AES加密算法实验报告.docx

1、AES加密算法实验报告四 川 大 学 计 算 机 学 院、软 件 学 院实 验 报 告 学号：姓名：专业： 班级： 第 10 周课程名称 密码学与网络安全实验课时2实验项目AES加密算法实验时间实验目的 完成AES加密算法，实现图片加密与解密，并将加密后的结果以图片格式保存。实验环境 PC机，Windows7操作系统，Visual C+ 实验内容（算法、程序、步骤和方法） 一、简介美国国家标准技术研究所在2001年发布了高级加密标准（AES）。AES是一个对称加密算法，旨在取代DES成为广泛使用的标准。AES中的所有运算都是在8为的字节上运行的。特别饿，加减乘除算术都是在有限域GF(28)上运

2、行的。二、程序特点本次试验中要求对图片进行加密与解密，并将加密结果以图片格式进行保存。因此为了实现对图片的调度及保存，使用头文件进行对图片的操作，实现对图片的像素读取，图片的保存。在程序运行读取需要加密的图片时，需要进行图片的选取，本次实验中使用在弹窗中选取文件的方式，使用头文件来实现在文件夹中选择需要的文件的选取。三、加密算法流程AES加密算法流程如下字节代替：用一个S盒完成分组的字节到字节的代替；行移位：进行一次行上的置换；列混合：利用有限域GF(28)上的运算特性的一个代替；轮密钥加：当前分组和扩展密钥的一部分进行按位异或。四、代码实现#include #include class pl

3、aintextpublic: plaintext(); static void createplaintext(unsigned char a); static void SubBytes(unsigned char p16); static void inSubBytes(unsigned char p16); static void ShiftRows(unsigned char e); static void inShiftRows(unsigned char e); static void MatrixToByte(unsigned char e); static void inMat

4、rixToByte(unsigned char e); static unsigned char FFmul(unsigned char a, unsigned char b); static void KeyAdding(unsigned char state16, unsigned char k4); static void KeyExpansion(unsigned char* key, unsigned char w44); plaintext();private:;#include using namespace std;static unsigned char sBox = ;/定

5、义加密S盒/unsigned char insBox256 =;/定义解密S盒plaintext:plaintext()void plaintext:createplaintext(unsigned char a)/创建明文 int i = 0; unsigned int p16; for (int j = 0; j200; j+) if (aj = 0) break; for (; i16; i+) pi = ai; ai = ai + 16; void plaintext:SubBytes(unsigned char p16)/字节变换函数 unsigned char b16; for (

6、int i = 0; i16; i+) bi = sBox(int)pi; void plaintext:inSubBytes(unsigned char p16)/逆字节变换函数 unsigned char b16; for (int i = 0; i16; i+) bi = insBox(int)pi; void plaintext:ShiftRows(unsigned char e)/行移位变换函数 unsigned char t4; for (int i = 1; i4; i+) for (int x = 0; x4; x+) tx = ex + i * 4; for (int y =

7、 0; y4; y+) e(y + 4 - i) % 4 + i * 4 = ty; void plaintext:inShiftRows(unsigned char e)/逆行移位变换函数 unsigned char t4; for (int i = 1; i4; i+) for (int x = 0; x4; x+) tx = ex + i * 4; for (int y = 0; y4; y+) e(y + i) % 4 + i * 4 = ty; void plaintext:MatrixToByte(unsigned char e)/列混合变换函数 unsigned char t4;

8、 int r, c; for (c = 0; c 4; c+) for (r = 0; r4; r+) tr = er * 4 + c; for (r = 0; r4; r+) er * 4 + c = FFmul(0x02, tr) FFmul(0x03, t(r + 1) % 4) FFmul(0x01, t(r + 2) % 4) FFmul(0x01, t(r + 3) % 4); void plaintext:inMatrixToByte(unsigned char e)/逆列混合变换函数 unsigned char t4; int r, c; for (c = 0; c 4; c+

9、) for (r = 0; r4; r+) tr = er * 4 + c; for (r = 0; r4; r+) er * 4 + c = FFmul(0x0e, tr) FFmul(0x0b, t(r + 1) % 4) FFmul(0x0d, t(r + 2) % 4) FFmul(0x09, t(r + 3) % 4); unsigned char plaintext:FFmul(unsigned char a, unsigned char b) unsigned char bw4; unsigned char res = 0; int i; bw0 = b; for (i = 1;

10、 i4; i+) bwi = bwi - 1 1; if (bwi - 1 & 0x80) bwi = 0x1b; for (i = 0; i i) & 0x01) res = bwi; return res;void plaintext:KeyAdding(unsigned char state16, unsigned char k4)/轮密钥加 int r, c; for (c = 0; c4; c+) for (r = 0; r4; r+) stater + c * 4 = krc; void plaintext:KeyExpansion(unsigned char* key, unsi

11、gned char w44)/密钥扩展 int i, j, r, c; unsigned char rc = 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 ; for (r = 0; r4; r+) for (c = 0; c4; c+) w0rc = keyr + c * 4; for (i = 1; i = 10; i+) for (j = 0; j4; j+) unsigned char t4; for (r = 0; r4; r+) tr = j wirj - 1 : wi - 1r3; if (j = 0) un

12、signed char temp = t0; for (r = 0; r3; r+) tr = sBoxt(r + 1) % 4; t3 = sBoxtemp; t0 = rci - 1; for (r = 0; r4; r+) wirj = wi - 1rj tr; plaintext:plaintext()#include#include#include/使用文件选取功能#include using namespace std;unsigned char w1144 = 0 ;int len = 0;/图片每行需要加密的长度void Cipher();/加密图片void inCipher(

13、);/解密图片void Cipher(unsigned char a) unsigned char b16; for (int i = 0; i (len / 16); i+) for (int j = 0; j16; j+) bj = aj + i * 16; plaintext:KeyAdding(b, w0); for (int n = 1; n = 10; n+) plaintext:SubBytes(b); plaintext:ShiftRows(b); if (n != 10)plaintext:MatrixToByte(b); plaintext:KeyAdding(b, wn)

14、; for (int m = 0; m16; m+) am + i * 16 = bm; void inCipher(unsigned char a) unsigned char b16; for (int i = 0; i (len / 16) ; i+) for (int j = 0; j= 0; n-) plaintext:inShiftRows(b); plaintext:inSubBytes(b); plaintext:KeyAdding(b, wn); if (n)plaintext:inMatrixToByte(b); for (int m = 0; m16; m+) am +

15、i * 16 = bm; bool ImageCopy(const CImage &srcImage, CImage &destImage) int i, j;/循环变量 if () return FALSE; /源图像参数 BYTE* srcPtr = (BYTE*)(); int srcBitsCount = (); int srcWidth = (); int srcHeight = (); int srcPitch = (); /销毁原有图像 if (!() (); /创建新图像 if (srcBitsCount = 32) /支持alpha通道 (srcWidth, srcHeigh

16、t, srcBitsCount, 1); else (srcWidth, srcHeight, srcBitsCount, 0); BYTE *destPtr = (BYTE*)(); int destPitch = (); len=abs(srcPitch); for (int i = 0; isrcHeight; i+) Cipher(srcPtr + i*srcPitch); /复制图像数据 for (i = 0; isrcHeight; i+) memcpy(destPtr + i*destPitch, srcPtr + i*srcPitch, abs(srcPitch); retur

17、n TRUE;bool inImageCopy(const CImage &srcImage, CImage &destImage) int i, j;/循环变量 if () return FALSE; /源图像参数 BYTE* srcPtr = (BYTE*)(); int srcBitsCount = (); int srcWidth = (); int srcHeight = (); int srcPitch = (); /销毁原有图像 if (!() (); /创建新图像 if (srcBitsCount = 32) /支持alpha通道 (srcWidth, srcHeight, s

18、rcBitsCount, 1); else (srcWidth, srcHeight, srcBitsCount, 0); BYTE *destPtr = (BYTE*)(); int destPitch = (); len = abs(srcPitch); for (int i = 0; isrcHeight; i+) inCipher(srcPtr + i*srcPitch); /复制图像数据 for (i = 0; isrcHeight; i+) memcpy(destPtr + i*destPitch, srcPtr + i*srcPitch, abs(srcPitch); retur

19、n TRUE;int main() unsigned char key16 = /固定密钥 0x77, 0x59, 0xc5, 0xa4, 0x55, 0x90, 0xa4, 0xa3, 0xb2, 0xcc, 0x01, 0xa9, 0xcb, 0xac, 0x77, 0x23 ; plaintext:KeyExpansion(key, w); TCHAR szBufferMAX_PATH = 0 ;/使用文件选取功能 OPENFILENAME ofn = 0 ; = sizeof(ofn); / = m_hWnd; = _T();/要选择的文件后缀 = _T(D:);/默认的文件路径 =

20、szBuffer;/存放文件的缓冲区 = sizeof(szBuffer) / sizeof(*szBuffer); = 0; = OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST | OFN_EXPLORER;/标志如果是多选要加上OFN_ALLOWMULTISELECT BOOL bSel = GetOpenFileName(&ofn); CImage image, image2, image3;/读取图片 (szBuffer); ImageCopy(image, image2); (e:/); inImageCopy(image2, image3); (e:/); system(pause);本数据记录和计算 运行程序，出现选择图片界面加密结束原图片 加密图片 解密图片 结 论（结 果） 根据结果显示，程序成功的实现了对图片的加密，得到的加密后的结果仍然为图片，并成功地的解密得到了正确的解密后的图片。小 结 通过本次试验，成功的完成了对AES密码算法的初步编写，了解了AES算法的工作原理。对于图片加密方面，掌握了新的调用图片的方法 ，使用头文件大大简化了c+中对图片调用的难度。同时在文件读取方面使用了头文件，使得程序在使用上更加方便。指导老师评 议 成绩评定： 指导教师签名：