From f47663ad1ab2e2faf61e4f34cc48ad4381881c8f Mon Sep 17 00:00:00 2001
From: mpi <mpi@openbsd.org>
Date: Tue, 23 Jun 2015 13:20:17 +0000
Subject: [PATCH] Pass a "struct ifnet *" instead of a "struct arpcom *" to
 arpresolve().

Most of the ARP layer already take an ifp pointer and this makes clear
wich chunks of code are messing with ac_enaddr.

Note that our Ethernet code assume that these pointer are interchangeable
since the first element of the "struct arpcom" is a "struct ifnet".
---
 sys/net/if_ethersubr.c |  6 +++---
 sys/netinet/if_ether.c | 13 +++++++------
 sys/netinet/if_ether.h |  4 ++--
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index 94d7370a57f..2b77da1998b 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ethersubr.c,v 1.206 2015/06/23 09:42:23 mpi Exp $	*/
+/*	$OpenBSD: if_ethersubr.c,v 1.207 2015/06/23 13:20:17 mpi Exp $	*/
 /*	$NetBSD: if_ethersubr.c,v 1.19 1996/05/07 02:40:30 thorpej Exp $	*/
 
 /*
@@ -197,7 +197,7 @@ ether_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 
 	switch (dst->sa_family) {
 	case AF_INET:
-		error = arpresolve(ac, rt, m, dst, edst);
+		error = arpresolve(ifp, rt, m, dst, edst);
 		if (error)
 			return (error == EAGAIN ? 0 : error);
 		/* If broadcasting on a simplex interface, loopback a copy */
@@ -233,7 +233,7 @@ ether_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 				    sizeof(edst));
 				break;
 			case AF_INET:
-				error = arpresolve(ac, rt, m, dst, edst);
+				error = arpresolve(ifp, rt, m, dst, edst);
 				if (error)
 					return (error == EAGAIN ? 0 : error);
 				break;
diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index 9209706131d..9f133241417 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ether.c,v 1.155 2015/06/16 11:09:40 mpi Exp $	*/
+/*	$OpenBSD: if_ether.c,v 1.156 2015/06/23 13:20:17 mpi Exp $	*/
 /*	$NetBSD: if_ether.c,v 1.31 1996/05/11 12:59:58 mycroft Exp $	*/
 
 /*
@@ -326,9 +326,10 @@ arprequest(struct ifnet *ifp, u_int32_t *sip, u_int32_t *tip, u_int8_t *enaddr)
  * Any other return value indicates an error.
  */
 int
-arpresolve(struct arpcom *ac, struct rtentry *rt0, struct mbuf *m,
+arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
     struct sockaddr *dst, u_char *desten)
 {
+	struct arpcom *ac = (struct arpcom *)ifp;
 	struct llinfo_arp *la;
 	struct sockaddr_dl *sdl;
 	struct rtentry *rt = NULL;
@@ -346,7 +347,7 @@ arpresolve(struct arpcom *ac, struct rtentry *rt0, struct mbuf *m,
 	}
 
 	if (rt0 != NULL) {
-		error = rt_checkgate(&ac->ac_if, rt0, dst,
+		error = rt_checkgate(ifp, rt0, dst,
 		    m->m_pkthdr.ph_rtableid, &rt);
 		if (error) {
 			m_freem(m);
@@ -369,7 +370,7 @@ arpresolve(struct arpcom *ac, struct rtentry *rt0, struct mbuf *m,
 				&satosin(dst)->sin_addr, addr, sizeof(addr)));
 	} else {
 		if ((la = arplookup(satosin(dst)->sin_addr.s_addr, 1, 0,
-		    ac->ac_if.if_rdomain)) != NULL)
+		    ifp->if_rdomain)) != NULL)
 			rt = la->la_rt;
 		else
 			log(LOG_DEBUG,
@@ -398,7 +399,7 @@ arpresolve(struct arpcom *ac, struct rtentry *rt0, struct mbuf *m,
 		memcpy(desten, LLADDR(sdl), sdl->sdl_alen);
 		return (0);
 	}
-	if (((struct ifnet *)ac)->if_flags & IFF_NOARP) {
+	if (ifp->if_flags & IFF_NOARP) {
 		m_freem(m);
 		return (EINVAL);
 	}
@@ -440,7 +441,7 @@ arpresolve(struct arpcom *ac, struct rtentry *rt0, struct mbuf *m,
 		if (la->la_asked == 0 || rt->rt_expire != time_second) {
 			rt->rt_expire = time_second;
 			if (la->la_asked++ < arp_maxtries)
-				arprequest(&ac->ac_if,
+				arprequest(ifp,
 				    &satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr,
 				    &satosin(dst)->sin_addr.s_addr,
 #if NCARP > 0
diff --git a/sys/netinet/if_ether.h b/sys/netinet/if_ether.h
index aa7394da822..5c544f93b75 100644
--- a/sys/netinet/if_ether.h
+++ b/sys/netinet/if_ether.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ether.h,v 1.56 2015/04/10 13:58:20 dlg Exp $	*/
+/*	$OpenBSD: if_ether.h,v 1.57 2015/06/23 13:20:17 mpi Exp $	*/
 /*	$NetBSD: if_ether.h,v 1.22 1996/05/11 13:00:00 mycroft Exp $	*/
 
 /*
@@ -192,7 +192,7 @@ extern struct niqueue arpintrq;
 
 void	arpwhohas(struct arpcom *, struct in_addr *);
 void	arpintr(void);
-int	arpresolve(struct arpcom *,
+int	arpresolve(struct ifnet *,
 	    struct rtentry *, struct mbuf *, struct sockaddr *, u_char *);
 void	arp_ifinit(struct arpcom *, struct ifaddr *);
 void	arp_rtrequest(int, struct rtentry *);
-- 
2.20.1