/** Creates a new PopoSigningKeyInput using password-based MAC. */
 public PopoSigningKeyInput(
     PKMacValue pkmac,
     SubjectPublicKeyInfo spki)
 {
     this.publicKeyMac = pkmac;
     this.publicKey = spki;
 }
		public PublicKeyAndChallenge(
			Asn1Sequence seq)
		{
			pkacSeq = seq;
			spki = SubjectPublicKeyInfo.GetInstance(seq[0]);
			challenge = DerIA5String.GetInstance(seq[1]);
		}
 /** Creates a new PopoSigningKeyInput with sender name as authInfo. */
 public PopoSigningKeyInput(
     GeneralName sender,
     SubjectPublicKeyInfo spki)
 {
     this.sender = sender;
     this.publicKey = spki;
 }
		public CertificationRequestInfo(
            X509Name				subject,
            SubjectPublicKeyInfo	pkInfo,
            Asn1Set					attributes)
        {
            this.subject = subject;
            this.subjectPKInfo = pkInfo;
            this.attributes = attributes;

			if (subject == null || version == null || subjectPKInfo == null)
            {
                throw new ArgumentException(
					"Not all mandatory fields set in CertificationRequestInfo generator.");
            }
        }
		public X509CertStoreSelector(
			X509CertStoreSelector o)
		{
			this.authorityKeyIdentifier = o.AuthorityKeyIdentifier;
			this.basicConstraints = o.BasicConstraints;
			this.certificate = o.Certificate;
			this.certificateValid = o.CertificateValid;
			this.extendedKeyUsage = o.ExtendedKeyUsage;
			this.issuer = o.Issuer;
			this.keyUsage = o.KeyUsage;
			this.policy = o.Policy;
			this.privateKeyValid = o.PrivateKeyValid;
			this.serialNumber = o.SerialNumber;
			this.subject = o.Subject;
			this.subjectKeyIdentifier = o.SubjectKeyIdentifier;
			this.subjectPublicKey = o.SubjectPublicKey;
			this.subjectPublicKeyAlgID = o.SubjectPublicKeyAlgID;
		}
        private CertTemplate(Asn1Sequence seq)
        {
            this.seq = seq;

            foreach (Asn1TaggedObject tObj in seq)
            {
                switch (tObj.TagNo)
                {
                case 0:
                    version = DerInteger.GetInstance(tObj, false);
                    break;
                case 1:
                    serialNumber = DerInteger.GetInstance(tObj, false);
                    break;
                case 2:
                    signingAlg = AlgorithmIdentifier.GetInstance(tObj, false);
                    break;
                case 3:
                    issuer = X509Name.GetInstance(tObj, true); // CHOICE
                    break;
                case 4:
                    validity = OptionalValidity.GetInstance(Asn1Sequence.GetInstance(tObj, false));
                    break;
                case 5:
                    subject = X509Name.GetInstance(tObj, true); // CHOICE
                    break;
                case 6:
                    publicKey = SubjectPublicKeyInfo.GetInstance(tObj, false);
                    break;
                case 7:
                    issuerUID = DerBitString.GetInstance(tObj, false);
                    break;
                case 8:
                    subjectUID = DerBitString.GetInstance(tObj, false);
                    break;
                case 9:
                    extensions = X509Extensions.GetInstance(tObj, false);
                    break;
                default:
                    throw new ArgumentException("unknown tag: " + tObj.TagNo, "seq");
                }
            }
        }
        private PopoSigningKeyInput(Asn1Sequence seq)
        {
            Asn1Encodable authInfo = (Asn1Encodable)seq[0];

            if (authInfo is Asn1TaggedObject)
            {
                Asn1TaggedObject tagObj = (Asn1TaggedObject)authInfo;
                if (tagObj.TagNo != 0)
                {
                    throw new ArgumentException("Unknown authInfo tag: " + tagObj.TagNo, "seq");
                }
                sender = GeneralName.GetInstance(tagObj.GetObject());
            }
            else
            {
                publicKeyMac = PKMacValue.GetInstance(authInfo);
            }

            publicKey = SubjectPublicKeyInfo.GetInstance(seq[1]);
        }
		private CertificationRequestInfo(
            Asn1Sequence seq)
        {
            version = (DerInteger) seq[0];

			subject = X509Name.GetInstance(seq[1]);
            subjectPKInfo = SubjectPublicKeyInfo.GetInstance(seq[2]);

			//
            // some CertificationRequestInfo objects seem to treat this field
            // as optional.
            //
            if (seq.Count > 3)
            {
                DerTaggedObject tagobj = (DerTaggedObject) seq[3];
                attributes = Asn1Set.GetInstance(tagobj, false);
            }

			if (subject == null || version == null || subjectPKInfo == null)
            {
                throw new ArgumentException(
					"Not all mandatory fields set in CertificationRequestInfo generator.");
            }
        }
		/**
		 * Return a RFC 3280 type 2 key identifier. As in:
		 * <pre>
		 * (2) The keyIdentifier is composed of a four bit type field with
		 * the value 0100 followed by the least significant 60 bits of the
		 * SHA-1 hash of the value of the BIT STRING subjectPublicKey.
		 * </pre>
		 * @param keyInfo the key info object containing the subjectPublicKey field.
		 * @return the key identifier.
		 */
		public static SubjectKeyIdentifier CreateTruncatedSha1KeyIdentifier(
			SubjectPublicKeyInfo keyInfo)
		{
			byte[] dig = GetDigest(keyInfo);
			byte[] id = new byte[8];

			Array.Copy(dig, dig.Length - 8, id, 0, id.Length);

			id[0] &= 0x0f;
			id[0] |= 0x40;

			return new SubjectKeyIdentifier(id);
		}
		public void SetSubjectPublicKeyInfo(
            SubjectPublicKeyInfo pubKeyInfo)
        {
            this.subjectPublicKeyInfo = pubKeyInfo;
        }
		private AsymmetricKeyParameter GetPublicKeyFromOriginatorPublicKey(
			AsymmetricKeyParameter	receiverPrivateKey,
			OriginatorPublicKey		originatorPublicKey)
		{
			PrivateKeyInfo privInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(receiverPrivateKey);
			SubjectPublicKeyInfo pubInfo = new SubjectPublicKeyInfo(
				privInfo.AlgorithmID,
				originatorPublicKey.PublicKey.GetBytes());
			return PublicKeyFactory.CreateKey(pubInfo);
		}
		/**
		 * Calculates the keyIdentifier using a SHA1 hash over the BIT STRING
		 * from SubjectPublicKeyInfo as defined in RFC3280.
		 *
		 * @param spki the subject public key info.
		 */
		public SubjectKeyIdentifier(
			SubjectPublicKeyInfo spki)
		{
			this.keyIdentifier = GetDigest(spki);
		}
		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 ecP;

				if (para.IsNamedCurve)
				{
					ecP = ECKeyPairGenerator.FindECCurveByOid((DerObjectIdentifier)para.Parameters);
				}
				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("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 virtual CertTemplateBuilder SetPublicKey(SubjectPublicKeyInfo spki)
 {
     publicKey = spki;
     return this;
 }
		internal TbsCertificateStructure(
			Asn1Sequence seq)
		{
			int seqStart = 0;

			this.seq = seq;

			//
			// some certficates don't include a version number - we assume v1
			//
			if (seq[0] is DerTaggedObject)
			{
				version = DerInteger.GetInstance((Asn1TaggedObject)seq[0], true);
			}
			else
			{
				seqStart = -1;          // field 0 is missing!
				version = new DerInteger(0);
			}

			serialNumber = DerInteger.GetInstance(seq[seqStart + 1]);

			signature = AlgorithmIdentifier.GetInstance(seq[seqStart + 2]);
			issuer = X509Name.GetInstance(seq[seqStart + 3]);

			//
			// before and after dates
			//
			Asn1Sequence  dates = (Asn1Sequence)seq[seqStart + 4];

			startDate = Time.GetInstance(dates[0]);
			endDate = Time.GetInstance(dates[1]);

			subject = X509Name.GetInstance(seq[seqStart + 5]);

			//
			// public key info.
			//
			subjectPublicKeyInfo = SubjectPublicKeyInfo.GetInstance(seq[seqStart + 6]);

			for (int extras = seq.Count - (seqStart + 6) - 1; extras > 0; extras--)
			{
				DerTaggedObject extra = (DerTaggedObject) seq[seqStart + 6 + extras];

				switch (extra.TagNo)
				{
					case 1:
						issuerUniqueID = DerBitString.GetInstance(extra, false);
						break;
					case 2:
						subjectUniqueID = DerBitString.GetInstance(extra, false);
						break;
					case 3:
						extensions = X509Extensions.GetInstance(extra);
						break;
				}
			}
		}
		private static byte[] GetDigest(
			SubjectPublicKeyInfo spki)
		{
            IDigest digest = new Sha1Digest();
            byte[] resBuf = new byte[digest.GetDigestSize()];

			byte[] bytes = spki.PublicKeyData.GetBytes();
            digest.BlockUpdate(bytes, 0, bytes.Length);
            digest.DoFinal(resBuf, 0);
            return resBuf;
		}
        /**
         * create an AuthorityKeyIdentifier with the GeneralNames tag and
         * the serial number provided as well.
         */
        public AuthorityKeyIdentifier(
            SubjectPublicKeyInfo	spki,
            GeneralNames			name,
            BigInteger				serialNumber)
        {
            IDigest digest = new Sha1Digest();
            byte[] resBuf = new byte[digest.GetDigestSize()];

			byte[] bytes = spki.PublicKeyData.GetBytes();
            digest.BlockUpdate(bytes, 0, bytes.Length);
            digest.DoFinal(resBuf, 0);

			this.keyidentifier = new DerOctetString(resBuf);
            this.certissuer = name;
            this.certserno = new DerInteger(serialNumber);
        }
		/**
		 * Return a RFC 3280 type 1 key identifier. As in:
		 * <pre>
		 * (1) The keyIdentifier is composed of the 160-bit SHA-1 hash of the
		 * value of the BIT STRING subjectPublicKey (excluding the tag,
		 * length, and number of unused bits).
		 * </pre>
		 * @param keyInfo the key info object containing the subjectPublicKey field.
		 * @return the key identifier.
		 */
		public static SubjectKeyIdentifier CreateSha1KeyIdentifier(
			SubjectPublicKeyInfo keyInfo)
		{
			return new SubjectKeyIdentifier(keyInfo);
		}
Beispiel #19
0
 /**
  * Return a RFC 3280 type 1 key identifier. As in:
  * <pre>
  * (1) The keyIdentifier is composed of the 160-bit SHA-1 hash of the
  * value of the BIT STRING subjectPublicKey (excluding the tag,
  * length, and number of unused bits).
  * </pre>
  * @param keyInfo the key info object containing the subjectPublicKey field.
  * @return the key identifier.
  */
 public static SubjectKeyIdentifier CreateSha1KeyIdentifier(
     SubjectPublicKeyInfo keyInfo)
 {
     return(new SubjectKeyIdentifier(keyInfo));
 }
Beispiel #20
0
 /**
  * Calculates the keyIdentifier using a SHA1 hash over the BIT STRING
  * from SubjectPublicKeyInfo as defined in RFC3280.
  *
  * @param spki the subject public key info.
  */
 public SubjectKeyIdentifier(
     SubjectPublicKeyInfo spki)
 {
     this.keyIdentifier = GetDigest(spki);
 }
		/**
         *
         * Calulates the keyidentifier using a SHA1 hash over the BIT STRING
         * from SubjectPublicKeyInfo as defined in RFC2459.
         *
         * Example of making a AuthorityKeyIdentifier:
         * <pre>
	     *   SubjectPublicKeyInfo apki = new SubjectPublicKeyInfo((ASN1Sequence)new ASN1InputStream(
		 *       publicKey.getEncoded()).readObject());
         *   AuthorityKeyIdentifier aki = new AuthorityKeyIdentifier(apki);
         * </pre>
         *
         **/
        public AuthorityKeyIdentifier(
            SubjectPublicKeyInfo spki)
        {
            IDigest digest = new Sha1Digest();
            byte[] resBuf = new byte[digest.GetDigestSize()];

			byte[] bytes = spki.PublicKeyData.GetBytes();
            digest.BlockUpdate(bytes, 0, bytes.Length);
            digest.DoFinal(resBuf, 0);
            this.keyidentifier = new DerOctetString(resBuf);
        }
Beispiel #22
0
		/**
		* Read a Key Pair
		*/
		private object ReadPrivateKey(PemObject pemObject)
		{
			//
			// extract the key
			//
			Debug.Assert(pemObject.Type.EndsWith("PRIVATE KEY"));

			string type = pemObject.Type.Substring(0, pemObject.Type.Length - "PRIVATE KEY".Length).Trim();
			byte[] keyBytes = pemObject.Content;

			IDictionary fields = Platform.CreateHashtable();
			foreach (PemHeader header in pemObject.Headers)
			{
				fields[header.Name] = header.Value;
			}

			string procType = (string) fields["Proc-Type"];

			if (procType == "4,ENCRYPTED")
			{
				if (pFinder == null)
					throw new PasswordException("No password finder specified, but a password is required");

				char[] password = pFinder.GetPassword();

				if (password == null)
					throw new PasswordException("Password is null, but a password is required");

				string dekInfo = (string) fields["DEK-Info"];
				string[] tknz = dekInfo.Split(',');

				string dekAlgName = tknz[0].Trim();
				byte[] iv = Hex.Decode(tknz[1].Trim());

				keyBytes = PemUtilities.Crypt(false, keyBytes, password, dekAlgName, iv);
			}

			try
			{
				AsymmetricKeyParameter pubSpec, privSpec;
				Asn1Sequence seq = (Asn1Sequence) Asn1Object.FromByteArray(keyBytes);

				switch (type)
				{
					case "RSA":
					{
						if (seq.Count != 9)
							throw new PemException("malformed sequence in RSA private key");

						RsaPrivateKeyStructure rsa = new RsaPrivateKeyStructure(seq);

						pubSpec = new RsaKeyParameters(false, rsa.Modulus, rsa.PublicExponent);
						privSpec = new RsaPrivateCrtKeyParameters(
							rsa.Modulus, rsa.PublicExponent, rsa.PrivateExponent,
							rsa.Prime1, rsa.Prime2, rsa.Exponent1, rsa.Exponent2,
							rsa.Coefficient);

						break;
					}

					case "DSA":
					{
						if (seq.Count != 6)
							throw new PemException("malformed sequence in DSA private key");

						// TODO Create an ASN1 object somewhere for this?
						//DerInteger v = (DerInteger)seq[0];
						DerInteger p = (DerInteger)seq[1];
						DerInteger q = (DerInteger)seq[2];
						DerInteger g = (DerInteger)seq[3];
						DerInteger y = (DerInteger)seq[4];
						DerInteger x = (DerInteger)seq[5];

						DsaParameters parameters = new DsaParameters(p.Value, q.Value, g.Value);

						privSpec = new DsaPrivateKeyParameters(x.Value, parameters);
						pubSpec = new DsaPublicKeyParameters(y.Value, parameters);

						break;
					}

					case "EC":
					{
						ECPrivateKeyStructure pKey = new ECPrivateKeyStructure(seq);
						AlgorithmIdentifier algId = new AlgorithmIdentifier(
							X9ObjectIdentifiers.IdECPublicKey, pKey.GetParameters());

						PrivateKeyInfo privInfo = new PrivateKeyInfo(algId, pKey.ToAsn1Object());

						// TODO Are the keys returned here ECDSA, as Java version forces?
						privSpec = PrivateKeyFactory.CreateKey(privInfo);

						DerBitString pubKey = pKey.GetPublicKey();
						if (pubKey != null)
						{
							SubjectPublicKeyInfo pubInfo = new SubjectPublicKeyInfo(algId, pubKey.GetBytes());

							// TODO Are the keys returned here ECDSA, as Java version forces?
							pubSpec = PublicKeyFactory.CreateKey(pubInfo);
						}
						else
						{
							pubSpec = ECKeyPairGenerator.GetCorrespondingPublicKey(
								(ECPrivateKeyParameters)privSpec);
						}

						break;
					}

					case "ENCRYPTED":
					{
						char[] password = pFinder.GetPassword();

						if (password == null)
							throw new PasswordException("Password is null, but a password is required");

						return PrivateKeyFactory.DecryptKey(password, EncryptedPrivateKeyInfo.GetInstance(seq));
					}

					case "":
					{
						return PrivateKeyFactory.CreateKey(PrivateKeyInfo.GetInstance(seq));
					}

					default:
						throw new ArgumentException("Unknown key type: " + type, "type");
				}

				return new AsymmetricCipherKeyPair(pubSpec, privSpec);
			}
			catch (IOException e)
			{
				throw e;
			}
			catch (Exception e)
			{
				throw new PemException(
					"problem creating " + type + " private key: " + e.ToString());
			}
		}
Beispiel #23
0
 public void SetSubjectPublicKeyInfo(
     SubjectPublicKeyInfo pubKeyInfo)
 {
     this.subjectPublicKeyInfo = pubKeyInfo;
 }
		/// <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 == null)
				throw new ArgumentNullException("key");
            if (key.IsPrivate)
                throw new ArgumentException("Private key passed - public key expected.", "key");

			if (key is ElGamalPublicKeyParameters)
            {
				ElGamalPublicKeyParameters _key = (ElGamalPublicKeyParameters)key;
				ElGamalParameters kp = _key.Parameters;

				SubjectPublicKeyInfo info = new SubjectPublicKeyInfo(
					new AlgorithmIdentifier(
						OiwObjectIdentifiers.ElGamalAlgorithm,
						new ElGamalParameter(kp.P, kp.G).ToAsn1Object()),
						new DerInteger(_key.Y));

				return info;
            }

			if (key is DsaPublicKeyParameters)
            {
                DsaPublicKeyParameters _key = (DsaPublicKeyParameters) key;
				DsaParameters kp = _key.Parameters;
				Asn1Encodable ae = kp == null
					?	null
					:	new DsaParameter(kp.P, kp.Q, kp.G).ToAsn1Object();

				return new SubjectPublicKeyInfo(
                    new AlgorithmIdentifier(X9ObjectIdentifiers.IdDsa, ae),
					new DerInteger(_key.Y));
            }

			if (key is DHPublicKeyParameters)
            {
                DHPublicKeyParameters _key = (DHPublicKeyParameters) key;
				DHParameters kp = _key.Parameters;

				SubjectPublicKeyInfo info = new SubjectPublicKeyInfo(
                    new AlgorithmIdentifier(
						_key.AlgorithmOid,
						new DHParameter(kp.P, kp.G, kp.L).ToAsn1Object()),
						new DerInteger(_key.Y));

				return info;
            } // End of DH

            if (key is RsaKeyParameters)
            {
                RsaKeyParameters _key = (RsaKeyParameters) key;

				SubjectPublicKeyInfo info = new SubjectPublicKeyInfo(
					new AlgorithmIdentifier(PkcsObjectIdentifiers.RsaEncryption, DerNull.Instance),
					new RsaPublicKeyStructure(_key.Modulus, _key.Exponent).ToAsn1Object());

				return info;
            } // End of RSA.

			if (key is ECPublicKeyParameters)
            {
                ECPublicKeyParameters _key = (ECPublicKeyParameters) key;

				if (_key.AlgorithmName == "ECGOST3410")
				{
					if (_key.PublicKeyParamSet == null)
						throw Platform.CreateNotImplementedException("Not a CryptoPro parameter set");

					ECPoint q = _key.Q;
					BigInteger bX = q.X.ToBigInteger();
					BigInteger bY = q.Y.ToBigInteger();

					byte[] encKey = new byte[64];
					ExtractBytes(encKey, 0, bX);
					ExtractBytes(encKey, 32, bY);

					Gost3410PublicKeyAlgParameters gostParams = new Gost3410PublicKeyAlgParameters(
						_key.PublicKeyParamSet, CryptoProObjectIdentifiers.GostR3411x94CryptoProParamSet);

					AlgorithmIdentifier algID = new AlgorithmIdentifier(
						CryptoProObjectIdentifiers.GostR3410x2001,
						gostParams.ToAsn1Object());

					return new SubjectPublicKeyInfo(algID, new DerOctetString(encKey));
				}
				else
				{
					X962Parameters x962;
					if (_key.PublicKeyParamSet == null)
					{
						ECDomainParameters kp = _key.Parameters;
						X9ECParameters ecP = new X9ECParameters(kp.Curve, kp.G, kp.N, kp.H, kp.GetSeed());

						x962 = new X962Parameters(ecP);
					}
					else
					{
						x962 = new X962Parameters(_key.PublicKeyParamSet);
					}

					Asn1OctetString p = (Asn1OctetString)(new X9ECPoint(_key.Q).ToAsn1Object());

					AlgorithmIdentifier algID = new AlgorithmIdentifier(
						X9ObjectIdentifiers.IdECPublicKey, x962.ToAsn1Object());

					return new SubjectPublicKeyInfo(algID, p.GetOctets());
				}
			} // End of EC

			if (key is Gost3410PublicKeyParameters)
			{
				Gost3410PublicKeyParameters _key = (Gost3410PublicKeyParameters) key;

				if (_key.PublicKeyParamSet == null)
					throw Platform.CreateNotImplementedException("Not a CryptoPro parameter set");

				byte[] keyEnc = _key.Y.ToByteArrayUnsigned();
				byte[] keyBytes = new byte[keyEnc.Length];

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

				Gost3410PublicKeyAlgParameters algParams = new Gost3410PublicKeyAlgParameters(
					_key.PublicKeyParamSet, CryptoProObjectIdentifiers.GostR3411x94CryptoProParamSet);

				AlgorithmIdentifier algID = new AlgorithmIdentifier(
					CryptoProObjectIdentifiers.GostR3410x94,
					algParams.ToAsn1Object());

				return new SubjectPublicKeyInfo(algID, new DerOctetString(keyBytes));
			}

			throw new ArgumentException("Class provided no convertible: " + key.GetType().FullName);
		}