1 /* $NetBSD: ip_ecn.c,v 1.12 2002/04/10 09:18:57 itojun 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 1.12 2002/04/10 09:18:57 itojun Exp $"); 40 41 #include "opt_inet.h" 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/errno.h> 48 49 #include <netinet/in.h> 50 #include <netinet/in_systm.h> 51 #include <netinet/ip.h> 52 #ifdef INET6 53 #include <netinet/ip6.h> 54 #endif 55 56 #include <netinet/ip_ecn.h> 57 58 /* 59 * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation). 60 */ 61 void 62 ip_ecn_ingress(mode, outer, inner) 63 int mode; 64 u_int8_t *outer; 65 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_CE; 74 break; 75 case ECN_FORBIDDEN: /* ECN forbidden */ 76 *outer &= ~(IPTOS_ECT | IPTOS_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 87 ip_ecn_egress(mode, outer, inner) 88 int mode; 89 const u_int8_t *outer; 90 u_int8_t *inner; 91 { 92 if (!outer || !inner) 93 panic("NULL pointer passed to ip_ecn_egress"); 94 95 switch (mode) { 96 case ECN_ALLOWED: 97 if (*outer & IPTOS_CE) 98 *inner |= IPTOS_CE; 99 break; 100 case ECN_FORBIDDEN: /* ECN forbidden */ 101 case ECN_NOCARE: /* no consideration to ECN */ 102 break; 103 } 104 } 105 106 #ifdef INET6 107 void 108 ip6_ecn_ingress(mode, outer, inner) 109 int mode; 110 u_int32_t *outer; 111 const u_int32_t *inner; 112 { 113 u_int8_t outer8, inner8; 114 115 if (!outer || !inner) 116 panic("NULL pointer passed to ip6_ecn_ingress"); 117 118 outer8 = (ntohl(*outer) >> 20) & 0xff; 119 inner8 = (ntohl(*inner) >> 20) & 0xff; 120 ip_ecn_ingress(mode, &outer8, &inner8); 121 *outer &= ~htonl(0xff << 20); 122 *outer |= htonl((u_int32_t)outer8 << 20); 123 } 124 125 void 126 ip6_ecn_egress(mode, outer, inner) 127 int mode; 128 const u_int32_t *outer; 129 u_int32_t *inner; 130 { 131 u_int8_t outer8, inner8; 132 133 if (!outer || !inner) 134 panic("NULL pointer passed to ip6_ecn_egress"); 135 136 outer8 = (ntohl(*outer) >> 20) & 0xff; 137 inner8 = (ntohl(*inner) >> 20) & 0xff; 138 ip_ecn_egress(mode, &outer8, &inner8); 139 *inner &= ~htonl(0xff << 20); 140 *inner |= htonl((u_int32_t)inner8 << 20); 141 } 142 #endif 143