diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/pointer_guard.h')
-rw-r--r-- | sysdeps/unix/sysv/linux/i386/pointer_guard.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/pointer_guard.h b/sysdeps/unix/sysv/linux/i386/pointer_guard.h new file mode 100644 index 0000000..a2d2a0c --- /dev/null +++ b/sysdeps/unix/sysv/linux/i386/pointer_guard.h @@ -0,0 +1,49 @@ +/* Pointer obfuscation implenentation. i386 version. + Copyright (C) 2005-2022 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 + +#include <tcb-offsets.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) xorl %gs:POINTER_GUARD, reg; \ + roll $9, reg +# define PTR_DEMANGLE(reg) rorl $9, reg; \ + xorl %gs:POINTER_GUARD, reg +# else +# define PTR_MANGLE(var) asm ("xorl %%gs:%c2, %0\n" \ + "roll $9, %0" \ + : "=r" (var) \ + : "0" (var), \ + "i" (POINTER_GUARD)) +# define PTR_DEMANGLE(var) asm ("rorl $9, %0\n" \ + "xorl %%gs:%c2, %0" \ + : "=r" (var) \ + : "0" (var), \ + "i" (POINTER_GUARD)) +# endif +#endif + +#endif /* POINTER_GUARD_H */ |