如何使用Apache HttpClient处理无效的SSL证书？

Question

我知道，关于这个问题有很多不同的问题和很多答案…但是我听不懂…

我已经：从关闭“按原样”安装了ubuntu-9.10-desktop-amd64 + NetBeans6.7.1。代表 我需要通过HTTPS连接到某个站点。为此，我使用Apache的HttpClient。

从教程中我读到：

“一旦正确安装了JSSE，通过SSL的安全HTTP通信就应该
与普通HTTP通信一样简单。” 还有一些例子：

HttpClient httpclient = new HttpClient();
GetMethod httpget = new GetMethod("https://www.verisign.com/"); 
try { 
  httpclient.executeMethod(httpget);
  System.out.println(httpget.getStatusLine());
} finally {
  httpget.releaseConnection();
}

现在，我写这个：

HttpClient client = new HttpClient();

HttpMethod get = new GetMethod("https://mms.nw.ru");
//get.setDoAuthentication(true);

try {
    int status = client.executeMethod(get);
    System.out.println(status);

    BufferedInputStream is = new BufferedInputStream(get.getResponseBodyAsStream());
    int r=0;byte[] buf = new byte[10];
    while((r = is.read(buf)) > 0) {
        System.out.write(buf,0,r);
    }

} catch(Exception ex) {
    ex.printStackTrace();
}

结果，我有一系列错误：

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
        at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
        at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1627)
        at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:204)
        at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:198)
        at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:994)
        at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:142)
        at sun.security.ssl.Handshaker.processLoop(Handshaker.java:533)
        at sun.security.ssl.Handshaker.process_record(Handshaker.java:471)
        at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:904)
        at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1132)
        at sun.security.ssl.SSLSocketImpl.writeRecord(SSLSocketImpl.java:643)
        at sun.security.ssl.AppOutputStream.write(AppOutputStream.java:78)
        at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:82)
        at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:140)
        at org.apache.commons.httpclient.HttpConnection.flushRequestOutputStream(HttpConnection.java:828)
        at org.apache.commons.httpclient.HttpMethodBase.writeRequest(HttpMethodBase.java:2116)
        at org.apache.commons.httpclient.HttpMethodBase.execute(HttpMethodBase.java:1096)
        at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:398)
        at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171)
        at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397)
        at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:323)
        at simpleapachehttp.Main.main(Main.java:41)
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:302)
        at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:205)
        at sun.security.validator.Validator.validate(Validator.java:235)
        at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:147)
        at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:230)
        at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:270)
        at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:973)
        ... 17 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:191)
        at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:255)
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:297)
        ... 23 more

我该怎么做才能创建最简单的SSL连接？（可能同时没有KeyManager和Trust Manager等。）

Answer 1

你需要执行以下操作之一：

• 使用接受任何证书的TrustManager配置SSLContext（请参阅下文）
• 使用包含你的证书的适当信任库配置SSLContext
• 将该站点的证书添加到默认的Java信任库中。

这是一个示例程序，该程序创建一个接受任何证书的（几乎一文不值的）SSL上下文：

import java.net.URL;
import java.security.SecureRandom;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.KeyManager;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

public class SSLTest {

    public static void main(String [] args) throws Exception {
        // configure the SSLContext with a TrustManager
        SSLContext ctx = SSLContext.getInstance("TLS");
        ctx.init(new KeyManager[0], new TrustManager[] {new DefaultTrustManager()}, new SecureRandom());
        SSLContext.setDefault(ctx);

        URL url = new URL("https://mms.nw.ru");
        HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
        conn.setHostnameVerifier(new HostnameVerifier() {
            @Override
            public boolean verify(String arg0, SSLSession arg1) {
                return true;
            }
        });
        System.out.println(conn.getResponseCode());
        conn.disconnect();
    }

    private static class DefaultTrustManager implements X509TrustManager {

        @Override
        public void checkClientTrusted(X509Certificate[] arg0, String arg1) throws CertificateException {}

        @Override
        public void checkServerTrusted(X509Certificate[] arg0, String arg1) throws CertificateException {}

        @Override
        public X509Certificate[] getAcceptedIssuers() {
            return null;
        }
    }
}