NetBSD/sys/compat/linux/common/linux_exec_elf32.c

337 lines
8.9 KiB
C

/* $NetBSD: linux_exec_elf32.c,v 1.54 2001/11/13 02:08:51 lukem Exp $ */
/*-
* Copyright (c) 1995, 1998, 2000, 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas, Frank van der Linden, Eric Haszlakiewicz and
* Emmanuel Dreyfus.
*
* 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 NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* based on exec_aout.c, sunos_exec.c and svr4_exec.c
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: linux_exec_elf32.c,v 1.54 2001/11/13 02:08:51 lukem Exp $");
#ifndef ELFSIZE
#define ELFSIZE 32 /* XXX should die */
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/exec.h>
#include <sys/exec_elf.h>
#include <sys/mman.h>
#include <sys/syscallargs.h>
#include <machine/cpu.h>
#include <machine/reg.h>
#include <compat/linux/common/linux_types.h>
#include <compat/linux/common/linux_signal.h>
#include <compat/linux/common/linux_util.h>
#include <compat/linux/common/linux_exec.h>
#include <compat/linux/common/linux_machdep.h>
#include <compat/linux/linux_syscallargs.h>
#include <compat/linux/linux_syscall.h>
static int ELFNAME2(linux,signature) __P((struct proc *, struct exec_package *,
Elf_Ehdr *, char *));
#ifdef LINUX_GCC_SIGNATURE
static int ELFNAME2(linux,gcc_signature) __P((struct proc *p,
struct exec_package *, Elf_Ehdr *));
#endif
#ifdef LINUX_ATEXIT_SIGNATURE
static int ELFNAME2(linux,atexit_signature) __P((struct proc *p,
struct exec_package *, Elf_Ehdr *));
#endif
#ifdef LINUX_ATEXIT_SIGNATURE
/*
* On the PowerPC, statically linked Linux binaries are not recognized
* by linux_signature nor by linux_gcc_signature. Fortunately, thoses
* binaries features a __libc_atexit ELF section. We therefore assume we
* have a Linux binary if we find this section.
*/
static int
ELFNAME2(linux,atexit_signature)(p, epp, eh)
struct proc *p;
struct exec_package *epp;
Elf_Ehdr *eh;
{
size_t shsize;
int strndx;
size_t i;
static const char signature[] = "__libc_atexit";
char* strtable;
Elf_Shdr *sh;
int error;
/*
* load the section header table
*/
shsize = eh->e_shnum * sizeof(Elf_Shdr);
sh = (Elf_Shdr *) malloc(shsize, M_TEMP, M_WAITOK);
error = exec_read_from(p, epp->ep_vp, eh->e_shoff, sh, shsize);
if (error)
goto out;
/*
* Now let's find the string table. If it does not exists, give up.
*/
strndx = (int)(eh->e_shstrndx);
if (strndx == SHN_UNDEF) {
error = ENOEXEC;
goto out;
}
/*
* strndx is the index in section header table of the string table
* section get the whole string table in strtable, and then we get access to the names
* s->sh_name is the offset of the section name in strtable.
*/
strtable = malloc(sh[strndx].sh_size, M_TEMP, M_WAITOK);
error = exec_read_from(p, epp->ep_vp, sh[strndx].sh_offset, strtable,
sh[strndx].sh_size);
if (error)
goto out;
for (i = 0; i < eh->e_shnum; i++) {
Elf_Shdr *s = &sh[i];
if (!memcmp((void*)(&(strtable[s->sh_name])), signature,
sizeof(signature))) {
#ifdef DEBUG_LINUX
printf("linux_atexit_sig=%s\n",&(strtable[s->sh_name]));
#endif
error = 0;
goto out;
}
}
error = ENOEXEC;
out:
free(sh, M_TEMP);
free(strtable, M_TEMP);
return (error);
}
#endif
#ifdef LINUX_GCC_SIGNATURE
/*
* Take advantage of the fact that all the linux binaries are compiled
* with gcc, and gcc sticks in the comment field a signature. Note that
* on SVR4 binaries, the gcc signature will follow the OS name signature,
* that will not be a problem. We don't bother to read in the string table,
* but we check all the progbits headers.
*
* XXX This only works in the i386. On the alpha (at least)
* XXX we have the same gcc signature which incorrectly identifies
* XXX NetBSD binaries as Linux.
*/
static int
ELFNAME2(linux,gcc_signature)(p, epp, eh)
struct proc *p;
struct exec_package *epp;
Elf_Ehdr *eh;
{
size_t shsize;
size_t i;
static const char signature[] = "\0GCC: (GNU) ";
char buf[sizeof(signature) - 1];
Elf_Shdr *sh;
int error;
shsize = eh->e_shnum * sizeof(Elf_Shdr);
sh = (Elf_Shdr *) malloc(shsize, M_TEMP, M_WAITOK);
error = exec_read_from(p, epp->ep_vp, eh->e_shoff, sh, shsize);
if (error)
goto out;
for (i = 0; i < eh->e_shnum; i++) {
Elf_Shdr *s = &sh[i];
/*
* Identify candidates for the comment header;
* Header cannot have a load address, or flags and
* it must be large enough.
*/
if (s->sh_type != SHT_PROGBITS ||
s->sh_addr != 0 ||
s->sh_flags != 0 ||
s->sh_size < sizeof(signature) - 1)
continue;
error = exec_read_from(p, epp->ep_vp, s->sh_offset, buf,
sizeof(signature) - 1);
if (error)
continue;
/*
* error is 0, if the signatures match we are done.
*/
#ifdef DEBUG_LINUX
printf("linux_gcc_sig: sig=%s\n", buf);
#endif
if (!memcmp(buf, signature, sizeof(signature) - 1)) {
error = 0;
goto out;
}
}
error = ENOEXEC;
out:
free(sh, M_TEMP);
return (error);
}
#endif
static int
ELFNAME2(linux,signature)(p, epp, eh, itp)
struct proc *p;
struct exec_package *epp;
Elf_Ehdr *eh;
char *itp;
{
size_t i;
Elf_Phdr *ph;
size_t phsize;
int error;
phsize = eh->e_phnum * sizeof(Elf_Phdr);
ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
error = exec_read_from(p, epp->ep_vp, eh->e_phoff, ph, phsize);
if (error)
goto out;
for (i = 0; i < eh->e_phnum; i++) {
Elf_Phdr *ephp = &ph[i];
Elf_Nhdr *np;
u_int32_t *abi;
if (ephp->p_type != PT_NOTE ||
ephp->p_filesz > 1024 ||
ephp->p_filesz < sizeof(Elf_Nhdr) + 20)
continue;
np = (Elf_Nhdr *)malloc(ephp->p_filesz, M_TEMP, M_WAITOK);
error = exec_read_from(p, epp->ep_vp, ephp->p_offset, np,
ephp->p_filesz);
if (error)
goto next;
if (np->n_type != ELF_NOTE_TYPE_ABI_TAG ||
np->n_namesz != ELF_NOTE_ABI_NAMESZ ||
np->n_descsz != ELF_NOTE_ABI_DESCSZ ||
memcmp((caddr_t)(np + 1), ELF_NOTE_ABI_NAME,
ELF_NOTE_ABI_NAMESZ))
goto next;
/* Make sure the OS is Linux. */
abi = (u_int32_t *)((caddr_t)np + sizeof(Elf_Nhdr) +
np->n_namesz);
if (abi[0] == ELF_NOTE_ABI_OS_LINUX)
error = 0;
else
error = ENOEXEC;
free(np, M_TEMP);
goto out;
next:
free(np, M_TEMP);
continue;
}
/* Check for certain intepreter names. */
if (itp[0]) {
if (!strncmp(itp, "/lib/ld-linux", 13) ||
!strncmp(itp, "/lib/ld.so.", 11))
error = 0;
else
error = ENOEXEC;
goto out;
}
error = ENOEXEC;
out:
free(ph, M_TEMP);
return (error);
}
int
ELFNAME2(linux,probe)(p, epp, eh, itp, pos)
struct proc *p;
struct exec_package *epp;
void *eh;
char *itp;
vaddr_t *pos;
{
const char *bp;
int error;
size_t len;
if (((error = ELFNAME2(linux,signature)(p, epp, eh, itp)) != 0) &&
#ifdef LINUX_GCC_SIGNATURE
((error = ELFNAME2(linux,gcc_signature)(p, epp, eh)) != 0) &&
#endif
#ifdef LINUX_ATEXIT_SIGNATURE
((error = ELFNAME2(linux,atexit_signature)(p, epp, eh)) != 0) &&
#endif
1)
return error;
if (itp[0]) {
if ((error = emul_find(p, NULL, epp->ep_esch->es_emul->e_path,
itp, &bp, 0)))
return error;
if ((error = copystr(bp, itp, MAXPATHLEN, &len)))
return error;
free((void *)bp, M_TEMP);
}
*pos = ELF_NO_ADDR;
#ifdef DEBUG_LINUX
printf("linux_probe: returning 0\n");
#endif
return 0;
}