Inheritance: Org.BouncyCastle.Asn1.Asn1Encodable
		public static AsymmetricKeyParameter CreateKey(
			PrivateKeyInfo keyInfo)
        {
            AlgorithmIdentifier algID = keyInfo.AlgorithmID;
			DerObjectIdentifier algOid = algID.ObjectID;

			// 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 = new RsaPrivateKeyStructure(
					Asn1Sequence.GetInstance(keyInfo.PrivateKey));

				return new RsaPrivateCrtKeyParameters(
					keyStructure.Modulus,
					keyStructure.PublicExponent,
					keyStructure.PrivateExponent,
					keyStructure.Prime1,
					keyStructure.Prime2,
					keyStructure.Exponent1,
					keyStructure.Exponent2,
					keyStructure.Coefficient);
			}
			else if (algOid.Equals(PkcsObjectIdentifiers.DhKeyAgreement))
			{
				DHParameter para = new DHParameter(
					Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
				DerInteger derX = (DerInteger)keyInfo.PrivateKey;

				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);
			}
			else if (algOid.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
			{
				ElGamalParameter  para = new ElGamalParameter(
					Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
				DerInteger derX = (DerInteger)keyInfo.PrivateKey;

				return new ElGamalPrivateKeyParameters(
					derX.Value,
					new ElGamalParameters(para.P, para.G));
			}
			else if (algOid.Equals(X9ObjectIdentifiers.IdDsa))
			{
				DerInteger derX = (DerInteger) keyInfo.PrivateKey;
				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 ecP;

				if (para.IsNamedCurve)
				{
					// TODO ECGost3410NamedCurves support (returns ECDomainParameters though)

					DerObjectIdentifier oid = (DerObjectIdentifier) para.Parameters;
					ecP = X962NamedCurves.GetByOid(oid);

					if (ecP == null)
					{
						ecP = SecNamedCurves.GetByOid(oid);

						if (ecP == null)
						{
							ecP = NistNamedCurves.GetByOid(oid);

							if (ecP == null)
							{
								ecP = TeleTrusTNamedCurves.GetByOid(oid);
							}
						}
					}
				}
				else
				{
					ecP = new X9ECParameters((Asn1Sequence) para.Parameters);
				}

				ECDomainParameters dParams = new ECDomainParameters(
					ecP.Curve,
					ecP.G,
					ecP.N,
					ecP.H,
					ecP.GetSeed());

				ECPrivateKeyStructure ec = new ECPrivateKeyStructure(
					Asn1Sequence.GetInstance(keyInfo.PrivateKey));

				return new ECPrivateKeyParameters(ec.GetKey(), dParams);
			}
			else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x2001))
			{
				Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
					Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));

				ECPrivateKeyStructure ec = new ECPrivateKeyStructure(
					Asn1Sequence.GetInstance(keyInfo.PrivateKey));

				ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet);

				if (ecP == null)
					return null;

				return new ECPrivateKeyParameters(ec.GetKey(), gostParams.PublicKeyParamSet);
			}
			else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x94))
			{
				Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
					Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));

				DerOctetString derX = (DerOctetString) keyInfo.PrivateKey;
				byte[] keyEnc = derX.GetOctets();
				byte[] keyBytes = new byte[keyEnc.Length];

				for (int i = 0; i != keyEnc.Length; i++)
				{
					keyBytes[i] = keyEnc[keyEnc.Length - 1 - i]; // was little endian
				}

				BigInteger x = new BigInteger(1, keyBytes);

				return new Gost3410PrivateKeyParameters(x, gostParams.PublicKeyParamSet);
			}
			else
			{
				throw new SecurityUtilityException("algorithm identifier in key not recognised");
			}
        }
        public static AsymmetricKeyParameter CreateKey(
			PrivateKeyInfo keyInfo)
        {
            AlgorithmIdentifier algID = keyInfo.AlgorithmID;
            if (algID.ObjectID.Equals(PkcsObjectIdentifiers.RsaEncryption))
            {
                RsaPrivateKeyStructure keyStructure = new RsaPrivateKeyStructure(
                    (Asn1Sequence)keyInfo.PrivateKey);
                return (new RsaPrivateCrtKeyParameters(
                    keyStructure.Modulus,
                    keyStructure.PublicExponent,
                    keyStructure.PrivateExponent,
                    keyStructure.Prime1,
                    keyStructure.Prime2,
                    keyStructure.Exponent1,
                    keyStructure.Exponent2,
                    keyStructure.Coefficient));
            }
            else if (algID.ObjectID.Equals(PkcsObjectIdentifiers.DhKeyAgreement))
            {
                DHParameter para = new DHParameter((Asn1Sequence)algID.Parameters);
                DerInteger derX = (DerInteger)keyInfo.PrivateKey;
                return new DHPrivateKeyParameters(derX.Value, new DHParameters(para.P, para.G));
            }
            else if (algID.ObjectID.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
            {
                ElGamalParameter  para = new ElGamalParameter((Asn1Sequence)algID.Parameters);
                DerInteger derX = (DerInteger)keyInfo.PrivateKey;
                return new ElGamalPrivateKeyParameters(derX.Value, new ElGamalParameters(para.P, para.G));
            }
            else if (algID.ObjectID.Equals(X9ObjectIdentifiers.IdDsa))
            {
                DsaParameter para = DsaParameter.GetInstance(algID.Parameters);
                DerInteger derX = (DerInteger) keyInfo.PrivateKey;
                return new DsaPrivateKeyParameters(derX.Value, new DsaParameters(para.P, para.Q, para.G));
            }
            else if (algID.ObjectID.Equals(X9ObjectIdentifiers.IdECPublicKey))
            {
                X962Parameters para = new X962Parameters((Asn1Object)algID.Parameters);
                ECDomainParameters dParams = null;

                if (para.IsNamedCurve)
                {
                    DerObjectIdentifier oid = (DerObjectIdentifier) para.Parameters;
                    X9ECParameters ecP = X962NamedCurves.GetByOid(oid);

                    if (ecP == null)
                    {
                        ecP = SecNamedCurves.GetByOid(oid);

                        if (ecP == null)
                        {
                            ecP = NistNamedCurves.GetByOid(oid);
                        }
                    }

                    dParams = new ECDomainParameters(
                        ecP.Curve,
                        ecP.G,
                        ecP.N,
                        ecP.H,
                        ecP.GetSeed());
                }
                else
                {
                    X9ECParameters ecP = new X9ECParameters(
                        (Asn1Sequence) para.Parameters);
                    dParams = new ECDomainParameters(
                        ecP.Curve,
                        ecP.G,
                        ecP.N,
                        ecP.H,
                        ecP.GetSeed());
                }

                ECPrivateKeyStructure ec = new ECPrivateKeyStructure((Asn1Sequence)keyInfo.PrivateKey);

                return new ECPrivateKeyParameters(ec.GetKey(), dParams);
            }
            else if (algID.ObjectID.Equals(CryptoProObjectIdentifiers.GostR3410x2001))
            {
                throw new NotImplementedException();
            }
            else if (algID.ObjectID.Equals(CryptoProObjectIdentifiers.GostR3410x94))
            {
                Gost3410PublicKeyAlgParameters algParams = new Gost3410PublicKeyAlgParameters(
                    (Asn1Sequence) algID.Parameters);

                DerOctetString derX = (DerOctetString) keyInfo.PrivateKey;
                byte[] keyEnc = derX.GetOctets();
                byte[] keyBytes = new byte[keyEnc.Length];

                for (int i = 0; i != keyEnc.Length; i++)
                {
                    keyBytes[i] = keyEnc[keyEnc.Length - 1 - i]; // was little endian
                }

                BigInteger x = new BigInteger(1, keyBytes);

                return new Gost3410PrivateKeyParameters(x, algParams.PublicKeyParamSet);
            }
            else
            {
                throw new SecurityUtilityException("algorithm identifier in key not recognised");
            }
        }
Exemple #3
0
        public static AsymmetricKeyParameter CreateKey(
            SubjectPublicKeyInfo keyInfo)
        {
            AlgorithmIdentifier algID = keyInfo.AlgorithmID;
            DerObjectIdentifier algOid = algID.ObjectID;

            // TODO See RSAUtil.isRsaOid in Java build
            if (algOid.Equals(PkcsObjectIdentifiers.RsaEncryption)
                || algOid.Equals(X509ObjectIdentifiers.IdEARsa)
                || algOid.Equals(PkcsObjectIdentifiers.IdRsassaPss)
                || algOid.Equals(PkcsObjectIdentifiers.IdRsaesOaep))
            {
                RsaPublicKeyStructure pubKey = RsaPublicKeyStructure.GetInstance(
                    keyInfo.GetPublicKey());

                return new RsaKeyParameters(false, pubKey.Modulus, pubKey.PublicExponent);
            }
            else if (algOid.Equals(X9ObjectIdentifiers.DHPublicNumber))
            {
                Asn1Sequence seq = Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object());

                DHPublicKey dhPublicKey = DHPublicKey.GetInstance(keyInfo.GetPublicKey());

                BigInteger y = dhPublicKey.Y.Value;

                if (IsPkcsDHParam(seq))
                    return ReadPkcsDHParam(algOid, y, seq);

                DHDomainParameters dhParams = DHDomainParameters.GetInstance(seq);

                BigInteger p = dhParams.P.Value;
                BigInteger g = dhParams.G.Value;
                BigInteger q = dhParams.Q.Value;

                BigInteger j = null;
                if (dhParams.J != null)
                {
                    j = dhParams.J.Value;
                }

                DHValidationParameters validation = null;
                DHValidationParms dhValidationParms = dhParams.ValidationParms;
                if (dhValidationParms != null)
                {
                    byte[] seed = dhValidationParms.Seed.GetBytes();
                    BigInteger pgenCounter = dhValidationParms.PgenCounter.Value;

                    // TODO Check pgenCounter size?

                    validation = new DHValidationParameters(seed, pgenCounter.IntValue);
                }

                return new DHPublicKeyParameters(y, new DHParameters(p, g, q, j, validation));
            }
            else if (algOid.Equals(PkcsObjectIdentifiers.DhKeyAgreement))
            {
                Asn1Sequence seq = Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object());

                DerInteger derY = (DerInteger) keyInfo.GetPublicKey();

                return ReadPkcsDHParam(algOid, derY.Value, seq);
            }
            else if (algOid.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
            {
                ElGamalParameter para = new ElGamalParameter(
                    Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
                DerInteger derY = (DerInteger) keyInfo.GetPublicKey();

                return new ElGamalPublicKeyParameters(
                    derY.Value,
                    new ElGamalParameters(para.P, para.G));
            }
            else if (algOid.Equals(X9ObjectIdentifiers.IdDsa)
                || algOid.Equals(OiwObjectIdentifiers.DsaWithSha1))
            {
                DerInteger derY = (DerInteger) keyInfo.GetPublicKey();
                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 DsaPublicKeyParameters(derY.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);
                }

                Asn1OctetString key = new DerOctetString(keyInfo.PublicKeyData.GetBytes());
                X9ECPoint derQ = new X9ECPoint(x9.Curve, key);
                ECPoint q = derQ.Point;

                if (para.IsNamedCurve)
                {
                    return new ECPublicKeyParameters("EC", q, (DerObjectIdentifier)para.Parameters);
                }

                ECDomainParameters dParams = new ECDomainParameters(x9.Curve, x9.G, x9.N, x9.H, x9.GetSeed());
                return new ECPublicKeyParameters(q, dParams);
            }
            else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x2001))
            {
                Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
                    (Asn1Sequence) algID.Parameters);

                Asn1OctetString key;
                try
                {
                    key = (Asn1OctetString) keyInfo.GetPublicKey();
                }
                catch (IOException)
                {
                    throw new ArgumentException("invalid info structure in GOST3410 public key");
                }

                byte[] keyEnc = key.GetOctets();
                byte[] x = new byte[32];
                byte[] y = new byte[32];

                for (int i = 0; i != y.Length; i++)
                {
                    x[i] = keyEnc[32 - 1 - i];
                }

                for (int i = 0; i != x.Length; i++)
                {
                    y[i] = keyEnc[64 - 1 - i];
                }

                ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet);

                if (ecP == null)
                    return null;

                ECPoint q = ecP.Curve.CreatePoint(new BigInteger(1, x), new BigInteger(1, y));

                return new ECPublicKeyParameters("ECGOST3410", q, gostParams.PublicKeyParamSet);
            }
            else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x94))
            {
                Gost3410PublicKeyAlgParameters algParams = new Gost3410PublicKeyAlgParameters(
                    (Asn1Sequence) algID.Parameters);

                DerOctetString derY;
                try
                {
                    derY = (DerOctetString) keyInfo.GetPublicKey();
                }
                catch (IOException)
                {
                    throw new ArgumentException("invalid info structure in GOST3410 public key");
                }

                byte[] keyEnc = derY.GetOctets();
                byte[] keyBytes = new byte[keyEnc.Length];

                for (int i = 0; i != keyEnc.Length; i++)
                {
                    keyBytes[i] = keyEnc[keyEnc.Length - 1 - i]; // was little endian
                }

                BigInteger y = new BigInteger(1, keyBytes);

                return new Gost3410PublicKeyParameters(y, algParams.PublicKeyParamSet);
            }
            else
            {
                throw new SecurityUtilityException("algorithm identifier in key not recognised: " + algOid);
            }
        }
		public static AsymmetricKeyParameter CreateKey(
			SubjectPublicKeyInfo keyInfo)
        {
            AlgorithmIdentifier algID = keyInfo.AlgorithmID;
			DerObjectIdentifier algOid = algID.ObjectID;

			// TODO See RSAUtil.isRsaOid in Java build
			if (algOid.Equals(PkcsObjectIdentifiers.RsaEncryption)
				|| algOid.Equals(X509ObjectIdentifiers.IdEARsa)
				|| algOid.Equals(PkcsObjectIdentifiers.IdRsassaPss)
				|| algOid.Equals(PkcsObjectIdentifiers.IdRsaesOaep))
			{
				RsaPublicKeyStructure pubKey = RsaPublicKeyStructure.GetInstance(
					keyInfo.GetPublicKey());

				return new RsaKeyParameters(false, pubKey.Modulus, pubKey.PublicExponent);
			}
			else if (algOid.Equals(PkcsObjectIdentifiers.DhKeyAgreement)
				|| algOid.Equals(X9ObjectIdentifiers.DHPublicNumber))
			{
				DHParameter para = new DHParameter(
					Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
				DerInteger derY = (DerInteger) keyInfo.GetPublicKey();

				BigInteger lVal = para.L;
				int l = lVal == null ? 0 : lVal.IntValue;
				DHParameters dhParams = new DHParameters(para.P, para.G, null, l);

				return new DHPublicKeyParameters(derY.Value, dhParams);
			}
			else if (algOid.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
			{
				ElGamalParameter para = new ElGamalParameter(
					Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
				DerInteger derY = (DerInteger) keyInfo.GetPublicKey();

				return new ElGamalPublicKeyParameters(
					derY.Value,
					new ElGamalParameters(para.P, para.G));
			}
			else if (algOid.Equals(X9ObjectIdentifiers.IdDsa)
				|| algOid.Equals(OiwObjectIdentifiers.DsaWithSha1))
			{
				DerInteger derY = (DerInteger) keyInfo.GetPublicKey();
				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 DsaPublicKeyParameters(derY.Value, parameters);
			}
			else if (algOid.Equals(X9ObjectIdentifiers.IdECPublicKey))
			{
				X962Parameters para = new X962Parameters(
					algID.Parameters.ToAsn1Object());
				X9ECParameters ecP;

				if (para.IsNamedCurve)
				{
					// TODO ECGost3410NamedCurves support (returns ECDomainParameters though)

					DerObjectIdentifier oid = (DerObjectIdentifier)para.Parameters;
					ecP = X962NamedCurves.GetByOid(oid);

					if (ecP == null)
					{
						ecP = SecNamedCurves.GetByOid(oid);

						if (ecP == null)
						{
							ecP = NistNamedCurves.GetByOid(oid);

							if (ecP == null)
							{
								ecP = TeleTrusTNamedCurves.GetByOid(oid);
							}
						}
					}
				}
				else
				{
					ecP = new X9ECParameters((Asn1Sequence)para.Parameters);
				}

				ECDomainParameters dParams = new ECDomainParameters(
					ecP.Curve,
					ecP.G,
					ecP.N,
					ecP.H,
					ecP.GetSeed());

				DerBitString bits = keyInfo.PublicKeyData;
				byte[] data = bits.GetBytes();
				Asn1OctetString key = new DerOctetString(data);

				X9ECPoint derQ = new X9ECPoint(dParams.Curve, key);

				return new ECPublicKeyParameters(derQ.Point, dParams);
			}
			else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x2001))
			{
				Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
					(Asn1Sequence) algID.Parameters);

				Asn1OctetString key;
				try
				{
					key = (Asn1OctetString) keyInfo.GetPublicKey();
				}
				catch (IOException)
				{
					throw new ArgumentException("invalid info structure in GOST3410 public key");
				}

				byte[] keyEnc = key.GetOctets();
				byte[] x = new byte[32];
				byte[] y = new byte[32];

				for (int i = 0; i != y.Length; i++)
				{
					x[i] = keyEnc[32 - 1 - i];
				}

				for (int i = 0; i != x.Length; i++)
				{
					y[i] = keyEnc[64 - 1 - i];
				}

				ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet);

				if (ecP == null)
					return null;

				ECPoint q = ecP.Curve.CreatePoint(new BigInteger(1, x), new BigInteger(1, y), false);

				return new ECPublicKeyParameters(q, gostParams.PublicKeyParamSet);
			}
			else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x94))
			{
				Gost3410PublicKeyAlgParameters algParams = new Gost3410PublicKeyAlgParameters(
					(Asn1Sequence) algID.Parameters);

				DerOctetString derY;
				try
				{
					derY = (DerOctetString) keyInfo.GetPublicKey();
				}
				catch (IOException)
				{
					throw new ArgumentException("invalid info structure in GOST3410 public key");
				}

				byte[] keyEnc = derY.GetOctets();
				byte[] keyBytes = new byte[keyEnc.Length];

				for (int i = 0; i != keyEnc.Length; i++)
				{
					keyBytes[i] = keyEnc[keyEnc.Length - 1 - i]; // was little endian
				}

				BigInteger y = new BigInteger(1, keyBytes);

				return new Gost3410PublicKeyParameters(y, algParams.PublicKeyParamSet);
			}
            else
            {
                throw new SecurityUtilityException("algorithm identifier in key not recognised: " + algOid);
            }
        }
        public static AsymmetricKeyParameter CreateKey(
            PrivateKeyInfo keyInfo)
        {
            AlgorithmIdentifier algID = keyInfo.PrivateKeyAlgorithm;
            DerObjectIdentifier algOid = algID.ObjectID;

            // 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 = new ECPrivateKeyStructure(
                    Asn1Sequence.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()));

                Asn1Object privKey = keyInfo.ParsePrivateKey();
                ECPrivateKeyStructure ec;

                if (privKey is DerInteger)
                {
                    // TODO Do we need to pass any parameters here?
                    ec = new ECPrivateKeyStructure(((DerInteger)privKey).Value);
                }
                else
                {
                    ec = ECPrivateKeyStructure.GetInstance(privKey);
                }

                ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet);

                if (ecP == null)
                    throw new ArgumentException("Unrecognized curve OID for GostR3410x2001 private key");

                return new ECPrivateKeyParameters("ECGOST3410", ec.GetKey(), gostParams.PublicKeyParamSet);
            }
            else if (algOid.Equals(CryptoProObjectIdentifiers.GostR3410x94))
            {
                Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
                    Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));

                DerOctetString derX = (DerOctetString)keyInfo.ParsePrivateKey();
                BigInteger x = new BigInteger(1, Arrays.Reverse(derX.GetOctets()));

                return new Gost3410PrivateKeyParameters(x, gostParams.PublicKeyParamSet);
            }
            else
            {
                throw new SecurityUtilityException("algorithm identifier in key not recognised");
            }
        }
        public static AsymmetricKeyParameter CreateKey(
			SubjectPublicKeyInfo keyInfo)
        {
            AlgorithmIdentifier algID = keyInfo.AlgorithmID;

            if (algID.ObjectID.Equals(PkcsObjectIdentifiers.RsaEncryption)
                || algID.ObjectID.Equals(X509ObjectIdentifiers.IdEARsa))
            {
                RsaPublicKeyStructure pubKey = RsaPublicKeyStructure.GetInstance(keyInfo.GetPublicKey());

                return new RsaKeyParameters(false, pubKey.Modulus, pubKey.PublicExponent);
            }
            else if (algID.ObjectID.Equals(PkcsObjectIdentifiers.DhKeyAgreement)
                || algID.ObjectID.Equals(X9ObjectIdentifiers.DHPublicNumber))
            {
                DHParameter para = new DHParameter((Asn1Sequence)keyInfo.AlgorithmID.Parameters);
                DerInteger derY = (DerInteger)keyInfo.GetPublicKey();

                return new DHPublicKeyParameters(derY.Value, new DHParameters(para.P, para.G));
            }
            else if (algID.ObjectID.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
            {
                ElGamalParameter para = new ElGamalParameter((Asn1Sequence)keyInfo.AlgorithmID.Parameters);
                DerInteger derY = (DerInteger)keyInfo.GetPublicKey();

                return new ElGamalPublicKeyParameters(derY.Value, new ElGamalParameters(para.P, para.G));
            }
            else if (algID.ObjectID.Equals(X9ObjectIdentifiers.IdDsa)
                || algID.ObjectID.Equals(OiwObjectIdentifiers.DsaWithSha1))
            {
                DsaParameter para = DsaParameter.GetInstance(keyInfo.AlgorithmID.Parameters);
                DerInteger derY = (DerInteger)keyInfo.GetPublicKey();

                return new DsaPublicKeyParameters(derY.Value, new DsaParameters(para.P, para.Q, para.G));
            }
            else if (algID.ObjectID.Equals(X9ObjectIdentifiers.IdECPublicKey))
            {
                X962Parameters para = new X962Parameters((Asn1Object)keyInfo.AlgorithmID.Parameters);
                ECDomainParameters dParams = null;

                if (para.IsNamedCurve)
                {
                    DerObjectIdentifier oid = (DerObjectIdentifier)para.Parameters;
                    X9ECParameters ecP = X962NamedCurves.GetByOid(oid);

                    if (ecP == null)
                    {
                        ecP = SecNamedCurves.GetByOid(oid);

                        if (ecP == null)
                        {
                            ecP = NistNamedCurves.GetByOid(oid);
                        }
                    }

                    dParams = new ECDomainParameters(
                        ecP.Curve,
                        ecP.G,
                        ecP.N,
                        ecP.H,
                        ecP.GetSeed());
                }
                else
                {
                    X9ECParameters ecP = new X9ECParameters((Asn1Sequence)para.Parameters.ToAsn1Object());

                    dParams = new ECDomainParameters(
                        ecP.Curve,
                        ecP.G,
                        ecP.N,
                        ecP.H,
                        ecP.GetSeed());
                }

                DerBitString bits = keyInfo.PublicKeyData;
                byte[] data = bits.GetBytes();
                Asn1OctetString key = new DerOctetString(data);

                X9ECPoint derQ = new X9ECPoint(dParams.Curve, key);

                return new ECPublicKeyParameters(derQ.Point, dParams);
            }
            else if (algID.ObjectID.Equals(CryptoProObjectIdentifiers.GostR3410x2001))
            {
                Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
                    (Asn1Sequence) algID.Parameters);

                Asn1OctetString key;
                try
                {
                    key = (Asn1OctetString) keyInfo.GetPublicKey();
                }
                catch (IOException)
                {
                    throw new ArgumentException("invalid info structure in GOST3410 public key");
                }

                byte[] keyEnc = key.GetOctets();
                byte[] x = new byte[32];
                byte[] y = new byte[32];

                for (int i = 0; i != y.Length; i++)
                {
                    x[i] = keyEnc[32 - 1 - i];
                }

                for (int i = 0; i != x.Length; i++)
                {
                    y[i] = keyEnc[64 - 1 - i];
                }

                ECDomainParameters ecP = ECGost3410NamedCurves.GetByOid(gostParams.PublicKeyParamSet);

                if (ecP == null)
                    return null;

                ECCurve curve = ecP.Curve;
                ECPoint q;

                if (curve is FpCurve)
                {
                    FpCurve curveFp = (FpCurve) curve;
                    q = new FpPoint(
                        curveFp,
                        new FpFieldElement(curveFp.Q, new BigInteger(1, x)),
                        new FpFieldElement(curveFp.Q, new BigInteger(1, y)));
                }
                else
                {
                    F2mCurve curveF2m = (F2mCurve) curve;
                    q = new F2mPoint(
                        curveF2m,
                        new F2mFieldElement(curveF2m.M, curveF2m.K1, curveF2m.K2, curveF2m.K3, new BigInteger(1, x)),
                        new F2mFieldElement(curveF2m.M, curveF2m.K1, curveF2m.K2, curveF2m.K3, new BigInteger(1, y)),
                        false);
                }

                return new ECPublicKeyParameters(q, gostParams.PublicKeyParamSet);
            }
            else if (algID.ObjectID.Equals(CryptoProObjectIdentifiers.GostR3410x94))
            {
                Gost3410PublicKeyAlgParameters algParams = new Gost3410PublicKeyAlgParameters(
                    (Asn1Sequence) algID.Parameters);

                DerOctetString derY;
                try
                {
                    derY = (DerOctetString) keyInfo.GetPublicKey();
                }
                catch (IOException)
                {
                    throw new ArgumentException("invalid info structure in GOST3410 public key");
                }

                byte[] keyEnc = derY.GetOctets();
                byte[] keyBytes = new byte[keyEnc.Length];

                for (int i = 0; i != keyEnc.Length; i++)
                {
                    keyBytes[i] = keyEnc[keyEnc.Length - 1 - i]; // was little endian
                }

                BigInteger y = new BigInteger(1, keyBytes);

                return new Gost3410PublicKeyParameters(y, algParams.PublicKeyParamSet);
            }
            else
            {
                throw new SecurityUtilityException("algorithm identifier in key not recognised: " + algID.ObjectID);
            }
        }
		private void doTestRandom(
			int size)
		{
//			AlgorithmParameterGenerator a = AlgorithmParameterGenerator.getInstance("ElGamal");
//			a.init(size, new SecureRandom());
			ElGamalParametersGenerator a = new ElGamalParametersGenerator();
			a.Init(size, 20, new SecureRandom());

//			AlgorithmParameters parameters = a.generateParameters();
			ElGamalParameters p = a.GenerateParameters();

//			byte[] encodeParams = parameters.GetEncoded();
			byte[] encodeParams = new ElGamalParameter(p.P, p.G).GetDerEncoded(); 

//			AlgorithmParameters a2 = AlgorithmParameters.getInstance("ElGamal");
//			a2.init(encodeParams);
			ElGamalParameter elP = new ElGamalParameter((Asn1Sequence) Asn1Object.FromByteArray(encodeParams));
			ElGamalParameters p2 = new ElGamalParameters(elP.P, elP.G);

			// a and a2 should be equivalent!
//			byte[] encodeParams_2 = a2.GetEncoded();
			byte[] encodeParams_2 = new ElGamalParameter(p2.P, p2.G).GetDerEncoded(); 

			if (!AreEqual(encodeParams, encodeParams_2))
			{
				Fail(this.Name + ": encode/decode parameters failed");
			}

//			DHParameters elP = (DHParameters)parameters.getParameterSpec(typeof(DHParameters));

			doTestGP(size, 0, elP.G, elP.P);
		}