0. Prerequirement

• use SEED Ubuntu12.04 VM (32-bit) as your program's environment.
• successfully installed OpenSSL (in the VM above it should be OpenSSL 1.0.1) in you VM's Linux system

1. Compile and Clean-up

• Compile: type make
• Clean-up: type make clean

1.1 Security Implementation

1. Confidential: OpenSSL AES-256 CBC Mode
2. Integrity: OpenSSL HMAC-SHA256 Hashing Function
3. Authenticity: Set-up a local CA (related files are kept locally and not uploaded onto GitHub)

• Authenticated Encryption: use Encrypt-then-MAC method (as shown in slides)

2. Running Demo (Multiple VPN Tunnels)

2.1 Set up the tunnels

• Suppose you have 4 VMs running under the same local network(192.168.15.0/24), they are:
  1. "vm_0" (192.168.15.4)
  2. "jin511_" (192.168.15.5)
  3. "vm_3" (192.168.15.7)
  4. "vm_4" (192.168.15.8)
  • (Actually they are the real VMs which running on the Purdue Server mc20 under my user's subnet jin511)

1. In 192.168.15.4:/<path_2_working_dir>:
   • Type sudo su
   • Type sudo ./simpletun -i tun0 -s -d to start the server tun0 on 192.168.15.4 (virtual ip address 10.0.1.1)
   • Then in another window (or you can make the script above running in the backgroung), type bash first.sh to configure tun0's virtual ip address and the local route table
2. In 192.168.15.5:/<path_2_working_dir>:
   • Type sudo su
   • Type sudo ./simpletun -i tun0 -c 192.168.15.4 -d -v 10.0.2.1 to start the client tun0 on 192.168.15.5 (virtual ip address 10.0.2.1)
   • Then in another window (or you can make the script above running in the backgroung), type bash second.sh to configure tun0's virtual ip address and the local route table
3. In 192.168.15.7:/<path_2_working_dir>:
   • Type sudo su
   • Type sudo ./simpletun -i tun0 -c 192.168.15.4 -d -v 10.0.3.1 to start the client tun0 on 192.168.15.7 (virtual ip address 10.0.3.1)
   • Then in another window (or you can make the script above running in the backgroung), type bash third.sh to configure tun0's virtual ip address and the local route table
4. In 192.168.15.8:/<path_2_working_dir>:
   • Type sudo su
   • Type sudo ./simpletun -i tun0 -c 192.168.15.4 -d -v 10.0.4.1 to start the client tun0 on 192.168.15.8 (virtual ip address 10.0.4.1)
   • Then in another window (or you can make the script above running in the backgroung), type bash forth.sh to configure tun0's virtual ip address and the local route table

• Note that you can enter 0\n (change session key randomly) or 1\n (change session iv (for encryption)) on the client side in the same terminal of ./simpletun ....

2.2 Use the (bi-direction) tunnels

• Now, everything is done!
• You can manipulate any network operations between 10.0.1.1/24 and 10.0.2.1/24/10.0.3.1/24/10.0.4.1/24 (but not among last three)
• For example:
  • in "vm_0", type ssh cs528user@10.0.2.1/ssh cs528user@10.0.3.1/ssh cs528user@10.0.4.1
  • in "vm_3", type ping 10.0.1.1
  • in "jin511_", type ssh cs528user@10.0.1.1
  • ....
• Note that, all the ssh/ping/<other_network_operations> can be run simultaneously, with a normal functionality, since I already implemented a server which can build independent tunnels and multiple processes to handle requests from different addresses in parallel.