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 | /* Provide a general purpose macro concat method. */ |
20 | #define cc_concat_(a, b) a##b |
21 | #define cc_concat(a, b) cc_concat_(a, b) |
22 | |
23 | /* Manage asserts here because a few functions in header public files do use asserts */ |
24 | #define cc_assert(x) assert(x) |
25 | #if CC_KERNEL |
26 | #include <kern/assert.h> |
27 | #elif CC_USE_S3 |
28 | #define assert(args) // No assert in S3 |
29 | #else |
30 | #include <assert.h> |
31 | #endif |
32 | |
33 | /* Provide a static assert that can be used to create compile-type failures. */ |
34 | #define cc_static_assert(e,m) \ |
35 | ;enum { cc_concat(static_assert_, __COUNTER__) = 1/(int)(!!(e)) } |
36 | |
37 | /* Declare a struct element with a guarenteed alignment of _alignment_. |
38 | The resulting struct can be used to create arrays that are aligned by |
39 | a certain amount. */ |
40 | #define cc_aligned_struct(_alignment_) \ |
41 | typedef struct { \ |
42 | uint8_t b[_alignment_]; \ |
43 | } CC_ALIGNED(_alignment_) |
44 | |
45 | /* number of array elements used in a cc_ctx_decl */ |
46 | #define cc_ctx_n(_type_, _size_) ((_size_ + sizeof(_type_) - 1) / sizeof(_type_)) |
47 | |
48 | /* sizeof of a context declared with cc_ctx_decl */ |
49 | #define cc_ctx_sizeof(_type_, _size_) sizeof(_type_[cc_ctx_n(_type_, _size_)]) |
50 | |
51 | /* |
52 | 1. _alloca cannot be removed becasue this header file is compiled with both MSVC++ and with clang. |
53 | 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 |
54 | #define cc_ctx_decl(_type_, _size_, _name_) _type_ _name_ ## _array[cc_ctx_n(_type_, (_size_))]; _type_ *_name_ = _name_ ## _array |
55 | 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(). |
56 | */ |
57 | #if defined(_MSC_VER) |
58 | #define cc_ctx_decl(_type_, _size_, _name_) _type_ * _name_ = (_type_ *) _alloca(sizeof(_type_) * cc_ctx_n(_type_, _size_) ) |
59 | #else |
60 | #define cc_ctx_decl(_type_, _size_, _name_) _type_ _name_ [cc_ctx_n(_type_, _size_)] |
61 | #endif |
62 | |
63 | /* bzero is deprecated. memset is the way to go */ |
64 | /* FWIW, L4, HEXAGON and ARMCC even with gnu compatibility mode don't have bzero */ |
65 | #define cc_zero(_size_,_data_) memset((_data_),0 ,(_size_)) |
66 | |
67 | /*! |
68 | @brief cc_clear(len, dst) zeroizes array dst and it will not be optimized out. |
69 | @discussion It is used to clear sensitive data, particularly when the are defined in the stack |
70 | @param len number of bytes to be cleared in dst |
71 | @param dst input array |
72 | */ |
73 | CC_NONNULL((2)) |
74 | void cc_clear(size_t len, void *dst); |
75 | |
76 | #define cc_copy(_size_, _dst_, _src_) memcpy(_dst_, _src_, _size_) |
77 | |
78 | CC_INLINE CC_NONNULL((2, 3, 4)) |
79 | void cc_xor(size_t size, void *r, const void *s, const void *t) { |
80 | uint8_t *_r=(uint8_t *)r; |
81 | const uint8_t *_s=(const uint8_t *)s; |
82 | const uint8_t *_t=(const uint8_t *)t; |
83 | while (size--) { |
84 | _r[size] = _s[size] ^ _t[size]; |
85 | } |
86 | } |
87 | |
88 | /*! |
89 | @brief cc_cmp_safe(num, pt1, pt2) compares two array ptr1 and ptr2 of num bytes. |
90 | @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. |
91 | @param num number of bytes in each array |
92 | @param ptr1 input array |
93 | @param ptr2 input array |
94 | @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). |
95 | */ |
96 | CC_NONNULL((2, 3)) |
97 | int cc_cmp_safe (size_t num, const void * ptr1, const void * ptr2); |
98 | |
99 | /* Exchange S and T of any type. NOTE: Both and S and T are evaluated |
100 | mutliple times and MUST NOT be expressions. */ |
101 | #define CC_SWAP(S,T) do { \ |
102 | __typeof__(S) _cc_swap_tmp = S; S = T; T = _cc_swap_tmp; \ |
103 | } while(0) |
104 | |
105 | /* Return the maximum value between S and T. */ |
106 | #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;}) |
107 | |
108 | /* Return the minimum value between S and T. */ |
109 | #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;}) |
110 | |
111 | #endif /* _CORECRYPTO_CC_H_ */ |
112 | |