File: [local] / sys / net / if_tun.c (download)
Revision 1.1, Tue Mar 4 16:16:29 2008 UTC (16 years, 6 months ago) by nbrk
Branch point for: MAIN
Initial revision
|
/* $OpenBSD: if_tun.c,v 1.89 2007/06/06 10:04:36 henning Exp $ */
/* $NetBSD: if_tun.c,v 1.24 1996/05/07 02:40:48 thorpej Exp $ */
/*
* Copyright (c) 1988, Julian Onions <Julian.Onions@nexor.co.uk>
* Nottingham University 1987.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/*
* 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 its
* roots in a similar driver written by Phil Cockcroft (formerly) at
* UCL. This driver is based much more on read/write/select mode of
* operation though.
*/
/* #define TUN_DEBUG 9 */
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/syslog.h>
#include <sys/selinfo.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/device.h>
#include <sys/vnode.h>
#include <sys/signalvar.h>
#include <sys/poll.h>
#include <sys/conf.h>
#include <machine/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/ip.h>
#include <netinet/if_ether.h>
#endif
#ifdef NETATALK
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#endif
#include "bpfilter.h"
#if NBPFILTER > 0
#include <net/bpf.h>
#endif
/* for arc4random() */
#include <dev/rndvar.h>
#include <net/if_tun.h>
struct tun_softc {
struct arpcom arpcom; /* ethernet common data */
u_short tun_flags; /* misc flags */
pid_t tun_pgid; /* the process group - if any */
uid_t tun_siguid; /* uid for process that set tun_pgid */
uid_t tun_sigeuid; /* euid for process that set tun_pgid */
struct selinfo tun_rsel; /* read select */
struct selinfo tun_wsel; /* write select (not used) */
int tun_unit;
LIST_ENTRY(tun_softc) tun_list; /* all tunnel interfaces */
#define tun_if arpcom.ac_if
};
#ifdef TUN_DEBUG
int tundebug = TUN_DEBUG;
#define TUNDEBUG(a) (tundebug? printf a : 0)
#else
#define TUNDEBUG(a) /* (tundebug? printf a : 0) */
#endif
/* Only these IFF flags are changeable by TUNSIFINFO */
#define TUN_IFF_FLAGS (IFF_UP|IFF_POINTOPOINT|IFF_MULTICAST|IFF_BROADCAST)
void tunattach(int);
int tunopen(dev_t, int, int, struct proc *);
int tunclose(dev_t, int, int, struct proc *);
int tun_ioctl(struct ifnet *, u_long, caddr_t);
int tun_output(struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *);
int tunioctl(dev_t, u_long, caddr_t, int, struct proc *);
int tunread(dev_t, struct uio *, int);
int tunwrite(dev_t, struct uio *, int);
int tunpoll(dev_t, int, struct proc *);
int tunkqfilter(dev_t, struct knote *);
int tun_clone_create(struct if_clone *, int);
int tun_create(struct if_clone *, int, int);
int tun_clone_destroy(struct ifnet *);
struct tun_softc *tun_lookup(int);
void tun_wakeup(struct tun_softc *);
int tun_switch(struct tun_softc *, int);
static int tuninit(struct tun_softc *);
static void tunstart(struct ifnet *);
int filt_tunread(struct knote *, long);
int filt_tunwrite(struct knote *, long);
void filt_tunrdetach(struct knote *);
void filt_tunwdetach(struct knote *);
struct filterops tunread_filtops =
{ 1, NULL, filt_tunrdetach, filt_tunread};
struct filterops tunwrite_filtops =
{ 1, NULL, filt_tunwdetach, filt_tunwrite};
LIST_HEAD(, tun_softc) tun_softc_list;
struct if_clone tun_cloner =
IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy);
void
tunattach(int n)
{
LIST_INIT(&tun_softc_list);
if_clone_attach(&tun_cloner);
}
int
tun_clone_create(struct if_clone *ifc, int unit)
{
return (tun_create(ifc, unit, 0));
}
int
tun_create(struct if_clone *ifc, int unit, int flags)
{
struct tun_softc *tp;
struct ifnet *ifp;
u_int32_t macaddr_rnd;
int s;
tp = malloc(sizeof(*tp), M_DEVBUF, M_NOWAIT);
if (!tp)
return (ENOMEM);
bzero(tp, sizeof(*tp));
tp->tun_unit = unit;
tp->tun_flags = TUN_INITED|TUN_STAYUP;
/* generate fake MAC address: 00 bd xx xx xx unit_no */
tp->arpcom.ac_enaddr[0] = 0x00;
tp->arpcom.ac_enaddr[1] = 0xbd;
/*
* This no longer happens pre-scheduler so let's use the real
* random subsystem instead of random().
*/
macaddr_rnd = arc4random();
bcopy(&macaddr_rnd, &tp->arpcom.ac_enaddr[2], sizeof(u_int32_t));
tp->arpcom.ac_enaddr[5] = (u_char)unit + 1;
ifp = &tp->tun_if;
snprintf(ifp->if_xname, sizeof ifp->if_xname, "%s%d", ifc->ifc_name,
unit);
ifp->if_softc = tp;
ifp->if_ioctl = tun_ioctl;
ifp->if_output = tun_output;
ifp->if_start = tunstart;
IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
IFQ_SET_READY(&ifp->if_snd);
if ((flags & TUN_LAYER2) == 0) {
tp->tun_flags &= ~TUN_LAYER2;
ifp->if_mtu = ETHERMTU;
ifp->if_flags = IFF_POINTOPOINT;
ifp->if_type = IFT_TUNNEL;
ifp->if_hdrlen = sizeof(u_int32_t);
if_attach(ifp);
if_alloc_sadl(ifp);
#if NBPFILTER > 0
bpfattach(&ifp->if_bpf, ifp, DLT_LOOP, sizeof(u_int32_t));
#endif
} else {
tp->tun_flags |= TUN_LAYER2;
ifp->if_flags =
(IFF_BROADCAST|IFF_SIMPLEX|IFF_MULTICAST|IFF_LINK0);
if_attach(ifp);
ether_ifattach(ifp);
}
/* force output function to our function */
ifp->if_output = tun_output;
s = splnet();
LIST_INSERT_HEAD(&tun_softc_list, tp, tun_list);
splx(s);
return (0);
}
int
tun_clone_destroy(struct ifnet *ifp)
{
struct tun_softc *tp = ifp->if_softc;
int s;
tun_wakeup(tp);
s = splhigh();
klist_invalidate(&tp->tun_rsel.si_note);
klist_invalidate(&tp->tun_wsel.si_note);
splx(s);
s = splnet();
LIST_REMOVE(tp, tun_list);
splx(s);
if (tp->tun_flags & TUN_LAYER2)
ether_ifdetach(ifp);
if_detach(ifp);
free(tp, M_DEVBUF);
return (0);
}
struct tun_softc *
tun_lookup(int unit)
{
struct tun_softc *tp;
LIST_FOREACH(tp, &tun_softc_list, tun_list)
if (tp->tun_unit == unit)
return (tp);
return (NULL);
}
int
tun_switch(struct tun_softc *tp, int flags)
{
struct ifnet *ifp = &tp->tun_if;
int unit, open, r;
if ((tp->tun_flags & TUN_LAYER2) == (flags & TUN_LAYER2))
return (0);
/* tp will be removed so store unit number */
unit = tp->tun_unit;
open = tp->tun_flags & (TUN_OPEN|TUN_NBIO|TUN_ASYNC);
TUNDEBUG(("%s: switching to layer %d\n", ifp->if_xname,
flags & TUN_LAYER2 ? 2 : 3));
/* remove old device and ... */
tun_clone_destroy(ifp);
/* attach new interface */
r = tun_create(&tun_cloner, unit, flags);
if (open && r == 0) {
/* already opened before ifconfig tunX link0 */
if ((tp = tun_lookup(unit)) == NULL)
/* this should never fail */
return (ENXIO);
tp->tun_flags |= open;
TUNDEBUG(("%s: already open\n", tp->tun_if.if_xname));
}
return (r);
}
/*
* tunnel open - must be superuser & the device must be
* configured in
*/
int
tunopen(dev_t dev, int flag, int mode, struct proc *p)
{
struct tun_softc *tp;
struct ifnet *ifp;
int error, s;
if ((error = suser(p, 0)) != 0)
return (error);
if ((tp = tun_lookup(minor(dev))) == NULL) { /* create on demand */
char xname[IFNAMSIZ];
snprintf(xname, sizeof(xname), "%s%d", "tun", minor(dev));
if ((error = if_clone_create(xname)) != 0)
return (error);
if ((tp = tun_lookup(minor(dev))) == NULL)
return (ENXIO);
tp->tun_flags &= ~TUN_STAYUP;
}
if (tp->tun_flags & TUN_OPEN)
return (EBUSY);
ifp = &tp->tun_if;
tp->tun_flags |= TUN_OPEN;
/* automatically UP the interface on open */
s = splnet();
if_up(ifp);
ifp->if_flags |= IFF_RUNNING;
splx(s);
TUNDEBUG(("%s: open\n", ifp->if_xname));
return (0);
}
/*
* tunclose - close the device; if closing the real device, flush pending
* output and unless STAYUP bring down and destroy the interface.
*/
int
tunclose(dev_t dev, int flag, int mode, struct proc *p)
{
int s;
struct tun_softc *tp;
struct ifnet *ifp;
if ((tp = tun_lookup(minor(dev))) == NULL)
return (ENXIO);
ifp = &tp->tun_if;
tp->tun_flags &= ~(TUN_OPEN|TUN_NBIO|TUN_ASYNC);
ifp->if_flags &= ~IFF_RUNNING;
/*
* junk all pending output
*/
s = splnet();
IFQ_PURGE(&ifp->if_snd);
splx(s);
TUNDEBUG(("%s: closed\n", ifp->if_xname));
if (!(tp->tun_flags & TUN_STAYUP))
return (if_clone_destroy(ifp->if_xname));
else {
tp->tun_pgid = 0;
selwakeup(&tp->tun_rsel);
KNOTE(&tp->tun_rsel.si_note, 0);
}
return (0);
}
static int
tuninit(struct tun_softc *tp)
{
struct ifnet *ifp = &tp->tun_if;
struct ifaddr *ifa;
TUNDEBUG(("%s: tuninit\n", ifp->if_xname));
ifp->if_flags |= IFF_UP | IFF_RUNNING;
ifp->if_flags &= ~IFF_OACTIVE; /* we are never active */
tp->tun_flags &= ~(TUN_IASET|TUN_DSTADDR|TUN_BRDADDR);
TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
#ifdef INET
if (ifa->ifa_addr->sa_family == AF_INET) {
struct sockaddr_in *sin;
sin = satosin(ifa->ifa_addr);
if (sin && sin->sin_addr.s_addr)
tp->tun_flags |= TUN_IASET;
if (ifp->if_flags & IFF_POINTOPOINT) {
sin = satosin(ifa->ifa_dstaddr);
if (sin && sin->sin_addr.s_addr)
tp->tun_flags |= TUN_DSTADDR;
} else
tp->tun_flags &= ~TUN_DSTADDR;
if (ifp->if_flags & IFF_BROADCAST) {
sin = satosin(ifa->ifa_broadaddr);
if (sin && sin->sin_addr.s_addr)
tp->tun_flags |= TUN_BRDADDR;
} else
tp->tun_flags &= ~TUN_BRDADDR;
}
#endif
#ifdef INET6
if (ifa->ifa_addr->sa_family == AF_INET6) {
struct sockaddr_in6 *sin;
sin = (struct sockaddr_in6 *)ifa->ifa_addr;
if (!IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr))
tp->tun_flags |= TUN_IASET;
if (ifp->if_flags & IFF_POINTOPOINT) {
sin = (struct sockaddr_in6 *)ifa->ifa_dstaddr;
if (sin &&
!IN6_IS_ADDR_UNSPECIFIED(&sin->sin6_addr))
tp->tun_flags |= TUN_DSTADDR;
} else
tp->tun_flags &= ~TUN_DSTADDR;
}
#endif /* INET6 */
}
return (0);
}
/*
* Process an ioctl request.
*/
int
tun_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc);
struct ifreq *ifr = (struct ifreq *)data;
int error = 0, s;
s = splnet();
if (tp->tun_flags & TUN_LAYER2)
if ((error = ether_ioctl(ifp, &tp->arpcom, cmd, data)) > 0) {
splx(s);
return (error);
}
switch (cmd) {
case SIOCSIFADDR:
tuninit(tp);
TUNDEBUG(("%s: address set\n", ifp->if_xname));
if (tp->tun_flags & TUN_LAYER2)
switch (((struct ifaddr *)data)->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
arp_ifinit(&tp->arpcom, (struct ifaddr *)data);
break;
#endif
default:
break;
}
break;
case SIOCSIFDSTADDR:
tuninit(tp);
TUNDEBUG(("%s: destination address set\n", ifp->if_xname));
break;
case SIOCSIFBRDADDR:
tuninit(tp);
TUNDEBUG(("%s: broadcast address set\n", ifp->if_xname));
break;
case SIOCSIFMTU:
if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > TUNMRU)
error = EINVAL;
else
ifp->if_mtu = ifr->ifr_mtu;
break;
case SIOCADDMULTI:
case SIOCDELMULTI: {
if (ifr == 0) {
error = EAFNOSUPPORT; /* XXX */
break;
}
if (tp->tun_flags & TUN_LAYER2) {
error = (cmd == SIOCADDMULTI) ?
ether_addmulti(ifr, &tp->arpcom) :
ether_delmulti(ifr, &tp->arpcom);
if (error == ENETRESET) {
/*
* Multicast list has changed; set the hardware
* filter accordingly. The good thing is we do
* not have a hardware filter (:
*/
error = 0;
}
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 SIOCSIFFLAGS:
error = tun_switch(tp,
ifp->if_flags & IFF_LINK0 ? TUN_LAYER2 : 0);
break;
default:
error = EINVAL;
}
splx(s);
return (error);
}
/*
* tun_output - queue packets from higher level ready to put out.
*/
int
tun_output(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
struct rtentry *rt)
{
struct tun_softc *tp = ifp->if_softc;
int s, len, error;
u_int32_t *af;
if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
m_freem(m0);
return (EHOSTDOWN);
}
TUNDEBUG(("%s: tun_output\n", ifp->if_xname));
if ((tp->tun_flags & TUN_READY) != TUN_READY) {
TUNDEBUG(("%s: not ready %#x\n", ifp->if_xname,
tp->tun_flags));
m_freem(m0);
return (EHOSTDOWN);
}
if (tp->tun_flags & TUN_LAYER2)
/* call ether_output and that will call tunstart at the end */
return (ether_output(ifp, m0, dst, rt));
M_PREPEND(m0, sizeof(*af), M_DONTWAIT);
af = mtod(m0, u_int32_t *);
*af = htonl(dst->sa_family);
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, m0, BPF_DIRECTION_OUT);
#endif
len = m0->m_pkthdr.len + sizeof(*af);
s = splnet();
IFQ_ENQUEUE(&ifp->if_snd, m0, NULL, error);
if (error) {
splx(s);
ifp->if_collisions++;
return (error);
}
splx(s);
ifp->if_opackets++;
ifp->if_obytes += len;
tun_wakeup(tp);
return (0);
}
void
tun_wakeup(struct tun_softc *tp)
{
if (tp->tun_flags & TUN_RWAIT) {
tp->tun_flags &= ~TUN_RWAIT;
wakeup((caddr_t)tp);
}
if (tp->tun_flags & TUN_ASYNC && tp->tun_pgid)
csignal(tp->tun_pgid, SIGIO,
tp->tun_siguid, tp->tun_sigeuid);
selwakeup(&tp->tun_rsel);
KNOTE(&tp->tun_rsel.si_note, 0);
}
/*
* the cdevsw interface is now pretty minimal.
*/
int
tunioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
int s;
struct tun_softc *tp;
struct tuninfo *tunp;
struct mbuf *m;
if ((tp = tun_lookup(minor(dev))) == NULL)
return (ENXIO);
s = splnet();
switch (cmd) {
case TUNSIFINFO:
tunp = (struct tuninfo *)data;
if (tunp->mtu < ETHERMIN || tunp->mtu > TUNMRU) {
splx(s);
return (EINVAL);
}
tp->tun_if.if_mtu = tunp->mtu;
tp->tun_if.if_type = tunp->type;
tp->tun_if.if_flags =
(tunp->flags & TUN_IFF_FLAGS) |
(tp->tun_if.if_flags & ~TUN_IFF_FLAGS);
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->flags = tp->tun_if.if_flags;
tunp->baudrate = tp->tun_if.if_baudrate;
break;
#ifdef TUN_DEBUG
case TUNSDEBUG:
tundebug = *(int *)data;
break;
case TUNGDEBUG:
*(int *)data = tundebug;
break;
#endif
case TUNSIFMODE:
switch (*(int *)data & (IFF_POINTOPOINT|IFF_BROADCAST)) {
case IFF_POINTOPOINT:
case IFF_BROADCAST:
tp->tun_if.if_flags &= ~TUN_IFF_FLAGS;
tp->tun_if.if_flags |= *(int *)data & TUN_IFF_FLAGS;
break;
default:
splx(s);
return (EINVAL);
}
break;
case FIONBIO:
if (*(int *)data)
tp->tun_flags |= TUN_NBIO;
else
tp->tun_flags &= ~TUN_NBIO;
break;
case FIOASYNC:
if (*(int *)data)
tp->tun_flags |= TUN_ASYNC;
else
tp->tun_flags &= ~TUN_ASYNC;
break;
case FIONREAD:
IFQ_POLL(&tp->tun_if.if_snd, m);
if (m != NULL)
*(int *)data = m->m_pkthdr.len;
else
*(int *)data = 0;
break;
case TIOCSPGRP:
tp->tun_pgid = *(int *)data;
tp->tun_siguid = p->p_cred->p_ruid;
tp->tun_sigeuid = p->p_ucred->cr_uid;
break;
case TIOCGPGRP:
*(int *)data = tp->tun_pgid;
break;
case OSIOCGIFADDR:
case SIOCGIFADDR:
if (!(tp->tun_flags & TUN_LAYER2)) {
splx(s);
return (EINVAL);
}
bcopy(tp->arpcom.ac_enaddr, data,
sizeof(tp->arpcom.ac_enaddr));
break;
case SIOCSIFADDR:
if (!(tp->tun_flags & TUN_LAYER2)) {
splx(s);
return (EINVAL);
}
bcopy(data, tp->arpcom.ac_enaddr,
sizeof(tp->arpcom.ac_enaddr));
break;
default:
splx(s);
return (ENOTTY);
}
splx(s);
return (0);
}
/*
* The cdevsw read interface - reads a packet at a time, or at
* least as much of a packet as can be read.
*/
int
tunread(dev_t dev, struct uio *uio, int ioflag)
{
struct tun_softc *tp;
struct ifnet *ifp;
struct mbuf *m, *m0;
int error = 0, len, s;
if ((tp = tun_lookup(minor(dev))) == NULL)
return (ENXIO);
ifp = &tp->tun_if;
TUNDEBUG(("%s: read\n", ifp->if_xname));
if ((tp->tun_flags & TUN_READY) != TUN_READY) {
TUNDEBUG(("%s: not ready %#x\n", ifp->if_xname, tp->tun_flags));
return (EHOSTDOWN);
}
tp->tun_flags &= ~TUN_RWAIT;
s = splnet();
do {
while ((tp->tun_flags & TUN_READY) != TUN_READY)
if ((error = tsleep((caddr_t)tp,
(PZERO + 1)|PCATCH, "tunread", 0)) != 0) {
splx(s);
return (error);
}
IFQ_DEQUEUE(&ifp->if_snd, m0);
if (m0 == NULL) {
if (tp->tun_flags & TUN_NBIO && ioflag & IO_NDELAY) {
splx(s);
return (EWOULDBLOCK);
}
tp->tun_flags |= TUN_RWAIT;
if ((error = tsleep((caddr_t)tp,
(PZERO + 1)|PCATCH, "tunread", 0)) != 0) {
splx(s);
return (error);
}
}
} while (m0 == NULL);
splx(s);
while (m0 != NULL && uio->uio_resid > 0 && error == 0) {
len = min(uio->uio_resid, m0->m_len);
if (len != 0)
error = uiomove(mtod(m0, caddr_t), len, uio);
MFREE(m0, m);
m0 = m;
}
if (m0 != NULL) {
TUNDEBUG(("Dropping mbuf\n"));
m_freem(m0);
}
if (error)
ifp->if_ierrors++;
return (error);
}
/*
* the cdevsw write interface - an atomic write is a packet - or else!
*/
int
tunwrite(dev_t dev, struct uio *uio, int ioflag)
{
struct tun_softc *tp;
struct ifnet *ifp;
struct ifqueue *ifq;
u_int32_t *th;
struct mbuf *top, **mp, *m;
int isr;
int error=0, s, tlen, mlen;
if ((tp = tun_lookup(minor(dev))) == NULL)
return (ENXIO);
ifp = &tp->tun_if;
TUNDEBUG(("%s: tunwrite\n", ifp->if_xname));
if (uio->uio_resid == 0 || uio->uio_resid > ifp->if_mtu +
(tp->tun_flags & TUN_LAYER2 ? ETHER_HDR_LEN : sizeof(*th))) {
TUNDEBUG(("%s: len=%d!\n", ifp->if_xname, uio->uio_resid));
return (EMSGSIZE);
}
tlen = uio->uio_resid;
/* get a header mbuf */
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL)
return (ENOBUFS);
mlen = MHLEN;
if (uio->uio_resid >= MINCLSIZE) {
MCLGET(m, M_DONTWAIT);
if (!(m->m_flags & M_EXT)) {
m_free(m);
return (ENOBUFS);
}
mlen = MCLBYTES;
}
top = NULL;
mp = ⊤
if (tp->tun_flags & TUN_LAYER2) {
/*
* Pad so that IP header is correctly aligned
* this is necessary for all strict aligned architectures.
*/
mlen -= ETHER_ALIGN;
m->m_data += ETHER_ALIGN;
}
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 (error == 0 && uio->uio_resid > 0) {
MGET(m, M_DONTWAIT, MT_DATA);
if (m == NULL) {
error = ENOBUFS;
break;
}
mlen = MLEN;
if (uio->uio_resid >= MINCLSIZE) {
MCLGET(m, M_DONTWAIT);
if (!(m->m_flags & M_EXT)) {
error = ENOBUFS;
m_free(m);
break;
}
mlen = MCLBYTES;
}
}
}
if (error) {
if (top != NULL)
m_freem(top);
ifp->if_ierrors++;
return (error);
}
top->m_pkthdr.len = tlen;
top->m_pkthdr.rcvif = ifp;
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, top, BPF_DIRECTION_IN);
#endif
if (tp->tun_flags & TUN_LAYER2) {
ether_input_mbuf(ifp, top);
ifp->if_ipackets++; /* ibytes are counted in ether_input */
return (0);
}
th = mtod(top, u_int32_t *);
/* strip the tunnel header */
top->m_data += sizeof(*th);
top->m_len -= sizeof(*th);
top->m_pkthdr.len -= sizeof(*th);
switch (ntohl(*th)) {
#ifdef INET
case AF_INET:
ifq = &ipintrq;
isr = NETISR_IP;
break;
#endif
#ifdef INET6
case AF_INET6:
ifq = &ip6intrq;
isr = NETISR_IPV6;
break;
#endif
#ifdef NETATALK
case AF_APPLETALK:
ifq = &atintrq2;
isr = NETISR_ATALK;
break;
#endif
default:
m_freem(top);
return (EAFNOSUPPORT);
}
s = splnet();
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
splx(s);
ifp->if_collisions++;
m_freem(top);
if (!ifq->ifq_congestion)
if_congestion(ifq);
return (ENOBUFS);
}
IF_ENQUEUE(ifq, top);
schednetisr(isr);
ifp->if_ipackets++;
ifp->if_ibytes += top->m_pkthdr.len;
splx(s);
return (error);
}
/*
* 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.
*/
int
tunpoll(dev_t dev, int events, struct proc *p)
{
int revents, s;
struct tun_softc *tp;
struct ifnet *ifp;
struct mbuf *m;
if ((tp = tun_lookup(minor(dev))) == NULL)
return (POLLERR);
ifp = &tp->tun_if;
revents = 0;
s = splnet();
TUNDEBUG(("%s: tunpoll\n", ifp->if_xname));
if (events & (POLLIN | POLLRDNORM)) {
IFQ_POLL(&ifp->if_snd, m);
if (m != NULL) {
TUNDEBUG(("%s: tunselect q=%d\n", ifp->if_xname,
ifp->if_snd.ifq_len));
revents |= events & (POLLIN | POLLRDNORM);
} else {
TUNDEBUG(("%s: tunpoll waiting\n", ifp->if_xname));
selrecord(p, &tp->tun_rsel);
}
}
if (events & (POLLOUT | POLLWRNORM))
revents |= events & (POLLOUT | POLLWRNORM);
splx(s);
return (revents);
}
/*
* kqueue(2) support.
*
* The tun driver uses an array of tun_softc's based on the minor number
* of the device. kn->kn_hook gets set to the specific tun_softc.
*
* filt_tunread() sets kn->kn_data to the iface qsize
* filt_tunwrite() sets kn->kn_data to the MTU size
*/
int
tunkqfilter(dev_t dev, struct knote *kn)
{
int s;
struct klist *klist;
struct tun_softc *tp;
struct ifnet *ifp;
if ((tp = tun_lookup(minor(dev))) == NULL)
return (ENXIO);
ifp = &tp->tun_if;
s = splnet();
TUNDEBUG(("%s: tunkqfilter\n", ifp->if_xname));
splx(s);
switch (kn->kn_filter) {
case EVFILT_READ:
klist = &tp->tun_rsel.si_note;
kn->kn_fop = &tunread_filtops;
break;
case EVFILT_WRITE:
klist = &tp->tun_wsel.si_note;
kn->kn_fop = &tunwrite_filtops;
break;
default:
return (EPERM); /* 1 */
}
kn->kn_hook = (caddr_t)tp;
s = splhigh();
SLIST_INSERT_HEAD(klist, kn, kn_selnext);
splx(s);
return (0);
}
void
filt_tunrdetach(struct knote *kn)
{
int s;
struct tun_softc *tp;
tp = (struct tun_softc *)kn->kn_hook;
s = splhigh();
if (!(kn->kn_status & KN_DETACHED))
SLIST_REMOVE(&tp->tun_rsel.si_note, kn, knote, kn_selnext);
splx(s);
}
int
filt_tunread(struct knote *kn, long hint)
{
int s;
struct tun_softc *tp;
struct ifnet *ifp;
struct mbuf *m;
if (kn->kn_status & KN_DETACHED) {
kn->kn_data = 0;
return (1);
}
tp = (struct tun_softc *)kn->kn_hook;
ifp = &tp->tun_if;
s = splnet();
IFQ_POLL(&ifp->if_snd, m);
if (m != NULL) {
splx(s);
kn->kn_data = ifp->if_snd.ifq_len;
TUNDEBUG(("%s: tunkqread q=%d\n", ifp->if_xname,
ifp->if_snd.ifq_len));
return (1);
}
splx(s);
TUNDEBUG(("%s: tunkqread waiting\n", ifp->if_xname));
return (0);
}
void
filt_tunwdetach(struct knote *kn)
{
int s;
struct tun_softc *tp;
tp = (struct tun_softc *)kn->kn_hook;
s = splhigh();
if (!(kn->kn_status & KN_DETACHED))
SLIST_REMOVE(&tp->tun_wsel.si_note, kn, knote, kn_selnext);
splx(s);
}
int
filt_tunwrite(struct knote *kn, long hint)
{
struct tun_softc *tp;
struct ifnet *ifp;
if (kn->kn_status & KN_DETACHED) {
kn->kn_data = 0;
return (1);
}
tp = (struct tun_softc *)kn->kn_hook;
ifp = &tp->tun_if;
kn->kn_data = ifp->if_mtu;
return (1);
}
/*
* Start packet transmission on the interface.
* when the interface queue is rate-limited by ALTQ or TBR,
* if_start is needed to drain packets from the queue in order
* to notify readers when outgoing packets become ready.
* In layer 2 mode this function is called from ether_output.
*/
static void
tunstart(struct ifnet *ifp)
{
struct tun_softc *tp = ifp->if_softc;
struct mbuf *m;
if (!(tp->tun_flags & TUN_LAYER2) &&
!ALTQ_IS_ENABLED(&ifp->if_snd) &&
!TBR_IS_ENABLED(&ifp->if_snd))
return;
IFQ_POLL(&ifp->if_snd, m);
if (m != NULL) {
if (tp->tun_flags & TUN_LAYER2) {
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_OUT);
#endif
ifp->if_opackets++;
}
tun_wakeup(tp);
}
}