xref: /netbsd/sbin/fsck_msdos/dir.c (revision 639b3062)
1 /*	$NetBSD: dir.c,v 1.29 2017/04/28 11:33:00 christos Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
5  * Copyright (c) 1995 Martin Husemann
6  * Some structure declaration borrowed from Paul Popelka
7  * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 
31 #include <sys/cdefs.h>
32 #ifndef lint
33 __RCSID("$NetBSD: dir.c,v 1.29 2017/04/28 11:33:00 christos Exp $");
34 #endif /* not lint */
35 
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <ctype.h>
40 #include <unistd.h>
41 #include <assert.h>
42 #include <time.h>
43 
44 #include <sys/param.h>
45 
46 #include "ext.h"
47 #include "fsutil.h"
48 
49 #define	SLOT_EMPTY	0x00		/* slot has never been used */
50 #define	SLOT_E5		0x05		/* the real value is 0xe5 */
51 #define	SLOT_DELETED	0xe5		/* file in this slot deleted */
52 
53 #define	ATTR_NORMAL	0x00		/* normal file */
54 #define	ATTR_READONLY	0x01		/* file is readonly */
55 #define	ATTR_HIDDEN	0x02		/* file is hidden */
56 #define	ATTR_SYSTEM	0x04		/* file is a system file */
57 #define	ATTR_VOLUME	0x08		/* entry is a volume label */
58 #define	ATTR_DIRECTORY	0x10		/* entry is a directory name */
59 #define	ATTR_ARCHIVE	0x20		/* file is new or modified */
60 
61 #define	ATTR_WIN95	0x0f		/* long name record */
62 
63 /*
64  * This is the format of the contents of the deTime field in the direntry
65  * structure.
66  * We don't use bitfields because we don't know how compilers for
67  * arbitrary machines will lay them out.
68  */
69 #define DT_2SECONDS_MASK	0x1F	/* seconds divided by 2 */
70 #define DT_2SECONDS_SHIFT	0
71 #define DT_MINUTES_MASK		0x7E0	/* minutes */
72 #define DT_MINUTES_SHIFT	5
73 #define DT_HOURS_MASK		0xF800	/* hours */
74 #define DT_HOURS_SHIFT		11
75 
76 /*
77  * This is the format of the contents of the deDate field in the direntry
78  * structure.
79  */
80 #define DD_DAY_MASK		0x1F	/* day of month */
81 #define DD_DAY_SHIFT		0
82 #define DD_MONTH_MASK		0x1E0	/* month */
83 #define DD_MONTH_SHIFT		5
84 #define DD_YEAR_MASK		0xFE00	/* year - 1980 */
85 #define DD_YEAR_SHIFT		9
86 
87 
88 /* dir.c */
89 static struct dosDirEntry *newDosDirEntry(void);
90 static void freeDosDirEntry(struct dosDirEntry *);
91 static struct dirTodoNode *newDirTodo(void);
92 static void freeDirTodo(struct dirTodoNode *);
93 static char *fullpath(struct dosDirEntry *);
94 static u_char calcShortSum(u_char *);
95 static int delete(int, struct bootblock *, struct fatEntry *, cl_t, int,
96     cl_t, int, int);
97 static int removede(int, struct bootblock *, struct fatEntry *, u_char *,
98     u_char *, cl_t, cl_t, cl_t, char *, int);
99 static int checksize(struct bootblock *, struct fatEntry *, u_char *,
100     struct dosDirEntry *);
101 static int readDosDirSection(int, struct bootblock *, struct fatEntry *,
102     struct dosDirEntry *);
103 
104 /*
105  * Manage free dosDirEntry structures.
106  */
107 static struct dosDirEntry *freede;
108 
109 static struct dosDirEntry *
newDosDirEntry(void)110 newDosDirEntry(void)
111 {
112 	struct dosDirEntry *de;
113 
114 	if (!(de = freede)) {
115 		if (!(de = (struct dosDirEntry *)malloc(sizeof *de)))
116 			return 0;
117 	} else
118 		freede = de->next;
119 	return de;
120 }
121 
122 static void
freeDosDirEntry(struct dosDirEntry * de)123 freeDosDirEntry(struct dosDirEntry *de)
124 {
125 	de->next = freede;
126 	freede = de;
127 }
128 
129 /*
130  * The same for dirTodoNode structures.
131  */
132 static struct dirTodoNode *freedt;
133 
134 static struct dirTodoNode *
newDirTodo(void)135 newDirTodo(void)
136 {
137 	struct dirTodoNode *dt;
138 
139 	if (!(dt = freedt)) {
140 		if (!(dt = (struct dirTodoNode *)malloc(sizeof *dt)))
141 			return 0;
142 	} else
143 		freedt = dt->next;
144 	return dt;
145 }
146 
147 static void
freeDirTodo(struct dirTodoNode * dt)148 freeDirTodo(struct dirTodoNode *dt)
149 {
150 	dt->next = freedt;
151 	freedt = dt;
152 }
153 
154 /*
155  * The stack of unread directories
156  */
157 struct dirTodoNode *pendingDirectories = NULL;
158 
159 /*
160  * Return the full pathname for a directory entry.
161  */
162 static char *
fullpath(struct dosDirEntry * dir)163 fullpath(struct dosDirEntry *dir)
164 {
165 	static char namebuf[MAXPATHLEN + 1];
166 	char *cp, *np;
167 	int nl;
168 
169 	cp = namebuf + sizeof namebuf - 1;
170 	*cp = '\0';
171 	do {
172 		np = dir->lname[0] ? dir->lname : dir->name;
173 		nl = strlen(np);
174 		if ((cp -= nl) <= namebuf + 1)
175 			break;
176 		memcpy(cp, np, nl);
177 		*--cp = '/';
178 	} while ((dir = dir->parent) != NULL);
179 	if (dir)
180 		*--cp = '?';
181 	else
182 		cp++;
183 	return cp;
184 }
185 
186 /*
187  * Calculate a checksum over an 8.3 alias name
188  */
189 static u_char
calcShortSum(u_char * p)190 calcShortSum(u_char *p)
191 {
192 	u_char sum = 0;
193 	int i;
194 
195 	for (i = 0; i < 11; i++) {
196 		sum = (sum << 7)|(sum >> 1);	/* rotate right */
197 		sum += p[i];
198 	}
199 
200 	return sum;
201 }
202 
203 /*
204  * Global variables temporarily used during a directory scan
205  */
206 static char longName[DOSLONGNAMELEN] = "";
207 static char *eLongName = longName + sizeof(longName);
208 static u_char *buffer = NULL;
209 static u_char *delbuf = NULL;
210 
211 struct dosDirEntry *rootDir;
212 static struct dosDirEntry *lostDir;
213 
214 /*
215  * Init internal state for a new directory scan.
216  */
217 int
resetDosDirSection(struct bootblock * boot,struct fatEntry * fat)218 resetDosDirSection(struct bootblock *boot, struct fatEntry *fat)
219 {
220 	int b1, b2;
221 	cl_t cl;
222 	int ret = FSOK;
223 	size_t len;
224 
225 	b1 = boot->RootDirEnts * 32;
226 	b2 = boot->SecPerClust * boot->BytesPerSec;
227 
228 	if ((buffer = malloc(len = b1 > b2 ? b1 : b2)) == NULL) {
229 		perr("No space for directory buffer (%zu)", len);
230 		return FSFATAL;
231 	}
232 
233 	if ((delbuf = malloc(len = b2)) == NULL) {
234 		free(buffer);
235 		perr("No space for directory delbuf (%zu)", len);
236 		return FSFATAL;
237 	}
238 
239 	if ((rootDir = newDosDirEntry()) == NULL) {
240 		free(buffer);
241 		free(delbuf);
242 		perr("No space for directory entry");
243 		return FSFATAL;
244 	}
245 
246 	memset(rootDir, 0, sizeof *rootDir);
247 	if (boot->flags & FAT32) {
248 		if (boot->RootCl < CLUST_FIRST || boot->RootCl >= boot->NumClusters) {
249 			pfatal("Root directory starts with cluster out of range(%u)",
250 			       boot->RootCl);
251 			return FSFATAL;
252 		}
253 		cl = fat[boot->RootCl].next;
254 		if (cl < CLUST_FIRST
255 		    || (cl >= CLUST_RSRVD && cl< CLUST_EOFS)
256 		    || fat[boot->RootCl].head != boot->RootCl) {
257 			if (cl == CLUST_FREE)
258 				pwarn("Root directory starts with free cluster\n");
259 			else if (cl >= CLUST_RSRVD)
260 				pwarn("Root directory starts with cluster marked %s\n",
261 				      rsrvdcltype(cl));
262 			else {
263 				pfatal("Root directory doesn't start a cluster chain");
264 				return FSFATAL;
265 			}
266 			if (ask(1, "Fix")) {
267 				fat[boot->RootCl].next = CLUST_FREE;
268 				ret = FSFATMOD;
269 			} else
270 				ret = FSFATAL;
271 		}
272 
273 		fat[boot->RootCl].flags |= FAT_USED;
274 		rootDir->head = boot->RootCl;
275 	}
276 
277 	return ret;
278 }
279 
280 /*
281  * Cleanup after a directory scan
282  */
283 void
finishDosDirSection(void)284 finishDosDirSection(void)
285 {
286 	struct dirTodoNode *p, *np;
287 	struct dosDirEntry *d, *nd;
288 
289 	for (p = pendingDirectories; p; p = np) {
290 		np = p->next;
291 		freeDirTodo(p);
292 	}
293 	pendingDirectories = 0;
294 	for (d = rootDir; d; d = nd) {
295 		if ((nd = d->child) != NULL) {
296 			d->child = 0;
297 			continue;
298 		}
299 		if (!(nd = d->next))
300 			nd = d->parent;
301 		freeDosDirEntry(d);
302 	}
303 	rootDir = lostDir = NULL;
304 	free(buffer);
305 	free(delbuf);
306 	buffer = NULL;
307 	delbuf = NULL;
308 }
309 
310 /*
311  * Delete directory entries between startcl, startoff and endcl, endoff.
312  */
313 static int
delete(int f,struct bootblock * boot,struct fatEntry * fat,cl_t startcl,int startoff,cl_t endcl,int endoff,int notlast)314 delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
315        int startoff, cl_t endcl, int endoff, int notlast)
316 {
317 	u_char *s, *e;
318 	off_t off;
319 	int clsz = boot->SecPerClust * boot->BytesPerSec;
320 
321 	s = delbuf + startoff;
322 	e = delbuf + clsz;
323 	while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
324 		if (startcl == endcl) {
325 			if (notlast)
326 				break;
327 			e = delbuf + endoff;
328 		}
329 		off = (startcl - CLUST_FIRST) * boot->SecPerClust + boot->FirstCluster;
330 		off *= boot->BytesPerSec;
331 		if (lseek(f, off, SEEK_SET) != off
332 		    || read(f, delbuf, clsz) != clsz) {
333 			perr("Unable to read directory");
334 			return FSFATAL;
335 		}
336 		while (s < e) {
337 			*s = SLOT_DELETED;
338 			s += 32;
339 		}
340 		if (lseek(f, off, SEEK_SET) != off
341 		    || write(f, delbuf, clsz) != clsz) {
342 			perr("Unable to write directory");
343 			return FSFATAL;
344 		}
345 		if (startcl == endcl)
346 			break;
347 		startcl = fat[startcl].next;
348 		s = delbuf;
349 	}
350 	return FSOK;
351 }
352 
353 static int
removede(int f,struct bootblock * boot,struct fatEntry * fat,u_char * start,u_char * end,cl_t startcl,cl_t endcl,cl_t curcl,char * path,int type)354 removede(int f, struct bootblock *boot, struct fatEntry *fat, u_char *start,
355          u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path,
356 	 int type)
357 {
358 	switch (type) {
359 	case 0:
360 		pwarn("Invalid long filename entry for %s\n", path);
361 		break;
362 	case 1:
363 		pwarn("Invalid long filename entry at end of directory %s\n", path);
364 		break;
365 	case 2:
366 		pwarn("Invalid long filename entry for volume label\n");
367 		break;
368 	}
369 	if (ask(0, "Remove")) {
370 		if (startcl != curcl) {
371 			if (delete(f, boot, fat,
372 				   startcl, start - buffer,
373 				   endcl, end - buffer,
374 				   endcl == curcl) == FSFATAL)
375 				return FSFATAL;
376 			start = buffer;
377 		}
378 		/* startcl is < CLUST_FIRST for !fat32 root */
379 		if ((endcl == curcl) || (startcl < CLUST_FIRST))
380 			for (; start < end; start += 32)
381 				*start = SLOT_DELETED;
382 		return FSDIRMOD;
383 	}
384 	return FSERROR;
385 }
386 
387 /*
388  * Check an in-memory file entry
389  */
390 static int
checksize(struct bootblock * boot,struct fatEntry * fat,u_char * p,struct dosDirEntry * dir)391 checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
392 	  struct dosDirEntry *dir)
393 {
394 	/*
395 	 * Check size on ordinary files
396 	 */
397 	u_int32_t physicalSize;
398 
399 	if (dir->head == CLUST_FREE)
400 		physicalSize = 0;
401 	else {
402 		if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
403 			return FSERROR;
404 		physicalSize = fat[dir->head].length * boot->ClusterSize;
405 	}
406 	if (physicalSize < dir->size) {
407 		pwarn("size of %s is %u, should at most be %u\n",
408 		      fullpath(dir), dir->size, physicalSize);
409 		if (ask(1, "Truncate")) {
410 			dir->size = physicalSize;
411 			p[28] = (u_char)physicalSize;
412 			p[29] = (u_char)(physicalSize >> 8);
413 			p[30] = (u_char)(physicalSize >> 16);
414 			p[31] = (u_char)(physicalSize >> 24);
415 			return FSDIRMOD;
416 		} else
417 			return FSERROR;
418 	} else if (physicalSize - dir->size >= boot->ClusterSize) {
419 		pwarn("%s has too many clusters allocated\n",
420 		      fullpath(dir));
421 		if (ask(1, "Drop superfluous clusters")) {
422 			cl_t cl;
423 			u_int32_t sz, len;
424 
425 			for (cl = dir->head, len = sz = 0;
426 			    (sz += boot->ClusterSize) < dir->size; len++)
427 				cl = fat[cl].next;
428 			clearchain(boot, fat, fat[cl].next);
429 			fat[cl].next = CLUST_EOF;
430 			fat[dir->head].length = len;
431 			return FSFATMOD;
432 		} else
433 			return FSERROR;
434 	}
435 	return FSOK;
436 }
437 
438 static int
procName(int from,int to,char ** dst,const u_char * src)439 procName(int from, int to, char **dst, const u_char *src)
440 {
441 	int k;
442 	char *t = *dst;
443 
444 	for (k = from; k < to && t < eLongName; k += 2) {
445 		if (!src[k] && !src[k + 1])
446 			break;
447 		*t++ = src[k];
448 		/*
449 		 * Warn about those unusable chars in msdosfs here?	XXX
450 		 */
451 		if (src[k + 1])
452 		    t[-1] = '?';
453 	}
454 	*dst = t;
455 	return k;
456 }
457 
458 /*
459  * Read a directory and
460  *   - resolve long name records
461  *   - enter file and directory records into the parent's list
462  *   - push directories onto the todo-stack
463  */
464 static int
readDosDirSection(int f,struct bootblock * boot,struct fatEntry * fat,struct dosDirEntry * dir)465 readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
466 		  struct dosDirEntry *dir)
467 {
468 	struct dosDirEntry dirent, *d;
469 	u_char *p, *vallfn, *invlfn, *empty;
470 	off_t off;
471 	int i, j, k, last;
472 	cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
473 	char *t;
474 	u_int lidx = 0;
475 	int shortSum;
476 	int mod = FSOK;
477 #define	THISMOD	0x8000			/* Only used within this routine */
478 
479 	cl = dir->head;
480 	if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
481 		/*
482 		 * Already handled somewhere else.
483 		 */
484 		return FSOK;
485 	}
486 	shortSum = -1;
487 	vallfn = invlfn = empty = NULL;
488 	do {
489 		if (!(boot->flags & FAT32) && !dir->parent) {
490 			last = boot->RootDirEnts * 32;
491 			off = boot->ResSectors + boot->FATs * boot->FATsecs;
492 		} else {
493 			last = boot->SecPerClust * boot->BytesPerSec;
494 			off = (cl - CLUST_FIRST) * boot->SecPerClust + boot->FirstCluster;
495 		}
496 
497 		off *= boot->BytesPerSec;
498 		if (lseek(f, off, SEEK_SET) != off
499 		    || read(f, buffer, last) != last) {
500 			perr("Unable to read directory");
501 			return FSFATAL;
502 		}
503 		last /= 32;
504 		/*
505 		 * Check `.' and `..' entries here?			XXX
506 		 */
507 		for (p = buffer, i = 0; i < last; i++, p += 32) {
508 			if (dir->fsckflags & DIREMPWARN) {
509 				*p = SLOT_EMPTY;
510 				continue;
511 			}
512 
513 			if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
514 				if (*p == SLOT_EMPTY) {
515 					dir->fsckflags |= DIREMPTY;
516 					empty = p;
517 					empcl = cl;
518 				}
519 				continue;
520 			}
521 
522 			if (dir->fsckflags & DIREMPTY) {
523 				if (!(dir->fsckflags & DIREMPWARN)) {
524 					pwarn("%s has entries after end of directory\n",
525 					      fullpath(dir));
526 					if (ask(1, "Extend")) {
527 						u_char *q;
528 
529 						dir->fsckflags &= ~DIREMPTY;
530 						if (delete(f, boot, fat,
531 							   empcl, empty - buffer,
532 							   cl, p - buffer, 1) == FSFATAL)
533 							return FSFATAL;
534 						q = empcl == cl ? empty : buffer;
535 						assert(q != NULL);
536 						for (; q < p; q += 32)
537 							*q = SLOT_DELETED;
538 						mod |= THISMOD|FSDIRMOD;
539 					} else if (ask(0, "Truncate"))
540 						dir->fsckflags |= DIREMPWARN;
541 				}
542 				if (dir->fsckflags & DIREMPWARN) {
543 					*p = SLOT_DELETED;
544 					mod |= THISMOD|FSDIRMOD;
545 					continue;
546 				} else if (dir->fsckflags & DIREMPTY)
547 					mod |= FSERROR;
548 				empty = NULL;
549 			}
550 
551 			if (p[11] == ATTR_WIN95) {
552 				u_int lrnomask = *p & LRNOMASK;
553 				if (*p & LRFIRST) {
554 					if (shortSum != -1) {
555 						if (!invlfn) {
556 							invlfn = vallfn;
557 							invcl = valcl;
558 						}
559 					}
560 					memset(longName, 0, sizeof longName);
561 					shortSum = p[13];
562 					vallfn = p;
563 					valcl = cl;
564 				} else if (shortSum != p[13]
565 				   || lidx != lrnomask) {
566 					if (!invlfn) {
567 						invlfn = vallfn;
568 						invcl = valcl;
569 					}
570 					if (!invlfn) {
571 						invlfn = p;
572 						invcl = cl;
573 					}
574 					vallfn = NULL;
575 				}
576 				lidx = lrnomask;
577 				if (lidx != 0) {
578 					t = longName + --lidx * 13;
579 					k = procName(1, 11, &t, p);
580 					if (k >= 11)
581 						k = procName(14, 26, &t, p);
582 					if (k >= 26)
583 						k = procName(28, 32, &t, p);
584 					if (t >= eLongName) {
585 						pwarn(
586 						    "long filename too long\n");
587 						if (!invlfn) {
588 							invlfn = vallfn;
589 							invcl = valcl;
590 						}
591 						vallfn = NULL;
592 					}
593 				}
594 				if (p[26] | (p[27] << 8)) {
595 					pwarn("long filename record cluster "
596 					    "start != 0\n");
597 					if (!invlfn) {
598 						invlfn = vallfn;
599 						invcl = cl;
600 					}
601 					vallfn = NULL;
602 				}
603 				continue; 	/* long records don't carry
604 						 * further information */
605 			}
606 
607 			/*
608 			 * This is a standard msdosfs directory entry.
609 			 */
610 			memset(&dirent, 0, sizeof dirent);
611 
612 			/*
613 			 * it's a short name record, but we need to know
614 			 * more, so get the flags first.
615 			 */
616 			dirent.flags = p[11];
617 
618 			/*
619 			 * Translate from 850 to ISO here		XXX
620 			 */
621 			for (j = 0; j < 8; j++)
622 				dirent.name[j] = p[j];
623 			dirent.name[8] = '\0';
624 			for (k = 7; k >= 0 && dirent.name[k] == ' '; k--)
625 				dirent.name[k] = '\0';
626 			if (k < 0 || dirent.name[k] != '\0')
627 				k++;
628 			if (dirent.name[0] == SLOT_E5)
629 				dirent.name[0] = 0xe5;
630 
631 			if (dirent.flags & ATTR_VOLUME) {
632 				if (vallfn || invlfn) {
633 					mod |= removede(f, boot, fat,
634 							invlfn ? invlfn : vallfn, p,
635 							invlfn ? invcl : valcl, -1, 0,
636 							fullpath(dir), 2);
637 					vallfn = NULL;
638 					invlfn = NULL;
639 				}
640 				continue;
641 			}
642 
643 			if (p[8] != ' ')
644 				dirent.name[k++] = '.';
645 			for (j = 0; j < 3; j++)
646 				dirent.name[k++] = p[j+8];
647 			dirent.name[k] = '\0';
648 			for (k--; k >= 0 && dirent.name[k] == ' '; k--)
649 				dirent.name[k] = '\0';
650 
651 			if (vallfn && shortSum != calcShortSum(p)) {
652 				if (!invlfn) {
653 					invlfn = vallfn;
654 					invcl = valcl;
655 				}
656 				vallfn = NULL;
657 			}
658 			dirent.head = p[26] | (p[27] << 8);
659 			if (boot->ClustMask == CLUST32_MASK)
660 				dirent.head |= (p[20] << 16) | (p[21] << 24);
661 			dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24);
662 			if (vallfn) {
663 				strlcpy(dirent.lname, longName,
664 				    sizeof(dirent.lname));
665 				longName[0] = '\0';
666 				shortSum = -1;
667 			}
668 
669 			dirent.parent = dir;
670 			dirent.next = dir->child;
671 
672 			if (invlfn) {
673 				mod |= k = removede(f, boot, fat,
674 						    invlfn, vallfn ? vallfn : p,
675 						    invcl, vallfn ? valcl : cl, cl,
676 						    fullpath(&dirent), 0);
677 				if (mod & FSFATAL)
678 					return FSFATAL;
679 				if (vallfn
680 				    ? (valcl == cl && vallfn != buffer)
681 				    : p != buffer)
682 					if (k & FSDIRMOD)
683 						mod |= THISMOD;
684 			}
685 
686 			vallfn = NULL; /* not used any longer */
687 			invlfn = NULL;
688 
689 			if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
690 				if (dirent.head != 0) {
691 					pwarn("%s has clusters, but size 0\n",
692 					      fullpath(&dirent));
693 					if (ask(1, "Drop allocated clusters")) {
694 						p[26] = p[27] = 0;
695 						if (boot->ClustMask == CLUST32_MASK)
696 							p[20] = p[21] = 0;
697 						clearchain(boot, fat, dirent.head);
698 						dirent.head = 0;
699 						mod |= THISMOD|FSDIRMOD|FSFATMOD;
700 					} else
701 						mod |= FSERROR;
702 				}
703 			} else if (dirent.head == 0
704 				   && !strcmp(dirent.name, "..")
705 				   && dir->parent			/* XXX */
706 				   && !dir->parent->parent) {
707 				/*
708 				 *  Do nothing, the parent is the root
709 				 */
710 			} else if (dirent.head < CLUST_FIRST
711 				   || dirent.head >= boot->NumClusters
712 				   || fat[dirent.head].next == CLUST_FREE
713 				   || (fat[dirent.head].next >= CLUST_RSRVD
714 				       && fat[dirent.head].next < CLUST_EOFS)
715 				   || fat[dirent.head].head != dirent.head) {
716 				if (dirent.head == 0)
717 					pwarn("%s has no clusters\n",
718 					      fullpath(&dirent));
719 				else if (dirent.head < CLUST_FIRST
720 					 || dirent.head >= boot->NumClusters)
721 					pwarn("%s starts with cluster out of range(%u)\n",
722 					      fullpath(&dirent),
723 					      dirent.head);
724 				else if (fat[dirent.head].next == CLUST_FREE)
725 					pwarn("%s starts with free cluster\n",
726 					      fullpath(&dirent));
727 				else if (fat[dirent.head].next >= CLUST_RSRVD)
728 					pwarn("%s starts with cluster marked %s\n",
729 					      fullpath(&dirent),
730 					      rsrvdcltype(fat[dirent.head].next));
731 				else
732 					pwarn("%s doesn't start a cluster chain\n",
733 					      fullpath(&dirent));
734 				if (dirent.flags & ATTR_DIRECTORY) {
735 					if (ask(0, "Remove")) {
736 						*p = SLOT_DELETED;
737 						mod |= THISMOD|FSDIRMOD;
738 					} else
739 						mod |= FSERROR;
740 					continue;
741 				} else {
742 					if (ask(1, "Truncate")) {
743 						p[28] = p[29] = p[30] = p[31] = 0;
744 						p[26] = p[27] = 0;
745 						if (boot->ClustMask == CLUST32_MASK)
746 							p[20] = p[21] = 0;
747 						dirent.size = 0;
748 						mod |= THISMOD|FSDIRMOD;
749 					} else
750 						mod |= FSERROR;
751 				}
752 			}
753 
754 			if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
755 				fat[dirent.head].flags |= FAT_USED;
756 
757 			if (dirent.flags & ATTR_DIRECTORY) {
758 				/*
759 				 * gather more info for directories
760 				 */
761 				struct dirTodoNode *n;
762 
763 				if (dirent.size) {
764 					pwarn("Directory %s has size != 0\n",
765 					      fullpath(&dirent));
766 					if (ask(1, "Correct")) {
767 						p[28] = p[29] = p[30] = p[31] = 0;
768 						dirent.size = 0;
769 						mod |= THISMOD|FSDIRMOD;
770 					} else
771 						mod |= FSERROR;
772 				}
773 				/*
774 				 * handle `.' and `..' specially
775 				 */
776 				if (strcmp(dirent.name, ".") == 0) {
777 					if (dirent.head != dir->head) {
778 						pwarn("`.' entry in %s has incorrect start cluster\n",
779 						      fullpath(dir));
780 						if (ask(1, "Correct")) {
781 							dirent.head = dir->head;
782 							p[26] = (u_char)dirent.head;
783 							p[27] = (u_char)(dirent.head >> 8);
784 							if (boot->ClustMask == CLUST32_MASK) {
785 								p[20] = (u_char)(dirent.head >> 16);
786 								p[21] = (u_char)(dirent.head >> 24);
787 							}
788 							mod |= THISMOD|FSDIRMOD;
789 						} else
790 							mod |= FSERROR;
791 					}
792 					continue;
793 				}
794 				if (strcmp(dirent.name, "..") == 0) {
795 					if (dir->parent) {		/* XXX */
796 						if (!dir->parent->parent) {
797 							if (dirent.head) {
798 								pwarn("`..' entry in %s has non-zero start cluster\n",
799 								      fullpath(dir));
800 								if (ask(1, "Correct")) {
801 									dirent.head = 0;
802 									p[26] = p[27] = 0;
803 									if (boot->ClustMask == CLUST32_MASK)
804 										p[20] = p[21] = 0;
805 									mod |= THISMOD|FSDIRMOD;
806 								} else
807 									mod |= FSERROR;
808 							}
809 						} else if (dirent.head != dir->parent->head) {
810 							pwarn("`..' entry in %s has incorrect start cluster\n",
811 							      fullpath(dir));
812 							if (ask(1, "Correct")) {
813 								dirent.head = dir->parent->head;
814 								p[26] = (u_char)dirent.head;
815 								p[27] = (u_char)(dirent.head >> 8);
816 								if (boot->ClustMask == CLUST32_MASK) {
817 									p[20] = (u_char)(dirent.head >> 16);
818 									p[21] = (u_char)(dirent.head >> 24);
819 								}
820 								mod |= THISMOD|FSDIRMOD;
821 							} else
822 								mod |= FSERROR;
823 						}
824 					}
825 					continue;
826 				}
827 
828 				/* create directory tree node */
829 				if (!(d = newDosDirEntry())) {
830 					perr("No space for directory");
831 					return FSFATAL;
832 				}
833 				memcpy(d, &dirent, sizeof(struct dosDirEntry));
834 				/* link it into the tree */
835 				dir->child = d;
836 
837 				/* Enter this directory into the todo list */
838 				if (!(n = newDirTodo())) {
839 					perr("No space for todo list");
840 					return FSFATAL;
841 				}
842 				n->next = pendingDirectories;
843 				n->dir = d;
844 				pendingDirectories = n;
845 			} else {
846 				mod |= k = checksize(boot, fat, p, &dirent);
847 				if (k & FSDIRMOD)
848 					mod |= THISMOD;
849 			}
850 			boot->NumFiles++;
851 		}
852 
853 		if (!(boot->flags & FAT32) && !dir->parent)
854 			break;
855 
856 		if (mod & THISMOD) {
857 			last *= 32;
858 			if (lseek(f, off, SEEK_SET) != off
859 			    || write(f, buffer, last) != last) {
860 				perr("Unable to write directory");
861 				return FSFATAL;
862 			}
863 			mod &= ~THISMOD;
864 		}
865 	} while ((cl = fat[cl].next) >= CLUST_FIRST && cl < boot->NumClusters);
866 	if (invlfn || vallfn)
867 		mod |= removede(f, boot, fat,
868 				invlfn ? invlfn : vallfn, p,
869 				invlfn ? invcl : valcl, -1, 0,
870 				fullpath(dir), 1);
871 
872 	/* The root directory of non fat32 filesystems is in a special
873 	 * area and may have been modified above without being written out.
874 	 */
875 	if ((mod & FSDIRMOD) && !(boot->flags & FAT32) && !dir->parent) {
876 		last *= 32;
877 		if (lseek(f, off, SEEK_SET) != off
878 		    || write(f, buffer, last) != last) {
879 			perr("Unable to write directory");
880 			return FSFATAL;
881 		}
882 		mod &= ~THISMOD;
883 	}
884 	return mod & ~THISMOD;
885 }
886 
887 int
handleDirTree(int dosfs,struct bootblock * boot,struct fatEntry * fat)888 handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
889 {
890 	int mod;
891 
892 	mod = readDosDirSection(dosfs, boot, fat, rootDir);
893 	if (mod & FSFATAL)
894 		return FSFATAL;
895 
896 	/*
897 	 * process the directory todo list
898 	 */
899 	while (pendingDirectories) {
900 		struct dosDirEntry *dir = pendingDirectories->dir;
901 		struct dirTodoNode *n = pendingDirectories->next;
902 
903 		/*
904 		 * remove TODO entry now, the list might change during
905 		 * directory reads
906 		 */
907 		freeDirTodo(pendingDirectories);
908 		pendingDirectories = n;
909 
910 		/*
911 		 * handle subdirectory
912 		 */
913 		mod |= readDosDirSection(dosfs, boot, fat, dir);
914 		if (mod & FSFATAL)
915 			return FSFATAL;
916 	}
917 
918 	return mod;
919 }
920 
921 /*
922  * Try to reconnect a FAT chain into dir
923  */
924 static u_char *lfbuf;
925 static cl_t lfcl;
926 static off_t lfoff;
927 
928 int
reconnect(int dosfs,struct bootblock * boot,struct fatEntry * fat,cl_t head)929 reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
930 {
931 	struct dosDirEntry d;
932 	int len;
933 	u_char *p;
934 
935 	if (!ask(1, "Reconnect"))
936 		return FSERROR;
937 
938 	if (!lostDir) {
939 		for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
940 			if (!strcmp(lostDir->name, LOSTDIR))
941 				break;
942 		}
943 		if (!lostDir) {		/* Create LOSTDIR?		XXX */
944 			pwarn("No %s directory\n", LOSTDIR);
945 			return FSERROR;
946 		}
947 	}
948 	if (!lfbuf) {
949 		lfbuf = malloc(boot->ClusterSize);
950 		if (!lfbuf) {
951 			perr("No space for buffer");
952 			return FSFATAL;
953 		}
954 		p = NULL;
955 	} else
956 		p = lfbuf;
957 	while (1) {
958 		if (p)
959 			for (; p < lfbuf + boot->ClusterSize; p += 32)
960 				if (*p == SLOT_EMPTY
961 				    || *p == SLOT_DELETED)
962 					break;
963 		if (p && p < lfbuf + boot->ClusterSize)
964 			break;
965 		lfcl = p ? fat[lfcl].next : lostDir->head;
966 		if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) {
967 			/* Extend LOSTDIR?				XXX */
968 			pwarn("No space in %s\n", LOSTDIR);
969 			return FSERROR;
970 		}
971 		lfoff = (lfcl - CLUST_FIRST) * boot->ClusterSize
972 		    + boot->FirstCluster * boot->BytesPerSec;
973 		if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
974 		    || (size_t)read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
975 			perr("could not read LOST.DIR");
976 			return FSFATAL;
977 		}
978 		p = lfbuf;
979 	}
980 
981 	boot->NumFiles++;
982 	/* Ensure uniqueness of entry here!				XXX */
983 	memset(&d, 0, sizeof d);
984 	/* worst case -1 = 4294967295, 10 digits */
985 	len = snprintf(d.name, sizeof(d.name), "%u", head);
986 	d.flags = 0;
987 	d.head = head;
988 	d.size = fat[head].length * boot->ClusterSize;
989 
990 	memcpy(p, d.name, len);
991 	memset(p + len, ' ', 11 - len);
992 	memset(p + 11, 0, 32 - 11);
993 	p[26] = (u_char)d.head;
994 	p[27] = (u_char)(d.head >> 8);
995 	if (boot->ClustMask == CLUST32_MASK) {
996 		p[20] = (u_char)(d.head >> 16);
997 		p[21] = (u_char)(d.head >> 24);
998 	}
999 	p[28] = (u_char)d.size;
1000 	p[29] = (u_char)(d.size >> 8);
1001 	p[30] = (u_char)(d.size >> 16);
1002 	p[31] = (u_char)(d.size >> 24);
1003 	fat[head].flags |= FAT_USED;
1004 	if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
1005 	    || (size_t)write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
1006 		perr("could not write LOST.DIR");
1007 		return FSFATAL;
1008 	}
1009 	return FSDIRMOD;
1010 }
1011 
1012 void
finishlf(void)1013 finishlf(void)
1014 {
1015 	if (lfbuf)
1016 		free(lfbuf);
1017 	lfbuf = NULL;
1018 }
1019