Re: secmark=XXX mapping
One item to note: xt_SECMARK.c is presently using selinux-specific
interfaces for mapping the security context string to a sid originally,
as well as to check permissions, manage refcounts, etc. So if you use
the LSM hooks for mapping the secid back to a context, there will be an
inconsistency in the interface. Likely they should all be LSM hooks and
both include/linux/selinux.h and security/selinux/exports.c should go
away.
I found a way to alter the iptables source to get that information - see
my own thread on the netfilter mailing list here -
http://www.spinics.net/lists/netfilter/msg49094.html
Whether the devs responsible for iptables/netfilter would agree to make
these changes I am not sure - I patched my own iptables and it works!