## Configure IPsec/XAuth VPN Clients

*Read this in other languages: [English](clients-xauth.md), [简体中文](clients-xauth-zh.md).*

*To connect using IPsec/L2TP mode, see: [Configure IPsec/L2TP VPN Clients](clients.md)*

After <a href="https://github.com/hwdsl2/setup-ipsec-vpn" target="_blank">setting up your own VPN server</a>, follow these steps to configure your devices. IPsec/XAuth is natively supported by Android, iOS and OS X. There is no additional software to install. Windows users can use the free <a href="https://www.shrew.net/download/vpn" target="_blank">Shrew Soft client</a>. In case you are unable to connect, first check to make sure the VPN credentials were entered correctly.

`IPsec/XAuth` mode is also called `Cisco IPsec`. Compared to `IPsec/L2TP`, it is generally faster with less overhead.

---
* Platforms
  * [Windows](#windows)
  * [OS X](#os-x)
  * [Android](#android)
  * [iOS](#ios)

### Windows ###

**Note:** You can also connect using [IPsec/L2TP mode](clients.md). No additional software is required.

1. Download and install the free <a href="https://www.shrew.net/download/vpn" target="_blank">Shrew Soft VPN client</a>.
1. Click Start Menu -> All Programs -> ShrewSoft VPN Client -> VPN Access Manager
1. Click the **Add (+)** button on toolbar.
1. Enter `Your VPN Server IP` in the **Host Name or IP Address** field.
1. Click the **Authentication** tab. Select **Mutual PSK + XAuth** from the **Authentication Method** drop-down menu.
1. Click the **Credentials** tab below. Enter `Your VPN IPsec PSK` in the **Pre Shared Key** field.
1. Click the **Phase 1** tab. Select **main** from the **Exchange Type** drop-down menu.
1. Click **Save** to save the VPN connection details.
1. Select the new VPN connection. Click the **Connect** button on toolbar.
1. Enter `Your VPN Username` in the **Username** field.
1. Enter `Your VPN Password` in the **Password** field.
1. Click **Connect**.

Once connected, you will see **tunnel enabled** in the VPN Connect status window. You can verify that your traffic is being routed properly by <a href="https://encrypted.google.com/search?q=my+ip" target="_blank">looking up your IP address on Google</a>. It should say "Your public IP address is `Your VPN Server IP`".

**Note:** A <a href="https://documentation.meraki.com/MX-Z/Client_VPN/Troubleshooting_Client_VPN#Windows_Error_809" target="_blank">one-time registry change</a> is required if the VPN server and/or client is behind NAT (e.g. home router). Please refer to the linked page, or run the following from an <a href="http://windows.microsoft.com/en-us/windows/command-prompt-faq#1TC=windows-7" target="_blank">elevated command prompt</a>. You must reboot your computer when done.
- For Windows Vista, 7, 8 and 10
  ```console
  REG ADD HKLM\SYSTEM\CurrentControlSet\Services\PolicyAgent /v AssumeUDPEncapsulationContextOnSendRule /t REG_DWORD /d 0x2 /f
  ```

- For Windows XP only
  ```console
  REG ADD HKLM\SYSTEM\CurrentControlSet\Services\IPSec /v AssumeUDPEncapsulationContextOnSendRule /t REG_DWORD /d 0x2 /f
  ```

### OS X ###
1. Open System Preferences and go to the Network section.
1. Click the **+** button in the lower-left corner of the window.
1. Select **VPN** from the **Interface** drop-down menu.
1. Select **Cisco IPSec** from the **VPN Type** drop-down menu.
1. Enter anything you like for the **Service Name**.
1. Click **Create**.
1. Enter `Your VPN Server IP` for the **Server Address**.
1. Enter `Your VPN Username` for the **Account Name**.
1. Enter `Your VPN Password` for the **Password**.
1. Click the **Authentication Settings** button.
1. In the **Machine Authentication** section, select the **Shared Secret** radio button and enter `Your VPN IPsec PSK`.
1. Leave the **Group Name** field blank.
1. Click **OK**.
1. Check the **Show VPN status in menu bar** checkbox.
1. Click **Apply** to save the VPN connection information.

You can connect to the VPN using the VPN icon in the menu bar, or by selecting the VPN in the Network section of System Preferences and choosing **Connect**. You can verify that your traffic is being routed properly by <a href="https://encrypted.google.com/search?q=my+ip" target="_blank">looking up your IP address on Google</a>. It should say "Your public IP address is `Your VPN Server IP`".

### Android ###
1. Launch the **Settings** application.
1. Tap **More...** in the **Wireless & Networks** section.
1. Tap **VPN**.
1. Tap **Add VPN Profile** or the **+** icon at top-right of screen.
1. Enter anything you like in the **Name** field.
1. Select **IPSec Xauth PSK** in the **Type** drop-down menu.
1. Enter `Your VPN Server IP` in the **Server address** field.
1. Leave the **IPSec identifier** field blank.
1. Enter `Your VPN IPsec PSK` in the **IPSec pre-shared key** field.
1. Tap **Save**.
1. Tap the new VPN connection.
1. Enter `Your VPN Username` in the **Username** field.
1. Enter `Your VPN Password` in the **Password** field.
1. Check the **Save account information** checkbox.
1. Tap **Connect**.

**Note:** Android 6 (Marshmallow) users should edit `/etc/ipsec.conf` on the VPN server and append `,aes256-sha2_256` to both `ike=` and `phase2alg=` lines. Then add a new line `sha2-truncbug=yes` immediately after those. Indent lines with two spaces. When finished, run `service ipsec restart`. (<a href="https://libreswan.org/wiki/FAQ#Android_6.0_connection_comes_up_but_no_packet_flow" target="_blank">Reference</a>)

Once connected, you will see a VPN icon in the notification bar. You can verify that your traffic is being routed properly by <a href="https://encrypted.google.com/search?q=my+ip" target="_blank">looking up your IP address on Google</a>. It should say "Your public IP address is `Your VPN Server IP`".

### iOS ###
1. Go to Settings -> General -> VPN.
1. Tap **Add VPN Configuration...**.
1. Tap **Type**. Select **IPSec** and go back.
1. Tap **Description** and enter anything you like.
1. Tap **Server** and enter `Your VPN Server IP`.
1. Tap **Account** and enter `Your VPN Username`.
1. Tap **Password** and enter `Your VPN Password`.
1. Leave the **Group Name** field blank.
1. Tap **Secret** and enter `Your VPN IPsec PSK`.
1. Tap **Done**.
1. Slide the **VPN** switch ON.

Once connected, you will see a VPN icon in the status bar. You can verify that your traffic is being routed properly by <a href="https://encrypted.google.com/search?q=my+ip" target="_blank">looking up your IP address on Google</a>. It should say "Your public IP address is `Your VPN Server IP`".

## Credits

This document was adapted from the <a href="https://github.com/jlund/streisand" target="_blank">Streisand</a> project by Joshua Lund and contributors.

## License

Copyright (C) 2016 Lin Song   
Based on <a href="https://github.com/jlund/streisand/blob/master/playbooks/roles/l2tp-ipsec/templates/instructions.md.j2" target="_blank">the work of Joshua Lund</a> (Copyright 2014-2016)

This program is free software: you can redistribute it and/or modify it under the terms of the <a href="https://www.gnu.org/licenses/gpl.html" target="_blank">GNU General Public License</a> as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.