1095 } 1096 p = NULL; 1097 } else 1098 p = lfbuf; 1099 while (1) { 1100 if (p) 1101 for (; p < lfbuf + boot->ClusterSize; p += 32) 1102 if (*p == SLOT_EMPTY 1103 || *p == SLOT_DELETED) 1104 break; 1105 if (p && p < lfbuf + boot->ClusterSize) 1106 break; 1107 lfcl = p ? fat_get_cl_next(fat, lfcl) : lostDir->head; 1108 if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) { 1109 /* Extend LOSTDIR? XXX */ 1110 pwarn("No space in %s\n", LOSTDIR); 1111 lfcl = (lostDir->head < boot->NumClusters) ? lostDir->head : 0; 1112 return FSERROR; 1113 } 1114 lfoff = (lfcl - CLUST_FIRST) * boot->ClusterSize 1115 + boot->FirstCluster * boot->bpbBytesPerSec; 1116 1117 if (lseek(dosfs, lfoff, SEEK_SET) != lfoff 1118 || (size_t)read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) { 1119 perr("could not read LOST.DIR"); 1120 return FSFATAL; 1121 } 1122 p = lfbuf; 1123 } 1124 1125 boot->NumFiles++; 1126 /* Ensure uniqueness of entry here! XXX */ 1127 memset(&d, 0, sizeof d); 1128 /* worst case -1 = 4294967295, 10 digits */ 1129 len = snprintf(d.name, sizeof(d.name), "%u", head); 1130 d.flags = 0; 1131 d.head = head; 1132 d.size = length * boot->ClusterSize; 1133 1134 memcpy(p, d.name, len); 1135 memset(p + len, ' ', 11 - len); 1136 memset(p + 11, 0, 32 - 11); 1137 p[26] = (u_char)d.head; 1138 p[27] = (u_char)(d.head >> 8); 1139 if (boot->ClustMask == CLUST32_MASK) { 1140 p[20] = (u_char)(d.head >> 16); 1141 p[21] = (u_char)(d.head >> 24); 1142 } 1143 p[28] = (u_char)d.size; 1144 p[29] = (u_char)(d.size >> 8); 1145 p[30] = (u_char)(d.size >> 16); 1146 p[31] = (u_char)(d.size >> 24); 1147 if (lseek(dosfs, lfoff, SEEK_SET) != lfoff 1148 || (size_t)write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) { 1149 perr("could not write LOST.DIR"); 1150 return FSFATAL; 1151 } 1152 return FSDIRMOD; 1153 } 1154 1155 void 1156 finishlf(void) 1157 { 1158 if (lfbuf) 1159 free(lfbuf); 1160 lfbuf = NULL; 1161 } 1162