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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/***************************************************************************
* Copyright (c) Johan Mabille, Sylvain Corlay and Wolf Vollprecht *
* Copyright (c) QuantStack *
* *
* Distributed under the terms of the BSD 3-Clause License. *
* *
* The full license is in the file LICENSE, distributed with this software. *
****************************************************************************/
#include "doctest/doctest.h"
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include "xeus/xhash.hpp"
namespace xeus
{
enum class endian
{
big_endian,
little_endian,
mixed
};
inline endian endianness()
{
uint32_t utmp = 0x01020304;
char btmp[sizeof(utmp)];
std::memcpy(&btmp[0], &utmp, sizeof(utmp));
switch(btmp[0])
{
case 0x01:
return endian::big_endian;
case 0x04:
return endian::little_endian;
default:
return endian::mixed;
}
}
// Adaptation of tests provided by Austin Appleby in https://github.com/aappleby/smhasher
template <class F>
uint32_t verification_test(F f, std::size_t hashbytes)
{
uint8_t* key = new uint8_t[256];
uint8_t* hashes = new uint8_t[hashbytes * 256];
uint8_t* res = new uint8_t[hashbytes];
std::memset(key, 0, 256);
std::memset(hashes, 0, hashbytes * 256);
std::memset(res, 0, hashbytes);
// Hash keys of the form {0}, {0,1}, {0,1,2}... up to N=255,using 256-N as
// the seed
for(std::size_t i = 0; i < 256; i++)
{
key[i] = (uint8_t)i;
*reinterpret_cast<std::size_t*>(hashes + i * hashbytes) = f(key,i,256-i);
}
// Then hash the result array
*reinterpret_cast<std::size_t*>(res) = f(hashes,hashbytes*256,0);
// The first four bytes of that hash, interpreted as a little-endian integer, is our
// verification value
uint32_t verification = uint32_t((res[0] << 0) | (res[1] << 8) | (res[2] << 16) | (res[3] << 24));
delete [] key;
delete [] hashes;
delete [] res;
return verification;
}
void rand_p(void* buffer, int bytes)
{
uint32_t * blocks = reinterpret_cast<uint32_t*>(buffer);
while(bytes >= 4)
{
blocks[0] = static_cast<uint32_t>(std::rand());
blocks++;
bytes -= 4;
}
uint8_t* tail = reinterpret_cast<uint8_t*>(blocks);
for(int i = 0; i < bytes; i++)
{
tail[i] = static_cast<uint8_t>(std::rand());
}
}
void flipbit(void * block, int len, uint32_t bit)
{
uint8_t * b = (uint8_t*)block;
int byte = int(bit >> 3);
bit = bit & 0x7;
if(byte < len)
{
b[byte] ^= static_cast<uint8_t>(1 << bit);
}
}
template <class F>
bool sanity_test(F f, std::size_t hashbytes)
{
std::srand(883741);
bool result = true;
int reps = 10;
int keymax = 256;
int pad = 16;
int buflen = keymax + pad*3;
uint8_t * buffer1 = new uint8_t[std::size_t(buflen)];
uint8_t * buffer2 = new uint8_t[std::size_t(buflen)];
uint8_t * hash1 = new uint8_t[hashbytes];
uint8_t * hash2 = new uint8_t[hashbytes];
for(int irep = 0; irep < reps; irep++)
{
for(int len = 4; len <= keymax; len++)
{
for(int offset = pad; offset < pad*2; offset++)
{
uint8_t * key1 = &buffer1[pad];
uint8_t * key2 = &buffer2[pad+offset];
rand_p(buffer1,buflen);
rand_p(buffer2,buflen);
std::memcpy(key2,key1,std::size_t(len));
*reinterpret_cast<std::size_t*>(hash1) = f(key1,std::size_t(len),0);
for(int bit = 0; bit < (len * 8); bit++)
{
// Flip a bit, hash the key -> we should get a different result.
flipbit(key2,len,uint32_t(bit));
*reinterpret_cast<std::size_t*>(hash2) = f(key2,std::size_t(len),0);
if(std::memcmp(hash1,hash2,hashbytes) == 0)
{
result = false;
}
flipbit(key2,len,uint32_t(bit));
*reinterpret_cast<std::size_t*>(hash2) = f(key2,std::size_t(len),0);
if(std::memcmp(hash1,hash2,hashbytes) != 0)
{
result = false;
}
}
}
}
}
delete [] buffer1;
delete [] buffer2;
delete [] hash1;
delete [] hash2;
return result;
}
TEST_SUITE("hash") {
TEST_CASE("verification")
{
#if INTPTR_MAX == INT64_MAX
uint32_t res;
switch(endianness()) {
case endian::big_endian:
res = 0x8fda498d;
break;
case endian::little_endian:
res = sizeof(std::size_t) == 4 ? 0x27864c1e : 0x1f0d3804;
break;
default:
CHECK_MESSAGE(false, "unsupported exotic architecture");
}
#elif INTPTR_MAX == INT32_MAX
uint32_t res = sizeof(std::size_t) == 4 ? 0x27864c1e : 0xdd537c05;
#else
#error Unknown pointer size or missing size macros!
#endif
uint32_t actual = verification_test(&hash_bytes, sizeof(std::size_t));
REQUIRE_EQ(actual, res);
}
TEST_CASE("sanity")
{
REQUIRE(sanity_test(&hash_bytes, sizeof(std::size_t)));
}
}
}
|
