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 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 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 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 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 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