org.mozilla.jss.crypto

Class JSSMessageDigest

java.lang.Object

org.mozilla.jss.crypto.JSSMessageDigest

Direct Known Subclasses:

PK11MessageDigest

public abstract class JSSMessageDigest
extends java.lang.Object

A class for performing message digesting (hashing) and MAC operations.

Constructor Summary

Constructors

Constructor and Description
JSSMessageDigest()

Method Summary

Methods

Modifier and Type	Method and Description
byte[]	digest() Completes digestion.
byte[]	digest(byte[] input) Provides final data to the digest, then completes it and returns the output.
abstract int	digest(byte[] buf, int offset, int len) Completes digesting, storing the result into the provided array.
abstract DigestAlgorithm	getAlgorithm() Returns the algorithm that this digest uses.
int	getOutputSize() Returns the length of the digest created by this digest's digest algorithm.
abstract void	initHMAC(SymmetricKey key) Initializes an HMAC digest with the given symmetric key.
abstract void	reset() Resets this digest for further use.
void	update(byte input) Updates the digest with a single byte of input.
void	update(byte[] input) Updates the digest with an array.
abstract void	update(byte[] input, int offset, int len) Updates the digest with a portion of an array.

Methods inherited from class java.lang.Object

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

Constructor Detail

JSSMessageDigest

public JSSMessageDigest()

Method Detail

initHMAC

public abstract void initHMAC(SymmetricKey key)
                       throws java.security.DigestException,
                              java.security.InvalidKeyException

Initializes an HMAC digest with the given symmetric key. This also has the effect of resetting the digest.

Throws:

java.security.DigestException - If this algorithm is not an HMAC algorithm.

java.security.InvalidKeyException - If the given key is not valid.

update

public void update(byte input)
            throws java.security.DigestException

Updates the digest with a single byte of input.

Throws:

java.security.DigestException

update

public abstract void update(byte[] input,
          int offset,
          int len)
                     throws java.security.DigestException

Updates the digest with a portion of an array.

Parameters:

input - An array from which to update the digest.

offset - The index in the array at which to start digesting.

len - The number of bytes to digest.

Throws:

java.security.DigestException - If an error occurs while digesting.

update

public void update(byte[] input)
            throws java.security.DigestException

Updates the digest with an array.

Parameters:

input - An array to feed to the digest.

Throws:

java.security.DigestException - If an error occurs while digesting.

digest

public byte[] digest()
              throws java.security.DigestException

Completes digestion.

Returns:

The, ahem, output of the digest operation.

Throws:

java.security.DigestException - If an error occurs while digesting.

digest

public abstract int digest(byte[] buf,
         int offset,
         int len)
                    throws java.security.DigestException

Completes digesting, storing the result into the provided array.

Parameters:

buf - The buffer in which to place the digest output.

offset - The offset in the buffer at which to store the output.

len - The amount of space available in the buffer for the digest output.

Returns:

The number of bytes actually stored into buf.

Throws:

java.security.DigestException - If the provided space is too small for the digest, or an error occurs with the digest.

digest

public byte[] digest(byte[] input)
              throws java.security.DigestException

Provides final data to the digest, then completes it and returns the output.

Parameters:

input - The digest's last meal.

Returns:

The completed digest.

Throws:

java.security.DigestException - If an error occurs while digesting.

reset

public abstract void reset()
                    throws java.security.DigestException

Resets this digest for further use. This clears all input and output streams. If this is an HMAC digest, the HMAC key is not cleared.

Throws:

java.security.DigestException

getAlgorithm

public abstract DigestAlgorithm getAlgorithm()

Returns the algorithm that this digest uses.

getOutputSize

public int getOutputSize()

Returns the length of the digest created by this digest's digest algorithm.

Returns:

The size in bytes of the output of this digest.