478 lines
9.3 KiB
C
478 lines
9.3 KiB
C
/*
|
|
* Copyright (c) 1988, Julian Onions.
|
|
*
|
|
* This source may be freely distributed, however I would be interested
|
|
* in any changes that are made.
|
|
*
|
|
* if_tun.c - tunnel interface module & driver
|
|
*
|
|
* $Id: if_tun.c,v 1.7 1993/11/14 20:33:26 deraadt Exp $
|
|
*/
|
|
|
|
#include "tun.h"
|
|
#if NTUN > 0
|
|
|
|
/*
|
|
* Tunnel driver.
|
|
*
|
|
* This driver takes packets off the IP i/f and hands them up to a
|
|
* user process to have it's 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/select mode of
|
|
* operation though.
|
|
*
|
|
* Julian Onions <jpo@cs.nott.ac.uk>
|
|
* Nottingham University 1987.
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/buf.h>
|
|
#include <sys/protosw.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/errno.h>
|
|
#include <sys/syslog.h>
|
|
#include <sys/select.h>
|
|
|
|
#include <net/if.h>
|
|
#include <net/if_tun.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 NS
|
|
#include <netns/ns.h>
|
|
#include <netns/ns_if.h>
|
|
#endif
|
|
|
|
#define TUNDEBUG if (tundebug) printf
|
|
int tundebug = 0;
|
|
|
|
struct tun_softc tunctl[NTUN];
|
|
extern int ifqmaxlen;
|
|
|
|
int tunoutput __P((dev_t, int, int, struct proc *));
|
|
int tunclose __P((dev_t, int));
|
|
int tunoutput __P((struct ifnet *, struct mbuf *, struct sockaddr *));
|
|
int tunread __P((dev_t, struct uio *));
|
|
int tunwrite __P((dev_t, struct uio *));
|
|
int tuncioctl __P((dev_t, int, caddr_t, data);
|
|
int tunioctl __P((struct ifnet *, int, caddr_t, int));
|
|
int tunselect __P((dev_t, int);
|
|
|
|
static int tunattach __P((int));
|
|
static int tuninit __P((int));
|
|
|
|
/*
|
|
* tunnel open - must be superuser & the device must be
|
|
* configured in
|
|
*/
|
|
int
|
|
tunopen(dev, flag, mode, p)
|
|
dev_t dev;
|
|
int flag, mode;
|
|
struct proc *p;
|
|
{
|
|
struct ifnet *ifp;
|
|
struct tunctl *tp;
|
|
register int unit, error;
|
|
|
|
if (error = suser(p->p_ucred, &p->p_acflag))
|
|
return (error);
|
|
|
|
if ((unit = minor(dev)) >= NTUN)
|
|
return (ENXIO);
|
|
tp = &tunctl[unit];
|
|
if (tp->tun_flags & TUN_OPEN)
|
|
return ENXIO;
|
|
if ((tp->tun_flags & TUN_INITED) == 0) {
|
|
tp->tun_flags = TUN_INITED;
|
|
tunattach(unit);
|
|
}
|
|
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
|
|
*/
|
|
int
|
|
tunclose(dev, flag)
|
|
dev_t dev;
|
|
int flag;
|
|
{
|
|
struct tunctl *tp = &tunctl[unit];
|
|
struct ifnet *ifp = &tp->tun_if;
|
|
struct mbuf *m;
|
|
register int unit = minor(dev), s;
|
|
|
|
tp->tun_flags &= TUN_INITED;
|
|
|
|
/*
|
|
* junk all pending output
|
|
*/
|
|
do {
|
|
s = splimp();
|
|
IF_DEQUEUE(&ifp->if_snd, m);
|
|
splx(s);
|
|
if (m)
|
|
m_freem(m);
|
|
} while (m);
|
|
|
|
if (ifp->if_flags & IFF_UP) {
|
|
s = splimp();
|
|
if_down(ifp);
|
|
if (ifp->if_flags & IFF_RUNNING)
|
|
rtinit(ifp->if_addrlist, (int)SIOCDELRT, RTF_HOST);
|
|
splx(s);
|
|
}
|
|
tp->tun_pgrp = 0;
|
|
selwakeup(&tp->tun_rsel);
|
|
|
|
TUNDEBUG ("%s%d: closed\n", ifp->if_name, ifp->if_unit);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* attach an interface N.B. argument is not same as other drivers
|
|
*/
|
|
static int
|
|
tunattach(unit)
|
|
int unit;
|
|
{
|
|
struct ifnet *ifp = &tunctl[unit].tun_if;
|
|
struct sockaddr_in *sin;
|
|
|
|
ifp->if_unit = unit;
|
|
ifp->if_name = "tun";
|
|
ifp->if_mtu = TUNMTU;
|
|
ifp->if_ioctl = tunioctl;
|
|
ifp->if_output = tunoutput;
|
|
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;
|
|
if_attach(ifp);
|
|
TUNDEBUG("%s%d: tunattach\n", ifp->if_name, ifp->if_unit);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
tuninit(unit)
|
|
int unit;
|
|
{
|
|
struct tunctl *tp = &tunctl[unit];
|
|
struct ifnet *ifp = &tp->tun_if;
|
|
|
|
ifp->if_flags |= IFF_UP | IFF_RUNNING;
|
|
tp->tun_flags |= TUN_IASET;
|
|
TUNDEBUG("%s%d: tuninit\n", ifp->if_name, ifp->if_unit);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Process an ioctl request.
|
|
*/
|
|
int
|
|
tunioctl(ifp, cmd, data, flag)
|
|
struct ifnet *ifp;
|
|
int cmd;
|
|
caddr_t data;
|
|
int flag;
|
|
{
|
|
int error = 0, s;
|
|
struct tunctl *tp = &tunctl[ifp->if_unit];
|
|
|
|
s = splimp();
|
|
switch(cmd) {
|
|
case SIOCSIFADDR:
|
|
tuninit(ifp->if_unit);
|
|
break;
|
|
case SIOCSIFDSTADDR:
|
|
tp->tun_flags |= TUN_DSTADDR;
|
|
TUNDEBUG("%s%d: destination address set\n", ifp->if_name,
|
|
ifp->if_unit);
|
|
break;
|
|
default:
|
|
error = EINVAL;
|
|
}
|
|
splx(s);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* tunoutput - queue packets from higher level ready to put out.
|
|
*/
|
|
int
|
|
tunoutput(ifp, m0, dst)
|
|
struct ifnet *ifp;
|
|
struct mbuf *m0;
|
|
struct sockaddr *dst;
|
|
{
|
|
struct tunctl *tp = &tunctl[ifp->if_unit];
|
|
struct proc *p;
|
|
int s;
|
|
|
|
TUNDEBUG ("%s%d: tunoutput\n", ifp->if_name, ifp->if_unit);
|
|
|
|
switch(dst->sa_family) {
|
|
#ifdef INET
|
|
case AF_INET:
|
|
s = splimp();
|
|
if (IF_QFULL(&ifp->if_snd)) {
|
|
IF_DROP(&ifp->if_snd);
|
|
m_freem(m0);
|
|
splx(s);
|
|
ifp->if_collisions++;
|
|
return (ENOBUFS);
|
|
}
|
|
IF_ENQUEUE(&ifp->if_snd, m0);
|
|
splx(s);
|
|
ifp->if_opackets++;
|
|
break;
|
|
#endif
|
|
default:
|
|
m_freem(m0);
|
|
return EAFNOSUPPORT;
|
|
}
|
|
|
|
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))
|
|
psignal(p, SIGIO);
|
|
}
|
|
selwakeup(&tp->tun_rsel);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* the cdevsw interface is now pretty minimal.
|
|
*/
|
|
int
|
|
tuncioctl(dev, cmd, data, flag)
|
|
dev_t dev;
|
|
int cmd;
|
|
caddr_t data;
|
|
int flag;
|
|
{
|
|
int unit = minor(dev), s;
|
|
struct tunctl *tp = &tunctl[unit];
|
|
|
|
switch (cmd) {
|
|
case TUNSDEBUG:
|
|
tundebug = *(int *)data;
|
|
break;
|
|
case TUNGDEBUG:
|
|
*(int *)data = tundebug;
|
|
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:
|
|
s = splimp();
|
|
if (tp->tun_if.if_snd.ifq_head)
|
|
*(int *)data = tp->tun_if.if_snd.ifq_head->m_len;
|
|
else
|
|
*(int *)data = 0;
|
|
splx(s);
|
|
break;
|
|
case TIOCSPGRP:
|
|
tp->tun_pgrp = *(int *)data;
|
|
break;
|
|
case TIOCGPGRP:
|
|
*(int *)data = tp->tun_pgrp;
|
|
break;
|
|
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.
|
|
*/
|
|
int
|
|
tunread(dev, uio)
|
|
dev_t dev;
|
|
struct uio *uio;
|
|
{
|
|
struct ifnet *ifp = &tp->tun_if;
|
|
struct mbuf *m, *m0;
|
|
struct tunctl *tp = &tunctl[unit];
|
|
int unit = minor(dev);
|
|
int error=0, len, s;
|
|
|
|
TUNDEBUG ("%s%d: read\n", ifp->if_name, ifp->if_unit);
|
|
tp->tun_flags &= ~TUN_RWAIT;
|
|
|
|
s = splimp();
|
|
do {
|
|
IF_DEQUEUE(&ifp->if_snd, m0);
|
|
if (m0 == 0) {
|
|
if (tp->tun_flags & TUN_NBIO) {
|
|
splx(s);
|
|
return EWOULDBLOCK;
|
|
}
|
|
tp->tun_flags |= TUN_RWAIT;
|
|
tsleep((caddr_t)tp, PZERO + 1, "tunread", 0);
|
|
}
|
|
} while (m0 == 0);
|
|
splx(s);
|
|
|
|
while (m0 && uio->uio_resid > 0 && error == 0) {
|
|
len = MIN(uio->uio_resid, m0->m_len);
|
|
if (len == 0)
|
|
break;
|
|
error = uiomove(mtod(m0, caddr_t), len,
|
|
UIO_READ, uio);
|
|
MFREE(m0, m);
|
|
m0 = m;
|
|
}
|
|
|
|
if (m0) {
|
|
TUNDEBUG("Dropping mbuf\n");
|
|
m_freem(m0);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* the cdevsw write interface - an atomic write is a packet - or else!
|
|
*/
|
|
int
|
|
tunwrite(dev, uio)
|
|
int dev;
|
|
struct uio *uio;
|
|
{
|
|
int unit = minor (dev);
|
|
struct ifnet *ifp = &(tunctl[unit].tun_if);
|
|
struct mbuf *top, **mp, *m;
|
|
int error=0, s;
|
|
|
|
TUNDEBUG("%s%d: tunwrite\n", ifp->if_name, ifp->if_unit);
|
|
|
|
if (uio->uio_resid < 0 || uio->uio_resid > TUNMTU) {
|
|
TUNDEBUG("%s%d: len=%d!\n", ifp->if_name, ifp->if_unit,
|
|
uio->uio_resid);
|
|
return EIO;
|
|
}
|
|
top = 0;
|
|
mp = ⊤
|
|
while (error == 0 && uio->uio_resid > 0) {
|
|
MGET(m, M_DONTWAIT, MT_DATA);
|
|
if (m == 0) {
|
|
error = ENOBUFS;
|
|
break;
|
|
}
|
|
m->m_len = MIN(MLEN, uio->uio_resid);
|
|
error = uiomove(mtod(m, caddr_t), m->m_len, UIO_WRITE, uio);
|
|
*mp = m;
|
|
mp = &m->m_next;
|
|
}
|
|
if (error) {
|
|
if (top)
|
|
m_freem(top);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Place interface pointer before the data
|
|
* for the receiving protocol.
|
|
*/
|
|
if (top->m_off <= MMAXOFF &&
|
|
top->m_off >= MMINOFF + sizeof(struct ifnet *)) {
|
|
top->m_off -= sizeof(struct ifnet *);
|
|
top->m_len += sizeof(struct ifnet *);
|
|
} else {
|
|
MGET(m, M_DONTWAIT, MT_HEADER);
|
|
if (m == (struct mbuf *)0)
|
|
return (ENOBUFS);
|
|
m->m_len = sizeof(struct ifnet *);
|
|
m->m_next = top;
|
|
top = m;
|
|
}
|
|
*(mtod(top, struct ifnet **)) = ifp;
|
|
|
|
s = splimp();
|
|
if (IF_QFULL (&ipintrq)) {
|
|
IF_DROP(&ipintrq);
|
|
splx(s);
|
|
ifp->if_collisions++;
|
|
m_freem(top);
|
|
return ENOBUFS;
|
|
}
|
|
IF_ENQUEUE(&ipintrq, top);
|
|
splx(s);
|
|
ifp->if_ipackets++;
|
|
schednetisr(NETISR_IP);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* tunselect - the select 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
|
|
tunselect(dev, rw, p)
|
|
dev_t dev;
|
|
int rw;
|
|
struct proc *p;
|
|
{
|
|
int unit = minor(dev), s;
|
|
struct tunctl *tp = &tunctl[unit];
|
|
struct ifnet *ifp = &tp->tun_if;
|
|
|
|
s = splimp();
|
|
TUNDEBUG("%s%d: tunselect\n", ifp->if_name, ifp->if_unit);
|
|
|
|
switch (rw) {
|
|
case FREAD:
|
|
if (ifp->if_snd.ifq_len > 0) {
|
|
splx(s);
|
|
TUNDEBUG("%s%d: tunselect q=%d\n", ifp->if_name,
|
|
ifp->if_unit, ifp->if_snd.ifq_len);
|
|
return 1;
|
|
}
|
|
selrecord(p, &tp->tun_rsel);
|
|
break;
|
|
case FWRITE:
|
|
splx(s);
|
|
return 1;
|
|
}
|
|
splx(s);
|
|
TUNDEBUG("%s%d: tunselect waiting\n", ifp->if_name, ifp->if_unit);
|
|
return 0;
|
|
}
|
|
#endif NTUN
|