string.h 13 KB

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