Enable TLS 1.1 and TLS 1.2 on Android 4.1-4.4

Summary:
This is a proposed patch for issue facebook#7192.

Android 4.1-4.4 has support for TLS 1.1 and 1.2 but it is disabled by default. Because of the known security issues and more and more servers switching to TLS 1.2 only, it would be nice for react-native to enable this support.

I demonstrated a demo application which showcases the problem and can be used to test this patch. All sources and documentation for it can be found here:

https://github.com/bringnow/react-native-tls-test

Credits to Alex Gotev (gotev) for the nice implementation.
Closes facebook#9840

Differential Revision: D4099446

Pulled By: lacker

fbshipit-source-id: 94db320dce6d27f98169e63f834562360c00eef7

ReactAndroid/src/main/java/com/facebook/react/modules/network/OkHttpClientProvider.java

@@ -9,11 +9,19 @@
 
 package com.facebook.react.modules.network;
 
+import android.os.Build;
+
+import com.facebook.common.logging.FLog;
+
+import java.util.ArrayList;
+import java.util.List;
 import java.util.concurrent.TimeUnit;
 
 import javax.annotation.Nullable;
 
+import okhttp3.ConnectionSpec;
 import okhttp3.OkHttpClient;
+import okhttp3.TlsVersion;
 
 /**
  * Helper class that provides the same OkHttpClient instance that will be used for all networking
@@ -39,11 +47,41 @@ public static void replaceOkHttpClient(OkHttpClient client) {
 
   private static OkHttpClient createClient() {
     // No timeouts by default
-    return new OkHttpClient.Builder()
+    OkHttpClient.Builder client = new OkHttpClient.Builder()
       .connectTimeout(0, TimeUnit.MILLISECONDS)
       .readTimeout(0, TimeUnit.MILLISECONDS)
       .writeTimeout(0, TimeUnit.MILLISECONDS)
-      .cookieJar(new ReactCookieJarContainer())
-      .build();
+      .cookieJar(new ReactCookieJarContainer());
+
+    return enableTls12OnPreLollipop(client).build();
   }
+
+  /*
+    On Android 4.1-4.4 (API level 16 to 19) TLS 1.1 and 1.2 are
+    available but not enabled by default. The following method
+    enables it.
+   */
+  public static OkHttpClient.Builder enableTls12OnPreLollipop(OkHttpClient.Builder client) {
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN && 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) {
+        FLog.e("OkHttpClientProvider", "Error while enabling TLS 1.2", exc);
+      }
+    }
+
+    return client;
+  }
+
 }

ReactAndroid/src/main/java/com/facebook/react/modules/network/TLSSocketFactory.java

@@ -0,0 +1,78 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+package com.facebook.react.modules.network;
+
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.Socket;
+import java.net.UnknownHostException;
+import java.security.KeyManagementException;
+import java.security.NoSuchAlgorithmException;
+
+import javax.net.ssl.SSLContext;
+import javax.net.ssl.SSLSocket;
+import javax.net.ssl.SSLSocketFactory;
+
+/**
+ *
+ * This class is needed for TLS 1.2 support on Android 4.x
+ *
+ * Source: http://blog.dev-area.net/2015/08/13/android-4-1-enable-tls-1-1-and-tls-1-2/
+ */
+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;
+    }
+}