if_tun.c revision 256381
1139749Simp/* $NetBSD: if_tun.c,v 1.14 1994/06/29 06:36:25 cgd Exp $ */ 2116491Sharti 3116491Sharti/*- 4116491Sharti * Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk> 5119418Sobrien * Nottingham University 1987. 6116491Sharti * 7116491Sharti * This source may be freely distributed, however I would be interested 8116491Sharti * in any changes that are made. 9116491Sharti * 10116491Sharti * This driver takes packets off the IP i/f and hands them up to a 11116491Sharti * user process to have its wicked way with. This driver has it's 12116491Sharti * roots in a similar driver written by Phil Cockcroft (formerly) at 13116491Sharti * UCL. This driver is based much more on read/write/poll mode of 14116491Sharti * operation though. 15116491Sharti * 16116491Sharti * $FreeBSD: stable/10/sys/net/if_tun.c 256381 2013-10-12 15:31:36Z markm $ 17116491Sharti */ 18116491Sharti 19116491Sharti#include "opt_atalk.h" 20116491Sharti#include "opt_inet.h" 21116491Sharti#include "opt_inet6.h" 22116491Sharti#include "opt_ipx.h" 23116491Sharti 24116491Sharti#include <sys/param.h> 25116491Sharti#include <sys/priv.h> 26116491Sharti#include <sys/proc.h> 27119418Sobrien#include <sys/systm.h> 28119418Sobrien#include <sys/jail.h> 29119418Sobrien#include <sys/mbuf.h> 30119418Sobrien#include <sys/module.h> 31119418Sobrien#include <sys/socket.h> 32119418Sobrien#include <sys/fcntl.h> 33116491Sharti#include <sys/filio.h> 34116491Sharti#include <sys/sockio.h> 35116491Sharti#include <sys/ttycom.h> 36116491Sharti#include <sys/poll.h> 37116491Sharti#include <sys/selinfo.h> 38116491Sharti#include <sys/signalvar.h> 39116491Sharti#include <sys/filedesc.h> 40116491Sharti#include <sys/kernel.h> 41116491Sharti#include <sys/sysctl.h> 42116491Sharti#include <sys/conf.h> 43116491Sharti#include <sys/uio.h> 44116491Sharti#include <sys/malloc.h> 45116491Sharti#include <sys/random.h> 46116491Sharti 47116491Sharti#include <net/if.h> 48116491Sharti#include <net/if_clone.h> 49116491Sharti#include <net/if_types.h> 50116491Sharti#include <net/netisr.h> 51116491Sharti#include <net/route.h> 52116491Sharti#include <net/vnet.h> 53116491Sharti#ifdef INET 54116491Sharti#include <netinet/in.h> 55116491Sharti#endif 56116491Sharti#include <net/bpf.h> 57116491Sharti#include <net/if_tun.h> 58116491Sharti 59116491Sharti#include <sys/queue.h> 60116491Sharti#include <sys/condvar.h> 61116491Sharti 62116491Sharti#include <security/mac/mac_framework.h> 63116491Sharti 64116491Sharti/* 65116491Sharti * tun_list is protected by global tunmtx. Other mutable fields are 66116491Sharti * protected by tun->tun_mtx, or by their owning subsystem. tun_dev is 67116491Sharti * static for the duration of a tunnel interface. 68116491Sharti */ 69116491Shartistruct tun_softc { 70116491Sharti TAILQ_ENTRY(tun_softc) tun_list; 71119280Simp struct cdev *tun_dev; 72119280Simp u_short tun_flags; /* misc flags */ 73116491Sharti#define TUN_OPEN 0x0001 74116491Sharti#define TUN_INITED 0x0002 75116491Sharti#define TUN_RCOLL 0x0004 76116491Sharti#define TUN_IASET 0x0008 77116491Sharti#define TUN_DSTADDR 0x0010 78116491Sharti#define TUN_LMODE 0x0020 79116491Sharti#define TUN_RWAIT 0x0040 80116491Sharti#define TUN_ASYNC 0x0080 81116491Sharti#define TUN_IFHEAD 0x0100 82116491Sharti 83116491Sharti#define TUN_READY (TUN_OPEN | TUN_INITED) 84116491Sharti 85116491Sharti /* 86121729Sharti * XXXRW: tun_pid is used to exclusively lock /dev/tun. Is this 87121729Sharti * actually needed? Can we just return EBUSY if already open? 88121729Sharti * Problem is that this involved inherent races when a tun device 89121675Sharti * is handed off from one process to another, as opposed to just 90121675Sharti * being slightly stale informationally. 91116491Sharti */ 92121675Sharti pid_t tun_pid; /* owning pid */ 93121675Sharti struct ifnet *tun_ifp; /* the interface */ 94121744Sharti struct sigio *tun_sigio; /* information for async I/O */ 95121744Sharti struct selinfo tun_rsel; /* read select */ 96121744Sharti struct mtx tun_mtx; /* protect mutable softc fields */ 97121744Sharti struct cv tun_cv; /* protect against ref'd dev destroy */ 98121744Sharti}; 99121744Sharti#define TUN2IFP(sc) ((sc)->tun_ifp) 100121744Sharti 101121744Sharti#define TUNDEBUG if (tundebug) if_printf 102121744Sharti 103121744Sharti/* 104121744Sharti * All mutable global variables in if_tun are locked using tunmtx, with 105121744Sharti * the exception of tundebug, which is used unlocked, and tunclones, 106121744Sharti * which is static after setup. 107121744Sharti */ 108121744Shartistatic struct mtx tunmtx; 109121744Shartistatic const char tunname[] = "tun"; 110121744Shartistatic MALLOC_DEFINE(M_TUN, tunname, "Tunnel Interface"); 111121744Shartistatic int tundebug = 0; 112121675Shartistatic int tundclone = 1; 113170411Smjacobstatic struct clonedevs *tunclones; 114121675Shartistatic TAILQ_HEAD(,tun_softc) tunhead = TAILQ_HEAD_INITIALIZER(tunhead); 115121675ShartiSYSCTL_INT(_debug, OID_AUTO, if_tun_debug, CTLFLAG_RW, &tundebug, 0, ""); 116121675Sharti 117121675ShartiSYSCTL_DECL(_net_link); 118148067Sjhbstatic SYSCTL_NODE(_net_link, OID_AUTO, tun, CTLFLAG_RW, 0, 119148067Sjhb "IP tunnel software network interface."); 120121675ShartiSYSCTL_INT(_net_link_tun, OID_AUTO, devfs_cloning, CTLFLAG_RW, &tundclone, 0, 121121675Sharti "Enable legacy devfs interface creation."); 122121675Sharti 123121675ShartiTUNABLE_INT("net.link.tun.devfs_cloning", &tundclone); 124121675Sharti 125121675Shartistatic void tunclone(void *arg, struct ucred *cred, char *name, 126121675Sharti int namelen, struct cdev **dev); 127121675Shartistatic void tuncreate(const char *name, struct cdev *dev); 128121675Shartistatic int tunifioctl(struct ifnet *, u_long, caddr_t); 129121675Shartistatic void tuninit(struct ifnet *); 130121675Shartistatic int tunmodevent(module_t, int, void *); 131121675Shartistatic int tunoutput(struct ifnet *, struct mbuf *, 132148067Sjhb const struct sockaddr *, struct route *ro); 133148067Sjhbstatic void tunstart(struct ifnet *); 134121675Sharti 135121675Shartistatic int tun_clone_create(struct if_clone *, int, caddr_t); 136121675Shartistatic void tun_clone_destroy(struct ifnet *); 137121675Shartistatic struct if_clone *tun_cloner; 138121675Sharti 139121675Shartistatic d_open_t tunopen; 140121675Shartistatic d_close_t tunclose; 141148067Sjhbstatic d_read_t tunread; 142148067Sjhbstatic d_write_t tunwrite; 143121675Shartistatic d_ioctl_t tunioctl; 144121675Shartistatic d_poll_t tunpoll; 145121675Shartistatic d_kqfilter_t tunkqfilter; 146121675Sharti 147121675Shartistatic int tunkqread(struct knote *, long); 148121675Shartistatic int tunkqwrite(struct knote *, long); 149121675Shartistatic void tunkqdetach(struct knote *); 150116491Sharti 151116491Shartistatic struct filterops tun_read_filterops = { 152116491Sharti .f_isfd = 1, 153116491Sharti .f_attach = NULL, 154116491Sharti .f_detach = tunkqdetach, 155116491Sharti .f_event = tunkqread, 156116491Sharti}; 157116491Sharti 158116491Shartistatic struct filterops tun_write_filterops = { 159116491Sharti .f_isfd = 1, 160116491Sharti .f_attach = NULL, 161116491Sharti .f_detach = tunkqdetach, 162116491Sharti .f_event = tunkqwrite, 163116491Sharti}; 164116491Sharti 165116491Shartistatic struct cdevsw tun_cdevsw = { 166116491Sharti .d_version = D_VERSION, 167116491Sharti .d_flags = D_NEEDMINOR, 168116491Sharti .d_open = tunopen, 169116491Sharti .d_close = tunclose, 170116491Sharti .d_read = tunread, 171116491Sharti .d_write = tunwrite, 172116491Sharti .d_ioctl = tunioctl, 173116491Sharti .d_poll = tunpoll, 174116491Sharti .d_kqfilter = tunkqfilter, 175116491Sharti .d_name = tunname, 176116491Sharti}; 177116491Sharti 178116491Shartistatic int 179116491Shartitun_clone_create(struct if_clone *ifc, int unit, caddr_t params) 180116491Sharti{ 181116491Sharti struct cdev *dev; 182116491Sharti int i; 183116491Sharti 184116491Sharti /* find any existing device, or allocate new unit number */ 185116491Sharti i = clone_create(&tunclones, &tun_cdevsw, &unit, &dev, 0); 186116491Sharti if (i) { 187116491Sharti /* No preexisting struct cdev *, create one */ 188116491Sharti dev = make_dev(&tun_cdevsw, unit, 189116491Sharti UID_UUCP, GID_DIALER, 0600, "%s%d", tunname, unit); 190116491Sharti } 191116491Sharti tuncreate(tunname, dev); 192116491Sharti 193116491Sharti return (0); 194116491Sharti} 195116491Sharti 196116491Shartistatic void 197116491Shartitunclone(void *arg, struct ucred *cred, char *name, int namelen, 198116491Sharti struct cdev **dev) 199116491Sharti{ 200116491Sharti char devname[SPECNAMELEN + 1]; 201116491Sharti int u, i, append_unit; 202121686Sharti 203116491Sharti if (*dev != NULL) 204116491Sharti return; 205116491Sharti 206116491Sharti /* 207116491Sharti * If tun cloning is enabled, only the superuser can create an 208116491Sharti * interface. 209147256Sbrooks */ 210116491Sharti if (!tundclone || priv_check_cred(cred, PRIV_NET_IFCREATE, 0) != 0) 211116491Sharti return; 212116491Sharti 213116491Sharti if (strcmp(name, tunname) == 0) { 214116491Sharti u = -1; 215117382Sharti } else if (dev_stdclone(name, NULL, tunname, &u) != 1) 216116491Sharti return; /* Don't recognise the name */ 217147256Sbrooks if (u != -1 && u > IF_MAXUNIT) 218116491Sharti return; /* Unit number too high */ 219116491Sharti 220116491Sharti if (u == -1) 221116491Sharti append_unit = 1; 222116491Sharti else 223116491Sharti append_unit = 0; 224116491Sharti 225116491Sharti CURVNET_SET(CRED_TO_VNET(cred)); 226116491Sharti /* find any existing device, or allocate new unit number */ 227116491Sharti i = clone_create(&tunclones, &tun_cdevsw, &u, dev, 0); 228116491Sharti if (i) { 229121729Sharti if (append_unit) { 230116491Sharti namelen = snprintf(devname, sizeof(devname), "%s%d", 231116491Sharti name, u); 232116491Sharti name = devname; 233116491Sharti } 234116491Sharti /* No preexisting struct cdev *, create one */ 235116491Sharti *dev = make_dev_credf(MAKEDEV_REF, &tun_cdevsw, u, cred, 236116491Sharti UID_UUCP, GID_DIALER, 0600, "%s", name); 237122111Sharti } 238121675Sharti 239121675Sharti if_clone_create(name, namelen, NULL); 240116491Sharti CURVNET_RESTORE(); 241116491Sharti} 242116491Sharti 243116491Shartistatic void 244121729Shartitun_destroy(struct tun_softc *tp) 245116491Sharti{ 246116491Sharti struct cdev *dev; 247116491Sharti 248116491Sharti mtx_lock(&tp->tun_mtx); 249116491Sharti if ((tp->tun_flags & TUN_OPEN) != 0) 250116491Sharti cv_wait_unlock(&tp->tun_cv, &tp->tun_mtx); 251116491Sharti else 252122111Sharti mtx_unlock(&tp->tun_mtx); 253121675Sharti 254121675Sharti CURVNET_SET(TUN2IFP(tp)->if_vnet); 255116491Sharti dev = tp->tun_dev; 256116491Sharti bpfdetach(TUN2IFP(tp)); 257116491Sharti if_detach(TUN2IFP(tp)); 258116491Sharti if_free(TUN2IFP(tp)); 259116491Sharti destroy_dev(dev); 260116491Sharti seldrain(&tp->tun_rsel); 261116491Sharti knlist_clear(&tp->tun_rsel.si_note, 0); 262116491Sharti knlist_destroy(&tp->tun_rsel.si_note); 263254842Sandre mtx_destroy(&tp->tun_mtx); 264254799Sandre cv_destroy(&tp->tun_cv); 265116491Sharti free(tp, M_TUN); 266116491Sharti CURVNET_RESTORE(); 267116491Sharti} 268116491Sharti 269121729Shartistatic void 270121729Shartitun_clone_destroy(struct ifnet *ifp) 271121729Sharti{ 272121675Sharti struct tun_softc *tp = ifp->if_softc; 273254842Sandre 274116491Sharti mtx_lock(&tunmtx); 275254842Sandre TAILQ_REMOVE(&tunhead, tp, tun_list); 276254799Sandre mtx_unlock(&tunmtx); 277116491Sharti tun_destroy(tp); 278116491Sharti} 279116491Sharti 280116491Shartistatic int 281121729Shartitunmodevent(module_t mod, int type, void *data) 282121729Sharti{ 283121729Sharti static eventhandler_tag tag; 284121675Sharti struct tun_softc *tp; 285254842Sandre 286116491Sharti switch (type) { 287116491Sharti case MOD_LOAD: 288116491Sharti mtx_init(&tunmtx, "tunmtx", NULL, MTX_DEF); 289116491Sharti clone_setup(&tunclones); 290116491Sharti tag = EVENTHANDLER_REGISTER(dev_clone, tunclone, 0, 1000); 291116491Sharti if (tag == NULL) 292116491Sharti return (ENOMEM); 293116491Sharti tun_cloner = if_clone_simple(tunname, tun_clone_create, 294116491Sharti tun_clone_destroy, 0); 295116491Sharti break; 296116491Sharti case MOD_UNLOAD: 297116491Sharti if_clone_detach(tun_cloner); 298116491Sharti EVENTHANDLER_DEREGISTER(dev_clone, tag); 299116491Sharti drain_dev_clone_events(); 300116491Sharti 301116491Sharti mtx_lock(&tunmtx); 302116491Sharti while ((tp = TAILQ_FIRST(&tunhead)) != NULL) { 303116491Sharti TAILQ_REMOVE(&tunhead, tp, tun_list); 304116491Sharti mtx_unlock(&tunmtx); 305116491Sharti tun_destroy(tp); 306116491Sharti mtx_lock(&tunmtx); 307116491Sharti } 308116491Sharti mtx_unlock(&tunmtx); 309116491Sharti clone_cleanup(&tunclones); 310116491Sharti mtx_destroy(&tunmtx); 311116491Sharti break; 312121617Sharti default: 313116491Sharti return EOPNOTSUPP; 314116491Sharti } 315121680Sharti return 0; 316121680Sharti} 317121680Sharti 318121680Shartistatic moduledata_t tun_mod = { 319116491Sharti "if_tun", 320116491Sharti tunmodevent, 321116491Sharti 0 322116491Sharti}; 323116491Sharti 324116491ShartiDECLARE_MODULE(if_tun, tun_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 325116491ShartiMODULE_VERSION(if_tun, 1); 326116491Sharti 327116491Shartistatic void 328116491Shartitunstart(struct ifnet *ifp) 329116491Sharti{ 330116491Sharti struct tun_softc *tp = ifp->if_softc; 331121680Sharti struct mbuf *m; 332116491Sharti 333116491Sharti TUNDEBUG(ifp,"%s starting\n", ifp->if_xname); 334121676Sharti if (ALTQ_IS_ENABLED(&ifp->if_snd)) { 335243857Sglebius IFQ_LOCK(&ifp->if_snd); 336116491Sharti IFQ_POLL_NOLOCK(&ifp->if_snd, m); 337147256Sbrooks if (m == NULL) { 338116491Sharti IFQ_UNLOCK(&ifp->if_snd); 339116491Sharti return; 340116491Sharti } 341116491Sharti IFQ_UNLOCK(&ifp->if_snd); 342116491Sharti } 343116491Sharti 344116491Sharti mtx_lock(&tp->tun_mtx); 345116491Sharti if (tp->tun_flags & TUN_RWAIT) { 346116491Sharti tp->tun_flags &= ~TUN_RWAIT; 347116491Sharti wakeup(tp); 348116491Sharti } 349116491Sharti selwakeuppri(&tp->tun_rsel, PZERO + 1); 350123810Salfred KNOTE_LOCKED(&tp->tun_rsel.si_note, 0); 351116491Sharti if (tp->tun_flags & TUN_ASYNC && tp->tun_sigio) { 352116491Sharti mtx_unlock(&tp->tun_mtx); 353116491Sharti pgsigio(&tp->tun_sigio, SIGIO, 0); 354116491Sharti } else 355116491Sharti mtx_unlock(&tp->tun_mtx); 356116491Sharti} 357121680Sharti 358121680Sharti/* XXX: should return an error code so it can fail. */ 359116491Shartistatic void 360116491Shartituncreate(const char *name, struct cdev *dev) 361116491Sharti{ 362116491Sharti struct tun_softc *sc; 363121680Sharti struct ifnet *ifp; 364121680Sharti 365121680Sharti sc = malloc(sizeof(*sc), M_TUN, M_WAITOK | M_ZERO); 366121680Sharti mtx_init(&sc->tun_mtx, "tun_mtx", NULL, MTX_DEF); 367121680Sharti cv_init(&sc->tun_cv, "tun_condvar"); 368116491Sharti sc->tun_flags = TUN_INITED; 369121680Sharti sc->tun_dev = dev; 370121680Sharti mtx_lock(&tunmtx); 371121729Sharti TAILQ_INSERT_TAIL(&tunhead, sc, tun_list); 372121680Sharti mtx_unlock(&tunmtx); 373121680Sharti 374121680Sharti ifp = sc->tun_ifp = if_alloc(IFT_PPP); 375121680Sharti if (ifp == NULL) 376121680Sharti panic("%s%d: failed to if_alloc() interface.\n", 377121680Sharti name, dev2unit(dev)); 378121680Sharti if_initname(ifp, name, dev2unit(dev)); 379121680Sharti ifp->if_mtu = TUNMTU; 380121680Sharti ifp->if_ioctl = tunifioctl; 381121680Sharti ifp->if_output = tunoutput; 382121680Sharti ifp->if_start = tunstart; 383121680Sharti ifp->if_flags = IFF_POINTOPOINT | IFF_MULTICAST; 384121680Sharti ifp->if_softc = sc; 385121680Sharti IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen); 386121680Sharti ifp->if_snd.ifq_drv_maxlen = 0; 387121680Sharti IFQ_SET_READY(&ifp->if_snd); 388121680Sharti knlist_init_mtx(&sc->tun_rsel.si_note, &sc->tun_mtx); 389121729Sharti ifp->if_capabilities |= IFCAP_LINKSTATE; 390121680Sharti ifp->if_capenable |= IFCAP_LINKSTATE; 391121680Sharti 392121680Sharti if_attach(ifp); 393121680Sharti bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 394121680Sharti dev->si_drv1 = sc; 395121680Sharti TUNDEBUG(ifp, "interface %s is created, minor = %#x\n", 396121680Sharti ifp->if_xname, dev2unit(dev)); 397121680Sharti} 398121680Sharti 399121680Shartistatic int 400121680Shartitunopen(struct cdev *dev, int flag, int mode, struct thread *td) 401121680Sharti{ 402121680Sharti struct ifnet *ifp; 403116491Sharti struct tun_softc *tp; 404116491Sharti 405116491Sharti /* 406116491Sharti * XXXRW: Non-atomic test and set of dev->si_drv1 requires 407116491Sharti * synchronization. 408121617Sharti */ 409121617Sharti tp = dev->si_drv1; 410116491Sharti if (!tp) { 411116491Sharti tuncreate(tunname, dev); 412116491Sharti tp = dev->si_drv1; 413116491Sharti } 414116491Sharti 415116491Sharti /* 416116491Sharti * XXXRW: This use of tun_pid is subject to error due to the 417116491Sharti * fact that a reference to the tunnel can live beyond the 418116491Sharti * death of the process that created it. Can we replace this 419116491Sharti * with a simple busy flag? 420116491Sharti */ 421116491Sharti mtx_lock(&tp->tun_mtx); 422116491Sharti if (tp->tun_pid != 0 && tp->tun_pid != td->td_proc->p_pid) { 423116491Sharti mtx_unlock(&tp->tun_mtx); 424121680Sharti return (EBUSY); 425116491Sharti } 426116491Sharti tp->tun_pid = td->td_proc->p_pid; 427116491Sharti 428116491Sharti tp->tun_flags |= TUN_OPEN; 429116491Sharti ifp = TUN2IFP(tp); 430116491Sharti if_link_state_change(ifp, LINK_STATE_UP); 431116491Sharti TUNDEBUG(ifp, "open\n"); 432116491Sharti mtx_unlock(&tp->tun_mtx); 433116491Sharti 434116491Sharti return (0); 435116491Sharti} 436116491Sharti 437116491Sharti/* 438116491Sharti * tunclose - close the device - mark i/f down & delete 439116491Sharti * routing info 440116491Sharti */ 441116491Shartistatic int 442243857Sglebiustunclose(struct cdev *dev, int foo, int bar, struct thread *td) 443121676Sharti{ 444116491Sharti struct tun_softc *tp; 445116491Sharti struct ifnet *ifp; 446116491Sharti 447116491Sharti tp = dev->si_drv1; 448116491Sharti ifp = TUN2IFP(tp); 449116491Sharti 450116491Sharti mtx_lock(&tp->tun_mtx); 451116491Sharti tp->tun_flags &= ~TUN_OPEN; 452121729Sharti tp->tun_pid = 0; 453121729Sharti 454121729Sharti /* 455121729Sharti * junk all pending output 456116491Sharti */ 457121729Sharti CURVNET_SET(ifp->if_vnet); 458121729Sharti IFQ_PURGE(&ifp->if_snd); 459121729Sharti 460121676Sharti if (ifp->if_flags & IFF_UP) { 461121677Sharti mtx_unlock(&tp->tun_mtx); 462150347Sandre if_down(ifp); 463175872Sphk mtx_lock(&tp->tun_mtx); 464121676Sharti } 465121676Sharti 466254842Sandre /* Delete all addresses and routes which reference this interface. */ 467116491Sharti if (ifp->if_drv_flags & IFF_DRV_RUNNING) { 468116491Sharti struct ifaddr *ifa; 469116491Sharti 470116491Sharti ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 471116491Sharti mtx_unlock(&tp->tun_mtx); 472116491Sharti TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 473116491Sharti /* deal w/IPv4 PtP destination; unlocked read */ 474116491Sharti if (ifa->ifa_addr->sa_family == AF_INET) { 475116491Sharti rtinit(ifa, (int)RTM_DELETE, 476121729Sharti tp->tun_flags & TUN_DSTADDR ? RTF_HOST : 0); 477121729Sharti } else { 478121729Sharti rtinit(ifa, (int)RTM_DELETE, 0); 479121729Sharti } 480116491Sharti } 481121729Sharti if_purgeaddrs(ifp); 482121729Sharti mtx_lock(&tp->tun_mtx); 483121729Sharti } 484121676Sharti if_link_state_change(ifp, LINK_STATE_DOWN); 485121677Sharti CURVNET_RESTORE(); 486150347Sandre 487175872Sphk funsetown(&tp->tun_sigio); 488121676Sharti selwakeuppri(&tp->tun_rsel, PZERO + 1); 489121676Sharti KNOTE_LOCKED(&tp->tun_rsel.si_note, 0); 490254842Sandre TUNDEBUG (ifp, "closed\n"); 491116491Sharti 492116491Sharti cv_broadcast(&tp->tun_cv); 493116491Sharti mtx_unlock(&tp->tun_mtx); 494116491Sharti return (0); 495116491Sharti} 496116491Sharti 497116491Shartistatic void 498116491Shartituninit(struct ifnet *ifp) 499116491Sharti{ 500116491Sharti struct tun_softc *tp = ifp->if_softc; 501116491Sharti#ifdef INET 502116491Sharti struct ifaddr *ifa; 503116491Sharti#endif 504116491Sharti 505116491Sharti TUNDEBUG(ifp, "tuninit\n"); 506116491Sharti 507116491Sharti mtx_lock(&tp->tun_mtx); 508116491Sharti ifp->if_flags |= IFF_UP; 509116491Sharti ifp->if_drv_flags |= IFF_DRV_RUNNING; 510116491Sharti getmicrotime(&ifp->if_lastchange); 511116491Sharti 512116491Sharti#ifdef INET 513116491Sharti if_addr_rlock(ifp); 514116491Sharti TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 515116491Sharti if (ifa->ifa_addr->sa_family == AF_INET) { 516116491Sharti struct sockaddr_in *si; 517121680Sharti 518116491Sharti si = (struct sockaddr_in *)ifa->ifa_addr; 519116491Sharti if (si->sin_addr.s_addr) 520116491Sharti tp->tun_flags |= TUN_IASET; 521116491Sharti 522116491Sharti si = (struct sockaddr_in *)ifa->ifa_dstaddr; 523116491Sharti if (si && si->sin_addr.s_addr) 524116491Sharti tp->tun_flags |= TUN_DSTADDR; 525116491Sharti } 526116491Sharti } 527116491Sharti if_addr_runlock(ifp); 528116491Sharti#endif 529116491Sharti mtx_unlock(&tp->tun_mtx); 530116491Sharti} 531116491Sharti 532116491Sharti/* 533116491Sharti * Process an ioctl request. 534116491Sharti */ 535116491Shartistatic int 536116491Shartitunifioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 537116491Sharti{ 538116491Sharti struct ifreq *ifr = (struct ifreq *)data; 539116491Sharti struct tun_softc *tp = ifp->if_softc; 540116491Sharti struct ifstat *ifs; 541116491Sharti int error = 0; 542148887Srwatson 543116491Sharti switch(cmd) { 544116491Sharti case SIOCGIFSTATUS: 545116491Sharti ifs = (struct ifstat *)data; 546116491Sharti mtx_lock(&tp->tun_mtx); 547116491Sharti if (tp->tun_pid) 548116491Sharti sprintf(ifs->ascii + strlen(ifs->ascii), 549116491Sharti "\tOpened by PID %d\n", tp->tun_pid); 550116491Sharti mtx_unlock(&tp->tun_mtx); 551116491Sharti break; 552116491Sharti case SIOCSIFADDR: 553116491Sharti tuninit(ifp); 554116491Sharti TUNDEBUG(ifp, "address set\n"); 555116491Sharti break; 556116491Sharti case SIOCSIFMTU: 557116491Sharti ifp->if_mtu = ifr->ifr_mtu; 558116491Sharti TUNDEBUG(ifp, "mtu set\n"); 559116491Sharti break; 560116491Sharti case SIOCSIFFLAGS: 561116491Sharti case SIOCADDMULTI: 562116491Sharti case SIOCDELMULTI: 563116491Sharti break; 564116491Sharti default: 565116491Sharti error = EINVAL; 566116491Sharti } 567116491Sharti return (error); 568116491Sharti} 569116491Sharti 570116491Sharti/* 571116491Sharti * tunoutput - queue packets from higher level ready to put out. 572116491Sharti */ 573116491Shartistatic int 574116491Shartitunoutput(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst, 575116491Sharti struct route *ro) 576116491Sharti{ 577116491Sharti struct tun_softc *tp = ifp->if_softc; 578116491Sharti u_short cached_tun_flags; 579116491Sharti int error; 580116491Sharti u_int32_t af; 581116491Sharti 582116491Sharti TUNDEBUG (ifp, "tunoutput\n"); 583116491Sharti 584116491Sharti#ifdef MAC 585116491Sharti error = mac_ifnet_check_transmit(ifp, m0); 586116491Sharti if (error) { 587116491Sharti m_freem(m0); 588116491Sharti return (error); 589116491Sharti } 590116491Sharti#endif 591116491Sharti 592116491Sharti /* Could be unlocked read? */ 593116491Sharti mtx_lock(&tp->tun_mtx); 594116491Sharti cached_tun_flags = tp->tun_flags; 595116491Sharti mtx_unlock(&tp->tun_mtx); 596116491Sharti if ((cached_tun_flags & TUN_READY) != TUN_READY) { 597116491Sharti TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags); 598147256Sbrooks m_freem (m0); 599116491Sharti return (EHOSTDOWN); 600116491Sharti } 601116491Sharti 602116491Sharti if ((ifp->if_flags & IFF_UP) != IFF_UP) { 603116491Sharti m_freem (m0); 604116491Sharti return (EHOSTDOWN); 605116491Sharti } 606116491Sharti 607116491Sharti /* BPF writes need to be handled specially. */ 608116491Sharti if (dst->sa_family == AF_UNSPEC) 609116491Sharti bcopy(dst->sa_data, &af, sizeof(af)); 610116491Sharti else 611116491Sharti af = dst->sa_family; 612116491Sharti 613147256Sbrooks if (bpf_peers_present(ifp->if_bpf)) 614116491Sharti bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m0); 615116491Sharti 616116491Sharti /* prepend sockaddr? this may abort if the mbuf allocation fails */ 617116491Sharti if (cached_tun_flags & TUN_LMODE) { 618116491Sharti /* allocate space for sockaddr */ 619116491Sharti M_PREPEND(m0, dst->sa_len, M_NOWAIT); 620116491Sharti 621116491Sharti /* if allocation failed drop packet */ 622116491Sharti if (m0 == NULL) { 623116491Sharti ifp->if_iqdrops++; 624116491Sharti ifp->if_oerrors++; 625116491Sharti return (ENOBUFS); 626116491Sharti } else { 627116491Sharti bcopy(dst, m0->m_data, dst->sa_len); 628116491Sharti } 629116491Sharti } 630116491Sharti 631116491Sharti if (cached_tun_flags & TUN_IFHEAD) { 632116491Sharti /* Prepend the address family */ 633116491Sharti M_PREPEND(m0, 4, M_NOWAIT); 634116491Sharti 635116491Sharti /* if allocation failed drop packet */ 636147256Sbrooks if (m0 == NULL) { 637116491Sharti ifp->if_iqdrops++; 638116491Sharti ifp->if_oerrors++; 639116491Sharti return (ENOBUFS); 640116491Sharti } else 641116491Sharti *(u_int32_t *)m0->m_data = htonl(af); 642116491Sharti } else { 643116491Sharti#ifdef INET 644116491Sharti if (af != AF_INET) 645116491Sharti#endif 646116491Sharti { 647116491Sharti m_freem(m0); 648116491Sharti return (EAFNOSUPPORT); 649116491Sharti } 650116491Sharti } 651116491Sharti 652116491Sharti error = (ifp->if_transmit)(ifp, m0); 653116491Sharti if (error) 654116491Sharti return (ENOBUFS); 655116491Sharti ifp->if_opackets++; 656116491Sharti return (0); 657116491Sharti} 658116491Sharti 659147256Sbrooks/* 660116491Sharti * the cdevsw interface is now pretty minimal. 661116491Sharti */ 662116491Shartistatic int 663116491Shartitunioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, 664116491Sharti struct thread *td) 665116491Sharti{ 666116491Sharti int error; 667116491Sharti struct tun_softc *tp = dev->si_drv1; 668116491Sharti struct tuninfo *tunp; 669116491Sharti 670116491Sharti switch (cmd) { 671116491Sharti case TUNSIFINFO: 672116491Sharti tunp = (struct tuninfo *)data; 673147256Sbrooks if (tunp->mtu < IF_MINMTU) 674116491Sharti return (EINVAL); 675116491Sharti if (TUN2IFP(tp)->if_mtu != tunp->mtu) { 676116491Sharti error = priv_check(td, PRIV_NET_SETIFMTU); 677116491Sharti if (error) 678116491Sharti return (error); 679116491Sharti } 680116491Sharti mtx_lock(&tp->tun_mtx); 681116491Sharti TUN2IFP(tp)->if_mtu = tunp->mtu; 682147256Sbrooks TUN2IFP(tp)->if_type = tunp->type; 683116491Sharti TUN2IFP(tp)->if_baudrate = tunp->baudrate; 684116491Sharti mtx_unlock(&tp->tun_mtx); 685116491Sharti break; 686147256Sbrooks case TUNGIFINFO: 687116491Sharti tunp = (struct tuninfo *)data; 688116491Sharti mtx_lock(&tp->tun_mtx); 689116491Sharti tunp->mtu = TUN2IFP(tp)->if_mtu; 690116491Sharti tunp->type = TUN2IFP(tp)->if_type; 691116491Sharti tunp->baudrate = TUN2IFP(tp)->if_baudrate; 692147256Sbrooks mtx_unlock(&tp->tun_mtx); 693116491Sharti break; 694116491Sharti case TUNSDEBUG: 695116491Sharti tundebug = *(int *)data; 696116491Sharti break; 697116491Sharti case TUNGDEBUG: 698116491Sharti *(int *)data = tundebug; 699116491Sharti break; 700116491Sharti case TUNSLMODE: 701116491Sharti mtx_lock(&tp->tun_mtx); 702116491Sharti if (*(int *)data) { 703116491Sharti tp->tun_flags |= TUN_LMODE; 704116491Sharti tp->tun_flags &= ~TUN_IFHEAD; 705116491Sharti } else 706116491Sharti tp->tun_flags &= ~TUN_LMODE; 707116491Sharti mtx_unlock(&tp->tun_mtx); 708116491Sharti break; 709116491Sharti case TUNSIFHEAD: 710116491Sharti mtx_lock(&tp->tun_mtx); 711116491Sharti if (*(int *)data) { 712116491Sharti tp->tun_flags |= TUN_IFHEAD; 713116491Sharti tp->tun_flags &= ~TUN_LMODE; 714147256Sbrooks } else 715116491Sharti tp->tun_flags &= ~TUN_IFHEAD; 716116491Sharti mtx_unlock(&tp->tun_mtx); 717116491Sharti break; 718116491Sharti case TUNGIFHEAD: 719116491Sharti mtx_lock(&tp->tun_mtx); 720116491Sharti *(int *)data = (tp->tun_flags & TUN_IFHEAD) ? 1 : 0; 721116491Sharti mtx_unlock(&tp->tun_mtx); 722116491Sharti break; 723116491Sharti case TUNSIFMODE: 724116491Sharti /* deny this if UP */ 725116491Sharti if (TUN2IFP(tp)->if_flags & IFF_UP) 726116491Sharti return(EBUSY); 727116491Sharti 728116491Sharti switch (*(int *)data & ~IFF_MULTICAST) { 729116491Sharti case IFF_POINTOPOINT: 730116491Sharti case IFF_BROADCAST: 731116491Sharti mtx_lock(&tp->tun_mtx); 732116491Sharti TUN2IFP(tp)->if_flags &= 733 ~(IFF_BROADCAST|IFF_POINTOPOINT|IFF_MULTICAST); 734 TUN2IFP(tp)->if_flags |= *(int *)data; 735 mtx_unlock(&tp->tun_mtx); 736 break; 737 default: 738 return(EINVAL); 739 } 740 break; 741 case TUNSIFPID: 742 mtx_lock(&tp->tun_mtx); 743 tp->tun_pid = curthread->td_proc->p_pid; 744 mtx_unlock(&tp->tun_mtx); 745 break; 746 case FIONBIO: 747 break; 748 case FIOASYNC: 749 mtx_lock(&tp->tun_mtx); 750 if (*(int *)data) 751 tp->tun_flags |= TUN_ASYNC; 752 else 753 tp->tun_flags &= ~TUN_ASYNC; 754 mtx_unlock(&tp->tun_mtx); 755 break; 756 case FIONREAD: 757 if (!IFQ_IS_EMPTY(&TUN2IFP(tp)->if_snd)) { 758 struct mbuf *mb; 759 IFQ_LOCK(&TUN2IFP(tp)->if_snd); 760 IFQ_POLL_NOLOCK(&TUN2IFP(tp)->if_snd, mb); 761 for (*(int *)data = 0; mb != NULL; mb = mb->m_next) 762 *(int *)data += mb->m_len; 763 IFQ_UNLOCK(&TUN2IFP(tp)->if_snd); 764 } else 765 *(int *)data = 0; 766 break; 767 case FIOSETOWN: 768 return (fsetown(*(int *)data, &tp->tun_sigio)); 769 770 case FIOGETOWN: 771 *(int *)data = fgetown(&tp->tun_sigio); 772 return (0); 773 774 /* This is deprecated, FIOSETOWN should be used instead. */ 775 case TIOCSPGRP: 776 return (fsetown(-(*(int *)data), &tp->tun_sigio)); 777 778 /* This is deprecated, FIOGETOWN should be used instead. */ 779 case TIOCGPGRP: 780 *(int *)data = -fgetown(&tp->tun_sigio); 781 return (0); 782 783 default: 784 return (ENOTTY); 785 } 786 return (0); 787} 788 789/* 790 * The cdevsw read interface - reads a packet at a time, or at 791 * least as much of a packet as can be read. 792 */ 793static int 794tunread(struct cdev *dev, struct uio *uio, int flag) 795{ 796 struct tun_softc *tp = dev->si_drv1; 797 struct ifnet *ifp = TUN2IFP(tp); 798 struct mbuf *m; 799 int error=0, len; 800 801 TUNDEBUG (ifp, "read\n"); 802 mtx_lock(&tp->tun_mtx); 803 if ((tp->tun_flags & TUN_READY) != TUN_READY) { 804 mtx_unlock(&tp->tun_mtx); 805 TUNDEBUG (ifp, "not ready 0%o\n", tp->tun_flags); 806 return (EHOSTDOWN); 807 } 808 809 tp->tun_flags &= ~TUN_RWAIT; 810 811 do { 812 IFQ_DEQUEUE(&ifp->if_snd, m); 813 if (m == NULL) { 814 if (flag & O_NONBLOCK) { 815 mtx_unlock(&tp->tun_mtx); 816 return (EWOULDBLOCK); 817 } 818 tp->tun_flags |= TUN_RWAIT; 819 error = mtx_sleep(tp, &tp->tun_mtx, PCATCH | (PZERO + 1), 820 "tunread", 0); 821 if (error != 0) { 822 mtx_unlock(&tp->tun_mtx); 823 return (error); 824 } 825 } 826 } while (m == NULL); 827 mtx_unlock(&tp->tun_mtx); 828 829 while (m && uio->uio_resid > 0 && error == 0) { 830 len = min(uio->uio_resid, m->m_len); 831 if (len != 0) 832 error = uiomove(mtod(m, void *), len, uio); 833 m = m_free(m); 834 } 835 836 if (m) { 837 TUNDEBUG(ifp, "Dropping mbuf\n"); 838 m_freem(m); 839 } 840 return (error); 841} 842 843/* 844 * the cdevsw write interface - an atomic write is a packet - or else! 845 */ 846static int 847tunwrite(struct cdev *dev, struct uio *uio, int flag) 848{ 849 struct tun_softc *tp = dev->si_drv1; 850 struct ifnet *ifp = TUN2IFP(tp); 851 struct mbuf *m; 852 uint32_t family; 853 int isr; 854 855 TUNDEBUG(ifp, "tunwrite\n"); 856 857 if ((ifp->if_flags & IFF_UP) != IFF_UP) 858 /* ignore silently */ 859 return (0); 860 861 if (uio->uio_resid == 0) 862 return (0); 863 864 if (uio->uio_resid < 0 || uio->uio_resid > TUNMRU) { 865 TUNDEBUG(ifp, "len=%zd!\n", uio->uio_resid); 866 return (EIO); 867 } 868 869 if ((m = m_uiotombuf(uio, M_NOWAIT, 0, 0, M_PKTHDR)) == NULL) { 870 ifp->if_ierrors++; 871 return (ENOBUFS); 872 } 873 874 m->m_pkthdr.rcvif = ifp; 875#ifdef MAC 876 mac_ifnet_create_mbuf(ifp, m); 877#endif 878 879 /* Could be unlocked read? */ 880 mtx_lock(&tp->tun_mtx); 881 if (tp->tun_flags & TUN_IFHEAD) { 882 mtx_unlock(&tp->tun_mtx); 883 if (m->m_len < sizeof(family) && 884 (m = m_pullup(m, sizeof(family))) == NULL) 885 return (ENOBUFS); 886 family = ntohl(*mtod(m, u_int32_t *)); 887 m_adj(m, sizeof(family)); 888 } else { 889 mtx_unlock(&tp->tun_mtx); 890 family = AF_INET; 891 } 892 893 BPF_MTAP2(ifp, &family, sizeof(family), m); 894 895 switch (family) { 896#ifdef INET 897 case AF_INET: 898 isr = NETISR_IP; 899 break; 900#endif 901#ifdef INET6 902 case AF_INET6: 903 isr = NETISR_IPV6; 904 break; 905#endif 906#ifdef IPX 907 case AF_IPX: 908 isr = NETISR_IPX; 909 break; 910#endif 911#ifdef NETATALK 912 case AF_APPLETALK: 913 isr = NETISR_ATALK2; 914 break; 915#endif 916 default: 917 m_freem(m); 918 return (EAFNOSUPPORT); 919 } 920 if (harvest.point_to_point) 921 random_harvest(&(m->m_data), 12, 2, RANDOM_NET_TUN); 922 ifp->if_ibytes += m->m_pkthdr.len; 923 ifp->if_ipackets++; 924 CURVNET_SET(ifp->if_vnet); 925 M_SETFIB(m, ifp->if_fib); 926 netisr_dispatch(isr, m); 927 CURVNET_RESTORE(); 928 return (0); 929} 930 931/* 932 * tunpoll - the poll interface, this is only useful on reads 933 * really. The write detect always returns true, write never blocks 934 * anyway, it either accepts the packet or drops it. 935 */ 936static int 937tunpoll(struct cdev *dev, int events, struct thread *td) 938{ 939 struct tun_softc *tp = dev->si_drv1; 940 struct ifnet *ifp = TUN2IFP(tp); 941 int revents = 0; 942 struct mbuf *m; 943 944 TUNDEBUG(ifp, "tunpoll\n"); 945 946 if (events & (POLLIN | POLLRDNORM)) { 947 IFQ_LOCK(&ifp->if_snd); 948 IFQ_POLL_NOLOCK(&ifp->if_snd, m); 949 if (m != NULL) { 950 TUNDEBUG(ifp, "tunpoll q=%d\n", ifp->if_snd.ifq_len); 951 revents |= events & (POLLIN | POLLRDNORM); 952 } else { 953 TUNDEBUG(ifp, "tunpoll waiting\n"); 954 selrecord(td, &tp->tun_rsel); 955 } 956 IFQ_UNLOCK(&ifp->if_snd); 957 } 958 if (events & (POLLOUT | POLLWRNORM)) 959 revents |= events & (POLLOUT | POLLWRNORM); 960 961 return (revents); 962} 963 964/* 965 * tunkqfilter - support for the kevent() system call. 966 */ 967static int 968tunkqfilter(struct cdev *dev, struct knote *kn) 969{ 970 struct tun_softc *tp = dev->si_drv1; 971 struct ifnet *ifp = TUN2IFP(tp); 972 973 switch(kn->kn_filter) { 974 case EVFILT_READ: 975 TUNDEBUG(ifp, "%s kqfilter: EVFILT_READ, minor = %#x\n", 976 ifp->if_xname, dev2unit(dev)); 977 kn->kn_fop = &tun_read_filterops; 978 break; 979 980 case EVFILT_WRITE: 981 TUNDEBUG(ifp, "%s kqfilter: EVFILT_WRITE, minor = %#x\n", 982 ifp->if_xname, dev2unit(dev)); 983 kn->kn_fop = &tun_write_filterops; 984 break; 985 986 default: 987 TUNDEBUG(ifp, "%s kqfilter: invalid filter, minor = %#x\n", 988 ifp->if_xname, dev2unit(dev)); 989 return(EINVAL); 990 } 991 992 kn->kn_hook = tp; 993 knlist_add(&tp->tun_rsel.si_note, kn, 0); 994 995 return (0); 996} 997 998/* 999 * Return true of there is data in the interface queue. 1000 */ 1001static int 1002tunkqread(struct knote *kn, long hint) 1003{ 1004 int ret; 1005 struct tun_softc *tp = kn->kn_hook; 1006 struct cdev *dev = tp->tun_dev; 1007 struct ifnet *ifp = TUN2IFP(tp); 1008 1009 if ((kn->kn_data = ifp->if_snd.ifq_len) > 0) { 1010 TUNDEBUG(ifp, 1011 "%s have data in the queue. Len = %d, minor = %#x\n", 1012 ifp->if_xname, ifp->if_snd.ifq_len, dev2unit(dev)); 1013 ret = 1; 1014 } else { 1015 TUNDEBUG(ifp, 1016 "%s waiting for data, minor = %#x\n", ifp->if_xname, 1017 dev2unit(dev)); 1018 ret = 0; 1019 } 1020 1021 return (ret); 1022} 1023 1024/* 1025 * Always can write, always return MTU in kn->data. 1026 */ 1027static int 1028tunkqwrite(struct knote *kn, long hint) 1029{ 1030 struct tun_softc *tp = kn->kn_hook; 1031 struct ifnet *ifp = TUN2IFP(tp); 1032 1033 kn->kn_data = ifp->if_mtu; 1034 1035 return (1); 1036} 1037 1038static void 1039tunkqdetach(struct knote *kn) 1040{ 1041 struct tun_softc *tp = kn->kn_hook; 1042 1043 knlist_remove(&tp->tun_rsel.si_note, kn, 0); 1044} 1045