Raspberry Pi [TUTORIAL] PPTP server (VPN)

[R-Pi] [TUTORIAL] PPTP server (VPN) - Printable Version

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[TUTORIAL] PPTP server (VPN) - slober - Oct 27, 2013

PPTP server

what is a PPTP server?

Security on a PPTP server

PPTP vs OpenVPN

PPTP Usage

PPTP on the rasp.

Enjoy

what is a PPTP server?
PPTP stands for Point to Point Tunneling Protocol it's a method for implementing virtual private networking

]Security on a PPTP server
PPTP has security flaws but it's easier to setup and is generally faster and better supported on mobile devices
the encryption used is 40, 56 of 128 bit MPPE Microsoft Protocol stands for Microsoft Point-to-Point Encryption. It uses the RSA RC4 encryption algorithm

Quote:Wikipedia:

PPTP has been the subject of many security analyses and serious security vulnerabilities have been found in the protocol. The known vulnerabilities relate to the underlying PPP authentication protocols used, the design of the MPPE protocol as well as the integration between MPPE and PPP authentication for session key establishment. PPTP is (as of Oct 2012) considered cryptographically broken and its use is no longer recommended by Microsoft.

so it can be cracked but it's still better then nothing right?
PPTP vs OpenVPN

PPTP

Advantages:
1.) Works better on Mobile Devices (PPTP & L2TP)
2.) Speed PPTP is usually faster because it has a weaker encryption key

Disadvantages:
1.) when a PPTP server can't connect with the client it drops the connection This will exposé your computer to the Internet off the VPN. For some people this is unacceptable
2.) Stability problems on DD-WRT firmware
3.) Fixed Ports

OpenVPN

Advantages:
1.) Works good on DD-WRT routers
2.) Stronger Encryption
3.) more stable
5.) Port Modification and Protocol Modification Ability

Disadvantages:
1.) Requires Software
2.) Some consider it complex
3.) slower (i could really tell the difference between PPTP and Open VPN on my pi)

PPTP Usage
it can do the same things as your VPN only a bit less secure so.. don't do stupid things PPTP can be cracked but it's great for accessing your home network, and your basic security needs everything is better then nothing

PPTP on the rasp.
Step 1
make sure you're pi is running and everything is nice and up-to-date
if not use the following commands

Code 
sudo raspi-config

for expanding your file system, overclocking,...

Code 
sudo apt-get update -y

sudo apt-get upgrade -y

for upating everything

Step 2

Code 
modprobe ppp-compress-18 && echo success

apt-get install pptpd -y

first line will test the MPPE support if it don't say success update your files
second line will install the PPTP server

Step 3

Code 
vi /etc/pptpd.conf

Code 
nano /etc/pptpd.conf

edit the pptpd.conf file with your fav. texteditor

At the end of the file uncomment the following lines. Replace RPI_IP with the IP of your Raspberry Pi. The remoteip param is for the addresses that will be handed out to VPN clients.

Code 
localip RPI_IP

remoteip 192.168.2.234-238,192.168.2.245

Make a backup file before you alter stuff
save your changes!

Step 4

Code 
nano /etc/ppp/pptpd-options

Code 
vi /etc/ppp/pptpd-options

let's edit the Options

Append the following to the end of the file. The ms-dns param is the IP of the internal DNS server. In most cases this will be the router.

Code 
ms-dns 192.168.1.1

noipx

mtu 1490

mru 1490

Make a backup file before you alter stuff
save your changes!

Step 5
Edit chap-secrets

Code 
vi /etc/ppp/chap-secrets

nano /etc/ppp/chap-secrets

this will make the login for the PPTP

Code 
LAYOUT:

username    *   password   *

Step 6
restart the server

Code 
service pptpd restart

final step
forward the adress 1723 in your router and your done ^^

Code 
netstat -ntlp

Code 
netstat -l

check if the pi is running it

Trouble shouting:
if the comands won't work try putting sudo before it

Enjoy
so enjoy it 👍 you now have you're ow raspberry PPTP server

Sources used:
Spoiler (Click to View)