mirror of
				https://sourceware.org/git/glibc.git
				synced 2025-10-30 10:45:40 +03:00 
			
		
		
		
	
		
			
				
	
	
		
			50 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			50 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Pointer obfuscation implenentation.  i386 version.
 | |
|    Copyright (C) 2005-2024 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 */
 |