sys/netgraph/ng_cisco.c

   1 /*
   2  * ng_cisco.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: Julian Elischer <julian@freebsd.org>
  39  *
  40  * $FreeBSD$
  41  * $Whistle: ng_cisco.c,v 1.25 1999/11/01 09:24:51 julian Exp $
  42  */
  43
  44 #include <sys/param.h>
  45 #include <sys/systm.h>
  46 #include <sys/errno.h>
  47 #include <sys/kernel.h>
  48 #include <sys/socket.h>
  49 #include <sys/malloc.h>
  50 #include <sys/mbuf.h>
  51 #include <sys/syslog.h>
  52
  53 #include <net/if.h>
  54
  55 #include <netinet/in.h>
  56 #include <netinet/if_ether.h>
  57
  58 #include <netgraph/ng_message.h>
  59 #include <netgraph/netgraph.h>
  60 #include <netgraph/ng_parse.h>
  61 #include <netgraph/ng_cisco.h>
  62
  63 #define CISCO_MULTICAST         0x8f    /* Cisco multicast address */
  64 #define CISCO_UNICAST           0x0f    /* Cisco unicast address */
  65 #define CISCO_KEEPALIVE         0x8035  /* Cisco keepalive protocol */
  66 #define CISCO_ADDR_REQ          0       /* Cisco address request */
  67 #define CISCO_ADDR_REPLY        1       /* Cisco address reply */
  68 #define CISCO_KEEPALIVE_REQ     2       /* Cisco keepalive request */
  69
  70 #define KEEPALIVE_SECS          10
  71
  72 struct cisco_header {
  73         uint8_t  address;
  74         uint8_t  control;
  75         uint16_t protocol;
  76 } __packed;
  77
  78 #define CISCO_HEADER_LEN        sizeof (struct cisco_header)
  79
  80 struct cisco_packet {
  81         uint32_t type;
  82         uint32_t par1;
  83         uint32_t par2;
  84         uint16_t rel;
  85         uint16_t time0;
  86         uint16_t time1;
  87 } __packed;
  88
  89 #define CISCO_PACKET_LEN (sizeof(struct cisco_packet))
  90
  91 struct protoent {
  92         hook_p  hook;           /* the hook for this proto */
  93         uint16_t af;            /* address family, -1 = downstream */
  94 };
  95
  96 struct cisco_priv {
  97         uint32_t local_seq;
  98         uint32_t remote_seq;
  99         uint32_t seqRetries;    /* how many times we've been here throwing out
 100                                  * the same sequence number without ack */
 101         node_p  node;
 102         struct callout handle;
 103         struct protoent downstream;
 104         struct protoent inet;           /* IP information */
 105         struct in_addr localip;
 106         struct in_addr localmask;
 107         struct protoent inet6;          /* IPv6 information */
 108         struct protoent atalk;          /* AppleTalk information */
 109         struct protoent ipx;            /* IPX information */
 110 };
 111 typedef struct cisco_priv *sc_p;
 112
 113 /* Netgraph methods */
 114 static ng_constructor_t         cisco_constructor;
 115 static ng_rcvmsg_t              cisco_rcvmsg;
 116 static ng_shutdown_t            cisco_shutdown;
 117 static ng_newhook_t             cisco_newhook;
 118 static ng_rcvdata_t             cisco_rcvdata;
 119 static ng_disconnect_t          cisco_disconnect;
 120
 121 /* Other functions */
 122 static int      cisco_input(sc_p sc, item_p item);
 123 static void     cisco_keepalive(node_p node, hook_p hook, void *arg1, int arg2);
 124 static int      cisco_send(sc_p sc, int type, long par1, long par2);
 125 static void     cisco_notify(sc_p sc, uint32_t cmd);
 126
 127 /* Parse type for struct ng_cisco_ipaddr */
 128 static const struct ng_parse_struct_field ng_cisco_ipaddr_type_fields[]
 129         = NG_CISCO_IPADDR_TYPE_INFO;
 130 static const struct ng_parse_type ng_cisco_ipaddr_type = {
 131         &ng_parse_struct_type,
 132         &ng_cisco_ipaddr_type_fields
 133 };
 134
 135 /* Parse type for struct ng_async_stat */
 136 static const struct ng_parse_struct_field ng_cisco_stats_type_fields[]
 137         = NG_CISCO_STATS_TYPE_INFO;
 138 static const struct ng_parse_type ng_cisco_stats_type = {
 139         &ng_parse_struct_type,
 140         &ng_cisco_stats_type_fields
 141 };
 142
 143 /* List of commands and how to convert arguments to/from ASCII */
 144 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
 145         {
 146           NGM_CISCO_COOKIE,
 147           NGM_CISCO_SET_IPADDR,
 148           "setipaddr",
 149           &ng_cisco_ipaddr_type,
 150           NULL
 151         },
 152         {
 153           NGM_CISCO_COOKIE,
 154           NGM_CISCO_GET_IPADDR,
 155           "getipaddr",
 156           NULL,
 157           &ng_cisco_ipaddr_type
 158         },
 159         {
 160           NGM_CISCO_COOKIE,
 161           NGM_CISCO_GET_STATUS,
 162           "getstats",
 163           NULL,
 164           &ng_cisco_stats_type
 165         },
 166         { 0 }
 167 };
 168
 169 /* Node type */
 170 static struct ng_type typestruct = {
 171         .version =      NG_ABI_VERSION,
 172         .name =         NG_CISCO_NODE_TYPE,
 173         .constructor =  cisco_constructor,
 174         .rcvmsg =       cisco_rcvmsg,
 175         .shutdown =     cisco_shutdown,
 176         .newhook =      cisco_newhook,
 177         .rcvdata =      cisco_rcvdata,
 178         .disconnect =   cisco_disconnect,
 179         .cmdlist =      ng_cisco_cmdlist,
 180 };
 181 NETGRAPH_INIT(cisco, &typestruct);
 182
 183 /*
 184  * Node constructor
 185  */
 186 static int
 187 cisco_constructor(node_p node)
 188 {
 189         sc_p sc;
 190
 191         sc = malloc(sizeof(*sc), M_NETGRAPH, M_WAITOK | M_ZERO);
 192
 193         ng_callout_init(&sc->handle);
 194         NG_NODE_SET_PRIVATE(node, sc);
 195         sc->node = node;
 196
 197         /* Initialise the varous protocol hook holders */
 198         sc->downstream.af = 0xffff;
 199         sc->inet.af = AF_INET;
 200         sc->inet6.af = AF_INET6;
 201         sc->atalk.af = AF_APPLETALK;
 202         sc->ipx.af = AF_IPX;
 203         return (0);
 204 }
 205
 206 /*
 207  * Check new hook
 208  */
 209 static int
 210 cisco_newhook(node_p node, hook_p hook, const char *name)
 211 {
 212         const sc_p sc = NG_NODE_PRIVATE(node);
 213
 214         if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
 215                 sc->downstream.hook = hook;
 216                 NG_HOOK_SET_PRIVATE(hook, &sc->downstream);
 217
 218                 /* Start keepalives */
 219                 ng_callout(&sc->handle, node, NULL, (hz * KEEPALIVE_SECS),
 220                     &cisco_keepalive, (void *)sc, 0);
 221         } else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
 222                 sc->inet.hook = hook;
 223                 NG_HOOK_SET_PRIVATE(hook, &sc->inet);
 224         } else if (strcmp(name, NG_CISCO_HOOK_INET6) == 0) {
 225                 sc->inet6.hook = hook;
 226                 NG_HOOK_SET_PRIVATE(hook, &sc->inet6);
 227         } else if (strcmp(name, NG_CISCO_HOOK_APPLETALK) == 0) {
 228                 sc->atalk.hook = hook;
 229                 NG_HOOK_SET_PRIVATE(hook, &sc->atalk);
 230         } else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
 231                 sc->ipx.hook = hook;
 232                 NG_HOOK_SET_PRIVATE(hook, &sc->ipx);
 233         } else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
 234                 NG_HOOK_SET_PRIVATE(hook, NULL);        /* unimplemented */
 235         } else
 236                 return (EINVAL);
 237         return 0;
 238 }
 239
 240 /*
 241  * Receive control message.
 242  */
 243 static int
 244 cisco_rcvmsg(node_p node, item_p item, hook_p lasthook)
 245 {
 246         struct ng_mesg *msg;
 247         const sc_p sc = NG_NODE_PRIVATE(node);
 248         struct ng_mesg *resp = NULL;
 249         int error = 0;
 250
 251         NGI_GET_MSG(item, msg);
 252         switch (msg->header.typecookie) {
 253         case NGM_GENERIC_COOKIE:
 254                 switch (msg->header.cmd) {
 255                 case NGM_TEXT_STATUS:
 256                     {
 257                         char *arg;
 258                         int pos;
 259
 260                         NG_MKRESPONSE(resp, msg, NG_TEXTRESPONSE, M_NOWAIT);
 261                         if (resp == NULL) {
 262                                 error = ENOMEM;
 263                                 break;
 264                         }
 265                         arg = (char *) resp->data;
 266                         pos = sprintf(arg,
 267                           "keepalive period: %d sec; ", KEEPALIVE_SECS);
 268                         pos += sprintf(arg + pos,
 269                           "unacknowledged keepalives: %d", sc->seqRetries);
 270                         resp->header.arglen = pos + 1;
 271                         break;
 272                     }
 273                 default:
 274                         error = EINVAL;
 275                         break;
 276                 }
 277                 break;
 278         case NGM_CISCO_COOKIE:
 279                 switch (msg->header.cmd) {
 280                 case NGM_CISCO_GET_IPADDR:      /* could be a late reply! */
 281                         if ((msg->header.flags & NGF_RESP) == 0) {
 282                                 struct in_addr *ips;
 283
 284                                 NG_MKRESPONSE(resp, msg,
 285                                     2 * sizeof(*ips), M_NOWAIT);
 286                                 if (!resp) {
 287                                         error = ENOMEM;
 288                                         break;
 289                                 }
 290                                 ips = (struct in_addr *) resp->data;
 291                                 ips[0] = sc->localip;
 292                                 ips[1] = sc->localmask;
 293                                 break;
 294                         }
 295                         /* FALLTHROUGH */       /* ...if it's a reply */
 296                 case NGM_CISCO_SET_IPADDR:
 297                     {
 298                         struct in_addr *const ips = (struct in_addr *)msg->data;
 299
 300                         if (msg->header.arglen < 2 * sizeof(*ips)) {
 301                                 error = EINVAL;
 302                                 break;
 303                         }
 304                         sc->localip = ips[0];
 305                         sc->localmask = ips[1];
 306                         break;
 307                     }
 308                 case NGM_CISCO_GET_STATUS:
 309                     {
 310                         struct ng_cisco_stats *stat;
 311
 312                         NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
 313                         if (!resp) {
 314                                 error = ENOMEM;
 315                                 break;
 316                         }
 317                         stat = (struct ng_cisco_stats *)resp->data;
 318                         stat->seqRetries = sc->seqRetries;
 319                         stat->keepAlivePeriod = KEEPALIVE_SECS;
 320                         break;
 321                     }
 322                 default:
 323                         error = EINVAL;
 324                         break;
 325                 }
 326                 break;
 327         default:
 328                 error = EINVAL;
 329                 break;
 330         }
 331         NG_RESPOND_MSG(error, node, item, resp);
 332         NG_FREE_MSG(msg);
 333         return (error);
 334 }
 335
 336 /*
 337  * Receive data
 338  */
 339 static int
 340 cisco_rcvdata(hook_p hook, item_p item)
 341 {
 342         const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 343         struct protoent *pep;
 344         struct cisco_header *h;
 345         struct mbuf *m;
 346         int error = 0;
 347
 348         if ((pep = NG_HOOK_PRIVATE(hook)) == NULL)
 349                 goto out;
 350
 351         /* If it came from our downlink, deal with it separately */
 352         if (pep->af == 0xffff)
 353                 return (cisco_input(sc, item));
 354
 355         /* OK so it came from a protocol, heading out. Prepend general data
 356            packet header. For now, IP,IPX only  */
 357         NGI_GET_M(item, m);
 358         M_PREPEND(m, CISCO_HEADER_LEN, M_NOWAIT);
 359         if (!m) {
 360                 error = ENOBUFS;
 361                 goto out;
 362         }
 363         NGI_M(item) = m;
 364         h = mtod(m, struct cisco_header *);
 365         h->address = CISCO_UNICAST;
 366         h->control = 0;
 367
 368         switch (pep->af) {
 369         case AF_INET:           /* Internet Protocol */
 370                 h->protocol = htons(ETHERTYPE_IP);
 371                 break;
 372         case AF_INET6:
 373                 h->protocol = htons(ETHERTYPE_IPV6);
 374                 break;
 375         case AF_APPLETALK:      /* AppleTalk Protocol */
 376                 h->protocol = htons(ETHERTYPE_AT);
 377                 break;
 378         case AF_IPX:            /* Novell IPX Protocol */
 379                 h->protocol = htons(ETHERTYPE_IPX);
 380                 break;
 381         default:
 382                 error = EAFNOSUPPORT;
 383                 goto out;
 384         }
 385
 386         /* Send it */
 387         NG_FWD_NEW_DATA(error, item,  sc->downstream.hook, m);
 388         return (error);
 389
 390 out:
 391         NG_FREE_ITEM(item);
 392         return (error);
 393 }
 394
 395 /*
 396  * Shutdown node
 397  */
 398 static int
 399 cisco_shutdown(node_p node)
 400 {
 401         const sc_p sc = NG_NODE_PRIVATE(node);
 402
 403         NG_NODE_SET_PRIVATE(node, NULL);
 404         NG_NODE_UNREF(sc->node);
 405         free(sc, M_NETGRAPH);
 406         return (0);
 407 }
 408
 409 /*
 410  * Disconnection of a hook
 411  *
 412  * For this type, removal of the last link destroys the node
 413  */
 414 static int
 415 cisco_disconnect(hook_p hook)
 416 {
 417         const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 418         struct protoent *pep;
 419
 420         /* Check it's not the debug hook */
 421         if ((pep = NG_HOOK_PRIVATE(hook))) {
 422                 pep->hook = NULL;
 423                 if (pep->af == 0xffff)
 424                         /* If it is the downstream hook, stop the timers */
 425                         ng_uncallout(&sc->handle, NG_HOOK_NODE(hook));
 426         }
 427
 428         /* If no more hooks, remove the node */
 429         if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
 430         && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
 431                 ng_rmnode_self(NG_HOOK_NODE(hook));
 432         return (0);
 433 }
 434
 435 /*
 436  * Receive data
 437  */
 438 static int
 439 cisco_input(sc_p sc, item_p item)
 440 {
 441         const struct cisco_header *h;
 442         struct cisco_header hdrbuf;
 443         struct protoent *pep;
 444         struct mbuf *m;
 445         int error = 0;
 446
 447         /* Get data */
 448         m = NGI_M(item);
 449
 450         /* Sanity check header length */
 451         if (m->m_pkthdr.len < sizeof(*h)) {
 452                 error = EINVAL;
 453                 goto drop;
 454         }
 455
 456         /* Get cisco header */
 457         if (m->m_len >= sizeof(*h))                     /* the common case */
 458                 h = mtod(m, const struct cisco_header *);
 459         else {
 460                 m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
 461                 h = &hdrbuf;
 462         }
 463         m_adj(m, sizeof(*h));
 464
 465         /* Check header address */
 466         switch (h->address) {
 467         default:                /* Invalid Cisco packet. */
 468                 goto drop;
 469         case CISCO_UNICAST:
 470         case CISCO_MULTICAST:
 471                 /* Don't check the control field here (RFC 1547). */
 472                 switch (ntohs(h->protocol)) {
 473                 default:
 474                         goto drop;
 475                 case CISCO_KEEPALIVE:
 476                     {
 477                         const struct cisco_packet *p;
 478                         struct cisco_packet pktbuf;
 479
 480                         /* Sanity check packet length */
 481                         if (m->m_pkthdr.len < sizeof(*p)) {
 482                                 error = EINVAL;
 483                                 goto drop;
 484                         }
 485
 486                         /* Get cisco packet */
 487                         if (m->m_len >= sizeof(*p))     /* the common case */
 488                                 p = mtod(m, const struct cisco_packet *);
 489                         else {
 490                                 m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
 491                                 p = &pktbuf;
 492                         }
 493
 494                         /* Check packet type */
 495                         switch (ntohl(p->type)) {
 496                         default:
 497                                 log(LOG_WARNING,
 498                                     "cisco: unknown cisco packet type: 0x%lx\n",
 499                                        (long)ntohl(p->type));
 500                                 break;
 501                         case CISCO_ADDR_REPLY:
 502                                 /* Reply on address request, ignore */
 503                                 break;
 504                         case CISCO_KEEPALIVE_REQ:
 505                                 sc->remote_seq = ntohl(p->par1);
 506                                 if (sc->local_seq == ntohl(p->par2)) {
 507                                         sc->local_seq++;
 508                                         if (sc->seqRetries > 1)
 509                                                 cisco_notify(sc, NGM_LINK_IS_UP);
 510                                         sc->seqRetries = 0;
 511                                 }
 512                                 break;
 513                         case CISCO_ADDR_REQ:
 514                             {
 515                                 struct ng_mesg *msg;
 516                                 int dummy_error = 0;
 517
 518                                 /* Ask inet peer for IP address information */
 519                                 if (sc->inet.hook == NULL)
 520                                         goto nomsg;
 521                                 NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
 522                                     NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
 523                                 if (msg == NULL)
 524                                         goto nomsg;
 525                                 NG_SEND_MSG_HOOK(dummy_error,
 526                                     sc->node, msg, sc->inet.hook, 0);
 527                 /*
 528                  * XXX Now maybe we should set a flag telling
 529                  * our receiver to send this message when the response comes in
 530                  * instead of now when the data may be bad.
 531                  */
 532                 nomsg:
 533                                 /* Send reply to peer device */
 534                                 error = cisco_send(sc, CISCO_ADDR_REPLY,
 535                                             ntohl(sc->localip.s_addr),
 536                                             ntohl(sc->localmask.s_addr));
 537                                 break;
 538                             }
 539                         }
 540                         goto drop;
 541                     }
 542                 case ETHERTYPE_IP:
 543                         pep = &sc->inet;
 544                         break;
 545                 case ETHERTYPE_IPV6:
 546                         pep = &sc->inet6;
 547                         break;
 548                 case ETHERTYPE_AT:
 549                         pep = &sc->atalk;
 550                         break;
 551                 case ETHERTYPE_IPX:
 552                         pep = &sc->ipx;
 553                         break;
 554                 }
 555                 break;
 556         }
 557
 558         /* Drop if payload is empty */
 559         if (m->m_pkthdr.len == 0) {
 560                 error = EINVAL;
 561                 goto drop;
 562         }
 563
 564         /* Send it on */
 565         if (pep->hook == NULL)
 566                 goto drop;
 567         NG_FWD_NEW_DATA(error, item, pep->hook, m);
 568         return (error);
 569
 570 drop:
 571         NG_FREE_ITEM(item);
 572         return (error);
 573 }
 574
 575
 576 /*
 577  * Send keepalive packets, every 10 seconds.
 578  */
 579 static void
 580 cisco_keepalive(node_p node, hook_p hook, void *arg1, int arg2)
 581 {
 582         const sc_p sc = arg1;
 583
 584         cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
 585         if (sc->seqRetries++ > 1)
 586                 cisco_notify(sc, NGM_LINK_IS_DOWN);
 587         ng_callout(&sc->handle, node, NULL, (hz * KEEPALIVE_SECS),
 588             &cisco_keepalive, (void *)sc, 0);
 589 }
 590
 591 /*
 592  * Send Cisco keepalive packet.
 593  */
 594 static int
 595 cisco_send(sc_p sc, int type, long par1, long par2)
 596 {
 597         struct cisco_header *h;
 598         struct cisco_packet *ch;
 599         struct mbuf *m;
 600         struct timeval time;
 601         uint32_t t;
 602         int     error = 0;
 603
 604         getmicrouptime(&time);
 605
 606         MGETHDR(m, M_NOWAIT, MT_DATA);
 607         if (!m)
 608                 return (ENOBUFS);
 609
 610         t = time.tv_sec * 1000 + time.tv_usec / 1000;
 611         m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
 612         m->m_pkthdr.rcvif = 0;
 613
 614         h = mtod(m, struct cisco_header *);
 615         h->address = CISCO_MULTICAST;
 616         h->control = 0;
 617         h->protocol = htons(CISCO_KEEPALIVE);
 618
 619         ch = (struct cisco_packet *) (h + 1);
 620         ch->type = htonl(type);
 621         ch->par1 = htonl(par1);
 622         ch->par2 = htonl(par2);
 623         ch->rel = -1;
 624         ch->time0 = htons((uint16_t) (t >> 16));
 625         ch->time1 = htons((uint16_t) t);
 626
 627         NG_SEND_DATA_ONLY(error, sc->downstream.hook, m);
 628         return (error);
 629 }
 630
 631 /*
 632  * Send linkstate to upstream node.
 633  */
 634 static void
 635 cisco_notify(sc_p sc, uint32_t cmd)
 636 {
 637         struct ng_mesg *msg;
 638         int dummy_error = 0;
 639
 640         if (sc->inet.hook == NULL) /* nothing to notify */
 641                 return;
 642
 643         NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
 644         if (msg != NULL)
 645                 NG_SEND_MSG_HOOK(dummy_error, sc->node, msg, sc->inet.hook, 0);
 646 }