xref: /freebsd/sys/netinet/ip_ecn.c (revision b601c69bdbe8755d26570261d7fd4c02ee4eff74)
1 /*	$FreeBSD$	*/
2 /*	$KAME: ip_ecn.c,v 1.7 2000/05/05 11:00:56 sumikawa Exp $	*/
3 
4 /*
5  * Copyright (C) 1999 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  */
33 /*
34  * ECN consideration on tunnel ingress/egress operation.
35  * http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
36  */
37 
38 #include "opt_inet.h"
39 #include "opt_inet6.h"
40 
41 #include <sys/param.h>
42 #include <sys/systm.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  */
68 void
69 ip_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  */
93 void
94 ip_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
114 void
115 ip6_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 
132 void
133 ip6_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