com.antiaction.digest
Class MD5

java.lang.Object
  |
  +--com.antiaction.digest.MD5

public class MD5

extends java.lang.Object

Java implementation of the MD5 digest algorithm described in rfc1321. Based on the reference implementation in C.

Version:

1.00

Author:

Nicholas Clarke

Field Summary

protected byte[]	buffer Buffer for mid block processing.
protected int	bufferedbytes Buffered bytes from previous call.
protected long	count Processed bit count.
protected static java.lang.String	hexList Hexadecimal conversion tabel.
protected static byte[]	PADDING Padding tabel used to block data.
protected static int	S11 Constant for MD5Transform routine.
protected static int	S12 Constant for MD5Transform routine.
protected static int	S13 Constant for MD5Transform routine.
protected static int	S14 Constant for MD5Transform routine.
protected static int	S21 Constant for MD5Transform routine.
protected static int	S22 Constant for MD5Transform routine.
protected static int	S23 Constant for MD5Transform routine.
protected static int	S24 Constant for MD5Transform routine.
protected static int	S31 Constant for MD5Transform routine.
protected static int	S32 Constant for MD5Transform routine.
protected static int	S33 Constant for MD5Transform routine.
protected static int	S34 Constant for MD5Transform routine.
protected static int	S41 Constant for MD5Transform routine.
protected static int	S42 Constant for MD5Transform routine.
protected static int	S43 Constant for MD5Transform routine.
protected static int	S44 Constant for MD5Transform routine.
protected int[]	state Transformation states.
protected int[]	x Temporary transformation data.

Constructor Summary

MD5()
Initialize object and state.

Method Summary

static void	Decode(int[] output, byte[] input, int offset, int len) Decodes input (unsigned char) into output (UINT4).
static void	Encode(byte[] output, int[] input, int len) Encodes input (UINT4) into output (unsigned char).
protected static int	F(int x, int y, int z) Basic MD5 function.
protected static int	FF(int a, int b, int c, int d, int x, int s, int ac) Transformations for rounds 1, 2, 3, and 4.
void	Final(byte[] digest) MD5 finalization.
protected static int	G(int x, int y, int z) Basic MD5 function.
protected static int	GG(int a, int b, int c, int d, int x, int s, int ac) Transformations for rounds 1, 2, 3, and 4.
protected static int	H(int x, int y, int z) Basic MD5 function.
protected static int	HH(int a, int b, int c, int d, int x, int s, int ac) Transformations for rounds 1, 2, 3, and 4.
protected static int	I(int x, int y, int z) Basic MD5 function.
protected static int	II(int a, int b, int c, int d, int x, int s, int ac) Transformations for rounds 1, 2, 3, and 4.
void	Init() Initialize state and all internal data structures.
static java.lang.String	MDFile(java.io.File infile) Returns the message digest of the file content.
static java.lang.String	MDFile(java.lang.String fname) Returns the message digest of the file content.
static java.lang.String	MDString(byte[] digest) Returns the string representation of a message digest.
static java.lang.String	MDString(java.lang.String s) Returns the message digest of the string argument.
protected static int	ROTATE_LEFT(int x, int n) ROTATE_LEFT rotates x left n bits.
protected void	Transform(byte[] block, int offset) MD5 basic transformation.
void	Update(byte[] input, int inputOffset, int inputLen) MD5 block update operation.

Methods inherited from class java.lang.Object

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

Field Detail

hexList

protected static final java.lang.String hexList

Hexadecimal conversion tabel.

S11

protected static final int S11

Constant for MD5Transform routine.

S12

protected static final int S12

Constant for MD5Transform routine.

S13

protected static final int S13

Constant for MD5Transform routine.

S14

protected static final int S14

Constant for MD5Transform routine.

S21

protected static final int S21

Constant for MD5Transform routine.

S22

protected static final int S22

Constant for MD5Transform routine.

S23

protected static final int S23

Constant for MD5Transform routine.

S24

protected static final int S24

Constant for MD5Transform routine.

S31

protected static final int S31

Constant for MD5Transform routine.

S32

protected static final int S32

Constant for MD5Transform routine.

S33

protected static final int S33

Constant for MD5Transform routine.

S34

protected static final int S34

Constant for MD5Transform routine.

S41

protected static final int S41

Constant for MD5Transform routine.

S42

protected static final int S42

Constant for MD5Transform routine.

S43

protected static final int S43

Constant for MD5Transform routine.

S44

protected static final int S44

Constant for MD5Transform routine.

PADDING

protected static final byte[] PADDING

Padding tabel used to block data.

state

protected int[] state

Transformation states.

count

protected long count

Processed bit count.

x

protected int[] x

Temporary transformation data.

buffer

protected byte[] buffer

Buffer for mid block processing.

bufferedbytes

protected int bufferedbytes

Buffered bytes from previous call.

Constructor Detail

MD5

public MD5()

Initialize object and state.

Method Detail

F

protected static int F(int x,
                       int y,
                       int z)

Basic MD5 function.

G

protected static int G(int x,
                       int y,
                       int z)

Basic MD5 function.

H

protected static int H(int x,
                       int y,
                       int z)

Basic MD5 function.

I

protected static int I(int x,
                       int y,
                       int z)

Basic MD5 function.

ROTATE_LEFT

protected static int ROTATE_LEFT(int x,
                                 int n)

ROTATE_LEFT rotates x left n bits.

Parameters:

x - integer to rotate.

n - positions to rotate.

Returns:

rotated integer.

FF

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

Transformations for rounds 1, 2, 3, and 4. Rotation is separate from addition to prevent recomputation.

GG

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

Transformations for rounds 1, 2, 3, and 4. Rotation is separate from addition to prevent recomputation.

HH

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

Transformations for rounds 1, 2, 3, and 4. Rotation is separate from addition to prevent recomputation.

II

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

Transformations for rounds 1, 2, 3, and 4. Rotation is separate from addition to prevent recomputation.

Decode

public static void Decode(int[] output,
                          byte[] input,
                          int offset,
                          int len)

Decodes input (unsigned char) into output (UINT4). Assumes len is a multiple of 4.

Parameters:

output - integer array where converted data is stored.

input - byte array with source data.

offset - offset in source data.

len - length of data to convert.

Returns:

decoded data.

Encode

public static void Encode(byte[] output,
                          int[] input,
                          int len)

Encodes input (UINT4) into output (unsigned char). Assumes len is a multiple of 4.

Parameters:

output - array of bytes where converted data is stored.

input - integer array with source data.

offset - offset in source data.

len - length of data to convert.

Returns:

encoded data.

Transform

protected void Transform(byte[] block,
                         int offset)

MD5 basic transformation. Transforms state based on block.

Parameters:

block - data to transform.

offset - offset in data.

Init

public void Init()

Initialize state and all internal data structures.

See Also:

Update(byte[], int, int), Final(byte[])

Update

public void Update(byte[] input,
                   int inputOffset,
                   int inputLen)

MD5 block update operation. Continues an MD5 message-digest operation, processing another message block, and updating the context.

Parameters:

input - byte array of in data.

inputOffset - starting offset.

inputLen - length of data to digest.

See Also:

Init(), Final(byte[])

Final

public void Final(byte[] digest)

MD5 finalization. Ends an MD5 message-digest operation, writing the the message digest and zeroizing the context.

Parameters:

digest - array where the digest is to be placed.

See Also:

Init(), Update(byte[], int, int)

MDString

public static java.lang.String MDString(byte[] digest)

Returns the string representation of a message digest.

Parameters:

digest - byte array containing a message digest.

Returns:

the string representation of a message digest.

MDString

public static java.lang.String MDString(java.lang.String s)

Returns the message digest of the string argument.

Parameters:

s - string to digest.

Returns:

the message digest of the string argument.

MDFile

public static java.lang.String MDFile(java.lang.String fname)

Returns the message digest of the file content.

Parameters:

fname - filename.

Returns:

the message digest of the file content.

MDFile

public static java.lang.String MDFile(java.io.File infile)

Returns the message digest of the file content.

Parameters:

infile - File handle.

Returns:

the message digest of the file content.