From 33a8a5933b4760fb36453ac4e7f16dcca01e6499 Mon Sep 17 00:00:00 2001
From: hwr <hwr@NetBSD.org>
Date: Mon, 3 May 1999 21:14:47 +0000
Subject: [PATCH] Drop packets, that have a Class-D address as source address.
 Implements the first half of PR 7003.

---
 sys/netinet/ip_input.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index 4f933a948648..45187ac521fe 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ip_input.c,v 1.84 1999/04/07 05:34:32 proff Exp $	*/
+/*	$NetBSD: ip_input.c,v 1.85 1999/05/03 21:14:47 hwr Exp $	*/
 
 /*-
  * Copyright (c) 1998 The NetBSD Foundation, Inc.
@@ -340,6 +340,15 @@ next:
 		}
 		ip = mtod(m, struct ip *);
 	}
+	/*
+	 * we drop packets that have a multicast address as source
+	 * as wanted by rfc 1112
+	 */
+	if (IN_MULTICAST(ip->ip_src.s_addr)) {
+		ipstat.ips_odropped++;
+		goto bad;
+	}
+
 	if (in_cksum(m, hlen) != 0) {
 		ipstat.ips_badsum++;
 		goto bad;