Android – Set a VPN connection programmatically on android 4.0

androidandroid-4.0-ice-cream-sandwichvpn

I'm working on programmatically setting a VPN connection on android devices. I was successfully able to do so for devices using OS 2.3.5 and before (I used reflection to get to the hidden classes). But with android 4.0 they got rid of the old classes and use the VPNService class instead.

I figured the best place to start would be to use the ToyVPN example android provided, but I'm facing a lot of challenges with it. In the example code they only needed to send the server address: 

InetSocketAddress server = new InetSocketAddress(mServerAddress, Integer.parseInt(mServerPort));

And then created the VPN tunnel by opening the channel:

tunnel = DatagramChannel.open();

But in my case I need to send the server address, username and password. So far I haven't figured out how to do so. My best guess was to do something like this:

Authenticator.setDefault(new Authenticator(){
        protected PasswordAuthentication getPasswordAuthentication() {
            return new PasswordAuthentication("user","pass".toCharArray());
        }});

    try {
        // Create a DatagramChannel as the VPN tunnel.

        tunnel = DatagramChannel.open();

But this did not work.
so what I'm asking is:

  1. Is there a way, other than what's used in ToyVpn, to create a VPN connection programmatically?
  2. If not, how do I send the credentials when I want to establish a connection to the server?

Edit

I forgot to mention that I need to specify the VPN type (PPTP, L2TP, L2TP/IPSec PSK or L2TP/IPSec CRT).

Best Answer

Basically the VPN API introduced in Android 4.0+ only allows you to implement your own VPN implementation. It does no more than opening the Linux TUN device and pass the file descriptor to you, plus setting up the routes/DNS servers/etc you provided. The whole VPN protocol implementation is solely up to you.

So the short answer is: no. you can't use the VPN API to set up any of the

PPTP, L2TP, L2TP/IPSec PSK or L2TP/IPSec CRT

VPN connections, unless you roll out your own implementation of the mentioned VPN types.

That being said, you may still try to broadcast an Intent to bring your user to the system VPN settings activity and ask them to manually configure/start the VPN.

Oh and one more thing to add. At the time of this writing, Android's latest DevicePolicyManager (API level 21) already provides WiFi settings provisioning support. I would personally guess that Google might continue to add more Android for Work features, which may include VPN provisioning support you need. I/O 2015 is only a few days away so let's wait and see...

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