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/*-
* 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.
* 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
* $FreeBSD$
*/
/*
* 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/malloc.h>
#include <sys/module.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <net/if.h>
#include <net/if_clone.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/bpf.h>
#include "opt_inet.h"
#include "opt_inet6.h"
#ifdef TINY_DSMTU
#define DSMTU (1024+512)
#else
#define DSMTU 65532
#endif
#define DISCNAME "disc"
struct disc_softc {
struct ifnet *sc_ifp;
};
static int discoutput(struct ifnet *, struct mbuf *,
struct sockaddr *, struct route *);
static void discrtrequest(int, struct rtentry *, struct rt_addrinfo *);
static int discioctl(struct ifnet *, u_long, caddr_t);
static int disc_clone_create(struct if_clone *, int, caddr_t);
static void disc_clone_destroy(struct ifnet *);
static MALLOC_DEFINE(M_DISC, DISCNAME, "Discard interface");
IFC_SIMPLE_DECLARE(disc, 0);
static int
disc_clone_create(struct if_clone *ifc, int unit, caddr_t params)
{
struct ifnet *ifp;
struct disc_softc *sc;
sc = malloc(sizeof(struct disc_softc), M_DISC, M_WAITOK | M_ZERO);
ifp = sc->sc_ifp = if_alloc(IFT_LOOP);
if (ifp == NULL) {
free(sc, M_DISC);
return (ENOSPC);
}
ifp->if_softc = sc;
if_initname(ifp, ifc->ifc_name, unit);
ifp->if_mtu = DSMTU;
/*
* IFF_LOOPBACK should not be removed from disc's flags because
* it controls what PF-specific routes are magically added when
* a network address is assigned to the interface. Things just
* won't work as intended w/o such routes because the output
* interface selection for a packet is totally route-driven.
* A valid alternative to IFF_LOOPBACK can be IFF_BROADCAST or
* IFF_POINTOPOINT, but it would result in different properties
* of the interface.
*/
ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
ifp->if_drv_flags = IFF_DRV_RUNNING;
ifp->if_ioctl = discioctl;
ifp->if_output = discoutput;
ifp->if_hdrlen = 0;
ifp->if_addrlen = 0;
ifp->if_snd.ifq_maxlen = 20;
if_attach(ifp);
bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
return (0);
}
static void
disc_clone_destroy(struct ifnet *ifp)
{
struct disc_softc *sc;
sc = ifp->if_softc;
bpfdetach(ifp);
if_detach(ifp);
if_free(ifp);
free(sc, M_DISC);
}
static int
disc_modevent(module_t mod, int type, void *data)
{
switch (type) {
case MOD_LOAD:
if_clone_attach(&disc_cloner);
break;
case MOD_UNLOAD:
if_clone_detach(&disc_cloner);
break;
default:
return (EOPNOTSUPP);
}
return (0);
}
static moduledata_t disc_mod = {
"if_disc",
disc_modevent,
NULL
};
DECLARE_MODULE(if_disc, disc_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
static int
discoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
struct route *ro)
{
u_int32_t af;
M_ASSERTPKTHDR(m);
/* BPF writes need to be handled specially. */
if (dst->sa_family == AF_UNSPEC) {
bcopy(dst->sa_data, &af, sizeof(af));
dst->sa_family = af;
}
if (bpf_peers_present(ifp->if_bpf)) {
u_int af = dst->sa_family;
bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
}
m->m_pkthdr.rcvif = ifp;
ifp->if_opackets++;
ifp->if_obytes += m->m_pkthdr.len;
m_freem(m);
return (0);
}
/* ARGSUSED */
static void
discrtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info)
{
RT_LOCK_ASSERT(rt);
rt->rt_rmx.rmx_mtu = DSMTU;
}
/*
* Process an ioctl request.
*/
static int
discioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
struct ifaddr *ifa;
struct ifreq *ifr = (struct ifreq *)data;
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
#ifdef INET6
case AF_INET6:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
case SIOCSIFMTU:
ifp->if_mtu = ifr->ifr_mtu;
break;
default:
error = EINVAL;
}
return (error);
}
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