NetBSD/sys/net/if_loop.c
pgoyette dc68f5827a Set the "required modules" to NULL, not to an empty string.
It really doesn't make that much difference to the code, but the output
from modstat(8) is different!  (With an empty string in the MODULE() macro
modstat reports an empty string, but with a NULL in the macro, modstat
prints a '-' just like it does for other "empty" fields.)
2019-04-26 08:38:25 +00:00

534 lines
12 KiB
C

/* $NetBSD: if_loop.c,v 1.107 2019/04/26 08:38:25 pgoyette Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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. Neither the name of the project 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 PROJECT 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 PROJECT 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.
*/
/*
* 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. 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 8.2 (Berkeley) 1/9/95
*/
/*
* Loopback interface driver for protocol testing and timing.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_loop.c,v 1.107 2019/04/26 08:38:25 pgoyette Exp $");
#ifdef _KERNEL_OPT
#include "opt_inet.h"
#include "opt_atalk.h"
#include "opt_mbuftrace.h"
#include "opt_mpls.h"
#include "opt_net_mpsafe.h"
#endif
#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 <sys/device.h>
#include <sys/module.h>
#include <sys/cpu.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/in_offload.h>
#include <netinet/ip.h>
#endif
#ifdef INET6
#ifndef INET
#include <netinet/in.h>
#endif
#include <netinet6/in6_var.h>
#include <netinet6/in6_offload.h>
#include <netinet/ip6.h>
#endif
#ifdef MPLS
#include <netmpls/mpls.h>
#include <netmpls/mpls_var.h>
#endif
#ifdef NETATALK
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#endif
#include <net/bpf.h>
#if defined(LARGE_LOMTU)
#define LOMTU (131072 + MHLEN + MLEN)
#define LOMTU_MAX LOMTU
#else
#define LOMTU (32768 + MHLEN + MLEN)
#define LOMTU_MAX (65536 + MHLEN + MLEN)
#endif
#ifdef ALTQ
static void lostart(struct ifnet *);
#endif
static int loop_clone_create(struct if_clone *, int);
static int loop_clone_destroy(struct ifnet *);
static void loop_rtrequest(int, struct rtentry *, const struct rt_addrinfo *);
static struct if_clone loop_cloner =
IF_CLONE_INITIALIZER("lo", loop_clone_create, loop_clone_destroy);
void
loopattach(int n)
{
#ifndef _MODULE
loop_clone_create(&loop_cloner, 0); /* lo0 always exists */
#endif
}
void
loopinit(void)
{
if (lo0ifp != NULL) /* can happen in rump kernel */
return;
#ifdef _MODULE
loop_clone_create(&loop_cloner, 0); /* lo0 always exists */
#endif
if_clone_attach(&loop_cloner);
}
static int
loopdetach(void)
{
/* no detach for now; we don't allow lo0 to be deleted */
return EBUSY;
}
static int
loop_clone_create(struct if_clone *ifc, int unit)
{
struct ifnet *ifp;
int rv;
ifp = if_alloc(IFT_LOOP);
if_initname(ifp, ifc->ifc_name, unit);
ifp->if_mtu = LOMTU;
ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
ifp->if_extflags = IFEF_NO_LINK_STATE_CHANGE;
#ifdef NET_MPSAFE
ifp->if_extflags |= IFEF_MPSAFE;
#endif
ifp->if_ioctl = loioctl;
ifp->if_output = looutput;
#ifdef ALTQ
ifp->if_start = lostart;
#endif
ifp->if_type = IFT_LOOP;
ifp->if_hdrlen = 0;
ifp->if_addrlen = 0;
ifp->if_dlt = DLT_NULL;
IFQ_SET_READY(&ifp->if_snd);
if (unit == 0)
lo0ifp = ifp;
rv = if_attach(ifp);
if (rv != 0) {
if_free(ifp);
return rv;
}
if_alloc_sadl(ifp);
bpf_attach(ifp, DLT_NULL, sizeof(u_int));
#ifdef MBUFTRACE
ifp->if_mowner = malloc(sizeof(struct mowner), M_DEVBUF,
M_WAITOK | M_ZERO);
strlcpy(ifp->if_mowner->mo_name, ifp->if_xname,
sizeof(ifp->if_mowner->mo_name));
MOWNER_ATTACH(ifp->if_mowner);
#endif
ifp->if_flags |= IFF_RUNNING;
return (0);
}
static int
loop_clone_destroy(struct ifnet *ifp)
{
if (ifp == lo0ifp)
return (EPERM);
ifp->if_flags &= ~IFF_RUNNING;
#ifdef MBUFTRACE
MOWNER_DETACH(ifp->if_mowner);
free(ifp->if_mowner, M_DEVBUF);
#endif
bpf_detach(ifp);
if_detach(ifp);
if_free(ifp);
return (0);
}
int
looutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
const struct rtentry *rt)
{
pktqueue_t *pktq = NULL;
struct ifqueue *ifq = NULL;
int s, isr = -1;
int csum_flags;
int error = 0;
size_t pktlen;
MCLAIM(m, ifp->if_mowner);
KERNEL_LOCK_UNLESS_NET_MPSAFE();
if ((m->m_flags & M_PKTHDR) == 0)
panic("looutput: no header mbuf");
if (ifp->if_flags & IFF_LOOPBACK)
bpf_mtap_af(ifp, dst->sa_family, m, BPF_D_OUT);
m_set_rcvif(m, ifp);
if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
m_freem(m);
error = (rt->rt_flags & RTF_BLACKHOLE ? 0 :
rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
goto out;
}
pktlen = m->m_pkthdr.len;
ifp->if_opackets++;
ifp->if_obytes += pktlen;
#ifdef ALTQ
/*
* ALTQ on the loopback interface is just for debugging. It's
* used only for loopback interfaces, not for a simplex interface.
*/
if ((ALTQ_IS_ENABLED(&ifp->if_snd) || TBR_IS_ENABLED(&ifp->if_snd)) &&
ifp->if_start == lostart) {
/*
* If the queueing discipline needs packet classification,
* do it before prepending the link headers.
*/
IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family);
M_PREPEND(m, sizeof(uint32_t), M_DONTWAIT);
if (m == NULL) {
error = ENOBUFS;
goto out;
}
*(mtod(m, uint32_t *)) = dst->sa_family;
error = if_transmit_lock(ifp, m);
goto out;
}
#endif /* ALTQ */
m_tag_delete_chain(m);
#ifdef MPLS
if (rt != NULL && rt_gettag(rt) != NULL &&
rt_gettag(rt)->sa_family == AF_MPLS &&
(m->m_flags & (M_MCAST | M_BCAST)) == 0) {
union mpls_shim msh;
msh.s_addr = MPLS_GETSADDR(rt);
if (msh.shim.label != MPLS_LABEL_IMPLNULL) {
ifq = &mplsintrq;
isr = NETISR_MPLS;
}
}
if (isr != NETISR_MPLS)
#endif
switch (dst->sa_family) {
#ifdef INET
case AF_INET:
csum_flags = m->m_pkthdr.csum_flags;
KASSERT((csum_flags & ~(M_CSUM_IPv4|M_CSUM_UDPv4)) == 0);
if (csum_flags != 0 && IN_LOOPBACK_NEED_CHECKSUM(csum_flags)) {
in_undefer_cksum(m, 0, csum_flags);
}
m->m_pkthdr.csum_flags = 0;
pktq = ip_pktq;
break;
#endif
#ifdef INET6
case AF_INET6:
csum_flags = m->m_pkthdr.csum_flags;
KASSERT((csum_flags & ~M_CSUM_UDPv6) == 0);
if (csum_flags != 0 &&
IN6_LOOPBACK_NEED_CHECKSUM(csum_flags)) {
in6_undefer_cksum(m, 0, csum_flags);
}
m->m_pkthdr.csum_flags = 0;
m->m_flags |= M_LOOP;
pktq = ip6_pktq;
break;
#endif
#ifdef NETATALK
case AF_APPLETALK:
ifq = &atintrq2;
isr = NETISR_ATALK;
break;
#endif
default:
printf("%s: can't handle af%d\n", ifp->if_xname,
dst->sa_family);
m_freem(m);
error = EAFNOSUPPORT;
goto out;
}
s = splnet();
if (__predict_true(pktq)) {
error = 0;
if (__predict_true(pktq_enqueue(pktq, m, 0))) {
ifp->if_ipackets++;
ifp->if_ibytes += pktlen;
} else {
m_freem(m);
error = ENOBUFS;
}
splx(s);
goto out;
}
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
m_freem(m);
splx(s);
error = ENOBUFS;
goto out;
}
ifp->if_ipackets++;
ifp->if_ibytes += m->m_pkthdr.len;
IF_ENQUEUE(ifq, m);
schednetisr(isr);
splx(s);
out:
KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
return error;
}
#ifdef ALTQ
static void
lostart(struct ifnet *ifp)
{
for (;;) {
pktqueue_t *pktq = NULL;
struct ifqueue *ifq = NULL;
struct mbuf *m;
size_t pktlen;
uint32_t af;
int s, isr = 0;
IFQ_DEQUEUE(&ifp->if_snd, m);
if (m == NULL)
return;
af = *(mtod(m, uint32_t *));
m_adj(m, sizeof(uint32_t));
switch (af) {
#ifdef INET
case AF_INET:
pktq = ip_pktq;
break;
#endif
#ifdef INET6
case AF_INET6:
m->m_flags |= M_LOOP;
pktq = ip6_pktq;
break;
#endif
#ifdef NETATALK
case AF_APPLETALK:
ifq = &atintrq2;
isr = NETISR_ATALK;
break;
#endif
default:
printf("%s: can't handle af%d\n", ifp->if_xname, af);
m_freem(m);
return;
}
pktlen = m->m_pkthdr.len;
s = splnet();
if (__predict_true(pktq)) {
if (__predict_false(pktq_enqueue(pktq, m, 0))) {
m_freem(m);
splx(s);
return;
}
ifp->if_ipackets++;
ifp->if_ibytes += pktlen;
splx(s);
continue;
}
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
splx(s);
m_freem(m);
return;
}
IF_ENQUEUE(ifq, m);
schednetisr(isr);
ifp->if_ipackets++;
ifp->if_ibytes += pktlen;
splx(s);
}
}
#endif /* ALTQ */
/* ARGSUSED */
static void
loop_rtrequest(int cmd, struct rtentry *rt,
const struct rt_addrinfo *info)
{
if (rt)
rt->rt_rmx.rmx_mtu = lo0ifp->if_mtu;
}
/*
* Process an ioctl request.
*/
/* ARGSUSED */
int
loioctl(struct ifnet *ifp, u_long cmd, void *data)
{
struct ifaddr *ifa;
struct ifreq *ifr = data;
int error = 0;
switch (cmd) {
case SIOCINITIFADDR:
ifp->if_flags |= IFF_UP;
ifa = (struct ifaddr *)data;
if (ifa != NULL)
ifa->ifa_rtrequest = loop_rtrequest;
/*
* Everything else is done at a higher level.
*/
break;
case SIOCSIFMTU:
if ((unsigned)ifr->ifr_mtu > LOMTU_MAX)
error = EINVAL;
else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET){
error = 0;
}
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
if (ifr == NULL) {
error = EAFNOSUPPORT; /* XXX */
break;
}
switch (ifreq_getaddr(cmd, ifr)->sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef INET6
case AF_INET6:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
default:
error = ifioctl_common(ifp, cmd, data);
}
return (error);
}
/*
* Module infrastructure
*/
#include "if_module.h"
IF_MODULE(MODULE_CLASS_DRIVER, loop, NULL)