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AES的C++实现(128位密钥)

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// 写了一个AES的C++实现,仅支持128位密钥, 写得匆忙,不够规范,仅供参考。 

// AES.h 

#ifndef AES_H_ 
#define AES_H_ 

#include <bitset> 
#include <utility> 

using namespace std; 

class AES 

public: 
typedef unsigned char byte; 
static const int KEY_SIZE = 16; // 密钥长度为128位 
static const int N_ROUND = 11; 
byte plainText[16]; // 明文 
byte state[16]; // 当前分组。 
byte cipherKey[16]; // 密钥 
byte roundKey[N_ROUND][16]; //轮密钥 
byte cipherText[16]; //密文 
byte SBox[16][16]; // S盒 
byte InvSBox[16][16]; // 逆S盒 
void EncryptionProcess(); 
void DecryptionProcess(); 
void Round(const int& round); 
void InvRound(const int& round); 
void FinalRound(); 
void InvFinalRound(); 
void KeyExpansion(); 
void AddRoundKey(const int& round); 
void SubBytes(); 
void InvSubBytes(); 
void ShiftRows(); 
void InvShiftRows(); 
void MixColumns(); 
void InvMixColumns(); 
void BuildSBox(); 
void BuildInvSBox(); 
void InitialState(const byte* text); 
void InitialCipherText(); 
void InitialplainText(); 
byte GFMultplyByte(const byte& left, const byte& right); 
const byte* GFMultplyBytesMatrix(const byte* left, const byte* right); 
public: 
AES(); 
const byte* Cipher(const byte* text, const byte* key, const int& keySize); 
const byte* InvCipher(const byte* text, const byte* key, const int& keySize); 
}; 


void AES::EncryptionProcess() 
{ // 加密过程 
InitialState(plainText); 
KeyExpansion(); // 密钥扩展 
AddRoundKey(0); // 轮密钥加 
for(int i = 1; i < N_ROUND-1; ++i) 

Round(i); 

FinalRound(); 
InitialCipherText(); 


void AES::DecryptionProcess() 
{ // 解密过程 
InitialState(cipherText); 
KeyExpansion(); 
InvFinalRound(); 
for(int i = N_ROUND-2; i > 0 ; --i) 

InvRound(i); 

AddRoundKey(0); 
InitialplainText(); 


void AES::Round(const int& round) 
{ // 正常轮 
SubBytes(); 
ShiftRows(); 
MixColumns(); 
AddRoundKey(round); 


void AES::InvRound(const int& round) 
{ // 正常轮的逆 
AddRoundKey(round); 
InvMixColumns(); 
InvShiftRows(); 
InvSubBytes(); 


void AES::FinalRound() 
{ // 最后轮 
SubBytes(); 
ShiftRows(); 
AddRoundKey(N_ROUND - 1); 


void AES::InvFinalRound() 
{ // 最后轮的逆 
AddRoundKey(N_ROUND - 1); 
InvShiftRows(); 
InvSubBytes(); 


void AES::KeyExpansion() 
{ // 密钥扩展 
const byte rcon[N_ROUND][4] = { 
{0x00, 0x00, 0x00, 0x00}, 
{0x01, 0x00, 0x00, 0x00}, 
{0x02, 0x00, 0x00, 0x00}, 
{0x04, 0x00, 0x00, 0x00}, 
{0x08, 0x00, 0x00, 0x00}, 
{0x10, 0x00, 0x00, 0x00}, 
{0x20, 0x00, 0x00, 0x00}, 
{0x40, 0x00, 0x00, 0x00}, 
{0x80, 0x00, 0x00, 0x00}, 
{0x1b, 0x00, 0x00, 0x00}, 
{0x36, 0x00, 0x00, 0x00} }; 
for(int i = 0; i < 16; ++i) 

roundKey[0][i] = cipherKey[i]; 

for(int i = 0; i < 4; ++i) 
{ // roundKey[0][16]为cipherKey的转置矩阵 
for(int j = 0; j < 4; ++j) 

roundKey[0][4*i + j] = cipherKey[4*j + i]; 


for(int roundIndex = 1; roundIndex < N_ROUND; ++roundIndex) 

byte rotWord[4] = {0x00}; 
rotWord[0] = roundKey[roundIndex - 1][3]; 
rotWord[1] = roundKey[roundIndex - 1][7]; 
rotWord[2] = roundKey[roundIndex - 1][11]; 
rotWord[3] = roundKey[roundIndex - 1][15]; 
std::swap<byte>(rotWord[0], rotWord[1]); 
std::swap<byte>(rotWord[1], rotWord[2]); 
std::swap<byte>(rotWord[2], rotWord[3]); 
for(int i = 0; i < 4; ++i) 

rotWord[i] = SBox[ rotWord[i] >> 4][ rotWord[i] & 0x0f ]; 
roundKey[roundIndex][4*i] = roundKey[roundIndex - 1][4*i] ^ rotWord[i] ^ rcon[roundIndex][i]; 

for(int j = 1; j < 4; ++j) 

for(int i = 0; i < 4; ++i) 

roundKey[roundIndex][4*i + j] = roundKey[roundIndex - 1][4*i + j] ^ roundKey[roundIndex][4*i + j - 1]; 





void AES::AddRoundKey(const int& round) 
{ // 轮密钥加 
for(int i = 0; i < 16; ++i) 
{ // 利用当前分组state和第round组扩展密钥进行按位异或 
state[i] ^= roundKey[round][i]; 



void AES::SubBytes() 
{ // 字节代换 
for(int i = 0; i < 16; ++i) 

state[i] = SBox[ state[i] >> 4][ state[i] & 0x0f ]; 



void AES::InvSubBytes() 
{ // 逆字节代换 
for(int i = 0; i < 16; ++i) 

state[i] = InvSBox[ state[i] >> 4][ state[i] & 0x0f ]; 



void AES::ShiftRows() 
{ // 行变换 
//state第一行保持不变 
// Do nothing. 
//state第二行循环左移一个字节 
std::swap<byte>(state[4], state[5]); 
std::swap<byte>(state[5], state[6]); 
std::swap<byte>(state[6], state[7]); 
//state第三行循环左移两个字节 
std::swap<byte>(state[8], state[10]); 
std::swap<byte>(state[9], state[11]); 
//state第三行循环左移三个字节 
std::swap<byte>(state[14], state[15]); 
std::swap<byte>(state[13], state[14]); 
std::swap<byte>(state[12], state[13]); 


void AES::InvShiftRows() 
{ // 行变换反演 
//state第一行保持不变 
// Do nothing. 
//state第二行循环右移一个字节 
std::swap<byte>(state[6], state[7]); 
std::swap<byte>(state[5], state[6]); 
std::swap<byte>(state[4], state[5]); 
//state第三行循环右移两个字节 
std::swap<byte>(state[9], state[11]); 
std::swap<byte>(state[8], state[10]); 
//state第三行循环右移三个字节 
std::swap<byte>(state[12], state[13]); 
std::swap<byte>(state[13], state[14]); 
std::swap<byte>(state[14], state[15]); 


void AES::MixColumns() 
{ // 列混淆 
byte matrix[4][4] = { 
{0x02, 0x03, 0x01, 0x01}, 
{0x01, 0x02, 0x03, 0x01}, 
{0x01, 0x01, 0x02, 0x03}, 
{0x03, 0x01, 0x01, 0x02}}; 
const byte* temp = GFMultplyBytesMatrix((byte*)matrix, state); 
for(int i = 0; i < 16; ++i) 

state[i] = temp[i]; 

delete[] temp; 


void AES::InvMixColumns() 
{ // 列混淆反演 
byte matrix[4][4] = { 
{0x0e, 0x0b, 0x0d, 0x09}, 
{0x09, 0x0e, 0x0b, 0x0d}, 
{0x0d, 0x09, 0x0e, 0x0b}, 
{0x0b, 0x0d, 0x09, 0x0e} }; 
const byte* temp = GFMultplyBytesMatrix((byte*)matrix, state); 
for(int i = 0; i < 16; ++i) 

state[i] = temp[i]; 

delete[] temp; 


void AES::BuildSBox() 
{ // 构建S盒 
byte box[16][16] = 

/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 
/*0*/ {0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76}, 
/*1*/ {0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0}, 
/*2*/ {0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15}, 
/*3*/ {0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75}, 
/*4*/ {0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84}, 
/*5*/ {0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf}, 
/*6*/ {0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8}, 
/*7*/ {0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2}, 
/*8*/ {0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73}, 
/*9*/ {0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb}, 
/*a*/ {0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79}, 
/*b*/ {0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08}, 
/*c*/ {0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a}, 
/*d*/ {0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e}, 
/*e*/ {0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf}, 
/*f*/ {0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16} 
}; 
for(int i = 0; i < 16; ++i) 

for(int j = 0; j < 16; ++j) 

SBox[i][j] = box[i][j]; 




void AES::BuildInvSBox() 
{ // 构建逆S盒 
byte box[16][16] = 

/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 
/*0*/ {0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb}, 
/*1*/ {0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb}, 
/*2*/ {0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e}, 
/*3*/ {0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25}, 
/*4*/ {0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92}, 
/*5*/ {0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84}, 
/*6*/ {0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06}, 
/*7*/ {0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b}, 
/*8*/ {0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73}, 
/*9*/ {0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e}, 
/*a*/ {0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b}, 
/*b*/ {0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4}, 
/*c*/ {0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f}, 
/*d*/ {0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef}, 
/*e*/ {0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61}, 
/*f*/ {0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d} 
}; 
for(int i = 0; i < 16; ++i) 

for(int j = 0; j < 16; ++j) 

InvSBox[i][j] = box[i][j]; 




void AES::InitialState(const byte* text) 
{ // state初始时候为明(密)文矩阵的转置矩阵 
for(int i = 0; i < 4; ++i) 
{ //转置text存放在state中 
for(int j = 0; j < 4; ++j) 

state[4*i + j] = text[4*j + i]; 




void AES::InitialCipherText() 
{ // state被复制到输出矩阵中 
for(int i = 0; i < 4; ++i) 
{ //转置state存放在cipherText中 
for(int j = 0; j < 4; ++j) 

cipherText[4*i + j] = state[4*j + i]; 




void AES::InitialplainText() 
{ // state被复制到输入矩阵中 
for(int i = 0; i < 4; ++i) 
{ //转置state存放在plainText中 
for(int j = 0; j < 4; ++j) 

plainText[4*i + j] = state[4*j + i]; 




AES::byte AES::GFMultplyByte(const byte& left, const byte& right) 
{ //有限域GF(2^8)上的乘法 
byte temp[8]; 
bitset<8> bits((unsigned long)right); //把right化为8个二进制位存放在bits中 
temp[0] = left; 
for(int i = 1; i < 8; ++i) 

if(temp[i-1] >= 0x80) //若 (temp[i-1] 首位为"1" 

temp[i] = temp[i-1] << 1; 
temp[i] = temp[i] ^ 0x1b; //与(00011011)异或 

else 

temp[i] = temp[i-1] << 1; 


byte result = 0x00; 
for(int i = 0; i < 8; ++i) 

if(bits[i] == 1) 

result ^= temp[i]; 


return result; 


const AES::byte* AES::GFMultplyBytesMatrix(const byte* left, const byte* right) 
{ //有限域GF(2^8)上的矩阵(4*4)乘法 
AES::byte* result = new AES::byte[16]; 
for(int i = 0; i < 4; ++i) 

for(int j = 0; j < 4; ++j) 

result[4*i + j] = GFMultplyByte(left[4*i], right[j]); 
for(int k = 1; k < 4; ++k) 

result[4*i + j] ^= GFMultplyByte(left[4*i + k], right[4*k + j]); 



return result; 


AES::AES() 

BuildSBox(); 
BuildInvSBox(); 


const AES::byte* AES::Cipher(const byte* text, const byte* key, const int& keySize) 
{ // 用key给text加密 
for(int i = 0; i < 16; ++i) 

plainText[i] = text[i]; 


for(int i = 0; i < keySize; ++i) 

cipherKey[i] = key[i]; 


EncryptionProcess(); 
return cipherText; 


const AES::byte* AES::InvCipher(const byte* text, const byte* key, const int& keySize) 
{ // 用key给text解密 
for(int i = 0; i < 16; ++i) 

cipherText[i] = text[i]; 


for(int i = 0; i < keySize; ++i) 

cipherKey[i] = key[i]; 


DecryptionProcess(); 
return plainText; 


#endif /* AES_H_ */ 



// main.cpp 

#include <string> 
#include <fstream> 
#include <iostream> 
#include "AES.h" 

using namespace std; 

int main(int argc, char* argv[]) 


const string USAGE = "Usage: AES [-E | -D] destinationfile sourcefile keyfile "; 

if(argc != 5) 

cout << USAGE << endl; 
return 1; 

ifstream is(argv[3], ios::in | ios::binary); 
if(!is) 

cerr << "InputFileNotFoundException" << endl; 
return 2; 


ifstream ks(argv[4], ios::in | ios::binary); 
if(!ks) 

cerr << "KeyFileNotFoundException" << endl; 
return 2; 


AES aes; 
const unsigned char *key = new unsigned char[16]; 

ks.read((char*)key, 16); 

ofstream os(argv[2], ios::out | ios::binary); 


if(strcmp(argv[1], "-E") == 0 || strcmp(argv[1], "-e") == 0) 

const unsigned char* cipherText; 
const unsigned char* plainText = new unsigned char[16]; 
while(is.read((char*)plainText, 16)) 

cipherText = aes.Cipher(plainText, key, 16); 
os.write((const char*)cipherText, 16); 



if(strcmp(argv[1], "-D") == 0 || strcmp(argv[1], "-d") == 0) 

const unsigned char* plainText; 
const unsigned char* cipherText = new unsigned char[16]; 
while(is.read((char *)cipherText, 16)) 

plainText = aes.InvCipher(cipherText, key, 16); 
os.write((const char*)plainText, 16); 

delete[] cipherText; 


delete[] key; 


is.close(); 
ks.close(); 
os.close(); 

return 0; 

Tags:密钥
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