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/11/sbin/fsck_ffs/setup.c 359754 2020-04-09 20:38:36Z kevans $");
37
38#include <sys/param.h>
39#include <sys/disk.h>
40#include <sys/stat.h>
41#define FSTYPENAMES
42#include <sys/disklabel.h>
43#include <sys/file.h>
44#include <sys/sysctl.h>
45
46#include <ufs/ufs/dinode.h>
47#include <ufs/ffs/fs.h>
48
49#include <ctype.h>
50#include <err.h>
51#include <errno.h>
52#include <limits.h>
53#include <stdint.h>
54#include <string.h>
55
56#include "fsck.h"
57
58struct inoinfo **inphead, **inpsort;
59
60struct bufarea asblk;
61#define altsblock (*asblk.b_un.b_fs)
62#define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
63
64static int calcsb(char *dev, int devfd, struct fs *fs);
65static void saverecovery(int readfd, int writefd);
66static int chkrecovery(int devfd);
67
68/*
69 * Read in a superblock finding an alternate if necessary.
70 * Return 1 if successful, 0 if unsuccessful, -1 if file system
71 * is already clean (ckclean and preen mode only).
72 */
73int
74setup(char *dev)
75{
76	long cg, asked, i, j;
77	long bmapsize;
78	struct stat statb;
79	struct fs proto;
80	size_t size;
81
82	havesb = 0;
83	fswritefd = -1;
84	cursnapshot = 0;
85	if (stat(dev, &statb) < 0) {
86		printf("Can't stat %s: %s\n", dev, strerror(errno));
87		if (bkgrdflag) {
88			unlink(snapname);
89			bkgrdflag = 0;
90		}
91		return (0);
92	}
93	if ((statb.st_mode & S_IFMT) != S_IFCHR &&
94	    (statb.st_mode & S_IFMT) != S_IFBLK) {
95		if (bkgrdflag != 0 && (statb.st_flags & SF_SNAPSHOT) == 0) {
96			unlink(snapname);
97			printf("background fsck lacks a snapshot\n");
98			exit(EEXIT);
99		}
100		if ((statb.st_flags & SF_SNAPSHOT) != 0 && cvtlevel == 0) {
101			cursnapshot = statb.st_ino;
102		} else {
103			if (cvtlevel == 0 ||
104			    (statb.st_flags & SF_SNAPSHOT) == 0) {
105				if (preen && bkgrdflag) {
106					unlink(snapname);
107					bkgrdflag = 0;
108				}
109				pfatal("%s is not a disk device", dev);
110				if (reply("CONTINUE") == 0) {
111					if (bkgrdflag) {
112						unlink(snapname);
113						bkgrdflag = 0;
114					}
115					return (0);
116				}
117			} else {
118				if (bkgrdflag) {
119					unlink(snapname);
120					bkgrdflag = 0;
121				}
122				pfatal("cannot convert a snapshot");
123				exit(EEXIT);
124			}
125		}
126	}
127	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
128		if (bkgrdflag) {
129			unlink(snapname);
130			bkgrdflag = 0;
131		}
132		printf("Can't open %s: %s\n", dev, strerror(errno));
133		return (0);
134	}
135	if (bkgrdflag) {
136		unlink(snapname);
137		size = MIBSIZE;
138		if (sysctlnametomib("vfs.ffs.adjrefcnt", adjrefcnt, &size) < 0||
139		    sysctlnametomib("vfs.ffs.adjblkcnt", adjblkcnt, &size) < 0||
140		    sysctlnametomib("vfs.ffs.setsize", setsize, &size) < 0 ||
141		    sysctlnametomib("vfs.ffs.freefiles", freefiles, &size) < 0||
142		    sysctlnametomib("vfs.ffs.freedirs", freedirs, &size) < 0 ||
143		    sysctlnametomib("vfs.ffs.freeblks", freeblks, &size) < 0) {
144			pfatal("kernel lacks background fsck support\n");
145			exit(EEXIT);
146		}
147		/*
148		 * When kernel is lack of runtime bgfsck superblock summary
149		 * adjustment functionality, it does not mean we can not
150		 * continue, as old kernels will recompute the summary at
151		 * mount time.  However, it will be an unexpected softupdates
152		 * inconsistency if it turns out that the summary is still
153		 * incorrect.  Set a flag so subsequent operation can know
154		 * this.
155		 */
156		bkgrdsumadj = 1;
157		if (sysctlnametomib("vfs.ffs.adjndir", adjndir, &size) < 0 ||
158		    sysctlnametomib("vfs.ffs.adjnbfree", adjnbfree, &size) < 0 ||
159		    sysctlnametomib("vfs.ffs.adjnifree", adjnifree, &size) < 0 ||
160		    sysctlnametomib("vfs.ffs.adjnffree", adjnffree, &size) < 0 ||
161		    sysctlnametomib("vfs.ffs.adjnumclusters", adjnumclusters, &size) < 0) {
162			bkgrdsumadj = 0;
163			pwarn("kernel lacks runtime superblock summary adjustment support");
164		}
165		cmd.version = FFS_CMD_VERSION;
166		cmd.handle = fsreadfd;
167		fswritefd = -1;
168	}
169	if (preen == 0)
170		printf("** %s", dev);
171	if (bkgrdflag == 0 &&
172	    (nflag || (fswritefd = open(dev, O_WRONLY)) < 0)) {
173		fswritefd = -1;
174		if (preen)
175			pfatal("NO WRITE ACCESS");
176		printf(" (NO WRITE)");
177	}
178	if (preen == 0)
179		printf("\n");
180	/*
181	 * Read in the superblock, looking for alternates if necessary
182	 */
183	if (readsb(1) == 0) {
184		skipclean = 0;
185		if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0)
186			return(0);
187		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
188			return (0);
189		for (cg = 0; cg < proto.fs_ncg; cg++) {
190			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
191			if (readsb(0) != 0)
192				break;
193		}
194		if (cg >= proto.fs_ncg) {
195			printf("%s %s\n%s %s\n%s %s\n",
196				"SEARCH FOR ALTERNATE SUPER-BLOCK",
197				"FAILED. YOU MUST USE THE",
198				"-b OPTION TO FSCK TO SPECIFY THE",
199				"LOCATION OF AN ALTERNATE",
200				"SUPER-BLOCK TO SUPPLY NEEDED",
201				"INFORMATION; SEE fsck_ffs(8).");
202			bflag = 0;
203			return(0);
204		}
205		pwarn("USING ALTERNATE SUPERBLOCK AT %jd\n", bflag);
206		bflag = 0;
207	}
208	if (skipclean && ckclean && sblock.fs_clean) {
209		pwarn("FILE SYSTEM CLEAN; SKIPPING CHECKS\n");
210		return (-1);
211	}
212	maxfsblock = sblock.fs_size;
213	maxino = sblock.fs_ncg * sblock.fs_ipg;
214	/*
215	 * Check and potentially fix certain fields in the super block.
216	 */
217	if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
218		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
219		if (reply("SET TO DEFAULT") == 1) {
220			sblock.fs_optim = FS_OPTTIME;
221			sbdirty();
222		}
223	}
224	if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
225		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
226			sblock.fs_minfree);
227		if (reply("SET TO DEFAULT") == 1) {
228			sblock.fs_minfree = 10;
229			sbdirty();
230		}
231	}
232	if (sblock.fs_magic == FS_UFS1_MAGIC &&
233	    sblock.fs_old_inodefmt < FS_44INODEFMT) {
234		pwarn("Format of file system is too old.\n");
235		pwarn("Must update to modern format using a version of fsck\n");
236		pfatal("from before 2002 with the command ``fsck -c 2''\n");
237		exit(EEXIT);
238	}
239	if (asblk.b_dirty && !bflag) {
240		memmove(&altsblock, &sblock, (size_t)sblock.fs_sbsize);
241		flush(fswritefd, &asblk);
242	}
243	if (preen == 0 && yflag == 0 && sblock.fs_magic == FS_UFS2_MAGIC &&
244	    fswritefd != -1 && chkrecovery(fsreadfd) == 0 &&
245	    reply("SAVE DATA TO FIND ALTERNATE SUPERBLOCKS") != 0)
246		saverecovery(fsreadfd, fswritefd);
247	/*
248	 * read in the summary info.
249	 */
250	asked = 0;
251	sblock.fs_csp = Calloc(1, sblock.fs_cssize);
252	if (sblock.fs_csp == NULL) {
253		printf("cannot alloc %u bytes for cg summary info\n",
254		    (unsigned)sblock.fs_cssize);
255		goto badsb;
256	}
257	for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
258		size = MIN(sblock.fs_cssize - i, sblock.fs_bsize);
259		readcnt[sblk.b_type]++;
260		if (blread(fsreadfd, (char *)sblock.fs_csp + i,
261		    fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
262		    size) != 0 && !asked) {
263			pfatal("BAD SUMMARY INFORMATION");
264			if (reply("CONTINUE") == 0) {
265				ckfini(0);
266				exit(EEXIT);
267			}
268			asked++;
269		}
270	}
271	/*
272	 * allocate and initialize the necessary maps
273	 */
274	bmapsize = roundup(howmany(maxfsblock, CHAR_BIT), sizeof(short));
275	blockmap = Calloc((unsigned)bmapsize, sizeof (char));
276	if (blockmap == NULL) {
277		printf("cannot alloc %u bytes for blockmap\n",
278		    (unsigned)bmapsize);
279		goto badsb;
280	}
281	inostathead = Calloc(sblock.fs_ncg, sizeof(struct inostatlist));
282	if (inostathead == NULL) {
283		printf("cannot alloc %u bytes for inostathead\n",
284		    (unsigned)(sizeof(struct inostatlist) * (sblock.fs_ncg)));
285		goto badsb;
286	}
287	numdirs = MAX(sblock.fs_cstotal.cs_ndir, 128);
288	dirhash = numdirs;
289	inplast = 0;
290	listmax = numdirs + 10;
291	inpsort = (struct inoinfo **)Calloc(listmax, sizeof(struct inoinfo *));
292	inphead = (struct inoinfo **)Calloc(numdirs, 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	char *fsrbuf;
474	u_int secsize;
475
476	/*
477	 * We need fragments-per-group and the partition-size.
478	 *
479	 * Newfs stores these details at the end of the boot block area
480	 * at the start of the filesystem partition. If they have been
481	 * overwritten by a boot block, we fail. But usually they are
482	 * there and we can use them.
483	 */
484	if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1)
485		return (0);
486	fsrbuf = Malloc(secsize);
487	if (fsrbuf == NULL)
488		errx(EEXIT, "calcsb: cannot allocate recovery buffer");
489	if (blread(devfd, fsrbuf,
490	    (SBLOCK_UFS2 - secsize) / dev_bsize, secsize) != 0)
491		return (0);
492	fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
493	if (fsr->fsr_magic != FS_UFS2_MAGIC)
494		return (0);
495	memset(fs, 0, sizeof(struct fs));
496	fs->fs_fpg = fsr->fsr_fpg;
497	fs->fs_fsbtodb = fsr->fsr_fsbtodb;
498	fs->fs_sblkno = fsr->fsr_sblkno;
499	fs->fs_magic = fsr->fsr_magic;
500	fs->fs_ncg = fsr->fsr_ncg;
501	free(fsrbuf);
502	return (1);
503}
504
505/*
506 * Check to see if recovery information exists.
507 * Return 1 if it exists or cannot be created.
508 * Return 0 if it does not exist and can be created.
509 */
510static int
511chkrecovery(int devfd)
512{
513	struct fsrecovery *fsr;
514	char *fsrbuf;
515	u_int secsize;
516
517	/*
518	 * Could not determine if backup material exists, so do not
519	 * offer to create it.
520	 */
521	if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1 ||
522	    (fsrbuf = Malloc(secsize)) == NULL ||
523	    blread(devfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
524	      secsize) != 0)
525		return (1);
526	/*
527	 * Recovery material has already been created, so do not
528	 * need to create it again.
529	 */
530	fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
531	if (fsr->fsr_magic == FS_UFS2_MAGIC) {
532		free(fsrbuf);
533		return (1);
534	}
535	/*
536	 * Recovery material has not been created and can be if desired.
537	 */
538	free(fsrbuf);
539	return (0);
540}
541
542/*
543 * Read the last sector of the boot block, replace the last
544 * 20 bytes with the recovery information, then write it back.
545 * The recovery information only works for UFS2 filesystems.
546 */
547static void
548saverecovery(int readfd, int writefd)
549{
550	struct fsrecovery *fsr;
551	char *fsrbuf;
552	u_int secsize;
553
554	if (sblock.fs_magic != FS_UFS2_MAGIC ||
555	    ioctl(readfd, DIOCGSECTORSIZE, &secsize) == -1 ||
556	    (fsrbuf = Malloc(secsize)) == NULL ||
557	    blread(readfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
558	      secsize) != 0) {
559		printf("RECOVERY DATA COULD NOT BE CREATED\n");
560		return;
561	}
562	fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
563	fsr->fsr_magic = sblock.fs_magic;
564	fsr->fsr_fpg = sblock.fs_fpg;
565	fsr->fsr_fsbtodb = sblock.fs_fsbtodb;
566	fsr->fsr_sblkno = sblock.fs_sblkno;
567	fsr->fsr_ncg = sblock.fs_ncg;
568	blwrite(writefd, fsrbuf, (SBLOCK_UFS2 - secsize) / secsize, secsize);
569	free(fsrbuf);
570}
571