We have an endian firewall (community, 2.4.0) as gateway, which is already serving as OpenVPN and IPSec endpoint (net-to-net). And we have many Android phones (most of them running Android 2.2 FroYo).
I'm currently trying to set up a VPN connection between the Android phones and the endian firewall. Thus the option would be OpenVPN or IPSec. For Android there is no "official" OpenVPN application. The ones available require root access, custom kernel modules for tun etc. That leaves IPSec as an option, as it's supported by Android.
I tried setting up an IPSec tunnel with PSK for testing on endian, but the phones keeps asking for username and password (PSK is set on the phone), which I don't know how to configure on endian. The only option available on endian is for OpenVPN users. If PSK tunnels work, I want to switch to PKI authentication with certificates, but I can't import the endian root key to Android as it is in PEM-format instead of p12.
How can I get IPSec running on endian firewall and android?