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/* $OpenBSD: exec.c,v 1.12 1997/03/30 20:13:04 mickey Exp $ */
/* $NetBSD: exec.c,v 1.15 1996/10/13 02:29:01 christos Exp $ */
/*-
* Copyright (c) 1982, 1986, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/exec.h>
#include <sys/reboot.h>
#ifndef INSECURE
#include <sys/stat.h>
#endif
#include "stand.h"
static char *ssym, *esym;
extern u_int opendev;
void
exec(path, loadaddr, howto)
char *path;
void *loadaddr;
int howto;
{
register int io;
#ifndef INSECURE
struct stat sb;
#endif
struct exec x;
int i;
register char *addr;
#ifdef EXEC_DEBUG
char *daddr, *etxt;
#endif
io = open(path, 0);
if (io < 0)
return;
#ifndef INSECURE
(void) fstat(io, &sb);
if (sb.st_uid || (sb.st_mode & 2)) {
printf("non-secure file, will not load\n");
close(io);
errno = EPERM;
return;
}
#endif
i = read(io, (char *)&x, sizeof(x));
if (i != sizeof(x) ||
N_BADMAG(x)) {
errno = EFTYPE;
return;
}
#ifdef EXEC_DEBUG
printf("\nstruct exec {%lx, %lx, %lx, %lx, %lx, %lx, %lx, %lx}\n",
x.a_midmag, x.a_text, x.a_data, x.a_bss, x.a_syms,
x.a_entry, x.a_trsize, x.a_drsize);
#endif
/* Text */
printf("%ld", x.a_text);
addr = loadaddr;
i = x.a_text;
if (N_GETMAGIC(x) == ZMAGIC) {
bcopy((char *)&x, addr, sizeof x);
addr += sizeof x;
i -= sizeof x;
}
if (read(io, (char *)addr, i) != i)
goto shread;
addr += i;
#ifdef EXEC_DEBUG
printf("\ntext {%x, %x, %x, %x}\n",
addr[0], addr[1], addr[2], addr[3]);
etxt = addr;
#endif
if (N_GETMAGIC(x) == NMAGIC)
while ((long)addr & (N_PAGSIZ(x) - 1))
*addr++ = 0;
/* Data */
#ifdef EXEC_DEBUG
daddr = addr;
#endif
printf("+%ld", x.a_data);
if (read(io, addr, x.a_data) != x.a_data)
goto shread;
addr += x.a_data;
/* Bss */
printf("+%ld", x.a_bss);
for (i = 0; i < x.a_bss; i++)
*addr++ = 0;
/* Symbols */
ssym = addr;
bcopy(&x.a_syms, addr, sizeof(x.a_syms));
addr += sizeof(x.a_syms);
printf("+[%ld", x.a_syms);
if (read(io, addr, x.a_syms) != x.a_syms)
goto shread;
addr += x.a_syms;
if (read(io, &i, sizeof(int)) != sizeof(int))
goto shread;
bcopy(&i, addr, sizeof(int));
if (i) {
i -= sizeof(int);
addr += sizeof(int);
if (read(io, addr, i) != i)
goto shread;
addr += i;
}
/* and that many bytes of string table */
printf("+%d]", i);
close(io);
#define round_to_size(x) \
(((int)(x) + sizeof(int) - 1) & ~(sizeof(int) - 1))
esym = (char *)round_to_size(addr - (char *)loadaddr);
#undef round_to_size
/* and note the end address of all this */
printf(" total=0x%lx", (u_long)addr);
/* XXX - Hack alert!
This is no good, loadaddr is passed into
machdep_start(), and it should do whatever
is needed.
x.a_entry += (long)loadaddr;
*/
printf(" start=0x%lx\n", x.a_entry);
#ifdef EXEC_DEBUG
printf("loadaddr=%p etxt=%p daddr=%p ssym=%p esym=%p\n",
loadaddr, etxt, daddr, ssym, esym);
printf("\n\nReturn to boot...\n");
getchar();
#endif
machdep_start((char *)x.a_entry, howto, loadaddr, ssym, esym);
/* exec failed */
errno = ENOEXEC;
return;
shread:
close(io);
errno = EIO;
return;
}
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