/* $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 * All rights reserved. * Copyright (c) 2019 Kyle Evans * * 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 * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET #include #endif #ifdef INET6 #include #include #endif #include #include #include #include #include #include #include #include #include #include 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 */ 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 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 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_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); } /* * 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); } 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) { dev_ref(dev); tuncreate(dev); struct tuntap_softc *tp = dev->si_drv1; *ifpp = tp->tun_ifp; } 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) { dev_ref(*dev); 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, uint32_t flags) { 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) { 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 vnet_tun_uninit(const void *unused __unused) { for (u_int i = 0; i < NDRV; ++i) if_clone_detach(V_tuntap_driver_cloners[i]); } 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); 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 | 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) { 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 */ static int tap_transmit(struct ifnet *ifp, struct mbuf *m) { int error; BPF_MTAP(ifp, m); IFQ_HANDOFF(ifp, m, error); return (error); } /* 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); 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; if ((tp->tun_flags & TUN_L2) != 0) ifp->if_capabilities |= IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6 | IFCAP_LRO; ifp->if_capenable |= IFCAP_LINKSTATE; 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 + 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 { #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 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); 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 ((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); }