NetBSD/sys/compat/freebsd/freebsd_exec_elf32.c
dsl b8fbaf8c4b Change the way that emulations locate files within the emulation root to
avoid having to allocate space in the 'stackgap'
  - which is very LWP unfriendly.
The additional code for non-emulation namei() is trivial, the reduction for
  the emulations is massive.
The vnode for a processes emulation root is saved in the cwdi structure
  during process exec.
If the emulation root the TRYEMULROOT flag are set, namei() will do an initial
  search for absolute pathnames in the emulation root, if that fails it will
  retry from the normal root.
".." at the emulation root will always go to the real root, even in the middle
  of paths and when expanding symlinks.
Absolute symlinks found using absolute paths in the emulation root will be
  relative to the emulation root (so /usr/lib/xxx.so -> /lib/xxx.so links
  inside the emulation root don't need changing).
If the root of the emulation would be returned (for an emulation lookup), then
  the real root is returned instead (matching the behaviour of emul_lookup,
  but being a cheap comparison here) so that programs that scan "../.."
  looking for the root dircetory don't loop forever.
The target for symbolic links is no longer mangled (it used to get the
  CHECK_ALT_xxx() treatment, so could get /emul/xxx prepended).
CHECK_ALT_xxx() are no more. Most of the change is deleting them, and adding
  TRYEMULROOT to the flags to NDINIT().
A lot of the emulation system call stubs could now be deleted.
2007-04-22 08:29:55 +00:00

137 lines
4.0 KiB
C

/* $NetBSD: freebsd_exec_elf32.c,v 1.17 2007/04/22 08:29:56 dsl Exp $ */
/*
* Copyright (c) 1993, 1994 Christopher G. Demetriou
* 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 Christopher G. Demetriou.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: freebsd_exec_elf32.c,v 1.17 2007/04/22 08:29:56 dsl Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/exec.h>
#ifndef ELFSIZE
# define ELFSIZE 32
#endif /* !ELFSIZE */
#include <sys/exec_elf.h>
#include <compat/sys/signal.h>
#include <compat/sys/signalvar.h>
#include <compat/freebsd/freebsd_exec.h>
#include <compat/common/compat_util.h>
#include <machine/freebsd_machdep.h>
int
ELFNAME2(freebsd,probe)(
struct lwp *l,
struct exec_package *epp,
void *veh,
char *itp,
vaddr_t *pos)
{
int error;
size_t i;
size_t phsize;
Elf_Ehdr *eh = (Elf_Ehdr *) veh;
Elf_Phdr *ph;
Elf_Phdr *ephp;
Elf_Nhdr *np;
static const char wantBrand[] = FREEBSD_ELF_BRAND_STRING;
static const char wantInterp[] = FREEBSD_ELF_INTERP_PREFIX_STRING;
/*
* Insist that the executable have a brand, and that it be "FreeBSD".
* Newer FreeBSD binaries have OSABI set to ELFOSABI_FREEBSD. This
* is arguably broken, but they seem to think they need it, for
* whatever reason.
*/
#ifndef EI_BRAND
#define EI_BRAND 8
#endif
if ((eh->e_ident[EI_BRAND] == '\0'
|| strcmp(&eh->e_ident[EI_BRAND], wantBrand) != 0)
&& eh->e_ident[EI_OSABI] != ELFOSABI_FREEBSD)
return ENOEXEC;
i = eh->e_phnum;
if (i != 0) {
phsize = i * sizeof(Elf_Phdr);
ph = (Elf_Phdr *) malloc(phsize, M_TEMP, M_WAITOK);
if ((error = exec_read_from(l, epp->ep_vp, eh->e_phoff, ph,
phsize)) != 0)
goto bad1;
for (ephp = ph; i--; ephp++) {
if (ephp->p_type != PT_INTERP)
continue;
/* Check for "legal" intepreter name. */
if (ephp->p_filesz < sizeof wantInterp)
goto bad1;
np = (Elf_Nhdr *) malloc(ephp->p_filesz+1,
M_TEMP, M_WAITOK);
if (((error = exec_read_from(l, epp->ep_vp,
ephp->p_offset, np, ephp->p_filesz)) != 0))
goto bad2;
if (strncmp((char *)np, wantInterp,
sizeof wantInterp - 1))
goto bad2;
free(np, M_TEMP);
break;
}
free(ph, M_TEMP);
}
if (itp) {
if ((error = emul_find_interp(l, epp, itp)))
return error;
}
#ifdef DEBUG_FREEBSD_ELF
printf("freebsd_elf32_probe: returning 0\n");
#endif
return 0;
bad2:
free(np, M_TEMP);
bad1:
free(ph, M_TEMP);
return ENOEXEC;
}