| /* Operating system specific code for generic dynamic loader functions. |
| Copyright (C) 2009-2018 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 |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <endian.h> |
| #include <stdint.h> |
| |
| static inline uintptr_t __attribute__ ((always_inline)) |
| _dl_setup_stack_chk_guard (void *dl_random) |
| { |
| union |
| { |
| uintptr_t num; |
| unsigned char bytes[sizeof (uintptr_t)]; |
| } ret = { 0 }; |
| |
| if (dl_random == NULL) |
| { |
| ret.bytes[sizeof (ret) - 1] = 255; |
| ret.bytes[sizeof (ret) - 2] = '\n'; |
| } |
| else |
| { |
| memcpy (ret.bytes, dl_random, sizeof (ret)); |
| #if BYTE_ORDER == LITTLE_ENDIAN |
| ret.num &= ~(uintptr_t) 0xff; |
| #elif BYTE_ORDER == BIG_ENDIAN |
| ret.num &= ~((uintptr_t) 0xff << (8 * (sizeof (ret) - 1))); |
| #else |
| # error "BYTE_ORDER unknown" |
| #endif |
| } |
| return ret.num; |
| } |
| |
| static inline uintptr_t __attribute__ ((always_inline)) |
| _dl_setup_pointer_guard (void *dl_random, uintptr_t stack_chk_guard) |
| { |
| uintptr_t ret; |
| if (dl_random == NULL) |
| ret = stack_chk_guard; |
| else |
| memcpy (&ret, (char *) dl_random + sizeof (ret), sizeof (ret)); |
| return ret; |
| } |