[Openswan dev] pfkey_sock in spi.c

[mds]

Hello!
In spi.c on line 1191 (in the main function) the following socket is 
created:
pfkey_sock = socket(PF_KEY, SOCK_RAW, PF_KEY_V2)

later in the main function a write to the socket is performed (line 1608):
write(pfkey_sock, pfkey_msg, pfkey_msg->sadb_msg_len * IPSEC_PFKEYv2_ALIGN)

I couldn't locate the code where the message that was sent by this command
is recieved.
I would apreciate a short explanation of this mechanism very much.

Thanks for your time.
   Marco

PS:
I found a file documenting what files end up in kernel & user space in
openswanDir/linux/README.openswan-2. The problem there was that
that file is outdated (last update in 2003). The ipsec_netlink.c file is 
listed
in that readme - as an example - but ipsec_netlink.c does not exist in the
current version of Openswan.
Is it alright to assume that only code located in ./linux/net end up in
kernel space?