| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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 |
| * |
| * 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.apache.cassandra.net; |
| |
| import java.nio.ByteBuffer; |
| import java.util.Collection; |
| |
| import io.netty.channel.ChannelPipeline; |
| |
| import static org.apache.cassandra.net.FrameDecoderCrc.HEADER_LENGTH; |
| import static org.apache.cassandra.net.FrameDecoderCrc.isSelfContained; |
| import static org.apache.cassandra.net.FrameDecoderCrc.payloadLength; |
| import static org.apache.cassandra.net.FrameDecoderCrc.readHeader6b; |
| import static org.apache.cassandra.net.FrameDecoderCrc.verifyHeader6b; |
| |
| /** |
| * A frame decoder for unprotected frames, i.e. those without any modification or payload protection. |
| * This is non-standard, and useful for systems that have a trusted transport layer that want |
| * to avoid incurring the (very low) cost of computing a CRC. All we do is accumulate the bytes |
| * of the frame, verify the frame header, and pass through the bytes stripped of the header. |
| * |
| * Every on-wire frame contains: |
| * 1. Payload length (17 bits) |
| * 2. {@code isSelfContained} flag (1 bit) |
| * 3. Header padding (6 bits) |
| * 4. CRC24 of the header (24 bits) |
| * 5. Payload (up to 2 ^ 17 - 1 bits) |
| * |
| * 0 1 2 3 |
| * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | Payload Length |C| | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * CRC24 of Header | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + |
| * | | |
| * + + |
| * | Payload | |
| * + + |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| */ |
| final class FrameDecoderUnprotected extends FrameDecoderWith8bHeader |
| { |
| FrameDecoderUnprotected(BufferPoolAllocator allocator) |
| { |
| super(allocator); |
| } |
| |
| public static FrameDecoderUnprotected create(BufferPoolAllocator allocator) |
| { |
| return new FrameDecoderUnprotected(allocator); |
| } |
| |
| final long readHeader(ByteBuffer frame, int begin) |
| { |
| return readHeader6b(frame, begin); |
| } |
| |
| final CorruptFrame verifyHeader(long header6b) |
| { |
| return verifyHeader6b(header6b); |
| } |
| |
| final int frameLength(long header6b) |
| { |
| return payloadLength(header6b) + HEADER_LENGTH; |
| } |
| |
| final Frame unpackFrame(ShareableBytes bytes, int begin, int end, long header6b) |
| { |
| boolean isSelfContained = isSelfContained(header6b); |
| return new IntactFrame(isSelfContained, bytes.slice(begin + HEADER_LENGTH, end)); |
| } |
| |
| void decode(Collection<Frame> into, ShareableBytes bytes) |
| { |
| decode(into, bytes, HEADER_LENGTH); |
| } |
| |
| void addLastTo(ChannelPipeline pipeline) |
| { |
| pipeline.addLast("frameDecoderUnprotected", this); |
| } |
| } |