Wierd issue on AC68U - 384_2 and 385

[Pradeep]

Hello all,

i am kind of new here - don't remember posting here but read some here and there in this forum. apologize in advance if i am posting something wrong!

i have an AC68U and seem to have a wierd issue and guess it's realated to some VPN... i have used PPTP VPN before on this device and it worked well in the past. i had a reset the router sometime back and didn't use VPN for sometime.

Yesterday i configured the VPN and tried to connect but it didn't seem to work - showed up Authentication error, so i looked into the logs and thats where i find this....

May 30 17:41:57 pptp[596]: Using interface ppp5
May 30 17:41:57 pptp[596]: Connect: ppp5 <--> pptp (139.59.24.191)
May 30 17:41:57 pptp[596]: MS-CHAP authentication failed:
May 30 17:41:57 pptp[596]: CHAP authentication failed
May 30 17:41:57 pptp[596]: Connection terminated.
May 30 17:42:09 pptp[596]: Using interface ppp5
May 30 17:42:09 pptp[596]: Connect: ppp5 <--> pptp (139.59.30.192)
May 30 17:42:09 pptp[596]: MS-CHAP authentication failed:
May 30 17:42:09 pptp[596]: CHAP authentication failed
May 30 17:42:10 pptp[596]: Connection terminated.
May 30 17:42:21 pptp[596]: Using interface ppp5
May 30 17:42:21 pptp[596]: Connect: ppp5 <--> pptp (139.59.17.96)
May 30 17:42:24 pptp[596]: MS-CHAP authentication failed:
May 30 17:42:24 pptp[596]: CHAP authentication failed
May 30 17:42:25 pptp[596]: Connection terminated.
May 30 17:42:36 pptp[596]: Using interface ppp5
May 30 17:42:36 pptp[596]: Connect: ppp5 <--> pptp (139.59.30.192)
May 30 17:42:37 pptp[596]: MS-CHAP authentication failed:
May 30 17:42:37 pptp[596]: CHAP authentication failed
May 30 17:42:37 pptp[596]: Connection terminated.

This seems to happen infintely and continues to show on the log for every couple of seconds.. i thought it was my VPN trying to connect again and then removed the configuration, but still the log doesn't stop...

i upgraded to 385 and performed a full reset, then tried to downgraded to 384_2. Then i thought it might be an issue with Merling firmware and then moved to ASUS official firmware... and still this continues.. the wierd thing is the IP of the PPTP connect seems to be changing somewhat randomly...

any thoughts on how to address this issue and to get the router connect to PPTP?

 

[eastavin]

Well my first reaction is don't use PPTP. The encryption was broken like decades ago. Its not secure by any stretch of ones imagination. Use OpenVPN.

 

[Pradeep]

Well my first reaction is don't use PPTP. The encryption was broken like decades ago. Its not secure by any stretch of ones imagination. Use OpenVPN.

I agree, but my ISP seems to be not very happy with OpenVPN connections and started blocking it.

 

[ColinTaylor]

Can you confirm you are talking about the router's VPN client and not the server. If you can't connect to your VPN service provider maybe you should check your configuration with them.

 

[Pradeep]

Can you confirm you are talking about the router's VPN client and not the server. If you can't connect to your VPN service provider maybe you should check your configuration with them.

it's the VPN Client and not the server. i have used this before on my router and able to use it on other devices - my phone, laptop at the moment - so makes me think something is wrong in the router... the weird thing is that the pptp connection seems to be looping and never ending even if there is no vpn configuration.. i have deleted all my vpn config's on the router.

 

[kfp]

Seems like you’re connecting to an endpoint hosted at DigitalOcean so the changing IP behaviour is normal.

Are you sure you are using the right credentials? Have you tried making a PPTP connection to it using another device like a phone or computer?

 

[eastavin]

I agree, but my ISP seems to be not very happy with OpenVPN connections and started blocking it.

Well there in lies another issue. I don't know what country you are in but if they are actually blocking OpenVPN then maybe its because they prefer to be able to see what your transmitting with the broken security of PPTP. If you are going to invest effort in getting something working I would recommend you invest your time on OPENVPN.

As we don't know your application end goal its hard to say exactly what to do. If OpenVPN is really being blocked I would suggest you try something even more secure not something with NO security like PPTP. I would forget about the router VPNs and use https://www.torproject.org/ software with some type of obfuscation turned on to connect your PC or https://guardianproject.info/apps/orbot/ for your smartphone directly to the destination you have in mind. I have had success at connecting out of places trying to block VPNs with Tor's bridges and obfuscation options. It might work for you too.

 

[Pradeep]

thanks @kfp for the finding on digitalocean.

tgabjs @eastavin. i wasn't too worried about the content, but what you say makes real sense.

i seem to have found the issues - it's with the username of my vpn provider. its rather long and i have always used a HTML hack to enter more than 64 characters which the router usually allows.

Jun 1 23:10:54 httpd: nvram_check fail: nvram vpnc_pppoe_username over length (67 > 64)

i wonder from where this restriction is being enforced? would there be a hack/config change which can help here?

 

[ColinTaylor]

i wonder from where this restriction is being enforced? would there be a hack/config change which can help here?

No. The new length restrictions are compiled into the firmware.

 

[Pradeep]

No. The new length restrictions are compiled into the firmware.

Thank Colin, just logged into to the VPN provider to see if there is an shorted username password that i can used and that worked!

thank you so much for your help.