AES加解密程序
该程序实现了从文件中读取需要加/解密的内容以及密钥,进行Nb=4,Nk=4,Nr=10的AES加解密
如何使用该程序
运行程序后需先输入想要加密/解密的文件名,随后选择输入1为加密,输入2位解密。
如图,输入了文件名为test3_en.txt,选择1加密模式。
程序运行完成后会将加密后的密文写入选择的文件中。
函数说明
密钥扩展函数KeyExpansion
函数定义
void keyExpansion(unsigned char*key);
函数功能
实现轮密钥的生成
如果i不是4的倍数,那么第i列由如下等式确定:
W[i]=W[i-4]⨁W[i-1]
如果i是4的倍数,那么第i列由如下等式确定:
W[i]=W[i-4]⨁T(W[i-1])
参数说明
用户从指定文件中读取出的密钥
轮密钥加函数AddRoundKey
函数定义
void AddRoundKey(unsigned char *RoundText,int round);
函数功能
将每轮的密钥与状态进行异或
参数说明
参数1:每轮的状态
参数2:进行的轮数
S盒置换函数ByteSub
函数定义
void ByteSub(unsigned char *RoundText);
函数功能
将每轮的状态在S盒中进行置换
参数说明
每轮的状态
S盒逆置换函数InvByteSub
函数定义
void InvByteSub(unsigned char *RoundText);
函数功能
将每轮的状态在逆S盒中进行置换
参数说明
每轮的状态
行移位函数ShiftRow
函数定义
void ShiftRow(unsigned char *RoundText);
函数功能
第一行不移位,第二行左移一位。第三行左移两位,第四行左移三位。
参数说明
每轮的状态
行逆移位函数InvShiftRow
函数定义
void InvShiftRow(unsigned char *RoundText);
函数功能
第一行不移位,第二行右移一位。第三行右移两位,第四行右移三位。
参数说明
每轮的状态
xtime系列函数
函数定义
unsigned char xtime2(unsigned char x);
unsigned char xtime3(unsigned char x);
unsigned char xtime4(unsigned char x);
unsigned char xtime8(unsigned char x);
unsigned char xtime9(unsigned char x);
unsigned char xtimeB(unsigned char x);
unsigned char xtimeD(unsigned char x);
unsigned char xtimeE(unsigned char x);
函数功能
在GF(2^8)上进行x乘
参数说明
进行x乘的数
返回值
返回x乘的结果
列混合函数MixColumn
函数定义
void MixColumn(unsigned char *RoundText);
函数功能
以下图模式进行列混合
参数说明
每轮的状态
列逆混合函数InvMixColumn
函数定义
void InvMixColumn(unsigned char *RoundText);
函数功能
以下图模式进行列逆混合
参数说明
每轮的状态
加密函数AES_encrypt
函数定义
void AES_encrypt(unsigned char *RoundText);
函数功能
第一轮开始前先进行轮密钥加,中间九轮进行S盒置换、行移位、列混合、轮密钥加,最后一轮不进行列混合。
参数说明
每轮的状态
解密函数AES_decrypt
函数定义
void AES_decrypt(unsigned char *RoundText);
函数功能
第一轮开始前先进行轮密钥加、行逆移位、S盒逆置换,中间九轮进行轮密钥加、列逆混合、行逆移位、S盒逆置换,最后一轮进行S盒逆置换。
参数说明
每轮的状态
结果输出函数encrypt、decrypt
函数定义
void encrypt();
void decrypt();
函数功能
将加/解密结果输出到打开的文件中。输出两位十六进制数,以逗号为分隔。
源代码
#include <stdio.h>
#include <stdlib.h>
unsigned char SBOX[256] = {
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16
};
unsigned char R_SBOX[256] ={
0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d
};
unsigned char Rcon[10] = {
0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x1b,0x36
};
unsigned char RoundKey[11*16];
void encrypt();
void decrypt();
void AES_encrypt(unsigned char *RoundText);
void AES_decrypt(unsigned char *RoundText);
void keyExpansion(unsigned char*key);
void AddRoundKey(unsigned char *RoundText,int round);
void ByteSub(unsigned char *RoundText);
void ShiftRow(unsigned char *RoundText);
void MixColumn(unsigned char *RoundText);
void InvByteSub(unsigned char *RoundText);
void InvShiftRow(unsigned char *RoundText);
void InvMixColumn(unsigned char *RoundText);
unsigned char xtime2(unsigned char x);
unsigned char xtime3(unsigned char x);
unsigned char xtime4(unsigned char x);
unsigned char xtime8(unsigned char x);
unsigned char xtime9(unsigned char x);
unsigned char xtimeB(unsigned char x);
unsigned char xtimeD(unsigned char x);
unsigned char xtimeE(unsigned char x);
unsigned char key[16];
unsigned char text[16];
FILE *fp;
int main()
{
int choice,temp[16],temp2[16];
char filename[50];
printf("Please input the filename:");
scanf("%s",filename);
if((fp = fopen(filename,"r+")) == NULL)
{
perror("Fail to read!\n");
exit (1) ;
}
fscanf(fp,"%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x\n",
&temp[0],&temp[1],&temp[2],&temp[3],&temp[4],&temp[5],&temp[6],&temp[7],
&temp[8],&temp[9],&temp[10],&temp[11],&temp[12],&temp[13],&temp[14],&temp[15]);
fscanf(fp,"%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x\n",
&temp2[0],&temp2[1],&temp2[2],&temp2[3],&temp2[4],&temp2[5],&temp2[6],&temp2[7],
&temp2[8],&temp2[9],&temp2[10],&temp2[11],&temp2[12],&temp2[13],&temp2[14],&temp2[15]);
for (int i = 0; i < 16; i++)
{
text[i]=temp[i];
key[i]=temp2[i];
}
keyExpansion(key);
printf("Input 1: Encrypt; Input 2: Decrypt: ");
scanf("%d",&choice);
if (choice==1)
encrypt();
else decrypt();
}
void encrypt()
{
AES_encrypt(text);
fprintf(fp,"%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x\n",
text[0],text[1],text[2],text[3],text[4],text[5],text[6],text[7],
text[8],text[9],text[10],text[11],text[12],text[13],text[14],text[15]);
}
void decrypt()
{
AES_decrypt(text);
fprintf(fp,"%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x\n",
text[0],text[1],text[2],text[3],text[4],text[5],text[6],text[7],
text[8],text[9],text[10],text[11],text[12],text[13],text[14],text[15]);
}
void keyExpansion(unsigned char*key)
{
int i,j;
unsigned char temp[4],t;
for(i=0;i<4;i++)
for(j=0;j<4;j++)
RoundKey[i*4+j]=key[i*4+j];
while (i<4*11)
{
for(j=0;j<4;j++)
temp[j]=RoundKey[4*(i-1)+j];
if(i%4==0)
{
t=temp[0];temp[0]=temp[1];temp[1]=temp[2];temp[2]=temp[3];temp[3]=t;
for(j=0;j<4;j++)
temp[j]=SBOX[temp[j]];
temp[0]^=Rcon[i/4-1];
}
for(j=0;j<4;j++)
RoundKey[4*i+j]=RoundKey[4*(i-4)+j]^temp[j];
i++;
}
}
void ByteSub(unsigned char *RoundText)
{
for (int i = 0; i < 16; i++)
RoundText[i]=SBOX[RoundText[i]];
}
void InvByteSub(unsigned char *RoundText)
{
for (int i = 0; i < 16; i++)
RoundText[i]=R_SBOX[RoundText[i]];
}
void ShiftRow(unsigned char *RoundText)
{
unsigned char t;
//row1
t=RoundText[1];RoundText[1]=RoundText[5];RoundText[5]=RoundText[9];RoundText[9]=RoundText[13];RoundText[13]=t;
//row2
t=RoundText[2];RoundText[2]=RoundText[10];RoundText[10]=t;
t=RoundText[6];RoundText[6]=RoundText[14];RoundText[14]=t;
//row3
t=RoundText[15];RoundText[15]=RoundText[11];RoundText[11]=RoundText[7];RoundText[7]=RoundText[3];RoundText[3]=t;
}
void InvShiftRow(unsigned char *RoundText)
{
unsigned char t;
//row1
t=RoundText[13];RoundText[13]=RoundText[9];RoundText[9]=RoundText[5];RoundText[5]=RoundText[1];RoundText[1]=t;
//row2
t=RoundText[2];RoundText[2]=RoundText[10];RoundText[10]=t;
t=RoundText[6];RoundText[6]=RoundText[14];RoundText[14]=t;
//row3
t=RoundText[3];RoundText[3]=RoundText[7];RoundText[7]=RoundText[11];RoundText[11]=RoundText[15];RoundText[15]=t;
}
unsigned char xtime2(unsigned char x)
{
if (x&0x80)
return (((x<<1)^0x1B)&0xFF);
return x<<1;
}
unsigned char xtime3(unsigned char x)
{
return (xtime2(x)^x);
}
unsigned char xtime4(unsigned char x)
{
return (xtime2(xtime2(x)));
}
unsigned char xtime8(unsigned char x)
{
return (xtime2(xtime2(xtime2(x))));
}
unsigned char xtime9(unsigned char x)
{
return (xtime8(x)^x);
}
unsigned char xtimeB(unsigned char x)
{
return (xtime8(x)^xtime2(x)^x);
}
unsigned char xtimeD(unsigned char x)
{
return (xtime8(x)^xtime4(x)^x);
}
unsigned char xtimeE(unsigned char x)
{
return (xtime8(x)^xtime4(x)^xtime2(x));
}
void MixColumn(unsigned char *RoundText)
{
unsigned char temp[4];
for (int i = 0; i < 4; i++)
{
temp[0]=xtime2(RoundText[4*i])^xtime3(RoundText[1+4*i])^RoundText[2+4*i]^RoundText[3+4*i];
temp[1]=RoundText[4*i]^xtime2(RoundText[1+4*i])^xtime3(RoundText[2+4*i])^RoundText[3+4*i];
temp[2]=RoundText[4*i]^RoundText[1+4*i]^xtime2(RoundText[2+4*i])^xtime3(RoundText[3+4*i]);
temp[3]=xtime3(RoundText[4*i])^RoundText[1+4*i]^RoundText[2+4*i]^xtime2(RoundText[3+4*i]);
RoundText[4*i]=temp[0];
RoundText[1+4*i]=temp[1];
RoundText[2+4*i]=temp[2];
RoundText[3+4*i]=temp[3];
}
}
void InvMixColumn(unsigned char *RoundText)
{
unsigned char temp[4];
for (int i = 0; i < 4; i++)
{
temp[0]=xtimeE(RoundText[4*i])^xtimeB(RoundText[1+4*i])^xtimeD(RoundText[2+4*i])^xtime9(RoundText[3+4*i]);
temp[1]=xtime9(RoundText[4*i])^xtimeE(RoundText[1+4*i])^xtimeB(RoundText[2+4*i])^xtimeD(RoundText[3+4*i]);
temp[2]=xtimeD(RoundText[4*i])^xtime9(RoundText[1+4*i])^xtimeE(RoundText[2+4*i])^xtimeB(RoundText[3+4*i]);
temp[3]=xtimeB(RoundText[4*i])^xtimeD(RoundText[1+4*i])^xtime9(RoundText[2+4*i])^xtimeE(RoundText[3+4*i]);
RoundText[4*i]=temp[0];
RoundText[1+4*i]=temp[1];
RoundText[2+4*i]=temp[2];
RoundText[3+4*i]=temp[3];
}
}
void AddRoundKey(unsigned char *RoundText,int round)
{
for (int i = 0; i < 16; i++)
RoundText[i]^=RoundKey[round*16+i];
}
void AES_encrypt(unsigned char* RoundText)
{
int round=0;
AddRoundKey(RoundText,round);
for(round=1;round<10;round++)
{
ByteSub(RoundText);
ShiftRow(RoundText);
MixColumn(RoundText);
AddRoundKey(RoundText,round);
}
ByteSub(RoundText);
ShiftRow(RoundText);
AddRoundKey(RoundText,round);
}
void AES_decrypt(unsigned char *RoundText)
{
int round=10;
AddRoundKey(RoundText,round);
InvShiftRow(RoundText);
InvByteSub(RoundText);
for(round=9;round>0;round--)
{
AddRoundKey(RoundText,round);
InvMixColumn(RoundText);
InvShiftRow(RoundText);
InvByteSub(RoundText);
}
AddRoundKey(RoundText,round);
}
示例
加密前文件:第一行为明文,第二行为密钥
在第三行输出密文