xref: /freebsd/sys/netinet/ip_ecn.c (revision 23f282aa31e9b6fceacd449020e936e98d6f2298)
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  * $FreeBSD$
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  */
67 void
68 ip_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  */
92 void
93 ip_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
113 void
114 ip6_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 
131 void
132 ip6_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