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
| #include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <string.h>
void rc4_init(uint8_t* s, uint8_t* key, unsigned long len)
{
int i = 0;
int j = 0;
uint8_t k[256] = {0};
uint8_t temp = 0;
for (i = 0; i < 256; i++)
{
s[i] = i;
k[i] = key[i % len];
}
for (i = 0; i < 256; i++)
{
j = (j + s[i] + k[i]) % 256;
temp = s[i];
s[i] = s[j];
s[j] = temp;
}
}
void rc4_crypt(uint8_t* s, uint8_t* data, unsigned long len)
{
int i = 0, j = 0, t = 0;
uint8_t k = 0;
uint8_t temp;
for (k = 0; k < len; k++)
{
i = (i + 1) % 256;
j = (j + s[i]) % 256;
temp = s[i];
s[i] = s[j];
s[j] = temp;
t = (s[i] + s[j]) % 256;
data[k] ^= s[t];
}
}
void XTEAdecipher(unsigned int num_rounds, uint32_t v[2], uint32_t key[4]) {
unsigned int i;
uint32_t v0 = v[0], v1 = v[1], delta = 0x61C88647, sum = 0xcdab8c44;
for (i = 0; i < num_rounds; i++) {
v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + key[(sum >> 11) & 3]);
sum += delta;
v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + key[sum & 3]);
}
v[0] = v0; v[1] = v1;
}
unsigned char findPos(const unsigned char* base64_map, unsigned char c)
{
for (int i = 0; i < strlen((const char*)base64_map); i++)
{
if (base64_map[i] == c)
return i;
}
return 0;
}
unsigned char* base64_decode(const char* code0, unsigned char* base64_map)
{
unsigned char* code = (unsigned char*)code0;
long len, str_len, flag = 0;
unsigned char* res;
len = strlen((const char*)code);
if (code[len - 1] == '=')
{
if (code[len - 2] == '=')
{
flag = 1;
str_len = len / 4 * 3 - 2;
}
else
{
flag = 2;
str_len = len / 4 * 3 - 1;
}
}
else
str_len = len / 4 * 3;
res = (unsigned char*)malloc(sizeof(unsigned char) * str_len + 1);
unsigned char a[4];
for (int i = 0, j = 0; j < str_len - flag; j += 3, i += 4)
{
a[0] = findPos(base64_map, code[i]);
a[1] = findPos(base64_map, code[i + 1]);
a[2] = findPos(base64_map, code[i + 2]);
a[3] = findPos(base64_map, code[i + 3]);
res[j] = a[0] << 2 | a[1] >> 4;
res[j + 1] = a[1] << 4 | a[2] >> 2;
res[j + 2] = a[2] << 6 | a[3];
}
switch (flag)
{
case 0:
break;
case 1:
{
a[0] = findPos(base64_map,code[len - 4]);
a[1] = findPos(base64_map,code[len - 3]);
res[str_len - 1] = a[0] << 2 | a[1] >> 4;
break;
}
case 2: {
a[0] = findPos(base64_map,code[len - 4]);
a[1] = findPos(base64_map,code[len - 3]);
a[2] = findPos(base64_map,code[len - 2]);
res[str_len - 2] = a[0] << 2 | a[1] >> 4;
res[str_len - 1] = a[1] << 4 | a[2] >> 2;
break;
}
}
res[str_len] = '\0';
return res;
}
int main()
{
srand(0x1919810);
uint8_t key[16];
uint8_t key1[16];
for (int i = 0; i < 16; i++)
{
key[i] = rand() % 0xff;
key1[i] = rand() % 0xff;
}
uint8_t enc[64] = { 0x59, 0x1B, 0xFD, 0xB4, 0x6B, 0xB8, 0xBE, 0xD9, 0xB3, 0xD3, 0x77, 0xD6, 0xF0, 0x65, 0x5F, 0x18, 0xA0, 0x9D, 0x3A, 0x53, 0x6D, 0x4A, 0x7B, 0x26, 0x74, 0x3A, 0x9C, 0x4E, 0x20, 0x43, 0x19, 0xD8, 0x72, 0xED, 0x95, 0xB5, 0x9C, 0x05, 0x22, 0x56, 0xCB, 0x7A, 0x11, 0x91, 0x9F, 0x7A, 0xBC, 0x0C, 0x4A, 0x69, 0x6D, 0xCE, 0x3D, 0xB4, 0xAB, 0x29, 0x61, 0xFA, 0x62, 0x32, 0xB4, 0xEC, 0x4C, 0xB6 };
uint8_t s[256] = { 0 };
for (size_t i = 0; i < 64; i += 8)
{
XTEAdecipher(100,(uint32_t*)(enc + i), (uint32_t*)key1);
}
rc4_init(s, key, 16);
rc4_crypt(s, enc, 64);
for (int i = 0; i < 64; i++)
{
printf("%c", enc[i]);
}
printf("\n");
int v6 = 0;
int v4 = 0;
srand(0x114514);
unsigned char b64[] ="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
unsigned char tmp;
for(int i =0;i<100;i++){
v6 = rand() % 64;
v4 = rand() % 64;
tmp = b64[v6];
b64[v6] = b64[v4];
b64[v4] = tmp;
}
for (int i = 0; i < 64; i++)
{
printf("%c", b64[i]);
}
printf("\n");
printf("%s", base64_decode((char *)enc,b64));
return 0;
}
|
