Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Turn the tun device/network interface into a cloning device.

Browse Source
This commit is contained in:
atatat 2001-10-31 20:08:17 +00:00
parent dadd6e7370
commit 6e885d365a
3 changed files with 258 additions and 57 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
share/man/man4/tun.4
View File

@ -1,4 +1,4 @@
.\" $NetBSD: tun.4,v 1.10 2001/09/22 16:36:24 wiz Exp $
.\" $NetBSD: tun.4,v 1.11 2001/10/31 20:08:18 atatat Exp $
.\" Based on PR#2411
.\"
.Dd March 10, 1996
@ -37,6 +37,21 @@ and a character-special device
.Dq control
interface.
.Pp
To use a
.Nm tun
device, the administrator must first create the interface. This can
be done by using the
.Xr ifconfig 8
`create' command, or via the
.Dv SIOCIFCREATE
ioctl. Note that an
.Fn open
call on
.Pa /dev/tun Ns Sy N ,
will indicate that the device is not configured
.Pq Er ENXIO
unless the corresponding network interface has been created.
.Pp
The network interfaces are named
.Sy tun Ns Ar 0 ,
.Sy tun Ns Ar 1 ,
@ -58,9 +73,8 @@ interfaces, but this can be changed; see the description of the control
device, below. When the system chooses to transmit a packet on the
network interface, the packet can be read from the control device
.Po
it appears as
.Dq input
there
it appears there as
.Dq output
.Pc ;
writing a packet to the control device generates an input
packet on the network interface, as if the
@ -73,14 +87,17 @@ is exclusive-open
.Po
it cannot be opened if it is already open
.Pc
and is restricted to the super-user. A
and is restricted to the super-user
.Po
regardless of file system permissions
.Pc . A
.Fn read
call will return an error
.Pq Er EHOSTDOWN
if the interface is not
.Dq ready
(which means that the control device is open and the interface
address has been set).
(which means that the interface
address has not been set).
Once the interface is ready,
.Fn read
will return a packet if one is available; if not, it will either block

276
sys/net/if_tun.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: if_tun.c,v 1.45 2001/08/03 21:11:57 itojun Exp $ */
/* $NetBSD: if_tun.c,v 1.46 2001/10/31 20:08:17 atatat Exp $ */
/*
* Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk>
@ -68,46 +68,135 @@
#define TUNDEBUG if (tundebug) printf
int tundebug = 0;
struct tun_softc tunctl[NTUN];
extern int ifqmaxlen;
void tunattach __P((int));
LIST_HEAD(, tun_softc) tun_softc_list;
static struct simplelock tun_softc_lock;
int tun_ioctl __P((struct ifnet *, u_long, caddr_t));
int tun_output __P((struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *rt));
int tun_clone_create __P((struct if_clone *, int));
void tun_clone_destroy __P((struct ifnet *));
struct if_clone tun_cloner =
IF_CLONE_INITIALIZER("tun", tun_clone_create, tun_clone_destroy);
static void tunattach0 __P((struct tun_softc *));
static void tuninit __P((struct tun_softc *));
static struct tun_softc *tun_find_unit __P((dev_t));
void
tunattach(unused)
int unused;
{
int i;
struct ifnet *ifp;
for (i = 0; i < NTUN; i++) {
tunctl[i].tun_flags = TUN_INITED;
simple_lock_init(&tun_softc_lock);
LIST_INIT(&tun_softc_list);
if_clone_attach(&tun_cloner);
}
ifp = &tunctl[i].tun_if;
sprintf(ifp->if_xname, "tun%d", i);
ifp->if_softc = &tunctl[i];
ifp->if_mtu = TUNMTU;
ifp->if_ioctl = tun_ioctl;
ifp->if_output = tun_output;
ifp->if_flags = IFF_POINTOPOINT;
ifp->if_snd.ifq_maxlen = ifqmaxlen;
ifp->if_collisions = 0;
ifp->if_ierrors = 0;
ifp->if_oerrors = 0;
ifp->if_ipackets = 0;
ifp->if_opackets = 0;
ifp->if_dlt = DLT_NULL;
if_attach(ifp);
if_alloc_sadl(ifp);
int
tun_clone_create(ifc, unit)
struct if_clone *ifc;
int unit;
{
struct tun_softc *sc;
sc = malloc(sizeof(struct tun_softc), M_DEVBUF, M_WAITOK);
(void)memset(sc, 0, sizeof(struct tun_softc));
(void)snprintf(sc->tun_if.if_xname, sizeof(sc->tun_if.if_xname),
"%s%d", ifc->ifc_name, unit);
sc->tun_unit = unit;
simple_lock_init(&sc->tun_lock);
tunattach0(sc);
simple_lock(&tun_softc_lock);
LIST_INSERT_HEAD(&tun_softc_list, sc, tun_list);
simple_unlock(&tun_softc_lock);
return (0);
}
void
tunattach0(sc)
struct tun_softc *sc;
{
struct ifnet *ifp = (void *)sc;
sc->tun_flags = TUN_INITED;
ifp = &sc->tun_if;
ifp->if_softc = sc;
ifp->if_mtu = TUNMTU;
ifp->if_ioctl = tun_ioctl;
ifp->if_output = tun_output;
ifp->if_flags = IFF_POINTOPOINT;
ifp->if_snd.ifq_maxlen = ifqmaxlen;
ifp->if_collisions = 0;
ifp->if_ierrors = 0;
ifp->if_oerrors = 0;
ifp->if_ipackets = 0;
ifp->if_opackets = 0;
ifp->if_dlt = DLT_NULL;
if_attach(ifp);
if_alloc_sadl(ifp);
#if NBPFILTER > 0
bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
#endif
}
void
tun_clone_destroy(ifp)
struct ifnet *ifp;
{
struct tun_softc *tp = (void *)ifp;
struct proc *p;
simple_lock(&tun_softc_lock);
simple_lock(&tp->tun_lock);
LIST_REMOVE(tp, tun_list);
simple_unlock(&tp->tun_lock);
simple_unlock(&tun_softc_lock);
if (tp->tun_flags & TUN_RWAIT) {
tp->tun_flags &= ~TUN_RWAIT;
wakeup((caddr_t)tp);
}
if (tp->tun_flags & TUN_ASYNC && tp->tun_pgrp) {
if (tp->tun_pgrp > 0)
gsignal(tp->tun_pgrp, SIGIO);
else if ((p = pfind(-tp->tun_pgrp)) != NULL)
psignal(p, SIGIO);
}
selwakeup(&tp->tun_rsel);
#if NBPFILTER > 0
bpfdetach(ifp);
#endif
if_detach(ifp);
free(tp, M_DEVBUF);
}
static struct tun_softc *
tun_find_unit(dev)
dev_t dev;
{
struct tun_softc *tp;
int unit = minor(dev);
simple_lock(&tun_softc_lock);
LIST_FOREACH(tp, &tun_softc_list, tun_list)
if (unit == tp->tun_unit)
break;
if (tp)
simple_lock(&tp->tun_lock);
simple_unlock(&tun_softc_lock);
return (tp);
}
/*
@ -122,19 +211,28 @@ tunopen(dev, flag, mode, p)
{
struct ifnet *ifp;
struct tun_softc *tp;
int unit, error;
int error;
if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
return (error);
if ((unit = minor(dev)) >= NTUN)
if (NTUN < 1)
return (ENXIO);
tp = &tunctl[unit];
if (tp->tun_flags & TUN_OPEN)
return ENXIO;
tp = tun_find_unit(dev);
if (!tp)
return (ENXIO);
if (tp->tun_flags & TUN_OPEN) {
simple_unlock(&tp->tun_lock);
return (EBUSY);
}
ifp = &tp->tun_if;
tp->tun_flags |= TUN_OPEN;
TUNDEBUG("%s: open\n", ifp->if_xname);
simple_unlock(&tp->tun_lock);
return (0);
}
@ -149,11 +247,19 @@ tunclose(dev, flag, mode, p)
int mode;
struct proc *p;
{
int unit = minor(dev), s;
struct tun_softc *tp = &tunctl[unit];
struct ifnet *ifp = &tp->tun_if;
int s;
struct tun_softc *tp;
struct ifnet *ifp;
struct mbuf *m;
tp = tun_find_unit(dev);
/* interface was "destroyed" before the close */
if (tp == NULL)
return (0);
ifp = &tp->tun_if;
tp->tun_flags &= ~TUN_OPEN;
/*
@ -191,6 +297,7 @@ tunclose(dev, flag, mode, p)
selwakeup(&tp->tun_rsel);
TUNDEBUG ("%s: closed\n", ifp->if_xname);
simple_unlock(&tp->tun_lock);
return (0);
}
@ -199,7 +306,7 @@ tuninit(tp)
struct tun_softc *tp;
{
struct ifnet *ifp = &tp->tun_if;
struct ifaddr *ifa;
struct ifaddr *ifa;
TUNDEBUG("%s: tuninit\n", ifp->if_xname);
@ -238,6 +345,9 @@ tun_ioctl(ifp, cmd, data)
caddr_t data;
{
int error = 0, s;
struct tun_softc *tp = (struct tun_softc *)(ifp->if_softc);
simple_lock(&tp->tun_lock);
s = splnet();
switch(cmd) {
@ -288,6 +398,7 @@ tun_ioctl(ifp, cmd, data)
error = EINVAL;
}
splx(s);
simple_unlock(&tp->tun_lock);
return (error);
}
@ -307,12 +418,14 @@ tun_output(ifp, m0, dst, rt)
int s;
#endif
simple_lock(&tp->tun_lock);
TUNDEBUG ("%s: tun_output\n", ifp->if_xname);
if ((tp->tun_flags & TUN_READY) != TUN_READY) {
TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname,
tp->tun_flags);
m_freem (m0);
simple_unlock(&tp->tun_lock);
return (EHOSTDOWN);
}
@ -344,6 +457,7 @@ tun_output(ifp, m0, dst, rt)
M_PREPEND(m0, dst->sa_len, M_DONTWAIT);
if (m0 == NULL) {
IF_DROP(&ifp->if_snd);
simple_unlock(&tp->tun_lock);
return (ENOBUFS);
}
bcopy(dst, mtod(m0, char *), dst->sa_len);
@ -356,6 +470,7 @@ tun_output(ifp, m0, dst, rt)
m_freem(m0);
splx(s);
ifp->if_collisions++;
simple_unlock(&tp->tun_lock);
return (ENOBUFS);
}
IF_ENQUEUE(&ifp->if_snd, m0);
@ -365,6 +480,7 @@ tun_output(ifp, m0, dst, rt)
#endif
default:
m_freem(m0);
simple_unlock(&tp->tun_lock);
return (EAFNOSUPPORT);
}
@ -379,6 +495,7 @@ tun_output(ifp, m0, dst, rt)
psignal(p, SIGIO);
}
selwakeup(&tp->tun_rsel);
simple_unlock(&tp->tun_lock);
return (0);
}
@ -393,8 +510,14 @@ tunioctl(dev, cmd, data, flag, p)
int flag;
struct proc *p;
{
int unit = minor(dev), s;
struct tun_softc *tp = &tunctl[unit];
int s;
struct tun_softc *tp;
tp = tun_find_unit(dev);
/* interface was "destroyed" already */
if (tp == NULL)
return (ENXIO);
switch (cmd) {
case TUNSDEBUG:
@ -412,6 +535,7 @@ tunioctl(dev, cmd, data, flag, p)
s = splnet();
if (tp->tun_if.if_flags & IFF_UP) {
splx(s);
simple_unlock(&tp->tun_lock);
return (EBUSY);
}
tp->tun_if.if_flags &=
@ -420,6 +544,7 @@ tunioctl(dev, cmd, data, flag, p)
splx(s);
break;
default:
simple_unlock(&tp->tun_lock);
return (EINVAL);
break;
}
@ -464,8 +589,10 @@ tunioctl(dev, cmd, data, flag, p)
break;
default:
simple_unlock(&tp->tun_lock);
return (ENOTTY);
}
simple_unlock(&tp->tun_lock);
return (0);
}
@ -479,15 +606,24 @@ tunread(dev, uio, ioflag)
struct uio *uio;
int ioflag;
{
int unit = minor(dev);
struct tun_softc *tp = &tunctl[unit];
struct ifnet *ifp = &tp->tun_if;
struct tun_softc *tp;
struct ifnet *ifp;
struct mbuf *m, *m0;
int error=0, len, s;
int error=0, len, s, index;
tp = tun_find_unit(dev);
/* interface was "destroyed" already */
if (tp == NULL)
return (ENXIO);
index = tp->tun_if.if_index;
ifp = &tp->tun_if;
TUNDEBUG ("%s: read\n", ifp->if_xname);
if ((tp->tun_flags & TUN_READY) != TUN_READY) {
TUNDEBUG ("%s: not ready 0%o\n", ifp->if_xname, tp->tun_flags);
simple_unlock(&tp->tun_lock);
return EHOSTDOWN;
}
@ -499,12 +635,29 @@ tunread(dev, uio, ioflag)
if (m0 == 0) {
if (tp->tun_flags & TUN_NBIO) {
splx(s);
simple_unlock(&tp->tun_lock);
return (EWOULDBLOCK);
}
tp->tun_flags |= TUN_RWAIT;
simple_unlock(&tp->tun_lock);
if (tsleep((caddr_t)tp, PZERO|PCATCH, "tunread", 0)) {
splx(s);
return (EINTR);
} else {
/*
* Maybe the interface was destroyed while
* we were sleeping, so let's ensure that
* we're looking at the same (valid) tun
* interface before looping.
*/
tp = tun_find_unit(dev);
if (tp == NULL ||
tp->tun_if.if_index != index) {
splx(s);
if (tp)
simple_unlock(&tp->tun_lock);
return (ENXIO);
}
}
}
} while (m0 == 0);
@ -524,6 +677,7 @@ tunread(dev, uio, ioflag)
}
if (error)
ifp->if_ierrors++;
simple_unlock(&tp->tun_lock);
return (error);
}
@ -536,27 +690,38 @@ tunwrite(dev, uio, ioflag)
struct uio *uio;
int ioflag;
{
int unit = minor (dev);
struct tun_softc *tp = &tunctl[unit];
struct ifnet *ifp = &tp->tun_if;
struct tun_softc *tp;
struct ifnet *ifp;
struct mbuf *top, **mp, *m;
struct ifqueue *ifq;
struct sockaddr dst;
int isr, error=0, s, tlen, mlen;
tp = tun_find_unit(dev);
/* interface was "destroyed" already */
if (tp == NULL)
return (ENXIO);
ifp = &tp->tun_if;
TUNDEBUG("%s: tunwrite\n", ifp->if_xname);
if (tp->tun_flags & TUN_PREPADDR) {
if (uio->uio_resid < sizeof(dst))
if (uio->uio_resid < sizeof(dst)) {
simple_unlock(&tp->tun_lock);
return (EIO);
}
error = uiomove((caddr_t)&dst, sizeof(dst), uio);
if (dst.sa_len > sizeof(dst)) {
/* Duh.. */
char discard;
int n = dst.sa_len - sizeof(dst);
while (n--)
if ((error = uiomove(&discard, 1, uio)) != 0)
if ((error = uiomove(&discard, 1, uio)) != 0) {
simple_unlock(&tp->tun_lock);
return (error);
}
}
} else {
#ifdef INET
@ -567,6 +732,7 @@ tunwrite(dev, uio, ioflag)
if (uio->uio_resid < 0 || uio->uio_resid > TUNMTU) {
TUNDEBUG("%s: len=%lu!\n", ifp->if_xname,
(unsigned long)uio->uio_resid);
simple_unlock(&tp->tun_lock);
return (EIO);
}
@ -578,6 +744,7 @@ tunwrite(dev, uio, ioflag)
break;
#endif
default:
simple_unlock(&tp->tun_lock);
return (EAFNOSUPPORT);
}
@ -585,8 +752,10 @@ tunwrite(dev, uio, ioflag)
/* get a header mbuf */
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL)
if (m == NULL) {
simple_unlock(&tp->tun_lock);
return (ENOBUFS);
}
mlen = MHLEN;
top = 0;
@ -609,6 +778,7 @@ tunwrite(dev, uio, ioflag)
if (top)
m_freem (top);
ifp->if_ierrors++;
simple_unlock(&tp->tun_lock);
return (error);
}
@ -641,12 +811,14 @@ tunwrite(dev, uio, ioflag)
splx(s);
ifp->if_collisions++;
m_freem(top);
simple_unlock(&tp->tun_lock);
return (ENOBUFS);
}
IF_ENQUEUE(ifq, top);
splx(s);
ifp->if_ipackets++;
schednetisr(isr);
simple_unlock(&tp->tun_lock);
return (error);
}
@ -661,10 +833,17 @@ tunpoll(dev, events, p)
int events;
struct proc *p;
{
int unit = minor(dev), s;
struct tun_softc *tp = &tunctl[unit];
struct ifnet *ifp = &tp->tun_if;
int revents = 0;
struct tun_softc *tp;
struct ifnet *ifp;
int s, revents = 0;
tp = tun_find_unit(dev);
/* interface was "destroyed" already */
if (tp == NULL)
return (0);
ifp = &tp->tun_if;
s = splnet();
TUNDEBUG("%s: tunpoll\n", ifp->if_xname);
@ -684,6 +863,7 @@ tunpoll(dev, events, p)
revents |= events & (POLLOUT | POLLWRNORM);
splx(s);
simple_unlock(&tp->tun_lock);
return (revents);
}

8
sys/net/if_tun.h
View File

@ -1,4 +1,4 @@
/* $NetBSD: if_tun.h,v 1.9 2000/12/12 18:00:31 thorpej Exp $ */
/* $NetBSD: if_tun.h,v 1.10 2001/10/31 20:08:17 atatat Exp $ */
/*
* Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk>
@ -21,6 +21,8 @@
#ifdef _KERNEL
struct tun_softc {
struct ifnet tun_if; /* the interface */
u_short tun_flags; /* misc flags */
#define TUN_OPEN 0x0001
#define TUN_INITED 0x0002
@ -34,10 +36,12 @@ struct tun_softc {
#define TUN_READY (TUN_OPEN | TUN_INITED | TUN_IASET)
struct ifnet tun_if; /* the interface */
int tun_pgrp; /* the process group - if any */
struct selinfo tun_rsel; /* read select */
struct selinfo tun_wsel; /* write select (not used) */
int tun_unit; /* the tunnel unit number */
struct simplelock tun_lock; /* lock for this tunnel */
LIST_ENTRY(tun_softc) tun_list; /* list of all tuns */
};
#endif /* _KERNEL */