/* $NetBSD: scan_ffs.c,v 1.38 2025/12/24 15:48:27 thorpej 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 1.38 2025/12/24 15:48:27 thorpej 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>

#ifdef SUPPORT_LFS
#include <ufs/lfs/lfs.h>
#include <ufs/lfs/lfs_accessors.h>
#include <ufs/lfs/lfs_extern.h>
#endif /* SUPPORT_LFS */

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

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <err.h>
#include <util.h>
#include <paths.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;
#ifdef SUPPORT_LFS
static int      sbaddr = 0; /* counter for the LFS superblocks */
#endif

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 *);

#ifdef SUPPORT_LFS
/* LFS functions */
static void     lfs_printpart(struct sblockinfo *, int, int);
static void     lfs_scan(struct sblockinfo *, int);
#endif /* SUPPORT_LFS */

/* 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_SWAPPED:
                case FS_UFS2_MAGIC_SWAPPED:
                case FS_UFS2EA_MAGIC_SWAPPED:
                        ffs_sb_swap(sbi->ffs, sbi->ffs);
                        break;
        }

        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_UFS2EA_MAGIC:
                case FS_UFS2_MAGIC_SWAPPED:
                case FS_UFS2EA_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;
        }
}

#ifdef SUPPORT_LFS
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;
        }
}
#endif /* SUPPORT_LFS */

static void
show_status(uintmax_t beg, uintmax_t total)
{
        static int ttyfd = -2;
        char buf[2048];
        const uintmax_t done = blk - beg;
        const double pcent = (100.0 * done) / total;
        int n;

        if (ttyfd == -2)
                ttyfd = open(_PATH_TTY, O_RDWR | O_CLOEXEC);

        if (ttyfd == -1)
                return;

        n = snprintf(buf, sizeof(buf), "%s: done %ju of %ju blocks (%3.2f%%)\n", 
            getprogname(), done, total, pcent);

        if (n <= 0)
                return;
        write(ttyfd, buf, (size_t)n);
}

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) {
                        show_status(beg, total);
                        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:
#ifdef SUPPORT_LFS
                                /* maybe LFS? */
                                if (lfs_checkmagic(&sbinfo))
                                        lfs_scan(&sbinfo, n);
#endif /* SUPPORT_LFS */
                                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);
}