projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 88f4b692 | 1 | /* Pointer guard implementation. Alpha version. |
| dff8da6b | 2 | Copyright (C) 2006-2024 Free Software Foundation, Inc. |
| 88f4b692 FW |
3 | This file is part of the GNU C Library. |
| 4 | ||
| 5 | The GNU C Library is free software; you can redistribute it and/or | |
| 6 | modify it under the terms of the GNU Lesser General Public | |
| 7 | License as published by the Free Software Foundation; either | |
| 8 | version 2.1 of the License, or (at your option) any later version. | |
| 9 | ||
| 10 | The GNU C Library is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 | Lesser General Public License for more details. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Lesser General Public | |
| 16 | License along with the GNU C Library. If not, see | |
| 17 | <https://www.gnu.org/licenses/>. */ | |
| 18 | ||
| 19 | #ifndef POINTER_GUARD_H | |
| 20 | #define POINTER_GUARD_H | |
| 21 | ||
| 22 | /* Pointer mangling support. Note that tls access is slow enough that | |
| 23 | we don't deoptimize things by placing the pointer check value there. */ | |
| 24 | ||
| 25 | #ifdef __ASSEMBLER__ | |
| 26 | # if IS_IN (rtld) | |
| 27 | # define PTR_MANGLE(dst, src, tmp) \ | |
| 28 | ldah tmp, __pointer_chk_guard_local($29) !gprelhigh; \ | |
| 29 | ldq tmp, __pointer_chk_guard_local(tmp) !gprellow; \ | |
| 30 | xor src, tmp, dst | |
| 31 | # define PTR_MANGLE2(dst, src, tmp) \ | |
| 32 | xor src, tmp, dst | |
| 33 | # elif defined SHARED | |
| 34 | # define PTR_MANGLE(dst, src, tmp) \ | |
| 35 | ldq tmp, __pointer_chk_guard; \ | |
| 36 | xor src, tmp, dst | |
| 37 | # else | |
| 38 | # define PTR_MANGLE(dst, src, tmp) \ | |
| 39 | ldq tmp, __pointer_chk_guard_local; \ | |
| 40 | xor src, tmp, dst | |
| 41 | # endif | |
| 42 | # define PTR_MANGLE2(dst, src, tmp) \ | |
| 43 | xor src, tmp, dst | |
| 44 | # define PTR_DEMANGLE(dst, tmp) PTR_MANGLE(dst, dst, tmp) | |
| 45 | # define PTR_DEMANGLE2(dst, tmp) PTR_MANGLE2(dst, dst, tmp) | |
| 46 | #else | |
| 47 | # include <stdint.h> | |
| 48 | # if (IS_IN (rtld) \ | |
| 49 | || (!defined SHARED && (IS_IN (libc) \ | |
| 50 | || IS_IN (libpthread)))) | |
| 51 | extern uintptr_t __pointer_chk_guard_local attribute_relro attribute_hidden; | |
| 52 | # define PTR_MANGLE(var) \ | |
| 53 | (var) = (__typeof (var)) ((uintptr_t) (var) ^ __pointer_chk_guard_local) | |
| 54 | # else | |
| 55 | extern uintptr_t __pointer_chk_guard attribute_relro; | |
| 56 | # define PTR_MANGLE(var) \ | |
| 57 | (var) = (__typeof(var)) ((uintptr_t) (var) ^ __pointer_chk_guard) | |
| 58 | # endif | |
| 59 | # define PTR_DEMANGLE(var) PTR_MANGLE(var) | |
| 60 | #endif /* ASSEMBLER */ | |
| 61 | ||
| 62 | #endif /* POINTER_GUARD_H */ |