I have a Netlink socket, subscribed to destroy events, by using bind
with NF_NETLINK_CONNTRACK_DESTROY
OR'd into the groups
parameter.
When looking through the nfnetlink_compat.h, though, I see that there're more flags than just NEW, UPDATE, and DESTROY - there's an EXP_XYZ variant for each flag as well:
#define NF_NETLINK_CONNTRACK_NEW 0x00000001
#define NF_NETLINK_CONNTRACK_UPDATE 0x00000002
#define NF_NETLINK_CONNTRACK_DESTROY 0x00000004
#define NF_NETLINK_CONNTRACK_EXP_NEW 0x00000008
#define NF_NETLINK_CONNTRACK_EXP_UPDATE 0x00000010
#define NF_NETLINK_CONNTRACK_EXP_DESTROY 0x00000020
I can't find the EXP_XYZ flags documented anywhere I've looked. Where can I find more information on these flags?