md5.java

短信系统SMS：支持普通短信、长短信和wap push短信的发送。

package com.ekun.sms.cmpp2;

/**
 * MD5加密类
 */
class MD5State
{

  /**
   * 128-byte state
   */
  int state[];

  /**
   * 64-bit character count (could be true Java long?)
   */
  int count[];

  /**
   * 64-byte buffer (512 bits) for storing to-be-hashed characters
   */
  byte buffer[];

  public MD5State()
  {
    buffer = new byte[64];
    count = new int[2];
    state = new int[4];

    state[0] = 0x67452301;
    state[1] = 0xefcdab89;
    state[2] = 0x98badcfe;
    state[3] = 0x10325476;

    count[0] = count[1] = 0;
  }

  /** Create this State as a copy of another state */
  public MD5State(MD5State from)
  {
    this();

    int i;

    for (i = 0; i < buffer.length; i++)
    {
      this.buffer[i] = from.buffer[i];
    }

    for (i = 0; i < state.length; i++)
    {
      this.state[i] = from.state[i];
    }

    for (i = 0; i < count.length; i++)
    {
      this.count[i] = from.count[i];
    }
  }
}

;

public class MD5
{

  /**
   * MD5 state
   */
  MD5State state;

  /**
   * If Final() has been called, finals is set to the current finals
   * state. Any Update() causes this to be set to null.
   */
  MD5State finals;

  /**
   * Padding for Final()
   */
  static byte padding[] =
      {
      (byte) 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  }
      ;

  /**
   * Initialize MD5 internal state (object can be reused just by
   * calling Init() after every Final()
   */
  public synchronized void Init()
  {
    state = new MD5State();
    finals = null;
  }

  /**
   * Class constructor
   */
  public MD5()
  {
    this.Init();
  }

  /**
   * Initialize class, and update hash with ob.toString()
   *
   * @param	ob	Object, ob.toString() is used to update hash
   *			after initialization
   */
  public MD5(Object ob)
  {
    this();
    Update(ob.toString());
  }

  private int rotate_left(int x, int n)
  {
    return (x << n) | (x >>> (32 - n));
  }

  /* I wonder how many loops and hoops you'll have to go through to
   get unsigned add for longs in java */

  private int uadd(int a, int b)
  {
    long aa, bb;

    aa = ( (long) a) & 0xffffffffL;
    bb = ( (long) b) & 0xffffffffL;

    aa += bb;

    return (int) (aa & 0xffffffffL);
  }

  private int uadd(int a, int b, int c)
  {
    return uadd(uadd(a, b), c);
  }

  private int uadd(int a, int b, int c, int d)
  {
    return uadd(uadd(a, b, c), d);
  }

  private int FF(int a, int b, int c, int d, int x, int s, int ac)
  {
    a = uadd(a, ( (b & c) | (~b & d)), x, ac);
    return uadd(rotate_left(a, s), b);
  }

  private int GG(int a, int b, int c, int d, int x, int s, int ac)
  {
    a = uadd(a, ( (b & d) | (c & ~d)), x, ac);
    return uadd(rotate_left(a, s), b);
  }

  private int HH(int a, int b, int c, int d, int x, int s, int ac)
  {
    a = uadd(a, (b ^ c ^ d), x, ac);
    return uadd(rotate_left(a, s), b);
  }

  private int II(int a, int b, int c, int d, int x, int s, int ac)
  {
    a = uadd(a, (c ^ (b | ~d)), x, ac);
    return uadd(rotate_left(a, s), b);
  }

  private int[] Decode(byte buffer[], int len, int shift)
  {
    int out[];
    int i, j;

    out = new int[16];

    for (i = j = 0; j < len; i++, j += 4)
    {
      out[i] = ( (int) (buffer[j + shift] & 0xff)) |
          ( ( (int) (buffer[j + 1 + shift] & 0xff)) << 8) |
          ( ( (int) (buffer[j + 2 + shift] & 0xff)) << 16) |
          ( ( (int) (buffer[j + 3 + shift] & 0xff)) << 24);

    }

    return out;
  }

  private void Transform(MD5State state, byte buffer[], int shift)
  {
    int
        a = state.state[0],
        b = state.state[1],
        c = state.state[2],
        d = state.state[3],
        x[];

    x = Decode(buffer, 64, shift);

    /* Round 1 */
    a = FF(a, b, c, d, x[0], 7, 0xd76aa478); /* 1 */
    d = FF(d, a, b, c, x[1], 12, 0xe8c7b756); /* 2 */
    c = FF(c, d, a, b, x[2], 17, 0x242070db); /* 3 */
    b = FF(b, c, d, a, x[3], 22, 0xc1bdceee); /* 4 */
    a = FF(a, b, c, d, x[4], 7, 0xf57c0faf); /* 5 */
    d = FF(d, a, b, c, x[5], 12, 0x4787c62a); /* 6 */
    c = FF(c, d, a, b, x[6], 17, 0xa8304613); /* 7 */
    b = FF(b, c, d, a, x[7], 22, 0xfd469501); /* 8 */
    a = FF(a, b, c, d, x[8], 7, 0x698098d8); /* 9 */
    d = FF(d, a, b, c, x[9], 12, 0x8b44f7af); /* 10 */
    c = FF(c, d, a, b, x[10], 17, 0xffff5bb1); /* 11 */
    b = FF(b, c, d, a, x[11], 22, 0x895cd7be); /* 12 */
    a = FF(a, b, c, d, x[12], 7, 0x6b901122); /* 13 */
    d = FF(d, a, b, c, x[13], 12, 0xfd987193); /* 14 */
    c = FF(c, d, a, b, x[14], 17, 0xa679438e); /* 15 */
    b = FF(b, c, d, a, x[15], 22, 0x49b40821); /* 16 */

    /* Round 2 */
    a = GG(a, b, c, d, x[1], 5, 0xf61e2562); /* 17 */
    d = GG(d, a, b, c, x[6], 9, 0xc040b340); /* 18 */
    c = GG(c, d, a, b, x[11], 14, 0x265e5a51); /* 19 */
    b = GG(b, c, d, a, x[0], 20, 0xe9b6c7aa); /* 20 */
    a = GG(a, b, c, d, x[5], 5, 0xd62f105d); /* 21 */
    d = GG(d, a, b, c, x[10], 9, 0x2441453); /* 22 */
    c = GG(c, d, a, b, x[15], 14, 0xd8a1e681); /* 23 */
    b = GG(b, c, d, a, x[4], 20, 0xe7d3fbc8); /* 24 */
    a = GG(a, b, c, d, x[9], 5, 0x21e1cde6); /* 25 */
    d = GG(d, a, b, c, x[14], 9, 0xc33707d6); /* 26 */
    c = GG(c, d, a, b, x[3], 14, 0xf4d50d87); /* 27 */
    b = GG(b, c, d, a, x[8], 20, 0x455a14ed); /* 28 */
    a = GG(a, b, c, d, x[13], 5, 0xa9e3e905); /* 29 */
    d = GG(d, a, b, c, x[2], 9, 0xfcefa3f8); /* 30 */
    c = GG(c, d, a, b, x[7], 14, 0x676f02d9); /* 31 */
    b = GG(b, c, d, a, x[12], 20, 0x8d2a4c8a); /* 32 */

    /* Round 3 */
    a = HH(a, b, c, d, x[5], 4, 0xfffa3942); /* 33 */
    d = HH(d, a, b, c, x[8], 11, 0x8771f681); /* 34 */
    c = HH(c, d, a, b, x[11], 16, 0x6d9d6122); /* 35 */
    b = HH(b, c, d, a, x[14], 23, 0xfde5380c); /* 36 */
    a = HH(a, b, c, d, x[1], 4, 0xa4beea44); /* 37 */
    d = HH(d, a, b, c, x[4], 11, 0x4bdecfa9); /* 38 */
    c = HH(c, d, a, b, x[7], 16, 0xf6bb4b60); /* 39 */
    b = HH(b, c, d, a, x[10], 23, 0xbebfbc70); /* 40 */
    a = HH(a, b, c, d, x[13], 4, 0x289b7ec6); /* 41 */
    d = HH(d, a, b, c, x[0], 11, 0xeaa127fa); /* 42 */
    c = HH(c, d, a, b, x[3], 16, 0xd4ef3085); /* 43 */
    b = HH(b, c, d, a, x[6], 23, 0x4881d05); /* 44 */
    a = HH(a, b, c, d, x[9], 4, 0xd9d4d039); /* 45 */
    d = HH(d, a, b, c, x[12], 11, 0xe6db99e5); /* 46 */
    c = HH(c, d, a, b, x[15], 16, 0x1fa27cf8); /* 47 */
    b = HH(b, c, d, a, x[2], 23, 0xc4ac5665); /* 48 */

    /* Round 4 */
    a = II(a, b, c, d, x[0], 6, 0xf4292244); /* 49 */
    d = II(d, a, b, c, x[7], 10, 0x432aff97); /* 50 */
    c = II(c, d, a, b, x[14], 15, 0xab9423a7); /* 51 */
    b = II(b, c, d, a, x[5], 21, 0xfc93a039); /* 52 */
    a = II(a, b, c, d, x[12], 6, 0x655b59c3); /* 53 */
    d = II(d, a, b, c, x[3], 10, 0x8f0ccc92); /* 54 */
    c = II(c, d, a, b, x[10], 15, 0xffeff47d); /* 55 */
    b = II(b, c, d, a, x[1], 21, 0x85845dd1); /* 56 */
    a = II(a, b, c, d, x[8], 6, 0x6fa87e4f); /* 57 */
    d = II(d, a, b, c, x[15], 10, 0xfe2ce6e0); /* 58 */
    c = II(c, d, a, b, x[6], 15, 0xa3014314); /* 59 */
    b = II(b, c, d, a, x[13], 21, 0x4e0811a1); /* 60 */
    a = II(a, b, c, d, x[4], 6, 0xf7537e82); /* 61 */
    d = II(d, a, b, c, x[11], 10, 0xbd3af235); /* 62 */
    c = II(c, d, a, b, x[2], 15, 0x2ad7d2bb); /* 63 */
    b = II(b, c, d, a, x[9], 21, 0xeb86d391); /* 64 */

    state.state[0] += a;
    state.state[1] += b;
    state.state[2] += c;
    state.state[3] += d;
  }

  /**
   * Updates hash with the bytebuffer given (using at maximum length bytes from
   * that buffer)
   *
   * @param state	Which state is updated
   * @param buffer	Array of bytes to be hashed
   * @param offset	Offset to buffer array
   * @param length	Use at maximum `length' bytes (absolute
   *			maximum is buffer.length)
   */
  public void Update(MD5State stat, byte buffer[], int offset, int length)
  {
    int index, partlen, i, start;

    finals = null;

    /* Length can be told to be shorter, but not inter */
    if ( (length - offset) > buffer.length)
    {
      length = buffer.length - offset;
    }

    /* compute number of bytes mod 64 */
    index = (int) (stat.count[0] >>> 3) & 0x3f;

    if ( (stat.count[0] += (length << 3)) <
        (length << 3))
    {
      stat.count[1]++;
    }

    stat.count[1] += length >>> 29;

    partlen = 64 - index;

    if (length >= partlen)
    {
      for (i = 0; i < partlen; i++)
      {
        stat.buffer[i + index] = buffer[i + offset];
      }

      Transform(stat, stat.buffer, 0);

      for (i = partlen; (i + 63) < length; i += 64)
      {
        Transform(stat, buffer, i);
      }

      index = 0;
    }
    else
    {
      i = 0;
    }

    /* buffer remaining input */
    if (i < length)
    {
      start = i;
      for (; i < length; i++)
      {
        stat.buffer[index + i - start] = buffer[i + offset];
      }
    }
  }

  /*
   * Update()s for other datatypes than byte[] also. Update(byte[], int)
   * is only the main driver.
   */

  /**
   * Plain update, updates this object
   */

  public void Update(byte buffer[], int offset, int length)
  {
    Update(this.state, buffer, offset, length);
  }

  public void Update(byte buffer[], int length)
  {
    Update(this.state, buffer, 0, length);
  }

  /**
   * Updates hash with given array of bytes
   *
   * @param buffer	Array of bytes to use for updating the hash
   */
  public void Update(byte buffer[])
  {
    Update(buffer, 0, buffer.length);
  }

  /**
   * Updates hash with a single byte
   *
   * @param b		Single byte to update the hash
   */
  public void Update(byte b)
  {
    byte buffer[] = new byte[1];

    buffer[0] = b;

    Update(buffer, 1);
  }

  /**
   * Update buffer with given string.
   *
   * @param s		String to be update to hash (is used as
   *		       	s.getBytes())
   */
  public void Update(String s)
  {
    byte chars[];

    chars = new byte[s.length()];
    s.getBytes(0, s.length(), chars, 0);

    Update(chars, chars.length);
  }

  /**
   * Update buffer with a single integer (only & 0xff part is used,
   * as a byte)
   *
   * @param i		Integer value, which is then converted to
   *			byte as i & 0xff
   */

  public void Update(int i)
  {
    Update( (byte) (i & 0xff));
  }

  private byte[] Encode(int input[], int len)
  {
    int i, j;
    byte out[];

    out = new byte[len];

    for (i = j = 0; j < len; i++, j += 4)
    {
      out[j] = (byte) (input[i] & 0xff);
      out[j + 1] = (byte) ( (input[i] >>> 8) & 0xff);
      out[j + 2] = (byte) ( (input[i] >>> 16) & 0xff);
      out[j + 3] = (byte) ( (input[i] >>> 24) & 0xff);
    }

    return out;
  }

  /**
   * Returns array of bytes (16 bytes) representing hash as of the
   * current state of this object. Note: getting a hash does not
   * invalidate the hash object, it only creates a copy of the real
   * state which is finalized.
   *
   * @return	Array of 16 bytes, the hash of all updated bytes
   */
  public synchronized byte[] Final()
  {
    byte bits[];
    int index, padlen;
    MD5State fin;

    if (finals == null)
    {
      fin = new MD5State(state);

      bits = Encode(fin.count, 8);

      index = (int) ( (fin.count[0] >>> 3) & 0x3f);
      padlen = (index < 56) ? (56 - index) : (120 - index);

      Update(fin, padding, 0, padlen);

      /**/
      Update(fin, bits, 0, 8);

      /* Update() sets finalds to null */
      finals = fin;
    }

    return Encode(finals.state, 16);
  }

  /**
   * Turns array of bytes into string representing each byte as
   * unsigned hex number.
   *
   * @param hash	Array of bytes to convert to hex-string
   * @return	Generated hex string
   */
  public static String asHex(byte hash[])
  {
    StringBuffer buf = new StringBuffer(hash.length * 2);
    int i;

    for (i = 0; i < hash.length; i++)
    {
      if ( ( (int) hash[i] & 0xff) < 0x10)
      {
        buf.append("0");
      }

      buf.append(Long.toString( (int) hash[i] & 0xff, 16));
    }

    return buf.toString();
  }

  /**
   * Returns 32-character hex representation of this objects hash
   *
   * @return String of this object's hash
   */
  public String asHex()
  {
    return asHex(this.Final());
  }
}