1/*	$NetBSD: ssp.h,v 1.13 2015/09/03 20:43:47 plunky Exp $	*/
2
3/*-
4 *
5 * SPDX-License-Identifier: BSD-2-Clause
6 *
7 * Copyright (c) 2006, 2011 The NetBSD Foundation, Inc.
8 * All rights reserved.
9 *
10 * This code is derived from software contributed to The NetBSD Foundation
11 * by Christos Zoulas.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32 * POSSIBILITY OF SUCH DAMAGE.
33 */
34#ifndef _SSP_SSP_H_
35#define _SSP_SSP_H_
36
37#include <sys/cdefs.h>
38
39#if !defined(__cplusplus)
40# if defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0 && \
41     (__OPTIMIZE__ > 0 || defined(__clang__))
42#  if _FORTIFY_SOURCE > 1
43#   define __SSP_FORTIFY_LEVEL 2
44#  else
45#   define __SSP_FORTIFY_LEVEL 1
46#  endif
47# else
48#  define __SSP_FORTIFY_LEVEL 0
49# endif
50#else
51# define __SSP_FORTIFY_LEVEL 0
52#endif
53
54#define	__ssp_var(type)	__CONCAT(__ssp_ ## type, __COUNTER__)
55
56/* __ssp_real is used by the implementation in libc */
57#if __SSP_FORTIFY_LEVEL == 0
58#define __ssp_real_(fun)	fun
59#else
60#define __ssp_real_(fun)	__ssp_real_ ## fun
61#endif
62#define __ssp_real(fun)		__ssp_real_(fun)
63
64#define __ssp_inline static __inline __attribute__((__always_inline__))
65
66#define __ssp_bos(ptr) __builtin_object_size(ptr, __SSP_FORTIFY_LEVEL > 1)
67#define __ssp_bos0(ptr) __builtin_object_size(ptr, 0)
68
69#define __ssp_check(buf, len, bos) \
70	if (bos(buf) != (size_t)-1 && len > bos(buf)) \
71		__chk_fail()
72#define __ssp_redirect_raw(rtype, fun, symbol, args, call, cond, bos) \
73rtype __ssp_real_(fun) args __RENAME(symbol); \
74__ssp_inline rtype fun args __RENAME(__ssp_protected_ ## fun); \
75__ssp_inline rtype fun args { \
76	if (cond) \
77		__ssp_check(__buf, __len, bos); \
78	return __ssp_real_(fun) call; \
79}
80
81#define __ssp_redirect(rtype, fun, args, call) \
82    __ssp_redirect_raw(rtype, fun, fun, args, call, 1, __ssp_bos)
83#define __ssp_redirect0(rtype, fun, args, call) \
84    __ssp_redirect_raw(rtype, fun, fun, args, call, 1, __ssp_bos0)
85
86__BEGIN_DECLS
87void __stack_chk_fail(void) __dead2;
88void __chk_fail(void) __dead2;
89__END_DECLS
90
91#endif /* _SSP_SSP_H_ */
92