Strongswan to Cisco ASA with multiple right subnet

Solution 1:

The answer is simple, Cisco ASAs don't support multiple traffic selectors per CHILD_SA. So you have to negotiate individual CHILD_SAs for each combination of local and remote subnet you want to tunnel. That is, something like:

conn host2
    ...
    rightsubnet=192.168.1.0/24
    ...

conn host2-2
    also=host2
    rightsubnet=192.168.2.0/24

conn host2-3
    also=host2
    rightsubnet=192.168.3.0/24