1/*
2 * Copyright (c) 1980, 1986, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if 0
31#ifndef lint
32static const char sccsid[] = "@(#)setup.c	8.10 (Berkeley) 5/9/95";
33#endif /* not lint */
34#endif
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD: stable/10/sbin/fsck_ffs/setup.c 322860 2017-08-24 21:44:23Z mckusick $");
37
38#include <sys/param.h>
39#include <sys/stat.h>
40#define FSTYPENAMES
41#include <sys/disklabel.h>
42#include <sys/file.h>
43#include <sys/sysctl.h>
44
45#include <ufs/ufs/dinode.h>
46#include <ufs/ffs/fs.h>
47
48#include <ctype.h>
49#include <err.h>
50#include <errno.h>
51#include <limits.h>
52#include <stdint.h>
53#include <string.h>
54
55#include "fsck.h"
56
57struct bufarea asblk;
58#define altsblock (*asblk.b_un.b_fs)
59#define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
60
61static int calcsb(char *dev, int devfd, struct fs *fs);
62static void saverecovery(int readfd, int writefd);
63static int chkrecovery(int devfd);
64
65/*
66 * Read in a superblock finding an alternate if necessary.
67 * Return 1 if successful, 0 if unsuccessful, -1 if file system
68 * is already clean (ckclean and preen mode only).
69 */
70int
71setup(char *dev)
72{
73	long cg, asked, i, j;
74	long bmapsize;
75	struct stat statb;
76	struct fs proto;
77	size_t size;
78
79	havesb = 0;
80	fswritefd = -1;
81	cursnapshot = 0;
82	if (stat(dev, &statb) < 0) {
83		printf("Can't stat %s: %s\n", dev, strerror(errno));
84		if (bkgrdflag) {
85			unlink(snapname);
86			bkgrdflag = 0;
87		}
88		return (0);
89	}
90	if ((statb.st_mode & S_IFMT) != S_IFCHR &&
91	    (statb.st_mode & S_IFMT) != S_IFBLK) {
92		if (bkgrdflag != 0 && (statb.st_flags & SF_SNAPSHOT) == 0) {
93			unlink(snapname);
94			printf("background fsck lacks a snapshot\n");
95			exit(EEXIT);
96		}
97		if ((statb.st_flags & SF_SNAPSHOT) != 0 && cvtlevel == 0) {
98			cursnapshot = statb.st_ino;
99		} else {
100			if (cvtlevel == 0 ||
101			    (statb.st_flags & SF_SNAPSHOT) == 0) {
102				if (preen && bkgrdflag) {
103					unlink(snapname);
104					bkgrdflag = 0;
105				}
106				pfatal("%s is not a disk device", dev);
107				if (reply("CONTINUE") == 0) {
108					if (bkgrdflag) {
109						unlink(snapname);
110						bkgrdflag = 0;
111					}
112					return (0);
113				}
114			} else {
115				if (bkgrdflag) {
116					unlink(snapname);
117					bkgrdflag = 0;
118				}
119				pfatal("cannot convert a snapshot");
120				exit(EEXIT);
121			}
122		}
123	}
124	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
125		if (bkgrdflag) {
126			unlink(snapname);
127			bkgrdflag = 0;
128		}
129		printf("Can't open %s: %s\n", dev, strerror(errno));
130		return (0);
131	}
132	if (bkgrdflag) {
133		unlink(snapname);
134		size = MIBSIZE;
135		if (sysctlnametomib("vfs.ffs.adjrefcnt", adjrefcnt, &size) < 0||
136		    sysctlnametomib("vfs.ffs.adjblkcnt", adjblkcnt, &size) < 0||
137		    sysctlnametomib("vfs.ffs.freefiles", freefiles, &size) < 0||
138		    sysctlnametomib("vfs.ffs.freedirs", freedirs, &size) < 0 ||
139		    sysctlnametomib("vfs.ffs.freeblks", freeblks, &size) < 0) {
140			pfatal("kernel lacks background fsck support\n");
141			exit(EEXIT);
142		}
143		/*
144		 * When kernel is lack of runtime bgfsck superblock summary
145		 * adjustment functionality, it does not mean we can not
146		 * continue, as old kernels will recompute the summary at
147		 * mount time.  However, it will be an unexpected softupdates
148		 * inconsistency if it turns out that the summary is still
149		 * incorrect.  Set a flag so subsequent operation can know
150		 * this.
151		 */
152		bkgrdsumadj = 1;
153		if (sysctlnametomib("vfs.ffs.adjndir", adjndir, &size) < 0 ||
154		    sysctlnametomib("vfs.ffs.adjnbfree", adjnbfree, &size) < 0 ||
155		    sysctlnametomib("vfs.ffs.adjnifree", adjnifree, &size) < 0 ||
156		    sysctlnametomib("vfs.ffs.adjnffree", adjnffree, &size) < 0 ||
157		    sysctlnametomib("vfs.ffs.adjnumclusters", adjnumclusters, &size) < 0) {
158			bkgrdsumadj = 0;
159			pwarn("kernel lacks runtime superblock summary adjustment support");
160		}
161		cmd.version = FFS_CMD_VERSION;
162		cmd.handle = fsreadfd;
163		fswritefd = -1;
164	}
165	if (preen == 0)
166		printf("** %s", dev);
167	if (bkgrdflag == 0 &&
168	    (nflag || (fswritefd = open(dev, O_WRONLY)) < 0)) {
169		fswritefd = -1;
170		if (preen)
171			pfatal("NO WRITE ACCESS");
172		printf(" (NO WRITE)");
173	}
174	if (preen == 0)
175		printf("\n");
176	/*
177	 * Read in the superblock, looking for alternates if necessary
178	 */
179	if (readsb(1) == 0) {
180		skipclean = 0;
181		if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0)
182			return(0);
183		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
184			return (0);
185		for (cg = 0; cg < proto.fs_ncg; cg++) {
186			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
187			if (readsb(0) != 0)
188				break;
189		}
190		if (cg >= proto.fs_ncg) {
191			printf("%s %s\n%s %s\n%s %s\n",
192				"SEARCH FOR ALTERNATE SUPER-BLOCK",
193				"FAILED. YOU MUST USE THE",
194				"-b OPTION TO FSCK TO SPECIFY THE",
195				"LOCATION OF AN ALTERNATE",
196				"SUPER-BLOCK TO SUPPLY NEEDED",
197				"INFORMATION; SEE fsck_ffs(8).");
198			bflag = 0;
199			return(0);
200		}
201		pwarn("USING ALTERNATE SUPERBLOCK AT %jd\n", bflag);
202		bflag = 0;
203	}
204	if (skipclean && ckclean && sblock.fs_clean) {
205		pwarn("FILE SYSTEM CLEAN; SKIPPING CHECKS\n");
206		return (-1);
207	}
208	maxfsblock = sblock.fs_size;
209	maxino = sblock.fs_ncg * sblock.fs_ipg;
210	/*
211	 * Check and potentially fix certain fields in the super block.
212	 */
213	if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
214		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
215		if (reply("SET TO DEFAULT") == 1) {
216			sblock.fs_optim = FS_OPTTIME;
217			sbdirty();
218		}
219	}
220	if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
221		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
222			sblock.fs_minfree);
223		if (reply("SET TO DEFAULT") == 1) {
224			sblock.fs_minfree = 10;
225			sbdirty();
226		}
227	}
228	if (sblock.fs_magic == FS_UFS1_MAGIC &&
229	    sblock.fs_old_inodefmt < FS_44INODEFMT) {
230		pwarn("Format of file system is too old.\n");
231		pwarn("Must update to modern format using a version of fsck\n");
232		pfatal("from before 2002 with the command ``fsck -c 2''\n");
233		exit(EEXIT);
234	}
235	if (asblk.b_dirty && !bflag) {
236		memmove(&altsblock, &sblock, (size_t)sblock.fs_sbsize);
237		flush(fswritefd, &asblk);
238	}
239	if (preen == 0 && yflag == 0 && sblock.fs_magic == FS_UFS2_MAGIC &&
240	    fswritefd != -1 && chkrecovery(fsreadfd) == 0 &&
241	    reply("SAVE DATA TO FIND ALTERNATE SUPERBLOCKS") != 0)
242		saverecovery(fsreadfd, fswritefd);
243	/*
244	 * read in the summary info.
245	 */
246	asked = 0;
247	sblock.fs_csp = Calloc(1, sblock.fs_cssize);
248	if (sblock.fs_csp == NULL) {
249		printf("cannot alloc %u bytes for cg summary info\n",
250		    (unsigned)sblock.fs_cssize);
251		goto badsb;
252	}
253	for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
254		size = sblock.fs_cssize - i < sblock.fs_bsize ?
255		    sblock.fs_cssize - i : sblock.fs_bsize;
256		readcnt[sblk.b_type]++;
257		if (blread(fsreadfd, (char *)sblock.fs_csp + i,
258		    fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
259		    size) != 0 && !asked) {
260			pfatal("BAD SUMMARY INFORMATION");
261			if (reply("CONTINUE") == 0) {
262				ckfini(0);
263				exit(EEXIT);
264			}
265			asked++;
266		}
267	}
268	/*
269	 * allocate and initialize the necessary maps
270	 */
271	bmapsize = roundup(howmany(maxfsblock, CHAR_BIT), sizeof(short));
272	blockmap = Calloc((unsigned)bmapsize, sizeof (char));
273	if (blockmap == NULL) {
274		printf("cannot alloc %u bytes for blockmap\n",
275		    (unsigned)bmapsize);
276		goto badsb;
277	}
278	inostathead = Calloc((unsigned)(sblock.fs_ncg),
279	    sizeof(struct inostatlist));
280	if (inostathead == NULL) {
281		printf("cannot alloc %u bytes for inostathead\n",
282		    (unsigned)(sizeof(struct inostatlist) * (sblock.fs_ncg)));
283		goto badsb;
284	}
285	numdirs = MAX(sblock.fs_cstotal.cs_ndir, 128);
286	dirhash = numdirs;
287	inplast = 0;
288	listmax = numdirs + 10;
289	inpsort = (struct inoinfo **)Calloc((unsigned)listmax,
290	    sizeof(struct inoinfo *));
291	inphead = (struct inoinfo **)Calloc((unsigned)numdirs,
292	    sizeof(struct inoinfo *));
293	if (inpsort == NULL || inphead == NULL) {
294		printf("cannot alloc %ju bytes for inphead\n",
295		    (uintmax_t)numdirs * sizeof(struct inoinfo *));
296		goto badsb;
297	}
298	bufinit();
299	if (sblock.fs_flags & FS_DOSOFTDEP)
300		usedsoftdep = 1;
301	else
302		usedsoftdep = 0;
303	return (1);
304
305badsb:
306	ckfini(0);
307	return (0);
308}
309
310/*
311 * Possible superblock locations ordered from most to least likely.
312 */
313static int sblock_try[] = SBLOCKSEARCH;
314
315#define BAD_MAGIC_MSG \
316"The previous newfs operation on this volume did not complete.\n" \
317"You must complete newfs before mounting this volume.\n"
318
319/*
320 * Read in the super block and its summary info.
321 */
322int
323readsb(int listerr)
324{
325	ufs2_daddr_t super;
326	int i, bad;
327
328	if (bflag) {
329		super = bflag;
330		readcnt[sblk.b_type]++;
331		if ((blread(fsreadfd, (char *)&sblock, super, (long)SBLOCKSIZE)))
332			return (0);
333		if (sblock.fs_magic == FS_BAD_MAGIC) {
334			fprintf(stderr, BAD_MAGIC_MSG);
335			exit(11);
336		}
337		if (sblock.fs_magic != FS_UFS1_MAGIC &&
338		    sblock.fs_magic != FS_UFS2_MAGIC) {
339			fprintf(stderr, "%jd is not a file system superblock\n",
340			    bflag);
341			return (0);
342		}
343	} else {
344		for (i = 0; sblock_try[i] != -1; i++) {
345			super = sblock_try[i] / dev_bsize;
346			readcnt[sblk.b_type]++;
347			if ((blread(fsreadfd, (char *)&sblock, super,
348			    (long)SBLOCKSIZE)))
349				return (0);
350			if (sblock.fs_magic == FS_BAD_MAGIC) {
351				fprintf(stderr, BAD_MAGIC_MSG);
352				exit(11);
353			}
354			if ((sblock.fs_magic == FS_UFS1_MAGIC ||
355			     (sblock.fs_magic == FS_UFS2_MAGIC &&
356			      sblock.fs_sblockloc == sblock_try[i])) &&
357			    sblock.fs_ncg >= 1 &&
358			    sblock.fs_bsize >= MINBSIZE &&
359			    sblock.fs_sbsize >= roundup(sizeof(struct fs), dev_bsize))
360				break;
361		}
362		if (sblock_try[i] == -1) {
363			fprintf(stderr, "Cannot find file system superblock\n");
364			return (0);
365		}
366	}
367	/*
368	 * Compute block size that the file system is based on,
369	 * according to fsbtodb, and adjust superblock block number
370	 * so we can tell if this is an alternate later.
371	 */
372	super *= dev_bsize;
373	dev_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
374	sblk.b_bno = super / dev_bsize;
375	sblk.b_size = SBLOCKSIZE;
376	/*
377	 * Compare all fields that should not differ in alternate super block.
378	 * When an alternate super-block is specified this check is skipped.
379	 */
380	if (bflag)
381		goto out;
382	getblk(&asblk, cgsblock(&sblock, sblock.fs_ncg - 1), sblock.fs_sbsize);
383	if (asblk.b_errs)
384		return (0);
385	bad = 0;
386#define CHK(x, y)				\
387	if (altsblock.x != sblock.x) {		\
388		bad++;				\
389		if (listerr && debug)		\
390			printf("SUPER BLOCK VS ALTERNATE MISMATCH %s: " y " vs " y "\n", \
391			    #x, (intmax_t)sblock.x, (intmax_t)altsblock.x); \
392	}
393	CHK(fs_sblkno, "%jd");
394	CHK(fs_cblkno, "%jd");
395	CHK(fs_iblkno, "%jd");
396	CHK(fs_dblkno, "%jd");
397	CHK(fs_ncg, "%jd");
398	CHK(fs_bsize, "%jd");
399	CHK(fs_fsize, "%jd");
400	CHK(fs_frag, "%jd");
401	CHK(fs_bmask, "%#jx");
402	CHK(fs_fmask, "%#jx");
403	CHK(fs_bshift, "%jd");
404	CHK(fs_fshift, "%jd");
405	CHK(fs_fragshift, "%jd");
406	CHK(fs_fsbtodb, "%jd");
407	CHK(fs_sbsize, "%jd");
408	CHK(fs_nindir, "%jd");
409	CHK(fs_inopb, "%jd");
410	CHK(fs_cssize, "%jd");
411	CHK(fs_ipg, "%jd");
412	CHK(fs_fpg, "%jd");
413	CHK(fs_magic, "%#jx");
414#undef CHK
415	if (bad) {
416		if (listerr == 0)
417			return (0);
418		if (preen)
419			printf("%s: ", cdevname);
420		printf(
421		    "VALUES IN SUPER BLOCK LSB=%jd DISAGREE WITH THOSE IN\n"
422		    "LAST ALTERNATE LSB=%jd\n",
423		    sblk.b_bno, asblk.b_bno);
424		if (reply("IGNORE ALTERNATE SUPER BLOCK") == 0)
425			return (0);
426	}
427out:
428	/*
429	 * If not yet done, update UFS1 superblock with new wider fields.
430	 */
431	if (sblock.fs_magic == FS_UFS1_MAGIC &&
432	    sblock.fs_maxbsize != sblock.fs_bsize) {
433		sblock.fs_maxbsize = sblock.fs_bsize;
434		sblock.fs_time = sblock.fs_old_time;
435		sblock.fs_size = sblock.fs_old_size;
436		sblock.fs_dsize = sblock.fs_old_dsize;
437		sblock.fs_csaddr = sblock.fs_old_csaddr;
438		sblock.fs_cstotal.cs_ndir = sblock.fs_old_cstotal.cs_ndir;
439		sblock.fs_cstotal.cs_nbfree = sblock.fs_old_cstotal.cs_nbfree;
440		sblock.fs_cstotal.cs_nifree = sblock.fs_old_cstotal.cs_nifree;
441		sblock.fs_cstotal.cs_nffree = sblock.fs_old_cstotal.cs_nffree;
442	}
443	havesb = 1;
444	return (1);
445}
446
447void
448sblock_init(void)
449{
450
451	fswritefd = -1;
452	fsmodified = 0;
453	lfdir = 0;
454	initbarea(&sblk, BT_SUPERBLK);
455	initbarea(&asblk, BT_SUPERBLK);
456	sblk.b_un.b_buf = Malloc(SBLOCKSIZE);
457	asblk.b_un.b_buf = Malloc(SBLOCKSIZE);
458	if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL)
459		errx(EEXIT, "cannot allocate space for superblock");
460	dev_bsize = secsize = DEV_BSIZE;
461}
462
463/*
464 * Calculate a prototype superblock based on information in the boot area.
465 * When done the cgsblock macro can be calculated and the fs_ncg field
466 * can be used. Do NOT attempt to use other macros without verifying that
467 * their needed information is available!
468 */
469static int
470calcsb(char *dev, int devfd, struct fs *fs)
471{
472	struct fsrecovery fsr;
473
474	/*
475	 * We need fragments-per-group and the partition-size.
476	 *
477	 * Newfs stores these details at the end of the boot block area
478	 * at the start of the filesystem partition. If they have been
479	 * overwritten by a boot block, we fail. But usually they are
480	 * there and we can use them.
481	 */
482	if (blread(devfd, (char *)&fsr,
483	    (SBLOCK_UFS2 - sizeof(fsr)) / dev_bsize, sizeof(fsr)) ||
484	    fsr.fsr_magic != FS_UFS2_MAGIC)
485		return (0);
486	memset(fs, 0, sizeof(struct fs));
487	fs->fs_fpg = fsr.fsr_fpg;
488	fs->fs_fsbtodb = fsr.fsr_fsbtodb;
489	fs->fs_sblkno = fsr.fsr_sblkno;
490	fs->fs_magic = fsr.fsr_magic;
491	fs->fs_ncg = fsr.fsr_ncg;
492	return (1);
493}
494
495/*
496 * Check to see if recovery information exists.
497 */
498static int
499chkrecovery(int devfd)
500{
501	struct fsrecovery fsr;
502
503	if (blread(devfd, (char *)&fsr,
504	    (SBLOCK_UFS2 - sizeof(fsr)) / dev_bsize, sizeof(fsr)) ||
505	    fsr.fsr_magic != FS_UFS2_MAGIC)
506		return (0);
507	return (1);
508}
509
510/*
511 * Read the last sector of the boot block, replace the last
512 * 20 bytes with the recovery information, then write it back.
513 * The recovery information only works for UFS2 filesystems.
514 */
515static void
516saverecovery(int readfd, int writefd)
517{
518	struct fsrecovery fsr;
519
520	if (sblock.fs_magic != FS_UFS2_MAGIC ||
521	    blread(readfd, (char *)&fsr,
522	    (SBLOCK_UFS2 - sizeof(fsr)) / dev_bsize, sizeof(fsr)))
523		return;
524	fsr.fsr_magic = sblock.fs_magic;
525	fsr.fsr_fpg = sblock.fs_fpg;
526	fsr.fsr_fsbtodb = sblock.fs_fsbtodb;
527	fsr.fsr_sblkno = sblock.fs_sblkno;
528	fsr.fsr_ncg = sblock.fs_ncg;
529	blwrite(writefd, (char *)&fsr, (SBLOCK_UFS2 - sizeof(fsr)) / dev_bsize,
530	    sizeof(fsr));
531}
532