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java.lang.Object
   |
   +----edu.utah.janos.ants.utils.MD5

Summary

public final class  MD5
     extends java.lang.Object
{
          // Fields 5
     private final byte[] buffer;
     private final int[] count;
     private static final byte[] padding;
     private final int[] state;
     private final int[] tx;

          // Constructors 1
     public MD5();

          // Methods 14
     private static int FF(int, int, int, int, int, int, int);
     private static int GG(int, int, int, int, int, int, int);
     private static int HH(int, int, int, int, int, int, int);
     private static int II(int, int, int, int, int, int, int);
     public static byte[] hash(byte[]);
     public static byte[] hash(byte[], int, int);
     private static byte[] ints2bytes(int[]);
     private static int rotleft(int, int);
     public static String toString(byte[]);

     public byte[] hash();
     private void transform(byte[], int);
     public void update(byte[]);
     public void update(byte[], int, int);
     public void update(String);
}

Implementation of RSA's MD5 hash generator

This code is loosely based on the RSA reference implementation and an early Java port of it by Santeri Paavolainen.

Objects of this class are single use only -- clients must ensure that only one hash is computed, and sequentially too. Hashes are returned as an array of 16 bytes.

Usage:

   byte[] hash = MD5.hash(bytes);   // single pass mode
 

or

   MD5 digest = new MD5();          // multiple pass mode
   digest.update(bytes);
   digest.update(morebytes);
   byte[] hash = digest.hash();
 

(Pat) Optimizations: combine all of the arrays into a single array and use fixed offsets.

Author:

David Wetherall (djw@lcs.mit.edu)

Fields

· state

Summary  |  Top

   private final int[] state

128-bit state

   private final int[] tx

64-byte transform pass

   private final int[] count

64-bit character count

   private final byte[] buffer

64-byte overflow buffer

   private static final byte[] padding

Constructors

· MD5

Summary  |  Top

   public MD5() 

   private static int rotleft(int x, 
                              int n) 

   private static int FF(int a, 
                         int b, 
                         int c, 
                         int d, 
                         int x, 
                         int s, 
                         int ac) 

   private static int GG(int a, 
                         int b, 
                         int c, 
                         int d, 
                         int x, 
                         int s, 
                         int ac) 

   private static int HH(int a, 
                         int b, 
                         int c, 
                         int d, 
                         int x, 
                         int s, 
                         int ac) 

   private static int II(int a, 
                         int b, 
                         int c, 
                         int d, 
                         int x, 
                         int s, 
                         int ac) 

   private void transform(byte[] buf, 
                          int shift) 

   public void update(byte[] buf, 
                      int offset, 
                      int length) 

   public void update(byte[] buf) 

   public void update(String s) 

   private static byte[] ints2bytes(int[] input) 

   public byte[] hash() 

   public static byte[] hash(byte[] buf, 
                             int off, 
                             int len) 

   public static byte[] hash(byte[] buf) 

   public static String toString(byte[] hash) 

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