Do not perform arp send/resolve on an interface marked NOARP.

PR: 25006
MFC after: 2 weeks

4 files changed, 18 insertions, 6 deletions

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index f475f91..5b646b8 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -542,6 +542,11 @@ ether_demux(ifp, eh, m)
 		break;
 
 	case ETHERTYPE_ARP:
+		if (ifp->if_flags & IFF_NOARP) {
+			/* Discard packet if ARP is disabled on interface */
+			m_freem(m);
+			return;
+		}
 		schednetisr(NETISR_ARP);
 		inq = &arpintrq;
 		break;
diff --git a/sys/net/if_fddisubr.c b/sys/net/if_fddisubr.c
index 734eeec..0fc8451 100644
--- a/sys/net/if_fddisubr.c
+++ b/sys/net/if_fddisubr.c
@@ -443,14 +443,11 @@ fddi_input(ifp, fh, m)
 			break;
 
 		case ETHERTYPE_ARP:
-#if !defined(__bsdi__) || _BSDI_VERSION >= 199401
+			if (ifp->if_flags & IFF_NOARP)
+				goto dropanyway;
 			schednetisr(NETISR_ARP);
 			inq = &arpintrq;
 			break;
-#else
-			arpinput((struct arpcom *)ifp, m);
-			return;
-#endif
 #endif
 #ifdef INET6
 		case ETHERTYPE_IPV6:
diff --git a/sys/net/if_iso88025subr.c b/sys/net/if_iso88025subr.c
index a5538e0..2fd7747 100644
--- a/sys/net/if_iso88025subr.c
+++ b/sys/net/if_iso88025subr.c
@@ -473,6 +473,8 @@ iso88025_input(ifp, th, m)
 			break;
 
 		case ETHERTYPE_ARP:
+			if (ifp->if_flags & IFF_NOARP)
+				goto dropanyway;
 			schednetisr(NETISR_ARP);
 			inq = &arpintrq;
 			break;
diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index de5d906..8c8f01f 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -368,7 +368,7 @@ arpresolve(ac, rt, m, dst, desten, rt0)
 	register u_char *desten;
 	struct rtentry *rt0;
 {
-	register struct llinfo_arp *la = 0;
+	struct llinfo_arp *la = 0;
 	struct sockaddr_dl *sdl;
 
 	if (m->m_flags & M_BCAST) {	/* broadcast */
@@ -404,6 +404,14 @@ arpresolve(ac, rt, m, dst, desten, rt0)
 		return 1;
 	}
 	/*
+	 * If ARP is disabled on this interface, stop.
+	 * XXX
+	 * Probably should not allocate empty llinfo struct if we are
+	 * not going to be sending out an arp request.
+	 */
+	if (ac->ac_if.if_flags & IFF_NOARP)
+		return (0);
+	/*
 	 * There is an arptab entry, but no ethernet address
 	 * response yet.  Replace the held mbuf with this
 	 * latest one.