httpclient向HTTPS发送数据建立SSL连接时的异常-木庄网络博客

本文摘自PHP中文网，作者巴扎黑，侵删。

异常信息如下：

javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

原因：服务器的证书不被信任。一般是这样造成的。

使用KEYTOOL工具创建证书，然后用TOMCAT启动后，在浏览器打开网站时，会出现证书不被信任的提示。当然，利用HTTPCLIENT向服务端HTTPS发送数据时，HTTPCLIENT也会检测服务端的证书是否被信任，不被信任就抛出上面的异常。

解决办法有两种，一种是使证书被客户端信任。另一种是使用HTTPCLIENT发送数据时不检测服务器证书是否可信。

第一种办法，使证书被信任。

找正规CA签发证书，或者自己签发证书（只能那一台客户机上可信）。找正规CA签发证书就不说了，自己签发证书呢，见我的其他文章。

我发现，自己签名的证书弄好之后，从客户端打开服务端地址时，不再提示上面的错误，但是还是不能发送数据。原因是什么呢？因为那台证书在客户端操作系统上可信，但是在JAVA的KEYSTORE里不可信，要把服务端的证书导入KEYSTORE库中

导入办法：

打开命令行窗口，并到<java-home>\lib\security\ 目录下，运行下面的命令：

keytool -import -noprompt -keystore cacerts -storepass changeit -alias yourEntry1 -file your.cer

最后一个是服务端导出的证书，其他可以默认。

要注意的是，如果客户端电脑上装有许多个JAVA版本，要确定你导入的证书的JAVA版本是你TOMCAT使用的那个，一般TOMCAT使用的是环境变量指向的那个JAVA版本。

如果是在ECLIPSE中建立的TOMCAT服务器，新建时会要你选择默认JRE还是指向的JAVA，这里一定要选指向刚才导入的那个JAVA的路径，不然，你导入的证书库也没效果。

第二种办法，使用HTTPCLIENT时不检测服务器证书是否可信

扩展HttpClient 类实现自动接受证书

因为这种方法自动接收所有证书，因此存在一定的安全问题，所以在使用这种方法前请仔细考虑您的系统的安全需求。具体的步骤如下：

?提供一个自定义的socket factory （test.MySecureProtocolSocketFactory ）。这个自定义的类必须实现接口org.apache.commons.httpclient.protocol.SecureProtocolSocketFactory ，在实现接口的类中调用自定义的X509TrustManager(test.MyX509TrustManager) ，这两个类可以在随本文带的附件中得到

?创建一个org.apache.commons.httpclient.protocol.Protocol 的实例，指定协议名称和默认的端口号

Protocol myhttps = new Protocol("https", new MySecureProtocolSocketFactory (), 443);

?注册刚才创建的https 协议对象

Protocol.registerProtocol("https ", myhttps);

?然后按照普通编程方式打开https 的目标地址，代码如下：

MySecureProtocolSocketFactory.java

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import java.io.IOException;  
    import java.net.InetAddress;  
    import java.net.InetSocketAddress;  
    import java.net.Socket;  
    import java.net.SocketAddress;  
    import java.net.UnknownHostException;  
    import java.security.KeyManagementException;  
    import java.security.NoSuchAlgorithmException;  
    import java.security.cert.CertificateException;  
    import java.security.cert.X509Certificate;  
       
    import javax.net.SocketFactory;  
    import javax.net.ssl.SSLContext;  
    import javax.net.ssl.TrustManager;  
    import javax.net.ssl.X509TrustManager;  
       
    import org.apache.commons.httpclient.ConnectTimeoutException;  
    import org.apache.commons.httpclient.params.HttpConnectionParams;  
    import org.apache.commons.httpclient.protocol.SecureProtocolSocketFactory;  
       
    public class MySecureProtocolSocketFactory implements SecureProtocolSocketFactory {  
        private SSLContext sslcontext = null;  
           
        private SSLContext createSSLContext() {  
            SSLContext sslcontext=null;  
            try {  
                sslcontext = SSLContext.getInstance("SSL");  
                sslcontext.init(null, new TrustManager[]{new TrustAnyTrustManager()}, new java.security.SecureRandom());  
            } catch (NoSuchAlgorithmException e) {  
                e.printStackTrace();  
            } catch (KeyManagementException e) {  
                e.printStackTrace();  
            }  
            return sslcontext;  
        }  
           
        private SSLContext getSSLContext() {  
            if (this.sslcontext == null) {  
                this.sslcontext = createSSLContext();  
            }  
            return this.sslcontext;  
        }  
           
        public Socket createSocket(Socket socket, String host, int port, boolean autoClose)  
                throws IOException, UnknownHostException {  
            return getSSLContext().getSocketFactory().createSocket(  
                    socket,  
                    host,  
                    port,  
                    autoClose  
                );  
        }  
       
        public Socket createSocket(String host, int port) throws IOException,  
                UnknownHostException {  
            return getSSLContext().getSocketFactory().createSocket(  
                    host,  
                    port  
                );  
        }  
           
           
        public Socket createSocket(String host, int port, InetAddress clientHost, int clientPort)  
                throws IOException, UnknownHostException {  
            return getSSLContext().getSocketFactory().createSocket(host, port, clientHost, clientPort);  
        }  
       
        public Socket createSocket(String host, int port, InetAddress localAddress,  
                int localPort, HttpConnectionParams params) throws IOException,  
                UnknownHostException, ConnectTimeoutException {  
            if (params == null) {  
                throw new IllegalArgumentException("Parameters may not be null");  
            }  
            int timeout = params.getConnectionTimeout();  
            SocketFactory socketfactory = getSSLContext().getSocketFactory();  
            if (timeout == 0) {  
                return socketfactory.createSocket(host, port, localAddress, localPort);  
            } else {  
                Socket socket = socketfactory.createSocket();  
                SocketAddress localaddr = new InetSocketAddress(localAddress, localPort);  
                SocketAddress remoteaddr = new InetSocketAddress(host, port);  
                socket.bind(localaddr);  
                socket.connect(remoteaddr, timeout);  
                return socket;  
            }  
        }  
           
        //自定义私有类  
        private static class TrustAnyTrustManager implements X509TrustManager {  
              
            public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {  
            }  
          
            public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {  
            }  
          
            public X509Certificate[] getAcceptedIssuers() {  
                return new X509Certificate[]{};  
            }  
        }  
           
       
    }