sys/netgraph/cisco/ng_cisco.c

   1
   2 /*
   3  * ng_cisco.c
   4  *
   5  * Copyright (c) 1996-1999 Whistle Communications, Inc.
   6  * All rights reserved.
   7  *
   8  * Subject to the following obligations and disclaimer of warranty, use and
   9  * redistribution of this software, in source or object code forms, with or
  10  * without modifications are expressly permitted by Whistle Communications;
  11  * provided, however, that:
  12  * 1. Any and all reproductions of the source or object code must include the
  13  *    copyright notice above and the following disclaimer of warranties; and
  14  * 2. No rights are granted, in any manner or form, to use Whistle
  15  *    Communications, Inc. trademarks, including the mark "WHISTLE
  16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
  17  *    such appears in the above copyright notice or in the software.
  18  *
  19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
  20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
  21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
  22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
  23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
  24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
  25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
  26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
  27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
  28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
  29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
  31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
  32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
  35  * OF SUCH DAMAGE.
  36  *
  37  * Author: Julian Elischer <julian@freebsd.org>
  38  *
  39  * $FreeBSD: src/sys/netgraph/ng_cisco.c,v 1.4.2.6 2002/07/02 23:44:02 archie Exp $
  40  * $Whistle: ng_cisco.c,v 1.25 1999/11/01 09:24:51 julian Exp $
  41  */
  42
  43 #include <sys/param.h>
  44 #include <sys/systm.h>
  45 #include <sys/errno.h>
  46 #include <sys/kernel.h>
  47 #include <sys/socket.h>
  48 #include <sys/malloc.h>
  49 #include <sys/mbuf.h>
  50 #include <sys/syslog.h>
  51
  52 #include <net/if.h>
  53
  54 #include <netinet/in.h>
  55 #include <netinet/if_ether.h>
  56
  57 #include <netatalk/at.h>
  58
  59 #include <netipx/ipx.h>
  60 #include <netipx/ipx_if.h>
  61
  62 #include <netgraph/ng_message.h>
  63 #include <netgraph/netgraph.h>
  64 #include <netgraph/ng_parse.h>
  65 #include <netgraph/ng_cisco.h>
  66
  67 #define CISCO_MULTICAST         0x8f    /* Cisco multicast address */
  68 #define CISCO_UNICAST           0x0f    /* Cisco unicast address */
  69 #define CISCO_KEEPALIVE         0x8035  /* Cisco keepalive protocol */
  70 #define CISCO_ADDR_REQ          0       /* Cisco address request */
  71 #define CISCO_ADDR_REPLY        1       /* Cisco address reply */
  72 #define CISCO_KEEPALIVE_REQ     2       /* Cisco keepalive request */
  73
  74 #define KEEPALIVE_SECS          10
  75
  76 struct cisco_header {
  77         u_char  address;
  78         u_char  control;
  79         u_short protocol;
  80 };
  81
  82 #define CISCO_HEADER_LEN          sizeof (struct cisco_header)
  83
  84 struct cisco_packet {
  85         u_long  type;
  86         u_long  par1;
  87         u_long  par2;
  88         u_short rel;
  89         u_short time0;
  90         u_short time1;
  91 };
  92
  93 #define CISCO_PACKET_LEN (sizeof(struct cisco_packet))
  94
  95 struct protoent {
  96         hook_p  hook;           /* the hook for this proto */
  97         u_short af;             /* address family, -1 = downstream */
  98 };
  99
 100 struct cisco_priv {
 101         u_long  local_seq;
 102         u_long  remote_seq;
 103         u_long  seqRetries;     /* how many times we've been here throwing out
 104                                  * the same sequence number without ack */
 105         node_p  node;
 106         struct callout_handle handle;
 107         struct protoent downstream;
 108         struct protoent inet;           /* IP information */
 109         struct in_addr localip;
 110         struct in_addr localmask;
 111         struct protoent inet6;          /* IPv6 information */
 112         struct protoent atalk;          /* AppleTalk information */
 113         struct protoent ipx;            /* IPX information */
 114 };
 115 typedef struct cisco_priv *sc_p;
 116
 117 /* Netgraph methods */
 118 static ng_constructor_t         cisco_constructor;
 119 static ng_rcvmsg_t              cisco_rcvmsg;
 120 static ng_shutdown_t            cisco_rmnode;
 121 static ng_newhook_t             cisco_newhook;
 122 static ng_rcvdata_t             cisco_rcvdata;
 123 static ng_disconnect_t          cisco_disconnect;
 124
 125 /* Other functions */
 126 static int      cisco_input(sc_p sc, struct mbuf *m, meta_p meta);
 127 static void     cisco_keepalive(void *arg);
 128 static int      cisco_send(sc_p sc, int type, long par1, long par2);
 129
 130 /* Parse type for struct ng_cisco_ipaddr */
 131 static const struct ng_parse_struct_field ng_cisco_ipaddr_type_fields[]
 132         = NG_CISCO_IPADDR_TYPE_INFO;
 133 static const struct ng_parse_type ng_cisco_ipaddr_type = {
 134         &ng_parse_struct_type,
 135         &ng_cisco_ipaddr_type_fields
 136 };
 137
 138 /* Parse type for struct ng_async_stat */
 139 static const struct ng_parse_struct_field ng_cisco_stats_type_fields[]
 140         = NG_CISCO_STATS_TYPE_INFO;
 141 static const struct ng_parse_type ng_cisco_stats_type = {
 142         &ng_parse_struct_type,
 143         &ng_cisco_stats_type_fields
 144 };
 145
 146 /* List of commands and how to convert arguments to/from ASCII */
 147 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
 148         {
 149           NGM_CISCO_COOKIE,
 150           NGM_CISCO_SET_IPADDR,
 151           "setipaddr",
 152           &ng_cisco_ipaddr_type,
 153           NULL
 154         },
 155         {
 156           NGM_CISCO_COOKIE,
 157           NGM_CISCO_GET_IPADDR,
 158           "getipaddr",
 159           NULL,
 160           &ng_cisco_ipaddr_type
 161         },
 162         {
 163           NGM_CISCO_COOKIE,
 164           NGM_CISCO_GET_STATUS,
 165           "getstats",
 166           NULL,
 167           &ng_cisco_stats_type
 168         },
 169         { 0 }
 170 };
 171
 172 /* Node type */
 173 static struct ng_type typestruct = {
 174         NG_VERSION,
 175         NG_CISCO_NODE_TYPE,
 176         NULL,
 177         cisco_constructor,
 178         cisco_rcvmsg,
 179         cisco_rmnode,
 180         cisco_newhook,
 181         NULL,
 182         NULL,
 183         cisco_rcvdata,
 184         cisco_rcvdata,
 185         cisco_disconnect,
 186         ng_cisco_cmdlist
 187 };
 188 NETGRAPH_INIT(cisco, &typestruct);
 189
 190 /*
 191  * Node constructor
 192  */
 193 static int
 194 cisco_constructor(node_p *nodep)
 195 {
 196         sc_p sc;
 197         int error = 0;
 198
 199         MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT);
 200         if (sc == NULL)
 201                 return (ENOMEM);
 202         bzero(sc, sizeof(struct cisco_priv));
 203
 204         callout_handle_init(&sc->handle);
 205         if ((error = ng_make_node_common(&typestruct, nodep))) {
 206                 FREE(sc, M_NETGRAPH);
 207                 return (error);
 208         }
 209         (*nodep)->private = sc;
 210         sc->node = *nodep;
 211
 212         /* Initialise the varous protocol hook holders */
 213         sc->downstream.af = 0xffff;
 214         sc->inet.af = AF_INET;
 215         sc->inet6.af = AF_INET6;
 216         sc->atalk.af = AF_APPLETALK;
 217         sc->ipx.af = AF_IPX;
 218         return (0);
 219 }
 220
 221 /*
 222  * Check new hook
 223  */
 224 static int
 225 cisco_newhook(node_p node, hook_p hook, const char *name)
 226 {
 227         const sc_p sc = node->private;
 228
 229         if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
 230                 sc->downstream.hook = hook;
 231                 hook->private = &sc->downstream;
 232
 233                 /* Start keepalives */
 234                 sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
 235         } else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
 236                 sc->inet.hook = hook;
 237                 hook->private = &sc->inet;
 238         } else if (strcmp(name, NG_CISCO_HOOK_APPLETALK) == 0) {
 239                 sc->atalk.hook = hook;
 240                 hook->private = &sc->atalk;
 241         } else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
 242                 sc->ipx.hook = hook;
 243                 hook->private = &sc->ipx;
 244         } else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
 245                 hook->private = NULL;   /* unimplemented */
 246         } else
 247                 return (EINVAL);
 248         return 0;
 249 }
 250
 251 /*
 252  * Receive control message.
 253  */
 254 static int
 255 cisco_rcvmsg(node_p node, struct ng_mesg *msg,
 256         const char *retaddr, struct ng_mesg **rptr)
 257 {
 258         const sc_p sc = node->private;
 259         struct ng_mesg *resp = NULL;
 260         int error = 0;
 261
 262         switch (msg->header.typecookie) {
 263         case NGM_GENERIC_COOKIE:
 264                 switch (msg->header.cmd) {
 265                 case NGM_TEXT_STATUS:
 266                     {
 267                         char *arg;
 268                         int pos;
 269
 270                         NG_MKRESPONSE(resp, msg, sizeof(struct ng_mesg)
 271                             + NG_TEXTRESPONSE, M_NOWAIT);
 272                         if (resp == NULL) {
 273                                 error = ENOMEM;
 274                                 break;
 275                         }
 276                         arg = (char *) resp->data;
 277                         pos = sprintf(arg,
 278                           "keepalive period: %d sec; ", KEEPALIVE_SECS);
 279                         pos += sprintf(arg + pos,
 280                           "unacknowledged keepalives: %ld", sc->seqRetries);
 281                         resp->header.arglen = pos + 1;
 282                         break;
 283                     }
 284                 default:
 285                         error = EINVAL;
 286                         break;
 287                 }
 288                 break;
 289         case NGM_CISCO_COOKIE:
 290                 switch (msg->header.cmd) {
 291                 case NGM_CISCO_GET_IPADDR:      /* could be a late reply! */
 292                         if ((msg->header.flags & NGF_RESP) == 0) {
 293                                 struct in_addr *ips;
 294
 295                                 NG_MKRESPONSE(resp, msg,
 296                                     2 * sizeof(*ips), M_NOWAIT);
 297                                 if (!resp) {
 298                                         error = ENOMEM;
 299                                         break;
 300                                 }
 301                                 ips = (struct in_addr *) resp->data;
 302                                 ips[0] = sc->localip;
 303                                 ips[1] = sc->localmask;
 304                                 break;
 305                         }
 306                         /* FALLTHROUGH */       /* ...if it's a reply */
 307                 case NGM_CISCO_SET_IPADDR:
 308                     {
 309                         struct in_addr *const ips = (struct in_addr *)msg->data;
 310
 311                         if (msg->header.arglen < 2 * sizeof(*ips)) {
 312                                 error = EINVAL;
 313                                 break;
 314                         }
 315                         sc->localip = ips[0];
 316                         sc->localmask = ips[1];
 317                         break;
 318                     }
 319                 case NGM_CISCO_GET_STATUS:
 320                     {
 321                         struct ng_cisco_stats *stat;
 322
 323                         NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
 324                         if (!resp) {
 325                                 error = ENOMEM;
 326                                 break;
 327                         }
 328                         stat = (struct ng_cisco_stats *)resp->data;
 329                         stat->seqRetries = sc->seqRetries;
 330                         stat->keepAlivePeriod = KEEPALIVE_SECS;
 331                         break;
 332                     }
 333                 default:
 334                         error = EINVAL;
 335                         break;
 336                 }
 337                 break;
 338         default:
 339                 error = EINVAL;
 340                 break;
 341         }
 342         if (rptr)
 343                 *rptr = resp;
 344         else if (resp)
 345                 FREE(resp, M_NETGRAPH);
 346         FREE(msg, M_NETGRAPH);
 347         return (error);
 348 }
 349
 350 /*
 351  * Receive data
 352  */
 353 static int
 354 cisco_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
 355 {
 356         const sc_p sc = hook->node->private;
 357         struct protoent *pep;
 358         struct cisco_header *h;
 359         int error = 0;
 360
 361         if ((pep = hook->private) == NULL)
 362                 goto out;
 363
 364         /* If it came from our downlink, deal with it separately */
 365         if (pep->af == 0xffff)
 366                 return (cisco_input(sc, m, meta));
 367
 368         /* OK so it came from a protocol, heading out. Prepend general data
 369            packet header. For now, IP,IPX only  */
 370         M_PREPEND(m, CISCO_HEADER_LEN, M_DONTWAIT);
 371         if (!m) {
 372                 error = ENOBUFS;
 373                 goto out;
 374         }
 375         h = mtod(m, struct cisco_header *);
 376         h->address = CISCO_UNICAST;
 377         h->control = 0;
 378
 379         switch (pep->af) {
 380         case AF_INET:           /* Internet Protocol */
 381                 h->protocol = htons(ETHERTYPE_IP);
 382                 break;
 383         case AF_INET6:
 384                 h->protocol = htons(ETHERTYPE_IPV6);
 385                 break;
 386         case AF_APPLETALK:      /* AppleTalk Protocol */
 387                 h->protocol = htons(ETHERTYPE_AT);
 388                 break;
 389         case AF_IPX:            /* Novell IPX Protocol */
 390                 h->protocol = htons(ETHERTYPE_IPX);
 391                 break;
 392         default:
 393                 error = EAFNOSUPPORT;
 394                 goto out;
 395         }
 396
 397         /* Send it */
 398         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 399         return (error);
 400
 401 out:
 402         NG_FREE_DATA(m, meta);
 403         return (error);
 404 }
 405
 406 /*
 407  * Shutdown node
 408  */
 409 static int
 410 cisco_rmnode(node_p node)
 411 {
 412         const sc_p sc = node->private;
 413
 414         node->flags |= NG_INVALID;
 415         ng_cutlinks(node);
 416         ng_unname(node);
 417         node->private = NULL;
 418         ng_unref(sc->node);
 419         FREE(sc, M_NETGRAPH);
 420         return (0);
 421 }
 422
 423 /*
 424  * Disconnection of a hook
 425  *
 426  * For this type, removal of the last link destroys the node
 427  */
 428 static int
 429 cisco_disconnect(hook_p hook)
 430 {
 431         const sc_p sc = hook->node->private;
 432         struct protoent *pep;
 433
 434         /* Check it's not the debug hook */
 435         if ((pep = hook->private)) {
 436                 pep->hook = NULL;
 437                 if (pep->af == 0xffff) {
 438                         /* If it is the downstream hook, stop the timers */
 439                         untimeout(cisco_keepalive, sc, sc->handle);
 440                 }
 441         }
 442
 443         /* If no more hooks, remove the node */
 444         if (hook->node->numhooks == 0)
 445                 ng_rmnode(hook->node);
 446         return (0);
 447 }
 448
 449 /*
 450  * Receive data
 451  */
 452 static int
 453 cisco_input(sc_p sc, struct mbuf *m, meta_p meta)
 454 {
 455         const struct cisco_header *h;
 456         struct cisco_header hdrbuf;
 457         struct protoent *pep;
 458         int error = 0;
 459
 460         /* Sanity check header length */
 461         if (m->m_pkthdr.len < sizeof(*h)) {
 462                 error = EINVAL;
 463                 goto drop;
 464         }
 465
 466         /* Get cisco header */
 467         if (m->m_len >= sizeof(*h))                     /* the common case */
 468                 h = mtod(m, const struct cisco_header *);
 469         else {
 470                 m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
 471                 h = &hdrbuf;
 472         }
 473         m_adj(m, sizeof(*h));
 474
 475         /* Check header address */
 476         switch (h->address) {
 477         default:                /* Invalid Cisco packet. */
 478                 goto drop;
 479         case CISCO_UNICAST:
 480         case CISCO_MULTICAST:
 481                 /* Don't check the control field here (RFC 1547). */
 482                 switch (ntohs(h->protocol)) {
 483                 default:
 484                         goto drop;
 485                 case CISCO_KEEPALIVE:
 486                     {
 487                         const struct cisco_packet *p;
 488                         struct cisco_packet pktbuf;
 489
 490                         /* Sanity check packet length */
 491                         if (m->m_pkthdr.len < sizeof(*p)) {
 492                                 error = EINVAL;
 493                                 goto drop;
 494                         }
 495
 496                         /* Get cisco packet */
 497                         if (m->m_len >= sizeof(*p))     /* the common case */
 498                                 p = mtod(m, const struct cisco_packet *);
 499                         else {
 500                                 m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
 501                                 p = &pktbuf;
 502                         }
 503
 504                         /* Check packet type */
 505                         switch (ntohl(p->type)) {
 506                         default:
 507                                 log(LOG_WARNING,
 508                                     "cisco: unknown cisco packet type: 0x%lx\n",
 509                                        ntohl(p->type));
 510                                 break;
 511                         case CISCO_ADDR_REPLY:
 512                                 /* Reply on address request, ignore */
 513                                 break;
 514                         case CISCO_KEEPALIVE_REQ:
 515                                 sc->remote_seq = ntohl(p->par1);
 516                                 if (sc->local_seq == ntohl(p->par2)) {
 517                                         sc->local_seq++;
 518                                         sc->seqRetries = 0;
 519                                 }
 520                                 break;
 521                         case CISCO_ADDR_REQ:
 522                             {
 523                                 struct ng_mesg *msg, *resp;
 524
 525                                 /* Ask inet peer for IP address information */
 526                                 if (sc->inet.hook == NULL)
 527                                         goto nomsg;
 528                                 NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
 529                                     NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
 530                                 if (msg == NULL)
 531                                         goto nomsg;
 532                                 ng_send_msg(sc->node, msg,
 533                                     NG_CISCO_HOOK_INET, &resp);
 534                                 if (resp != NULL)
 535                                         cisco_rcvmsg(sc->node, resp, ".", NULL);
 536
 537                 nomsg:
 538                                 /* Send reply to peer device */
 539                                 error = cisco_send(sc, CISCO_ADDR_REPLY,
 540                                             ntohl(sc->localip.s_addr),
 541                                             ntohl(sc->localmask.s_addr));
 542                                 break;
 543                             }
 544                         }
 545                         goto drop;
 546                     }
 547                 case ETHERTYPE_IP:
 548                         pep = &sc->inet;
 549                         break;
 550                 case ETHERTYPE_IPV6:
 551                         pep = &sc->inet6;
 552                         break;
 553                 case ETHERTYPE_AT:
 554                         pep = &sc->atalk;
 555                         break;
 556                 case ETHERTYPE_IPX:
 557                         pep = &sc->ipx;
 558                         break;
 559                 }
 560                 break;
 561         }
 562
 563         /* Drop if payload is empty */
 564         if (m->m_pkthdr.len == 0) {
 565                 error = EINVAL;
 566                 goto drop;
 567         }
 568
 569         /* Send it on */
 570         if (pep->hook == NULL)
 571                 goto drop;
 572         NG_SEND_DATA(error, pep->hook, m, meta);
 573         return (error);
 574
 575 drop:
 576         NG_FREE_DATA(m, meta);
 577         return (error);
 578 }
 579
 580
 581 /*
 582  * Send keepalive packets, every 10 seconds.
 583  */
 584 static void
 585 cisco_keepalive(void *arg)
 586 {
 587         const sc_p sc = arg;
 588         int s = splimp();
 589
 590         cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
 591         sc->seqRetries++;
 592         splx(s);
 593         sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
 594 }
 595
 596 /*
 597  * Send Cisco keepalive packet.
 598  */
 599 static int
 600 cisco_send(sc_p sc, int type, long par1, long par2)
 601 {
 602         struct cisco_header *h;
 603         struct cisco_packet *ch;
 604         struct mbuf *m;
 605         u_long  t;
 606         int     error = 0;
 607         meta_p  meta = NULL;
 608         struct timeval time;
 609
 610         getmicrotime(&time);
 611
 612         MGETHDR(m, M_DONTWAIT, MT_DATA);
 613         if (!m)
 614                 return (ENOBUFS);
 615
 616         t = (time.tv_sec - boottime.tv_sec) * 1000;
 617         m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
 618         m->m_pkthdr.rcvif = 0;
 619
 620         h = mtod(m, struct cisco_header *);
 621         h->address = CISCO_MULTICAST;
 622         h->control = 0;
 623         h->protocol = htons(CISCO_KEEPALIVE);
 624
 625         ch = (struct cisco_packet *) (h + 1);
 626         ch->type = htonl(type);
 627         ch->par1 = htonl(par1);
 628         ch->par2 = htonl(par2);
 629         ch->rel = -1;
 630         ch->time0 = htons((u_short) (t >> 16));
 631         ch->time1 = htons((u_short) t);
 632
 633         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 634         return (error);
 635 }