| /* |
| * 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.servicecomb.foundation.vertx.server; |
| |
| import java.io.UnsupportedEncodingException; |
| |
| import io.netty.buffer.ByteBuf; |
| import io.vertx.core.Handler; |
| import io.vertx.core.buffer.Buffer; |
| import io.vertx.core.parsetools.RecordParser; |
| |
| /** |
| * TcpParser |
| * |
| * |
| */ |
| public class TcpParser implements Handler<Buffer> { |
| public static final byte[] TCP_MAGIC; |
| |
| public static final int TCP_HEADER_LENGTH = 23; |
| |
| static { |
| try { |
| TCP_MAGIC = "CSE.TCP".getBytes("UTF-8"); |
| } catch (UnsupportedEncodingException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| |
| enum ParseStatus { |
| TCP_HEADER, |
| TCP_PAYLOAD |
| } |
| |
| private TcpBufferHandler outputHandler; |
| |
| private RecordParser parser; |
| |
| private ParseStatus status; |
| |
| private long msgId; |
| |
| // 仅仅是header + body,不包括headerLen本身 |
| private int totalLen; |
| |
| private int headerLen; |
| |
| public TcpParser(TcpBufferHandler output) { |
| this.outputHandler = output; |
| |
| reset(); |
| } |
| |
| /** |
| * 在解析出错时,通过重新创建parser对象,将整个缓冲区重置 |
| */ |
| protected void reset() { |
| parser = RecordParser.newFixed(TCP_HEADER_LENGTH, this::onParse); |
| status = ParseStatus.TCP_HEADER; |
| |
| parser.handle(Buffer.buffer(0)); |
| } |
| |
| public boolean firstNEqual(byte[] a, byte[] b, int n) { |
| assert a.length >= n && b.length >= n; |
| |
| for (int i = 0; i < n; i++) { |
| if (a[i] != b[i]) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| protected void onParse(Buffer buffer) { |
| switch (status) { |
| case TCP_HEADER: |
| ByteBuf buf = buffer.getByteBuf(); |
| if (!firstNEqual(TCP_MAGIC, buf.array(), TCP_MAGIC.length)) { |
| reset(); |
| return; |
| } |
| |
| buf.skipBytes(TCP_MAGIC.length); |
| msgId = buf.readLong(); |
| totalLen = buf.readInt(); |
| headerLen = buf.readInt(); |
| if (headerLen > totalLen || headerLen <= 0) { |
| throw new IllegalStateException("possibly attack."); |
| } |
| |
| if (totalLen == 0) { |
| onReadOnePackage(null, null); |
| return; |
| } |
| |
| parser.fixedSizeMode(totalLen); |
| status = ParseStatus.TCP_PAYLOAD; |
| break; |
| |
| case TCP_PAYLOAD: |
| Buffer headerBuffer = buffer.slice(0, headerLen); |
| Buffer bodyBuffer = buffer.slice(headerLen, buffer.length()); |
| onReadOnePackage(headerBuffer, bodyBuffer); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| |
| private void onReadOnePackage(Buffer headerBuffer, Buffer bodyBuffer) { |
| outputHandler.handle(msgId, headerBuffer, bodyBuffer); |
| |
| parser.fixedSizeMode(TCP_HEADER_LENGTH); |
| status = ParseStatus.TCP_HEADER; |
| } |
| |
| public void handle(Buffer buf) { |
| parser.handle(buf); |
| } |
| } |