ip_ecn.c revision 59391 
1/*
2 * Copyright (C) 1999 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $Id: ip_ecn.c,v 1.2 1999/07/30 12:17:15 itojun Exp $
30 * $FreeBSD: head/sys/netinet/ip_ecn.c 59391 2000-04-19 14:58:28Z phk $
31 */
32/*
33 * ECN consideration on tunnel ingress/egress operation.
34 * http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
35 */
36
37#include "opt_inet.h"
38#include "opt_inet6.h"
39
40#include <sys/param.h>
41#include <sys/systm.h>
42#include <sys/mbuf.h>
43#include <sys/errno.h>
44
45#ifdef INET
46#include <netinet/in.h>
47#include <netinet/in_systm.h>
48#include <netinet/ip.h>
49#endif
50
51#ifdef INET6
52#ifndef INET
53#include <netinet/in.h>
54#endif
55#include <netinet/ip6.h>
56#endif
57
58#include <netinet/ip_ecn.h>
59#ifdef INET6
60#include <netinet6/ip6_ecn.h>
61#endif
62
63/*
64 * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
65 * call it after you've done the default initialization/copy for the outer.
66 */
67void
68ip_ecn_ingress(mode, outer, inner)
69	int mode;
70	u_int8_t *outer;
71	u_int8_t *inner;
72{
73	if (!outer || !inner)
74		panic("NULL pointer passed to ip_ecn_ingress");
75
76	switch (mode) {
77	case ECN_ALLOWED:		/* ECN allowed */
78		*outer &= ~IPTOS_CE;
79		break;
80	case ECN_FORBIDDEN:		/* ECN forbidden */
81		*outer &= ~(IPTOS_ECT | IPTOS_CE);
82		break;
83	case ECN_NOCARE:	/* no consideration to ECN */
84		break;
85	}
86}
87
88/*
89 * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
90 * call it after you've done the default initialization/copy for the inner.
91 */
92void
93ip_ecn_egress(mode, outer, inner)
94	int mode;
95	u_int8_t *outer;
96	u_int8_t *inner;
97{
98	if (!outer || !inner)
99		panic("NULL pointer passed to ip_ecn_egress");
100
101	switch (mode) {
102	case ECN_ALLOWED:
103		if (*outer & IPTOS_CE)
104			*inner |= IPTOS_CE;
105		break;
106	case ECN_FORBIDDEN:		/* ECN forbidden */
107	case ECN_NOCARE:	/* no consideration to ECN */
108		break;
109	}
110}
111
112#ifdef INET6
113void
114ip6_ecn_ingress(mode, outer, inner)
115	int mode;
116	u_int32_t *outer;
117	u_int32_t *inner;
118{
119	u_int8_t outer8, inner8;
120
121	if (!outer || !inner)
122		panic("NULL pointer passed to ip6_ecn_ingress");
123
124	outer8 = (ntohl(*outer) >> 20) & 0xff;
125	inner8 = (ntohl(*inner) >> 20) & 0xff;
126	ip_ecn_ingress(mode, &outer8, &inner8);
127	*outer &= ~htonl(0xff << 20);
128	*outer |= htonl((u_int32_t)outer8 << 20);
129}
130
131void
132ip6_ecn_egress(mode, outer, inner)
133	int mode;
134	u_int32_t *outer;
135	u_int32_t *inner;
136{
137	u_int8_t outer8, inner8;
138
139	if (!outer || !inner)
140		panic("NULL pointer passed to ip6_ecn_egress");
141
142	outer8 = (ntohl(*outer) >> 20) & 0xff;
143	inner8 = (ntohl(*inner) >> 20) & 0xff;
144	ip_ecn_egress(mode, &outer8, &inner8);
145	*inner &= ~htonl(0xff << 20);
146	*inner |= htonl((u_int32_t)inner8 << 20);
147}
148#endif
149