1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _LINUX_STRING_H_ |
3 | #define _LINUX_STRING_H_ |
4 | |
5 | |
6 | #include <linux/compiler.h> /* for inline */ |
7 | #include <linux/types.h> /* for size_t */ |
8 | #include <linux/stddef.h> /* for NULL */ |
9 | #include <stdarg.h> |
10 | #include <uapi/linux/string.h> |
11 | |
12 | extern char *strndup_user(const char __user *, long); |
13 | extern void *memdup_user(const void __user *, size_t); |
14 | extern void *vmemdup_user(const void __user *, size_t); |
15 | extern void *memdup_user_nul(const void __user *, size_t); |
16 | |
17 | /* |
18 | * Include machine specific inline routines |
19 | */ |
20 | #include <asm/string.h> |
21 | |
22 | #ifndef __HAVE_ARCH_STRCPY |
23 | extern char * strcpy(char *,const char *); |
24 | #endif |
25 | #ifndef __HAVE_ARCH_STRNCPY |
26 | extern char * strncpy(char *,const char *, __kernel_size_t); |
27 | #endif |
28 | #ifndef __HAVE_ARCH_STRLCPY |
29 | size_t strlcpy(char *, const char *, size_t); |
30 | #endif |
31 | #ifndef __HAVE_ARCH_STRSCPY |
32 | ssize_t strscpy(char *, const char *, size_t); |
33 | #endif |
34 | #ifndef __HAVE_ARCH_STRCAT |
35 | extern char * strcat(char *, const char *); |
36 | #endif |
37 | #ifndef __HAVE_ARCH_STRNCAT |
38 | extern char * strncat(char *, const char *, __kernel_size_t); |
39 | #endif |
40 | #ifndef __HAVE_ARCH_STRLCAT |
41 | extern size_t strlcat(char *, const char *, __kernel_size_t); |
42 | #endif |
43 | #ifndef __HAVE_ARCH_STRCMP |
44 | extern int strcmp(const char *,const char *); |
45 | #endif |
46 | #ifndef __HAVE_ARCH_STRNCMP |
47 | extern int strncmp(const char *,const char *,__kernel_size_t); |
48 | #endif |
49 | #ifndef __HAVE_ARCH_STRCASECMP |
50 | extern int strcasecmp(const char *s1, const char *s2); |
51 | #endif |
52 | #ifndef __HAVE_ARCH_STRNCASECMP |
53 | extern int strncasecmp(const char *s1, const char *s2, size_t n); |
54 | #endif |
55 | #ifndef __HAVE_ARCH_STRCHR |
56 | extern char * strchr(const char *,int); |
57 | #endif |
58 | #ifndef __HAVE_ARCH_STRCHRNUL |
59 | extern char * strchrnul(const char *,int); |
60 | #endif |
61 | #ifndef __HAVE_ARCH_STRNCHR |
62 | extern char * strnchr(const char *, size_t, int); |
63 | #endif |
64 | #ifndef __HAVE_ARCH_STRRCHR |
65 | extern char * strrchr(const char *,int); |
66 | #endif |
67 | extern char * __must_check skip_spaces(const char *); |
68 | |
69 | extern char *strim(char *); |
70 | |
71 | static inline __must_check char *strstrip(char *str) |
72 | { |
73 | return strim(str); |
74 | } |
75 | |
76 | #ifndef __HAVE_ARCH_STRSTR |
77 | extern char * strstr(const char *, const char *); |
78 | #endif |
79 | #ifndef __HAVE_ARCH_STRNSTR |
80 | extern char * strnstr(const char *, const char *, size_t); |
81 | #endif |
82 | #ifndef __HAVE_ARCH_STRLEN |
83 | extern __kernel_size_t strlen(const char *); |
84 | #endif |
85 | #ifndef __HAVE_ARCH_STRNLEN |
86 | extern __kernel_size_t strnlen(const char *,__kernel_size_t); |
87 | #endif |
88 | #ifndef __HAVE_ARCH_STRPBRK |
89 | extern char * strpbrk(const char *,const char *); |
90 | #endif |
91 | #ifndef __HAVE_ARCH_STRSEP |
92 | extern char * strsep(char **,const char *); |
93 | #endif |
94 | #ifndef __HAVE_ARCH_STRSPN |
95 | extern __kernel_size_t strspn(const char *,const char *); |
96 | #endif |
97 | #ifndef __HAVE_ARCH_STRCSPN |
98 | extern __kernel_size_t strcspn(const char *,const char *); |
99 | #endif |
100 | |
101 | #ifndef __HAVE_ARCH_MEMSET |
102 | extern void * memset(void *,int,__kernel_size_t); |
103 | #endif |
104 | |
105 | #ifndef __HAVE_ARCH_MEMSET16 |
106 | extern void *memset16(uint16_t *, uint16_t, __kernel_size_t); |
107 | #endif |
108 | |
109 | #ifndef __HAVE_ARCH_MEMSET32 |
110 | extern void *memset32(uint32_t *, uint32_t, __kernel_size_t); |
111 | #endif |
112 | |
113 | #ifndef __HAVE_ARCH_MEMSET64 |
114 | extern void *memset64(uint64_t *, uint64_t, __kernel_size_t); |
115 | #endif |
116 | |
117 | static inline void *memset_l(unsigned long *p, unsigned long v, |
118 | __kernel_size_t n) |
119 | { |
120 | if (BITS_PER_LONG == 32) |
121 | return memset32((uint32_t *)p, v, n); |
122 | else |
123 | return memset64((uint64_t *)p, v, n); |
124 | } |
125 | |
126 | static inline void *memset_p(void **p, void *v, __kernel_size_t n) |
127 | { |
128 | if (BITS_PER_LONG == 32) |
129 | return memset32((uint32_t *)p, (uintptr_t)v, n); |
130 | else |
131 | return memset64((uint64_t *)p, (uintptr_t)v, n); |
132 | } |
133 | |
134 | extern void **__memcat_p(void **a, void **b); |
135 | #define memcat_p(a, b) ({ \ |
136 | BUILD_BUG_ON_MSG(!__same_type(*(a), *(b)), \ |
137 | "type mismatch in memcat_p()"); \ |
138 | (typeof(*a) *)__memcat_p((void **)(a), (void **)(b)); \ |
139 | }) |
140 | |
141 | #ifndef __HAVE_ARCH_MEMCPY |
142 | extern void * memcpy(void *,const void *,__kernel_size_t); |
143 | #endif |
144 | #ifndef __HAVE_ARCH_MEMMOVE |
145 | extern void * memmove(void *,const void *,__kernel_size_t); |
146 | #endif |
147 | #ifndef __HAVE_ARCH_MEMSCAN |
148 | extern void * memscan(void *,int,__kernel_size_t); |
149 | #endif |
150 | #ifndef __HAVE_ARCH_MEMCMP |
151 | extern int memcmp(const void *,const void *,__kernel_size_t); |
152 | #endif |
153 | #ifndef __HAVE_ARCH_MEMCHR |
154 | extern void * memchr(const void *,int,__kernel_size_t); |
155 | #endif |
156 | #ifndef __HAVE_ARCH_MEMCPY_MCSAFE |
157 | static inline __must_check unsigned long memcpy_mcsafe(void *dst, |
158 | const void *src, size_t cnt) |
159 | { |
160 | memcpy(dst, src, cnt); |
161 | return 0; |
162 | } |
163 | #endif |
164 | #ifndef __HAVE_ARCH_MEMCPY_FLUSHCACHE |
165 | static inline void memcpy_flushcache(void *dst, const void *src, size_t cnt) |
166 | { |
167 | memcpy(dst, src, cnt); |
168 | } |
169 | #endif |
170 | void *memchr_inv(const void *s, int c, size_t n); |
171 | char *strreplace(char *s, char old, char new); |
172 | |
173 | extern void kfree_const(const void *x); |
174 | |
175 | extern char *kstrdup(const char *s, gfp_t gfp) __malloc; |
176 | extern const char *kstrdup_const(const char *s, gfp_t gfp); |
177 | extern char *kstrndup(const char *s, size_t len, gfp_t gfp); |
178 | extern void *kmemdup(const void *src, size_t len, gfp_t gfp); |
179 | extern char *kmemdup_nul(const char *s, size_t len, gfp_t gfp); |
180 | |
181 | extern char **argv_split(gfp_t gfp, const char *str, int *argcp); |
182 | extern void argv_free(char **argv); |
183 | |
184 | extern bool sysfs_streq(const char *s1, const char *s2); |
185 | extern int kstrtobool(const char *s, bool *res); |
186 | static inline int strtobool(const char *s, bool *res) |
187 | { |
188 | return kstrtobool(s, res); |
189 | } |
190 | |
191 | int match_string(const char * const *array, size_t n, const char *string); |
192 | int __sysfs_match_string(const char * const *array, size_t n, const char *s); |
193 | |
194 | /** |
195 | * sysfs_match_string - matches given string in an array |
196 | * @_a: array of strings |
197 | * @_s: string to match with |
198 | * |
199 | * Helper for __sysfs_match_string(). Calculates the size of @a automatically. |
200 | */ |
201 | #define sysfs_match_string(_a, _s) __sysfs_match_string(_a, ARRAY_SIZE(_a), _s) |
202 | |
203 | #ifdef CONFIG_BINARY_PRINTF |
204 | int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args); |
205 | int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf); |
206 | int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) __printf(3, 4); |
207 | #endif |
208 | |
209 | extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos, |
210 | const void *from, size_t available); |
211 | |
212 | /** |
213 | * strstarts - does @str start with @prefix? |
214 | * @str: string to examine |
215 | * @prefix: prefix to look for. |
216 | */ |
217 | static inline bool strstarts(const char *str, const char *prefix) |
218 | { |
219 | return strncmp(str, prefix, strlen(prefix)) == 0; |
220 | } |
221 | |
222 | size_t memweight(const void *ptr, size_t bytes); |
223 | void memzero_explicit(void *s, size_t count); |
224 | |
225 | /** |
226 | * kbasename - return the last part of a pathname. |
227 | * |
228 | * @path: path to extract the filename from. |
229 | */ |
230 | static inline const char *kbasename(const char *path) |
231 | { |
232 | const char *tail = strrchr(path, '/'); |
233 | return tail ? tail + 1 : path; |
234 | } |
235 | |
236 | #define __FORTIFY_INLINE extern __always_inline __attribute__((gnu_inline)) |
237 | #define __RENAME(x) __asm__(#x) |
238 | |
239 | void fortify_panic(const char *name) __noreturn __cold; |
240 | void __read_overflow(void) __compiletime_error("detected read beyond size of object passed as 1st parameter" ); |
241 | void __read_overflow2(void) __compiletime_error("detected read beyond size of object passed as 2nd parameter" ); |
242 | void __read_overflow3(void) __compiletime_error("detected read beyond size of object passed as 3rd parameter" ); |
243 | void __write_overflow(void) __compiletime_error("detected write beyond size of object passed as 1st parameter" ); |
244 | |
245 | #if !defined(__NO_FORTIFY) && defined(__OPTIMIZE__) && defined(CONFIG_FORTIFY_SOURCE) |
246 | __FORTIFY_INLINE char *strncpy(char *p, const char *q, __kernel_size_t size) |
247 | { |
248 | size_t p_size = __builtin_object_size(p, 0); |
249 | if (__builtin_constant_p(size) && p_size < size) |
250 | __write_overflow(); |
251 | if (p_size < size) |
252 | fortify_panic(__func__); |
253 | return __builtin_strncpy(p, q, size); |
254 | } |
255 | |
256 | __FORTIFY_INLINE char *strcat(char *p, const char *q) |
257 | { |
258 | size_t p_size = __builtin_object_size(p, 0); |
259 | if (p_size == (size_t)-1) |
260 | return __builtin_strcat(p, q); |
261 | if (strlcat(p, q, p_size) >= p_size) |
262 | fortify_panic(__func__); |
263 | return p; |
264 | } |
265 | |
266 | __FORTIFY_INLINE __kernel_size_t strlen(const char *p) |
267 | { |
268 | __kernel_size_t ret; |
269 | size_t p_size = __builtin_object_size(p, 0); |
270 | |
271 | /* Work around gcc excess stack consumption issue */ |
272 | if (p_size == (size_t)-1 || |
273 | (__builtin_constant_p(p[p_size - 1]) && p[p_size - 1] == '\0')) |
274 | return __builtin_strlen(p); |
275 | ret = strnlen(p, p_size); |
276 | if (p_size <= ret) |
277 | fortify_panic(__func__); |
278 | return ret; |
279 | } |
280 | |
281 | extern __kernel_size_t __real_strnlen(const char *, __kernel_size_t) __RENAME(strnlen); |
282 | __FORTIFY_INLINE __kernel_size_t strnlen(const char *p, __kernel_size_t maxlen) |
283 | { |
284 | size_t p_size = __builtin_object_size(p, 0); |
285 | __kernel_size_t ret = __real_strnlen(p, maxlen < p_size ? maxlen : p_size); |
286 | if (p_size <= ret && maxlen != ret) |
287 | fortify_panic(__func__); |
288 | return ret; |
289 | } |
290 | |
291 | /* defined after fortified strlen to reuse it */ |
292 | extern size_t __real_strlcpy(char *, const char *, size_t) __RENAME(strlcpy); |
293 | __FORTIFY_INLINE size_t strlcpy(char *p, const char *q, size_t size) |
294 | { |
295 | size_t ret; |
296 | size_t p_size = __builtin_object_size(p, 0); |
297 | size_t q_size = __builtin_object_size(q, 0); |
298 | if (p_size == (size_t)-1 && q_size == (size_t)-1) |
299 | return __real_strlcpy(p, q, size); |
300 | ret = strlen(q); |
301 | if (size) { |
302 | size_t len = (ret >= size) ? size - 1 : ret; |
303 | if (__builtin_constant_p(len) && len >= p_size) |
304 | __write_overflow(); |
305 | if (len >= p_size) |
306 | fortify_panic(__func__); |
307 | __builtin_memcpy(p, q, len); |
308 | p[len] = '\0'; |
309 | } |
310 | return ret; |
311 | } |
312 | |
313 | /* defined after fortified strlen and strnlen to reuse them */ |
314 | __FORTIFY_INLINE char *strncat(char *p, const char *q, __kernel_size_t count) |
315 | { |
316 | size_t p_len, copy_len; |
317 | size_t p_size = __builtin_object_size(p, 0); |
318 | size_t q_size = __builtin_object_size(q, 0); |
319 | if (p_size == (size_t)-1 && q_size == (size_t)-1) |
320 | return __builtin_strncat(p, q, count); |
321 | p_len = strlen(p); |
322 | copy_len = strnlen(q, count); |
323 | if (p_size < p_len + copy_len + 1) |
324 | fortify_panic(__func__); |
325 | __builtin_memcpy(p + p_len, q, copy_len); |
326 | p[p_len + copy_len] = '\0'; |
327 | return p; |
328 | } |
329 | |
330 | __FORTIFY_INLINE void *memset(void *p, int c, __kernel_size_t size) |
331 | { |
332 | size_t p_size = __builtin_object_size(p, 0); |
333 | if (__builtin_constant_p(size) && p_size < size) |
334 | __write_overflow(); |
335 | if (p_size < size) |
336 | fortify_panic(__func__); |
337 | return __builtin_memset(p, c, size); |
338 | } |
339 | |
340 | __FORTIFY_INLINE void *memcpy(void *p, const void *q, __kernel_size_t size) |
341 | { |
342 | size_t p_size = __builtin_object_size(p, 0); |
343 | size_t q_size = __builtin_object_size(q, 0); |
344 | if (__builtin_constant_p(size)) { |
345 | if (p_size < size) |
346 | __write_overflow(); |
347 | if (q_size < size) |
348 | __read_overflow2(); |
349 | } |
350 | if (p_size < size || q_size < size) |
351 | fortify_panic(__func__); |
352 | return __builtin_memcpy(p, q, size); |
353 | } |
354 | |
355 | __FORTIFY_INLINE void *memmove(void *p, const void *q, __kernel_size_t size) |
356 | { |
357 | size_t p_size = __builtin_object_size(p, 0); |
358 | size_t q_size = __builtin_object_size(q, 0); |
359 | if (__builtin_constant_p(size)) { |
360 | if (p_size < size) |
361 | __write_overflow(); |
362 | if (q_size < size) |
363 | __read_overflow2(); |
364 | } |
365 | if (p_size < size || q_size < size) |
366 | fortify_panic(__func__); |
367 | return __builtin_memmove(p, q, size); |
368 | } |
369 | |
370 | extern void *__real_memscan(void *, int, __kernel_size_t) __RENAME(memscan); |
371 | __FORTIFY_INLINE void *memscan(void *p, int c, __kernel_size_t size) |
372 | { |
373 | size_t p_size = __builtin_object_size(p, 0); |
374 | if (__builtin_constant_p(size) && p_size < size) |
375 | __read_overflow(); |
376 | if (p_size < size) |
377 | fortify_panic(__func__); |
378 | return __real_memscan(p, c, size); |
379 | } |
380 | |
381 | __FORTIFY_INLINE int memcmp(const void *p, const void *q, __kernel_size_t size) |
382 | { |
383 | size_t p_size = __builtin_object_size(p, 0); |
384 | size_t q_size = __builtin_object_size(q, 0); |
385 | if (__builtin_constant_p(size)) { |
386 | if (p_size < size) |
387 | __read_overflow(); |
388 | if (q_size < size) |
389 | __read_overflow2(); |
390 | } |
391 | if (p_size < size || q_size < size) |
392 | fortify_panic(__func__); |
393 | return __builtin_memcmp(p, q, size); |
394 | } |
395 | |
396 | __FORTIFY_INLINE void *memchr(const void *p, int c, __kernel_size_t size) |
397 | { |
398 | size_t p_size = __builtin_object_size(p, 0); |
399 | if (__builtin_constant_p(size) && p_size < size) |
400 | __read_overflow(); |
401 | if (p_size < size) |
402 | fortify_panic(__func__); |
403 | return __builtin_memchr(p, c, size); |
404 | } |
405 | |
406 | void *__real_memchr_inv(const void *s, int c, size_t n) __RENAME(memchr_inv); |
407 | __FORTIFY_INLINE void *memchr_inv(const void *p, int c, size_t size) |
408 | { |
409 | size_t p_size = __builtin_object_size(p, 0); |
410 | if (__builtin_constant_p(size) && p_size < size) |
411 | __read_overflow(); |
412 | if (p_size < size) |
413 | fortify_panic(__func__); |
414 | return __real_memchr_inv(p, c, size); |
415 | } |
416 | |
417 | extern void *__real_kmemdup(const void *src, size_t len, gfp_t gfp) __RENAME(kmemdup); |
418 | __FORTIFY_INLINE void *kmemdup(const void *p, size_t size, gfp_t gfp) |
419 | { |
420 | size_t p_size = __builtin_object_size(p, 0); |
421 | if (__builtin_constant_p(size) && p_size < size) |
422 | __read_overflow(); |
423 | if (p_size < size) |
424 | fortify_panic(__func__); |
425 | return __real_kmemdup(p, size, gfp); |
426 | } |
427 | |
428 | /* defined after fortified strlen and memcpy to reuse them */ |
429 | __FORTIFY_INLINE char *strcpy(char *p, const char *q) |
430 | { |
431 | size_t p_size = __builtin_object_size(p, 0); |
432 | size_t q_size = __builtin_object_size(q, 0); |
433 | if (p_size == (size_t)-1 && q_size == (size_t)-1) |
434 | return __builtin_strcpy(p, q); |
435 | memcpy(p, q, strlen(q) + 1); |
436 | return p; |
437 | } |
438 | |
439 | #endif |
440 | |
441 | /** |
442 | * memcpy_and_pad - Copy one buffer to another with padding |
443 | * @dest: Where to copy to |
444 | * @dest_len: The destination buffer size |
445 | * @src: Where to copy from |
446 | * @count: The number of bytes to copy |
447 | * @pad: Character to use for padding if space is left in destination. |
448 | */ |
449 | static inline void memcpy_and_pad(void *dest, size_t dest_len, |
450 | const void *src, size_t count, int pad) |
451 | { |
452 | if (dest_len > count) { |
453 | memcpy(dest, src, count); |
454 | memset(dest + count, pad, dest_len - count); |
455 | } else |
456 | memcpy(dest, src, dest_len); |
457 | } |
458 | |
459 | /** |
460 | * str_has_prefix - Test if a string has a given prefix |
461 | * @str: The string to test |
462 | * @prefix: The string to see if @str starts with |
463 | * |
464 | * A common way to test a prefix of a string is to do: |
465 | * strncmp(str, prefix, sizeof(prefix) - 1) |
466 | * |
467 | * But this can lead to bugs due to typos, or if prefix is a pointer |
468 | * and not a constant. Instead use str_has_prefix(). |
469 | * |
470 | * Returns: 0 if @str does not start with @prefix |
471 | strlen(@prefix) if @str does start with @prefix |
472 | */ |
473 | static __always_inline size_t str_has_prefix(const char *str, const char *prefix) |
474 | { |
475 | size_t len = strlen(prefix); |
476 | return strncmp(str, prefix, len) == 0 ? len : 0; |
477 | } |
478 | |
479 | #endif /* _LINUX_STRING_H_ */ |
480 | |