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  * $DragonFly: src/sys/netgraph/cisco/ng_cisco.c,v 1.3 2003/08/07 21:17:31 dillon Exp $
  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 <netatalk/at.h>
  59
  60 #include <netipx/ipx.h>
  61 #include <netipx/ipx_if.h>
  62
  63 #include <netgraph/ng_message.h>
  64 #include <netgraph/netgraph.h>
  65 #include <netgraph/ng_parse.h>
  66 #include "ng_cisco.h"
  67
  68 #define CISCO_MULTICAST         0x8f    /* Cisco multicast address */
  69 #define CISCO_UNICAST           0x0f    /* Cisco unicast address */
  70 #define CISCO_KEEPALIVE         0x8035  /* Cisco keepalive protocol */
  71 #define CISCO_ADDR_REQ          0       /* Cisco address request */
  72 #define CISCO_ADDR_REPLY        1       /* Cisco address reply */
  73 #define CISCO_KEEPALIVE_REQ     2       /* Cisco keepalive request */
  74
  75 #define KEEPALIVE_SECS          10
  76
  77 struct cisco_header {
  78         u_char  address;
  79         u_char  control;
  80         u_short protocol;
  81 };
  82
  83 #define CISCO_HEADER_LEN          sizeof (struct cisco_header)
  84
  85 struct cisco_packet {
  86         u_long  type;
  87         u_long  par1;
  88         u_long  par2;
  89         u_short rel;
  90         u_short time0;
  91         u_short time1;
  92 };
  93
  94 #define CISCO_PACKET_LEN (sizeof(struct cisco_packet))
  95
  96 struct protoent {
  97         hook_p  hook;           /* the hook for this proto */
  98         u_short af;             /* address family, -1 = downstream */
  99 };
 100
 101 struct cisco_priv {
 102         u_long  local_seq;
 103         u_long  remote_seq;
 104         u_long  seqRetries;     /* how many times we've been here throwing out
 105                                  * the same sequence number without ack */
 106         node_p  node;
 107         struct callout_handle handle;
 108         struct protoent downstream;
 109         struct protoent inet;           /* IP information */
 110         struct in_addr localip;
 111         struct in_addr localmask;
 112         struct protoent inet6;          /* IPv6 information */
 113         struct protoent atalk;          /* AppleTalk information */
 114         struct protoent ipx;            /* IPX information */
 115 };
 116 typedef struct cisco_priv *sc_p;
 117
 118 /* Netgraph methods */
 119 static ng_constructor_t         cisco_constructor;
 120 static ng_rcvmsg_t              cisco_rcvmsg;
 121 static ng_shutdown_t            cisco_rmnode;
 122 static ng_newhook_t             cisco_newhook;
 123 static ng_rcvdata_t             cisco_rcvdata;
 124 static ng_disconnect_t          cisco_disconnect;
 125
 126 /* Other functions */
 127 static int      cisco_input(sc_p sc, struct mbuf *m, meta_p meta);
 128 static void     cisco_keepalive(void *arg);
 129 static int      cisco_send(sc_p sc, int type, long par1, long par2);
 130
 131 /* Parse type for struct ng_cisco_ipaddr */
 132 static const struct ng_parse_struct_field ng_cisco_ipaddr_type_fields[]
 133         = NG_CISCO_IPADDR_TYPE_INFO;
 134 static const struct ng_parse_type ng_cisco_ipaddr_type = {
 135         &ng_parse_struct_type,
 136         &ng_cisco_ipaddr_type_fields
 137 };
 138
 139 /* Parse type for struct ng_async_stat */
 140 static const struct ng_parse_struct_field ng_cisco_stats_type_fields[]
 141         = NG_CISCO_STATS_TYPE_INFO;
 142 static const struct ng_parse_type ng_cisco_stats_type = {
 143         &ng_parse_struct_type,
 144         &ng_cisco_stats_type_fields
 145 };
 146
 147 /* List of commands and how to convert arguments to/from ASCII */
 148 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
 149         {
 150           NGM_CISCO_COOKIE,
 151           NGM_CISCO_SET_IPADDR,
 152           "setipaddr",
 153           &ng_cisco_ipaddr_type,
 154           NULL
 155         },
 156         {
 157           NGM_CISCO_COOKIE,
 158           NGM_CISCO_GET_IPADDR,
 159           "getipaddr",
 160           NULL,
 161           &ng_cisco_ipaddr_type
 162         },
 163         {
 164           NGM_CISCO_COOKIE,
 165           NGM_CISCO_GET_STATUS,
 166           "getstats",
 167           NULL,
 168           &ng_cisco_stats_type
 169         },
 170         { 0 }
 171 };
 172
 173 /* Node type */
 174 static struct ng_type typestruct = {
 175         NG_VERSION,
 176         NG_CISCO_NODE_TYPE,
 177         NULL,
 178         cisco_constructor,
 179         cisco_rcvmsg,
 180         cisco_rmnode,
 181         cisco_newhook,
 182         NULL,
 183         NULL,
 184         cisco_rcvdata,
 185         cisco_rcvdata,
 186         cisco_disconnect,
 187         ng_cisco_cmdlist
 188 };
 189 NETGRAPH_INIT(cisco, &typestruct);
 190
 191 /*
 192  * Node constructor
 193  */
 194 static int
 195 cisco_constructor(node_p *nodep)
 196 {
 197         sc_p sc;
 198         int error = 0;
 199
 200         MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT);
 201         if (sc == NULL)
 202                 return (ENOMEM);
 203         bzero(sc, sizeof(struct cisco_priv));
 204
 205         callout_handle_init(&sc->handle);
 206         if ((error = ng_make_node_common(&typestruct, nodep))) {
 207                 FREE(sc, M_NETGRAPH);
 208                 return (error);
 209         }
 210         (*nodep)->private = sc;
 211         sc->node = *nodep;
 212
 213         /* Initialise the varous protocol hook holders */
 214         sc->downstream.af = 0xffff;
 215         sc->inet.af = AF_INET;
 216         sc->inet6.af = AF_INET6;
 217         sc->atalk.af = AF_APPLETALK;
 218         sc->ipx.af = AF_IPX;
 219         return (0);
 220 }
 221
 222 /*
 223  * Check new hook
 224  */
 225 static int
 226 cisco_newhook(node_p node, hook_p hook, const char *name)
 227 {
 228         const sc_p sc = node->private;
 229
 230         if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
 231                 sc->downstream.hook = hook;
 232                 hook->private = &sc->downstream;
 233
 234                 /* Start keepalives */
 235                 sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
 236         } else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
 237                 sc->inet.hook = hook;
 238                 hook->private = &sc->inet;
 239         } else if (strcmp(name, NG_CISCO_HOOK_APPLETALK) == 0) {
 240                 sc->atalk.hook = hook;
 241                 hook->private = &sc->atalk;
 242         } else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
 243                 sc->ipx.hook = hook;
 244                 hook->private = &sc->ipx;
 245         } else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
 246                 hook->private = NULL;   /* unimplemented */
 247         } else
 248                 return (EINVAL);
 249         return 0;
 250 }
 251
 252 /*
 253  * Receive control message.
 254  */
 255 static int
 256 cisco_rcvmsg(node_p node, struct ng_mesg *msg,
 257         const char *retaddr, struct ng_mesg **rptr)
 258 {
 259         const sc_p sc = node->private;
 260         struct ng_mesg *resp = NULL;
 261         int error = 0;
 262
 263         switch (msg->header.typecookie) {
 264         case NGM_GENERIC_COOKIE:
 265                 switch (msg->header.cmd) {
 266                 case NGM_TEXT_STATUS:
 267                     {
 268                         char *arg;
 269                         int pos;
 270
 271                         NG_MKRESPONSE(resp, msg, sizeof(struct ng_mesg)
 272                             + NG_TEXTRESPONSE, M_NOWAIT);
 273                         if (resp == NULL) {
 274                                 error = ENOMEM;
 275                                 break;
 276                         }
 277                         arg = (char *) resp->data;
 278                         pos = sprintf(arg,
 279                           "keepalive period: %d sec; ", KEEPALIVE_SECS);
 280                         pos += sprintf(arg + pos,
 281                           "unacknowledged keepalives: %ld", sc->seqRetries);
 282                         resp->header.arglen = pos + 1;
 283                         break;
 284                     }
 285                 default:
 286                         error = EINVAL;
 287                         break;
 288                 }
 289                 break;
 290         case NGM_CISCO_COOKIE:
 291                 switch (msg->header.cmd) {
 292                 case NGM_CISCO_GET_IPADDR:      /* could be a late reply! */
 293                         if ((msg->header.flags & NGF_RESP) == 0) {
 294                                 struct in_addr *ips;
 295
 296                                 NG_MKRESPONSE(resp, msg,
 297                                     2 * sizeof(*ips), M_NOWAIT);
 298                                 if (!resp) {
 299                                         error = ENOMEM;
 300                                         break;
 301                                 }
 302                                 ips = (struct in_addr *) resp->data;
 303                                 ips[0] = sc->localip;
 304                                 ips[1] = sc->localmask;
 305                                 break;
 306                         }
 307                         /* FALLTHROUGH */       /* ...if it's a reply */
 308                 case NGM_CISCO_SET_IPADDR:
 309                     {
 310                         struct in_addr *const ips = (struct in_addr *)msg->data;
 311
 312                         if (msg->header.arglen < 2 * sizeof(*ips)) {
 313                                 error = EINVAL;
 314                                 break;
 315                         }
 316                         sc->localip = ips[0];
 317                         sc->localmask = ips[1];
 318                         break;
 319                     }
 320                 case NGM_CISCO_GET_STATUS:
 321                     {
 322                         struct ng_cisco_stats *stat;
 323
 324                         NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
 325                         if (!resp) {
 326                                 error = ENOMEM;
 327                                 break;
 328                         }
 329                         stat = (struct ng_cisco_stats *)resp->data;
 330                         stat->seqRetries = sc->seqRetries;
 331                         stat->keepAlivePeriod = KEEPALIVE_SECS;
 332                         break;
 333                     }
 334                 default:
 335                         error = EINVAL;
 336                         break;
 337                 }
 338                 break;
 339         default:
 340                 error = EINVAL;
 341                 break;
 342         }
 343         if (rptr)
 344                 *rptr = resp;
 345         else if (resp)
 346                 FREE(resp, M_NETGRAPH);
 347         FREE(msg, M_NETGRAPH);
 348         return (error);
 349 }
 350
 351 /*
 352  * Receive data
 353  */
 354 static int
 355 cisco_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
 356 {
 357         const sc_p sc = hook->node->private;
 358         struct protoent *pep;
 359         struct cisco_header *h;
 360         int error = 0;
 361
 362         if ((pep = hook->private) == NULL)
 363                 goto out;
 364
 365         /* If it came from our downlink, deal with it separately */
 366         if (pep->af == 0xffff)
 367                 return (cisco_input(sc, m, meta));
 368
 369         /* OK so it came from a protocol, heading out. Prepend general data
 370            packet header. For now, IP,IPX only  */
 371         M_PREPEND(m, CISCO_HEADER_LEN, M_DONTWAIT);
 372         if (!m) {
 373                 error = ENOBUFS;
 374                 goto out;
 375         }
 376         h = mtod(m, struct cisco_header *);
 377         h->address = CISCO_UNICAST;
 378         h->control = 0;
 379
 380         switch (pep->af) {
 381         case AF_INET:           /* Internet Protocol */
 382                 h->protocol = htons(ETHERTYPE_IP);
 383                 break;
 384         case AF_INET6:
 385                 h->protocol = htons(ETHERTYPE_IPV6);
 386                 break;
 387         case AF_APPLETALK:      /* AppleTalk Protocol */
 388                 h->protocol = htons(ETHERTYPE_AT);
 389                 break;
 390         case AF_IPX:            /* Novell IPX Protocol */
 391                 h->protocol = htons(ETHERTYPE_IPX);
 392                 break;
 393         default:
 394                 error = EAFNOSUPPORT;
 395                 goto out;
 396         }
 397
 398         /* Send it */
 399         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 400         return (error);
 401
 402 out:
 403         NG_FREE_DATA(m, meta);
 404         return (error);
 405 }
 406
 407 /*
 408  * Shutdown node
 409  */
 410 static int
 411 cisco_rmnode(node_p node)
 412 {
 413         const sc_p sc = node->private;
 414
 415         node->flags |= NG_INVALID;
 416         ng_cutlinks(node);
 417         ng_unname(node);
 418         node->private = NULL;
 419         ng_unref(sc->node);
 420         FREE(sc, M_NETGRAPH);
 421         return (0);
 422 }
 423
 424 /*
 425  * Disconnection of a hook
 426  *
 427  * For this type, removal of the last link destroys the node
 428  */
 429 static int
 430 cisco_disconnect(hook_p hook)
 431 {
 432         const sc_p sc = hook->node->private;
 433         struct protoent *pep;
 434
 435         /* Check it's not the debug hook */
 436         if ((pep = hook->private)) {
 437                 pep->hook = NULL;
 438                 if (pep->af == 0xffff) {
 439                         /* If it is the downstream hook, stop the timers */
 440                         untimeout(cisco_keepalive, sc, sc->handle);
 441                 }
 442         }
 443
 444         /* If no more hooks, remove the node */
 445         if (hook->node->numhooks == 0)
 446                 ng_rmnode(hook->node);
 447         return (0);
 448 }
 449
 450 /*
 451  * Receive data
 452  */
 453 static int
 454 cisco_input(sc_p sc, struct mbuf *m, meta_p meta)
 455 {
 456         const struct cisco_header *h;
 457         struct cisco_header hdrbuf;
 458         struct protoent *pep;
 459         int error = 0;
 460
 461         /* Sanity check header length */
 462         if (m->m_pkthdr.len < sizeof(*h)) {
 463                 error = EINVAL;
 464                 goto drop;
 465         }
 466
 467         /* Get cisco header */
 468         if (m->m_len >= sizeof(*h))                     /* the common case */
 469                 h = mtod(m, const struct cisco_header *);
 470         else {
 471                 m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
 472                 h = &hdrbuf;
 473         }
 474         m_adj(m, sizeof(*h));
 475
 476         /* Check header address */
 477         switch (h->address) {
 478         default:                /* Invalid Cisco packet. */
 479                 goto drop;
 480         case CISCO_UNICAST:
 481         case CISCO_MULTICAST:
 482                 /* Don't check the control field here (RFC 1547). */
 483                 switch (ntohs(h->protocol)) {
 484                 default:
 485                         goto drop;
 486                 case CISCO_KEEPALIVE:
 487                     {
 488                         const struct cisco_packet *p;
 489                         struct cisco_packet pktbuf;
 490
 491                         /* Sanity check packet length */
 492                         if (m->m_pkthdr.len < sizeof(*p)) {
 493                                 error = EINVAL;
 494                                 goto drop;
 495                         }
 496
 497                         /* Get cisco packet */
 498                         if (m->m_len >= sizeof(*p))     /* the common case */
 499                                 p = mtod(m, const struct cisco_packet *);
 500                         else {
 501                                 m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
 502                                 p = &pktbuf;
 503                         }
 504
 505                         /* Check packet type */
 506                         switch (ntohl(p->type)) {
 507                         default:
 508                                 log(LOG_WARNING,
 509                                     "cisco: unknown cisco packet type: 0x%lx\n",
 510                                        ntohl(p->type));
 511                                 break;
 512                         case CISCO_ADDR_REPLY:
 513                                 /* Reply on address request, ignore */
 514                                 break;
 515                         case CISCO_KEEPALIVE_REQ:
 516                                 sc->remote_seq = ntohl(p->par1);
 517                                 if (sc->local_seq == ntohl(p->par2)) {
 518                                         sc->local_seq++;
 519                                         sc->seqRetries = 0;
 520                                 }
 521                                 break;
 522                         case CISCO_ADDR_REQ:
 523                             {
 524                                 struct ng_mesg *msg, *resp;
 525
 526                                 /* Ask inet peer for IP address information */
 527                                 if (sc->inet.hook == NULL)
 528                                         goto nomsg;
 529                                 NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
 530                                     NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
 531                                 if (msg == NULL)
 532                                         goto nomsg;
 533                                 ng_send_msg(sc->node, msg,
 534                                     NG_CISCO_HOOK_INET, &resp);
 535                                 if (resp != NULL)
 536                                         cisco_rcvmsg(sc->node, resp, ".", NULL);
 537
 538                 nomsg:
 539                                 /* Send reply to peer device */
 540                                 error = cisco_send(sc, CISCO_ADDR_REPLY,
 541                                             ntohl(sc->localip.s_addr),
 542                                             ntohl(sc->localmask.s_addr));
 543                                 break;
 544                             }
 545                         }
 546                         goto drop;
 547                     }
 548                 case ETHERTYPE_IP:
 549                         pep = &sc->inet;
 550                         break;
 551                 case ETHERTYPE_IPV6:
 552                         pep = &sc->inet6;
 553                         break;
 554                 case ETHERTYPE_AT:
 555                         pep = &sc->atalk;
 556                         break;
 557                 case ETHERTYPE_IPX:
 558                         pep = &sc->ipx;
 559                         break;
 560                 }
 561                 break;
 562         }
 563
 564         /* Drop if payload is empty */
 565         if (m->m_pkthdr.len == 0) {
 566                 error = EINVAL;
 567                 goto drop;
 568         }
 569
 570         /* Send it on */
 571         if (pep->hook == NULL)
 572                 goto drop;
 573         NG_SEND_DATA(error, pep->hook, m, meta);
 574         return (error);
 575
 576 drop:
 577         NG_FREE_DATA(m, meta);
 578         return (error);
 579 }
 580
 581
 582 /*
 583  * Send keepalive packets, every 10 seconds.
 584  */
 585 static void
 586 cisco_keepalive(void *arg)
 587 {
 588         const sc_p sc = arg;
 589         int s = splimp();
 590
 591         cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
 592         sc->seqRetries++;
 593         splx(s);
 594         sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
 595 }
 596
 597 /*
 598  * Send Cisco keepalive packet.
 599  */
 600 static int
 601 cisco_send(sc_p sc, int type, long par1, long par2)
 602 {
 603         struct cisco_header *h;
 604         struct cisco_packet *ch;
 605         struct mbuf *m;
 606         u_long  t;
 607         int     error = 0;
 608         meta_p  meta = NULL;
 609         struct timeval time;
 610
 611         getmicrotime(&time);
 612
 613         MGETHDR(m, M_DONTWAIT, MT_DATA);
 614         if (!m)
 615                 return (ENOBUFS);
 616
 617         t = (time.tv_sec - boottime.tv_sec) * 1000;
 618         m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
 619         m->m_pkthdr.rcvif = 0;
 620
 621         h = mtod(m, struct cisco_header *);
 622         h->address = CISCO_MULTICAST;
 623         h->control = 0;
 624         h->protocol = htons(CISCO_KEEPALIVE);
 625
 626         ch = (struct cisco_packet *) (h + 1);
 627         ch->type = htonl(type);
 628         ch->par1 = htonl(par1);
 629         ch->par2 = htonl(par2);
 630         ch->rel = -1;
 631         ch->time0 = htons((u_short) (t >> 16));
 632         ch->time1 = htons((u_short) t);
 633
 634         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 635         return (error);
 636 }