Package com.hierynomus.security.jce.messagedigest

Class MD4

  • public class MD4
extends java.security.MessageDigest
    MD4.java - An implementation of Ron Rivest's MD4 message digest algorithm. The MD4 algorithm is designed to be quite fast on 32-bit machines. In addition, the MD4 algorithm does not require any large substitution tables.
    Since:
    MINA 2.0.0-M3
    See Also:
    MD4 Message- Digest Algorithm by R. Rivest.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private int a
      The four registers initialized with the above IVs.
      private static int A
      The initial values of the four registers.
      private int b  
      private static int B  
      private byte[] buffer
      The internal buffer is BLOCK_LENGTH wide.
      static int BYTE_BLOCK_LENGTH
      The MD4 algorithm block length is 64 bytes wide.
      static int BYTE_DIGEST_LENGTH
      The MD4 algorithm message digest length is 16 bytes wide.
      private int c  
      private static int C  
      private int d  
      private static int D  
      private long msgLength
      Counts the total length of the data being digested.

    • Constructor Summary

      Constructors 
      Constructor Description
      MD4()
      Default constructor.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected byte[] engineDigest()
      protected int engineDigest​(byte[] buf, int offset, int len)
      protected int engineGetDigestLength()
      Returns the digest length in bytes.
      protected void engineReset()
      protected void engineUpdate​(byte b)
      protected void engineUpdate​(byte[] b, int offset, int len)
      private byte[] pad()
      Pads the buffer by appending the byte 0x80, then append as many zero bytes as necessary to make the buffer length a multiple of 64 bytes.
      private void process​(byte[] in, int offset)
      Process one 64-byte block.

      • Methods inherited from class java.security.MessageDigest

        clone, digest, digest, digest, getAlgorithm, getDigestLength, getInstance, getInstance, getInstance, getProvider, isEqual, reset, toString, update, update, update, update

      • Methods inherited from class java.security.MessageDigestSpi

        engineUpdate

      • Methods inherited from class java.lang.Object

        equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Field Detail

      • BYTE_DIGEST_LENGTH

        public static final int BYTE_DIGEST_LENGTH
        The MD4 algorithm message digest length is 16 bytes wide.
        See Also:
        Constant Field Values

      • BYTE_BLOCK_LENGTH

        public static final int BYTE_BLOCK_LENGTH
        The MD4 algorithm block length is 64 bytes wide.
        See Also:
        Constant Field Values

      • A

        private static final int A
        The initial values of the four registers. RFC gives the values in LE so we converted it as JAVA uses BE endianness.
        See Also:
        Constant Field Values

      • a

        private int a
        The four registers initialized with the above IVs.

      • b

        private int b

      • c

        private int c

      • d

        private int d

      • msgLength

        private long msgLength
        Counts the total length of the data being digested.

      • buffer

        private final byte[] buffer
        The internal buffer is BLOCK_LENGTH wide.

    • Constructor Detail

      • MD4

        public MD4()
        Default constructor.

    • Method Detail

      • engineGetDigestLength

        protected int engineGetDigestLength()
        Returns the digest length in bytes.
        Overrides:
        engineGetDigestLength in class java.security.MessageDigestSpi
        Returns:
        the digest length in bytes.

      • engineUpdate

        protected void engineUpdate​(byte b)
        Specified by:
        engineUpdate in class java.security.MessageDigestSpi

      • engineUpdate

        protected void engineUpdate​(byte[] b,
                            int offset,
                            int len)
        Specified by:
        engineUpdate in class java.security.MessageDigestSpi

      • engineDigest

        protected byte[] engineDigest()
        Specified by:
        engineDigest in class java.security.MessageDigestSpi

      • engineDigest

        protected int engineDigest​(byte[] buf,
                           int offset,
                           int len)
                    throws java.security.DigestException
        Overrides:
        engineDigest in class java.security.MessageDigestSpi
        Throws:
        java.security.DigestException

      • engineReset

        protected void engineReset()
        Specified by:
        engineReset in class java.security.MessageDigestSpi

      • pad

        private byte[] pad()
        Pads the buffer by appending the byte 0x80, then append as many zero bytes as necessary to make the buffer length a multiple of 64 bytes. The last 8 bytes will be filled with the length of the buffer in bits. If there's no room to store the length in bits in the block i.e the block is larger than 56 bytes then an additionnal 64-bytes block is appended.
        Returns:
        the pad byte array
        See Also:
        3.1 3.2 of the RFC 1320.

      • process

        private void process​(byte[] in,
                     int offset)
        Process one 64-byte block. Algorithm is constituted by three rounds. Note that F, G and H functions were inlined for improved performance.
        Parameters:
        in - the byte array to process
        offset - the offset at which the 64-byte block is stored