1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/*
* (C) 2019 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/sodium.h>
#include <botan/chacha.h>
#include <botan/mem_ops.h>
#include <botan/system_rng.h>
#include <botan/internal/os_utils.h>
#include <botan/internal/ct_utils.h>
#include <botan/loadstor.h>
namespace Botan {
void Sodium::randombytes_buf(void* buf, size_t len)
{
system_rng().randomize(static_cast<uint8_t*>(buf), len);
}
uint32_t Sodium::randombytes_uniform(uint32_t upper_bound)
{
if(upper_bound <= 1)
return 0;
// Not completely uniform
uint64_t x;
randombytes_buf(&x, sizeof(x));
return x % upper_bound;
}
void Sodium::randombytes_buf_deterministic(void* buf, size_t size, const uint8_t seed[randombytes_SEEDBYTES])
{
const unsigned char nonce[12] = {
'L', 'i', 'b', 's', 'o', 'd', 'i', 'u', 'm', 'D', 'R', 'G'
};
ChaCha chacha(20);
chacha.set_key(seed, randombytes_SEEDBYTES);
chacha.set_iv(nonce, sizeof(nonce));
chacha.write_keystream(static_cast<uint8_t*>(buf), size);
}
int Sodium::crypto_verify_16(const uint8_t x[16], const uint8_t y[16])
{
return same_mem(x, y, 16);
}
int Sodium::crypto_verify_32(const uint8_t x[32], const uint8_t y[32])
{
return same_mem(x, y, 32);
}
int Sodium::crypto_verify_64(const uint8_t x[64], const uint8_t y[64])
{
return same_mem(x, y, 64);
}
void Sodium::sodium_memzero(void* ptr, size_t len)
{
secure_scrub_memory(ptr, len);
}
int Sodium::sodium_memcmp(const void* x, const void* y, size_t len)
{
const bool same = constant_time_compare(static_cast<const uint8_t*>(x), static_cast<const uint8_t*>(y), len);
return same ? 0 : -1;
}
int Sodium::sodium_compare(const uint8_t x[], const uint8_t y[], size_t len)
{
const uint8_t LT = static_cast<uint8_t>(-1);
const uint8_t EQ = 0;
const uint8_t GT = 1;
uint8_t result = EQ; // until found otherwise
for(size_t i = 0; i != len; ++i)
{
const auto is_eq = CT::Mask<uint8_t>::is_equal(x[i], y[i]);
const auto is_lt = CT::Mask<uint8_t>::is_lt(x[i], y[i]);
result = is_eq.select(result, is_lt.select(LT, GT));
}
return static_cast<int8_t>(result);
}
int Sodium::sodium_is_zero(const uint8_t b[], size_t len)
{
uint8_t sum = 0;
for(size_t i = 0; i != len; ++i)
sum |= b[i];
return static_cast<int>(CT::Mask<uint8_t>::expand(sum).if_not_set_return(1));
}
void Sodium::sodium_increment(uint8_t b[], size_t len)
{
uint8_t carry = 1;
for(size_t i = 0; i != len; ++i)
{
b[i] += carry;
carry &= (b[i] == 0);
}
}
void Sodium::sodium_add(uint8_t a[], const uint8_t b[], size_t len)
{
uint8_t carry = 0;
for(size_t i = 0; i != len; ++i)
{
a[i] += b[i] + carry;
carry = (a[i] < b[i]);
}
}
void* Sodium::sodium_malloc(size_t size)
{
const uint64_t len = size;
if(size + sizeof(len) < size)
return nullptr;
uint8_t* p = static_cast<uint8_t*>(std::calloc(size + sizeof(len), 1));
store_le(len, p);
return p + 8;
}
void Sodium::sodium_free(void* ptr)
{
if(ptr == nullptr)
return;
uint8_t* p = static_cast<uint8_t*>(ptr) - 8;
const uint64_t len = load_le<uint64_t>(p, 0);
secure_scrub_memory(ptr, static_cast<size_t>(len));
std::free(p);
}
void* Sodium::sodium_allocarray(size_t count, size_t size)
{
const size_t bytes = count * size;
if(bytes < count || bytes < size)
return nullptr;
return sodium_malloc(bytes);
}
int Sodium::sodium_mprotect_noaccess(void* ptr)
{
OS::page_prohibit_access(ptr);
return 0;
}
int Sodium::sodium_mprotect_readwrite(void* ptr)
{
OS::page_allow_access(ptr);
return 0;
}
}
|
