/*      $NetBSD: disklabel.c,v 1.8 2025/11/19 09:43:27 nia Exp $        */

/*
 * Copyright (c) 1995 Waldi Ravens
 * 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.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * 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.
 */

#include <sys/types.h>
#include <sys/param.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <sys/disklabel.h>
#include <machine/ahdilabel.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <fcntl.h>
#include <err.h>

#if (BBSIZE < MINBBSIZE)
#error BBSIZE is smaller than MINBBSIZE
#endif

struct ahdilabel {
        u_int            nsecs;
        daddr_t          bslst;
        daddr_t          bslend;
        u_int            nroots;
        daddr_t          *roots;
        u_int            nparts;
        struct ahdi_part *parts;
};

u_int   dkcksum(struct disklabel *);
uint32_t readdisklabel(char *, struct disklabel *);

static int  bsd_label(int, off_t, struct disklabel *);
static int  ahdi_label(int, uint32_t *, struct disklabel *);
static int  ahdi_getparts(int, daddr_t, daddr_t, struct ahdilabel *);

u_int
dkcksum (struct disklabel *dl)
{
        uint16_t sum  = 0,
                 *st  = (uint16_t *)dl,
                 *end = (uint16_t *)&dl->d_partitions[dl->d_npartitions];

        while (st < end)
                sum ^= *st++;
        return sum;
}

uint32_t
readdisklabel(char *fn, struct disklabel *dl)
{
        int              fd, e;
        uint32_t         bbsec;

        memset(dl, 0, sizeof *dl);

        if ((fd = open(fn, O_RDONLY)) < 0)
                err(EXIT_FAILURE, "%s", fn);

        /* Try NetBSD/Atari format first */
        if ((e = bsd_label(fd, (off_t)0, dl)) < 0)
                err(EXIT_FAILURE, "%s", fn);
        if (e == 0)
                return 0;

        /* Try unprotected AHDI format last */
        if ((e = ahdi_label(fd, &bbsec, dl)) < 0)
                err(EXIT_FAILURE, "%s", fn);
        if (e == 0)
                return bbsec;

        warnx("%s: Unknown disk label format.", fn);
        return NO_BOOT_BLOCK;
}

static int
bsd_label(int fd, off_t offs, struct disklabel *label)
{
        struct bootblock bb;
        struct disklabel *p;

        if (lseek(fd, offs, SEEK_SET) != offs)
                return -1;
        if (read(fd, &bb, sizeof(bb)) != sizeof(bb))
                return -1;

        p = (struct disklabel *)bb.bb_label;
        if ((offs == 0 && bb.bb_magic != NBDAMAGIC) ||
            (offs != 0 && bb.bb_magic != AHDIMAGIC) ||
            p->d_npartitions > MAXPARTITIONS ||
            p->d_magic2 != DISKMAGIC ||
            p->d_magic  != DISKMAGIC ||
            dkcksum(p)  != 0) {
                return 1;
        }

        *label = *p;
        return 0;
}

static int
ahdi_label(int fd, uint32_t *bbsec, struct disklabel *label)
{
        struct ahdilabel al;
        u_int            i, j;
        int              e;

        memset(&al, 0, sizeof(al));
        if ((e = ahdi_getparts(fd, AHDI_BBLOCK, AHDI_BBLOCK, &al)) != 0)
                return e;

        /*
         * Perform sanity checks.
         */
        if (al.bslst == 0 || al.bslend == 0)
                return 1;
        if (al.nsecs == 0 || al.nparts == 0)
                return 1;
        if (al.nparts > AHDI_MAXPARTS)
                warnx("Too many AHDI partitions (%u).", al.nparts);
        for (i = 0; i < al.nparts; ++i) {
                struct ahdi_part *p1 = &al.parts[i];
                for (j = 0; j < al.nroots; ++j) {
                        daddr_t aux = al.roots[j];
                        if (aux >= p1->ap_st && aux <= p1->ap_end)
                                return 1;
                }
                for (j = i + 1; j < al.nparts; ++j) {
                        struct ahdi_part *p2 = &al.parts[j];
                        if (p1->ap_st >= p2->ap_st && p1->ap_st <= p2->ap_end)
                                return 1;
                        if (p2->ap_st >= p1->ap_st && p2->ap_st <= p1->ap_end)
                                return 1;
                }
                if (p1->ap_st >= al.bslst && p1->ap_st <= al.bslend)
                        return 1;
                if (al.bslst >= p1->ap_st && al.bslst <= p1->ap_end)
                        return 1;
        }

        /*
         * Search for a NetBSD boot block
         */
        for (i = 0; i < al.nparts; ++i) {
                struct ahdi_part *pd = &al.parts[i];
                u_int id;

                memcpy(&id, &pd->ap_flg, sizeof (id));
                if (id == AHDI_PID_NBD || id == AHDI_PID_RAW) {
                        off_t   offs = pd->ap_st * AHDI_BSIZE;
                        if ((e = bsd_label(fd, offs, label)) < 0)
                                return e;
                        if (e == 0) {
                                *bbsec = pd->ap_st;     /* got it */
                                return 0;
                        }
                }
        }
        *bbsec = NO_BOOT_BLOCK; /* AHDI label, no NetBSD boot block */
        return 0;
}

static int
ahdi_getparts(int fd, daddr_t rsec, daddr_t esec, struct ahdilabel *alab)
{
        struct ahdi_part *part, *end;
        struct ahdi_root root;
        off_t            ro;

        ro = rsec * AHDI_BSIZE;
        if (lseek(fd, ro, SEEK_SET) != ro) {
                off_t   mend = lseek(fd, 0, SEEK_END);
                if (mend == -1 || mend > ro)
                        return -1;
                return 1;
        }
        if (read(fd, &root, sizeof(root)) != sizeof(root))
                return -1;

        if (rsec == AHDI_BBLOCK)
                end = &root.ar_parts[AHDI_MAXRPD];
        else
                end = &root.ar_parts[AHDI_MAXARPD];
        for (part = root.ar_parts; part < end; ++part) {
                u_int   id;

                memcpy(&id, &part->ap_flg, sizeof (id));
                if ((id & 0x01000000) == 0)
                        continue;
                if ((id &= 0x00ffffff) == AHDI_PID_XGM) {
                        int     e;
                        daddr_t aux = part->ap_st + esec;
                        alab->roots = realloc(alab->roots,
                            (alab->nroots + 1) * sizeof(*alab->roots));
                        alab->roots[alab->nroots++] = aux;
                        e = ahdi_getparts(fd, aux,
                            esec == AHDI_BBLOCK ? aux : esec, alab);
                        if (e != 0)
                                return e;
                } else {
                        struct ahdi_part *p;
                        alab->parts = realloc(alab->parts,
                            (alab->nparts + 1) * sizeof(*alab->parts));
                        p = &alab->parts[alab->nparts++];
                        memcpy(&p->ap_flg, &id, sizeof (id));
                        p->ap_st = part->ap_st + rsec;
                        p->ap_end  = p->ap_st + part->ap_size - 1;
                }
        }
        alab->nsecs  = root.ar_hdsize;
        alab->bslst  = root.ar_bslst;
        alab->bslend = root.ar_bslst + root.ar_bslsize - 1;
        return 0;
}