xref: /xnu-8019.80.24/osfmk/libsa/string.h (revision a325d9c4a84054e40bbe985afedcb50ab80993ea)
1 /*
2  * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*
29  * NOTICE: This file was modified by McAfee Research in 2004 to introduce
30  * support for mandatory and extensible security protections.  This notice
31  * is included in support of clause 2.2 (b) of the Apple Public License,
32  * Version 2.0.
33  */
34 /*
35  * HISTORY
36  * @OSF_COPYRIGHT@
37  */
38 #ifndef _STRING_H_
39 #define _STRING_H_      1
40 
41 #ifdef MACH_KERNEL_PRIVATE
42 #include <types.h>
43 #else
44 #include <sys/types.h>
45 #endif
46 #include <sys/cdefs.h>
47 
48 #ifdef __cplusplus
49 extern "C" {
50 #endif
51 
52 #ifndef NULL
53 #if defined (__cplusplus)
54 #if __cplusplus >= 201103L
55 #define NULL nullptr
56 #else
57 #define NULL 0
58 #endif
59 #else
60 #define NULL ((void *)0)
61 #endif
62 #endif
63 
64 extern void     *memcpy(void *dst __sized_by(n), const void *src __sized_by(n), size_t n);
65 extern int      memcmp(const void *s1 __sized_by(n), const void *s2 __sized_by(n), size_t n) __stateful_pure;
66 extern void     *memmove(void *dst __sized_by(n), const void *src __sized_by(n), size_t n);
67 extern void     *memset(void *s __sized_by(n), int, size_t n);
68 extern int      memset_s(void *s __sized_by(smax), size_t smax, int c, size_t n);
69 
70 #ifdef XNU_KERNEL_PRIVATE
71 /* memcmp_zero_ptr_aligned() checks string s of n bytes contains all zeros.
72  * Address and size of the string s must be pointer-aligned.
73  * Return 0 if true, 1 otherwise. Also return 0 if n is 0.
74  */
75 extern unsigned long memcmp_zero_ptr_aligned(const void *s __sized_by(n), size_t n) __stateful_pure;
76 #endif
77 
78 extern size_t   strlen(const char *) __stateful_pure;
79 extern size_t   strnlen(const char *, size_t) __stateful_pure;
80 
81 /* strcpy() and strncpy() are deprecated. Please use strlcpy() instead. */
82 __kpi_deprecated_arm64_macos_unavailable
83 extern char     *strcpy(char *, const char *) __deprecated;
84 
85 __kpi_deprecated_arm64_macos_unavailable
86 extern char     *strncpy(char *, const char *, size_t);
87 
88 /* strcat() and strncat() are deprecated. Please use strlcat() instead. */
89 __kpi_deprecated_arm64_macos_unavailable
90 extern char     *strcat(char *, const char *) __deprecated;
91 
92 __kpi_deprecated_arm64_macos_unavailable
93 extern char     *strncat(char *, const char *, size_t);
94 
95 extern int      strcmp(const char *, const char *) __stateful_pure;
96 extern int      strncmp(const char *, const char *, size_t) __stateful_pure;
97 
98 extern size_t   strlcpy(char *, const char *, size_t);
99 extern size_t   strlcat(char *, const char *, size_t);
100 
101 extern int      strcasecmp(const char *s1, const char *s2) __stateful_pure;
102 extern int      strncasecmp(const char *s1, const char *s2, size_t n) __stateful_pure;
103 #ifdef XNU_KERNEL_PRIVATE
104 extern const char     *strnstr(const char *s, const char *find, size_t slen) __stateful_pure;
105 #else
106 extern char     *strnstr(const char *s, const char *find, size_t slen) __stateful_pure;
107 #endif
108 extern char     *strchr(const char *s, int c) __stateful_pure;
109 #ifdef XNU_KERNEL_PRIVATE
110 extern char     *strrchr(const char *s, int c) __stateful_pure;
111 #endif
112 extern char     *STRDUP(const char *, int);
113 extern int      strprefix(const char *s1, const char *s2) __stateful_pure;
114 
115 extern int      bcmp(const void *s1 __sized_by(n), const void *s2 __sized_by(n), size_t n) __stateful_pure;
116 extern void     bcopy(const void *src __sized_by(n), void *dst __sized_by(n), size_t n);
117 extern void     bzero(void *s __sized_by(n), size_t n);
118 extern int      timingsafe_bcmp(const void *b1 __sized_by(n), const void *b2 __sized_by(n), size_t n);
119 
120 #ifdef PRIVATE
121 #include <san/memintrinsics.h>
122 #endif
123 
124 #if __has_builtin(__builtin_dynamic_object_size)
125 #define XNU_BOS __builtin_dynamic_object_size
126 #else
127 #define XNU_BOS __builtin_object_size
128 #endif
129 
130 /* __nochk_ functions for opting out of type 1 bounds checking */
131 __attribute__((always_inline)) static inline void *
__nochk_memcpy(void * dest __sized_by (len),const void * src __sized_by (len),size_t len)132 __nochk_memcpy(void *dest __sized_by(len), const void *src __sized_by(len), size_t len)
133 {
134 	return __builtin___memcpy_chk(dest, src, len, XNU_BOS(dest, 0));
135 }
136 __attribute__((always_inline)) static inline void *
__nochk_memmove(void * dest __sized_by (len),const void * src __sized_by (len),size_t len)137 __nochk_memmove(void *dest __sized_by(len), const void *src __sized_by(len), size_t len)
138 {
139 	return __builtin___memmove_chk(dest, src, len, XNU_BOS(dest, 0));
140 }
141 __attribute__((always_inline)) static inline void
__nochk_bcopy(const void * src __sized_by (len),void * dest __sized_by (len),size_t len)142 __nochk_bcopy(const void *src __sized_by(len), void *dest __sized_by(len), size_t len)
143 {
144 	__builtin___memmove_chk(dest, src, len, XNU_BOS(dest, 0));
145 }
146 
147 #if defined(__MAC_OS_X_VERSION_MIN_REQUIRED) && __MAC_OS_X_VERSION_MIN_REQUIRED < __MAC_10_13
148 /* older deployment target */
149 #elif defined(KASAN) || (defined (_FORTIFY_SOURCE) && _FORTIFY_SOURCE == 0)
150 /* _FORTIFY_SOURCE disabled */
151 #else /* _chk macros */
152 
153 #if defined XNU_KERNEL_PRIVATE || defined(_FORTIFY_SOURCE_STRICT)
154 /* Stricter checking is optional for kexts. When type is set to 1, __builtin_object_size
155  * returns the size of the closest surrounding sub-object, which would detect copying past
156  * the end of a struct member. */
157 #define BOS_COPY_TYPE 1
158 #else
159 #define BOS_COPY_TYPE 0
160 #endif
161 
162 #if __has_builtin(__builtin___memcpy_chk)
163 #define memcpy(dest, src, len) __builtin___memcpy_chk(dest, src, len, XNU_BOS(dest, BOS_COPY_TYPE))
164 #endif
165 
166 #if __has_builtin(__builtin___memmove_chk)
167 #define memmove(dest, src, len) __builtin___memmove_chk(dest, src, len, XNU_BOS(dest, BOS_COPY_TYPE))
168 #endif
169 
170 #if __has_builtin(__builtin___strncpy_chk)
171 #define strncpy(dest, src, len) __builtin___strncpy_chk(dest, src, len, XNU_BOS(dest, 1))
172 #endif
173 
174 #if __has_builtin(__builtin___strncat_chk)
175 #define strncat(dest, src, len) __builtin___strncat_chk(dest, src, len, XNU_BOS(dest, 1))
176 #endif
177 
178 #if __has_builtin(__builtin___strlcat_chk)
179 #define strlcat(dest, src, len) __builtin___strlcat_chk(dest, src, len, XNU_BOS(dest, 1))
180 #endif
181 
182 #if __has_builtin(__builtin___strlcpy_chk)
183 #define strlcpy(dest, src, len) __builtin___strlcpy_chk(dest, src, len, XNU_BOS(dest, 1))
184 #endif
185 
186 #if __has_builtin(__builtin___strcpy_chk)
187 #define strcpy(dest, src, len) __builtin___strcpy_chk(dest, src, XNU_BOS(dest, 1))
188 #endif
189 
190 #if __has_builtin(__builtin___strcat_chk)
191 #define strcat(dest, src) __builtin___strcat_chk(dest, src, XNU_BOS(dest, 1))
192 #endif
193 
194 #if __has_builtin(__builtin___memmove_chk)
195 #define bcopy(src, dest, len) __builtin___memmove_chk(dest, src, len, XNU_BOS(dest, BOS_COPY_TYPE))
196 #endif
197 
198 #if KERNEL_PRIVATE
199 /*
200  * those allow small memsets/bzeros to be reasoned about by the compiler
201  * despite using -fno-builtin
202  */
203 #ifndef memset
204 #define memset(p, c, len) __builtin_memset(p, c, len)
205 #endif
206 
207 #ifndef bzero
208 #define bzero(p, len)     __builtin_bzero(p, len)
209 #endif
210 #endif /* KERNEL_PRIVATE */
211 
212 #endif /* _chk macros */
213 #ifdef __cplusplus
214 }
215 #endif
216 
217 #endif  /* _STRING_H_ */
218