AES加密
DES加密的过程
具体的原理可以参考：
DES实现
文章给出了AES加密算法的一个实现。未做任何优化，仅供学习参考，计算速度跟专业的库相比应该有很大差距。虽然密码学算法是安全的，但是工程实现中可能存在其他攻击，没有足够的信心，不要使用自己写的加密算法做加密。
import java.math.BigInteger;
import java.util.Random;
/**
* @author miracle
* @date 2022/11/14 22:12
* @description: <br/>
*/
public class Main {
/**
* 将一个十进制的数字转化为指定进制，指定位数的数字符串（位数不够，前面补零）
* 如：
* - 将 33 转化为长度为 8 的二进制字符串
* - 则结果为： "00100001"
*
* @param number 带转换的十进制数字
* @param radix 将要转化为的进制数
* @param length 转化后字符串的长度
* @return 满足要求的字符串
*/
public static String toString(int number, int radix, int length) {
StringBuilder str = new StringBuilder();
for (int i = 0; i < length; i++) {
int bit = number % radix;
str.insert(0, bit);
number = number / radix;
}
return str.toString();
}
// --------------------------------------------------- 常量定义 -------------------------------------------------------------------
// S盒
private static int[][] SBox = new int[][]{
{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}
};
// 列混合左乘的矩阵
private static int[][] mixCol = {
{2, 3, 1, 1},//
{1, 2, 3, 1},//
{1, 1, 2, 3},//
{3, 1, 1, 2}
};
// 密钥扩展算法中的轮常量
private static int[][] RC = new int[][]{
{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}
};
private static int[][] InvMixCol = {
{0x0e, 0x0b, 0x0d, 0x09},//
{0x09, 0x0e, 0x0b, 0x0d},//
{0x0d, 0x09, 0x0e, 0x0b},//
{0x0b, 0x0d, 0x09, 0x0e}
};
// 逆 S 盒
private static int[][] InvSBox = new int[][]{
{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}
};
// --------------------------------------------------- 工具函数 -------------------------------------------------------------------
// 工具函数，将int类型的二维数组以十六进制显示，用来查看数据的正确性
private static void showByHex(int[][] a) {
int i = 0;
System.out.println("[");
for (int[] rows : a) {
i = 0;
System.out.print("[");
for (int row : rows) {
if (i < 4) {
String toHexString = Integer.toHexString(row);
if (toHexString.length() == 1) {
toHexString = "0" + toHexString;
}
System.out.print(toHexString + ",");
i++;
} else {
i = 0;
String toHexString = Integer.toHexString(row);
if (toHexString.length() == 1) {
toHexString = "0" + toHexString;
}
System.out.print(toHexString + ",");
i++;
}
}
System.out.println("]");
}
System.out.println("]");
}
// --------------------------------------------------- 加密算法 -------------------------------------------------------------------
// ------------------------------ 格式化工具 ----------------------------------
/**
* 将给定二进制明文转换为4*4的矩阵，矩阵中的元素按照列优先的顺序排列
*
* @param plaintext 长度位128bit的明文数据，或者密钥数据
* @return 将128bit的数据平均分成16份，按照列优先的顺序存储到一个4*4的矩阵中返回。
*/
private static int[][] getMatrix(String plaintext) {
int[][] res = new int[4][4];
for (int i = 0; i < plaintext.length(); ) {
StringBuilder bytes = new StringBuilder();
for (int j = 0; j < 8; j++) {
bytes.append(plaintext.charAt(i++));
}
int row = ((i - 1) / 8) % 4;
int col = ((i - 1) / 32) % 4;
res[row][col] = Integer.parseInt(bytes.toString(), 2);
}
return res;
}
/**
* 将明文转化的矩阵还原为明文，是getMatrix()函数的逆过程
*
* @param matrix 明文转化的矩阵
* @return 还原的矩阵
*/
private static String matrixToString(int[][] matrix) {
StringBuilder builder = new StringBuilder();
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
builder.append(toString(matrix[j][i], 2, 8));
}
}
return builder.toString();
}
// ------------------------------ 主要加密过程 ----------------------------------
/**
* 初始变换
* 将明文对应的矩阵和密钥转化的矩阵取异或（混淆）
*
* @return 返回异或的结果
*/
private static int[][] InitialRound(String plaintext, String key) {
int[][] res = new int[4][4];
// 将明文和密钥化为矩阵
int[][] p = getMatrix(plaintext);
int[][] k = getMatrix(key);
// 将明文矩阵和密钥矩阵按列异或
res = xor(p, k);
return res;
}
// 按列异或
private static int[][] xor(int[][] a, int[][] b) {
int[][] res = new int[4][4];
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
res[j][i] = a[j][i] ^ b[j][i];
}
}
return res;
}
/**
* 前九轮加密
* 加密算法的核心，每次需要四个步骤
* 1. 字节代换
* 2. 行移位
* 3. 列混合
* 4. 轮密钥加
*
* @param initialRound 明文经过初始变换后的到的密文
* @param subKeys 一个密钥和十个子密钥
* @return 明文九轮变换后的密文
*/
private static int[][] FirstNineRounds(int[][] initialRound, int[][][] subKeys) {
//
for (int i = 1; i <= 9; i++) {
int[][] subBytes = SubBytes(initialRound);
int[][] shiftRows = ShiftRows(subBytes);
int[][] mixColumns = MixColumns(shiftRows);
initialRound = AddRoundKey(mixColumns, subKeys[i]);
}
return initialRound;
}
/**
* 最后一轮加密
* 与前九轮加密相比，少了列混合这一步
*
* @param initialRound 明文经过初始变换后的到的密文
* @param subKeys 一个密钥和十个子密钥
* @return 第十轮加密后的密文，即最终密文
*/
private static int[][] LastRound(int[][] initialRound, int[][][] subKeys) {
int[][] subBytes = SubBytes(initialRound);
int[][] shiftRows = ShiftRows(subBytes);
initialRound = AddRoundKey(shiftRows, subKeys[10]);
return initialRound;
}
// ------------------------------ 十轮加密的细节 ----------------------------------
/**
* 字节代换
* 由于明文矩阵中每个元素由2个十六进制的数字表示，以高位上的十六进制数字位行号，低位上的十六进制数字位列号，查询S盒
* 将S盒中对应位置的元素作为 字节代换后的元素。将整个矩阵都进行该代换即可得到字节代换后的密文矩阵
*
* @param initialRound 待加密矩阵
* @return 待加密矩阵经过字节代换后得到的矩阵
*/
private static int[][] SubBytes(int[][] initialRound) {
int[][] res = new int[4][4];
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
// 获取 行列索引
int row = initialRound[j][i] >>> 4 & 0b1111;
int col = initialRound[j][i] & 0b1111;
res[j][i] = SBox[row][col];
}
}
return res;
}
/**
* 行移位
* 对于字节代换后的矩阵，将其第i行的元素循环左移i位（i = 0,1,2,3）
*
* @return 移位后的矩阵
*/
private static int[][] ShiftRows(int[][] subBytes) {
for (int i = 1; i < 4; i++) {
subBytes[i] = leftMove(subBytes[i], i);
}
return subBytes;
}
// 反转指定位置的字符串
private static int[] reverseStr(int[] arr, int start, int end) {
while (start < end) {
int temp = arr[start];
arr[start] = arr[end];
arr[end] = temp;
start++;
end--;
}
return arr;
}
// 将字符串向左循环移动 n 位
private static int[] leftMove(int[] arr, int n) {
arr = reverseStr(arr, 0, n - 1);
arr = reverseStr(arr, n, arr.length - 1);
return reverseStr(arr, 0, arr.length - 1);
}
/**
* 列混合
* 将行移位后的矩阵左乘一个给定的矩阵 mixCol 这里的乘法是定义在 优先于GF(2^8)上的乘法
*
* @param ShiftRows 行移位后的矩阵
* @return 列混合后的矩阵
*/
private static int[][] MixColumns(int[][] ShiftRows) {
int[][] res = new int[4][4];
int i, j, k;
for (i = 0; i < 4; i++) {
for (j = 0; j < 4; j++) {
for (k = 0; k < 4; k++) {
res[i][j] ^= Multiple(mixCol[i][k], ShiftRows[k][j]);
}
}
}
return res;
}
// 有限域 GF(2^8) 上的乘法
private static int Multiple(int a, int b) {
int[] multiplier = new int[8];
// 获取乘数
multiplier[0] = a;
int prior = a;
for (int i = 1; i < 8; i++) {
multiplier[i] = prior & 0b1111111;
multiplier[i] <<= 1;
if ((prior >>> 7 & 1) == 1) {
multiplier[i] ^= 0b00011011;
}
prior = multiplier[i];
}
int res = 0;
for (int i = 0; i < 8; i++) {
if ((b & 1) == 1) {
res = res ^ multiplier[i];
}
b >>>= 1;
}
return res;
}
/**
* 轮密钥加
* 将列混合后的矩阵与对应的子密钥按列进行异或
*
* @param mixColumns 列混合后的矩阵
* @param subKey 本轮加密对应的子密钥
* @return 轮密钥加后的矩阵
*/
private static int[][] AddRoundKey(int[][] mixColumns, int[][] subKey) {
int[][] res = new int[4][4];
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
res[i][j] = mixColumns[i][j] ^ subKey[i][j];
}
}
return res;
}
// --------------------------------------------------- 密钥扩展算法 ---------------------------------------------------------------------
/**
* 密钥扩展算法
* 通过给定的16个字节密钥，生成一个176字节的轮密钥，里面包括原密钥和其生成的十个子密钥（每个子密钥都是16个字节）
*
* @param key 密钥
* @return 子密钥集合
*/
private static int[][][] getSubKeys(int[][] key) {
int[][][] subKeys = new int[11][4][4];
// 分别获取十个子密钥
int[][] W = new int[4][44];
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
W[i][j] = key[i][j];
}
}
int round = 0;
for (int i = 4; i < 44; i++) {
if (i % 4 != 0) {
for (int j = 0; j < 4; j++) {
W[j][i] = W[j][i - 4] ^ W[j][i - 1];
}
} else {
int[] Wi = new int[]{W[0][i - 1], W[1][i - 1], W[2][i - 1], W[3][i - 1]};
int[] T = T(Wi, round++);
for (int j = 0; j < 4; j++) {
W[j][i] = W[j][i - 4] ^ T[j];
}
}
}
// 密钥何其生成的十个子密钥
for (int k = 0; k < 11; k++) {
for (int i = 0; i < 4; i++) {
for (int j = k * 4; j < k * 4 + 4; j++) {
subKeys[k][i][j % 4] = W[i][j];
}
}
}
return subKeys;
}
/**
* T函数
* 当i是四的倍数时，用来处理W[i-1]，以增加密码的安全性
*
* @param Wi 待处理的列向量，该向量的i是四的倍数
* @param round AES一共要进行十轮的加密，round记录现在是第几轮加密（round从1开始）
* @return 处理后的列向量
*/
private static int[] T(int[] Wi, int round) {
int[] wordCycle = wordCycle(Wi);
int[] sBoxReplace = SBoxReplace(wordCycle);
return roundConstantXOR(sBoxReplace, round);
}
// T函数 ----- 字循环
private static int[] wordCycle(int[] Wi) {
return leftMove(Wi, 1);
}
// T函数 ----- SBox代换
private static int[] SBoxReplace(int[] wordCycle) {
for (int i = 0; i < 4; i++) {
// 获取 行列索引
int row = wordCycle[i] >>> 4 & 0b1111;
int col = wordCycle[i] & 0b1111;
wordCycle[i] = SBox[row][col];
}
return wordCycle;
}
// T函数 ----- 轮常量异或
private static int[] roundConstantXOR(int[] SBoxReplace, int round) {
for (int i = 0; i < 4; i++) {
SBoxReplace[i] ^= RC[i][round];
}
return SBoxReplace;
}
// --------------------------------------------------- 解密算法 -------------------------------------------------------------------
private static int[][] InvInitialRound(String ciphertext, int[][] key) {
int[][] res;
// 将明文和密钥化为矩阵
int[][] c = getMatrix(ciphertext);
// 将明文矩阵和密钥矩阵按列异或
res = xor(c, key);
return res;
}
private static int[][] InvFirstNineRounds(int[][] initialRound, int[][][] subKeys) {
//
for (int i = 1; i <= 9; i++) {
int[][] invShiftRows = InvShiftRows(initialRound);
int[][] invSubBytes = InvSubBytes(invShiftRows);
int[][] invAddRoundKey = InvAddRoundKey(invSubBytes, subKeys[10 - i]);
initialRound = InvMixColumns(invAddRoundKey);
}
return initialRound;
}
private static int[][] InvShiftRows(int[][] initialRound) {
for (int i = 1; i < 4; i++) {
initialRound[i] = leftMove(initialRound[i], 4 - i);
}
return initialRound;
}
private static int[][] InvSubBytes(int[][] invShiftRows) {
int[][] res = new int[4][4];
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
// 获取 行列索引
int row = invShiftRows[j][i] >>> 4 & 0b1111;
int col = invShiftRows[j][i] & 0b1111;
res[j][i] = InvSBox[row][col];
}
}
return res;
}
private static int[][] InvAddRoundKey(int[][] mixColumns, int[][] subKey) {
int[][] res = new int[4][4];
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
res[i][j] = mixColumns[i][j] ^ subKey[i][j];
}
}
return res;
}
private static int[][] InvMixColumns(int[][] invAddRoundKey) {
int[][] res = new int[4][4];
int i, j, k;
for (i = 0; i < 4; i++) {
for (j = 0; j < 4; j++) {
for (k = 0; k < 4; k++) {
res[i][j] ^= Multiple(InvMixCol[i][k], invAddRoundKey[k][j]);
}
}
}
return res;
}
private static int[][] InvLastRound(int[][] initialRound, int[][][] subKeys) {
int[][] invShiftRows = InvShiftRows(initialRound);
int[][] invSubBytes = InvSubBytes(invShiftRows);
initialRound = InvAddRoundKey(invSubBytes, subKeys[0]);
return initialRound;
}
// --------------------------------------------------- 128bit加密解密 -------------------------------------------------------------------
/**
* 加密核心算法(一次加密128bit数据)
*
* @param plaintext 明文转化的二进制组成的字符串。
* @param key 密钥转化的以二进制表示的字符串
* @return 128bit明文加密得到的密文
*/
private static String encryptCore(String plaintext, String key) {
// 1. 初始变换
int[][] initialRound = InitialRound(plaintext, key);
// 2. 获取子密钥
int[][][] subKeys = getSubKeys(getMatrix(key));
// 3. 前九轮变换
int[][] firstNineRounds = FirstNineRounds(initialRound, subKeys);
// 4. 第十轮变换
int[][] lastRound = LastRound(firstNineRounds, subKeys);
// 5. 将密文矩阵转为加密后的二进制字符串返回
return matrixToString(lastRound);
}
/**
* 解密核心算法（一次解密128bit）
*
* @param ciphertext 密文
* @return 加密后的明文
*/
private static String decryptCore(String ciphertext, String key) {
// 1. 获取密钥
int[][][] subKeys = getSubKeys(getMatrix(key));
// 2. 轮密钥加
int[][] invInitialRound = InvInitialRound(ciphertext, subKeys[10]);
// 3. 逆九轮循环
int[][] invFirstNineRounds = InvFirstNineRounds(invInitialRound, subKeys);
// 4. 逆最后一轮
int[][] invLastRound = InvLastRound(invFirstNineRounds, subKeys);
// 5. 将密文转化为明文字符串
return matrixToString(invLastRound);
}
// --------------------------------------------------- 任意字符串加密解密 -------------------------------------------------------------------
/**
* 加密任意长度的字符串
*
* @param plaintext 明文，可以是任意字符串
* @param key 密钥，128bit的二进制组成的字符串
* @return plaintext经过密钥key加密后的密文
*/
private static String encrypt(String plaintext, String key) {
byte[] bytes = plaintext.getBytes();
int remainder = bytes.length % 16;
StringBuilder res = new StringBuilder();
if (remainder != 0) {
// 先将前面被十六整除的字节加密
for (int i = 0; i < bytes.length - remainder; ) {
StringBuilder p = new StringBuilder();
for (int j = 0; j < 16; j++) {
p.append(toString(bytes[i++], 2, 8));
}
String c = encryptCore(p.toString(), key);
res.append(c);
}
// 剩下的字节不够16个，用 "$" 即 36 填充到 16 个，并加密
StringBuilder temp = new StringBuilder();
for (int i = bytes.length - remainder; i < bytes.length; i++) {
temp.append(toString(bytes[i], 2, 8));
}
for (int i = 0; i < 16 - remainder; i++) {
temp.append(toString(36, 2, 8));
}
String c = encryptCore(temp.toString(), key);
res.append(c);
} else {
for (int i = 0; i < bytes.length; ) {
StringBuilder p = new StringBuilder();
for (int j = 0; j < 16; j++) {
p.append(toString(bytes[i++], 2, 8));
}
String c = encryptCore(p.toString(), key);
res.append(c);
}
}
return res.toString();
}
/**
* 解密密文，将其恢复为明文
*
* @param ciphertext 密文
* @param key 密钥
* @return 明文
*/
private static String decrypt(String ciphertext, String key) {
StringBuilder res = new StringBuilder();
for (int i = 0; i < ciphertext.length(); ) {
StringBuilder c = new StringBuilder();
for (int j = 0; j < 128; j++) {
c.append(ciphertext.charAt(i++));
}
String p = decryptCore(c.toString(), key);
String string = binaryToString(p);
res.append(string);
}
return res.toString();
}
/**
* 佛南工具函数，将二进制数字转化为字符串
*
* @param binary 用字符串转化的二进制
* @return 二进制转换为的字符串
*/
private static String binaryToString(String binary) {
int i = 0;
int len = binary.length();
byte[] bytes = new byte[16];
int idx = 0;
while (i < len) {
StringBuilder builder = new StringBuilder();
boolean isPositve = true;
isPositve = binary.charAt(i++) == 1 ? false : true;
for (int j = 0; j < 7; j++) {
builder.append(binary.charAt(i++));
}
if (isPositve) {
bytes[idx++] = Byte.parseByte(builder.toString(), 2);
} else {
bytes[idx++] = Byte.parseByte("-" + builder.toString(), 2);
}
}
return new String(bytes);
}
// --------------------------------------------------- 测试函数 -------------------------------------------------------------------
private static void testFunctions() {
// int[][] matrix = getMatrix("00000001" + "00100011" + "01010001" + "01100111" + "10001001" + "10101011" + "11001101" + "11101111" + "00000001" + "00100011" + "01000101" + "01100111" + "10001001" + "10101011" + "11001101" + "11101111");
// showByHex(matrix);
// String string = matrixToString(matrix);
// System.out.println(string);
// int[][] key = getMatrix("00000011" + "00100111" + "01010001" + "01100111" + "10001001" + "10101011" + "11001101" + "11101111" + "00000001" + "00100011" + "01000101" + "01100111" + "10001001" + "10101011" + "11001101" + "11101111");
// showByHex(key);
// int[][] xor = xor(matrix,key);
// showByHex(xor);
// System.out.println();
// showByHex(SBox);
// int[][] subBytes = SubBytes(matrix);
// showByHex(subBytes);
// int[][] shiftRows = ShiftRows(subBytes);
// showByHex(shiftRows);
// int[][] invshiftRows = InvShiftRows(subBytes);
// showByHex(invshiftRows);
// int[][] addRoundKey = AddRoundKey(matrix,subBytes);
// showByHex(matrix);
// showByHex(subBytes);
// showByHex(addRoundKey);
// // System.out.println(Multiple(0b01101011,0b10001101));
// // System.out.println(MyTools.toString(184,2,8));
// int[][] col = new int[][]{
// {0xd4,0xe0,0xb8,0x1e},{0xbf,0xb4,0x41,0x27},{0x5d,0x52,0x11,0x98},{0x30,0xae,0xf1,0xe5}
// };
// int[][] mixColumns = MixColumns(col);
// showByHex(mixColumns);
// int[] wordCycle = wordCycle(new int[]{1,2,3,4});
// for(int i : wordCycle){
// System.out.print(i + ",");
// }
// System.out.println();
// int[] sBoxReplace = SBoxReplace(wordCycle);
// for(int i : sBoxReplace){
// System.out.print(Integer.toBinaryString(i) + ",");
// }
// System.out.println();
// int[] roundConstantXOR = roundConstantXOR(sBoxReplace,0);
// for(int i : roundConstantXOR){
// System.out.print(Integer.toBinaryString(i) + ",");
// }
// int[][] key = new int[][]{
// {0x2b,0x28,0xab,0x09},//
// {0x7e,0xae,0xf7,0xcf},//
// {0x15,0xd2,0x15,0x4f},//
// {0x16,0xa6,0x88,0x3c}
// };
// int[][][] subKeys = getSubKeys(key);
// for(int i = 0; i < subKeys.length; i++){
// showByHex(subKeys[i]);
// }
// int[] pArr = new int[]{0x32,0x43,0xf6,0xa8,0x88,0x5a,0x30,0x8d,0x31,0x31,0x98,0xa2,0xe0,0x37,0x07,0x34};
// StringBuilder p = new StringBuilder();
// for(int item : pArr){
// p.append(MyTools.toString(item,2,8));
// }
// int[] cArr = new int[]{0x2b,0x7e,0x15,0x16,0x28,0xae,0xd2,0xa6,0xab,0xf7,0x15,0x88,0x09,0xcf,0x4f,0x3c};
// StringBuilder c = new StringBuilder();
// for(int item : cArr){
// c.append(MyTools.toString(item,2,8));
// }
// String ciphertext = encryptCore(p.toString(),c.toString());
// System.out.println(ciphertext);
// showByHex(getMatrix(ciphertext));
// String plaintext = decryptCore(ciphertext,c.toString());
// System.out.println(plaintext);
// showByHex(getMatrix(plaintext));
// System.out.println("---------------------------------------------------------");
}
public static void main(String[] args) {
// testFunctions();
String plain = "0123456789 AES I love you!";
String key = "10101110110110111010111011011011101011101101101110101110110110111010111011011011101011101101101110101110110110111010111011011011";
String cipher = encrypt(plain, key);
System.out.println("密文为：\n" + cipher);
plain = decrypt(cipher, key);
System.out.println("明文为：\n" + plain);
System.out.println("注意，解密过程中，最后一部分不足16byte，末尾补$");
}
}