/**
* Return the maximum size for an input block to this engine.
* For RSA this is always one byte less than the key size on
* encryption, and the same length as the key size on decryption.
*
* @return maximum size for an input block.
*/
public int getInputBlockSize()
{
int bitSize = key.getModulus().bitLength();
if (forEncryption)
{
return((bitSize + 7) / 8 - 1);
}
else
{
return((bitSize + 7) / 8);
}
}
public virtual void init(bool forSigning, CipherParameters param)
{
RSAKeyParameters kParam = null;
if (param is ParametersWithRandom)
{
ParametersWithRandom p = (ParametersWithRandom)param;
kParam = (RSAKeyParameters)p.getParameters();
random = p.getRandom();
}
else
{
kParam = (RSAKeyParameters)param;
if (forSigning)
{
random = new SecureRandom();
}
}
cipher.init(forSigning, kParam);
emBits = kParam.getModulus().bitLength() - 1;
block = new byte[(emBits + 7) / 8];
reset();
}
public ScrambledKeyPair(AsymmetricCipherKeyPair pPair)
{
_pair = pPair;
AsymmetricKeyParameter publicKey = pPair.getPublic();
RSAKeyParameters rsaKeyParameters = publicKey as RSAKeyParameters;
if (rsaKeyParameters != null)
{
ScrambledModulus = ScrambleModulus(rsaKeyParameters.getModulus());
}
PrivateKey = pPair.getPrivate();
}
public virtual void init(bool forSigning, CipherParameters param)
{
RSAKeyParameters kParam = (RSAKeyParameters)param;
cipher.init(forSigning, kParam);
keyBits = kParam.getModulus().bitLength();
block = new byte[(keyBits + 7) / 8];
mBuf = new byte[block.Length - 1];
reset();
}
/// <summary> Initialise the signer.
///
/// </summary>
/// <param name="forSigning">true if for signing, false if for verification.
/// </param>
/// <param name="param">parameters for signature generation/verification. If the
/// parameters are for generation they should be a ParametersWithRandom,
/// a ParametersWithSalt, or just an RSAKeyParameters object. If RSAKeyParameters
/// are passed in a SecureRandom will be created.
/// </param>
/// <exception cref="ArgumentException"> IllegalArgumentException if wrong parameter type or a fixed
/// salt is passed in which is the wrong length.
/// </exception>
public virtual void init(bool forSigning, CipherParameters param)
{
RSAKeyParameters kParam = null;
int lengthOfSalt = saltLength;
if (param is ParametersWithRandom)
{
ParametersWithRandom p = (ParametersWithRandom)param;
kParam = (RSAKeyParameters)p.getParameters();
random = p.getRandom();
}
else if (param is ParametersWithSalt)
{
ParametersWithSalt p = (ParametersWithSalt)param;
kParam = (RSAKeyParameters)p.getParameters();
standardSalt = p.getSalt();
lengthOfSalt = standardSalt.Length;
}
else
{
kParam = (RSAKeyParameters)param;
if (forSigning)
{
random = new SecureRandom();
}
}
cipher.init(forSigning, kParam);
keyBits = kParam.getModulus().bitLength();
block = new byte[(keyBits + 7) / 8];
if (trailer == TRAILER_IMPLICIT)
{
mBuf = new byte[block.Length - digest.getDigestSize() - lengthOfSalt - 1 - 1];
}
else
{
mBuf = new byte[block.Length - digest.getDigestSize() - lengthOfSalt - 1 - 2];
}
reset();
}
public void init(
bool forEncryption,
CipherParameters param)
{
RSAKeyParameters kParam = null;
if (typeof(ParametersWithRandom).IsInstanceOfType(param))
{
ParametersWithRandom rParam = (ParametersWithRandom)param;
kParam = (RSAKeyParameters)rParam.getParameters();
}
else
{
kParam = (RSAKeyParameters)param;
}
engine.init(forEncryption, kParam);
bitSize = kParam.getModulus().bitLength();
this.forEncryption = forEncryption;
}
/// <summary>
/// Create a Subject Public Key Info object for a given public key.
/// </summary>
/// <param name="key">One of ElGammalPublicKeyParameters, DSAPublicKeyParameter, DHPublicKeyParameters, RSAKeyParameters or ECPublicKeyParameters</param>
/// <returns>A subject public key info object.</returns>
/// <exception cref="Exception">Throw exception if object provided is not one of the above.</exception>
public static SubjectPublicKeyInfo CreateSubjectPublicKeyInfo(AsymmetricKeyParameter key)
{
if (key.isPrivate())
{
throw (new Exception("Private key passed - public key expected."));
}
if (key is ElGamalPublicKeyParameters)
{
ElGamalPublicKeyParameters _key = (ElGamalPublicKeyParameters)key;
SubjectPublicKeyInfo info =
new SubjectPublicKeyInfo(
new AlgorithmIdentifier(
OIWObjectIdentifiers.elGamalAlgorithm,
new ElGamalParameter(
_key.getParameters().getP(),
_key.getParameters().getG()
).toASN1Object()), new DERInteger(_key.getY()));
return(info);
}
if (key is DSAPublicKeyParameters)
{
DSAPublicKeyParameters _key = (DSAPublicKeyParameters)key;
SubjectPublicKeyInfo info =
new SubjectPublicKeyInfo(
new AlgorithmIdentifier(
X9ObjectIdentifiers.id_dsa,
new DSAParameter(_key.getParameters().getP(), _key.getParameters().getQ(), _key.getParameters().getG()).toASN1Object()),
new DERInteger(_key.getY())
);
return(info);
}
if (key is DHPublicKeyParameters)
{
DHPublicKeyParameters _key = (DHPublicKeyParameters)key;
SubjectPublicKeyInfo info = new SubjectPublicKeyInfo(
new AlgorithmIdentifier(X9ObjectIdentifiers.dhpublicnumber,
new DHParameter(_key.getParameters().getP(),
_key.getParameters().getG(),
_key.getParameters().getJ()).toASN1Object()), new DERInteger(_key.getY()));
return(info);
} // End of DH
if (key is RSAKeyParameters)
{
RSAKeyParameters _key = (RSAKeyParameters)key;
if (_key.isPrivate())
{
throw (new Exception("Private RSA Key provided."));
}
SubjectPublicKeyInfo info = new SubjectPublicKeyInfo(new AlgorithmIdentifier(PKCSObjectIdentifiers.rsaEncryption, new DERNull()), new RSAPublicKeyStructure(_key.getModulus(), _key.getExponent()).toASN1Object());
return(info);
} // End of RSA.
if (key is ECPublicKeyParameters)
{
ECPublicKeyParameters _key = (ECPublicKeyParameters)key;
X9ECParameters ecP = new X9ECParameters(
_key.getParameters().getCurve(),
_key.getParameters().getG(),
_key.getParameters().getN(),
_key.getParameters().getH(),
_key.getParameters().getSeed());
X962Parameters x962 = new X962Parameters(ecP);
ASN1OctetString p = (ASN1OctetString)(new X9ECPoint(_key.getQ()).toASN1Object());
SubjectPublicKeyInfo info = new SubjectPublicKeyInfo(new AlgorithmIdentifier(X9ObjectIdentifiers.id_ecPublicKey, x962.toASN1Object()), p.getOctets());
return(info);
} // End of EC
throw (new Exception("Class provided no convertable:" + key.GetType()));
}
