sys/netgraph/ng_iface.c

   1 /*
   2  * ng_iface.c
   3  */
   4
   5 /*-
   6  * Copyright (c) 1996-1999 Whistle Communications, Inc.
   7  * All rights reserved.
   8  *
   9  * Subject to the following obligations and disclaimer of warranty, use and
  10  * redistribution of this software, in source or object code forms, with or
  11  * without modifications are expressly permitted by Whistle Communications;
  12  * provided, however, that:
  13  * 1. Any and all reproductions of the source or object code must include the
  14  *    copyright notice above and the following disclaimer of warranties; and
  15  * 2. No rights are granted, in any manner or form, to use Whistle
  16  *    Communications, Inc. trademarks, including the mark "WHISTLE
  17  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
  18  *    such appears in the above copyright notice or in the software.
  19  *
  20  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
  21  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
  22  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
  23  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
  24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
  25  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
  26  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
  27  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
  28  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
  29  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
  30  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  31  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
  32  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  35  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
  36  * OF SUCH DAMAGE.
  37  *
  38  * Author: Archie Cobbs <archie@freebsd.org>
  39  * $Whistle: ng_iface.c,v 1.33 1999/11/01 09:24:51 julian Exp $
  40  */
  41
  42 /*
  43  * This node is also a system networking interface. It has
  44  * a hook for each protocol (IP, AppleTalk, etc). Packets
  45  * are simply relayed between the interface and the hooks.
  46  *
  47  * Interfaces are named ng0, ng1, etc.  New nodes take the
  48  * first available interface name.
  49  *
  50  * This node also includes Berkeley packet filter support.
  51  */
  52
  53 #include "opt_inet.h"
  54 #include "opt_inet6.h"
  55
  56 #include <sys/param.h>
  57 #include <sys/systm.h>
  58 #include <sys/errno.h>
  59 #include <sys/kernel.h>
  60 #include <sys/lock.h>
  61 #include <sys/malloc.h>
  62 #include <sys/mbuf.h>
  63 #include <sys/errno.h>
  64 #include <sys/proc.h>
  65 #include <sys/random.h>
  66 #include <sys/rmlock.h>
  67 #include <sys/sockio.h>
  68 #include <sys/socket.h>
  69 #include <sys/sysctl.h>
  70 #include <sys/syslog.h>
  71 #include <sys/libkern.h>
  72
  73 #include <net/if.h>
  74 #include <net/if_var.h>
  75 #include <net/if_types.h>
  76 #include <net/bpf.h>
  77 #include <net/netisr.h>
  78 #include <net/route.h>
  79 #include <net/vnet.h>
  80
  81 #include <netinet/in.h>
  82
  83 #include <netgraph/ng_message.h>
  84 #include <netgraph/netgraph.h>
  85 #include <netgraph/ng_parse.h>
  86 #include <netgraph/ng_iface.h>
  87
  88 #ifdef NG_SEPARATE_MALLOC
  89 static MALLOC_DEFINE(M_NETGRAPH_IFACE, "netgraph_iface", "netgraph iface node");
  90 #else
  91 #define M_NETGRAPH_IFACE M_NETGRAPH
  92 #endif
  93
  94 static SYSCTL_NODE(_net_graph, OID_AUTO, iface, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
  95     "Point to point netgraph interface");
  96 VNET_DEFINE_STATIC(int, ng_iface_max_nest) = 2;
  97 #define V_ng_iface_max_nest     VNET(ng_iface_max_nest)
  98 SYSCTL_INT(_net_graph_iface, OID_AUTO, max_nesting, CTLFLAG_VNET | CTLFLAG_RW,
  99     &VNET_NAME(ng_iface_max_nest), 0, "Max nested tunnels");
 100
 101 /* This struct describes one address family */
 102 struct iffam {
 103         sa_family_t     family;         /* Address family */
 104         const char      *hookname;      /* Name for hook */
 105 };
 106 typedef const struct iffam *iffam_p;
 107
 108 /* List of address families supported by our interface */
 109 const static struct iffam gFamilies[] = {
 110         { AF_INET,      NG_IFACE_HOOK_INET      },
 111         { AF_INET6,     NG_IFACE_HOOK_INET6     },
 112 };
 113 #define NUM_FAMILIES            nitems(gFamilies)
 114
 115 /* Node private data */
 116 struct ng_iface_private {
 117         struct  ifnet *ifp;             /* Our interface */
 118         int     unit;                   /* Interface unit number */
 119         node_p  node;                   /* Our netgraph node */
 120         hook_p  hooks[NUM_FAMILIES];    /* Hook for each address family */
 121         struct rmlock   lock;           /* Protect private data changes */
 122 };
 123 typedef struct ng_iface_private *priv_p;
 124
 125 #define PRIV_RLOCK(priv, t)     rm_rlock(&priv->lock, t)
 126 #define PRIV_RUNLOCK(priv, t)   rm_runlock(&priv->lock, t)
 127 #define PRIV_WLOCK(priv)        rm_wlock(&priv->lock)
 128 #define PRIV_WUNLOCK(priv)      rm_wunlock(&priv->lock)
 129
 130 /* Interface methods */
 131 static void     ng_iface_start(struct ifnet *ifp);
 132 static int      ng_iface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
 133 static int      ng_iface_output(struct ifnet *ifp, struct mbuf *m0,
 134                         const struct sockaddr *dst, struct route *ro);
 135 static void     ng_iface_bpftap(struct ifnet *ifp,
 136                         struct mbuf *m, sa_family_t family);
 137 static int      ng_iface_send(struct ifnet *ifp, struct mbuf *m,
 138                         sa_family_t sa);
 139 #ifdef DEBUG
 140 static void     ng_iface_print_ioctl(struct ifnet *ifp, int cmd, caddr_t data);
 141 #endif
 142
 143 /* Netgraph methods */
 144 static int              ng_iface_mod_event(module_t, int, void *);
 145 static ng_constructor_t ng_iface_constructor;
 146 static ng_rcvmsg_t      ng_iface_rcvmsg;
 147 static ng_shutdown_t    ng_iface_shutdown;
 148 static ng_newhook_t     ng_iface_newhook;
 149 static ng_rcvdata_t     ng_iface_rcvdata;
 150 static ng_disconnect_t  ng_iface_disconnect;
 151
 152 /* Helper stuff */
 153 static iffam_p  get_iffam_from_af(sa_family_t family);
 154 static iffam_p  get_iffam_from_hook(priv_p priv, hook_p hook);
 155 static iffam_p  get_iffam_from_name(const char *name);
 156 static hook_p  *get_hook_from_iffam(priv_p priv, iffam_p iffam);
 157
 158 /* List of commands and how to convert arguments to/from ASCII */
 159 static const struct ng_cmdlist ng_iface_cmds[] = {
 160         {
 161           NGM_IFACE_COOKIE,
 162           NGM_IFACE_GET_IFNAME,
 163           "getifname",
 164           NULL,
 165           &ng_parse_string_type
 166         },
 167         {
 168           NGM_IFACE_COOKIE,
 169           NGM_IFACE_POINT2POINT,
 170           "point2point",
 171           NULL,
 172           NULL
 173         },
 174         {
 175           NGM_IFACE_COOKIE,
 176           NGM_IFACE_BROADCAST,
 177           "broadcast",
 178           NULL,
 179           NULL
 180         },
 181         {
 182           NGM_IFACE_COOKIE,
 183           NGM_IFACE_GET_IFINDEX,
 184           "getifindex",
 185           NULL,
 186           &ng_parse_uint32_type
 187         },
 188         { 0 }
 189 };
 190
 191 /* Node type descriptor */
 192 static struct ng_type typestruct = {
 193         .version =      NG_ABI_VERSION,
 194         .name =         NG_IFACE_NODE_TYPE,
 195         .mod_event =    ng_iface_mod_event,
 196         .constructor =  ng_iface_constructor,
 197         .rcvmsg =       ng_iface_rcvmsg,
 198         .shutdown =     ng_iface_shutdown,
 199         .newhook =      ng_iface_newhook,
 200         .rcvdata =      ng_iface_rcvdata,
 201         .disconnect =   ng_iface_disconnect,
 202         .cmdlist =      ng_iface_cmds,
 203 };
 204 NETGRAPH_INIT(iface, &typestruct);
 205
 206 VNET_DEFINE_STATIC(struct unrhdr *, ng_iface_unit);
 207 #define V_ng_iface_unit                 VNET(ng_iface_unit)
 208
 209 /************************************************************************
 210                         HELPER STUFF
 211  ************************************************************************/
 212
 213 /*
 214  * Get the family descriptor from the family ID
 215  */
 216 static __inline iffam_p
 217 get_iffam_from_af(sa_family_t family)
 218 {
 219         iffam_p iffam;
 220         int k;
 221
 222         for (k = 0; k < NUM_FAMILIES; k++) {
 223                 iffam = &gFamilies[k];
 224                 if (iffam->family == family)
 225                         return (iffam);
 226         }
 227         return (NULL);
 228 }
 229
 230 /*
 231  * Get the family descriptor from the hook
 232  */
 233 static __inline iffam_p
 234 get_iffam_from_hook(priv_p priv, hook_p hook)
 235 {
 236         int k;
 237
 238         for (k = 0; k < NUM_FAMILIES; k++)
 239                 if (priv->hooks[k] == hook)
 240                         return (&gFamilies[k]);
 241         return (NULL);
 242 }
 243
 244 /*
 245  * Get the hook from the iffam descriptor
 246  */
 247
 248 static __inline hook_p *
 249 get_hook_from_iffam(priv_p priv, iffam_p iffam)
 250 {
 251         return (&priv->hooks[iffam - gFamilies]);
 252 }
 253
 254 /*
 255  * Get the iffam descriptor from the name
 256  */
 257 static __inline iffam_p
 258 get_iffam_from_name(const char *name)
 259 {
 260         iffam_p iffam;
 261         int k;
 262
 263         for (k = 0; k < NUM_FAMILIES; k++) {
 264                 iffam = &gFamilies[k];
 265                 if (!strcmp(iffam->hookname, name))
 266                         return (iffam);
 267         }
 268         return (NULL);
 269 }
 270
 271 /************************************************************************
 272                         INTERFACE STUFF
 273  ************************************************************************/
 274
 275 /*
 276  * Process an ioctl for the virtual interface
 277  */
 278 static int
 279 ng_iface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
 280 {
 281         struct ifreq *const ifr = (struct ifreq *) data;
 282         int error = 0;
 283
 284 #ifdef DEBUG
 285         ng_iface_print_ioctl(ifp, command, data);
 286 #endif
 287         switch (command) {
 288         /* These two are mostly handled at a higher layer */
 289         case SIOCSIFADDR:
 290                 ifp->if_flags |= IFF_UP;
 291                 ifp->if_drv_flags |= IFF_DRV_RUNNING;
 292                 ifp->if_drv_flags &= ~(IFF_DRV_OACTIVE);
 293                 break;
 294         case SIOCGIFADDR:
 295                 break;
 296
 297         /* Set flags */
 298         case SIOCSIFFLAGS:
 299                 /*
 300                  * If the interface is marked up and stopped, then start it.
 301                  * If it is marked down and running, then stop it.
 302                  */
 303                 if (ifr->ifr_flags & IFF_UP) {
 304                         if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) {
 305                                 ifp->if_drv_flags &= ~(IFF_DRV_OACTIVE);
 306                                 ifp->if_drv_flags |= IFF_DRV_RUNNING;
 307                         }
 308                 } else {
 309                         if (ifp->if_drv_flags & IFF_DRV_RUNNING)
 310                                 ifp->if_drv_flags &= ~(IFF_DRV_RUNNING |
 311                                     IFF_DRV_OACTIVE);
 312                 }
 313                 break;
 314
 315         /* Set the interface MTU */
 316         case SIOCSIFMTU:
 317                 if (ifr->ifr_mtu > NG_IFACE_MTU_MAX
 318                     || ifr->ifr_mtu < NG_IFACE_MTU_MIN)
 319                         error = EINVAL;
 320                 else
 321                         ifp->if_mtu = ifr->ifr_mtu;
 322                 break;
 323
 324         /* Stuff that's not supported */
 325         case SIOCADDMULTI:
 326         case SIOCDELMULTI:
 327                 error = 0;
 328                 break;
 329         case SIOCSIFPHYS:
 330                 error = EOPNOTSUPP;
 331                 break;
 332
 333         default:
 334                 error = EINVAL;
 335                 break;
 336         }
 337         return (error);
 338 }
 339
 340 /*
 341  * This routine is called to deliver a packet out the interface.
 342  * We simply look at the address family and relay the packet to
 343  * the corresponding hook, if it exists and is connected.
 344  */
 345
 346 static int
 347 ng_iface_output(struct ifnet *ifp, struct mbuf *m,
 348         const struct sockaddr *dst, struct route *ro)
 349 {
 350         uint32_t af;
 351         int error;
 352
 353         /* Check interface flags */
 354         if (!((ifp->if_flags & IFF_UP) &&
 355             (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
 356                 m_freem(m);
 357                 return (ENETDOWN);
 358         }
 359
 360         /* Protect from deadly infinite recursion. */
 361         error = if_tunnel_check_nesting(ifp, m, NGM_IFACE_COOKIE,
 362             V_ng_iface_max_nest);
 363         if (error) {
 364                 m_freem(m);
 365                 return (error);
 366         }
 367
 368         /* BPF writes need to be handled specially. */
 369         if (dst->sa_family == AF_UNSPEC)
 370                 bcopy(dst->sa_data, &af, sizeof(af));
 371         else
 372                 af = RO_GET_FAMILY(ro, dst);
 373
 374         /* Berkeley packet filter */
 375         ng_iface_bpftap(ifp, m, af);
 376
 377         if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
 378                 M_PREPEND(m, sizeof(sa_family_t), M_NOWAIT);
 379                 if (m == NULL) {
 380                         if_inc_counter(ifp, IFCOUNTER_OQDROPS, 1);
 381                         return (ENOBUFS);
 382                 }
 383                 *(sa_family_t *)m->m_data = af;
 384                 error = (ifp->if_transmit)(ifp, m);
 385         } else
 386                 error = ng_iface_send(ifp, m, af);
 387
 388         return (error);
 389 }
 390
 391 /*
 392  * Start method is used only when ALTQ is enabled.
 393  */
 394 static void
 395 ng_iface_start(struct ifnet *ifp)
 396 {
 397         struct mbuf *m;
 398         sa_family_t sa;
 399
 400         KASSERT(ALTQ_IS_ENABLED(&ifp->if_snd), ("%s without ALTQ", __func__));
 401
 402         for(;;) {
 403                 IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
 404                 if (m == NULL)
 405                         break;
 406                 sa = *mtod(m, sa_family_t *);
 407                 m_adj(m, sizeof(sa_family_t));
 408                 ng_iface_send(ifp, m, sa);
 409         }
 410 }
 411
 412 /*
 413  * Flash a packet by the BPF (requires prepending 4 byte AF header)
 414  * Note the phoney mbuf; this is OK because BPF treats it read-only.
 415  */
 416 static void
 417 ng_iface_bpftap(struct ifnet *ifp, struct mbuf *m, sa_family_t family)
 418 {
 419         KASSERT(family != AF_UNSPEC, ("%s: family=AF_UNSPEC", __func__));
 420         if (bpf_peers_present(ifp->if_bpf)) {
 421                 int32_t family4 = (int32_t)family;
 422                 bpf_mtap2(ifp->if_bpf, &family4, sizeof(family4), m);
 423         }
 424 }
 425
 426 /*
 427  * This routine does actual delivery of the packet into the
 428  * netgraph(4). It is called from ng_iface_start() and
 429  * ng_iface_output().
 430  */
 431 static int
 432 ng_iface_send(struct ifnet *ifp, struct mbuf *m, sa_family_t sa)
 433 {
 434         struct rm_priotracker priv_tracker;
 435         const priv_p priv = (priv_p) ifp->if_softc;
 436         const iffam_p iffam = get_iffam_from_af(sa);
 437         hook_p hook;
 438         int error;
 439         int len;
 440
 441         /* Check address family to determine hook (if known) */
 442         if (iffam == NULL) {
 443                 m_freem(m);
 444                 log(LOG_WARNING, "%s: can't handle af%d\n", ifp->if_xname, sa);
 445                 return (EAFNOSUPPORT);
 446         }
 447
 448         /* Copy length before the mbuf gets invalidated. */
 449         len = m->m_pkthdr.len;
 450
 451         PRIV_RLOCK(priv, &priv_tracker);
 452         hook = *get_hook_from_iffam(priv, iffam);
 453         if (hook == NULL) {
 454                 NG_FREE_M(m);
 455                 PRIV_RUNLOCK(priv, &priv_tracker);
 456                 return ENETDOWN;
 457         }
 458         NG_HOOK_REF(hook);
 459         PRIV_RUNLOCK(priv, &priv_tracker);
 460
 461         NG_OUTBOUND_THREAD_REF();
 462         NG_SEND_DATA_ONLY(error, hook, m);
 463         NG_OUTBOUND_THREAD_UNREF();
 464         NG_HOOK_UNREF(hook);
 465
 466         /* Update stats. */
 467         if (error == 0) {
 468                 if_inc_counter(ifp, IFCOUNTER_OBYTES, len);
 469                 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
 470         }
 471
 472         return (error);
 473 }
 474
 475 #ifdef DEBUG
 476 /*
 477  * Display an ioctl to the virtual interface
 478  */
 479
 480 static void
 481 ng_iface_print_ioctl(struct ifnet *ifp, int command, caddr_t data)
 482 {
 483         char   *str;
 484
 485         switch (command & IOC_DIRMASK) {
 486         case IOC_VOID:
 487                 str = "IO";
 488                 break;
 489         case IOC_OUT:
 490                 str = "IOR";
 491                 break;
 492         case IOC_IN:
 493                 str = "IOW";
 494                 break;
 495         case IOC_INOUT:
 496                 str = "IORW";
 497                 break;
 498         default:
 499                 str = "IO??";
 500         }
 501         log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
 502                ifp->if_xname,
 503                str,
 504                IOCGROUP(command),
 505                command & 0xff,
 506                IOCPARM_LEN(command));
 507 }
 508 #endif /* DEBUG */
 509
 510 /************************************************************************
 511                         NETGRAPH NODE STUFF
 512  ************************************************************************/
 513
 514 /*
 515  * Constructor for a node
 516  */
 517 static int
 518 ng_iface_constructor(node_p node)
 519 {
 520         struct ifnet *ifp;
 521         priv_p priv;
 522
 523         /* Allocate node and interface private structures */
 524         priv = malloc(sizeof(*priv), M_NETGRAPH_IFACE, M_WAITOK | M_ZERO);
 525         ifp = if_alloc(IFT_PROPVIRTUAL);
 526         if (ifp == NULL) {
 527                 free(priv, M_NETGRAPH_IFACE);
 528                 return (ENOMEM);
 529         }
 530
 531         rm_init(&priv->lock, "ng_iface private rmlock");
 532
 533         /* Link them together */
 534         ifp->if_softc = priv;
 535         priv->ifp = ifp;
 536
 537         /* Get an interface unit number */
 538         priv->unit = alloc_unr(V_ng_iface_unit);
 539
 540         /* Link together node and private info */
 541         NG_NODE_SET_PRIVATE(node, priv);
 542         priv->node = node;
 543
 544         /* Initialize interface structure */
 545         if_initname(ifp, NG_IFACE_IFACE_NAME, priv->unit);
 546         ifp->if_output = ng_iface_output;
 547         ifp->if_start = ng_iface_start;
 548         ifp->if_ioctl = ng_iface_ioctl;
 549         ifp->if_mtu = NG_IFACE_MTU_DEFAULT;
 550         ifp->if_flags = (IFF_SIMPLEX|IFF_POINTOPOINT|IFF_NOARP|IFF_MULTICAST);
 551         ifp->if_type = IFT_PROPVIRTUAL;         /* XXX */
 552         ifp->if_addrlen = 0;                    /* XXX */
 553         ifp->if_hdrlen = 0;                     /* XXX */
 554         ifp->if_baudrate = 64000;               /* XXX */
 555         IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
 556         ifp->if_snd.ifq_drv_maxlen = ifqmaxlen;
 557         IFQ_SET_READY(&ifp->if_snd);
 558
 559         /* Give this node the same name as the interface (if possible) */
 560         if (ng_name_node(node, ifp->if_xname) != 0)
 561                 log(LOG_WARNING, "%s: can't acquire netgraph name\n",
 562                     ifp->if_xname);
 563
 564         /* Attach the interface */
 565         if_attach(ifp);
 566         bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
 567
 568         /* Done */
 569         return (0);
 570 }
 571
 572 /*
 573  * Give our ok for a hook to be added
 574  */
 575 static int
 576 ng_iface_newhook(node_p node, hook_p hook, const char *name)
 577 {
 578         const iffam_p iffam = get_iffam_from_name(name);
 579         const priv_p priv = NG_NODE_PRIVATE(node);
 580         hook_p *hookptr;
 581
 582         if (iffam == NULL)
 583                 return (EPFNOSUPPORT);
 584         PRIV_WLOCK(priv);
 585         hookptr = get_hook_from_iffam(priv, iffam);
 586         if (*hookptr != NULL) {
 587                 PRIV_WUNLOCK(priv);
 588                 return (EISCONN);
 589         }
 590         *hookptr = hook;
 591         NG_HOOK_HI_STACK(hook);
 592         NG_HOOK_SET_TO_INBOUND(hook);
 593         PRIV_WUNLOCK(priv);
 594         return (0);
 595 }
 596
 597 /*
 598  * Receive a control message
 599  */
 600 static int
 601 ng_iface_rcvmsg(node_p node, item_p item, hook_p lasthook)
 602 {
 603         const priv_p priv = NG_NODE_PRIVATE(node);
 604         struct ifnet *const ifp = priv->ifp;
 605         struct ng_mesg *resp = NULL;
 606         int error = 0;
 607         struct ng_mesg *msg;
 608
 609         NGI_GET_MSG(item, msg);
 610         switch (msg->header.typecookie) {
 611         case NGM_IFACE_COOKIE:
 612                 switch (msg->header.cmd) {
 613                 case NGM_IFACE_GET_IFNAME:
 614                         NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
 615                         if (resp == NULL) {
 616                                 error = ENOMEM;
 617                                 break;
 618                         }
 619                         strlcpy(resp->data, ifp->if_xname, IFNAMSIZ);
 620                         break;
 621
 622                 case NGM_IFACE_POINT2POINT:
 623                 case NGM_IFACE_BROADCAST:
 624                     {
 625                         /* Deny request if interface is UP */
 626                         if ((ifp->if_flags & IFF_UP) != 0)
 627                                 return (EBUSY);
 628
 629                         /* Change flags */
 630                         switch (msg->header.cmd) {
 631                         case NGM_IFACE_POINT2POINT:
 632                                 ifp->if_flags |= IFF_POINTOPOINT;
 633                                 ifp->if_flags &= ~IFF_BROADCAST;
 634                                 break;
 635                         case NGM_IFACE_BROADCAST:
 636                                 ifp->if_flags &= ~IFF_POINTOPOINT;
 637                                 ifp->if_flags |= IFF_BROADCAST;
 638                                 break;
 639                         }
 640                         break;
 641                     }
 642
 643                 case NGM_IFACE_GET_IFINDEX:
 644                         NG_MKRESPONSE(resp, msg, sizeof(uint32_t), M_NOWAIT);
 645                         if (resp == NULL) {
 646                                 error = ENOMEM;
 647                                 break;
 648                         }
 649                         *((uint32_t *)resp->data) = priv->ifp->if_index;
 650                         break;
 651
 652                 default:
 653                         error = EINVAL;
 654                         break;
 655                 }
 656                 break;
 657         case NGM_FLOW_COOKIE:
 658                 switch (msg->header.cmd) {
 659                 case NGM_LINK_IS_UP:
 660                         if_link_state_change(ifp, LINK_STATE_UP);
 661                         break;
 662                 case NGM_LINK_IS_DOWN:
 663                         if_link_state_change(ifp, LINK_STATE_DOWN);
 664                         break;
 665                 default:
 666                         break;
 667                 }
 668                 break;
 669         default:
 670                 error = EINVAL;
 671                 break;
 672         }
 673         NG_RESPOND_MSG(error, node, item, resp);
 674         NG_FREE_MSG(msg);
 675         return (error);
 676 }
 677
 678 /*
 679  * Recive data from a hook. Pass the packet to the correct input routine.
 680  */
 681 static int
 682 ng_iface_rcvdata(hook_p hook, item_p item)
 683 {
 684         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 685         const iffam_p iffam = get_iffam_from_hook(priv, hook);
 686         struct ifnet *const ifp = priv->ifp;
 687         struct epoch_tracker et;
 688         struct mbuf *m;
 689         int isr;
 690
 691         NGI_GET_M(item, m);
 692         NG_FREE_ITEM(item);
 693         /* Sanity checks */
 694         KASSERT(iffam != NULL, ("%s: iffam", __func__));
 695         M_ASSERTPKTHDR(m);
 696         if ((ifp->if_flags & IFF_UP) == 0) {
 697                 NG_FREE_M(m);
 698                 return (ENETDOWN);
 699         }
 700
 701         /* Update interface stats */
 702         if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
 703         if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len);
 704
 705         /* Note receiving interface */
 706         m->m_pkthdr.rcvif = ifp;
 707
 708         /* Berkeley packet filter */
 709         ng_iface_bpftap(ifp, m, iffam->family);
 710
 711         /* Send packet */
 712         switch (iffam->family) {
 713 #ifdef INET
 714         case AF_INET:
 715                 isr = NETISR_IP;
 716                 break;
 717 #endif
 718 #ifdef INET6
 719         case AF_INET6:
 720                 isr = NETISR_IPV6;
 721                 break;
 722 #endif
 723         default:
 724                 m_freem(m);
 725                 return (EAFNOSUPPORT);
 726         }
 727         random_harvest_queue(m, sizeof(*m), RANDOM_NET_NG);
 728         M_SETFIB(m, ifp->if_fib);
 729         CURVNET_SET(ifp->if_vnet);
 730         NET_EPOCH_ENTER(et);
 731         netisr_dispatch(isr, m);
 732         NET_EPOCH_EXIT(et);
 733         CURVNET_RESTORE();
 734         return (0);
 735 }
 736
 737 /*
 738  * Shutdown and remove the node and its associated interface.
 739  */
 740 static int
 741 ng_iface_shutdown(node_p node)
 742 {
 743         const priv_p priv = NG_NODE_PRIVATE(node);
 744
 745         /*
 746          * The ifnet may be in a different vnet than the netgraph node,
 747          * hence we have to change the current vnet context here.
 748          */
 749         CURVNET_SET_QUIET(priv->ifp->if_vnet);
 750         bpfdetach(priv->ifp);
 751         if_detach(priv->ifp);
 752         if_free(priv->ifp);
 753         CURVNET_RESTORE();
 754         priv->ifp = NULL;
 755         free_unr(V_ng_iface_unit, priv->unit);
 756         rm_destroy(&priv->lock);
 757         free(priv, M_NETGRAPH_IFACE);
 758         NG_NODE_SET_PRIVATE(node, NULL);
 759         NG_NODE_UNREF(node);
 760         return (0);
 761 }
 762
 763 /*
 764  * Hook disconnection. Note that we do *not* shutdown when all
 765  * hooks have been disconnected.
 766  */
 767 static int
 768 ng_iface_disconnect(hook_p hook)
 769 {
 770         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 771         const iffam_p iffam = get_iffam_from_hook(priv, hook);
 772
 773         if (iffam == NULL)
 774                 panic("%s", __func__);
 775         PRIV_WLOCK(priv);
 776         *get_hook_from_iffam(priv, iffam) = NULL;
 777         PRIV_WUNLOCK(priv);
 778         return (0);
 779 }
 780
 781 /*
 782  * Handle loading and unloading for this node type.
 783  */
 784 static int
 785 ng_iface_mod_event(module_t mod, int event, void *data)
 786 {
 787         int error = 0;
 788
 789         switch (event) {
 790         case MOD_LOAD:
 791         case MOD_UNLOAD:
 792                 break;
 793         default:
 794                 error = EOPNOTSUPP;
 795                 break;
 796         }
 797         return (error);
 798 }
 799
 800 static void
 801 vnet_ng_iface_init(const void *unused)
 802 {
 803
 804         V_ng_iface_unit = new_unrhdr(0, 0xffff, NULL);
 805 }
 806 VNET_SYSINIT(vnet_ng_iface_init, SI_SUB_PSEUDO, SI_ORDER_ANY,
 807     vnet_ng_iface_init, NULL);
 808
 809 static void
 810 vnet_ng_iface_uninit(const void *unused)
 811 {
 812
 813         delete_unrhdr(V_ng_iface_unit);
 814 }
 815 VNET_SYSUNINIT(vnet_ng_iface_uninit, SI_SUB_INIT_IF, SI_ORDER_ANY,
 816     vnet_ng_iface_uninit, NULL);