VPN with PPTP failing

koto...@gmail.com

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Aug 13, 2016, 6:22:16 AM8/13/16

to qubes-users

Hi,

I'm trying to setup a VPN connection with PPTP from sys-net (first tried with the ProxyVM but it also didn't work) without success.

Any help is welcome, here below the logs.
I also tried

$ sudo modprobe nf_conntrack_pptp

without success.

I'm using the fedora template.

Plugin /usr/lib64/pppd/2.4.7/nm-pptp-pppd-plugin.so loaded.
using channel 9
Using interface ppp0
Connect: ppp0 <--> /dev/pts/1
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xbdaa77d8> <pcomp> <accomp>]
LCP: timeout sending Config-Requests
Connection terminated.
Modem hangup
Script /sbin/pptp 91.233.116.223 --nolaunchpppd --loglevel 2 --logstring nm-pptp-service-5272 finished (pid 5281), status = 0x0

Andrew David Wong

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Aug 13, 2016, 6:34:28 AM8/13/16

to koto...@gmail.com, qubes-users

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

On 2016-08-13 03:22, koto...@gmail.com wrote:
> Hi,
>
> I'm trying to setup a VPN connection with PPTP from sys-net (first tried
> with the ProxyVM but it also didn't work) without success.
>
> Any help is welcome, here below the logs. I also tried
>
> $ sudo modprobe nf_conntrack_pptp
>
> without success.
>
> I'm using the fedora template.
>

> [...]
>

I'm afraid I don't have any specific help to offer, but you didn't mention
whether you've already had a look at our VPN documentation. In case you
weren't already aware of it, you mind find some useful information:

https://www.qubes-os.org/doc/vpn/

- --
Andrew David Wong (Axon)
Community Manager, Qubes OS
https://www.qubes-os.org
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Unman

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Aug 14, 2016, 7:14:06 PM8/14/16

to koto...@gmail.com, qubes-users

My guess is that you are blocking the connection from the VPN
server.
PPTP requires you to allow inbound GRE traffic.
If your server is at X.X.X.X, and the VPN client is attached to sys-net
then you want something like this on sys-net:

modprobe ip_conntrack_pptp
modprobe ip_nat_pptp
iptables -I FORWARD -p 47 -s X.X.X.X -J ACCEPT

See if that helps.

u

koto...@gmail.com

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Aug 15, 2016, 12:47:50 AM8/15/16

to qubes-users, koto...@gmail.com, un...@thirdeyesecurity.org

> modprobe ip_conntrack_pptp
> modprobe ip_nat_pptp
> iptables -I FORWARD -p 47 -s X.X.X.X -J ACCEPT
>

What setup do I need for a ProxyVM?

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