1 /* $NetBSD: ip_ecn.c,v 1.16 2015/08/24 22:21:26 pooka 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 1.16 2015/08/24 22:21:26 pooka 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 51 #include <netinet/in.h> 52 #include <netinet/in_systm.h> 53 #include <netinet/ip.h> 54 #ifdef INET6 55 #include <netinet/ip6.h> 56 #endif 57 58 #include <netinet/ip_ecn.h> 59 60 /* 61 * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation). 62 */ 63 void 64 ip_ecn_ingress(int mode, u_int8_t *outer, const u_int8_t *inner) 65 { 66 if (!outer || !inner) 67 panic("NULL pointer passed to ip_ecn_ingress"); 68 69 *outer = *inner; 70 switch (mode) { 71 case ECN_ALLOWED: /* ECN allowed */ 72 *outer &= ~IPTOS_ECN_CE; 73 break; 74 case ECN_FORBIDDEN: /* ECN forbidden */ 75 *outer &= ~(IPTOS_ECN_ECT0 | IPTOS_ECN_CE); 76 break; 77 case ECN_NOCARE: /* no consideration to ECN */ 78 break; 79 } 80 } 81 82 /* 83 * modify inner ECN (TOS) field on egress operation (tunnel decapsulation). 84 */ 85 void 86 ip_ecn_egress(int mode, const u_int8_t *outer, u_int8_t *inner) 87 { 88 if (!outer || !inner) 89 panic("NULL pointer passed to ip_ecn_egress"); 90 91 switch (mode) { 92 case ECN_ALLOWED: 93 if (*outer & IPTOS_ECN_CE) 94 *inner |= IPTOS_ECN_CE; 95 break; 96 case ECN_FORBIDDEN: /* ECN forbidden */ 97 case ECN_NOCARE: /* no consideration to ECN */ 98 break; 99 } 100 } 101 102 #ifdef INET6 103 void 104 ip6_ecn_ingress(int mode, u_int32_t *outer, const u_int32_t *inner) 105 { 106 u_int8_t outer8, inner8; 107 108 if (!outer || !inner) 109 panic("NULL pointer passed to ip6_ecn_ingress"); 110 111 outer8 = (ntohl(*outer) >> 20) & 0xff; 112 inner8 = (ntohl(*inner) >> 20) & 0xff; 113 ip_ecn_ingress(mode, &outer8, &inner8); 114 *outer &= ~htonl(0xff << 20); 115 *outer |= htonl((u_int32_t)outer8 << 20); 116 } 117 118 void 119 ip6_ecn_egress(int mode, const u_int32_t *outer, u_int32_t *inner) 120 { 121 u_int8_t outer8, inner8; 122 123 if (!outer || !inner) 124 panic("NULL pointer passed to ip6_ecn_egress"); 125 126 outer8 = (ntohl(*outer) >> 20) & 0xff; 127 inner8 = (ntohl(*inner) >> 20) & 0xff; 128 ip_ecn_egress(mode, &outer8, &inner8); 129 *inner &= ~htonl(0xff << 20); 130 *inner |= htonl((u_int32_t)inner8 << 20); 131 } 132 #endif 133