private KeyParameter CalculateAgreedWrapKey(
string wrapAlg,
AsymmetricKeyParameter senderPublicKey,
AsymmetricKeyParameter receiverPrivateKey)
{
DerObjectIdentifier agreeAlgID = keyEncAlg.Algorithm;
ICipherParameters senderPublicParams = senderPublicKey;
ICipherParameters receiverPrivateParams = receiverPrivateKey;
if (agreeAlgID.Id.Equals(CmsEnvelopedGenerator.ECMqvSha1Kdf))
{
byte[] ukmEncoding = info.UserKeyingMaterial.GetOctets();
MQVuserKeyingMaterial ukm = MQVuserKeyingMaterial.GetInstance(
Asn1Object.FromByteArray(ukmEncoding));
AsymmetricKeyParameter ephemeralKey = GetPublicKeyFromOriginatorPublicKey(
receiverPrivateKey, ukm.EphemeralPublicKey);
senderPublicParams = new MqvPublicParameters(
(ECPublicKeyParameters)senderPublicParams,
(ECPublicKeyParameters)ephemeralKey);
receiverPrivateParams = new MqvPrivateParameters(
(ECPrivateKeyParameters)receiverPrivateParams,
(ECPrivateKeyParameters)receiverPrivateParams);
}
IBasicAgreement agreement = AgreementUtilities.GetBasicAgreementWithKdf(
agreeAlgID, wrapAlg);
agreement.Init(receiverPrivateParams);
BigInteger agreedValue = agreement.CalculateAgreement(senderPublicParams);
int wrapKeySize = GeneratorUtilities.GetDefaultKeySize(wrapAlg) / 8;
byte[] wrapKeyBytes = X9IntegerConverter.IntegerToBytes(agreedValue, wrapKeySize);
return(ParameterUtilities.CreateKeyParameter(wrapAlg, wrapKeyBytes));
}
private KeyParameter CalculateAgreedWrapKey(string wrapAlg, AsymmetricKeyParameter senderPublicKey, AsymmetricKeyParameter receiverPrivateKey)
{
DerObjectIdentifier objectID = this.keyEncAlg.ObjectID;
ICipherParameters cipherParameters = senderPublicKey;
ICipherParameters cipherParameters2 = receiverPrivateKey;
if (objectID.Id.Equals(CmsEnvelopedGenerator.ECMqvSha1Kdf))
{
byte[] octets = this.info.UserKeyingMaterial.GetOctets();
MQVuserKeyingMaterial instance = MQVuserKeyingMaterial.GetInstance(Asn1Object.FromByteArray(octets));
AsymmetricKeyParameter publicKeyFromOriginatorPublicKey = this.GetPublicKeyFromOriginatorPublicKey(receiverPrivateKey, instance.EphemeralPublicKey);
cipherParameters = new MqvPublicParameters((ECPublicKeyParameters)cipherParameters, (ECPublicKeyParameters)publicKeyFromOriginatorPublicKey);
cipherParameters2 = new MqvPrivateParameters((ECPrivateKeyParameters)cipherParameters2, (ECPrivateKeyParameters)cipherParameters2);
}
IBasicAgreement basicAgreementWithKdf = AgreementUtilities.GetBasicAgreementWithKdf(objectID, wrapAlg);
basicAgreementWithKdf.Init(cipherParameters2);
BigInteger s = basicAgreementWithKdf.CalculateAgreement(cipherParameters);
int qLength = GeneratorUtilities.GetDefaultKeySize(wrapAlg) / 8;
byte[] keyBytes = X9IntegerConverter.IntegerToBytes(s, qLength);
return(ParameterUtilities.CreateKeyParameter(wrapAlg, keyBytes));
}