NetBSD/sys/netinet/ip_ecn.c
rpaulo 2fb2ae3251 Import of TCP ECN algorithm for congestion control.
Both available for IPv4 and IPv6.
Basic implementation test results are available at
http://netbsd-soc.sourceforge.net/projects/ecn/testresults.html.

Work sponsored by the Google Summer of Code project 2006.
Special thanks to Kentaro Kurahone, Allen Briggs and Matt Thomas for their
help, comments and support during the project.
2006-09-05 00:29:35 +00:00

131 lines
3.8 KiB
C

/* $NetBSD: ip_ecn.c,v 1.15 2006/09/05 00:29:36 rpaulo Exp $ */
/* $KAME: ip_ecn.c,v 1.11 2001/05/03 16:09:29 itojun Exp $ */
/*
* Copyright (C) 1999 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/*
* ECN consideration on tunnel ingress/egress operation.
* http://www.aciri.org/floyd/papers/draft-ipsec-ecn-00.txt
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ip_ecn.c,v 1.15 2006/09/05 00:29:36 rpaulo Exp $");
#include "opt_inet.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif
#include <netinet/ip_ecn.h>
/*
* modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
*/
void
ip_ecn_ingress(int mode, u_int8_t *outer, const u_int8_t *inner)
{
if (!outer || !inner)
panic("NULL pointer passed to ip_ecn_ingress");
*outer = *inner;
switch (mode) {
case ECN_ALLOWED: /* ECN allowed */
*outer &= ~IPTOS_ECN_CE;
break;
case ECN_FORBIDDEN: /* ECN forbidden */
*outer &= ~(IPTOS_ECN_ECT0 | IPTOS_ECN_CE);
break;
case ECN_NOCARE: /* no consideration to ECN */
break;
}
}
/*
* modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
*/
void
ip_ecn_egress(int mode, const u_int8_t *outer, u_int8_t *inner)
{
if (!outer || !inner)
panic("NULL pointer passed to ip_ecn_egress");
switch (mode) {
case ECN_ALLOWED:
if (*outer & IPTOS_ECN_CE)
*inner |= IPTOS_ECN_CE;
break;
case ECN_FORBIDDEN: /* ECN forbidden */
case ECN_NOCARE: /* no consideration to ECN */
break;
}
}
#ifdef INET6
void
ip6_ecn_ingress(int mode, u_int32_t *outer, const u_int32_t *inner)
{
u_int8_t outer8, inner8;
if (!outer || !inner)
panic("NULL pointer passed to ip6_ecn_ingress");
outer8 = (ntohl(*outer) >> 20) & 0xff;
inner8 = (ntohl(*inner) >> 20) & 0xff;
ip_ecn_ingress(mode, &outer8, &inner8);
*outer &= ~htonl(0xff << 20);
*outer |= htonl((u_int32_t)outer8 << 20);
}
void
ip6_ecn_egress(int mode, const u_int32_t *outer, u_int32_t *inner)
{
u_int8_t outer8, inner8;
if (!outer || !inner)
panic("NULL pointer passed to ip6_ecn_egress");
outer8 = (ntohl(*outer) >> 20) & 0xff;
inner8 = (ntohl(*inner) >> 20) & 0xff;
ip_ecn_egress(mode, &outer8, &inner8);
*inner &= ~htonl(0xff << 20);
*inner |= htonl((u_int32_t)inner8 << 20);
}
#endif