/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright 2012 Milan Jurik. All rights reserved.
 * Copyright 2016 Toomas Soome <tsoome@me.com>
 * Copyright 2016 Nexenta Systems, Inc. All rights reserved.
 */

#include <stdio.h>
#include <stdlib.h>
#include <libgen.h>
#include <malloc.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <strings.h>
#include <libintl.h>
#include <locale.h>
#include <errno.h>
#include <libfdisk.h>
#include <stdarg.h>
#include <assert.h>

#include <sys/mount.h>
#include <sys/mnttab.h>
#include <sys/dktp/fdisk.h>
#include <sys/dkio.h>
#include <sys/vtoc.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/multiboot.h>
#include <sys/sysmacros.h>
#include <sys/efi_partition.h>

#include <libnvpair.h>
#include <libfstyp.h>

#include "message.h"
#include "installgrub.h"
#include "./../common/bblk_einfo.h"
#include "./../common/boot_utils.h"
#include "./../common/mboot_extra.h"
#include "getresponse.h"

#ifndef TEXT_DOMAIN
#define TEXT_DOMAIN     "SUNW_OST_OSCMD"
#endif

/*
 * Variables to track installgrub desired mode of operation.
 * 'nowrite' and 'boot_debug' come from boot_common.h.
 */
static boolean_t write_mbr = B_FALSE;
static boolean_t force_mbr = B_FALSE;
static boolean_t force_update = B_FALSE;
static boolean_t do_getinfo = B_FALSE;
static boolean_t do_version = B_FALSE;
static boolean_t do_mirror_bblk = B_FALSE;
static boolean_t strip = B_FALSE;
static boolean_t verbose_dump = B_FALSE;

/* Installing the bootblock is the default operation. */
static boolean_t do_install = B_TRUE;

/* Versioning string, if present. */
static char *update_str;

/*
 * Temporary buffer to store the first 32K of data looking for a multiboot
 * signature.
 */
char    mboot_scan[MBOOT_SCAN_SIZE];

/* Function prototypes. */
static void check_options(char *);
static int handle_install(char *, char **);
static int handle_mirror(char *, char **);
static int handle_getinfo(char *, char **);
static int commit_to_disk(ig_data_t *, char *);
static int init_device(ig_device_t *, char *path);
static void cleanup_device(ig_device_t *);
static void cleanup_stage2(ig_stage2_t *);
static int get_start_sector(ig_device_t *);
static int get_disk_fd(ig_device_t *device);
static int get_raw_partition_fd(ig_device_t *);
static char *get_raw_partition_path(ig_device_t *);
static int propagate_bootblock(ig_data_t *, ig_data_t *, char *);
static int find_x86_bootpar(struct mboot *, int *, uint32_t *);
static int write_stage2(ig_data_t *);
static int write_stage1(ig_data_t *);
static void usage(char *);
static int read_stage1_from_file(char *, ig_data_t *);
static int read_stage2_from_file(char *, ig_data_t *);
static int read_stage1_from_disk(int, char *);
static int read_stage2_from_disk(int, ig_stage2_t *, int);
static int prepare_stage1(ig_data_t *);
static int prepare_stage2(ig_data_t *, char *);
static void prepare_fake_multiboot(ig_stage2_t *);
static void add_stage2_einfo(ig_stage2_t *, char *updt_str);
static boolean_t is_update_necessary(ig_data_t *, char *);

extern int read_stage2_blocklist(int, unsigned int *);

int
main(int argc, char *argv[])
{
        int     opt;
        int     params = 3;
        int     ret;
        char    **handle_args;
        char    *progname;

        (void) setlocale(LC_ALL, "");
        (void) textdomain(TEXT_DOMAIN);
        if (init_yes() < 0) {
                (void) fprintf(stderr, gettext(ERR_MSG_INIT_YES),
                    strerror(errno));
                exit(BC_ERROR);
        }

        /*
         * retro-compatibility: installing the bootblock is the default
         * and there is no switch for it.
         */
        do_install = B_TRUE;

        while ((opt = getopt(argc, argv, "dVMFfmneiu:")) != EOF) {
                switch (opt) {
                case 'm':
                        write_mbr = B_TRUE;
                        break;
                case 'n':
                        nowrite = B_TRUE;
                        break;
                case 'f':
                        force_mbr = B_TRUE;
                        break;
                case 'i':
                        do_getinfo = B_TRUE;
                        do_install = B_FALSE;
                        params = 1;
                        break;
                case 'V':
                        verbose_dump = B_TRUE;
                        break;
                case 'd':
                        boot_debug = B_TRUE;
                        break;
                case 'F':
                        force_update = B_TRUE;
                        break;
                case 'e':
                        strip = B_TRUE;
                        break;
                case 'M':
                        do_mirror_bblk = B_TRUE;
                        do_install = B_FALSE;
                        params = 2;
                        break;
                case 'u':
                        do_version = B_TRUE;

                        update_str = malloc(strlen(optarg) + 1);
                        if (update_str == NULL) {
                                (void) fprintf(stderr, gettext("Unable to "
                                    "allocate memory\n"));
                                exit(BC_ERROR);
                        }
                        (void) strlcpy(update_str, optarg, strlen(optarg) + 1);
                        break;
                default:
                        /* fall through to process non-optional args */
                        break;
                }
        }

        /* check arguments */
        if (argc != optind + params) {
                usage(argv[0]);
                exit(BC_ERROR);
        }

        /*
         * clean up options (and bail out if an unrecoverable combination is
         * requested.
         */
        progname = argv[0];
        check_options(progname);
        handle_args = argv + optind;

        if (nowrite)
                (void) fprintf(stdout, DRY_RUN);

        if (do_getinfo) {
                ret = handle_getinfo(progname, handle_args);
        } else if (do_mirror_bblk) {
                ret = handle_mirror(progname, handle_args);
        } else {
                ret = handle_install(progname, handle_args);
        }
        return (ret);
}

#define MEANINGLESS_OPT gettext("%s specified but meaningless, ignoring\n")
static void
check_options(char *progname)
{
        if (do_getinfo && do_mirror_bblk) {
                (void) fprintf(stderr, gettext("Only one of -M and -i can be "
                    "specified at the same time\n"));
                usage(progname);
                exit(BC_ERROR);
        }

        if (do_mirror_bblk) {
                /*
                 * -u and -F may actually reflect a user intent that is not
                 * correct with this command (mirror can be interpreted
                 * "similar" to install. Emit a message and continue.
                 * -e and -V have no meaning, be quiet here and only report the
                 * incongruence if a debug output is requested.
                 */
                if (do_version) {
                        (void) fprintf(stderr, MEANINGLESS_OPT, "-u");
                        do_version = B_FALSE;
                }
                if (force_update) {
                        (void) fprintf(stderr, MEANINGLESS_OPT, "-F");
                        force_update = B_FALSE;
                }
                if (strip || verbose_dump) {
                        BOOT_DEBUG(MEANINGLESS_OPT, "-e|-V");
                        strip = B_FALSE;
                        verbose_dump = B_FALSE;
                }
        }

        if (do_getinfo) {
                if (write_mbr || force_mbr || do_version || force_update) {
                        BOOT_DEBUG(MEANINGLESS_OPT, "-m|-f|-u|-F");
                        write_mbr = force_mbr = do_version = B_FALSE;
                        force_update = B_FALSE;
                }
        }
}

/*
 * Install a new stage1/stage2 pair on the specified device. handle_install()
 * expects argv to contain 3 parameters (the path to stage1, the path to stage2,
 * the target device).
 *
 * Returns:     BC_SUCCESS - if the installation is successful
 *              BC_ERROR   - if the installation failed
 *              BC_NOUPDT  - if no installation was performed because the GRUB
 *                           version currently installed is more recent than the
 *                           supplied one.
 *
 */
static int
handle_install(char *progname, char **argv)
{
        ig_data_t       install_data;
        char            *stage1_path = NULL;
        char            *stage2_path = NULL;
        char            *device_path = NULL;
        int             ret = BC_ERROR;

        stage1_path = strdup(argv[0]);
        stage2_path = strdup(argv[1]);
        device_path = strdup(argv[2]);

        bzero(&install_data, sizeof (ig_data_t));

        if (!stage1_path || !stage2_path || !device_path) {
                (void) fprintf(stderr, gettext("Missing parameter"));
                usage(progname);
                goto out;
        }

        BOOT_DEBUG("stage1 path: %s, stage2 path: %s, device: %s\n",
            stage1_path, stage2_path, device_path);

        if (init_device(&install_data.device, device_path) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Unable to gather device "
                    "information for %s\n"), device_path);
                goto out;
        }

        /* read in stage1 and stage2. */
        if (read_stage1_from_file(stage1_path, &install_data) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Error opening %s\n"),
                    stage1_path);
                goto out_dev;
        }

        if (read_stage2_from_file(stage2_path, &install_data) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Error opening %s\n"),
                    stage2_path);
                goto out_dev;
        }

        /* We do not support versioning on PCFS. */
        if (is_bootpar(install_data.device.type) && do_version)
                do_version = B_FALSE;

        /*
         * is_update_necessary() will take care of checking if versioning and/or
         * forcing the update have been specified. It will also emit a warning
         * if a non-versioned update is attempted over a versioned bootblock.
         */
        if (!is_update_necessary(&install_data, update_str)) {
                (void) fprintf(stderr, gettext("GRUB version installed "
                    "on %s is more recent or identical\n"
                    "Use -F to override or install without the -u option\n"),
                    device_path);
                ret = BC_NOUPDT;
                goto out_dev;
        }
        /*
         * We get here if:
         * - the installed GRUB version is older than the one about to be
         *   installed.
         * - no versioning string has been passed through the command line.
         * - a forced update is requested (-F).
         */
        BOOT_DEBUG("Ready to commit to disk\n");
        ret = commit_to_disk(&install_data, update_str);

out_dev:
        cleanup_device(&install_data.device);
out:
        free(stage1_path);
        free(stage2_path);
        free(device_path);
        return (ret);
}

/*
 * Retrieves from a device the extended information (einfo) associated to the
 * installed stage2.
 * Expects one parameter, the device path, in the form: /dev/rdsk/c?[t?]d?s0.
 * Returns:
 *        - BC_SUCCESS (and prints out einfo contents depending on 'flags')
 *        - BC_ERROR (on error)
 *        - BC_NOEINFO (no extended information available)
 */
static int
handle_getinfo(char *progname, char **argv)
{
        ig_data_t       data;
        ig_stage2_t     *stage2 = &data.stage2;
        ig_device_t     *device = &data.device;
        bblk_einfo_t    *einfo;
        uint8_t         flags = 0;
        uint32_t        size;
        char            *device_path;
        int             retval = BC_ERROR;
        int             ret;

        device_path = strdup(argv[0]);
        if (!device_path) {
                (void) fprintf(stderr, gettext("Missing parameter"));
                usage(progname);
                goto out;
        }

        bzero(&data, sizeof (ig_data_t));
        BOOT_DEBUG("device path: %s\n", device_path);

        if (init_device(device, device_path) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Unable to gather device "
                    "information for %s\n"), device_path);
                goto out_dev;
        }

        if (is_bootpar(device->type)) {
                (void) fprintf(stderr, gettext("Versioning not supported on "
                    "PCFS\n"));
                goto out_dev;
        }

        ret = read_stage2_from_disk(device->part_fd, stage2, device->type);
        if (ret == BC_ERROR) {
                (void) fprintf(stderr, gettext("Error reading stage2 from "
                    "%s\n"), device_path);
                goto out_dev;
        }

        if (ret == BC_NOEXTRA) {
                (void) fprintf(stdout, gettext("No multiboot header found on "
                    "%s, unable to locate extra information area\n"),
                    device_path);
                retval = BC_NOEINFO;
                goto out_dev;
        }

        einfo = find_einfo(stage2->extra, stage2->extra_size);
        if (einfo == NULL) {
                retval = BC_NOEINFO;
                (void) fprintf(stderr, gettext("No extended information "
                    "found\n"));
                goto out_dev;
        }

        /* Print the extended information. */
        if (strip)
                flags |= EINFO_EASY_PARSE;
        if (verbose_dump)
                flags |= EINFO_PRINT_HEADER;

        size = stage2->buf_size - P2ROUNDUP(stage2->file_size, 8);
        print_einfo(flags, einfo, size);
        retval = BC_SUCCESS;

out_dev:
        cleanup_device(&data.device);
out:
        free(device_path);
        return (retval);
}

/*
 * Attempt to mirror (propagate) the current stage2 over the attaching disk.
 *
 * Returns:
 *      - BC_SUCCESS (a successful propagation happened)
 *      - BC_ERROR (an error occurred)
 *      - BC_NOEXTRA (it is not possible to dump the current bootblock since
 *                      there is no multiboot information)
 */
static int
handle_mirror(char *progname, char **argv)
{
        ig_data_t       curr_data;
        ig_data_t       attach_data;
        ig_device_t     *curr_device = &curr_data.device;
        ig_device_t     *attach_device = &attach_data.device;
        ig_stage2_t     *stage2_curr = &curr_data.stage2;
        ig_stage2_t     *stage2_attach = &attach_data.stage2;
        bblk_einfo_t    *einfo_curr = NULL;
        char            *curr_device_path;
        char            *attach_device_path;
        char            *updt_str = NULL;
        int             retval = BC_ERROR;
        int             ret;

        curr_device_path = strdup(argv[0]);
        attach_device_path = strdup(argv[1]);

        if (!curr_device_path || !attach_device_path) {
                (void) fprintf(stderr, gettext("Missing parameter"));
                usage(progname);
                goto out;
        }
        BOOT_DEBUG("Current device path is: %s, attaching device path is: "
            " %s\n", curr_device_path, attach_device_path);

        bzero(&curr_data, sizeof (ig_data_t));
        bzero(&attach_data, sizeof (ig_data_t));

        if (init_device(curr_device, curr_device_path) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Unable to gather device "
                    "information for %s (current device)\n"), curr_device_path);
                goto out_currdev;
        }

        if (init_device(attach_device, attach_device_path) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Unable to gather device "
                    "information for %s (attaching device)\n"),
                    attach_device_path);
                goto out_devs;
        }

        if (is_bootpar(curr_device->type) || is_bootpar(attach_device->type)) {
                (void) fprintf(stderr, gettext("boot block mirroring is not "
                    "supported on PCFS\n"));
                goto out_devs;
        }

        ret = read_stage2_from_disk(curr_device->part_fd, stage2_curr,
            curr_device->type);
        if (ret == BC_ERROR) {
                BOOT_DEBUG("Error reading first stage2 blocks from %s\n",
                    curr_device->path);
                retval = BC_ERROR;
                goto out_devs;
        }

        if (ret == BC_NOEXTRA) {
                BOOT_DEBUG("No multiboot header found on %s, unable to grab "
                    "stage2\n", curr_device->path);
                retval = BC_NOEXTRA;
                goto out_devs;
        }

        einfo_curr = find_einfo(stage2_curr->extra, stage2_curr->extra_size);
        if (einfo_curr != NULL)
                updt_str = einfo_get_string(einfo_curr);

        write_mbr = B_TRUE;
        force_mbr = B_TRUE;
        retval = propagate_bootblock(&curr_data, &attach_data, updt_str);
        cleanup_stage2(stage2_curr);
        cleanup_stage2(stage2_attach);

out_devs:
        cleanup_device(attach_device);
out_currdev:
        cleanup_device(curr_device);
out:
        free(curr_device_path);
        free(attach_device_path);
        return (retval);
}

static int
commit_to_disk(ig_data_t *install, char *updt_str)
{
        assert(install != NULL);
        /*
         * vanilla stage1 and stage2 need to be updated at runtime.
         * Update stage2 before stage1 because stage1 needs to know the first
         * sector stage2 will be written to.
         */
        if (prepare_stage2(install, updt_str) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Error building stage2\n"));
                return (BC_ERROR);
        }
        if (prepare_stage1(install) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Error building stage1\n"));
                return (BC_ERROR);
        }

        /* Write stage2 out to disk. */
        if (write_stage2(install) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Error writing stage2 to "
                    "disk\n"));
                return (BC_ERROR);
        }

        /* Write stage1 to disk and, if requested, to the MBR. */
        if (write_stage1(install) != BC_SUCCESS) {
                (void) fprintf(stderr, gettext("Error writing stage1 to "
                    "disk\n"));
                return (BC_ERROR);
        }

        return (BC_SUCCESS);
}

/*
 * Propagate the bootblock on the source disk to the destination disk and
 * version it with 'updt_str' in the process. Since we cannot trust any data
 * on the attaching disk, we do not perform any specific check on a potential
 * target extended information structure and we just blindly update.
 */
static int
propagate_bootblock(ig_data_t *source, ig_data_t *target, char *updt_str)
{
        ig_device_t     *src_device = &source->device;
        ig_device_t     *dest_device = &target->device;
        ig_stage2_t     *src_stage2 = &source->stage2;
        ig_stage2_t     *dest_stage2 = &target->stage2;
        uint32_t        buf_size;
        int             retval;

        assert(source != NULL);
        assert(target != NULL);

        /* read in stage1 from the source disk. */
        if (read_stage1_from_disk(src_device->part_fd, target->stage1_buf)
            != BC_SUCCESS)
                return (BC_ERROR);

        /* Prepare target stage2 for commit_to_disk. */
        cleanup_stage2(dest_stage2);

        if (updt_str != NULL)
                do_version = B_TRUE;
        else
                do_version = B_FALSE;

        buf_size = src_stage2->file_size + SECTOR_SIZE;

        dest_stage2->buf_size = P2ROUNDUP(buf_size, SECTOR_SIZE);
        dest_stage2->buf = malloc(dest_stage2->buf_size);
        if (dest_stage2->buf == NULL) {
                perror(gettext("Memory allocation failed"));
                return (BC_ERROR);
        }
        dest_stage2->file = dest_stage2->buf;
        dest_stage2->file_size = src_stage2->file_size;
        memcpy(dest_stage2->file, src_stage2->file, dest_stage2->file_size);
        dest_stage2->extra = dest_stage2->buf +
            P2ROUNDUP(dest_stage2->file_size, 8);

        /* If we get down here we do have a mboot structure. */
        assert(src_stage2->mboot);

        dest_stage2->mboot_off = src_stage2->mboot_off;
        dest_stage2->mboot = (multiboot_header_t *)(dest_stage2->buf +
            dest_stage2->mboot_off);

        (void) fprintf(stdout, gettext("Propagating %s stage1/stage2 to %s\n"),
            src_device->path, dest_device->path);
        retval = commit_to_disk(target, updt_str);

        return (retval);
}

/*
 * open the device and fill the various members of ig_device_t.
 */
static int
init_device(ig_device_t *device, char *path)
{
        struct dk_gpt *vtoc;
        fstyp_handle_t fhdl;
        const char *fident;

        bzero(device, sizeof (*device));
        device->part_fd = -1;
        device->disk_fd = -1;
        device->path_p0 = NULL;

        device->path = strdup(path);
        if (device->path == NULL) {
                perror(gettext("Memory allocation failed"));
                return (BC_ERROR);
        }

        if (strstr(device->path, "diskette")) {
                (void) fprintf(stderr, gettext("installing GRUB to a floppy "
                    "disk is no longer supported\n"));
                return (BC_ERROR);
        }

        /* Detect if the target device is a pcfs partition. */
        if (strstr(device->path, "p0:boot"))
                device->type = IG_DEV_X86BOOTPAR;

        if (get_disk_fd(device) != BC_SUCCESS)
                return (BC_ERROR);

        /* read in the device boot sector. */
        if (read(device->disk_fd, device->boot_sector, SECTOR_SIZE)
            != SECTOR_SIZE) {
                (void) fprintf(stderr, gettext("Error reading boot sector\n"));
                perror("read");
                return (BC_ERROR);
        }

        if (efi_alloc_and_read(device->disk_fd, &vtoc) >= 0) {
                device->type = IG_DEV_EFI;
                efi_free(vtoc);
        }

        if (get_raw_partition_fd(device) != BC_SUCCESS)
                return (BC_ERROR);

        if (is_efi(device->type)) {
                if (fstyp_init(device->part_fd, 0, NULL, &fhdl) != 0)
                        return (BC_ERROR);

                if (fstyp_ident(fhdl, "zfs", &fident) != 0) {
                        fstyp_fini(fhdl);
                        (void) fprintf(stderr, gettext("Booting of EFI labeled "
                            "disks is only supported with ZFS\n"));
                        return (BC_ERROR);
                }
                fstyp_fini(fhdl);
        }

        if (get_start_sector(device) != BC_SUCCESS)
                return (BC_ERROR);

        return (BC_SUCCESS);
}

static void
cleanup_device(ig_device_t *device)
{
        if (device->path)
                free(device->path);
        if (device->path_p0)
                free(device->path_p0);

        if (device->part_fd != -1)
                (void) close(device->part_fd);
        if (device->disk_fd != -1)
                (void) close(device->disk_fd);

        bzero(device, sizeof (ig_device_t));
        device->part_fd = -1;
        device->disk_fd = -1;
}

static void
cleanup_stage2(ig_stage2_t *stage2)
{
        if (stage2->buf)
                free(stage2->buf);
        bzero(stage2, sizeof (ig_stage2_t));
}

static int
get_start_sector(ig_device_t *device)
{
        uint32_t                secnum = 0, numsec = 0;
        int                     i, pno, rval, log_part = 0;
        struct mboot            *mboot;
        struct ipart            *part = NULL;
        ext_part_t              *epp;
        struct part_info        dkpi;
        struct extpart_info     edkpi;

        if (is_efi(device->type)) {
                struct dk_gpt *vtoc;

                if (efi_alloc_and_read(device->disk_fd, &vtoc) < 0)
                        return (BC_ERROR);

                device->start_sector = vtoc->efi_parts[device->slice].p_start;
                /* GPT doesn't use traditional slice letters */
                device->partition = device->slice;
                device->slice = 0xff;

                efi_free(vtoc);
                goto found_part;
        }

        mboot = (struct mboot *)device->boot_sector;

        if (is_bootpar(device->type)) {
                if (find_x86_bootpar(mboot, &pno, &secnum) != BC_SUCCESS) {
                        (void) fprintf(stderr, NOBOOTPAR);
                        return (BC_ERROR);
                } else {
                        device->start_sector = secnum;
                        device->partition = pno;
                        goto found_part;
                }
        }

        /*
         * Search for Solaris fdisk partition
         * Get the solaris partition information from the device
         * and compare the offset of S2 with offset of solaris partition
         * from fdisk partition table.
         */
        if (ioctl(device->part_fd, DKIOCEXTPARTINFO, &edkpi) < 0) {
                if (ioctl(device->part_fd, DKIOCPARTINFO, &dkpi) < 0) {
                        (void) fprintf(stderr, PART_FAIL);
                        return (BC_ERROR);
                } else {
                        edkpi.p_start = dkpi.p_start;
                }
        }

        for (i = 0; i < FD_NUMPART; i++) {
                part = (struct ipart *)mboot->parts + i;

                if (part->relsect == 0) {
                        (void) fprintf(stderr, BAD_PART, i);
                        return (BC_ERROR);
                }

                if (edkpi.p_start >= part->relsect &&
                    edkpi.p_start < (part->relsect + part->numsect)) {
                        /* Found the partition */
                        break;
                }
        }

        if (i == FD_NUMPART) {
                /* No solaris fdisk partitions (primary or logical) */
                (void) fprintf(stderr, NOSOLPAR);
                return (BC_ERROR);
        }

        /*
         * We have found a Solaris fdisk partition (primary or extended)
         * Handle the simple case first: Solaris in a primary partition
         */
        if (!fdisk_is_dos_extended(part->systid)) {
                device->start_sector = part->relsect;
                device->partition = i;
                goto found_part;
        }

        /*
         * Solaris in a logical partition. Find that partition in the
         * extended part.
         */
        if ((rval = libfdisk_init(&epp, device->path_p0, NULL, FDISK_READ_DISK))
            != FDISK_SUCCESS) {
                switch (rval) {
                        /*
                         * The first 3 cases are not an error per-se, just that
                         * there is no Solaris logical partition
                         */
                        case FDISK_EBADLOGDRIVE:
                        case FDISK_ENOLOGDRIVE:
                        case FDISK_EBADMAGIC:
                                (void) fprintf(stderr, NOSOLPAR);
                                return (BC_ERROR);
                        case FDISK_ENOVGEOM:
                                (void) fprintf(stderr, NO_VIRT_GEOM);
                                return (BC_ERROR);
                        case FDISK_ENOPGEOM:
                                (void) fprintf(stderr, NO_PHYS_GEOM);
                                return (BC_ERROR);
                        case FDISK_ENOLGEOM:
                                (void) fprintf(stderr, NO_LABEL_GEOM);
                                return (BC_ERROR);
                        default:
                                (void) fprintf(stderr, LIBFDISK_INIT_FAIL);
                                return (BC_ERROR);
                }
        }

        rval = fdisk_get_solaris_part(epp, &pno, &secnum, &numsec);
        libfdisk_fini(&epp);
        if (rval != FDISK_SUCCESS) {
                /* No solaris logical partition */
                (void) fprintf(stderr, NOSOLPAR);
                return (BC_ERROR);
        }

        device->start_sector = secnum;
        device->partition = pno - 1;
        log_part = 1;

found_part:
        /* get confirmation for -m */
        if (write_mbr && !force_mbr) {
                (void) fprintf(stdout, MBOOT_PROMPT);
                if (!yes()) {
                        write_mbr = 0;
                        (void) fprintf(stdout, MBOOT_NOT_UPDATED);
                        return (BC_ERROR);
                }
        }

        /*
         * Currently if Solaris is in an extended partition we need to
         * write GRUB to the MBR. Check for this.
         */
        if (log_part && !write_mbr) {
                (void) fprintf(stdout, gettext("Installing Solaris on an "
                    "extended partition... forcing MBR update\n"));
                write_mbr = 1;
        }

        /*
         * warn, if Solaris in primary partition and GRUB not in MBR and
         * partition is not active
         */
        if (part != NULL) {
                if (!log_part && part->bootid != 128 && !write_mbr) {
                        (void) fprintf(stdout, SOLPAR_INACTIVE,
                            device->partition + 1);
                }
        }

        return (BC_SUCCESS);
}

static int
get_disk_fd(ig_device_t *device)
{
        int     i = 0;
        char    save[2] = { '\0', '\0' };
        char    *end = NULL;

        assert(device != NULL);
        assert(device->path != NULL);

        if (is_bootpar(device->type)) {
                end = strstr(device->path, "p0:boot");
                /* tested at the start of init_device() */
                assert(end != NULL);
                /* chop off :boot */
                save[0] = end[2];
                end[2] = '\0';
        } else {
                i = strlen(device->path);
                save[0] = device->path[i - 2];
                save[1] = device->path[i - 1];
                device->path[i - 2] = 'p';
                device->path[i - 1] = '0';
        }

        if (nowrite)
                device->disk_fd = open(device->path, O_RDONLY);
        else
                device->disk_fd = open(device->path, O_RDWR);

        device->path_p0 = strdup(device->path);
        if (device->path_p0 == NULL) {
                perror("strdup");
                return (BC_ERROR);
        }

        if (is_bootpar(device->type)) {
                end[2] = save[0];
        } else {
                device->path[i - 2] = save[0];
                device->path[i - 1] = save[1];
        }

        if (device->disk_fd == -1) {
                perror("open");
                return (BC_ERROR);
        }

        return (BC_SUCCESS);
}

static void
prepare_fake_multiboot(ig_stage2_t *stage2)
{
        multiboot_header_t      *mboot;

        assert(stage2 != NULL);
        assert(stage2->mboot != NULL);
        assert(stage2->buf != NULL);

        mboot = stage2->mboot;

        /*
         * Currently we expect find_multiboot() to have located a multiboot
         * header with the AOUT kludge flag set.
         */
        assert(mboot->flags & BB_MBOOT_AOUT_FLAG);

        /* Insert the information necessary to locate stage2. */
        mboot->header_addr = stage2->mboot_off;
        mboot->load_addr = 0;
        mboot->load_end_addr = stage2->file_size;
}

static void
add_stage2_einfo(ig_stage2_t *stage2, char *updt_str)
{
        bblk_hs_t       hs;
        uint32_t        avail_space;

        assert(stage2 != NULL);

        /* Fill bootblock hashing source information. */
        hs.src_buf = (unsigned char *)stage2->file;
        hs.src_size = stage2->file_size;
        /* How much space for the extended information structure? */
        avail_space = stage2->buf_size - P2ROUNDUP(stage2->file_size, 8);
        add_einfo(stage2->extra, updt_str, &hs, avail_space);
}


static int
write_stage2(ig_data_t *install)
{
        ig_device_t             *device = &install->device;
        ig_stage2_t             *stage2 = &install->stage2;
        off_t                   offset;

        assert(install != NULL);

        if (is_bootpar(device->type)) {
                /*
                 * stage2 is already on the filesystem, we only need to update
                 * the first two blocks (that we have modified during
                 * prepare_stage2())
                 */
                if (write_out(device->part_fd, stage2->file, SECTOR_SIZE,
                    stage2->pcfs_first_sectors[0] * SECTOR_SIZE)
                    != BC_SUCCESS ||
                    write_out(device->part_fd, stage2->file + SECTOR_SIZE,
                    SECTOR_SIZE, stage2->pcfs_first_sectors[1] * SECTOR_SIZE)
                    != BC_SUCCESS) {
                        (void) fprintf(stderr, WRITE_FAIL_STAGE2);
                        return (BC_ERROR);
                }
                (void) fprintf(stdout, WRITE_STAGE2_PCFS);
                return (BC_SUCCESS);
        }

        /*
         * For disk, write stage2 starting at STAGE2_BLKOFF sector.
         * Note that we use stage2->buf rather than stage2->file, because we
         * may have extended information after the latter.
         *
         * If we're writing to an EFI-labeled disk where stage2 lives in the
         * 3.5MB boot loader gap following the ZFS vdev labels, make sure the
         * size of the buffer doesn't exceed the size of the gap.
         */
        if (is_efi(device->type) && stage2->buf_size > STAGE2_MAXSIZE) {
                (void) fprintf(stderr, WRITE_FAIL_STAGE2);
                return (BC_ERROR);
        }

        offset = STAGE2_BLKOFF(device->type) * SECTOR_SIZE;

        if (write_out(device->part_fd, stage2->buf, stage2->buf_size,
            offset) != BC_SUCCESS) {
                perror("write");
                return (BC_ERROR);
        }

        /* Simulate the "old" installgrub output. */
        (void) fprintf(stdout, WRITE_STAGE2_DISK, device->partition,
            (stage2->buf_size / SECTOR_SIZE) + 1, STAGE2_BLKOFF(device->type),
            stage2->first_sector);

        return (BC_SUCCESS);
}

static int
write_stage1(ig_data_t *install)
{
        ig_device_t     *device = &install->device;

        assert(install != NULL);

        if (write_out(device->part_fd, install->stage1_buf,
            sizeof (install->stage1_buf), 0) != BC_SUCCESS) {
                (void) fprintf(stdout, WRITE_FAIL_PBOOT);
                perror("write");
                return (BC_ERROR);
        }

        /* Simulate "old" installgrub output. */
        (void) fprintf(stdout, WRITE_PBOOT, device->partition,
            device->start_sector);

        if (write_mbr) {
                if (write_out(device->disk_fd, install->stage1_buf,
                    sizeof (install->stage1_buf), 0) != BC_SUCCESS) {
                        (void) fprintf(stdout, WRITE_FAIL_BOOTSEC);
                        perror("write");
                        return (BC_ERROR);
                }
                /* Simulate "old" installgrub output. */
                (void) fprintf(stdout, WRITE_MBOOT);
        }

        return (BC_SUCCESS);
}

#define USAGE_STRING    "%s [-m|-f|-n|-F|-u verstr] stage1 stage2 device\n"    \
                        "%s -M [-n] device1 device2\n"                         \
                        "%s [-V|-e] -i device\n"                               \

#define CANON_USAGE_STR gettext(USAGE_STRING)

static void
usage(char *progname)
{
        (void) fprintf(stdout, CANON_USAGE_STR, progname, progname, progname);
}


static int
read_stage1_from_file(char *path, ig_data_t *dest)
{
        int     fd;

        assert(dest);

        /* read the stage1 file from filesystem */
        fd = open(path, O_RDONLY);
        if (fd == -1 ||
            read(fd, dest->stage1_buf, SECTOR_SIZE) != SECTOR_SIZE) {
                (void) fprintf(stderr, READ_FAIL_STAGE1, path);
                return (BC_ERROR);
        }
        (void) close(fd);
        return (BC_SUCCESS);
}

static int
read_stage2_from_file(char *path, ig_data_t *dest)
{
        int             fd;
        struct stat     sb;
        ig_stage2_t     *stage2 = &dest->stage2;
        ig_device_t     *device = &dest->device;
        uint32_t        buf_size;

        assert(dest);
        assert(stage2->buf == NULL);

        fd = open(path, O_RDONLY);
        if (fstat(fd, &sb) == -1) {
                perror("fstat");
                goto out;
        }

        stage2->file_size = sb.st_size;

        if (!is_bootpar(device->type)) {
                /*
                 * buffer size needs to account for stage2 plus the extra
                 * versioning information at the end of it. We reserve one
                 * extra sector (plus we round up to the next sector boundary).
                 */
                buf_size = stage2->file_size + SECTOR_SIZE;
        } else {
                /* In the PCFS case we only need to read in stage2. */
                buf_size = stage2->file_size;
        }

        stage2->buf_size = P2ROUNDUP(buf_size, SECTOR_SIZE);

        BOOT_DEBUG("stage2 buffer size = %d (%d sectors)\n", stage2->buf_size,
            stage2->buf_size / SECTOR_SIZE);

        stage2->buf = malloc(stage2->buf_size);
        if (stage2->buf == NULL) {
                perror(gettext("Memory allocation failed"));
                goto out_fd;
        }

        stage2->file = stage2->buf;

        /*
         * Extra information (e.g. the versioning structure) is placed at the
         * end of stage2, aligned on a 8-byte boundary.
         */
        if (!(is_bootpar(device->type)))
                stage2->extra = stage2->file + P2ROUNDUP(stage2->file_size, 8);

        if (lseek(fd, 0, SEEK_SET) == -1) {
                perror("lseek");
                goto out_alloc;
        }

        if (read(fd, stage2->file, stage2->file_size) < 0) {
                perror(gettext("unable to read stage2"));
                goto out_alloc;
        }

        (void) close(fd);
        return (BC_SUCCESS);

out_alloc:
        free(stage2->buf);
        stage2->buf = NULL;
out_fd:
        (void) close(fd);
out:
        return (BC_ERROR);
}

static int
prepare_stage1(ig_data_t *install)
{
        ig_device_t     *device = &install->device;

        assert(install != NULL);

        /* If PCFS add the BIOS Parameter Block. */
        if (is_bootpar(device->type)) {
                char    bpb_sect[SECTOR_SIZE];

                if (pread(device->part_fd, bpb_sect, SECTOR_SIZE, 0)
                    != SECTOR_SIZE) {
                        (void) fprintf(stderr, READ_FAIL_BPB);
                        return (BC_ERROR);
                }
                bcopy(bpb_sect + STAGE1_BPB_OFFSET,
                    install->stage1_buf + STAGE1_BPB_OFFSET, STAGE1_BPB_SIZE);
        }

        /* copy MBR to stage1 in case of overwriting MBR sector. */
        bcopy(device->boot_sector + BOOTSZ, install->stage1_buf + BOOTSZ,
            SECTOR_SIZE - BOOTSZ);
        /* modify default stage1 file generated by GRUB. */
        *((unsigned char *)(install->stage1_buf + STAGE1_FORCE_LBA)) = 1;
        *((ulong_t *)(install->stage1_buf + STAGE1_STAGE2_SECTOR))
            = install->stage2.first_sector;
        *((ushort_t *)(install->stage1_buf + STAGE1_STAGE2_ADDRESS))
            = STAGE2_MEMADDR;
        *((ushort_t *)(install->stage1_buf + STAGE1_STAGE2_SEGMENT))
            = STAGE2_MEMADDR >> 4;

        return (BC_SUCCESS);
}

/*
 * Grab stage1 from the specified device file descriptor.
 */
static int
read_stage1_from_disk(int dev_fd, char *stage1_buf)
{
        assert(stage1_buf != NULL);

        if (read_in(dev_fd, stage1_buf, SECTOR_SIZE, 0) != BC_SUCCESS) {
                perror(gettext("Unable to read stage1 from disk"));
                return (BC_ERROR);
        }
        return (BC_SUCCESS);
}

static int
read_stage2_from_disk(int dev_fd, ig_stage2_t *stage2, int type)
{
        uint32_t                size;
        uint32_t                buf_size;
        uint32_t                mboot_off;
        multiboot_header_t      *mboot;

        assert(stage2 != NULL);
        assert(dev_fd != -1);

        if (read_in(dev_fd, mboot_scan, sizeof (mboot_scan),
            STAGE2_BLKOFF(type) * SECTOR_SIZE) != BC_SUCCESS) {
                perror(gettext("Error reading stage2 sectors"));
                return (BC_ERROR);
        }

        /* No multiboot means no chance of knowing stage2 size */
        if (find_multiboot(mboot_scan, sizeof (mboot_scan), &mboot_off)
            != BC_SUCCESS) {
                BOOT_DEBUG("Unable to find multiboot header\n");
                return (BC_NOEXTRA);
        }
        mboot = (multiboot_header_t *)(mboot_scan + mboot_off);

        /*
         * Unfilled mboot values mean an older version of installgrub installed
         * the stage2. Again we have no chance of knowing stage2 size.
         */
        if (mboot->load_end_addr == 0 ||
            mboot->load_end_addr < mboot->load_addr)
                return (BC_NOEXTRA);

        /*
         * Currently, the amount of space reserved for extra information
         * is "fixed". We may have to scan for the terminating extra payload
         * in the future.
         */
        size = mboot->load_end_addr - mboot->load_addr;
        buf_size = P2ROUNDUP(size + SECTOR_SIZE, SECTOR_SIZE);

        stage2->buf = malloc(buf_size);
        if (stage2->buf == NULL) {
                perror(gettext("Memory allocation failed"));
                return (BC_ERROR);
        }
        stage2->buf_size = buf_size;

        if (read_in(dev_fd, stage2->buf, buf_size, STAGE2_BLKOFF(type) *
            SECTOR_SIZE) != BC_SUCCESS) {
                perror("read");
                free(stage2->buf);
                return (BC_ERROR);
        }

        /* Update pointers. */
        stage2->file = stage2->buf;
        stage2->file_size = size;
        stage2->mboot_off = mboot_off;
        stage2->mboot = (multiboot_header_t *)(stage2->buf + stage2->mboot_off);
        stage2->extra = stage2->buf + P2ROUNDUP(stage2->file_size, 8);
        stage2->extra_size = stage2->buf_size - P2ROUNDUP(stage2->file_size, 8);

        return (BC_SUCCESS);
}

static boolean_t
is_update_necessary(ig_data_t *data, char *updt_str)
{
        bblk_einfo_t    *einfo;
        bblk_hs_t       stage2_hs;
        ig_stage2_t     stage2_disk;
        ig_stage2_t     *stage2_file = &data->stage2;
        ig_device_t     *device = &data->device;
        int             dev_fd = device->part_fd;

        assert(data != NULL);
        assert(device->part_fd != -1);

        bzero(&stage2_disk, sizeof (ig_stage2_t));

        /* Gather stage2 (if present) from the target device. */
        if (read_stage2_from_disk(dev_fd, &stage2_disk, device->type)
            != BC_SUCCESS) {
                BOOT_DEBUG("Unable to read stage2 from %s\n", device->path);
                BOOT_DEBUG("No multiboot wrapped stage2 on %s\n", device->path);
                return (B_TRUE);
        }

        /*
         * Look for the extended information structure in the extra payload
         * area.
         */
        einfo = find_einfo(stage2_disk.extra, stage2_disk.extra_size);
        if (einfo == NULL) {
                BOOT_DEBUG("No extended information available\n");
                return (B_TRUE);
        }

        if (!do_version || updt_str == NULL) {
                (void) fprintf(stdout, "WARNING: target device %s has a "
                    "versioned stage2 that is going to be overwritten by a non "
                    "versioned one\n", device->path);
                return (B_TRUE);
        }

        if (force_update) {
                BOOT_DEBUG("Forcing update of %s bootblock\n", device->path);
                return (B_TRUE);
        }

        /* Compare the two extended information structures. */
        stage2_hs.src_buf = (unsigned char *)stage2_file->file;
        stage2_hs.src_size = stage2_file->file_size;

        return (einfo_should_update(einfo, &stage2_hs, updt_str));
}


#define START_BLOCK(pos)        (*(ulong_t *)(pos))
#define NUM_BLOCK(pos)          (*(ushort_t *)((pos) + 4))
#define START_SEG(pos)          (*(ushort_t *)((pos) + 6))

static int
prepare_stage2(ig_data_t *install, char *updt_str)
{
        ig_device_t     *device = &install->device;
        ig_stage2_t     *stage2 = &install->stage2;
        uint32_t        mboot_off = 0;

        assert(install != NULL);
        assert(stage2->file != NULL);

        /* New stage2 files come with an embedded stage2. */
        if (find_multiboot(stage2->file, stage2->file_size, &mboot_off)
            != BC_SUCCESS) {
                BOOT_DEBUG("WARNING: no multiboot structure found in stage2, "
                    "are you using an old GRUB stage2?\n");
                if (do_version == B_TRUE) {
                        (void) fprintf(stderr, gettext("Versioning requested "
                            "but stage2 does not support it.. skipping.\n"));
                        do_version = B_FALSE;
                }
        } else {
                /* Keep track of where the multiboot header is. */
                stage2->mboot_off = mboot_off;
                stage2->mboot = (multiboot_header_t *)(stage2->file +
                    mboot_off);
                if (do_version) {
                        /*
                         * Adding stage2 information needs to happen before
                         * we modify the copy of stage2 we have in memory, so
                         * that the hashing reflects the one of the file.
                         * An error here is not fatal.
                         */
                        add_stage2_einfo(stage2, updt_str);
                }
                /*
                 * Fill multiboot information. We add them even without
                 * versioning to support as much as possible mirroring.
                 */
                prepare_fake_multiboot(stage2);
        }

        if (is_bootpar(device->type)) {
                uint32_t        blocklist[SECTOR_SIZE / sizeof (uint32_t)];
                uint32_t        install_addr = STAGE2_MEMADDR + SECTOR_SIZE;
                int             i = 0;
                uchar_t         *pos;

                bzero(blocklist, sizeof (blocklist));
                if (read_stage2_blocklist(device->part_fd, blocklist) != 0) {
                        (void) fprintf(stderr, gettext("Error reading pcfs "
                            "stage2 blocklist\n"));
                        return (BC_ERROR);
                }

                pos = (uchar_t *)stage2->file + STAGE2_BLOCKLIST;
                stage2->first_sector = device->start_sector + blocklist[0];
                stage2->pcfs_first_sectors[0] = blocklist[0];
                BOOT_DEBUG("stage2 first sector: %d\n", stage2->first_sector);


                if (blocklist[1] > 1) {
                        blocklist[0]++;
                        blocklist[1]--;
                } else {
                        i += 2;
                }

                stage2->pcfs_first_sectors[1] = blocklist[i];

                while (blocklist[i]) {
                        if (START_BLOCK(pos - 8) != 0 &&
                            START_BLOCK(pos - 8) != blocklist[i + 2]) {
                                (void) fprintf(stderr, PCFS_FRAGMENTED);
                                return (BC_ERROR);
                        }
                        START_BLOCK(pos) = blocklist[i] + device->start_sector;
                        START_SEG(pos) = (ushort_t)(install_addr >> 4);
                        NUM_BLOCK(pos) = blocklist[i + 1];
                        install_addr += blocklist[i + 1] * SECTOR_SIZE;
                        pos -= 8;
                        i += 2;
                }
        } else {
                /* Solaris VTOC & EFI */
                if (device->start_sector >
                    UINT32_MAX - STAGE2_BLKOFF(device->type)) {
                        fprintf(stderr, gettext("Error: partition start sector "
                            "must be less than %lld\n"),
                            (uint64_t)UINT32_MAX - STAGE2_BLKOFF(device->type));
                        return (BC_ERROR);
                }
                stage2->first_sector = device->start_sector +
                    STAGE2_BLKOFF(device->type);
                BOOT_DEBUG("stage2 first sector: %d\n", stage2->first_sector);
                /*
                 * In a solaris partition, stage2 is written to contiguous
                 * blocks. So we update the starting block only.
                 */
                *((ulong_t *)(stage2->file + STAGE2_BLOCKLIST)) =
                    stage2->first_sector + 1;
        }

        /* force lba and set disk partition */
        *((unsigned char *) (stage2->file + STAGE2_FORCE_LBA)) = 1;
        *((long *)(stage2->file + STAGE2_INSTALLPART))
            = (device->partition << 16) | (device->slice << 8) | 0xff;

        return (BC_SUCCESS);
}

static int
find_x86_bootpar(struct mboot *mboot, int *part_num, uint32_t *start_sect)
{
        int     i;

        for (i = 0; i < FD_NUMPART; i++) {
                struct ipart    *part;

                part = (struct ipart *)mboot->parts + i;
                if (part->systid == 0xbe) {
                        if (start_sect)
                                *start_sect = part->relsect;
                        if (part_num)
                                *part_num = i;
                        /* solaris boot part */
                        return (BC_SUCCESS);
                }
        }
        return (BC_ERROR);
}

static char *
get_raw_partition_path(ig_device_t *device)
{
        char    *raw;
        int     len;

        if (is_bootpar(device->type)) {
                int             part;
                struct mboot    *mboot;

                mboot = (struct mboot *)device->boot_sector;
                if (find_x86_bootpar(mboot, &part, NULL) != BC_SUCCESS) {
                        (void) fprintf(stderr, BOOTPAR_NOTFOUND,
                            device->path_p0);
                        return (NULL);
                }

                raw = strdup(device->path_p0);
                if (raw == NULL) {
                        perror(gettext("Memory allocation failed"));
                        return (NULL);
                }

                raw[strlen(raw) - 2] = '1' + part;
                return (raw);
        }

        /* For disk, remember slice and return whole fdisk partition  */
        raw = strdup(device->path);
        if (raw == NULL) {
                perror(gettext("Memory allocation failed"));
                return (NULL);
        }

        len = strlen(raw);
        if (!is_efi(device->type) &&
            (raw[len - 2] != 's' || raw[len - 1] == '2')) {
                (void) fprintf(stderr, NOT_ROOT_SLICE);
                free(raw);
                return (NULL);
        }
        device->slice = atoi(&raw[len - 1]);

        if (!is_efi(device->type)) {
                raw[len - 2] = 's';
                raw[len - 1] = '2';
        }

        return (raw);
}

static int
get_raw_partition_fd(ig_device_t *device)
{
        struct stat     stat = {0};
        char            *raw;

        raw = get_raw_partition_path(device);
        if (raw == NULL)
                return (BC_ERROR);

        if (nowrite)
                device->part_fd = open(raw, O_RDONLY);
        else
                device->part_fd = open(raw, O_RDWR);

        if (device->part_fd < 0 || fstat(device->part_fd, &stat) != 0) {
                (void) fprintf(stderr, OPEN_FAIL, raw);
                free(raw);
                return (BC_ERROR);
        }

        if (S_ISCHR(stat.st_mode) == 0) {
                (void) fprintf(stderr, NOT_RAW_DEVICE, raw);
                (void) close(device->part_fd);
                device->part_fd = -1;
                free(raw);
                return (BC_ERROR);
        }

        free(raw);
        return (BC_SUCCESS);
}