freebsd-skq/sys/net/if_disc.c
1999-07-06 19:23:32 +00:00

203 lines
5.0 KiB
C

/*
* 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.
*
* From: @(#)if_loop.c 8.1 (Berkeley) 6/10/93
* $Id: if_disc.c,v 1.21 1998/12/14 01:59:16 eivind Exp $
*/
/*
* Discard interface driver for protocol testing and timing.
* (Based on the loopback.)
*/
#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 <net/if.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/bpf.h>
#include "bpf.h"
#include "opt_inet.h"
#ifdef TINY_DSMTU
#define DSMTU (1024+512)
#else
#define DSMTU 65532
#endif
static void discattach __P((void *dummy));
PSEUDO_SET(discattach, if_disc);
static struct ifnet discif;
static int discoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *);
static void discrtrequest(int cmd, struct rtentry *rt, struct sockaddr *sa);
static int discioctl(struct ifnet *, u_long, caddr_t);
/* ARGSUSED */
static void
discattach(dummy)
void *dummy;
{
register struct ifnet *ifp = &discif;
ifp->if_name = "ds";
ifp->if_mtu = DSMTU;
ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
ifp->if_ioctl = discioctl;
ifp->if_output = discoutput;
ifp->if_type = IFT_LOOP;
ifp->if_hdrlen = 0;
ifp->if_addrlen = 0;
if_attach(ifp);
#if NBPF > 0
bpfattach(ifp, DLT_NULL, sizeof(u_int));
#endif
}
static int
discoutput(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("discoutput no HDR");
#if NBPF > 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 (discif.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;
bpf_mtap(&discif, &m0);
}
#endif
m->m_pkthdr.rcvif = ifp;
ifp->if_opackets++;
ifp->if_obytes += m->m_pkthdr.len;
m_freem(m);
return 0;
}
/* ARGSUSED */
static void
discrtrequest(cmd, rt, sa)
int cmd;
struct rtentry *rt;
struct sockaddr *sa;
{
if (rt)
rt->rt_rmx.rmx_mtu = DSMTU;
}
/*
* Process an ioctl request.
*/
/* ARGSUSED */
static int
discioctl(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:
ifp->if_flags |= IFF_UP;
ifa = (struct ifaddr *)data;
if (ifa != 0)
ifa->ifa_rtrequest = discrtrequest;
/*
* 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) {
#ifdef INET
case AF_INET:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCSIFMTU:
ifp->if_mtu = ifr->ifr_mtu;
break;
default:
error = EINVAL;
}
return (error);
}