/*      $OpenBSD: powerpc64_installboot.c,v 1.10 2025/09/17 16:12:10 deraadt Exp $      */

/*
 * Copyright (c) 2011 Joel Sing <jsing@openbsd.org>
 * Copyright (c) 2010 Otto Moerbeek <otto@openbsd.org>
 * Copyright (c) 2003 Tom Cosgrove <tom.cosgrove@arches-consulting.com>
 * Copyright (c) 1997 Michael Shalayeff
 * Copyright (c) 1994 Paul Kranenburg
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Paul Kranenburg.
 * 4. 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/param.h>  /* DEV_BSIZE */
#include <sys/disklabel.h>
#include <sys/dkio.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/stat.h>

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

#include "installboot.h"

static int      create_filesystem(struct disklabel *, char);
static void     write_filesystem(struct disklabel *, char);
static int      findmbrfat(int, struct disklabel *);

char    duid[20];

void
md_init(void)
{
        stages = 1;
        stage1 = "/usr/mdec/boot";
}

void
md_loadboot(void)
{
}

void
md_prepareboot(int devfd, char *dev)
{
        struct disklabel dl;
        int part;

        /* Get and check disklabel. */
        if (ioctl(devfd, DIOCGDINFO, &dl) == -1)
                err(1, "disklabel: %s", dev);
        if (dl.d_magic != DISKMAGIC)
                errx(1, "bad disklabel magic=0x%08x", dl.d_magic);

        /* Warn on unknown disklabel types. */
        if (dl.d_type == 0)
                warnx("disklabel type unknown");

        part = findmbrfat(devfd, &dl);
        if (part != -1) {
                create_filesystem(&dl, (char)part);
                return;
        }
}

void
md_installboot(int devfd, char *dev)
{
        struct disklabel dl;
        int part;

        /* Get and check disklabel. */
        if (ioctl(devfd, DIOCGDINFO, &dl) == -1)
                err(1, "disklabel: %s", dev);
        if (dl.d_magic != DISKMAGIC)
                errx(1, "bad disklabel magic=0x%08x", dl.d_magic);

        snprintf(duid, sizeof duid,
            "%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx",
            dl.d_uid[0], dl.d_uid[1], dl.d_uid[2], dl.d_uid[3],
            dl.d_uid[4], dl.d_uid[5], dl.d_uid[6], dl.d_uid[7]);

        /* Warn on unknown disklabel types. */
        if (dl.d_type == 0)
                warnx("disklabel type unknown");

        part = findmbrfat(devfd, &dl);
        if (part != -1) {
                write_filesystem(&dl, (char)part);
                return;
        }
}

static int
create_filesystem(struct disklabel *dl, char part)
{
        static const char *newfsfmt = "/sbin/newfs -t msdos %s >/dev/null";
        struct msdosfs_args args;
        char cmd[60];
        int rslt;

        /* Newfs <duid>.<part> as msdos filesystem. */
        memset(&args, 0, sizeof(args));
        rslt = asprintf(&args.fspec,
            "%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx.%c",
            dl->d_uid[0], dl->d_uid[1], dl->d_uid[2], dl->d_uid[3],
            dl->d_uid[4], dl->d_uid[5], dl->d_uid[6], dl->d_uid[7],
            part);
        if (rslt == -1) {
                warn("bad special device");
                return rslt;
        }

        rslt = snprintf(cmd, sizeof(cmd), newfsfmt, args.fspec);
        if (rslt >= sizeof(cmd)) {
                warnx("can't build newfs command");
                free(args.fspec);
                rslt = -1;
                return rslt;
        }

        if (verbose)
                fprintf(stderr, "%s %s\n",
                    (nowrite ? "would newfs" : "newfsing"), args.fspec);
        if (!nowrite) {
                rslt = system(cmd);
                if (rslt == -1) {
                        warn("system('%s') failed", cmd);
                        free(args.fspec);
                        return rslt;
                }
        }

        free(args.fspec);
        return 0;
}

static void
write_filesystem(struct disklabel *dl, char part)
{
        static const char *fsckfmt = "/sbin/fsck -t msdos %s >/dev/null";
        struct msdosfs_args args;
        char cmd[60];
        char dir[PATH_MAX];
        char dst[PATH_MAX];
        size_t mntlen;
        int rslt;

        /* Create directory for temporary mount point. */
        strlcpy(dir, "/tmp/installboot.XXXXXXXXXX", sizeof(dst));
        if (mkdtemp(dir) == NULL)
                err(1, "mkdtemp('%s') failed", dst);
        mntlen = strlen(dir);

        /* Mount <duid>.<part> as msdos filesystem. */
        memset(&args, 0, sizeof(args));
        rslt = asprintf(&args.fspec,
            "%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx.%c",
            dl->d_uid[0], dl->d_uid[1], dl->d_uid[2], dl->d_uid[3],
            dl->d_uid[4], dl->d_uid[5], dl->d_uid[6], dl->d_uid[7],
            part);
        if (rslt == -1) {
                warn("bad special device");
                goto rmdir;
        }

        args.export_info.ex_root = -2;
        args.export_info.ex_flags = 0;
        args.flags = MSDOSFSMNT_LONGNAME;

        if (mount(MOUNT_MSDOS, dir, 0, &args) == -1) {
                /* Try fsck'ing it. */
                rslt = snprintf(cmd, sizeof(cmd), fsckfmt, args.fspec);
                if (rslt >= sizeof(cmd)) {
                        warnx("can't build fsck command");
                        rslt = -1;
                        goto rmdir;
                }
                rslt = system(cmd);
                if (rslt == -1) {
                        warn("system('%s') failed", cmd);
                        goto rmdir;
                }
                if (mount(MOUNT_MSDOS, dir, 0, &args) == -1) {
                        /* Try newfs'ing it. */
                        rslt = create_filesystem(dl, part);
                        if (rslt == -1)
                                goto rmdir;
                        rslt = mount(MOUNT_MSDOS, dir, 0, &args);
                        if (rslt == -1) {
                                warn("unable to mount MSDOS partition");
                                goto rmdir;
                        }
                }
        }

        /*
         * Copy /usr/mdec/boot to /mnt/boot.
         */
        strlcpy(dst, dir, sizeof dst);
        if (strlcat(dst, "/boot", sizeof(dst)) >= sizeof(dst)) {
                rslt = -1;
                warn("unable to build /boot path");
                goto umount;
        }
        if (verbose)
                fprintf(stderr, "%s %s to %s\n",
                    (nowrite ? "would copy" : "copying"), stage1, dst);
        if (!nowrite) {
                rslt = filecopy(stage1, dst);
                if (rslt == -1)
                        goto umount;
        }

        /*
         * Create grub.cfg
         */
        strlcpy(dst, dir, sizeof dst);
        if (strlcat(dst, "/grub.cfg", sizeof(dst)) >= sizeof(dst)) {
                rslt = -1;
                warn("unable to build /grub.cfg path");
                goto umount;
        }
        if (verbose)
                fprintf(stderr, "%s %s\n",
                    (nowrite ? "would create" : "creating"), dst);
        if (!nowrite) {
                FILE *f;

                f = fopen(dst, "w+");
                if (f == NULL)
                        goto umount;
                fprintf(f,
                    "menuentry \"OpenBSD\" {\n"
                    "\tlinux /boot bootduid=%s\n"
                    "\tinitrd /boot\n"
                    "}\n", duid);
                fclose(f);
        }

        rslt = 0;

umount:
        dir[mntlen] = '\0';
        if (unmount(dir, MNT_FORCE) == -1)
                err(1, "unmount('%s') failed", dir);

rmdir:
        free(args.fspec);
        dst[mntlen] = '\0';
        if (rmdir(dir) == -1)
                err(1, "rmdir('%s') failed", dir);

        if (rslt == -1)
                exit(1);
}

int
findmbrfat(int devfd, struct disklabel *dl)
{
        struct dos_partition     dp[NDOSPART];
        ssize_t                  len;
        u_int64_t                start = 0;
        int                      i;
        u_int8_t                *secbuf;

        if ((secbuf = malloc(dl->d_secsize)) == NULL)
                err(1, NULL);

        /* Read MBR. */
        len = pread(devfd, secbuf, dl->d_secsize, 0);
        if (len != dl->d_secsize)
                err(4, "can't read mbr");
        memcpy(dp, &secbuf[DOSPARTOFF], sizeof(dp));

        for (i = 0; i < NDOSPART; i++) {
                if (dp[i].dp_typ == DOSPTYP_UNUSED)
                        continue;
                if (dp[i].dp_typ == DOSPTYP_FAT16L ||
                    dp[i].dp_typ == DOSPTYP_FAT32L ||
                    dp[i].dp_typ == DOSPTYP_FAT16B)
                        start = letoh32(dp[i].dp_start);
        }

        free(secbuf);

        if (start) {
                for (i = 0; i < MAXPARTITIONS; i++) {
                        if (DL_GETPSIZE(&dl->d_partitions[i]) > 0 &&
                            DL_GETPOFFSET(&dl->d_partitions[i]) == start)
                                return (DL_PARTNUM2NAME(i));
                }
        }

        return (-1);
}