AES/ECB---C++算法实现
密码学课后作业实现AES/ECB算法的实现，所以这几天都有在查一些AES资料，在此整理下并附上C++代码(:
这里引用一下维基上关于AES的基本介绍：
AES加密过程是在一个4×4的字节矩阵上运作，这个矩阵又称为“体（state）”，其初值就是一个明文区块（矩阵中一个元素大小就是明文区块中的一个Byte）。（Rijndael加密法因支持更大的区块，其矩阵行数可视情况增加）加密时，各轮AES加密循环（除最后一轮外）均包含4个步骤：
AddRoundKey—矩阵中的每一个字节都与该次回合密钥（round key）做XOR运算；每个子密钥由密钥生成方案产生。
SubBytes—通过一个非线性的替换函数，用查找表的方式把每个字节替换成对应的字节。
ShiftRows—将矩阵中的每个横列进行循环式移位。
MixColumns—为了充分混合矩阵中各个直行的操作。这个步骤使用线性转换来混合每内联的四个字节。最后一个加密循环中省略MixColumns步骤，而以另一个AddRoundKey取代。
（找资料的时候发现这个视频讲加密还是很清楚的，附上链接）
AddRoundKey步骤
addroundkey步骤实现的是回合密钥（round key）与当前状态（state）的异或操作。此步骤加密解密阶段都是相同的，无需更改。具体代码如下：
/* * 异或处理 */ void Aes::addRoundKey(unsigned char state[4][4], unsigned char roundKey[4][4])// already test { for(int col=0 ; col<4 ; col++){ for(int row=0 ; row<4 ; row++){ state[row][col] ^= roundKey[row][col]; } } }
SubBytes步骤
subbytes步骤实现的是根据S盒以及逆S盒进行替换操作。加密时用S盒，解密时用逆S盒。具体代码如下：
/* * 替换 already test */ void Aes::subBytes(unsigned char state[4][4]) { int x, y; int value; for(int i=0 ; i<4 ;i++){//列 for(int j=0 ; j<4 ;j++){//行 value = state[j][i]; x = value / 16 ; y = value % 16 ; state[j][i] = s_box[x*16+y]; } } } /* * 逆替换 already test */ void Aes::invSubBytes(unsigned char state[4][4]) { int col,row; int x,y; int value; for(col=0 ; col<4 ; col++){ for(row=0 ; row<4 ; row++){ value = state[row][col]; x = value / 16 ; y = value % 16 ; state[row][col] = Inv_S_Box[x][y]; } } }
ShiftRows步骤
shiftrows步骤实现的是行移位操作，第一行不动，第二行循环左移一位，第三行循环左移二位，第四行循环左移三位（这里的位具体指的是一数组元素），解密操作则是把左移改为右移即可。
/* * 移动行 already test */ void Aes::shiftRows(unsigned char state[4][4]) { unsigned char temp; int times = 0; for(int i = 1; i < 4 ; i++)//行 { times = i; while(times--) { temp = state[i][0];//每一行的第一个元素 copy一份 for(int j = 1 ; j < 4 ; j++)//列 { state[i][j-1] = state[i][j]; //左移一位 } state[i][3] = temp;//填充最后一位 } } } /* * 逆移动行 already test */ void Aes::invShiftRows(unsigned char state[4][4]) { unsigned char temp; int times = 0; int i,j; for(i = 1; i < 4 ; i++)//行 { times = i; while(times--) { temp = state[i][3];//每一行的第一个元素 copy一份 for(j=2 ; j>=0 ; j--)//列 { state[i][j+1] = state[i][j]; //左移一位 } state[i][0] = temp;//填充最后一位 } } }
MixColumns步骤
重点来了，AES与DES的最大区别，AES除了替换，位移，还有就是数学上操作（GF(28)），这里我就不详细说明了（好吧，其实是水平有限，大家可以看一下这个关于mixcolumns操作的介绍）
/* * 列处理 already test */ void Aes::mixColumns(unsigned char state[4][4]) { unsigned char copyState[4]; unsigned char state2[4]; //2倍state unsigned char h; for(int col=0 ; col<4 ; col++)//列 { //每一列操作 for(int row=0 ; row<4 ; row++)//行 { copyState[row] = state[row][col];//copy one col state h = (unsigned char)((signed char)state[row][col] >> 7);// state2[row] = state[row][col] << 1; state2[row] ^= 0x1b & h; } state[0][col] = state2[0] ^ copyState[3] ^ copyState[2] ^ state2[1] ^ copyState[1];/* 2 * a0 + a3 + a2 + 3 * a1 */ state[1][col] = state2[1] ^ copyState[0] ^ copyState[3] ^ state2[2] ^ copyState[2];/* 2 * a1 + a0 + a3 + 3 * a2 */ state[2][col] = state2[2] ^ copyState[1] ^ copyState[0] ^ state2[3] ^ copyState[3];/* 2 * a2 + a1 + a0 + 3 * a3 */ state[3][col] = state2[3] ^ copyState[2] ^ copyState[1] ^ state2[0] ^ copyState[0];/* 2 * a3 + a2 + a1 + 3 * a0 */ } } /* * 逆列处理 ????? */ void Aes::invMixColumns(unsigned char state[4][4]) { unsigned char state1[4];//2倍 unsigned char state2[4];//4倍 unsigned char state3[4];//8倍 unsigned char copyState[4];//1倍 unsigned char h; int col,row; for(col=0; col<4 ; col++){ for(row=0 ; row<4 ; row++){ copyState[row] = state[row][col]; h = (unsigned char)((signed char)state[row][col] >> 7);// state1[row] = state[row][col] << 1; state1[row] ^= 0x1b & h; h = (unsigned char)((signed char)state1[row] >> 7);// state2[row] = state1[row] << 1; state2[row] ^= 0x1b & h; h = (unsigned char)((signed char)state2[row] >> 7);// state3[row] = state2[row] << 1; state3[row] ^= 0x1b & h; } state[0][col] = (state3[0]^state2[0]^state1[0]) ^ (state3[3]^copyState[3]) ^ (state3[2]^state2[2]^copyState[2]) ^ (state3[1]^state1[1]^copyState[1]);/* 14 * a0 + 9 * a3 + 13 * a2 + 11 * a1 */ state[1][col] = (state3[1]^state2[1]^state1[1]) ^ (state3[0]^copyState[0]) ^ (state3[3]^state2[3]^copyState[3]) ^ (state3[2]^state1[2]^copyState[2]);/* 14 * a1 + 9 * a0 + 13 * a3 + 11 * a2 */ state[2][col] = (state3[2]^state2[2]^state1[2]) ^ (state3[1]^copyState[1]) ^ (state3[0]^state2[0]^copyState[0]) ^ (state3[3]^state1[3]^copyState[3]);/* 14 * a2 + 9 * a1 + 13 * a0 + 11 * a3 */ state[3][col] = (state3[3]^state2[3]^state1[3]) ^ (state3[2]^copyState[2]) ^ (state3[1]^state2[1]^copyState[1]) ^ (state3[0]^state1[0]^copyState[0]);/* 14 * a3 + 9 * a2 + 13 * a1 + 11 * a0 */ } }
至此最主要的4个操作已经解决，接下来就可以编写加密解密函数了，加密过程在一开始给的视频链接中有动态过程，这里就不啰嗦了。
附上完整代码：
main.cpp
#include <iostream> #include "Aes.h" #include <string> #include <stdlib.h> #include <fstream> #define FILEOPENERROR 1 using namespace std; int main() { int choose; bool glap = true; bool sign = true; Aes Encryption; Aes Decryption; while(glap) { choose = 0; cout<<"choose one option.\n"; cout<<"1. Aes Encryption\n" <<"2. Aes Decryption\n" <<"3. Quit\n"; cin>>choose; switch (choose) { case 1: Encryption.inputKey(); Encryption.setFilePath(); Encryption.initAes(); sign = true; do{ if(Encryption.encode() == FILEOPENERROR){ cout<<"file open fail, please input file path again!\n"; Encryption.setFilePath(); }else{//加密成功 cout<<"Encode success!\n"; sign = false; } }while(sign); cout<<endl<<endl; break; case 2: Decryption.inputKey(); Decryption.setFilePath(); Decryption.initAes(); sign = true; do{ if(Decryption.decode() == FILEOPENERROR){ cout<<"file open fail, please input file path again!\n"; Decryption.setFilePath(); }else{//解密成功 cout<<"Decode success!\n"; sign = false; } }while(sign); cout<<endl<<endl; break; case 3: glap = false; system("cls"); break; default: cout<<"option choose fail, choose again.\n"; cin>>choose; } } return 0; }
Aes.h
#ifndef AES_H #define AES_H #include <string.h> #include <fstream> using namespace std; class Aes { public: Aes(); virtual ~Aes(); void subBytes(unsigned char state[4][4]); void shiftRows(unsigned char state[4][4]); void mixColumns(unsigned char state[4][4]); void invSubBytes(unsigned char state[4][4]); void invShiftRows(unsigned char state[4][4]); void invMixColumns(unsigned char state[4][4]); void addRoundKey(unsigned char state[4][4], unsigned char roundKey[4][4]); void keySchedule(unsigned char roundKey[4][44]); void inputKey(); int encode(); int decode(); void setFilePath(); void setRoundKey(unsigned char* key) { for(int col=0 ; col<4 ; col++) for(int row=0 ; row<4 ; row++) roundKey_temp[row][col] = key[row+col*4]; } void initAes() { setRoundKey(initKey); keySchedule(roundKey_temp); for(int col=0 ; col<44 ; col++) for(int row=0 ; row<4 ; row++) roundKey[col/4][row][col%4] = roundKey_temp[row][col]; } private: char *filePath; unsigned char roundKey_temp[4][44]; unsigned char roundKey[11][4][4]; unsigned char initKey[16]; }; #endif // AES_H
Aes.cpp
#include "Aes.h" #include <iostream> #include <fstream> #include <string> #include <string.h> #define FILEOPENERROR 1 unsigned char s_box[256] = { /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 0x63,0x7c,0x77,0x7b,0xf2,0x6b,0x6f,0xc5,0x30,0x01,0x67,0x2b,0xfe,0xd7,0xab,0x76, /*0*/ 0xca,0x82,0xc9,0x7d,0xfa,0x59,0x47,0xf0,0xad,0xd4,0xa2,0xaf,0x9c,0xa4,0x72,0xc0, /*1*/ 0xb7,0xfd,0x93,0x26,0x36,0x3f,0xf7,0xcc,0x34,0xa5,0xe5,0xf1,0x71,0xd8,0x31,0x15, /*2*/ 0x04,0xc7,0x23,0xc3,0x18,0x96,0x05,0x9a,0x07,0x12,0x80,0xe2,0xeb,0x27,0xb2,0x75, /*3*/ 0x09,0x83,0x2c,0x1a,0x1b,0x6e,0x5a,0xa0,0x52,0x3b,0xd6,0xb3,0x29,0xe3,0x2f,0x84, /*4*/ 0x53,0xd1,0x00,0xed,0x20,0xfc,0xb1,0x5b,0x6a,0xcb,0xbe,0x39,0x4a,0x4c,0x58,0xcf, /*5*/ 0xd0,0xef,0xaa,0xfb,0x43,0x4d,0x33,0x85,0x45,0xf9,0x02,0x7f,0x50,0x3c,0x9f,0xa8, /*6*/ 0x51,0xa3,0x40,0x8f,0x92,0x9d,0x38,0xf5,0xbc,0xb6,0xda,0x21,0x10,0xff,0xf3,0xd2, /*7*/ 0xcd,0x0c,0x13,0xec,0x5f,0x97,0x44,0x17,0xc4,0xa7,0x7e,0x3d,0x64,0x5d,0x19,0x73, /*8*/ 0x60,0x81,0x4f,0xdc,0x22,0x2a,0x90,0x88,0x46,0xee,0xb8,0x14,0xde,0x5e,0x0b,0xdb, /*9*/ 0xe0,0x32,0x3a,0x0a,0x49,0x06,0x24,0x5c,0xc2,0xd3,0xac,0x62,0x91,0x95,0xe4,0x79, /*a*/ 0xe7,0xc8,0x37,0x6d,0x8d,0xd5,0x4e,0xa9,0x6c,0x56,0xf4,0xea,0x65,0x7a,0xae,0x08, /*b*/ 0xba,0x78,0x25,0x2e,0x1c,0xa6,0xb4,0xc6,0xe8,0xdd,0x74,0x1f,0x4b,0xbd,0x8b,0x8a, /*c*/ 0x70,0x3e,0xb5,0x66,0x48,0x03,0xf6,0x0e,0x61,0x35,0x57,0xb9,0x86,0xc1,0x1d,0x9e, /*d*/ 0xe1,0xf8,0x98,0x11,0x69,0xd9,0x8e,0x94,0x9b,0x1e,0x87,0xe9,0xce,0x55,0x28,0xdf, /*e*/ 0x8c,0xa1,0x89,0x0d,0xbf,0xe6,0x42,0x68,0x41,0x99,0x2d,0x0f,0xb0,0x54,0xbb,0x16 /*f*/ }; unsigned char Rcon[4][10] = { {0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x1b,0x36}, {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}, {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}, {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00} }; unsigned char Inv_S_Box[16][16] = { {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} }; using namespace std; Aes::Aes() { //ctor } Aes::~Aes() { //dtor } /* * 替换 already test */ void Aes::subBytes(unsigned char state[4][4]) { int x, y; int value; for(int i=0 ; i<4 ;i++){//列 for(int j=0 ; j<4 ;j++){//行 value = state[j][i]; x = value / 16 ; y = value % 16 ; state[j][i] = s_box[x*16+y]; } } } /* * 逆替换 already test */ void Aes::invSubBytes(unsigned char state[4][4]) { int col,row; int x,y; int value; for(col=0 ; col<4 ; col++){ for(row=0 ; row<4 ; row++){ value = state[row][col]; x = value / 16 ; y = value % 16 ; state[row][col] = Inv_S_Box[x][y]; } } } /* * 移动行 already test */ void Aes::shiftRows(unsigned char state[4][4]) { unsigned char temp; int times = 0; for(int i = 1; i < 4 ; i++)//行 { times = i; while(times--) { temp = state[i][0];//每一行的第一个元素 copy一份 for(int j = 1 ; j < 4 ; j++)//列 { state[i][j-1] = state[i][j]; //左移一位 } state[i][3] = temp;//填充最后一位 } } } /* * 逆移动行 already test */ void Aes::invShiftRows(unsigned char state[4][4]) { unsigned char temp; int times = 0; int i,j; for(i = 1; i < 4 ; i++)//行 { times = i; while(times--) { temp = state[i][3];//每一行的第一个元素 copy一份 for(j=2 ; j>=0 ; j--)//列 { state[i][j+1] = state[i][j]; //左移一位 } state[i][0] = temp;//填充最后一位 } } } /* * 列处理 already test */ void Aes::mixColumns(unsigned char state[4][4]) { unsigned char copyState[4]; unsigned char state2[4]; //2倍state unsigned char h; for(int col=0 ; col<4 ; col++)//列 { //每一列操作 for(int row=0 ; row<4 ; row++)//行 { copyState[row] = state[row][col];//copy one col state h = (unsigned char)((signed char)state[row][col] >> 7);// state2[row] = state[row][col] << 1; state2[row] ^= 0x1b & h; } state[0][col] = state2[0] ^ copyState[3] ^ copyState[2] ^ state2[1] ^ copyState[1];/* 2 * a0 + a3 + a2 + 3 * a1 */ state[1][col] = state2[1] ^ copyState[0] ^ copyState[3] ^ state2[2] ^ copyState[2];/* 2 * a1 + a0 + a3 + 3 * a2 */ state[2][col] = state2[2] ^ copyState[1] ^ copyState[0] ^ state2[3] ^ copyState[3];/* 2 * a2 + a1 + a0 + 3 * a3 */ state[3][col] = state2[3] ^ copyState[2] ^ copyState[1] ^ state2[0] ^ copyState[0];/* 2 * a3 + a2 + a1 + 3 * a0 */ } } /* * 逆列处理 ????? */ void Aes::invMixColumns(unsigned char state[4][4]) { unsigned char state1[4];//2倍 unsigned char state2[4];//4倍 unsigned char state3[4];//8倍 unsigned char copyState[4];//1倍 unsigned char h; int col,row; for(col=0; col<4 ; col++){ for(row=0 ; row<4 ; row++){ copyState[row] = state[row][col]; h = (unsigned char)((signed char)state[row][col] >> 7);// state1[row] = state[row][col] << 1; state1[row] ^= 0x1b & h; h = (unsigned char)((signed char)state1[row] >> 7);// state2[row] = state1[row] << 1; state2[row] ^= 0x1b & h; h = (unsigned char)((signed char)state2[row] >> 7);// state3[row] = state2[row] << 1; state3[row] ^= 0x1b & h; } state[0][col] = (state3[0]^state2[0]^state1[0]) ^ (state3[3]^copyState[3]) ^ (state3[2]^state2[2]^copyState[2]) ^ (state3[1]^state1[1]^copyState[1]);/* 14 * a0 + 9 * a3 + 13 * a2 + 11 * a1 */ state[1][col] = (state3[1]^state2[1]^state1[1]) ^ (state3[0]^copyState[0]) ^ (state3[3]^state2[3]^copyState[3]) ^ (state3[2]^state1[2]^copyState[2]);/* 14 * a1 + 9 * a0 + 13 * a3 + 11 * a2 */ state[2][col] = (state3[2]^state2[2]^state1[2]) ^ (state3[1]^copyState[1]) ^ (state3[0]^state2[0]^copyState[0]) ^ (state3[3]^state1[3]^copyState[3]);/* 14 * a2 + 9 * a1 + 13 * a0 + 11 * a3 */ state[3][col] = (state3[3]^state2[3]^state1[3]) ^ (state3[2]^copyState[2]) ^ (state3[1]^state2[1]^copyState[1]) ^ (state3[0]^state1[0]^copyState[0]);/* 14 * a3 + 9 * a2 + 13 * a1 + 11 * a0 */ } } /* * 异或处理 already test */ void Aes::addRoundKey(unsigned char state[4][4], unsigned char roundKey[4][4])// not test { for(int col=0 ; col<4 ; col++){ for(int row=0 ; row<4 ; row++){ state[row][col] ^= roundKey[row][col]; } } } /* * 轮密钥生成 already test */ void Aes::keySchedule(unsigned char roundKey[4][44]) { int colAfter=3; unsigned char subCol[4]; unsigned char downCol[4]; int x, y; int value; int t = 0;//轮数 为了使用Rcon for(int colBefore=0; colBefore<40 ; colBefore++){//当前轮的列 if((colAfter+1)%4 == 0){ //down one bite downCol[3] = roundKey[0][colAfter]; for(int row=1 ; row<4 ;row++){ downCol[row-1] = roundKey[row][colAfter]; } //sub bytes for(int i=0 ; i<4 ;i++){// value = downCol[i]; x = value / 16 ; y = value % 16 ; subCol[i] = s_box[x*16+y]; } //Xoring for(int j=0 ; j<4 ; j++){ roundKey[j][colAfter+1] = roundKey[j][colBefore] ^ subCol[j] ^ Rcon[j][t]; } t++; }else { //Xoring for(int j=0 ; j<4 ; j++){ roundKey[j][colAfter+1] = roundKey[j][colBefore] ^ roundKey[j][colAfter]; } } colAfter++; }//end for } /* * 加密 right */ int Aes::encode() { //打开文件 ifstream fileRd(filePath, ios::binary); ofstream fileWt("c:\\encode.txt", ios::binary); if(fileRd.fail() || fileWt.fail()){//打开失败 fileRd.close(); fileWt.close(); return FILEOPENERROR; } cout<<"your CIPHERTEXT file will be created at C:\\encode.txt!\n"; unsigned char buf[16];//取文件内容 unsigned char state[4][4];//运算状态 unsigned char enCdText[16];//加密后的数据 int t = 0; //计数器 int i,j; int col,row; bool glap = false; while(!fileRd.eof()) { glap = false; memset(buf,0x00,16*sizeof(char));//清空buf fileRd.read((char *)buf, sizeof(buf)); //cout<<buf<<endl; for(i=0 ; i<16 ; i++) if(buf[i] != 0x00){ glap = true; break; } if(!glap)break; //buf转化为state for(col=0 ; col<4 ; col++) for(row=0 ; row<4 ; row++) state[row][col] = buf[row+col*4]; //addRoundkey 第一轮 addRoundKey(state, roundKey[0]); //9轮 for(i=1 ; i<=9 ;i++){ subBytes(state); shiftRows(state); mixColumns(state); addRoundKey(state, roundKey[i]); } //最后一轮 subBytes(state); shiftRows(state); addRoundKey(state, roundKey[10]); //state 转化为 密文串 t = 0; for(i=0;i<4;i++){ for(j=0;j<4;j++){ enCdText[t++] = state[j][i]; } } for(i=0 ; i<16 ; i++) fileWt.put(enCdText[i]); } fileRd.close(); fileWt.close(); return 0; } /* * 解密 */ int Aes::decode() { //打开文件 ifstream fileRd("c:\\encode.txt", ios::binary); ofstream fileWt("c:\\decode.txt", ios::binary); if(fileRd.fail() || fileWt.fail()){//打开失败 fileRd.close(); fileWt.close(); return FILEOPENERROR; } cout<<"Your PLAINTEXT file will be created at C:\\decode.txt!\n"; unsigned char buf[16];//取文件内容 unsigned char state[4][4];//运算状态 unsigned char deCdText[16];//加密后的数据 int t = 0; //计数器 int i,j; int col,row; bool glap = false; while(!fileRd.eof()) { glap = false; memset(buf,0x00,16*sizeof(char));//清空buf fileRd.read((char *)buf, sizeof(buf)); //cout<<buf<<endl; for(i=0 ; i<16 ; i++) if(buf[i] != 0x00){ glap = true; break; } if(!glap)break; //buf转化为state for(col=0 ; col<4 ; col++) for(row=0 ; row<4 ; row++) state[row][col] = buf[row+col*4]; //addRoundkey 第一轮 addRoundKey(state, roundKey[10]); //9轮 for(i=9 ; i>=1 ;i--){ invShiftRows(state); invSubBytes(state); addRoundKey(state, roundKey[i]); invMixColumns(state); } //最后一轮 invShiftRows(state); invSubBytes(state); addRoundKey(state, roundKey[0]); //state 转化为 密文串 t = 0; for(i=0;i<4;i++){ for(j=0;j<4;j++){ deCdText[t++] = state[j][i]; } } for(i=0 ; i<16 ; i++) fileWt.put(deCdText[i]); } fileRd.close(); fileWt.close(); return 0; } void Aes::inputKey() { string temp_key; bool glap = true; int i; do{ cout<<"please input your key(16 characters) : "; cin>>temp_key; if(temp_key.length() == 16){ glap = false; cout<<"key init success!\n"; }else { glap = true; cout<<"key init fail, input again!\n"; } }while(glap); for(i=0 ; i<16 ; i++){ initKey[i] = temp_key[i]; } } void Aes::setFilePath() { char path[30]; cout<<"input your PLAINTEXT file path : "; cin>>path; int size = strlen(path); filePath = new char(size); strcpy(filePath, path); }
在写完程序后，需要对程序进行测试，可以在google上搜AES TEST VECTOR，这里我列出几个测试向量：
KEY = 8d2e60365f17c7df1040d7501b4a7b5a PLAINTEXT = 59b5088e6dadc3ad5f27a460872d5929 CIPHERTEXT = a02600ecb8ea77625bba6641ed5f5920 KEY = 2d0860dae7fdb0bd4bfab111f615227a PLAINTEXT = a02600ecb8ea77625bba6641ed5f5920 CIPHERTEXT = 5241ead9a89ca31a7147f53a5bf6d96a KEY = 7f498a034f6113a73abd442bade3fb10 PLAINTEXT = 5241ead9a89ca31a7147f53a5bf6d96a CIPHERTEXT = 22f09171bc67d0661d1c25f181a69f33