protosw: separate pr_input and pr_ctlinput out of protosw

The protosw KPI historically has implemented two quite orthogonal
things: protocols that implement a certain kind of socket, and
protocols that are IPv4/IPv6 protocol.  These two things do not
make one-to-one correspondence. The pr_input and pr_ctlinput methods
were utilized only in IP protocols.  This strange duality required
IP protocols that doesn't have a socket to declare protosw, e.g.
carp(4).  On the other hand developers of socket protocols thought
that they need to define pr_input/pr_ctlinput always, which lead to
strange dead code, e.g. div_input() or sdp_ctlinput().

With this change pr_input and pr_ctlinput as part of protosw disappear
and IPv4/IPv6 get their private single level protocol switch table
ip_protox[] and ip6_protox[] respectively, pointing at array of
ipproto_input_t functions.  The pr_ctlinput that was used for
control input coming from the network (ICMP, ICMPv6) is now represented
by ip_ctlprotox[] and ip6_ctlprotox[].

ipproto_register() becomes the only official way to register in the
table.  Those protocols that were always static and unlikely anybody
is interested in making them loadable, are now registered by ip_init(),
ip6_init().  An IP protocol that considers itself unloadable shall
register itself within its own private SYSINIT().

Reviewed by:		tuexen, melifaro
Differential revision:	https://reviews.freebsd.org/D36157

1 files changed, 3 insertions, 1 deletions

diff --git a/sys/netipsec/ipsec_input.c b/sys/netipsec/ipsec_input.c
index 1548a87c844d..ca6c6592dfa4 100644
--- a/sys/netipsec/ipsec_input.c
+++ b/sys/netipsec/ipsec_input.c
@@ -573,6 +573,8 @@ ipsec6_ctlinput(int code, struct sockaddr *sa, void *v)
 	return (0);
 }
 
+extern ipproto_input_t	*ip6_protox[];
+
 /*
  * IPsec input callback, called by the transform callback. Takes care of
  * filtering and other sanity checks on the processed packet.
@@ -760,7 +762,7 @@ ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip,
 			error = EINVAL;
 			goto bad;
 		}
-		nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt);
+		nxt = ip6_protox[nxt](&m, &skip, nxt);
 	}
 	NET_EPOCH_EXIT(et);
 	key_freesav(&sav);