if_dummy.c   [plain text]


/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1982, 1986, 1993
 *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 */
/*
 * derived from 
 *	@(#)if_loop.c	8.1 (Berkeley) 6/10/93
 * Id: if_loop.c,v 1.22 1996/06/19 16:24:10 wollman Exp
 */

/*
 * Loopback interface driver for protocol testing and timing.
 */
#if BSD310
#include "opt_inet.h"
#endif
#include "dummy.h"
#if NDUMMY > 0

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/errno.h>
#include <sys/time.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/bpf.h>

#if	INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#endif

#if IPX
#include <netipx/ipx.h>
#include <netipx/ipx_if.h>
#endif

#if INET6
#ifndef INET
#include <netinet/in.h>
#endif
#include <netinet6/in6_var.h>
#include <netinet6/ip6.h>
#endif

#if NETATALK
#include <netinet/if_ether.h>
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#endif NETATALK

#include "bpfilter.h"

static int dummyioctl(struct ifnet *, u_long, caddr_t);
int dummyoutput(struct ifnet *, register struct mbuf *, struct sockaddr *,
	register struct rtentry *);
static void dummyrtrequest(int, struct rtentry *, struct sockaddr *);

static void dummyattach(void *);
PSEUDO_SET(dummyattach, if_dummy);

#if TINY_DUMMYMTU
#define	DUMMYMTU	(1024+512)
#else
#define DUMMYMTU	16384
#endif
#define HAVE_OLD_BPF 1

static struct	ifnet dummyif[NDUMMY];

/* ARGSUSED */
static void
dummyattach(dummy)
	void *dummy;
{
	register struct ifnet *ifp;
	register int i = 0;

	for (i = 0; i < NDUMMY; i++) {
		ifp = &dummyif[i];
#if defined(__NetBSD__) || defined(__OpenBSD__)
		sprintf(ifp->if_xname, "dummy%d", i);
#else
		ifp->if_name = "dummy";
		ifp->if_unit = i;
#endif
#ifndef __bsdi__
		ifp->if_softc = NULL;
#endif
		ifp->if_mtu = DUMMYMTU;
		/* Change to BROADCAST experimentaly to announce its prefix. */
		ifp->if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
		ifp->if_ioctl = dummyioctl;
		ifp->if_output = dummyoutput;
		ifp->if_type = IFT_DUMMY;
		ifp->if_hdrlen = 0;
		ifp->if_addrlen = 0;
		if_attach(ifp);
#if NBPFILTER > 0
#ifdef HAVE_OLD_BPF
		bpfattach(ifp, DLT_NULL, sizeof(u_int));
#else
		bpfattach(&ifp->if_bpf, ifp, DLT_NULL, sizeof(u_int));
#endif
#endif
	}
}

int
dummyoutput(ifp, m, dst, rt)
	struct ifnet *ifp;
	register struct mbuf *m;
	struct sockaddr *dst;
	register struct rtentry *rt;
{

	if ((m->m_flags & M_PKTHDR) == 0)
		panic("dummyoutput no HDR");
#if NBPFILTER > 0
	/* BPF write needs to be handled specially */
	if (dst->sa_family == AF_UNSPEC) {
		dst->sa_family = *(mtod(m, int *));
		m->m_len -= sizeof(int);
		m->m_pkthdr.len -= sizeof(int);
		m->m_data += sizeof(int);
	}

	if (ifp->if_bpf) {
		/*
		 * We need to prepend the address family as
		 * a four byte field.  Cons up a dummy header
		 * to pacify bpf.  This is safe because bpf
		 * will only read from the mbuf (i.e., it won't
		 * try to free it or keep a pointer a to it).
		 */
		struct mbuf m0;
		u_int af = dst->sa_family;

		m0.m_next = m;
		m0.m_len = 4;
		m0.m_data = (char *)&af;

#ifdef HAVE_OLD_BPF
		bpf_mtap(ifp, &m0);
#else
		bpf_mtap(ifp->if_bpf, &m0);
#endif
	}
#endif
	m->m_pkthdr.rcvif = ifp;

	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
		m_freem(m);
		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
		        rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
	}
	ifp->if_opackets++;
	ifp->if_obytes += m->m_pkthdr.len;
	proto_inject(dst->sa_family, m);
	ifp->if_ipackets++;
	ifp->if_ibytes += m->m_pkthdr.len;
	return (0);
}

/* ARGSUSED */
static void
dummyrtrequest(cmd, rt, sa)
	int cmd;
	struct rtentry *rt;
	struct sockaddr *sa;
{
	if (rt) {
		rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */
		/*
		 * For optimal performance, the send and receive buffers
		 * should be at least twice the MTU plus a little more for
		 * overhead.
		 */
		rt->rt_rmx.rmx_recvpipe = 
			rt->rt_rmx.rmx_sendpipe = 3 * DUMMYMTU;
	}
}

/*
 * Process an ioctl request.
 */
/* ARGSUSED */
static int
dummyioctl(ifp, cmd, data)
	register struct ifnet *ifp;
	u_long cmd;
	caddr_t data;
{
	register struct ifaddr *ifa;
	register struct ifreq *ifr = (struct ifreq *)data;
	register int error = 0;

	switch (cmd) {

	case SIOCSIFADDR:
		ifnet_set_flags(ifp, IFF_UP | IFF_RUNNING, IFF_UP | IFF_RUNNING);
		ifa = (struct ifaddr *)data;
		ifa->ifa_rtrequest = dummyrtrequest;
		/*
		 * Everything else is done at a higher level.
		 */
		break;

	case SIOCADDMULTI:
	case SIOCDELMULTI:
		if (ifr == 0) {
			error = EAFNOSUPPORT;		/* XXX */
			break;
		}
		switch (ifr->ifr_addr.sa_family) {

#if INET
		case AF_INET:
			break;
#endif
#if INET6
		case AF_INET6:
			break;
#endif

		default:
			error = EAFNOSUPPORT;
			break;
		}
		break;

	case SIOCSIFMTU:
		ifp->if_mtu = ifr->ifr_mtu;
		break;

	case SIOCSIFFLAGS:
		break;

	default:
		error = EINVAL;
	}
	return (error);
}
#endif /* NDUMMY > 0 */