diff options
Diffstat (limited to 'sys/net/if_tuntap.c')
| -rw-r--r-- | sys/net/if_tuntap.c | 2141 |
1 files changed, 2141 insertions, 0 deletions
diff --git a/sys/net/if_tuntap.c b/sys/net/if_tuntap.c new file mode 100644 index 000000000000..56bb90cce9bc --- /dev/null +++ b/sys/net/if_tuntap.c @@ -0,0 +1,2141 @@ +/* $NetBSD: if_tun.c,v 1.14 1994/06/29 06:36:25 cgd Exp $ */ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * 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. + */ + +#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 <sys/osd.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_private.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 <netinet/tcp_lro.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_TRANSIENT 0x1000 + +#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 */ + struct lro_ctrl tun_lro; /* for TCP LRO */ + bool tun_lro_ready; /* TCP LRO initialized */ +}; +#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 int tuntap_osd_jail_slot; +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, + struct ifc_data *, struct ifnet **); +static int tun_clone_destroy(struct if_clone *, struct ifnet *, uint32_t); +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 const struct filterops tun_read_filterops = { + .f_isfd = 1, + .f_attach = NULL, + .f_detach = tunkqdetach, + .f_event = tunkqread, + .f_copy = knote_triv_copy, +}; + +static const struct filterops tun_write_filterops = { + .f_isfd = 1, + .f_attach = NULL, + .f_detach = tunkqdetach, + .f_event = tunkqwrite, + .f_copy = knote_triv_copy, +}; + +static struct tuntap_driver { + struct cdevsw cdevsw; + int ident_flags; + struct unrhdr *unrhdr; + struct clonedevs *clones; + ifc_match_f *clone_match_fn; + ifc_create_f *clone_create_fn; + ifc_destroy_f *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, + }, +}; +#define NDRV nitems(tuntap_drivers) + +VNET_DEFINE_STATIC(struct if_clone *, tuntap_driver_cloners[NDRV]); +#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; + 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; + + for (u_int i = 0; i < NDRV; i++) { + drv = &tuntap_drivers[i]; + + 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); +} + +static struct if_clone * +tuntap_cloner_from_flags(int tun_flags) +{ + + for (u_int i = 0; i < NDRV; i++) + if ((tun_flags & TUN_DRIVER_IDENT_MASK) == + tuntap_drivers[i].ident_flags) + return (V_tuntap_driver_cloners[i]); + + return (NULL); +} + +/* + * 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. + */ +static struct tuntap_driver * +tuntap_driver_from_flags(int tun_flags) +{ + + for (u_int i = 0; i < NDRV; i++) + if ((tun_flags & TUN_DRIVER_IDENT_MASK) == + tuntap_drivers[i].ident_flags) + return (&tuntap_drivers[i]); + + 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); +} + +/* + * Create a clone via the ifnet cloning mechanism. Note that this is invoked + * indirectly by tunclone() below. + */ +static int +tun_clone_create(struct if_clone *ifc, char *name, size_t len, + struct ifc_data *ifd, struct ifnet **ifpp) +{ + 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) { + struct tuntap_softc *tp; + + tuncreate(dev); + tp = dev->si_drv1; + *ifpp = tp->tun_ifp; + } + + return (i); +} + +/* + * Create a clone via devfs access. + */ +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); + } else { + /* Consumed by the dev_clone invoker. */ + dev_ref(*dev); + } + if (i == 0) + if_clone_create(name, namelen, NULL); +out: + CURVNET_RESTORE(); +} + +static int +tun_destroy(struct tuntap_softc *tp, bool may_intr) +{ + int error; + + TUN_LOCK(tp); + + /* + * Transient tunnels may have set TUN_DYING if we're being destroyed as + * a result of the last close, which we'll allow. + */ + MPASS((tp->tun_flags & (TUN_DYING | TUN_TRANSIENT)) != TUN_DYING); + tp->tun_flags |= TUN_DYING; + error = 0; + while (tp->tun_busy != 0) { + if (may_intr) + error = cv_wait_sig(&tp->tun_cv, &tp->tun_mtx); + else + cv_wait(&tp->tun_cv, &tp->tun_mtx); + if (error != 0) { + tp->tun_flags &= ~TUN_DYING; + TUN_UNLOCK(tp); + return (error); + } + } + TUN_UNLOCK(tp); + + CURVNET_SET(TUN2IFP(tp)->if_vnet); + + mtx_lock(&tunmtx); + TAILQ_REMOVE(&tunhead, tp, tun_list); + mtx_unlock(&tunmtx); + + /* 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(); + + return (0); +} + +static int +tun_clone_destroy(struct if_clone *ifc __unused, struct ifnet *ifp, uint32_t flags) +{ + struct tuntap_softc *tp = ifp->if_softc; + + return (tun_destroy(tp, true)); +} + +static void +vnet_tun_init(const void *unused __unused) +{ + + for (u_int i = 0; i < NDRV; ++i) { + struct if_clone_addreq req = { + .match_f = tuntap_drivers[i].clone_match_fn, + .create_f = tuntap_drivers[i].clone_create_fn, + .destroy_f = tuntap_drivers[i].clone_destroy_fn, + }; + V_tuntap_driver_cloners[i] = + ifc_attach_cloner(tuntap_drivers[i].cdevsw.d_name, &req); + }; +} +VNET_SYSINIT(vnet_tun_init, SI_SUB_PROTO_IF, SI_ORDER_ANY, + vnet_tun_init, 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); + + CURVNET_SET(vnet0); + for (u_int i = 0; i < NDRV; i++) { + if_clone_detach(V_tuntap_driver_cloners[i]); + V_tuntap_driver_cloners[i] = NULL; + } + CURVNET_RESTORE(); + + if (tuntap_osd_jail_slot != 0) + osd_jail_deregister(tuntap_osd_jail_slot); + + mtx_lock(&tunmtx); + while ((tp = TAILQ_FIRST(&tunhead)) != NULL) { + mtx_unlock(&tunmtx); + /* tun_destroy() will remove it from the tailq. */ + tun_destroy(tp, false); + 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); +} + +/* + * Remove devices that were created by devfs cloning, as they hold references + * which prevent the prison from collapsing, in which state VNET sysuninits will + * not be invoked. + */ +static int +tuntap_prison_remove(void *obj, void *data __unused) +{ +#ifdef VIMAGE + struct prison *pr; + + pr = obj; + if (prison_owns_vnet(pr)) { + CURVNET_SET(pr->pr_vnet); + for (u_int i = 0; i < NDRV; i++) { + if_clone_detach(V_tuntap_driver_cloners[i]); + V_tuntap_driver_cloners[i] = NULL; + } + CURVNET_RESTORE(); + } +#endif + return (0); +} + +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); + } + osd_method_t methods[PR_MAXMETHOD] = { + [PR_METHOD_REMOVE] = tuntap_prison_remove, + }; + tuntap_osd_jail_slot = osd_jail_register(NULL, methods); + 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(). */ + 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 | MAKEDEV_CHECKNAME; + 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) { + mtx_destroy(&tp->tun_mtx); + cv_destroy(&tp->tun_cv); + 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); + 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); + 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 */ + +static int +tap_transmit(struct ifnet *ifp, struct mbuf *m) +{ + int error; + + BPF_MTAP(ifp, m); + IFQ_HANDOFF(ifp, m, error); + return (error); +} + +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); + 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 | IFCAP_MEXTPG; + if ((tp->tun_flags & TUN_L2) != 0) + ifp->if_capabilities |= + IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6 | IFCAP_LRO; + ifp->if_capenable |= IFCAP_LINKSTATE | IFCAP_MEXTPG; + + if ((tp->tun_flags & TUN_L2) != 0) { + ifp->if_init = tunifinit; + ifp->if_start = tunstart_l2; + ifp->if_transmit = tap_transmit; + ifp->if_qflush = if_qflush; + + 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 __diagused, 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 defined(INET) || defined(INET6) + if (l2tun && tp->tun_lro_ready) { + TUNDEBUG (ifp, "LRO disabled\n"); + tcp_lro_free(&tp->tun_lro); + tp->tun_lro_ready = false; + } +#endif + 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); + 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); + if ((tp->tun_flags & TUN_TRANSIENT) != 0) { + struct if_clone *cloner; + int error __diagused; + + /* Mark it busy so that nothing can re-open it. */ + tp->tun_flags |= TUN_DYING; + TUN_UNLOCK(tp); + + CURVNET_SET_QUIET(ifp->if_home_vnet); + cloner = tuntap_cloner_from_flags(tp->tun_flags); + CURVNET_RESTORE(); + + error = if_clone_destroyif(cloner, ifp); + MPASS(error == 0 || error == EINTR || error == ERESTART); + return; + } + + 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 { +#if defined(INET) || defined(INET6) + if (tcp_lro_init(&tp->tun_lro) == 0) { + TUNDEBUG(ifp, "LRO enabled\n"); + tp->tun_lro.ifp = ifp; + tp->tun_lro_ready = true; + } else { + TUNDEBUG(ifp, "Could not enable LRO\n"); + tp->tun_lro_ready = false; + } +#endif + 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 | IFM_FDX | IFM_1000_T; + 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 || dst->sa_family == pseudo_AF_HDRCMPLT) + bcopy(dst->sa_data, &af, sizeof(af)); + else + af = RO_GET_FAMILY(ro, dst); + + BPF_MTAP2(ifp, &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 TUNSTRANSIENT: + TUN_LOCK(tp); + if (*(int *)data) + tp->tun_flags |= TUN_TRANSIENT; + else + tp->tun_flags &= ~TUN_TRANSIENT; + TUN_UNLOCK(tp); + break; + case TUNGTRANSIENT: + TUN_LOCK(tp); + *(int *)data = (tp->tun_flags & TUN_TRANSIENT) != 0; + TUN_UNLOCK(tp); + 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, + "tunread", 0); + if (error != 0) { + TUN_UNLOCK(tp); + return (error); + } + } + TUN_UNLOCK(tp); + + 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); + } + if (error == 0) + error = m_mbuftouio(uio, m, 0); + 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 ((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) { + if (virtio_net_rx_csum(m, &vhdr->hdr)) { + m_freem(m); + return (0); + } + } else { + switch (ntohs(eh->ether_type)) { +#ifdef INET + case ETHERTYPE_IP: + if (ifp->if_capenable & IFCAP_RXCSUM) { + m->m_pkthdr.csum_flags |= + CSUM_IP_CHECKED | CSUM_IP_VALID | + CSUM_DATA_VALID | CSUM_SCTP_VALID | + CSUM_PSEUDO_HDR; + m->m_pkthdr.csum_data = 0xffff; + } + break; +#endif +#ifdef INET6 + case ETHERTYPE_IPV6: + if (ifp->if_capenable & IFCAP_RXCSUM_IPV6) { + m->m_pkthdr.csum_flags |= + CSUM_DATA_VALID_IPV6 | CSUM_SCTP_VALID | + CSUM_PSEUDO_HDR; + m->m_pkthdr.csum_data = 0xffff; + } + break; +#endif + } + } + + /* Pass packet up to parent. */ + CURVNET_SET(ifp->if_vnet); + NET_EPOCH_ENTER(et); +#if defined(INET) || defined(INET6) + if (tp->tun_lro_ready && ifp->if_capenable & IFCAP_LRO && + tcp_lro_rx(&tp->tun_lro, m, 0) == 0) + tcp_lro_flush_all(&tp->tun_lro); + else +#endif + (*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); +} |