1 /* 2 * ck - C11 Annex K wrappers (selected functions; not complete) 3 * 4 * ck is also an abbreviation for "check". 5 * These are validating, checking functions. 6 * 7 * Copyright(c) 2016 Glenn Strauss gstrauss()gluelogic.com All rights reserved 8 * License: BSD 3-clause (same as lighttpd) 9 */ 10 #ifndef INCLUDED_CK_H 11 #define INCLUDED_CK_H 12 #ifndef __STDC_WANT_LIB_EXT1__ /*(enable C11 Annex K ext1 *_s functions)*/ 13 #define __STDC_WANT_LIB_EXT1__ 1 14 #endif 15 #include "first.h" 16 #ifdef __FreeBSD__ 17 #include <errno.h> 18 #endif 19 20 __BEGIN_DECLS 21 22 23 #ifndef RSIZE_MAX 24 #define RSIZE_MAX (SIZE_MAX >> 1) 25 typedef size_t rsize_t; 26 typedef int errno_t; 27 #endif 28 29 30 errno_t ck_getenv_s (size_t * restrict len, char * restrict value, rsize_t maxsize, const char * restrict name); 31 32 /*(ck_memclear_s() is not from C11 Annex K 33 * ck_memclear_s() is similar to memset_s() using constant byte 0 for fill)*/ 34 errno_t ck_memclear_s (void *s, rsize_t smax, rsize_t n); 35 36 /*(ck_memzero() is not from C11 Annex K 37 * ck_memzero() is a convenience wrapper around ck_memclear_s())*/ 38 static inline errno_t ck_memzero(void *s, rsize_t n); 39 static inline errno_t ck_memzero(void *s, rsize_t n) { 40 return ck_memclear_s(s, n, n); 41 } 42 43 errno_t ck_strerror_s (char *s, rsize_t maxsize, errno_t errnum); 44 45 /*(ck_memeq_const_time() is not from C11 Annex K) 46 * constant time memory compare for equality 47 * rounds to next multiple of 64 to avoid potentially leaking exact 48 * string lengths when subject to high precision timing attacks */ 49 int ck_memeq_const_time (const void *a, size_t alen, const void *b, size_t blen); 50 51 /*(ck_memeq_const_time_fixed_len() is not from C11 Annex K) 52 * constant time memory compare for equality for fixed len (e.g. digests) 53 * (padding not necessary for digests, which have fixed, defined lengths) */ 54 int ck_memeq_const_time_fixed_len (const void *a, const void *b, size_t len); 55 56 __END_DECLS 57 58 59 #endif 60