/* $NetBSD: if_tun.c,v 1.14 1994/06/29 06:36:25 cgd Exp $ */
/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (C) 1999-2000 by Maksim Yevmenkin <m_evmenkin@yahoo.com>
* All rights reserved.
* Copyright (c) 2019 Kyle Evans <kevans@FreeBSD.org>
*
* 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 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 AUTHOR 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.
*
* BASED ON:
* -------------------------------------------------------------------------
*
* 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_inet6.h"
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/jail.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/socket.h>
#include <sys/eventhandler.h>
#include <sys/fcntl.h>
#include <sys/filio.h>
#include <sys/sockio.h>
#include <sys/sx.h>
#include <sys/syslog.h>
#include <sys/ttycom.h>
#include <sys/poll.h>
#include <sys/selinfo.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/malloc.h>
#include <sys/random.h>
#include <sys/ctype.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_clone.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/if_vlan_var.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/in.h>
#ifdef INET
#include <netinet/ip.h>
#endif
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#endif
#include <netinet/udp.h>
#include <netinet/tcp.h>
#include <net/bpf.h>
#include <net/if_tap.h>
#include <net/if_tun.h>
#include <dev/virtio/network/virtio_net.h>
#include <sys/queue.h>
#include <sys/condvar.h>
#include <security/mac/mac_framework.h>
struct tuntap_driver;
/*
* tun_list is protected by global tunmtx. Other mutable fields are
* protected by tun->tun_mtx, or by their owning subsystem. tun_dev is
* static for the duration of a tunnel interface.
*/
struct tuntap_softc {
TAILQ_ENTRY(tuntap_softc) tun_list;
struct cdev *tun_alias;
struct cdev *tun_dev;
u_short tun_flags; /* misc flags */
#define TUN_OPEN 0x0001
#define TUN_INITED 0x0002
#define TUN_UNUSED1 0x0008
#define TUN_UNUSED2 0x0010
#define TUN_LMODE 0x0020
#define TUN_RWAIT 0x0040
#define TUN_ASYNC 0x0080
#define TUN_IFHEAD 0x0100
#define TUN_DYING 0x0200
#define TUN_L2 0x0400
#define TUN_VMNET 0x0800
#define TUN_DRIVER_IDENT_MASK (TUN_L2 | TUN_VMNET)
#define TUN_READY (TUN_OPEN | TUN_INITED)
pid_t tun_pid; /* owning pid */
struct ifnet *tun_ifp; /* the interface */
struct sigio *tun_sigio; /* async I/O info */
struct tuntap_driver *tun_drv; /* appropriate driver */
struct selinfo tun_rsel; /* read select */
struct mtx tun_mtx; /* softc field mutex */
struct cv tun_cv; /* for ref'd dev destroy */
struct ether_addr tun_ether; /* remote address */
int tun_busy; /* busy count */
int tun_vhdrlen; /* virtio-net header length */
};
#define TUN2IFP(sc) ((sc)->tun_ifp)
#define TUNDEBUG if (tundebug) if_printf
#define TUN_LOCK(tp) mtx_lock(&(tp)->tun_mtx)
#define TUN_UNLOCK(tp) mtx_unlock(&(tp)->tun_mtx)
#define TUN_LOCK_ASSERT(tp) mtx_assert(&(tp)->tun_mtx, MA_OWNED);
#define TUN_VMIO_FLAG_MASK 0x0fff
/*
* Interface capabilities of a tap device that supports the virtio-net
* header.
*/
#define TAP_VNET_HDR_CAPS (IFCAP_HWCSUM | IFCAP_HWCSUM_IPV6 \
| IFCAP_VLAN_HWCSUM \
| IFCAP_TSO | IFCAP_LRO \
| IFCAP_VLAN_HWTSO)
#define TAP_ALL_OFFLOAD (CSUM_TSO | CSUM_TCP | CSUM_UDP |\
CSUM_TCP_IPV6 | CSUM_UDP_IPV6)
/*
* All mutable global variables in if_tun are locked using tunmtx, with
* the exception of tundebug, which is used unlocked, and the drivers' *clones,
* which are static after setup.
*/
static struct mtx tunmtx;
static eventhandler_tag arrival_tag;
static eventhandler_tag clone_tag;
static const char tunname[] = "tun";
static const char tapname[] = "tap";
static const char vmnetname[] = "vmnet";
static MALLOC_DEFINE(M_TUN, tunname, "Tunnel Interface");
static int tundebug = 0;
static int tundclone = 1;
static int tap_allow_uopen = 0; /* allow user devfs cloning */
static int tapuponopen = 0; /* IFF_UP on open() */
static int tapdclone = 1; /* enable devfs cloning */
static TAILQ_HEAD(,tuntap_softc) tunhead = TAILQ_HEAD_INITIALIZER(tunhead);
SYSCTL_INT(_debug, OID_AUTO, if_tun_debug, CTLFLAG_RW, &tundebug, 0, "");
static struct sx tun_ioctl_sx;
SX_SYSINIT(tun_ioctl_sx, &tun_ioctl_sx, "tun_ioctl");
SYSCTL_DECL(_net_link);
/* tun */
static SYSCTL_NODE(_net_link, OID_AUTO, tun, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"IP tunnel software network interface");
SYSCTL_INT(_net_link_tun, OID_AUTO, devfs_cloning, CTLFLAG_RWTUN, &tundclone, 0,
"Enable legacy devfs interface creation");
/* tap */
static SYSCTL_NODE(_net_link, OID_AUTO, tap, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
"Ethernet tunnel software network interface");
SYSCTL_INT(_net_link_tap, OID_AUTO, user_open, CTLFLAG_RW, &tap_allow_uopen, 0,
"Enable legacy devfs interface creation for all users");
SYSCTL_INT(_net_link_tap, OID_AUTO, up_on_open, CTLFLAG_RW, &tapuponopen, 0,
"Bring interface up when /dev/tap is opened");
SYSCTL_INT(_net_link_tap, OID_AUTO, devfs_cloning, CTLFLAG_RWTUN, &tapdclone, 0,
"Enable legacy devfs interface creation");
SYSCTL_INT(_net_link_tap, OID_AUTO, debug, CTLFLAG_RW, &tundebug, 0, "");
static int tun_create_device(struct tuntap_driver *drv, int unit,
struct ucred *cr, struct cdev **dev, const char *name);
static int tun_busy_locked(struct tuntap_softc *tp);
static void tun_unbusy_locked(struct tuntap_softc *tp);
static int tun_busy(struct tuntap_softc *tp);
static void tun_unbusy(struct tuntap_softc *tp);
static int tuntap_name2info(const char *name, int *unit, int *flags);
static void tunclone(void *arg, struct ucred *cred, char *name,
int namelen, struct cdev **dev);
static void tuncreate(struct cdev *dev);
static void tundtor(void *data);
static void tunrename(void *arg, struct ifnet *ifp);
static int tunifioctl(struct ifnet *, u_long, caddr_t);
static void tuninit(struct ifnet *);
static void tunifinit(void *xtp);
static int tuntapmodevent(module_t, int, void *);
static int tunoutput(struct ifnet *, struct mbuf *,
const struct sockaddr *, struct route *ro);
static void tunstart(struct ifnet *);
static void tunstart_l2(struct ifnet *);
static int tun_clone_match(struct if_clone *ifc, const char *name);
static int tap_clone_match(struct if_clone *ifc, const char *name);
static int vmnet_clone_match(struct if_clone *ifc, const char *name);
static int tun_clone_create(struct if_clone *, char *, size_t, caddr_t);
static int tun_clone_destroy(struct if_clone *, struct ifnet *);
static void tun_vnethdr_set(struct ifnet *ifp, int vhdrlen);
static d_open_t tunopen;
static d_read_t tunread;
static d_write_t tunwrite;
static d_ioctl_t tunioctl;
static d_poll_t tunpoll;
static d_kqfilter_t tunkqfilter;
static int tunkqread(struct knote *, long);
static int tunkqwrite(struct knote *, long);
static void tunkqdetach(struct knote *);
static struct filterops tun_read_filterops = {
.f_isfd = 1,
.f_attach = NULL,
.f_detach = tunkqdetach,
.f_event = tunkqread,
};
static struct filterops tun_write_filterops = {
.f_isfd = 1,
.f_attach = NULL,
.f_detach = tunkqdetach,
.f_event = tunkqwrite,
};
static struct tuntap_driver {
struct cdevsw cdevsw;
int ident_flags;
struct unrhdr *unrhdr;
struct clonedevs *clones;
ifc_match_t *clone_match_fn;
ifc_create_t *clone_create_fn;
ifc_destroy_t *clone_destroy_fn;
} tuntap_drivers[] = {
{
.ident_flags = 0,
.cdevsw = {
.d_version = D_VERSION,
.d_flags = D_NEEDMINOR,
.d_open = tunopen,
.d_read = tunread,
.d_write = tunwrite,
.d_ioctl = tunioctl,
.d_poll = tunpoll,
.d_kqfilter = tunkqfilter,
.d_name = tunname,
},
.clone_match_fn = tun_clone_match,
.clone_create_fn = tun_clone_create,
.clone_destroy_fn = tun_clone_destroy,
},
{
.ident_flags = TUN_L2,
.cdevsw = {
.d_version = D_VERSION,
.d_flags = D_NEEDMINOR,
.d_open = tunopen,
.d_read = tunread,
.d_write = tunwrite,
.d_ioctl = tunioctl,
.d_poll = tunpoll,
.d_kqfilter = tunkqfilter,
.d_name = tapname,
},
.clone_match_fn = tap_clone_match,
.clone_create_fn = tun_clone_create,
.clone_destroy_fn = tun_clone_destroy,
},
{
.ident_flags = TUN_L2 | TUN_VMNET,
.cdevsw = {
.d_version = D_VERSION,
.d_flags = D_NEEDMINOR,
.d_open = tunopen,
.d_read = tunread,
.d_write = tunwrite,
.d_ioctl = tunioctl,
.d_poll = tunpoll,
.d_kqfilter = tunkqfilter,
.d_name = vmnetname,
},
.clone_match_fn = vmnet_clone_match,
.clone_create_fn = tun_clone_create,
.clone_destroy_fn = tun_clone_destroy,
},
};
struct tuntap_driver_cloner {
SLIST_ENTRY(tuntap_driver_cloner) link;
struct tuntap_driver *drv;
struct if_clone *cloner;
};
VNET_DEFINE_STATIC(SLIST_HEAD(, tuntap_driver_cloner), tuntap_driver_cloners) =
SLIST_HEAD_INITIALIZER(tuntap_driver_cloners);
#define V_tuntap_driver_cloners VNET(tuntap_driver_cloners)
/*
* Mechanism for marking a tunnel device as busy so that we can safely do some
* orthogonal operations (such as operations on devices) without racing against
* tun_destroy. tun_destroy will wait on the condvar if we're at all busy or
* open, to be woken up when the condition is alleviated.
*/
static int
tun_busy_locked(struct tuntap_softc *tp)
{
TUN_LOCK_ASSERT(tp);
if ((tp->tun_flags & TUN_DYING) != 0) {
/*
* Perhaps unintuitive, but the device is busy going away.
* Other interpretations of EBUSY from tun_busy make little
* sense, since making a busy device even more busy doesn't
* sound like a problem.
*/
return (EBUSY);
}
++tp->tun_busy;
return (0);
}
static void
tun_unbusy_locked(struct tuntap_softc *tp)
{
TUN_LOCK_ASSERT(tp);
KASSERT(tp->tun_busy != 0, ("tun_unbusy: called for non-busy tunnel"));
--tp->tun_busy;
/* Wake up anything that may be waiting on our busy tunnel. */
if (tp->tun_busy == 0)
cv_broadcast(&tp->tun_cv);
}
static int
tun_busy(struct tuntap_softc *tp)
{
int ret;
TUN_LOCK(tp);
ret = tun_busy_locked(tp);
TUN_UNLOCK(tp);
return (ret);
}
static void
tun_unbusy(struct tuntap_softc *tp)
{
TUN_LOCK(tp);
tun_unbusy_locked(tp);
TUN_UNLOCK(tp);
}
/*
* Sets unit and/or flags given the device name. Must be called with correct
* vnet context.
*/
static int
tuntap_name2info(const char *name, int *outunit, int *outflags)
{
struct tuntap_driver *drv;
struct tuntap_driver_cloner *drvc;
char *dname;
int flags, unit;
bool found;
if (name == NULL)
return (EINVAL);
/*
* Needed for dev_stdclone, but dev_stdclone will not modify, it just
* wants to be able to pass back a char * through the second param. We
* will always set that as NULL here, so we'll fake it.
*/
dname = __DECONST(char *, name);
found = false;
KASSERT(!SLIST_EMPTY(&V_tuntap_driver_cloners),
("tuntap_driver_cloners failed to initialize"));
SLIST_FOREACH(drvc, &V_tuntap_driver_cloners, link) {
KASSERT(drvc->drv != NULL,
("tuntap_driver_cloners entry not properly initialized"));
drv = drvc->drv;
if (strcmp(name, drv->cdevsw.d_name) == 0) {
found = true;
unit = -1;
flags = drv->ident_flags;
break;
}
if (dev_stdclone(dname, NULL, drv->cdevsw.d_name, &unit) == 1) {
found = true;
flags = drv->ident_flags;
break;
}
}
if (!found)
return (ENXIO);
if (outunit != NULL)
*outunit = unit;
if (outflags != NULL)
*outflags = flags;
return (0);
}
/*
* Get driver information from a set of flags specified. Masks the identifying
* part of the flags and compares it against all of the available
* tuntap_drivers. Must be called with correct vnet context.
*/
static struct tuntap_driver *
tuntap_driver_from_flags(int tun_flags)
{
struct tuntap_driver *drv;
struct tuntap_driver_cloner *drvc;
KASSERT(!SLIST_EMPTY(&V_tuntap_driver_cloners),
("tuntap_driver_cloners failed to initialize"));
SLIST_FOREACH(drvc, &V_tuntap_driver_cloners, link) {
KASSERT(drvc->drv != NULL,
("tuntap_driver_cloners entry not properly initialized"));
drv = drvc->drv;
if ((tun_flags & TUN_DRIVER_IDENT_MASK) == drv->ident_flags)
return (drv);
}
return (NULL);
}
static int
tun_clone_match(struct if_clone *ifc, const char *name)
{
int tunflags;
if (tuntap_name2info(name, NULL, &tunflags) == 0) {
if ((tunflags & TUN_L2) == 0)
return (1);
}
return (0);
}
static int
tap_clone_match(struct if_clone *ifc, const char *name)
{
int tunflags;
if (tuntap_name2info(name, NULL, &tunflags) == 0) {
if ((tunflags & (TUN_L2 | TUN_VMNET)) == TUN_L2)
return (1);
}
return (0);
}
static int
vmnet_clone_match(struct if_clone *ifc, const char *name)
{
int tunflags;
if (tuntap_name2info(name, NULL, &tunflags) == 0) {
if ((tunflags & TUN_VMNET) != 0)
return (1);
}
return (0);
}
static int
tun_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
{
struct tuntap_driver *drv;
struct cdev *dev;
int err, i, tunflags, unit;
tunflags = 0;
/* The name here tells us exactly what we're creating */
err = tuntap_name2info(name, &unit, &tunflags);
if (err != 0)
return (err);
drv = tuntap_driver_from_flags(tunflags);
if (drv == NULL)
return (ENXIO);
if (unit != -1) {
/* If this unit number is still available that's okay. */
if (alloc_unr_specific(drv->unrhdr, unit) == -1)
return (EEXIST);
} else {
unit = alloc_unr(drv->unrhdr);
}
snprintf(name, IFNAMSIZ, "%s%d", drv->cdevsw.d_name, unit);
/* find any existing device, or allocate new unit number */
dev = NULL;
i = clone_create(&drv->clones, &drv->cdevsw, &unit, &dev, 0);
/* No preexisting struct cdev *, create one */
if (i != 0)
i = tun_create_device(drv, unit, NULL, &dev, name);
if (i == 0)
tuncreate(dev);
return (i);
}
static void
tunclone(void *arg, struct ucred *cred, char *name, int namelen,
struct cdev **dev)
{
char devname[SPECNAMELEN + 1];
struct tuntap_driver *drv;
int append_unit, i, u, tunflags;
bool mayclone;
if (*dev != NULL)
return;
tunflags = 0;
CURVNET_SET(CRED_TO_VNET(cred));
if (tuntap_name2info(name, &u, &tunflags) != 0)
goto out; /* Not recognized */
if (u != -1 && u > IF_MAXUNIT)
goto out; /* Unit number too high */
mayclone = priv_check_cred(cred, PRIV_NET_IFCREATE) == 0;
if ((tunflags & TUN_L2) != 0) {
/* tap/vmnet allow user open with a sysctl */
mayclone = (mayclone || tap_allow_uopen) && tapdclone;
} else {
mayclone = mayclone && tundclone;
}
/*
* If tun cloning is enabled, only the superuser can create an
* interface.
*/
if (!mayclone)
goto out;
if (u == -1)
append_unit = 1;
else
append_unit = 0;
drv = tuntap_driver_from_flags(tunflags);
if (drv == NULL)
goto out;
/* find any existing device, or allocate new unit number */
i = clone_create(&drv->clones, &drv->cdevsw, &u, dev, 0);
if (i) {
if (append_unit) {
namelen = snprintf(devname, sizeof(devname), "%s%d",
name, u);
name = devname;
}
i = tun_create_device(drv, u, cred, dev, name);
}
if (i == 0)
if_clone_create(name, namelen, NULL);
out:
CURVNET_RESTORE();
}
static void
tun_destroy(struct tuntap_softc *tp)
{
TUN_LOCK(tp);
tp->tun_flags |= TUN_DYING;
if (tp->tun_busy != 0)
cv_wait_unlock(&tp->tun_cv, &tp->tun_mtx);
else
TUN_UNLOCK(tp);
CURVNET_SET(TUN2IFP(tp)->if_vnet);
/* destroy_dev will take care of any alias. */
destroy_dev(tp->tun_dev);
seldrain(&tp->tun_rsel);
knlist_clear(&tp->tun_rsel.si_note, 0);
knlist_destroy(&tp->tun_rsel.si_note);
if ((tp->tun_flags & TUN_L2) != 0) {
ether_ifdetach(TUN2IFP(tp));
} else {
bpfdetach(TUN2IFP(tp));
if_detach(TUN2IFP(tp));
}
sx_xlock(&tun_ioctl_sx);
TUN2IFP(tp)->if_softc = NULL;
sx_xunlock(&tun_ioctl_sx);
free_unr(tp->tun_drv->unrhdr, TUN2IFP(tp)->if_dunit);
if_free(TUN2IFP(tp));
mtx_destroy(&tp->tun_mtx);
cv_destroy(&tp->tun_cv);
free(tp, M_TUN);
CURVNET_RESTORE();
}
static int
tun_clone_destroy(struct if_clone *ifc __unused, struct ifnet *ifp)
{
struct tuntap_softc *tp = ifp->if_softc;
mtx_lock(&tunmtx);
TAILQ_REMOVE(&tunhead, tp, tun_list);
mtx_unlock(&tunmtx);
tun_destroy(tp);
return (0);
}
static void
vnet_tun_init(const void *unused __unused)
{
struct tuntap_driver *drv;
struct tuntap_driver_cloner *drvc;
int i;
for (i = 0; i < nitems(tuntap_drivers); ++i) {
drv = &tuntap_drivers[i];
drvc = malloc(sizeof(*drvc), M_TUN, M_WAITOK | M_ZERO);
drvc->drv = drv;
drvc->cloner = if_clone_advanced(drv->cdevsw.d_name, 0,
drv->clone_match_fn, drv->clone_create_fn,
drv->clone_destroy_fn);
SLIST_INSERT_HEAD(&V_tuntap_driver_cloners, drvc, link);
};
}
VNET_SYSINIT(vnet_tun_init, SI_SUB_PROTO_IF, SI_ORDER_ANY,
vnet_tun_init, NULL);
static void
vnet_tun_uninit(const void *unused __unused)
{
struct tuntap_driver_cloner *drvc;
while (!SLIST_EMPTY(&V_tuntap_driver_cloners)) {
drvc = SLIST_FIRST(&V_tuntap_driver_cloners);
SLIST_REMOVE_HEAD(&V_tuntap_driver_cloners, link);
if_clone_detach(drvc->cloner);
free(drvc, M_TUN);
}
}
VNET_SYSUNINIT(vnet_tun_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY,
vnet_tun_uninit, NULL);
static void
tun_uninit(const void *unused __unused)
{
struct tuntap_driver *drv;
struct tuntap_softc *tp;
int i;
EVENTHANDLER_DEREGISTER(ifnet_arrival_event, arrival_tag);
EVENTHANDLER_DEREGISTER(dev_clone, clone_tag);
drain_dev_clone_events();
mtx_lock(&tunmtx);
while ((tp = TAILQ_FIRST(&tunhead)) != NULL) {
TAILQ_REMOVE(&tunhead, tp, tun_list);
mtx_unlock(&tunmtx);
tun_destroy(tp);
mtx_lock(&tunmtx);
}
mtx_unlock(&tunmtx);
for (i = 0; i < nitems(tuntap_drivers); ++i) {
drv = &tuntap_drivers[i];
delete_unrhdr(drv->unrhdr);
clone_cleanup(&drv->clones);
}
mtx_destroy(&tunmtx);
}
SYSUNINIT(tun_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY, tun_uninit, NULL);
static struct tuntap_driver *
tuntap_driver_from_ifnet(const struct ifnet *ifp)
{
struct tuntap_driver *drv;
int i;
if (ifp == NULL)
return (NULL);
for (i = 0; i < nitems(tuntap_drivers); ++i) {
drv = &tuntap_drivers[i];
if (strcmp(ifp->if_dname, drv->cdevsw.d_name) == 0)
return (drv);
}
return (NULL);
}
static int
tuntapmodevent(module_t mod, int type, void *data)
{
struct tuntap_driver *drv;
int i;
switch (type) {
case MOD_LOAD:
mtx_init(&tunmtx, "tunmtx", NULL, MTX_DEF);
for (i = 0; i < nitems(tuntap_drivers); ++i) {
drv = &tuntap_drivers[i];
clone_setup(&drv->clones);
drv->unrhdr = new_unrhdr(0, IF_MAXUNIT, &tunmtx);
}
arrival_tag = EVENTHANDLER_REGISTER(ifnet_arrival_event,
tunrename, 0, 1000);
if (arrival_tag == NULL)
return (ENOMEM);
clone_tag = EVENTHANDLER_REGISTER(dev_clone, tunclone, 0, 1000);
if (clone_tag == NULL)
return (ENOMEM);
break;
case MOD_UNLOAD:
/* See tun_uninit, so it's done after the vnet_sysuninit() */
break;
default:
return EOPNOTSUPP;
}
return 0;
}
static moduledata_t tuntap_mod = {
"if_tuntap",
tuntapmodevent,
0
};
/* We'll only ever have these two, so no need for a macro. */
static moduledata_t tun_mod = { "if_tun", NULL, 0 };
static moduledata_t tap_mod = { "if_tap", NULL, 0 };
DECLARE_MODULE(if_tuntap, tuntap_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
MODULE_VERSION(if_tuntap, 1);
DECLARE_MODULE(if_tun, tun_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
MODULE_VERSION(if_tun, 1);
DECLARE_MODULE(if_tap, tap_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
MODULE_VERSION(if_tap, 1);
static int
tun_create_device(struct tuntap_driver *drv, int unit, struct ucred *cr,
struct cdev **dev, const char *name)
{
struct make_dev_args args;
struct tuntap_softc *tp;
int error;
tp = malloc(sizeof(*tp), M_TUN, M_WAITOK | M_ZERO);
mtx_init(&tp->tun_mtx, "tun_mtx", NULL, MTX_DEF);
cv_init(&tp->tun_cv, "tun_condvar");
tp->tun_flags = drv->ident_flags;
tp->tun_drv = drv;
make_dev_args_init(&args);
if (cr != NULL)
args.mda_flags = MAKEDEV_REF;
args.mda_devsw = &drv->cdevsw;
args.mda_cr = cr;
args.mda_uid = UID_UUCP;
args.mda_gid = GID_DIALER;
args.mda_mode = 0600;
args.mda_unit = unit;
args.mda_si_drv1 = tp;
error = make_dev_s(&args, dev, "%s", name);
if (error != 0) {
free(tp, M_TUN);
return (error);
}
KASSERT((*dev)->si_drv1 != NULL,
("Failed to set si_drv1 at %s creation", name));
tp->tun_dev = *dev;
knlist_init_mtx(&tp->tun_rsel.si_note, &tp->tun_mtx);
mtx_lock(&tunmtx);
TAILQ_INSERT_TAIL(&tunhead, tp, tun_list);
mtx_unlock(&tunmtx);
return (0);
}
static void
tunstart(struct ifnet *ifp)
{
struct tuntap_softc *tp = ifp->if_softc;
struct mbuf *m;
TUNDEBUG(ifp, "starting\n");
if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
IFQ_LOCK(&ifp->if_snd);
IFQ_POLL_NOLOCK(&ifp->if_snd, m);
if (m == NULL) {
IFQ_UNLOCK(&ifp->if_snd);
return;
}
IFQ_UNLOCK(&ifp->if_snd);
}
TUN_LOCK(tp);
if (tp->tun_flags & TUN_RWAIT) {
tp->tun_flags &= ~TUN_RWAIT;
wakeup(tp);
}
selwakeuppri(&tp->tun_rsel, PZERO + 1);
KNOTE_LOCKED(&tp->tun_rsel.si_note, 0);
if (tp->tun_flags & TUN_ASYNC && tp->tun_sigio) {
TUN_UNLOCK(tp);
pgsigio(&tp->tun_sigio, SIGIO, 0);
} else
TUN_UNLOCK(tp);
}
/*
* tunstart_l2
*
* queue packets from higher level ready to put out
*/
static void
tunstart_l2(struct ifnet *ifp)
{
struct tuntap_softc *tp = ifp->if_softc;
TUNDEBUG(ifp, "starting\n");
/*
* do not junk pending output if we are in VMnet mode.
* XXX: can this do any harm because of queue overflow?
*/
TUN_LOCK(tp);
if (((tp->tun_flags & TUN_VMNET) == 0) &&
((tp->tun_flags & TUN_READY) != TUN_READY)) {
struct mbuf *m;
/* Unlocked read. */
TUNDEBUG(ifp, "not ready, tun_flags = 0x%x\n", tp->tun_flags);
for (;;) {
IF_DEQUEUE(&ifp->if_snd, m);
if (m != NULL) {
m_freem(m);
if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
} else
break;
}
TUN_UNLOCK(tp);
return;
}
ifp->if_drv_flags |= IFF_DRV_OACTIVE;
if (!IFQ_IS_EMPTY(&ifp->if_snd)) {
if (tp->tun_flags & TUN_RWAIT) {
tp->tun_flags &= ~TUN_RWAIT;
wakeup(tp);
}
if ((tp->tun_flags & TUN_ASYNC) && (tp->tun_sigio != NULL)) {
TUN_UNLOCK(tp);
pgsigio(&tp->tun_sigio, SIGIO, 0);
TUN_LOCK(tp);
}
selwakeuppri(&tp->tun_rsel, PZERO+1);
KNOTE_LOCKED(&tp->tun_rsel.si_note, 0);
if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); /* obytes are counted in ether_output */
}
ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
TUN_UNLOCK(tp);
} /* tunstart_l2 */
/* XXX: should return an error code so it can fail. */
static void
tuncreate(struct cdev *dev)
{
struct tuntap_driver *drv;
struct tuntap_softc *tp;
struct ifnet *ifp;
struct ether_addr eaddr;
int iflags;
u_char type;
tp = dev->si_drv1;
KASSERT(tp != NULL,
("si_drv1 should have been initialized at creation"));
drv = tp->tun_drv;
iflags = IFF_MULTICAST;
if ((tp->tun_flags & TUN_L2) != 0) {
type = IFT_ETHER;
iflags |= IFF_BROADCAST | IFF_SIMPLEX;
} else {
type = IFT_PPP;
iflags |= IFF_POINTOPOINT;
}
ifp = tp->tun_ifp = if_alloc(type);
if (ifp == NULL)
panic("%s%d: failed to if_alloc() interface.\n",
drv->cdevsw.d_name, dev2unit(dev));
ifp->if_softc = tp;
if_initname(ifp, drv->cdevsw.d_name, dev2unit(dev));
ifp->if_ioctl = tunifioctl;
ifp->if_flags = iflags;
IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
ifp->if_capabilities |= IFCAP_LINKSTATE;
ifp->if_capenable |= IFCAP_LINKSTATE;
if ((tp->tun_flags & TUN_L2) != 0) {
ifp->if_init = tunifinit;
ifp->if_start = tunstart_l2;
ether_gen_addr(ifp, &eaddr);
ether_ifattach(ifp, eaddr.octet);
} else {
ifp->if_mtu = TUNMTU;
ifp->if_start = tunstart;
ifp->if_output = tunoutput;
ifp->if_snd.ifq_drv_maxlen = 0;
IFQ_SET_READY(&ifp->if_snd);
if_attach(ifp);
bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
}
TUN_LOCK(tp);
tp->tun_flags |= TUN_INITED;
TUN_UNLOCK(tp);
TUNDEBUG(ifp, "interface %s is created, minor = %#x\n",
ifp->if_xname, dev2unit(dev));
}
static void
tunrename(void *arg __unused, struct ifnet *ifp)
{
struct tuntap_softc *tp;
int error;
if ((ifp->if_flags & IFF_RENAMING) == 0)
return;
if (tuntap_driver_from_ifnet(ifp) == NULL)
return;
/*
* We need to grab the ioctl sx long enough to make sure the softc is
* still there. If it is, we can safely try to busy the tun device.
* The busy may fail if the device is currently dying, in which case
* we do nothing. If it doesn't fail, the busy count stops the device
* from dying until we've created the alias (that will then be
* subsequently destroyed).
*/
sx_xlock(&tun_ioctl_sx);
tp = ifp->if_softc;
if (tp == NULL) {
sx_xunlock(&tun_ioctl_sx);
return;
}
error = tun_busy(tp);
sx_xunlock(&tun_ioctl_sx);
if (error != 0)
return;
if (tp->tun_alias != NULL) {
destroy_dev(tp->tun_alias);
tp->tun_alias = NULL;
}
if (strcmp(ifp->if_xname, tp->tun_dev->si_name) == 0)
goto out;
/*
* Failure's ok, aliases are created on a best effort basis. If a
* tun user/consumer decides to rename the interface to conflict with
* another device (non-ifnet) on the system, we will assume they know
* what they are doing. make_dev_alias_p won't touch tun_alias on
* failure, so we use it but ignore the return value.
*/
make_dev_alias_p(MAKEDEV_CHECKNAME, &tp->tun_alias, tp->tun_dev, "%s",
ifp->if_xname);
out:
tun_unbusy(tp);
}
static int
tunopen(struct cdev *dev, int flag, int mode, struct thread *td)
{
struct ifnet *ifp;
struct tuntap_softc *tp;
int error, tunflags;
tunflags = 0;
CURVNET_SET(TD_TO_VNET(td));
error = tuntap_name2info(dev->si_name, NULL, &tunflags);
if (error != 0) {
CURVNET_RESTORE();
return (error); /* Shouldn't happen */
}
tp = dev->si_drv1;
KASSERT(tp != NULL,
("si_drv1 should have been initialized at creation"));
TUN_LOCK(tp);
if ((tp->tun_flags & TUN_INITED) == 0) {
TUN_UNLOCK(tp);
CURVNET_RESTORE();
return (ENXIO);
}
if ((tp->tun_flags & (TUN_OPEN | TUN_DYING)) != 0) {
TUN_UNLOCK(tp);
CURVNET_RESTORE();
return (EBUSY);
}
error = tun_busy_locked(tp);
KASSERT(error == 0, ("Must be able to busy an unopen tunnel"));
ifp = TUN2IFP(tp);
if ((tp->tun_flags & TUN_L2) != 0) {
bcopy(IF_LLADDR(ifp), tp->tun_ether.octet,
sizeof(tp->tun_ether.octet));
ifp->if_drv_flags |= IFF_DRV_RUNNING;
ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
if (tapuponopen)
ifp->if_flags |= IFF_UP;
}
tp->tun_pid = td->td_proc->p_pid;
tp->tun_flags |= TUN_OPEN;
if_link_state_change(ifp, LINK_STATE_UP);
TUNDEBUG(ifp, "open\n");
TUN_UNLOCK(tp);
/*
* This can fail with either ENOENT or EBUSY. This is in the middle of
* d_open, so ENOENT should not be possible. EBUSY is possible, but
* the only cdevpriv dtor being set will be tundtor and the softc being
* passed is constant for a given cdev. We ignore the possible error
* because of this as either "unlikely" or "not actually a problem."
*/
(void)devfs_set_cdevpriv(tp, tundtor);
CURVNET_RESTORE();
return (0);
}
/*
* tundtor - tear down the device - mark i/f down & delete
* routing info
*/
static void
tundtor(void *data)
{
struct proc *p;
struct tuntap_softc *tp;
struct ifnet *ifp;
bool l2tun;
tp = data;
p = curproc;
ifp = TUN2IFP(tp);
TUN_LOCK(tp);
/*
* Realistically, we can't be obstinate here. This only means that the
* tuntap device was closed out of order, and the last closer wasn't the
* controller. These are still good to know about, though, as software
* should avoid multiple processes with a tuntap device open and
* ill-defined transfer of control (e.g., handoff, TUNSIFPID, close in
* parent).
*/
if (p->p_pid != tp->tun_pid) {
log(LOG_INFO,
"pid %d (%s), %s: tun/tap protocol violation, non-controlling process closed last.\n",
p->p_pid, p->p_comm, tp->tun_dev->si_name);
}
/*
* junk all pending output
*/
CURVNET_SET(ifp->if_vnet);
l2tun = false;
if ((tp->tun_flags & TUN_L2) != 0) {
l2tun = true;
IF_DRAIN(&ifp->if_snd);
} else {
IFQ_PURGE(&ifp->if_snd);
}
/* For vmnet, we won't do most of the address/route bits */
if ((tp->tun_flags & TUN_VMNET) != 0 ||
(l2tun && (ifp->if_flags & IFF_LINK0) != 0))
goto out;
if (ifp->if_flags & IFF_UP) {
TUN_UNLOCK(tp);
if_down(ifp);
TUN_LOCK(tp);
}
/* Delete all addresses and routes which reference this interface. */
if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
TUN_UNLOCK(tp);
if_purgeaddrs(ifp);
TUN_LOCK(tp);
}
out:
if_link_state_change(ifp, LINK_STATE_DOWN);
CURVNET_RESTORE();
funsetown(&tp->tun_sigio);
selwakeuppri(&tp->tun_rsel, PZERO + 1);
KNOTE_LOCKED(&tp->tun_rsel.si_note, 0);
TUNDEBUG (ifp, "closed\n");
tp->tun_flags &= ~TUN_OPEN;
tp->tun_pid = 0;
tun_vnethdr_set(ifp, 0);
tun_unbusy_locked(tp);
TUN_UNLOCK(tp);
}
static void
tuninit(struct ifnet *ifp)
{
struct tuntap_softc *tp = ifp->if_softc;
TUNDEBUG(ifp, "tuninit\n");
TUN_LOCK(tp);
ifp->if_drv_flags |= IFF_DRV_RUNNING;
if ((tp->tun_flags & TUN_L2) == 0) {
ifp->if_flags |= IFF_UP;
getmicrotime(&ifp->if_lastchange);
TUN_UNLOCK(tp);
} else {
ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
TUN_UNLOCK(tp);
/* attempt to start output */
tunstart_l2(ifp);
}
}
/*
* Used only for l2 tunnel.
*/
static void
tunifinit(void *xtp)
{
struct tuntap_softc *tp;
tp = (struct tuntap_softc *)xtp;
tuninit(tp->tun_ifp);
}
/*
* To be called under TUN_LOCK. Update ifp->if_hwassist according to the
* current value of ifp->if_capenable.
*/
static void
tun_caps_changed(struct ifnet *ifp)
{
uint64_t hwassist = 0;
TUN_LOCK_ASSERT((struct tuntap_softc *)ifp->if_softc);
if (ifp->if_capenable & IFCAP_TXCSUM)
hwassist |= CSUM_TCP | CSUM_UDP;
if (ifp->if_capenable & IFCAP_TXCSUM_IPV6)
hwassist |= CSUM_TCP_IPV6
| CSUM_UDP_IPV6;
if (ifp->if_capenable & IFCAP_TSO4)
hwassist |= CSUM_IP_TSO;
if (ifp->if_capenable & IFCAP_TSO6)
hwassist |= CSUM_IP6_TSO;
ifp->if_hwassist = hwassist;
}
/*
* To be called under TUN_LOCK. Update tp->tun_vhdrlen and adjust
* if_capabilities and if_capenable as needed.
*/
static void
tun_vnethdr_set(struct ifnet *ifp, int vhdrlen)
{
struct tuntap_softc *tp = ifp->if_softc;
TUN_LOCK_ASSERT(tp);
if (tp->tun_vhdrlen == vhdrlen)
return;
/*
* Update if_capabilities to reflect the
* functionalities offered by the virtio-net
* header.
*/
if (vhdrlen != 0)
ifp->if_capabilities |=
TAP_VNET_HDR_CAPS;
else
ifp->if_capabilities &=
~TAP_VNET_HDR_CAPS;
/*
* Disable any capabilities that we don't
* support anymore.
*/
ifp->if_capenable &= ifp->if_capabilities;
tun_caps_changed(ifp);
tp->tun_vhdrlen = vhdrlen;
TUNDEBUG(ifp, "vnet_hdr_len=%d, if_capabilities=%x\n",
vhdrlen, ifp->if_capabilities);
}
/*
* Process an ioctl request.
*/
static int
tunifioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
struct ifreq *ifr = (struct ifreq *)data;
struct tuntap_softc *tp;
struct ifstat *ifs;
struct ifmediareq *ifmr;
int dummy, error = 0;
bool l2tun;
ifmr = NULL;
sx_xlock(&tun_ioctl_sx);
tp = ifp->if_softc;
if (tp == NULL) {
error = ENXIO;
goto bad;
}
l2tun = (tp->tun_flags & TUN_L2) != 0;
switch(cmd) {
case SIOCGIFSTATUS:
ifs = (struct ifstat *)data;
TUN_LOCK(tp);
if (tp->tun_pid)
snprintf(ifs->ascii, sizeof(ifs->ascii),
"\tOpened by PID %d\n", tp->tun_pid);
else
ifs->ascii[0] = '\0';
TUN_UNLOCK(tp);
break;
case SIOCSIFADDR:
if (l2tun)
error = ether_ioctl(ifp, cmd, data);
else
tuninit(ifp);
if (error == 0)
TUNDEBUG(ifp, "address set\n");
break;
case SIOCSIFMTU:
ifp->if_mtu = ifr->ifr_mtu;
TUNDEBUG(ifp, "mtu set\n");
break;
case SIOCSIFFLAGS:
case SIOCADDMULTI:
case SIOCDELMULTI:
break;
case SIOCGIFMEDIA:
if (!l2tun) {
error = EINVAL;
break;
}
ifmr = (struct ifmediareq *)data;
dummy = ifmr->ifm_count;
ifmr->ifm_count = 1;
ifmr->ifm_status = IFM_AVALID;
ifmr->ifm_active = IFM_ETHER;
if (tp->tun_flags & TUN_OPEN)
ifmr->ifm_status |= IFM_ACTIVE;
ifmr->ifm_current = ifmr->ifm_active;
if (dummy >= 1) {
int media = IFM_ETHER;
error = copyout(&media, ifmr->ifm_ulist, sizeof(int));
}
break;
case SIOCSIFCAP:
TUN_LOCK(tp);
ifp->if_capenable = ifr->ifr_reqcap;
tun_caps_changed(ifp);
TUN_UNLOCK(tp);
VLAN_CAPABILITIES(ifp);
break;
default:
if (l2tun) {
error = ether_ioctl(ifp, cmd, data);
} else {
error = EINVAL;
}
}
bad:
sx_xunlock(&tun_ioctl_sx);
return (error);
}
/*
* tunoutput - queue packets from higher level ready to put out.
*/
static int
tunoutput(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst,
struct route *ro)
{
struct tuntap_softc *tp = ifp->if_softc;
u_short cached_tun_flags;
int error;
u_int32_t af;
TUNDEBUG (ifp, "tunoutput\n");
#ifdef MAC
error = mac_ifnet_check_transmit(ifp, m0);
if (error) {
m_freem(m0);
return (error);
}
#endif
/* Could be unlocked read? */
TUN_LOCK(tp);
cached_tun_flags = tp->tun_flags;
TUN_UNLOCK(tp);
if ((cached_tun_flags & TUN_READY) != TUN_READY) {
TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags);
m_freem (m0);
return (EHOSTDOWN);
}
if ((ifp->if_flags & IFF_UP) != IFF_UP) {
m_freem (m0);
return (EHOSTDOWN);
}
/* BPF writes need to be handled specially. */
if (dst->sa_family == AF_UNSPEC)
bcopy(dst->sa_data, &af, sizeof(af));
else
af = dst->sa_family;
if (bpf_peers_present(ifp->if_bpf))
bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m0);
/* prepend sockaddr? this may abort if the mbuf allocation fails */
if (cached_tun_flags & TUN_LMODE) {
/* allocate space for sockaddr */
M_PREPEND(m0, dst->sa_len, M_NOWAIT);
/* if allocation failed drop packet */
if (m0 == NULL) {
if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
return (ENOBUFS);
} else {
bcopy(dst, m0->m_data, dst->sa_len);
}
}
if (cached_tun_flags & TUN_IFHEAD) {
/* Prepend the address family */
M_PREPEND(m0, 4, M_NOWAIT);
/* if allocation failed drop packet */
if (m0 == NULL) {
if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
return (ENOBUFS);
} else
*(u_int32_t *)m0->m_data = htonl(af);
} else {
#ifdef INET
if (af != AF_INET)
#endif
{
m_freem(m0);
return (EAFNOSUPPORT);
}
}
error = (ifp->if_transmit)(ifp, m0);
if (error)
return (ENOBUFS);
if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
return (0);
}
/*
* the cdevsw interface is now pretty minimal.
*/
static int
tunioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag,
struct thread *td)
{
struct ifreq ifr, *ifrp;
struct tuntap_softc *tp = dev->si_drv1;
struct ifnet *ifp = TUN2IFP(tp);
struct tuninfo *tunp;
int error, iflags, ival;
bool l2tun;
l2tun = (tp->tun_flags & TUN_L2) != 0;
if (l2tun) {
/* tap specific ioctls */
switch(cmd) {
/* VMware/VMnet port ioctl's */
#if defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD5) || \
defined(COMPAT_FREEBSD4)
case _IO('V', 0):
ival = IOCPARM_IVAL(data);
data = (caddr_t)&ival;
/* FALLTHROUGH */
#endif
case VMIO_SIOCSIFFLAGS: /* VMware/VMnet SIOCSIFFLAGS */
iflags = *(int *)data;
iflags &= TUN_VMIO_FLAG_MASK;
iflags &= ~IFF_CANTCHANGE;
iflags |= IFF_UP;
TUN_LOCK(tp);
ifp->if_flags = iflags |
(ifp->if_flags & IFF_CANTCHANGE);
TUN_UNLOCK(tp);
return (0);
case SIOCGIFADDR: /* get MAC address of the remote side */
TUN_LOCK(tp);
bcopy(&tp->tun_ether.octet, data,
sizeof(tp->tun_ether.octet));
TUN_UNLOCK(tp);
return (0);
case SIOCSIFADDR: /* set MAC address of the remote side */
TUN_LOCK(tp);
bcopy(data, &tp->tun_ether.octet,
sizeof(tp->tun_ether.octet));
TUN_UNLOCK(tp);
return (0);
case TAPSVNETHDR:
ival = *(int *)data;
if (ival != 0 &&
ival != sizeof(struct virtio_net_hdr) &&
ival != sizeof(struct virtio_net_hdr_mrg_rxbuf)) {
return (EINVAL);
}
TUN_LOCK(tp);
tun_vnethdr_set(ifp, ival);
TUN_UNLOCK(tp);
return (0);
case TAPGVNETHDR:
TUN_LOCK(tp);
*(int *)data = tp->tun_vhdrlen;
TUN_UNLOCK(tp);
return (0);
}
/* Fall through to the common ioctls if unhandled */
} else {
switch (cmd) {
case TUNSLMODE:
TUN_LOCK(tp);
if (*(int *)data) {
tp->tun_flags |= TUN_LMODE;
tp->tun_flags &= ~TUN_IFHEAD;
} else
tp->tun_flags &= ~TUN_LMODE;
TUN_UNLOCK(tp);
return (0);
case TUNSIFHEAD:
TUN_LOCK(tp);
if (*(int *)data) {
tp->tun_flags |= TUN_IFHEAD;
tp->tun_flags &= ~TUN_LMODE;
} else
tp->tun_flags &= ~TUN_IFHEAD;
TUN_UNLOCK(tp);
return (0);
case TUNGIFHEAD:
TUN_LOCK(tp);
*(int *)data = (tp->tun_flags & TUN_IFHEAD) ? 1 : 0;
TUN_UNLOCK(tp);
return (0);
case TUNSIFMODE:
/* deny this if UP */
if (TUN2IFP(tp)->if_flags & IFF_UP)
return (EBUSY);
switch (*(int *)data & ~IFF_MULTICAST) {
case IFF_POINTOPOINT:
case IFF_BROADCAST:
TUN_LOCK(tp);
TUN2IFP(tp)->if_flags &=
~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST);
TUN2IFP(tp)->if_flags |= *(int *)data;
TUN_UNLOCK(tp);
break;
default:
return (EINVAL);
}
return (0);
case TUNSIFPID:
TUN_LOCK(tp);
tp->tun_pid = curthread->td_proc->p_pid;
TUN_UNLOCK(tp);
return (0);
}
/* Fall through to the common ioctls if unhandled */
}
switch (cmd) {
case TUNGIFNAME:
ifrp = (struct ifreq *)data;
strlcpy(ifrp->ifr_name, TUN2IFP(tp)->if_xname, IFNAMSIZ);
return (0);
case TUNSIFINFO:
tunp = (struct tuninfo *)data;
if (TUN2IFP(tp)->if_type != tunp->type)
return (EPROTOTYPE);
TUN_LOCK(tp);
if (TUN2IFP(tp)->if_mtu != tunp->mtu) {
strlcpy(ifr.ifr_name, if_name(TUN2IFP(tp)), IFNAMSIZ);
ifr.ifr_mtu = tunp->mtu;
CURVNET_SET(TUN2IFP(tp)->if_vnet);
error = ifhwioctl(SIOCSIFMTU, TUN2IFP(tp),
(caddr_t)&ifr, td);
CURVNET_RESTORE();
if (error) {
TUN_UNLOCK(tp);
return (error);
}
}
TUN2IFP(tp)->if_baudrate = tunp->baudrate;
TUN_UNLOCK(tp);
break;
case TUNGIFINFO:
tunp = (struct tuninfo *)data;
TUN_LOCK(tp);
tunp->mtu = TUN2IFP(tp)->if_mtu;
tunp->type = TUN2IFP(tp)->if_type;
tunp->baudrate = TUN2IFP(tp)->if_baudrate;
TUN_UNLOCK(tp);
break;
case TUNSDEBUG:
tundebug = *(int *)data;
break;
case TUNGDEBUG:
*(int *)data = tundebug;
break;
case FIONBIO:
break;
case FIOASYNC:
TUN_LOCK(tp);
if (*(int *)data)
tp->tun_flags |= TUN_ASYNC;
else
tp->tun_flags &= ~TUN_ASYNC;
TUN_UNLOCK(tp);
break;
case FIONREAD:
if (!IFQ_IS_EMPTY(&TUN2IFP(tp)->if_snd)) {
struct mbuf *mb;
IFQ_LOCK(&TUN2IFP(tp)->if_snd);
IFQ_POLL_NOLOCK(&TUN2IFP(tp)->if_snd, mb);
for (*(int *)data = 0; mb != NULL; mb = mb->m_next)
*(int *)data += mb->m_len;
IFQ_UNLOCK(&TUN2IFP(tp)->if_snd);
} else
*(int *)data = 0;
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(struct cdev *dev, struct uio *uio, int flag)
{
struct tuntap_softc *tp = dev->si_drv1;
struct ifnet *ifp = TUN2IFP(tp);
struct mbuf *m;
size_t len;
int error = 0;
TUNDEBUG (ifp, "read\n");
TUN_LOCK(tp);
if ((tp->tun_flags & TUN_READY) != TUN_READY) {
TUN_UNLOCK(tp);
TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags);
return (EHOSTDOWN);
}
tp->tun_flags &= ~TUN_RWAIT;
for (;;) {
IFQ_DEQUEUE(&ifp->if_snd, m);
if (m != NULL)
break;
if (flag & O_NONBLOCK) {
TUN_UNLOCK(tp);
return (EWOULDBLOCK);
}
tp->tun_flags |= TUN_RWAIT;
error = mtx_sleep(tp, &tp->tun_mtx, PCATCH | (PZERO + 1),
"tunread", 0);
if (error != 0) {
TUN_UNLOCK(tp);
return (error);
}
}
TUN_UNLOCK(tp);
if ((tp->tun_flags & TUN_L2) != 0)
BPF_MTAP(ifp, m);
len = min(tp->tun_vhdrlen, uio->uio_resid);
if (len > 0) {
struct virtio_net_hdr_mrg_rxbuf vhdr;
bzero(&vhdr, sizeof(vhdr));
if (m->m_pkthdr.csum_flags & TAP_ALL_OFFLOAD) {
m = virtio_net_tx_offload(ifp, m, false, &vhdr.hdr);
}
TUNDEBUG(ifp, "txvhdr: f %u, gt %u, hl %u, "
"gs %u, cs %u, co %u\n", vhdr.hdr.flags,
vhdr.hdr.gso_type, vhdr.hdr.hdr_len,
vhdr.hdr.gso_size, vhdr.hdr.csum_start,
vhdr.hdr.csum_offset);
error = uiomove(&vhdr, len, uio);
}
while (m && uio->uio_resid > 0 && error == 0) {
len = min(uio->uio_resid, m->m_len);
if (len != 0)
error = uiomove(mtod(m, void *), len, uio);
m = m_free(m);
}
if (m) {
TUNDEBUG(ifp, "Dropping mbuf\n");
m_freem(m);
}
return (error);
}
static int
tunwrite_l2(struct tuntap_softc *tp, struct mbuf *m,
struct virtio_net_hdr_mrg_rxbuf *vhdr)
{
struct epoch_tracker et;
struct ether_header *eh;
struct ifnet *ifp;
ifp = TUN2IFP(tp);
/*
* Only pass a unicast frame to ether_input(), if it would
* actually have been received by non-virtual hardware.
*/
if (m->m_len < sizeof(struct ether_header)) {
m_freem(m);
return (0);
}
eh = mtod(m, struct ether_header *);
if (eh && (ifp->if_flags & IFF_PROMISC) == 0 &&
!ETHER_IS_MULTICAST(eh->ether_dhost) &&
bcmp(eh->ether_dhost, IF_LLADDR(ifp), ETHER_ADDR_LEN) != 0) {
m_freem(m);
return (0);
}
if (vhdr != NULL && virtio_net_rx_csum(m, &vhdr->hdr)) {
m_freem(m);
return (0);
}
/* Pass packet up to parent. */
CURVNET_SET(ifp->if_vnet);
NET_EPOCH_ENTER(et);
(*ifp->if_input)(ifp, m);
NET_EPOCH_EXIT(et);
CURVNET_RESTORE();
/* ibytes are counted in parent */
if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
return (0);
}
static int
tunwrite_l3(struct tuntap_softc *tp, struct mbuf *m)
{
struct epoch_tracker et;
struct ifnet *ifp;
int family, isr;
ifp = TUN2IFP(tp);
/* Could be unlocked read? */
TUN_LOCK(tp);
if (tp->tun_flags & TUN_IFHEAD) {
TUN_UNLOCK(tp);
if (m->m_len < sizeof(family) &&
(m = m_pullup(m, sizeof(family))) == NULL)
return (ENOBUFS);
family = ntohl(*mtod(m, u_int32_t *));
m_adj(m, sizeof(family));
} else {
TUN_UNLOCK(tp);
family = AF_INET;
}
BPF_MTAP2(ifp, &family, sizeof(family), m);
switch (family) {
#ifdef INET
case AF_INET:
isr = NETISR_IP;
break;
#endif
#ifdef INET6
case AF_INET6:
isr = NETISR_IPV6;
break;
#endif
default:
m_freem(m);
return (EAFNOSUPPORT);
}
random_harvest_queue(m, sizeof(*m), RANDOM_NET_TUN);
if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len);
if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
CURVNET_SET(ifp->if_vnet);
M_SETFIB(m, ifp->if_fib);
NET_EPOCH_ENTER(et);
netisr_dispatch(isr, m);
NET_EPOCH_EXIT(et);
CURVNET_RESTORE();
return (0);
}
/*
* the cdevsw write interface - an atomic write is a packet - or else!
*/
static int
tunwrite(struct cdev *dev, struct uio *uio, int flag)
{
struct virtio_net_hdr_mrg_rxbuf vhdr;
struct tuntap_softc *tp;
struct ifnet *ifp;
struct mbuf *m;
uint32_t mru;
int align, vhdrlen, error;
bool l2tun;
tp = dev->si_drv1;
ifp = TUN2IFP(tp);
TUNDEBUG(ifp, "tunwrite\n");
if ((ifp->if_flags & IFF_UP) != IFF_UP)
/* ignore silently */
return (0);
if (uio->uio_resid == 0)
return (0);
l2tun = (tp->tun_flags & TUN_L2) != 0;
mru = l2tun ? TAPMRU : TUNMRU;
vhdrlen = tp->tun_vhdrlen;
align = 0;
if (l2tun) {
align = ETHER_ALIGN;
mru += vhdrlen;
} else if ((tp->tun_flags & TUN_IFHEAD) != 0)
mru += sizeof(uint32_t); /* family */
if (uio->uio_resid < 0 || uio->uio_resid > mru) {
TUNDEBUG(ifp, "len=%zd!\n", uio->uio_resid);
return (EIO);
}
if (vhdrlen > 0) {
error = uiomove(&vhdr, vhdrlen, uio);
if (error != 0)
return (error);
TUNDEBUG(ifp, "txvhdr: f %u, gt %u, hl %u, "
"gs %u, cs %u, co %u\n", vhdr.hdr.flags,
vhdr.hdr.gso_type, vhdr.hdr.hdr_len,
vhdr.hdr.gso_size, vhdr.hdr.csum_start,
vhdr.hdr.csum_offset);
}
if ((m = m_uiotombuf(uio, M_NOWAIT, 0, align, M_PKTHDR)) == NULL) {
if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
return (ENOBUFS);
}
m->m_pkthdr.rcvif = ifp;
#ifdef MAC
mac_ifnet_create_mbuf(ifp, m);
#endif
if (l2tun)
return (tunwrite_l2(tp, m, vhdrlen > 0 ? &vhdr : NULL));
return (tunwrite_l3(tp, m));
}
/*
* 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(struct cdev *dev, int events, struct thread *td)
{
struct tuntap_softc *tp = dev->si_drv1;
struct ifnet *ifp = TUN2IFP(tp);
int revents = 0;
TUNDEBUG(ifp, "tunpoll\n");
if (events & (POLLIN | POLLRDNORM)) {
IFQ_LOCK(&ifp->if_snd);
if (!IFQ_IS_EMPTY(&ifp->if_snd)) {
TUNDEBUG(ifp, "tunpoll q=%d\n", ifp->if_snd.ifq_len);
revents |= events & (POLLIN | POLLRDNORM);
} else {
TUNDEBUG(ifp, "tunpoll waiting\n");
selrecord(td, &tp->tun_rsel);
}
IFQ_UNLOCK(&ifp->if_snd);
}
revents |= events & (POLLOUT | POLLWRNORM);
return (revents);
}
/*
* tunkqfilter - support for the kevent() system call.
*/
static int
tunkqfilter(struct cdev *dev, struct knote *kn)
{
struct tuntap_softc *tp = dev->si_drv1;
struct ifnet *ifp = TUN2IFP(tp);
switch(kn->kn_filter) {
case EVFILT_READ:
TUNDEBUG(ifp, "%s kqfilter: EVFILT_READ, minor = %#x\n",
ifp->if_xname, dev2unit(dev));
kn->kn_fop = &tun_read_filterops;
break;
case EVFILT_WRITE:
TUNDEBUG(ifp, "%s kqfilter: EVFILT_WRITE, minor = %#x\n",
ifp->if_xname, dev2unit(dev));
kn->kn_fop = &tun_write_filterops;
break;
default:
TUNDEBUG(ifp, "%s kqfilter: invalid filter, minor = %#x\n",
ifp->if_xname, dev2unit(dev));
return(EINVAL);
}
kn->kn_hook = tp;
knlist_add(&tp->tun_rsel.si_note, kn, 0);
return (0);
}
/*
* Return true of there is data in the interface queue.
*/
static int
tunkqread(struct knote *kn, long hint)
{
int ret;
struct tuntap_softc *tp = kn->kn_hook;
struct cdev *dev = tp->tun_dev;
struct ifnet *ifp = TUN2IFP(tp);
if ((kn->kn_data = ifp->if_snd.ifq_len) > 0) {
TUNDEBUG(ifp,
"%s have data in the queue. Len = %d, minor = %#x\n",
ifp->if_xname, ifp->if_snd.ifq_len, dev2unit(dev));
ret = 1;
} else {
TUNDEBUG(ifp,
"%s waiting for data, minor = %#x\n", ifp->if_xname,
dev2unit(dev));
ret = 0;
}
return (ret);
}
/*
* Always can write, always return MTU in kn->data.
*/
static int
tunkqwrite(struct knote *kn, long hint)
{
struct tuntap_softc *tp = kn->kn_hook;
struct ifnet *ifp = TUN2IFP(tp);
kn->kn_data = ifp->if_mtu;
return (1);
}
static void
tunkqdetach(struct knote *kn)
{
struct tuntap_softc *tp = kn->kn_hook;
knlist_remove(&tp->tun_rsel.si_note, kn, 0);
}
