grub/util/mkisofs/eltorito.c
Robert Millan e1f240ff44 2009-11-11 Robert Millan <rmh.grub@aybabtu.com>
Support for El Torito without floppy emulation.

        * util/mkisofs/eltorito.c: Include `<errno.h>'.
        (init_boot_catalog): Improve error handling.
        (get_torito_desc): Don't use floppy emulation unless requested by
        user. Patch boot information table when requested via
        `-boot-info-table'.
        * util/mkisofs/iso9660.h (struct eltorito_boot_info): New struct.
        * util/mkisofs/mkisofs.c (use_eltorito_emul_floppy)
        (use_boot_info_table): New variables.
        (OPTION_BOOT_INFO_TABLE, OPTION_NO_EMUL_BOOT)
        (OPTION_ELTORITO_EMUL_FLOPPY): New macros.
        (ld_options): Handle `-boot-info-table', `-no-emul-boot' and
        `--eltorito-emul-floppy'.
        (main): Handle `OPTION_BOOT_INFO_TABLE', `OPTION_NO_EMUL_BOOT'
        and `OPTION_ELTORITO_EMUL_FLOPPY'.
        * util/mkisofs/mkisofs.h (use_eltorito_emul_floppy)
        (use_boot_info_table, get_731): New prototypes.
        * util/mkisofs/write.c (get_731): New function.
2009-11-11 20:52:04 +00:00

343 lines
9.3 KiB
C

/*
* Program eltorito.c - Handle El Torito specific extensions to iso9660.
*
Written by Michael Fulbright <msf@redhat.com> (1996).
Copyright 1996 RedHat Software, Incorporated
Copyright (C) 2009 Free Software Foundation, Inc.
Boot Info Table generation based on code from genisoimage.c
(from cdrkit 1.1.9), which was originally licensed under GPLv2+.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>.
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
static char rcsid[] ="$Id: eltorito.c,v 1.13 1999/03/02 03:41:25 eric Exp $";
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <errno.h>
#include "config.h"
#include "mkisofs.h"
#include "iso9660.h"
/* used by Win32 for opening binary file - not used by Unix */
#ifndef O_BINARY
#define O_BINARY 0
#endif /* O_BINARY */
#undef MIN
#define MIN(a, b) (((a) < (b))? (a): (b))
static struct eltorito_validation_entry valid_desc;
static struct eltorito_defaultboot_entry default_desc;
static struct eltorito_boot_descriptor gboot_desc;
static int tvd_write __PR((FILE * outfile));
/*
* Check for presence of boot catalog. If it does not exist then make it
*/
void FDECL1(init_boot_catalog, const char *, path)
{
int bcat;
char * bootpath; /* filename of boot catalog */
char * buf;
struct stat statbuf;
bootpath = (char *) e_malloc(strlen(boot_catalog)+strlen(path)+2);
strcpy(bootpath, path);
if (bootpath[strlen(bootpath)-1] != '/')
{
strcat(bootpath,"/");
}
strcat(bootpath, boot_catalog);
/*
* check for the file existing
*/
#ifdef DEBUG_TORITO
fprintf(stderr,"Looking for boot catalog file %s\n",bootpath);
#endif
if (!stat_filter(bootpath, &statbuf))
{
/*
* make sure its big enough to hold what we want
*/
if (statbuf.st_size == 2048)
{
/*
* printf("Boot catalog exists, so we do nothing\n");
*/
free(bootpath);
return;
}
else
{
fprintf(stderr, "A boot catalog exists and appears corrupted.\n");
fprintf(stderr, "Please check the following file: %s.\n",bootpath);
fprintf(stderr, "This file must be removed before a bootable CD can be done.\n");
free(bootpath);
exit(1);
}
}
/*
* file does not exist, so we create it
* make it one CD sector long
*/
bcat = open(bootpath, O_WRONLY | O_CREAT | O_BINARY, S_IROTH | S_IRGRP | S_IRWXU );
if (bcat == -1)
error (1, errno, "Error creating boot catalog (%s)", bootpath);
buf = (char *) e_malloc( 2048 );
write(bcat, buf, 2048);
close(bcat);
free(bootpath);
} /* init_boot_catalog(... */
void FDECL1(get_torito_desc, struct eltorito_boot_descriptor *, boot_desc)
{
int bootcat;
int checksum;
unsigned char * checksum_ptr;
struct directory_entry * de;
struct directory_entry * de2;
unsigned int i;
int nsectors;
memset(boot_desc, 0, sizeof(*boot_desc));
boot_desc->id[0] = 0;
memcpy(boot_desc->id2, ISO_STANDARD_ID, sizeof(ISO_STANDARD_ID));
boot_desc->version[0] = 1;
memcpy(boot_desc->system_id, EL_TORITO_ID, sizeof(EL_TORITO_ID));
/*
* search from root of iso fs to find boot catalog
*/
de2 = search_tree_file(root, boot_catalog);
if (!de2)
{
fprintf(stderr,"Uh oh, I cant find the boot catalog!\n");
exit(1);
}
set_731(boot_desc->bootcat_ptr,
(unsigned int) get_733(de2->isorec.extent));
/*
* now adjust boot catalog
* lets find boot image first
*/
de=search_tree_file(root, boot_image);
if (!de)
{
fprintf(stderr,"Uh oh, I cant find the boot image!\n");
exit(1);
}
/*
* we have the boot image, so write boot catalog information
* Next we write out the primary descriptor for the disc
*/
memset(&valid_desc, 0, sizeof(valid_desc));
valid_desc.headerid[0] = 1;
valid_desc.arch[0] = EL_TORITO_ARCH_x86;
/*
* we'll shove start of publisher id into id field, may get truncated
* but who really reads this stuff!
*/
if (publisher)
memcpy_max(valid_desc.id, publisher, MIN(23, strlen(publisher)));
valid_desc.key1[0] = 0x55;
valid_desc.key2[0] = 0xAA;
/*
* compute the checksum
*/
checksum=0;
checksum_ptr = (unsigned char *) &valid_desc;
for (i=0; i<sizeof(valid_desc); i+=2)
{
/*
* skip adding in ckecksum word, since we dont have it yet!
*/
if (i == 28)
{
continue;
}
checksum += (unsigned int)checksum_ptr[i];
checksum += ((unsigned int)checksum_ptr[i+1])*256;
}
/*
* now find out the real checksum
*/
checksum = -checksum;
set_721(valid_desc.cksum, (unsigned int) checksum);
/*
* now make the initial/default entry for boot catalog
*/
memset(&default_desc, 0, sizeof(default_desc));
default_desc.boot_id[0] = EL_TORITO_BOOTABLE;
/*
* use default BIOS loadpnt
*/
set_721(default_desc.loadseg, 0);
default_desc.arch[0] = EL_TORITO_ARCH_x86;
/*
* figure out size of boot image in sectors, for now hard code to
* assume 512 bytes/sector on a bootable floppy
*/
nsectors = ((de->size + 511) & ~(511))/512;
fprintf(stderr, "\nSize of boot image is %d sectors -> ", nsectors);
if (! use_eltorito_emul_floppy)
{
default_desc.boot_media[0] = EL_TORITO_MEDIA_NOEMUL;
fprintf (stderr, "No emulation\n");
}
else if (nsectors == 2880 )
/*
* choose size of emulated floppy based on boot image size
*/
{
default_desc.boot_media[0] = EL_TORITO_MEDIA_144FLOP;
fprintf(stderr, "Emulating a 1.44 meg floppy\n");
}
else if (nsectors == 5760 )
{
default_desc.boot_media[0] = EL_TORITO_MEDIA_288FLOP;
fprintf(stderr,"Emulating a 2.88 meg floppy\n");
}
else if (nsectors == 2400 )
{
default_desc.boot_media[0] = EL_TORITO_MEDIA_12FLOP;
fprintf(stderr,"Emulating a 1.2 meg floppy\n");
}
else
{
fprintf(stderr,"\nError - boot image is not the an allowable size.\n");
exit(1);
}
/*
* FOR NOW LOAD 1 SECTOR, JUST LIKE FLOPPY BOOT!!!
*/
nsectors = 1;
set_721(default_desc.nsect, (unsigned int) nsectors );
#ifdef DEBUG_TORITO
fprintf(stderr,"Extent of boot images is %d\n",get_733(de->isorec.extent));
#endif
set_731(default_desc.bootoff,
(unsigned int) get_733(de->isorec.extent));
/*
* now write it to disk
*/
bootcat = open(de2->whole_name, O_RDWR | O_BINARY);
if (bootcat == -1)
{
fprintf(stderr,"Error opening boot catalog for update.\n");
perror("");
exit(1);
}
/*
* write out
*/
write(bootcat, &valid_desc, 32);
write(bootcat, &default_desc, 32);
close(bootcat);
/* If the user has asked for it, patch the boot image */
if (use_boot_info_table)
{
int bootimage;
uint32_t bi_checksum;
unsigned int total_len;
static char csum_buffer[SECTOR_SIZE];
int len;
struct eltorito_boot_info bi_table;
bootimage = open (de->whole_name, O_RDWR | O_BINARY);
if (bootimage == -1)
error (1, errno, "Error opening boot image file '%s' for update",
de->whole_name);
/* Compute checksum of boot image, sans 64 bytes */
total_len = 0;
bi_checksum = 0;
while ((len = read (bootimage, csum_buffer, SECTOR_SIZE)) > 0)
{
if (total_len & 3)
error (1, 0, "Odd alignment at non-end-of-file in boot image '%s'",
de->whole_name);
if (total_len < 64)
memset (csum_buffer, 0, 64 - total_len);
if (len < SECTOR_SIZE)
memset (csum_buffer + len, 0, SECTOR_SIZE - len);
for (i = 0; i < SECTOR_SIZE; i += 4)
bi_checksum += get_731 (&csum_buffer[i]);
total_len += len;
}
if (total_len != de->size)
error (1, 0, "Boot image file '%s' changed underneath us",
de->whole_name);
/* End of file, set position to byte 8 */
lseek (bootimage, (off_t) 8, SEEK_SET);
memset (&bi_table, 0, sizeof (bi_table));
/* Is it always safe to assume PVD is at session_start+16? */
set_731 (bi_table.pvd_addr, session_start + 16);
set_731 (bi_table.file_addr, de->starting_block);
set_731 (bi_table.file_length, de->size);
set_731 (bi_table.file_checksum, bi_checksum);
write (bootimage, &bi_table, sizeof (bi_table)); /* FIXME: check return value */
close (bootimage);
}
} /* get_torito_desc(... */
/*
* Function to write the EVD for the disc.
*/
static int FDECL1(tvd_write, FILE *, outfile)
{
/*
* Next we write out the boot volume descriptor for the disc
*/
get_torito_desc(&gboot_desc);
xfwrite(&gboot_desc, 1, 2048, outfile);
last_extent_written ++;
return 0;
}
struct output_fragment torito_desc = {NULL, oneblock_size, NULL, tvd_write};