64Bit upgrade L2TP/IPsec Issue

Probably a stupid question, but what does your ipsec verify look like?

I've seen multiple reports of similar issues, and they're all caused by the fact that userspace is 32 bit, and the kernel is 64 bit, resulting in misalignment of data passed between them. This occurs with a lot of userspace applications which directly interface with the kernel, including IPsec (not L2TP specific) and OpenISCSI. The only available solutions are to go back to a 32 bit kernel, or deploy a 64 bit distro. Personally, I'd recommend taking the time to go through the latter process, as it's much more future proof.

I was curious :) I'm working on trying to get IPsec/L2TP setup on Ubuntu 14.04 with the latest kernel (or even any of the old ones). I'm running into

Checking your system to see if IPsec got installed and started correctly:
Version check and ipsec on-path                                 [OK]
Linux Openswan U2.6.38/K3.13.7-x86_64-linode38 (netkey)
Checking for IPsec support in kernel                            [OK]
 SAref kernel support                                           [N/A]
 NETKEY:  Testing XFRM related proc values                      [OK]
    [OK]
    [OK]
Checking that pluto is running                                  [OK]
 Pluto listening for IKE on udp 500                             [OK]
 Pluto listening for NAT-T on udp 4500                          [OK]
Checking your system to see if IPsec got installed and started correctly:
Version check and ipsec on-path                                 [OK]
Linux Openswan U2.6.38/K3.13.7-x86_64-linode38 (netkey)
Checking for IPsec support in kernel                            [OK]
 SAref kernel support                                           [N/A]
 NETKEY:  Testing XFRM related proc values                      [OK]
    [OK]
    [OK]
Checking that pluto is running                                  [OK]
 Pluto listening for IKE on udp 500                             [OK]
 Pluto listening for NAT-T on udp 4500                          [OK]
Two or more interfaces found, checking IP forwarding            [FAILED]
Checking NAT and MASQUERADEing                                  [OK]
Checking for 'ip' command                                       [OK]
Checking /bin/sh is not /bin/dash                               [WARNING]
Checking for 'iptables' command                                 [OK]
Opportunistic Encryption Support                                [DISABLED]
Checking NAT and MASQUERADEing                                  [OK]
Checking for 'ip' command                                       [OK]
Checking /bin/sh is not /bin/dash                               [WARNING]
Checking for 'iptables' command                                 [OK]
Opportunistic Encryption Support                                [DISABLED]

The problem being the "Two or more interfaces found, checking IP forwarding [FAILED]" test. I can't for the life of me figure out what's wrong. And scouring the web isn't producing any answers, only leading to reading the same question over and over from others who ended up stuck.

Ultimately, this is a you're stuck if you do, stuck if you don't scenario.

Rolled back to 12.04 LTS, which has an older package of OpenSwan… and bam:

Version check and ipsec on-path [OK]

Linux Openswan U2.6.37/K3.15.4-x86_64-linode45 (netkey)

Checking for IPsec support in kernel [OK]

SAref kernel support [N/A]

NETKEY: Testing XFRM related proc values [OK]

[OK]

[OK]

Checking that pluto is running [OK]

Pluto listening for IKE on udp 500 [OK]

Pluto listening for NAT-T on udp 4500 [OK]

Two or more interfaces found, checking IP forwarding [OK]

Checking NAT and MASQUERADEing [OK]

Checking for 'ip' command [OK]

Checking /bin/sh is not /bin/dash [WARNING]

Checking for 'iptables' command [OK]

Opportunistic Encryption Support [DISABLED]