我正在尝试在我的Android应用程序中使用客户端证书，以便我只能与使用该应用程序或拥有该证书的人员进行HTTPS通信。
我的res / raw文件夹中有证书。当我开始输入＆＃34; R.raw。＆＃34;
时，Android Studio会看到它但是，当我使用以下任何代码时，变量会返回为＆＃34; null＆＃34;值：
FileInputStream fis = null;
fis = (FileInputStream) getClass().getResourceAsStream(String.valueOf(R.raw.clientcert2));
或
InputStream fis = getClass().getResourceAsStream("raw/clientcert2.p12");
或
InputStream fis = null;
fis= (InputStream) getResources().openRawResource(R.raw.clientcert2);
最后一个实际上崩溃了应用程序，这让我觉得它甚至没有接近正确。它崩溃时出现以下错误：
09-10 08:13:06.677 10310-10310/com.example.agenice.clientcert E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.agenice.clientcert, PID: 10310
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.agenice.clientcert/com.example.agenice.clientcert.MainActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at android.content.ContextWrapper.getResources(ContextWrapper.java:89)
at android.view.ContextThemeWrapper.getResources(ContextThemeWrapper.java:78)
at com.example.agenice.clientcert.GetCert.getThisCert(MainActivity.java:92)
at com.example.agenice.clientcert.MainActivity.onCreate(MainActivity.java:58)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
作为旁注 - 是的，我知道如果有人获得APK，他们只需解压缩包并获取证书即可。这就是为什么这不是应用程序的最终形式。这是该过程中唯一的第一步。在iOS版本的App中，我能够导入p12文件，将二进制文件转换为字符串，将字符串导出到日志中，然后将其用作证书。这消除了将证书文件添加到应用程序的需要。所以，这就是整个事情的发展方向。如果有人能够快速简便地做到这一点，那就太好了。现在，我只需要弄清楚为什么这部分不起作用。
谢谢！
答案 0 :(得分：1)
更新NullPointerException
在 logcat 信息中，getResources()中的GetCert.getThisCert()导致了NullPointerException。您好像没有将Context从活动传递到GetCert课程。因此，请更新您的代码并检查结果。
END OF UPDATE
您可以参考我的以下代码：
private TrustManager[] getWrappedTrustManagers(TrustManager[] trustManagers) {
final X509TrustManager originalTrustManager = (X509TrustManager) trustManagers[0];
return new TrustManager[]{
new X509TrustManager() {
public X509Certificate[] getAcceptedIssuers() {
return originalTrustManager.getAcceptedIssuers();
}
public void checkClientTrusted(X509Certificate[] certs, String authType) {
try {
originalTrustManager.checkClientTrusted(certs, authType);
} catch (CertificateException e) {
e.printStackTrace();
}
}
public void checkServerTrusted(X509Certificate[] certs, String authType) {
try {
originalTrustManager.checkServerTrusted(certs, authType);
} catch (CertificateException e) {
e.printStackTrace();
}
}
}
};
}
private SSLSocketFactory getSSLSocketFactory_Certificate(String keyStoreType, int keystoreResId)
throws CertificateException, KeyStoreException, IOException, NoSuchAlgorithmException, KeyManagementException {
CertificateFactory cf = CertificateFactory.getInstance("X.509");
InputStream caInput = getResources().openRawResource(keystoreResId);
Certificate ca = cf.generateCertificate(caInput);
caInput.close();
if (keyStoreType == null || keyStoreType.length() == 0) {
keyStoreType = KeyStore.getDefaultType();
}
KeyStore keyStore = KeyStore.getInstance(keyStoreType);
keyStore.load(null, null);
keyStore.setCertificateEntry("ca", ca);
String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
tmf.init(keyStore);
TrustManager[] wrappedTrustManagers = getWrappedTrustManagers(tmf.getTrustManagers());
SSLContext sslContext = SSLContext.getInstance("TLS");
sslContext.init(null, wrappedTrustManagers, null);
return sslContext.getSocketFactory();
}
private SSLSocketFactory getSSLSocketFactory_KeyStore(String keyStoreType, int keystoreResId, String keyPassword)
throws CertificateException, KeyStoreException, IOException, NoSuchAlgorithmException, KeyManagementException {
InputStream caInput = getResources().openRawResource(keystoreResId);
// creating a KeyStore containing trusted CAs
if (keyStoreType == null || keyStoreType.length() == 0) {
keyStoreType = KeyStore.getDefaultType();
}
KeyStore keyStore = KeyStore.getInstance(keyStoreType);
keyStore.load(caInput, keyPassword.toCharArray());
// creating a TrustManager that trusts the CAs in the KeyStore
String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
tmf.init(keyStore);
TrustManager[] wrappedTrustManagers = getWrappedTrustManagers(tmf.getTrustManagers());
SSLContext sslContext = SSLContext.getInstance("TLS");
sslContext.init(null, wrappedTrustManagers, null);
return sslContext.getSocketFactory();
}
然后调用以下两个中的一个（一个用于密钥库文件，另一个用于证书文件）：
SSLSocketFactory sslSocketFactory = getSSLSocketFactory_KeyStore("BKS", R.raw.androidbksv1, "123456789");
SSLSocketFactory sslSocketFactory = getSSLSocketFactory_Certificate("BKS", R.raw.androidbksv1_cert);
由于您拥有 PKCS12 文件，因此您可以使用以下两种方法之一：
SSLSocketFactory sslSocketFactory = getSSLSocketFactory_KeyStore("PKCS12", R.raw.androidpkcs12, "123456789");
SSLSocketFactory sslSocketFactory = getSSLSocketFactory_Certificate("PKCS12", R.raw.androidpkcs12_cert);
以上代码已在我的HTTPS项目中成功测试过。希望这有帮助！
此外，请澄清The last one actually crashes the app...，发布更多代码和logcat信息（如果有）。