If you have GIT and Cogito installed, it's a single command line to get the #testing branch (Where new releases come from - 2.5.x):

cg-clone http://git.openswan.org/public/scm/openswan.git#testing openswan-2

To get the IKEv2 branch (under development, not completed yet) cg-clone http://git.openswan.org/public/scm/openswan.git#ikev2 openswan-2

Note: GIT commits to are pushed on the hour from the master repository, so if you see developer commits, you'll need until the top of the hour for them to become available publically.

See docs/HACKING/ for more info about our GIT respository.