nps-install

Convenient install scripts for ehang-io / nps, an intranet penetration proxy server.

Step 1: Setup NPS Server

Download and install the nps server at a virtual machine with a fixed IP address.

• default web interface will be served at port 8080.
• default client connection port at server side is 8024.

Step 2: Setup Clients

2.1: Create client entry in server configuration

• Create a new client on the web interface. Just fill in the remarks input box should be suffice. vkey will be automatically generated.
• Note down the generated vkey for the next step.

2.2: Install client on client machine

At this point, you should have your server running with a fixed ip address and a port number, and obtained a new vkey for this new client machine.

Run the following command to install the nps client on the client machine

python3 client_install.py --server SERVER_IP_ADDRESS --port SERVER_PORT --vkey CLIENT_VKEY

• --server and --vkey arguments are always required.
• --port is optional and default to 8024 if not specified.

Successful installation will be reflected on the web interface as a new online client.

If not, check if the port for connection client and server (8024) at the server side is open for traffic.

sudo ufw allow 8024
sudo ufw show added
sudo ufw enable

2.3 Setup penetration service

At this step, the port numbers may be slightly confusing, so take a breath. For example, we want to expose a client's SSH service to the public network. We have the following steps:

1. Make sure the SSH service is up and running in the client machine. The default port for ssh is 22, but you may specify it to be otherwise.
2. For SSH service, we will use a TCP connection between the client machine and the nps server. Hence, we go to the web interface of nps, under TCP tab, we click the +Add button.
   • Client ID can be found in the client tab, it is an auto-generated integer.
   • Server Port will be a new unoccupied port on the server that you intent to allocate it to this client's service.
   • Target (IP:Port) will be the address of the client service at the client's subnet. For example, for default ssh service, it will be at localhost:22.
   • click Add button to save.
3. Important: Make sure that on the server machine, firewall is configured appropriately to allow two-way traffic on the new Server Port mentioned above.
4. Once all is done, test the connection at AAAAAAA:BBBB where AAAAAAA is the ip address of the nps server and BBBB is the Server Port specified above.

Congrats, that's all.