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 #include <sys/thread2.h>
  52
  53 #include <machine/inttypes.h>
  54
  55 #include <net/if.h>
  56
  57 #include <netinet/in.h>
  58 #include <netinet/if_ether.h>
  59
  60 #include <netproto/ipx/ipx.h>
  61 #include <netproto/ipx/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 timeout;
 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 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         sc = kmalloc(sizeof(*sc), M_NETGRAPH, M_NOWAIT | M_ZERO);
 200         if (sc == NULL)
 201                 return (ENOMEM);
 202
 203         callout_init(&sc->timeout);
 204         if ((error = ng_make_node_common(&typestruct, nodep))) {
 205                 kfree(sc, M_NETGRAPH);
 206                 return (error);
 207         }
 208         (*nodep)->private = sc;
 209         sc->node = *nodep;
 210
 211         /* Initialise the varous protocol hook holders */
 212         sc->downstream.af = 0xffff;
 213         sc->inet.af = AF_INET;
 214         sc->inet6.af = AF_INET6;
 215         sc->ipx.af = AF_IPX;
 216         return (0);
 217 }
 218
 219 /*
 220  * Check new hook
 221  */
 222 static int
 223 cisco_newhook(node_p node, hook_p hook, const char *name)
 224 {
 225         const sc_p sc = node->private;
 226
 227         if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
 228                 sc->downstream.hook = hook;
 229                 hook->private = &sc->downstream;
 230
 231                 /* Start keepalives */
 232                 callout_reset(&sc->timeout, hz * KEEPALIVE_SECS,
 233                                 cisco_keepalive, sc);
 234         } else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
 235                 sc->inet.hook = hook;
 236                 hook->private = &sc->inet;
 237         } else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
 238                 sc->ipx.hook = hook;
 239                 hook->private = &sc->ipx;
 240         } else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
 241                 hook->private = NULL;   /* unimplemented */
 242         } else
 243                 return (EINVAL);
 244         return 0;
 245 }
 246
 247 /*
 248  * Receive control message.
 249  */
 250 static int
 251 cisco_rcvmsg(node_p node, struct ng_mesg *msg,
 252         const char *retaddr, struct ng_mesg **rptr)
 253 {
 254         const sc_p sc = node->private;
 255         struct ng_mesg *resp = NULL;
 256         int error = 0;
 257
 258         switch (msg->header.typecookie) {
 259         case NGM_GENERIC_COOKIE:
 260                 switch (msg->header.cmd) {
 261                 case NGM_TEXT_STATUS:
 262                     {
 263                         char *arg;
 264                         int pos;
 265
 266                         NG_MKRESPONSE(resp, msg, sizeof(struct ng_mesg)
 267                             + NG_TEXTRESPONSE, M_NOWAIT);
 268                         if (resp == NULL) {
 269                                 error = ENOMEM;
 270                                 break;
 271                         }
 272                         arg = (char *) resp->data;
 273                         pos = ksprintf(arg,
 274                           "keepalive period: %d sec; ", KEEPALIVE_SECS);
 275                         pos += ksprintf(arg + pos,
 276                           "unacknowledged keepalives: %ld", sc->seqRetries);
 277                         resp->header.arglen = pos + 1;
 278                         break;
 279                     }
 280                 default:
 281                         error = EINVAL;
 282                         break;
 283                 }
 284                 break;
 285         case NGM_CISCO_COOKIE:
 286                 switch (msg->header.cmd) {
 287                 case NGM_CISCO_GET_IPADDR:      /* could be a late reply! */
 288                         if ((msg->header.flags & NGF_RESP) == 0) {
 289                                 struct in_addr *ips;
 290
 291                                 NG_MKRESPONSE(resp, msg,
 292                                     2 * sizeof(*ips), M_NOWAIT);
 293                                 if (!resp) {
 294                                         error = ENOMEM;
 295                                         break;
 296                                 }
 297                                 ips = (struct in_addr *) resp->data;
 298                                 ips[0] = sc->localip;
 299                                 ips[1] = sc->localmask;
 300                                 break;
 301                         }
 302                         /* FALLTHROUGH */       /* ...if it's a reply */
 303                 case NGM_CISCO_SET_IPADDR:
 304                     {
 305                         struct in_addr *const ips = (struct in_addr *)msg->data;
 306
 307                         if (msg->header.arglen < 2 * sizeof(*ips)) {
 308                                 error = EINVAL;
 309                                 break;
 310                         }
 311                         sc->localip = ips[0];
 312                         sc->localmask = ips[1];
 313                         break;
 314                     }
 315                 case NGM_CISCO_GET_STATUS:
 316                     {
 317                         struct ng_cisco_stats *stat;
 318
 319                         NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
 320                         if (!resp) {
 321                                 error = ENOMEM;
 322                                 break;
 323                         }
 324                         stat = (struct ng_cisco_stats *)resp->data;
 325                         stat->seqRetries = sc->seqRetries;
 326                         stat->keepAlivePeriod = KEEPALIVE_SECS;
 327                         break;
 328                     }
 329                 default:
 330                         error = EINVAL;
 331                         break;
 332                 }
 333                 break;
 334         default:
 335                 error = EINVAL;
 336                 break;
 337         }
 338         if (rptr)
 339                 *rptr = resp;
 340         else if (resp)
 341                 kfree(resp, M_NETGRAPH);
 342         kfree(msg, M_NETGRAPH);
 343         return (error);
 344 }
 345
 346 /*
 347  * Receive data
 348  */
 349 static int
 350 cisco_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
 351 {
 352         const sc_p sc = hook->node->private;
 353         struct protoent *pep;
 354         struct cisco_header *h;
 355         int error = 0;
 356
 357         if ((pep = hook->private) == NULL)
 358                 goto out;
 359
 360         /* If it came from our downlink, deal with it separately */
 361         if (pep->af == 0xffff)
 362                 return (cisco_input(sc, m, meta));
 363
 364         /* OK so it came from a protocol, heading out. Prepend general data
 365            packet header. For now, IP,IPX only  */
 366         M_PREPEND(m, CISCO_HEADER_LEN, MB_DONTWAIT);
 367         if (!m) {
 368                 error = ENOBUFS;
 369                 goto out;
 370         }
 371         h = mtod(m, struct cisco_header *);
 372         h->address = CISCO_UNICAST;
 373         h->control = 0;
 374
 375         switch (pep->af) {
 376         case AF_INET:           /* Internet Protocol */
 377                 h->protocol = htons(ETHERTYPE_IP);
 378                 break;
 379         case AF_INET6:
 380                 h->protocol = htons(ETHERTYPE_IPV6);
 381                 break;
 382         case AF_IPX:            /* Novell IPX Protocol */
 383                 h->protocol = htons(ETHERTYPE_IPX);
 384                 break;
 385         default:
 386                 error = EAFNOSUPPORT;
 387                 goto out;
 388         }
 389
 390         /* Send it */
 391         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 392         return (error);
 393
 394 out:
 395         NG_FREE_DATA(m, meta);
 396         return (error);
 397 }
 398
 399 /*
 400  * Shutdown node
 401  */
 402 static int
 403 cisco_rmnode(node_p node)
 404 {
 405         const sc_p sc = node->private;
 406
 407         node->flags |= NG_INVALID;
 408         ng_cutlinks(node);
 409         ng_unname(node);
 410         node->private = NULL;
 411         ng_unref(sc->node);
 412         kfree(sc, M_NETGRAPH);
 413         return (0);
 414 }
 415
 416 /*
 417  * Disconnection of a hook
 418  *
 419  * For this type, removal of the last link destroys the node
 420  */
 421 static int
 422 cisco_disconnect(hook_p hook)
 423 {
 424         const sc_p sc = hook->node->private;
 425         struct protoent *pep;
 426
 427         /* Check it's not the debug hook */
 428         if ((pep = hook->private)) {
 429                 pep->hook = NULL;
 430                 if (pep->af == 0xffff) {
 431                         /* If it is the downstream hook, stop the timers */
 432                         callout_stop(&sc->timeout);
 433                 }
 434         }
 435
 436         /* If no more hooks, remove the node */
 437         if (hook->node->numhooks == 0)
 438                 ng_rmnode(hook->node);
 439         return (0);
 440 }
 441
 442 /*
 443  * Receive data
 444  */
 445 static int
 446 cisco_input(sc_p sc, struct mbuf *m, meta_p meta)
 447 {
 448         const struct cisco_header *h;
 449         struct cisco_header hdrbuf;
 450         struct protoent *pep;
 451         int error = 0;
 452
 453         /* Sanity check header length */
 454         if (m->m_pkthdr.len < sizeof(*h)) {
 455                 error = EINVAL;
 456                 goto drop;
 457         }
 458
 459         /* Get cisco header */
 460         if (m->m_len >= sizeof(*h))                     /* the common case */
 461                 h = mtod(m, const struct cisco_header *);
 462         else {
 463                 m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
 464                 h = &hdrbuf;
 465         }
 466         m_adj(m, sizeof(*h));
 467
 468         /* Check header address */
 469         switch (h->address) {
 470         default:                /* Invalid Cisco packet. */
 471                 goto drop;
 472         case CISCO_UNICAST:
 473         case CISCO_MULTICAST:
 474                 /* Don't check the control field here (RFC 1547). */
 475                 switch (ntohs(h->protocol)) {
 476                 default:
 477                         goto drop;
 478                 case CISCO_KEEPALIVE:
 479                     {
 480                         const struct cisco_packet *p;
 481                         struct cisco_packet pktbuf;
 482
 483                         /* Sanity check packet length */
 484                         if (m->m_pkthdr.len < sizeof(*p)) {
 485                                 error = EINVAL;
 486                                 goto drop;
 487                         }
 488
 489                         /* Get cisco packet */
 490                         if (m->m_len >= sizeof(*p))     /* the common case */
 491                                 p = mtod(m, const struct cisco_packet *);
 492                         else {
 493                                 m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
 494                                 p = &pktbuf;
 495                         }
 496
 497                         /* Check packet type */
 498                         switch (ntohl(p->type)) {
 499                         default:
 500                                 log(LOG_WARNING,
 501                                     "cisco: unknown cisco packet type: 0x%"PRIx32"\n",
 502                                        ntohl(p->type));
 503                                 break;
 504                         case CISCO_ADDR_REPLY:
 505                                 /* Reply on address request, ignore */
 506                                 break;
 507                         case CISCO_KEEPALIVE_REQ:
 508                                 sc->remote_seq = ntohl(p->par1);
 509                                 if (sc->local_seq == ntohl(p->par2)) {
 510                                         sc->local_seq++;
 511                                         sc->seqRetries = 0;
 512                                 }
 513                                 break;
 514                         case CISCO_ADDR_REQ:
 515                             {
 516                                 struct ng_mesg *msg, *resp;
 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(sc->node, msg,
 526                                     NG_CISCO_HOOK_INET, &resp);
 527                                 if (resp != NULL)
 528                                         cisco_rcvmsg(sc->node, resp, ".", NULL);
 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_IPX:
 547                         pep = &sc->ipx;
 548                         break;
 549                 }
 550                 break;
 551         }
 552
 553         /* Drop if payload is empty */
 554         if (m->m_pkthdr.len == 0) {
 555                 error = EINVAL;
 556                 goto drop;
 557         }
 558
 559         /* Send it on */
 560         if (pep->hook == NULL)
 561                 goto drop;
 562         NG_SEND_DATA(error, pep->hook, m, meta);
 563         return (error);
 564
 565 drop:
 566         NG_FREE_DATA(m, meta);
 567         return (error);
 568 }
 569
 570
 571 /*
 572  * Send keepalive packets, every 10 seconds.
 573  */
 574 static void
 575 cisco_keepalive(void *arg)
 576 {
 577         const sc_p sc = arg;
 578
 579         crit_enter();
 580         cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
 581         sc->seqRetries++;
 582         crit_exit();
 583         callout_reset(&sc->timeout, hz * KEEPALIVE_SECS,
 584                         cisco_keepalive, sc);
 585 }
 586
 587 /*
 588  * Send Cisco keepalive packet.
 589  */
 590 static int
 591 cisco_send(sc_p sc, int type, long par1, long par2)
 592 {
 593         struct cisco_header *h;
 594         struct cisco_packet *ch;
 595         struct mbuf *m;
 596         u_long  t;
 597         int     error = 0;
 598         meta_p  meta = NULL;
 599         struct timeval time;
 600
 601         getmicrotime(&time);
 602
 603         MGETHDR(m, MB_DONTWAIT, MT_DATA);
 604         if (!m)
 605                 return (ENOBUFS);
 606
 607         t = (time.tv_sec - boottime.tv_sec) * 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((u_short) (t >> 16));
 622         ch->time1 = htons((u_short) t);
 623
 624         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 625         return (error);
 626 }