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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 2019 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.
 */
// (BSD License: https://www.opensource.org/licenses/bsd-license)
//
// Copyright (c) 2011, Joe Walnes and contributors
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or
// without modification, are permitted provided that the
// following conditions are met:
//
// * Redistributions of source code must retain the above
// copyright notice, this list of conditions and the
// following disclaimer.
//
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the
// following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// * Neither the name of the Webbit nor the names of
// its contributors may be used to endorse or promote products
// derived from this software without specific prior written
// permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
// CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.

package io.netty.handler.codec.http.websocketx;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.handler.codec.TooLongFrameException;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;

import java.nio.ByteOrder;
import java.util.List;

import static io.netty.buffer.ByteBufUtil.readBytes;

/**
 * Decodes a web socket frame from wire protocol version 8 format. This code was forked from webbit and modified.
 */
public class WebSocket08FrameDecoder extends ByteToMessageDecoder
        implements WebSocketFrameDecoder {

    enum State {
        READING_FIRST,
        READING_SECOND,
        READING_SIZE,
        MASKING_KEY,
        PAYLOAD,
        CORRUPT
    }

    private static final InternalLogger logger = InternalLoggerFactory.getInstance(WebSocket08FrameDecoder.class);

    private static final byte OPCODE_CONT = 0x0;
    private static final byte OPCODE_TEXT = 0x1;
    private static final byte OPCODE_BINARY = 0x2;
    private static final byte OPCODE_CLOSE = 0x8;
    private static final byte OPCODE_PING = 0x9;
    private static final byte OPCODE_PONG = 0xA;

    private final WebSocketDecoderConfig config;

    private int fragmentedFramesCount;
    private boolean frameFinalFlag;
    private boolean frameMasked;
    private int frameRsv;
    private int frameOpcode;
    private long framePayloadLength;
    private int mask;
    private int framePayloadLen1;
    private boolean receivedClosingHandshake;
    private State state = State.READING_FIRST;

    /**
     * Constructor
     *
     * @param expectMaskedFrames
     *            Web socket servers must set this to true processed incoming masked payload. Client implementations
     *            must set this to false.
     * @param allowExtensions
     *            Flag to allow reserved extension bits to be used or not
     * @param maxFramePayloadLength
     *            Maximum length of a frame's payload. Setting this to an appropriate value for you application
     *            helps check for denial of services attacks.
     */
    public WebSocket08FrameDecoder(boolean expectMaskedFrames, boolean allowExtensions, int maxFramePayloadLength) {
        this(expectMaskedFrames, allowExtensions, maxFramePayloadLength, false);
    }

    /**
     * Constructor
     *
     * @param expectMaskedFrames
     *            Web socket servers must set this to true processed incoming masked payload. Client implementations
     *            must set this to false.
     * @param allowExtensions
     *            Flag to allow reserved extension bits to be used or not
     * @param maxFramePayloadLength
     *            Maximum length of a frame's payload. Setting this to an appropriate value for you application
     *            helps check for denial of services attacks.
     * @param allowMaskMismatch
     *            When set to true, frames which are not masked properly according to the standard will still be
     *            accepted.
     */
    public WebSocket08FrameDecoder(boolean expectMaskedFrames, boolean allowExtensions, int maxFramePayloadLength,
                                   boolean allowMaskMismatch) {
        this(WebSocketDecoderConfig.newBuilder()
            .expectMaskedFrames(expectMaskedFrames)
            .allowExtensions(allowExtensions)
            .maxFramePayloadLength(maxFramePayloadLength)
            .allowMaskMismatch(allowMaskMismatch)
            .build());
    }

    /**
     * Constructor
     *
     * @param decoderConfig
     *            Frames decoder configuration.
     */
    public WebSocket08FrameDecoder(WebSocketDecoderConfig decoderConfig) {
        this.config = ObjectUtil.checkNotNull(decoderConfig, "decoderConfig");
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf in, List out) throws Exception {
        // Discard all data received if closing handshake was received before.
        if (receivedClosingHandshake) {
            in.skipBytes(actualReadableBytes());
            return;
        }

        switch (state) {
        case READING_FIRST:
            if (!in.isReadable()) {
                return;
            }

            framePayloadLength = 0;

            // FIN, RSV, OPCODE
            byte b = in.readByte();
            frameFinalFlag = (b & 0x80) != 0;
            frameRsv = (b & 0x70) >> 4;
            frameOpcode = b & 0x0F;

            if (logger.isTraceEnabled()) {
                logger.trace("Decoding WebSocket Frame opCode={}", frameOpcode);
            }

            state = State.READING_SECOND;
        case READING_SECOND:
            if (!in.isReadable()) {
                return;
            }
            // MASK, PAYLOAD LEN 1
            b = in.readByte();
            frameMasked = (b & 0x80) != 0;
            framePayloadLen1 = b & 0x7F;

            if (frameRsv != 0 && !config.allowExtensions()) {
                protocolViolation(ctx, in, "RSV != 0 and no extension negotiated, RSV:" + frameRsv);
                return;
            }

            if (!config.allowMaskMismatch() && config.expectMaskedFrames() != frameMasked) {
                protocolViolation(ctx, in, "received a frame that is not masked as expected");
                return;
            }

            if (frameOpcode > 7) { // control frame (have MSB in opcode set)

                // control frames MUST NOT be fragmented
                if (!frameFinalFlag) {
                    protocolViolation(ctx, in, "fragmented control frame");
                    return;
                }

                // control frames MUST have payload 125 octets or less
                if (framePayloadLen1 > 125) {
                    protocolViolation(ctx, in, "control frame with payload length > 125 octets");
                    return;
                }

                // check for reserved control frame opcodes
                if (!(frameOpcode == OPCODE_CLOSE || frameOpcode == OPCODE_PING
                      || frameOpcode == OPCODE_PONG)) {
                    protocolViolation(ctx, in, "control frame using reserved opcode " + frameOpcode);
                    return;
                }

                // close frame : if there is a body, the first two bytes of the
                // body MUST be a 2-byte unsigned integer (in network byte
                // order) representing a getStatus code
                if (frameOpcode == 8 && framePayloadLen1 == 1) {
                    protocolViolation(ctx, in, "received close control frame with payload len 1");
                    return;
                }
            } else { // data frame
                // check for reserved data frame opcodes
                if (!(frameOpcode == OPCODE_CONT || frameOpcode == OPCODE_TEXT
                      || frameOpcode == OPCODE_BINARY)) {
                    protocolViolation(ctx, in, "data frame using reserved opcode " + frameOpcode);
                    return;
                }

                // check opcode vs message fragmentation state 1/2
                if (fragmentedFramesCount == 0 && frameOpcode == OPCODE_CONT) {
                    protocolViolation(ctx, in, "received continuation data frame outside fragmented message");
                    return;
                }

                // check opcode vs message fragmentation state 2/2
                if (fragmentedFramesCount != 0 && frameOpcode != OPCODE_CONT) {
                    protocolViolation(ctx, in,
                                      "received non-continuation data frame while inside fragmented message");
                    return;
                }
            }

            state = State.READING_SIZE;
        case READING_SIZE:

            // Read frame payload length
            if (framePayloadLen1 == 126) {
                if (in.readableBytes() < 2) {
                    return;
                }
                framePayloadLength = in.readUnsignedShort();
                if (framePayloadLength < 126) {
                    protocolViolation(ctx, in, "invalid data frame length (not using minimal length encoding)");
                    return;
                }
            } else if (framePayloadLen1 == 127) {
                if (in.readableBytes() < 8) {
                    return;
                }
                framePayloadLength = in.readLong();
                if (framePayloadLength < 0) {
                    protocolViolation(ctx, in, "invalid data frame length (negative length)");
                    return;
                }

                if (framePayloadLength < 65536) {
                    protocolViolation(ctx, in, "invalid data frame length (not using minimal length encoding)");
                    return;
                }
            } else {
                framePayloadLength = framePayloadLen1;
            }

            if (framePayloadLength > config.maxFramePayloadLength()) {
                protocolViolation(ctx, in, WebSocketCloseStatus.MESSAGE_TOO_BIG,
                    "Max frame length of " + config.maxFramePayloadLength() + " has been exceeded.");
                return;
            }

            if (logger.isTraceEnabled()) {
                logger.trace("Decoding WebSocket Frame length={}", framePayloadLength);
            }

            state = State.MASKING_KEY;
        case MASKING_KEY:
            if (frameMasked) {
                if (in.readableBytes() < 4) {
                    return;
                }
                mask = in.readInt();
            }
            state = State.PAYLOAD;
        case PAYLOAD:
            if (in.readableBytes() < framePayloadLength) {
                return;
            }

            ByteBuf payloadBuffer = Unpooled.EMPTY_BUFFER;
            try {
                if (framePayloadLength > 0) {
                    payloadBuffer = readBytes(ctx.alloc(), in, toFrameLength(framePayloadLength));
                }

                // Now we have all the data, the next checkpoint must be the next
                // frame
                state = State.READING_FIRST;

                // Unmask data if needed
                if (frameMasked & framePayloadLength > 0) {
                    unmask(payloadBuffer);
                }

                // Processing ping/pong/close frames because they cannot be
                // fragmented
                if (frameOpcode == OPCODE_PING) {
                    out.add(new PingWebSocketFrame(frameFinalFlag, frameRsv, payloadBuffer));
                    payloadBuffer = null;
                    return;
                }
                if (frameOpcode == OPCODE_PONG) {
                    out.add(new PongWebSocketFrame(frameFinalFlag, frameRsv, payloadBuffer));
                    payloadBuffer = null;
                    return;
                }
                if (frameOpcode == OPCODE_CLOSE) {
                    receivedClosingHandshake = true;
                    checkCloseFrameBody(ctx, payloadBuffer);
                    out.add(new CloseWebSocketFrame(frameFinalFlag, frameRsv, payloadBuffer));
                    payloadBuffer = null;
                    return;
                }

                // Processing for possible fragmented messages for text and binary
                // frames
                if (frameFinalFlag) {
                    // Final frame of the sequence. Apparently ping frames are
                    // allowed in the middle of a fragmented message
                    fragmentedFramesCount = 0;
                } else {
                    // Increment counter
                    fragmentedFramesCount++;
                }

                // Return the frame
                if (frameOpcode == OPCODE_TEXT) {
                    out.add(new TextWebSocketFrame(frameFinalFlag, frameRsv, payloadBuffer));
                    payloadBuffer = null;
                    return;
                } else if (frameOpcode == OPCODE_BINARY) {
                    out.add(new BinaryWebSocketFrame(frameFinalFlag, frameRsv, payloadBuffer));
                    payloadBuffer = null;
                    return;
                } else if (frameOpcode == OPCODE_CONT) {
                    out.add(new ContinuationWebSocketFrame(frameFinalFlag, frameRsv,
                                                           payloadBuffer));
                    payloadBuffer = null;
                    return;
                } else {
                    throw new UnsupportedOperationException("Cannot decode web socket frame with opcode: "
                                                            + frameOpcode);
                }
            } finally {
                if (payloadBuffer != null) {
                    payloadBuffer.release();
                }
            }
        case CORRUPT:
            if (in.isReadable()) {
                // If we don't keep reading Netty will throw an exception saying
                // we can't return null if no bytes read and state not changed.
                in.readByte();
            }
            return;
        default:
            throw new Error("Shouldn't reach here.");
        }
    }

    private void unmask(ByteBuf frame) {
        int i = frame.readerIndex();
        int end = frame.writerIndex();

        ByteOrder order = frame.order();

        int intMask = mask;
        // Avoid sign extension on widening primitive conversion
        long longMask = intMask & 0xFFFFFFFFL;
        longMask |= longMask << 32;

        for (int lim = end - 7; i < lim; i += 8) {
            frame.setLong(i, frame.getLong(i) ^ longMask);
        }

        if (i < end - 3) {
            frame.setInt(i, frame.getInt(i) ^ (int) longMask);
            i += 4;
        }

        if (order == ByteOrder.LITTLE_ENDIAN) {
            intMask = Integer.reverseBytes(intMask);
        }

        int maskOffset = 0;
        for (; i < end; i++) {
            frame.setByte(i, frame.getByte(i) ^ WebSocketUtil.byteAtIndex(intMask, maskOffset++ & 3));
        }
    }

    private void protocolViolation(ChannelHandlerContext ctx, ByteBuf in, String reason) {
        protocolViolation(ctx, in, WebSocketCloseStatus.PROTOCOL_ERROR, reason);
    }

    private void protocolViolation(ChannelHandlerContext ctx, ByteBuf in, WebSocketCloseStatus status, String reason) {
        protocolViolation(ctx, in, new CorruptedWebSocketFrameException(status, reason));
    }

    private void protocolViolation(ChannelHandlerContext ctx, ByteBuf in, CorruptedWebSocketFrameException ex) {
        state = State.CORRUPT;
        int readableBytes = in.readableBytes();
        if (readableBytes > 0) {
            // Fix for memory leak, caused by ByteToMessageDecoder#channelRead:
            // buffer 'cumulation' is released ONLY when no more readable bytes available.
            in.skipBytes(readableBytes);
        }
        if (ctx.channel().isActive() && config.closeOnProtocolViolation()) {
            Object closeMessage;
            if (receivedClosingHandshake) {
                closeMessage = Unpooled.EMPTY_BUFFER;
            } else {
                WebSocketCloseStatus closeStatus = ex.closeStatus();
                String reasonText = ex.getMessage();
                if (reasonText == null) {
                    reasonText = closeStatus.reasonText();
                }
                closeMessage = new CloseWebSocketFrame(closeStatus, reasonText);
            }
            ctx.writeAndFlush(closeMessage).addListener(ChannelFutureListener.CLOSE);
        }
        throw ex;
    }

    private static int toFrameLength(long l) {
        if (l > Integer.MAX_VALUE) {
            throw new TooLongFrameException("Length:" + l);
        } else {
            return (int) l;
        }
    }

    /** */
    protected void checkCloseFrameBody(
            ChannelHandlerContext ctx, ByteBuf buffer) {
        if (buffer == null || !buffer.isReadable()) {
            return;
        }
        if (buffer.readableBytes() < 2) {
            protocolViolation(ctx, buffer, WebSocketCloseStatus.INVALID_PAYLOAD_DATA, "Invalid close frame body");
        }

        // Must have 2 byte integer within the valid range
        int statusCode = buffer.getShort(buffer.readerIndex());
        if (!WebSocketCloseStatus.isValidStatusCode(statusCode)) {
            protocolViolation(ctx, buffer, "Invalid close frame getStatus code: " + statusCode);
        }

        // May have UTF-8 message
        if (buffer.readableBytes() > 2) {
            try {
                new Utf8Validator().check(buffer, buffer.readerIndex() + 2, buffer.readableBytes() - 2);
            } catch (CorruptedWebSocketFrameException ex) {
                protocolViolation(ctx, buffer, ex);
            }
        }
    }
}
    

    

    

            

    

            



    
    






    
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