iaik.me.security.dsa
Class DSASignature

java.lang.Object
  |
  +--iaik.me.security.Signature
        |
        +--iaik.me.security.dsa.DSASignature

public class DSASignature

extends Signature

Fields inherited from class iaik.me.security.Signature

md, random

Constructor Summary

DSASignature()

Method Summary

void	initSign(PrivateKey privateKey, SecureRandom random) Initializes the signature instance for signing with a private key and a random number generator.
void	initVerify(PublicKey publicKey) Initializes the signature instance for verifiying a signature.
byte[]	sign() Creates a signature with the given data and private key.
void	update(byte[] input, int offset, int len) Updates the signature instance with the data that shall be signed or the data whose signature shall be verified.
boolean	verify(byte[] signature) This method verifies a given signature.

Methods inherited from class iaik.me.security.Signature

getAlgorithm, getInstance, register, update

Methods inherited from class java.lang.Object

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

Constructor Detail

DSASignature

public DSASignature()
             throws CryptoException

Method Detail

initSign

public void initSign(PrivateKey privateKey,
                     SecureRandom random)
              throws CryptoException

Description copied from class: Signature

Initializes the signature instance for signing with a private key and a random number generator.

Overrides:

initSign in class Signature

Following copied from class: iaik.me.security.Signature

Parameters:

privateKey - the signer's private key

random - optional if you want to use your own random number generator (if not, set this value to null).

Throws:

CryptoException -

initVerify

public void initVerify(PublicKey publicKey)
                throws CryptoException

Description copied from class: Signature

Initializes the signature instance for verifiying a signature.

Overrides:

initVerify in class Signature

Following copied from class: iaik.me.security.Signature

Parameters:

publicKey - the signer's public key

Throws:

CryptoException -

update

public void update(byte[] input,
                   int offset,
                   int len)
            throws CryptoException

Description copied from class: Signature

Updates the signature instance with the data that shall be signed or the data whose signature shall be verified. Use this method in case you don't want the whole byte array as input.

Overrides:

update in class Signature

Following copied from class: iaik.me.security.Signature

Parameters:

input - the input data

offset - starting index in the byte array

len - number of bytes to use as input beginnig from the starting index

Throws:

CryptoException -

verify

public boolean verify(byte[] signature)
               throws CryptoException

Description copied from class: Signature

This method verifies a given signature. After initializing the signature instance do this:

 byte[] signature = rsa.sign();
 

to get the signature value.

Overrides:

verify in class Signature

Following copied from class: iaik.me.security.Signature

Parameters:

signature - the signature to be verified

Returns:

true if the signature could be successfully verified.

Throws:

CryptoException -

sign

public byte[] sign()
            throws CryptoException

Description copied from class: Signature

Creates a signature with the given data and private key.

Overrides:

sign in class Signature

Following copied from class: iaik.me.security.Signature

Returns:

the signature as byte array

Throws:

CryptoException -