Create a KeyStore instance with my self signed certificate

Question

I have a self-signed certificate that I use to communicate with my server. As per the this article I can create a Keystore instance with my certificate. I did the same and the code is working just fine, I am able to make server calls over HTTPS connection.

When I print all the certificates that are present in the Keystore it is printing only the certificates that I have inserted into it. I thought that this implementation will instruct android to trust all the in-built certificates in the AndroidCAStore and the new self-signed certificate from my server.

When creating an instance I used AndroidCAStore and AndroidKeyStore but the problem is I am not able to add my self-signed certificate to the keystore. Whenever I call setCertificateEntry I am getting UnsupportedMethodException .

I want to create a KeyStore that has all the default certificate from the Android default keystore and the Self-Signed certificate from my server. How to do that?

Answer 1

public static class CustomTrustManager implements X509TrustManager{

    private X509TrustManager defaultTrustManager;
    private X509TrustManager localTrustManager;

    public CustomTrustManager(KeyStore keyStore){
        try {
            defaultTrustManager = createTrustManager(null);
            localTrustManager = createTrustManager(keyStore);
        }catch (NoSuchAlgorithmException e){
            Log.e("CustomTrustManager"," Cannot create trust manager : NoSuchAlgorithm found "+e.toString());
        }catch (KeyStoreException exp){
            Log.e("CustomTrustManager"," Cannot create trust manager : Keystore exception"+e.toString());
        }
    }
    @Override
    public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
        try {
            localTrustManager.checkClientTrusted(x509Certificates, s);
        } catch (CertificateException ce) {
            defaultTrustManager.checkClientTrusted(x509Certificates, s);
        }
    }

    @Override
    public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
        Log.e("CustomTrustManager","Checking server trust");
        try {
            localTrustManager.checkServerTrusted(x509Certificates, s);
        } catch (CertificateException ce) {
            defaultTrustManager.checkServerTrusted(x509Certificates, s);
        }
    }

    @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;
    }

    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];
    }
}