【Exception】IllegalArgumentException: ...The valid characters are defined in RFC 7230 and RFC 3986

案发现场

 java.lang.IllegalArgumentException: Invalid character found in the request target. The valid characters are defined in RFC 7230 and RFC 3986
	at org.apache.coyote.http11.Http11InputBuffer.parseRequestLine(Http11InputBuffer.java:479)
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:687)
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468)
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

原因分析

• Tomcat8.5.30之后的版本，参数中有特殊字符（如：| { }）的话会报错，直接返回400
• RFC（Request For Comments）规范
  • RFC 3986 规范定义了URL中只允许包含英文字母a-zA-Z、数字0-9、-_.~4个特殊字符以及所有保留字符
  • RFC 3986 中指定了以下字符为保留字符：! * ’ ( ) ; : @ & = + $ , / ? # [ ]
  • URL中不允许有 | { }等特殊字符

但在实际生产中还是有些URL可能会携带一些特殊字符，特别是|还是较为常见的。
在 Tomcat 升级到 7 以后，对URL字符的检查都变严格了，如果出现这类字符，Tomcat 将直接返回 400 状态码。

解决方案

Spring Boot 项目

@Configration
public class EmbeddedTomcatConfig implements WebServerFactoryCustomizer<TomcatServletWebServerFactory> {

    @Override
    public void customize(TomcatServletWebServerFactory factory) {
        factory.addConnectorCustomizers(connector -> connector.setAttribute("relaxedQueryChars", "[]"));
    }

}

Tomcat Server
server.xml中修改Connector

<Connector port="8080" protocol="HTTP/1.1"
               connectionTimeout="20000"
			   relaxedQueryChars="[]|{}^&#x5c;&#x60;&quot;&lt;&gt;"
               redirectPort="8443" />