Add protocol version DTLS 1.2.

Reuse that version instance.

Signed-off-by: Achim Kraus <achim.kraus@bosch.io>

scandium-core/src/main/java/org/eclipse/californium/scandium/DTLSConnector.java

@@ -2076,7 +2076,7 @@ private void sendHelloVerify(ClientHello clientHello, Record record, byte[] expe
 		if (expectedCookie == null) {
 			expectedCookie = cookieGenerator.generateCookie(clientHello);
 		}
-		HelloVerifyRequest msg = new HelloVerifyRequest(new ProtocolVersion(), expectedCookie, record.getPeerAddress());
+		HelloVerifyRequest msg = new HelloVerifyRequest(ProtocolVersion.VERSION_DTLS_1_2, expectedCookie, record.getPeerAddress());
 		// because we do not have a handshaker in place yet that
 		// manages message_seq numbers, we need to set it explicitly
 		// use message_seq from CLIENT_HELLO in order to allow for

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/ClientHandshaker.java

@@ -94,7 +94,7 @@ public class ClientHandshaker extends Handshaker {
 
 	// Members ////////////////////////////////////////////////////////
 
-	private ProtocolVersion maxProtocolVersion = new ProtocolVersion();
+	private ProtocolVersion maxProtocolVersion = ProtocolVersion.VERSION_DTLS_1_2;
 
 	/**
 	 * Indicates probing for this handshake.

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/ClientHello.java

@@ -69,7 +69,7 @@ public final class ClientHello extends HandshakeMessage {
 	 * The version of the DTLS protocol by which the client wishes to
 	 * communicate during this session.
 	 */
-	private ProtocolVersion clientVersion = new ProtocolVersion();
+	private ProtocolVersion clientVersion;
 
 	/** A client-generated random structure. */
 	private Random random;
@@ -307,7 +307,7 @@ public static ClientHello fromReader(DatagramReader reader, InetSocketAddress pe
 
 		int major = reader.read(VERSION_BITS);
 		int minor = reader.read(VERSION_BITS);
-		result.clientVersion = new ProtocolVersion(major, minor);
+		result.clientVersion = ProtocolVersion.valueOf(major, minor);
 
 		result.random = new Random(reader.readBytes(RANDOM_BYTES));
 

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/DTLSSession.java

@@ -1176,7 +1176,7 @@ else if (sessionIdentifier.isEmpty()) {
 			return null;
 		}
 		return new SessionTicket(
-				new ProtocolVersion(),
+				ProtocolVersion.VERSION_DTLS_1_2,
 				writeState.getCipherSuite(),
 				writeState.getCompressionMethod(),
 				masterSecret,

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/HelloVerifyRequest.java

@@ -76,7 +76,7 @@ public static HandshakeMessage fromReader(DatagramReader reader, InetSocketAddre
 
 		int major = reader.read(VERSION_BITS);
 		int minor = reader.read(VERSION_BITS);
-		ProtocolVersion version = new ProtocolVersion(major, minor);
+		ProtocolVersion version = ProtocolVersion.valueOf(major, minor);
 
 		int cookieLength = reader.read(COOKIE_LENGTH_BITS);
 		byte[] cookie = reader.readBytes(cookieLength);

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/ProtocolVersion.java

@@ -20,38 +20,65 @@
 /**
  * Represents the DTLS protocol version.
  * 
- * Note that the major and minor version numbers are represented
- * as the 1's complement of the corresponding DTLS version numbers,
- * e.g. DTLS version 1.2 is represented as bytes {254, 253}.
+ * Note that the major and minor version numbers are represented as the 1's
+ * complement of the corresponding DTLS version numbers, e.g. DTLS version 1.2
+ * is represented as bytes {254, 253}.
  * 
- * See <a href="http://tools.ietf.org/html/rfc6347#section-4.1">
- * Datagram Transport Layer Security Version 1.2 (RFC 6347), Section 4.1</a>
- * for details.
+ * See <a href="http://tools.ietf.org/html/rfc6347#section-4.1"> Datagram
+ * Transport Layer Security Version 1.2 (RFC 6347), Section 4.1</a> for details.
  */
 public class ProtocolVersion implements Comparable<ProtocolVersion> {
 
+	/**
+	 * Major version for DTLS 1.2.
+	 * 
+	 * @since 2.4
+	 */
+	public static final int MAJOR_1_2 = 254;
+
+	/**
+	 * Minor version for DTLS 1.2.
+	 * 
+	 * @since 2.4
+	 */
+	public static final int MINOR_1_2 = 253;
+
+	/**
+	 * Protocol version DTLS 1.2
+	 * 
+	 * @since 2.4
+	 */
+	public static final ProtocolVersion VERSION_DTLS_1_2 = new ProtocolVersion(MAJOR_1_2, MINOR_1_2);
+
 	/** The minor. */
-	private int minor;
+	private final int minor;
 
 	/** The major. */
-	private int major;
+	private final int major;
 
 	/**
 	 * Creates an instance representing DTLS version 1.2.
 	 * 
 	 * The version is represented as {254, 253} (1's complement of {1, 2}).
+	 * 
+	 * @deprecated use {@link #VERSION_DTLS_1_2} or {@link #valueOf(int, int)}
+	 *             instead.
 	 */
+	@Deprecated
 	public ProtocolVersion() {
-		this.major = 254;
-		this.minor = 253;
+		this.major = MAJOR_1_2;
+		this.minor = MINOR_1_2;
 	}
 
 	/**
 	 * Instantiates a new protocol version.
 	 *
 	 * @param major the major
 	 * @param minor the minor
+	 * @deprecated intended to became private. Use {@link #valueOf(int, int)}
+	 *             instead.
 	 */
+	@Deprecated
 	public ProtocolVersion(int major, int minor) {
 		this.minor = minor;
 		this.major = major;
@@ -69,21 +96,27 @@ public int getMajor() {
 	 * Compares this protocol version to another one.
 	 * 
 	 * Note that the comparison is done based on the <em>semantic</em> version,
-	 * i.e. DTLS protocol version 1.0 (represented as major 254, minor 255) is considered
-	 * <em>lower</em> than 1.2 (represented as major 254, minor 253) whereas the
-	 * byte values representing version 1.0 are actually larger.
+	 * i.e. DTLS protocol version 1.0 (represented as major 254, minor 255) is
+	 * considered <em>lower</em> than 1.2 (represented as major 254, minor 253)
+	 * whereas the byte values representing version 1.0 are actually larger.
 	 * 
 	 * @param o the protocol version to compare to
-	 * @return <em>0</em> if this version is exactly the same as the other version,
-	 *         <em>-1</em> if this version is lower than the other version or
-	 *         <em>1</em> if this version is higher than the other version
+	 * @return <em>0</em> if this version is exactly the same as the other
+	 *         version, <em>-1</em> if this version is lower than the other
+	 *         version or <em>1</em> if this version is higher than the other
+	 *         version
 	 */
 	@Override
 	public int compareTo(ProtocolVersion o) {
+
+		if (this == o) {
+			return 0;
+		}
+
 		/*
 		 * Example, version 1.0 (254,255) is smaller than version 1.2 (254,253)
 		 */
-		
+
 		if (major == o.getMajor()) {
 			if (minor < o.getMinor()) {
 				return 1;
@@ -121,4 +154,24 @@ public boolean equals(Object obj) {
 			return major == other.major && minor == other.minor;
 		}
 	}
+
+	@Override
+	public String toString() {
+		return Integer.toString(255 - major) + "." + Integer.toString(255 - minor);
+	}
+
+	/**
+	 * Get protocol version value of the provided versions.
+	 * 
+	 * @param major major version
+	 * @param minor minor version
+	 * @return protocol version
+	 */
+	public static ProtocolVersion valueOf(int major, int minor) {
+		if (major == MAJOR_1_2 && minor == MINOR_1_2) {
+			return VERSION_DTLS_1_2;
+		} else {
+			return new ProtocolVersion(major, minor);
+		}
+	}
 }

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/Record.java

@@ -204,7 +204,7 @@ public class Record {
 	 */
 	public Record(ContentType type, int epoch, long sequenceNumber, DTLSMessage fragment, DTLSSession session,
 			boolean cid, int pad) throws GeneralSecurityException {
-		this(new ProtocolVersion(), epoch, sequenceNumber, 0, session != null ? session.getPeer() : null, false);
+		this(ProtocolVersion.VERSION_DTLS_1_2, epoch, sequenceNumber, 0, session != null ? session.getPeer() : null, false);
 		if (fragment == null) {
 			throw new NullPointerException("Fragment must not be null");
 		} else if (session == null) {
@@ -241,7 +241,7 @@ public Record(ContentType type, int epoch, long sequenceNumber, DTLSMessage frag
 	 *             is {@code null}.
 	 */
 	public Record(ContentType type, long sequenceNumber, DTLSMessage fragment, InetSocketAddress peerAddress) {
-		this(new ProtocolVersion(), 0, sequenceNumber, 0, peerAddress, false);
+		this(ProtocolVersion.VERSION_DTLS_1_2, 0, sequenceNumber, 0, peerAddress, false);
 		if (fragment == null) {
 			throw new NullPointerException("Fragment must not be null");
 		} else if (peerAddress == null) {
@@ -371,7 +371,7 @@ public static List<Record> fromReader(DatagramReader reader, InetSocketAddress p
 			int type = reader.read(CONTENT_TYPE_BITS);
 			int major = reader.read(VERSION_BITS);
 			int minor = reader.read(VERSION_BITS);
-			ProtocolVersion version = new ProtocolVersion(major, minor);
+			ProtocolVersion version = ProtocolVersion.valueOf(major, minor);
 
 			int epoch = reader.read(EPOCH_BITS);
 			long sequenceNumber = reader.readLong(SEQUENCE_NUMBER_BITS);

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/ResumingClientHandshaker.java

@@ -254,7 +254,7 @@ private void receivedServerFinished(Finished message) throws HandshakeException
 	@Override
 	public void startHandshake() throws HandshakeException {
 		handshakeStarted();
-		ClientHello message = new ClientHello(new ProtocolVersion(), session, supportedSignatureAlgorithms,
+		ClientHello message = new ClientHello(ProtocolVersion.VERSION_DTLS_1_2, session, supportedSignatureAlgorithms,
 				supportedClientCertificateTypes, supportedServerCertificateTypes, supportedGroups);
 
 		clientRandom = message.getRandom();

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/ServerHandshaker.java

@@ -702,9 +702,8 @@ public void startHandshake() throws HandshakeException {
 	 *             if the client's version is smaller than DTLS 1.2
 	 */
 	private ProtocolVersion negotiateProtocolVersion(ProtocolVersion clientVersion) throws HandshakeException {
-		ProtocolVersion version = new ProtocolVersion();
-		if (clientVersion.compareTo(version) >= 0) {
-			return new ProtocolVersion();
+		if (clientVersion.compareTo(ProtocolVersion.VERSION_DTLS_1_2) >= 0) {
+			return ProtocolVersion.VERSION_DTLS_1_2;
 		} else {
 			AlertMessage alert = new AlertMessage(AlertLevel.FATAL, AlertDescription.PROTOCOL_VERSION, session.getPeer());
 			throw new HandshakeException("The server only supports DTLS v1.2", alert);

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/ServerHello.java

@@ -180,7 +180,7 @@ public static HandshakeMessage fromReader(DatagramReader reader, InetSocketAddre
 
 		int major = reader.read(VERSION_BITS);
 		int minor = reader.read(VERSION_BITS);
-		ProtocolVersion version = new ProtocolVersion(major, minor);
+		ProtocolVersion version = ProtocolVersion.valueOf(major, minor);
 
 		Random random = new Random(reader.readBytes(RANDOM_BYTES));
 

scandium-core/src/main/java/org/eclipse/californium/scandium/dtls/SessionTicket.java

@@ -180,7 +180,7 @@ public static SessionTicket decode(final DatagramReader source) {
 		// protocol_version
 		int major = source.read(8);
 		int minor = source.read(8);
-		ProtocolVersion ver = new ProtocolVersion(major, minor);
+		ProtocolVersion ver = ProtocolVersion.valueOf(major, minor);
 
 		// cipher_suite
 		CipherSuite cipherSuite = CipherSuite.getTypeByCode(source.read(CipherSuite.CIPHER_SUITE_BITS));

scandium-core/src/test/java/org/eclipse/californium/scandium/DTLSConnectorTest.java

@@ -1017,7 +1017,7 @@ private ClientHello createClientHello(CipherSuite... cipherSuites) {
 		if (cipherSuites != null && cipherSuites.length > 0) {
 			list = Arrays.asList(cipherSuites);
 		}
-		ClientHello hello = new ClientHello(new ProtocolVersion(), list, clientConfig.getSupportedSignatureAlgorithms(),
+		ClientHello hello = new ClientHello(ProtocolVersion.VERSION_DTLS_1_2, list, clientConfig.getSupportedSignatureAlgorithms(),
 				clientConfig.getIdentityCertificateTypes(), clientConfig.getTrustCertificateTypes(),
 				clientConfig.getSupportedGroups(), clientEndpoint);
 		hello.addCompressionMethod(CompressionMethod.NULL);

scandium-core/src/test/java/org/eclipse/californium/scandium/dtls/ClientHelloTest.java

@@ -106,7 +106,7 @@ Collections.<CertificateType> emptyList(),
 	}
 
 	private void givenAClientHelloWithEmptyExtensions() {
-		clientHello = new ClientHello(new ProtocolVersion(), Collections.<CipherSuite> emptyList(),
+		clientHello = new ClientHello(ProtocolVersion.VERSION_DTLS_1_2, Collections.<CipherSuite> emptyList(),
 				SignatureAndHashAlgorithm.DEFAULT, null, null,
 				Collections.<SupportedGroup> emptyList(), peerAddress);
 	}
@@ -125,7 +125,7 @@ public static ClientHello createClientHello(InetSocketAddress address, List<Ciph
 			List<CertificateType> supportedClientCertTypes, List<CertificateType> supportedServerCertTypes,
 			List<SupportedGroup> supportedGroups) {
 
-		return new ClientHello(new ProtocolVersion(), supportedCipherSuites, supportedSignatureAndHashAlgorithms,
+		return new ClientHello(ProtocolVersion.VERSION_DTLS_1_2, supportedCipherSuites, supportedSignatureAndHashAlgorithms,
 				supportedClientCertTypes, supportedServerCertTypes, supportedGroups, address);
 	}
 

scandium-core/src/test/java/org/eclipse/californium/scandium/dtls/DtlsTestTools.java

@@ -47,7 +47,7 @@ public static Record getRecordForMessage(int epoch, int seqNo, DTLSMessage msg,
 
 	public static final byte[] newDTLSRecord(int typeCode, int epoch, long sequenceNo, byte[] fragment) {
 
-		ProtocolVersion protocolVer = new ProtocolVersion();
+		ProtocolVersion protocolVer = ProtocolVersion.VERSION_DTLS_1_2;
 		// the record header contains a type code, version, epoch, sequenceNo, length
 		DatagramWriter writer = new DatagramWriter();
 		writer.write(typeCode, 8);

scandium-core/src/test/java/org/eclipse/californium/scandium/dtls/HandshakerTest.java

@@ -429,7 +429,7 @@ private void assertThatCertificateValidationFailsForEmptyTrustAnchor() {
 	}
 
 	private static Record createClientHelloRecord(DTLSSession session, int epoch, long sequenceNo, int messageSeqNo) throws GeneralSecurityException {
-		ClientHello clientHello = new ClientHello(new ProtocolVersion(), session, Collections.<SignatureAndHashAlgorithm> emptyList(), null, null, SupportedGroup.getPreferredGroups());
+		ClientHello clientHello = new ClientHello(ProtocolVersion.VERSION_DTLS_1_2, session, Collections.<SignatureAndHashAlgorithm> emptyList(), null, null, SupportedGroup.getPreferredGroups());
 		clientHello.setMessageSeq(messageSeqNo);
 		return getRecordForMessage(epoch, sequenceNo, clientHello);
 	}

scandium-core/src/test/java/org/eclipse/californium/scandium/dtls/RecordTest.java

@@ -63,7 +63,7 @@ public class RecordTest {
 	@Before
 	public void setUp() throws Exception {
 
-		protocolVer = new ProtocolVersion();
+		protocolVer = ProtocolVersion.VERSION_DTLS_1_2;
 		key = new SecretKeySpec(aesKey, "AES");
 		payloadData = new byte[payloadLength];
 		for ( int i = 0; i < payloadLength; i++) {

scandium-core/src/test/java/org/eclipse/californium/scandium/dtls/ServerHelloTest.java

@@ -70,12 +70,12 @@ private void givenAServerHelloWith(CertificateType serverType, CertificateType c
 		if (clientType != null) {
 			ext.addExtension(new ClientCertificateTypeExtension(clientType));
 		}
-		serverHello = new ServerHello(new ProtocolVersion(), new Random(), new SessionId(),
+		serverHello = new ServerHello(ProtocolVersion.VERSION_DTLS_1_2, new Random(), new SessionId(),
 				CipherSuite.TLS_PSK_WITH_AES_128_CCM_8, CompressionMethod.NULL, ext, peerAddress);
 	}
 
 	private void givenAServerHelloWithEmptyExtensions() {
-		serverHello = new ServerHello(new ProtocolVersion(), new Random(), new SessionId(),
+		serverHello = new ServerHello(ProtocolVersion.VERSION_DTLS_1_2, new Random(), new SessionId(),
 				CipherSuite.TLS_PSK_WITH_AES_128_CCM_8, CompressionMethod.NULL, new HelloExtensions(), peerAddress);
 	}
 }

scandium-core/src/test/java/org/eclipse/californium/scandium/dtls/cipher/CCMBlockCipherTest.java

@@ -96,7 +96,7 @@ public CCMBlockCipherTest(int payloadLength, int aLength, int nonceLength) {
 	public void setUp() throws Exception {
 		// salt: 32bit client write init vector (can be any four bytes)
 		byte[] client_iv = new byte[]{0x55, 0x23, 0x2F, (byte) 0xA3};
-		ProtocolVersion protocolVer = new ProtocolVersion();
+		ProtocolVersion protocolVer = ProtocolVersion.VERSION_DTLS_1_2;
 		payloadData = new byte[payloadLength];
 		random = new Random(payloadLength);
 		random.nextBytes(payloadData);

scandium-core/src/test/java/org/eclipse/californium/scandium/dtls/cipher/CbcBlockCipherTest.java

@@ -98,7 +98,7 @@ public CbcBlockCipherTest(int payloadLength, int aLength) {
 	@Before
 	public void setUp() throws Exception {
 		// salt: 32bit client write init vector (can be any four bytes)
-		ProtocolVersion protocolVer = new ProtocolVersion();
+		ProtocolVersion protocolVer = ProtocolVersion.VERSION_DTLS_1_2;
 		payloadData = Bytes.createBytes(random, payloadLength);
 
 		// 64bit sequence number, consisting of 16bit epoch (0) + 48bit sequence number (5)