org.dihedron.crypto.operations.sign

Class Signer

java.lang.Object

org.dihedron.crypto.CryptoService

org.dihedron.crypto.operations.sign.Signer

Direct Known Subclasses:

PdfSigner, PKCS7Signer

public abstract class Signer
extends CryptoService

This class acts as the base class, providing common functionalities, to all fashions of signers.

Field Summary

Fields

Modifier and Type	Field and Description
protected KeyRing	keyring The key ring (as a wrapper and helper to access the key store).
protected Provider	provider The security provider.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Signer(String alias, KeyRing keyring, Provider provider) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected String	getAlias() Returns the alias of the certificate to be used for signing.
protected KeyRing	getKeyRing() Returns the key ring containing the signature key.
protected Provider	getProvider() Returns the security provider backing up the key store.
abstract void	initialise() Initialises the object.
boolean	isEncapsulateData() Returns whether the data is going to be encapsulated along with the signature.
abstract byte[]	sign(byte[] data) Signs the given set of data.
abstract boolean	verify(byte[] signed) Verifies the signature of the given set of encapsulated data.
abstract boolean	verify(byte[] signed, byte[] data) Verifies the signature of the given set of detached data.

Methods inherited from class java.lang.Object

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

Field Detail

keyring

protected KeyRing keyring

The key ring (as a wrapper and helper to access the key store).

provider

protected Provider provider

The security provider.

Constructor Detail

Signer

protected Signer(String alias,
      KeyRing keyring,
      Provider provider)
          throws CryptoException

Constructor.

Parameters:

alias - the alias of the certificate to be used for signing.

keyring - the key ring, as a wrapper and helper to acces the key store.

provider - the security provider supporting and exposing the key store capabilities.

Throws:

CryptoException - if any of the input parameters is null.

Method Detail

getAlias

protected String getAlias()

Returns the alias of the certificate to be used for signing.

Returns:

the alias of the certificate to be used for signing.

getKeyRing

protected KeyRing getKeyRing()

Returns the key ring containing the signature key.

Returns:

the key ring containing the signature key.

getProvider

protected Provider getProvider()

Returns the security provider backing up the key store.

Returns:

the security provider backing up the key store.

isEncapsulateData

public boolean isEncapsulateData()

Returns whether the data is going to be encapsulated along with the signature.

Returns:

whether the data is going to be encapsulated along with the signature.

initialise

public abstract void initialise()
                         throws CryptoException

Initialises the object.

Throws:

CryptoException - if anything went wrong accessing, opening or interpreting the keystore.

sign

public abstract byte[] sign(byte[] data)
                     throws CryptoException

Signs the given set of data.

Parameters:

data - the data to be signed.

Returns:

the signed data as a byte array.

Throws:

CryptoException

verify

public abstract boolean verify(byte[] signed)
                        throws CryptoException

Verifies the signature of the given set of encapsulated data.

Parameters:

signed - the encapsulated data.

Returns:

whether the signature is valid.

Throws:

CryptoException

verify

public abstract boolean verify(byte[] signed,
             byte[] data)
                        throws CryptoException

Verifies the signature of the given set of detached data.

Parameters:

signed - the detached data whose signature is to be verified.

data - the original, plain text data.

Returns:

Throws:

CryptoException