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对称密码体制

云南大学数学与统计学实验教学中心实验报告一、实验目的:通过实验掌握AES加密实验的构造算法,以及其重要思想。

二、实验内容:查阅资料,实现AES密码体制的编码算法、译码算法、子密钥生成算法三、实验环境Win7、Eclipse四、实验过程(请学生认真填写):实验过程、结果以及相应的解释:1. 预备知识密码学中的高级加密标准(Advanced Encryption Standard,AES),是一种对称加密的方法。

本实验使用Java平台来编写的,虽然在java中已经很好的实现了AES等安全机制,但是为了了解如何实现,还是写了一个AES加密的java程序。

2. 实验过程A、原理分析:大多数AES计算是在一个特别的有限域完成的。

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金钥(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列的四个字节。

最后一个加密循环中省略MixColumns步骤,而以另一个AddRoundKey取代。

B、具体代码如下://如6.2,若是将每一行看做是一个对象的话//具体实现的整体结构思想如此下图结果如下://得到结果与真实结果一样。

说明正确具体代码如下:由于所写代码过多,所以,本代码附在最后!五、实验总结1.遇到的问题及分析:遇到问题:其实这次编写程序遇到的问题还是蛮多的!例如S盒子的生成、逆S盒子的生成,算法中的每一步轮转,密钥生成,密钥长度等都遇到了问题。

由于时间仓促,这里就不一一举出来了。

分析并解决:-通过图书馆查询相应资料以及课本查阅得到了一些解决。

同时在网上查找到了一使用C++编写的程序代码以及算法理论。

得到了解决。

2.体会和收获。

编程实现了AES,个人感觉AEs实现起来还是比较困难的(对于我来说)因为他中间的矩阵操作复杂。

当然收获就是能有一定能力来编写这样的一个程序了。

六、参考文献计算机网络课本。

七、教师评语:附录:AES代码*************************Aes.java***************************** package AES;/*** AES字节数组加密算法类*/public class Aes {private int Nb;// 以32位为单位的字长private int Nk;// 以32位为单位的密钥长度private int Nr;// 轮数private byte[] key;// 密钥private byte[][] Sbox;// S盒矩阵private byte[][] iSbox;// s盒逆矩阵private byte[][] w;// 密钥调度表private byte[][] Rcon;// 轮常数表private byte[][] State;// 状态矩阵/*** 构造方法* @param keySize* @param keyBytes*/public Aes(int keySize, byte[] keyBytes, int Nb) { SetNbNkNr(keySize, Nb);this.key = new byte[this.Nk * 4];this.key = keyBytes;BuildSbox();BuildInvSbox();BuildRcon();KeyExpansion();}/*** 生成Rcon轮常数矩阵*/private void BuildRcon() {this.Rcon = new byte[100][4];Rcon[0][0] = 0x00;// Rcon[1][0]=0x01;for (int i = 1; i < 100; i++) {Rcon[i][0] = gfmultby02(Rcon[i - 1][0]);}}/*** 设置Nb,Nk,Nr* @param keysize*/private void SetNbNkNr(int keysize, int Nb) { this.Nb = Nb;switch (keysize) {case KEYSIZE.Bit128:this.Nk = 4;this.Nr = 10;break;case KEYSIZE.Bit192:this.Nk = 6;this.Nr = 12;break;case KEYSIZE.Bit256:this.Nk = 8;this.Nr = 14;break;}}/*** 生成S盒矩阵*/private void BuildSbox() {this.Sbox = new byte[][] {/* 0 1 2 3 4 5 6 7 8 9 a b c d e f *//* 0 */{ 0x63, 0x7c, 0x77, 0x7b, (byte) 0xf2, 0x6b, 0x6f,(byte) 0xc5, 0x30, 0x01, 0x67, 0x2b, (byte) 0xfe,(byte) 0xd7, (byte) 0xab, 0x76 },/* 1 */{ (byte) 0xca, (byte) 0x82, (byte) 0xc9, 0x7d,(byte) 0xfa, 0x59, 0x47, (byte) 0xf0, (byte) 0xad,(byte) 0xd4, (byte) 0xa2, (byte) 0xaf, (byte) 0x9c,(byte) 0xa4, 0x72, (byte) 0xc0 },/* 2 */{ (byte) 0xb7, (byte) 0xfd, (byte) 0x93, 0x26, 0x36,0x3f, (byte) 0xf7, (byte) 0xcc, 0x34, (byte) 0xa5,(byte) 0xe5, (byte) 0xf1, 0x71, (byte) 0xd8, 0x31, 0x15 }, /* 3 */{ 0x04, (byte) 0xc7, 0x23, (byte) 0xc3, 0x18,(byte) 0x96, 0x05, (byte) 0x9a, 0x07, 0x12,(byte) 0x80, (byte) 0xe2, (byte) 0xeb, 0x27,(byte) 0xb2, 0x75 },/* 4 */{ 0x09, (byte) 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a,(byte) 0xa0, 0x52, 0x3b, (byte) 0xd6, (byte) 0xb3,0x29, (byte) 0xe3, 0x2f, (byte) 0x84 },/* 5 */{ 0x53, (byte) 0xd1, 0x00, (byte) 0xed, 0x20,(byte) 0xfc, (byte) 0xb1, 0x5b, 0x6a, (byte) 0xcb,(byte) 0xbe, 0x39, 0x4a, 0x4c, 0x58, (byte) 0xcf }, /* 6 */{ (byte) 0xd0, (byte) 0xef, (byte) 0xaa, (byte) 0xfb,0x43, 0x4d, 0x33, (byte) 0x85, 0x45, (byte) 0xf9, 0x02,0x7f, 0x50, 0x3c, (byte) 0x9f, (byte) 0xa8 },/* 7 */{ 0x51, (byte) 0xa3, 0x40, (byte) 0x8f, (byte) 0x92,(byte) 0x9d, 0x38, (byte) 0xf5, (byte) 0xbc,(byte) 0xb6, (byte) 0xda, 0x21, 0x10, (byte) 0xff,(byte) 0xf3, (byte) 0xd2 },/* 8 */{ (byte) 0xcd, 0x0c, 0x13, (byte) 0xec, 0x5f,(byte) 0x97, 0x44, 0x17, (byte) 0xc4, (byte) 0xa7,0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73 },/* 9 */{ 0x60, (byte) 0x81, 0x4f, (byte) 0xdc, 0x22, 0x2a,(byte) 0x90, (byte) 0x88, 0x46, (byte) 0xee,(byte) 0xb8, 0x14, (byte) 0xde, 0x5e, 0x0b, (byte) 0xdb }, /* a */{ (byte) 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,(byte) 0xc2, (byte) 0xd3, (byte) 0xac, 0x62,(byte) 0x91, (byte) 0x95, (byte) 0xe4, 0x79 },/* b */{ (byte) 0xe7, (byte) 0xc8, 0x37, 0x6d, (byte) 0x8d,(byte) 0xd5, 0x4e, (byte) 0xa9, 0x6c, 0x56,(byte) 0xf4, (byte) 0xea, 0x65, 0x7a, (byte) 0xae, 0x08 }, /* c */{ (byte) 0xba, 0x78, 0x25, 0x2e, 0x1c, (byte) 0xa6,(byte) 0xb4, (byte) 0xc6, (byte) 0xe8, (byte) 0xdd,0x74, 0x1f, 0x4b, (byte) 0xbd, (byte) 0x8b, (byte) 0x8a }, /* d */{ 0x70, 0x3e, (byte) 0xb5, 0x66, 0x48, 0x03,(byte) 0xf6, 0x0e, 0x61, 0x35, 0x57, (byte) 0xb9,(byte) 0x86, (byte) 0xc1, 0x1d, (byte) 0x9e },/* e */{ (byte) 0xe1, (byte) 0xf8, (byte) 0x98, 0x11, 0x69,(byte) 0xd9, (byte) 0x8e, (byte) 0x94, (byte) 0x9b,0x1e, (byte) 0x87, (byte) 0xe9, (byte) 0xce, 0x55,0x28, (byte) 0xdf },/* f */{ (byte) 0x8c, (byte) 0xa1, (byte) 0x89, 0x0d,(byte) 0xbf, (byte) 0xe6, 0x42, 0x68, 0x41,(byte) 0x99, 0x2d, 0x0f, (byte) 0xb0, 0x54,(byte) 0xbb, 0x16 } };}/*** 生成逆s盒矩阵*/private void BuildInvSbox() {int x, y;this.iSbox = new byte[16][16];for (int i = 0; i < 16; i++) {for (int j = 0; j < 16; j++) {x = (int) ((this.Sbox[i][j] >> 4) & 0x0f);y = (int) (this.Sbox[i][j] & 0x0f);this.iSbox[x][y] = (byte) (16 * i + j);}}}/*** 扩展密钥*/private void KeyExpansion() {this.w = new byte[Nb * (Nr + 1)][4];for (int row = 0; row < Nk; ++row) {this.w[row][0] = this.key[4 * row];this.w[row][1] = this.key[4 * row + 1];this.w[row][2] = this.key[4 * row + 2];this.w[row][3] = this.key[4 * row + 3];}byte[] temp = new byte[Nb];for (int row = Nk; row < Nb * (Nr + 1); ++row) {temp[0] = this.w[row - 1][0];temp[1] = this.w[row - 1][1];temp[2] = this.w[row - 1][2];temp[3] = this.w[row - 1][3];if (row % Nk == 0) {temp = SubWord(RotWord(temp));temp[0] = (byte) (temp[0] ^ this.Rcon[row / Nk][0]);temp[1] = (byte) (temp[1] ^ this.Rcon[row / Nk][1]);temp[2] = (byte) (temp[2] ^ this.Rcon[row / Nk][2]);temp[3] = (byte) (temp[3] ^ this.Rcon[row / Nk][3]);} else if (Nk > 6 && (row % Nk == 4)) {temp = SubWord(temp);}this.w[row][0] = (byte) (this.w[row - Nk][0] ^ temp[0]);this.w[row][1] = (byte) (this.w[row - Nk][1] ^ temp[1]);this.w[row][2] = (byte) (this.w[row - Nk][2] ^ temp[2]);this.w[row][3] = (byte) (this.w[row - Nk][3] ^ temp[3]);}}/*** SubWord方法* @param subWord* @return*/private byte[] SubWord(byte[] subWord) {for (int c = 0; c < subWord.length; ++c) {subWord[c] = this.Sbox[(subWord[c] >> 4) & 0x0f][(subWord[c] & 0x0f)];}return subWord;}/*** RotWord方法* @param rotWord* @return*/private byte[] RotWord(byte[] rotWord) {byte[] temp = rotWord;byte[] b = new byte[4];for (int i = 0; i < 4; i++) {b[i] = temp[(i + 1) % 4];}return b;}/*** 轮密钥加* @param round*/private void AddRoundKey(int round) {for (int r = 0; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {this.State[r][c] = (byte) (this.State[r][c] ^ w[(round * Nb)+ c][r]);}}}/*** SubBytes方法*/private void SubBytes() {for (int r = 0; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {this.State[r][c] = this.Sbox[(this.State[r][c] >> 4) &0x0f][(this.State[r][c] & 0x0f)];}}}/*** InvSubBytes方法*/private void InvSubBytes() {for (int r = 0; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {this.State[r][c] = this.iSbox[(this.State[r][c] >> 4) &0x0f][(this.State[r][c] & 0x0f)];}}}/*** 行移位*/private void ShiftRows() {byte[][] temp = new byte[4][Nb];for (int r = 0; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {temp[r][c] = this.State[r][c];}}for (int r = 1; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {this.State[r][c] = temp[r][(c + r) % Nb];}}}/*** 逆行移位*/private void InvShiftRows() {byte[][] temp = new byte[4][Nb];for (int r = 0; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {temp[r][c] = this.State[r][c];}}for (int r = 1; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {this.State[r][c] = temp[r][(c - r + Nb) % Nb];}}}/*** 列混合*/private void MixColumns() {byte[][] temp = new byte[4][Nb];for (int r = 0; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {temp[r][c] = this.State[r][c];}}for (int c = 0; c < Nb; ++c) {this.State[0][c] = (byte) (gfmultby02(temp[0][c])^ gfmultby03(temp[1][c]) ^ gfmultby01(temp[2][c]) ^gfmultby01(temp[3][c]));this.State[1][c] = (byte) (gfmultby01(temp[0][c])^ gfmultby02(temp[1][c]) ^ gfmultby03(temp[2][c]) ^gfmultby01(temp[3][c]));this.State[2][c] = (byte) (gfmultby01(temp[0][c]) ^ (gfmultby01(temp[1][c]) ^ gfmultby02(temp[2][c]) ^ gfmultby03(temp[3][c])));this.State[3][c] = (byte) (gfmultby03(temp[0][c])^ gfmultby01(temp[1][c]) ^ (gfmultby01(temp[2][c]) ^gfmultby02(temp[3][c])));}}/*** 逆列混合*/private void InvMixColumns() {byte[][] temp = new byte[4][Nb];for (int r = 0; r < 4; ++r) {for (int c = 0; c < Nb; ++c) {temp[r][c] = this.State[r][c];}}for (int c = 0; c < Nb; c++) {this.State[0][c] = (byte) (gfmultby0e(temp[0][c])^ gfmultby0b(temp[1][c]) ^ gfmultby0d(temp[2][c]) ^gfmultby09(temp[3][c]));this.State[1][c] = (byte) (gfmultby09(temp[0][c])^ gfmultby0e(temp[1][c]) ^ gfmultby0b(temp[2][c]) ^gfmultby0d(temp[3][c]));this.State[2][c] = (byte) (gfmultby0d(temp[0][c]) ^ (gfmultby09(temp[1][c]) ^ gfmultby0e(temp[2][c]) ^ gfmultby0b(temp[3][c])));this.State[3][c] = (byte) (gfmultby0b(temp[0][c])^ gfmultby0d(temp[1][c]) ^ (gfmultby09(temp[2][c]) ^gfmultby0e(temp[3][c])));}}// 有限域GF(28)部分变换private byte gfmultby01(byte b) {return b;}private byte gfmultby02(byte b) {if (((b >> 7) & 0x01) == 0) // !!!!!!!这里比较大小的时候注意符号位return (byte) (b << 1);elsereturn (byte) ((b << 1) ^ (byte) 0x1b);}private byte gfmultby03(byte b) {return (byte) (gfmultby02(b) ^ gfmultby01(b));}private byte gfmultby09(byte b) {return (byte) (gfmultby02(gfmultby02(gfmultby02(b))) ^ gfmultby01(b));}private byte gfmultby0b(byte b) {return (byte) (gfmultby02(gfmultby02(gfmultby02(b))) ^ gfmultby02(b) ^gfmultby01(b));}private byte gfmultby0d(byte b) {return (byte) (gfmultby02(gfmultby02(gfmultby02(b)))^ gfmultby02(gfmultby02(b)) ^ gfmultby01(b));}private byte gfmultby0e(byte b) {return (byte) (gfmultby02(gfmultby02(gfmultby02(b)))^ gfmultby02(gfmultby02(b)) ^ gfmultby02(b));}/*** 加密过程* @param input* @param output*/public void Cipher(byte[] input, byte[] output) {this.State = new byte[4][Nb];for (int i = 0; i < (4 * Nb); i++) {this.State[i / Nb][i % Nb] = input[i];}// 初始化状态矩阵AddRoundKey(0);// 轮密钥加for (int round = 1; round < Nr; ++round) {SubBytes();// S盒变换ShiftRows();// 行移位MixColumns();// 列混合AddRoundKey(round);}SubBytes();// S盒置换ShiftRows();// 行移位AddRoundKey(Nr);// 轮密钥加for (int i = 0; i < (4 * Nb); i++) {output[i] = this.State[i / Nb][i % Nb];}}/*** 解密过程* @param inputs* @param output*/public void Invcipher(byte[] input, byte[] output) {this.State = new byte[4][Nb];for (int i = 0; i < (4 * Nb); ++i) {this.State[i / Nb][i % Nb] = input[i];}// 初始化状态矩阵AddRoundKey(Nr);// 轮密钥加for (int round = Nr - 1; round > 0; round--) {InvShiftRows();// 逆行移位InvSubBytes();// 逆S盒置换AddRoundKey(round);// 轮密钥加InvMixColumns();// 逆列混合}InvShiftRows();// 逆行移位InvSubBytes();// 逆S盒置换AddRoundKey(0);// 轮密钥加for (int i = 0; i < (4 * Nb); ++i) {output[i] = this.State[i / Nb][i % Nb];}// 输出结果}}*************************AesCipherAndInvCipher.java**************** package AES;import java.io.UnsupportedEncodingException;import java.security.InvalidKeyException;/*** 辅助类处理明文字符输入字节数不匹配等问题*/public class AesCipherAndInvCipher {byte[] key;// 密钥private byte[] pt;// 明文字节数组private byte[] ct;private int mode;private int Nb = 0;private int dataLength;private int blockSize = 4;// 分组大小32位,4bytespublic AesCipherAndInvCipher(byte[] kb) {this.key = kb;}/*** 加密* @param kb* @param plainText* @return加密后密文字节数组*/private byte[] Eecrypt(String plainText, byte[] kb)throws InvalidKeyException {try {pt = plainText.getBytes("UTF-8");// 获取明文字节数组} catch (UnsupportedEncodingException e) {System.out.println("不支持的编码类型!");e.printStackTrace();}dataLength = pt.length;mode = dataLength % blockSize;// 判断明文数组长度是否与分组长度匹配ct = new byte[mode == 0 ? pt.length : dataLength / blockSize * 4 + 32];// 密文字节数组Nb = dataLength / blockSize;Aes a1 = new Aes(KEYSIZE.Bit128, kb, Nb);Aes a2 = new Aes(KEYSIZE.Bit128, kb, 4);Aes a3 = new Aes(KEYSIZE.Bit128, kb, 4);if (mode == 0) {a1.Cipher(pt, ct);} else {byte[] b1 = new byte[blockSize * Nb];// 匹配的部分byte[] b2 = new byte[16];// 剩余部分byte[] b3 = new byte[16];// 存明文长度byte[] c1 = new byte[b1.length];byte[] c2 = new byte[b2.length];byte[] c3 = new byte[b3.length];System.arraycopy(pt, 0, b1, 0, b1.length);System.arraycopy(pt, Nb * blockSize, b2, 0, mode);b3 = intToByteArray(dataLength);a1.Cipher(b1, c1);a2.Cipher(b2, c2);a3.Cipher(b3, c3);System.arraycopy(c1, 0, ct, 0, c1.length);System.arraycopy(c2, 0, ct, b1.length, c2.length);System.arraycopy(c3, 0, ct, b1.length + b2.length, c3.length);}return ct;}public byte[] EecryptToBytes(String plainText, byte[] kb)throws InvalidKeyException {byte[] ct = Eecrypt(plainText, kb);return ct;}public String EecryptToString(String plainText, byte[] kb)throws InvalidKeyException {byte[] ct = Eecrypt(plainText, kb);return BytesToString(ct);}/*** 解密*/public String Decrypt(byte[] ct, byte[] kb) {String s = "";if (mode == 0) {byte[] output = new byte[dataLength];Aes a = new Aes(KEYSIZE.Bit128, kb, Nb);a.Invcipher(ct, output);try {s = new String(output, "UTF-8");System.out.println("解密:" + s);} catch (UnsupportedEncodingException e) {System.out.println("不支持的编码格式!");e.printStackTrace();}} else {byte[] length = new byte[16];byte[] plainText1 = new byte[ct.length - 32];byte[] plainText2 = new byte[16];Aes a1 = new Aes(KEYSIZE.Bit128, kb, Nb);Aes a2 = new Aes(KEYSIZE.Bit128, kb, 4);Aes a3 = new Aes(KEYSIZE.Bit128, kb, 4);byte[] c1 = new byte[ct.length - 32];byte[] c2 = new byte[16];byte[] c3 = new byte[16];System.arraycopy(ct, ct.length - 16, c3, 0, c3.length);System.arraycopy(ct, ct.length - 32, c2, 0, c2.length);System.arraycopy(ct, 0, c1, 0, Nb * blockSize);a3.Invcipher(c3, length);// 解密明文字节数组长度a2.Invcipher(c2, plainText2);// 解密剩余的部分a1.Invcipher(c1, plainText1);// 解密匹配的部分int length1 = byteArrayToInt(length);byte[] output = new byte[length1];System.arraycopy(plainText1, 0, output, 0, plainText1.length);System.arraycopy(plainText2, 0, output, plainText1.length, length1 - plainText1.length);try {s = new String(output, "UTF-8");System.out.println("解密后明文:" + s);} catch (UnsupportedEncodingException e) {System.out.println("不支持的编码格式!");e.printStackTrace();}}return s;}public String Decrypt(String cryptText, byte[] kb) {byte[] ct = StringToBytes(cryptText);return Decrypt(ct, kb);}public String Decrypt(Byte[] ct, byte[] kb) {return Decrypt(ct, kb);}/*** int转化为Byte数组** @param value* @return*/private static byte[] intToByteArray(int value) {byte[] b = new byte[16];for (int i = 0; i < 4; i++) {int offset = (b.length - 1 - i) * 8;b[i] = (byte) ((value >>> offset) & 0xFF);}for (int i = 4; i < 16; i++) {b[i] = 0;}return b;}/*** byte数组转化为int** @param b* @return*/private static final int byteArrayToInt(byte[] b) {byte[] b1 = new byte[4];System.arraycopy(b, 0, b1, 0, 4);return (b1[0] << 24) + ((b1[1] & 0xFF) << 16) + ((b1[2] & 0xFF) << 8) + (b1[3] & 0xFF);}/*** 显示字节数组** @param b*/public static void DisplayAsBytes(byte[] b) {for (int i = 0; i < b.length; i++) {String hex = Integer.toHexString(b[i] & 0xFF);if (hex.length() == 1) {hex = '0' + hex;}System.out.print(hex.toUpperCase() + " ");}System.out.println();}private static String BytesToString(byte[] b) {String s = "";for (int i = 0; i < b.length; i++) {String hex = Integer.toHexString(b[i] & 0xFF);if (hex.length() == 1) {hex = '0' + hex;}s += hex;}return s;}private static byte[] StringToBytes(String cryptText) { byte[] b = new byte[cryptText.length() / 2];int[] a = new int[cryptText.length()];for (int i = 0; i < cryptText.length(); ++i) {String s = cryptText.substring(i, i + 1);if (s.equals("a"))a[i] = 10;else if (s.equals("b"))a[i] = 11;else if (s.equals("c"))a[i] = 12;else if (s.equals("d"))a[i] = 13;else if (s.equals("e"))a[i] = 14;else if (s.equals("f"))a[i] = 15;elsea[i] = Integer.valueOf(s);}for (int i = 0; i < cryptText.length() / 2; i++) {b[i] = (byte) (a[2 * i] * 16 + a[2 * i + 1]);}return b;}}*************************generateKey.java********************** package AES;import java.io.UnsupportedEncodingException;import java.security.InvalidKeyException;import java.util.Random;public class generateKey {private static byte[] key;/*** 随机生成key* @param keySize* @return* @throws InvalidKeyException*/public static byte[] generateRandomKey(int keySize)throws InvalidKeyException {if (keySize == KEYSIZE.Bit128 | keySize == KEYSIZE.Bit192| keySize == KEYSIZE.Bit256) {key = new byte[keySize / 8];for (int i = 0; i < keySize / 8; i++) {Random r = new Random();int tempByte = r.nextInt() * 255;key[i] = (byte) tempByte;}return key;} else {throw new InvalidKeyException("密钥长度错误,正确长度为128,192或者256位!");}}/*** 根据字符串生成key* @param keyStr* @return*/public static byte[] generateKeyFromString(String keyStr) {byte[] tempkey = null;try {tempkey = keyStr.getBytes("UTF-8");} catch (UnsupportedEncodingException e) {System.out.println("不支持的编码类型!");e.printStackTrace();}if (tempkey.length < 128) {key = new byte[16];byte lastByte = tempkey[tempkey.length - 1];for (int i = tempkey.length; i < 16; i++) {key[i] = gfmultby02(lastByte);lastByte = key[i - 1];}} else if (tempkey.length > 128 && tempkey.length < 192) {key = new byte[24];byte lastByte = tempkey[tempkey.length - 1];for (int i = tempkey.length; i < 24; i++) {key[i] = gfmultby02(lastByte);lastByte = key[i - 1];}} else if (tempkey.length > 192 && tempkey.length < 256) {key = new byte[32];byte lastByte = tempkey[tempkey.length - 1];for (int i = tempkey.length; i < 32; i++) {key[i] = gfmultby02(lastByte);lastByte = key[i - 1];}} else if (tempkey.length > 256) {key = new byte[32];System.arraycopy(tempkey, 0, key, 0, 32);} else {key = tempkey;}return key;}public int getKeyLength() {return key.length;}private static byte gfmultby02(byte b) {if (((b >> 7) & 0x01) == 0) // !!!!!!!这里比较大小的时候注意符号位return (byte) (b << 1);elsereturn (byte) ((b << 1) ^ (byte) 0x1b);// 消除符号位可以用b&0xff}}*************************KEYSIZE.java*************************package AES;/*** 密钥长度** @author卢富毓*/public class KEYSIZE {public static final int Bit128 = 128;// 128位public static final int Bit192 = 192;// 192位public static final int Bit256 = 256;// 256位}*************************testAes.java*************************package AES;import java.security.InvalidKeyException;public class testAes {public static void main(String[] args) {byte[] plainText = new byte[] { 0x11, 0x11, 0x22, 0x33, 0x44, 0x55,0x66, 0x77, (byte) 0x88, (byte) 0x99, (byte) 0xaa, (byte) 0xbb,(byte) 0xcc, (byte) 0xdd, (byte) 0xee, (byte) 0xff, 0x00, 0x11,// 0x22,// 0x33,0x44,// 0x55,0x66, 0x77 };// 明文byte[] cipherText = new byte[20];byte[] decipheredText = new byte[20];byte[] keyBytes = null;try {keyBytes = generateKey.generateKeyFromString("AES1wrwe2432v112wwwwwwwwwwwwwwwwwwww@@@@@@@@@@@@@@@@@@@@@@@@ @@@@@@@@@@@@@@@@@@@@@@@@@wwwwwwwwwwwwwwwwwwwwwww34@#%$1234fffffffffffffffffffffff");} catch (Exception e1) {// TODO Auto-generated catch blocke1.printStackTrace();}Aes a = new Aes(KEYSIZE.Bit192, keyBytes, 5);System.out.println("***********************测试1****************************");byte[] key1 = null;try {key1 = generateKey.generateRandomKey(KEYSIZE.Bit128);} catch (InvalidKeyException e1) {e1.printStackTrace();}AesCipherAndInvCipher aes = new AesCipherAndInvCipher(key1);byte[] dt = null;String ss = null;try {dt = new byte[16];dt = aes.EecryptToBytes("AES11212121212121", keyBytes);ss = aes.EecryptToString("AES1wrwe2432v1343", keyBytes);System.out.println("明文1:AES11212121212121");System.out.println("明文2:AES1wrwe2432v1343");System.out.println("字节式加密,密文:" + new String(dt));System.out.println("字符串式加密,密文:" + ss);} catch (InvalidKeyException e) {e.printStackTrace();}aes.Decrypt(dt, keyBytes);aes.Decrypt(ss, keyBytes);System.out.println("\n*************************测试2*****************************");AesCipherAndInvCipher aes1 = new AesCipherAndInvCipher(key1);byte[] dt1 = null;try {// dt = new byte[16];String plainText1 = "uuid=FSFASW24S-0342-FEW3-3F33-F44F2SE523432D";dt1 = aes1.EecryptToBytes(plainText1, keyBytes);System.out.println("明文:" + plainText1);System.out.println("字节式加密,密文:" + new String(dt1));} catch (InvalidKeyException e) {e.printStackTrace();}aes1.Decrypt(dt1, keyBytes);}/*** 显示16进制* @param b*/public static void DisplayAsBytes(byte[] b) {for (int i = 0; i < b.length; i++) {String hex = Integer.toHexString(b[i] & 0xFF);if (hex.length() == 1) {hex = '0' + hex;}System.out.print(hex.toUpperCase() + " ");}System.out.println();}}。

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