/*
 * This file and its contents are supplied under the terms of the
 * Common Development and Distribution License ("CDDL"), version 1.0.
 * You may only use this file in accordance with the terms of version
 * 1.0 of the CDDL.
 *
 * A full copy of the text of the CDDL should have accompanied this
 * source.  A copy of the CDDL is also available via the Internet at
 * http://www.illumos.org/license/CDDL.
 */

/*
 * Copyright 2016 Toomas Soome <tsoome@me.com>
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/sysmacros.h>
#include <sys/multiboot.h>

#include "bblk_einfo.h"
#include "boot_utils.h"
#include "mboot_extra.h"

/*
 * Add version to loader bootblock file. The file should have fake
 * multiboot header and version data will be added at the end of the file.
 * MB header is fake in sense that this bootblock is *not* MB compatible,
 * and MB header will only include load_addr and load_end_addr components.
 * load_addr will be set to value 0 to indicate the beginning of the file
 * and load_end_addr will be set to the size of the original file.
 * The flags value in header must be exactly AOUT kludge.
 *
 * version data is aligned by 8 bytes and whole blootblock will be padded to
 * 512B sector size.
 *
 * To use and verify version data, first find MB header, then load_end_addr
 * will point to the end of the original file, aligned up by 8, is version
 * data implemented as bblk einfo.
 */

void
add_version(const char *ifile, const char *ofile, char *version)
{
        int fd;
        int ret;
        uint32_t buf_size;
        uint32_t mboot_off;
        uint32_t extra;
        uint32_t avail_space;
        multiboot_header_t *mboot;
        struct stat sb;
        char *buf;
        bblk_hs_t hs;

        fd = open(ifile, O_RDONLY);
        if (fd == -1) {
                perror("open");
                return;
        }
        if (fstat(fd, &sb) == -1) {
                perror("fstat");
                close(fd);
                return;
        }

        /*
         * make sure we have enough space to append EINFO.
         */
        buf_size = P2ROUNDUP(sb.st_size + SECTOR_SIZE, SECTOR_SIZE);
        buf = malloc(buf_size);
        if (buf == NULL) {
                perror("malloc");
                close(fd);
                return;
        }

        /*
         * read in whole file. we need to access MB header and einfo
         * will create MD5 hash.
         */
        ret = read(fd, buf, sb.st_size);
        if (ret != sb.st_size) {
                perror("read");
                free(buf);
                close(fd);
                return;
        }
        close(fd);

        if (find_multiboot(buf, MBOOT_SCAN_SIZE, &mboot_off)
            != BC_SUCCESS) {
                printf("Unable to find multiboot header\n");
                free(buf);
                return;
        }

        mboot = (multiboot_header_t *)(buf + mboot_off);
        mboot->load_addr = 0;
        mboot->load_end_addr = sb.st_size;


        hs.src_buf = (unsigned char *)buf;
        hs.src_size = sb.st_size;

        /*
         * this is location for EINFO data
         */
        extra = P2ROUNDUP(sb.st_size, 8);
        avail_space = buf_size - extra;
        memset(buf+sb.st_size, 0, buf_size - sb.st_size);
        add_einfo(buf + extra, version, &hs, avail_space);

        fd = open(ofile, O_CREAT | O_WRONLY | O_TRUNC, 0644);
        if (fd == -1) {
                perror("open");
                free(buf);
                return;
        }
        ret = write(fd, buf, buf_size);
        close(fd);
        free(buf);
}