1/*
2 * Copyright (c) 2000,2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*
29 * Copyright (C) 1999 WIDE Project.
30 * All rights reserved.
31 *
32 * Redistribution and use in source and binary forms, with or without
33 * modification, are permitted provided that the following conditions
34 * are met:
35 * 1. Redistributions of source code must retain the above copyright
36 *    notice, this list of conditions and the following disclaimer.
37 * 2. Redistributions in binary form must reproduce the above copyright
38 *    notice, this list of conditions and the following disclaimer in the
39 *    documentation and/or other materials provided with the distribution.
40 * 3. Neither the name of the project nor the names of its contributors
41 *    may be used to endorse or promote products derived from this software
42 *    without specific prior written permission.
43 *
44 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
45 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
46 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
47 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
48 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
49 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
50 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
51 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
52 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
53 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
54 * SUCH DAMAGE.
55 *
56 */
57/*
58 * ECN consideration on tunnel ingress/egress operation.
59 * http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
60 */
61
62#include <sys/param.h>
63#include <sys/systm.h>
64#include <sys/malloc.h>
65#include <sys/mbuf.h>
66#include <sys/errno.h>
67
68#include <netinet/in.h>
69#include <netinet/in_systm.h>
70#include <netinet/ip.h>
71#if INET6
72#include <netinet/ip6.h>
73#endif
74
75#include <netinet/ip_ecn.h>
76#if INET6
77#include <netinet6/ip6_ecn.h>
78#endif
79
80/*
81 * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
82 */
83void
84ip_ecn_ingress(mode, outer, inner)
85	int mode;
86	u_int8_t *outer;
87	const u_int8_t *inner;
88{
89	if (!outer || !inner)
90		panic("NULL pointer passed to ip_ecn_ingress");
91
92	*outer = *inner;
93	switch (mode) {
94	case ECN_ALLOWED:		/* ECN allowed */
95		*outer &= ~IPTOS_CE;
96		break;
97	case ECN_FORBIDDEN:		/* ECN forbidden */
98		*outer &= ~(IPTOS_ECT | IPTOS_CE);
99		break;
100	case ECN_NOCARE:	/* no consideration to ECN */
101		break;
102	}
103}
104
105/*
106 * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
107 */
108void
109ip_ecn_egress(mode, outer, inner)
110	int mode;
111	const u_int8_t *outer;
112	u_int8_t *inner;
113{
114	if (!outer || !inner)
115		panic("NULL pointer passed to ip_ecn_egress");
116
117	switch (mode) {
118	case ECN_ALLOWED:
119		if (*outer & IPTOS_CE)
120			*inner |= IPTOS_CE;
121		break;
122	case ECN_FORBIDDEN:		/* ECN forbidden */
123	case ECN_NOCARE:	/* no consideration to ECN */
124		break;
125	}
126}
127
128#if INET6
129void
130ip6_ecn_ingress(mode, outer, inner)
131	int mode;
132	u_int32_t *outer;
133	const u_int32_t *inner;
134{
135	u_int8_t outer8, inner8;
136
137	if (!outer || !inner)
138		panic("NULL pointer passed to ip6_ecn_ingress");
139
140	inner8 = (ntohl(*inner) >> 20) & 0xff;
141	ip_ecn_ingress(mode, &outer8, &inner8);
142	*outer &= ~htonl(0xff << 20);
143	*outer |= htonl((u_int32_t)outer8 << 20);
144}
145
146void
147ip6_ecn_egress(mode, outer, inner)
148	int mode;
149	const u_int32_t *outer;
150	u_int32_t *inner;
151{
152	u_int8_t outer8, inner8;
153
154	if (!outer || !inner)
155		panic("NULL pointer passed to ip6_ecn_egress");
156
157	outer8 = (ntohl(*outer) >> 20) & 0xff;
158	inner8 = (ntohl(*inner) >> 20) & 0xff;
159	ip_ecn_egress(mode, &outer8, &inner8);
160	*inner &= ~htonl(0xff << 20);
161	*inner |= htonl((u_int32_t)inner8 << 20);
162}
163#endif
164