new file mode 100644
--- /dev/null
+++ b/packages/net/bsd_tcpip/current/src/sys/netinet/ip_ecn.c
@@ -0,0 +1,154 @@
+//==========================================================================
+//
+//      src/sys/netinet/ip_ecn.c
+//
+//==========================================================================
+//####BSDCOPYRIGHTBEGIN####
+//
+// -------------------------------------------
+//
+// Portions of this software may have been derived from OpenBSD, 
+// FreeBSD or other sources, and are covered by the appropriate
+// copyright disclaimers included herein.
+//
+// Portions created by Red Hat are
+// Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+//
+// -------------------------------------------
+//
+//####BSDCOPYRIGHTEND####
+//==========================================================================
+
+/*	$KAME: ip_ecn.c,v 1.11 2001/05/03 16:09:29 itojun Exp $	*/
+
+/*
+ * Copyright (C) 1999 WIDE Project.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+/*
+ * ECN consideration on tunnel ingress/egress operation.
+ * http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
+ */
+
+#include <sys/param.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/errno.h>
+
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#ifdef INET6
+#include <netinet/ip6.h>
+#endif
+
+#include <netinet/ip_ecn.h>
+
+/*
+ * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
+ */
+void
+ip_ecn_ingress(mode, outer, inner)
+	int mode;
+	u_int8_t *outer;
+	const u_int8_t *inner;
+{
+	if (!outer || !inner)
+		panic("NULL pointer passed to ip_ecn_ingress");
+
+	*outer = *inner;
+	switch (mode) {
+	case ECN_ALLOWED:		/* ECN allowed */
+		*outer &= ~IPTOS_CE;
+		break;
+	case ECN_FORBIDDEN:		/* ECN forbidden */
+		*outer &= ~(IPTOS_ECT | IPTOS_CE);
+		break;
+	case ECN_NOCARE:	/* no consideration to ECN */
+		break;
+	}
+}
+
+/*
+ * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
+ */
+void
+ip_ecn_egress(mode, outer, inner)
+	int mode;
+	const u_int8_t *outer;
+	u_int8_t *inner;
+{
+	if (!outer || !inner)
+		panic("NULL pointer passed to ip_ecn_egress");
+
+	switch (mode) {
+	case ECN_ALLOWED:
+		if (*outer & IPTOS_CE)
+			*inner |= IPTOS_CE;
+		break;
+	case ECN_FORBIDDEN:		/* ECN forbidden */
+	case ECN_NOCARE:	/* no consideration to ECN */
+		break;
+	}
+}
+
+#ifdef INET6
+void
+ip6_ecn_ingress(mode, outer, inner)
+	int mode;
+	u_int32_t *outer;
+	const u_int32_t *inner;
+{
+	u_int8_t outer8, inner8;
+
+	if (!outer || !inner)
+		panic("NULL pointer passed to ip6_ecn_ingress");
+
+	inner8 = (ntohl(*inner) >> 20) & 0xff;
+	ip_ecn_ingress(mode, &outer8, &inner8);
+	*outer &= ~htonl(0xff << 20);
+	*outer |= htonl((u_int32_t)outer8 << 20);
+}
+
+void
+ip6_ecn_egress(mode, outer, inner)
+	int mode;
+	const u_int32_t *outer;
+	u_int32_t *inner;
+{
+	u_int8_t outer8, inner8;
+
+	if (!outer || !inner)
+		panic("NULL pointer passed to ip6_ecn_egress");
+
+	outer8 = (ntohl(*outer) >> 20) & 0xff;
+	ip_ecn_egress(mode, &outer8, &inner8);
+	*inner &= ~htonl(0xff << 20);
+	*inner |= htonl((u_int32_t)inner8 << 20);
+}
+#endif