xref: /openbsd/sbin/fsck_msdos/dir.c (revision 6a697e54)
1 /*	$OpenBSD: dir.c,v 1.31 2017/06/27 12:10:21 jsg Exp $	*/
2 /*	$NetBSD: dir.c,v 1.11 1997/10/17 11:19:35 ws Exp $	*/
3 
4 /*
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 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <ctype.h>
35 #include <unistd.h>
36 #include <limits.h>
37 #include <time.h>
38 
39 #include "ext.h"
40 
41 #define	SLOT_EMPTY	0x00		/* slot has never been used */
42 #define	SLOT_E5		0x05		/* the real value is 0xe5 */
43 #define	SLOT_DELETED	0xe5		/* file in this slot deleted */
44 
45 #define	ATTR_NORMAL	0x00		/* normal file */
46 #define	ATTR_READONLY	0x01		/* file is readonly */
47 #define	ATTR_HIDDEN	0x02		/* file is hidden */
48 #define	ATTR_SYSTEM	0x04		/* file is a system file */
49 #define	ATTR_VOLUME	0x08		/* entry is a volume label */
50 #define	ATTR_DIRECTORY	0x10		/* entry is a directory name */
51 #define	ATTR_ARCHIVE	0x20		/* file is new or modified */
52 
53 #define	ATTR_WIN95	0x0f		/* long name record */
54 
55 /*
56  * This is the format of the contents of the deTime field in the direntry
57  * structure.
58  * We don't use bitfields because we don't know how compilers for
59  * arbitrary machines will lay them out.
60  */
61 #define DT_2SECONDS_MASK	0x1F	/* seconds divided by 2 */
62 #define DT_2SECONDS_SHIFT	0
63 #define DT_MINUTES_MASK		0x7E0	/* minutes */
64 #define DT_MINUTES_SHIFT	5
65 #define DT_HOURS_MASK		0xF800	/* hours */
66 #define DT_HOURS_SHIFT		11
67 
68 /*
69  * This is the format of the contents of the deDate field in the direntry
70  * structure.
71  */
72 #define DD_DAY_MASK		0x1F	/* day of month */
73 #define DD_DAY_SHIFT		0
74 #define DD_MONTH_MASK		0x1E0	/* month */
75 #define DD_MONTH_SHIFT		5
76 #define DD_YEAR_MASK		0xFE00	/* year - 1980 */
77 #define DD_YEAR_SHIFT		9
78 
79 /* dir.c */
80 static struct dosDirEntry *newDosDirEntry(void);
81 static void freeDosDirEntry(struct dosDirEntry *);
82 static struct dirTodoNode *newDirTodo(void);
83 static void freeDirTodo(struct dirTodoNode *);
84 static char *fullpath(struct dosDirEntry *);
85 static u_char calcShortSum(u_char *);
86 static int delete(int, struct bootblock *, struct fatEntry *, cl_t, int,
87     cl_t, int, int);
88 static int removede(int, struct bootblock *, struct fatEntry *, u_char *,
89     u_char *, cl_t, cl_t, cl_t, char *, int);
90 static int checksize(struct bootblock *, struct fatEntry *, u_char *,
91     struct dosDirEntry *);
92 static int readDosDirSection(int, struct bootblock *, struct fatEntry *,
93     struct dosDirEntry *);
94 
95 /*
96  * Manage free dosDirEntry structures.
97  */
98 static struct dosDirEntry *freede;
99 
100 static struct dosDirEntry *
newDosDirEntry(void)101 newDosDirEntry(void)
102 {
103 	struct dosDirEntry *de;
104 
105 	if (!(de = freede)) {
106 		if (!(de = malloc(sizeof *de)))
107 			return (0);
108 	} else
109 		freede = de->next;
110 	return (de);
111 }
112 
113 static void
freeDosDirEntry(struct dosDirEntry * de)114 freeDosDirEntry(struct dosDirEntry *de)
115 {
116 	de->next = freede;
117 	freede = de;
118 }
119 
120 /*
121  * The same for dirTodoNode structures.
122  */
123 static struct dirTodoNode *freedt;
124 
125 static struct dirTodoNode *
newDirTodo(void)126 newDirTodo(void)
127 {
128 	struct dirTodoNode *dt;
129 
130 	if (!(dt = freedt)) {
131 		if (!(dt = malloc(sizeof *dt)))
132 			return (0);
133 	} else
134 		freedt = dt->next;
135 	return (dt);
136 }
137 
138 static void
freeDirTodo(struct dirTodoNode * dt)139 freeDirTodo(struct dirTodoNode *dt)
140 {
141 	dt->next = freedt;
142 	freedt = dt;
143 }
144 
145 /*
146  * The stack of unread directories
147  */
148 static struct dirTodoNode *pendingDirectories = NULL;
149 
150 /*
151  * Return the full pathname for a directory entry.
152  */
153 static char *
fullpath(struct dosDirEntry * dir)154 fullpath(struct dosDirEntry *dir)
155 {
156 	static char namebuf[PATH_MAX + 1];
157 	char *cp, *np;
158 	int nl;
159 
160 	cp = namebuf + sizeof namebuf;
161 	*--cp = '\0';
162 	for(;;) {
163 		np = dir->lname[0] ? dir->lname : dir->name;
164 		nl = strlen(np);
165 			/* cf dosDirEntry, sizeof(lname) < MAXPATHLEN, so test is safe */
166 		if (cp <= namebuf + 1 + nl) {
167 			*--cp = '?';
168 			break;
169 		}
170 		cp -= nl;
171 		(void)memcpy(cp, np, nl);
172 		dir = dir->parent;
173 		if (!dir)
174 			break;
175 		*--cp = '/';
176 	}
177 	return (cp);
178 }
179 
180 /*
181  * Calculate a checksum over an 8.3 alias name
182  */
183 static u_char
calcShortSum(u_char * p)184 calcShortSum(u_char *p)
185 {
186 	u_char sum = 0;
187 	int i;
188 
189 	for (i = 0; i < 11; i++) {
190 		sum = (sum << 7)|(sum >> 1);	/* rotate right */
191 		sum += p[i];
192 	}
193 
194 	return (sum);
195 }
196 
197 /*
198  * Global variables temporarily used during a directory scan
199  */
200 static char longName[DOSLONGNAMELEN] = "";
201 static u_char *buffer = NULL;
202 static u_char *delbuf = NULL;
203 
204 static struct dosDirEntry *rootDir;
205 static struct dosDirEntry *lostDir;
206 
207 /*
208  * Init internal state for a new directory scan.
209  */
210 int
resetDosDirSection(struct bootblock * boot,struct fatEntry * fat)211 resetDosDirSection(struct bootblock *boot, struct fatEntry *fat)
212 {
213 	int b1, b2;
214 	int ret = FSOK;
215 
216 	b1 = boot->RootDirEnts * 32;
217 	b2 = boot->SecPerClust * boot->BytesPerSec;
218 
219 	if (!(buffer = malloc(b1 > b2 ? b1 : b2))
220 	    || !(delbuf = malloc(b2))
221 	    || !(rootDir = newDosDirEntry())) {
222 		xperror("No space for directory");
223 		goto fail;
224 	}
225 	(void)memset(rootDir, 0, sizeof *rootDir);
226 	if (boot->flags & FAT32) {
227 		if (boot->RootCl < CLUST_FIRST || boot->RootCl >= boot->NumClusters) {
228 			pfatal("Root directory starts with cluster out of range(%u)\n",
229 			       boot->RootCl);
230 			goto fail;
231 		}
232 		if (fat[boot->RootCl].head != boot->RootCl) {
233 			pfatal("Root directory doesn't start a cluster chain\n");
234 			goto fail;
235 		}
236 
237 		fat[boot->RootCl].flags |= FAT_USED;
238 		rootDir->head = boot->RootCl;
239 	}
240 
241 	return (ret);
242 fail:
243 	finishDosDirSection();
244 	return (FSFATAL);
245 }
246 
247 /*
248  * Cleanup after a directory scan
249  */
250 void
finishDosDirSection(void)251 finishDosDirSection(void)
252 {
253 	struct dirTodoNode *p, *np;
254 	struct dosDirEntry *d, *nd;
255 
256 	for (p = pendingDirectories; p; p = np) {
257 		np = p->next;
258 		freeDirTodo(p);
259 	}
260 	pendingDirectories = 0;
261 	for (d = rootDir; d; d = nd) {
262 		if ((nd = d->child) != NULL) {
263 			d->child = 0;
264 			continue;
265 		}
266 		if (!(nd = d->next))
267 			nd = d->parent;
268 		freeDosDirEntry(d);
269 	}
270 	rootDir = lostDir = NULL;
271 	free(buffer);
272 	free(delbuf);
273 	buffer = NULL;
274 	delbuf = NULL;
275 }
276 
277 /*
278  * Delete directory entries between startcl, startoff and endcl, endoff.
279  */
280 static int
delete(int f,struct bootblock * boot,struct fatEntry * fat,cl_t startcl,int startoff,cl_t endcl,int endoff,int notlast)281 delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
282        int startoff, cl_t endcl, int endoff, int notlast)
283 {
284 	u_char *s, *e;
285 	off_t off;
286 	int clsz = boot->SecPerClust * boot->BytesPerSec;
287 
288 	s = delbuf + startoff;
289 	e = delbuf + clsz;
290 	while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
291 		if (startcl == endcl) {
292 			if (notlast)
293 				break;
294 			e = delbuf + endoff;
295 		}
296 		off = startcl * boot->SecPerClust + boot->ClusterOffset;
297 		off *= boot->BytesPerSec;
298 		if (lseek(f, off, SEEK_SET) != off
299 		    || read(f, delbuf, clsz) != clsz) {
300 			xperror("Unable to read directory");
301 			return (FSFATAL);
302 		}
303 		while (s < e) {
304 			*s = SLOT_DELETED;
305 			s += 32;
306 		}
307 		if (lseek(f, off, SEEK_SET) != off
308 		    || write(f, delbuf, clsz) != clsz) {
309 			xperror("Unable to write directory");
310 			return (FSFATAL);
311 		}
312 		if (startcl == endcl)
313 			break;
314 		startcl = fat[startcl].next;
315 		s = delbuf;
316 	}
317 	return (FSOK);
318 }
319 
320 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)321 removede(int f, struct bootblock *boot, struct fatEntry *fat, u_char *start,
322 	 u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path, int type)
323 {
324 	switch (type) {
325 	case 0:
326 		pwarn("Invalid long filename entry for %s\n", path);
327 		break;
328 	case 1:
329 		pwarn("Invalid long filename entry at end of directory %s\n", path);
330 		break;
331 	case 2:
332 		pwarn("Invalid long filename entry for volume label\n");
333 		break;
334 	}
335 	if (ask(0, "Remove")) {
336 		if (startcl != curcl) {
337 			if (delete(f, boot, fat,
338 				   startcl, start - buffer,
339 				   endcl, end - buffer,
340 				   endcl == curcl) == FSFATAL)
341 				return (FSFATAL);
342 			start = buffer;
343 		}
344 		if (endcl == curcl)
345 			for (; start < end; start += 32)
346 				*start = SLOT_DELETED;
347 		return (FSDIRMOD);
348 	}
349 	return (FSERROR);
350 }
351 
352 /*
353  * Check an in-memory file entry
354  */
355 static int
checksize(struct bootblock * boot,struct fatEntry * fat,u_char * p,struct dosDirEntry * dir)356 checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
357 	  struct dosDirEntry *dir)
358 {
359 	/*
360 	 * Check size on ordinary files
361 	 */
362 	u_int32_t physicalSize;
363 
364 	if (dir->head == CLUST_FREE)
365 		physicalSize = 0;
366 	else {
367 		if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
368 			return (FSERROR);
369 		physicalSize = fat[dir->head].length * boot->ClusterSize;
370 	}
371 	if (physicalSize < dir->size) {
372 		pwarn("size of %s is %u, should at most be %u\n",
373 		      fullpath(dir), dir->size, physicalSize);
374 		if (ask(1, "Truncate")) {
375 			dir->size = physicalSize;
376 			p[28] = (u_char)physicalSize;
377 			p[29] = (u_char)(physicalSize >> 8);
378 			p[30] = (u_char)(physicalSize >> 16);
379 			p[31] = (u_char)(physicalSize >> 24);
380 			return (FSDIRMOD);
381 		} else
382 			return (FSERROR);
383 	} else if (physicalSize - dir->size >= boot->ClusterSize) {
384 		pwarn("%s has too many clusters allocated\n",
385 		      fullpath(dir));
386 		if (ask(1, "Drop superfluous clusters")) {
387 			cl_t cl;
388 			u_int32_t len, sz;
389 
390 			len = sz = 0;
391 			for (cl = dir->head; (sz += boot->ClusterSize) < dir->size;) {
392 				cl = fat[cl].next;
393 				len++;
394 			}
395 			clearchain(boot, fat, fat[cl].next);
396 			fat[cl].next = CLUST_EOF;
397 			fat[dir->head].length = len;
398 			return (FSFATMOD);
399 		} else
400 			return (FSERROR);
401 	}
402 	return (FSOK);
403 }
404 
405 /*
406  * Read a directory and
407  *   - resolve long name records
408  *   - enter file and directory records into the parent's list
409  *   - push directories onto the todo-stack
410  */
411 static int
readDosDirSection(int f,struct bootblock * boot,struct fatEntry * fat,struct dosDirEntry * dir)412 readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
413 		  struct dosDirEntry *dir)
414 {
415 	struct dosDirEntry dirent, *d;
416 	u_char *p, *vallfn, *invlfn, *empty;
417 	off_t off;
418 	int i, j, k, last;
419 	cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
420 	char *t;
421 	u_int lidx = 0;
422 	int shortSum;
423 	int mod = FSOK;
424 #define	THISMOD	0x8000			/* Only used within this routine */
425 
426 	cl = dir->head;
427 	if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
428 		/*
429 		 * Already handled somewhere else.
430 		 */
431 		return (FSOK);
432 	}
433 	shortSum = -1;
434 	vallfn = invlfn = empty = NULL;
435 	do {
436 		if (!(boot->flags & FAT32) && !dir->parent) {
437 			last = boot->RootDirEnts * 32;
438 			off = boot->ResSectors + boot->FATs * boot->FATsecs;
439 		} else {
440 			last = boot->SecPerClust * boot->BytesPerSec;
441 			off = cl * boot->SecPerClust + boot->ClusterOffset;
442 		}
443 
444 		off *= boot->BytesPerSec;
445 		if (lseek(f, off, SEEK_SET) != off
446 		    || read(f, buffer, last) != last) {
447 			xperror("Unable to read directory");
448 			return (FSFATAL);
449 		}
450 		last /= 32;
451 		/*
452 		 * Check `.' and `..' entries here?			XXX
453 		 */
454 		for (p = buffer, i = 0; i < last; i++, p += 32) {
455 			if (dir->fsckflags & DIREMPWARN) {
456 				*p = SLOT_EMPTY;
457 				continue;
458 			}
459 
460 			if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
461 				if (*p == SLOT_EMPTY) {
462 					dir->fsckflags |= DIREMPTY;
463 					empty = p;
464 					empcl = cl;
465 				}
466 				continue;
467 			}
468 
469 			if (dir->fsckflags & DIREMPTY) {
470 				if (!(dir->fsckflags & DIREMPWARN)) {
471 					pwarn("%s has entries after end of directory\n",
472 					      fullpath(dir));
473 					if (ask(1, "Extend")) {
474 						u_char *q;
475 
476 						dir->fsckflags &= ~DIREMPTY;
477 						if (delete(f, boot, fat,
478 							   empcl, empty - buffer,
479 							   cl, p - buffer, 1) == FSFATAL)
480 							return (FSFATAL);
481 						q = empcl == cl ? empty : buffer;
482 						for (; q < p; q += 32)
483 							*q = SLOT_DELETED;
484 						mod |= THISMOD|FSDIRMOD;
485 					} else if (ask(0, "Truncate"))
486 						dir->fsckflags |= DIREMPWARN;
487 				}
488 				if (dir->fsckflags & DIREMPWARN) {
489 					*p = SLOT_DELETED;
490 					mod |= THISMOD|FSDIRMOD;
491 					continue;
492 				} else if (dir->fsckflags & DIREMPTY)
493 					mod |= FSERROR;
494 				empty = NULL;
495 			}
496 
497 			if (p[11] == ATTR_WIN95) {
498 				if (*p & LRFIRST) {
499 					if (shortSum != -1) {
500 						if (!invlfn) {
501 							invlfn = vallfn;
502 							invcl = valcl;
503 						}
504 					}
505 					(void)memset(longName, 0, sizeof longName);
506 					shortSum = p[13];
507 					vallfn = p;
508 					valcl = cl;
509 				} else if (shortSum != p[13]
510 					   || lidx != (*p & LRNOMASK)) {
511 					if (!invlfn) {
512 						invlfn = vallfn;
513 						invcl = valcl;
514 					}
515 					if (!invlfn) {
516 						invlfn = p;
517 						invcl = cl;
518 					}
519 					vallfn = NULL;
520 				}
521 				lidx = *p & LRNOMASK;
522 				if (lidx == 0) {
523 					if (!invlfn) {
524 						invlfn = vallfn;
525 						invcl = valcl;
526 					}
527 					vallfn = NULL;
528 					continue;
529 				}
530 				t = longName + --lidx * 13;
531 				for (k = 1; k < 11 && t < longName + sizeof(longName); k += 2) {
532 					if (!p[k] && !p[k + 1])
533 						break;
534 					*t++ = p[k];
535 					/*
536 					 * Warn about those unusable chars in msdosfs here?	XXX
537 					 */
538 					if (p[k + 1])
539 						t[-1] = '?';
540 				}
541 				if (k >= 11)
542 					for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
543 						if (!p[k] && !p[k + 1])
544 							break;
545 						*t++ = p[k];
546 						if (p[k + 1])
547 							t[-1] = '?';
548 					}
549 				if (k >= 26)
550 					for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
551 						if (!p[k] && !p[k + 1])
552 							break;
553 						*t++ = p[k];
554 						if (p[k + 1])
555 							t[-1] = '?';
556 					}
557 				if (t >= longName + sizeof(longName)) {
558 					pwarn("long filename too long\n");
559 					if (!invlfn) {
560 						invlfn = vallfn;
561 						invcl = valcl;
562 					}
563 					vallfn = NULL;
564 				}
565 				if (p[26] | (p[27] << 8)) {
566 					pwarn("long filename record cluster start != 0\n");
567 					if (!invlfn) {
568 						invlfn = vallfn;
569 						invcl = cl;
570 					}
571 					vallfn = NULL;
572 				}
573 				continue;	/* long records don't carry further
574 						 * information */
575 			}
576 
577 			/*
578 			 * This is a standard msdosfs directory entry.
579 			 */
580 			(void)memset(&dirent, 0, sizeof dirent);
581 
582 			/*
583 			 * it's a short name record, but we need to know
584 			 * more, so get the flags first.
585 			 */
586 			dirent.flags = p[11];
587 
588 			/*
589 			 * Translate from 850 to ISO here		XXX
590 			 */
591 			for (j = 0; j < 8; j++)
592 				dirent.name[j] = p[j];
593 			dirent.name[8] = '\0';
594 			for (k = 7; k >= 0 && dirent.name[k] == ' '; k--)
595 				dirent.name[k] = '\0';
596 			if (k < 0)
597 				k = 0;
598 			if (dirent.name[k] != '\0')
599 				k++;
600 			if (dirent.name[0] == SLOT_E5)
601 				dirent.name[0] = 0xe5;
602 
603 			if (dirent.flags & ATTR_VOLUME) {
604 				if (vallfn || invlfn) {
605 					mod |= removede(f, boot, fat,
606 							invlfn ? invlfn : vallfn, p,
607 							invlfn ? invcl : valcl, -1, 0,
608 							fullpath(dir), 2);
609 					vallfn = NULL;
610 					invlfn = NULL;
611 				}
612 				continue;
613 			}
614 
615 			if (p[8] != ' ')
616 				dirent.name[k++] = '.';
617 			for (j = 0; j < 3; j++)
618 				dirent.name[k++] = p[j+8];
619 			dirent.name[k] = '\0';
620 			for (k--; k >= 0 && dirent.name[k] == ' '; k--)
621 				dirent.name[k] = '\0';
622 
623 			if (vallfn && shortSum != calcShortSum(p)) {
624 				if (!invlfn) {
625 					invlfn = vallfn;
626 					invcl = valcl;
627 				}
628 				vallfn = NULL;
629 			}
630 			dirent.head = p[26] | (p[27] << 8);
631 			if (boot->ClustMask == CLUST32_MASK)
632 				dirent.head |= (p[20] << 16) | (p[21] << 24);
633 			dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24);
634 			if (vallfn) {
635 				strlcpy(dirent.lname, longName, sizeof dirent.lname);
636 				longName[0] = '\0';
637 				shortSum = -1;
638 			}
639 
640 			dirent.parent = dir;
641 			dirent.next = dir->child;
642 
643 			if (invlfn) {
644 				mod |= k = removede(f, boot, fat,
645 						    invlfn, vallfn ? vallfn : p,
646 						    invcl, vallfn ? valcl : cl, cl,
647 						    fullpath(&dirent), 0);
648 				if (mod & FSFATAL)
649 					return (FSFATAL);
650 				if (vallfn
651 				    ? (valcl == cl && vallfn != buffer)
652 				    : p != buffer)
653 					if (k & FSDIRMOD)
654 						mod |= THISMOD;
655 			}
656 
657 			vallfn = NULL; /* not used any longer */
658 			invlfn = NULL;
659 
660 			if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
661 				if (dirent.head != 0) {
662 					pwarn("%s has clusters, but size 0\n",
663 					      fullpath(&dirent));
664 					if (ask(1, "Drop allocated clusters")) {
665 						p[26] = p[27] = 0;
666 						if (boot->ClustMask == CLUST32_MASK)
667 							p[20] = p[21] = 0;
668 						clearchain(boot, fat, dirent.head);
669 						dirent.head = 0;
670 						mod |= THISMOD|FSDIRMOD|FSFATMOD;
671 					} else
672 						mod |= FSERROR;
673 				}
674 			} else if (dirent.head == 0
675 				   && !strcmp(dirent.name, "..")
676 				   && dir->parent			/* XXX */
677 				   && !dir->parent->parent) {
678 				/*
679 				 *  Do nothing, the parent is the root
680 				 */
681 			} else if (dirent.head < CLUST_FIRST
682 				   || dirent.head >= boot->NumClusters
683 				   || fat[dirent.head].next == CLUST_FREE
684 				   || (fat[dirent.head].next >= CLUST_RSRVD
685 				       && fat[dirent.head].next < CLUST_EOFS)
686 				   || fat[dirent.head].head != dirent.head) {
687 				if (dirent.head == 0)
688 					pwarn("%s has no clusters\n",
689 					      fullpath(&dirent));
690 				else if (dirent.head < CLUST_FIRST
691 					 || dirent.head >= boot->NumClusters)
692 					pwarn("%s starts with cluster out of range(%u)\n",
693 					      fullpath(&dirent),
694 					      dirent.head);
695 				else if (fat[dirent.head].next == CLUST_FREE)
696 					pwarn("%s starts with free cluster\n",
697 					      fullpath(&dirent));
698 				else if (fat[dirent.head].next >= CLUST_RSRVD)
699 					pwarn("%s starts with cluster marked %s\n",
700 					      fullpath(&dirent),
701 					      rsrvdcltype(fat[dirent.head].next));
702 				else
703 					pwarn("%s doesn't start a cluster chain\n",
704 					      fullpath(&dirent));
705 				if (dirent.flags & ATTR_DIRECTORY) {
706 					if (ask(0, "Remove")) {
707 						*p = SLOT_DELETED;
708 						mod |= THISMOD|FSDIRMOD;
709 					} else
710 						mod |= FSERROR;
711 					continue;
712 				} else {
713 					if (ask(1, "Truncate")) {
714 						p[28] = p[29] = p[30] = p[31] = 0;
715 						p[26] = p[27] = 0;
716 						if (boot->ClustMask == CLUST32_MASK)
717 							p[20] = p[21] = 0;
718 						dirent.size = 0;
719 						mod |= THISMOD|FSDIRMOD;
720 					} else
721 						mod |= FSERROR;
722 				}
723 			}
724 
725 			if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
726 				fat[dirent.head].flags |= FAT_USED;
727 
728 			if (dirent.flags & ATTR_DIRECTORY) {
729 				/*
730 				 * gather more info for directories
731 				 */
732 				struct dirTodoNode *n;
733 
734 				if (dirent.size) {
735 					pwarn("Directory %s has size != 0\n",
736 					      fullpath(&dirent));
737 					if (ask(1, "Correct")) {
738 						p[28] = p[29] = p[30] = p[31] = 0;
739 						dirent.size = 0;
740 						mod |= THISMOD|FSDIRMOD;
741 					} else
742 						mod |= FSERROR;
743 				}
744 				/*
745 				 * handle `.' and `..' specially
746 				 */
747 				if (strcmp(dirent.name, ".") == 0) {
748 					if (dirent.head != dir->head) {
749 						pwarn("`.' entry in %s has incorrect start cluster\n",
750 						      fullpath(dir));
751 						if (ask(1, "Correct")) {
752 							dirent.head = dir->head;
753 							p[26] = (u_char)dirent.head;
754 							p[27] = (u_char)(dirent.head >> 8);
755 							if (boot->ClustMask == CLUST32_MASK) {
756 								p[20] = (u_char)(dirent.head >> 16);
757 								p[21] = (u_char)(dirent.head >> 24);
758 							}
759 							mod |= THISMOD|FSDIRMOD;
760 						} else
761 							mod |= FSERROR;
762 					}
763 					continue;
764 				}
765 				if (strcmp(dirent.name, "..") == 0) {
766 					if (dir->parent) {		/* XXX */
767 						if (!dir->parent->parent) {
768 							if (dirent.head) {
769 								pwarn("`..' entry in %s has non-zero start cluster\n",
770 								      fullpath(dir));
771 								if (ask(1, "Correct")) {
772 									dirent.head = 0;
773 									p[26] = p[27] = 0;
774 									if (boot->ClustMask == CLUST32_MASK)
775 										p[20] = p[21] = 0;
776 									mod |= THISMOD|FSDIRMOD;
777 								} else
778 									mod |= FSERROR;
779 							}
780 						} else if (dirent.head != dir->parent->head) {
781 							pwarn("`..' entry in %s has incorrect start cluster\n",
782 							      fullpath(dir));
783 							if (ask(1, "Correct")) {
784 								dirent.head = dir->parent->head;
785 								p[26] = (u_char)dirent.head;
786 								p[27] = (u_char)(dirent.head >> 8);
787 								if (boot->ClustMask == CLUST32_MASK) {
788 									p[20] = (u_char)(dirent.head >> 16);
789 									p[21] = (u_char)(dirent.head >> 24);
790 								}
791 								mod |= THISMOD|FSDIRMOD;
792 							} else
793 								mod |= FSERROR;
794 						}
795 					}
796 					continue;
797 				}
798 
799 				/* create directory tree node */
800 				if (!(d = newDosDirEntry())) {
801 					xperror("No space for directory");
802 					return (FSFATAL);
803 				}
804 				(void)memcpy(d, &dirent, sizeof(struct dosDirEntry));
805 				/* link it into the tree */
806 				dir->child = d;
807 
808 				/* Enter this directory into the todo list */
809 				if (!(n = newDirTodo())) {
810 					xperror("No space for todo list");
811 					return (FSFATAL);
812 				}
813 				n->next = pendingDirectories;
814 				n->dir = d;
815 				pendingDirectories = n;
816 			} else {
817 				mod |= k = checksize(boot, fat, p, &dirent);
818 				if (k & FSDIRMOD)
819 					mod |= THISMOD;
820 			}
821 			boot->NumFiles++;
822 		}
823 		if (mod & THISMOD) {
824 			last *= 32;
825 			if (lseek(f, off, SEEK_SET) != off
826 			    || write(f, buffer, last) != last) {
827 				xperror("Unable to write directory");
828 				return (FSFATAL);
829 			}
830 			mod &= ~THISMOD;
831 		}
832 	} while ((cl = fat[cl].next) >= CLUST_FIRST && cl < boot->NumClusters);
833 	if (invlfn || vallfn)
834 		mod |= removede(f, boot, fat,
835 				invlfn ? invlfn : vallfn, p,
836 				invlfn ? invcl : valcl, -1, 0,
837 				fullpath(dir), 1);
838 	return (mod & ~THISMOD);
839 }
840 
841 int
handleDirTree(int dosfs,struct bootblock * boot,struct fatEntry * fat)842 handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
843 {
844 	int mod;
845 
846 	mod = readDosDirSection(dosfs, boot, fat, rootDir);
847 	if (mod & FSFATAL)
848 		return (FSFATAL);
849 
850 	if (mod & FSFATMOD) {
851 		mod &= ~FSFATMOD;
852 		mod |= writefat(dosfs, boot, fat); /* delay writing fats?	XXX */
853 	}
854 
855 	if (mod & FSFATAL)
856 		return (FSFATAL);
857 
858 	/*
859 	 * process the directory todo list
860 	 */
861 	while (pendingDirectories) {
862 		struct dosDirEntry *dir = pendingDirectories->dir;
863 		struct dirTodoNode *n = pendingDirectories->next;
864 
865 		/*
866 		 * remove TODO entry now, the list might change during
867 		 * directory reads
868 		 */
869 		freeDirTodo(pendingDirectories);
870 		pendingDirectories = n;
871 
872 		/*
873 		 * handle subdirectory
874 		 */
875 		mod |= readDosDirSection(dosfs, boot, fat, dir);
876 		if (mod & FSFATAL)
877 			return (FSFATAL);
878 		if (mod & FSFATMOD) {
879 			mod &= ~FSFATMOD;
880 			mod |= writefat(dosfs, boot, fat); /* delay writing fats? XXX */
881 		}
882 		if (mod & FSFATAL)
883 			return (FSFATAL);
884 	}
885 	return (mod);
886 }
887 
888 /*
889  * Try to reconnect a FAT chain into dir
890  */
891 static u_char *lfbuf;
892 static cl_t lfcl;
893 static off_t lfoff;
894 
895 int
reconnect(int dosfs,struct bootblock * boot,struct fatEntry * fat,cl_t head)896 reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
897 {
898 	struct dosDirEntry d;
899 	u_char *p;
900 
901 	if (!ask(1, "Reconnect"))
902 		return FSERROR;
903 
904 	if (!lostDir) {
905 		for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
906 			if (!strcmp(lostDir->name, LOSTDIR))
907 				break;
908 		}
909 		if (!lostDir) {		/* Create LOSTDIR?		XXX */
910 			pwarn("No %s directory\n", LOSTDIR);
911 			return (FSERROR);
912 		}
913 	}
914 	if (!lfbuf) {
915 		lfbuf = malloc(boot->ClusterSize);
916 		if (!lfbuf) {
917 			xperror("No space for buffer");
918 			return (FSFATAL);
919 		}
920 		p = NULL;
921 	} else
922 		p = lfbuf;
923 	while (1) {
924 		if (p)
925 			for (; p < lfbuf + boot->ClusterSize; p += 32)
926 				if (*p == SLOT_EMPTY
927 				    || *p == SLOT_DELETED)
928 					break;
929 		if (p && p < lfbuf + boot->ClusterSize)
930 			break;
931 		lfcl = p ? fat[lfcl].next : lostDir->head;
932 		if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) {
933 			/* Extend LOSTDIR?				XXX */
934 			pwarn("No space in %s\n", LOSTDIR);
935 			return (FSERROR);
936 		}
937 		lfoff = lfcl * boot->ClusterSize
938 		    + boot->ClusterOffset * boot->BytesPerSec;
939 		if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
940 		    || read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
941 			xperror("could not read LOST.DIR");
942 			return (FSFATAL);
943 		}
944 		p = lfbuf;
945 	}
946 
947 	boot->NumFiles++;
948 	/* Ensure uniqueness of entry here!				XXX */
949 	(void)memset(&d, 0, sizeof d);
950 	snprintf(d.name, sizeof d.name, "%u", head);
951 	d.flags = 0;
952 	d.head = head;
953 	d.size = fat[head].length * boot->ClusterSize;
954 
955 	(void)memset(p, 0, 32);
956 	(void)memset(p, ' ', 11);
957 	(void)memcpy(p, d.name, strlen(d.name));
958 	p[26] = (u_char)d.head;
959 	p[27] = (u_char)(d.head >> 8);
960 	if (boot->ClustMask == CLUST32_MASK) {
961 		p[20] = (u_char)(d.head >> 16);
962 		p[21] = (u_char)(d.head >> 24);
963 	}
964 	p[28] = (u_char)d.size;
965 	p[29] = (u_char)(d.size >> 8);
966 	p[30] = (u_char)(d.size >> 16);
967 	p[31] = (u_char)(d.size >> 24);
968 	fat[head].flags |= FAT_USED;
969 	if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
970 	    || write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
971 		xperror("could not write LOST.DIR");
972 		return (FSFATAL);
973 	}
974 	return (FSDIRMOD);
975 }
976 
977 void
finishlf(void)978 finishlf(void)
979 {
980 	free(lfbuf);
981 	lfbuf = NULL;
982 }
983