NetBSD/sys/netinet/ip_gre.c

272 lines
6.6 KiB
C

/* $NetBSD: ip_gre.c,v 1.1 1998/09/13 20:27:48 hwr Exp $ */
/*
* (c) 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Heiko W.Rupp <hwr@pilhuhn.de>
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* deencapsulate GRE packets and send them on
* output half is in net/ip_gre.[ch]
*
*/
#include "gre.h"
#if NGRE > 0
#include "opt_inet.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/ioctl.h>
#include <sys/syslog.h>
#include <net/ethertypes.h>
#include <net/if.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/raw_cb.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#else
Huh? ip_gre input without IP?
#endif
#ifdef NS
#include <netns/ns.h>
#include <netns/ns_if.h>
#endif
#ifdef NETATALK
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#include <netatalk/at_extern.h>
#endif
#include <machine/stdarg.h>
#include "ip_gre.h"
#include <net/if_gre.h>
extern struct gre_softc gre_softc[NGRE];
/*
* De-encapsulate a packet and feed it back through ip input (this
* routine is called whenever IP gets a packet with proto type
* IPPROTO_GRE and a local destination address).
* This really is simple
*/
void
#if __STDC__
gre_input(struct mbuf *m, ...)
#else
gre_input(m, va_alist)
struct mbuf *m;
va_dcl
#endif
{
register int hlen,ret;
va_list ap;
va_start(ap, m);
hlen = va_arg(ap, int);
va_end(ap);
ret=gre_input2(m,hlen,IPPROTO_GRE);
/*
* ret == 0 : packet not processed, but input from here
* means no matching tunnel that is up is found,
* so we can just free the mbuf and return
*/
if (ret==0)
m_freem(m);
}
/*
* decapsulate.
* Does the real work and is called from gre_input() (above)
* and also from ipip_input() (ip_mroute.c)
* returns 0 if packet is not yet processed
* and 1 if it needs no further processing
* proto is the protocol number of the "calling" foo_input()
* routine.
*/
int
gre_input2(struct mbuf *m ,int hlen,u_char proto)
{
register struct ip *ip = mtod(m, struct ip *);
register struct greip *gip = mtod(m, struct greip *);
register int s,i;
register struct ifqueue *ifq;
struct gre_softc *sc;
u_short flags;
i=0;
do {
sc=&gre_softc[i];
if((sc->g_dst.s_addr == ip->ip_src.s_addr) &&
(sc->g_src.s_addr == ip->ip_dst.s_addr))
break;
i++;
} while(i<NGRE);
if ((i<NGRE) && ((sc->sc_if.if_flags & IFF_UP) == IFF_UP)) {
/* found matching tunnel that is up */
sc->sc_if.if_ipackets++;
sc->sc_if.if_ibytes+=m->m_pkthdr.len;
} else { /* no matching tunnel or match, but tunnel down */
return 0;
}
switch (proto) {
case IPPROTO_GRE:
hlen += sizeof (struct gre_h);
/* process GRE flags as packet can be of variable len */
flags = ntohs(gip->gi_flags);
/* Checksum & Offset are present */
if ((flags & GRE_CP) | (flags & GRE_RP))
hlen += 4;
/* We don't support routing fields (variable length) */
if (flags & GRE_RP)
return(0);
if (flags & GRE_KP)
hlen += 4;
if (flags & GRE_SP)
hlen +=4;
switch (ntohs(gip->gi_ptype)) { /* ethertypes */
case ETHERTYPE_IP: /* shouldn't need a schednetisr(), as */
ifq = &ipintrq; /* we are in ip_input */
break;
#ifdef NS
case ETHERTYPE_NS:
ifq = &nsintrq;
schednetisr(NETISR_NS);
break;
#endif
#ifdef NETATALK
case ETHERTYPE_AT:
ifq = &atintrq1;
schednetisr(NETISR_ATALK);
break;
#endif
case ETHERTYPE_IPV6:
/* FALLTHROUGH */
default: /* others not yet supported */
return(0);
}
break;
case IPPROTO_IPIP:
ifq = &ipintrq;
break;
default:
/* others not yet supported */
return(0);
}
m->m_data += hlen;
m->m_len -= hlen;
m->m_pkthdr.len -= hlen;
s = splimp(); /* possible */
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
m_freem(m);
} else {
IF_ENQUEUE(ifq,m);
}
splx(s);
return(1); /* packet is done, no further processing needed */
}
#ifndef MROUTING
/*
* Well if MROUTING is not defined, the ipip_input function in
* ip_mroute.c gets never called, so IPIP packets coming over the
* tunnel can't be processed. (Not exactly true. They go to raw ip
* that also can't cope ).
*/
void
#if __STDC__
gre_ipip_input(struct mbuf *m, ...)
#else
ipip_input(m, va_alist)
struct mbuf *m;
va_dcl
#endif
{
register int hlen;
va_list ap;
va_start(ap, m);
hlen = va_arg(ap, int);
va_end(ap);
/*
* return == 0 means, that the packet is not preocessed, but
* as we are the only ones to decapsulate IPIP, and are not able,
* then we can just dump it.
*/
if(gre_input2(m,hlen,IPPROTO_IPIP)==0)
m_freem(m);
}
#endif /* ifndef MROUTING */
#endif /* if NGRE > 0 */