LXR linux/include/linux/string.h

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