private boolean failed = false;

private static final byte[] closehandshake = { -1, 0 };

private final Random reuseableRandom = new Random();

public static byte[] createChallenge( String key1, String key2, byte[] key3 ) throws InvalidHandshakeException {

byte[] part1 = getPart( key1 );

byte[] part2 = getPart( key2 );

byte[] challenge = new byte[ 16 ];

challenge[ 0 ] = part1[ 0 ];

challenge[ 1 ] = part1[ 1 ];

challenge[ 2 ] = part1[ 2 ];

challenge[ 3 ] = part1[ 3 ];

challenge[ 4 ] = part2[ 0 ];

challenge[ 5 ] = part2[ 1 ];

challenge[ 6 ] = part2[ 2 ];

challenge[ 7 ] = part2[ 3 ];

challenge[ 8 ] = key3[ 0 ];

challenge[ 9 ] = key3[ 1 ];

challenge[ 10 ] = key3[ 2 ];

challenge[ 11 ] = key3[ 3 ];

challenge[ 12 ] = key3[ 4 ];

challenge[ 13 ] = key3[ 5 ];

challenge[ 14 ] = key3[ 6 ];

challenge[ 15 ] = key3[ 7 ];

MessageDigest md5;

try {

md5 = MessageDigest.getInstance( "MD5" );

} catch ( NoSuchAlgorithmException e ) {

throw new RuntimeException( e );

}

return md5.digest( challenge );

}

private static String generateKey() {

Random r = new Random();

long maxNumber = 4294967295L;

long spaces = r.nextInt( 12 ) + 1;

int max = new Long( maxNumber / spaces ).intValue();

max = Math.abs( max );

int number = r.nextInt( max ) + 1;

long product = number * spaces;

String key = Long.toString( product );

// always insert atleast one random character

int numChars = r.nextInt( 12 ) + 1;

for( int i = 0 ; i < numChars ; i++ ) {

int position = r.nextInt( key.length() );

position = Math.abs( position );

char randChar = (char) ( r.nextInt( 95 ) + 33 );

// exclude numbers here

if( randChar >= 48 && randChar <= 57 ) {

randChar -= 15;

}

key = new StringBuilder( key ).insert( position, randChar ).toString();

}

for( int i = 0 ; i < spaces ; i++ ) {

int position = r.nextInt( key.length() - 1 ) + 1;

position = Math.abs( position );

key = new StringBuilder( key ).insert( position, "\u0020" ).toString();

}

return key;

}

private static byte[] getPart( String key ) throws InvalidHandshakeException {

try {

long keyNumber = Long.parseLong( key.replaceAll( "[^0-9]", "" ) );

long keySpace = key.split( "\u0020" ).length - 1;

if( keySpace == 0 ) {

throw new InvalidHandshakeException( "invalid Sec-WebSocket-Key (/key2/)" );

}

long part = keyNumber / keySpace;

return new byte[]{ (byte) ( part >> 24 ), (byte) ( ( part << 8 ) >> 24 ), (byte) ( ( part << 16 ) >> 24 ), (byte) ( ( part << 24 ) >> 24 ) };

} catch ( NumberFormatException e ) {

throw new InvalidHandshakeException( "invalid Sec-WebSocket-Key (/key1/ or /key2/)" );

}

}

@Override

public HandshakeState acceptHandshakeAsClient( ClientHandshake request, ServerHandshake response ) {

if( failed ) {

return HandshakeState.NOT_MATCHED;

}

try {

if( !response.getFieldValue( "Sec-WebSocket-Origin" ).equals( request.getFieldValue( "Origin" ) ) || !basicAccept( response ) ) {

return HandshakeState.NOT_MATCHED;

}

byte[] content = response.getContent();

if( content == null || content.length == 0 ) {

throw new IncompleteHandshakeException();

}

if( Arrays.equals( content, createChallenge( request.getFieldValue( "Sec-WebSocket-Key1" ), request.getFieldValue( "Sec-WebSocket-Key2" ), request.getContent() ) ) ) {

return HandshakeState.MATCHED;

} else {

return HandshakeState.NOT_MATCHED;

}

} catch ( InvalidHandshakeException e ) {

throw new RuntimeException( "bad handshakerequest", e );

}

}

@Override

public HandshakeState acceptHandshakeAsServer( ClientHandshake handshakedata ) {

if( handshakedata.getFieldValue( "Upgrade" ).equals( "WebSocket" ) && handshakedata.getFieldValue( "Connection" ).contains( "Upgrade" ) && handshakedata.getFieldValue( "Sec-WebSocket-Key1" ).length() > 0 && handshakedata.getFieldValue( "Sec-WebSocket-Key2" ).length() > 0 && handshakedata.hasFieldValue( "Origin" ) )

return HandshakeState.MATCHED;

return HandshakeState.NOT_MATCHED;

}

@Override

public ClientHandshakeBuilder postProcessHandshakeRequestAsClient( ClientHandshakeBuilder request ) {

request.put( "Upgrade", "WebSocket" );

request.put( "Connection", "Upgrade" );

request.put( "Sec-WebSocket-Key1", generateKey() );

request.put( "Sec-WebSocket-Key2", generateKey() );

if( !request.hasFieldValue( "Origin" ) ) {

request.put( "Origin", "random" + reuseableRandom.nextInt() );

}

byte[] key3 = new byte[ 8 ];

reuseableRandom.nextBytes( key3 );

request.setContent( key3 );

return request;

}

@Override

public HandshakeBuilder postProcessHandshakeResponseAsServer( ClientHandshake request, ServerHandshakeBuilder response ) throws InvalidHandshakeException {

response.setHttpStatusMessage( "WebSocket Protocol Handshake" );

response.put( "Upgrade", "WebSocket" );

response.put( "Connection", request.getFieldValue( "Connection" ) ); // to respond to a Connection keep alive

response.put( "Sec-WebSocket-Origin", request.getFieldValue( "Origin" ) );

String location = "ws://" + request.getFieldValue( "Host" ) + request.getResourceDescriptor();

response.put( "Sec-WebSocket-Location", location );

String key1 = request.getFieldValue( "Sec-WebSocket-Key1" );

String key2 = request.getFieldValue( "Sec-WebSocket-Key2" );

byte[] key3 = request.getContent();

if( key1 == null || key2 == null || key3 == null || key3.length != 8 ) {

throw new InvalidHandshakeException( "Bad keys" );

}

response.setContent( createChallenge( key1, key2, key3 ) );

return response;

}

@Override

public Handshakedata translateHandshake( ByteBuffer buf ) throws InvalidHandshakeException {

HandshakeBuilder bui = translateHandshakeHttp( buf, role );

// the first drafts are lacking a protocol number which makes them difficult to distinguish. Sec-WebSocket-Key1 is typical for draft76

if( ( bui.hasFieldValue( "Sec-WebSocket-Key1" ) || role == Role.CLIENT ) && !bui.hasFieldValue( "Sec-WebSocket-Version" ) ) {

byte[] key3 = new byte[ role == Role.SERVER ? 8 : 16 ];

try {

buf.get( key3 );

} catch ( BufferUnderflowException e ) {

throw new IncompleteHandshakeException( buf.capacity() + 16 );

}

bui.setContent( key3 );

}

return bui;

}

@Override

public List<Framedata> translateFrame( ByteBuffer buffer ) throws InvalidDataException {

buffer.mark();

List<Framedata> frames = super.translateRegularFrame( buffer );

if( frames == null ) {

buffer.reset();

frames = readyframes;

readingState = true;

if( currentFrame == null )

currentFrame = ByteBuffer.allocate( 2 );

else {

throw new InvalidFrameException();

}

if( buffer.remaining() > currentFrame.remaining() ) {

throw new InvalidFrameException();

} else {

currentFrame.put( buffer );

}

if( !currentFrame.hasRemaining() ) {

if( Arrays.equals( currentFrame.array(), closehandshake ) ) {

CloseFrame closeFrame = new CloseFrame();

closeFrame.setCode(CloseFrame.NORMAL);

closeFrame.isValid();

frames.add(closeFrame);

return frames;

}

else{

throw new InvalidFrameException();

}

} else {

readyframes = new LinkedList<Framedata>();

return frames;

}

} else {

return frames;

}

}

@Override

public ByteBuffer createBinaryFrame( Framedata framedata ) {

if( framedata.getOpcode() == Opcode.CLOSING )

return ByteBuffer.wrap( closehandshake );

return super.createBinaryFrame( framedata );

}

@Override

public CloseHandshakeType getCloseHandshakeType() {

return CloseHandshakeType.ONEWAY;

}

@Override

public Draft copyInstance() {

return new Draft_76();

}