Long story, short: I can't get a PPTP VPN tunnel established over cellular. Wifi just fine but apparently the wap.cingular APN that the iPhone uses just doesn't support this type of traffic. I tried setting it to isp.cingular but that doesn't work anymore.

So... I've been messing about with 2.0 since jailbreaking it, installing gcc and other compiling related things. After a little bit of tweaking, I got OpenVPN to compile fine. OpenVPN uses a standard udp connection to tunnel as opposed to a whole different IP encapsulation that PPTP uses. The brick wall I've run into is that OpenVPN requires a tun or tap interface in which to establish the tunnel.

This is provided on OS X by foo.tun/foo.tap kernel extensions which can be found at http://www-user.rhrk.uni-kl.de/~nissler/tuntap/. Compiling these is a bit tricker since it requires kernel headers and such. Does anyone have any experience in doing this? Is it even possible without the exact kernel source for the iPhone?

The jailbreak peeps crippled code signatures, so I have to figure there is somebody out there with the capability and know-how to do it. Help!

iPhone dev team is your best bet i guess. Try writing to them.

I am by means not an expert in vpn issues but I am extremely interested in an OpenVPN client for the iphone, too. Therefore, I made a little bit of research about it and it looks like it's highly complicated ...
Try to google for iPhone and OpenVPN, you'll find a lot of disencouraging information... Might be the Dev team are the best to talk to, but I guess they are totally packed with their 3G unlock.

Originally Posted by Durruti

I am by means not an expert in vpn issues but I am extremely interested in an OpenVPN client for the iphone, too. Therefore, I made a little bit of research about it and it looks like it's highly complicated ...
Try to google for iPhone and OpenVPN, you'll find a lot of disencouraging information... Might be the Dev team are the best to talk to, but I guess they are totally packed with their 3G unlock.

Most of what I found while Googling is that people don't understand the difference between OpenVPN and PPTP/IPSec. :) In any case, I'm not going to hold my breath too much since I'm sure the DevTeam is way too involved in the more prestigious 3G unlock. But if somebody with the knowledge would comment on just how difficult it is to get those tun/tap kext's compiled, that'd be at least throwing us a bone. :)

Originally Posted by MrPerfect

In any case, I'm not going to hold my breath too much since I'm sure the DevTeam is way too involved in the more prestigious 3G unlock.

I think the Dev Team consists of various specialists: baseband specialists who do the unlocks, main firmware specialists who might be able to help you (and who may not have been too busy since Pwnage has been released). Worth a try.

A very nice gentleman by the name of Michael IM'd me today and said he got tun/tap to compile. He provided me with the source and indeed, I was able to successfully compile. But it appears all is not that simple!

On a kextload after fiddling with some of the dependency options, it says it loads successfully, but alas, the module is not actually loaded as kextstat tells me.

I'll provide more details in a few hours, for now, I have a softball game to play!

So details...

Well, here are the kext's I'm using. As far as trying to load them, I've tried a few things but 'kextload -v 6 -b tun' yields:

kextload: adding repository /System/Library/Extensions
kextload: adding repository /System/Library/Extensions from a cache
kextload: added cached kernel extension /System/Library/Extensions/tap.kext
kextload: added cached kernel extension /System/Library/Extensions/tun.kext
kextload: added repository /System/Library/Extensions from cache
kextload: request to clear relationships while disabled; pending
kextload: clearing all version/dependency relationships among kernel extensions
kextload: calculating version relationships
kextload: looking up extension with identifier tun
kextload: sending 1 personality to the kernel

but it doesn't show up via kextstat. Digging deeper, I unloaded the PPTP.kext that was already loaded from using the standard VPN client. The unload indeed took as it disappeared from kextstat. However, the surprise is when I try to load the PPTP.kext with "kextload -v 6 -b pptp", it yielded the same:

kextload: adding repository /System/Library/Extensions
kextload: adding repository /System/Library/Extensions from a cache
kextload: added cached kernel extension /System/Library/Extensions/tap.kext
kextload: added cached kernel extension /System/Library/Extensions/tun.kext
kextload: added repository /System/Library/Extensions from cache
kextload: request to clear relationships while disabled; pending
kextload: clearing all version/dependency relationships among kernel extensions
kextload: calculating version relationships
kextload: looking up extension with identifier pptp
kextload: sending 1 personality to the kernel

but it doesn't load either! So either kextload is busted or the kernel doesn't use the same method for loading kext's as OS X does. I'm using the kext utilities from Cydia. Any ideas?

Thanks again to the gent that helped at least get the kexts compiled.

Did you find out any more and could you post how to compile source, etc?

I need tun.kext so i can tunnel the 3G connection to my laptop in a proper way over ssl without a proxy.

The source I used is at http://www.lqx.net/tuntap-iphone.source.tgz.

I haven't found any other info or success stories on loading kernel extensions on the iPhone though.

Hm, when i look at the tun makefile, it has includes in it that are not in place on my iphone. Can that be the cause of the problem

Code:

kextload: cannot resolve dependencies for kernel extension /System/Library/Extensions/tun.kext

?

Also it is not loading when it says

Code:

kextload: sending 1 personality to the kernel

, it should give a lot more lines after that and end with

Code:

kextload: /System/Library/Extensions/tun.kext loaded successfully

Tomorrow i am going on holidays, if not solved by then, i'll continue on this when i get home after that. We should be able to solve this.