tools/btxld/version.c

/*
 * 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(char *file, 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(file, 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(file, O_WRONLY | O_TRUNC);
    if (fd == -1) {
        perror("open");
        free(buf);
        return;
    }
    ret = write(fd, buf, buf_size);
    close(fd);
    free(buf);
}