bsd/netinet/ip_ecn.c

   1 /*
   2  * Copyright (c) 2000, 2007, 2015 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * Copyright (C) 1999 WIDE Project.
  30  * All rights reserved.
  31  *
  32  * Redistribution and use in source and binary forms, with or without
  33  * modification, are permitted provided that the following conditions
  34  * are met:
  35  * 1. Redistributions of source code must retain the above copyright
  36  *    notice, this list of conditions and the following disclaimer.
  37  * 2. Redistributions in binary form must reproduce the above copyright
  38  *    notice, this list of conditions and the following disclaimer in the
  39  *    documentation and/or other materials provided with the distribution.
  40  * 3. Neither the name of the project nor the names of its contributors
  41  *    may be used to endorse or promote products derived from this software
  42  *    without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  45  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  47  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  48  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  49  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  50  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  51  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  52  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  53  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  54  * SUCH DAMAGE.
  55  *
  56  */
  57 /*
  58  * ECN consideration on tunnel ingress/egress operation.
  59  * http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
  60  */
  61
  62 #include <sys/param.h>
  63 #include <sys/systm.h>
  64 #include <sys/malloc.h>
  65 #include <sys/mbuf.h>
  66 #include <sys/errno.h>
  67
  68 #include <netinet/in.h>
  69 #include <netinet/in_systm.h>
  70 #include <netinet/ip.h>
  71 #if INET6
  72 #include <netinet/ip6.h>
  73 #endif
  74
  75 #include <netinet/ip_ecn.h>
  76 #if INET6
  77 #include <netinet6/ip6_ecn.h>
  78 #endif
  79
  80 /*
  81  * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
  82  */
  83 void
  84 ip_ecn_ingress(mode, outer, inner)
  85         int mode;
  86         u_int8_t *outer;
  87         const u_int8_t *inner;
  88 {
  89         if (!outer || !inner)
  90                 panic("NULL pointer passed to ip_ecn_ingress");
  91
  92         *outer = *inner;
  93         switch (mode) {
  94         case ECN_NORMAL:                /* ECN normal mode, copy flags */
  95                 break;
  96         case ECN_COMPATIBILITY:         /* ECN compatibility mode */
  97                 *outer &= ~IPTOS_ECN_MASK;
  98                 break;
  99         case ECN_NOCARE:        /* no consideration to ECN */
 100                 break;
 101         }
 102 }
 103
 104 /*
 105  * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
 106  */
 107 int
 108 ip_ecn_egress(mode, outer, inner)
 109         int mode;
 110         const u_int8_t *outer;
 111         u_int8_t *inner;
 112 {
 113         if (!outer || !inner)
 114                 panic("NULL pointer passed to ip_ecn_egress");
 115
 116         switch (mode) {
 117         /* Process ECN for both normal and compatibility modes */
 118         case ECN_NORMAL:
 119         case ECN_COMPATIBILITY:
 120                 if ((*outer & IPTOS_ECN_MASK) == IPTOS_ECN_CE) {
 121                         if ((*inner & IPTOS_ECN_MASK) == IPTOS_ECN_NOTECT) {
 122                                 /* Drop */
 123                                 return (0);
 124                         } else {
 125                                 *inner |= IPTOS_ECN_CE;
 126                         }
 127                 } else if ((*outer & IPTOS_ECN_MASK) == IPTOS_ECN_ECT1 &&
 128                                    (*inner & IPTOS_ECN_MASK) == IPTOS_ECN_ECT0) {
 129                         *inner = *outer;
 130                 }
 131                 break;
 132         case ECN_NOCARE:        /* no consideration to ECN */
 133                 break;
 134         }
 135         return (1);
 136 }
 137
 138 #if INET6
 139 void
 140 ip6_ecn_ingress(mode, outer, inner)
 141         int mode;
 142         u_int32_t *outer;
 143         const u_int32_t *inner;
 144 {
 145         u_int8_t outer8, inner8;
 146
 147         if (!outer || !inner)
 148                 panic("NULL pointer passed to ip6_ecn_ingress");
 149
 150         inner8 = (ntohl(*inner) >> 20) & 0xff;
 151         ip_ecn_ingress(mode, &outer8, &inner8);
 152         *outer &= ~htonl(0xff << 20);
 153         *outer |= htonl((u_int32_t)outer8 << 20);
 154 }
 155
 156 int
 157 ip6_ecn_egress(mode, outer, inner)
 158         int mode;
 159         const u_int32_t *outer;
 160         u_int32_t *inner;
 161 {
 162         u_int8_t outer8, inner8;
 163
 164         if (!outer || !inner)
 165                 panic("NULL pointer passed to ip6_ecn_egress");
 166
 167         outer8 = (ntohl(*outer) >> 20) & 0xff;
 168         inner8 = (ntohl(*inner) >> 20) & 0xff;
 169         if (ip_ecn_egress(mode, &outer8, &inner8) == 0) {
 170                 return (0);
 171         }
 172         *inner &= ~htonl(0xff << 20);
 173         *inner |= htonl((u_int32_t)inner8 << 20);
 174         return (1);
 175 }
 176
 177 /*
 178  * Modify outer IPv6 ECN (Traffic Class) field according to inner IPv4 TOS field
 179  * on ingress operation (tunnel encapsulation).
 180  */
 181 void
 182 ip46_ecn_ingress(mode, outer, tos)
 183         int mode;
 184         u_int32_t *outer;
 185         const u_int8_t *tos;
 186 {
 187         u_int8_t outer8;
 188
 189         if (!outer || !tos)
 190                 panic("NULL pointer passed to ip46_ecn_ingress");
 191
 192         ip_ecn_ingress(mode, &outer8, tos);
 193         *outer &= ~htonl(0xff << 20);
 194         *outer |= htonl((u_int32_t)outer8 << 20);
 195 }
 196
 197 /*
 198  * Modify inner IPv4 ECN (TOS) field according to output IPv6 ECN (Traffic Class)
 199  * on egress operation (tunnel decapsulation).
 200  */
 201 int
 202 ip46_ecn_egress(mode, outer, tos)
 203         int mode;
 204         const u_int32_t *outer;
 205         u_int8_t *tos;
 206 {
 207         u_int8_t outer8;
 208
 209         if (!outer || !tos)
 210                 panic("NULL pointer passed to ip46_ecn_egress");
 211
 212         outer8 = (ntohl(*outer) >> 20) & 0xff;
 213         return ip_ecn_egress(mode, &outer8, tos);
 214 }
 215
 216 /*
 217  * Modify outer IPv4 TOS field according to inner IPv6 ECN (Traffic Class)
 218  * on ingress operation (tunnel encapsulation).
 219  */
 220 void
 221 ip64_ecn_ingress(mode, outer, inner)
 222         int mode;
 223         u_int8_t *outer;
 224         const u_int32_t *inner;
 225 {
 226         u_int8_t inner8;
 227
 228         if (!outer || ! inner)
 229                 panic("NULL pointer passed to ip64_ecn_ingress");
 230
 231         inner8 = (ntohl(*inner) >> 20) & 0xff;
 232         ip_ecn_ingress(mode, outer, &inner8);
 233 }
 234
 235 /*
 236  * Modify inner IPv6 ECN (Traffic Class) according to outer IPv4 TOS field
 237  * on egress operation (tunnel decapsulation).
 238  */
 239 int
 240 ip64_ecn_egress(mode, outer, inner)
 241         int mode;
 242         const u_int8_t *outer;
 243         u_int32_t *inner;
 244 {
 245         u_int8_t inner8;
 246
 247         if (!outer || !inner)
 248                 panic("NULL pointer passed to ip64_ecn_egress");
 249
 250         inner8 = (ntohl(*inner) >> 20) & 0xff;
 251         if (ip_ecn_egress(mode, outer, &inner8) == 0) {
 252                 return (0);
 253         }
 254
 255         *inner &= ~htonl(0xff << 20);
 256         *inner |= htonl((u_int32_t)inner8 << 20);
 257         return (1);
 258 }
 259
 260 #endif