From 8434f10fbf81a15231b23373543e3c9234321166 Mon Sep 17 00:00:00 2001
From: dlg <dlg@openbsd.org>
Date: Sat, 20 Feb 2021 04:55:52 +0000
Subject: [PATCH] add p2p_input, like ether_input but for l3 tunnel interfaces.

the l3 protocol input to push the packet is based on a value in
m->m_pkthdr.ph_family, which tunnel drivers should set before calling
if_vinput.

add p2p_bpf_mtap to call bpf_mtap_af also using m->m_pkthdr.ph_family.
---
 sys/net/if.c     | 42 +++++++++++++++++++++++++++++++++++++++++-
 sys/net/if_var.h |  4 +++-
 2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/sys/net/if.c b/sys/net/if.c
index 9377bda5b44..3e0ce1643a6 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.631 2021/02/20 04:37:26 dlg Exp $	*/
+/*	$OpenBSD: if.c,v 1.632 2021/02/20 04:55:52 dlg Exp $	*/
 /*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/
 
 /*
@@ -853,6 +853,10 @@ if_vinput(struct ifnet *ifp, struct mbuf *m)
 	counters_pkt(ifp->if_counters,
 	    ifc_ipackets, ifc_ibytes, m->m_pkthdr.len);
 
+#if NPF > 0
+	pf_pkt_addr_changed(m);
+#endif
+
 #if NBPFILTER > 0
 	if_bpf = ifp->if_bpf;
 	if (if_bpf) {
@@ -1501,6 +1505,42 @@ p2p_rtrequest(struct ifnet *ifp, int req, struct rtentry *rt)
 	}
 }
 
+int
+p2p_bpf_mtap(caddr_t if_bpf, const struct mbuf *m, u_int dir)
+{
+#if NBPFILTER > 0
+	return (bpf_mtap_af(if_bpf, m->m_pkthdr.ph_family, m, dir));
+#else
+	return (0);
+#endif
+}
+
+void
+p2p_input(struct ifnet *ifp, struct mbuf *m)
+{
+	void (*input)(struct ifnet *, struct mbuf *);
+
+	switch (m->m_pkthdr.ph_family) {
+	case AF_INET:
+		input = ipv4_input;
+		break;
+#ifdef INET6
+	case AF_INET6:
+		input = ipv6_input;
+		break;
+#endif
+#ifdef MPLS
+	case AF_MPLS:
+		input = mpls_input;
+		break;
+#endif
+	default:
+		m_freem(m);
+		return;
+	}
+
+	(*input)(ifp, m);
+}
 
 /*
  * Bring down all interfaces
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 26c08284f0d..400afd319b0 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_var.h,v 1.113 2021/02/20 04:35:41 dlg Exp $	*/
+/*	$OpenBSD: if_var.h,v 1.114 2021/02/20 04:55:52 dlg Exp $	*/
 /*	$NetBSD: if.h,v 1.23 1996/05/07 02:40:27 thorpej Exp $	*/
 
 /*
@@ -327,6 +327,8 @@ int	if_input_local(struct ifnet *, struct mbuf *, sa_family_t);
 int	if_output_local(struct ifnet *, struct mbuf *, sa_family_t);
 void	if_rtrequest_dummy(struct ifnet *, int, struct rtentry *);
 void	p2p_rtrequest(struct ifnet *, int, struct rtentry *);
+void	p2p_input(struct ifnet *, struct mbuf *);
+int	p2p_bpf_mtap(caddr_t, const struct mbuf *, u_int);
 
 struct	ifaddr *ifa_ifwithaddr(struct sockaddr *, u_int);
 struct	ifaddr *ifa_ifwithdstaddr(struct sockaddr *, u_int);
-- 
2.20.1