mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-04 09:09:56 +00:00
203 lines
4.7 KiB
C
203 lines
4.7 KiB
C
/*
|
|
* Copyright (c) 1996 Whistle Communications
|
|
* All Rights Reserved.
|
|
*
|
|
* Permission to use, copy, modify and distribute this software and its
|
|
* documentation is hereby granted, provided that both the copyright
|
|
* notice and this permission notice appear in all copies of the
|
|
* software, derivative works or modified versions, and any portions
|
|
* thereof, and that both notices appear in supporting documentation.
|
|
*
|
|
* Whistle Communications allows free use of this software in its "as is"
|
|
* condition. Whistle Communications disclaims any liability of any kind for
|
|
* any damages whatsoever resulting from the use of this software.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static const char rcsid[] =
|
|
"$FreeBSD$";
|
|
#endif /* not lint */
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/disklabel.h>
|
|
#include <fcntl.h>
|
|
#include <err.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
struct mboot
|
|
{
|
|
unsigned char padding[2]; /* force the longs to be long aligned */
|
|
unsigned char bootinst[DOSPARTOFF];
|
|
struct dos_partition parts[4];
|
|
unsigned short int signature;
|
|
};
|
|
struct mboot mboot;
|
|
|
|
#define NAMEBLOCK 1 /* 2nd block */
|
|
#define BLOCKSIZE 512
|
|
#define ENABLE_MAGIC 0xfadefeed
|
|
#define DISABLE_MAGIC 0xfadefade
|
|
static int bflag;
|
|
static int eflag;
|
|
static int dflag;
|
|
|
|
#define BOOT_MAGIC 0xAA55
|
|
|
|
static void
|
|
usage(void) {
|
|
fprintf (stderr, "%s\n%s\n",
|
|
"usage: nextboot [-b] device bootstring [bootstring] ...",
|
|
" nextboot {-e,-d} device");
|
|
exit(1);
|
|
}
|
|
|
|
int
|
|
main (int argc, char** argv)
|
|
{
|
|
int fd = -1;
|
|
char namebuf[1024], *cp = namebuf;
|
|
int i,j;
|
|
int ch;
|
|
int part;
|
|
|
|
bflag = 0;
|
|
while ((ch = getopt(argc, argv, "bde")) != -1) {
|
|
switch(ch) {
|
|
case 'b':
|
|
bflag = 1;
|
|
break;
|
|
case 'd':
|
|
dflag = 1;
|
|
break;
|
|
case 'e':
|
|
eflag = 1;
|
|
break;
|
|
case '?':
|
|
default:
|
|
usage();
|
|
}
|
|
}
|
|
argc -= optind;
|
|
argv += optind;
|
|
|
|
if ( (dflag + eflag + bflag) > 1 ) {
|
|
usage();
|
|
}
|
|
if (dflag + eflag){
|
|
if(argc != 1 ) {
|
|
usage();
|
|
}
|
|
} else {
|
|
if (argc <2) {
|
|
usage();
|
|
}
|
|
}
|
|
if ((fd = open(argv[0], O_RDWR, 0)) < 0)
|
|
errx(1, "can't open %s", argv[0]);
|
|
|
|
argc--;
|
|
argv++;
|
|
|
|
/*******************************************
|
|
* Check that we have an MBR
|
|
*/
|
|
if (lseek(fd,0,0) == -1)
|
|
err(1, "lseek");
|
|
if (read (fd,&mboot.bootinst[0],BLOCKSIZE ) != BLOCKSIZE)
|
|
err(1, "read0");
|
|
if (mboot.signature != (unsigned short)BOOT_MAGIC)
|
|
errx(1, "no fdisk part.. not touching block 1");
|
|
|
|
/*******************************************
|
|
* And check that none of the partitions in it cover the name block;
|
|
*/
|
|
for ( part = 0; part < 4; part++) {
|
|
if( mboot.parts[part].dp_size
|
|
&& (mboot.parts[part].dp_start <= NAMEBLOCK)
|
|
&& (mboot.parts[part].dp_start
|
|
+ mboot.parts[part].dp_size > NAMEBLOCK))
|
|
errx(1,
|
|
"name sector lies within a Bios partition: aborting write");
|
|
}
|
|
|
|
|
|
/*******************************************
|
|
* Now check the name sector itself to see if it's been initialized.
|
|
*/
|
|
if (lseek(fd,NAMEBLOCK * BLOCKSIZE,0) == -1)
|
|
err(1, "lseek");
|
|
if (read(fd,namebuf,BLOCKSIZE) != BLOCKSIZE)
|
|
err(1, "read1");
|
|
/*******************************************
|
|
* check if we are just enabling or disabling
|
|
* Remember the flags are exclusive..
|
|
*/
|
|
if(!bflag) { /* don't care what's there if bflag is set */
|
|
switch(*(unsigned long *)cp)
|
|
{
|
|
case DISABLE_MAGIC:
|
|
case ENABLE_MAGIC:
|
|
break;
|
|
default:
|
|
errx(1, "namesector not initialized, use the -b flag");
|
|
}
|
|
}
|
|
|
|
|
|
/*******************************************
|
|
* If the z or r flag is set, damage or restore the magic number..
|
|
* to disable/enable the feature
|
|
*/
|
|
if(dflag) {
|
|
*(unsigned long *)cp = DISABLE_MAGIC;
|
|
} else {
|
|
*(unsigned long *)cp = ENABLE_MAGIC;
|
|
}
|
|
if ((!dflag) && (!eflag)) {
|
|
/*******************************************
|
|
* Create a new namesector in ram
|
|
*/
|
|
cp += 4;
|
|
for ( i = 0 ; i < argc ; i++ ) {
|
|
*cp++ = 'D';
|
|
*cp++ = 'N';
|
|
j = strlen(argv[i]);
|
|
strncpy(cp,argv[i],j);
|
|
cp += j;
|
|
*cp++ = 0;
|
|
}
|
|
*cp++ = 0xff;
|
|
*cp++ = 0xff;
|
|
*cp++ = 0xff;
|
|
namebuf[BLOCKSIZE-1] = 0; /* paranoid */
|
|
namebuf[BLOCKSIZE] = 0xff;
|
|
}
|
|
|
|
/*******************************************
|
|
* write it to disk.
|
|
*/
|
|
if (lseek(fd,NAMEBLOCK * BLOCKSIZE,0) == -1)
|
|
err(1, "lseek");
|
|
if(write (fd,namebuf,BLOCKSIZE ) != BLOCKSIZE)
|
|
err(1, "write");
|
|
|
|
#if 0
|
|
/*******************************************
|
|
* just to be safe/paranoid.. read it back..
|
|
* and print it..
|
|
*/
|
|
if (lseek(fd,NAMEBLOCK * BLOCKSIZE,0) == -1)
|
|
err(1, "lseek (second)");
|
|
read (fd,namebuf,512);
|
|
for (i = 0;i< 16;i++) {
|
|
for ( j = 0; j < 16; j++) {
|
|
printf("%02x ",(unsigned char )namebuf[(i*16) + j ]);
|
|
}
|
|
printf("\n");
|
|
}
|
|
#endif
|
|
exit(0);
|
|
}
|