xref: /src/sbin/scan_ffs/scan_ffs.c

/* $NetBSD: scan_ffs.c,v 1.33 2022/01/19 01:40:05 mrg Exp $ */

/*
 * Copyright (c) 2005-2007 Juan Romero Pardines
 * Copyright (c) 1998 Niklas Hallqvist, Tobias Weingartner
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Currently it can detect FFS and LFS partitions (version 1 or 2)
 * up to 8192/65536 fragsize/blocksize.
 */

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: scan_ffs.c,v 1.33 2022/01/19 01:40:05 mrg Exp $");
#endif /* not lint */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/disklabel.h>
#include <sys/dkio.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#include <sys/mount.h>

#include <ufs/lfs/lfs.h>
#include <ufs/lfs/lfs_accessors.h>
#include <ufs/lfs/lfs_extern.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <err.h>
#include <util.h>

#define BLK_CNT		(blk + (n / 512))

/* common struct for FFS/LFS */
struct sblockinfo {
	struct lfs	*lfs;
	struct fs	*ffs;
	uint64_t	lfs_off;
	uint64_t	ffs_off;
	char		lfs_path[MAXMNTLEN];
	char		ffs_path[MAXMNTLEN];
};

static daddr_t	blk, lastblk;

static int	eflag = 0;
static int	fflag = 0;
static int	flags = 0;
static int	sbaddr = 0; /* counter for the LFS superblocks */

static char	device[MAXPATHLEN];
static const char *fstypes[] = { "NONE", "FFSv1", "FFSv2" };

static sig_atomic_t print_info = 0;

#define FSTYPE_NONE	0
#define FSTYPE_FFSV1	1
#define FSTYPE_FFSV2	2

#define SBCOUNT		128 /* may be changed */
#define SBPASS		(SBCOUNT * SBLOCKSIZE / 512)

/* This is only useful for LFS */

/* first sblock address contains the correct offset */
#define FIRST_SBLOCK_ADDRESS    1
/* second and third sblock address contain lfs_fsmnt[MAXMNTLEN] */
#define SECOND_SBLOCK_ADDRESS   2
/* last sblock address in a LFS partition */
#define MAX_SBLOCK_ADDRESS      10

enum { NADA=0, VERBOSE=1, LABELS=2, BLOCKS=4 };

/* FFS functions */
static void	ffs_printpart(struct sblockinfo *, int, size_t, int);
static void	ffs_scan(struct sblockinfo *, int);
static int	ffs_checkver(struct sblockinfo *);
/* LFS functions */
static void	lfs_printpart(struct sblockinfo *, int, int);
static void	lfs_scan(struct sblockinfo *, int);
/* common functions */
static void	usage(void) __dead;
static int	scan_disk(int, daddr_t, daddr_t, int);

static void
got_siginfo(int signo)
{

	print_info = 1;
}

static int
ffs_checkver(struct sblockinfo *sbi)
{
	switch (sbi->ffs->fs_magic) {
		case FS_UFS1_MAGIC:
		case FS_UFS1_MAGIC_SWAPPED:
			sbi->ffs->fs_size = sbi->ffs->fs_old_size;
			return FSTYPE_FFSV1;
		case FS_UFS2_MAGIC:
		case FS_UFS2_MAGIC_SWAPPED:
			return FSTYPE_FFSV2;
		default:
			return FSTYPE_NONE;
	}
}

static void
ffs_printpart(struct sblockinfo *sbi, int flag, size_t ffsize, int n)
{
	int offset, ver;

	switch (flag) {
	case VERBOSE:
		switch (ffs_checkver(sbi)) {
		case FSTYPE_FFSV1:
			(void)printf("offset: %" PRIu64 " n: %d "
			    "id: %x,%x size: %" PRIu64 "\n",
			    BLK_CNT - (2 * SBLOCKSIZE / 512), n,
			    sbi->ffs->fs_id[0], sbi->ffs->fs_id[1],
			    (uint64_t)sbi->ffs->fs_size *
			    sbi->ffs->fs_fsize / 512);
			break;
		case FSTYPE_FFSV2:
			(void)printf("offset: %" PRIu64 " n: %d "
			    "id: %x,%x size: %" PRIu64 "\n",
			    BLK_CNT - (ffsize * SBLOCKSIZE / 512+128),
			    n, sbi->ffs->fs_id[0], sbi->ffs->fs_id[1],
			    (uint64_t)sbi->ffs->fs_size *
			    sbi->ffs->fs_fsize / 512);
			break;
		default:
			break;
		}
		break;
	case LABELS:
		(void)printf("X:  %9" PRIu64,
			(uint64_t)(sbi->ffs->fs_size *
			sbi->ffs->fs_fsize / 512));
		switch (ffs_checkver(sbi)) {
		case FSTYPE_FFSV1:
			(void)printf(" %9" PRIu64,
			    BLK_CNT - (ffsize * SBLOCKSIZE / 512));
			break;
		case FSTYPE_FFSV2:
			(void)printf(" %9" PRIu64,
			    BLK_CNT - (ffsize * SBLOCKSIZE / 512 + 128));
			break;
		default:
			break;
		}
		(void)printf(" 4.2BSD %6d %5d %7d # %s [%s]\n",
			sbi->ffs->fs_fsize, sbi->ffs->fs_bsize,
			sbi->ffs->fs_old_cpg,
			sbi->ffs_path, fstypes[ffs_checkver(sbi)]);
		break;
	case BLOCKS:
	default:
		(void)printf("%s ", fstypes[ffs_checkver(sbi)]);
		ver = ffs_checkver(sbi);
		if (ver == FSTYPE_NONE)
			break;

		offset = 0;
		if (flag == BLOCKS)
			(void)printf("sb ");
		else if (ver == FSTYPE_FFSV1)
			offset = (2 * SBLOCKSIZE / 512);
		else if (ver == FSTYPE_FFSV2)
			offset = (ffsize * SBLOCKSIZE / 512 + 128);

		(void)printf("at %" PRIu64, BLK_CNT - offset);
		(void)printf(" size %" PRIu64 ", last mounted on %s\n",
			(uint64_t)(sbi->ffs->fs_size *
			sbi->ffs->fs_fsize / 512), sbi->ffs_path);
		break;
	}
}

static void
ffs_scan(struct sblockinfo *sbi, int n)
{
	size_t i = 0;

	if (flags & BLOCKS) {
		ffs_printpart(sbi, BLOCKS, 0, n);
		return;
	}
	if (flags & VERBOSE)
		ffs_printpart(sbi, VERBOSE, NADA, n);
	switch (ffs_checkver(sbi)) {
	case FSTYPE_FFSV1:
		/* fsize/bsize > 512/4096 and < 4096/32768. */
		if ((BLK_CNT - lastblk) == (SBLOCKSIZE / 512)) {
			i = 2;
		/* fsize/bsize 4096/32768. */
		} else if ((BLK_CNT - lastblk) == (SBLOCKSIZE / 170)) {
			i = 4;
		/* fsize/bsize 8192/65536 */
		} else if ((BLK_CNT - lastblk) == (SBLOCKSIZE / 73)) {
			i = 8;
		} else
			break;

		if (flags & LABELS)
			ffs_printpart(sbi, LABELS, i, n);
		else
			ffs_printpart(sbi, NADA, i, n);

		break;
	case FSTYPE_FFSV2:
		/*
		 * That checks for FFSv2 partitions with fragsize/blocksize:
		 * 512/4096, 1024/8192, 2048/16384, 4096/32768 and 8192/65536.
		 * Really enough for now.
		 */
		for (i = 1; i < 16; i <<= 1)
			if ((BLK_CNT - lastblk) == (daddr_t)(i * SBLOCKSIZE / 512)) {
				if (flags & LABELS)
					ffs_printpart(sbi, LABELS, i, n);
				else
					ffs_printpart(sbi, NADA, i, n);
			}
		break;
	}
}

static void
lfs_printpart(struct sblockinfo *sbi, int flag, int n)
{
	if (flags & VERBOSE)
               	(void)printf("offset: %" PRIu64 " size %" PRIu64
			" fsid %" PRIx32 "\n", sbi->lfs_off,
			lfs_sb_getsize(sbi->lfs),
			lfs_sb_getident(sbi->lfs));
	switch (flag) {
	case LABELS:
		(void)printf("X:  %9" PRIu64,
               		(lfs_sb_getsize(sbi->lfs) *
               		lfs_sb_getfsize(sbi->lfs) / 512));
		(void)printf(" %9" PRIu64, sbi->lfs_off);
		(void)printf(" 4.4LFS %6d %5d %7d # %s [LFS%d v%d]\n",
			lfs_sb_getfsize(sbi->lfs), lfs_sb_getbsize(sbi->lfs),
			lfs_sb_getnseg(sbi->lfs), sbi->lfs_path,
			sbi->lfs->lfs_is64 ? 64 : 32,
			lfs_sb_getversion(sbi->lfs));
		break;
	case BLOCKS:
		(void)printf("LFS%d v%d", sbi->lfs->lfs_is64 ? 64 : 32,
			lfs_sb_getversion(sbi->lfs));
		(void)printf(" sb at %" PRIu64, sbi->lfs_off + btodb(LFS_LABELPAD));
		(void)printf(" fsid %" PRIx32, lfs_sb_getident(sbi->lfs));
		(void)printf(" size %" PRIu64 ", last mounted on %s\n",
			(lfs_sb_getsize(sbi->lfs) *
			lfs_sb_getfsize(sbi->lfs) / 512), sbi->lfs_path);
		break;
	default:
		(void)printf("LFS%d v%d ", sbi->lfs->lfs_is64 ? 64 : 32,
			lfs_sb_getversion(sbi->lfs));
		(void)printf("at %" PRIu64, sbi->lfs_off);
		(void)printf(" size %" PRIu64 ", last mounted on %s\n",
			(lfs_sb_getsize(sbi->lfs) *
			lfs_sb_getfsize(sbi->lfs) / 512), sbi->lfs_path);
		break;
	}
}

static void
lfs_scan(struct sblockinfo *sbi, int n)
{
	size_t namesize;

	/* Check to see if the sb checksums correctly */
	if (lfs_sb_cksum(sbi->lfs) != lfs_sb_getcksum(sbi->lfs)) {
		if (flags & VERBOSE)
			printf("LFS bad superblock at %" PRIu64 "\n",
				BLK_CNT);
		return;
	}

	/* backup offset */
	lastblk = BLK_CNT - (LFS_SBPAD / 512);
	/* increment counter */
        ++sbaddr;

	if (flags & BLOCKS) {
		sbi->lfs_off = BLK_CNT - btodb(LFS_LABELPAD);
		lfs_printpart(sbi, BLOCKS, n);
		return;
	}

	switch (sbaddr) {
	/*
	 * first superblock contains the right offset, but lfs_fsmnt is
	 * empty... fortunately the next superblock address has it.
	 */
	case FIRST_SBLOCK_ADDRESS:
		/* copy partition offset */
		if ((daddr_t)sbi->lfs_off != lastblk)
			sbi->lfs_off = BLK_CNT - (LFS_LABELPAD / 512);
		break;
	case SECOND_SBLOCK_ADDRESS:
		/* copy the path of last mount */
		namesize = MIN(sizeof(sbi->lfs_path), MIN(
			       sizeof(sbi->lfs->lfs_dlfs_u.u_32.dlfs_fsmnt),
			       sizeof(sbi->lfs->lfs_dlfs_u.u_64.dlfs_fsmnt)));
		(void)memcpy(sbi->lfs_path, lfs_sb_getfsmnt(sbi->lfs),
			     namesize);
		sbi->lfs_path[namesize - 1] = '\0';
		/* print now that we have the info */
		if (flags & LABELS)
			lfs_printpart(sbi, LABELS, n);
		else
			lfs_printpart(sbi, NADA, n);
		/* clear our struct */
		(void)memset(sbi, 0, sizeof(*sbi));
		break;
	case MAX_SBLOCK_ADDRESS:
		/*
		 * reset the counter, this is the last superblock address,
		 * the next one will be another partition maybe.
		 */
		sbaddr = 0;
		break;
	default:
		break;
	}
}

static int
lfs_checkmagic(struct sblockinfo *sbinfo)
{
	switch (sbinfo->lfs->lfs_dlfs_u.u_32.dlfs_magic) {
	case LFS_MAGIC:
		sbinfo->lfs->lfs_is64 = false;
		sbinfo->lfs->lfs_dobyteswap = false;
		return 1;
	case LFS_MAGIC_SWAPPED:
		sbinfo->lfs->lfs_is64 = false;
		sbinfo->lfs->lfs_dobyteswap = true;
		return 1;
	case LFS64_MAGIC:
		sbinfo->lfs->lfs_is64 = true;
		sbinfo->lfs->lfs_dobyteswap = false;
		return 1;
	case LFS64_MAGIC_SWAPPED:
		sbinfo->lfs->lfs_is64 = true;
		sbinfo->lfs->lfs_dobyteswap = true;
		return 1;
	default:
		return 0;
	}
}

static int
scan_disk(int fd, daddr_t beg, daddr_t end, int fflags)
{
	struct sblockinfo sbinfo;
	uint8_t buf[SBLOCKSIZE * SBCOUNT];
	int n;

	n = 0;
	lastblk = -1;

	/* clear our struct before using it */
	(void)memset(&sbinfo, 0, sizeof(sbinfo));

	if (fflags & LABELS)
		(void)printf(
		    "#        size    offset fstype [fsize bsize cpg/sgs]\n");

	const daddr_t total = end - beg;
	for (blk = beg; blk <= end; blk += SBPASS) {
		if (print_info) {
			const daddr_t done = blk - beg;
			const int pcent = (int)((100.0 * done) / total);

			fprintf(stderr, "%s: done %llu of %llu blocks (%d%%)\n",
				getprogname(), (unsigned long long)done,
				(unsigned long long)total, pcent);
			print_info = 0;
		}
		if (pread(fd, buf, sizeof(buf), blk * 512) == -1) {
			if (fflag && fd >= 0)
				(void)close(fd);
			err(1, "pread");
		}

		for (n = 0; n < (SBLOCKSIZE * SBCOUNT); n += 512) {
			sbinfo.ffs = (struct fs *)&buf[n];
			sbinfo.lfs = (struct lfs *)&buf[n];

			switch (ffs_checkver(&sbinfo)) {
			case FSTYPE_FFSV1:
			case FSTYPE_FFSV2:
				ffs_scan(&sbinfo, n);
				lastblk = BLK_CNT;
				(void)memcpy(sbinfo.ffs_path,
					sbinfo.ffs->fs_fsmnt, MAXMNTLEN);
				break;
			case FSTYPE_NONE:
				/* maybe LFS? */
				if (lfs_checkmagic(&sbinfo))
					lfs_scan(&sbinfo, n);
				break;
			default:
				break;
			}
		}
	}

	if (fflag && fd >= 0)
		(void)close(fd);

	return EXIT_SUCCESS;
}


static void
usage(void)
{
	(void)fprintf(stderr,
		"Usage: %s [-blv] [-e end] [-F file] [-s start] "
		"device\n", getprogname());
	exit(EXIT_FAILURE);
}


int
main(int argc, char **argv)
{
	int ch, fd;
	const char *fpath;
	daddr_t end = -1, beg = 0;
	struct disklabel dl;

	fpath = NULL;

	setprogname(*argv);
	while ((ch = getopt(argc, argv, "be:F:ls:v")) != -1)
		switch(ch) {
		case 'b':
			flags |= BLOCKS;
			flags &= ~LABELS;
			break;
		case 'e':
			eflag = 1;
			end = atoi(optarg);
			break;
		case 'F':
			fflag = 1;
			fpath = optarg;
			break;
		case 'l':
			flags |= LABELS;
			flags &= ~BLOCKS;
			break;
		case 's':
			beg = atoi(optarg);
			break;
		case 'v':
			flags |= VERBOSE;
			break;
		default:
			usage();
			/* NOTREACHED */
		}

	argc -= optind;
	argv += optind;

	signal(SIGINFO, got_siginfo);

	if (fflag) {
		struct stat stp;

		if (stat(fpath, &stp))
			err(1, "Cannot stat `%s'", fpath);

		if (!eflag)
			end = (uint64_t)stp.st_size;

		(void)printf("Total file size: %" PRIu64 "\n\n",
		    (uint64_t)stp.st_size);

		fd = open(fpath, O_RDONLY | O_DIRECT);
	} else {
		if (argc != 1)
			usage();

		fd = opendisk(argv[0], O_RDONLY, device, sizeof(device), 0);

		if (ioctl(fd, DIOCGDINFO, &dl) == -1) {
			warn("Couldn't retrieve disklabel");
			(void)memset(&dl, 0, sizeof(dl));
			dl.d_secperunit = 0x7fffffff;
		} else {
			(void)printf("Disk: %s\n", dl.d_typename);
			(void)printf("Total sectors on disk: %" PRIu32 "\n\n",
			    dl.d_secperunit);
		}
	}

	if (!eflag && !fflag)
		end = dl.d_secperunit; /* default to max sectors */

	if (fd == -1)
		err(1, "Cannot open `%s'", device);
		/* NOTREACHED */

	return scan_disk(fd, beg, end, flags);
}