Enable TLS 1.2 in Android 4.4

Fabio Piunti picture Fabio Piunti · Aug 25, 2017 · Viewed 9.9k times · Source

I use Retrofit and OkHttp3 for making requests. I konw that in Android 4.4 TLS 1.1 and TLS 1.2 are not enabled by defult. So i'm trying to enable them. But so far i had no sucsess. I read that it could be a problem of the android studio emulator, but i can't make a test on a real device with andoroid 4.4 rigthnow

This is what i have done so far:

private <S> S createService(Class<S> serviceClass) {
    Retrofit retrofit = builder.client(getNewHttpClient()).build();
    return retrofit.create(serviceClass);
}

private OkHttpClient getNewHttpClient() {
    OkHttpClient.Builder clientBuilder = new OkHttpClient.Builder()
            .connectTimeout(10, TimeUnit.SECONDS)
            .writeTimeout(10, TimeUnit.SECONDS)
            .readTimeout(0, TimeUnit.MINUTES); // Disable timeouts for read

    return enableTls12OnPreLollipop(clientBuilder).build();
}


public static OkHttpClient.Builder enableTls12OnPreLollipop(OkHttpClient.Builder client) {
    if (Build.VERSION.SDK_INT == Build.VERSION_CODES.KITKAT) {
        try {
            client.sslSocketFactory(new TLSSocketFactory());

            ConnectionSpec cs = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
                    .tlsVersions(TlsVersion.TLS_1_2)
                    .build();

            List<ConnectionSpec> specs = new ArrayList<>();
            specs.add(cs);
            specs.add(ConnectionSpec.COMPATIBLE_TLS);
            specs.add(ConnectionSpec.CLEARTEXT);

            client.connectionSpecs(specs);
        } catch (Exception exc) {
            Log.e("OkHttpClientProvider", "Error while enabling TLS 1.2", exc);
        }
    }

    return client;
}

TLSSocketFactory CLASS

public class TLSSocketFactory extends SSLSocketFactory {
private SSLSocketFactory delegate;

public TLSSocketFactory() throws KeyManagementException, NoSuchAlgorithmException {
    SSLContext context = SSLContext.getInstance("TLS");
    context.init(null, null, null);
    delegate = context.getSocketFactory();
}

@Override
public String[] getDefaultCipherSuites() {
    return delegate.getDefaultCipherSuites();
}

@Override
public String[] getSupportedCipherSuites() {
    return delegate.getSupportedCipherSuites();
}

@Override
public Socket createSocket(Socket s, String host, int port, boolean autoClose) throws IOException {
    return enableTLSOnSocket(delegate.createSocket(s, host, port, autoClose));
}

@Override
public Socket createSocket(String host, int port) throws IOException, UnknownHostException {
    return enableTLSOnSocket(delegate.createSocket(host, port));
}

@Override
public Socket createSocket(String host, int port, InetAddress localHost, int localPort) throws IOException, UnknownHostException {
    return enableTLSOnSocket(delegate.createSocket(host, port, localHost, localPort));
}

@Override
public Socket createSocket(InetAddress host, int port) throws IOException {
    return enableTLSOnSocket(delegate.createSocket(host, port));
}

@Override
public Socket createSocket(InetAddress address, int port, InetAddress localAddress, int localPort) throws IOException {
    return enableTLSOnSocket(delegate.createSocket(address, port, localAddress, localPort));
}

private Socket enableTLSOnSocket(Socket socket) {
    if(socket != null && (socket instanceof SSLSocket)) {
        ((SSLSocket)socket).setEnabledProtocols(new String[] {"TLSv1.1", "TLSv1.2"});
    }
    return socket;
}
}

I have tried this but did not work.

My Error is: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0xb829bae0: Failure in SSL library, usually a protocol error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure (external/openssl/ssl/s23_clnt.c:741 0x8d9e3990:0x00000000)

Answer

Aleksander Mielczarek picture Aleksander Mielczarek · Aug 25, 2017

Please try this: https://developer.android.com/training/articles/security-gms-provider.html.

It is using https://developers.google.com/android/reference/com/google/android/gms/security/ProviderInstaller, you need to have Google API in your project.

You need to just call in your Application:

@Override
public void onCreate() {
    super.onCreate();
    try {
        ProviderInstaller.installIfNeeded(this);
    } catch (GooglePlayServicesRepairableException | GooglePlayServicesNotAvailableException e) {
        e.printStackTrace();
    }
}

You should also remove your custom SSLfactory.