MerkleDamgard

Extending MerkleDamgard to create a custom hash function requires the implementation of a number of abstract methods. These include:

public uint digestSize();
protected void reset();
protected void createDigest(ubyte[] buf);
protected uint blockSize();
protected uint addSize();
protected void padMessage(ubyte[] data);
protected void transform(ubyte[] data);

In addition there exist two further abstract methods; these methods have empty default implementations since in some cases they are not required$(CLN)

protected abstract void padLength(ubyte[] data, ulong length);
protected abstract void extend();

The method padLength() is required to implement the SHA series of Hash functions and also the Tiger algorithm. Method extend() is required only to implement the MD2 digest.

The basic sequence of internal events is as follows:

transform(), 0 or more times
padMessage()
padLength()
transform()
extend()
createDigest()
reset()

package

class MerkleDamgard : Digest {

void createDigest(ubyte[] buf);

uint blockSize();

uint addSize [@property getter];

void padMessage(ubyte[] data);

void padLength(ubyte[] data, ulong length);

void transform(const(ubyte[]) data);

void extend();

this();

void reset();

MerkleDamgard update(const(void[]) input);

ubyte[] binaryDigest(ubyte[] buf);

static void littleEndian32(const(ubyte[]) input, uint[] output);

static void bigEndian32(const(ubyte[]) input, uint[] output);

static void littleEndian64(const(ubyte[]) input, ulong[] output);

static void bigEndian64(const(ubyte[]) input, ulong[] output);

static uint rotateLeft(uint x, uint n);

}

Constructors

this this(): Construct a digest

Members

Functions

binaryDigest ubyte[] binaryDigest(ubyte[] buf): Complete the digest
blockSize uint blockSize(): Digest block size
createDigest void createDigest(ubyte[] buf): Constructs the digest
extend void extend(): Final processing of digest.
padLength void padLength(ubyte[] data, ulong length): Performs the length padding
padMessage void padMessage(ubyte[] data): Pads the digest data
reset void reset(): Initialize the digest
transform void transform(const(ubyte[]) data): Performs the digest on a block of data
update MerkleDamgard update(const(void[]) input): Digest additional data

Properties

addSize uint addSize [@property getter]: Length padding size

Static functions

bigEndian32 void bigEndian32(const(ubyte[]) input, uint[] output): Converts 8 bit to 32 bit Big Endian
bigEndian64 void bigEndian64(const(ubyte[]) input, ulong[] output): Converts 8 bit to 64 bit Big Endian
littleEndian32 void littleEndian32(const(ubyte[]) input, uint[] output): Converts 8 bit to 32 bit Little Endian
littleEndian64 void littleEndian64(const(ubyte[]) input, ulong[] output): Converts 8 bit to 64 bit Little Endian
rotateLeft uint rotateLeft(uint x, uint n): Rotate left by n