sys/netinet/ip_ecn.c

   1 /*      $FreeBSD: src/sys/netinet/ip_ecn.c,v 1.1.2.3 2002/04/17 07:50:17 suz Exp $      */
   2 /*      $DragonFly: src/sys/netinet/ip_ecn.c,v 1.3 2006/01/14 11:33:50 swildner Exp $   */
   3 /*      $KAME: ip_ecn.c,v 1.11 2001/05/03 16:09:29 itojun Exp $ */
   4
   5 /*
   6  * Copyright (C) 1999 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  */
  34 /*
  35  * ECN consideration on tunnel ingress/egress operation.
  36  * http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
  37  */
  38
  39 #include "opt_inet.h"
  40 #include "opt_inet6.h"
  41
  42 #include <sys/param.h>
  43 #include <sys/systm.h>
  44 #include <sys/malloc.h>
  45 #include <sys/mbuf.h>
  46 #include <sys/errno.h>
  47
  48 #include <netinet/in.h>
  49 #include <netinet/in_systm.h>
  50 #include <netinet/ip.h>
  51 #ifdef INET6
  52 #include <netinet/ip6.h>
  53 #endif
  54
  55 #include <netinet/ip_ecn.h>
  56 #ifdef INET6
  57 #include <netinet6/ip6_ecn.h>
  58 #endif
  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_CE;
  73                 break;
  74         case ECN_FORBIDDEN:             /* ECN forbidden */
  75                 *outer &= ~(IPTOS_ECT | IPTOS_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_CE)
  94                         *inner |= IPTOS_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