EXTERNAL_HEADERS/corecrypto/cc.h

   1 /*
   2  *  cc.h
   3  *  corecrypto
   4  *
   5  *  Created on 12/16/2010
   6  *
   7  *  Copyright (c) 2010,2011,2012,2014,2015 Apple Inc. All rights reserved.
   8  *
   9  */
  10
  11 #ifndef _CORECRYPTO_CC_H_
  12 #define _CORECRYPTO_CC_H_
  13
  14 #include <corecrypto/cc_config.h>
  15 #include <corecrypto/cc_error.h>
  16 #include <string.h>
  17 #include <stdint.h>
  18
  19 #if __has_feature(attribute_availability_with_replacement)
  20 #if __has_feature(attribute_availability_bridgeos)
  21   #ifndef __CC_BRIDGE_OS_DEPRECATED
  22     #define __CC_BRIDGEOS_DEPRECATED(_dep, _msg) __attribute__((availability(bridgeos,deprecated=_dep, replacement=_msg)))
  23   #endif
  24 #endif
  25
  26 #ifndef __CC_BRIDGEOS_DEPRECATED
  27   #define __CC_BRIDGEOS_DEPRECATED(_dep, _msg)
  28 #endif
  29
  30 #define cc_deprecate_with_replacement(replacement_message, ios_version, macos_version, tvos_version, watchos_version, bridgeos_version) \
  31 __attribute__((availability(macos,deprecated=macos_version,       replacement=replacement_message)))\
  32 __attribute__((availability(ios,deprecated=ios_version,           replacement=replacement_message)))\
  33 __attribute__((availability(watchos,deprecated=watchos_version,   replacement=replacement_message)))\
  34 __attribute__((availability(tvos,deprecated=tvos_version,         replacement=replacement_message)))\
  35 __CC_BRIDGEOS_DEPRECATED(bridgeos_version, replacement_message)
  36
  37 #else /* !__has_feature(attribute_availability_with_replacement) */
  38
  39 #define cc_deprecate_with_replacement(replacement_message, ios_version, macos_version, tvos_version, watchos_version, bridgeos_version)
  40
  41 #endif /* __has_feature(attribute_availability_with_replacement) */
  42
  43 /* Provide a general purpose macro concat method. */
  44 #define cc_concat_(a, b) a##b
  45 #define cc_concat(a, b) cc_concat_(a, b)
  46
  47 /* Manage asserts here because a few functions in header public files do use asserts */
  48 #if CORECRYPTO_DEBUG
  49 #define cc_assert(x) assert(x)
  50 #else
  51 #define cc_assert(x)
  52 #endif
  53
  54 #if CC_KERNEL
  55 #include <kern/assert.h>
  56 #elif CC_USE_S3
  57 #define assert(args)  // No assert in S3
  58 #else
  59 #include <assert.h>
  60 #endif
  61
  62 /* Provide a static assert that can be used to create compile-type failures. */
  63 #define cc_static_assert(e,m)                                               \
  64     enum { cc_concat(static_assert_, __COUNTER__) = 1/(int)(!!(e)) }
  65
  66 /* Declare a struct element with a guarenteed alignment of _alignment_.
  67    The resulting struct can be used to create arrays that are aligned by
  68    a certain amount.  */
  69 #define cc_aligned_struct(_alignment_)  \
  70 typedef struct { \
  71 uint8_t b[_alignment_]; \
  72 } CC_ALIGNED(_alignment_)
  73
  74 #if defined(__BIGGEST_ALIGNMENT__)
  75 #define CC_MAX_ALIGNMENT __BIGGEST_ALIGNMENT__
  76 #else
  77 #define CC_MAX_ALIGNMENT 16
  78 #endif
  79
  80 /* pads a given size to be a multiple of the biggest alignment for any type */
  81 #define cc_pad_align(_size_) ((_size_ + CC_MAX_ALIGNMENT - 1) & (~(CC_MAX_ALIGNMENT - 1)))
  82
  83 /* number of array elements used in a cc_ctx_decl */
  84 #define cc_ctx_n(_type_, _size_) ((_size_ + sizeof(_type_) - 1) / sizeof(_type_))
  85
  86 /* sizeof of a context declared with cc_ctx_decl */
  87 #define cc_ctx_sizeof(_type_, _size_) sizeof(_type_[cc_ctx_n(_type_, _size_)])
  88
  89 /*
  90   1. _alloca cannot be removed becasue this header file is compiled with both MSVC++ and with clang.
  91   2. The _MSC_VER version of cc_ctx_decl() is not compatible with the way *_decl macros as used in CommonCrypto, AppleKeyStore and SecurityFrameworks. To observe the incompatibilities and errors, use below definition. Corecrypto itself, accepts both deinitions
  92       #define cc_ctx_decl(_type_, _size_, _name_)  _type_ _name_ ## _array[cc_ctx_n(_type_, (_size_))]; _type_ *_name_ = _name_ ## _array
  93   3. Never use sizeof() operator for the variables declared with cc_ctx_decl(), because it is not be compatible with the _MSC_VER version of cc_ctx_decl().
  94  */
  95 #if defined(_MSC_VER)
  96 #include <malloc.h>
  97 #define cc_ctx_decl(_type_, _size_, _name_)  _type_ * _name_ = (_type_ *) _alloca(sizeof(_type_) * cc_ctx_n(_type_, _size_) )
  98 #else
  99 #define cc_ctx_decl(_type_, _size_, _name_)  _type_ _name_ [cc_ctx_n(_type_, _size_)]
 100 #endif
 101
 102 // cc_zero is deprecated, please use cc_clear instead.
 103 #define cc_zero(_size_,_data_) _Pragma ("corecrypto deprecation warning \"'cc_zero' macro is deprecated. Use 'cc_clear' instead.\"") cc_clear(_size_,_data_)
 104
 105 /*!
 106  @brief cc_clear(len, dst) zeroizes array dst and it will not be optimized out.
 107  @discussion It is used to clear sensitive data, particularly when the are defined in the stack
 108  @param len number of bytes to be cleared in dst
 109  @param dst input array
 110  */
 111 CC_NONNULL((2))
 112 void cc_clear(size_t len, void *dst);
 113
 114 #define cc_copy(_size_, _dst_, _src_) memcpy(_dst_, _src_, _size_)
 115
 116 CC_INLINE CC_NONNULL((2, 3, 4))
 117 void cc_xor(size_t size, void *r, const void *s, const void *t) {
 118     uint8_t *_r=(uint8_t *)r;
 119     const uint8_t *_s=(const uint8_t *)s;
 120     const uint8_t *_t=(const uint8_t *)t;
 121     while (size--) {
 122         _r[size] = _s[size] ^ _t[size];
 123     }
 124 }
 125
 126 /*!
 127  @brief cc_cmp_safe(num, pt1, pt2) compares two array ptr1 and ptr2 of num bytes.
 128  @discussion The execution time/cycles is independent of the data and therefore guarantees no leak about the data. However, the execution time depends on num.
 129  @param num  number of bytes in each array
 130  @param ptr1 input array
 131  @param ptr2 input array
 132  @return  returns 0 if the num bytes starting at ptr1 are identical to the num bytes starting at ptr2 and 1 if they are different or if num is 0 (empty arrays).
 133  */
 134 CC_NONNULL((2, 3))
 135 int cc_cmp_safe (size_t num, const void * ptr1, const void * ptr2);
 136
 137 /* Exchange S and T of any type.  NOTE: Both and S and T are evaluated
 138    mutliple times and MUST NOT be expressions. */
 139 #define CC_SWAP(S,T)  do { \
 140     volatile __typeof__(S) _cc_swap_tmp = S; S = T; T = _cc_swap_tmp; \
 141     _cc_swap_tmp = 0;\
 142 } while(0)
 143
 144 /* Return the maximum value between S and T. */
 145 #define CC_MAX(S, T) ({__typeof__(S) _cc_max_s = S; __typeof__(T) _cc_max_t = T; _cc_max_s > _cc_max_t ? _cc_max_s : _cc_max_t;})
 146
 147 /* Clone of CC_MAX() that evalutes S and T multiple times to allow nesting. */
 148 #define CC_MAX_EVAL(S, T) ((S) > (T) ? (S) : (T))
 149
 150 /* Return the minimum value between S and T. */
 151 #define CC_MIN(S, T) ({__typeof__(S) _cc_min_s = S; __typeof__(T) _cc_min_t = T; _cc_min_s <= _cc_min_t ? _cc_min_s : _cc_min_t;})
 152
 153 #endif /* _CORECRYPTO_CC_H_ */