[Openswan Users] Interop FC2:openswan<->RH:freeswan

[Clive A Stubbings]

I have a gateway, running 'old' superfreeswan on a RH box with a 2.4
kernel. Its fine. Road warrior works with x509 and NAT traversal to
freeswan and various windows tools.

I've just upgraded a linux laptop to Fedora Core 2 and openswan. (ie a 
2.6 series kernel).

I can establish a tunnel from the FC2 system to the old gateway.

But traffic gets dropped at the gateway with the error

Jul 13 11:05:53 xxxx kernel: klips_error:ipsec_rcv: got packet with content
	length = 118 from xxx.xxx.xxx.xxx -- should be on 4 octet boundary, packet dropped

This was a normal ping. If I change the ping packet size, it still
always generates a similar error - ie there is something systematically
making the size wrong.

Traffic the other way - ie gateway->laptop looks OK.

The laptop ipsec config is 'derived' from my old superfreeswan one.

Basically its..

version 2.0

config setup
	interfaces="ipsec0=eth0"
	uniqueids=ye
	overridemtu=1000
	nat_traversal=ye
	disable_port_floating=yes

conn %default
	keyingtries=0
	authby=rsasig
	auth=esp
	leftrsasigkey=%cert

conn roam
	leftid="C=.... etc"
	left=xx.xx.xx.xx
	leftsubnet=xx.xx.xx.xx/xx
	right=xx.xx.xx.xx
	rightnexthop=xx.xx.xx.xx
	rightcert=acert.pem
	pfs = yes
	auto=add


#Disable Opportunistic Encryption
include /etc/ipsec.d/examples/no_oe.conf


I tried without the interfaces line - that seens redundant now
I added the auth=esp to see if that would help, but it didn't

Any ideas?

Cheers
Clive