bsd/netinet/ip_ecn.c

   1 /*
   2  * Copyright (c) 2000,2007 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_ALLOWED:               /* ECN allowed */
  95                 *outer &= ~IPTOS_CE;
  96                 break;
  97         case ECN_FORBIDDEN:             /* ECN forbidden */
  98                 *outer &= ~(IPTOS_ECT | IPTOS_CE);
  99                 break;
 100         case ECN_NOCARE:        /* no consideration to ECN */
 101                 break;
 102         }
 103 }
 104
 105 /*
 106  * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
 107  */
 108 void
 109 ip_ecn_egress(mode, outer, inner)
 110         int mode;
 111         const u_int8_t *outer;
 112         u_int8_t *inner;
 113 {
 114         if (!outer || !inner)
 115                 panic("NULL pointer passed to ip_ecn_egress");
 116
 117         switch (mode) {
 118         case ECN_ALLOWED:
 119                 if (*outer & IPTOS_CE)
 120                         *inner |= IPTOS_CE;
 121                 break;
 122         case ECN_FORBIDDEN:             /* ECN forbidden */
 123         case ECN_NOCARE:        /* no consideration to ECN */
 124                 break;
 125         }
 126 }
 127
 128 #if INET6
 129 void
 130 ip6_ecn_ingress(mode, outer, inner)
 131         int mode;
 132         u_int32_t *outer;
 133         const u_int32_t *inner;
 134 {
 135         u_int8_t outer8, inner8;
 136
 137         if (!outer || !inner)
 138                 panic("NULL pointer passed to ip6_ecn_ingress");
 139
 140         inner8 = (ntohl(*inner) >> 20) & 0xff;
 141         ip_ecn_ingress(mode, &outer8, &inner8);
 142         *outer &= ~htonl(0xff << 20);
 143         *outer |= htonl((u_int32_t)outer8 << 20);
 144 }
 145
 146 void
 147 ip6_ecn_egress(mode, outer, inner)
 148         int mode;
 149         const u_int32_t *outer;
 150         u_int32_t *inner;
 151 {
 152         u_int8_t outer8, inner8;
 153
 154         if (!outer || !inner)
 155                 panic("NULL pointer passed to ip6_ecn_egress");
 156
 157         outer8 = (ntohl(*outer) >> 20) & 0xff;
 158         inner8 = (ntohl(*inner) >> 20) & 0xff;
 159         ip_ecn_egress(mode, &outer8, &inner8);
 160         *inner &= ~htonl(0xff << 20);
 161         *inner |= htonl((u_int32_t)inner8 << 20);
 162 }
 163 #endif