public static byte[] decrypt(byte[] data, byte[] key)
{
if (key == null || data == null || key.Length != 32)
{
throw new Exception("Invalid arguments!");
}
CryptoEngineAES cryptoEngineAES = new CryptoEngineAES(CryptoEngineAES.KeySize.Bits256, key);
byte[] array = new byte[data.Length];
byte[] array2 = new byte[16];
byte[] array3 = new byte[16];
for (int i = 0; i < data.Length; i += 16)
{
Array.Copy(data, i, array2, 0, 16);
cryptoEngineAES.InvCipher(array2, array3);
Array.Copy(array3, 0, array, i, 16);
}
return array;
}
private void InvMixColumns()
{
byte[,] buffer = new byte[4, 4];
for (int i = 0; i < 4; i++)
{
for (int num2 = 0; num2 < 4; num2++)
{
buffer[i, num2] = this.State[i, num2];
}
}
for (int num2 = 0; num2 < 4; num2++)
{
this.State[0, num2] = (CryptoEngineAES.gfmultby0e(buffer[0, num2]) ^ CryptoEngineAES.gfmultby0b(buffer[1, num2]) ^ CryptoEngineAES.gfmultby0d(buffer[2, num2]) ^ CryptoEngineAES.gfmultby09(buffer[3, num2]));
this.State[1, num2] = (CryptoEngineAES.gfmultby09(buffer[0, num2]) ^ CryptoEngineAES.gfmultby0e(buffer[1, num2]) ^ CryptoEngineAES.gfmultby0b(buffer[2, num2]) ^ CryptoEngineAES.gfmultby0d(buffer[3, num2]));
this.State[2, num2] = (CryptoEngineAES.gfmultby0d(buffer[0, num2]) ^ CryptoEngineAES.gfmultby09(buffer[1, num2]) ^ CryptoEngineAES.gfmultby0e(buffer[2, num2]) ^ CryptoEngineAES.gfmultby0b(buffer[3, num2]));
this.State[3, num2] = (CryptoEngineAES.gfmultby0b(buffer[0, num2]) ^ CryptoEngineAES.gfmultby0d(buffer[1, num2]) ^ CryptoEngineAES.gfmultby09(buffer[2, num2]) ^ CryptoEngineAES.gfmultby0e(buffer[3, num2]));
}
}
public static byte[] decrypt(byte[] data, byte[] key)
{
if (key == null || data == null || key.Length != 32)
{
throw new Exception("Invalid arguments!");
}
CryptoEngineAES _aesFunct = new CryptoEngineAES(CryptoEngineAES.KeySize.Bits256, key);
byte[] destinationArray = new byte[data.Length];
byte[] buffer2 = new byte[16];
byte[] output = new byte[16];
for (int i = 0; i < data.Length; i += 16)
{
Array.Copy(data, i, buffer2, 0, 16);
_aesFunct.InvCipher(buffer2, output);
Array.Copy(output, 0, destinationArray, i, 16);
}
return destinationArray;
}
public static byte[] encrypt(byte[] data, byte[] key)
{
if (key == null || data == null || key.Length != 32)
{
throw new Exception("Invalid arguments!");
}
int num = ((data.Length - 1) / 16 + 1) * 16;
byte[] array = new byte[num];
CryptoEngineAES cryptoEngineAES = new CryptoEngineAES(CryptoEngineAES.KeySize.Bits256, key);
int arg_38_0 = data.Length;
byte[] array2 = new byte[16];
byte[] array3 = new byte[16];
byte[] array4 = new byte[num];
Array.Copy(data, array4, data.Length);
for (int i = 0; i < array4.Length; i += 16)
{
Array.Copy(array4, i, array2, 0, 16);
cryptoEngineAES.Cipher(array2, array3);
Array.Copy(array3, 0, array, i, 16);
}
return array;
}
private static byte gfmultby0e(byte b)
{
return(CryptoEngineAES.gfmultby02(CryptoEngineAES.gfmultby02(CryptoEngineAES.gfmultby02(b))) ^ CryptoEngineAES.gfmultby02(CryptoEngineAES.gfmultby02(b)) ^ CryptoEngineAES.gfmultby02(b));
}
private static byte gfmultby03(byte b)
{
return(CryptoEngineAES.gfmultby02(b) ^ b);
}
private static byte gfmultby09(byte b)
{
return((byte)(CryptoEngineAES.gfmultby02(CryptoEngineAES.gfmultby02(CryptoEngineAES.gfmultby02(b))) ^ b));
}
private void SetNbNkNr(CryptoEngineAES.KeySize keySize)
{
this.Nb = 4;
if (keySize == CryptoEngineAES.KeySize.Bits128)
{
this.Nk = 4;
this.Nr = 10;
return;
}
if (keySize == CryptoEngineAES.KeySize.Bits192)
{
this.Nk = 6;
this.Nr = 12;
return;
}
if (keySize == CryptoEngineAES.KeySize.Bits256)
{
this.Nk = 8;
this.Nr = 14;
}
}
public CryptoEngineAES(CryptoEngineAES.KeySize keySize, byte[] keyBytes)
{
this.SetNbNkNr(keySize);
this.key = new byte[this.Nk * 4];
keyBytes.CopyTo(this.key, 0);
this.Sbox = new byte[,]
{
{
99,
124,
119,
123,
242,
107,
111,
197,
48,
1,
103,
43,
254,
215,
171,
118
},
{
202,
130,
201,
125,
250,
89,
71,
240,
173,
212,
162,
175,
156,
164,
114,
192
},
{
183,
253,
147,
38,
54,
63,
247,
204,
52,
165,
229,
241,
113,
216,
49,
21
},
{
4,
199,
35,
195,
24,
150,
5,
154,
7,
18,
128,
226,
235,
39,
178,
117
},
{
9,
131,
44,
26,
27,
110,
90,
160,
82,
59,
214,
179,
41,
227,
47,
132
},
{
83,
209,
0,
237,
32,
252,
177,
91,
106,
203,
190,
57,
74,
76,
88,
207
},
{
208,
239,
170,
251,
67,
77,
51,
133,
69,
249,
2,
127,
80,
60,
159,
168
},
{
81,
163,
64,
143,
146,
157,
56,
245,
188,
182,
218,
33,
16,
255,
243,
210
},
{
205,
12,
19,
236,
95,
151,
68,
23,
196,
167,
126,
61,
100,
93,
25,
115
},
{
96,
129,
79,
220,
34,
42,
144,
136,
70,
238,
184,
20,
222,
94,
11,
219
},
{
224,
50,
58,
10,
73,
6,
36,
92,
194,
211,
172,
98,
145,
149,
228,
121
},
{
231,
200,
55,
109,
141,
213,
78,
169,
108,
86,
244,
234,
101,
122,
174,
8
},
{
186,
120,
37,
46,
28,
166,
180,
198,
232,
221,
116,
31,
75,
189,
139,
138
},
{
112,
62,
181,
102,
72,
3,
246,
14,
97,
53,
87,
185,
134,
193,
29,
158
},
{
225,
248,
152,
17,
105,
217,
142,
148,
155,
30,
135,
233,
206,
85,
40,
223
},
{
140,
161,
137,
13,
191,
230,
66,
104,
65,
153,
45,
15,
176,
84,
187,
22
}
};
this.iSbox = new byte[,]
{
{
82,
9,
106,
213,
48,
54,
165,
56,
191,
64,
163,
158,
129,
243,
215,
251
},
{
124,
227,
57,
130,
155,
47,
255,
135,
52,
142,
67,
68,
196,
222,
233,
203
},
{
84,
123,
148,
50,
166,
194,
35,
61,
238,
76,
149,
11,
66,
250,
195,
78
},
{
8,
46,
161,
102,
40,
217,
36,
178,
118,
91,
162,
73,
109,
139,
209,
37
},
{
114,
248,
246,
100,
134,
104,
152,
22,
212,
164,
92,
204,
93,
101,
182,
146
},
{
108,
112,
72,
80,
253,
237,
185,
218,
94,
21,
70,
87,
167,
141,
157,
132
},
{
144,
216,
171,
0,
140,
188,
211,
10,
247,
228,
88,
5,
184,
179,
69,
6
},
{
208,
44,
30,
143,
202,
63,
15,
2,
193,
175,
189,
3,
1,
19,
138,
107
},
{
58,
145,
17,
65,
79,
103,
220,
234,
151,
242,
207,
206,
240,
180,
230,
115
},
{
150,
172,
116,
34,
231,
173,
53,
133,
226,
249,
55,
232,
28,
117,
223,
110
},
{
71,
241,
26,
113,
29,
41,
197,
137,
111,
183,
98,
14,
170,
24,
190,
27
},
{
252,
86,
62,
75,
198,
210,
121,
32,
154,
219,
192,
254,
120,
205,
90,
244
},
{
31,
221,
168,
51,
136,
7,
199,
49,
177,
18,
16,
89,
39,
128,
236,
95
},
{
96,
81,
127,
169,
25,
181,
74,
13,
45,
229,
122,
159,
147,
201,
156,
239
},
{
160,
224,
59,
77,
174,
42,
245,
176,
200,
235,
187,
60,
131,
83,
153,
97
},
{
23,
43,
4,
126,
186,
119,
214,
38,
225,
105,
20,
99,
85,
33,
12,
125
}
};
this.Rcon = new byte[,]
{
{
0,
0,
0,
0
},
{
1,
0,
0,
0
},
{
2,
0,
0,
0
},
{
4,
0,
0,
0
},
{
8,
0,
0,
0
},
{
16,
0,
0,
0
},
{
32,
0,
0,
0
},
{
64,
0,
0,
0
},
{
128,
0,
0,
0
},
{
27,
0,
0,
0
},
{
54,
0,
0,
0
}
};
this.KeyExpansion();
}
