xref: /netbsd/sbin/fsck_ffs/setup.c (revision c4a72b64)
1 /*	$NetBSD: setup.c,v 1.55 2002/11/05 05:18:50 dbj Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)setup.c	8.10 (Berkeley) 5/9/95";
40 #else
41 __RCSID("$NetBSD: setup.c,v 1.55 2002/11/05 05:18:50 dbj Exp $");
42 #endif
43 #endif /* not lint */
44 
45 #include <sys/param.h>
46 #include <sys/time.h>
47 #include <sys/stat.h>
48 #include <sys/ioctl.h>
49 #define FSTYPENAMES
50 #include <sys/disklabel.h>
51 #include <sys/file.h>
52 
53 #include <ufs/ufs/dinode.h>
54 #include <ufs/ufs/dir.h>
55 #include <ufs/ufs/ufs_bswap.h>
56 #include <ufs/ffs/fs.h>
57 #include <ufs/ffs/ffs_extern.h>
58 
59 #include <ctype.h>
60 #include <err.h>
61 #include <errno.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 
66 #include "fsck.h"
67 #include "extern.h"
68 #include "fsutil.h"
69 
70 #define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
71 
72 static void badsb __P((int, char *));
73 static int calcsb __P((const char *, int, struct fs *));
74 static struct disklabel *getdisklabel __P((const char *, int));
75 static struct partition *getdisklabelpart __P((const char *, struct disklabel *));
76 static int readsb __P((int));
77 static int readappleufs __P((void));
78 
79 /*
80  * Read in a superblock finding an alternate if necessary.
81  * Return 1 if successful, 0 if unsuccessful, -1 if filesystem
82  * is already clean (preen mode only).
83  */
84 int
85 setup(dev)
86 	const char *dev;
87 {
88 	long cg, size, asked, i, j;
89 	long bmapsize;
90 	struct disklabel *lp;
91 	off_t sizepb;
92 	struct stat statb;
93 	struct fs proto;
94 	int doskipclean;
95 	u_int64_t maxfilesize;
96 	struct csum *ccsp;
97 
98 	havesb = 0;
99 	fswritefd = -1;
100 	doskipclean = skipclean;
101 	if (stat(dev, &statb) < 0) {
102 		printf("Can't stat %s: %s\n", dev, strerror(errno));
103 		return (0);
104 	}
105 	if (!forceimage && !S_ISCHR(statb.st_mode)) {
106 		pfatal("%s is not a character device", dev);
107 		if (reply("CONTINUE") == 0)
108 			return (0);
109 	}
110 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
111 		printf("Can't open %s: %s\n", dev, strerror(errno));
112 		return (0);
113 	}
114 	if (preen == 0)
115 		printf("** %s", dev);
116 	if (nflag || (fswritefd = open(dev, O_WRONLY)) < 0) {
117 		fswritefd = -1;
118 		if (preen)
119 			pfatal("NO WRITE ACCESS");
120 		printf(" (NO WRITE)");
121 	}
122 	if (preen == 0)
123 		printf("\n");
124 	fsmodified = 0;
125 	lfdir = 0;
126 	initbarea(&sblk);
127 	initbarea(&asblk);
128 	sblk.b_un.b_buf = malloc(SBSIZE);
129 	sblock = malloc(SBSIZE);
130 	asblk.b_un.b_buf = malloc(SBSIZE);
131 	altsblock = malloc(SBSIZE);
132 	if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL ||
133 		sblock == NULL || altsblock == NULL)
134 		errx(EEXIT, "cannot allocate space for superblock");
135 	if (!forceimage && (lp = getdisklabel(NULL, fsreadfd)) != NULL)
136 		dev_bsize = secsize = lp->d_secsize;
137 	else
138 		dev_bsize = secsize = DEV_BSIZE;
139 	/*
140 	 * Read in the superblock, looking for alternates if necessary
141 	 */
142 	if (readsb(1) == 0) {
143 		if (bflag || preen || forceimage ||
144 		    calcsb(dev, fsreadfd, &proto) == 0)
145 			return(0);
146 		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
147 			return (0);
148 		for (cg = 0; cg < proto.fs_ncg; cg++) {
149 			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
150 			if (readsb(0) != 0)
151 				break;
152 		}
153 		if (cg >= proto.fs_ncg) {
154 			printf("%s %s\n%s %s\n%s %s\n",
155 				"SEARCH FOR ALTERNATE SUPER-BLOCK",
156 				"FAILED. YOU MUST USE THE",
157 				"-b OPTION TO fsck_ffs TO SPECIFY THE",
158 				"LOCATION OF AN ALTERNATE",
159 				"SUPER-BLOCK TO SUPPLY NEEDED",
160 				"INFORMATION; SEE fsck_ffs(8).");
161 			return(0);
162 		}
163 		doskipclean = 0;
164 		pwarn("USING ALTERNATE SUPERBLOCK AT %d\n", bflag);
165 	}
166 	if (debug)
167 		printf("clean = %d\n", sblock->fs_clean);
168 	if (doswap)
169 		doskipclean = 0;
170 	if (sblock->fs_clean & FS_ISCLEAN) {
171 		if (doskipclean) {
172 			pwarn("%sile system is clean; not checking\n",
173 			    preen ? "f" : "** F");
174 			return (-1);
175 		}
176 		if (!preen && !doswap)
177 			pwarn("** File system is already clean\n");
178 	}
179 	maxfsblock = sblock->fs_size;
180 	maxino = sblock->fs_ncg * sblock->fs_ipg;
181 	sizepb = sblock->fs_bsize;
182 	maxfilesize = sblock->fs_bsize * NDADDR - 1;
183 	for (i = 0; i < NIADDR; i++) {
184 		sizepb *= NINDIR(sblock);
185 		maxfilesize += sizepb;
186 	}
187 	/*
188 	 * Check and potentially fix certain fields in the super block.
189 	 */
190 	if (sblock->fs_optim != FS_OPTTIME && sblock->fs_optim != FS_OPTSPACE) {
191 		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
192 		if (reply("SET TO DEFAULT") == 1) {
193 			sblock->fs_optim = FS_OPTTIME;
194 			sbdirty();
195 		}
196 	}
197 	if ((sblock->fs_minfree < 0 || sblock->fs_minfree > 99)) {
198 		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
199 			sblock->fs_minfree);
200 		if (reply("SET TO DEFAULT") == 1) {
201 			sblock->fs_minfree = 10;
202 			sbdirty();
203 		}
204 	}
205 	if (sblock->fs_postblformat != FS_42POSTBLFMT &&
206 	    (sblock->fs_interleave < 1 ||
207 	    sblock->fs_interleave > sblock->fs_nsect)) {
208 		pwarn("IMPOSSIBLE INTERLEAVE=%d IN SUPERBLOCK",
209 			sblock->fs_interleave);
210 		sblock->fs_interleave = 1;
211 		if (preen)
212 			printf(" (FIXED)\n");
213 		if (preen || reply("SET TO DEFAULT") == 1) {
214 			sbdirty();
215 			dirty(&asblk);
216 		}
217 	}
218 	if (sblock->fs_postblformat != FS_42POSTBLFMT &&
219 	    (sblock->fs_npsect < sblock->fs_nsect ||
220 	    sblock->fs_npsect > sblock->fs_nsect*2)) {
221 		pwarn("IMPOSSIBLE NPSECT=%d IN SUPERBLOCK",
222 			sblock->fs_npsect);
223 		sblock->fs_npsect = sblock->fs_nsect;
224 		if (preen)
225 			printf(" (FIXED)\n");
226 		if (preen || reply("SET TO DEFAULT") == 1) {
227 			sbdirty();
228 			dirty(&asblk);
229 		}
230 	}
231 	if (sblock->fs_bmask != ~(sblock->fs_bsize - 1)) {
232 		pwarn("INCORRECT BMASK=0x%x IN SUPERBLOCK",
233 			sblock->fs_bmask);
234 		sblock->fs_bmask = ~(sblock->fs_bsize - 1);
235 		if (preen)
236 			printf(" (FIXED)\n");
237 		if (preen || reply("FIX") == 1) {
238 			sbdirty();
239 			dirty(&asblk);
240 		}
241 	}
242 	if (sblock->fs_fmask != ~(sblock->fs_fsize - 1)) {
243 		pwarn("INCORRECT FMASK=0x%x IN SUPERBLOCK",
244 			sblock->fs_fmask);
245 		sblock->fs_fmask = ~(sblock->fs_fsize - 1);
246 		if (preen)
247 			printf(" (FIXED)\n");
248 		if (preen || reply("FIX") == 1) {
249 			sbdirty();
250 			dirty(&asblk);
251 		}
252 	}
253 	if (sblock->fs_inodefmt >= FS_44INODEFMT) {
254 		if (sblock->fs_maxfilesize != maxfilesize) {
255 			pwarn("INCORRECT MAXFILESIZE=%lld IN SUPERBLOCK",
256 			    (unsigned long long)sblock->fs_maxfilesize);
257 			sblock->fs_maxfilesize = maxfilesize;
258 			if (preen)
259 				printf(" (FIXED)\n");
260 			if (preen || reply("FIX") == 1) {
261 				sbdirty();
262 				dirty(&asblk);
263 			}
264 		}
265 		if (sblock->fs_maxsymlinklen != MAXSYMLINKLEN) {
266 			pwarn("INCORRECT MAXSYMLINKLEN=%d IN SUPERBLOCK",
267 				sblock->fs_maxsymlinklen);
268 			sblock->fs_maxsymlinklen = MAXSYMLINKLEN;
269 			if (preen)
270 				printf(" (FIXED)\n");
271 			if (preen || reply("FIX") == 1) {
272 				sbdirty();
273 				dirty(&asblk);
274 			}
275 		}
276 		if (sblock->fs_qbmask != ~sblock->fs_bmask) {
277 			pwarn("INCORRECT QBMASK=%llx IN SUPERBLOCK",
278 			    (unsigned long long)sblock->fs_qbmask);
279 			sblock->fs_qbmask = ~sblock->fs_bmask;
280 			if (preen)
281 				printf(" (FIXED)\n");
282 			if (preen || reply("FIX") == 1) {
283 				sbdirty();
284 				dirty(&asblk);
285 			}
286 		}
287 		if (sblock->fs_qfmask != ~sblock->fs_fmask) {
288 			pwarn("INCORRECT QFMASK=%llx IN SUPERBLOCK",
289 			    (unsigned long long)sblock->fs_qfmask);
290 			sblock->fs_qfmask = ~sblock->fs_fmask;
291 			if (preen)
292 				printf(" (FIXED)\n");
293 			if (preen || reply("FIX") == 1) {
294 				sbdirty();
295 				dirty(&asblk);
296 			}
297 		}
298 		newinofmt = 1;
299 	} else {
300 		sblock->fs_qbmask = ~sblock->fs_bmask;
301 		sblock->fs_qfmask = ~sblock->fs_fmask;
302 		newinofmt = 0;
303 	}
304 	/*
305 	 * Convert to new inode format.
306 	 */
307 	if (cvtlevel >= 2 && sblock->fs_inodefmt < FS_44INODEFMT) {
308 		if (preen)
309 			pwarn("CONVERTING TO NEW INODE FORMAT\n");
310 		else if (!reply("CONVERT TO NEW INODE FORMAT"))
311 			return(0);
312 		doinglevel2++;
313 		sblock->fs_inodefmt = FS_44INODEFMT;
314 		sblock->fs_maxfilesize = maxfilesize;
315 		sblock->fs_maxsymlinklen = MAXSYMLINKLEN;
316 		sblock->fs_qbmask = ~sblock->fs_bmask;
317 		sblock->fs_qfmask = ~sblock->fs_fmask;
318 		sbdirty();
319 		dirty(&asblk);
320 	}
321 	/*
322 	 * Convert to new cylinder group format.
323 	 */
324 	if (cvtlevel >= 1 && sblock->fs_postblformat == FS_42POSTBLFMT) {
325 		if (preen)
326 			pwarn("CONVERTING TO NEW CYLINDER GROUP FORMAT\n");
327 		else if (!reply("CONVERT TO NEW CYLINDER GROUP FORMAT"))
328 			return(0);
329 		doinglevel1++;
330 		sblock->fs_postblformat = FS_DYNAMICPOSTBLFMT;
331 		sblock->fs_nrpos = 8;
332 		if (sblock->fs_npsect < sblock->fs_nsect)
333 			sblock->fs_npsect = sblock->fs_nsect;
334 		if (sblock->fs_interleave < 1)
335 			sblock->fs_interleave = 1;
336 		sblock->fs_postbloff =
337 		    (char *)(&sblock->fs_opostbl[0][0]) -
338 		    (char *)(&sblock->fs_firstfield);
339 		sblock->fs_rotbloff = &sblock->fs_space[0] -
340 		    (u_char *)(&sblock->fs_firstfield);
341 		sblock->fs_cgsize =
342 			fragroundup(sblock, CGSIZE(sblock));
343 		sbdirty();
344 		dirty(&asblk);
345 	}
346 	if (asblk.b_dirty && !bflag) {
347 		memmove((struct fs*)sblk.b_un.b_fs, sblock, SBSIZE);
348 		if (needswap)
349 			ffs_sb_swap(sblock, (struct fs*)sblk.b_un.b_fs);
350 		memmove(asblk.b_un.b_fs, sblk.b_un.b_fs, (size_t)sblock->fs_sbsize);
351 		flush(fswritefd, &asblk);
352 	}
353 	/*
354 	 * read in the summary info.
355 	 */
356 	asked = 0;
357 	sblock->fs_csp = (struct csum *)calloc(1, sblock->fs_cssize);
358 	for (i = 0, j = 0; i < sblock->fs_cssize; i += sblock->fs_bsize, j++) {
359 		size = sblock->fs_cssize - i < sblock->fs_bsize ?
360 		    sblock->fs_cssize - i : sblock->fs_bsize;
361 		ccsp = (struct csum *)((char *)sblock->fs_csp + i);
362 		if (bread(fsreadfd, (char *)ccsp,
363 		    fsbtodb(sblock, sblock->fs_csaddr + j * sblock->fs_frag),
364 		    size) != 0 && !asked) {
365 			pfatal("BAD SUMMARY INFORMATION");
366 			if (reply("CONTINUE") == 0) {
367 				markclean = 0;
368 				exit(EEXIT);
369 			}
370 			asked++;
371 		}
372 		if (doswap) {
373 			ffs_csum_swap(ccsp, ccsp, size);
374 			bwrite(fswritefd, (char *)ccsp,
375 			    fsbtodb(sblock,
376 				sblock->fs_csaddr + j * sblock->fs_frag),
377 			    size);
378 		}
379 		if (needswap)
380 			ffs_csum_swap(ccsp, ccsp, size);
381 	}
382 	/*
383 	 * allocate and initialize the necessary maps
384 	 */
385 	bmapsize = roundup(howmany(maxfsblock, NBBY), sizeof(int16_t));
386 	blockmap = calloc((unsigned)bmapsize, sizeof (char));
387 	if (blockmap == NULL) {
388 		printf("cannot alloc %u bytes for blockmap\n",
389 		    (unsigned)bmapsize);
390 		goto badsblabel;
391 	}
392 	statemap = calloc((unsigned)(maxino + 1), sizeof(char));
393 	if (statemap == NULL) {
394 		printf("cannot alloc %u bytes for statemap\n",
395 		    (unsigned)(maxino + 1));
396 		goto badsblabel;
397 	}
398 	typemap = calloc((unsigned)(maxino + 1), sizeof(char));
399 	if (typemap == NULL) {
400 		printf("cannot alloc %u bytes for typemap\n",
401 		    (unsigned)(maxino + 1));
402 		goto badsblabel;
403 	}
404 	lncntp = (int16_t *)calloc((unsigned)(maxino + 1), sizeof(int16_t));
405 	if (lncntp == NULL) {
406 		printf("cannot alloc %u bytes for lncntp\n",
407 		    (unsigned)((maxino + 1) * sizeof(int16_t)));
408 		goto badsblabel;
409 	}
410 	/*
411 	 * cs_ndir may be inaccurate, particularly if we're using the -b
412 	 * option, so set a minimum to prevent bogus subdirectory reconnects
413 	 * and really inefficient directory scans.
414 	 * Also set a maximum in case the value is too large.
415 	 */
416 	numdirs = sblock->fs_cstotal.cs_ndir;
417 	if (numdirs < 1024)
418 		numdirs = 1024;
419 	if (numdirs > maxino + 1)
420 		numdirs = maxino + 1;
421 	inplast = 0;
422 	listmax = numdirs + 10;
423 	inpsort = (struct inoinfo **)calloc((unsigned)listmax,
424 	    sizeof(struct inoinfo *));
425 	inphead = (struct inoinfo **)calloc((unsigned)numdirs,
426 	    sizeof(struct inoinfo *));
427 	if (inpsort == NULL || inphead == NULL) {
428 		printf("cannot alloc %u bytes for inphead\n",
429 		    (unsigned)(numdirs * sizeof(struct inoinfo *)));
430 		goto badsblabel;
431 	}
432 	cgrp = malloc(sblock->fs_cgsize);
433 	if (cgrp == NULL) {
434 		printf("cannot alloc %u bytes for cylinder group\n",
435 		    sblock->fs_cgsize);
436 		goto badsblabel;
437 	}
438 	bufinit();
439 	if (sblock->fs_flags & FS_DOSOFTDEP)
440 		usedsoftdep = 1;
441 	else
442 		usedsoftdep = 0;
443 
444 	{
445 		struct partition *pp = 0;
446 		if (!forceimage && lp)
447 			pp = getdisklabelpart(dev,lp);
448 		if (pp && (pp->p_fstype == FS_APPLEUFS)) {
449 			isappleufs = 1;
450 		}
451 	}
452 	if (readappleufs()) {
453 		isappleufs = 1;
454 	}
455 
456 	dirblksiz = DIRBLKSIZ;
457 	if (isappleufs)
458 		dirblksiz = APPLEUFS_DIRBLKSIZ;
459 
460 	if (debug)
461 		printf("isappleufs = %d, dirblksiz = %d\n", isappleufs, dirblksiz);
462 
463 	return (1);
464 
465 badsblabel:
466 	markclean=0;
467 	ckfini();
468 	return (0);
469 }
470 
471 static int
472 readappleufs()
473 {
474 	ufs_daddr_t label = APPLEUFS_LABEL_OFFSET / dev_bsize;
475 	struct appleufslabel *appleufs;
476 	int i;
477 
478 	/* XXX do we have to deal with APPLEUFS_LABEL_OFFSET not
479 	 * being block aligned (CD's?)
480 	 */
481 	if (bread(fsreadfd, (char *)appleufsblk.b_un.b_fs, label, (long)APPLEUFS_LABEL_SIZE) != 0)
482 		return 0;
483 	appleufsblk.b_bno = label;
484 	appleufsblk.b_size = APPLEUFS_LABEL_SIZE;
485 
486 	appleufs = appleufsblk.b_un.b_appleufs;
487 
488 	if (ntohl(appleufs->ul_magic) != APPLEUFS_LABEL_MAGIC) {
489 		if (!isappleufs) {
490 			return 0;
491 		} else {
492 			pfatal("MISSING APPLEUFS VOLUME LABEL\n");
493 			if (reply("FIX") == 0) {
494 				return 1;
495 			}
496 			ffs_appleufs_set(appleufs,NULL,-1);
497 			appleufsdirty();
498 		}
499 	}
500 
501 	if (ntohl(appleufs->ul_version) != APPLEUFS_LABEL_VERSION) {
502 		pwarn("INCORRECT APPLE UFS VERSION NUMBER (%d should be %d)",
503 			ntohl(appleufs->ul_version),APPLEUFS_LABEL_VERSION);
504 		if (preen) {
505 			printf(" (CORRECTED)\n");
506 		}
507 		if (preen || reply("CORRECT")) {
508 			appleufs->ul_version = htonl(APPLEUFS_LABEL_VERSION);
509 			appleufsdirty();
510 		}
511 	}
512 
513 	if (ntohs(appleufs->ul_namelen) > APPLEUFS_MAX_LABEL_NAME) {
514 		pwarn("APPLE UFS LABEL NAME TOO LONG");
515 		if (preen) {
516 			printf(" (TRUNCATED)\n");
517 		}
518 		if (preen || reply("TRUNCATE")) {
519 			appleufs->ul_namelen = htons(APPLEUFS_MAX_LABEL_NAME);
520 			appleufsdirty();
521 		}
522 	}
523 
524 	if (ntohs(appleufs->ul_namelen) == 0) {
525 		pwarn("MISSING APPLE UFS LABEL NAME");
526 		if (preen) {
527 			printf(" (FIXED)\n");
528 		}
529 		if (preen || reply("FIX")) {
530 			ffs_appleufs_set(appleufs,NULL,-1);
531 			appleufsdirty();
532 		}
533 	}
534 
535 	/* Scan name for first illegal character */
536 	for (i=0;i<ntohs(appleufs->ul_namelen);i++) {
537 		if ((appleufs->ul_name[i] == '\0') ||
538 			(appleufs->ul_name[i] == ':') ||
539 			(appleufs->ul_name[i] == '/')) {
540 			pwarn("APPLE UFS LABEL NAME CONTAINS ILLEGAL CHARACTER");
541 			if (preen) {
542 				printf(" (TRUNCATED)\n");
543 			}
544 			if (preen || reply("TRUNCATE")) {
545 				appleufs->ul_namelen = i+1;
546 				appleufsdirty();
547 			}
548 			break;
549 		}
550 	}
551 
552 	/* Check the checksum last, because if anything else was wrong,
553 	 * then the checksum gets reset anyway.
554 	 */
555 	appleufs->ul_checksum = 0;
556 	appleufs->ul_checksum = ffs_appleufs_cksum(appleufs);
557 	if (appleufsblk.b_un.b_appleufs->ul_checksum != appleufs->ul_checksum) {
558 		pwarn("INVALID APPLE UFS CHECKSUM (%#04x should be %#04x)",
559 			appleufsblk.b_un.b_appleufs->ul_checksum, appleufs->ul_checksum);
560 		if (preen) {
561 			printf(" (CORRECTED)\n");
562 		}
563 		if (preen || reply("CORRECT")) {
564 			appleufsdirty();
565 		} else {
566 			/* put the incorrect checksum back in place */
567 			appleufs->ul_checksum = appleufsblk.b_un.b_appleufs->ul_checksum;
568 		}
569 	}
570 	return 1;
571 }
572 
573 /*
574  * Read in the super block and its summary info.
575  */
576 static int
577 readsb(listerr)
578 	int listerr;
579 {
580 	ufs_daddr_t super = bflag ? bflag : SBOFF / dev_bsize;
581 	struct fs *fs;
582 
583 	if (bread(fsreadfd, (char *)sblk.b_un.b_fs, super, (long)SBSIZE) != 0)
584 		return (0);
585 	sblk.b_bno = super;
586 	sblk.b_size = SBSIZE;
587 
588 	fs = sblk.b_un.b_fs;
589 	/* auto detect byte order */
590 	if( fs->fs_magic == FS_MAGIC) {
591 			if (endian == 0 || BYTE_ORDER == endian) {
592 				needswap = 0;
593 				doswap = do_blkswap = do_dirswap = 0;
594 			} else {
595 				needswap = 1;
596 				doswap = do_blkswap = do_dirswap = 1;
597 			}
598 	} else if (fs->fs_magic == bswap32(FS_MAGIC)) {
599 		if (endian == 0 || BYTE_ORDER != endian) {
600 			needswap = 1;
601 			doswap = do_blkswap = do_dirswap = 0;
602 		} else {
603 			needswap = 0;
604 			doswap = do_blkswap = do_dirswap = 1;
605 		}
606 	} else {
607 		badsb(listerr, "MAGIC NUMBER WRONG");
608 		return (0);
609 	}
610 	if (doswap) {
611 		if (preen)
612 			errx(EEXIT, "incompatible options -B and -p");
613 		if (nflag)
614 			errx(EEXIT, "incompatible options -B and -n");
615 		if (endian == LITTLE_ENDIAN) {
616 			if (!reply("CONVERT TO LITTLE ENDIAN"))
617 				return 0;
618 		} else if (endian == BIG_ENDIAN) {
619 			if (!reply("CONVERT TO BIG ENDIAN"))
620 				return 0;
621 		} else
622 			pfatal("INTERNAL ERROR: unknown endian");
623 	}
624 	if (needswap)
625 		printf("** Swapped byte order\n");
626 	/* swap SB byte order if asked */
627 	if (doswap)
628 		ffs_sb_swap(sblk.b_un.b_fs, sblk.b_un.b_fs);
629 
630 	memmove(sblock, sblk.b_un.b_fs, SBSIZE);
631 	if (needswap)
632 		ffs_sb_swap(sblk.b_un.b_fs, sblock);
633 
634 	/*
635 	 * run a few consistency checks of the super block
636 	 */
637 	if (sblock->fs_ncg < 1)
638 		{ badsb(listerr, "NCG OUT OF RANGE"); return (0); }
639 	if (sblock->fs_cpg < 1)
640 		{ badsb(listerr, "CPG OUT OF RANGE"); return (0); }
641 	if (sblock->fs_ncg * sblock->fs_cpg < sblock->fs_ncyl ||
642 	    (sblock->fs_ncg - 1) * sblock->fs_cpg >= sblock->fs_ncyl)
643 		{ badsb(listerr, "NCYL LESS THAN NCG*CPG"); return (0); }
644 	if (sblock->fs_sbsize > SBSIZE)
645 		{ badsb(listerr, "SIZE PREPOSTEROUSLY LARGE"); return (0); }
646 	/*
647 	 * Compute block size that the filesystem is based on,
648 	 * according to fsbtodb, and adjust superblock block number
649 	 * so we can tell if this is an alternate later.
650 	 */
651 	super *= dev_bsize;
652 	dev_bsize = sblock->fs_fsize / fsbtodb(sblock, 1);
653 	sblk.b_bno = super / dev_bsize;
654 
655 	if (bflag) {
656 		havesb = 1;
657 		return (1);
658 	}
659 	/*
660 	 * Set all possible fields that could differ, then do check
661 	 * of whole super block against an alternate super block.
662 	 * When an alternate super-block is specified this check is skipped.
663 	 */
664 	getblk(&asblk, cgsblock(sblock, sblock->fs_ncg - 1), sblock->fs_sbsize);
665 	if (asblk.b_errs)
666 		return (0);
667 	/* swap SB byte order if asked */
668 	if (doswap)
669 		ffs_sb_swap(asblk.b_un.b_fs, asblk.b_un.b_fs);
670 
671 	memmove(altsblock, asblk.b_un.b_fs, sblock->fs_sbsize);
672 	if (needswap)
673 		ffs_sb_swap(asblk.b_un.b_fs, altsblock);
674 	if (cmpsblks(sblock, altsblock)) {
675 		if (debug) {
676 			long *nlp, *olp, *endlp;
677 
678 			printf("superblock mismatches\n");
679 			nlp = (long *)altsblock;
680 			olp = (long *)sblock;
681 			endlp = olp + (sblock->fs_sbsize / sizeof *olp);
682 			for ( ; olp < endlp; olp++, nlp++) {
683 				if (*olp == *nlp)
684 					continue;
685 				printf("offset %ld, original %lx, alternate %lx\n",
686 				    (long)(olp - (long *)sblock), *olp, *nlp);
687 			}
688 		}
689 		badsb(listerr,
690 		"VALUES IN SUPER BLOCK DISAGREE WITH THOSE IN FIRST ALTERNATE");
691 		return (0);
692 	}
693 	/* Now we know the SB is valid, we can write it back if needed */
694 	if (doswap) {
695 		sbdirty();
696 		dirty(&asblk);
697 	}
698 	havesb = 1;
699 	return (1);
700 }
701 
702 int
703 cmpsblks(const struct fs *sb, struct fs *asb)
704 {
705 
706 	/*
707 	 * Copy fields which we don't care if they're different in the
708 	 * alternate superblocks, as they're either likely to be
709 	 * different because they're per-cylinder-group specific, or
710 	 * because they're transient details which are only maintained
711 	 * in the primary superblock.
712 	 */
713 	asb->fs_firstfield = sb->fs_firstfield;
714 	asb->fs_unused_1 = sb->fs_unused_1;
715 	asb->fs_time = sb->fs_time;
716 	asb->fs_cstotal = sb->fs_cstotal;
717 	asb->fs_cgrotor = sb->fs_cgrotor;
718 	asb->fs_fmod = sb->fs_fmod;
719 	asb->fs_clean = sb->fs_clean;
720 	asb->fs_ronly = sb->fs_ronly;
721 	asb->fs_flags = sb->fs_flags;
722 	asb->fs_maxcontig = sb->fs_maxcontig;
723 	asb->fs_minfree = sb->fs_minfree;
724 	asb->fs_optim = sb->fs_optim;
725 	asb->fs_rotdelay = sb->fs_rotdelay;
726 	asb->fs_maxbpg = sb->fs_maxbpg;
727 	memmove(asb->fs_ocsp, sb->fs_ocsp, sizeof sb->fs_ocsp);
728 	asb->fs_contigdirs = sb->fs_contigdirs;
729 	asb->fs_csp = sb->fs_csp;
730 	asb->fs_maxcluster = sb->fs_maxcluster;
731 	memmove(asb->fs_fsmnt, sb->fs_fsmnt, sizeof sb->fs_fsmnt);
732 	memmove(asb->fs_snapinum,
733 		sb->fs_snapinum, sizeof sb->fs_snapinum);
734 	asb->fs_avgfilesize = sb->fs_avgfilesize;
735 	asb->fs_avgfpdir = sb->fs_avgfpdir;
736 	asb->fs_pendingblocks = sb->fs_pendingblocks;
737 	asb->fs_pendinginodes = sb->fs_pendinginodes;
738 	memmove(asb->fs_sparecon,
739 		sb->fs_sparecon, sizeof sb->fs_sparecon);
740 	/*
741 	 * The following should not have to be copied, but need to be.
742 	 */
743 	asb->fs_fsbtodb = sb->fs_fsbtodb;
744 	asb->fs_interleave = sb->fs_interleave;
745 	asb->fs_npsect = sb->fs_npsect;
746 	asb->fs_nrpos = sb->fs_nrpos;
747 	asb->fs_qbmask = sb->fs_qbmask;
748 	asb->fs_qfmask = sb->fs_qfmask;
749 	asb->fs_state = sb->fs_state;
750 	asb->fs_maxfilesize = sb->fs_maxfilesize;
751 
752 	/*
753 	 * Compare the superblocks, effectively checking every other
754 	 * field to see if they differ.
755 	 */
756 	return (memcmp(sb, asb, (int)sb->fs_sbsize));
757 }
758 
759 static void
760 badsb(listerr, s)
761 	int listerr;
762 	char *s;
763 {
764 
765 	if (!listerr)
766 		return;
767 	if (preen)
768 		printf("%s: ", cdevname());
769 	pfatal("BAD SUPER BLOCK: %s\n", s);
770 }
771 
772 /*
773  * Calculate a prototype superblock based on information in the disk label.
774  * When done the cgsblock macro can be calculated and the fs_ncg field
775  * can be used. Do NOT attempt to use other macros without verifying that
776  * their needed information is available!
777  */
778 static int
779 calcsb(dev, devfd, fs)
780 	const char *dev;
781 	int devfd;
782 	struct fs *fs;
783 {
784 	struct disklabel *lp;
785 	struct partition *pp;
786 	int i;
787 
788 	lp = getdisklabel(dev, devfd);
789 	pp = getdisklabelpart(dev,lp);
790 	if (pp == 0) {
791 		pfatal("%s: CANNOT FIGURE OUT FILE SYSTEM PARTITION\n", dev);
792 		return (0);
793 	}
794 	if ((pp->p_fstype != FS_BSDFFS) && (pp->p_fstype != FS_APPLEUFS)) {
795 		pfatal("%s: NOT LABELED AS A BSD FILE SYSTEM (%s)\n",
796 			dev, pp->p_fstype < FSMAXTYPES ?
797 			fstypenames[pp->p_fstype] : "unknown");
798 		return (0);
799 	}
800 	/* avoid divide by 0 */
801 	if (pp->p_fsize == 0 || pp->p_frag == 0)
802 		return (0);
803 	memset(fs, 0, sizeof(struct fs));
804 	fs->fs_fsize = pp->p_fsize;
805 	fs->fs_frag = pp->p_frag;
806 	fs->fs_cpg = pp->p_cpg;
807 	fs->fs_size = pp->p_size;
808 	fs->fs_ntrak = lp->d_ntracks;
809 	fs->fs_nsect = lp->d_nsectors;
810 	fs->fs_spc = lp->d_secpercyl;
811 	fs->fs_nspf = fs->fs_fsize / lp->d_secsize;
812 	fs->fs_sblkno = roundup(
813 		howmany(lp->d_bbsize + lp->d_sbsize, fs->fs_fsize),
814 		fs->fs_frag);
815 	fs->fs_cgmask = 0xffffffff;
816 	for (i = fs->fs_ntrak; i > 1; i >>= 1)
817 		fs->fs_cgmask <<= 1;
818 	if (!POWEROF2(fs->fs_ntrak))
819 		fs->fs_cgmask <<= 1;
820 	fs->fs_cgoffset = roundup(
821 		howmany(fs->fs_nsect, NSPF(fs)), fs->fs_frag);
822 	fs->fs_fpg = (fs->fs_cpg * fs->fs_spc) / NSPF(fs);
823 	fs->fs_ncg = howmany(fs->fs_size / fs->fs_spc, fs->fs_cpg);
824 	for (fs->fs_fsbtodb = 0, i = NSPF(fs); i > 1; i >>= 1)
825 		fs->fs_fsbtodb++;
826 	dev_bsize = lp->d_secsize;
827 	return (1);
828 }
829 
830 static struct disklabel *
831 getdisklabel(s, fd)
832 	const char *s;
833 	int	fd;
834 {
835 	static struct disklabel lab;
836 
837 	if (ioctl(fd, DIOCGDINFO, (char *)&lab) < 0) {
838 		if (s == NULL)
839 			return ((struct disklabel *)NULL);
840 		pwarn("ioctl (GCINFO): %s\n", strerror(errno));
841 		errx(EEXIT, "%s: can't read disk label", s);
842 	}
843 	return (&lab);
844 }
845 
846 static struct partition *
847 getdisklabelpart(dev, lp)
848 	const char *dev;
849 	struct disklabel *lp;
850 {
851 	char *cp;
852 
853 	cp = strchr(dev, '\0') - 1;
854 	if ((cp == (char *)-1 || (*cp < 'a' || *cp > 'p')) && !isdigit(*cp)) {
855 		return 0;
856 	}
857 	if (isdigit(*cp))
858 		return &lp->d_partitions[0];
859 	else
860 		return &lp->d_partitions[*cp - 'a'];
861 }
862 
863