[Openswan Users] Incorrect UDP checksum problem

[Juha Pietikäinen]

Hi,

my configuration is discribed in my earlier message:
http://lists.openswan.org/pipermail/users/2004-May/000717.html

IPsec SA is now established according to secure log, but I cannot make L2TP
connection because L2TP packets (Control Message - SCCRQ) are rejected due
to incorrect UDP checksums.

Ethereal shows that Windows XP client is sending UDP packets having
incorrect UDP checksums. L2TP packets are encapsulated inside these UDP
packets.

My SMC barricade ADSL-router supports only ESP tunnel mode and Windows XPs
native L2TP/IPsec client is using ESP transport mode with IPsec, which is
probably causing the problem.

Are there any good workarounds for solving the problem?

Is it possible to disable UDP checksum calculation for testing purposes from
Windows XP and Fedora Core 1?

I know that the problem isn't really Openswan specific, but this might be
the best place to get help.

My Openswan version is 2.1.2.


Regards

Juha Pietikäinen