如何使用Spring RestTemplate禁用SSL证书检查？

Question

我正在尝试编写一个集成测试，其中我们的测试使用Simple启动一个嵌入式HTTPS服务器。我使用创建了自签名证书，keytool并能够使用浏览器（特别是Chrome浏览器）访问服务器，并且收到有关自签名证书的警告。

但是，当我尝试使用Spring RestTemplate进行连接时，出现ResourceAccessException：

org.springframework.web.client.ResourceAccessException: I/O error on GET request for "https://localhost:8088":sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target; nested exception is 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 org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:557)
    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:502)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:444)
    at net.initech.DummySslServer.shouldConnect(DummySslServer.java:119)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:160)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:74)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:211)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:67)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)
Caused by: 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:1917)
    at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:301)
    at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:295)
    at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1369)
    at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:156)
    at sun.security.ssl.Handshaker.processLoop(Handshaker.java:925)
    at sun.security.ssl.Handshaker.process_record(Handshaker.java:860)
    at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1043)
    at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1343)
    at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1371)
    at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1355)
    at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:563)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:153)
    at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:78)
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48)
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:52)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:541)
    ... 33 more
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:387)
    at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:292)
    at sun.security.validator.Validator.validate(Validator.java:260)
    at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324)
    at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:229)
    at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:124)
    at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1351)
    ... 47 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:145)
    at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:131)
    at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)
    at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:382)
    ... 53 more

从其他问题和博客 文章中，我已经看到了HostnameVerifier用类似以下内容代替的建议

private static final HostnameVerifier PROMISCUOUS_VERIFIER = ( s, sslSession ) -> true;

而且我已经在全球范围内和RestTemplate本身设置了它：

HttpsURLConnection.setDefaultHostnameVerifier( PROMISCUOUS_VERIFIER );

…及其RestTemplate本身：

final RestTemplate restTemplate = new RestTemplate();
restTemplate.setRequestFactory( new SimpleClientHttpRequestFactory() {
    @Override
    protected void prepareConnection(HttpURLConnection connection, String httpMethod) throws IOException {
        if(connection instanceof HttpsURLConnection ){
            ((HttpsURLConnection) connection).setHostnameVerifier(PROMISCUOUS_VERIFIER);
        }
        super.prepareConnection(connection, httpMethod);
    }
});

但是，我仍然遇到上述错误。我该如何解决？

1. 不能在单元测试之外本地安装证书，因为那样将需要在每台开发机和构建服务器上手动安装证书，并且会导致大量繁琐的手续。
2. 我们需要SSL，因为我们正在测试位于其顶部的库，RestTemplate并且我们对其进行了正确配置。
   我正在使用Java 8（但可以使用7）和Spring 4.0.3。
   

Answer 1

我希望我仍然有指向该方向的资源链接，但这是最终为我工作的代码。通过查看X509TrustManager的JavaDoc，看起来TrustManager工作方式是在成功验证后不返回任何内容，否则抛出异常。因此，使用null实现时，它将被视为成功验证。然后，你删除所有其他实现。

import javax.net.ssl.*;
import java.security.*;
import java.security.cert.X509Certificate;

public final class SSLUtil{

    private static final TrustManager[] UNQUESTIONING_TRUST_MANAGER = new TrustManager[]{
            new X509TrustManager() {
                public java.security.cert.X509Certificate[] getAcceptedIssuers(){
                    return null;
                }
                public void checkClientTrusted( X509Certificate[] certs, String authType ){}
                public void checkServerTrusted( X509Certificate[] certs, String authType ){}
            }
        };

    public  static void turnOffSslChecking() throws NoSuchAlgorithmException, KeyManagementException {
        // Install the all-trusting trust manager
        final SSLContext sc = SSLContext.getInstance("SSL");
        sc.init( null, UNQUESTIONING_TRUST_MANAGER, null );
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
    }

    public static void turnOnSslChecking() throws KeyManagementException, NoSuchAlgorithmException {
        // Return it to the initial state (discovered by reflection, now hardcoded)
        SSLContext.getInstance("SSL").init( null, null, null );
    }

    private SSLUtil(){
        throw new UnsupportedOperationException( "Do not instantiate libraries.");
    }
}