Java tutorial
/******************************************************************************* * Copyright (c) 2016 comtel inc. * * Licensed under the Apache License, version 2.0 (the "License"); you may not use this file except * in compliance with the License. You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software distributed under the License * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express * or implied. See the License for the specific language governing permissions and limitations under * the License. *******************************************************************************/ package org.jfxvnc.net.rfb.codec; import java.util.Arrays; import org.jfxvnc.net.rfb.codec.decoder.ProtocolVersionDecoder; import org.jfxvnc.net.rfb.codec.handshaker.RfbClientHandshaker; import org.jfxvnc.net.rfb.codec.handshaker.RfbClientHandshakerFactory; import org.jfxvnc.net.rfb.codec.handshaker.event.SecurityResultEvent; import org.jfxvnc.net.rfb.codec.handshaker.event.SecurityTypesEvent; import org.jfxvnc.net.rfb.codec.handshaker.event.ServerInitEvent; import org.jfxvnc.net.rfb.codec.handshaker.event.SharedEvent; import org.jfxvnc.net.rfb.codec.security.RfbSecurityHandshaker; import org.jfxvnc.net.rfb.codec.security.RfbSecurityHandshakerFactory; import org.jfxvnc.net.rfb.codec.security.RfbSecurityMessage; import org.jfxvnc.net.rfb.codec.security.SecurityType; import org.jfxvnc.net.rfb.exception.ProtocolException; import org.jfxvnc.net.rfb.render.ProtocolConfiguration; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import io.netty.buffer.Unpooled; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.channel.ChannelPipeline; public class ProtocolHandshakeHandler extends ChannelInboundHandlerAdapter { private static Logger logger = LoggerFactory.getLogger(ProtocolHandshakeHandler.class); private RfbClientHandshaker handshaker; private RfbSecurityHandshaker secHandshaker; private final ProtocolConfiguration config; public ProtocolHandshakeHandler(ProtocolConfiguration config) { this.config = config; } @Override public void channelActive(final ChannelHandlerContext ctx) throws Exception { ctx.pipeline().addBefore(ctx.name(), "rfb-version-decoder", new ProtocolVersionDecoder()); } @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { if (msg instanceof ProtocolVersion) { handleServerVersion(ctx, (ProtocolVersion) msg); return; } if (msg instanceof SecurityTypesEvent) { handleSecurityTypes(ctx, (SecurityTypesEvent) msg); return; } if (msg instanceof RfbSecurityMessage) { handleSecurityMessage(ctx, (RfbSecurityMessage) msg); return; } if (msg instanceof SecurityResultEvent) { handleSecurityResult(ctx, (SecurityResultEvent) msg); return; } if (msg instanceof ServerInitEvent) { handshaker.finishHandshake(ctx.channel(), config.versionProperty().get()); ChannelPipeline cp = ctx.pipeline(); cp.fireUserEventTriggered(ProtocolState.HANDSHAKE_COMPLETE); cp.remove(this); cp.fireChannelRead(msg); return; } throw new ProtocolException("unknown message occurred: " + msg); } private void handleServerVersion(final ChannelHandlerContext ctx, ProtocolVersion version) { logger.debug("server version: {}", version); if (version.isGreaterThan(config.versionProperty().get())) { logger.debug("set client version: {}", config.versionProperty().get()); version = config.versionProperty().get(); } RfbClientHandshakerFactory hsFactory = new RfbClientHandshakerFactory(); handshaker = hsFactory.newRfbClientHandshaker(version); handshaker.handshake(ctx.channel()).addListener((future) -> { if (!future.isSuccess()) { ctx.fireExceptionCaught(future.cause()); } else { ctx.pipeline().fireUserEventTriggered(ProtocolState.HANDSHAKE_STARTED); } }); } private void handleSecurityTypes(final ChannelHandlerContext ctx, SecurityTypesEvent msg) { SecurityType[] supportTypes = msg.getSecurityTypes(); if (supportTypes.length == 0) { ctx.fireExceptionCaught(new ProtocolException("no security types supported")); return; } SecurityType userSecType = config.securityProperty().get(); boolean isSupported = Arrays.stream(supportTypes).anyMatch(i -> i == userSecType); if (!isSupported) { ctx.fireExceptionCaught(new ProtocolException( String.format("Authentication: '%s' is not supported. The server supports only (%s)", userSecType, Arrays.toString(supportTypes)))); return; } if (userSecType == SecurityType.NONE) { logger.debug("none security type available"); ctx.writeAndFlush(Unpooled.buffer(1).writeByte(userSecType.getType())); ctx.pipeline().fireUserEventTriggered(ProtocolState.SECURITY_COMPLETE); return; } RfbSecurityHandshakerFactory secFactory = new RfbSecurityHandshakerFactory(); secHandshaker = secFactory.newRfbSecurityHandshaker(userSecType); if (secHandshaker == null) { ctx.fireExceptionCaught( new ProtocolException(String.format("Authentication: '%s' is not supported yet", userSecType))); return; } secHandshaker.handshake(ctx.channel(), msg.isResponse()).addListener((future) -> { if (future.isSuccess()) { ctx.pipeline().fireUserEventTriggered(ProtocolState.SECURITY_STARTED); } else { ctx.fireExceptionCaught(future.cause()); } }); } private void handleSecurityMessage(final ChannelHandlerContext ctx, final RfbSecurityMessage msg) { msg.setCredentials(config); ctx.writeAndFlush(msg).addListener((future) -> { if (secHandshaker != null && !secHandshaker.isHandshakeComplete()) { secHandshaker.finishHandshake(ctx.channel(), msg); } if (!future.isSuccess()) { ctx.fireExceptionCaught(future.cause()); } }); } private void handleSecurityResult(final ChannelHandlerContext ctx, final SecurityResultEvent msg) { if (msg.isPassed()) { logger.info("security passed: {}", msg); boolean sharedFlag = config.sharedProperty().get(); ctx.writeAndFlush(new SharedEvent(sharedFlag)).addListener((future) -> { if (!future.isSuccess()) { ctx.fireExceptionCaught(future.cause()); } else { ctx.pipeline().fireUserEventTriggered(ProtocolState.SECURITY_COMPLETE); } }); return; } ctx.pipeline().fireUserEventTriggered(ProtocolState.SECURITY_FAILED); if (msg.getThrowable() != null) { ctx.fireExceptionCaught(msg.getThrowable()); } } }