1 /* $NetBSD: ip_ecn.c,v 1.17 2017/12/09 08:03:07 pgoyette Exp $ */
2 /* $KAME: ip_ecn.c,v 1.11 2001/05/03 16:09:29 itojun 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 <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: ip_ecn.c,v 1.17 2017/12/09 08:03:07 pgoyette Exp $");
40
41 #ifdef _KERNEL_OPT
42 #include "opt_inet.h"
43 #endif
44
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/malloc.h>
48 #include <sys/mbuf.h>
49 #include <sys/errno.h>
50 #include <sys/module.h>
51
52 #include <netinet/in.h>
53 #include <netinet/in_systm.h>
54 #include <netinet/ip.h>
55 #ifdef INET6
56 #include <netinet/ip6.h>
57 #endif
58
59 #include <netinet/ip_ecn.h>
60
61 /*
62 * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
63 */
64 void
ip_ecn_ingress(int mode,u_int8_t * outer,const u_int8_t * inner)65 ip_ecn_ingress(int mode, u_int8_t *outer, const u_int8_t *inner)
66 {
67 if (!outer || !inner)
68 panic("NULL pointer passed to ip_ecn_ingress");
69
70 *outer = *inner;
71 switch (mode) {
72 case ECN_ALLOWED: /* ECN allowed */
73 *outer &= ~IPTOS_ECN_CE;
74 break;
75 case ECN_FORBIDDEN: /* ECN forbidden */
76 *outer &= ~(IPTOS_ECN_ECT0 | IPTOS_ECN_CE);
77 break;
78 case ECN_NOCARE: /* no consideration to ECN */
79 break;
80 }
81 }
82
83 /*
84 * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
85 */
86 void
ip_ecn_egress(int mode,const u_int8_t * outer,u_int8_t * inner)87 ip_ecn_egress(int mode, const u_int8_t *outer, u_int8_t *inner)
88 {
89 if (!outer || !inner)
90 panic("NULL pointer passed to ip_ecn_egress");
91
92 switch (mode) {
93 case ECN_ALLOWED:
94 if (*outer & IPTOS_ECN_CE)
95 *inner |= IPTOS_ECN_CE;
96 break;
97 case ECN_FORBIDDEN: /* ECN forbidden */
98 case ECN_NOCARE: /* no consideration to ECN */
99 break;
100 }
101 }
102
103 #ifdef INET6
104 void
ip6_ecn_ingress(int mode,u_int32_t * outer,const u_int32_t * inner)105 ip6_ecn_ingress(int mode, u_int32_t *outer, const u_int32_t *inner)
106 {
107 u_int8_t outer8, inner8;
108
109 if (!outer || !inner)
110 panic("NULL pointer passed to ip6_ecn_ingress");
111
112 outer8 = (ntohl(*outer) >> 20) & 0xff;
113 inner8 = (ntohl(*inner) >> 20) & 0xff;
114 ip_ecn_ingress(mode, &outer8, &inner8);
115 *outer &= ~htonl(0xff << 20);
116 *outer |= htonl((u_int32_t)outer8 << 20);
117 }
118
119 void
ip6_ecn_egress(int mode,const u_int32_t * outer,u_int32_t * inner)120 ip6_ecn_egress(int mode, const u_int32_t *outer, u_int32_t *inner)
121 {
122 u_int8_t outer8, inner8;
123
124 if (!outer || !inner)
125 panic("NULL pointer passed to ip6_ecn_egress");
126
127 outer8 = (ntohl(*outer) >> 20) & 0xff;
128 inner8 = (ntohl(*inner) >> 20) & 0xff;
129 ip_ecn_egress(mode, &outer8, &inner8);
130 *inner &= ~htonl(0xff << 20);
131 *inner |= htonl((u_int32_t)inner8 << 20);
132 }
133 #endif
134
135 MODULE(MODULE_CLASS_MISC, ip_ecn, NULL);
136
137 static int
ip_ecn_modcmd(modcmd_t cmd,void * arg)138 ip_ecn_modcmd(modcmd_t cmd, void *arg)
139 {
140
141 switch (cmd) {
142 case MODULE_CMD_INIT:
143 case MODULE_CMD_FINI:
144 return 0;
145
146 default:
147 return ENOTTY;
148 }
149 }
150
151