ip_ecn.c revision 55009 
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 55009 1999-12-22 19:13:38Z shin $
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/malloc.h>
43#include <sys/mbuf.h>
44#include <sys/errno.h>
45
46#ifdef INET
47#include <netinet/in.h>
48#include <netinet/in_systm.h>
49#include <netinet/ip.h>
50#endif
51
52#ifdef INET6
53#ifndef INET
54#include <netinet/in.h>
55#endif
56#include <netinet/ip6.h>
57#endif
58
59#include <netinet/ip_ecn.h>
60#ifdef INET6
61#include <netinet6/ip6_ecn.h>
62#endif
63
64/*
65 * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
66 * call it after you've done the default initialization/copy for the outer.
67 */
68void
69ip_ecn_ingress(mode, outer, inner)
70	int mode;
71	u_int8_t *outer;
72	u_int8_t *inner;
73{
74	if (!outer || !inner)
75		panic("NULL pointer passed to ip_ecn_ingress");
76
77	switch (mode) {
78	case ECN_ALLOWED:		/* ECN allowed */
79		*outer &= ~IPTOS_CE;
80		break;
81	case ECN_FORBIDDEN:		/* ECN forbidden */
82		*outer &= ~(IPTOS_ECT | IPTOS_CE);
83		break;
84	case ECN_NOCARE:	/* no consideration to ECN */
85		break;
86	}
87}
88
89/*
90 * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
91 * call it after you've done the default initialization/copy for the inner.
92 */
93void
94ip_ecn_egress(mode, outer, inner)
95	int mode;
96	u_int8_t *outer;
97	u_int8_t *inner;
98{
99	if (!outer || !inner)
100		panic("NULL pointer passed to ip_ecn_egress");
101
102	switch (mode) {
103	case ECN_ALLOWED:
104		if (*outer & IPTOS_CE)
105			*inner |= IPTOS_CE;
106		break;
107	case ECN_FORBIDDEN:		/* ECN forbidden */
108	case ECN_NOCARE:	/* no consideration to ECN */
109		break;
110	}
111}
112
113#ifdef INET6
114void
115ip6_ecn_ingress(mode, outer, inner)
116	int mode;
117	u_int32_t *outer;
118	u_int32_t *inner;
119{
120	u_int8_t outer8, inner8;
121
122	if (!outer || !inner)
123		panic("NULL pointer passed to ip6_ecn_ingress");
124
125	outer8 = (ntohl(*outer) >> 20) & 0xff;
126	inner8 = (ntohl(*inner) >> 20) & 0xff;
127	ip_ecn_ingress(mode, &outer8, &inner8);
128	*outer &= ~htonl(0xff << 20);
129	*outer |= htonl((u_int32_t)outer8 << 20);
130}
131
132void
133ip6_ecn_egress(mode, outer, inner)
134	int mode;
135	u_int32_t *outer;
136	u_int32_t *inner;
137{
138	u_int8_t outer8, inner8;
139
140	if (!outer || !inner)
141		panic("NULL pointer passed to ip6_ecn_egress");
142
143	outer8 = (ntohl(*outer) >> 20) & 0xff;
144	inner8 = (ntohl(*inner) >> 20) & 0xff;
145	ip_ecn_egress(mode, &outer8, &inner8);
146	*inner &= ~htonl(0xff << 20);
147	*inner |= htonl((u_int32_t)inner8 << 20);
148}
149#endif
150