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