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 <netgraph/ng_message.h>
  61 #include <netgraph/netgraph.h>
  62 #include <netgraph/ng_parse.h>
  63 #include "ng_cisco.h"
  64
  65 #define CISCO_MULTICAST         0x8f    /* Cisco multicast address */
  66 #define CISCO_UNICAST           0x0f    /* Cisco unicast address */
  67 #define CISCO_KEEPALIVE         0x8035  /* Cisco keepalive protocol */
  68 #define CISCO_ADDR_REQ          0       /* Cisco address request */
  69 #define CISCO_ADDR_REPLY        1       /* Cisco address reply */
  70 #define CISCO_KEEPALIVE_REQ     2       /* Cisco keepalive request */
  71
  72 #define KEEPALIVE_SECS          10
  73
  74 struct cisco_header {
  75         u_char  address;
  76         u_char  control;
  77         u_short protocol;
  78 };
  79
  80 #define CISCO_HEADER_LEN          sizeof (struct cisco_header)
  81
  82 struct cisco_packet {
  83         u_long  type;
  84         u_long  par1;
  85         u_long  par2;
  86         u_short rel;
  87         u_short time0;
  88         u_short time1;
  89 };
  90
  91 #define CISCO_PACKET_LEN (sizeof(struct cisco_packet))
  92
  93 struct protoent {
  94         hook_p  hook;           /* the hook for this proto */
  95         u_short af;             /* address family, -1 = downstream */
  96 };
  97
  98 struct cisco_priv {
  99         u_long  local_seq;
 100         u_long  remote_seq;
 101         u_long  seqRetries;     /* how many times we've been here throwing out
 102                                  * the same sequence number without ack */
 103         node_p  node;
 104         struct callout timeout;
 105         struct protoent downstream;
 106         struct protoent inet;           /* IP information */
 107         struct in_addr localip;
 108         struct in_addr localmask;
 109         struct protoent inet6;          /* IPv6 information */
 110         struct protoent ipx;            /* IPX information */
 111 };
 112 typedef struct cisco_priv *sc_p;
 113
 114 /* Netgraph methods */
 115 static ng_constructor_t         cisco_constructor;
 116 static ng_rcvmsg_t              cisco_rcvmsg;
 117 static ng_shutdown_t            cisco_rmnode;
 118 static ng_newhook_t             cisco_newhook;
 119 static ng_rcvdata_t             cisco_rcvdata;
 120 static ng_disconnect_t          cisco_disconnect;
 121
 122 /* Other functions */
 123 static int      cisco_input(sc_p sc, struct mbuf *m, meta_p meta);
 124 static void     cisco_keepalive(void *arg);
 125 static int      cisco_send(sc_p sc, int type, long par1, long par2);
 126
 127 /* Parse type for struct ng_cisco_ipaddr */
 128 static const struct ng_parse_struct_field ng_cisco_ipaddr_type_fields[]
 129         = NG_CISCO_IPADDR_TYPE_INFO;
 130 static const struct ng_parse_type ng_cisco_ipaddr_type = {
 131         &ng_parse_struct_type,
 132         &ng_cisco_ipaddr_type_fields
 133 };
 134
 135 /* Parse type for struct ng_async_stat */
 136 static const struct ng_parse_struct_field ng_cisco_stats_type_fields[]
 137         = NG_CISCO_STATS_TYPE_INFO;
 138 static const struct ng_parse_type ng_cisco_stats_type = {
 139         &ng_parse_struct_type,
 140         &ng_cisco_stats_type_fields
 141 };
 142
 143 /* List of commands and how to convert arguments to/from ASCII */
 144 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
 145         {
 146           NGM_CISCO_COOKIE,
 147           NGM_CISCO_SET_IPADDR,
 148           "setipaddr",
 149           &ng_cisco_ipaddr_type,
 150           NULL
 151         },
 152         {
 153           NGM_CISCO_COOKIE,
 154           NGM_CISCO_GET_IPADDR,
 155           "getipaddr",
 156           NULL,
 157           &ng_cisco_ipaddr_type
 158         },
 159         {
 160           NGM_CISCO_COOKIE,
 161           NGM_CISCO_GET_STATUS,
 162           "getstats",
 163           NULL,
 164           &ng_cisco_stats_type
 165         },
 166         { 0 }
 167 };
 168
 169 /* Node type */
 170 static struct ng_type typestruct = {
 171         NG_VERSION,
 172         NG_CISCO_NODE_TYPE,
 173         NULL,
 174         cisco_constructor,
 175         cisco_rcvmsg,
 176         cisco_rmnode,
 177         cisco_newhook,
 178         NULL,
 179         NULL,
 180         cisco_rcvdata,
 181         cisco_rcvdata,
 182         cisco_disconnect,
 183         ng_cisco_cmdlist
 184 };
 185 NETGRAPH_INIT(cisco, &typestruct);
 186
 187 /*
 188  * Node constructor
 189  */
 190 static int
 191 cisco_constructor(node_p *nodep)
 192 {
 193         sc_p sc;
 194         int error = 0;
 195
 196         sc = kmalloc(sizeof(*sc), M_NETGRAPH, M_NOWAIT | M_ZERO);
 197         if (sc == NULL)
 198                 return (ENOMEM);
 199
 200         callout_init(&sc->timeout);
 201         if ((error = ng_make_node_common(&typestruct, nodep))) {
 202                 kfree(sc, M_NETGRAPH);
 203                 return (error);
 204         }
 205         (*nodep)->private = sc;
 206         sc->node = *nodep;
 207
 208         /* Initialise the varous protocol hook holders */
 209         sc->downstream.af = 0xffff;
 210         sc->inet.af = AF_INET;
 211         sc->inet6.af = AF_INET6;
 212         sc->ipx.af = AF_IPX;
 213         return (0);
 214 }
 215
 216 /*
 217  * Check new hook
 218  */
 219 static int
 220 cisco_newhook(node_p node, hook_p hook, const char *name)
 221 {
 222         const sc_p sc = node->private;
 223
 224         if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
 225                 sc->downstream.hook = hook;
 226                 hook->private = &sc->downstream;
 227
 228                 /* Start keepalives */
 229                 callout_reset(&sc->timeout, hz * KEEPALIVE_SECS,
 230                                 cisco_keepalive, sc);
 231         } else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
 232                 sc->inet.hook = hook;
 233                 hook->private = &sc->inet;
 234         } else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
 235                 sc->ipx.hook = hook;
 236                 hook->private = &sc->ipx;
 237         } else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
 238                 hook->private = NULL;   /* unimplemented */
 239         } else
 240                 return (EINVAL);
 241         return 0;
 242 }
 243
 244 /*
 245  * Receive control message.
 246  */
 247 static int
 248 cisco_rcvmsg(node_p node, struct ng_mesg *msg,
 249         const char *retaddr, struct ng_mesg **rptr)
 250 {
 251         const sc_p sc = node->private;
 252         struct ng_mesg *resp = NULL;
 253         int error = 0;
 254
 255         switch (msg->header.typecookie) {
 256         case NGM_GENERIC_COOKIE:
 257                 switch (msg->header.cmd) {
 258                 case NGM_TEXT_STATUS:
 259                     {
 260                         char *arg;
 261                         int pos;
 262
 263                         NG_MKRESPONSE(resp, msg, sizeof(struct ng_mesg)
 264                             + NG_TEXTRESPONSE, M_NOWAIT);
 265                         if (resp == NULL) {
 266                                 error = ENOMEM;
 267                                 break;
 268                         }
 269                         arg = (char *) resp->data;
 270                         pos = ksprintf(arg,
 271                           "keepalive period: %d sec; ", KEEPALIVE_SECS);
 272                         pos += ksprintf(arg + pos,
 273                           "unacknowledged keepalives: %ld", sc->seqRetries);
 274                         resp->header.arglen = pos + 1;
 275                         break;
 276                     }
 277                 default:
 278                         error = EINVAL;
 279                         break;
 280                 }
 281                 break;
 282         case NGM_CISCO_COOKIE:
 283                 switch (msg->header.cmd) {
 284                 case NGM_CISCO_GET_IPADDR:      /* could be a late reply! */
 285                         if ((msg->header.flags & NGF_RESP) == 0) {
 286                                 struct in_addr *ips;
 287
 288                                 NG_MKRESPONSE(resp, msg,
 289                                     2 * sizeof(*ips), M_NOWAIT);
 290                                 if (!resp) {
 291                                         error = ENOMEM;
 292                                         break;
 293                                 }
 294                                 ips = (struct in_addr *) resp->data;
 295                                 ips[0] = sc->localip;
 296                                 ips[1] = sc->localmask;
 297                                 break;
 298                         }
 299                         /* FALLTHROUGH */       /* ...if it's a reply */
 300                 case NGM_CISCO_SET_IPADDR:
 301                     {
 302                         struct in_addr *const ips = (struct in_addr *)msg->data;
 303
 304                         if (msg->header.arglen < 2 * sizeof(*ips)) {
 305                                 error = EINVAL;
 306                                 break;
 307                         }
 308                         sc->localip = ips[0];
 309                         sc->localmask = ips[1];
 310                         break;
 311                     }
 312                 case NGM_CISCO_GET_STATUS:
 313                     {
 314                         struct ng_cisco_stats *stat;
 315
 316                         NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
 317                         if (!resp) {
 318                                 error = ENOMEM;
 319                                 break;
 320                         }
 321                         stat = (struct ng_cisco_stats *)resp->data;
 322                         stat->seqRetries = sc->seqRetries;
 323                         stat->keepAlivePeriod = KEEPALIVE_SECS;
 324                         break;
 325                     }
 326                 default:
 327                         error = EINVAL;
 328                         break;
 329                 }
 330                 break;
 331         default:
 332                 error = EINVAL;
 333                 break;
 334         }
 335         if (rptr)
 336                 *rptr = resp;
 337         else if (resp)
 338                 kfree(resp, M_NETGRAPH);
 339         kfree(msg, M_NETGRAPH);
 340         return (error);
 341 }
 342
 343 /*
 344  * Receive data
 345  */
 346 static int
 347 cisco_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
 348 {
 349         const sc_p sc = hook->node->private;
 350         struct protoent *pep;
 351         struct cisco_header *h;
 352         int error = 0;
 353
 354         if ((pep = hook->private) == NULL)
 355                 goto out;
 356
 357         /* If it came from our downlink, deal with it separately */
 358         if (pep->af == 0xffff)
 359                 return (cisco_input(sc, m, meta));
 360
 361         /* OK so it came from a protocol, heading out. Prepend general data
 362            packet header. For now, IP,IPX only  */
 363         M_PREPEND(m, CISCO_HEADER_LEN, M_NOWAIT);
 364         if (!m) {
 365                 error = ENOBUFS;
 366                 goto out;
 367         }
 368         h = mtod(m, struct cisco_header *);
 369         h->address = CISCO_UNICAST;
 370         h->control = 0;
 371
 372         switch (pep->af) {
 373         case AF_INET:           /* Internet Protocol */
 374                 h->protocol = htons(ETHERTYPE_IP);
 375                 break;
 376         case AF_INET6:
 377                 h->protocol = htons(ETHERTYPE_IPV6);
 378                 break;
 379         case AF_IPX:            /* Novell IPX Protocol */
 380                 h->protocol = htons(ETHERTYPE_IPX);
 381                 break;
 382         default:
 383                 error = EAFNOSUPPORT;
 384                 goto out;
 385         }
 386
 387         /* Send it */
 388         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 389         return (error);
 390
 391 out:
 392         NG_FREE_DATA(m, meta);
 393         return (error);
 394 }
 395
 396 /*
 397  * Shutdown node
 398  */
 399 static int
 400 cisco_rmnode(node_p node)
 401 {
 402         const sc_p sc = node->private;
 403
 404         node->flags |= NG_INVALID;
 405         ng_cutlinks(node);
 406         ng_unname(node);
 407         node->private = NULL;
 408         ng_unref(sc->node);
 409         kfree(sc, M_NETGRAPH);
 410         return (0);
 411 }
 412
 413 /*
 414  * Disconnection of a hook
 415  *
 416  * For this type, removal of the last link destroys the node
 417  */
 418 static int
 419 cisco_disconnect(hook_p hook)
 420 {
 421         const sc_p sc = hook->node->private;
 422         struct protoent *pep;
 423
 424         /* Check it's not the debug hook */
 425         if ((pep = hook->private)) {
 426                 pep->hook = NULL;
 427                 if (pep->af == 0xffff) {
 428                         /* If it is the downstream hook, stop the timers */
 429                         callout_stop(&sc->timeout);
 430                 }
 431         }
 432
 433         /* If no more hooks, remove the node */
 434         if (hook->node->numhooks == 0)
 435                 ng_rmnode(hook->node);
 436         return (0);
 437 }
 438
 439 /*
 440  * Receive data
 441  */
 442 static int
 443 cisco_input(sc_p sc, struct mbuf *m, meta_p meta)
 444 {
 445         const struct cisco_header *h;
 446         struct cisco_header hdrbuf;
 447         struct protoent *pep;
 448         int error = 0;
 449
 450         /* Sanity check header length */
 451         if (m->m_pkthdr.len < sizeof(*h)) {
 452                 error = EINVAL;
 453                 goto drop;
 454         }
 455
 456         /* Get cisco header */
 457         if (m->m_len >= sizeof(*h))                     /* the common case */
 458                 h = mtod(m, const struct cisco_header *);
 459         else {
 460                 m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
 461                 h = &hdrbuf;
 462         }
 463         m_adj(m, sizeof(*h));
 464
 465         /* Check header address */
 466         switch (h->address) {
 467         default:                /* Invalid Cisco packet. */
 468                 goto drop;
 469         case CISCO_UNICAST:
 470         case CISCO_MULTICAST:
 471                 /* Don't check the control field here (RFC 1547). */
 472                 switch (ntohs(h->protocol)) {
 473                 default:
 474                         goto drop;
 475                 case CISCO_KEEPALIVE:
 476                     {
 477                         const struct cisco_packet *p;
 478                         struct cisco_packet pktbuf;
 479
 480                         /* Sanity check packet length */
 481                         if (m->m_pkthdr.len < sizeof(*p)) {
 482                                 error = EINVAL;
 483                                 goto drop;
 484                         }
 485
 486                         /* Get cisco packet */
 487                         if (m->m_len >= sizeof(*p))     /* the common case */
 488                                 p = mtod(m, const struct cisco_packet *);
 489                         else {
 490                                 m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
 491                                 p = &pktbuf;
 492                         }
 493
 494                         /* Check packet type */
 495                         switch (ntohl(p->type)) {
 496                         default:
 497                                 log(LOG_WARNING,
 498                                     "cisco: unknown cisco packet type: 0x%"PRIx32"\n",
 499                                        ntohl(p->type));
 500                                 break;
 501                         case CISCO_ADDR_REPLY:
 502                                 /* Reply on address request, ignore */
 503                                 break;
 504                         case CISCO_KEEPALIVE_REQ:
 505                                 sc->remote_seq = ntohl(p->par1);
 506                                 if (sc->local_seq == ntohl(p->par2)) {
 507                                         sc->local_seq++;
 508                                         sc->seqRetries = 0;
 509                                 }
 510                                 break;
 511                         case CISCO_ADDR_REQ:
 512                             {
 513                                 struct ng_mesg *msg, *resp;
 514
 515                                 /* Ask inet peer for IP address information */
 516                                 if (sc->inet.hook == NULL)
 517                                         goto nomsg;
 518                                 NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
 519                                     NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
 520                                 if (msg == NULL)
 521                                         goto nomsg;
 522                                 ng_send_msg(sc->node, msg,
 523                                     NG_CISCO_HOOK_INET, &resp);
 524                                 if (resp != NULL)
 525                                         cisco_rcvmsg(sc->node, resp, ".", NULL);
 526
 527                 nomsg:
 528                                 /* Send reply to peer device */
 529                                 error = cisco_send(sc, CISCO_ADDR_REPLY,
 530                                             ntohl(sc->localip.s_addr),
 531                                             ntohl(sc->localmask.s_addr));
 532                                 break;
 533                             }
 534                         }
 535                         goto drop;
 536                     }
 537                 case ETHERTYPE_IP:
 538                         pep = &sc->inet;
 539                         break;
 540                 case ETHERTYPE_IPV6:
 541                         pep = &sc->inet6;
 542                         break;
 543                 case ETHERTYPE_IPX:
 544                         pep = &sc->ipx;
 545                         break;
 546                 }
 547                 break;
 548         }
 549
 550         /* Drop if payload is empty */
 551         if (m->m_pkthdr.len == 0) {
 552                 error = EINVAL;
 553                 goto drop;
 554         }
 555
 556         /* Send it on */
 557         if (pep->hook == NULL)
 558                 goto drop;
 559         NG_SEND_DATA(error, pep->hook, m, meta);
 560         return (error);
 561
 562 drop:
 563         NG_FREE_DATA(m, meta);
 564         return (error);
 565 }
 566
 567
 568 /*
 569  * Send keepalive packets, every 10 seconds.
 570  */
 571 static void
 572 cisco_keepalive(void *arg)
 573 {
 574         const sc_p sc = arg;
 575
 576         crit_enter();
 577         cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
 578         sc->seqRetries++;
 579         crit_exit();
 580         callout_reset(&sc->timeout, hz * KEEPALIVE_SECS,
 581                         cisco_keepalive, sc);
 582 }
 583
 584 /*
 585  * Send Cisco keepalive packet.
 586  */
 587 static int
 588 cisco_send(sc_p sc, int type, long par1, long par2)
 589 {
 590         struct cisco_header *h;
 591         struct cisco_packet *ch;
 592         struct mbuf *m;
 593         u_long  t;
 594         int     error = 0;
 595         meta_p  meta = NULL;
 596         struct timeval time;
 597
 598         getmicrotime(&time);
 599
 600         MGETHDR(m, M_NOWAIT, MT_DATA);
 601         if (!m)
 602                 return (ENOBUFS);
 603
 604         t = (time.tv_sec - boottime.tv_sec) * 1000;
 605         m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
 606         m->m_pkthdr.rcvif = 0;
 607
 608         h = mtod(m, struct cisco_header *);
 609         h->address = CISCO_MULTICAST;
 610         h->control = 0;
 611         h->protocol = htons(CISCO_KEEPALIVE);
 612
 613         ch = (struct cisco_packet *) (h + 1);
 614         ch->type = htonl(type);
 615         ch->par1 = htonl(par1);
 616         ch->par2 = htonl(par2);
 617         ch->rel = -1;
 618         ch->time0 = htons((u_short) (t >> 16));
 619         ch->time1 = htons((u_short) t);
 620
 621         NG_SEND_DATA(error, sc->downstream.hook, m, meta);
 622         return (error);
 623 }