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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2014 The Netty Project
 *
 * The Netty Project licenses this file to you 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:
 *
 *   https://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 io.netty.handler.codec.http.websocketx;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;

/**
 *
 */
public class Utf8FrameValidator extends ChannelInboundHandlerAdapter {

    private final boolean closeOnProtocolViolation;

    private int fragmentedFramesCount;
    private Utf8Validator utf8Validator;

    public Utf8FrameValidator() {
        this(true);
    }

    public Utf8FrameValidator(boolean closeOnProtocolViolation) {
        this.closeOnProtocolViolation = closeOnProtocolViolation;
    }

    // See https://datatracker.ietf.org/doc/html/rfc6455#section-5.5.
    private static boolean isControlFrame(WebSocketFrame frame) {
        return frame instanceof CloseWebSocketFrame ||
                frame instanceof PingWebSocketFrame ||
                frame instanceof PongWebSocketFrame;
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        if (msg instanceof WebSocketFrame) {
            WebSocketFrame frame = (WebSocketFrame) msg;

            try {
                // Processing for possible fragmented messages for text and binary
                // frames
                if (frame.isFinalFragment()) {
                    // Control frames are allowed between fragments
                    // See https://datatracker.ietf.org/doc/html/rfc6455#section-5.5.
                    if (!isControlFrame(frame)) {

                        // Final frame of the sequence.
                        fragmentedFramesCount = 0;

                        // Check text for UTF8 correctness
                        if (frame instanceof TextWebSocketFrame ||
                                (utf8Validator != null && utf8Validator.isChecking())) {
                            // Check UTF-8 correctness for this payload
                            checkUTF8String(frame.content());

                            // This does a second check to make sure UTF-8
                            // correctness for entire text message
                            utf8Validator.finish();
                        }
                    }
                } else {
                    // Not final frame so we can expect more frames in the
                    // fragmented sequence
                    if (fragmentedFramesCount == 0) {
                        // First text or binary frame for a fragmented set
                        if (frame instanceof TextWebSocketFrame) {
                            checkUTF8String(frame.content());
                        }
                    } else {
                        // Subsequent frames - only check if init frame is text
                        if (utf8Validator != null && utf8Validator.isChecking()) {
                            checkUTF8String(frame.content());
                        }
                    }

                    // Increment counter
                    fragmentedFramesCount++;
                }
            } catch (CorruptedWebSocketFrameException e) {
                protocolViolation(ctx, frame, e);
            }
        }

        super.channelRead(ctx, msg);
    }

    private void checkUTF8String(ByteBuf buffer) {
        if (utf8Validator == null) {
            utf8Validator = new Utf8Validator();
        }
        utf8Validator.check(buffer);
    }

    private void protocolViolation(ChannelHandlerContext ctx, WebSocketFrame frame,
                                   CorruptedWebSocketFrameException ex) {
        frame.release();
        if (closeOnProtocolViolation && ctx.channel().isOpen()) {
            WebSocketCloseStatus closeStatus = ex.closeStatus();
            String reasonText = ex.getMessage();
            if (reasonText == null) {
                reasonText = closeStatus.reasonText();
            }

            CloseWebSocketFrame closeFrame = new CloseWebSocketFrame(closeStatus.code(), reasonText);
            ctx.writeAndFlush(closeFrame).addListener(ChannelFutureListener.CLOSE);
        }

        throw ex;
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        super.exceptionCaught(ctx, cause);
    }
}