bsd/netinet/ip_ecn.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (C) 1999 WIDE Project.
  27  * All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. Neither the name of the project nor the names of its contributors
  38  *    may be used to endorse or promote products derived from this software
  39  *    without specific prior written permission.
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  */
  54 /*
  55  * ECN consideration on tunnel ingress/egress operation.
  56  * http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
  57  */
  58
  59 #include <sys/param.h>
  60 #include <sys/systm.h>
  61 #include <sys/malloc.h>
  62 #include <sys/mbuf.h>
  63 #include <sys/errno.h>
  64
  65 #include <netinet/in.h>
  66 #include <netinet/in_systm.h>
  67 #include <netinet/ip.h>
  68 #if INET6
  69 #include <netinet/ip6.h>
  70 #endif
  71
  72 #include <netinet/ip_ecn.h>
  73 #if INET6
  74 #include <netinet6/ip6_ecn.h>
  75 #endif
  76
  77 /*
  78  * modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
  79  */
  80 void
  81 ip_ecn_ingress(mode, outer, inner)
  82         int mode;
  83         u_int8_t *outer;
  84         const u_int8_t *inner;
  85 {
  86         if (!outer || !inner)
  87                 panic("NULL pointer passed to ip_ecn_ingress");
  88
  89         *outer = *inner;
  90         switch (mode) {
  91         case ECN_ALLOWED:               /* ECN allowed */
  92                 *outer &= ~IPTOS_CE;
  93                 break;
  94         case ECN_FORBIDDEN:             /* ECN forbidden */
  95                 *outer &= ~(IPTOS_ECT | IPTOS_CE);
  96                 break;
  97         case ECN_NOCARE:        /* no consideration to ECN */
  98                 break;
  99         }
 100 }
 101
 102 /*
 103  * modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
 104  */
 105 void
 106 ip_ecn_egress(mode, outer, inner)
 107         int mode;
 108         const u_int8_t *outer;
 109         u_int8_t *inner;
 110 {
 111         if (!outer || !inner)
 112                 panic("NULL pointer passed to ip_ecn_egress");
 113
 114         switch (mode) {
 115         case ECN_ALLOWED:
 116                 if (*outer & IPTOS_CE)
 117                         *inner |= IPTOS_CE;
 118                 break;
 119         case ECN_FORBIDDEN:             /* ECN forbidden */
 120         case ECN_NOCARE:        /* no consideration to ECN */
 121                 break;
 122         }
 123 }
 124
 125 #if INET6
 126 void
 127 ip6_ecn_ingress(mode, outer, inner)
 128         int mode;
 129         u_int32_t *outer;
 130         const u_int32_t *inner;
 131 {
 132         u_int8_t outer8, inner8;
 133
 134         if (!outer || !inner)
 135                 panic("NULL pointer passed to ip6_ecn_ingress");
 136
 137         inner8 = (ntohl(*inner) >> 20) & 0xff;
 138         ip_ecn_ingress(mode, &outer8, &inner8);
 139         *outer &= ~htonl(0xff << 20);
 140         *outer |= htonl((u_int32_t)outer8 << 20);
 141 }
 142
 143 void
 144 ip6_ecn_egress(mode, outer, inner)
 145         int mode;
 146         const u_int32_t *outer;
 147         u_int32_t *inner;
 148 {
 149         u_int8_t outer8, inner8;
 150
 151         if (!outer || !inner)
 152                 panic("NULL pointer passed to ip6_ecn_egress");
 153
 154         outer8 = (ntohl(*outer) >> 20) & 0xff;
 155         ip_ecn_egress(mode, &outer8, &inner8);
 156         *inner &= ~htonl(0xff << 20);
 157         *inner |= htonl((u_int32_t)inner8 << 20);
 158 }
 159 #endif