Hello,

I have a Debian (sid) server with pptp installed. Everything works great, but I would like to only allow some users to connect from a specific IP address.

Current /etc/ppp/chap-secrets
What I would like:
I don't want to use a firewall, as I want some users to be able to connect from different IP addresses than others.

How can I do this? Is this possible?

Thanks!

I don't think that's possible. AFAIK, there are only four fields in /etc/ppp/chap-secrets, and you can only specify the IP address that is to be given to the PPP interface of a specific user.

However, if you're willing to switch to using RADIUS authentication instead, you can create a Network Access Policy that includes specifying valid client addresses for certain users.

Allow me to issue my standard warning for all PPTP-related questions: PPTP is fundamentally broken and offers little to no security. An attacker sniffing the network traffic (say, on a public wireless LAN) should be able to obtain a PPTP user's login credentials in less than 48 hours.

You should switch to another VPN protocol as soon as possible.

1 members found this post helpful.

Thanks for your answer. Too bad that it isn't possible without installing other software.

I know that PPTP is not secure, but I have many clients and I can't generate certificates for all of them (if I use OpenVPN).

//EDIT
I decided to install OpenVPN. Thanks.