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mirror of https://git.FreeBSD.org/src.git synced 2024-12-23 11:18:54 +00:00
freebsd/sys/net/if_tun.c
Poul-Henning Kamp 083019ba97 Don't us an array[1], it just hides where '&' isn't used right.
Be consistent about functions being static.

Verified by:	md5 hash of generated .o file.
2002-10-20 20:53:42 +00:00

836 lines
19 KiB
C

/* $NetBSD: if_tun.c,v 1.14 1994/06/29 06:36:25 cgd Exp $ */
/*
* Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk>
* Nottingham University 1987.
*
* This source may be freely distributed, however I would be interested
* in any changes that are made.
*
* This driver takes packets off the IP i/f and hands them up to a
* user process to have its wicked way with. This driver has it's
* roots in a similar driver written by Phil Cockcroft (formerly) at
* UCL. This driver is based much more on read/write/poll mode of
* operation though.
*
* $FreeBSD$
*/
#include "opt_inet.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/mac.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/socket.h>
#include <sys/filio.h>
#include <sys/sockio.h>
#include <sys/ttycom.h>
#include <sys/poll.h>
#include <sys/signalvar.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/conf.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <machine/bus.h> /* XXX Shouldn't really be required ! */
#include <sys/rman.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/intrq.h>
#ifdef INET
#include <netinet/in.h>
#endif
#include <net/bpf.h>
#include <net/if_tunvar.h>
#include <net/if_tun.h>
#define TUNDEBUG if (tundebug) printf
#define TUNNAME "tun"
#define TUN_MAXUNIT 0x7fff /* ifp->if_unit is only 15 bits */
static MALLOC_DEFINE(M_TUN, TUNNAME, "Tunnel Interface");
static int tundebug = 0;
static struct tun_softc *tunhead = NULL;
static struct rman tununits;
static udev_t tunbasedev = NOUDEV;
SYSCTL_INT(_debug, OID_AUTO, if_tun_debug, CTLFLAG_RW, &tundebug, 0, "");
static void tunclone(void *arg, char *name, int namelen, dev_t *dev);
static void tuncreate(dev_t dev);
static int tunifioctl(struct ifnet *, u_long, caddr_t);
static int tuninit(struct ifnet *);
static int tunmodevent(module_t, int, void *);
static int tunoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *rt);
static void tunstart(struct ifnet *);
static d_open_t tunopen;
static d_close_t tunclose;
static d_read_t tunread;
static d_write_t tunwrite;
static d_ioctl_t tunioctl;
static d_poll_t tunpoll;
#define CDEV_MAJOR 52
static struct cdevsw tun_cdevsw = {
/* open */ tunopen,
/* close */ tunclose,
/* read */ tunread,
/* write */ tunwrite,
/* ioctl */ tunioctl,
/* poll */ tunpoll,
/* mmap */ nommap,
/* strategy */ nostrategy,
/* name */ TUNNAME,
/* maj */ CDEV_MAJOR,
/* dump */ nodump,
/* psize */ nopsize,
/* flags */ 0,
};
static void
tunclone(void *arg, char *name, int namelen, dev_t *dev)
{
struct resource *r;
int err;
int u;
if (*dev != NODEV)
return;
if (strcmp(name, TUNNAME) == 0) {
r = rman_reserve_resource(&tununits, 0, TUN_MAXUNIT, 1,
RF_ALLOCATED | RF_ACTIVE, NULL);
u = rman_get_start(r);
err = rman_release_resource(r);
KASSERT(err == 0, ("Unexpected failure releasing resource"));
*dev = makedev(CDEV_MAJOR, unit2minor(u));
if ((*dev)->si_flags & SI_NAMED)
return; /* Already make_dev()d */
} else if (dev_stdclone(name, NULL, TUNNAME, &u) != 1)
return; /* Don't recognise the name */
*dev = make_dev(&tun_cdevsw, unit2minor(u),
UID_ROOT, GID_WHEEL, 0600, "tun%d", u);
/*
* All devices depend on tunbasedev so that we can simply
* destroy_dev() this device at module unload time to get
* rid of all our make_dev()d resources.
*/
if (tunbasedev == NOUDEV)
tunbasedev = (*dev)->si_udev;
else {
(*dev)->si_flags |= SI_CHEAPCLONE;
dev_depends(udev2dev(tunbasedev, 0), *dev);
}
}
static int
tunmodevent(module_t mod, int type, void *data)
{
static eventhandler_tag tag;
struct tun_softc *tp;
dev_t dev;
int err;
switch (type) {
case MOD_LOAD:
tag = EVENTHANDLER_REGISTER(dev_clone, tunclone, 0, 1000);
if (tag == NULL)
return (ENOMEM);
if (!devfs_present) {
err = cdevsw_add(&tun_cdevsw);
if (err != 0) {
EVENTHANDLER_DEREGISTER(dev_clone, tag);
return (err);
}
}
tununits.rm_type = RMAN_ARRAY;
tununits.rm_descr = "open if_tun units";
err = rman_init(&tununits);
if (err != 0) {
cdevsw_remove(&tun_cdevsw);
EVENTHANDLER_DEREGISTER(dev_clone, tag);
return (err);
}
err = rman_manage_region(&tununits, 0, TUN_MAXUNIT);
if (err != 0) {
printf("%s: tununits: rman_manage_region: Failed %d\n",
TUNNAME, err);
rman_fini(&tununits);
cdevsw_remove(&tun_cdevsw);
EVENTHANDLER_DEREGISTER(dev_clone, tag);
return (err);
}
break;
case MOD_UNLOAD:
err = rman_fini(&tununits);
if (err != 0)
return (err);
EVENTHANDLER_DEREGISTER(dev_clone, tag);
while (tunhead != NULL) {
KASSERT((tunhead->tun_flags & TUN_OPEN) == 0,
("tununits is out of sync - unit %d",
tunhead->tun_if.if_unit));
tp = tunhead;
dev = makedev(tun_cdevsw.d_maj,
unit2minor(tp->tun_if.if_unit));
KASSERT(dev->si_drv1 == tp, ("Bad makedev result"));
tunhead = tp->next;
bpfdetach(&tp->tun_if);
if_detach(&tp->tun_if);
KASSERT(dev->si_flags & SI_NAMED, ("Missing make_dev"));
free(tp, M_TUN);
}
/*
* Destroying tunbasedev results in all of our make_dev()s
* conveniently going away.
*/
if (tunbasedev != NOUDEV)
destroy_dev(udev2dev(tunbasedev, 0));
if (!devfs_present)
cdevsw_remove(&tun_cdevsw);
break;
}
return 0;
}
static moduledata_t tun_mod = {
"if_tun",
tunmodevent,
0
};
DECLARE_MODULE(if_tun, tun_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
static void
tunstart(struct ifnet *ifp)
{
struct tun_softc *tp = ifp->if_softc;
if (tp->tun_flags & TUN_RWAIT) {
tp->tun_flags &= ~TUN_RWAIT;
wakeup((caddr_t)tp);
}
if (tp->tun_flags & TUN_ASYNC && tp->tun_sigio)
pgsigio(&tp->tun_sigio, SIGIO, 0);
selwakeup(&tp->tun_rsel);
}
static void
tuncreate(dev_t dev)
{
struct tun_softc *sc;
struct ifnet *ifp;
if (!(dev->si_flags & SI_NAMED))
dev = make_dev(&tun_cdevsw, minor(dev),
UID_UUCP, GID_DIALER, 0600, "tun%d", dev2unit(dev));
MALLOC(sc, struct tun_softc *, sizeof(*sc), M_TUN, M_WAITOK | M_ZERO);
sc->tun_flags = TUN_INITED;
sc->next = tunhead;
tunhead = sc;
ifp = &sc->tun_if;
ifp->if_unit = dev2unit(dev);
ifp->if_name = TUNNAME;
ifp->if_mtu = TUNMTU;
ifp->if_ioctl = tunifioctl;
ifp->if_output = tunoutput;
ifp->if_start = tunstart;
ifp->if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
ifp->if_type = IFT_PPP;
ifp->if_snd.ifq_maxlen = ifqmaxlen;
ifp->if_softc = sc;
if_attach(ifp);
bpfattach(ifp, DLT_NULL, sizeof(u_int));
dev->si_drv1 = sc;
}
static int
tunopen(dev_t dev, int flag, int mode, struct thread *td)
{
struct resource *r;
struct ifnet *ifp;
struct tun_softc *tp;
int unit;
unit = dev2unit(dev);
if (unit > TUN_MAXUNIT)
return (ENXIO);
r = rman_reserve_resource(&tununits, unit, unit, 1,
RF_ALLOCATED | RF_ACTIVE, NULL);
if (r == NULL)
return (EBUSY);
dev->si_flags &= ~SI_CHEAPCLONE;
tp = dev->si_drv1;
if (!tp) {
tuncreate(dev);
tp = dev->si_drv1;
}
KASSERT(!(tp->tun_flags & TUN_OPEN), ("Resource & flags out-of-sync"));
tp->r_unit = r;
tp->tun_pid = td->td_proc->p_pid;
ifp = &tp->tun_if;
tp->tun_flags |= TUN_OPEN;
TUNDEBUG("%s%d: open\n", ifp->if_name, ifp->if_unit);
return (0);
}
/*
* tunclose - close the device - mark i/f down & delete
* routing info
*/
static int
tunclose(dev_t dev, int foo, int bar, struct thread *td)
{
struct tun_softc *tp;
struct ifnet *ifp;
int s;
int err;
tp = dev->si_drv1;
ifp = &tp->tun_if;
KASSERT(tp->r_unit, ("Unit %d not marked open", ifp->if_unit));
tp->tun_flags &= ~TUN_OPEN;
tp->tun_pid = 0;
/*
* junk all pending output
*/
IF_DRAIN(&ifp->if_snd);
if (ifp->if_flags & IFF_UP) {
s = splimp();
if_down(ifp);
splx(s);
}
if (ifp->if_flags & IFF_RUNNING) {
register struct ifaddr *ifa;
s = splimp();
/* find internet addresses and delete routes */
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
if (ifa->ifa_addr->sa_family == AF_INET)
rtinit(ifa, (int)RTM_DELETE,
tp->tun_flags & TUN_DSTADDR ? RTF_HOST : 0);
ifp->if_flags &= ~IFF_RUNNING;
splx(s);
}
funsetown(&tp->tun_sigio);
selwakeup(&tp->tun_rsel);
TUNDEBUG ("%s%d: closed\n", ifp->if_name, ifp->if_unit);
err = rman_release_resource(tp->r_unit);
KASSERT(err == 0, ("Unit %d failed to release", ifp->if_unit));
return (0);
}
static int
tuninit(struct ifnet *ifp)
{
struct tun_softc *tp = ifp->if_softc;
register struct ifaddr *ifa;
int error = 0;
TUNDEBUG("%s%d: tuninit\n", ifp->if_name, ifp->if_unit);
ifp->if_flags |= IFF_UP | IFF_RUNNING;
getmicrotime(&ifp->if_lastchange);
for (ifa = TAILQ_FIRST(&ifp->if_addrhead); ifa;
ifa = TAILQ_NEXT(ifa, ifa_link)) {
if (ifa->ifa_addr == NULL)
error = EFAULT;
/* XXX: Should maybe return straight off? */
else {
#ifdef INET
if (ifa->ifa_addr->sa_family == AF_INET) {
struct sockaddr_in *si;
si = (struct sockaddr_in *)ifa->ifa_addr;
if (si->sin_addr.s_addr)
tp->tun_flags |= TUN_IASET;
si = (struct sockaddr_in *)ifa->ifa_dstaddr;
if (si && si->sin_addr.s_addr)
tp->tun_flags |= TUN_DSTADDR;
}
#endif
}
}
return (error);
}
/*
* Process an ioctl request.
*/
static int
tunifioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
struct ifreq *ifr = (struct ifreq *)data;
struct tun_softc *tp = ifp->if_softc;
struct ifstat *ifs;
int error = 0, s;
s = splimp();
switch(cmd) {
case SIOCGIFSTATUS:
ifs = (struct ifstat *)data;
if (tp->tun_pid)
sprintf(ifs->ascii + strlen(ifs->ascii),
"\tOpened by PID %d\n", tp->tun_pid);
break;
case SIOCSIFADDR:
error = tuninit(ifp);
TUNDEBUG("%s%d: address set, error=%d\n",
ifp->if_name, ifp->if_unit, error);
break;
case SIOCSIFDSTADDR:
error = tuninit(ifp);
TUNDEBUG("%s%d: destination address set, error=%d\n",
ifp->if_name, ifp->if_unit, error);
break;
case SIOCSIFMTU:
ifp->if_mtu = ifr->ifr_mtu;
TUNDEBUG("%s%d: mtu set\n", ifp->if_name, ifp->if_unit);
break;
case SIOCSIFFLAGS:
case SIOCADDMULTI:
case SIOCDELMULTI:
break;
default:
error = EINVAL;
}
splx(s);
return (error);
}
/*
* tunoutput - queue packets from higher level ready to put out.
*/
static int
tunoutput(
struct ifnet *ifp,
struct mbuf *m0,
struct sockaddr *dst,
struct rtentry *rt)
{
struct tun_softc *tp = ifp->if_softc;
#ifdef MAC
int error;
#endif
TUNDEBUG ("%s%d: tunoutput\n", ifp->if_name, ifp->if_unit);
#ifdef MAC
error = mac_check_ifnet_transmit(ifp, m0);
if (error) {
m_freem(m0);
return (error);
}
#endif
if ((tp->tun_flags & TUN_READY) != TUN_READY) {
TUNDEBUG ("%s%d: not ready 0%o\n", ifp->if_name,
ifp->if_unit, tp->tun_flags);
m_freem (m0);
return (EHOSTDOWN);
}
/* BPF write needs to be handled specially */
if (dst->sa_family == AF_UNSPEC) {
dst->sa_family = *(mtod(m0, int *));
m0->m_len -= sizeof(int);
m0->m_pkthdr.len -= sizeof(int);
m0->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 to it).
*/
struct mbuf m;
uint32_t af = dst->sa_family;
m.m_next = m0;
m.m_len = 4;
m.m_data = (char *)&af;
bpf_mtap(ifp, &m);
}
/* prepend sockaddr? this may abort if the mbuf allocation fails */
if (tp->tun_flags & TUN_LMODE) {
/* allocate space for sockaddr */
M_PREPEND(m0, dst->sa_len, M_DONTWAIT);
/* if allocation failed drop packet */
if (m0 == NULL) {
ifp->if_iqdrops++;
ifp->if_oerrors++;
return (ENOBUFS);
} else {
bcopy(dst, m0->m_data, dst->sa_len);
}
}
if (tp->tun_flags & TUN_IFHEAD) {
/* Prepend the address family */
M_PREPEND(m0, 4, M_DONTWAIT);
/* if allocation failed drop packet */
if (m0 == NULL) {
ifp->if_iqdrops++;
ifp->if_oerrors++;
return (ENOBUFS);
} else
*(u_int32_t *)m0->m_data = htonl(dst->sa_family);
} else {
#ifdef INET
if (dst->sa_family != AF_INET)
#endif
{
m_freem(m0);
return (EAFNOSUPPORT);
}
}
if (! IF_HANDOFF(&ifp->if_snd, m0, ifp)) {
ifp->if_collisions++;
return (ENOBUFS);
}
ifp->if_opackets++;
return (0);
}
/*
* the cdevsw interface is now pretty minimal.
*/
static int
tunioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct thread *td)
{
int s;
int error;
struct tun_softc *tp = dev->si_drv1;
struct tuninfo *tunp;
switch (cmd) {
case TUNSIFINFO:
tunp = (struct tuninfo *)data;
if (tunp->mtu < IF_MINMTU)
return (EINVAL);
if (tp->tun_if.if_mtu != tunp->mtu
&& (error = suser(td)) != 0)
return (error);
tp->tun_if.if_mtu = tunp->mtu;
tp->tun_if.if_type = tunp->type;
tp->tun_if.if_baudrate = tunp->baudrate;
break;
case TUNGIFINFO:
tunp = (struct tuninfo *)data;
tunp->mtu = tp->tun_if.if_mtu;
tunp->type = tp->tun_if.if_type;
tunp->baudrate = tp->tun_if.if_baudrate;
break;
case TUNSDEBUG:
tundebug = *(int *)data;
break;
case TUNGDEBUG:
*(int *)data = tundebug;
break;
case TUNSLMODE:
if (*(int *)data) {
tp->tun_flags |= TUN_LMODE;
tp->tun_flags &= ~TUN_IFHEAD;
} else
tp->tun_flags &= ~TUN_LMODE;
break;
case TUNSIFHEAD:
if (*(int *)data) {
tp->tun_flags |= TUN_IFHEAD;
tp->tun_flags &= ~TUN_LMODE;
} else
tp->tun_flags &= ~TUN_IFHEAD;
break;
case TUNGIFHEAD:
*(int *)data = (tp->tun_flags & TUN_IFHEAD) ? 1 : 0;
break;
case TUNSIFMODE:
/* deny this if UP */
if (tp->tun_if.if_flags & IFF_UP)
return(EBUSY);
switch (*(int *)data & ~IFF_MULTICAST) {
case IFF_POINTOPOINT:
case IFF_BROADCAST:
tp->tun_if.if_flags &=
~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST);
tp->tun_if.if_flags |= *(int *)data;
break;
default:
return(EINVAL);
}
break;
case TUNSIFPID:
tp->tun_pid = curthread->td_proc->p_pid;
break;
case FIONBIO:
break;
case FIOASYNC:
if (*(int *)data)
tp->tun_flags |= TUN_ASYNC;
else
tp->tun_flags &= ~TUN_ASYNC;
break;
case FIONREAD:
s = splimp();
if (tp->tun_if.if_snd.ifq_head) {
struct mbuf *mb = tp->tun_if.if_snd.ifq_head;
for( *(int *)data = 0; mb != 0; mb = mb->m_next)
*(int *)data += mb->m_len;
} else
*(int *)data = 0;
splx(s);
break;
case FIOSETOWN:
return (fsetown(*(int *)data, &tp->tun_sigio));
case FIOGETOWN:
*(int *)data = fgetown(&tp->tun_sigio);
return (0);
/* This is deprecated, FIOSETOWN should be used instead. */
case TIOCSPGRP:
return (fsetown(-(*(int *)data), &tp->tun_sigio));
/* This is deprecated, FIOGETOWN should be used instead. */
case TIOCGPGRP:
*(int *)data = -fgetown(&tp->tun_sigio);
return (0);
default:
return (ENOTTY);
}
return (0);
}
/*
* The cdevsw read interface - reads a packet at a time, or at
* least as much of a packet as can be read.
*/
static int
tunread(dev_t dev, struct uio *uio, int flag)
{
struct tun_softc *tp = dev->si_drv1;
struct ifnet *ifp = &tp->tun_if;
struct mbuf *m;
int error=0, len, s;
TUNDEBUG ("%s%d: read\n", ifp->if_name, ifp->if_unit);
if ((tp->tun_flags & TUN_READY) != TUN_READY) {
TUNDEBUG ("%s%d: not ready 0%o\n", ifp->if_name,
ifp->if_unit, tp->tun_flags);
return (EHOSTDOWN);
}
tp->tun_flags &= ~TUN_RWAIT;
s = splimp();
do {
IF_DEQUEUE(&ifp->if_snd, m);
if (m == NULL) {
if (flag & IO_NDELAY) {
splx(s);
return (EWOULDBLOCK);
}
tp->tun_flags |= TUN_RWAIT;
if((error = tsleep((caddr_t)tp, PCATCH | (PZERO + 1),
"tunread", 0)) != 0) {
splx(s);
return (error);
}
}
} while (m == NULL);
splx(s);
while (m && uio->uio_resid > 0 && error == 0) {
len = min(uio->uio_resid, m->m_len);
if (len != 0)
error = uiomove(mtod(m, caddr_t), len, uio);
m = m_free(m);
}
if (m) {
TUNDEBUG("%s%d: Dropping mbuf\n", ifp->if_name, ifp->if_unit);
m_freem(m);
}
return (error);
}
/*
* the cdevsw write interface - an atomic write is a packet - or else!
*/
static int
tunwrite(dev_t dev, struct uio *uio, int flag)
{
struct tun_softc *tp = dev->si_drv1;
struct ifnet *ifp = &tp->tun_if;
struct mbuf *top, **mp, *m;
int error=0, tlen, mlen;
uint32_t family;
TUNDEBUG("%s%d: tunwrite\n", ifp->if_name, ifp->if_unit);
if (uio->uio_resid == 0)
return (0);
if (uio->uio_resid < 0 || uio->uio_resid > TUNMRU) {
TUNDEBUG("%s%d: len=%d!\n", ifp->if_name, ifp->if_unit,
uio->uio_resid);
return (EIO);
}
tlen = uio->uio_resid;
/* get a header mbuf */
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL)
return (ENOBUFS);
mlen = MHLEN;
top = 0;
mp = &top;
while (error == 0 && uio->uio_resid > 0) {
m->m_len = min(mlen, uio->uio_resid);
error = uiomove(mtod (m, caddr_t), m->m_len, uio);
*mp = m;
mp = &m->m_next;
if (uio->uio_resid > 0) {
MGET (m, M_DONTWAIT, MT_DATA);
if (m == 0) {
error = ENOBUFS;
break;
}
mlen = MLEN;
}
}
if (error) {
if (top)
m_freem (top);
ifp->if_ierrors++;
return (error);
}
top->m_pkthdr.len = tlen;
top->m_pkthdr.rcvif = ifp;
#ifdef MAC
mac_create_mbuf_from_ifnet(ifp, top);
#endif
if (ifp->if_bpf) {
if (tp->tun_flags & TUN_IFHEAD) {
/*
* Conveniently, we already have a 4-byte address
* family prepended to our packet !
* Inconveniently, it's in the wrong byte order !
*/
if ((top = m_pullup(top, sizeof(family))) == NULL)
return (ENOBUFS);
*mtod(top, u_int32_t *) =
ntohl(*mtod(top, u_int32_t *));
bpf_mtap(ifp, top);
*mtod(top, u_int32_t *) =
htonl(*mtod(top, u_int32_t *));
} else {
/*
* 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 to it).
*/
struct mbuf m;
uint32_t af = AF_INET;
m.m_next = top;
m.m_len = 4;
m.m_data = (char *)&af;
bpf_mtap(ifp, &m);
}
}
if (tp->tun_flags & TUN_IFHEAD) {
if (top->m_len < sizeof(family) &&
(top = m_pullup(top, sizeof(family))) == NULL)
return (ENOBUFS);
family = ntohl(*mtod(top, u_int32_t *));
m_adj(top, sizeof(family));
} else
family = AF_INET;
ifp->if_ibytes += top->m_pkthdr.len;
ifp->if_ipackets++;
return (family_enqueue(family, top));
}
/*
* tunpoll - the poll interface, this is only useful on reads
* really. The write detect always returns true, write never blocks
* anyway, it either accepts the packet or drops it.
*/
static int
tunpoll(dev_t dev, int events, struct thread *td)
{
int s;
struct tun_softc *tp = dev->si_drv1;
struct ifnet *ifp = &tp->tun_if;
int revents = 0;
s = splimp();
TUNDEBUG("%s%d: tunpoll\n", ifp->if_name, ifp->if_unit);
if (events & (POLLIN | POLLRDNORM)) {
if (ifp->if_snd.ifq_len > 0) {
TUNDEBUG("%s%d: tunpoll q=%d\n", ifp->if_name,
ifp->if_unit, ifp->if_snd.ifq_len);
revents |= events & (POLLIN | POLLRDNORM);
} else {
TUNDEBUG("%s%d: tunpoll waiting\n", ifp->if_name,
ifp->if_unit);
selrecord(td, &tp->tun_rsel);
}
}
if (events & (POLLOUT | POLLWRNORM))
revents |= events & (POLLOUT | POLLWRNORM);
splx(s);
return (revents);
}