| /* |
| * 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.nio.ByteOrder; |
| import java.util.Collection; |
| import java.util.zip.CRC32; |
| |
| import io.netty.channel.ChannelPipeline; |
| |
| import static org.apache.cassandra.net.Crc.*; |
| |
| /** |
| * Framing format that protects integrity of data in movement with CRCs (of both header and payload). |
| * |
| * 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) |
| * 6. Payload CRC32 (32 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 | |
| * + + |
| * | | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | CRC32 of Payload | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| */ |
| public final class FrameDecoderCrc extends FrameDecoderWith8bHeader |
| { |
| public FrameDecoderCrc(BufferPoolAllocator allocator) |
| { |
| super(allocator); |
| } |
| |
| public static FrameDecoderCrc create(BufferPoolAllocator allocator) |
| { |
| return new FrameDecoderCrc(allocator); |
| } |
| |
| static final int HEADER_LENGTH = 6; |
| private static final int TRAILER_LENGTH = 4; |
| private static final int HEADER_AND_TRAILER_LENGTH = 10; |
| |
| static boolean isSelfContained(long header6b) |
| { |
| return 0 != (header6b & (1L << 17)); |
| } |
| |
| static int payloadLength(long header6b) |
| { |
| return ((int) header6b) & 0x1FFFF; |
| } |
| |
| private static int headerCrc(long header6b) |
| { |
| return ((int) (header6b >>> 24)) & 0xFFFFFF; |
| } |
| |
| static long readHeader6b(ByteBuffer frame, int begin) |
| { |
| long header6b; |
| if (frame.limit() - begin >= 8) |
| { |
| header6b = frame.getLong(begin); |
| if (frame.order() == ByteOrder.BIG_ENDIAN) |
| header6b = Long.reverseBytes(header6b); |
| header6b &= 0xffffffffffffL; |
| } |
| else |
| { |
| header6b = 0; |
| for (int i = 0 ; i < HEADER_LENGTH ; ++i) |
| header6b |= (0xffL & frame.get(begin + i)) << (8 * i); |
| } |
| return header6b; |
| } |
| |
| static CorruptFrame verifyHeader6b(long header6b) |
| { |
| int computeLengthCrc = crc24(header6b, 3); |
| int readLengthCrc = headerCrc(header6b); |
| |
| return readLengthCrc == computeLengthCrc ? null : CorruptFrame.unrecoverable(readLengthCrc, computeLengthCrc); |
| } |
| |
| 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_AND_TRAILER_LENGTH; |
| } |
| |
| final Frame unpackFrame(ShareableBytes bytes, int begin, int end, long header6b) |
| { |
| ByteBuffer in = bytes.get(); |
| boolean isSelfContained = isSelfContained(header6b); |
| |
| CRC32 crc = crc32(); |
| int readFullCrc = in.getInt(end - TRAILER_LENGTH); |
| if (in.order() == ByteOrder.BIG_ENDIAN) |
| readFullCrc = Integer.reverseBytes(readFullCrc); |
| |
| updateCrc32(crc, in, begin + HEADER_LENGTH, end - TRAILER_LENGTH); |
| int computeFullCrc = (int) crc.getValue(); |
| |
| if (readFullCrc != computeFullCrc) |
| return CorruptFrame.recoverable(isSelfContained, (end - begin) - HEADER_AND_TRAILER_LENGTH, readFullCrc, computeFullCrc); |
| |
| return new IntactFrame(isSelfContained, bytes.slice(begin + HEADER_LENGTH, end - TRAILER_LENGTH)); |
| } |
| |
| void decode(Collection<Frame> into, ShareableBytes bytes) |
| { |
| decode(into, bytes, HEADER_LENGTH); |
| } |
| |
| void addLastTo(ChannelPipeline pipeline) |
| { |
| pipeline.addLast("frameDecoderCrc", this); |
| } |
| } |