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, 2 insertions, 2 deletions

diff --git a/sys/netinet/raw_ip.c b/sys/netinet/raw_ip.c
index 8e02e41..632e00a 100644
--- a/sys/netinet/raw_ip.c
+++ b/sys/netinet/raw_ip.c
@@ -161,7 +161,7 @@ raw_append(struct inpcb *last, struct ip *ip, struct mbuf *n)
 	}
 #endif /*FAST_IPSEC*/
 #ifdef MAC
-	if (!policyfail && mac_check_socket_deliver(last->inp_socket, n) != 0)
+	if (!policyfail && mac_check_inpcb_deliver(last, n) != 0)
 		policyfail = 1;
 #endif
 	if (!policyfail) {
@@ -840,5 +840,5 @@ struct pr_usrreqs rip_usrreqs = {
 	pru_connect2_notsupp, in_control, rip_detach, rip_disconnect,
 	pru_listen_notsupp, rip_peeraddr, pru_rcvd_notsupp,
 	pru_rcvoob_notsupp, rip_send, pru_sense_null, rip_shutdown,
-	rip_sockaddr, sosend, soreceive, sopoll
+	rip_sockaddr, sosend, soreceive, sopoll, in_pcbsosetlabel
 };