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