iaik.security.rsa
Class SSLRSASignature

java.lang.Object
  |
  +--java.security.SignatureSpi
        |
        +--java.security.Signature
              |
              +--iaik.security.rsa.SSLRSASignature

public class SSLRSASignature

extends Signature

THIS CLASS IS OUTDATED AND SHOULD NOT BE USED ANY LONGER. It was originally written for use by the iSaSiLk library, but it is not used for this purpose any longer. It will probably be removed in a future release, if you still need it please contact jce-info@iaik.at.

This class implements a special form of a RSA Signature as used within the Secure Sockets Layer (SSL v3.0) protocol.

SSL handles digital signatures by either using the Digital Signature Algorithm (DSA) or a RSA based method. This class implements the RSA version od SSL digital signing, where the SHA and MD5 hash algorithms are used to form 36-byte structure, which subsequently is signed (encrypted with the RSA private key).

In contrast to Md5RSASignature and ShaRSASignature this class not only calls the superclass constructor specifying the hash algorithm to be used. This class overrides all the methods of the superclass according to the particular signature requirements of the SSLv3 protocol.

The general proceeding for signing a message (e.g. build up of client_hello_random + server_hello_random + params) or verifying a signature follows the common guidelines prescribing three steps to be performed:

• First an instance of the desired signature algorithm has to be created using a proper getInstance method, e.g.:

   Signature ssl_rsa = Signature.getInstance("SSL/RSA");
   

• Second, the Signature object just created has to be properly initialized for signing a message respectively verifying a signature using a RSA private respectively RSA public key, e.g.:
  • Initialize for Signing: ssl_rsa.initSign(rsaPrivateKey);
  • Initialize for Verifying: ssl_rsa.initVerify(rsaPublicKey);

• Finally, if the Signature object has been initialized for signing, the data to be signed is supplied to it and subsequently the signature is created by calling the sign method returning the signature as DER encoded byte array. Otherwise, if the Signature object has been initialized for verifying, first the data to be verified is supplied to the Signature object, and subsequently the signature is verified by calling the verify method, supplied with the DER encoded byte array holding the corresponding signature:
  • Supply the data to be signed, and subsequently sign it:

     ssl_rsa.update(data);
     byte[] signature = ssl_rsa.sign();
     

  • Supply the data to be verified, and verify the signature:

     ssl_rsa.update(data);
     System.out.println("Signature " + (ssl_rsa.verify(signature) ? "correct!" : "not correct!"));
     

See Also:

RSASignature, ShaRSASignature, Md5RSASignature, Signature, Md5, SHA

Field Summary

protected MessageDigest	md5 The first message digest used to MD5-based hash the data.
protected MessageDigest	sha The second message digest used to SHA-based hash the data.

Fields inherited from class java.security.Signature

SIGN, state, UNINITIALIZED, VERIFY

Fields inherited from class java.security.SignatureSpi

appRandom

Constructor Summary

SSLRSASignature()
The default constructor.

Method Summary

protected java.lang.Object	engineGetParameter(java.lang.String param) This method is not implemented and only throws an InvalidParameterException
protected void	engineInitSign(PrivateKey pk) SPI: Initializes this signature object with the given RSA private key for going to sign some data.
protected void	engineInitVerify(PublicKey pk) SPI: Initializes this signature object with the given RSA public key for performing a signature verification.
protected void	engineSetParameter(java.lang.String param, java.lang.Object value) This method is not implemented and only throws an InvalidParameterException
protected byte[]	engineSign() SPI: Returns a byte array holding the signature resulting from all already performed data update operations.
protected void	engineUpdate(byte b) SPI: Updates the data to be signed or verified with the specified byte.
protected void	engineUpdate(byte[] b, int off, int len) SPI: Updates the data to be signed or verified with the specified number of bytes, beginning at the specified offset within the given byte array.
protected boolean	engineVerify(byte[] sigBytes) Verifies the given signature of a message according to SSL v3.0.

Methods inherited from class java.security.Signature

clone, getAlgorithm, getInstance, getInstance, getParameter, getProvider, initSign, initSign, initVerify, setParameter, setParameter, sign, sign, toString, update, update, update, verify

Methods inherited from class java.security.SignatureSpi

engineInitSign, engineSetParameter, engineSign

Methods inherited from class java.lang.Object

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

Field Detail

md5

protected MessageDigest md5

The first message digest used to MD5-based hash the data.

sha

protected MessageDigest sha

The second message digest used to SHA-based hash the data.

Constructor Detail

SSLRSASignature

public SSLRSASignature()
                throws NoSuchAlgorithmException

The default constructor. Creates a new SSL/RSA Signature object.

Throws:

NoSuchAlgorithmException - if there is no implementation for MD5 or SHA

Method Detail

engineInitVerify

protected void engineInitVerify(PublicKey pk)
                         throws InvalidKeyException

SPI: Initializes this signature object with the given RSA public key for performing a signature verification.

Overrides:

engineInitVerify in class SignatureSpi

Parameters:

publicKey - the RSA public key belonging to the RSA private key that has been used for signing.

Throws:

InvalidKeyException - if a key encoding error occurs

engineInitSign

protected void engineInitSign(PrivateKey pk)
                       throws InvalidKeyException

SPI: Initializes this signature object with the given RSA private key for going to sign some data.

Overrides:

engineInitSign in class SignatureSpi

Parameters:

privateKey - the RSA private key to be used for signing.

Throws:

InvalidKeyException - if a key encoding error occurs

engineSign

protected byte[] engineSign()
                     throws SignatureException

SPI: Returns a byte array holding the signature resulting from all already performed data update operations. The signature is returned as defined in SSL v3.0.

According to SSLv3 the data is digested with both Md5 and SHA algorithms before encrypting the result using the RSA algorithm with PKCS#1 padding.

Overrides:

engineSign in class SignatureSpi

Returns:

a byte array holding the signature

Throws:

SignatureException - if an error occurs when creating the signature

engineVerify

protected boolean engineVerify(byte[] sigBytes)
                        throws SignatureException

Verifies the given signature of a message according to SSL v3.0.

According to SSLv3 the data is digested with both Md5 and SHA algorithms before decrypting it using the RSA algorithm.

Overrides:

engineVerify in class SignatureSpi

Parameters:

sigBytes - the signature bytes to be verified

Returns:

true if signature is OK, false if not

Throws:

SignatureException - if an error occurs when verifying the signature

engineUpdate

protected void engineUpdate(byte b)

SPI: Updates the data to be signed or verified with the specified byte.

Overrides:

engineUpdate in class SignatureSpi

Parameters:

b - the byte to update.

engineUpdate

protected void engineUpdate(byte[] b,
                            int off,
                            int len)

SPI: Updates the data to be signed or verified with the specified number of bytes, beginning at the specified offset within the given byte array.

Overrides:

engineUpdate in class SignatureSpi

Parameters:

data - the byte array holding the data to be used for this update operation.

off - the offset, indicating the start position within the given byte array.

len - the number of bytes to be obtained from the given byte array, starting at the given position.

engineSetParameter

protected void engineSetParameter(java.lang.String param,
                                  java.lang.Object value)
                           throws InvalidParameterException

This method is not implemented and only throws an InvalidParameterException

Overrides:

engineSetParameter in class SignatureSpi

Throws:

InvalidParameterException - This Method is not supported

engineGetParameter

protected java.lang.Object engineGetParameter(java.lang.String param)
                                       throws InvalidParameterException

This method is not implemented and only throws an InvalidParameterException

Overrides:

engineGetParameter in class SignatureSpi

Throws:

InvalidParameterException - This Method is not supported