/* $NetBSD: next68k.c,v 1.10 2023/02/14 20:27:17 andvar Exp $ */

/*-
 * Copyright (c) 2003 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by David Laight and Christian Limpach.
 *
 * 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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.
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif

#include <sys/cdefs.h>
#if !defined(__lint)
__RCSID("$NetBSD: next68k.c,v 1.10 2023/02/14 20:27:17 andvar Exp $");
#endif /* !__lint */

#include <sys/param.h>

#include <assert.h>
#include <err.h>
#include <md5.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "installboot.h"

static uint16_t nextstep_checksum(const void *, const void *);
static int next68k_setboot(ib_params *);

struct ib_mach ib_mach_next68k = {
        .name           =       "next68k",
        .setboot        =       next68k_setboot,
        .clearboot      =       no_clearboot,
        .editboot       =       no_editboot,
};

static uint16_t
nextstep_checksum(const void *vbuf, const void *vlimit)
{
        const uint16_t *buf = vbuf;
        const uint16_t *limit = vlimit;
        u_int sum = 0;

        while (buf < limit) {
                sum += be16toh(*buf++);
        }
        sum += (sum >> 16);
        return (sum & 0xffff);
}

static int
next68k_setboot(ib_params *params)
{
        int retval, labelupdated;
        uint8_t *bootbuf;
        size_t bootsize;
        ssize_t rv;
        uint32_t cd_secsize;
        int sec_netonb_mult;
        struct next68k_disklabel *next68klabel;
        uint16_t *checksum;
        uint32_t fp, b0, b1;

        assert(params != NULL);
        assert(params->fsfd != -1);
        assert(params->filesystem != NULL);
        assert(params->s1fd != -1);
        assert(params->stage1 != NULL);

        retval = 0;
        labelupdated = 0;
        bootbuf = NULL;

        next68klabel = malloc(NEXT68K_LABEL_SIZE);
        if (next68klabel == NULL) {
                warn("Allocating %lu bytes", (unsigned long)NEXT68K_LABEL_SIZE);
                goto done;
        }

        /*
         * Read in the next68k disklabel
         */
        rv = pread(params->fsfd, next68klabel, NEXT68K_LABEL_SIZE,
            NEXT68K_LABEL_SECTOR * params->sectorsize + NEXT68K_LABEL_OFFSET);
        if (rv == -1) {
                warn("Reading `%s'", params->filesystem);
                goto done;
        }
        if (rv != NEXT68K_LABEL_SIZE) {
                warnx("Reading `%s': short read", params->filesystem);
                goto done;
        }
        if (be32toh(next68klabel->cd_version) == NEXT68K_LABEL_CD_V3) {
                checksum = &next68klabel->NEXT68K_LABEL_cd_v3_checksum;
        } else {
                checksum = &next68klabel->cd_checksum;
        }
        if (nextstep_checksum (next68klabel, checksum) !=
            be16toh(*checksum)) {
                warn("Disklabel checksum invalid on `%s'",
                    params->filesystem);
                goto done;
        }

        cd_secsize = be32toh(next68klabel->cd_secsize);
        sec_netonb_mult = (cd_secsize / params->sectorsize);

        /*
         * Allocate a buffer, with space to round up the input file
         * to the next block size boundary, and with space for the boot
         * block.
         */
        bootsize = roundup(params->s1stat.st_size, cd_secsize);

        bootbuf = malloc(bootsize);
        if (bootbuf == NULL) {
                warn("Allocating %zu bytes", bootsize);
                goto done;
        }
        memset(bootbuf, 0, bootsize);

        /*
         * Read the file into the buffer.
         */
        rv = pread(params->s1fd, bootbuf, params->s1stat.st_size, 0);
        if (rv == -1) {
                warn("Reading `%s'", params->stage1);
                goto done;
        } else if (rv != params->s1stat.st_size) {
                warnx("Reading `%s': short read", params->stage1);
                goto done;
        }

        if (bootsize > be16toh(next68klabel->cd_front) * cd_secsize -
            NEXT68K_LABEL_SIZE) {
                warnx("Boot program is larger than front porch space");
                goto done;
        }

        fp = be16toh(next68klabel->cd_front);
        b0 = be32toh(next68klabel->cd_boot_blkno[0]);
        b1 = be32toh(next68klabel->cd_boot_blkno[1]);

        if (b0 > fp)
                b0 = fp;
        if (b1 > fp)
                b1 = fp;
        if (((bootsize / cd_secsize) > b1 - b0) ||
            ((bootsize / cd_secsize) > fp - b1)) {
                if (2 * bootsize > (fp * cd_secsize - NEXT68K_LABEL_SIZE))
                        /* can only fit one copy */
                        b0 = b1 = NEXT68K_LABEL_SIZE / cd_secsize;
                else {
                        if (2 * bootsize > (fp * cd_secsize -
                                NEXT68K_LABEL_DEFAULTBOOT0_1 *
                                params->sectorsize))
                                /* can fit two copies starting after label */
                                b0 = NEXT68K_LABEL_SIZE / cd_secsize;
                        else
                                /* can fit two copies starting at default 1 */
                                b0 = NEXT68K_LABEL_DEFAULTBOOT0_1 /
                                        sec_netonb_mult;
                        /* try to fit 2nd copy at default 2 */
                        b1 = NEXT68K_LABEL_DEFAULTBOOT0_2 / sec_netonb_mult;
                        if (fp < b1)
                                b1 = fp;
                        if (bootsize / cd_secsize > (fp - b1))
                                /* fit 2nd copy before front porch */
                                b1 = fp - bootsize / cd_secsize;
                }
        }
        if (next68klabel->cd_boot_blkno[0] != (int32_t)htobe32(b0)) {
                next68klabel->cd_boot_blkno[0] = htobe32(b0);
                labelupdated = 1;
        }
        if (next68klabel->cd_boot_blkno[1] != (int32_t)htobe32(b1)) {
                next68klabel->cd_boot_blkno[1] = htobe32(b1);
                labelupdated = 1;
        }
        if (params->flags & IB_VERBOSE)
                printf("Boot program locations%s: %d %d\n",
                    labelupdated ? " updated" : "", b0 * sec_netonb_mult,
                    b1 * sec_netonb_mult);

        if (params->flags & IB_NOWRITE) {
                retval = 1;
                goto done;
        }

        /*
         * Write the updated next68k disklabel
         */
        if (labelupdated) {
                if (params->flags & IB_VERBOSE)
                        printf ("Writing updated label\n");
                *checksum = htobe16(nextstep_checksum (next68klabel,
                                        checksum));
                rv = pwrite(params->fsfd, next68klabel, NEXT68K_LABEL_SIZE,
                    NEXT68K_LABEL_SECTOR * params->sectorsize +
                    NEXT68K_LABEL_OFFSET);
                if (rv == -1) {
                        warn("Writing `%s'", params->filesystem);
                        goto done;
                }
                if (rv != NEXT68K_LABEL_SIZE) {
                        warnx("Writing `%s': short write", params->filesystem);
                        goto done;
                }
        }

        b0 *= sec_netonb_mult;
        b1 *= sec_netonb_mult;

        /*
         * Write boot program to locations b0 and b1 (if different).
         */
        for (;;) {
                if (params->flags & IB_VERBOSE)
                        printf ("Writing boot program at %d\n", b0);
                rv = pwrite(params->fsfd, bootbuf, bootsize,
                    b0 * params->sectorsize);
                if (rv == -1) {
                        warn("Writing `%s' at %d", params->filesystem, b0);
                        goto done;
                }
                if ((size_t)rv != bootsize) {
                        warnx("Writing `%s' at %d: short write",
                            params->filesystem, b0);
                        goto done;
                }
                if (b0 == b1)
                        break;
                b0 = b1;
        }

        retval = 1;

 done:
        if (bootbuf)
                free(bootbuf);
        if (next68klabel)
                free(next68klabel);
        return retval;
}