rijndael.java

ECLIPSE 3.3工程. AES算法的应用.

/*
 * 所有的字符串作为输入时.
 * ***********************************************************
 * 在加密和解密的初始阶段，输入数组 in 按照下述规则复制到状态矩阵中： s[r,c]=in[r+4c]
 * for 0 ≤ r < 4 且 0 ≤ c < Nb
 * 在加密和解密的结束阶段，状态矩阵将按照下述规则被复制到输出数组 out 中： out[r+4c]=
 * s[r,c] for 0 ≤ r < 4 且 0 ≤ c < Nb
 */
public class Rijndael {
  /* 状态包含的列(32-bit 字)的个数。对于AES，分组输入为128bit时,Nb＝4 */
  private final int Nb = 4;
  private String input = "";
  private String state = "";

  public Rijndael() {
  }
  public Rijndael(String state) {
    this.state = state;
    this.input = state;
  }
  /**
   * 字节变换,将一串输入通过SBox变换输出.
   * @param input
   *          type : 16Byte String .
   * @return state .type : 16Byte String .
   */
  public String subBytes(String input) {
    Operator op = new Operator();
    this.state = subBytes(op.ToByte(input));
    return this.state;
  }
  public String invSubBytes(String input) {
    Operator op = new Operator();
    this.state = invSubBytes(op.ToByte(input));
    return this.state;
  }
  public String invSubBytes(byte[] input) {
    SBox sBox = new SBox();
    int length = input.length;
    String Tstate = "";
    for (int i = 0; i < length; i++) {
      Tstate += (char) sBox.invSubByte((byte) input[i]);
    }
    return Tstate;
  }
  /**
   * 字节变换,将一串输入通过SBox变换输出.
   * @param input
   *          type : Byte[16]
   * @return state .type : 16Byte String .
   */
  public String subBytes(byte[] input) {
    SBox sBox = new SBox();
    int length = input.length;
    String Tstate = "";
    for (int i = 0; i < length; i++) {
      Tstate += (char) sBox.subByte((byte) input[i]);
    }
    return Tstate;
  }
  /**
   * 行移位.将16个字符看成4个字节为一列顺序,组成的4*4的矩阵. *
   * 将输入的矩阵的每行按行号(from 0)大小进行循环左移.
   * @param input
   * @return state .type : 16Byte String .
   */
  public String shiftRows(String input) {
    this.state = "";
    byte[][] inputMatrix = new byte[4][Nb];
    byte[][] stateMatrix = new byte[4][Nb];
    stringToMatrix(input, inputMatrix);// 将字符串的输入,放入一个矩阵.
    /*
     * 先按行操作.对输入矩阵进行操作,并复制给状态矩阵.****************
     * 将行中的4个字节,按行号(from 0)大小进行循环左移
     */
    for (int r = 0; r < 4; r++) {
      // 行序
      for (int c = 0; c < Nb; c++) {
        // 列序
        stateMatrix[r][c] = inputMatrix[r][(c + r) % Nb];
      }
    }
    matrixToString(stateMatrix);// 将状态矩阵输入到字符串.
    /*
     * 置空,让JRE自动处理内存. inputMatrix = null; stateMatrix =
     * null;
     */
    return this.state;
  }
  /**
   * 逆算行移位.将16个字符看成4个字节为一列顺序,组成的4*4的矩阵. *
   * 将输入的矩阵的每行按行号(from 3 to 0)大小进行循环右移.
   * @param input
   * @return state .type : 16Byte String .
   */
  public String invShiftRows(String input) {
    this.state = "";
    byte[][] inputMatrix = new byte[4][Nb];
    byte[][] stateMatrix = new byte[4][Nb];
    stringToMatrix(input, inputMatrix);// 将字符串的输入,放入一个矩阵.
    /*
     * 先按行操作.对输入矩阵进行操作,并复制给状态矩阵.****************
     * 将行中的4个字节,按行号(from 3 to 0)大小进行循环右移
     */
    for (int r = 0; r < 4; r++) {
      // 行序
      for (int c = 0; c < Nb; c++) {
        // 列序
        stateMatrix[r][c] = inputMatrix[r][(c - (r + 1) + Nb) % Nb];
      }
    }
    matrixToString(stateMatrix);// 将状态矩阵输入到字符串.
    /*
     * 置空,让JRE自动处理内存. inputMatrix = null; stateMatrix =
     * null;
     */
    return this.state;
  }
  /**
   * 将状态矩阵输入到字符串.以每列为单位.
   * @param matrix
   */
  private void matrixToString(byte[][] matrix) {
    /* 先按列操作. 将状态矩阵的元素赋给字符串. */
    for (int c = 0; c < Nb; c++) {
      // 列序
      for (int r = 0; r < 4; r++) {
        // 行序
        this.state += (char) matrix[r][c];
      }
    }
  }
  /**
   * 将字符串的输入,放入一个矩阵. 每4字节为单位先按每列进行放.
   * @param input
   * @param matrix
   */
  private void stringToMatrix(String input, byte[][] matrix) {
    /* 按每列操作. 将字符串放放输入矩阵 */
    for (int c = 0; c < Nb; c++) {
      // 列序
      for (int r = 0; r < 4; r++) {
        // 行序
        matrix[r][c] = (byte) input.charAt(r + c * 4);
      }
    }
  }
  /**
   * 列混合.Hex {03,01,01,02}在行上按行号+1,即(1~4)循环右移.***
   * 相乘,按GF(2^8次)Mod.得到状态矩阵.***********************
   * GF(8)=x^8+ x^4+x^3+x^1+1,Binary : 1 0001 1011.*
   * GF(8)= 11B(16进制.).
   * @param input
   *          type : String
   * @return state .type : 16Byte String .
   */
  public String mixColumns(String input) {
    this.state = "";
    byte[][] aMatrix = new byte[4][4];// AES中定义的a(x).
    byte[] temp = { (byte) 0x03, (byte) 0x01, (byte) 0x01, (byte) 0x02 };
    /*
     * 循环右移. 移位个数:1~4 , 赋给a(x)
     */
    for (int r = 0; r < 4; r++) {
      // 行序
      for (int c = 0; c < Nb; c++) {
        // 列序
        aMatrix[r][c] = temp[(c - (r + 1) + Nb) % Nb];
        // System.out.print((byte)aMatrix[r][c] + " ");
      }
      // System.out.println();
    }
    byte[][] inputMatrix = new byte[4][Nb];
    stringToMatrix(input, inputMatrix);// 赋给状态矩阵
    Operator op = new Operator();
    byte[][] stateMatrix = new byte[4][Nb];
    for (int r = 0; r < Nb; r++) {
      for (int m = 0; m < 4; m++) {
        for (int q = 0; q < 4; q++) {
          stateMatrix[m][r] ^=
            op.mulByTwoPolynomials(aMatrix[m][q], inputMatrix[q][r]);
        }
      }
    }
    this.matrixToString(stateMatrix);// 将矩阵赋给字符串.
    return this.state;
  }
  /**
   * 逆算列混合.Hex
   * {0x0b,0x0d,0x09,0x0e}在行上按行号+1,即(1~4)循环右移.
   * 相乘,按GF(2^8次)Mod.得到状态矩阵.***********************
   * GF(8)=x^8+ x^4+x^3+x^1+1,Binary : 1 0001 1011.*
   * GF(8)= 11B(16进制.).
   * @param input
   *          type : String
   * @return state .type : 16Byte String .
   */
  public String invMixColumns(String input) {
    this.state = "";
    byte[][] aMatrix = new byte[4][4];// AES中定义的a(x).
    byte[] temp = { (byte) 0x0b, (byte) 0x0d, (byte) 0x09, (byte) 0x0e };
    /*
     * 循环右移. 移位个数:1~4 , 赋给a(x)
     */
    for (int r = 0; r < 4; r++) {
      // 行序
      for (int c = 0; c < Nb; c++) {
        // 列序
        aMatrix[r][c] = temp[(c - (r + 1) + Nb) % Nb];
        // System.out.print((byte)aMatrix[r][c] + " ");
      }
      // System.out.println();
    }
    byte[][] inputMatrix = new byte[4][Nb];
    stringToMatrix(input, inputMatrix);// 赋给状态矩阵
    Operator g = new Operator();
    byte[][] stateMatrix = new byte[4][Nb];
    for (int r = 0; r < Nb; r++) {
      for (int m = 0; m < 4; m++) {
        for (int q = 0; q < 4; q++) {
          stateMatrix[m][r] ^=
            g.mulByTwoPolynomials(aMatrix[m][q], inputMatrix[q][r]);
        }
      }
    }
    this.matrixToString(stateMatrix);// 将矩阵赋给字符串.
    return this.state;
  }
  /**
   * 加入轮密钥.
   * @param input
   *          type : String
   * @return state .type : 16Byte String .
   */
  public String addRoundKey(String input, String key) {
    String mw = "";
    Operator g = new Operator();
    int keyc = key.length() / 4;
    byte[][] w = new byte[keyc][4];
    byte[][] k = new byte[keyc][4];
    g.ToByte(w, input);
    g.ToByte(k, key);
    for (int i = 0; i < keyc; i++) {
      w[i] = g.XOR(w[i], k[i]);
      mw += g.ToString(w[i]);
    }
    // System.out.println(mw);
    return mw;
  }
  /**
   * rijndael算法.合并了四步.
   * @param input
   * @return state .type : 16Byte String .
   */
  public String rijndael(String input, String key) {
    this.state = addRoundKey(input, key);
    Key K = new Key();
    for (int i = 1; i <= 10; i++) {
      key = K.SKey(key, i);
      this.state = subBytes(this.state);
      this.state = shiftRows(this.state);
      if (i < 10) {
        this.state = mixColumns(this.state);
      }
      this.state = addRoundKey(this.state, key);
    }
    return this.state;
  }
  public static void main(String[] args) {
    Rijndael r = new Rijndael();
    String input = "";
    String key = "";
    byte[] input1 =
      { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, (byte) 0x88,
          (byte) 0x99, (byte) 0xaa, (byte) 0xbb, (byte) 0xcc, (byte) 0xdd,
          (byte) 0xee, (byte) 0xff };
    byte[] key1 =
      { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
          0x0c, 0x0d, 0x0e, 0x0f };
    for (int i = 0; i <= 15; i++) {
      input += (char) input1[i];
      key += (char) key1[i];
    }
    String z = r.rijndael(input, key);
    System.out.println(z);
    for (int i = 0; i < z.length(); i++) {
      byte MN = (byte) z.charAt(i);
      System.out.print(Integer.toHexString(MN) + "****");
    }
  }
  public String getState() {
    return state;
  }
  private void setState(String state) {
    this.state = state;
  }
  public String getInput() {
    return input;
  }
  public void setInput(String input) {
    this.input = input;
  }
}