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setup.c revision 1.79
      1 /*	$NetBSD: setup.c,v 1.79 2006/03/17 15:53:46 rumble 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. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 #if 0
     35 static char sccsid[] = "@(#)setup.c	8.10 (Berkeley) 5/9/95";
     36 #else
     37 __RCSID("$NetBSD: setup.c,v 1.79 2006/03/17 15:53:46 rumble Exp $");
     38 #endif
     39 #endif /* not lint */
     40 
     41 #include <sys/param.h>
     42 #include <sys/time.h>
     43 #include <sys/stat.h>
     44 #include <sys/ioctl.h>
     45 #define FSTYPENAMES
     46 #include <sys/disklabel.h>
     47 #include <sys/file.h>
     48 
     49 #include <ufs/ufs/dinode.h>
     50 #include <ufs/ufs/dir.h>
     51 #include <ufs/ufs/ufs_bswap.h>
     52 #include <ufs/ffs/fs.h>
     53 #include <ufs/ffs/ffs_extern.h>
     54 
     55 #include <ctype.h>
     56 #include <err.h>
     57 #include <errno.h>
     58 #include <stdio.h>
     59 #include <stdlib.h>
     60 #include <string.h>
     61 
     62 #include "fsck.h"
     63 #include "extern.h"
     64 #include "fsutil.h"
     65 
     66 #define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
     67 
     68 static void badsb(int, const char *);
     69 static int calcsb(const char *, int, struct fs *);
     70 static struct disklabel *getdisklabel(const char *, int);
     71 static struct partition *getdisklabelpart(const char *, struct disklabel *);
     72 static int readsb(int);
     73 static int readappleufs(void);
     74 
     75 int16_t sblkpostbl[256];
     76 
     77 /*
     78  * Read in a superblock finding an alternate if necessary.
     79  * Return 1 if successful, 0 if unsuccessful, -1 if filesystem
     80  * is already clean (preen mode only).
     81  */
     82 int
     83 setup(const char *dev)
     84 {
     85 	long cg, size, asked, i, j;
     86 	long bmapsize;
     87 	struct disklabel *lp = NULL;
     88 	off_t sizepb;
     89 	struct stat statb;
     90 	struct fs proto;
     91 	int doskipclean;
     92 	u_int64_t maxfilesize;
     93 	struct csum *ccsp;
     94 
     95 	havesb = 0;
     96 	fswritefd = -1;
     97 	doskipclean = skipclean;
     98 	if (stat(dev, &statb) < 0) {
     99 		printf("Can't stat %s: %s\n", dev, strerror(errno));
    100 		return (0);
    101 	}
    102 	if (!forceimage && !S_ISCHR(statb.st_mode)) {
    103 		pfatal("%s is not a character device", dev);
    104 		if (reply("CONTINUE") == 0)
    105 			return (0);
    106 	}
    107 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
    108 		printf("Can't open %s: %s\n", dev, strerror(errno));
    109 		return (0);
    110 	}
    111 	if (nflag || (fswritefd = open(dev, O_WRONLY)) < 0) {
    112 		fswritefd = -1;
    113 		if (preen)
    114 			pfatal("NO WRITE ACCESS");
    115 		printf("** %s (NO WRITE)\n", dev);
    116 		quiet = 0;
    117 	} else
    118 		if (!preen && !quiet)
    119 			printf("** %s\n", dev);
    120 	fsmodified = 0;
    121 	lfdir = 0;
    122 	initbarea(&sblk);
    123 	initbarea(&asblk);
    124 	sblk.b_un.b_buf = malloc(SBLOCKSIZE);
    125 	sblock = malloc(SBLOCKSIZE);
    126 	asblk.b_un.b_buf = malloc(SBLOCKSIZE);
    127 	altsblock = malloc(SBLOCKSIZE);
    128 	if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL ||
    129 		sblock == NULL || altsblock == NULL)
    130 		errx(EEXIT, "cannot allocate space for superblock");
    131 	if (!forceimage && (lp = getdisklabel(NULL, fsreadfd)) != NULL)
    132 		dev_bsize = secsize = lp->d_secsize;
    133 	else
    134 		dev_bsize = secsize = DEV_BSIZE;
    135 	/*
    136 	 * Read in the superblock, looking for alternates if necessary
    137 	 */
    138 	if (readsb(1) == 0) {
    139 		if (bflag || preen || forceimage ||
    140 		    calcsb(dev, fsreadfd, &proto) == 0)
    141 			return(0);
    142 		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
    143 			return (0);
    144 		for (cg = 0; cg < proto.fs_ncg; cg++) {
    145 			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
    146 			if (readsb(0) != 0)
    147 				break;
    148 		}
    149 		if (cg >= proto.fs_ncg) {
    150 			printf("%s %s\n%s %s\n%s %s\n",
    151 				"SEARCH FOR ALTERNATE SUPER-BLOCK",
    152 				"FAILED. YOU MUST USE THE",
    153 				"-b OPTION TO fsck_ffs TO SPECIFY THE",
    154 				"LOCATION OF AN ALTERNATE",
    155 				"SUPER-BLOCK TO SUPPLY NEEDED",
    156 				"INFORMATION; SEE fsck_ffs(8).");
    157 			return(0);
    158 		}
    159 		doskipclean = 0;
    160 		pwarn("USING ALTERNATE SUPERBLOCK AT %d\n", bflag);
    161 	}
    162 	if (debug)
    163 		printf("clean = %d\n", sblock->fs_clean);
    164 	if (doswap)
    165 		doskipclean = 0;
    166 	if (sblock->fs_clean & FS_ISCLEAN) {
    167 		if (doskipclean) {
    168 			if (!quiet)
    169 				pwarn("%sile system is clean; not checking\n",
    170 				    preen ? "f" : "** F");
    171 			return (-1);
    172 		}
    173 		if (!preen && !doswap)
    174 			pwarn("** File system is already clean\n");
    175 	}
    176 	maxfsblock = sblock->fs_size;
    177 	maxino = sblock->fs_ncg * sblock->fs_ipg;
    178 	sizepb = sblock->fs_bsize;
    179 	maxfilesize = sblock->fs_bsize * NDADDR - 1;
    180 	for (i = 0; i < NIADDR; i++) {
    181 		sizepb *= NINDIR(sblock);
    182 		maxfilesize += sizepb;
    183 	}
    184 	if ((!is_ufs2 && cvtlevel >= 4) &&
    185 			(sblock->fs_old_flags & FS_FLAGS_UPDATED) == 0) {
    186 		if (preen)
    187 			pwarn("CONVERTING TO NEW SUPERBLOCK LAYOUT\n");
    188 		else if (!reply("CONVERT TO NEW SUPERBLOCK LAYOUT"))
    189 			return(0);
    190 		sblock->fs_old_flags |= FS_FLAGS_UPDATED;
    191 		/* Disable the postbl tables */
    192 		sblock->fs_old_cpc = 0;
    193 		sblock->fs_old_nrpos = 1;
    194 		sblock->fs_old_trackskew = 0;
    195 		/* The other fields have already been updated by
    196 		 * sb_oldfscompat_read
    197 		 */
    198 		sbdirty();
    199 	}
    200 	if (!is_ufs2 && cvtlevel == 3 &&
    201 	    (sblock->fs_old_flags & FS_FLAGS_UPDATED)) {
    202 		if (preen)
    203 			pwarn("DOWNGRADING TO OLD SUPERBLOCK LAYOUT\n");
    204 		else if (!reply("DOWNGRADE TO OLD SUPERBLOCK LAYOUT"))
    205 			return(0);
    206 		sblock->fs_old_flags &= ~FS_FLAGS_UPDATED;
    207 		sb_oldfscompat_write(sblock, sblock);
    208 		sblock->fs_old_flags &= ~FS_FLAGS_UPDATED; /* just in case */
    209 		/* Leave postbl tables disabled, but blank its superblock region anyway */
    210 		sblock->fs_old_postblformat = FS_DYNAMICPOSTBLFMT;
    211 		sblock->fs_old_cpc = 0;
    212 		sblock->fs_old_nrpos = 1;
    213 		sblock->fs_old_trackskew = 0;
    214 		memset(&sblock->fs_old_postbl_start, 0xff, 256);
    215 		sb_oldfscompat_read(sblock, &sblocksave);
    216 		sbdirty();
    217 	}
    218 	/*
    219 	 * Check and potentially fix certain fields in the super block.
    220 	 */
    221 	if (sblock->fs_optim != FS_OPTTIME && sblock->fs_optim != FS_OPTSPACE) {
    222 		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
    223 		if (reply("SET TO DEFAULT") == 1) {
    224 			sblock->fs_optim = FS_OPTTIME;
    225 			sbdirty();
    226 		}
    227 	}
    228 	if ((sblock->fs_minfree < 0 || sblock->fs_minfree > 99)) {
    229 		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
    230 			sblock->fs_minfree);
    231 		if (reply("SET TO DEFAULT") == 1) {
    232 			sblock->fs_minfree = 10;
    233 			sbdirty();
    234 		}
    235 	}
    236 	if (!is_ufs2 && sblock->fs_old_postblformat != FS_42POSTBLFMT &&
    237 	    (sblock->fs_old_interleave < 1 ||
    238 	    sblock->fs_old_interleave > sblock->fs_old_nsect)) {
    239 		pwarn("IMPOSSIBLE INTERLEAVE=%d IN SUPERBLOCK",
    240 			sblock->fs_old_interleave);
    241 		sblock->fs_old_interleave = 1;
    242 		if (preen)
    243 			printf(" (FIXED)\n");
    244 		if (preen || reply("SET TO DEFAULT") == 1) {
    245 			sbdirty();
    246 			dirty(&asblk);
    247 		}
    248 	}
    249 	if (!is_ufs2 && sblock->fs_old_postblformat != FS_42POSTBLFMT &&
    250 	    (sblock->fs_old_npsect < sblock->fs_old_nsect ||
    251 	    sblock->fs_old_npsect > sblock->fs_old_nsect*2)) {
    252 		pwarn("IMPOSSIBLE NPSECT=%d IN SUPERBLOCK",
    253 			sblock->fs_old_npsect);
    254 		sblock->fs_old_npsect = sblock->fs_old_nsect;
    255 		if (preen)
    256 			printf(" (FIXED)\n");
    257 		if (preen || reply("SET TO DEFAULT") == 1) {
    258 			sbdirty();
    259 			dirty(&asblk);
    260 		}
    261 	}
    262 	if (sblock->fs_bmask != ~(sblock->fs_bsize - 1)) {
    263 		pwarn("INCORRECT BMASK=0x%x IN SUPERBLOCK",
    264 			sblock->fs_bmask);
    265 		sblock->fs_bmask = ~(sblock->fs_bsize - 1);
    266 		if (preen)
    267 			printf(" (FIXED)\n");
    268 		if (preen || reply("FIX") == 1) {
    269 			sbdirty();
    270 			dirty(&asblk);
    271 		}
    272 	}
    273 	if (sblock->fs_fmask != ~(sblock->fs_fsize - 1)) {
    274 		pwarn("INCORRECT FMASK=0x%x IN SUPERBLOCK",
    275 			sblock->fs_fmask);
    276 		sblock->fs_fmask = ~(sblock->fs_fsize - 1);
    277 		if (preen)
    278 			printf(" (FIXED)\n");
    279 		if (preen || reply("FIX") == 1) {
    280 			sbdirty();
    281 			dirty(&asblk);
    282 		}
    283 	}
    284 	if (is_ufs2 || sblock->fs_old_inodefmt >= FS_44INODEFMT) {
    285 		if (sblock->fs_maxfilesize != maxfilesize) {
    286 			pwarn("INCORRECT MAXFILESIZE=%lld IN SUPERBLOCK",
    287 			    (unsigned long long)sblock->fs_maxfilesize);
    288 			sblock->fs_maxfilesize = maxfilesize;
    289 			if (preen)
    290 				printf(" (FIXED)\n");
    291 			if (preen || reply("FIX") == 1) {
    292 				sbdirty();
    293 				dirty(&asblk);
    294 			}
    295 		}
    296 		if ((is_ufs2 && sblock->fs_maxsymlinklen != MAXSYMLINKLEN_UFS2)
    297 		    ||
    298 		   (!is_ufs2 && sblock->fs_maxsymlinklen != MAXSYMLINKLEN_UFS1))
    299 		    {
    300 			pwarn("INCORRECT MAXSYMLINKLEN=%d IN SUPERBLOCK",
    301 				sblock->fs_maxsymlinklen);
    302 			sblock->fs_maxsymlinklen = is_ufs2 ?
    303 			    MAXSYMLINKLEN_UFS2 : MAXSYMLINKLEN_UFS1;
    304 			if (preen)
    305 				printf(" (FIXED)\n");
    306 			if (preen || reply("FIX") == 1) {
    307 				sbdirty();
    308 				dirty(&asblk);
    309 			}
    310 		}
    311 		if (sblock->fs_qbmask != ~sblock->fs_bmask) {
    312 			pwarn("INCORRECT QBMASK=%#llx IN SUPERBLOCK",
    313 			    (unsigned long long)sblock->fs_qbmask);
    314 			sblock->fs_qbmask = ~sblock->fs_bmask;
    315 			if (preen)
    316 				printf(" (FIXED)\n");
    317 			if (preen || reply("FIX") == 1) {
    318 				sbdirty();
    319 				dirty(&asblk);
    320 			}
    321 		}
    322 		if (sblock->fs_qfmask != ~sblock->fs_fmask) {
    323 			pwarn("INCORRECT QFMASK=%#llx IN SUPERBLOCK",
    324 			    (unsigned long long)sblock->fs_qfmask);
    325 			sblock->fs_qfmask = ~sblock->fs_fmask;
    326 			if (preen)
    327 				printf(" (FIXED)\n");
    328 			if (preen || reply("FIX") == 1) {
    329 				sbdirty();
    330 				dirty(&asblk);
    331 			}
    332 		}
    333 		newinofmt = 1;
    334 	} else {
    335 		sblock->fs_qbmask = ~sblock->fs_bmask;
    336 		sblock->fs_qfmask = ~sblock->fs_fmask;
    337 		newinofmt = 0;
    338 	}
    339 	/*
    340 	 * Convert to new inode format.
    341 	 */
    342 	if (!is_ufs2 && cvtlevel >= 2 &&
    343 	    sblock->fs_old_inodefmt < FS_44INODEFMT) {
    344 		if (preen)
    345 			pwarn("CONVERTING TO NEW INODE FORMAT\n");
    346 		else if (!reply("CONVERT TO NEW INODE FORMAT"))
    347 			return(0);
    348 		doinglevel2++;
    349 		sblock->fs_old_inodefmt = FS_44INODEFMT;
    350 		sblock->fs_maxfilesize = maxfilesize;
    351 		sblock->fs_maxsymlinklen = MAXSYMLINKLEN_UFS1;
    352 		sblock->fs_qbmask = ~sblock->fs_bmask;
    353 		sblock->fs_qfmask = ~sblock->fs_fmask;
    354 		sbdirty();
    355 		dirty(&asblk);
    356 	}
    357 	/*
    358 	 * Convert to new cylinder group format.
    359 	 */
    360 	if (!is_ufs2 && cvtlevel >= 1 &&
    361 	    sblock->fs_old_postblformat == FS_42POSTBLFMT) {
    362 		if (preen)
    363 			pwarn("CONVERTING TO NEW CYLINDER GROUP FORMAT\n");
    364 		else if (!reply("CONVERT TO NEW CYLINDER GROUP FORMAT"))
    365 			return(0);
    366 		doinglevel1++;
    367 		sblock->fs_old_postblformat = FS_DYNAMICPOSTBLFMT;
    368 		sblock->fs_old_nrpos = 8;
    369 		sblock->fs_old_postbloff =
    370 		    (char *)(&sblock->fs_old_postbl_start) -
    371 		    (char *)(&sblock->fs_firstfield);
    372 		sblock->fs_old_rotbloff =
    373 				(char *)(&sblock->fs_magic+1) -
    374 				(char *)(&sblock->fs_firstfield);
    375 		sblock->fs_cgsize =
    376 			fragroundup(sblock, CGSIZE(sblock));
    377 		sbdirty();
    378 		dirty(&asblk);
    379 	}
    380 	if (asblk.b_dirty && !bflag) {
    381 		memmove(sblk.b_un.b_fs, sblock, SBLOCKSIZE);
    382 		sb_oldfscompat_write(sblk.b_un.b_fs, sblocksave);
    383 		if (needswap)
    384 			ffs_sb_swap(sblk.b_un.b_fs, sblk.b_un.b_fs);
    385 		memmove(asblk.b_un.b_fs, sblk.b_un.b_fs, (size_t)sblock->fs_sbsize);
    386 		flush(fswritefd, &asblk);
    387 	}
    388 	/*
    389 	 * read in the summary info.
    390 	 */
    391 	asked = 0;
    392 	sblock->fs_csp = (struct csum *)calloc(1, sblock->fs_cssize);
    393 	if (sblock->fs_csp == NULL) {
    394 		pwarn("cannot alloc %u bytes for summary info\n",
    395 		    sblock->fs_cssize);
    396 		goto badsblabel;
    397 	}
    398 	for (i = 0, j = 0; i < sblock->fs_cssize; i += sblock->fs_bsize, j++) {
    399 		size = sblock->fs_cssize - i < sblock->fs_bsize ?
    400 		    sblock->fs_cssize - i : sblock->fs_bsize;
    401 		ccsp = (struct csum *)((char *)sblock->fs_csp + i);
    402 		if (bread(fsreadfd, (char *)ccsp,
    403 		    fsbtodb(sblock, sblock->fs_csaddr + j * sblock->fs_frag),
    404 		    size) != 0 && !asked) {
    405 			pfatal("BAD SUMMARY INFORMATION");
    406 			if (reply("CONTINUE") == 0) {
    407 				markclean = 0;
    408 				exit(EEXIT);
    409 			}
    410 			asked++;
    411 		}
    412 		if (doswap) {
    413 			ffs_csum_swap(ccsp, ccsp, size);
    414 			bwrite(fswritefd, (char *)ccsp,
    415 			    fsbtodb(sblock,
    416 				sblock->fs_csaddr + j * sblock->fs_frag),
    417 			    size);
    418 		}
    419 		if (needswap)
    420 			ffs_csum_swap(ccsp, ccsp, size);
    421 	}
    422 	/*
    423 	 * allocate and initialize the necessary maps
    424 	 */
    425 	bmapsize = roundup(howmany(maxfsblock, NBBY), sizeof(int16_t));
    426 	blockmap = calloc((unsigned)bmapsize, sizeof (char));
    427 	if (blockmap == NULL) {
    428 		pwarn("cannot alloc %u bytes for blockmap\n",
    429 		    (unsigned)bmapsize);
    430 		goto badsblabel;
    431 	}
    432 	inostathead = calloc((unsigned)(sblock->fs_ncg),
    433 	    sizeof(struct inostatlist));
    434 	if (inostathead == NULL) {
    435 		pwarn("cannot alloc %u bytes for inostathead\n",
    436 		    (unsigned)(sizeof(struct inostatlist) * (sblock->fs_ncg)));
    437 		goto badsblabel;
    438 	}
    439 	/*
    440 	 * cs_ndir may be inaccurate, particularly if we're using the -b
    441 	 * option, so set a minimum to prevent bogus subdirectory reconnects
    442 	 * and really inefficient directory scans.
    443 	 * Also set a maximum in case the value is too large.
    444 	 */
    445 	numdirs = sblock->fs_cstotal.cs_ndir;
    446 	if (numdirs < 1024)
    447 		numdirs = 1024;
    448 	if (numdirs > maxino + 1)
    449 		numdirs = maxino + 1;
    450 	dirhash = numdirs;
    451 	inplast = 0;
    452 	listmax = numdirs + 10;
    453 	inpsort = (struct inoinfo **)calloc((unsigned)listmax,
    454 	    sizeof(struct inoinfo *));
    455 	inphead = (struct inoinfo **)calloc((unsigned)numdirs,
    456 	    sizeof(struct inoinfo *));
    457 	if (inpsort == NULL || inphead == NULL) {
    458 		pwarn("cannot alloc %u bytes for inphead\n",
    459 		    (unsigned)(numdirs * sizeof(struct inoinfo *)));
    460 		goto badsblabel;
    461 	}
    462 	cgrp = malloc(sblock->fs_cgsize);
    463 	if (cgrp == NULL) {
    464 		pwarn("cannot alloc %u bytes for cylinder group\n",
    465 		    sblock->fs_cgsize);
    466 		goto badsblabel;
    467 	}
    468 	bufinit();
    469 	if (sblock->fs_flags & FS_DOSOFTDEP)
    470 		usedsoftdep = 1;
    471 	else
    472 		usedsoftdep = 0;
    473 
    474 	{
    475 		struct partition *pp = 0;
    476 		if (!forceimage && lp)
    477 			pp = getdisklabelpart(dev,lp);
    478 		if (pp && (pp->p_fstype == FS_APPLEUFS)) {
    479 			isappleufs = 1;
    480 		}
    481 	}
    482 	if (readappleufs()) {
    483 		isappleufs = 1;
    484 	}
    485 
    486 	dirblksiz = DIRBLKSIZ;
    487 	if (isappleufs)
    488 		dirblksiz = APPLEUFS_DIRBLKSIZ;
    489 
    490 	if (debug)
    491 		printf("isappleufs = %d, dirblksiz = %d\n", isappleufs, dirblksiz);
    492 
    493 	return (1);
    494 
    495 badsblabel:
    496 	markclean=0;
    497 	ckfini();
    498 	return (0);
    499 }
    500 
    501 static int
    502 readappleufs(void)
    503 {
    504 	daddr_t label = APPLEUFS_LABEL_OFFSET / dev_bsize;
    505 	struct appleufslabel *appleufs;
    506 	int i;
    507 
    508 	/* XXX do we have to deal with APPLEUFS_LABEL_OFFSET not
    509 	 * being block aligned (CD's?)
    510 	 */
    511 	if (bread(fsreadfd, (char *)appleufsblk.b_un.b_fs, label,
    512 	    (long)APPLEUFS_LABEL_SIZE) != 0)
    513 		return 0;
    514 	appleufsblk.b_bno = label;
    515 	appleufsblk.b_size = APPLEUFS_LABEL_SIZE;
    516 
    517 	appleufs = appleufsblk.b_un.b_appleufs;
    518 
    519 	if (ntohl(appleufs->ul_magic) != APPLEUFS_LABEL_MAGIC) {
    520 		if (!isappleufs) {
    521 			return 0;
    522 		} else {
    523 			pfatal("MISSING APPLEUFS VOLUME LABEL\n");
    524 			if (reply("FIX") == 0) {
    525 				return 1;
    526 			}
    527 			ffs_appleufs_set(appleufs, NULL, -1, 0);
    528 			appleufsdirty();
    529 		}
    530 	}
    531 
    532 	if (ntohl(appleufs->ul_version) != APPLEUFS_LABEL_VERSION) {
    533 		pwarn("INCORRECT APPLE UFS VERSION NUMBER (%d should be %d)",
    534 			ntohl(appleufs->ul_version),APPLEUFS_LABEL_VERSION);
    535 		if (preen) {
    536 			printf(" (CORRECTED)\n");
    537 		}
    538 		if (preen || reply("CORRECT")) {
    539 			appleufs->ul_version = htonl(APPLEUFS_LABEL_VERSION);
    540 			appleufsdirty();
    541 		}
    542 	}
    543 
    544 	if (ntohs(appleufs->ul_namelen) > APPLEUFS_MAX_LABEL_NAME) {
    545 		pwarn("APPLE UFS LABEL NAME TOO LONG");
    546 		if (preen) {
    547 			printf(" (TRUNCATED)\n");
    548 		}
    549 		if (preen || reply("TRUNCATE")) {
    550 			appleufs->ul_namelen = htons(APPLEUFS_MAX_LABEL_NAME);
    551 			appleufsdirty();
    552 		}
    553 	}
    554 
    555 	if (ntohs(appleufs->ul_namelen) == 0) {
    556 		pwarn("MISSING APPLE UFS LABEL NAME");
    557 		if (preen) {
    558 			printf(" (FIXED)\n");
    559 		}
    560 		if (preen || reply("FIX")) {
    561 			ffs_appleufs_set(appleufs, NULL, -1, 0);
    562 			appleufsdirty();
    563 		}
    564 	}
    565 
    566 	/* Scan name for first illegal character */
    567 	for (i=0;i<ntohs(appleufs->ul_namelen);i++) {
    568 		if ((appleufs->ul_name[i] == '\0') ||
    569 			(appleufs->ul_name[i] == ':') ||
    570 			(appleufs->ul_name[i] == '/')) {
    571 			pwarn("APPLE UFS LABEL NAME CONTAINS ILLEGAL CHARACTER");
    572 			if (preen) {
    573 				printf(" (TRUNCATED)\n");
    574 			}
    575 			if (preen || reply("TRUNCATE")) {
    576 				appleufs->ul_namelen = i+1;
    577 				appleufsdirty();
    578 			}
    579 			break;
    580 		}
    581 	}
    582 
    583 	/* Check the checksum last, because if anything else was wrong,
    584 	 * then the checksum gets reset anyway.
    585 	 */
    586 	appleufs->ul_checksum = 0;
    587 	appleufs->ul_checksum = ffs_appleufs_cksum(appleufs);
    588 	if (appleufsblk.b_un.b_appleufs->ul_checksum != appleufs->ul_checksum) {
    589 		pwarn("INVALID APPLE UFS CHECKSUM (%#04x should be %#04x)",
    590 			appleufsblk.b_un.b_appleufs->ul_checksum, appleufs->ul_checksum);
    591 		if (preen) {
    592 			printf(" (CORRECTED)\n");
    593 		}
    594 		if (preen || reply("CORRECT")) {
    595 			appleufsdirty();
    596 		} else {
    597 			/* put the incorrect checksum back in place */
    598 			appleufs->ul_checksum = appleufsblk.b_un.b_appleufs->ul_checksum;
    599 		}
    600 	}
    601 	return 1;
    602 }
    603 
    604 /*
    605  * Detect byte order. Return 0 if valid magic found, -1 otherwise.
    606  */
    607 static int
    608 detect_byteorder(struct fs *fs, int sblockoff)
    609 {
    610 	if (sblockoff == SBLOCK_UFS2 && (fs->fs_magic == FS_UFS1_MAGIC ||
    611 	    fs->fs_magic == bswap32(FS_UFS1_MAGIC)))
    612 		/* Likely to be the first alternate of a fs with 64k blocks */
    613 		return -1;
    614 	if (fs->fs_magic == FS_UFS1_MAGIC || fs->fs_magic == FS_UFS2_MAGIC) {
    615 		if (endian == 0 || BYTE_ORDER == endian) {
    616 			needswap = 0;
    617 			doswap = do_blkswap = do_dirswap = 0;
    618 		} else {
    619 			needswap = 1;
    620 			doswap = do_blkswap = do_dirswap = 1;
    621 		}
    622 		return 0;
    623 	} else if (fs->fs_magic == bswap32(FS_UFS1_MAGIC) ||
    624 		   fs->fs_magic == bswap32(FS_UFS2_MAGIC)) {
    625 		if (endian == 0 || BYTE_ORDER != endian) {
    626 			needswap = 1;
    627 			doswap = do_blkswap = do_dirswap = 0;
    628 		} else {
    629 			needswap = 0;
    630 			doswap = do_blkswap = do_dirswap = 1;
    631 		}
    632 		return 0;
    633 	}
    634 	return -1;
    635 }
    636 
    637 /*
    638  * Possible superblock locations ordered from most to least likely.
    639  */
    640 static off_t sblock_try[] = SBLOCKSEARCH;
    641 
    642 /*
    643  * Read in the super block and its summary info.
    644  */
    645 static int
    646 readsb(int listerr)
    647 {
    648 	daddr_t super = 0;
    649 	struct fs *fs;
    650 	int i;
    651 
    652 	if (bflag) {
    653 		super = bflag;
    654 		if (bread(fsreadfd, (char *)sblk.b_un.b_fs, super,
    655 		    (long)SBLOCKSIZE) != 0)
    656 			return (0);
    657 		fs = sblk.b_un.b_fs;
    658 		if (detect_byteorder(fs, -1) < 0) {
    659 			badsb(listerr, "MAGIC NUMBER WRONG");
    660 			return (0);
    661 		}
    662 	} else {
    663 		for (i = 0; sblock_try[i] != -1; i++) {
    664 			super = sblock_try[i] / dev_bsize;
    665 			if (bread(fsreadfd, (char *)sblk.b_un.b_fs,
    666 			    super, (long)SBLOCKSIZE) != 0)
    667 				continue;
    668 			fs = sblk.b_un.b_fs;
    669 			if (detect_byteorder(fs, sblock_try[i]) == 0)
    670 				break;
    671 		}
    672 		if (sblock_try[i] == -1) {
    673 			badsb(listerr, "CAN'T FIND SUPERBLOCK");
    674 			return (0);
    675 		}
    676 	}
    677 	if (doswap) {
    678 		if (preen)
    679 			errx(EEXIT, "incompatible options -B and -p");
    680 		if (nflag)
    681 			errx(EEXIT, "incompatible options -B and -n");
    682 		if (endian == LITTLE_ENDIAN) {
    683 			if (!reply("CONVERT TO LITTLE ENDIAN"))
    684 				return 0;
    685 		} else if (endian == BIG_ENDIAN) {
    686 			if (!reply("CONVERT TO BIG ENDIAN"))
    687 				return 0;
    688 		} else
    689 			pfatal("INTERNAL ERROR: unknown endian");
    690 	}
    691 	if (needswap)
    692 		pwarn("** Swapped byte order\n");
    693 	/* swap SB byte order if asked */
    694 	if (doswap)
    695 		ffs_sb_swap(sblk.b_un.b_fs, sblk.b_un.b_fs);
    696 
    697 	memmove(sblock, sblk.b_un.b_fs, SBLOCKSIZE);
    698 	if (needswap)
    699 		ffs_sb_swap(sblk.b_un.b_fs, sblock);
    700 
    701 	is_ufs2 = sblock->fs_magic == FS_UFS2_MAGIC;
    702 
    703 	/*
    704 	 * run a few consistency checks of the super block
    705 	 */
    706 	if (sblock->fs_sbsize > SBLOCKSIZE)
    707 		{ badsb(listerr, "SIZE PREPOSTEROUSLY LARGE"); return (0); }
    708 	/*
    709 	 * Compute block size that the filesystem is based on,
    710 	 * according to fsbtodb, and adjust superblock block number
    711 	 * so we can tell if this is an alternate later.
    712 	 */
    713 	super *= dev_bsize;
    714 	dev_bsize = sblock->fs_fsize / fsbtodb(sblock, 1);
    715 	sblk.b_bno = super / dev_bsize;
    716 	sblk.b_size = SBLOCKSIZE;
    717 	if (bflag)
    718 		goto out;
    719 	/*
    720 	 * Set all possible fields that could differ, then do check
    721 	 * of whole super block against an alternate super block->
    722 	 * When an alternate super-block is specified this check is skipped.
    723 	 */
    724 	getblk(&asblk, cgsblock(sblock, sblock->fs_ncg - 1), sblock->fs_sbsize);
    725 	if (asblk.b_errs)
    726 		return (0);
    727 	/* swap SB byte order if asked */
    728 	if (doswap)
    729 		ffs_sb_swap(asblk.b_un.b_fs, asblk.b_un.b_fs);
    730 
    731 	memmove(altsblock, asblk.b_un.b_fs, sblock->fs_sbsize);
    732 	if (needswap)
    733 		ffs_sb_swap(asblk.b_un.b_fs, altsblock);
    734 	if (cmpsblks(sblock, altsblock)) {
    735 		if (debug) {
    736 			uint32_t *nlp, *olp, *endlp;
    737 
    738 			printf("superblock mismatches\n");
    739 			nlp = (uint32_t *)altsblock;
    740 			olp = (uint32_t *)sblock;
    741 			endlp = olp + (sblock->fs_sbsize / sizeof *olp);
    742 			for ( ; olp < endlp; olp++, nlp++) {
    743 				if (*olp == *nlp)
    744 					continue;
    745 				printf("offset %#x, original 0x%08x, alternate "
    746 				       "0x%08x\n",
    747 				    (int)((uint8_t *)olp-(uint8_t *)sblock),
    748 				    *olp, *nlp);
    749 			}
    750 		}
    751 		badsb(listerr,
    752 		"VALUES IN SUPER BLOCK DISAGREE WITH THOSE IN FIRST ALTERNATE");
    753 		return (0);
    754 	}
    755 out:
    756 
    757 	sb_oldfscompat_read(sblock, &sblocksave);
    758 
    759 	/* Now we know the SB is valid, we can write it back if needed */
    760 	if (doswap) {
    761 		sbdirty();
    762 		dirty(&asblk);
    763 	}
    764 	havesb = 1;
    765 	return (1);
    766 }
    767 
    768 int
    769 cmpsblks(const struct fs *sb, struct fs *asb)
    770 {
    771 	if (!is_ufs2 && ((sb->fs_old_flags & FS_FLAGS_UPDATED) == 0)) {
    772 		if (sb->fs_old_postblformat < FS_DYNAMICPOSTBLFMT)
    773 			return cmpsblks42(sb, asb);
    774 		else
    775 			return cmpsblks44(sb, asb);
    776 	}
    777 	if (asb->fs_sblkno != sb->fs_sblkno ||
    778 	    asb->fs_cblkno != sb->fs_cblkno ||
    779 	    asb->fs_iblkno != sb->fs_iblkno ||
    780 	    asb->fs_dblkno != sb->fs_dblkno ||
    781 	    asb->fs_ncg != sb->fs_ncg ||
    782 	    asb->fs_bsize != sb->fs_bsize ||
    783 	    asb->fs_fsize != sb->fs_fsize ||
    784 	    asb->fs_frag != sb->fs_frag ||
    785 	    asb->fs_bmask != sb->fs_bmask ||
    786 	    asb->fs_fmask != sb->fs_fmask ||
    787 	    asb->fs_bshift != sb->fs_bshift ||
    788 	    asb->fs_fshift != sb->fs_fshift ||
    789 	    asb->fs_fragshift != sb->fs_fragshift ||
    790 	    asb->fs_fsbtodb != sb->fs_fsbtodb ||
    791 	    asb->fs_sbsize != sb->fs_sbsize ||
    792 	    asb->fs_nindir != sb->fs_nindir ||
    793 	    asb->fs_inopb != sb->fs_inopb ||
    794 	    asb->fs_cssize != sb->fs_cssize ||
    795 	    asb->fs_ipg != sb->fs_ipg ||
    796 	    asb->fs_fpg != sb->fs_fpg ||
    797 	    asb->fs_magic != sb->fs_magic)
    798 		return 1;
    799 	return 0;
    800 }
    801 
    802 /* BSD 4.2 performed the following superblock comparison
    803  * It should correspond to FS_42POSTBLFMT
    804  * (although note that in 4.2, the fs_old_postblformat
    805  * field didn't exist and the corresponding bits are
    806  * located near the end of the postbl itself, where they
    807  * are not likely to be used.)
    808  */
    809 int
    810 cmpsblks42(const struct fs *sb, struct fs *asb)
    811 {
    812 	asb->fs_firstfield = sb->fs_firstfield; /* fs_link */
    813 	asb->fs_unused_1 = sb->fs_unused_1; /* fs_rlink */
    814 	asb->fs_old_time = sb->fs_old_time; /* fs_time */
    815 	asb->fs_old_cstotal = sb->fs_old_cstotal; /* fs_cstotal */
    816 	asb->fs_cgrotor = sb->fs_cgrotor;
    817 	asb->fs_fmod = sb->fs_fmod;
    818 	asb->fs_clean = sb->fs_clean;
    819 	asb->fs_ronly = sb->fs_ronly;
    820 	asb->fs_old_flags = sb->fs_old_flags;
    821 	asb->fs_maxcontig = sb->fs_maxcontig;
    822 	asb->fs_minfree = sb->fs_minfree;
    823 	asb->fs_old_rotdelay = sb->fs_old_rotdelay;
    824 	asb->fs_maxbpg = sb->fs_maxbpg;
    825 
    826 	/* The former fs_csp, totaling 128 bytes  */
    827 	memmove(asb->fs_ocsp, sb->fs_ocsp, sizeof sb->fs_ocsp);
    828 	asb->fs_contigdirs = sb->fs_contigdirs;
    829 	asb->fs_csp = sb->fs_csp;
    830 	asb->fs_maxcluster = sb->fs_maxcluster;
    831 	asb->fs_active = sb->fs_active;
    832 
    833 	/* The former fs_fsmnt, totaling 512 bytes */
    834 	memmove(asb->fs_fsmnt, sb->fs_fsmnt, sizeof sb->fs_fsmnt);
    835 	memmove(asb->fs_volname, sb->fs_volname, sizeof sb->fs_volname);
    836 
    837 	return memcmp(sb, asb, sb->fs_sbsize);
    838 }
    839 
    840 /* BSD 4.4 performed the following superblock comparison
    841  * This was used in NetBSD through 1.6.1
    842  *
    843  * Note that this implementation is destructive to asb.
    844  */
    845 int
    846 cmpsblks44(const struct fs *sb, struct fs *asb)
    847 {
    848 	/*
    849 	 * "Copy fields which we don't care if they're different in the
    850 	 * alternate superblocks, as they're either likely to be
    851 	 * different because they're per-cylinder-group specific, or
    852 	 * because they're transient details which are only maintained
    853 	 * in the primary superblock."
    854 	 */
    855 	asb->fs_firstfield = sb->fs_firstfield;
    856 	asb->fs_unused_1 = sb->fs_unused_1;
    857 	asb->fs_old_time = sb->fs_old_time;
    858 	asb->fs_old_cstotal = sb->fs_old_cstotal;
    859 	asb->fs_cgrotor = sb->fs_cgrotor;
    860 	asb->fs_fmod = sb->fs_fmod;
    861 	asb->fs_clean = sb->fs_clean;
    862 	asb->fs_ronly = sb->fs_ronly;
    863 	asb->fs_old_flags = sb->fs_old_flags;
    864 	asb->fs_maxcontig = sb->fs_maxcontig;
    865 	asb->fs_minfree = sb->fs_minfree;
    866 	asb->fs_optim = sb->fs_optim;
    867 	asb->fs_old_rotdelay = sb->fs_old_rotdelay;
    868 	asb->fs_maxbpg = sb->fs_maxbpg;
    869 
    870 	/* The former fs_csp and fs_maxcluster, totaling 128 bytes */
    871 	memmove(asb->fs_ocsp, sb->fs_ocsp, sizeof sb->fs_ocsp);
    872 	asb->fs_contigdirs = sb->fs_contigdirs;
    873 	asb->fs_csp = sb->fs_csp;
    874 	asb->fs_maxcluster = sb->fs_maxcluster;
    875 	asb->fs_active = sb->fs_active;
    876 
    877 	/* The former fs_fsmnt, totaling 512 bytes */
    878 	memmove(asb->fs_fsmnt, sb->fs_fsmnt, sizeof sb->fs_fsmnt);
    879 	memmove(asb->fs_volname, sb->fs_volname, sizeof sb->fs_volname);
    880 
    881 	/* The former fs_sparecon, totaling 200 bytes */
    882 	memmove(asb->fs_snapinum,
    883 		sb->fs_snapinum, sizeof sb->fs_snapinum);
    884 	asb->fs_avgfilesize = sb->fs_avgfilesize;
    885 	asb->fs_avgfpdir = sb->fs_avgfpdir;
    886 	asb->fs_save_cgsize = sb->fs_save_cgsize;
    887 	memmove(asb->fs_sparecon32,
    888 		sb->fs_sparecon32, sizeof sb->fs_sparecon32);
    889 	asb->fs_flags = sb->fs_flags;
    890 
    891 	/* Original comment:
    892 	 * "The following should not have to be copied, but need to be."
    893 	 */
    894 	asb->fs_fsbtodb = sb->fs_fsbtodb;
    895 	asb->fs_old_interleave = sb->fs_old_interleave;
    896 	asb->fs_old_npsect = sb->fs_old_npsect;
    897 	asb->fs_old_nrpos = sb->fs_old_nrpos;
    898 	asb->fs_state = sb->fs_state;
    899 	asb->fs_qbmask = sb->fs_qbmask;
    900 	asb->fs_qfmask = sb->fs_qfmask;
    901 	asb->fs_state = sb->fs_state;
    902 	asb->fs_maxfilesize = sb->fs_maxfilesize;
    903 
    904 	/*
    905 	 * "Compare the superblocks, effectively checking every other
    906 	 * field to see if they differ."
    907 	 */
    908 	return memcmp(sb, asb, sb->fs_sbsize);
    909 }
    910 
    911 
    912 static void
    913 badsb(int listerr, const char *s)
    914 {
    915 
    916 	if (!listerr)
    917 		return;
    918 	if (preen)
    919 		printf("%s: ", cdevname());
    920 	pfatal("BAD SUPER BLOCK: %s\n", s);
    921 }
    922 
    923 /*
    924  * Calculate a prototype superblock based on information in the disk label.
    925  * When done the cgsblock macro can be calculated and the fs_ncg field
    926  * can be used. Do NOT attempt to use other macros without verifying that
    927  * their needed information is available!
    928  */
    929 static int
    930 calcsb(const char *dev, int devfd, struct fs *fs)
    931 {
    932 	struct disklabel *lp;
    933 	struct partition *pp;
    934 	int i, nspf;
    935 
    936 	lp = getdisklabel(dev, devfd);
    937 	pp = getdisklabelpart(dev,lp);
    938 	if (pp == 0) {
    939 		pfatal("%s: CANNOT FIGURE OUT FILE SYSTEM PARTITION\n", dev);
    940 		return (0);
    941 	}
    942 	if ((pp->p_fstype != FS_BSDFFS) && (pp->p_fstype != FS_APPLEUFS)) {
    943 		pfatal("%s: NOT LABELED AS A BSD FILE SYSTEM (%s)\n",
    944 			dev, pp->p_fstype < FSMAXTYPES ?
    945 			fstypenames[pp->p_fstype] : "unknown");
    946 		return (0);
    947 	}
    948 	/* avoid divide by 0 */
    949 	if (pp->p_fsize == 0 || pp->p_frag == 0 || pp->p_cpg == 0) {
    950 		pfatal("%s: LABEL DOES NOT CONTAIN FILE SYSTEM PARAMETERS\n", dev);
    951 		return (0);
    952 	}
    953 	memset(fs, 0, sizeof(struct fs));
    954 	fs->fs_fsize = pp->p_fsize;
    955 	fs->fs_frag = pp->p_frag;
    956 	fs->fs_size = pp->p_size;
    957 	fs->fs_sblkno = roundup(
    958 		howmany(lp->d_bbsize + lp->d_sbsize, fs->fs_fsize),
    959 		fs->fs_frag);
    960 	nspf = fs->fs_fsize / lp->d_secsize;
    961 	fs->fs_old_nspf = nspf;
    962 	for (fs->fs_fsbtodb = 0, i = nspf; i > 1; i >>= 1)
    963 		fs->fs_fsbtodb++;
    964 	dev_bsize = lp->d_secsize;
    965 	if (fs->fs_magic == FS_UFS2_MAGIC) {
    966 		fs->fs_fpg = pp->p_cpg;
    967 		fs->fs_ncg = howmany(fs->fs_size, fs->fs_fpg);
    968 	} else /* if (fs->fs_magic == FS_UFS1_MAGIC) */ {
    969 		fs->fs_old_cpg = pp->p_cpg;
    970 		fs->fs_old_cgmask = 0xffffffff;
    971 		for (i = lp->d_ntracks; i > 1; i >>= 1)
    972 			fs->fs_old_cgmask <<= 1;
    973 		if (!POWEROF2(lp->d_ntracks))
    974 			fs->fs_old_cgmask <<= 1;
    975 		fs->fs_old_cgoffset = roundup(
    976 			howmany(lp->d_nsectors, nspf), fs->fs_frag);
    977 		fs->fs_fpg = (fs->fs_old_cpg * lp->d_secpercyl) / nspf;
    978 		fs->fs_ncg = howmany(fs->fs_size / lp->d_secpercyl,
    979 		    fs->fs_old_cpg);
    980 	}
    981 	return (1);
    982 }
    983 
    984 static struct disklabel *
    985 getdisklabel(const char *s, int fd)
    986 {
    987 	static struct disklabel lab;
    988 
    989 	if (ioctl(fd, DIOCGDINFO, (char *)&lab) < 0) {
    990 		if (s == NULL)
    991 			return ((struct disklabel *)NULL);
    992 		pwarn("ioctl (GCINFO): %s\n", strerror(errno));
    993 		errx(EEXIT, "%s: can't read disk label", s);
    994 	}
    995 	return (&lab);
    996 }
    997 
    998 static struct partition *
    999 getdisklabelpart(const char *dev, struct disklabel *lp)
   1000 {
   1001 	char *cp;
   1002 	int c;
   1003 
   1004 	cp = strchr(dev, '\0');
   1005 	if (cp == dev)
   1006 		return NULL;
   1007 
   1008 	c = (unsigned char)cp[-1];
   1009 	if (isdigit(c))
   1010 		/* eg "wd0", return info for first partition */
   1011 		return &lp->d_partitions[0];
   1012 
   1013 	if (c >= 'a' && c <= 'p')
   1014 		/* eg "wd0f", return info for specified partition */
   1015 		return &lp->d_partitions[c - 'a'];
   1016 	return NULL;
   1017 }
   1018 
   1019