NetBSD/libexec/ld.elf_so/compat.c

95 lines
3.6 KiB
C

/* $NetBSD: compat.c,v 1.1 2018/10/17 23:36:58 joerg Exp $ */
/*-
* Copyright (c) 2018 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Joerg Sonnenberger.
*
* 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.
*
* 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.
*/
/*
* Early ELF support in NetBSD up to April 2nd, 2000 exposed dlopen and
* friends via function pointers in the main object that is passed to the
* startup code in crt0.o. Later versions kept the magic and version number
* checks, but depend on normal symbol interposition to get the symbols from
* rtld. The compatibility object build here contains just enough fields to
* make either routine happy without polluting the rest of rtld.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: compat.c,v 1.1 2018/10/17 23:36:58 joerg Exp $");
#include "rtld.h"
#if defined(__alpha__)
#define RTLD_OBJ_DLOPEN_OFFSET 264
#elif defined(__i386__)
#define RTLD_OBJ_DLOPEN_OFFSET 140
#elif defined(__mips) && defined(_ABIO32)
/* The MIPS legacy support is required for O32 only, N32 is not affected. */
#define RTLD_OBJ_DLOPEN_OFFSET 152
#elif defined(__powerpc__) && !defined(__powerpc64__)
/* Only 32bit PowerPC is affected. */
#define RTLD_OBJ_DLOPEN_OFFSET 140
#elif defined(__sparc) && !defined(__sparc64__)
/* Only 32bit SPARC is affected, 64bit SPARC ELF support was incomplete. */
#define RTLD_OBJ_DLOPEN_OFFSET 140
#endif
#define RTLD_MAGIC 0xd550b87a
#define RTLD_VERSION 1
#ifdef RTLD_OBJ_DLOPEN_OFFSET
const uintptr_t _rtld_compat_obj[] = {
# ifdef _LP64
# if BYTE_ORDER == BIG_ENDIAN
[0] = (((uint64_t)RTLD_MAGIC) << 32) | RTLD_VERSION,
# else
[0] = (((uint64_t)RTLD_VERSION) << 32) | RTLD_MAGIC,
# endif
# else
[0] = RTLD_MAGIC,
[1] = RTLD_VERSION,
# endif
[(RTLD_OBJ_DLOPEN_OFFSET / sizeof(uintptr_t)) + 0] = (uintptr_t)dlopen,
[(RTLD_OBJ_DLOPEN_OFFSET / sizeof(uintptr_t)) + 1] = (uintptr_t)dlsym,
[(RTLD_OBJ_DLOPEN_OFFSET / sizeof(uintptr_t)) + 2] = (uintptr_t)dlerror,
[(RTLD_OBJ_DLOPEN_OFFSET / sizeof(uintptr_t)) + 3] = (uintptr_t)dlclose,
[(RTLD_OBJ_DLOPEN_OFFSET / sizeof(uintptr_t)) + 4] = (uintptr_t)dladdr,
};
#else
const uintptr_t _rtld_compat_obj[] = {
# ifdef _LP64
# if BYTE_ORDER == BIG_ENDIAN
[0] = (((uint64_t)RTLD_MAGIC) << 32) | RTLD_VERSION,
# else
[0] = (((uint64_t)RTLD_VERSION) << 32) | RTLD_MAGIC,
# endif
# else
[0] = RTLD_MAGIC,
[1] = RTLD_VERSION,
# endif
};
#endif /* RTLD_OBJ_DLOPEN_OFFSET */