glibc/sysdeps/unix/sysv/linux/sh/pointer_guard.h

44 lines
1.7 KiB
C

/* Pointer obfuscation implenentation. Generic (no-op) version.
Copyright (C) 2005-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#ifndef POINTER_GUARD_H
#define POINTER_GUARD_H
#if IS_IN (rtld)
/* We cannot use the thread descriptor because in ld.so we use setjmp
earlier than the descriptor is initialized. Using a global variable
is too complicated here since we have no PC-relative addressing mode. */
# include <sysdeps/generic/pointer_guard.h>
#else
# ifdef __ASSEMBLER__
# define PTR_MANGLE(reg, tmp) \
stc gbr,tmp; mov.l @(POINTER_GUARD,tmp),tmp; xor tmp,reg
# define PTR_MANGLE2(reg, tmp) xor tmp,reg
# define PTR_DEMANGLE(reg, tmp) PTR_MANGLE (reg, tmp)
# define PTR_DEMANGLE2(reg, tmp) PTR_MANGLE2 (reg, tmp)
# else
# include <stdint.h>
# include <tls.h>
# define PTR_MANGLE(var) \
(var) = (void *) ((uintptr_t) (var) ^ THREAD_GET_POINTER_GUARD ())
# define PTR_DEMANGLE(var) PTR_MANGLE (var)
# endif
#endif
#endif /* POINTER_GUARD_H */