des.java

DES算法的JAVA实现源代码

   * @param input_start    Offset into input to start encryption.
   * @param length         Number of bytes to encrypt.
   * @param output         Output byte [] array.
   * @param output_start   Offset into output to place result.
   * @param ivec           Initialization vector. A byte [] array of length 8. Updated on exit.
   * @param num            Reference to an int used to keep track of 'how far' we are though ivec. Updated on exit.
   */

  void ofb64_encrypt(byte [] input, int input_start, int length, 
		     byte [] output, int output_start,
		     byte [] ivec,
		     int [] num);
}

/**
 * Des class. Does all modes of Des encryption.
 * Written by Jeremy Allison ([e-mail]) based on
 * C code from Eric Young ([e-mail]).
 */

class Des implements DesCrypt {

  /**
   * Constant. Pass this to functions that have a boolean
   * encrypt parameter to tell them to encrypt the data.
   */
  public static final boolean ENCRYPT = true;

  /**
   * Constant. Pass this to functions that have a boolean
   * encrypt parameter to tell them to decrypt the data.
   */
  public static final boolean DECRYPT = false;

  private DesKey ks_;

  private static final int des_SPtrans_[][] = {
    {
      /* nibble 0 */
      0x00820200, 0x00020000, 0x80800000, 0x80820200,
      0x00800000, 0x80020200, 0x80020000, 0x80800000,
      0x80020200, 0x00820200, 0x00820000, 0x80000200,
      0x80800200, 0x00800000, 0x00000000, 0x80020000,
      0x00020000, 0x80000000, 0x00800200, 0x00020200,
      0x80820200, 0x00820000, 0x80000200, 0x00800200,
      0x80000000, 0x00000200, 0x00020200, 0x80820000,
      0x00000200, 0x80800200, 0x80820000, 0x00000000,
      0x00000000, 0x80820200, 0x00800200, 0x80020000,
      0x00820200, 0x00020000, 0x80000200, 0x00800200,
      0x80820000, 0x00000200, 0x00020200, 0x80800000,
      0x80020200, 0x80000000, 0x80800000, 0x00820000,
      0x80820200, 0x00020200, 0x00820000, 0x80800200,
      0x00800000, 0x80000200, 0x80020000, 0x00000000,
      0x00020000, 0x00800000, 0x80800200, 0x00820200,
      0x80000000, 0x80820000, 0x00000200, 0x80020200
    },{
      /* nibble 1 */
      0x10042004, 0x00000000, 0x00042000, 0x10040000,
      0x10000004, 0x00002004, 0x10002000, 0x00042000,
      0x00002000, 0x10040004, 0x00000004, 0x10002000,
      0x00040004, 0x10042000, 0x10040000, 0x00000004,
      0x00040000, 0x10002004, 0x10040004, 0x00002000,
      0x00042004, 0x10000000, 0x00000000, 0x00040004,
      0x10002004, 0x00042004, 0x10042000, 0x10000004,
      0x10000000, 0x00040000, 0x00002004, 0x10042004,
      0x00040004, 0x10042000, 0x10002000, 0x00042004,
      0x10042004, 0x00040004, 0x10000004, 0x00000000,
      0x10000000, 0x00002004, 0x00040000, 0x10040004,
      0x00002000, 0x10000000, 0x00042004, 0x10002004,
      0x10042000, 0x00002000, 0x00000000, 0x10000004,
      0x00000004, 0x10042004, 0x00042000, 0x10040000,
      0x10040004, 0x00040000, 0x00002004, 0x10002000,
      0x10002004, 0x00000004, 0x10040000, 0x00042000
    },{
      /* nibble 2 */
      0x41000000, 0x01010040, 0x00000040, 0x41000040,
      0x40010000, 0x01000000, 0x41000040, 0x00010040,
      0x01000040, 0x00010000, 0x01010000, 0x40000000,
      0x41010040, 0x40000040, 0x40000000, 0x41010000,
      0x00000000, 0x40010000, 0x01010040, 0x00000040,
      0x40000040, 0x41010040, 0x00010000, 0x41000000,
      0x41010000, 0x01000040, 0x40010040, 0x01010000,
      0x00010040, 0x00000000, 0x01000000, 0x40010040,
      0x01010040, 0x00000040, 0x40000000, 0x00010000,
      0x40000040, 0x40010000, 0x01010000, 0x41000040,
      0x00000000, 0x01010040, 0x00010040, 0x41010000,
      0x40010000, 0x01000000, 0x41010040, 0x40000000,
      0x40010040, 0x41000000, 0x01000000, 0x41010040,
      0x00010000, 0x01000040, 0x41000040, 0x00010040,
      0x01000040, 0x00000000, 0x41010000, 0x40000040,
      0x41000000, 0x40010040, 0x00000040, 0x01010000
    },{
      /* nibble 3 */
      0x00100402, 0x04000400, 0x00000002, 0x04100402,
      0x00000000, 0x04100000, 0x04000402, 0x00100002,
      0x04100400, 0x04000002, 0x04000000, 0x00000402,
      0x04000002, 0x00100402, 0x00100000, 0x04000000,
      0x04100002, 0x00100400, 0x00000400, 0x00000002,
      0x00100400, 0x04000402, 0x04100000, 0x00000400,
      0x00000402, 0x00000000, 0x00100002, 0x04100400,
      0x04000400, 0x04100002, 0x04100402, 0x00100000,
      0x04100002, 0x00000402, 0x00100000, 0x04000002,
      0x00100400, 0x04000400, 0x00000002, 0x04100000,
      0x04000402, 0x00000000, 0x00000400, 0x00100002,
      0x00000000, 0x04100002, 0x04100400, 0x00000400,
      0x04000000, 0x04100402, 0x00100402, 0x00100000,
      0x04100402, 0x00000002, 0x04000400, 0x00100402,
      0x00100002, 0x00100400, 0x04100000, 0x04000402,
      0x00000402, 0x04000000, 0x04000002, 0x04100400
    },{
      /* nibble 4 */
      0x02000000, 0x00004000, 0x00000100, 0x02004108,
      0x02004008, 0x02000100, 0x00004108, 0x02004000,
      0x00004000, 0x00000008, 0x02000008, 0x00004100,
      0x02000108, 0x02004008, 0x02004100, 0x00000000,
      0x00004100, 0x02000000, 0x00004008, 0x00000108,
      0x02000100, 0x00004108, 0x00000000, 0x02000008,
      0x00000008, 0x02000108, 0x02004108, 0x00004008,
      0x02004000, 0x00000100, 0x00000108, 0x02004100,
      0x02004100, 0x02000108, 0x00004008, 0x02004000,
      0x00004000, 0x00000008, 0x02000008, 0x02000100,
      0x02000000, 0x00004100, 0x02004108, 0x00000000,
      0x00004108, 0x02000000, 0x00000100, 0x00004008,
      0x02000108, 0x00000100, 0x00000000, 0x02004108,
      0x02004008, 0x02004100, 0x00000108, 0x00004000,
      0x00004100, 0x02004008, 0x02000100, 0x00000108,
      0x00000008, 0x00004108, 0x02004000, 0x02000008
    },{
      /* nibble 5 */
      0x20000010, 0x00080010, 0x00000000, 0x20080800,
      0x00080010, 0x00000800, 0x20000810, 0x00080000,
      0x00000810, 0x20080810, 0x00080800, 0x20000000,
      0x20000800, 0x20000010, 0x20080000, 0x00080810,
      0x00080000, 0x20000810, 0x20080010, 0x00000000,
      0x00000800, 0x00000010, 0x20080800, 0x20080010,
      0x20080810, 0x20080000, 0x20000000, 0x00000810,
      0x00000010, 0x00080800, 0x00080810, 0x20000800,
      0x00000810, 0x20000000, 0x20000800, 0x00080810,
      0x20080800, 0x00080010, 0x00000000, 0x20000800,
      0x20000000, 0x00000800, 0x20080010, 0x00080000,
      0x00080010, 0x20080810, 0x00080800, 0x00000010,
      0x20080810, 0x00080800, 0x00080000, 0x20000810,
      0x20000010, 0x20080000, 0x00080810, 0x00000000,
      0x00000800, 0x20000010, 0x20000810, 0x20080800,
      0x20080000, 0x00000810, 0x00000010, 0x20080010
    },{
      /* nibble 6 */
      0x00001000, 0x00000080, 0x00400080, 0x00400001,
      0x00401081, 0x00001001, 0x00001080, 0x00000000,
      0x00400000, 0x00400081, 0x00000081, 0x00401000,
      0x00000001, 0x00401080, 0x00401000, 0x00000081,
      0x00400081, 0x00001000, 0x00001001, 0x00401081,
      0x00000000, 0x00400080, 0x00400001, 0x00001080,
      0x00401001, 0x00001081, 0x00401080, 0x00000001,
      0x00001081, 0x00401001, 0x00000080, 0x00400000,
      0x00001081, 0x00401000, 0x00401001, 0x00000081,
      0x00001000, 0x00000080, 0x00400000, 0x00401001,
      0x00400081, 0x00001081, 0x00001080, 0x00000000,
      0x00000080, 0x00400001, 0x00000001, 0x00400080,
      0x00000000, 0x00400081, 0x00400080, 0x00001080,
      0x00000081, 0x00001000, 0x00401081, 0x00400000,
      0x00401080, 0x00000001, 0x00001001, 0x00401081,
      0x00400001, 0x00401080, 0x00401000, 0x00001001
    },{
      /* nibble 7 */
      0x08200020, 0x08208000, 0x00008020, 0x00000000,
      0x08008000, 0x00200020, 0x08200000, 0x08208020,
      0x00000020, 0x08000000, 0x00208000, 0x00008020,
      0x00208020, 0x08008020, 0x08000020, 0x08200000,
      0x00008000, 0x00208020, 0x00200020, 0x08008000,
      0x08208020, 0x08000020, 0x00000000, 0x00208000,
      0x08000000, 0x00200000, 0x08008020, 0x08200020,
      0x00200000, 0x00008000, 0x08208000, 0x00000020,
      0x00200000, 0x00008000, 0x08000020, 0x08208020,
      0x00008020, 0x08000000, 0x00000000, 0x00208000,
      0x08200020, 0x08008020, 0x08008000, 0x00200020,
      0x08208000, 0x00000020, 0x00200020, 0x08008000,
      0x08208020, 0x00200000, 0x08200000, 0x08000020,
      0x00208000, 0x00008020, 0x08008020, 0x08200000,
      0x00000020, 0x08208000, 0x00208020, 0x00000000,
      0x08000000, 0x08200020, 0x00008000, 0x00208020
    }
  };

  /**
   * Internal routine only exported for use by TripleDes code.
   */
  /*
   * Initial permutation.
   *
   #define IP(l,r) \
   { \
   register DES_LONG tt; \
   PERM_OP(r,l,tt, 4,0x0f0f0f0fL); \
   PERM_OP(l,r,tt,16,0x0000ffffL); \
   PERM_OP(r,l,tt, 2,0x33333333L); \
   PERM_OP(l,r,tt, 8,0x00ff00ffL); \
   PERM_OP(r,l,tt, 1,0x55555555L); \
   }
   */

  public void IP(int [] ref_to_l, int [] ref_to_r) {
    int tt = 0;
    Int32Manipulator.PERM_OP(ref_to_r, ref_to_l, tt, 4, 0x0f0f0f0f);
    Int32Manipulator.PERM_OP(ref_to_l, ref_to_r, tt, 16, 0x0000ffff);
    Int32Manipulator.PERM_OP(ref_to_r, ref_to_l, tt, 2, 0x33333333);
    Int32Manipulator.PERM_OP(ref_to_l, ref_to_r, tt, 8, 0x00ff00ff);
    Int32Manipulator.PERM_OP(ref_to_r, ref_to_l, tt, 1, 0x55555555);
  }

  /**
   * Internal routine only exported for use by TripleDes code.
   */
  /*
   * Final permutation.
   *
   #define FP(l,r) \
   { \
   register DES_LONG tt; \
   PERM_OP(l,r,tt, 1,0x55555555L); \
   PERM_OP(r,l,tt, 8,0x00ff00ffL); \
   PERM_OP(l,r,tt, 2,0x33333333L); \
   PERM_OP(r,l,tt,16,0x0000ffffL); \
   PERM_OP(l,r,tt, 4,0x0f0f0f0fL); \
   }
   */

  public void FP(int [] ref_to_l, int [] ref_to_r) {
    int tt = 0;
    Int32Manipulator.PERM_OP(ref_to_l, ref_to_r, tt, 1, 0x55555555);
    Int32Manipulator.PERM_OP(ref_to_r, ref_to_l, tt, 8, 0x00ff00ff);
    Int32Manipulator.PERM_OP(ref_to_l, ref_to_r, tt, 2, 0x33333333);
    Int32Manipulator.PERM_OP(ref_to_r, ref_to_l, tt,16, 0x0000ffff);
    Int32Manipulator.PERM_OP(ref_to_l, ref_to_r, tt, 4, 0x0f0f0f0f);
  }

  /*
    #define D_ENCRYPT(Q,R,S) {\
    u=(R^s[S  ]); \
    t=R^s[S+1]; \
    t=((t>>4L)+(t<<28L)); \
    Q^=     des_SPtrans[1][(t     )&0x3f]| \
    des_SPtrans[3][(t>> 8L)&0x3f]| \
    des_SPtrans[5][(t>>16L)&0x3f]| \
    des_SPtrans[7][(t>>24L)&0x3f]| \
    des_SPtrans[0][(u     )&0x3f]| \
    des_SPtrans[2][(u>> 8L)&0x3f]| \
    des_SPtrans[4][(u>>16L)&0x3f]| \
    des_SPtrans[6][(u>>24L)&0x3f]; }
    */

  private void D_ENCRYPT(int [] ref_to_Q, int R, int S, int [] ref_to_u) {
    byte [] s = ks_.get_keysced();
    S = S*4; /* Remember, S is a int offset, int C */
    int s_at_S_offset = Int32Manipulator.bytes_to_int(s, S);
    int s_at_S_plus_one_offset = Int32Manipulator.bytes_to_int(s, S+4);

    ref_to_u[0] = R^s_at_S_offset;
    int tmp = R^s_at_S_plus_one_offset;
    tmp = (tmp>>>4) + (tmp<<28);
    ref_to_Q[0] ^= des_SPtrans_[1][(tmp             )&0x3f]|
      des_SPtrans_[3][(tmp>>>8         )&0x3f]|
      des_SPtrans_[5][(tmp>>>16        )&0x3f]|
      des_SPtrans_[7][(tmp>>>24        )&0x3f]|
      des_SPtrans_[0][(ref_to_u[0]     )&0x3f]|
      des_SPtrans_[2][(ref_to_u[0]>>> 8)&0x3f]|
      des_SPtrans_[4][(ref_to_u[0]>>>16)&0x3f]|
      des_SPtrans_[6][(ref_to_u[0]>>>24)&0x3f];
  }

  /**
   * Constructor for a Des Object. Takes an already
   * existing DesKey which will be used for all future
   * encryption/decryption with this Des object.
   * The passed in key is not checked for parity of weakness.
   *
   * @param key         Existing DesKey.
   */
  public Des(DesKey key) {
    ks_ = key;
  }

  /*
   * This is the internal encrypt routine, called by all the
   * other des encrypt/decrypt functions. It is not callable
   * outside the Des class.
   */

  private void des_encrypt(int [] data, boolean encrypt) {
    int tmp = 0;
    int [] ref_to_u = new int [1];
    int [] ref_to_r = new int [1];
    int [] ref_to_l = new int [1];

    ref_to_u[0] = data[0];
    ref_to_r[0] = data[1];

    IP(ref_to_u, ref_to_r);

    ref_to_l[0]=(ref_to_r[0]<<1)|(ref_to_r[0]>>>31);
    ref_to_r[0]=(ref_to_u[0]<<1)|(ref_to_u[0]>>>31);

    if (encrypt == Des.ENCRYPT) {
      for (int i = 0; i < 32; i+=4) {
	D_ENCRYPT(ref_to_l,ref_to_r[0],i+0, ref_to_u); /*  1 */
	D_ENCRYPT(ref_to_r,ref_to_l[0],i+2, ref_to_u); /*  2 */
      }
    } else {
      /* Decrypt */
      for (int i = 30; i > 0; i-=4) {
	D_ENCRYPT(ref_to_l,ref_to_r[0],i-0, ref_to_u); /* 16 */
	D_ENCRYPT(ref_to_r,ref_to_l[0],i-2, ref_to_u); /* 15 */
      }
    }

    ref_to_l[0] = (ref_to_l[0]>>>1)|(ref_to_l[0]<<31);
    ref_to_r[0] = (ref_to_r[0]>>>1)|(ref_to_r[0]<<31);

    FP(ref_to_r, ref_to_l);

    data[0]=ref_to_l[0];
    data[1]=ref_to_r[0];
  }

  /**
   * This is the a publicly callable variant of the
   * internal encrypt routine, called by all the
   * TripleDes encrypt/decrypt functions. The only difference
   * between this and the des_encrypt function is that this
   * doesn't do the initial and final permutations. This
   * optimises the speed of TripleDes as
   * IP() des_encrypt2() des_encrypt2() des_encrypt2() FP() 
   * is the same as
   * des_encrypt() des_encrypt() des_encrypt() 
   * except faster :-).
   * 
   * No parameters listed as this is only used by the TripleDes
   * class.
   */

  public void des_encrypt2(int [] data, boolean encrypt) {
    int tmp = 0;
    int [] ref_to_u = new int [1];
    int [] ref_to_r = new int [1];
    int [] ref_to_l = new int [1];

    ref_to_u[0] = data[0];
    ref_to_r[0] = data[1];

    ref_to_l[0]=(ref_to_r[0]<<1)|(ref_to_r[0]>>>31);
    ref_to_r[0]=(ref_to_u[0]<<1)|(ref_to_u[0]>>>31);

    if (encrypt == Des.ENCRYPT) {
      for (int i = 0; i < 32; i+=4) {
	D_ENCRYPT(ref_to_l,ref_to_r[0],i+0, ref_to_u); /*  1 */
	D_ENCRYPT(ref_to_r,ref_to_l[0],i+2, ref_to_u); /*  2 */
      }
    } else {
      /* Decrypt */
      for (int i = 30; i > 0; i-=4) {
	D_ENCRYPT(ref_to_l,ref_to_r[0],i-0, ref_to_u); /* 16 */
	D_ENCRYPT(ref_to_r,ref_to_l[0],i-2, ref_to_u); /* 15 */
      }
    }

    ref_to_l[0] = (ref_to_l[0]>>>1)|(ref_to_l[0]<<31);
    ref_to_r[0] = (ref_to_r[0]>>>1)|(ref_to_r[0]<<31);

    data[0]=ref_to_l[0];
    data[1]=ref_to_r[0];
  }

  /**
   * Do the ecb (Encrypt/Decrypt 8 bytes electronic code book)
   * mode. Encrypts 8 bytes starting at offset input_start in