以编程方式添加证书颁发机构,同时保留Android系统SSL证书

Question

StackOverflow上有很多关于这个主题的问题,但我似乎找不到与我的问题相关的问题.

我有一个需要与HTTPS服务器通信的Android应用程序:一些与在Android系统密钥库中注册的CA(常见的HTTPS网站)签名,一些使用我拥有但不在Android系统密钥库(具有例如,自动签名证书).

我知道如何以编程方式添加我的CA并强制每个HTTPS连接使用它.我使用以下代码:

public class SslCertificateAuthority {

    public static void addCertificateAuthority(InputStream inputStream) {

        try {
            // Load CAs from an InputStream
            // (could be from a resource or ByteArrayInputStream or ...)
            CertificateFactory cf = CertificateFactory.getInstance("X.509");
            InputStream caInput = new BufferedInputStream(inputStream);
            Certificate ca;
            try {
                ca = cf.generateCertificate(caInput);
            } finally {
                caInput.close();
            }

            // Create a KeyStore containing our trusted CAs
            String keyStoreType = KeyStore.getDefaultType();
            KeyStore keyStore = KeyStore.getInstance(keyStoreType);
            keyStore.load(null, null);
            keyStore.setCertificateEntry("ca", ca);

            // Create a TrustManager that trusts the CAs in our KeyStore
            String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
            TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
            tmf.init(keyStore);

            // Create an SSLContext that uses our TrustManager
            SSLContext context = SSLContext.getInstance("TLS");
            context.init(null, tmf.getTrustManagers(), null);

            // Tell the URLConnection to use a SocketFactory from our SSLContext
            HttpsURLConnection.setDefaultSSLSocketFactory(context.getSocketFactory());
        } catch (CertificateException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (KeyStoreException e) {
            e.printStackTrace();
        } catch (KeyManagementException e) {
            e.printStackTrace();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }  

    }

}

但是,这样做会禁用Android系统密钥库的使用,我无法再查询与其他CA签名的HTTPS站点.

我尝试在Android密钥库中添加我的CA,使用:

KeyStore.getInstance("AndroidCAStore")

...但我无法在其中添加我的CA(启动了一个例外).

当我必须使用CA时,我可以使用实例方法HttpsURLConnection.setSSLSocketFactory(...)而不是静态全局HttpsURLConnection.setDefaultSSLSocketFactory(...)来逐个判断.

但它根本不实用,因为有时我无法将预配置的HttpsURLConnection对象传递给某些库.

关于我如何做到这一点的一些想法？

---

编辑 - 答案

好的,按照给定的建议,这是我的工作代码.它可能需要一些增强功能,但它似乎是一个起点.

public class SslCertificateAuthority {

    private static class UnifiedTrustManager implements X509TrustManager {
        private X509TrustManager defaultTrustManager;
        private X509TrustManager localTrustManager;
        public UnifiedTrustManager(KeyStore localKeyStore) throws KeyStoreException {
            try {
                this.defaultTrustManager = createTrustManager(null);
                this.localTrustManager = createTrustManager(localKeyStore);
            } catch (NoSuchAlgorithmException e) {
                e.printStackTrace();
            }
        }
        private X509TrustManager createTrustManager(KeyStore store) throws NoSuchAlgorithmException, KeyStoreException {
            String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
            TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
            tmf.init((KeyStore) store);
            TrustManager[] trustManagers = tmf.getTrustManagers();
            return (X509TrustManager) trustManagers[0];
        }
        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            try {
                defaultTrustManager.checkServerTrusted(chain, authType);
            } catch (CertificateException ce) {
                localTrustManager.checkServerTrusted(chain, authType);
            }
        }
        @Override
        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
            try {
                defaultTrustManager.checkClientTrusted(chain, authType);
            } catch (CertificateException ce) {
                localTrustManager.checkClientTrusted(chain, authType);
            }
        }
        @Override
        public X509Certificate[] getAcceptedIssuers() {
            X509Certificate[] first = defaultTrustManager.getAcceptedIssuers();
            X509Certificate[] second = localTrustManager.getAcceptedIssuers();
            X509Certificate[] result = Arrays.copyOf(first, first.length + second.length);
            System.arraycopy(second, 0, result, first.length, second.length);
            return result;
        }
    }

    public static void setCustomCertificateAuthority(InputStream inputStream) {

        try {
            // Load CAs from an InputStream
            // (could be from a resource or ByteArrayInputStream or ...)
            CertificateFactory cf = CertificateFactory.getInstance("X.509");
            InputStream caInput = new BufferedInputStream(inputStream);
            Certificate ca;
            try {
                ca = cf.generateCertificate(caInput);
                System.out.println("ca=" + ((X509Certificate) ca).getSubjectDN());
            } finally {
                caInput.close();
            }

            // Create a KeyStore containing our trusted CAs
            String keyStoreType = KeyStore.getDefaultType();
            KeyStore keyStore = KeyStore.getInstance(keyStoreType);
            keyStore.load(null, null);
            keyStore.setCertificateEntry("ca", ca);

            // Create a TrustManager that trusts the CAs in our KeyStore and system CA
            UnifiedTrustManager trustManager = new UnifiedTrustManager(keyStore);

            // Create an SSLContext that uses our TrustManager
            SSLContext context = SSLContext.getInstance("TLS");
            context.init(null, new TrustManager[]{trustManager}, null);

            // Tell the URLConnection to use a SocketFactory from our SSLContext
            HttpsURLConnection.setDefaultSSLSocketFactory(context.getSocketFactory());

        } catch (CertificateException e) {
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (KeyStoreException e) {
            e.printStackTrace();
        } catch (KeyManagementException e) {
            e.printStackTrace();
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}

Answer 1

这是一个老问题，但我遇到了同样的问题，所以可能值得发布我的答案。您尝试将证书添加到KeyStore.getInstance("AndroidCAStore")，但遇到异常。实际上，您应该做相反的事情 - 将密钥库中的条目添加到您创建的密钥库中。我的代码与你的有点不同，我只是为了完整的答案而发布它，尽管只有中间部分很重要。

KeyStore keyStore=KeyStore.getInstance("BKS");
InputStream in=activity.getResources().openRawResource(R.raw.my_ca);
try
{
  keyStore.load(in,"PASSWORD_HERE".toCharArray());
}
finally
{
  in.close();
}
KeyStore defaultCAs=KeyStore.getInstance("AndroidCAStore");
if(defaultCAs!=null)
{
  defaultCAs.load(null,null);
  Enumeration<String> keyAliases=defaultCAs.aliases();
  while(keyAliases.hasMoreElements())
  {
    String alias=keyAliases.nextElement();
    Certificate cert=defaultCAs.getCertificate(alias);
    try
    {
      if(!keyStore.containsAlias(alias))
        keyStore.setCertificateEntry(alias,cert);
    }
    catch(Exception e)
    {
      System.out.println("Error adding "+e);
    }
  }
}
TrustManagerFactory tmf=TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
tmf.init(keyStore);
// Get a new SSL context
SSLContext ctx = SSLContext.getInstance("SSL");
ctx.init(null,tmf.getTrustManagers(),new java.security.SecureRandom());
return ctx.getSocketFactory();

Answer 2

这可能为时已晚，但这是一种经过尝试和测试的方法，有助于绕过 Java 进行的证书检查。

我不能声称这段代码是我的功劳，它是我的一位同事编写的:)。它可以在开发过程中用于测试您的代码。如果您根本不想处理证书，您可以使 Java 始终为您的 HttpURLConnection 对象提供来自任何主机的证书。这似乎正是您在这里尝试做的事情。

这是一个可以帮助您做到这一点的课程：

import javax.net.ssl.*;
import java.net.HttpURLConnection;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

/***
 * Should only be used in development, this class will allow connections to an HTTPS server with unverified certificates. 
 * obviously this should not be used in the real world
 */
public class TrustModifier {
private static final TrustingHostnameVerifier TRUSTING_HOSTNAME_VERIFIER = new TrustingHostnameVerifier();
private static SSLSocketFactory factory;

/**
 * Call this with any HttpURLConnection, and it will modify the trust settings if it is an HTTPS connection.
 *
 * @param conn the {@link HttpURLConnection} instance
 * @throws KeyManagementException   if an error occurs while initializing the context object for the TLS protocol
 * @throws NoSuchAlgorithmException if no Provider supports a TrustManagerFactorySpi implementation for the TLS protocol.
 */
public static void relaxHostChecking(HttpURLConnection conn) throws KeyManagementException, NoSuchAlgorithmException {
    if (conn instanceof HttpsURLConnection) {
        HttpsURLConnection httpsConnection = (HttpsURLConnection) conn;
        SSLSocketFactory factory = prepFactory();
        httpsConnection.setSSLSocketFactory(factory);
        httpsConnection.setHostnameVerifier(TRUSTING_HOSTNAME_VERIFIER);
    }
}

 /**
 * Returns an {@link SSLSocketFactory} instance for the protocol being passed, this represents a secure communication context
 *
 * @return a {@link SSLSocketFactory} object for the TLS protocol
 * @throws NoSuchAlgorithmException if no Provider supports a TrustManagerFactorySpi implementation for the specified protocol.
 * @throws KeyManagementException   if an error occurs while initializing the context object
 */
static synchronized SSLSocketFactory prepFactory() throws NoSuchAlgorithmException, KeyManagementException {
    if (factory == null) {
        SSLContext ctx = SSLContext.getInstance("TLS");
        ctx.init(null, new TrustManager[]{new AlwaysTrustManager()}, null);
        factory = ctx.getSocketFactory();
    }
    return factory;
}

private static final class TrustingHostnameVerifier implements HostnameVerifier {
    public boolean verify(String hostname, SSLSession session) {
        return true;
    }
}

private static class AlwaysTrustManager implements X509TrustManager {
    public void checkClientTrusted(X509Certificate[] arg0, String arg1) throws CertificateException {
    }

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

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

您需要做的就是像这样调用函数relaxHostChecking()：

    if (conn instanceof HttpsURLConnection) {
        TrustModifier.relaxHostChecking(conn);
    }

这将导致 java 信任您尝试使用 HttpURLConnection 连接到的任何主机。