/src/botan/build/include/botan/internal/donna128.h
Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * A minimal 128-bit integer type for curve25519-donna |
3 | | * (C) 2014 Jack Lloyd |
4 | | * |
5 | | * Botan is released under the Simplified BSD License (see license.txt) |
6 | | */ |
7 | | |
8 | | #ifndef BOTAN_CURVE25519_DONNA128_H_ |
9 | | #define BOTAN_CURVE25519_DONNA128_H_ |
10 | | |
11 | | #include <botan/mul128.h> |
12 | | |
13 | | namespace Botan { |
14 | | |
15 | | class donna128 final |
16 | | { |
17 | | public: |
18 | 0 | donna128(uint64_t ll = 0, uint64_t hh = 0) { l = ll; h = hh; } |
19 | | |
20 | | donna128(const donna128&) = default; |
21 | | donna128& operator=(const donna128&) = default; |
22 | | |
23 | | friend donna128 operator>>(const donna128& x, size_t shift) |
24 | 0 | { |
25 | 0 | donna128 z = x; |
26 | 0 | if(shift > 0) |
27 | 0 | { |
28 | 0 | const uint64_t carry = z.h << (64 - shift); |
29 | 0 | z.h = (z.h >> shift); |
30 | 0 | z.l = (z.l >> shift) | carry; |
31 | 0 | } |
32 | 0 | return z; |
33 | 0 | } |
34 | | |
35 | | friend donna128 operator<<(const donna128& x, size_t shift) |
36 | 0 | { |
37 | 0 | donna128 z = x; |
38 | 0 | if(shift > 0) |
39 | 0 | { |
40 | 0 | const uint64_t carry = z.l >> (64 - shift); |
41 | 0 | z.l = (z.l << shift); |
42 | 0 | z.h = (z.h << shift) | carry; |
43 | 0 | } |
44 | 0 | return z; |
45 | 0 | } |
46 | | |
47 | | friend uint64_t operator&(const donna128& x, uint64_t mask) |
48 | 0 | { |
49 | 0 | return x.l & mask; |
50 | 0 | } |
51 | | |
52 | | uint64_t operator&=(uint64_t mask) |
53 | 0 | { |
54 | 0 | h = 0; |
55 | 0 | l &= mask; |
56 | 0 | return l; |
57 | 0 | } |
58 | | |
59 | | donna128& operator+=(const donna128& x) |
60 | 0 | { |
61 | 0 | l += x.l; |
62 | 0 | h += x.h; |
63 | 0 |
|
64 | 0 | const uint64_t carry = (l < x.l); |
65 | 0 | h += carry; |
66 | 0 | return *this; |
67 | 0 | } |
68 | | |
69 | | donna128& operator+=(uint64_t x) |
70 | 0 | { |
71 | 0 | l += x; |
72 | 0 | const uint64_t carry = (l < x); |
73 | 0 | h += carry; |
74 | 0 | return *this; |
75 | 0 | } |
76 | | |
77 | 0 | uint64_t lo() const { return l; } |
78 | 0 | uint64_t hi() const { return h; } |
79 | | private: |
80 | | uint64_t h = 0, l = 0; |
81 | | }; |
82 | | |
83 | | inline donna128 operator*(const donna128& x, uint64_t y) |
84 | 0 | { |
85 | 0 | BOTAN_ARG_CHECK(x.hi() == 0, "High 64 bits of donna128 set to zero during multiply"); |
86 | 0 |
|
87 | 0 | uint64_t lo = 0, hi = 0; |
88 | 0 | mul64x64_128(x.lo(), y, &lo, &hi); |
89 | 0 | return donna128(lo, hi); |
90 | 0 | } |
91 | | |
92 | | inline donna128 operator*(uint64_t y, const donna128& x) |
93 | 0 | { |
94 | 0 | return x * y; |
95 | 0 | } |
96 | | |
97 | | inline donna128 operator+(const donna128& x, const donna128& y) |
98 | 0 | { |
99 | 0 | donna128 z = x; |
100 | 0 | z += y; |
101 | 0 | return z; |
102 | 0 | } |
103 | | |
104 | | inline donna128 operator+(const donna128& x, uint64_t y) |
105 | 0 | { |
106 | 0 | donna128 z = x; |
107 | 0 | z += y; |
108 | 0 | return z; |
109 | 0 | } |
110 | | |
111 | | inline donna128 operator|(const donna128& x, const donna128& y) |
112 | 0 | { |
113 | 0 | return donna128(x.lo() | y.lo(), x.hi() | y.hi()); |
114 | 0 | } |
115 | | |
116 | | inline uint64_t carry_shift(const donna128& a, size_t shift) |
117 | 0 | { |
118 | 0 | return (a >> shift).lo(); |
119 | 0 | } |
120 | | |
121 | | inline uint64_t combine_lower(const donna128& a, size_t s1, |
122 | | const donna128& b, size_t s2) |
123 | 0 | { |
124 | 0 | donna128 z = (a >> s1) | (b << s2); |
125 | 0 | return z.lo(); |
126 | 0 | } |
127 | | |
128 | | #if defined(BOTAN_TARGET_HAS_NATIVE_UINT128) |
129 | | inline uint64_t carry_shift(const uint128_t a, size_t shift) |
130 | 6.05M | { |
131 | 6.05M | return static_cast<uint64_t>(a >> shift); |
132 | 6.05M | } |
133 | | |
134 | | inline uint64_t combine_lower(const uint128_t a, size_t s1, |
135 | | const uint128_t b, size_t s2) |
136 | 1.70k | { |
137 | 1.70k | return static_cast<uint64_t>((a >> s1) | (b << s2)); |
138 | 1.70k | } |
139 | | #endif |
140 | | |
141 | | } |
142 | | |
143 | | #endif |