PPTP client works under Windows and doesn't work under Linux

senglory · 12-31-2021, 04:22 PM

I'm trying to use PPTP on my Slackware machine, the corresponding instruction was taken from - https://vexxhost.com/resources/tutor...ubuntu-debian/

Here's /etc/peers/khan002

Code:

pty "pptp VPN.VPN.VPN.VPN --nolaunchpppd"
name a
password a
remotename PPTP
require-mppe-128

Trying to run the PPTP client:

Code:

root@porteus:/etc/ppp/peers# pppd call khan002
Couldn't open the /dev/ppp device: No such file or directory
pppd: You need to create the /dev/ppp device node by
executing the following command as root:
   mknod /dev/ppp c 108 0

Ok, issuing mknod and again

Code:

root@porteus:/etc/ppp/peers# pppd call khan002

Silence in the answer. Meanwhile, at the client's log I see this:

Code:

Dec 28 19:41:39 porteus pppd[1938]: pppd 2.4.9 started by root, uid 0
Dec 28 19:41:40 porteus pptp[1939]: anon log[main:pptp.c:353]: The synchronous pptp option is NOT activated
Dec 28 19:41:40 porteus pppd[1938]: Using interface ppp0
Dec 28 19:41:40 porteus pppd[1938]: Connect: ppp0 <--> /dev/pts/3
Dec 28 19:41:40 porteus pptp[1951]: anon log[ctrlp_rep:pptp_ctrl.c:258]: Sent control packet type is 1 'Start-Control-Connection-Request'
Dec 28 19:41:40 porteus pptp[1951]: anon log[ctrlp_disp:pptp_ctrl.c:781]: Received Start Control Connection Reply
Dec 28 19:41:40 porteus pptp[1951]: anon log[ctrlp_disp:pptp_ctrl.c:815]: Client connection established.
Dec 28 19:41:40 porteus NetworkManager[629]: <info>  [1640979700.7934] manager: (ppp0): new Ppp device (/org/freedesktop/NetworkManager/Devices/3)
Dec 28 19:41:41 porteus pptp[1951]: anon log[ctrlp_rep:pptp_ctrl.c:258]: Sent control packet type is 7 'Outgoing-Call-Request'
Dec 28 19:41:41 porteus pptp[1951]: anon log[ctrlp_disp:pptp_ctrl.c:900]: Received Outgoing Call Reply.
Dec 28 19:41:41 porteus pptp[1951]: anon log[ctrlp_disp:pptp_ctrl.c:938]: Outgoing call established (call ID 34886, peer's call ID 34).
Dec 28 19:42:11 porteus pppd[1938]: Connection terminated.
Dec 28 19:42:11 porteus pppd[1938]: Modem hangup
Dec 28 19:42:11 porteus pppd[1938]: Exit.
Dec 28 19:42:11 porteus pptp[1951]: anon log[callmgr_main:pptp_callmgr.c:245]: Closing connection (unhandled)
Dec 28 19:42:11 porteus pptp[1951]: anon log[ctrlp_rep:pptp_ctrl.c:258]: Sent control packet type is 12 'Call-Clear-Request'
Dec 28 19:42:11 porteus pptp[1951]: anon log[call_callback:pptp_callmgr.c:84]: Closing connection (call state)
Dec 28 19:43:24 porteus dbus-daemon[1344]: [session uid=0 pid=1342] Activating service name='ca.desrt.dconf' requested by ':1.35' (uid=0 pid=1963 comm="mousepad messages ")
Dec 28 19:43:24 porteus dbus-daemon[1344]: [session uid=0 pid=1342] Successfully activated service 'ca.desrt.dconf'

Here's the matching piece of log at the server side:

Code:

Dec 28 22:58:30 pptpd[820]: CTRL: Client CLIENT.CLIENT.CLIENT.CLIENT control connection started
Dec 28 22:58:31 pptpd[820]: CTRL: Starting call (launching pppd, opening GRE)
Dec 28 22:58:31 pppd[821]: Plugin pptp.so loaded.
Dec 28 22:58:31 pppd[821]: PPTP plugin version 0.8.5 compiled for pppd-2.4.7
Dec 28 22:58:31 pppd[821]: pppd 2.4.7 started by admin, uid 0
Dec 28 22:58:31 pppd[821]: Using interface ppp10
Dec 28 22:58:31 pppd[821]: Connect: ppp10 <--> pptp (CLIENT.CLIENT.CLIENT.CLIENT)
Dec 28 22:59:01 pptpd[820]: CTRL: Reaping child PPP[821]
Dec 28 22:59:01 pptpd[820]: CTRL: Client pppd TERM sending
Dec 28 22:59:01 pptpd[820]: CTRL: Client pppd finish wait
Dec 28 22:59:01 pppd[821]: Terminating on signal 15
Dec 28 22:59:07 pppd[821]: Connection terminated.
Dec 28 22:59:07 pppd[821]: Modem hangup
Dec 28 22:59:07 pppd[821]: Exit.
Dec 28 22:59:07 pptpd[820]: CTRL: Client CLIENT.CLIENT.CLIENT.CLIENT control connection finished

Now the routing table has additional route

Code:

root@porteus:~# ip route
default via 10.0.2.2 dev eth0 proto dhcp metric 100
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15 metric 100
VPN.VPN.VPN.VPN via 10.0.2.2 dev eth0 src 10.0.2.15
127.0.0.0/8 dev lo scope link

Server - ASUS hardware router with PPTP turned on. Here're its settings https://ibb.co/qx3TjQ2

What did I do wrong and how to correct the settings?

techinfozone · 01-04-2022, 05:30 AM

Edit this file: /etc/modprobe.d/modules.conf, Find this value

alias char-major-108 ppp
And change it to this:

alias char-major-108 ppp_generic
if the file doesn't exist, create it with the file content.

Reboot afterwards

I hope this will work if it not then recheck the guide again.

senglory · 01-04-2022, 02:41 PM

Quote:

Originally Posted by techinfozone

Edit this file: /etc/modprobe.d/modules.conf, Find this value

alias char-major-108 ppp
And change it to this:

alias char-major-108 ppp_generic

Turned out this line is already in modules.conf

Quote:

Originally Posted by techinfozone

I hope this will work if it not then recheck the guide again.

Is this instruction for setting PPTP on VPN server? If yes the it's not my case because my server is a hardware router.

techinfozone · 01-05-2022, 08:59 AM

Quote:

Is this instruction for setting PPTP on VPN server? If yes the it's not my case because my server is a hardware router.

This is for server as well as VPN.
I thought It will help you but sorry not very useful to you.
Please send me link or answer when your issue will solved.

senglory · 01-05-2022, 09:12 AM

Quote:

Originally Posted by techinfozone

Is this instruction for setting PPTP on VPN server? If yes the it's not my case because my server is a hardware router.

Quote:

This is for server as well as VPN.

Not an option to do any changes at the server. And WinXP connects to it via PPTP w/o any issues and needs to tweak it.