freebsd-skq/sys/net/if_loop.c
Garrett Wollman 963e4c2a50 Fix BPf to generate a header mbuf for writes.
Fix loopback and discard interfaces to understand BPF writes.
(These two from Bill Fenner to fix PR 512.)

Move ifpromisc() from bpf.c to if.c as suggested by comment in BPF.
Send a notice to the log when promiscuous mode is enabled.
1995-09-22 17:57:48 +00:00

272 lines
6.1 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.
*
* @(#)if_loop.c 8.1 (Berkeley) 6/10/93
* $Id: if_loop.c,v 1.12 1995/09/09 18:10:22 davidg Exp $
*/
/*
* Loopback interface driver for protocol testing and timing.
*/
#include "loop.h"
#if NLOOP > 0
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <machine/cpu.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/bpf.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#endif
#ifdef NS
#include <netns/ns.h>
#include <netns/ns_if.h>
#endif
#ifdef ISO
#include <netiso/iso.h>
#include <netiso/iso_var.h>
#endif
#include "bpfilter.h"
static void loopattach __P((void *));
PSEUDO_SET(loopattach, if_loop);
#ifdef TINY_LOMTU
#define LOMTU (1024+512)
#else
#define LOMTU 16384
#endif
struct ifnet loif[NLOOP];
/* ARGSUSED */
static void
loopattach(udata)
void *udata;
{
register struct ifnet *ifp;
register int i = 0;
for (ifp = loif; i < NLOOP; ifp++) {
ifp->if_name = "lo";
ifp->if_next = NULL;
ifp->if_unit = i++;
ifp->if_mtu = LOMTU;
ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
ifp->if_ioctl = loioctl;
ifp->if_output = looutput;
ifp->if_type = IFT_LOOP;
ifp->if_hdrlen = 0;
ifp->if_addrlen = 0;
if_attach(ifp);
#if NBPFILTER > 0
bpfattach(&ifp->if_bpf, ifp, DLT_NULL, sizeof(u_int));
#endif
}
}
int
looutput(ifp, m, dst, rt)
struct ifnet *ifp;
register struct mbuf *m;
struct sockaddr *dst;
register struct rtentry *rt;
{
int s, isr;
register struct ifqueue *ifq = 0;
if ((m->m_flags & M_PKTHDR) == 0)
panic("looutput no HDR");
ifp->if_lastchange = time;
#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;
bpf_mtap(ifp->if_bpf, &m0);
}
#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;
switch (dst->sa_family) {
#ifdef INET
case AF_INET:
ifq = &ipintrq;
isr = NETISR_IP;
break;
#endif
#ifdef NS
case AF_NS:
ifq = &nsintrq;
isr = NETISR_NS;
break;
#endif
#ifdef ISO
case AF_ISO:
ifq = &clnlintrq;
isr = NETISR_ISO;
break;
#endif
default:
printf("lo%d: can't handle af%d\n", ifp->if_unit,
dst->sa_family);
m_freem(m);
return (EAFNOSUPPORT);
}
s = splimp();
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
m_freem(m);
splx(s);
return (ENOBUFS);
}
IF_ENQUEUE(ifq, m);
schednetisr(isr);
ifp->if_ipackets++;
ifp->if_ibytes += m->m_pkthdr.len;
splx(s);
return (0);
}
/* ARGSUSED */
void
lortrequest(cmd, rt, sa)
int cmd;
struct rtentry *rt;
struct sockaddr *sa;
{
if (rt)
rt->rt_rmx.rmx_mtu = LOMTU;
}
/*
* Process an ioctl request.
*/
/* ARGSUSED */
int
loioctl(ifp, cmd, data)
register struct ifnet *ifp;
int 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_addr->sa_family == AF_ISO)
ifa->ifa_rtrequest = lortrequest;
/*
* 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);
}
#endif /* NLOOP > 0 */