74da783549
- implement the tunnel egress rule in ip_ecn_egress() in ip_ecn.c. make ip{,6}_ecn_egress() return integer to tell the caller that this packet should be dropped. - handle ECN at fragment reassembly in ip_input.c and frag6.c. Obtained from: KAME
201 lines
5.8 KiB
C
201 lines
5.8 KiB
C
/* $FreeBSD$ */
|
|
/* $KAME: ip_ecn.c,v 1.12 2002/01/07 11:34:47 kjc 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 "opt_inet.h"
|
|
#include "opt_inet6.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.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>
|
|
#ifdef INET6
|
|
#include <netinet6/ip6_ecn.h>
|
|
#endif
|
|
|
|
/*
|
|
* ECN and TOS (or TCLASS) processing rules at tunnel encapsulation and
|
|
* decapsulation from RFC3168:
|
|
*
|
|
* Outer Hdr at Inner Hdr at
|
|
* Encapsulator Decapsulator
|
|
* Header fields: -------------------- ------------
|
|
* DS Field copied from inner hdr no change
|
|
* ECN Field constructed by (I) constructed by (E)
|
|
*
|
|
* ECN_ALLOWED (full functionality):
|
|
* (I) if the ECN field in the inner header is set to CE, then set the
|
|
* ECN field in the outer header to ECT(0).
|
|
* otherwise, copy the ECN field to the outer header.
|
|
*
|
|
* (E) if the ECN field in the outer header is set to CE and the ECN
|
|
* field of the inner header is not-ECT, drop the packet.
|
|
* if the ECN field in the inner header is set to ECT(0) or ECT(1)
|
|
* and the ECN field in the outer header is set to CE, then copy CE to
|
|
* the inner header. otherwise, make no change to the inner header.
|
|
*
|
|
* ECN_FORBIDDEN (limited functionality):
|
|
* (I) set the ECN field to not-ECT in the outer header.
|
|
*
|
|
* (E) if the ECN field in the outer header is set to CE, drop the packet.
|
|
* otherwise, make no change to the ECN field in the inner header.
|
|
*
|
|
* the drop rule is for backward compatibility and protection against
|
|
* erasure of CE.
|
|
*/
|
|
|
|
/*
|
|
* modify outer ECN (TOS) field on ingress operation (tunnel encapsulation).
|
|
*/
|
|
void
|
|
ip_ecn_ingress(mode, outer, inner)
|
|
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 */
|
|
/*
|
|
* full-functionality: if the inner is CE, set ECT(0)
|
|
* to the outer. otherwise, copy the ECN field.
|
|
*/
|
|
if ((*inner & IPTOS_ECN_MASK) == IPTOS_ECN_CE)
|
|
*outer &= ~IPTOS_ECN_ECT1;
|
|
break;
|
|
case ECN_FORBIDDEN: /* ECN forbidden */
|
|
/*
|
|
* limited-functionality: set not-ECT to the outer
|
|
*/
|
|
*outer &= ~IPTOS_ECN_MASK;
|
|
break;
|
|
case ECN_NOCARE: /* no consideration to ECN */
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* modify inner ECN (TOS) field on egress operation (tunnel decapsulation).
|
|
* the caller should drop the packet if the return value is 0.
|
|
*/
|
|
int
|
|
ip_ecn_egress(mode, outer, inner)
|
|
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:
|
|
/*
|
|
* full-functionality: if the outer is CE and the inner is
|
|
* not-ECT, should drop it. otherwise, copy CE.
|
|
*/
|
|
if ((*outer & IPTOS_ECN_MASK) == IPTOS_ECN_CE) {
|
|
if ((*inner & IPTOS_ECN_MASK) == IPTOS_ECN_NOTECT)
|
|
return (0);
|
|
*inner |= IPTOS_ECN_CE;
|
|
}
|
|
break;
|
|
case ECN_FORBIDDEN: /* ECN forbidden */
|
|
/*
|
|
* limited-functionality: if the outer is CE, should drop it.
|
|
* otherwise, leave the inner.
|
|
*/
|
|
if ((*outer & IPTOS_ECN_MASK) == IPTOS_ECN_CE)
|
|
return (0);
|
|
break;
|
|
case ECN_NOCARE: /* no consideration to ECN */
|
|
break;
|
|
}
|
|
return (1);
|
|
}
|
|
|
|
#ifdef INET6
|
|
void
|
|
ip6_ecn_ingress(mode, outer, inner)
|
|
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");
|
|
|
|
inner8 = (ntohl(*inner) >> 20) & 0xff;
|
|
ip_ecn_ingress(mode, &outer8, &inner8);
|
|
*outer &= ~htonl(0xff << 20);
|
|
*outer |= htonl((u_int32_t)outer8 << 20);
|
|
}
|
|
|
|
int
|
|
ip6_ecn_egress(mode, outer, inner)
|
|
int mode;
|
|
const u_int32_t *outer;
|
|
u_int32_t *inner;
|
|
{
|
|
u_int8_t outer8, inner8, oinner8;
|
|
|
|
if (!outer || !inner)
|
|
panic("NULL pointer passed to ip6_ecn_egress");
|
|
|
|
outer8 = (ntohl(*outer) >> 20) & 0xff;
|
|
inner8 = oinner8 = (ntohl(*inner) >> 20) & 0xff;
|
|
if (ip_ecn_egress(mode, &outer8, &inner8) == 0)
|
|
return (0);
|
|
if (inner8 != oinner8) {
|
|
*inner &= ~htonl(0xff << 20);
|
|
*inner |= htonl((u_int32_t)inner8 << 20);
|
|
}
|
|
return (1);
|
|
}
|
|
#endif
|