Android Adding File Certificate To Retrofit 2.0+

After the previous post about how to adding file certificate to Retrofit 1.7, today i gonna share a new tutorial about how to adding file certificate to Retrofit 2.0.

As you know, one of usage of file certificate is used to access HTTPS from HTTP. If your current host is HTTPS but you still access using HTTP , so by using file certificate it will be redirecting to HTTPS automatically.

Before you adding file certificate to Retrofit 2.0 make you using OKHTTP 3 for your client. So here is the method that you can use for adding file certificate to Retrofit 2.0 :

First import the following package :

	import java.io.IOException;
	import java.io.InputStream;
	import java.security.KeyManagementException;
	import java.security.KeyStore;
	import java.security.KeyStoreException;
	import java.security.NoSuchAlgorithmException;
	import java.security.cert.Certificate;
	import java.security.cert.CertificateException;
	import java.security.cert.CertificateFactory;
	import javax.net.ssl.SSLContext;
	import javax.net.ssl.TrustManagerFactory;
	import okhttp3.OkHttpClient;

view raw pacakge.java hosted with ❤ by GitHub

Here the method that i use in my project, write the following method (you can modify the method as you wish) :

	private OkHttpClient setClient() {
	OkHttpClient.Builder okHttpClient = new OkHttpClient.Builder();
	// loading CAs from an InputStream
	CertificateFactory cf = null;
	try {
	cf = CertificateFactory.getInstance("X.509");
	InputStream cert = MyApplication.getContext().getResources().openRawResource(R.raw.your_file_cert);
	Certificate ca;
	try {
	ca = cf.generateCertificate(cert);
	} finally { cert.close(); }
	// creating a KeyStore containing our trusted CAs
	String keyStoreType = KeyStore.getDefaultType();
	KeyStore keyStore = KeyStore.getInstance(keyStoreType);
	keyStore.load(null, null);
	keyStore.setCertificateEntry("ca", ca);
	// creating a TrustManager that trusts the CAs in our KeyStore
	String tmfAlgorithm = TrustManagerFactory.getDefaultAlgorithm();
	TrustManagerFactory tmf = TrustManagerFactory.getInstance(tmfAlgorithm);
	tmf.init(keyStore);
	// creating an SSLSocketFactory that uses our TrustManager
	SSLContext sslContext = SSLContext.getInstance("TLS");
	sslContext.init(null, tmf.getTrustManagers(), null);
	// okHttpClient.setSslSocketFactory(sslContext.getSocketFactory());
	okHttpClient.sslSocketFactory(sslContext.getSocketFactory());
	} catch (CertificateException e) {
	e.printStackTrace();
	} catch (NoSuchAlgorithmException e) {
	e.printStackTrace();
	} catch (KeyStoreException e) {
	e.printStackTrace();
	} catch (KeyManagementException e) {
	e.printStackTrace();
	} catch (IOException e) {
	e.printStackTrace();
	}
	return okHttpClient.build();
	}

view raw setClient.java hosted with ❤ by GitHub

That's all, hope it helps and works. Thank you.