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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.
* 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
* $FreeBSD$
*/
/*
* 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_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_if; /* must be first */
LIST_ENTRY(disc_softc) sc_list;
};
static int discoutput(struct ifnet *, struct mbuf *,
struct sockaddr *, struct rtentry *);
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);
static void disc_clone_destroy(struct ifnet *);
static MALLOC_DEFINE(M_DISC, DISCNAME, "Discard interface");
static LIST_HEAD(, disc_softc) disc_softc_list;
static struct if_clone disc_cloner = IF_CLONE_INITIALIZER(DISCNAME,
disc_clone_create, disc_clone_destroy, 0, IF_MAXUNIT);
static int
disc_clone_create(struct if_clone *ifc, int unit)
{
struct ifnet *ifp;
struct disc_softc *sc;
sc = malloc(sizeof(struct disc_softc), M_DISC, M_WAITOK);
bzero(sc, sizeof(struct disc_softc));
ifp = &sc->sc_if;
ifp->if_softc = sc;
ifp->if_name = DISCNAME;
ifp->if_unit = unit;
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;
ifp->if_snd.ifq_maxlen = 20;
if_attach(ifp);
bpfattach(ifp, DLT_NULL, sizeof(u_int));
LIST_INSERT_HEAD(&disc_softc_list, sc, sc_list);
return (0);
}
static void
disc_clone_destroy(struct ifnet *ifp)
{
struct disc_softc *sc;
sc = ifp->if_softc;
LIST_REMOVE(sc, sc_list);
bpfdetach(ifp);
if_detach(ifp);
free(sc, M_DISC);
}
static int
disc_modevent(module_t mod, int type, void *data)
{
switch (type) {
case MOD_LOAD:
LIST_INIT(&disc_softc_list);
if_clone_attach(&disc_cloner);
break;
case MOD_UNLOAD:
if_clone_detach(&disc_cloner);
while (!LIST_EMPTY(&disc_softc_list))
disc_clone_destroy(
&LIST_FIRST(&disc_softc_list)->sc_if);
break;
}
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 rtentry *rt)
{
M_ASSERTPKTHDR(m);
/* 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 *)⁡
BPF_MTAP(ifp, &m0);
}
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)
{
if (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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