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			55 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			55 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Operating system specific code for generic dynamic loader functions.  Linux.
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|    Copyright (C) 2000-2024 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, see
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|    <https://www.gnu.org/licenses/>.  */
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| 
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| #include <dl-sysdep.h>
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| #include <endian.h>
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| #include <fcntl.h>
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| #include <stdint.h>
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| #include <not-cancel.h>
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| 
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| static inline uintptr_t __attribute__ ((always_inline))
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| _dl_setup_stack_chk_guard (void *dl_random)
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| {
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|   union
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|   {
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|     uintptr_t num;
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|     unsigned char bytes[sizeof (uintptr_t)];
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|   } ret;
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| 
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|   /* We need in the moment only 8 bytes on 32-bit platforms and 16
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|      bytes on 64-bit platforms.  Therefore we can use the data
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|      directly and not use the kernel-provided data to seed a PRNG.  */
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|   memcpy (ret.bytes, dl_random, sizeof (ret));
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| #if BYTE_ORDER == LITTLE_ENDIAN
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|   ret.num &= ~(uintptr_t) 0xff;
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| #elif BYTE_ORDER == BIG_ENDIAN
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|   ret.num &= ~((uintptr_t) 0xff << (8 * (sizeof (ret) - 1)));
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| #else
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| # error "BYTE_ORDER unknown"
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| #endif
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|   return ret.num;
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| }
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| 
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| static inline uintptr_t __attribute__ ((always_inline))
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| _dl_setup_pointer_guard (void *dl_random, uintptr_t stack_chk_guard)
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| {
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|   uintptr_t ret;
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|   memcpy (&ret, (char *) dl_random + sizeof (ret), sizeof (ret));
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|   return ret;
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| }
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