1 /* $NetBSD: ssp.h,v 1.16 2023/11/15 03:14:16 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2006, 2011, 2023 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 #ifndef _SSP_SSP_H_ 32 #define _SSP_SSP_H_ 33 34 #include <sys/cdefs.h> 35 36 #if !defined(__cplusplus) 37 # if _FORTIFY_SOURCE > 0 && !defined(__lint__) && \ 38 (__OPTIMIZE__ > 0 || defined(__clang__)) && __GNUC_PREREQ__(4, 1) 39 # if _FORTIFY_SOURCE > 2 && __has_builtin(__builtin_dynamic_object_size) 40 # define __SSP_FORTIFY_LEVEL 3 41 # elif _FORTIFY_SOURCE > 1 42 # define __SSP_FORTIFY_LEVEL 2 43 # else 44 # define __SSP_FORTIFY_LEVEL 1 45 # endif 46 # else 47 # define __SSP_FORTIFY_LEVEL 0 48 # endif 49 #else 50 # define __SSP_FORTIFY_LEVEL 0 51 #endif 52 53 /* __ssp_real is used by the implementation in libc */ 54 #if __SSP_FORTIFY_LEVEL == 0 55 #define __ssp_real_(fun) fun 56 #else 57 #define __ssp_real_(fun) __ssp_real_ ## fun 58 #endif 59 #define __ssp_real(fun) __ssp_real_(fun) 60 61 #ifndef __ssp_inline 62 #define __ssp_inline extern __inline \ 63 __attribute__((__always_inline__, __gnu_inline__)) 64 #endif 65 66 #if __SSP_FORTIFY_LEVEL > 2 67 # define __ssp_bos(ptr) __builtin_dynamic_object_size(ptr, 1) 68 # define __ssp_bos0(ptr) __builtin_dynamic_object_size(ptr, 0) 69 #else 70 # define __ssp_bos(ptr) __builtin_object_size(ptr, __SSP_FORTIFY_LEVEL > 1) 71 # define __ssp_bos0(ptr) __builtin_object_size(ptr, 0) 72 #endif 73 74 #define __ssp_check(buf, len, bos) \ 75 if (bos(buf) != (size_t)-1 && len > bos(buf)) \ 76 __chk_fail() 77 #define __ssp_redirect_raw(rtype, fun, symbol, args, call, cond, bos) \ 78 rtype __ssp_real_(fun) args __RENAME(symbol); \ 79 __ssp_inline rtype fun args __RENAME(__ssp_protected_ ## fun); \ 80 __ssp_inline rtype fun args { \ 81 if (cond) \ 82 __ssp_check(__buf, __len, bos); \ 83 return __ssp_real_(fun) call; \ 84 } 85 86 #define __ssp_redirect(rtype, fun, args, call) \ 87 __ssp_redirect_raw(rtype, fun, fun, args, call, 1, __ssp_bos) 88 #define __ssp_redirect0(rtype, fun, args, call) \ 89 __ssp_redirect_raw(rtype, fun, fun, args, call, 1, __ssp_bos0) 90 91 #define __ssp_overlap(a, b, l) \ 92 (((a) <= (b) && (b) < (a) + (l)) || ((b) <= (a) && (a) < (b) + (l))) 93 94 __BEGIN_DECLS 95 void __stack_chk_fail(void) __dead; 96 void __chk_fail(void) __dead; 97 __END_DECLS 98 99 #endif /* _SSP_SSP_H_ */ 100