sys/netgraph7/ng_ether.c

   1
   2 /*
   3  * ng_ether.c
   4  */
   5
   6 /*-
   7  * Copyright (c) 1996-2000 Whistle Communications, Inc.
   8  * All rights reserved.
   9  *
  10  * Subject to the following obligations and disclaimer of warranty, use and
  11  * redistribution of this software, in source or object code forms, with or
  12  * without modifications are expressly permitted by Whistle Communications;
  13  * provided, however, that:
  14  * 1. Any and all reproductions of the source or object code must include the
  15  *    copyright notice above and the following disclaimer of warranties; and
  16  * 2. No rights are granted, in any manner or form, to use Whistle
  17  *    Communications, Inc. trademarks, including the mark "WHISTLE
  18  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
  19  *    such appears in the above copyright notice or in the software.
  20  *
  21  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
  22  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
  23  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
  24  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
  26  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
  27  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
  28  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
  29  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
  30  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
  31  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  32  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
  33  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
  34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  36  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
  37  * OF SUCH DAMAGE.
  38  *
  39  * Authors: Archie Cobbs <archie@freebsd.org>
  40  *          Julian Elischer <julian@freebsd.org>
  41  *
  42  * $FreeBSD: src/sys/netgraph/ng_ether.c,v 1.62 2007/03/20 00:36:10 bms Exp $
  43  * $DragonFly: src/sys/netgraph7/ng_ether.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
  44  */
  45
  46 /*
  47  * ng_ether(4) netgraph node type
  48  */
  49
  50 #include <sys/param.h>
  51 #include <sys/systm.h>
  52 #include <sys/kernel.h>
  53 #include <sys/malloc.h>
  54 #include <sys/mbuf.h>
  55 #include <sys/errno.h>
  56 #include <sys/syslog.h>
  57 #include <sys/socket.h>
  58
  59 #include <net/if.h>
  60 #include <net/if_dl.h>
  61 #include <net/if_types.h>
  62 #include <net/if_arp.h>
  63 #include <net/if_var.h>
  64 #include <net/ethernet.h>
  65 #include <net/if_bridgevar.h>
  66
  67 #include "ng_message.h"
  68 #include "netgraph.h"
  69 #include "ng_parse.h"
  70 #include "ng_ether.h"
  71
  72 #define IFP2NG(ifp)  (IFP2AC((ifp))->ac_netgraph)
  73
  74 /* Per-node private data */
  75 struct private {
  76         struct ifnet    *ifp;           /* associated interface */
  77         hook_p          upper;          /* upper hook connection */
  78         hook_p          lower;          /* lower hook connection */
  79         hook_p          orphan;         /* orphan hook connection */
  80         u_char          autoSrcAddr;    /* always overwrite source address */
  81         u_char          promisc;        /* promiscuous mode enabled */
  82         u_long          hwassist;       /* hardware checksum capabilities */
  83         u_int           flags;          /* flags e.g. really die */
  84 };
  85 typedef struct private *priv_p;
  86
  87 /* Hook pointers used by if_ethersubr.c to callback to netgraph */
  88 extern  void    (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
  89 extern  void    (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m);
  90 extern  int     (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
  91 extern  void    (*ng_ether_attach_p)(struct ifnet *ifp);
  92 extern  void    (*ng_ether_detach_p)(struct ifnet *ifp);
  93 extern  void    (*ng_ether_link_state_p)(struct ifnet *ifp, int state);
  94
  95 /* Functional hooks called from if_ethersubr.c */
  96 static void     ng_ether_input(struct ifnet *ifp, struct mbuf **mp);
  97 static void     ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m);
  98 static int      ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
  99 static void     ng_ether_attach(struct ifnet *ifp);
 100 static void     ng_ether_detach(struct ifnet *ifp);
 101 static void     ng_ether_link_state(struct ifnet *ifp, int state);
 102
 103 /* Other functions */
 104 static int      ng_ether_rcv_lower(node_p node, struct mbuf *m);
 105 static int      ng_ether_rcv_upper(node_p node, struct mbuf *m);
 106
 107 /* Netgraph node methods */
 108 static ng_constructor_t ng_ether_constructor;
 109 static ng_rcvmsg_t      ng_ether_rcvmsg;
 110 static ng_shutdown_t    ng_ether_shutdown;
 111 static ng_newhook_t     ng_ether_newhook;
 112 static ng_rcvdata_t     ng_ether_rcvdata;
 113 static ng_disconnect_t  ng_ether_disconnect;
 114 static int              ng_ether_mod_event(module_t mod, int event, void *data);
 115
 116 /* List of commands and how to convert arguments to/from ASCII */
 117 static const struct ng_cmdlist ng_ether_cmdlist[] = {
 118         {
 119           NGM_ETHER_COOKIE,
 120           NGM_ETHER_GET_IFNAME,
 121           "getifname",
 122           NULL,
 123           &ng_parse_string_type
 124         },
 125         {
 126           NGM_ETHER_COOKIE,
 127           NGM_ETHER_GET_IFINDEX,
 128           "getifindex",
 129           NULL,
 130           &ng_parse_int32_type
 131         },
 132         {
 133           NGM_ETHER_COOKIE,
 134           NGM_ETHER_GET_ENADDR,
 135           "getenaddr",
 136           NULL,
 137           &ng_parse_enaddr_type
 138         },
 139         {
 140           NGM_ETHER_COOKIE,
 141           NGM_ETHER_SET_ENADDR,
 142           "setenaddr",
 143           &ng_parse_enaddr_type,
 144           NULL
 145         },
 146         {
 147           NGM_ETHER_COOKIE,
 148           NGM_ETHER_GET_PROMISC,
 149           "getpromisc",
 150           NULL,
 151           &ng_parse_int32_type
 152         },
 153         {
 154           NGM_ETHER_COOKIE,
 155           NGM_ETHER_SET_PROMISC,
 156           "setpromisc",
 157           &ng_parse_int32_type,
 158           NULL
 159         },
 160         {
 161           NGM_ETHER_COOKIE,
 162           NGM_ETHER_GET_AUTOSRC,
 163           "getautosrc",
 164           NULL,
 165           &ng_parse_int32_type
 166         },
 167         {
 168           NGM_ETHER_COOKIE,
 169           NGM_ETHER_SET_AUTOSRC,
 170           "setautosrc",
 171           &ng_parse_int32_type,
 172           NULL
 173         },
 174         {
 175           NGM_ETHER_COOKIE,
 176           NGM_ETHER_ADD_MULTI,
 177           "addmulti",
 178           &ng_parse_enaddr_type,
 179           NULL
 180         },
 181         {
 182           NGM_ETHER_COOKIE,
 183           NGM_ETHER_DEL_MULTI,
 184           "delmulti",
 185           &ng_parse_enaddr_type,
 186           NULL
 187         },
 188         {
 189           NGM_ETHER_COOKIE,
 190           NGM_ETHER_DETACH,
 191           "detach",
 192           NULL,
 193           NULL
 194         },
 195         { 0 }
 196 };
 197
 198 static struct ng_type ng_ether_typestruct = {
 199         .version =      NG_ABI_VERSION,
 200         .name =         NG_ETHER_NODE_TYPE,
 201         .mod_event =    ng_ether_mod_event,
 202         .constructor =  ng_ether_constructor,
 203         .rcvmsg =       ng_ether_rcvmsg,
 204         .shutdown =     ng_ether_shutdown,
 205         .newhook =      ng_ether_newhook,
 206         .rcvdata =      ng_ether_rcvdata,
 207         .disconnect =   ng_ether_disconnect,
 208         .cmdlist =      ng_ether_cmdlist,
 209 };
 210 NETGRAPH_INIT(ether, &ng_ether_typestruct);
 211
 212 /******************************************************************
 213                     ETHERNET FUNCTION HOOKS
 214 ******************************************************************/
 215
 216 /*
 217  * Handle a packet that has come in on an interface. We get to
 218  * look at it here before any upper layer protocols do.
 219  *
 220  * NOTE: this function will get called at splimp()
 221  */
 222 static void
 223 ng_ether_input(struct ifnet *ifp, struct mbuf **mp)
 224 {
 225         const node_p node = IFP2NG(ifp);
 226         const priv_p priv = NG_NODE_PRIVATE(node);
 227         int error;
 228
 229         /* If "lower" hook not connected, let packet continue */
 230         if (priv->lower == NULL)
 231                 return;
 232         NG_SEND_DATA_ONLY(error, priv->lower, *mp);     /* sets *mp = NULL */
 233 }
 234
 235 /*
 236  * Handle a packet that has come in on an interface, and which
 237  * does not match any of our known protocols (an ``orphan'').
 238  *
 239  * NOTE: this function will get called at splimp()
 240  */
 241 static void
 242 ng_ether_input_orphan(struct ifnet *ifp, struct mbuf *m)
 243 {
 244         const node_p node = IFP2NG(ifp);
 245         const priv_p priv = NG_NODE_PRIVATE(node);
 246         int error;
 247
 248         /* If "orphan" hook not connected, discard packet */
 249         if (priv->orphan == NULL) {
 250                 m_freem(m);
 251                 return;
 252         }
 253         NG_SEND_DATA_ONLY(error, priv->orphan, m);
 254 }
 255
 256 /*
 257  * Handle a packet that is going out on an interface.
 258  * The Ethernet header is already attached to the mbuf.
 259  */
 260 static int
 261 ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
 262 {
 263         const node_p node = IFP2NG(ifp);
 264         const priv_p priv = NG_NODE_PRIVATE(node);
 265         int error = 0;
 266
 267         /* If "upper" hook not connected, let packet continue */
 268         if (priv->upper == NULL)
 269                 return (0);
 270
 271         /* Send it out "upper" hook */
 272         NG_SEND_DATA_ONLY(error, priv->upper, *mp);
 273         return (error);
 274 }
 275
 276 /*
 277  * A new Ethernet interface has been attached.
 278  * Create a new node for it, etc.
 279  */
 280 static void
 281 ng_ether_attach(struct ifnet *ifp)
 282 {
 283         priv_p priv;
 284         node_p node;
 285
 286         /* Create node */
 287         KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
 288         if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
 289                 log(LOG_ERR, "%s: can't %s for %s\n",
 290                     __func__, "create node", ifp->if_xname);
 291                 return;
 292         }
 293
 294         /* Allocate private data */
 295         MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK | M_NULLOK | M_ZERO);
 296         if (priv == NULL) {
 297                 log(LOG_ERR, "%s: can't %s for %s\n",
 298                     __func__, "allocate memory", ifp->if_xname);
 299                 NG_NODE_UNREF(node);
 300                 return;
 301         }
 302         NG_NODE_SET_PRIVATE(node, priv);
 303         priv->ifp = ifp;
 304         IFP2NG(ifp) = node;
 305         priv->hwassist = ifp->if_hwassist;
 306
 307         /* Try to give the node the same name as the interface */
 308         if (ng_name_node(node, ifp->if_xname) != 0) {
 309                 log(LOG_WARNING, "%s: can't name node %s\n",
 310                     __func__, ifp->if_xname);
 311         }
 312 }
 313
 314 /*
 315  * An Ethernet interface is being detached.
 316  * REALLY Destroy its node.
 317  */
 318 static void
 319 ng_ether_detach(struct ifnet *ifp)
 320 {
 321         const node_p node = IFP2NG(ifp);
 322         const priv_p priv = NG_NODE_PRIVATE(node);
 323
 324         NG_NODE_REALLY_DIE(node);       /* Force real removal of node */
 325         /*
 326          * We can't assume the ifnet is still around when we run shutdown
 327          * So zap it now. XXX We HOPE that anything running at this time
 328          * handles it (as it should in the non netgraph case).
 329          */
 330         IFP2NG(ifp) = NULL;
 331         priv->ifp = NULL;       /* XXX race if interrupted an output packet */
 332         ng_rmnode_self(node);           /* remove all netgraph parts */
 333 }
 334
 335 /*
 336  * Notify graph about link event.
 337  * if_link_state_change() has already checked that the state has changed.
 338  */
 339 static void
 340 ng_ether_link_state(struct ifnet *ifp, int state)
 341 {
 342         const node_p node = IFP2NG(ifp);
 343         const priv_p priv = NG_NODE_PRIVATE(node);
 344         struct ng_mesg *msg;
 345         int cmd, dummy_error = 0;
 346
 347         if (priv->lower == NULL)
 348                 return;
 349
 350         if (state == LINK_STATE_UP)
 351                 cmd = NGM_LINK_IS_UP;
 352         else if (state == LINK_STATE_DOWN)
 353                 cmd = NGM_LINK_IS_DOWN;
 354         else
 355                 return;
 356
 357         NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_WAITOK | M_NULLOK);
 358         if (msg != NULL)
 359                 NG_SEND_MSG_HOOK(dummy_error, node, msg, priv->lower, 0);
 360 }
 361
 362 /******************************************************************
 363                     NETGRAPH NODE METHODS
 364 ******************************************************************/
 365
 366 /*
 367  * It is not possible or allowable to create a node of this type.
 368  * Nodes get created when the interface is attached (or, when
 369  * this node type's KLD is loaded).
 370  */
 371 static int
 372 ng_ether_constructor(node_p node)
 373 {
 374         return (EINVAL);
 375 }
 376
 377 /*
 378  * Check for attaching a new hook.
 379  */
 380 static  int
 381 ng_ether_newhook(node_p node, hook_p hook, const char *name)
 382 {
 383         const priv_p priv = NG_NODE_PRIVATE(node);
 384         hook_p *hookptr;
 385
 386         /* Divert hook is an alias for lower */
 387         if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
 388                 name = NG_ETHER_HOOK_LOWER;
 389
 390         /* Which hook? */
 391         if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
 392                 hookptr = &priv->upper;
 393         else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0)
 394                 hookptr = &priv->lower;
 395         else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0)
 396                 hookptr = &priv->orphan;
 397         else
 398                 return (EINVAL);
 399
 400         /* Check if already connected (shouldn't be, but doesn't hurt) */
 401         if (*hookptr != NULL)
 402                 return (EISCONN);
 403
 404         /* Disable hardware checksums while 'upper' hook is connected */
 405         if (hookptr == &priv->upper)
 406                 priv->ifp->if_hwassist = 0;
 407
 408         /* OK */
 409         *hookptr = hook;
 410         return (0);
 411 }
 412
 413 /*
 414  * Receive an incoming control message.
 415  */
 416 static int
 417 ng_ether_rcvmsg(node_p node, item_p item, hook_p lasthook)
 418 {
 419         const priv_p priv = NG_NODE_PRIVATE(node);
 420         struct ng_mesg *resp = NULL;
 421         int error = 0;
 422         struct ng_mesg *msg;
 423
 424         NGI_GET_MSG(item, msg);
 425         switch (msg->header.typecookie) {
 426         case NGM_ETHER_COOKIE:
 427                 switch (msg->header.cmd) {
 428                 case NGM_ETHER_GET_IFNAME:
 429                         NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_WAITOK | M_NULLOK);
 430                         if (resp == NULL) {
 431                                 error = ENOMEM;
 432                                 break;
 433                         }
 434                         strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ);
 435                         break;
 436                 case NGM_ETHER_GET_IFINDEX:
 437                         NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_WAITOK | M_NULLOK);
 438                         if (resp == NULL) {
 439                                 error = ENOMEM;
 440                                 break;
 441                         }
 442                         *((u_int32_t *)resp->data) = priv->ifp->if_index;
 443                         break;
 444                 case NGM_ETHER_GET_ENADDR:
 445                         NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_WAITOK | M_NULLOK);
 446                         if (resp == NULL) {
 447                                 error = ENOMEM;
 448                                 break;
 449                         }
 450                         bcopy(IF_LLADDR(priv->ifp),
 451                             resp->data, ETHER_ADDR_LEN);
 452                         break;
 453                 case NGM_ETHER_SET_ENADDR:
 454                     {
 455                         if (msg->header.arglen != ETHER_ADDR_LEN) {
 456                                 error = EINVAL;
 457                                 break;
 458                         }
 459                         error = if_setlladdr(priv->ifp,
 460                             (u_char *)msg->data, ETHER_ADDR_LEN);
 461                         break;
 462                     }
 463                 case NGM_ETHER_GET_PROMISC:
 464                         NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_WAITOK | M_NULLOK);
 465                         if (resp == NULL) {
 466                                 error = ENOMEM;
 467                                 break;
 468                         }
 469                         *((u_int32_t *)resp->data) = priv->promisc;
 470                         break;
 471                 case NGM_ETHER_SET_PROMISC:
 472                     {
 473                         u_char want;
 474
 475                         if (msg->header.arglen != sizeof(u_int32_t)) {
 476                                 error = EINVAL;
 477                                 break;
 478                         }
 479                         want = !!*((u_int32_t *)msg->data);
 480                         if (want ^ priv->promisc) {
 481                                 if ((error = ifpromisc(priv->ifp, want)) != 0)
 482                                         break;
 483                                 priv->promisc = want;
 484                         }
 485                         break;
 486                     }
 487                 case NGM_ETHER_GET_AUTOSRC:
 488                         NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_WAITOK | M_NULLOK);
 489                         if (resp == NULL) {
 490                                 error = ENOMEM;
 491                                 break;
 492                         }
 493                         *((u_int32_t *)resp->data) = priv->autoSrcAddr;
 494                         break;
 495                 case NGM_ETHER_SET_AUTOSRC:
 496                         if (msg->header.arglen != sizeof(u_int32_t)) {
 497                                 error = EINVAL;
 498                                 break;
 499                         }
 500                         priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
 501                         break;
 502                 case NGM_ETHER_ADD_MULTI:
 503                     {
 504                         struct sockaddr_dl sa_dl;
 505                         struct ifmultiaddr *ifma;
 506
 507                         if (msg->header.arglen != ETHER_ADDR_LEN) {
 508                                 error = EINVAL;
 509                                 break;
 510                         }
 511                         bzero(&sa_dl, sizeof(struct sockaddr_dl));
 512                         sa_dl.sdl_len = sizeof(struct sockaddr_dl);
 513                         sa_dl.sdl_family = AF_LINK;
 514                         sa_dl.sdl_alen = ETHER_ADDR_LEN;
 515                         bcopy((void *)msg->data, LLADDR(&sa_dl),
 516                             ETHER_ADDR_LEN);
 517                         /*
 518                          * Netgraph is only permitted to join groups once
 519                          * via the if_addmulti() KPI, because it cannot hold
 520                          * struct ifmultiaddr * between calls. It may also
 521                          * lose a race while we check if the membership
 522                          * already exists.
 523                          */
 524                         IF_ADDR_LOCK(priv->ifp);
 525                         ifma = if_findmulti(priv->ifp,
 526                             (struct sockaddr *)&sa_dl);
 527                         IF_ADDR_UNLOCK(priv->ifp);
 528                         if (ifma != NULL) {
 529                                 error = EADDRINUSE;
 530                         } else {
 531                                 error = if_addmulti(priv->ifp,
 532                                     (struct sockaddr *)&sa_dl, &ifma);
 533                         }
 534                         break;
 535                     }
 536                 case NGM_ETHER_DEL_MULTI:
 537                     {
 538                         struct sockaddr_dl sa_dl;
 539
 540                         if (msg->header.arglen != ETHER_ADDR_LEN) {
 541                                 error = EINVAL;
 542                                 break;
 543                         }
 544                         bzero(&sa_dl, sizeof(struct sockaddr_dl));
 545                         sa_dl.sdl_len = sizeof(struct sockaddr_dl);
 546                         sa_dl.sdl_family = AF_LINK;
 547                         sa_dl.sdl_alen = ETHER_ADDR_LEN;
 548                         bcopy((void *)msg->data, LLADDR(&sa_dl),
 549                             ETHER_ADDR_LEN);
 550                         error = if_delmulti(priv->ifp,
 551                             (struct sockaddr *)&sa_dl);
 552                         break;
 553                     }
 554                 case NGM_ETHER_DETACH:
 555                         ng_ether_detach(priv->ifp);
 556                         break;
 557                 default:
 558                         error = EINVAL;
 559                         break;
 560                 }
 561                 break;
 562         default:
 563                 error = EINVAL;
 564                 break;
 565         }
 566         NG_RESPOND_MSG(error, node, item, resp);
 567         NG_FREE_MSG(msg);
 568         return (error);
 569 }
 570
 571 /*
 572  * Receive data on a hook.
 573  */
 574 static int
 575 ng_ether_rcvdata(hook_p hook, item_p item)
 576 {
 577         const node_p node = NG_HOOK_NODE(hook);
 578         const priv_p priv = NG_NODE_PRIVATE(node);
 579         struct mbuf *m;
 580
 581         NGI_GET_M(item, m);
 582         NG_FREE_ITEM(item);
 583
 584         if (hook == priv->lower || hook == priv->orphan)
 585                 return ng_ether_rcv_lower(node, m);
 586         if (hook == priv->upper)
 587                 return ng_ether_rcv_upper(node, m);
 588         panic("%s: weird hook", __func__);
 589 #ifdef RESTARTABLE_PANICS /* so we don't get an error msg in LINT */
 590         return (0);
 591 #endif
 592 }
 593
 594 /*
 595  * Handle an mbuf received on the "lower" or "orphan" hook.
 596  */
 597 static int
 598 ng_ether_rcv_lower(node_p node, struct mbuf *m)
 599 {
 600         const priv_p priv = NG_NODE_PRIVATE(node);
 601         struct ifnet *const ifp = priv->ifp;
 602
 603         /* Check whether interface is ready for packets */
 604         if (!((ifp->if_flags & IFF_UP) &&
 605             (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
 606                 NG_FREE_M(m);
 607                 return (ENETDOWN);
 608         }
 609
 610         /* Make sure header is fully pulled up */
 611         if (m->m_pkthdr.len < sizeof(struct ether_header)) {
 612                 NG_FREE_M(m);
 613                 return (EINVAL);
 614         }
 615         if (m->m_len < sizeof(struct ether_header)
 616             && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
 617                 return (ENOBUFS);
 618
 619         /* Drop in the MAC address if desired */
 620         if (priv->autoSrcAddr) {
 621
 622                 /* Make the mbuf writable if it's not already */
 623                 if (!M_WRITABLE(m)
 624                     && (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
 625                         return (ENOBUFS);
 626
 627                 /* Overwrite source MAC address */
 628                 bcopy(IF_LLADDR(ifp),
 629                     mtod(m, struct ether_header *)->ether_shost,
 630                     ETHER_ADDR_LEN);
 631         }
 632
 633         /* Send it on its way */
 634         return ether_output_frame(ifp, m);
 635 }
 636
 637 /*
 638  * Handle an mbuf received on the "upper" hook.
 639  */
 640 static int
 641 ng_ether_rcv_upper(node_p node, struct mbuf *m)
 642 {
 643         const priv_p priv = NG_NODE_PRIVATE(node);
 644         struct ifnet *ifp = priv->ifp;
 645
 646         /* Check length and pull off header */
 647         if (m->m_pkthdr.len < sizeof(struct ether_header)) {
 648                 NG_FREE_M(m);
 649                 return (EINVAL);
 650         }
 651         if (m->m_len < sizeof(struct ether_header) &&
 652             (m = m_pullup(m, sizeof(struct ether_header))) == NULL)
 653                 return (ENOBUFS);
 654
 655         m->m_pkthdr.rcvif = ifp;
 656
 657         /* Pass the packet to the bridge, it may come back to us */
 658         if (ifp->if_bridge) {
 659                 BRIDGE_INPUT(ifp, m);
 660                 if (m == NULL)
 661                         return (0);
 662         }
 663
 664         /* Route packet back in */
 665         ether_demux(ifp, m);
 666         return (0);
 667 }
 668
 669 /*
 670  * Shutdown node. This resets the node but does not remove it
 671  * unless the REALLY_DIE flag is set.
 672  */
 673 static int
 674 ng_ether_shutdown(node_p node)
 675 {
 676         const priv_p priv = NG_NODE_PRIVATE(node);
 677
 678         if (node->nd_flags & NGF_REALLY_DIE) {
 679                 /*
 680                  * WE came here because the ethernet card is being unloaded,
 681                  * so stop being persistant.
 682                  * Actually undo all the things we did on creation.
 683                  * Assume the ifp has already been freed.
 684                  */
 685                 NG_NODE_SET_PRIVATE(node, NULL);
 686                 FREE(priv, M_NETGRAPH);
 687                 NG_NODE_UNREF(node);    /* free node itself */
 688                 return (0);
 689         }
 690         if (priv->promisc) {            /* disable promiscuous mode */
 691                 (void)ifpromisc(priv->ifp, 0);
 692                 priv->promisc = 0;
 693         }
 694         priv->autoSrcAddr = 1;          /* reset auto-src-addr flag */
 695         NG_NODE_REVIVE(node);           /* Signal ng_rmnode we are persisant */
 696
 697         return (0);
 698 }
 699
 700 /*
 701  * Hook disconnection.
 702  */
 703 static int
 704 ng_ether_disconnect(hook_p hook)
 705 {
 706         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 707
 708         if (hook == priv->upper) {
 709                 priv->upper = NULL;
 710                 if (priv->ifp != NULL)          /* restore h/w csum */
 711                         priv->ifp->if_hwassist = priv->hwassist;
 712         } else if (hook == priv->lower)
 713                 priv->lower = NULL;
 714         else if (hook == priv->orphan)
 715                 priv->orphan = NULL;
 716         else
 717                 panic("%s: weird hook", __func__);
 718         if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
 719         && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
 720                 ng_rmnode_self(NG_HOOK_NODE(hook));     /* reset node */
 721         return (0);
 722 }
 723
 724 /******************************************************************
 725                         INITIALIZATION
 726 ******************************************************************/
 727
 728 /*
 729  * Handle loading and unloading for this node type.
 730  */
 731 static int
 732 ng_ether_mod_event(module_t mod, int event, void *data)
 733 {
 734         struct ifnet *ifp;
 735         int error = 0;
 736         int s;
 737
 738         s = splnet();
 739         switch (event) {
 740         case MOD_LOAD:
 741
 742                 /* Register function hooks */
 743                 if (ng_ether_attach_p != NULL) {
 744                         error = EEXIST;
 745                         break;
 746                 }
 747                 ng_ether_attach_p = ng_ether_attach;
 748                 ng_ether_detach_p = ng_ether_detach;
 749                 ng_ether_output_p = ng_ether_output;
 750                 ng_ether_input_p = ng_ether_input;
 751                 ng_ether_input_orphan_p = ng_ether_input_orphan;
 752                 ng_ether_link_state_p = ng_ether_link_state;
 753
 754                 /* Create nodes for any already-existing Ethernet interfaces */
 755                 IFNET_RLOCK();
 756                 TAILQ_FOREACH(ifp, &ifnet, if_link) {
 757                         if (ifp->if_type == IFT_ETHER
 758                             || ifp->if_type == IFT_L2VLAN)
 759                                 ng_ether_attach(ifp);
 760                 }
 761                 IFNET_RUNLOCK();
 762                 break;
 763
 764         case MOD_UNLOAD:
 765
 766                 /*
 767                  * Note that the base code won't try to unload us until
 768                  * all nodes have been removed, and that can't happen
 769                  * until all Ethernet interfaces are removed. In any
 770                  * case, we know there are no nodes left if the action
 771                  * is MOD_UNLOAD, so there's no need to detach any nodes.
 772                  */
 773
 774                 /* Unregister function hooks */
 775                 ng_ether_attach_p = NULL;
 776                 ng_ether_detach_p = NULL;
 777                 ng_ether_output_p = NULL;
 778                 ng_ether_input_p = NULL;
 779                 ng_ether_input_orphan_p = NULL;
 780                 ng_ether_link_state_p = NULL;
 781                 break;
 782
 783         default:
 784                 error = EOPNOTSUPP;
 785                 break;
 786         }
 787         splx(s);
 788         return (error);
 789 }
 790