aes-128

  1 #include<stdio.h>
  2 void Sub_Bytes();
  3 void Shift_Rows();
  4 void Mix_Columns();
  5 unsigned char Gf_256(unsigned char a,unsigned char b);
  6 void Add_Round_Key();
  7 void Key_Expansion(int time);
  8 
  9 
 10 unsigned char sBox[256] =        //S-box
 11 {    /*  0    1    2    3    4    5    6    7    8    9    a    b    c    d    e    f */
 12 /*0*/   0x63,0x7c,0x77,0x7b,0xf2,0x6b,0x6f,0xc5,0x30,0x01,0x67,0x2b,0xfe,0xd7,0xab,0x76,
 13 /*1*/   0xca,0x82,0xc9,0x7d,0xfa,0x59,0x47,0xf0,0xad,0xd4,0xa2,0xaf,0x9c,0xa4,0x72,0xc0,
 14 /*2*/   0xb7,0xfd,0x93,0x26,0x36,0x3f,0xf7,0xcc,0x34,0xa5,0xe5,0xf1,0x71,0xd8,0x31,0x15,
 15 /*3*/    0x04,0xc7,0x23,0xc3,0x18,0x96,0x05,0x9a,0x07,0x12,0x80,0xe2,0xeb,0x27,0xb2,0x75,
 16 /*4*/   0x09,0x83,0x2c,0x1a,0x1b,0x6e,0x5a,0xa0,0x52,0x3b,0xd6,0xb3,0x29,0xe3,0x2f,0x84,
 17 /*5*/   0x53,0xd1,0x00,0xed,0x20,0xfc,0xb1,0x5b,0x6a,0xcb,0xbe,0x39,0x4a,0x4c,0x58,0xcf,
 18 /*6*/   0xd0,0xef,0xaa,0xfb,0x43,0x4d,0x33,0x85,0x45,0xf9,0x02,0x7f,0x50,0x3c,0x9f,0xa8,
 19 /*7*/   0x51,0xa3,0x40,0x8f,0x92,0x9d,0x38,0xf5,0xbc,0xb6,0xda,0x21,0x10,0xff,0xf3,0xd2,
 20 /*8*/   0xcd,0x0c,0x13,0xec,0x5f,0x97,0x44,0x17,0xc4,0xa7,0x7e,0x3d,0x64,0x5d,0x19,0x73,
 21 /*9*/   0x60,0x81,0x4f,0xdc,0x22,0x2a,0x90,0x88,0x46,0xee,0xb8,0x14,0xde,0x5e,0x0b,0xdb,
 22 /*a*/   0xe0,0x32,0x3a,0x0a,0x49,0x06,0x24,0x5c,0xc2,0xd3,0xac,0x62,0x91,0x95,0xe4,0x79,
 23 /*b*/   0xe7,0xc8,0x37,0x6d,0x8d,0xd5,0x4e,0xa9,0x6c,0x56,0xf4,0xea,0x65,0x7a,0xae,0x08,
 24 /*c*/   0xba,0x78,0x25,0x2e,0x1c,0xa6,0xb4,0xc6,0xe8,0xdd,0x74,0x1f,0x4b,0xbd,0x8b,0x8a,
 25 /*d*/   0x70,0x3e,0xb5,0x66,0x48,0x03,0xf6,0x0e,0x61,0x35,0x57,0xb9,0x86,0xc1,0x1d,0x9e,
 26 /*e*/   0xe1,0xf8,0x98,0x11,0x69,0xd9,0x8e,0x94,0x9b,0x1e,0x87,0xe9,0xce,0x55,0x28,0xdf,
 27 /*f*/   0x8c,0xa1,0x89,0x0d,0xbf,0xe6,0x42,0x68,0x41,0x99,0x2d,0x0f,0xb0,0x54,0xbb,0x16
 28 };
 29 
 30 
 31 unsigned char state[4][4] =        //明文
 32 {
 33     0x32,0x88,0x31,0xe0,
 34     0x43,0x5a,0x31,0x37,
 35     0xf6,0x30,0x98,0x07,
 36     0xa8,0x8d,0xa2,0x34
 37 };
 38 
 39 
 40 unsigned char cipher_key[4][4] =      //密钥
 41 {
 42     0x2b,0x28,0xab,0x09,
 43     0x7e,0xae,0xf7,0xcf,
 44     0x15,0xd2,0x15,0x4f,
 45     0x16,0xa6,0x88,0x3c
 46 };
 47 
 48 
 49 unsigned char Rcon[4][10] =      //轮常量
 50 {
 51     0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x1b,0x36,
 52     0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 53     0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 54     0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
 55 };
 56 
 57 
 58 int main()
 59 {    int i,j,t;
 60     for(i=0;i<4;i++)    //打印明文
 61     {
 62         for(j=0;j<4;j++)
 63         {
 64             printf("%x  ",state[i][j]);
 65         }
 66         printf("\n");
 67     }
 68     printf("\n");
 69 
 70     Add_Round_Key();    //Round 0
 71 
 72     for(t=0;t<9;t++)    //Round 1-9
 73     {
 74         Sub_Bytes();
 75         Shift_Rows();
 76         Mix_Columns();
 77         Key_Expansion(t);
 78         Add_Round_Key();
 79     }
 80 
 81     Sub_Bytes();    //Round 10
 82     Shift_Rows();
 83     Key_Expansion(t);
 84     Add_Round_Key();
 85 
 86     for(i=0;i<4;i++)
 87     {
 88         for(j=0;j<4;j++)
 89         {
 90             printf("%x  ",state[i][j]);
 91         }
 92         printf("\n");
 93     }
 94     return 0;
 95 }
 96 
 97 
 98 void Sub_Bytes()        //字节替换
 99 {
100     int i,j;
101     for(i=0;i<4;i++)
102     {
103         for(j=0;j<4;j++)
104         {
105             state[i][j]=sBox[state[i][j]];
106         }
107     }
108 }
109 
110 
111 void Shift_Rows()    //行移位变换
112 {
113     int i,j;
114     unsigned char temp[4];
115     for(i=1;i<4;i++)
116     {
117         for(j=0;j<4;j++)
118         {
119             temp[j]=state[i][j];
120         }
121         for(j=0;j<4;j++)
122         {
123             state[i][j]=temp[(j+i)%4];
124         }
125     }
126 }
127 
128 
129 void Mix_Columns()    //列混淆变换
130 {
131     int i,j;
132     unsigned char temp[4];
133     for(j=0;j<4;j++)
134     {
135         for(i=0;i<4;i++)
136         {
137             temp[i]=state[i][j];
138         }
139         for(i=0;i<4;i++)
140         {
141             state[i][j]=Gf_256(0x02,temp[i])^Gf_256(0x03,temp[(1+i)%4])^Gf_256(0x01,temp[(2+i)%4])^Gf_256(0x01,temp[(3+i)%4]);
142         }
143     }
144 }
145 
146 
147 unsigned char Gf_256(unsigned char a,unsigned char b)    //有限域GF(28)上的乘法
148 {
149     unsigned char temp[3];
150     unsigned char res;
151     temp[0]=b;        //temp[0]=0x01*b
152     temp[1]=b<<1;    //temp[1]=0x02*b
153     if(b&0x80)        //0x80=1000 0000
154     {
155         temp[1]=temp[1]^0x1b;
156     }
157     temp[2]=temp[0]^temp[1];    //temp[2]=0x03*b
158     if(a==0x01) {res=temp[0];}
159     if(a==0x02) {res=temp[1];}
160     if(a==0x03) {res=temp[2];}
161     return res;
162 }
163 
164 
165 void Add_Round_Key()        //轮密钥加变换
166 {
167     int i,j;
168     for(j=0;j<4;j++)
169     {
170         for(i=0;i<4;i++)
171         {
172             state[i][j]=state[i][j]^cipher_key[i][j];
173         }
174     }
175 }
176 
177 
178 void Key_Expansion(int time)    //aes-128为11组纶密钥，第0组为输入密钥本身
179 {
180     int i,j;
181     unsigned char temp[4];
182     for(i=0;i<4;i++)    //取出最后一列，同时循环左移一个字节
183     {
184         temp[i]=cipher_key[(i+1)%4][3];
185     }
186     for(i=0;i<4;i++)        //取出的一列进行subbytes
187     {
188         temp[i]=sBox[temp[i]];
189     }
190     for(i=0;i<4;i++)        //生成下一组密钥第一列
191     {
192         cipher_key[i][0]=cipher_key[i][0]^temp[i]^Rcon[i][time];
193     }
194     for(j=1;j<4;j++)        //生成下一组密钥的234列
195     {
196         for(i=0;i<4;i++)
197         {
198             cipher_key[i][j]=cipher_key[i][j]^cipher_key[i][j-1];
199         }
200     }
201 }