public static AsymmetricKeyParameter CreateKey( PrivateKeyInfo keyInfo) { AlgorithmIdentifier algID = keyInfo.PrivateKeyAlgorithm; DerObjectIdentifier algOid = algID.Algorithm; // TODO See RSAUtil.isRsaOid in Java build if (algOid.Equals(PkcsObjectIdentifiers.RsaEncryption) || algOid.Equals(X509ObjectIdentifiers.IdEARsa) || algOid.Equals(PkcsObjectIdentifiers.IdRsassaPss) || algOid.Equals(PkcsObjectIdentifiers.IdRsaesOaep)) { RsaPrivateKeyStructure keyStructure = RsaPrivateKeyStructure.GetInstance(keyInfo.ParsePrivateKey()); return(new RsaPrivateCrtKeyParameters( keyStructure.Modulus, keyStructure.PublicExponent, keyStructure.PrivateExponent, keyStructure.Prime1, keyStructure.Prime2, keyStructure.Exponent1, keyStructure.Exponent2, keyStructure.Coefficient)); } // TODO? // else if (algOid.Equals(X9ObjectIdentifiers.DHPublicNumber)) else if (algOid.Equals(PkcsObjectIdentifiers.DhKeyAgreement)) { DHParameter para = new DHParameter( Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object())); DerInteger derX = (DerInteger)keyInfo.ParsePrivateKey(); BigInteger lVal = para.L; int l = lVal == null ? 0 : lVal.IntValue; DHParameters dhParams = new DHParameters(para.P, para.G, null, l); return(new DHPrivateKeyParameters(derX.Value, dhParams, algOid)); } else if (algOid.Equals(OiwObjectIdentifiers.ElGamalAlgorithm)) { ElGamalParameter para = new ElGamalParameter( Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object())); DerInteger derX = (DerInteger)keyInfo.ParsePrivateKey(); return(new ElGamalPrivateKeyParameters( derX.Value, new ElGamalParameters(para.P, para.G))); } else if (algOid.Equals(X9ObjectIdentifiers.IdDsa)) { DerInteger derX = (DerInteger)keyInfo.ParsePrivateKey(); Asn1Encodable ae = algID.Parameters; DsaParameters parameters = null; if (ae != null) { DsaParameter para = DsaParameter.GetInstance(ae.ToAsn1Object()); parameters = new DsaParameters(para.P, para.Q, para.G); } return(new DsaPrivateKeyParameters(derX.Value, parameters)); } else if (algOid.Equals(X9ObjectIdentifiers.IdECPublicKey)) { X962Parameters para = new X962Parameters(algID.Parameters.ToAsn1Object()); X9ECParameters x9; if (para.IsNamedCurve) { x9 = ECKeyPairGenerator.FindECCurveByOid((DerObjectIdentifier)para.Parameters); } else { x9 = new X9ECParameters((Asn1Sequence)para.Parameters); } ECPrivateKeyStructure ec = ECPrivateKeyStructure.GetInstance(keyInfo.ParsePrivateKey()); BigInteger d = ec.GetKey(); if (para.IsNamedCurve) { return(new ECPrivateKeyParameters("EC", d, (DerObjectIdentifier)para.Parameters)); } ECDomainParameters dParams = new ECDomainParameters(x9.Curve, x9.G, x9.N, x9.H, x9.GetSeed()); return(new ECPrivateKeyParameters(d, dParams)); } else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x2001)) { Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters( Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object())); ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet); if (ecP == null) { throw new ArgumentException("Unrecognized curve OID for GostR3410x2001 private key"); } Asn1Object privKey = keyInfo.ParsePrivateKey(); ECPrivateKeyStructure ec; if (privKey is DerInteger) { ec = new ECPrivateKeyStructure(ecP.N.BitLength, ((DerInteger)privKey).PositiveValue); } else { ec = ECPrivateKeyStructure.GetInstance(privKey); } return(new ECPrivateKeyParameters("ECGOST3410", ec.GetKey(), gostParams.PublicKeyParamSet)); } else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x94)) { Gost3410PublicKeyAlgParameters gostParams = Gost3410PublicKeyAlgParameters.GetInstance(algID.Parameters); Asn1Object privKey = keyInfo.ParsePrivateKey(); BigInteger x; if (privKey is DerInteger) { x = DerInteger.GetInstance(privKey).PositiveValue; } else { x = new BigInteger(1, Arrays.Reverse(Asn1OctetString.GetInstance(privKey).GetOctets())); } return(new Gost3410PrivateKeyParameters(x, gostParams.PublicKeyParamSet)); } else if (algOid.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_256) || algOid.Equals(RosstandartObjectIdentifiers.id_tc26_gost_3410_12_512)) { Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters( Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object())); ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet); if (ecP == null) { throw new ArgumentException("Unrecognized curve OID for id_tc26_gost_3410_12_256 private key"); } byte[] privKeyBytes = keyInfo.PrivateKeyGetOctets(); BigInteger x = new BigInteger(1, Arrays.Reverse(privKeyBytes)); ECPrivateKeyStructure ec = new ECPrivateKeyStructure(ecP.N.BitLength, x); return(new ECPrivateKeyParameters("ECGOST3410", ec.GetKey(), gostParams.PublicKeyParamSet)); } else { throw new SecurityUtilityException("algorithm identifier in key not recognised"); } }