Introduce a MAC label reference in 'struct inpcb', which caches

the   MAC label referenced from 'struct socket' in the IPv4 and
IPv6-based protocols.  This permits MAC labels to be checked during
network delivery operations without dereferencing inp->inp_socket
to get to so->so_label, which will eventually avoid our having to
grab the socket lock during delivery at the network layer.

This change introduces 'struct inpcb' as a labeled object to the
MAC Framework, along with the normal circus of entry points:
initialization, creation from socket, destruction, as well as a
delivery access control check.

For most policies, the inpcb label will simply be a cache of the
socket label, so a new protocol switch method is introduced,
pr_sosetlabel() to notify protocols that the socket layer label
has been updated so that the cache can be updated while holding
appropriate locks.  Most protocols implement this using
pru_sosetlabel_null(), but IPv4/IPv6 protocols using inpcbs use
the the worker function in_pcbsosetlabel(), which calls into the
MAC Framework to perform a cache update.

Biba, LOMAC, and MLS implement these entry points, as do the stub
policy, and test policy.

Reviewed by:	sam, bms
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/netinet/ip_divert.c b/sys/netinet/ip_divert.c
index 7e939e3..172021b 100644
--- a/sys/netinet/ip_divert.c
+++ b/sys/netinet/ip_divert.c
@@ -652,5 +652,5 @@ struct pr_usrreqs div_usrreqs = {
 	pru_connect_notsupp, pru_connect2_notsupp, in_control, div_detach,
 	div_disconnect, pru_listen_notsupp, div_peeraddr, pru_rcvd_notsupp,
 	pru_rcvoob_notsupp, div_send, pru_sense_null, div_shutdown,
-	div_sockaddr, sosend, soreceive, sopoll
+	div_sockaddr, sosend, soreceive, sopoll, in_pcbsosetlabel
 };